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Sample records for multi-generation tracheobronchial conducting

  1. Computer simulation of airflow through a multi-generation tracheobronchial conducting airway

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    Fan, B.; Cheng, Yung-Sung; Yeh, Hsu-Chi

    1995-12-01

    Knowledge of airflow patterns in the human lung is important for an analysis of lung diseases and drug delivery of aerosolized medicine for medical treatment. However, very little systematic information is available on the pattern of airflow in the lung and on how this pattern affects the deposition of toxicants in the lung, and the efficacy of aerosol drug therapy. Most previous studies have only considered the airflow through a single bifurcating airway. However, the flow in a network of more than one bifurcation is more complicated due to the effect of interrelated lung generations. Because of the variation of airway geometry and flow condition from generation to generation, a single bifurcating airway cannot be taken as a representative for the others in different generations. The flow in the network varies significantly with airway generations because of a redistribution of axial momentum by the secondary flow motions. The influence of the redistribution of flow is expected in every generation. Therefore, a systematic information of the airflow through a multi-generation tracheobronchial conducting airway is needed, and it becomes the purpose of this study. This study has provided information on airflow in a lung model which is necessary to the study of the deposition of toxicants and therapeutic aerosols.

  2. Computer simulation of airflow through a multi-generation tracheobronchial conducting airway

    International Nuclear Information System (INIS)

    Fan, B.; Cheng, Yung-Sung; Yeh, Hsu-Chi.

    1995-01-01

    Knowledge of airflow patterns in the human lung is important for an analysis of lung diseases and drug delivery of aerosolized medicine for medical treatment. However, very little systematic information is available on the pattern of airflow in the lung and on how this pattern affects the deposition of toxicants in the lung, and the efficacy of aerosol drug therapy. Most previous studies have only considered the airflow through a single bifurcating airway. However, the flow in a network of more than one bifurcation is more complicated due to the effect of interrelated lung generations. Because of the variation of airway geometry and flow condition from generation to generation, a single bifurcating airway cannot be taken as a representative for the others in different generations. The flow in the network varies significantly with airway generations because of a redistribution of axial momentum by the secondary flow motions. The influence of the redistribution of flow is expected in every generation. Therefore, a systematic information of the airflow through a multi-generation tracheobronchial conducting airway is needed, and it becomes the purpose of this study. This study has provided information on airflow in a lung model which is necessary to the study of the deposition of toxicants and therapeutic aerosols

  3. Transport and Deposition of Micro-and Nano-Particles in Human Tracheobronchial Tree by an Asymmetric Multi-Level Bifurcation Model

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    Lin Tian

    2012-06-01

    Full Text Available Transport and deposition of particles in the upper tracheobronchial tree were analyzed using a multi-level asymmetric lung bifurcation model. The first three generations of tracheobronchial tree were included in the study. The laryngeal jet at the trachea entrance was modeled as an effective turbulence disturbance, and the study was focused on how to accurately simulate the airflow and predict the motion of the inhaled particles. Downstream in the lower level of the bronchial region, a laminar flow model was used, as smoother flow condition was expected. Transport and deposition of nano- and micro-scale spherical particles in the range of 0.01 μm to 30 μm were evaluated. The particle local deposition pattern and deposition rate in the lung bifurcation was discussed. The proposed multi-level asymmetric lung bifurcation model was found to be flexible, easy to use and computationally highly efficient. It was also shown that the selection of the anisotropic Reynolds stress transport turbulence model (RSTM was appropriate, and the use of the enhanced two-layer model boundary treatment was needed for accurate simulation of the turbulent airflow conditions in the upper airways.

  4. Management of Tracheobronchial Strictures

    International Nuclear Information System (INIS)

    Shin, Ji Hoon; Song, Ho-Young; Shim, Tae Sun

    2004-01-01

    Recently, the use of tracheobronchial stents has increased greatly sue to the advantages of easy placement and prompt airway relief. in addition, trachebronchial stents provide an alternative to open surgical procedures in select patients with benign tracheobronchial stenosis or obstruction, in particular those with tracheobronchial tuberculosis. This paper review the indications for tracheobronchial stent placement, appropriate stent selection, pre-procedure evaluation, and the results of stent placement for benign and malignant tracheobronchial strictures

  5. Tracheobronchial Branching Anomalies

    International Nuclear Information System (INIS)

    Hong, Min Ji; Kim, Young Tong; Jou, Sung Shick; Park, A Young

    2010-01-01

    There are various congenital anomalies with respect to the number, length, diameter, and location of tracheobronchial branching patterns. The tracheobronchial anomalies are classified into two groups. The first one, anomalies of division, includes tracheal bronchus, cardiac bronchus, tracheal diverticulum, pulmonary isomerism, and minor variations. The second one, dysmorphic lung, includes lung agenesis-hypoplasia complex and lobar agenesis-aplasia complex

  6. Tracheobronchial Branching Anomalies

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    Hong, Min Ji; Kim, Young Tong; Jou, Sung Shick [Soonchunhyang University, Cheonan Hospital, Cheonan (Korea, Republic of); Park, A Young [Soonchunhyang University College of Medicine, Asan (Korea, Republic of)

    2010-04-15

    There are various congenital anomalies with respect to the number, length, diameter, and location of tracheobronchial branching patterns. The tracheobronchial anomalies are classified into two groups. The first one, anomalies of division, includes tracheal bronchus, cardiac bronchus, tracheal diverticulum, pulmonary isomerism, and minor variations. The second one, dysmorphic lung, includes lung agenesis-hypoplasia complex and lobar agenesis-aplasia complex

  7. Outcomes of Temporary Partially Covered Stent Placement for Benign Tracheobronchial Stenosis

    International Nuclear Information System (INIS)

    Ma, Ji; Han, Xinwei; Wu, Gang; Jiao, Dechao; Ren, Kewei; Bi, Yonghua

    2016-01-01

    PurposeTo evaluate the intermediate outcomes of temporary partially covered tracheobronchial stenting in patients with benign tracheobronchial stenosis.Materials and MethodsWe conducted a retrospective study of patients with benign tracheobronchial stenosis who underwent stent placement. All stents were removed approximately 3 months after placement. Respiratory function was assessed using the visual analogue scale (VAS) and Karnofsky performance status scale (KPS) before and after stent placement. The lumen diameters of the stenotic lesions were measured using chest computed tomography (CT) and compared between before stent placement and after stent removal.ResultsA total of 51 stents were successfully placed in consecutive 51 patients with benign tracheobronchial stenosis. No serious complications occurred. The mean VAS and KPS scores significantly improved after stent removal (6.291 ± 0.495 and 25.352 ± 10.533, respectively) compared with those before stent placement (1.493 ± 0.504 and 60.140 ± 16.344, respectively; P   0.05).ConclusionTemporary partially covered stenting may be a safe and effective treatment for benign tracheobronchial stenosis.

  8. Outcomes of Temporary Partially Covered Stent Placement for Benign Tracheobronchial Stenosis.

    Science.gov (United States)

    Ma, Ji; Han, Xinwei; Wu, Gang; Jiao, Dechao; Ren, Kewei; Bi, Yonghua

    2016-08-01

    To evaluate the intermediate outcomes of temporary partially covered tracheobronchial stenting in patients with benign tracheobronchial stenosis. We conducted a retrospective study of patients with benign tracheobronchial stenosis who underwent stent placement. All stents were removed approximately 3 months after placement. Respiratory function was assessed using the visual analogue scale (VAS) and Karnofsky performance status scale (KPS) before and after stent placement. The lumen diameters of the stenotic lesions were measured using chest computed tomography (CT) and compared between before stent placement and after stent removal. A total of 51 stents were successfully placed in consecutive 51 patients with benign tracheobronchial stenosis. No serious complications occurred. The mean VAS and KPS scores significantly improved after stent removal (6.291 ± 0.495 and 25.352 ± 10.533, respectively) compared with those before stent placement (1.493 ± 0.504 and 60.140 ± 16.344, respectively; P  0.05). Temporary partially covered stenting may be a safe and effective treatment for benign tracheobronchial stenosis.

  9. 3-D printouts of the tracheobronchial tree generated from CT images as an aid to management in a case of tracheobronchial chondromalacia caused by relapsing polychondritis.

    Science.gov (United States)

    Tam, Matthew David; Laycock, Stephen David; Jayne, David; Babar, Judith; Noble, Brendon

    2013-08-01

    This report concerns a 67 year old male patient with known advanced relapsing polychondritis complicated by tracheobronchial chondromalacia who is increasingly symptomatic and therapeutic options such as tracheostomy and stenting procedures are being considered. The DICOM files from the patient's dynamic chest CT in its inspiratory and expiratory phases were used to generate stereolithography (STL) files and hence print out 3-D models of the patient's trachea and central airways. The 4 full-sized models allowed better understanding of the extent and location of any stenosis or malacic change and should aid any planned future stenting procedures. The future possibility of using the models as scaffolding to generate a new cartilaginous upper airway using regenerative medical techniques is also discussed.

  10. Multi-slice spiral CT in the diagnosis of congenital heart diseases associated with tracheobronchial stenosis in children

    International Nuclear Information System (INIS)

    Wang Rongpin; Liang Changhong; Huang Meiping; Liu Hui; Cui Yanhai; Liu Qishun

    2010-01-01

    Objective: To explore the diagnostic value of post processing techniques of MSCT for diagnosing congenital heart disease associated with tracheobronchial stenosis in children. Methods: Thirty four patients with congenital heart disease complicated by tracheobronchial stenosis were evaluated with MSCT. MPR, CPR, MinIP and VR were performed to show the tracheobronchial morphology. Findings in 43 segments of 32 cases were compared with the findings of surgical operation. Mann-Whitney test was employed to assess the significance of measurement between the post processing techniques and the operation. Results: The length of stenotic segments were variable seen at operation, with values between 4- 39 mm in trachea, 4-33 mm in main bronchi and 3-12 mm in lobe bronchi, respectively. The biggest difference between the measurement of operation and MSCT was 4 mm (3 segments). Other differences of stenotic segments were within 3 mm. Six segments exhibited mild, 16 moderate and 21 severe stenosis at surgery. By contrast, five segments exhibited mild, 17 moderate and 21 severe stenosis by MPR or CPR, 2 mild, 9 moderate and 32 severe stenosis by MinIP and 4 mild, 11 moderate and 28 sever stenosis by VR, respectively. There was no significant difference in measuring the degree of tracheobronchial stenosis between MPR or CPR, VR and the surgery (Z=-0.105, -1.479; P>0.05), while MinIP frequently overrated the degree of stenosis compared with the measurement at surgery (Z=-2.484, P=0.013). Conclusion: The integrated three dimensional reformations of MSCT scan can accurately evaluate the degree and extent of congenital heart disease associated with tracheobronchial stenosis in children and provide valuable information for clinical management. (authors)

  11. Outcomes of Temporary Partially Covered Stent Placement for Benign Tracheobronchial Stenosis

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    Ma, Ji; Han, Xinwei, E-mail: hanxinwei2006@163.com; Wu, Gang; Jiao, Dechao; Ren, Kewei; Bi, Yonghua [The First Affiliated Hospital of Zhengzhou University, Department of Interventional Radiology (China)

    2016-08-15

    PurposeTo evaluate the intermediate outcomes of temporary partially covered tracheobronchial stenting in patients with benign tracheobronchial stenosis.Materials and MethodsWe conducted a retrospective study of patients with benign tracheobronchial stenosis who underwent stent placement. All stents were removed approximately 3 months after placement. Respiratory function was assessed using the visual analogue scale (VAS) and Karnofsky performance status scale (KPS) before and after stent placement. The lumen diameters of the stenotic lesions were measured using chest computed tomography (CT) and compared between before stent placement and after stent removal.ResultsA total of 51 stents were successfully placed in consecutive 51 patients with benign tracheobronchial stenosis. No serious complications occurred. The mean VAS and KPS scores significantly improved after stent removal (6.291 ± 0.495 and 25.352 ± 10.533, respectively) compared with those before stent placement (1.493 ± 0.504 and 60.140 ± 16.344, respectively; P < 0.05). The mean lumen transverse diameters of the stenotic site in trachea and main bronchus after stent removal (17.235 ± 3.457 and 8.993 ± 0.961 mm; 1 month post-removal; 16.353 ± 4.132 and 8.357 ± 1.082 mm; 6 months post-removal) were significantly larger than those before stent placement (7.876 ± 2.351 and 2.143 ± 0.770 mm, respectively; P < 0.05). However, the mean lumen diameters between 1 and 6 months after stent removal had no significant difference (P > 0.05).ConclusionTemporary partially covered stenting may be a safe and effective treatment for benign tracheobronchial stenosis.

  12. CT assessment of tracheobronchial anomaly in left pulmonary artery sling

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    Zhong, Yu-Min M.; Zhu, Ming; Sun, Ai-Min M.; Wang, Qian [Shanghai Jiao Tong University School of Medicine, Department of Radiology, Shanghai Children' s Medical Center, Shanghai (China); Jaffe, Richard B. [Primary Children' s Medical Center, Department of Medical Imaging, Salt Lake City, UT (United States); Gao, Wei [Shanghai Jiao Tong University School of Medicine, Department of Cardiology, Shanghai Children' s Medical Center, Shanghai (China)

    2010-11-15

    The left pulmonary artery sling (LPAS) is a rare vascular anomaly where the left pulmonary artery arises from the right pulmonary artery, passes over the right bronchus, and goes posteriorly between the trachea and esophagus. The LPAS is frequently associated with cardiac and non-cardiac defects including tracheobronchial abnormalities. To evaluate the utility of multislice CT (MSCT) and helical CT (HCT) in diagnosing and defining the tracheobronchial anomaly and anatomic relationships between the trachea and aberrant left pulmonary artery. MSCT or HCT was performed in 27 children to determine the tracheobronchial anatomy and identify tracheobronchial stenosis. Eighteen children underwent surgery. According to the Wells [6] classification of LPAS, which includes two main types and two subtypes, there were eight cases of type 1A, five cases of type 1B, six cases of type 2A and eight cases of type 2B in this group. Twenty-four of the 27 children had substantial tracheobronchial stenosis. Four died before surgery; the 18 had reanastomosis of the left pulmonary artery. Five children also had tracheoplasty; three died after surgery. CT, especially MSCT, is an ideal modality for simultaneously identifying aberrant left pulmonary artery and any associated tracheobronchial anomaly. The Wells classification is useful for operative planning. (orig.)

  13. An ovine in vivo framework for tracheobronchial stent analysis.

    Science.gov (United States)

    McGrath, Donnacha J; Thiebes, Anja Lena; Cornelissen, Christian G; O'Shea, Mary B; O'Brien, Barry; Jockenhoevel, Stefan; Bruzzi, Mark; McHugh, Peter E

    2017-10-01

    Tracheobronchial stents are most commonly used to restore patency to airways stenosed by tumour growth. Currently all tracheobronchial stents are associated with complications such as stent migration, granulation tissue formation, mucous plugging and stent strut fracture. The present work develops a computational framework to evaluate tracheobronchial stent designs in vivo. Pressurised computed tomography is used to create a biomechanical lung model which takes into account the in vivo stress state, global lung deformation and local loading from pressure variation. Stent interaction with the airway is then evaluated for a number of loading conditions including normal breathing, coughing and ventilation. Results of the analysis indicate that three of the major complications associated with tracheobronchial stents can potentially be analysed with this framework, which can be readily applied to the human case. Airway deformation caused by lung motion is shown to have a significant effect on stent mechanical performance, including implications for stent migration, granulation formation and stent fracture.

  14. Treatment of malignant or benign tracheobronchial stenosis by home made Nitrol stents

    International Nuclear Information System (INIS)

    Zhang Fanchang; Luo Zhehuang; Hu Xunying; Liu Jiubao; Jin Aifang

    2002-01-01

    Objective: To evaluate the therapeutic effects of home made Nitrol stents in the treatment of malignant or benign tracheobronchial stenosis. Methods: Thirteen patients with malignant or benign tracheobronchial stenosis were treated by Nitrol stents. The stenosed sites located in trachea in 5, tracheo-bronchi in 6, main bronchus in 2. All cases were malignant except one was benign. Results: 15 stents were successfully placed the expected position with dyspnea rapidly improved. The average survival time was 11.4 months. Conclusions: It is an effective way to place Nitrol stent in treatment of tracheobronchial stenosis under x-ray guidance with fiber tracheo-bronchoscopy

  15. Usefulness of a functional tracheobronchial phantom for interventional procedure

    International Nuclear Information System (INIS)

    Kim, Tae Hyung; Lim, Cheong Hwan; Kim, Jeong Koo

    2003-01-01

    To evaluate usefulness of a functional tracheobronchial phantom for interventional procedure. The functional phantom was made as a actual size with human normal anatomy used silicone and a paper clay mold. A tracheobronchial-shape clay mold was placed inside a square box and liquid silicone was poured. After the silicone was formed, the clay was removed. We measured film density and tracheobronchial angle at the human, animal and phantom respectively. The film density of trachea part were 0.76 (± 0.011) in human, 0.97 (± 0.015) in animal, 0.45 (± 0.016) in phantom. The tracheobronchial bifurcation part measured 0.51 (± 0.006) in human, 0.65 (± 0.005) in animal, 0.65 (± 0.008) in phantom. The right bronchus part measured 0.14 (± 0.008) in human, 0.59 (± 0.014) in animal and 0.04 (± 0.007) in phantom. The left bronchus were 0.54 (± 0.004) in human, 0.54 (± 0.008) in animal and 0.08 (± 0.008) in phantom. At the stent part were 0.54 (± 0.004) in human, 0.59 (± 0.011) in animal and 0.04 (± 0.007) in phantom, respectively. The tracheobronchial angle of the left bronchus site were 42.6 (± 2.07).deg. in human, 43.4 (± 2.40).deg. in animal and 35 (± 2.00).deg. in phantom, respectively. The right bronchus site were 32.8 (± 2.77).deg. in human, 34.6 (± 1.94).deg. in animal and 50.2 (± 1.30).deg. in phantom, respectively. The phantom was useful for in-vitro testing of tracheobronchial interventional procedure, since it was easy to reproduce

  16. Interdisciplinary interventional therapy for tracheobronchial stenosis with modern metal net stents

    International Nuclear Information System (INIS)

    Rieger, J.; Linsenmaier, U.; Fedorowski, A.; Pfeifer, K.J.; Hautmann, H.; Huber, R.M.

    2002-01-01

    Study objectives: Assessment of the therapeutic potential of tracheobronchial stenting for obstructive tracheobronchial disease, in-vivo comparison of different stent types and development of helpful criteria for choosing the suitable stent type. Material and Methods: Prospective case analysis. Between 1993 and 1999 53 stents were implanted into the tracheobronchial system of 39 consecutive patients with benign or malignant airway obstruction. Every single stent (26 Strecker Stents, 18 Wallstents, 6 Accuflex Nitinolstents, 1 Dumon-, 1 Ruesch- and 1 Palmazstent) was recorded in an unified database. Analysis comprised clinical effectiveness, lung function if possible, relevant complications and radiologic follow-up parameters. The probability of their remaining within the tracheobronchial system, of their remaining undislocated and uncompressed was calculated using Kaplan-Meier analysis for three stent types. Results: Stent placement proved itself to be an effective treatment in 86% of the patients. Resistance could be normalized in 9/9 patients. Kaplan-Meier analysis clearly revealed a higher probability for the Wall- and Nitinolstent to remain within the tracheobronchial system and to remain uncompressed. Dislocation also occurred more rarely. Explanation of the Wallstent, however, if desired, was much more difficult compared to the Strecker stent. The Wallstent also occasionally led to the formation of granulation tissue especially at the proximal stent end and, as such, required reintervention. (orig.) [de

  17. Factors leading to tracheobronchial self-expandable metallic stent fracture.

    Science.gov (United States)

    Chung, Fu-Tsai; Lin, Shu-Min; Chen, Hao-Cheng; Chou, Chun-Liang; Yu, Chih-Teng; Liu, Chien-Ying; Wang, Chun-Hua; Lin, Horng-Chyuan; Huang, Chien-Da; Kuo, Han-Pin

    2008-11-01

    This retrospective study was to determine factors that contribute to self-expandable metallic stent fracture in patients with tracheobronchial disease. From 2001 to 2006, 139 patients (age, 62.1 +/- 15.4 years; range, 23-87 years) with benign (n = 62) and malignant (n = 77) tracheobronchial disease received 192 Ultraflex (Boston Scientific, Natick, Mass) self-expandable metallic stents (98 in patients with benign disease and 94 in patients with malignant disease). Seventeen fractured self-expandable metallic stents were found; the incidence was 12.2% (17/139 patients) among patients with tracheobronchial disease. Tortuous airway (odds ratio, 4.06; 95% confidence interval, 1.04-18.34; P = .04) independently predicted self-expandable metallic stent fracture. Most self-expandable metallic stent fractures (64.7%, 11/17) were detected 500 to 1000 days after self-expandable metallic stent implantation. Clinical presentations for patients with fractured self-expandable metallic stents included dyspnea exacerbation (70.6%, 12/17) and cough (23.5%, 4/17). Self-expandable metallic stent fracture is not uncommon in patients with tracheobronchial disease. Tortuous airway is an independent predictor for it. Although management of the fractured self-expandable metallic stent in our study was feasible and safe, self-expandable metallic stents should be restricted to a more select population.

  18. Tracheobronchial Cast Production and Use in an Undergraduate Human Anatomy Course

    Science.gov (United States)

    Cope, Lee Anne

    2008-01-01

    Silastic E RTV silicone was used to produce tracheobronchial cast for use in an undergraduate human anatomy course. Following air-drying, the trachea and lungs were injected with E RTV silicone and allowed to cure for 24 hr. The parenchyma was then removed from the tracheobronchial cast by maceration and boiling and then whitened in a 10% solution…

  19. Multi-slice computed tomography assessment of bronchial compression with absent pulmonary valve

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    Zhong, Yu-Min; Sun, Ai-Min; Wang, Qian; Zhu, Ming; Qiu, Hai-Sheng [Shanghai Children' s Medical Center and Shanghai Jiao Tong University Medical School, Department of Radiology, Shanghai (China); Jaffe, Richard B. [Primary Children' s Medical Center, Department of Medical Imaging, Salt Lake City, UT (United States); Liu, Jin-Fen [Shanghai Children' s Medical Center, Department of Cardiothoracic Surgery, Shanghai (China); Gao, Wei [Shanghai Children' s Medical Center and Shanghai Jiao Tong University Medical School, Department of Cardiology, Shanghai (China); Berdon, Walter E. [Children' s Hospital of New York, Department of Radiology, New York, NY (United States)

    2014-07-15

    Absent pulmonary valve is a rare cardiovascular anomaly that can result in profound tracheobronchial compression. To demonstrate the advantage of multi-slice CT in diagnosing tracheobronchial compression, its severity as related to the adjacent dilated pulmonary arteries, and associated lung and cardiac lesions. We included children with absent pulmonary valve who were reviewed by multi-slice CT during a 17-year period. The number and locations of stenoses and lung lesions were noted and the severity of stenosis was categorized. The diameter of the pulmonary artery was measured and associated cardiac defects were demonstrated. Thirty-one children (14 girls and 17 boys) were included. Of these, 29 had ventricular septal defect and 2 had an intact ventricular septum. Twenty-nine children (94%) had tracheobronchial compression, judged to be mild in nine children (31%), moderate in 10 (34%) and severe in 10 (34%). The different locations of the stenosis (carina, main bronchi, lobar and segmental bronchi) were observed. And the number and location of lung lesions demonstrated that the right middle and left upper and lower lobes were often affected. The diameter of the pulmonary artery in these children was well above normal published values, and Spearman rank correlation analysis showed a correlation between the size of the pulmonary artery and the severity of the tracheobronchial stenosis. Nineteen children (61%) underwent surgery and 4 of these children had a multi-slice CT post-operative follow-up study. Absent pulmonary valve can cause significant morbidity and mortality in children. Multi-slice CT can accurately depict areas of tracheobronchial compression, associated lung lesions and cardiac defects, helping to direct the surgeon. (orig.)

  20. [Eight Cases of Esophagus and Tracheobronchial Stenting for Advanced Esophageal Cancer].

    Science.gov (United States)

    Nakahara, Yujiro; Takachi, Ko; Tsujimura, Naoto; Wakasugi, Masaki; Hirota, Masaki; Matsumoto, Takashi; Takemoto, Hiroyoshi; Nishioka, Kiyonori; Oshima, Satoshi

    2017-11-01

    Malignant stricture and fistula of the esophagus and tracheobronchus adversely affect the quality of life(QOL)in patients with advanced esophageal cancer. Stenting is one ofthe therapies available for these patients. We investigated the outcomes ofesophagus and tracheobronchial stenting in our institution. Eight patients with advanced esophageal cancer underwent double stenting from 2010 to 2016. Among them, 4 patients underwent double stenting as planned. One patient underwent an emergency tracheal stenting because ofstenosis ofthe trachea caused by esophageal stenting. Three patients underwent tracheobronchial stenting later on because ofan increase in the tumor size after esophageal stenting. Dysphagia score was improved in 5(67.5%)out ofthe 8 patients. Respiratory symptoms were improved in all patients, and 4 patients(50.0%) were discharged. The median survival time after esophageal stenting was 70.5 days. Esophagus and tracheobronchial stenting for advanced esophageal cancer was useful for the improvement of the QOL.

  1. Tracheobronchial injuries in blunt chest trauma

    Directory of Open Access Journals (Sweden)

    vahid Montazeri

    2004-01-01

    Full Text Available Introduction: Tracheobronchial injuries are uncommon but potentially fatal complication of blunt thoracic trauma harboring a high morbidity and mortality if not diagnosed early . A recent series gleaning cases from four major Trauma Center in Los Angeles nine cases in a seven- year period , but the incidence of these injuries has been increasing recently. This has been attributed to improvement in hospital care and advanced Trauma Centers and earlier diagnosis of such injuries. Disruption of tight main bronchus is more common, such injuries are often associated with rib or clavicular fractures. Findings: Clinical and paraclinical data gathered from records of three patients referred with tracheobronchial injuries during the recent ten years have been reviewed .These include clinical manifestations, diagnostic findings, treatment modality and clinical course. The outcome has been satisfactory in all three patients who have undergone operation 2-5 hours after sustaining the injury. We have not had any mortality. Conclusion: These results are similar to those of other series emphasizing over early diagnosis and treatment of such injuries .

  2. Interventional management of tracheobronchial strictures

    OpenAIRE

    Shin, Ji Hoon

    2010-01-01

    Tracheobronchial balloon dilation and stent placement have been well used in the treatment of patients with benign and/or malignant diseases. Balloon dilation is the first option in the treatment of benign airway stenosis. Although balloon dilation is simple and fast, recurrence rate is high. Stent placement promptly relieves acute airway distress from malignant extraluminal and intraluminal airway obstruction. Temporary stent placement may be an alternative for benign airway strictures refra...

  3. Details of regional particle deposition and airflow structures in a realistic model of human tracheobronchial airways: two-phase flow simulation.

    Science.gov (United States)

    Rahimi-Gorji, Mohammad; Gorji, Tahereh B; Gorji-Bandpy, Mofid

    2016-07-01

    In the present investigation, detailed two-phase flow modeling of airflow, transport and deposition of micro-particles (1-10µm) in a realistic tracheobronchial airway geometry based on CT scan images under various breathing conditions (i.e. 10-60l/min) was considered. Lagrangian particle tracking has been used to investigate the particle deposition patterns in a model comprising mouth up to generation G6 of tracheobronchial airways. The results demonstrated that during all breathing patterns, the maximum velocity change occurred in the narrow throat region (Larynx). Due to implementing a realistic geometry for simulations, many irregularities and bending deflections exist in the airways model. Thereby, at higher inhalation rates, these areas are prone to vortical effects which tend to entrap the inhaled particles. According to the results, deposition fraction has a direct relationship with particle aerodynamic diameter (for dp=1-10µm). Enhancing inhalation flow rate and particle size will largely increase the inertial force and consequently, more particle deposition is evident suggesting that inertial impaction is the dominant deposition mechanism in tracheobronchial airways. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Outcomes after Bronchoscopic Procedures for Primary Tracheobronchial Amyloidosis: Retrospective Study of 6 Cases

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    Ihsan Alloubi

    2012-01-01

    Full Text Available Respiratory amyloidosis is a rare disease which refers to localized aberrant extracellular protein deposits within the airways. Tracheobronchial amyloidosis (TBA refers to the deposition of localized amyloid deposits within the upper airways. Treatments have historically focused on bronchoscopic techniques including debridement, laser ablation, balloon dilation, and stent placement. We present the outcomes after rigid bronchoscopy to remove the amyloid protein causing the airway obstruction in 6 cases of tracheobronchial amyloidosis. This is the first report of primary diffuse tracheobronchial amyloidosis in our department; clinical features, in addition to therapy in the treatment of TBA, are reviewed. This paper shows that, in patients with TBA causing airway obstruction, excellent results can be obtained with rigid bronchoscopy and stenting of the obstructing lesion.

  5. Outcomes after bronchoscopic procedures for primary tracheobronchial amyloidosis: retrospective study of 6 cases.

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    Alloubi, Ihsan; Thumerel, Matthieu; Bégueret, Hugues; Baste, Jean-Marc; Velly, Jean-François; Jougon, Jacques

    2012-01-01

    Respiratory amyloidosis is a rare disease which refers to localized aberrant extracellular protein deposits within the airways. Tracheobronchial amyloidosis (TBA) refers to the deposition of localized amyloid deposits within the upper airways. Treatments have historically focused on bronchoscopic techniques including debridement, laser ablation, balloon dilation, and stent placement. We present the outcomes after rigid bronchoscopy to remove the amyloid protein causing the airway obstruction in 6 cases of tracheobronchial amyloidosis. This is the first report of primary diffuse tracheobronchial amyloidosis in our department; clinical features, in addition to therapy in the treatment of TBA, are reviewed. This paper shows that, in patients with TBA causing airway obstruction, excellent results can be obtained with rigid bronchoscopy and stenting of the obstructing lesion.

  6. Estimation of guinea pig tracheobronchial transport rates using a compartmental model

    International Nuclear Information System (INIS)

    Velasquez, D.J.; Morrow, P.E.

    1984-01-01

    Mucociliary clearance in the tracheobronchial tree of guinea pigs was examined using monodisperse 7.9 μm MMAD polystyrene particles. Animals were exposed for approximately 1 h by inhalation via an intratracheal tube to aerosols tagged with gold-198 and fluorescent dyes. Following exposure, animals were radioactively monitored and sacrificed at predetermined times. The lungs were removed, freeze-dried, sectioned completely, and examined with a fluorescent microscope. Measurements were made of airway diameters where particles were found. An anatomic model for guinea pig lung morphology was used to assign ranges of airway diameters to five zones, which were incorporated into a compartmental model for lung clearance. Kinetic analysis of particle distributions in the zones led to development of first-order equations describing the compartmental clearance. Rate constants obtained from the kinetic analysis were used to estimate mucociliary transport rates in specific bronchial generations, which ranged from approximately 0.001 mm/min in the distal bronchioles to approximately 8 mm/min in the trachea, and resulted in a calculated 24-h clearance time for tracheobronchial clearance in the guinea pig. No evidence for either bronchial penetration by particles or relatively prolonged bronchial retention of particles was found in this study. 22 references, 3 figures, 3 tables

  7. [Tracheobronchial and pulmonary parenchymatous congenital abnormalities requiring surgical treatment in adults].

    Science.gov (United States)

    Mordant, P; De Dominicis, F; Berna, P; Riquet, M

    2012-04-01

    Most tracheobronchial and parenchymatous congenital abnormalities of the respiratory system are diagnosed in early life. However, some lesions may be initially silent and diagnosed only in adulthood. These cases included congenital abnormalies of the tracheobronchial tract (tracheal and/or bronchial stenosis, bronchogenic cysts, bronchial atresia, oesotracheal fistula, oesobronchial fistula, and tracheal diverticulum), and lung parenchyma itself (pulmonary sequestration, congenital cystic adenomatoïd malformation, lobar emphysema, lobar or lung hypoplasia). To avoid dreadful complications, these rare cases deserve surgical management, and must be known by chest physicians and surgeons. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  8. Laser application in tracheobronchial tumors

    Science.gov (United States)

    Rau, B. Krishna; Krishna, Sharon

    2004-09-01

    Ninety three patients with obstructing tracheobronchial tumors were treated with Neodymium: Yttrium - Aluminum - Garnet (Nd:YAG) laser photocoagulation over a period of six years. There were sixty seven Males and 26 Females with a mean age of 44.3 years (range 6- 79 years). 21 benign and 72 malignant lesions were treated with a total 212 sessions of laser photocoagulation (mean 2.4 sessions). The anatomical distribution of lesions were as follows; larynx 9 (three benign and 6 malignant) trachea 39 (27 benign and 12 malignant) left main bronchus 27 (14 malignant) right main bronchus 24 (14 malignant) and vocal cords - 9 (three malignant). There were 21 patients with squamous cell carcinoma, two adenocarcinomas, one adenoid cystic carcinoma, 7 cases of locally infiltrating tumors from thyroid and esophagus, 6 cases of carcinoid tumor and 16 benign lesions. Twenty one patients had a tracheostomy tube in place when treatment was started. Eighteen of the 21 patients with tracheostomy were weaned off the tube in a mean of 5.5 days from the start of treatment. Lumen was restored in 31 (79.4%) patients. In the other eight (20.6%), lumen was achieved, but not sustained. Complications included bleeding in three cases which were managed conservatively, two cases of pneumothorax, and four cases of bronchospasm. There were six deaths during the follow up but none attributable to the procedure. Laser photocoagulation offered effective treatment in the majority of patients with obstructing tracheobronchial tumors, with acceptable morbidity.

  9. Postmortem CT versus forensic autopsy: frequent discrepancies of tracheobronchial content findings.

    Science.gov (United States)

    Zech, Wolf-Dieter; Jackowski, Christian; Schwendener, Nicole; Brencicova, Eva; Schuster, Frederick; Lombardo, Paolo

    2016-01-01

    In their daily forensic casework, the authors experienced discrepancies of tracheobronchial content findings between postmortem computed tomography (PMCT) and autopsy to an extent previously unnoticed in the literature. The goal of this study was to evaluate such discrepancies in routine forensic cases. A total of 327 cases that underwent PMCT prior to routine forensic autopsy were retrospectively evaluated for tracheal and bronchial contents according to PMCT and autopsy findings. Hounsfield unit (HU) values of tracheobronchial contents, causes of death, and presence of pulmonary edema were assessed in mismatching and matching cases. Comparing contents in PMCT and autopsy in each of the separately evaluated compartments of the respiratory tract low positive predictive values were assessed (trachea, 38.2%; main bronchi, 40%; peripheral bronchi, 69.1%) indicating high discrepancy rates. The majority of tracheobronchial contents were viscous stomach contents in matching cases and low radiodensity materials (i.e., HU autopsy occur in a considerable number of cases. Discrepancies may be explained by the runoff of contents via nose and mouth during external examination and the flow back of tracheal and main bronchial contents into the lungs caused by upright movement of the respiratory tract at autopsy.

  10. Effect of 144Ce inhaled in fused-clay particles on the tracheobronchial lymph nodes

    International Nuclear Information System (INIS)

    Hahn, F.F.; Boecker, B.B.; Hobbs, C.H.; Jones, R.K.; Muggenburg, B.A.

    1976-01-01

    Tracheobronchial lymph node changes and lymphopenia are sequelae of inhalation of relatively insoluble radioactive aerosols by beagle dogs. The tracheobronchial lymph nodes from dogs that inhaled 144 Ce in fused-clay particles were examined at intervals from 2 to 730 days after exposure to assess the development of these lesions. Initial lung burdens in the dogs studied ranged from 33 to 63 μCi/kg of body weight. The concentration of radioisotope in the tracheobronchial lymph nodes increased during the first year after exposure and exceeded that in the lung about 100 days after exposure. Autoradiographs of the lymph nodes showed that 144 Ce particles were present in macrophages in the paracortical zone two days after exposure and that concentrations continued to increase in the paracortical zone and medullary cords. Histologic changes in the nodes included atrophy of the germinal centers and lymphocytic follicles, loss of lymphocytes and accumulation of macrophages in the paracortical zone, accumulation of pigment and isotope-laden macrophages in the medullary cords, occasional infiltrates of neutrophils in the medullary cords, and at later time periods focal fibrosis of the medullary cords. Tracheobronchial lymph node weights of the dogs exposed to 144 Ce in fused clay were not decreased until 512 days after exposure. These findings indicate that tracheobronchial lymph nodes accumulate relatively high burdens of 144 Ce after 144 Ce is inhaled in a relatively insoluble form and that the pathologic changes resulting from these burdens are basically atrophy of the nodes. Primary neoplasms in lymph nodes were not observed in dogs with initial lung burdens of 0.0024 to more than 30 μCi/kg of body weight followed for up to 2000 days after exposure. At the higher levels, however, a high incidence of primary pulmonary neoplasia was observed

  11. Gianturco-Rösch Z stents in tracheobronchial stenoses.

    Science.gov (United States)

    Petersen, B D; Uchida, B T; Barton, R E; Keller, F S; Rösch, J

    1995-01-01

    To evaluate expandable metallic Gianturco-Rösch Z (GRZ) stents for treatment of benign and malignant tracheobronchial stenoses. Six patients, ages 45-73 years, were treated for severe dyspnea with placement of GRZ stents. Three patients had benign tracheal lesions (one tracheomalacia, two postoperative) and received uncovered GRZ stents. Three patients had malignant stenoses at the level of the carina; one received an uncovered stent and the other two received silicone-covered GRZ stents. Two patients with benign lesions responded well to stent placement. One was asymptomatic for a year and then was lost to follow-up; the other improved substantially but died of end-stage lung disease 5 months after stent placement. A third patient with a benign high tracheal lesion did poorly; symptoms recurred secondary to inferior migration of a stent, which was removed surgically at 4 months. All patients with malignant lesions improved symptomatically after stent placement and remained without significant dyspnea until death (from 1 to 6 months). Expandable GRZ stents are promising devices for treatment of benign lesions and offer effective palliation of malignant tracheobronchial stenoses.

  12. Experimental models of tracheobronchial stenoses: a useful tool for evaluating airway stents.

    Science.gov (United States)

    Marquette, C H; Mensier, E; Copin, M C; Desmidt, A; Freitag, L; Witt, C; Petyt, L; Ramon, P

    1995-09-01

    Stent implantation is a conservative alternative to open operation for treating benign tracheobronchial strictures. Most of the presently available stents were primarily designed for endovascular use. Their respiratory use entails a risk of iatrogenic complications. From a scientific and from an ethical point of view these risks justify preclinical evaluation of new respiratory stents in experimental models of central airway stenoses. Therefore, an attempt was made to develop such models in piglets and adult minipigs. Tracheal stenoses were obtained by creating first a segmental tracheomalacia through extramucosal resection of cartilaginous arches. The fibrous component of the stenoses was then obtained through bronchoscopic application of a caustic agent causing progressive deep mucosal and submucosal injury. Stenoses of the main bronchi were created by topical application of the caustic agent only. These models demonstrated the typical features of benign fibromalacic tracheobronchial stenoses with constant recurrence after mechanical dilation. Preliminary experiments showed that short-term problems of tolerance of stent prototypes are easily demonstrable in these models. These experimental models, which simulate quite realistically human diseases, offer the opportunity to perfect new tracheobronchial stents specifically designed for respiratory use and to evaluate their long-term tolerance before their use in humans.

  13. Acute tracheobronchial injuries: Impact of imaging on diagnosis and management implications

    International Nuclear Information System (INIS)

    Scaglione, Mariano; Romano, Stefania; Pinto, Antonio; Sparano, Amelia; Scialpi, Michele; Rotondo, Antonio

    2006-01-01

    Purpose: To evaluate the role of chest radiography, single-slice CT and 16-row MDCT in the direct evidence of tracheobronchial injuries. Methods: Patients with acute tracheobronchial injury were identified from the registry of our level 1 trauma center during a 5-year period ending July 2005. Findings at chest radiograph and CT were compared to those shown at bronchoscopy. Results: Eighteen patients with tracheobronchial injury - three patients with cervical trachea injury, eight with thoracic trachea injury and seven with bronchial injury - were identified. Twelve patients had a blunt trauma (67%), six patients had a penetrating (iatrogenic) injury (33%). Chest radiograph directly identified the site of tracheal injury in four cases, showing overdistension of the endotracheal cuff in three cases and displacement of the endotracheal tube in one case. At the level of the bronchi, chest radiograph demonstrated only one injury. CT directly identified the site of tracheal injury in all the cases showing the overdistension of the endotracheal cuff at the level of the thoracic trachea (three cases), posterior herniation of the endotracheal cuff at the thoracic trachea (three cases), lateral endotracheal cuff herniation at the thoracic trachea (one case), tracheal wall discontinuity at the cervical (one case) and at the thoracic trachea (one case) and displacement of endotracheal tube at the cervical trachea (two cases). At the level of the bronchi, CT correctly showed the site of injury in six case including: discontinuity of the left main bronchial wall (two cases), the 'fallen lung' sign (one case), right main bronchial wall enlargement (one case), discontinuity of the right middle bronchial wall (two cases). In one case, CT showed just direct 'air leak' at the level of the carina suggesting main bronchus injury. This finding was confirmed by bronchoscopy. Conclusion: Chest radiograph was helpful for the assessment of iatrogenic tracheal injuries. CT detected the site

  14. Contribution to the study of tracheobronchial and pulmonary deposits in 52 subjects after inhalation of radioactive particles

    International Nuclear Information System (INIS)

    Lange, Pierre.

    1980-03-01

    Particle deposits in the bronchopulmonary system can lead to three main types of disorder: pneumoconioses, bronchial cancers and most chronic bronchopulmonary diseases. The study of deposition is useful for the prevention, diagnosis and treatment of these illnesses. The air-borne contaminants laid down are cleared by different mechanisms corresponding roughly to distinct anatomical regions. Short-term clearance, known as tracheobronchial (TB) takes place in a few hours, while long-term clearance from the deep lung is much slower: according to the International Radiological Protection Commission, 60% of particles deposited in the bronchiolo-alveolar region take more than 500 days to eliminate. It is useful therefore to known in what proportions the particles are fixed in the tracheobronchial region and on the deep lung. This was the purpose of the present work. The distribution of the deposit between these two regions was measured in 52 subjects having breathed in radioactive particles (indium 111). A functional respiratory study was conducted at the same time to find out whether the two sets of experimental data are related in any way [fr

  15. Expandable metallic stents for tracheobronchial stenoses in esophageal cancer.

    Science.gov (United States)

    Takamori, S; Fujita, H; Hayashi, A; Tayama, K; Mitsuoka, M; Ohtsuka, S; Shirouzu, K

    1996-09-01

    Tracheobronchial stenosis in patients with esophageal cancer can be life threatening. Few reports have discussed use of expandable metallic stents for central airway stenoses in patients with esophageal cancer. Twelve patients with esophageal cancer underwent placement of expandable metallic stents for respiratory distress caused by tracheobronchial stricture. Single or double metallic stents were placed in the stenotic airways under fluoroscopic guidance. Improvement in respiratory symptoms and clinical outcome were assessed. Most stenoses were located in the trachea or the left main bronchus. From one to four expandable metallic stents were placed in each stricture site, with immediate relief of respiratory symptoms in 8 patients. One patient with tracheomalacia in alive 3 years after stent placement and another is alive 6 months after stent insertion. The other 10 patients lived from 10 to 70 days (mean; survival, 35 days) after stent placement. Death was due to progression of disease. Although metallic stents are useful for relieving respiratory distress in patients with advanced esophageal cancer, additional therapies should be considered.

  16. Metallic Stents for Tracheobronchial Pathology Treatment

    International Nuclear Information System (INIS)

    Serrano, Carolina; Laborda, Alicia; Lozano, Juan M.; Caballero, Hugo; Sebastián, Antonio; Lopera, Jorge; Gregorio, Miguel Ángel de

    2013-01-01

    Purpose: To present the 7-year experience of the treatment of benign and malignant tracheobronchial stenoses using metallic stents. Patients and Methods: One hundred twenty-three stents were inserted in 86 patients (74 benign and 12 malignant stenoses). Ninety-seven stents were placed in the trachea and 26 in the bronchi. The procedures were performed under fluoroscopic and flexible bronchoscopic guidance with the patient under light sedation. In cases of severe stenotic lesions or obstructions, laser resection was performed before stent placement. Clinical and functional pulmonary data were recorded before and 3 months after the procedure. Follow-up involved clinical data and radiographic techniques at 48 h and at 1-, 3-, 6-, and 12-month intervals. Results: The technical success was 100 %. Dyspnea disappearance, forced expiratory volume in the first second, and pulmonary functional data improvement was observed in all patients (p < 0.001). Complications were detected in 23 patients (26.7 %). Mean follow-up time was 6.3 ± 1.2 months in patients with malignant lesions and 76.2 ± 2.3 months patients with in benign lesions. By the end of the study, 100 % of patients with malignant pathology and 6.7 % of patients with benign lesions had died. Conclusion: Endoluminal treatment of tracheobronchial stenosis with metallic stents is a therapeutic alternative in patients who are poor candidates for surgery. In unresectable malignant lesions, the benefit of metallic stenting is unquestionable. In benign lesions, the results are satisfactory, but sometimes other interventions are required to treat complications. New stent technology may improve these results

  17. Metallic stents for tracheobronchial pathology treatment.

    Science.gov (United States)

    Serrano, Carolina; Laborda, Alicia; Lozano, Juan M; Caballero, Hugo; Sebastián, Antonio; Lopera, Jorge; de Gregorio, Miguel Ángel

    2013-12-01

    To present the 7-year experience of the treatment of benign and malignant tracheobronchial stenoses using metallic stents. One hundred twenty-three stents were inserted in 86 patients (74 benign and 12 malignant stenoses). Ninety-seven stents were placed in the trachea and 26 in the bronchi. The procedures were performed under fluoroscopic and flexible bronchoscopic guidance with the patient under light sedation. In cases of severe stenotic lesions or obstructions, laser resection was performed before stent placement. Clinical and functional pulmonary data were recorded before and 3 months after the procedure. Follow-up involved clinical data and radiographic techniques at 48 h and at 1-, 3-, 6-, and 12-month intervals. The technical success was 100 %. Dyspnea disappearance, forced expiratory volume in the first second, and pulmonary functional data improvement was observed in all patients (p < 0.001). Complications were detected in 23 patients (26.7 %). Mean follow-up time was 6.3 ± 1.2 months in patients with malignant lesions and 76.2 ± 2.3 months patients with in benign lesions. By the end of the study, 100 % of patients with malignant pathology and 6.7 % of patients with benign lesions had died. Endoluminal treatment of tracheobronchial stenosis with metallic stents is a therapeutic alternative in patients who are poor candidates for surgery. In unresectable malignant lesions, the benefit of metallic stenting is unquestionable. In benign lesions, the results are satisfactory, but sometimes other interventions are required to treat complications. New stent technology may improve these results.

  18. Metallic Stents for Tracheobronchial Pathology Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Serrano, Carolina, E-mail: carolina.serrano@unizar.es [University of Zaragoza, Surgical Pathology Unit, Animal Pathology Department (Spain); Laborda, Alicia, E-mail: alaborda@unizar.es [University of Zaragoza, Minimally Invasive Techniques Research Group (GITMI) (Spain); Lozano, Juan M., E-mail: juamauloz@gmail.com [Marly Clinic, Radiology Department (Colombia); Caballero, Hugo, E-mail: hugocaballero2007@gmail.com [Marly Clinic, Pulmonology Department (Colombia); Sebastian, Antonio, E-mail: antonio.sebastian@ono.es [Lozano Blesa Clinical University Hospital, Pulmonology Department (Spain); Lopera, Jorge, E-mail: lopera@uthscsa.edu [Health Science Center, Interventional Radiology Deparment (United States); Gregorio, Miguel Angel de, E-mail: mgregori@unizar.es [University of Zaragoza, Minimally Invasive Techniques Research Group (GITMI) (Spain)

    2013-12-15

    Purpose: To present the 7-year experience of the treatment of benign and malignant tracheobronchial stenoses using metallic stents. Patients and Methods: One hundred twenty-three stents were inserted in 86 patients (74 benign and 12 malignant stenoses). Ninety-seven stents were placed in the trachea and 26 in the bronchi. The procedures were performed under fluoroscopic and flexible bronchoscopic guidance with the patient under light sedation. In cases of severe stenotic lesions or obstructions, laser resection was performed before stent placement. Clinical and functional pulmonary data were recorded before and 3 months after the procedure. Follow-up involved clinical data and radiographic techniques at 48 h and at 1-, 3-, 6-, and 12-month intervals. Results: The technical success was 100 %. Dyspnea disappearance, forced expiratory volume in the first second, and pulmonary functional data improvement was observed in all patients (p < 0.001). Complications were detected in 23 patients (26.7 %). Mean follow-up time was 6.3 {+-} 1.2 months in patients with malignant lesions and 76.2 {+-} 2.3 months patients with in benign lesions. By the end of the study, 100 % of patients with malignant pathology and 6.7 % of patients with benign lesions had died. Conclusion: Endoluminal treatment of tracheobronchial stenosis with metallic stents is a therapeutic alternative in patients who are poor candidates for surgery. In unresectable malignant lesions, the benefit of metallic stenting is unquestionable. In benign lesions, the results are satisfactory, but sometimes other interventions are required to treat complications. New stent technology may improve these results.

  19. Tracheobronchial calcification in adult health study subjects

    International Nuclear Information System (INIS)

    Fukuya, Tatsuro; Mihara, Futoshi; Kudo, Sho; Russell, W.J.; Delongchamp, R.R.; Vaeth, M.; Hosoda, Yutaka.

    1988-04-01

    Tracheobronchial calcification is reportedly more frequent in women than in men. Ten cases of extensive tracehobronchial calcification were identified on chest radiographs of 1,152 consecutively examined Adult Health Study subjects, for a prevalence of 0.87 %. An additional 51 subjects having this coded diagnosis were identified among 11,758 members of this fixed population sample. Sixty of the 61 subjects were women. The manifestations and extent of this type of calcification and its correlations with clinical and histopathologic features, which have not been previously reported, are described here. (author)

  20. Invasive tracheobronchial aspergillosis in a patient with systemic lupus erythematosus-dermatomyositis overlap syndrome.

    Science.gov (United States)

    Sada, Mitsuru; Saraya, Takeshi; Tanaka, Yasutaka; Sato, Shinji; Wakayama, Megumi; Shibuya, Kazutoshi; Uchiyama, Takashi; Ogata, Hideo; Takizawa, Hajime; Goto, Hajime

    2013-01-01

    A 45-year-old man was referred to our hospital with a 3-month history of dyspnea, polyarthralgia, myalgia and weight loss. He was diagnosed with systemic lupus erythematosus/dermatomyositis overlap syndrome with lung involvement, which presented as organizing pneumonia. However, a bronchoscopic examination revealed the presence of multiple plaque-like white lesions with ulcers on the bronchial membrane, located mainly in the central airway. The pathological specimens obtained from bronchoscopy showed numerous filamentous fungal hyphae that were aggressively invading the bronchial walls, suggesting a diagnosis of invasive tracheobronchial aspergillosis. The present case, along with a review of the literature, demonstrates that invasive tracheobronchial aspergillosis can occur in patients who do not appear to be immunosuppressed. This case of aspergillosis should thus be recognized as an extremely rare presentation of an Aspergillus infection.

  1. Generating Multi-Destination Maps.

    Science.gov (United States)

    Zhang, Junsong; Fan, Jiepeng; Luo, Zhenshan

    2017-08-01

    Multi-destination maps are a kind of navigation maps aimed to guide visitors to multiple destinations within a region, which can be of great help to urban visitors. However, they have not been developed in the current online map service. To address this issue, we introduce a novel layout model designed especially for generating multi-destination maps, which considers the global and local layout of a multi-destination map. We model the layout problem as a graph drawing that satisfies a set of hard and soft constraints. In the global layout phase, we balance the scale factor between ROIs. In the local layout phase, we make all edges have good visibility and optimize the map layout to preserve the relative length and angle of roads. We also propose a perturbation-based optimization method to find an optimal layout in the complex solution space. The multi-destination maps generated by our system are potential feasible on the modern mobile devices and our result can show an overview and a detail view of the whole map at the same time. In addition, we perform a user study to evaluate the effectiveness of our method, and the results prove that the multi-destination maps achieve our goals well.

  2. In vivo detection of plutonium in the tracheobronchial lymph nodes with a fiber-optic coupled scintillator

    International Nuclear Information System (INIS)

    Swinth, K.L.; Park, J.F.; Voelz, G.L.; Ewins, J.H.

    1976-01-01

    An intraesophageal probe was developed for measuring plutonium in the tracheobronchial lymph nodes. The probe uses a fiber-optic coupled NaI(Tl) scintillator as a detector and has a detection limit one-tenth that of a solid-state probe previously used for this measurement. The probe, with a projected sensitivity of 1 cpm/nCi, was used to detect plutonium in the lymph nodes of 11 experimentally exposed dogs. Tests on an accidentally exposed human volunteer yielded positive counts from the lymph nodes from an amount estimated at 7 nCi in the tracheobronchial lymph nodes

  3. Correlative factors for the location of tracheobronchial foreign bodies in infants and children.

    Science.gov (United States)

    Xu, Ying; Feng, Rui-Ling; Jiang, Lan; Ren, Hong-Bo; Li, Qi

    2018-02-01

    This study aims to analyze factors related to the location of tracheobronchial foreign bodies in infants and children, and provide help in the assessment of the disease, surgical risk and prognosis. The clinical data of 1,060 pediatric patients with tracheobronchial foreign bodies diagnosed from January 2015 to December 2015 were retrospectively studied, the association of the location of the foreign bodies with age, gender, granulation formation, chest computed tomography and 3D reconstruction results, preoperative complications, operation time, and hospital stay was analyzed. The location of foreign bodies was not correlated with age, gender, operation time and length of hospital stay, but was correlated to granulation formation, chest computed tomography and 3D reconstruction results, and preoperative complications. The location of foreign bodies was correlated to granulation formation, the location of foreign bodies displayed by chest computed tomography, and preoperative complications.

  4. The role of airway stenting in pediatric tracheobronchial obstruction.

    Science.gov (United States)

    Antón-Pacheco, Juan L; Cabezalí, Daniel; Tejedor, Raquel; López, María; Luna, Carmen; Comas, Juan V; de Miguel, Eduardo

    2008-06-01

    Tracheobronchial obstruction is infrequent in the pediatric age group but it is associated with significant morbidity and mortality. The purpose of this study is to review the results of a single institution experience with endoscopic stent placement in children with benign tracheobronchial obstruction, and with special concern on safety and clinical effectiveness. Twenty-one patients with severe airway stenosing disease in which stent placement was performed between 1993 and 2006. Inclusion criteria according to the clinical status were: failure to wean from ventilation, episode of apnea, frequent respiratory infections (>3 pneumonia/year), and severe respiratory distress. Additional criteria for stent placement were: failure of surgical treatment, bronchomalacia, and tracheomalacia refractory to previous tracheostomy. Selection of the type of stent depended on the site of the lesion, the patient's age, and the stent availability when time of presentation. The following variables were retrospectively evaluated: age, type of obstruction, associated malformations, stent properties, technical and clinical success, complications and related reinterventions, outcome and follow-up period. Thirty-three stents were placed in the trachea (n=18) and/or bronchi (n=15) of 21 patients with a median age of 6 months (range, 9 days-19 years). Etiology of the airway obstruction included severe tracheomalacia and/or bronchomalacia in 19 cases (90%), and postoperative tracheal stenosis in two. Twelve children had a total of 20 balloon-expandable metallic stents placed, and 10 had 13 silicone-type stents (one patient had both). In nine patients (42%) more than one device was placed. Stent positioning was technically successful in all but one patient. Clinical improvement was observed in 18 patients (85%) but complications occurred in five of them (27%). Eight patients died during follow-up but only in one case it was related to airway stenting. Thirteen patients (62%) are alive and

  5. Results of endoscopic surgery and intralesional steroid therapy for airway compromise due to tracheobronchial Wegener's granulomatosis

    Directory of Open Access Journals (Sweden)

    S. A. R. Nouraei

    2008-04-01

    Full Text Available Background: Upper airway compromise due to tracheobronchial stenosis commonly occurs in patients with Wegener's Granulomatosis (WG. There is at present no consensus on the optimal management of this life-threatening condition. Objective: To assess the results of laryngo-tracheo-bronchoscopy, intralesional steroid therapy, laser surgery, and dilatation in managing obstructive tracheobronchial WG. Methods: Records of eighteen previously-untreated stridulous patients with obstructive tracheobronchial WG, treated between 2004 and 2006 were prospectively recorded on an airway database and retrospectively reviewed. Information about patient and lesion characteristics and treatment details were recorded. Treatment progress was illustrated using a timeline plot, and intervention-free intervals were calculated with actuarial analysis. Results: There were nine males and the average age at presentation was 40 (16 years [range 13–74]. There were thirteen patients with tracheal, and five patients with tracheal and bronchial lesions. The average tracheal lesion height was 8 (3 mm, located 23 (9 mm below the glottis. There were 1, 10 and 7 Myer-Cotton grade I, II and III lesions respectively. Mean intervention-free interval following minimally-invasive treatment was 26 (2.8 months. Following endobronchial therapy the median intervention-free interval was 22 months (p>0.8 vs. tracheal lesions. No patient required a tracheostomy or endoluminal stenting. Conclusions: Intralesional steroid therapy and conservative endoluminal surgery is an effective strategy for treating airway compromise due to active tracheal and bronchial WG, obviating the need for airway bypass or stenting. We recommend the combination of endotracheal dilatation, conservative laser surgery and steroid therapy as the standard of care for treating airway compromise due to obstructive tracheobronchial WG.

  6. Temporary placement of metallic stent could lead to long-term benefits for benign tracheobronchial stenosis.

    Science.gov (United States)

    Zhou, Guo-Wu; Huang, Hai-Dong; Sun, Qin-Ying; Xiong, Ye; Li, Qiang; Dong, Yu-Chao; Zhang, Wei

    2015-12-01

    The permanent placement of metallic stent for benign tracheobronchial stenosis (BTS) was controversial. This study was conducted to evaluate the long-term outcomes of temporary placement of metallic stent for BTS. The BTS patients who received temporary placement of retrievable self-expanded metallic stents were included between 2008 and 2011. Pre-stenting and follow-up respiratory status was analyzed. And symptom recurrence-free survival (SRFS) was assessed. A total of 49 stents were successfully temporarily placed in 40 consecutive BTS patients whose etiologies included endobronchial tuberculosis (EBTB) (n=22), post-tracheostomy stenosis (n=10), post-intubation stenosis (n=6) and post radiotherapy stricture (n=2). All stents were removed integrally after a median 18 days' stenting period, without major complications. During the median 27 months follow-up period after stent removal, a total of 22 patients were free of recurrence. And the overall 3-year SRFS rate was 52.0%. According to the etiology, the 3-year SRFS rates were 59.1% and 42.9% in the patients with EBTB and non-EBTB, respectively. Compared with pre-stenting, the follow-up internal diameter of stricture, Hugh-Jones scale, 6-minute walk test (6MWT) and percentage of forced expiratory volume in one second (FEV1%) were significantly improved. Multivariate analysis suggested that granulation tissue growth and tracheobronchial malacia might be independent factors of poor prognosis. Temporary placement of retrievable metallic stent may be an alternative treatment for BTS patients.

  7. Traumatic tracheobronchial stricture treated with the Eder-Puestow dilator.

    Science.gov (United States)

    Erichsen, H G

    1980-09-01

    A case of tracheobronchial stenosis secondary to trauma is presented. Primary reconstruction resulted in stricture in the distal part of the trachea. Resection and anastomosis was followed by restenosis, which had to be treated endoscopically. Endobronchial resections and forceful dilatations with stiff bronchoscopes were done weekly for about 11 months without lasting benefit. After changing to Eder-Puestow dilators, the dilatations could be done at steadily increasing intervals. This method of dilatation was found to be safe, effective and less traumatic.

  8. [Tracheobronchial stents: a retrospective analysis of indications, results and in particular complications].

    Science.gov (United States)

    Tonn, H; Mall, W; Schneider, K-D; Schönhofer, B

    2008-10-01

    Tracheobronchial stents are inserted mainly in cases of malignant and benign airway stenosis. Further indications are esophago-tracheal fistulas, mediastinal fistulas and tracheomalacia. A retrospective analysis was conducted on patients' records, information provided by the general practitioners and relatives of the patients from July 1993 to December 2006 in the Department of Pneumology of the Heidehaus Hospital Hannover (since 6/05 Department of Pneumology and Internal Intensive Care Medicine, Oststadt-Heidehaus Hospital). During the observation period of 13 years a total of 269 stents (177 permanent, 92 temporary) were implanted in 207 patients (1.3 stents per patient). The vast majority of patients (173/207) suffered from an underlying malignancy. About half of the stents were deployed in the trachea. The median length of placement was 116 days in patients with malignancies and 313 days in patients with benign diseases. In about 40 % of the patients notable complications were observed which were directly or indirectly associated with the stents. These findings show the importance of a critical indication for stent implantation. In benign diseases a stent can remain for years inside the tracheobronchial system, if it is well tolerated in the beginning. In malignant diseases the result depends decisively on the stage of the tumour: has the stent been implanted before any other tumour therapy is started or is it an end-stage tumor with no other therapeutic option? In general, complications of stents occur quite frequently. The analysis of stent data leads to some aspects for the prevention of stent-related complications. There should be a strict indication and appropriate choice of stent material. Nevertheless, there remains an ethical dilemma in patients with end-stage disease as to whether to implant a stent or to do nothing against the tumor, because the benefit immediately after stent insertion vanishes with progression of the tumour, so causing extra

  9. Thermodynamic analysis of a solar-based multi-generation system with hydrogen production

    International Nuclear Information System (INIS)

    Ozturk, Murat; Dincer, Ibrahim

    2013-01-01

    Thermodynamic analysis of a renewable-based multi-generation energy production system which produces a number of outputs, such as power, heating, cooling, hot water, hydrogen and oxygen is conducted. This solar-based multi-generation system consists of four main sub-systems: Rankine cycle, organic Rankine cycle, absorption cooling and heating, and hydrogen production and utilization. Exergy destruction ratios and rates, power or heat transfer rates, energy and exergy efficiencies of the system components are carried out. Some parametric studies are performed in order to examine the effects of varying operating conditions (e.g., reference temperature, direct solar radiation and receiver temperature) on the exergy efficiencies of the sub-systems as well as the whole system. The solar-based multi-generation system which has an exergy efficiency of 57.35%, is obtained to be higher than using these sub-systems separately. The evaluation of the exergy efficiency and exergy destruction for the sub-systems and the overall system show that the parabolic dish collectors have the highest exergy destruction rate among constituent parts of the solar-based multi-generation system, due to high temperature difference between the working fluid and collector receivers. -- Highlights: ► Development of a new multi-generation system for solar-based hydrogen production. ► Investigation of exergy efficiencies and destructions in each process of the system. ► Evaluation of varying operating conditions on the exergy destruction and efficiency

  10. Treatment of tracheobronchial stenosis with a self-expandable metallic stents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Soo; Jeon, Seok Chol; Choi, Chul Seung; Choi, Yo Won; Hahm, Chang Kok [College of Medicine, Hanyang University, Seoul (Korea, Republic of)

    1994-07-15

    We analysed the role of modified Gianturco self-expandable stents in the treatment of tracheobronchial stenosis in 13 patients. We inserted modified Gianturco self-expandable stents under the fluoroscopic and bronchoscopic guidance. There were stenosis in the trachea(n=2), the right main bronchus(n=2), and the left main bronchus(n=9). The causes of the stenosis were endobronchial tuberculosis(n=10), intubation granuloma(n=1), restenosis after surgical reconstruction(n=2). Dyspnea or wheezing was improved within 1 or 2 days following the procedure. There were 32% and 22% respective increase in average FEV1 and FVC. Lung perfusion scan showed 9.6% increase of perfusion in the involved lung. No complications related to the procedure were encountered. During follow-up period of up to 31 months, 2 patients showed tracheal or bronchial restenosis, at 3 and 6 months, retrospectively. There was a distal migration of the stents in one case. During the follow up period after stent insertion, improvement of the obstructive changes and dyspnea persisted in 10 out of 13 patients. The modified Gianturco self-expandable metallic stents may be a good choice for the treatment of tracheobronchial stenosis, either as a primary treatment, or when the reconstruction failed.

  11. Multi-Threaded DNA Tag/Anti-Tag Library Generator for Multi-Core Platforms

    Science.gov (United States)

    2009-05-01

    base pair)  Watson ‐ Crick  strand pairs that bind perfectly within pairs, but poorly across pairs. A variety  of  DNA  strand hybridization metrics...AFRL-RI-RS-TR-2009-131 Final Technical Report May 2009 MULTI-THREADED DNA TAG/ANTI-TAG LIBRARY GENERATOR FOR MULTI-CORE PLATFORMS...TYPE Final 3. DATES COVERED (From - To) Jun 08 – Feb 09 4. TITLE AND SUBTITLE MULTI-THREADED DNA TAG/ANTI-TAG LIBRARY GENERATOR FOR MULTI-CORE

  12. Regional deposition of thoron progeny in models of the human tracheobronchial tree

    Energy Technology Data Exchange (ETDEWEB)

    Smith, S.M.; Cheng, Yung-Sung; Yeh, Hsu-Chi

    1995-12-01

    Models of the human tracheobronchial tree have been used to determine total and regional aerosol deposition of inhaled particles. Particle sizes measured in these studies have all been > 40 nm in diameter. The deposition of aerosols < 40 nm in diameter has not been measured. Particles in the ultrafine aerosol size range include some combustion aerosols and indoor radon progeny. Also, the influence of reduced lung size and airflow rates on particle deposition in young children has not been determined. With their smaller lung size and smaller minute volumes, children may be at increased risk from ultrafine pollutants. In order to accurately determine dose of inhaled aerosols, the effects of particle size, minute volume, and age at exposure must be quantified. The purpose of this study was to determine the deposition efficiency of ultrafine aerosols smaller than 40 nm in diameter in models of the human tracheobronchia tree. This study demonstrates that the deposition efficiency of aerosols in the model of the child`s tracheobronchial tree may be slightly higher than in the adult models.

  13. Regional deposition of thoron progeny in models of the human tracheobronchial tree

    International Nuclear Information System (INIS)

    Smith, S.M.; Cheng, Yung-Sung; Yeh, Hsu-Chi.

    1995-01-01

    Models of the human tracheobronchial tree have been used to determine total and regional aerosol deposition of inhaled particles. Particle sizes measured in these studies have all been > 40 nm in diameter. The deposition of aerosols < 40 nm in diameter has not been measured. Particles in the ultrafine aerosol size range include some combustion aerosols and indoor radon progeny. Also, the influence of reduced lung size and airflow rates on particle deposition in young children has not been determined. With their smaller lung size and smaller minute volumes, children may be at increased risk from ultrafine pollutants. In order to accurately determine dose of inhaled aerosols, the effects of particle size, minute volume, and age at exposure must be quantified. The purpose of this study was to determine the deposition efficiency of ultrafine aerosols smaller than 40 nm in diameter in models of the human tracheobronchia tree. This study demonstrates that the deposition efficiency of aerosols in the model of the child's tracheobronchial tree may be slightly higher than in the adult models

  14. Treatment of Benign and Malignant Tracheobronchial Obstruction with Metal Wire Stents: Experience with a Balloon-Expandable and a Self-Expandable Stent Type

    International Nuclear Information System (INIS)

    Rieger, Johannes; Hautmann, Hubert; Linsenmaier, Ulrich; Weber, Cristoph; Treitl, Markus; Huber, R.M.; Pfeifer, Klaus-Juergen

    2004-01-01

    Over the last few years various types of metal wire stents have been increasingly employed in the treatment of both malignant and benign tracheobronchial obstruction. To date, however, few studies have investigated the in vivo properties of different stent types. We implanted 26 balloon-expandable tantalum Strecker stents (18 patients) and 18 self-expandable Wallstents (16 patients) into the tracheobronchial system of 30 patients with combined stenting in 4 patients. Mean age was 51 years (range: 0.5-79 years). Malignant disease was present in 23 patients, benign disease in seven patients. Both patients and individual stents were monitored clinically and radiographically. The probability of stents remaining within the tracheobronchial system, and of their remaining undislocated and uncompressed was calculated using Kaplan-Meier analysis for both stent types. Average stent follow-up time was 112 days until explantation and 115 days until patients' death or discharge. Kaplan-Meier analysis revealed a higher probability for the Wallstent to remain within the tracheobronchial system. Dislocation and compression occurred more rarely. Explantation, however, if desired, was more difficult compared to the Strecker stent. The Wallstent also led to the formation of granulation tissue, especially at the proximal stent end, frequently requiring reintervention. Both stent types proved to be effective therapeutic options in the management of obstructive tracheobronchial disease. The mechanical properties of the Strecker stent seem to be less favorable compared to the Wallstent but removal is easy. For benign disease, however, the Wallstent reveals limitations due to significant side effects

  15. Investigation on magnetoacoustic signal generation with magnetic induction and its application to electrical conductivity reconstruction

    International Nuclear Information System (INIS)

    Ma Qingyu; He Bin

    2007-01-01

    A theoretical study on the magnetoacoustic signal generation with magnetic induction and its applications to electrical conductivity reconstruction is conducted. An object with a concentric cylindrical geometry is located in a static magnetic field and a pulsed magnetic field. Driven by Lorentz force generated by the static magnetic field, the magnetically induced eddy current produces acoustic vibration and the propagated sound wave is received by a transducer around the object to reconstruct the corresponding electrical conductivity distribution of the object. A theory on the magnetoacoustic waveform generation for a circular symmetric model is provided as a forward problem. The explicit formulae and quantitative algorithm for the electrical conductivity reconstruction are then presented as an inverse problem. Computer simulations were conducted to test the proposed theory and assess the performance of the inverse algorithms for a multi-layer cylindrical model. The present simulation results confirm the validity of the proposed theory and suggest the feasibility of reconstructing electrical conductivity distribution based on the proposed theory on the magnetoacoustic signal generation with magnetic induction

  16. Long-term tolerance of airway silicone stent in patients with post-tuberculosis tracheobronchial stenosis.

    Science.gov (United States)

    Verma, Akash; Um, Sang-Won; Koh, Won-Jung; Suh, Gee Young; Chung, Man Pyo; Kwon, O Jung; Kim, Hojoong

    2012-01-01

    Surgery is a well-recognized modality of treatment for benign tracheobronchial stenosis. However, in some benign disease groups, such as tuberculosis, sarcoidosis, war gas exposure, and inhalation burns, multiplicity of involvement or long length of stenosed segment heightens surgical challenge. We investigated the outcomes and long-term tolerability of the Natural stent (N-stent) in such patients with post-tuberculosis tracheobronchial stenosis. A retrospective review was done for 17 patients who underwent silicone stenting (N-stent) for post-tuberculosis tracheobronchial stenosis during January 2000-December 2003 but needed persistent stent placement and still require the stent. Significant increase in the ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC), expressed as FEV1%, as well as in forced percentual vital capacity (FVC%) (Δ24% and Δ11%, respectively) in the short term and sustained increase in the FEV1% and FVC% (Δ26.5% and Δ16.5%, respectively) in the long term were noted at a median (range) interval of 1 (0.5-72) month and 72 (12-114) months, respectively, along with symptomatic relief. No procedure-related death occurred. Stent-related late complications included granulation tissue formation (76%), migration (70%), and mucostasis (17%). The median duration for which N-stents were tolerated was 7.9 (range, 3-11) years. N-stents are well-tolerated for a prolonged period. Stent-related complications occur, but are easily managed. These results might carry medical implications for those who have airway lesions difficult to correct surgically.

  17. Expandable metallic stent: experimental and clinical experience in tracheobronchial tree

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ho Young; Lee, Sang Young; Chung, Jin Young; Han, Young Min; Kim, Jong Soo; Choi, Ki Chul; Hong, Ki Whan; Rhee, Yang Kun [Chonbuk National University Medical School, Jeonju (Korea, Republic of)

    1991-05-15

    To maintain or reestablish an adequate airway in a patient with tracheobronchial narrowing coming from various causes, we constructed self-expanding metallic stents the same way Gianturco did, using them in 2 patients after an experimental study with rabbits. Twenty stents (10mm in diameter fully expanded and 20mm in length) were introduced into the trachea or bronchi of 10 Newzealand rabbits (weight, 2.5-3.0kg) through a 8.5 French Teflon sheath. No difficulties were encountered in the placement of the stents. At follow-up (4-12 weeks), no stent showed migration. Three rabbits died of pneumonia or bronchial perforation. Histologically, mucosal inflammation was noted at the sites of stent placement, and stent wires were covered by proliferated epithelium with intact cilia. During the last 4 months, 2 stents were used in 2 patients, one in a patient with endobronchial tuberculosis (3.0cm in length and 1.0cm in diameter fully expanded) and the other (3.0cm in length and 1.5cm in diameter) in a patient with a subglottic mass. In both patients the stents were successfully placed. Just after the placement of the stents dyspnea subsided in both patients, and there was no mortality or morbidity. These stents seem to be effective in the treatment of tracheobronchial stenosis, tracheomalacia, and airway collapse following tracheal reconstruction.

  18. Expandable metallic stent: experimental and clinical experience in tracheobronchial tree

    International Nuclear Information System (INIS)

    Song, Ho Young; Lee, Sang Young; Chung, Jin Young; Han, Young Min; Kim, Jong Soo; Choi, Ki Chul; Hong, Ki Whan; Rhee, Yang Kun

    1991-01-01

    To maintain or reestablish an adequate airway in a patient with tracheobronchial narrowing coming from various causes, we constructed self-expanding metallic stents the same way Gianturco did, using them in 2 patients after an experimental study with rabbits. Twenty stents (10mm in diameter fully expanded and 20mm in length) were introduced into the trachea or bronchi of 10 Newzealand rabbits (weight, 2.5-3.0kg) through a 8.5 French Teflon sheath. No difficulties were encountered in the placement of the stents. At follow-up (4-12 weeks), no stent showed migration. Three rabbits died of pneumonia or bronchial perforation. Histologically, mucosal inflammation was noted at the sites of stent placement, and stent wires were covered by proliferated epithelium with intact cilia. During the last 4 months, 2 stents were used in 2 patients, one in a patient with endobronchial tuberculosis (3.0cm in length and 1.0cm in diameter fully expanded) and the other (3.0cm in length and 1.5cm in diameter) in a patient with a subglottic mass. In both patients the stents were successfully placed. Just after the placement of the stents dyspnea subsided in both patients, and there was no mortality or morbidity. These stents seem to be effective in the treatment of tracheobronchial stenosis, tracheomalacia, and airway collapse following tracheal reconstruction

  19. Particle deposition in human and canine tracheobronchial casts: Annual progress report

    International Nuclear Information System (INIS)

    Cohen, B.S.

    1987-01-01

    This work measures deposition patterns and efficiencies of aerosols within realistic, physical models of the tracheobronchial airways of humans and experimental animals over a range of particle sizes from 0.01 to 1.0 μm, for a variety of respiratory modes and rates. Full morphometric and flow distribution measurements were completed on casts of human and canine tracheobronchial airways, which extend from just below the larynx to airways 1 mm in diameter. They show basic similarities in the distribution of airflow, but also species differences which must be considered. The distribution of airflow was measured for minute volumes equivalent to 6, 11, 17 and 22 L min -1 for the human and 3, 6, 8 and 11 L min -1 for the canine for both constant and pulsatile inspiratory flow. Inertance was found to carry more of the flow to airways of the lower lobes at higher flow rates. Basic differences in airway branching pattern result in a more distinct change in airflow distribution as flow rate changes for the canine cast as compared with the human cast. These differences will contribute to differing patterns of mass transfer of inhaled particles in central airways of the two species. 8 refs., 2 figs., 5 tabs

  20. Risk factors for granuloma formation in children induced by tracheobronchial foreign bodies.

    Science.gov (United States)

    Huang, Zhenghua; Zhou, Ai; Zhang, Jianya; Xie, Lisheng; Li, Qi

    2015-12-01

    The aim of this study was to analyze the risk factors for granuloma formation caused by plant-based tracheobronchial foreign bodies in children, and investigate the underlying pathogenesis. In this retrospective analysis of 153 cases with tracheobronchial foreign bodies (peanuts and watermelon seeds), 35 cases of granuloma formation as granulation group (G), and 118 cases of no granuloma formation as non-granulation group (NG) were studied. Clinical data pertaining to sex (S), age (A), foreign body surface smoothness (SF), foreign body shape (SH), foreign body oil release state (O), the location of foreign bodies (L), and foreign body retention time (T) were collected for statistical analysis. Univariate analysis showed no significant difference between the two groups (G and NG) with respect to S, A, SH and L. Significant factors based on univariate analysis included SF, O and T. Multivariate logistic regression analysis revealed that SF and T were independent risk factors associated with development of granuloma. SF, O and T had relationship with the granuloma formation. Local trauma caused by an irregular and sharp foreign body, and extended period of time represent the main factors causing granuloma formation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Multi generations in the workforce: Building collaboration

    Directory of Open Access Journals (Sweden)

    Vasanthi Srinivasan

    2012-03-01

    Full Text Available Organisations the world over in today's rapid growth context are faced with the challenge of understanding a multi-generational workforce and devising policies and processes to build collaboration between them. In its first part, this article synthesises the literature on generational studies, with emphasis on the definition of generations and the characteristics of the generational cohorts. It emphasises that such studies are embedded in the socio-economic-cultural-context and India-specific scholarship must take into account the demographic and economic variations across the country. It then discusses the challenges of multi-generations in the Indian workforce, their impact on leadership styles and managerial practices, and the task of building inter-generational collaboration with an eminent panel of practitioners and researchers.

  2. Evaluation of Enhanced Condensational Growth (ECG) for Controlled Respiratory Drug Delivery in a Mouth-Throat and Upper Tracheobronchial Model

    Science.gov (United States)

    Hindle, Michael; Longest, P. Worth

    2010-01-01

    Purpose The objective of this study is to evaluate the effects of enhanced condensational growth (ECG), as a novel inhalation drug delivery method, on nano-aerosol deposition in a mouth-throat (MT) and upper tracheobronchial (TB) model using in vitro experiments and computational fluid dynamics (CFD) simulations. Methods Separate streams of nebulized nano-aerosols and saturated humidified air (39°C—ECG; 25°C—control) were combined as they were introduced into a realistic MT-TB geometry. Aerosol deposition was determined in the MT, generations G0–G2 (trachea—lobar bronchi) and G3–G5 and compared to CFD simulations. Results Using ECG conditions, deposition of 560 and 900 nm aerosols was low in the MT region of the MT-TB model. Aerosol drug deposition in the G0–G2 and G3–G5 regions increased due to enhanced condensational growth compared to control. CFD-predicted depositions were generally in good agreement with the experimental values. Conclusions The ECG platform appears to offer an effective method of delivering nano-aerosols through the extrathoracic region, with minimal deposition, to the tracheobronchial airways and beyond. Aerosol deposition is then facilitated as enhanced condensational growth increases particle size. Future studies will investigate the effects of physio-chemical drug properties and realistic inhalation profiles on ECG growth characteristics. PMID:20454837

  3. Multi-objective optimization for generating a weighted multi-model ensemble

    Science.gov (United States)

    Lee, H.

    2017-12-01

    Many studies have demonstrated that multi-model ensembles generally show better skill than each ensemble member. When generating weighted multi-model ensembles, the first step is measuring the performance of individual model simulations using observations. There is a consensus on the assignment of weighting factors based on a single evaluation metric. When considering only one evaluation metric, the weighting factor for each model is proportional to a performance score or inversely proportional to an error for the model. While this conventional approach can provide appropriate combinations of multiple models, the approach confronts a big challenge when there are multiple metrics under consideration. When considering multiple evaluation metrics, it is obvious that a simple averaging of multiple performance scores or model ranks does not address the trade-off problem between conflicting metrics. So far, there seems to be no best method to generate weighted multi-model ensembles based on multiple performance metrics. The current study applies the multi-objective optimization, a mathematical process that provides a set of optimal trade-off solutions based on a range of evaluation metrics, to combining multiple performance metrics for the global climate models and their dynamically downscaled regional climate simulations over North America and generating a weighted multi-model ensemble. NASA satellite data and the Regional Climate Model Evaluation System (RCMES) software toolkit are used for assessment of the climate simulations. Overall, the performance of each model differs markedly with strong seasonal dependence. Because of the considerable variability across the climate simulations, it is important to evaluate models systematically and make future projections by assigning optimized weighting factors to the models with relatively good performance. Our results indicate that the optimally weighted multi-model ensemble always shows better performance than an arithmetic

  4. High energy multi-cycle terahertz generation

    International Nuclear Information System (INIS)

    Ahr, Frederike Beate

    2017-10-01

    Development of compact electron accelerators and free-electron lasers requires novel acceleration schemes at shorter driving wavelengths. The Axsis project seeks to develop terahertz based electron acceleration as well as the high energy terahertz sources required. This thesis explores the methods and optical material required for the generation of highenergy multi-cycle terahertz pulses. Two experimental concepts to generate high energy terahertz radiation are presented. In addition the theoretical background and the optical properties of pertinent optical materials in the terahertz range are discussed. Investigations of the materials are performed with a terahertz time domain spectrometer and a Fourier transform infrared spectrometer. The nonlinear optical crystal lithium niobate as well as other crystals suitable for the terahertz generation and in addition polymers and other radiation attenuators are characterized in the range from 0.2 to 1 THz. The theory describing the generation of narrowband terahertz radiation is evaluated. The experimental setups to generate terahertz radiation and to characterize its properties are described. The specific crystals - periodically poled lithium niobate (PPLN) - used in the experiments to generate the multi-cycle terahertz radiation are examined to determine e.g. the poling period. The first experimental concept splits the ultra fast, broadband pump pulses into a pulse train in order to pump the PPLN at a higher fluence while increasing the damage limit. The measurements confirm that a pulse train of ultra short, broadband pump pulses increases not only the terahertz energy but also the energy conversion efficiency. The second experimental concept utilizes chirped and delayed infrared laser pulses. This pulse format makes it possible to pump the crystal with high energy pulses resulting in high energy terahertz radiation. The concept is optimized to reach energies up to 127 μJ exceeding the existing results of narrowband

  5. High energy multi-cycle terahertz generation

    Energy Technology Data Exchange (ETDEWEB)

    Ahr, Frederike Beate

    2017-10-15

    Development of compact electron accelerators and free-electron lasers requires novel acceleration schemes at shorter driving wavelengths. The Axsis project seeks to develop terahertz based electron acceleration as well as the high energy terahertz sources required. This thesis explores the methods and optical material required for the generation of highenergy multi-cycle terahertz pulses. Two experimental concepts to generate high energy terahertz radiation are presented. In addition the theoretical background and the optical properties of pertinent optical materials in the terahertz range are discussed. Investigations of the materials are performed with a terahertz time domain spectrometer and a Fourier transform infrared spectrometer. The nonlinear optical crystal lithium niobate as well as other crystals suitable for the terahertz generation and in addition polymers and other radiation attenuators are characterized in the range from 0.2 to 1 THz. The theory describing the generation of narrowband terahertz radiation is evaluated. The experimental setups to generate terahertz radiation and to characterize its properties are described. The specific crystals - periodically poled lithium niobate (PPLN) - used in the experiments to generate the multi-cycle terahertz radiation are examined to determine e.g. the poling period. The first experimental concept splits the ultra fast, broadband pump pulses into a pulse train in order to pump the PPLN at a higher fluence while increasing the damage limit. The measurements confirm that a pulse train of ultra short, broadband pump pulses increases not only the terahertz energy but also the energy conversion efficiency. The second experimental concept utilizes chirped and delayed infrared laser pulses. This pulse format makes it possible to pump the crystal with high energy pulses resulting in high energy terahertz radiation. The concept is optimized to reach energies up to 127 μJ exceeding the existing results of narrowband

  6. A review of cases of tracheobronchial foreign bodies in children

    International Nuclear Information System (INIS)

    Asai, Masatsugu; Adachi, Yuichi; Nakagawa, Hajime

    2007-01-01

    Twenty-three children with tracheobronchial foreign bodies were statistically studied. The number of cases under 3 years of age was 16 (70%). The male-female ratio was 1.9:1. In 19 cases, the foreign bodies were radiolucent. Within these 19 cases, 12 cases involved peanuts. In 4 cases, the foreign bodies were radiopaque. Eight patients underwent extirpation more than 1 week after inhalation because of diagnostic delay. Some of these cases showed granulation in the bronchus and other complications. For early diagnosis, education is necessary not only for parents but also for general physicians. Foreign bodies were lodged in the right bronchus in 11 cases, left bronchus in 11 cases, and trachea in 1 case. Chest X-ray was performed in all patients. Auxiliary examinations performed were lung perfusion scintigraphy (n=9), CT scan (n=8) and MR imaging (n=4). Lung perfusion scintigraphy and CT scan are easy to perform and seemed to be effective for diagnosis. Observation of the trachea and bronchus using a flexible fiberoptic bronchoscope before insertion of rigid ventilation bronchoscopy (VBS) is useful for avoiding subglottic swelling. Furthermore, it is helpful for suctioning sputum and for collecting useful information on the airway before using VBS. For extirpation, we used VBS in 20 cases and a flexible fiberoptic bronchoscope in 3 cases. Sometimes, after extirpation patients suffer respiratory disturbance from complications such as pneumonia. Cooperation of otolaryngologists and pediatricians as a team is necessary for treatment of tracheobronchial foreign bodies. (author)

  7. One-stoma carinoplasty: right upper sleeve lobectomy with hemicarinectomy for resection of right-tracheobronchial-angle tumors.

    Science.gov (United States)

    Kaya, Seyda Ors; Sevinc, Serpil; Ceylan, Kenan Can; Usluer, Ozan; Unsal, Saban

    2013-01-01

    Tracheobronchial-angle tumors involve the right main bronchus, the right upper lobar bronchus, and the lateral wall of the lower trachea. Resecting these tumors is one of the most complex procedures in thoracic surgery. In cases of high-caliber mismatch, the selection of a suitable anastomotic technique can be challenging. We found that our use of a one-stoma carinoplasty technique overcame high-caliber mismatch after the resection of these tumors. From 2009 through 2012, 8 men (mean age, 59 ± 6.2 yr; range, 46-66 yr) underwent complete resection of non-small-cell right-tracheobronchial-angle tumors at our institution. In every case, right upper sleeve lobectomy, wedge carinal resection, and one-stoma carinoplasty were applied. After tumor resection, one patient with hemoptysis and bronchopleural fistula underwent a completion pneumonectomy and died 10 days postoperatively. Bronchoscopy was necessary in 2 patients who had atelectasis in the contralateral lung. At a mean follow-up duration of 19.43 ± 8.4 months (range, 0.2-27.1 mo), 6 patients were alive and free of disease. We conclude that our one-stoma carinoplasty technique enables the resection of tumors at the right tracheobronchial angle, with acceptable morbidity and mortality rates. This method saves the unaffected part of the ipsilateral lung and can overcome high-caliber mismatch. Because of these and other advantages, we suggest that using our method first might preclude having to perform a right carinal sleeve pneumonectomy or using Barclay's method.

  8. Tracheobronchial Amyloidosis Mimicking Tracheal Tumor

    Directory of Open Access Journals (Sweden)

    Elif Tanrıverdi

    2016-01-01

    Full Text Available Tracheobronchial amyloidosis is a rare presentation and accounts for about 1% of benign tumors in this area. The diagnosis of disease is delayed due to nonspecific pulmonary symptoms. Therapeutic approaches are required to control progressive pulmonary symptoms for most of the patients. Herein, we report a case of a 68-year-old man admitted with progressive dyspnea to our institution for further evaluation and management. He was initially diagnosed with and underwent management for bronchial asthma for two years but had persistent symptoms despite optimal medical therapy. Pulmonary computed tomography scan revealed severe endotracheal stenosis. Bronchoscopy was performed and showed endotracheal mass obstructing 70% of the distal trachea and mimicking a neoplastic lesion. The mass was successfully resected by mechanical resection, argon plasma coagulation (APC, and Nd-YAG laser during rigid bronchoscopy. Biopsy materials showed deposits of amorphous material by hematoxylin and eosin staining and these deposits were selectively stained with Congo Red. Although this is a rare clinical condition, this case indicated that carrying out a bronchoscopy in any patient complaining of atypical bronchial symptoms or with uncontrolled asthma is very important.

  9. Generation of multi-wing chaotic attractor in fractional order system

    International Nuclear Information System (INIS)

    Zhang Chaoxia; Yu Simin

    2011-01-01

    Highlights: → We investigate a novel approach for generating multi-wing chaotic attractors. → We introduce a fundamental fractional differential nominal linear system. → A proper nonlinear state feedback controller is designed. → The controlled system can generate fractional-order multi-wing chaotic attractors. - Abstract: In this paper, a novel approach is proposed for generating multi-wing chaotic attractors from the fractional linear differential system via nonlinear state feedback controller equipped with a duality-symmetric multi-segment quadratic function. The main idea is to design a proper nonlinear state feedback controller by using four construction criterions from a fundamental fractional differential nominal linear system, so that the controlled fractional differential system can generate multi-wing chaotic attractors. It is the first time in the literature to report the multi-wing chaotic attractors from an uncoupled fractional differential system. Furthermore, some basic dynamical analysis and numerical simulations are also given, confirming the effectiveness of the proposed method.

  10. Solitary Tracheobronchial Papilloma: Cytomorphology and ancillary studies with histologic correlation.

    Science.gov (United States)

    Lang, Tee U; Khalbuss, Walid E; Monaco, Sara E; Pantanowitz, Liron

    2011-03-03

    Solitary tracheobronchial papilloma (STBP) is a rare benign tumor that primarily involves the tracheobronchial tree. Human papilloma virus (HPV) infection is associated with dysplasia and a high risk of carcinoma in these lesions. The cytomorphology of STBP is not well established in the literature. Our aim is to characterize the cytomorphologic features of STBP, with histologic correlation in a series of 6 patients - 4 males and 2 females - with a mean age of 67 years (range, 53-88 years). There were 5 biopsy-proven squamous papillomas and 1 glandular papilloma. On surgical biopsy, squamous papillomas exhibited cytological atypia (4 graded mild and 1 graded moderate with focal severe dysplasia), surface erosion, and inflammation. Cytology specimens available for review included a combination of 4 fine-needle aspirations (FNAs), 2 bronchoalveolar lavages and 2 (of 3) bronchial brushings. Cytologic findings associated with squamous papillomas included atypical squamous cells and rare squamous cell resembling koilocyte in 1 bronchial brushing. Sheets of squamous cells were identified in another specimen. Several cases had a prominent background of acute inflammation, and candida was present in 1 specimen. HPV in-situ hybridization was positive in 1 case and negative in 2 cases. A p16 immunocytochemical stain performed on 1 cell block was negative. In conclusion, although STBP is a rare neoplasm, these cases may be encountered in respiratory cytology samples. FNA of papillomas yields fewer lesional cells compared to exfoliative samples. These lesions may be mistaken in cytology specimens for squamous cell carcinoma, squamous-lined cavitary lesions, an infectious (fungal) process, reactive squamous metaplasia, or oral contamination.

  11. Removal of Retrievable Self-Expandable Metallic Tracheobronchial Stents: An 18-Year Experience in a Single Center

    International Nuclear Information System (INIS)

    Park, Jung-Hoon; Kim, Pyeong Hwa; Shin, Ji Hoon; Tsauo, Jiaywei; Kim, Min Tae; Cho, Young Chul; Kim, Jin Hyoung; Song, Ho-Young

    2016-01-01

    PurposeThe purpose of the study was to retrospectively evaluate the technical outcomes of removal of retrievable self-expandable metallic stents (REMSs) and identify predictors of technical failure in 81 patients with benign and malignant tracheobronchial strictures.Materials and MethodsA total of 98 REMSs were removed under fluoroscopic guidance in 81 patients with benign (n = 48) or malignant (n = 33) tracheobronchial strictures. Primary and secondary technical success rates and complication rate were evaluated. Technical outcomes with regard to underlying diseases were also evaluated. Logistic regression models were constructed to identify predictors of primary technical success.ResultsPrimary and secondary technical success rates were 86.7 and 94.9 %, respectively. Stent removal-related complication rate was 7.1 % (7/98) and all were bleeding after stent removal. All bleeding complications were minor and managed conservatively. Primary technical success rate for benign strictures was significantly lower compared with that for malignant strictures (80.9 vs. 97.1 %, P = 0.029), but secondary technical success rate (93.7 vs. 97.1 %, P = 0.652) did not differ between the two groups. Granulation tissue formation was identified as an independent predictor of primary technical success (odds ratio 0.249, 95 % CI 0.071–0.874, P = 0.030).ConclusionRemoval of REMSs in patients with benign and malignant tracheobronchial strictures is safe and technically feasible. Bronchoscopic guidance may be required when the removal using a hook wire fails. The presence of granulation tissue was the negative predictor of primary technical success.

  12. Removal of Retrievable Self-Expandable Metallic Tracheobronchial Stents: An 18-Year Experience in a Single Center

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jung-Hoon; Kim, Pyeong Hwa; Shin, Ji Hoon, E-mail: jhshin@amc.seoul.kr; Tsauo, Jiaywei; Kim, Min Tae; Cho, Young Chul; Kim, Jin Hyoung; Song, Ho-Young [University of Ulsan College of Medicine, Departments of Radiology and Research Institute of Radiology, Asan Medical Center (Korea, Republic of)

    2016-11-15

    PurposeThe purpose of the study was to retrospectively evaluate the technical outcomes of removal of retrievable self-expandable metallic stents (REMSs) and identify predictors of technical failure in 81 patients with benign and malignant tracheobronchial strictures.Materials and MethodsA total of 98 REMSs were removed under fluoroscopic guidance in 81 patients with benign (n = 48) or malignant (n = 33) tracheobronchial strictures. Primary and secondary technical success rates and complication rate were evaluated. Technical outcomes with regard to underlying diseases were also evaluated. Logistic regression models were constructed to identify predictors of primary technical success.ResultsPrimary and secondary technical success rates were 86.7 and 94.9 %, respectively. Stent removal-related complication rate was 7.1 % (7/98) and all were bleeding after stent removal. All bleeding complications were minor and managed conservatively. Primary technical success rate for benign strictures was significantly lower compared with that for malignant strictures (80.9 vs. 97.1 %, P = 0.029), but secondary technical success rate (93.7 vs. 97.1 %, P = 0.652) did not differ between the two groups. Granulation tissue formation was identified as an independent predictor of primary technical success (odds ratio 0.249, 95 % CI 0.071–0.874, P = 0.030).ConclusionRemoval of REMSs in patients with benign and malignant tracheobronchial strictures is safe and technically feasible. Bronchoscopic guidance may be required when the removal using a hook wire fails. The presence of granulation tissue was the negative predictor of primary technical success.

  13. Removal of Retrievable Self-Expandable Metallic Tracheobronchial Stents: An 18-Year Experience in a Single Center.

    Science.gov (United States)

    Park, Jung-Hoon; Kim, Pyeong Hwa; Shin, Ji Hoon; Tsauo, Jiaywei; Kim, Min Tae; Cho, Young Chul; Kim, Jin Hyoung; Song, Ho-Young

    2016-11-01

    The purpose of the study was to retrospectively evaluate the technical outcomes of removal of retrievable self-expandable metallic stents (REMSs) and identify predictors of technical failure in 81 patients with benign and malignant tracheobronchial strictures. A total of 98 REMSs were removed under fluoroscopic guidance in 81 patients with benign (n = 48) or malignant (n = 33) tracheobronchial strictures. Primary and secondary technical success rates and complication rate were evaluated. Technical outcomes with regard to underlying diseases were also evaluated. Logistic regression models were constructed to identify predictors of primary technical success. Primary and secondary technical success rates were 86.7 and 94.9 %, respectively. Stent removal-related complication rate was 7.1 % (7/98) and all were bleeding after stent removal. All bleeding complications were minor and managed conservatively. Primary technical success rate for benign strictures was significantly lower compared with that for malignant strictures (80.9 vs. 97.1 %, P = 0.029), but secondary technical success rate (93.7 vs. 97.1 %, P = 0.652) did not differ between the two groups. Granulation tissue formation was identified as an independent predictor of primary technical success (odds ratio 0.249, 95 % CI 0.071-0.874, P = 0.030). Removal of REMSs in patients with benign and malignant tracheobronchial strictures is safe and technically feasible. Bronchoscopic guidance may be required when the removal using a hook wire fails. The presence of granulation tissue was the negative predictor of primary technical success.

  14. Interdisciplinary interventional therapy for tracheobronchial stenosis with modern metal net stents; Interdisziplinaere interventionelle Therapie tracheobronchialer Stenosen mit modernen Metallmaschenstents

    Energy Technology Data Exchange (ETDEWEB)

    Rieger, J.; Linsenmaier, U.; Fedorowski, A.; Pfeifer, K.J. [Ludwig-Maximilians-Universitaet Muenchen (Germany). Inst. fuer Klinische Radiologie; Hautmann, H.; Huber, R.M. [Klinikum Innenstadt der Ludwig-Maximilians-Universitaet Muenchen (Germany). Abteilung Pulmonologie, Medizinische Klinik

    2002-08-01

    Study objectives: Assessment of the therapeutic potential of tracheobronchial stenting for obstructive tracheobronchial disease, in-vivo comparison of different stent types and development of helpful criteria for choosing the suitable stent type. Material and Methods: Prospective case analysis. Between 1993 and 1999 53 stents were implanted into the tracheobronchial system of 39 consecutive patients with benign or malignant airway obstruction. Every single stent (26 Strecker Stents, 18 Wallstents, 6 Accuflex Nitinolstents, 1 Dumon-, 1 Ruesch- and 1 Palmazstent) was recorded in an unified database. Analysis comprised clinical effectiveness, lung function if possible, relevant complications and radiologic follow-up parameters. The probability of their remaining within the tracheobronchial system, of their remaining undislocated and uncompressed was calculated using Kaplan-Meier analysis for three stent types. Results: Stent placement proved itself to be an effective treatment in 86% of the patients. Resistance could be normalized in 9/9 patients. Kaplan-Meier analysis clearly revealed a higher probability for the Wall- and Nitinolstent to remain within the tracheobronchial system and to remain uncompressed. Dislocation also occurred more rarely. Explanation of the Wallstent, however, if desired, was much more difficult compared to the Strecker stent. The Wallstent also occasionally led to the formation of granulation tissue especially at the proximal stent end and, as such, required reintervention. (orig.) [German] Ziel: Erfassung des therapeutischen Potenzials der Stentbehandlung bei tracheobronchialen Stenosen, in-vivo Vergleich verschiedener Stenttypen und Erarbeitung von geeigneten Kriterien zur Stentwahl. Material und Methodik: Prospektive Fallanalyse. Zwischen 1993 und 1999 wurden insgesamt 53 Stents in das Tracheobronichalsystem von 39 konsekutiven Patienten implantiert. Jeder einzelne Stent (26 Streckerstents, 18 Wallstents, 6 Nitinolstents, ein Dumonstent

  15. Next generation multi-particle event generators for the MSSM

    International Nuclear Information System (INIS)

    Reuter, J.; Kilian, W.; Hagiwara, K.; Krauss, F.; Schumann, S.; Rainwater, D.

    2005-12-01

    We present a next generation of multi-particle Monte Carlo (MC) Event generators for LHC and ILC for the MSSM, namely the three program packages Madgraph/MadEvent, WHiZard/O'Mega and Sherpa/Amegic++. The interesting but difficult phenomenology of supersymmetric models at the upcoming colliders demands a corresponding complexity and maturity from simulation tools. This includes multi-particle final states, reducible and irreducible backgrounds, spin correlations, real emission of photons and gluons, etc., which are incorporated in the programs presented here. The framework of a model with such a huge particle content and as complicated as the MSSM makes strenuous tests and comparison of codes inevitable. Various tests show agreement among the three different programs; the tables of cross sections produced in these tests may serve as a future reference for other codes. Furthermore, first MSSM physics analyses performed with these programs are presented here. (orig.)

  16. Generating multi-double-scroll attractors via nonautonomous approach.

    Science.gov (United States)

    Hong, Qinghui; Xie, Qingguo; Shen, Yi; Wang, Xiaoping

    2016-08-01

    It is a common phenomenon that multi-scroll attractors are realized by introducing the various nonlinear functions with multiple breakpoints in double scroll chaotic systems. Differently, we present a nonautonomous approach for generating multi-double-scroll attractors (MDSA) without changing the original nonlinear functions. By using the multi-level-logic pulse excitation technique in double scroll chaotic systems, MDSA can be generated. A Chua's circuit, a Jerk circuit, and a modified Lorenz system are given as designed example and the Matlab simulation results are presented. Furthermore, the corresponding realization circuits are designed. The Pspice results are in agreement with numerical simulation results, which verify the availability and feasibility of this method.

  17. Tracheobronchial air-liquid interface cell culture: a model for innate mucosal defense of the upper airways?

    Science.gov (United States)

    Kesimer, Mehmet; Kirkham, Sara; Pickles, Raymond J.; Henderson, Ashley G.; Alexis, Neil E.; DeMaria, Genevieve; Knight, David; Thornton, David J.; Sheehan, John K.

    2009-01-01

    Human tracheobronchial epithelial cells grown in air-liquid interface culture have emerged as a powerful tool for the study of airway biology. In this study, we have investigated whether this culture system produces “mucus” with a protein composition similar to that of in vivo, induced airway secretions. Previous compositional studies of mucous secretions have greatly underrepresented the contribution of mucins, which are major structural components of normal mucus. To overcome this limitation, we have used a mass spectrometry-based approach centered on prior separation of the mucins from the majority of the other proteins. Using this approach, we have compared the protein composition of apical secretions (AS) from well-differentiated primary human tracheobronchial cells grown at air-liquid interface and human tracheobronchial normal induced sputum (IS). A total of 186 proteins were identified, 134 from AS and 136 from IS; 84 proteins were common to both secretions, with host defense proteins being predominant. The epithelial mucins MUC1, MUC4, and MUC16 and the gel-forming mucins MUC5B and MUC5AC were identified in both secretions. Refractometry showed that the gel-forming mucins were the major contributors by mass to both secretions. When the composition of the IS was corrected for proteins that were most likely derived from saliva, serum, and migratory cells, there was considerable similarity between the two secretions, in particular, in the category of host defense proteins, which includes the mucins. This shows that the primary cell culture system is an important model for study of aspects of innate defense of the upper airways related specifically to mucus consisting solely of airway cell products. PMID:18931053

  18. Solitary Tracheobronchial Papilloma: Cytomorphology and ancillary studies with histologic correlation

    Directory of Open Access Journals (Sweden)

    Tee U Lang

    2011-01-01

    Full Text Available Solitary tracheobronchial papilloma (STBP is a rare benign tumor that primarily involves the tracheobronchial tree. Human papilloma virus (HPV infection is associated with dysplasia and a high risk of carcinoma in these lesions. The cytomorphology of STBP is not well established in the literature. Our aim is to characterize the cytomorphologic features of STBP, with histologic correlation in a series of 6 patients - 4 males and 2 females - with a mean age of 67 years (range, 53-88 years. There were 5 biopsy-proven squamous papillomas and 1 glandular papilloma. On surgical biopsy, squamous papillomas exhibited cytological atypia (4 graded mild and 1 graded moderate with focal severe dysplasia, surface erosion, and inflammation. Cytology specimens available for review included a combination of 4 fine-needle aspirations (FNAs, 2 bronchoalveolar lavages and 2 (of 3 bronchial brushings. Cytologic findings associated with squamous papillomas included atypical squamous cells and rare squamous cell resembling koilocyte in 1 bronchial brushing. Sheets of squamous cells were identified in another specimen. Several cases had a prominent background of acute inflammation, and candida was present in 1 specimen. HPV in-situ hybridization was positive in 1 case and negative in 2 cases. A p16 immunocytochemical stain performed on 1 cell block was negative. In conclusion, although STBP is a rare neoplasm, these cases may be encountered in respiratory cytology samples. FNA of papillomas yields fewer lesional cells compared to exfoliative samples. These lesions may be mistaken in cytology specimens for squamous cell carcinoma, squamous-lined cavitary lesions, an infectious (fungal process, reactive squamous metaplasia, or oral contamination.

  19. Proteolytic fragmentation and peptide mapping of human carboxyamidomethylated tracheobronchial mucin

    International Nuclear Information System (INIS)

    Rose, M.C.; Kaufman, B.; Martin, B.M.

    1989-01-01

    Human tracheobronchial mucin was isolated from lung mucosal gel by chromatography on Sepharose 4B in the presence of dissociating and reducing agents, and its thiol residues were carboxyamidomethylated with iodo[1(-14)C]acetamide. The 14C-carboxyamido-methylated mucin was purified by chromatography on Sepharose 2B. No low molecular weight components were detected by molecular sieve chromatography or polyacrylamide gel electrophoresis in the presence of dissociating and reducing agents or by analytical density centrifugation in CsCl/guanidinium chloride. After digestion of the purified 14C-mucin with trypsin-L-1-tosylamido-2-phenylethyl chloromethyl ketone, three fractions (TR-1, TR-2, and TR-3) were observed by chromatography on Sepharose 4B. TR-1, a 260-kDa mucin glycopeptide fragment, contained all of the neutral hexose and blood group activity and 20% of the radioactivity in the undigested mucin. TR-1 was refractory to a second incubation with trypsin but could be digested by papain or Pronase to a smaller mucin glycopeptide fraction, as judged by the slight decrease in apparent molecular weight on Sepharose CL-4B. These mucin glycopeptides contained approximately 50% of the radioactivity in the TR-1 fraction, indicating that the glycosylated domains of carboxyamidomethylated tracheobronchial mucin contained thiol residues. The remainder of the radioactivity from papain or Pronase digests of TR-1 eluted, like the TR-3 fractions, in the salt fraction on Sepharose CL-4B. Peptide mapping of the nonglycosylated TR-3 fraction by TLC and high voltage electrophoresis yielded six principal and several less intensely stained ninhydrin reactive components, with the radiolabel concentrated in one of the latter peptides

  20. The electrosurgical knife in an optimized intermittent cutting mode for the endoscopic treatment of benign web-like tracheobronchial stenosis.

    Science.gov (United States)

    Amat, Beatriz; Esselmann, Albert; Reichle, Guenther; Rohde, Hans-Juergen; Westhoff, Michael; Freitag, Lutz

    2012-01-01

    The established endoscopic treatment of web-like tracheobronchial stenosis is laser vaporization, but the appearance on the market of a new cutting mode with a lower coagulation effect has been proposed as an alternative to laser due to less injury to the tissue. To study the clinical and functional consequences, as well as the side effects of this technique. Afterwards, we investigated whether the use of an electrosurgical knife with this technique is as effective and convenient as an ND-YAG-laser. Between March 2005 and July 2007, included for study were 22 patients who had undergone 34 interventional bronchoscopy procedures with the VIO-300-D radiofrequency system, using a mode of the Endo-cut I program in conjunction with the reusable knife electrode. All of the patients treated (100%) presented improvements in their symptoms, in the tracheobronchial lumen diameter and in lung function, which were statistically significant. Symptom-free time was 157 ± 93 days. There was an overall decrease observed in mean obstruction (Pbenign web-like tracheobronchial stenosis as all the patients showed clinical and functional improvement, and less than 50% required a second intervention. In comparison with laser therapy, an advantage of this technique is that less fibrin is produced, probably due to the reduced anti-coagulation effect. Copyright © 2011 SEPAR. Published by Elsevier Espana. All rights reserved.

  1. Generating multi-double-scroll attractors via nonautonomous approach

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Qinghui; Xie, Qingguo, E-mail: qgxie@mail.hust.edu.cn [Wuhan National Laboratory for Optoelectronics, Wuhan 430074 (China); Shen, Yi; Wang, Xiaoping [School of Automation, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2016-08-15

    It is a common phenomenon that multi-scroll attractors are realized by introducing the various nonlinear functions with multiple breakpoints in double scroll chaotic systems. Differently, we present a nonautonomous approach for generating multi-double-scroll attractors (MDSA) without changing the original nonlinear functions. By using the multi-level-logic pulse excitation technique in double scroll chaotic systems, MDSA can be generated. A Chua's circuit, a Jerk circuit, and a modified Lorenz system are given as designed example and the Matlab simulation results are presented. Furthermore, the corresponding realization circuits are designed. The Pspice results are in agreement with numerical simulation results, which verify the availability and feasibility of this method.

  2. Expandable metallic stents in the palliative treatment of malignant tracheobronchial stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Woong; Jung, Gyoo Sik; Kim, Seong Min; Lee, Seung Ryong; Kim, Hyun Sook; Huh, Jin Do; Joh, Young Duk [Kosin Medical College, Pusan (Korea, Republic of)

    1998-05-01

    The purpose of this study is to report the outcome of using expandable metallic stent in the management of malignant tracheobronchial stenosis with dyspnea. Under fluoroscopic and bronchoscopic guidance, seven patients with malignant airway stenosis were treated with ten expandable metallic stents. The cause of stenosis was metastasis from esophageal cancer in five patients, recurrent adenoid cystic carcinoma of the trachea in one, and primary lung cancer in one. The major sites of obstruction were the trachea in four patients, the left main bronchus in one, the trachea and left main bronchus in one, and the trachea and both bronchi in one. Chest radiography (n=7), bronchoscopy (n=5), pulmonary function test (PFT)(n=3), and spirometry(n=1) were performed before and after stent placement. In all seven patients, the stent was successfully placed at the lesion sites and dyspnea began to improve immediately. After the procedure, chest radiography and bronchoscopy showed an increase in airway diameter. After the procedure, chest radiography and bronchoscopy showed an increase in airway diameter. After stent placement, forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) improved 53% and 56%, respectively. Peak flow velocity also changed from 46 L/min to 200 L/min. During median follow-up of 67 (41-1565) days, one stent migration occurred. In one patient, proximal tumor overgrowth occurred, and in one, tumor ingrowth was treated with balloon dilatation. For in the palliative treatment of malignant tracheobronchial stenosis with dyspnea, placement of expandable metal stents is safe and effective. (author). 21 refs., 1 tabs., 3 figs.

  3. Expandable metallic stents in the palliative treatment of malignant tracheobronchial stenosis

    International Nuclear Information System (INIS)

    Park, Jong Woong; Jung, Gyoo Sik; Kim, Seong Min; Lee, Seung Ryong; Kim, Hyun Sook; Huh, Jin Do; Joh, Young Duk

    1998-01-01

    The purpose of this study is to report the outcome of using expandable metallic stent in the management of malignant tracheobronchial stenosis with dyspnea. Under fluoroscopic and bronchoscopic guidance, seven patients with malignant airway stenosis were treated with ten expandable metallic stents. The cause of stenosis was metastasis from esophageal cancer in five patients, recurrent adenoid cystic carcinoma of the trachea in one, and primary lung cancer in one. The major sites of obstruction were the trachea in four patients, the left main bronchus in one, the trachea and left main bronchus in one, and the trachea and both bronchi in one. Chest radiography (n=7), bronchoscopy (n=5), pulmonary function test (PFT)(n=3), and spirometry(n=1) were performed before and after stent placement. In all seven patients, the stent was successfully placed at the lesion sites and dyspnea began to improve immediately. After the procedure, chest radiography and bronchoscopy showed an increase in airway diameter. After the procedure, chest radiography and bronchoscopy showed an increase in airway diameter. After stent placement, forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) improved 53% and 56%, respectively. Peak flow velocity also changed from 46 L/min to 200 L/min. During median follow-up of 67 (41-1565) days, one stent migration occurred. In one patient, proximal tumor overgrowth occurred, and in one, tumor ingrowth was treated with balloon dilatation. For in the palliative treatment of malignant tracheobronchial stenosis with dyspnea, placement of expandable metal stents is safe and effective. (author). 21 refs., 1 tabs., 3 figs

  4. Multi-Group Covariance Data Generation from Continuous-Energy Monte Carlo Transport Calculations

    International Nuclear Information System (INIS)

    Lee, Dong Hyuk; Shim, Hyung Jin

    2015-01-01

    The sensitivity and uncertainty (S/U) methodology in deterministic tools has been utilized for quantifying uncertainties of nuclear design parameters induced by those of nuclear data. The S/U analyses which are based on multi-group cross sections can be conducted by an simple error propagation formula with the sensitivities of nuclear design parameters to multi-group cross sections and the covariance of multi-group cross section. The multi-group covariance data required for S/U analysis have been produced by nuclear data processing codes such as ERRORJ or PUFF from the covariance data in evaluated nuclear data files. However in the existing nuclear data processing codes, an asymptotic neutron flux energy spectrum, not the exact one, has been applied to the multi-group covariance generation since the flux spectrum is unknown before the neutron transport calculation. It can cause an inconsistency between the sensitivity profiles and the covariance data of multi-group cross section especially in resolved resonance energy region, because the sensitivities we usually use are resonance self-shielded while the multi-group cross sections produced from an asymptotic flux spectrum are infinitely-diluted. In order to calculate the multi-group covariance estimation in the ongoing MC simulation, mathematical derivations for converting the double integration equation into a single one by utilizing sampling method have been introduced along with the procedure of multi-group covariance tally

  5. Being part of a multi-generational medical practice team.

    Science.gov (United States)

    Hills, Laura

    2010-01-01

    What happens when you find yourself working in your medical practice every day with co-workers who are the ages of your parents or children? Do you find yourself reverting to age-related roles? Do you become exasperated with or bewildered by the values and behaviors of older or younger colleagues? This article explores the challenges and opportunities the medical practice staff member faces when he or she is part of a multi-generational medical practice team. It describes the tensions that often occur when a medical practice staff runs the gamut from those who remember using a library card catalog and those who can't remember the days before Google. It describes the core values, career goals, key formative events, and attitudes that may have shaped the thinking and behavior of the four generations that may work in the medical practice today: Traditionalists, Baby Boomers, Generation X, and Generation Y. It suggests preferred communication and learning methods for staff members of different generations. Finally, this article offers 10 best practices for working in a multi-generational staff and for creating a supportive multi-generational medical practice culture.

  6. Effect of proton-conduction in electrolyte on electric efficiency of multi-stage solid oxide fuel cells

    Science.gov (United States)

    Matsuzaki, Yoshio; Tachikawa, Yuya; Somekawa, Takaaki; Hatae, Toru; Matsumoto, Hiroshige; Taniguchi, Shunsuke; Sasaki, Kazunari

    2015-07-01

    Solid oxide fuel cells (SOFCs) are promising electrochemical devices that enable the highest fuel-to-electricity conversion efficiencies under high operating temperatures. The concept of multi-stage electrochemical oxidation using SOFCs has been proposed and studied over the past several decades for further improving the electrical efficiency. However, the improvement is limited by fuel dilution downstream of the fuel flow. Therefore, evolved technologies are required to achieve considerably higher electrical efficiencies. Here we present an innovative concept for a critically-high fuel-to-electricity conversion efficiency of up to 85% based on the lower heating value (LHV), in which a high-temperature multi-stage electrochemical oxidation is combined with a proton-conducting solid electrolyte. Switching a solid electrolyte material from a conventional oxide-ion conducting material to a proton-conducting material under the high-temperature multi-stage electrochemical oxidation mechanism has proven to be highly advantageous for the electrical efficiency. The DC efficiency of 85% (LHV) corresponds to a net AC efficiency of approximately 76% (LHV), where the net AC efficiency refers to the transmission-end AC efficiency. This evolved concept will yield a considerably higher efficiency with a much smaller generation capacity than the state-of-the-art several tens-of-MW-class most advanced combined cycle (MACC).

  7. Mathematical model of snake-type multi-directional wave generation

    Science.gov (United States)

    Muarif; Halfiani, Vera; Rusdiana, Siti; Munzir, Said; Ramli, Marwan

    2018-01-01

    Research on extreme wave generation is one intensive research on water wave study because the fact that the occurrence of this wave in the ocean can cause serious damage to the ships and offshore structures. One method to be used to generate the wave is self-correcting. This method controls the signal on the wavemakers in a wave tank. Some studies also consider the nonlinear wave generation in a wave tank by using numerical approach. Study on wave generation is essential in the effectiveness and efficiency of offshore structure model testing before it can be operated in the ocean. Generally, there are two types of wavemakers implemented in the hydrodynamic laboratory, piston-type and flap-type. The flap-type is preferred to conduct a testing to a ship in deep water. Single flap wavemaker has been explained in many studies yet snake-type wavemaker (has more than one flap) is still a case needed to be examined. Hence, the formulation in controlling the wavemaker need to be precisely analyzed such that the given input can generate the desired wave in the space-limited wave tank. By applying the same analogy and methodhology as the previous study, this article represents multi-directional wave generation by implementing snake-type wavemakers.

  8. Management of Laryngotracheal and Tracheobronchial Injuries

    Directory of Open Access Journals (Sweden)

    Hamid Reza Davari

    2010-09-01

    Full Text Available Laryngotracheal and tracheobronchial injuries are uncommon,and their successful diagnosis and management often require ahigh level of expertise. This paper aimed at retrospectiveanalysis of a thoracic surgeon's experience in the diagnosisand management of traumatic injuries to the larynx, tracheaand major bronchi. Forty one patients with major airwaytrauma were managed from March 1994 to November 2008.Their demographic characteristics including age, gender,mechanisms and locations of injuries, associated other organinjuries as well as surgical airway managements and the outcomeswere recorded. Seven patients had re-implantation ofthe main bronchus, and one patient had a repair of the rightupper lobe bronchus with concomitant bilobectomy. In casesof tracheal injury, 16 patients had a primary repair of trachea.However, seven patients with tracheal injury first conservativeapproaches, but 4 of them were later subjected to sleeve resectionof trachea. In patients with laryngotracheal injuries, and ina patient with thermal injury, Montgomery T-Tube was usedwith or without repair and/or reconstruction. Four patients died,but no significant morbidity was seen in others. The analysis ofthe cases suggests that laryngotracheal and tracheobronchialinjuries require early correct diagnosis, skillful management,and prompt individualized surgical airway repair.

  9. Improving Video Generation for Multi-functional Applications

    OpenAIRE

    Kratzwald, Bernhard; Huang, Zhiwu; Paudel, Danda Pani; Dinesh, Acharya; Van Gool, Luc

    2017-01-01

    In this paper, we aim to improve the state-of-the-art video generative adversarial networks (GANs) with a view towards multi-functional applications. Our improved video GAN model does not separate foreground from background nor dynamic from static patterns, but learns to generate the entire video clip conjointly. Our model can thus be trained to generate - and learn from - a broad set of videos with no restriction. This is achieved by designing a robust one-stream video generation architectur...

  10. Multi-generational effects of propranolol on Daphnia magna at different environmental concentrations

    International Nuclear Information System (INIS)

    Jeong, Tae-Yong; Kim, Hyun Young; Kim, Sang Don

    2015-01-01

    To evaluate the effects of propranolol on Daphnia magna (D. magna), we employed a multi-generational exposure period for eight generations and an environmentally relevant low concentration with 1.5 ng/L, 0.2 μg/L and 26 μg/L to reflect a realistic exposure scenario. Physiological endpoints were checked, including growth, number of neonates, heart rate, frequency of abdominal appendage movement and malformation rate of neonates. In the results, growth and abdominal appendage movement were affected by environmental concentration during several generations, and the responses showed consistent tendencies of response increase with concentration increase. Heart rate was the only endpoint affected throughout all exposure generations. Inhibitory and acceleratory effects on heart rate, growth and abdominal appendage movement suggest that it is necessary to cover sub-lethal endpoints of non-targeted organisms in eco-toxicity study because the physiological responses were detected at much lower concentrations than the results of traditional toxicity tests, including environmental concentration. - Highlights: • Multi-generational exposure was conducted to evaluate the effect of propranolol on Daphnia magna. • Heart rate was the only endpoint affected throughout all exposure generations. • Growth and abdominal appendage movement were affected at environmental concentrations. • Time series fluctuations in responses appeared with no tendencies throughout all generations. • It is necessary to cover sub-organismal endpoints and long-term exposure in ecotoxicity test. - Heart rate, growth and abdominal appendage movement of D. magna were affected by the multigenerational exposure of propranolol at environmental levels.

  11. Design and optimization of flexible multi-generation systems

    DEFF Research Database (Denmark)

    Lythcke-Jørgensen, Christoffer Ernst

    variations and dynamics, and energy system analysis, which fails to consider process integration synergies in local systems. The primary objective of the thesis is to derive a methodology for linking process design practices with energy system analysis for enabling coherent and holistic design optimization...... of flexible multi-generation system. In addition, the case study results emphasize the importance of considering flexible operation, systematic process integration, and systematic assessment of uncertainties in the design optimization. It is recommended that future research focus on assessing system impacts...... from flexible multi-generation systems and performance improvements from storage options....

  12. In-vivo counting of 241Am in human lungs and tracheobronchial lymph nodes

    International Nuclear Information System (INIS)

    Northcutt, A.R.; Binney, S.E.; Palmer, H.E.

    1988-01-01

    A study was conducted of a human male who had inhaled a mixture of 241 Am and Pu. To distinguish 241 Am deposited in the subject's lungs from translocated activity deposited in the tracheobronchial lymph nodes (TBLN), two intrinsic Ge detectors were collimated with 0.3-cm Pb sheeting. A tissue-equivalent phantom containing either 22.9 kBq (620 nCi) of 241 Am in the lungs or a 81.4 kBq (2200 nCi) 241 Am point source in the TBLN was measured. Calibration curves observed from lateral differential scans on the phantom were compared to data obtained by the same detection system for a human male with a measured lung deposition of 89 Bq (2.4 nCi) of 241 Am. Comparison of the human data to the calibration curves indicated the activity was restricted primarily to the lungs. The calibration curves demonstrate that this method is useful in determining the distribution of inhaled radioactivity between the lungs and TBLN. The measured activity from the male subject generally supported the ICRP Publication 30 model translocation prediction for class Y compounds

  13. Boundary element numerical method for the electric field generated by oblique multi-needle electrodes

    Institute of Scientific and Technical Information of China (English)

    LIU FuPing; WANG AnLing; WANG AnXuan; CAO YueZu; CHEN Qiang; YANG ChangChun

    2009-01-01

    According to the electric potential of oblique multi-needle electrodes (OMNE) in biological tissue, the discrete equations based on the indetermination linear current density were established by the boundary element integral equations (BEIE). The non-uniform distribution of the current flowing from multi-needle electrodes to conductive biological tissues was imaged by solving a set of linear equa-tions. Then, the electric field and potential generated by OMNE in biological tissues at any point may be determined through the boundary element method (BEM). The time of program running and stability of computing method are examined by an example. It demonstrates that the algorithm possesses a quick speed and the steady computed results. It means that this method has an important referenced significance for computing the field and the potential generated by OMNE in bio-tissue, which is a fast, effective and accurate computing method.

  14. Fabrication of ATO/Graphene Multi-layered Transparent Conducting Thin Films

    Science.gov (United States)

    Li, Na; Chen, Fei; Shen, Qiang; Wang, Chuanbin; Zhang, Lianmeng

    2013-03-01

    A novel transparent conducting oxide based on the ATO/graphene multi-layered thin films has been developed to satisfy the application of transparent conductive electrode in solar cells. The ATO thin films are prepared by pulsed laser deposition method with high quality, namely the sheet resistance of 49.5 Ω/sq and average transmittance of 81.9 %. The prepared graphene sheet is well reduced and shows atomically thin, spotty distributed appearance on the top of the ATO thin films. The XRD and optical micrographs are used to confirm the successfully preparation of the ATO/graphene multi-layered thin films. The Hall measurements and UV-Vis spectrophotometer are conducted to evaluate the sheet resistance and optical transmittance of the innovative structure. It is found that graphene can improve the electrical properties of the ATO thin films with little influence on the optical transmittance.

  15. Fabrication of ATO/Graphene Multi-layered Transparent Conducting Thin Films

    International Nuclear Information System (INIS)

    Li Na; Chen Fei; Shen Qiang; Wang Chuanbin; Zhang Lianmeng

    2013-01-01

    A novel transparent conducting oxide based on the ATO/graphene multi-layered thin films has been developed to satisfy the application of transparent conductive electrode in solar cells. The ATO thin films are prepared by pulsed laser deposition method with high quality, namely the sheet resistance of 49.5 Ω/sq and average transmittance of 81.9 %. The prepared graphene sheet is well reduced and shows atomically thin, spotty distributed appearance on the top of the ATO thin films. The XRD and optical micrographs are used to confirm the successfully preparation of the ATO/graphene multi-layered thin films. The Hall measurements and UV-Vis spectrophotometer are conducted to evaluate the sheet resistance and optical transmittance of the innovative structure. It is found that graphene can improve the electrical properties of the ATO thin films with little influence on the optical transmittance.

  16. Cultural Transmission and Evolution of Melodic Structures in Multi-generational Signaling Games

    DEFF Research Database (Denmark)

    Lumaca, Massimo; Baggio, G.

    2017-01-01

    , and basic and compound emotions as meanings, were transmitted from senders to receivers along diffusion chains in which the receiver in each game became the sender in the next game. During transmission, structural regularities accumulated in the signaling systems, following principles of proximity, symmetry...... and cognitive constraints similarly affect the evolution of musical systems? We conducted an experiment on the cultural evolution of artificial melodic systems, using multi-generational signaling games as a laboratory model of cultural transmission. Signaling systems, using five-tone sequences as signals...

  17. Assessment of litter prevalence of Mycoplasma hyopneumoniae in preweaned piglets utilizing an antemortem tracheobronchial mucus collection technique and a real-time polymerase chain reaction assay.

    Science.gov (United States)

    Vangroenweghe, Frédéric; Karriker, Locke; Main, Rodger; Christianson, Eric; Marsteller, Thomas; Hammen, Kristin; Bates, Jessica; Thomas, Paul; Ellingson, Josh; Harmon, Karen; Abate, Sarah; Crawford, Kimberly

    2015-09-01

    The swine industry currently lacks validated antemortem methods of detecting baseline herd prevalence of Mycoplasma hyopneumoniae. The focus of our study was to evaluate alternative antemortem detection techniques and to determine baseline litter prevalence in preweaned pig populations utilizing the selected technique and a real-time polymerase chain reaction (qPCR) assay. Preliminary data was analyzed on weaned piglets with evidence of respiratory disease (n = 32). Five sample types (antemortem nasal swab, tracheobronchial mucus, postmortem deep airway swab, bronchoalveolar lavage, and lung tissue) were collected from each pig. Individual samples were tested for M. hyopneumoniae using qPCR. Compared to nasal swabs, tracheobronchial mucus demonstrated higher test sensitivity (P hyopneumoniae. Two out of 180 litters revealed a positive result (1.1%). Individual qPCR assays were run on the samples collected from sow farm 4. Five out of 30 samples revealed a positive result (16.7%). Tracheobronchial mucus collection in combination with qPCR is a sensitive antemortem sampling technique that can be used to estimate the prevalence of M. hyopneumoniae in preweaned pigs, thus providing insight into the infection dynamics across the entire farrow-to-finish process. © 2015 The Author(s).

  18. Multi-region fuzzy logic controller with local PID controllers for U-tube steam generator in nuclear power plant

    Directory of Open Access Journals (Sweden)

    Puchalski Bartosz

    2015-12-01

    Full Text Available In the paper, analysis of multi-region fuzzy logic controller with local PID controllers for steam generator of pressurized water reactor (PWR working in wide range of thermal power changes is presented. The U-tube steam generator has a nonlinear dynamics depending on thermal power transferred from coolant of the primary loop of the PWR plant. Control of water level in the steam generator conducted by a traditional PID controller which is designed for nominal power level of the nuclear reactor operates insufficiently well in wide range of operational conditions, especially at the low thermal power level. Thus the steam generator is often controlled manually by operators. Incorrect water level in the steam generator may lead to accidental shutdown of the nuclear reactor and consequently financial losses. In the paper a comparison of proposed multi region fuzzy logic controller and traditional PID controllers designed only for nominal condition is presented. The gains of the local PID controllers have been derived by solving appropriate optimization tasks with the cost function in a form of integrated squared error (ISE criterion. In both cases, a model of steam generator which is readily available in literature was used for control algorithms synthesis purposes. The proposed multi-region fuzzy logic controller and traditional PID controller were subjected to broad-based simulation tests in rapid prototyping software - Matlab/Simulink. These tests proved the advantage of multi-region fuzzy logic controller with local PID controllers over its traditional counterpart.

  19. Airflow in Tracheobronchial Tree of Subjects with Tracheal Bronchus Simulated Using CT Image Based Models and CFD Method.

    Science.gov (United States)

    Qi, Shouliang; Zhang, Baihua; Yue, Yong; Shen, Jing; Teng, Yueyang; Qian, Wei; Wu, Jianlin

    2018-03-01

    Tracheal Bronchus (TB) is a rare congenital anomaly characterized by the presence of an abnormal bronchus originating from the trachea or main bronchi and directed toward the upper lobe. The airflow pattern in tracheobronchial trees of TB subjects is critical, but has not been systemically studied. This study proposes to simulate the airflow using CT image based models and the computational fluid dynamics (CFD) method. Six TB subjects and three health controls (HC) are included. After the geometric model of tracheobronchial tree is extracted from CT images, the spatial distribution of velocity, wall pressure, wall shear stress (WSS) is obtained through CFD simulation, and the lobar distribution of air, flow pattern and global pressure drop are investigated. Compared with HC subjects, the main bronchus angle of TB subjects and the variation of volume are large, while the cross-sectional growth rate is small. High airflow velocity, wall pressure, and WSS are observed locally at the tracheal bronchus, but the global patterns of these measures are still similar to those of HC. The ratio of airflow into the tracheal bronchus accounts for 6.6-15.6% of the inhaled airflow, decreasing the ratio to the right upper lobe from 15.7-21.4% (HC) to 4.9-13.6%. The air into tracheal bronchus originates from the right dorsal near-wall region of the trachea. Tracheal bronchus does not change the global pressure drop which is dependent on multiple variables. Though the tracheobronchial trees of TB subjects present individualized features, several commonalities on the structural and airflow characteristics can be revealed. The observed local alternations might provide new insight into the reason of recurrent local infections, cough and acute respiratory distress related to TB.

  20. Multi-objective and multi-criteria optimization for power generation expansion planning with CO2 mitigation in Thailand

    Directory of Open Access Journals (Sweden)

    Kamphol Promjiraprawat

    2013-06-01

    Full Text Available In power generation expansion planning, electric utilities have encountered the major challenge of environmental awareness whilst being concerned with budgetary burdens. The approach for selecting generating technologies should depend on economic and environmental constraint as well as externalities. Thus, the multi-objective optimization becomes a more attractive approach. This paper presents a hybrid framework of multi-objective optimization and multi-criteria decision making to solve power generation expansion planning problems in Thailand. In this paper, CO2 emissions and external cost are modeled as a multi-objective optimization problem. Then the analytic hierarchy process is utilized to determine thecompromised solution. For carbon capture and storage technology, CO2 emissions can be mitigated by 74.7% from the least cost plan and leads to the reduction of the external cost of around 500 billion US dollars over the planning horizon. Results indicate that the proposed approach provides optimum cost-related CO2 mitigation plan as well as external cost.

  1. Multiple optical code-label processing using multi-wavelength frequency comb generator and multi-port optical spectrum synthesizer.

    Science.gov (United States)

    Moritsuka, Fumi; Wada, Naoya; Sakamoto, Takahide; Kawanishi, Tetsuya; Komai, Yuki; Anzai, Shimako; Izutsu, Masayuki; Kodate, Kashiko

    2007-06-11

    In optical packet switching (OPS) and optical code division multiple access (OCDMA) systems, label generation and processing are key technologies. Recently, several label processors have been proposed and demonstrated. However, in order to recognize N different labels, N separate devices are required. Here, we propose and experimentally demonstrate a large-scale, multiple optical code (OC)-label generation and processing technology based on multi-port, a fully tunable optical spectrum synthesizer (OSS) and a multi-wavelength electro-optic frequency comb generator. The OSS can generate 80 different OC-labels simultaneously and can perform 80-parallel matched filtering. We also demonstrated its application to OCDMA.

  2. Treatment of multiple-level tracheobronchial stenosis secondary to endobronchial tuberculosis using bronchoscopic balloon dilatation with topical mitomycin-C.

    Science.gov (United States)

    Faisal, Mohamed; Harun, Hafaruzi; Hassan, Tidi M; Ban, Andrea Y L; Chotirmall, Sanjay H; Abdul Rahaman, Jamalul Azizi

    2016-04-14

    Tracheobronchial stenosis is a known complication of endobronchial tuberculosis. Despite antituberculous and steroid therapy, the development of bronchial stenosis is usually irreversible and requires airway patency to be restored by either bronchoscopic or surgical interventions. We report the use of balloon dilatation and topical mitomycin-C to successful restore airway patency. We present a 24-year old lady with previous pulmonary tuberculosis and laryngeal tuberculosis in 2007 and 2013 respectively who presented with worsening dyspnoea and stridor. She had total left lung collapse with stenosis of both the upper trachea and left main bronchus. She underwent successful bronchoscopic balloon and manual rigid tube dilatation with topical mitomycin-C application over the stenotic tracheal segment. A second bronchoscopic intervention was performed after 20 weeks for the left main bronchus stenosis with serial balloon dilatation and topical mitomycin-C application. These interventions led to significant clinical and radiographic improvements. This case highlights that balloon dilatation and topical mitomycin-C application should be considered in selected patients with tracheobronchial stenosis following endobronchial tuberculosis, avoiding airway stenting and invasive surgical intervention.

  3. Evaluating the interaction of a tracheobronchial stent in an ovine in-vivo model.

    Science.gov (United States)

    McGrath, Donnacha J; Thiebes, Anja Lena; Cornelissen, Christian G; O'Brien, Barry; Jockenhoevel, Stefan; Bruzzi, Mark; McHugh, Peter E

    2018-04-01

    Tracheobronchial stents are used to restore patency to stenosed airways. However, these devices are associated with many complications such as stent migration, granulation tissue formation, mucous plugging and stent strut fracture. Of these, granulation tissue formation is the complication that most frequently requires costly secondary interventions. In this study a biomechanical lung modelling framework recently developed by the authors to capture the lung in-vivo stress state under physiological loading is employed in conjunction with ovine pre-clinical stenting results and device experimental data to evaluate the effect of stent interaction on granulation tissue formation. Stenting is simulated using a validated model of a prototype covered laser-cut tracheobronchial stent in a semi-specific biomechanical lung model, and physiological loading is performed. Two computational methods are then used to predict possible granulation tissue formation: the standard method which utilises the increase in maximum principal stress change, and a newly proposed method which compares the change in contact pressure over a respiratory cycle. These computational predictions of granulation tissue formation are then compared to pre-clinical stenting observations after a 6-week implantation period. Experimental results of the pre-clinical stent implantation showed signs of granulation tissue formation both proximally and distally, with a greater proximal reaction. The standard method failed to show a correlation with the experimental results. However, the contact change method showed an apparent correlation with granulation tissue formation. These results suggest that this new method could be used as a tool to improve future device designs.

  4. Multi-Stable Conductance States in Metallic Double-Walled Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Ci Lijie

    2009-01-01

    Full Text Available Abstract Electrical transport properties of individual metallic double-walled carbon nanotubes (DWCNTs were measured down to liquid helium temperature, and multi-stable conductance states were found in DWCNTs. At a certain temperature, DWCNTs can switch continuously between two or more electronic states, but below certain temperature, DWCNTs are stable only at one of them. The temperature for switching is always different from tube to tube, and even different from thermal cycle to cycle for the same tube. In addition to thermal activation, gate voltage scanning can also realize such switching among different electronic states. The multi-stable conductance states in metallic DWCNTs can be attributed to different Fermi level or occasional scattering centers induced by different configurations between their inner and outer tubes.

  5. Tracheobronchial puncture-site nodular reaction (TPNR following endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA: Systematic review of case reports

    Directory of Open Access Journals (Sweden)

    Karan Madan

    2017-01-01

    Full Text Available Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA is a minimally invasive and efficacious diagnostic modality for lung cancer staging and evaluation of undiagnosed mediastinal lymphadenopathy. Procedure-related complications are uncommon. We herein report an infrequently described phenomenon following EBUS-TBNA in which two patients developed nodular granulation tissue at the tracheobronchial puncture site. On systematic review, we found description of such phenomena by terminologies such as endobronchial inflammatory polyp, granuloma, and endobronchial mass. The endobronchial inflammatory polyp has been one of the most commonly used terminologies for these; but in most cases, the classical features of an inflammatory polyp are lacking. We propose the term, tracheobronchial puncture-site nodular reaction (TPNR with further classification into granulomatous and nongranulomatous subtypes, for standardized reporting of such reactions following transbronchial needle aspiration procedures. Knowledge of this entity and standardized nomenclature shall help in better characterization of the outcomes and risk factors for the occurrence of these reactions.

  6. Zinc-dependent multi-conductance channel activity in mitochondria isolated from ischemic brain.

    Science.gov (United States)

    Bonanni, Laura; Chachar, Mushtaque; Jover-Mengual, Teresa; Li, Hongmei; Jones, Adrienne; Yokota, Hidenori; Ofengeim, Dimitry; Flannery, Richard J; Miyawaki, Takahiro; Cho, Chang-Hoon; Polster, Brian M; Pypaert, Marc; Hardwick, J Marie; Sensi, Stefano L; Zukin, R Suzanne; Jonas, Elizabeth A

    2006-06-21

    Transient global ischemia is a neuronal insult that induces delayed cell death. A hallmark event in the early post-ischemic period is enhanced permeability of mitochondrial membranes. The precise mechanisms by which mitochondrial function is disrupted are, as yet, unclear. Here we show that global ischemia promotes alterations in mitochondrial membrane contact points, a rise in intramitochondrial Zn2+, and activation of large, multi-conductance channels in mitochondrial outer membranes by 1 h after insult. Mitochondrial channel activity was associated with enhanced protease activity and proteolytic cleavage of BCL-xL to generate its pro-death counterpart, deltaN-BCL-xL. The findings implicate deltaN-BCL-xL in large, multi-conductance channel activity. Consistent with this, large channel activity was mimicked by introduction of recombinant deltaN-BCL-xL to control mitochondria and blocked by introduction of a functional BCL-xL antibody to post-ischemic mitochondria via the patch pipette. Channel activity was also inhibited by nicotinamide adenine dinucleotide, indicative of a role for the voltage-dependent anion channel (VDAC) of the outer mitochondrial membrane. In vivo administration of the membrane-impermeant Zn2+ chelator CaEDTA before ischemia or in vitro application of the membrane-permeant Zn2+ chelator tetrakis-(2-pyridylmethyl) ethylenediamine attenuated channel activity, suggesting a requirement for Zn2+. These findings reveal a novel mechanism by which ischemic insults disrupt the functional integrity of the outer mitochondrial membrane and implicate deltaN-BCL-xL and VDAC in the large, Zn2+-dependent mitochondrial channels observed in post-ischemic hippocampal mitochondria.

  7. [Fatal toxic respiratory epitheliolysis. Subacute tracheo-bronchial desquamation in Stevens-Johnson syndrome].

    Science.gov (United States)

    Martin, L; Hazouard, E; Michalak-Provost, S; Maurage, C; Machet, L

    2001-09-01

    Acute bronchial mucosal sloughing related to Toxic Epidermal Necrolysis (Lyell syndrome) is widely reported in literature. On the contrary severe respiratory involvement is rare in post-infectious or toxic Epitheliolysis (Stevens-Johnson syndrome). There is no well-known predictive sign of bronchial epithelium involvement. An 18-year-old patient was admitted for Stevens-Johnson syndrome related to sulfasalazine (salazosulfapyridine). There were no respiratory signs. An acute respiratory failure occurred 36 hours after from admission due to an obstructive and desquamative necrosis of the tracheobronchial epithelium. We purpose that a fiberoptic laryngoscopy should be performed even in non-dyspneic patients suffering from Stevens-Johnson syndrome if hypersecretion is present. Fiberoptic bronchoscopy can be helpful in these cases.

  8. Heat conduction analysis of multi-layered FGMs considering the finite heat wave speed

    International Nuclear Information System (INIS)

    Rahideh, H.; Malekzadeh, P.; Golbahar Haghighi, M.R.

    2012-01-01

    Highlights: ► Using a layerwise-incremental differential quadrature for heat transfer of FGMs. ► Superior accuracy with fewer degrees of freedom of the method with respect to FEM. ► Considering multi-layered functionally graded materials. ► Hyperbolic heat transfer analysis of thermal system with heat generation. ► Showing the effect of heat wave speed on thermal characteristic of the system. - Abstract: In this work, the heat conduction with finite wave heat speed of multi-layered domain made of functionally graded materials (FGMs) subjected to heat generation is simulated. For this purpose, the domain is divided into a set of mathematical layers, the number of which can be equal or greater than those of the physical layers. Then, in each mathematical layer, the non-Fourier heat transfer equations are employed. Since, the governing equations have variable coefficients due to FGM properties, as an efficient and accurate method the differential quadrature method (DQM) is adopted to discretize both spatial and temporal domains in each layer. This results in superior accuracy with fewer degrees of freedom than conventional finite element method (FEM). To verify this advantages through some comparison studies, a finite element solution are also obtained. After demonstrating the convergence and accuracy of the method, the effects of heat wave speed for two different set of boundary conditions on the temperature distribution and heat flux of the domain are studied.

  9. Aquamous cell carcinomas of the lung which presented as numerous polypoid nodules in the tracheobronchial tree: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun Gyu; Choi, Yo Won; Yoon, Hyun Jung; Paik, Seung Sam [Hanyang University Hospital, Hanyang University College of Medicine, Seoul (Korea, Republic of)

    2017-03-15

    We report a case of squamous cell carcinomas of the lung, which presented as numerous polypoid nodules in the tracheobronchial tree. They occurred at two years and 7 months after resection of squamous cell carcinoma, which presented as a lung nodule in the left lower lobe, and at 7 months after resection of tracheal squamous cell carcinoma.

  10. Aquamous cell carcinomas of the lung which presented as numerous polypoid nodules in the tracheobronchial tree: A case report

    International Nuclear Information System (INIS)

    Lee, Hyun Gyu; Choi, Yo Won; Yoon, Hyun Jung; Paik, Seung Sam

    2017-01-01

    We report a case of squamous cell carcinomas of the lung, which presented as numerous polypoid nodules in the tracheobronchial tree. They occurred at two years and 7 months after resection of squamous cell carcinoma, which presented as a lung nodule in the left lower lobe, and at 7 months after resection of tracheal squamous cell carcinoma

  11. Fabrication of Multi-Harmonic Buncher for Pulsed Proton Beam Generation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, H. S.; Kwon, H. J.; Cho, Y. S. [Korea Multipurpose Accelerator Complex, Gyeongju (Korea, Republic of)

    2015-05-15

    Fast neutrons with a broad spectrum can be generated by irradiating the proton beams on target materials. To measure the neutron energy by time of flight (TOF) method, the short pulse width of the proton beam is preferred because the neutron energy uncertainty is proportional to the pulse width. In addition, the pulse repetition rate should be low enough to extend the lower limit of the available neutron energy. Pulsed proton beam generation system is designed based on an electrostatic deflector and slit system as shown in Fig. 1. In a simple deflector with slit system, most of the proton beam is blocked by slit, especially when the beam pulse width is short. The ideal field pattern inside the buncher cavity is saw-tooth wave. To make the field pattern similar to the saw-tooth waveform, we adopted a multi-harmonic buncher (MHB). The design for the multi-harmonic buncher including 3D electromagnetic calculation has been performed. Based on the design, a multi-harmonic buncher cavity was fabricated. It consists of two resonators, two drift tubes and a vacuum chamber. The resonator is a quarter-wave coaxial resonator type. The drift tube is connected to the resonator by using a coaxial vacuum feedthrough. Design summary and detailed fabrication method of the multi-harmonic buncher is presented in this paper. A multi-harmonic buncher for a proton beam chopper system to generate a short pulse neutron beam was designed, fabricated and assembled.

  12. Solution of axisymmetric transient inverse heat conduction problems using parameter estimation and multi block methods

    International Nuclear Information System (INIS)

    Azimi, A.; Hannani, S.K.; Farhanieh, B.

    2005-01-01

    In this article, a comparison between two iterative inverse techniques to solve simultaneously two unknown functions of axisymmetric transient inverse heat conduction problems in semi complex geometries is presented. The multi-block structured grid together with blocked-interface nodes is implemented for geometric decomposition of physical domain. Numerical scheme for solution of transient heat conduction equation is the finite element method with frontal technique to solve algebraic system of discrete equations. The inverse heat conduction problem involves simultaneous unknown time varying heat generation and time-space varying boundary condition estimation. Two parameter-estimation techniques are considered, Levenberg-Marquardt scheme and conjugate gradient method with adjoint problem. Numerically computed exact and noisy data are used for the measured transient temperature data needed in the inverse solution. The results of the present study for a configuration including two joined disks with different heights are compared to those of exact heat source and temperature boundary condition, and show good agreement. (author)

  13. ODG: Omics database generator - a tool for generating, querying, and analyzing multi-omics comparative databases to facilitate biological understanding.

    Science.gov (United States)

    Guhlin, Joseph; Silverstein, Kevin A T; Zhou, Peng; Tiffin, Peter; Young, Nevin D

    2017-08-10

    Rapid generation of omics data in recent years have resulted in vast amounts of disconnected datasets without systemic integration and knowledge building, while individual groups have made customized, annotated datasets available on the web with few ways to link them to in-lab datasets. With so many research groups generating their own data, the ability to relate it to the larger genomic and comparative genomic context is becoming increasingly crucial to make full use of the data. The Omics Database Generator (ODG) allows users to create customized databases that utilize published genomics data integrated with experimental data which can be queried using a flexible graph database. When provided with omics and experimental data, ODG will create a comparative, multi-dimensional graph database. ODG can import definitions and annotations from other sources such as InterProScan, the Gene Ontology, ENZYME, UniPathway, and others. This annotation data can be especially useful for studying new or understudied species for which transcripts have only been predicted, and rapidly give additional layers of annotation to predicted genes. In better studied species, ODG can perform syntenic annotation translations or rapidly identify characteristics of a set of genes or nucleotide locations, such as hits from an association study. ODG provides a web-based user-interface for configuring the data import and for querying the database. Queries can also be run from the command-line and the database can be queried directly through programming language hooks available for most languages. ODG supports most common genomic formats as well as generic, easy to use tab-separated value format for user-provided annotations. ODG is a user-friendly database generation and query tool that adapts to the supplied data to produce a comparative genomic database or multi-layered annotation database. ODG provides rapid comparative genomic annotation and is therefore particularly useful for non-model or

  14. A multi-state model for the reliability assessment of a distributed generation system via universal generating function

    International Nuclear Information System (INIS)

    Li, Yan-Fu; Zio, Enrico

    2012-01-01

    The current and future developments of electric power systems are pushing the boundaries of reliability assessment to consider distribution networks with renewable generators. Given the stochastic features of these elements, most modeling approaches rely on Monte Carlo simulation. The computational costs associated to the simulation approach force to treating mostly small-sized systems, i.e. with a limited number of lumped components of a given renewable technology (e.g. wind or solar, etc.) whose behavior is described by a binary state, working or failed. In this paper, we propose an analytical multi-state modeling approach for the reliability assessment of distributed generation (DG). The approach allows looking to a number of diverse energy generation technologies distributed on the system. Multiple states are used to describe the randomness in the generation units, due to the stochastic nature of the generation sources and of the mechanical degradation/failure behavior of the generation systems. The universal generating function (UGF) technique is used for the individual component multi-state modeling. A multiplication-type composition operator is introduced to combine the UGFs for the mechanical degradation and renewable generation source states into the UGF of the renewable generator power output. The overall multi-state DG system UGF is then constructed and classical reliability indices (e.g. loss of load expectation (LOLE), expected energy not supplied (EENS)) are computed from the DG system generation and load UGFs. An application of the model is shown on a DG system adapted from the IEEE 34 nodes distribution test feeder.

  15. A Low-cost Multi-channel Analogue Signal Generator

    CERN Document Server

    Muller, F; Shen, W; Stamen, R

    2009-01-01

    A scalable multi-channel analogue signal generator is presented. It uses a commercial low-cost graphics card with multiple outputs in a standard PC as signal source. Each color signal serves as independent channel to generate an analogue signal. A custom-built external PCB was developed to adjust the graphics card output voltage levels for a specific task, which needed differential signals. The system furthermore comprises a software package to program the signal shape. The implementation of the signal generator is presented as well as an application where it was successfully utilized.

  16. Detailed Modeling and Irreversible Transfer Process Analysis of a Multi-Element Thermoelectric Generator System

    Science.gov (United States)

    Xiao, Heng; Gou, Xiaolong; Yang, Suwen

    2011-05-01

    Thermoelectric (TE) power generation technology, due to its several advantages, is becoming a noteworthy research direction. Many researchers conduct their performance analysis and optimization of TE devices and related applications based on the generalized thermoelectric energy balance equations. These generalized TE equations involve the internal irreversibility of Joule heating inside the thermoelectric device and heat leakage through the thermoelectric couple leg. However, it is assumed that the thermoelectric generator (TEG) is thermally isolated from the surroundings except for the heat flows at the cold and hot junctions. Since the thermoelectric generator is a multi-element device in practice, being composed of many fundamental TE couple legs, the effect of heat transfer between the TE couple leg and the ambient environment is not negligible. In this paper, based on basic theories of thermoelectric power generation and thermal science, detailed modeling of a thermoelectric generator taking account of the phenomenon of energy loss from the TE couple leg is reported. The revised generalized thermoelectric energy balance equations considering the effect of heat transfer between the TE couple leg and the ambient environment have been derived. Furthermore, characteristics of a multi-element thermoelectric generator with irreversibility have been investigated on the basis of the new derived TE equations. In the present investigation, second-law-based thermodynamic analysis (exergy analysis) has been applied to the irreversible heat transfer process in particular. It is found that the existence of the irreversible heat convection process causes a large loss of heat exergy in the TEG system, and using thermoelectric generators for low-grade waste heat recovery has promising potential. The results of irreversibility analysis, especially irreversible effects on generator system performance, based on the system model established in detail have guiding significance for

  17. Probability of bystander effect induced by alpha-particles emitted by radon progeny using the analytical model of tracheobronchial tree

    International Nuclear Information System (INIS)

    Jovanovic, B.; Nikezic, D.

    2010-01-01

    Radiation-induced biological bystander effects have become a phenomenon associated with the interaction of radiation with cells. There is a need to include the influence of biological effects in the dosimetry of the human lung. With this aim, the purpose of this work is to calculate the probability of bystander effect induced by alpha-particle radiation on sensitive cells of the human lung. Probability was calculated by applying the analytical model cylinder bifurcation, which was created to simulate the geometry of the human lung with the geometric distribution of cell nuclei in the airway wall of the tracheobronchial tree. This analytical model of the human tracheobronchial tree represents the extension of the ICRP 66 model, and follows it as much as possible. Reported probabilities are calculated for various targets and alpha-particle energies. Probability of bystander effect has been calculated for alpha particles with 6 and 7.69 MeV energies, which are emitted in the 222 Rn chain. The application of these results may enhance current dose risk estimation approaches in the sense of the inclusion of the influence of the biological effects. (authors)

  18. Multi-channel grouping techniques for conducting reactor safety studies

    International Nuclear Information System (INIS)

    Waltar, A.E.; Wilburn, N.P.

    1975-01-01

    In conducting safety studies for postulated unprotected accidents in an LMFBR system, it is common practice to employ multi-channel coupled neutronics, thermal hydraulics computer programs such as SAS3A or MELT-III. The multichannel feature of such code systems is important if the natural fuel failure incoherencies and the resulting sodium void/fuel motion reactivity feedbacks--which have strong spatial variations--are to be properly modeled. Because of the large amounts of computer time associated with many channel runs, however, there is a strong incentive to conduct parametric studies with as few channels as possible. The paper presented is focused on methods successfully employed to accomplish this end for a study of the hypothetical unprotected transient overpower accident conducted for the FFTF

  19. A Low-cost Multi-channel Analogue Signal Generator

    CERN Document Server

    Müller, F; The ATLAS collaboration; Shen, W; Stamen, R

    2009-01-01

    A scalable multi-channel analogue signal generator is presented. It uses a commercial low-cost graphics card with multiple outputs in a standard PC as signal source. Each color signal serves as independent channel to generate an analogue signal. A custom-built external PCB was developed to adjust the graphics card output voltage levels for a specific task, which needed differential signals. The system furthermore comprises a software package to program the signal shape. The signal generator was successfully used as independent test bed for the ATLAS Level-1 Trigger Pre-Processor, providing up to 16 analogue signals.

  20. Computed-tomographic and conventional linear-tomographic evaluation of tracheobronchial lesions for laser photoresection

    International Nuclear Information System (INIS)

    Pearlberg, J.L.; Sandler, M.A.; Kvale, P.; Beute, G.H.; Madrazo, B.L.

    1985-01-01

    Laser therapy is a new modality for treatment of airway lesions. The authors examined 18 patients prior to laser photoresection of tracheobronchial lesions. Thirteen had cancers involving the distal trachea, carina, and/or proximal bronchi; five had benign lesions of the middle or proximal trachea. Each patient was examined by conventional linear tomography (CLT) and computed tomography (CT). CT was valuable in patients who had lesions of the distal trachea, carina, and/or proximal bronchi. Its particular usefulness, and its advantage relative to CLT, consisted in its ability to delineate vascular structures adjacent to the planned area of photoresection. Neither CLT nor CT was helpful in evaluation of benign lesions of the proximal trachea

  1. Leveraging multi-generational workforce values in interactive information societies

    Directory of Open Access Journals (Sweden)

    Sophie van der Walt

    2010-08-01

    Full Text Available Background: The success of organisations relies on various factors including the ability of its multi-generational workforce to collaborate within the interactive information society. By developing an awareness of the different values of a diverse workforce, organisations may benefit from diversity. Various diversity factors, such as ethnicity, age and gender, impact on the way people interact, especially in the interactive information society.Objectives: This article advocates the need for generational awareness and addresses how this awareness presents benefits to companies, such as, increased productivity, improved succession planning policies and strategies to recruit and retain a diverse workforce. The research problem is directed at how diversity management influences Traditionalists, Baby Boomers, Generation X and Generation Y in terms of their work performance and co-worker relationships.Method: The research design combines Critical Theory and Generational Theory within the mixed-method paradigm. The sequential exploratory design was decided upon as it studies the unknown relationships between different generations of employees. The literature review was followed by a quantitative empirical research component and data was collected by means of a questionnaire. Results: The findings highlight specific differences between generations regarding their perspectives on work values and co-worker relationships, rewards, work-life balance and retirement.Conclusion: The article concludes with recommendations on the role diversity management plays in terms of work performance and co-worker relationships. By leveraging generational awareness in the interactive information society organizations with a multi-generational workforce will succeed in the competitive business environment.

  2. Studies of plutonium in human tracheobronchial lymph nodes

    International Nuclear Information System (INIS)

    McInroy, J.F.; Stewart, M.W.; Moss, W.D.

    1976-01-01

    Since 1959, tissues from 70 occupationally exposed former employees of the Los Alamos Scientific Laboratory have been examined following autopsy. Exposure in most cases was to inhaled plutonium oxide aerosols. Chemical analyses of selected tissues were performed to determine the amount of plutonium retained in the body at the time of death. On the basis of the measured tissue concentrations of plutonium, extrapolations of total-body burdens were made. Thirty-three of the measured cases had plutonium depositions in the tracheobronchial lymph nodes ranging from 0.1 to 4000 dpm per gram of tissue (0.05 to 1800 pCi/g). The duration of exposures ranged from 4 to 30 years. Microscopic examination of representative sections of these lymph nodes revealed no abnormalities other than those which were directly attributable to the basic disease that caused the demise of the various persons in this study. The size distribution of plutonium particles in nodes from one individual was determined by exposing tissue sections to nuclear track film. The estimated mass median diameter of the particles was 0.3 μm, and the distribution had a geometric standard deviation of 1.6. It is estimated that 95 percent of the individual particles had corresponding plutonium concentrations between 0.001 and 0.22 pCi

  3. TLS for generating multi-LOD of 3D building model

    International Nuclear Information System (INIS)

    Akmalia, R; Setan, H; Majid, Z; Suwardhi, D; Chong, A

    2014-01-01

    The popularity of Terrestrial Laser Scanners (TLS) to capture three dimensional (3D) objects has been used widely for various applications. Development in 3D models has also led people to visualize the environment in 3D. Visualization of objects in a city environment in 3D can be useful for many applications. However, different applications require different kind of 3D models. Since a building is an important object, CityGML has defined a standard for 3D building models at four different levels of detail (LOD). In this research, the advantages of TLS for capturing buildings and the modelling process of the point cloud can be explored. TLS will be used to capture all the building details to generate multi-LOD. This task, in previous works, involves usually the integration of several sensors. However, in this research, point cloud from TLS will be processed to generate the LOD3 model. LOD2 and LOD1 will then be generalized from the resulting LOD3 model. Result from this research is a guiding process to generate the multi-LOD of 3D building starting from LOD3 using TLS. Lastly, the visualization for multi-LOD model will also be shown

  4. TLS for generating multi-LOD of 3D building model

    Science.gov (United States)

    Akmalia, R.; Setan, H.; Majid, Z.; Suwardhi, D.; Chong, A.

    2014-02-01

    The popularity of Terrestrial Laser Scanners (TLS) to capture three dimensional (3D) objects has been used widely for various applications. Development in 3D models has also led people to visualize the environment in 3D. Visualization of objects in a city environment in 3D can be useful for many applications. However, different applications require different kind of 3D models. Since a building is an important object, CityGML has defined a standard for 3D building models at four different levels of detail (LOD). In this research, the advantages of TLS for capturing buildings and the modelling process of the point cloud can be explored. TLS will be used to capture all the building details to generate multi-LOD. This task, in previous works, involves usually the integration of several sensors. However, in this research, point cloud from TLS will be processed to generate the LOD3 model. LOD2 and LOD1 will then be generalized from the resulting LOD3 model. Result from this research is a guiding process to generate the multi-LOD of 3D building starting from LOD3 using TLS. Lastly, the visualization for multi-LOD model will also be shown.

  5. Hybrid 3D visualization of the chest and virtual endoscopy of the tracheobronchial system: possibilities and limitations of clinical application.

    Science.gov (United States)

    Seemann, M D; Claussen, C D

    2001-06-01

    A hybrid rendering method which combines a color-coded surface rendering method and a volume rendering method is described, which enables virtual endoscopic examinations using different representation models. 14 patients with malignancies of the lung and mediastinum (n=11) and lung transplantation (n=3) underwent thin-section spiral computed tomography. The tracheobronchial system and anatomical and pathological features of the chest were segmented using an interactive threshold interval volume-growing segmentation algorithm and visualized with a color-coded surface rendering method. The structures of interest were then superimposed on a volume rendering of the other thoracic structures. For the virtual endoscopy of the tracheobronchial system, a shaded-surface model without color coding, a transparent color-coded shaded-surface model and a triangle-surface model were tested and compared. The hybrid rendering technique exploit the advantages of both rendering methods, provides an excellent overview of the tracheobronchial system and allows a clear depiction of the complex spatial relationships of anatomical and pathological features. Virtual bronchoscopy with a transparent color-coded shaded-surface model allows both a simultaneous visualization of an airway, an airway lesion and mediastinal structures and a quantitative assessment of the spatial relationship between these structures, thus improving confidence in the diagnosis of endotracheal and endobronchial diseases. Hybrid rendering and virtual endoscopy obviate the need for time consuming detailed analysis and presentation of axial source images. Virtual bronchoscopy with a transparent color-coded shaded-surface model offers a practical alternative to fiberoptic bronchoscopy and is particularly promising for patients in whom fiberoptic bronchoscopy is not feasible, contraindicated or refused. Furthermore, it can be used as a complementary procedure to fiberoptic bronchoscopy in evaluating airway stenosis and

  6. Generation and control of multi-scroll chaotic attractors in fractional order systems

    International Nuclear Information System (INIS)

    Ahmad, Wajdi M.

    2005-01-01

    The objective of this paper is twofold: on one hand we demonstrate the generation of multi-scroll attractors in fractional order chaotic systems. Then, we design state feedback controllers to eliminate chaos from the system trajectories. It is demonstrated that modifying the underlying nonlinearity of the fractional chaotic system results in the birth of multiple chaotic attractors, thus forming the so called multi-scroll attractors. The presence of chaotic behavior is evidenced by a positive largest Lyapunov exponent computed for the output time series. We investigate generation and control of multi-scroll attractors in two different models, both of which are fractional order and chaotic: an electronic oscillator, and a mechanical 'jerk' model. The current findings extend previously reported results on generation of n-scroll attractors from the domain of integer order to the domain of fractional order chaotic systems, and addresses the issue of controlling such chaotic behaviors. Our investigations are validated through numerical simulations

  7. Hydrological modeling using a multi-site stochastic weather generator

    Science.gov (United States)

    Weather data is usually required at several locations over a large watershed, especially when using distributed models for hydrological simulations. In many applications, spatially correlated weather data can be provided by a multi-site stochastic weather generator which considers the spatial correl...

  8. Thermal conductivities of single- and multi-layer phosphorene: a molecular dynamics study.

    Science.gov (United States)

    Zhang, Ying-Yan; Pei, Qing-Xiang; Jiang, Jin-Wu; Wei, Ning; Zhang, Yong-Wei

    2016-01-07

    As a new two-dimensional (2D) material, phosphorene has drawn growing attention owing to its novel electronic properties, such as layer-dependent direct bandgaps and high carrier mobility. Herein we investigate the in-plane and cross-plane thermal conductivities of single- and multi-layer phosphorene, focusing on geometrical (sample size, orientation and layer number) and strain (compression and tension) effects. A strong anisotropy is found in the in-plane thermal conductivity with its value along the zigzag direction being much higher than that along the armchair direction. Interestingly, the in-plane thermal conductivity of multi-layer phosphorene is insensitive to the layer number, which is in strong contrast to that of graphene where the interlayer interactions strongly influence the thermal transport. Surprisingly, tensile strain leads to an anomalous increase in the in-plane thermal conductivity of phosphorene, in particular in the armchair direction. Both the in-plane and cross-plane thermal conductivities can be modulated by external strain; however, the strain modulation along the cross-plane direction is more effective and thus more tunable than that along the in-plane direction. Our findings here are of great importance for the thermal management in phosphorene-based nanoelectronic devices and for thermoelectric applications of phosphorene.

  9. Uptake kinetics of relatively insoluble particles by tracheobronchial lymph nodes

    International Nuclear Information System (INIS)

    Thomas, R.G.

    1976-01-01

    Tracheobronchial lymph nodes accumulate a portion of material deposited in the deep lung following inhalation of relatively insoluble particles. Experiments involving a variety of compounds, inhaled singly or repeatedly, indicate that the kinetics of lymph node uptake are fairly independent of particle characteristics and mammalian species. The buildup per unit weight of nodal tissue compared with that of lung tissue, with time, can be represented by a linear logarithmic function. However, since the scatter in experimental points may be large at any given time after inhalation exposure, a number of different kinetic descriptions of uptake can be derived. The logarithmic pattern of accumulation can be approximated over an extended time range (several years) by use of a combination of first-order kinetics of loss from the lung and of buildup in lymph nodes, but it is recognized that the processes are much more complicated than this treatment would indicate. Clearance (loss) from the lymph nodes is not well defined, but this aspect is discussed in light of the kinetic models presented

  10. Multi-Group Library Generation with Explicit Resonance Interference Using Continuous Energy Monte Carlo Calculation

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ho Jin; Cho, Jin Young [KAERI, Daejeon (Korea, Republic of); Kim, Kang Seog [Oak Ridge National Laboratory, Oak Ridge (United States); Hong, Ser Gi [Kyung Hee University, Yongin (Korea, Republic of)

    2016-05-15

    In this study, multi-group cross section libraries for the DeCART code were generated using a new procedure. The new procedure includes generating the RI tables based on the MC calculations, correcting the effective fission product yield calculations, and considering most of the fission products as resonant nuclides. KAERI (Korea Atomic Energy Research Institute) has developed the transport lattice code KARMA (Kernel Analyzer by Ray-tracing Method for fuel Assembly) and DeCART (Deterministic Core Analysis based on Ray Tracing) for a multi-group neutron transport analysis of light water reactors (LWRs). These codes adopt the method of characteristics (MOC) to solve the multi-group transport equation and resonance fixed source problem, the subgroup and the direct iteration method with resonance integral tables for resonance treatment. With the development of the DeCART and KARMA code, KAERI has established its own library generation system for a multi-group transport calculation. In the KAERI library generation system, the multi-group average cross section and resonance integral (RI) table are generated and edited using PENDF (point-wise ENDF) and GENDF (group-wise ENDF) produced by the NJOY code. The new method does not need additional processing because the MC method can handle any geometry information and material composition. In this study, the new method is applied to the dominant resonance nuclide such as U{sup 235} and U{sup 238} and the conventional method is applied to the minor resonance nuclides. To examine the newly generated multi-group cross section libraries, various benchmark calculations such as pin-cell, FA, and core depletion problem are performed and the results are compared with the reference solutions. Overall, the results by the new method agree well with the reference solution. The new procedure based on the MC method were verified and provided the multi-group library that can be used in the SMR nuclear design analysis.

  11. Multi-shocks generation and collapsing instabilities induced by competing nonlinearities

    KAUST Repository

    Crosta, Matteo; Trillo, Stefano; Fratalocchi, Andrea

    2012-01-01

    We investigate dispersive shock dynamics in materials with competing cubic-quintic nonlinearities. Whitham theory of modulation, hydrodynamic analysis and numerics demonstrate a rich physical scenario, ranging from multi-shock generation to collapse.

  12. Next generation multi-material 3D food printer concept

    NARCIS (Netherlands)

    Klomp, D.J.; Anderson, P.D.

    2017-01-01

    3D food printing is a new rapidly developing technology capable of creating food structures that are impossible to create with normal processing techniques. Challenges in this field are creating texture and multi-material food products. To address these challenges a next generation food printer will

  13. Primary tracheobronchial amyloidosis: Two case reports Amiloidose traqueobrônquica primária: A propósito de dois casos clínicos

    Directory of Open Access Journals (Sweden)

    Sandra Saleiro

    2008-07-01

    Full Text Available Primary tracheobronchial amyloidosis is a form of respiratory amyloidosis, characterised by insoluble amyloid fibril proteins deposits along the airways wall. It is an uncommon disease, requiring a tissue sample to establish the definite diagnosis based on specific pathological features. The authors report two cases of tracheobronchial amyloidosis, describing their symptoms and the diagnostic and therapeutic procedures that were performed.A amiloidose traqueobrônquica primária é uma forma de amiloidose respiratória, caracterizada pela presença de depósitos insolúveis de proteína fibrilar amilóide, ao longo da parede das vias aéreas. É uma doença pouco frequente, sendo necessário uma amostra de tecido para estabelecer o diagnóstico definitivo, com base em características histológicas específicas. Os autores relatam dois casos clínicos de amiloidose traqueobrônquica, descrevendo os seus sintomas e os procedimentos diagnósticos e terapêuticos que foram efectuados.

  14. MAIL3.1 : a computer program generating cross section sets for SIMCRI, ANISN-JR, KENO IV, KENO V, MULTI-KENO, MULTI-KENO-2 and MULTI-KENO-3.0

    International Nuclear Information System (INIS)

    Suyama, Kenya; Komuro, Yuichi; Takada, Tomoyuki; Kawasaki, Hiromitsu; Ouchi, Keisuke

    1998-02-01

    This report is a user's manual of the computer program MAIL3.1 which generates various types of cross section sets for neutron transport programs such as SIMCRI, ANISN-JR, KENO IV, KENO V, MULTI-KENO, MULTI-KENO-2 and MULTI-KENO-3.0. MAIL3.1 is a revised version of MAIL3.0 that was opened in 1990. It has all of abilities of MAIL3.0 and has two more functions as shown in following. 1. AMPX-type cross section set generating function for KENO V. 2. Enhanced function for user of 16 group Hansen-Roach library. (author)

  15. MAIL3.1 : a computer program generating cross section sets for SIMCRI, ANISN-JR, KENO IV, KENO V, MULTI-KENO, MULTI-KENO-2 and MULTI-KENO-3.0

    Energy Technology Data Exchange (ETDEWEB)

    Suyama, Kenya; Komuro, Yuichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Takada, Tomoyuki; Kawasaki, Hiromitsu; Ouchi, Keisuke

    1998-02-01

    This report is a user`s manual of the computer program MAIL3.1 which generates various types of cross section sets for neutron transport programs such as SIMCRI, ANISN-JR, KENO IV, KENO V, MULTI-KENO, MULTI-KENO-2 and MULTI-KENO-3.0. MAIL3.1 is a revised version of MAIL3.0 that was opened in 1990. It has all of abilities of MAIL3.0 and has two more functions as shown in following. 1. AMPX-type cross section set generating function for KENO V. 2. Enhanced function for user of 16 group Hansen-Roach library. (author)

  16. On the impact of second generation mating and offspring in multi-generation reproductive toxicity studies on classification and labelling of substances in Europe

    DEFF Research Database (Denmark)

    Rorije, Emiel; Muller, André; Beekhuijzen, Manon E.W.

    2011-01-01

    The possible impact on classification and labelling decisions of effects observed in second generation parental (P1) and offspring (F2) parameters in multi-generation studies was investigated. This was done for 50 substances classified as reproductive toxicants in Europe, for which a multi-genera...... and reduced animal use, provide strong further support for replacement of the classical two-generation reproductive toxicity study by the EOGRTS in regulatory reproductive toxicity assessment....

  17. A methodology for designing flexible multi-generation systems

    DEFF Research Database (Denmark)

    Lythcke-Jørgensen, Christoffer Ernst; Viana Ensinas, Adriano; Münster, Marie

    2016-01-01

    An FMG (flexible multi-generation system) consists of integrated and flexibly operated facilities that provide multiple links between the various layers of the energy system. FMGs may facilitate integration and balancing of fluctuating renewable energy sources in the energy system in a cost...... is based on consideration of the following points: Selection, location and dimensioning of processes; systematic heat and mass integration; flexible operation optimization with respect to both short-term market fluctuations and long-term energy system development; global sensitivity and uncertainty...... analysis; biomass supply chains; variable part-load performance; and multi-objective optimization considering economic and environmental performance. Tested in a case study, the methodology is proved effective in screening the solution space for efficient FMG designs, in assessing the importance...

  18. Research on Shaft Subsynchronous Oscillation Characteristics of Parallel Generators and SSDC Application in Mitigating SSO of Multi-Generators

    Directory of Open Access Journals (Sweden)

    Shen Wang

    2015-02-01

    Full Text Available Subsynchronous oscillation (SSO of generators caused by high voltage direct current (HVDC systems can be solved by applying supplemental subsynchronous damping controller (SSDC. SSDC application in mitigating SSO of single-generator systems has been studied intensively. This paper focuses on SSDC application in mitigating SSO of multi-generator systems. The phase relationship of the speed signals of the generators under their common mechanical natural frequencies is a key consideration in SSDC design. The paper studies in detail the phase relationship of the speed signals of two generators in parallel under their shared mechanical natural frequency, revealing regardless of whether the two generators are identical or not, there always exists a common-mode and an anti-mode under their common natural frequency, and the phase relationship of the speed signals of the generators depends on the extent to which the anti-mode is stimulated. The paper further demonstrates that to guarantee the effectiveness of SSDC, the anti-phase mode component of its input signal should be eliminated. Based on the above analysis, the paper introduces the design process of SSDC for multi-generator systems and verifies its effectiveness through simulation in Power Systems Computer Aided Design/Electromagnetic Transients including Direct Current (PSCAD/EMTDC.

  19. Multi-probe ionization chamber system for nuclear-generated plasma diagnostics

    International Nuclear Information System (INIS)

    Choi, W.Y.; Ellis, W.H.

    1990-01-01

    This paper reports on the pulsed ionization chamber (PIC) plasma diagnostic system used in studies of nuclear seeded plasma kinetics upgraded to increase the capabilities and extend the range of plasma parameter measurements to higher densities and temperatures. The PIC plasma diagnostic chamber has been provided with additional measurement features in the form of conductivity and Langmuir probes, while the overall experimental system has been fully automated, with computerized control, measurement, data acquisition and analysis by means of IEEE-488 (GPIB) bus control and data transfer protocols using a Macintosh series microcomputer. The design and use of a simple TTL switching system enables remote switching among the various GPIB instruments comprising the multi-probe plasma diagnostic system using software, without the need for a microprocessor. The new system will be used to extend the present study of nuclear generated plasma in He, Ar, Xe, fissionable UF 6 and other fluorine containing gases

  20. Multi-Period Portfolio Optimization of Power Generation Assets

    Directory of Open Access Journals (Sweden)

    Barbara Glensk

    2013-01-01

    Full Text Available The liberalization and deregulation of the energy industry in the past decades have been significantly affected by changes in the strategies of energy firms. The traditionally used approach of cost minimization was no longer sufficient, risk and market behavior could no longer be ignored and the need for more appropriate optimization methods for uncertain environments was increased. Meanvariance portfolio (MVP theory is one of the more advanced financial methods that has been successfully applied to the energy sector. Unfortunately, this static approach is inadequate for studying multi-stage investment decision problems. The methodology proposed in this paper considering power generation assets is based on the model introduced by Mulvey, who suggests a reallocation approach using the analysis of various scenarios. The adoption of this methodology to power generation assets allows us to capture the impact of variations in the economic and technical parameters considered. The results of our study show that the application of a model for selection of multi-period portfolio can indeed improve the decision making process. Especially for the case of adding new investments to the portfolio mix, this rebalancing model captures new entries very well. (original abstract

  1. Effects of a single dose of enrofloxacin on body temperature and tracheobronchial neutrophil count in healthy Thoroughbreds premedicated with interferon-α and undergoing long-distance transportation.

    Science.gov (United States)

    Tsuchiya, Takeru; Hobo, Seiji; Endo, Yoshiro; Narita, Shoichi; Sakamoto, Koji

    2012-07-01

    To evaluate effects of a single dose of enrofloxacin (5 mg/kg, IV) on body temperature and tracheobronchial neutrophil count in healthy Thoroughbreds premedicated with interferon-α and undergoing long-distance transportation. 32 healthy Thoroughbreds. All horses received interferon-α (0.5 U/kg, sublingually, q 24 h) as an immunologic stimulant for 2 days before transportation and on the day of transportation. Horses were randomly assigned to receive enrofloxacin (5 mg/kg, IV, once; enrofloxacin group) or saline (0.9% NaCl) solution (50 mL, IV, once; control group) ≤ 1 hour before being transported 1,210 km via commercial vans (duration, approx 26 hours). Before and after transportation, clinical examination, measurement of temperature per rectum, and hematologic analysis were performed for all horses; a tracheobronchial aspirate was collected for neutrophil quantification in 12 horses (6/group). Horses received antimicrobial treatment after transportation if deemed necessary by the attending clinician. No adverse effects were associated with treatment. After transportation, WBC count and serum amyloid A concentration in peripheral blood samples and neutrophil counts in tracheobronchial aspirates were significantly lower in horses of the enrofloxacin group than in untreated control horses. Fever (rectal temperature, ≥ 38.5°C) after transportation was detected in 3 of 16 enrofloxacin group horses and 9 of 16 control horses; additional antimicrobial treatment was required in 2 horses in the enrofloxacin group and 7 horses in the control group. In horses premedicated with interferon-α, enrofloxacin appeared to provide better protection against fever and lower respiratory tract inflammation than did saline solution.

  2. The development of a tissue-engineered tracheobronchial epithelial model using a bilayered collagen-hyaluronate scaffold.

    Science.gov (United States)

    O'Leary, Cian; Cavanagh, Brenton; Unger, Ronald E; Kirkpatrick, C James; O'Dea, Shirley; O'Brien, Fergal J; Cryan, Sally-Ann

    2016-04-01

    Today, chronic respiratory disease is one of the leading causes of mortality globally. Epithelial dysfunction can play a central role in its pathophysiology. The development of physiologically-representative in vitro model systems using tissue-engineered constructs might improve our understanding of epithelial tissue and disease. This study sought to engineer a bilayered collagen-hyaluronate (CHyA-B) scaffold for the development of a physiologically-representative 3D in vitro tracheobronchial epithelial co-culture model. CHyA-B scaffolds were fabricated by integrating a thin film top-layer into a porous sub-layer with lyophilisation. The film layer firmly connected to the sub-layer with delamination occurring at stresses of 12-15 kPa. Crosslinked scaffolds had a compressive modulus of 1.9 kPa and mean pore diameters of 70 μm and 80 μm, depending on the freezing temperature. Histological analysis showed that the Calu-3 bronchial epithelial cell line attached and grew on CHyA-B with adoption of an epithelial monolayer on the film layer. Immunofluorescence and qRT-PCR studies demonstrated that the CHyA-B scaffolds facilitated Calu-3 cell differentiation, with enhanced mucin expression, increased ciliation and the formation of intercellular tight junctions. Co-culture of Calu-3 cells with Wi38 lung fibroblasts was achieved on the scaffold to create a submucosal tissue analogue of the upper respiratory tract, validating CHyA-B as a platform to support co-culture and cellular organisation reminiscent of in vivo tissue architecture. In summary, this study has demonstrated that CHyA-B is a promising tool for the development of novel 3D tracheobronchial co-culture in vitro models with the potential to unravel new pathways in drug discovery and drug delivery. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Numerical investigation of inspiratory airflow in a realistic model of the human tracheobronchial airways and a comparison with experimental results.

    Science.gov (United States)

    Elcner, Jakub; Lizal, Frantisek; Jedelsky, Jan; Jicha, Miroslav; Chovancova, Michaela

    2016-04-01

    In this article, the results of numerical simulations using computational fluid dynamics (CFD) and a comparison with experiments performed with phase Doppler anemometry are presented. The simulations and experiments were conducted in a realistic model of the human airways, which comprised the throat, trachea and tracheobronchial tree up to the fourth generation. A full inspiration/expiration breathing cycle was used with tidal volumes 0.5 and 1 L, which correspond to a sedentary regime and deep breath, respectively. The length of the entire breathing cycle was 4 s, with inspiration and expiration each lasting 2 s. As a boundary condition for the CFD simulations, experimentally obtained flow rate distribution in 10 terminal airways was used with zero pressure resistance at the throat inlet. CCM+ CFD code (Adapco) was used with an SST k-ω low-Reynolds Number RANS model. The total number of polyhedral control volumes was 2.6 million with a time step of 0.001 s. Comparisons were made at several points in eight cross sections selected according to experiments in the trachea and the left and right bronchi. The results agree well with experiments involving the oscillation (temporal relocation) of flow structures in the majority of the cross sections and individual local positions. Velocity field simulation in several cross sections shows a very unstable flow field, which originates in the tracheal laryngeal jet and propagates far downstream with the formation of separation zones in both left and right airways. The RANS simulation agrees with the experiments in almost all the cross sections and shows unstable local flow structures and a quantitatively acceptable solution for the time-averaged flow field.

  4. The value of oropharyngoesophageal scintigraphy in the management of aspiration into the tracheobronchial tree in neurological patients.

    Science.gov (United States)

    Grosso, M; Fattori, B; Volterrani, D; Chondrogiannis, S; Boni, G; Nacci, A; Marzola, M C; Rubello, D

    2015-01-01

    Dysphagia and bolus aspiration are two of the most frequent and invalidating symptoms of various neurological diseases. Swallowing disorders often lead to tracheobronchial aspiration with consequent pneumonia episodes. Aspiration pneumonia per se constitutes the most frequent cause of death in these patients, with mortality rate ranging from 20% to 62%. Oropharyngoesophageal scintigraphy (OPES) permits functional quantitative assessment of the different stages of swallowing, together with the detection and quantitative measurement of bolus aspiration. In this work, we analyzed the role of OPES in patients with different neurological conditions to evaluate swallowing and to detect and quantify bolus aspiration. We enrolled 43 neurological patients (25 women and 18 men, mean age 67.3±12.4 yr) complaining of dysphagia with suspected inhalation. All patients underwent OPES with (99m)Tc-nanocolloid using a liquid bolus first, followed by a semi-solid bolus. We evaluated the following parameters: Oral, Pharyngeal and Esophageal Transit Time, Oro-Pharyngeal Retention Index, Esophageal Emptying Rate, and Aspiration Rate (% AR). OPES detected some airway aspiration in 26/43 patients. 19 patients had tracheal aspiration (with a mean 18.1% AR) and the remaining 7 patients had bilateral broncho-pulmonary aspiration (mean 44.9% AR). OPES is a feasible, repeatable and noninvasive method that allows quantitative assessment of bolus aspiration into the tracheobronchial tract, thus representing a useful and accurate tool to guide the most appropriate treatment and to monitor response to therapy in neurological patients with dysphagia. Copyright © 2015 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

  5. Multi-point laser spark generation for internal combustion engines using a spatial light modulator

    International Nuclear Information System (INIS)

    Lyon, Elliott; Kuang, Zheng; Dearden, Geoff; Cheng, Hua; Page, Vincent; Shenton, Tom

    2014-01-01

    This paper reports on a technique demonstrating for the first time successful multi-point laser-induced spark generation, which is variable in three dimensions and derived from a single laser beam. Previous work on laser ignition of internal combustion engines found that simultaneously igniting in more than one location resulted in more stable and faster combustion – a key potential advantage over conventional spark ignition. However, previous approaches could only generate secondary foci at fixed locations. The work reported here is an experimental technique for multi-point laser ignition, in which several sparks with arbitrary spatial location in three dimensions are created by variable diffraction of a pulsed single laser beam source and transmission through an optical plug. The diffractive multi-beam arrays and patterns are generated using a spatial light modulator on which computer generated holograms are displayed. A gratings and lenses algorithm is used to accurately modulate the phase of the input laser beam and create multi-beam output. The underpinning theory, experimental arrangement and results obtained are presented and discussed. (paper)

  6. Effects of multi-photon interferences from internally generated fields in strongly resonant systems

    International Nuclear Information System (INIS)

    Deng, Lu; Payne, Marvin G.; Garrett, William R.

    2006-01-01

    In studies of various nonlinear optical phenomena, strong resonant features in the atomic or molecular response to multi-photon driven processes have been used to greatly enhance the visibility of otherwise weak higher-order processes. However, there are well defined circumstances where a multi-photon-resonant response of a target system leads to the generation of one or more new electromagnetic fields that can drastically change the overall system response from what would be expected from the imposed laser fields alone. New effects can occur and dominate some aspects of the nonlinear optical response because of the constructive or destructive interference between transition amplitudes along multiple excitation pathways between a given set of optically coupled states, where one of the pathways involve internally generated field(s). Under destructive interference some resonant enhancements can become completely canceled (suppressed). This review focuses on the class of optical interference effects associated with internally generated fields, that have been found to be capable of influencing a very significant number of basic physical phenomena in gas or vapor phase systems. It provides a historical overview of experimental and theoretical developments and a modern understanding of the underlying physics and its various manifestations that include: suppression of multi-photon excitation processes, suppression of stimulated emissions (Raman, hyper-Raman, and optically pumped stimulated emissions), saturation of parametric wave-mixing, pressure and beam-geometry dependent shifting of multi-photon-resonant absorption lines, and the suppression of Autler-Townes splitting and ac-stark shifts. Additionally, optical interference effects in some modern contexts, such as achieving multi-photon induced transparency, establishing single-photon self-interference based induced transparency, and generating entangled single photon states, are reviewed

  7. Multi-objective optimal strategy for generating and bidding in the power market

    International Nuclear Information System (INIS)

    Peng Chunhua; Sun Huijuan; Guo Jianfeng; Liu Gang

    2012-01-01

    Highlights: ► A new benefit/risk/emission comprehensive generation optimization model is established. ► A hybrid multi-objective differential evolution optimization algorithm is designed. ► Fuzzy set theory and entropy weighting method are employed to extract the general best solution. ► The proposed approach of generating and bidding is efficient for maximizing profit and minimizing both risk and emissions. - Abstract: Based on the coordinated interaction between units output and electricity market prices, the benefit/risk/emission comprehensive generation optimization model with objectives of maximal profit and minimal bidding risk and emissions is established. A hybrid multi-objective differential evolution optimization algorithm, which successfully integrates Pareto non-dominated sorting with differential evolution algorithm and improves individual crowding distance mechanism and mutation strategy to avoid premature and unevenly search, is designed to achieve Pareto optimal set of this model. Moreover, fuzzy set theory and entropy weighting method are employed to extract one of the Pareto optimal solutions as the general best solution. Several optimization runs have been carried out on different cases of generation bidding and scheduling. The results confirm the potential and effectiveness of the proposed approach in solving the multi-objective optimization problem of generation bidding and scheduling. In addition, the comparison with the classical optimization algorithms demonstrates the superiorities of the proposed algorithm such as integrality of Pareto front, well-distributed Pareto-optimal solutions, high search speed.

  8. Severe tracheobronchial compression in a patient with Turner′s syndrome undergoing repair of a complex aorto-subclavian aneurysm: Anesthesia perspectives

    Directory of Open Access Journals (Sweden)

    Christopher C .C. Hudson

    2014-01-01

    Full Text Available We present a case of severe tracheobronchial compression from a complex aorto-subclavian aneurysm in a patient with Turner′s syndrome undergoing open surgical repair. Significant airway compression is a challenging situation and requires careful preoperative preparation, maintenance of spontaneous breathing when possible, and consideration of having an alternative source of oxygenation and circulation established prior to induction of general anesthesia. Cardiopulmonary monitoring is essential for safe general anesthesia and diagnosis of unexpected intraoperative events.

  9. Mechanisms of asbestos-induced squamous metaplasia in tracheobronchial epithelial cells

    International Nuclear Information System (INIS)

    Cameron, G.; Woodworth, C.D.; Edmondson, S.; Mossman, B.T.

    1989-01-01

    Within 1 to 4 weeks after exposure to asbestos, differentiated rodent and human tracheobronchial epithelial cells in organ culture undergo squamous metaplasia, a putative preneoplastic lesion characterized by conversion of mucociliary cell types to keratinizing cells. The exogenous addition of retinal acetate (RA) to culture medium of hamster tracheal organ cultures reverses preestablished, asbestos-induced squamous metaplasia, although data suggest that the effectiveness of RA decreases as the length of time between exposure to asbestos and initial application of RA increases. Difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase (ODC), inhibits squamous metaplasia caused by asbestos or vitamin A deficiency, whereas addition of methylglyoxal bis(guanyl-hydrazone) (MGBG), a structural analog of spermidine and inhibitor of S-adenosylmethionine decarboxylase, causes an enhancement of metaplasia under both circumstances. Basal cell hyperplasia and increased incorporation of 3 H-thymidine by tracheal epithelial cells also are seen after addition of the polyamines, putrescine or spermidine, to tracheal organ cultures, an observation supporting the importance of polyamines in the development of this lesion. The use of retinoids and inhibitors of ODC could be promising as preventive and/or therapeutic approaches for individuals at high risk for development of asbestos-associated diseases

  10. Leveraging multi-generational workforce values in interactive information societies

    Directory of Open Access Journals (Sweden)

    Sophie van der Walt

    2010-11-01

    Objectives: This article advocates the need for generational awareness and addresses how this awareness presents benefits to companies, such as, increased productivity, improved succession planning policies and strategies to recruit and retain a diverse workforce. The research problem is directed at how diversity management influences Traditionalists, Baby Boomers, Generation X and Generation Y in terms of their work performance and co-worker relationships. Method: The research design combines Critical Theory and Generational Theory within the mixed-method paradigm. The sequential exploratory design was decided upon as it studies the unknown relationships between different generations of employees. The literature review was followed by a quantitative empirical research component and data was collected by means of a questionnaire. Results: The findings highlight specific differences between generations regarding their perspectives on work values and co-worker relationships, rewards, work-life balance and retirement. Conclusion: The article concludes with recommendations on the role diversity management plays in terms of work performance and co-worker relationships. By leveraging generational awareness in the interactive information society organizations with a multi-generational workforce will succeed in the competitive business environment.

  11. Multi-generation cadmium acclimation and tolerance in Daphnia magna Straus

    International Nuclear Information System (INIS)

    Muyssen, Brita T.A.; Janssen, Colin R.

    2004-01-01

    The cladoceran Daphnia magna was acclimated for seven generations to cadmium concentrations ranging from 0 (control) to 250 μg/l Cd (corresponding to a free ion activity of 4.60 nM Cd 2+ ). Acute and chronic cadmium tolerance as well as cadmium accumulation were monitored as a function of acclimation time. After two to three generations of acclimation to concentrations ranging from 0.23 to 1.11 nM Cd 2+ increases in acute tolerance were maximal (factor 7.2) and significant. Acclimation for seven generations to the same acclimation concentrations did result in an increased chronic cadmium tolerance (21 days EC 50 values increased). Organisms acclimated to 1.93 nM Cd 2+ were equally or more sensitive than non-acclimated daphnids in acute and chronic toxicity tests. Cadmium contents in D. magna increased significantly as a function of the acclimation concentration. Maximum body burdens of 236±30 μg Cd/g dry weight were measured in organisms exposed to 4.60 nM Cd 2+ , but detoxification mechanisms were only successful up to 82±20 μg Cd/g dry weight as this concentration did not cause major decreases in survival and reproduction in chronic toxicity tests. As the potential positive effect of acclimation on cadmium tolerance disappeared with successive acclimation generations and increasing acclimation concentrations, it is concluded that multi-generation acclimation studies are important for the evaluation of the long-term effects of environmental toxicants. - Multi-generation acclimation studies are important for evaluating long-term effects of aquatic pollutants

  12. Multi-Generation Concentrating Solar-Hydrogen Power System for Sustainable Rural Development

    Energy Technology Data Exchange (ETDEWEB)

    Krothapalli, A.; Greska, B.

    2007-07-01

    This paper describes an energy system that is designed to meet the demands of rural populations that currently have no access to grid-connected electricity. Besides electricity, it is well recognized that rural populations need at least a centralized refrigeration system for storage of medicines and other emergency supplies, as well as safe drinking water. Here we propose a district system that will employ a multi-generation concentrated solar power (CSP) system that will generate electricity and supply the heat needed for both absorption refrigeration and membrane distillation (MD) water purification. The electricity will be used to generate hydrogen through highly efficient water electrolysis and individual households can use the hydrogen for generating electricity, via affordable proton exchange membrane (PEM) fuel cells, and as a fuel for cooking. The multi-generation system is being developed such that its components will be easy to manufacture and maintain. As a result, these components will be less efficient than their typical counterparts but their low cost-to-efficiency ratio will allow for us to meet our installation cost goal of $1/Watt for the entire system. The objective of this paper is to introduce the system concept and discuss the system components that are currently under development. (auth)

  13. Optimal Golomb Ruler Sequences Generation for Optical WDM Systems: A Novel Parallel Hybrid Multi-objective Bat Algorithm

    Science.gov (United States)

    Bansal, Shonak; Singh, Arun Kumar; Gupta, Neena

    2017-02-01

    In real-life, multi-objective engineering design problems are very tough and time consuming optimization problems due to their high degree of nonlinearities, complexities and inhomogeneity. Nature-inspired based multi-objective optimization algorithms are now becoming popular for solving multi-objective engineering design problems. This paper proposes original multi-objective Bat algorithm (MOBA) and its extended form, namely, novel parallel hybrid multi-objective Bat algorithm (PHMOBA) to generate shortest length Golomb ruler called optimal Golomb ruler (OGR) sequences at a reasonable computation time. The OGRs found their application in optical wavelength division multiplexing (WDM) systems as channel-allocation algorithm to reduce the four-wave mixing (FWM) crosstalk. The performances of both the proposed algorithms to generate OGRs as optical WDM channel-allocation is compared with other existing classical computing and nature-inspired algorithms, including extended quadratic congruence (EQC), search algorithm (SA), genetic algorithms (GAs), biogeography based optimization (BBO) and big bang-big crunch (BB-BC) optimization algorithms. Simulations conclude that the proposed parallel hybrid multi-objective Bat algorithm works efficiently as compared to original multi-objective Bat algorithm and other existing algorithms to generate OGRs for optical WDM systems. The algorithm PHMOBA to generate OGRs, has higher convergence and success rate than original MOBA. The efficiency improvement of proposed PHMOBA to generate OGRs up to 20-marks, in terms of ruler length and total optical channel bandwidth (TBW) is 100 %, whereas for original MOBA is 85 %. Finally the implications for further research are also discussed.

  14. Generation and measurement of multi megagauss fields in inertial ...

    Indian Academy of Sciences (India)

    We present here the development of a facility to generate high (multi megagauss) magnetic field of 4 to 5 s rise time, using inertial magnets. The facility includes a low inductance, high current capacitor bank (280 kJ/40 kV) and an inertial magnet, which is a copper disk machined to have a keyhole in it. As the high current ...

  15. Cytokine and chemokine mRNA expression profiles in tracheobronchial lymph nodes from pigs singularly infected or coinfected with porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae (MHYO)

    Science.gov (United States)

    The objective of this study was to determine cytokine and chemokine mRNA expression profiles in tracheobronchial lymph nodes from pigs singularly infected with porcine circovirus type 2 (PCV2), Mycoplasma hyopneumoniae (MHYO), or coinfected with both. Twenty-eight pigs were randomly assigned to one ...

  16. Tracheobronchial and Alveolar Particle Surface Area Doses in Smokers

    Directory of Open Access Journals (Sweden)

    Fernanda Carmen Fuoco

    2017-01-01

    Full Text Available Cigarette smoke is the main cause of lung cancer events. Mainstream cigarette smoke (MSS is a direct concern for smokers, but also the secondhand smoke (SHS contributes to the smoker exposure. In addition, smoker exposure is affected by the “free-smoke” particle exposure (B, related to the micro-environments where smokers spend time. The aim of this paper is to evaluate the daily alveolar and tracheobronchial deposited fractions of airborne particles for smokers as the sum of these three contributions: MSS, SHS, and B. Measurements of particle surface area distributions in the MSS were performed through a Scanning Mobility Particle Sizer, an Aerodynamic Particle Sizer, and a Thermo-dilution system on five types of conventional cigarettes. A Monte Carlo method was then applied to evaluate the most probable value of dose received during the inhalation of MSS by smokers. Measurements of particle concentrations in SHS and at the “free-smoke” particle background (B were performed through 24-h monitoring at a personal scale of adult smoker through hand-held devices. This paper found that the total daily deposited dose for typical smokers was 1.03 × 105 mm2·day−1. The main contribution of such a huge daily dose was addressable to the MSS (98% while SHS contributed 1.1%, increasing up to 2% for people smoking only while traveling in a car.

  17. Successful Use of Extracorporeal Life Support after Double Traumatic Tracheobronchial Injury in a Patient with Severe Acute Asthma

    Directory of Open Access Journals (Sweden)

    Xavier Valette

    2011-01-01

    Full Text Available We report the case of an asthmatic patient with blunt trachea and left main bronchus injuries who developed acute severe asthma after surgical repair. Despite medical treatment and ventilatory support, asthma persisted with high airway pressures and severe respiratory acidosis. We proposed venovenous extracorporeal life support for CO2 removal which allowed arterial blood gas normalization and airway pressures decrease. Extracorporeal life support was removed on day five after medical treatment of acute severe asthma. So we report the successful use of extracorporeal life support for operated double blunt tracheobronchial injury with acute severe asthma.

  18. Preparation of multi-layer film consisting of hydrogen-free DLC and nitrogen-containing DLC for conductive hard coating

    Science.gov (United States)

    Iijima, Yushi; Harigai, Toru; Isono, Ryo; Degai, Satoshi; Tanimoto, Tsuyoshi; Suda, Yoshiyuki; Takikawa, Hirofumi; Yasui, Haruyuki; Kaneko, Satoru; Kunitsugu, Shinsuke; Kamiya, Masao; Taki, Makoto

    2018-01-01

    Conductive hard-coating films have potential application as protective films for contact pins used in the electrical inspection process for integrated circuit chips. In this study, multi-layer diamond-like carbon (DLC) films were prepared as conductive hard-coating films. The multi-layer DLC films consisting of DLC and nitrogen-containing DLC (N-DLC) film were prepared using a T-shape filtered arc deposition method. Periodic DLC/N-DLC four-layer and eight-layer films had the same film thickness by changing the thickness of each layer. In the ball-on-disk test, the N-DLC mono-layer film showed the highest wear resistance; however, in the spherical polishing method, the eight-layer film showed the highest polishing resistance. The wear and polishing resistance and the aggressiveness against an opponent material of the multi-layer DLC films improved by reducing the thickness of a layer. In multi-layer films, the soft N-DLC layer between hard DLC layers is believed to function as a cushion. Thus, the tribological properties of the DLC films were improved by a multi-layered structure. The electrical resistivity of multi-layer DLC films was approximately half that of the DLC mono-layer film. Therefore, the periodic DLC/N-DLC eight-layer film is a good conductive hard-coating film.

  19. High conductivity and transparent aluminum-based multi-layer source/drain electrodes for thin film transistors

    Science.gov (United States)

    Yao, Rihui; Zhang, Hongke; Fang, Zhiqiang; Ning, Honglong; Zheng, Zeke; Li, Xiaoqing; Zhang, Xiaochen; Cai, Wei; Lu, Xubing; Peng, Junbiao

    2018-02-01

    In this study, high conductivity and transparent multi-layer (AZO/Al/AZO-/Al/AZO) source/drain (S/D) electrodes for thin film transistors were fabricated via conventional physical vapor deposition approaches, without toxic elements or further thermal annealing process. The 68 nm-thick multi-layer films with excellent optical properties (transparency: 82.64%), good electrical properties (resistivity: 6.64  ×  10-5 Ω m, work function: 3.95 eV), and superior surface roughness (R q   =  0.757 nm with scanning area of 5  ×  5 µm2) were fabricated as the S/D electrodes. Significantly, comprehensive performances of AZO films are enhanced by the insertion of ultra-thin Al layers. The optimal transparent TFT with this multi-layer S/D electrodes exhibited a decent electrical performance with a saturation mobility (µ sat) of 3.2 cm2 V-1 s-1, an I on/I off ratio of 1.59  ×  106, a subthreshold swing of 1.05 V/decade. The contact resistance of AZO/Al/AZO/Al/AZO multi-layer electrodes is as low as 0.29 MΩ. Moreover, the average visible light transmittance of the unpatterned multi-layers constituting a whole transparent TFT could reach 72.5%. The high conductivity and transparent multi-layer S/D electrodes for transparent TFTs possessed great potential for the applications of the green and transparent displays industry.

  20. Cultural Transmission and Evolution of Melodic Structures in Multi-generational Signaling Games.

    Science.gov (United States)

    Lumaca, Massimo; Baggio, Giosuè

    2017-01-01

    It has been proposed that languages evolve by adapting to the perceptual and cognitive constraints of the human brain, developing, in the course of cultural transmission, structural regularities that maximize or optimize learnability and ease of processing. To what extent would perceptual and cognitive constraints similarly affect the evolution of musical systems? We conducted an experiment on the cultural evolution of artificial melodic systems, using multi-generational signaling games as a laboratory model of cultural transmission. Signaling systems, using five-tone sequences as signals, and basic and compound emotions as meanings, were transmitted from senders to receivers along diffusion chains in which the receiver in each game became the sender in the next game. During transmission, structural regularities accumulated in the signaling systems, following principles of proximity, symmetry, and good continuation. Although the compositionality of signaling systems did not increase significantly across generations, we did observe a significant increase in similarity among signals from the same set. We suggest that our experiment tapped into the cognitive and perceptual constraints operative in the cultural evolution of musical systems, which may differ from the mechanisms at play in language evolution and change.

  1. Experiences of Adult Students in Multi-Generational Community College Classrooms

    Science.gov (United States)

    Clemente, Kathleen Ann

    2010-01-01

    This qualitative study is a basic interpretative inquiry studying the experiences of fourteen adult students 45 years of age or older in a multi-generational community college classroom. The study is informed by social constructivism, social constructionism and andragogy. It focused on how students viewed their experiences in the…

  2. Characteristics of Patient-Centered Medical Home Initiatives that Generated Savings for Medicare: a Qualitative Multi-Case Analysis.

    Science.gov (United States)

    Burton, Rachel A; Lallemand, Nicole M; Peters, Rebecca A; Zuckerman, Stephen

    2018-02-05

    Through the Multi-Payer Advanced Primary Care Practice (MAPCP) Demonstration, Medicare, Medicaid, and private payers offered supplemental payments to 849 primary care practices that became patient-centered medical homes (PCMHs) in eight states; practices also received technical assistance and data reports. Average Medicare payments were capped at $10 per beneficiary per month in each state. Since there was variation in the eight participating states' demonstration designs, experiences, and outcomes, we conducted a qualitative multi-case analysis to identify the key factors that differentiated states that were estimated to have generated net savings for Medicare from states that did not. States' MAPCP Demonstration initiatives were comprehensively profiled in case studies based on secondary document review, three rounds of annual interviews with state staff, payers, practices, and other stakeholders, and other data sources. Case study findings were summarized in a case-ordered predictor-outcome matrix, which identified the presence or absence of key demonstration design features and experiences and arrayed states based on the amount of net savings or losses they generated for Medicare. We then used this matrix to identify initiative features that were present in at least three of the four states that generated net savings and absent from at least three of the four states that did not generate savings. A majority of the states that generated net savings: required practices to be recognized PCMHs to enter the demonstration, did not allow late entrants into the demonstration, used a consistent demonstration payment model across participating payers, and offered practices opportunities to earn performance bonuses. Practices in states that generated net savings also tended to report receiving the demonstration payments and bonuses they expected to receive, without any issues. Designers of future PCMH initiatives may increase their likelihood of generating net savings by

  3. The effect of functionalization on structure and electrical conductivity of multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Lau, Cher Hon; Cervini, Raoul; Clarke, Stephen R.; Markovic, Milena Ginic; Matisons, Janis G.; Hawkins, Stephen C.; Huynh, Chi P.; Simon, George P.

    2008-01-01

    Carbon nanotubes (CNTs) are of interest in many areas of nanotechnology and used in a number of novel applications. However effective dispersion remains a problem and one solution is to functionalize the nanotubes. Any functionalization that is undertaken must preferably not influence other key properties such as strength and electrical conductivity. In this work, multi-walled CNTs are functionalized for comparison, using a range of oxidative techniques, including thermal treatment, acid reflux, and dry UV-ozonolysis. The effects of these treatments on the multi-walled carbon nanotubes (MWCNTs) and their electrical properties were characterized using a range of surface and compositional techniques. The electrical conductivity of MWCNTs was found to increase with functionalization in all cases, and dry UV-ozonolysis was shown to be the treatment technique which best increased conductivity, whilst at the same time maintaining the structural integrity of the nanotubes, even though the level of modification was less than by the other treatment methods.

  4. Entropy generation by nanofluid with variable thermal conductivity ...

    African Journals Online (AJOL)

    The entropy generation by nanofluid with variable thermal conductivity and viscosity of assisted convective flow across a riser pipe of a horizontal flat plate solar collector is investigated numerically. The water based nanofluid with copper nanoparticles is used as the working fluid inside the fluid passing riser pipe.

  5. Multi-period multi-objective electricity generation expansion planning problem with Monte-Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Tekiner, Hatice [Industrial Engineering, College of Engineering and Natural Sciences, Istanbul Sehir University, 2 Ahmet Bayman Rd, Istanbul (Turkey); Coit, David W. [Department of Industrial and Systems Engineering, Rutgers University, 96 Frelinghuysen Rd., Piscataway, NJ (United States); Felder, Frank A. [Edward J. Bloustein School of Planning and Public Policy, Rutgers University, Piscataway, NJ (United States)

    2010-12-15

    A new approach to the electricity generation expansion problem is proposed to minimize simultaneously multiple objectives, such as cost and air emissions, including CO{sub 2} and NO{sub x}, over a long term planning horizon. In this problem, system expansion decisions are made to select the type of power generation, such as coal, nuclear, wind, etc., where the new generation asset should be located, and at which time period expansion should take place. We are able to find a Pareto front for the multi-objective generation expansion planning problem that explicitly considers availability of the system components over the planning horizon and operational dispatching decisions. Monte-Carlo simulation is used to generate numerous scenarios based on the component availabilities and anticipated demand for energy. The problem is then formulated as a mixed integer linear program, and optimal solutions are found based on the simulated scenarios with a combined objective function considering the multiple problem objectives. The different objectives are combined using dimensionless weights and a Pareto front can be determined by varying these weights. The mathematical model is demonstrated on an example problem with interesting results indicating how expansion decisions vary depending on whether minimizing cost or minimizing greenhouse gas emissions or pollutants is given higher priority. (author)

  6. A multi-function IEC 61850 packet generator based on FPGA

    International Nuclear Information System (INIS)

    Wei, Wei; Li, Hong-bin; Cheng, Han-miao

    2016-01-01

    An IEC 61850 packet generator is used to produce IEC 61850-9-2 packets by simulating the merging unit and testing the IEC 61850 digital device. While the existing IEC packet generator can produce ideal digital without any noise, it does not take into account the fact that the merging unit output signal packets will be inevitably superimposed with noise. Since the International Electrical Commission standard of the electronic current transformer specifies the minimum output signal-to-noise ratio of the merging unit to be 30 dB, and the signal superimposed with noise will influence the operation performance of the digital device, it is necessary to design a multi-function IEC 61850-9-2 packet generator for a digital device test. Therefore, in this paper, a multi-function IEC 61850 packet generator has been developed, which not only can output various IEC 61850-9-2 packets, but also can add white Gaussian noise to the signal for digital device testing. By testing three digital electricity meters from different manufacturers, we showed that the error of the digital electricity meter is significantly larger when the signal packet is superimposed with noise. Also when the signal-to-noise ration is 30 dB, the error of one of the meters exceeds the allowed range of the accuracy class. This indicates that the noise testing and the noise setting function of the system has an important role in the testing of a digital device. (paper)

  7. Multi-Objective Sensitivity Analyses for Power Generation Mix: Malaysia Case Study

    OpenAIRE

    Siti Mariam Mohd Shokri; Nofri Yenita Dahlan; Hasmaini Mohamad

    2017-01-01

    This paper presents an optimization framework to determine long-term optimal generation mix for Malaysia Power Sector using Dynamic Programming (DP) technique. Several new candidate units with a pre-defined MW capacity were included in the model for generation expansion planning from coal, natural gas, hydro and renewable energy (RE). Four objective cases were considered, 1) economic cost, 2) environmental, 3) reliability and 4) multi-objectives that combining the three cases. Results show th...

  8. Leveraging multi-generational workforce values in interactive information societies

    OpenAIRE

    Sophie van der Walt; Tanya du Plessis

    2010-01-01

    Background: The success of organisations relies on various factors including the ability of its multi-generational workforce to collaborate within the interactive information society. By developing an awareness of the different values of a diverse workforce, organisations may benefit from diversity. Various diversity factors, such as ethnicity, age and gender, impact on the way people interact, especially in the interactive information society.Objectives: This article advocates the need for g...

  9. Stent implantation into the tracheo-bronchial system in rabbits: histopathologic sequelae in bare metal vs. drug-eluting stents.

    Science.gov (United States)

    Sigler, Matthias; Klötzer, Julia; Quentin, Thomas; Paul, Thomas; Möller, Oliver

    2015-12-01

    Stent implantation into the tracheo-bronchial system may be life-saving in selected pediatric patients with otherwise intractable stenosis of the upper airways. Following implantation, significant tissue proliferation may occur, requiring re-interventions. We sought to evaluate the effect of immunosuppressive coating of the stents on the extent of tissue proliferation in an animal model. Bare metal and sirolimus-coated stents (Bx Sonic and Cypher Select, Johnson & Johnson, Cordis) were implanted into non-stenotic lower airways of New Zealand white rabbits (weight 3.1 to 4.8 kg). Three stents with sirolimus coating and six bare metal stents could be analyzed by means of histology and immunohistochemistry 12 months after implantation. On a macroscopic evaluation, all stents were partially covered with a considerable amount of whitish tissue. Histologically, these proliferations contained fiber-rich connective tissue and some fibromuscular cells without significant differences between both stent types. The superficial tissue layer was formed by typical respiratory epithelium and polygonal cells. Abundant lymphocyte infiltrations and moderate granulocyte infiltrations were found in both groups correspondingly, whereas foreign-body reaction was more pronounced around sirolimus-eluting stents. After stent implantation in the tracheo-bronchial system of rabbits, we found tissue reactions comparable to those seen after stent implantation into the vascular system. There was no difference between coated and uncoated stents with regard to quality and quantity of tissue proliferation. We found, however, a significantly different inflammatory reaction with a more pronounced foreign-body reaction in sirolimus-coated stents. In our small series, drug-eluting stents did not exhibit any benefit over bare metal stents in an experimental setting.

  10. Benign tracheobronchial stenoses: changes in short-term and long-term pulmonary function testing after expandable metallic stent placement.

    Science.gov (United States)

    Gotway, Michael B; Golden, Jeffrey A; LaBerge, Jeanne M; Webb, W Richard; Reddy, Gautham P; Wilson, Mark W; Kerlan, Robert K; Gordon, Roy L

    2002-01-01

    To determine the short- and long-term improvement in airflow dynamics in patients undergoing tracheobronchial stent placement for benign airway stenoses. Twenty-two patients underwent 34 tracheal and/or bronchial stent placement procedures for benign airway stenoses and had the results of pulmonary function tests available. Stent placement indications included bronchomalacia after lung transplantation (n = 11), postintubation stenoses (n = 6), relapsing polychondritis (n = 2), and 1 each of tracheomalacia, tracheal compression, and histoplasmosis. Six patients underwent more than one stent placement procedure (range: 2-7 procedures). The mean forced expiratory volume in one second (FEV(1) ), forced expiratory flow rate in the midportion of the forced vital capacity curve (FEF(25-75) ), forced vital capacity, and peak flow (PF) rate obtained before stent placement were compared with those immediately after stent placement and with those measurements most remote from stent placement using the paired two-tailed test. All patients reported improved respiratory function immediately after stent placement. The mean FEV(1), FEF(25-75), and PF rate improved significantly (p stent placement. On long-term follow-up averaging 15 months after stent placement, these parameters declined despite patients' subjective sense of improvement. Segregating the population into transplant and nontransplant airway stenosis etiologies, however, FEF(25-75) and PF rate remained significantly improved (p = 0.045, p = 0.027, respectively), over the long term for the latter. FEV increased after subsequent stent placements for patients receiving multiple stents. Stent placement for benign tracheobronchial stenoses provides significant immediate improvement in airflow dynamics. Long-term improvement in airflow obstruction may be expected, and additional stent placements may further improve pulmonary function.

  11. Multi-Stage Admission Control for Load Balancing in Next Generation Systems

    DEFF Research Database (Denmark)

    Mihovska, Albena D.; Anggorojati, Bayu; Luo, Jijun

    2008-01-01

    This paper describes a load-dependent multi-stage admission control suitable for next generation systems. The concept uses decision polling in entities located at different levels of the architecture hierarchy and based on the load to activate a sequence of actions related to the admission...

  12. Generating description with multi-feature fusion and saliency maps of image

    Science.gov (United States)

    Liu, Lisha; Ding, Yuxuan; Tian, Chunna; Yuan, Bo

    2018-04-01

    Generating description for an image can be regard as visual understanding. It is across artificial intelligence, machine learning, natural language processing and many other areas. In this paper, we present a model that generates description for images based on RNN (recurrent neural network) with object attention and multi-feature of images. The deep recurrent neural networks have excellent performance in machine translation, so we use it to generate natural sentence description for images. The proposed method uses single CNN (convolution neural network) that is trained on ImageNet to extract image features. But we think it can not adequately contain the content in images, it may only focus on the object area of image. So we add scene information to image feature using CNN which is trained on Places205. Experiments show that model with multi-feature extracted by two CNNs perform better than which with a single feature. In addition, we make saliency weights on images to emphasize the salient objects in images. We evaluate our model on MSCOCO based on public metrics, and the results show that our model performs better than several state-of-the-art methods.

  13. Dynamic analyses, FPGA implementation and engineering applications of multi-butterfly chaotic attractors generated from generalised Sprott C system

    Science.gov (United States)

    Lai, Qiang; Zhao, Xiao-Wen; Rajagopal, Karthikeyan; Xu, Guanghui; Akgul, Akif; Guleryuz, Emre

    2018-01-01

    This paper considers the generation of multi-butterfly chaotic attractors from a generalised Sprott C system with multiple non-hyperbolic equilibria. The system is constructed by introducing an additional variable whose derivative has a switching function to the Sprott C system. It is numerically found that the system creates two-, three-, four-, five-butterfly attractors and any other multi-butterfly attractors. First, the dynamic analyses of multi-butterfly chaotic attractors are presented. Secondly, the field programmable gate array implementation, electronic circuit realisation and random number generator are done with the multi-butterfly chaotic attractors.

  14. Conducting a team-based multi-sited focused ethnography in primary care

    Directory of Open Access Journals (Sweden)

    A.P. Bikker

    2017-09-01

    Full Text Available Abstract Focused ethnography is an applied and pragmatic form of ethnography that explores a specific social phenomenon as it occurs in everyday life. Based on the literature a problem-focused research question is formulated before the data collection. The data generation process targets key informants and situations so that relevant results on the pre-defined topic can be obtained within a relatively short time-span. As part of a theory based evaluation of alternative forms of consultation (such as video, phone and email in primary care we used the focused ethnographic method in a multisite study in general practice across the UK. To date there is a gap in the literature on using focused ethnography in healthcare research. The aim of the paper is to build on the various methodological approaches in health services research by presenting the challenges and benefits we encountered whilst conducing a focused ethnography in British primary care. Our considerations are clustered under three headings: constructing a shared understanding, dividing the tasks within the team, and the functioning of the focused ethnographers within the broader multi-disciplinary team. As a result of using this approach we experienced several advantages, like the ability to collect focused data in several settings simultaneously within in a short time-span. Also, the sharing of experiences and interpretations between the researchers contributed to a more holistic understanding of the research topic. However, mechanisms need to be in place to facilitate and synthesise the observations, guide the analysis, and to ensure that all researchers feel engaged. Reflection, trust and flexibility among the team members were crucial to successfully adopt a team focused ethnographic approach. When used for policy focussed applied healthcare research a team-based multi-sited focused ethnography can uncover practices and understandings that would not be apparent through surveys or

  15. Conducting a team-based multi-sited focused ethnography in primary care.

    Science.gov (United States)

    Bikker, A P; Atherton, H; Brant, H; Porqueddu, T; Campbell, J L; Gibson, A; McKinstry, B; Salisbury, C; Ziebland, S

    2017-09-12

    Focused ethnography is an applied and pragmatic form of ethnography that explores a specific social phenomenon as it occurs in everyday life. Based on the literature a problem-focused research question is formulated before the data collection. The data generation process targets key informants and situations so that relevant results on the pre-defined topic can be obtained within a relatively short time-span. As part of a theory based evaluation of alternative forms of consultation (such as video, phone and email) in primary care we used the focused ethnographic method in a multisite study in general practice across the UK. To date there is a gap in the literature on using focused ethnography in healthcare research.The aim of the paper is to build on the various methodological approaches in health services research by presenting the challenges and benefits we encountered whilst conducing a focused ethnography in British primary care. Our considerations are clustered under three headings: constructing a shared understanding, dividing the tasks within the team, and the functioning of the focused ethnographers within the broader multi-disciplinary team.As a result of using this approach we experienced several advantages, like the ability to collect focused data in several settings simultaneously within in a short time-span. Also, the sharing of experiences and interpretations between the researchers contributed to a more holistic understanding of the research topic. However, mechanisms need to be in place to facilitate and synthesise the observations, guide the analysis, and to ensure that all researchers feel engaged. Reflection, trust and flexibility among the team members were crucial to successfully adopt a team focused ethnographic approach. When used for policy focussed applied healthcare research a team-based multi-sited focused ethnography can uncover practices and understandings that would not be apparent through surveys or interviews alone. If conducted with

  16. Optimization of multi-color laser waveform for high-order harmonic generation

    Science.gov (United States)

    Jin, Cheng; Lin, C. D.

    2016-09-01

    With the development of laser technologies, multi-color light-field synthesis with complete amplitude and phase control would make it possible to generate arbitrary optical waveforms. A practical optimization algorithm is needed to generate such a waveform in order to control strong-field processes. We review some recent theoretical works of the optimization of amplitudes and phases of multi-color lasers to modify the single-atom high-order harmonic generation based on genetic algorithm. By choosing different fitness criteria, we demonstrate that: (i) harmonic yields can be enhanced by 10 to 100 times, (ii) harmonic cutoff energy can be substantially extended, (iii) specific harmonic orders can be selectively enhanced, and (iv) single attosecond pulses can be efficiently generated. The possibility of optimizing macroscopic conditions for the improved phase matching and low divergence of high harmonics is also discussed. The waveform control and optimization are expected to be new drivers for the next wave of breakthrough in the strong-field physics in the coming years. Project supported by the Fundamental Research Funds for the Central Universities of China (Grant No. 30916011207), Chemical Sciences, Geosciences and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U. S. Department of Energy (Grant No. DE-FG02-86ER13491), and Air Force Office of Scientific Research, USA (Grant No. FA9550-14-1-0255).

  17. Effect of nanoparticles generation method on ionic conductivity in Yttria stabilized zirconia

    International Nuclear Information System (INIS)

    Khare, J.; Joshi, M.P.; Kukreja, L.M.; Satapathy, S.

    2013-01-01

    Yttria stabilized zirconia nanoparticles were generated in pulsed and CW mode of laser operation using CO 2 laser based laser vaporization method. Impedance spectroscopic measurements were carried out in frequency range of 100 Hz - 1 MHz at various temperatures ranging from room temperature to 500 C. The deconvolution of grain and grain boundary contribution were obtained from impedance spectra by an equivalent circuit analysis. Grain and grain boundary ionic conductivity of pellet made from nanoparticles generated in pulsed mode was two orders of magnitude large in comparison to pellets made from nanoparticles generated in CW mode of laser operation. The difference in ionic conductivities of pellets made from nanoparticles generated in pulsed mode and CW mode were explained on the basis of defect associations in nanoparticles produced during nanoparticles generation. (author)

  18. Mixing in 3D Sparse Multi-Scale Grid Generated Turbulence

    Science.gov (United States)

    Usama, Syed; Kopec, Jacek; Tellez, Jackson; Kwiatkowski, Kamil; Redondo, Jose; Malik, Nadeem

    2017-04-01

    Flat 2D fractal grids are known to alter turbulence characteristics downstream of the grid as compared to the regular grids with the same blockage ratio and the same mass inflow rates [1]. This has excited interest in the turbulence community for possible exploitation for enhanced mixing and related applications. Recently, a new 3D multi-scale grid design has been proposed [2] such that each generation of length scale of turbulence grid elements is held in its own frame, the overall effect is a 3D co-planar arrangement of grid elements. This produces a 'sparse' grid system whereby each generation of grid elements produces a turbulent wake pattern that interacts with the other wake patterns downstream. A critical motivation here is that the effective blockage ratio in the 3D Sparse Grid Turbulence (3DSGT) design is significantly lower than in the flat 2D counterpart - typically the blockage ratio could be reduced from say 20% in 2D down to 4% in the 3DSGT. If this idea can be realized in practice, it could potentially greatly enhance the efficiency of turbulent mixing and transfer processes clearly having many possible applications. Work has begun on the 3DSGT experimentally using Surface Flow Image Velocimetry (SFIV) [3] at the European facility in the Max Planck Institute for Dynamics and Self-Organization located in Gottingen, Germany and also at the Technical University of Catalonia (UPC) in Spain, and numerically using Direct Numerical Simulation (DNS) at King Fahd University of Petroleum & Minerals (KFUPM) in Saudi Arabia and in University of Warsaw in Poland. DNS is the most useful method to compare the experimental results with, and we are studying different types of codes such as Imcompact3d, and OpenFoam. Many variables will eventually be investigated for optimal mixing conditions. For example, the number of scale generations, the spacing between frames, the size ratio of grid elements, inflow conditions, etc. We will report upon the first set of findings

  19. Literature search strategies for conducting knowledge-building and theory-generating qualitative systematic reviews.

    Science.gov (United States)

    Finfgeld-Connett, Deborah; Johnson, E Diane

    2013-01-01

    To report literature search strategies for the purpose of conducting knowledge-building and theory-generating qualitative systematic reviews. Qualitative systematic reviews lie on a continuum from knowledge-building and theory-generating to aggregating and summarizing. Different types of literature searches are needed to optimally support these dissimilar reviews. Articles published between 1989-Autumn 2011. These documents were identified using a hermeneutic approach and multiple literature search strategies. Redundancy is not the sole measure of validity when conducting knowledge-building and theory-generating systematic reviews. When conducting these types of reviews, literature searches should be consistent with the goal of fully explicating concepts and the interrelationships among them. To accomplish this objective, a 'berry picking' approach is recommended along with strategies for overcoming barriers to finding qualitative research reports. To enhance integrity of knowledge-building and theory-generating systematic reviews, reviewers are urged to make literature search processes as transparent as possible, despite their complexity. This includes fully explaining and rationalizing what databases were used and how they were searched. It also means describing how literature tracking was conducted and grey literature was searched. In the end, the decision to cease searching also needs to be fully explained and rationalized. Predetermined linear search strategies are unlikely to generate search results that are adequate for purposes of conducting knowledge-building and theory-generating qualitative systematic reviews. Instead, it is recommended that iterative search strategies take shape as reviews evolve. © 2012 Blackwell Publishing Ltd.

  20. On-electrode autonomous current generator for multi-frequency EIT

    International Nuclear Information System (INIS)

    Jivet, I; Dragoi, B

    2008-01-01

    The paper presents an autonomous programmable current generator module for multi-frequency EIT systems. The module incorporates all stages from the sine wave generation with frequency and amplitude tuning, D/A converter and filter, a high output resistance voltage-to-current converter to the associated digital communication and control. The paper presents in depth the original digital quadrature signal generator and the output current generator with a high resistance. The other main blocks of the design use current practice specifications, since recent technological solutions proposed in the literature were found appropriate. The proposed signal generator circuit, characterized by a very low complexity, is analyzed in its capacity to produce multiple accurate signals up to 1 MHz in frequency. The precision output current source uses a modified current conveyor of type CCII with a high output resistance and low distortion. The output current frequency spectrum and linearity parameters obtained in the simulations are also described. The simulation results indicate a good linearity and high output resistance with an acceptable output voltage swing. The calculated performance parameters are validated with simulations, and future work for the prototype fabrication of the IC is outlined

  1. Chronic intersticial lung disease in the horse- Findings in arterial bloodgas analysis, tracheobronchial mucus cytology and radiological examination of the thorax; Chronisch interstitielle Lungenerkrankung beim Pferd - Blutgasanalytische, sekretzytolytische und röntgenologische Befunde

    Energy Technology Data Exchange (ETDEWEB)

    Dieckmann, M. [Klinik fuer Pferde, Tieraerztliche Hochschule Hannover (Germany); Klein, H. J.; Deegen, E.

    1990-07-01

    In 12 horses chronic interstitial lung disease was diagnosed. All horses were referrred because of unexplained loss of performance. In general there was no history of respiratory problems; 4 horses showed nasal discharge and 2 horses coughed. Results of arterial bloodgas analysis, tracheobronchial mucus cytology and radiological examination of the lungs were found in a typical combination, and they were different from results found generally in horses suffering from chronic obstructive pulmonary disease. Mean value of arterial partial pressure of oxygen was 100,6 mm Hg, arterial partial pressure of carbon dioxide was 45,1 mm Hg and alveolo-arterial difference in oxygen 5,1 mm Hg, respectively. In tracheobronchial aspirates pulmonary alveolar macrophages and neutrophil granulocytes were found in a relation of 2,6 : 1. Chest radiographs of all horses showed diffuse interstitial pattern throughout the lung.

  2. Graphene Transparent Conductive Electrodes for Next- Generation Microshutter Arrays

    Science.gov (United States)

    Li, Mary; Sultana, Mahmooda; Hess, Larry

    2012-01-01

    Graphene is a single atomic layer of graphite. It is optically transparent and has high electron mobility, and thus has great potential to make transparent conductive electrodes. This invention contributes towards the development of graphene transparent conductive electrodes for next-generation microshutter arrays. The original design for the electrodes of the next generation of microshutters uses indium-tin-oxide (ITO) as the electrode material. ITO is widely used in NASA flight missions. The optical transparency of ITO is limited, and the material is brittle. Also, ITO has been getting more expensive in recent years. The objective of the invention is to develop a graphene transparent conductive electrode that will replace ITO. An exfoliation procedure was developed to make graphene out of graphite crystals. In addition, large areas of single-layer graphene were produced using low-pressure chemical vapor deposition (LPCVD) with high optical transparency. A special graphene transport procedure was developed for transferring graphene from copper substrates to arbitrary substrates. The concept is to grow large-size graphene sheets using the LPCVD system through chemical reaction, transfer the graphene film to a substrate, dope graphene to reduce the sheet resistance, and pattern the film to the dimension of the electrodes in the microshutter array. Graphene transparent conductive electrodes are expected to have a transparency of 97.7%. This covers the electromagnetic spectrum from UV to IR. In comparison, ITO electrodes currently used in microshutter arrays have 85% transparency in mid-IR, and suffer from dramatic transparency drop at a wavelength of near-IR or shorter. Thus, graphene also has potential application as transparent conductive electrodes for Schottky photodiodes in the UV region.

  3. Fabrication of high conductivity dual multi-porous poly (L-lactic acid)/polypyrrole composite micro/nanofiber film

    International Nuclear Information System (INIS)

    Yu Qiaozhen; Dai Zhengwei; Lan Ping

    2011-01-01

    Highlights: → PLLA/H 2 SO 4 -doped PPy composite micro/nano fibers dual multi-pore membranes with high conductivity were fabricated by combining electrospinning with in situ polymerization.These composite fibers have a core-shell structure, the PPy is the core and the PLLA/PPy is the shell. → The size and shape of the pores in this PPy composite fiber membrane can be tuned by polymerization parameters. The largest size of the pores is about 250 μm. → The conductivity of this composite fiber membrane can be adjusted by polymerization parameters. The highest conductivity is 179.0 S cm -1 . The PLLA fibers act as the template in the pyrrole polymerization process and contributed to the increase of the conductivity. - Abstract: Dual multi-porous PLLA (poly(L-lactic acid))/H 2 SO 4 -doped PPy (polypyrrole) composite micro/nano fiber films were fabricated by combining electrospinning with in situ polymerization. The morphologies and structures of the resulting samples were analyzed by scanning electron microscopy (SEM). It was found that the composite micro/nano fibers exhibited a core-shell structure and the composite fiber film had a dual multi-pore structure composed of pores both in the fibers and among the fibers. Semiconductor parameter analyzer was used to characterize the electrical properties of the samples. It was interesting to find that all the PLLA/H 2 SO 4 -doped PPy composite micro/nano fiber films had higher conductivity than H 2 SO 4 -doped PPy particles when the polymerization time up to 180 min. Effects of the pyrrole synthesis conditions on the pore size and the conductivity of PLLA/PPy composite fiber film were assessed. By optimizing the polymerization conditions, the max conductivity of this composite fiber film was about 179.0 S cm -1 with a pore size of about 250 μm. The possible mechanism of PLLA/H 2 SO 4 -doped PPy composite micro/nano fiber films had much higher conductivity than H 2 SO 4 -doped PPy particles was discussed.

  4. A priori data-driven multi-clustered reservoir generation algorithm for echo state network.

    Directory of Open Access Journals (Sweden)

    Xiumin Li

    Full Text Available Echo state networks (ESNs with multi-clustered reservoir topology perform better in reservoir computing and robustness than those with random reservoir topology. However, these ESNs have a complex reservoir topology, which leads to difficulties in reservoir generation. This study focuses on the reservoir generation problem when ESN is used in environments with sufficient priori data available. Accordingly, a priori data-driven multi-cluster reservoir generation algorithm is proposed. The priori data in the proposed algorithm are used to evaluate reservoirs by calculating the precision and standard deviation of ESNs. The reservoirs are produced using the clustering method; only the reservoir with a better evaluation performance takes the place of a previous one. The final reservoir is obtained when its evaluation score reaches the preset requirement. The prediction experiment results obtained using the Mackey-Glass chaotic time series show that the proposed reservoir generation algorithm provides ESNs with extra prediction precision and increases the structure complexity of the network. Further experiments also reveal the appropriate values of the number of clusters and time window size to obtain optimal performance. The information entropy of the reservoir reaches the maximum when ESN gains the greatest precision.

  5. Surface-sensitive conductivity measurement using a micro multi-point probe approach

    DEFF Research Database (Denmark)

    Perkins, Edward; Barreto, Lucas; Wells, Justin

    2013-01-01

    An instrument for microscale electrical transport measurements in ultra-high vacuum is presented. The setup is constructed around collinear lithographically-created multi-point probes with a contact spacing down to 500 nm. Most commonly, twelve-point probes are used. These probes are approached...... measurements with an equidistant four-point probe for a wide range of contact spacings. In this way, it is possible to distinguish between bulk-like and surface-like conduction. The paper describes the design of the instrument and the approach to data and error analysis. Application examples are given...

  6. Multi-Objective Reservoir Optimization Balancing Energy Generation and Firm Power

    Directory of Open Access Journals (Sweden)

    Fang-Fang Li

    2015-07-01

    Full Text Available To maximize annual power generation and to improve firm power are important but competing goals for hydropower stations. The firm power output is decisive for the installed capacity in design, and represents the reliability of the power generation when the power plant is put into operation. To improve the firm power, the whole generation process needs to be as stable as possible, while the maximization of power generation requires a rapid rise of the water level at the beginning of the storage period. Taking the minimal power output as the firm power, both the total amount and the reliability of the hydropower generation are considered simultaneously in this study. A multi-objective model to improve the comprehensive benefits of hydropower stations are established, which is optimized by Non-dominated Sorting Genetic Algorithm-II (NSGA-II. The Three Gorges Cascade Hydropower System (TGCHS is taken as the study case, and the Pareto Fronts in different search spaces are obtained. The results not only prove the effectiveness of the proposed method, but also provide operational references for the TGCHS, indicating that there is room of improvement for both the annual power generation and the firm power.

  7. Coordinated Multi-Objective Control of Regulating Resources in Multi-Area Power Systems with Large Penetration of Wind Power Generation

    DEFF Research Database (Denmark)

    Nyeng, Preben; Yang, Bo; Ma, Jian

    2008-01-01

    This paper describes a control algorithm for a Wide Area Energy Storage and Management System (WAEMS). The WAEMS is designed to meet the demand for fast, accurate and reliable regulation services in multi-area power systems with a significant share of wind power and other intermittent generation...

  8. Multi-objective generation scheduling with hybrid energy resources

    Science.gov (United States)

    Trivedi, Manas

    In economic dispatch (ED) of electric power generation, the committed generating units are scheduled to meet the load demand at minimum operating cost with satisfying all unit and system equality and inequality constraints. Generation of electricity from the fossil fuel releases several contaminants into the atmosphere. So the economic dispatch objective can no longer be considered alone due to the environmental concerns that arise from the emissions produced by fossil fueled electric power plants. This research is proposing the concept of environmental/economic generation scheduling with traditional and renewable energy sources. Environmental/economic dispatch (EED) is a multi-objective problem with conflicting objectives since emission minimization is conflicting with fuel cost minimization. Production and consumption of fossil fuel and nuclear energy are closely related to environmental degradation. This causes negative effects to human health and the quality of life. Depletion of the fossil fuel resources will also be challenging for the presently employed energy systems to cope with future energy requirements. On the other hand, renewable energy sources such as hydro and wind are abundant, inexhaustible and widely available. These sources use native resources and have the capacity to meet the present and the future energy demands of the world with almost nil emissions of air pollutants and greenhouse gases. The costs of fossil fuel and renewable energy are also heading in opposite directions. The economic policies needed to support the widespread and sustainable markets for renewable energy sources are rapidly evolving. The contribution of this research centers on solving the economic dispatch problem of a system with hybrid energy resources under environmental restrictions. It suggests an effective solution of renewable energy to the existing fossil fueled and nuclear electric utilities for the cheaper and cleaner production of electricity with hourly

  9. Electrical conductivity of compacts of graphene, multi-wall carbon nanotubes, carbon black, and graphite powder

    NARCIS (Netherlands)

    Marinho, B.; Gomes Ghislandi, M.; Tkalya, E.; Koning, C.E.; With, de G.

    2012-01-01

    The electrical conductivity of different carbon materials (multi-walled carbon nanotubes, graphene, carbon black and graphite), widely used as fillers in polymeric matrices, was studied using compacts produced by a paper preparation process and by powder compression. Powder pressing assays show that

  10. 76 FR 55060 - Aquatic Ecosystems, Water Quality, and Global Change: Challenges of Conducting Multi-Stressor...

    Science.gov (United States)

    2011-09-06

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9459-7] Aquatic Ecosystems, Water Quality, and Global Change... entitled, Aquatic Ecosystems, Water Quality, and Global Change: Challenges of Conducting Multi- stressor... vulnerability of water quality and aquatic ecosystems across the United States to the potential impacts of...

  11. Multi-Functional Distributed Generation Unit for Power Quality Enhancement

    DEFF Research Database (Denmark)

    Zeng, Zheng; Yang, Huan; Guerrero, Josep M.

    2015-01-01

    A multi-functional distributed generation unit (MFDGU) and its control strategy are proposed in this paper for the purpose of enhancing power quality in low-voltage networks. By using the 3H-bridge converter structure, an MFDGU can be applied in 3-phase 4-wire low-voltage distribution networks...... reference of the MFDGU, which can be easily implemented in three-phase networks. A 15kVA prototype consisting of three full bridge converters has been built and tested. Experimental results show the feasibility of the proposed topology and control strategy....

  12. Simultaneous reconstruction of permittivity and conductivity using multi-frequency admittance measurement in electrical capacitance tomography

    International Nuclear Information System (INIS)

    Zhang, Maomao; Soleimani, Manuchehr

    2016-01-01

    Electrical capacitance tomography (ECT) is an imaging method mainly capable of reconstructing dielectric permittivity. Generally, the reactance part of complex admittance is measured in a selected frequency. This paper presents for the first time an in depth and systematic analysis of complex admittance data for simultaneous reconstruction of both electrical conductivity and dielectric permittivity. A complex-valued forward model, Jacobian matrix and inverse solution are developed in the time harmonic excitation mode to allow for multi-frequency measurements. Realistic noise models are used to evaluate the performance of complex admittance ECT in a range of excitation frequencies. This paper demonstrates far greater potential for ECT as a versatile imaging tool through novel analysis of complex admittance imaging using a dual conductivity permittivity inversion method. The paper demonstrates that various classes of contactless capacitance based measurement devices can be analysed through complex multi-frequency ECT. (paper)

  13. Elevation of susceptibility to ozone-induced acute tracheobronchial injury in transgenic mice deficient in Clara cell secretory protein

    International Nuclear Information System (INIS)

    Plopper, C.G.; Mango, G.W.; Hatch, G.E.; Wong, V.J.; Toskala, E.; Reynolds, S.D.; Tarkington, B.K.; Stripp, B.R.

    2006-01-01

    Increases in Clara cell abundance or cellular expression of Clara cell secretory protein (CCSP) may cause increased tolerance of the lung to acute oxidant injury by repeated exposure to ozone (O 3 ). This study defines how disruption of the gene for CCSP synthesis affects the susceptibility of tracheobronchial epithelium to acute oxidant injury. Mice homozygous for a null allele of the CCSP gene (CCSP-/-) and wild type (CCSP+/+) littermates were exposed to ozone (0.2 ppm, 8 h; 1 ppm, 8 h) or filtered air. Injury was evaluated by light and scanning electron microscopy, and the abundance of necrotic, ciliated, and nonciliated cells was estimated by morphometry. Proximal and midlevel intrapulmonary airways and terminal bronchioles were evaluated. There was no difference in airway epithelial composition between CCSP+/+ and CCSP-/- mice exposed to filtered air, and exposure to 0.2 ppm ozone caused little injury to the epithelium of both CCSP+/+ and CCSP-/- mice. After exposure to 1.0 ppm ozone, CCSP-/- mice suffered from a greater degree of epithelial injury throughout the airways compared to CCSP+/+ mice. CCSP-/- mice had both ciliated and nonciliated cell injury. Furthermore, lack of CCSP was associated with a shift in airway injury to include proximal airway generations. Therefore, we conclude that CCSP modulates the susceptibility of the epithelium to oxidant-induced injury. Whether this is due to the presence of CCSP on the acellular lining layer surface and/or its intracellular distribution in the secretory cell population needs to be defined

  14. Coordination between Generation and Transmission Maintenance Scheduling by Means of Multi-agent Technique

    Science.gov (United States)

    Nagata, Takeshi; Tao, Yasuhiro; Utatani, Masahiro; Sasaki, Hiroshi; Fujita, Hideki

    This paper proposes a multi-agent approach to maintenance scheduling in restructured power systems. The restructuring of electric power industry has resulted in market-based approaches for unbundling a multitude of service provided by self-interested entities such as power generating companies (GENCOs), transmission providers (TRANSCOs) and distribution companies (DISCOs). The Independent System Operator (ISO) is responsible for the security of the system operation. The schedule submitted to ISO by GENCOs and TRANSCOs should satisfy security and reliability constraints. The proposed method consists of several GENCO Agents (GAGs), TARNSCO Agents (TAGs) and a ISO Agent(IAG). The IAG’s role in maintenance scheduling is limited to ensuring that the submitted schedules do not cause transmission congestion or endanger the system reliability. From the simulation results, it can be seen the proposed multi-agent approach could coordinate between generation and transmission maintenance schedules.

  15. Generation of multi-branch beam with thermionic gun for the Japan linear collider

    International Nuclear Information System (INIS)

    Naito, T.; Akemoto, M.; Matsumonto, H.; Urakawa, J.; Yoshioka, M.; Akiyama, H.

    1992-01-01

    We report on the development of a thermionic gun that is capable of producing multi-bunch beam to be used at the KEK Accelerator Test Facility for the Japan Linear Collider project. Two types of grid pulse generators have been developed. One is an avalanche pulse generator. A Y-646E cathode was successfully operated to generate double-bunch beam with a pulse width shorter than 700 ps, bunch spacing 1.4 ns, and a peak current 4.3 A. The other grid pulse generator is a fast ECL circuit with an RF power amplifier. Generation of 20-pulse trains with 2.1 ns time spacing has been demonstrated. (Author) 4 refs., 6 figs

  16. Solutions for the conductivity of multi-coated spheres and spherically symmetric inclusion problems

    Science.gov (United States)

    Pham, Duc Chinh

    2018-02-01

    Variational results on the macroscopic conductivity (thermal, electrical, etc.) of the multi-coated sphere assemblage have been used to derive the explicit expression of the respective field (thermal, electrical, etc.) within the spheres in d dimensions (d=2,3). A differential substitution approach has been developed to construct various explicit expressions or determining equations for the effective spherically symmetric inclusion problems, which include those with radially variable conductivity, different radially variable transverse and normal conductivities, and those involving imperfect interfaces, in d dimensions. When the volume proportion of the outermost spherical shell increases toward 1, one obtains the respective exact results for the most important specific cases: the dilute solutions for the compound inhomogeneities suspended in a major matrix phase. Those dilute solution results are also needed for other effective medium approximation schemes.

  17. SPAGETTA: a Multi-Purpose Gridded Stochastic Weather Generator

    Science.gov (United States)

    Dubrovsky, M.; Huth, R.; Rotach, M. W.; Dabhi, H.

    2017-12-01

    SPAGETTA is a new multisite/gridded multivariate parametric stochastic weather generator (WG). Site-specific precipitation occurrence and amount are modelled by Markov chain and Gamma distribution, the non-precipitation variables are modelled by an autoregressive (AR) model conditioned on precipitation occurrence, and the spatial coherence of all variables is modelled following the Wilks' (2009) approach. SPAGETTA may be run in two modes. Mode 1: it is run as a classical WG, which is calibrated using weather series from multiple sites, and only then it may produce arbitrarily long synthetic series mimicking the spatial and temporal structure of the calibration data. To generate the weather series representing the future climate, the WG parameters are modified according to the climate change scenario, typically derived from GCM or RCM simulations. Mode 2: the user provides only basic information (not necessarily to be realistic) on the temporal and spatial auto-correlation structure of the weather variables and their mean annual cycle; the generator itself derives the parameters of the underlying AR model, which produces the multi-site weather series. Optionally, the user may add the spatially varying trend, which is superimposed to the synthetic series. The contribution consists of following parts: (a) Model of the WG. (b) Validation of WG in terms of the spatial temperature and precipitation characteristics, including characteristics of spatial hot/cold/dry/wet spells. (c) Results of the climate change impact experiment, in which the WG parameters representing the spatial and temporal variability are modified using the climate change scenarios and the effect on the above spatial validation indices is analysed. In this experiment, the WG is calibrated using the E-OBS gridded daily weather data for several European regions, and the climate change scenarios are derived from the selected RCM simulations (CORDEX database). (d) The second mode of operation will be

  18. A magnet built on bronchoscopic suction for extraction of tracheobronchial headscarf pins: a novel technique and review of a tertiary centre experience†

    Science.gov (United States)

    Elsayed, Hany H.; Mostafa, Ahmed M.; Soliman, Saleh; El-Bawab, Hatem Y.; Moharram, Adel A.; El-Nori, Ahmed A.

    2016-01-01

    OBJECTIVES Airway metal pins are one of the most commonly inhaled foreign bodies in Eastern societies in young females wearing headscarves. We innovated a modified bronchoscopic technique to extract tracheobronchial headscarf pins by the insertion of a magnet to allow an easy and non-traumatic extraction of the pins. The aim of this study was to assess the feasibility and safety of our new technique and compare it with our large previous experience with the classic bronchoscopic method of extraction of tracheobronchial headscarf pins. METHODS We performed a study comparing our retrospective experience of classic bronchoscopic extraction from February 2004 to January 2014 and prospective experience with our modified technique using the magnet from January 2014 to June 2015. An institutional review board and new device approval were obtained. RESULTS Three hundred and twenty-six procedures on 315 patients were performed during our initial 10-year experience. Of them, 304 patients were females. The median age of our group was 13 (0–62). The median time from inhalation to procedure was 1 day (0–1022). After introducing our modified new technique using the magnet, 20 procedures were performed. Nineteen were females. The median time of the procedure and the need to forcefully bend the pin for extraction were in favour of the new technique in comparison with our classic approach (2 vs 6 min; P magnets was safer and simpler in comparison with our large experience with the classic approach. We advise the use of this device (or concept) in selected patients in centres dealing with this problem. PMID:26850113

  19. Speed-sensorless control strategy for multi-phase induction generator in wind energy conversion systems

    Directory of Open Access Journals (Sweden)

    Dumnić Boris P.

    2016-01-01

    Full Text Available Renewable energy sources, especially wind energy conversion systems (WECS, exhibit constant growth. Increase in power and installed capacity led to advances in WECS topologies. Multi-phase approach presents a new development direction, with several key advantages over three-phase systems. Paired with a sensorless control strategy, multi-phase machines are expected to take primacy over standard solutions. This paper presents speed sensorless vector control of an asymmetrical six-phase induction generator based on a model reference adaptive system (MRAS. Suggested topology and developed control algorithm show that sensorless control can yield appropriate dynamic characteristics for the use in WECS with increase in reliability and robustness. [Projekat Ministarstva nauke Republike Srbije, br. III 042004: Smart Electricity Distribution Grids Based on Distribution Management System and Distributed Generation

  20. An Enhanced Multi-Pager Environment Support for Second Generation Microkernels

    OpenAIRE

    Klimiankou, Yauhen

    2014-01-01

    The main objective of this paper is to present a mechanism of enhanced paging support for the second generation microkernels in the form of explicit support of multi-pager environment for the tasks running in the system. Proposed mechanism is based on the intra-kernel high granularity pagers assignments per virtual address space, which allow efficient and simple dispatching of page faults to the appropriate pagers. The paging is one of the major features of the virtual memory, which is extens...

  1. Generating relations of multi-variable Tricomi functions of two indices using Lie algebra representation

    Directory of Open Access Journals (Sweden)

    Nader Ali Makboul Hassan

    2014-01-01

    Full Text Available This paper is an attempt to stress the usefulness of the multi-variable special functions. In this paper, we derive certain generating relations involving 2-indices 5-variables 5-parameters Tricomi functions (2I5V5PTF by using a Lie-algebraic method. Further, we derive certain new and known generating relations involving other forms of Tricomi and Bessel functions as applications.

  2. Rapid generation of control parameters of Multi-Infeed system through online simulation

    Directory of Open Access Journals (Sweden)

    Rasool Aazim

    2017-05-01

    Full Text Available Simulated Self-Generated - Particle Swarm optimization (SSG-PSO toolbox that automatically generates PI control parameters very quickly in PSCAD is designed. This toolbox operates by utilizing transient simulation to evaluate objective function and converges the fitness values of objective function through PSO algorithm during run time simulation of Multi-infeed HVDC systems. Integral Square Error-Objective Function (ISE-OF is used to accomplish the task. To make the toolbox faster, ranges are set for PSO generated value that limit the time of data acquisition for the objective function by only considering transition time of a system. This toolbox has a capability to optimize multiple controllers at same time. The PI values are generated faster and the results are showing markedly improved performance of a system during startup and under fault condition. The experimental results are presented in this paper.

  3. Multi-GeV electron-positron beam generation from laser-electron scattering.

    Science.gov (United States)

    Vranic, Marija; Klimo, Ondrej; Korn, Georg; Weber, Stefan

    2018-03-16

    The new generation of laser facilities is expected to deliver short (10 fs-100 fs) laser pulses with 10-100 PW of peak power. This opens an opportunity to study matter at extreme intensities in the laboratory and provides access to new physics. Here we propose to scatter GeV-class electron beams from laser-plasma accelerators with a multi-PW laser at normal incidence. In this configuration, one can both create and accelerate electron-positron pairs. The new particles are generated in the laser focus and gain relativistic momentum in the direction of laser propagation. Short focal length is an advantage, as it allows the particles to be ejected from the focal region with a net energy gain in vacuum. Electron-positron beams obtained in this setup have a low divergence, are quasi-neutral and spatially separated from the initial electron beam. The pairs attain multi-GeV energies which are not limited by the maximum energy of the initial electron beam. We present an analytical model for the expected energy cutoff, supported by 2D and 3D particle-in-cell simulations. The experimental implications, such as the sensitivity to temporal synchronisation and laser duration is assessed to provide guidance for the future experiments.

  4. Measurements of void fraction by an improved multi-channel conductance void meter

    International Nuclear Information System (INIS)

    Song, Chul-Hwa; Chung, Moon Ki; No, Hee Cheon

    1998-01-01

    An improved multi-channel Conductance Void Meter (CVM) was developed to measure a void fraction. Its measuring principle is basically based upon the differences of electrical conductance of a two-phase mixture due to the variation of void fraction around a sensor. The sensor is designed to be flush-mounted to the inner wall of the test section to avoid the flow disturbances. The signal processor with three channels is specially designed so as to minimize the inherent error due to the phase difference between channels. It is emphasized that the guard electrodes are electrically shielded in order not to affect the measurements of two-phase mixture conductance, but to make the electric fields evenly distributed in a measuring volume. Void fraction is measured for bubbly and slug flow regimes in a vertical air-water loop, and statistical signal processing techniques are applied to show that CVM has a good dynamic resolution which is required to investigate the structural developments of bubbly flow and the propagation of void waves in a flow channel. (author)

  5. Highly conductive, transparent flexible films based on open rings of multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Ko, Wen-Yin; Su, Jun-Wei; Guo, Chian-Hua; Fu, Shu-Juan; Hsu, Chuen-Yuan; Lin, Kuan-Jiuh

    2011-01-01

    Open rings of multi-walled carbon nanotubes were stacked to form porous networks on a poly(ethylene terephthalate) substrate to form a flexible conducting film (MWCNT-PET) with good electrical conductivity and transparency by a combination of ultrasonic atomization and spin-coating technique. To enhance the electric flexibility, we spin-coated a cast film of poly(vinyl alcohol) onto the MWCNT-PET substrate, which then underwent a thermo-compression process. Field-emission scanning electron microscopy of the cross-sectional morphology illustrates that the film has a robust network with a thickness of ∼ 175 nm, and it remarkably exhibits a sheet resistance of approximately 370 Ω/sq with ∼ 77% transmittance at 550 nm even after 500 bending cycles. This electrical conductivity is much superior to that of other MWCNT-based transparent flexible films.

  6. A magnet built on bronchoscopic suction for extraction of tracheobronchial headscarf pins: a novel technique and review of a tertiary centre experience.

    Science.gov (United States)

    Elsayed, Hany H; Mostafa, Ahmed M; Soliman, Saleh; El-Bawab, Hatem Y; Moharram, Adel A; El-Nori, Ahmed A

    2016-05-01

    Airway metal pins are one of the most commonly inhaled foreign bodies in Eastern societies in young females wearing headscarves. We innovated a modified bronchoscopic technique to extract tracheobronchial headscarf pins by the insertion of a magnet to allow an easy and non-traumatic extraction of the pins. The aim of this study was to assess the feasibility and safety of our new technique and compare it with our large previous experience with the classic bronchoscopic method of extraction of tracheobronchial headscarf pins. We performed a study comparing our retrospective experience of classic bronchoscopic extraction from February 2004 to January 2014 and prospective experience with our modified technique using the magnet from January 2014 to June 2015. An institutional review board and new device approval were obtained. Three hundred and twenty-six procedures on 315 patients were performed during our initial 10-year experience. Of them, 304 patients were females. The median age of our group was 13 (0-62). The median time from inhalation to procedure was 1 day (0-1022). After introducing our modified new technique using the magnet, 20 procedures were performed. Nineteen were females. The median time of the procedure and the need to forcefully bend the pin for extraction were in favour of the new technique in comparison with our classic approach (2 vs 6 min; P magnets was safer and simpler in comparison with our large experience with the classic approach. We advise the use of this device (or concept) in selected patients in centres dealing with this problem. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  7. Histologic findings in the tracheobronchial tree of uranium miners and non-miners with lung cancer

    International Nuclear Information System (INIS)

    Auerbach, O.; Saccomanno, G.; Kuschner, M.; Brown, R.D.; Garfinkel, L.

    1978-01-01

    The remaining tissue of the tracheobronchial tree from 210 men who died from lung cancer was studied to compare the histologic alterations leading to further sites of primary cancer. These men were uranium miners matched with nonminers for age and smoking habits. In the examination of a total of 28,928 cross-sections carcinoma in situ was found in 96 percent of the miners and in 92 percent of the nonminers. The number of slides from miners showing degree 2 or 3 atypia in areas of carcinoma in situ was about double the number found from the nonminers. Although the difference was not statistically significant, 32 percent of the miners had at least one section showing early primary invasive carcinoma compared with 22 percent of the nonminers. The data indicate that the synergistic effect of the exposure to uranium dust along with cigarette smoking increases the risk of lung cancer and that in addition to a main tumor mass, other sites of tissue alterations leading to tumor development are frequently already present in the lung

  8. Real-time Distributed Economic Dispatch forDistributed Generation Based on Multi-Agent System

    DEFF Research Database (Denmark)

    Luo, Kui; Wu, Qiuwei; Nielsen, Arne Hejde

    2015-01-01

    The distributed economic dispatch for distributed generation is formulated as a optimization problem with equality and inequality constraints. An effective distributed approach based on multi-agent system is proposed for solving the economic dispatch problem in this paper. The proposed approach...... consists of two stages. In the first stage, an adjacency average allocation algorithm is proposed to ensure the generation-demand equality. In the second stage, a local replicator dynamics algorithm is applied to achieve nash equilibrium for the power dispatch game. The approach is implemented in a fully...

  9. Fusion of space-borne multi-baseline and multi-frequency interferometric results based on extended Kalman filter to generate high quality DEMs

    Science.gov (United States)

    Zhang, Xiaojie; Zeng, Qiming; Jiao, Jian; Zhang, Jingfa

    2016-01-01

    Repeat-pass Interferometric Synthetic Aperture Radar (InSAR) is a technique that can be used to generate DEMs. But the accuracy of InSAR is greatly limited by geometrical distortions, atmospheric effect, and decorrelations, particularly in mountainous areas, such as western China where no high quality DEM has so far been accomplished. Since each of InSAR DEMs generated using data of different frequencies and baselines has their own advantages and disadvantages, it is therefore very potential to overcome some of the limitations of InSAR by fusing Multi-baseline and Multi-frequency Interferometric Results (MMIRs). This paper proposed a fusion method based on Extended Kalman Filter (EKF), which takes the InSAR-derived DEMs as states in prediction step and the flattened interferograms as observations in control step to generate the final fused DEM. Before the fusion, detection of layover and shadow regions, low-coherence regions and regions with large height error is carried out because MMIRs in these regions are believed to be unreliable and thereafter are excluded. The whole processing flow is tested with TerraSAR-X and Envisat ASAR datasets. Finally, the fused DEM is validated with ASTER GDEM and national standard DEM of China. The results demonstrate that the proposed method is effective even in low coherence areas.

  10. SmaggIce 2.0: Additional Capabilities for Interactive Grid Generation of Iced Airfoils

    Science.gov (United States)

    Kreeger, Richard E.; Baez, Marivell; Braun, Donald C.; Schilling, Herbert W.; Vickerman, Mary B.

    2008-01-01

    The Surface Modeling and Grid Generation for Iced Airfoils (SmaggIce) software toolkit has been extended to allow interactive grid generation for multi-element iced airfoils. The essential phases of an icing effects study include geometry preparation, block creation and grid generation. SmaggIce Version 2.0 now includes these main capabilities for both single and multi-element airfoils, plus an improved flow solver interface and a variety of additional tools to enhance the efficiency and accuracy of icing effects studies. An overview of these features is given, especially the new multi-element blocking strategy using the multiple wakes method. Examples are given which illustrate the capabilities of SmaggIce for conducting an icing effects study for both single and multi-element airfoils.

  11. Placement of tracheobronchial silicone Y-stents: Multicenter experience and systematic review of the literature

    Directory of Open Access Journals (Sweden)

    Inderpaul Singh Sehgal

    2017-01-01

    Full Text Available Background: Airway obstruction or tracheoesophageal fistula (TEF near the tracheal carina requires placement of Y-shaped stents. Herein, we describe our multicenter experience with the placement of Dumon silicone Y-stents. We also conduct a systematic review for studies describing the deployment of airway silicone Y-stents. Methods: This was a retrospective analysis of consecutive subjects who underwent placement of silicone Y-stents. The clinical details including the underlying diagnosis, indication for the placement of silicone Y-stents, success of stent placement, and follow-up are presented. The PubMed and EMBASE databases were also reviewed for studies describing the placement of silicone Y-stents. Results: During the study, 27 silicone Y-stents were placed. The mean (standard deviation age of the study population (85.2% males was 57.7 (13.5 years. The stents were placed for airway obstruction in 77.8% and TEF in 29.6% of the patients. The most common underlying disease was carcinoma of the esophagus. The degree of airway obstruction was grade 3–4 in 18 subjects, and respiratory failure was encountered in 18 subjects. The stent was deployed successfully in all the subjects. No deaths were encountered during stent placement. Most subjects had rapid relief of symptoms following the procedure. Excessive secretions and mucostasis were the most common stent-related complications followed by the development of granulation tissue. The systematic review yielded nine studies (338 subjects with airway obstruction and/or TEF. The most common indication for silicone Y-stent placement was tracheobronchial obstruction and TEF due to malignancy. Benign disorders that necessitated stent placement included postintubation tracheal stenosis, airway malacia, and others. The stent was successfully placed in 98% with only one periprocedural death. Granulation tissue formation and mucostasis were the most common stent-related complications. Conclusion

  12. Multi-relaxation-time lattice Boltzmann modeling of the acoustic field generated by focused transducer

    Science.gov (United States)

    Shan, Feng; Guo, Xiasheng; Tu, Juan; Cheng, Jianchun; Zhang, Dong

    The high-intensity focused ultrasound (HIFU) has become an attractive therapeutic tool for the noninvasive tumor treatment. The ultrasonic transducer is the key component in HIFU treatment to generate the HIFU energy. The dimension of focal region generated by the transducer is closely relevant to the safety of HIFU treatment. Therefore, it is essential to numerically investigate the focal region of the transducer. Although the conventional acoustic wave equations have been used successfully to describe the acoustic field, there still exist some inherent drawbacks. In this work, we presented an axisymmetric isothermal multi-relaxation-time lattice Boltzmann method (MRT-LBM) model with the Bouzidi-Firdaouss-Lallemand (BFL) boundary condition in cylindrical coordinate system. With this model, some preliminary simulations were firstly conducted to determine a reasonable value of the relaxation parameter. Then, the validity of the model was examined by comparing the results obtained with the LBM results with the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation and the Spheroidal beam equation (SBE) for the focused transducers with different aperture angles, respectively. In addition, the influences of the aperture angle on the focal region were investigated. The proposed model in this work will provide significant references for the parameter optimization of the focused transducer for applications in the HIFU treatment or other fields, and provide new insights into the conventional acoustic numerical simulations.

  13. Development and Analysis of Volume Multi-Sphere Method Model Generation using Electric Field Fitting

    Science.gov (United States)

    Ingram, G. J.

    Electrostatic modeling of spacecraft has wide-reaching applications such as detumbling space debris in the Geosynchronous Earth Orbit regime before docking, servicing and tugging space debris to graveyard orbits, and Lorentz augmented orbits. The viability of electrostatic actuation control applications relies on faster-than-realtime characterization of the electrostatic interaction. The Volume Multi-Sphere Method (VMSM) seeks the optimal placement and radii of a small number of equipotential spheres to accurately model the electrostatic force and torque on a conducting space object. Current VMSM models tuned using force and torque comparisons with commercially available finite element software are subject to the modeled probe size and numerical errors of the software. This work first investigates fitting of VMSM models to Surface-MSM (SMSM) generated electrical field data, removing modeling dependence on probe geometry while significantly increasing performance and speed. A proposed electric field matching cost function is compared to a force and torque cost function, the inclusion of a self-capacitance constraint is explored and 4 degree-of-freedom VMSM models generated using electric field matching are investigated. The resulting E-field based VMSM development framework is illustrated on a box-shaped hub with a single solar panel, and convergence properties of select models are qualitatively analyzed. Despite the complex non-symmetric spacecraft geometry, elegantly simple 2-sphere VMSM solutions provide force and torque fits within a few percent.

  14. "Martin Luther King Stopped Discrimination": Multi-Generational Latino Elementary Students' Perceptions of Social Issues

    Science.gov (United States)

    Curwen, Margie Sauceda

    2011-01-01

    This study explored how multi-generational, middle-class, fifth-graders from Latino families responded to classroom discussions of social issues--particularly discrimination--and draws upon sociocultural views of culture, educational theory, and sociological perspectives of immigration to provide insight into the learning experiences of one group…

  15. Removal of metallic tracheobronchial stents in lung transplantation with flexible bronchoscopy

    Directory of Open Access Journals (Sweden)

    Fruchter Oren

    2010-09-01

    Full Text Available Abstract Background Airway complications are among the most challenging problems after lung transplantation, and Self-Expandable Metallic Stents (SEMS are used to treat airway complications such as stenosis or malacia at the bronchial anastomosis sites. Several transplantation centers are reluctant to use SEMS since their removal is sometimes needed and usually requires the use of rigid bronchoscopy under general anesthesia. The objective of the current report is to describe our experience in SEMS retrieval by flexible bronchoscopy under conscious sedation. Methods A retrospective review was done of patients requiring tracheobronchial stent placement after lung transplantation in which the SEMS had to be removed. The retrieval procedure was done by flexible bronchoscopy on a day-care ambulatory basis. Results Between January 2004 and January 2010, out of 305 lung transplantation patients, 24 (7.8% underwent SEMS placement. Indications included bronchial stenosis in 20 and bronchomalacia in 4. In six patients (25% the SEMS had to be removed due to excessive granulation tissue formation and stent obstruction. The average time from SEMS placement to retrieval was 30 months (range 16-48 months. The stent was completely removed in five patients and partially removed in one patient; no major complications were encountered, and all patients were discharged within 3 hours of the procedure. In all procedures, new SEMS was successfully re-inserted thereafter. Conclusions The retrieval of SEMS in patients that underwent lung transplantation can be effectively and safely done under conscious sedation using flexible bronchoscopy on a day-care basis, this observation should encourage increasing usage of SEMS in highly selected patients.

  16. Optimal power system generation scheduling by multi-objective genetic algorithms with preferences

    International Nuclear Information System (INIS)

    Zio, E.; Baraldi, P.; Pedroni, N.

    2009-01-01

    Power system generation scheduling is an important issue both from the economical and environmental safety viewpoints. The scheduling involves decisions with regards to the units start-up and shut-down times and to the assignment of the load demands to the committed generating units for minimizing the system operation costs and the emission of atmospheric pollutants. As many other real-world engineering problems, power system generation scheduling involves multiple, conflicting optimization criteria for which there exists no single best solution with respect to all criteria considered. Multi-objective optimization algorithms, based on the principle of Pareto optimality, can then be designed to search for the set of nondominated scheduling solutions from which the decision-maker (DM) must a posteriori choose the preferred alternative. On the other hand, often, information is available a priori regarding the preference values of the DM with respect to the objectives. When possible, it is important to exploit this information during the search so as to focus it on the region of preference of the Pareto-optimal set. In this paper, ways are explored to use this preference information for driving a multi-objective genetic algorithm towards the preferential region of the Pareto-optimal front. Two methods are considered: the first one extends the concept of Pareto dominance by biasing the chromosome replacement step of the algorithm by means of numerical weights that express the DM' s preferences; the second one drives the search algorithm by changing the shape of the dominance region according to linear trade-off functions specified by the DM. The effectiveness of the proposed approaches is first compared on a case study of literature. Then, a nonlinear, constrained, two-objective power generation scheduling problem is effectively tackled

  17. Sustainability assessment of electricity generation technologies using weighted multi-criteria decision analysis

    International Nuclear Information System (INIS)

    Maxim, Alexandru

    2014-01-01

    Solving the issue of environmental degradation due to the expansion of the World's energy demand requires a balanced approach. The aim of this paper is to comprehensively rank a large number of electricity generation technologies based on their compatibility with the sustainable development of the industry. The study is based on a set of 10 sustainability indicators which provide a life cycle analysis of the plants. The technologies are ranked using a weighted sum multi-attribute utility method. The indicator weights were established through a survey of 62 academics from the fields of energy and environmental science. Our results show that large hydroelectric projects are the most sustainable technology type, followed by small hydro, onshore wind and solar photovoltaic. We argue that political leaders should have a more structured and strategic approach in implementing sustainable energy policies and this type of research can provide arguments to support such decisions. - Highlights: • We rank 13 electricity generation technologies based on sustainability. • We use 10 indicators in a weighted sum multi-attribute utility approach. • Weights are calculated based on a survey of 62 academics from the field. • Large hydroelectric projects are ranked as the most sustainable. • Decision makers can use the results to promote a more sustainable energy industry

  18. Multi-Objective Planning of Multi-Type Distributed Generation Considering Timing Characteristics and Environmental Benefits

    Directory of Open Access Journals (Sweden)

    Yajing Gao

    2014-09-01

    Full Text Available This paper presents a novel approach to multi-type distributed generation (DG planning based on the analysis of investment and income brought by grid-connected DG. Firstly, the timing characteristics of loads and DG outputs, as well as the environmental benefits of DG are analyzed. Then, on the basis of the classification of daily load sequences, the typical daily load sequence and the typical daily output sequence of DG per unit capacity can be computed. The proposed planning model takes the location, capacity and types of DG into account as optimization variables. An improved adaptive genetic algorithm is proposed to solve the model. Case studies have been carried out on the IEEE 14-node distribution system to verify the feasibility and effectiveness of the proposed method and model.

  19. Optimal generation and reserve dispatch in a multi-area competitive market using a hybrid direct search method

    International Nuclear Information System (INIS)

    Chun Lung Chen

    2005-01-01

    With restructuring of the power industry, competitive bidding for energy and ancillary services are increasingly recognized as an important part of electricity markets. It is desirable to optimize not only the generator's bid prices for energy and for providing minimized ancillary services but also the transmission congestion costs. In this paper, a hybrid approach of combining sequential dispatch with a direct search method is developed to deal with the multi-product and multi-area electricity market dispatch problem. The hybrid direct search method (HDSM) incorporates sequential dispatch into the direct search method to facilitate economic sharing of generation and reserve across areas and to minimize the total market cost in a multi-area competitive electricity market. The effects of tie line congestion and area spinning reserve requirement are also consistently reflected in the marginal price in each area. Numerical experiments are included to understand the various constraints in the market cost analysis and to provide valuable information for market participants in a pool oriented electricity market. (author)

  20. Optimal generation and reserve dispatch in a multi-area competitive market using a hybrid direct search method

    International Nuclear Information System (INIS)

    Chen, C.-L.

    2005-01-01

    With restructuring of the power industry, competitive bidding for energy and ancillary services are increasingly recognized as an important part of electricity markets. It is desirable to optimize not only the generator's bid prices for energy and for providing minimized ancillary services but also the transmission congestion costs. In this paper, a hybrid approach of combining sequential dispatch with a direct search method is developed to deal with the multi-product and multi-area electricity market dispatch problem. The hybrid direct search method (HDSM) incorporates sequential dispatch into the direct search method to facilitate economic sharing of generation and reserve across areas and to minimize the total market cost in a multi-area competitive electricity market. The effects of tie line congestion and area spinning reserve requirement are also consistently reflected in the marginal price in each area. Numerical experiments are included to understand the various constraints in the market cost analysis and to provide valuable information for market participants in a pool oriented electricity market

  1. A generative modeling approach to connectivity-Electrical conduction in vascular networks

    DEFF Research Database (Denmark)

    Hald, Bjørn Olav

    2016-01-01

    The physiology of biological structures is inherently dynamic and emerges from the interaction and assembly of large collections of small entities. The extent of coupled entities complicates modeling and increases computational load. Here, microvascular networks are used to present a novel...... to synchronize vessel tone across the vast distances within a network. We hypothesize that electrical conduction capacity is delimited by the size of vascular structures and connectivity of the network. Generation and simulation of series of dynamical models of electrical spread within vascular networks...... of different size and composition showed that (1) Conduction is enhanced in models harboring long and thin endothelial cells that couple preferentially along the longitudinal axis. (2) Conduction across a branch point depends on endothelial connectivity between branches. (3) Low connectivity sub...

  2. Transnasal tracheobronchial stenting for malignant airway narrowing under local anesthesia: Our experience of treating three cases using this technique

    International Nuclear Information System (INIS)

    Medhi, Jayanta; Handique, Akash; Goyal, Amit; Lynser, Donbok; Phukan, Pranjal; Sarma, Kalyan; Padmanabhan, Aswin; Saikia, Manuj Kumar; Chutia, Happy

    2016-01-01

    To study the technical feasibility of tracheobronchial stenting via transnasal route under bronchoscopy and fluoroscopic guidance in severe malignant airway strictures using self-expandable nitinol stents. We describe three patients with malignant airway strictures, treated entirely via transnasal route under local anesthesia using bronchoscopic and fluoroscopic guidance. Nasal route allowed convenient access to the airway for the bronchoscope across the stricture and a guidewire was introduced through its working channel. The 18F tracheal stent and the 6F bronchial stent assembly could be easily introduced and deployed under bronchoscopic (reintroduced through the other nostril) and fluoroscopic guidance. We achieved technical success in all the three patients with immediate relief of dyspnea. Transnasal airway stenting with self-expandable nitinol stent using bronchoscopic and fluoroscopic guidance under local anesthesia is a safe and effective method with minimal patient discomfort

  3. Development of Multi-Scale Finite Element Analysis Codes for High Formability Sheet Metal Generation

    International Nuclear Information System (INIS)

    Nnakamachi, Eiji; Kuramae, Hiroyuki; Ngoc Tam, Nguyen; Nakamura, Yasunori; Sakamoto, Hidetoshi; Morimoto, Hideo

    2007-01-01

    In this study, the dynamic- and static-explicit multi-scale finite element (F.E.) codes are developed by employing the homogenization method, the crystalplasticity constitutive equation and SEM-EBSD measurement based polycrystal model. These can predict the crystal morphological change and the hardening evolution at the micro level, and the macroscopic plastic anisotropy evolution. These codes are applied to analyze the asymmetrical rolling process, which is introduced to control the crystal texture of the sheet metal for generating a high formability sheet metal. These codes can predict the yield surface and the sheet formability by analyzing the strain path dependent yield, the simple sheet forming process, such as the limit dome height test and the cylindrical deep drawing problems. It shows that the shear dominant rolling process, such as the asymmetric rolling, generates ''high formability'' textures and eventually the high formability sheet. The texture evolution and the high formability of the newly generated sheet metal experimentally were confirmed by the SEM-EBSD measurement and LDH test. It is concluded that these explicit type crystallographic homogenized multi-scale F.E. code could be a comprehensive tool to predict the plastic induced texture evolution, anisotropy and formability by the rolling process and the limit dome height test analyses

  4. Generation of a landslide risk index map for Cuba using spatial multi-criteria evaluation

    NARCIS (Netherlands)

    Castellanos Abella, E.A.

    2007-01-01

    his paper explains the procedure for the generation of a landslide risk index map at national level in Cuba, using a semiquantitative model with ten indicator maps and a cell size of 90× 90 m. The model was designed and implemented using spatial multi-criteria evaluation techniques in a GIS system.

  5. An Adaptive Model Predictive Load Frequency Control Method for Multi-Area Interconnected Power Systems with Photovoltaic Generations

    Directory of Open Access Journals (Sweden)

    Guo-Qiang Zeng

    2017-11-01

    Full Text Available As the penetration level of renewable distributed generations such as wind turbine generator and photovoltaic stations increases, the load frequency control issue of a multi-area interconnected power system becomes more challenging. This paper presents an adaptive model predictive load frequency control method for a multi-area interconnected power system with photovoltaic generation by considering some nonlinear features such as a dead band for governor and generation rate constraint for steam turbine. The dynamic characteristic of this system is formulated as a discrete-time state space model firstly. Then, the predictive dynamic model is obtained by introducing an expanded state vector, and rolling optimization of control signal is implemented based on a cost function by minimizing the weighted sum of square predicted errors and square future control values. The simulation results on a typical two-area power system consisting of photovoltaic and thermal generator have demonstrated the superiority of the proposed model predictive control method to these state-of-the-art control techniques such as firefly algorithm, genetic algorithm, and population extremal optimization-based proportional-integral control methods in cases of normal conditions, load disturbance and parameters uncertainty.

  6. A conditional stochastic weather generator for seasonal to multi-decadal simulations

    Science.gov (United States)

    Verdin, Andrew; Rajagopalan, Balaji; Kleiber, William; Podestá, Guillermo; Bert, Federico

    2018-01-01

    We present the application of a parametric stochastic weather generator within a nonstationary context, enabling simulations of weather sequences conditioned on interannual and multi-decadal trends. The generalized linear model framework of the weather generator allows any number of covariates to be included, such as large-scale climate indices, local climate information, seasonal precipitation and temperature, among others. Here we focus on the Salado A basin of the Argentine Pampas as a case study, but the methodology is portable to any region. We include domain-averaged (e.g., areal) seasonal total precipitation and mean maximum and minimum temperatures as covariates for conditional simulation. Areal covariates are motivated by a principal component analysis that indicates the seasonal spatial average is the dominant mode of variability across the domain. We find this modification to be effective in capturing the nonstationarity prevalent in interseasonal precipitation and temperature data. We further illustrate the ability of this weather generator to act as a spatiotemporal downscaler of seasonal forecasts and multidecadal projections, both of which are generally of coarse resolution.

  7. Protein (multi-)location prediction: utilizing interdependencies via a generative model

    Science.gov (United States)

    Shatkay, Hagit

    2015-01-01

    Motivation: Proteins are responsible for a multitude of vital tasks in all living organisms. Given that a protein’s function and role are strongly related to its subcellular location, protein location prediction is an important research area. While proteins move from one location to another and can localize to multiple locations, most existing location prediction systems assign only a single location per protein. A few recent systems attempt to predict multiple locations for proteins, however, their performance leaves much room for improvement. Moreover, such systems do not capture dependencies among locations and usually consider locations as independent. We hypothesize that a multi-location predictor that captures location inter-dependencies can improve location predictions for proteins. Results: We introduce a probabilistic generative model for protein localization, and develop a system based on it—which we call MDLoc—that utilizes inter-dependencies among locations to predict multiple locations for proteins. The model captures location inter-dependencies using Bayesian networks and represents dependency between features and locations using a mixture model. We use iterative processes for learning model parameters and for estimating protein locations. We evaluate our classifier MDLoc, on a dataset of single- and multi-localized proteins derived from the DBMLoc dataset, which is the most comprehensive protein multi-localization dataset currently available. Our results, obtained by using MDLoc, significantly improve upon results obtained by an initial simpler classifier, as well as on results reported by other top systems. Availability and implementation: MDLoc is available at: http://www.eecis.udel.edu/∼compbio/mdloc. Contact: shatkay@udel.edu. PMID:26072505

  8. Protein (multi-)location prediction: utilizing interdependencies via a generative model.

    Science.gov (United States)

    Simha, Ramanuja; Briesemeister, Sebastian; Kohlbacher, Oliver; Shatkay, Hagit

    2015-06-15

    Proteins are responsible for a multitude of vital tasks in all living organisms. Given that a protein's function and role are strongly related to its subcellular location, protein location prediction is an important research area. While proteins move from one location to another and can localize to multiple locations, most existing location prediction systems assign only a single location per protein. A few recent systems attempt to predict multiple locations for proteins, however, their performance leaves much room for improvement. Moreover, such systems do not capture dependencies among locations and usually consider locations as independent. We hypothesize that a multi-location predictor that captures location inter-dependencies can improve location predictions for proteins. We introduce a probabilistic generative model for protein localization, and develop a system based on it-which we call MDLoc-that utilizes inter-dependencies among locations to predict multiple locations for proteins. The model captures location inter-dependencies using Bayesian networks and represents dependency between features and locations using a mixture model. We use iterative processes for learning model parameters and for estimating protein locations. We evaluate our classifier MDLoc, on a dataset of single- and multi-localized proteins derived from the DBMLoc dataset, which is the most comprehensive protein multi-localization dataset currently available. Our results, obtained by using MDLoc, significantly improve upon results obtained by an initial simpler classifier, as well as on results reported by other top systems. MDLoc is available at: http://www.eecis.udel.edu/∼compbio/mdloc. © The Author 2015. Published by Oxford University Press.

  9. Generalist solutions to complex problems: generating practice-based evidence--the example of managing multi-morbidity.

    Science.gov (United States)

    Reeve, Joanne; Blakeman, Tom; Freeman, George K; Green, Larry A; James, Paul A; Lucassen, Peter; Martin, Carmel M; Sturmberg, Joachim P; van Weel, Chris

    2013-08-07

    A growing proportion of people are living with long term conditions. The majority have more than one. Dealing with multi-morbidity is a complex problem for health systems: for those designing and implementing healthcare as well as for those providing the evidence informing practice. Yet the concept of multi-morbidity (the presence of >2 diseases) is a product of the design of health care systems which define health care need on the basis of disease status. So does the solution lie in an alternative model of healthcare? Strengthening generalist practice has been proposed as part of the solution to tackling multi-morbidity. Generalism is a professional philosophy of practice, deeply known to many practitioners, and described as expertise in whole person medicine. But generalism lacks the evidence base needed by policy makers and planners to support service redesign. The challenge is to fill this practice-research gap in order to critically explore if and when generalist care offers a robust alternative to management of this complex problem. We need practice-based evidence to fill this gap. By recognising generalist practice as a 'complex intervention' (intervening in a complex system), we outline an approach to evaluate impact using action-research principles. We highlight the implications for those who both commission and undertake research in order to tackle this problem. Answers to the complex problem of multi-morbidity won't come from doing more of the same. We need to change systems of care, and so the systems for generating evidence to support that care. This paper contributes to that work through outlining a process for generating practice-based evidence of generalist solutions to the complex problem of person-centred care for people with multi-morbidity.

  10. Clinical application of 3D reconstruction of tracheobronchial tree with electron beam CT

    International Nuclear Information System (INIS)

    Yao Zhenwei; Shen Tianzhen

    2002-01-01

    Objective: To explore the clinical promise of CT 3D reconstruction of tracheobronchial tree (TBT) by analyzing 73 cases retrospectively. Methods: All the 73 cases were collected from October 1997 to February 2000, who were scanned by EBCT with 130 kV and 630 mA. The scanning method was continuous volume scan, the slice thickness were 3 mm or 1.5 mm. All cross-sectional images were transmitted to the INSIGHT workstation and reconstructed with SSD (shaded surface display), and the threshold setting were -500 to -300 HU. Results: 3D reconstruction of TBT with EBCT could reveal the abnormal changes of TBT by many kinds of diseases including central cancer, inflammation, bronchiectasis, saber-sheath trachea, trachea cancer, congenital disorders, post-surgical changes of lung cancer, and stenoses by adjacent benign or malignant diseases. It could be used to locate the stenoses and measure stenotic extent. Of the 35 central cancer cases with 3D reconstruction, 6 cases were pestle obstructed, 15 cases cone obstructed, 5 cases interrupted irregularly, 8 cases with eccentric stenoses, and 1 case with right stem destroyed and right upper lobe bronchus obstructed. Conclusion: 3D reconstruction of TBT has characteristic sign in the diagnosis or differential diagnosis of central airway's benign or malignant stenoses, and it is of instructional value in clinical use

  11. A fuzzy approach to the generation expansion planning problem in a multi-objective environment

    International Nuclear Information System (INIS)

    Abass, S. A.; Massoud, E. M. A.; Abass, S. A.)

    2007-01-01

    In many power system problems, the use of optimization techniques has proved inductive to reducing the costs and losses of the system. A fuzzy multi-objective decision is used for solving power system problems. One of the most important issues in the field of power system engineering is the generation expansion planning problem. In this paper, we use the concepts of membership functions to define a fuzzy decision model for generating an optimal solution for this problem. Solutions obtained by the fuzzy decision theory are always efficient and constitute the best compromise. (author)

  12. Measurements of the apparent thermal conductivity of multi-layer insulation between 20 K and 90 K

    International Nuclear Information System (INIS)

    Hurd, Joseph A.; Van Sciver, Steven W.

    2014-01-01

    NASA has the need to efficiently store cryogenic propellants in space for long periods of time. One method to improve storage efficiency is to use multi-layer insulation (MLI), a technique that minimizes the boiling rate due to radiation heat transfer. Typically, the thermal performance of MLI is determined by measuring the rate of evaporation of liquid nitrogen from a calibrated cryostat. The main limitation with this method is that testing conditions are restricted by the boiling temperature of the LN 2 , which may not match the requirements of the application. The Multi-Layer Insulation Thermal Conductivity Experiment (MIKE) at the National High Magnetic Field Laboratory is capable of measuring the effective thermal conductivity of MLI at variable boundary temperatures. MIKE uses cryo-refrigerators to control boundary temperatures in the calorimeter and a calibrated thermal link to measure the heat load. To make the measurements requested by NASA, MIKE needed to be recalibrated for the 20 K to 90 K range. Also, due to the expectation of a lower heat transfer rate, the heat load support rod material was changed to one with a lower thermal conductivity to ensure the temperature difference seen on the cold rod could be measurable at the estimated heat load. Presented are the alterations to MIKE including calibration data and heat load measurements on new load-bearing MLI supplied by NASA

  13. An Efficacious Multi-Objective Fuzzy Linear Programming Approach for Optimal Power Flow Considering Distributed Generation.

    Science.gov (United States)

    Warid, Warid; Hizam, Hashim; Mariun, Norman; Abdul-Wahab, Noor Izzri

    2016-01-01

    This paper proposes a new formulation for the multi-objective optimal power flow (MOOPF) problem for meshed power networks considering distributed generation. An efficacious multi-objective fuzzy linear programming optimization (MFLP) algorithm is proposed to solve the aforementioned problem with and without considering the distributed generation (DG) effect. A variant combination of objectives is considered for simultaneous optimization, including power loss, voltage stability, and shunt capacitors MVAR reserve. Fuzzy membership functions for these objectives are designed with extreme targets, whereas the inequality constraints are treated as hard constraints. The multi-objective fuzzy optimal power flow (OPF) formulation was converted into a crisp OPF in a successive linear programming (SLP) framework and solved using an efficient interior point method (IPM). To test the efficacy of the proposed approach, simulations are performed on the IEEE 30-busand IEEE 118-bus test systems. The MFLP optimization is solved for several optimization cases. The obtained results are compared with those presented in the literature. A unique solution with a high satisfaction for the assigned targets is gained. Results demonstrate the effectiveness of the proposed MFLP technique in terms of solution optimality and rapid convergence. Moreover, the results indicate that using the optimal DG location with the MFLP algorithm provides the solution with the highest quality.

  14. Bio-Inspired Multi-Functional Drug Transport Design Concept and Simulations.

    Science.gov (United States)

    Pidaparti, Ramana M; Cartin, Charles; Su, Guoguang

    2017-04-25

    In this study, we developed a microdevice concept for drug/fluidic transport taking an inspiration from supramolecular motor found in biological cells. Specifically, idealized multi-functional design geometry (nozzle/diffuser/nozzle) was developed for (i) fluidic/particle transport; (ii) particle separation; and (iii) droplet generation. Several design simulations were conducted to demonstrate the working principles of the multi-functional device. The design simulations illustrate that the proposed design concept is feasible for multi-functionality. However, further experimentation and optimization studies are needed to fully evaluate the multifunctional device concept for multiple applications.

  15. MAXIMIZING GROWTH AND SEXUAL MATURATION OF SHEEPSHEAD MINNOWS IN SUPPORT OF MULTI-GENERATION TEST DEVELOPMENT

    Science.gov (United States)

    Hemmer, R.L., G.M. Cripe and L.R. Goodman. In press. Maximizing Growth and Sexual Maturation of Sheepshead Minnows (Cyprinodon variegatus) in Support of Multi-Generation Test Development (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November 2004, Portland...

  16. A Gateway MultiSite recombination cloning toolkit.

    Directory of Open Access Journals (Sweden)

    Lena K Petersen

    Full Text Available The generation of DNA constructs is often a rate-limiting step in conducting biological experiments. Recombination cloning of single DNA fragments using the Gateway system provided an advance over traditional restriction enzyme cloning due to increases in efficiency and reliability. Here we introduce a series of entry clones and a destination vector for use in two, three, and four fragment Gateway MultiSite recombination cloning whose advantages include increased flexibility and versatility. In contrast to Gateway single-fragment cloning approaches where variations are typically incorporated into model system-specific destination vectors, our Gateway MultiSite cloning strategy incorporates variations in easily generated entry clones that are model system-independent. In particular, we present entry clones containing insertions of GAL4, QF, UAS, QUAS, eGFP, and mCherry, among others, and demonstrate their in vivo functionality in Drosophila by using them to generate expression clones including GAL4 and QF drivers for various trp ion channel family members, UAS and QUAS excitatory and inhibitory light-gated ion channels, and QUAS red and green fluorescent synaptic vesicle markers. We thus establish a starter toolkit of modular Gateway MultiSite entry clones potentially adaptable to any model system. An inventory of entry clones and destination vectors for Gateway MultiSite cloning has also been established (www.gatewaymultisite.org.

  17. Experimental modeling of flow-induced vibration of multi-span U-tubes in a CANDU steam generator

    International Nuclear Information System (INIS)

    Mohany, A.; Feenstra, P.; Janzen, V.P.; Richard, R.

    2009-01-01

    Flow-induced vibration of the tubes in a nuclear steam generator is a concern for designers who are trying to increase the life span of these units. The dominant excitation mechanisms are fluidelastic instability and random turbulence excitation. The outermost U-bend region of the tubes is of greatest concern because the flow is almost perpendicular to the tube axis and the unsupported span is relatively long. The support system in this region must be well designed in order to minimize fretting wear of the tubes at the support locations. Much of the previous testing was conducted on straight single-span or cantilevered tubes in cross-flow. However, the dynamic response of steam generator multi-span U-tubes with clearance supports is expected to be different. Accurate modeling of the tube dynamics is important to properly simulate the dynamic interaction of the tube and supports. This paper describes a test program that was developed to measure the dynamic response of a bundle of steam generator U-tubes with Anti-Vibration Bar (AVB) supports, subjected to Freon two-phase cross-flow. The tube bundle has similar geometrical conditions to those expected for future CANDU steam generators. Future steam generators will be larger than previous CANDU steam generators, nearly twice the heat transfer area, with significant changes in process conditions in the U-bend region, such as increased steam quality and a broader range of flow velocities. This test program was initiated at AECL to demonstrate that the tube support design for future CANDU steam generators will meet the stringent requirements associated with a 60 year design life. The main objective of the tests is to address the issue of in-plane and out-of-plane fluidelastic instability and random turbulent excitation of a U-tube bundle with Anti-Vibration Bar (AVB) supports. Details of the test rig, measurement techniques and preliminary instrumentation results are described in the paper. (author)

  18. Stochastic generation of multi-site daily precipitation focusing on extreme events

    Directory of Open Access Journals (Sweden)

    G. Evin

    2018-01-01

    Full Text Available Many multi-site stochastic models have been proposed for the generation of daily precipitation, but they generally focus on the reproduction of low to high precipitation amounts at the stations concerned. This paper proposes significant extensions to the multi-site daily precipitation model introduced by Wilks, with the aim of reproducing the statistical features of extremely rare events (in terms of frequency and magnitude at different temporal and spatial scales. In particular, the first extended version integrates heavy-tailed distributions, spatial tail dependence, and temporal dependence in order to obtain a robust and appropriate representation of the most extreme precipitation fields. A second version enhances the first version using a disaggregation method. The performance of these models is compared at different temporal and spatial scales on a large region covering approximately half of Switzerland. While daily extremes are adequately reproduced at the stations by all models, including the benchmark Wilks version, extreme precipitation amounts at larger temporal scales (e.g., 3-day amounts are clearly underestimated when temporal dependence is ignored.

  19. Transnasal tracheobronchial stenting for malignant airway narrowing under local anesthesia: Our experience of treating three cases using this technique

    Directory of Open Access Journals (Sweden)

    Jayanta Medhi

    2016-01-01

    Full Text Available Purpose: To study the technical feasibility of tracheobronchial stenting via transnasal route under bronchoscopy and fluoroscopic guidance in severe malignant airway strictures using self-expandable nitinol stents. Materials and Methods: We describe three patients with malignant airway strictures, treated entirely via transnasal route under local anesthesia using bronchoscopic and fluoroscopic guidance. Nasal route allowed convenient access to the airway for the bronchoscope across the stricture and a guidewire was introduced through its working channel. The 18F tracheal stent and the 6F bronchial stent assembly could be easily introduced and deployed under bronchoscopic (reintroduced through the other nostril and fluoroscopic guidance. Results: We achieved technical success in all the three patients with immediate relief of dyspnea. Conclusion: Transnasal airway stenting with self-expandable nitinol stent using bronchoscopic and fluoroscopic guidance under local anesthesia is a safe and effective method with minimal patient discomfort.

  20. A correção das estenoses traqueobrônquicas mediante o emprego de órteses Therapeutic management of tracheobronchial stenosis with stent application

    Directory of Open Access Journals (Sweden)

    MAURÍCIO GUIDI SAUERESSIG

    2002-04-01

    Full Text Available O tratamento cirúrgico do paciente com estenose traqueobrônquica exige uma avaliação individualizada em razão da complexidade de sua origem, sendo a traqueoplastia considerada a modalidade ideal. As causas mais comuns de estenose são devidas à intubação traqueal e ao desenvolvimento de neoplasias e estas condições são justamente as que mais se beneficiam com o tratamento endoscópico quando a correção cirúrgica não está indicada. Na atualidade, os meios endoscópicos incluem a aplicação de diversos tipos de laser e sondas de dilatação, habitualmente com o uso de broncoscópio rígido, e emprego de radioterapia e órteses, separadamente ou em associação. Basicamente, as órteses são de dois tipos: metálicas e de silicone. As metálicas têm sua indicação mais freqüente para os casos de traqueomalacia e estenoses por compressão neoplásica extrínseca. Nos casos de obstrução da via aérea por inflamação aguda, restrita à sua luz ou sem envolvimento mais profundo da parede traqueobrônquica, ou em presença de neoplasia endoluminal, é recomendável a órtese de silicone. Embora em algumas situações essas diversas formas de tratamento possam ser intercambiáveis, não costumam ser a regra. Portanto, a estratégia terapêutica visando à resolução mais eficaz da estenose traqueobrônquica baseia-se na seleção dos métodos empregados desde o primeiro tratamento.The surgical treatment of patients with tracheobronchial stenosis requires individualized attention due to the complexity of its origin though tracheoplasty is considered to be the ideal procedure. The most common causes of stenosis are tracheal intubation and the development of neoplasias. These are the very conditions that most benefit from endoscopic treatment when surgical correction is not indicated. Today, endoscopic procedures include the application of different kinds of laser and dilators usually delivered with a rigid bronchoscope, as well as

  1. A least squares method for a longitudinal fin with temperature dependent internal heat generation and thermal conductivity

    International Nuclear Information System (INIS)

    Aziz, A.; Bouaziz, M.N.

    2011-01-01

    Highlights: → Analytical solutions for a rectangular fin with temperature dependent heat generation and thermal conductivity. → Graphs give temperature distributions and fin efficiency. → Comparison of analytical and numerical solutions. → Method of least squares used for the analytical solutions. - Abstract: Approximate but highly accurate solutions for the temperature distribution, fin efficiency, and optimum fin parameter for a constant area longitudinal fin with temperature dependent internal heat generation and thermal conductivity are derived analytically. The method of least squares recently used by the authors is applied to treat the two nonlinearities, one associated with the temperature dependent internal heat generation and the other due to temperature dependent thermal conductivity. The solution is built from the classical solution for a fin with uniform internal heat generation and constant thermal conductivity. The results are presented graphically and compared with the direct numerical solutions. The analytical solutions retain their accuracy (within 1% of the numerical solution) even when there is a 60% increase in thermal conductivity and internal heat generation at the base temperature from their corresponding values at the sink temperature. The present solution is simple (involves hyperbolic functions only) compared with the fairly complex approximate solutions based on the homotopy perturbation method, variational iteration method, and the double series regular perturbation method and offers high accuracy. The simple analytical expressions for the temperature distribution, the fin efficiency and the optimum fin parameter are convenient for use by engineers dealing with the design and analysis of heat generating fins operating with a large temperature difference between the base and the environment.

  2. Design of flexible polyphenylene proton-conducting membrane for next-generation fuel cells.

    Science.gov (United States)

    Miyake, Junpei; Taki, Ryunosuke; Mochizuki, Takashi; Shimizu, Ryo; Akiyama, Ryo; Uchida, Makoto; Miyatake, Kenji

    2017-10-01

    Proton exchange membrane fuel cells (PEMFCs) are promising devices for clean power generation in automotive, stationary, and portable applications. Perfluorosulfonic acid (PFSA) ionomers (for example, Nafion) have been the benchmark PEMs; however, several problems, including high gas permeability, low thermal stability, high production cost, and environmental incompatibility, limit the widespread dissemination of PEMFCs. It is believed that fluorine-free PEMs can potentially address all of these issues; however, none of these membranes have simultaneously met the criteria for both high performance (for example, proton conductivity) and durability (for example, mechanical and chemical stability). We present a polyphenylene-based PEM (SPP-QP) that fulfills the required properties for fuel cell applications. The newly designed PEM exhibits very high proton conductivity, excellent membrane flexibility, low gas permeability, and extremely high stability, with negligible degradation even under accelerated degradation conditions, which has never been achieved with existing fluorine-free PEMs. The polyphenylene PEM also exhibits reasonably high fuel cell performance, with excellent durability under practical conditions. This new PEM extends the limits of existing fluorine-free proton-conductive materials and will help to realize the next generation of PEMFCs via cost reduction as well as the performance improvement compared to the present PFSA-based PEMFC systems.

  3. Generation of a multi-photon Greenberger-Horne-Zeilinger state with linear optical elements and photon detectors

    International Nuclear Information System (INIS)

    Zou, X B; Pahlke, K; Mathis, W

    2005-01-01

    We present a scheme to generate a multi-photon Greenberger-Horne-Zeilinger (GHZ) state by using single-photon sources, linear optical elements and photon detectors. Such a maximum entanglement has wide applications in the demonstration of quantum nonlocality and quantum information processing

  4. Simulating secondary organic aerosol in a regional air quality model using the statistical oxidation model - Part 1: Assessing the influence of constrained multi-generational ageing

    Science.gov (United States)

    Jathar, S. H.; Cappa, C. D.; Wexler, A. S.; Seinfeld, J. H.; Kleeman, M. J.

    2016-02-01

    Multi-generational oxidation of volatile organic compound (VOC) oxidation products can significantly alter the mass, chemical composition and properties of secondary organic aerosol (SOA) compared to calculations that consider only the first few generations of oxidation reactions. However, the most commonly used state-of-the-science schemes in 3-D regional or global models that account for multi-generational oxidation (1) consider only functionalization reactions but do not consider fragmentation reactions, (2) have not been constrained to experimental data and (3) are added on top of existing parameterizations. The incomplete description of multi-generational oxidation in these models has the potential to bias source apportionment and control calculations for SOA. In this work, we used the statistical oxidation model (SOM) of Cappa and Wilson (2012), constrained by experimental laboratory chamber data, to evaluate the regional implications of multi-generational oxidation considering both functionalization and fragmentation reactions. SOM was implemented into the regional University of California at Davis / California Institute of Technology (UCD/CIT) air quality model and applied to air quality episodes in California and the eastern USA. The mass, composition and properties of SOA predicted using SOM were compared to SOA predictions generated by a traditional two-product model to fully investigate the impact of explicit and self-consistent accounting of multi-generational oxidation.Results show that SOA mass concentrations predicted by the UCD/CIT-SOM model are very similar to those predicted by a two-product model when both models use parameters that are derived from the same chamber data. Since the two-product model does not explicitly resolve multi-generational oxidation reactions, this finding suggests that the chamber data used to parameterize the models captures the majority of the SOA mass formation from multi-generational oxidation under the conditions

  5. Multi-sphere unit cell model to calculate the effective thermal conductivity in pebble bed reactors

    International Nuclear Information System (INIS)

    Van Antwerpen, W.; Rousseau, P.G.; Du Toit, C.G.

    2010-01-01

    A proper understanding of the mechanisms of heat transfer, fluid flow and pressure drop through a packed bed of spheres is of utmost importance in the design of a high temperature Pebble Bed Reactor (PBR). While the gas flows predominantly in the axial direction through the bed, the total effective thermal conductivity is a lumped parameter that characterises the total heat transfer in the radial direction through the packed bed. The study of the effective thermal conductivity is important because it forms an intricate part of the self-acting decay heat removal chain, which is directly related to the PBR safety case. The effective thermal conductivity is the summation of various heat transport phenomena. These are the enhanced thermal conductivity due to turbulent mixing as the fluid passes through the voids between pebbles, heat transfer due to the movement of the solid spheres and thermal conduction and thermal radiation between the spheres in a stagnant fluid environment. In this study, the conduction and radiation between the spheres are investigated. Firstly, existing correlations for the effective thermal conductivity are investigated, with particular attention given to its applicability in the near-wall region. Several phenomena in particular are examined namely: conduction through the spheres, conduction through the contact area between the spheres, conduction through the gas phase and radiation between solid surfaces. A new approach to simulate the effective thermal conductivity for randomly packed beds is then presented, namely the so-called Multi-sphere Unit Cell Model. The model is validated by comparing the results with that obtained in experiments. (authors)

  6. Effective thermal conductivity of a heat generating rod bundle dissipating heat by natural convection and radiation

    International Nuclear Information System (INIS)

    Senve, Vinay; Narasimham, G.S.V.L.

    2011-01-01

    Highlights: → Transport processes in isothermal hexagonal sheath with 19 heat generating rods is studied. → Correlation is given to predict the maximum temperature considering all transport processes. → Effective thermal conductivity of rod bundle can be obtained using max temperature. → Data on the critical Rayleigh numbers for p/d ratios of 1.1-2.0 is presented. → Radiative heat transfer contributes to heat dissipation of 38-65% of total heat. - Abstract: A numerical study of conjugate natural convection and surface radiation in a horizontal hexagonal sheath housing 19 solid heat generating rods with cladding and argon as the fill gas, is performed. The natural convection in the sheath is driven by the volumetric heat generation in the solid rods. The problem is solved using the FLUENT CFD code. A correlation is obtained to predict the maximum temperature in the rod bundle for different pitch-to-diameter ratios and heat generating rates. The effective thermal conductivity is related to the heat generation rate, maximum temperature and the sheath temperature. Results are presented for the dimensionless maximum temperature, Rayleigh number and the contribution of radiation with changing emissivity, total wattage and the pitch-to-diameter ratio. In the simulation of a larger system that contains a rod bundle, the effective thermal conductivity facilitates simplified modelling of the rod bundle by treating it as a solid of effective thermal conductivity. The parametric studies revealed that the contribution of radiation can be 38-65% of the total heat generation, for the parameter ranges chosen. Data for critical Rayleigh number above which natural convection comes into effect is also presented.

  7. Experiences from a pilot study on how to conduct a qualitative multi-country research project regarding use of antibiotics in Southeast Europe

    DEFF Research Database (Denmark)

    Kaae, Susanne; Sporrong, Sofia Kälvemark; Traulsen, Janine Morgall

    2016-01-01

    regarding how to conduct these types of research projects by evaluating a pilot study of the project. METHODS: Local data collectors conducted the study according to a developed protocol and evaluated the study with the responsible researcher-team from University of Copenhagen. The pilot study focused......BACKGROUND: In 2014, a qualitative multi-country research project was launched to study the reasons behind the high use of antibiotics in regions of Southeast Europe by using previously untrained national interviewers (who were engaged in other antibiotic microbial resistance-related investigations......) to conduct qualitative interviews with local patients, physicians and pharmacists. Little knowledge exists about how to implement qualitative multi-country research collaborations involving previously untrained local data collectors. The aim of this paper was therefore to contribute to the knowledge...

  8. Example-based illustrations of design, conduct, analysis and result interpretation of multi-regional clinical trials.

    Science.gov (United States)

    Quan, Hui; Mao, Xuezhou; Tanaka, Yoko; Binkowitz, Bruce; Li, Gang; Chen, Josh; Zhang, Ji; Zhao, Peng-Liang; Ouyang, Soo Peter; Chang, Mark

    2017-07-01

    Extensive research has been conducted in the Multi-Regional Clinical Trial (MRCT) area. To effectively apply an appropriate approach to a MRCT, we need to synthesize and understand the features of different approaches. In this paper, examples are used to illustrate considerations regarding design, conduct, analysis and interpretation of result of MRCTs. We start with a brief discussion of region definitions and the scenarios where different regions have differing requirements for a MRCT. We then compare different designs and models as well as the corresponding interpretation of the results. We highlight the importance of paying special attention to trial monitoring and conduct to prevent potential issues associated with the final trial results. Besides evaluating the overall treatment effect for the entire MRCT, we also consider other key analyses including quantification of regional treatment effects within a MRCT, and assessment of consistency of these regional treatment effects. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. A novel multi-agent decentralized win or learn fast policy hill-climbing with eligibility trace algorithm for smart generation control of interconnected complex power grids

    International Nuclear Information System (INIS)

    Xi, Lei; Yu, Tao; Yang, Bo; Zhang, Xiaoshun

    2015-01-01

    Highlights: • Proposing a decentralized smart generation control scheme for the automatic generation control coordination. • A novel multi-agent learning algorithm is developed to resolve stochastic control problems in power systems. • A variable learning rate are introduced base on the framework of stochastic games. • A simulation platform is developed to test the performance of different algorithms. - Abstract: This paper proposes a multi-agent smart generation control scheme for the automatic generation control coordination in interconnected complex power systems. A novel multi-agent decentralized win or learn fast policy hill-climbing with eligibility trace algorithm is developed, which can effectively identify the optimal average policies via a variable learning rate under various operation conditions. Based on control performance standards, the proposed approach is implemented in a flexible multi-agent stochastic dynamic game-based smart generation control simulation platform. Based on the mixed strategy and average policy, it is highly adaptive in stochastic non-Markov environments and large time-delay systems, which can fulfill automatic generation control coordination in interconnected complex power systems in the presence of increasing penetration of decentralized renewable energy. Two case studies on both a two-area load–frequency control power system and the China Southern Power Grid model have been done. Simulation results verify that multi-agent smart generation control scheme based on the proposed approach can obtain optimal average policies thus improve the closed-loop system performances, and can achieve a fast convergence rate with significant robustness compared with other methods

  10. 78 FR 9678 - Multi-stakeholder Process To Develop a Voluntary Code of Conduct for Smart Grid Data Privacy

    Science.gov (United States)

    2013-02-11

    ... providing consumer energy use services. DATES: Tuesday, February 26, 2013 (9:30 a.m. to 4:30 p.m., Eastern... Privacy and Promoting Innovation in the Global Digital Economy \\2\\ (Privacy Blueprint). The Privacy Blueprint outlines a multi-stakeholder process for developing voluntary codes of conduct that, if adopted by...

  11. Sustainability Assessment of Electricity Generation Technologies in Egypt Using Multi-Criteria Decision Analysis

    Directory of Open Access Journals (Sweden)

    Mostafa Shaaban

    2018-05-01

    Full Text Available Future electricity planning necessitates a thorough multi-faceted analysis of the available technologies in order to secure the energy supply for coming generations. To cope with worldwide concerns over sustainable development and meet the growing demands of electricity we assess the future potential technologies in Egypt through covering their technical, economic, environmental and social aspects. In this study we fill the gap of a lacking sustainability assessment of energy systems in Egypt where most of the studies focus mainly on the economic and technical aspects of planning future installation of power plants in Egypt. Furthermore, we include the stakeholder preferences of the indicators in the energy sector into our assessment. Moreover, we perform a sensitivity analysis through single dimension assessment scenarios of the technologies as well as a sustainable scenario with equal preferences of all dimensions of the sustainability. We employ two multi-criteria decision analysis (MCDA methodologies: the analytical hierarchy process for weighing the assessment criteria, and the weighted sum method for generating a general integrated sustainability index for each technology. The study investigates seven technologies: coal, natural gas, wind, concentrated solar power, photovoltaics, biomass and nuclear. The results reveal a perfect matching between the ranking of the technologies by the stakeholders and the sustainable scenario showing the highest ranking for natural gas and the lowest for nuclear and coal. There is a strong potential for renewable energy technologies to invade the electricity market in Egypt where they achieve the second ranking after natural gas. The Monte-Carlo approach gives photovoltaics a higher ranking over concentrated solar power as compared to the sample data ranking. The study concludes the importance of a multi-dimensional evaluation of the technologies while considering the preferences of the stakeholders in

  12. NSGA-II algorithm for multi-objective generation expansion planning problem

    Energy Technology Data Exchange (ETDEWEB)

    Murugan, P.; Kannan, S. [Electronics and Communication Engineering Department, Arulmigu Kalasalingam College of Engineering, Krishnankoil 626190, Tamilnadu (India); Baskar, S. [Electrical Engineering Department, Thiagarajar College of Engineering, Madurai 625015, Tamilnadu (India)

    2009-04-15

    This paper presents an application of Elitist Non-dominated Sorting Genetic Algorithm version II (NSGA-II), to multi-objective generation expansion planning (GEP) problem. The GEP problem is considered as a two-objective problem. The first objective is the minimization of investment cost and the second objective is the minimization of outage cost (or maximization of reliability). To improve the performance of NSGA-II, two modifications are proposed. One modification is incorporation of Virtual Mapping Procedure (VMP), and the other is introduction of controlled elitism in NSGA-II. A synthetic test system having 5 types of candidate units is considered here for GEP for a 6-year planning horizon. The effectiveness of the proposed modifications is illustrated in detail. (author)

  13. Experimental study of the effect of Nd:YAG laser on dental hard tissues: comparison between multi-pulse and free-generation emission code

    International Nuclear Information System (INIS)

    Carballosa Amor, A.; Tellez Jimenez, H.; Ponce Flores, E.; Flores Reyes, T.

    2016-01-01

    The aim of this study is to compare and contrast the morphological changes on dental hard tissue when irradiated with a Nd: YAG laser both on multi-pulse mode, with a Q: Switch of Cr: YAG passive, and on free generation mode. The experimental sample consisted of 6 healthy third molars which were divided equally and randomly between the two emission methods. The depths of each perforation were measured by optical coherence tomography (OCT). It was noted that, despite being less energy in the multi-pulse mode, the first three shots in this achieved deeper cavities than the ones on the free generation mode. Also, less damage to surrounding tissue were obtained on multi-pulse mode. (Author)

  14. A comprehensive analysis about thermal conductivity of multi-layer graphene with N-doping, -CH3 group, and single vacancy

    Science.gov (United States)

    Si, Chao; Li, Liang; Lu, Gui; Cao, Bing-Yang; Wang, Xiao-Dong; Fan, Zhen; Feng, Zhi-Hai

    2018-04-01

    Graphene has received great attention due to its fascinating thermal properties. The inevitable defects in graphene, such as single vacancy, doping, and functional group, greatly affect the thermal conductivity. The sole effect of these defects on the thermal conductivity has been widely studied, while the mechanisms of the coupling effects are still open. We studied the combined effect of defects with N-doping, the -CH3 group, and single vacancy on the thermal conductivity of multi-layer graphene at various temperatures using equilibrium molecular dynamics with the Green-Kubo theory. The Taguchi orthogonal algorithm is used to evaluate the sensitivity of N-doping, the -CH3 group, and single vacancy. Sole factor analysis shows that the effect of single vacancy on thermal conductivity is always the strongest at 300 K, 700 K, and 1500 K. However, for the graphene with three defects, the single vacancy defect only plays a significant role in the thermal conductivity modification at 300 K and 700 K, while the -CH3 group dominates the thermal conductivity reduction at 1500 K. The phonon dispersion is calculated using a spectral energy density approach to explain such a temperature dependence. The combined effect of the three defects further decreases the thermal conductivity compared to any sole defect at both 300 K and 700 K. The weaker single vacancy effect is due to the stronger Umklapp scattering at 1500 K, at which the combined effect seriously covers almost all the energy gaps in the phonon dispersion relation, significantly reducing the phonon lifetimes. Therefore, the temperature dependence only appears on the multi-layer graphene with combined defects.

  15. Experiences from a pilot study on how to conduct a qualitative multi-country research project regarding use of antibiotics in Southeast Europe.

    Science.gov (United States)

    Kaae, Susanne; Sporrong, Sofia Kälvemark; Traulsen, Janine Morgall; Wallach Kildemoes, Helle; Nørgaard, Lotte Stig; Jakupi, Arianit; Raka, Denis; Gürpinar, Emre Umut; Alkan, Ali; Hoxha, Iris; Malaj, Admir; Cantarero, Lourdes Arevalo

    2016-01-01

    In 2014, a qualitative multi-country research project was launched to study the reasons behind the high use of antibiotics in regions of Southeast Europe by using previously untrained national interviewers (who were engaged in other antibiotic microbial resistance-related investigations) to conduct qualitative interviews with local patients, physicians and pharmacists. Little knowledge exists about how to implement qualitative multi-country research collaborations involving previously untrained local data collectors. The aim of this paper was therefore to contribute to the knowledge regarding how to conduct these types of research projects by evaluating a pilot study of the project. Local data collectors conducted the study according to a developed protocol and evaluated the study with the responsible researcher-team from University of Copenhagen. The pilot study focused on 'local ownership', 'research quality' and 'feasibility' with regard to successful implementation and evaluation. The evaluation was achieved by interpreting 'Skype' and 'face to face' meetings and email correspondence by applying 'critical common sense'. Local data collectors achieved a sense of joint ownership. Overall, the protocol worked well. Several minor challenges pertaining to research quality and feasibility were identified, in particular obtaining narratives when conducting interviews and recruiting patients for the study. Furthermore, local data collectors found it difficult to allocate sufficient time to the project. Solutions were discussed and added to the protocol. Despite the challenges, it was possible to achieve an acceptable scientific level of research when conducting qualitative multi-country research collaboration under the given circumstances. Specific recommendations to achieve this are provided by the authors.

  16. Presenting a multi-objective generation scheduling model for pricing demand response rate in micro-grid energy management

    International Nuclear Information System (INIS)

    Aghajani, G.R.; Shayanfar, H.A.; Shayeghi, H.

    2015-01-01

    Highlights: • Using DRPs to cover the uncertainties resulted from power generation by WT and PV. • Proposing the use of price-offer packages and amount of DR for implement DRPs. • Considering a multi-objective scheduling model and use of MOPSO algorithm. - Abstract: In this paper, a multi-objective energy management system is proposed in order to optimize micro-grid (MG) performance in a short-term in the presence of Renewable Energy Sources (RESs) for wind and solar energy generation with a randomized natural behavior. Considering the existence of different types of customers including residential, commercial, and industrial consumers can participate in demand response programs. As with declare their interruptible/curtailable demand rate or select from among different proposed prices so as to assist the central micro-grid control in terms of optimizing micro-grid operation and covering energy generation uncertainty from the renewable sources. In this paper, to implement Demand Response (DR) schedules, incentive-based payment in the form of offered packages of price and DR quantity collected by Demand Response Providers (DRPs) is used. In the typical micro-grid, different technologies including Wind Turbine (WT), PhotoVoltaic (PV) cell, Micro-Turbine (MT), Full Cell (FC), battery hybrid power source and responsive loads are used. The simulation results are considered in six different cases in order to optimize operation cost and emission with/without DR. Considering the complexity and non-linearity of the proposed problem, Multi-Objective Particle Swarm Optimization (MOPSO) is utilized. Also, fuzzy-based mechanism and non-linear sorting system are applied to determine the best compromise considering the set of solutions from Pareto-front space. The numerical results represented the effect of the proposed Demand Side Management (DSM) scheduling model on reducing the effect of uncertainty obtained from generation power and predicted by WT and PV in a MG.

  17. State-of-the-Art: DTM Generation Using Airborne LIDAR Data

    Directory of Open Access Journals (Sweden)

    Ziyue Chen

    2017-01-01

    Full Text Available Digital terrain model (DTM generation is the fundamental application of airborne Lidar data. In past decades, a large body of studies has been conducted to present and experiment a variety of DTM generation methods. Although great progress has been made, DTM generation, especially DTM generation in specific terrain situations, remains challenging. This research introduces the general principles of DTM generation and reviews diverse mainstream DTM generation methods. In accordance with the filtering strategy, these methods are classified into six categories: surface-based adjustment; morphology-based filtering, triangulated irregular network (TIN-based refinement, segmentation and classification, statistical analysis and multi-scale comparison. Typical methods for each category are briefly introduced and the merits and limitations of each category are discussed accordingly. Despite different categories of filtering strategies, these DTM generation methods present similar difficulties when implemented in sharply changing terrain, areas with dense non-ground features and complicated landscapes. This paper suggests that the fusion of multi-sources and integration of different methods can be effective ways for improving the performance of DTM generation.

  18. State-of-the-Art: DTM Generation Using Airborne LIDAR Data

    Science.gov (United States)

    Chen, Ziyue; Gao, Bingbo; Devereux, Bernard

    2017-01-01

    Digital terrain model (DTM) generation is the fundamental application of airborne Lidar data. In past decades, a large body of studies has been conducted to present and experiment a variety of DTM generation methods. Although great progress has been made, DTM generation, especially DTM generation in specific terrain situations, remains challenging. This research introduces the general principles of DTM generation and reviews diverse mainstream DTM generation methods. In accordance with the filtering strategy, these methods are classified into six categories: surface-based adjustment; morphology-based filtering, triangulated irregular network (TIN)-based refinement, segmentation and classification, statistical analysis and multi-scale comparison. Typical methods for each category are briefly introduced and the merits and limitations of each category are discussed accordingly. Despite different categories of filtering strategies, these DTM generation methods present similar difficulties when implemented in sharply changing terrain, areas with dense non-ground features and complicated landscapes. This paper suggests that the fusion of multi-sources and integration of different methods can be effective ways for improving the performance of DTM generation. PMID:28098810

  19. Simulation of magnetic drug targeting through tracheobronchial airways in the presence of an external non-uniform magnetic field using Lagrangian magnetic particle tracking

    International Nuclear Information System (INIS)

    Pourmehran, O.; Rahimi-Gorji, M.; Gorji-Bandpy, M.; Gorji, T.B.

    2015-01-01

    Drug delivery technologies are an important area within biomedicine. Targeted drug delivery aims to reduce the undesired side effects of drug usage by directing or capturing the active agents near a desired site within the body. Herein, a numerical investigation of magnetic drug targeting (MDT) using aerosol drugs named polystyrene particle (PMS40) in human lung is presented considering one-way coupling on the transport and capture of the magnetic particle. A realistic 3D geometry based on CT scan images is provided for CFD simulation. An external non-uniform magnetic field is applied. Parametric investigation is conducted and the influence of particle diameter, magnetic source position, and magnetic number (Mn) on the deposition efficiency and particle behavior is reported. According to the results, the magnetic field increased deposition efficiency of particles in a target region, the efficiency of deposition and MDT technique has a direct relation with increasing the particle diameter for magnetic number of 1 Tesla (T) and lower (Mn≤1(T)). Also it can be seen that there is an inverse relation between the particle diameter and deposition efficiency when Mn is more than 1 (T). - Highlights: • A realistic 3D geometry of human tracheobronchial airway based on CT scan image. • External non-uniform magnetic field applied to target the magnetic drug career. • Lagrangian particle tracking using discrete phase model applied. • The efficiency of deposition is dependent of magnetic number and particle diameter

  20. Simulation of magnetic drug targeting through tracheobronchial airways in the presence of an external non-uniform magnetic field using Lagrangian magnetic particle tracking

    Energy Technology Data Exchange (ETDEWEB)

    Pourmehran, O., E-mail: oveis87@yahoo.com; Rahimi-Gorji, M.; Gorji-Bandpy, M., E-mail: gorji@nit.ac.ir; Gorji, T.B.

    2015-11-01

    Drug delivery technologies are an important area within biomedicine. Targeted drug delivery aims to reduce the undesired side effects of drug usage by directing or capturing the active agents near a desired site within the body. Herein, a numerical investigation of magnetic drug targeting (MDT) using aerosol drugs named polystyrene particle (PMS40) in human lung is presented considering one-way coupling on the transport and capture of the magnetic particle. A realistic 3D geometry based on CT scan images is provided for CFD simulation. An external non-uniform magnetic field is applied. Parametric investigation is conducted and the influence of particle diameter, magnetic source position, and magnetic number (Mn) on the deposition efficiency and particle behavior is reported. According to the results, the magnetic field increased deposition efficiency of particles in a target region, the efficiency of deposition and MDT technique has a direct relation with increasing the particle diameter for magnetic number of 1 Tesla (T) and lower (Mn≤1(T)). Also it can be seen that there is an inverse relation between the particle diameter and deposition efficiency when Mn is more than 1 (T). - Highlights: • A realistic 3D geometry of human tracheobronchial airway based on CT scan image. • External non-uniform magnetic field applied to target the magnetic drug career. • Lagrangian particle tracking using discrete phase model applied. • The efficiency of deposition is dependent of magnetic number and particle diameter.

  1. Multi-objective mean-variance-skewness model for generation portfolio allocation in electricity markets

    Energy Technology Data Exchange (ETDEWEB)

    Pindoriya, N.M.; Singh, S.N. [Department of Electrical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016 (India); Singh, S.K. [Indian Institute of Management Lucknow, Lucknow 226013 (India)

    2010-10-15

    This paper proposes an approach for generation portfolio allocation based on mean-variance-skewness (MVS) model which is an extension of the classical mean-variance (MV) portfolio theory, to deal with assets whose return distribution is non-normal. The MVS model allocates portfolios optimally by considering the maximization of both the expected return and skewness of portfolio return while simultaneously minimizing the risk. Since, it is competing and conflicting non-smooth multi-objective optimization problem, this paper employed a multi-objective particle swarm optimization (MOPSO) based meta-heuristic technique to provide Pareto-optimal solution in a single simulation run. Using a case study of the PJM electricity market, the performance of the MVS portfolio theory based method and the classical MV method is compared. It has been found that the MVS portfolio theory based method can provide significantly better portfolios in the situation where non-normally distributed assets exist for trading. (author)

  2. Multi-objective mean-variance-skewness model for generation portfolio allocation in electricity markets

    International Nuclear Information System (INIS)

    Pindoriya, N.M.; Singh, S.N.; Singh, S.K.

    2010-01-01

    This paper proposes an approach for generation portfolio allocation based on mean-variance-skewness (MVS) model which is an extension of the classical mean-variance (MV) portfolio theory, to deal with assets whose return distribution is non-normal. The MVS model allocates portfolios optimally by considering the maximization of both the expected return and skewness of portfolio return while simultaneously minimizing the risk. Since, it is competing and conflicting non-smooth multi-objective optimization problem, this paper employed a multi-objective particle swarm optimization (MOPSO) based meta-heuristic technique to provide Pareto-optimal solution in a single simulation run. Using a case study of the PJM electricity market, the performance of the MVS portfolio theory based method and the classical MV method is compared. It has been found that the MVS portfolio theory based method can provide significantly better portfolios in the situation where non-normally distributed assets exist for trading. (author)

  3. A triple hybrid micropower generator with simultaneous multi-mode energy harvesting

    Science.gov (United States)

    Uluşan, H.; Chamanian, S.; Pathirana, W. P. M. R.; Zorlu, Ö.; Muhtaroğlu, A.; Külah, H.

    2018-01-01

    This study presents a triple hybrid energy harvesting system that combines harvested power from thermoelectric (TE), vibration-based electromagnetic (EM) and piezoelectric (PZT) harvesters into a single DC supply. A power management circuit is designed and implemented in 180 nm standard CMOS technology based on the distinct requirements of each harvester, and is terminated with a Schottky diode to avoid reverse current flow. The system topology hence supports simultaneous power generation and delivery from low and high frequency vibrations as well as temperature differences in the environment. The ultra-low DC voltage harvested from TE generator is boosted with a cross-coupled charge-pump driven by an LC oscillator with fully-integrated center-tapped differential inductors. The EM harvester output was rectified with a self-powered and low drop-out AC/DC doubler circuit. The PZT interface electronics benefits from peak-to-peak cycle of the harvested voltage through a negative voltage converter followed by synchronous power extraction and DC-to-DC conversion through internal switches, and an external inductor. The hybrid system was tested with a wearable in-house EM energy harvester placed wrist of a jogger, a commercial low volume PZT harvester, and DC supply as the TE generator output. The system generates more than 1.2 V output for load resistances higher than 50 kΩ, which corresponds to 24 μW to power wearable sensors. Simultaneous multi-mode operation achieves higher voltage and power compared to stand-alone harvesting circuits, and generates up to 110 μW of output power. This is the first hybrid harvester circuit that simultaneously extracts energy from three independent sources, and delivers a single DC output.

  4. Multi-target Wastage Phenomena on Steam Generator Tubes During an SWR Event

    International Nuclear Information System (INIS)

    Jeong, Ji Young; Kim, Jong Man; Kim, Tae Joon; Eoh, Jae Hyuk; Choi, Jong Hyeun; Lee, Yong Bum

    2011-01-01

    The Korean sodium cooled fast reactor, KALIMER- 600 (Korea Advanced LIquid MEtal Reactor) of which the electric output is 600MWe, was developed. The steam generator (SG) of this system is a shell-and-tube type counter-current flow heat exchanger, which is vertically oriented with fixed tube-sheets. A direct heat exchange occurs between the shell-side sodium and the tube-side water at the SG unit. Feed-water enters the inlet nozzle at the lower part of the unit and it flows upward along the helically coiled heat transfer tubes. The inflow sodium is cooled down at the bundle region and then flows out through the sodium outlet nozzle at the bottom of the unit. The typical configuration of the KALIMER-600 SG is shown in Figure 1. In a steam generator, sodium and water are separated by the heat transfer tube wall and it makes a strong pressure boundary between the shell-side sodium and the tube-side water/steam. For this reason, if there is a small hole or crack, even with a pin hole, on heat transfer tubes, a large amount of water/steam would leak into the liquid sodium due to the high pressure difference more than 150 bars, and an exothermic sodium-water chemical reaction takes place as a result. This type of sodium-water reaction (SWR) has been considered as one of the most important safety issues to be resolved. From previous studies, it was obviously figured out that the number of ruptured tubes during an SWR event is one of the most significant factors to determine the temperature and pressure transient. Any subsequent tube rupture behavior in the vicinity of the initially postulated single ruptured tube should be evaluated by considering the single- and multi-target wastage phenomena. Wastage is defined as damage to the structural material (e.g. heat transfer tubes) due to an impingement of the highly corrosive reaction product. Since the impingement may cause wastage of the neighboring heat transfer tubes, a subsequent tube failure can occur in a very short time

  5. Physical phenomena in a low-temperature non-equilibrium plasma and in MHD generators with non-equilibrium conductivity

    International Nuclear Information System (INIS)

    Velikhov, E.P.; Golubev, V.S.; Dykhne, A.M.

    1976-01-01

    The paper assesses the position in 1975 of theoretical and experimental work on the physics of a magnetohydrodynamic generator with non-equilibrium plasma conductivity. This research started at the beginning of the 1960s; as work on the properties of thermally non-equilibrium plasma in magnetic fields and also in MHD generator ducts progressed, a number of phenomena were discovered and investigated that had either been unknown in plasma physics or had remained uninvestigated until that time: ionization instability and ionization turbulence of plasma in a magnetic field, acoustic instability of a plasma with anisotropic conductivity, the non-equilibrium ionization wave and the energy balance of a non-equilibrium plasma. At the same time, it was discovered what physical requirements an MHD generator with non-equilibrium conductivity must satisfy to achieve high efficiency in converting the thermal or kinetic energy of the gas flow into electric energy. The experiments on MHD power generation with thermally non-equilibrium plasma carried out up to 1975 indicated that it should be possible to achieve conversion efficiencies of up to 20-30%. (author)

  6. Multi-Directional Environmental Sensors

    Science.gov (United States)

    Manohara, Harish (Inventor); Del Castillo, Linda Y. (Inventor); Mojarradi, Mohammed M. (Inventor)

    2016-01-01

    Systems and methods in accordance with embodiments of the invention implement multi-directional environmental sensors. In one embodiment, a multi-directional environmental sensor includes: an inner conductive element that is substantially symmetrical about three orthogonal planes; an outer conductive element that is substantially symmetrical about three orthogonal planes; and a device that measures the electrical characteristics of the multi-directional environmental sensor, the device having a first terminal and a second terminal; where the inner conductive element is substantially enclosed within the outer conductive element; where the inner conductive element is electrically coupled to the first terminal of the device; and where the outer conductive element is electrically coupled to the second terminal of the device.

  7. Development of a small-sized generator of ozonated water using an electro-conductive diamond electrode.

    Science.gov (United States)

    Sekido, Kota; Kitaori, Noriyuki

    2008-12-01

    A small-sized generator of ozonated water was developed using an electro-conductive diamond. We studied the optimum conditions for producing ozonated water. As a result, we developed a small-sized generator of ozonated water driven by a dry-cell for use in the average household. This generator was easily able to produce ozonated water with an ozone concentration (over 4 mg/L) sufficient for disinfection. In addition, we verified the high disinfecting performance of the water produced in an actual hospital.

  8. Magnetoacoustic microscopic imaging of conductive objects and nanoparticles distribution

    Science.gov (United States)

    Liu, Siyu; Zhang, Ruochong; Luo, Yunqi; Zheng, Yuanjin

    2017-09-01

    Magnetoacoustic tomography has been demonstrated as a powerful and low-cost multi-wave imaging modality. However, due to limited spatial resolution and detection efficiency of magnetoacoustic signal, full potential of the magnetoacoustic imaging remains to be tapped. Here we report a high-resolution magnetoacoustic microscopy method, where magnetic stimulation is provided by a compact solenoid resonance coil connected with a matching network, and acoustic reception is realized by using a high-frequency focused ultrasound transducer. Scanning the magnetoacoustic microscopy system perpendicularly to the acoustic axis of the focused transducer would generate a two-dimensional microscopic image with acoustically determined lateral resolution. It is analyzed theoretically and demonstrated experimentally that magnetoacoustic generation in this microscopic system depends on the conductivity profile of conductive objects and localized distribution of superparamagnetic iron magnetic nanoparticles, based on two different but related implementations. The lateral resolution is characterized. Directional nature of magnetoacoustic vibration and imaging sensitivity for mapping magnetic nanoparticles are also discussed. The proposed microscopy system offers a high-resolution method that could potentially map intrinsic conductivity distribution in biological tissue and extraneous magnetic nanoparticles.

  9. Optimal design of permanent magnet flux switching generator for wind applications via artificial neural network and multi-objective particle swarm optimization hybrid approach

    International Nuclear Information System (INIS)

    Meo, Santolo; Zohoori, Alireza; Vahedi, Abolfazl

    2016-01-01

    Highlights: • A new optimal design of flux switching permanent magnet generator is developed. • A prototype is employed to validate numerical data used for optimization. • A novel hybrid multi-objective particle swarm optimization approach is proposed. • Optimization targets are weight, cost, voltage and its total harmonic distortion. • The hybrid approach preference is proved compared with other optimization methods. - Abstract: In this paper a new hybrid approach obtained combining a multi-objective particle swarm optimization and artificial neural network is proposed for the design optimization of a direct-drive permanent magnet flux switching generators for low power wind applications. The targets of the proposed multi-objective optimization are to reduce the costs and weight of the machine while maximizing the amplitude of the induced voltage as well as minimizing its total harmonic distortion. The permanent magnet width, the stator and rotor tooth width, the rotor teeth number and stator pole number of the machine define the search space for the optimization problem. Four supervised artificial neural networks are designed for modeling the complex relationships among the weight, the cost, the amplitude and the total harmonic distortion of the output voltage respect to the quantities of the search space. Finite element analysis is adopted to generate training dataset for the artificial neural networks. Finite element analysis based model is verified by experimental results with a 1.5 kW permanent magnet flux switching generator prototype suitable for renewable energy applications, having 6/19 stator poles/rotor teeth. Finally the effectiveness of the proposed hybrid procedure is compared with the results given by conventional multi-objective optimization algorithms. The obtained results show the soundness of the proposed multi objective optimization technique and its feasibility to be adopted as suitable methodology for optimal design of permanent

  10. Simulating secondary organic aerosol in a regional air quality model using the statistical oxidation model – Part 1: Assessing the influence of constrained multi-generational ageing

    Directory of Open Access Journals (Sweden)

    S. H. Jathar

    2016-02-01

    Full Text Available Multi-generational oxidation of volatile organic compound (VOC oxidation products can significantly alter the mass, chemical composition and properties of secondary organic aerosol (SOA compared to calculations that consider only the first few generations of oxidation reactions. However, the most commonly used state-of-the-science schemes in 3-D regional or global models that account for multi-generational oxidation (1 consider only functionalization reactions but do not consider fragmentation reactions, (2 have not been constrained to experimental data and (3 are added on top of existing parameterizations. The incomplete description of multi-generational oxidation in these models has the potential to bias source apportionment and control calculations for SOA. In this work, we used the statistical oxidation model (SOM of Cappa and Wilson (2012, constrained by experimental laboratory chamber data, to evaluate the regional implications of multi-generational oxidation considering both functionalization and fragmentation reactions. SOM was implemented into the regional University of California at Davis / California Institute of Technology (UCD/CIT air quality model and applied to air quality episodes in California and the eastern USA. The mass, composition and properties of SOA predicted using SOM were compared to SOA predictions generated by a traditional two-product model to fully investigate the impact of explicit and self-consistent accounting of multi-generational oxidation.Results show that SOA mass concentrations predicted by the UCD/CIT-SOM model are very similar to those predicted by a two-product model when both models use parameters that are derived from the same chamber data. Since the two-product model does not explicitly resolve multi-generational oxidation reactions, this finding suggests that the chamber data used to parameterize the models captures the majority of the SOA mass formation from multi-generational oxidation under

  11. Distributed Generation Planning using Peer Enhanced Multi-objective Teaching-Learning based Optimization in Distribution Networks

    Science.gov (United States)

    Selvam, Kayalvizhi; Vinod Kumar, D. M.; Siripuram, Ramakanth

    2017-04-01

    In this paper, an optimization technique called peer enhanced teaching learning based optimization (PeTLBO) algorithm is used in multi-objective problem domain. The PeTLBO algorithm is parameter less so it reduced the computational burden. The proposed peer enhanced multi-objective based TLBO (PeMOTLBO) algorithm has been utilized to find a set of non-dominated optimal solutions [distributed generation (DG) location and sizing in distribution network]. The objectives considered are: real power loss and the voltage deviation subjected to voltage limits and maximum penetration level of DG in distribution network. Since the DG considered is capable of injecting real and reactive power to the distribution network the power factor is considered as 0.85 lead. The proposed peer enhanced multi-objective optimization technique provides different trade-off solutions in order to find the best compromise solution a fuzzy set theory approach has been used. The effectiveness of this proposed PeMOTLBO is tested on IEEE 33-bus and Indian 85-bus distribution system. The performance is validated with Pareto fronts and two performance metrics (C-metric and S-metric) by comparing with robust multi-objective technique called non-dominated sorting genetic algorithm-II and also with the basic TLBO.

  12. Effects of Heat Input and Bead Generation Methods on Finite Element Analysis of Multi-Pass Welding Process

    Energy Technology Data Exchange (ETDEWEB)

    Park, Won Dong; Kim, Ji Hoon; Bahn, Chi Bum [Pusan National University, Busan (Korea, Republic of)

    2016-10-15

    Welding residual stresses are determined by various factors such as heat input, initial temperature of molten bead, heating time, cooling time, cooling conditions, and boundary conditions. In this study, a sensitivity analysis was performed to find the major factors and reasonable assumptions for simulation. Two-dimensional axisymmetric simulation was conducted by using commercial finite element analysis program ABAQUS, for multi-pass Alloy 82 welds in a 304 Stainless Steel and SA-105 Carbon Steel. The major object is to evaluate effects of the heat input methods and weld bead generation methods on the welding residual stress distribution. Totally four kinds of methods were compared. From the previous results, we could make the following conclusions. 1. Although there are non-negligible differences in HAZ depending on heat input method, welding residual stress distributions have roughly similar trends. However, it is needed to perform the more exact analysis to apply heat energy more carefully into the individual bead. 2. Residual stress distribution were similar for the two weld bead generation technique. However, overlapping was happened when element birth technique was applied. Effects of overlapping could not ignore as deformation increases. However, overlapping problem was avoided when quiet element technique was used. 3. Since existence of inactive bead elements, inaccurate weld residual stresses could be occurred in boundaries of previous and next weld elements in case of quiet element technique.

  13. AN INITIATIVE FOR CONSTRUCTION OF NEW-GENERATION LUNAR GLOBAL CONTROL NETWORK USING MULTI-MISSION DATA

    Directory of Open Access Journals (Sweden)

    K. Di

    2017-07-01

    Full Text Available A lunar global control network provides geodetic datum and control points for mapping of the lunar surface. The widely used Unified Lunar Control Network 2005 (ULCN2005 was built based on a combined photogrammetric solution of Clementine images acquired in 1994 and earlier photographic data. In this research, we propose an initiative for construction of a new-generation lunar global control network using multi-mission data newly acquired in the 21st century, which have much better resolution and precision than the old data acquired in the last century. The new control network will be based on a combined photogrammetric solution of an extended global image and laser altimetry network. The five lunar laser ranging retro-reflectors, which can be identified in LROC NAC images and have cm level 3D position accuracy, will be used as absolute control points in the least squares photogrammetric adjustment. Recently, a new radio total phase ranging method has been developed and used for high-precision positioning of Chang’e-3 lander; this shall offer a new absolute control point. Systematic methods and key techniques will be developed or enhanced, including rigorous and generic geometric modeling of orbital images, multi-scale feature extraction and matching among heterogeneous multi-mission remote sensing data, optimal selection of images at areas of multiple image coverages, and large-scale adjustment computation, etc. Based on the high-resolution new datasets and developed new techniques, the new generation of global control network is expected to have much higher accuracy and point density than the ULCN2005.

  14. [A Multi-arm Placebo-controlled Study with Glutamic Acid Conducted in Rostock in 1953/1954].

    Science.gov (United States)

    Häßler, Frank; Weirich, Steffen

    2017-09-01

    A Multi-arm Placebo-controlled Study with Glutamic Acid Conducted in Rostock in 1953/1954 Glutamic acid was commonly used in the treatment of intellectually disabled children in the 50s. Koch reported first results of an observation of 140 children treated with glutamic acid in 1952. In this line is the multi-arm placebo-controlled study reported here. The original study protocols were available. 58 children with speech problems who attending a school of special needs received glutamic acid, or vitamin B, or St.-John's-wort. The effect of glutamic acid was in few cases an improvement of attention. On the other hand restlessness and stutter increased. The majority of all reported a weight loss. The treatment with vitamin B showed a positive effect concerning concentration. The treatment with St.-John's wort was stopped caused by headache and vomiting in eight of nine cases. The results of the study reported here are unpublished. The reason may be that until the 60s the effects of glutamic acid in the treatment of intellectually disabled children were in generally overestimated.

  15. Energetic and exergoeconomic assessment of a multi-generation energy system based on indirect use of geothermal energy

    International Nuclear Information System (INIS)

    Akrami, Ehsan; Chitsaz, Ata; Nami, Hossein; Mahmoudi, S.M.S.

    2017-01-01

    In this paper, a geothermal based multi-generation energy system, including organic Rankine cycle, domestic water heater, absorption refrigeration cycle and proton exchange membrane electrolyzer, is developed to generate electricity, heating, cooling and hydrogen. For this purpose, energetic, exergetic and exergoeconomic analysis are undertaken upon proposed system. Also, the effects of some important variables, i.e. geothermal water temperature, turbine inlet temperature and pressure, generator temperature, geothermal water mass flow rate and electrolyzer current density on the several parameters such as energy and exergy efficiencies of the proposed system, heating and cooling load, net electrical output power, hydrogen production, unit cost of each system products and total unit cost of the products are investigated. For specified conditions, the results show that energy and exergy efficiencies of the proposed multi-generation system are calculated about 34.98% and 49.17%, respectively. The highest and lowest total unit cost of the products estimated approximately 23.18 and 22.73 $/GJ, respectively, by considering that geothermal water temperature increases from 185 °C to 215 °C. - Highlights: • A multigeneration energy system based on geothermal energy is developed. • The energetic, exergetic and exergoeconomic analysis are undertaken upon proposed system. • The influences of several significant parameters are investigated. • The energy and exergy efficiencies of the entire system are calculated around 34.98% and 49.17%.

  16. CER Hub: An informatics platform for conducting comparative effectiveness research using multi-institutional, heterogeneous, electronic clinical data.

    Science.gov (United States)

    Hazlehurst, Brian L; Kurtz, Stephen E; Masica, Andrew; Stevens, Victor J; McBurnie, Mary Ann; Puro, Jon E; Vijayadeva, Vinutha; Au, David H; Brannon, Elissa D; Sittig, Dean F

    2015-10-01

    Comparative effectiveness research (CER) requires the capture and analysis of data from disparate sources, often from a variety of institutions with diverse electronic health record (EHR) implementations. In this paper we describe the CER Hub, a web-based informatics platform for developing and conducting research studies that combine comprehensive electronic clinical data from multiple health care organizations. The CER Hub platform implements a data processing pipeline that employs informatics standards for data representation and web-based tools for developing study-specific data processing applications, providing standardized access to the patient-centric electronic health record (EHR) across organizations. The CER Hub is being used to conduct two CER studies utilizing data from six geographically distributed and demographically diverse health systems. These foundational studies address the effectiveness of medications for controlling asthma and the effectiveness of smoking cessation services delivered in primary care. The CER Hub includes four key capabilities: the ability to process and analyze both free-text and coded clinical data in the EHR; a data processing environment supported by distributed data and study governance processes; a clinical data-interchange format for facilitating standardized extraction of clinical data from EHRs; and a library of shareable clinical data processing applications. CER requires coordinated and scalable methods for extracting, aggregating, and analyzing complex, multi-institutional clinical data. By offering a range of informatics tools integrated into a framework for conducting studies using EHR data, the CER Hub provides a solution to the challenges of multi-institutional research using electronic medical record data. Copyright © 2015. Published by Elsevier Ireland Ltd.

  17. Radiation Environments and Exposure Considerations for the Multi-Mission Radioisotope Thermoelectric Generator

    International Nuclear Information System (INIS)

    Kelly, William M.; Low, Nora M.; Zillmer, Andrew; Johnson, Gregory A.; Normand, Eugene

    2006-01-01

    The Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) is the next generation (RTG) being developed by DOE to provide reliable, long-life electric power for NASA's planetary exploration programs. The MMRTG is being developed by Pratt and Whitney Rocketdyne and Teledyne Energy Systems Incorporated (TESI) for use on currently planned and projected flyby, orbital and planet landing missions. This is a significant departure from the design philosophy of the past which was to match specific mission requirements to RTG design capabilities. Undefined mission requirements provide a challenge to system designers by forcing them to put a design envelope around 'all possible missions'. These multi-mission requirements include internal and external radiation sources. Internal sources include the particles ejected by decaying Pu-238 and its daughters plus particles resulting from the interaction of these particles with other MMRTG materials. External sources include the full spectrum of charged particle radiation surrounding planets with magnetic fields and the surfaces of extraterrestrial objects not shielded by magnetic fields. The paper presents the results of investigations into the environments outlined above and the impact of radiation exposure on potential materials to be used on MMRTG and ground support personnel. Mission requirements were also reviewed to evaluate total integrated dose and to project potential shielding requirements for materials. Much of the information on mission shielding requirements was provided by NASA's Jet Propulsion Laboratory. The primary result is an ionizing radiation design curve which indicates the limits to which a particular mission can take the MMRTG in terms of ionizing radiation exposure. Estimates of personnel radiation exposure during ground handling are also provided

  18. Short term hydroelectric power system scheduling with wind turbine generators using the multi-pass iteration particle swarm optimization approach

    International Nuclear Information System (INIS)

    Lee, T.-Y.

    2008-01-01

    This paper uses multi-pass iteration particle swarm optimization (MIPSO) to solve short term hydroelectric generation scheduling of a power system with wind turbine generators. MIPSO is a new algorithm for solving nonlinear optimal scheduling problems. A new index called iteration best (IB) is incorporated into particle swarm optimization (PSO) to improve solution quality. The concept of multi-pass dynamic programming is applied to modify PSO further and improve computation efficiency. The feasible operational regions of the hydro units and pumped storage plants over the whole scheduling time range must be determined before applying MIPSO to the problem. Wind turbine power generation then shaves the power system load curves. Next, MIPSO calculates hydroelectric generation scheduling. It begins with a coarse time stage and searching space and refines the time interval between two time stages and the search spacing pass by pass (iteration). With the cooperation of agents called particles, the near optimal solution of the scheduling problem can be effectively reached. The effects of wind speed uncertainty were also considered in this paper. The feasibility of the new algorithm is demonstrated by a numerical example, and MIPSO solution quality and computation efficiency are compared to those of other algorithms

  19. Risk-averse portfolio selection of renewable electricity generator investments in Brazil: An optimised multi-market commercialisation strategy

    International Nuclear Information System (INIS)

    Maier, Sebastian; Street, Alexandre; McKinnon, Ken

    2016-01-01

    Investment decisions in renewable energy sources such as small hydro, wind power, biomass and solar are frequently made in the context of enormous uncertainty surrounding both intermittent generation and the highly volatile electricity spot prices that are used for clearing of trades. This paper presents a new portfolio-based approach for selecting long-term investments in small-scale renewable energy projects and matching contracts for the sale of the resulting electricity. Using this approach, we have formulated a stochastic optimisation model that maximises a holding company's risk-averse measure of value. Using an illustrative example representative of investment decisions within the Brazilian electricity system, we investigate the sensitivity of the optimised portfolio composition and commercialisation strategy to contract prices in the free contracting environment and to the decision maker's attitude towards risk. The numerical results demonstrate it is possible to reduce significantly financial risks, such as the price-quantity risk, not only by exploiting the complementarity of the considered renewable sources generation profiles, but also by selecting the optimal mix of commercialisation contracts from different markets. We find that the multi-market strategy generally results in appreciably higher optimal value than single-market strategies and can be applied to a wide range of renewable generators and contracts. - Highlights: • Gives a portfolio-based multi-market, multi-asset approach to renewable investment. • Details how to model currently used contract types in each of the Brazilian markets. • Presents a test case using realistic contract and real renewable data from Brazil. • Shows that the approach controls financial risks and boosts optimal values. • Explains how relative contract prices and attitude to risk affect optimal decisions.

  20. Analysis of wind energy generation possibilities with various rotor types at disadvantageous wind condition zones

    Science.gov (United States)

    Bieniek, Andrzej

    2017-10-01

    The paper describe possibilities of energy generation using various rotor types but especially with multi-blade wind engine operates in the areas with unfavourable wind condition. The paper presents also wind energy conversion estimation results presented based on proposed solution of multi-blade wind turbine of outer diameter of 4 m. Based on the wind distribution histogram from the disadvantage wind condition zones (city of Basel) and taking into account design and estimated operating indexes of the considered wind engine rotor an annual energy generation was estimated. Also theoretical energy generation using various types of wind turbines operates at disadvantage wind conditions zones were estimated and compared. The conducted analysis shows that introduction of multi-blade wind rotor instead of the most popular 3- blades or vertical axis rotors results of about 5% better energy generation. Simultaneously there are energy production also at very disadvantages wind condition at wind speed lower then 4 m s-1. Based on considered construction of multi-blade wind engine the rise of rotor mounting height from 10 to 30 m results with more then 300 % better results in terms of electric energy generation.

  1. Analysis of wind energy generation possibilities with various rotor types at disadvantageous wind condition zones

    Directory of Open Access Journals (Sweden)

    Bieniek Andrzej

    2017-01-01

    Full Text Available The paper describe possibilities of energy generation using various rotor types but especially with multi-blade wind engine operates in the areas with unfavourable wind condition. The paper presents also wind energy conversion estimation results presented based on proposed solution of multi-blade wind turbine of outer diameter of 4 m. Based on the wind distribution histogram from the disadvantage wind condition zones (city of Basel and taking into account design and estimated operating indexes of the considered wind engine rotor an annual energy generation was estimated. Also theoretical energy generation using various types of wind turbines operates at disadvantage wind conditions zones were estimated and compared. The conducted analysis shows that introduction of multi-blade wind rotor instead of the most popular 3- blades or vertical axis rotors results of about 5% better energy generation. Simultaneously there are energy production also at very disadvantages wind condition at wind speed lower then 4 ms-1. Based on considered construction of multi-blade wind engine the rise of rotor mounting height from 10 to 30 m results with more then 300 % better results in terms of electric energy generation.

  2. Influence of water conductivity on shock waves generated by underwater electrical wire explosion

    Science.gov (United States)

    Liu, Ben; Wang, Deguo; Guo, Yanbao

    2018-01-01

    The new application of electrical explosion of wire (EEW) used in petroleum industry is to enhance oil recovery (EOR). Because of the complex environment underground, the effect of underground water conductivity on EEW should be considered. This work describes the effect of water conductivities on discharge current, voltage and shock waves. It was found that the effect of water conductivity contains two parts. One is the shunt effect of saline water, which can be considered as a parallel load with the copper wire between the electrodes connected to the discharge circuit. The peak pressure of shock waves are gradually decrease with the increase of water conductivity. The other is the current loss through saline water directly to the ground ends without flowing through the electrodes. The shunt effect is the main factor affecting the wire discharge process. As the charging voltage increased, the energy loss caused by these two parts are all reduced. These indicate that increasing the charging voltage to a certain value will increase the energy efficiency to generate a more powerful shock waves in conductive water.

  3. Study of multi-generational effects of a chronic exposure to ionizing radiations at a model organism: the nematode Caenorhabditis elegans

    International Nuclear Information System (INIS)

    Buisset-Goussen, Adeline

    2014-01-01

    The environmental risk assessment of chronic exposure to ionizing radiation (natural and ubiquitous phenomenon enhanced by human activities) has become a major concern. Few studies relating to chronic exposure over several generations - essential knowledge to better understand the disruption caused by ionizing radiation and its possible consequences on the population - exist. In addition, it has become necessary to understand the mechanisms of disturbances related to ionizing radiation at the molecular and cellular level. Without this mechanistic understanding, it is difficult to extrapolate the effects observed between the different levels of biological organization and between different species. The aim of this PhD was to study the multi-generational effects of chronic gamma radiation in an integrated manner (to the life history traits from the subcellular mechanisms) in a model organism, the nematode Caenorhabditis elegans. A two-step strategy was implemented. First, studying the effects of chronic gamma radiation on the life history traits of C. elegans was performed. The objective of this experiment was to test the hypothesis of an increase of the sensitivity according generations. For that, three generations have been exposed to different dose rates. In parallel, two generations have been placed in 'control' environment after parental exposure to test a possible transmission of maternal effects. The second part of this thesis aimed to characterize the different subcellular mechanisms that could explain the observed effects on the life history traits after multi-generational exposure. The results showed that (i) the cumulative number of larvae was the most sensitive endpoint to gamma radiation, (ii) an increase in radiosensitivity was observed over three exposed generations and (iii) the effects of the parental generation were transmitted to the non-exposed generations. An increase in apoptosis, a reduction in the stock of sperm, and to a lesser

  4. Multi-objective optimization of Stirling engine using Finite Physical Dimensions Thermodynamics (FPDT) method

    International Nuclear Information System (INIS)

    Li, Ruijie; Grosu, Lavinia; Queiros-Conde, Diogo

    2016-01-01

    Highlights: • A gamma Stirling engine has been optimized using FPDT method by multi-objective criteria. • Genetic algorithm and decision making methods were used to get Pareto frontier and optimum points. • It shows: total thermal conductance, hot temperature, stroke and diameter ratios can be improved. - Abstract: In this paper, a solar energy powered gamma type SE has been optimized using Finite Physical Dimensions Thermodynamics (FPDT) method by multi-objective criteria. Genetic algorithm was used to get the Pareto frontier, and optimum points were obtained using the decision making methods of LINMAP and TOPSIS. The optimization results have been compared with those obtained using the ecological method. It was shown that the multi-objective optimization in this paper has a better balance among the optimizing criteria (maximum mechanical power, maximum thermal efficiency and minimum entropy generation flow). The effects of the hot source temperature and the total thermal conductance of the engine on the Pareto frontier have been also studied. This sensibility study shows that an increase in the hot reservoir temperature can increase the output mechanical power, the thermal efficiency of the engine, but also the entropy generation rate. In addition to this, an increase of the total thermal conductance of the engine can strongly increase the output mechanical power and only slightly increase the thermal efficiency. These results allow us to improve the engine performance after some modifications as geometrical dimensions (diameter, stroke, heat exchange surface, etc.) and physical parameters (temperature, thermal conductivity).

  5. Enhanced electrical conductivity and hardness of silver-nickel composites by silver-coated multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Lee, Dongmok; Sim, Jeonghyun; Baik, Seunghyun; Kim, Wonyoung; Moon, Chuldong; Cho, Wookdong

    2015-01-01

    We investigated electrical conductivity and Vickers hardness of Ag- and Ni-based composites prepared by powder metallurgy involving spark plasma sintering. The starting composition was Ag:Ni = 61:39 vol%, which provided an electrical conductivity of 3.30 × 10"5 S cm"−"1 and a hardness of 1.27 GPa. The addition of bare multi-walled carbon nanotubes (MWNTs, 1.45 vol%) increased hardness (1.31 GPa) but decreased electrical conductivity (2.99 × 10"5 S cm"−"1) and carrier mobility (11 cm"2 V"−"1 s"−"1) due to the formation of Ni_3C in the interface between the MWNTs and Ni during spark plasma sintering. The formation of Ni_3C was prevented by coating the surface of the nanotubes with Ag (nAgMWNTs), concomitantly increasing electrical conductivity (3.43 × 10"5 S cm"−"1) and hardness (1.37 GPa) of the sintered specimen (Ag:Ni:nAgMWNTs = 59.55:39:1.45 vol%). The electrical contact switching time (133 357) was also increased by 30%, demonstrating excellent feasibility as electrical contact materials for electric power industries. (paper)

  6. Multi-Unit Aspects of the Pickering Generating Station

    Energy Technology Data Exchange (ETDEWEB)

    Morison, W. G. [Atomic Energy of Canada Ltd, Sheridan Park, ON (Canada)

    1968-04-15

    The Pickering nuclear generating station is located on the north shore of Lake Ontario, about 20 miles east of the city of Toronto, Canada. The station has been planned and laid out on an eight-unit station, four units of which have now been authorized for construction. Each of these four units consists of a single heavy-water moderated and cooled CANDU-type reactor and auxiliaries coupled to a single tandem compound turbine generator with a net output of approximately 500 MW(e). The units are identical and are scheduled to come into operation at intervals of one year from 1970 to 1973. The station has been planned with central facilities for: administration maintenance laboratories, stores, change rooms, decontamination and waste management services. A common control centre, cooling water intake and discharge system, and spent fuel storage bay for four units has been arranged. A feature of the multi-unit station is a common containment system. Cost savings in building a number of identical units on the same site result from a single exclusion area, shared engineering costs, equipment purchase contracts for four identical components, and efficient use of construction plant. Operating cost savings are anticipated in the use of a common operating and maintenance staff and spare parts inventory. The plant has been arranged to minimize problems of operating, commissioning and constructing units at the same time on the same site. The layout and construction sequence have been arranged so that the first unit can be commissioned and operated with little or no interference from the construction forces working on succeeding units. During the construction phase barriers will be erected in the common control centre between operating control equipment and that being installed. Operations and construction personnel will enter the plant by separate routes and work in areas separated by physical barriers. (author)

  7. Transient heat conduction in multi-layer walls: An efficient strategy for Laplace's method

    Energy Technology Data Exchange (ETDEWEB)

    Maestre, Ismael R.; Cubillas, Paloma R. [Escuela Politecnica Superior de Algeciras, University of Cadiz, Algeciras (Spain); Perez-Lombard, Luis [Escuela Superior de Ingenieros, University of Seville (Spain)

    2010-04-15

    Enhancing load calculation tools into building simulation programs requires an in-depth revision and fine tuning of the load calculation assumptions prior to the addition of the HVAC system modelling routines. It is of special interest the analysis of transient heat conduction through multi-layer walls where, in order to improve the coupling between the passive elements of the building and the HVAC systems, an improvement of the time resolution in the calculation becomes critical. Several methods have been historically used, although recently Laplace's method has been displaced by the State Space method. This paper proposes a new strategy for fine time resolution on the calculation of the response factors through Laplace's method considering a comparison with the performance of the State Space method when used to calculate conduction transfer functions. Our analysis shows that in order to achieve similar accuracy with both approaches, the State Space method requires significant additional computational time. (author)

  8. A test sheet generating algorithm based on intelligent genetic algorithm and hierarchical planning

    Science.gov (United States)

    Gu, Peipei; Niu, Zhendong; Chen, Xuting; Chen, Wei

    2013-03-01

    In recent years, computer-based testing has become an effective method to evaluate students' overall learning progress so that appropriate guiding strategies can be recommended. Research has been done to develop intelligent test assembling systems which can automatically generate test sheets based on given parameters of test items. A good multisubject test sheet depends on not only the quality of the test items but also the construction of the sheet. Effective and efficient construction of test sheets according to multiple subjects and criteria is a challenging problem. In this paper, a multi-subject test sheet generation problem is formulated and a test sheet generating approach based on intelligent genetic algorithm and hierarchical planning (GAHP) is proposed to tackle this problem. The proposed approach utilizes hierarchical planning to simplify the multi-subject testing problem and adopts genetic algorithm to process the layered criteria, enabling the construction of good test sheets according to multiple test item requirements. Experiments are conducted and the results show that the proposed approach is capable of effectively generating multi-subject test sheets that meet specified requirements and achieve good performance.

  9. Electrical conductivity and electromagnetic interference shielding of epoxy nanocomposite foams containing functionalized multi-wall carbon nanotubes

    Science.gov (United States)

    Li, Jiantong; Zhang, Guangcheng; Zhang, Hongming; Fan, Xun; Zhou, Lisheng; Shang, Zhengyang; Shi, Xuetao

    2018-01-01

    Epoxy/functionalized multi-wall carbon nanotube (EP/F-MWCNT) microcellular foams were fabricated through a supercritical CO2 (scCO2) foaming method. MWCNTs with carboxylation treatment were disentangled by using alpha-zirconium phosphate (ZrP) assisting dispersion method and functionalized with sulfanilamide. The F-MWCNTs were redispersed in acetone for mixing with epoxy resins to prepare nanocomposites. It was found that the dispersion of MWCNTs could be improved, thus heterogeneous nucleation effect of F-MWCNTs took place effectively during the foaming process, resulting in the formation of microcellular structure with larger cell density and smaller cell size. The volume conductivity and electromagnetic interference shielding performance of foamed EP/F-MWCNT nanocomposites were studied. When the F-MWCNT addition was 5 wt%, the conductivity of the foamed EP/F-MWCNT nanocomposites was 3.02 × 10-4 S/cm and the EMI shielding effectiveness (SE) reached 20.5 dB, significantly higher than the corresponding results of nanocomposite counterparts, indicating that introducing microcellular structure in EP/F-MWCNT nanocomposites would beneficial to improve their electrical conductivity and electromagnetic interference shielding performance.

  10. Design, simulation and testing of a novel radial multi-pole multi-layer magnetorheological brake

    Science.gov (United States)

    Wu, Jie; Li, Hua; Jiang, Xuezheng; Yao, Jin

    2018-02-01

    This paper deals with design, simulation and experimental testing of a novel radial multi-pole multi-layer magnetorheological (MR) brake. This MR brake has an innovative structural design with superposition principle of two magnetic fields generated by the inner coils and the outer coils. The MR brake has several media layers of magnetorheological (MR) fluid located between the inner coils and the outer coils, and it can provide higher torque and higher torque density than conventional single-disk or multi-disk or multi-pole single-layer MR brakes can. In this paper, a brief introduction to the structure of the proposed MR brake was given first. Then, theoretical analysis of the magnetic circuit and the braking torque was conducted. In addition, a 3D electromagnetic model of the MR brake was developed to simulate and examine the magnetic flux intensity and corresponding braking torque. A prototype of the brake was fabricated and several tests were carried out to validate its torque capacity. The results show that the proposed MR brake can produce a maximum braking torque of 133 N m and achieve a high torque density of 25.0 kN m-2, a high torque range of 42 and a high torque-to-power ratio of 0.95 N m W-1.

  11. MHD nanofluid free convection and entropy generation in porous enclosures with different conductivity ratios

    Science.gov (United States)

    Ghasemi, Kasra; Siavashi, Majid

    2017-11-01

    MHD natural convection of Cu-water nanofluid in a square porous enclosure is investigated using a parallel LBM code, considering temperature dependence of viscosity and viscous dissipation. Effects of nanofluid concentration (φ = 0 - 0.12), Rayleigh (Ra =103 -106), Hartmann (Ha = 0-20) and porous-fluid thermal conductivity ratio (K∗ = 1-70) on heat transfer and entropy generation are investigated. It is shown that K∗ is a very important parameter, and porous media with low K∗ numbers can confine convection effects, but by increasing K∗ both conduction and convection effects can substantially improve. Also, magnetic field always has negative impact on Nu, however this impact can be controlled by φ and K∗. A magnetic instability has also observed in Ra = 104, and Nu exhibits a sinusoidal variation with Ha. It is proved that, depending on K∗, Ra and Ha values, use of nanofluid with porous media to enhance heat transfer can be either beneficial or detrimental. Also, for given K∗, Ra and Ha numbers an optimal φ exists to improve heat transfer. Finally, entropy generation study performed and results state that in low and high Ra values the thermal and frictional entropy generation are respectively dominant, while for moderate Ra they have the same order of magnitude.

  12. Dual-acting of Hybrid Compounds - A New Dawn in the Discovery of Multi-target Drugs: Lead Generation Approaches.

    Science.gov (United States)

    Abdolmaleki, Azizeh; Ghasemi, Jahan B

    2017-01-01

    Finding high quality beginning compounds is a critical job at the start of the lead generation stage for multi-target drug discovery (MTDD). Designing hybrid compounds as selective multitarget chemical entity is a challenge, opportunity, and new idea to better act against specific multiple targets. One hybrid molecule is formed by two (or more) pharmacophore group's participation. So, these new compounds often exhibit two or more activities going about as multi-target drugs (mtdrugs) and may have superior safety or efficacy. Application of integrating a range of information and sophisticated new in silico, bioinformatics, structural biology, pharmacogenomics methods may be useful to discover/design, and synthesis of the new hybrid molecules. In this regard, many rational and screening approaches have followed by medicinal chemists for the lead generation in MTDD. Here, we review some popular lead generation approaches that have been used for designing multiple ligands (DMLs). This paper focuses on dual- acting chemical entities that incorporate a part of two drugs or bioactive compounds to compose hybrid molecules. Also, it presents some of key concepts and limitations/strengths of lead generation methods by comparing combination framework method with screening approaches. Besides, a number of examples to represent applications of hybrid molecules in the drug discovery are included. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  13. Improvement of ISI techniques by multi-frequency eddy current testing method for steam generator tube in PWR plant

    International Nuclear Information System (INIS)

    Endo, Takashi; Kamimura, Takeo; Nishihara, Masatoshi; Araki, Yasuo; Fukui, Shigetaka.

    1982-05-01

    Eddy current flaw detection techniques are applied to the in-service inspection (ISI) of steam generator tubes in pressurized water reactors (PWR) plant. To improve the reliability and operating efficiency of the plants, efforts are being made to develop eddy current testing methods of various kinds. Multi-frequency eddy current testing method, one of new method, has recently been applied to actual heat exchanger tubes, contributing to the improvement of the detectability and signal evaluation of the ISI. The outline of multi-frequency eddy current testing method and its effects on the improvement of flaw detecting and signal evaluation accuracy are described. (author)

  14. Incorporating a multi-criteria decision procedure into the combined dynamic programming/production simulation algorithm for generation expansion planning

    International Nuclear Information System (INIS)

    Yang, H.T.; Chen, S.L.

    1989-01-01

    A multi-objective optimization approach to generation expansion planning is presented. The approach is designed by adding a new multi-criteria decision (MCD) procedure to the conventional algorithm which combines dynamic programming with production simulation method. The MCD procedure can help decision makers weight the relative importance of multiple attributes associated with the decision alternatives, and find the near-best compromise solution efficiently at each optimization step of the conventional algorithm. Practical application of proposed approach to feasibility evaluation of the fourth nuclear power plant of Tawian is also presented, demonstrating the effectiveness and limitations of the approach

  15. Generation of tunable chain of three-dimensional optical bottle beams via focused multi-ring hollow Gaussian beam.

    Science.gov (United States)

    Philip, Geo M; Viswanathan, Nirmal K

    2010-11-01

    We report here the generation of a chain of three-dimensional (3-D) optical bottle beams by focusing a π-phase shifted multi-ring hollow Gaussian beam (HGB) using a lens with spherical aberration. The rings of the HGB of suitable radial (k(r)) and axial (k(z)) wave vectors are generated using a double-negative axicon chemically etched in the optical fiber tips. Moving the lens position with respect to the fiber tip results in variation of the semi-angle of the cones of wave vectors of the HGBs and their diameter, using which we demonstrate tunability in the size and the periodicity of the 3-D optical bottle beams over a wide range, from micrometers to millimeters. The propagation characteristics of the beams resulting from focusing of single- and multi-ring HGBs and resulting in a quasi-non-diffracting beam and a chain of 3-D optical bottle beams, respectively, are simulated using only the input beam parameters and are found to agree well with experimental results.

  16. Electrode Conduction Processes Segmented Electrode-Insulator Ratio Effects in MHD Power Generation Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Pain, H. J.; Fearn, D. G.; Distefano, E. [Imperial College. London (United Kingdom)

    1966-10-15

    (a) Electrode conduction processes have been investigated using a plasma produced in an electromagnetic shock tube operating with argon at 70 {mu}mHg pressure. Complete voltage-current characteristics were obtained by the variation of load and applied voltage. These indicated the existence of two conduction regimes with a complex transition region. In the first regime the current, controlled by ion mobility, rose linearly with voltage to saturate between 10 mA and 1 A depending on conditions. Electrode contamination was significant. The second regime involved large currents controlled by electron mobility and emission from the cathode. The current again increased linearly with voltage and reached 200 A. Observation of induced voltages in transverse magnetic fields and of plasma deceleration in non-uniform fields showed that in the electromagnetic shock tube the plasma was heated predominantly by the driver discharge. Its conductivity was calculated using properties measured by a Langmuir double probe. In both regimes the plasma conductivity was also found from the gradient of the voltage current characteristics using experimental electric field fringing factors and the experimental values were compared with theory. (b) Larger-scale experiments used a combustion-driven shock tube where argon plasma flow, magnetic field and induced current flow were mutually orthogonal. The supersonic flow velocity and thermodynamic parameters of the plasma were accurately known. The electrode channel consisted of a segmented system of 12 electrode pairs with an electrode insulator ratio ranging from 1 to 21, with electrode plus insulator length remaining constant, and with maximum Hall parameter values of unity. Different electrode load combinations (Faraday and Hall generators) have been studied in measuring the power generated and the flow of longitudinal currents between adjacent electrodes. A maximum power of 0,8 MW was obtained, the power output decreasing inversely with the

  17. Electrode Conduction Processes Segmented Electrode-Insulator Ratio Effects in MHD Power Generation Experiments

    International Nuclear Information System (INIS)

    Pain, H.J.; Fearn, D.G.; Distefano, E.

    1966-01-01

    (a) Electrode conduction processes have been investigated using a plasma produced in an electromagnetic shock tube operating with argon at 70 μmHg pressure. Complete voltage-current characteristics were obtained by the variation of load and applied voltage. These indicated the existence of two conduction regimes with a complex transition region. In the first regime the current, controlled by ion mobility, rose linearly with voltage to saturate between 10 mA and 1 A depending on conditions. Electrode contamination was significant. The second regime involved large currents controlled by electron mobility and emission from the cathode. The current again increased linearly with voltage and reached 200 A. Observation of induced voltages in transverse magnetic fields and of plasma deceleration in non-uniform fields showed that in the electromagnetic shock tube the plasma was heated predominantly by the driver discharge. Its conductivity was calculated using properties measured by a Langmuir double probe. In both regimes the plasma conductivity was also found from the gradient of the voltage current characteristics using experimental electric field fringing factors and the experimental values were compared with theory. (b) Larger-scale experiments used a combustion-driven shock tube where argon plasma flow, magnetic field and induced current flow were mutually orthogonal. The supersonic flow velocity and thermodynamic parameters of the plasma were accurately known. The electrode channel consisted of a segmented system of 12 electrode pairs with an electrode insulator ratio ranging from 1 to 21, with electrode plus insulator length remaining constant, and with maximum Hall parameter values of unity. Different electrode load combinations (Faraday and Hall generators) have been studied in measuring the power generated and the flow of longitudinal currents between adjacent electrodes. A maximum power of 0,8 MW was obtained, the power output decreasing inversely with the

  18. Multi-stage fuzzy PID power system automatic generation controller in deregulated environments

    International Nuclear Information System (INIS)

    Shayeghi, H.; Shayanfar, H.A.; Jalili, A.

    2006-01-01

    In this paper, a multi-stage fuzzy proportional integral derivative (PID) type controller is proposed to solve the automatic generation control (AGC) problem in a deregulated power system that operates under deregulation based on the bilateral policy scheme. In each control area, the effects of the possible contracts are treated as a set of new input signals in a modified traditional dynamical model. The multi-stage controller uses the fuzzy switch to blend a proportional derivative (PD) fuzzy logic controller with an integral fuzzy logic input. The proposed controller operates on fuzzy values passing the consequence of a prior stage on to the next stage as fact. The salient advantage of this strategy is its high insensitivity to large load changes and disturbances in the presence of plant parameter variations and system nonlinearities. This newly developed strategy leads to a flexible controller with simple structure that is easy to implement, and therefore, it can be useful for the real world power systems. The proposed method is tested on a three area power system with different contracted scenarios under various operating conditions. The results of the proposed controller are compared with those of the classical fuzzy PID type controller and classical PID controller through some performance indices to illustrate its robust performance

  19. Multi-generational effects of rice harboring Bph15 on brown planthopper, Nilaparvata lugens.

    Science.gov (United States)

    Li, Jie; Shang, Keke; Liu, Jia; Jiang, Tingru; Hu, Dingbang; Hua, Hongxia

    2014-02-01

    The brown planthopper (BPH), Nilaparvata lugens, is one of the most devastating rice pests in Asia. Resistant cultivars are an effective way of managing BPH. Bph15 is a BPH resistance gene and has been introgressed into rice variety Minghui 63 (MH63). The multi-generational effects of rice line MH63::15 (harboring Bph15) on BPH were investigated and compared with its parental line MH63. U-test analysis indicated that, over seven generations, the developmental duration of BPH nymphs was significantly prolonged by MH63::15. The results of a two-way analysis indicated that, over seven generations, MH63::15 had significant negative effects on the hatchability, emergence rate, copulation rate, weight of adults and fecundity of BPH, but no significant effects on the survival rate of nymphs or female ratio of BPH. In addition, the development of ovary was significantly retarded by MH63::15, and the expression of oogenesis genes were either down-regulated (three genes) or up-regulated (one genes) by MH63::15 compared with MH63. After being reared continuously on MH63::15 for seven generations, most of the life parameters of BPH were negatively affected by MH63::15, especially fecundity and ovary development. These results indicate that MH63::15 rice has potential for use in the control of BPH. © 2013 Society of Chemical Industry.

  20. The experimental investigation on the performance of a low temperature waste heat-driven multi-bed desiccant dehumidifier (MBDD) and minimization of entropy generation

    KAUST Repository

    Myat, Aung; Thu, Kyaw; Ng, K. C.

    2012-01-01

    We present the experimental investigation on the performance of multi-bed desiccant dehumidification system (MBDD) using a thermodynamic framework with an entropy generation analysis. The cyclic steady state performance of adsorption-desorption processes at the assorted heat source temperatures, and typical ambient humidity conditions was carried out. MBDD unit uses type-RD silica gel pore surface area with of 720 m 2/g. It has a nominal diameter range of 0.4 to 0. 7 mm. The key advantages of MBDD are: (i) it has no moving parts rendering less maintenance, (ii) energy-efficient means of dehumidification by adsorption process with low temperature heat source as compared to the conventional methods, (iii) although it is a pecked bed desiccant, a laminar chamber is employed by arranging the V-shaped configuration of heat exchangers and (iv) it is environmental friendly with the low-carbon footprint. Entropy generation analysis was performed at the assorted heat source temperatures to investigate the performance of MBDD. By conducting the entropy minimization, it is now able to locate the optimal operating conditions of the system while the specific entropy generation is found to be minimal. This analysis shows that the minimization of entropy generation in the dehumidification cycle leads to the maximization of COP in the MBDD and thus, higher delivery of useful effects at the same input resources. © 2011 Elsevier Ltd. All rights reserved.

  1. The experimental investigation on the performance of a low temperature waste heat-driven multi-bed desiccant dehumidifier (MBDD) and minimization of entropy generation

    KAUST Repository

    Myat, Aung

    2012-06-01

    We present the experimental investigation on the performance of multi-bed desiccant dehumidification system (MBDD) using a thermodynamic framework with an entropy generation analysis. The cyclic steady state performance of adsorption-desorption processes at the assorted heat source temperatures, and typical ambient humidity conditions was carried out. MBDD unit uses type-RD silica gel pore surface area with of 720 m 2/g. It has a nominal diameter range of 0.4 to 0. 7 mm. The key advantages of MBDD are: (i) it has no moving parts rendering less maintenance, (ii) energy-efficient means of dehumidification by adsorption process with low temperature heat source as compared to the conventional methods, (iii) although it is a pecked bed desiccant, a laminar chamber is employed by arranging the V-shaped configuration of heat exchangers and (iv) it is environmental friendly with the low-carbon footprint. Entropy generation analysis was performed at the assorted heat source temperatures to investigate the performance of MBDD. By conducting the entropy minimization, it is now able to locate the optimal operating conditions of the system while the specific entropy generation is found to be minimal. This analysis shows that the minimization of entropy generation in the dehumidification cycle leads to the maximization of COP in the MBDD and thus, higher delivery of useful effects at the same input resources. © 2011 Elsevier Ltd. All rights reserved.

  2. SU-E-T-395: Multi-GPU-Based VMAT Treatment Plan Optimization Using a Column-Generation Approach

    International Nuclear Information System (INIS)

    Tian, Z; Shi, F; Jia, X; Jiang, S; Peng, F

    2014-01-01

    Purpose: GPU has been employed to speed up VMAT optimizations from hours to minutes. However, its limited memory capacity makes it difficult to handle cases with a huge dose-deposition-coefficient (DDC) matrix, e.g. those with a large target size, multiple arcs, small beam angle intervals and/or small beamlet size. We propose multi-GPU-based VMAT optimization to solve this memory issue to make GPU-based VMAT more practical for clinical use. Methods: Our column-generation-based method generates apertures sequentially by iteratively searching for an optimal feasible aperture (referred as pricing problem, PP) and optimizing aperture intensities (referred as master problem, MP). The PP requires access to the large DDC matrix, which is implemented on a multi-GPU system. Each GPU stores a DDC sub-matrix corresponding to one fraction of beam angles and is only responsible for calculation related to those angles. Broadcast and parallel reduction schemes are adopted for inter-GPU data transfer. MP is a relatively small-scale problem and is implemented on one GPU. One headand- neck cancer case was used for test. Three different strategies for VMAT optimization on single GPU were also implemented for comparison: (S1) truncating DDC matrix to ignore its small value entries for optimization; (S2) transferring DDC matrix part by part to GPU during optimizations whenever needed; (S3) moving DDC matrix related calculation onto CPU. Results: Our multi-GPU-based implementation reaches a good plan within 1 minute. Although S1 was 10 seconds faster than our method, the obtained plan quality is worse. Both S2 and S3 handle the full DDC matrix and hence yield the same plan as in our method. However, the computation time is longer, namely 4 minutes and 30 minutes, respectively. Conclusion: Our multi-GPU-based VMAT optimization can effectively solve the limited memory issue with good plan quality and high efficiency, making GPUbased ultra-fast VMAT planning practical for real clinical use

  3. SU-E-T-395: Multi-GPU-Based VMAT Treatment Plan Optimization Using a Column-Generation Approach

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Z; Shi, F; Jia, X; Jiang, S [UT Southwestern Medical Ctr at Dallas, Dallas, TX (United States); Peng, F [Carnegie Mellon University, Pittsburgh, PA (United States)

    2014-06-01

    Purpose: GPU has been employed to speed up VMAT optimizations from hours to minutes. However, its limited memory capacity makes it difficult to handle cases with a huge dose-deposition-coefficient (DDC) matrix, e.g. those with a large target size, multiple arcs, small beam angle intervals and/or small beamlet size. We propose multi-GPU-based VMAT optimization to solve this memory issue to make GPU-based VMAT more practical for clinical use. Methods: Our column-generation-based method generates apertures sequentially by iteratively searching for an optimal feasible aperture (referred as pricing problem, PP) and optimizing aperture intensities (referred as master problem, MP). The PP requires access to the large DDC matrix, which is implemented on a multi-GPU system. Each GPU stores a DDC sub-matrix corresponding to one fraction of beam angles and is only responsible for calculation related to those angles. Broadcast and parallel reduction schemes are adopted for inter-GPU data transfer. MP is a relatively small-scale problem and is implemented on one GPU. One headand- neck cancer case was used for test. Three different strategies for VMAT optimization on single GPU were also implemented for comparison: (S1) truncating DDC matrix to ignore its small value entries for optimization; (S2) transferring DDC matrix part by part to GPU during optimizations whenever needed; (S3) moving DDC matrix related calculation onto CPU. Results: Our multi-GPU-based implementation reaches a good plan within 1 minute. Although S1 was 10 seconds faster than our method, the obtained plan quality is worse. Both S2 and S3 handle the full DDC matrix and hence yield the same plan as in our method. However, the computation time is longer, namely 4 minutes and 30 minutes, respectively. Conclusion: Our multi-GPU-based VMAT optimization can effectively solve the limited memory issue with good plan quality and high efficiency, making GPUbased ultra-fast VMAT planning practical for real clinical use.

  4. Electrochemically Smart Bimetallic Materials Featuring Group 11 Metals: In-situ Conductive Network Generation and Its Impact on Cell Capacity

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Esther [Stony Brook Univ., NY (United States)

    2016-11-30

    Our results for this program “Electrochemically smart bimetallic materials featuring Group 11 metals: in-situ conductive matrix generation and its impact on battery capacity, power and reversibility” have been highly successful: 1) we demonstrated material structures which generated in-situ conductive networks through electrochemical activation with increases in conductivity up to 10,000 fold, 2) we pioneered in situ analytical methodology to map the cathodes at several stages of discharge through the use of Energy Dispersive X-ray Diffraction (EDXRD) to elucidate the kinetic dependence of the conductive network formation, and 3) we successfully designed synthetic methodology for direct control of material properties including crystallite size and surface area which showed significant impact on electrochemical behavior.

  5. Roll type conducting polymer legs for rigid-flexible thermoelectric generator

    Directory of Open Access Journals (Sweden)

    Teahoon Park

    2017-07-01

    Full Text Available A roll-type conducting polymer film was explored as a flexible organic p-type thermoelectric leg using poly(3,4-ethylenedioxythiophene (PEDOT doped with tosylate. The PEDOT films were prepared through solution casting polymerization and rolled up for a roll-type leg. Due to the high flexibility, the roll-type PEDOT leg enabled easy contact to both top and bottom electrodes. Simulation on the dynamic heat transfer and convective cooling for a vertically roosted rod- and roll-type PEDOT leg showed that the temperature difference (ΔT between the hot and cold sides of the leg was much higher in the roll than that of the rod. The PEDOT legs were integrated with n-type Bi2Te3 blocks, to give a 36-couple rigid-flexible thermoelectric generator (RF-TEG. The maximum output voltage from the 36-couple RF-TEG under a ΔT of 7.9 K was determined as 36.7 mV along with a high output power of 115 nW. A wearable RF-TEG was prepared upon the combination of the 36-couple RF-TEG with an arm warmer, to afford an output voltage of 10.6 mV, which was generated constantly and steadily from human wrist heat.

  6. Multi-generational responses of a marine polychaete to a rapid change in seawater pCO2.

    Science.gov (United States)

    Rodríguez-Romero, Araceli; Jarrold, Michael D; Massamba-N'Siala, Gloria; Spicer, John I; Calosi, Piero

    2016-10-01

    Little is known of the capacity that marine metazoans have to evolve under rapid p CO 2 changes. Consequently, we reared a marine polychaete, Ophryotrocha labronica , previously cultured for approximately 33 generations under a low/variable pH regime, under elevated and low p CO 2 for six generations. The strain used was found to be tolerant to elevated p CO 2 conditions. In generations F1 and F2 females' fecundity was significantly lower in the low p CO 2 treatment. However, from generation F3 onwards there were no differences between p CO 2 treatments, indicating that trans-generational effects enabled the restoration and maintenance of reproductive output. Whilst the initial fitness recovery was likely driven by trans-generational plasticity (TGP), the results from reciprocal transplant assays, performed using F7 individuals, made it difficult to disentangle between whether TGP had persisted across multiple generations, or if evolutionary adaptation had occurred. Nonetheless, both are important mechanisms for persistence under climate change. Overall, our study highlights the importance of multi-generational experiments in more accurately determining marine metazoans' responses to changes in p CO 2 , and strengthens the case for exploring their use in conservation, by creating specific p CO 2 tolerant strains of keystone ecosystem species.

  7. A Novel Multi-View-Angle Range Images Generation Method for Measurement of Complicated Polyhedron in 3D Space

    Directory of Open Access Journals (Sweden)

    Deming Kong

    2017-01-01

    Full Text Available A new kind of generation method is proposed in this paper to acquire range images for complicated polyhedron in 3D space from a series of view angles. In the proposed generation method, concept of three-view drawing in mechanical cartography is introduced into the range image generation procedure. Negative and positive directions of x-, y-, and z-axes are selected as the view angles to generate the range images for complicated polyhedron in 3D space. Furthermore, a novel iterative operation of mathematical morphology is proposed to ensure that satisfactory range images can be generated for the polyhedron from all the selected view angles. Compared with the existing method based on single view angle and interpolation operation, structure features contained in surface of the complicated polyhedron can be represented more consistently with the reality by using the proposed multi-view-angle range images generation method. The proposed generation method is validated by using an experiment.

  8. Passive dosing of triclosan in multi-generation tests with copepods - Stable exposure concentrations and effects at the low µg l-1 range

    DEFF Research Database (Denmark)

    Ribbenstedt, Anton; Mustajärvi, Lukas; Breitholtz, Magnus

    2017-01-01

    to test the applicability of passive dosing to maintain stable concentrations of the organochlorine bacteriocide triclosan in the water phase during a 6-week multi-generation population development test with the harpacticoid copepod Nitocra spinipes. Triclosan was loaded into silicone (1000 mg), which...... was used as passive dosing phase in the exposure vials. The distribution ratio for triclosan between silicone and water (Dsilicone-water ) was 10466 ± 1927. A population development test was conducted at three concentration levels of triclosan that were measured to be 3-5 µg L(-1) , 7-11 µg L(-1) and 16...... exerted on juvenile development. Progressively lower development index values in the populations exposed to increasing triclosan concentrations suggest developmental retardation. Our results further stress the need for chronic exposure during ecotoxicity testing in chemical risk assessment as even...

  9. Multi-model predictive control method for nuclear steam generator water level

    International Nuclear Information System (INIS)

    Hu Ke; Yuan Jingqi

    2008-01-01

    The dynamics of a nuclear steam generator (SG) is very different according to the power levels and changes as time goes on. Therefore, it is an intractable as well as challenging task to improve the water level control system of the SG. In this paper, a robust model predictive control (RMPC) method is developed for the level control problem. Based on a multi-model framework, a combination of a local nominal model with a polytopic uncertain linear parameter varying (LPV) model is built to approximate the system's non-linear behavior. The optimization problem solved here is based on a receding horizon scheme involving the linear matrix inequality (LMI) technique. Closed loop stability and constraints satisfaction in the entire operating range are guaranteed by the feasibility of the optimization problem. Finally, simulation results show the effectiveness and the good performance of the proposed method

  10. Mainstreaming Multi-Risk Approaches into Policy

    Directory of Open Access Journals (Sweden)

    Anna Scolobig

    2017-12-01

    Full Text Available Multi-risk environments are characterized by domino effects that often amplify the overall risk. Those include chains of hazardous events and increasing vulnerability, among other types of correlations within the risk process. The recently developed methods for multi-hazard and risk assessment integrate interactions between different risks by using harmonized procedures based on common metrics. While the products of these assessments, such as multi-hazard and -risk indexes, maps, cascade scenarios, or warning systems provide innovative and effective information, they also pose specific challenges to policy makers and practitioners due to their novel cross-disciplinary aspects. In this paper we discuss the institutional barriers to the adoption of multi-risk approaches, summarizing the results of the fieldwork conducted in Italy and Guadeloupe and of workshops with disaster risk reduction practitioners from eleven European countries. Results show the need for a clear identification of responsibilities for the implementation of multi-risk approaches, as institutional frameworks for risk reduction remain to this day primarily single-risk centered. Authorities are rarely officially responsible for the management of domino effects between e.g., tsunamis and industrial accidents, earthquake and landslides, floods and electricity network failures. Other barriers for the implementation of multi-risk approaches include the limited measures to reduce exposure at the household level, inadequate financial capacities at the local level and limited public-private partnerships, especially in case of interactions between natural and industrial risks. Adapting the scale of institutions to that of multi-risk environments remains a major challenge to better mainstream multi-risk approaches into policy. To address it, we propose a multi-risk governance framework, which includes the phases of observation, social and institutional context analysis, generation of

  11. Small-Size High-Current Generators for X-Ray Backlighting

    Science.gov (United States)

    Chaikovsky, S. A.; Artyomov, A. P.; Zharova, N. V.; Zhigalin, A. S.; Lavrinovich, I. V.; Oreshkin, V. I.; Ratakhin, N. A.; Rousskikh, A. G.; Fedunin, A. V.; Fedushchak, V. F.; Erfort, A. A.

    2017-12-01

    The paper deals with the soft X-ray backlighting based on the X-pinch as a powerful tool for physical studies of fast processes. Proposed are the unique small-size pulsed power generators operating as a low-inductance capacitor bank. These pulse generators provide the X-pinch-based soft X-ray source (hν = 1-10 keV) of micron size at 2-3 ns pulse duration. The small size and weight of pulse generators allow them to be transported to any laboratory for conducting X-ray backlighting of test objects with micron space resolution and nanosecond exposure time. These generators also allow creating synchronized multi-frame radiographic complexes with frame delay variation in a broad range.

  12. Heat transfer and thermodynamic performance of convective–radiative cooling double layer walls with temperature-dependent thermal conductivity and internal heat generation

    International Nuclear Information System (INIS)

    Torabi, Mohsen; Zhang, Kaili

    2015-01-01

    Highlights: • First and second laws of thermodynamics have been investigated in a composite wall. • Convective–radiative heat transfer is assumed on both surfaces. • Optimum interface location is calculated to minimize the total entropy generation rate. • Thermal conductivities ratio has great effects on the temperature and entropy generation. - Abstract: Composite geometries have numerous applications in industry and scientific researches. This work investigates the temperature distribution, and local and total entropy generation rates within two-layer composite walls using conjugate convection and radiation boundary conditions. Thermal conductivities of the materials of walls are assumed temperature-dependent. Temperature-dependent internal heat generations are also incorporated into the modeling. The differential transformation method (DTM) is used as an analytical technique to tackle the highly nonlinear system of ordinary differential equations. Thereafter, the local and total entropy generation rates are calculated using the DTM formulated temperature distribution. An exact analytical solution, for the temperature-independent model without radiation effect, is also derived. The correctness and accuracy of the DTM solution are checked against the exact solution. After verification, effects of thermophysical parameters such as location of the interface, convection–conduction parameters, radiation–conduction parameters, and internal heat generations, on the temperature distribution, and both local and total entropy generation rates are examined. To deliver the minimum total entropy generation rate, optimum values for some parameters are also found. Since composite walls are widely used in many fields, the abovementioned investigation is a beneficial tool for many engineering industries and scientific fields to minimize the entropy generation, which is the exergy destruction, of the system

  13. Variation of power generation at different buffer types and conductivities in single chamber microbial fuel cells

    KAUST Repository

    Nam, Joo-Youn

    2010-01-15

    Microbial fuel cells (MFCs) are operated with solutions containing various chemical species required for the growth of electrochemically active microorganisms including nutrients and vitamins, substrates, and chemical buffers. Many different buffers are used in laboratory media, but the effects of these buffers and their inherent electrolyte conductivities have not been examined relative to current generation in MFCs. We investigated the effect of several common buffers (phosphate, MES, HEPES, and PIPES) on power production in single chambered MFCs compared to a non-buffered control. At the same concentrations the buffers produced different solution conductivities which resulted in different ohmic resistances and power densities. Increasing the solution conductivities to the same values using NaCl produced comparable power densities for all buffers. Very large increases in conductivity resulted in a rapid voltage drop at high current densities. Our results suggest that solution conductivity at a specific pH for each buffer is more important in MFC studies than the buffer itself given relatively constant pH conditions. Based on our analysis of internal resistance and a set neutral pH, phosphate and PIPES are the most useful buffers of those examined here because pH was maintained close to the pKa of the buffer, maximizing the ability of the buffer to contribute to increase current generation at high power densities. © 2009 Elsevier B.V. All rights reserved.

  14. Variation of power generation at different buffer types and conductivities in single chamber microbial fuel cells.

    Science.gov (United States)

    Nam, Joo-Youn; Kim, Hyun-Woo; Lim, Kyeong-Ho; Shin, Hang-Sik; Logan, Bruce E

    2010-01-15

    Microbial fuel cells (MFCs) are operated with solutions containing various chemical species required for the growth of electrochemically active microorganisms including nutrients and vitamins, substrates, and chemical buffers. Many different buffers are used in laboratory media, but the effects of these buffers and their inherent electrolyte conductivities have not been examined relative to current generation in MFCs. We investigated the effect of several common buffers (phosphate, MES, HEPES, and PIPES) on power production in single chambered MFCs compared to a non-buffered control. At the same concentrations the buffers produced different solution conductivities which resulted in different ohmic resistances and power densities. Increasing the solution conductivities to the same values using NaCl produced comparable power densities for all buffers. Very large increases in conductivity resulted in a rapid voltage drop at high current densities. Our results suggest that solution conductivity at a specific pH for each buffer is more important in MFC studies than the buffer itself given relatively constant pH conditions. Based on our analysis of internal resistance and a set neutral pH, phosphate and PIPES are the most useful buffers of those examined here because pH was maintained close to the pK(a) of the buffer, maximizing the ability of the buffer to contribute to increase current generation at high power densities. Copyright 2009 Elsevier B.V. All rights reserved.

  15. Multi area and multistage expansion-planning of electricity supply with sustainable energy development criteria: a multi objective model

    Energy Technology Data Exchange (ETDEWEB)

    Unsihuay-Vila, Clodomiro; Marangon-Lima, J.W.; Souza, A.C Zambroni de [Universidade Federal de Itajuba (UNIFEI), MG (Brazil)], emails: clodomirounsihuayvila @gmail.com, marangon@unifei.edu.br, zambroni@unifei.edu.br; Perez-Arriaga, I.J. [Universidad Pontificia Comillas, Madrid (Spain)], email: ipa@mit.edu

    2010-07-01

    A novel multi objective, multi area and multistage model to long-term expansion-planning of integrated generation and transmission corridors incorporating sustainable energy developing is presented in this paper. The proposed MESEDES model is a multi-regional multi-objective and 'bottom-up' energy model which considers the electricity generation/transmission value-chain, i.e., power generation alternatives including renewable, nuclear and traditional thermal generation along with transmission corridors. The model decides the optimal location and timing of the electricity generation/transmission abroad the multistage planning horizon. The MESEDES model considers three objectives belonging to sustainable energy development criteria such as: a) the minimization of investments and operation costs of : power generation, transmission corridors, energy efficiency (demand side management (DSM) programs) considering CO2 capture technologies; b) minimization of Life Cycle Greenhouse Gas Emissions (LC GHG); c) maximization of the diversification of electricity generation mix. The proposed model consider aspects of the carbon abatement policy under the CDM - Clean Development Mechanism or European Union Greenhouse Gas Emission Trading Scheme. A case study is used to illustrate the proposed framework. (author)

  16. Improving Multi-Instance Multi-Label Learning by Extreme Learning Machine

    Directory of Open Access Journals (Sweden)

    Ying Yin

    2016-05-01

    Full Text Available Multi-instance multi-label learning is a learning framework, where every object is represented by a bag of instances and associated with multiple labels simultaneously. The existing degeneration strategy-based methods often suffer from some common drawbacks: (1 the user-specific parameter for the number of clusters may incur the effective problem; (2 SVM may bring a high computational cost when utilized as the classifier builder. In this paper, we propose an algorithm, namely multi-instance multi-label (MIML-extreme learning machine (ELM, to address the problems. To our best knowledge, we are the first to utilize ELM in the MIML problem and to conduct the comparison of ELM and SVM on MIML. Extensive experiments have been conducted on real datasets and synthetic datasets. The results show that MIMLELM tends to achieve better generalization performance at a higher learning speed.

  17. O muco traqueobrônquico humano mantido em temperatura ambiente e suas propriedades físico-químicas Physicochemical properties of human tracheobronchial sputum maintained at room temperature

    Directory of Open Access Journals (Sweden)

    Renata Claudia Zanchet

    2007-02-01

    Full Text Available OBJETIVO: Verificar a influência da permanência em temperatura ambiente na análise da transportabilidade por ação ciliar e por tosse e do ângulo de contato do muco traqueobrônquico. MÉTODOS: Foi coletado muco hialino de 30 indivíduos sem doença pulmonar, e purulento de vinte pacientes com bronquiectasia. As amostras foram analisadas logo após a coleta e novamente após 24 h. RESULTADOS: Para o muco purulento, após 24 h em temperatura ambiente, houve aumento no deslocamento por tosse (96 ± 50 vs. 118 ± 61 mm e diminuição do ângulo de contato (32 ± 6 vs. 27 ± 6 graus (p OBJECTIVE: To evaluate the effect that maintaining tracheobronchial sputum at room temperature has on the analysis of ciliary transport and cough, as well as on the contact angle. METHODS: Hyaline sputum was collected from 30 individuals without pulmonary diseases, and purulent sputum was collected from patients with bronchiectasis. The samples were analyzed immediately after collection and again after 24 h. RESULTS: After 24 h at room temperature, the purulent sputum presented an increase in cough-induced dislodgment (96 ± 50 vs. 118 ± 61 mm and a decrease in the contact angle (32 ± 6 vs. 27 ± 6 degrees (p < 0.05. For the hyaline sputum, there were no alterations in the parameters analyzed. CONCLUSION: Hyaline tracheobronchial sputum can be stored in room temperature for 24 h without presenting alterations in ciliary transport or contact angle. However, purulent sputum should not be stored at room temperature for many hours, since ciliary transport and contact angle might be altered as a result.

  18. What is the benefit of driving a hydrological model with data from a multi-site weather generator compared to data from a simple delta change approach?"

    Science.gov (United States)

    Rössler, Ole; Keller, Denise; Fischer, Andreas

    2016-04-01

    . Recently, a multi-site weather generator was developed and tested for downscaling purposes over Switzerland. The weather generator is of type Richardson, that is run with spatially correlated random number streams to ensure spatial consistency. As a downside, multi-site weather generators are much more complex to develop, but they are a very promising alternative downscaling technique. A new multi-site-weather generator was developed for Switzerland in a previous study (Keller et al. 2014). In this study, we tested this new multi-site-weather generator against the "standard" delta change derived data in a hydrological impact assessment study that focused on runoff in the meso-scale catchment of the river Thur catchment. Two hydrological models of different complexity were run with the data sets under present (1980-2009) and under future conditions (2070-2099), assuming the SRES A1B emission2070-2100 scenario conditions. Eight meteorological stations were used to interpolate a meteorological field that served as input to calibrate and validate the two hydrological models against runoff. The downscaling intercomparison was done for We applied 10 GCM-RCM combinations simulations of the ENSEMBLES. In case of the weather generator, that allows for multiple synthetic realizations, we generated for which change factors for each station (delta change approach) were available and generated 25 realizations of multi-site weather. with each climate model projection. Results show that the delta change driven data constitutes only one appropriate representation compared to theof a bandwidth of runoff projections yielded by the multi-site weather generator data. Especially oOn average, differences between both the two approaches are small. Low and high runoff Runoff values to both extremes are however better reproduced with the weather generator driven data set. The stochastic representation of multiday rainfall events are considered as the main reason. Hence, tThere is a clear yet small

  19. Wavelet Based Protection Scheme for Multi Terminal Transmission System with PV and Wind Generation

    Science.gov (United States)

    Manju Sree, Y.; Goli, Ravi kumar; Ramaiah, V.

    2017-08-01

    A hybrid generation is a part of large power system in which number of sources usually attached to a power electronic converter and loads are clustered can operate independent of the main power system. The protection scheme is crucial against faults based on traditional over current protection since there are adequate problems due to fault currents in the mode of operation. This paper adopts a new approach for detection, discrimination of the faults for multi terminal transmission line protection in presence of hybrid generation. Transient current based protection scheme is developed with discrete wavelet transform. Fault indices of all phase currents at all terminals are obtained by analyzing the detail coefficients of current signals using bior 1.5 mother wavelet. This scheme is tested for different types of faults and is found effective for detection and discrimination of fault with various fault inception angle and fault impedance.

  20. An Approach for Patient-Specific Multi-domain Vascular Mesh Generation Featuring Spatially Varying Wall Thickness Modeling

    OpenAIRE

    Raut, Samarth S.; Liu, Peng; Finol, Ender A.

    2015-01-01

    In this work, we present a computationally efficient image-derived volume mesh generation approach for vasculatures that implements spatially varying patient-specific wall thickness with a novel inward extrusion of the wall surface mesh. Multi-domain vascular meshes with arbitrary numbers, locations, and patterns of both iliac bifurcations and thrombi can be obtained without the need to specify features or landmark points as input. In addition, the mesh output is coordinate-frame independent ...

  1. Topological responses from chiral anomaly in multi-Weyl semimetals

    Science.gov (United States)

    Huang, Ze-Min; Zhou, Jianhui; Shen, Shun-Qing

    2017-08-01

    Multi-Weyl semimetals are a kind of topological phase of matter with discrete Weyl nodes characterized by multiple monopole charges, in which the chiral anomaly, the anomalous nonconservation of an axial current, occurs in the presence of electric and magnetic fields. Electronic transport properties related to the chiral anomaly in the presence of both electromagnetic fields and axial electromagnetic fields in multi-Weyl semimetals are systematically studied. It has been found that the anomalous Hall conductivity has a modification linear in the axial vector potential from inhomogeneous strains. The axial electric field leads to an axial Hall current that is proportional to the distance of Weyl nodes in momentum space. This axial current may generate chirality accumulation of Weyl fermions through delicately engineering the axial electromagnetic fields even in the absence of external electromagnetic fields. Therefore this work provides a nonmagnetic mechanism of generation of chirality accumulation in Weyl semimetals and might shed new light on the application of Weyl semimetals in the emerging field of valleytronics.

  2. Unsteady Flow of Reactive Viscous, Heat Generating/Absorbing Fluid with Soret and Variable Thermal Conductivity

    Directory of Open Access Journals (Sweden)

    I. J. Uwanta

    2014-01-01

    Full Text Available This study investigates the unsteady natural convection and mass transfer flow of viscous reactive, heat generating/absorbing fluid in a vertical channel formed by two infinite parallel porous plates having temperature dependent thermal conductivity. The motion of the fluid is induced due to natural convection caused by the reactive property as well as the heat generating/absorbing nature of the fluid. The solutions for unsteady state temperature, concentration, and velocity fields are obtained using semi-implicit finite difference schemes. Perturbation techniques are used to get steady state expressions of velocity, concentration, temperature, skin friction, Nusselt number, and Sherwood number. The effects of various flow parameters such as suction/injection (γ, heat source/sinks (S, Soret number (Sr, variable thermal conductivity δ, Frank-Kamenetskii parameter λ, Prandtl number (Pr, and nondimensional time t on the dynamics are analyzed. The skin friction, heat transfer coefficients, and Sherwood number are graphically presented for a range of values of the said parameters.

  3. Thermal conductivity of U–Mo/Al dispersion fuel. Effects of particle shape and size, stereography, and heat generation

    International Nuclear Information System (INIS)

    Cho, Tae Won; Sohn, Dong-Seong; Kim, Yeon Soo

    2015-01-01

    This paper describes the effects of particle sphericity, interfacial thermal resistance, stereography, and heat generation on the thermal conductivity of U–Mo/Al dispersion fuel. The ABAQUS finite element method (FEM) tool was used to calculate the effective thermal conductivity of U–Mo/Al dispersion fuel by implementing fuel particles. For U–Mo/Al, the particle sphericity effect was insignificant. However, if the effect of the interfacial thermal resistance between the fuel particles and Al matrix was considered, the thermal conductivity of U–Mo/Al was increased as the particle size increases. To examine the effect of stereography, we compared the two-dimensional modeling and three-dimensional modeling. The results showed that the two-dimensional modeling predicted lower than the three-dimensional modeling. We also examined the effect of the presence of heat sources in the fuel particles and found a decrease in thermal conductivity of U–Mo/Al from that of the typical homogeneous heat generation modeling. (author)

  4. A Model for Generating Multi-hazard Scenarios

    Science.gov (United States)

    Lo Jacomo, A.; Han, D.; Champneys, A.

    2017-12-01

    Communities in mountain areas are often subject to risk from multiple hazards, such as earthquakes, landslides, and floods. Each hazard has its own different rate of onset, duration, and return period. Multiple hazards tend to complicate the combined risk due to their interactions. Prioritising interventions for minimising risk in this context is challenging. We developed a probabilistic multi-hazard model to help inform decision making in multi-hazard areas. The model is applied to a case study region in the Sichuan province in China, using information from satellite imagery and in-situ data. The model is not intended as a predictive model, but rather as a tool which takes stakeholder input and can be used to explore plausible hazard scenarios over time. By using a Monte Carlo framework and varrying uncertain parameters for each of the hazards, the model can be used to explore the effect of different mitigation interventions aimed at reducing the disaster risk within an uncertain hazard context.

  5. Generating a high brightness multi-kilowatt laser by dense spectral combination of VBG stabilized single emitter laser diodes

    Science.gov (United States)

    Fritsche, H.; Koch, Ralf; Krusche, B.; Ferrario, F.; Grohe, Andreas; Pflueger, S.; Gries, W.

    2014-05-01

    Generating high power laser radiation with diode lasers is commonly realized by geometrical stacking of diode bars, which results in high output power but poor beam parameter product (BPP). The accessible brightness in this approach is limited by the fill factor, both in slow and fast axis. By using a geometry that accesses the BPP of the individual diodes, generating a multi kilowatt diode laser with a BPP comparable to fiber lasers is possible. We will demonstrate such a modular approach for generating multi kilowatt lasers by combining single emitter diode lasers. Single emitter diodes have advantages over bars, mainly a simplified cooling, better reliability and a higher brightness per emitter. Additionally, because single emitters can be arranged in many different geometries, they allow building laser modules where the brightness of the single emitters is preserved. In order to maintain the high brightness of the single emitter we developed a modular laser design which uses single emitters in a staircase arrangement, then coupling two of those bases with polarization combination which is our basic module. Those modules generate up to 160 W with a BPP better than 7.5 mm*mrad. For further power scaling wavelength stabilization is crucial. The wavelength is stabilized with only one Volume Bragg Grating (VBG) in front of a base providing the very same feedback to all of the laser diodes. This results in a bandwidth of BPP better than 7.5 mm*mrad, which can easily coupled into a 100 μm fiber and 0.15 NA.

  6. GENERATION OF MULTI-LOD 3D CITY MODELS IN CITYGML WITH THE PROCEDURAL MODELLING ENGINE RANDOM3DCITY

    Directory of Open Access Journals (Sweden)

    F. Biljecki

    2016-09-01

    Full Text Available The production and dissemination of semantic 3D city models is rapidly increasing benefiting a growing number of use cases. However, their availability in multiple LODs and in the CityGML format is still problematic in practice. This hinders applications and experiments where multi-LOD datasets are required as input, for instance, to determine the performance of different LODs in a spatial analysis. An alternative approach to obtain 3D city models is to generate them with procedural modelling, which is – as we discuss in this paper – well suited as a method to source multi-LOD datasets useful for a number of applications. However, procedural modelling has not yet been employed for this purpose. Therefore, we have developed RANDOM3DCITY, an experimental procedural modelling engine for generating synthetic datasets of buildings and other urban features. The engine is designed to produce models in CityGML and does so in multiple LODs. Besides the generation of multiple geometric LODs, we implement the realisation of multiple levels of spatiosemantic coherence, geometric reference variants, and indoor representations. As a result of their permutations, each building can be generated in 392 different CityGML representations, an unprecedented number of modelling variants of the same feature. The datasets produced by RANDOM3DCITY are suited for several applications, as we show in this paper with documented uses. The developed engine is available under an open-source licence at Github at http://github.com/tudelft3d/Random3Dcity.

  7. Skill, Judgement and Conduct for the First Generation of Neurosurgeons, 1900-1930.

    Science.gov (United States)

    Gavrus, Delia

    2015-07-01

    Historical contingency complicates a reading of skill as a self-explanatory and always positive attribute. By focusing on the attempts of the first generation of neurosurgeons to build a community and fashion a collective neurosurgical self, this article highlights the extent to which the relationship between surgical skill and professional judgement is reflected in broader concerns that shape the landscape of medicine at a given time. Some early twentieth-century surgeons expressed concern about the spectacularisation of surgery and the skilful but problematic work of 'brilliant operators'. The neurosurgeons' policies of inclusion and exclusion show that in the process of fashioning a neurosurgical persona, this first generation sanctioned specific norms of conduct underwritten by similar moral imperatives, such as self-control. These norms governed the doctors' work both in the operating room and on the public stage (in their engagement with the press). The meetings of the first neurosurgical society staged a critical encounter between the host neurosurgeon and the members who watched him perform surgery. These technical performances in the operating theatre, followed by discussions, were designed to encourage particular norms, to negotiate surgical knowledge, and to demonstrate the skills and character of the neurosurgeon. The performances acted as a technology of the self that aligned the operator to a community and helped that community refine its norms of surgical conduct. The awkward surgeon with inferior technical ability was preferable to the brilliant but vain operator who lacked the capacity to judge when he should not deploy his spectacular skills.

  8. Development of a Vibration-Based Electromagnetic Energy Harvester by a Conductive Direct-Write Process

    Directory of Open Access Journals (Sweden)

    Yao-Yun Feng

    2017-03-01

    Full Text Available A conductive direct-write process of multilayered coils for micro electromagnetic generators is proposed. This novel approach of using silver ink to form the conductive structures largely reduces the fabrication complexity, and it provides a faster alternative to the conventional semiconductor methods. Multi-layered coils with insulation were accurately layered on a micromachined cantilevered diaphragm by a dispenser. Coils several layers thick could be used to increase the power output and double coils were separated by a layer of insulation. Six prototypes, all capable of efficient conversion of vibrational energy into electrical energy, were fabricated. The experimental results, which include measurements of the electromotive force and power output, are presented. Prototypes with two coils and thicker conducting layers had less resistance and the power output was much more than that of a single-coil unit. This generator can produce 82 nW of power at a resonance frequency of 275 Hz under 5 g excitation.

  9. Nonlinear decentralized robust governor control for hydroturbine-generator sets in multi-machine power systems

    Energy Technology Data Exchange (ETDEWEB)

    Qiang Lu; Yusong Sun; Yuanzhang Sun [Tsinghua University, Beijing (China). Dept. of Electrical Engineering; Felix F Wu; Yixin Ni [University of Hong Kong (China). Dept. of Electrical and Electronic Engineering; Yokoyama, Akihiko [University of Tokyo (Japan). Dept. of Electrical Engineering; Goto, Masuo; Konishi, Hiroo [Hitachi Ltd., Tokyo (Japan). Power System Div.

    2004-06-01

    A novel nonlinear decentralized robust governor control for hydroturbine-generator sets in multi-machine power systems is suggested in this paper. The nonelastic water hammer effect and disturbances are considered in the modeling. The advanced differential geometry theory, nonlinear robust control theory and the dynamic feedback method are combined to solve the problem. The nonlinear decentralized robust control law for the speed governor of hydroturbine-generators has been derived. The input signals to the proposed controller are all local measurements and independent to the system parameters. The derived control law guarantees the integrated system stability with disturbance attenuation, which is significant to the real power system application. Computer tests on an 8-machine, 36-bus power system show clearly the effectiveness of the new control strategy in transient stability enhancement and disturbance attenuation. The computer test results based on the suggested controller are compared favorably with those based on the conventional linear governor control. (author)

  10. Multi-Agent System based Event-Triggered Hybrid Controls for High-Security Hybrid Energy Generation Systems

    DEFF Research Database (Denmark)

    Dou, Chun-Xia; Yue, Dong; Guerrero, Josep M.

    2017-01-01

    This paper proposes multi-agent system based event- triggered hybrid controls for guaranteeing energy supply of a hybrid energy generation system with high security. First, a mul-ti-agent system is constituted by an upper-level central coordi-nated control agent combined with several lower......-level unit agents. Each lower-level unit agent is responsible for dealing with internal switching control and distributed dynamic regula-tion for its unit system. The upper-level agent implements coor-dinated switching control to guarantee the power supply of over-all system with high security. The internal...

  11. The molecular mechanism of multi-ion conduction in K{sup +} channels

    Energy Technology Data Exchange (ETDEWEB)

    Gwan, J.F.

    2007-01-19

    Steered molecular dynamics (SMD) simulation method is applied to a fully solvated membrane-channel model for studying the ion permeation process in potassium channels. The channel model is based on the crystallographic structure of a prokaryotic K{sup +} channel- the KcsA channel, which is a representative of most known eukaryotic K{sup +} channels. It has long been proposed that the ion transportation in a conventional K{sup +}-channel follows a multi-ion fashion: permeating ions line in a queue in the channel pore and move in a single file through the channel. The conventional view of multi-ion transportation is that the electrostatic repulsion between ions helps to overcome the attraction between ions and the channel pore. In this study, we proposed two SMD simulation schemes, referred to 'the single-ion SMD' simulations and 'the multi-ion SMD' simulations. Concerted movements of a K-W-K sequence in the selectivity filter were observed in the single-ion SMD simulations. The analysis of the concerted movement reveals the molecular mechanism of the multi-ion transportation. It shows that, rather than the long range electrostatic interaction, the short range polar interaction is a more dominant factor in the multi-ion transportation. The polar groups which play a role in the concerted transportation are the water molecules and the backbone carbonyl groups of the selectivity filter. The polar interaction is sensitive to the relative orientation of the polar groups. By changing the orientation of a polar group, the interaction may switch from attractive to repulsive or vice versa. By this means, the energy barrier between binding sites in the selectivity filter can be switched on and off, and therefore the K{sup +} may be able to move to the neighboring binding site without an external driving force. The concerted transportation in the selectivity filter requires a delicate cooperation between K{sup +}, waters, and the backbone carbonyl groups. To

  12. Generation und Familie – über die Ambivalenz eines multistrukturellen Verhältnisses Generation and Family—On the Ambivalence of Multi-Structural Relationships

    Directory of Open Access Journals (Sweden)

    Vera Bollmann

    2008-07-01

    Full Text Available Der Sammelband Generationen und Familien, welcher dem Soziologen Kurt Lüscher zum 70. Geburtstag gewidmet ist, stellt eine kritische Gegenwartsdiagnose des aktuellen Theorie- und Forschungsstandes zu diesem Thema dar. Schon in ihrem Vorwort machen die beiden Herausgeber auf die Diversität und den Facettenreichtum des Familien- und Generationenkonzeptes in modernen Gesellschaften aufmerksam: familiale Generationenbeziehungen werden in ganz unterschiedlicher Weise gelebt, und je nach theoretischer Lesart ergeben sich vielfältige Deutungsmuster. Die Beiträge nähern sich der Verflechtung von Familie, Generation und Gesellschaft sowohl in theoretischer als auch in empirischer Hinsicht. Inhaltlich reihen sie sich in drei übergeordnete Themenblöcke ein: „Generationen, Generationenverhältnisse und Generationenbeziehungen“, „Familie, Alltag und Identität“ und „Soziologie, Recht und Politik”.The collected volume Generationen und Familien, which is dedicated to the sociologist Kurt Lüscher on his 70th birthday, presents a critical diagnosis of the current state of theory and research on this theme. The editors point to the diversity and multi-structural nature of the concept of family and generation in their forward to the volume: Familial relations between generations are experienced in very different ways and, depending upon the theoretical reading, they provide multiple patterns for interpretation. The contributions approach the linkage between family, generation, and society in a theoretical and an empirical manner. The contents can be divided into three general thematic blocks: “Generation, generational relations, and generational relationships,” “family, daily life, and identity,” and “sociology, law, and politics.”

  13. Tracking multi-generational colonization of the breeding grounds by monarch butterflies in eastern North America

    Science.gov (United States)

    Flockhart, D. T. Tyler; Wassenaar, Leonard I.; Martin, Tara G.; Hobson, Keith A.; Wunder, Michael B.; Norris, D. Ryan

    2013-01-01

    Insect migration may involve movements over multiple breeding generations at continental scales, resulting in formidable challenges to their conservation and management. Using distribution models generated from citizen scientist occurrence data and stable-carbon and -hydrogen isotope measurements, we tracked multi-generational colonization of the breeding grounds of monarch butterflies (Danaus plexippus) in eastern North America. We found that monarch breeding occurrence was best modelled with geographical and climatic variables resulting in an annual breeding distribution of greater than 12 million km2 that encompassed 99% occurrence probability. Combining occurrence models with stable isotope measurements to estimate natal origin, we show that butterflies which overwintered in Mexico came from a wide breeding distribution, including southern portions of the range. There was a clear northward progression of monarchs over successive generations from May until August when reproductive butterflies began to change direction and moved south. Fifth-generation individuals breeding in Texas in the late summer/autumn tended to originate from northern breeding areas rather than regions further south. Although the Midwest was the most productive area during the breeding season, monarchs that re-colonized the Midwest were produced largely in Texas, suggesting that conserving breeding habitat in the Midwest alone is insufficient to ensure long-term persistence of the monarch butterfly population in eastern North America. PMID:23926146

  14. A multi-component matrix loop algebra and a unified expression of the multi-component AKNS hierarchy and the multi-component BPT hierarchy

    International Nuclear Information System (INIS)

    Zhang Yufeng

    2005-01-01

    A set of multi-component matrix Lie algebra is constructed, which is devote to obtaining a new loop algebra A-bar M-1 . It follows that an isospectral problem is established. By making use of Tu scheme, a Liouville integrable multi-component hierarchy of soliton equations is generated, which possesses the bi-Hamiltonian structures. As its reduction cases, the multi-component AKNS hierarchy and the formalism of the multi-component BPT hierarchy are given, respectively

  15. Prescriptive Methodology as a Generative Tool: A Case Study Conducted at Introductory Interior Design Studio Level in the United Arab Emirates

    Directory of Open Access Journals (Sweden)

    Lina Ahmad

    2017-09-01

    Full Text Available In the U.A.E. (United Arab Emirates, interior design education is often misunderstood as interior decoration, wherein the former is a more comprehensive design approach to spaces formed by structural boundaries and curation of human interaction. The conducted case study addressed a small number of students enrolled in Interior Design Studio I at Zayed University, Abu Dhabi campus. In addition to traditional teaching methods compromised of individual desk critique sessions, group pin-ups and presentations, three innovative methods were implemented as a means of guiding students through the process: direct sequential instruction executed within an assigned time frame, reflection on the surfaced result and use of flat photography or panoramas as means of space communication. Throughout the three implemented stages of the project, and through utilizing the above-described generative methodology, students achieved complex representation and revealed higher spatial order related to human occupation and space inhabitation. This methodology allowed students to channel their work through complex sets of interconnected information and derived an outcome from an accumulative multi-layered resolution. The article presents the process and analyses the achieved outcomes.

  16. Heterogeneous flow in multi-layer joint networks and its influence on incipient karst generation

    Science.gov (United States)

    Wang, X.; Jourde, H.

    2017-12-01

    Various dissolution types (e.g. pipe, stripe and sheet karstic features) have been observed in fractured layered limestones. Yet, due to a large range of structural and hydraulic parameters play a role in the karstification process, the dissolution mechanism, occurring either along fractures or bedding planes, is difficult to quantify. In this study, we use numerical models to investigate the influence of these parameters on the generation of different types of incipient karst. Specifically, we focus on two parameters: the fracture intensity contrast between adjacent layers and the aperture ratio between bedding planes and joints (abed/ajoint). The DFN models were generated using a pseudo-genetic code that considers the stress shadow zone. Flow simulations were performed using a combined finite-volume finite-element simulator under practical boundary conditions. The flow channeling within the fracture networks was characterized by applying a multi-fractal technique. The rock block equivalent permeability (keff) was also calculated to quantify the change in bulk hydraulic properties when changing the selected structural and hydraulic parameters. The flow simulation results show that the abed/ajoint ratio has a first-order control on the heterogeneous distribution of flow in the multi-layer system and on the magnitude of equivalent permeability. When abed/ajoint 0.1, the bedding plane has more control and flow becomes more pervasive and uniform, and the keff is accordingly high. A simple model, accounting for the calculation of the heterogeneous distributions of Damköhler number associated with different aperture ratios, is proposed to predict what type of incipient karst tends to develop under the studied flow conditions.

  17. TRUMP3-JR: a finite difference computer program for nonlinear heat conduction problems

    International Nuclear Information System (INIS)

    Ikushima, Takeshi

    1984-02-01

    Computer program TRUMP3-JR is a revised version of TRUMP3 which is a finite difference computer program used for the solution of multi-dimensional nonlinear heat conduction problems. Pre- and post-processings for input data generation and graphical representations of calculation results of TRUMP3 are avaiable in TRUMP3-JR. The calculation equations, program descriptions and user's instruction are presented. A sample problem is described to demonstrate the use of the program. (author)

  18. Multi-factor authentication

    Science.gov (United States)

    Hamlet, Jason R; Pierson, Lyndon G

    2014-10-21

    Detection and deterrence of spoofing of user authentication may be achieved by including a cryptographic fingerprint unit within a hardware device for authenticating a user of the hardware device. The cryptographic fingerprint unit includes an internal physically unclonable function ("PUF") circuit disposed in or on the hardware device, which generates a PUF value. Combining logic is coupled to receive the PUF value, combines the PUF value with one or more other authentication factors to generate a multi-factor authentication value. A key generator is coupled to generate a private key and a public key based on the multi-factor authentication value while a decryptor is coupled to receive an authentication challenge posed to the hardware device and encrypted with the public key and coupled to output a response to the authentication challenge decrypted with the private key.

  19. Broadband multi-wavelength Brillouin lasers with an operating wavelength range of 1500–1600 nm generated by four-wave mixing in a dual wavelength Brillouin fiber laser cavity

    Science.gov (United States)

    Li, Q.; Jia, Z. X.; Weng, H. Z.; Li, Z. R.; Yang, Y. D.; Xiao, J. L.; Chen, S. W.; Huang, Y. Z.; Qin, W. P.; Qin, G. S.

    2018-05-01

    We demonstrate broadband multi-wavelength Brillouin lasers with an operating wavelength range of 1500–1600 nm and a frequency separation of ~9.28 GHz generated by four-wave mixing in a dual wavelength Brillouin fiber laser cavity. By using one continuous-wave laser as the pump source, multi-wavelength Brillouin lasers with an operating wavelength range of 1554–1574 nm were generated via cascaded Brillouin scattering and four-wave mixing. Interestingly, when pumped by two continuous-wave lasers with an appropriate frequency separation, the operating wavelength range of the multi-wavelength Brillouin lasers was increased to 1500–1600 nm due to cavity-enhanced cascaded four-wave mixing among the frequency components generated by two pump lasers in the dual wavelength Brillouin laser cavity.

  20. Multi-View Multi-Instance Learning Based on Joint Sparse Representation and Multi-View Dictionary Learning.

    Science.gov (United States)

    Li, Bing; Yuan, Chunfeng; Xiong, Weihua; Hu, Weiming; Peng, Houwen; Ding, Xinmiao; Maybank, Steve

    2017-12-01

    In multi-instance learning (MIL), the relations among instances in a bag convey important contextual information in many applications. Previous studies on MIL either ignore such relations or simply model them with a fixed graph structure so that the overall performance inevitably degrades in complex environments. To address this problem, this paper proposes a novel multi-view multi-instance learning algorithm (MIL) that combines multiple context structures in a bag into a unified framework. The novel aspects are: (i) we propose a sparse -graph model that can generate different graphs with different parameters to represent various context relations in a bag, (ii) we propose a multi-view joint sparse representation that integrates these graphs into a unified framework for bag classification, and (iii) we propose a multi-view dictionary learning algorithm to obtain a multi-view graph dictionary that considers cues from all views simultaneously to improve the discrimination of the MIL. Experiments and analyses in many practical applications prove the effectiveness of the M IL.

  1. Demonstration of multi-generational growth of tungsten nanoparticles in hydrogen plasma using in situ laser extinction method

    Science.gov (United States)

    Ouaras, K.; Lombardi, G.; Hassouni, K.

    2018-03-01

    For the first time, we demonstrate that tungsten (W) nanoparticles (NPs) are created when a tungsten target is exposed to low-pressure, high density hydrogen plasma. The plasma was generated using a novel dual plasma system combining a microwave discharge and a pulsed direct-current (DC) discharge. The tungsten surface originates in the multi-generational formation of a significant population of 30-70 nm diameter particles when the W cathode is biased at ~  -1 kV and submitted to ~1020 m2 s-1 H+/H2+ /H3+ ions flux. The evidenced NPs formation should be taking into account as one of the consequence of the plasma surface interaction outcomes, especially for fusion applications.

  2. Patterning conductive PDMS nanocomposite in an elastomer using microcontact printing

    International Nuclear Information System (INIS)

    Liu, Chao-Xuan; Choi, Jin-Woo

    2009-01-01

    This paper introduces a simple method of embedding conductive and flexible elastomer micropatterns into a bulk elastomer. Employing microcontact printing and cast molding techniques, patterns consisting of conductive poly(dimethylsiloxane) (PDMS) composites mixed with multi-walled carbon nanotubes (MWCNTs) are embedded into bulk PDMS to form all-elastomer devices. To pattern conductive composites, a micromachined printing mold is utilized to transfer composite ink from a spin-coated thin layer to another substrate. Distinct from previously reported approaches, the printing mold in this technique, once fabricated, can be repeatedly used to generate new patterns and therefore greatly simplifies the device fabrication process and improves its efficiency. Manufactured devices with embedded conductive patterns exhibit excellent mechanical flexibility. With characterization of printing reliability, electrical conductivity of the composites is also shown with different loading percentages of MWCNTs. Furthermore, a simple strain gauge was fabricated and tested to demonstrate the potential applications of embedded conductive patterns. Overall, this approach demonstrates feasibility to be a simple method to pattern conductive elastomers that work as electrodes or sensing probes in PDMS-based devices. With further development, this technology yields many potential applications in lab-on-a-chip systems

  3. Operating experiences with 1 MW steam generator

    Energy Technology Data Exchange (ETDEWEB)

    Sano, A; Kanamori, A; Tsuchiya, T

    1975-07-01

    1 MW steam generator, which was planned as the first stage of steam generator development in Power Reactor and Nuclear Fuel Corp. (PNC) in Japan, is a single-unit, once-through, integrated shell and tube type with multi-helical coil tubes. It was completed in Oarai Engineering Center of PNC in March of 1971, and the various performance tests were carried out up to April, 1972. After the dismantle of the steam generator for structural inspection and material test, it was restored with some improvements. In this second 1 MW steam generator, small leak occurred twice during normal operation. After repairing the failure, the same kind of performance tests as the first steam generator were conducted in order to verify the thermal insulation effect of argon gas in downcomer zone from March to June, 1974. In this paper the above operating experiences were presented including the outline of some performance test results. (author)

  4. Sensitivity Analysis and Stray Capacitance of Helical Flux Compression Generator with Multi Layer Filamentary Conductor in Rectangular Cross-Section

    Directory of Open Access Journals (Sweden)

    M. E. Mosleh

    2012-03-01

    Full Text Available This paper presents an approach to calculate the equivalent stray capacitance (SC of n-turn of the helical flux compression generator (HFCG coil with multi layer conductor wire filaments (MLCWF in the form of rectangular cross-section. This approach is based on vespiary regular hexagonal (VRH model. In this method, wire filaments of the generator coil are separated into many very small similar elementary cells. By the expanded explosion in the liner and move explosion to the end of the liner, the coil turns number will be reduced. So, the equivalent SC of the HFCG will increase. The results show that by progress of explosion and decrease of the turns’ number in the generator coil total capacitance of the generator increases until the explosion reaches to the second turn. When only one turn remains in the circuit, a decrease occurs in the total capacitance of the generator.

  5. Automatic Generation of Agents using Reusable Soft Computing Code Libraries to develop Multi Agent System for Healthcare

    OpenAIRE

    Priti Srinivas Sajja

    2015-01-01

    This paper illustrates architecture for a multi agent system in healthcare domain. The architecture is generic and designed in form of multiple layers. One of the layers of the architecture contains many proactive, co-operative and intelligent agents such as resource management agent, query agent, pattern detection agent and patient management agent. Another layer of the architecture is a collection of libraries to auto-generate code for agents using soft computing techni...

  6. Influence of climate change on the multi-generation toxicity to Enchytraeus crypticus of soils polluted by metal/metalloid mining wastes

    NARCIS (Netherlands)

    Barmentlo, S.H.; van Gestel, C.A.M.; Alvarez-Rogel, J.; Gonzalez Alcaraz, M.N.

    2017-01-01

    This study aimed at assessing the effects of increased air temperature and reduced soil moisture content on the multi-generation toxicity of a soil polluted by metal/metalloid mining wastes. Enchytraeus crypticus was exposed to dilution series of the polluted soil in Lufa 2.2 soil under different

  7. Simulation of multi-photon emission isotopes using time-resolved SimSET multiple photon history generator

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Chih-Chieh; Lin, Hsin-Hon; Lin, Chang-Shiun; Chuang, Keh-Shih [Department of Biomedical Engineering and Environmental Sciences, National Tsing-HuaUniversity, Hsinchu, Taiwan (China); Jan, Meei-Ling [Health Physics Division, Institute of Nuclear Energy Research, Atomic Energy Council, Taoyuan, Taiwan (China)

    2015-07-01

    Abstract-Multiple-photon emitters, such as In-111 or Se-75, have enormous potential in the field of nuclear medicine imaging. For example, Se-75 can be used to investigate the bile acid malabsorption and measure the bile acid pool loss. The simulation system for emission tomography (SimSET) is a well-known Monte Carlo simulation (MCS) code in nuclear medicine for its high computational efficiency. However, current SimSET cannot simulate these isotopes due to the lack of modeling of complex decay scheme and the time-dependent decay process. To extend the versatility of SimSET for simulation of those multi-photon emission isotopes, a time-resolved multiple photon history generator based on SimSET codes is developed in present study. For developing the time-resolved SimSET (trSimSET) with radionuclide decay process, the new MCS model introduce new features, including decay time information and photon time-of-flight information, into this new code. The half-life of energy states were tabulated from the Evaluated Nuclear Structure Data File (ENSDF) database. The MCS results indicate that the overall percent difference is less than 8.5% for all simulation trials as compared to GATE. To sum up, we demonstrated that time-resolved SimSET multiple photon history generator can have comparable accuracy with GATE and keeping better computational efficiency. The new MCS code is very useful to study the multi-photon imaging of novel isotopes that needs the simulation of lifetime and the time-of-fight measurements. (authors)

  8. Cyndi: a multi-objective evolution algorithm based method for bioactive molecular conformational generation.

    Science.gov (United States)

    Liu, Xiaofeng; Bai, Fang; Ouyang, Sisheng; Wang, Xicheng; Li, Honglin; Jiang, Hualiang

    2009-03-31

    Conformation generation is a ubiquitous problem in molecule modelling. Many applications require sampling the broad molecular conformational space or perceiving the bioactive conformers to ensure success. Numerous in silico methods have been proposed in an attempt to resolve the problem, ranging from deterministic to non-deterministic and systemic to stochastic ones. In this work, we described an efficient conformation sampling method named Cyndi, which is based on multi-objective evolution algorithm. The conformational perturbation is subjected to evolutionary operation on the genome encoded with dihedral torsions. Various objectives are designated to render the generated Pareto optimal conformers to be energy-favoured as well as evenly scattered across the conformational space. An optional objective concerning the degree of molecular extension is added to achieve geometrically extended or compact conformations which have been observed to impact the molecular bioactivity (J Comput -Aided Mol Des 2002, 16: 105-112). Testing the performance of Cyndi against a test set consisting of 329 small molecules reveals an average minimum RMSD of 0.864 A to corresponding bioactive conformations, indicating Cyndi is highly competitive against other conformation generation methods. Meanwhile, the high-speed performance (0.49 +/- 0.18 seconds per molecule) renders Cyndi to be a practical toolkit for conformational database preparation and facilitates subsequent pharmacophore mapping or rigid docking. The copy of precompiled executable of Cyndi and the test set molecules in mol2 format are accessible in Additional file 1. On the basis of MOEA algorithm, we present a new, highly efficient conformation generation method, Cyndi, and report the results of validation and performance studies comparing with other four methods. The results reveal that Cyndi is capable of generating geometrically diverse conformers and outperforms other four multiple conformer generators in the case of

  9. Cyndi: a multi-objective evolution algorithm based method for bioactive molecular conformational generation

    Directory of Open Access Journals (Sweden)

    Li Honglin

    2009-03-01

    Full Text Available Abstract Background Conformation generation is a ubiquitous problem in molecule modelling. Many applications require sampling the broad molecular conformational space or perceiving the bioactive conformers to ensure success. Numerous in silico methods have been proposed in an attempt to resolve the problem, ranging from deterministic to non-deterministic and systemic to stochastic ones. In this work, we described an efficient conformation sampling method named Cyndi, which is based on multi-objective evolution algorithm. Results The conformational perturbation is subjected to evolutionary operation on the genome encoded with dihedral torsions. Various objectives are designated to render the generated Pareto optimal conformers to be energy-favoured as well as evenly scattered across the conformational space. An optional objective concerning the degree of molecular extension is added to achieve geometrically extended or compact conformations which have been observed to impact the molecular bioactivity (J Comput -Aided Mol Des 2002, 16: 105–112. Testing the performance of Cyndi against a test set consisting of 329 small molecules reveals an average minimum RMSD of 0.864 Å to corresponding bioactive conformations, indicating Cyndi is highly competitive against other conformation generation methods. Meanwhile, the high-speed performance (0.49 ± 0.18 seconds per molecule renders Cyndi to be a practical toolkit for conformational database preparation and facilitates subsequent pharmacophore mapping or rigid docking. The copy of precompiled executable of Cyndi and the test set molecules in mol2 format are accessible in Additional file 1. Conclusion On the basis of MOEA algorithm, we present a new, highly efficient conformation generation method, Cyndi, and report the results of validation and performance studies comparing with other four methods. The results reveal that Cyndi is capable of generating geometrically diverse conformers and outperforms

  10. Flexible endoscopy for pediatric tracheobronchial metallic stent placement, maintenance and long-term outcomes

    Science.gov (United States)

    2018-01-01

    Objectives To assess the placement, surveillance management and long-term outcomes of the tracheobronchial (TB) balloon expandable metallic stent (BEMS) managed by therapeutic flexible endoscopy (TFE). Methods This is a retrospective review and analysis of all computerized medical records and related flexible endoscopy videos of pediatric patients who received TB BEMS during 20 years period, from January 1997 to December 2016. TFE techniques with forceps debridement, balloon dilatation and laser ablation were used to implant stents, perform regular surveillance, maintain their functions, and expand the diameters of BEMS. Short-length (30cm-36cm) endoscopes of OD 3.2mm to 5.0mm coupled with the noninvasive ventilation, without ventilation bag, mask or airway tube, supported the whole procedures. Results 146 BEMS were implanted in 87 consecutive children, including 84 tracheal, 15 carinal and 47 bronchial stents. At the time of placement, the mean age was 35.6 ± 54.6 month-old (range 0.3–228) and the mean body weight was 13.9 ± 10.6 kg (range 2.2–60). Surveillance period was 9.4 ± 6.7 years (range, 0.3–18.0). Satisfactory clinical improvements were noted immediately in all but two patients. Seventy-two (82.8%) patients were still alive with stable respiratory status, except two patients necessitating TFE management every two months. Fifty-one stents, including 35 tracheal and 16 bronchial ones, were successfully retrieved mainly with rigid endoscopy. Implanted stents could be significantly (stent diameters were positively correlated to the implanted duration. Altogether, 33 stents expired (15 patients), 51 were retrieved (40 patients), and 62 remained and functioning well (38 patients), with their mean duration of 7.4 ± 9.5, 34.9 ± 36.3 and 82.3 ± 62.5 months, respectively. Conclusion In pediatric patients, TFE with short-length scopes coupled with this NIV support has provided a safe, feasible and effective modality in placing and subsequently managing

  11. Nanoelectronics «bottom – up»: current generation, generalized Ohm’s law, elastic resistors, conductivity modes, thermoelectricity

    Directory of Open Access Journals (Sweden)

    Юрій Олексійович Кругляк

    2015-07-01

    Full Text Available General questions of electronic conductivity, current generation with the use of electrochemical potentials and Fermi functions, elastic resistor model, ballistic and diffusion transport, conductivity modes, n- and p-conductors and graphene, formulation of the generalized Ohm’s law, thermoelectric phenomena of Seebeck and Peltier, quality indicators and thermoelectric optimization, ballistic and diffusive phonon heat current are discussed in the frame of the «bottom – up» approach of modern nanoelectronics

  12. Flattened optical frequency-locked multi-carrier generation by cascading one DML and one phase modulator driven by different RF frequency clocks

    International Nuclear Information System (INIS)

    Li, Xinying; Yu, Jianjun; Zhang, Junwen; Chi, Nan

    2013-01-01

    We propose a novel scheme for flattened optical frequency-locked multi-carrier generation based on one directly modulated laser (DML) and one phase modulator (PM) in cascade driven by different sinusoidal radio-frequency (RF) clocks. We experimentally demonstrate that when the clock frequencies for the cascaded DML and the PM are respectively 12.5 GHz and 25 GHz, over 24 optical subcarriers can be generated with 12.5-GHz frequency spacing and amplitude fluctuation less than 3 dB. Furthermore, the number of generated optical subcarriers can be further increased when we increase the driving power for the DML. (letter)

  13. Optimal Energy Management of Multi-Microgrids with Sequentially Coordinated Operations

    Directory of Open Access Journals (Sweden)

    Nah-Oak Song

    2015-08-01

    Full Text Available We propose an optimal electric energy management of a cooperative multi-microgrid community with sequentially coordinated operations. The sequentially coordinated operations are suggested to distribute computational burden and yet to make the optimal 24 energy management of multi-microgrids possible. The sequential operations are mathematically modeled to find the optimal operation conditions and illustrated with physical interpretation of how to achieve optimal energy management in the cooperative multi-microgrid community. This global electric energy optimization of the cooperative community is realized by the ancillary internal trading between the microgrids in the cooperative community which reduces the extra cost from unnecessary external trading by adjusting the electric energy production amounts of combined heat and power (CHP generators and amounts of both internal and external electric energy trading of the cooperative community. A simulation study is also conducted to validate the proposed mathematical energy management models.

  14. A novel LabVIEW-based multi-channel non-invasive abdominal maternal-fetal electrocardiogram signal generator.

    Science.gov (United States)

    Martinek, Radek; Kelnar, Michal; Koudelka, Petr; Vanus, Jan; Bilik, Petr; Janku, Petr; Nazeran, Homer; Zidek, Jan

    2016-02-01

    This paper describes the design, construction, and testing of a multi-channel fetal electrocardiogram (fECG) signal generator based on LabVIEW. Special attention is paid to the fetal heart development in relation to the fetus' anatomy, physiology, and pathology. The non-invasive signal generator enables many parameters to be set, including fetal heart rate (FHR), maternal heart rate (MHR), gestational age (GA), fECG interferences (biological and technical artifacts), as well as other fECG signal characteristics. Furthermore, based on the change in the FHR and in the T wave-to-QRS complex ratio (T/QRS), the generator enables manifestations of hypoxic states (hypoxemia, hypoxia, and asphyxia) to be monitored while complying with clinical recommendations for classifications in cardiotocography (CTG) and fECG ST segment analysis (STAN). The generator can also produce synthetic signals with defined properties for 6 input leads (4 abdominal and 2 thoracic). Such signals are well suited to the testing of new and existing methods of fECG processing and are effective in suppressing maternal ECG while non-invasively monitoring abdominal fECG. They may also contribute to the development of a new diagnostic method, which may be referred to as non-invasive trans-abdominal CTG +  STAN. The functional prototype is based on virtual instrumentation using the LabVIEW developmental environment and its associated data acquisition measurement cards (DAQmx). The generator also makes it possible to create synthetic signals and measure actual fetal and maternal ECGs by means of bioelectrodes.

  15. The measurement of gas–liquid two-phase flows in a small diameter pipe using a dual-sensor multi-electrode conductance probe

    International Nuclear Information System (INIS)

    Zhai, Lu-Sheng; Bian, Peng; Han, Yun-Feng; Gao, Zhong-Ke; Jin, Ning-De

    2016-01-01

    We design a dual-sensor multi-electrode conductance probe to measure the flow parameters of gas–liquid two-phase flows in a vertical pipe with an inner diameter of 20 mm. The designed conductance probe consists of a phase volume fraction sensor (PVFS) and a cross-correlation velocity sensor (CCVS). Through inserting an insulated flow deflector in the central part of the pipe, the gas–liquid two-phase flows are forced to pass through an annual space. The multiple electrodes of the PVFS and the CCVS are flush-mounted on the inside of the pipe wall and the outside of the flow deflector, respectively. The geometry dimension of the PVFS is optimized based on the distribution characteristics of the sensor sensitivity field. In the flow loop test of vertical upward gas–liquid two-phase flows, the output signals from the dual-sensor multi-electrode conductance probe are collected by a data acquisition device from the National Instruments (NI) Corporation. The information transferring characteristics of local flow structures in the annular space are investigated using the transfer entropy theory. Additionally, the kinematic wave velocity is measured based on the drift velocity model to investigate the propagation behavior of the stable kinematic wave in the annular space. Finally, according to the motion characteristics of the gas–liquid two-phase flows, the drift velocity model based on the flow patterns is constructed to measure the individual phase flow rate with higher accuracy. (paper)

  16. Study of a PEFC power generator modular architecture based on a multi-stack association

    Energy Technology Data Exchange (ETDEWEB)

    Garnier, James; Pera, Marie-Cecile; Hissel, Daniel; Kauffmann, Jean-Marie [Laboratoire d' Electronique, Electrotechnique et Systemes, Unite Mixte de Recherche UTBM et UFC, L2ES-UTBM Batiment F-Technopole, Rue Thierry Mieg, 90010 Belfort (France); De Bernardinis, Alexandre; Candusso, Denis; Coquery, Gerard [Institut National de Recherche Sur Les Transports et Leur Securite (INRETS LTN), 2 Avenue Du General Malleret-Joinville, 94114 Arcueil (France)

    2006-05-19

    This paper presents a study of a polymer electrolyte fuel cell (PEFC) power generator based on a multi-stack association dedicated to transportation applications. First, a dynamic model of the fuel cell for high frequencies, which can be used in association with the power converter is presented. In a second hand, an original power converter architecture has been studied which authorizes the electrical association of two fuel cell stacks. Such a configuration is well adapted for the testing of fuel cell in normal or degraded mode which corresponds to real operating conditions encountered on-board a vehicle. Finally, simulation results of the complete twin-stacks power system are presented and discussed. (author)

  17. Multi-generational imputation of single nucleotide polymorphism marker genotypes and accuracy of genomic selection.

    Science.gov (United States)

    Toghiani, S; Aggrey, S E; Rekaya, R

    2016-07-01

    Availability of high-density single nucleotide polymorphism (SNP) genotyping platforms provided unprecedented opportunities to enhance breeding programmes in livestock, poultry and plant species, and to better understand the genetic basis of complex traits. Using this genomic information, genomic breeding values (GEBVs), which are more accurate than conventional breeding values. The superiority of genomic selection is possible only when high-density SNP panels are used to track genes and QTLs affecting the trait. Unfortunately, even with the continuous decrease in genotyping costs, only a small fraction of the population has been genotyped with these high-density panels. It is often the case that a larger portion of the population is genotyped with low-density and low-cost SNP panels and then imputed to a higher density. Accuracy of SNP genotype imputation tends to be high when minimum requirements are met. Nevertheless, a certain rate of genotype imputation errors is unavoidable. Thus, it is reasonable to assume that the accuracy of GEBVs will be affected by imputation errors; especially, their cumulative effects over time. To evaluate the impact of multi-generational selection on the accuracy of SNP genotypes imputation and the reliability of resulting GEBVs, a simulation was carried out under varying updating of the reference population, distance between the reference and testing sets, and the approach used for the estimation of GEBVs. Using fixed reference populations, imputation accuracy decayed by about 0.5% per generation. In fact, after 25 generations, the accuracy was only 7% lower than the first generation. When the reference population was updated by either 1% or 5% of the top animals in the previous generations, decay of imputation accuracy was substantially reduced. These results indicate that low-density panels are useful, especially when the generational interval between reference and testing population is small. As the generational interval

  18. First observation of multi-pulse X-ray train via multi-collision laser Compton scattering

    International Nuclear Information System (INIS)

    Kuroda, R.; Toyokawa, H.; Yasumoto, M.; Ikeura-Sekiguchi, H.; Koike, M.; Yamada, K.; Yanagida, T.; Nakajyo, T.; Sakai, F.

    2009-01-01

    A compact hard X-ray source via laser Compton scattering (LCS) has been developed for biological and medical applications at the National Institute of Advanced Industrial Science and Technology (AIST) in Japan. The multi-collision LCS has been investigated in order to enhance the X-ray yields. The first observation of multi-pulse X-ray train with 6 pulses via the multi-collision LCS has been successfully demonstrated between the multi-bunch electron train with 6 bunches and the multi-pulse Ti:Sa laser train with 6 pulses. The 32 MeV electron train was generated from a Cs 2 Te photocathode rf gun with a multi-pulse UV laser and the S-band linac. The Ti:Sa laser train was obtained with the chirp pulse amplification (CPA) including the modified regenerative amplifier. The X-ray train with 6 pulses with 12.6 ns spacing was observed with the micro-channel plate (MCP). The maximum energy of the X-ray is analytically estimated to be about 24 keV and the total number of generated photons was calculated to be about 1.8x10 6 photons/train.

  19. Using SMES as a multi-purpose interface in power generation, transmission and distribution systems

    International Nuclear Information System (INIS)

    Tam, K.S.; Zhang, X.; Yarali, A.

    1991-01-01

    This paper presents a new SMES schemes, the MSMES system, which significantly broadens the ways in which SMES can be applied to electric power systems. On the generation side, the SMES system can convert low-quality power into high-quality power and enhances the utilization of all energy sources available to the power systems. Acting both as an energy storage device and a power flow control device, a MSMES system can act as a hub in a power transmission system. The use of multiple MSMES systems can provide many new solutions to the problems facing the transmission networks of the United States today. On the distribution side, MSMES systems can be used as advanced power distribution centers that supply high-quality power to the customers while providing desirable load shapes to the power systems. In addition to these functions, a MSMES unit can also perform functions such as damping of power oscillation, stability and dynamic performance improvement and other recognized benefits of the conventional SMES system. Functioning as a multi-purpose power processing units, the MSMES systems improve the economics of SMES system. Functioning as a multi-purpose power processing units, the MSMES systems improve the economics of SMES technology and expand its potential market

  20. Multi-gigabit optical interconnects for next-generation on-board digital equipment

    Science.gov (United States)

    Venet, Norbert; Favaro, Henri; Sotom, Michel; Maignan, Michel; Berthon, Jacques

    2017-11-01

    Parallel optical interconnects are experimentally assessed as a technology that may offer the high-throughput data communication capabilities required to the next-generation on-board digital processing units. An optical backplane interconnect was breadboarded, on the basis of a digital transparent processor that provides flexible connectivity and variable bandwidth in telecom missions with multi-beam antenna coverage. The unit selected for the demonstration required that more than tens of Gbit/s be supported by the backplane. The demonstration made use of commercial parallel optical link modules at 850 nm wavelength, with 12 channels running at up to 2.5 Gbit/s. A flexible optical fibre circuit was developed so as to route board-to-board connections. It was plugged to the optical transmitter and receiver modules through 12-fibre MPO connectors. BER below 10-14 and optical link budgets in excess of 12 dB were measured, which would enable to integrate broadcasting. Integration of the optical backplane interconnect was successfully demonstrated by validating the overall digital processor functionality.

  1. Effect of conductance linearity and multi-level cell characteristics of TaOx-based synapse device on pattern recognition accuracy of neuromorphic system

    Science.gov (United States)

    Sung, Changhyuck; Lim, Seokjae; Kim, Hyungjun; Kim, Taesu; Moon, Kibong; Song, Jeonghwan; Kim, Jae-Joon; Hwang, Hyunsang

    2018-03-01

    To improve the classification accuracy of an image data set (CIFAR-10) by using analog input voltage, synapse devices with excellent conductance linearity (CL) and multi-level cell (MLC) characteristics are required. We analyze the CL and MLC characteristics of TaOx-based filamentary resistive random access memory (RRAM) to implement the synapse device in neural network hardware. Our findings show that the number of oxygen vacancies in the filament constriction region of the RRAM directly controls the CL and MLC characteristics. By adopting a Ta electrode (instead of Ti) and the hot-forming step, we could form a dense conductive filament. As a result, a wide range of conductance levels with CL is achieved and significantly improved image classification accuracy is confirmed.

  2. Skill, Judgement and Conduct for the First Generation of Neurosurgeons, 1900–1930

    Science.gov (United States)

    Gavrus, Delia

    2015-01-01

    Historical contingency complicates a reading of skill as a self-explanatory and always positive attribute. By focusing on the attempts of the first generation of neurosurgeons to build a community and fashion a collective neurosurgical self, this article highlights the extent to which the relationship between surgical skill and professional judgement is reflected in broader concerns that shape the landscape of medicine at a given time. Some early twentieth-century surgeons expressed concern about the spectacularisation of surgery and the skilful but problematic work of ‘brilliant operators’. The neurosurgeons’ policies of inclusion and exclusion show that in the process of fashioning a neurosurgical persona, this first generation sanctioned specific norms of conduct underwritten by similar moral imperatives, such as self-control. These norms governed the doctors’ work both in the operating room and on the public stage (in their engagement with the press). The meetings of the first neurosurgical society staged a critical encounter between the host neurosurgeon and the members who watched him perform surgery. These technical performances in the operating theatre, followed by discussions, were designed to encourage particular norms, to negotiate surgical knowledge, and to demonstrate the skills and character of the neurosurgeon. The performances acted as a technology of the self that aligned the operator to a community and helped that community refine its norms of surgical conduct. The awkward surgeon with inferior technical ability was preferable to the brilliant but vain operator who lacked the capacity to judge when he should not deploy his spectacular skills. PMID:26090734

  3. FEM Based Multi-Criterion Design and Implementation of a PM Synchronous Wind Generator by Fully Coupled Co-Simulation

    Directory of Open Access Journals (Sweden)

    OCAK, C.

    2018-02-01

    Full Text Available This study deals with analyzing, designing and fabricating of a 1 kW PM synchronous generator for gearless and direct drive off-grid wind turbines. Performance characteristics of this generator have been calculated analytically in collaboration with dynamic transient coupled-field analysis. All specifications of the PMSG have been investigated and optimized by using finite element method and parametric multi-criterion design approach. At the end of research, a prototype has been fabricated based on the optimized dimensions. Furthermore, the analytical calculations present along with experimental studies carried out for different shaft speeds and load levels. The comparative experimental studies have verified effectiveness of the optimized designing and dynamic co-simulations.

  4. Simulation-optimization framework for multi-site multi-season hybrid stochastic streamflow modeling

    Science.gov (United States)

    Srivastav, Roshan; Srinivasan, K.; Sudheer, K. P.

    2016-11-01

    able to predict the characteristics of the multi-site multi-season streamflows under uncertain future. Also, the AMHMABB model is found to perform better than the linear multi-site disaggregation model (MDM) in preserving the statistical as well as the multi-site critical deficit run characteristics of the observed flows. However, a major drawback of the hybrid models persists in case of the AMHMABB model as well, of not being able to synthetically generate enough number of flows beyond the observed extreme flows, and not being able to generate values that are quite different from the observed flows.

  5. Study of fast electron generation using multi beam of LFEX-class laser

    International Nuclear Information System (INIS)

    Hata, M; Nagatomo, H; Sakagami, H; Johzaki, T; Sentoku, Y

    2016-01-01

    Fast Ignition Realization Experiment project phase-I (FIREX-I) is being performed at Institute of Laser Engineering, Osaka University. In this project, the four-beam bundled high-energy Petawatt laser (LFEX) is being operated. LFEX laser provides great multi-beam irradiation flexibility, with the possibility of arrange the pulses in temporal sequence, spatially separate them in distinct spots of focus them in a single spot. In this paper, we study the two- beam interference effects on high-intensity picosecond laser-plasma interaction (LPI) by twodimensional relativistic Particle-In-Cell simulations. The interference causes surface perturbation, which enhances laser absorption and underdense plasma generation, increasing the accelerated electron number and their slope temperature. The laser-to-electron energy conversion efficiency for two-beam interference case is suitable for Fast Ignition (FI) compared to the single beam case, but the increment of fast electron divergence leads to lower energy coupling. To optimize the target design for FI, these interference effects should be taken into consideration. (paper)

  6. MULTI SENSOR DATA INTEGRATION FOR AN ACCURATE 3D MODEL GENERATION

    Directory of Open Access Journals (Sweden)

    S. Chhatkuli

    2015-05-01

    Full Text Available The aim of this paper is to introduce a novel technique of data integration between two different data sets, i.e. laser scanned RGB point cloud and oblique imageries derived 3D model, to create a 3D model with more details and better accuracy. In general, aerial imageries are used to create a 3D city model. Aerial imageries produce an overall decent 3D city models and generally suit to generate 3D model of building roof and some non-complex terrain. However, the automatically generated 3D model, from aerial imageries, generally suffers from the lack of accuracy in deriving the 3D model of road under the bridges, details under tree canopy, isolated trees, etc. Moreover, the automatically generated 3D model from aerial imageries also suffers from undulated road surfaces, non-conforming building shapes, loss of minute details like street furniture, etc. in many cases. On the other hand, laser scanned data and images taken from mobile vehicle platform can produce more detailed 3D road model, street furniture model, 3D model of details under bridge, etc. However, laser scanned data and images from mobile vehicle are not suitable to acquire detailed 3D model of tall buildings, roof tops, and so forth. Our proposed approach to integrate multi sensor data compensated each other’s weakness and helped to create a very detailed 3D model with better accuracy. Moreover, the additional details like isolated trees, street furniture, etc. which were missing in the original 3D model derived from aerial imageries could also be integrated in the final model automatically. During the process, the noise in the laser scanned data for example people, vehicles etc. on the road were also automatically removed. Hence, even though the two dataset were acquired in different time period the integrated data set or the final 3D model was generally noise free and without unnecessary details.

  7. The third generation multi-purpose plasma immersion ion implanter for surface modification of materials

    CERN Document Server

    Tang Bao Yin; Wang Xiao Feng; Gan Kong Yin; Wang Song Yan; Chu, P K; Huang Nian Ning; Sun Hong

    2002-01-01

    The third generation multi-purpose plasma immersion ion implantation (PIII) equipment has been successfully used for research and development of surface modification of biomedical materials, metals and their alloys in the Southwest Jiaotong University. The implanter equipped with intense current, pulsed cathodic arc metal plasma sources which have both strong coating function and gas and metal ion implantation function. Its pulse high voltage power supply can provide big output current. It can acquire very good implantation dose uniformity. The equipment can both perform ion implantation and combine ion implantation with sputtering deposition and coating to form many kinds of synthetic surface modification techniques. The main design principles, features of important components and achievement of research works in recent time have been described

  8. A method for aggregating external operating conditions in multi-generation system optimization models

    DEFF Research Database (Denmark)

    Lythcke-Jørgensen, Christoffer Ernst; Münster, Marie; Ensinas, Adriano Viana

    2016-01-01

    This paper presents a novel, simple method for reducing external operating condition datasets to be used in multi-generation system optimization models. The method, called the Characteristic Operating Pattern (CHOP) method, is a visually-based aggregation method that clusters reference data based...... on parameter values rather than time of occurrence, thereby preserving important information on short-term relations between the relevant operating parameters. This is opposed to commonly used methods where data are averaged over chronological periods (months or years), and extreme conditions are hidden...... in the averaged values. The CHOP method is tested in a case study where the operation of a fictive Danish combined heat and power plant is optimized over a historical 5-year period. The optimization model is solved using the full external operating condition dataset, a reduced dataset obtained using the CHOP...

  9. Multi-wavelength Brillouin Raman erbium-doped fiber laser generation in a linear cavity

    International Nuclear Information System (INIS)

    Shirazi, M R; Harun, S W; Ahmad, H

    2014-01-01

    A multi-wavelength Brillouin Raman erbium-doped fiber laser is proposed and demonstrated. The setup uses a 7.7 km dispersion compensating fiber simultaneously as the Brillouin and Raman nonlinear gain media and operates in conjunction with a 3 m erbium-doped fiber as the linear gain medium. At a Brillouin pump (BP) wavelength of 1530 nm, where Raman and erbium gains overlap each other, 34 Brillouin Stokes lines having line spacing of 0.075 nm are created by using a Raman pump power of only 24.1 dBm, an erbium pump power of about 22.1 dBm, and a BP power of 6.5 dBm in the proposed linear cavity. The system is highly efficient and is able to generate many comparable peak-power lines at a low pump power. (paper)

  10. Multi-objective Generation Expansion Planning for Integrating Largescale Wind Generation

    DEFF Research Database (Denmark)

    Zhang, Chunyu; Ding, Yi; Kang, Chongqing

    2013-01-01

    Due to the growth of energy consumption, the extensive use of conventional fossil fuels from the exhaustible resources and the environmental concerns, high penetration of renewable energy resources is considerably observed worldwide. Wind power generation is holding the first rank in terms...... of utilization and importance. In the last decade, the growth rate of the global installed wind capacity has been about 30% per annum. Denmark, Germany, and Spain are the first few countries generating 20% of their electricity from wind turbines....

  11. Third-generation intelligent IR focal plane arrays

    Science.gov (United States)

    Caulfield, H. John; Jack, Michael D.; Pettijohn, Kevin L.; Schlesselmann, John D.; Norworth, Joe

    1998-03-01

    SBRC is at the forefront of industry in developing IR focal plane arrays including multi-spectral technology and '3rd generation' functions that mimic the human eye. 3rd generation devices conduct advanced processing on or near the FPA that serve to reduce bandwidth while performing needed functions such as automatic target recognition, uniformity correction and dynamic range enhancement. These devices represent a solution for processing the exorbitantly high bandwidth coming off large area FPAs without sacrificing systems sensitivity. SBRC's two-color approach leverages the company's HgCdTe technology to provide simultaneous multiband coverage, from short through long wave IR, with near theoretical performance. IR systems that are sensitive to different spectral bands achieve enhanced capabilities for target identification and advanced discrimination. This paper will provide a summary of the issues, the technology and the benefits of SBRC's third generation smart and two-color FPAs.

  12. Multi-time scale energy management of wind farms based on comprehensive evaluation technology

    Science.gov (United States)

    Xu, Y. P.; Huang, Y. H.; Liu, Z. J.; Wang, Y. F.; Li, Z. Y.; Guo, L.

    2017-11-01

    A novel energy management of wind farms is proposed in this paper. Firstly, a novel comprehensive evaluation system is proposed to quantify economic properties of each wind farm to make the energy management more economical and reasonable. Then, a combination of multi time-scale schedule method is proposed to develop a novel energy management. The day-ahead schedule optimizes unit commitment of thermal power generators. The intraday schedule is established to optimize power generation plan for all thermal power generating units, hydroelectric generating sets and wind power plants. At last, the power generation plan can be timely revised in the process of on-line schedule. The paper concludes with simulations conducted on a real provincial integrated energy system in northeast China. Simulation results have validated the proposed model and corresponding solving algorithms.

  13. CASKETSS-HEAT: a finite difference computer program for nonlinear heat conduction problems

    International Nuclear Information System (INIS)

    Ikushima, Takeshi

    1988-12-01

    A heat conduction program CASKETSS-HEAT has been developed. CASKETSS-HEAT is a finite difference computer program used for the solution of multi-dimensional nonlinear heat conduction problems. Main features of CASKETSS-HEAT are as follows. (1) One, two and three-dimensional geometries for heat conduction calculation are available. (2) Convection and radiation heat transfer of boundry can be specified. (3) Phase change and chemical change can be treated. (4) Finned surface heat transfer can be treated easily. (5) Data memory allocation in the program is variable according to problem size. (6) The program is a compatible heat transfer analysis program to the stress analysis program SAP4 and SAP5. (7) Pre- and post-processing for input data generation and graphic representation of calculation results are available. In the paper, brief illustration of calculation method, input data and sample calculation are presented. (author)

  14. Multi-Touch Tablets, E-Books, and an Emerging Multi-Coding/Multi-Sensory Theory for Reading Science E-Textbooks: Considering the Struggling Reader

    Science.gov (United States)

    Rupley, William H.; Paige, David D.; Rasinski, Timothy V.; Slough, Scott W.

    2015-01-01

    Pavio's Dual-Coding Theory (1991) and Mayer's Multimedia Principal (2000) form the foundation for proposing a multi-coding theory centered around Multi-Touch Tablets and the newest generation of e-textbooks to scaffold struggling readers in reading and learning from science textbooks. Using E. O. Wilson's "Life on Earth: An Introduction"…

  15. Investigations of the tracheobronchial epithelium of rat after X-ray irradiation and inhalation of 212Pb aerosol

    International Nuclear Information System (INIS)

    Petri, P.

    1981-01-01

    Early reactions of the tracheobronchial epithelium of rats. Be up to 96 h after irradiation have been investigated. Detection of autoradiographically labelled DNA in the basal cells is a measure of the regenerative function of the epithelium. The labelling index is determined on the basis of histological preparations of trachea and bronchi. Each group of animals was exposed to partial irradiation of the thorax of 500 R, 1000 R and 1500 R. A dose-dependent reduction of the labelling index is found with a minimum after 24 h. A further group of animals inhaled 212 Pb aerosol while the control group was given inactive aerosol. The calculations of Hofmann (1969) yield a value of about 170 rad for the trachea and 480 rad for the upper part of the lungs. The labelling index after 12 h is lower than in the animals exposed to 500 R. It is significantly higher in the lobar bronchi. At the time of sacrificing, the labelling index is higher in all regions than the labelling index of 500 R animals. This labelling method enables quantitative determination of DNA synthesis and labelling index after radiation exposure. The study did not indicate the stage of development in which the so-called ''replacement cells'' of the bronchial epithelium are influenced by radiation exposure. Radionuclide inhalation does not affect the bronchial DNA synthesis index as strongly as assumed on the basis of dose estimates. Ater 12 h, the trachea shows a stronger reaction than the bronchi. Explanations are offered. (orig./MG) [de

  16. Generational Differences in Work Attitudes : A comparative analysis of Generation Y and preceding generations from companies in Sweden

    OpenAIRE

    Sajjadi, Amir; Åkesson Castillo, Lars Christian Felipe; Sun, Bicen

    2012-01-01

    Introduction: A population that can live and work longer has resulted in a wider range of generations being active in the workplace simultaneously and the diverse multi-generational work environment is a new challenge for human resource management. The most recent generation that is entering the job market is Generation Y, which is also referred to as Millennials. Currently, organizations and Human Resource departments are facing the issue of Generation Y entering the workforce and the issue ...

  17. Multi-chamber and multi-layer thiol-ene microchip for cell culture

    DEFF Research Database (Denmark)

    Tan, H. Y.; Hemmingsen, Mette; Lafleur, Josiane P.

    2014-01-01

    We present a multi-layer and multi-chamber microfluidic chip fabricated using two different thiol-ene mixtures. Sandwiched between the thiol-ene chip layers is a commercially available membrane whose morphology has been altered with coatings of thiol-ene mixtures. Experiments have been conducted ...... with the microchip and shown that the fabricated microchip is suitable for long term cell culture....

  18. Multi-attribute criteria applied to electric generation energy system analysis LDRD.

    Energy Technology Data Exchange (ETDEWEB)

    Kuswa, Glenn W.; Tsao, Jeffrey Yeenien; Drennen, Thomas E.; Zuffranieri, Jason V.; Paananen, Orman Henrie; Jones, Scott A.; Ortner, Juergen G. (DLR, German Aerospace, Cologne); Brewer, Jeffrey D.; Valdez, Maximo M.

    2005-10-01

    This report began with a Laboratory-Directed Research and Development (LDRD) project to improve Sandia National Laboratories multidisciplinary capabilities in energy systems analysis. The aim is to understand how various electricity generating options can best serve needs in the United States. The initial product is documented in a series of white papers that span a broad range of topics, including the successes and failures of past modeling studies, sustainability, oil dependence, energy security, and nuclear power. Summaries of these projects are included here. These projects have provided a background and discussion framework for the Energy Systems Analysis LDRD team to carry out an inter-comparison of many of the commonly available electric power sources in present use, comparisons of those options, and efforts needed to realize progress towards those options. A computer aid has been developed to compare various options based on cost and other attributes such as technological, social, and policy constraints. The Energy Systems Analysis team has developed a multi-criteria framework that will allow comparison of energy options with a set of metrics that can be used across all technologies. This report discusses several evaluation techniques and introduces the set of criteria developed for this LDRD.

  19. Confirming nasogastric tube placement: Is the colorimeter as sensitive and specific as X-ray? A diagnostic accuracy study.

    Science.gov (United States)

    Mordiffi, Siti Zubaidah; Goh, Mien Li; Phua, Jason; Chan, Yiong-Huak

    2016-09-01

    The effect of delivering enteral nutrition or medications via a nasogastric tube that is inadvertently located in the tracheobronchial tract can cause respiratory complications. Although radiographic examination is accepted as the gold standard for confirming the position of patients' enteral tubes, it is costly, involves risks of radiation, and is not failsafe. Studies using carbon dioxide sensors to detect inadvertent nasogastric tube placements have been conducted in intensive care settings. However, none involved patients in general wards. The objective of this study was to ascertain the diagnostic measure of colorimeter, with radiographic examination as the reference standard, to confirm the location of nasogastric tubes in patients. A prospective observational study of a diagnostic test. This study was conducted in the general wards of an approximately 1100-bed acute care tertiary hospital of an Academic Medical Center in Singapore. Adult patients with nasogastric tubes admitted to the general wards were recruited into the study. The colorimeter was attached to the nasogastric tube to detect for the presence of carbon dioxide, suggestive of a tracheobronchial placement. The exact location of the nasogastric tube was subsequently confirmed by a radiographic examination. A total of 192 tests were undertaken. The colorimeter detected carbon dioxide in 29 tested nasogastric tubes, of which radiographic examination confirmed that four tubes were located in the tracheobronchial tract. The colorimeter failed to detect carbon dioxide in one nasogastric tube that was located in the tracheobronchial tract, thus, demonstrating a sensitivity of 0.80 [95% CI (0.376, 0.964)]. The colorimeter detected absence of carbon dioxide in 163 tested nasogastric tubes in which radiographic examination confirmed 160 gastrointestinal and one tracheobronchial placements, demonstrating a specificity of 0.865 [95% CI (0.808, 0.907)]. The colorimeter detected one tracheobronchial

  20. The application of spiral-CT and 3D-imaging of airway for observation of efficacy and complication after tracheobronchial stent placement

    International Nuclear Information System (INIS)

    Wei Ning; Xu Hao; Zu Maoheng; Gu Yuming; Li Gang; Zhang Qingqiao; Xu Wei; Cui Yanfeng; Liu Hongtao; Wang Wenliang

    2012-01-01

    Objective: To evaluate the application of spiral-CT and 3D-imaging of airway for observation of efficacy and complication after tracheobronchial stent placement. Methods: Thirty-one patients treated with tracheal stents were retrospectively analyzed, of which there were 27 malignant tracheal stenosis, 2 benign tracheal stenosis, 1 bronchial remnant fistula and 1 gastroesophageal anastomosis tracheal fistula. The spiral-CT and 3D-imagings were analyzed and the location, shape and complication of the stents were assessed. Results: Thirty-one patients were treated with 8 Z-type stainless steel stents and 28 Ni-Ti memory alloy stents. The stents of 22 cases remained patent in the original position and restenosis was occurred in 5 cases, migration in 3 cases and fracture in 1 case. All the CT features were performed and reconstructed on the workstation, using multiplanar reconstruction, volume rendering, and CT virtual endoscopy. The location of tracheal stenosis and fistula were showed in different angle, and the location, shape of the stents, and the complications (such as restenosis, fracture) as well. Conclusion: Spiral-CT and 3D-imaging is a rapid, simple and effective method in assessing tracheal stent implantation and complication, therefore, it is of great value in clinical practice. (authors)

  1. Modified Multi Prime RSA Cryptosystem

    Science.gov (United States)

    Ghazali Kamardan, M.; Aminudin, N.; Che-Him, Norziha; Sufahani, Suliadi; Khalid, Kamil; Roslan, Rozaini

    2018-04-01

    RSA [1] is one of the mostly used cryptosystem in securing data and information. Though, it has been recently discovered that RSA has some weaknesses and in advance technology, RSA is believed to be inefficient especially when it comes to decryption. Thus, a new algorithm called Multi prime RSA, an extended version of the standard RSA is studied. Then, a modification is made to the Multi prime RSA where another keys is shared secretly between the receiver and the sender to increase the securerity. As in RSA, the methodology used for modified Multi-prime RSA also consists of three phases; 1. Key Generation in which the secret and public keys are generated and published. In this phase, the secrecy is improved by adding more prime numbers and addition of secret keys. 2. Encryption of the message using the public and secret keys given. 3. Decryption of the secret message using the secret key generated. For the decryption phase, a method called Chinese Remainder Theorem is used which helps to fasten the computation. Since Multi prime RSA use more than two prime numbers, the algorithm is more efficient and secure when compared to the standard RSA. Furthermore, in modified Multi prime RSA another secret key is introduced to increase the obstacle to the attacker. Therefore, it is strongly believed that this new algorithm is better and can be an alternative to the RSA.

  2. A tapped-inductor buck-boost converter for a multi-DEAP generator energy harvesting system

    DEFF Research Database (Denmark)

    Dimopoulos, Emmanouil; Munk-Nielsen, Stig

    2014-01-01

    the effective operational range of the power electronic converter. In this paper, a bidirectional tapped-inductor buck-boost converter is proposed, addressing high-efficient high step-up and high step-down voltage conversion ratios, for energy harvesting applications based on DEAP generators. The effective...... operational range of the converter is extended, by replacing its high-side switch with a string of three serialized MOSFETs, to accommodate the need for high-efficient high-voltage operation. Experiments conducted on a single DEAP generator - part of a quadruple DEAP generator energy harvesting system...... with all elements installed sequentially in the same circular disk with a 90 phase shift - validate the applicability of the proposed converter, demonstrating energy harvesting of 0.26 J, at 0.5 Hz and 60 % delta-strain; characterized by an energy density of 1.25 J per kg of active material....

  3. MIMO wireless networks channels, techniques and standards for multi-antenna, multi-user and multi-cell systems

    CERN Document Server

    Clerckx, Bruno

    2013-01-01

    This book is unique in presenting channels, techniques and standards for the next generation of MIMO wireless networks. Through a unified framework, it emphasizes how propagation mechanisms impact the system performance under realistic power constraints. Combining a solid mathematical analysis with a physical and intuitive approach to space-time signal processing, the book progressively derives innovative designs for space-time coding and precoding as well as multi-user and multi-cell techniques, taking into consideration that MIMO channels are often far from ideal. Reflecting developments

  4. Depth analysis of mechanically machined flaws on steam generator tubings using multi-parameter algorithm

    International Nuclear Information System (INIS)

    Nam Gung, Chan; Lee, Yoon Sang; Hwang, Seong Sik; Kim, Hong Pyo

    2004-01-01

    The eddy current testing (ECT) is a nondestructive technique. It is used for evaluation of material's integrity, especially, steam generator (SG) tubing in nuclear plants, due to their rapid inspection, safe and easy operation. For depth measurement of defects, we prepared Electro Discharge Machined (EDM) notches that have several of defects and applied multi-parameter (MP) algorithm. It is a crack shape estimation program developed in Argonne National Laboratory (ANL). To evaluate the MP algorithm, we compared defect profile with fractography of the defects. In the following sections, we described the basic structure of a computer-aided data analysis algorithm used as means of more accurate and efficient processing of ECT data, and explained the specification of a standard calibration. Finally, we discussed the accuracy of estimated depth profile compared with conventional ECT method

  5. Multi-agent based controller for islanding operation of active distribution networks with distributed generation

    DEFF Research Database (Denmark)

    Cha, Seung-Tae; Wu, Qiuwei; Østergaard, Jacob

    2011-01-01

    -bus system was used to investigate the dynamic and steady state performance of the active distribution system during islanding operation. Case studies have been carried out using the Real-Time Digital Simulator (RTDS) based simulation platform. Case study results show that the proposed multi......The increasing amount of distributed generation (DG) in today’s highly complex restructured power networks gives more options for distribution system operators (DSOs) under contingency conditions. A low voltage distribution network with a large amount of DG can be operated as an islanded system...... if the distribution system is disconnected from the main grid due to the contingency. In order to successfully operate distribution systems under islanding mode, the possibility of small power islands within the distribution system needs to be considered. The control and management of these small power islands...

  6. Discovery of high-performance low-cost n-type Mg3Sb2-based thermoelectric materials with multi-valley conduction bands

    DEFF Research Database (Denmark)

    Zhang, Jiawei; Song, Lirong; Pedersen, Steffen Hindborg

    2017-01-01

    Widespread application of thermoelectric devices for waste heat recovery requires low-cost high-performance materials. The currently available n-type thermoelectric materials are limited either by their low efficiencies or by being based on expensive, scarce or toxic elements. Here we report a low-cost...... because of the multi-valley band behaviour dominated by a unique near-edge conduction band with a sixfold valley degeneracy. This makes Te-doped Mg3Sb1.5Bi0.5 a promising candidate for the low- and intermediate-temperature thermoelectric applications....

  7. Negative voltage modulated multi-level resistive switching by using a Cr/BaTiOx/TiN structure and quantum conductance through evidence of H2O2 sensing mechanism.

    Science.gov (United States)

    Chakrabarti, Somsubhra; Ginnaram, Sreekanth; Jana, Surajit; Wu, Zong-Yi; Singh, Kanishk; Roy, Anisha; Kumar, Pankaj; Maikap, Siddheswar; Qiu, Jian-Tai; Cheng, Hsin-Ming; Tsai, Ling-Na; Chang, Ya-Ling; Mahapatra, Rajat; Yang, Jer-Ren

    2017-07-05

    Negative voltage modulated multi-level resistive switching with quantum conductance during staircase-type RESET and its transport characteristics in Cr/BaTiO x /TiN structure have been investigated for the first time. The as-deposited amorphous BaTiO x film has been confirmed by high-resolution transmission electron microscopy. X-ray photo-electron spectroscopy shows different oxidation states of Ba in the switching material, which is responsible for tunable more than 10 resistance states by varying negative stop voltage owing to slow decay value of RESET slope (217.39 mV/decade). Quantum conductance phenomenon has been observed in staircase RESET cycle of the memory devices. By inspecting the oxidation states of Ba + and Ba 2+ through measuring H 2 O 2 with a low concentration of 1 nM in electrolyte/BaTiO x /SiO 2 /p-Si structure, the switching mechanism of each HRS level as well as the multi-level phenomenon has been explained by gradual dissolution of oxygen vacancy filament. Along with negative stop voltage modulated multi-level, current compliance dependent multi-level has also been demonstrated and resistance ratio up to 2000 has been achieved even for a thin (voltage switching curve has been simulated as well. Hence, multi-level resistive switching of Cr/BaTiO x /TiN structure implies the promising applications in high dense, multistate non-volatile memories in near future.

  8. High thermal conductivity materials for thermal management applications

    Science.gov (United States)

    Broido, David A.; Reinecke, Thomas L.; Lindsay, Lucas R.

    2018-05-29

    High thermal conductivity materials and methods of their use for thermal management applications are provided. In some embodiments, a device comprises a heat generating unit (304) and a thermally conductive unit (306, 308, 310) in thermal communication with the heat generating unit (304) for conducting heat generated by the heat generating unit (304) away from the heat generating unit (304), the thermally conductive unit (306, 308, 310) comprising a thermally conductive compound, alloy or composite thereof. The thermally conductive compound may include Boron Arsenide, Boron Antimonide, Germanium Carbide and Beryllium Selenide.

  9. Multi-Objective Distribution Network Operation Based on Distributed Generation Optimal Placement Using New Antlion Optimizer Considering Reliability

    Directory of Open Access Journals (Sweden)

    KHANBABAZADEH Javad

    2016-10-01

    Full Text Available Distribution network designers and operators are trying to deliver electrical energy with high reliability and quality to their subscribers. Due to high losses in the distribution systems, using distributed generation can improves reliability, reduces losses and improves voltage profile of distribution network. Therefore, the choice of the location of these resources and also determining the amount of their generated power to maximize the benefits of this type of resource is an important issue which is discussed from different points of view today. In this paper, a new multi-objective optimal location and sizing of distributed generation resources is performed to maximize its benefits on the 33 bus distribution test network considering reliability and using a new Antlion Optimizer (ALO. The benefits for DG are considered as system losses reduction, system reliability improvement and benefits from the sale electricity and voltage profile improvement. For each of the mentioned benefits, the ALO algorithm is used to optimize the location and sizing of distributed generation resources. In order to verify the proposed approach, the obtained results have been analyzed and compared with the results of particle swarm optimization (PSO algorithm. The results show that the ALO has shown better performance in optimization problem solution versus PSO.

  10. Final Scientific/Technical Report (DOE F 241.3) Next-Generation LED Package Architectures Enabled by Thermally Conductive Transparent Encapsulants

    Energy Technology Data Exchange (ETDEWEB)

    Murugaiah, Anand [Momentive Performance Materials Quartz, Inc., Strongsville, OH (United States)

    2016-12-30

    The objective of this program is to generate novel LED package designs that would provide 30% improvement in lumen/$ output. This was to be achieved by improving thermal management in encapsulants/ phosphors to reduce their temperatures. Currently, the heat that is generated during down conversion of blue light to longer wavelengths by the phosphors dispersed in the encapsulant does not have optimum thermal pathways for dissipation due to poor thermal conductivity of the encapsulant material. Additionally, high temperature in the encapsulant during operation is one of the primary failure modes in LED luminaires resulting in much shorter than expected life. The thermal issues manifest in color instability (yellowing, browning), cracking and hot spots in the encapsulant leading to failures. This work explored boron nitride (hBN) as thermal fillers in encapsulants to improve thermal conductivity while minimally impacting optical properties. Various approaches to Boron Nitride (BN) were evaluated and over 380 samples were generated to down select appropriate BN morphologies. We developed a range or BN materials for enabling thermal properties while attempting to minimally impact to optical properties.

  11. Electrical conductivity of hydrogen shocked to megabar pressures

    International Nuclear Information System (INIS)

    Weir, S.T.; Nellis, W.J.; Mitchell, A.C.

    1993-08-01

    The properties of ultra-high pressure hydrogen have been the subject of much experimental and theoretical study. Of particular interest is the pressure-induced insulator-to-metal transition of hydrogen which, according to recent theoretical calculations, is predicted to occur by band-overlap in the pressure range of 1.5-3.0 Mbars on the zero temperature isotherm. Extremely high pressures are required for metallization since the low-pressure band gap is about 15 eV. Recent static-pressure diamond anvil cell experiments have searched for evidence of an insulator-to-metal transition, but no conclusive evidence for such a transition has yet been supplied. Providing conclusive evidence for hydrogen metallization is difficult because no technique has yet been developed for performing static high-pressure electrical conductivity experiments at megabar pressures. The authors report here on electrical conductivity experiments performed on H 2 and D 2 multi-shocked to megabar pressures. Electrical conductivities of dense fluid hydrogen at these pressures and temperatures reached are needed for calculations of the magnetic fields of Jupiter and Saturn, the magnetic fields being generated by convective dynamos of hot, dense, semiconducting fluid hydrogen. Also, since electrical conduction at the pressure-temperature conditions being studied is due to the thermal excitation of charge carriers across the electronic band gap, these experiments yield valuable information on the width of the band gap at high densities

  12. Improvement of thermal conductivity of ceramic matrix composites for 4. generation nuclear reactors

    International Nuclear Information System (INIS)

    Cabrero, J.

    2009-11-01

    This study deals with thermal conductivity improvement of SiCf/SiC ceramic matrix composites materials to be used as cladding material in 4. generation nuclear reactor. The purpose of the study is to develop a composite for which both the temperature and irradiation effect is less pronounced on thermal conductivity of material than for SiC. This material will be used as matrix in CMC with SiC fibers. Some TiC-SiC composites with different SiC volume contents were prepared by spark plasma sintering (SPS). The sintering process enables to fabricate specimens very fast, with a very fine microstructure and without any sintering aids. Neutron irradiation has been simulated using heavy ions, at room temperature and at 500 C. Evolution of the thermal properties of irradiated materials is measured using modulated photothermal IR radiometry experiment and was related to structural evolution as function of dose and temperature. It appears that such approach is reliable to evaluate TiC potentiality as matrix in CMC. Finally, CMC with TiC matrix and SiC fibers were fabricated and both mechanical and thermal properties were measured and compare to SiCf/SiC CMC. (author)

  13. Tuning the optical bandgap in multi-cation compound transparent conducting-oxides: The examples of In2ZnO4 and In4Sn3O12

    Science.gov (United States)

    Sabino, Fernando P.; Oliveira, Luiz N.; Wei, Su-Huai; Da Silva, Juarez L. F.

    2018-02-01

    Transparent conducting oxides such as the bixbyite In2O3 and rutile SnO2 systems have large disparities between the optical and fundamental bandgaps, ΔEgO F , because selection rules forbid dipolar transitions from the top of the valence band to the conduction-band minimum; however, the optical gaps of multi-cation compounds with the same chemical species often coincide with their fundamental gaps. To explain this conundrum, we have employed density-functional theory to compute the optical properties of multi-cation compounds, In2ZnO4 and In4Sn3O12, in several crystal structures. We show that a recently proposed mechanism to explain the disparity between the optical and fundamental gaps of M2O3 (M = Al, Ga, and In) applies also to other binary systems and to multi-compounds. Namely, a gap disparity will arise if the following three conditions are satisfied: (i) the crystal structure has inversion symmetry; (ii) the conduction-band minimum is formed by the cation and O s-orbitals; and (iii) there is strong p-d coupling and weak p-p in the vicinity of the valence-band maximum. The third property depends critically on the cationic chemical species. In the structures with inversion symmetry, Zn (Sn) strengthens (weakens) the p-d coupling in In2ZnO4 (In4Sn3O12), enhancing (reducing) the gap disparity. Furthermore, we have also identified a In4Sn3O12 structure that is 31.80 meV per formula unit more stable than a recently proposed alternative model.

  14. Design of multi-function Hanford tank corrosion monitoring system

    International Nuclear Information System (INIS)

    EDGEMON, G.L.

    1999-01-01

    A multi-fiction corrosion monitoring system has been designed for installation into DST 241-AN-105 at the Hanford Site in fiscal year 1999. The 241-AN-105 system is the third-generation corrosion monitoring system described by TTP RLO-8-WT-21. Improvements and upgrades from the second-generation system (installed in 241-AN-102) that have been incorporated into the third-generation system include: Gasket seating surfaces utilize O-rings instead of a washer type gasket for improved seal; Probe design contains an equally spaced array of 22 thermocouples; Probe design contains an adjustable verification thermocouple; Probe design contains three ports for pressure/gas sampling; Probe design contains one set of strain gauges to monitor probe flexure if flexure occurs; Probe utilizes an adjustable collar to allow depth adjustment of probe during installation; System is capable of periodically conducting LPR scans; System is housed in a climate controlled enclosure adjacent to the riser containing the probe; System uses wireless Ethernet links to send data to Hanford Local Area Network; System uses commercial remote access software to allow remote command and control; and Above ground wiring uses driven shields to reduce external electrostatic noise in the data. These new design features have transformed what was primarily a second-generation corrosion monitoring system into a multi-function tank monitoring system that adds a great deal of functionality to the probe, provides for a better understanding of the relationship between corrosion and other tank operating parameters, and optimizes the use of the riser that houses the probe in the tank

  15. A novel thick-film electrical conductivity sensor suitable for liquid and soil conductivity measurements

    OpenAIRE

    Atkinson, John; Sophocleous, Marios

    2015-01-01

    Results are reported from an initial evaluation of a novel conductivity sensor that could be incorporated onto a multi-element thick film (screen printed) sensor array designed for soil and water analysis. The new sensor exhibits a repeatable cell constant over a wide range of conductivities and is currently performing very well in an investigation of soil structural properties where its output is being correlated with soil water content in a study of different soil porosities.

  16. Orthogonal Test Analysis on Conditions Affecting Electricity Generation Performance of an Enhanced Geothermal System at Yangbajing Geothermal Field

    Directory of Open Access Journals (Sweden)

    Yuchao Zeng

    2017-12-01

    Full Text Available The main conditions affecting electricity generation performance of an enhanced geothermal system (EGS include reservoir porosity, reservoir permeability, rock heat conductivity, water production rate and injection temperature. Presently there is lack of systematic research the relative importance of the five aforementioned conditions. The orthogonal test method is a statistical approach to analyze multi-factor and multi-level influence on system performance. In this work, based on the geological data at Yangbajing geothermal field, we analyzed the five conditions affecting the electricity generation performance of EGS, and ranked the relative importance of the five factors. The results show that the order of the relative importance of the conditions on electric power is water production rate > injection temperature > reservoir porosity > rock heat conductivity > reservoir permeability; the order of the relative importance of the conditions on reservoir impedance is reservoir permeability > injection temperature > water production rate > reservoir porosity > rock heat conductivity; the order of the relative importance of the conditions on pump power is water production rate > reservoir permeability > injection temperature > reservoir porosity > rock heat conductivity, and; the order of the relative importance of the conditions on energy efficiency is water production rate > reservoir permeability > reservoir porosity > injection temperature > rock heat conductivity. The construction of an EGS reservoir should be located at a formation with higher reservoir porosity or rock heat conductivity, while the determination of reservoir permeability, water production rate and injection temperature should be based on the comprehensive target.

  17. Effect of cross-linkable polymer on the morphology and properties of transparent multi-walled carbon nanotube conductive films

    International Nuclear Information System (INIS)

    Huang, Yuan-Li; Tien, Hsi-Wen; Ma, Chen-Chi M.; Teng, Chih-Chun; Yu, Yi-Hsiuan; Yang, Shin-Yi; Wei, Ming-Hsiung; Wu, Sheng-Yen

    2011-01-01

    In this study, we fabricated optically transparent and electrically conductive multi-walled carbon nanotube (MWCNT) thin films using a spray-coating technique. The transparency and the electrical resistance of thin film are dependent on the nanotube content deposited on the polyethylene terephthalate (PET) substrate. Poly(acrylic acid) (PAA) and poly(N-vinyl pyrrolidone) (PVP) were used as adhesion promoters to improve MWCNT coating more significantly. The cross-linked polymer resulted in a superior bond between the MWCNTs and the substrates. The surface electrical resistance was significantly lower than the original sheet after nitric acid (HNO 3 ) treatment because of the removed surfactant and the increased interconnecting networks of MWCNT bundles, thus improving the electrical and optical properties of the films. Stronger interaction between the MWCNTs and the substrates resulted in lower decomposition of the polymer chain and less amounts of MWCNTs separated into the HNO 3 solution. The lower sheet electrical resistance of PVP/PAA-g-MWCNT conductive films on the PET substrate was because of a more complete conductive path with the cross-linked polymer than that without. Such an improved sheet of electrical resistance varied from 8.83 x 10 4 Ω/□ to 2.65 x 10 3 Ω/□ with 5.0 wt.% PVP/PAA-g-MWCNT sprayed on the PET after acid treatment.

  18. Effect of cross-linkable polymer on the morphology and properties of transparent multi-walled carbon nanotube conductive films

    Science.gov (United States)

    Huang, Yuan-Li; Tien, Hsi-Wen; Ma, Chen-Chi M.; Teng, Chih-Chun; Yu, Yi-Hsiuan; Yang, Shin-Yi; Wei, Ming-Hsiung; Wu, Sheng-Yen

    2011-10-01

    In this study, we fabricated optically transparent and electrically conductive multi-walled carbon nanotube (MWCNT) thin films using a spray-coating technique. The transparency and the electrical resistance of thin film are dependent on the nanotube content deposited on the polyethylene terephthalate (PET) substrate. Poly(acrylic acid) (PAA) and poly(N-vinyl pyrrolidone) (PVP) were used as adhesion promoters to improve MWCNT coating more significantly. The cross-linked polymer resulted in a superior bond between the MWCNTs and the substrates. The surface electrical resistance was significantly lower than the original sheet after nitric acid (HNO 3) treatment because of the removed surfactant and the increased interconnecting networks of MWCNT bundles, thus improving the electrical and optical properties of the films. Stronger interaction between the MWCNTs and the substrates resulted in lower decomposition of the polymer chain and less amounts of MWCNTs separated into the HNO 3 solution. The lower sheet electrical resistance of PVP/PAA-g-MWCNT conductive films on the PET substrate was because of a more complete conductive path with the cross-linked polymer than that without. Such an improved sheet of electrical resistance varied from 8.83 × 10 4 Ω/□ to 2.65 × 10 3 Ω/□ with 5.0 wt.% PVP/PAA-g-MWCNT sprayed on the PET after acid treatment.

  19. The generation and re-generation of social capital and enterprises in multi-stakeholders social cooperative enterprises: a system dynamic approach

    Directory of Open Access Journals (Sweden)

    Claudio Travaglini

    2012-09-01

    Full Text Available Theories on social capital and on social entrepreneurship have mainly highlighted the attitude of social capital to generate enterprises and to foster good relations between third sector organizations and the public sector. This paper considers the social capital in a specific third sector enterprise; here, multi-stakeholder social cooperatives are seen, at the same time, as social capital results, creators and incubators. In the particular enterprises that identify themselves as community social enterprises, social capital, both as organizational and relational capital, is fundamental: SCEs arise from but also produce and disseminate social capital. This paper aims to improve the building of relational social capital and the refining of helpful relations drawn from other arenas, where they were created and from where they are sometimes transferred to other realities, where their role is carried on further (often working in non-profit, horizontally and vertically arranged groups, where they share resources and relations. To represent this perspective, we use a qualitative system dynamic approach in which social capital is measured using proxies. Cooperation of volunteers, customers, community leaders and third sector local organizations is fundamental to establish trust relations between public local authorities and cooperatives. These relations help the latter to maintain long-term contracts with local authorities as providers of social services and enable them to add innovation to their services, by developing experiences and management models and maintaining an interchange with civil servants regarding these matters. The long-term relations and the organizational relations linking SCEs and public organizations help to create and to renovate social capital. Thus, multi-stakeholder cooperatives originated via social capital developed in third sector organizations produce new social capital within the cooperatives themselves and between

  20. Multi-jet correlations and colour coherence phenomena

    Directory of Open Access Journals (Sweden)

    Lee Jason S.H.

    2017-01-01

    Full Text Available In multi-jet events, colour coherence was shown to play a important role in the topology of these events. In modern Monte Carlo generators, the colour coherence effect has become an inherent feature, such that the colour coherence effect can no longer be disentangled in a simple manner. This study looks at the multi-jet correlations by comparing Monte Carlo generators in Parton Shower dominant and Matrix Element dominant regions.

  1. 3D printing nano conductive multi-walled carbon nanotube scaffolds for nerve regeneration

    Science.gov (United States)

    Lee, Se-Jun; Zhu, Wei; Nowicki, Margaret; Lee, Grace; Nyoung Heo, Dong; Kim, Junghoon; Zuo, Yi Y.; Zhang, Lijie Grace

    2018-02-01

    Objective. Nanomaterials, such as carbon nanotubes (CNTs), have been introduced to modify the surface properties of scaffolds, thus enhancing the interaction between the neural cells and biomaterials. In addition to superior electrical conductivity, CNTs can provide nanoscale structures similar to those present in the natural neural environment. The primary objective of this study is to investigate the proliferative capability and differential potential of neural stem cells (NSCs) seeded on a CNT incorporated scaffold. Approach. Amine functionalized multi-walled carbon nanotubes (MWCNTs) were incorporated with a PEGDA polymer to provide enhanced electrical properties as well as nanofeatures on the surface of the scaffold. A stereolithography 3D printer was employed to fabricate a well-dispersed MWCNT-hydrogel composite neural scaffold with a tunable porous structure. 3D printing allows easy fabrication of complex 3D scaffolds with extremely intricate microarchitectures and controlled porosity. Main results. Our results showed that MWCNT-incorporated scaffolds promoted neural stem cell proliferation and early neuronal differentiation when compared to those scaffolds without the MWCNTs. Furthermore, biphasic pulse stimulation with 500 µA current promoted neuronal maturity quantified through protein expression analysis by quantitative polymerase chain reaction. Significance. Results of this study demonstrated that an electroconductive MWCNT scaffold, coupled with electrical stimulation, may have a synergistic effect on promoting neurite outgrowth for therapeutic application in nerve regeneration.

  2. Modeling and simulation of defects detection in conductive multi-layered pieces by the eddy current technique

    International Nuclear Information System (INIS)

    Bennoud, S; Zergoug, M

    2015-01-01

    It has been shown that the eddy current method is one of the most effective techniques for the detection and characterization of surface and near-surface defects in conductive mediums especially in aluminum alloy. It is one of the most applied methods in industries which require a maximum of reliability and security (aerospace, aeronautics, nuclear, Etc). In this study, a code to solve electromagnetic problems by employing the finite element method is developed. The suggested model can simulate the probe response to the presence of a defect hidden in a multi-layered structure or a riveted structure on aluminum alloy. The developed code is based on the discretization in three dimensions of the Maxwell's equations in harmonic mode by the finite element method based on the combined potential formulations. That will enable us to interpret the results, to present them in graphical form and to carry out simulations for various applications

  3. Investigations of Orchestra Auralizations Using the Multi-Channel Multi-Source Auralization Technique

    DEFF Research Database (Denmark)

    Vigeant, Michelle; Wang, Lily M.; Rindel, Jens Holger

    2008-01-01

    a multi-channel multi-source auralization technique, involving individual five-channel anechoic recordings of each instrumental part of two symphonies. In the first study, these auralizations were subjectively compared to orchestra auralizations made using (a) a single omni-directional source, (b......) a surface source, and (c) single-channel multi-source method. Results show that the multi-source auralizations were rated to be more realistic than the surface source ones and to have larger source width than the single omni-directional source auralizations. No significant differences were found between......Room acoustics computer modeling is a tool for generating impulse responses and auralizations from modeled spaces. The auralizations are commonly made from a single-channel anechoic recording of solo instruments. For this investigation, auralizations of an entire orchestra were created using...

  4. Optimization of Multiple Related Negotiation through Multi-Negotiation Network

    Science.gov (United States)

    Ren, Fenghui; Zhang, Minjie; Miao, Chunyan; Shen, Zhiqi

    In this paper, a Multi-Negotiation Network (MNN) and a Multi- Negotiation Influence Diagram (MNID) are proposed to optimally handle Multiple Related Negotiations (MRN) in a multi-agent system. Most popular, state-of-the-art approaches perform MRN sequentially. However, a sequential procedure may not optimally execute MRN in terms of maximizing the global outcome, and may even lead to unnecessary losses in some situations. The motivation of this research is to use a MNN to handle MRN concurrently so as to maximize the expected utility of MRN. Firstly, both the joint success rate and the joint utility by considering all related negotiations are dynamically calculated based on a MNN. Secondly, by employing a MNID, an agent's possible decision on each related negotiation is reflected by the value of expected utility. Lastly, through comparing expected utilities between all possible policies to conduct MRN, an optimal policy is generated to optimize the global outcome of MRN. The experimental results indicate that the proposed approach can improve the global outcome of MRN in a successful end scenario, and avoid unnecessary losses in an unsuccessful end scenario.

  5. Generation of equivalent forms of operational trans-conductance amplifier-RC sinusoidal oscillators: the nullor approach

    Directory of Open Access Journals (Sweden)

    Raj Senani

    2014-06-01

    Full Text Available It has been shown in two earlier papers published from this study that corresponding to a given single-operational trans-conductance amplifier (single-OTA-RC and dual-OTA-RC sinusoidal oscillators, there are three other structurally distinct equivalent forms having the same characteristic equation, one of which employs both grounded capacitors (GC. In this study, an earlier nullor-based theory of generating equivalent op-amp oscillator circuits, proposed by the first author, is extended to derive equivalent OTA-RC circuits which discloses the existence of an additional number of equivalent forms for the same given OTA-RC oscillators than those predicted by the quoted earlier works, and thereby considerably enlarging the set of equivalents of a given OTA-RC oscillator. Furthermore, the presented nullor-based theory of generating equivalent OTA-RC oscillators results in three additional interesting outcomes: (i the revelation that corresponding to any given OTA-RC oscillator there are two ‘both-GC’ oscillators (and not merely one, as derived in the quoted earlier works; (ii the availability of explicit current outputs in several of the derived equivalents and (iii the realisability explicit-current-output ‘quadrature oscillators’ in some of the generated equivalent oscillators. The workability of the generated equivalent OTA-RC oscillators has been verified by SPICE simulations, based on CMOS OTAs using 0.18 µm CMOS technology process parameters, and some sample results are given.

  6. [Virtual bronchoscopy in the child using multi-slice CT: initial clinical experiences].

    Science.gov (United States)

    Kirchner, J; Laufer, U; Jendreck, M; Kickuth, R; Schilling, E M; Liermann, D

    2000-01-01

    Virtual bronchoscopy of the pediatric patient has been reported to be more difficult because of artifacts due to breathing or motion. We demonstrate the benefit of the accelerated examination based on multislice spiral CT (MSCT) in the pediatric patient which has not been reported so far. MSCT (tube voltage 120 kV, tube current 110 mA, 4 x 1 mm Slice thickness, 500 ms rotation time, Pitch 6) was performed on a CT scanner of the latest generation (Volume Zoom, Siemens Corp. Forchheim, Germany). In totally we examined 11 patients (median age 48 months, range 2-122 months) suspected of having tracheoesophageal fistula (n = 2), tracheobronchial narrowing (n = 8) due to intrinsic or extrinsic factors or injury of the bronchial system (n = 1). In all patients we obtained sufficient data for 3D reconstruction avoiding general anesthesia. 6/11 examinations were described to be without pathological finding. A definite diagnosis was obtained in 10 patients. Virtual bronchoscopy could avoid other invasive diagnostic examination in 8/11 patients (73%). Helical CT provides 3D-reconstruction and virtual bronchoscopy in the newborn as well as the infant. It avoids additional diagnostic bronchoscopy in a high percentage of all cases.

  7. Radial electromagnetic force calculation of induction motor based on multi-loop theory

    Directory of Open Access Journals (Sweden)

    HE Haibo

    2017-12-01

    Full Text Available [Objectives] In order to study the vibration and noise of induction motors, a method of radial electromagnetic force calculation is established on the basis of the multi-loop model.[Methods] Based on the method of calculating air-gap magneto motive force according to stator and rotor fundamental wave current, the analytic formulas are deduced for calculating the air-gap magneto motive force and radial electromagnetic force generated in accordance with any stator winding and rotor conducting bar current. The multi-loop theory and calculation method for the electromagnetic parameters of a motor are introduced, and a dynamic simulation model of an induction motor built to achieve the current of the stator winding and rotor conducting bars, and obtain the calculation formula of radial electromagnetic force. The radial electromagnetic force and vibration are then estimated.[Results] The experimental results indicate that the vibration acceleration frequency and amplitude of the motor are consistent with the experimental results.[Conclusions] The results and calculation method can support the low noise design of converters.

  8. Native Cellulose Microfiber-Based Hybrid Piezoelectric Generator for Mechanical Energy Harvesting Utility.

    Science.gov (United States)

    Alam, Md Mehebub; Mandal, Dipankar

    2016-01-27

    A flexible hybrid piezoelectric generator (HPG) based on native cellulose microfiber (NCMF) and polydimethylsiloxane (PDMS) with multi wall carbon nanotubes (MWCNTs) as conducting filler is presented where the further chemical treatment of the cellulose and traditional electrical poling steps for piezoelectric voltage generation is avoided. It delivers a high electrical throughput that is an open circuit voltage of ∼30 V and power density ∼9.0 μW/cm(3) under repeated hand punching. We demonstrate to power up various portable electronic units by HPG. Because cellulose is a biocompatible material, suggesting that HPG may have greater potential in biomedical applications such as implantable power source in human body.

  9. The use of multi criteria analysis to compare the operating scenarios of the hybrid generation system of wind turbines, photovoltaic modules and a fuel cell

    Science.gov (United States)

    Ceran, Bartosz

    2017-11-01

    The paper presents the results of the use of multi-criteria analysis to compare hybrid power generation system collaboration scenarios (HSW) consisting of wind turbines, solar panels and energy storage electrolyzer - PEM type fuel cell with electricity system. The following scenarios were examined: the base S-I-hybrid system powers the off-grid mode receiver, S-II, S-III, S-IV scenarios-electricity system covers 25%, 50%, 75% of energy demand by the recipient. The effect of weights of the above-mentioned criteria on the final result of the multi-criteria analysis was examined.

  10. Multi-Band Multi-Tone Tunable Millimeter-Wave Frequency Synthesizer For Satellite Beacon Transmitter

    Science.gov (United States)

    Simons, Rainee N.; Wintucky, Edwin G.

    2016-01-01

    This paper presents the design and test results of a multi-band multi-tone tunable millimeter-wave frequency synthesizer, based on a solid-state frequency comb generator. The intended application of the synthesizer is in a satellite beacon transmitter for radio wave propagation studies at K-band (18 to 26.5 GHz), Q-band (37 to 42 GHz), and E-band (71 to 76 GHz). In addition, the architecture for a compact beacon transmitter, which includes the multi-tone synthesizer, polarizer, horn antenna, and power/control electronics, has been investigated for a notional space-to-ground radio wave propagation experiment payload on a small satellite. The above studies would enable the design of robust high throughput multi-Gbps data rate future space-to-ground satellite communication links.

  11. Multi-objective optimization design of air distribution of grate cooler by entropy generation minimization and genetic algorithm

    International Nuclear Information System (INIS)

    Shao, Wei; Cui, Zheng; Cheng, Lin

    2016-01-01

    Highlights: • A multi-objective optimization model of air distribution of grate cooler by genetic algorithm is proposed. • Pareto Front is obtained and validated by comparing with operating data. • Optimal schemes are compared and selected by engineering background. • Total power consumption after optimization decreases 61.10%. • Thickness of clinker on three grate plates is thinner. - Abstract: The cooling air distributions of grate cooler exercise a great influence on the clinker cooling efficiency and power consumption of cooling fans. A multi-objective optimization model of air distributions of grate cooler with cross-flow heat exchanger analogy is proposed in this paper. Firstly, thermodynamic and flow models of clinker cooling process is carried out. Then based on entropy generation minimization analysis, modified entropy generation numbers caused by heat transfer and pressure drop are chosen as objective functions respectively which optimized by genetic algorithm. The design variables are superficial velocities of air chambers and thicknesses of clinker layers on different grate plates. A set of Pareto optimal solutions which two objectives are optimized simultaneously is achieved. Scattered distributions of design variables resulting in the conflict between two objectives are brought out. The final optimal air distribution and thicknesses of clinker layers are selected from the Pareto optimal solutions based on power consumption of cooling fans minimization and validated by measurements. Compared with actual operating scheme, the total air volumes of optimized schemes decrease 2.4%, total power consumption of cooling fans decreases 61.1% and the outlet temperature of clinker decreases 122.9 °C which shows a remarkable energy-saving effect on energy consumption.

  12. Multi-step capacitor discharges as an RF generator

    International Nuclear Information System (INIS)

    Hotta, Eiki; Yamamoto, Shunji; Ishii, Shozo; Hayashi, Izumi

    1979-01-01

    A variety of methods have been developed for large output radio frequency (RF) generators to heat and stabilize high temperature plasma. As the generators for this purpose, capacitor discharge, cable discharge, and oscillation with electronic tubes are considered. Here, a new RF generator is reported, which utilizes capacitor discharge to extract heavy current, and solves the difficulty of short duration by employing multistep discharges. The authors solved the problem of frequency decrease in capacitor discharge by cutting off the unnecessary capacitors reasonably from the load circuit, using the additional circuit for shunting current and vacuum gap switches. The vacuum gap switches and the trigger system are described together with the RF generator manufactured. The generator was fabricated to be rather compact for its large output and simple in circuitry as compared with conventional oscillator systems. The shortcomings are frequency variation and the improper phase of switching the next step in to cause instability, when the load change occurs. It would be difficult to operate the generator in a RF range of more than about 10 MHz due to jitter of the vacuum gap switches and others. (Wakatsuki, Y.)

  13. Multi-wavelength fiber laser in the S-band region using a Sagnac loop mirror as a comb generator in an SOA gain medium

    International Nuclear Information System (INIS)

    Zulkifli, M Z; Hassan, N A; Awang, N A; Ahmad, H; Ghani, Z A; Harun, S W

    2010-01-01

    A simple design of multi-wavelength generation in the S-band region of the optical network transmission is proposed. The design consists of broad-band fiber Bragg grating (BB-FBG), which acts as a filter to enhance operation in the S-band region. A Sagnac loop mirror (SLM) is used to generate multiple wavelength oscillations in the ring cavity. The output consists of 60 lasing wavelengths oscillating simultaneously between 1464 nm and 1521 nm with a spacing of 0.92 nm and an output linewidth of 0.66 nm

  14. Multi-objective decision-making model based on CBM for an aircraft fleet

    Science.gov (United States)

    Luo, Bin; Lin, Lin

    2018-04-01

    Modern production management patterns, in which multi-unit (e.g., a fleet of aircrafts) are managed in a holistic manner, have brought new challenges for multi-unit maintenance decision making. To schedule a good maintenance plan, not only does the individual machine maintenance have to be considered, but also the maintenance of the other individuals have to be taken into account. Since most condition-based maintenance researches for aircraft focused on solely reducing maintenance cost or maximizing the availability of single aircraft, as well as considering that seldom researches concentrated on both the two objectives: minimizing cost and maximizing the availability of a fleet (total number of available aircraft in fleet), a multi-objective decision-making model based on condition-based maintenance concentrated both on the above two objectives is established. Furthermore, in consideration of the decision maker may prefer providing the final optimal result in the form of discrete intervals instead of a set of points (non-dominated solutions) in real decision-making problem, a novel multi-objective optimization method based on support vector regression is proposed to solve the above multi-objective decision-making model. Finally, a case study regarding a fleet is conducted, with the results proving that the approach efficiently generates outcomes that meet the schedule requirements.

  15. A cellular automata simulation study of surface roughening resulting from multi-atom etch pit generation during sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Toh, Y S; Nobes, M J; Carter, G [Dept. of Electronic and Electrical Engineering, Univ. of Salford (United Kingdom)

    1992-04-01

    A two-dimensional square matrix of pseudo-atomic positions is erected and atom removal from the ''surface'' is effected randomly. Either single atoms or groups of atoms (to simulate multi-atom pit generation) are removed. The characteristics of the evolving roughened, terraced ''surface'' are evaluated as a function of the total number of atoms, or equivalent numbers of atomic layers, removed. These characteristics include the ''mean'' position of the sputtered surface, the standard deviation of terrace length about the mean and the form of the terrace length distributions. The results of the single-atom removal mode compare exactly with theoretical predictions in that, for large numbers of atoms removed the depth position of the mean of the terrace length distribution is identical to the mean sputtered depth and the standard deviation increases as the square root of this depth. For multi-atom removal modes (which cannot be predicted theoretically) the standard deviation also increases as the square root of the mean sputtered depth but with a larger proportionality constant. The implications of these observations for the evolution of surface morphology during high yield sputtering is discussed. (orig.).

  16. Dynamic configuration management of a multi-standard and multi-mode reconfigurable multi-ASIP architecture for turbo decoding

    Science.gov (United States)

    Lapotre, Vianney; Gogniat, Guy; Baghdadi, Amer; Diguet, Jean-Philippe

    2017-12-01

    The multiplication of connected devices goes along with a large variety of applications and traffic types needing diverse requirements. Accompanying this connectivity evolution, the last years have seen considerable evolutions of wireless communication standards in the domain of mobile telephone networks, local/wide wireless area networks, and Digital Video Broadcasting (DVB). In this context, intensive research has been conducted to provide flexible turbo decoder targeting high throughput, multi-mode, multi-standard, and power consumption efficiency. However, flexible turbo decoder implementations have not often considered dynamic reconfiguration issues in this context that requires high speed configuration switching. Starting from this assessment, this paper proposes the first solution that allows frame-by-frame run-time configuration management of a multi-processor turbo decoder without compromising the decoding performances.

  17. Real-time scene and signature generation for ladar and imaging sensors

    Science.gov (United States)

    Swierkowski, Leszek; Christie, Chad L.; Antanovskii, Leonid; Gouthas, Efthimios

    2014-05-01

    This paper describes development of two key functionalities within the VIRSuite scene simulation program, broadening its scene generation capabilities and increasing accuracy of thermal signatures. Firstly, a new LADAR scene generation module has been designed. It is capable of simulating range imagery for Geiger mode LADAR, in addition to the already existing functionality for linear mode systems. Furthermore, a new 3D heat diffusion solver has been developed within the VIRSuite signature prediction module. It is capable of calculating the temperature distribution in complex three-dimensional objects for enhanced dynamic prediction of thermal signatures. With these enhancements, VIRSuite is now a robust tool for conducting dynamic simulation for missiles with multi-mode seekers.

  18. Report on achievements in fiscal 1998. Development of technologies to put photovoltaic power generation systems into practical use - Demonstrative research on photovoltaic power generation system (Research on multi-hybrid photovoltaic power generation system); 1998 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Taiyoko hatsuden system no jissho kenkyu (taiyoko hatsuden multi hybrid system no kenkyu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    A multi-hybrid system integrating photovoltaic and wind power generation systems with the existing diesel engine power generation system was assumed for installation in power systems in islands. System analyzing simulation and economic performance analyses were performed to consider system configurations suitable for islands from the viewpoints of system stability and economic performance. The work was progressed by dividing the subject into (1) research on the system configurations, and (2) studies on the economic performance. In performing either work, the power demand was classified as large (in Miyako Island), medium (in Kume Island) and small (in Tarama Island), and the introduction years into 1997, 2000, and 2005. In Item (1), the system parameter specifications were put into order, and the system analyzing simulation was performed, wherein it was verified that the system will be stabilized by introducing a system stabilizing equipment (batteries and an inverter) and by limiting the output from the wind power generation. In Item (2), it was made clear that the power generation cost is equivalent to or lower than the present cost, making reduction in fuel consumption possible. It was also disclosed that the introduction is most effective in small islands, and drop in the power generation amount due to limiting the output from the wind power generation is small. (NEDO)

  19. Internalisation of external cost in the power generation sector: Analysis with Global Multi-regional MARKAL model

    International Nuclear Information System (INIS)

    Rafaj, Peter; Kypreos, Socrates

    2007-01-01

    The Global MARKAL-Model (GMM), a multi-regional 'bottom-up' partial equilibrium model of the global energy system with endogenous technological learning, is used to address impacts of internalisation of external costs from power production. This modelling approach imposes additional charges on electricity generation, which reflect the costs of environmental and health damages from local pollutants (SO 2 , NO x ) and climate change, wastes, occupational health, risk of accidents, noise and other burdens. Technologies allowing abatement of pollutants emitted from power plants are rapidly introduced into the energy system, for example, desulphurisation, NO x removal, and CO 2 scrubbers. The modelling results indicate substantial changes in the electricity production system in favour of natural gas combined cycle, nuclear power and renewables induced by internalisation of external costs and also efficiency loss due to the use of scrubbers. Structural changes and fuel switching in the electricity sector result in significant reduction of emissions of both local pollution and CO 2 over the modelled time period. Strong decarbonisation impact of internalising local externalities suggests that ancillary benefits can be expected from policies directly addressing other issues then CO 2 mitigation. Finally, the detailed analysis of the total generation cost of different technologies points out that inclusion of external cost in the price of electricity increases competitiveness of non-fossil generation sources and fossil power plants with emission control

  20. Active and Reactive Power Control Strategy for Grid-Connected Six-Phase Generator by Using Multi-Modular Matrix Converters

    Directory of Open Access Journals (Sweden)

    David Caballero

    2016-12-01

    Full Text Available This paper proposes an active and reactive power control strategy based on predictive control approaches applied to gridconnected renewable energy systems. To accomplish this a multi-modular matrix converter topologies are used in combination with a simple but efficient grid synchronization strategy. The theoretical performance analysis is performed considering a six-phase wind energy generator system interconnected with the grid. Results based on a MATLAB/Simulink simulation environment are discussed and the most relevant characteristics of the proposed control technique are highlighted considering the total harmonic distortion and the mean squared error as a parameters of performance.

  1. Co-Labeling for Multi-View Weakly Labeled Learning.

    Science.gov (United States)

    Xu, Xinxing; Li, Wen; Xu, Dong; Tsang, Ivor W

    2016-06-01

    It is often expensive and time consuming to collect labeled training samples in many real-world applications. To reduce human effort on annotating training samples, many machine learning techniques (e.g., semi-supervised learning (SSL), multi-instance learning (MIL), etc.) have been studied to exploit weakly labeled training samples. Meanwhile, when the training data is represented with multiple types of features, many multi-view learning methods have shown that classifiers trained on different views can help each other to better utilize the unlabeled training samples for the SSL task. In this paper, we study a new learning problem called multi-view weakly labeled learning, in which we aim to develop a unified approach to learn robust classifiers by effectively utilizing different types of weakly labeled multi-view data from a broad range of tasks including SSL, MIL and relative outlier detection (ROD). We propose an effective approach called co-labeling to solve the multi-view weakly labeled learning problem. Specifically, we model the learning problem on each view as a weakly labeled learning problem, which aims to learn an optimal classifier from a set of pseudo-label vectors generated by using the classifiers trained from other views. Unlike traditional co-training approaches using a single pseudo-label vector for training each classifier, our co-labeling approach explores different strategies to utilize the predictions from different views, biases and iterations for generating the pseudo-label vectors, making our approach more robust for real-world applications. Moreover, to further improve the weakly labeled learning on each view, we also exploit the inherent group structure in the pseudo-label vectors generated from different strategies, which leads to a new multi-layer multiple kernel learning problem. Promising results for text-based image retrieval on the NUS-WIDE dataset as well as news classification and text categorization on several real-world multi

  2. Connectivity ranking of heterogeneous random conductivity models

    Science.gov (United States)

    Rizzo, C. B.; de Barros, F.

    2017-12-01

    To overcome the challenges associated with hydrogeological data scarcity, the hydraulic conductivity (K) field is often represented by a spatial random process. The state-of-the-art provides several methods to generate 2D or 3D random K-fields, such as the classic multi-Gaussian fields or non-Gaussian fields, training image-based fields and object-based fields. We provide a systematic comparison of these models based on their connectivity. We use the minimum hydraulic resistance as a connectivity measure, which it has been found to be strictly correlated with early time arrival of dissolved contaminants. A computationally efficient graph-based algorithm is employed, allowing a stochastic treatment of the minimum hydraulic resistance through a Monte-Carlo approach and therefore enabling the computation of its uncertainty. The results show the impact of geostatistical parameters on the connectivity for each group of random fields, being able to rank the fields according to their minimum hydraulic resistance.

  3. Characterization of respiratory drug delivery with enhanced condensational growth using an individual path model of the entire tracheobronchial airways.

    Science.gov (United States)

    Tian, Geng; Longest, Philip Worth; Su, Guoguang; Hindle, Michael

    2011-03-01

    The objective of this study was to evaluate the delivery of inhaled pharmaceutical aerosols using an enhanced condensational growth (ECG) approach in an airway model extending from the oral cavity to the end of the tracheobronchial (TB) region. The geometry consisted of an elliptical mouth-throat (MT) model, the upper TB airways extending to bifurcation B3, and a subsequent individual path model entering the right lower lobe of the lung. Submicrometer monodisperse aerosols with diameters of 560 and 900 nm were delivered to the mouth inlet under control (25 °C with subsaturated air) or ECG (39 or 42 °C with saturated air) conditions. Flow fields and droplet characteristics were simulated using a computational fluid dynamics model that was previously demonstrated to accurately predict aerosol size growth and deposition. Results indicated that both the control and ECG delivery cases produced very little deposition in the MT and upper TB model (approximately 1%). Under ECG delivery conditions, large size increases of the aerosol droplets were observed resulting in mass median aerodynamic diameters of 2.4-3.3 μm exiting B5. This increase in aerosol size produced an order of magnitude increase in aerosol deposition within the TB airways compared with the controls, with TB deposition efficiencies of approximately 32-46% for ECG conditions. Estimates of downstream pulmonary deposition indicted near full lung retention of the aerosol during ECG delivery. Furthermore, targeting the region of TB deposition by controlling the inlet temperature conditions and initial aerosol size also appeared possible.

  4. Primary adenoid cystic carcinoma of the tracheobronchial tree: A decade-long experience at a health centre in Mexico

    Directory of Open Access Journals (Sweden)

    Arturo Cortés-Télles

    2012-01-01

    Full Text Available Background : Mexico′s National Institute of Respiratory Diseases (NIRD is a third-level national reference center. Primary adenoid cystic carcinoma (PACC is an uncommon neoplastic disorder; hence improvements in the description of this disease are needed. Materials and Methods: This is a retrospective clinical study based on all consecutive patients with pathological diagnoses of PACC seen at the NIRD between January 1, 2000 and December 31, 2009. Results: We identified 9 cases of PACC (67% female out of a total of 2,634 patients with lung cancer seen during the period analyzed. The mean age of those 9 patients was 41 years (IQR 36-57, and the frequency of PACC at our center was 0.3%. It is important to note that 67% of those patients had a history of smoking and that 6 of the 9 had the antecedent of previous exposure to biomass fuel smoke. Baseline arterial blood gas analyses revealed a median of 61 mmHg for pO 2 and 28.5 mmHg for pCO 2 . Median FVC was 78%, while FEV 1 was 77% with an FEV 1 /FVC ratio of 78. Death occurred in 56% of cases, and the median survival time was 17 months (IQR 6-26 after the initial diagnosis. Conclusions: The frequency of tracheobronchial PACC among patients with lung cancer was similar to that previously reported (0.3%. According to our results, lung function has no specific phenotype in this disease; however, some abnormalities could be related to potential risk factors such as tobacco use and exposure to biomass fuel smoke.

  5. A Single Rod Multi-modality Multi-interface Level Sensor Using an AC Current Source

    Directory of Open Access Journals (Sweden)

    Abdulgader Hwili

    2008-05-01

    Full Text Available Crude oil separation is an important process in the oil industry. To make efficient use of the separators, it is important to know their internal behaviour, and to measure the levels of multi-interfaces between different materials, such as gas-foam, foam-oil, oil-emulsion, emulsion-water and water-solids. A single-rod multi-modality multi-interface level sensor is presented, which has a current source, and electromagnetic modalities. Some key issues have been addressed, including the effect of salt content and temperature i.e. conductivity on the measurement.

  6. A multi-objective optimization problem for multi-state series-parallel systems: A two-stage flow-shop manufacturing system

    International Nuclear Information System (INIS)

    Azadeh, A.; Maleki Shoja, B.; Ghanei, S.; Sheikhalishahi, M.

    2015-01-01

    This research investigates a redundancy-scheduling optimization problem for a multi-state series parallel system. The system is a flow shop manufacturing system with multi-state machines. Each manufacturing machine may have different performance rates including perfect performance, decreased performance and complete failure. Moreover, warm standby redundancy is considered for the redundancy allocation problem. Three objectives are considered for the problem: (1) minimizing system purchasing cost, (2) minimizing makespan, and (3) maximizing system reliability. Universal generating function is employed to evaluate system performance and overall reliability of the system. Since the problem is in the NP-hard class of combinatorial problems, genetic algorithm (GA) is used to find optimal/near optimal solutions. Different test problems are generated to evaluate the effectiveness and efficiency of proposed approach and compared to simulated annealing optimization method. The results show the proposed approach is capable of finding optimal/near optimal solution within a very reasonable time. - Highlights: • A redundancy-scheduling optimization problem for a multi-state series parallel system. • A flow shop with multi-state machines and warm standby redundancy. • Objectives are to optimize system purchasing cost, makespan and reliability. • Different test problems are generated and evaluated by a unique genetic algorithm. • It locates optimal/near optimal solution within a very reasonable time

  7. Fast and fuzzy multi-objective radiotherapy treatment plan generation for head and neck cancer patients with the lexicographic reference point method (LRPM)

    Science.gov (United States)

    van Haveren, Rens; Ogryczak, Włodzimierz; Verduijn, Gerda M.; Keijzer, Marleen; Heijmen, Ben J. M.; Breedveld, Sebastiaan

    2017-06-01

    Previously, we have proposed Erasmus-iCycle, an algorithm for fully automated IMRT plan generation based on prioritised (lexicographic) multi-objective optimisation with the 2-phase ɛ-constraint (2pɛc) method. For each patient, the output of Erasmus-iCycle is a clinically favourable, Pareto optimal plan. The 2pɛc method uses a list of objective functions that are consecutively optimised, following a strict, user-defined prioritisation. The novel lexicographic reference point method (LRPM) is capable of solving multi-objective problems in a single optimisation, using a fuzzy prioritisation of the objectives. Trade-offs are made globally, aiming for large favourable gains for lower prioritised objectives at the cost of only slight degradations for higher prioritised objectives, or vice versa. In this study, the LRPM is validated for 15 head and neck cancer patients receiving bilateral neck irradiation. The generated plans using the LRPM are compared with the plans resulting from the 2pɛc method. Both methods were capable of automatically generating clinically relevant treatment plans for all patients. For some patients, the LRPM allowed large favourable gains in some treatment plan objectives at the cost of only small degradations for the others. Moreover, because of the applied single optimisation instead of multiple optimisations, the LRPM reduced the average computation time from 209.2 to 9.5 min, a speed-up factor of 22 relative to the 2pɛc method.

  8. A novel intravital multi-harmonic generation microscope for early diagnosis of oral cancer

    Science.gov (United States)

    Cheng, Yu-Hsiang; Lin, Chih-Feng; Shih, Ting-Fang; Sun, Chi-Kuang

    2013-03-01

    Oral cancer is one of the most frequently diagnosed human cancers and leading causes of cancer death all over the world, but the prognosis and overall survival rate are still poor because of delay in diagnosis and lack of early intervention. The failure of early diagnosis is due to insufficiency of proper diagnostic and screening tools and most patients are reluctant to undergo biopsy. Optical virtual biopsy techniques, for imaging cells and tissues at microscopic details capable of differentiating benign from malignant lesions non-invasively, are thus highly desirable. A novel multi-harmonic generation microscope, excited by a 1260 nm Cr:forsterite laser, with second and third harmonic signals demonstrating collagen fiber distribution and cell morphology in a sub-micron resolution, was developed for clinical use. To achieve invivo observation inside the human oral cavity, a small objective probe with a suction capability was carefully designed for patients' comfort and stability. By remotely changing its focus point, the same objective can image the mucosa surface with a low magnification, illuminated by side light-emitting diodes, with a charge-coupled device (CCD) for site location selection before the harmonic generation biopsy was applied. Furthermore, the slow galvanometer mirror and the fast resonant mirror provide a 30 fps frame rate for high-speed real-time observation and the z-motor of this system is triggered at the same rate to provide fast 3D scanning, again ensuring patients' comfort. Focusing on the special cytological and morphological changes of the oral epithelial cells, our preliminary result disclosed excellent consistency with traditional histopathology studies.

  9. Prospects of conducting polymers in biosensors

    International Nuclear Information System (INIS)

    Malhotra, Bansi D.; Chaubey, Asha; Singh, S.P.

    2006-01-01

    Applications of conducting polymers to biosensors have recently aroused much interest. This is because these molecular electronic materials offer control of different parameters such as polymer layer thickness, electrical properties and bio-reagent loading, etc. Moreover, conducting polymer based biosensors are likely to cater to the pressing requirements such as biocompatibility, possibility of in vivo sensing, continuous monitoring of drugs or metabolites, multi-parametric assays, miniaturization and high information density. This paper deals with the emerging trends in conducting polymer based biosensors during the last about 5 years

  10. The CLIC Study of a Multi-TeV $e^\\pm$ Linear Collider

    CERN Document Server

    Bossart, Rudolf; Carron, G; Coosemans, Williame; Corsini, R; D'Amico, T E; Delahaye, J P; Godot, J C; Guignard, Gilbert; Hagel, J; Hutchins, S; Jensen, E; Luong, M; Millich, Antonio; Pearce, P; Potier, J P; Riche, A J; Rinolfi, Louis; Schulte, Daniel; Suberlucq, Guy; Thorndahl, L; Valentini, M; Wilson, Ian H; Wuensch, Walter; Napoly, O; Raubenheimer, T O; Ruth, Ronald D; Syratchev, I V

    1999-01-01

    The progress of the Compact LInear Collider (CLIC) study of a multi-TeV (0.5 - 5 TeV) high-luminosity (5'1033 to 1.5'1035 cm-2 sec-1) e± linear collider based on Two-Beam Acceleration (TBA) is presented. The length and, in consequence, the cost of the overall complex is reduced by the use of high accelerating fields (150 MV/m), which are generated by specially damped 30 GHz normal-conducting accelerating structures. The large amount of RF power (400 MW/m) required to generate these high fields is provided by a novel RF power generating scheme which is potentially both cost and power efficient. After summarising the progress made in the developments of 30 GHz components and the performance obtained in the present phase of the CLIC Test Facility (CTF2), the design of a new test facility (CTF3), which will demonstrate the feasibility of the RF power generating scheme, is described

  11. MUSIC: MUlti-Scale Initial Conditions

    Science.gov (United States)

    Hahn, Oliver; Abel, Tom

    2013-11-01

    MUSIC generates multi-scale initial conditions with multiple levels of refinements for cosmological ‘zoom-in’ simulations. The code uses an adaptive convolution of Gaussian white noise with a real-space transfer function kernel together with an adaptive multi-grid Poisson solver to generate displacements and velocities following first- (1LPT) or second-order Lagrangian perturbation theory (2LPT). MUSIC achieves rms relative errors of the order of 10-4 for displacements and velocities in the refinement region and thus improves in terms of errors by about two orders of magnitude over previous approaches. In addition, errors are localized at coarse-fine boundaries and do not suffer from Fourier space-induced interference ringing.

  12. Multi-criteria objective based climate change impact assessment for multi-purpose multi-reservoir systems

    Science.gov (United States)

    Müller, Ruben; Schütze, Niels

    2014-05-01

    Water resources systems with reservoirs are expected to be sensitive to climate change. Assessment studies that analyze the impact of climate change on the performance of reservoirs can be divided in two groups: (1) Studies that simulate the operation under projected inflows with the current set of operational rules. Due to non adapted operational rules the future performance of these reservoirs can be underestimated and the impact overestimated. (2) Studies that optimize the operational rules for best adaption of the system to the projected conditions before the assessment of the impact. The latter allows for estimating more realistically future performance and adaption strategies based on new operation rules are available if required. Multi-purpose reservoirs serve various, often conflicting functions. If all functions cannot be served simultaneously at a maximum level, an effective compromise between multiple objectives of the reservoir operation has to be provided. Yet under climate change the historically preferenced compromise may no longer be the most suitable compromise in the future. Therefore a multi-objective based climate change impact assessment approach for multi-purpose multi-reservoir systems is proposed in the study. Projected inflows are provided in a first step using a physically based rainfall-runoff model. In a second step, a time series model is applied to generate long-term inflow time series. Finally, the long-term inflow series are used as driving variables for a simulation-based multi-objective optimization of the reservoir system in order to derive optimal operation rules. As a result, the adapted Pareto-optimal set of diverse best compromise solutions can be presented to the decision maker in order to assist him in assessing climate change adaption measures with respect to the future performance of the multi-purpose reservoir system. The approach is tested on a multi-purpose multi-reservoir system in a mountainous catchment in Germany. A

  13. Neutral- and Multi-Colored Semitransparent Perovskite Solar Cells.

    Science.gov (United States)

    Lee, Kyu-Tae; Guo, L Jay; Park, Hui Joon

    2016-04-11

    In this review, we summarize recent works on perovskite solar cells with neutral- and multi-colored semitransparency for building-integrated photovoltaics and tandem solar cells. The perovskite solar cells exploiting microstructured arrays of perovskite "islands" and transparent electrodes-the latter of which include thin metallic films, metal nanowires, carbon nanotubes, graphenes, and transparent conductive oxides for achieving optical transparency-are investigated. Moreover, the perovskite solar cells with distinctive color generation, which are enabled by engineering the band gap of the perovskite light-harvesting semiconductors with chemical management and integrating with photonic nanostructures, including microcavity, are discussed. We conclude by providing future research directions toward further performance improvements of the semitransparent perovskite solar cells.

  14. SHAPE GENERATION BY MEANS OF A NEW METHOD OF ORTHOGRAPHIC REPRESENTATION ("PROEKTIVOGRAFIYA": DRAWINGS OF MULTI-COMPONENT POLYHEDRA

    Directory of Open Access Journals (Sweden)

    Andrey Ivashchenko Viktorovich

    2012-10-01

    Full Text Available The authors analyze the capabilities of a traditional set of shape generation techniques that employ orthographic representation in the generation of polyhedra with account for the advanced approach to the research of new multi-nuclear structures. In the past, designs based on one nucleus were used in practice. The use of two or more nuclei is considered in the article. In the most common case, the resulting system of planes will constitute multiple orthographic representations. The characteristics of a binuclear system depend on the mutual positions and relation of dimensions of the nuclei. In addition to regular parameters, complete description of the system need particular supplementary parameters that determine the mutual positions of the nuclei. Increase in the number of nuclei causes increase in the number of descriptive parameters. The authors provide examples of binuclear systems composed of tetrahedrons, cubes, and dodecahedrons, implemented in the Delphi medium. The results can be exported into any three-dimensional modeling system with a view to their further study and use.

  15. Automatic Generation of Wide Dynamic Range Image without Pseudo-Edge Using Integration of Multi-Steps Exposure Images

    Science.gov (United States)

    Migiyama, Go; Sugimura, Atsuhiko; Osa, Atsushi; Miike, Hidetoshi

    Recently, digital cameras are offering technical advantages rapidly. However, the shot image is different from the sight image generated when that scenery is seen with the naked eye. There are blown-out highlights and crushed blacks in the image that photographed the scenery of wide dynamic range. The problems are hardly generated in the sight image. These are contributory cause of difference between the shot image and the sight image. Blown-out highlights and crushed blacks are caused by the difference of dynamic range between the image sensor installed in a digital camera such as CCD and CMOS and the human visual system. Dynamic range of the shot image is narrower than dynamic range of the sight image. In order to solve the problem, we propose an automatic method to decide an effective exposure range in superposition of edges. We integrate multi-step exposure images using the method. In addition, we try to erase pseudo-edges using the process to blend exposure values. Afterwards, we get a pseudo wide dynamic range image automatically.

  16. Multi-generational drinking of bottled low mineral water impairs bone quality in female rats.

    Directory of Open Access Journals (Sweden)

    Zhiqun Qiu

    Full Text Available Because of reproductions and hormone changes, females are more sensitive to bone mineral loss during their lifetime. Bottled water has become more popular in recent years, and a large number of products are low mineral water. However, research on the effects of drinking bottled low mineral water on bone health is sparse.To elucidate the skeletal effects of multi-generational bottled water drinking in female rats.Rats continuously drank tap water (TW, bottled natural water (bNW, bottled mineralized water (bMW, or bottled purified water (bPW for three generations.The maximum deflection, elastic deflection, and ultimate strain of the femoral diaphysis in the bNW, bMW, and bPW groups and the fracture strain in the bNW and bMW groups were significantly decreased. The tibiae calcium levels in both the bNW and bPW groups were significantly lower than that in the TW group. The tibiae and teeth magnesium levels in both the bNW and bPW groups were significantly lower than those in the TW group. The collagen turnover markers PICP (in both bNW and bPW groups were significantly lower than that in the TW group. In all three low mineral water groups, the 1,25-dihydroxy-vitamin D levels were significantly lower than those in the TW group.Long-term drinking of low mineral water may disturb bone metabolism and biochemical properties and therefore weaken biomechanical bone properties in females. Drinking tap water, which contains adequate minerals, was found to be better for bone health. To our knowledge, this is the first report on drinking bottled low mineral water and female bone quality on three generation model.

  17. Conduction quantization in monolayer MoS2

    Science.gov (United States)

    Li, T. S.

    2016-10-01

    We study the ballistic conduction of a monolayer MoS2 subject to a spatially modulated magnetic field by using the Landauer-Buttiker formalism. The band structure depends sensitively on the field strength, and its change has profound influence on the electron conduction. The conductance is found to demonstrate multi-step behavior due to the discrete number of conduction channels. The sharp peak and rectangular structures of the conductance are stretched out as temperature increases, due to the thermal broadening of the derivative of the Fermi-Dirac distribution function. Finally, quantum behavior in the conductance of MoS2 can be observed at temperatures below 10 K.

  18. Multi-fuel multi-product operation of IGCC power plants with carbon capture and storage (CCS)

    International Nuclear Information System (INIS)

    Cormos, Ana-Maria; Dinca, Cristian; Cormos, Calin-Cristian

    2015-01-01

    This paper investigates multi-fuel multi-product operation of IGCC plants with carbon capture and storage (CCS). The investigated plant designs co-process coal with different sorts of biomass (e.g. sawdust) and solid wastes, through gasification, leading to different decarbonised energy vectors (power, hydrogen, heat, substitute natural gas etc.) simultaneous with carbon capture. Co-gasification of coal with different renewable energy sources coupled with carbon capture will pave the way towards zero emissions power plants. The energy conversions investigated in the paper were simulated using commercial process flow modelling package (ChemCAD) in order to produce mass and energy balances necessary for the proposed evaluation. As illustrative cases, hydrogen and power co-generation and Fischer–Tropsch fuel synthesis (both with carbon capture), were presented. The case studies investigated in the paper produce a flexible ratio between power and hydrogen (in the range of 400–600 MW net electricity and 0–200 MW th hydrogen considering the lower heating value) with at least 90% carbon capture rate. Special emphasis were given to fuel selection criteria for optimisation of gasification performances (fuel blending), to the selection criteria for gasification reactor in a multi-fuel multi-product operation scenario, modelling and simulation of whole process, to thermal and power integration of processes, flexibility analysis of the energy conversion processes, in-depth techno-economic and environmental assessment etc. - Highlights: • Assessment of IGCC-based energy vectors poly-generation systems with CCS. • Optimisation of gasification performances and CO 2 emissions by fuel blending. • Multi-fuel multi-product operation of gasification plants

  19. Numerical solution to a multi-dimensional linear inverse heat conduction problem by a splitting-based conjugate gradient method

    International Nuclear Information System (INIS)

    Dinh Nho Hao; Nguyen Trung Thanh; Sahli, Hichem

    2008-01-01

    In this paper we consider a multi-dimensional inverse heat conduction problem with time-dependent coefficients in a box, which is well-known to be severely ill-posed, by a variational method. The gradient of the functional to be minimized is obtained by aids of an adjoint problem and the conjugate gradient method with a stopping rule is then applied to this ill-posed optimization problem. To enhance the stability and the accuracy of the numerical solution to the problem we apply this scheme to the discretized inverse problem rather than to the continuous one. The difficulties with large dimensions of discretized problems are overcome by a splitting method which only requires the solution of easy-to-solve one-dimensional problems. The numerical results provided by our method are very good and the techniques seem to be very promising.

  20. Multi-agent based distributed control architecture for microgrid energy management and optimization

    International Nuclear Information System (INIS)

    Basir Khan, M. Reyasudin; Jidin, Razali; Pasupuleti, Jagadeesh

    2016-01-01

    Highlights: • A new multi-agent based distributed control architecture for energy management. • Multi-agent coordination based on non-cooperative game theory. • A microgrid model comprised of renewable energy generation systems. • Performance comparison of distributed with conventional centralized control. - Abstract: Most energy management systems are based on a centralized controller that is difficult to satisfy criteria such as fault tolerance and adaptability. Therefore, a new multi-agent based distributed energy management system architecture is proposed in this paper. The distributed generation system is composed of several distributed energy resources and a group of loads. A multi-agent system based decentralized control architecture was developed in order to provide control for the complex energy management of the distributed generation system. Then, non-cooperative game theory was used for the multi-agent coordination in the system. The distributed generation system was assessed by simulation under renewable resource fluctuations, seasonal load demand and grid disturbances. The simulation results show that the implementation of the new energy management system proved to provide more robust and high performance controls than conventional centralized energy management systems.

  1. Robust Automated Image Co-Registration of Optical Multi-Sensor Time Series Data: Database Generation for Multi-Temporal Landslide Detection

    Directory of Open Access Journals (Sweden)

    Robert Behling

    2014-03-01

    Full Text Available Reliable multi-temporal landslide detection over longer periods of time requires multi-sensor time series data characterized by high internal geometric stability, as well as high relative and absolute accuracy. For this purpose, a new methodology for fully automated co-registration has been developed allowing efficient and robust spatial alignment of standard orthorectified data products originating from a multitude of optical satellite remote sensing data of varying spatial resolution. Correlation-based co-registration uses world-wide available terrain corrected Landsat Level 1T time series data as the spatial reference, ensuring global applicability. The developed approach has been applied to a multi-sensor time series of 592 remote sensing datasets covering an approximately 12,000 km2 area in Southern Kyrgyzstan (Central Asia strongly affected by landslides. The database contains images acquired during the last 26 years by Landsat (ETM, ASTER, SPOT and RapidEye sensors. Analysis of the spatial shifts obtained from co-registration has revealed sensor-specific alignments ranging between 5 m and more than 400 m. Overall accuracy assessment of these alignments has resulted in a high relative image-to-image accuracy of 17 m (RMSE and a high absolute accuracy of 23 m (RMSE for the whole co-registered database, making it suitable for multi-temporal landslide detection at a regional scale in Southern Kyrgyzstan.

  2. Multi-model analysis in hydrological prediction

    Science.gov (United States)

    Lanthier, M.; Arsenault, R.; Brissette, F.

    2017-12-01

    Hydrologic modelling, by nature, is a simplification of the real-world hydrologic system. Therefore ensemble hydrological predictions thus obtained do not present the full range of possible streamflow outcomes, thereby producing ensembles which demonstrate errors in variance such as under-dispersion. Past studies show that lumped models used in prediction mode can return satisfactory results, especially when there is not enough information available on the watershed to run a distributed model. But all lumped models greatly simplify the complex processes of the hydrologic cycle. To generate more spread in the hydrologic ensemble predictions, multi-model ensembles have been considered. In this study, the aim is to propose and analyse a method that gives an ensemble streamflow prediction that properly represents the forecast probabilities and reduced ensemble bias. To achieve this, three simple lumped models are used to generate an ensemble. These will also be combined using multi-model averaging techniques, which generally generate a more accurate hydrogram than the best of the individual models in simulation mode. This new predictive combined hydrogram is added to the ensemble, thus creating a large ensemble which may improve the variability while also improving the ensemble mean bias. The quality of the predictions is then assessed on different periods: 2 weeks, 1 month, 3 months and 6 months using a PIT Histogram of the percentiles of the real observation volumes with respect to the volumes of the ensemble members. Initially, the models were run using historical weather data to generate synthetic flows. This worked for individual models, but not for the multi-model and for the large ensemble. Consequently, by performing data assimilation at each prediction period and thus adjusting the initial states of the models, the PIT Histogram could be constructed using the observed flows while allowing the use of the multi-model predictions. The under-dispersion has been

  3. Sensitivity studies on the multi-sensor conductivity probe measurement technique for two-phase flows

    Energy Technology Data Exchange (ETDEWEB)

    Worosz, Ted [Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, 230 Reber Building, University Park, PA 16802 (United States); Bernard, Matt [The United States Nuclear Regulatory Commission, 11545 Rockville Pike, Rockville, MD 20852 (United States); Kong, Ran; Toptan, Aysenur [Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, 230 Reber Building, University Park, PA 16802 (United States); Kim, Seungjin, E-mail: skim@psu.edu [Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, 230 Reber Building, University Park, PA 16802 (United States); Hoxie, Chris [The United States Nuclear Regulatory Commission, 11545 Rockville Pike, Rockville, MD 20852 (United States)

    2016-12-15

    Highlights: • Revised conductivity probe circuit to eliminate signal “ghosting” among sensors. • Higher sampling frequencies suggested for bubble number frequency and a{sub i} measurements. • Two-phase parameter sensitivity to measurement duration and bubble number investigated. • Sensors parallel to pipe wall recommended for symmetric bubble velocity measurements. • Sensor separation distance ratio (s/d) greater than four minimizes bubble velocity error. - Abstract: The objective of this study is to advance the local multi-sensor conductivity probe measurement technique through systematic investigation into several practical aspects of a conductivity probe measurement system. Firstly, signal “ghosting” among probe sensors is found to cause artificially high bubble velocity measurements and low interfacial area concentration (a{sub i}) measurements that depend on sampling frequency and sensor impedance. A revised electrical circuit is suggested to eliminate this artificial variability. Secondly, the sensitivity of the probe measurements to sampling frequency is investigated in 13 two-phase flow conditions with superficial liquid and gas velocities ranging from 1.00–5.00 m/s and 0.17–2.0 m/s, respectively. With increasing gas flow rate, higher sampling frequencies, greater than 100 kHz in some cases, are required to adequately capture the bubble number frequency and a{sub i} measurements. This trend is due to the increase in gas velocity and the transition to the slug flow regime. Thirdly, the sensitivity of the probe measurements to the measurement duration as well as the sample number is investigated for the same flow conditions. Measurements of both group-I (spherical/distorted) and group-II (cap/slug/churn-turbulent) bubbles are found to be relatively insensitive to both the measurement duration and the number of bubbles, as long as the measurements are made for a duration long enough to capture a collection of samples characteristic to a

  4. Model for Generation of Neutrons in a Compact Diode with Laser-Plasma Anode and Suppression of Electron Conduction Using a Permanent Cylindrical Magnet

    Science.gov (United States)

    Shikanov, A. E.; Vovchenko, E. D.; Kozlovskii, K. I.; Rashchikov, V. I.; Shatokhin, V. L.

    2018-04-01

    A model for acceleration of deuterons and generation of neutrons in a compact laser-plasma diode with electron isolation using magnetic field generated by a hollow cylindrical permanent magnet is presented. Experimental and computer-simulated neutron yields are compared for the diode structure under study. An accelerating neutron tube with a relatively high neutron generation efficiency can be constructed using suppression of electron conduction with the aid of a magnet placed in the vacuum volume.

  5. Flyweight, Superelastic, Electrically Conductive, and Flame-Retardant 3D Multi-Nanolayer Graphene/Ceramic Metamaterial.

    Science.gov (United States)

    Zhang, Qiangqiang; Lin, Dong; Deng, Biwei; Xu, Xiang; Nian, Qiong; Jin, Shengyu; Leedy, Kevin D; Li, Hui; Cheng, Gary J

    2017-07-01

    A ceramic/graphene metamaterial (GCM) with microstructure-derived superelasticity and structural robustness is achieved by designing hierarchical honeycomb microstructures, which are composited with two brittle constituents (graphene and ceramic) assembled in multi-nanolayer cellular walls. Attributed to the designed microstructure, well-interconnected scaffolds, chemically bonded interface, and coupled strengthening effect between the graphene framework and the nanolayers of the Al 2 O 3 ceramic (NAC), the GCM demonstrates a sequence of multifunctional properties simultaneously that have not been reported for ceramics and ceramics-matrix-composite structures, such as flyweight density, 80% reversible compressibility, high fatigue resistance, high electrical conductivity, and excellent thermal-insulation/flame-retardant performance simultaneously. The 3D well-ordered graphene aerogel templates are strongly coupled with the NAC by the chemically bonded interface, exhibiting mutual strengthening, compatible deformability, and a linearly dependent relationship between the density and Young's modulus. Considerable size effects of the ceramic nanolayers on the mechanical properties are revealed in these ceramic-based metamaterials. The designed hierarchical honeycomb graphene with a fourth dimensional control of the ceramic nanolayers on new ways to scalable fabrication of advanced multifunctional ceramic composites with controllable design suggest a great potential in applications of flexible conductors, shock/vibration absorbers, thermal shock barriers, thermal insulation/flame-retardant skins, and porous microwave-absorbing coatings. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Multi-objective optimization of distributed generation with voltage ...

    African Journals Online (AJOL)

    ... and line power capacity limit. In this paper, it is analyzed that voltage step constraint affects the location, size and power factor of DG in distribution network. The studies are carried out for 17-bus, 38-bus and 76-bus distribution systems. Keywords: Distributed generation, distribution system, distributed generation planning, ...

  7. Electrically conductive poly-ɛ-caprolactone/polyethylene glycol/multi-wall carbon nanotube nanocomposite scaffolds coated with fibrin glue for myocardial tissue engineering

    Science.gov (United States)

    Mehdikhani, Mehdi; Ghaziof, Sharareh

    2018-01-01

    In this research, poly-ɛ-caprolactone (PCL), polyethylene glycol (PEG), multi-wall carbon nanotubes (MWCNTs), and nanocomposite scaffolds containing 0.5 and 1% (w/w) MWCNTs coated with fibrin glue (FG) were prepared via solvent casting and freeze-drying technique for cardiac tissue engineering. Scanning electron microscopy, transmission electron microscopy, Fourier transform-infrared spectroscopy, and X-ray diffraction were used to characterize the samples. Furthermore, mechanical properties, electrical conductivity, degradation, contact angle, and cytotoxicity of the samples were evaluated. Results showed the uniform distribution of the MWCNTs with some aggregates in the prepared nanocomposite scaffolds. The scaffolds containing 1% (w/w) MWCNTs with and without FG coating illustrated optimum modulus of elasticity, high electrical conductivity, and wettability compared with PCL/PEG and PCL/PEG/0.5%(w/w) MWCNTs' scaffolds. FG coating enhanced electrical conductivity and cell response, and increased wettability of the constructs. The prepared scaffolds were degraded significantly after 60 days of immersion in PBS. Meanwhile, the nanocomposite containing 1% (w/w) MWCNTs with FG coating (S3) showed proper spreading and viability of the myoblasts seeded on it after 1, 4, and 7 days of culture. The scaffold containing 1% (w/w) MWCNTs with FG coating demonstrated optimal properties including acceptable mechanical properties, proper wettability, high electrical conductivity, satisfactory degradation, and excellent myoblasts response to it.

  8. Research in the field of development of a new generation of metal-processing machines

    Directory of Open Access Journals (Sweden)

    L.Tanovič

    2017-12-01

    Full Text Available The paper presents a review of research in the field of development of a new generation of metal-working machines for manufacturing high-precision products with dimensions of several micrometers from various materials. Presented are several new, newly created micro-machines that have the ability to manufacture products of a wide range. Studies in the field of metalworking machines and robots of a new generation with parallel kinematics, creation of machining systems for multi-axis machining, improvement and application of controllable systems, testing of processing systems in production conditions, which are conducted at the Machine-Building Faculty of the Belgrade University (Serbia are considered.

  9. Multi-generational stewardship of plutonium

    International Nuclear Information System (INIS)

    Pillay, K.K.S.

    1997-01-01

    The post-cold war era has greatly enhanced the interest in the long-term stewardship of plutonium. The management of excess plutonium from proposed nuclear weapons dismantlement has been the subject of numerous intellectual discussions during the past several years. In this context, issues relevant to long-term management of all plutonium as a valuable energy resource are also being examined. While there are differing views about the future role of plutonium in the economy, there is a recognition of the environmental and health related problems and proliferation potentials of weapons-grade plutonium. The long-term management of plutonium as an energy resource will require a new strategy to maintain stewardship for many generations to come

  10. Application of Electromagnetic Induction to Monitor Changes in Soil Electrical Conductivity Profiles in Arid Agriculture

    KAUST Repository

    Jadoon, K.Z.

    2015-09-06

    In this research, multi-configuration electromagnetic induction (EMI) measurements were conducted in a corn field to estimate variation in soil electrical conductivity profiles in the roots zone. Electromagnetic forward model based on the full solution of Maxwell\\'s equation was used to simulate the apparent electrical conductivity measured with EMI system (the CMD mini-Explorer). Joint inversion of multi-configuration EMI measurements were performed to estimate the vertical soil electrical conductivity profiles. The inversion minimizes the misfit between the measured and modeled soil apparent electrical conductivity by DiffeRential Evolution Adaptive Metropolis (DREAM) algorithm, which is based on Bayesain approach. Results indicate that soil electrical conductivity profiles have low values close to the corn plants, which indicates loss of soil moisture due to the root water uptake. These results offer valuable insights into future potential and emerging challenges in the development of joint analysis of multi-configuration EMI measurements to retrieve effective soil electrical conductivity profiles.

  11. Engineering design of plasma generation devices using Elmer finite element simulation methods

    Directory of Open Access Journals (Sweden)

    Daniel Bondarenko

    2017-02-01

    Full Text Available Plasma generation devices are important technology for many engineering disciplines. The process for acquiring experience for designing plasma devices requires practice, time, and the right tools. The practice and time depend on the individual and the access to the right tools can be a limiting factor to achieve experience and to get an idea on the possible risks. The use of Elmer finite element method (FEM software for verifying plasma engineering design is presented as an accessible tool that can help modeling multi-physics and verifying plasma generation devices. Furthermore, Elmer FEM will be suitable for experienced engineer and can be used for determining the risks in a design or a process that use plasma. A physical experiment was conducted to demonstrate new features of plasma generation technology where results are compared with plasma simulation using Elmer FEM.

  12. Multi-material micro-electromechanical fibers with bendable functional domains

    Science.gov (United States)

    Nguyen-Dang, Tung; Page, Alexis G.; Qu, Yunpeng; Volpi, Marco; Yan, Wei; Sorin, Fabien

    2017-04-01

    The integration of increasingly complex functionalities within thermally drawn multi-material fibers is heralding a novel path towards advanced soft electronics and smart fabrics. Fibers capable of electronic, optoelectronic, piezoelectric or energy harvesting functions are created by assembling new materials in intimate contact within increasingly complex architectures. Thus far, however, the opportunities associated with the integration of cantilever-like structures with freely moving functional domains within multi-material fibers have not been explored. Used extensively in the micro-electromechanical system (MEMS) technology, electro-mechanical transductance from moving and bendable domains is used in a myriad of applications. In this article we demonstrate the thermal drawing of micro-electromechanical fibers (MEMF) that can detect and localize pressure with high accuracy along their entire length. This ability results from an original cantilever-like design where a freestanding electrically conductive polymer composite film bends under an applied pressure. As it comes into contact with another conducting domain, placed at a prescribed position in the fiber cross-section, an electrical signal is generated. We show that by a judicious choice of materials and electrical connectivity, this signal can be uniquely related to a position along the fiber axis. We establish a model that predicts the position of a local touch from the measurement of currents generated in the 1D MEMF device, and demonstrate an excellent agreement with the experimental data. This ability to detect and localize touch over large areas, curved surfaces and textiles holds significant opportunities in robotics and prosthetics, flexible electronic interfaces, and medical textiles. , which features invited work from the best early-career researchers working within the scope of J. Phys. D. This project is part of the Journal of Physics series’ 50th anniversary celebrations in 2017. Fabien Sorin

  13. 1 ms pulse beam generation and acceleration by photo-cathode RF gun

    International Nuclear Information System (INIS)

    Watanabe, Ken; Hayano, Hitoshi; Urakawa, Jyunji

    2012-01-01

    We report successful generation of 1 ms long pulse and multi-bunch electron beam by a normal conducting photo-cathode RF gun at KEK-STF (Superconducting accelerator Test Facility). The 1 ms long Pulse beam generated by the RF gun is delivered to the injection line to examine stable acceleration and precise RF control. The 1 ms pulse beam is also used to demonstrate high brightness X-ray generation by inverse laser Compton scattering which will be also carried out at STF, supported by MEXT Quantum Beam project. The RF gun cavity has been fabricated by DESY-FNAL-KEK collaboration. Performing high power RF process and ethanol rinse to the cavity, a stable operation of the cavity up to 4.0 MW RF input power with ∼1 ms pulse length was achieved by keeping even low dark current. The beam generation test has been started since February 2012, 1 ms pulse was generated in March 2012. We explain about the STF injector and report the basic property of this 1 ms beam generation. (author)

  14. A Multi-Objective Unit Commitment Model for Setting Carbon Tax to Reduce CO2 Emission: Thailand's Electricity Generation Case

    Directory of Open Access Journals (Sweden)

    Nuchjarin Intalar

    2015-07-01

    Full Text Available Carbon tax policy is a cost-effective instrument for emission reduction. However, setting the carbon tax is one of the challenging task for policy makers as it will lead to higher price of emission-intensive sources especially the utility price. In a large-scale power generation system, minimizing the operational cost and the environmental impact are conflicting objectives and it is difficult to find the compromise solution. This paper proposes a methodology of finding a feasible carbon tax rate on strategic level using the operational unit commitment model. We present a multi-objective mixed integer linear programming model to solve the unit commitment problem and consider the environmental impacts. The methodology of analyzing of the effect of carbon tax rates on the power generation, operating cost, and CO2 emission is also provided. The trade-off relationship between total operating cost and total CO2 emission is presented in the Pareto-optimal curve to analyze the feasible carbon tax rate that is influencing on electricity operating cost. The significant outcome of this paper is a modeling framework for the policy makers to determine the possible carbon tax that can be imposed on the electricity generation.

  15. Solving binary-state multi-objective reliability redundancy allocation series-parallel problem using efficient epsilon-constraint, multi-start partial bound enumeration algorithm, and DEA

    International Nuclear Information System (INIS)

    Khalili-Damghani, Kaveh; Amiri, Maghsoud

    2012-01-01

    In this paper, a procedure based on efficient epsilon-constraint method and data envelopment analysis (DEA) is proposed for solving binary-state multi-objective reliability redundancy allocation series-parallel problem (MORAP). In first module, a set of qualified non-dominated solutions on Pareto front of binary-state MORAP is generated using an efficient epsilon-constraint method. In order to test the quality of generated non-dominated solutions in this module, a multi-start partial bound enumeration algorithm is also proposed for MORAP. The performance of both procedures is compared using different metrics on well-known benchmark instance. The statistical analysis represents that not only the proposed efficient epsilon-constraint method outperform the multi-start partial bound enumeration algorithm but also it improves the founded upper bound of benchmark instance. Then, in second module, a DEA model is supplied to prune the generated non-dominated solutions of efficient epsilon-constraint method. This helps reduction of non-dominated solutions in a systematic manner and eases the decision making process for practical implementations. - Highlights: ► A procedure based on efficient epsilon-constraint method and DEA was proposed for solving MORAP. ► The performance of proposed procedure was compared with a multi-start PBEA. ► Methods were statistically compared using multi-objective metrics.

  16. Multi-Scale Multi-physics Methods Development for the Calculation of Hot-Spots in the NGNP

    International Nuclear Information System (INIS)

    Downar, Thomas; Seker, Volkan

    2013-01-01

    Radioactive gaseous fission products are released out of the fuel element at a significantly higher rate when the fuel temperature exceeds 1600°C in high-temperature gas-cooled reactors (HTGRs). Therefore, it is of paramount importance to accurately predict the peak fuel temperature during all operational and design-basis accident conditions. The current methods used to predict the peak fuel temperature in HTGRs, such as the Next-Generation Nuclear Plant (NGNP), estimate the average fuel temperature in a computational mesh modeling hundreds of fuel pebbles or a fuel assembly in a pebble-bed reactor (PBR) or prismatic block type reactor (PMR), respectively. Experiments conducted in operating HTGRs indicate considerable uncertainty in the current methods and correlations used to predict actual temperatures. The objective of this project is to improve the accuracy in the prediction of local 'hot' spots by developing multi-scale, multi-physics methods and implementing them within the framework of established codes used for NGNP analysis.The multi-scale approach which this project will implement begins with defining suitable scales for a physical and mathematical model and then deriving and applying the appropriate boundary conditions between scales. The macro scale is the greatest length that describes the entire reactor, whereas the meso scale models only a fuel block in a prismatic reactor and ten to hundreds of pebbles in a pebble bed reactor. The smallest scale is the micro scale--the level of a fuel kernel of the pebble in a PBR and fuel compact in a PMR--which needs to be resolved in order to calculate the peak temperature in a fuel kernel.

  17. Multi-Scale Multi-physics Methods Development for the Calculation of Hot-Spots in the NGNP

    Energy Technology Data Exchange (ETDEWEB)

    Downar, Thomas [Univ. of Michigan, Ann Arbor, MI (United States); Seker, Volkan [Univ. of Michigan, Ann Arbor, MI (United States)

    2013-04-30

    Radioactive gaseous fission products are released out of the fuel element at a significantly higher rate when the fuel temperature exceeds 1600°C in high-temperature gas-cooled reactors (HTGRs). Therefore, it is of paramount importance to accurately predict the peak fuel temperature during all operational and design-basis accident conditions. The current methods used to predict the peak fuel temperature in HTGRs, such as the Next-Generation Nuclear Plant (NGNP), estimate the average fuel temperature in a computational mesh modeling hundreds of fuel pebbles or a fuel assembly in a pebble-bed reactor (PBR) or prismatic block type reactor (PMR), respectively. Experiments conducted in operating HTGRs indicate considerable uncertainty in the current methods and correlations used to predict actual temperatures. The objective of this project is to improve the accuracy in the prediction of local "hot" spots by developing multi-scale, multi-physics methods and implementing them within the framework of established codes used for NGNP analysis.The multi-scale approach which this project will implement begins with defining suitable scales for a physical and mathematical model and then deriving and applying the appropriate boundary conditions between scales. The macro scale is the greatest length that describes the entire reactor, whereas the meso scale models only a fuel block in a prismatic reactor and ten to hundreds of pebbles in a pebble bed reactor. The smallest scale is the micro scale--the level of a fuel kernel of the pebble in a PBR and fuel compact in a PMR--which needs to be resolved in order to calculate the peak temperature in a fuel kernel.

  18. Concepts for space nuclear multi-mode reactors

    International Nuclear Information System (INIS)

    Myrabo, L.; Botts, T.E.; Powell, J.R.

    1983-01-01

    A number of nuclear multi-mode reactor power plants are conceptualized for use with solid core, fixed particle bed and rotating particle bed reactors. Multi-mode systems generate high peak electrical power in the open cycle mode, with MHD generator or turbogenerator converters and cryogenically stored coolants. Low level stationkeeping power and auxiliary reactor cooling (i.e., for the removal of reactor afterheat) are provided in a closed cycle mode. Depending on reactor design, heat transfer to the low power converters can be accomplished by heat pipes, liquid metal coolants or high pressure gas coolants. Candidate low power conversion cycles include Brayton turbogenerator, Rankine turbogenerator, thermoelectric and thermionic approaches. A methodology is suggested for estimating the system mass of multi-mode nuclear power plants as a function of peak electric power level and required mission run time. The masses of closed cycle nuclear and open cycle chemical power systems are briefly examined to identify the regime of superiority for nuclear multi-mode systems. Key research and technology issues for such power plants are also identified

  19. Solar fuels generator

    Science.gov (United States)

    Lewis, Nathan S.; Spurgeon, Joshua M.

    2016-10-25

    The solar fuels generator includes an ionically conductive separator between a gaseous first phase and a second phase. A photoanode uses one or more components of the first phase to generate cations during operation of the solar fuels generator. A cation conduit is positioned provides a pathway along which the cations travel from the photoanode to the separator. The separator conducts the cations. A second solid cation conduit conducts the cations from the separator to a photocathode.

  20. Multi-boiling Heat Transfer Analysis of a Convective Straight Fin with Temperature-Dependent Thermal Properties and Internal Heat Generation

    Directory of Open Access Journals (Sweden)

    Gbeminiyi Sobamowo

    2017-10-01

    Full Text Available In this study, by using the finite volume method, the heat transfer in a convective straight fin with temperature-dependent thermal properties and an internal heat generation under multi-boiling heat transfer modes are analyzed. In this regard, the local heat transfer coefficient is considered to vary within a power-law function of temperature. In the present study, the coexistence of all the boiling modes is taken into consideration. The developed heat transfer models and the corresponding numerical solutions are used to investigate the effects of various thermo-geometric parameters on the thermal performance of the longitudinal rectangular fin. The results shows that the fin temperature distribution, the total heat transfer, and the fin efficiency are significantly affected by the thermo-geometric parameters of the fin and the internal heat generation within the fin. The obtained results can provide a platform for improvements in the design of the fin in the heat transfer equipment.

  1. Multi-objective analysis of impacts of distributed generation placement on the operational characteristics of networks for distribution system planning

    Energy Technology Data Exchange (ETDEWEB)

    Barin, Alexandre; Pozzatti, Luis F.; Canha, Luciane N.; Abaide, Alzenira R. [Federal University of Santa Maria - UFSM, Post-graduation Program of Electric Engineering - PPGEE, Center of Studies of Energy and Environment - CEEMA, Santa Maria, RS (Brazil); Machado, Ricardo Q. [University of Sao Paulo - USP, Sao Carlos, SP (Brazil); Arend, Gustavo [State Electric Energy Company - CEEE-D, Division of Distribution, Porto Alegre, RS (Brazil)

    2010-12-15

    Recent advances in energy technology generation and new directions in electricity regulation have made distributed generation (DG) more widespread, with consequent significant impacts on the operational characteristics of distribution networks. For this reason, new methods for identifying such impacts are needed, together with research and development of new tools and resources to maintain and facilitate continued expansion towards DG. This paper presents a study aimed at determining appropriate DG sites for distribution systems. The main considerations which determine DG sites are also presented, together with an account of the advantages gained from correct DG placement. The paper intends to define some quantitative and qualitative parameters evaluated by Digsilent registered, GARP3 registered and DSA-GD software. A multi-objective approach based on the Bellman-Zadeh algorithm and fuzzy logic is used to determine appropriate DG sites. The study also aims to find acceptable DG locations both for distribution system feeders, as well as for nodes inside a given feeder. (author)

  2. Generating Long Scale-Length Plasma Jets Embedded in a Uniform, Multi-Tesla Magnetic-Field

    Science.gov (United States)

    Manuel, Mario; Kuranz, Carolyn; Rasmus, Alex; Klein, Sallee; Fein, Jeff; Belancourt, Patrick; Drake, R. P.; Pollock, Brad; Hazi, Andrew; Park, Jaebum; Williams, Jackson; Chen, Hui

    2013-10-01

    Collimated plasma jets emerge in many classes of astrophysical objects and are of great interest to explore in the laboratory. In many cases, these astrophysical jets exist within a background magnetic field where the magnetic pressure approaches the plasma pressure. Recent experiments performed at the Jupiter Laser Facility utilized a custom-designed solenoid to generate the multi-tesla fields necessary to achieve proper magnetization of the plasma. Time-gated interferometry, Schlieren imaging, and proton radiography were used to characterize jet evolution and collimation under varying degrees of magnetization. Experimental results will be presented and discussed. This work is funded by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, grant number DE-NA0001840, by the National Laser User Facility Program, grant number DE-NA0000850, by the Predictive Sciences Academic Alliances Program in NNSA-ASC, grant number DEFC52-08NA28616, and by NASA through Einstein Postdoctoral Fellowship grant number PF3-140111 awarded by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for NASA under contract NAS8-03060.

  3. Next Generation Multi-mode Remote Sensing Radar

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this work is to demonstrate a new generation of digital beamforming synthetic aperture instrument technology (DBSAR-2) which has the potential of...

  4. Development of Curriculum Content for a Unique Career Ladder Multi-Entry/Multi-Exit Nursing Program. Final Report.

    Science.gov (United States)

    Rosbach, Ellen M.

    A project was undertaken to develop the curriculum content for a unique career ladder multi-entry/multi-exit nursing program that would provide training for nurse aides, practical nurses, and registered nurses. The major objectives of the project were to conduct a review of the literature on curriculum materials presently in use, to develop 11…

  5. Progress and challenges in the development and qualification of multi-level multi-physics coupled methodologies for reactor analysis

    International Nuclear Information System (INIS)

    Ivanov, K.; Avramova, M.

    2007-01-01

    Current trends in nuclear power generation and regulation as well as the design of next generation reactor concepts along with the continuing computer technology progress stimulate the development, qualification and application of multi-physics multi-scale coupled code systems. The efforts have been focused on extending the analysis capabilities by coupling models, which simulate different phenomena or system components, as well as on refining the scale and level of detail of the coupling. This paper reviews the progress made in this area and outlines the remaining challenges. The discussion is illustrated with examples based on neutronics/thermohydraulics coupling in the reactor core modeling. In both fields recent advances and developments are towards more physics-based high-fidelity simulations, which require implementation of improved and flexible coupling methodologies. First, the progresses in coupling of different physics codes along with the advances in multi-level techniques for coupled code simulations are discussed. Second, the issues related to the consistent qualification of coupled multi-physics and multi-scale code systems for design and safety evaluation are presented. The increased importance of uncertainty and sensitivity analysis are discussed along with approaches to propagate the uncertainty quantification between the codes. The incoming OECD LWR Uncertainty Analysis in Modeling (UAM) benchmark is the first international activity to address this issue and it is described in the paper. Finally, the remaining challenges with multi-physics coupling are outlined. (authors)

  6. Progress and challenges in the development and qualification of multi-level multi-physics coupled methodologies for reactor analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, K.; Avramova, M. [Pennsylvania State Univ., University Park, PA (United States)

    2007-07-01

    Current trends in nuclear power generation and regulation as well as the design of next generation reactor concepts along with the continuing computer technology progress stimulate the development, qualification and application of multi-physics multi-scale coupled code systems. The efforts have been focused on extending the analysis capabilities by coupling models, which simulate different phenomena or system components, as well as on refining the scale and level of detail of the coupling. This paper reviews the progress made in this area and outlines the remaining challenges. The discussion is illustrated with examples based on neutronics/thermohydraulics coupling in the reactor core modeling. In both fields recent advances and developments are towards more physics-based high-fidelity simulations, which require implementation of improved and flexible coupling methodologies. First, the progresses in coupling of different physics codes along with the advances in multi-level techniques for coupled code simulations are discussed. Second, the issues related to the consistent qualification of coupled multi-physics and multi-scale code systems for design and safety evaluation are presented. The increased importance of uncertainty and sensitivity analysis are discussed along with approaches to propagate the uncertainty quantification between the codes. The incoming OECD LWR Uncertainty Analysis in Modeling (UAM) benchmark is the first international activity to address this issue and it is described in the paper. Finally, the remaining challenges with multi-physics coupling are outlined. (authors)

  7. Hybrid Robust Multi-Objective Evolutionary Optimization Algorithm

    Science.gov (United States)

    2009-03-10

    xfar by xint. Else, generate a new individual, using the Sobol pseudo- random sequence generator within the upper and lower bounds of the variables...12. Deb, K., Multi-Objective Optimization Using Evolutionary Algorithms, John Wiley & Sons. 2002. 13. Sobol , I. M., "Uniformly Distributed Sequences

  8. Direction sensitive bending sensors based on multi-wall carbon nanotube/epoxy nanocomposites

    International Nuclear Information System (INIS)

    Wichmann, Malte H G; Buschhorn, Samuel T; Boeger, Lars; Schulte, Karl; Adelung, Rainer

    2008-01-01

    In the present work, a direction sensitive bending strain sensor consisting of a single block of epoxy/multi-wall carbon nanotube composite was developed. Moreover, the manufacturing could be realized in a straightforward single-step processing route. The directional sensitivity to bending deformations is related to the change in electrical resistance, which becomes positive or negative, depending on the direction of bending deflection. This effect is achieved by generating a gradient in electrical conductivity throughout the material. The resistance versus strain behaviour of these devices is investigated in detail and related to the microstructure of the nanocomposites.

  9. Development of the Mo loading apparatus for adsorbing high level 99Mo to PZC and packing in 99mTc generator column

    International Nuclear Information System (INIS)

    Hishinuma, Yukio; Ohmori, Hiroyuki; Noguchi, Tuneyuki; Tatenuma, Katsuyoshi; Genka, Tsuguo; Machi, Sueo

    2006-01-01

    For developing the automatic system to produce the PZC- 99m Tc generator column based on (n, gamma) method, we developed and fabricated the proto-type apparatus for semi hot test to prepare and pack PZC adsorbed 99 Mo produced by (n, gamma) method into the generator column; PZC is Mo adsorbent with practical performance for (n, gamma) 99m Tc generator with high 99 Mo adsorption and high 99m Tc elution. For conducting the constant supply and delivery of 99m Tc generator, it is necessary to establish the technology of (n, gamma) method 99m Tc generator using PZC and to develop the fabrication system for 99 Mo loading to PZC and packing the 99m Tc generator column. By the reason, we are developing the Mo loading apparatus. In order to automatically conduct the process of 99 Mo adsorption to PZC and PZC- 99 Mo packing into the generator column, based on one channel system developed by JAERI-KAKEN at 3 years ago, an advanced automatic loading system functioned with 8 channels was developed as FNCA project proceeded by the core with Kaken Co. and JAIF for realizing a mass production of 99m Tc generators, and moreover the Japanese patent regarding the PZC- 99m Tc generator including the automatic loading system of 99 Mo to PZC and making 99m Tc generator columns has already been applied with joint applicants of BATAN and Kaken Co. Regarding the multi-type Mo loading apparatus mentioned above, we set it up in a hot of BATAN at December 2003 year. In this report, we will introduce mainly about the multi-channel automatic loading system of 99 Mo. (author)

  10. Congenital and Adquired Abnormalities of Pediatric Trachea and Main-Steam Bronchi

    International Nuclear Information System (INIS)

    Vargas Bazurto, Maria Catalina; Varon, Humberto; Perez Alvarado, Maria Carolina; Puerta Ramirez, Andres Felipe; Ruales Fierro, Franco Libardo

    2011-01-01

    Tracheobronchial tree abnormalities can be first suspected in chest radiography; nonetheless, multidetector row computed tomography imaging constitutes a complementary diagnostic alternative for the evaluation of congenital and acquired tracheobronchial tree anomalies that allows the radiologist a closer approximation toward the correct diagnosis as well as the accurate description of its morphological features and differential diagnosis. We present a review of the main tracheobronchial tree pathology.

  11. A Multi-Period Optimization Model for Service Providers Using Online Reservation Systems: An Application to Hotels.

    Science.gov (United States)

    Xu, Ming; Jiao, Yan; Li, Xiaoming; Cao, Qingfeng; Wang, Xiaoyang

    2015-01-01

    This paper presents a multi-period optimization model for high margin and zero salvage products in online distribution channels with classifying customers based on number of products required. Taking hotel customers as an example, one is regular customers who reserve rooms for one day, and the other is long term stay (LTS) customers who reserve rooms for a number of days. LTS may guarantee a specific amount of demand and generate opportunity income for a certain number of periods, meanwhile with risk of punishment incurred by overselling. By developing an operational optimization model and exploring the effects of parameters on optimal decisions, we suggest that service providers should make decisions based on the types of customers, number of products required, and duration of multi-period to reduce the loss of reputation and obtain more profit; at the same time, multi-period buying customers should buy products early. Finally, the paper conducts a numerical experiment, and the results are consistent with prevailing situations.

  12. A Multi-Period Optimization Model for Service Providers Using Online Reservation Systems: An Application to Hotels

    Science.gov (United States)

    Xu, Ming; Jiao, Yan; Li, Xiaoming; Cao, Qingfeng; Wang, Xiaoyang

    2015-01-01

    This paper presents a multi-period optimization model for high margin and zero salvage products in online distribution channels with classifying customers based on number of products required. Taking hotel customers as an example, one is regular customers who reserve rooms for one day, and the other is long term stay (LTS) customers who reserve rooms for a number of days. LTS may guarantee a specific amount of demand and generate opportunity income for a certain number of periods, meanwhile with risk of punishment incurred by overselling. By developing an operational optimization model and exploring the effects of parameters on optimal decisions, we suggest that service providers should make decisions based on the types of customers, number of products required, and duration of multi-period to reduce the loss of reputation and obtain more profit; at the same time, multi-period buying customers should buy products early. Finally, the paper conducts a numerical experiment, and the results are consistent with prevailing situations. PMID:26147663

  13. Generation Expansion Planning Considering Integrating Large-scale Wind Generation

    DEFF Research Database (Denmark)

    Zhang, Chunyu; Ding, Yi; Østergaard, Jacob

    2013-01-01

    necessitated the inclusion of more innovative and sophisticated approaches in power system investment planning. A bi-level generation expansion planning approach considering large-scale wind generation was proposed in this paper. The first phase is investment decision, while the second phase is production...... optimization decision. A multi-objective PSO (MOPSO) algorithm was introduced to solve this optimization problem, which can accelerate the convergence and guarantee the diversity of Pareto-optimal front set as well. The feasibility and effectiveness of the proposed bi-level planning approach and the MOPSO...

  14. Multi utility - a successful conception for energy supply companies?; Multi-Utility - Erfolgskonzept fuer Energieversorger? Zusammenwachsen der Maerkte

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, C. [LBD-Beratungsgesellschaft mbH, Berlin (Germany)

    2003-06-02

    Multi-utility is seen as the most promising marketing strategy for energy companies. In the future, experts say, only the combined supply of electricity, natural gas, water, waste management and services will allow companies to grow. But are today's multi-utility-products answering the needs of the customers? The author goes further into this question and finds the answer: Multi-utility needs to be further developed. Only products from growth and competition markets can generate additional margins. (orig.) [German] Multi-Utility gilt als die Marketingstrategie fuer Energieversorger. Nur wer zukuenftig Strom, Gas, Wasser, Entsorgung und Service aus einer Hand anbietet, heisst es in der Branche, kann im Markt wachsen. Doch inwieweit entspricht das heutige Multi-Utility-Angebot wirklich dem Kundenbeduerfnis? Die Verfasserin geht dieser Frage nach und kommt zu dem Schluss: Die Multi-Utility-Palette muss weiterentwickelt werden. Nur mit Produkten aus Wachstums- und Wettbewerbsmaerkten kann zusaetzliche Marge generiert werden. (orig.)

  15. A fractional-N frequency synthesizer-based multi-standard I/Q carrier generation system in 0.13 μm CMOS

    International Nuclear Information System (INIS)

    Lou Wenfeng; Geng Zhiqing; Feng Peng; Wu Nanjian

    2011-01-01

    This paper proposes a sigma-delta fractional-N frequency synthesizer-based multi-standard I/Q carrier generation system. With reasonable frequency planning, the system can be used in multi-standard wireless communication applications (GSM, WCDMA, GPRS, TD-SCDMA, WLAN (802.11a/b/g)). The implementation is achieved by a 0.13 μm RF CMOS process. The measured results demonstrate that three quadrature VCOs (QVCO) continuously cover the frequency from 3.1 to 6.1 GHz (65.2%), and through the successive divide-by-2 prescalers to achieve the frequency from 0.75 to 6.1 GHz continuously. The chip was fully integrated with the exception of an off-chip filter. The entire chip area is only 3.78 mm 2 , and the system consumes a 21.7 mA - 1.2 V supply without output buffers. The lock-in time of the PLL frequency synthesizer is less than 4 μs over the entire frequency range with a direct frequency presetting technique and the auxiliary non-volatile memory (NVM) can store the digital configuration signal of the system, including presetting signals to avoid the calibration process case by case. (semiconductor integrated circuits)

  16. A fractional-N frequency synthesizer-based multi-standard I/Q carrier generation system in 0.13 {mu}m CMOS

    Energy Technology Data Exchange (ETDEWEB)

    Lou Wenfeng; Geng Zhiqing; Feng Peng; Wu Nanjian, E-mail: nanjian@semi.ac.cn [Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

    2011-06-15

    This paper proposes a sigma-delta fractional-N frequency synthesizer-based multi-standard I/Q carrier generation system. With reasonable frequency planning, the system can be used in multi-standard wireless communication applications (GSM, WCDMA, GPRS, TD-SCDMA, WLAN (802.11a/b/g)). The implementation is achieved by a 0.13 {mu}m RF CMOS process. The measured results demonstrate that three quadrature VCOs (QVCO) continuously cover the frequency from 3.1 to 6.1 GHz (65.2%), and through the successive divide-by-2 prescalers to achieve the frequency from 0.75 to 6.1 GHz continuously. The chip was fully integrated with the exception of an off-chip filter. The entire chip area is only 3.78 mm{sup 2}, and the system consumes a 21.7 mA - 1.2 V supply without output buffers. The lock-in time of the PLL frequency synthesizer is less than 4 {mu}s over the entire frequency range with a direct frequency presetting technique and the auxiliary non-volatile memory (NVM) can store the digital configuration signal of the system, including presetting signals to avoid the calibration process case by case. (semiconductor integrated circuits)

  17. A Review of the Empirical Generations at Work Research: Implications for School Leaders and Future Research

    Science.gov (United States)

    Edge, Karen

    2014-01-01

    Most schools currently employ three generations of teachers and leaders: Baby Boomers (1946-65), Generation X (1966-80) and Generation Y (1981-2003). However, the implications for school leaders of multi-generational schools remain relatively unexplored. This paper examines the empirical multi-disciplinary generations at work evidence to identify…

  18. Generative mechanistic explanation building in undergraduate molecular and cellular biology

    Science.gov (United States)

    Southard, Katelyn M.; Espindola, Melissa R.; Zaepfel, Samantha D.; Bolger, Molly S.

    2017-09-01

    When conducting scientific research, experts in molecular and cellular biology (MCB) use specific reasoning strategies to construct mechanistic explanations for the underlying causal features of molecular phenomena. We explored how undergraduate students applied this scientific practice in MCB. Drawing from studies of explanation building among scientists, we created and applied a theoretical framework to explore the strategies students use to construct explanations for 'novel' biological phenomena. Specifically, we explored how students navigated the multi-level nature of complex biological systems using generative mechanistic reasoning. Interviews were conducted with introductory and upper-division biology students at a large public university in the United States. Results of qualitative coding revealed key features of students' explanation building. Students used modular thinking to consider the functional subdivisions of the system, which they 'filled in' to varying degrees with mechanistic elements. They also hypothesised the involvement of mechanistic entities and instantiated abstract schema to adapt their explanations to unfamiliar biological contexts. Finally, we explored the flexible thinking that students used to hypothesise the impact of mutations on multi-leveled biological systems. Results revealed a number of ways that students drew mechanistic connections between molecules, functional modules (sets of molecules with an emergent function), cells, tissues, organisms and populations.

  19. Brushless power generating system having reduced conducted emissions in output power

    International Nuclear Information System (INIS)

    Walton, D.N.; Dolan, C.F.; Shah, M.J.

    1991-01-01

    This patent describes a brushless electrical power generating system. It comprises an exciter for producing alternating current from an exciter rotor; a rectifier mounted for rotation with the rotor for producing a rectified control current from the alternating current; a common mode inductor, coupled to the rectifier, for cancelling common mode noise components within the rectified control current; and a main generator, having a rotating field winding mounted on a main generator rotor excited by the control current and producing an alternating current power output from a stator

  20. A semi-automatic image-based close range 3D modeling pipeline using a multi-camera configuration.

    Science.gov (United States)

    Rau, Jiann-Yeou; Yeh, Po-Chia

    2012-01-01

    The generation of photo-realistic 3D models is an important task for digital recording of cultural heritage objects. This study proposes an image-based 3D modeling pipeline which takes advantage of a multi-camera configuration and multi-image matching technique that does not require any markers on or around the object. Multiple digital single lens reflex (DSLR) cameras are adopted and fixed with invariant relative orientations. Instead of photo-triangulation after image acquisition, calibration is performed to estimate the exterior orientation parameters of the multi-camera configuration which can be processed fully automatically using coded targets. The calibrated orientation parameters of all cameras are applied to images taken using the same camera configuration. This means that when performing multi-image matching for surface point cloud generation, the orientation parameters will remain the same as the calibrated results, even when the target has changed. Base on this invariant character, the whole 3D modeling pipeline can be performed completely automatically, once the whole system has been calibrated and the software was seamlessly integrated. Several experiments were conducted to prove the feasibility of the proposed system. Images observed include that of a human being, eight Buddhist statues, and a stone sculpture. The results for the stone sculpture, obtained with several multi-camera configurations were compared with a reference model acquired by an ATOS-I 2M active scanner. The best result has an absolute accuracy of 0.26 mm and a relative accuracy of 1:17,333. It demonstrates the feasibility of the proposed low-cost image-based 3D modeling pipeline and its applicability to a large quantity of antiques stored in a museum.

  1. One registration multi-atlas-based pseudo-CT generation for attenuation correction in PET/MRI

    International Nuclear Information System (INIS)

    Arabi, Hossein; Zaidi, Habib

    2016-01-01

    The outcome of a detailed assessment of various strategies for atlas-based whole-body bone segmentation from magnetic resonance imaging (MRI) was exploited to select the optimal parameters and setting, with the aim of proposing a novel one-registration multi-atlas (ORMA) pseudo-CT generation approach. The proposed approach consists of only one online registration between the target and reference images, regardless of the number of atlas images (N), while for the remaining atlas images, the pre-computed transformation matrices to the reference image are used to align them to the target image. The performance characteristics of the proposed method were evaluated and compared with conventional atlas-based attenuation map generation strategies (direct registration of the entire atlas images followed by voxel-wise weighting (VWW) and arithmetic averaging atlas fusion). To this end, four different positron emission tomography (PET) attenuation maps were generated via arithmetic averaging and VWW scheme using both direct registration and ORMA approaches as well as the 3-class attenuation map obtained from the Philips Ingenuity TF PET/MRI scanner commonly used in the clinical setting. The evaluation was performed based on the accuracy of extracted whole-body bones by the different attenuation maps and by quantitative analysis of resulting PET images compared to CT-based attenuation-corrected PET images serving as reference. The comparison of validation metrics regarding the accuracy of extracted bone using the different techniques demonstrated the superiority of the VWW atlas fusion algorithm achieving a Dice similarity measure of 0.82 ± 0.04 compared to arithmetic averaging atlas fusion (0.60 ± 0.02), which uses conventional direct registration. Application of the ORMA approach modestly compromised the accuracy, yielding a Dice similarity measure of 0.76 ± 0.05 for ORMA-VWW and 0.55 ± 0.03 for ORMA-averaging. The results of quantitative PET analysis followed the same

  2. One registration multi-atlas-based pseudo-CT generation for attenuation correction in PET/MRI

    Energy Technology Data Exchange (ETDEWEB)

    Arabi, Hossein [Geneva University Hospital, Division of Nuclear Medicine and Molecular Imaging, Geneva 4 (Switzerland); Zaidi, Habib [Geneva University Hospital, Division of Nuclear Medicine and Molecular Imaging, Geneva 4 (Switzerland); Geneva University, Geneva Neuroscience Center, Geneva (Switzerland); University of Groningen, University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); University of Southern Denmark, Department of Nuclear Medicine, Odense (Denmark)

    2016-10-15

    The outcome of a detailed assessment of various strategies for atlas-based whole-body bone segmentation from magnetic resonance imaging (MRI) was exploited to select the optimal parameters and setting, with the aim of proposing a novel one-registration multi-atlas (ORMA) pseudo-CT generation approach. The proposed approach consists of only one online registration between the target and reference images, regardless of the number of atlas images (N), while for the remaining atlas images, the pre-computed transformation matrices to the reference image are used to align them to the target image. The performance characteristics of the proposed method were evaluated and compared with conventional atlas-based attenuation map generation strategies (direct registration of the entire atlas images followed by voxel-wise weighting (VWW) and arithmetic averaging atlas fusion). To this end, four different positron emission tomography (PET) attenuation maps were generated via arithmetic averaging and VWW scheme using both direct registration and ORMA approaches as well as the 3-class attenuation map obtained from the Philips Ingenuity TF PET/MRI scanner commonly used in the clinical setting. The evaluation was performed based on the accuracy of extracted whole-body bones by the different attenuation maps and by quantitative analysis of resulting PET images compared to CT-based attenuation-corrected PET images serving as reference. The comparison of validation metrics regarding the accuracy of extracted bone using the different techniques demonstrated the superiority of the VWW atlas fusion algorithm achieving a Dice similarity measure of 0.82 ± 0.04 compared to arithmetic averaging atlas fusion (0.60 ± 0.02), which uses conventional direct registration. Application of the ORMA approach modestly compromised the accuracy, yielding a Dice similarity measure of 0.76 ± 0.05 for ORMA-VWW and 0.55 ± 0.03 for ORMA-averaging. The results of quantitative PET analysis followed the same

  3. Multi-protocol header generation system

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, David A.; Ignatowski, Michael; Jayasena, Nuwan; Loh, Gabriel

    2017-09-05

    A communication device includes a data source that generates data for transmission over a bus, and a data encoder that receives and encodes outgoing data. An encoder system receives outgoing data from a data source and stores the outgoing data in a first queue. An encoder encodes outgoing data with a header type that is based upon a header type indication from a controller and stores the encoded data that may be a packet or a data word with at least one layered header in a second queue for transmission. The device is configured to receive at a payload extractor, a packet protocol change command from the controller and to remove the encoded data and to re-encode the data to create a re-encoded data packet and placing the re-encoded data packet in the second queue for transmission.

  4. Nanostructuring of conduction channels in (In,Ga)As-InP heterostructures: Overcoming carrier generation caused by Ar ion milling

    Science.gov (United States)

    Hortelano, V.; Weidlich, H.; Semtsiv, M. P.; Masselink, W. T.; Ramsteiner, M.; Jahn, U.; Biermann, K.; Takagaki, Y.

    2018-04-01

    Nanometer-sized channels are fabricated in (In,Ga)As-InP heterostructures using Ar ion milling. The ion milling causes spontaneous creation of nanowires, and moreover, electrical conduction of the surface as carriers is generated by sputtering-induced defects. We demonstrate a method to restore electrical isolation in the etched area that is compatible with the presence of the nanochannels. We remove the heavily damaged surface layer using a diluted HCl solution and subsequently recover the crystalline order in the moderately damaged part by annealing. We optimize the HCl concentration to make the removal stop on its own before reaching the conduction channel part. The lateral depletion in the channels is shown to be almost absent.

  5. Biodiesel production from multi feedstock as feed with direct ultrasound assisted

    International Nuclear Information System (INIS)

    Widayat; Satriadi, H.; Nafiega, N. Favian; Dipo, Rheza; Okvitarini; Alimin, A. J.; Ali, Mas Fawzi Mohd

    2015-01-01

    The objective of this study was to optimize of ratio oil type, ratio oil to methanol and catalyst concentration. The optimization was used Central Composite Design (CCD). Biodiesel was produced with multi stock oil as feed and conducted in direct ultrasonic radiation. Biosonic equiped with ultrasonic generator with a frequency of 28 kHz. Biodiesel produced at a pressure of 1 atm, reaction time of 60 min and temperature 60 ° C. The optimum conditions of volume ratio for Palm and Coconut oil 4:1, KOH catalyst concentration 0.3% and methanol to oil mole ratio 7:1. Biodiesel yield was determined under this condition and obtained 81.105%

  6. Biodiesel production from multi feedstock as feed with direct ultrasound assisted

    Energy Technology Data Exchange (ETDEWEB)

    Widayat, E-mail: yayat-99@yahoo.com [Department of Chemical Engineering, Diponegoro University Semarang Indonesia (Indonesia); Center of Biomass and Renewable Energy (C-BIORE) Diponegoro University (Indonesia); Satriadi, H.; Nafiega, N. Favian; Dipo, Rheza; Okvitarini [Department of Chemical Engineering, Diponegoro University Semarang Indonesia (Indonesia); Alimin, A. J.; Ali, Mas Fawzi Mohd [Faculty of Mechanical and Manufacturing Engineering Universiti Tun Hussein Onn Malaysia (UTHM) (Malaysia)

    2015-12-29

    The objective of this study was to optimize of ratio oil type, ratio oil to methanol and catalyst concentration. The optimization was used Central Composite Design (CCD). Biodiesel was produced with multi stock oil as feed and conducted in direct ultrasonic radiation. Biosonic equiped with ultrasonic generator with a frequency of 28 kHz. Biodiesel produced at a pressure of 1 atm, reaction time of 60 min and temperature 60 ° C. The optimum conditions of volume ratio for Palm and Coconut oil 4:1, KOH catalyst concentration 0.3% and methanol to oil mole ratio 7:1. Biodiesel yield was determined under this condition and obtained 81.105%.

  7. Implementation of a novel two-attractor grid multi-scroll chaotic system

    International Nuclear Information System (INIS)

    Xiao-Hua, Luo; Zheng-Wei, Tu; Xi-Rui, Liu; Chang, Cai; Pu, Gong; Yi-Long, Liang

    2010-01-01

    This paper proposed a method of generating two attractors in a novel grid multi-scroll chaotic system. Based on a newly generated three-dimensional system, a two-attractor grid multi-scroll attractor system can be generated by adding two triangular waves and a sign function. Some basic dynamical properties, such as equilibrium points, bifurcations, and phase diagrams, were studied. Furthermore, the system was experimentally confirmed by an electronic circuit. The circuit simulation results and numerical simulation results verified the feasibility of this method. (general)

  8. Multi-layer micro/nanofluid devices with bio-nanovalves

    Science.gov (United States)

    Li, Hao; Ocola, Leonidas E.; Auciello, Orlando H.; Firestone, Millicent A.

    2013-01-01

    A user-friendly multi-layer micro/nanofluidic flow device and micro/nano fabrication process are provided for numerous uses. The multi-layer micro/nanofluidic flow device can comprise: a substrate, such as indium tin oxide coated glass (ITO glass); a conductive layer of ferroelectric material, preferably comprising a PZT layer of lead zirconate titanate (PZT) positioned on the substrate; electrodes connected to the conductive layer; a nanofluidics layer positioned on the conductive layer and defining nanochannels; a microfluidics layer positioned upon the nanofluidics layer and defining microchannels; and biomolecular nanovalves providing bio-nanovalves which are moveable from a closed position to an open position to control fluid flow at a nanoscale.

  9. Comparative study of EBE (Equivalent Bilateral Exchanges) multi-area and Zbus multi-area methods to allocate costs by using the transmission system; Estudo comparativo dos metodos EBE multi-area e Zbus multi-area para alocacao de custos pelo uso do sistema de transmissao

    Energy Technology Data Exchange (ETDEWEB)

    Caparo, J.L.Ch.; Lima, D.A. [Pontificia Universidade Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil). Dept. de Engenharia Eletrica], Emails: jluis@ele.puc-rio.br, delberis@ele.puc-rio.br

    2009-07-01

    This work is dedicated to study and discuss two methods to solve the problem of cost allocation by the use of the transmission system in multi-areas for generators and loads. The EBE multi-area method (EBE MA), which is based on EBE, and the Zbus multi-area method (Zbus MA), which is based on Zbus method to allocate costs by using the transmission system, are presented and discussed. Results, analysis and conclusions were made with the 8-bar system, which allows a good interpretation of the behavior of methods.

  10. High thermal conductivity lossy dielectric using a multi layer configuration

    Science.gov (United States)

    Tiegs, Terry N.; Kiggans, Jr., James O.

    2003-01-01

    Systems and methods are described for loss dielectrics. A loss dielectric includes at least one high dielectric loss layer and at least one high thermal conductivity-electrically insulating layer adjacent the at least one high dielectric loss layer. A method of manufacturing a loss dielectric includes providing at least one high dielectric loss layer and providing at least one high thermal conductivity-electrically insulating layer adjacent the at least one high dielectric loss layer. The systems and methods provide advantages because the loss dielectrics are less costly and more environmentally friendly than the available alternatives.

  11. Effects of MeV Si ions bombardment on the thermoelectric generator from SiO{sub 2}/SiO{sub 2} + Cu and SiO{sub 2}/SiO{sub 2} + Au nanolayered multilayer films

    Energy Technology Data Exchange (ETDEWEB)

    Budak, S., E-mail: satilmis.budak@aamu.edu [Department of Electrical Engineering, Alabama A and M University, Normal, AL (United States); Chacha, J., E-mail: chacha_john79@hotmail.com [Department of Electrical Engineering, Alabama A and M University, Normal, AL (United States); Smith, C., E-mail: cydale@cim.aamu.edu [Center for Irradiation of Materials, Alabama A and M University, Normal, AL (United States); Department of Physics, Alabama A and M University, Normal, AL (United States); Pugh, M., E-mail: marcuspughp@yahoo.com [Department of Electrical Engineering, Alabama A and M University, Normal, AL (United States); Colon, T. [Department of Mechanical Engineering, Alabama A and M University, Normal, AL (United States); Heidary, K., E-mail: kaveh.heidary@aamu.edu [Department of Electrical Engineering, Alabama A and M University, Normal, AL (United States); Johnson, R.B., E-mail: barry@w4wb.com [Department of Physics, Alabama A and M University, Normal, AL (United States); Ila, D., E-mail: ila@cim.aamu.edu [Center for Irradiation of Materials, Alabama A and M University, Normal, AL (United States); Department of Physics, Alabama A and M University, Normal, AL (United States)

    2011-12-15

    The defects and disorder in the thin films caused by MeV ions bombardment and the grain boundaries of these nanoscale clusters increase phonon scattering and increase the chance of an inelastic interaction and phonon annihilation. We prepared the thermoelectric generator devices from 100 alternating layers of SiO{sub 2}/SiO{sub 2} + Cu multi-nano layered superlattice films at the total thickness of 382 nm and 50 alternating layers of SiO{sub 2}/SiO{sub 2} + Au multi-nano layered superlattice films at the total thickness of 147 nm using the physical vapor deposition (PVD). Rutherford Backscattering Spectrometry (RBS) and RUMP simulation have been used to determine the stoichiometry of the elements of SiO{sub 2}, Cu and Au in the multilayer films and the thickness of the grown multi-layer films. The 5 MeV Si ions bombardments have been performed using the AAMU-Center for Irradiation of Materials (CIM) Pelletron ion beam accelerator to make quantum (nano) dots and/or quantum (quantum) clusters in the multilayered superlattice thin films to decrease the cross plane thermal conductivity, increase the cross plane Seebeck coefficient and cross plane electrical conductivity. To characterize the thermoelectric generator devices before and after Si ion bombardments we have measured Seebeck coefficient, cross-plane electrical conductivity, and thermal conductivity in the cross-plane geometry for different fluences.

  12. Argon Plasma Coagulation Combined with Covered Stent Placement for Management of Tracheobronchial Stenoses/occlusions as well as Esophagorespiratory Fistulas

    Directory of Open Access Journals (Sweden)

    Hongwu WANG

    2010-09-01

    Full Text Available Background and objective It is a complex problem and difficult treatment for tracheobronchial stenoses/occlusions involving in carina. The aim of this study is to investigate the feasibility and efficiency of argon plasma coagulation (APC and bifurcated covered Z-type stents (CZTS placement for the treatment of tracheobronchus stenoses and esophagorespiratory fistula (ERF. Methods Thirty-two cases with airway disorders were retrospectively reviewed for the treatment of APC and CZTS placement. Under the bronchoscopic guidance, APC was first given in patients with airway stenoses, then CZTS was placed under the fluoroscopic and flexible bronchoscopic guidance either with airway stenoses or ERF. Results APC was first given in 19 patients with airway stenoses. Airway structures were significantly improved after APC procedure (57.4%-72.1% before APC vs 12.8%-25.8% after APC. Thirty-two CZTS were technically successfully placed in 30 out of 32 cases involving in carinal bifurcation. After APC and stent placement, short breath index was significantly reduced and karnofsky physical score (KPS increased obviously. The endobronchial defects were successfully palliated with bifurcated CZTS placed under fluoroscopy and flexible bronchoscopy in 12 out of 13 patients with ERFs. There is no bleeding introprocedure. Mucous retention was very common in all types of the stents less than 2 weeks after stenting, which required debridement by bronchoscopy and could be prevented by normal saline solution nebulizations. Granuloma developed at the ends of stents after 1 month of stenting which all of them were treated successfully with APC and CO2 cryosurgery. Conclusion Utilization of APC and retrieval bifurcated CZTS placement is a simple and safe protocol for the management of airway complex stenoses involving the tracheal carina and ERF.

  13. The exposure of Sydney (Australia) to earthquake-generated tsunamis, storms and sea level rise: a probabilistic multi-hazard approach.

    Science.gov (United States)

    Dall'Osso, F; Dominey-Howes, D; Moore, C; Summerhayes, S; Withycombe, G

    2014-12-10

    Approximately 85% of Australia's population live along the coastal fringe, an area with high exposure to extreme inundations such as tsunamis. However, to date, no Probabilistic Tsunami Hazard Assessments (PTHA) that include inundation have been published for Australia. This limits the development of appropriate risk reduction measures by decision and policy makers. We describe our PTHA undertaken for the Sydney metropolitan area. Using the NOAA NCTR model MOST (Method for Splitting Tsunamis), we simulate 36 earthquake-generated tsunamis with annual probabilities of 1:100, 1:1,000 and 1:10,000, occurring under present and future predicted sea level conditions. For each tsunami scenario we generate a high-resolution inundation map of the maximum water level and flow velocity, and we calculate the exposure of buildings and critical infrastructure. Results indicate that exposure to earthquake-generated tsunamis is relatively low for present events, but increases significantly with higher sea level conditions. The probabilistic approach allowed us to undertake a comparison with an existing storm surge hazard assessment. Interestingly, the exposure to all the simulated tsunamis is significantly lower than that for the 1:100 storm surge scenarios, under the same initial sea level conditions. The results have significant implications for multi-risk and emergency management in Sydney.

  14. Multi-order nonlinear diffraction in second harmonic generation

    DEFF Research Database (Denmark)

    Saltiel, S. M.; Neshev, D.; Krolikowski, Wieslaw

    We analyze the emission patterns in the process of second harmonic (SH) generation in χ(2) nonlinear gratings and identify for the first time, to the best of our knowledge, the evidence of Raman-Nath type nonlinear diffraction in frequency doubling processes.......We analyze the emission patterns in the process of second harmonic (SH) generation in χ(2) nonlinear gratings and identify for the first time, to the best of our knowledge, the evidence of Raman-Nath type nonlinear diffraction in frequency doubling processes....

  15. Electrical conduction of a XLPE nanocomposite

    Science.gov (United States)

    Park, Yong-Jun; Sim, Jae-Yong; Lim, Kee-Joe; Nam, Jin-Ho; Park, Wan-Gi

    2014-07-01

    The resistivity, breakdown strength, and formation of space charges are very important factors for insulation design of HVDC cable. It is known that a nano-sized metal-oxide inorganic filler reduces the formation of space charges in the polymer nanocomposite. Electrical conduction of cross-linked polyethylene(XLPE) nanocomposite insulating material is investigated in this paper. The conduction currents of two kinds of XLPE nanocomposites and XLPE without nano-filler were measured at temperature of 303 ~ 363 K under the applied electric fields of 10 ~ 50 kV/mm. The current of the nanocomposite specimen is smaller than that of XLPE specimen without nano-filler. The conduction mechanism may be explained in terms of Schottky emission and multi-core model.

  16. Automatic Conversion of a Conceptual Model to a Standard Multi-view Web Services Definition

    Directory of Open Access Journals (Sweden)

    Anass Misbah

    2018-03-01

    Full Text Available Information systems are becoming more and more heterogeneous and here comes the need to have more generic transformation algorithms and more automatic generation Meta rules. In fact, the large number of terminals, devices, operating systems, platforms and environments require a high level of adaptation. Therefore, it is becoming more and more difficult to validate, generate and implement manually models, designs and codes.Web services are one of the technologies that are used massively nowadays; hence, it is considered as one of technologies that require the most automatic rules of validation and automation. Many previous works have dealt with Web services by proposing new concepts such as Multi-view Web services, standard WSDL implementation of Multi-view Web services and even further Generic Meta rules for automatic generation of Multi-view Web services.In this work we will propose a new way of generating Multi-view Web ser-vices, which is based on an engine algorithm that takes as input both an initial Conceptual Model and user’s matrix and then unroll a generic algorithm to gen-erate dynamically a validated set of points of view. This set of points of view will be transformed to a standard WSDL implementation of Multi-view Web services by means of the automatic transformation Meta rules.

  17. Design of improved controller for thermoelectric generator used in distributed generation

    Energy Technology Data Exchange (ETDEWEB)

    Molina, M.G. [CONICET, Instituto de Energia Electrica, Universidad Nacional de San Juan, Av. Libertador San Martin Oeste, 1109, J5400ARL, San Juan (Argentina); Juanico, L.E. [CONICET, Centro Atomico Bariloche, 8400 Bariloche (Argentina); Rinalde, G.F.; Taglialavore, E.; Gortari, S. [Centro Atomico Bariloche, 8400 Bariloche (Argentina)

    2010-06-15

    This paper investigates the application of thermal generation based on solid-state devices such as thermoelectric generators (TEGs) as a novel technological alternative of distributed generation (DG). The full detailed modeling and the dynamic simulation of a three-phase grid-connected TEG used as a dispersed generator is studied. Moreover, a new control scheme of the TEG is proposed, which consists of a multi-level hierarchical structure and incorporates a maximum power point tracker (MPPT) for better use of the thermal resource. In addition, reactive power compensation of the electric grid is included, operating simultaneously and independently of the active power generation. Validation of models and control schemes is performed by using the MATLAB/Simulink environment. Moreover, a small-scale TEG experimental set-up was employed to demonstrate the accuracy of proposed models. (author)

  18. Multi-scaling of the dense plasma focus

    Science.gov (United States)

    Saw, S. H.; Lee, S.

    2015-03-01

    The dense plasma focus is a copious source of multi-radiations with many potential new applications of special interest such as in advanced SXR lithography, materials synthesizing and testing, medical isotopes and imaging. This paper reviews the series of numerical experiments conducted using the Lee model code to obtain the scaling laws of the multi-radiations.

  19. Multi-emotion detection in user-generated reviews

    NARCIS (Netherlands)

    Buitinck, L.; van Amerongen, J.; Tan, E.; de Rijke, M.; Hanbury, A.; Kazai, G.; Rauber, A.; Fuhr, N.

    2015-01-01

    Expressions of emotion abound in user-generated content, whether it be in blogs, reviews, or on social media. Much work has been devoted to detecting and classifying these emotions, but little of it has acknowledged the fact that emotionally charged text may express multiple emotions at the same

  20. Multi-objective optimization of coal-fired power plants using differential evolution

    International Nuclear Information System (INIS)

    Wang, Ligang; Yang, Yongping; Dong, Changqing; Morosuk, Tatiana; Tsatsaronis, George

    2014-01-01

    Highlights: • Multi-objective optimization of large-scale coal-fired power plants using differential evolution. • A newly-proposed algorithm for searching the fronts of decision space in a single run. • A reduction of cost of electricity by 2–4% with an optimal efficiency increase up to 2% points. • The uncertainty comes mainly from temperature- and reheat-related cost factors of steam generator. • An exergoeconomic analysis and comparison between optimal designs and one real industrial design. - Abstract: The design trade-offs between thermodynamics and economics for thermal systems can be studied with the aid of multi-objective optimization techniques. The investment costs usually increase with increasing thermodynamic performance of a system. In this paper, an enhanced differential evolution with diversity-preserving and density-adjusting mechanisms, and a newly-proposed algorithm for searching the decision space frontier in a single run were used, to conduct the multi-objective optimization of large-scale, supercritical coal-fired plants. The uncertainties associated with cost functions were discussed by analyzing the sensitivity of the decision space frontier to some significant parameters involved in cost functions. Comparisons made with the aid of an exergoeconomic analysis between the cost minimum designs and a real industrial design demonstrated how the plant improvement was achieved. It is concluded that the cost of electricity could be reduced by a 2–4%, whereas the efficiency could be increased by up to two percentage points. The largest uncertainty is introduced by the temperature-related and reheat-related cost coefficients of the steam generator. More reliable data on the price prediction of future advanced materials should be used to obtain more accurate fronts of the objective space