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Sample records for delayed preputial separation

  1. Preputial retraction in children

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    Agarwal Abhinav

    2005-01-01

    Full Text Available OBJECTIVE: The aim of the study was to assess preputial retractability in children at various ages. MATERIALS AND METHODS: Nine hundred and sixty boys attending the hospital were included in the study. Children with hypospadias or history of preputial manipulation were excluded. Preputial anatomy was studied and subjects were classified into five groups as described by Kayaba et al . RESULTS: The prepuce could not be retracted at all so as to make even the external urethral meatus visible in 61.4% children aged 0-6 months while this decreased to only 0.9% in children aged 10-12 years. At the other end of the spectrum, while prepuce could not be fully retracted in any child below 6 months, it could be done in about 60% in the age group of 10-12 years. CONCLUSION Preputial nonseparation is the major cause of preputial nonretraction in the pediatric age group. Prepuce spontaneously separates from the glans as age increases and true phimosis is rare in children. Surgical intervention should be avoided for nonseparation of prepuce.

  2. Delayed umbilical cord separation in alloimmune neutropenia.

    OpenAIRE

    Kemp, A S; Lubitz, L

    1993-01-01

    Delayed umbilical cord separation in association with neonatal alloimmune neutropenia is reported. Delayed umbilical cord separation has been described in association with defects in neutrophil function. The present case indicates that deficiency in neutrophil number should also be considered as a cause of delayed cord separation.

  3. DELAYED PREPUTIAL SEPARATION (PPS) AND SP22 MEASUREMENT IN RATS ADMINISTERED BROMOCHLOROACETIC ACID (BCA) IN DRINKING WATER

    Science.gov (United States)

    Reproductive effects of BCA were determined in a dose range finding study (DRFS) and definitive two-generational study. Adult male and female CD� (SD) rats were administered BCA in drinking water for two weeks in the DRFS (10/sex/group) and ten weeks in the definitive study (25/s...

  4. Preputial calculus in a neurologically-impaired child.

    Science.gov (United States)

    Spataru, R I; Iozsa, D A; Ivanov, M

    2015-02-01

    Preputial calculi are rarely encountered in childhood. A 5-year-old boy with symptoms of chronic balanoposthitis. A preputial stone was documented and removed at circumcision. Uneventful postoperative recovery. In children, association between phimosis and neurologic impairment represent predisposing condition for preputial stone formation.

  5. A rare case of preputial calculi in a child with balanitis xerotica obliterans: A short communication

    Directory of Open Access Journals (Sweden)

    G.A. Kekre

    2016-09-01

    Full Text Available Preputial stones are the rarest form of urolithiasis in pediatric patients with only a few cases reported in the literature. Following, we present the case of an 11-year-old boy who developed preputial stones.

  6. A rare case of preputial calculi in a child with balanitis xerotica obliterans: A short communication

    OpenAIRE

    2016-01-01

    Preputial stones are the rarest form of urolithiasis in pediatric patients with only a few cases reported in the literature. Following, we present the case of an 11-year-old boy who developed preputial stones.

  7. Dorsal inlay inner preputial graft for primary hypospadias repair

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    Rajendra B. Nerli

    2014-01-01

    Full Text Available Background: The most commonly performed operation to repair distal hypospadias is the Tubularised incised plate (TIP repair. The key step is midline incision of the urethral plate, which widens a narrow plate and converts a flat into a deep plate groove, ensuring a vertical, slit neomeatus and a normal-calibre neourethra. At times in cases of proximal hypospadias, the urethral plate is very narrow and needs to be augmented or substituted for further tubularisation. We report our experience with primary single stage dorsal inlay urethroplasty using preputial skin grafts. Patients and Methods: Children with proximal hypospadias with a narrow urethral plate formed the study group. Children needing transection of the urethral plate, having undergone circumcision/hypospadias repair previously or having an inadequate prepuce was excluded. Results: Twelve children with a mean age of 48.83 months underwent primary dorsal inlay preputial graft urethroplasty for proximal hypospadias with a very narrow urethral plate. At an average follow-up of 42.16 months, 2 (16.66% children had a breakdown of ventral shaft skin. None of the children had meatal stenosis, and none of these 12 children developed urethrocutaneous fistula. Conclusion: Primary dorsal inlay inner preputial graft urethroplasty successfully fulfills all traditional hypospadias repair criteria. It offers a viable, safe, rapid and easy option in the management of proximal hypospadias with a narrow urethral plate.

  8. Delayed neutron studies of separated isotopes of Br, Rb, I, and Cs

    CERN Document Server

    Reeder, R L; Wright, J F

    1976-01-01

    Discusses delayed neutron studies of separated isotopes of Br, Rb, I, and Cs are currently in progress at the Spectrometer for On-Line Analysis of Radionuclides (SOLAR) facility operated by Battelle, Pacific Northwest Laboratories. (2 refs).

  9. Time-delayed beam splitting with energy separation of x-ray channels

    CERN Document Server

    Stetsko, Yuri P; Stephenson, G Brian

    2013-01-01

    We introduce a time-delayed beam splitting method based on the energy separation of x-ray photon beams. It is implemented and theoretically substantiated on an example of an x-ray optical scheme similar to that of the classical Michelson interferometer. The splitter/mixer uses Bragg-case diffraction from a thin diamond crystal. Another two diamond crystals are used as back-reflectors. For energy separation the back-reflectors are set at slightly different temperatures and angular deviations from exact backscattering. Because of energy separation and a minimal number (three) of optical elements, the split-delay line has high efficiency and is simple to operate. Due to the high transparency of diamond crystal, the split-delay line can be used in a beam sharing mode at x-ray free-electron laser facilities. The delay line can be made more compact by adding a fourth crystal.

  10. Impact of Pilot Delay and Non-Responsiveness on the Safety Performance of Airborne Separation

    Science.gov (United States)

    Consiglio, Maria; Hoadley, Sherwood; Wing, David; Baxley, Brian; Allen, Bonnie Danette

    2008-01-01

    Assessing the safety effects of prediction errors and uncertainty on automationsupported functions in the Next Generation Air Transportation System concept of operations is of foremost importance, particularly safety critical functions such as separation that involve human decision-making. Both ground-based and airborne, the automation of separation functions must be designed to account for, and mitigate the impact of, information uncertainty and varying human response. This paper describes an experiment that addresses the potential impact of operator delay when interacting with separation support systems. In this study, we evaluated an airborne separation capability operated by a simulated pilot. The experimental runs are part of the Safety Performance of Airborne Separation (SPAS) experiment suite that examines the safety implications of prediction errors and system uncertainties on airborne separation assistance systems. Pilot actions required by the airborne separation automation to resolve traffic conflicts were delayed within a wide range, varying from five to 240 seconds while a percentage of randomly selected pilots were programmed to completely miss the conflict alerts and therefore take no action. Results indicate that the strategicAirborne Separation Assistance System (ASAS) functions exercised in the experiment can sustain pilot response delays of up to 90 seconds and more, depending on the traffic density. However, when pilots or operators fail to respond to conflict alerts the safety effects are substantial, particularly at higher traffic densities.

  11. Time-delayed beam splitting with energy separation of x-ray channels

    Energy Technology Data Exchange (ETDEWEB)

    Stetsko, Yuri P.; Shvyd' ko, Yuri V.; Brian Stephenson, G. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2013-10-21

    We introduce a time-delayed beam splitting method based on the energy separation of x-ray photon beams. It is implemented and theoretically substantiated on an example of an x-ray optical scheme similar to that of the classical Michelson interferometer. The splitter/mixer uses Bragg-case diffraction from a thin diamond crystal. Another two diamond crystals are used as back-reflectors. Because of energy separation and a minimal number (three) of optical elements, the split-delay line has high efficiency and is simple to operate. Due to the high transparency of diamond crystal, the split-delay line can be used in a beam sharing mode at x-ray free-electron laser facilities.

  12. Collection of preputial material by scraping and aspiration for the diagnosis of Tritrichomonas foetus in bulls

    Directory of Open Access Journals (Sweden)

    P.C. Irons

    2002-07-01

    Full Text Available Two trials were carried out to assess the diagnostic sensitivity and practicability of preputial scraping as a method of collecting preputial material from bulls infected with Tritrichomonas foetus. In the 1st trial, preputial material was collected by simultaneous scraping and aspiration from 3 infected and 1 uninfected bull 10 times over a 5-week period. In the 2nd trial, samples from 5 infected bulls were collected by both sheath washing and scraping on 6 occasions, while 8 uninfected animals were sampled 3 times. Samples were cultured using a modified Trichomonas culture medium (Oxoid. In the first trial, 29 of 30 samples from infected bulls were found to be positive. In the second trial, 83 % of samples collected by both methods tested positive. In neither trial were any samples from the control bulls found to be positive. Scraping was found to be quick and safe, and offered advantages over preputial washing in that urine contamination was easily avoided, samples were smaller and more concentrated and contamination was reduced. It may, however, be subject to greater operator variability than sheath washing. It is concluded that preputial scraping is as effective as washing and represents a suitable alternative for the collection of material for direct examination and culture of Tritrichomonas foetus.

  13. Collection of preputial material by scraping and aspiration for the diagnosis of Tritrichomonas foetus in bulls.

    Science.gov (United States)

    Irons, P C; Henton, M M; Bertschinger, H J

    2002-06-01

    Two trials were carried out to assess the diagnostic sensitivity and practicability of preputial scraping as a method of collecting preputial material from bulls infected with Tritrichomonas foetus. In the 1st trial, preputial material was collected by simultaneous scraping and aspiration from 3 infected and 1 uninfected bull 10 times over a 5-week period. In the 2nd trial, samples from 5 infected bulls were collected by both sheath washing and scraping on 6 occasions, while 8 uninfected animals were sampled 3 times. Samples were cultured using a modified Trichomonas culture medium (Oxoid). In the first trial, 29 of 30 samples from infected bulls were found to be positive. In the second trial, 83 % of samples collected by both methods tested positive. In neither trial were any samples from the control bulls found to be positive. Scraping was found to be quick and safe, and offered advantages over preputial washing in that urine contamination was easily avoided, samples were smaller and more concentrated and contamination was reduced. It may, however, be subject to greater operator variability than sheath washing. It is concluded that preputial scraping is as effective as washing and represents a suitable alternative for the collection of material for direct examination and culture of Tritrichomonas foetus.

  14. Surgical Management of Penile and Preputial Neoplasms in Equine with Special Reference to Partial Phallectomy

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    Awad Rizk

    2013-01-01

    Full Text Available Penile and preputial neoplasia in horses occurs infrequently and represents diagnostic and therapeutic challenges. The present study was carried out on a total number of 21 equids (14 stallions and 7 donkeys suffered from different penile and preputial neoplasia. Diagnosis of neoplasms was based up on history of the case, clinical examination as well as histopathological evaluation. Animals with penile and preputial neoplasms were underwent local excision and partial phallectomy with a slightly modified version of the techniques described by William’s. The diagnosed neoplasms were penile and preputial squamous cell carcinomas (SCCs; ; sarcoid (; a-fibrosarcoma; and a melanoma. Local excision was curative in all cases except 5 stallions with SCCs. These stallions had extensive damage of the glans penis, free part of the penis and the inner lamina of the internal fold of the prepuce, and they underwent a partial phallectomy with successful outcome. Follow-up information was obtained by visit and telephone inquiries. In conclusion, penile and preputial neoplasms are commonly encountered in elderly male horses and SCCs are the most common type affecting male external genitalia. Partial phallectomy is effective for management of equine neoplasia if they are confined to the glans and body of the penis and there is no proximal spread or involvement to regional lymph nodes.

  15. Prepuce and partial penile amputation for treatment of preputial gland neoplasia in two ferrets.

    Science.gov (United States)

    van Zeeland, Y R A; Lennox, A; Quinton, J F; Schoemaker, N J

    2014-11-01

    Preputial tumours in ferrets are frequently malignant and therefore warrant prompt investigation. As many cases do not respond favourably to surgery, even in combination with radiation therapy, wide surgical resection has been recommended. Such a procedure may necessitate partial or total penile resection but outcomes have thus far not been well described. The current case series describes two ferrets in which surgical resection, including penile amputation, was performed using 10 and 5 mm margins, respectively. In the first case, no recurrence of preputial gland adenocarcinoma was noted for 32 months postsurgery, whereas multiple attempts at surgery and radiation therapy were unsuccessful in the second. These cases suggest that margins of at least 1 cm may help achieve a better outcome. Penile amputation for the treatment of preputial tumours appears to be well tolerated by ferrets, as demonstrated by these cases.

  16. Gamma/neutron competition above the neutron separation energy in delayed neutron emitters

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    Valencia E.

    2014-03-01

    Full Text Available To study the β-decay properties of some well known delayed neutron emitters an experiment was performed in 2009 at the IGISOL facility (University of Jyväskylä in Finland using Total Absorption γ-ray Spectroscopy (TAGS technique. The aim of these measurements is to obtain the full β-strength distribution below the neutron separation energy (Sn and the γ/neutron competition above. This information is a key parameter in nuclear technology applications as well as in nuclear astrophysics and nuclear structure. Preliminary results of the analysis show a significant γ-branching ratio above Sn.

  17. Monte Carlo Analysis of Airport Throughput and Traffic Delays Using Self Separation Procedures

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    Consiglio, Maria C.; Sturdy, James L.

    2006-01-01

    This paper presents the results of three simulation studies of throughput and delay times of arrival and departure operations performed at non-towered, non-radar airports using self-separation procedures. The studies were conducted as part of the validation process of the Small Aircraft Transportation Systems Higher Volume Operations (SATS HVO) concept and include an analysis of the predicted airport capacity using with different traffic conditions and system constraints under increasing levels of demand. Results show that SATS HVO procedures can dramatically increase capacity at non-towered, non-radar airports and that the concept offers the potential for increasing capacity of the overall air transportation system.

  18. Prepuce and partial penile amputation for treatment of preputial gland neoplasia in two ferrets

    NARCIS (Netherlands)

    van Zeeland, Yvonne; Lennox, Angela; Quinton, Jean-François; Schoemaker, Nico

    2014-01-01

    Preputial tumours in ferrets are frequently malignant and therefore warrant prompt investigation. As many cases do not respond favourably to surgery, even in combination with radiation therapy, wide surgical resection has been recommended. Such a procedure may necessitate partial or total penile res

  19. A rare case of preputial calculi in a child with balanitis xerotica ...

    African Journals Online (AJOL)

    G.A. Kekre

    2016-07-26

    Jul 26, 2016 ... Department of Pediatric Surgery, LTMGH, Mumbai, India. Received 4 ... Following, we present the case of an 11-year-old boy who developed preputial stones. © 2016 Pan ... Pelvic X-ray showed radio-opaque lesions in the.

  20. Effect of preputial washing on bacterial load and preservability of semen in Murrah buffalo bulls

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    G. S. Meena

    2015-06-01

    Full Text Available Aim: To study the effect of preputial washing on bacterial load, preservability and semen quality in Murrah buffalo bulls Materials and Methods: A total of 36 collections of three Murrah buffalo bulls maintained at Artificial Breeding Research Centre, ICAR-National Dairy Research Institute, Karnal, were collected at weekly intervals from each bull without preputial washing and latter ejaculates from same bull with preputial washing by infusing normal saline (0.85%, KMnO4 (0.02% and savlon (2.0% to first, second and third bull, respectively. The microbial load and semen quality were evaluated during different hours of storage at refrigerated temperature (0, 24 and 48 h and after thrawing of cryopreserved (at −196°C semen. Results: The results of preservation of semen at refrigerated temperature showed that bacterial load was markedly lower in ejaculates of bulls subjected to preputial washing. Semen preserved at refrigerator temperature and cryopreserved, the effect of washing solution was significant for individual motility (IM, non-eosiniphilic count, hypo-osmotic swelling reactivity (HOST, total plate count (TPC and acrosome integrity. KMnO4 was found to be the best in lowering bacterial load, sperm abnormalities and in improving semen quality such as motility, non-eosinophilic count, HOST and acrosome integrity even up to 48 h of preservation and cryopreserved semen. Effect of duration of preservation and stage of cryopreservation was also significant for IM, non-eosiniphilic count, HOST, sperm abnormalities and acrosome integrity. Conclusion: Overall the results suggested that preputial washing with KMnO4 solution improved the semen quality and reduced microbial load of Murrah buffalo bull’s semen preserved at refrigerated temperature and cryopreservation.

  1. Use of preputial skin for coverage of post-burn contractures of fingers in children

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    Mohammed I Zaroo

    2011-01-01

    Full Text Available Objective: Hand burns are common injuries. Children frequently sustain burn injuries, especially to their hands. Contractures are a common sequel of severe burns around joints. The prepuce, or foreskin, has been used as a skin graft for a number of indications. We conducted this study to evaluate the feasibility of utilising the preputial skin for the management of post-burn contractures of fingers in uncircumcised male children. Materials and Methods: Preputial skin was used for the coverage of released contractures of fingers in 12 patients aged 2-6 years. The aetiology of burns was "Kangri" burn in eight patients and scalding in four patients. Six patients had contracture in two fingers, four patients in one finger, and two patients had contractures in three fingers. Results: None of the patients had graft loss, and all the wounds healed within 2 weeks. All patients had complete release of contractures without any recurrence. Hyperpigmentation of the grafts was observed over a period of time, which was well accepted by the parents. Conclusions: Preputial skin can be used successfully for male children with mild-to-moderate contractures of 2-3 fingers for restoration of the hand function, minimal donor site morbidity.

  2. Outcome of a standardized technique of preputial preservation surgery for phimosis: A single institutional experience

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    Kamalesh Pal

    2014-01-01

    Full Text Available Introduction: Pathological phimosis or preputial stenosis is a distressing problem in children leading to recurrent balanoposthitis, ballooning of prepuce, and rarely back pressure changes in the urinary tract. Circumcision has been the standard of care for such situations, although recently, various alternatives to circumcision have been reported in the literature. Most of these techniques are often complex and are met with poor acceptance. Moreover, besides personal preferences (in Hindus, advantages of preputial preservation is increasingly being realized recently. Materials and Methods: A prospective study was carried out in which a simple standardized technique of preputioplasty (dorsal slit was used in 40 pediatric preputial stenosis cases. The outcome of this procedure including cosmesis and parental satisfaction was evaluated. Results: The average duration of this procedure was from 10 to 25 min with no intraoperative complications. The cosmetic outcome was good in 62.5%, satisfactory in 30%, and poor in 7.5% of cases. All of the boys had retractable prepuce with no functional problems. There was 100% parental satisfaction. None of the patients required a redo procedure or circumcision. Conclusion: A dorsal slit of adequate length i.e.; 1/3 rd the length from the corona to the tip leads to a satisfactory cosmetic outcome in more than 92% of cases. Preputioplasty is a safe and simple alternative to more radical procedure of circumcision.

  3. A Novel Strategy for Simulating the Main Fractionator of Delayed Cokers by Separating the De-superheating Process

    Institute of Scientific and Technical Information of China (English)

    LEI Yang; ZHANG Bingjian; HOU Xiaoqiong; CHEN Qinglin

    2013-01-01

    Delayed coking is an important process in refinery to convert heavy residue oils from crude distillation units (CDUs) and fluid catalytic cracking units (FCCUs) into dry gas,liquefied petroleum gas (LPG),gasoline,diesel,gas oils and cokes.The main fractionator,separating superheating reaction vapors from the coke drums into lighter oil products,involves a de-superheating section and a rectifying section,and couldn't be simulated as a whole column directly because of non-equilibrium in the de-superheating section.It is very important to correctly simulate the main fractionator for operational parameter and energy-use optimization of delayed cokers.This paper discusses the principle of de-superheating processes,and then proposes a new simulation strategy.Some key issues such as composition prediction of the reaction vapors,selection of thermodynamic methods,estimation of tray efficiency,etc.are discussed.The proposed simulation approach is applied to two industrial delayed cokers with typical technological processes in a Chinese refinery by using PRO/II.The simulation results obtained are well consistent with the actual operation data,which indicates that the presented approach is suitable to simulate the main fractionators of delayed cokers or other distillation columns consisting of de-superheating sections and rectifying sections.

  4. Oestrogen receptor expression and neuronal nitric oxide synthase in the clitoris and preputial gland structures of mice.

    Science.gov (United States)

    Martin-Alguacil, Nieves; Schober, Justine; Kow, Lee-Ming; Pfaff, Donald

    2008-12-01

    To study the presence of oestrogen receptors (ER) and neuronal nitric oxide synthase (nNOS) in the mouse clitoris. A series of sections of the pelvic area, including the preputial glands and clitoris, of 10 mice were assessed by immunocytochemical studies specific for ER-alpha and -beta, and nNOS; selected sections were also stained with Masson's trichrome. ER alpha was detected in the epithelium of the gland of the clitoris, and in the glandular tissue, preputial and apocrine gland. ER alpha was detected in the nuclei of stromal cells around the cavernous tissue and near the epithelium of the clitoris. Cytoplasm ER alpha was detected in a few cells in an area ventral to the clitoral gland. There was also nuclear staining in the connective tissue cells surrounding the clitoris. Very light ER beta immunostaining was detected in the clitoris and in the tissue related to it. There were some cells with nuclear staining in the vessels of the cavernous tissue of the clitoris. nNOS immunostaining was detected in the clitoris, the preputial gland and the connective tissue. ER alpha and beta isoforms, and nNOS, are present in the clitoris and preputial glands of female mice in different cellular locations and with differing levels of receptivity. Functional studies would further elucidate the role of receptor functions and their relationship to the neuronal expression of NO.

  5. Efficient HOMO-LUMO separation by multiple resonance effect toward ultrapure blue thermally activated delayed fluorescence

    Science.gov (United States)

    Hatakeyama, Takuji; Ikuta, Toshiaki; Shiren, Kazushi; Nakajima, Kiichi; Nomura, Shintaro; Ni, Jingping

    2016-09-01

    Organic light-emitting diodes (OLEDs) play an important role in the new generation of flat-panel displays. Conventional OLEDs employing fluorescent materials together with triplet-triplet annihilation suffer from a relatively low internal quantum efficiency (IQE) of 62.5%. On the other hand, the IQE of OLEDs employing phosphorescent or thermally activated delayed fluorescence (TADF) materials can reach 100%. However, these materials exhibit very broad peaks with a full-width at half-maximum (FWHM) of 70-100 nm and cannot satisfy the color-purity requirements for displays. Therefore, the latest commercial OLED displays employ blue fluorescent materials with a relatively low IQE, and efficient blue emitters with a small FWHM are highly needed. In our manuscript, we present organic molecules that exhibit ultrapure blue fluorescence based on TADF. These molecules consist of three benzene rings connected by one boron and two nitrogen atoms, which establish a rigid polycyclic framework and significant localization of the highest occupied and lowest unoccupied molecular orbitals by a multiple resonance effect. An OLED device based on the new emitter exhibits ultrapure blue emission at 467 nm with an FWHM of 28 nm, Commission Internationale de l'Eclairage (CIE) coordinates of (0.12, 0.13), and an IQE of 100%, which represent record-setting performance for blue OLED devices.

  6. Two unusual cases of canine prostatitis: prostatitis in a castrated dog and preputial oedema in an intact male.

    Science.gov (United States)

    Duque, J; Macías-García, B; Tapia, P Ruíz; Ferrusola, C Ortega; Zaragoza, C; Barrera, R; Peña, Fj

    2010-10-01

    In this study, two unusual presentations of canine prostatitis are described; in the first case a 10-years-old neutered Boxer dog was presented to the Veterinary Teaching Hospital of the University of Extremadura with a complaint of anorexia, apathy and preputial discharge. In the second case, a local veterinarian referred an 8-years-old male Labrador to the Veterinary Teaching Hospital of the University of Extremadura. The dog had a history of pain in the caudal abdomen and preputial oedema. The final diagnosis in both cases was acute prostatitis. It is concluded that although canine prostatitis is a common disease, sometimes can have presentations that may differ from those classically described in the literature. © 2009 Blackwell Verlag GmbH.

  7. Does Preputial Reconstruction Increase Complication Rate Of Hypospadias Repair? 20-Year Systematic Review And Meta-analysis

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    Marco eCastagnetti

    2016-04-01

    Full Text Available Introduction: We performed a systematic review of the literature on preputial reconstruction (PR during hypospadias repair to determine the cumulative risk of preputial skin complications and the influence of PR on urethroplasty complications, namely fistula formation and overall reoperation rate of the repair.Material and Methods: A systematic search of the literature published after 06/1995 was performed in 06/2015 using the keyword hypospadias. Only studies on the outcome of PR in children, defined as dehiscence of the reconstructed prepuce or secondary phimosis needing circumcision, were selected. A meta-analysis of studies comparing PR vs. circumcision was performed for the outcomes hypospadias fistula formation and reoperation rate.Results: Twenty studies were identified. Nineteen reported the outcome of PR in 2115 patients. Overall, 95% (2016/2115 of patients undergoing PR had distal hypospadias. The cumulative rate of PR complications was 7.7% (163/2115 patients, including 5.7% (121/2115 patients preputial dehiscences and 1.5% (35/2117 reported patients secondary phimoses needing circumcision. A meta-analysis of 7 studies comparing patients undergoing PR vs. circumcision, showed no increased risk of urethral fistula formation associated with PR, Odds Ratio (Mantel-Haenszel, Fixed effect, 95% CI, 1.25 (0.80-1.97. Likewise, two studies comparing the overall reoperation rate did not show an increased risk of reoperation associated with PR, Odds Ratio (Mantel-Haenszel, Random effect, 95% CI, 1.27 (0.45-3.58. Conclusions: Preputial reconstruction carries an 8% risk of specific complications (dehiscence of reconstructed prepuce or secondary phimosis needing circumcision, but does not seem to increase the risk of urethroplasty complications, and the overall reoperation rate of hypospadias repair.

  8. Novel, species-typical esters from preputial glands of sympatric voles,Microtus montanus andM. pennsylvanicus.

    Science.gov (United States)

    Welsh, C J; Moore, R E; Bartelt, R J; Jackson, L L

    1988-01-01

    Olfactory signals may facilitate species recognition between the sympatric voles,Microtus montanus andM. pennsylvanicus. In an effort to isolate and identify compounds that might contribute to such a chemical communication system, the preputial glands of those voles have been examined. Morphological examinations show both vole species possess preputial glands; however, the glands ofM. montanus are much larger than those ofM. pennsylvanicus. Gas Chromatographie analysis revealed that the preputial glands ofM. montanus contain a series of species-typical lipids that are not found inM. pennsylvanicus. Using gas chromatography-mass spectrometry and nuclear magnetic resonance spectrometry, the species-typical lipids were identified as esters of branched, saturated, and unsaturated C5 and C4 alcohols and straight-chain C16, and "iso" branched C17 fatty acids. This is the first description of such esters from mammalian tissues. The results are discussed relative to the possibility that the species-typical esters act as species recognition cues for the sympatric voles.

  9. [Histologic study of stimulation of preputial glands in the mouse by androgens and inhibition by a detergent or zinc salts].

    Science.gov (United States)

    Marois, M; Rateau, J C; Elie, C

    1982-12-01

    Preputial glands are a kind of sebaceous glands ; they play a role in reproduction and sexual and social behavior by means of secreted pheromones. In this work, the authors compared the regression of these glands to that of seminal vesicles and investigated the stimulating potency of three androgens : testosterone, androstenedione, androsterone. These data demonstrate the sensitivity of preputial glands to all three androgens. Castration interrupted the secretory activity of the glandular cells of the acini. Four injections of 250 micrograms of testosterone, nine injections of 250 micrograms of androstenedione or androsterone to male mice castrated before puberty restored elaboration and holocrine secretion of sebum. The authors tested for a possible antagonistic action of two substances : a detergent, superinone (100 mg body weight) and zinc salts (10 mg body weight) associated to androgens. After treatment by superinone, histological analysis revealed glandular cell lysis. The action of zinc salts was less pronounced. Zinc acetate and sulfate seem to counter the elaboration of secretions without disrupting glandular structure. The mechanisms of action of their two substances are very probably different.

  10. Impact of Feedback Channel Delay over Joint User Scheduling Scheme and Separated Random User Scheduling Scheme in LTE-A System with Carrier Aggregation

    Directory of Open Access Journals (Sweden)

    Ahmed A. Ali

    2014-01-01

    Full Text Available In Long Term Evolution-Advanced (LTE-A, the signal quality in a wireless channel is estimated based on the channel quality measurements. The measurement results are used to select suitable modulation and coding scheme for each transmission, feedback, and processing delay, which can cause a mismatch between channel quality information (CQI and current channel state at the base station. However, prospect delays in the reception of such CQI may lead to a system performance degradation. This study analyzes the impact of CQI feedback delay on joint user scheduling (JUS scheme and separated random user scheduling (SRUS scheme in LTE-A system over carrier aggregation. The analysis will be compared with the system having delayed channel and perfect knowledge at different deployment scenario. We will study the throughput performance of both scheduling schemes with different deployment scenario, and then recommend the suitable deployment scenario to keep the desired QoS for a specific number of users. Results show that, in main beam directed at sector boundaries and diverse coverage, JUS scheme performs better than SRUS, which can justify the intensive use of user equipment power and extra control signaling overhead.

  11. Expression of p53, Ki67, EcPV2- and EcPV3 DNA, and viral genes in relation to metastasis and outcome in equine penile and preputial squamous cell carcinoma

    NARCIS (Netherlands)

    van den Top, J G B; Harkema, L; Lange, C; Ensink, J M; van de Lest, C H A; Barneveld, A; van Weeren, P R; Gröne, A; Martens, A

    2015-01-01

    REASONS FOR PERFORMING STUDY: Equine penile and preputial squamous cell carcinoma (SCC) is a potentially lethal disease of which little is known regarding the relationship between tumour characteristics and prognosis. OBJECTIVES: To assess the relationship between tumour differentiation grade (tumou

  12. On the Separability of Ill-Conditioned Convolutive Mixtures of Sources with Small Time Delay%微延迟病态卷积混叠盲源分离的可分性研究

    Institute of Scientific and Technical Information of China (English)

    刘海林; 谢胜利; 章晋龙

    2003-01-01

    The paper researches separability of blind sources of convolutive mixtures on the assumption that the num-ber of sensors is less than that of sources. When time delay is small, the necessary condition of separability of the ill-conditioned convolutive mixtures is given through transforming blind sources of convolutive mixtures into that of lin-ear mixtures.

  13. Reliable Prediction with Tuned Range-Separated Functionals of the Singlet-Triplet Gap in Organic Emitters for Thermally Activated Delayed Fluorescence (TADF)

    KAUST Repository

    Sun, Haitao

    2015-07-09

    The thermally activated delayed fluorescence (TADF) mechanism has recently attracted much interest in the field of organic light-emitting diodes (OLEDs). TADF relies on the presence of a very small energy gap between the lowest singlet and triplet excited states. Here, we demonstrate that time-dependent density functional theory (TD-DFT) in the Tamm-Dancoff Approximation can be very successful in the calculations of the lowest singlet and triplet excitation energies and the corresponding singlet-triplet gap when using nonempirically tuned range-separated functionals. Such functionals provide very good estimates in a series of 17 molecules used in TADF-based OLED devices, with mean absolute deviations of 0.15 eV for the vertical singlet excitation energies and 0.09 eV [0.07 eV] for the adiabatic [vertical] singlet-triplet energy gaps as well as low relative errors and high correlation coefficients compared to the corresponding experimental values. They significantly outperform conventional functionals, a feature which is rationalized on the basis of the amount of exact-exchange included and the delocalization error. The present work provides a reliable theoretical tool for the prediction and development of novel TADF-based materials with low singlet-triplet energetic splittings.

  14. Improvements to the on-line mass separator, RAMA, and the beta-delayed charged-particle emission of proton-rich sd shell nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Ognibene, Theodore Joseph [Lawrence Berkeley National Lab., CA (United States). Nuclear Science Div.

    1996-03-01

    To overcome the extreme difficulties encountered in the experimental decay studies of proton drip line nuclei, several techniques have been utilized, including a helium-jet transport system, particle identification detectors and mass separation. Improvements to the ion source/extraction region of the He-jet coupled on-line Recoil Atom Mass Analyzer (RAMA) and its target/ion source coupling resulted in significant increases in RAMA efficiencies and its mass resolution, as well as reductions in the overall transit time. At the 88-Inch Cyclotron at LBNL, the decays of 31Cl, 27P and 28P, with half-lives of 150 msec, 260 msec and 270.3 msec, respectively, were examined using a he-jet and low-energy gas ΔE-gas ΔE-silicon E detector telescopes. Total beta-delayed proton branches of 0.3% and 0.07% in 31Cl and 27P, respectively, were estimated. Several proton peaks that had been previously assigned to the decay of 31Cl were shown to be from the decay of 25Si. In 27P, two proton groups at 459 ± 14 keV and 610 ± 11 keV, with intensities of 7 ± 3% and 92 ± 4% relative to the main (100%) group were discovered. The Gamow-Teller component of the preceding beta-decay of each observed proton transition was compared to results from shell model calculations. Finally, a new proton transition was identified, following the β-decay of 28P, at 1,444 ± 12 keV with a 1.7 ± 0.5% relative intensity to the 100% group. Using similar low-energy detector telescopes and the mass separator TISOL at TRIUMF, the 109 msec and 173 msec activities, 17Ne and 33Ar, were studied. A new proton group with energy 729 ± 15 keV was observed following the beta-decay of 17Ne. Several discrepancies between earlier works as to the energies, intensities and assignments of several proton transitions from 17Ne and 33Ar were resolved.

  15. Improvements to the on-line mass separator, RAMA, and the beta-delayed charged-particle emission of proton-rich sd shell nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Ognibene, T.J. [Lawrence Berkeley National Lab., CA (United States). Nuclear Science Div.

    1996-03-01

    To overcome the extreme difficulties encountered in the experimental decay studies of proton drip line nuclei, several techniques have been utilized, including a helium-jet transport system, particle identification detectors and mass separation. Improvements to the ion source/extraction region of the He-jet coupled on-line Recoil Atom Mass Analyzer (RAMA) and its target/ion source coupling resulted in significant increases in RAMA efficiencies and its mass resolution, as well as reductions in the overall transit time. At the 88-Inch Cyclotron at LBNL, the decays of {sup 31}Cl, {sup 27}P and {sup 28}P, with half-lives of 150 msec, 260 msec and 270.3 msec, respectively, were examined using a he-jet and low-energy gas {Delta}E-gas {Delta}E-silicon E detector telescopes. Total beta-delayed proton branches of 0.3% and 0.07% in {sup 31}Cl and {sub 27}P, respectively, were estimated. Several proton peaks that had been previously assigned to the decay of {sup 31}Cl were shown to be from the decay of {sup 25}Si. In {sup 27}P, two proton groups at 459 {+-} 14 keV and 610 {+-} 11 keV, with intensities of 7 {+-} 3% and 92 {+-} 4% relative to the main (100%) group were discovered. The Gamow-Teller component of the preceding beta-decay of each observed proton transition was compared to results from shell model calculations. Finally, a new proton transition was identified, following the {beta}-decay of {sup 28}P, at 1,444 {+-} 12 keV with a 1.7 {+-} 0.5% relative intensity to the 100% group. Using similar low-energy detector telescopes and the mass separator TISOL at TRIUMF, the 109 msec and 173 msec activities, {sup 17}Ne and {sup 33}Ar, were studied. A new proton group with energy 729 {+-} 15 keV was observed following the beta-decay of {sup 17}Ne. Several discrepancies between earlier works as to the energies, intensities and assignments of several proton transitions from {sup 17}Ne and {sup 33}Ar were resolved.

  16. Evaluation of a monoclonal antibody-based enzyme-linked immunosorbent assay for detection of Campylobacter fetus in bovine preputial washing and vaginal mucus samples.

    Science.gov (United States)

    Brooks, B W; Devenish, J; Lutze-Wallace, C L; Milnes, D; Robertson, R H; Berlie-Surujballi, G

    2004-10-05

    A monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) was described and evaluated for use as a presumptive screening test for detection of Campylobacter fetus in bovine preputial washing and vaginal mucus samples. A total of 725 diagnostic samples collected in the field and submitted in Clark's transport enrichment medium (TEM) were analyzed. Cultural isolation of C. fetus was used as the standard for comparison. After incubation of the TEM vials for 4-5 days, fluid was removed for culture and ELISA testing. A sandwich ELISA format was used and the target antigen was C. fetus lipopolysaccharides (LPS). A rabbit anti-C. fetus polyclonal antiserum was used as the capture antibody. Murine monoclonal antibodies (MAbs) to C. fetus serotype A and B LPS core and O-polysaccharides and a goat anti-mouse horseradish peroxidase conjugate were used as detection antibodies. ELISA and culture results for the diagnostic samples were in complete agreement. Seven hundred and eight samples were negative by both tests. All 17 culture positive samples were positive by ELISA with a MAb to LPS core. The ELISA with MAbs to LPS O-polysaccharides detected all culture positive samples with the homologous C. fetus serotype. Sixty-six preputial wash samples from three known C. fetus culture positive bulls were also analyzed. Forty-nine of these samples were positive by both ELISA and culture, 16 were positive by ELISA only, and one was negative by both ELISA and culture. The results indicate that this ELISA is useful as a screening test for the detection of C. fetus in diagnostic samples.

  17. Measurement of insulin-like growth factor-1 and insulin-like growth factor binding protein-3 after delayed separation of whole blood samples.

    Science.gov (United States)

    Hartog, Hermien; van der Graaf, Winette T A; Wesseling, Jelle; van der Veer, Eveline; Boezen, H Marike

    2008-05-01

    Epidemiological studies benefit from unbiased blood specimens collected with minimal cost and effort of blood collection and storage. We evaluated the stability of IGF-1 and IGFBP-3 in whole blood samples stored at room temperature to justify delays in blood processing. Total IGF-1 and IGFBP-3 levels were measured in EDTA plasma (n=12), heparin plasma (n=12) and serum (n=10) samples of healthy volunteers after blood processing delays up till 14 days. Stability of measured IGF-1 and IGFBP-3 levels was tested by paired t-test and a linear mixed effect model. Longitudinal analysis showed that IGF-1 levels were not significantly affected by blood processing delays in EDTA tubes (p=0.18) and IGFBP-3 levels were marginally stable (p=0.06). In heparin plasma and serum, however, IGF-1 increased over time of delayed processing and IGFBP-3 levels tended to decrease (p<0.01). Total IGF-1 and IGFBP-3 levels are stable in whole blood collected in EDTA tubes at room temperature up till 7 days, allowing a delay in blood processing to reduce costs in large multi-center studies.

  18. Delayed Puberty

    DEFF Research Database (Denmark)

    Kolby, Nanna; Busch, Alexander Siegfried; Juul, Anders

    2017-01-01

    Delayed puberty can be a source of great concern and anxiety, although it usually is caused by a self-limiting variant of the normal physiological timing named constitutional delay of growth and puberty (CDGP). Delayed puberty can, however, also be the first presentation of a permanent condition ...... mineral density) and psychological (e.g., low self-esteem) and underline the importance of careful clinical assessment of the patients.......Delayed puberty can be a source of great concern and anxiety, although it usually is caused by a self-limiting variant of the normal physiological timing named constitutional delay of growth and puberty (CDGP). Delayed puberty can, however, also be the first presentation of a permanent condition...

  19. Delayed fission

    Energy Technology Data Exchange (ETDEWEB)

    Hatsukawa, Yuichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-07-01

    Delayed fission is a nuclear decay process that couples {beta} decay and fission. In the delayed fission process, a parent nucleus undergoes {beta} decay and thereby populates excited states in the daughter. If these states are of energies comparable to or greater than the fission barrier of the daughter, then fission may compete with other decay modes of the excited states in the daughter. In this paper, mechanism and some experiments of the delayed fission will be discussed. (author)

  20. An unusual localization: Preputial hemangioma

    Directory of Open Access Journals (Sweden)

    Cansu Unden Ozcan

    2015-09-01

    Full Text Available Hemangiomas are the most common tumor of infantile period and usually involved sites are head and neck (%50, followed by trunk and extremities. Hemangioma is rarely described in genitals. We report a 17-months-old patient with a hemangioma of the preputium penis. The tumor was completely removed surgically and histological examination revealed an infantile hemangioma.

  1. Time Delay of CGM Sensors

    Science.gov (United States)

    Schmelzeisen-Redeker, Günther; Schoemaker, Michael; Kirchsteiger, Harald; Freckmann, Guido; Heinemann, Lutz; del Re, Luigi

    2015-01-01

    Background: Continuous glucose monitoring (CGM) is a powerful tool to support the optimization of glucose control of patients with diabetes. However, CGM systems measure glucose in interstitial fluid but not in blood. Rapid changes in one compartment are not accompanied by similar changes in the other, but follow with some delay. Such time delays hamper detection of, for example, hypoglycemic events. Our aim is to discuss the causes and extent of time delays and approaches to compensate for these. Methods: CGM data were obtained in a clinical study with 37 patients with a prototype glucose sensor. The study was divided into 5 phases over 2 years. In all, 8 patients participated in 2 phases separated by 8 months. A total number of 108 CGM data sets including raw signals were used for data analysis and were processed by statistical methods to obtain estimates of the time delay. Results: Overall mean (SD) time delay of the raw signals with respect to blood glucose was 9.5 (3.7) min, median was 9 min (interquartile range 4 min). Analysis of time delays observed in the same patients separated by 8 months suggests a patient dependent delay. No significant correlation was observed between delay and anamnestic or anthropometric data. The use of a prediction algorithm reduced the delay by 4 minutes on average. Conclusions: Prediction algorithms should be used to provide real-time CGM readings more consistent with simultaneous measurements by SMBG. Patient specificity may play an important role in improving prediction quality. PMID:26243773

  2. Ablación del divertículo prepucial en el cerdo como profilaxis de la contaminación seminal (Ablation of the preputial divertículum in the pig like prevention of the seminal contamination

    Directory of Open Access Journals (Sweden)

    Domínguez Fernández de Tejerina, J.C.

    2011-02-01

    Full Text Available ResumenLa ablación del divertículo prepucial no constituye todavía una intervención quirúrgica de práctica frecuente, por lo que en el presente trabajo se exponen los resultados relacionados con la contaminación seminal así como la técnica quirúrgica empleada. Se trabajó con un grupo de veintidós verracos jóvenes comprendidos en la edad de 32 a 36 semanas, de ellos se seleccionaron cinco al azar para la toma de muestras del contenido diverticular y de semen para elestudio bacteriológico.SummaryThe ablation of the preputial divertículum doesn’t still constitute a surgical intervention of frequent practice. The present work related the results the seminal contamination is exposed as well as the surgical technique employee.

  3. Penile self-mutilation as an unusual sign of a separation-related problem in a crossbreed dog.

    Science.gov (United States)

    Ghaffari, M Selk; Khorami, N; Marjani, M; Aldavood, S J

    2007-11-01

    A two-year-old, male, crossbreed dog was presented for evaluation of licking, biting and severe self-mutilation of its penis, which resulted in ulcers and haemorrhagic preputial discharge. History revealed signs of separation anxiety such as active greeting behaviour, excessive vocalisation and intermittent episodes of licking of the penis when the dog was left alone. The owner reported that he had been hospitalised after a car accident, and he had no chance of seeing the dog. During that time, the behaviour progressed to frequent episodes of licking and biting of the penis. Three weeks of treatment with clomipramine in addition to the presence of the dog's brother, who was brought into the dog's living environment, appeared to produce a considerable degree of improvement. The purpose of this report is to contribute to an increased awareness within veterinary practice of unusual signs of separation anxiety such as penile self-mutilation.

  4. Inlay internal preputial graft urethroplasty for hypospadias repair%镶嵌式包皮内板尿道成形术治疗尿道下裂临床分析

    Institute of Scientific and Technical Information of China (English)

    刘毅东; 庄利恺; 叶惟靖; 吴旻; 陈方

    2015-01-01

    Objective Over the past two decades,Snodgrass tubularized incised plate (TIP) urethroplasty has become one of dominant operative techniques because of wide applications and excellent cosmetics.However,it has also many limitations.Our goal was to assess the effectiveness of inlay internal preputial graft for expanding the applications of TIP.Methods Between January 2009 and December 2013,a total of 508 primary distal cases underwent urethroplasty with standard TIP hypospadias repair (n =198),inlay buccal mucosa graft (n =150) and inlay internal preputial graft (n =160).The mean age was 1.6 (1-4) years.In inlay graft groups,buccal mucosa or internal preputial graft was inserted between mid-line split urethral plate.The clinical data were analyzed statistically by x2.P<0.05 was deemed significant.Results The average follow-up period was 18 (6-24) months.The incidence of urinary fistula was 3.0% (6/198) ; meatal stenosis 3.0% (6/198) in standard TIP group; 3.3%(5/150)and 2.7%(4/150)in inlay buccal mucosa graft group; 1.25%(2/160) and 4.4% (7/160)in inlay internal preputial graft group.Overall success rates were 93.9% (189/198),94.0% (141/150) and 92.5% (149/160) respectively.Compared to STIP group,inlay buccal mucosa graft and inlay internal preputial graft groups,surgery success rate and complication rate showed no statistically significant difference (P>0.05).Conclusions For patients with primary distal type of hypospadias,normal penile development and no obvious chordee,corrections may be made by skin degloving or tunica albuginea folding.Dorsal inlay graft urethroplasty is efficacious for hypospadias repair with a high success rate and excellent cosmetic outcomes.Furthermore inner prepuce may be easily obtained without extra damage.%目的 尿道板中央切开卷管尿道成形术(tubularized incised plate,TIP,又称Snodgrass术)近20年成为了尿道下裂的主流术式之一,随着其应用范围的扩大该手术的局限性也逐步显

  5. Delayed childbearing.

    Science.gov (United States)

    Francis, H H

    1985-06-01

    In many Western nations, including England and Wales, Sweden, and the US, there is a current trend towards delayed childbearing because of women's pursuit of a career, later marriage, a longer interval between marriage and the 1st birth, and the increasing number of divorcees having children in a 2nd marriage. Wives of men in social classes I and II in England and Wales are, on average, having their 1st child at 27.9 years, 1.6 years later than in 1973, and in social classes IV and V, 1.0 years later than in 1973, at a mean age of 23.7 years. Consequently, the total period fertility rate for British women aged 30-34 years, 35-39 years, and 40 and over increased by 4%, 2%, and 4%, respectively, between 1982-83, in contrast to reductions of 2% and 3%, respectively, in the 15-19 year and 20-24 year age groups, with the 25-29-year-olds remaining static. The average maternal mortality for all parties in England and Wales during 1976-78 was 106/million for adolescents, 70.4/million for 20-24 year-olds, and 1162/million for those aged 40 years and older. The specific obstetric and allied conditions which increase with age are the hypertensive diseases of pregnancy, hemorrhage, pulmonary embolism, abortion, cardiac disease, caesarean section, ruptured uterus, and amniotic fluid embolism. The Swedish Medical Birth Registry of all live births and perinatal deaths since 1973 has shown that the risk of late fetal death is significantly greater in women aged 30-39 years than in those of the same parity and gravidity aged 20-24 years. The risk of giving birth to low birth weight babies preterm and at term and of premature labor are similarly increased. The early neonatal death rate also was increased for primigravidas and nulliparas in the 30-39 year age group but not in parous women. This is, in part, due to the rise in incidence of fetal abnormalities with advancing maternal age because of chromosomal and nonchromosomal anomalies. These also appear to be the cause of the

  6. 袖状蒂岛状环形包皮瓣尿道成形术一期修复会阴型尿道下裂%One-stage urethroplasty with circumferential vascular pedicle preputial island flap for perineal hypospadias

    Institute of Scientific and Technical Information of China (English)

    朱再生; 吴汉; 李瑞阳; 汪定海

    2010-01-01

    Objective To report the treatment of perineal hypospadias with one-stage urethroplaty with circumferential vascular pedicle preputial island flap. Methods A circumferential incision was made proximal to the corona and the urethral plate to correct chordee. A U-shaped skin incision was then made surrounding the meatus, and extended to the dorsal prepuce and parallel to the first incision. The tissue between the prepuce and dartos was dissected on the dorsum of penis to fix the prepuce as a neourethra.After mobilizing the loop shaped skin flap through the button-hole of the pedicle, the internal and external sides of the loop were sutured to construct a new urethra, the catheter was removed 10-14 days (mean,12.8 days ) after operation. Results Since 1997, 22 patients with perineal hypospadias were treated.Primary healing was achieved in 18 cases(81.8% ). Fistula happened in 4 patients. Among them, one case with meatal stenosis was treated with dilatation. Another 3 patients were reoperated. The neourethral flap was 3.50-18.00 cm (mean, 9.43 cm) in length. All patients were followed up for more than 6 months. Good cosmetic appearance was achieved in 72. 7% (16/22) of the patients. Conclusions The circumferential vascular pedicle preputial island flap has advantages of good blood supply and autograft for new meatus, which allows the chordee correction and urethroplaty at one stage. It is a good method for the treatment of perineal hypospadias with severe chordee and penoscrotal transposition.%目的 探讨袖状蒂岛状环形包皮瓣尿道成形术一期修复会阴型尿道下裂的临床效果.方法 距冠状沟0.5 cm处环形切开包皮内板和尿道板,脱套以纠正阴茎下曲.沿尿道板两侧平行切开,近端绕尿道口后会合,呈U形,远端环绕包皮到背侧,使新尿道皮瓣呈环状.解剖供应皮瓣的深层皮下组织与阴茎皮肤,形成血管蒂.经纽扣样孔隙,转移环状皮瓣至腹侧.缝合岛状环形皮瓣的内、外缘,形

  7. LONGITUDINAL PREPUTIAL PEDICLED FLAP URETHROPLASTY FOR CHORDEE OF Donnahoo TYPE Ⅳ%纵行带蒂包皮瓣卷管尿道间置矫治先天性Donnahoo Ⅳ型阴茎下曲畸形

    Institute of Scientific and Technical Information of China (English)

    曾莉; 单伟; 袁淼; 黄桂珍; 黄鲁刚

    2012-01-01

    目的 探讨纵行带蒂包皮瓣卷管尿道间置矫治先天性DonnahooⅣ型阴茎下曲畸形的疗效.方法 1994年6月-2011年10月,采用纵行带蒂包皮瓣卷管尿道间置矫治先天性DonnahooⅣ型阴茎下曲畸形患者30例.年龄2~16岁,平均5.8岁.入院检查:阴茎头-舟状窝-尿道外口形态以及与邻近组织关系正常;阴茎长度2.5~6.8 cm,平均4.3 cm;弯曲角度35~70°,平均40.1°.初次手术27例,再次手术3例.皮瓣切取范围1.5 cm × 1.3 cm~4.0 cm×2.0 cm.结果 下曲畸形矫正后阴茎长度3.0~8.5 cm,平均6.6 cm;弯曲角度0~10°,平均1.2°.术后患者均获随访,随访时间6个月~12年,平均33个月.随访期间无阴茎下曲复发,阴茎头无刺痛、异物感等不适.4例(13.33%)拔除尿管后出现尿瘘,行尿瘘修补术后无复发;2例(6.67%)术后1个月出现尿线变细、排尿困难,给予尿道扩张后症状消失.其余患者均无明显并发症发生,尿流无散射,方向性好.6例随访至成年,诉性功能满意,无明显勃起障碍、勃起疼痛及性交困难等.结论 纵行带蒂包皮瓣卷管尿道间置矫治先天性DonnahooⅣ型阴茎下曲畸形具有操作简便、疗效确切等优点.%ObjectⅣe To investigate the effectⅣeness of longitudinal preputial pedicled flap urethroplasty for chordee of Donnahoo Ⅳ type. Methods Between June 1994 and October 2011, 30 patients with chordee (Donnahoo type Ⅳ) underwent longitudinal preputial pedicled flap urethroplasty. The patients' age ranged from 2 to 16 years (mean, 5.8 years). The morphology of the balanus-navicular fossa-external urethral orifice ranged normal; the penis length was 2.5-6.8 cm (mean, 4.3 cm); the penis bending angle was 35-70° (mean, 40.1°). Primary and secondary operation was 27 cases and 3 cases, respectⅣely. The size of flap ranged from 1.5 cm × 1.3 cm to 4.0 cm × 2.0 cm. Results After correction, the penis length was 3.0-8.5 cm (mean, 6.6 cm); the penis bending

  8. Separation Logic

    DEFF Research Database (Denmark)

    Reynolds, John C.

    2002-01-01

    expressions) for accessing and modifying shared structures, and for explicit allocation and deallocation of storage. Assertions are extended by introducing a "separating conjunction" that asserts that its sub-formulas hold for disjoint parts of the heap, and a closely related "separating implication". Coupled......, dynamically allocated arrays, and recursive procedures. We will also discuss promising future directions....

  9. Measuring and Modelling Delays in Robot Manipulators for Temporally Precise Control using Machine Learning.

    OpenAIRE

    Andersen, Thomas Timm; Amor, Heni Ben; Andersen, Nils Axel; Ravn, Ole

    2015-01-01

    Latencies and delays play an important role in temporally precise robot control. During dynamic tasks in particular, a robot has to account for inherent delays to reach manipulated objects in time. The different types of occurring delays are typically convoluted and thereby hard to measure and separate. In this paper, we present a data-driven methodology for separating and modelling inherent delays during robot control. We show how both actuation and response delays can be modelled using mode...

  10. IN VIVO AND IN VITRO ANTI-ANDROGENIC EFFECTS OF DE-71

    Science.gov (United States)

    Recently, we showed that the PBDE mixture, DE-71, delayed preputial separation (PPS) and suppressed the growth of androgen-dependent tissues in the Wistar rat following a peri-pubertal exposure. These effects occurred concurrently with hypothyroidism and suggested that in additi...

  11. CENTRIFUGAL SEPARATORS

    Science.gov (United States)

    Skarstrom, C.

    1959-03-10

    A centrifugal separator is described for separating gaseous mixtures where the temperature gradients both longitudinally and radially of the centrifuge may be controlled effectively to produce a maximum separation of the process gases flowing through. Tbe invention provides for the balancing of increases and decreases in temperature in various zones of the centrifuge chamber as the result of compression and expansions respectively, of process gases and may be employed effectively both to neutralize harmful temperature gradients and to utilize beneficial temperaturc gradients within the centrifuge.

  12. The Right Delay

    NARCIS (Netherlands)

    Datadien, A.H.R.; Haselager, W.F.G.; Sprinkhuizen-Kuyper, I.G.

    2011-01-01

    Axonal conduction delays should not be ignored in simulations of spiking neural networks. Here it is shown that by using axonal conduction delays, neurons can display sensitivity to a specific spatio-temporal spike pattern. By using delays that complement the firing times in a pattern, spikes can ar

  13. Measuring and Modelling Delays in Robot Manipulators for Temporally Precise Control using Machine Learning

    DEFF Research Database (Denmark)

    Andersen, Thomas Timm; Amor, Heni Ben; Andersen, Nils Axel

    2015-01-01

    and separate. In this paper, we present a data-driven methodology for separating and modelling inherent delays during robot control. We show how both actuation and response delays can be modelled using modern machine learning methods. The resulting models can be used to predict the delays as well...

  14. Stability interval for time-varying delay systems

    OpenAIRE

    Ariba, Yassine; Gouaisbaut, F.; Johansson, Karl Henrik

    2010-01-01

    We investigate the stability analysis of linear time-delay systems. The time-delay is assumed to be a time-varying continuous function belonging to an interval (possibly excluding zero) with a bound on its derivative. To this end, we propose to use the quadratic separation framework to assess the intervals on the delay that preserves the stability. Nevertheless, to take the time-varying nature of the delay into account, the quadratic separation principle has to be extended to cope with the ge...

  15. An Analytical Delay Model

    Institute of Scientific and Technical Information of China (English)

    MIN Yinghua; LI Zhongcheng

    1999-01-01

    Delay consideration has been a majorissue in design and test of high performance digital circuits. Theassumption of input signal change occurring only when all internal nodesare stable restricts the increase of clock frequency. It is no longertrue for wave pipelining circuits. However, previous logical delaymodels are based on the assumption. In addition, the stable time of arobust delay test generally depends on the longest sensitizable pathdelay. Thus, a new delay model is desirable. This paper explores thenecessity first. Then, Boolean process to analytically describe thelogical and timing behavior of a digital circuit is reviewed. Theconcept of sensitization is redefined precisely in this paper. Based onthe new concept of sensitization, an analytical delay model isintroduced. As a result, many untestable delay faults under thelogical delay model can be tested if the output waveforms can be sampledat more time points. The longest sensitizable path length is computedfor circuit design and delay test.

  16. GPS Separator

    CERN Multimedia

    2016-01-01

    Footage of the 70 degree ISOLDE GPS separator magnet MAG70 as well as the switchyard for the Central Mass and GLM (GPS Low Mass) and GHM (GPS High Mass) beamlines in the GPS separator zone. In the GPS20 vacuum sector equipment such as the long GPS scanner 482 / 483 unit, faraday cup FC 490, vacuum valves and wiregrid piston WG210 and WG475 and radiation monitors can also be seen. Also the RILIS laser guidance and trajectory can be seen, the GPS main beamgate switch box and the actual GLM, GHM and Central Beamline beamgates in the beamlines as well as the first electrostatic quadrupoles for the GPS lines. Close up of the GHM deflector plates motor and connections and the inspection glass at the GHM side of the switchyard.

  17. HRS Separator

    CERN Multimedia

    2016-01-01

    Footage of the 90 and 60 degree ISOLDE HRS separator magnets in the HRS separator zone. In the two vacuum sectors HRS20 and HRS30 equipment such as the HRS slits SL240, the HRS faraday cup FC300 and wiregrid WG210 can be spotted. Vacuum valves, turbo pumps, beamlines, quadrupoles, water and compressed air connections, DC and signal cabling can be seen throughout the video. The HRS main and user beamgate in the beamline between MAG90 and MAG60 and its switchboxes as well as all vacuum bellows and flanges are shown. Instrumentation such as the HRS scanner unit 482 / 483, the HRS WG470 wiregrid and slits piston can be seen. The different quadrupoles and supports are shown as well as the RILIS guidance tubes and installation at the magnets and the different radiation monitors.

  18. Delayed emergence after anesthesia.

    Science.gov (United States)

    Tzabazis, Alexander; Miller, Christopher; Dobrow, Marc F; Zheng, Karl; Brock-Utne, John G

    2015-06-01

    In most instances, delayed emergence from anesthesia is attributed to residual anesthetic or analgesic medications. However, delayed emergence can be secondary to unusual causes and present diagnostic dilemmas. Data from clinical studies is scarce and most available published material is comprised of case reports. In this review, we summarize and discuss less common and difficult to diagnose reasons for delayed emergence and present cases from our own experience or reference published case reports/case series. The goal is to draw attention to less common reasons for delayed emergence, identify patient populations that are potentially at risk and to help anesthesiologists identifying a possible cause why their patient is slow to wake up.

  19. American Dream Delayed

    DEFF Research Database (Denmark)

    Khorunzhina, Natalia; Miller, Robert A.

    This paper investigates the delay in homeownership and a subsequent reduction in homeownership rate observed over the past decades. We focus on the delay in giving birth to children and increased labor market participation as contributing factors to homeownership dynamics for prime-age female hou...

  20. Numerical Analysis of Shock Induced Separation Delay by Air Humidity

    Institute of Scientific and Technical Information of China (English)

    Piotr DOERFFER; Slawomir DYKAS

    2005-01-01

    @@ In this paper numerical calculations of the dry and humid air flows in the nozzle are presented. The dry air flow (adiabatic flow) and the humid air flow (flow with homogeneous condensation, diabatic flow) are modeled with the use of Reynolds Averaged Navier-Stokes (RANS) equations. The comparison of these two types of flow is carried out. The influence of the air humidity on the shock wave location and its interaction with the boundary layer is examined. Obtained numerical results present a first numerical approach of the condensation and evaporation process in transonic flow of humid air. The phenomena considered here are very complex and complicated and need further in-depth numerical analysis.

  1. Numerical Bifurcation Analysis of Delayed Recycle Stream in a Continuously Stirred Tank Reactor

    Science.gov (United States)

    Gangadhar, Nalwala Rohitbabu; Balasubramanian, Periyasamy

    2010-10-01

    In this paper, we present the stability analysis of delay differential equations which arise as a result of transportation lag in the CSTR-mechanical separator recycle system. A first order irreversible elementary reaction is considered to model the system and is governed by the delay differential equations. The DDE-BIFTOOL software package is used to analyze the stability of the delay system. The present analysis reveals that the system exhibits delay independent stability for isothermal operation of the CSTR. In the absence of delay, the system is dynamically unstable for non-isothermal operation of the CSTR, and as a result of delay, the system exhibits delay dependent stability.

  2. commensurate point delays

    Directory of Open Access Journals (Sweden)

    M. de la Sen

    2005-01-01

    nominal controller is maintained. In the current approach, the finite spectrum assignment is only considered as a particular case of the designer's choice of a (delay-dependent arbitrary spectrum assignment objective.

  3. Time Delay Cosmography

    OpenAIRE

    Treu, Tommaso; Marshall, Philip J.

    2016-01-01

    Gravitational time delays, observed in strong lens systems where the variable background source is multiply-imaged by a massive galaxy in the foreground, provide direct measurements of cosmological distance that are very complementary to other cosmographic probes. The success of the technique depends on the availability and size of a suitable sample of lensed quasars or supernovae, precise measurements of the time delays, accurate modeling of the gravitational potential of the main deflector,...

  4. Coherence delay augmented laser beam homogenizer

    Science.gov (United States)

    Rasmussen, P.; Bernhardt, A.

    1993-06-29

    The geometrical restrictions on a laser beam homogenizer are relaxed by ug a coherence delay line to separate a coherent input beam into several components each having a path length difference equal to a multiple of the coherence length with respect to the other components. The components recombine incoherently at the output of the homogenizer, and the resultant beam has a more uniform spatial intensity suitable for microlithography and laser pantogography. Also disclosed is a variable aperture homogenizer, and a liquid filled homogenizer.

  5. Time Delay Cosmography

    CERN Document Server

    Treu, Tommaso

    2016-01-01

    Gravitational time delays, observed in strong lens systems where the variable background source is multiply-imaged by a massive galaxy in the foreground, provide direct measurements of cosmological distance that are very complementary to other cosmographic probes. The success of the technique depends on the availability and size of a suitable sample of lensed quasars or supernovae, precise measurements of the time delays, accurate modeling of the gravitational potential of the main deflector, and our ability to characterize the distribution of mass along the line of sight to the source. We review the progress made during the last 15 years, during which the first competitive cosmological inferences with time delays were made, and look ahead to the potential of significantly larger lens samples in the near future.

  6. Prediction of delayed subsidence

    Science.gov (United States)

    Burns, K.

    A predictive model of delayed subsidence is discussed. A numerical implementation is tested on one of the best-described study areas, Allegheny County in Pennsylvania. In planning insurance of restitution measures, a predictive model is of value in estimating the magnitude of the problem and the size of long-term budgetary commitments. Contrary to active subsidence, which occurs concurrently with mining operations, or is completed within a few days following coal extraction, delayed subsidence may take many years to appear at the surface after coal mines are abandoned. There are two principal morphological types of delayed subsidence: troughs, which are shallow depressions, and sinks, which are steep-sided crown pits. Both types are damaging to surface structures, and a variety of methods were introduced to deal with the problem, ranging from subsidence insurance to site restitution.

  7. Time delay cosmography

    Science.gov (United States)

    Treu, Tommaso; Marshall, Philip J.

    2016-07-01

    Gravitational time delays, observed in strong lens systems where the variable background source is multiply imaged by a massive galaxy in the foreground, provide direct measurements of cosmological distance that are very complementary to other cosmographic probes. The success of the technique depends on the availability and size of a suitable sample of lensed quasars or supernovae, precise measurements of the time delays, accurate modeling of the gravitational potential of the main deflector, and our ability to characterize the distribution of mass along the line of sight to the source. We review the progress made during the last 15 years, during which the first competitive cosmological inferences with time delays were made, and look ahead to the potential of significantly larger lens samples in the near future.

  8. Modelling the Probability Density Function of IPTV Traffic Packet Delay Variation

    Directory of Open Access Journals (Sweden)

    Michal Halas

    2012-01-01

    Full Text Available This article deals with modelling the Probability density function of IPTV traffic packet delay variation. The use of this modelling is in an efficient de-jitter buffer estimation. When an IP packet travels across a network, it experiences delay and its variation. This variation is caused by routing, queueing systems and other influences like the processing delay of the network nodes. When we try to separate these at least three types of delay variation, we need a way to measure these types separately. This work is aimed to the delay variation caused by queueing systems which has the main implications to the form of the Probability density function.

  9. Delayed Random Relays

    CERN Document Server

    Ohira, Toru

    2016-01-01

    We present here a system with collection of random walks relaying a signal in one dimension with a presence of a delay. We are interested in the time for a signal to travel from one end (start) to the other end (finish) of the lined group of random walkers. It is found that there is an optimal number of walkers for the signal to travel fastest if the delay is present. We discuss implications of this model and associated behaviors to physical and biological systems.

  10. Approximation of distributed delays

    CERN Document Server

    Lu, Hao; Eberard, Damien; Simon, Jean-Pierre

    2010-01-01

    We address in this paper the approximation problem of distributed delays. Such elements are convolution operators with kernel having bounded support, and appear in the control of time-delay systems. From the rich literature on this topic, we propose a general methodology to achieve such an approximation. For this, we enclose the approximation problem in the graph topology, and work with the norm defined over the convolution Banach algebra. The class of rational approximates is described, and a constructive approximation is proposed. Analysis in time and frequency domains is provided. This methodology is illustrated on the stabilization control problem, for which simulations results show the effectiveness of the proposed methodology.

  11. Delay Bounds for Multiclass FIFO

    OpenAIRE

    Jiang, Yuming; Misra, Vishal

    2016-01-01

    FIFO is perhaps the simplest scheduling discipline. For single-class FIFO, its delay guarantee performance has been extensively studied: The well-known results include a stochastic delay bound for $GI/GI/1$ by Kingman and a deterministic delay bound for $D/D/1$ by Cruz. However, for multiclass FIFO, few such results are available. To fill the gap, we prove delay bounds for multiclass FIFO in this work, considering both deterministic and stochastic cases. Specifically, delay bounds are present...

  12. Delayed breast implant reconstruction

    DEFF Research Database (Denmark)

    Hvilsom, Gitte B.; Hölmich, Lisbet R.; Steding-Jessen, Marianne;

    2012-01-01

    We evaluated the association between radiation therapy and severe capsular contracture or reoperation after 717 delayed breast implant reconstruction procedures (288 1- and 429 2-stage procedures) identified in the prospective database of the Danish Registry for Plastic Surgery of the Breast during...... reconstruction approaches other than implants should be seriously considered among women who have received radiation therapy....

  13. Delayed traumatic diaphragmatic hernia

    Science.gov (United States)

    Lu, Jing; Wang, Bo; Che, Xiangming; Li, Xuqi; Qiu, Guanglin; He, Shicai; Fan, Lin

    2016-01-01

    Abstract Background: Traumatic diaphragmatic hernias (TDHs) are sometimes difficult to identify at an early stage and can consequently result in diagnostic delays with life-threatening outcomes. It is the aim of this case study to highlight the difficulties encountered with the earlier detection of traumatic diaphragmatic hernias. Methods: Clinical data of patients who received treatment for delayed traumatic diaphragmatic hernias in registers of the First Affiliated Hospital of Xi’an Jiaotong University from 1998 to 2014 were analyzed retrospectively. Results: Six patients were included in this study. Left hemidiaphragm was affected in all of them. Most of the patients had a history of traffic accident and 1 a stab-penetrating injury. The interval from injury to developing symptoms ranged from 2 to 11 years (median 5 years). The hernial contents included the stomach, omentum, small intestine, and colon. Diaphragmatic injury was missed in all of them during the initial managements. All patients received operations once the diagnosis of delayed TDH was confirmed, and no postoperative mortality was detected. Conclusions: Delayed TDHs are not common, but can lead to serious consequences once occurred. Early detection of diaphragmatic injuries is crucial. Surgeons should maintain a high suspicion for injuries of the diaphragm in cases with abdominal or lower chest traumas, especially in the initial surgical explorations. We emphasize the need for radiographical follow-up to detect diaphragmatic injuries at an earlier stage. PMID:27512848

  14. 'No delays achiever'.

    Science.gov (United States)

    2007-05-01

    The latest version of the NHS Institute for Innovation and Improvement's 'no delays achiever', a web based tool created to help NHS organisations achieve the 18-week target for GP referrals to first treatment, is available at www.nodelaysachiever.nhs.uk.

  15. Permissible Delay in Payments

    Directory of Open Access Journals (Sweden)

    Yung-Fu Huang

    2007-01-01

    Full Text Available The main purpose of this paper wants to investigate the optimal retailer's lot-sizing policy with two warehouses under partially permissible delay in payments within the economic order quantity (EOQ framework. In this paper, we want to extend that fully permissible delay in payments to the supplier would offer the retailer partially permissible delay in payments. That is, the retailer must make a partial payment to the supplier when the order is received. Then the retailer must pay off the remaining balance at the end of the permissible delay period. In addition, we want to add the assumption that the retailer's storage space is limited. That is, the retailer will rent the warehouse to store these exceeding items when the order quantity is larger than retailer's storage space. Under these conditions, we model the retailer's inventory system as a cost minimization problem to determine the retailer's optimal cycle time and optimal order quantity. Three theorems are developed to efficiently determine the optimal replenishment policy for the retailer. Finally, numerical examples are given to illustrate these theorems and obtained a lot of managerial insights.

  16. Delayed fluorescence in photosynthesis.

    Science.gov (United States)

    Goltsev, Vasilij; Zaharieva, Ivelina; Chernev, Petko; Strasser, Reto J

    2009-01-01

    Photosynthesis is a very efficient photochemical process. Nevertheless, plants emit some of the absorbed energy as light quanta. This luminescence is emitted, predominantly, by excited chlorophyll a molecules in the light-harvesting antenna, associated with Photosystem II (PS II) reaction centers. The emission that occurs before the utilization of the excitation energy in the primary photochemical reaction is called prompt fluorescence. Light emission can also be observed from repopulated excited chlorophylls as a result of recombination of the charge pairs. In this case, some time-dependent redox reactions occur before the excitation of the chlorophyll. This delays the light emission and provides the name for this phenomenon-delayed fluorescence (DF), or delayed light emission (DLE). The DF intensity is a decreasing polyphasic function of the time after illumination, which reflects the kinetics of electron transport reactions both on the (electron) donor and the (electron) acceptor sides of PS II. Two main experimental approaches are used for DF measurements: (a) recording of the DF decay in the dark after a single turnover flash or after continuous light excitation and (b) recording of the DF intensity during light adaptation of the photosynthesizing samples (induction curves), following a period of darkness. In this paper we review historical data on DF research and recent advances in the understanding of the relation between the delayed fluorescence and specific reactions in PS II. An experimental method for simultaneous recording of the induction transients of prompt and delayed chlorophyll fluorescence and decay curves of DF in the millisecond time domain is discussed.

  17. Delay-independent stabilization for teleoperation with time varying delay

    OpenAIRE

    Fujita, Hiroyuki; Namerikawa, Toru

    2009-01-01

    This paper deals with the stability for nonlinear teleoperation with time varying communication delays. The proposed method is passivity-based controllers with time varying gains which depend on the rate of change of time varying delay. In our proposed method, stability condition is independent of the magnitude of the communication delay and the damping of the system. The delay-independent stability is shown via Lyapunov stability methods. Several experimental results show the effectiveness o...

  18. [Striated and delayed nephrography].

    Science.gov (United States)

    Marlois, O; Padovani, J; Faure, F; Devred, P; Grangier, M L; Panuel, M

    1985-10-01

    About a case of striated and delayed nephrogram seen on a diabetic child, authors come back to the different etiologies. Among them, the tubular precipitation of Tamm-Horsfall protein seems to be given like on the right possibilities. Whatever is its etiology, the mechanism of striated appearance is always the same, being founded on the radiated disposal of the collecting ducts and on a tubular stasis beeing with iodine concentration.

  19. Theoretical Delay Time Distributions

    CERN Document Server

    Nelemans, Gijs; Bours, Madelon

    2012-01-01

    We briefly discuss the method of population synthesis to calculate theoretical delay time distributions of type Ia supernova progenitors. We also compare the results of the different research groups and conclude that although one of the main differences in the results for single degenerate progenitors is the retention efficiency with which accreted hydrogen is added to the white dwarf core, this cannot explain all the differences.

  20. Theoretical Delay Time Distributions

    Science.gov (United States)

    Nelemans, Gijs; Toonen, Silvia; Bours, Madelon

    2013-01-01

    We briefly discuss the method of population synthesis to calculate theoretical delay time distributions of Type Ia supernova progenitors. We also compare the results of different research groups and conclude that, although one of the main differences in the results for single degenerate progenitors is the retention efficiency with which accreted hydrogen is added to the white dwarf core, this alone cannot explain all the differences.

  1. Geometric Time Delay Interferometry

    OpenAIRE

    Vallisneri, Michele

    2005-01-01

    The space-based gravitational-wave observatory LISA, a NASA-ESA mission to be launched after 2012, will achieve its optimal sensitivity using Time Delay Interferometry (TDI), a LISA-specific technique needed to cancel the otherwise overwhelming laser noise in the inter-spacecraft phase measurements. The TDI observables of the Michelson and Sagnac types have been interpreted physically as the virtual measurements of a synthesized interferometer. In this paper, I present Geometric TDI, a new an...

  2. Time-Delay Interferometry

    OpenAIRE

    Dhurandhar Sanjeev V.; Tinto Massimo

    2005-01-01

    Equal-arm interferometric detectors of gravitational radiation allow phase measurements many orders of magnitude below the intrinsic phase stability of the laser injecting light into their arms. This is because the noise in the laser light is common to both arms, experiencing exactly the same delay, and thus cancels when it is differenced at the photo detector. In this situation, much lower level secondary noises then set overall performance. If, however, the two arms have different lengths (...

  3. Delay in atomic photoionization

    CERN Document Server

    Kheifets, A S

    2010-01-01

    We analyze the time delay between emission of photoelectrons from the outer valence $ns$ and $np$ sub-shells in noble gas atoms following absorption of an attosecond XUV pulse. By solving the time dependent Schr\\"odinger equation and carefully examining the time evolution of the photoelectron wave packet, we establish the apparent "time zero" when the photoelectron leaves the atom. Various processes such as elastic scattering of the photoelectron on the parent ion and many-electron correlation affect the quantum phase of the dipole transition matrix element, the energy dependence of which defines the emission timing. This qualitatively explains the time delay between photoemission from the $2s$ and $2p$ sub-shells of Ne as determined experimentally by attosecond streaking [{\\em Science} {\\bf 328}, 1658 (2010)]. However, with our extensive numerical modeling, we were only able to account for less than a half of the measured time delay of $21\\pm5$~as. We argue that the XUV pulse alone cannot produce such a larg...

  4. Time-Delay Interferometry

    Directory of Open Access Journals (Sweden)

    Massimo Tinto

    2014-08-01

    Full Text Available Equal-arm detectors of gravitational radiation allow phase measurements many orders of magnitude below the intrinsic phase stability of the laser injecting light into their arms. This is because the noise in the laser light is common to both arms, experiencing exactly the same delay, and thus cancels when it is differenced at the photo detector. In this situation, much lower level secondary noises then set the overall performance. If, however, the two arms have different lengths (as will necessarily be the case with space-borne interferometers, the laser noise experiences different delays in the two arms and will hence not directly cancel at the detector. In order to solve this problem, a technique involving heterodyne interferometry with unequal arm lengths and independent phase-difference readouts has been proposed. It relies on properly time-shifting and linearly combining independent Doppler measurements, and for this reason it has been called time-delay interferometry (TDI. This article provides an overview of the theory, mathematical foundations, and experimental aspects associated with the implementation of TDI. Although emphasis on the application of TDI to the Laser Interferometer Space Antenna (LISA mission appears throughout this article, TDI can be incorporated into the design of any future space-based mission aiming to search for gravitational waves via interferometric measurements. We have purposely left out all theoretical aspects that data analysts will need to account for when analyzing the TDI data combinations.

  5. Delayed Speech or Language Development

    Science.gov (United States)

    ... to 2-Year-Old Delayed Speech or Language Development KidsHealth > For Parents > Delayed Speech or Language Development ... child is right on schedule. Normal Speech & Language Development It's important to discuss early speech and language ...

  6. Fictional Separation Logic

    DEFF Research Database (Denmark)

    Jensen, Jonas Buhrkal; Birkedal, Lars

    2012-01-01

    , separation means physical separation. In this paper, we introduce \\emph{fictional separation logic}, which includes more general forms of fictional separating conjunctions P * Q, where "*" does not require physical separation, but may also be used in situations where the memory resources described by P and Q...

  7. Delay Choice vs. Delay Maintenance: Different Measures of Delayed Gratification in Capuchin Monkeys (Cebus apella)

    Science.gov (United States)

    Addessi, Elsa; Paglieri, Fabio; Beran, Michael J.; Evans, Theodore A.; Macchitella, Luigi; De Petrillo, Francesca; Focaroli, Valentina

    2013-01-01

    Delaying gratification involves two components: (i) delay choice (selecting a delayed reward over an immediate one), and (ii) delay maintenance (sustaining the decision to delay gratification even if the immediate reward is available during the delay). In primates, two tasks most commonly have explored these components, the Intertemporal choice task and the Accumulation task. It is unclear whether these tasks provide equivalent measures of delay of gratification. Here, we compared the performance of the same capuchin monkeys, belonging to two study populations, between these tasks. We found only limited evidence of a significant correlation in performance. Consequently, in contrast to what is often assumed, our data provide only partial support to the hypothesis that these tasks provide equivalent measures of delay of gratification. PMID:23544770

  8. Experimental delayed-choice entanglement swapping

    Science.gov (United States)

    Ma, Xiao-Song; Zotter, Stefan; Kofler, Johannes; Ursin, Rupert; Jennewein, Thomas; Brukner, Časlav; Zeilinger, Anton

    2012-06-01

    Motivated by the question of which kind of physical interactions and processes are needed for the production of quantum entanglement, Peres has put forward the radical idea of delayed-choice entanglement swapping. There, entanglement can be `produced a posteriori, after the entangled particles have been measured and may no longer exist'. Here, we report the realization of Peres's gedanken experiment. Using four photons, we can actively delay the choice of measurement--implemented through a high-speed tunable bipartite-state analyser and a quantum random-number generator--on two of the photons into the time-like future of the registration of the other two photons. This effectively projects the two already registered photons onto one of two mutually exclusive quantum states in which the photons are either entangled (quantum correlations) or separable (classical correlations). This can also be viewed as `quantum steering into the past'.

  9. Experimental delayed-choice entanglement swapping

    CERN Document Server

    Ma, Xiao-song; Kofler, Johannes; Ursin, Rupert; Jennewein, Thomas; Brukner, Časlav; Zeilinger, Anton

    2012-01-01

    Motivated by the question, which kind of physical interactions and processes are needed for the production of quantum entanglement, Peres has put forward the radical idea of delayed-choice entanglement swapping. There, entanglement can be "produced a posteriori, after the entangled particles have been measured and may no longer exist". In this work we report the first realization of Peres' gedanken experiment. Using four photons, we can actively delay the choice of measurement-implemented via a high-speed tunable bipartite state analyzer and a quantum random number generator-on two of the photons into the time-like future of the registration of the other two photons. This effectively projects the two already registered photons onto one definite of two mutually exclusive quantum states in which either the photons are entangled (quantum correlations) or separable (classical correlations). This can also be viewed as "quantum steering into the past".

  10. Delaying information search

    Directory of Open Access Journals (Sweden)

    Yaniv Shani

    2012-11-01

    Full Text Available In three studies, we examined factors that may temporarily attenuate information search. People are generally curious and dislike uncertainty, which typically encourages them to look for relevant information. Despite these strong forces that promote information search, people sometimes deliberately delay obtaining valuable information. We find they may do so when they are concerned that the information might interfere with future pleasurable activities. Interestingly, the decision to search or to postpone searching for information is influenced not only by the value and importance of the information itself but also by well-being maintenance goals related to possible detrimental effects that negative knowledge may have on unrelated future plans.

  11. Separation Anxiety (For Parents)

    Science.gov (United States)

    ... Kids to Be Smart About Social Media Separation Anxiety KidsHealth > For Parents > Separation Anxiety Print A A ... both of you get through it. About Separation Anxiety Babies adapt pretty well to other caregivers. Parents ...

  12. Separation Anxiety (For Parents)

    Science.gov (United States)

    ... Feeding Your 1- to 2-Year-Old Separation Anxiety KidsHealth > For Parents > Separation Anxiety A A A ... both of you get through it. About Separation Anxiety Babies adapt pretty well to other caregivers. Parents ...

  13. Pseudotumoral delayed cerebral radionecrosis

    Energy Technology Data Exchange (ETDEWEB)

    Ciaudo-Lacroix, C.; Lapresle, J. (Centre Hospitalier de Bicetre, 94 - Le Kremlin-Bicetre (France))

    1985-01-01

    A 60 year-old woman with a scalp epithelioma underwent radiotherapy, the dose being 57 Gray. A first epileptic seizure occurred twenty months later. Neurological examination revealed signs of left hemisphere involvement. ..gamma..EG, angiography, CT scans, demonstrated a pseudotumoral avascular process. On account of the localisation, the patient being right-handed, no surgical procedure was performed. In spite of corticotherapy and anticonvulsive treatment, seizures recurred and neurological signs slowly progressed. The patient died, 22 months after the first seizure, of an associated disseminated carcinoma with cachexia. Neuropathological examination showed a massive lesion presenting all the features of delayed radionecrosis in the left hemisphere: situated mainly in the white matter; numerous vascular abnormalities; wide-spread demyelination; disappearance of oligoglial cells. The Authors recall the clinical and anatomical aspects of this condition for which the only successful treatment is surgical removal when location and size of the lesion permit. Finally, the mechanisms which have been proposed to explain this delayed cerebral radionecrosis are discussed.

  14. Epidemiology of delayed ejaculation.

    Science.gov (United States)

    Di Sante, Stefania; Mollaioli, Daniele; Gravina, Giovanni Luca; Ciocca, Giacomo; Limoncin, Erika; Carosa, Eleonora; Lenzi, Andrea; Jannini, Emmanuele A

    2016-08-01

    A large body of literature on diminished ejaculatory disorders has been generated without the use of a clear diagnostic definition. Many studies have not distinguished between the orgasm and ejaculation disorders leading to doubtful results. Delayed ejaculation (DE) is one of the diminished ejaculatory disorders, which range from varying delays in ejaculatory latency to a complete inability to ejaculate. The present review is aimed at providing a comprehensive overview of the current knowledge on the definition and epidemiology of diminished ejaculatory disorders. We focus on the acquired diseases, such as benign prostatic hyperplasia (BPH) and specific drug regimens that may cause an iatrogenic form of ejaculatory disorder. In addition, the impact of aging is discussed since the prevalence of DE appears to be moderately but positively related to age. Finally, we also focus on the importance of the hormonal milieu on male ejaculation. To date, evidence on the endocrine control of ejaculation is derived from small clinical trials, but the evidence suggests that hormones modulate the ejaculatory process by altering its overall latency.

  15. Stability and delay sensitivity of neutral fractional-delay systems

    Science.gov (United States)

    Xu, Qi; Shi, Min; Wang, Zaihua

    2016-08-01

    This paper generalizes the stability test method via integral estimation for integer-order neutral time-delay systems to neutral fractional-delay systems. The key step in stability test is the calculation of the number of unstable characteristic roots that is described by a definite integral over an interval from zero to a sufficient large upper limit. Algorithms for correctly estimating the upper limits of the integral are given in two concise ways, parameter dependent or independent. A special feature of the proposed method is that it judges the stability of fractional-delay systems simply by using rough integral estimation. Meanwhile, the paper shows that for some neutral fractional-delay systems, the stability is extremely sensitive to the change of time delays. Examples are given for demonstrating the proposed method as well as the delay sensitivity.

  16. Synchronizing time delay systems using variable delay in coupling

    Energy Technology Data Exchange (ETDEWEB)

    Ambika, G., E-mail: g.ambika@iiserpune.ac.in [Indian Institute of Science Education and Research, Pune 411 021 (India); Amritkar, R.E., E-mail: amritkar@prl.res.in [Physical Research Laboratory, Ahmedabad 380 009 (India)

    2011-11-15

    Highlights: > Delay and anticipation in coupling function varies with system dynamics. > Delay or anticipation of the synchronized state is independent of system delay. > Stability analysis developed is quite general. > We demonstrate enhanced security in communication. > Generalized synchronization possible over a wide range of parameter mismatch. - Abstract: We present a mechanism for synchronizing time delay systems using one way coupling with a variable delay in coupling that is reset at finite intervals. We present the analysis of the error dynamics that helps to isolate regions of stability of the synchronized state in the parameter space of interest for single and multiple delays. We supplement this by numerical simulations in a standard time delay system like Mackey Glass system. This method has the advantage that it can be adjusted to be delay or anticipatory in synchronization with a time which is independent of the system delay. We demonstrate the use of this method in communication using the bi channel scheme. We show that since the synchronizing channel carries information from transmitter only at intervals of reset time, it is not susceptible to an easy reconstruction.

  17. Small delay approximation of stochastic delay differential equations

    Science.gov (United States)

    Guillouzic, Steve; L'heureux, Ivan; Longtin, André

    1999-04-01

    Delay differential equations evolve in an infinite-dimensional phase space. In this paper, we consider the effect of external fluctuations (noise) on delay differential equations involving one variable, thus leading to univariate stochastic delay differential equations (SDDE's). For small delays, a univariate nondelayed stochastic differential equation approximating such a SDDE is presented. Another approximation, complementary to the first, is also obtained using an average of the SDDE's drift term over the delayed dynamical variable, which defines a conditional average drift. This second approximation is characterized by the fact that the diffusion term is identical to that of the original SDDE. For small delays, our approach yields a steady-state probability density and a conditional average drift which are in close agreement with numerical simulations of the original SDDE. We illustrate this scheme with the delayed linear Langevin equation and a stochastic version of the delayed logistic equation. The technique can be used with any type of noise, and is easily generalized to multiple delays.

  18. Delay tolerant networks

    CERN Document Server

    Gao, Longxiang; Luan, Tom H

    2015-01-01

    This brief presents emerging and promising communication methods for network reliability via delay tolerant networks (DTNs). Different from traditional networks, DTNs possess unique features, such as long latency and unstable network topology. As a result, DTNs can be widely applied to critical applications, such as space communications, disaster rescue, and battlefield communications. The brief provides a complete investigation of DTNs and their current applications, from an overview to the latest development in the area. The core issue of data forward in DTNs is tackled, including the importance of social characteristics, which is an essential feature if the mobile devices are used for human communication. Security and privacy issues in DTNs are discussed, and future work is also discussed.

  19. Controlling Separation in Turbomachines

    Science.gov (United States)

    Evans, Simon; Himmel, Christoph; Power, Bronwyn; Wakelam, Christian; Xu, Liping; Hynes, Tom; Hodson, Howard

    2010-01-01

    Four examples of flow control: 1) Passive control of LP turbine blades (Laminar separation control). 2) Aspiration of a conventional axial compressor blade (Turbulent separation control). 3) Compressor blade designed for aspiration (Turbulent separation control). 4.Control of intakes in crosswinds (Turbulent separation control).

  20. On the Gravitomagnetic Time Delay

    OpenAIRE

    Ciufolini, I.; Kopeikin, S.; Mashhoon, B.; Ricci, F

    2002-01-01

    We study the gravitational time delay in ray propagation due to rotating masses in the linear approximation of general relativity. Simple expressions are given for the gravitomagnetic time delay that occurs when rays of radiation cross a slowly rotating shell and propagate in the field of a distant rotating source. Moreover, we calculate the local gravitational time delay in the Goedel universe. The observational consequences of these results in the case of weak gravitational lensing are disc...

  1. Demographic determinants of delayed divorce.

    Science.gov (United States)

    Chan, L Y; Heaton, T B

    1989-01-01

    This study identifies factors that predict delayed divorce in the US. The findings show that factors which influence marital stability in general also correlate with delayed divorce in the same direction. Wife's age at marriage, age of the youngest child, wife's religion, region of residence, and metropolitan residence have substantial effects of delayed divorce, but the effects of race, parental divorce, premarital pregnancy, and socioeconomic status are small.

  2. Location Estimation using Delayed Measurements

    DEFF Research Database (Denmark)

    Bak, Martin; Larsen, Thomas Dall; Nørgård, Peter Magnus

    1998-01-01

    When combining data from various sensors it is vital to acknowledge possible measurement delays. Furthermore, the sensor fusion algorithm, often a Kalman filter, should be modified in order to handle the delay. The paper examines different possibilities for handling delays and applies a new techn...... technique to a sensor fusion system for estimating the location of an autonomous guided vehicle. The system fuses encoder and vision measurements in an extended Kalman filter. Results from experiments in a real environment are reported...

  3. Chaotifying delayed recurrent neural networks via impulsive effects

    Science.gov (United States)

    Şaylı, Mustafa; Yılmaz, Enes

    2016-02-01

    In this paper, chaotification of delayed recurrent neural networks via chaotically changing moments of impulsive actions is considered. Sufficient conditions for the presence of Li-Yorke chaos with its ingredients proximality, frequent separation, and existence of infinitely many periodic solutions are theoretically proved. Finally, effectiveness of our theoretical results is illustrated by an example with numerical simulations.

  4. Bounded Delay Timing Analysis of a Class of CSP Programs

    DEFF Research Database (Denmark)

    Hulgaard, Henrik; Burns, Steven M.

    1997-01-01

    . Such a description is transformed into a safe Petri net with interval time delays specified on the places of the net. The timing analysis we perform determines the extreme separation in time between two communication actions of the CSP program for all possible timed executions of the system. We formally define...

  5. Concurrent Delay in Construction Disputes

    DEFF Research Database (Denmark)

    Cavaleri, Sylvie Cécile

    period of delay can potentially be attributed to several events falling within both parties' spheres of responsibility, commonly termed concurrent delay, is rarely regulated in construction contracts in spite of its common occurrence. This book analyses both the theoretical foundations and the practical......Delay is one of the issues most frequently encountered in today’s construction industry; it causes significant economic damage to all parties involved. Construction contracts, standard and bespoke, almost invariably consider delay from a perspective of single liability. If the event causing...

  6. Concurrent Delay in Construction Disputes

    DEFF Research Database (Denmark)

    Cavaleri, Sylvie Cécile

    Delay is one of the issues most frequently encountered in today’s construction industry; it causes significant economic damage to all parties involved. Construction contracts, standard and bespoke, almost invariably consider delay from a perspective of single liability. If the event causing...... period of delay can potentially be attributed to several events falling within both parties' spheres of responsibility, commonly termed concurrent delay, is rarely regulated in construction contracts in spite of its common occurrence. This book analyses both the theoretical foundations and the practical...

  7. Workspace visualization and time-delay telerobotic operations

    Science.gov (United States)

    Schenker, P. S.; Bejczy, A. K.

    1990-01-01

    The paper examines the performance of telerobotic tasks where the operator and robot are physically separated, and a comunication time delay of up to several seconds between them exists. This situation is applicable to space robotic servicing-assembly-maintenance operations on low earth or geosynchronous orbits with a ground-based command station. Attention is given to two developments which address advanced time-delay teleoperations for unstructured tasks: (1) the 'phantom robot', a real-time predictive graphics simulator developed to allow teleoperator eye-to-hand coordination or robot free-space kinematics under a time delay of several seconds; and (2) shared compliance control, a modified form of automatic electromechanical impedance control employed in parallel with manual position control to permit soft contact and grasp compliance with workpiece geometry under a time delay of several seconds.

  8. Modeling biological systems with delays in Bio-PEPA

    CERN Document Server

    Caravagna, Giulio; 10.4204/EPTCS.40.7

    2010-01-01

    Delays in biological systems may be used to model events for which the underlying dynamics cannot be precisely observed, or to provide abstraction of some behavior of the system resulting more compact models. In this paper we enrich the stochastic process algebra Bio-PEPA, with the possibility of assigning delays to actions, yielding a new non-Markovian process algebra: Bio-PEPAd. This is a conservative extension meaning that the original syntax of Bio-PEPA is retained and the delay specification which can now be associated with actions may be added to existing Bio-PEPA models. The semantics of the firing of the actions with delays is the delay-as-duration approach, earlier presented in papers on the stochastic simulation of biological systems with delays. These semantics of the algebra are given in the Starting-Terminating style, meaning that the state and the completion of an action are observed as two separate events, as required by delays. Furthermore we outline how to perform stochastic simulation of Bio...

  9. Automated Methods to Maintain Aircraft Separation

    Science.gov (United States)

    Lauderdale, Todd

    2011-01-01

    The air traffic control system in the United States has a great track-record for safety. As more aircraft enter the system at a given time, the situation becomes more complex though. Researchers at NASA are attempting to leverage advances in many fields including optimization, data mining, and numerical modeling of systems to improve the air-transportation system maintaining safety while increasing throughput and reducing delays. This talk will give a brief overview of the research at NASA towards modernizing the air-transportation system. It will then focus on the specific area of automation tools for maintaining physical separation between aircraft known as Separation Assurance.

  10. Registration Delay and Student Performance

    Science.gov (United States)

    Siefken, Jason

    2017-01-01

    Tracking the difference between the time a first-year student is allowed to register for a course and the time he or she does register for a course (a student's registration delay), we notice a negative correlation between registration delay and final grade in a course. The difference between a student who registers within the first two minutes…

  11. 78 FR 59422 - Delayed Applications

    Science.gov (United States)

    2013-09-26

    ... Pipeline and Hazardous Materials Safety Administration Delayed Applications AGENCY: Office of Hazardous... applications delayed more than 180 days. SUMMARY: In accordance with the requirements of 49 U.S.C. 5117(c), PHMSA is publishing the following list of special permit applications that have been in process for 180...

  12. High resolution digital delay timer

    Science.gov (United States)

    Martin, Albert D.

    1988-01-01

    Method and apparatus are provided for generating an output pulse following a trigger pulse at a time delay interval preset with a resolution which is high relative to a low resolution available from supplied clock pulses. A first lumped constant delay (20) provides a first output signal (24) at predetermined interpolation intervals corresponding to the desired high resolution time interval. Latching circuits (26, 28) latch the high resolution data (24) to form a first synchronizing data set (60). A selected time interval has been preset to internal counters (142, 146, 154) and corrected for circuit propagation delay times having the same order of magnitude as the desired high resolution. Internal system clock pulses (32, 34) count down the counters to generate an internal pulse delayed by an interval which is functionally related to the preset time interval. A second LCD (184) corrects the internal signal with the high resolution time delay. A second internal pulse is then applied to a third LCD (74) to generate a second set of synchronizing data (76) which is complementary with the first set of synchronizing data (60) for presentation to logic circuits (64). The logic circuits (64) further delay the internal output signal (72) to obtain a proper phase relationship of an output signal (80) with the internal pulses (32, 34). The final delayed output signal (80) thereafter enables the output pulse generator (82) to produce the desired output pulse (84) at the preset time delay interval following input of the trigger pulse (10, 12).

  13. Calibrating for Ionospheric Phase Delays

    Science.gov (United States)

    Macdoran, P. F.

    1985-01-01

    Technique determines ionospheric phase delay on real-time universally applicable basis in terms of electrons per meter squared by coherently modulating two L-band carrier frequencies received from two Global Positioning System satelites. Two pseudorandom number sequences cross-correlated to derive delay time.

  14. #FakeNobelDelayReasons

    CERN Multimedia

    2013-01-01

    Tuesday’s hour-long delay of the Nobel Prize in Physics announcement was (and still is) quite the cause for speculation. But on the Twittersphere, it was simply the catalyst for some fantastic puns, so-bad-they're-good physics jokes and other shenanigans. Here are some of our favourite #FakeNobelDelayReasons.    

  15. Imitation dynamics with time delay.

    Science.gov (United States)

    Wang, Shi-Chang; Yu, Jie-Ru; Kurokawa, Shun; Tao, Yi

    2017-05-07

    Based on the classic imitation dynamics (Hofbauer and Sigmund, 1998, Evolutionary Games and Population Dynamics, Cambridge University Press), the imitation dynamics with time delay is investigated, where the probability that an individual will imitate its opponent's own strategy is assumed to depend on the comparison between the past expected payoff of this individual's own strategy and the past expected payoff of its opponent's own strategy, i.e. there is a time delay effect. For the two-phenotype model, we show that if the system has an interior equilibrium and this interior equilibrium is stable when there is no time delay, then there must be a critical value of time delay such that the system tends to a stable periodic solution when the time delay is larger than the critical value. On the other hand, for three-phenotype (rock-scissors-paper) model, the numerical analysis shows that for the stable periodic solution induced by the time delay, the amplitude and the period will increase with the increase of the time delay. These results should help to understand the evolution of behavior based on the imitation dynamics with time delay. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Magnetic bearing optical delay line

    NARCIS (Netherlands)

    Dool, T.C. van den; Kamphues, F.G.; Fouss, B.; Henrioulle, K.; Hogenhuis, H.

    2004-01-01

    TNO TPD, in close cooperation with Micromega-Dynamics and Dutch Space, has developed an advanced Optical Delay Line (ODL) for use in PRIMA, GENIE and other ground based interferometers. The delay line design is modular and flexible, which makes scaling for other applications a relatively easy task.

  17. Time-delay damping theory

    Institute of Scientific and Technical Information of China (English)

    洪峰

    2002-01-01

    In this paper, existing damping theories are briefly reviewed. On the basis of the existing damping theories, a new kind of damping theory, i.e., the time-delay damping theory, is developed. In the time-delay damping theory, the damping force is considered to be directly proportional to the increment of displacement. The response analysis of an SDOF time-delay damping system is carried out, and the methods for obtaining the solution for a time-delay damping system in the time domain as well as the frequency domain are given. The comparison between results from different damping theories shows that the time-delay damping theory is both reasonable and convenient.

  18. Asynchronous Bounded Expected Delay Networks

    CERN Document Server

    Bakhshi, Rena; Fokkink, Wan; Pang, Jun

    2010-01-01

    The commonly used asynchronous bounded delay (ABD) network models assume a fixed bound on message delay. We propose a probabilistic network model, called asynchronous bounded expected delay (ABE) model. Instead of a strict bound, the ABE model requires only a bound on the expected message delay. While the conditions of ABD networks restrict the set of possible executions, in ABE networks all asynchronous executions are possible, but executions with extremely long delays are less probable. In contrast to ABD networks, ABE networks cannot be synchronised efficiently. At the example of an election algorithm, we show that the minimal assumptions of ABE networks are sufficient for the development of efficient algorithms. For anonymous, unidirectional ABE rings of known size N we devise a probabilistic leader election algorithm having average message and time complexity O(N).

  19. Two-stage tubularized transverse preputial island flap and two-stage urethral plate reconstruction procedures in the treatment of severe hypospadias%分期管形包皮岛状皮瓣术式与分期尿道板重建卷管术式治疗重度尿道下裂的疗效比较

    Institute of Scientific and Technical Information of China (English)

    田军; 张潍平; 孙宁; 谢向辉; 李明磊; 宋宏程; 李宁; 黄澄如

    2016-01-01

    Objective To compare the treatment efficacy of severe hypospadias between two-stage urethral plate reconstruction procedure and two-stage tubularized transverse preputial island flap procedure. Methods From 2010 December to 2014 December, we retrospectively analyzed 82 cases with severe hypospadias, using two-stage urethral plate reconstruction and two-stage tubularized transverse preputial island flap urethroplasty, respectively.Their mean age in the first operation was 2.4 years, ranged from 2 to 3 years.Hypospadias were penoscrotal type in 32 cases, perineal type in 50 cases.In group A, 42 cases, including penoscrotal type in 15 cases, perineal type in 27 cases, with urethral plate reconstruction procedure underwent two-stage urethroplasty.The transected ventral penile urethral plate and to strip the ventral fibrous tissue were needed in correction of chordee of penis.The patients in group A were underwent the second urethroplasty with urethral plate reconstruction procedure 6-12 months later.In group B, 40 cases,including penoscrotal type in 17 cases, perineal type in 23 cases, who underwent one stage operation in the correction of chordee of penis, only with tubularized preputial island flap forming the part of the urethra.The patients in group B were underwent the second urethroplasty 6 ~12 months later.Results Patients were followed up for 1 to 5 years, mean 3.5 years.No recurrence of penis chordee was noticed.In group A, 6 cases (14.3%) had postoperative fistula.The second fistula repairing was perform 6 to 12 months after the second stage operation.However, still 3 cases were noticed the fistula recurrence, which was cured after the fourth operation.In group B, 3 cases (7.5%) developed fistula, which appeared in the second urethroplasty (P<0.01).They were all treated after the second repairing procedure.In group A, 4 cases were noticed urethral stricture, the urethral stricture rate was 9.5%.The stricture occurred 1 to 3 months after the second operation

  20. Separation anxiety in children

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/001542.htm Separation anxiety in children To use the sharing features on this page, please enable JavaScript. Separation anxiety in children is a developmental stage in which ...

  1. Ionene membrane battery separator

    Science.gov (United States)

    Moacanin, J.; Tom, H. Y.

    1969-01-01

    Ionic transport characteristics of ionenes, insoluble membranes from soluble polyelectrolyte compositions, are studied for possible application in a battery separator. Effectiveness of the thin film of separator membrane essentially determines battery lifetime.

  2. Magnetic separation of algae

    Energy Technology Data Exchange (ETDEWEB)

    Nath, Pulak; Twary, Scott N.

    2016-04-26

    Described herein are methods and systems for harvesting, collecting, separating and/or dewatering algae using iron based salts combined with a magnetic field gradient to separate algae from an aqueous solution.

  3. Delayed radiation neuropathy

    Energy Technology Data Exchange (ETDEWEB)

    Nagashima, T.; Miyamoto, K.; Beppu, H.; Hirose, K.; Yamada, K. (Tokyo Metropolitan Neurological Hospital (Japan))

    1981-07-01

    A case of cervical plexus neuropathy was reported in association with chronic radio-dermatitis, myxedema with thyroid adenoma and epiglottic tumor. A 38-year-old man has noticed muscle weakness and wasting of the right shoulder girdle since age 33. A detailed history taking revealed a previous irradiation to the neck because of the cervical lymphadenopathy at age 10 (X-ray 3,000 rads), keroid skin change at age 19, obesity and edema since 26, and hoarseness at 34. Laryngoscopic examination revealed a tumor on the right vocal cord, diagnosed as benign papilloma by histological study. In addition, there were chronic radio-dermatitis around the neck, primary hypothyroidism with a benign functioning adenoma on the right lobe of the thyroid, the right phrenic nerve palsy and the right recurrent nerve palsy. All these lesions were considered to be the late sequellae of radiation to the neck in childhood. Other neurological signs were weakness and amyotrophy of the right shoulder girdle with patchy sensory loss, and areflexia of the right arm. Gross power was fairly well preserved in the right hand. EMG showed neurogenic changes in the tested muscles, suggesting a peripheral nerve lesion. Nerve conduction velocities were normal. No abnormal findings were revealed by myelography and spinal CT. The neurological findings of the patient were compatible with the diagnosis of middle cervical plexus palsy apparently due to late radiation effect. In the literature eight cases of post-radiation neuropathy with a long latency have been reported. The present case with the longest latency after the radiation should be included in the series of the reported cases of ''delayed radiation neuropathy.'' (author).

  4. Kinetic Gravity Separation

    NARCIS (Netherlands)

    Van Kooy, L.; Mooij, M.; Rem, P.

    2004-01-01

    Separations by density, such as the separation of non-ferrous scrap into light and heavy alloys, are often realized by means of heavy media. In principle, kinetic gravity separations in water can be faster and cheaper, because they do not rely on suspensions or salt solutions of which the density

  5. A Very Common Fallacy in Quantum Mechanics: Superposition, Delayed Choice, Quantum Erasers, Retrocausality, and All That

    CERN Document Server

    Ellerman, David

    2011-01-01

    There is a very common fallacy, here called the separation fallacy, that is involved in the interpretation of quantum experiments involving a certain type of separation such as the: double-slit experiments, which-way interferometer experiments, polarization analyzer experiments, Stern-Gerlach experiments, and quantum eraser experiments. It is the separation fallacy that leads not only to flawed textbook accounts of these experiments but to flawed inferences about retrocausality in the context of "delayed choice" versions of separation experiments.

  6. Rapid chemical separations

    CERN Document Server

    Trautmann, N

    1976-01-01

    A survey is given on the progress of fast chemical separation procedures during the last few years. Fast, discontinuous separation techniques are illustrated by a procedure for niobium. The use of such techniques for the chemical characterization of the heaviest known elements is described. Other rapid separation methods from aqueous solutions are summarized. The application of the high speed liquid chromatography to the separation of chemically similar elements is outlined. The use of the gas jet recoil transport method for nuclear reaction products and its combination with a continuous solvent extraction technique and with a thermochromatographic separation is presented. Different separation methods in the gas phase are briefly discussed and the attachment of a thermochromatographic technique to an on-line mass separator is shown. (45 refs).

  7. Acoustofluidic bacteria separation

    Science.gov (United States)

    Li, Sixing; Ma, Fen; Bachman, Hunter; Cameron, Craig E.; Zeng, Xiangqun; Huang, Tony Jun

    2017-01-01

    Bacterial separation from human blood samples can help with the identification of pathogenic bacteria for sepsis diagnosis. In this work, we report an acoustofluidic device for label-free bacterial separation from human blood samples. In particular, we exploit the acoustic radiation force generated from a tilted-angle standing surface acoustic wave (taSSAW) field to separate Escherichia coli from human blood cells based on their size difference. Flow cytometry analysis of the E. coli separated from red blood cells shows a purity of more than 96%. Moreover, the label-free electrochemical detection of the separated E. coli displays reduced non-specific signals due to the removal of blood cells. Our acoustofluidic bacterial separation platform has advantages such as label-free separation, high biocompatibility, flexibility, low cost, miniaturization, automation, and ease of in-line integration. The platform can be incorporated with an on-chip sensor to realize a point-of-care sepsis diagnostic device.

  8. Time Delay in Molecular Photoionization

    CERN Document Server

    Hockett, P; Villeneuve, D M; Corkum, P B

    2015-01-01

    Time-delays in the photoionization of molecules are investigated. As compared to atomic ionization, the time-delays expected from molecular ionization present a much richer phenomenon, with a strong spatial dependence due to the anisotropic nature of the molecular scattering potential. We investigate this from a scattering theory perspective, and make use of molecular photoionization calculations to examine this effect in representative homonuclear and hetronuclear diatomic molecules, nitrogen and carbon monoxide. We present energy and angle-resolved maps of the Wigner delay time for single-photon valence ionization, and discuss the possibilities for experimental measurements.

  9. Leibniz Dynamics with Time Delay

    OpenAIRE

    Albu, I. D.; Opris, D.

    2005-01-01

    In this paper we show that several dynamical systems with time delay can be described as vector fields associated to smooth functions via a bracket of Leibniz structure. Some examples illustrate the theoretical considerations.

  10. Delays and networked control systems

    CERN Document Server

    Hetel, Laurentiu; Daafouz, Jamal; Johansson, Karl

    2016-01-01

    This edited monograph includes state-of-the-art contributions on continuous time dynamical networks with delays. The book is divided into four parts. The first part presents tools and methods for the analysis of time-delay systems with a particular attention on control problems of large scale or infinite-dimensional systems with delays. The second part of the book is dedicated to the use of time-delay models for the analysis and design of Networked Control Systems. The third part of the book focuses on the analysis and design of systems with asynchronous sampling intervals which occur in Networked Control Systems. The last part of the book exposes several contributions dealing with the design of cooperative control and observation laws for networked control systems. The target audience primarily comprises researchers and experts in the field of control theory, but the book may also be beneficial for graduate students. .

  11. A Kac CROW Delay Line

    CERN Document Server

    Sumetsky, M

    2013-01-01

    A low-loss CROW delay line with a weak inter-resonator coupling determined by the Kac matrix is dispersionless and can be easily impedance-matched by adjusting the coupling to the input/output waveguide.

  12. Systematics in delayed neutron yields

    Energy Technology Data Exchange (ETDEWEB)

    Ohsawa, Takaaki [Kinki Univ., Higashi-Osaka, Osaka (Japan). Atomic Energy Research Inst.

    1998-03-01

    An attempt was made to reproduce the systematic trend observed in the delayed neutron yields for actinides on the basis of the five-Gaussian representation of the fission yield together with available data sets for delayed neutron emission probability. It was found that systematic decrease in DNY for heavier actinides is mainly due to decrease of fission yields of precursors in the lighter side of the light fragment region. (author)

  13. Time Delay in Molecular Photoionization

    OpenAIRE

    Hockett, P.; Frumker, E.; Villeneuve, D M; Corkum, P. B.

    2015-01-01

    Time-delays in the photoionization of molecules are investigated. As compared to atomic ionization, the time-delays expected from molecular ionization present a much richer phenomenon, with a strong spatial dependence due to the anisotropic nature of the molecular scattering potential. We investigate this from a scattering theory perspective, and make use of molecular photoionization calculations to examine this effect in representative homonuclear and hetronuclear diatomic molecules, nitroge...

  14. Measuring information-transfer delays.

    Directory of Open Access Journals (Sweden)

    Michael Wibral

    Full Text Available In complex networks such as gene networks, traffic systems or brain circuits it is important to understand how long it takes for the different parts of the network to effectively influence one another. In the brain, for example, axonal delays between brain areas can amount to several tens of milliseconds, adding an intrinsic component to any timing-based processing of information. Inferring neural interaction delays is thus needed to interpret the information transfer revealed by any analysis of directed interactions across brain structures. However, a robust estimation of interaction delays from neural activity faces several challenges if modeling assumptions on interaction mechanisms are wrong or cannot be made. Here, we propose a robust estimator for neuronal interaction delays rooted in an information-theoretic framework, which allows a model-free exploration of interactions. In particular, we extend transfer entropy to account for delayed source-target interactions, while crucially retaining the conditioning on the embedded target state at the immediately previous time step. We prove that this particular extension is indeed guaranteed to identify interaction delays between two coupled systems and is the only relevant option in keeping with Wiener's principle of causality. We demonstrate the performance of our approach in detecting interaction delays on finite data by numerical simulations of stochastic and deterministic processes, as well as on local field potential recordings. We also show the ability of the extended transfer entropy to detect the presence of multiple delays, as well as feedback loops. While evaluated on neuroscience data, we expect the estimator to be useful in other fields dealing with network dynamics.

  15. Basin stability in delayed dynamics

    Science.gov (United States)

    Leng, Siyang; Lin, Wei; Kurths, Jürgen

    2016-02-01

    Basin stability (BS) is a universal concept for complex systems studies, which focuses on the volume of the basin of attraction instead of the traditional linearization-based approach. It has a lot of applications in real-world systems especially in dynamical systems with a phenomenon of multi-stability, which is even more ubiquitous in delayed dynamics such as the firing neurons, the climatological processes, and the power grids. Due to the infinite dimensional property of the space for the initial values, how to properly define the basin’s volume for delayed dynamics remains a fundamental problem. We propose here a technique which projects the infinite dimensional initial state space to a finite-dimensional Euclidean space by expanding the initial function along with different orthogonal or nonorthogonal basis. A generalized concept of basin’s volume in delayed dynamics and a highly practicable calculating algorithm with a cross-validation procedure are provided to numerically estimate the basin of attraction in delayed dynamics. We show potential applicabilities of this approach by applying it to study several representative systems of biological or/and physical significance, including the delayed Hopfield neuronal model with multistability and delayed complex networks with synchronization dynamics.

  16. [Separation anxiety in children].

    Science.gov (United States)

    Purper-Ouakil, Diane; Franc, Nathalie

    2010-06-20

    Separation anxiety disorder can be differentiated from developmental anxiety because of its intensity, persistence and negative impact on adaptive functioning. This disorder is closely linked to other anxiety and mood disorders and can also be associated with externalizing psychopathology in children and adolescents. Severe separation anxiety can result in school refusal and intra-familial violence. Cognitive behavioral therapies have the best evidence-based support for the treatment of separation anxiety disorder in children and adolescents. In addition, it is important to detect factors associated with persistence of anxiety such as systematic avoidance of separation and parental overprotection. The role of pediatricians and general practitioners in recognizing clinical separation anxiety and encouraging appropriate care and positive parental attitudes is essential, as separation anxiety is often associated with a variety of somatic symptoms.

  17. [Separation anxiety. Theoretical considerations].

    Science.gov (United States)

    Blandin, N; Parquet, P J; Bailly, D

    1994-01-01

    The interest in separation anxiety is nowadays increasing: this disorder appearing during childhood may predispose to the occurrence of anxiety disorders (such as panic disorder and agoraphobia) and major depression into adulthood. Psychoanalytic theories differ on the nature of separation anxiety and its place in child development. For some authors, separation anxiety must be understood as resulting from the unconscious internal conflicts inherent in the individuation process and gradual attainment of autonomy. From this point of view, the fear of loss of mother by separation is not regarded as resulting from a real danger. However, Freud considers the primary experience of separation from protecting mother as the prototype situation of anxiety and compares the situations generating fear to separation experiences. For him, anxiety originates from two factors: the physiological fact is initiated at the time of birth but the primary traumatic situation is the separation from mother. This point of view may be compared with behavioral theories. Behavioral theories suggest that separation anxiety may be conditioned or learned from innate fears. In Freud's theory, the primary situation of anxiety resulting from the separation from mother plays a role comparable to innate fears. Grappling with the problem of separation anxiety, Bowlby emphasizes then the importance of the child's attachment to one person (mother or primary caregiver) and the fact that this attachment is instinctive. This point of view, based on the watch of infants, is akin to ethological theories on behaviour of non human primates. Bowlby especially shows that the reactions of infant separated from mother evolve on three stages: the phase of protestation which may constitute the prototype of adulthood anxiety, the phase of desperation which may be the prototype of depression, and the phase of detachment. He emphasizes so the role of early separations in the development of vulnerability to depression

  18. Separation of flow

    CERN Document Server

    Chang, Paul K

    2014-01-01

    Interdisciplinary and Advanced Topics in Science and Engineering, Volume 3: Separation of Flow presents the problem of the separation of fluid flow. This book provides information covering the fields of basic physical processes, analyses, and experiments concerning flow separation.Organized into 12 chapters, this volume begins with an overview of the flow separation on the body surface as discusses in various classical examples. This text then examines the analytical and experimental results of the laminar boundary layer of steady, two-dimensional flows in the subsonic speed range. Other chapt

  19. Effect of temporal separation on synchronization in rhythmic performance.

    Science.gov (United States)

    Chafe, Chris; Cáceres, Juan-Pablo; Gurevich, Michael

    2010-01-01

    A variety of short time delays inserted between pairs of subjects were found to affect their ability to synchronize a musical task. The subjects performed a clapping rhythm together from separate sound-isolated rooms via headphones and without visual contact. One-way time delays between pairs were manipulated electronically in the range of 3 to 78 ms. We are interested in quantifying the envelope of time delay within which two individuals produce synchronous performances. The results indicate that there are distinct regimes of mutually coupled behavior, and that 'natural time delay'--delay within the narrow range associated with travel times across spatial arrangements of groups and ensembles--supports the most stable performance. Conditions outside of this envelope, with time delays both below and above it, create characteristic interaction dynamics in the mutually coupled actions of the duo. Trials at extremely short delays (corresponding to unnaturally close proximity) had a tendency to accelerate from anticipation. Synchronization lagged at longer delays (larger than usual physical distances) and produced an increasingly severe deceleration and then deterioration of performed rhythms. The study has implications for music collaboration over the Internet and suggests that stable rhythmic performance can be achieved by 'wired ensembles' across distances of thousands of kilometers.

  20. The separation of adult separation anxiety disorder.

    Science.gov (United States)

    Baldwin, David S; Gordon, Robert; Abelli, Marianna; Pini, Stefano

    2016-08-01

    The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) categorization of mental disorders places "separation anxiety disorder" within the broad group of anxiety disorders, and its diagnosis no longer rests on establishing an onset during childhood or adolescence. In previous editions of DSM, it was included within the disorders usually first diagnosed in infancy, childhood, or adolescence, with the requirement for an onset of symptoms before the age of 18 years: symptomatic adults could only receive a retrospective diagnosis, based on establishing this early onset. The new position of separation anxiety disorder is based upon the findings of epidemiological studies that revealed the unexpectedly high prevalence of the condition in adults, often in individuals with an onset of symptoms after the teenage years; its prominent place within the DSM-5 group of anxiety disorders should encourage further research into its epidemiology, etiology, and treatment. This review examines the clinical features and boundaries of the condition, and offers guidance on how it can be distinguished from other anxiety disorders and other mental disorders in which "separation anxiety" may be apparent.

  1. The Consequences of Delaying Entrance into University

    DEFF Research Database (Denmark)

    Foley, Kelly; Groes, Fane

    Because the returns to education depend on the nite horizon of individuals' working lives, human capital models predict that if an individual is going to attend university, she should do so as soon as possible. Delaying university can also mean individuals have fewer years in which to accumulate...... that compared to other programs, Arts and Humanities graduates have flatter wage profiles. These flatter profiles in turn mean that the experience-related wage losses are smaller. For Arts graduates the wage penalty is never more than six per cent. In contrast, the penalty for Social Science graduates who...... university will be larger when the returns to experience are higher. Using a panel covering 10 years of post-schooling wages, we estimate the returns to experience separately for graduates in different fields of study. We find important dierences in wage proles across the elds of study. Specically, we find...

  2. Electrocardiogram classification using delay differential equations

    Science.gov (United States)

    Lainscsek, Claudia; Sejnowski, Terrence J.

    2013-06-01

    Time series analysis with nonlinear delay differential equations (DDEs) reveals nonlinear as well as spectral properties of the underlying dynamical system. Here, global DDE models were used to analyze 5 min data segments of electrocardiographic (ECG) recordings in order to capture distinguishing features for different heart conditions such as normal heart beat, congestive heart failure, and atrial fibrillation. The number of terms and delays in the model as well as the order of nonlinearity of the model have to be selected that are the most discriminative. The DDE model form that best separates the three classes of data was chosen by exhaustive search up to third order polynomials. Such an approach can provide deep insight into the nature of the data since linear terms of a DDE correspond to the main time-scales in the signal and the nonlinear terms in the DDE are related to nonlinear couplings between the harmonic signal parts. The DDEs were able to detect atrial fibrillation with an accuracy of 72%, congestive heart failure with an accuracy of 88%, and normal heart beat with an accuracy of 97% from 5 min of ECG, a much shorter time interval than required to achieve comparable performance with other methods.

  3. Beta-delayed neutron decay of {sup 33}Na

    Energy Technology Data Exchange (ETDEWEB)

    Radivojevic, Z. E-mail: zoran.radivojevic@phys.jyu.fi; Baumann, P.; Caurier, E.; Cederkaell, J.; Courtin, S.; Dessagne, Ph.; Jokinen, A.; Knipper, A.; Scornet, G.L.G. Le; Lyapin, V.; Miehe, Ch.; Nowacki, F.; Nummela, S.; Oinonen, M.; Poirier, E.; Ramdhane, M.; Trzaska, W.H.; Walter, G.; Aeystoe, J

    2002-04-01

    Beta-delayed neutron decay of {sup 33}Na has been studied using the on-line mass separator ISOLDE. The delayed neutron spectra were measured by time-of-flight technique using fast scintillators. Two main neutron groups at 800(60) and 1020(80) keV were assigned to the {sup 33}Na decay, showing evidence for strong feeding of states at about 4 MeV in {sup 33}Mg. By simultaneous {beta}-{gamma}-n counting the delayed neutron emission probabilities P{sub 1n}=47(6)% and P{sub 2n}=13(3)% were determined. The half-life value for {sup 33}Na, T{sub 1/2}=8.0(3) ms, was measured by three different techniques, one employing identifying gamma transitions and two employing beta and neutron counting.

  4. Beta-delayed proton emission from {sup 20}Mg

    Energy Technology Data Exchange (ETDEWEB)

    Lund, M.V.; Fynbo, H.O.U.; Howard, A.M.; Kirsebom, O.S.; Munch, M.; Riisager, K. [Aarhus University, Department of Physics and Astronomy, Aarhus C (Denmark); Andreyev, A.; Wadsworth, R. [University of York, Department of Physics, York (United Kingdom); Borge, M.J.G. [CSIC, Instituto de Estructura de la Materia, Madrid (Spain); CERN, ISOLDE, PH Department, Geneva 23 (Switzerland); Cederkaell, J. [Lund University, Department of Nuclear Physics, Lund (Sweden); Witte, H. de; Huyse, M.; Duppen, P. van [Instituut voor Kern- en Stralingsfysica, KU-Leuven, Leuven (Belgium); Fraile, L.M.; Vedia, V. [Universidad Complutense de Madrid, CEI Moncloa, Facultad de Ciencias Fisicas, Madrid (Spain); Greenlees, P.T.; Konki, J.; Rahkila, P. [University of Helsinki, Helsinki Institute of Physics, Helsinki (Finland); University of Jyvaeskylae, Department of Physics, Jyvaeskylae (Finland); Harkness-Brennan, L.J.; Judson, D.S.; Page, R.D. [University of Liverpool, Department of Physics, Oliver Lodge Laboratory, Liverpool (United Kingdom); Jonson, B.; Lindberg, S.; Nilsson, T. [Chalmers University of Technology, Department of Physics, Goeteborg (Sweden); Kurcewicz, J.; Madurga, M.; Rapisarda, E. [CERN, ISOLDE, PH Department, Geneva (Switzerland); Lazarus, I.; Pucknell, V. [STFC Daresbury, Daresbury, Warrington (United Kingdom); Lica, R. [CERN, ISOLDE, PH Department, Geneva (Switzerland); ' ' Horia Hulubei' ' National Institute of Physics and Nuclear Engineering, Magurele (Romania); Marginean, N.; Marginean, R.; Mihai, C.; Negret, A.; Pascu, S.; Rotaru, F.; Stanoiu, M.; Turturica, A. [' ' Horia Hulubei' ' National Institute of Physics and Nuclear Engineering, Magurele (Romania); Marroquin, I.; Nacher, E.; Perea, A.; Tengblad, O. [CSIC, Instituto de Estructura de la Materia, Madrid (Spain); Sotty, C. [Instituut voor Kern- en Stralingsfysica, KU-Leuven, Leuven (Belgium); ' ' Horia Hulubei' ' National Institute of Physics and Nuclear Engineering, Magurele (Romania); Warr, N. [Universitaet Koeln, Institut fuer Kernphysik, Koeln (Germany); Collaboration: IDS Collaboration

    2016-10-15

    Beta-delayed proton emission from {sup 20} Mg has been measured at ISOLDE, CERN, with the ISOLDE Decay Station (IDS) setup including both charged-particle and gamma-ray detection capabilities. A total of 27 delayed proton branches were measured including seven so far unobserved. An updated decay scheme, including three new resonances above the proton separation energy in {sup 20}Na and more precise resonance energies, is presented. Beta-decay feeding to two resonances above the Isobaric Analogue State (IAS) in {sup 20}Na is observed. This may allow studies of the 4032.9(2.4) keV resonance in {sup 19}Ne through the beta decay of {sup 20}Mg, which is important for the astrophysically relevant reaction {sup 15}O(α, γ){sup 19}Ne. Beta-delayed protons were used to obtain a more precise value for the half-life of {sup 20}Mg, 91.4(1.0) ms. (orig.)

  5. Recent Advances in Understanding Delayed Photoluminescence in Colloidal Semiconductor Nanocrystals.

    Science.gov (United States)

    Marchioro, Arianna

    2017-02-22

    Colloidal semiconductor nanocrystals display remarkably bright, strongly size-dependent photoluminescence properties. Following photoexcitation of these materials, temporary charge carrier separation can occur where one or both charge carriers are trapped. Charge detrapping can reform the emissive state on long time scales up to seconds, causing delayed luminescence. This delayed luminescence has not yet been thoroughly explored, and appears to be closely associated with a phenomenon observed at the single particle level, i.e. photoluminescence intermittency (blinking). Here, some of our recent work on the delayed luminescence properties of nanocrystals of different chemical composition is reviewed. These results provide insight into the mechanism of carrier detrapping, and are discussed in the context of photoluminescence blinking.

  6. Delay Independent Criterion for Multiple Time-delay Systems

    Science.gov (United States)

    Chang, C. J.; Liu, K. F. R.; Yeh, K.; Chen, C. W.; Chung, P. Y.

    Based on the fuzzy Lyapunov method, this work addresses the stability conditions for nonlinear systems with multiple time delays to ensure the stability of building structure control systems. The delay independent conditions are derived via the traditional Lyapunov and fuzzy Lyapunov methods for multiple time-delay systems as approximated by the Tagagi-Sugeno (T-S) fuzzy model. The fuzzy Lyapunov function is defined as a fuzzy blending of quadratic Lyapunov functions. A parallel distributed compensation (PDC) scheme is utilized to construct a global fuzzy logic control (FLC) by blending all linear local state feedback controllers in the controller design procedure. Furthermore, the H infinity performance and robustness of the design for modeling errors also need to be considered in the stability conditions.

  7. Working with Separation

    Science.gov (United States)

    Krugman, Dorothy C.

    1971-01-01

    Discusses the role of the caseworker in providing support to children experiencing separation from their families and emphasizes the need to recognize that there are differences between those separation experiences dictated by the needs of children and those dictated by arbitrary or noncasework factors. (AJ)

  8. Separation anxiety disorder

    NARCIS (Netherlands)

    Nauta, M.H.; Emmelkamp, P.M.G.; Sturmey, P.; Hersen, M.

    2012-01-01

    Separation anxiety disorder (SAD) is the only anxiety disorder that is specific to childhood; however, SAD has hardly ever been addressed as a separate disorder in clinical trials investigating treatment outcome. So far, only parent training has been developed specifically for SAD. This particular t

  9. Social Separation in Monkeys.

    Science.gov (United States)

    Mineka, Susan; Suomi, Stephen J.

    1978-01-01

    Reviews phenomena associated with social separation from attachment objects in nonhuman primates. Evaluates four theoretical treatments of separation in light of existing data: Bowlby's attachment-object-loss theory, Kaufman's conservation-withdrawal theory, Seligman's learned helplessness theory, and Solomon and Corbit's opponent-process theory.…

  10. Nonterminal Separating Macro Grammars

    NARCIS (Netherlands)

    Hogendorp, Jan Anne; Asveld, P.R.J.; Nijholt, A.; Verbeek, Leo A.M.

    1987-01-01

    We extend the concept of nonterminal separating (or NTS) context-free grammar to nonterminal separating $m$-macro grammar where the mode of derivation $m$ is equal to "unrestricted". "outside-in' or "inside-out". Then we show some (partial) characterization results for these NTS $m$-macro grammars.

  11. Spiral microfluidic nanoparticle separators

    Science.gov (United States)

    Bhagat, Ali Asgar S.; Kuntaegowdanahalli, Sathyakumar S.; Dionysiou, Dionysios D.; Papautsky, Ian

    2008-02-01

    Nanoparticles have potential applications in many areas such as consumer products, health care, electronics, energy and other industries. As the use of nanoparticles in manufacturing increases, we anticipate a growing need to detect and measure particles of nanometer scale dimensions in fluids to control emissions of possible toxic nanoparticles. At present most particle separation techniques are based on membrane assisted filtering schemes. Unfortunately their efficiency is limited by the membrane pore size, making them inefficient for separating a wide range of sizes. In this paper, we propose a passive spiral microfluidic geometry for momentum-based particle separations. The proposed design is versatile and is capable of separating particulate mixtures over a wide dynamic range and we expect it will enable a variety of environmental, medical, or manufacturing applications that involve rapid separation of nanoparticles in real-world samples with a wide range of particle components.

  12. 长隧道带蒂包皮内板尿道成形术治疗阴茎体型尿道下裂的疗效分析%Long channel technique with pedicle inner preputial flap urethroplasty for middle hypospadias repair

    Institute of Scientific and Technical Information of China (English)

    苏诚; 杨天佑; 张志崇; 梁奇峰; 徐晔青; 梅骅

    2011-01-01

    目的 探讨长隧道带蒂包皮内板尿道成形术治疗阴茎体型尿道下裂的疗效. 方法 2007年9月至2010年4月收治阴茎体型尿道下裂患儿28例,年龄1.5 ~6.0岁,平均2.0岁.均行长隧道带蒂包皮内板尿道成形术.尿道开口均位于阴茎体部,距离阴茎头顶端16 ~ 37 mm,平均25immn;分离尿道及纠正阴茎下曲后尿道缺损30 ~ 42 mm,平均38 mm.手术要点:沿尿道开口环形切开阴茎皮肤,分离至尿道板,横断尿道板,沿尿道板与海绵体之间分离隧道至阴茎头正中,隧道长度26~38 mm,平均33 mm.尿道开口至阴茎头之间全程由隧道贯通,尽量保持阴茎腹侧皮肤与组织完整,取带蒂包皮内板制作新尿道,将新尿道通过阴茎侧方深筋膜下通道转移至腹侧隧道进行吻合.术中人工勃起试验证实合并轻度阴茎下曲13例,无明显阴茎下曲15例. 结果 28例均一期修复成功,手术时间50~70 min,平均55min.随访时间6~31个月,平均20个月.28例患儿均排尿通畅,尿线粗直.尿道呈矢状开口于阴茎头正中,阴茎下曲纠正满意,外观好,未发生尿瘘或狭窄. 结论 长隧道带蒂包皮内板尿道成形术适用于无或合并轻度阴茎下曲的阴茎体型尿道下裂,尤其适合年龄小或阴茎体细小患儿,手术简单,效果好,外观满意.%Objective To investigate the indications and results of long channel technique with pedicle inner preputial flap urethroplasty for middle hypospadias repair. Methods During September 2007 to April 2010,28 cases of middle hypospadias were include in this study.The average age was 2.0 years (1.5 -6.0 years).The orifice of urethra was opened in the shaft of penis,and the distance between the urethral meatus and the center of glans was 25 mm ( 16 - 37 mm).A pars-meatus skin incision was made,which was dissected deep to the urethral plate.The urethral plate was transected,and a long channel between the urethral plate and the corpora cavernosa was

  13. 49 CFR 236.563 - Delay time.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Delay time. 236.563 Section 236.563 Transportation... Cab Signal Systems Rules and Instructions; Locomotives § 236.563 Delay time. Delay time of automatic... requirements of § 236.24 shall take into consideration the delay time....

  14. Stochastic modelling of train delays and delay propagation in stations

    NARCIS (Netherlands)

    Yuan, J.

    2006-01-01

    A trade-off exists between efficiently utilizing the capacity of railway networks and improving the reliability and punctuality of train operations. This dissertation presents a new analytical probability model based on blocking time theory which estimates the knock-on delays of trains caused by

  15. Delaying vortex breakdown by waves

    Science.gov (United States)

    Yao, M. F.; Jiang, L. B.; Wu, J. Z.; Ma, H. Y.; Pan, J. Y.

    1989-03-01

    The effect of spiral waves on delaying vortex breakdown in a tube is studied experimentally and theoretically. When a harmonic oscillation was imposed on one of guiding vanes in the tube, the breakdown was observed to be postponed appreciately. According to the generalized Lagrangian mean theory, proper forcing spiral waves may produce an additional streaming momentum, of which the effect is favorable and similar to an axial suction at downstream end. The delayed breakdown position is further predicted by using nonlinear wave theory. Qualitative agreement between theory and experiment is obtained, and experimental comparison of the effects due to forcing spiral wave and axial suction is made.

  16. Delay equations and radiation damping

    Science.gov (United States)

    Chicone, C.; Kopeikin, S. M.; Mashhoon, B.; Retzloff, D. G.

    2001-06-01

    Starting from delay equations that model field retardation effects, we study the origin of runaway modes that appear in the solutions of the classical equations of motion involving the radiation reaction force. When retardation effects are small, we argue that the physically significant solutions belong to the so-called slow manifold of the system and we identify this invariant manifold with the attractor in the state space of the delay equation. We demonstrate via an example that when retardation effects are no longer small, the motion could exhibit bifurcation phenomena that are not contained in the local equations of motion.

  17. Feedback delays eliminate auditory-motor learning in speech production.

    Science.gov (United States)

    Max, Ludo; Maffett, Derek G

    2015-03-30

    Neurologically healthy individuals use sensory feedback to alter future movements by updating internal models of the effector system and environment. For example, when visual feedback about limb movements or auditory feedback about speech movements is experimentally perturbed, the planning of subsequent movements is adjusted - i.e., sensorimotor adaptation occurs. A separate line of studies has demonstrated that experimentally delaying the sensory consequences of limb movements causes the sensory input to be attributed to external sources rather than to one's own actions. Yet similar feedback delays have remarkably little effect on visuo-motor adaptation (although the rate of learning varies, the amount of adaptation is only moderately affected with delays of 100-200ms, and adaptation still occurs even with a delay as long as 5000ms). Thus, limb motor learning remains largely intact even in conditions where error assignment favors external factors. Here, we show a fundamentally different result for sensorimotor control of speech articulation: auditory-motor adaptation to formant-shifted feedback is completely eliminated with delays of 100ms or more. Thus, for speech motor learning, real-time auditory feedback is critical. This novel finding informs theoretical models of human motor control in general and speech motor control in particular, and it has direct implications for the application of motor learning principles in the habilitation and rehabilitation of individuals with various sensorimotor speech disorders. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. Time-domain nature of group delay

    Institute of Scientific and Technical Information of China (English)

    王建武; 冯正和

    2015-01-01

    The characteristic of group delay is analyzed based on an electronic circuit, and its time-domain nature is studied with time-domain simulation and experiment. The time-domain simulations and experimental results show that group delay is the delay of the energy center of the amplitude-modulated pulse, rather than the propagation delay of the electromagnetic field. As group velocity originates from the definition of group delay and group delay is different from the propagation delay, the superluminality or negativity of group velocity does not mean the superluminal or negative propagation of the electromagnetic field.

  19. Radiochemical separation of Cobalt

    NARCIS (Netherlands)

    Erkelens, P.C. van

    1961-01-01

    A method is described for the radiochemical separation of cobalt based on the extraordinary stability of cobalt diethyldithiocarbamate. Interferences are few; only very small amounts of zinc and iron accompany cobalt, which is important in neutron-activation analysis.

  20. On Separate Universes

    CERN Document Server

    Dai, Liang; Schmidt, Fabian

    2015-01-01

    The separate universe conjecture states that in General Relativity a density perturbation behaves locally (i.e. on scales much smaller than the wavelength of the mode) as a separate universe with different background density and curvature. We prove this conjecture for a spherical compensated tophat density perturbation of arbitrary amplitude and radius in $\\Lambda$CDM. We then use Conformal Fermi Coordinates to generalize this result to scalar perturbations of arbitrary configuration and scale in a general cosmology with a mixture of fluids, but to linear order in perturbations. In this case, the separate universe conjecture holds for the isotropic part of the perturbations. The anisotropic part on the other hand is exactly captured by a tidal field in the Newtonian form. We show that the separate universe picture is restricted to scales larger than the sound horizons of all fluid components. We then derive an expression for the locally measured matter bispectrum induced by a long-wavelength mode of arbitrary...

  1. Electroextraction separation of dyestuffs

    Energy Technology Data Exchange (ETDEWEB)

    Luo, G.S.; Yu, M.J.; Jiang, W.B.; Zhu, S.L.; Dai, Y.Y. [Tsinghua Univ., Beijing (China). Dept. of Chemical Engineering

    1999-03-01

    Electroseparation technologies have prospects for significant growth well into the next century. Electroextraction, a coupled separation technique of solvent extraction with electrophoresis, was used to remove dyestuffs from their aqueous stream. A study on the characteristics of the separation technique was carried out with n-butanol/acid-chrom blue K/water and n-butanol/methyl blue/water as working systems. A continuous separation equipment was designed and sued in this work. The influences of two-phase flow, field strength, and concentration of the feed on the recovery of solute were studied. The results showed that much higher recovery of solute with less solvent consumption could be achieved by using this technique to remove dyes from their aqueous streams, especially for the separation of the dilute solution. When the field strength is increased, the recovery and mass flux increase. When the feed flow rate and the initial solute concentration are increased, the recovery decreases and the mass flux increases.

  2. Shoulder separation - aftercare

    Science.gov (United States)

    ... and top of your shoulder blade A severe shoulder separation You may need surgery right away if you have: Numbness in your fingers Cold fingers Muscle weakness in your arm Severe deformity of the joint

  3. Radiochemical separation of Cobalt

    NARCIS (Netherlands)

    Erkelens, P.C. van

    1961-01-01

    A method is described for the radiochemical separation of cobalt based on the extraordinary stability of cobalt diethyldithiocarbamate. Interferences are few; only very small amounts of zinc and iron accompany cobalt, which is important in neutron-activation analysis.

  4. Safe Separators for Treewidth

    NARCIS (Netherlands)

    Bodlaender, H.L.; Koster, A.M.C.A.

    2003-01-01

    A set of vertices S Í V is called a safe separator for treewidth, if S is a separator of G, and the treewidth of G equals the maximum of the treewidth over all connected components W of G - S of the graph, obtained by making S a clique in the subgraph of G, induced by W È S. We show that such safe s

  5. Hydrogen separation process

    Science.gov (United States)

    Mundschau, Michael [Longmont, CO; Xie, Xiaobing [Foster City, CA; Evenson, IV, Carl; Grimmer, Paul [Longmont, CO; Wright, Harold [Longmont, CO

    2011-05-24

    A method for separating a hydrogen-rich product stream from a feed stream comprising hydrogen and at least one carbon-containing gas, comprising feeding the feed stream, at an inlet pressure greater than atmospheric pressure and a temperature greater than 200.degree. C., to a hydrogen separation membrane system comprising a membrane that is selectively permeable to hydrogen, and producing a hydrogen-rich permeate product stream on the permeate side of the membrane and a carbon dioxide-rich product raffinate stream on the raffinate side of the membrane. A method for separating a hydrogen-rich product stream from a feed stream comprising hydrogen and at least one carbon-containing gas, comprising feeding the feed stream, at an inlet pressure greater than atmospheric pressure and a temperature greater than 200.degree. C., to an integrated water gas shift/hydrogen separation membrane system wherein the hydrogen separation membrane system comprises a membrane that is selectively permeable to hydrogen, and producing a hydrogen-rich permeate product stream on the permeate side of the membrane and a carbon dioxide-rich product raffinate stream on the raffinate side of the membrane. A method for pretreating a membrane, comprising: heating the membrane to a desired operating temperature and desired feed pressure in a flow of inert gas for a sufficient time to cause the membrane to mechanically deform; decreasing the feed pressure to approximately ambient pressure; and optionally, flowing an oxidizing agent across the membrane before, during, or after deformation of the membrane. A method of supporting a hydrogen separation membrane system comprising selecting a hydrogen separation membrane system comprising one or more catalyst outer layers deposited on a hydrogen transport membrane layer and sealing the hydrogen separation membrane system to a porous support.

  6. Separation techniques: Chromatography

    OpenAIRE

    Coskun, Ozlem

    2016-01-01

    Chromatography is an important biophysical technique that enables the separation, identification, and purification of the components of a mixture for qualitative and quantitative analysis. Proteins can be purified based on characteristics such as size and shape, total charge, hydrophobic groups present on the surface, and binding capacity with the stationary phase. Four separation techniques based on molecular characteristics and interaction type use mechanisms of ion exchange, surface adsorp...

  7. Distal humeral epiphyseal separation.

    Science.gov (United States)

    Moucha, Calin S; Mason, Dan E

    2003-10-01

    Distal humeral epiphyseal separation is an uncommon injury that is often misdiagnosed upon initial presentation. To make a timely, correct diagnosis, the treating physician must have a thorough understanding of basic anatomical relationships and an awareness of the existence of this injury. This is a case of a child who sustained a separation of the distal humeral epiphysis, as well as multiple other bony injuries, secondary to child abuse.

  8. Diagnostic Delay in Rheumatoid Arthritis

    DEFF Research Database (Denmark)

    Mølbaek, Karen; Hørslev-Petersen, Kim; Primdahl, Jette

    2016-01-01

    BACKGROUND: To prevent joint damage among patients with rheumatoid arthritis (RA), there is a need to minimize delays from the onset of symptoms until the initiation of appropriate therapy. The present study explored the factors that have an impact on the time it takes for Danish patients with RA...

  9. Livermore blasted for project delay

    CERN Multimedia

    1999-01-01

    In a 12 page report issued last week, a review committee set up by the University of California has concluded that mismanagement and poor planning are to blame for significant cost overruns and delays in the construction of NIF, the worlds largest laser (1 page).

  10. Providing delay guarantees in Bluetooth

    NARCIS (Netherlands)

    Ait Yaiz, R.; Heijenk, Gerhard J.; Titsworth, F.

    2003-01-01

    Bluetooth polling, also referred to as Bluetooth MAC scheduling or intra-piconet scheduling, is the mechanism that schedules the traffic between the participants in a Bluetooth network. Hence, this mechanism is highly determining with respect to the delay packets experience in a Bluetooth network.

  11. Deconstructing delayed posttraumatic stress disorder

    NARCIS (Netherlands)

    Smid, G.E.

    2011-01-01

    According to the Diagnostic and Statistical Manual of Mental Disorders, delayed posttraumatic stress disorder (PTSD) must be diagnosed in individuals fulfilling criteria for PTSD if the onset of symptoms is at least six months after the trauma. The purpose of this thesis was to establish the prevale

  12. Advanced optical delay line demonstrator

    NARCIS (Netherlands)

    Dool, T.C. van den; Kamphues, F.G.; Fouss, B.; Henrioulle, K.; Hogenhuis, H.

    2004-01-01

    TNO TPD, in cooperation with Micromega-Dynamics and Dutch Space, has designed an advanced Optical Delay Line (ODL) for use in future ground based and space interferometry missions. The work is performed under NIVR contract in preparation for GENIE and DARWIN. Using the ESO PRIMA DDL requirements as

  13. Providing Delay Guarantees in Bluetooth

    NARCIS (Netherlands)

    Ait Yaiz, Rachid; Heijenk, Geert; Titsworth, F.

    2003-01-01

    Bluetooth polling, also referred to as Bluetooth MAC scheduling or intra-piconet scheduling, is the mechanism that schedules the traffic between the participants in a Bluetooth network. Hence, this mechanism is highly determining with respect to the delay packets experience in a Bluetooth network. I

  14. Separation attenuation in swept shock wave-boundary-layer interactions using different microvortex generator geometries

    Science.gov (United States)

    Martis, R. R.; Misra, A.

    2017-03-01

    A numerical study is conducted to determine the effectiveness of six different microvortex generator geometries in controlling swept shock wave/boundary-layer interactions. The geometries considered are base ramp, base ramp with declining angle of 45°, blunt ramp, split ramp, thick vanes, and ramped vanes. Microvortex generators with a gap were found to be better suited for delaying the separation. Thick vanes showed the largest delay in separation among the devices studied.

  15. Separation attenuation in swept shock wave-boundary-layer interactions using different microvortex generator geometries

    Science.gov (United States)

    Martis, R. R.; Misra, A.

    2017-09-01

    A numerical study is conducted to determine the effectiveness of six different microvortex generator geometries in controlling swept shock wave/boundary-layer interactions. The geometries considered are base ramp, base ramp with declining angle of 45°, blunt ramp, split ramp, thick vanes, and ramped vanes. Microvortex generators with a gap were found to be better suited for delaying the separation. Thick vanes showed the largest delay in separation among the devices studied.

  16. Time Delay Circuits: A Quality Criterion for Delay Variations versus Frequency

    NARCIS (Netherlands)

    Garakoui, Seyed Kasra; Klumperink, Eric A.M.; Nauta, Bram; Vliet, van Frank E.

    2010-01-01

    This paper shows that the group delay of a delay circuit does not give sufficient information to predict the delay vs. frequency. A new criterion (fϕ=0) is proposed that characterizes the delay variations over a specified frequency range. The mathematical derivation of fϕ=0 for a single delay block

  17. THE ALL-DELAY STABILITY OF DEGENERATE DIFFERENTIAL SYSTEMS WITH DELAY

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this paper,the all-delay stability of degenerate differential systems with delay is discussed.We come up with some new criteria for evaluating the all-delay stability of degenerate differential systems with delay and degenerate neutral differential systems with delay.Also,we give an example to illustrate the main results.

  18. Streaming effect of wall oscillation to boundary layer separation

    Science.gov (United States)

    Wu, X. H.; Wu, J. Z.; Wu, J. M.

    1991-01-01

    This paper presents a preliminary theoretical result on the time averaged streaming effect of local forcing excitation to the boundary layer separation from smooth surface. The problem is formulated as a periodic disturbance to a basic steady breakaway separating flow, for which the data are taken from a numerical triple-deck solution. The ratio of Strouhal number St and Reynolds number Re plays an important role, both being assumed sufficiently high. The analytical and numerical results show that this streaming effect is quite strong at proper values of St/Re exp 1/4, which may delay or even suppress the separation.

  19. Streaming effect of wall oscillation to boundary layer separation

    Science.gov (United States)

    Wu, X. H.; Wu, J. Z.; Wu, J. M.

    1991-01-01

    This paper presents a preliminary theoretical result on the time averaged streaming effect of local forcing excitation to the boundary layer separation from smooth surface. The problem is formulated as a periodic disturbance to a basic steady breakaway separating flow, for which the data are taken from a numerical triple-deck solution. The ratio of Strouhal number St and Reynolds number Re plays an important role, both being assumed sufficiently high. The analytical and numerical results show that this streaming effect is quite strong at proper values of St/Re exp 1/4, which may delay or even suppress the separation.

  20. Organic Separation Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Russell, Renee L.; Rinehart, Donald E.; Peterson, Reid A.

    2014-09-22

    Separable organics have been defined as “those organic compounds of very limited solubility in the bulk waste and that can form a separate liquid phase or layer” (Smalley and Nguyen 2013), and result from three main solvent extraction processes: U Plant Uranium Recovery Process, B Plant Waste Fractionation Process, and Plutonium Uranium Extraction (PUREX) Process. The primary organic solvents associated with tank solids are TBP, D2EHPA, and NPH. There is concern that, while this organic material is bound to the sludge particles as it is stored in the tanks, waste feed delivery activities, specifically transfer pump and mixer pump operations, could cause the organics to form a separated layer in the tank farms feed tank. Therefore, Washington River Protection Solutions (WRPS) is experimentally evaluating the potential of organic solvents separating from the tank solids (sludge) during waste feed delivery activities, specifically the waste mixing and transfer processes. Given the Hanford Tank Waste Treatment and Immobilization Plant (WTP) waste acceptance criteria per the Waste Feed Acceptance Criteria document (24590-WTP-RPT-MGT-11-014) that there is to be “no visible layer” of separable organics in the waste feed, this would result in the batch being unacceptable to transfer to WTP. This study is of particular importance to WRPS because of these WTP requirements.

  1. Gulf stream separation dynamics

    Science.gov (United States)

    Schoonover, Joseph

    Climate models currently struggle with the more traditional, coarse ( O(100 km) ) representation of the ocean. In these coarse ocean simulations, western boundary currents are notoriously difficult to model accurately. The modeled Gulf Stream is typically seen exhibiting a mean pathway that is north of observations, and is linked to a warm sea-surface temperature bias in the Mid-Atlantic Bight. Although increased resolution ( O(10 km) ) improves the modeled Gulf Stream position, there is no clean recipe for obtaining the proper pathway. The 70 year history of literature on the Gulf Stream separation suggests that we have not reached a resolution on the dynamics that control the current's pathway just south of the Mid-Atlantic Bight. Without a concrete knowledge on the separation dynamics, we cannot provide a clean recipe for accurately modeling the Gulf Stream at increased resolutions. Further, any reliable parameterization that yields a realistic Gulf Stream path must express the proper physics of separation. The goal of this dissertation is to determine what controls the Gulf Stream separation. To do so, we examine the results of a model intercomparison study and a set of numerical regional terraforming experiments. It is argued that the separation is governed by local dynamics that are most sensitive to the steepening of the continental shelf, consistent with the topographic wave arrest hypothesis of Stern (1998). A linear extension of Stern's theory is provided, which illustrates that wave arrest is possible for a continuously stratified fluid.

  2. Separably injective Banach spaces

    CERN Document Server

    Avilés, Antonio; Castillo, Jesús M F; González, Manuel; Moreno, Yolanda

    2016-01-01

    This monograph contains a detailed exposition of the up-to-date theory of separably injective spaces: new and old results are put into perspective with concrete examples (such as l∞/c0 and C(K) spaces, where K is a finite height compact space or an F-space, ultrapowers of L∞ spaces and spaces of universal disposition). It is no exaggeration to say that the theory of separably injective Banach spaces is strikingly different from that of injective spaces. For instance, separably injective Banach spaces are not necessarily isometric to, or complemented subspaces of, spaces of continuous functions on a compact space. Moreover, in contrast to the scarcity of examples and general results concerning injective spaces, we know of many different types of separably injective spaces and there is a rich theory around them. The monograph is completed with a preparatory chapter on injective spaces, a chapter on higher cardinal versions of separable injectivity and a lively discussion of open problems and further lines o...

  3. Mass Separation by Metamaterials.

    Science.gov (United States)

    Restrepo-Flórez, Juan Manuel; Maldovan, Martin

    2016-02-25

    Being able to manipulate mass flow is critically important in a variety of physical processes in chemical and biomolecular science. For example, separation and catalytic systems, which requires precise control of mass diffusion, are crucial in the manufacturing of chemicals, crystal growth of semiconductors, waste recovery of biological solutes or chemicals, and production of artificial kidneys. Coordinate transformations and metamaterials are powerful methods to achieve precise manipulation of molecular diffusion. Here, we introduce a novel approach to obtain mass separation based on metamaterials that can sort chemical and biomolecular species by cloaking one compound while concentrating the other. A design strategy to realize such metamaterial using homogeneous isotropic materials is proposed. We present a practical case where a mixture of oxygen and nitrogen is manipulated using a metamaterial that cloaks nitrogen and concentrates oxygen. This work lays the foundation for molecular mass separation in biophysical and chemical systems through metamaterial devices.

  4. Phaco slice and separate.

    Science.gov (United States)

    Arshinoff, S A

    1999-04-01

    Phaco slice and separate retains the advantages of the chopping techniques of Nagahara, Koch, and Fukasaku but replaces chopping or snapping with slicing across the center of the phaco-tip-stabilized nucleus using a Nagahara chopper and then repositioning the chopper to optimally separate the divided lens halves. As the lens is rotated in the capsular bag, small pieces of the nuclear pie are sliced off, separated, emulsified, and aspirated. Emulsification and aspiration can alternatively be left until most or all the slices have been made. This technique works with a broader range of lens densities than other chopping techniques and uses no sculpting and very little phaco time. The phaco time required for this technique is relatively independent of nuclear density compared with a sculpting technique.

  5. Membrane separation of hydrocarbons

    Science.gov (United States)

    Chang, Y. Alice; Kulkarni, Sudhir S.; Funk, Edward W.

    1986-01-01

    Mixtures of heavy oils and light hydrocarbons may be separated by passing the mixture through a polymeric membrane. The membrane which is utilized to effect the separation comprises a polymer which is capable of maintaining its integrity in the presence of hydrocarbon compounds and which has been modified by being subjected to the action of a sulfonating agent. Sulfonating agents which may be employed will include fuming sulfuric acid, chlorosulfonic acid, sulfur trioxide, etc., the surface or bulk modified polymer will contain a degree of sulfonation ranging from about 15 to about 50%. The separation process is effected at temperatures ranging from about ambient to about 100.degree. C. and pressures ranging from about 50 to about 1000 psig.

  6. Delay of Vehicle Motion in Traffic Dynamics

    CERN Document Server

    Bando, M; Nakanishi, K; Nakayama, A; Bando, Masako; Hasebe, Katsuya; Nakanishi, Ken; Nakayama, Akihiro

    1996-01-01

    We demonstrate that in Optimal Velocity Model (OVM) delay times of vehicles coming from the dynamical equation of motion of OVM almost explain the order of delay times observed in actual traffic flows without introducing explicit delay times. Delay times in various cases are estimated: the case of a leader vehicle and its follower, a queue of vehicles controlled by traffic lights and many-vehicle case of highway traffic flow. The remarkable result is that in most of the situation for which we can make a reasonable definition of a delay time, the obtained delay time is of order 1 second.

  7. Gender and individual information coded by insect pheromone analogs in the preputial glands in male brandt's voles Lasiopodomys brandtii%雄性布氏田鼠包皮腺中的昆虫信息素类似物编码的性别和个体信息

    Institute of Scientific and Technical Information of China (English)

    张健旭; 赵成华; 饶小平; 王大伟; 刘晓辉; 秦小薇; 张知彬

    2007-01-01

    我们利用二氯甲烷抽提和气质联用(GC-MS)比较分析了正常和阉割布氏田鼠的包皮腺分泌物(PGS)成分.我们检测到33个成分,它们几乎在所有的被测布氏田鼠都存在,其中27个成分以前报道为昆虫的信息素组分.睾丸切除不能使任何一个成分完全消失,但是显著降低了10个首先从GC-MS流失出的小分子成分,即7个饱和与不饱和的乙酸酯,一个饱和六酸酯和两个饱和八酸酯, 其中,包括PGS含量最高的成分E,E-法尼醇乙酸酯.因此,可以认为这些受睾丸调节的成分为雄性信息素的候选成分.对雌鼠的嗅觉双项选择测定说明低浓度的PGS和法尼醇乙酸酯水溶液对雌性有吸引作用,而高浓度时都具有趋避作用.这说明PGS具有剂量依赖的性吸引作用,法尼醇乙酸酯是一种剂量依赖的雄性信息素.进一步的数量比较说明,所有检测到成分的百分组成在个体间表现出巨大的个体变异,说明PGS的成分有个体的特异性,可能传递个体的嗅觉信息.%We analyzed the volatile composition of dichloromethane extracts of preputial glandular secretions (PGS) from intact and castrated male Brandt's voles Lasiopodomys brandtii by using gas chromatography-mass spectrometry (GC-MS).Thirty-three volatile compounds were detected and were present in nearly all scent donors; 27 had previously been reported as insect pheromone components. Castration did not eliminate any compounds; however, it significantly suppressed the relative quantity of ten early-eluting, low molecular weight components. These included seven saturated and unsaturated acetates, one hexanoate, and two saturated octanoates. In particular, E,E-Farnesyl acetate (FA) was the most abundant compound in the PGS. We suggest that FA and other components might be candidates for male-produced pheromones. Two-choice behavioral assays of females revealed that low concentrations of raw PGS (0.056%) and E,E-farnesyl acetate (FA) (5 parts

  8. Gas separation membranes

    Science.gov (United States)

    Schell, William J.

    1979-01-01

    A dry, fabric supported, polymeric gas separation membrane, such as cellulose acetate, is prepared by casting a solution of the polymer onto a shrinkable fabric preferably formed of synthetic polymers such as polyester or polyamide filaments before washing, stretching or calendering (so called griege goods). The supported membrane is then subjected to gelling, annealing, and drying by solvent exchange. During the processing steps, both the fabric support and the membrane shrink a preselected, controlled amount which prevents curling, wrinkling or cracking of the membrane in flat form or when spirally wound into a gas separation element.

  9. Separation membrane development

    Energy Technology Data Exchange (ETDEWEB)

    Lee, M.W. [Savannah River Technology Center, Aiken, SC (United States)

    1998-08-01

    A ceramic membrane has been developed to separate hydrogen from other gases. The method used is a sol-gel process. A thin layer of dense ceramic material is coated on a coarse ceramic filter substrate. The pore size distribution in the thin layer is controlled by a densification of the coating materials by heat treatment. The membrane has been tested by permeation measurement of the hydrogen and other gases. Selectivity of the membrane has been achieved to separate hydrogen from carbon monoxide. The permeation rate of hydrogen through the ceramic membrane was about 20 times larger than Pd-Ag membrane.

  10. Separation techniques: Chromatography

    Science.gov (United States)

    Coskun, Ozlem

    2016-01-01

    Chromatography is an important biophysical technique that enables the separation, identification, and purification of the components of a mixture for qualitative and quantitative analysis. Proteins can be purified based on characteristics such as size and shape, total charge, hydrophobic groups present on the surface, and binding capacity with the stationary phase. Four separation techniques based on molecular characteristics and interaction type use mechanisms of ion exchange, surface adsorption, partition, and size exclusion. Other chromatography techniques are based on the stationary bed, including column, thin layer, and paper chromatography. Column chromatography is one of the most common methods of protein purification. PMID:28058406

  11. Learning Isometric Separation Maps

    CERN Document Server

    Vasiloglou, Nikolaos; Anderson, David V

    2008-01-01

    Maximum Variance Unfolding (MVU) and its variants have been very successful in embedding data-manifolds in lower dimensionality spaces, often revealing the true intrinsic dimensions. In this paper we show how to also incorporate supervised class information into an MVU-like method without breaking its convexity. We call this method the Isometric Separation Map and we show that the resulting kernel matrix can be used for a binary/multiclass Support Vector Machine in a semi-supervised (transductive) framework. We also show that the method always finds a kernel matrix that linearly separates the training data exactly without projecting them in infinite dimensional spaces.

  12. Separators for electrochemical cells

    Science.gov (United States)

    Carlson, Steven Allen; Anakor, Ifenna Kingsley

    2014-11-11

    Provided are separators for use in an electrochemical cell comprising (a) an inorganic oxide and (b) an organic polymer, wherein the inorganic oxide comprises organic substituents. Preferably, the inorganic oxide comprises an hydrated aluminum oxide of the formula Al.sub.2O.sub.3.xH.sub.2O, wherein x is less than 1.0, and wherein the hydrated aluminum oxide comprises organic substituents, preferably comprising a reaction product of a multifunctional monomer and/or organic carbonate with an aluminum oxide, such as pseudo-boehmite and an aluminum oxide. Also provided are electrochemical cells comprising such separators.

  13. Delay locked loop integrated circuit.

    Energy Technology Data Exchange (ETDEWEB)

    Brocato, Robert Wesley

    2007-10-01

    This report gives a description of the development of a Delay Locked Loop (DLL) integrated circuit (IC). The DLL was developed and tested as a stand-alone IC test chip to be integrated into a larger application specific integrated circuit (ASIC), the Quadrature Digital Waveform Synthesizer (QDWS). The purpose of the DLL is to provide a digitally programmable delay to enable synchronization between an internal system clock and external peripherals with unknown clock skew. The DLL was designed and fabricated in the IBM 8RF process, a 0.13 {micro}m CMOS process. It was designed to operate with a 300MHz clock and has been tested up to 500MHz.

  14. Minimum Delay Moving Object Detection

    KAUST Repository

    Lao, Dong

    2017-01-08

    We present a general framework and method for detection of an object in a video based on apparent motion. The object moves relative to background motion at some unknown time in the video, and the goal is to detect and segment the object as soon it moves in an online manner. Due to unreliability of motion between frames, more than two frames are needed to reliably detect the object. Our method is designed to detect the object(s) with minimum delay, i.e., frames after the object moves, constraining the false alarms. Experiments on a new extensive dataset for moving object detection show that our method achieves less delay for all false alarm constraints than existing state-of-the-art.

  15. Time delay and distance measurement

    Science.gov (United States)

    Abshire, James B. (Inventor); Sun, Xiaoli (Inventor)

    2011-01-01

    A method for measuring time delay and distance may include providing an electromagnetic radiation carrier frequency and modulating one or more of amplitude, phase, frequency, polarization, and pointing angle of the carrier frequency with a return to zero (RZ) pseudo random noise (PN) code. The RZ PN code may have a constant bit period and a pulse duration that is less than the bit period. A receiver may detect the electromagnetic radiation and calculate the scattering profile versus time (or range) by computing a cross correlation function between the recorded received signal and a three-state RZ PN code kernel in the receiver. The method also may be used for pulse delay time (i.e., PPM) communications.

  16. Air congestion delay: a review

    Directory of Open Access Journals (Sweden)

    Daniel Alberto Pamplona

    2016-04-01

    Full Text Available This article is a literature review of the air congestion delay and its costs. Air congestion is a worldwide problem. Its existence brings costs for airlines and discomfort for passengers. With the increasing demand for air transport, the study of air congestion has attracted the attention of many researchers around the world. The cause for the delays is erroneously attributed only to the lack of infrastructure investments. The literature review shows that other factors such as population growth, increasing standards of living, lack of operational planning and environmental issues exercise decisive influence. Several studies have been conducted in order to analyze and propose solutions to this problem that affects society as a whole.

  17. Single-Step Tunable Group Delay Phaser for Real-Time Spectrum Sniffing

    CERN Document Server

    Guo, Tongfeng; Chen, Yifan; Wang, Rui; Caloz, Christophe

    2015-01-01

    This paper presents a single-step tunable group delay phaser for spectrum sniffing. This device may be seen as a "time filter", where frequencies are suppressed by time separation rather than by spectral attenuation. Compared to its multiple-step counterpart, this phaser features higher processing resolution, greater simplicity, lower loss and better channel equalization, due to the smaller and channel-independent group delay swing. A three-channel example is provided for illustration.

  18. Teriparatide Induced Delayed Persistent Hypercalcemia

    Directory of Open Access Journals (Sweden)

    Nirosshan Thiruchelvam

    2014-01-01

    Full Text Available Teriparatide, a recombinant PTH, is an anabolic treatment for osteoporosis that increases bone density. Transient hypercalcemia is a reported side effect of teriparatide that is seen few hours following administration of teriparatide and resolves usually within 16 hours of drug administration. Persistent hypercalcemia, although not observed in clinical trials, is rarely reported. The current case describes a rare complication of teriparatide induced delayed persistent hypercalcemia.

  19. Six Channel Digital Delay Generator

    Science.gov (United States)

    1980-01-01

    Historically, delays were generated by R-C networks that fired thyratrons to provide the re- quired output pulses. Because of severe electrical interference...instruction manual. The system clock was an M. F. electronics model 5401-1 in a printed circuit mounting package. This particular model has a 10 MHz...constructed in-house to provide the high voltages required to trip flash x-ray systems and thyratron controlled firing units. Details of this circuit are

  20. Assembly delay line pulse generators

    CERN Document Server

    1971-01-01

    Assembly of six of the ten delay line pulse generators that will power the ten kicker magnet modules. One modulator part contains two pulse generators. Capacitors, inductances, and voltage dividers are in the oil tank on the left. Triggered high-pressure spark gap switches are on the platforms on the right. High voltage pulse cables to the kicker magnet emerge under the spark gaps. In the centre background are the assembled master gaps.

  1. A quantum delayed choice experiment

    CERN Document Server

    Peruzzo, Alberto; Brunner, Nicolas; Popescu, Sandu; O'Brien, Jeremy L

    2012-01-01

    Quantum systems exhibit particle-like or wave-like behaviour depending on the experimental apparatus they are confronted by. This wave-particle duality is at the heart of quantum mechanics, and is fully captured in Wheeler's famous delayed choice gedanken experiment. In this variant of the double slit experiment, the observer chooses to test either the particle or wave nature of a photon after it has passed through the slits. Here we report on a quantum delayed choice experiment, based on a quantum controlled beam-splitter, in which both particle and wave behaviours can be investigated simultaneously. The genuinely quantum nature of the photon's behaviour is tested via a Bell inequality, which here replaces the delayed choice of the observer. We observe strong Bell inequality violations, thus showing that no model in which the photon knows in advance what type of experiment it will be confronted by, hence behaving either as a particle or as wave, can account for the experimental data.

  2. Minimum Delay Moving Object Detection

    KAUST Repository

    Lao, Dong

    2017-05-14

    This thesis presents a general framework and method for detection of an object in a video based on apparent motion. The object moves, at some unknown time, differently than the “background” motion, which can be induced from camera motion. The goal of proposed method is to detect and segment the object as soon it moves in an online manner. Since motion estimation can be unreliable between frames, more than two frames are needed to reliably detect the object. Observing more frames before declaring a detection may lead to a more accurate detection and segmentation, since more motion may be observed leading to a stronger motion cue. However, this leads to greater delay. The proposed method is designed to detect the object(s) with minimum delay, i.e., frames after the object moves, constraining the false alarms, defined as declarations of detection before the object moves or incorrect or inaccurate segmentation at the detection time. Experiments on a new extensive dataset for moving object detection show that our method achieves less delay for all false alarm constraints than existing state-of-the-art.

  3. diffusive phase separation

    Directory of Open Access Journals (Sweden)

    Nobuyuki Kenmochi

    1996-01-01

    w is constrained to have double obstacles σ*≤w≤σ* (i.e., σ* and σ* are the threshold values of w. The objective of this paper is to discuss the semigroup {S(t} associated with the phase separation model, and construct its global attractor.

  4. Phase separation micro molding

    NARCIS (Netherlands)

    Vogelaar, Laura

    2005-01-01

    The research described in this thesis concerns the development of a new microfabrication method, Phase Separation Micro Molding (PSμM). While microfabrication is still best known from semiconductor industry, where it is used to integrate electrical components on a chip, the scope has immensely expan

  5. Fathering After Marital Separation

    Science.gov (United States)

    Keshet, Harry Finkelstein; Rosenthal, Kristine M.

    1978-01-01

    Deals with experiences of a group of separated or divorced fathers who chose to remain fully involved in the upbringing of their children. As they underwent transition from married parenthood to single fatherhood, these men learned that meeting demands of child care contributed to personal stability and growth. (Author)

  6. Isotope hydrograph separation

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, P. [UFZ-Umweltforschungszentrum, Centre of Environmental Research Leipzig-Halle, Leipzig (Germany)

    2000-07-01

    Storm-runoff thus reflects the complex hydraulic behaviour of drainage basins and water-links of such systems. Water of different origin may participate in the events and in this lecture, the application of isotope techniques to separate storm hydrographs into different components will be presented.

  7. Unity Through Separation

    DEFF Research Database (Denmark)

    Dabelsteen, Hans B.

    This PhD thesis asks how we can conceptualize the current separation doctrine of religion and politics in a country like Denmark, where the structure of the established church and peoplehood overlap. In order to answer this question, Hans Bruun Dabelsteen maps the current discussion of secularism...

  8. Acromioclavicular Joint Separations

    Science.gov (United States)

    2013-01-01

    Published online: 16 December 2012 # Springer Science+Business Media New York 2012 Abstract Acromioclavicular (AC) joint separations are common...injuries. The sports most likely to cause AC joint dislocations are football, soccer , hockey, rugby, and skiing, among others [9, 28, 29]. The major cause

  9. Pre-Separation Guide

    Science.gov (United States)

    1992-03-04

    SEPARATEES Defense Outplacement Referral System (DORS) Since most of us are not independently wealthy, we will need a job after separation. DORS is...Job Assistance SPOUSES OF ALL SEPARATEES As a spouse you may take advantage of preparing Standard Form 17 1’s and resu- the outplacement services

  10. Separation of Powers.

    Science.gov (United States)

    Bill of Rights in Action, 1987

    1987-01-01

    The dimensions of the separation of powers principle are explored through three lessons in the subject areas of U.S. history, U.S. government, and world history. In 1748, a French nobleman, Baron de Montesquieu, wrote a book called "The Spirit of the Laws," in which he argued that there could be no liberty when all government power was…

  11. Optimization of time-delayed feedback control of seismically excited building structures

    Institute of Scientific and Technical Information of China (English)

    Xue-ping LI; Wei-qiu ZHU; Zu-guang YING

    2008-01-01

    An optimization method for time-delayed feedback control of partially observable linear building structures subjected to seismic excitation is proposed. A time-delayed control problem of partially observable linear building structure under horizontal ground acceleration excitation is formulated and converted into that of completely observable linear structure by using separation principle. The time-delayed control forces are approximately expressed in terms of control forces without time delay. The control system is then governed by Ito stochastic differential equations for the conditional means of system states and then transformed into those for the conditional means of modal energies by using the stochastic averaging method for quasi-Hamiltonian systems. The control law is assumed to be modal velocity feedback control with time delay and the unknown control gains are determined by the modal performance indices. A three-storey building structure is taken as example to illustrate the proposal method and the numerical results are confirmed by using Monte Carlo simulation.

  12. Metal-carbon clusters: The origin of the delayed atomic ion

    Science.gov (United States)

    Davis, K. M.; Peppernick, S. J.; Castleman, A. W.

    2006-04-01

    Studies of the emission of electrons from excited metal-carbon cluster systems that include the Met-Car (M8C12, where M is Ti, Zr, and V) also have revealed the evolution of a delayed atomic ion. The source of the delayed atomic ion, which involves the emission of ionized atoms on the microsecond time scale, is the focus of this investigation. By studying the delayed ionization of mixed zirconium and titanium carbon complexes produced in a laser vaporization source coupled to a time-of-flight mass spectrometer, for the first time both the zirconium and titanium delayed atomic ions were observed to be emitted in the same experiment. These studies allowed a determination that the source of the delayed atomic ion is an excited metal dicarbide. A plausible mechanism involving the excitation of a high Rydberg state of the metal dicarbide prior to an excited ion pair separation is proposed.

  13. Correcting for Interstellar Scattering Delay in High-precision Pulsar Timing: Simulation Results

    CERN Document Server

    Palliyaguru, Nipuni; McLaughlin, Maura; Demorest, Paul; Jones, Glenn

    2015-01-01

    Light travel time changes due to gravitational waves may be detected within the next decade through precision timing of millisecond pulsars. Removal of frequency-dependent interstellar medium (ISM) delays due to dispersion and scattering is a key issue in the detection process. Current timing algorithms routinely correct pulse times of arrival (TOAs) for time-variable delays due to cold plasma dispersion. However, none of the major pulsar timing groups correct for delays due to scattering from multi-path propagation in the ISM. Scattering introduces a frequency-dependent phase change in the signal that results in pulse broadening and arrival time delays. Any method to correct the TOA for interstellar propagation effects must be based on multi-frequency measurements that can effectively separate dispersion and scattering delay terms from frequency-independent perturbations such as those due to a gravitational wave. Cyclic spectroscopy, first described in an astronomical context by Demorest (2011), is a potenti...

  14. On Hamlet's Delay in the Revenge

    Institute of Scientific and Technical Information of China (English)

    刘莎

    2009-01-01

    Hamlet is a representative tragedy written by Shakespeare. Question on Hemlet's delay has been drawing the interest of many literature critics. It is still under discussion today. This thesis focuses on analyzing the reasons for Hamlet's delay in the revenge.

  15. Individual cochlear delays measured with tone-burst-evoked otoacoustic emissions

    DEFF Research Database (Denmark)

    Pigasse, Gilles; Harte, James; Dau, Torsten

    averages. This work aims to assess the individual variability in cochlear delay. Tone-burst evoked otoacoustic emissions (TBOAEs) are used in this study to estimate cochlear delay. The OAE is analysed by separating the non-linear components of cochlear origin, and the linear reflection in the time domain....... The observed latencies as a function of frequency are qualitatively similar across subjects. For the individual subjects, the delay for each tone-burst frequency is reproducible. Defining OAE latency as the time between the onset of the stimulus and the peak of the first OAE burst yields results in agreement...

  16. Delayed-choice gedanken experiments and their realizations

    Science.gov (United States)

    Ma, Xiao-song; Kofler, Johannes; Zeilinger, Anton

    2016-01-01

    The wave-particle duality dates back to Einstein's explanation of the photoelectric effect through quanta of light and de Broglie's hypothesis of matter waves. Quantum mechanics uses an abstract description for the behavior of physical systems such as photons, electrons, or atoms. Whether quantum predictions for single systems in an interferometric experiment allow an intuitive understanding in terms of the particle or wave picture depends on the specific configuration which is being used. In principle, this leaves open the possibility that quantum systems always behave either definitely as a particle or definitely as a wave in every experimental run by a priori adapting to the specific experimental situation. This is precisely what is tried to be excluded by delayed-choice experiments, in which the observer chooses to reveal the particle or wave character of a quantum system—or even a continuous transformation between the two—at a late stage of the experiment. The history of delayed-choice gedanken experiments, which can be traced back to the early days of quantum mechanics, is reviewed. Their experimental realizations, in particular, Wheeler's delayed choice in interferometric setups as well as delayed-choice quantum erasure and entanglement swapping are discussed. The latter is particularly interesting, because it elevates the wave-particle duality of a single quantum system to an entanglement-separability duality of multiple systems.

  17. Application of ray-traced tropospheric slant delays to geodetic VLBI analysis

    Science.gov (United States)

    Hofmeister, Armin; Böhm, Johannes

    2017-02-01

    The correction of tropospheric influences via so-called path delays is critical for the analysis of observations from space geodetic techniques like the very long baseline interferometry (VLBI). In standard VLBI analysis, the a priori slant path delays are determined using the concept of zenith delays, mapping functions and gradients. The a priori use of ray-traced delays, i.e., tropospheric slant path delays determined with the technique of ray-tracing through the meteorological data of numerical weather models (NWM), serves as an alternative way of correcting the influences of the troposphere on the VLBI observations within the analysis. In the presented research, the application of ray-traced delays to the VLBI analysis of sessions in a time span of 16.5 years is investigated. Ray-traced delays have been determined with program RADIATE (see Hofmeister in Ph.D. thesis, Department of Geodesy and Geophysics, Faculty of Mathematics and Geoinformation, Technische Universität Wien. http://resolver.obvsg.at/urn:nbn:at:at-ubtuw:1-3444, 2016) utilizing meteorological data provided by NWM of the European Centre for Medium-Range Weather Forecasts (ECMWF). In comparison with a standard VLBI analysis, which includes the tropospheric gradient estimation, the application of the ray-traced delays to an analysis, which uses the same parameterization except for the a priori slant path delay handling and the used wet mapping factors for the zenith wet delay (ZWD) estimation, improves the baseline length repeatability (BLR) at 55.9% of the baselines at sub-mm level. If no tropospheric gradients are estimated within the compared analyses, 90.6% of all baselines benefit from the application of the ray-traced delays, which leads to an average improvement of the BLR of 1 mm. The effects of the ray-traced delays on the terrestrial reference frame are also investigated. A separate assessment of the RADIATE ray-traced delays is carried out by comparison to the ray-traced delays from the

  18. Application of ray-traced tropospheric slant delays to geodetic VLBI analysis

    Science.gov (United States)

    Hofmeister, Armin; Böhm, Johannes

    2017-08-01

    The correction of tropospheric influences via so-called path delays is critical for the analysis of observations from space geodetic techniques like the very long baseline interferometry (VLBI). In standard VLBI analysis, the a priori slant path delays are determined using the concept of zenith delays, mapping functions and gradients. The a priori use of ray-traced delays, i.e., tropospheric slant path delays determined with the technique of ray-tracing through the meteorological data of numerical weather models (NWM), serves as an alternative way of correcting the influences of the troposphere on the VLBI observations within the analysis. In the presented research, the application of ray-traced delays to the VLBI analysis of sessions in a time span of 16.5 years is investigated. Ray-traced delays have been determined with program RADIATE (see Hofmeister in Ph.D. thesis, Department of Geodesy and Geophysics, Faculty of Mathematics and Geoinformation, Technische Universität Wien. http://resolver.obvsg.at/urn:nbn:at:at-ubtuw:1-3444, 2016) utilizing meteorological data provided by NWM of the European Centre for Medium-Range Weather Forecasts (ECMWF). In comparison with a standard VLBI analysis, which includes the tropospheric gradient estimation, the application of the ray-traced delays to an analysis, which uses the same parameterization except for the a priori slant path delay handling and the used wet mapping factors for the zenith wet delay (ZWD) estimation, improves the baseline length repeatability (BLR) at 55.9% of the baselines at sub-mm level. If no tropospheric gradients are estimated within the compared analyses, 90.6% of all baselines benefit from the application of the ray-traced delays, which leads to an average improvement of the BLR of 1 mm. The effects of the ray-traced delays on the terrestrial reference frame are also investigated. A separate assessment of the RADIATE ray-traced delays is carried out by comparison to the ray-traced delays from the

  19. Microgravity Passive Phase Separator

    Science.gov (United States)

    Paragano, Matthew; Indoe, William; Darmetko, Jeffrey

    2012-01-01

    A new invention disclosure discusses a structure and process for separating gas from liquids in microgravity. The Microgravity Passive Phase Separator consists of two concentric, pleated, woven stainless- steel screens (25-micrometer nominal pore) with an axial inlet, and an annular outlet between both screens (see figure). Water enters at one end of the center screen at high velocity, eventually passing through the inner screen and out through the annular exit. As gas is introduced into the flow stream, the drag force exerted on the bubble pushes it downstream until flow stagnation or until it reaches an equilibrium point between the surface tension holding bubble to the screen and the drag force. Gas bubbles of a given size will form a front that is moved further down the length of the inner screen with increasing velocity. As more bubbles are added, the front location will remain fixed, but additional bubbles will move to the end of the unit, eventually coming to rest in the large cavity between the unit housing and the outer screen (storage area). Owing to the small size of the pores and the hydrophilic nature of the screen material, gas does not pass through the screen and is retained within the unit for emptying during ground processing. If debris is picked up on the screen, the area closest to the inlet will become clogged, so high-velocity flow will persist farther down the length of the center screen, pushing the bubble front further from the inlet of the inner screen. It is desired to keep the velocity high enough so that, for any bubble size, an area of clean screen exists between the bubbles and the debris. The primary benefits of this innovation are the lack of any need for additional power, strip gas, or location for venting the separated gas. As the unit contains no membrane, the transport fluid will not be lost due to evaporation in the process of gas separation. Separation is performed with relatively low pressure drop based on the large surface

  20. Dynamic Cournot Duopoly Game with Delay

    Directory of Open Access Journals (Sweden)

    A. A. Elsadany

    2014-01-01

    Full Text Available The delay Cournot duopoly game is studied. Dynamical behaviors of the game are studied. Equilibrium points and their stability are studied. The results show that the delayed system has the same Nash equilibrium point and the delay can increase the local stability region.

  1. Modelling delay propagation within an airport network

    NARCIS (Netherlands)

    Pyrgiotis, N.; Malone, K.M.; Odoni, A.

    2013-01-01

    We describe an analytical queuing and network decomposition model developed to study the complex phenomenon of the propagation of delays within a large network of major airports. The Approximate Network Delays (AND) model computes the delays due to local congestion at individual airports and capture

  2. Modelling delay propagation within an airport network

    NARCIS (Netherlands)

    Pyrgiotis, N.; Malone, K.M.; Odoni, A.

    2013-01-01

    We describe an analytical queuing and network decomposition model developed to study the complex phenomenon of the propagation of delays within a large network of major airports. The Approximate Network Delays (AND) model computes the delays due to local congestion at individual airports and

  3. Stability criteria for T-S fuzzy systems with interval time-varying delays and nonlinear perturbations based on geometric progression delay partitioning method.

    Science.gov (United States)

    Chen, Hao; Zhong, Shouming; Li, Min; Liu, Xingwen; Adu-Gyamfi, Fehrs

    2016-07-01

    In this paper, a novel delay partitioning method is proposed by introducing the theory of geometric progression for the stability analysis of T-S fuzzy systems with interval time-varying delays and nonlinear perturbations. Based on the common ratio α, the delay interval is unequally separated into multiple subintervals. A newly modified Lyapunov-Krasovskii functional (LKF) is established which includes triple-integral terms and augmented factors with respect to the length of every related proportional subintervals. In addition, a recently developed free-matrix-based integral inequality is employed to avoid the overabundance of the enlargement when dealing with the derivative of the LKF. This innovative development can dramatically enhance the efficiency of obtaining the maximum upper bound of the time delay. Finally, much less conservative stability criteria are presented. Numerical examples are conducted to demonstrate the significant improvements of this proposed approach.

  4. GPS Separator HD

    CERN Multimedia

    2016-01-01

    Footage of the 70 degree ISOLDE GPS separator magnet MAG70 as well as the switchyard for the Central Mass and GLM (GPS Low Mass) and GHM (GPS High Mass) beamlines in the GPS separator zone. In the GPS20 vacuum sector equipment such as the long GPS scanner 482 / 483 unit, faraday cup FC 490, vacuum valves and wiregrid piston WG210 and WG475 and radiation monitors can also be seen. Also the RILIS laser guidance and trajectory can be seen, the GPS main beamgate switch box and the actual GLM, GHM and Central Beamline beamgates in the beamlines as well as the first electrostatic quadrupoles for the GPS lines. Close up of the GHM deflector plates motor and connections and the inspection glass at the GHM side of the switchyard.

  5. HRS Separator HD

    CERN Multimedia

    2016-01-01

    Footage of the 90 and 60 degree ISOLDE HRS separator magnets in the HRS separator zone. In the two vacuum sectors HRS20 and HRS30 equipment such as the HRS slits SL240, the HRS faraday cup FC300 and wiregrid WG210 can be spotted. Vacuum valves, turbo pumps, beamlines, quadrupoles, water and compressed air connections, DC and signal cabling can be seen throughout the video. The HRS main and user beamgate in the beamline between MAG90 and MAG60 and its switchboxes as well as all vacuum bellows and flanges are shown. Instrumentation such as the HRS scanner unit 482 / 483, the HRS WG470 wiregrid and slits piston can be seen. The different quadrupoles and supports are shown as well as the RILIS guidance tubes and installation at the magnets and the different radiation monitors.

  6. Nylon separators. [thermal degradation

    Science.gov (United States)

    Lim, H. S.

    1977-01-01

    A nylon separator was placed in a flooded condition in K0H solution and heated at various high temperatures ranging from 60 C to 110 C. The weight decrease was measured and the molecular weight and decomposition product were analyzed to determine: (1) the effect of K0H concentration on the hydrolysis rate; (2) the effect of K0H concentration on nylon degradation; (3) the activation energy at different K0H concentrations; and (4) the effect of oxygen on nylon degradation. The nylon hydrolysis rate is shown to increase as K0H concentration is decreased 34%, giving a maximum rate at about 16%. Separator hydrolysis is confirmed by molecular weight decrease in age of the batteries, and the reaction of nylon with molecular oxygen is probably negligible, compared to hydrolysis. The extrapolated rate value from the high temperature experiment correlates well with experimental values at 35 degrees.

  7. Battery separator manufacturing process

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, N.I.; Sugarman, N.

    1974-12-27

    A battery with a positive plate, a negative plate, and a separator of polymeric resin having a degree of undesirable hydrophobia, solid below 180/sup 0/F, extrudable as a hot melt, and resistant to degradation by at least either acids or alkalies positioned between the plates is described. The separator comprises a nonwoven mat of fibers, the fibers being comprised of the polymeric resin and a wetting agent in an amount of 0.5 to 20 percent by weight based on the weight of the resin with the amount being incompatible with the resin below the melting point of the resin such that the wetting agent will bloom over a period of time at ambient temperatures in a battery, yet being compatible with the resin at the extrusion temperature and bringing about blooming to the surface of the fibers when the fibers are subjected to heat and pressure.

  8. Unity Through Separation

    DEFF Research Database (Denmark)

    Dabelsteen, Hans B.

    analysis, Dabelsteen study Danish secularism as an ideological concept. He finds that the conceptual structure of Danish secularism holds separation-as-principled distance at its core. Institutionally this particularly pertains to the establishment arrangement, and in practice it translates...... and proposes two conceptual expansions. The first is to include modest establishment in a framework of secularism defensible by political liberalism, and the second is to consider secularism in close connection to a theory of peoplehood. Methodologically positioned between interpretive realism and policy...... into the principle of treating everybody equally (with religious freedom, equality and Danish peoplehood as the most important principles adjacent to secularism). In a study of the historical roots of the separation doctrine and two current policy cases (same-sex marriage and reforms of church governance...

  9. Acoustophoresis separation method

    Science.gov (United States)

    Heyman, Joseph S. (Inventor)

    1993-01-01

    A method and apparatus are provided for acoustophoresis, i.e., the separation of species via acoustic waves. An ultrasonic transducer applies an acoustic wave to one end of a sample container containing at least two species having different acoustic absorptions. The wave has a frequency tuned to or harmonized with the point of resonance of the species to be separated. This wave causes the species to be driven to an opposite end of the sample container for removal. A second ultrasonic transducer may be provided to apply a second, oppositely directed acoustic wave to prevent undesired streaming. In addition, a radio frequency tuned to the mechanical resonance and coupled with a magnetic field can serve to identify a species in a medium comprising species with similar absorption coefficients, whereby an acoustic wave having a frequency corresponding to this gyrational rate can then be applied to sweep the identified species to one end of the container for removal.

  10. Separation of enantiomers

    CERN Document Server

    Todd , Matthew H

    2014-01-01

    In one handy volume this handbook summarizes the most common synthetic methods for the separation of racemic mixtures, allowing an easy comparison of the different strategies described in the literature.Alongside classical methods, the authors also consider kinetic resolutions, dynamic kinetic resolutions, divergent reactions of a racemic mixture, and a number of ""neglected"" cases not covered elsewhere, such as the use of circularly polarized light, polymerizations, ""ripening"" processes, dynamic combinatorial chemistry, and several thermodynamic processes. The result is a thorough introdu

  11. Separation Logic and Concurrency

    Science.gov (United States)

    Bornat, Richard

    Concurrent separation logic is a development of Hoare logic adapted to deal with pointers and concurrency. Since its inception, it has been enhanced with a treatment of permissions to enable sharing of data between threads, and a treatment of variables as resource alongside heap cells as resource. An introduction to the logic is given with several examples of proofs, culminating in a treatment of Simpson's 4-slot algorithm, an instance of racy non-blocking concurrency.

  12. BOLD delay times using group delay in sickle cell disease

    Science.gov (United States)

    Coloigner, Julie; Vu, Chau; Bush, Adam; Borzage, Matt; Rajagopalan, Vidya; Lepore, Natasha; Wood, John

    2016-03-01

    Sickle cell disease (SCD) is an inherited blood disorder that effects red blood cells, which can lead to vasoocclusion, ischemia and infarct. This disease often results in neurological damage and strokes, leading to morbidity and mortality. Functional Magnetic Resonance Imaging (fMRI) is a non-invasive technique for measuring and mapping the brain activity. Blood Oxygenation Level-Dependent (BOLD) signals contain also information about the neurovascular coupling, vascular reactivity, oxygenation and blood propagation. Temporal relationship between BOLD fluctuations in different parts of the brain provides also a mean to investigate the blood delay information. We used the induced desaturation as a label to profile transit times through different brain areas, reflecting oxygen utilization of tissue. In this study, we aimed to compare blood flow propagation delay times between these patients and healthy subjects in areas vascularized by anterior, middle and posterior cerebral arteries. In a group comparison analysis with control subjects, BOLD changes in these areas were found to be almost simultaneous and shorter in the SCD patients, because of their increased brain blood flow. Secondly, the analysis of a patient with a stenosis on the anterior cerebral artery indicated that signal of the area vascularized by this artery lagged the MCA signal. These findings suggest that sickle cell disease causes blood propagation modifications, and that these changes could be used as a biomarker of vascular damage.

  13. Innovative Separations Technologies

    Energy Technology Data Exchange (ETDEWEB)

    J. Tripp; N. Soelberg; R. Wigeland

    2011-05-01

    Reprocessing used nuclear fuel (UNF) is a multi-faceted problem involving chemistry, material properties, and engineering. Technology options are available to meet a variety of processing goals. A decision about which reprocessing method is best depends significantly on the process attributes considered to be a priority. New methods of reprocessing that could provide advantages over the aqueous Plutonium Uranium Reduction Extraction (PUREX) and Uranium Extraction + (UREX+) processes, electrochemical, and other approaches are under investigation in the Fuel Cycle Research and Development (FCR&D) Separations Campaign. In an attempt to develop a revolutionary approach to UNF recycle that may have more favorable characteristics than existing technologies, five innovative separations projects have been initiated. These include: (1) Nitrogen Trifluoride for UNF Processing; (2) Reactive Fluoride Gas (SF6) for UNF Processing; (3) Dry Head-end Nitration Processing; (4) Chlorination Processing of UNF; and (5) Enhanced Oxidation/Chlorination Processing of UNF. This report provides a description of the proposed processes, explores how they fit into the Modified Open Cycle (MOC) and Full Recycle (FR) fuel cycles, and identifies performance differences when compared to 'reference' advanced aqueous and fluoride volatility separations cases. To be able to highlight the key changes to the reference case, general background on advanced aqueous solvent extraction, advanced oxidative processes (e.g., volumetric oxidation, or 'voloxidation,' which is high temperature reaction of oxide UNF with oxygen, or modified using other oxidizing and reducing gases), and fluorination and chlorination processes is provided.

  14. Colour Separation and Aversion

    Directory of Open Access Journals (Sweden)

    Sarah M Haigh

    2012-05-01

    Full Text Available Aversion to achromatic patterns is well documented but relatively little is known about discomfort from chromatic patterns. Large colour differences are uncommon in the natural environment and deviation from natural statistics makes images uncomfortable (Fernandez and Wilkins 2008, Perception, 37(7, 1098–113; Juricevic et al 2010, Perception, 39(7, 884–899. We report twelve studies documenting a linear increase in aversion to chromatic square-wave gratings as a function of the separation in UCS chromaticity between the component bars, independent of their luminance contrast. Two possible explanations for the aversion were investigated: (1 accommodative response, or (2 cortical metabolic demand. We found no correlation between chromaticity separation and accommodative lag or variance in lag, measured using an open-field autorefractor. However, near infrared spectroscopy of the occipital cortex revealed a larger oxyhaemoglobin response to patterns with large chromaticity separation. The aversion may be cortical in origin and does not appear to be due to accommodation.

  15. The neutron long counter NERO for studies of β-delayed neutron emission in the r-process

    Science.gov (United States)

    Pereira, J.; Hosmer, P.; Lorusso, G.; Santi, P.; Couture, A.; Daly, J.; Del Santo, M.; Elliot, T.; Görres, J.; Herlitzius, C.; Kratz, K.-L.; Lamm, L. O.; Lee, H. Y.; Montes, F.; Ouellette, M.; Pellegrini, E.; Reeder, P.; Schatz, H.; Schertz, F.; Schnorrenberger, L.; Smith, K.; Stech, E.; Strandberg, E.; Ugalde, C.; Wiescher, M.; Wöhr, A.

    2010-06-01

    The neutron long counter NERO was built at the National Superconducting Cyclotron Laboratory (NSCL), Michigan State University, for measuring β-delayed neutron-emission probabilities. The detector was designed to work in conjunction with a β-delay implantation station, so that β decays and β-delayed neutrons emitted from implanted nuclei can be measured simultaneously. The high efficiency of about 40%, for the range of energies of interest, along with the small background, are crucial for measuring β-delayed neutron emission branchings for neutron-rich r-process nuclei produced as low intensity fragmentation beams in in-flight separator facilities.

  16. Determination for β-delayed fission probability of 230Ac

    Institute of Scientific and Technical Information of China (English)

    袁双贵; 杨维凡; 徐岩冰; 肖永厚; 罗亦孝

    2002-01-01

    The 230Ra has been produced via 232Th-2p reaction induced by 60 MeV/u 18O ion irradia-tion of natural thorium. The radium was radiochemically separated from the mixture of thorium andreaction products. Thin Ra sources in which 230Ac was got through 230Ra β- → 230Ac were pre-pared for observing fission fragments from β-delayed fission of 230Ac. The sources were exposedto the mica fission track detectors and measured by the HPGe γ detector. The precursor 230Ac wasidentified by means of observed two fission events as well as γ spectra, and the β-delayed fissionprobability of 230Ac was obtained to be (1.19±0.85) × 10-8.

  17. Analysis of deterministic cyclic gene regulatory network models with delays

    CERN Document Server

    Ahsen, Mehmet Eren; Niculescu, Silviu-Iulian

    2015-01-01

    This brief examines a deterministic, ODE-based model for gene regulatory networks (GRN) that incorporates nonlinearities and time-delayed feedback. An introductory chapter provides some insights into molecular biology and GRNs. The mathematical tools necessary for studying the GRN model are then reviewed, in particular Hill functions and Schwarzian derivatives. One chapter is devoted to the analysis of GRNs under negative feedback with time delays and a special case of a homogenous GRN is considered. Asymptotic stability analysis of GRNs under positive feedback is then considered in a separate chapter, in which conditions leading to bi-stability are derived. Graduate and advanced undergraduate students and researchers in control engineering, applied mathematics, systems biology and synthetic biology will find this brief to be a clear and concise introduction to the modeling and analysis of GRNs.

  18. A precursor of β-delayed fission:230Ac

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The 230Ra has been produced via multinucleon transfer and dissipativefragmentation of heavy target in the 60 MeV/u 18O ion reaction with natural thorium.The radium was radiochemically separated from irradiated thorium targets. 230Acwas obtained by 230Ra β-→ 230Ac. Thin Ra sources were prepared for observing fissionfragments from β-delayed fission of 230Ac. The sources were exposed to the micafission track detectors and measured by a HPGe γ detector. The two fission eventswere obtained and could been assigned to theβ-delayed fission of 230Ac. The β-delayedfission probability of 230Ac was determined to be (1.19+0.85) × 10-8.

  19. Fluxbranes Delaying Brane-Antibrane Annihilation

    CERN Document Server

    Kim, H

    2003-01-01

    By intersecting the RR charged D_p - bar{D}_p pair (p=6, 4, 2, 0) with the RR F7-brane and by intersecting the NSNS charged F1-bar{F1} and NS5-bar{NS5} pairs with the NSNS F6-branes, the possibility of stabilizing the brane-antibrane systems is considered. The behavior of the corresponding supergravity solutions indicates that the RR F7-brane content of the solution plays the role of keeping the brane and the antibrane from annihilating each other completely since the two-brane configuration structure still persists in the vanishing inter-brane distance limit of the supergravity solution. In terms of the stringy description, we interpret this as representing that the RR F7-brane ``delays'' the brane-antibrane annihilation process but only until this non-supersymmetric and hence unstable F7-brane itself decays. Then next, the behavior of the supergravity solutions representing F1-bar{F1} and NS5-bar{NS5} again for vanishing inter-brane separation reveals that as they approach, these ``NS''-charged brane and an...

  20. Delayed models for simplified musical instruments.

    Science.gov (United States)

    Barjau, Ana; Gibiat, Vincent

    2003-07-01

    Most musical instruments contain, at their very basis, a continuous vibrating element (string or air column) which can be treated as a one-dimensional system. Its oscillation is obtained either through an initial condition or by means of a continuous energy input through a nonlinear device. In both cases and as a first approach, the excitation can be localized at one single point, and the continuous system can be considered as a linear one. The coupling between these two elements is often represented through a convolution integral. This convolution will be rewritten here in a way that different phenomena taking place in the continuous element (internal losses, radiation at the ends...) are separated. Different choices in the formulation of these processes and some mathematical manipulation will lead to either algebraic iterative or delayed differential equations. These equations are valid for any form of energy input. Once this energy input is defined, they can be used to simulate the behavior of different instruments in a more efficient way than that of traditional convolution. Moreover, these equations allow an analytical analysis of possible regimes using the tools of nonlinear dynamical systems (NLDS). The case of woodwinds will be emphasized throughout the paper, while that of strings will be presented briefly for the sake of completeness.

  1. Reactor shutdown delays medical procedures

    Science.gov (United States)

    Gwynne, Peter

    2008-01-01

    A longer-than-expected maintenance shutdown of the Canadian nuclear reactor that produces North America's entire supply of molybdenum-99 - from which the radioactive isotopes technetium-99 and iodine-131 are made - caused delays to the diagnosis and treatment of thousands of seriously ill patients last month. Technetium-99 is a key component of nuclear-medicine scans, while iodine-131 is used to treat cancer and other diseases of the thyroid. Production eventually resumed, but only after the Canadian government had overruled the Canadian Nuclear Safety Commission (CNSC), which was still concerned about the reactor's safety.

  2. Delay modeling in logic simulation

    Energy Technology Data Exchange (ETDEWEB)

    Acken, J. M.; Goldstein, L. H.

    1980-01-01

    As digital integrated circuit size and complexity increases, the need for accurate and efficient computer simulation increases. Logic simulators such as SALOGS (SAndia LOGic Simulator), which utilize transition states in addition to the normal stable states, provide more accurate analysis than is possible with traditional logic simulators. Furthermore, the computational complexity of this analysis is far lower than that of circuit simulation such as SPICE. An eight-value logic simulation environment allows the use of accurate delay models that incorporate both element response and transition times. Thus, timing simulation with an accuracy approaching that of circuit simulation can be accomplished with an efficiency comparable to that of logic simulation. 4 figures.

  3. Delay Variation Model with Two Service Queues

    Directory of Open Access Journals (Sweden)

    Filip Rezac

    2010-01-01

    Full Text Available Delay in VoIP technology is very unpleasant issue and therefore a voice packets prioritization must be ensured. To maintain the high call quality a maximum information delivery time from the sender to the recipient is set to 150 ms. This paper focuses on the design of a mathematical model of end-to-end delay of a VoIP connection, in particular on a delay variation. It describes all partial delay components and mechanisms, their generation, facilities and mathematical formulations. A new approach to the delay variation model is presented and its validation has been done by experimention.

  4. H∞ State Feedback Delay-dependent Control for Discrete Systems with Multi-time-delay

    Institute of Scientific and Technical Information of China (English)

    Bai-Da Qu

    2005-01-01

    In this paper,H∞ state feedback control with delay information for discrete systems with multi-time-delay is discussed. Making use of linear matrix inequality (LMI) approach, a time-delay-dependent criterion for a discrete system with multi-time-delay to satisfy H∞ performance indices is induced, and then a strategy for H∞ state feedback control with delay values for plant with multi-time-delay is obtained. By solving corresponding LMI, a delay-dependent state feedback controller satisfying H∞ performance indices is designed. Finally, a simulation example demonstrates the validity of the proposed approach.

  5. Asymptotic Delay Analysis for Cross-Layer Delay-Based Routing in Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Philippe Jacquet

    2007-01-01

    Full Text Available This paper addresses the problem of the evaluation of the delay distribution via analytical means in IEEE 802.11 wireless ad hoc networks. We show that the asymptotic delay distribution can be expressed as a power law. Based on the latter result, we present a cross-layer delay estimation protocol and we derive new delay-distribution-based routing algorithms, which are well adapted to the QoS requirements of real-time multimedia applications. In fact, multimedia services are not sensitive to average delays, but rather to the asymptotic delay distributions. Indeed, video streaming applications drop frames when they are received beyond a delay threshold, determined by the buffer size. Although delay-distribution-based routing is an NP-hard problem, we show that it can be solved in polynomial time when the delay threshold is large, because of the asymptotic power law distribution of the link delays.

  6. Delay-Dependent Observers for Uncertain Nonlinear Time-Delay Systems

    Directory of Open Access Journals (Sweden)

    Dongmei Yan

    2013-05-01

    Full Text Available This paper is concerned with the observer design problem for a class of discrete-time uncertain nonlinear systems with time-varying delay. The nonlinearities are assumed to satisfy global Lipschitz conditions which appear in both the state and measurement equations. The uncertainties are assumed to be time-varying but norm-bounded. Two Luenberger-like observers are proposed. One is delay observer and the other is delay-free observer. The delay observer which has an internal time delay is applicable when the time delay is known. The delay-free observer which does not use delayed information is especially applicable when the time delay is not known explicitly. Delay-dependent conditions for the existences of these two observers are derived based on Lyapunpv functional approach. Based on these conditions, the observer gains are obtained using the cone complementarity linearization algorithm. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.

  7. Precise delay measurement through combinatorial logic

    Science.gov (United States)

    Burke, Gary R. (Inventor); Chen, Yuan (Inventor); Sheldon, Douglas J. (Inventor)

    2010-01-01

    A high resolution circuit and method for facilitating precise measurement of on-chip delays for FPGAs for reliability studies. The circuit embeds a pulse generator on an FPGA chip having one or more groups of LUTS (the "LUT delay chain"), also on-chip. The circuit also embeds a pulse width measurement circuit on-chip, and measures the duration of the generated pulse through the delay chain. The pulse width of the output pulse represents the delay through the delay chain without any I/O delay. The pulse width measurement circuit uses an additional asynchronous clock autonomous from the main clock and the FPGA propagation delay can be displayed on a hex display continuously for testing purposes.

  8. Estimation of time delay by coherence analysis

    CERN Document Server

    Govindan, R B; Kopper, F; Claussen, J C; Deuschl, G

    2004-01-01

    Using coherence analysis (which is an extensively used method to study the correlations in frequency domain, between two simultaneously measured signals) we estimate the time delay between two signals. This method is suitable for time delay estimation of narrow band coherence signals for which the conventional methods cannot be reliably applied. We show by analysing coupled R\\"ossler attractors with a known delay, that the method yields satisfactory results. Then, we apply this method to human pathologic tremor. The delay between simultaneously measured traces of Electroencephalogram (EEG) and Electromyogram (EMG) data of subjects with essential hand tremor is calculated. We find that there is a delay of 11-27 milli-seconds ($ms$) between the tremor correlated parts (cortex) of the brain (EEG) and the trembling hand (EMG) which is in agreement with the experimentally observed delay value of 15 $ms$ for the cortico-muscular conduction time. By surrogate analysis we calculate error-bars of the estimated delay.

  9. Synchronization of time-delay chaotic systems on small-world networks with delayed coupling

    Institute of Scientific and Technical Information of China (English)

    Qi Wei; Wang Ying-Hai

    2009-01-01

    By using the well-known Ikeda model as the node dynamics,this paper studies synchronization of time-delay systems on small-world networks where the connections between units involve time delays.It shows that,in contrast with the undelayed case,networks with delays can actually synchronize more easily.Specifically,for randomly distributed delays,time-delayed mutual coupling suppresses the chaotic behaviour by stabilizing a fixed point that is unstable for the uncoupled dynamical system.

  10. Time-delay feedback control in a delayed dynamical chaos system and its applications

    Institute of Scientific and Technical Information of China (English)

    Ye Zhi-Yong; Yang Guang; Deng Cun-Bing

    2011-01-01

    The feedback control of a delayed dynamical system, which also includes various chaotic systems with time delays, is investigated. On the basis of stability analysis of a nonautonomons system with delays, some simple yet less conservative criteria are obtained for feedback control in a delayed dynamical system. Finally, the theoretical result is applied to a typical class of chaotic Lorenz system and Chua circuit with delays. Numerical simulations are also given to verify the theoretical results.

  11. [Delayed post effort muscle soreness].

    Science.gov (United States)

    Coudreuse, J M; Dupont, P; Nicol, C

    2004-08-01

    Muscle intolerance to exercise may result from different processes. Diagnosis involves confirming first the source of pain, then potential pathological myalgia. Delayed-onset muscle soreness (DOMS), commonly referred as tiredness, occurs frequently in sport. DOMS usually develops 12-48 h after intensive and/or unusual eccentric muscle action. Symptoms usually involve the quadriceps muscle group but may also affect the hamstring and triceps surae groups. The muscles are sensitive to palpation, contraction and passive stretch. Acidosis, muscle spasm and microlesions in both connective and muscle tissues may explain the symptoms. However, inflammation appears to be the most common explanation. Interestingly, there is strong evidence that the progression of the exercise-induced muscle injury proceeds no further in the absence of inflammation. Even though unpleasant, DOMS should not be considered as an indicator of muscle damage but, rather, a sign of the regenerative process, which is well known to contribute to the increased muscle mass. DOMS can be associated with decreased proprioception and range of motion, as well as maximal force and activation. DOMS disappears 2-10 days before complete functional recovery. This painless period is ripe for additional joint injuries. Similarly, if some treatments are well known to attenuate DOMS, none has been demonstrated to accelerate either structural or functional recovery. In terms of the role of the inflammatory process, these treatments might even delay overall recovery.

  12. Elite athletes and pubertal delay.

    Science.gov (United States)

    Kapczuk, Karina

    2017-10-01

    Intensive physical training and participation in competitive sports during childhood and early adolescence may affect athletes' pubertal development. On the other hand, pubertal timing, early or late, may impact on an athlete selection for a particular sport. Genetic predisposition, training load, nutritional status and psychological stress determine athletes' pubertal timing. Athletes that practice esthetic sports, especially gymnasts, are predisposed to a delay in pubertal development. The growing evidence indicates that energy deficiency, not a systemic training per se, plays a crucial role in the pathogenesis of functional hypothalamic hypogonadism in female athletes. Metabolic and psychologic stress activate hypothalamic-pituitary-adrenal axis and suppress hypothalamic-pituitary-ovarian axis. Female athletes who do not begin secondary sexual development by the age of 14 or menstruation by the age of 16 warrant a comprehensive evaluation and a targeted treatment. Somatic growth and sexual maturation of elite female athletes are largely sport-specific since each sport favors a particular somatotype and requires a specific training. Chronic negative energy balance resulting from a systemic physical training and inadequate energy intake may delay pubertal development in elite athletes. Youth athletes, especially those engaged in competitive sports that emphasize prepubertal or lean appearance, are at risk of developing relative energy deficiency in sport associated with disordered eating or eating disorders. Management strategies should address the complex conditions underlying functional hypothalamic hypogonadism.

  13. Eddy current separation apparatus, separation module, separation method and method for adjusting an eddy current separation apparatus

    NARCIS (Netherlands)

    Rem, P.C.; Bakker, M.C.M.; Berkhout, S.P.M.; Rahman, M.A.

    2012-01-01

    Eddy current separation apparatus (1) for separating particles (20) from a particle stream (w), wherein the apparatus (1) comprises a separator drum (4) adapted to create a first particle fraction (21) and a second particle fraction (23), a feeding device (2) upstream of the separator drum (4) for s

  14. Column-coupling strategies for multidimensional electrophoretic separation techniques.

    Science.gov (United States)

    Kler, Pablo A; Sydes, Daniel; Huhn, Carolin

    2015-01-01

    Multidimensional electrophoretic separations represent one of the most common strategies for dealing with the analysis of complex samples. In recent years we have been witnessing the explosive growth of separation techniques for the analysis of complex samples in applications ranging from life sciences to industry. In this sense, electrophoretic separations offer several strategic advantages such as excellent separation efficiency, different methods with a broad range of separation mechanisms, and low liquid consumption generating less waste effluents and lower costs per analysis, among others. Despite their impressive separation efficiency, multidimensional electrophoretic separations present some drawbacks that have delayed their extensive use: the volumes of the columns, and consequently of the injected sample, are significantly smaller compared to other analytical techniques, thus the coupling interfaces between two separations components must be very efficient in terms of providing geometrical precision with low dead volume. Likewise, very sensitive detection systems are required. Additionally, in electrophoretic separation techniques, the surface properties of the columns play a fundamental role for electroosmosis as well as the unwanted adsorption of proteins or other complex biomolecules. In this sense the requirements for an efficient coupling for electrophoretic separation techniques involve several aspects related to microfluidics and physicochemical interactions of the electrolyte solutions and the solid capillary walls. It is interesting to see how these multidimensional electrophoretic separation techniques have been used jointly with different detection techniques, for intermediate detection as well as for final identification and quantification, particularly important in the case of mass spectrometry. In this work we present a critical review about the different strategies for coupling two or more electrophoretic separation techniques and the

  15. SEPARATION OF PLUTONIUM

    Science.gov (United States)

    Maddock, A.G.; Smith, F.

    1959-08-25

    A method is described for separating plutonium from uranium and fission products by treating a nitrate solution of fission products, uranium, and hexavalent plutonium with a relatively water-insoluble fluoride to adsorb fission products on the fluoride, treating the residual solution with a reducing agent for plutonium to reduce its valence to four and less, treating the reduced plutonium solution with a relatively insoluble fluoride to adsorb the plutonium on the fluoride, removing the solution, and subsequently treating the fluoride with its adsorbed plutonium with a concentrated aqueous solution of at least one of a group consisting of aluminum nitrate, ferric nitrate, and manganous nitrate to remove the plutonium from the fluoride.

  16. POLONIUM SEPARATION PROCESS

    Science.gov (United States)

    Karraker, D.G.

    1959-07-14

    A liquid-liquid extraction process is presented for the recovery of polonium from lead and bismuth. According to the invention an acidic aqueous chloride phase containing the polonium, lead, and bismuth values is contacted with a tributyl phosphate ether phase. The polonium preferentially enters the organic phase which is then separated and washed with an aqueous hydrochloric solution to remove any lead or bismuth which may also have been extracted. The now highly purified polonium in the organic phase may be transferred to an aqueous solution by extraction with aqueous nitric acid.

  17. PLUTONIUM SEPARATION METHOD

    Science.gov (United States)

    Beaufait, L.J. Jr.; Stevenson, F.R.; Rollefson, G.K.

    1958-11-18

    The recovery of plutonium ions from neutron irradiated uranium can be accomplished by bufferlng an aqueous solutlon of the irradiated materials containing tetravalent plutonium to a pH of 4 to 7, adding sufficient acetate to the solution to complex the uranyl present, adding ferric nitrate to form a colloid of ferric hydroxide, plutonlum, and associated fission products, removing and dissolving the colloid in aqueous nitric acid, oxldizlng the plutonium to the hexavalent state by adding permanganate or dichromate, treating the resultant solution with ferric nitrate to form a colloid of ferric hydroxide and associated fission products, and separating the colloid from the plutonlum left in solution.

  18. Experimental realization of Wheeler's delayed-choice gedanken experiment.

    Science.gov (United States)

    Jacques, Vincent; Wu, E; Grosshans, Frédéric; Treussart, François; Grangier, Philippe; Aspect, Alain; Roch, Jean-François

    2007-02-16

    Wave-particle duality is strikingly illustrated by Wheeler's delayed-choice gedanken experiment, where the configuration of a two-path interferometer is chosen after a single-photon pulse has entered it: Either the interferometer is closed (that is, the two paths are recombined) and the interference is observed, or the interferometer remains open and the path followed by the photon is measured. We report an almost ideal realization of that gedanken experiment with single photons allowing unambiguous which-way measurements. The choice between open and closed configurations, made by a quantum random number generator, is relativistically separated from the entry of the photon into the interferometer.

  19. Fullerene photoemission time delay explores molecular cavity in attoseconds

    CERN Document Server

    Magrakvelidze, Maia; Dixit, Gopal; Madjet, Mohamed El-Amine; Chakraborty, Himadri S

    2014-01-01

    Time-resolved photoelectron spectroscopy can probe interference oscillations in C60 valence emissions that produce series of minima whose energy separation depends on the molecular size. We show that the quantum phase associated with these minima exhibits rapid variations due to electron correlations, causing rich structures in the photoemission time delay. These findings provide a way to utilize temporal information to access the fullerene cavity size, that is making the time to "see" the space, and can be generalized to photoemissions from clusters and nanostructures.

  20. Printed Spacecraft Separation System

    Energy Technology Data Exchange (ETDEWEB)

    Holmans, Walter [Planetary Systems Corporation, Silver Springs, MD (United States); Dehoff, Ryan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-10-01

    In this project Planetary Systems Corporation proposed utilizing additive manufacturing (3D printing) to manufacture a titanium spacecraft separation system for commercial and US government customers to realize a 90% reduction in the cost and energy. These savings were demonstrated via “printing-in” many of the parts and sub-assemblies into one part, thus greatly reducing the labor associated with design, procurement, assembly and calibration of mechanisms. Planetary Systems Corporation redesigned several of the components of the separation system based on additive manufacturing principles including geometric flexibility and the ability to fabricate complex designs, ability to combine multiple parts of an assembly into a single component, and the ability to optimize design for specific mechanical property targets. Shock absorption was specifically targeted and requirements were established to attenuate damage to the Lightband system from shock of initiation. Planetary Systems Corporation redesigned components based on these requirements and sent the designs to Oak Ridge National Laboratory to be printed. ORNL printed the parts using the Arcam electron beam melting technology based on the desire for the parts to be fabricated from Ti-6Al-4V based on the weight and mechanical performance of the material. A second set of components was fabricated from stainless steel material on the Renishaw laser powder bed technology due to the improved geometric accuracy, surface finish, and wear resistance of the material. Planetary Systems Corporation evaluated these components and determined that 3D printing is potentially a viable method for achieving significant cost and savings metrics.

  1. Virus separation using membranes.

    Science.gov (United States)

    Grein, Tanja A; Michalsky, Ronald; Czermak, Peter

    2014-01-01

    Industrial manufacturing of cell culture-derived viruses or virus-like particles for gene therapy or vaccine production are complex multistep processes. In addition to the bioreactor, such processes require a multitude of downstream unit operations for product separation, concentration, or purification. Similarly, before a biopharmaceutical product can enter the market, removal or inactivation of potential viral contamination has to be demonstrated. Given the complexity of biological solutions and the high standards on composition and purity of biopharmaceuticals, downstream processing is the bottleneck in many biotechnological production trains. Membrane-based filtration can be an economically attractive and efficient technology for virus separation. Viral clearance, for instance, of up to seven orders of magnitude has been reported for state of the art polymeric membranes under best conditions.This chapter summarizes the fundamentals of virus ultrafiltration, diafiltration, or purification with adsorptive membranes. In lieu of an impractical universally applicable protocol for virus filtration, application of these principles is demonstrated with two examples. The chapter provides detailed methods for production, concentration, purification, and removal of a rod-shaped baculovirus (Autographa californica M nucleopolyhedrovirus, about 40 × 300 nm in size, a potential vector for gene therapy, and an industrially important protein expression system) or a spherical parvovirus (minute virus of mice, 22-26 nm in size, a model virus for virus clearance validation studies).

  2. Delayed birth of distillable entanglement in the evolution of bound entangled states

    CERN Document Server

    Derkacz, Łukasz

    2010-01-01

    The dynamical creation of entanglement between three-level atoms coupled to the common vacuum is investigated. For the class of bound entangled initial states we show that the dynamics of closely separated atoms generates stationary distillable entanglement of asymptotic states. We also find that the effect of delayed sudden birth of distillable entanglement occurs in the case of atoms separated by a distance comparable with the radiation wavelength.

  3. Conversion of linear time-invariant time-delay feedback systems into delay-differential equations with commensurate delays

    Science.gov (United States)

    Yamazaki, Tatsuya; Hagiwara, Tomomichi

    2014-08-01

    A new stability analysis method of time-delay systems (TDSs) called the monodromy operator approach has been studied under the assumption that a TDS is represented as a time-delay feedback system consisting of a finite-dimensional linear time-invariant (LTI) system and a pure delay. For applying this approach to TDSs described by delay-differential equations (DDEs), the problem of converting DDEs into representation as time-delay feedback systems has been studied. With regard to such a problem, it was shown that, under discontinuous initial functions, it is natural to define the solutions of DDEs in two different ways, and the above conversion problem was solved for each of these two definitions. More precisely, the solution of a DDE was represented as either the state of the finite-dimensional part of a time-delay feedback system or a part of the output of another time-delay feedback system, depending on which definition of the DDE solution one is talking about. Motivated by the importance in establishing a thorough relationship between time-delay feedback systems and DDEs, this paper discusses the opposite problem of converting time-delay feedback systems into representation as DDEs, including the discussions about the conversion of the initial conditions. We show that the state of (the finite-dimensional part of) a time-delay feedback system can be represented as the solution of a DDE in the sense of one of the two definitions, while its 'essential' output can be represented as that of another DDE in the sense of the other type of definition. Rigorously speaking, however, it is also shown that the latter representation is possible regardless of the initial conditions, while some initial condition could prevent the conversion into the former representation. This study hence establishes that the representation of TDSs as time-delay feedback systems possesses higher ability than that with DDEs, as description methods for LTI TDSs with commensurate delays.

  4. Mixed delay-independent/delay-dependent stability of uncertain linear time-delayed systems

    Institute of Scientific and Technical Information of China (English)

    LI Wenlin; DONG Rui

    2004-01-01

    @@ Consider uncertain linear time delay systems described by the following state equation: x(t)=[A0+Δ A0(t)]x(t)+∑ri=1[Ai+ΔAi(t)]x(t-τi).(1) x(t)=(t)t∈[-,0];=maxri=1{τi}(2) where Δ A0(*) and Δ Ai(*)(i=1,…,r) are real matrix functions.Δ Ai(t)=LiFi(t)Ei,ΔA0(t)=L0F0(t)E0, where Li,Ei are known real constant matrices and Fi(t) are unknown real time-varying matrices with Lebesgue measurable elements satisfying ‖Fi(t)‖I,t(i=0,1,…,r). In this note, we develop the methods of robust stability which is dependent on the size of some delays but independent on the size of the others and is based on the solution of linear matrix inequalities.

  5. Plasma separation: physical separation at the molecular level

    Science.gov (United States)

    Gueroult, Renaud; Rax, Jean-Marcel; Fisch, Nathaniel J.

    2016-09-01

    Separation techniques are usually divided in two categories depending on the nature of the discriminating property: chemical or physical. Further to this difference, physical and chemical techniques differ in that chemical separation typically occurs at the molecular level, while physical separation techniques commonly operate at the macroscopic scale. Separation based on physical properties can in principle be realized at the molecular or even atomic scale by ionizing the mixture. This is in essence plasma based separation. Due to this fundamental difference, plasma based separation stands out from other separation techniques, and features unique properties. In particular, plasma separation allows separating different elements or chemical compounds based on physical properties. This could prove extremely valuable to separate macroscopically homogeneous mixtures made of substances of similar chemical formulation. Yet, the realization of plasma separation techniques' full potential requires identifying and controlling basic mechanisms in complex plasmas which exhibit suitable separation properties. In this paper, we uncover the potential of plasma separation for various applications, and identify the key physics mechanisms upon which hinges the development of these techniques.

  6. Virtual unit delay for digital frequency adaptive T/4 delay phase-locked loop system

    DEFF Research Database (Denmark)

    Yang, Yongheng; Zhou, Keliang; Blaabjerg, Frede

    2016-01-01

    -controller/processor with a fixed sampling rate considering the cost and complexity, where the number of unit delays that have been adopted should be an integer. For instance, in conventional digital control systems, a single-phase T/4 Delay Phase-Locked Loop (PLL) system takes 50 unit delays (i.e., in a 50-Hz system...... Delay PLL system should be done in its implementation. This process will result in performance degradation in the digital control system, as the exactly required number of delays is not realized. Hence, in this paper, a Virtual Unit Delay (VUD) has been proposed to address such challenges to the digital...... T/4 Delay PLL system. The proposed VUD adopts linear interpolation polynomial to approximate the fractional delay induced by the varying grid frequency in such a way that the control performance is enhanced. The proposed VUD has been demonstrated on a digitally controlled T/4 Delay PLL system...

  7. Variable-delay feedback control of unstable steady states in retarded time-delayed systems

    CERN Document Server

    Gjurchinovski, Aleksandar; 10.1103/PhysRevE.81.016209

    2010-01-01

    We study the stability of unstable steady states in scalar retarded time-delayed systems subjected to a variable-delay feedback control. The important aspect of such a control problem is that time-delayed systems are already infinite-dimensional before the delayed feedback control is turned on. When the frequency of the modulation is large compared to the system's dynamics, the analytic approach consists of relating the stability properties of the resulting variable-delay system with those of an analogous distributed delay system. Otherwise, the stability domains are obtained by a numerical integration of the linearized variable-delay system. The analysis shows that the control domains are significantly larger than those in the usual time-delayed feedback control, and that the complexity of the domain structure depends on the form and the frequency of the delay modulation.

  8. Post-CTS Delay Insertion

    Directory of Open Access Journals (Sweden)

    Jianchao Lu

    2010-01-01

    clock skew operation is performed only at the clock sinks in order to preserve the structure and the optimizations implemented in the clock tree synthesis stage. The methodology is implemented as a linear programming model amenable to two design objectives: fixing timing violations or optimizing the clock period. Experimental results show that the clock networks of the largest ISCAS'89 circuits can be corrected post-CTS to resolve the timing conflicts in approximately 90% of the circuits with minimal delay insertion (0.159  ×  clock period per clock path on average. It is also shown that the majority of the clock period improvement achievable through unrestricted clock skew scheduling are obtained through very limited insertion (≈43% average improvement through 10% of max insertion.

  9. Transition delay using control theory.

    Science.gov (United States)

    Bagheri, S; Henningson, D S

    2011-04-13

    This review gives an account of recent research efforts to use feedback control for the delay of laminar-turbulent transition in wall-bounded shear flows. The emphasis is on reducing the growth of small-amplitude disturbances in the boundary layer using numerical simulations and a linear control approach. Starting with the application of classical control theory to two-dimensional perturbations developing in spatially invariant flows, flow control based on control theory has progressed towards more realistic three-dimensional, spatially inhomogeneous flow configurations with localized sensing/actuation. The development of low-dimensional models of the Navier-Stokes equations has played a key role in this progress. Moreover, shortcomings and future challenges, as well as recent experimental advances in this multi-disciplinary field, are discussed.

  10. Exact dynamics of stochastic linear delayed systems: Application to spatiotemporal coordination of comoving agents

    Science.gov (United States)

    McKetterick, Thomas John; Giuggioli, Luca

    2014-10-01

    Delayed dynamics result from finite transmission speeds of a signal in the form of energy, mass, or information. In stochastic systems the resulting lagged dynamics challenge our understanding due to the rich behavioral repertoire encompassing monotonic, oscillatory, and unstable evolution. Despite the vast literature, quantifying this rich behavior is limited by a lack of explicit analytic studies of high-dimensional stochastic delay systems. Here we fill this gap for systems governed by a linear Langevin equation of any number of delays and spatial dimensions with additive Gaussian noise. By exploiting Laplace transforms we are able to derive an exact time-dependent analytic solution of the Langevin equation. By using characteristic functionals we are able to construct the full time dependence of the multivariate probability distribution of the stochastic process as a function of the delayed and nondelayed random variables. As an application we consider interactions in animal collective movement that go beyond the traditional assumption of instantaneous alignment. We propose models for coordinated maneuvers of comoving agents applicable to recent empirical findings in pigeons and bats whereby individuals copy the heading of their neighbors with some delay. We highlight possible strategies that individual pairs may adopt to reduce the variance in their velocity difference and/or in their spatial separation. We also show that a minimum in the variance of the spatial separation at long times can be achieved with certain ratios of measurement to reaction delay.

  11. Fuzzy delay model based fault simulator for crosstalk delay fault test generation in asynchronous sequential circuits

    Indian Academy of Sciences (India)

    S Jayanthy; M C Bhuvaneswari

    2015-02-01

    In this paper, a fuzzy delay model based crosstalk delay fault simulator is proposed. As design trends move towards nanometer technologies, more number of new parameters affects the delay of the component. Fuzzy delay models are ideal for modelling the uncertainty found in the design and manufacturing steps. The fault simulator based on fuzzy delay detects unstable states, oscillations and non-confluence of settling states in asynchronous sequential circuits. The fuzzy delay model based fault simulator is used to validate the test patterns produced by Elitist Non-dominated sorting Genetic Algorithm (ENGA) based test generator, for detecting crosstalk delay faults in asynchronous sequential circuits. The multi-objective genetic algorithm, ENGA targets two objectives of maximizing fault coverage and minimizing number of transitions. Experimental results are tabulated for SIS benchmark circuits for three gate delay models, namely unit delay model, rise/fall delay model and fuzzy delay model. Experimental results indicate that test validation using fuzzy delay model is more accurate than unit delay model and rise/fall delay model.

  12. Particle separator scroll vanes

    Energy Technology Data Exchange (ETDEWEB)

    Lastrina, F. A.; Mayer, J. C.; Pommer, L. M.

    1985-07-09

    An inlet particle separator for a gas turbine engine is provided with unique vanes distributed around an entrance to a particle collection chamber. The vanes are uniquely constructed to direct extraneous particles that enter the engine into the collection chamber and prevent the particles from rebounding back into the engine's air flow stream. The vanes are provided with several features to accomplish this function, including upstream faces that are sharply angled towards air flow stream direction to cause particles to bounce towards the collection chamber. In addition, throat regions between the vanes cause a localized air flow acceleration and a focusing of the particles that aid in directing the particles in a proper direction.

  13. Nebulized therapy. SEPAR year.

    Science.gov (United States)

    Olveira, Casilda; Muñoz, Ana; Domenech, Adolfo

    2014-12-01

    Inhaled drugs are deposited directly in the respiratory tract. They therefore achieve higher concentrations with faster onset of action and fewer side effects than when used systemically. Nebulized drugs are mainly recommended for patients that require high doses of bronchodilators, when they need to inhale drugs that only exist in this form (antibiotics or dornase alfa) or when they are unable to use other inhalation devices. Technological development in recent years has led to new devices that optimize pulmonary deposits and reduce the time needed for treatment. In this review we focus solely on drugs currently used, or under investigation, for nebulization in adult patients; basically bronchodilators, inhaled steroids, antibiotics, antifungals, mucolytics and others such as anticoagulants, prostanoids and lidocaine. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

  14. Block copolymer battery separator

    Energy Technology Data Exchange (ETDEWEB)

    Wong, David; Balsara, Nitash Pervez

    2016-04-26

    The invention herein described is the use of a block copolymer/homopolymer blend for creating nanoporous materials for transport applications. Specifically, this is demonstrated by using the block copolymer poly(styrene-block-ethylene-block-styrene) (SES) and blending it with homopolymer polystyrene (PS). After blending the polymers, a film is cast, and the film is submerged in tetrahydrofuran, which removes the PS. This creates a nanoporous polymer film, whereby the holes are lined with PS. Control of morphology of the system is achieved by manipulating the amount of PS added and the relative size of the PS added. The porous nature of these films was demonstrated by measuring the ionic conductivity in a traditional battery electrolyte, 1M LiPF.sub.6 in EC/DEC (1:1 v/v) using AC impedance spectroscopy and comparing these results to commercially available battery separators.

  15. Block copolymer battery separator

    Science.gov (United States)

    Wong, David; Balsara, Nitash Pervez

    2016-04-26

    The invention herein described is the use of a block copolymer/homopolymer blend for creating nanoporous materials for transport applications. Specifically, this is demonstrated by using the block copolymer poly(styrene-block-ethylene-block-styrene) (SES) and blending it with homopolymer polystyrene (PS). After blending the polymers, a film is cast, and the film is submerged in tetrahydrofuran, which removes the PS. This creates a nanoporous polymer film, whereby the holes are lined with PS. Control of morphology of the system is achieved by manipulating the amount of PS added and the relative size of the PS added. The porous nature of these films was demonstrated by measuring the ionic conductivity in a traditional battery electrolyte, 1M LiPF.sub.6 in EC/DEC (1:1 v/v) using AC impedance spectroscopy and comparing these results to commercially available battery separators.

  16. Dynamics of Nonlinear Time-Delay Systems

    CERN Document Server

    Lakshmanan, Muthusamy

    2010-01-01

    Synchronization of chaotic systems, a patently nonlinear phenomenon, has emerged as a highly active interdisciplinary research topic at the interface of physics, biology, applied mathematics and engineering sciences. In this connection, time-delay systems described by delay differential equations have developed as particularly suitable tools for modeling specific dynamical systems. Indeed, time-delay is ubiquitous in many physical systems, for example due to finite switching speeds of amplifiers in electronic circuits, finite lengths of vehicles in traffic flows, finite signal propagation times in biological networks and circuits, and quite generally whenever memory effects are relevant. This monograph presents the basics of chaotic time-delay systems and their synchronization with an emphasis on the effects of time-delay feedback which give rise to new collective dynamics. Special attention is devoted to scalar chaotic/hyperchaotic time-delay systems, and some higher order models, occurring in different bran...

  17. Modeling delayed processes in biological systems

    Science.gov (United States)

    Feng, Jingchen; Sevier, Stuart A.; Huang, Bin; Jia, Dongya; Levine, Herbert

    2016-09-01

    Delayed processes are ubiquitous in biological systems and are often characterized by delay differential equations (DDEs) and their extension to include stochastic effects. DDEs do not explicitly incorporate intermediate states associated with a delayed process but instead use an estimated average delay time. In an effort to examine the validity of this approach, we study systems with significant delays by explicitly incorporating intermediate steps. We show that such explicit models often yield significantly different equilibrium distributions and transition times as compared to DDEs with deterministic delay values. Additionally, different explicit models with qualitatively different dynamics can give rise to the same DDEs revealing important ambiguities. We also show that DDE-based predictions of oscillatory behavior may fail for the corresponding explicit model.

  18. Memorized discrete systems and time-delay

    CERN Document Server

    Luo, Albert C J

    2017-01-01

    This book examines discrete dynamical systems with memory—nonlinear systems that exist extensively in biological organisms and financial and economic organizations, and time-delay systems that can be discretized into the memorized, discrete dynamical systems. It book further discusses stability and bifurcations of time-delay dynamical systems that can be investigated through memorized dynamical systems as well as bifurcations of memorized nonlinear dynamical systems, discretization methods of time-delay systems, and periodic motions to chaos in nonlinear time-delay systems. The book helps readers find analytical solutions of MDS, change traditional perturbation analysis in time-delay systems, detect motion complexity and singularity in MDS; and determine stability, bifurcation, and chaos in any time-delay system.

  19. Delays in the management of retroperitoneal sarcomas

    DEFF Research Database (Denmark)

    Seinen, Jojanneke; Almquist, Martin; Styring, Emelie

    2010-01-01

    at the general practitioner, 36 days at local hospitals, and 55 days at the sarcoma centre. Conclusion. Centralization per se is not sufficient for optimized and efficient management. Our findings suggest that delays can be minimized by direct referral of patients from primary health care to sarcoma centers...... sarcoma in the southern Sweden health care region 2003-2009 were eligible for the study. Data on referrals and diagnostic investigations were collected from clinical files from primary health care, local hospitals, and from the sarcoma centre. Lead times were divided into patient delays and health care...... delays caused by primary health care, local hospitals, or procedures at the sarcoma centre. Results. Complete data were available from 33 patients and demonstrated a median patient delay of 23 days (0-17 months) and median health care delay of 94 days (1-40 months) with delays of median 15 days...

  20. Delays in the management of retroperitoneal sarcomas

    DEFF Research Database (Denmark)

    Seinen, Jojanneke; Almquist, Martin; Styring, Emelie

    2010-01-01

    at the general practitioner, 36¿days at local hospitals, and 55¿days at the sarcoma centre. Conclusion. Centralization per se is not sufficient for optimized and efficient management. Our findings suggest that delays can be minimized by direct referral of patients from primary health care to sarcoma centers...... sarcoma in the southern Sweden health care region 2003-2009 were eligible for the study. Data on referrals and diagnostic investigations were collected from clinical files from primary health care, local hospitals, and from the sarcoma centre. Lead times were divided into patient delays and health care...... delays caused by primary health care, local hospitals, or procedures at the sarcoma centre. Results. Complete data were available from 33 patients and demonstrated a median patient delay of 23¿days (0-17¿months) and median health care delay of 94¿days (1-40¿months) with delays of median 15¿days...

  1. Delay banking for air traffic management

    Science.gov (United States)

    Green, Steven M. (Inventor)

    2007-01-01

    A method and associated system for time delay banking for aircraft arrival time, aircraft departure time and/or en route flight position. The delay credit value for a given flight may decrease with passage of time and may be transferred to or traded with other flights having the same or a different user (airline owner or operator). The delay credit value for a given aircraft flight depends upon an initial delay credit value, which is determined by a central system and depends upon one or more other flight characteristics. Optionally, the delay credit value decreases with passage of time. Optionally, a transaction cost is assessed against a delay credit value that is used on behalf of another flight with the same user or is traded with a different user.

  2. Time Delay Estimation Algoritms for Echo Cancellation

    Directory of Open Access Journals (Sweden)

    Kirill Sakhnov

    2011-01-01

    Full Text Available The following case study describes how to eliminate echo in a VoIP network using delay estimation algorithms. It is known that echo with long transmission delays becomes more noticeable to users. Thus, time delay estimation, as a part of echo cancellation, is an important topic during transmission of voice signals over packetswitching telecommunication systems. An echo delay problem associated with IP-based transport networks is discussed in the following text. The paper introduces the comparative study of time delay estimation algorithm, used for estimation of the true time delay between two speech signals. Experimental results of MATLab simulations that describe the performance of several methods based on cross-correlation, normalized crosscorrelation and generalized cross-correlation are also presented in the paper.

  3. Phase changes in delay propagation networks

    CERN Document Server

    Belkoura, Seddik

    2016-01-01

    The analysis of the dynamics of delays propagation is one of the major topics inside Air Transport Management research. Delays are generated by the elements of the system, but their propagation is a global process fostered by relationships inside the network. If the topology of such propagation process has been extensively studied in the literature, little attention has been devoted to the fact that such topology may have a dynamical nature. Here we differentiate between two phases of the system by applying two causality metrics, respectively describing the standard phase (i.e. propagation of normal delays) and a disrupted one (corresponding to abnormal and unexpected delays). We identify the critical point triggering the change of the topology of the system, in terms of delays magnitude, using a historical data set of flights crossing Europe in 2011. We anticipate that the proposed results will open new doors towards the understanding of the delay propagation dynamics and the mitigation of extreme events.

  4. Photonic Nonlinear Transient Computing with Multiple-Delay Wavelength Dynamics

    Science.gov (United States)

    Martinenghi, Romain; Rybalko, Sergei; Jacquot, Maxime; Chembo, Yanne K.; Larger, Laurent

    2012-06-01

    We report on the experimental demonstration of a hybrid optoelectronic neuromorphic computer based on a complex nonlinear wavelength dynamics including multiple delayed feedbacks with randomly defined weights. This neuromorphic approach is based on a new paradigm of a brain-inspired computational unit, intrinsically differing from Turing machines. This recent paradigm consists in expanding the input information to be processed into a higher dimensional phase space, through the nonlinear transient response of a complex dynamics excited by the input information. The computed output is then extracted via a linear separation of the transient trajectory in the complex phase space. The hyperplane separation is derived from a learning phase consisting of the resolution of a regression problem. The processing capability originates from the nonlinear transient, resulting in nonlinear transient computing. The computational performance is successfully evaluated on a standard benchmark test, namely, a spoken digit recognition task.

  5. Gravity separation for oil wastewater treatment

    OpenAIRE

    Golomeova, Mirjana; Zendelska, Afrodita; Krstev, Boris; Krstev, Aleksandar

    2010-01-01

    In this paper, the applications of gravity separation for oil wastewater treatment are presented. Described is operation on conventional gravity separation and parallel plate separation. Key words: gravity separation, oil, conventional gravity separation, parallel plate separation.

  6. Gravity separation for oil wastewater treatment

    OpenAIRE

    Golomeova, Mirjana; Zendelska, Afrodita; Krstev, Boris; Krstev, Aleksandar

    2010-01-01

    In this paper, the applications of gravity separation for oil wastewater treatment are presented. Described is operation on conventional gravity separation and parallel plate separation. Key words: gravity separation, oil, conventional gravity separation, parallel plate separation.

  7. Prehospital delay in acute coronary syndrome--an analysis of the components of delay

    DEFF Research Database (Denmark)

    Ottesen, Michael Mundt; Dixen, Ulrik; Torp-Pedersen, Christian;

    2004-01-01

    more frequently atypical symptoms and increased prehospital delay caused by prolonged physician and transportation delay. Physician delay among women and men were 69 and 16 min, respectively. Patients with prior myocardial infarction had reduced prehospital delay, which was caused by shorter decision...... admitted with acute coronary syndrome is warranted. METHODS: A structured interview was conducted on 250 consecutive patients admitted alive with acute coronary syndrome. RESULTS: Median prehospital, decision, physician and transportation delays were 107, 74, 25 and 22 min, respectively. Women (n=77) had...... of acute coronary syndrome among women, and thereby contributes to unnecessary long delay to treatment. The patient's prior experience and interpretation has a significant influence on behaviour....

  8. Time-delay and fractional derivatives

    OpenAIRE

    Tenreiro Machado JA

    2011-01-01

    This paper proposes the calculation of fractional algorithms based on time-delay systems. The study starts by analyzing the memory properties of fractional operators and their relation with time delay. Based on the Fourier analysis an approximation of fractional derivatives through time-delayed samples is developed. Furthermore, the parameters of the proposed approximation are estimated by means of genetic algorithms. The results demonstrate the feasibility of the new perspective.

  9. Treatment of bronchial ruptures by delayed surgery

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Objective:To study the causes that resulted in delayed surgery for bronchial ruptures and the results.Methods:The cases with the bronchial ruptures by the delayed surgery last decade were retrospectively reviewed.The causes and unsatisfactory results were analysed.Results:The severe complications usually occurred after the delayed surgery and the results were not as satisfactory as those by early surgery.Conclusion:The bronchial ruptures ought to be operated in the early stage after being wounded.

  10. Examining Relationships between Executive Functioning and Delay Aversion in Attention Deficit Hyperactivity Disorder

    Science.gov (United States)

    Karalunas, Sarah L.; Huang-Pollock, Cynthia L.

    2011-01-01

    Although motivation and cognition are often examined separately, recent theory suggests that a delay-averse motivational style may negatively impact development of executive functions (EFs), such as working memory (WM) and response inhibition (RI) for children with Attention Deficit Hyperactivity Disorder (ADHD; Sonuga-Barke, 2002). This model…

  11. Developmental Delay in Moderately Preterm-Born Children with Low Socioeconomic Status : Risks Multiply

    NARCIS (Netherlands)

    Potijk, Marieke R; Kerstjens, Jorien M; Bos, Arend F; Reijneveld, Sijmen A; de Winter, Andrea F

    2013-01-01

    Objective To assess separate and joint effects of low socioeconomic status (SES) and moderate prematurity on preschool developmental delay. Study design Prospective cohort study with a community-based sample of preterm-and term-born children (Longitudinal Preterm Outcome Project). We assessed SES on

  12. The influence of the group delay of digital filters on acoustic decay measurements

    DEFF Research Database (Denmark)

    Sobreira-Seoane, Manuel A.; Cabo, David Pérez; Jacobsen, Finn

    2012-01-01

    to their phase response. In this investigation the two components are separated and the phase error analyzed in terms of the group delay of the filters. Linear phase FIR filters and minimum phase IIR filters fulfilling the class 1 requirements of the IEC 61260 standard have been designed, and their errors...

  13. Developmental Delay in Moderately Preterm-Born Children with Low Socioeconomic Status : Risks Multiply

    NARCIS (Netherlands)

    Potijk, Marieke R; Kerstjens, Jorien M; Bos, Arend F; Reijneveld, Sijmen A; de Winter, Andrea F

    2013-01-01

    Objective To assess separate and joint effects of low socioeconomic status (SES) and moderate prematurity on preschool developmental delay. Study design Prospective cohort study with a community-based sample of preterm-and term-born children (Longitudinal Preterm Outcome Project). We assessed SES on

  14. Daytime Sleep Patterns in Preschool Children with Autism, Developmental Delay, and Typical Development

    Science.gov (United States)

    Schwichtenberg, A. J.; Iosif, Ana-Maria; Goodlin-Jones, Beth; Tang, Karen; Anders, Thomas

    2011-01-01

    The present study examined daytime sleep patterns in 3 groups of preschool-aged children: children with autism, children with developmental delay, and children who were developing typically. Sleep was assessed in 194 children via actigraphy and parent-report sleep diaries for 7 consecutive days on 3 separate occasions over 6 months. Children with…

  15. Existence and Stability for Stochastic Partial Differential Equations with Infinite Delay

    Directory of Open Access Journals (Sweden)

    Jing Cui

    2014-01-01

    Full Text Available We consider a class of neutral stochastic partial differential equations with infinite delay in real separable Hilbert spaces. We derive the existence and uniqueness of mild solutions under some local Carathéodory-type conditions and also exponential stability in mean square of mild solutions as well as its sample paths. Some known results are generalized and improved.

  16. Vortical structures responsible for delayed stall in an idealized humpback whale flipper model

    Science.gov (United States)

    Kim, Heesu; Kim, Jooha; Choi, Haecheon

    2016-11-01

    In this study, we investigate how the tubercles on the leading edge of an idealized humpback whale flipper model delay the stall. Oil-surface visualization is performed to see the surface flow pattern on the suction surface, and PIV is conducted in several streamwise and crossflow planes at different attack angles (α). Without tubercles, leading edge separation first occurs near the tip region and progresses inboard with increasing α. With tubercles, however, two types of vortical motions are observed at the mid-span. The first is streamwise vortex arrays which are dominant at α 9° , and these structures appear near the trailing edge. These two types of vortical motions delay flow separation at the peak regions of the mid-span, eliminating the spanwise stall progression and resulting in delayed stall. At α = 16° at which the tubercle model stalls, a large-scale streamwise vortex is originated from flow separation near the root region. This structure delays flow separation at the mid-span, leading to higher lift coefficient. Supported by NRF-2014M3C1B1033848.

  17. Temperature Dependent Wire Delay Estimation in Floorplanning

    DEFF Research Database (Denmark)

    Winther, Andreas Thor; Liu, Wei; Nannarelli, Alberto;

    2011-01-01

    Due to large variations in temperature in VLSI circuits and the linear relationship between metal resistance and temperature, the delay through wires of the same length can be different. Traditional thermal aware floorplanning algorithms use wirelength to estimate delay and routability. In this w......Due to large variations in temperature in VLSI circuits and the linear relationship between metal resistance and temperature, the delay through wires of the same length can be different. Traditional thermal aware floorplanning algorithms use wirelength to estimate delay and routability...

  18. Angle-resolved time delay in photoemission

    CERN Document Server

    Wätzel, Jonas; Pavlyukh, Yaroslav; Berakdar, Jamal

    2014-01-01

    We investigate theoretically the relative time delay of photoelectrons originating from different atomic subshells of noble gases. This quantity was measured via attosecond streaking and studied theoretically by Schultze et al. [Science 328, 1658 (2010)] for neon. A substantial discrepancy was found between the measured and the calculated values of the relative time delay. Several theoretical studies were put forward to resolve this issue, e.g., by including correlation effects. In the present paper we explore a further aspect, namely the directional dependence of time delay. In contrast to neon, for argon target a strong angular dependence of time delay is found near a Cooper minimum.

  19. Dimensional reduction of nonlinear time delay systems

    Directory of Open Access Journals (Sweden)

    M. S. Fofana

    2005-01-01

    infinite-dimensional problem without the assumption of small time delay. This dimensional reduction is illustrated in this paper with the delay versions of the Duffing and van der Pol equations. For both nonlinear delay equations, transcendental characteristic equations of linearized stability are examined through Hopf bifurcation. The infinite-dimensional nonlinear solutions of the delay equations are decomposed into stable and centre subspaces, whose respective dimensions are determined by the linearized stability of the transcendental equations. Linear semigroups, infinitesimal generators, and their adjoint forms with bilinear pairings are the additional candidates for the infinite-dimensional reduction.

  20. Group Delay of High Q Antennas

    DEFF Research Database (Denmark)

    Bahramzy, Pevand; Pedersen, Gert Frølund

    2013-01-01

    become an issue, when working with high Q antennas, because of the steep phase shift over the frequency. In this paper, it is measured how large group delay variations can become, when going from a low Q antenna to a high Q antenna. The group delay of a low Q antenna is shown to be around 1.3 ns, whereas...... a high Q antenna has group delay of around 22 ns. It is due to this huge group delay variation characteristics of high Q antennas, that signal distortion might occur in the radio system with high Q antennas....

  1. Reducing Transmitted Vibration Using Delayed Hysteretic Suspension

    Directory of Open Access Journals (Sweden)

    Lahcen Mokni

    2011-01-01

    Full Text Available Previous numerical and experimental works show that time delay technique is efficient to reduce transmissibility of vibration in a single pneumatic chamber by controlling the pressure in the chamber. The present work develops an analytical study to demonstrate the effectiveness of such a technique in reducing transmitted vibrations. A quarter-car model is considered and delayed hysteretic suspension is introduced in the system. Analytical predictions based on perturbation analysis show that a delayed hysteretic suspension enhances vibration isolation comparing to the case where the nonlinear damping is delay-independent.

  2. Delay Computation Using Fuzzy Logic Approach

    Directory of Open Access Journals (Sweden)

    Ramasesh G. R.

    2012-10-01

    Full Text Available The paper presents practical application of fuzzy sets and system theory in predicting delay, with reasonable accuracy, a wide range of factors pertaining to construction projects. In this paper we shall use fuzzy logic to predict delays on account of Delayed supplies and Labor shortage. It is observed that the project scheduling software use either deterministic method or probabilistic method for computation of schedule durations, delays, lags and other parameters. In other words, these methods use only quantitative inputs leaving-out the qualitative aspects associated with individual activity of work. The qualitative aspect viz., the expertise of the mason or the lack of experience can have a significant impact on the assessed duration. Such qualitative aspects do not find adequate representation in the Project Scheduling software. A realistic project is considered for which a PERT chart has been prepared using showing all the major activities in reasonable detail. This project has been periodically updated until its completion. It is observed that some of the activities are delayed due to extraneous factors resulting in the overall delay of the project. The software has the capability to calculate the overall delay through CPM (Critical Path Method when each of the activity-delays is reported. We shall now demonstrate that by using fuzzy logic, these delays could have been predicted well in advance.

  3. Efficacy of Herbicides When Spray Solution Application Is Delayed

    Directory of Open Access Journals (Sweden)

    Peter M. Eure

    2013-01-01

    Full Text Available Information is limited concerning the impact of delaying applications of pesticides after solution preparation on efficacy. Experiments were conducted to determine weed control when diclosulam, dimethenamid-P, flumioxazin, fomesafen, imazethapyr, pendimethalin, and S-metolachlor were applied preemergence the day of solution preparation or 3, 6, and 9 days after solution preparation. Herbicide solutions were applied on the same day regardless of when prepared. Control of broadleaf signalgrass, common lambsquarters, entireleaf morningglory, and Palmer amaranth by these herbicides was not reduced regardless of when herbicide solutions were prepared. Surprisingly entireleaf morningglory control by all herbicides increased when herbicide application was delayed by 9 days. In separate experiments, control of broadleaf signalgrass by clethodim, common ragweed by glyphosate and lactofen, entireleaf morningglory by lactofen, Italian rye grass by glyphosate and paraquat, and Palmer amaranth by atrazine, dicamba, glufosinate, glyphosate, imazethapyr, lactofen, and 2,4-D was affected more by increase in weed size due to delayed application than the time between solution preparation and application.

  4. Separation by column chromatography of cells active in delayed-onset hypersensitivities.

    Science.gov (United States)

    Godfrey, H P; Gell, P G

    1976-01-01

    Lymph node cells from guinea-pigs contact sensitive to 1-thiocyamo-2,4-dinitrobenzene have been fractionated by affinity chromatography over modified polyacrylamide beads. Cells mediating lymphokine release in response to active sensitizer were depleted only by chromatography over dinitrophyenyl (DNP) containing substrates and could be specifically eluted with DNP-glycine. DNP rosette-forming cells (RFC) were equally well depleted by chromatography using either DNP or trinitrophenyl containing materials but could not be eluted from the columns by DNP-glycine. While the antigen receptors of cells mediating the release of macrophage agglutination factor in response to DNP-containing antigens and of DNP-RFC were found to be hapten-specific, their specificity was shown to differ using chromatography over trinitrophenyl containing polyacrylamide. PMID:776818

  5. Delay-range-dependent chaos synchronization approach under varying time-lags and delayed nonlinear coupling.

    Science.gov (United States)

    Zaheer, Muhammad Hamad; Rehan, Muhammad; Mustafa, Ghulam; Ashraf, Muhammad

    2014-11-01

    This paper proposes a novel state feedback delay-range-dependent control approach for chaos synchronization in coupled nonlinear time-delay systems. The coupling between two systems is esteemed to be nonlinear subject to time-lags. Time-varying nature of both the intrinsic and the coupling delays is incorporated to broad scope of the present study for a better-quality synchronization controller synthesis. Lyapunov-Krasovskii (LK) functional is employed to derive delay-range-dependent conditions that can be solved by means of the conventional linear matrix inequality (LMI)-tools. The resultant control approach for chaos synchronization of the master-slave time-delay systems considers non-zero lower bound of the intrinsic as well as the coupling time-delays. Further, the delay-dependent synchronization condition has been established as a special case of the proposed LK functional treatment. Furthermore, a delay-range-dependent condition, independent of the delay-rate, has been provided to address the situation when upper bound of the delay-derivative is unknown. A robust state feedback control methodology is formulated for synchronization of the time-delay chaotic networks against the L2 norm bounded perturbations by minimizing the L2 gain from the disturbance to the synchronization error. Numerical simulation results are provided for the time-delay chaotic networks to show effectiveness of the proposed delay-range-dependent chaos synchronization methodologies. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  6. Selectivity in capillary electrokinetic separations

    NARCIS (Netherlands)

    de Zeeuw, R.A; de Jong, G.J.; Ensing, K

    1999-01-01

    This review gives a survey of selectivity modes in capillary electrophoresis separations in pharmaceutical analysis and bioanalysis. Despite the high efficiencies of these separation techniques, good selectivity is required to allow quantitation or identification of a Chemistry and Toxicology, parti

  7. Physical Separation in the Workplace

    DEFF Research Database (Denmark)

    Stea, Diego; Foss, Nicolai Juul; Holdt Christensen, Peter

    2015-01-01

    Physical separation is pervasive in organizations, and has powerful effects on employee motivation and organizational behaviors. However, research shows that workplace separation is characterized by a variety of tradeoffs, tensions, and challenges that lead to both positive and negative outcomes...

  8. A consensus dynamics with delay-induced instability can self-regulate for stability via agent regrouping.

    Science.gov (United States)

    Hyong Koh, M; Sipahi, Rifat

    2016-11-01

    Dynamics of many multi-agent systems is influenced by communication/activation delays τ. In the presence of delays, there exists a certain margin called the delay margin τ(*), less than which system stability holds. This margin depends strongly on agents' dynamics and the agent network. In this article, three key elements, namely, the delay margin, network graph, and a distance threshold conditioning two agents' connectivity are considered in a multi-agent consensus dynamics under delay τ. We report that when the dynamics is unstable under this delay, its states can be naturally bounded, even for arbitrarily large threshold values, preventing agents to disperse indefinitely. This mechanism can also make the system recover stability in a self-regulating manner, mainly induced by network separation and enhanced delay margin. Under certain conditions, unstable consensus dynamics can keep separating into smaller stable subnetwork dynamics until all agents stabilize in their respective subnetworks. Results are then demonstrated on a previously validated robot coordination model, where specifically robustness of τ(*) is studied against the delay τinh inherently present in the orientation measurements of the robots. To this end, a mathematical framework to compute τ(*) with respect to τinh in quasi-state is developed, demonstrating that τ(*) can be sensitive to τinh, yet robot regrouping and stabilization of subnetworks is still possible.

  9. New models and distributions of the electrical breakdown time delay in neon

    Energy Technology Data Exchange (ETDEWEB)

    Stamenkovic, S N, E-mail: ssuzana@pmf.ni.ac.rs [Department of Physics, University of Nis, P.O. BOX 224, 18001 Nis (Serbia)

    2010-11-01

    The measurements of the electrical breakdown time delay t{sub d} for a wide range of working voltages and at different preionization levels are presented. The statistical breakdown time delay t{sub s} and the discharge formative time t{sub f} are experimentally separated and theoretical models of their dependencies on the overvoltage and number densities of residual charges during relaxation are suggested. Several empirical and semiempirical models are used to describe the formative time delay dependence on working voltages t{sub f} (U). The empirical and theoretical models from the literature are also applied to the experimental data, without and with empirical corrections. Moreover, several new distributions are experimentally obtained: Gauss-exponential, Gaussian and double Gaussian ones for the statistical time delay, as well as Gaussian and double Gaussian distributions for the formative time. The measurements of the breakdown time delay at different preionization levels (afterglow periods) t{sub d} ({tau}) obtained with a galvanic layer of gold and a sub-layer of nickel on the copper cathode are compared to the measurements with a vacuum deposited gold layer on the cathode surface. It was found that the surface charges retaining on a galvanic layer of gold influence the breakdown time delay which leads to double Gaussian distributions of the formative and statistical time delay.

  10. Construction delays causing risks on time and cost - a critical review

    Directory of Open Access Journals (Sweden)

    Chidambaram Ramanathan

    2012-02-01

    Full Text Available There is an increase in the number of construction projects experiencing extensive delays leading to exceeding initial time and cost budget.  This paper reviews 41 studies around the world which surveyed the delay factors and classified them into Groups.  The main purpose of this paper is to review literature, each of which have categorized the causes that are responsible for time delays and cost overrun in projects. The collected list has 113 causes for delays categorized in to 18 different groups.  Most of the researches have analysed the responses from the Questionnaire survey.    The collected data are used to rank the problem.  The data are further used to investigate and analyse Important Index, Frequency Index, Severity Index, Relative Important Index, Relative Importance Weight, Weighted Average, Mean, Standard Deviation and Variance.  The collective comparison has revealed that the ranking given by all the researchers is not the same.  Further each and every study has different rank ratings for the different group of the delays.  This review paper attempts to provide an updated compilation of the earlier studies on ranking of the delay causers, which are never similar and constant for universal projects.  It is concluded that a separate study is required for identifying the factors causing delay for projects operated in Sabah, East Malaysia.

  11. Determine separations process strategy decision

    Energy Technology Data Exchange (ETDEWEB)

    Slaathaug, E.J.

    1996-01-01

    This study provides a summary level comparative analysis of selected, top-level, waste treatment strategies. These strategies include No Separations, Separations (high-level/low-level separations), and Deferred Separations of the tank waste. These three strategies encompass the full range of viable processing alternatives based upon full retrieval of the tank wastes. The assumption of full retrieval of the tank wastes is a predecessor decision and will not be revisited in this study.

  12. Composite separators and redox flow batteries based on porous separators

    Science.gov (United States)

    Li, Bin; Wei, Xiaoliang; Luo, Qingtao; Nie, Zimin; Wang, Wei; Sprenkle, Vincent L.

    2016-01-12

    Composite separators having a porous structure and including acid-stable, hydrophilic, inorganic particles enmeshed in a substantially fully fluorinated polyolefin matrix can be utilized in a number of applications. The inorganic particles can provide hydrophilic characteristics. The pores of the separator result in good selectivity and electrical conductivity. The fluorinated polymeric backbone can result in high chemical stability. Accordingly, one application of the composite separators is in redox flow batteries as low cost membranes. In such applications, the composite separator can also enable additional property-enhancing features compared to ion-exchange membranes. For example, simple capacity control can be achieved through hydraulic pressure by balancing the volumes of electrolyte on each side of the separator. While a porous separator can also allow for volume and pressure regulation, in RFBs that utilize corrosive and/or oxidizing compounds, the composite separators described herein are preferable for their robustness in the presence of such compounds.

  13. Separating Underdetermined Convolutive Speech Mixtures

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Wang, DeLiang; Larsen, Jan

    2006-01-01

    a method for underdetermined blind source separation of convolutive mixtures. The proposed framework is applicable for separation of instantaneous as well as convolutive speech mixtures. It is possible to iteratively extract each speech signal from the mixture by combining blind source separation...

  14. Delayed umbilical cord clamping in premature neonates.

    Science.gov (United States)

    Kaempf, Joseph W; Tomlinson, Mark W; Kaempf, Andrew J; Wu, YingXing; Wang, Lian; Tipping, Nicole; Grunkemeier, Gary

    2012-08-01

    Delayed umbilical cord clamping is reported to increase neonatal blood volume. We estimated the clinical outcomes in premature neonates who had delayed umbilical cord clamping compared with a similar group who had early umbilical cord clamping. This was a before-after investigation comparing early umbilical cord clamping with delayed umbilical cord clamping (45 seconds) in two groups of singleton neonates, very low birth weight (VLBW) (401-1,500 g) and low birth weight (LBW) (greater than 1,500 g but less than 35 weeks gestation). Neonates were excluded from delayed umbilical cord clamping if they needed immediate major resuscitation. Primary outcomes were provision of delivery room resuscitation, hematocrit, red cell transfusions, and the principle Vermont Oxford Network outcomes. In VLBW neonates (77 delayed umbilical cord clamping, birth weight [mean±standard deviation] 1,099±266 g; 77 early umbilical cord clamping 1,058±289 g), delayed umbilical cord clamping was associated with less delivery room resuscitation, higher Apgar scores at 1 minute, and higher hematocrit. Delayed umbilical cord clamping was not associated with significant differences in the overall transfusion rate, peak bilirubin, any of the principle Vermont Oxford Network outcomes, or mortality. In LBW neonates (172 delayed umbilical cord clamping, birth weight [mean±standard deviation] 2,159±384 g; 172 early umbilical cord clamping 2,203±447 g), delayed umbilical cord clamping was associated with higher hematocrit and was not associated with a change in delivery room resuscitation or Apgar scores or with changes in the transfusion rate or peak bilirubin. Regression analysis showed increasing gestational age and birth weight and delayed umbilical cord clamping were the best predictors of higher hematocrit and less delivery room resuscitation. Delayed umbilical cord clamping can safely be performed in singleton premature neonates and is associated with a higher hematocrit, less delivery room

  15. General Motors sidestream separator

    Energy Technology Data Exchange (ETDEWEB)

    Tessier, R.J.

    1981-01-01

    On February 15, 1980, the United States Environmental Protection Agency, acting pursuant to Paragraph 113(D) (4) of the Clean Air Act, issued to General Motors an innovative technology order covering fifteen coal-fired spreader-stoker boilers located at six General Motors plants in Ohio. The purpose and effect of this order was to permit General Motors time to develop a new, innovative technique for controlling particulate emissions from the specified boilers before compliance with the federally approved Ohio particulate control regulation was required. This new technology was christened, The Sidestream Separator, by General Motors. It provides a highly cost effective means of reducing particulate emissions below levels currently obtainable with conventionally used high efficiency mechanical collectors. These improvements could prove to be of substantial benefit to many industrial facilities with spreader-stoker coal-fired boilers that cannot be brought into compliance with applicble air pollution regulations except by application of far more expensive and unwieldly electrostatic precipitators (ESP's) or fabric filters (baghouses).

  16. PARAFFIN SEPARATION VACUUM DISTILLATION

    Directory of Open Access Journals (Sweden)

    Zaid A. Abdulrahman

    2013-05-01

    Full Text Available Simulated column performance curves were constructed for existing paraffin separation vacuum distillation column in LAB plant (Arab Detergent Company/Baiji-Iraq. The variables considered in this study are the thermodynamic model option, top vacuum pressure, top and bottom temperatures, feed temperature, feed composition & reflux ratio. Also simulated columns profiles for the temperature, vapor & liquid flow rates composition were constructed. Four different thermodynamic model options (SRK, TSRK, PR, and ESSO were used, affecting the results within 1-25% variation for the most cases.The simulated results show that about 2% to 8 % of paraffin (C10, C11, C12, & C13 present at the bottom stream which may cause a problem in the LAB plant. The major variations were noticed for the top temperature & the  paraffin weight fractions at bottom section with top vacuum pressure. The bottom temperature above 240 oC is not recommended because the total bottom flow rate decreases sharply, where as  the weight fraction of paraffins decrease slightly. The study gives evidence about a successful simulation with CHEMCAD

  17. Beta-delayed proton emission in the 100Sn region

    CERN Document Server

    Lorusso, G; Amthor, A; Baumann, T; Bazin, D; Berryman, J S; Brown, B A; Cyburt, R H; Crawford, H L; Estrade, A; Gade, A; Ginter, T; Guess, C J; Hausmann, M; Hitt, G W; Mantica, P F; Matos, M; Meharchand, R; Minamisono, K; Montes, F; Perdikakis, G; Pereira, J; Portillo, M; Schatz, H; Smith, K; Stoker, J; Stolz, A; Zegers, R G T

    2012-01-01

    Beta-delayed proton emission from nuclides in the neighborhood of 100Sn was studied at the National Superconducting Cyclotron Laboratory. The nuclei were produced by fragmentation of a 120 MeV/nucleon 112Sn primary beam on a Be target. Beam purification was provided by the A1900 Fragment Separator and the Radio Frequency Fragment Separator. The fragments of interest were identified and their decay was studied with the NSCL Beta Counting System (BCS) in conjunction with the Segmented Germanium Array (SeGA). The nuclei 96Cd, 98Ing, 98Inm and 99In were identified as beta-delayed proton emitters, with branching ratios bp = 5.5(40)%, 5.5+3 -2%, 19(2)% and 0.9(4)%, respectively. The bp for 89Ru, 91,92Rh, 93Pd and 95Ag were deduced for the first time with bp = 3+1.9 -1.7%, 1.3(5)%, 1.9(1)%, 7.5(5)% and 2.5(3)%, respectively. The bp = 22(1)% for 101Sn was deduced with higher precision than previously reported. The impact of the newly measured bp values on the composition of the type-I X-ray burst ashes was studied.

  18. β-delayed proton emission in the 100Sn region

    Science.gov (United States)

    Lorusso, G.; Becerril, A.; Amthor, A.; Baumann, T.; Bazin, D.; Berryman, J. S.; Brown, B. A.; Cyburt, R. H.; Crawford, H. L.; Estrade, A.; Gade, A.; Ginter, T.; Guess, C. J.; Hausmann, M.; Hitt, G. W.; Mantica, P. F.; Matos, M.; Meharchand, R.; Minamisono, K.; Montes, F.; Perdikakis, G.; Pereira, J.; Portillo, M.; Schatz, H.; Smith, K.; Stoker, J.; Stolz, A.; Zegers, R. G. T.

    2012-07-01

    β-delayed proton emission from nuclides in the neighborhood of 100Sn was studied at the National Superconducting Cyclotron Laboratory (NSCL). The nuclei were produced by fragmentation of a 120 MeV/nucleon 112Sn primary beam on a Be target. Beam purification was provided by the A1900 Fragment Separator and the Radio Frequency Fragment Separator. The fragments of interest were identified and their decay was studied with the NSCL Beta Counting System in conjunction with the Segmented Germanium Array. The nuclei 96Cd, 98Ing, 98Inm, and 99In were identified as β-delayed proton emitters, with branching ratios bβp=5.5(40)%, 5.5-2+3%, 19(2)%, and 0.9(4)%, respectively. The branching ratios for 89Ru, 91,92Rh, 93Pd, and 95Ag were deduced for the first time with bβp=3-1.7+1.9%, 1.3(5)%, 1.9(1)%, 7.5(5)%, and 2.5(3)%, respectively. The bβp=22(1)% value for 101Sn was deduced with higher precision than previously reported. The impact of the newly measured bβp values on the composition of the type I x-ray burst ashes was studied.

  19. Delay Banking for Managing Air Traffic

    Science.gov (United States)

    Green, Steve

    2008-01-01

    Delay banking has been invented to enhance air-traffic management in a way that would increase the degree of fairness in assigning arrival, departure, and en-route delays and trajectory deviations to aircraft impacted by congestion in the national airspace system. In delay banking, an aircraft operator (airline, military, general aviation, etc.) would be assigned a numerical credit when any of their flights are delayed because of an air-traffic flow restriction. The operator could subsequently bid against other operators competing for access to congested airspace to utilize part or all of its accumulated credit. Operators utilize credits to obtain higher priority for the same flight, or other flights operating at the same time, or later, in the same airspace, or elsewhere. Operators could also trade delay credits, according to market rules that would be determined by stakeholders in the national airspace system. Delay banking would be administered by an independent third party who would use delay banking automation to continually monitor flights, allocate delay credits, maintain accounts of delay credits for participating airlines, mediate bidding and the consumption of credits of winning bidders, analyze potential transfers of credits within and between operators, implement accepted transfers, and ensure fair treatment of all participating operators. A flow restriction can manifest itself in the form of a delay in assigned takeoff time, a reduction in assigned airspeed, a change in the position for the aircraft in a queue of all aircraft in a common stream of traffic (e.g., similar route), a change in the planned altitude profile for an aircraft, or change in the planned route for the aircraft. Flow restrictions are typically imposed to mitigate traffic congestion at an airport or in a region of airspace, particularly congestion due to inclement weather, or the unavailability of a runway or region of airspace. A delay credit would be allocated to an operator of a

  20. Delay-dependent robust passivity control for uncertain time-delay systems

    Institute of Scientific and Technical Information of China (English)

    Li Guifang; Li Huiying; Yang Chengwu

    2007-01-01

    The robust passivity control problem is addressed for a class of uncertain delayed systems with timevarying delay. The parameter uncertainties are norm-bounded. First, the delay-dependent stability sufficient condition is obtained for the nominal system, and then, based-on the former, the delay-dependent robust passivity criteria is provided and the corresponding controller is designed in terms of linear matrix inequalities. Finally, a numerical example is given to demonstrate the validity of the proposed approach.

  1. Delay-dependent state feedback robust stabilization for uncertain singular time-delay systems

    Institute of Scientific and Technical Information of China (English)

    Gao Huanli; Xu Bugong

    2008-01-01

    The problem of robust stabilization for uncertain singular time-delay systems is studied.First,a new delay-dependent asymptotic stability criteria for normal singular time-delay systems is given,which is less conservative.Using this result,the problem of state feedback robust stabilization for uncertain singular time-delay systems is discussed.Finally,two examples are given to illustrate the effectiveness of the results.

  2. Factors in delayed muscle soreness.

    Science.gov (United States)

    Abraham, W M

    1977-01-01

    The possible causes of delayed muscle soreness which occur 24 to 48 hr after exercise were examined from three different approaches, each designed to test an existing hypothesis. Surface electromyograms were used to evaluate the muscle spasm theory; the possibility of actual muscle cell damage was monitored by the presence of myoglobinuria, while the ratio of hydroxyproline/creatinine (OHP/Cr) in 24 hr urine collection was used as a marker for connective tissue involvement. In the first study, although all volunteers developed muscle soreness 24 and 48 hr after exercise, no change in the EMG activity of the sore muscles was observed. Myoglobin excretion was found in 88% of the subjects who developed soreness. However, in a second study, 92% of the subject who performed both moderate and heavy exercise but did not develop muscle soreness had myoglobinuria. In contrast, during a third experiment subjects on gelatin-free diets showed an increase (P less than .1) in the OHP/Cr between control (.020+/-.001) and 48 hr post-exercise (.002+/-.001, X+/-SE). Soreness resulted in all cases. When the OHP/Cr value is taken for the day of maximal soreness, the post-exercise mean increases to .024+/-.001 and the level of significance rises (P less than .005). These observations support the concept that exercise induced soreness may be related to disruption of the connective tissue elements in the muscle and/or their attachments.

  3. Lactic acid delays the inflammatory response of human monocytes

    Energy Technology Data Exchange (ETDEWEB)

    Peter, Katrin, E-mail: katrin.peter@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); Rehli, Michael, E-mail: michael.rehli@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); RCI Regensburg Center for Interventional Immunology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); Singer, Katrin, E-mail: katrin.singer@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); Renner-Sattler, Kathrin, E-mail: kathrin.renner-sattler@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); Kreutz, Marina, E-mail: marina.kreutz@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); RCI Regensburg Center for Interventional Immunology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany)

    2015-02-13

    Lactic acid (LA) accumulates under inflammatory conditions, e.g. in wounds or tumors, and influences local immune cell functions. We previously noted inhibitory effects of LA on glycolysis and TNF secretion of human LPS-stimulated monocytes. Here, we globally analyze the influence of LA on gene expression during monocyte activation. To separate LA-specific from lactate- or pH-effects, monocytes were treated for one or four hours with LPS in the presence of physiological concentrations of LA, sodium lactate (NaL) or acidic pH. Analyses of global gene expression profiles revealed striking effects of LA during the early stimulation phase. Up-regulation of most LPS-induced genes was significantly delayed in the presence of LA, while this inhibitory effect was attenuated in acidified samples and not detected after incubation with NaL. LA targets included genes encoding for important monocyte effector proteins like cytokines (e.g. TNF and IL-23) or chemokines (e.g. CCL2 and CCL7). LA effects were validated for several targets by quantitative RT-PCR and/or ELISA. Further analysis of LPS-signaling pathways revealed that LA delayed the phosphorylation of protein kinase B (AKT) as well as the degradation of IκBα. Consistently, the LPS-induced nuclear accumulation of NFκB was also diminished in response to LA. These results indicate that the broad effect of LA on gene expression and function of human monocytes is at least partially caused by its interference with immediate signal transduction events after activation. This mechanism might contribute to monocyte suppression in the tumor environment. - Highlights: • Lactic acid broadly delays LPS-induced gene expression in human monocytes. • Expression of important monocyte effector molecules is affected by lactic acid. • Interference of lactic acid with TLR signaling causes the delayed gene expression. • The profound effect of lactic acid might contribute to immune suppression in tumors.

  4. Space object tracking with delayed measurements

    Science.gov (United States)

    Chen, Huimin; Shen, Dan; Chen, Genshe; Blasch, Erik; Pham, Khanh

    2010-04-01

    This paper is concerned with the nonlinear filtering problem for tracking a space object with possibly delayed measurements. In a distributed dynamic sensing environment, due to limited communication bandwidth and long distances between the earth and the satellites, it is possible for sensor reports to be delayed when the tracking filter receives them. Such delays can be complete (the full observation vector is delayed) or partial (part of the observation vector is delayed), and with deterministic or random time lag. We propose an approximate approach to incorporate delayed measurements without reprocessing the old measurements at the tracking filter. We describe the optimal and suboptimal algorithms for filter update with delayed measurements in an orbital trajectory estimation problem without clutter. Then we extend the work to a single object tracking under clutter where probabilistic data association filter (PDAF) is used to replace the recursive linear minimum means square error (LMMSE) filter and delayed measurements with arbitrary lags are be handled without reprocessing the old measurements. Finally, we demonstrate the proposed algorithms in realistic space object tracking scenarios using the NASA General Mission Analysis Tool (GMAT).

  5. ANALYSING SURFACE MOVEMENT DELAYS IN AN AIRPORT

    Directory of Open Access Journals (Sweden)

    Volodymyr Kharchenko

    2014-07-01

    Full Text Available Queuing effect can be in the different components of ground operations. Causes of surface – movement delays are long taxi – in and taxi – out operations during departure and arrival of aircraft. Surface movement delays in an airport are analyzed

  6. Minimizing the Delay at Traffic Lights

    Science.gov (United States)

    Van Hecke, Tanja

    2009-01-01

    Vehicles holding at traffic lights is a typical queuing problem. At crossings the vehicles experience delay in both directions. Longer periods with green lights in one direction are disadvantageous for the vehicles coming from the other direction. The total delay for getting through the traffic point is what counts. This article presents an…

  7. Delay synchronization of temporal Boolean networks

    Science.gov (United States)

    Wei, Qiang; Xie, Cheng-jun; Liang, Yi; Niu, Yu-jun; Lin, Da

    2016-01-01

    This paper investigates the delay synchronization between two temporal Boolean networks base on semi-tensor product method, which improve complete synchronization. Necessary and sufficient conditions for delay synchronization are drawn base on algebraic expression of temporal Boolean networks. A example is presented to show the effectiveness of theoretical analysis.

  8. Estimating Time Delays With Antenna Array

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper discusses the problem of estimating the time delays of multipath signals in wireless communications. The new multipath channel model is presented. And based on this new channel model, we generalize the classical MUSIC algorithm to estimate the time delays of multipath signals. Simulation examples are included to illustrate the algorithm performance.

  9. Comment on "Time delays in molecular photoionization"

    CERN Document Server

    Baykusheva, D

    2016-01-01

    In a recent article by P. Hockett \\textit{et al.}, time delays arising in the context of molecular single-photon ionization are investigated from a theoretical point of view. We argue that one of the central equations derived in the paper is incorrect and present a reformulation that is consistent with the established treatment of angle-dependent scattering delays.

  10. Broadband hyperchaotic oscillator with delay line

    DEFF Research Database (Denmark)

    Cenys, Antanas; Lindberg, Erik; Anagnostopoulos, A. N.;

    2002-01-01

    Dynamical systems with time delay can be employed as high dimensional hyperchaotic oscillators with multiple positive Lyapunov exponents. We describe an electronic circuit composed of a 3-stage amplifier and a delay line in the feedback loop. The 1st stage of the amplifier is a nonlinear one while...

  11. Controllability of delay systems with restrained controls

    Science.gov (United States)

    Chukwu, E. N.

    1979-01-01

    Using a geometric growth condition, both the function space and Euclidean controllability of a nonlinear delay system which has a compact and convex control set are characterized. This extends analogous results for ordinary differential systems, and it yields conditions under which perturbed nonlinear delay controllable systems are controllable.

  12. Diagnostic Delay in Women with Endometriosis

    Institute of Scientific and Technical Information of China (English)

    Xiao-man Ding; Jing-he Lang

    2005-01-01

    @@ Women affected by endometriosis claim that delayed diagnosis of endometriosis is a great problem. Studies have shown a delay from 3 to 11 years between the onset of pain symptom and the final diagnosis of endometriosis. But the diagnostic time of Chinese patients has not been reported.

  13. Test Anxiety and Academic Delay of Gratification

    Science.gov (United States)

    Bembenutty, Hefer

    2009-01-01

    The present study examined the relationship between college students' willingness to delay gratification, motivation, self-regulation of learning, and their level of test anxiety (N = 364). Academic delay of gratification refers to students' postponement of immediately available opportunities to satisfy impulses in favor of pursuing academic…

  14. [Delayed asthma bronchiale due to epoxy resin].

    Science.gov (United States)

    Authried, Georg; Al-Asadi, Haifaa; Møller, Ulla; Sherson, David Lee

    2013-10-28

    Epoxy resin is a low molecular weight agent, which can cause both acute and delayed allergic reactions. However, it is known causing skin reactions with direct or airborne contact. Rarely it can cause airway reactions like asthma bronchiale. We describe a case of a windmill worker who developed delayed asthma bronchiale due to airborne contact with epoxy resin.

  15. Analyzing delay causes in Egyptian construction projects

    Directory of Open Access Journals (Sweden)

    Mohamed M. Marzouk

    2014-01-01

    Full Text Available Construction delays are common problems in civil engineering projects in Egypt. These problems occur frequently during project life-time leading to disputes and litigation. Therefore, it is essential to study and analyze causes of construction delays. This research presents a list of construction delay causes retrieved from literature. The feedback of construction experts was obtained through interviews. Subsequently, a questionnaire survey was prepared. The questionnaire survey was distributed to thirty-three construction experts who represent owners, consultants, and contractor’s organizations. Frequency Index, Severity Index, and Importance Index are calculated and according to the highest values of them the top ten delay causes of construction projects in Egypt are determined. A case study is analyzed and compared to the most important delay causes in the research. Statistical analysis is carried out using analysis of variance ANOVA method to test delay causes, obtained from the survey. The test results reveal good correlation between groups while there is significant difference between them for some delay causes and finally roadmap for prioritizing delay causes groups is presented.

  16. Analyzing delay causes in Egyptian construction projects.

    Science.gov (United States)

    Marzouk, Mohamed M; El-Rasas, Tarek I

    2014-01-01

    Construction delays are common problems in civil engineering projects in Egypt. These problems occur frequently during project life-time leading to disputes and litigation. Therefore, it is essential to study and analyze causes of construction delays. This research presents a list of construction delay causes retrieved from literature. The feedback of construction experts was obtained through interviews. Subsequently, a questionnaire survey was prepared. The questionnaire survey was distributed to thirty-three construction experts who represent owners, consultants, and contractor's organizations. Frequency Index, Severity Index, and Importance Index are calculated and according to the highest values of them the top ten delay causes of construction projects in Egypt are determined. A case study is analyzed and compared to the most important delay causes in the research. Statistical analysis is carried out using analysis of variance ANOVA method to test delay causes, obtained from the survey. The test results reveal good correlation between groups while there is significant difference between them for some delay causes and finally roadmap for prioritizing delay causes groups is presented.

  17. Stabilization of a Nonlinear Delay System

    Directory of Open Access Journals (Sweden)

    Walid Arouri

    2012-01-01

    Full Text Available Problem statement: The analysis and control of delayed systems are becoming more and more research topics in progress. This is mainly due to the fact that the delay is frequently encountered in technological systems. This can affect their significantly operations. Most control command laws are based on current digital computers and delays are intrinsic to the process or in the control loop caused by the transmission time control sequences, or computing time. The delay may affect one or more states of the considered system. It may also affect the establishment of the command. Several studies have investigated the stability of delay systems under the assumption that the delay is a variable phenomenon; such variation is considered to be bounded or limited to facilitate analysis of the system. In this study we propose a modelling of delayed system by using the multimodels and switched system theory. The analysis of stability is based on the use of second Lyapunov method. The issued stability conditions are expressed as Bilinear Matrix Inequalities impossible to resolve. That’s why we propose the same original relaxations to come over this difficulty, an example of induction machine is given to illustrate over approach. Approach: We propose to use the control theory developed for switched systems to synthesis a control laws for the stabilisation of delays system. Results: We stabilize the induction machine around many operating points despite the non linearities. Conclusion: The developed method is less conservative and less pessimistic than the used classical methods.

  18. Delayed biodiversity change: no time to waste.

    Science.gov (United States)

    Essl, Franz; Dullinger, Stefan; Rabitsch, Wolfgang; Hulme, Philip E; Pyšek, Petr; Wilson, John R U; Richardson, David M

    2015-07-01

    Delayed biodiversity responses to environmental forcing mean that rates of contemporary biodiversity changes are underestimated, yet these delays are rarely addressed in conservation policies. Here, we identify mechanisms that lead to such time lags, discuss shifting human perceptions, and propose how these phenomena should be addressed in biodiversity management and science.

  19. Congenital rubella syndrome and delayed manifestations

    DEFF Research Database (Denmark)

    Dammeyer, Jesper Herup

    2010-01-01

    Objective: Several hypotheses of different medical and psychological delayed manifestations among people who have congenital rubella syndrome (CRS) have been discussed. This study tests some of these hypotheses of delayed manifestations. Methods: Gathering information about 35 individuals who hav...... which people with CRS face must primarily be understood in relation to congenital deafblindness and dual sensory and communicative deprivation....

  20. Discounting of Delayed Rewards Is Not Hyperbolic

    Science.gov (United States)

    Luhmann, Christian C.

    2013-01-01

    Delay discounting refers to decision-makers' tendency to value immediately available goods more than identical goods available only after some delay. In violation of standard economic theory, decision-makers frequently exhibit dynamic inconsistency; their preferences change simply due to the passage of time. The standard explanation for this…

  1. On Delay and Security in Network Coding

    Science.gov (United States)

    Dikaliotis, Theodoros K.

    2013-01-01

    In this thesis, delay and security issues in network coding are considered. First, we study the delay incurred in the transmission of a fixed number of packets through acyclic networks comprised of erasure links. The two transmission schemes studied are routing with hop-by-hop retransmissions, where every node in the network simply stores and…

  2. Improved delay-dependent exponential stability for uncertain stochastic neural networks with time-varying delays

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, O.M., E-mail: madwind@chungbuk.ac.k [School of Electrical Engineering, Chungbuk National University, Cheongju (Korea, Republic of); Lee, S.M., E-mail: moony@daegu.ac.k [School of Electronics Engineering, Daegu University, Kyongsan (Korea, Republic of); Park, Ju H., E-mail: jessie@ynu.ac.k [Department of Electrical Engineering, Yeungnam University, Kyongsan (Korea, Republic of)

    2010-02-22

    This Letter investigates the problem of delay-dependent exponential stability analysis for uncertain stochastic neural networks with time-varying delay. Based on the Lyapunov stability theory, improved delay-dependent exponential stability criteria for the networks are established in terms of linear matrix inequalities (LMIs).

  3. Shark Skin Bristling as a Passive Mechanism for Separation Control

    Science.gov (United States)

    Wheelus, Jennifer; Lang, Amy; Jones, Emily

    2011-11-01

    The skin of fast-swimming sharks is proposed to have mechanisms to reduce drag and delay flow separation. The skin of fast-swimming and agile sharks is covered with small teeth-like denticles on the order of 0.2 mm. The shortfin mako is one of the fastest and most agile ocean predators creating the need to minimize its pressure drag by controlling flow separation. Biological studies of the shortfin mako skin have shown the passive bristling angle of their denticles to exceed 50 degrees in areas on the flank corresponding to the locations likely to experience separation first. It is proposed that reversing flow, as occurs at the onset of separation in a turbulent boundary layer, would activate denticle bristling and hinder local separation from leading to global separation over the shark. This study focuses on the denticle reaction to various reversed flow conditions using a pulsating jet. Mako shark skin was subjected to numerous reversed flow velocities to determine the bristling onset velocity. Digital Particle Image Velocimetry (DPIV) and digital video were used to determine the flow conditions and denticle behavior. The effect of reversed flow velocity on denticle bristling and its relation to separation control will be discussed. Research funded by NSF (award 0932352).

  4. Delay in the diagnosis of cancer

    DEFF Research Database (Denmark)

    Hansen, Rikke Pilegaard

    of delay is described and an operational definition and a review of the literature of delay are presented. Then follows a description of the methods for assessing delay and the results of a descriptive study of delay (Article 1) and three studies of the associations between delay and patients...... for a detailed description of the patients' diagnostic pathways, allowing the researchers to draw the time line from symptom onset to treatment start, and to describe the characteristics of the patients and the GPs. Existing scales were used whenever possible; otherwise, ad hoc questions were constructed...... in the study. The chapter addresses issues of data and study validity, and the precision of the study. Data validity is discussed in relation to study design, data collection, data quality and statistical analyses. Study validity is discussed in terms of precision, and internal and external validity...

  5. Photonic Quantum Circuits with Time Delays

    CERN Document Server

    Pichler, Hannes

    2015-01-01

    We study the dynamics of photonic quantum circuits consisting of nodes coupled by quantum channels. We are interested in the regime where time delay in communication between the nodes is significant. This includes the problem of quantum feedback, where a quantum signal is fed back on a system with a time delay. We develop a matrix product state approach to solve the Quantum Stochastic Schr\\"odinger Equation with time delays, which accounts in an efficient way for the entanglement of nodes with the stream of emitted photons in the waveguide, and thus the non-Markovian character of the dynamics. We illustrate this approach with two paradigmatic quantum optical examples: two coherently driven distant atoms coupled to a photonic waveguide with a time delay, and a driven atom coupled to its own output field with a time delay as an instance of a quantum feedback problem.

  6. Stochastic thermodynamics for delayed Langevin systems.

    Science.gov (United States)

    Jiang, Huijun; Xiao, Tiejun; Hou, Zhonghuai

    2011-06-01

    We discuss stochastic thermodynamics (ST) for delayed Langevin systems in this paper. By using the general principles of ST, the first-law-like energy balance and trajectory-dependent entropy s(t) can be well defined in a way that is similar to that in a system without delay. Because the presence of time delay brings an additional entropy flux into the system, the conventional second law (Δs(tot))≥0 no longer holds true, where Δs(tot) denotes the total entropy change along a stochastic path and (·) stands for the average over the path ensemble. With the help of a Fokker-Planck description, we introduce a delay-averaged trajectory-dependent dissipation functional η[χ(t)] which involves the work done by a delay-averaged force F(x,t) along the path χ(t) and equals the medium entropy change Δs(m)[x(t)] in the absence of delay. We show that the total dissipation functional R=Δs+η, where Δs denotes the system entropy change along a path, obeys (R)≥0, which could be viewed as the second law in the delayed system. In addition, the integral fluctuation theorem (e(-R))=1 also holds true. We apply these concepts to a linear Langevin system with time delay and periodic external force. Numerical results demonstrate that the total entropy change (Δs(tot)) could indeed be negative when the delay feedback is positive. By using an inversing-mapping approach, we are able to obtain the delay-averaged force F(x,t) from the stationary distribution and then calculate the functional R as well as its distribution. The second law (R)≥0 and the fluctuation theorem are successfully validated.

  7. Delayed feedback during sensorimotor learning selectively disrupts adaptation but not strategy use.

    Science.gov (United States)

    Brudner, Samuel N; Kethidi, Nikhit; Graeupner, Damaris; Ivry, Richard B; Taylor, Jordan A

    2016-03-01

    In sensorimotor adaptation tasks, feedback delays can cause significant reductions in the rate of learning. This constraint is puzzling given that many skilled behaviors have inherently long delays (e.g., hitting a golf ball). One difference in these task domains is that adaptation is primarily driven by error-based feedback, whereas skilled performance may also rely to a large extent on outcome-based feedback. This difference suggests that error- and outcome-based feedback may engage different learning processes, and these processes may be associated with different temporal constraints. We tested this hypothesis in a visuomotor adaptation task. Error feedback was indicated by the terminal position of a cursor, while outcome feedback was indicated by points. In separate groups of participants, the two feedback signals were presented immediately at the end of the movement, after a delay, or with just the error feedback delayed. Participants learned to counter the rotation in a similar manner regardless of feedback delay. However, the aftereffect, an indicator of implicit motor adaptation, was attenuated with delayed error feedback, consistent with the hypothesis that a different learning process supports performance under delay. We tested this by employing a task that dissociates the contribution of explicit strategies and implicit adaptation. We find that explicit aiming strategies contribute to the majority of the learning curve, regardless of delay; however, implicit learning, measured over the course of learning and by aftereffects, was significantly attenuated with delayed error-based feedback. These experiments offer new insight into the temporal constraints associated with different motor learning processes.

  8. Delay-dependent observer-based stabilizing controller design for linear multiple state-delayed systems

    Institute of Scientific and Technical Information of China (English)

    Dejin WANG

    2003-01-01

    This article concerns a coupled LMIs approach to delay-dependent observer-based output feedback stabilizing controller design for linear continuous-time systems with multiple state delays. The advantage of our proposed delay-dependent coupled LMIs criterion lies in that: (1) it can optimize one of multiple time delays with others selected properly, and at the same time, the feedback-gain and observer-gain can be obtained, respectively. (2) it is less conservative than the existing delay-independent ones in the literature. Algorithm to solve the coupled LMIs is also given. Numerical examples illustrate the effectiveness of our method.

  9. Isochronal synchronization of time delay and delay-coupled chaotic systems

    Energy Technology Data Exchange (ETDEWEB)

    Grzybowski, J M V; Yoneyama, T [Instituto Tecnologico de Aeronautica, ITA, Praca Marechal Eduardo Gomes, 50, Vila das Acacias, Sao Jose dos Campos, SP, Brazil, CEP 12.228-900 (Brazil); Macau, E E N, E-mail: zzmariovic@yahoo.com.br, E-mail: elbert@lac.inpe.br, E-mail: takashi@ita.br [Instituto Nacional de Pesquisas Espaciais, INPE, PO Box 515, Sao Jose dos Campos, SP, Brazil, CEP 12.227-010 (Brazil)

    2011-04-29

    This paper studies the problem of isochronal synchronization of time-delay chaotic systems featuring also coupling delay. Based on the Lyapunov-Krasovskii stability theory, sufficient conditions are derived for the stability of isochronal synchronization between a pair of identical chaotic systems. Such criteria permit the proper design of stable proportional linear feedback controller, more specifically, the design of adequate proportional feedback gain matrices. The proposed criteria are suited to systems with (i) intrinsic delay, (ii) coupling delay or (iii) both. Numerical simulations of the synchronization of delay-coupled systems are presented as examples of the application of the criteria.

  10. DNA damage leads to a Cyclin A-dependent delay in metaphase-anaphase transition in the Drosophila gastrula.

    Science.gov (United States)

    Su, T T; Jaklevic, B

    2001-01-09

    In response to DNA damage, fission yeast, mammalian cells, and cells of the Drosophila gastrula inhibit Cdk1 to delay the entry into mitosis. In contrast, budding yeast delays metaphase-anaphase transition by stabilization of an anaphase inhibitor, Pds1p. A variation of the second response is seen in Drosophila cleavage embryos; when nuclei enter mitosis with damaged DNA, centrosomes lose gamma-tubulin, spindles lose astral microtubules, chromosomes fail to reach a metaphase configuration, and interphase resumes without an intervening anaphase. The resulting polyploid nuclei are eliminated. The cells of the Drosophila gastrula can also delay metaphase-anaphase transition in response to DNA damage. This delay accompanies the stabilization of Cyclin A, a known inhibitor of sister chromosome separation in Drosophila. Unlike in cleavage embryos, gamma-tubulin remains at the spindle poles, and anaphase always occurs after the delay. Cyclin A mutants fail to delay metaphase-anaphase transition after irradiation and show an increased frequency of chromosome breakage in the subsequent anaphase. DNA damage delays metaphase-anaphase transition in Drosophila by stabilizing Cyclin A. This delay may normally serve to preserve chromosomal integrity during segregation. To our knowledge this is the first report of a metazoan metaphase-anaphase transition being delayed in response to DNA damage. Though mitotic progression is modulated in response to DNA damage in both cleaving and gastruating embryos of Drosophila, different mechanisms operate. These differences are discussed in the context of differential cell cycle regulation in cleavage and gastrula stages.

  11. High temperature inorganic membranes for separating hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Fain, D.E.; Roettger, G.E. [Oak Ridge K-25 Site, TN (United States)

    1995-08-01

    Effort has continued to accumulate data on the transport of gases over the temperature range from room temperature to 275{degrees}C with inorganic membranes having a range of pore radii from approximately 0.25 nm to 3 mn. An experimental alumina membrane having an estimated mean pore radius of 0.25 nm has been fabricated and tested. Extensive testing of this membrane indicated that the separation factor for helium and carbon tetrafluoride at 250{degrees}C was 59 and the extrapolated high temperature separation factor was 1,193. For safety reasons, earlier flow measurements concentrated on helium, carbon dioxide, and carbon tetrafluoride. New data have been acquired with hydrogen to verify the agreement with the other gases. During the measurements with hydrogen, it was noted that a considerable amount of moisture was present in the test gas. The source of this moisture and its effect on permeance was examined. Improvements were implemented to the flow test system to minimize the water content of the hydrogen test gas, and subsequent flow measurements have shown excellent results with hydrogen. The extrapolation of separation factors as a function of temperature continues to show promise as a means of using the hard sphere model to determine the pore size of membranes. The temperature dependence of helium transport through membranes appears to be considerably greater than other gases for the smallest pore sizes. The effort to extend temperature dependence to the hard sphere model continues to be delayed, primarily because of a lack of adequate adsorption data.

  12. A novel approach to delay-fractional-dependent stability criterion for linear systems with interval delay.

    Science.gov (United States)

    An, Jiyao; Li, Zhiyong; Wang, Xiaomei

    2014-03-01

    This paper considers the problem of delay-fractional-dependent stability analysis of linear systems with interval time-varying state delay. By developing a delay variable decomposition approach, both the information of the variable dividing subinterval delay, and the information of the lower and upper bound of delay can be taken into full consideration. Then a new delay-fractional-dependent stability criterion is derived without involving any direct approximation in the time-derivative of the Lyapunov-Krasovskii (LK) functional via some suitable Jensen integral inequalities and convex combination technique. The merits of the proposed result lie in less conservatism, which are realized by choosing different Lyapunov matrices in the variable delay subintervals and estimating the upper bound of some cross term in LK functional more exactly. At last, two well-known numerical examples are employed to show the effectiveness and less conservatism of the proposed method.

  13. Orthodontic Elastic Separator-Induced Periodontal Abscess: A Case Report

    Directory of Open Access Journals (Sweden)

    Talia Becker

    2012-01-01

    Full Text Available Aim. Orthodontic elastic bands were proposed as being the source of gingival abscesses that can rapidly lead to bone loss and teeth exfoliation. We report an adolescent, otherwise, healthy patient whose periodontal status was sound. Shortly after undergoing preparations for orthodontic treatment consisting of orthodontic separators, he presented with a periodontal abscess for which there was no apparent etiology. A non-orthoradial X-ray was inconclusive, but an appropriate one revealed a subgingival orthodontic separator as the cause of the abscess. Removal of the separator and thorough scaling led to complete resolution of the abscess, but there was already residual mild damage to the alveolar bone. Summary. Failure to use appropriate imaging to reveal the cause of gingival abscesses can result in the delay of implementing treatment and halting irreversible alveolar bone loss. An inflammatory process restricted to the gingiva and refractive to conventional therapy should raise the possibility of a foreign body etiology.

  14. Broadband true time delay for microwave signal processing, using slow light based on stimulated Brillouin scattering in optical fibers.

    Science.gov (United States)

    Chin, Sanghoon; Thévenaz, Luc; Sancho, Juan; Sales, Salvador; Capmany, José; Berger, Perrine; Bourderionnet, Jérôme; Dolfi, Daniel

    2010-10-11

    We experimentally demonstrate a novel technique to process broadband microwave signals, using all-optically tunable true time delay in optical fibers. The configuration to achieve true time delay basically consists of two main stages: photonic RF phase shifter and slow light, based on stimulated Brillouin scattering in fibers. Dispersion properties of fibers are controlled, separately at optical carrier frequency and in the vicinity of microwave signal bandwidth. This way time delay induced within the signal bandwidth can be manipulated to correctly act as true time delay with a proper phase compensation introduced to the optical carrier. We completely analyzed the generated true time delay as a promising solution to feed phased array antenna for radar systems and to develop dynamically reconfigurable microwave photonic filters.

  15. Delayed diagnosis of narcolepsy: characterization and impact.

    Science.gov (United States)

    Thorpy, Michael J; Krieger, Ana C

    2014-05-01

    Narcolepsy, a chronic neurologic condition resulting from dysregulation of the sleep-wake cycle, usually has an onset at an early age. However, a long delay until diagnosis has been consistently reported in the literature across countries and several publications have focused on characterizing this delay. Most studies report a mean delay to diagnosis of up to 15 years, with individual cases of >60 years, although a trend over time toward a shorter diagnostic delay has been suggested. While variables associated with this delay have been identified, a lack of symptom recognition resulting in misdiagnosis prior to reaching the narcolepsy diagnosis is the likely underlying reason. This lack of symptom recognition is especially relevant considering the high comorbidity burden that has been shown in patients with narcolepsy as some disorders manifest with symptoms that overlap with narcolepsy. A consequence of delayed diagnosis is delayed treatment, which affects the burden of disease. Substantial detrimental effects on health-care resource utilization, employment, and quality of life have been described after narcolepsy onset and prior to the diagnosis of narcolepsy. This review highlights the importance of closing the diagnostic gap by expanding awareness of narcolepsy and its symptoms.

  16. Spin-orbit delays in photoemission

    Science.gov (United States)

    Jordan, I.; Huppert, M.; Pabst, S.; Kheifets, A. S.; Baykusheva, D.; Wörner, H. J.

    2017-01-01

    Attosecond delays between photoelectron wave packets emitted from different electronic shells are now well established. Is there any delay between electrons originating from the same electronic shell but leaving the cation in different fine-structure states? This question is relevant for all attosecond photoemission studies involving heavy elements, be it atoms, molecules or solids. We answer this fundamental question by measuring energy-dependent delays between photoelectron wave packets associated with the 3/2 2P and 1/2 2P components of the electronic ground states of Xe+ and Kr+. We observe delays reaching up to 33 ±6 as in the case of Xe. Our results are compared with two state-of-the-art theories. Whereas both theories quantitatively agree with the results obtained for Kr, neither of them fully reproduces the experimental results in Xe. Performing delay measurements very close to the ionization thresholds, we compare the agreement of several analytical formulas for the continuum-continuum delays with experimental data. Our results show an important influence of spin-orbit coupling on attosecond photoionization delays, highlight the requirement for additional theory development, and offer a precision benchmark for such work.

  17. Delays in Building Construction Projects in Ghana

    Directory of Open Access Journals (Sweden)

    Adwoa B Agyakwah-Baah

    2010-07-01

    Full Text Available This study investigates the causes of delay of building construction projects in Ghana to determine the most important according to the key project participants; clients, consultants, and contractors. Thirty-two possible causes of delay were identified from the literature and semi-structured interviews of 15 key players in the implementation process. These delay factors were further categorised into nine major groups. The list of delay causes was subjected to a questionnaire survey for the identification of the most important causes of delay. The field survey included 130 respondents made up of 39 contractors, 37 clients and 54 consultants. The relative importance of the individual causes and the groups were calculated and ranked by their relative importance index. The overall results of the study indicate that the respondents generally agree that financial group factors ranked highest among the major factors causing delay in construction projects in Ghana. The financial group factors were delay in honouring payment certificates, difficulty in accessing credit and fluctuation in prices. Materials group factors are second followed by scheduling and controlling factors.

  18. Separators - Technology review: Ceramic based separators for secondary batteries

    Science.gov (United States)

    Nestler, Tina; Schmid, Robert; Münchgesang, Wolfram; Bazhenov, Vasilii; Schilm, Jochen; Leisegang, Tilmann; Meyer, Dirk C.

    2014-06-01

    Besides a continuous increase of the worldwide use of electricity, the electric energy storage technology market is a growing sector. At the latest since the German energy transition ("Energiewende") was announced, technological solutions for the storage of renewable energy have been intensively studied. Storage technologies in various forms are commercially available. A widespread technology is the electrochemical cell. Here the cost per kWh, e. g. determined by energy density, production process and cycle life, is of main interest. Commonly, an electrochemical cell consists of an anode and a cathode that are separated by an ion permeable or ion conductive membrane - the separator - as one of the main components. Many applications use polymeric separators whose pores are filled with liquid electrolyte, providing high power densities. However, problems arise from different failure mechanisms during cell operation, which can affect the integrity and functionality of these separators. In the case of excessive heating or mechanical damage, the polymeric separators become an incalculable security risk. Furthermore, the growth of metallic dendrites between the electrodes leads to unwanted short circuits. In order to minimize these risks, temperature stable and non-flammable ceramic particles can be added, forming so-called composite separators. Full ceramic separators, in turn, are currently commercially used only for high-temperature operation systems, due to their comparably low ion conductivity at room temperature. However, as security and lifetime demands increase, these materials turn into focus also for future room temperature applications. Hence, growing research effort is being spent on the improvement of the ion conductivity of these ceramic solid electrolyte materials, acting as separator and electrolyte at the same time. Starting with a short overview of available separator technologies and the separator market, this review focuses on ceramic-based separators

  19. Mathematical modelling of membrane separation

    DEFF Research Database (Denmark)

    Vinther, Frank

    This thesis concerns mathematical modelling of membrane separation. The thesis consists of introductory theory on membrane separation, equations of motion, and properties of dextran, which will be the solute species throughout the thesis. Furthermore, the thesis consist of three separate mathemat......This thesis concerns mathematical modelling of membrane separation. The thesis consists of introductory theory on membrane separation, equations of motion, and properties of dextran, which will be the solute species throughout the thesis. Furthermore, the thesis consist of three separate....... It is found that the probability of entering the pore is highest when the largest of the radii in the ellipse is equal to half the radius of the pore, in case of molecules with circular radius less than the pore radius. The results are directly related to the macroscopic distribution coefficient...

  20. Capillary Separation: Micellar Electrokinetic Chromatography

    Science.gov (United States)

    Terabe, Shigeru

    2009-07-01

    Micellar electrokinetic chromatography (MEKC), a separation mode of capillary electrophoresis (CE), has enabled the separation of electrically neutral analytes. MEKC can be performed by adding an ionic micelle to the running solution of CE without modifying the instrument. Its separation principle is based on the differential migration of the ionic micelles and the bulk running buffer under electrophoresis conditions and on the interaction between the analyte and the micelle. Hence, MEKC's separation principle is similar to that of chromatography. MEKC is a useful technique particularly for the separation of small molecules, both neutral and charged, and yields high-efficiency separation in a short time with minimum amounts of sample and reagents. To improve the concentration sensitivity of detection, several on-line sample preconcentration techniques such as sweeping have been developed.

  1. Separable programming theory and methods

    CERN Document Server

    Stefanov, Stefan M

    2001-01-01

    In this book, the author considers separable programming and, in particular, one of its important cases - convex separable programming Some general results are presented, techniques of approximating the separable problem by linear programming and dynamic programming are considered Convex separable programs subject to inequality equality constraint(s) and bounds on variables are also studied and iterative algorithms of polynomial complexity are proposed As an application, these algorithms are used in the implementation of stochastic quasigradient methods to some separable stochastic programs Numerical approximation with respect to I1 and I4 norms, as a convex separable nonsmooth unconstrained minimization problem, is considered as well Audience Advanced undergraduate and graduate students, mathematical programming operations research specialists

  2. Separation process using microchannel technology

    Science.gov (United States)

    Tonkovich, Anna Lee; Perry, Steven T.; Arora, Ravi; Qiu, Dongming; Lamont, Michael Jay; Burwell, Deanna; Dritz, Terence Andrew; McDaniel, Jeffrey S.; Rogers, Jr.; William A.; Silva, Laura J.; Weidert, Daniel J.; Simmons, Wayne W.; Chadwell, G. Bradley

    2009-03-24

    The disclosed invention relates to a process and apparatus for separating a first fluid from a fluid mixture comprising the first fluid. The process comprises: (A) flowing the fluid mixture into a microchannel separator in contact with a sorption medium, the fluid mixture being maintained in the microchannel separator until at least part of the first fluid is sorbed by the sorption medium, removing non-sorbed parts of the fluid mixture from the microchannel separator; and (B) desorbing first fluid from the sorption medium and removing desorbed first fluid from the microchannel separator. The process and apparatus are suitable for separating nitrogen or methane from a fluid mixture comprising nitrogen and methane. The process and apparatus may be used for rejecting nitrogen in the upgrading of sub-quality methane.

  3. Wastewater treatment with acoustic separator

    Science.gov (United States)

    Kambayashi, Takuya; Saeki, Tomonori; Buchanan, Ian

    2017-07-01

    Acoustic separation is a filter-free wastewater treatment method based on the forces generated in ultrasonic standing waves. In this report, a batch-system separator based on acoustic separation was demonstrated using a small-scale prototype acoustic separator to remove suspended solids from oil sand process-affected water (OSPW). By applying an acoustic separator to the batch use OSPW treatment, the required settling time, which was the time that the chemical oxygen demand (COD) decreased to the environmental criterion (<200 mg/L), could be shortened from 10 to 1 min. Moreover, for a 10 min settling time, the acoustic separator could reduce the FeCl3 dose as coagulant in OSPW treatment from 500 to 160 mg/L.

  4. Delay-dependent robust H∞ controller design for a class of nonlinear uncertainty time-delay systems with input delay

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Based on an appropriate Lyapunov function,this paper analyzes the design of a delay-dependent robust H∞ state feedback control,with a focus on a class of non linear uncertainty linear time-delay systems with input delay using linear matrix inequalities.Under the condition that the nonlinear uncertain functions are gain bounded,a sufficient condition dependent on the delays of the state and input is presented for the existence of H∞ controller.The proposed controller not only stabilized closed-loop uncertain systems but also guaranteed a prescribed H∞ norm bound of closed-loop transfer matrix from the disturbance to controlled output.By solving a linear matrix inequation,we can obtain the robust H∞ controller.An example is given to show the effectiveness of the proposed method.

  5. Hereditary separability in Hausdorff continua

    Directory of Open Access Journals (Sweden)

    D. Daniel

    2012-04-01

    Full Text Available We consider those Hausdorff continua S such that each separable subspace of S is hereditarily separable. Due to results of Ostaszewski and Rudin, respectively, all monotonically normal spaces and therefore all continuous Hausdorff images of ordered compacta also have this property. Our study focuses on the structure of such spaces that also possess one of various rim properties, with emphasis given to rim-separability. In so doing we obtain analogues of results of M. Tuncali and I. Loncar, respectively.

  6. ON FEEDBACK CONTROL OF DELAYED CHAOTIC SYSTEM

    Institute of Scientific and Technical Information of China (English)

    李丽香; 彭海朋; 卢辉斌; 关新平

    2001-01-01

    In this paper two different types of feedback control technique are discussed: the standard feedback control and the time-delay feedback control which have been successfully used in many control systems. In order to understand to what extent the two different types of control technique are useful in delayed chaotic systems, some analytic stabilization conditions for chaos control from the two types of control technique are derived based on Lyapunov stabilization arguments. Similarly, we discuss the tracking problem by applying the time-delay feedback control. Finally, numerical examples are provided.

  7. Delayed self-synchronization in homoclinic chaos

    Science.gov (United States)

    Arecchi, F. T.; Meucci, R.; Allaria, E.; di Garbo, A.; Tsimring, L. S.

    2002-04-01

    The chaotic spike train of a homoclinic dynamical system is self-synchronized by applying a time-delayed correction proportional to the laser output intensity. Due to the sensitive nature of the homoclinic chaos to external perturbations, stabilization of very long-periodic orbits is possible. On these orbits, the dynamics appears chaotic over a finite time, but then it repeats with a recurrence time that is slightly longer than the delay time. The effect, called delayed self-synchronization, displays analogies with neurodynamic events that occur in the buildup of long-term memories.

  8. Statistical Elmore delay of RC interconnect tree

    Institute of Scientific and Technical Information of China (English)

    Dong Gang; Yang Yang; Chai Chang-Chun; Yang Yin-Tang

    2010-01-01

    As feature size keeps scaling down, process variations can dramatically reduce the accuracy in the estimation of interconnect performance. This paper proposes a statistical Elmore delay model for RC interconnect tree in the presence of process variations. The suggested method translates the process variations into parasitic parameter extraction and statistical Elmore delay evaluation. Analytical expressions of mean and standard deviation of interconnect delay can be obtained in a given fluctuation range of interconnect geometric parameters. Experimental results demonstrate that the approach matches well with Monte Carlo simulations. The errors of proposed mean and standard deviation are less than 1% and 7%, respectively. Simulations prove that our model is efficient and accurate.

  9. Transcriptional delay stabilizes bistable gene networks

    Science.gov (United States)

    Gupta, Chinmaya; López, José Manuel; Ott, William; Josić, Krešimir; Bennett, Matthew R.

    2014-01-01

    Transcriptional delay can significantly impact the dynamics of gene networks. Here we examine how such delay affects bistable systems. We investigate several stochastic models of bistable gene networks and find that increasing delay dramatically increases the mean residence times near stable states. To explain this, we introduce a non-Markovian, analytically tractable reduced model. The model shows that stabilization is the consequence of an increased number of failed transitions between stable states. Each of the bistable systems that we simulate behaves in this manner. PMID:23952450

  10. Technical Progress of China's Delayed Coking Technology

    Institute of Scientific and Technical Information of China (English)

    Zhang Lixin; Li Hejie

    2005-01-01

    This article introduces the recent advances of China in the fields of process technology of delayed coking, enlarged equipment size, hydraulic decoking, automatic control and environmental protection. By the end of 2004 the total capacity of delayed coking units in China had reached 37.24Mt/a with the maximum coke drum diameter equating to 9.4 m. This article also presents the investment in delayed cokers and the current production status while pointing out the existing problems and future development trends.

  11. Synchronisation of time-delay systems

    CERN Document Server

    Bünner, M J; Bünner, Martin J.; Just, Wolfram

    1998-01-01

    We present the linear-stability analysis of synchronised states in coupled time-delay systems. There exists a synchronisation threshold, for which we derive upper bounds, which does not depend on the delay time. We prove that at least for scalar time-delay systems synchronisation is achieved by transmitting a single scalar signal, even if the synchronised solution is given by a high-dimensional chaotic state with a large number of positive Lyapunov-exponents. The analytical results are compared with numerical simulations of two coupled Mackey-Glass equations.

  12. Delayed encephalopathy after acute carbon monoxide poisoning

    Directory of Open Access Journals (Sweden)

    Mehmet İbrahim Turan

    2014-03-01

    Full Text Available Carbon monoxide poisoning is a major cause of death following attempted suicide and accidental exposures. Although clinical presentation depends on the duration and the intensity of exposure, the assessment of the severity of intoxication is difficult. A small percentage of patients who show complete initial recovery may develop delayed neurological deficits. Delayed encephalopathy after acute carbon monoxide poisoning is a rare and poor prognosis neurologic disorders and there is no specific treatment. We present a case with early onset of delayed encephalopathy after acute carbon monoxide poisoning with typical cranial imaging findings in a child with atypical history and clinical presentation.

  13. Recovery of couplings and parameters of elements in networks of time-delay systems from time series

    Science.gov (United States)

    Sysoev, I. V.; Ponomarenko, V. I.; Kulminskiy, D. D.; Prokhorov, M. D.

    2016-11-01

    We propose a method for the recovery of coupling architecture and the parameters of elements in networks consisting of coupled oscillators described by delay-differential equations. For each oscillator in the network, we introduce an objective function characterizing the distance between the points of the reconstructed nonlinear function. The proposed method is based on the minimization of this objective function and the separation of the recovered coupling coefficients into significant and insignificant coefficients. The efficiency of the method is shown for chaotic time series generated by model equations of diffusively coupled time-delay systems and for experimental chaotic time series gained from coupled electronic oscillators with time-delayed feedback.

  14. The neutron long counter NERO for studies of beta-delayed neutron emission in the r-process

    CERN Document Server

    Pereira, J; Lorusso, G; Santi, P; Couture, A; Daly, J; Del Santo, M; Elliot, T; Goerres, J; Herlitzius, C; Kratz, K -L; Lamm, L O; Lee, H Y; Montes, F; Ouellette, M; Pellegrini, E; Reeder, P; Schatz, H; Schertz, F; Schnorrenberger, L; Smith, K; Stech, E; Strandberg, E; Ugalde, C; Wiescher, M; Woehr, A; 10.1016/j.nima.2010.02.262

    2010-01-01

    The neutron long counter NERO was built at the National Superconducting Cyclotron Laboratory (NSCL), Michigan State University, for measuring beta-delayed neutron-emission probabilities. The detector was designed to work in conjunction with a beta-decay implantation station, so that beta decays and beta-delayed neutrons emitted from implanted nuclei can be measured simultaneously. The high efficiency of about 40%, for the range of energies of interest, along with the small background, are crucial for measuring beta-delayed neutron emission branchings for neutron-rich r-process nuclei produced as low intensity fragmentation beams in in-flight separator facilities.

  15. Improving Delay-Margin of Noncollocated Vibration Control of Piezo-Actuated Flexible Beams via a Fractional-Order Controller

    Directory of Open Access Journals (Sweden)

    Teerawat Sangpet

    2014-01-01

    Full Text Available Noncollocated control of flexible structures results in nonminimum-phase systems because the separation between the actuator and the sensor creates an input-output delay. The delay can deteriorate stability of closed-loop systems. This paper presents a simple approach to improve the delay-margin of the noncollocated vibration control of piezo-actuated flexible beams using a fractional-order controller. Results of real life experiments illustrate efficiency of the controller and show that the fractional-order controller has better stability robustness than the integer-order controller.

  16. Fokker-Planck approach to stochastic delay differential equations

    Science.gov (United States)

    Guillouzic, Steve

    2001-10-01

    Models written in terms of stochastic delay differential equations (SDDE's) have recently appeared in a number of fields, such as physiology, optics, and climatology. Unfortunately, the development of a Fokker-Planck approach for these equations is being hampered by their non-Markovian nature. In this thesis, an exact Fokker- Planck equation (FPE) is formulated for univariate SDDE's involving Gaussian white noise. Although this FPE is not self-sufficient, it is found to be helpful in at least two different contexts: with a short delay approximation and under an appropriate separation of time scales. In the short delay approximation, a Taylor expansion is applied to an SDDE with nondelayed diffusion and yields a nondelayed stochastic differential equation. The aforementioned FPE then allows the derivation of an alternate and complementary approximation of the original SDDE. This method is illustrated with linear and logistic SDDE's. Under the separation of time scales assumption, the FPE of a bistable system is reduced to a form that is uniquely determined by the steady-state probability density when the diffusion term of the SDDE is nondelayed. In the context of an overdamped particle with delayed coupling to a symmetrical and stochastically driven potential, the resulting FPE is used with standard techniques to express the transition rate between wells in terms of the noise amplitude and of the steady-state probability density. The same is also accomplished for the mean first passage time from one point to another. This whole approach is then applied to the case of a quartic potential, for which all realisations eventually stabilise on an oscillatory trajectory with an ever increasing amplitude. Although this latter phenomenon prevents the existence of a steady-state limit, a pseudo- steady-state probability density can be defined and used instead of the non-existent steady-state one when the transition rate to these unbounded oscillatory trajectories is

  17. Mathematical model describing the thyroids-pituitary axis with distributed time delays in hormone transportation

    Science.gov (United States)

    Neamţu, Mihaela; Stoian, Dana; Navolan, Dan Bogdan

    2014-12-01

    In the present paper we provide a mathematical model that describe the hypothalamus-pituitary-thyroid axis in autoimmune (Hashimoto's) thyroiditis. Since there is a spatial separation between thyroid and pituitary gland in the body, time is needed for transportation of thyrotropin and thyroxine between the glands. Thus, the distributed time delays are considered as both weak and Dirac kernels. The delayed model is analyzed regarding the stability and bifurcation behavior. The last part contains some numerical simulations to illustrate the effectiveness of our results and conclusions.

  18. Interferometric time delay correction for Fourier transform spectroscopy in the extreme ultraviolet

    Science.gov (United States)

    Meng, Yijian; Zhang, Chunmei; Marceau, Claude; Naumov, A. Yu.; Corkum, P. B.; Villeneuve, D. M.

    2016-09-01

    We demonstrate a Fourier transform spectrometer in the extreme ultraviolet (XUV) spectrum using a high-harmonic source, with wavelengths as short as 32 nm. The femtosecond infrared laser source is divided into two separate foci in the same gas jet to create two synchronized XUV sources. An interferometric method to determine the relative delay between the two sources is shown to improve the accuracy of the delay time, with corrections of up to 200 asec required. By correcting the time base before the Fourier transform, the frequency resolution is improved by up to an order of magnitude.

  19. Symbolic Time Separation of Events

    DEFF Research Database (Denmark)

    Amon, Tod; Hulgaard, Henrik

    1999-01-01

    We extend the TSE~\\cite{Hulgaard95} timing analysis algorithm into the symbolic domain, that is, we allow symbolic variables to be used to specify unknown parameters of the model (essentially, unknown delays) and verification algorithms which are capable of identifying not just failure or success...

  20. Completion time reduction in instantly decodable network coding through decoding delay control

    KAUST Repository

    Douik, Ahmed S.

    2014-12-01

    For several years, the completion time and the decoding delay problems in Instantly Decodable Network Coding (IDNC) were considered separately and were thought to completely act against each other. Recently, some works aimed to balance the effects of these two important IDNC metrics but none of them studied a further optimization of one by controlling the other. In this paper, we study the effect of controlling the decoding delay to reduce the completion time below its currently best known solution. We first derive the decoding-delay-dependent expressions of the users\\' and their overall completion times. Although using such expressions to find the optimal overall completion time is NP-hard, we use a heuristic that minimizes the probability of increasing the maximum of these decoding-delay-dependent completion time expressions after each transmission through a layered control of their decoding delays. Simulation results show that this new algorithm achieves both a lower mean completion time and mean decoding delay compared to the best known heuristic for completion time reduction. The gap in performance becomes significant for harsh erasure scenarios.

  1. Increased effort requirements and risk sensitivity: a comparison of delay and magnitude manipulations.

    Science.gov (United States)

    Kirshenbaum, Ari P.; Szalda-Petree, Allen D.; Haddad, Nabil F.

    2003-03-31

    Reward magnitude and delay to reward were independently manipulated in two separate experiments examining risk-sensitive choice in rats. A dual-running wheel apparatus was used and the tangential force resistance required to displace both wheels was low (50g) for half of the subjects, and high (120g) for the remaining subjects. Concurrent FI30-s and FI60-s schedules delivered equivalent amounts of food reward per unit time (i.e. 5 and 10 pellets of food, respectively), and these conditions served as the baseline treatment for all subjects. Variability, either in reward magnitude or delay, was introduced on the long-delay (60s) schedule during the second phase. All subjects were returned to the baseline condition in the third phase, and variability was introduced on the short-delay (30s) interval schedule during phase four. The subjects were again returned to the baseline condition in the fifth and final phase, ultimately yielding a five-phase ABACA design. Original baseline performance was characterized by a slight short-delay interval preference, and this pattern of performance was recovered with each subsequent presentation of the baseline condition. Overall, the data obtained from the reward magnitude and delay-to-reward manipulations were indistinguishable; subjects experiencing low-response effort requirement behaved in a risk-indifferent manner and subjects experiencing high-response effort requirement preferred the variable schedule. Implications for the daily energy budget rule on risk-sensitive foraging are discussed in light of these findings.

  2. Effect of unsignaled delays between stimuli in a chain schedule on responding and resistance to change.

    Science.gov (United States)

    Bell, Matthew C; Gomez, Belen E

    2008-03-01

    Behavioral momentum theory is an evolving theoretical account of the strength of behavior. One challenge for the theory is determining the role of signal stimuli in determining response strength. This study evaluated the effect of an unsignaled delay between the initial link and terminal link of a two-link chain schedule on resistance to change using a multiple schedule of reinforcement. Pigeons were presented two different signaled delay to reinforcement schedules. Both schedules employed a two-link chain schedule with a variable interval 120-s initial link followed by a 5-s fixed time terminal link schedule. One of the schedules included a 5-s unsignaled delay between the initial link and the terminal link. Resistance to change was assessed with two separate disruption procedures: extinction and adding a variable time 20-s schedule of reinforcement to the inter-component interval. Baseline responding was lower in the schedule with the unsignaled delay but resistance to change for the initial link was unaffected by the unsignaled delay. The results suggest that not all unsignaled delays are equal in their effect on resistance to change.

  3. Endotoxin contamination delays the foreign body reaction

    NARCIS (Netherlands)

    van Putten, Sander M.; Wubben, Maike; Plantinga, Josee A.; Hennink, Wim E.; van Luyn, Marja J. A.; Harmsen, Martin C.

    2011-01-01

    Biomaterials are at continuous risk of bacterial contamination during production and application. In vivo, bacterial contamination of biomaterials delays the foreign body reaction (FBR). Endotoxins such as lipopolysaccharides (LPS), major constituents of the bacterial cell wall, are potent stimulato

  4. Anharmonic resonances with recursive delay feedback

    Energy Technology Data Exchange (ETDEWEB)

    Goldobin, Denis S., E-mail: Denis.Goldobin@gmail.com [Department of Mathematics, University of Leicester, Leicester LE1 7RH (United Kingdom); Institute of Continuous Media Mechanics, UB RAS, Perm 614013 (Russian Federation)

    2011-09-12

    We consider application of time-delayed feedback with infinite recursion for control of anharmonic (nonlinear) oscillators subject to noise. In contrast to the case of a single delay feedback, recursive delay feedback exhibits resonances between feedback and nonlinear harmonics, leading to a resonantly strong or weak oscillation coherence even for a small anharmonicity. Remarkably, these small-anharmonicity induced resonances can be stronger than the harmonic ones. Analytical results are confirmed numerically for van der Pol and van der Pol-Duffing oscillators. -- Highlights: → We construct general theory of noisy limit-cycle oscillators with linear feedback. → We focus on coherence and 'reliability' of oscillators. → For recursive delay feedback control the theory shows importance of anharmonicity. → Anharmonic resonances are studied both numerically and analytically.

  5. How Can Atherosclerosis Be Prevented or Delayed?

    Science.gov (United States)

    ... page from the NHLBI on Twitter. How Can Atherosclerosis Be Prevented or Delayed? Taking action to control ... Rate This Content: NEXT >> Featured Video What is atherosclerosis? 05/22/2014 Describes how the build-up ...

  6. Continuous retrieval of delayed Raman polaritons

    CERN Document Server

    Smartsev, Slava; Davidson, Nir; Firstenberg, Ofer

    2016-01-01

    We use a Raman four-wave mixing process to read out light from an atomic coherence which is continuously written. This realizes a continuous source of polaritons having been delayed or effectively stored for a finite duration. Contrary to slow-light delay, which depends on the atom number and population distribution, here the effective storage duration is determined solely by intensive properties of the system, approaching the ground-state natural lifetime at the weak driving limit. The generated polaritons are background free. We experimentally probe these properties utilizing spatial atomic diffusion as an 'internal clock' for the write-read delay. A continuous source of delayed polaritons can replace discrete write-read procedures when the atomic evolution is the subject of interest, for example, when dipolar interactions lead to retrieval of non-classical light.

  7. Phase synchronization in time-delay systems.

    Science.gov (United States)

    Senthilkumar, D V; Lakshmanan, M; Kurths, J

    2006-09-01

    Though the notion of phase synchronization has been well studied in chaotic dynamical systems without delay, it has not been realized yet in chaotic time-delay systems exhibiting non-phase-coherent hyperchaotic attractors. In this paper we report identification of phase synchronization in coupled time-delay systems exhibiting hyperchaotic attractor. We show that there is a transition from nonsynchronized behavior to phase and then to generalized synchronization as a function of coupling strength. These transitions are characterized by recurrence quantification analysis, by phase differences based on a transformation of the attractors, and also by the changes in the Lyapunov exponents. We have found these transitions in coupled piecewise linear and in Mackey-Glass time-delay systems.

  8. Does Bilingualism Delay the Development of Dementia?

    Directory of Open Access Journals (Sweden)

    Amy L Atkinson

    2016-08-01

    Full Text Available It has been suggested that bilingualism (where individuals speak two languages may delay the development of dementia. However, much of the research is inconclusive. Some researchers have reported that bilingualism delays the onset and diagnosis of dementia, whilst other studies have found weak or even detrimental effects. This paper reviews a series of nine empirical studies, published up until March 2016, which investigated whether bilingualism significantly delays the onset of dementia. The article also explores whether the inconsistent findings can be attributed to differences in study designs or the definitions of bilingualism used between studies. Based on current evidence, it appears that lifelong bilingualism, where individuals frequently use both languages, may be protective against dementia. However, becoming bilingual in adulthood or using the second language infrequently is unlikely to substantially delay onset of the disease.

  9. Time to implement delayed cord clamping.

    Science.gov (United States)

    McAdams, Ryan M

    2014-03-01

    Immediate umbilical cord clamping after delivery is routine in the United States despite little evidence to support this practice. Numerous trials in both term and preterm neonates have demonstrated the safety and benefit of delayed cord clamping. In premature neonates, delayed cord clamping has been shown to stabilize transitional circulation, lessening needs for inotropic medications and reducing blood transfusions, necrotizing enterocolitis, and intraventricular hemorrhage. In term neonates, delayed cord clamping has been associated with decreased iron-deficient anemia and increased iron stores with potential valuable effects that extend beyond the newborn period, including improvements in long-term neurodevelopment. The failure to more broadly implement delayed cord clamping in neonates ignores published benefits of increased placental blood transfusion at birth and may represent an unnecessary harm for vulnerable neonates.

  10. Framework to Delay Corn Rootworm Resistance

    Science.gov (United States)

    This proposed framework is intended to delay the corn rootworm pest becoming resistant to corn genetically engineered to produce Bt proteins, which kill corn rootworms but do not affect people or wildlife. It includes requirements on Bt corn manufacturers.

  11. Uranium Determination by Delayed Neutron Counting

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Uranium is a very important resource in nuclear industry, especially in the exploiture of nuclear energy. Determination of uranium using delayed neutron counting (DNC) is simple, non-destructive, and

  12. Lauch of CERN particle accelerator delayed

    CERN Multimedia

    2007-01-01

    "Scientists seeking to uncover the secrets of the universe will have to wait a little longer after the CERN laboratory inSwitzerland yesterday confirmed a delay in tests of its massive new particle accelerator." (1 page)

  13. Performance Evaluation of Blind Tropospheric Delay correction ...

    African Journals Online (AJOL)

    Performance Evaluation of Blind Tropospheric Delay correction Models over Africa. ... consisting of surface meteorological models and global empirical models. ... GPT2w and UNB3M models with accurate International GNSS Service (IGS)- ...

  14. Internet end-to-end delay dynamics

    Institute of Scientific and Technical Information of China (English)

    Zhu Changhua; Pei Changxing; Li Jiandong; Chen Nan; Yi Yunhui

    2006-01-01

    End-to-end delay is one of the most important characteristics of Internet end-to-end packet dynamics, which can be applied to quality of services (QoS) management, service level agreement (SLA) management, congestion control algorithm development, etc. Nonstationarity and nonlinearity are found by the analysis of various delay series measured from different links. The fact that different types of links have different degree of Self-Similarity is also obtained. By constructing appropriate network architecture and neural functions, functional networks can be used to model the Internet end-to-end nonlinear delay time series. Furthermore, by using adaptive parameter studying algorithm, the nonstationarity can also be well modeled. The numerical results show that the provided functional network architecture and adaptive algorithm can precisely characterize the Internet end-to-end delay dynamics.

  15. The SAS-3 delayed command system

    Science.gov (United States)

    Hoffman, E. J.

    1975-01-01

    To meet the requirements arising from the increased complexity of the power, attitude control and telemetry systems, a full redundant high-performance control section with delayed command capability was designed for the Small Astronomy Satellite-3 (SAS-3). The relay command system of SAS-3 is characterized by 56 bystate relay commands, with capability for handling up to 64 commands in future versions. The 'short' data command service of SAS-1 and SAS-2 consisting of shifting 24-bit words to two users was expanded to five users and augmented with a 'long load' data command service (up to 4080 bits) used to program the telemetry system and the delayed command subsystem. The inclusion of a delayed command service ensures a program of up to 30 relay or short data commands to be loaded for execution at designated times. The design and system operation of the SAS-3 command section are analyzed, with special attention given to the delayed command subsystem.

  16. Monolithic Time Delay Integrated APD Arrays Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall goal of the proposed program by Epitaxial Technologies is to develop monolithic time delay integrated avalanche photodiode (APD) arrays with sensitivity...

  17. The Economic Promise of Delayed Aging.

    Science.gov (United States)

    Goldman, Dana

    2015-12-18

    Biomedicine has made enormous progress in the last half century in treating common diseases. However, we are becoming victims of our own success. Causes of death strongly associated with biological aging, such as heart disease, cancer, Alzheimer's disease, and stroke-cluster within individuals as they grow older. These conditions increase frailty and limit the benefits of continued, disease-specific improvements. Here, we show that a "delayed-aging" scenario, modeled on the biological benefits observed in the most promising animal models, could solve this problem of competing risks. The economic value of delayed aging is estimated to be $7.1 trillion over 50 years. Total government costs, including Social Security, rise substantially with delayed aging--mainly caused by longevity increases--but we show that these can be offset by modest policy changes. Expanded biomedical research to delay aging appears to be a highly efficient way to forestall disease and extend healthy life.

  18. Improved control of delayed measured systems

    Science.gov (United States)

    Claussen, Jens Christian; Schuster, Heinz Georg

    2004-11-01

    In this paper, we address the question of how the control of delayed measured chaotic systems can be improved. Both unmodified Ott-Grebogi-Yorke control and difference control can be successfully applied only for a certain range of Lyapunov numbers depending on the delay time. We show that this limitation can be overcome by at least two classes of methods, namely, by rhythmic control and by the memory methods of linear predictive logging control and memory difference control.

  19. Improvement of Delayed Neutron Counting System

    Institute of Scientific and Technical Information of China (English)

    YUAN; Guo-jun; XIAO; Cai-jin; YANG; Wei; ZHANG; Gui-ying; JIN; Xiang-chun; WANG; Ping-sheng; NI; Bang-fa

    2012-01-01

    <正>A new delayed neutron counting system, which is good at qualitative and quantitative analysis of fissionable nuclide mixture, will be established at China Advanced Research Reactor (CARR). We use 3 He proportional counters to count the delayed neutrons after the samples irradiated by reactor neutrons, including U3O8-stantard, uranium ore and enriched uranium. Then, the counting efficiency and limit of this system were calculated.

  20. Parental separation and pediatric cancer

    DEFF Research Database (Denmark)

    Grant, Sally; Carlsen, Kathrine; Bidstrup, Pernille Envold Hansen

    2012-01-01

    The purpose of this study was to determine the risk for separation (ending cohabitation) of the parents of a child with a diagnosis of cancer.......The purpose of this study was to determine the risk for separation (ending cohabitation) of the parents of a child with a diagnosis of cancer....

  1. Fast Monaural Separation of Speech

    DEFF Research Database (Denmark)

    Pontoppidan, Niels Henrik; Dyrholm, Mads

    2003-01-01

    a Factorial Hidden Markov Model, with non-stationary assumptions on the source autocorrelations modelled through the Factorial Hidden Markov Model, leads to separation in the monaural case. By extending Hansens work we find that Roweis' assumptions are necessary for monaural speech separation. Furthermore we...

  2. Metals Separation by Liquid Extraction.

    Science.gov (United States)

    Malmary, G.; And Others

    1984-01-01

    As part of a project focusing on techniques in industrial chemistry, students carry out experiments on separating copper from cobalt in chloride-containing aqueous solution by liquid extraction with triisoctylamine solvent and search the literature on the separation process of these metals. These experiments and the literature research are…

  3. Vision 2020: 2000 Separations Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Adler, Stephen [Center for Waster Reduction Technologies; Beaver, Earl [Practical Sustainability; Bryan, Paul [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Robinson, Sharon [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Watson, Jack [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2000-01-01

    This report documents the results of four workshops on the technology barriers, research needs, and priorities of the chemical, agricultural, petroleum, and pharmaceutical industries as they relate to separation technologies utilizing adsorbents, crystallization, distillation, extraction, membranes, separative reactors, ion exchange, bioseparations, and dilute solutions.

  4. Electrostatically enhanced core separator system

    Energy Technology Data Exchange (ETDEWEB)

    Easom, B.H.; Smolensky, L.A.; Altman, R.F. [LSR Technologies, Inc., Acton, MA (United States)

    1997-12-31

    The Electrostatically Enhanced Core Separator (EECS) system employs the same design principles as the mechanical Core Separator system plus an electrostatic separation enhancing technique. The EECS system contains a special type of separator, the EECS element, a conventional solids collector and means for flow recirculation. In the EECS system solids separation and collection are accomplished in two different components. The EECS element acts as a separator, not as a collector so particles are not collected on its walls. This eliminates or at least mitigates the problems associated with reentrainment (due to high or low dust resistivity), seepage (due to gas flow below the precipitator plates and over the hoppers), sneakage (due to gas flow both above and below the precipitator plates), and rapping reentrainment. If the EECS separation efficiency is high enough, particles cannot leave the system with the process stream. They recirculate until they are extracted by the collector. As a result, the separation efficiency of the EECS element determines the efficiency of the system, even if the collector efficiency is relatively low. 8 refs., 3 figs.

  5. Relational Parametricity and Separation Logic

    DEFF Research Database (Denmark)

    Birkedal, Lars; Yang, Hongseok

    2008-01-01

    Separation logic is a recent extension of Hoare logic for reasoning about programs with references to shared mutable data structures. In this paper, we provide a new interpretation of the logic for a programming language with higher types. Our interpretation is based on Reynolds's relational...... parametricity, and it provides a formal connection between separation logic and data abstraction. Udgivelsesdato: 2008...

  6. Tropospheric delay statistics measured by two site test interferometers at Goldstone, California

    Science.gov (United States)

    Morabito, David D.; D'Addario, Larry R.; Acosta, Roberto J.; Nessel, James A.

    2013-12-01

    Site test interferometers (STIs) have been deployed at two locations within the NASA Deep Space Network tracking complex in Goldstone, California. An STI measures the difference of atmospheric delay fluctuations over a distance comparable to the separations of microwave antennas that could be combined as phased arrays for communication and navigation. The purpose of the Goldstone STIs is to assess the suitability of Goldstone as an uplink array site and to statistically characterize atmosphere-induced phase delay fluctuations for application to future arrays. Each instrument consists of two ~1 m diameter antennas and associated electronics separated by ~200 m. The antennas continuously observe signals emitted by geostationary satellites and produce measurements of the phase difference between the received signals. The two locations at Goldstone are separated by 12.5 km and differ in elevation by 119 m. We find that their delay fluctuations are statistically similar but do not appear as shifted versions of each other, suggesting that the length scale for evolution of the turbulence pattern is shorter than the separation between instruments. We also find that the fluctuations are slightly weaker at the higher altitude site.

  7. Testing Orions Fairing Separation System

    Science.gov (United States)

    Martinez, Henry; Cloutier, Chris; Lemmon, Heber; Rakes, Daniel; Oldham, Joe; Schlagel, Keith

    2014-01-01

    Traditional fairing systems are designed to fully encapsulate and protect their payload from the harsh ascent environment including acoustic vibrations, aerodynamic forces and heating. The Orion fairing separation system performs this function and more by also sharing approximately half of the vehicle structural load during ascent. This load-share condition through launch and during jettison allows for a substantial increase in mass to orbit. A series of component-level development tests were completed to evaluate and characterize each component within Orion's unique fairing separation system. Two full-scale separation tests were performed to verify system-level functionality and provide verification data. This paper summarizes the fairing spring, Pyramidal Separation Mechanism and forward seal system component-level development tests, system-level separation tests, and lessons learned.

  8. Ignition Delay Studies on Hypergolic Fuel Grains

    Directory of Open Access Journals (Sweden)

    S. R. Jain

    1988-07-01

    Full Text Available The ignition delays of several solid hypergolic fuel compositions, casted using various polymeric binders, or as melts, have been determined with fuming nitric acid as oxidizer. The ignition delays of various hypergolic fuel compositions increase drasticaliy on casting with binders like. carboxyl or hydroxyl termninated polybutadiene. Fuel grains cast using some newly syhthesised epoxy  resins with other ingrcdients, such as curing agent, magnesium powder and fuel, have short ignition delays of the order of 200 ms, and also good mechanical strength. Increasing the amount of binder in the composition retards the hypergolicity of the rain. Similar studies have been made on melt-cast systems using low melting hypergolic fuels for casting fuel powders. The ignition delays of the melt-cast grains, are longer than those determined taking the composition in the powder form. The effect of highly hypergolic additives, and metal powders, on the ignition delay of the cast compositions has been determined. Grains having good mechanical strength and short ignition delays have been obtained by optimising the fuel grain composition.

  9. Operant variability when reinforcement is delayed.

    Science.gov (United States)

    Wagner, Katie; Neuringer, Allen

    2006-05-01

    Operant responses are often weakened when delays are imposed between the responses and reinforcers. We examined what happens when delayed reinforcers were contingent upon operant response variability. Three groups of rats were rewardedfor varying their response sequences, with onegroup rewarded for high variability, another for middle, and the third for low levels. Consistent with many reports in the literature, responding slowed significantly in all groups as delays were lengthened. Consistent with other reports, large differences in variability were maintained across the three groups despite the delays. Reinforced variability appears to be relatively immune to disruption by such things as delays, response slowing, prefeeding, and noncontingent reinforcement. Furthermore, the small effects on variability depended on baseline levels: As delays lengthened, variability increased in the low group, was statistically unchanged in the middle group, and decreased in the high group, an interaction similar to that reported previously when reinforcement frequencies were lowered. Thus, variable operant responding is controlled by reinforcement contingencies, but sometimes differently than more commonly studied repetitive responding.

  10. Beyond Linear Delay Multipliers in Air Transport

    Directory of Open Access Journals (Sweden)

    Seddik Belkoura

    2017-01-01

    Full Text Available Delays are considered one of the most important burdens of air transport, both for their social and environmental consequences and for the cost they cause for airlines and passengers. It is therefore not surprising that a large effort has been devoted to study how they propagate through the system. One of the most important indicators to assess such propagation is the delay multiplier, a ratio between outbound and inbound average delays; in spite of its widespread utilisation, its simplicity precludes capturing all details about the dynamics behind the diffusion process. Here we present a methodology that extracts a more complete relationship between the in- and outbound delays, distinguishing a linear and a nonlinear phase and thus yielding a richer description of the system’s response as a function of the delay magnitude. We validate the methodology through the study of a historical data set of flights crossing the European airspace and show how its most important airports have heterogeneous ways of reacting to extreme delays and that this reaction strongly depends on some of their global properties.

  11. The reasons for delay lumbar puncture

    Directory of Open Access Journals (Sweden)

    MH. Lotfi

    2017-04-01

    Full Text Available Early diagnosis of meningitis and encephalitis and prompt initiation of appropriate therapy is vital and any delay will lead to high mortality and serious and permanent morbidity. The main purpose of this study was to evaluate the management of 220 patients with suspected central nervous system (CNS infections (meningitis and encephalitis to determine the percentage of patients’ suspected CNS infection undergo lumbar puncture in acceptable time (in accordance with conventional algorithms. In this descriptive study, patients with suspected CNS infections admitted to Bu-Ali and Qods hospitals, in the period July 2013 to December 2015 were studied. Information of 220 patients was collected. Continuous variables were summarized as means ± standard deviation and categorical variables as frequencies and percentages. Lumbar puncture (LP in patients was delayed in 200 cases (91%. Most common causes of delay in performing LP were prolongation of the process of determining patient needs to puncture, satisfying patients, CT scan delay and the delay in allowing LP by neurologist. In this study, delaying LP rate was higher than other studies. It seems certain pattern in assistants’ visits for counseling. CT requests and neurologic consultation before LP performed for all adult patients.

  12. Locomotive Assignment Optimization Including Train Delays

    Directory of Open Access Journals (Sweden)

    Sandra Kasalica

    2013-10-01

    Full Text Available Intention– Cyclic locomotive assignment planning is a specific type of organization of locomotive usage, and in fact, it means putting the complete workload to a closed chain, which is repeated periodically. The concept of cyclic locomotive assignment planning type organization in the area of train traction has proven in practice as the best one, but as it is made for in-advance defined timetable and without considering the stochastic nature of the timetable realization process, it leads to incompatibility in using locomotives. Methodology – Methodology defined in this paper contains: research of train delays on the Serbian Railways and Montenegrin Railways networks, analysis of the real system organization of locomotive usage in conditions of train delays, theoretical thesis of solving the problem of optimal cyclic locomotive assignment planning in conditions of train delays, designing of a model with algorithms, preparing the software package, testing the model and program with results, as well as the conclusions drawn from the complete research project. Results– The optimization model of cyclic locomotive assignment planning during the process of making timetable including train delays has been defined. Conclusion –The obtained results have shown as expected, that the larger delays of trains required a larger number of locomotives. However, by using this model it is possible to optimize the required number of locomotives, taking into account the real time delays of trains.

  13. Optimal Control with Time Delays via the Penalty Method

    Directory of Open Access Journals (Sweden)

    Mohammed Benharrat

    2014-01-01

    Full Text Available We prove necessary optimality conditions of Euler-Lagrange type for a problem of the calculus of variations with time delays, where the delay in the unknown function is different from the delay in its derivative. Then, a more general optimal control problem with time delays is considered. Main result gives a convergence theorem, allowing us to obtain a solution to the delayed optimal control problem by considering a sequence of delayed problems of the calculus of variations.

  14. Similar Impacts of the Interaural Delay and Interaural Correlation on Binaural Gap Detection.

    Science.gov (United States)

    Kong, Lingzhi; Xie, Zilong; Lu, Lingxi; Qu, Tianshu; Wu, Xihong; Yan, Jun; Li, Liang

    2015-01-01

    The subjective representation of the sounds delivered to the two ears of a human listener is closely associated with the interaural delay and correlation of these two-ear sounds. When the two-ear sounds, e.g., arbitrary noises, arrive simultaneously, the single auditory image of the binaurally identical noises becomes increasingly diffuse, and eventually separates into two auditory images as the interaural correlation decreases. When the interaural delay increases from zero to several milliseconds, the auditory image of the binaurally identical noises also changes from a single image to two distinct images. However, measuring the effect of these two factors on an identical group of participants has not been investigated. This study examined the impacts of interaural correlation and delay on detecting a binaurally uncorrelated fragment (interaural correlation = 0) embedded in the binaurally correlated noises (i.e., binaural gap or break in interaural correlation). We found that the minimum duration of the binaural gap for its detection (i.e., duration threshold) increased exponentially as the interaural delay between the binaurally identical noises increased linearly from 0 to 8 ms. When no interaural delay was introduced, the duration threshold also increased exponentially as the interaural correlation of the binaurally correlated noises decreased linearly from 1 to 0.4. A linear relationship between the effect of interaural delay and that of interaural correlation was described for listeners participating in this study: a 1 ms increase in interaural delay appeared to correspond to a 0.07 decrease in interaural correlation specific to raising the duration threshold. Our results imply that a tradeoff may exist between the impacts of interaural correlation and interaural delay on the subjective representation of sounds delivered to two human ears.

  15. Similar Impacts of the Interaural Delay and Interaural Correlation on Binaural Gap Detection.

    Directory of Open Access Journals (Sweden)

    Lingzhi Kong

    Full Text Available The subjective representation of the sounds delivered to the two ears of a human listener is closely associated with the interaural delay and correlation of these two-ear sounds. When the two-ear sounds, e.g., arbitrary noises, arrive simultaneously, the single auditory image of the binaurally identical noises becomes increasingly diffuse, and eventually separates into two auditory images as the interaural correlation decreases. When the interaural delay increases from zero to several milliseconds, the auditory image of the binaurally identical noises also changes from a single image to two distinct images. However, measuring the effect of these two factors on an identical group of participants has not been investigated. This study examined the impacts of interaural correlation and delay on detecting a binaurally uncorrelated fragment (interaural correlation = 0 embedded in the binaurally correlated noises (i.e., binaural gap or break in interaural correlation. We found that the minimum duration of the binaural gap for its detection (i.e., duration threshold increased exponentially as the interaural delay between the binaurally identical noises increased linearly from 0 to 8 ms. When no interaural delay was introduced, the duration threshold also increased exponentially as the interaural correlation of the binaurally correlated noises decreased linearly from 1 to 0.4. A linear relationship between the effect of interaural delay and that of interaural correlation was described for listeners participating in this study: a 1 ms increase in interaural delay appeared to correspond to a 0.07 decrease in interaural correlation specific to raising the duration threshold. Our results imply that a tradeoff may exist between the impacts of interaural correlation and interaural delay on the subjective representation of sounds delivered to two human ears.

  16. Delay-dependent H-infinity control for continuous time-delay systems via state feedback

    Institute of Scientific and Technical Information of China (English)

    Xinchun JIA; Yibo GAO; Jingmei ZHANG; Nanning ZHENG

    2007-01-01

    The delay-dependent H-infinity analysis and H-infinity control problems for continuous time-delay systems are studied. By introducing an equality with some free weighting matrices, an improved criterion of delay-dependent stability with H-infinity performance for such systems is presented, and a criterion of existence and some design methods of delay-dependent H-infinity controller for such systems are proposed in term of a set of matrix inequalities, which is solved efficiently by an iterative algorithm. Further, the corresponding results for the delay-dependent robust H-infinity analysis and robust H-infinity control problems for continuous time-delay uncertain systems are given. Finally, two numerical examples are given to illustrate the efficiency of the proposed method by comparing with the other existing results.

  17. Delayed antibiotic prescriptions for respiratory infections.

    Science.gov (United States)

    Spurling, Geoffrey Kp; Del Mar, Chris B; Dooley, Liz; Foxlee, Ruth; Farley, Rebecca

    2017-09-07

    Concerns exist regarding antibiotic prescribing for respiratory tract infections (RTIs) owing to adverse reactions, cost, and antibacterial resistance. One proposed strategy to reduce antibiotic prescribing is to provide prescriptions, but to advise delay in antibiotic use with the expectation that symptoms will resolve first. This is an update of a Cochrane Review originally published in 2007, and updated in 2010 and 2013. To evaluate the effects on clinical outcomes, antibiotic use, antibiotic resistance, and patient satisfaction of advising a delayed prescription of antibiotics in respiratory tract infections. For this 2017 update we searched the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, Issue 4, 2017), which includes the Cochrane Acute Respiratory Infection Group's Specialised Register; Ovid MEDLINE (2013 to 25 May 2017); Ovid Embase (2013 to 2017 Week 21); EBSCO CINAHL Plus (1984 to 25 May 2017); Web of Science (2013 to 25 May 2017); WHO International Clinical Trials Registry Platform (1 September 2017); and ClinicalTrials.gov (1 September 2017). Randomised controlled trials involving participants of all ages defined as having an RTI, where delayed antibiotics were compared to immediate antibiotics or no antibiotics. We defined a delayed antibiotic as advice to delay the filling of an antibiotic prescription by at least 48 hours. We considered all RTIs regardless of whether antibiotics were recommended or not. We used standard Cochrane methodological procedures. Three review authors independently extracted and collated data. We assessed the risk of bias of all included trials. We contacted trial authors to obtain missing information. For this 2017 update we added one new trial involving 405 participants with uncomplicated acute respiratory infection. Overall, this review included 11 studies with a total of 3555 participants. These 11 studies involved acute respiratory infections including acute otitis media (three studies

  18. Interconnected delay and state observer for nonlinear systems with time-varying input delay

    OpenAIRE

    Léchappé, V; Moulay, Emmanuel; Plestan, F; Glumineau, A.

    2016-01-01

    International audience; This work presents a general framework to estimate both state and delay thanks to two interconnected observers. This scheme can be applied to a large class of nonlinear systems with time-varying input delay. In order to illustrate this approach, a new delay observer based on an optimization technique is proposed. Theoretical results are illustrated and compared with existing works in simulation.

  19. Delay dependent stability criteria for recurrent neural networks with time varying delays

    Institute of Scientific and Technical Information of China (English)

    Zhanshan WANG; Huaguang ZHANG

    2009-01-01

    This paper aims to present some delay-dependent global asymptotic stability criteria for recurrent neural networks with time varying delays.The obtained results have no restriction on the magnitude of derivative of time varying delay,and can be easily checked due to the form of linear matrix inequality.By comparison with some previous results,the obtained results are less conservative.A numerical example is utilized to demonstrate the effectiveness of the obtained results.

  20. Improving Delay-Range-Dependent Stability Condition for Systems with Interval Time-Varying Delay

    Directory of Open Access Journals (Sweden)

    Wei Qian

    2013-01-01

    Full Text Available This paper discusses the delay-range-dependent stability for systems with interval time-varying delay. Through defining the new Lyapunov-Krasovskii functional and estimating the derivative of the LKF by introducing new vectors, using free matrices and reciprocally convex approach, the new delay-range-dependent stability conditions are obtained. Two well-known examples are given to illustrate the less conservatism of the proposed theoretical results.

  1. Delay-dependent guaranteed cost control for uncertain systems with both state and input delays

    Institute of Scientific and Technical Information of China (English)

    Xuanfang YANG; Wuhua CHEN; Huajing FANG

    2004-01-01

    This paper considers the guaranteed cost control problem for a class of uncertain linear systems with both state and input delays.By representing the time-delay system in the descriptor system form and using a recent result on bounding of cross products of vectors,we obtain new delay-dependent sufficient conditions for the existence of the guaranteed cost controller in terms of linear matrix inequalities.Two examples are presented which show the effectiveness of our approach.

  2. Design of a Novel Current Balanced Voltage Controlled Delay Element

    Directory of Open Access Journals (Sweden)

    Pooja Saxena

    2014-04-01

    Full Text Available This paper presents a design of fast voltage controlled delay element based on modified version of low noise Current Balanced Logic (CBL. This delay element provides identical rising and falling edge delays controlled by the single control voltage. The post layout tunable delay range is from 140 ps to 800 ps over control voltage range of 0 to 2.1 V. An analysis for the delay element is also presented, which is in agreement with the simulated delays. A Delay Lock Loop (DLL is designed using this delay element to verify its performance.

  3. Apparatus and Method for Compensating for Process, Voltage, and Temperature Variation of the Time Delay of a Digital Delay Line

    Science.gov (United States)

    Seefeldt, James (Inventor); Feng, Xiaoxin (Inventor); Roper, Weston (Inventor)

    2013-01-01

    A process, voltage, and temperature (PVT) compensation circuit and a method of continuously generating a delay measure are provided. The compensation circuit includes two delay lines, each delay line providing a delay output. The two delay lines may each include a number of delay elements, which in turn may include one or more current-starved inverters. The number of delay lines may differ between the two delay lines. The delay outputs are provided to a combining circuit that determines an offset pulse based on the two delay outputs and then averages the voltage of the offset pulse to determine a delay measure. The delay measure may be one or more currents or voltages indicating an amount of PVT compensation to apply to input or output signals of an application circuit, such as a memory-bus driver, dynamic random access memory (DRAM), a synchronous DRAM, a processor or other clocked circuit.

  4. Influence of UAS Pilot Communication and Execution Delay on Controller's Acceptability Ratings of UAS-ATC Interactions

    Science.gov (United States)

    Vu, Kim-Phuong L.; Morales, Gregory; Chiappe, Dan; Strybel, Thomas Z.; Battiste, Vernol; Shively, Jay; Buker, Timothy J

    2013-01-01

    Successful integration of UAS in the NAS will require that UAS interactions with the air traffic management system be similar to interactions between manned aircraft and air traffic management. For example, UAS response times to air traffic controller (ATCo) clearances should be equivalent to those that are currently found to be acceptable with manned aircraft. Prior studies have examined communication delays with manned aircraft. Unfortunately, there is no analogous body of research for UAS. The goal of the present study was to determine how UAS pilot communication and execution delays affect ATCos' acceptability ratings of UAS pilot responses when the UAS is operating in the NAS. Eight radar-certified controllers managed traffic in a modified ZLA sector with one UAS flying in it. In separate scenarios, the UAS pilot verbal communication and execution delays were either short (1.5 s) or long (5 s) and either constant or variable. The ATCo acceptability of UAS pilot communication and execution delays were measured subjectively via post trial ratings. UAS verbal pilot communication delay, were rated as acceptable 92% of the time when the delay was short. This acceptability level decreased to 64% when the delay was long. UAS pilot execution delay had less of an influence on ATCo acceptability ratings in the present stimulation. Implications of these findings for UAS in the NAS integration are discussed.

  5. Pseudo-stationary separation materials for highly parallel separations.

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Anup K.; Palmer, Christopher (University of Montana, Missoula, MT)

    2005-05-01

    Goal of this study was to develop and characterize novel polymeric materials as pseudostationary phases in electrokinetic chromatography. Fundamental studies have characterized the chromatographic selectivity of the materials as a function of chemical structure and molecular conformation. The selectivities of the polymers has been studied extensively, resulting in a large body of fundamental knowledge regarding the performance and selectivity of polymeric pseudostationary phases. Two polymers have also been used for amino acid and peptide separations, and with laser induced fluorescence detection. The polymers performed well for the separation of derivatized amino acids, and provided some significant differences in selectivity relative to a commonly used micellar pseudostationary phase. The polymers did not perform well for peptide separations. The polymers were compatible with laser induced fluorescence detection, indicating that they should also be compatible with chip-based separations.

  6. WASTE PRINTED CIRCUIT BOARDS SEPARATION IN ELECTROSTATIC SEPARATOR

    Directory of Open Access Journals (Sweden)

    Branimir Fuk

    2012-12-01

    Full Text Available Printed circuit boards from electronic waste are very important source of precious metals by recycling. The biggest challenge is liberation and separation of useful components; thin film which contains copper, zinc, tin, lead and precious metals like silver, gold and palladium from non useful components; polymers, ceramics and glass fibbers. The paper presents results for separation of shredded printed circuit boards from TV sets in electrostatic separator. Testing where conducted with material class 2/1 and 1/0.5 mm in laboratory on equipment for mineral processing. Results showed influence from independent variable; separation knife gradient, drum rotation speed and voltage on concentrate quality and recovery (the paper is published in Croatian.

  7. Delay-dependent robust H∞ control for uncertain fuzzy hyperbolic systems with multiple delays

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The robust H∞ control problem was considered for a class of fuzzy hyperbolic model (FHM) systems with parametric uncertainties and multiple delays. First, FHM modeling method was presented for time-delay nonlinear systems. Then, by using Lyapunov-Krasovskii approaches, delay-dependent sufficient condition for the existence of a kind of state feedback controller was proposed, which was expressed as linear matrix inequalities (LMIs). The controller can guarantee that the resulting closed-loop system is robustly asymptotically stable with a prescribed H∞ performance level for all admissible uncertainties and time-delay. Finally, a simulation example was provided to illustrate the effectiveness of the proposed approach.

  8. Deriving real delay time statistics from the complex delay time statistics in weakly disordered optical media

    OpenAIRE

    Pradhan, Prabhakar; Sahay, Peeyush; Almabadi, Huda M.

    2016-01-01

    Considering the complex reflection amplitude R=|R|exp(i{\\theta}) of a light wave, real delay time {\\tau}_r (i.e., sojourn or Wigner delay time), which is the energy derivative of the real phase ({\\tau}_r =d{\\theta}/cdk), and complex delay time {\\tau}_i , which is the energy derivative of the reflection coefficient ({\\tau}_i=d{\\theta}_i/cdk, |R|=r^1/2=exp(-{\\theta}_i)), have the same statistical form and a mirror image with a shift in time in weak disorder and short length regime. Real delay t...

  9. Adaptive global synchronization of a general complex dynamical network with non-delayed and delayed coupling

    Science.gov (United States)

    Wen, Sun; Chen, Shihua; Guo, Wanli

    2008-10-01

    This Letter investigates the global synchronization of a general complex dynamical network with non-delayed and delayed coupling. Based on Lasalle's invariance principle, adaptive global synchronization criteria is obtained. Analytical result shows that under the designed adaptive controllers, a general complex dynamical network with non-delayed and delayed coupling can globally asymptotically synchronize to a given trajectory. What is more, the node dynamic need not satisfy the very strong and conservative uniformly Lipschitz condition and the coupling matrix is not assumed to be symmetric or irreducible. Finally, numerical simulations are presented to verify the effectiveness of the proposed synchronization criteria.

  10. Adaptive global synchronization of a general complex dynamical network with non-delayed and delayed coupling

    Energy Technology Data Exchange (ETDEWEB)

    Wen Sun [College of Mathematics and Statistics, Wuhan University, Wuhan 430072 (China)], E-mail: sunwen_2201@163.com; Chen Shihua; Guo Wanli [College of Mathematics and Statistics, Wuhan University, Wuhan 430072 (China)

    2008-10-13

    This Letter investigates the global synchronization of a general complex dynamical network with non-delayed and delayed coupling. Based on Lasalle's invariance principle, adaptive global synchronization criteria is obtained. Analytical result shows that under the designed adaptive controllers, a general complex dynamical network with non-delayed and delayed coupling can globally asymptotically synchronize to a given trajectory. What is more, the node dynamic need not satisfy the very strong and conservative uniformly Lipschitz condition and the coupling matrix is not assumed to be symmetric or irreducible. Finally, numerical simulations are presented to verify the effectiveness of the proposed synchronization criteria.

  11. Delayed Hopf bifurcation in time-delayed slow-fast systems

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    This paper presents an investigation on the phenomenon of delayed bifurcation in time-delayed slow-fast differential systems.Here the two delayed’s have different meanings.The delayed bifurcation means that the bifurcation does not happen immediately at the bifurcation point as the bifurcation parameter passes through some bifurcation point,but at some other point which is above the bifurcation point by an obvious distance.In a time-delayed system,the evolution of the system depends not only on the present state but also on past states.In this paper,the time-delayed slow-fast system is firstly simplified to a slow-fast system without time delay by means of the center manifold reduction,and then the so-called entry-exit function is defined to characterize the delayed bifurcation on the basis of Neishtadt’s theory.It shows that delayed Hopf bifurcation exists in time-delayed slow-fast systems,and the theoretical prediction on the exit-point is in good agreement with the numerical calculation,as illustrated in the two illustrative examples.

  12. Controlling a time-delay system using multiple delay feedback control

    Institute of Scientific and Technical Information of China (English)

    Qi Wei; Zhang Yan; Wang Ying-Hai

    2007-01-01

    In this paper multiple delay feedback control (MDFC) with different and independent delay times is shown to be an efficient method for stabilizing fixed points in finite-dimensional dynamical systems. Whether MDFC can be applied to infinite-dimensional systems has been an open question. In this paper we find that for infinite-dimensional systems modelled by delay differential equations, MDFC works well for stabilizing (unstable) steady states in long-, moderate-and short-time delay regions, in particular for the hyperchaotic case.

  13. Time-Delay Estimation using the Characteristic Roots of Delay Differential Equations

    Directory of Open Access Journals (Sweden)

    Sun Yi

    2012-01-01

    Full Text Available Problem statement: For ordinary dynamic systems (i.e., non-delayed, various methods such as linear least-squares, gradient-weighted least-squares, Kalman filtering and other robust techniques have been widely used in signal processing, robotics, civil engineering. On the other hand, time-delay estimation of systems with unknown time-delay is still a challenging problem due to difficulty in formulation caused. Approach: The presented method makes use of the Lambert W function and analytical solutions of scalar first-order Delay Differential Equations (DDEs. The Lambert W function has been known to be useful in solving delay differential equations. From the solutions in terms of the Lambert W function, the dominant characteristic roots can be obtained and used to estimate time-delays. The function is already embedded in various software packages (e.g., MATLAB and thus, the presented method can be readily used for time-delay systems. Results: The presented method and the provided examples show ease of formulation and accuracy of time-delay estimation. Conclusion: Estimation of time-delays can be conducted in an analytical way. The presented method will be extended to general systems of DDEs and application to physical systems.

  14. Multivariate Markov processes for stochastic systems with delays: application to the stochastic Gompertz model with delay.

    Science.gov (United States)

    Frank, T D

    2002-07-01

    Using the method of steps, we describe stochastic processes with delays in terms of Markov diffusion processes. Thus, multivariate Langevin equations and Fokker-Planck equations are derived for stochastic delay differential equations. Natural, periodic, and reflective boundary conditions are discussed. Both Ito and Stratonovich calculus are used. In particular, our Fokker-Planck approach recovers the generalized delay Fokker-Planck equation proposed by Guillouzic et al. The results obtained are applied to a model for population growth: the Gompertz model with delay and multiplicative white noise.

  15. Delay-dependent criteria for the robust stability of systems with time-varying delay

    Institute of Scientific and Technical Information of China (English)

    Min WU; Yong HE; Jinhua SHE

    2003-01-01

    The problem of delay-dependent robust stability for systems with titne-varying delay has been considered. By using the S-procedure and the Park' s inequality in the recent issue, a delay-dependent robust stability criterion which is less conservative than the previous results has been derived for time-delay systems with time-varying structured uncertainties. The same idea has also been easily extended to the systems with nonlinear perturbations. Numerical examples illustrated the effectiveness and the improvement of the proposed approach.

  16. Delayed feedback control of time-delayed chaotic systems: Analytical approach at Hopf bifurcation

    Energy Technology Data Exchange (ETDEWEB)

    Vasegh, Nastaran [Faculty of Electrical Engineering, K.N. Toosi University of Technology, PO Box 16315-1355, Tehran (Iran, Islamic Republic of)], E-mail: vasegh@eetd.kntu.ac.ir; Sedigh, Ali Khaki [Faculty of Electrical Engineering, K.N. Toosi University of Technology, PO Box 16315-1355, Tehran (Iran, Islamic Republic of)

    2008-07-28

    This Letter is concerned with bifurcation and chaos control in scalar delayed differential equations with delay parameter {tau}. By linear stability analysis, the conditions under which a sequence of Hopf bifurcation occurs at the equilibrium points are obtained. The delayed feedback controller is used to stabilize unstable periodic orbits. To find the controller delay, it is chosen such that the Hopf bifurcation remains unchanged. Also, the controller feedback gain is determined such that the corresponding unstable periodic orbit becomes stable. Numerical simulations are used to verify the analytical results.

  17. Hydrogen isotope separation; Separation isotopique de l'hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    Leterq, D.; Guidon, H. [CEA Bruyeres-le-Chatel, 91 (France)

    2001-12-01

    CEA-DAM has been operating for more than 20 years hydrogen isotopes separation by batch chromatography with palladium coated on alumina as absorbing material. The efforts have been focused on the development of two new separation processes: TCAP (Thermal Cycling Absorption Process) and chromatography an molecular sieve at 77 K. H{sub 2}/D{sub 2} first tests results are promising. (authors)

  18. Particle separations by electrophoretic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Ballou, N.E.; Petersen, S.L.; Ducatte, G.R.; Remcho, V.T.

    1996-03-01

    A new method for particle separations based on capillary electrophoresis has been developed and characterized. It uniquely separates particles according to their chemical nature. Separations have been demonstrated with chemically modified latex particles and with inorganic oxide and silicate particles. Separations have been shown both experimentally and theoretically to be essentially independent of particle size in the range of about 0.2 {mu}m to 10 {mu}m. The method has been applied to separations of U0{sub 2} particles from environmental particulate material. For this, an integrated method was developed for capillary electrophoretic separation, collection of separated fractions, and determinations of U0{sub 2} and environmental particles in each fraction. Experimental runs with the integrated method on mixtures of UO{sub 2} particles and environmental particulate material demonstrated enrichment factors of 20 for UO{sub 2} particles in respect to environmental particles in the U0{sub 2}containing fractions. This enrichment factor reduces the costs and time for processing particulate samples by the lexan process by a factor of about 20.

  19. Coherence versus reliability of stochastic oscillators with delayed feedback.

    Science.gov (United States)

    Goldobin, Denis S

    2008-12-01

    For noisy self-sustained oscillators, both reliability, the stability of a response to a noisy driving, and coherence, understood in the sense of constancy of oscillation frequency, are important characteristics. Although both characteristics and techniques for controlling them have received great attention from researchers, owing to their importance for neurons, lasers, clocks, electric generators, etc., these characteristics were previously considered separately. In this paper, a strong quantitative relation between coherence and reliability is revealed for a limit cycle oscillator subject to a weak noisy driving and a linear delayed feedback, a convection control tool. The analytical findings are verified and enriched with a numerical simulation for the Van der Pol-Duffing oscillator.

  20. β -delayed fission and α decay of 196At

    Science.gov (United States)

    Truesdale, V. L.; Andreyev, A. N.; Ghys, L.; Huyse, M.; Van Duppen, P.; Sels, S.; Andel, B.; Antalic, S.; Barzakh, A.; Capponi, L.; Cocolios, T. E.; Derkx, X.; De Witte, H.; Elseviers, J.; Fedorov, D. V.; Fedosseev, V. N.; Heßberger, F. P.; Kalaninová, Z.; Köster, U.; Lane, J. F. W.; Liberati, V.; Lynch, K. M.; Marsh, B. A.; Mitsuoka, S.; Nagame, Y.; Nishio, K.; Ota, S.; Pauwels, D.; Popescu, L.; Radulov, D.; Rapisarda, E.; Rothe, S.; Sandhu, K.; Seliverstov, M. D.; Sjödin, A. M.; Van Beveren, C.; Van den Bergh, P.; Wakabayashi, Y.

    2016-09-01

    A nuclear-decay spectroscopy study of the neutron-deficient isotope 196At is reported where an isotopically pure beam was produced using the selective Resonance Ionization Laser Ion Source and On-Line Isotope Mass Separator (CERN). The fine-structure α decay of 196At allowed the low-energy excited states in the daughter nucleus 192Bi to be investigated. A β -delayed fission study of 196At was also performed. A mixture of symmetric and asymmetric fission-fragment mass distributions of the daughter isotope 196Po (populated by β decay of 196At) was deduced based on the measured fission-fragment energies. A β DF probability Pβ DF(196At) =9 (1 ) ×10-5 was determined.

  1. Impulsive control of time-delay systems using delayed impulse and its application to impulsive master-slave synchronization

    Energy Technology Data Exchange (ETDEWEB)

    Sun Jitao [Department of Mathematics, Tongji University, Shanghai 200092 (China); Centre for Intelligent and Networked Systems, Central Queensland University, Rockhampton Qld 4702 (Australia); Han Qinglong [Centre for Intelligent and Networked Systems, Central Queensland University, Rockhampton Qld 4702 (Australia); School of Computing Sciences, Central Queensland University, Rockhampton Qld 4702 (Australia)], E-mail: q.han@cqu.edu.au; Jiang Xiefu [Centre for Intelligent and Networked Systems, Central Queensland University, Rockhampton Qld 4702 (Australia); School of Automation, Hangzhou Dianzi University, Hangzhou 310018, Zhejiang (China)

    2008-10-13

    This Letter is concerned with impulsive control of a class of nonlinear time-delay systems. Some uniform stability criteria for the closed-loop time-delay system under delayed impulsive control are derived by using piecewise Lyapunov functions. Then the criteria are applied to impulsive master-slave synchronization of some secure communication systems with transmission delays and sample delays under delayed impulsive control. Two numerical examples are given to illustrate the effectiveness of the derived results.

  2. System identification and trajectory optimization for guided store separation

    Science.gov (United States)

    Carter, Ryan E.

    Combat aircraft utilize expendable stores such as missiles, bombs, flares, and external tanks to execute their missions. Safe and acceptable separation of these stores from the parent aircraft is essential for meeting the mission objectives. In many cases, the employed missile or bomb includes an onboard guidance and control system to enable precise engagement of the selected target. Due to potential interference, the guidance and control system is usually not activated until the store is sufficiently far away from the aircraft. This delay may result in large perturbations from the desired flight attitude caused by separation transients, significantly reducing the effectiveness of the store and jeopardizing mission objectives. The purpose of this research is to investigate the use of a transitional control system to guide the store during separation. The transitional control system, or "store separation autopilot", explicitly accounts for the nonuniform flow field through characterization of the spatially variant aerodynamics of the store during separation. This approach can be used to mitigate aircraft-store interference and leverage aerodynamic interaction to improve separation characteristics. This investigation proceeds in three phases. First, system identification is used to determine a parametric model for the spatially variant aerodynamics. Second, the store separation problem is recast into a trajectory optimization problem, and optimal control theory is used to establish a framework for designing a suitable reference trajectory with explicit dependence on the spatially variant aerodynamics. Third, neighboring optimal control is used to construct a linear-optimal feedback controller for correcting deviations from the nominal reference trajectory due varying initial conditions, modeling errors, and flowfield perturbations. An extended case study based on actual wind tunnel and flight test measurements is used throughout to illustrate the effectiveness of the

  3. Efficient separations & processing crosscutting program

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    The Efficient Separations and Processing Crosscutting Program (ESP) was created in 1991 to identify, develop, and perfect chemical and physical separations technologies and chemical processes which treat wastes and address environmental problems throughout the DOE complex. The ESP funds several multiyear tasks that address high-priority waste remediation problems involving high-level, low-level, transuranic, hazardous, and mixed (radioactive and hazardous) wastes. The ESP supports applied research and development (R & D) leading to the demonstration or use of these separations technologies by other organizations within the Department of Energy (DOE), Office of Environmental Management.

  4. Underwater Acoustic Communication Based on Pattern Time Delay Shift Coding Scheme

    Institute of Scientific and Technical Information of China (English)

    YIN Jing-wei; HUI Jun-ying; HUI Juan; YAO Zhi-xiang; WANG Yi-lin

    2006-01-01

    Underwater acoustic communication based on Pattern Time Delay Shift Coding (PDS) communication scheme is studied. The time delay shift values of the pattern are used to encode the digital information in the PDS scheme, which belongs to the Pulse Position Modulation (PPM). The duty cycle of the PDS scheme is small, so it can economize the power for communication. By use of different patterns for code division and different frequencies for channel division, the communication system is capable of mitigating the inter-symbol interference (ISI) caused by the multipath channel. The data rate of communication is 1000 bits/s at 8 kHz bandwidth. The receiver separates the channels by means of band-pass filters, and performs decoding by 4 copy-correlators to estimate the time delay shift value. Based on the theoretical analysis and numerical simulations, the PDS scheme is shown to be a robust and effective approach for underwater acoustic communication.

  5. Independence of echo-threshold and echo-delay in the barn owl.

    Directory of Open Access Journals (Sweden)

    Brian S Nelson

    Full Text Available Despite their prevalence in nature, echoes are not perceived as events separate from the sounds arriving directly from an active source, until the echo's delay is long. We measured the head-saccades of barn owls and the responses of neurons in their auditory space-maps while presenting a long duration noise-burst and a simulated echo. Under this paradigm, there were two possible stimulus segments that could potentially signal the location of the echo. One was at the onset of the echo; the other, after the offset of the direct (leading sound, when only the echo was present. By lengthening the echo's duration, independently of its delay, spikes and saccades were evoked by the source of the echo even at delays that normally evoked saccades to only the direct source. An echo's location thus appears to be signaled by the neural response evoked after the offset of the direct sound.

  6. Measuring gravitational lens time delays using low-resolution radio monitoring observations

    CERN Document Server

    Gurkan, G; Koopmans, L V E; Fassnacht, C D; Alba, A Berciano

    2014-01-01

    Obtaining lensing time delay measurements requires long-term monitoring campaigns with a high enough resolution (< 1 arcsec) to separate the multiple images. In the radio, a limited number of high-resolution interferometer arrays make these observations difficult to schedule. To overcome this problem, we propose a technique for measuring gravitational time delays which relies on monitoring the total flux density with low-resolution but high-sensitivity radio telescopes to follow the variation of the brighter image. This is then used to trigger high-resolution observations in optimal numbers which then reveal the variation in the fainter image. We present simulations to assess the efficiency of this method together with a pilot project observing radio lens systems with the Westerbork Synthesis Radio Telescope (WSRT) to trigger Very Large Array (VLA) observations. This new method is promising for measuring time delays because it uses relatively small amounts of time on high-resolution telescopes. This will b...

  7. Time delay in thin slabs with self-focusing Kerr-type nonlinearity

    Science.gov (United States)

    Isić, G.; Milanović, V.; Radovanović, J.; Ikonić, Z.; Indjin, D.; Harrison, P.

    2008-03-01

    Time delays for an intense transverse electric (TE) wave propagating through a Kerr-type nonlinear slab are investigated. The relation between the bidirectional group delay and the dwell time is derived and it is shown that the difference between them can be separated into three terms. The first one is the familiar self-interference time, due to the dispersion of the medium surrounding the slab. The other two terms are caused by the nonlinearity and oblique incidence of the TE wave. It is shown that the electric field distribution along the slab may be expressed in terms of Jacobi elliptic functions while the phase difference introduced by the slab is given in terms of incomplete elliptic integrals. The expressions for the field-intensity-dependent complex reflection and transmission coefficients are derived and the multivalued oscillatory behavior of the delay times for the case of a thin slab is demonstrated.

  8. Oscillation for equations with positive and negative coefficients and with distributed delay I: General results

    Directory of Open Access Journals (Sweden)

    Leonid Berezansky

    2003-02-01

    Full Text Available We study a scalar delay differential equation with a bounded distributed delay, $$ dot{x}(t+ int_{h(t}^t x(s,d_s R(t,s - int_{g(t}^t x(s,d_s T(t,s=0, $$ where $R(t,s$, $T(t,s$ are nonnegative nondecreasing in $s$ for any $t$, $$ R(t,h(t=T(t,g(t=0, quad R(t,s geq T(t,s. $$ We establish a connection between non-oscillation of this differential equation and the corresponding differential inequalities, and between positiveness of the fundamental function and the existence of a nonnegative solution for a nonlinear integral inequality that constructed explicitly. We also present comparison theorems, and explicit non-oscillation and oscillation results. In a separate publication (part II, we will consider applications of this theory to differential equations with several concentrated delays, integrodifferential, and mixed equations.

  9. UAS Air Traffic Controller Acceptability Study-2: Effects of Communications Delays and Winds in Simulation

    Science.gov (United States)

    Comstock, James R., Jr.; Ghatas, Rania W.; Consiglio, Maria C.; Chamberlain, James P.; Hoffler, Keith D.

    2016-01-01

    This study evaluated the effects of Communications Delays and Winds on Air Traffic Controller ratings of acceptability of horizontal miss distances (HMDs) for encounters between UAS and manned aircraft in a simulation of the Dallas-Ft. Worth East-side airspace. Fourteen encounters per hour were staged in the presence of moderate background traffic. Seven recently retired controllers with experience at DFW served as subjects. Guidance provided to the UAS pilots for maintaining a given HMD was provided by information from self-separation algorithms displayed on the Multi-Aircraft Simulation System. Winds tested did not affect the acceptability ratings. Communications delays tested included 0, 400, 1200, and 1800 msec. For longer communications delays, there were changes in strategy and communications flow that were observed and reported by the controllers. The aim of this work is to provide useful information for guiding future rules and regulations applicable to flying UAS in the NAS.

  10. Speed Measurement and Motion Analysis of Chang'E-3 Rover Based on Differential Phase Delay

    Science.gov (United States)

    Chao, Pan; Qing-hui, Liu; Xin, Zheng; Qing-bao, He; Ya-jun, Wu

    2016-04-01

    On 14th December 2013, the Chang'E-3 made a successful soft landing on the lunar surface, and then carried out the tasks of separating the lander and the rover, and taking pictures of each other. With the same beam VLBI (Very Long Baseline Interferometry) technique to observe the signals transmitted by the lander and the rover simultaneously, the differential phase delay between them is calculated, which can reflect the minor changes of the rover's position on a scale of a few centimeters. Based on the high sensitivity of differential phase delay, the rover's speeds during 5 movements are obtained with an average of 0.056 m/s. The relationship between the rover's shake in the moving process and the lunar terrain is analyzed by using the spectrum of the residual of the differential phase delay after the first-order polynomial fitting.

  11. Delayed Random Walks: Modeling Human Posture Control

    Science.gov (United States)

    Ohira, Toru

    1998-03-01

    We consider a phenomenological description of a noisy trajectory which appears on a stabiliogram platform during human postural sway. We hypothesize that this trajectory arises due to a mixture of uncontrollable noise and a corrective delayed feedback to an upright position. Based on this hypothesis, we model the process with a biased random walk whose transition probability depends on its position at a fixed time delay in the past, which we call a delayed random walk. We first introduce a very simple model (T. Ohira and J. G. Milton, Phys.Rev.E. 52), 3277, (1995), which can nevertheless capture the rough qualitative features of the two--point mean square displacement of experimental data with reasonable estimation of delay time. Then, we discuss two approaches toward better capturing and understanding of the experimental data. The first approach is an extension of the model to include a spatial displacement threshold from the upright position below which no or only weak corrective feedback motion takes place. This can be incorporated into an extended delayed random walk model. Numerical simulations show that this extended model can better capture the three scaling region which appears in the two--point mean square displacement. The other approach studied the autocorrelation function of the experimental data, which shows oscillatory behavior. We recently investigated a delayed random walk model whose autocorrelation function has analytically tractable oscillatory behavior (T. Ohira, Phys.Rev.E. 55), R1255, (1997). We discuss how this analytical understanding and its application to delay estimation (T. Ohira and R. Sawatari, Phys.Rev.E. 55), R2077, (1997) could possibly be used to further understand the postural sway data.

  12. Delay differential analysis of time series.

    Science.gov (United States)

    Lainscsek, Claudia; Sejnowski, Terrence J

    2015-03-01

    Nonlinear dynamical system analysis based on embedding theory has been used for modeling and prediction, but it also has applications to signal detection and classification of time series. An embedding creates a multidimensional geometrical object from a single time series. Traditionally either delay or derivative embeddings have been used. The delay embedding is composed of delayed versions of the signal, and the derivative embedding is composed of successive derivatives of the signal. The delay embedding has been extended to nonuniform embeddings to take multiple timescales into account. Both embeddings provide information on the underlying dynamical system without having direct access to all the system variables. Delay differential analysis is based on functional embeddings, a combination of the derivative embedding with nonuniform delay embeddings. Small delay differential equation (DDE) models that best represent relevant dynamic features of time series data are selected from a pool of candidate models for detection or classification. We show that the properties of DDEs support spectral analysis in the time domain where nonlinear correlation functions are used to detect frequencies, frequency and phase couplings, and bispectra. These can be efficiently computed with short time windows and are robust to noise. For frequency analysis, this framework is a multivariate extension of discrete Fourier transform (DFT), and for higher-order spectra, it is a linear and multivariate alternative to multidimensional fast Fourier transform of multidimensional correlations. This method can be applied to short or sparse time series and can be extended to cross-trial and cross-channel spectra if multiple short data segments of the same experiment are available. Together, this time-domain toolbox provides higher temporal resolution, increased frequency and phase coupling information, and it allows an easy and straightforward implementation of higher-order spectra across time

  13. Delay Differential Analysis of Time Series

    Science.gov (United States)

    Lainscsek, Claudia; Sejnowski, Terrence J.

    2015-01-01

    Nonlinear dynamical system analysis based on embedding theory has been used for modeling and prediction, but it also has applications to signal detection and classification of time series. An embedding creates a multidimensional geometrical object from a single time series. Traditionally either delay or derivative embeddings have been used. The delay embedding is composed of delayed versions of the signal, and the derivative embedding is composed of successive derivatives of the signal. The delay embedding has been extended to nonuniform embeddings to take multiple timescales into account. Both embeddings provide information on the underlying dynamical system without having direct access to all the system variables. Delay differential analysis is based on functional embeddings, a combination of the derivative embedding with nonuniform delay embeddings. Small delay differential equation (DDE) models that best represent relevant dynamic features of time series data are selected from a pool of candidate models for detection or classification. We show that the properties of DDEs support spectral analysis in the time domain where nonlinear correlation functions are used to detect frequencies, frequency and phase couplings, and bispectra. These can be efficiently computed with short time windows and are robust to noise. For frequency analysis, this framework is a multivariate extension of discrete Fourier transform (DFT), and for higher-order spectra, it is a linear and multivariate alternative to multidimensional fast Fourier transform of multidimensional correlations. This method can be applied to short or sparse time series and can be extended to cross-trial and cross-channel spectra if multiple short data segments of the same experiment are available. Together, this time-domain toolbox provides higher temporal resolution, increased frequency and phase coupling information, and it allows an easy and straightforward implementation of higher-order spectra across time

  14. Facilitating tolerance of delayed reinforcement during functional communication training.

    Science.gov (United States)

    Fisher, W W; Thompson, R H; Hagopian, L P; Bowman, L G; Krug, A

    2000-01-01

    Few clinical investigations have addressed the problem of delayed reinforcement. In this investigation, three individuals whose destructive behavior was maintained by positive reinforcement were treated using functional communication training (FCT) with extinction (EXT). Next, procedures used in the basic literature on delayed reinforcement and self-control (reinforcer delay fading, punishment of impulsive responding, and provision of an alternative activity during reinforcer delay) were used to teach participants to tolerate delayed reinforcement. With the first case, reinforcer delay fading alone was effective at maintaining low rates of destructive behavior while introducing delayed reinforcement. In the second case, the addition of a punishment component reduced destructive behavior to near-zero levels and facilitated reinforcer delay fading. With the third case, reinforcer delay fading was associated with increases in masturbation and head rolling, but prompting and praising the individual for completing work during the delay interval reduced all problem behaviors and facilitated reinforcer delay fading.

  15. Lunar Soil Particle Separator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Soil Particle Separator (LSPS) is an innovative method to beneficiate soil prior to in-situ resource utilization (ISRU). The LSPS improves ISRU oxygen...

  16. Selective Photoinitiated Electrophoretic Separator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To address NASA Johnson Space Center needs for gas separation and collection technology for lunar in-situ resource utilization, Physical Optics Corporation (POC)...

  17. Magnetic separation in microfluidic systems

    DEFF Research Database (Denmark)

    Smistrup, Kristian

    2007-01-01

    This Ph.D. thesis presents theory, modeling, design, fabrication, experiments and results for microfluidic magnetic separators. A model for magnetic bead movement in a microfluidic channel is presented, and the limits of the model are discussed. The effective magnetic field gradient is defined...... for fabrication of silicon based systems. This fabrication scheme is explained, and it is shown how, it is applied with variations for several designs of magnetic separators. An experimental setup for magnetic separation experiments has been developed. It has been coupled with an image analysis program....... It is shown conceptually how such a system can be applied for parallel biochemical processing in a microfluidic system. ’Passive’ magnetic separators are presented, where on-chip soft magnetic elements are magnetized by an external magnetic field and create strong magnetic fields and gradients inside...

  18. Chiral separation of agricultural fungicides.

    Science.gov (United States)

    Pérez-Fernández, Virginia; García, Maria Ángeles; Marina, Maria Luisa

    2011-09-23

    Fungicides are very important and diverse environmental and agricultural concern species. Their determination in commercial formulations or environmental matrices, requires highly efficient, selective and sensitive methods. A significant number of these chemicals are chiral with the activity residing usually in one of the enantiomers. The different toxicological and degradation behavior observed in many cases for fungicide enantiomers, results in the need to investigate them separately. For this purpose, separation techniques such as GC, HPLC, supercritical fluid chromatography (SFC) and CE have widely been employed although, at present, HPLC still dominates chromatographic chiral analysis of fungicides. This review covers the literature concerning the enantiomeric separation of fungicides usually employed in agriculture grouping the chiral separation methodologies developed for their analysis in environmental, biological, and food samples.

  19. Lunar Soil Particle Separator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Soil Particle Separator (LSPS) is an innovative method to beneficiate soil prior to in-situ resource utilization (ISRU). The LSPS can improve ISRU oxygen...

  20. Phase separation during radiation crosslinking of unsaturated polyester resin

    Science.gov (United States)

    Pucić, Irina; Ranogajec, Franjo

    2003-06-01

    Phase separation during radiation-initiated crosslinking of unsaturated polyester resin was studied. Residual reactivity of liquid phases and gels of partially cured samples was determined by DSC. Uncured resin and liquid phases showed double reaction exotherm, gels had a single maximum that corresponded to higher-temperature maximum of liquid parts. The lower-temperature process was attributed to styrene-polyester copolymerization. At higher temperatures, polyester unsaturations that remained unreacted due to microgel formation homopolymerized. FTIR revealed different composition of phases. In thicker samples, reaction heat influenced microgel formation causing delayed appearance of gel and faster increase in conversion.

  1. Ataxia telangiectasia: presentation and diagnostic delay.

    Science.gov (United States)

    Devaney, Rebecca; Pasalodos, Sara; Suri, Mohnish; Bush, Andy; Bhatt, Jayesh M

    2017-04-01

    Ataxia telangiectasia (A-T) is a rare progressive, multisystem genetic disease. Families of children with ultra-rare diseases often experience significant diagnostic delays. We reviewed the diagnostic process for A-T in order to identify causes of delay in an attempt to facilitate earlier identification of A-T in the future. A retrospective case note review of 79 children at the National Paediatric A-T clinic seen since May 2009. Data were collected on the nature and age of initial symptoms, the age at first presentation, measurement of alpha feto-protein (AFP) and age of genetic diagnostic confirmation. At presentation, 71 children (90%) had ataxia. The median presentation delay (from first parental concern to presentation) was 8 months (range 0-118 months), and the median diagnostic delay (genetic confirmation of diagnosis) was 12 months (range 1-109 months). There are significant delays in presentation and diagnostic confirmation of A-T. A greater awareness of A-T and early measurement of AFP may help to improve this. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  2. Wigner photoemission time delay from endohedral anions

    Science.gov (United States)

    Kumar, Ashish; Varma, Hari R.; Deshmukh, Pranawa C.; Manson, Steven T.; Dolmatov, Valeriy K.; Kheifets, Anatoli

    2016-10-01

    Characteristic features of Wigner photoemission time delay from endohedral anions A@C60q along with their dependence on the anion charge q are unraveled. Specifically, significant enhancement of the time delay in the innermost dipole photoionization channels near threshold is found, owing to the presence of the Coulomb confined resonances (CRs). Moreover, it is shown that interchannel coupling of the inner-shell Coulomb CRs with outer-shell photoionization channels results in resonantly enhanced time delay in the release of the outer-shell photoelectron well above, several hundreds eV, the outer-shell thresholds. It is also demonstrated that, and explained why, photoionization cross sections of the innermost subshells as well as outer subshells (near the inner-subshell threshold) depends only very weakly on the anion charge q , but the dependence of the corresponding time delays on q can be significant. Furthermore, Coulomb CRs are found to emerge in the innermost quadrupole photoionization channels as well, thereby causing considerable time delay in the quadrupole photoemission. These findings are illustrated in calculations of the photoionization of inner and outer subshells of the endohedral anions Ne@C60-1 and Ne@C60-5 that were chosen as case studies.

  3. Time Delay for the Dirac Equation

    Science.gov (United States)

    Naumkin, Ivan; Weder, Ricardo

    2016-10-01

    We consider time delay for the Dirac equation. A new method to calculate the asymptotics of the expectation values of the operator {intlimits0 ^{∞}e^{iH0t}ζ(\\vert x\\vert /R) e^{-iH0t}dt}, as {R → ∞}, is presented. Here, H 0 is the free Dirac operator and {ζ(t)} is such that {ζ(t) = 1} for {0 ≤ t ≤ 1} and {ζ(t) = 0} for {t > 1}. This approach allows us to obtain the time delay operator {δ {T}(f)} for initial states f in {{H} 2^{3/2+ɛ}({R}3;{C}4)}, {ɛ > 0}, the Sobolev space of order {3/2+ɛ} and weight 2. The relation between the time delay operator {δ{T}(f)} and the Eisenbud-Wigner time delay operator is given. In addition, the relation between the averaged time delay and the spectral shift function is presented.

  4. Theory of attosecond delays in molecular photoionization

    Science.gov (United States)

    Baykusheva, Denitsa; Wörner, Hans Jakob

    2017-03-01

    We present a theoretical formalism for the calculation of attosecond delays in molecular photoionization. It is shown how delays relevant to one-photon-ionization, also known as Eisenbud-Wigner-Smith delays, can be obtained from the complex dipole matrix elements provided by molecular quantum scattering theory. These results are used to derive formulae for the delays measured by two-photon attosecond interferometry based on an attosecond pulse train and a dressing femtosecond infrared pulse. These effective delays are first expressed in the molecular frame where maximal information about the molecular photoionization dynamics is available. The effects of averaging over the emission direction of the electron and the molecular orientation are introduced analytically. We illustrate this general formalism for the case of two polyatomic molecules. N2O serves as an example of a polar linear molecule characterized by complex photoionization dynamics resulting from the presence of molecular shape resonances. H2O illustrates the case of a non-linear molecule with comparably simple photoionization dynamics resulting from a flat continuum. Our theory establishes the foundation for interpreting measurements of the photoionization dynamics of all molecules by attosecond metrology.

  5. Separators for Lithium Ion Batteries

    Institute of Scientific and Technical Information of China (English)

    G.C.Li; H.P.Zhang; Y.P.Wu

    2007-01-01

    1 Results A separator for rechargeable batteries is a microporous membrane placed between electrodes of opposite polarity, keeping them apart to prevent electrical short circuits and at the same time allowing rapid transport of lithium ions that are needed to complete the circuit during the passage of current in an electrochemical cell, and thus plays a key role in determining the performance of the lithium ion battery. Here provides a comprehensive overview of various types of separators for lithium io...

  6. Lithium isotope separation by laser

    Energy Technology Data Exchange (ETDEWEB)

    Arisawa, T.; Maruyama, Y.; Suzuki, Y.; Shiba, K.

    1982-01-01

    A lithium isotope separation was performed using a laser isotope separation method. It was found that the lithium atoms with a natural isotopic abundance enhanced its /sup 6/Li concentration up to over 90% by tuning the laser wavelength to the /sup 2/Psub(1/2) of /sup 6/Li. Too high power, however, leads to a loss of enrichment due to the power broadening effect which was analysed by the equation of motion of density matrices.

  7. Fuel-Cell Water Separator

    Science.gov (United States)

    Burke, Kenneth Alan; Fisher, Caleb; Newman, Paul

    2010-01-01

    The main product of a typical fuel cell is water, and many fuel-cell configurations use the flow of excess gases (i.e., gases not consumed by the reaction) to drive the resultant water out of the cell. This two-phase mixture then exits through an exhaust port where the two fluids must again be separated to prevent the fuel cell from flooding and to facilitate the reutilization of both fluids. The Glenn Research Center (GRC) has designed, built, and tested an innovative fuel-cell water separator that not only removes liquid water from a fuel cell s exhaust ports, but does so with no moving parts or other power-consuming components. Instead it employs the potential and kinetic energies already present in the moving exhaust flow. In addition, the geometry of the separator is explicitly intended to be integrated into a fuel-cell stack, providing a direct mate with the fuel cell s existing flow ports. The separator is also fully scalable, allowing it to accommodate a wide range of water removal requirements. Multiple separators can simply be "stacked" in series or parallel to adapt to the water production/removal rate. GRC s separator accomplishes the task of water removal by coupling a high aspect- ratio flow chamber with a highly hydrophilic, polyethersulfone membrane. The hydrophilic membrane readily absorbs and transports the liquid water away from the mixture while simultaneously resisting gas penetration. The expansive flow path maximizes the interaction of the water particles with the membrane while minimizing the overall gas flow restriction. In essence, each fluid takes its corresponding path of least resistance, and the two fluids are effectively separated. The GRC fuel-cell water separator has a broad range of applications, including commercial hydrogen-air fuel cells currently being considered for power generation in automobiles.

  8. Development of Radiochemical Separation Technology

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eil Hee; Kim, K. W.; Yang, H. B. (and others)

    2007-06-15

    This project of the second phase was aimed at the development of basic unit technologies for advanced partitioning, and the application tests of pre-developed partitioning technologies for separation of actinides by using a simulated multi-component radioactive waste containing Am, Np, Tc, U and so on. The goals for recovery yield of TRU, and for purity of Tc are high than 99% and about 99%, respectively. The work scopes and contents were as follows. 1). For the development of basic unit technologies for advanced partitioning. 1. Development of technologies for co-removal of TRU and for mutual separation of U and TRU with a reduction-complexation reaction. 2. Development of extraction system for high-acidity co-separation of An(+3) and Ln(+3) and its radiolytic evaluation. 3. Synthesis of extractants for the selective separation of An(+3) and its relevant extraction system development. 4. Development of a hybrid system for the recovery of noble metals and its continuous separation tests. 5. Development of electrolytic system for the decompositions of N-NO3 and N-NH3 compounds to nitrogen gas. 2). For the application test of pre-developed partitioning technologies for the separation of actinide elements in a simulated multi-component solution equivalent to HLW level. 1. Co-separation of Tc, Np and U by a (TBP-TOA)/NDD system. 2. Mutual-separation of Am, Cm and RE elements by a (Zr-DEHPA)/NDD system. All results will be used as the fundamental data for the development of advanced partitioning process in the future.

  9. Optics of mass separator I

    Energy Technology Data Exchange (ETDEWEB)

    Balestrini, S.J.

    1981-07-01

    The ion optics of an existing mass separator are documented. The elctrostatic and magnetic stages are analyzed theoretically, both separately and in combination, by paying particular attention to the ion trajectories, the linear and angular magnifications, and the dispersion. The possibility of converting the magnet into a tunable unit by means of current-carrying elements in the gap is demonstrated. The feasibility of correction coils constructed from printed circuit board is shown.

  10. Memory processes in delayed spatial discriminations: response intentions or response mediation?

    Science.gov (United States)

    Urcuioli, P J; DeMarse, T B

    1997-05-01

    Pigeons were trained on a pair-comparison task in which left versus right choices were reinforced following different sequences of two center-key stimuli. Choice accuracy was higher when retention intervals occurred after the entire sequence than when they separated the two stimuli comprising it, and this effect occurred independently of whether the initial and terminal stimuli came from the same or different dimensions. The initial stimulus from the prior trial was a source of proactive interference only in groups for which the retention interval separated the two sequence stimuli. By contrast, differential delay-interval behavior was observed only in groups for which the retention interval followed presentation of the entire sequence. These results indicate that coding processes in delayed discriminations are influenced by the location of the retention interval, and that response mediation affects retention performances if the reinforced choice can be determined prior to the interval.

  11. Observational selection biases in time-delay strong lensing and their impact on cosmography

    CERN Document Server

    Collett, Thomas E

    2016-01-01

    Inferring cosmological parameters from time-delay strong lenses requires a significant investment of telescope time; it is therefore tempting to focus on the systems with the brightest sources, the highest image multiplicities and the widest image separations. We investigate if this selection bias can influence the properties of the lenses studied and the cosmological parameters that are inferred. Using a population of lenses with ellipsoidal powerlaw density profiles, we build a sample of double and quadruple image systems. Assuming reasonable thresholds on image separation and flux, based on current lens monitoring campaigns, we find that the typical density profile slopes of monitorable lenses are significantly shallower than the input ensemble. From a sample of quadruple image lenses we find that this selection function can introduce a 3.5% bias on the inferred time-delay distances if the ensemble of deflector properties is used as a prior for a cosmographical analysis. This bias remains at the 2.4% level...

  12. Investigation of several passive and active methods for turbulent flow separation control

    Science.gov (United States)

    Lin, J. C.; Howard, F. G.; Bushnell, D. M.; Selby, G. V.

    1990-01-01

    Relative performance of several passive and active methods for controlling two-dimensional turbulent separated flow associated with a curved backward-facing ramp were investigated at low speeds. Surface static pressure measurement and oil flow visualization results indicate that submerged vortex generators, vortex generator jets, elongated arches at +-alpha, and large-eddy breakup devices at +-alpha placed near the baseline separation location reduce flow separation and increase pressure recovery. Spanwise cylinders reduce flow separation but decrease pressure recovery downstream. Arches with alpha = 0 deg, Helmholtz resonators, and Viets' fluidic flappers examined so far have no significant effect in reducing separation. Wall cooling computation indicates that separation delay on a partially cooled ramp is nearly the same as on a fully-cooled ramp while minimizing the frictional drag increase associated with the wall cooling process.

  13. Adaptive synchronization of neural networks with time-varying delay and distributed delay

    Science.gov (United States)

    Wang, Kai; Teng, Zhidong; Jiang, Haijun

    2008-01-01

    In this paper, the adaptive synchronization of neural networks with time-varying delay and distributed delay is discussed. Based on the LaSalle invariant principle of functional differential equations and the adaptive feedback control technique, some sufficient conditions for adaptive synchronization of such a system are obtained. Finally, a numerical example is given to show the effectiveness of the proposed synchronization method.

  14. Effect of Delay on Children's Delay-Execute Prospective Memory Performance

    Science.gov (United States)

    Rendell, Peter G.; Vella, Melissa J.; Kliegel, Matthias; Terrett, Gill

    2009-01-01

    To date, little work has been done investigating prospective memory in children, particularly using a delay-execute paradigm. Two experiments were conducted to investigate this issue with children aged 5-11 years. While playing a computer driving game, children's ability to carry out a delayed intention either immediately a target cue appeared or…

  15. Robust delay-dependent feedforward control of neutral time-delay systems via dynamic IQCs

    Science.gov (United States)

    Ucun, L.; Küçükdemiral, I. B.

    2014-05-01

    This paper studies the design problem of delay-dependent ? based robust and optimal feedforward controller design for a class of time-delay control systems having state, control and neutral type delays which are subject to norm-bounded uncertainties and ? type measurable or observable disturbance signals. Two independent loops which include state-feedback and dynamic feedforward controller form the basis of the proposed control scheme in this study. State-feedback controller is generally used in stabilisation of the nominal delay-free system, whereas the feedforward controller is used for improving disturbance attenuation performance of the overall system. In order to obtain less conservative results, the delay and parametric uncertainty effects are treated in operator view point and represented by frequency-dependent (dynamic) integral quadratic constraints (IQCs). Moreover, sufficient delay-dependent criterion is developed in terms of linear matrix inequalities (LMIs) such that the time-delay system having parametric uncertainties is guaranteed to be asymptotically stable with minimum achievable disturbance attenuation level. Plenty of numerical examples are provided at the end, in order to illustrate the efficiency of the proposed technique. The achieved results on minimum achievable disturbance attenuation level and maximum allowable delay bounds are exhibited to be less conservative in comparison to those of controllers having only feedback loop.

  16. A Comparison of Motor Delays in Young Children: Autism Spectrum Disorder, Developmental Delay, and Developmental Concerns

    Science.gov (United States)

    Provost, Beth; Lopez, Brian R.; Heimerl, Sandra

    2007-01-01

    This study assessed motor delay in young children 21-41 months of age with autism spectrum disorder (ASD), and compared motor scores in children with ASD to those of children without ASD. Fifty-six children (42 boys, 14 girls) were in three groups: children with ASD, children with developmental delay (DD), and children with developmental concerns…

  17. Controllability of Linear Discrete-Time Systems with Both Delayed States and Delayed Inputs

    Directory of Open Access Journals (Sweden)

    Hong Shi

    2013-01-01

    Full Text Available The controllability issues for discrete-time linear systems with delay in state and control are addressed. By introducing a new concept, the controllability realization index (CRI, the characteristic of controllability is revealed. An easily testable necessary and sufficient condition for the controllability of discrete-time linear systems with state and control delay is established.

  18. Delay-Dependent Exponential Stability Criterion for BAM Neural Networks with Time-Varying Delays

    Institute of Scientific and Technical Information of China (English)

    Wei-Wei Su; Yi-Ming Chen

    2008-01-01

    By employing the Lyapunov stability theory and linear matrix inequality (LMI) technique, delay dependent stability criterion is derived to ensure the exponential stability of bi-directional associative memory (BAM) neural networks with time-varying delays. The proposed condition can be checked easily by LMI control toolbox in Matlab. A numerical example is given to demonstrate the effectiveness of our results.

  19. A DELAY-DEPENDENT STABILITY CRITERION FOR NONLINEAR STOCHASTIC DELAY-INTEGRO-DIFFERENTIAL EQUATIONS

    Institute of Scientific and Technical Information of China (English)

    Niu Yuanling; Zhang Chengjian; Duan Jinqiao

    2011-01-01

    A type of complex systems under both random influence and memory effects is considered.The systems are modeled by a class of nonlinear stochastic delay-integrodifferential equations.A delay-dependent stability criterion for such equations is derived under the condition that the time lags are small enough.Numerical simulations are presented to illustrate the theoretical result.

  20. The Effects of Delay of Feedback on a Delayed Concept Formation Transfer Task.

    Science.gov (United States)

    Schroth, Marvin L.

    1992-01-01

    Delay and completeness of verbal information feedback were investigated within a transfer of learning paradigm involving concept formation. An experiment with 192 undergraduates indicates that, although delay of feedback (up to 30 seconds) slows speed of learning on the initial task, it has positive effects on the transfer task. (SLD)

  1. Separation mechanisms and fluid flow in oil/water separation

    Energy Technology Data Exchange (ETDEWEB)

    Celius, H.K.; Knudsen, B. [IKU Petroleumsforskning A/S, Trondheim (Norway); Hafskjold, B.; Hansen, E.W. [Selskapet for Industriell og Teknisk Forskning, Trondheim (Norway)

    1996-12-31

    This paper describes work aimed at physical and numerical modeling of separation rates of oil/water systems in order to establish better tools for design and operation of offshore operators. This work aims to integrate the chemical and physical phenomena behind coalescence and settling with those of fluid flow in the system, in order to develop tools for design and operational analysis of separation equipment. The work includes the development of a high pressure, bench-scale test rig to perform separation tests on live oil and water samples, and a rationale in the form of a computer code that can be used to interpret the test results and transform them to a form siutable for operational purposes. This involves a formulation of a mathematical description of the chemical and physical mechanisms behind the emulsification and separation process, and to establish a link to the hydrdynamic properties of the separator vessel. The Emucol computer program is used in the analysis. 12 refs., 5 figs.

  2. Delayed Sequential Coding of Correlated Sources

    CERN Document Server

    Ma, Nan; Ishwar, Prakash

    2007-01-01

    Motivated by video coding applications, we study the problem of sequential coding of correlated sources with (noncausal) encoding and/or decoding frame-delays. The fundamental tradeoffs between individual frame rates, individual frame distortions, and encoding/decoding frame-delays are derived in terms of a single-letter information-theoretic characterization of the rate-distortion region for general inter-frame source correlations and certain types of (potentially frame-specific and coupled) single-letter fidelity criteria. For video sources which are spatially stationary memoryless and temporally Gauss--Markov, MSE frame distortions, and a sum-rate constraint, our results expose the optimality of differential predictive coding among all causal sequential coders. Somewhat surprisingly, causal sequential encoding with one-step delayed noncausal sequential decoding can exactly match the sum-rate-MSE performance of joint coding for all nontrivial MSE-tuples satisfying certain positive semi-definiteness conditio...

  3. Elimination of Delays to Oculomotor Research Equipment

    Directory of Open Access Journals (Sweden)

    Saulius Niauronis

    2012-04-01

    Full Text Available Optic stimulus used for human oculomotor system or eye-hand coordination researches is often represented on a computer screen. They must be synchronised with the eye tracker to achieve the accurate results of the conducted experiments. Relation between stimulus presence and eye image capturing times can be defined only with reference to knowledge of all system delays. The suggested research evaluates our eye tracking system delay and propose a practical method for measuring and evaluating delays to the computer graphic subsystem. Experimental research shows that LC Technologies eye tracker reports gaze angle with 28 ms lag and the average stimulus lag of the computer graphic subsystem is 9,5 ms.Article in Lithuanian

  4. Time delay measurement in the frequency domain

    Energy Technology Data Exchange (ETDEWEB)

    Durbin, Stephen M., E-mail: durbin@purdue.edu; Liu, Shih-Chieh [Purdue University, West Lafayette, IN 47907 (United States); Dufresne, Eric M.; Li, Yuelin; Wen, Haidan [Argonne National Laboratory, Argonne, IL 60439 (United States)

    2015-08-06

    A simple frequency domain technique for determining the time delay between laser pump and X-ray probe pulses achieves 1 ps resolution even for ∼100 ps synchrotron pulses, permitting improved pump–probe characterization of ultrafast processes. Pump–probe studies at synchrotrons using X-ray and laser pulses require accurate determination of the time delay between pulses. This becomes especially important when observing ultrafast responses with lifetimes approaching or even less than the X-ray pulse duration (∼100 ps). The standard approach of inspecting the time response of a detector sensitive to both types of pulses can have limitations due to dissimilar pulse profiles and other experimental factors. Here, a simple alternative is presented, where the frequency response of the detector is monitored versus time delay. Measurements readily demonstrate a time resolution of ∼1 ps. Improved precision is possible by simply extending the data acquisition time.

  5. Time-delayed autosynchronous swarm control.

    Science.gov (United States)

    Biggs, James D; Bennet, Derek J; Dadzie, S Kokou

    2012-01-01

    In this paper a general Morse potential model of self-propelling particles is considered in the presence of a time-delayed term and a spring potential. It is shown that the emergent swarm behavior is dependent on the delay term and weights of the time-delayed function, which can be set to induce a stationary swarm, a rotating swarm with uniform translation, and a rotating swarm with a stationary center of mass. An analysis of the mean field equations shows that without a spring potential the motion of the center of mass is determined explicitly by a multivalued function. For a nonzero spring potential the swarm converges to a vortex formation about a stationary center of mass, except at discrete bifurcation points where the center of mass will periodically trace an ellipse. The analytical results defining the behavior of the center of mass are shown to correspond with the numerical swarm simulations.

  6. Why do delayed summaries improve metacomprehension accuracy?

    Science.gov (United States)

    Anderson, Mary C M; Thiede, Keith W

    2008-05-01

    We showed that metacomprehension accuracy improved when participants (N=87 college students) wrote summaries of texts prior to judging their comprehension; however, accuracy only improved when summaries were written after a delay, not when written immediately after reading. We evaluated two hypotheses proposed to account for this delayed-summarization effect (the accessibility hypothesis and the situation model hypothesis). The data suggest that participants based metacomprehension judgments more on the gist of texts when they generated summaries after a delay; whereas, they based judgments more on details when they generated summaries immediately after reading. Focusing on information relevant to the situation model of a text (the gist of a text) produced higher levels of metacomprehension accuracy, which is consistent with situation model hypothesis.

  7. Delay estimation for CMOS functional cells

    DEFF Research Database (Denmark)

    Madsen, Jan

    1991-01-01

    Presents a new RC tree network model for delay estimation of CMOS functional cells. The model is able to reflect topological changes within a cell, which is of particular interest when doing performance driven layout synthesis. Further, a set of algorithms to perform worst case analysis on arbitr......Presents a new RC tree network model for delay estimation of CMOS functional cells. The model is able to reflect topological changes within a cell, which is of particular interest when doing performance driven layout synthesis. Further, a set of algorithms to perform worst case analysis...... on arbitrary CMOS functional cells using the proposed delay model, is presented. Both model and algorithms have been implemented as a part of a cell compiler (CELLO) working in an experimental silicon compiler environment....

  8. Delayed reconstruction of a quadriceps tendon.

    Science.gov (United States)

    Pocock, C A J; Trikha, S P; Bell, J S P

    2008-01-01

    Rupture of the quadriceps tendon is an uncommon injury and rapid diagnosis is important because delay in surgical repair generally is believed to adversely affect outcome. One study of 20 patients suggests repair should be done during the first 48 to 72 hours postinjury to achieve a successful outcome and late repair led to unsatisfactory recovery. Cases of delayed tendon repair have been reported, the longest to our knowledge being 11 months before surgical intervention. We present a case of successful outcome of a quadriceps tendon rupture reconstructed at least 8 years after occurrence and a review of the literature of delayed reconstructions. We show that successful restoration of extensor mechanism function can be achieved several years after tendon rupture.

  9. Delayed feedback control in quantum transport.

    Science.gov (United States)

    Emary, Clive

    2013-09-28

    Feedback control in quantum transport has been predicted to give rise to several interesting effects, among them quantum state stabilization and the realization of a mesoscopic Maxwell's daemon. These results were derived under the assumption that control operations on the system are affected instantaneously after the measurement of electronic jumps through it. In this contribution, I describe how to include a delay between detection and control operation in the master equation theory of feedback-controlled quantum transport. I investigate the consequences of delay for the state stabilization and Maxwell's daemon schemes. Furthermore, I describe how delay can be used as a tool to probe coherent oscillations of electrons within a transport system and how this formalism can be used to model finite detector bandwidth.

  10. Reasons for diagnostic delay in gynecological malignancies

    DEFF Research Database (Denmark)

    Vandborg, Mai Partridge; Christensen, René dePont Christensen; Kragstrup, Jakob;

    2011-01-01

    Aim The primary aim of this study was to identify and describe different delay types in women with gynecologic cancer, and to analyze the relationship between diagnostic delay and a number of characteristics for patients, cancers and the health care system. Setting A cohort study of women newly...... diagnosed with gynecological cancer at the Department of Gynecology and Obstetrics at Odense University Hospital (OUH) Denmark, during a 15-month period from October 1st 2006 to December 31st 2007. Method Data were obtained from four different questionnaires, the Electronic Patient Journal (EPJ......) and The Danish Gynecological Cancer Database (DGCD). 161 women were included; ovarian cancer: 63, endometrial cancer: 50, cervical cancer: 34 and vulvar cancer: 14. Outcome measures were different delay types counted in days and the influence of four clinical important variables: Presence of alarm symptoms, age...

  11. Opportunistic Secrecy with a Strict Delay Constraint

    CERN Document Server

    Khalil, Karim; Gamal, Hesham El; Youssef, Moustafa

    2009-01-01

    We investigate the delay limited secrecy capacity of the flat fading channel under two different assumptions on the available transmitter channel state information (CSI). The first scenario assumes perfect prior knowledge of both the main and eavesdropper channel gains. Here, upper and lower bounds on the delay limited secrecy capacity are derived, and shown to be tight in the high signal-to-noise ratio (SNR) regime. In the second scenario, only the main channel CSI is assumed to be available at the transmitter where, remarkably, we establish the achievability of a non-zero delay-limited secure rate, for a wide class of channel distributions, with a high probability. In the two cases, our achievability arguments are based on a novel two-stage key-sharing approach that overcomes the secrecy outage phenomenon observed in earlier works.

  12. Abdominal CT findings of delayed postoperative complications

    Energy Technology Data Exchange (ETDEWEB)

    Zissin, R.; Osadchy, A. [Sapir Medical Center, Dept. of Diagnostic Imaging, Kfar Saba (Israel)]. E-mail: zisinrivka@clalit.org.il; Gayer, G. [Assaf Harofe Medical Center, Dept. of Diagnostic Imaging, Zrifin (Israel)

    2007-10-15

    Despite progress in surgical techniques and modern medical treatment, postoperative complications occur not infrequently and vary according to type of surgery, clinical setting, and time elapsed since surgery. In general, they can be divided into early and delayed complications. Delayed postoperative complications can be classified as specific and nonspecific. The common nonspecific delayed complications are incisional hernia and postoperative bowel obstruction. Bowel obstruction can be further categorized as obstruction related to benign or neoplastic etiology, the latter occurring in oncology patients in whom the primary surgery was related to an underlying abdominal neoplasm. Gossypiboma is another, fortunately rare, postoperative complication. Specific complications appear after specific operations and include the following: Splenosis - following splenectomy. Retained gallstones and spilled gallstones - following cholecystectomy, mainly laparoscopic. Dropped appendicolith and stump appendicitis - following appendectomy, mainly laparoscopic. Obturation obstruction by a bezoar - following gastric surgery. Afferent loop syndrome (ALS) - following Bilroth II gastrectomy. (author)

  13. Delay-dependent robust stability of uncertain networked control systems with multiple state time-delays

    Institute of Scientific and Technical Information of China (English)

    Huaicheng YAN; Xinhan HUANG; Min WANG

    2007-01-01

    In this paper, delay-dependent robust stability for a class of uncertain networked control systems (NCSs)with multiple state time-delays is investigated. Modeling of multi-input and multi-output (MIMO) NCSs with networkinduced delays and uncertainties through new methods are proposed. Some new stability criteria in terms of LMIs are derived by using Lyapunov stability theory combined with linear matrix inequalities (LMIs) techniques. We analyze the delay-dependent asymptotic stability and obtain maximum allowable delay bound (MADB) for the NCSs with the proposed methods. Compared with the reported results, the proposed results obtain a much less conservative MADB which are more general. Numerical example and simulation is used to illustrate the effectiveness of the proposed methods.

  14. Classic conditioning in aged rabbits: delay, trace, and long-delay conditioning.

    Science.gov (United States)

    Solomon, P R; Groccia-Ellison, M E

    1996-06-01

    Young (0.5 years) and aged (2+, 3+, and 4+ years) rabbits underwent acquisition of the classically conditioned nictitating membrane response in a delay (500-ms conditioned stimulus [CS], 400-ms interstimulus interval [ISI]), long-delay (1,000-ms CS, 900-ms ISI), or trace (500-ms CS, 400-ms stimulus-free period) paradigm. Collapsing across age groups, there is a general tendency for animals to acquire trace conditioning more slowly than delay conditioning. Collapsing across conditioning paradigms, there is a general tendency for aged animals to acquire more slowly than younger animals. Of greater significance, however, are the age differences in the different conditioning paradigms. In the delay and long-delay paradigms, significant conditioning deficits first appeared in the 4(+)-year-old group. In the trace conditioning paradigm, significant conditioning deficits became apparent in the 2(+)-year-old animals.

  15. Information transfer via implicit encoding with delay time modulation in a time-delay system

    Energy Technology Data Exchange (ETDEWEB)

    Kye, Won-Ho, E-mail: whkye@kipo.go.kr [Korean Intellectual Property Office, Government Complex Daejeon Building 4, 189, Cheongsa-ro, Seo-gu, Daejeon 302-701 (Korea, Republic of)

    2012-08-20

    A new encoding scheme for information transfer with modulated delay time in a time-delay system is proposed. In the scheme, the message is implicitly encoded into the modulated delay time. The information transfer rate as a function of encoding redundancy in various noise scales is presented and it is analyzed that the implicit encoding scheme (IES) has stronger resistance against channel noise than the explicit encoding scheme (EES). In addition, its advantages in terms of secure communication and feasible applications are discussed. -- Highlights: ► We propose new encoding scheme with delay time modulation. ► The message is implicitly encoded with modulated delay time. ► The proposed scheme shows stronger resistance against channel noise.

  16. Linear delay-differential systems with commensurate delays an algebraic approach

    CERN Document Server

    Gluesing-Luerssen, Heide

    2002-01-01

    The book deals with linear time-invariant delay-differential equations with commensurated point delays in a control-theoretic context. The aim is to show that with a suitable algebraic setting a behavioral theory for dynamical systems described by such equations can be developed. The central object is an operator algebra which turns out to be an elementary divisor domain and thus provides the main tool for investigating the corresponding matrix equations. The book also reports the results obtained so far for delay-differential systems with noncommensurate delays. Moreover, whenever possible it points out similarities and differences to the behavioral theory of multidimensional systems, which is based on a great deal of algebraic structure itself. The presentation is introductory and self-contained. It should also be accessible to readers with no background in delay-differential equations or behavioral systems theory. The text should interest researchers and graduate students.

  17. Delay-dependent stability and stabilization criteria of networked control systems with multiple time-delays

    Institute of Scientific and Technical Information of China (English)

    Huaicheng YAN; Xinhan HUANG; Min WANG

    2006-01-01

    This paper deals with the problem of delay-dependent stability and stabilization for networked control systems(NCSs)with multiple time-delays. In view of multi-input and multi-output(MIMO) NCSs with many independent sensors and actuators, a continuous time model with distributed time-delays is proposed. Utilizing the Lyapunov stability theory combined with linear matrix inequalities(LMIs) techniques, some new delay-dependent stability criteria for NCSs in terms of generalized Lyapunov matrix equation and LMIs are derived. Stabilizing controller via state feedback is formulated by solving a set of LMIs. Compared with the reported methods, the proposed methods give a less conservative delay bound and more general results. Numerical example and simulation show that the methods are less conservative and more effective.

  18. Relation between delayed feedback and delay-coupled systems and its application to chaotic lasers

    Energy Technology Data Exchange (ETDEWEB)

    Soriano, Miguel C., E-mail: miguel@ifisc.uib-csic.es; Flunkert, Valentin; Fischer, Ingo [Instituto de Física Interdisciplinar y Sistemas Complejos, IFISC (CSIC-UIB), Campus Universitat Illes Balears, E-07122 Palma de Mallorca (Spain)

    2013-12-15

    We present a systematic approach to identify the similarities and differences between a chaotic system with delayed feedback and two mutually delay-coupled systems. We consider the general case in which the coupled systems are either unsynchronized or in a generally synchronized state, in contrast to the mostly studied case of identical synchronization. We construct a new time-series for each of the two coupling schemes, respectively, and present analytic evidence and numerical confirmation that these two constructed time-series are statistically equivalent. From the construction, it then follows that the distribution of time-series segments that are small compared to the overall delay in the system is independent of the value of the delay and of the coupling scheme. By focusing on numerical simulations of delay-coupled chaotic lasers, we present a practical example of our findings.

  19. Delay-dependent robust stability for neutral systems with mixed discrete-and-neutral delays

    Institute of Scientific and Technical Information of China (English)

    Yong HE; Min WU; Jinhua SHE

    2004-01-01

    This paper focuses on the problem of delay-dependent robust stability of neutral systems with different discrete-and-neutral delays and time-varying structured uncertainties.Some new criteria are presented,in which some free weighting matrices are used to express the relationships between the terms in the Leibniz-Newton formula.The criteria include the information on the size of both neutral-and-discrete delays.It is shown that the present results also include the results for identical discrete-and-neutral delays as special cases.A numerical example illustrates the improvement of the proposed methods over the previous methods and the influences between the discrete and neutral delays.

  20. The Strong Lensing Time Delay Challenge (2014)

    Science.gov (United States)

    Liao, Kai; Dobler, G.; Fassnacht, C. D.; Treu, T.; Marshall, P. J.; Rumbaugh, N.; Linder, E.; Hojjati, A.

    2014-01-01

    Time delays between multiple images in strong lensing systems are a powerful probe of cosmology. At the moment the application of this technique is limited by the number of lensed quasars with measured time delays. However, the number of such systems is expected to increase dramatically in the next few years. Hundred such systems are expected within this decade, while the Large Synoptic Survey Telescope (LSST) is expected to deliver of order 1000 time delays in the 2020 decade. In order to exploit this bounty of lenses we needed to make sure the time delay determination algorithms have sufficiently high precision and accuracy. As a first step to test current algorithms and identify potential areas for improvement we have started a "Time Delay Challenge" (TDC). An "evil" team has created realistic simulated light curves, to be analyzed blindly by "good" teams. The challenge is open to all interested parties. The initial challenge consists of two steps (TDC0 and TDC1). TDC0 consists of a small number of datasets to be used as a training template. The non-mandatory deadline is December 1 2013. The "good" teams that complete TDC0 will be given access to TDC1. TDC1 consists of thousands of lightcurves, a number sufficient to test precision and accuracy at the subpercent level, necessary for time-delay cosmography. The deadline for responding to TDC1 is July 1 2014. Submissions will be analyzed and compared in terms of predefined metrics to establish the goodness-of-fit, efficiency, precision and accuracy of current algorithms. This poster describes the challenge in detail and gives instructions for participation.