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Sample records for operating characteristic analysis

  1. ANALYSIS OF THE OPERATIONAL CHARACTERISTICS OF DIESEL-ELECTRIC LOCOMOTIVES

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    L. V. Ursulyak

    2014-12-01

    Full Text Available Purpose. To compare the operational characteristics of freight diesel-electric locomotives ER20CF and 2М62м, which are operated with Lithuanian Railways. Important problems on traction calculations are considered in this article. In this article the critical tasks of traction calculations are solved. It is the main computational tool in the rational functioning, planning and development of railways: determination of the estimated weight of the rolling stock, the diagrams construction of specific resultant forces of a train, the permitted speed definition of the train on the slopes, curves of train traffic construction on the section. Methodology. Using the rules and methods of traction calculations the analysis of the basic operational characteristics of the modernized freight diesel-electric locomotive 2М62m and freight passenger dual locomotive 2ER20CF was held. The maximum weight of the train set, the track structure on a high-speed ascent through the use of kinetic energy (with traction and without traction, technical speed, acceleration force and the value of the smallest radius curve are selected as controlled parameters. During the calculations it was considered that the trains were formed of a fully loaded four-axle gondola cars, model 112-119 (feature-606 with axle load of 23.5 t; the motion was carried out on the continuous welded rail track; the front of the train set is a dual locomotive 2ER20CF or two locomotive 2М62м. Longitudinal profile of the road on the route Vilnus–KlF was analyzed for the choice of theoretical rise. Inspection concerning the possibility of overcoming the high-speed rise was performed with an analytical method, based on the use of the kinetic energy accumulated by the overcoming of «light» elements of the profile. Findings. In the calculations, the maximum weight of the train set taking into account theoretical rise was analyzed. The inspection of the theoretical weight of the train set on a reliable

  2. Sensitivity to imputation models and assumptions in receiver operating characteristic analysis with incomplete data.

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    Karakaya, Jale; Karabulut, Erdem; Yucel, Recai M

    Modern statistical methods using incomplete data have been increasingly applied in a wide variety of substantive problems. Similarly, receiver operating characteristic (ROC) analysis, a method used in evaluating diagnostic tests or biomarkers in medical research, has also been increasingly popular problem in both its development and application. While missing-data methods have been applied in ROC analysis, the impact of model mis-specification and/or assumptions (e.g. missing at random) underlying the missing data has not been thoroughly studied. In this work, we study the performance of multiple imputation (MI) inference in ROC analysis. Particularly, we investigate parametric and non-parametric techniques for MI inference under common missingness mechanisms. Depending on the coherency of the imputation model with the underlying data generation mechanism, our results show that MI generally leads to well-calibrated inferences under ignorable missingness mechanisms.

  3. A brief history of free-response receiver operating characteristic paradigm data analysis.

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    Chakraborty, Dev P

    2013-07-01

    In the receiver operating characteristic paradigm the observer assigns a single rating to each image and the location of the perceived abnormality, if any, is ignored. In the free-response receiver operating characteristic paradigm the observer is free to mark and rate as many suspicious regions as are considered clinically reportable. Credit for a correct localization is given only if a mark is sufficiently close to an actual lesion; otherwise, the observer's mark is scored as a location-level false positive. Until fairly recently there existed no accepted method for analyzing the resulting relatively unstructured data containing random numbers of mark-rating pairs per image. This report reviews the history of work in this field, which has now spanned more than five decades. It introduces terminology used to describe the paradigm, proposed measures of performance (figures of merit), ways of visualizing the data (operating characteristics), and software for analyzing free-response receiver operating characteristic studies.

  4. [Receiver operating characteristic analysis and the cost--benefit analysis in determination of the optimal cut-off point].

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    Vránová, J; Horák, J; Krátká, K; Hendrichová, M; Kovaírková, K

    2009-01-01

    An overview of the use of Receiver Operating Characteristic (ROC) analysis within medicine is provided. A survey of the theory behind the analysis is offered together with a presentation on how to create a ROC curve and how to use Cost--Benefit analysis to determine the optimal cut-off point or threshold. The use of ROC analysis is exemplified in the "Cost--Benefit analysis" section of the paper. In these examples, it can be seen that the determination of the optimal cut-off point is mainly influenced by the prevalence and the severity of the disease, by the risks and adverse events of treatment or the diagnostic testing, by the overall costs of treating true and false positives (TP and FP), and by the risk of deficient or non-treatment of false negative (FN) cases.

  5. Receiver operating characteristic (ROC) analysis of images reconstructed with iterative expectation maximization algorithms

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    Takahashi, Yasuyuki; Murase, Kenya [Osaka Medical Coll., Takatsuki (Japan). Graduate School; Higashino, Hiroshi; Sogabe, Ichiro; Sakamoto, Kana

    2001-12-01

    The quality of images reconstructed by means of the maximum likelihood-expectation maximization (ML-EM) and ordered subset (OS)-EM algorithms, was examined with parameters such as the number of iterations and subsets, then compared with the quality of images reconstructed by the filtered back projection method. Phantoms showing signals inside signals, which mimicked single-photon emission computed tomography (SPECT) images of cerebral blood flow and myocardial perfusion, and phantoms showing signals around the signals obtained by SPECT of bone and tumor were used for experiments. To determine signals for recognition, SPECT images in which the signals could be appropriately recognized with a combination of fewer iterations and subsets of different sizes and densities were evaluated by receiver operating characteristic (ROC) analysis. The results of ROC analysis were applied to myocardial phantom experiments and scintigraphy of myocardial perfusion. Taking the image processing time into consideration, good SPECT images were obtained by OS-EM at iteration No. 10 and subset 5. This study will be helpful for selection of parameters such as the number of iterations and subsets when using the ML-EM or OS-EM algorithms. (author)

  6. Measuring diagnostic and predictive accuracy in disease management: an introduction to receiver operating characteristic (ROC) analysis.

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    Linden, Ariel

    2006-04-01

    Diagnostic or predictive accuracy concerns are common in all phases of a disease management (DM) programme, and ultimately play an influential role in the assessment of programme effectiveness. Areas, such as the identification of diseased patients, predictive modelling of future health status and costs and risk stratification, are just a few of the domains in which assessment of accuracy is beneficial, if not critical. The most commonly used analytical model for this purpose is the standard 2 x 2 table method in which sensitivity and specificity are calculated. However, there are several limitations to this approach, including the reliance on a single defined criterion or cut-off for determining a true-positive result, use of non-standardized measurement instruments and sensitivity to outcome prevalence. This paper introduces the receiver operator characteristic (ROC) analysis as a more appropriate and useful technique for assessing diagnostic and predictive accuracy in DM. Its advantages include; testing accuracy across the entire range of scores and thereby not requiring a predetermined cut-off point, easily examined visual and statistical comparisons across tests or scores, and independence from outcome prevalence. Therefore the implementation of ROC as an evaluation tool should be strongly considered in the various phases of a DM programme.

  7. Covariate Adjustment in Receiver Operating Characteristic Curve Analysis for PSA in Diagnosis of Prostate Cancer

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    Emre DEMIR

    2016-10-01

    Full Text Available Objective: Markers which are used for classification into two groups, such as patient / healthy, benign/malignant or prediction of optimal cut off value for diagnostic test and evaluating the performance of diagnostic tests is evaluated by Receiver Operating Characteristic (ROC curve in the diagnostic test researches. In classification accuracy research, some variables such as gender and age, commonly is not similar in groups. In these cases, covariates should be considered to estimate in the area under ROC and covariate adjustment for ROC should be performed. This study aims to introduce methods in the literature for the effect of covariate adjustment and to present an application with sample from the health field. Material and Methods: In the study, we introduced methods used in the literatüre for covariate adjustment and prediction of the area under ROC curves as well as an application with data from the field of urology. In this study, 105 PSA (prostate specific antigen measurements were taken in order to examine the covariate effect for the age variable and to assess the diagnostic performance of PSA measurements with regard to pathologic methods. Results: Covariate effect were found statistically significant with 0.733 parameter estimation of the age in ROC curves analysis with PSA data (p<0.001. According to the methods (Non-parametric (empirical, non-parametric (normal, semi-parametric (empirical, parametric (normal that estimates of the area under ROC curves which is obtained without covariate effect were found 0.708, 0.629, 0.709 and 0.628, respectively, by using PSA measurements. Area under the curve that obtained by covariate adjustment were significantly lower as compared to the traditional ROC with estimation 0.580, 0.577, 0.582 and 0.579. Conclusion: Area under the ROC curves should be estimated with adjustment according to the covariates that could affect the markers value of diagnostic tests performed in concert with matching

  8. Assessing the Classification Accuracy of Early Numeracy Curriculum-Based Measures Using Receiver Operating Characteristic Curve Analysis

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    Laracy, Seth D.; Hojnoski, Robin L.; Dever, Bridget V.

    2016-01-01

    Receiver operating characteristic curve (ROC) analysis was used to investigate the ability of early numeracy curriculum-based measures (EN-CBM) administered in preschool to predict performance below the 25th and 40th percentiles on a quantity discrimination measure in kindergarten. Areas under the curve derived from a sample of 279 students ranged…

  9. Analysis of Performance of Jet Engine from Characteristics of Components II : Interaction of Components as Determined from Engine Operation

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    Goldstein, Arthur W; Alpert, Sumner; Beede, William; Kovach, Karl

    1949-01-01

    In order to understand the operation and the interaction of jet-engine components during engine operation and to determine how component characteristics may be used to compute engine performance, a method to analyze and to estimate performance of such engines was devised and applied to the study of the characteristics of a research turbojet engine built for this investigation. An attempt was made to correlate turbine performance obtained from engine experiments with that obtained by the simpler procedure of separately calibrating the turbine with cold air as a driving fluid in order to investigate the applicability of component calibration. The system of analysis was also applied to prediction of the engine and component performance with assumed modifications of the burner and bearing characteristics, to prediction of component and engine operation during engine acceleration, and to estimates of the performance of the engine and the components when the exhaust gas was used to drive a power turbine.

  10. Transmission Technologies and Operational Characteristic Analysis of Hybrid UHV AC/DC Power Grids in China

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    Tian, Zhang; Yanfeng, Gong

    2017-05-01

    In order to solve the contradiction between demand and distribution range of primary energy resource, Ultra High Voltage (UHV) power grids should be developed rapidly to meet development of energy bases and accessing of large-scale renewable energy. This paper reviewed the latest research processes of AC/DC transmission technologies, summarized the characteristics of AC/DC power grids, concluded that China’s power grids certainly enter a new period of large -scale hybrid UHV AC/DC power grids and characteristics of “strong DC and weak AC” becomes increasingly pro minent; possible problems in operation of AC/DC power grids was discussed, and interaction or effect between AC/DC power grids was made an intensive study of; according to above problems in operation of power grids, preliminary scheme is summarized as fo llows: strengthening backbone structures, enhancing AC/DC transmission technologies, promoting protection measures of clean energ y accessing grids, and taking actions to solve stability problems of voltage and frequency etc. It’s valuable for making hybrid UHV AC/DC power grids adapt to operating mode of large power grids, thus guaranteeing security and stability of power system.

  11. Analysis on Biomechanical Characteristics of Post-operational Vertebral C5-C6 Segments

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    Heqiang Tian

    2016-03-01

    Full Text Available Both anterior cervical decompression and fusion (ACDF and artificial cervical disc replacement (ACDR have obvious advantages in the treatment of cervical spondylosis. To analyze the operation results, it is absolutely necessary to study the biomechanics of the movement range of post-operational vertebral C5-C6 segments, especially the biomechanical characteristics in cervical tissues in actual movements. In this study, using the human vertebral 3D graph gained by imaging diagnosis (CT, a vertebral solid model is established by the 3D reconstruction algorithm and reverse engineering technology. After that, with cervical soft tissue structure added to the solid model and set with a joint contact mechanism, a finite element model with a complete, accurate cervical C5-C6 kinematic unit is constructed, based on relevant physiological anatomical knowledge. This model includes vertebral segments, an intervertebral disc, ligament and zygopophysis in the cervical C5-C6 kinematic unit. In the created vertebral finite element model, the model is amended, referring to ACDF and ACDR, and the load and constraint are applied to a normal group, a fusion group and a displacement group, so as to analyze the biomechanical characteristics of the cervical vertebra after ACDF and ACDR. By comparing the finite element simulation results of different surgeries, this paper is intended to evaluate the functions and biomechanical behaviors of the post-operational vertebra, and explore the influence of the operation on the biomechanical stability of the cervical vertebra. This will provide theoretical guidance for implementation and optimization of ACDF and ACDR.

  12. Operational characteristics and analysis of the immersed-Bz diode on RITS-3.

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    Bruner, Nichelle " Nicki" ; Oliver, Bryan Velten; Portillo, Salvador; Puetz, Elizabeth A.; Johnston, Mark D.; Welch, Dale Robert; Rose, David Vincent; Cooper, G.M. (AWE, Aldermaston, Reading, United Kingdom); McLean, John (AWE, Aldermaston, Reading, United Kingdom); Rovang, Dean Curtis; Maenchen, John Eric

    2006-02-01

    The immersed-B{sub z} diode is being developed as a high-brightness, flash x-ray radiography source. This diode is a foil-less electron-beam diode with a long, thin, needle-like cathode inserted into the bore of a solenoid. The solenoidal magnetic field guides the electron beam emitted from the cathode to the anode while maintaining a small beam radius. The electron beam strikes a thin, high-atomic-number anode and produces bremsstrahlung. We report on an extensive series of experiments where an immersed-B{sub z} diode was fielded on the RITS-3 pulsed power accelerator, a 3-cell inductive voltage generator that produced peak voltages between 4 and 5 MV, {approx}140 kA of total current, and power pulse widths of {approx}50 ns. The diode is a high impedance device that, for these parameters, nominally conducts {approx}30 kA of electron beam current. Diode operating characteristics are presented and two broadly characterized operating regimes are identified: a nominal operating regime where the total diode current is characterized as classically bipolar and an anomalous impedance collapse regime where the total diode current is in excess of the bipolar limit and up to the full accelerator current. The operating regimes are approximately separated by cathode diameters greater than {approx}3 mm for the nominal regime and less than {approx} 3 mm for the anomalous impedance collapse regime. This report represents a compilation of data taken on RITS-3. Results from key parameter variations are presented in the main body of the report and include cathode diameter, anode-cathode gap, and anode material. Results from supporting parameter variations are presented in the appendices and include magnetic field strength, prepulse, pressure and accelerator variations.

  13. Characteristic analysis of a water hydraulic pilot-operated pressure-reducing valve

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    Mao, Xuyao; Hu, Junhua; Wu, Chao; Liu, Yiou; Liu, Yinshui

    2017-06-01

    Comprehensive characteristics of a seawater hydraulic pilot-operated pressure-reducing valve with constant pressure output were analyzed. A rated pressure of 15MPa and a rated flowrate of 40L/min were offered in the numerical work. Static and dynamic analyses show good behaviors: The settling time is less than 0.2s, the output pressure variation is about 0.3MPa at the maximum when input pressure or flowrate is flucturing, and the steady external leakage is below 0.025L/min. The pilot spring regulates the output pressure and the main spring has an ability to adjust the output pressure variation faintly. The narrow hole diameter of the adjustable damping plugs is negatively related to the respond time. And appropriately raising the spring chamber volume can evidently reduce outlet pressure impact of the valve when input mutations happen.

  14. System Modeling and Operational Characteristic Analysis for an Orbital Friction Vibration Actuator Used in Orbital Vibration Welding

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    XU, F.

    2013-05-01

    Full Text Available Orbital Friction Vibration Actuator (OFVA is a core component of Orbital Friction Welding (OFW, which is a novel apertureless welding technology utilizing friction heat to implement solid-state joining. In this paper, topology and operational principle of OFVA are introduced, the analytical formulas of the electromagnetic force for the x and y directions, which can drive the mover to generate a circular motion trajectory, are derived, and the characteristic of static electromagnetic force is predicted by analytical method and 2-D (two-dimensional FEM (finite element method, 3-D and measurement. The coupled magnetic field-circuit-motion simulation models which are driven by current and voltage source are established, respectively, and some of its operational characteristics are analyzed. Simulation and experiment validate theoretical analysis and the feasibility of the fabricated prototype, demonstrate the good performance of the OFVA, and provide valuable reference for engineering applications.

  15. Experimental Design and Data Analysis in Receiver Operating Characteristic Studies: Lessons Learned from Reports in Radiology from 1997 to 20061

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    Shiraishi, Junji; Pesce, Lorenzo L.; Metz, Charles E.; Doi, Kunio

    2009-01-01

    Purpose: To provide a broad perspective concerning the recent use of receiver operating characteristic (ROC) analysis in medical imaging by reviewing ROC studies published in Radiology between 1997 and 2006 for experimental design, imaging modality, medical condition, and ROC paradigm. Materials and Methods: Two hundred ninety-five studies were obtained by conducting a literature search with PubMed with two criteria: publication in Radiology between 1997 and 2006 and occurrence of the phrase “receiver operating characteristic.” Studies returned by the query that were not diagnostic imaging procedure performance evaluations were excluded. Characteristics of the remaining studies were tabulated. Results: Two hundred thirty-three (79.0%) of the 295 studies reported findings based on observers' diagnostic judgments or objective measurements. Forty-three (14.6%) did not include human observers, with most of these reporting an evaluation of a computer-aided diagnosis system or functional data obtained with computed tomography (CT) or magnetic resonance (MR) imaging. The remaining 19 (6.4%) studies were classified as reviews or meta-analyses and were excluded from our subsequent analysis. Among the various imaging modalities, MR imaging (46.0%) and CT (25.7%) were investigated most frequently. Approximately 60% (144 of 233) of ROC studies with human observers published in Radiology included three or fewer observers. Conclusion: ROC analysis is widely used in radiologic research, confirming its fundamental role in assessing diagnostic performance. However, the ROC studies reported in Radiology were not always adequate to support clear and clinically relevant conclusions. © RSNA, 2009 Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.2533081632/-/DC1 PMID:19864510

  16. Protective clothing for pesticide operators: part II--data analysis of fabric characteristics.

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    Shaw, Anugrah; Schiffelbein, Paul

    2016-01-01

    Development of objective measurements is an important requirement for establishing performance-based standards for protective clothing used while handling pesticide. This study, the second in a two-part series, reports on the work completed to evaluate the performance of approximately 100 fabrics that are either used or have the potential to be used for garments worn by operators while applying pesticides. Part I, published separately, provides an overview of these issues and describes research undertaken to select a test chemical for use in subsequent studies. The goals of this study were first to develop a comprehensive approach to evaluate the performance of garments currently being used by pesticide operators, and second, to use the laboratory and field data in the development of performance specifications.

  17. Parallel Operation Characteristics Analysis of Sewage Source Heat Pump Units in Winter

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    庄兆意; 张承虎; 王海燕; 孙德兴

    2010-01-01

    Sewage source heat pump unit operates under partial load most of the time, and study on the law of coefficient of performance (COP) of the unit varying with load ratio can provide basis for the heat pump units running in high efficiency. A mathematical model determining COP, evaporation temperature and condensation temperature of a single unit was proposed. Under the condition of uniform load distribution, the model was established according to different ways of bearing partial load with the same type multi...

  18. Receiver-Operating-Characteristic Analysis Reveals Superiority of Scale-Dependent Wavelet and Spectral Measures for Assessing Cardiac Dysfunction

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    Thurner, S; Lowen, S B; Teich, M C; Thurner, Stefan; Feurstein, Markus C.; Lowen, Steven B.; Teich, Malvin C.

    1998-01-01

    Receiver-operating-characteristic (ROC) analysis was used to assess the suitability of various heart rate variability (HRV) measures for correctly classifying electrocardiogram records of varying lengths as normal or revealing the presence of heart failure. Scale-dependent HRV measures were found to be substantially superior to scale-independent measures (scaling exponents) for discriminating the two classes of data over a broad range of record lengths. The wavelet-coefficient standard deviation at a scale near 32 heartbeat intervals, and its spectral counterpart near 1/32 cycles per interval, provide reliable results using record lengths just minutes long. A jittered integrate-and-fire model built around a fractal Gaussian-noise kernel provides a realistic, though not perfect, simulation of heartbeat sequences.

  19. Diagnostic accuracy of serum biochemical fibrosis markers in children with chronic hepatitis B evaluated by receiver operating characteristics analysis.

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    Lebensztejn, Dariusz Marek; Skiba, Elzbieta; Tobolczyk, Jolanta; Sobaniec-Lotowska, Maria Elzbieta; Kaczmarski, Maciej

    2005-12-07

    To investigate the diagnostic accuracy of potent serum biochemical fibrosis markers in children with chronic hepatitis B evaluated by receiver operating characteristics (ROC) analysis. We determined the serum level of apolipoprotein A-I (APO A-I), haptoglobin (HPT) and a-2 macroglobulin (A2M) with an automatic nephelometer in 63 children (age range 4-17 years, mean 10 years) with biopsy-verified chronic HBeAg-positive hepatitis B. Fibrosis stage and inflammation grade were assessed in a blinded fashion according to Batts and Ludwig. We defined mild liver fibrosis as a score < or =2 and advanced fibrosis as a score equal to 3. ROC analysis was used to calculate the power of the assays to detect advanced liver fibrosis (AccuROC, Canada). Serum concentrations of APO A-I, HPT and A2M were not significantly different in patients with chronic hepatitis B compared to controls. However, APO A-I level of 1.19 ng/L had a sensitivity of 85.7% and a specificity of 60.7% (AUC = 0.7117, P = 0.035) to predict advanced fibrosis. All other serum biochemical markers and their combination did not allow a useful prediction. None of these markers was a good predictor of histologic inflammation. Apolipoprotein A-I may be a suitable serum marker to predict advanced liver fibrosis in children with chronic hepatitis B.

  20. Diagnostic accuracy of serum biochemical fibrosis markers in children with chronic hepatitis B evaluated by receiver operating characteristics analysis

    Institute of Scientific and Technical Information of China (English)

    Dariusz Marek Lebensztejn; El(z)bieta Skiba; Jolanta Tobolczyk; Maria El(z)bieta Sobaniec-Lotowska; Maciej Kaczmarski

    2005-01-01

    AIM: To investigate the diagnostic accuracy of potent serum biochemical fibrosis markers in children with chronic hepatitis B evaluated by receiver operating characteristics (ROC) analysis.METHODS: We determined the serum level of apolipoprotein A-I (APO A-I), haptoglobin (HPT) and a-2macroglobulin (A2M) with an automatic nephelometer in 63 children (age range 4-17 years, mean 10 years)with biopsy-verified chronic HBeAg-positive hepatitis B.Fibrosis stage and inflammation grade were assessed in a blinded fashion according to Batts and Ludwig. We defined mild liver fibrosis as a score ≤2 and advanced fibrosis as a score equal to 3. ROC analysis was used to calculate the power of the assays to detect advanced liver fibrosis (AccuROC, Canada).RESULTS: Serum concentrations of APO A-I, HPT and A2M were not significantly different in patients with chronic hepatitis B compared to controls. However, APO A-I level of 1.19 ng/L had a sensitivity of 85.7% and a specificity of 60.7% (AUC = 0.7117, P = 0.035) to predict advanced fibrosis. All other serum biochemical markers and their combination did not allow a useful prediction.None of these markers was a good predictor of histologic inflammation.CONCLUSION: Apolipoprotein A-I may be a suitable serum marker to predict advanced liver fibrosis in children with chronic hepatitis B.

  1. Operational characteristics analysis of a 8 mH class HTS DC reactor for an LCC type HVDC system

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    Kim, S. K.; Go, B. S.; Dinh, M. C.; Park, M.; Yu, I. K. [Changwon National University, Changwon (Korea, Republic of); Kim, J. H. [Daejeon University, Daejeon (Korea, Republic of)

    2015-03-15

    Many kinds of high temperature superconducting (HTS) devices are being developed due to its several advantages. In particular, the advantages of HTS devices are maximized under the DC condition. A line commutated converter (LCC) type high voltage direct current (HVDC) transmission system requires large capacity of DC reactors to protect the converters from faults. However, conventional DC reactor made of copper causes a lot of electrical losses. Thus, it is being attempted to apply the HTS DC reactor to an HVDC transmission system. The authors have developed a 8 mH class HTS DC reactor and a model-sized LCC type HVDC system. The HTS DC reactor was operated to analyze its operational characteristics in connection with the HVDC system. The voltage at both ends of the HTS DC reactor was measured to investigate the stability of the reactor. The voltages and currents at the AC and DC side of the system were measured to confirm the influence of the HTS DC reactor on the system. Two 5 mH copper DC reactors were connected to the HVDC system and investigated to compare the operational characteristics. In this paper, the operational characteristics of the HVDC system with the HTS DC reactor according to firing angle are described. The voltage and current characteristics of the system according to the types of DC reactors and harmonic characteristics are analyzed. Through the results, the applicability of an HTS DC reactor in an HVDC system is confirmed.

  2. Summary receiver operating characteristics (SROC) and hierarchical SROC models for analysis of diagnostic test evaluations of antibody ELISAs for paratuberculosis.

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    Toft, Nils; Nielsen, Søren S

    2009-11-15

    Critical, systematic reviews of available diagnostic test evaluations are a meticulous approach to synthesize evidence about a diagnostic test. However, often the review finds that data quality is poor due to deficiencies in design and reporting of the test evaluations and formal statistical comparisons are discouraged. Even when only simple summary measures are appropriate, the strong correlation between sensitivity and specificity and their dependence on differences in diagnostic threshold across studies, creates the need for tools to summarise properties of the diagnostic test under investigation. This study presents summary receiver operating characteristics (SROC) analysis as a means to synthesize information from diagnostic test evaluation studies. Using data from a review of diagnostic tests for ante mortem diagnosis of paratuberculosis as an illustration, SROC and hierarchical SROC (HSROC) analysis were used to estimate overall diagnostic accuracies of antibody ELISAs for bovine paratuberculosis while accounting for covariates: the target condition (infectious or infected) used in the test evaluation (one for the evaluation of Se and one for Sp); and the type of test (serum vs. milk). The methods gave comparable results (regarding the estimated diagnostic log odds ratio), considering the small sample size and the quality of data. The SROC analysis found a difference in the performance of tests when the target condition for evaluation of Se was infected rather than infectious, suggesting that ELISAs are not suitable for detecting infected cattle. However, the SROC model does not take differences in sample size between study units into account, whereas the HSROC allows for both between and within study variation. Considering the small sample size, more credibility should be given to the results of the HSROC. For both methods the area under the (H)SROC curve was calculated and results were comparable. The conclusion is that while the SROC is simpler and easier

  3. Some characteristics of offshore operations

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    Popov Đorđe

    2011-01-01

    Full Text Available Offshore operations are not on the margins of the world economy. They are an integral part of modern business practice. They have become one of the most important instruments in the contemporary globalized financial system. Offshore operations and tax havens are not only conduits for tax avoidance and evasion but belong more broadly to the world of finance, for the business of managing the monetary resources of an organization, country or individuals. Offshore business operating in tax havens is at the heart of a particular type of globalization that is characterized by a growing gap between the very rich and everyone else. Tax havens are financial conduits that, in exchange for a fee, use their one principal asset- their sovereignty to serve a nonresident constituency of accountants and lawyers, bankers and financiers, who bring a demand for offshore operations.

  4. Composition and Characteristics of Moduli for Automatic Analysis of Failures in Operation of Boiling and Turbine Equipment at Thermal Power Station

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    V. A. Yanitsky

    2006-01-01

    Full Text Available The paper presents composition and brief characteristics of diagnostic moduli applied in an automatic system for detection and analysis of failures iii operation of boiling and turbine equipment at thermal power stations. Realization of automatic analysis in respect of technological situations makes it possible to form messages for duty personnel. These messages contain data which is considered as an important one at the actual moment and the messages have such form that ensures the most favourable conditions in order to take a decision pertaining to on-line control of the equipment operation.

  5. Numerical analysis of flow features and operation characteristics of a rocket-based combined-cycle inlet in ejector mode

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    Shi, Lei; Liu, Xiaowei; He, Guoqiang; Qin, Fei; Wei, Xianggeng; Yang, Bin; Liu, Jie

    2016-10-01

    A ready-made central strut-based rocket-based combined-cycle (RBCC) engine was numerically investigated in the ejector mode. The flow features in the RBCC inlet and the matching characteristics between the inlet and the embedded rocket during different flight regimes were examined in detail. It was necessary to perform integrated numerical simulations in the ejector mode within considerable pressure far fields around the inlet/exhaust system. The observed flow features and operation characteristics in the RBCC inlet were strongly correlated with the flight conditions, inlet configuration, and operation of the embedded rocket. It was further found that the integrated function status of multiple factors significantly influenced the performance of the RBCC engine in the ejector mode. The two parameters that macroscopically affected the performance most were the air entrainment mass and the drag of the RBCC inlet. To improve these parameters, it is vital to employ an appropriate design of the RBCC inlet and establish the optimal flight trajectory of the flight vehicle.

  6. 49 CFR 236.717 - Characteristics, operating.

    Science.gov (United States)

    2010-10-01

    ..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.717 Characteristics, operating. The measure of electrical values at which electrical or...

  7. Operational Modal Analysis Tutorial

    DEFF Research Database (Denmark)

    Brincker, Rune; Andersen, Palle

    analysis in an easier way and in many cases more effectively than traditional modal analysis methods. It can be applied for modal testing and analysis on a wide range of structures and not only for problems generally investigated using traditional modal analysis, but also for those requiring load......In this paper the basic principles in operational modal testing and analysis are presented and discussed. A brief review of the techniques for operational modal testing and identification is presented, and it is argued, that there is now a wide range of techniques for effective identification...... estimation, vibration level estimation and fatigue analysis....

  8. On some numerical characteristics of operators

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    M. Gürdal

    2015-01-01

    Full Text Available We investigate some numerical characteristics of Toeplitz operators including the numerical range, maximal numerical range and maximal Berezin set. Further, we establish an inequality for the Berezin number of an arbitrary operator on the Hardy–Hilbert space of the unit disc.

  9. Operational Modal Analysis Tutorial

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    Brincker, Rune; Andersen, Palle

    2007-01-01

    In this paper the basic principles in operational modal testing and analysis are presented and discussed. A brief review of the techniques for operational modal testing and identification is presented, and it is argued, that there is now a wide range of techniques for effective identification of modal parameters of practical interest - including the mode shape scaling factor - with a high degree of accuracy. It is also argued that the operational technology offers the user a number of advanta...

  10. Evaluation of hemoglobin performance in the assessment of iron stores in feto-maternal pairs in a high-risk population: receiver operating characteristic curve analysis

    Directory of Open Access Journals (Sweden)

    José Carlos Jaime-Pérez

    2015-06-01

    Full Text Available Objective: By applying receiver operating characteristic curve analysis, the objective of this study was to see whether hemoglobin levels reflect body iron stores in a group of pregnant women at term who, by using serum ferritin as the reference test, had a high pre-test prob- ability of having iron deficiency anemia. Likewise, we evaluated the ability of hemoglobin and maternal serum ferritin levels to predict iron deficiency anemia in newborns. Methods: Hemoglobin and serum ferritin were measured in 187 pregnant women at term belonging to a group with a high pre-test probability of iron deficiency anemia and their newborns. Women with Hb <11.0 g/dL and newborns with cord Hb <13.0 g/dL were classified as anemic. A serum ferritin <12.0 µg/L in women and a cord blood serum ferritin <35.0 µg/L were considered to reflect empty iron stores. Receiver operating characteristic curve analysis was applied to select the cut-off points that better reflected iron stores. Results: The Hb cut-off point selected by receiver operating characteristic curve analysis in women was <11.5 g/dL (sensitivity: 60.82, specificity: 53.33%, Youden Index: 0.450. Most of the newborns had normal Hb which precluded this analysis. Maternal Hb <11.0 g/dL was the cut-off point that best reflected iron deficiency anemia in newborns (sensitivity: 55.88%, specificity: 57.24%, Youden Index: 0.217. The best cut-off point of maternal serum ferritin to reflect empty iron stores in newborns was <6.0 µg/L (sensitivity: 76.47%, specificity: 31.58%, Youden Index: 0.200. Conclusion: Hemoglobin concentration performed poorly to detect iron deficiency anemia in women at term with high risk for iron deficiency and their newborns.

  11. Evaluation of hemoglobin performance in the assessment of iron stores in feto-maternal pairs in a high-risk population: receiver operating characteristic curve analysis

    Science.gov (United States)

    Jaime-Pérez, José Carlos; García-Arellano, Gisela; Méndez-Ramírez, Nereida; González-Llano, Óscar; Gómez-Almaguer, David

    2015-01-01

    Objective By applying receiver operating characteristic curve analysis, the objective of this study was to see whether hemoglobin levels reflect body iron stores in a group of pregnant women at term who, by using serum ferritin as the reference test, had a high pre-test probability of having iron deficiency anemia. Likewise, we evaluated the ability of hemoglobin and maternal serum ferritin levels to predict iron deficiency anemia in newborns. Methods Hemoglobin and serum ferritin were measured in 187 pregnant women at term belonging to a group with a high pre-test probability of iron deficiency anemia and their newborns. Women with Hb <11.0 g/dL and newborns with cord Hb <13.0 g/dL were classified as anemic. A serum ferritin <12.0 μg/L in women and a cord blood serum ferritin <35.0 μg/L were considered to reflect empty iron stores. Receiver operating characteristic curve analysis was applied to select the cut-off points that better reflected iron stores. Results The Hb cut-off point selected by receiver operating characteristic curve analysis in women was <11.5 g/dL (sensitivity: 60.82, specificity: 53.33%, Youden Index: 0.450). Most of the newborns had normal Hb which precluded this analysis. Maternal Hb <11.0 g/dL was the cut-off point that best reflected iron deficiency anemia in newborns (sensitivity: 55.88%, specificity: 57.24%, Youden Index: 0.217). The best cut-off point of maternal serum ferritin to reflect empty iron stores in newborns was <6.0 μg/L (sensitivity: 76.47%, specificity: 31.58%, Youden Index: 0.200). Conclusion Hemoglobin concentration performed poorly to detect iron deficiency anemia in women at term with high risk for iron deficiency and their newborns. PMID:26041420

  12. A systematic review and meta-analysis of studies evaluating the performance and operational characteristics of dual point-of-care tests for HIV and syphilis.

    Science.gov (United States)

    Gliddon, Harriet D; Peeling, Rosanna W; Kamb, Mary L; Toskin, Igor; Wi, Teodora E; Taylor, Melanie M

    2017-07-26

    Mother-to-child transmission (MTCT) of syphilis and HIV continue to be important yet preventable causes of perinatal and infant morbidity and mortality. To systematically review, critically appraise and perform a meta-analysis to evaluate the operational characteristics of dual rapid diagnostic tests (RDTs) for HIV/syphilis and evaluate whether they are cost effective, acceptable and easy to use. Systematic review and meta-analysis. We searched seven electronic bibliographic databases from 2012 to December 2016 with no language restrictions. Search keywords included HIV, syphilis and diagnosis. We included studies that evaluated the operational characteristics of dual HIV/syphilis RDTs. Outcomes included diagnostic test accuracy, cost effectiveness, ease of use and interpretation and acceptability. All studies were assessed against quality criteria and assessed for risk of bias. Of 1914 identified papers, 18 were included for the meta-analysis of diagnostic accuracy for HIV and syphilis. All diagnostic accuracy evaluation studies showed a very high sensitivity and specificity for HIV and a lower, yet adequate, sensitivity and specificity for syphilis, with some variation among types of test. Dual screening for HIV and syphilis was more cost effective than single rapid tests for HIV and syphilis and prevented more adverse pregnancy outcomes. Qualitative data suggested dual RDTs were highly acceptable to clients, who cited time to result, cost and the requirement of a single finger prick as important characteristics of dual RDTs. The results of this systematic review and meta-analysis can be used by policy-makers and national programme managers who are considering implementing dual RDTs for HIV and syphilis. PROSPERO 2016:CRD42016049168. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  13. Load Characteristics Analysis of State Grid

    Institute of Scientific and Technical Information of China (English)

    Chen Wei; Zhou Feng; Han Xinyang; Shan Baoguo; Zhu Li

    2009-01-01

    @@ Introduction Analysis and forecast of load characteristics are important aspects in power market analysis and prediction.Correctly mastering grid load characteristics and its development trend is not only the vital basis for power planning,generation and operation,but also the important references for formulating the relevant policies.It is usually very hard to grasp the load characteristics of power grid.

  14. Assessing the predictive performance of risk-based water quality criteria using decision error estimates from receiver operating characteristics (ROC) analysis.

    Science.gov (United States)

    McLaughlin, Douglas B

    2012-10-01

    Field data relating aquatic ecosystem responses with water quality constituents that are potential ecosystem stressors are being used increasingly in the United States in the derivation of water quality criteria to protect aquatic life. In light of this trend, there is a need for transparent quantitative methods to assess the performance of models that predict ecological conditions using a stressor-response relationship, a response variable threshold, and a stressor variable criterion. Analysis of receiver operating characteristics (ROC analysis) has a considerable history of successful use in medical diagnostic, industrial, and other fields for similarly structured decision problems, but its use for informing water quality management decisions involving risk-based environmental criteria is less common. In this article, ROC analysis is used to evaluate predictions of ecological response variable status for 3 water quality stressor-response data sets. Information on error rates is emphasized due in part to their common use in environmental studies to describe uncertainty. One data set is comprised of simulated data, and 2 involve field measurements described previously in the literature. These data sets are also analyzed using linear regression and conditional probability analysis for comparison. Results indicate that of the methods studied, ROC analysis provides the most comprehensive characterization of prediction error rates including false positive, false negative, positive predictive, and negative predictive errors. This information may be used along with other data analysis procedures to set quality objectives for and assess the predictive performance of risk-based criteria to support water quality management decisions.

  15. On scaling performance operating characteristics - Caveat emptor

    Science.gov (United States)

    Kantowitz, B. H.; Weldon, M.

    1985-01-01

    Problems associated with scaling and normalizing empirical performance operating characteristics (POCs) are examined. Normalization methods proposed by Wickens (1980) and by Mountford and North (1980) are critically evaluated. Computer simulations are used to generate raw-score and normalized POCs. The interpretation of transformed empirical POCs (Wickens, Mountford, and Schreiner, 1981) is shown to contain inconsistencies. The normalization techniques reviewed fail to resolve POC scaling problems. Caution must be exercised when interpreting transformed POCs.

  16. Operational Characteristics of an Accelerator Driven Fissile Solution System

    Energy Technology Data Exchange (ETDEWEB)

    Kimpland, Robert Herbert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-11-28

    Operational characteristics represent the set of responses that a nuclear system exhibits during normal operation. Operators rely on this behavior to assess the status of the system and to predict the consequences of off-normal events. These characteristics largely refer to the relationship between power and system operating conditions. The static and dynamic behavior of a chain-reacting system, operating at sufficient power, is primarily governed by reactivity effects. The science of reactor physics has identified and evaluated a number of such effects, including Doppler broadening and shifts in the thermal neutron spectrum. Often these reactivity effects are quantified in the form of feedback coefficients that serve as coupling coefficients relating the neutron population and the physical mechanisms that drive reactivity effects, such as fissile material temperature and density changes. The operational characteristics of such nuclear systems usually manifest themselves when perturbations between system power (neutron population) and system operating conditions arise. Successful operation of such systems require the establishment of steady equilibrium conditions. However, prior to obtaining the desired equilibrium (steady-state) conditions, an approach from zero-power (startup) must occur. This operational regime may possess certain limiting system conditions that must be maintained to achieve effective startup. Once steady-state is achieved, a key characteristic of this operational regime is the level of stability that the system possesses. Finally, a third operational regime, shutdown, may also possess limiting conditions of operation that must be maintained. This report documents the operational characteristics of a “generic” Accelerator Driven Fissile Solution (ADFS) system during the various operational regimes of startup, steady-state operation, and shutdown. Typical time-dependent behavior for each operational regime will be illustrated, and key system

  17. The Nevada railroad system: Physical, operational, and accident characteristics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-09-01

    This report provides a description of the operational and physical characteristics of the Nevada railroad system. To understand the dynamics of the rail system, one must consider the system`s physical characteristics, routing, uses, interactions with other systems, and unique operational characteristics, if any. This report is presented in two parts. The first part is a narrative description of all mainlines and major branchlines of the Nevada railroad system. Each Nevada rail route is described, including the route`s physical characteristics, traffic type and volume, track conditions, and history. The second part of this study provides a more detailed analysis of Nevada railroad accident characteristics than was presented in the Preliminary Nevada Transportation Accident Characterization Study (DOE, 1990).

  18. Usefulness of pinhole collimator in differential diagnosis of metastatic disease and degenerative joint disease in the vertebrae; Evaluation by receiver operating characteristics (ROC) analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kosuda, Shigeru; Kawahara, Syunji; Ishibashi, Akihiko; Tamura, Kohei; Tsukatani, Yasushi; Fujii, Hiroshi (Okura National Hospital, Tokyo (Japan)); Kubo, Atsushi; Hashimoto, Shozo

    1989-11-01

    In order to evaluate the diagnostic efficacy of pinhole collimator (PHC) imaging combined with an X-ray for vertebral metastasis, our prospective study has employed receiver operating characteristics (ROC) analysis in 21 patients, 11 with osseous metastasis and 15 with degenerative joint disease in the lumbar vertebrae. PHC imaging provided better anatomic information on the extent of {sup 99m}Tc-MDP accumulation. PHC vertebral scintigraphy had a considerable impact on the decision-making process, although with variations and not very satisfactory results among the physicians with little experience. Our study suggests that PHC imaging and X-ray film are useful in differentiating between osseous metastasis and degenerative joint disease in the vertebra. (author).

  19. Diagnostic Accuracy of Computer based Tests for Attention-Deficit Hyperactivity Disorder: A Receiver-Operating Characteristic Analysis

    Directory of Open Access Journals (Sweden)

    Thomas Dreisörner

    2011-05-01

    Full Text Available Objectives: Attention-Deficit Hyperactivity Disorder (ADHD is one of the most common neurobehavioral diagnosis affecting children today. Guidelines of child psychiatry encourage clinicians to employ clinical interviews and questionnaires, learning and performance tests and behavior observation in making the diagnosis. Special attention tests can be conducted additionally. Computer-based attention tests constitute a promising method to do so as they appeal to children. In clinical practise in Germany two test batteries are commonly used: “Testbatterie zur Aufmerksamkeitsprüfung” (TAP and “Testbatterie zur Aufmerksamkeitsprüfung für Kinder” (KITAP. The latter having been adapted to the motivational needs of children. This study aims at examining the diagnostic accuracy of the TAP and KITAP. Methods: ROC-analysis of TAP- and KITAP parameters and logistic regressions were conducted in a sample of 24 children with and without ADHD. Results: Both TAP and KITAP proved to differentiate between children with and without ADHD. TAP parameters possessed a higher discriminating power for ADHD. In logistic regression analysis TAP parameters led to an amount of variance of 32.5% (KITAP: 21.6% and correct classification rate of 75% (KITAP: 72.9%. Adding KITAP parameters did not improve the amount of variance significantly whereas adding TAP parameters to the KITAP data did result in a significant increase. Conclusion: These findings suggest that TAP and KITAP could serve as useful additional test instruments to help identify cases likely to meet criteria for ADHD in clinical settings. For individual diagnosis TAP and KITAP lack cut-off criteria and substantial classification rates.

  20. A receiver operating characteristic analysis approach for the assessment of the separation of female Mediterranean fruit fly (Diptera: Tephritidae) oviposition distributions.

    Science.gov (United States)

    Alonzo, Todd A; Nakas, Christos T; Papadopoulos, Nikos T; Papachristos, Dimitrios P

    2009-10-01

    Average fecundity rates and survival are the main components of fitness estimates in studies comparing performance of insect populations. Reproduction is inherently age related in most insect species, and age-specific offspring production is very important in determining fitness components. However, comparison of age-specific reproduction rates are not straight forward and most studies limit analyses to comparisons of average fecundity rates and survival as the main components of the performance of insect populations. We develop a receiver operating characteristic (ROC) curve approach to compare lifetime oviposition distributions. We use empirical data of a study of Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) populations, where each fly's lifetime oviposition distribution was recorded for samples studied in natural and artificial oviposition substrates. Currently, there exists no routinely used methodology for the comparison of oviposition distributions and assessment of their separation. ROC analysis is regularly used in two-sample problems in medical biostatistics when the main task is depiction and quantification of the separation of the empirical distributions from which the data arise. Adaptation of such an analysis to our data has shown that age-specific egg-laying distributions can differ, whereas average fecundity rates do not. Therefore, ROC analysis provides a method of gaining insight in the biological process of egg-laying patterns in relatively long-lived insects with many practical and theoretical implications in entomological experimentation.

  1. 14 CFR 23.939 - Powerplant operating characteristics.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Powerplant operating characteristics. 23... General § 23.939 Powerplant operating characteristics. (a) Turbine engine powerplant operating characteristics must be investigated in flight to determine that no adverse characteristics (such as stall,...

  2. Operation characteristics of a multiple type MCFC

    Energy Technology Data Exchange (ETDEWEB)

    Kuroe, S.; Kamo, T. [Hitachi Research Lab., Hitachi, Ltd., Ibaraki-ken (Japan); Fujimura, H.; Kahara, T. [Hitachi, Ltd., Ibaraki-ken (Japan)

    1996-12-31

    Multiple type structure of MCFC of which the separator of the cell is divided by four element cells has been studied. For the stable operation of this type cell, the effect of gas flow rate and temperature distribution on the cell voltage should be clear. In order to clarify these characteristics, a small sized mimic model has been made and tested. The flow rate distribution for the four element cells were varied and cell voltage and temperature distribution were measured for each cell. The decrease in cell voltage and the increase in maximum temperature became remarkable when the apparent utilization factor for one element cell became over 100%. The calculated results agreed fairly good with test results.

  3. Summary receiver operating characteristic curves as a technique for meta-analysis of the diagnostic performance of duplex ultrasonography in peripheral arterial disease

    NARCIS (Netherlands)

    deVries, SO; Hunink, MGM; Polak, JF

    1996-01-01

    Rationale and Objectives. We summarized and compared the diagnostic performance of duplex and color-guided duplex ultrasonography in the evaluation of peripheral arterial disease. We present our research as an example of the use of summary receiver operating characteristic (ROC) curves in a meta-ana

  4. Delineating a Retesting Zone Using Receiver Operating Characteristic Analysis on Serial QuantiFERON Tuberculosis Test Results in US Healthcare Workers

    Directory of Open Access Journals (Sweden)

    Wendy Thanassi

    2012-01-01

    Full Text Available Objective. To find a statistically significant separation point for the QuantiFERON Gold In-Tube (QFT interferon gamma release assay that could define an optimal “retesting zone” for use in serially tested low-risk populations who have test “reversions” from initially positive to subsequently negative results. Method. Using receiver operating characteristic analysis (ROC to analyze retrospective data collected from 3 major hospitals, we searched for predictors of reversion until statistically significant separation points were revealed. A confirmatory regression analysis was performed on an additional sample. Results. In 575 initially positive US healthcare workers (HCWs, 300 (52.2% had reversions, while 275 (47.8% had two sequential positive tests. The most statistically significant (Kappa = 0.48, chi-square = 131.0, P<0.001 separation point identified by the ROC for predicting reversion was the tuberculosis antigen minus-nil (TBag-nil value at 1.11 International Units per milliliter (IU/mL. The second separation point was found at TBag-nil at 0.72 IU/mL (Kappa = 0.16, chi-square = 8.2, P<0.01. The model was validated by the regression analysis of 287 HCWs. Conclusion. Reversion likelihood increases as the TBag-nil approaches the manufacturer's cut-point of 0.35 IU/mL. The most statistically significant separation point between those who test repeatedly positive and those who revert is 1.11 IU/mL. Clinicians should retest low-risk individuals with initial QFT results < 1.11 IU/mL.

  5. [Comparison of LCD and CRT monitors for detection of pulmonary nodules and interstitial lung diseases on digital chest radiographs by using receiver operating characteristic analysis].

    Science.gov (United States)

    Ikeda, Ryuji; Katsuragawa, Shigehiko; Shimonobou, Toshiaki; Hiai, Yasuhiro; Hashida, Masahiro; Awai, Kazuo; Yamashita, Yasuyuki; Doi, Kunio

    2006-05-20

    Soft copy reading of digital images has been practiced commonly in the PACS environment. In this study, we compared liquid-crystal display (LCD) and cathode-ray tube (CRT) monitors for detection of pulmonary nodules and interstitial lung diseases on digital chest radiographs by using receiver operating characteristic (ROC) analysis. Digital chest images with a 1000x1000 matrix size and a 8 bit grayscale were displayed on LCD/CRT monitor with 2M pixels in each observer test. Eight and ten radiologists participated in the observer tests for detection of nodules and interstitial diseases, respectively. In each observer test, radiologists marked their confidence levels for diagnosis of pulmonary nodules or interstitial diseases. The detection performance of radiologists was evaluated by ROC analyses. The average Az values (area under the ROC curve) in detecting pulmonary nodules with LCD and CRT monitors were 0.792 and 0.814, respectively. In addition, the average Az values in detecting interstitial diseases with LCD and CRT monitors were 0.951 and 0.953, respectively. There was no statistically significant difference between LCD and CRT for both detection of pulmonary nodules (P=0.522) and interstitial lung diseases (P=0.869). Therefore, we believe that the LCD monitor instead of the CRT monitor can be used for the diagnosis of pulmonary nodules and interstitial lung diseases in digital chest images.

  6. Regression Analysis on Operating Characteristics of Nanofiltration Membrane Elements%纳滤膜元件运行特性的回归分析

    Institute of Scientific and Technical Information of China (English)

    翟燕; 靖大为; 杨宇星

    2012-01-01

    An exponential function polynomial to characterize operating characteristics of a series of salt rejection rates of nanofiltration membrane elements is established. The coefficients of exponential function polynomial are solved by using orthogonal design and mathematics fitting. The operating characteristics ofnanofiltration membrane elements are graphically analyzed. The multivariate operating characteristics of a series of nanofiltration membrane elements are systematically analyzed, thus providing a reference for the series of nanofiltration system design and operation.%建立了表征系列不同脱盐率的纳滤膜元件运行特性的幂指函数多项式,运用正交设计与数学拟合方法求解了幂指函数多项式的各项系数,图解分析了纳滤膜元件的诸项运行特性,从而系统分析了系列纳滤膜元件的多因素运行特性,为各种不同脱盐率纳滤系统的设计与运行提供了参考依据.

  7. Operational Characteristics of Para-transit Modes in Akure, Nigeria ...

    African Journals Online (AJOL)

    Operational Characteristics of Para-transit Modes in Akure, Nigeria. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... Data on the cogent indices of metering operations, attributes of operators and patrons of para-transit modes were ...

  8. Operating characteristic analysis of a 400 mH class HTS DC reactor in connection with a laboratory scale LCC type HVDC system

    Science.gov (United States)

    Kim, Sung-Kyu; Kim, Kwangmin; Park, Minwon; Yu, In-Keun; Lee, Sangjin

    2015-11-01

    High temperature superconducting (HTS) devices are being developed due to their advantages. Most line commutated converter based high voltage direct current (HVDC) transmission systems for long-distance transmission require large inductance of DC reactor; however, generally, copper-based reactors cause a lot of electrical losses during the system operation. This is driving researchers to develop a new type of DC reactor using HTS wire. The authors have developed a 400 mH class HTS DC reactor and a laboratory scale test-bed for line-commutated converter type HVDC system and applied the HTS DC reactor to the HVDC system to investigate their operating characteristics. The 400 mH class HTS DC reactor is designed using a toroid type magnet. The HVDC system is designed in the form of a mono-pole system with thyristor-based 12-pulse power converters. In this paper, the investigation results of the HTS DC reactor in connection with the HVDC system are described. The operating characteristics of the HTS DC reactor are analyzed under various operating conditions of the system. Through the results, applicability of an HTS DC reactor in an HVDC system is discussed in detail.

  9. Research about reactor operator's personability characteristics and performance

    Energy Technology Data Exchange (ETDEWEB)

    Wei Li; He Xuhong; Zhao Bingquan [Tsinghua Univ., Institute of Nuclear Energy Technology, Beijing (China)

    2003-03-01

    To predict and evaluate the reactor operator's performance by personality characteristics is an important part of reactor operator safety assessment. Using related psychological theory combined with the Chinese operator's fact and considering the effect of environmental factors to personality analysis, paper does the research about the about the relationships between reactor operator's performance and personality characteristics, and offers the reference for operator's selection, using and performance in the future. (author)

  10. Characteristics of Managing Operational Banking Risk

    Directory of Open Access Journals (Sweden)

    Adela Socol

    2008-12-01

    Full Text Available The objective of this paper is to provide a global perspective of the operational risk from a banking societies’ viewpoint. We describe the main regulations and settlements in the field and examine the various approaches of the operational banking risk. The paper presents the need of banks to managing operational risk. We study comparatively for a banking society the capital charge for covering the operational risk under the basic indicator approach and under the standardized approach. We present a case study of implementing current capital requirements at the level of a Romanian banking society. From the theoretical approach and from the description of quantifying of operational banking risk, the results of this study insist on the importance of measuring of operational banking risk and identifies major issues that need to be considered to improve the managing operational banking risk.

  11. Feedback analysis of transimpedance operational amplifier circuits

    DEFF Research Database (Denmark)

    Bruun, Erik

    1993-01-01

    The transimpedance or current feedback operational amplifier (CFB op-amp) is reviewed and compared to a conventional voltage mode op-amp using an analysis emphasizing the basic feedback characteristics of the circuit. With this approach the paradox of the constant bandwidth obtained from CFB op...

  12. Performance Analysis of an Evaporator for a Diesel Engine–Organic Rankine Cycle (ORC Combined System and Influence of Pressure Drop on the Diesel Engine Operating Characteristics

    Directory of Open Access Journals (Sweden)

    Chen Bei

    2015-06-01

    Full Text Available The main purpose of this research is to analyze the performance of an evaporator for the organic Rankine cycle (ORC system and discuss the influence of the evaporator on the operating characteristics of diesel engine. A simulation model of fin-and-tube evaporator of the ORC system is established by using Fluent software. Then, the flow and heat transfer characteristics of the exhaust at the evaporator shell side are obtained, and then the performance of the fin-and-tube evaporator of the ORC system is analyzed based on the field synergy principle. The field synergy angle (β is the intersection angle between the velocity vector and the temperature gradient. When the absolute values of velocity and temperature gradient are constant and β < 90°, heat transfer enhancement can be achieved with the decrease of the β. When the absolute values of velocity and temperature gradient are constant and β >90°, heat transfer enhancement can be achieved with the increase of the β. Subsequently, the influence of the evaporator of the ORC system on diesel engine performance is studied. A simulation model of the diesel engine is built by using GT–Power software under various operating conditions, and the variation tendency of engine power, torque, and brake specific fuel consumption (BSFC are obtained. The variation tendency of the power output and BSFC of diesel engine–ORC combined system are obtained when the evaporation pressure ranges from 1.0 MPa to 3.5 MPa. Results show that the field synergy effect for the areas among the tube bundles of the evaporator main body and the field synergy effect for the areas among the fins on the windward side are satisfactory. However, the field synergy effect in the areas among the fins on the leeward side is weak. As a result of the pressure drop caused by the evaporator of the ORC system, the diesel engine power and torque decreases slightly, whereas the BSFC increases slightly with the increase of exhaust back

  13. Diagnostic sensitivity of serum carcinoembryonic antigen, carbohydrate antigen 19-9, alpha-fetoprotein, and beta-human chorionic gonadotropin in esophageal carcinoma (receiver operating characteristic curve analysis

    Directory of Open Access Journals (Sweden)

    Bhawna Bagaria

    2015-01-01

    Full Text Available Background: Esophageal carcinomas are very lethal disease relatively unresponsive to therapy. The continued development of new and more effective chemotherapeutic agents and regimens offers hope that in the future, this carcinoma may be amenable to either more effective palliative treatment or possibly increased cure. We, therefore, aimed to evaluate the marker with best diagnostic sensitivity in esophageal carcinoma. Materials and Methods: Serum carcinoembryonic antigen (CEA, carbohydrate antigen 19-9 (CA19-9, alpha-fetoprotein (AFP, and beta-human chorionic gonadotropin (β-HCG levels were assessed in healthy subjects (n = 50 and patients (n = 50 initially diagnosed of esophageal carcinoma by endoscopic examination and biopsy before receiving any therapy. The data were analyzed using SPSS software version 10.0 (SPSS Inc. USA and MedCalc to estimate mean ± standard deviation, the significance of the observed differences (P value, for calculating sensitivity and for plotting receiver operating characteristic curves. Results: Sensitivity of CEA, CA19-9, AFP, and β-HCG detected in esophagus cancer was 38%, 18%, 10%, and 26% respectively. Conclusion: From the above studied markers, CEA has the highest sensitivity followed by β-HCG, CA19-9 and AFP. Although the sensitivity of tumor markers in esophagus cancer is low, they may be useful additional parameter in the prediction of neoplasms involved at the early stage of tumor growth.

  14. Prediction of Abdominal Visceral Obesity From Body Mass Index,Waist Circumference and Waist-hip Ratio in Chinese Adults:Receiver Operating Characteristic Curves Analysis

    Institute of Scientific and Technical Information of China (English)

    WEI-PING JIA; JUN-XI LU; KUN-SAN XIANG; YU-QIAN BAO; HUI-JUAN LU; LEI CHEN

    2003-01-01

    To evaluate the sensitivity and specificity of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) measurements in diagnosing abdominal visceral obesity. Methods BMI, WC, and WHR were assessed in 690 Chinese adults (305 men and 385women) and compared with magnetic resonance imaging (MRI) measurements of abdominal visceral adipose tissue (VA). Receiver operating characteristic (ROC) curves were generated and used to determine the threshold point for each anthropometric parameter. Results 1) MRI showed that 61.7% of overweight/obese individuals (BMI≥25 kg/m2) and 14.2% of normal weight (BMI<25kg/m2) individuals had abdominal visceral obesity (VA≥ 100 cm2). 2) VA was positively correlated with each anthropometric variable, of which WC showed the highest correlation (r=0.73-0.77,P<0.001 ). 3) The best cut-off points for assessing abdominal visceral obesity were as followed: BMI of 26 kg/m2, WC of 90 cm, and WHR of 0.93, with WC being the most sensitive and specific factor. 4)Among subjects with BMI≥28 kg/m2 or WC≥95 cm, 95% of men and 90% of women appeared to have abdominal visceral obesity. Conclusion Measurements of BMI, WC, and WHR can be used in the prediction of abdominal visceral obesity, of which WC was the one with better accuracy.

  15. 农产品网店经营特点分析%Analysis of Operating Characteristic of Agricultural Products Online Store

    Institute of Scientific and Technical Information of China (English)

    李舒; 赵元凤

    2014-01-01

    The rapid development of e-commerce has changed the way people live,bringing people more convenient,reliable and timely products and services.Agricultural products as a basic element of people’s life have started relatively late in electronic commerce.This article introduced the current retail and the platform of agricultural products online store,then analyzed the present situation and characteristics of the agricultural products online store business,indicated the defects and deficiencies of the agricultural products online store management.So that providing a reference for agricultural products online store operation and development.%电子商务的快速发展改变了人们的生活方式,为人们带来更为便捷、可靠、及时的产品服务。农产品作为人们生活的基本要素,其电子商务的发展却起步较晚。介绍现行农产品网络零售的模式和依托平台,针对网店形式的农产品经营方式,分析总结农产品网店经营现状和特点,指出目前农产品网店经营存在的缺陷和不足,为农产品网店经营发展提供借鉴经验。

  16. Reliability of overbite depth indicator (ODI and anteroposterior dysplasia indicator (APDI in the assessment of different vertical and sagittal dental malocclusions: a receiver operating characteristic (ROC analysis

    Directory of Open Access Journals (Sweden)

    Farheen Fatima

    Full Text Available ABSTRACT Introduction: Differential diagnosis of skeletal and dental relationships is crucial for planning orthodontic treatment. Overbite depth indicator (ODI and anteroposterior dysplasia indicator (APDI had been introduced in the past for assessment of vertical and sagittal jaw relationships, respectively. Objective: The objectives of this study were to evaluate the reliability of ODI and APDI in overbite and Angle malocclusions, as well as assess their diagnostic reliability among males and females of different age groups. Material and Methods: This study was conducted using pretreatment dental casts and lateral cephalograms of 90 subjects. For ODI, subjects were divided into three groups based on overbite (normal overbite, open bite and deep bite. Likewise, the same subjects were divided for APDI into three groups, based on Angle's malocclusion classification (dental Class I, II and III malocclusions. Mann-Whitney U test was applied for comparison of study parameters regarding sex and different age groups. The mean values of ODI and APDI were compared among study groups by means of Kruskal-Wallis and post-hoc Dunnet T3 tests. The receiver operating characteristic (ROC curve was applied to test diagnostic reliability. Results: Insignificant differences were found for ODI and APDI angles, particularly in regards to sex and age. Significant intergroup differences were found in different overbite groups and Angle's classification for ODI and APDI, respectively (p < 0.001. ROC showed 91% and 88% constancy with dental pattern in ODI and APDI, respectively. Conclusions: ODI can reliably differentiate deep bite versus normal overbite and deep bite versus open bite. APDI can reliably differentiate dental Class I, II and III malocclusions.

  17. Human reliability analysis of control room operators

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Isaac J.A.L.; Carvalho, Paulo Victor R.; Grecco, Claudio H.S. [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil)

    2005-07-01

    Human reliability is the probability that a person correctly performs some system required action in a required time period and performs no extraneous action that can degrade the system Human reliability analysis (HRA) is the analysis, prediction and evaluation of work-oriented human performance using some indices as human error likelihood and probability of task accomplishment. Significant progress has been made in the HRA field during the last years, mainly in nuclear area. Some first-generation HRA methods were developed, as THERP (Technique for human error rate prediction). Now, an array of called second-generation methods are emerging as alternatives, for instance ATHEANA (A Technique for human event analysis). The ergonomics approach has as tool the ergonomic work analysis. It focus on the study of operator's activities in physical and mental form, considering at the same time the observed characteristics of operator and the elements of the work environment as they are presented to and perceived by the operators. The aim of this paper is to propose a methodology to analyze the human reliability of the operators of industrial plant control room, using a framework that includes the approach used by ATHEANA, THERP and the work ergonomics analysis. (author)

  18. Analysis of the p-i-n-structures Electrophysical Characteristics Influence on the Spectral Characteristics Sensitivity

    Directory of Open Access Journals (Sweden)

    V.N. Murashev

    2015-06-01

    Full Text Available In this paper the simulation of the silicon p-i-n-photodiodes spectral sensitivity characteristics was carried out. The analysis of the semiconductor material characteristics (the doping level, lifetime, surface recombination velocity, the construction and operation modes on the photosensitive structures characteristics in order to optimize them were investigated.

  19. Analysis of frequency characteristics of compliant mechanisms

    Institute of Scientific and Technical Information of China (English)

    WANG Wenjing; YU Yueqing

    2007-01-01

    Much work is needed for a further study on the dynamic analysis of compliant mechanisms to improve their performance and operational accuracy.This paper uses the finite element method to develop a dynamic equation of the compliant mechanism.Natural frequencies and modes are derived.Using the differentials of a stiffness matrix to design parameters,a method for calculating the sensitivity of natural frequency is presented.The numerical simulation results indicate that the design parameters have an impact on the frequency characteristics of the compliant mechanisms and the proposed method is more accurate and convenient for analyzing frequency characteristics.

  20. MPCV Exercise Operational Volume Analysis

    Science.gov (United States)

    Godfrey, A.; Humphreys, B.; Funk, J.; Perusek, G.; Lewandowski, B. E.

    2017-01-01

    In order to minimize the loss of bone and muscle mass during spaceflight, the Multi-purpose Crew Vehicle (MPCV) will include an exercise device and enough free space within the cabin for astronauts to use the device effectively. The NASA Digital Astronaut Project (DAP) has been tasked with using computational modeling to aid in determining whether or not the available operational volume is sufficient for in-flight exercise.Motion capture data was acquired using a 12-camera Smart DX system (BTS Bioengineering, Brooklyn, NY), while exercisers performed 9 resistive exercises without volume restrictions in a 1g environment. Data were collected from two male subjects, one being in the 99th percentile of height and the other in the 50th percentile of height, using between 25 and 60 motion capture markers. Motion capture data was also recorded as a third subject, also near the 50th percentile in height, performed aerobic rowing during a parabolic flight. A motion capture system and algorithms developed previously and presented at last years HRP-IWS were utilized to collect and process the data from the parabolic flight [1]. These motions were applied to a scaled version of a biomechanical model within the biomechanical modeling software OpenSim [2], and the volume sweeps of the motions were visually assessed against an imported CAD model of the operational volume. Further numerical analysis was performed using Matlab (Mathworks, Natick, MA) and the OpenSim API. This analysis determined the location of every marker in space over the duration of the exercise motion, and the distance of each marker to the nearest surface of the volume. Containment of the exercise motions within the operational volume was determined on a per-exercise and per-subject basis. The orientation of the exerciser and the angle of the footplate were two important factors upon which containment was dependent. Regions where the exercise motion exceeds the bounds of the operational volume have been

  1. OPERATION MODES AND CHARACTERISTICS OF PLASMA DIPOLE ANTENNA

    Directory of Open Access Journals (Sweden)

    Nikolay Nikolaevich Bogachev

    2014-02-01

    Full Text Available Existence modes of  surface electromagnetic wave on a plasma cylinder, operating modes and characteristics of the plasma antenna were studied in this paper. Solutions of the dispersion equation of surface wave were obtained for a plasma cylinder with finite radius for different plasma density values. Operation modes of the plasma asymmetric dipole antenna with finite length and radius were researched by numerical simulation. The electric field distributions of  the plasma antenna in near antenna field and the radiation pattern were obtained. These characteristics were compared to characteristics of the similar metal antenna. Numerical models verification was carried out by comparing of the counted and measured metal antenna radiation patterns.

  2. 49 CFR 234.205 - Operating characteristics of warning system apparatus.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Operating characteristics of warning system... characteristics of warning system apparatus. Operating characteristics of electromagnetic, electronic, or... limits within which the system is designed to operate....

  3. Feedback analysis of transimpedance operational amplifier circuits

    OpenAIRE

    Bruun, Erik

    1993-01-01

    The transimpedance or current feedback operational amplifier (CFB op-amp) is reviewed and compared to a conventional voltage mode op-amp using an analysis emphasizing the basic feedback characteristics of the circuit. With this approach the paradox of the constant bandwidth obtained from CFB op-amps is explained. It is demonstrated in a simple manner that the constant gain-bandwidth product of the conventional op-amp and the constant bandwidth of the CFB op-amp are both in accordance with bas...

  4. Framework for the analysis of crystallization operations

    DEFF Research Database (Denmark)

    Meisler, Kresten Troelstrup; Abdul Samad, Noor Asma Fazli Bin; Gernaey, Krist

    received increased attention due to the growing need to control more sophisticated production lines as well asto measure/monitor the final product characteristics. Crystallization operations involve a combination of several phenomena, and different kinetic models are required for their modeling. Growth......Crystallization is often applied in the production of salts and/oractive pharmaceutical ingredients (API), and the crystallization step is an essential part of the manufacturing process for many chemicals-based products.In recent years the monitoring and analysis of crystallization operations has...... of the crystals occurs in multiple dimensions and the relative rates of different growth and other kinetic phenomena control the shape and size distribution of the final product. Including several dimensions in the crystallization will allow a more general description of the kinetic phenomena...

  5. Fully automated (operational) modal analysis

    Science.gov (United States)

    Reynders, Edwin; Houbrechts, Jeroen; De Roeck, Guido

    2012-05-01

    Modal parameter estimation requires a lot of user interaction, especially when parametric system identification methods are used and the modes are selected in a stabilization diagram. In this paper, a fully automated, generally applicable three-stage clustering approach is developed for interpreting such a diagram. It does not require any user-specified parameter or threshold value, and it can be used in an experimental, operational, and combined vibration testing context and with any parametric system identification algorithm. The three stages of the algorithm correspond to the three stages in a manual analysis: setting stabilization thresholds for clearing out the diagram, detecting columns of stable modes, and selecting a representative mode from each column. An extensive validation study illustrates the accuracy and robustness of this automation strategy.

  6. Study on operating characteristic analysis of wind turbine%风力发电机运行特性分析研究

    Institute of Scientific and Technical Information of China (English)

    何宇; 姚刚; 殷旭升

    2012-01-01

    介绍了不同类型的风力发电机组的数学模型,采用PSASP软件,以WSCC3机9节点为例,分析了不同类型风电接入系统的暂态稳定性,通过仿真结果表明,对于小干扰稳定,风电接入后对系统的阻尼特性均有不同程度的改善;系统发生故障时,双馈风电机较直驱风电机的功率输出平滑,但双馈风电机的在电压恢复上更为有利。%The mathematic model of different wind power unit is introduced in this paper. Take WSCC 3 machine 9 bus system as an ex- ample, The transient stability of different wind power integrated into system is analyzed by PSASP, the damping characteristics of system in patients were improved to some degree after wind power integration;When a fault occurs, the power output of DFIG ( Doubly - Fed Induction Generator) is more smoother than PMSG( Permanent -Magnet Synchronous Generator), but for the recovery voltage, DFIG will be more favorable.

  7. 溪洛渡水电站泄洪系统运行特点%Analysis on Flood Discharging System Operation Characteristics of Xiluodu Hydropower Station

    Institute of Scientific and Technical Information of China (English)

    童伟; 杜利民; 叶云昭

    2013-01-01

    Xiluodu Hydropower Station is a hydropower project with narrow valley,high arch dam and huge flood discharge.The flood discharging system of Station consists of seven surface outlets,eight bottom outlets and four spillway tunnels,which are arranged according to the principle of "Decentralized flood discharging and zoned energy dissipation".The surface outlets are drop-in and the bottom outlets are upturned,and two nappes of surface and bottom outlets will collide in air and then fall into cushion pool for energy dissipation.Under normal operation mode,the bottom outlets are firstly used for flood discharge and then surface outlets,and the spillway tunnels is only used in the condition of outlets' discharge capacity being insufficient.%溪洛渡水电站具有“窄河谷、高拱坝、巨泄量”的特点,泄洪建筑物由7个泄洪表孔、8个泄洪深孔以及4条泄洪洞组成.泄洪系统按照“分散泄洪、分区消能”的原则布置.坝身泄洪采用表孔下跌式、深孔上翘式布置,两股水舌在空中碰撞后跌入水垫塘内紊动消能.正常运行方式下,优先开启坝身泄洪深孔,后开启泄洪表孔,泄洪洞宜在坝身泄流能力不足时参与泄洪.

  8. 大型风电机组限功率运行特性分析及其优化调度%Power-limited Operation Characteristic Analysis and Optimal Scheduling for Large Scale Wind Turbines

    Institute of Scientific and Technical Information of China (English)

    肖运启; 贺贯举

    2014-01-01

    近年来大量风电场的并网给电网安全运行带来困难,为此电网调度部门对所辖风电场提出了严格的限发要求。变速风电机组需要从传统的最大风能利用运行模式向限功率运行模式转变,由于风力机功率特性具有强非线性,运行模式的改变对风电机组以及风电场的控制策略提出了更高的设计要求。提出了一种考虑风电机组限功率运行状态优化的风电场功率调度策略。首先,基于小扰动分析方法分析了限功率运行下风电机组非线性模型的稳定特性;然后,提出了一种限功率运行状态评价指标;接下来,建立了风电场功率调度多目标优化模型,并基于遗传算法设计了求解策略。最后,结合实际算例验证了所提调度策略的有效性。%In recent years,a large number of wind farms have been connected to grid which causes difficulty in maintaining secure grid operations,consequently,the dispatch centers often need to require the wind farms to limit their power output strictly.As a result,the operating mode of wind turbines and wind farm needs to be transferred from traditional maximum wind energy tracking to power limited operating conditions. However,given the strong nonlinear characteristics of the turbines,changing operating mode requires more complex control strategies for both the wind turbines and wind farms.A wind farm power optimum dispatching strategy,considering the wind turbine power limited operation conditions,is proposed.A small disturbance analysis method is adopted to analyze the stability for power limited operations.An assessment index is presented to evaluate the operating modes.A multi-objective optimization model is established using genetic algorithms. Numerical examples are given to validate the efficiency of the strategy proposed.

  9. Design and Operational Characteristics of the Shuttle Coherent Wind Lidar

    Science.gov (United States)

    Amzajerdian, Farzin; Spiers, Gary D.; Peters, Bruce R.; Li, Ye; Blackwell, Timothy S.; Geary, Joseph M.

    1998-01-01

    NOAA has identified the measurement of atmospheric wind velocities as one of the key unmet data sets for its next generation of sensing platforms. The merits of coherent lidars for the measurement of atmospheric winds from space platforms have been widely recognized; however, it is only recently that several key technologies have advanced to a point where a compact, high fidelity system could be created. Advances have been made in the areas of the diode-pumped, eye-safe, solid state lasers and room temperature, wide bandwidth, semiconductor detectors operating in the near-infrared region. These new lasers can be integrated into efficient and compact optical systems creating new possibilities for the development of low-cost, reliable, and compact coherent lidar systems for wind measurements. Over the past five years, the University of Alabama in Huntsville (UAH) has been working toward further advancing the solid state coherent lidar technology for the measurement of atmospheric winds from space. As part of this effort, UAH had established the design characteristics and defined the expected performance for three different proposed space-based instruments: a technology demonstrator, an operational prototype, and a 7-year lifetime operational instrument. SPARCLE is an ambitious project that is intended to evaluate the suitability of coherent lidar for wind measurements, demonstrate the maturity of the technology for space application, and provide a useable data set for model development and validation. This paper describes the SPARCLE instrument's major physical and environmental design constraints, optical and mechanical designs, and its operational characteristics.

  10. Operant Variability: A Conceptual Analysis

    Science.gov (United States)

    Barba, Lourenco de Souza

    2012-01-01

    Some researchers claim that variability is an operant dimension of behavior. The present paper reviews the concept of operant behavior and emphasizes that differentiation is the behavioral process that demonstrates an operant relation. Differentiation is conceived as change in the overlap between two probability distributions: the distribution of…

  11. Classification of operational characteristics of commercial cup-anemometers

    Energy Technology Data Exchange (ETDEWEB)

    Friis Pedersen, T.; Schmidt Paulsen, U. [Risoe National Lab., Wind Energy and Atmospheric Physics Dept., Roskilde (Denmark)

    1999-03-01

    The present classification of cup-anemometers is based on a procedure for classification of operational characteristics of cup-anemometers that was proposed at the EWEC `97 conference in Dublin 1997. Three definitions of wind speed are considered. The average longitudinal wind speed (ID), the average horizontal wind speed (2D) and the average vector wind speed (3D). The classification is provided in these terms, and additionally, the turbulence intensities, which are defined from the same wind speed definitions. The commercial cup-anemometers have all been calibrated in wind tunnel for the normal calibrations and angular characteristics. Friction was measured by blywheel testing, where the surrounding temperatures were varied over a wide range. The characteristics of the cup-anemometers have been fitted to the heuristic dynamic model, and the response has been calculated in time domain for prescribed ranges of external operational conditions. The results are presented in ranges of maximum deviations of `measured` average wind speed. For each definition of wind speed and turbulence intensity, the cup-anemometers are ranked according to the most precise instrument. Finally, the most important systematic error sources are commented. (au)

  12. Spectral Characteristics of the Unitary Critical Almost-Mathieu Operator

    Science.gov (United States)

    Fillman, Jake; Ong, Darren C.; Zhang, Zhenghe

    2016-10-01

    We discuss spectral characteristics of a one-dimensional quantum walk whose coins are distributed quasi-periodically. The unitary update rule of this quantum walk shares many spectral characteristics with the critical Almost-Mathieu Operator; however, it possesses a feature not present in the Almost-Mathieu Operator, namely singularity of the associated cocycles (this feature is, however, present in the so-called Extended Harper's Model). We show that this operator has empty absolutely continuous spectrum and that the Lyapunov exponent vanishes on the spectrum; hence, this model exhibits Cantor spectrum of zero Lebesgue measure for all irrational frequencies and arbitrary phase, which in physics is known as Hofstadter's butterfly. In fact, we will show something stronger, namely, that all spectral parameters in the spectrum are of critical type, in the language of Avila's global theory of analytic quasiperiodic cocycles. We further prove that it has empty point spectrum for each irrational frequency and away from a frequency-dependent set of phases having Lebesgue measure zero. The key ingredients in our proofs are an adaptation of Avila's Global Theory to the present setting, self-duality via the Fourier transform, and a Johnson-type theorem for singular dynamically defined CMV matrices which characterizes their spectra as the set of spectral parameters at which the associated cocycles fail to admit a dominated splitting.

  13. Condition Monitoring Of Operating Pipelines With Operational Modal Analysis Application

    Directory of Open Access Journals (Sweden)

    Mironov Aleksey

    2015-12-01

    Full Text Available In the petroleum, natural gas and petrochemical industries, great attention is being paid to safety, reliability and maintainability of equipment. There are a number of technologies to monitor, control, and maintain gas, oil, water, and sewer pipelines. The paper focuses on operational modal analysis (OMA application for condition monitoring of operating pipelines. Special focus is on the topicality of OMA for definition of the dynamic features of the pipeline (frequencies and mode shapes in operation. The research was conducted using two operating laboratory models imitated a part of the operating pipeline. The results of finite-element modeling, identification of pipe natural modes and its modification under the influence of virtual failure are discussed. The work considers the results of experimental research of dynamic behavior of the operating pipe models using one of OMA techniques and comparing dynamic properties with the modeled data. The study results demonstrate sensitivity of modal shape parameters to modification of operating pipeline technical state. Two strategies of pipeline repair – with continuously condition-based monitoring with proposed technology and without such monitoring, was discussed. Markov chain reliability models for each strategy were analyzed and reliability improvement factor for proposed technology of monitoring in compare with traditional one was evaluated. It is resumed about ability of operating pipeline condition monitoring by measuring dynamic deformations of the operating pipe and OMA techniques application for dynamic properties extraction.

  14. Discriminating Threshold of Driving Fatigue Based on the Electroencephalography Sample Entropy by Receiver Operating Characteristic Curve Analysis%基于ROC曲线的驾驶疲劳脑电样本熵判定阈值研究

    Institute of Scientific and Technical Information of China (English)

    赵晓华; 许士丽; 荣建; 张兴俭

    2013-01-01

    为了获得客观而准确的驾驶疲劳判别阈值,采用驾驶模拟实验研究方法,采集驾驶员在清醒及疲劳状态下的脑电信号,对比分析不同状态下脑电信号的时域特征,选取表征信号复杂程度的样本熵作为驾驶疲劳判别指标,并利用受试者工作特性曲线(receiver operating characteristic curve,ROC)分析方法,确定基于脑电信号样本熵值的驾驶疲劳判别阈值.研究结果表明:脑电信号样本熵值处于区间(0.32,0.71)时,驾驶员处于疲劳过渡时期,可能出现疲劳特征;脑电信号样本熵值小于阈值0.605时,判定驾驶员处于驾驶疲劳状态,准确率为0.95,该值可作为基于脑电信号样本熵的驾驶疲劳判定阈值.%In order to acquire an objective and accurate driving fatigue threshold, electroencephalography (EEG) signals of drivers were collected from driving simulator, and the time-domain characteristics of EGG signals of drivers in sober and mental fatigue states were comparatively analyzed. Considering the different complexity of EEG signals in sober and fatigue states, the sample entropy of EEG signals were calculated to characterize the complexity of signals, and used as the index for identifying driving fatigue. Based on the obtained EGG sample entropy, the receiver operating characteristic (ROC) curve analysis was introduced to obtain the discriminating threshold of driving fatigue. The results indicate that when the EEG sample entropy value is between (0.32, 0.71) , the driver is in the transitional period of fatigue, may be in a fatigue state; the sample entropy of less than 0.605 can be identified as the threshold of driving fatigue, and the accuracy is 0.95.

  15. Prognostic Analysis System and Methods of Operation

    Science.gov (United States)

    MacKey, Ryan M. E. (Inventor); Sneddon, Robert (Inventor)

    2014-01-01

    A prognostic analysis system and methods of operating the system are provided. In particular, a prognostic analysis system for the analysis of physical system health applicable to mechanical, electrical, chemical and optical systems and methods of operating the system are described herein.

  16. Theoretical Analysis and Simulation of BJFET Obstructive Characteristics

    Institute of Scientific and Technical Information of China (English)

    ZENG Yun; YAN Min; YAN Yong-hong; FAN Wei

    2005-01-01

    A new bipolar junction field-effect transistor (BJFET) was described. The theoretical analysis and computer simulation of BJFET obstructive characteristic are achieved. The gate bias voltage affects the BJFET obstructive voltage greatly. The BJFET obstructive characteristic is relevant to structure parameters of channel width W and channel length L.The decrease-bias-voltage operation can weaken the device obstructive characteristic. The forward turn in device forward obstructive region can also affect the BJFET obstructive characteristic. BJFET has a good high temperature obstructive characteristic and can be applying to high temperature status as high voltage switch devices.

  17. The effects of criterion variability on relative operating characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Brown, W.S. [Brookhaven Natl. Lab., Bldg. 130, Upton, NY 11973-5000 (United States); Emmerich, D.S. [State Univ. of New York at Stony Brook, Stony Brook, NY 11974 (United States)

    1995-05-01

    The form of the relative operating characteristic (ROC) describing auditory detection typically differs from that expected based on the assumption that the observer`s responses reflect underlying distributions that are normal and of equal variance [e.g., Green and Swets, {ital Signal} {ital Detection} {ital Theory} {ital and} {ital Psychophysics}]. Specifically, it is found that binormal ROCs often have slopes less than one, and are not strictly linear [Watson {ital et} {ital al}., 283--288 (1964)]. It has been suggested that nonlinear binormal ROCs may be the result of extreme criteria being more variable than those more centrally positioned [Emmerich and Binder, J. Acoust. Soc. Am. Suppl. 1 {bold 65}, S59 (1979)]. The forms of rating ROCs obtained in an experiment designed to reveal the effects of such variability were consistent with the proposition that criteria associated with ``no`` responses are more variable than those associated with ``yes`` responses. Criterion operating characteristics [Wickelgren, J. Math. Psychol. {bold 5}, 102--122], which reflect the relative locations and variances of the boundaries of confidence categories, favored the same interpretation. It is concluded that the variability of criteria defining categories of rated confidence is sizable and not necessarily constant across criteria, and that such variability significantly influences the forms of empirical ROCs determined using confidence ratings in auditory signal detection.

  18. Water Hammer Analysis by Characteristic Method

    Directory of Open Access Journals (Sweden)

    A. R. Lohrasbi

    2008-01-01

    Full Text Available Rapid changes in the velocity of fluid in closed conduits generate large pressure, which are transmitted through the system with the speed of sound. When the fluid medium is a liquid the pressure surges and related phenomena are described as water hammer. Water hammer is caused by normal operation of the system, such as valve opening or closure, pump starts and stoppages and by abnormal condition, such as power failure. Problem statement: Water hammer causes the additional pressure in water networks. This pressure maybe defects on pipes and connections. The likely effects of water hammer must be taken into account in the structural design of pipelines and in the design of operating procedures for pumps, valves, etc. Approach: The physical phenomena of water hammer and the mathematical model which provides the basis for design computations are described. Most water hammer analysis involves computer solution by the method of characteristics. In this study water hammer is modelled with this method and effect of valve opening and closure will be surveyed with a program that is used for this purpose and with a numerical example. Results: The more rapid the closure of the valve, the more rapid is the change in momentum and hence, greater is the additional pressure developed. Conclusions/Recommendations: For preventing of water hammer defects, is recommended that valves should be open or closed slowly. Also with using the method of characteristics, we can modelled all pipe networks, and see the affects of water hammer.

  19. Human dynamics scaling characteristics for aerial inbound logistics operation

    Science.gov (United States)

    Wang, Qing; Guo, Jin-Li

    2010-05-01

    In recent years, the study of power-law scaling characteristics of real-life networks has attracted much interest from scholars; it deviates from the Poisson process. In this paper, we take the whole process of aerial inbound operation in a logistics company as the empirical object. The main aim of this work is to study the statistical scaling characteristics of the task-restricted work patterns. We found that the statistical variables have the scaling characteristics of unimodal distribution with a power-law tail in five statistical distributions - that is to say, there obviously exists a peak in each distribution, the shape of the left part closes to a Poisson distribution, and the right part has a heavy-tailed scaling statistics. Furthermore, to our surprise, there is only one distribution where the right parts can be approximated by the power-law form with exponent α=1.50. Others are bigger than 1.50 (three of four are about 2.50, one of four is about 3.00). We then obtain two inferences based on these empirical results: first, the human behaviors probably both close to the Poisson statistics and power-law distributions on certain levels, and the human-computer interaction behaviors may be the most common in the logistics operational areas, even in the whole task-restricted work pattern areas. Second, the hypothesis in Vázquez et al. (2006) [A. Vázquez, J. G. Oliveira, Z. Dezsö, K.-I. Goh, I. Kondor, A.-L. Barabási. Modeling burst and heavy tails in human dynamics, Phys. Rev. E 73 (2006) 036127] is probably not sufficient; it claimed that human dynamics can be classified as two discrete university classes. There may be a new human dynamics mechanism that is different from the classical Barabási models.

  20. Analysis on steady-state mathematical models and operating characteristics of brushless doubly-fed machine%无刷双馈电机稳态数学模型和运行特性分析

    Institute of Scientific and Technical Information of China (English)

    韩力; 罗杰; 王华; 潘红广

    2013-01-01

    为了深入研究笼型转子无刷双馈电机(brushless doubly-fed machine,BDFM)的稳态特性,从耦合电路出发,给出了BDFM的基本方程式,进而分析并得到了BDFM电流、有功功率、无功功率、电磁转矩和功率因数的数学模型.在此基础上,通过Matlab对1台样机进行了仿真,获得了BDFM的矩角特性、矩频特性、功角特性、无功特性、功率因数特性和V形曲线,并利用数学模型分析了BDFM的能量转换.结果表明:BDFM的各种稳态特性均可表示为控制绕组电压、频率和功角这3个变量的函数,所提出的模型简化了BDFM稳态特性的分析方法,为进一步研究BDFM的稳定性和控制策略奠定了理论基础.%To further study the steady-state characteristics of brushless doubly-fed machine(BDFM) with squirrel-rotor,the basic equations are given according to the coupling circuits of BDFM.And then,the mathematical models of BDFM current,active power,reactive power,electromagnetic torque and power factor are analyzed and derived respectively.Furthermore,the characteristics of torque-angle,torquefrequency,power-angle,reactive power,power factor and V-shaped curve of BDFM are obtained respectively by MATLAB simulation of a prototype.The energy conversion of BDFM is analyzed by the proposed mathematical models at the same time.The results show that all the steady-state characteristics of BDFM can be expressed as the functions of the control windings voltage,frequency and the power angle.The proposed model simplifies the analysis of the steady-state characteristics of BDFM and provides a theoretical foundation for the further study on operating stability and control strategy of BDFM.

  1. Special issue on Operational Modal Analysis

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Brincker, Rune

    2010-01-01

    Operational Modal Analysis (OMA) is not really a new discipline; it has been present from the very beginning of the development of modal testing and analysis going back to the sixties and early seventies.......Operational Modal Analysis (OMA) is not really a new discipline; it has been present from the very beginning of the development of modal testing and analysis going back to the sixties and early seventies....

  2. Repository operational criteria comparative analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hageman, J.P.; Chowdhury, A.H. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses

    1994-06-01

    The objective of the ``Repository Operational Criteria (ROC) Feasibility Studies`` (or ROC task) was to conduct comprehensive and integrated analyses of repository design, construction, and operations criteria in 10 CFR Part 60 regulations considering the interfaces among the components of the regulations and impacts of any potential changes to those regulations. The ROC task addresses regulatory criteria and uncertainties related to the preclosure aspects of the geologic repository. Those parts of 10 CFR Part 60 that require routine guidance or minor changes to the rule were addressed in Hageman and Chowdhury, 1992. The ROC task shows a possible need for further regulatory clarity, by major changes to the rule, related to the design bases and siting of a geologic repository operations area and radiological emergency planning in order to assure defense-in-depth. The analyses, presented in this report, resulted in the development and refinement of regulatory concepts and their supporting rationale for recommendations for potential major changes to 10 CFR Pan 0 regulations.

  3. Tank Farm Operations Surveillance Automation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    MARQUEZ, D.L.

    2000-12-21

    The Nuclear Operations Project Services identified the need to improve manual tank farm surveillance data collection, review, distribution and storage practices often referred to as Operator Rounds. This document provides the analysis in terms of feasibility to improve the manual data collection methods by using handheld computer units, barcode technology, a database for storage and acquisitions, associated software, and operational procedures to increase the efficiency of Operator Rounds associated with surveillance activities.

  4. Uncertainty calculation in (operational) modal analysis

    Science.gov (United States)

    Pintelon, R.; Guillaume, P.; Schoukens, J.

    2007-08-01

    In (operational) modal analysis the modal parameters of a structure are identified from the response of that structure to (unmeasurable operational) perturbations. A key issue that remains to be solved is the calculation of uncertainty bounds on the estimated modal parameters. The present paper fills this gap. The theory is illustrated by means of a simulation and a real measurement example (operational modal analysis of a bridge).

  5. Man-Vehicle Systems Research Facility - Design and operating characteristics

    Science.gov (United States)

    Shiner, Robert J.; Sullivan, Barry T.

    1992-01-01

    This paper describes the full-mission flight simulation facility at the NASA Ames Research Center. The Man-Vehicle Systems Research Facility (MVSRF) supports aeronautical human factors research and consists of two full-mission flight simulators and an air-traffic-control simulator. The facility is used for a broad range of human factors research in both conventional and advanced aviation systems. The objectives of the research are to improve the understanding of the causes and effects of human errors in aviation operations, and to limit their occurrence. The facility is used to: (1) develop fundamental analytical expressions of the functional performance characteristics of aircraft flight crews; (2) formulate principles and design criteria for aviation environments; (3) evaluate the integration of subsystems in contemporary flight and air traffic control scenarios; and (4) develop training and simulation technologies.

  6. Applicability Limits of Operational Modal Analysis to Operational Wind Turbines

    DEFF Research Database (Denmark)

    Tcherniak, D.; Chauhan, Shashank; Hansen, Morten Hartvig

    2011-01-01

    Operational Modal Analysis (OMA) is one of the branches of experimental modal analysis which allows extracting modal parameters based on measuring only the responses of a structure under ambient or operational excitation which is not needed to be measured. This makes OMA extremely attractive...... to modal analysis of big structures such as wind turbines where providing measured excitation force is an extremely difficult task. One of the main OMA assumption concerning the excitation is that it is distributed randomly both temporally and spatially. Obviously, closer the real excitation...... is to the assumed one, better modal parameter estimation one can expect. Traditionally, wind excitation is considered as a perfect excitation obeying the OMA assumptions. However, the present study shows that the aeroelastic phenomena due to rotor rotation dramatically changes the character of aerodynamic...

  7. Ram accelerator operating characteristics at elevated fill pressures

    Energy Technology Data Exchange (ETDEWEB)

    Bundy, C.; Knowlen, C.; Bruckner, A.P. [Washington Univ., Seattle, WA (United States). Aerospace and Energetics Research Program

    2000-11-01

    An experimental investigation of the starting and operational characteristics of a 38-mm bore ram accelerator with propellant fill pressures greater than 5 MPa is in progress. Successful starts with 60 - 124 gm projectiles have been achieved using methane/oxygen/nitrogen propellants at fill pressures ranging from 6 to 15 MPa. At fill pressures of 8.5 MPa and above, it was found that projectiles having the nominal throat diameter (29 mm) required a minimum entrance velocity of 1250 m/s, which is about 100 m/s faster than the minimum needed to successfully start the ram accelerator at fill pressures below 7.5 MPa. Projectiles with a reduced throat diameter (25 mm) and a solid magnesium nose cone were successfully started at fill pressures up to 15 MPa with entrance velocities around 1300 m/s. The average accelerations achieved using high pressure stages were in general less than predicted for thermally choked operation by the Boltzmann equation of state. (orig.)

  8. The Teodorescu Operator in Clifford Analysis

    Institute of Scientific and Technical Information of China (English)

    F.BRACKX; H.De SCHEPPER; M.E.LUNA-ELIZARRAR(A)S; M.SHAPIRO

    2012-01-01

    Euclidean Clifford analysis is a higher dimensional function theory centred around monogenic functions,i.e.,null solutions to a first order vector valued rotation invariant differential operator (θ) called the Dirac operator.More recently,Hermitian Clifford analysis has emerged as a new branch,offering yet a refinement of the Euclidean case; it focuses on the simultaneous null solutions,called Hermitian monogenic functions,to two Hermitian Dirac operators (θ)z_ and (θ)z_(+) which are invariant under the action of the unitary group.In Euclidean Clifford analysis,the Teodorescu operator is the right inverse of the Dirac operator (θ).In this paper,Teodorescu operators for the Hermitian Dirac operators (θ)z_ and (θ)z(+) are constructed.Moreover,the structure of the Euclidean and Hermitian Teodorescu operators is revealed by analyzing the more subtle behaviour of their components.Finally,the obtained inversion relations are still refined for the differential operators issuing from the Euclidean and Hermitian Dirac operators by splitting the Clifford algebra product into its dot and wedge parts.Their relationship with several complex variables theory is discussed.

  9. [Characteristics of the Chinese human milk banks' operation].

    Science.gov (United States)

    2017-08-02

    Objective: To assess the operation status of human milk banks in the mainland of China. Method: This retrospective study included a consecutive series of 14 human milk banks in the mainland of China from March 2013 to December 2016. The opened date, condition of donated breast milk, characteristics of donors and clinical application of donated breast milk were analyzed. Result: There were 14 human milk banks successively founded in mainland China from March 2013 to December 2016. The number of human milk banks, the amount of donated breast milk, the number of eligible donors and the times of donation had increased each year. Howere, the operation status among these milk banks varied greatly. Among them, one human milk bank has newly opened without relevant data, 6 banks could accept frozen breast milk, and the remaining 7 banks could only collect breast milk by the nurses in the bank. Among the 3 121 eligible donors, 1 404 (45.0%) donated less than 3 times, 2 553 (81.8%) aged 25 to 35 years, 2 828 (90.6%) had term delivery, 2 409 (77.2%) began donation one month after birth, 1 798 (57.6%) were company employees and housewives and 1 891 (60.6%) had bachelor or higher degree. The use of donor breast milk, the number of recipients and the average received amount of breast milk every person varied greatly among these banks. Conclusion: The human milk banking developed quickly in the mainland of China. Howere, the number of donors and the amount of donated breast milk which could not meet the clinical demands should be improved. And it was urgent to establish the standards or guidelines of the human milk banking as soon as possible in China.

  10. IMPROVEMENT OF OPERATIONAL CHARACTERISTICS OF THE AIRCRAFT WITH A DEFORMABLE COMBINED WING

    OpenAIRE

    Zinchenko, Dmytro; Ortamevzi, Gurkan

    2015-01-01

    In this article studied the characteristics of the experimental and numerical models, as well as a comparative analysis of performance of flying machines with different types of bearing surfaces with equal specific wing loading G / S.Development of experimental aircrafts with soft wings due to the need to increase the operation of  aircrafts.The results of wind tunnel test has performed using a general purpose classical scheme for models plane (Aeroprakt A-20) and are provided with two differ...

  11. Natural Characteristics and Operational Modal Analysis of Wind Turbine Gearbox%风电齿轮箱固有特性分析及工作模态测试

    Institute of Scientific and Technical Information of China (English)

    石万凯; 郑站强; 宋丽鸽

    2012-01-01

    The drive and structure system coupled dynamics model of wind turbine gearbox was built using finite element method, in which four spring elements was used to simulate each bearing connection.The inherent characteristics of the gearbox under practical constraint were analyzed to get its first 20 modal frequencies and modal shapes.Meanwhile a test was also carried out to obtain the gearbox's modal parameters in 5 different conditions using operational modal identification technique based on response data.The results of test and finite element analysis were consistent by comparison.It indicated that the coupled dynamics model was correct, so the model could be used to analyze gearbox instead of physical model.%采用有限元的方法建立了风电齿轮箱传动系统与结构系统的耦合动力学模型.在轴承连接处采用4个弹簧单元进行模拟,分析了齿轮箱在实际约束条件下的固有特性,得到了其前20阶模态频率与振型.同时对齿轮箱进行了实验,采用基于响应数据的工作模态辨识技术,得到其在5种不同工况下的模态参数,并把得到的参数和有限元的分析结果进行对比,两者的结果基本吻合.结果表明建立的耦合动力学模型是正确的,可以用它来替代实物模型对齿轮箱进行分析.

  12. Stochastic Modelling and Analysis of Warehouse Operations

    NARCIS (Netherlands)

    Y. Gong (Yeming)

    2009-01-01

    textabstractThis thesis has studied stochastic models and analysis of warehouse operations. After an overview of stochastic research in warehouse operations, we explore the following topics. Firstly, we search optimal batch sizes in a parallel-aisle warehouse with online order arrivals. We employ a

  13. Therapy operating characteristic curves: tools for precision chemotherapy.

    Science.gov (United States)

    Barrett, Harrison H; Alberts, David S; Woolfenden, James M; Caucci, Luca; Hoppin, John W

    2016-04-01

    The therapy operating characteristic (TOC) curve, developed in the context of radiation therapy, is a plot of the probability of tumor control versus the probability of normal-tissue complications as the overall radiation dose level is varied, e.g., by varying the beam current in external-beam radiotherapy or the total injected activity in radionuclide therapy. This paper shows how TOC can be applied to chemotherapy with the administered drug dosage as the variable. The area under a TOC curve (AUTOC) can be used as a figure of merit for therapeutic efficacy, analogous to the area under an ROC curve (AUROC), which is a figure of merit for diagnostic efficacy. In radiation therapy, AUTOC can be computed for a single patient by using image data along with radiobiological models for tumor response and adverse side effects. The mathematical analogy between response of observers to images and the response of tumors to distributions of a chemotherapy drug is exploited to obtain linear discriminant functions from which AUTOC can be calculated. Methods for using mathematical models of drug delivery and tumor response with imaging data to estimate patient-specific parameters that are needed for calculation of AUTOC are outlined. The implications of this viewpoint for clinical trials are discussed.

  14. Operational characteristics optimization of human-computer system

    Directory of Open Access Journals (Sweden)

    Zulquernain Mallick

    2010-09-01

    Full Text Available Computer operational parameters are having vital influence on the operators efficiency from readability viewpoint. Four parameters namely font, text/background color, viewing angle and viewing distance are analyzed. The text reading task, in the form of English text, was presented on the computer screen to the participating subjects and their performance, measured in terms of number of words read per minute (NWRPM, was recorded. For the purpose of optimization, the Taguchi method is used to find the optimal parameters to maximize operators’ efficiency for performing readability task. Two levels of each parameter have been considered in this study. An orthogonal array, the signal-to-noise (S/N ratio and the analysis of variance (ANOVA were employed to investigate the operators’ performance/efficiency. Results showed that Times Roman font, black text on white background, 40 degree viewing angle and 60 cm viewing distance, the subjects were quite comfortable, efficient and read maximum number of words per minute. Text/background color was dominant parameter with a percentage contribution of 76.18% towards the laid down objective followed by font type at 18.17%, viewing distance 7.04% and viewing angle 0.58%. Experimental results are provided to confirm the effectiveness of this approach.

  15. Operational morbidity analysis: ophthalmic presentations during Operation TELIC.

    Science.gov (United States)

    Ollerton, J E; Hodgetts, T J

    2010-03-01

    This paper analyses all ophthalmic attendances to a deployed emergency department (ED) in Iraq to identify patterns of injury to optimise patient care, plan equipment tables for future operations and emphasise need for prevention of ocular morbidity. The Academic Department of Military Emergency Medicine at the Royal Centre for Defence Medicine in Birmingham maintains an electronic database with derails on all attendances to the emergency departments deployed on Operations. This Operational Emergency Department Attendance Register (OpEDAR) was searched for all patients with medical classification of Ophthalmology over a 52 month period between 1 March 2003 and 30 June 2007. During this period 30,195 patients were seen in the ED on Operation Telic and are available for analysis. Patients with ophthalmic complaints account for 5.3% of all presentations to the ED and rank as the 7th most common reason for attendance. This paper identifies patterns of injury to enable future planning of equipment tables and identifies the need for prevention of injury wherever possible. Implications on days lost from full active duty for the injured can be extrapolated. More data needs to be collated on the use of eye protection and the relevance of contact lenses in deployed personnel with eye injuries.

  16. Competition analysis on the operating system market using principal component analysis

    Directory of Open Access Journals (Sweden)

    Brătucu, G.

    2011-01-01

    Full Text Available Operating system market has evolved greatly. The largest software producer in the world, Microsoft, dominates the operating systems segment. With three operating systems: Windows XP, Windows Vista and Windows 7 the company held a market share of 87.54% in January 2011. Over time, open source operating systems have begun to penetrate the market very strongly affecting other manufacturers. Companies such as Apple Inc. and Google Inc. penetrated the operating system market. This paper aims to compare the best-selling operating systems on the market in terms of defining characteristics. To this purpose the principal components analysis method was used.

  17. Analysis and Synthesis of Delta Operator Systems

    CERN Document Server

    Yang, Hongjiu; Shi, Peng; Zhao, Ling

    2012-01-01

    This book is devoted to analysis and design on delta operator systems. When sampling is fast, a dynamical system will become difficult to control, which can be seen in wide real world applications. Delta operator approach is very effective to deal with fast sampling systems. Moreover, it is easy to observe and analyze the control effect with different sampling periods in delta operator systems. The framework of this book has been carefully constructed for delta operator systems to handle sliding mode control, time delays, filter design, finite frequency and networked control. These problems indeed are especially important and significant in automation and control systems design. Through the clear framework of the book, readers can easily go through the learning process on delta operator systems via a precise and comfortable learning sequence. Following this enjoyable trail, readers will come out knowing how to use delta operator approach to deal with control problems under fast sampling case. This book should...

  18. Noncommutative analysis, operator theory and applications

    CERN Document Server

    Cipriani, Fabio; Colombo, Fabrizio; Guido, Daniele; Sabadini, Irene; Sauvageot, Jean-Luc

    2016-01-01

    This book illustrates several aspects of the current research activity in operator theory, operator algebras and applications in various areas of mathematics and mathematical physics. It is addressed to specialists but also to graduate students in several fields including global analysis, Schur analysis, complex analysis, C*-algebras, noncommutative geometry, operator algebras, operator theory and their applications. Contributors: F. Arici, S. Bernstein, V. Bolotnikov, J. Bourgain, P. Cerejeiras, F. Cipriani, F. Colombo, F. D'Andrea, G. Dell'Antonio, M. Elin, U. Franz, D. Guido, T. Isola, A. Kula, L.E. Labuschagne, G. Landi, W.A. Majewski, I. Sabadini, J.-L. Sauvageot, D. Shoikhet, A. Skalski, H. de Snoo, D. C. Struppa, N. Vieira, D.V. Voiculescu, and H. Woracek.

  19. 有机静电感应三级管动作特性的实验分析%Experimental analysis of operating characteristics of organic semiconductor static induction transistor

    Institute of Scientific and Technical Information of China (English)

    薛严冰; 王东兴

    2006-01-01

    The organic static induction transistor (OSIT) fabricated with organic semiconductor material copper-phthalocyanine(CuPc)is discussed in the paper. It has Schottky Gate electrode and sandwich structure of Au/CuPc/Al/CuPc/Au/glass. The operation mechanism of the device is studied on the physical model with practical parameters. Potential distribution and field intensity distribution in the conduction channel are computed by using finite-element method. By processing static experimental data with some mathematic tools,the V- I expression of CuPc/Al Schottky Gate is obtained and it is verified that OSIT has insaturation current property along with the increase of Drain bias voltage. By using AC small signal circuit model and appropriate numerical simulation method, the dynamic operating characteristics are investigated, and some influenced factors are analyzed.

  20. Operational Modal Analysis of Large Bridges

    OpenAIRE

    Schanke, Sindre Aavik

    2015-01-01

    As a part of the new coastal highway E39 which is being planned and built along the west coast of Norway by the Norwegian Public Roads Administration, state of the art methods of structural dynamics needs to be developed and used to cross the deep and wide fjords. Operational modal analysis aims to find the modal properties; natural frequencies, damping ratios and mode shapes of a structure while it is under operating conditions using its vibration data. Several methods of operati...

  1. 渔船氨水吸收式制冷系统的建模和理论运行特性分析%Simulation and theoretical operation characteristics analysis of ammonia-water absorption refrigeration system for fishing boat

    Institute of Scientific and Technical Information of China (English)

    倪锦; 顾锦鸿; 沈建

    2012-01-01

    根据渔船节能减排的需求,设计了一种新型的渔船氨水吸收式制冷系统,利用渔船余热实现渔船的制冰、蓄冷和工作区域供冷,解决了渔船上鱼类的保鲜和冷藏,改善船上工作环境.建立了渔船氨水吸收式制冷的热力学模型和性能评价指标,在此基础上采用序贯模块法迭代求解,实现了渔船氨水吸收式制冷系统的仿真,同时进一步研究了不同操作条件下制冷系统的运行特性,最终获得了烟气温度、流量和三通阀开度等参数变化时各用户端功率的变化规律.该系统模型可指导渔船制冷系统的功率分配,为优化渔船制冷系统的运行参数、实现低碳渔船提供理论基础.%A new type of fishing boat ammonia-water absorption refrigeration system considering the characteristics of fishing boat was designed.It drove by exhaust gas from the fishing boat's engine,it could realize ice-making,cool storage and environment cooling,the fishing boat refrigeration system could not only serve for fish cold storage and fish fresh-keeping,but also serve for fishing boat's environment cooling.The thermodynamic mathematical model and evaluation index for fishing boat ammonia-water absorption refrigeration system were established,the sequential modular approach was applied to solving ammonia-water absorption refrigeration system,so the simulation of ammonia-water absorption refrigeration system for fishing boat was realized.The refrigeration system's operation characteristics under different gas parameters and different three-way valve's operating conditions were investigated,Results shown that the system's operation characteristics could not only give fishing boat refrigeration system's power assignment,but also lay theoretical foundation for fishing boat refrigeration system's operation optimization and low carbon emission fishing boat.

  2. Operational modal analysis with non stationnary inputs

    OpenAIRE

    Gouache, Thibault; Morlier, Joseph; Michon, Guilhem; Coulange, Baptiste

    2013-01-01

    Operational modal analysis (OMA) techniques enable the use of in-situ and uncontrolled vibrations to be used to lead modal analysis of structures. In reality operational vibrations are a combination of numerous excitations sources that are much more complex than a random white noise or a harmonic. Numerous OMA techniques exist like SSI, NExT, FDD and BSS. All these methods are based on the fundamental hypothesis that the input or force applied to the structure to be analyzed is a stationary w...

  3. Analysis of Operating Characteristics of Hybrid Ground Source Heat Pump Assisted with Chiller%冷机辅助复合式地源热泵运行特性探析

    Institute of Scientific and Technical Information of China (English)

    周世玉; 崔文智

    2015-01-01

    Hybrid ground source heat pump system assisted with chiller is proposed in this paper, and also two kinds of operation scheme. System operation of 30 years is simulated using TRNSYS software. Compared with conventional ground source heat pump system, operating characteristics and the feasibility of the hybrid ground source heat pump system are analyzed from the ground temperature increase, system performance, energy consumption and also the technical and economic aspects.%提出了冷水机组和热泵机组分设的复合式地源热泵系统,并提出了两种运行方案。采用 TRNSYS软件模拟其30年的系统运行,并分别从地温增幅、系统性能、能耗及技术经济角度和常规地源热泵系统进行比较,分析了该复合式地源热泵系统的运行特性及其可行性。

  4. Analysis of Wind Power Output Characteristics and Its Impact on Operation of Power System%风电出力特性及其对电力系统运行的影响分析

    Institute of Scientific and Technical Information of China (English)

    杨林; 杨修宇; 涂娇娇; 聂昕; 高晓峰; 肖白

    2014-01-01

    In addition to water, wind power is public recognized as the most potential renewable energy. Although the rapid development of wind power solves the problem of energy shortage, it also causes some effects on power grid at the same time. Based on the wind power base in western Jilin province, this paper analyzed the effects on power system operation caused by the output characteristics of wind farms. According to the historical wind power output of this region in 2011, fluctuations, the probability distribution of the change rate, distribution, season characteristics and daily characteristics of wind power output were analyzed. The effect of characteristics of wind power output on frequency regulation, peak regulation and stabilization of power grid as well as the accommodating of wind power were studied, and suggestions and measures for corresponding problems were given.%风能被公认为除水能外最具发展前景的可再生能源,风电的快速发展在解决能源短缺的同时,也给电网带来了诸多影响。以吉林西部风电基地为背景,分析风电场群出力特性对电力系统运行的影响。根据2011年该地区实测的风电出力数据,分析风电出力的波动性、出力变化率的概率分布、出力分布、季节特性、日特性等,研究该地区风电场群出力特性对电网的调峰、调频、稳定性及风电消纳的影响,并针对相关问题给出相应建议与措施。

  5. Staffing for Cyberspace Operations: Summary of Analysis

    Science.gov (United States)

    2016-08-01

    information , including suggestions for reducing the burden, to Department of Defense, Washington Headquarters Services , Directorate for Information Operations...Analysis and Integration , Office of the Secretary of Defense Cost Assessment and Program Evaluation; and the Director, Acquisition Resources and...findings and recommendations of a full-length report containing classified information .1 It is meant to make the key elements of the analysis accessible

  6. 14 CFR 27.939 - Turbine engine operating characteristics.

    Science.gov (United States)

    2010-01-01

    ... drive system associated with critical combinations of power, rotational speed, and control displacement... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 27... of airflow distortion during normal operation, cause vibration harmful to the engine. (c) For...

  7. 14 CFR 29.939 - Turbine engine operating characteristics.

    Science.gov (United States)

    2010-01-01

    ... drive system associated with critical combinations of power, rotational speed, and control displacement... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 29... of airflow distortion during normal operation, cause vibration harmful to the engine. (c) For...

  8. Framework for the analysis of crystallization operations

    DEFF Research Database (Denmark)

    Meisler, Kresten Troelstrup; Abdul Samad, Noor Asma Fazli Bin; Gernaey, Krist

    Crystallization is often applied in the production of salts and/oractive pharmaceutical ingredients (API), and the crystallization step is an essential part of the manufacturing process for many chemicals-based products.In recent years the monitoring and analysis of crystallization operations has...

  9. Army Information Operations Officer Needs Analysis Report

    Science.gov (United States)

    2016-03-01

    helping with formatting the final report iv ARMY INFORMATION OPERATIONS OFFICER NEEDS ANALYSIS REPORT EXECUTIVE SUMMARY Research...time.” One IO officer suggested the IPO try to get a access the database that has all the old APA reports archived as a way to look at assessment

  10. Operational characteristics optimization of human-computer system

    OpenAIRE

    Zulquernain Mallick; Irfan Anjum Badruddin magami; Khaleed Hussain Tandur

    2010-01-01

    Computer operational parameters are having vital influence on the operators efficiency from readability viewpoint. Four parameters namely font, text/background color, viewing angle and viewing distance are analyzed. The text reading task, in the form of English text, was presented on the computer screen to the participating subjects and their performance, measured in terms of number of words read per minute (NWRPM), was recorded. For the purpose of optimization, the Taguchi method is u...

  11. Cepstrum analysis of seismic source characteristics

    Institute of Scientific and Technical Information of China (English)

    魏富胜; 黎明

    2003-01-01

    This paper introduces the concept of cepstrum. By investigating the difference in source characteristics between earthquakes and explosions the paper infers the manifestation of source difference in various variable domains, and seeks for effective means to express such source difference. Extending the approach of source discrimination from time and frequency domain to the cepstrum domain, the paper proposes a method of cepstrum analysis for recognizing the characteristics of seismic sources and establishes criteria for identifying the type of seismic sources. Cepstrum analysis on some recent earthquakes and explosions has been made, and the result shows that the method is quite effective in practice.

  12. 1000 kV 交流特高压输电线路运行特性分析%Analysis of 1 000 kV AC Ultra High Voltage Power Transmission Line Operation Characteristics

    Institute of Scientific and Technical Information of China (English)

    曹旭佳

    2015-01-01

    1000 kV 交流特高压输电线路是解决我国电力能源分布不均匀,降低电力负荷的有效手段。1000 kV 交流特高压线路的维护工作也开始受到社会各界的广泛关注。为了保障交流特高压线路能够安全运行,文章分析了1000 kV 交流特高压输电线路运行特性,借鉴了国外先进经验,总结了其中的关键技术。%1 000 kV AC UHV transmission line is an effective means of uneven distribution of electric energy,reduce the power load solutions,the maintenance work of 1 000 kV AC UHV line has begun to attract widespread concern in the community,in order to protect AC UHV safe operation,we must summarize the key technologies,learn from foreign ad-vanced experience,this paper analyzes the operating characteristics of 1 000 kV UHV AC transmission lines.

  13. 干式排渣在大型电站锅炉上的运行特性分析%Operating Characteristic Analysis of Dry Bottom Ash Handling System on Power Station Boiler

    Institute of Scientific and Technical Information of China (English)

    董信光; 李洪涛; 冷成岗; 李德功

    2012-01-01

    Comparing to the discharging slag by water, the dry bottom ash handling system has many advantages such as simple structure, water conserving, more useful. When the bottom ash system has been changed from water mode to dry mode, the operating characteristics of boiler will be varied, which is analyzed and optimized in detailed. Positive and negative impacts are found, which can be referred when the bottom ash system revised and boiler operating.%和水力除渣方式相比,干式排渣有结构简单、节水、干渣经济价值高等优点。将原水力除渣改为干式排渣后,锅炉的运行特性会发生变化,通过对干式排渣运行特性的全面分析和优化,找出积极因素和负面影响,为除渣系统的改造和运行提供参考。

  14. An investigation of the acoustic characteristics of a compression ignition engine operating with biodiesel blends

    Science.gov (United States)

    Zhen, D.; Tesfa, B.; Yuan, X.; Wang, R.; Gu, F.; Ball, A. D.

    2012-05-01

    In this paper, an experimental investigation has been carried out on the acoustic characteristics of a compression ignition (CI) engine running with biodiesel blends under steady state operating conditions. The experiment was conducted on a four-cylinder, four-stroke, direct injection and turbocharged diesel engine which runs with biodiesel (B50 and B100) and pure diesel. The signals of acoustic, vibration and in-cylinder pressure were measured during the experiment. To correlate the combustion process and the acoustic characteristics, both phenomena have been investigated. The acoustic analysis resulted in the sound level being increased with increasing of engine loads and speeds as well as the sound characteristics being closely correlated to the combustion process. However, acoustic signals are highly sensitive to the ambient conditions and intrusive background noise. Therefore, the spectral subtraction was employed to minimize the effects of background noise in order to enhance the signal to noise ratio. In addition, the acoustic characteristics of CI engine running with different fuels (biodiesel blends and diesel) was analysed for comparison. The results show that the sound energy level of acoustic signals is slightly higher when the engine fuelled by biodiesel and its blends than that of fuelled by normal diesel. Hence, the acoustic characteristics of the CI engine will have useful information for engine condition monitoring and fuel content estimation.

  15. Operational amplifier circuits analysis and design

    CERN Document Server

    Nelson, J C C

    1995-01-01

    This book, a revised and updated version of the author's Basic Operational Amplifiers (Butterworths 1986), enables the non-specialist to make effective use of readily available integrated circuit operational amplifiers for a range of applications, including instrumentation, signal generation and processing.It is assumed the reader has a background in the basic techniques of circuit analysis, particularly the use of j notation for reactive circuits, with a corresponding level of mathematical ability. The underlying theory is explained with sufficient but not excessive, detail. A range of compu

  16. Victim countries of transnational terrorism: an empirical characteristics analysis.

    Science.gov (United States)

    Elbakidze, Levan; Jin, Yanhong

    2012-12-01

    This study empirically investigates the association between country-level socioeconomic characteristics and risk of being victimized in transnational terrorism events. We find that a country's annual financial contribution to the U.N. general operating budget has a positive association with the frequency of being victimized in transnational terrorism events. In addition, per capita GDP, political freedom, and openness to trade are nonlinearly related to the frequency of being victimized in transnational terrorism events. © 2012 Society for Risk Analysis.

  17. Operating characteristics of isocaloric fountain-effect pumps

    Science.gov (United States)

    Kittel, Peter

    1988-01-01

    The governing equations of thermomechanical (fountain-effect) pumps are usually given for pumps operating at a constant temperature difference. These are the thermomechanical and mechanocaloric effects in which the pressure head and mass flow are independent of each other. Here, these equations are recast for a pump operating at a constant heat input (isocaloric). This form more closely represents how such pumps are likely to be used. Under these conditions, the pressure head and mass flow are shown to be related. For ideal pumps, the head and flow are related by a universal curve. For real pumps (those that have normal fluid leakage), a family of curves is developed. These curves approach the curve for an ideal pump at high flow rates. The isocaloric equations are also extended to multistage pumps.

  18. Refrigerating machine operating characteristics under various mixed refrigerant mass charges

    Energy Technology Data Exchange (ETDEWEB)

    Rozhentsev, Andrey [Far Eastern State Transport University of the Russian Federation, Seryshev street, 47, 680021 Khabarovsk (Russian Federation)

    2008-11-15

    This paper reports the results of experimental investigation of a low-temperature Joule-Thomson refrigerating machine, working by use of a non-azeotropic mixture of refrigerants and with a single-stage hermetic compressor. The temperature, hydraulic and power performance of the machine are determined experimentally in relation to the mixed refrigerant (MR) mass charge. Variations of the MR refrigerating machine operating performance with the working mixture mass charge are found to be considerably different from the analogous performance variations of a refrigerating machine charged with a pure refrigerant. The peculiarities of those relationships are analyzed theoretically. The specific value of a minimum acceptable MR mass charge for the investigated system and its correlation with internal processes in the machine loop are established as well. If the refrigerant mixture mass charges are below the minimum ones, the temperature and power performance of the MR machine differ essentially from the design performance and such operating modes are considered inadmissible. (author)

  19. Studying the operation characteristics and structure of vertical channel copper-phthalocyanine organic semiconductor transistor

    Institute of Scientific and Technical Information of China (English)

    ZHU Min; SONG Ming-xin; GUI Tai-long; WANG Xuan; YIN Jing-hua; WANG Dong-xing; ZHAO Hong

    2005-01-01

    The creation of Au/CuPc/Al/CuPc/structure is a perpendicular type electricity found in the channel of organic static induction transistor. In the following we analyze transistor operation characteristics and machine structural relation. The results express that the transistor drives the voltage low and has no-saturation currentvoltage characteristics. Its operation characteristics are dependant on gate bias voltage and the construction of the aluminum electrode.The vertical channel of organic static induction transistor (OSIT) , with structure of Au/CuPc/Al/CuPc/Cu, has been determined. According to the test results, the relation of its operation characteristics and device structure was analyzed. The results show that this transistor has a low driving voltage and unsaturation Ⅰ-Ⅴ characteristics. Its operation characteristics are dependant on gate bias voltage and the structure of the aluminum electrode.

  20. Process Analysis of the CV Group's Operation

    CERN Document Server

    Wilhelmsson, M

    2000-01-01

    This report will give an explanation of the internal reorganization that has been done because of the necessity to optimize operation in the cooling and ventilation group. The basic structure for the group was defined at the end of 1998. We understood then that change was needed to accommodate the increased workload due to the LHC project. In addition, we face a relatively large turnover of personnel (retirements and some recruitment) with related integration issues to consider. We would also like to implement new approaches in the management of both operations and maintenance. After some running-in problems during the first half of 1999, we realized that much more could be gained with the analysis and the definition and documenting of each single function and generic activity within the group. The authors will explain how this analysis was carried out and give some feedback of the outcome, so far.

  1. Functional analysis and the Feynman operator calculus

    CERN Document Server

    Gill, Tepper L

    2016-01-01

    This book provides the mathematical foundations for Feynman's operator calculus and for the Feynman path integral formulation of quantum mechanics as a natural extension of analysis and functional analysis to the infinite-dimensional setting. In one application, the results are used to prove the last two remaining conjectures of Freeman Dyson for quantum electrodynamics. In another application, the results are used to unify methods and weaken domain requirements for non-autonomous evolution equations. Other applications include a general theory of Lebesgue measure on Banach spaces with a Schauder basis and a new approach to the structure theory of operators on uniformly convex Banach spaces. This book is intended for advanced graduate students and researchers.

  2. Some Elements of Operational Modal Analysis

    OpenAIRE

    Rune Brincker

    2014-01-01

    This paper gives an overview of the main components of operational modal analysis (OMA) and can serve as a tutorial for research oriented OMA applications. The paper gives a short introduction to the modeling of random responses and to the transforms often used in OMA such as the Fourier series, the Fourier integral, the Laplace transform, and the Z-transform. Then the paper introduces the spectral density matrix of the random responses and presents the theoretical solutions for correlation f...

  3. Staffing for Cyberspace Operations: Summary of Analysis

    Science.gov (United States)

    2016-08-01

    Service’s current mix with the IDA alternative). The costing was performed in accordance with guidance and cost elements laid out in DoDI 7041.04.5 The...capable of carrying out cyberspace operations is currently a major force planning effort in the Department of Defense (DoD). Determining the...Analysis and Integration, Office of the Secretary of Defense Cost Assessment and Program Evaluation; and the Director, Acquisition Resources and

  4. Therapy Operating Characteristic (TOC) Curves and their Application to the Evaluation of Segmentation Algorithms.

    Science.gov (United States)

    Barrett, Harrison H; Wilson, Donald W; Kupinski, Matthew A; Aguwa, Kasarachi; Ewell, Lars; Hunter, Robert; Müller, Stefan

    2010-01-01

    This paper presents a general framework for assessing imaging systems and image-analysis methods on the basis of therapeutic rather than diagnostic efficacy. By analogy to receiver operating characteristic (ROC) curves, it utilizes the Therapy Operating Characteristic or TOC curve, which is a plot of the probability of tumor control vs. the probability of normal-tissue complications as the overall level of a radiotherapy treatment beam is varied. The proposed figure of merit is the area under the TOC, denoted AUTOC. If the treatment planning algorithm is held constant, AUTOC is a metric for the imaging and image-analysis components, and in particular for segmentation algorithms that are used to delineate tumors and normal tissues. On the other hand, for a given set of segmented images, AUTOC can also be used as a metric for the treatment plan itself. A general mathematical theory of TOC and AUTOC is presented and then specialized to segmentation problems. Practical approaches to implementation of the theory in both simulation and clinical studies are presented. The method is illustrated with a a brief study of segmentation methods for prostate cancer.

  5. An Analysis of Skill Requirements for Operators of Amphibious Air Cushion Vehicles (ACVs).

    Science.gov (United States)

    McKnight, A. James; And Others

    This report describes the skills required in the operation of an amphibious air cushion vehicle (ACV) in Army tactical and logistic missions. The research involved analyzing ACV characteristics, operating requirements, environmental effects, and results of a simulation experiment. The analysis indicates that ACV operation is complicated by an…

  6. An Analysis of Skill Requirements for Operators of Amphibious Air Cushion Vehicles (ACVs).

    Science.gov (United States)

    McKnight, A. James; And Others

    This report describes the skills required in the operation of an amphibious air cushion vehicle (ACV) in Army tactical and logistic missions. The research involved analyzing ACV characteristics, operating requirements, environmental effects, and results of a simulation experiment. The analysis indicates that ACV operation is complicated by an…

  7. Operational Characteristics Identification and Simulation Model Verification for Incheon International Airport

    Science.gov (United States)

    Eun, Yeonju; Jeon, Daekeun; Lee, Hanbong; Zhu, Zhifan; Jung, Yoon C.; Jeong, Myeongsook; Kim, Hyounkyong; Oh, Eunmi; Hong, Sungkwon; Lee, Junwon

    2016-01-01

    integrated into NASA's Airspace Technology Demonstration-2 (ATD-2) project for technology demonstration of Integrated Arrival-Departure-Surface (IADS) operations at CLT. This study is a part of the international research collaboration between KAIA (Korea Agency for Infrastructure Technology Advancement), KARI (Korea Aerospace Research Institute) and NASA, which is being conducted to validate the effectiveness of SARDA concept as a controller decision support tool for departure and surface management of ICN. This paper presents the preliminary results of the collaboration effort. It includes investigation of the operational environment of ICN, data analysis for identification of the operational characteristics of the airport, construction and verification of airport simulation model using Surface Operations Simulator and Scheduler (SOSS), NASA's fast-time simulation tool.

  8. INDIVIDUAL PSYCHOLOGICAL CHARACTERISTICS OF RAILWAYS OPERATORS OF DIFFERENT AGE GROUPS

    Directory of Open Access Journals (Sweden)

    Bugaeva V. M.

    2015-10-01

    Full Text Available The article presents the results of the study of some individual psychological characteristics of the drivers of rail transport in the age groups 25–34 and 35–45 years. We have identified a number of differences between the two age groups associated with both features individually-psychological sphere, and in the psycho-physiological features. Features of age-related psychological differences can be explained by the age characteristics of the representatives of each group; psycho-physiological features of age differences may reflect developed in the course of a long professional activity features. We have also developed adaptive strategies, consciously or unconsciously selected during the long-running monotonous activities and in small social groups (teams of drivers allow, on the one hand, higher quality performance of their professional duties, on the other — to avoid the harmful effects of stressful situations at work. It can be assumed that the composition of drivers age group 35– 45 years is the result of natural selection, when those who did not cope with this type of activity is simply dismissed or transferred to other kinds of professions

  9. 老年拔牙手术患者的焦虑与疼痛特征研究%Analysis of the characteristics of anxiety and pain of the elderly patients undergoing tooth extraction operation

    Institute of Scientific and Technical Information of China (English)

    贾皖宁; 扈祚文; 钟文; 汪峰

    2015-01-01

    Objective To study the the characteristics of anxiety and pain of the elderly patients undergoing tooth extraction operation.Methods Eighty elderly patients(elderly group) underwent tooth extraction operation,including 53 males and 27 females,aged from 60 to 85 years,with a mean age of 71.8±8.4 years.While 80 non-elderly patients undergoing tooth extraction operation,including 32 males and 48 females,aged from 14 to 35 years,with a mean age of 24.6± 6.9 years,were enrolled as the controls.The modified dental anxiety scale was used to assess the levels of anxiety.The levels of chewing pain and biting pain of the patients were evaluated by applying Visual Analogue Rating Scale.The data were analyzed and compared between the two groups.Moreover,according to the degrees of anxiety the elderly group was divided into three subgroups:mild anxiety subgroup,moderate anxiety subgroup and severe anxiety subgroup.The relationship between anxiety and pain was analyzed.Results Before tooth extraction operation,compared with the control group,the percentage of severe anxiety and mild anxiety in elderly group were significantly increased (P<0.01).After the tooth extraction operation for 1 day and 2 days,the levels of chewing pain and biting pain were significantly increased in elderly group than those in control group (P<0.05 or P<0.01).After the tooth extraction operation for 1 day,compared with the mild anxiety subgroup,the levels of chewing pain and biting pain in the severe anxiety subgroup and moderate anxiety subgroup were significantly increased (P<0.05 or P<0.01).The levels of chewing pain and biting pain in the severe anxiety subgroup were significantly higher than those of the moderate anxiety subgroup (P<0.05).Conclusions The levels of chewing pain and biting pain in elderly patients after tooth extraction operation are more obviously.Paying attention to the characteristics of anxiety and pain may be of benefit to dental surgery in elderly patients

  10. Operational morbidity analysis of soft tissue injuries during Operation TELIC.

    Science.gov (United States)

    Ollerton, J; Hodgetts, T; Russell, R

    2007-12-01

    Soft tissue injury accounted for one in five of all presentations to the Emergency Department (ED) during Operation TELIC (UK forces in Iraq) from March 2003 to November 2006. This ranks soft tissue complaints as the most frequent cause of attendance to a deployed field hospital ED. This paper analyses the injury patterns, together with implications for future clinical practice and operational planning to prevent injury, optimise patient care and maximize force regeneration.

  11. Analysis for the Dynamic Characteristic of the Automobile Transmission Gearbox

    Directory of Open Access Journals (Sweden)

    Fujin Yu

    2013-02-01

    Full Text Available Automobile transmission gearbox, as one of the major components, which will inevitably bring about the vibration and noise of automobile vehicle. The objective of this study to reduce the noise and vibration of automobile transmission by structural optimization of the gearbox in order to better control its functional operation and improve its performance. For this purpose, based on the working characteristics of the gearbox, modal analysis of automobile transmission gearbox is formulated using 3D graphics software Pro/E together with Finite Element Method. In addition, the modal test of gearbox is conducted also. Through comparing model analysis results to test results, test results verify the correctness of the finite element analysis results, thus provide the theoretic basis to analyze its dynamic characteristics of the gearbox structure as well as its improvement to reduce vibration and noise.

  12. Operational Analysis in the Launch Environment

    Science.gov (United States)

    James, George; Kaouk, Mo; Cao, Tim; Fogt, Vince; Rocha, Rodney; Schultz, Ken; Tucker, Jon-Michael; Rayos, Eli; Bell,Jeff; Alldredge, David; Howsman, Tom

    2012-01-01

    The launch environment is a challenging regime to work due to changing system dynamics, changing environmental loading, joint compression loads that cannot be easily applied on the ground, and control effects. Operational testing is one of the few feasible approaches to capture system level dynamics since ground testing cannot reproduce all of these conditions easily. However, the most successful applications of Operational Modal Testing involve systems with good stationarity and long data acquisition times. This paper covers an ongoing effort to understand the launch environment and the utility of current operational modal tools. This work is expected to produce a collection of operational tools that can be applied to non-stationary launch environment, experience dealing with launch data, and an expanding database of flight parameters such as damping. This paper reports on recent efforts to build a software framework for the data processing utilizing existing and specialty tools; understand the limits of current tools; assess a wider variety of current tools; and expand the experience with additional datasets as well as to begin to address issues raised in earlier launch analysis studies.

  13. Analysis of Operational Risks in Shipbuilding Industry

    Directory of Open Access Journals (Sweden)

    Daniela MATEI

    2012-11-01

    Full Text Available Our paper emphasizes the opportunities provided both for the academic research and companies by using a proposed model of analyzing the operational risks within business in general and shipbuilding industry in particular. The model aims to display the loss distribution from the operational risk for each business line/ type of event, based on frequency and severity estimation of the events. These estimations are derived mainly from the history logs of internal loss events. The calculations extend over a certain period of time in the future with a certain level of confidence. It should also be mentioned that the proposed model estimates unexpected losses, without making any suppositions concerning the values of the expected and unexpected losses. Several ideas could be extracted by analyzing and synthesizing the theoretical models from available literature. These ideas were analyzed in order to develop a model for operational risk analysis that is adapted to shipbuilding. This paper describes a new model, which can be applied to the naval industry to quantify operational risks.

  14. WIND TURBINE OPERATION PARAMETER CHARACTERISTICS AT A GIVEN WIND SPEED

    Directory of Open Access Journals (Sweden)

    Zdzisław Kamiński

    2014-06-01

    Full Text Available This paper discusses the results of the CFD simulation of the flow around Vertical Axis Wind Turbine rotor. The examined rotor was designed following patent application no. 402214. The turbine operation is characterised by parameters, such as opening angle of blades, power, torque, rotational velocity at a given wind velocity. Those parameters have an impact on the performance of entire assembly. The distribution of forces acting on the working surfaces in the turbine can change, depending on the angle of rotor rotation. Moreover, the resultant force derived from the force acting on the oncoming and leaving blades should be as high as possible. Accordingly, those parameters were individually simulated over time for each blade in three complete rotations. The attempts to improve the performance of the entire system resulted in a new research trend to improve the performance of working turbine rotor blades.

  15. Operational analysis of open-cycle MHD

    Science.gov (United States)

    Lippert, T. E.; McCutchan, D. A.

    1980-07-01

    Open cycle magnetohydrodynamic (OCMHD) conceptual power plant designs are studied in the context of a utility system to form a better basis for understanding their design, design requirements, and market possibilities. Based on assumed or projected plant costs and performance characteristics, assumed economics and escalation factors, and one coal supply and delivery scenario, overall and regional OCMHD utility market possibilities are reviewed. Additionally, for one hypothetical utility system a generation expansion plan is developed that includes OCMHD as a baseload power generating station. The impact on generation system economics and operation of alternating selected MHD plant cost and performance characteristics is reviewed. Baseload plant availability is shown as an important plant design consideration, and a general methodology and data base is developed to assess the impact on design and cost of various reliability decisions. An overall plant availability goal is set and the required availabilities of various MHD high technology components are derived to meet the plant goal. The approach is then extended to projecting channel life goals for various plant design configurations and assumptions.

  16. 保险金融综合经营共生界面特征的计量分析%Analysis on the Model of the Characteristics of Insurance Finance Comprehensive Operation Symbiasis Inter~ace

    Institute of Scientific and Technical Information of China (English)

    易志刚; 易中懿

    2012-01-01

    关于保险金融集团综合经营模式共生界面特征的计量研究,既为保险金融集团综合经营共生界面业务单元选择及组合方式提供依据,也为保险金融集团综合经营模式优化完善提供理论性策略。构建了保险金融集团综合经营模式的共生界面特征参数体系及数学分析模型,创新性地提出共生界面的能量效率分配的相对临界系数和绝对临界系数。研究了共生界面特征参数的量化计算方法,形成了基于共生理论对共生界面特征量化研究的理论基础。%The research of symbiotic interface characteristics of insurance & financial group diverse economic undertakings by econometric model, not only provided evidence for the selection of the insurance & financial business units in its symbiosis interface, also for provided the policy proposal to the insurance financial group diverse economic undertakings mode of the optimization in its symbiotic interface. This paper builded up the insurance & financial group integrated and put innovatively out lute critical coefficient. business model of symbiosis interface characteristics parameters system and analysis model, symbiosis of energy efficiency of distribution interface relative critical coefficient and absolute critical coefficient.

  17. Analysis and Realization of the Test Method of Operating Characteristic with Load for Residual-current Circuit Breaker%漏电断路器带载动作特性试验方法分析及实现

    Institute of Scientific and Technical Information of China (English)

    林承志; 陈金汕; 张业真

    2015-01-01

    文章依据国家标准,介绍了电子式漏电断路器利用漏电开关兼容试验装置进行带负载剩余电流动作特性的试验方法,验证其动作正确性。试验有时会发生试验样品烧毁的问题,分析出现问题的原因并设计出一个智能检测模块,在电子式漏电断路器脱扣后可快速切断检测设备的试验电源,经过了实际调试运行,解决了试验样品烧毁问题,对该项试验的检测工作具有重要的意义。%According to the national standard, this paper takes research on the test method which would cause burning down the test samples sometimes, the method that RCBO is operating characteristic under residual current with load with the leakage switch compatibility test equipment. This paper analyzes the reason of the problem, then designs a intelligent detection module, in order to rapid cutting off the power supply of equipment after the electronic type RCBO tripping. Through the actual debugging, it can solve the problem of the test sample burned. It is very important to the testing work of the project.

  18. System of Systems Operational Analysis Within a Common Operational Context

    Science.gov (United States)

    2005-06-22

    detection UNCLASSIFIED • The use of the Advanced Refractive Effects Prediction System (AREPS) produced by SPAWAR provides the effects of specific radar ...parameters to build the characteristic AEW or interceptor radar • Provides Probability of Detection vs. Range plots • Import into MATLAB to curve-fit...for later use Sensor Information from AREPS UNCLASSIFIED Sensor Information from AREPS Example AREPS Pd vs. Range raytrace output Elevated Sensor

  19. Plasma physics analysis of SERT-2 operation

    Science.gov (United States)

    Kaufman, H. R.

    1980-01-01

    An analysis of the major plasma processes involved in the SERT 2 spacecraft experiments was conducted to aid in the interpretation of recent data. A plume penetration model was developed for neutralization electron conduction to the ion beam and showed qualitative agreement with flight data. In the SERT 2 configuration conduction of neutralization electrons between thrusters was experimentally demonstrated in space. The analysis of this configuration suggests that the relative orientation of the two magnetic fields was an important factor in the observed results. Specifically, the opposed field orientation appeared to provide a high conductivity channel between thrusters and a barrier to the ambient low energy electrons in space. The SERT 2 neutralizer currents with negative neutralizer biases were up to about twice the theoretical prediction for electron collection by the ground screen. An explanation for the higher experimental values was a possible conductive path from the neutralizer plume to a nearby part of the ground screen. Plasma probe measurements of SERT 2 gave the clearest indication of plasma electron temperature, with normal operation being near 5 eV and discharge only operation near 2 eV.

  20. STATIC CONVERTERS OF THE ELECTRIC POWER WITH IMPROVED OPERATION-TECHNICAL CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    Uskov A. E.

    2014-03-01

    Full Text Available The article describes scopes and new technical decisions of static converters of the electric power with the improved operation-characteristics, executed with use of new element base and a modular principle of construction

  1. Modeling the effect of operator and passenger characteristics on the fatality risk of motorcycle crashes

    Directory of Open Access Journals (Sweden)

    Ali Tavakoli Kashani

    2016-01-01

    Full Text Available BACKGROUND:In Iran more than 25% of crash fatalities belong to motorcycle operators and passengers in the recent years, from which about 20% are related to passenger fatalities. METHODS: The aim of this study was to investigate the motorcycle operator and passenger characteristics as well as other contributory factors that may affect the fatality risk of motorcyclists involved in traffic crashes. To this end, motorcycle crash data between 2009 and 2012 was extracted from Iran traffic crash database and a logistic regression analysis was performed to obtain odds ratio estimates for each of the study variables. RESULTS: The fatality risk of motorcyclists has a direct relationship with the number of pillion passengers carried. Results also indicate that the amount of increase in the likelihood of having a fatality in a motorcycles crash is considerably higher when the operator is accompanied by a male passenger of the same age. Furthermore, results showed that if the crash is occurred in the darkness, on curves, in rural areas and on highways, then the crash would be more likely to be fatal. Moreover, the head-on collisions, older operators, unlicensed operators and not using a safety helmet were found to increase the likelihood of a fatality in a motorcycle crash. CONCLUSIONS: Preventative measures such as, imposing stricter rules regarding safety helmet usage and confining the number of pillion passengers to one, might be implemented to reduce the fatality risk in motorcycle crashes. In addition, more appropriate infrastructures for penalizing offending motorcyclists could also reduce the frequency of law violations such as not wearing helmet or riding without motorcycle license, which in turn, would result into a reduction in the fatality risk of motorcycle crashes

  2. 运行参数对微型内燃机微燃烧特性影响机理分析%Effect mechanism analysis of operation parameters on micro combustion characteristics in micro IC engines

    Institute of Scientific and Technical Information of China (English)

    唐刚志; 张力; 尚会超; 杜宝程

    2015-01-01

    Micro combustion process of micro IC engine is very sensitive to changes of equivalent ratio and speed.The laminar flow finite rate model and methanol chemical reaction mechanism is adopted to simulation its premixed laminar combustion process.And then,the influence law of equivalent ratio and speed on micro combustion characteristic is explored, and the critical operation parameters are investigated.Finally,the thermal ignition theory and chemical reaction kinetics theory is adopted to explore the influence of equivalent ratio on micro combustion characteristic mechanism.The results show that simulation results agree well with experiment.When equivalent ratio increases from 0.6 to 1.1,the combustion rate,the pressure and the temperature increase,pressure peak increases by about 1.5E+6 Pa and the maximum temperature increases by about 1 300 K.Since then,with the increase of ratio equivalent,the combustion rate,the pressure and the temperature also reduce.Moreover,the research reveals the mechanism that equivalent ratio affects micro combustion characteristic.In dilute zone, equivalent ratio mainly affects micro combustion performance by temperature changes.As equivalent ratio increases,fuel concentration and released heat increase,thus the temperature and the pressure increase, and then combustion ratio increases.In thick zone,equivalent ratio mainly affects micro combustion performance by oxygen changes.As equivalent ratio decreases,oxygen volume and reaction rate decrease, thus combustion ratio decreases,and then the temperature and the pressure decrease.When the speed lifts, the time for combustion is shortened,thus the complete combustion level reduces and the temperature and the pressure drop.Because of relatively large heat loss and short residence time of micro combustion,the complete combustion operation area of micro engine is narrow.The lean burn limit to realize complete combustion is about 0.9 in our experiments,and the highest speed is about 6 000 r

  3. Thermal-hydraulic characteristics of natural circulation operation for decay heat removal of LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Tomonari [Central Research Inst. of Electric Power Industry, Abiko, Chiba (Japan); Watanabe, Osamu [Advanced Reactor Technology Co., Ltd., Tokyo (Japan)

    2000-10-01

    Thermal-hydraulic characteristics of the decay heat removal system (DHRS) has been evaluated by both a water test and its computational analysis. The direct reactor auxiliary cooling system (DRACS) was studied as a representative DHRS in the LMFBR design. A natural circulation flow of the DRACS is originated from the buoyancy force balanced with the pressure loss within the active core. Hence it appears that the performance of the DRACS could be fully estimated by the thermal-hydraulic study of one fuel sub-assembly under the condition of low flow rate. The inter-wrapper flow occurring in the gap between core sub-assemblies under the natural circulation operation might have a large capacity to cool the core. An inverse flow occurring at the outer region of the core was due to the cooling effect of the inter-wrapper flow. (author)

  4. Optimal algorithm for automatic detection of microaneurysms based on receiver operating characteristic curve

    Science.gov (United States)

    Xu, Lili; Luo, Shuqian

    2010-11-01

    Microaneurysms (MAs) are the first manifestations of the diabetic retinopathy (DR) as well as an indicator for its progression. Their automatic detection plays a key role for both mass screening and monitoring and is therefore in the core of any system for computer-assisted diagnosis of DR. The algorithm basically comprises the following stages: candidate detection aiming at extracting the patterns possibly corresponding to MAs based on mathematical morphological black top hat, feature extraction to characterize these candidates, and classification based on support vector machine (SVM), to validate MAs. Feature vector and kernel function of SVM selection is very important to the algorithm. We use the receiver operating characteristic (ROC) curve to evaluate the distinguishing performance of different feature vectors and different kernel functions of SVM. The ROC analysis indicates the quadratic polynomial SVM with a combination of features as the input shows the best discriminating performance.

  5. Analysis of physical characteristics of vegetable oils

    Energy Technology Data Exchange (ETDEWEB)

    Piamba Tulcan, Oscar Edwin [Universidade Nacional da Colombia (UNAL), Bogota (Colombia). Fac. de Ingenieria; Universidade Federal Fluminense (PGMEC/UFF), Niteroi, RJ (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica], E-mail: oepiambat@unal.edu.co; Andrade, Danielle Oliveira de; Andrade, Ednilton Tavares de [Universidade Federal Fluminense (TER/UFF), Niteroi, RJ (Brazil). Dept. de Engenharia Agricola e do Meio Ambiente; Pereira, Roberto Guimaraes [Universidade Federal Fluminense (TER/UFF), Niteroi, RJ (Brazil). Dept. de Engenharia Mecanica

    2008-07-01

    Different vegetable oils were characterized using standardized methods. The evaluated characteristics were density, viscosity, flow point, cloud point and corrosion. The obtained data was tabulated and compared with average composition values of oils in percentage of fatty acids and iodine number for each oil. In this analysis it is shown that viscosity decreases with the increase of the iodine number, and density decrease. The cloud and flow point have greater relation with the presence of saturated or highly unsaturated fatty acids, respectively. The index of corrosion is greater when oil saturation or its iodine number are increased. (author)

  6. Buyer-focused operations as a supply chain strategy : Identifying the influence of business characteristics

    NARCIS (Netherlands)

    van der Vaart, T; van Donk, DP

    2006-01-01

    Purpose - Buyer-focused operations aim at a high level of supply chain alignment by singling out resources for one buyer in order to serve this buyer optimally. The purpose of this paper is to identify what business characteristics make suppliers choose buyer-focused operations as a supply chain

  7. Operating characteristics of a three-stage Stirling pulse tube cryocooler operating around 5 K

    Science.gov (United States)

    Qiu, L. M.; Cao, Q.; Zhi, X. Q.; Han, L.; Gan, Z. H.; Yu, Y. B.; Liu, Y.; Zhang, X. J.; Pfotenhauer, J. M.

    2012-07-01

    A Stirling pulse tube cryocooler (SPTC) operating at the liquid-helium temperatures represents an excellent prospect for satisfying the requirements of space applications because of its compactness, high efficiency and reliability. However, the working mechanism of a 4 K SPTC is more complicated than that of the Gifford McMahon (GM) PTC that operates at the relatively low frequency of 1-2 Hz, and has not yet been well understood. In this study, the primary operating parameters, including frequency, charge pressure, input power and precooling temperature, are systematically investigated in a home-developed separate three-stage SPTC. The investigation demonstrates that the frequency and precooling temperature are closely coupled via phase shift. In order to improve the cooling capacity it is important to lower the frequency and the precooling temperature simultaneously. In contrast to the behavior predicted by previous studies, the pressure dependence of the gas properties results in an optimized pressure that decreases significantly as the temperature is lowered. The third stage reaches a lowest temperature of 4.97 K at 29.9 Hz and 0.91 MPa. A cooling power of 25 mW is measured at 6.0 K. The precooling temperature is 23.7 K and the input power is 100 W.

  8. Operational modal analysis by updating autoregressive model

    Science.gov (United States)

    Vu, V. H.; Thomas, M.; Lakis, A. A.; Marcouiller, L.

    2011-04-01

    This paper presents improvements of a multivariable autoregressive (AR) model for applications in operational modal analysis considering simultaneously the temporal response data of multi-channel measurements. The parameters are estimated by using the least squares method via the implementation of the QR factorization. A new noise rate-based factor called the Noise rate Order Factor (NOF) is introduced for use in the effective selection of model order and noise rate estimation. For the selection of structural modes, an orderwise criterion called the Order Modal Assurance Criterion (OMAC) is used, based on the correlation of mode shapes computed from two successive orders. Specifically, the algorithm is updated with respect to model order from a small value to produce a cost-effective computation. Furthermore, the confidence intervals of each natural frequency, damping ratio and mode shapes are also computed and evaluated with respect to model order and noise rate. This method is thus very effective for identifying the modal parameters in case of ambient vibrations dealing with modern output-only modal analysis. Simulations and discussions on a steel plate structure are presented, and the experimental results show good agreement with the finite element analysis.

  9. Some Elements of Operational Modal Analysis

    Directory of Open Access Journals (Sweden)

    Rune Brincker

    2014-01-01

    Full Text Available This paper gives an overview of the main components of operational modal analysis (OMA and can serve as a tutorial for research oriented OMA applications. The paper gives a short introduction to the modeling of random responses and to the transforms often used in OMA such as the Fourier series, the Fourier integral, the Laplace transform, and the Z-transform. Then the paper introduces the spectral density matrix of the random responses and presents the theoretical solutions for correlation function and spectral density matrix under white noise loading. Some important guidelines for testing are mentioned and the most common techniques for signal processing of the operating signals are presented. The algorithms of some of the commonly used time domain and frequency domain identification techniques are presented and finally some issues are discussed such as mode shape scaling, and mode shape expansion. The different techniques are illustrated on the difficult case of identifying the three first closely spaced modes of the Heritage Court Tower building.

  10. EXPERIMENTAL STUDY OF EFFECTS OF OPERATING CONDITIONS ON THE FLOW CHARACTERISTICS OF WATER HYDRAULIC THROTTLE

    Institute of Scientific and Technical Information of China (English)

    Liu Yinshui; Nie Songlin; Zhu Yuquan; He Xiaofeng; Li Zhuangyun

    2004-01-01

    Experimental investigations are made on the effects of operating conditions on the flow characteristics of throttle when tap water is used as the working media. The researched throttles include cone poppet valve, ball valve, disc valve and dumping orifice. Operating condition includes poppet lift, working media, back pressure, medium temperature, etc. Because the vapourous pressure of water is much higher than that of oil, cavitation is easier to occur in water hydraulic elements and systems, so the effects of operating conditions on the cavitation characteristics of throttle are also researched.

  11. Operator Semigroups meet Complex Analysis, Harmonic Analysis and Mathematical Physics

    CERN Document Server

    Chill, Ralph; Tomilov, Yuri

    2015-01-01

    This proceedings volume originates from a conference held in Herrnhut in June 2013. It provides unique insights into the power of abstract methods and techniques in dealing successfully with numerous applications stemming from classical analysis and mathematical physics. The book features diverse topics in the area of operator semigroups, including partial differential equations, martingale and Hilbert transforms, Banach and von Neumann algebras, Schrödinger operators, maximal regularity and Fourier multipliers, interpolation, operator-theoretical problems (concerning generation, perturbation and dilation, for example), and various qualitative and quantitative Tauberian theorems with a focus on transfinite induction and magics of Cantor. The last fifteen years have seen the dawn of a new era for semigroup theory with the emphasis on applications of abstract results, often unexpected and far removed from traditional ones. The aim of the conference was to bring together prominent experts in the field of modern...

  12. Design of a receiver operating characteristic (ROC) study of 10:1 lossy image compression

    Science.gov (United States)

    Collins, Cary A.; Lane, David; Frank, Mark S.; Hardy, Michael E.; Haynor, David R.; Smith, Donald V.; Parker, James E.; Bender, Gregory N.; Kim, Yongmin

    1994-04-01

    The digital archiving system at Madigan Army Medical Center (MAMC) uses a 10:1 lossy data compression algorithm for most forms of computed radiography. A systematic study on the potential effect of lossy image compression on patient care has been initiated with a series of studies focused on specific diagnostic tasks. The studies are based upon the receiver operating characteristic (ROC) method of analysis for diagnostic systems. The null hypothesis is that observer performance with approximately 10:1 compressed and decompressed images is not different from using original, uncompressed images for detecting subtle pathologic findings seen on computed radiographs of bone, chest, or abdomen, when viewed on a high-resolution monitor. Our design involves collecting cases from eight pathologic categories. Truth is determined by committee using confirmatory studies performed during routine clinical practice whenever possible. Software has been developed to aid in case collection and to allow reading of the cases for the study using stand-alone Siemens Litebox workstations. Data analysis uses two methods, ROC analysis and free-response ROC (FROC) methods. This study will be one of the largest ROC/FROC studies of its kind and could benefit clinical radiology practice using PACS technology. The study design and results from a pilot FROC study are presented.

  13. V-Band Fade Dynamics Characteristics Analysis in Tropical Region

    Directory of Open Access Journals (Sweden)

    Khairayu Badron

    2010-01-01

    Full Text Available Problem statement: Satellite operations at V band in tropical and equatorial regions are constrained as a result of attenuation from rain. Approach: Statistics for 20 consecutive months of V band terrestrial link signal attenuation measurements in Malaysia were presented in this analysis. Such information was considered very pertinent for Earth-space communication link design and can be used for initial groundwork plan for the engineers as well as researchers. Results: The measured statistics were then fittingly scaled up to fit Earth-satellite link. The statistics were then broken down to examine diurnal variations. Characteristics of rain events such as fade duration and inter-fade interval were presented. Conclusion/Recommendations: It is essential to identify such characteristics for the design and implementation of future fade countermeasure techniques on satellite links.

  14. The characteristics of activities of the operator of a management system by the line for release of foodstuff

    Directory of Open Access Journals (Sweden)

    Al-Hetari H.M. Abdulaziz

    2016-01-01

    Full Text Available The article presents the analysis of the main stages of professional activity of the operator of a management system by a production line of food products. Studied the question of the serious consequences of human error as the cause of the marriage in the manufacture of food products on automated lines. The nature of the error automated systems operators as a result of the deterioration of psychophysical state of the working person. The importance of modeling the signal generating emergency alarm, can significantly reduce the probability of release of potentially dangerous products. The optimality of the psychophysical state of the control system operator line of food production is highlighted as one of the main criteria for the rational organization of work. The problem of assessing changes in the human condition is also studied, participating in professional activities. The classification of types of functional states control over employee -depending on its purpose. Special attention in work is paid to an example of change of a psychophysical state, expressed in exhaustion of the worker of production. It gives a detailed description of the external signs of exhaustion in the comparative analysis of manual and mental work. The article shows the main tariff and qualification characteristics of activities of operators of lines in production of food products depending on their categories are specified. Describes a group of workers, depending on the operator's activity, indicating the brief description of each group. Based on the analysis of tariff and qualifying characteristics of lines of the operators in the production of food products of different categories, it shows that the range of qualifying categories covers almost al l groups of workers with the exception of the head of the operator. Highlight the desired differentiated approach to the assessment of psychophysiological state operators.

  15. HILBERT-DIRAC OPERATORS IN CLIFFORD ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    F.BRACKX; H.DE SCHEPPER

    2005-01-01

    Around the central theme of "square root" of the Laplace operator it is shown that the classical Riesz potentials of the first and of the second kind allow for an explicit expression of so-called Hilbert-Dirac convolution operators involving natural and complex powers of the Dirac operator.

  16. Analysis of facial characteristics in spectropolarimetric imagery

    Science.gov (United States)

    Zhao, Yongqiang; Zhang, Lei; Yang, Tieheng; Wei, Peifen; Yang, Hongfang

    2007-11-01

    Spectropolarimetric imaging can provide useful discriminating information for human face recognition that cannot be obtained by other imaging methods. This paper examines the ability of face recognition by using spectropolarimetric images. The Spectropolarimetric images were collected by using a CCD camera equipped with a liquid crystal tunable filter, which could capture 32 bands of images over the visible and near-infrared light (0.4μm-0.72μm). Since polarization techniques have better contrast mechanisms for tissue imaging and spectroscopy, and can also provide additional information about the structure of tissues, it is expected that better discriminate performance can be obtained by using polarimetric and spectral information than just using spectral information. An algorithm for facial characteristics analysis is presented to exploit only the spectropolarimetric information from different types of facial tissues. Experiments demonstrate that the proposed algorithm can distinguish efficiently the different facial tissues.

  17. Experimental research on dynamic operating characteristics of a novel silica gel-water adsorption chiller

    Institute of Scientific and Technical Information of China (English)

    WANG Dechang; WU Jingyi; WANG Ruzhu; DOU Weidong

    2007-01-01

    A novel silica gel-water adsorption chiller consisting of two adsorption/desorption chambers and an evaporator with one heat-pipe working chamber is experimentally studied.The dynamic operating characteristics of the chiller and the thermodynamic characteristics of the adsorber are obtained.The experimental results show that the dynamic operating characteristics of the chiller and the thermodynamic characteristics of the adsorber are satisfactory and that the cycle is a novel and effective adsorption cycle.A mass recovery process increases the cyclic adsorption capacity of the system and improves adaptability of the chiller to a lowgrade heat source.In addition,the experiment indicates that this novel chiller is highly suitable for an air conditioning system with a low dehumidification requirement or a system with a large cycle flowrate and an industrial cooling water system.

  18. Recollection is a continuous process: Evidence from plurality memory receiver operating characteristics.

    Science.gov (United States)

    Slotnick, Scott D; Jeye, Brittany M; Dodson, Chad S

    2016-01-01

    Is recollection a continuous/graded process or a threshold/all-or-none process? Receiver operating characteristic (ROC) analysis can answer this question as the continuous model and the threshold model predict curved and linear recollection ROCs, respectively. As memory for plurality, an item's previous singular or plural form, is assumed to rely on recollection, the nature of recollection can be investigated by evaluating plurality memory ROCs. The present study consisted of four experiments. During encoding, words (singular or plural) or objects (single/singular or duplicate/plural) were presented. During retrieval, old items with the same plurality or different plurality were presented. For each item, participants made a confidence rating ranging from "very sure old", which was correct for same plurality items, to "very sure new", which was correct for different plurality items. Each plurality memory ROC was the proportion of same versus different plurality items classified as "old" (i.e., hits versus false alarms). Chi-squared analysis revealed that all of the plurality memory ROCs were adequately fit by the continuous unequal variance model, whereas none of the ROCs were adequately fit by the two-high threshold model. These plurality memory ROC results indicate recollection is a continuous process, which complements previous source memory and associative memory ROC findings.

  19. Data Service:Characteristics,Market Structure,and the Role of Operator

    Institute of Scientific and Technical Information of China (English)

    LI Ruo-peng; LU Ting-jie

    2005-01-01

    To study characteristics and market structure of data service and the role of operator,this paper makes a commercial model by applying the theory of intermediaries and neoclassic economics.Data service has different economic characteristics from voice service.Firstly,production mode of data service is roundabout production,secondly,driving power of data service is economies of specialization,and finally,management method of data service is impersonal management.In data service market,information asymmetry and barrier to entry determine transaction efficiency and the specialization level of service providers indirectly.Therefore,operator should intervene in the market by offering trade service in order to promote development of service providers.Because of different quality of service providers,market structure of data service must be the state that trade platform built by operator and intermediary platform built by operator coexists.

  20. Operational characteristics of dual gain single cavity Nd:YVO4 laser

    Indian Academy of Sciences (India)

    Pranab K Mukhopadhyay; Jogy George; S K Sharma; P K Gupta; T P S Nathan

    2002-01-01

    Operational characteristics of a dual gain single cavity Nd:YVO4 laser have been investigated. With semiconductor diode laser pump power of 2 W, 800 mW output was obtained with a slope efficiency of 49%. Further, by changing the relative orientation of the two crystals the polarization characteristics of the output could be varied. In particular by keeping the two Nd:YVO4 crystals with their -axes orthogonal to each other and adjusting the gain of the crystals so that both operate at approximately the same power level, completely unpolarized beams could be obtained.

  1. Characteristic operator functions for quantum input-plant-output models and coherent control

    Science.gov (United States)

    Gough, John E.

    2015-01-01

    We introduce the characteristic operator as the generalization of the usual concept of a transfer function of linear input-plant-output systems to arbitrary quantum nonlinear Markovian input-output models. This is intended as a tool in the characterization of quantum feedback control systems that fits in with the general theory of networks. The definition exploits the linearity of noise differentials in both the plant Heisenberg equations of motion and the differential form of the input-output relations. Mathematically, the characteristic operator is a matrix of dimension equal to the number of outputs times the number of inputs (which must coincide), but with entries that are operators of the plant system. In this sense, the characteristic operator retains details of the effective plant dynamical structure and is an essentially quantum object. We illustrate the relevance to model reduction and simplification definition by showing that the convergence of the characteristic operator in adiabatic elimination limit models requires the same conditions and assumptions appearing in the work on limit quantum stochastic differential theorems of Bouten and Silberfarb [Commun. Math. Phys. 283, 491-505 (2008)]. This approach also shows in a natural way that the limit coefficients of the quantum stochastic differential equations in adiabatic elimination problems arise algebraically as Schur complements and amounts to a model reduction where the fast degrees of freedom are decoupled from the slow ones and eliminated.

  2. Hydroclimatic Characteristics of the 2012–2015 California Drought from an Operational Perspective

    OpenAIRE

    Minxue He; Mitchel Russo; Michael Anderson

    2017-01-01

    California experienced an extraordinary drought from 2012–2015 (which continues into 2016). This study, from an operational perspective, reviewed the development of this drought in a hydroclimatic framework and examined its characteristics at different temporal and spatial scales. Observed and reconstructed operational hydrologic indices and variables widely used in water resources planning and management at statewide and (hydrologic) regional scales were employed for this purpose. Parsimonio...

  3. Operating characteristics of heavy loaded cylindrical journal bearing with variable axial profile

    Directory of Open Access Journals (Sweden)

    Stanislaw Strzelecki

    2005-12-01

    Full Text Available During the operation of turbounit its bearings displace as a result of heat elongation of bearings supports. It changes the static deflection line of rotor determined during assembly of the turbounit, causing an increase in the stresses on the bearing edges and a decrease in the dynamic state of the machine. One of possibilities to avoid the edge stresses is to apply the bearings with variable axial profile, e.g. hyperboloidal, convex profile in the axial cross-section of bearing. Application of journal bearings with hyperboloidal profile allows to extend the bearing operation range without the stress concentration on the edges of bush. These bearings successfully carry the extreme load in conditions of misaligned axis of journal and the bush eliminating the necessity of using self-aligning bearings. Operating characteristics of bearing include the resulting force, attitude angle, oil film pressure and temperature distributions, minimum oil film thickness, maximum oil film temperature. In literature there is a lack of data on the operating characteristics of heavy loaded hyperboloidal journal bearings operating at the conditions of adiabatic oil film and static equilibrium position of the journal. For the hyperboloidal bearing the operating characteristics have been obtained. Different values of length to diameter ratio, assumed shape and inclination ratio coefficients have been assumed. Iterative solution of the Reynolds', energy and viscosity equations was applied. Adiabatic oil film, laminar flow in the bearing gap as well as aligned and misaligned orientation of journal in the bush were considered.

  4. Analysis of the human operator subsystems

    Science.gov (United States)

    Jones, Lynette A.; Hunter, Ian W.

    1991-01-01

    Except in low-bandwidth systems, knowledge of the human operator transfer function is essential for high-performance telerobotic systems. This information has usually been derived from detailed analyses of tracking performance, in which the human operator is considered as a complete system rather than as a summation of a number of subsystems, each of which influences the operator's output. Studies of one of these subsystems, the limb mechanics system, demonstrate that large parameter variations can occur that can have a profound effect on the stability of force-reflecting telerobot systems. An objective of this research was to decompose the performance of the human operator system in order to establish how the dynamics of each of the elements influence the operator's responses.

  5. Transitioning Results From Recent ONR WESTPAC Field Programs to Operational Use (IWISE Analysis Expansion)

    Science.gov (United States)

    2014-09-30

    Programs to Operational Use (IWISE Analysis Expansion ) Steven R. Ramp Soliton Ocean Services, Inc. 691 Country Club Drive Monterey, CA 93924 phone...characteristics in the deep basin and on the Chinese continental slope and shelf. APPROACH The approach is to particpate in a major ONR-sponsored...SUBTITLE Transitioning Results From Recent ONR WESTPAC Field Programs to Operational Use (IWISE Analysis Expansion ) 5a. CONTRACT NUMBER 5b. GRANT NUMBER

  6. Analysis of Mining Terrain Deformation Characteristics with Deformation Information System

    Science.gov (United States)

    Blachowski, Jan; Milczarek, Wojciech; Grzempowski, Piotr

    2014-05-01

    Mapping and prediction of mining related deformations of the earth surface is an important measure for minimising threat to surface infrastructure, human population, the environment and safety of the mining operation itself arising from underground extraction of useful minerals. The number of methods and techniques used for monitoring and analysis of mining terrain deformations is wide and increasing with the development of geographical information technologies. These include for example: terrestrial geodetic measurements, global positioning systems, remote sensing, spatial interpolation, finite element method modelling, GIS based modelling, geological modelling, empirical modelling using the Knothe theory, artificial neural networks, fuzzy logic calculations and other. The aim of this paper is to introduce the concept of an integrated Deformation Information System (DIS) developed in geographic information systems environment for analysis and modelling of various spatial data related to mining activity and demonstrate its applications for mapping and visualising, as well as identifying possible mining terrain deformation areas with various spatial modelling methods. The DIS concept is based on connected modules that include: the spatial database - the core of the system, the spatial data collection module formed by: terrestrial, satellite and remote sensing measurements of the ground changes, the spatial data mining module for data discovery and extraction, the geological modelling module, the spatial data modeling module with data processing algorithms for spatio-temporal analysis and mapping of mining deformations and their characteristics (e.g. deformation parameters: tilt, curvature and horizontal strain), the multivariate spatial data classification module and the visualization module allowing two-dimensional interactive and static mapping and three-dimensional visualizations of mining ground characteristics. The Systems's functionality has been presented on

  7. Comparative analysis of safety related site characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Johan (ed.)

    2010-12-15

    This document presents a comparative analysis of site characteristics related to long-term safety for the two candidate sites for a final repository for spent nuclear fuel in Forsmark (municipality of Oesthammar) and in Laxemar (municipality of Oskarshamn) from the point of view of site selection. The analyses are based on the updated site descriptions of Forsmark /SKB 2008a/ and Laxemar /SKB 2009a/, together with associated updated repository layouts and designs /SKB 2008b and SKB 2009b/. The basis for the comparison is thus two equally and thoroughly assessed sites. However, the analyses presented here are focussed on differences between the sites rather than evaluating them in absolute terms. The document serves as a basis for the site selection, from the perspective of long-term safety, in SKB's application for a final repository. A full evaluation of safety is made for a repository at the selected site in the safety assessment SR-Site /SKB 2011/, referred to as SR-Site main report in the following

  8. Analysis of Operational Risks in Shipbuilding Industry

    National Research Council Canada - National Science Library

    Daniela MATEI; Mioara CHIRITA

    2012-01-01

    Our paper emphasizes the opportunities provided both for the academic research and companies by using a proposed model of analyzing the operational risks within business in general and shipbuilding...

  9. The Operational Risk – Comparative Analysis

    Directory of Open Access Journals (Sweden)

    Gabriela Victoria Anghelache

    2009-11-01

    Full Text Available In many cases operational risks tend to be underestimated, considering that the losses they cause are generally minor can’t threatening the survival of a bank. Losses resulting from these events come from a complex interaction between organizational factors, personal and market that do not fit into a simple classification scheme. Observing what happened in the past we can say that operational risk is an important question of the financial losses in the banking sector.

  10. Differential Characteristics and Methods of Operation Underlying CAI/CMI Drill and Practice Systems.

    Science.gov (United States)

    Hativa, Nira

    1988-01-01

    Describes computer systems that combine drill and practice instruction with computer-managed instruction (CMI) and identifies system characteristics in four categories: (1) hardware, (2) software, (3) management systems, and (4) methods of daily operation. Topics discussed include microcomputer networks, graphics, feedback, degree of learner…

  11. Employing the therapeutic operating characteristic (TOC) graph for individualised dose prescription

    NARCIS (Netherlands)

    Hoffmann, A.L.; Huizenga, H.; Kaanders, J.H.A.M.

    2013-01-01

    BACKGROUND: In current practice, patients scheduled for radiotherapy are treated according to 'rigid' protocols with predefined dose prescriptions that do not consider risk-taking preferences of individuals. The therapeutic operating characteristic (TOC) graph is applied as a decision-aid to assess

  12. Receiver operating characteristics of perceptrons : Influence of sample size and prevalence

    NARCIS (Netherlands)

    Freking, Ansgar; Biehl, Michael; Braun, Christian; Kinzel, Wolfgang; Meesmann, Malte

    1999-01-01

    In many practical classification problems it is important to distinguish false positive from false negative results when evaluating the performance of the classifier. This is of particular importance for medical diagnostic tests. In this context, receiver operating characteristic (ROC) curves have b

  13. Analysis of the Dynamic Characteristics of Elliptical Gears

    Science.gov (United States)

    Liu, Xing; Nagamura, Kazuteru; Ikejo, Kiyotaka

    To date, elliptical gear has been commonly used in automobile, automatic machinery, pumps, flow meters and printing presses for its particular non-uniform rotation. However, the dynamic characteristics of elliptical gears have not been clarified yet. In this study, The calculation as well as the experiment of two elliptical gears, which are a single elliptical gear and a double elliptical gear, is carried out to analyze the dynamic characteristics of elliptical gears. General factors including the torque, the rotation speed and the tooth root stress of the test gears are investigated. According to the analysis conducted in this study, the dynamic input torque variation of elliptical gear becomes larger along with the increase of operating gear rotation speed and the experimental one increases much faster than the calculated one over the Critical Rotation Speed of Tooth Separation (CRSTS) of elliptical gear. The experimental input rotation speed varies according to the variation of input torque, leading to the difference between the experimental output rotation speed and the desired one. The calculation results of the CRSTS of elliptical gears are almost equal to the experimental ones. The dynamic load variation ratios of elliptical gear at different angular position as well as their changing trends with operating gear rotation speed are quite different from each other. And the experimental dynamic load variation ratios of elliptical gear show difference from the calculated ones because of tooth separation and tooth impact. The agreement of the calculation and experimental results proves the validity of this study.

  14. Hydroclimatic Characteristics of the 2012–2015 California Drought from an Operational Perspective

    Directory of Open Access Journals (Sweden)

    Minxue He

    2017-01-01

    Full Text Available California experienced an extraordinary drought from 2012–2015 (which continues into 2016. This study, from an operational perspective, reviewed the development of this drought in a hydroclimatic framework and examined its characteristics at different temporal and spatial scales. Observed and reconstructed operational hydrologic indices and variables widely used in water resources planning and management at statewide and (hydrologic regional scales were employed for this purpose. Parsimonious metrics typically applied in drought assessment and management practices including the drought monitor category, percent of average, and rank were utilized to facilitate the analysis. The results indicated that the drought was characterized by record low snowpack (statewide four-year accumulated deficit: 280%-of-average, exceptionally low April-July runoff (220%-of-average deficit, and significantly below average reservoir storage (93%-of-average deficit. During the period from 2012–2015, in general, water year 2015 stood out as the driest single year; 2014–2015 was the driest two-year period; and 2013–2015 tended to be the driest three-year period. Contrary to prior studies stating that the 2012–2015 drought was unprecedented, this study illustrated that based on eight out of 28 variables, the 2012–2015 drought was not without precedent in the record period. Spatially, on average, the South Coast Region, the Central Coast Region, the Tulare Region, and the San Joaquin Region generally had the most severe drought conditions. Overall, these findings are highly meaningful for water managers in terms of making better informed adaptive management plans.

  15. Numerical Analysis of Combined Valve Hydrodynamic Characteristics for Turbine System

    Energy Technology Data Exchange (ETDEWEB)

    Bhowmik, P. K.; Shamim, J. A.; Gairola, A.; Arif, M.; Suh, Kune Y. [Seoul National Univ., Seoul (Korea, Republic of)

    2014-05-15

    Flow characteristic curves are plotted by calculating the ratio of the measured mass flow rate versus the theoretical mass flow rate. The flow characteristic curves are utilized to accurately test the performance of the control valve of turbine system to ensure the highest controllability and reliability of the power conversion system of large and small power plants. Turbine converts the kinetic energy of steam to mechanical energy of rotor blades in power conversion system. The electrical energy output from the generator of which the rotor is coupled with that of the turbine depends on the rotation velocity of the turbine bucket. The rotation velocity is proportional to the mass flow rate (steam or gas) to the turbine through valves and nozzles. The turbine comprises fast acting governing control valves and stop valves acting against the seat in the flow passage in the closed position. The turbine control valve regulates the mass flow rate entering the first nozzle of a turbine. The main function of stop valve is to close the fluid inlet rapidly in response to a fast close signal to swiftly cut off the flow through the valve inlet. Both these valves contribute attractively to improvement of the power system transient stability as well. To improve the efficiency of power conversion system many investigation have been done by researcher by focusing on the cycle layout or working fluid or by improving the flow path of the working fluid. The main focus is to find out the best option for combined cycle power plant by analyzing four different cycle configuration. Next research phase focused on different way to enhance the cycle efficiency. As the electrical power output from the generator is proportional to the mass flow rate to the turbine through the valve, it should preferably operate linearly. In reality, however, the valve has the various flow characteristics pursuant to the stem lift. Thus, the flow characteristic and control performance are needed to be designed

  16. Performance analysis of railway infrastructure and operations

    NARCIS (Netherlands)

    Hansen, I.A.; Wiggenraad, P.B.L.; Wolff, J.W.

    2013-01-01

    Research on performance assessment of railway networks and companies has been stimulated by the European policy of deregulation of transport markets, the opening of national railway networks and markets to new entrants and separation of infrastructure and train operation. Recent international benchm

  17. Graduate Student Project: Employer Operations Management Analysis

    Science.gov (United States)

    Fish, Lynn A.

    2008-01-01

    Part-time graduate students at an Association to Advance Collegiate Schools of Business-accredited college complete a unique project by applying operations management concepts to their current employer. More than 92% of 368 graduates indicated that this experiential project was a positive learning experience, and results show a positive impact on…

  18. The Subject Analysis of Payment Systems Characteristics

    Directory of Open Access Journals (Sweden)

    Korobeynikova Olga Mikhaylovna

    2015-09-01

    Full Text Available The article deals with the analysis of payment systems aimed at identifying the categorical terminological apparatus, proving their specific features and revealing the impact of payment systems on the state of money turnover. On the basis of the subject analysis, the author formulates the definitions of a payment system (characterized by increasing speed of effecting payments, by the reduction of costs, by high degree of payments convenience for subjects of transactions, by security of payments, by acceptable level of risks and by social efficiency, a national payment system, and a local payment system (characterized by the growth of economic and social efficiency of systems participants, by the process of money turnover optimization on the basis of saving transaction costs and increasing speed of money flows within the local payment systems. According to the economic levels, the payment systems are divided to macrosystems (national payment systems, mezosystems (payment systems localized on the operational and territorial basis, microsystems (payments by individual economic subjects. The establishment of qualitative features of payment systems, which is a basis of the author’s terminological interpretation, gave a possibility to reveal the cause-effect relations of payment systems influence on the state of money turnover in the involved subjects, and on the economy as a whole. The result of the present research consists in revealing the payment systems influence on the state of money turnover which is significant: at the state and regional level – in the optimization of budget and inter-budgetary relations, in acceleration of the money turnover, in deceleration of the money supply and inflation rate, in reduced need in money emission; at the level of economic entities – in accelerating the money turnover and accounts receivable, in the reduction of debit and credit loans, in the growth of profit (turnover; at the household level – in

  19. A study on operators' cognitive response characteristics to the computerized working environment

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Hee; Lee, Jang Soo; Suh, Sang Moon; Lee, Hyun Cheol; Jung, Kwang Tae; Lee, Dhong Ha

    1998-12-01

    Although the introduction of computerized working environment to the nuclear facilities, the study on the human factors impacts of computers and automation has not been enough like the other industries. It is necessary to prepare the way to cope with the negative aspects in spite of many positive aspects of computerization in nuclear. This study is an empirical study including the survey of the human factor concerning, especially to the cognitive response of operators' and the experiments on the error proneness. At first, we survey the design and its changes of operator interface and interaction in nuclear power plants, and conclude five human factor issues. We discuss situation awareness issues as one of the major human factor concerning, and the assessment method. Secondly, a questionnaire and interviews survey to the operator's response characteristics are performed for possible criterion measures to the in-depth study on the cognitive characteristics. Finally, several experiments are conducted to test the error proneness. The issues and findings of this study could be utilized to any further study on the cognitive characteristic of operators to the computerized work environment.

  20. OPERATIONAL MODAL ANALYSIS SCHEMES USING CORRELATION TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    Zheng Min; Shen Fan; Chen Huaihai

    2005-01-01

    For some large-scale engineering structures in operating conditions, modal parameters estimation must base itself on response-only data. This problem has received a considerable amount of attention in the past few years. It is well known that the cross-correlation function between the measured responses is a sum of complex exponential functions of the same form as the impulse response function of the original system. So this paper presents a time-domain operating modal identification global scheme and a frequency-domain scheme from output-only by coupling the cross-correlation function with conventional modal parameter estimation. The outlined techniques are applied to an airplane model to estimate modal parameters from response-only data.

  1. Analysis of linear partial differential operators

    CERN Document Server

    Hörmander , Lars

    2005-01-01

    This volume is an expanded version of Chapters III, IV, V and VII of my 1963 book "Linear partial differential operators". In addition there is an entirely new chapter on convolution equations, one on scattering theory, and one on methods from the theory of analytic functions of several complex variables. The latter is somewhat limited in scope though since it seems superfluous to duplicate the monographs by Ehrenpreis and by Palamodov on this subject. The reader is assumed to be familiar with distribution theory as presented in Volume I. Most topics discussed here have in fact been encountered in Volume I in special cases, which should provide the necessary motivation and background for a more systematic and precise exposition. The main technical tool in this volume is the Fourier- Laplace transformation. More powerful methods for the study of operators with variable coefficients will be developed in Volume III. However, constant coefficient theory has given the guidance for all that work. Although the field...

  2. Harmonic Analysis Associated with the Generalized Weinstein Operator

    Directory of Open Access Journals (Sweden)

    Ahmed Abouelaz

    2015-11-01

    Full Text Available In this paper we consider a generalized Weinstein operator ∆d,α,n on Rd−1×]0,∞[, which generalizes the Weinstein operator ∆d,α, we define the generalized Weinstein intertwining operator Rα,n which turn out to be transmutation operator between ∆d,α,n and the Laplacian operator ∆d. We build the dual of the generalized Weinstein intertwining operatortRα,n, another hand we prove the formula related Rα,n andtRα,n . We exploit these transmutation operators to develop a new harmonic analysis corresponding to ∆d,α,n.

  3. Digital Advertising Traffic Operation: Flow Management Analysis

    OpenAIRE

    Mas, Massimiliano Dal

    2017-01-01

    In a Web Advertising Traffic Operation the Trafficking Routing Problem (TRP) consists in scheduling the management of Web Advertising (Adv) campaign between Trafficking campaigns in the most efficient way to oversee and manage relationship with partners and internal teams, managing expectations through integration and post-launch in order to ensure success for every stakeholders involved. For our own interest we did that independent research projects also through specific innovative tasks val...

  4. Characteristics of switched reluctance motor operating in continuous and discontinuous conduction mode

    Directory of Open Access Journals (Sweden)

    Ćalasan Martin P.

    2013-01-01

    Full Text Available This paper presents mechanical characteristics of Switched Reluctance Motor (SRM when it operates in Discontinuous Conduction Mode (DCM or in Continuous Conduction Mode (CCM, i.e. when the current through the phase coils (windings flows discontinuously or continuously. Firstly, in order to maximize the output power of SRM optimization of its control parameters was performed, such that the peak and RMS values of the current do not exceed the predefined values. The optimal control parameters vs. rotation speed, as well as the corresponding characteristics of torque, power and efficiency. It is shown that with CCM the machine torque (power, at high speed, can be increased.

  5. Analysis of the offer of chosen tour operator

    OpenAIRE

    Boušová, Ivana

    2012-01-01

    Bachelor thesis is focused on the analysis of tour operator Victoria offer. In theoretical part there are defined basic terms of tourism industry, such as tour operator, tour agent and holiday package. Next part analyzes the offer of the tour operator, which is based on Victoria's profile and services, which are provided by the tour operator. The third part contains important information about the sale. There are mentioned terms of payment, discount programmes, commission sale and forms of pr...

  6. Vibration analysis of a hydro generator for different operating regimes

    Science.gov (United States)

    Haţiegan, C.; Pădureanu, I.; Jurcu, M.; Nedeloni, M. D.; Hamat, C. O.; Chioncel, C. P.; Trocaru, S.; Vasile, O.; Bădescu, O.; Micliuc, D.; (Filip Nedeloni, L.; Băra, A.; (Barboni Haţiegan, L.

    2017-01-01

    Based on experimental measurements, this paper presents the vibration analysis of a hydro generator that equips a Kaplan hydraulic turbine of a Hydropower plant in Romania. This analysis means vibrations measurement to different operating regimes of the hydro generator respectively before installing it and into operation, namely putting off load mode (unexcited and excited) respectively putting on load mode. By comparing, through the experimental results obtained before and after the operation of hydro aggregates are observed vibrations improvements.

  7. RELATIONS OF DERIVATIVE ALGEBRA AND RING OF DIFFERENTIAL OPERATORS IN CHARACTERISTIC p>0

    Institute of Scientific and Technical Information of China (English)

    张江峰

    2002-01-01

    Let K be a field of characteristic p>0. We prove that the derivative algebra of K[x1,…,xn] is a proer subring of the ring of differential operators of K[x1,…,xn]. A concrete example is given to show that there is a differential operator of order p that does not belong to the derivative algebra. By these results, is follows that the derivative algebra is Morita equivalent to K[xp1,…,xpn], and hence its global homological dimension, Krull dimension, K0 group and some other properties are got.

  8. International analysis of the countries where Brazilian franchise chains operate

    Directory of Open Access Journals (Sweden)

    Pedro Lucas de Resende Melo

    2015-03-01

    Full Text Available This paper aims to demonstrate which external environment factors are involved in the international commitment of Brazilian franchise chains. Our objectives herein are to understand which external country characteristics lead to international franchising operations and to ascertain the influence of such characteristics in the commitment of franchise chains in each country they operate in. The database has 54 Brazilian franchise chains with international operations in 26 countries, which implies in 157 franchises operating abroad. Regarding external environment factors, the independent variables form a group divided into market opportunity and business efficiency – trust and ease to doing business. The result of the three distinct clusters show how the market opportunity and the business efficiency (trust and ease in doing business work as drivers to the international operation of Brazilian franchises. The paper shows that the franchise chains operating in the USA (cluster 3 have an inferior international commitment in comparison with the franchises which operate in developed countries and in small Latin American countries (cluster 2. It is also possible to notice a large number of franchises that operate in underdeveloped countries from Latin America and Africa (cluster 1 with worse business efficiency due to the advantage of learning how to operate in a country that could have some similarities with Brazil

  9. Adjusting for covariate effects on classification accuracy using the covariate-adjusted receiver operating characteristic curve.

    Science.gov (United States)

    Janes, Holly; Pepe, Margaret S

    2009-06-01

    Recent scientific and technological innovations have produced an abundance of potential markers that are being investigated for their use in disease screening and diagnosis. In evaluating these markers, it is often necessary to account for covariates associated with the marker of interest. Covariates may include subject characteristics, expertise of the test operator, test procedures or aspects of specimen handling. In this paper, we propose the covariate-adjusted receiver operating characteristic curve, a measure of covariate-adjusted classification accuracy. Nonparametric and semiparametric estimators are proposed, asymptotic distribution theory is provided and finite sample performance is investigated. For illustration we characterize the age-adjusted discriminatory accuracy of prostate-specific antigen as a biomarker for prostate cancer.

  10. Characteristics of operations at fish-landing sites managed by private owners in Thailand

    OpenAIRE

    Yoshimura, Mika; Okamoto, Junichiro; Yasuma, Hiroki; Kimura, Nobuo

    2016-01-01

    This study presents the results of a survey on the operation characteristics of landing sites managed by private owners in Thailand. The survey was conducted by interviewing private landing site owners, managers of fishery cooperatives, middlemen, and fishers. The results of interviews were summarized with respect to scale of business, fisheries, transaction, types of people associated with landing sites, location, and daily schedule. Landing sites were located along canals in coastal provinc...

  11. Complex Network Characteristics and Invulnerability Simulating Analysis of Supply Chain

    OpenAIRE

    Hui-Huang Chen; Ai-Min Lin

    2012-01-01

    To study the characteristics of the complex supply chain, a invulnerability analysis method based on the complex network theory is proposed. The topological structure and dynamic characteristics of the complex supply chain network were analyzed. The fact was found that the network is with general characteristics of the complex network, and with the characteristics of small-world network and scale-free network. A simulation experiment was made on the invulnerability of the supply chain network...

  12. Driving ATHLETE: Analysis of Operational Efficiency

    Science.gov (United States)

    Townsend, Julie; Mittman, David

    2012-01-01

    The All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) is a modular mobility and manipulation platform being developed to support NASA operations in a variety of missions, including exploration of planetary surfaces. The agile system consists of a symmetrical arrangement of six limbs, each with seven articulated degrees of freedom and a powered wheel. This design enables transport of bulky payloads over a wide range of terrain and is envisioned as a tool to mobilize habitats, power-generation equipment, and other supplies for long-range exploration and outpost construction. In 2010, ATHLETE traversed more than 80 km in field environments over eight weeks of testing, demonstrating that the concept is well suited to long-range travel. However, while ATHLETE is designed to travel at speeds of up to 5 kilometers per hour, the observed average traverse rate during field-testing rarely exceeded 1.5 kilometers per hour. This paper investigates sources of inefficiency in ATHLETE traverse operations and identifies targets for improvement of overall traverse rate.

  13. Job Analysis Schedule--Offset Press Operator (Multilith 1250 W) or Offset Duplicating Machine Operator.

    Science.gov (United States)

    Feyock, Anthony J.

    This paper presents an analysis of the job performed by an offset press operator (alternate title is offset duplicating machine operator) of a Multilith 1250 W. First covered is work performed, as follows: prepares dampening unit for printing run, prepares inking unit for printing, readies printing plate for printing, sets up press for running,…

  14. Digital repeat analysis; setup and operation.

    Science.gov (United States)

    Nol, J; Isouard, G; Mirecki, J

    2006-06-01

    Since the emergence of digital imaging, there have been questions about the necessity of continuing reject analysis programs in imaging departments to evaluate performance and quality. As a marketing strategy, most suppliers of digital technology focus on the supremacy of the technology and its ability to reduce the number of repeats, resulting in less radiation doses given to patients and increased productivity in the department. On the other hand, quality assurance radiographers and radiologists believe that repeats are mainly related to positioning skills, and repeat analysis is the main tool to plan training needs to up-skill radiographers. A comparative study between conventional and digital imaging was undertaken to compare outcomes and evaluate the need for reject analysis. However, digital technology still being at its early development stages, setting a credible reject analysis program became the major task of the study. It took the department, with the help of the suppliers of the computed radiography reader and the picture archiving and communication system, over 2 years of software enhancement to build a reliable digital repeat analysis system. The results were supportive of both philosophies; the number of repeats as a result of exposure factors was reduced dramatically; however, the percentage of repeats as a result of positioning skills was slightly on the increase for the simple reason that some rejects in the conventional system qualifying for both exposure and positioning errors were classified as exposure error. The ability of digitally adjusting dark or light images reclassified some of those images as positioning errors.

  15. Wavelet analysis on adeles and pseudo-differential operators

    CERN Document Server

    Khrennikov, A Yu; Shelkovich, V M

    2011-01-01

    This paper is devoted to wavelet analysis on adele ring $\\bA$ and the theory of pseudo-differential operators. We develop the technique which gives the possibility to generalize finite-dimensional results of wavelet analysis to the case of adeles $\\bA$ by using infinite tensor products of Hilbert spaces. The adele ring is roughly speaking a subring of the direct product of all possible ($p$-adic and Archimedean) completions $\\bQ_p$ of the field of rational numbers $\\bQ$ with some conditions at infinity. Using our technique, we prove that $L^2(\\bA)=\\otimes_{e,p\\in\\{\\infty,2,3,5,...}}L^2({\\bQ}_{p})$ is the infinite tensor product of the spaces $L^2({\\bQ}_{p})$ with a stabilization $e=(e_p)_p$, where $e_p(x)=\\Omega(|x|_p)\\in L^2({\\bQ}_{p})$, and $\\Omega$ is a characteristic function of the unit interval $[0,\\,1]$, $\\bQ_p$ is the field of $p$-adic numbers, $p=2,3,5,...$; $\\bQ_\\infty=\\bR$. This description allows us to construct an infinite family of Haar wavelet bases on $L^2(\\bA)$ which can be obtained by shifts...

  16. Determination of a synchronous generator characteristics via Finite Element Analysis

    Directory of Open Access Journals (Sweden)

    Kolondzovski Zlatko

    2005-01-01

    Full Text Available In the paper a determination of characteristics of a small salient pole synchronous generator (SG is presented. Machine characteristics are determined via Finite Element Analysis (FEA and for that purpose is used the software package FEMM Version 3.3. After performing their calculation and analysis, one can conclude that most of the characteristics presented in this paper can be obtained only by using the Finite Element Method (FEM.

  17. FARE device operational characteristics of remote controlled fuelling machine at Wolsong NPP

    Energy Technology Data Exchange (ETDEWEB)

    Namgung, I. [Korea Power Engineering Co., Taejon (Korea, Republic of); Kim, Y. B.; Lee, S. K. [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

    2002-10-01

    There are 4 CANDU6 type reactors operating at Wolsong site. For fuelling operation of certain fuel channels (with flow less than 21.5 kg/s) a FARE (flow Assist Ram Extension) device is used. During the refuelling operation, two remote controlled F/Ms (Fuelling Machines) are attached to a designated fuel channel and carry out refuelling job. The upstream F/M inserts new fuel bundles into the fuel channel while the downstream F/M discharges spent fuel bundles. In order to assist fuelling operation of channels that has lower coolant flow rate, the FARE device is used instead of F/M C-ram to push the fuel bundle string. The FARE device is essentially a flow restricting element that produces enough drag force to push the fuel bundle string toward downstream F/M. Channels that require the use of FARE device for refuelling are located along the outside perimeter of reactor. This paper presents the FARE device design feature, steady state hydraulic and operational characteristics and behavior of the device when coupled with fuel bundle string during fuelling operation. The study showed that the steady state performance of Fare device meets the design objective that was confirmed by downstream F/M C-ram force to be positive.

  18. Operational resilience: concepts, design and analysis

    CERN Document Server

    Ganin, Alexander A; Gutfraind, Alexander; Steen, Nicolas; Keisler, Jeffrey M; Kott, Alexander; Mangoubi, Rami; Linkov, Igor

    2015-01-01

    Building resilience into today's complex infrastructures is critical to the daily functioning of society and its ability to withstand and recover from natural disasters, epidemics, and cyber-threats. This study proposes quantitative measures that implement the definition of engineering resilience advanced by the National Academy of Sciences. The approach is applicable across physical, information, and social domains. It evaluates the critical functionality, defined as a performance function of time set by the stakeholders. Critical functionality is a source of valuable information, such as the integrated system resilience over a time interval, and its robustness. The paper demonstrates the formulation on two classes of models: 1) multi-level directed acyclic graphs, and 2) interdependent coupled networks. For both models synthetic case studies are used to explore trends. For the first class, the approach is also applied to the Linux operating system. Results indicate that desired resilience and robustness lev...

  19. Analysis of information systems for hydropower operations

    Science.gov (United States)

    Sohn, R. L.; Becker, L.; Estes, J.; Simonett, D.; Yeh, W. W. G.

    1976-01-01

    The operations of hydropower systems were analyzed with emphasis on water resource management, to determine how aerospace derived information system technologies can increase energy output. Better utilization of water resources was sought through improved reservoir inflow forecasting based on use of hydrometeorologic information systems with new or improved sensors, satellite data relay systems, and use of advanced scheduling techniques for water release. Specific mechanisms for increased energy output were determined, principally the use of more timely and accurate short term (0-7 days) inflow information to reduce spillage caused by unanticipated dynamic high inflow events. The hydrometeorologic models used in predicting inflows were examined to determine the sensitivity of inflow prediction accuracy to the many variables employed in the models, and the results used to establish information system requirements. Sensor and data handling system capabilities were reviewed and compared to the requirements, and an improved information system concept outlined.

  20. Analysis of Vehicle-Based Security Operations

    Energy Technology Data Exchange (ETDEWEB)

    Carter, Jason M [ORNL; Paul, Nate R [ORNL

    2015-01-01

    Vehicle-to-vehicle (V2V) communications promises to increase roadway safety by providing each vehicle with 360 degree situational awareness of other vehicles in proximity, and by complementing onboard sensors such as radar or camera in detecting imminent crash scenarios. In the United States, approximately three hundred million automobiles could participate in a fully deployed V2V system if Dedicated Short-Range Communication (DSRC) device use becomes mandatory. The system s reliance on continuous communication, however, provides a potential means for unscrupulous persons to transmit false data in an attempt to cause crashes, create traffic congestion, or simply render the system useless. V2V communications must be highly scalable while retaining robust security and privacy preserving features to meet the intra-vehicle and vehicle-to-infrastructure communication requirements for a growing vehicle population. Oakridge National Research Laboratory is investigating a Vehicle-Based Security System (VBSS) to provide security and privacy for a fully deployed V2V and V2I system. In the VBSS an On-board Unit (OBU) generates short-term certificates and signs Basic Safety Messages (BSM) to preserve privacy and enhance security. This work outlines a potential VBSS structure and its operational concepts; it examines how a vehicle-based system might feasibly provide security and privacy, highlights remaining challenges, and explores potential mitigations to address those challenges. Certificate management alternatives that attempt to meet V2V security and privacy requirements have been examined previously by the research community including privacy-preserving group certificates, shared certificates, and functional encryption. Due to real-world operational constraints, adopting one of these approaches for VBSS V2V communication is difficult. Timely misbehavior detection and revocation are still open problems for any V2V system. We explore the alternative approaches that may be

  1. Operational analysis for the drug detection problem

    Science.gov (United States)

    Hoopengardner, Roger L.; Smith, Michael C.

    1994-10-01

    New techniques and sensors to identify the molecular, chemical, or elemental structures unique to drugs are being developed under several national programs. However, the challenge faced by U.S. drug enforcement and Customs officials goes far beyond the simple technical capability to detect an illegal drug. Entry points into the U.S. include ports, border crossings, and airports where cargo ships, vehicles, and aircraft move huge volumes of freight. Current technology and personnel are able to physically inspect only a small fraction of the entering cargo containers. The complexities of how to best utilize new technology to aid the detection process and yet not adversely affect the processing of vehicles and time-sensitive cargo is the challenge faced by these officials. This paper describes an ARPA sponsored initiative to develop a simple, yet useful, method for examining the operational consequences of utilizing various procedures and technologies in combination to achieve an `acceptable' level of detection probability. Since Customs entry points into the U.S. vary from huge seaports to a one lane highway checkpoint between the U.S. and Canadian or Mexico border, no one system can possibly be right for all points. This approach can examine alternative concepts for using different techniques/systems for different types of entry points. Operational measures reported include the average time to process vehicles and containers, the average and maximum numbers in the system at any time, and the utilization of inspection teams. The method is implemented via a PC-based simulation written in GPSS-PC language. Input to the simulation model is (1) the individual detection probabilities and false positive rates for each detection technology or procedure, (2) the inspection time for each procedure, (3) the system configuration, and (4) the physical distance between inspection stations. The model offers on- line graphics to examine effects as the model runs.

  2. Flow and containment characteristics of an air-curtain fume hood operated at high temperatures.

    Science.gov (United States)

    Chen, Jia-Kun; Huang, Rong Fung; Hsin, Pei-Yi; Hsu, Ching Min; Chen, Chun-Wann

    2012-01-01

    The flow and leakage characteristics of the air-curtain fume hood under high temperature operation (between 100°C and 250°C) were studied. Laser-assisted flow visualization technique was used to reveal the hot plume movements in the cabinet and the critical conditions for the hood-top leakage. The sulfur hexafluoride tracer-gas concentration test method was employed to examine the containment spillages from the sash opening and the hood top. It was found that the primary parameters dominating the behavior of the flow field and hood performance are the sash height and the suction velocity as an air-curtain hood is operated at high temperatures. At large sash height and low suction velocity, the air curtain broke down and accompanied with three-dimensional flow in the cabinet. Since the suction velocity was low and the sash opening was large, the makeup air drawn down from the hood top became insufficient to counter act the rising hot plume. Under this situation, containment leakage from the sash opening and the hood top was observed. At small sash opening and high suction velocity, the air curtain presented robust characteristics and the makeup air flow from the hood top was sufficiently large. Therefore the containment leakages from the sash opening and the hood top were not observed. According to the results of experiments, quantitative operation sash height and suction velocity corresponding to the operation temperatures were suggested.

  3. Numerical Ergonomics Analysis in Operation Environment of CNC Machine

    Science.gov (United States)

    Wong, S. F.; Yang, Z. X.

    2010-05-01

    The performance of operator will be affected by different operation environments [1]. Moreover, poor operation environment may cause health problems of the operator [2]. Physical and psychological considerations are two main factors that will affect the performance of operator under different conditions of operation environment. In this paper, applying scientific and systematic methods find out the pivot elements in the field of physical and psychological factors. There are five main factors including light, temperature, noise, air flow and space that are analyzed. A numerical ergonomics model has been built up regarding the analysis results which can support to advance the design of operation environment. Moreover, the output of numerical ergonomic model can provide the safe, comfortable, more productive conditions for the operator.

  4. Automatic Operational Modal Analysis for Aeroelastic Applications

    OpenAIRE

    Schwochow, Jan; Jelicic, G.

    2015-01-01

    The development of new aircraft requires the evaluation of the aeroelastic stability to avoid the phenomenon of flutter, a self-excited oscillation of the airframe. Since the rational analysis of the flutter stability comprises coupled simulations using numerical structural models and unsteady aerodynamic loads, the accomplishment is complex and the implementations must be checked for their validity by comparison of analytical and experimental results. In the so-called Ground Vibration Test (...

  5. Thermal MEMS gyroscope design and characteristics analysis

    OpenAIRE

    Zarei, Nilgoon

    2013-01-01

    Thermal MEMS gyroscope characteristics have been studied to optimize gyroscope performance. Different parameters such as gas properties, heaters power and switching frequency have been optimized to increase the device sensitivity. A new Thermal MEMS gyroscope model referred to as “Forced Convection MEMS Gyroscope” has been introduced. In this design the output signal has been increased by adding external force to the system. Parameter optimization to increase the device efficiency has also...

  6. Human Error Assessmentin Minefield Cleaning Operation Using Human Event Analysis

    Directory of Open Access Journals (Sweden)

    Mohammad Hajiakbari

    2015-12-01

    Full Text Available Background & objective: Human error is one of the main causes of accidents. Due to the unreliability of the human element and the high-risk nature of demining operations, this study aimed to assess and manage human errors likely to occur in such operations. Methods: This study was performed at a demining site in war zones located in the West of Iran. After acquiring an initial familiarity with the operations, methods, and tools of clearing minefields, job task related to clearing landmines were specified. Next, these tasks were studied using HTA and related possible errors were assessed using ATHEANA. Results: de-mining task was composed of four main operations, including primary detection, technical identification, investigation, and neutralization. There were found four main reasons for accidents occurring in such operations; walking on the mines, leaving mines with no action, error in neutralizing operation and environmental explosion. The possibility of human error in mine clearance operations was calculated as 0.010. Conclusion: The main causes of human error in de-mining operations can be attributed to various factors such as poor weather and operating conditions like outdoor work, inappropriate personal protective equipment, personality characteristics, insufficient accuracy in the work, and insufficient time available. To reduce the probability of human error in de-mining operations, the aforementioned factors should be managed properly.

  7. HAWC: Design, Operation, Reconstruction and Analysis

    CERN Document Server

    Smith, Andrew J

    2015-01-01

    The High-Altitude Water Cherenkov (HAWC) Observatory was completed and began full opera- tion on March 20, 2015. The detector consists of an array of 300 water tanks, each containing 200 ktons of purified water and instrumented with 4 PMTs. Located at an elevation of 4100m a.s.l. near the Sierra Negra volcano in central Mexico, HAWC has a threshold for gamma-ray detection well below 1 TeV and a sensitivity to TeV-scale gamma-ray sources an order of magnitude better than previous air-shower arrays. The detector operates 24 hours/day and observes the overhead sky (2 sr), making it an ideal survey instrument. We describe the configuration of HAWC with an emphasis on how the design was optimized, describe the data acquired, reconstructed and an- alyzed. Finally, we will demonstrate the sensitivity of the detector using the observation of the Crab. This paper serves as a detailed technical description of the foundations of the numerous analyses presented at this meeting by members of the HAWC collaboration.

  8. Operational resilience: concepts, design and analysis

    Science.gov (United States)

    Ganin, Alexander A.; Massaro, Emanuele; Gutfraind, Alexander; Steen, Nicolas; Keisler, Jeffrey M.; Kott, Alexander; Mangoubi, Rami; Linkov, Igor

    2016-01-01

    Building resilience into today’s complex infrastructures is critical to the daily functioning of society and its ability to withstand and recover from natural disasters, epidemics, and cyber-threats. This study proposes quantitative measures that capture and implement the definition of engineering resilience advanced by the National Academy of Sciences. The approach is applicable across physical, information, and social domains. It evaluates the critical functionality, defined as a performance function of time set by the stakeholders. Critical functionality is a source of valuable information, such as the integrated system resilience over a time interval, and its robustness. The paper demonstrates the formulation on two classes of models: 1) multi-level directed acyclic graphs, and 2) interdependent coupled networks. For both models synthetic case studies are used to explore trends. For the first class, the approach is also applied to the Linux operating system. Results indicate that desired resilience and robustness levels are achievable by trading off different design parameters, such as redundancy, node recovery time, and backup supply available. The nonlinear relationship between network parameters and resilience levels confirms the utility of the proposed approach, which is of benefit to analysts and designers of complex systems and networks.

  9. Water Hammer Analysis by Characteristic Method

    OpenAIRE

    A. R. Lohrasbi; R. Attarnejad

    2008-01-01

    Rapid changes in the velocity of fluid in closed conduits generate large pressure, which are transmitted through the system with the speed of sound. When the fluid medium is a liquid the pressure surges and related phenomena are described as water hammer. Water hammer is caused by normal operation of the system, such as valve opening or closure, pump starts and stoppages and by abnormal condition, such as power failure. Problem statement: Water hammer causes the additional pressure in water n...

  10. Empirical analysis of industrial operations in Montenegro

    Directory of Open Access Journals (Sweden)

    Galić Jelena

    2012-12-01

    Full Text Available Since the starting process of transition, industrial production in Montenegro has been faced with serious problems and its share in GDP is constantly decreasing. Global financial crises had in large extent negatively influenced industry. Analysis of financial indicators showed that industry had significant losses, problem of undercapitalisation and liquidity problems. If we look by industry sectors, than situation is more favourable in the production of electricity, gas and water compared to extracting industry and mining. In paper is proposed measures of economic policy in order to improve situation in industry.

  11. Unascertained Factor Method of Dynamic Characteristic Analysis for Antenna Structures

    Institute of Scientific and Technical Information of China (English)

    ZHU Zeng-qing; LIANG Zhen-tao; CHEN Jian-jun

    2008-01-01

    The dynamic characteristic analysis model of antenna structures is built, in which the structural physical parameters and geometrical dimensions are all considered as unascertained variables, And a structure dynamic characteristic analysis method based on the unascertained factor method is given. The computational expression of structural characteristic is developed by the mathematics expression of unascertained factor and the principles of unascertained rational numbers arithmetic. An example is given, in which the possible values and confidence degrees of the unascertained structure characteristics are obtained. The calculated results show that the method is feasible and effective.

  12. Analysis of hydraulic characteristics for stream diversion in small stream

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Sang-Jin; Jun, Kye-Won [Chungbuk National University, Cheongju(Korea)

    2001-10-31

    This study is the analysis of hydraulic characteristics for stream diversion reach by numerical model test. Through it we can provide the basis data in flood, and in grasping stream flow characteristics. Analysis of hydraulic characteristics in Seoknam stream were implemented by using computer model HEC-RAS(one-dimensional model) and RMA2(two-dimensional finite element model). As a result we became to know that RMA2 to simulate left, main channel, right in stream is more effective method in analysing flow in channel bends, steep slope, complex bed form effect stream flow characteristics, than HEC-RAS. (author). 13 refs., 3 tabs., 5 figs.

  13. Infrasound Event Analysis into the IDC Operations

    Science.gov (United States)

    Mialle, Pierrick; Bittner, Paulina; Brachet, Nicolas; Brown, David; Given, Jeffrey; Le Bras, Ronan; Coyne, John

    2010-05-01

    The first atmospheric event built only from infrasound arrivals was reported in the Reviewed Event Bulletin (REB) of the International Data Centre (IDC) of the Comprehensive Nuclear Test Ban Treaty Organization (CTBTO) in 2003. In the last decade, 42 infrasound stations from the International Monitoring System (IMS) have been installed and are transmitting data to the IDC. The growing amount of infrasound data and detections produced by the automatic system challenged the station and network processing at the IDC, which required the Organization to redesign the way infrasound data are processed. Each infrasound array is processed separately for signal detection using a progressive multi-channel correlation method (DFX-PMCC). For each detection, signal features - onset time, amplitude, frequency, duration, azimuth, phase velocity, F-statistics - are measured and used to identify a detection as infrasonic, seismic, or noise (including clutter). Infrasonic signals along with seismic and hydroacoustic signals are subsequently associated with Global Association software (GA) between stations to locate events. During detection and association phases, criteria are applied to eliminate clutter, identify signals of interest, and keep the number of automatic events containing infrasound detections to a manageable level for analyst review. The IDC has developed analysis and visualization tools specifically for infrasound review (e.g. Geotool-PMCC). The IDC has continued to build the Infrasound Reference Event Database (IRED) from observations on the IMS network. This database assists both the routine IDC infrasound analysis and analyst training as it reflects the global detection capability of the network, illustrates the spatial and temporal variability of the observed phenomena, and demonstrates the various origins of infragenic sources. Since 2007, the IDC has introduced new analyst procedures to review and add selected infrasound events to the REB. In early 2010, the IDC

  14. Long-term operating characteristics of Japan’s first in-grid HTS power cable

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Tetsutaro, E-mail: nakano.tetsutaro@tepco.co.jp [Tokyo Electric Power Company, 4-1 Egasaki-cho, Tsurumi-ku, Yokohama 230-8510 (Japan); Maruyama, Osamu; Honjo, Shoichi [Tokyo Electric Power Company, 4-1 Egasaki-cho, Tsurumi-ku, Yokohama 230-8510 (Japan); Watanabe, Michihiko; Masuda, Takato; Hirose, Masayuki [Sumitomo Electric Industries, Ltd., 1-1-3 Shimaya, Konohana-ku, Osaka 554-004 (Japan); Shimoda, Masahiro; Nakamura, Naoko; Yaguchi, Hiroharu; Machida, Akito [Mayekawa Mfg. Co., Ltd., 2000 Tatsuzawa, Moriya-shi, Ibaraki 302-0018 (Japan)

    2015-11-15

    Highlights: • The in-grid operation had continued for more than one year without serious troubles. • The LN{sub 2} temperature and pressure were controlled stably within the preset range. • No degradation of I{sub c} occurred against the designed value after in-grid operation. • The degradation rate of cooling power differed among the refrigerators. - Abstract: Tokyo Electric Power Company, Sumitomo Electric Industries, Ltd and Mayekawa Mfg. Co., Ltd have jointly conducted the first in-grid demonstration test of a high-temperature superconducting (HTS) cable in Japan, from FY2007 to FY2013. The objective of this project is to evaluate the reliability, stability and other characteristics of the system. The cable structure used in this project is the type of three-in-one cable. As a coolant, sub-cooled liquid nitrogen flows through the gap between the corrugated cryostat and the three cable cores. This structure can realize compactness and reduce heat invasion compared with three single-core HTS cables housed in separate cryostats. The cooling system consists of six refrigerators, two circulation pumps and a reservoir tank. Each refrigerator has a cooling power of 1.0 kW at 77 K, 0.8 kW at 67 K. The number of operating refrigerators is controlled so that the coolant temperature at the cable inlet is kept to preset value. The HTS cable was connected to the live electricity grid from October 29, 2012 to December 25, 2013. In-grid operation continued for more than one year without any accidental interruption of operation or other operating issues. During this time, we studied the operating performance of the HTS cable in dependence on the sub-cooled LN{sub 2} temperature.

  15. Prediction of Operating Characteristics of Electrotechnical Devices using Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    PASCA Alexandra

    2014-05-01

    Full Text Available The paper purpose is to emphasize the possibilities and the advantages to use the artificial intelligence techniques for operating mode prediction of electrotechnical devices. The considered application consists of the analysis of behavior of an inductive proximity sensor at variation of design parameters.

  16. Detector evaluation for improved situational awareness: Receiver operator characteristic curve based

    NARCIS (Netherlands)

    Wuijckhuijse, A.L. van; Nieuwenhuizen, M.S.

    2016-01-01

    In military and civilian operations good situational awareness is a prerequisite to make proper decisions. The situational awareness is among others based upon intelligence, threat analysis and detection, altogether element of the so-called DIM (detection, identification, monitoring) system. In case

  17. Prediction of Operating Characteristics of Electrotechnical Devices using Artificial Neural Networks

    OpenAIRE

    PASCA Alexandra; MICU Dan Doru; Czumbil, Levente

    2014-01-01

    The paper purpose is to emphasize the possibilities and the advantages to use the artificial intelligence techniques for operating mode prediction of electrotechnical devices. The considered application consists of the analysis of behavior of an inductive proximity sensor at variation of design parameters.

  18. Detector evaluation for improved situational awareness: Receiver operator characteristic curve based

    NARCIS (Netherlands)

    Wuijckhuijse, A.L. van; Nieuwenhuizen, M.S.

    2016-01-01

    In military and civilian operations good situational awareness is a prerequisite to make proper decisions. The situational awareness is among others based upon intelligence, threat analysis and detection, altogether element of the so-called DIM (detection, identification, monitoring) system. In case

  19. Stage Right operational safety analysis and evaluation of Pantex personnel operations

    Energy Technology Data Exchange (ETDEWEB)

    Rountree, S.L.K.; Whitehurst, H.O.; Tomlin, E.H.; Restrepo, L.F. [Sandia National Labs., Albuquerque, NM (United States); White, J. [Sandia National Labs., Albuquerque, NM (United States)]|[Intera, Albuquerque, NM (United States)

    1995-01-01

    This report documents a study (Stage Right Operational Safety Analysis) that was performed to evaluate the effects of new Stage Right operations on the safety of Pantex personnel who perform the operations and maintain the equipment. The primary concern of the evaluation was for personnel safety during Stage Right operations, but operations equipment damage and degradation also were taken into account. This analysis evaluates safety of the work process in the staging of dismantled nuclear weapon pits within the modified Richmond magazines only. This Stage Right Process and Operational Safety Analysis includes the following processes: moving the pelletized drums from the pallet trailer to the pallet turner, staging of pallets and removal of pallets from the magazine, recovery from an incident in a magazine, setting up, opening, and closing a Zone 4 magazine, inventory of pelletized drums in the magazines, transporting pelletized drums from Zone 12 to Zone 4, and maintenance on the shielded lift truck that involves removal of the cab shielding. The analysis includes the following undesirable consequences: injury to personnel, breach of an AL-R8 container, drop of a loaded pallet, damage to equipment, and equipment unreliability.

  20. ATC Operations Analysis via Automatic Recognition of Clearances Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Recent advances in airport surface surveillance have motivated the creation of new tools for analysis of Air Traffic Control (ATC) operations, such as the Surface...

  1. ATC Operations Analysis via Automatic Recognition of Clearances Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Recent advances in airport surface surveillance have motivated the creation of new tools and data sources for analysis of Air Traffic Control (ATC) operations. The...

  2. Surface Operations Data Analysis and Adaptation Tool Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This effort undertook the creation of a Surface Operations Data Analysis and Adaptation (SODAA) tool to store data relevant to airport surface research and...

  3. Main components and characteristics of landslide early warning systems operational worldwide

    Science.gov (United States)

    Piciullo, Luca; Cepeda, José

    2017-04-01

    During the last decades the number of victims and economic losses due to natural hazards are dramatically increased worldwide. The reason can be mainly ascribed to climate changes and urbanization in areas exposed at high level of risk. Among the many mitigation measures available for reducing the risk to life related to natural hazards, early warning systems certainly constitute a significant cost-effective option available to the authorities in charge of risk management and governance. The aim is to help and protect populations exposed to natural hazards, reducing fatalities when major events occur. Landslide is one of the natural hazards addressed by early warning systems. Landslide early warning systems (LEWSs) are mainly composed by the following four components: set-up, correlation laws, decisional algorithm and warning management. Within this framework, the set-up includes all the preliminary actions and choices necessary for designing a LEWS, such as: the area covered by the system, the types of landslides and the monitoring instruments. The monitoring phase provides a series of important information on different variables, considered as triggering factors for landslides, in order to define correlation laws and thresholds. Then, a decisional algorithm is necessary for defining the: number of warning levels to be employed in the system, decision making procedures, and everything else system managers may need for issuing warnings in different warning zones. Finally the warning management is composed by: monitoring and warning strategy; communication strategy; emergency plan and, everything connected to the social sphere. Among LEWSs operational worldwide, two categories can be defined as a function of the scale of analysis: "local" and "territorial" systems. The scale of analysis influences several actions and aspects connected to the design and employment of the system, such as: the actors involved, the monitoring systems, type of landslide phenomena

  4. Performance characteristics of turbo blower in a refuse collecting system according to operation conditions

    Energy Technology Data Exchange (ETDEWEB)

    Jang, C. M.; Kim, D. W. [Korea Institute of Construction Technology, Goyang (Korea, Republic of); Lee, S. Y. [ANST, Seoul (Korea, Republic of)

    2008-10-15

    A simulator for a refuse collecting system is designed to investigate the performance characteristics of a turbo blower operating at different rotational frequencies. The simulator consists of an air intake, a waste chute, circular duct, waste collector and turbo blower. Experimental measurements and numerical simulation with three-dimensional Navier- Stokes equations have been performed to analyze the performance of the turbo blower. Throughout numerical simulation of the simulator, it is found that the input energy of the blower can be reduced by controlling the rotational frequency of impeller while the efficiency of the blower keeps constant. The required outlet pressure and flow rate of the blower can be also adjusted along the system resistance of the refuse collecting system. Detailed flow characteristics inside the blower are analyzed for different rotational frequencies

  5. Job task characteristics of Australian emergency services volunteers during search and rescue operations.

    Science.gov (United States)

    Silk, Aaron; Lenton, Gavin; Savage, Robbie; Aisbett, Brad

    2017-07-28

    Search and rescue operations are necessary in locating, assisting and recovering individuals lost or in distress. In Australia, land-based search and rescue roles require a range of physically demanding tasks undertaken in dynamic and challenging environments. The aim of the current research was to identify and characterise the physically demanding tasks inherent to search and rescue operation personnel within Australia. These aims were met through a subjective job task analysis approach. In total, 11 criterion tasks were identified by personnel. These tasks were the most physically demanding, frequently occurring and operationally important tasks to these specialist roles. Muscular strength was the dominant fitness component for 7 of the 11 tasks. In addition to the discrete criterion tasks, an operational scenario was established. With the tasks and operational scenario identified, objective task analysis procedures can be undertaken so that practitioners can implement evidence-based strategies, such as physical selection procedures and task-based physical training programs, commensurate with the physical demands of search and rescue job roles. Practitioner Summary: The identification of physically demanding tasks amongst specialist emergency service roles predicates health and safety strategies which can be incorporated into organisations. Knowledge of physical task parameters allows employers to mitigate injury risk through the implementation of strategies modelled on the precise physical demands of the role.

  6. Operation characteristics of AMS-02 loop heat pipe with bypass valve

    CERN Document Server

    Wang, N H; Xin, G M; Song, J W; Cui, Z; Burger, J; Du, W J; Luo, F; Cheng, L

    2011-01-01

    Loop heat pipes (LHPs) were designed for the alpha magnetic spectrometer (AMS-02) to dissipate heat from the cryocoolers. A bypass valve is applied to the LHP to keep the cryocooler temperature above its limit (-20A degrees C) in cold environment. Extensive experiments were performed on operation characteristics of LHPs with the bypass valve for AMS-02 during thermal vacuum and thermal balance (TVTB) test. We found that the bypass valve can start up successfully in cold environment. With the bypass valve, the evaporator temperature is stable and can meet the requirement of the cryocooler. We analyzed three operating modes of the bypass valve. Set point temperature and regulation temperature shifts were observed and their relations with the bypass valve temperature were given.

  7. Thermal Aging Characteristics of Insulation Paper in Mineral Oil under Overloaded Operating Transformers

    Science.gov (United States)

    Miyagi, Katsunori; Oe, Etsuo; Yamagata, Naoki; Miyahara, Hideyuki

    A sudden capacity increase in demand during the summer peak, or in contingencies such as malfunctioning transformers, may cause overload for normal transformers. In this paper, on the basis of examples of overloaded transformer operation in distributing substations, thermal aging testing in oil was carried out under various overload patterns, such as short time overload and long time overload, but with the winding insulation paper's life loss kept constant. From the results, various characteristics such as mean degree of polymerization and productions of furfural and (CO2+CO), and their effects on the life loss of the insulation paper were obtained.

  8. Preparation and operation characteristics of organic semiconductor transistor using thin film Al gate and copper phthalocyanine

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The organic static induction transistors (OSITs) are fabricated by the method of evaporating and plating in a vacuum with copper phthalocyanine (CuPc) dye, and has a five layered structure of Au/CuPc/AL/CuPc/Au. The experiment reveals that OSITs have obtained a low driving voltage, high current density and high switch speed such as IDs = 1.2 × 10-6A/mm2 , and the degree of 1 000 Hz. The OSITs have excellent operation characteristics of typical static induction transistors.

  9. Determining Capital Cost in Wastewater Treatment Installations Operating Under Inflow Characteristics Uncertainty

    Science.gov (United States)

    Batzias, D. F.; Pollalis, Y. A.

    2007-12-01

    This work deals with the determination of capital cost in wastewater treatment installations operating under inflow characteristics uncertainty. For this purpose, a methodological framework, under the form of an algorithmic procedure, has been designed/developed and successfully implemented in two cases of biological processing under steady state conditions. The results obtained are in satisfactory approximation with industrial data. Moreover, mathematical formulae have been derived for determining capital cost when processing takes place under unsteady state conditions; in this case, numerical approximation is necessary, since the expressions obtained have not analytic solution. Last, the influence of certain technical parameters on minimum capital cost is discussed.

  10. Operational characteristics of tractors driven by children on farms in the United States and Canada.

    Science.gov (United States)

    Marlenga, B; Pickett, W; Berg, R L; Murphy, D

    2004-01-01

    Farm tractors are an important source of traumatic injury for children on farms. There is, however, no documentation about the age and size of tractors that children are operating and little information about the frequency with which rollover protective structures (ROPS) are used. This study described tractors that children on farms in the U.S. and Canada were operating by age, horsepower, and the presence of ROPS, according to the age and gender of the farm children involved. As a sub-analysis of data compiled during a randomized controlled trial, a descriptive analysis was completed on work exposure data collected by telephone interview. Of the 1,113 children involved in the trial, 522 (47%) were reported to perform at least one job that involved the operation of a farm tractor, and 408 (36.7%) were operating tractors of at least 20 horsepower. The majority of these children were male. There was a wide range of ages and sizes of tractors operated. However, the majority of tractors were between 20 and 70 horsepower and manufactured after 1970. Nearly one-half of the tractors were equipped with ROPS, and these tended to be newer and larger tractors. This analysis provides new data about the broad range of tractors driven by farm children in the U.S. and Canada. The findings point to a need to re-examine the reliance on a single voluntary standard to mitigate the hazard of tractor rollovers and the need for an enhanced safety policy requiring all tractors operated by children be equipped with ROPS.

  11. Plasma characteristics of argon glow discharge produced by AC power supply operating at low frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Kongpiboolkid, Watcharapon; Mongkolnavin, Rattachat [Department of Physics, Facuty of Science, Chulalongkorn University, Bangkok (Thailand); Plasma Technology and Nuclear Fusion Research Unit, Chulalongkorn University, Bangkok (Thailand)

    2015-04-24

    Non-thermal properties of Argon glow discharge operating with various operating pressures were measured and presented in this work. The Argon plasma is produced by a parallel conducting electrodes coupling with a high voltage AC power supply. The power supply can generate high AC voltage at various frequencies. The frequencies for the operation are in the range of a few kHz. The system is capable of generating electric field between the two metal electrodes discharge system. The characteristics of plasma produced were measured by optical emission spectroscopy (OES) technique where electron temperature (T{sub e}) and electron number density (n{sub e}) can be determined by line intensity ratio method. The value of electron number density was then determined from the Saha-Eggert equation. Our results show that the electron number density of the discharge obtained is of the order of 10{sup −17} − 10{sup −18} m{sup −3} where the electron temperature is between 1.00−2.00 eV for various operating frequencies used which are in good agreement with similar results published earlier.

  12. Analysis of Wave Characteristics in Extreme Seas

    Science.gov (United States)

    1991-01-01

    hydrodynamic ’memory’ which complicate the usual analysis are automatically accounted for." With respect to the basic concepts of this methology , Chapter 4...12 - CHESTER A. POLING - FN FAIR WIND II. Episodic Waves: a. Steep Long- Recurring as every 7th * Observations by officers crested or 9th large wave...Grouped waves in seaway. Second CV-62, SEA-LAND Waves wave frequently largest in McLEAN, LST-1193 group. * Observations by officers from ocean weather

  13. Analysis of growth characteristics in short-term divergently selected ...

    African Journals Online (AJOL)

    Analysis of growth characteristics in short-term divergently selected Japanese quail. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... This study was carried out to examine the effect of short-term selection for ...

  14. Hedging rule for reservoir operations: 1. A theoretical analysis

    Science.gov (United States)

    You, Jiing-Yun; Cai, Ximing

    2008-01-01

    Hedging rule policies for reservoir operations accept small deficits in current supply to reduce the probability of a severe water shortage later. This paper expands a theoretical analysis and develops a conceptual two-period model for reservoir operation with hedging that includes uncertain future reservoir inflow explicitly. Extended analysis of the model properties and influencing factors is presented with a general utility function, addressing (1) the starting and ending water availability for hedging, (2) the range of hedging that is related to water demand levels, (3) inflow uncertainty, and (4) evaporation loss. Some intuitive knowledge on reservoir operation is proved or reconfirmed analytically; and new knowledge is derived. This theoretical analysis provides an updated basis for further theoretical study, and the theoretical findings can be used to improve numerical modeling for reservoir operation.

  15. Improvement of the environmental and operational characteristics of vehicles through decreasing the motor fuel density.

    Science.gov (United States)

    Magaril, Elena

    2016-04-01

    The environmental and operational characteristics of motor transport, one of the main consumers of motor fuel and source of toxic emissions, soot, and greenhouse gases, are determined to a large extent by the fuel quality which is characterized by many parameters. Fuel density is one of these parameters and it can serve as an indicator of fuel quality. It has been theoretically substantiated that an increased density of motor fuel has a negative impact both on the environmental and operational characteristics of motor transport. The use of fuels with a high density leads to an increase in carbonization within the engine, adversely affecting the vehicle performance and increasing environmental pollution. A program of technological measures targeted at reducing the density of the fuel used was offered. It includes a solution to the problem posed by changes in the refining capacities ratio and the temperature range of gasoline and diesel fuel boiling, by introducing fuel additives and adding butanes to the gasoline. An environmental tax has been developed which allows oil refineries to have a direct impact on the production of fuels with improved environmental performance, taking into account the need to minimize the density of the fuel within a given category of quality.

  16. Investigation on Operational Unsteady Characteristics of CPL:The Effects of Evaporator and Reservoir

    Institute of Scientific and Technical Information of China (English)

    QuWei; HouZengqi; 等

    1999-01-01

    Capillary Pumped Loop(CPL) is a two phase closed system.The two main components of CPL,both evaporator and reservoir are generally believed to play significant roles in its unsteady operation.In this paper,experimental and theoretical investigations are carried out on the influences of unsteady characteristics of both of them,The previous analytical results show that there is a pressure oscillation source in the evaporator and the internal oscillation frequency can be obtained .The reservoir also has an unsteady characteristics,when the reservoir line has a smaller damping value,there will be a self-oscillation of pressure in the reservoir ,and its analytical frequencies are normally one or two quantities bigger than the inherent frequencies of the evaporator.In order to keep CPL operate steadily,on one hand,the structure of evaporator must be increased to make the coninuous generated vapor flow out the wick easily,on the other hand,the return liquid ought to be subcooled enough to the reservoir temperature set value.

  17. Analysis on Static Characteristics of Heat Transformer

    Science.gov (United States)

    Inoue, Naoyuki; Irie, Kiichi; Fukusumi, Yukihiro

    Absorption heat pump has features to produce high temperature energy by low temperature heat source such as hot water waste heat itself, and it is expected to be a cycle transforming waste heat to usable energy. Particularly promising is the heat pump which produces widely usable steam as high temperature energy. This paper deals with theoretical analysis of various absorption cycles supposing reversible cycles, and discusses the COP, temperature boost and maximum performance comparing with the Carnot cycle. Then simulation model of actual heat pump using H20-LiBr as the working fluid has been developed to predict the performance. A route of heat source hot water from a generator to an evaporator is desirable for high performance. Preheating feed water by weak solution is available for increasing the steam generating rate in the case of steam generation by an absorption heat pump.

  18. Pressure Characteristic Analysis of a Hydraulic System

    Science.gov (United States)

    Cho, H. Y.; Yang, H. J.

    2017-02-01

    EPPR(ElectroProportional Pressure Reducing) valve control the MCV(Main Control Valve) built on the mobile heavy machine. The EPPR valve was tested in the experimental setup and the performance of the valve was compared with that of the existing EPPR valve. On thisstudy, electromagnetic properties analysis using AMESim program was performed to optimize the designing of EPPR Valve (Electric Proportional Pressure Reducing Valve) and by applying its results to the hydraulic system analytical model, performance of the valve could be predicted. Also by comparing the results of the actual experiment and the simulation, The results of thisstudy is that the 3 factor(cone angle, tip width, clearance between sleeve and plunger) have much effectiveness than other components in the EPPR valve.

  19. TMI Fuel Characteristics for Disposal Criticality Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Larry L. Taylor

    2003-09-01

    This report documents the reported contents of the Three Mile Island Unit 2 (TMI-2) canisters. proposed packaging, and degradation scenarios expected in the repository. Most fuels within the U.S. Department of Energy spent nuclear fuel inventory deal with highly enriched uranium, that in most cases require some form of neutronic poisoning inside the fuel canister. The TMI-2 fuel represents a departure from these fuel forms due to its lower enrichment (2.96% max.) values and the disrupted nature of the fuel itself. Criticality analysis of these fuel canisters has been performed over the years to reflect conditions expected during transit from the reactor to the Idaho National Engineering and Environmental Laboratory, water pool storage,1 and transport/dry-pack storage at Idaho Nuclear Technology and Engineering Center.2,3 None of these prior analyses reflect the potential disposal conditions for this fuel inside a postclosure repository.

  20. Analysis Operator Learning and Its Application to Image Reconstruction

    CERN Document Server

    Hawe, Simon; Diepold, Klaus

    2012-01-01

    Exploiting a priori known structural information lies at the core of many image reconstruction methods that can be stated as inverse problems. The synthesis model, which assumes that images can be decomposed into a linear combination of very few atoms of some dictionary, is now a well established tool for the design of image reconstruction algorithms. An interesting alternative is the analysis model, where the signal is multiplied by an analysis operator and the outcome is assumed to be the sparse. This approach has only recently gained increasing interest. The quality of reconstruction methods based on an analysis model severely depends on the right choice of the suitable operator. In this work, we present an algorithm for learning an analysis operator from training images. Our method is based on an $\\ell_p$-norm minimization on the set of full rank matrices with normalized columns. We carefully introduce the employed conjugate gradient method on manifolds, and explain the underlying geometry of the constrai...

  1. Influence of hydrophibization of impellers of centrifugal pumps on their operating characteristics

    Science.gov (United States)

    Volkov, A. V.; Parygin, A. G.; Naumov, A. V.; Vikhlyantsev, A. A.; Šoukal, J.; Sedlář, M.; Komárek, M.

    2016-12-01

    This work presents experimental estimation results of changing of basic operation characteristics of a group of centrifugal pumps covering a range of values of dimensionless power-speed coefficient n s from 33 to 330 after hydrophobization of their impellers' surfaces. Hydrophobization of functional surfaces of impellers in all experiments was performed by formation of structures of organic covers by technology of MPEI NRU, which provides increasing of limiting wetting angle of surfaces to 120° and greater. Results of experimental researches of the influence of hydrophobization of impeller surfaces for high-speed pump ( n s = 330) on its characteristics is presented for the first time. Positive effect of applying hydrophobization technology to impeller surfaces in all the considered range of power-speed coefficient was generalized and estimated. It was shown that hydrophobization of impeller surfaces of centrifugal pumps provides increment to their efficiency factors within an acceptable operation range from 0.5 to 7.5%. Empiric function defining dependencies of efficiency factor increment of pump on relative supply and power-speed coefficient are suggested. Possibilities and estimation of extending acceptable operation range of a pump depending on powerspeed coefficient as a result of impeller surface hydrophobization are shown. Experimental data of comparative cavitation tests of high-speed pumps before and after hydrophobization of their impeller surfaces are generalized for the first time for considered range of power-speed coefficient values. The influence of power-speed coefficient on changing of critical net pump suction head (critical positive suction pressure) is shown. Based on existing knowledge on pumps, an attempt to validate experimentally obtained lows of changing of power and anticavitation features of centrifugal pumps after hydrophobization of their impeller surfaces is made.

  2. Effect of Inductive Coil Geometry on the Operating Characteristics of an Inductive Pulsed Plasma Thruster

    Science.gov (United States)

    Hallock, Ashley K.; Polzin, Kurt A.; Kimberlin, Adam C.; Perdue, Kevin A.

    2012-01-01

    Operational characteristics of two separate inductive thrusters with conical theta pinch coils of different cone angles are explored through thrust stand measurements and time- integrated, unfiltered photography. Trends in impulse bit measurements indicate that, in the present experimental configuration, the thruster with the inductive coil possessing a smaller cone angle produced larger values of thrust, in apparent contradiction to results of a previous thruster acceleration model. Areas of greater light intensity in photographs of thruster operation are assumed to qualitatively represent locations of increased current density. Light intensity is generally greater in images of the thruster with the smaller cone angle when compared to those of the thruster with the larger half cone angle for the same operating conditions. The intensity generally decreases in both thrusters for decreasing mass flow rate and capacitor voltage. The location of brightest light intensity shifts upstream for decreasing mass flow rate of propellant and downstream for decreasing applied voltage. Recognizing that there typically exists an optimum ratio of applied electric field to gas pressure with respect to breakdown efficiency, this result may indicate that the optimum ratio was not achieved uniformly over the coil face, leading to non-uniform and incomplete current sheet formation in violation of the model assumption of immediate formation where all the injected propellant is contained in a magnetically-impermeable current sheet.

  3. Effect of Inductive Coil Geometry on the Operating Characteristics of a Pulsed Inductive Plasma Accelerator

    Science.gov (United States)

    Hallock, Ashley K.; Polzin, Kurt A.; Kimberlin, Adam C.

    2012-01-01

    Operational characteristics of two separate inductive thrusters with coils of different cone angles are explored through thrust stand measurements and time-integrated, un- filtered photography. Trends in impulse bit measurements indicate that, in the present experimental configuration, the thruster with the inductive coil possessing a smaller cone angle produced larger values of thrust, in apparent contradiction to results of a previous thruster acceleration model. Areas of greater light intensity in photographs of thruster operation are assumed to qualitatively represent locations of increased current density. Light intensity is generally greater in images of the thruster with the smaller cone angle when compared to those of the thruster with the larger half cone angle for the same operating conditions. The intensity generally decreases in both thrusters for decreasing mass ow rate and capacitor voltage. The location of brightest light intensity shifts upstream for decreasing mass ow rate of propellant and downstream for decreasing applied voltage. Recognizing that there typically exists an optimum ratio of applied electric field to gas pressure with respect to breakdown efficiency, this result may indicate that the optimum ratio was not achieved uniformly over the coil face, leading to non-uniform and incomplete current sheet formation in violation of the model assumption of immediate formation where all the injected propellant is contained in a magnetically-impermeable current sheet.

  4. Characteristics and Neurological Manifestations of Patients with Operated Lumbar Disc Herniation

    Directory of Open Access Journals (Sweden)

    Amir Mohammad Bazzazi

    2014-01-01

    Full Text Available Background and aim: Lumbar disk herniation is one of the most common causes of surgery in the spine with a variety of signs and symptoms. Sensory and motor deficits, as well as reflex and autonomic abnormalities may be seen. This study aimed to investigate characteristics and neurological manifestations in a series of operated cases with lumbar disc herniation. Methods: In a retrospective setting, profiles of 163 operated cases with lumbar disc herniation were reviewed. Demographics as well as preoperational sign and symptoms were extracted and evaluated. Results: There were 86 females and 77 males with a mean age of 44.85±0.91 (range: 23-78 years in the studied population. The most common involved levels were L4-L5 and L5-S1, respectively. Low back pain, radicular pain, and positive Lasegue test were documented in 98.2%, 96.9% and 77.3% of the patients, respectively. Sensory, motor and reflexive abnormalities were documented in 66.3%, 51.5% and 19.6% of the cases, respectively. Sphincter and sexual dysfunction was presented in 4.9% and 1.2%, respectively. Conclusion: Clinical and neurological signs of operated patients with lumbar disc herniation in the studied center are not far different from available reports in this regard. Keywords: Lumbar disk herniation; Signs and symptoms; Surgery

  5. Controllability Analysis for Operation Margin of Zone 3 Impedance Relay

    Science.gov (United States)

    Li, Shenghu; Yorino, Naoto; Zoka, Yoshifumi

    Undesirable operation of zone 3 impedance relay (mho relays) is a possible factor for causing cascading failure as seen in several previous large scale blackouts, where power flow redistribution and power swing caused by outage or switching operations satisfy the condition for the relay operation. So far, the condition itself has not fully been investigated, and therefore, there has been little attempt to avoid the relay operation by means of direct power flow control. This paper analyzes the condition for zone 3 relay operation from the viewpoint of its sensitivity to power flow. An operating margin for security is defined for each relay to carry out effective monitoring. It is newly pointed out that undesirable operation can be effectively avoided by reactive power controls as well as real power controls. The method to compute the operation margin is also given through the analysis of the optimal Var location to control the operation margin. Effectiveness of the proposed method is demonstrated using the IEEE test systems.

  6. Operational modal analysis of vehicle system based on SSI under operational conditions

    Science.gov (United States)

    Zhou, Suxia; Xie, Yunye; Xie, Jilong; Li, Fang

    2010-03-01

    The modal parameters of linear vehicle system are analyzed by the theoretical modal parameter analysis method first, and then SSI based on operational conditions is presented to form the estimation formula of modal parameters of linear vehicle system. At last, the modal parameters of linear vehicle system are identified by SSI after its vibration test under operational conditions, and are simultaneously compared to the results obtained by the theoretical modal parameter analysis method. Comparison results show discrepancies of 0.61~8.32 percent on modal frequencies and 3.86~11.61 percent on modal damping ratios, which implies that SSI based on the operational condition is feasible and effective, and has comparatively higher precision to meet the needs of engineering.

  7. MANGO – Modal Analysis for Grid Operation: A Method for Damping Improvement through Operating Point Adjustment

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Zhenyu; Zhou, Ning; Tuffner, Francis K.; Chen, Yousu; Trudnowski, Daniel J.; Diao, Ruisheng; Fuller, Jason C.; Mittelstadt, William A.; Hauer, John F.; Dagle, Jeffery E.

    2010-10-18

    Small signal stability problems are one of the major threats to grid stability and reliability in the U.S. power grid. An undamped mode can cause large-amplitude oscillations and may result in system breakups and large-scale blackouts. There have been several incidents of system-wide oscillations. Of those incidents, the most notable is the August 10, 1996 western system breakup, a result of undamped system-wide oscillations. Significant efforts have been devoted to monitoring system oscillatory behaviors from measurements in the past 20 years. The deployment of phasor measurement units (PMU) provides high-precision, time-synchronized data needed for detecting oscillation modes. Measurement-based modal analysis, also known as ModeMeter, uses real-time phasor measurements to identify system oscillation modes and their damping. Low damping indicates potential system stability issues. Modal analysis has been demonstrated with phasor measurements to have the capability of estimating system modes from both oscillation signals and ambient data. With more and more phasor measurements available and ModeMeter techniques maturing, there is yet a need for methods to bring modal analysis from monitoring to actions. The methods should be able to associate low damping with grid operating conditions, so operators or automated operation schemes can respond when low damping is observed. The work presented in this report aims to develop such a method and establish a Modal Analysis for Grid Operation (MANGO) procedure to aid grid operation decision making to increase inter-area modal damping. The procedure can provide operation suggestions (such as increasing generation or decreasing load) for mitigating inter-area oscillations.

  8. An application of operational modal analysis in modal filtering

    Energy Technology Data Exchange (ETDEWEB)

    Kurowski, Piotr; Mendrok, Krzysztof; Uhl, Tadeusz, E-mail: mendrok@agh.edu.pl [AGH University of Science and Technology in Krakow, Al. Mickiewicza 30, 30-059, Krakow (Poland)

    2011-07-19

    Modal filtration in the field of damage detection has many advantages, including: its autonomous operation (without the interaction of qualified staff), low computational cost and low sensitivity to changes in external conditions. However, the main drawback of this group of damage detection methods is its limited applicability to operational data. In this paper a method of modal filter formulation from the in-operational data is described. The basis for this approach is FRFs synthesis using knowledge of the operational modal model. For that purpose a method of operational mode shape scaling is described. This is based on the measurements of several FRFs of the object. The method is then applied to the construction of modal filters and modal filtration. Additionally, the study presents verification of the method using data obtained from simulation and laboratory experiments. Verification consisted of comparing the results of modal filtering based on classical experimental modal analysis with the results of the approach proposed in the work.

  9. An application of operational modal analysis in modal filtering

    Science.gov (United States)

    Kurowski, Piotr; Mendrok, Krzysztof; Uhl, Tadeusz

    2011-07-01

    Modal filtration in the field of damage detection has many advantages, including: its autonomous operation (without the interaction of qualified staff), low computational cost and low sensitivity to changes in external conditions. However, the main drawback of this group of damage detection methods is its limited applicability to operational data. In this paper a method of modal filter formulation from the in-operational data is described. The basis for this approach is FRFs synthesis using knowledge of the operational modal model. For that purpose a method of operational mode shape scaling is described. This is based on the measurements of several FRFs of the object. The method is then applied to the construction of modal filters and modal filtration. Additionally, the study presents verification of the method using data obtained from simulation and laboratory experiments. Verification consisted of comparing the results of modal filtering based on classical experimental modal analysis with the results of the approach proposed in the work.

  10. Analysis on testing and operational reliability of software

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jing; LIU Hong-wei; CUI Gang; WANG Hui-qiang

    2008-01-01

    Software reliability was estimated based on NHPP software reliability growth models. Testing reliability and operational reliability may be essentially different. On the basis of analyzing similarities and differences of the testing phase and the operational phase, using the concept of operational reliability and the testing reliability, different forms of the comparison between the operational failure ratio and the predicted testing failure ratio were conducted, and the mathematical discussion and analysis were performed in detail. Finally, software optimal release was studied using software failure data. The results show that two kinds of conclusions can be derived by applying this method, one conclusion is to continue testing to meet the required reliability level of users, and the other is that testing stops when the required operational reliability is met, thus the testing cost can be reduced.

  11. Hydraulic analysis of the operation of oil and gas wells

    Energy Technology Data Exchange (ETDEWEB)

    Gabor, T.; Szaharov, V.A.; Szilas, A.P.

    1984-01-01

    The results are cited of a study of the operation of operational oil and gas wells. A hydraulic system of operational wells is identified for the first time, which consists of elements of a stratum, well and surface equipment system. After a brief presentation of the rating methods which describe the operation of the elements, the methods for hydraulic analysis of the complete system are detailed. After theoretical presentation of the methods, the course of computer (EVM) programs, developed for practical purposes, is shown. These programs may be used to solve two basic problems in gusher extraction of oil: identification of the maximal flow rate of a gusher well and the operational point of a well which has a wellhead coupling.

  12. The Analysis of the Romanian Tour Operator Agencies Sector

    OpenAIRE

    Andreea Marin-Pantelescu; Laura-Cristina Maniu

    2014-01-01

    Tour operators perform an important and specific function in the tourism activity. They purchase distinct elements of transport, accommodation, meals, entertainment and other services, and combine them into a tour package which they can sell directly or indirectly to tourists. The present paper presents an analysis of the Romanian tour operator agencies sector and the evolution inside this important domain of activity using important key figures as: the number of Romanian tourists taking part...

  13. Analysis of Optimal Operation of an Energy Integrated Distillation Plant

    DEFF Research Database (Denmark)

    Li, Hong Wen; Hansen, C.A.; Gani, Rafiqul

    2003-01-01

    distillation plant is investigated more closely with the purpose of elucidating essential decisions behind planning experiments, which are suitable for identifying models and constraints. The basis for analysis of optimal operation is the type of operation upon which an application focuses. In this paper...... and their influence upon the further decisions behind the experimental design. An energy-integrated distillation column, which may exhibit fold bifurcations, is used as a relevant example process....

  14. Operational logs analysis at ALMA observatory based on ELK stack

    Science.gov (United States)

    Gil, Juan P.; Reveco, Johnny; Shen, Tzu-Chiang

    2016-07-01

    During operations, the ALMA observatory generates a huge amount of logs which contain not only valuable information related to specific failures but also for long term performance analysis. We implemented a big data solution based on Elasticsearch, Logstash and Kibana. They are configured as decoupled system which causes zero impact on the existent operations. It is able to keep more than six months of operation logs online. In this paper, we'll describe this infrastructure, applications built on top of it, and the problems that we faced during its implementation.

  15. [Characteristics of microbial community and operation efficiency in biofilter process for drinking water purification].

    Science.gov (United States)

    Xiang, Hong; Lü, Xi-Wu; Yang, Fei; Yin, Li-Hong; Zhu, Guang-Can

    2011-04-01

    In order to explore characteristics of microbial community and operation efficiency in biofilter (biologically-enhanced active filter and biological activated carbon filter) process for drinking water purification, Biolog and polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) techniques were applied to analyze the metabolic function and structure of microbial community developing in biofilters. Water quality parameters, such as NH; -N, NO; -N, permanganate index, UV254 and BDOC etc, were determined in inflow and outflow of biofilters for investigation of operation efficiency of the biofilters. The results show that metabolic capacity of microbial community of the raw water is reduced after the biofilters, which reflect that metabolically active microbial communities in the raw water can be intercepted by biofilters. After 6 months operation of biofilters, the metabolic profiles of microbial communities are similar between two kinds of biologically-enhanced active filters, and utilization of carbon sources of microbial communities in the two filters are 73.4% and 75.5%, respectively. The metabolic profiles of microbial communities in two biological activated carbon filters showed significant difference. The carbon source utilization rate of microbial community in granule-activated carbon filter is 79.6%, which is obviously higher than 53.8% of the rate in the columnar activated carbon filter (p water purification efficiency was not significant (p > 0.05). However, in biological activated carbon filters, granule-activated carbon is conducive to microbial growth and reproduction, and the microbial communities in the biofilter present high metabolic activities, and the removal efficiency for NH4(+)-N, permanganate index and BDOC is better than the columnar activated carbon filter(p < 0.05). The results also suggest that operation efficiency of biofilter is related to the metabolic capacity of microbial community in biofilter.

  16. Structural analysis and functional characteristics of greenhouses in ...

    African Journals Online (AJOL)

    USER

    2010-05-24

    May 24, 2010 ... This study was carried out to determine the structural analysis and functional characteristics of the greenhouses ..... Duncan test results for mean separation of calculated stretch ratios, ... and Organic Fertilizers and Possible Effects in the Greenhouses of ... Structural analysis of greenhouses: A case study in.

  17. Performance and Degradation Analysis of Operating PV Systems

    Science.gov (United States)

    Da Silva Freire, Felipe

    The environmental concerns together with the decrease in technology cost lead the solar market to growth rapidly along the last decade. The photovoltaic (PV) systems are one of the solar energy alternatives and the silicon solar cells are currently the most widespread technology. Photovoltaic (PV) modules are considered the most reliable component of a photovoltaic system. The reliability and lifetime depends on the modules energy conversion performance and degradation modes. The analysis of monitoring data give insights about the PV system performance along its service time. The comparison between this data and mathematical models configure a way to predict the futures and new PV installations performance. The goal of this study is to understand the PV systems performance and degradation along its lifetime. A mathematical model was employed to predict the power output of a real, relatively new operating PV system with respect to environmental parameters temperature, irradiance and cloud coverage. The model used is based on one diode ideality factor and takes into account the parasitic series resistance. The results have been compared with the actual PV output data collected for the year 2014 and show good correlation. As the model predicts the system power output assuming the system in new conditions, the deviation in performance of the real data in comparison to the modeling results need to be further investigated for systems in service for longer time. For this propose, the study presents a condensed review of various causes of degradation in silicon PV modules and techniques to observe and investigate these degradation mechanisms. Major effects on output performance exhibit increase in observed ideality factor n2 and recombination current J02 primarily caused by decrease in minority carrier lifetime, shunts and increase in series resistance. The study further, investigates the governing degradation modes on a ten years old PV crystalline silicon module

  18. ANALYSIS OF AVAILABILITY AND RELIABILITY IN RHIC OPERATIONS.

    Energy Technology Data Exchange (ETDEWEB)

    PILAT, F.; INGRASSIA, P.; MICHNOFF, R.

    2006-06-26

    RHIC has been successfully operated for 5 years as a collider for different species, ranging from heavy ions including gold and copper, to polarized protons. We present a critical analysis of reliability data for RHIC that not only identifies the principal factors limiting availability but also evaluates critical choices at design times and assess their impact on present machine performance. RHIC availability data are typical when compared to similar high-energy colliders. The critical analysis of operations data is the basis for studies and plans to improve RHIC machine availability beyond the 50-60% typical of high-energy colliders.

  19. The comparison and analysis of real estate operation in China

    Institute of Scientific and Technical Information of China (English)

    张跃松

    2004-01-01

    This paper raises the comparison method of operational stages of the real estate market. In order to select similar operational stages, we established an analysis model by applying fuzzy grade-of-membership clustering in this paper. Firstly, we select the materials information of the real estate market in America, Germany and Japan. Secondly, the real estate markets of America, Germany and Japan are divided into several different stages. Lastly, we apply the method of fuzzy grade-of-membership clustering to select comparable stages. The result of analysis indicates that the real estate market of Japan and Germany (1960-1980) are similar to the market in China.

  20. Analysis on the LODHR Event during Refueling Pool Operation

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Dong Hyun; Huh, Jae Young; Lee, Gyu Cheon; Kim, Shin Whan [KEPCO E and C, Inc., Daejeon (Korea, Republic of)

    2015-10-15

    In this paper, the analysis is performed to evaluate the time to core uncovery and core damage as well as the time to core boiling. To analyze thermal hydraulic behaviors during refueling pool operation, RELAP5/MOD3.3 is used adopting the Henry-Fauske (H-F) critical flow model. The input modeling method adopts the method of SFP. The purpose of the analysis is to study the major results and T-H behaviors regarding to safety aspect during LODHR event at the refueling pool operation. In the present low power and shutdown (LPSD) probabilistic safety assessment (PSA) thermal hydraulic (T-H) analysis for dealing with various different plant operational states (POSs), the T-H analysis for the duration of refueling pool operation is omitted as it is considered less severe procedure during overhaul period for optimized power reactor 1000 (OPR1000). Instead only spent fuel pool analysis has been performed representing refueling operation mode (operation mode 6). However, in NUREG-1449, the NRC staff identified twelve technical issues that warrant further evaluation regarding shutdown and low power operation at U.S commercial nuclear power plants. One of issues identified for further evaluation is to evaluate the effect of PWR upper internals, that is, the PWR upper internals may inhibit water in the refueling pool from entering the core during a loss of decay heat removal event (LODHR). Per a commission paper (SECY-91-283) which reported progress to date on the evaluation, the NRC staff requested to address this safety issue by performing a quantitative and qualitative analysis. An analysis of LODHR was performed for advanced power reactor 1400 (APR1400) but it was focused to evaluate the initiation time of core boiling. As the results of the analysis for the LODHR during refueling pool operation, even though the core boiling is occurred in 15 minutes, there is enough water to cover the core and it prevents the core from damaging. The time is taken more than 4 days until the

  1. Approaches for delineating landslide hazard areas using receiver operating characteristic in an advanced calibrating precision soil erosion model

    Directory of Open Access Journals (Sweden)

    P. T. Ghazvinei

    2015-10-01

    Full Text Available Soil erosion is undesirable natural event that causes land degradation and desertification. Identify the erosion-prone areas is a major component of preventive measures. Recent landslide damages at different regions lead us to develop a model of the erosion susceptibility map using empirical method (RUSLE. A landslide-location map was established by interpreting satellite image. Field observation data was used to validate the intensity of soil erosion. Further, a correlation analysis was conducted to investigate the "Receiver Operating Characteristic" and frequency ratio. Results showed a satisfactory correlation between the prepared RUSLE-based soil erosion map and actual landslide distribution. The proposed model can effectively predict the landslide events in soil-erosion area. Such a reliable predictive model is an effective management facility for the regional landslide forecasting system.

  2. Stirling Convertor Extended Operation Testing and Data Analysis at Glenn Research Center

    Science.gov (United States)

    Cornell, Peggy A.; Lewandowski, Edward J.; Oriti, Salvatore M.; Wilson, Scott D.

    2010-01-01

    Extended operation of Stirling convertors is essential to the development of radioisotope power systems and their potential use for longduration missions. To document the reliability of the convertors, regular monitoring and analysis of the extended operation data is particularly valuable, allowing us to better understand and quantify long-life characteristics of the convertors. Furthermore, investigation and comparison of the extended operation data to baseline performance data provides an opportunity to understand system behavior should any off-nominal performance occur. Glenn Research Center (GRC) has tested 16 Stirling convertors under 24-hr unattended extended operation, including four that have operated in a thermal vacuum environment and two that are operating in the Advanced Stirling Radioisotope Generator Engineering Unit. Ten of the sixteen convertors are the Advanced Stirling Convertors (ASC) developed by Sunpower, Inc. with GRC. These are highly efficient (conversion efficiency of up to 38 percent for the ASC-1), low-mass convertors that have evolved through technologically progressive convertor builds. Six convertors at GRC are Technology Demonstration Convertors from Infinia Corporation. They have achieved greater than 27 percent conversion efficiency and have accumulated over 185,000 of the total 265,000 hr of extended operation at GRC. This paper presents the extended operation testing and data analysis of free-piston Stirling convertors at NASA GRC as well as how these tests have contributed to the Stirling convertor s progression toward flight.

  3. Consumer-operated service organizations: organizational characteristics, community relationships, and the potential for citizenship.

    Science.gov (United States)

    Tanenbaum, Sandra J

    2012-08-01

    Consumer-operated service organizations (COSOs) are independent organizations whose administrative and financial control resides with consumers. Based on a 2008 mail survey and followup interviews conducted in 2009, this study depicts the internal characteristics and external relationships, as well as some relationships between the two, of COSOs in one state. Profiles include on the one hand, governance structures, services provided, sources and levels of funding, etc. and on the other, relationships between COSOs and other actors in the mental health system and the local community. COSOs emerge as more self-governing and community-based than required by certification requirements and as developing internally and externally in tandem. COSOs are not only adjunct or alternative service providers, but also civic associations and loci for the expression of citizenship by mentally ill people.

  4. Influence of Landfill Operation and Tropical Seasonal Variation on Leachate Characteristics: Results from Lysimeter Experiment

    Directory of Open Access Journals (Sweden)

    Islam M. Rafizul

    2012-01-01

    Full Text Available This study demonstrates the influence of lysimeter operational condition and tropical seasonal variation of leachate characteristics generated from municipal solid waste (MSW deposited in landfill lysimeter at KUET campus, Bangladesh. Three different situations of landfill were considered here as well as both the open dump lysimeter-A having a base liner and sanitary landfill lysimeter-B and C at two different types of cap liner were simulated. The leachate characteristics, leachate generation and climatic influence parameter had been continually monitored, from June 2008 to May 2010. This period covers both dry and rainy season. The leachate generation followed the rainfall pattern and the open dump lysimeter-A without top cover was recorded to have the highest leachate generation. Moreover, the open dump lysimeter-A had lower concentration and load of total kjeldahl nitrogen (TKN, ammonia nitrogen (NH4-N and dissolved organic carbon (DOC, while chemical oxygen demand (COD and biological oxygen demand (BOD5 concentration were higher compared with sanitary lysimeter-B and C. On the other hand, sanitary lysimeter-B, not only had lowest leachate generation, but also produced reasonably low COD and BOD5 concentration compared with open dump lysimeter-A. Based on evaluated results, it was also concluded that metal concentrations which were comparatively higher in leachate of open dump lysimeter were Ca and K, however, the heavy metal concentrations of Cd, Cu, Zn and Mn, and those apparently lower were metals of Na, Mg and Fe as well as heavy metals of Cr, Pb and Ni. However, significant release of heavy metals under open dump lysimeter was observed compared to sanitary lysimeter. Moreover, meaningful correlation between DOC and leaching of Cu and Pb was observed. Result reveals that lysimeter operational mode had direct effect on leachate quality. Finally, it can be concluded that the knowledge of leachate quality will be useful in planning and

  5. Operational Characteristics and Plasma Measurements in a Low-Energy FARAD Thruster

    Science.gov (United States)

    Polzin, K. A.; Best, S.; Rose, M. F.; Miller, R.; Owens, T.

    2008-01-01

    Pulsed inductive plasma accelerators are spacecraft propulsion devices in which energy is stored in a capacitor and then discharged through an inductive coil. The device is electrodeless, inducing a plasma current sheet in propellant located near the face of the coil. The propellant is accelerated and expelled at a high exhaust velocity (order of 10 km/s) through the interaction of the plasma current with an induced magnetic field. The Faraday Accelerator with RF-Assisted Discharge (FARAD) thruster is a type of pulsed inductive plasma accelerator in which the plasma is preionized by a mechanism separate from that used to form the current sheet and accelerate the gas. Employing a separate preionization mechanism in this manner allows for the formation of an inductive current sheet at much lower discharge energies and voltages than those found in previous pulsed inductive accelerators like the Pulsed Inductive Thruster (PIT). In this paper, we present measurements aimed at quantifying the thruster's overall operational characteristics and providing additional insight into the nature of operation. Measurements of the terminal current and voltage characteristics during the pulse help quantify the output of the pulsed power train driving the acceleration coil. A fast ionization gauge is used to measure the evolution of the neutral gas distribution in the accelerator prior to a pulse. The preionization process is diagnosed by monitoring light emission from the gas using a photodiode, and a time-resolved global view of the evolving, accelerating current sheet is obtained using a fast-framing camera. Local plasma and field measurements are obtained using an array of intrusive probes. The local induced magnetic field and azimuthal current density are measured using B-dot probes and mini-Rogowski coils, respectively. Direct probing of the number density and electron temperature is performed using a triple probe.

  6. Operative and postoperative control of variations in characteristics of physicochemical processes in NPP circuits

    Energy Technology Data Exchange (ETDEWEB)

    Vilkov, N.Ya.; Krjukov, Yu.V.; Blinov, S.V. [Alexandrov Research Inst. of Technology (Russian Federation); Fedoseev, M.V. [VNIIAES (Russian Federation)

    2002-07-01

    Based on actual data obtained from operative chemical monitoring in operating NPPs, the authors show the use of some probability diagnosis methods in practical applications such as identification of anomalies of the water chemistry condition, specifically, in the following: detecting violation of control limits a priori determined for the water chemistry parameters, using the control card method; construction of detectors for identifying probably (statistically) significant stepwise changes in the current arithmetical mean of the water chemistry parametric values; identifying successive changes in the behavior of robust estimators of the monitored parameters values; construction of robust linear regression prognostic models for dynamic changes in the monitored parameters values; correlation analysis of time series formed from the measured data on the water chemistry connected parameters (which are lumped (concentrated at one control point) and/or distributed along the coolant path). (author)

  7. [Characteristics and operation of enhanced continuous bio-hydrogen production reactor using support carrier].

    Science.gov (United States)

    Ren, Nan-qi; Tang, Jing; Gong, Man-li

    2006-06-01

    A kind of granular activated carbon, whose granular size is no more than 2mm and specific gravity is 1.54g/cm3, was used as the support carrier to allow retention of activated sludge within a continuous stirred-tank reactor (CSTR) using molasses wastewater as substrate for bio-hydrogen production. Continuous operation characteristics and operational controlling strategy of the enhanced continuous bio-hydrogen production system were investigated. It was indicated that, support carriers could expand the activity scope of hydrogen production bacteria, make the system fairly stable in response to organic load impact and low pH value (pH reactor at low HRT. The reactor with ethanol-type fermentation achieved an optimal hydrogen production rate of 0.37L/(g x d), while the pH value ranged from 3.8 to 4.4, and the hydrogen content was approximately 40% approximately 57% of biogas. It is effective to inhibit the methanogens by reducing the pH value of the bio-hydrogen production system, consequently accelerate the start-up of the reactor.

  8. Effect of activated sludge properties and membrane operation conditions on fouling characteristics in membrane bioreactors.

    Science.gov (United States)

    Choi, Hyeok; Zhang, Kai; Dionysiou, Dionysios D; Oerther, Daniel B; Sorial, George A

    2006-06-01

    Biofouling control is considered to be a major challenge in operating membrane bioreactors (MBRs) for the treatment of wastewater. This study examined the impact of biological, chemical, and physical properties of activated sludge on membrane filtration performance in laboratory-scale MBRs. Sludges with different microbial communities were produced using pseudo-continuous stirred-tank reactors and pseudo-plug flow reactors treating a synthetic paper mill wastewater. Various filtration resistances were used to investigate membrane fouling characteristics, and molecular biology tools targeting 16S ribosomal DNA gene sequences were used to identify predominant bacterial populations in the sludges or attached to the fouled membranes. Filtration experiments using axenic cultures of Escherichia coli, Acinetobacter calcoaceticus, and Gordonia amarae were also performed to better understand the initiation and development of biofouling. The results showed that the tendency of membranes to biofoul depended upon membrane operating conditions as well as the properties of the activated sludge in the MBR systems. Specific bacterial populations, which were not dominant in the activated sludges, were selectively accumulated on the membrane surface leading to the development of irreversible biofouling.

  9. Operating characteristics of a new ion source for KSTAR neutral beam injection system.

    Science.gov (United States)

    Kim, Tae-Seong; Jeong, Seung Ho; Chang, Doo-Hee; Lee, Kwang Won; In, Sang-Ryul

    2014-02-01

    A new positive ion source for the Korea Superconducting Tokamak Advanced Research neutral beam injection (KSTAR NBI-1) system was designed, fabricated, and assembled in 2011. The characteristics of the arc discharge and beam extraction were investigated using hydrogen and helium gas to find the optimum operating parameters of the arc power, filament voltage, gas pressure, extracting voltage, accelerating voltage, and decelerating voltage at the neutral beam test stand at the Korea Atomic Energy Research Institute in 2012. Based on the optimum operating condition, the new ion source was then conditioned, and performance tests were primarily finished. The accelerator system with enlarged apertures can extract a maximum 65 A ion beam with a beam energy of 100 keV. The arc efficiency and optimum beam perveance, at which the beam divergence is at a minimum, are estimated to be 1.0 A/kW and 2.5 uP, respectively. The beam extraction tests show that the design goal of delivering a 2 MW deuterium neutral beam into the KSTAR Tokamak plasma is achievable.

  10. Constrained Overcomplete Analysis Operator Learning for Cosparse Signal Modelling

    CERN Document Server

    Yaghoobi, Mehrdad; Gribonval, Remi; Davies, Mike E

    2012-01-01

    We consider the problem of learning a low-dimensional signal model from a collection of training samples. The mainstream approach would be to learn an overcomplete dictionary to provide good approximations of the training samples using sparse synthesis coefficients. This famous sparse model has a less well known counterpart, in analysis form, called the cosparse analysis model. In this new model, signals are characterised by their parsimony in a transformed domain using an overcomplete (linear) analysis operator. We propose to learn an analysis operator from a training corpus using a constrained optimisation framework based on L1 optimisation. The reason for introducing a constraint in the optimisation framework is to exclude trivial solutions. Although there is no final answer here for which constraint is the most relevant constraint, we investigate some conventional constraints in the model adaptation field and use the uniformly normalised tight frame (UNTF) for this purpose. We then derive a practical lear...

  11. One-Click Data Analysis Software for Science Operations

    Science.gov (United States)

    Navarro, Vicente

    2015-12-01

    One of the important activities of ESA Science Operations Centre is to provide Data Analysis Software (DAS) to enable users and scientists to process data further to higher levels. During operations and post-operations, Data Analysis Software (DAS) is fully maintained and updated for new OS and library releases. Nonetheless, once a Mission goes into the "legacy" phase, there are very limited funds and long-term preservation becomes more and more difficult. Building on Virtual Machine (VM), Cloud computing and Software as a Service (SaaS) technologies, this project has aimed at providing long-term preservation of Data Analysis Software for the following missions: - PIA for ISO (1995) - SAS for XMM-Newton (1999) - Hipe for Herschel (2009) - EXIA for EXOSAT (1983) Following goals have guided the architecture: - Support for all operations, post-operations and archive/legacy phases. - Support for local (user's computer) and cloud environments (ESAC-Cloud, Amazon - AWS). - Support for expert users, requiring full capabilities. - Provision of a simple web-based interface. This talk describes the architecture, challenges, results and lessons learnt gathered in this project.

  12. Analysis of the dynamic hysteresis characteristic of finger seal

    Institute of Scientific and Technical Information of China (English)

    LEI Yanni; CHEN Guoding

    2007-01-01

    The research about hysteresis characteristic of finger seal (FS), which was carried out based on the model with static loads, could not reflect the dynamics behavior of FS system when the rotor runs at high speed. To solve this problem, the relations between the dynamics parameters, structure parameters as well as working parameters in the system were given out through the analysis of finite element analysis result. A mass-spring-damper dynamics model of FS system was proposed and the hysteresis characteristic of the FS system was analyzed. This work shows that the dynamics characteristic analysis of the FS is necessary and the dynamics model proposed in this paper is valid. This dynamics model is the basis for the optimization design of FS system.

  13. Some operator ideals in non-commutative functional analysis

    CERN Document Server

    Fidaleo, F

    1997-01-01

    We characterize classes of linear maps between operator spaces $E$, $F$ which factorize through maps arising in a natural manner via the Pisier vector-valued non-commutative $L^p$ spaces $S_p[E^*]$ based on the Schatten classes on the separable Hilbert space $l^2$. These classes of maps can be viewed as quasi-normed operator ideals in the category of operator spaces, that is in non-commutative (quantized) functional analysis. The case $p=2$ provides a Banach operator ideal and allows us to characterize the split property for inclusions of $W^*$-algebras by the 2-factorable maps. The various characterizations of the split property have interesting applications in Quantum Field Theory.

  14. FACEBOOK CONTENT ANALYSIS OF BANKS OPERATING ON SLOVAK MARKET

    OpenAIRE

    Róbert Štefko; Radovan Baèík; Igor Fedorko

    2014-01-01

    This article uses content analysis to identify the extent of users’ involvement in the corporate communication on the social network Facebook. This article focuses on the Facebook pages of the largest banking institutions operating in Slovakia - regarding the volume of their total assets in 2012. The analysis shows that the criterion for the success of the post on the largest social network Facebook is an effort to maximize the involvement of users in the corporate communication through the i...

  15. Simulation Modeling and Analysis of Operator-Machine Ratio

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Based on a simulation model of a semiconductor manufacturer, operator-machine ratio (OMR) analysis is made using work study and time study. Through sensitivity analysis, it is found that labor utilization decreases with the increase of lot size.Meanwhile, it is able to identify that the OMR for this company should be improved from 1∶3 to 1∶5. An application result shows that the proposed model can effectively improve the OMR by 33%.

  16. Incident investigation and analysis for E and P operations

    Energy Technology Data Exchange (ETDEWEB)

    Waterfall, K.W.; Willink, C.A.T.; Milne, D.J. (Shell International Petroleum Mij. B.V., The Hague (Netherlands))

    1995-01-01

    Incident investigation and analysis in Shell E and P operations is part of performance monitoring in health, safety, and environment (HSE) management systems. The focus is on identifying underlying causes. A step-wise approach is given from immediate response through determining the level of investigation, coverage of investigation aspects, analysis, recording, and follow-up. The means to analyze incidents by application of the Tripod system, which is directed toward understanding underlying causes of incidents, are reviewed.

  17. Space system operations and support cost analysis using Markov chains

    Science.gov (United States)

    Unal, Resit; Dean, Edwin B.; Moore, Arlene A.; Fairbairn, Robert E.

    1990-01-01

    This paper evaluates the use of Markov chain process in probabilistic life cycle cost analysis and suggests further uses of the process as a design aid tool. A methodology is developed for estimating operations and support cost and expected life for reusable space transportation systems. Application of the methodology is demonstrated for the case of a hypothetical space transportation vehicle. A sensitivity analysis is carried out to explore the effects of uncertainty in key model inputs.

  18. Operational Risk Management A Practical Approach to Intelligent Data Analysis

    CERN Document Server

    Kenett, Ron

    2010-01-01

    The book will introduce modern Operational Risk (OpR) Management and illustrates the various sources of OpR assessment and OpR mitigation. This book discusses how various data sources can be integrated and analyzed and how OpR is synergetic to other risk management activities such as Financial Risk Management and Internationalization. The topics will include state of the art technology such as semantic analysis, ontology engineering, data mining and statistical analysis.

  19. 滦河流域“12.8”洪水特性及其防洪调度探析%Analysis on characteristics of“12.8 Flood” occurred in Luanhe River Basin and its flood control operation

    Institute of Scientific and Technical Information of China (English)

    杨敏; 杨学军

    2013-01-01

    In August 2012,Luanhe River Basin was impacted by both the upper trough with lower-level shear line and the Typhoon" Damrey" ——the lOth typhoon of the year respectively,whereat several strong rainfalls occurred with the precipitations about 20% more than those occurred in the same period of many years.Consequently,severe floods since 1994 happened from several rivers in the basin and then the cities and counties along the rivers were threatened at a certain scale.Through the analysis made herein on the main precipitation processes,the flood features and the characteristics of the relevant flood control operations of the" 12.8 Flood",some references are provided for strengthening the scientific and effective prevention of the flood most likely to occur in Luanhe River Basin.%2012年8月,滦河流域分别受高空槽、低空切变线及10#台风“达维”影响,发生了几场强降水过程,降雨量较多年同期偏多近2成.从而,流域多条河流发生了自1994年以来的大洪水,沿线县(市)受到一定程度洪水威胁.通过对“12.8”洪水主要降雨过程、洪水特性及调度特点分析,为今后加强滦河流域科学有效防御洪水提供参考与借鉴.

  20. Operational modal analysis in the presence of harmonic excitation

    Science.gov (United States)

    Mohanty, P.; Rixen, D. J.

    2004-02-01

    Modal operational analysis methods are procedures to identify modal parameters of structures from the response to unknown random excitations existing on buildings and in machines during operation. In many practical cases, in addition to the random loads, harmonic excitations are also present due for instance to rotating components. If the frequency of the harmonic component of the input is close to an eigenfrequency of the system, operational modal analysis procedures fail to identify the modal parameters accurately. Therefore, we propose a modification of the least-square complex exponential identification procedure to include explicitly the harmonic component. In that way, the modal parameters can be identified properly. We illustrate the efficiency of the proposed approach on the example of a beam structure excited by multi-harmonic loads superposed on random excitation.

  1. Study on laser characteristics of Ho:YLF regenerative amplifiers: Operation regimes, gain dynamics, and highly stable operation points

    Science.gov (United States)

    Kroetz, P.; Ruehl, A.; Calendron, A.-L.; Chatterjee, G.; Cankaya, H.; Murari, K.; Kärtner, F. X.; Hartl, I.; Miller, R. J. D.

    2017-04-01

    We present a comprehensive study of laser pulse amplification of Ho:YLF regenerative amplifiers (RAs) with respect to operation regimes, gain dynamics, and output pulse stability. The findings are expected to be more generic than for this specific gain material. Operation regimes are distinguished with respect to pulse energy and the appearance of pulse instability, and are studied as a function of the repetition rate, seed energy, and pump intensity. The corresponding gain dynamics are presented, identifying highly stable operation points related to high-gain build-up during pumping and high-gain depletion during pulse amplification. Such operation points are studied numerically and experimentally as a function of several parameters, thereby achieving, for our Ho:YLF RA, highly stable output pulses with measured fluctuations of only 0.19% (standard deviation).

  2. An Analysis of Current Operational Contract Support Planning Doctrine

    Science.gov (United States)

    2015-09-01

    analysis of doctrine and planning assets . The activities include interviews with various contracting and logistics professionals. F. RESEARCH...doctrine typically neglects the tangible and intangible capabilities that using OCS in missions brings to the operational and combatant commander. While... measuring the maturity of a process in practice within an organization through the issuing of surveys and measuring the responses. The model used

  3. Rethinking the process of operational research & systems analysis

    CERN Document Server

    Tomlinson, R

    1984-01-01

    Invited contributions from distinguished practitioners and methodologists of operational research and applied systems analysis which represent a true state-of-the-art and which provide, perhaps for the first time, a coherent, interlocking, set of ideas which may be considered the foundations of the subject as a science in its own right.

  4. Leaving a mark on healthcare delivery with operations analysis

    NARCIS (Netherlands)

    Vanberkel, P.T.; Zonderland, M. E.; Boucherie, R.J.; Hans, E.W.

    2012-01-01

    In the Dutch context, we see similar problems as outlined in Green’s (2012) commentary and also an increased interest by healthcare providers to use operations analysis to confront them. In this commentary, we provide our take on the same problems to extend the discussion and to highlight additional

  5. Harmonic Analysis Associated with the Generalized q-Bessel Operator

    Directory of Open Access Journals (Sweden)

    Ahmed Abouelaz

    2016-01-01

    Full Text Available In this article, we give a new harmonic analysis associated with the generalized q-Bessel operator. We introduce the generalized $q$-Bessel transform, the generalized q-Bessel translation and the generalized $q$-Bessel convolution product.

  6. An Analysis of the Waste Water Treatment Operator Occupation.

    Science.gov (United States)

    Clark, Anthony B.; And Others

    The occupational analysis contains a brief job description for the waste water treatment occupations of operator and maintenance mechanic and 13 detailed task statements which specify job duties (tools, equipment, materials, objects acted upon, performance knowledge, safety considerations/hazards, decisions, cues, and errors) and learning skills…

  7. Leaving a mark on healthcare delivery with operations analysis

    NARCIS (Netherlands)

    Vanberkel, P.T.; Golden, B.L.; Seidmann, A.; Zonderland, Maartje Elisabeth; Boucherie, Richardus J.; Hans, Elias W.

    In the Dutch context, we see similar problems as outlined in Green’s (2012) commentary and also an increased interest by healthcare providers to use operations analysis to confront them. In this commentary, we provide our take on the same problems to extend the discussion and to highlight additional

  8. Automated Frequency Domain Decomposition for Operational Modal Analysis

    DEFF Research Database (Denmark)

    Brincker, Rune; Andersen, Palle; Jacobsen, Niels-Jørgen

    2007-01-01

    The Frequency Domain Decomposition (FDD) technique is known as one of the most user friendly and powerful techniques for operational modal analysis of structures. However, the classical implementation of the technique requires some user interaction. The present paper describes an algorithm for au...

  9. A Literature Review on Operator Interface Technologies for Network Enabled Operational Environments Using Complex System Analysis

    Science.gov (United States)

    2009-05-30

    results were summarized with pros and cons of different technologies for interface design purposes. 2 Résumé Une analyse documentaire a été...Enabled Operational Environments Using Complex System Analysis (U) Une analyse documentaire sur les technologies d’interface opérateur pour les...different technologies for interface design purposes. (U) Une analyse documentaire a été menée pour examiner les technologies d’interface de pointe

  10. Operation analysis of a Chebyshev-Pantograph leg mechanism for a single DOF biped robot

    Science.gov (United States)

    Liang, Conghui; Ceccarelli, Marco; Takeda, Yukio

    2012-12-01

    In this paper, operation analysis of a Chebyshev-Pantograph leg mechanism is presented for a single degree of freedom (DOF) biped robot. The proposed leg mechanism is composed of a Chebyshev four-bar linkage and a pantograph mechanism. In contrast to general fully actuated anthropomorphic leg mechanisms, the proposed leg mechanism has peculiar features like compactness, low-cost, and easy-operation. Kinematic equations of the proposed leg mechanism are formulated for a computer oriented simulation. Simulation results show the operation performance of the proposed leg mechanism with suitable characteristics. A parametric study has been carried out to evaluate the operation performance as function of design parameters. A prototype of a single DOF biped robot equipped with two proposed leg mechanisms has been built at LARM (Laboratory of Robotics and Mechatronics). Experimental test shows practical feasible walking ability of the prototype, as well as drawbacks are discussed for the mechanical design.

  11. The autofluorescence characteristics of bacterial intracellular and extracellular substances during the operation of anammox reactor

    Science.gov (United States)

    Hou, Xiaolin; Liu, Sitong; Feng, Ying

    2017-01-01

    Anammox is a cost-effective process to treat nitrogenous wastewater. In this work, excitation–emission matrix (EEM) fluorescence spectroscopy was used to characterize the intracellular and extracellular substances of anammox sludge during reactor operation of 276 days. Four main fluorophores were identified from the intracellular substances. Two main protein-like fluorophores were identified from the extracellular substances. Correlation analysis revealed that intracellular 420 peak and humic-like peak had strong correlation with nitrogen removal rate. The two intracellular protein-like peaks had high correlation with MLVSS and MLVSS growth rate. Correlation analysis between different fluorophores discovered that the two peaks in each of these three groups—two intracellular protein-like peaks, two humic acid-like peaks and the two extracellular protein-like peaks had strong intercorrelation, which gave evidence of their homology. A specific method for fluorescence monitoring of anammox reactor were put forward, which included typical fluorescence indexes and their possible values for different operation phases. PMID:28091530

  12. Risk Analysis for Unintentional Slide Deployment During Airline Operations.

    Science.gov (United States)

    Ayra, Eduardo S; Insua, David Ríos; Castellanos, María Eugenia; Larbi, Lydia

    2015-09-01

    We present a risk analysis undertaken to mitigate problems in relation to the unintended deployment of slides under normal operations within a commercial airline. This type of incident entails relevant costs for the airline industry. After assessing the likelihood and severity of its consequences, we conclude that such risks need to be managed. We then evaluate the effectiveness of various countermeasures, describing and justifying the chosen ones. We also discuss several issues faced when implementing and communicating the proposed measures, thus fully illustrating the risk analysis process. © 2015 Society for Risk Analysis.

  13. Operation Analysis for Electrical Machinery Based on Reluctance Network

    Science.gov (United States)

    Nakamura, Kenji; Ichinokura, Osamu

    In this paper, we describe the basis of a magnetic circuit method and introduce a reluctance network analysis (RNA) proposed by authors. The RNA, which is based on the magnetic circuit method, has some suitable merits for simulating electrical machineries such as a simple analytical model, ease of coupled analysis with electrical circuits, motion, and thermal fields. In addition to these merits, a general-purpose circuit simulator like “SPICE" can be utilized as a solver. We present some applications of the RNA to operation analysis for an orthogonal-core, a switched reluctance motor, and a permanent magnet generator.

  14. Inverse spectral analysis for singular differential operators with matrix coefficients

    Directory of Open Access Journals (Sweden)

    Nour el Houda Mahmoud

    2006-02-01

    Full Text Available Let $L_alpha$ be the Bessel operator with matrix coefficients defined on $(0,infty$ by $$ L_alpha U(t = U''(t+ {I/4-alpha^2over t^2}U(t, $$ where $alpha$ is a fixed diagonal matrix. The aim of this study, is to determine, on the positive half axis, a singular second-order differential operator of $L_alpha+Q$ kind and its various properties from only its spectral characteristics. Here $Q$ is a matrix-valued function. Under suitable circumstances, the solution is constructed by means of the spectral function, with the help of the Gelfund-Levitan process. The hypothesis on the spectral function are inspired on the results of some direct problems. Also the resolution of Fredholm's equations and properties of Fourier-Bessel transforms are used here.

  15. Analysis of S-SEED's characteristics in optical switch

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This article introduces the basic structure of a symmetric self-electrooptic effect device (S-SEED), and applies the Kirchoff's current law and a purely equivalent capacitive model, to analyze S-SEED's switch characteristics. Linear approximation and N-segment approximation are utilized to obtain S-SEED's voltage-time (V-T) and characteristics. Theoretical analysis is verified by simulations, and the results demonstrate that the precision of S-SEED's switch time can satisfy the requirement in applications with linear approximation. Moreover, the simulations compare S-SEED's switch characteristics with different input powers and input contrast ratios, which reveal that increasing input contrast ratio is an effective way to improve S-SEED's switch characteristics.

  16. Operations other than war: Requirements for analysis tools research report

    Energy Technology Data Exchange (ETDEWEB)

    Hartley, D.S. III

    1996-12-01

    This report documents the research effort to determine the requirements for new or improved analysis tools to support decisions at the strategic and operational levels for military Operations Other than War (OOTW). The work was performed for the Commander in Chief, U.S. Pacific Command (USCINCPAC). The data collection was based on workshops attended by experts in OOTWs: analysis personnel from each of the Combatant Commands, the Services, the Office of the Secretary of Defense (OSD), the Joint Staff, and other knowledgeable personnel. Further data were gathered from other workshops and conferences and from the literature. The results of this research begin with the creation of a taxonomy of OOTWs: categories of operations, attributes of operations, and tasks requiring analytical support. The tasks are connected to the Joint Staff`s Universal Joint Task List (UJTL). Historical OOTWs are analyzed to produce frequency distributions by category and responsible CINC. The analysis products are synthesized into a list of requirements for analytical tools and definitions of the requirements. The report concludes with a timeline or roadmap for satisfying the requirements.

  17. Modeling, Analysis and Design of Feedback Operational Amplifier for Undergraduate Studies in Electrical Engineering

    Directory of Open Access Journals (Sweden)

    Han Yang

    2012-12-01

    Full Text Available The analog electronics is a challenging subject for undergraduate students in electrical engineering, due to the complex combination of many previous subjects, such as linear circuit analysis, signal and system, linear control theory and some sort of mathematics. This paper presents the modeling, analysis and design of the operational amplifier, which is used as benchmark system for analog electronics, for undergraduate studies in electrical engineering. Followed by the introduction of the operation amplifier circuit, the design of feedback network for the operational amplifier using MATLAB is presented. The bandwidth and sensitivity analysis for the feedback control loop are also discussed. In order to enhance the stability margin and dynamic characteristics of the operational amplifier, the lead compensator is designed for the feedback loop by adding capacitive component to the feedback resistive network. The presented analysis and design method of the operational amplifier by using MATLAB/SIMULINK can be highly effective to compliment the classroom teaching for circuit design courses for undergraduate studies in electrical engineering.

  18. Operational Modal Analysis of Wind Turbine Speed-increase Gearbox

    Directory of Open Access Journals (Sweden)

    LI Yafeng

    2013-11-01

    Full Text Available Speed increase transmission gear box is the primary vibration and noise source of wind turbine, Operational modal method was adopted to collect impact data and response data of each point based on the gearbox test model. ANSYS finite element model is established to simulate the wind turbine gearbox. Then the modal frequencies of the two methods were compared to ensure the test model is correct. The results show that operational modal method can be applied in wind turbine gearbox modal analysis and it has important guiding significance to gearbox fault diagnosis and reliability and maintainability improving.  

  19. Silicon avalanche photodiode operation and lifetime analysis for small satellites.

    Science.gov (United States)

    Tan, Yue Chuan; Chandrasekara, Rakhitha; Cheng, Cliff; Ling, Alexander

    2013-07-15

    Silicon avalanche photodiodes (APDs) are sensitive to operating temperature fluctuations and are also susceptible to radiation flux expected in satellite-based quantum experiments. We introduce a low power voltage adjusting mechanism to overcome the effects of in-orbit temperature fluctuations. We also present data on the performance of Si APDs after irradiation (γ-ray and proton beam). Combined with an analysis of expected orbital irradiation, we propose that a Si APD in a 400 km equatorial orbit may operate beyond the lifetime of the satellite.

  20. Silicon avalanche photodiode operation and lifetime analysis for small satellites

    CERN Document Server

    Tan, Yue Chuan; Cheng, Cliff; Ling, Alexander

    2013-01-01

    Silicon avalanche photodiodes (APDs) are sensitive to operating temperature fluctuations and are also susceptible to radiation flux expected in satellite-based quantum experiments. We introduce a low power voltage adjusting mechanism to overcome the effects of in-orbit temperature fluctuations. We also present data on the performance of Si APDs after irradiation (gamma-ray and proton beam). Combined with an analysis of expected orbital irradiation, we propose that a Si APD in a 400 km equatorial orbit may operate beyond the lifetime of the satellite.

  1. User's operating procedures. Volume 2: Scout project financial analysis program

    Science.gov (United States)

    Harris, C. G.; Haris, D. K.

    1985-01-01

    A review is presented of the user's operating procedures for the Scout Project Automatic Data system, called SPADS. SPADS is the result of the past seven years of software development on a Prime mini-computer located at the Scout Project Office, NASA Langley Research Center, Hampton, Virginia. SPADS was developed as a single entry, multiple cross-reference data management and information retrieval system for the automation of Project office tasks, including engineering, financial, managerial, and clerical support. This volume, two (2) of three (3), provides the instructions to operate the Scout Project Financial Analysis program in data retrieval and file maintenance via the user friendly menu drivers.

  2. Fractal Characteristics Analysis of Blackouts in Interconnected Power Grid

    DEFF Research Database (Denmark)

    Wang, Feng; Li, Lijuan; Li, Canbing

    2017-01-01

    The power failure models are a key to understand the mechanism of large scale blackouts. In this letter, the similarity of blackouts in interconnected power grids (IPGs) and their sub-grids is discovered by the fractal characteristics analysis to simplify the failure models of the IPG. The distri......The power failure models are a key to understand the mechanism of large scale blackouts. In this letter, the similarity of blackouts in interconnected power grids (IPGs) and their sub-grids is discovered by the fractal characteristics analysis to simplify the failure models of the IPG....... The distribution characteristics of blackouts in various sub-grids are demonstrated based on the Kolmogorov-Smirnov (KS) test. The fractal dimensions (FDs) of the IPG and its sub-grids are then obtained by using the KS test and the maximum likelihood estimation (MLE). The blackouts data in China were used...

  3. Effects of design and operating variables on process characteristics in a methane discharge: a numerical study

    Science.gov (United States)

    Bera, K.; Farouk, B.; Lee, Y. H.

    2001-05-01

    A self-consistent two-dimensional radio frequency capacitively coupled glow discharge model has been developed in cylindrical coordinates for a methane discharge using a fluid model. The objective of the study is to identify the effects of design and operating variables of the reactor on the process characteristics such as the deposition rate, uniformity and the quality of the diamond-like-carbon film. The simulations provide insights to charged species dynamics and investigate their effects on the plasma process for a depositing methane discharge. The model includes continuity equations for electrons and positive and negative ions, and energy equation for electrons. Swarm data as a function of electron energy are provided as input to the model. The model predicts the electron density, ion density, and their fluxes and energies to the cathode. The roles of electrons, dominating ions and radicals in a capacitively coupled discharge are investigated. The radical and neutral densities in the discharge are calculated using a gas phase chemistry model. The diamond-like-carbon thin-film deposition rate is predicted using surface chemistry model. The gas phase chemistry model considers diffusion of radicals and neutrals along with creation and loss terms. The surface deposition/etching process involves adsorption-desorption, adsorption layer reaction, ion stitching, direct ion incorporation, etching and carbon sputtering. A systematic parametric study of plasma processing has been performed to identify process parameters to obtain better film deposition/etching on a wafer. The present work shows how plasma equipment simulation can be used for the practical investigation and optimization of a plasma-assisted chemical vapour deposition process. The simultaneous treatment of plasma dynamics and surface processes enables a very precise prediction of the process characteristics in terms of the film deposition rate, uniformity and the quality as functions of discharge control

  4. COMBUSTION CHARACTERISTICS OF DIESEL ENGINE OPERATING ON JATROPHA OIL METHYL ESTER

    Directory of Open Access Journals (Sweden)

    Doddayaraganalu Amasegoda Dhananjaya

    2010-01-01

    Full Text Available Fuel crisis because of dramatic increase in vehicular population and environmental concerns have renewed interest of scientific community to look for alternative fuels of bio-origin such as vegetable oils. Vegetable oils can be produced from forests, vegetable oil crops, and oil bearing biomass materials. Non-edible vegetable oils such as jatropha oil, linseed oil, mahua oil, rice bran oil, karanji oil, etc., are potentially effective diesel substitute. Vegetable oils have reasonable energy content. Biodiesel can be used in its pure form or can be blended with diesel to form different blends. It can be used in diesel engines with very little or no engine modifications. This is because it has combustion characteristics similar to petroleum diesel. The current paper reports a study carried out to investigate the combustion, performance and emission characteristics of jatropha oil methyl ester and its blend B20 (80% petroleum diesel and 20% jatropha oil methyl ester and diesel fuel on a single-cylinder, four-stroke, direct injections, water cooled diesel engine. This study gives the comparative measures of brake thermal efficiency, brake specific energy consumption, smoke opacity, HC, NOx, ignition delay, cylinder peak pressure, and peak heat release rates. The engine performance in terms of higher thermal efficiency and lower emissions of blend B20 fuel operation was observed and compared with jatropha oil methyl ester and petroleum diesel fuel for injection timing of 20° bTDC, 23° bTDC and 26° bTDC at injection opening pressure of 220 bar.

  5. Analysis of the Characteristics in the Meudon Constrained Evolution Scheme

    Energy Technology Data Exchange (ETDEWEB)

    Cordero-Carrion, I [Departamento de Astronomia y Astrofisica, Universidad de Valencia, Valencia (Spain); Ibanez, J M [Departamento de Astronomia y Astrofisica, Universidad de Valencia, Valencia (Spain); Jaramillo, J L [Instituto de Astrofisica de Andalucia (IAA-CSIC), Apartado 3004 18080 Granada (Spain); Gourgoulhon, E [Laboratoire de l' Univers et des Theories (LUTH), Observatoire de Paris, 92195 Meudon (France)

    2007-05-15

    A first analysis of the characteristics associated with the evolving modes in the constraint evolution scheme proposed by the Meudon group in 2004 is presented. The system is written in a first-order hyperbolic form and a so-called generalized Dirac gauge is considered. Applications to inner boundary conditions in an excised approach to black hole evolutions are discussed.

  6. IMPROVEMENT OF BUS OPERATIONAL CHARACTERISTICS WHILE USING INTEGRATED CONTROL OF SUSPENSION AND TRANSMISSION

    Directory of Open Access Journals (Sweden)

    V. V. Mikhailau

    2016-01-01

    Full Text Available Semi-natural tests for active pneumatic suspension of a 18-tonne tourist bus with the system of automatic body stabilization of the mobile machine and feed-back coupling according to kinematics parameter. The test have been executed in the cases when the bus is stocked with an automatic hydro-mechanical transmission in the process of speed picking up, gear-changing or road braking which is assigned by accidental road humps. A computer simulation of dynamic structures in combination with virtual devices and real objects (HIL – Hardware-in-the-Loop Simulation has been carried in the paper. Personal computers, software, programmed logic controller, frequency generator, solenoid-operated valve have been used for the investigation process. The paper proposes an unconventional method for improvement operational characteristics which is based on integrated control of a suspension and automatic hydro-mechanical transmission. A mathematical model includes systems of automatic transmission, suspension and module for generation of accidental road humps. The model has been considered as a basis for semi-natural laboratory bench with industrially-manufactured controller, other components of automatic systems and standard control organs. The most efficient method for body stabilization is control of the suspension according to the parameter of angular rate during vertical turn of an automobile’s center line with a turning point in the center of mass. The developed algorithm and stabilization system according to angular rate of body’s center line turning have made it possible to improve dynamics of the bus while making gear-changing and to reduce fuel consumption during starting-up and speed picking-up processes. During the braking process such system simultaneously decreases oscillation amplitude of some parameters more than two-fold.

  7. [Quantitative spectrum analysis of characteristic gases of spontaneous combustion coal].

    Science.gov (United States)

    Liang, Yun-Tao; Tang, Xiao-Jun; Luo, Hai-Zhu; Sun, Yong

    2011-09-01

    Aimed at the characteristics of spontaneous combustion gas such as a variety of gases, lou limit of detection, and critical requirement of safety, Fourier transform infrared (FTIR) spectral analysis is presented to analyze characteristic gases of spontaneous combustion In this paper, analysis method is introduced at first by combing characteristics of absorption spectra of analyte and analysis requirement. Parameter setting method, sample preparation, feature variable abstract and analysis model building are taken into consideration. The methods of sample preparation, feature abstraction and analysis model are introduced in detail. And then, eleven kinds of gases were tested with Tensor 27 spectrometer. CH4, C2H6, C3H8, iC4H10, nC4H10, C2 H4, C3 H6, C3 H2, SF6, CO and CO2 were included. The optical path length was 10 cm while the spectra resolution was set as 1 cm(-1). The testing results show that the detection limit of all analytes is less than 2 x 10(-6). All the detection limits fit the measurement requirement of spontaneous combustion gas, which means that FTIR may be an ideal instrument and the analysis method used in this paper is competent for spontaneous combustion gas measurement on line.

  8. Operation Characteristics and Manufacturing Essentials of Traction Transformer%牵引变压器运行特性及制造要点

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    Through the analysis of operation characteristics of electrical railway system ,the key points in design and manufacturing process of traction transformers are summarized .%  通过分析电气化铁路系统的运行特点,总结了牵引变压器的设计、工艺要点和制造中需采取的措施。

  9. Operating cost analysis of anaesthesia: Activity based costing (ABC analysis

    Directory of Open Access Journals (Sweden)

    Majstorović Branislava M.

    2011-01-01

    Full Text Available Introduction. Cost of anaesthesiology represent defined measures to determine a precise profile of expenditure estimation of surgical treatment, which is important regarding planning of healthcare activities, prices and budget. Objective. In order to determine the actual value of anaestesiological services, we started with the analysis of activity based costing (ABC analysis. Methods. Retrospectively, in 2005 and 2006, we estimated the direct costs of anestesiological services (salaries, drugs, supplying materials and other: analyses and equipment. of the Institute of Anaesthesia and Resuscitation of the Clinical Centre of Serbia. The group included all anesthetized patients of both sexes and all ages. We compared direct costs with direct expenditure, “each cost object (service or unit” of the Republican Health-care Insurance. The Summary data of the Departments of Anaesthesia documented in the database of the Clinical Centre of Serbia. Numerical data were utilized and the numerical data were estimated and analyzed by computer programs Microsoft Office Excel 2003 and SPSS for Windows. We compared using the linear model of direct costs and unit costs of anaesthesiological services from the Costs List of the Republican Health-care Insurance. Results. Direct costs showed 40% of costs were spent on salaries, (32% on drugs and supplies, and 28% on other costs, such as analyses and equipment. The correlation of the direct costs of anaestesiological services showed a linear correlation with the unit costs of the Republican Healthcare Insurance. Conclusion. During surgery, costs of anaesthesia would increase by 10% the surgical treatment cost of patients. Regarding the actual costs of drugs and supplies, we do not see any possibility of costs reduction. Fixed elements of direct costs provide the possibility of rationalization of resources in anaesthesia.

  10. Investigation on Flame Characteristics and Burner Operability Issues of Oxy-Fuel Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Choudhuri, Ahsan [Univ. Of Texas, El Paso, TX (United States)

    2013-09-30

    Oxy-fuel combustion has been used previously in a wide range of industrial applications. Oxy- combustion is carried out by burning a hydrocarbon fuel with oxygen instead of air. Flames burning in this configuration achieve higher flame temperatures which present opportunities for significant efficiency improvements and direct capture of CO2 from the exhaust stream. In an effort to better understand and characterize the fundamental flame characteristics of oxy-fuel combustion this research presents the experimental measurements of flame stability of various oxyfuel flames. Effects of H2 concentration, fuel composition, exhaust gas recirculation ratio, firing inputs, and burner diameters on the flame stability of these fuels are discussed. Effects of exhaust gas recirculation i.e. CO2 and H2O (steam) acting as diluents on burner operability are also presented. The roles of firing input on flame stability are then analyzed. For this study it was observed that many oxy-flames did not stabilize without exhaust gas recirculation due to their higher burning velocities. In addition, the stability regime of all compositions was observed to decrease as the burner diameter increased. A flashback model is also presented, using the critical velocity gradient gF) values for CH4-O2-CO2 flames. The second part of the study focuses on the experimental measurements of the flow field characteristics of premixed CH4/21%O2/79%N2 and CH4/38%O2/72%CO2 mixtures at constant firing input of 7.5 kW, constant, equivalence ratio of 0.8, constant swirl number of 0.92 and constant Reynolds Numbers. These measurements were taken in a swirl stabilized combustor at atmospheric pressure. The flow field visualization using Particle Imaging Velocimetry (PIV) technique is implemented to make a better understanding of the turbulence characteristics of

  11. Olive mill wastewater characteristics: modelling and statistical analysis

    Directory of Open Access Journals (Sweden)

    Martins-Dias, Susete

    2004-09-01

    Full Text Available A synthesis of the work carried out on Olive Mill Wastewater (OMW characterisation is given, covering articles published over the last 50 years. Data on OMW characterisation found in the literature are summarised and correlations between them and with phenolic compounds content are sought. This permits the characteristics of an OMW to be estimated from one simple measurement: the phenolic compounds concentration. A model based on OMW characterisations accounting 6 countries was developed along with a model for Portuguese OMW. The statistical analysis of the correlations obtained indicates that Chemical Oxygen Demand of a given OMW is a second-degree polynomial function of its phenolic compounds concentration. Tests to evaluate the regressions significance were carried out, based on multivariable ANOVA analysis, on visual standardised residuals distribution and their means for confidence levels of 95 and 99 %, validating clearly these models. This modelling work will help in the future planning, operation and monitoring of an OMW treatment plant.Presentamos una síntesis de los trabajos realizados en los últimos 50 años relacionados con la caracterización del alpechín. Realizamos una recopilación de los datos publicados, buscando correlaciones entre los datos relativos al alpechín y los compuestos fenólicos. Esto permite la determinación de las características del alpechín a partir de una sola medida: La concentración de compuestos fenólicos. Proponemos dos modelos, uno basado en datos relativos a seis países y un segundo aplicado únicamente a Portugal. El análisis estadístico de las correlaciones obtenidas indica que la demanda química de oxígeno de un determinado alpechín es una función polinómica de segundo grado de su concentración de compuestos fenólicos. Se comprobó la significancia de esta correlación mediante la aplicación del análisis multivariable ANOVA, y además se evaluó la distribución de residuos y sus

  12. Application of human error analysis to aviation and space operations

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, W.R.

    1998-03-01

    For the past several years at the Idaho National Engineering and Environmental Laboratory (INEEL) the authors have been working to apply methods of human error analysis to the design of complex systems. They have focused on adapting human reliability analysis (HRA) methods that were developed for Probabilistic Safety Assessment (PSA) for application to system design. They are developing methods so that human errors can be systematically identified during system design, the potential consequences of each error can be assessed, and potential corrective actions (e.g. changes to system design or procedures) can be identified. The primary vehicle the authors have used to develop and apply these methods has been a series of projects sponsored by the National Aeronautics and Space Administration (NASA) to apply human error analysis to aviation operations. They are currently adapting their methods and tools of human error analysis to the domain of air traffic management (ATM) systems. Under the NASA-sponsored Advanced Air Traffic Technologies (AATT) program they are working to address issues of human reliability in the design of ATM systems to support the development of a free flight environment for commercial air traffic in the US. They are also currently testing the application of their human error analysis approach for space flight operations. They have developed a simplified model of the critical habitability functions for the space station Mir, and have used this model to assess the affects of system failures and human errors that have occurred in the wake of the collision incident last year. They are developing an approach so that lessons learned from Mir operations can be systematically applied to design and operation of long-term space missions such as the International Space Station (ISS) and the manned Mars mission.

  13. An Analysis Methodology for Stochastic Characteristic of Volumetric Error in Multiaxis CNC Machine Tool

    Directory of Open Access Journals (Sweden)

    Qiang Cheng

    2013-01-01

    Full Text Available Traditional approaches about error modeling and analysis of machine tool few consider the probability characteristics of the geometric error and volumetric error systematically. However, the individual geometric error measured at different points is variational and stochastic, and therefore the resultant volumetric error is aslo stochastic and uncertain. In order to address the stochastic characteristic of the volumetric error for multiaxis machine tool, a new probability analysis mathematical model of volumetric error is proposed in this paper. According to multibody system theory, a mean value analysis model for volumetric error is established with consideration of geometric errors. The probability characteristics of geometric errors are obtained by statistical analysis to the measured sample data. Based on probability statistics and stochastic process theory, the variance analysis model of volumetric error is established in matrix, which can avoid the complex mathematics operations during the direct differential. A four-axis horizontal machining center is selected as an illustration example. The analysis results can reveal the stochastic characteristic of volumetric error and are also helpful to make full use of the best workspace to reduce the random uncertainty of the volumetric error and improve the machining accuracy.

  14. Harmonic component detection: Optimized Spectral Kurtosis for operational modal analysis

    Science.gov (United States)

    Dion, J.-L.; Tawfiq, I.; Chevallier, G.

    2012-01-01

    This work is a contribution in the field of Operational Modal Analysis to identify the modal parameters of mechanical structures using only measured responses. The study deals with structural responses coupled with harmonic components amplitude and frequency modulated in a short range, a common combination for mechanical systems with engines and other rotating machines in operation. These harmonic components generate misleading data interpreted erroneously by the classical methods used in OMA. The present work attempts to differentiate maxima in spectra stemming from harmonic components and structural modes. The detection method proposed is based on the so-called Optimized Spectral Kurtosis and compared with others definitions of Spectral Kurtosis described in the literature. After a parametric study of the method, a critical study is performed on numerical simulations and then on an experimental structure in operation in order to assess the method's performance.

  15. Environmental Quality Information Analysis Center (EQIAC) operating procedures handbook

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, T.E. (Florida Univ., Gainesville, FL (United States)); Das, S. (Oak Ridge National Lab., TN (United States))

    1992-08-01

    The Operating Procedures Handbook of the Environmental Quality Information Analysis Center (EQIAC) is intended to be kept current as EQIAC develops and evolves. Its purpose is to provide a comprehensive guide to the mission, infrastructure, functions, and operational procedures of EQIAC. The handbook is a training tool for new personnel and a reference manual for existing personnel. The handbook will be distributed throughout EQIAC and maintained in binders containing current dated editions of the individual sections. The handbook will be revised at least annually to reflect the current structure and operational procedures of EQIAC. The EQIAC provides information on environmental issues such as compliance, restoration, and environmental monitoring do the Air Force and DOD contractors.

  16. Power Consumption Analysis of Operating Systems for Wireless Sensor Networks

    Science.gov (United States)

    Lajara, Rafael; Pelegrí-Sebastiá, José; Perez Solano, Juan J.

    2010-01-01

    In this paper four wireless sensor network operating systems are compared in terms of power consumption. The analysis takes into account the most common operating systems—TinyOS v1.0, TinyOS v2.0, Mantis and Contiki—running on Tmote Sky and MICAz devices. With the objective of ensuring a fair evaluation, a benchmark composed of four applications has been developed, covering the most typical tasks that a Wireless Sensor Network performs. The results show the instant and average current consumption of the devices during the execution of these applications. The experimental measurements provide a good insight into the power mode in which the device components are running at every moment, and they can be used to compare the performance of different operating systems executing the same tasks. PMID:22219688

  17. Power consumption analysis of operating systems for wireless sensor networks.

    Science.gov (United States)

    Lajara, Rafael; Pelegrí-Sebastiá, José; Perez Solano, Juan J

    2010-01-01

    In this paper four wireless sensor network operating systems are compared in terms of power consumption. The analysis takes into account the most common operating systems--TinyOS v1.0, TinyOS v2.0, Mantis and Contiki--running on Tmote Sky and MICAz devices. With the objective of ensuring a fair evaluation, a benchmark composed of four applications has been developed, covering the most typical tasks that a Wireless Sensor Network performs. The results show the instant and average current consumption of the devices during the execution of these applications. The experimental measurements provide a good insight into the power mode in which the device components are running at every moment, and they can be used to compare the performance of different operating systems executing the same tasks.

  18. Enzymatic AND logic gates operated under conditions characteristic of biomedical applications.

    Science.gov (United States)

    Melnikov, Dmitriy; Strack, Guinevere; Zhou, Jian; Windmiller, Joshua Ray; Halámek, Jan; Bocharova, Vera; Chuang, Min-Chieh; Santhosh, Padmanabhan; Privman, Vladimir; Wang, Joseph; Katz, Evgeny

    2010-09-23

    Experimental and theoretical analyses of the lactate dehydrogenase and glutathione reductase based enzymatic AND logic gates in which the enzymes and their substrates serve as logic inputs are performed. These two systems are examples of the novel, previously unexplored class of biochemical logic gates that illustrate potential biomedical applications of biochemical logic. They are characterized by input concentrations at logic 0 and 1 states corresponding to normal and pathophysiological conditions. Our analysis shows that the logic gates under investigation have similar noise characteristics. Both significantly amplify random noise present in inputs; however, we establish that for realistic widths of the input noise distributions, it is still possible to differentiate between the logic 0 and 1 states of the output. This indicates that reliable detection of pathophysiological conditions is indeed possible with such enzyme logic systems.

  19. MAIN CHARACTERISTICS OF COMPANIES USING SERVICE ORIENTED ARCHITECTURE (SOA AND OF THEIR OPERATION CONTEXT

    Directory of Open Access Journals (Sweden)

    Alfonso Duran Heras

    2008-12-01

    Full Text Available The aim of this article is to establish the main characteristics of the organizations that have successfully implemented information systems based on Service Oriented Architecture (SOA. Their environmental circumstances have also been studied. To achieve this objective, a SOA bibliographic review has been carried out, encompassing an analysis of 25 real cases in which different SOA applications were successfully implemented. All these cases were published between 2.001 and 2.007. The conclusions of this article can be briefly summarized as follows: SOA is well suited for organizations that rely on important legacy systems, whose performance is hindered by the lack of integration and flexibility of their computer architectures. These organizations therefore need to improve such architectures rather than replace them by new systems; SOA is being used by organizations that need to integrate their systems with those of their supply chain partners; SOA solutions provide support for the use of Web technologies.

  20. Operating characteristics of a 0.87 kW-hr flywheel energy storage module

    Science.gov (United States)

    Loewenthal, S. H.; Scibbe, H. W.; Parker, R. D.; Zaretsky, E. V.

    1985-01-01

    Discussion is given of the design and loss characteristics of 0.87 kW-hr (peak) flywheel energy storage module suitable for aerospace and automotive applications. The maraging steel flywheel rotor, a 46-cm- (18-in-) diameter, 58-kg (128-lb) tapered disk, delivers 0.65 kW-hr of usable energy between operating speeds of 10,000 and 20,000 rpm. The rotor is supported by 20- and 25-mm bore diameter, deep-groove ball bearings, lubricated by a self-replenishing wick type lubrication system. To reduce aerodynamic losses, the rotor housing was evacuated to vacuum levels from 40 to 200 millitorr. Dynamic rotor instabilities uncovered during testing necessitated the use of an elastometric-bearing damper to limit shaft excursions. Spindown losses from bearing, seal, and aerodynamic drag at 50 millitorr typically ranged from 64 to 193 W at 10,000 and 20,000 rpm, respectively. Discharge efficiency of the flywheel system exceeded 96 percent at torque levels greater than 21 percent of rated torque.

  1. Operating characteristics of a qualitative troponin assay for the diagnosis of acute coronary syndrome.

    Science.gov (United States)

    Farsi, Davood; Pishbin, Elham; Abbasi, Saeed; Hafezimoghadam, Peyman; Fathi, Marzieh; Zare, Mohammad Amin

    2013-04-01

    The troponin I serum level is widely used in acute coronary syndrome patients for their classification. The qualitative assay is faster and more available than the quantitative assay. The objective was to determine the operating characteristics of a qualitative troponin I assay compared with a quantitative method. This is a prospective observational study and patients suspected to have acute coronary syndrome were enrolled. A rapid troponin I test and a quantitative assay were carried out for each patient on arrival and 6 h after admission. A total of 262 patients were enrolled. The degree of agreement between the second rapid qualitative and quantitative troponin I was excellent (κ=0.946; 95% confidence interval, 0.903-0.989). The sensitivity, specificity, negative predictive value, and positive predictive value of the rapid qualitative troponin I test were 92.6, 100, 96.8, and 100%, respectively. In conclusion, this study reveals an excellent agreement between quantitative and qualitative bedside assays 6 h after admission in a sample of Iranian patients in the emergency department.

  2. Application of Receiver Operating Characteristic (ROC Curves for Explosives Detection Using Different Sampling and Detection Techniques

    Directory of Open Access Journals (Sweden)

    Mimy Young

    2013-12-01

    Full Text Available Reported for the first time are receiver operating characteristic (ROC curves constructed to describe the performance of a sorbent-coated disk, planar solid phase microextraction (PSPME unit for non-contact sampling of a variety of volatiles. The PSPME is coupled to ion mobility spectrometers (IMSs for the detection of volatile chemical markers associated with the presence of smokeless powders, model systems of explosives containing diphenylamine (DPA, 2,4-dinitrotoluene (2,4-DNT and nitroglycerin (NG as the target analytes. The performance of the PSPME-IMS was compared with the widely accepted solid-phase microextraction (SPME, coupled to a GC-MS. A set of optimized sampling conditions for different volume containers (1–45 L with various sample amounts of explosives, were studied in replicates (n = 30 to determine the true positive rates (TPR and false positive detection rates (FPR for the different scenarios. These studies were obtained in order to construct the ROC curves for two IMS instruments (a bench-top and field-portable system and a bench top GC-MS system in low and high clutter environments. Both static and dynamic PSPME sampling were studied in which 10–500 mg quantities of smokeless powders were detected within 10 min of static sampling and 1 min of dynamic sampling.

  3. Multivariate normally distributed biomarkers subject to limits of detection and receiver operating characteristic curve inference.

    Science.gov (United States)

    Perkins, Neil J; Schisterman, Enrique F; Vexler, Albert

    2013-07-01

    Biomarkers are of ever-increasing importance to clinical practice and epidemiologic research. Multiple biomarkers are often measured per patient. Measurement of true biomarker levels is limited by laboratory precision, specifically measuring relatively low, or high, biomarker levels resulting in undetectable levels below, or above, a limit of detection (LOD). Ignoring these missing observations or replacing them with a constant are methods commonly used although they have been shown to lead to biased estimates of several parameters of interest, including the area under the receiver operating characteristic (ROC) curve and regression coefficients. We developed asymptotically consistent, efficient estimators, via maximum likelihood techniques, for the mean vector and covariance matrix of multivariate normally distributed biomarkers affected by LOD. We also developed an approximation for the Fisher information and covariance matrix for our maximum likelihood estimations (MLEs). We apply these results to an ROC curve setting, generating an MLE for the area under the curve for the best linear combination of multiple biomarkers and accompanying confidence interval. Point and confidence interval estimates are scrutinized by simulation study, with bias and root mean square error and coverage probability, respectively, displaying behavior consistent with MLEs. An example using three polychlorinated biphenyls to classify women with and without endometriosis illustrates how the underlying distribution of multiple biomarkers with LOD can be assessed and display increased discriminatory ability over naïve methods. Properly addressing LODs can lead to optimal biomarker combinations with increased discriminatory ability that may have been ignored because of measurement obstacles. Published by Elsevier Inc.

  4. Receiver Operating Characteristic (ROC to Determine Cut-Off Points of Biomarkers in Lung Cancer Patients

    Directory of Open Access Journals (Sweden)

    Heidi L. Weiss

    2004-01-01

    Full Text Available The role of biomarkers in disease prognosis continues to be an important investigation in many cancer studies. In order for these biomarkers to have practical application in clinical decision making regarding patient treatment and follow-up, it is common to dichotomize patients into those with low vs. high expression levels. In this study, receiver operating characteristic (ROC curves, area under the curve (AUC of the ROC, sensitivity, specificity, as well as likelihood ratios were calculated to determine levels of growth factor biomarkers that best differentiate lung cancer cases versus control subjects. Selected cut-off points for p185erbB-2 and EGFR membrane appear to have good discriminating power to differentiate control tissues versus uninvolved tissues from patients with lung cancer (AUC = 89% and 90%, respectively; while AUC increased to at least 90% for selected cut-off points for p185erbB-2 membrane, EGFR membrane, and FASE when comparing between control versus carcinoma tissues from lung cancer cases. Using data from control subjects compared to patients with lung cancer, we presented a simple and intuitive approach to determine dichotomized levels of biomarkers and validated the value of these biomarkers as surrogate endpoints for cancer outcome.

  5. Characteristics associated with organizational independence in consumer-operated service organizations.

    Science.gov (United States)

    Tanenbaum, Sandra J

    2011-01-01

    This research compares two types of consumer organizations in one state in order to explore the significance of organizational independence for internal structure/operations and external relationships. The first type, consumeroperated service organizations (COSOs), are independent and fully self-governing; the second are peer-support service organizations (PSSOs), which are part of larger non-consumer entities. Mail surveys were completed by COSO and PSSO directors of a geographically representative sample of organizations; telephone interviews were conducted with a sub-sample. Owing to small sample size, matched COSO-PSSO pairs were analyzed using non-parametric statistics. COSOs and PSSOs are similar in some ways, e.g., types of services provided, but significantly different on internal variables, such as budget size, and external variables, such as number of relationships with community groups. Organizational independence appears to be a significant characteristic for consumer service organizations and should be encouraged by funders and among participants. Funders might establish administrative and/or programmatic measures to support consumer organizations that are independent or moving toward independence; their participants would also benefit from the provision, by authorities or advocates, of materials to guide organizations toward, for example, 501(c)3 status.

  6. The effect of maximum open height on operating characteristics of polymer injected pump poppet valve

    Science.gov (United States)

    Zhang, S. C.; Chen, X. D.; Deng, H. Y.

    2012-11-01

    Reciprocating polymer injected pump is the key injection equipment of tertiary oil recovery, the poppet valve in it exists the problem of large vibration noise, low efficiency and short life when transportation high viscosity medium. So the CFD technique is adopted to simulate and analyze the inner flow fields of fluid end poppet valve. According to the practical structure of the poppet valve, a simplified 2D axis-symmetry geometry model of the flow field is established. Combined with pump speed, plunger stroke and plunger diameter, given the boundary condition of the inlet valve, then the numerical simulation of flow field under six different maximum open heights is done depending on software Fluent. The relationship between open height to valve gap flow velocity, hydraulic loss and lag angle is obtained. The results indicate that, with the increase of open height, the valve gap flow velocity decreases, inlet outlet pressure differential decreases and hydraulic loss decreases. But the lag angle is continuously increasing with the increase of maximum open height, the valve has a good work performance when the open height is 1, 1.5, 2, 2.5, 3mm, but when it reaches 3.5mm, the valve performance becomes poor. The study can offer certain reference to understand operating characteristics of poppet valve, help to reduce the hydraulic losses and raise volume efficiency of the pump.

  7. Operational characteristics of mixed traffic flow under bi-directional environment using cellular automaton

    Directory of Open Access Journals (Sweden)

    Zhenke Luo

    2014-12-01

    Full Text Available Mixed traffic flow composed of autos and non-autos widely exists in developing countries and areas. To investigate the operational characteristics of the mixed traffic flow consisting of vehicles in different types (large vehicles, cas, and bicycles, we develop a cellular automaton model to replicate the travel behaviors on a bi-directional road segment with respect to the physical and mechanic ftures of différent vehicle types. By implementing the eesential parameters calibrated through the field data collection, a numerical study is carried out considering the variation in volume, density, and velocity with different compositions of mixed traffic flows. The primary findings include: the average velocity of traffic flow and total volume decrease 60% and 30% after incorporating 10% bicycles, respectively; the phenomenon of double-summit in terms of the total volume appears when the proportion of bicycle is beyond 60%; the maximal total volume starts to recover when the proportion of bicycle is higher than 10 %.

  8. Characteristic parameters and operational curves of γ-Al2O3 nanofiltration membranes

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The γ-Al2O3 nanofiltration membranes were manufactured by the sol-gel technique. The result of N2 adsorption and desorption test indicates that the characteristic parameters of the membranes: BJH desorption average pore diameter, BJH desorption cumulative volume of pores and BET surface area are about 3.9 nm, 0.33 cm3/g and 245 m2/g respectively, and the pore size distribution is very narrow. The operational curves of γ-Al2O3 nanofiltration membranes of the Ca2+ retention rate vs the trans-membrane pressure, feed concentration of solution treated and pH of solution treated were studied for the first time. It is found that the retention rate for Ca2+ increases with the transmembrane pressure increasing and decreases with the feed concentration of CaCl2 solution increasing. The retention of Ca2+ is very much dependent on the pH of the solution. Minimal Ca2+ retention rate is found at the isoelectric point (pH = 7.5).

  9. Visualization of the significance of Receiver Operating Characteristics based on confidence ellipses

    Science.gov (United States)

    Sarlis, Nicholas V.; Christopoulos, Stavros-Richard G.

    2014-03-01

    The Receiver Operating Characteristics (ROC) is used for the evaluation of prediction methods in various disciplines like meteorology, geophysics, complex system physics, medicine etc. The estimation of the significance of a binary prediction method, however, remains a cumbersome task and is usually done by repeating the calculations by Monte Carlo. The FORTRAN code provided here simplifies this problem by evaluating the significance of binary predictions for a family of ellipses which are based on confidence ellipses and cover the whole ROC space. Catalogue identifier: AERY_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AERY_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 11511 No. of bytes in distributed program, including test data, etc.: 72906 Distribution format: tar.gz Programming language: FORTRAN. Computer: Any computer supporting a GNU FORTRAN compiler. Operating system: Linux, MacOS, Windows. RAM: 1Mbyte Classification: 4.13, 9, 14. Nature of problem: The Receiver Operating Characteristics (ROC) is used for the evaluation of prediction methods in various disciplines like meteorology, geophysics, complex system physics, medicine etc. The estimation of the significance of a binary prediction method, however, remains a cumbersome task and is usually done by repeating the calculations by Monte Carlo. The FORTRAN code provided here simplifies this problem by evaluating the significance of binary predictions for a family of ellipses which are based on confidence ellipses and cover the whole ROC space. Solution method: Using the statistics of random binary predictions for a given value of the predictor threshold ɛt, one can construct the corresponding confidence ellipses. The envelope of these corresponding confidence ellipses is estimated when

  10. Convex analysis and monotone operator theory in Hilbert spaces

    CERN Document Server

    Bauschke, Heinz H

    2017-01-01

    This reference text, now in its second edition, offers a modern unifying presentation of three basic areas of nonlinear analysis: convex analysis, monotone operator theory, and the fixed point theory of nonexpansive operators. Taking a unique comprehensive approach, the theory is developed from the ground up, with the rich connections and interactions between the areas as the central focus, and it is illustrated by a large number of examples. The Hilbert space setting of the material offers a wide range of applications while avoiding the technical difficulties of general Banach spaces. The authors have also drawn upon recent advances and modern tools to simplify the proofs of key results making the book more accessible to a broader range of scholars and users. Combining a strong emphasis on applications with exceptionally lucid writing and an abundance of exercises, this text is of great value to a large audience including pure and applied mathematicians as well as researchers in engineering, data science, ma...

  11. Explaining operational modal analysis with data from an arch bridge

    Science.gov (United States)

    Magalhães, Filipe; Cunha, Álvaro

    2011-07-01

    This tutorial paper aims to introduce the topic of operational modal analysis to non-specialists on the subject. First of all, it is stressed the relevance of this experimental technique particularly in the assessment of important civil infrastructure. Then, after a synthesis of required theoretical background, three of the most powerful algorithms for output-only modal identification are presented. The several steps of these identification procedures are illustrated with the processing of data collected on a concrete arch bridge with a span of 280 m. As the use of operational modal analysis in the context of structural health monitoring is a subject under active research, this theme is also introduced and briefly exemplified with data continuously recorded at the same bridge.

  12. Transmissibility-Based Operational Modal Analysis: Enhanced Stabilisation Diagrams

    Directory of Open Access Journals (Sweden)

    Gert De Sitter

    2012-01-01

    Full Text Available Recently it has been shown that also transmissibilities can be used to identify the modal parameters. This approach has several advantages: because of the deterministic character of the transmissibility functions, the estimated parameters are more accurate than the results obtained with the power spectra based operational modal analysis techniques. Another advantage is that the transmissibility functions do not depend on the colouring of the unknown forces. A disadvantage of the transmissibility based operational modal analysis techniques is that non-physical modes show up in the stabilisation diagrams. In this contribution it will first be shown that those non-physical modes will show up when traditional stabilisation diagrams are used. In a second step, a new approach of selecting the physical modes out of a set of estimated modes will be discussed and the new approach will be validated using data generated with an acoustical Finite Element Model. Finally, the approach will be validated using real acoustical data.

  13. Analysis on Operation Reliability of Generating Units in 2009

    Institute of Scientific and Technical Information of China (English)

    Zhou

    2010-01-01

    This paper presents the data on operation reliability indices and relevant analyses toward China's conventional power generating units in 2009. The units brought into the statistical analysis include 100-MW or above thermal generating units, 40-MW or above hydro generating units, and all nuclear generating units. The reliability indices embodied include utilization hours, times and hours of scheduled outages, times and hours of unscheduled outages, equivalent forced outage rate and equivalent availability factor.

  14. Preliminary Analysis of Helicopter Options to Support Tunisian Counterterrorism Operations

    Science.gov (United States)

    2016-04-27

    results of the current analysis and in Mouton et al., 2015, is the relative cost -effectiveness between the CH-47D and the Mi-17v5. In the previous...helicopters from Sikorsky to fulfill a number of roles in counterterrorism operations. Rising costs and delays in delivery raised the question of...whether other cost -effective options exist to meet Tunisia’s helicopter requirement. Approach Our team conducted a preliminary assessment of

  15. An operational modal analysis method in frequency and spatial domain

    Science.gov (United States)

    Wang, Tong; Zhang, Lingmi; Tamura, Yukio

    2005-12-01

    A frequency and spatial domain decomposition method (FSDD) for operational modal analysis (OMA) is presented in this paper, which is an extension of the complex mode indicator function (CMIF) method for experimental modal analysis (EMA). The theoretical background of the FSDD method is clarified. Singular value decomposition is adopted to separate the signal space from the noise space. Finally, an enhanced power spectrum density (PSD) is proposed to obtain more accurate modal parameters by curve fitting in the frequency domain. Moreover, a simulation case and an application case are used to validate this method.

  16. An operational modal analysis method in frequency and spatial domain

    Institute of Scientific and Technical Information of China (English)

    Wang Tong; Zhang Lingmi; Tamura Yukio

    2005-01-01

    A frequency and spatial domain decomposition method (FSDD) for operational modal analysis (OMA) is presented in this paper, which is an extension of the complex mode indicator function (CMIF) method for experimental modal analysis (EMA). The theoretical background of the FSDD method is clarified. Singular value decomposition is adopted to separate the signal space from the noise space. Finally, an enhanced power spectrum density (PSD) is proposed to obtain more accurate modal parameters by curve fitting in the frequency domain. Moreover, a simulation case and an application case are used to validate this method.

  17. Operational Safety Analysis of CEFR Main Feed Pump

    Institute of Scientific and Technical Information of China (English)

    DING; Tong-wei; ZHANG; Huan-qi

    2012-01-01

    <正>China Experimental Fast Reactor (CEFR) use three main feed pumps, two parallel running and one standby at full power. During CEFR operation, the pressure of deaerator is maintained at (1.16±0.01) MPa. Combined with the actual condition of the single feed pump carried out the NPSH analysis of full flow range calculation, the results are listed in Table 1. The actual measured mounting height of feed water pump is -19.2 m. The analysis results that the main feed pumps running condition cavitation does not

  18. Using Operational Analysis to Improve Access to Pulmonary Function Testing

    Directory of Open Access Journals (Sweden)

    Ada Ip

    2016-01-01

    Full Text Available Background. Timely pulmonary function testing is crucial to improving diagnosis and treatment of pulmonary diseases. Perceptions of poor access at an academic pulmonary function laboratory prompted analysis of system demand and capacity to identify factors contributing to poor access. Methods. Surveys and interviews identified stakeholder perspectives on operational processes and access challenges. Retrospective data on testing demand and resource capacity was analyzed to understand utilization of testing resources. Results. Qualitative analysis demonstrated that stakeholder groups had discrepant views on access and capacity in the laboratory. Mean daily resource utilization was 0.64 (SD 0.15, with monthly average utilization consistently less than 0.75. Reserved testing slots for subspecialty clinics were poorly utilized, leaving many testing slots unfilled. When subspecialty demand exceeded number of reserved slots, there was sufficient capacity in the pulmonary function schedule to accommodate added demand. Findings were shared with stakeholders and influenced scheduling process improvements. Conclusion. This study highlights the importance of operational data to identify causes of poor access, guide system decision-making, and determine effects of improvement initiatives in a variety of healthcare settings. Importantly, simple operational analysis can help to improve efficiency of health systems with little or no added financial investment.

  19. Using Operational Analysis to Improve Access to Pulmonary Function Testing.

    Science.gov (United States)

    Ip, Ada; Asamoah-Barnieh, Raymond; Bischak, Diane P; Davidson, Warren J; Flemons, W Ward; Pendharkar, Sachin R

    2016-01-01

    Background. Timely pulmonary function testing is crucial to improving diagnosis and treatment of pulmonary diseases. Perceptions of poor access at an academic pulmonary function laboratory prompted analysis of system demand and capacity to identify factors contributing to poor access. Methods. Surveys and interviews identified stakeholder perspectives on operational processes and access challenges. Retrospective data on testing demand and resource capacity was analyzed to understand utilization of testing resources. Results. Qualitative analysis demonstrated that stakeholder groups had discrepant views on access and capacity in the laboratory. Mean daily resource utilization was 0.64 (SD 0.15), with monthly average utilization consistently less than 0.75. Reserved testing slots for subspecialty clinics were poorly utilized, leaving many testing slots unfilled. When subspecialty demand exceeded number of reserved slots, there was sufficient capacity in the pulmonary function schedule to accommodate added demand. Findings were shared with stakeholders and influenced scheduling process improvements. Conclusion. This study highlights the importance of operational data to identify causes of poor access, guide system decision-making, and determine effects of improvement initiatives in a variety of healthcare settings. Importantly, simple operational analysis can help to improve efficiency of health systems with little or no added financial investment.

  20. Analysis on singular spaces: Lie manifolds and operator algebras

    Science.gov (United States)

    Nistor, Victor

    2016-07-01

    We discuss and develop some connections between analysis on singular spaces and operator algebras, as presented in my sequence of four lectures at the conference Noncommutative geometry and applications, Frascati, Italy, June 16-21, 2014. Therefore this paper is mostly a survey paper, but the presentation is new, and there are included some new results as well. In particular, Sections 3 and 4 provide a complete short introduction to analysis on noncompact manifolds that is geared towards a class of manifolds-called "Lie manifolds" -that often appears in practice. Our interest in Lie manifolds is due to the fact that they provide the link between analysis on singular spaces and operator algebras. The groupoids integrating Lie manifolds play an important background role in establishing this link because they provide operator algebras whose structure is often well understood. The initial motivation for the work surveyed here-work that spans over close to two decades-was to develop the index theory of stratified singular spaces. Meanwhile, several other applications have emerged as well, including applications to Partial Differential Equations and Numerical Methods. These will be mentioned only briefly, however, due to the lack of space. Instead, we shall concentrate on the applications to Index theory.

  1. Tikhonov regularization-based operational transfer path analysis

    Science.gov (United States)

    Cheng, Wei; Lu, Yingying; Zhang, Zhousuo

    2016-06-01

    To overcome ill-posed problems in operational transfer path analysis (OTPA), and improve the stability of solutions, this paper proposes a novel OTPA based on Tikhonov regularization, which considers both fitting degrees and stability of solutions. Firstly, fundamental theory of Tikhonov regularization-based OTPA is presented, and comparative studies are provided to validate the effectiveness on ill-posed problems. Secondly, transfer path analysis and source contribution evaluations for numerical cases studies on spherical radiating acoustical sources are comparatively studied. Finally, transfer path analysis and source contribution evaluations for experimental case studies on a test bed with thin shell structures are provided. This study provides more accurate transfer path analysis for mechanical systems, which can benefit for vibration reduction by structural path optimization. Furthermore, with accurate evaluation of source contributions, vibration monitoring and control by active controlling vibration sources can be effectively carried out.

  2. Numerical Analysis on Combustion Characteristic of Leaf Spring Rotary Engine

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    2015-08-01

    Full Text Available The purpose of this paper is to investigate combustion characteristics for rotary engine via numerical studies. A 3D numerical model was developed to study the influence of several operative parameters on combustion characteristics. A novel rotary engine called, “Leaf Spring Rotary Engine”, was used to illustrate the structure and principle of the engine. The aims are to (1 improve the understanding of combustion process, and (2 quantify the influence of rotational speed, excess air ratio, initial pressure and temperature on combustion characteristics. The chamber space changed with crankshaft rotation. Due to the complexity of chamber volume, an equivalent modeling method was presented to simulate the chamber space variation. The numerical simulations were performed by solving the incompressible, multiphase Unsteady Reynolds-Averaged Navier–Stokes Equations via the commercial code FLUENT using a transport equation-based combustion model; a realizable  turbulence model and finite-rate/eddy-dissipation model were used to account for the effect of local factors on the combustion characteristics.

  3. A Validated Task Analysis of the Single Pilot Operations Concept

    Science.gov (United States)

    Wolter, Cynthia A.; Gore, Brian F.

    2015-01-01

    The current day flight deck operational environment consists of a two-person Captain/First Officer crew. A concept of operations (ConOps) to reduce the commercial cockpit to a single pilot from the current two pilot crew is termed Single Pilot Operations (SPO). This concept has been under study by researchers in the Flight Deck Display Research Laboratory (FDDRL) at the National Aeronautics and Space Administration's (NASA) Ames (Johnson, Comerford, Lachter, Battiste, Feary, and Mogford, 2012) and researchers from Langley Research Centers (Schutte et al., 2007). Transitioning from a two pilot crew to a single pilot crew will undoubtedly require changes in operational procedures, crew coordination, use of automation, and in how the roles and responsibilities of the flight deck and ATC are conceptualized in order to maintain the high levels of safety expected of the US National Airspace System. These modifications will affect the roles and the subsequent tasks that are required of the various operators in the NextGen environment. The current report outlines the process taken to identify and document the tasks required by the crew according to a number of operational scenarios studied by the FDDRL between the years 2012-2014. A baseline task decomposition has been refined to represent the tasks consistent with a new set of entities, tasks, roles, and responsibilities being explored by the FDDRL as the move is made towards SPO. Information from Subject Matter Expert interviews, participation in FDDRL experimental design meetings, and study observation was used to populate and refine task sets that were developed as part of the SPO task analyses. The task analysis is based upon the proposed ConOps for the third FDDRL SPO study. This experiment possessed nine different entities operating in six scenarios using a variety of SPO-related automation and procedural activities required to guide safe and efficient aircraft operations. The task analysis presents the roles and

  4. Molten Carbonate Fuel Cell performance analysis varying cathode operating conditions for carbon capture applications

    Science.gov (United States)

    Audasso, Emilio; Barelli, Linda; Bidini, Gianni; Bosio, Barbara; Discepoli, Gabriele

    2017-04-01

    The results of a systematic experimental campaign to verify the impact of real operating conditions on the performance of a complete Molten Carbonate Fuel Cell (MCFC) are presented. In particular, the effects of ageing and composition of water, oxygen and carbon dioxide in the cathodic feeding stream are studied through the analysis of current-voltage curves and Electrochemical Impedance Spectroscopy (EIS). Based on a proposed equivalent electrical circuit model and a fitting procedure, a correlation is found among specific operating parameters and single EIS coefficients. The obtained results suggest a new performance monitoring approach to be applied to MCFC for diagnostic purpose. Particular attention is devoted to operating conditions characteristic of MCFC application as CO2 concentrators, which, by feeding the cathode with exhaust gases, is a promising route for efficient and cheap carbon capture.

  5. Lung nodule detection performance in five observers on computed tomography (CT) with adaptive iterative dose reduction using three-dimensional processing (AIDR 3D) in a Japanese multicenter study: Comparison between ultra-low-dose CT and low-dose CT by receiver-operating characteristic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nagatani, Yukihiro, E-mail: yatsushi@belle.shiga-med.ac.jp [Department of Radiology, Shiga University of Medical Science, Otsu 520-2192, Shiga (Japan); Takahashi, Masashi; Murata, Kiyoshi [Department of Radiology, Shiga University of Medical Science, Otsu 520-2192, Shiga (Japan); Ikeda, Mitsuru [Department of Radiological and Medical Laboratory Science, Nagoya University Graduate School of Medicine, Nagoya 461-8673, Aichi (Japan); Yamashiro, Tsuneo [Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara 903-0215, Okinawa (Japan); Miyara, Tetsuhiro [Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara 903-0215, Okinawa (Japan); Department of Radiology, Okinawa Prefectural Yaeyama Hospital, Ishigaki 907-0022, Okinawa (Japan); Koyama, Hisanobu [Department of Radiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Hyogo (Japan); Koyama, Mitsuhiro [Department of Radiology, Osaka Medical College, Takatsuki 569-8686, Osaka (Japan); Sato, Yukihisa [Department of Radiology, Osaka University Graduate School of Medicine, Suita 565-0871, Osaka (Japan); Department of Radiology, Osaka Medical Center of Cancer and Cardiovascular Diseases, Osaka 537-8511, Osaka (Japan); Moriya, Hiroshi [Department of Radiology, Ohara General Hospital, Fukushima 960-8611 (Japan); Noma, Satoshi [Department of Radiology, Tenri Hospital, Tenri 632-8552, Nara (Japan); Tomiyama, Noriyuki [Department of Radiology, Osaka University Graduate School of Medicine, Suita 565-0871, Osaka (Japan); Ohno, Yoshiharu [Department of Radiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Hyogo (Japan); Murayama, Sadayuki [Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara 903-0215, Okinawa (Japan)

    2015-07-15

    Highlights: • Using AIDR 3D, ULDCT showed comparable LND of solid nodules to LDCT. • Using AIDR 3D, LND of smaller GGN in ULDCT was inferior to that in LDCT. • Effective dose in ULDCT was about only twice of that in chest X-ray. • BMI values in study population were mostly in the normal range body habitus. - Abstract: Purpose: To compare lung nodule detection performance (LNDP) in computed tomography (CT) with adaptive iterative dose reduction using three dimensional processing (AIDR3D) between ultra-low dose CT (ULDCT) and low dose CT (LDCT). Materials and methods: This was part of the Area-detector Computed Tomography for the Investigation of Thoracic Diseases (ACTIve) Study, a multicenter research project being conducted in Japan. Institutional Review Board approved this study and informed consent was obtained. Eighty-three subjects (body mass index, 23.3 ± 3.2) underwent chest CT at 6 institutions using identical scanners and protocols. In a single visit, each subject was scanned using different tube currents: 240, 120 and 20 mA (3.52, 1.74 and 0.29 mSv, respectively). Axial CT images with 2-mm thickness/increment were reconstructed using AIDR3D. Standard of reference (SOR) was determined based on CT images at 240 mA by consensus reading of 2 board-certificated radiologists as to the presence of lung nodules with the longest diameter (LD) of more than 3 mm. Another 5 radiologists independently assessed and recorded presence/absence of lung nodules and their locations by continuously-distributed rating in CT images at 20 mA (ULDCT) and 120 mA (LDCT). Receiver-operating characteristic (ROC) analysis was used to evaluate LNDP of both methods in total and also in subgroups classified by LD (>4, 6 and 8 mm) and nodular characteristics (solid and ground glass nodules). Results: For SOR, 161 solid and 60 ground glass nodules were identified. No significant difference in LNDP for entire solid nodules was demonstrated between both methods, as area under ROC

  6. Analysis of Frequency Characteristics and Sensitivity of Compliant Mechanisms

    Institute of Scientific and Technical Information of China (English)

    LIU Shanzeng; DAI Jiansheng; LI Aimin; SUN Zhaopeng; FENG Shizhe; CAO Guohua

    2016-01-01

    Based on a modified pseudo-rigid-body model, the frequency characteristics and sensitivity of the large-deformation compliant mechanism are studied. Firstly, the pseudo-rigid-body model under the static and kinetic conditions is modified to enable the modified pseudo-rigid-body model to be more suitable for the dynamic analysis of the compliant mechanism. Subsequently, based on the modified pseudo-rigid-body model, the dynamic equations of the ordinary compliant four-bar mechanism are established using the analytical mechanics. Finally, in combination with the finite element analysis software ANSYS, the frequency characteristics and sensitivity of the compliant mechanism are analyzed by taking the compliant parallel-guiding mechanism and the compliant bistable mechanism as examples. From the simulation results, the dynamic characteristics of compliant mechanism are relatively sensitive to the structure size, section parameter, and characteristic parameter of material on mechanisms. The results could provide great theoretical significance and application values for the structural optimization of compliant mechanisms, the improvement of their dynamic properties and the expansion of their application range.

  7. Analysis of frequency characteristics and sensitivity of compliant mechanisms

    Science.gov (United States)

    Liu, Shanzeng; Dai, Jiansheng; Li, Aimin; Sun, Zhaopeng; Feng, Shizhe; Cao, Guohua

    2016-07-01

    Based on a modified pseudo-rigid-body model, the frequency characteristics and sensitivity of the large-deformation compliant mechanism are studied. Firstly, the pseudo-rigid-body model under the static and kinetic conditions is modified to enable the modified pseudo-rigid-body model to be more suitable for the dynamic analysis of the compliant mechanism. Subsequently, based on the modified pseudo-rigid-body model, the dynamic equations of the ordinary compliant four-bar mechanism are established using the analytical mechanics. Finally, in combination with the finite element analysis software ANSYS, the frequency characteristics and sensitivity of the compliant mechanism are analyzed by taking the compliant parallel-guiding mechanism and the compliant bistable mechanism as examples. From the simulation results, the dynamic characteristics of compliant mechanism are relatively sensitive to the structure size, section parameter, and characteristic parameter of material on mechanisms. The results could provide great theoretical significance and application values for the structural optimization of compliant mechanisms, the improvement of their dynamic properties and the expansion of their application range.

  8. Choreographer Pre-Testing Code Analysis and Operational Testing.

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, David J. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Harrison, Christopher B. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Perr, C. W. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Hurd, Steven A [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)

    2014-07-01

    Choreographer is a "moving target defense system", designed to protect against attacks aimed at IP addresses without corresponding domain name system (DNS) lookups. It coordinates actions between a DNS server and a Network Address Translation (NAT) device to regularly change which publicly available IP addresses' traffic will be routed to the protected device versus routed to a honeypot. More details about how Choreographer operates can be found in Section 2: Introducing Choreographer. Operational considerations for the successful deployment of Choreographer can be found in Section 3. The Testing & Evaluation (T&E) for Choreographer involved 3 phases: Pre-testing, Code Analysis, and Operational Testing. Pre-testing, described in Section 4, involved installing and configuring an instance of Choreographer and verifying it would operate as expected for a simple use case. Our findings were that it was simple and straightforward to prepare a system for a Choreographer installation as well as configure Choreographer to work in a representative environment. Code Analysis, described in Section 5, consisted of running a static code analyzer (HP Fortify) and conducting dynamic analysis tests using the Valgrind instrumentation framework. Choreographer performed well, such that only a few errors that might possibly be problematic in a given operating situation were identified. Operational Testing, described in Section 6, involved operating Choreographer in a representative environment created through EmulyticsTM . Depending upon the amount of server resources dedicated to Choreographer vis-á-vis the amount of client traffic handled, Choreographer had varying degrees of operational success. In an environment with a poorly resourced Choreographer server and as few as 50-100 clients, Choreographer failed to properly route traffic over half the time. Yet, with a well-resourced server, Choreographer handled over 1000 clients without missrouting. Choreographer

  9. Uncertainty Analysis of Method-Based Operating Event Groups Ranking

    Directory of Open Access Journals (Sweden)

    Zdenko Šimić

    2014-01-01

    Full Text Available Safe operation and industrial improvements are coming from the technology development and operational experience (OE feedback. A long life span for many industrial facilities makes OE very important. Proper assessment and understanding of OE remains a challenge because of organization system relations, complexity, and number of OE events acquired. One way to improve OE events understanding is to focus their investigation and analyze in detail the most important. The OE ranking method is developed to select the most important events based on the basic event parameters and the analytical hierarchy process applied at the level of event groups. This paper investigates further how uncertainty in the model affects ranking results. An analysis was performed on the set of the two databases from the 20 years of nuclear power plants in France and Germany. From all uncertainties the presented analysis selected ranking indexes as the most relevant for consideration. Here the presented analysis of uncertainty clearly shows that considering uncertainty is important for all results, especially for event groups ranked closely and next to the most important one. Together with the previously performed sensitivity analysis, uncertainty assessment provides additional insights and a better judgment of the event groups’ importance in further detailed investigation.

  10. Analysis of Vehicle Steering and Driving Bifurcation Characteristics

    Directory of Open Access Journals (Sweden)

    Xianbin Wang

    2015-01-01

    Full Text Available The typical method of vehicle steering bifurcation analysis is based on the nonlinear autonomous vehicle model deriving from the classic two degrees of freedom (2DOF linear vehicle model. This method usually neglects the driving effect on steering bifurcation characteristics. However, in the steering and driving combined conditions, the tyre under different driving conditions can provide different lateral force. The steering bifurcation mechanism without the driving effect is not able to fully reveal the vehicle steering and driving bifurcation characteristics. Aiming at the aforementioned problem, this paper analyzed the vehicle steering and driving bifurcation characteristics with the consideration of driving effect. Based on the 5DOF vehicle system dynamics model with the consideration of driving effect, the 7DOF autonomous system model was established. The vehicle steering and driving bifurcation dynamic characteristics were analyzed with different driving mode and driving torque. Taking the front-wheel-drive system as an example, the dynamic evolution process of steering and driving bifurcation was analyzed by phase space, system state variables, power spectral density, and Lyapunov index. The numerical recognition results of chaos were also provided. The research results show that the driving mode and driving torque have the obvious effect on steering and driving bifurcation characteristics.

  11. Bayesian receiver operating characteristic estimation of multiple tests for diagnosis of bovine tuberculosis in Chadian cattle.

    Directory of Open Access Journals (Sweden)

    Borna Müller

    Full Text Available BACKGROUND: Bovine tuberculosis (BTB today primarily affects developing countries. In Africa, the disease is present essentially on the whole continent; however, little accurate information on its distribution and prevalence is available. Also, attempts to evaluate diagnostic tests for BTB in naturally infected cattle are scarce and mostly complicated by the absence of knowledge of the true disease status of the tested animals. However, diagnostic test evaluation in a given setting is a prerequisite for the implementation of local surveillance schemes and control measures. METHODOLOGY/PRINCIPAL FINDINGS: We subjected a slaughterhouse population of 954 Chadian cattle to single intra-dermal comparative cervical tuberculin (SICCT testing and two recently developed fluorescence polarization assays (FPA. Using a Bayesian modeling approach we computed the receiver operating characteristic (ROC curve of each diagnostic test, the true disease prevalence in the sampled population and the disease status of all sampled animals in the absence of knowledge of the true disease status of the sampled animals. In our Chadian setting, SICCT performed better if the cut-off for positive test interpretation was lowered from >4 mm (OIE standard cut-off to >2 mm. Using this cut-off, SICCT showed a sensitivity and specificity of 66% and 89%, respectively. Both FPA tests showed sensitivities below 50% but specificities above 90%. The true disease prevalence was estimated at 8%. Altogether, 11% of the sampled animals showed gross visible tuberculous lesions. However, modeling of the BTB disease status of the sampled animals indicated that 72% of the suspected tuberculosis lesions detected during standard meat inspections were due to other pathogens than Mycobacterium bovis. CONCLUSIONS/SIGNIFICANCE: Our results have important implications for BTB diagnosis in a high incidence sub-Saharan African setting and demonstrate the practicability of our Bayesian approach for

  12. Web Content Analysis On Sustainable Campus Operation (SCO Initiatives

    Directory of Open Access Journals (Sweden)

    Razman Ruzaimah

    2017-01-01

    Full Text Available The purpose of this paper is to identify and analyse the current practices implemented in global universities for achieving sustainability throughout campus operations. This study adopted a web content analysis method where 30 international green universities’ websites have been thoroughly examined to identify common initiatives implemented to achieve sustainability through campus operations. The findings are ranked based on the implementation of these initiatives by participating universities. From the websites reviewed, as much as 31 initiatives have been identified as common initiatives frequently implemented by green universities to achieve sustainability in campus operations. It was found that the common initiatives frequently implemented by most of the universities include ‘Provide bin with clearly marked signs to increase the number of recycling items’, and ‘Generate electricity on campus by establishing power generation plants’ with 87% and 83% respectively. This paper fills the gap by presenting the investigation of sustainability initiatives from some of the major green universities internationally. It is suggested that higher education institutions, particularly Malaysian universities, initiate or manage their implementation of sustainable campus operation (SCO initiatives based on the findings of this research.

  13. A Systematic SO(10) Operator Analysis for Fermion Masses

    CERN Document Server

    Anderson, G; Dimopoulos, Savas K; Hall, L J; Starkman, G

    1994-01-01

    A new approach for deducing the theory of fermion masses at the scale of grand unification is proposed. Combining SO(10) grand unification, family symmetries and supersymmetry with a systematic operator analysis, the minimal set of fermion mass operators consistent with low energy data is determined. Exploiting the full power of SO(10) to relate up, down and charged lepton mass matrices, we obtain predictions for 7 of the mass and mixing parameters. The assumptions upon which the operator search and resulting predictions are based are stressed, together with a discussion of how the predictions are affected by a relaxation of some of the assumptions.The masses of the heaviest generation, $m_t,m_b$ and $m_\\tau$, are generated from a single renormalizable Yukawa interaction, while the lighter masses and the mixing angles are generated by non-renormalizable operators of the grand unified theory. The hierarchy of masses and mixing angles is thereby related to the ratio of grand to Planck scales, $M_G / M_P$. An ex...

  14. Working session 5: Operational aspects and risk analysis

    Energy Technology Data Exchange (ETDEWEB)

    Cizelj, L. [Jozef Stefan Institute, Ljubljana (Slovenia); Donoghue, J. [Nuclear Regulatory Commission, Washington, DC (United States)

    1997-02-01

    A general observation is that both operational aspects and risk analysis cannot be adequately discussed without information presented in other sessions. Some overlap of conclusions and recommendations is therefore to be expected. Further, it was assumed that recommendations concerning improvements in some related topics were generated by other sessions and are not repeated here. These include: (1) Knowledge on degradation mechanisms (initiation, progression, and failure). (2) Modeling of degradation (initiation, progression, and failure). (3) Capabilities of NDE methods. (4) Preventive maintenance and repair. One should note here, however, that all of these directly affect both operational and risk aspects of affected plants. A list of conclusions and recommendations is based on available presentations and discussions addressing risk and operational experience. The authors aimed at reaching as broad a consensus as possible. It should be noted here that there is no strict delineation between operational and safety aspects of degradation of steam generator tubes. This is caused by different risk perceptions in different countries/societies. The conclusions and recommendations were divided into four broad groups: human reliability; leakage monitoring; risk impact; and consequence assessment.

  15. Finite element analysis of piezoelectric underwater transducers for acoustic characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Hwan [Inha University, Incheon (Korea, Republic of); Kim, Heung Soo [Catholic University, Daegu (Korea, Republic of)

    2009-02-15

    This paper presents a simulation technique for analyzing acoustic characteristics of piezoelectric underwater transducers. A finite element method is adopted for modeling piezoelectric coupled problems including material damping and fluid-structure interaction problems by taking system matrices in complex form. For the finite element modeling of unbounded acoustic fluid, infinite wave envelope element (IWEE) is adopted to take into account the infinite domain. An in-house finite element program is developed and technical issues for implementing the program are explained. Using the simulation program, acoustic characteristics of tonpilz transducer are analyzed in terms of modal analysis, radiated pressure distribution, pressure spectrum, transmitting-voltage response and impedance analysis along with experimental comparison. The developed simulation technique can be used for designing ultrasonic transducers in the areas of nondestructive evaluation, underwater acoustics and bioengineering

  16. Operational modal analysis applied to the concert harp

    Science.gov (United States)

    Chomette, B.; Le Carrou, J.-L.

    2015-05-01

    Operational modal analysis (OMA) methods are useful to extract modal parameters of operating systems. These methods seem to be particularly interesting to investigate the modal basis of string instruments during operation to avoid certain disadvantages due to conventional methods. However, the excitation in the case of string instruments is not optimal for OMA due to the presence of damped harmonic components and low noise in the disturbance signal. Therefore, the present study investigates the least-square complex exponential (LSCE) and the modified least-square complex exponential methods in the case of a string instrument to identify modal parameters of the instrument when it is played. The efficiency of the approach is experimentally demonstrated on a concert harp excited by some of its strings and the two methods are compared to a conventional modal analysis. The results show that OMA allows us to identify modes particularly present in the instrument's response with a good estimation especially if they are close to the excitation frequency with the modified LSCE method.

  17. Characteristic analysis of low consumption power ISO solenoid valve

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Y. S.; Ju, M. J.; Oh, Y. C. [FAMCO, Gyeongju (Korea, Republic of); Kim, D. S. [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)

    2008-07-01

    In this study, A special quality analysis and experiment for low power consumption type pneumatic ISO Solenoid valve was performed. And flow characteristics of the ISO Solenoid valve by stroke change was numerically investigated. As a result, it is shown that magnetic force(2.4N) is exerted enough to move poppet with 0.3mm stroke with 0.01 seconds of response time, and that there is no magnetic force emitted by yoke.

  18. Radiation Analysis and Characteristics of Conformal Reflectarray Antennas

    Directory of Open Access Journals (Sweden)

    Payam Nayeri

    2012-01-01

    Full Text Available This paper investigates the feasibility of designing reflectarray antennas on conformal surfaces. A generalized analysis approach is presented that can be applied to compute the radiation performance of conformal reflectarray antennas. Using this approach, radiation characteristics of conformal reflectarray antennas on singly curved platforms are studied and the performances of these designs are compared with planar designs. It is demonstrated that a conformal reflectarray antenna can be a suitable choice for applications requiring high-gain antennas on curved platforms.

  19. Operational modal analysis modeling, Bayesian inference, uncertainty laws

    CERN Document Server

    Au, Siu-Kui

    2017-01-01

    This book presents operational modal analysis (OMA), employing a coherent and comprehensive Bayesian framework for modal identification and covering stochastic modeling, theoretical formulations, computational algorithms, and practical applications. Mathematical similarities and philosophical differences between Bayesian and classical statistical approaches to system identification are discussed, allowing their mathematical tools to be shared and their results correctly interpreted. Many chapters can be used as lecture notes for the general topic they cover beyond the OMA context. After an introductory chapter (1), Chapters 2–7 present the general theory of stochastic modeling and analysis of ambient vibrations. Readers are first introduced to the spectral analysis of deterministic time series (2) and structural dynamics (3), which do not require the use of probability concepts. The concepts and techniques in these chapters are subsequently extended to a probabilistic context in Chapter 4 (on stochastic pro...

  20. Operational Auditing in, Hospitality Businesses via Data Envelopment Analysis

    Directory of Open Access Journals (Sweden)

    Süleyman Uyar

    2014-12-01

    Full Text Available In today's world, as in almost all sectors, there is intense competition in the tourism sector. Activity levels of accommodation establishments in the tourism sector have a very important place because of competitive market conditions. When it comes to efficiency measurem ent, control activities come to mind. Data Envelopment Analysis (DEA can be used in operational auditing as a tool for performance measurement The purpose of this study is to make the operational auditing activities of accommodation establishments in Alanya with the DEA. In this study, data for the year 2013 of 37 accommodation establishments were evaluated. As input variables, number of rooms, number of beds, the annual average number of employees, annual energy costs and annual food and beverage expenses were used. As output variables; customer satisfaction, the annual number of overnight stays, occupancy rates and room revenues are used. The obtained results show that the accommodation establishments of five are active.

  1. Analysis on second operation after laser in situ keratomileusis

    Directory of Open Access Journals (Sweden)

    Wen-Xuan Pei

    2015-07-01

    Full Text Available AIM: To observe clinical effects between the laser in situ keratomileusis(LASIKsurgery and the laser subepithelial keratomileusis(LASEKsurgery as the second operation after an unsuccessful LASIK surgery. METHODS:Forty-nine patients(98 eyeswith refractive regression after LASIK operation received the second surgery. All patients were divided into two groups: group A and B. Group A(48 eyes of 24 patientsreceived LASIK surgery and group B(50 eyes of 25 patientsreceived LASEK surgery. Inspect the main parameters included visual acuity, refraction, corneal curvature, and the total value of high-aberration after 1wk, 1mo and 1a, t-test of groups was used as statistical analysis method.RESULTS: There was statistically significant(PP>0.05. There developed one case of epithelium in growth after LASIK surgery, and one case of haze Ⅱ after LASEK surgery. CONCLUSION: Both LASIK and LASEK surgery can obtain satisfactory therapeutic results after an unsuccessful LASIK surgery.

  2. Analysis of stress effects on the cognitive operating work

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Cheol Jung; Park, Jae Hee; Lee, Nahm Sik; Yu, Young Kwan [Korea Research Institute of Standards and Science, Taejon (Korea, Republic of)

    1994-07-01

    This study is carried out to develop the performance evaluation model which explains the relationship between PSFs(performance shaping factors) and performance. The model can improve the safety efficiency of the nuclear power plants by removing the wrong PSFs. The work scope and contents of the project have the following items, such as, survey of the performance evaluation/prediction models, selecting the PSFs and performance measures, task analysis on the EOP(emergency operating procedures) for LOCA(loss of coolant accident) and modeling the relationships between PSFs and performance measures, and knowledge representation using the IF...THEN... rules. The results, knowledge base, can be used to develop the performance evaluation model for nuclear power plant operators. 46 refs.

  3. Receiver-operating characteristic curves for somatic cell scores and California mastitis test in Valle del Be lice dairy sheep

    NARCIS (Netherlands)

    Riggio, V.; Pesce, L.L.; Morreale, S.; Portolano, B.

    2013-01-01

    Using receiver-operating characteristic (ROC) curve methodology this study was designed to assess the diagnostic effectiveness of somatic cell count (SCC) and the California mastitis test (CMT) in Valle del Belice sheep, and to propose and evaluate threshold values for those tests that would optimal

  4. Receiver-operating characteristic curves for somatic cell scores and California mastitis test in Valle del Be lice dairy sheep

    NARCIS (Netherlands)

    Riggio, V.; Pesce, L.L.; Morreale, S.; Portolano, B.

    2013-01-01

    Using receiver-operating characteristic (ROC) curve methodology this study was designed to assess the diagnostic effectiveness of somatic cell count (SCC) and the California mastitis test (CMT) in Valle del Belice sheep, and to propose and evaluate threshold values for those tests that would

  5. The precision--recall curve overcame the optimism of the receiver operating characteristic curve in rare diseases

    DEFF Research Database (Denmark)

    Ozenne, Brice; Subtil, Fabien; Maucort-Boulch, Delphine

    2015-01-01

    OBJECTIVES: Compare the area under the receiver operating characteristic curve (AUC) vs. the area under the precision-recall curve (AUPRC) in summarizing the performance of a diagnostic biomarker according to the disease prevalence. STUDY DESIGN AND SETTING: A simulation study was performed...

  6. [Hardware-software system for monitoring parameters and characteristics of X-ray computer tomographs under operation conditions].

    Science.gov (United States)

    Blinov, N N; Zelikman, M I; Kruchinin, S A

    2007-01-01

    The results of testing of hardware and software for monitoring parameters (mean number of CT units, noise, field uniformity, high-contrast spatial resolution, layer width, dose) and characteristics (modulation transfer function) of X-ray computer tomographs are presented. The developed hardware and software are used to monitor the stability of X-ray computer tomograph parameters under operation conditions.

  7. Relationship between construction characteristics and carbon emissions from urban household operational energy usage

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Hong; Wang, Kai; Zhao, Xiaofeng; Chen, Feng; Li, Xuanqi; Pan, Lingyang [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, Fujian 361021 (China)

    2011-01-15

    Carbon emitted from urban metabolism constitutes a substantial proportion of the anthropogenic greenhouse gas emission, which is at least partially responsible for the recent global warming. Part of the urban carbon emission comes from residential energy consumption. Given the ongoing rapid urbanization and strict emission-reduction requirement, understanding the urban home energy usage carbon emission (UHEUCE) is of great importance to optimize the sustainability of social and economic developments in China. For this reason, a survey has been conducted to exam the condition of home energy usage in Xiamen Island, SE China. This study was based on 340 valid responses and a general linear model for univariate method. The analysis showed (1) among the residential building characteristics, window thermal insulation has the greatest effect on UHEUCE. (2) Construction age and wall thermal insulation could also influence UHEUCE in areas where summer is hot and winter is warm. The better heat prohibiting effect of external wall and window, as well as the newer construction, the more UHEUCE can be generated. The survey provided helpful first-hand data for design and planning on urban energy saving, emission reduction, and for relevant scientific researches. (author)

  8. PERFORMANCE AND EMISSION CHARACTERISTICS OF A CI ENGINE OPERATED ON VEGETABLE OILS AS ALTERNATIVE FUELS

    Directory of Open Access Journals (Sweden)

    K. Rajagopal

    2011-12-01

    Full Text Available An experimental analysis was done using a four-stroke, single cylinder, constant speed, water-cooled diesel engine, which was interfaced with Engine software. Performance and emission characteristics were evaluated for three non-edible vegetable oils, i.e. thumba, jojoba, neem oil, as well as jojoba methyl ester, to study the effect of injection pressure at 205, 220, 240 and 260 bar with a variation in injection timing at 23°bTDC and 28°bTDC. The performance of jojoba methyl ester improved with an increase in injection pressure. A maximum brake thermal efficiency of 29.72% was obtained with lower emissions compared to the other vegetable oils; this might be explained by low viscosity and better combustion. Further investigations were carried out with a new lubricant, SAE 5W-30, which improved the performance of the CI engine by 1.59%. All of the abovementioned investigations were fruitful and these results are expected to lead to substantial contributions in the development of a viable vegetable oil engine.

  9. Characteristics and performance of membrane electrode assemblies with operating conditions in polymer electrolyte membrane fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong-Hun [School of Advanced Materials Engineering, Kookmin University, 861-1 Jeongneung-dong, Seongbuk-gu, Seoul 136-702 (Korea, Republic of); Yoo, Sung Jong [Fuel Cell Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Park, In-Su; Jeon, Tae-Yeol; Cho, Yoon-Hwan; Lim, Ju Wan [World Class University (WCU) program of Chemical Convergence for Energy and Environment, School of Chemical and Biological Engineering, College of Engineering, Seoul National University (SNU), Seoul (Korea, Republic of); Kwon, Oh Joong [Department of Energy and Chemical Engineering, University of Incheon, 12-1 Songdo-dong, Yeonsu-gu, Incheon 406-772 (Korea, Republic of); Yoon, Won-Sub [School of Advanced Materials Engineering, Kookmin University, 861-1 Jeongneung-dong, Seongbuk-gu, Seoul 136-702 (Korea, Republic of); Sung, Yung-Eun, E-mail: ysung@snu.ac.k [World Class University (WCU) program of Chemical Convergence for Energy and Environment, School of Chemical and Biological Engineering, College of Engineering, Seoul National University (SNU), Seoul (Korea, Republic of)

    2010-12-30

    The degradation behavior of a membrane-electrode assembly (MEA) was investigated in accelerated degradation tests under constant voltage (0.8 V and 0.7 V) and load cycling (from open circuit voltage to 0.35 V) conditions. Changes in the structural and electrochemical characteristics of MEA after the durability tests give information as to the degradation mechanism of MEAs. The results of cyclic voltammogram and postmortem analysis by X-ray diffraction and high resolution-transmission electron microscopy indicate that the cathode catalyst layers of the MEAs showed no extreme degradation under constant voltage mode, whereas MEAs under repetition of load cycling mode showed very severe degradation after 280 h. However, the single cell performance of the MEA under repetition of load cycling mode was higher than under constant voltage mode. In addition, although the Pt band in the membrane of the MEA under repetition of load cycling mode was observed by field emission scanning electron microscopy, it did not affect the ohmic resistance.

  10. James Webb Space Telescope Deployment Brushless DC Motor Characteristics Analysis

    Science.gov (United States)

    Tran, Ahn N.

    2016-01-01

    A DC motor's performance is usually characterized by a series of tests, which are conducted by pass/fail criteria. In most cases, these tests are adequate to address the performance characteristics under environmental and loading effects with some uncertainties and decent power/torque margins. However, if the motor performance requirement is very stringent, a better understanding of the motor characteristics is required. The purpose of this paper is to establish a standard way to extract the torque components of the brushless motor and gear box characteristics of a high gear ratio geared motor from the composite geared motor testing and motor parameter measurement. These torque components include motor magnetic detent torque, Coulomb torque, viscous torque, windage torque, and gear tooth sliding torque. The Aerospace Corp bearing torque model and MPB torque models are used to predict the Coulomb torque of the motor rotor bearings and to model the viscous components. Gear tooth sliding friction torque is derived from the dynamo geared motor test data. With these torque data, the geared motor mechanical efficiency can be estimated and provide the overall performance of the geared motor versus several motor operating parameters such as speed, temperature, applied current, and transmitted power.

  11. Parametric analysis of loop heat pipe operation: a literature review

    Energy Technology Data Exchange (ETDEWEB)

    Launay, Stephane; Sartre, Valerie; Bonjour, Jocelyn [Centre de Thermique UMR 5008 CNRS-INSA-Universite Lyon 1, Institut National des Sciences Appliquees, Bat. Sadi Carnot, 9 rue de la Physique, 69 621 Villeurbanne cedex (France)

    2007-07-15

    Loop heat pipes (LHPs) are heat transfer devices whose operating principle is based on the evaporation/condensation of a working fluid, and which use the capillary pumping forces to ensure the fluid circulation. Their major advantages as compared to heat pipes are an ability to operate against gravity and a greater maximum heat transport capability. In this paper, a literature review is carried out in order to investigate how various parameters affect the LHP operational characteristics. This review is based on the most recent published experimental and theoretical studies. After a reminder of the LHP operating principle and thermodynamic cycle, their operating limits are described. The LHP thermal resistance and maximum heat transfer capability are affected by the choice of the working fluid, the fill charge ratio, the porous wick geometry and thermal properties, the sink and ambient temperature levels, the design of the evaporator and compensation chamber, the elevation and tilt, the presence of non-condensable gases, the pressure drops of the fluid along the loop. The overall objective for this paper is to point the state-of-the-art for the related technology for future design and applications, where the constraints related to the LHPs are detailed and discussed. (author) [French] Les boucles diphasiques a pompage capillaire sont des systemes dont le principe de fonctionnement est base sur l'evaporation/condensation d'un fluide et qui utilisent les forces de capillarite pour faire circuler le fluide dans la boucle. En comparaison des caloducs, les principaux avantages des boucles diphasiques a pompage capillaire sont une aptitude a vaincre les forces de gravite, lorsque le systeme est en position defavorable, et une puissance maximale transferable superieure. La presente etude bibliographique, basee sur les travaux experimentaux et theoriques les plus recents, a pour but est de comprendre comment differents parametres influencent le comportement de la

  12. Dynamic Characteristic Analysis and Experiment for Integral Impeller Based on Cyclic Symmetry Analysis Method

    Institute of Scientific and Technical Information of China (English)

    WU Qiong; ZHANG Yidu; ZHANG Hongwei

    2012-01-01

    A cyclic symmetry analysis method is proposed for analyzing the dynamic characteristic problems of thin walled integral impeller.Reliability and feasibility of the present method are investigated by means of simulation and experiment.The fundamental cyclic symmetry equations and the solutions of these equations are derived for the cyclic symmetry structure.The computational efficiency analysis between whole and part is performed.Comparison of results obtained by the finite element analysis (FEA)and experiment shows that the local dynamic characteristic of integral impeller has consistency with the single cyclic symmetry blade.When the integral impeller is constrained and the thin walled blade becomes a concerned object in analysis,the dynamic characteristic of integral impeller can be replaced by the cyclic symmetry blade approximately.Hence,a cyclic symmetry analysis method is effectively used to improve efficiency and obtain more information of parameters for dynamic characteristic of integral impellers.

  13. Drive Control Scheme of Electric Power Assisted Wheelchair Based on Neural Network Learning of Human Wheelchair Operation Characteristics

    Science.gov (United States)

    Tanohata, Naoki; Seki, Hirokazu

    This paper describes a novel drive control scheme of electric power assisted wheelchairs based on neural network learning of human wheelchair operation characteristics. “Electric power assisted wheelchair” which enhances the drive force of the operator by employing electric motors is expected to be widely used as a mobility support system for elderly and disabled people. However, some handicapped people with paralysis of the muscles of one side of the body cannot maneuver the wheelchair as desired because of the difference in the right and left input force. Therefore, this study proposes a neural network learning system of such human wheelchair operation characteristics and a drive control scheme with variable distribution and assistance ratios. Some driving experiments will be performed to confirm the effectiveness of the proposed control system.

  14. Thermodynamic Analysis of Dual-Mode Scramjet Engine Operation and Performance

    Science.gov (United States)

    Riggins, David; Tacket, Regan; Taylor, Trent; Auslender, Aaron

    2006-01-01

    Recent analytical advances in understanding the performance continuum (the thermodynamic spectrum) for air-breathing engines based on fundamental second-law considerations have clarified scramjet and ramjet operation, performance, and characteristics. Second-law based analysis is extended specifically in this work to clarify and describe the performance characteristics for dual-mode scramjet operation in the mid-speed range of flight Mach 4 to 7. This is done by a fundamental investigation of the complex but predictable interplay between heat release and irreversibilities in such an engine; results demonstrate the flow and performance character of the dual mode regime and of dual mode transition behavior. Both analytical and computational (multi-dimensional CFD) studies of sample dual-mode flow-fields are performed in order to demonstrate the second-law capability and performance and operability issues. The impact of the dual-mode regime is found to be characterized by decreasing overall irreversibility with increasing heat release, within the operability limits of the system.

  15. SPECIAL ANALYSIS OF OPERATIONAL STORMWATER RUNOFF COVERS OVER SLIT TRENCHES

    Energy Technology Data Exchange (ETDEWEB)

    Collard, L; Luther Hamm, L

    2008-12-18

    Solid Waste Management (SWM) commissioned this Special Analysis (SA) to determine the effects of placing operational stormwater runoff covers (referred to as covers in the remainder of this document) over slit trench (ST) disposal units ST1 through ST7 (the center set of slit trenches). Previously the United States Department of Energy (DOE) entered into an agreement with the United States Environmental Protection Agency (EPA) and the South Carolina Department of Health and Environmental Control (SCDHEC) to place covers over Slit Trenches 1 and 2 to be able to continue disposing Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) solid waste (see USDOE 2008). Because the covers changed the operating conditions, DOE Order 435.1 (DOE 1999) required that an SA be performed to assess the impact. This Special Analysis has been prepared to determine the effects of placing covers over slit trenches at about years 5, 10 and 15 of the 30-year operational period. Because some slit trenches have already been operational for about 15 years, results from analyzing covers at 5 years and 10 years provide trend analysis information only. This SA also examined alternatives of covering Slit Trenches 1 and 2 with one cover and Slit Trenches 3 and 4 with a second cover versus covering them all with a single cover. Based on modeling results, minimal differences exist between covering Slit Trench groups 1-2 and 3-4 with two covers or one large cover. This SA demonstrates that placement of covers over slit trenches will slow the subsequent release and transport of radionuclides in the vadose zone in the early time periods (from time of placement until about 100 years). Release and transport of some radionuclides in the vadose zone beyond 100 years were somewhat higher than for the case without covers. The sums-of-fractions (SOFs) were examined for the current waste inventory in ST1 and ST2 and for estimated inventories at closure for ST3 through ST7. In all

  16. Operational modal analysis of road-rail bridge

    OpenAIRE

    Cardoso M.; Sampaio R. A. C.; de Souza R. M.; Silva E.

    2015-01-01

    In this paper, we describe an Operational Modal Analysis (OMA) of the Bridge over the Tocantins River, a composite road-rail bridge located in the city of Marabá, state of Pará, northern Brazil. The bridge is part of the Carajás Railway, which is used by VALE Company to transport iron ore from “Serra dos Carajás”, the largest mineral reserve of the planet. The bridge has a length of 2310m, being the second longest road-rail bridge in Brazil. The study focused on the bridge central span (with ...

  17. Evaluation of Damping Using Frequency Domain Operational Modal Analysis Techniques

    DEFF Research Database (Denmark)

    Bajric, Anela; Georgakis, Christos T.; Brincker, Rune

    2015-01-01

    Operational Modal Analysis (OMA) techniques provide in most cases reasonably accurate estimates of structural frequencies and mode shapes. In contrast though, they are known to often produce uncertain structural damping estimates, which is mainly due to inherent random and/or bias errors...... domain techniques, the Frequency Domain Decomposition (FDD) and the Frequency Domain Polyreference (FDPR). The response of a two degree-of-freedom (2DOF) system is numerically established with specified modal parameters subjected to white noise loading. The system identification is evaluated with well...

  18. Eliminating the Influence of Harmonic Components in Operational Modal Analysis

    DEFF Research Database (Denmark)

    Jacobsen, Niels-Jørgen; Andersen, Palle; Brincker, Rune

    2007-01-01

    on the well-known Enhanced Frequency Domain Decomposition (EFDD) technique for eliminating these harmonic components in the modal parameter extraction process. For assessing the quality of the method, various experiments were carried out where the results were compared with those obtained with pure stochastic......Operational modal analysis is used for determining the modal parameters of structures for which the input forces cannot be measured. However, the algorithms used assume that the input forces are stochastic in nature. While this is often the case for civil engineering structures, mechanical...

  19. Quantitative risk analysis in two pipelines operated by TRANSPETRO

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Claudio B. [PETROBRAS Transporte S/A (TRANSPETRO), Rio de Janeiro, RJ (Brazil); Pinho, Edson [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil); Bittencourt, Euclides [Centro Universitario FIB, Salvador , BA (Brazil)

    2009-07-01

    Transportation risk analysis techniques were used to study two pipelines operated by TRANSPETRO. The Pipeline A is for the simultaneous transportation of diesel, gasoline and LPG and comprises three parts, all of them crossing rural areas. The Pipeline B is for oil transportation and one of its ends is located in an area of a high density population. Both pipelines had their risk studied using the PHAST RISK{sup R} software and the individual risk measures, the only considered measures for license purposes for this type of studies, presented level far below the maximum tolerable levels considered. (author)

  20. Determination of operating characteristic, retesting, and testing amount probabilities associated with testing for the presence of Salmonella in foods.

    Science.gov (United States)

    McClure, Foster D; Lee, Jung K

    2011-01-01

    The relatively small perceived probability associated with retesting a food for the presence of Salmonella at low levels is often considered as one of the reasons that a confirmatory or check-analysis tends to disagree in practice with the results of an original test. Given a retesting process where a retest is only performed to confirm an original positive Salmonella test, the probability that both the original and retest will test positive for Salmonella has been traditionally determined by some as the product of the probabilities of a positive Salmonella test for the original and retest samples. When examining the probabilities associated with the retesting process, we found that our results disagreed with those based on intuitions apparently held by others concerning how these probabilities should be calculated. For Salmonella testing, operating characteristic values were computed to demonstrate the protections afforded by the Salmonella sampling plans presented in the U.S. Food and Drug Administration's Bacteriological Analytical Manual and to obtain the probability of a positive Salmonella test. The geometric distribution was examined for possible utility in determining the probabilities associated with testing amounts, i.e., the number of Salmonella tests needed to obtain a positive test.

  1. Main morphological characteristics of the vascular pedicle of latissimus dorsi muscle and their relevance in operative treatment

    Directory of Open Access Journals (Sweden)

    Ilić Marko

    2010-01-01

    Full Text Available Introduction. Considering operative treatment of various pathological conditions and traumatic injuries of extremities latissimus dorsi flap presents the most frequently used flap in reconstructive surgery. Objective. The aim of this paper was to analyze anatomical characteristics of the vascular pedicle of the latissimus dorsi muscle followed by morphometric analyzes of vascular elements. Methods. This paper was carried out in cooperation with the Institute of Anatomy of the School of Medicine, University of Belgrade. The study was based on 40 cadaver dissections followed by anatomical and morphometric analyzes. The first analysis included the determination of thoracodorsal artery (TDA origin and its lateral and terminal branches, and the second one the observation of artery path. Furthermore the same features were analyzed on the thoracodorsal vein. During morphometric analyzes artery and vein length and diameter were recorded. Results. Our results showed that TDA always contains one lateral branch, while three other lateral branches were inconstant. In most cases TDA terminated in two branches, upper and lower, with average distance of 3.4 cm from the muscle. The mean recorded pedicle length was 9.9 cm. The average inner diameter of TDA was 1.85 mm. In further analyses the average observed thoracodorsal vein length was 10.5 cm with mean diameter of 2.93 mm. The result showed that vein origin was usually represented with two branches. Conclusion. The thoracodorsal artery is a blood vessel of considerable length and diameter which represents a great advantage in reconstructive flap surgery.

  2. Operator`s guide for VAXGAP, a gamma-ray spectrum analysis package

    Energy Technology Data Exchange (ETDEWEB)

    Killian, E.W.; Femec, D.A.

    1992-08-01

    This report describes the gamma-ray analysis program VAXGAP, which has continually evolved at the Idaho National Engineering Laboratory over a period of several years. It is an integrated suite of computer programs for performing analyses of pulse-height spectra from high-resolution gamma-ray spectrometers and assorted support functions. VAXGAP programs operate on Digital Equipment Corporation (DEC) VAX computers running the VMS operating system, and were written in VAX FORTRAN and DEC Digital Command Language (DCL). These programs make use of DEC GKS and ReGIS for graphical output on standard terminals and printers, and DEC windows for graphics on workstations and terminals that support the X Window System protocol. This report addresses the use of VAXGAP for data acquisition and control, energy scale calibration, and real-time analyses of background and sample pulse-height spectra. Also addressed are the creation and use efficiency tables and isotope libraries, manipulation of spectrum files and their contents, and graphical display of on-going acquisitions, saved spectra, and mathematical fits to spectral peaks.

  3. Analysis of viral clearance unit operations for monoclonal antibodies.

    Science.gov (United States)

    Miesegaes, George; Lute, Scott; Brorson, Kurt

    2010-06-01

    Demonstration of viral clearance is a critical step in assuring the safety of biotechnology products. We generated a viral clearance database that contains product information, unit operation process parameters, and viral clearance data from monoclonal antibody and antibody-related regulatory submissions to FDA. Here we present a broad overview of the database and resulting analyses. We report that the diversity of model viruses tested expands as products transition to late-phase. We also present averages and ranges of viral clearance results by Protein A and ion exchange chromatography steps, low pH chemical inactivation, and virus filtration, focusing on retro- and parvoviruses. For most unit operations, an average log reduction value (LRV, a measure of clearance power) for retrovirus of >4 log(10) were measured. Cases where clearance data fell outside of the anticipated range (i.e., outliers) were rationally explained. Lastly, a historical analysis did not find evidence of any improvement trend in viral clearance over time. The data collectively suggest that many unit operations in general can reliably clear viruses.

  4. Statistical Scalability Analysis of Communication Operations in Distributed Applications

    Energy Technology Data Exchange (ETDEWEB)

    Vetter, J S; McCracken, M O

    2001-02-27

    Current trends in high performance computing suggest that users will soon have widespread access to clusters of multiprocessors with hundreds, if not thousands, of processors. This unprecedented degree of parallelism will undoubtedly expose scalability limitations in existing applications, where scalability is the ability of a parallel algorithm on a parallel architecture to effectively utilize an increasing number of processors. Users will need precise and automated techniques for detecting the cause of limited scalability. This paper addresses this dilemma. First, we argue that users face numerous challenges in understanding application scalability: managing substantial amounts of experiment data, extracting useful trends from this data, and reconciling performance information with their application's design. Second, we propose a solution to automate this data analysis problem by applying fundamental statistical techniques to scalability experiment data. Finally, we evaluate our operational prototype on several applications, and show that statistical techniques offer an effective strategy for assessing application scalability. In particular, we find that non-parametric correlation of the number of tasks to the ratio of the time for individual communication operations to overall communication time provides a reliable measure for identifying communication operations that scale poorly.

  5. Youth hypertension cerebral hemorrhage in basal ganglia surgery operation analysis

    Institute of Scientific and Technical Information of China (English)

    Qi-Hua Wang; Da-Shuang Lu; Jie Cui; Bo-Lin Qiao; Jing-Chun Wang

    2016-01-01

    Objective:Discuss surgical treatment of youth hypertension cerebral hemorrhage in basal ganglia.Methods:Retrospective analysis from January 2012 to April 2015 were adopted to bone flap craniotomy decompression for removal of hematoma and drainage drilling two kinds of surgical treatment of 46 cases of young patients with hypertension cerebral hemorrhage in basal ganglia.Results:Surgical operation, 28 patients postoperative review head CT, no further hemorrhage cases, residual hematoma volume 2-6 mL. Drilling drainage in the treatment of 18 patients, 1 case was bleeding again given surgical operation to remove the hematoma and the rest of the 17 cases without bleeding again, after 3 d, 17 cases of patients of postoperative hematoma drainage thoroughly. After 6 months, 46 cases of patients with postoperative review, GOS score light disability 9 cases, moderate disability 33 cases, 4 cases were severely disabled, curative effect is satisfied.Conclusions:Two kinds of operative methods each have advantages and disadvantages, young patients with hypertension cerebral hemorrhage in basal ganglia should according to patients' disease progression after speed, on admission patient's state of consciousness and head CT measured on admission hematoma volume, respectively.

  6. Reactivation characteristics of stored aerobic granular sludge using different operational strategies.

    Science.gov (United States)

    Yuan, Xiangjuan; Gao, Dawen; Liang, Hong

    2012-06-01

    Aerobic granules after 6 months storage were employed in identical sequencing batch reactors (SBRs) using synthetic wastewater to investigate the impacts of different operational strategies on granules' reactivation process. The SBRs were operated under three operational strategies for reactivation of (a) different organic loading rate (OLR); (b) different ammonia concentration; and (c) different shear force (a superficial upflow air velocity). The results indicated that granules after long-term storage could be successfully recovered after 7 days of operation, and the excellent granule reactivation performance was closely related to the operational strategies, since inappropriate operational strategies could cause the outgrowth of filamentous bacteria and granule disintegration. Based on comprehensive comparison of reactivation performance under different operational strategies, the optimal operation strategy for granule reactivation was suggested at OLR of 0.8 kg COD/m(3)/day, ammonia concentration of 15-20 mg/L, and a superficial upflow air velocity of 2.6 cm/s. After 7 days operation under the optimal strategy, the dark brown granules (12 months storage) restored their bioactivities to previous state, in terms of COD removal efficiency (97.44%) and specific oxygen uptake rate (40.63 mg O(2)/g SS h(-1)). The results shed light on the future practical application of stored aerobic granules as bioseed for reactor fast start-up.

  7. Hazardous-waste analysis plan for LLNL operations

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, R.S.

    1982-02-12

    The Lawrence Livermore National Laboratory is involved in many facets of research ranging from nuclear weapons research to advanced Biomedical studies. Approximately 80% of all programs at LLNL generate hazardous waste in one form or another. Aside from producing waste from industrial type operations (oils, solvents, bottom sludges, etc.) many unique and toxic wastes are generated such as phosgene, dioxin (TCDD), radioactive wastes and high explosives. One key to any successful waste management program must address the following: proper identification of the waste, safe handling procedures and proper storage containers and areas. This section of the Waste Management Plan will address methodologies used for the Analysis of Hazardous Waste. In addition to the wastes defined in 40 CFR 261, LLNL and Site 300 also generate radioactive waste not specifically covered by RCRA. However, for completeness, the Waste Analysis Plan will address all hazardous waste.

  8. Towards an integral computer environment supporting system operations analysis and conceptual design

    Science.gov (United States)

    Barro, E.; Delbufalo, A.; Rossi, F.

    1994-01-01

    VITROCISET has in house developed a prototype tool named System Dynamic Analysis Environment (SDAE) to support system engineering activities in the initial definition phase of a complex space system. The SDAE goal is to provide powerful means for the definition, analysis, and trade-off of operations and design concepts for the space and ground elements involved in a mission. For this purpose SDAE implements a dedicated modeling methodology based on the integration of different modern (static and dynamic) analysis and simulation techniques. The resulting 'system model' is capable of representing all the operational, functional, and behavioral aspects of the system elements which are part of a mission. The execution of customized model simulations enables: the validation of selected concepts with respect to mission requirements; the in-depth investigation of mission specific operational and/or architectural aspects; and the early assessment of performances required by the system elements to cope with mission constraints and objectives. Due to its characteristics, SDAE is particularly tailored for nonconventional or highly complex systems, which require a great analysis effort in their early definition stages. SDAE runs under PC-Windows and is currently used by VITROCISET system engineering group. This paper describes the SDAE main features, showing some tool output examples.

  9. Kinematic Characteristics Analysis of 3-PRS Parallel Manipulator

    Institute of Scientific and Technical Information of China (English)

    ZHANG Fan; YANG Jiang-guo; LI Bei-zhi

    2008-01-01

    The 3-PRS parallel mechanisms, whose kinematic chain is connected by prismatic joint P, revolute joint R and spherical joint S, have two rotational and one translational DOF. But the DOF of 3-PRS parallel mechanism cannot be explained by the Grubler-Kutzbach method or Herve method. To illuminate the special kinematic characteristics of 3-PRS parallel mechanism, a novel analytical approach is proposed in this paper. All the feasible instantaneous motions of 3-PRS mechanism are studied by using this method. The analysis of kinematic characteristics of 3-PRS mechanism help to understand the mechanism and estimate the motion capacity of mechanism. Finally, it is also helpful to optimize the topology of the mechanism and the trajectory for desired performance.

  10. COMPARATIVE ANALYSIS OF PERFORMANCE CHARACTERISTICS OF JET VORTEX TYPE SUPERCHAGES

    Directory of Open Access Journals (Sweden)

    A. Rogovyi

    2016-06-01

    Full Text Available On the basis of mathematical modeling there was carried out a comparative analysis of characteristics of jet vortex type superchargers. Dependences of the energy performance of vortex ejector on the geometry parameters and the largest values in terms of efficiency as well as the coefficient of ejection are analyzed. There were built combined characteristics of vortex chamber pumps and vortex ejectors. Vortex chamber pump has advantage pressure in an exit channel over the vortex ejector, consequently there is a more effective power transmission from a working medium, besides the withdrawal of pumping medium in a tangential channel allows to avoid energy losses owing to rotation of a stream in an exit channel.

  11. Contribution to the theoretical and experimental analysis of camshaft engine operation

    Science.gov (United States)

    Sutter, Guy

    1991-02-01

    A study concerning an alternative engine whose linkage is replaced by a piston-pad-cam assembly is presented. The transmission systems are described in order to study the volume generated by the piston movement at output shaft rotation. The cam power transmission study is presented as follows: global description; piston dynamics; cam shaft synchronization; profile analysis. A mathematical model of the real time operation of the engine related to a cam shaft engine prototype study shows the advantage of choosing a cam profile, particularly during combustion. A method for determining the principle characteristics of the main components of a cam shaft engine, whose desired performances are known, is defined.

  12. Statistical and Spectral Analysis of Wind Characteristics Relevant to Wind Energy Assessment Using Tower Measurements in Complex Terrain

    OpenAIRE

    Radian Belu; Darko Koracin

    2013-01-01

    The main objective of the study was to investigate spatial and temporal characteristics of the wind speed and direction in complex terrain that are relevant to wind energy assessment and development, as well as to wind energy system operation, management, and grid integration. Wind data from five tall meteorological towers located in Western Nevada, USA, operated from August 2003 to March 2008, used in the analysis. The multiannual average wind speeds did not show significant increased trend ...

  13. Investigating the effect of characteristic x-rays in cadmium zinc telluride detectors under breast computerized tomography operating conditions.

    Science.gov (United States)

    Glick, Stephen J; Didier, Clay

    2013-10-14

    A number of research groups have been investigating the use of dedicated breast computerized tomography (CT). Preliminary results have been encouraging, suggesting an improved visualization of masses on breast CT as compared to conventional mammography. Nonetheless, there are many challenges to overcome before breast CT can become a routine clinical reality. One potential improvement over current breast CT prototypes would be the use of photon counting detectors with cadmium zinc telluride (CZT) (or CdTe) semiconductor material. These detectors can operate at room temperature and provide high detection efficiency and the capability of multi-energy imaging; however, one factor in particular that limits image quality is the emission of characteristic x-rays. In this study, the degradative effects of characteristic x-rays are examined when using a CZT detector under breast CT operating conditions. Monte Carlo simulation software was used to evaluate the effect of characteristic x-rays and the detector element size on spatial and spectral resolution for a CZT detector used under breast CT operating conditions. In particular, lower kVp spectra and thinner CZT thicknesses were studied than that typically used with CZT based conventional CT detectors. In addition, the effect of characteristic x-rays on the accuracy of material decomposition in spectral CT imaging was explored. It was observed that when imaging with 50-60 kVp spectra, the x-ray transmission through CZT was very low for all detector thicknesses studied (0.5-3.0 mm), thus retaining dose efficiency. As expected, characteristic x-ray escape from the detector element of x-ray interaction increased with decreasing detector element size, approaching a 50% escape fraction for a 100 μm size detector element. The detector point spread function was observed to have only minor degradation with detector element size greater than 200 μm and lower kV settings. Characteristic x-rays produced increasing distortion

  14. Model validity and frequency band selection in operational modal analysis

    Science.gov (United States)

    Au, Siu-Kui

    2016-12-01

    Experimental modal analysis aims at identifying the modal properties (e.g., natural frequencies, damping ratios, mode shapes) of a structure using vibration measurements. Two basic questions are encountered when operating in the frequency domain: Is there a mode near a particular frequency? If so, how much spectral data near the frequency can be included for modal identification without incurring significant modeling error? For data with high signal-to-noise (s/n) ratios these questions can be addressed using empirical tools such as singular value spectrum. Otherwise they are generally open and can be challenging, e.g., for modes with low s/n ratios or close modes. In this work these questions are addressed using a Bayesian approach. The focus is on operational modal analysis, i.e., with 'output-only' ambient data, where identification uncertainty and modeling error can be significant and their control is most demanding. The approach leads to 'evidence ratios' quantifying the relative plausibility of competing sets of modeling assumptions. The latter involves modeling the 'what-if-not' situation, which is non-trivial but is resolved by systematic consideration of alternative models and using maximum entropy principle. Synthetic and field data are considered to investigate the behavior of evidence ratios and how they should be interpreted in practical applications.

  15. Energetic analysis of fruit juice processing operations in Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Waheed, M.A.; Imeokparia, O.E. [Ladoke Akintola University of Technology, Ogbomoso, Oyo State (Nigeria). Mechanical Engineering Department; Jekayinfa, S.O.; Ojediran, J.O. [Ladoke Akintola University of Technology, Ogbomoso, Oyo State (Nigeria). Agricultural Engineering Department

    2008-01-15

    Energy and exergy studies were conducted in an orange juice manufacturing industry in Nigeria to determine the energy consumption pattern and methods of energy optimization in the company. An adaptation of the process analysis method of energy accounting was used to evaluate the energy requirement for each of the eight defined unit operations. The types of energy used in the manufacturing of orange juice were electrical, steam and manual with the respective proportions of 18.51%, 80.91% and 0.58% of the total energy. It was estimated that an average energy intensity of 1.12 MJ/kg was required for the manufacturing of orange juice. The most energy intensive operation was identified as the pasteurizer followed by packaging unit with energy intensities of 0.932 and 0.119 MJ/kg, respectively. The exergy analysis revealed that the pasteurizer was responsible for most of the inefficiency (over 90%) followed by packaging (6.60%). It was suggested that the capacity of the pasteurizer be increased to reduce the level of inefficiency of the plant. The suggestion has been limited to equipment modification rather than process alteration, which constitutes additional investment cost and may not be economical from an energy savings perspective. (author)

  16. Chemical Analysis of Wastewater from Unconventional Drilling Operations

    Directory of Open Access Journals (Sweden)

    Jonathan B. Thacker

    2015-04-01

    Full Text Available Trillions of liters of wastewater from oil and gas extraction are generated annually in the US. The contribution from unconventional drilling operations (UDO, such as hydraulic fracturing, to this volume will likely continue to increase in the foreseeable future. The chemical content of wastewater from UDO varies with region, operator, and elapsed time after production begins. Detailed chemical analyses may be used to determine its content, select appropriate treatment options, and identify its source in cases of environmental contamination. In this study, one wastewater sample each from direct effluent, a disposal well, and a waste pit, all in West Texas, were analyzed by gas chromatography-mass spectrometry, inductively coupled plasma-optical emission spectroscopy, high performance liquid chromatography-high resolution mass spectrometry, high performance ion chromatography, total organic carbon/total nitrogen analysis, and pH and conductivity analysis. Several compounds known to compose hydraulic fracturing fluid were detected among two of the wastewater samples including 2-butoxyethanol, alkyl amines, and cocamide diethanolamines, toluene, and o-xylene. Due both to its quantity and quality, proper management of wastewater from UDO will be essential.

  17. Methodological frontier in operational analysis for roundabouts: a review

    Directory of Open Access Journals (Sweden)

    Orazio Giuffre'

    2016-11-01

    Full Text Available Several studies and researches have shown that modern roundabouts are safe and effective as engineering countermeasures for traffic calming, and they are now widely used worldwide. The increasing use of roundabouts and, more recently, turbo and flower roundabouts, has induced a great variety of experiences in the field of intersection design, traffic safety and capacity modelling. As for unsignalized intersections which represent the starting point to extend knowledge about the operational analysis to roundabouts, the general situation in capacity estimation is still characterized by the discussion between gap acceptance models and empirical regression models. However, capacity modelling must contain both the analytical construction and then solution of the model, and the implementation of driver behavior. Thus, issues on a realistic modelling of driver behavior by the parameters that are included into the models are always of interest for practioners and analysts in transportation and road infrastructure engineering. Based on these considerations, this paper presents a literature review about the key methodological issues in the operational analysis of modern roundabouts. Focus is made on the aspects associated with the gap acceptance behavior, the derivation of the analytical-based models and the calculation of parameters included into the capacity equations, as well as steady state and non-steady state conditions and uncertainty in entry capacity estimation. At last, insights on future developments of the research in this field of investigation will be also outlined.

  18. Mission Analysis, Operations, and Navigation Toolkit Environment (Monte) Version 040

    Science.gov (United States)

    Sunseri, Richard F.; Wu, Hsi-Cheng; Evans, Scott E.; Evans, James R.; Drain, Theodore R.; Guevara, Michelle M.

    2012-01-01

    Monte is a software set designed for use in mission design and spacecraft navigation operations. The system can process measurement data, design optimal trajectories and maneuvers, and do orbit determination, all in one application. For the first time, a single software set can be used for mission design and navigation operations. This eliminates problems due to different models and fidelities used in legacy mission design and navigation software. The unique features of Monte 040 include a blowdown thruster model for GRAIL (Gravity Recovery and Interior Laboratory) with associated pressure models, as well as an updated, optimalsearch capability (COSMIC) that facilitated mission design for ARTEMIS. Existing legacy software lacked the capabilities necessary for these two missions. There is also a mean orbital element propagator and an osculating to mean element converter that allows long-term orbital stability analysis for the first time in compiled code. The optimized trajectory search tool COSMIC allows users to place constraints and controls on their searches without any restrictions. Constraints may be user-defined and depend on trajectory information either forward or backwards in time. In addition, a long-term orbit stability analysis tool (morbiter) existed previously as a set of scripts on top of Monte. Monte is becoming the primary tool for navigation operations, a core competency at JPL. The mission design capabilities in Monte are becoming mature enough for use in project proposals as well as post-phase A mission design. Monte has three distinct advantages over existing software. First, it is being developed in a modern paradigm: object- oriented C++ and Python. Second, the software has been developed as a toolkit, which allows users to customize their own applications and allows the development team to implement requirements quickly, efficiently, and with minimal bugs. Finally, the software is managed in accordance with the CMMI (Capability Maturity Model

  19. Analysis of forest backscattering characteristics based on polarization coherence tomography

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    It is difficult to make an inventory of vertical profiles of forest structure parameters in field measurements.However,analysis and understanding of forest backscattering characteristics contribute to estimation and detection of forest vertical structure because of the close relationships between backscattering characteristics and structure parameters.The vertical structure function in the complex interferometric coherence definition,which represents the vertical variation of microwave scattering with the penetration depth at a point in the 2-D radar image and can be used to analyze the forest backscattering characteristics,can be reconstructed from polarization coherence tomography(PCT).Based on PCT,the paper analyzes the forest backscattering characteristics and explores the inherent relationship between the result of PCT and the forest structure parameters from numerical simulation of Random Volume over Ground model(RVoG),Polarimetric SAR interferometry(PolInSAR)simulation of forest scene and PolInSAR data at L-band of the test site Traunstein.Firstly,the effects of the extinction coefficient and surface-to-volume scattering ratio in RVoG model on vertical backscattering characteristics are analyzed by means of numerical simulation.Secondly,by applying PCT to L-band POLInSAR simulations of forest scene,different variations of vertical backscattering due to different extinction coefficients and the ratios of surface-to-volume scattering resulting from different polarizations,forest types and densities are displayed and analyzed.Then a concept of relative average backscattering intensity is presented,and the factors which affect its vertical distribution are also discussed.Preliminary results show that there is high sensitivity of the vertical distribution of forest relative average backscattering intensity to the polarization,forest type and density.Finally,based on repeat pass DLR E-SAR L-band airborne POLInSAR data,the capability of PCT technology for detection

  20. Applications of human error analysis to aviation and space operations

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, W.R.

    1998-07-01

    For the past several years at the Idaho National Engineering and Environmental Laboratory (INEEL) we have been working to apply methods of human error analysis to the design of complex systems. We have focused on adapting human reliability analysis (HRA) methods that were developed for Probabilistic Safety Assessment (PSA) for application to system design. We are developing methods so that human errors can be systematically identified during system design, the potential consequences of each error can be assessed, and potential corrective actions (e.g. changes to system design or procedures) can be identified. These applications lead to different requirements when compared with HR.As performed as part of a PSA. For example, because the analysis will begin early during the design stage, the methods must be usable when only partial design information is available. In addition, the ability to perform numerous ''what if'' analyses to identify and compare multiple design alternatives is essential. Finally, since the goals of such human error analyses focus on proactive design changes rather than the estimate of failure probabilities for PRA, there is more emphasis on qualitative evaluations of error relationships and causal factors than on quantitative estimates of error frequency. The primary vehicle we have used to develop and apply these methods has been a series of projects sponsored by the National Aeronautics and Space Administration (NASA) to apply human error analysis to aviation operations. The first NASA-sponsored project had the goal to evaluate human errors caused by advanced cockpit automation. Our next aviation project focused on the development of methods and tools to apply human error analysis to the design of commercial aircraft. This project was performed by a consortium comprised of INEEL, NASA, and Boeing Commercial Airplane Group. The focus of the project was aircraft design and procedures that could lead to human errors during

  1. 刃天青还原分析法在用接收器特性法评估雄猪精液中的诊断意义%Determination of the diagnostic value of the resazurin reduction assay for evaluating boar semen by receiver operating characteristic analysis

    Institute of Scientific and Technical Information of China (English)

    Petra Zrim(s)ek; Marjan Kosec; Janez Kunc; Janko Mrkun

    2006-01-01

    Aim: To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality.Methods: The accuracy of the spectrophotometric application of the resazurin reduction assay was assessed using receiver operating characteristic (ROC) analysis. Results: Areas under ROC curves (AUC) for motile sperm concentration and sperm index (SI) (sperm concentration multiplied by the square root of percentage sperm motility multiplied by the percentage normal sperm morphology) were 0.922. The best discrimination between poor and good semen samples according to the SI was achieved at a cut-off point of A610 = 0.209, where high sensitivity (94.1%) and specificity (91.7%) were calculated. The assay was less accurate when motile sperm concentration was used as the criterion value, yielding sensitivity of 88.2% and specificity of 87.5%, respectively. Likelihood ratios (LR) indicate that absorbances lower than 0.209 were at least 11.3 times as likely to be found in good semen samples than those in poor according to the SI, whereas in the case of motile sperm concentration, the LR was calculated to be 7.06. Conclusion:These results show that the resazurin reduction assay combined with spectrophotometry is an accurate method of assessing the quality of boar semen.%目的:确定精子代谢状态可以作为一个有用的精液质量分析工具.方法:用接收器特性法(ROC)评估刃天青还原法联合分光光度计法的精确度.结果:活动精子密度和精子指数(SI)(精子密度×精子活力百分比的平方根×形态正常精子百分比)的ROC曲线下面积为0.992.参考SI值,采集到的精液样本的质量高低区分点的吸光度为0.209(610nm波长),该点的敏感性和特异性值分别为94.1%和91.7%.如果以活动精子密度为标准值,这种分析方法的精确度就会降低,敏感性和特异性值分别为88.2%和87.5%.似然比(LR)表明在质量良好的精液样本中测得的吸光度低于0.209,至少相当

  2. Tuk-tuk, ‘new kid on the block’ in Johannesburg: Operational and user travel characteristics, competition and impacts

    Directory of Open Access Journals (Sweden)

    Tatenda C. Mbara

    2016-01-01

    Full Text Available The three-wheeler tuk-tuk, popular in Asian cities is now a common feature in many cities worldwide, across all five continents. Their growth has been attributed to their distinctive flexibility, stylistic simplicity and modest operational costs. In Johannesburg, the tuk-tuk represents a relatively new mode of public transport which stemmed from suggestions made by the local area residents association and other stakeholders to revamp the neighbourhood. The objective of the paper is to determine the operational and user travel characteristics of tuk-tuks as well as assessing their impacts. In Johannesburg, where competition from private transport operators can result in serious confrontation, the paper ascertains whether tuktuks pose a threat to other operators. Data was collected through telephonic interviews and electronic questionnaires. The results reveal that the tuk-tuk has filled a public transport gap by providing a much needed ‘first mile’/‘last mile’ service to community members.

  3. Analysis of experimental characteristics of multistage steam-jet electors of steam turbines

    Science.gov (United States)

    Aronson, K. E.; Ryabchikov, A. Yu.; Brodov, Yu. M.; Brezgin, D. V.; Zhelonkin, N. V.; Murmanskii, I. B.

    2017-02-01

    A series of questions for specification of physical gas dynamics model in flow range of steam-jet unit and ejector computation methodology, as well as functioning peculiarities of intercoolers, was formulated based on analysis of experimental characteristics of multistage team-jet steam turbines. It was established that coefficient defining position of critical cross-section of injected flow depends on characteristics of the "sound tube" zone. Speed of injected flow within this tube may exceed that of sound, and pressure jumps in work-steam decrease at the same time. Characteristics of the "sound tube" define optimal axial sizes of the ejector. According to measurement results, the part of steam condensing in the first-stage coolant constitutes 70-80% of steam amount supplied into coolant and is almost independent of air content in steam. Coolant efficiency depends on steam pressure defined by operation of steam-jet unit of ejector of the next stage after coolant of steam-jet stage, temperature, and condensing water flow. As a rule, steam entering content of steam-air mixture supplied to coolant is overheated with respect to saturation temperature of steam in the mixture. This should be taken into account during coolant computation. Long-term operation causes changes in roughness of walls of the ejector's mixing chamber. The influence of change of wall roughness on ejector characteristic is similar to the influence of reverse pressure of the steam-jet stage. Until some roughness value, injection coefficient of the ejector stage operating in superlimiting regime hardly changed. After reaching critical roughness, the ejector switches to prelimiting operating regime.

  4. Genetic diversity analysis of fruit characteristics of hawthorn germplasm.

    Science.gov (United States)

    Su, K; Guo, Y S; Wang, G; Zhao, Y H; Dong, W X

    2015-12-07

    One hundred and six accessions of hawthorn intraspecific resources, from the National Germplasm Repository at Shenyang, were subjected to genetic diversity and principal component analysis based on evaluation data of 15 fruit traits. Results showed that the genetic diversity of hawthorn fruit traits varied. Among the 15 traits, the fruit shape variable coefficient had the most obvious evaluation, followed by fruit surface state, dot color, taste, weight of single fruit, sepal posture, peduncle form, and metula traits. These are the primary traits by which hawthorn could be classified in the future. The principal component demonstrated that these traits are the most influential factors of hawthorn fruit characteristics.

  5. Kinematic and Dynamic Characteristics Analysis of Bennett’ s Linkage

    Institute of Scientific and Technical Information of China (English)

    Jianfeng Li

    2015-01-01

    Bennett’ s linkage is a spatial fourlink linkage, and has an extensive application prospect in the deployable linkages.Its kinematic and dynamic characteristics analysis has a great significance in its synthesis and application. According to the geometrical conditions of Bennett ’ s linkage, the motion equations are established,and the expressions of angular displacement, angular velocity and angular acceleration of the followers and the displacement, velocity and acceleration of mass center of link are shown. Based on Lagrange’ s equation, the multi⁃rigid⁃body dynamic model of Bennett’ s linkage is established. In order to solve the reaction forces and moments of joint, screw theory and reciprocal screw method are combined to establish the computing method.The number of equations and unknown reaction forces and moments of joint are equal through adding link deformation equations. The influence of the included angle of adjacent axes on Bennett ’ s linkage ’ s kinematic characteristics, the dynamic characteristics and the reaction forces and moments of joint are analyzed. Results show that the included angle of adjacent axes has a great effect on velocity, acceleration, the reaction forces and moments of Bennett’ s linkage. The change of reaction forces and moments of joint are apparent near the singularity configuration.

  6. Bearing capacity analysis using the method of characteristics

    Institute of Scientific and Technical Information of China (English)

    Jian-Ping Sun; Zhi-Ye Zhao; Yi-Pik Cheng

    2013-01-01

    Using the method of characteristics,the bearing capacity for a strip footing is analyzed.The method of characteristics leads to an exact true limit load when the calculations of the three terms in the bearing capacity formula are consistent with one collapse mechanism and the soil satisfies the associated flow rule.At the same time,the method of characteristics avoids the assumption of arbitrary slip surfaces,and produces zones within which equilibrium and plastic yield are simultaneously satisfied for given boundary stresses.The exact solution without superposition approximation can still be expressed by Terzaghi's equation of bearing capacity,in which the bearing capacity factor Nyλ is dependent on the dimensionless parameterλand the friction angle φ.The influence of groundwater on the bearing capacity of the shallow strip footing is considered,which indicates that when the groundwater effect is taken into account,the error induced by the superposition approximation can be reduced as compared with dry soil condition.The results are presented in the form of charts which give the modified value (yλcw/Nyλc) of bearing capacity factor.Finally,an approximated analytical expression,which provides results in close agreement with those obtained by numerical analysis in this paper,has been suggested for practical application purposes.

  7. An Outlook on Agricultural Modernization Path with Chinese Characteristics from Scale Agricultural Operation

    Institute of Scientific and Technical Information of China (English)

    Wanjiang; WANG

    2015-01-01

    First of all,this paper discusses the scale agricultural operation of China from the aspects of practical exploration and rational thinking. Later,it puts forward the concept of further promoting scale agricultural operation according to the present conditions of China,which includes encouraging large household pattern and scale breeding,developing various forms of socialized agricultural services,promoting agriculture industrialization,accelerating regional distribution of advantageous agricultural products and promoting the progress in agricultural science and technology comprehensively.

  8. Analysis of the Pump-turbine S Characteristics Using the Detached Eddy Simulation Method

    Institute of Scientific and Technical Information of China (English)

    SUN Hui; XIAO Ruofu; WANG Fujun; XIAO Yexiang; LIU Weichao

    2015-01-01

    Current research on pump-turbine units is focused on the unstable operation at off-design conditions, with the characteristic curves in generating mode being S-shaped. Unlike in the traditional water turbines, pump-turbine operation along the S-shaped curve can lead to difficulties during load rejection with unusual increases in the water pressure, which leads to machine vibrations. This paper describes both model tests and numerical simulations. A reduced scale model of a low specific speed pump-turbine was used for the performance tests, with comparisons to computational fluid dynamics(CFD) results. Predictions using the detached eddy simulation(DES) turbulence model, which is a combined Reynolds averaged Naviers-Stokes(RANS) and large eddy simulation(LES) model, are compared with the two-equation turbulence mode results. The external characteristics as well as the internal flow are for various guide vane openings to understand the unsteady flow along the so called S characteristics of a pump-turbine. Comparison of the experimental data with the CFD results for various conditions and times shows that DES model gives better agreement with experimental data than the two-equation turbulence model. For low flow conditions, the centrifugal forces and the large incident angle create large vortices between the guide vanes and the runner inlet in the runner passage, which is the main factor leading to the S-shaped characteristics. The turbulence model used here gives more accurate simulations of the internal flow characteristics of the pump-turbine and a more detailed force analysis which shows the mechanisms controlling of the S characteristics.

  9. Characteristic analysis and prevention on premature convergence in genetic algorithms

    Institute of Scientific and Technical Information of China (English)

    徐宗本; 高勇

    1997-01-01

    The identification and characteristics of premature convergence in genetic algorithms (GAs) are investigated Through a detailed quantitative analysis on the search capability and the degree of population diversity, the cause of premature convergence in GAs is recognized, and attributed to the maturation effect of the GAs: The minimum schema deduced from current population, which is the largest search space of a GA, converges to a homogeneous population in probability 1 ( so the search capability of the GA decreases and premature convergence occurs). It is shown that, as quantitative features of the maturation effect, the degree of population diversity converges to zero with probability 1, and the tendency for premature convergence is inversely proportional to the population size and directly proportional to the variance of the fitness ratio of zero allele at any gene position of the current population. Based on the theoretical analysis, several strategies for preventing premature convergence are suggest

  10. Finite element analysis for acoustic characteristics of a magnetostrictive transducer

    Science.gov (United States)

    Kim, Jaehwan; Jung, Eunmi

    2005-12-01

    This paper presents a finite element analysis for a magnetostrictive transducer by taking into account the nonlinear behavior of the magnetostrictive material and fluid interaction. A finite element formulation is derived for the coupling of magnetostrictive and elastic materials based upon a separated magnetic and displacement field calculation and a curve fitting technique of material properties. The fluid and structure coupled problem is taken into account based upon pressure and velocity potential fields formulation. Infinite wave envelope elements are introduced at an artificial boundary to deal with the infinite fluid domain. A finite element code for the analysis of a magnetostrictive transducer is developed. A magnetostrictive tonpilz transducer is taken as an example and verification for the developed program is made by comparing with a commercial code. The acoustic characteristics of the magnetostrictive tonpilz transducer are calculated in terms of radiation pattern and transmitted current response.

  11. Composite Operator Method Analysis of the Underdoped Cuprates Puzzle

    Directory of Open Access Journals (Sweden)

    Adolfo Avella

    2014-01-01

    Full Text Available The microscopical analysis of the unconventional and puzzling physics of the underdoped cuprates, as carried out lately by means of the composite operator method (COM applied to the 2D Hubbard model, is reviewed and systematized. The 2D Hubbard model has been adopted as it has been considered the minimal model capable of describing the most peculiar features of cuprates held responsible for their anomalous behavior. COM is designed to endorse, since its foundation, the systematic emergence in any SCS of new elementary excitations described by composite operators obeying noncanonical algebras. In this case (underdoped cuprates—2D Hubbard model, the residual interactions—beyond a 2-pole approximation—between the new elementary electronic excitations, dictated by the strong local Coulomb repulsion and well described by the two Hubbard composite operators, have been treated within the noncrossing approximation. Given this recipe and exploiting the few unknowns to enforce the Pauli principle content in the solution, it is possible to qualitatively describe some of the anomalous features of high-Tc cuprate superconductors such as large versus small Fermi surface dichotomy, Fermi surface deconstruction (appearance of Fermi arcs, nodal versus antinodal physics, pseudogap(s, and kinks in the electronic dispersion. The resulting scenario envisages a smooth crossover between an ordinary weakly interacting metal sustaining weak, short-range antiferromagnetic correlations in the overdoped regime to an unconventional poor metal characterized by very strong, long-but-finite-range antiferromagnetic correlations leading to momentum-selective non-Fermi liquid features as well as to the opening of a pseudogap and to the striking differences between the nodal and the antinodal dynamics in the underdoped regime.

  12. ANALYSIS OF OPERATING CHARACTERISTICS IN KSTAR PF COILS SYSTEM UNDER SINGLE AND CONTINUOUS PLASMA DISCHARGING CONDICTIONS%在单一和连续等离子体放电条件下KSTAR PF线圈的运行特性分析

    Institute of Scientific and Technical Information of China (English)

    王秋良; Keeman Kim; Wohoo Chung; 冯遵安

    2003-01-01

    The operating characteristics in the poloidal field (PF) coils system of KSTAR ( Korean Superconducting Tokamak Advanced Research ) for given operating scenarios are analyzed by SAITOKPF. In order to control the plasma shape in KSTAR to realize the thermal nuclear fusion reaction, the operating currents in PF coils are controlled with high various rate with respect to time. The induced current in the support structure and cryostat generates high eddy losses. It also produces the large hysteresis, eddy and coupling losses in superconducting coils. The supercritical helium with high velocity through the cable-in-conduit-conductor (CICC) removes the heat load to keep the temperature of superconducting cable lower than its current sharing temperature. The maximum temperature rise in PF1 is studied under the various inlet pressures for helium (He) while the output pressure of He is kept constant of 3Mpa. The single and continuous operating scenario for KSTAR are studied to decide the maximum temperature rise and total AC losses.%我们使用分析程序SAITOKSCPF研究了KSTAR PF 超导线圈的运行特性.为了控制KSTAR超导托卡马克的运行等离子的外形以便实现受控热核聚变反应,在超导PF线圈内通过高变化率的运行电流.由于电磁感应,在超导线圈、支持结构和低温容器内产生感应电流和损耗.超临界氦流过CICC导体内部保持超导体运行在4.2K的温度.分析表明最大的温度在PF1线圈内部.在这篇论文中,我们对于单一和连续条件下等离子体放电对超导体运行的影响进行了研究.

  13. Risk analysis for autonomous underwater vehicle operations in extreme environments.

    Science.gov (United States)

    Brito, Mario Paulo; Griffiths, Gwyn; Challenor, Peter

    2010-12-01

    Autonomous underwater vehicles (AUVs) are used increasingly to explore hazardous marine environments. Risk assessment for such complex systems is based on subjective judgment and expert knowledge as much as on hard statistics. Here, we describe the use of a risk management process tailored to AUV operations, the implementation of which requires the elicitation of expert judgment. We conducted a formal judgment elicitation process where eight world experts in AUV design and operation were asked to assign a probability of AUV loss given the emergence of each fault or incident from the vehicle's life history of 63 faults and incidents. After discussing methods of aggregation and analysis, we show how the aggregated risk estimates obtained from the expert judgments were used to create a risk model. To estimate AUV survival with mission distance, we adopted a statistical survival function based on the nonparametric Kaplan-Meier estimator. We present theoretical formulations for the estimator, its variance, and confidence limits. We also present a numerical example where the approach is applied to estimate the probability that the Autosub3 AUV would survive a set of missions under Pine Island Glacier, Antarctica in January-March 2009.

  14. Special Operations Forces (SOF) technical analysis and evaluation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1987-08-31

    In response to Task Order 001, Los Alamos National Laboratory Contract 9-L5H-1508P-1, Betac Corporation is pleased to provide ten quick-response, short-term analytical papers in support of Low Intensity Conflict (LIC) and Special Operations (SO). The papers are study methodologies which provide background, baseline, concepts, approaches, and recommendations in the mission areas identified in the Statement of Work. Although the Statement of Work specifies only nine papers, a tenth paper has been included addressing Command Relationships, since this subject affects all other topics and is of critical importance to USCINCSOC in establishing the United States Special Operations Command (USSOCOM). Each paper addresses the feasibility of further effort in each area of interest. The ten papers address: (1) mission support systems; (2) research, development, and acquisition; (3) headquarters equipment; (4) C3I architecture; (5) intelligence dissemination; (6) intelligence collection management; (7) intelligence support to SOF targeting; (8) joint mission area analysis (JMAA); (9) joint SOF master plan; and (10) command relationships.

  15. Steady State Analysis of Small Molten Salt Reactor : Effect of Fuel Salt Flow on Reactor Characteristics

    OpenAIRE

    Yamamoto, Takahisa; MITACHI, Koshi; Suzuki, Takashi

    2005-01-01

    The Molten Salt Reactor (MSR) is a thermal neutron reactor with graphite moderation and operates on the thorium-uranium fuel cycle. The feature of the MSR is that fuel salt flows inside the reactor during the nuclear fission reaction. In the previous study, the authors developed numerical model with which to simulate the effects of fuel salt flow on the reactor characteristics. In this study, we apply the model to the steady-state analysis of a small MSR system and estimate the effects of fue...

  16. Interval arithmetic operations for uncertainty analysis with correlated interval variables

    Institute of Scientific and Technical Information of China (English)

    Chao Jiang; Chun-Ming Fu; Bing-Yu Ni; Xu Han

    2016-01-01

    A new interval arithmetic method is proposed to solve interval functions with correlated intervals through which the overestimation problem existing in interval analy-sis could be significantly alleviated. The correlation between interval parameters is defined by the multidimensional par-allelepiped model which is convenient to describe the correlative and independent interval variables in a unified framework. The original interval variables with correlation are transformed into the standard space without correlation, and then the relationship between the original variables and the standard interval variables is obtained. The expressions of four basic interval arithmetic operations, namely addi-tion, subtraction, multiplication, and division, are given in the standard space. Finally, several numerical examples and a two-step bar are used to demonstrate the effectiveness of the proposed method.

  17. Analysis of information systems for hydropower operations: Executive summary

    Science.gov (United States)

    Sohn, R. L.; Becker, L.; Estes, J.; Simonett, D.; Yeh, W.

    1976-01-01

    An analysis was performed of the operations of hydropower systems, with emphasis on water resource management, to determine how aerospace derived information system technologies can effectively increase energy output. Better utilization of water resources was sought through improved reservoir inflow forecasting based on use of hydrometeorologic information systems with new or improved sensors, satellite data relay systems, and use of advanced scheduling techniques for water release. Specific mechanisms for increased energy output were determined, principally the use of more timely and accurate short term (0-7 days) inflow information to reduce spillage caused by unanticipated dynamic high inflow events. The hydrometeorologic models used in predicting inflows were examined in detail to determine the sensitivity of inflow prediction accuracy to the many variables employed in the models, and the results were used to establish information system requirements. Sensor and data handling system capabilities were reviewed and compared to the requirements, and an improved information system concept was outlined.

  18. The Analysis of Operations Management Strategies of IKEA

    Institute of Scientific and Technical Information of China (English)

    吴梦柯

    2012-01-01

    The Analysis of Operations Management Strategies oflKEA IKEA, as a multinational corporation, is a world famous home furniture company whose vision is "To provide better life for everYone". IKEA was founded in 1943 by Ingvar Karaprad, a young entrepreneur from Elmtaryd, Sweden. Initially Kamprad sold a wide range of products such as pencils, nylon stockings, wallets and watches via mail order. In 1948 Ikea started offering furniture for sale, and three years later the first edition of the Ikea catalogue was released. The first IKEA store opened in 1958 in Almhult, Sweden. From i958, the company expanded fast, opening its first store abroad in 1963. Since then, IKEA has expanded to 38 countries and 301 stores:

  19. Application analysis of empirical mode decomposition and phase space reconstruction in dam time-varying characteristic

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In view of some courses of the time-varying characteristics processing in the analysis of dam deformation,the paper proposes a new method to analyze the dam time-varying characteristic based on the empirical mode decomposition and phase space reconstruction theory.First of all,to reduce the influences on the traditional statistical model from human factors and assure the analysis accuracy,response variables of the time-varying characteristic are obtained by the way of the empirical mode decomposition;and then,a phase plane of those variables is reconstructed to investigate their processing rules.These methods have already been applied to an actual project and the results showed that data interpretation with the assists of empirical mode decomposition and phase space reconstruction is effective in analyzing the perturbations of response variables,explicit in reflecting the entire development process,and valid for obtaining the evolution rules of the time-varying characteristic.This methodology is a powerful technical support for people to further master the rules of dam operation.

  20. Operating Characteristic Analysis of Permanent Magnet Synchronous Generator with Chopper Circuit Responded to the Power System Short Circuit Fault%含chopper电路的直驱风机响应电网短路的运行特性分析

    Institute of Scientific and Technical Information of China (English)

    刘勇; 麻广林; 宁波; 魏鑫

    2016-01-01

    In order to analyze the operating characteristics of permanent magnet synchronous generator ( PMSG) impacted by the power system short circuit fault, this paper researches maximum wind energy tracking control strat⁃egy of the wind turbine the machine side decoupling control strategy of active and reactive power of the AC⁃DC⁃AC converter and voltage orientation strategy of the gird side by mathematical model. For meeting the wind turbine low voltage ride through ( LVRT) requirement, DC capacitor chooper protection circuit is used. When short⁃circuit fault occurs discharge resistance in chooper circuit can unload the energy, which could maintain the DC capacitor voltage stabilitily. At the same time the reference current limiter can also limit the impaction on the grid side con⁃verter by power system short circuit fault. The PMSG simulation model is constructed in emtp⁃rv platform, and its operating characteristics is simulated in the condition of power system three⁃phase short⁃circuit fault, causing the grid voltage drops below 0. 2. The simulation results verify the control strategy correctly and DC capacitor chooper protection circuit effectively. The results provide the basis for the operating characteristic of the PMSG grid⁃con⁃necting to the power system and the influence of power system short⁃circuit fault on the PMSG.%为了分析电网短路时的直驱风电机组运行特性,从数学模型入手,研究了风轮机最大风能追踪控制策略,以及交直交变频器机侧的有功无功解耦控制策略和网侧的电压定向控制策略。为了满足风电机组的低电压穿越要求,采用了直流电容chooper保护电路。电网短路故障时, chooper回路中的卸能电阻能很大程度地消耗短路冲击带来的能量,从而维持直流电容电压稳定。同时参考电流限值器也限制了短路冲击对网侧变频器的影响。在empt⁃rv中搭建了直驱风机模型,分析了电网三相

  1. Ship operation and failure mode analysis using a maneuver simulator

    Science.gov (United States)

    Cabrerizo-Morales, Miguel Angel; Molina, Rafael; de los Santos, Francisco; Camarero, Alberto

    2013-04-01

    In a ship or floating structure operation the agents that contribute to the systems behaviour are not only those derived from fluid-structure interaction, but also the ones linked to mooring-control line set-up evolution and human interaction. Therefore, the analysis of such systems is affected by boundary conditions that change during a complete operation. Frequently, monitoring techniques in laboratory (model) and field (prototype) are based in different instrumental techniques adding difficulty to data comparison and, in some cases, inducing precision and repeatability errors. For this reason, the main aim of this study is to develop the methods and tools to achieve a deep knowledge of those floating systems and obtain capabilities to optimize their operationally thresholds. This abstract presents a methodology and an instrumental system applicable both in field and laboratory: SRECMOCOS Project (Small scale REal-time Caisson MOnitoring and COntrol System). SRECMOCOS compiles three modules. For the monitoring and control of the structure it has been developed a synchronized open and modular microcontroller-based electronic system that comprises sensors, to monitor agents and reactions, and actuators to perform pertinent actions after processing the sensors' data. A secondary objective has been to design and implement a global scaled simulator (1:22), at the 3D basin of The Harbour Research Lab at Technical University of Madrid, in which climatic agents and those derived from the rig/maneuvering setup and the structural design were included. The particular case of Campamento's drydock, in Algeciras Bay (Spain), has been used to apply and validate the methodology. SRECMOCOS Project conjugates control, monitoring and wireless communication systems in a real time basis, offering the possibility to register and simulate all the parameters involved in port operations. This approach offers a step forward into a monitoring strategy to be included in monitoring

  2. Operation Characteristics Optimization of Low Power Three-Phase Asynchronous Motors

    Directory of Open Access Journals (Sweden)

    VLAD, I.

    2014-02-01

    Full Text Available Most published papers on low power asynchronous motors were aimed to achieve better operational performances in different operating conditions. The optimal design of the general-purpose motors requires searching and selecting an electric machine to meet minimum operating costs criterion and certain customer imposed restrictive conditions. In this paper, there are many significant simulations providing qualitative and quantitative information on reducing active and reactive energy losses in motors, and on parameters and constructive solution. The optimization study applied the minimal operating costs criterion, and it took into account the starting restrictive conditions. Thirteen variables regarding electromagnetic stresses and main constructive dimensions were considered. The operating costs of the optimized motor decreased with 25.6%, as compared to the existing solution. This paper can be a practical and theoretical support for the development and implementation of modern design methods, based on theoretical and experimental study of stationary and transient processes in low power motors, to increase efficiency and power factor.

  3. Dynamic Performance Characteristics of a Curved Slider Bearing Operating with Ferrofluids

    Directory of Open Access Journals (Sweden)

    Udaya P. Singh

    2012-01-01

    Full Text Available In the present theoretical investigation, the effect of ferrofluid on the dynamic characteristics of curved slider bearings is presented using Shliomis model which accounts for the rotation of magnetic particles, their magnetic moments, and the volume concentration in the fluid. The modified Reynolds equation for the dynamic state of the bearing is obtained. The results of dynamic stiffness and damping characteristics are presented. It is observed that the effect of rotation of magnetic particles improves the stiffness and damping capacities of the bearings.

  4. Operational modal analysis via image based technique of very flexible space structures

    Science.gov (United States)

    Sabatini, Marco; Gasbarri, Paolo; Palmerini, Giovanni B.; Monti, Riccardo

    2013-08-01

    Vibrations represent one of the most important topics of the engineering design relevant to flexible structures. The importance of this problem increases when a very flexible system is considered, and this is often the case of space structures. In order to identify the modal characteristics, in terms of natural frequencies and relevant modal parameters, ground tests are performed. However, these parameters could vary due to the operative conditions of the system. In order to continuously monitor the modal characteristics during the satellite lifetime, an operational modal analysis is mandatory. This kind of analysis is usually performed by using classical accelerometers or strain gauges and by properly analyzing the acquired output. In this paper a different approach for the vibrations data acquisition will be performed via image-based technique. In order to simulate a flexible satellite, a free flying platform is used; the problem is furthermore complicated by the fact that the overall system, constituted by a highly rigid bus and very flexible panels, must necessarily be modeled as a multibody system. In the experimental campaign, the camera, placed on the bus, will be used to identify the eigenfrequencies of the vibrating structure; in this case aluminum thin plates simulate very flexible solar panels. The structure is excited by a hammer or studied during a fast attitude maneuver. The results of the experimental activity will be investigated and compared with respect to the numerical simulation obtained via a FEM-multibody software and the relevant results will be proposed and discussed.

  5. The characteristics of the combustion process occurring under real operating conditions of traction

    Science.gov (United States)

    Longwic, R.; Sander, P.

    2016-09-01

    The authors deal with the issues of the Diesel engine under dynamic conditions. The conditions of the dynamic operation of the engine have most frequently been mapped by the method of free acceleration of the engine caused by the change of the position of the fuel dose lever. The article presents the results of indication of the traction Diesel engine under real operating conditions. This allows for the use of a mobile system to indicate the AVL engine built in the vehicle in research. We analysed a number of thermodynamic parameters of the combustion process in various dynamic states, typical for the process of actual operation of the engine, such as working in start-up conditions and immediately after, working in conditions of acceleration and coasting. Formulated conclusions significantly expand the area of knowledge concerning the functioning of the internal combustion engine in dynamic conditions.

  6. Operative versus non-operative treatment in complex proximal humeral fractures: a meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Xie, Lin; Ding, Fan; Zhao, Zhigang; Chen, Yan; Xing, Danmou

    2015-01-01

    Whether operative treatment for complex proximal humeral fractures (CPHFs) has a greater benefit over non-operative treatment remains controversial. There is no consensus on the optimal treatment in elderly patients with CPHFs. This updated meta-analysis of randomized controlled trials (RCTs) aims to investigate whether operative treatment is superior to non-operative treatment in CPHFs. The authors searched RCTs in the electronic databases (Cochrane Central Register of Controlled Trials, PubMed, EMBASE, Medline, Embase, Springer Link, Web of Knowledge, OVID and Google Scholar) from their establishment to July 2015. Researches on operative and non-operative treatment for CPHFs were selected in this meta-analysis. The quality of all studies was assessed and effective data was pooled for this meta-analysis. Outcome measurements were functional status include constant scores (CS scores) and disabilities of the arm, shoulder and hand scores (DASH scores), total complication rates and healthy-related quality of life. The meta-analysis was performed with software revman 5.3. Nine articles with a total 518 patients (average age 70.93) met inclusion criteria. Patients were followed up for at least 1 year in all the studies. No statistical differences were found between operative and non-operative treatment in CS scores at 12 mo (months) [MD 1.06 95 % CI (-3.51, 5.62)] and 24 mo [MD -0.61 95 % CI (-5.87, 4.65)]. There are also no statistical differences between operative and non-operative treatment in DASH scores at 12 mo [MD -4.51 95 % CI (-13.49, 4.47)] and 24 mo [MD -7.43 95 % CI (-16.14, 1.27)]. Statistical differences were found between operative and non-operative treatment in total complication rates [RR 1.55, 95 % CI (1.24, 1.94)]. Statistical differences in EQ-5D at 24 mo [MD 0.15, 95 % CI (0.05, 0.24)] were found between operative and non-operative treatment but no statistical differences were found in ED-5D at 12 mo [MD 0.08, 95 % CI (-0.01, 0.17)], 15D at

  7. Development of human behavior analysis techniques. Analysis of stress effects on the cognitive operating work

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chul Jung; Park Jae Hee [Korea Research Institute of Standards and Science, Taejon (Korea, Republic of)

    1995-08-01

    PSFs(Performance Shaping Factors) and performance measures were selected to evaluate the operating tasks of nuclear power plant. Effects of PSFs on performance were studied on the basis of LOCA(Loss of Coolant Accident) and SGTR(Steam generator Tube Rupture) task analysis. The knowledge of relationship between PSFs and performance measures were represented as IF - THEN rule form. The result will be applied to the development of the cognitive operational simulator. (author). 64 refs.

  8. Characteristics of identifying linear dynamic models from impulse response data using Prony analysis

    Energy Technology Data Exchange (ETDEWEB)

    Trudnowski, D.J.

    1992-12-01

    The purpose of the study was to investigate the characteristics of fitting linear dynamic models to the impulse response of oscillatory dynamic systems using Prony analysis. Many dynamic systems exhibit oscillatory responses with multiple modes of oscillations. Although the underlying dynamics of such systems are often nonlinear, it is frequently possible and very useful to represent the system operating about some set point with a linear model. Derivation of such linear models can be done using two basic approaches: model the system using theoretical derivations and some linearization method such as a Taylor series expansion; or use a curve-fitting technique to optimally fit a linear model to specified system response data. Prony analysis belongs to the second class of system modeling because it is a method of fitting a linear model to the impulse response of a dynamic system. Its parallel formulation inherently makes it well suited for fitting models to oscillatory system data. Such oscillatory dynamic effects occur in large synchronous-generator-based power systems in the form of electromechanical oscillations. To study and characterize these oscillatory dynamics, BPA has developed computer codes to analyze system data using Prony analysis. The objective of this study was to develop a highly detailed understanding of the properties of using Prony analysis to fit models to systems with characteristics often encountered in power systems. This understanding was then extended to develop general ``rules-of-thumb`` for using Prony analysis. The general characteristics were investigated by performing fits to data from known linear models under controlled conditions. The conditions studied include various mathematical solution techniques; different parent system configurations; and a large variety of underlying noise characteristics.

  9. Characteristics of identifying linear dynamic models from impulse response data using Prony analysis

    Energy Technology Data Exchange (ETDEWEB)

    Trudnowski, D.J.

    1992-12-01

    The purpose of the study was to investigate the characteristics of fitting linear dynamic models to the impulse response of oscillatory dynamic systems using Prony analysis. Many dynamic systems exhibit oscillatory responses with multiple modes of oscillations. Although the underlying dynamics of such systems are often nonlinear, it is frequently possible and very useful to represent the system operating about some set point with a linear model. Derivation of such linear models can be done using two basic approaches: model the system using theoretical derivations and some linearization method such as a Taylor series expansion; or use a curve-fitting technique to optimally fit a linear model to specified system response data. Prony analysis belongs to the second class of system modeling because it is a method of fitting a linear model to the impulse response of a dynamic system. Its parallel formulation inherently makes it well suited for fitting models to oscillatory system data. Such oscillatory dynamic effects occur in large synchronous-generator-based power systems in the form of electromechanical oscillations. To study and characterize these oscillatory dynamics, BPA has developed computer codes to analyze system data using Prony analysis. The objective of this study was to develop a highly detailed understanding of the properties of using Prony analysis to fit models to systems with characteristics often encountered in power systems. This understanding was then extended to develop general rules-of-thumb'' for using Prony analysis. The general characteristics were investigated by performing fits to data from known linear models under controlled conditions. The conditions studied include various mathematical solution techniques; different parent system configurations; and a large variety of underlying noise characteristics.

  10. Analysis on Isolation Condenser Operation by Fukushima Daiichi Unit 1 Operators

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Man Cheol [Chungang University, Seoul (Korea, Republic of)

    2014-08-15

    Fukushima Daiichi nuclear accident resulted in the core damage in three reactors and the release of considerable amount of radioactive material to the environment, not to mention significant social impact and anti-nuclear atmosphere all around the world. This paper provides a review of the findings related to shift operators' operation of the isolation condenser in Unit 1 to examine shift operators' response to the situation. Based on the review of the findings, a situation assessment model was developed to analyze shift operators' understanding on whether core cooling was successfully performed in Unit 1 through the operation of isolation condenser. It was found that lack of information could be one of the main causes for the failure in core cooling by the IC in Unit 1. It is also recommended that the differences in the mathematical model for the situation assessment and that of the real operator need to be further investigated.

  11. The effect of operational conditions on the hydrodynamic characteristics of the sludge bed in UASB reactors

    NARCIS (Netherlands)

    Leitao, R.C.; Santaellla, S.T.; Haandel, van A.C.; Zeeman, G.; Lettinga, G.

    2011-01-01

    This work aims to evaluate the hydrodynamic properties of the sludge bed of Upflow Anaerobic Sludge Blanket (UASB) reactors based on its settleability and expansion characteristics. The methodologies used for the evaluation of the settleability of aerobic activated sludge, and for the expansibility

  12. Outcome of 132 consecutive reconstructive operations for intestinal fistula--staged operation without primary anastomosis improved outcome in retrospective analysis

    DEFF Research Database (Denmark)

    Runström, B; Hallböök, O; Nyström, P O

    2013-01-01

    AIM: To study factors that influenced healing and survival after attempted closure of enterocutaneous fistula. MATERIAL AND METHODS: Retrospective analysis of prospective data concerning 101 patients operated on 132 instances for 110 enterocutaneous fistulae at two hospitals. RESULTS: In all, 96...... (87%) of the 110 fistulae healed and 92 (91%) patients survived. A total of 9 patients with unhealed fistula died. Multivariate analysis revealed jaundice as an independent factor for both death and failed closure and operation without anastomosis as an independent positive factor for healing. Failure...... rate was lower after an operation with stoma without anastomosis (6 of 43, 14%) than after an operation with anastomosis (30 of 89, 34%) p = 0.0213. Of the 36 instances with unhealed fistula, 13 (36%) could be ascribed to inadvertent bowel lesions at the reconstructive operation. In addition...

  13. Identification of Historical Veziragasi Aqueduct Using the Operational Modal Analysis

    Directory of Open Access Journals (Sweden)

    E. Ercan

    2014-01-01

    Full Text Available This paper describes the results of a model updating study conducted on a historical aqueduct, called Veziragasi, in Turkey. The output-only modal identification results obtained from ambient vibration measurements of the structure were used to update a finite element model of the structure. For the purposes of developing a solid model of the structure, the dimensions of the structure, defects, and material degradations in the structure were determined in detail by making a measurement survey. For evaluation of the material properties of the structure, nondestructive and destructive testing methods were applied. The modal analysis of the structure was calculated by FEM. Then, a nondestructive dynamic test as well as operational modal analysis was carried out and dynamic properties were extracted. The natural frequencies and corresponding mode shapes were determined from both theoretical and experimental modal analyses and compared with each other. A good harmony was attained between mode shapes, but there were some differences between natural frequencies. The sources of the differences were introduced and the FEM model was updated by changing material parameters and boundary conditions. Finally, the real analytical model of the aqueduct was put forward and the results were discussed.

  14. Identification of Historical Veziragasi Aqueduct Using the Operational Modal Analysis

    Science.gov (United States)

    Ercan, E.; Nuhoglu, A.

    2014-01-01

    This paper describes the results of a model updating study conducted on a historical aqueduct, called Veziragasi, in Turkey. The output-only modal identification results obtained from ambient vibration measurements of the structure were used to update a finite element model of the structure. For the purposes of developing a solid model of the structure, the dimensions of the structure, defects, and material degradations in the structure were determined in detail by making a measurement survey. For evaluation of the material properties of the structure, nondestructive and destructive testing methods were applied. The modal analysis of the structure was calculated by FEM. Then, a nondestructive dynamic test as well as operational modal analysis was carried out and dynamic properties were extracted. The natural frequencies and corresponding mode shapes were determined from both theoretical and experimental modal analyses and compared with each other. A good harmony was attained between mode shapes, but there were some differences between natural frequencies. The sources of the differences were introduced and the FEM model was updated by changing material parameters and boundary conditions. Finally, the real analytical model of the aqueduct was put forward and the results were discussed. PMID:24511287

  15. Operational modal analysis of road-rail bridge

    Directory of Open Access Journals (Sweden)

    Cardoso M.

    2015-01-01

    Full Text Available In this paper, we describe an Operational Modal Analysis (OMA of the Bridge over the Tocantins River, a composite road-rail bridge located in the city of Marabá, state of Pará, northern Brazil. The bridge is part of the Carajás Railway, which is used by VALE Company to transport iron ore from “Serra dos Carajás”, the largest mineral reserve of the planet. The bridge has a length of 2310m, being the second longest road-rail bridge in Brazil. The study focused on the bridge central span (with 77 m of length and two adjacent spans (with 44 m of length. We employed Piezo-electric accelerometers to measure the dynamic response of the bridge under ambient excitation, which consisted of the passage of loaded and unloaded trains, road traffic, wind and river current. For modal identification, to avoid the influence of the train mass over the bridge system, we only considered acceleration signals of road traffic and signals corresponding to intervals after the passage of loaded trains, i.e., the study disregarded the intervals during which the trains were over the monitored spans. We obtained modal parameters through two identification methods: one in the time domain and other in the frequency domain. We also performed a comparative analysis between the experimental modal parameters, and the numerical results obtained with a finite element model provided by a third-part company.

  16. Statistical analysis of the operating parameters which affect cupola emissions

    Energy Technology Data Exchange (ETDEWEB)

    Davis, J.W.; Draper, A.B.

    1977-12-01

    A sampling program was undertaken to determine the operating parameters which affected air pollution emission from gray iron foundry cupolas. The experimental design utilized the analysis of variance routine. Four independent variables were selected for examination on the basis of previous work reported in the literature. These were: (1) blast rate; (2) iron-coke ratio; (3) blast temperature; and (4) cupola size. The last variable was chosen since it most directly affects melt rate. Emissions from cupolas for which concern has been expressed are particle matter and carbon monoxide. The dependent variables were, therefore, particle loading, particle size distribution, and carbon monoxide concentration. Seven production foundries were visited and samples taken under conditions prescribed by the experimental plan. The data obtained from these tests were analyzed using the analysis of variance and other statistical techniques where applicable. The results indicated that blast rate, blast temperature, and cupola size affected particle emissions and the latter two also affected the particle size distribution. The particle size information was also unique in that it showed a consistent particle size distribution at all seven foundaries with a sizable fraction of the particles less than 1.0 micrometers in diameter.

  17. Safety analysis, 200 Area, Savannah River Plant: Separations area operations

    Energy Technology Data Exchange (ETDEWEB)

    Perkins, W.C.; Lee, R.; Allen, P.M.; Gouge, A.P.

    1991-07-01

    The nev HB-Line, located on the fifth and sixth levels of Building 221-H, is designed to replace the aging existing HB-Line production facility. The nev HB-Line consists of three separate facilities: the Scrap Recovery Facility, the Neptunium Oxide Facility, and the Plutonium Oxide Facility. There are three separate safety analyses for the nev HB-Line, one for each of the three facilities. These are issued as supplements to the 200-Area Safety Analysis (DPSTSA-200-10). These supplements are numbered as Sup 2A, Scrap Recovery Facility, Sup 2B, Neptunium Oxide Facility, Sup 2C, Plutonium Oxide Facility. The subject of this safety analysis, the, Plutonium Oxide Facility, will convert nitrate solutions of {sup 238}Pu to plutonium oxide (PuO{sub 2}) powder. All these new facilities incorporate improvements in: (1) engineered barriers to contain contamination, (2) barriers to minimize personnel exposure to airborne contamination, (3) shielding and remote operations to decrease radiation exposure, and (4) equipment and ventilation design to provide flexibility and improved process performance.

  18. Transforms and Operators for Directional Bioimage Analysis: A Survey.

    Science.gov (United States)

    Püspöki, Zsuzsanna; Storath, Martin; Sage, Daniel; Unser, Michael

    2016-01-01

    We give a methodology-oriented perspective on directional image analysis and rotation-invariant processing. We review the state of the art in the field and make connections with recent mathematical developments in functional analysis and wavelet theory. We unify our perspective within a common framework using operators. The intent is to provide image-processing methods that can be deployed in algorithms that analyze biomedical images with improved rotation invariance and high directional sensitivity. We start our survey with classical methods such as directional-gradient and the structure tensor. Then, we discuss how these methods can be improved with respect to robustness, invariance to geometric transformations (with a particular interest in scaling), and computation cost. To address robustness against noise, we move forward to higher degrees of directional selectivity and discuss Hessian-based detection schemes. To present multiscale approaches, we explain the differences between Fourier filters, directional wavelets, curvelets, and shearlets. To reduce the computational cost, we address the problem of matching directional patterns by proposing steerable filters, where one might perform arbitrary rotations and optimizations without discretizing the orientation. We define the property of steerability and give an introduction to the design of steerable filters. We cover the spectrum from simple steerable filters through pyramid schemes up to steerable wavelets. We also present illustrations on the design of steerable wavelets and their application to pattern recognition.

  19. 7 CFR 42.140 - Operating Characteristic (OC) curves for on-line sampling and inspection.

    Science.gov (United States)

    2010-01-01

    ... defects in the sample. (e) The next plan that is listed in the column headed 6 for an AQL of 0.25 is a... total sample, the lot will be rejected. The other double sampling plans operate in a similar manner with... AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF...

  20. Operation Characteristics of Treating Surface Water with Polyvinylchloride Hollow Fiber Ultrafiltration Membrane

    Institute of Scientific and Technical Information of China (English)

    GUO Xiaoyan; ZHANG Zhenjia; FANG Lin; SU Liguo

    2006-01-01

    A pilot plant study on a polyvinylchloride hollow fiber ultrafiltration membrane process was conducted for treating surface water.The membrane system was operated in the dead-end filtration mode under different constant permeate fluxes.The results show that the optimized operation ( transmembrane pressure≤0.1 Mpa,filtration time≤30 min) with a hydraulic cleaning (30 s) and a chemical cleaning (30 min,the chemical cleaning was performed after 16 cycles of filtration ) en ures a quite steady flux (1 100 L/(m2·h · Mpa)) and good permeate quality (turbidity <0.1NTU ).A full-scale plant can be suggested to operate with a mixed strategy of constant permeate flux mode (transmembrane pressure ≤0.1 Mpa) and constant transmembrane pressure mode.When the temperature of raw water becomes below 5 ℃,a constant transmembrane pressure mode should be used; otherwise a constant permeate flux mode (transmembrane pressure ≤ 0.1 Mpa) can be operated.In this way,irreversible fouling of ultrafiltration membrane can be minimized to keep a stable flux and make the life of membrane longer.

  1. Outcome of 132 consecutive reconstructive operations for intestinal fistula--staged operation without primary anastomosis improved outcome in retrospective analysis.

    Science.gov (United States)

    Runström, B; Hallböök, O; Nyström, P O; Sjödahl, R; Olaison, G

    2013-01-01

    To study factors that influenced healing and survival after attempted closure of enterocutaneous fistula. Retrospective analysis of prospective data concerning 101 patients operated on 132 instances for 110 enterocutaneous fistulae at two hospitals. In all, 96 (87%) of the 110 fistulae healed and 92 (91%) patients survived. A total of 9 patients with unhealed fistula died. Multivariate analysis revealed jaundice as an independent factor for both death and failed closure and operation without anastomosis as an independent positive factor for healing. Failure rate was lower after an operation with stoma without anastomosis (6 of 43, 14%) than after an operation with anastomosis (30 of 89, 34%) p = 0.0213. Of the 36 instances with unhealed fistula, 13 (36%) could be ascribed to inadvertent bowel lesions at the reconstructive operation. In addition, univariate analysis revealed that patients with previous multiple laparotomies or with multiple operations for enterocutaneous fistula healed less likely and had higher mortality. A low serum albumin, high white blood cell count, high C-reactive protein concentration, high fistula output, total parenteral nutrition, and operation for recurrent fistula were associated with death together with long operation time and operative bleeding, both indicators of surgical complexity. Over time, staged surgery avoiding anastomosis increased from 27% to 57%. Mortality decreased from 12% to 6%, and healing increased from 73% to 94%. Chronic inflammation, malnutrition, and liver failure causing an impaired healing capacity are important reasons for failure. Staged operation without primary anastomosis may allow the patient to reverse this condition and improve outcome. The high surgical complexity is a negative factor that requires careful planning of the operation.

  2. Change in working characteristics of the steam turbine metal with operating time of more than 330000 hours

    Science.gov (United States)

    Gladshteyn, V. I.; Troitskiy, A. I.

    2017-01-01

    Research of a metal of the stop valve case (SVC) of the K-300-23.5 LMZ turbine (steel grade 15Kh1M1FL), destroyed after operation for 331000 hours, is performed. It's chemical composition and properties are determined as follows: a short-term mechanical tensile stress at 20°C and at elevated temperature, critical temperature, fragility, critical crack opening at elevated temperature, and long-term strength. Furthermore, nature of the microstructure, packing density of carbide particles and their size, and chemical composition of carbide sediment are estimated. A manifestation of metal properties for the main case components by comparison with a forecast of the respective characteristics made for the operating time of 331000 hours is tested. Property-time relationships are built for the forecast using statistical treatment of the test results for the samples cut out from more than 300 parts. Representativeness of the research results is proved: the statistical treatment of their differences are within the range of ±5%. It has been found that, after 150000 hours of operation, only the tensile strength insignificantly depends on the operating time at 20°C, whereas indicators of strength at elevated temperature significantly reduce, depending on the operating time. A brittle-to-ductile transition temperature (BDTT) raises, a critical notch opening changes in a complicated way, a long-term strength reduces. It has been found empirically that the limit of a long-term strength of the SVC metal at 540°C and the operating time of 105 hours is almost 1.6 times less than the required value in the as-delivered state. It is possible to evaluate a service life of the operating valves with the operating time of more than 330000 hours with respect to the long-term strength of the metal taking into account the actual temperature and stress. Guidelines for the control of similar parts are provided.

  3. Spectral characteristics analysis of red tide water in mesocosm experiment

    Science.gov (United States)

    Cui, Tingwei; Zhang, Jie; Zhang, Hongliang; Ma, Yi; Gao, Xuemin

    2003-05-01

    Mesocosm ecosystem experiment with seawater enclosed of the red tide was carried out from July to September 2001. We got four species of biology whose quantities of bion are dominant in the red tide. During the whole process from the beginning to their dying out for every specie, in situ spectral measurements were carried out. After data processing, characteristic spectra of red tide of different dominant species are got. Via comparison and analysis of characteristics of different spectra, we find that in the band region between 685 and 735 nanometers, spectral characteristics of red tide is apparently different from that of normal water. Compared to spectra of normal water, spectra of red tide have a strong reflectance peak in the above band region. As to spectra of red tide dominated by different species, the situations of reflectance peaks are also different: the second peak of Mesodinium rubrum spectrum lies between 726~732 nm, which is more than 21nm away from the other dominant species spectra"s Leptocylindrus danicus"s second spectral peak covers 686~694nm; that of Skeletonema costatum lies between 691~693 nm. Chattonella marina"s second spectral peak lies about 703~705 nm. Thus we can try to determine whether red tide has occurred according to its spectral data. In order to monitor the event of red tide and identify the dominant species by the application of the technology of hyperspectral remote sensing, acquiring spectral data of different dominant species of red tide as much as possible becomes a basic work to be achieved for spectral matching, information extraction and so on based on hyperspectral data.

  4. On the Analysis of Recurrence Characteristics at Variable Actions

    Directory of Open Access Journals (Sweden)

    Horea SANDI

    2011-07-01

    Full Text Available The paper is devoted to some methodological problems raised by the analysis of hazards due to variable actions having implications for the risk of damage to structures. The basic recurrence model used is that of Poissonian stochastic processes. The techniques of calibration of specific recurrence characteristics are discussed, adopting a critical point of view versus statistical analyses relying exclusively on data like annual maxima. The adoption of some types of distributions is critically discussed, from the point of view of their compatibility with the Poissonian model referred to. Only the Gumbel and Fréchet distributions are accepted as adequate for the purpose adopted. Starting from their common properties an unbounded family of distributions is proposed. This family makes it possible to adopt calibrations providing an approximation of unlimited closeness to observation samples. The case of a pluri-dimensional characterization of the randomness of observation data is then tackled, considering as an illustrative case the directional statistical analysis of sequences of wind events. Some specific expressions are proposed for the directional analysis, leading to a good approximation of observation samples. A case study relying on the expressions is then presented.

  5. A characteristic analysis of the fluidic muscle cylinder

    Science.gov (United States)

    Kim, Dong-Soo; Bae, Sang-Kyu; Hong, Sung-In

    2005-12-01

    The fluidic muscle cylinder consists of an air bellows tube, flanges and lock nuts. It's features are softness of material and motion, simplicity of structure, low production cost and high power efficiency. Recently, unlikely the pneumatic cylinder, the fluidic muscle cylinder without air leakage, stick slip, friction, and seal was developed as a new concept actuator. It has the characteristics such as light weight, low price, high response, durable design, long life, high power, high contraction, which is innovative product fulfilling RT(Robot Technology) which is one of the nation-leading next generation strategy technologies 6T as well as cleanness technology. The application fields of the fluidic muscle cylinder are so various like fatigue tester, brake, accelerator, high technology testing device such as driving simulator, precise position, velocity, intelligent servo actuator under special environment such as load controlling system, and intelligent robot. In this study, we carried out the finite element modeling and analysis about the main design variables such as contraction ration and force, diameter increment of fluidic muscle cylinder. On the basis of finite element analysis, the prototype of fluidic muscle cylinder was manufactured and tested. Finally, we compared the results between the test and the finite element analysis.

  6. Characteristic analysis and experimental evaluation of artificial pneumatic cylinder

    Science.gov (United States)

    Kim, Dong-Soo; Bae, Sang-Kyu; Choi, Kyung-Hyun

    2005-12-01

    The fluidic muscle cylinder consists of an air bellows tube, flanges and lock nuts. Its features are softness of material and motion, simplicity of structure, low production cost and high power efficiency. Recently, unlikely the pneumatic cylinder, the fluidic muscle cylinder without air leakage, stick slip, friction, and seal was developed as a new concept actuator. It has the characteristics such as light weight, low price, high response, durable design, long life, high power, high contraction, which is innovative product fulfilling RT(Robot Technology) which is one of the nation-leading next generation strategy technologies 6T as well as cleanness technology. The application fields of the fluidic muscle cylinder are so various like fatigue tester, brake, accelerator, high technology testing device such as driving simulator, precise position, velocity, intelligent servo actuator under special environment such as load controlling system, and intelligent robot. In this study, we carried out the finite element modeling and analysis about the main design variables such as contraction ration and force, diameter increment of fluidic muscle cylinder. On the basis of finite element analysis, the prototype of fluidic muscle cylinder was fabricated and tested. Finally, we compared the results between the test and the finite element analysis.

  7. Analysis and evaluation of operational data. Annual report, 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-01

    The United States Nuclear Regulatory Commission`s Office for Analysis and Evaluation of Operational Data (AEOD) has published reports of its activities since 1984. The first report covered January through June of 1984, and the second report covered July through December of 1984. After those first two semiannual reports, AEOD published annual reports of its activities from 1985 through 1993. Beginning with report for 1986, AEOD Annual Reports have been published as NUREG-1272. Beginning with the report for 1987, NUREG-1272 has been published in two parts, No. 1 covering power reactors and No. 2 covering nonreactors (changed to `nuclear materials` with the 1993 report). AEOD changed its annual report from a calendar year (CY) to a fiscal year report, and added part No. 3 covering technical training, beginning with the combined Annual Report for CY 1994 and fiscal year 1995, NUREG-1272, Vol. 9, Nos. 1-3. This report, NUREG-1272, Vol. 10, No. 2, covers nuclear materials and presents a review of the events and concerns associated with the use of licensed material in applications other than power reactores. NUREG-1272, Vol. 10, No. 1, covers power reactors and presents an overview of the fiscal year 1996 operating experience of the nuclear power industry from the NRC perspective. NUREG-1272, Vol. 10, No. 3, covers technical training and presents the activities of the Technical Training Center in support of the NRC`s mission. Throughout these reports, whenever information is presented for a calendar year, it is so designated. Fiscal year information is designated by the four digits of the fiscal year.

  8. ANALYSIS OF CAMOUFLAGE COVER SPECTRAL CHARACTERISTICS BY IMAGING SPECTROMETER

    Directory of Open Access Journals (Sweden)

    A. Y. Kouznetsov

    2016-03-01

    Full Text Available Subject of Research.The paper deals with the problems of detection and identification of objects in hyperspectral imagery. The possibility of object type determination by statistical methods is demonstrated. The possibility of spectral image application for its data type identification is considered. Method. Researching was done by means of videospectral equipment for objects detection at "Fregat" substrate. The postprocessing of hyperspectral information was done with the use of math model of pattern recognition system. The vegetation indexes TCHVI (Three-Channel Vegetation Index and NDVI (Normalized Difference Vegetation Index were applied for quality control of object recognition. Neumann-Pearson criterion was offered as a tool for determination of objects differences. Main Results. We have carried out analysis of the spectral characteristics of summer-typecamouflage cover (Germany. We have calculated the density distribution of vegetation indexes. We have obtained statistical characteristics needed for creation of mathematical model for pattern recognition system. We have shown the applicability of vegetation indices for detection of summer camouflage cover on averdure background. We have presented mathematical model of object recognition based on Neumann-Pearson criterion. Practical Relevance. The results may be useful for specialists in the field of hyperspectral data processing for surface state monitoring.

  9. Effect of different modifications of BEA-zeolites on operational characteristics of conductometric biosensor.

    Science.gov (United States)

    Kucherenko, I S; Soldatkin, Capital O Cyrillic О; Soy, E; Kirdeciler, K; Öztürk, S; Akata, B; Jaffrezic-Renault, N; Soldatkin, A P; Dzyadevych, S V

    2012-08-01

    Effect of different modifications of zeolite Na(+)-BEA on working characteristics of urease-based conductometric biosensor was studied. As the biosensor sensitive elements were used bioselective membranes based on urease and various zeolites immobilised with bovine serum albumin on the surface of conductometric transducers. Influence of zeolites on sensitivity of urea biosensor was investigated as well as reproducibility of biosensor signal and reproducibility of activity of the bioselective element after different variants of urease immobilisation on the surface of conductometric transducer. The biosensors based on zeolites (NH4(+)-BEA 30 and H(+)-BEA 30) were shown to be the most sensitive. Concentration of these zeolites in the bioselective membrane was optimized. Use of zeolites modified with methyl viologen and silver was ascertained to be of no prospect for urea conductometric biosensors. It was demonstrated that characteristics of urea biosensors can be regulated, varying zeolites modifications and their concentrations in bioselective membranes.

  10. Measurement of laser absorptivity for operating parameters characteristic of laser drilling regime

    OpenAIRE

    Schneider, Matthieu; Berthe, Laurent; Fabbro, Rémy; Muller, Maryse

    2008-01-01

    International audience; Laser drilling in the percussion regime is commonly used in the aircraft industry to drill sub-millimetre holes in metallic targets. Characteristic laser intensities in the range of 10 MW cm−2 are typically employed for drilling metallic targets. With these intensities the temperature of the irradiated matter is above the vaporization temperature and the drilling process is led by hydrodynamic effects. Although the main physical processes involved are identified, this ...

  11. Cardiac myxoma: clinical characteristics, surgical intervention, intra-operative challenges and outcome.

    Science.gov (United States)

    Abu Abeeleh, Mahmoud; Saleh, Suhayl; Alhaddad, Emad; Alsmady, Moaath; Alshehabat, Musa; Bani Ismail, Zuhair; Massad, Islam; Bani Hani, Amjad; Abu Halaweh, Sami

    2017-07-01

    The objectives of this retrospective study were to characterize the clinical presentation, diagnostic findings, surgical approaches, intra-operative challenges and complications following the surgical treatment of cardiac myxoma in two of the largest referral hospitals in Jordan. Medical records of all patients presented to the cardiology department during the period between 1984 and 2016 were reviewed. Criteria for inclusion in the study were: (1) patients who were presented for cardiac evaluation due to symptoms suggestive of a primary cardiac problem, (2) completed medical records, including results of echocardiography suggestive of intra-cardiac occupying mass, (3) the surgical operation was undertaken and intra-operative data was available, (4) a histological diagnosis of myxoma was available and (5) the discharge status and follow-up data were available for at least 2 years after initial surgery. A total of 27 patients fulfilled the criteria for inclusion in the study. The average age was 42 years. Thirteen of the patients were females and 14 patients were males. The most common clinical presentations were dyspnea (29.6%) and murmurs (22.2%). Non-specific signs, such as weight loss, fever, fatigue, arthralgia and anemia, were reported in 10 (37%) patients. Signs related to systemic embolization were reported in 9 (33.3%) of the patients, involving the upper and lower extremities (55.6%), brain ischemia and vision loss (54.4%). Tumors in all patients were successfully resected under cardiopulmonary bypass support. The tumor was pedunculated in 17 (62.9%) of the patients and the size of the tumors varied from 1 to 7 centimeters in diameter. The tumor was located in the left atrium in 21 patients (77.7%), in the right atrium in 4 patients (14.8%), in the right ventricular side of the septum in 1 patient (3.7%) and involving the tricuspid valve in 1 patient (3.7%). The left atrial approach was used in 3 patients, a right atrial approach in 4 patients and a bi

  12. Analysis of dispersion characteristics of long period fiber grating

    Science.gov (United States)

    Jain, Vishal; Pawar, Santosh; Kumbhaj, S.; Sen, P. K.

    2016-10-01

    Present work deals with theoretical analysis of dispersion characteristics of long period fiber grating using straight forward coupled mode theory. Simple analytical solutions are obtained for co propagating core and cladding modes under linear regime. These solutions are used to derive expressions for transmission coefficient (tLPG), phase (ϕL), delay (τρ) and group velocity dispersion (Dρ) for proposed grating structure. Attention is paid to study the delay response of the grating, by varrying physical parameters like incident wavelength and coupling strength of grating. Negative values of group delay for certain value of coupling strength shows that long period fiber can be used as dispersion compansator device in optical fiber communication link.

  13. Analytical reliability analysis of soil-water characteristic curve

    Directory of Open Access Journals (Sweden)

    Johari A.

    2016-01-01

    Full Text Available The Soil Water Characteristic Curve (SWCC, also known as the soil water-retention curve, is an important part of any constitutive relationship for unsaturated soils. Deterministic assessment of SWCC has received considerable attention in the past few years. However the uncertainties of the parameters which affect SWCC dictate that the problem is of a probabilistic nature rather than being deterministic. In this research, a Gene Expression Programming (GEP-based SWCC model is employed to assess the reliability of SWCC. For this purpose, the Jointly Distributed Random Variables (JDRV method is used as an analytical method for reliability analysis. All input parameters of the model which are initial void ratio, initial water content, silt and clay contents are set to be stochastic and modelled using truncated normal probability density functions. The results are compared with those of the Monte Carlo (MC simulation. It is shown that the initial water content is the most effective parameter in SWCC.

  14. Analysis on the characteristics of pulsed laser proximity fuze's echo

    Science.gov (United States)

    Wang, Kun; Chen, Huimin

    2011-06-01

    With the rapid development of semiconductor technology and laser technology, a kind of proximity fuze named pulsed laser proximity fuze has been applied. Compared with other fuzes, pulsed laser proximity fuze has high ranging precision and strong resistance to artificial active interference. It is an important development tendency of proximity fuze. The paper analyze the characteristic of target echo of laser signal, and then make theoretical analysis and calculation on the laser signal transmission in the smog. Firstly, use the pulse width of 10ns semiconductor laser fuze to do typical targets experiment, to get the echo information of target distance is 5m; then to do smog interference experiment, by comparing the pulse width amplitude and backscattering signal amplitude of laser fuze in simulation and experiment, analyzing the effect of anti-clutter, providing the evidence for the subsequent of circuit of signal amplification and processing.

  15. Characteristic Analysis and Design of Power Flow of Organizations

    Institute of Scientific and Technical Information of China (English)

    YonganZhang; HuaLiang

    2004-01-01

    This thesis has carried on comparative analysis to the power characteristic of 5 kinds of institutional framework of enterprises at first, and has carried on the survey to the domestic and international train of thought in the research about enterprise's power, then puts forward the basic contradiction in enterprises organization ("The contradictions of the complexity of management's target and people's limited reason") and essential feature ofcurrent enterprise's power ("Solidification of power"), and then has put forward new train of thought in the study of enterprise's power and organization ("flow of power"), finally has designed the way and direction that the power flowed in enterprises, Combining enterprise's life cycle theory and American scholar L.E.Greiner's model about organization development.

  16. Dimensional Analysis on Resistance Characteristics of Labyrinth Seals

    Institute of Scientific and Technical Information of China (English)

    HU Dongxu; JIA Li; YANG Lixin

    2014-01-01

    Experimental investigation of stepped and straight-through labyrinth seals was designed to study the sealing performance of two different typical labyrinth seals.In order to facilitate dimensional analysis on the flow resistance characteristics of labyrinth seals,the variable cross-section of the flow channels are considered as constant cross-section flow.The mechanical energy loss of flow caused by throttle turbulence intensity is considered as caused by friction along the way.The friction coefficient of stepped labyrinth seals is bigger than that of straight-through labyrinth seals by more than 40% for the same Reynolds number and the ratio of equivalent diameter and the seal length.The expression of friction coefficient f and fRe are obtained from experimental data.The verifications indicate that the expressions are highly accurate.The contribution to the total pressure drop of each tooth cavity gradually becomes less along the flow direction.

  17. Parameter analysis calculation on characteristics of portable FAST reactor

    Energy Technology Data Exchange (ETDEWEB)

    Otsubo, Akira; Kowata, Yasuki [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1998-06-01

    In this report, we performed a parameter survey analysis by using the analysis program code STEDFAST (Space, TErrestrial and Deep sea FAST reactor-gas turbine system). Concerning the deep sea fast reactor-gas turbine system, calculations with many variable parameters were performed on the base case of a NaK cooled reactor of 40 kWe. We aimed at total equipment weight and surface area necessary to remove heat from the system as important values of the characteristics of the system. Electric generation power and the material of a pressure hull were specially influential for the weight. The electric generation power, reactor outlet/inlet temperatures, a natural convection heat transfer coefficient of sea water were specially influential for the area. Concerning the space reactor-gas turbine system, the calculations with the variable parameters of compressor inlet temperature, reactor outlet/inlet temperatures and turbine inlet pressure were performed on the base case of a Na cooled reactor of 40 kWe. The first and the second variable parameters were influential for the total equipment weight of the important characteristic of the system. Concerning the terrestrial fast reactor-gas turbine system, the calculations with the variable parameters of heat transferred pipe number in a heat exchanger to produce hot water of 100degC for cogeneration, compressor stage number and the kind of primary coolant material were performed on the base case of a Pb cooled reactor of 100 MWt. In the comparison of calculational results for Pb and Na of primary coolant material, the primary coolant weight flow rate was naturally large for the former case compared with for the latter case because density is very different between them. (J.P.N.)

  18. Full vector modal analysis of microstructured optical fiber propagation characteristics

    Science.gov (United States)

    Zghal, Mourad; Bahloul, Faouzi; Chatta, Rihab; Attia, Rabah; Pagnoux, Dominique; Roy, Philippe; Melin, Gilles; Gasca, Laurent

    2004-10-01

    Microstructured optical fibers (MOFs) are optical fibers having a periodic air-silica cross-section. The air holes extend along the axis of the fiber for its entire length. The core of the fiber is formed by a missing hole in the periodic structure. Remarkable properties of MOFs have recently been reported. This paper presents new work in the modeling of the propagation characteristics of MOFs using the Finite Element Method (FEM) and the Galerkin Method (GM). This efficient electromagnetic simulation package provides a vectorial description of the electromagnetic fields and of the associated effective index. This information includes accurate determination of the spectral extent of the modes, cutoff properties and mode-field distributions. We show that FEM is well adapted for describing the fields at abrupt transitions of the refractive index while GM has the advantage to accurately analyze MOFs of significant complexity using only modest computational resources. This presentation will focus on the specific techniques required to determine single mode operation, dispersion properties and effective area through careful choice of the geometrical parameters of the fibers. We demonstrate that with suitable geometrical parameters, the zero dispersion wavelength can be shifted. This tool can also provide design criteria for fabricating MOFs and a corresponding map of effective area. This approach is validated by comparison with experimental results and measurements on actual MOFs fabricated at IRCOM and at Alcatel Research and Innovation Center.

  19. Degradation Characteristics of Aniline with Ozonation and Subsequent Treatment Analysis

    Directory of Open Access Journals (Sweden)

    Zhaoqian Jing

    2015-01-01

    Full Text Available Owing to the toxicity and low biodegradability of aniline in water, its removal usually needs high cost processes such as adsorption and advanced oxidation. The degradation characteristics of aniline during ozonation were studied. The influence of operation parameters such as contact time, initial concentration, ozone dosage, temperature, and pH was also investigated. With ozone dosage of 22 mg/L, neutral pH, and room temperature, the ozonation removed aniline efficiently. After two hours’ ozonation, aniline removal reached 93.57%, and the corresponding COD removal was 31.03%, which indicated most of aniline was transformed into intermediates. At alkaline conditions, the aniline was more susceptible to being removed by ozonation owing to more hydroxyl radicals’ production. The results of GC-MS indicated many intermediates appeared during the process of ozonation such as butane diacid, oxalic acid, and formic acid. The intermediates produced during ozonation were more biodegradable than aniline; thus the ozonation of such organic compounds as aniline could be integrated with biological processes for further removal.

  20. Laboratory assessment of thermal characteristics of three phacoemulsification tip designs operated using torsional ultrasound.

    Science.gov (United States)

    Zacharias, Jaime

    2016-01-01

    Ultrasound activation of phacoemulsification (phaco) tips can create considerable thermal energy that may increase the risk of tissue damage during cataract surgery. The purpose of this study was to define the thermal profiles of three phaco tip designs in simulated surgical conditions. In this laboratory investigation, sleeved phaco tips (mini-flared Kelman(®) tip with aspiration bypass port and Intrepid(®) Balanced Tip with aspiration bypass port, and MST A1 bent-mini phaco tip (without aspiration bypass) were tested using an ultrasonic phaco device operated in torsional mode at power levels of 50%, 75%, and 100% amplitude. An automated fixture applied a 30 g load to simulate compression against the incision site, leading to friction between the silicone sleeve and the titanium tip. Temperature was recorded by high rate infrared imaging under conditions of free flow and occlusion, which was simulated by clamping the aspiration line. Data were summarized using descriptive statistics. Baseline temperatures of ~26°C were observed for all tips. During ultrasonic operation at 50%, 75%, and 100% amplitude, temperatures were lower for the mini-flared and balanced tips versus the bent-mini tip, both when load was applied and during occlusion. The bent-mini tip reached temperatures as high as 70°C during occlusion with load when operated at 100% amplitude, whereas the mini-flared tip remained tip remained tips, temperature increases during operation were not markedly different from free flow and no-load conditions when occlusion or frictional events were simulated. In all experiments for each tip design, increasing ultrasound power was associated with greater increases in tip temperature. Tip temperatures increased with applied load, but marked temperature increases during occlusion were observed only with the bent-mini tip. The balanced tip produced minimal thermal peaks in all tests.

  1. Performance and Operating Characteristics of a Novel Positive-Displacement Oil-Free CO2 Compressor

    OpenAIRE

    Kurtulus, Orkan; YANG Bin; Lumpkin, Dominique; Eckhard A. Groll; Jestings, Lee; Conde, Ricardo

    2014-01-01

    Research activities towards developing CO2 compressors have increased drastically during the last couple years. Since the transcritical CO2 cycle operates at much higher absolute pressures as compared to the conventional vapor compression cycles, it is necessary to develop new compressors or modify existing ones. In this paper, a novel positive-displacement oil-free CO2 compressor will be introduced. The compressor’s mechanical linkage system will be described. In addition, preliminary compre...

  2. Response monitoring and action limits: use of ADC numbers in understanding the operational characteristics of the Beckman ASTRA chemistry system.

    Science.gov (United States)

    Kessner, A; Burnett, R W; Bowers, G N

    1981-07-01

    The Beckman ASTRA is a microprocessor-controlled multichannel chemistry analyzer. The output of each module is available to the operator as analog-to-digital conversion (ADC) numbers, which we record during each calibration (Response Monitoring). After so studying three instruments for a total of 33 months, we have established limits for Calibrator ADC numbers that indicate possible operator action (Action Limits). These Action Limits are tighter than the microprocessor's programmed limits, and alert the operator to short- and long-term drift. These tighter limits warn of (a) impending failure of the instrument to calibrate or (b) possible inaccuracies in results for patients. We have instituted changes in preventive maintenance based on our studies of each module's operational characteristics, and have replaced electrodes that failed to meet our Response Monitoring specifications. Response Monitoring and Action Limits based upon ADC numbers have significantly enhanced our understanding of the ASTRA system and thus improved its operational efficiency and analytical reliability. Estimates of precision and accuracy (true value) were satisfactory in comparison to our prior single-channel continuous-flow and flame photometry analytical measurement systems.

  3. Acoustical Characteristics of Mastication Sounds: Application of Speech Analysis Techniques

    Science.gov (United States)

    Brochetti, Denise

    Food scientists have used acoustical methods to study characteristics of mastication sounds in relation to food texture. However, a model for analysis of the sounds has not been identified, and reliability of the methods has not been reported. Therefore, speech analysis techniques were applied to mastication sounds, and variation in measures of the sounds was examined. To meet these objectives, two experiments were conducted. In the first experiment, a digital sound spectrograph generated waveforms and wideband spectrograms of sounds by 3 adult subjects (1 male, 2 females) for initial chews of food samples differing in hardness and fracturability. Acoustical characteristics were described and compared. For all sounds, formants appeared in the spectrograms, and energy occurred across a 0 to 8000-Hz range of frequencies. Bursts characterized waveforms for peanut, almond, raw carrot, ginger snap, and hard candy. Duration and amplitude of the sounds varied with the subjects. In the second experiment, the spectrograph was used to measure the duration, amplitude, and formants of sounds for the initial 2 chews of cylindrical food samples (raw carrot, teething toast) differing in diameter (1.27, 1.90, 2.54 cm). Six adult subjects (3 males, 3 females) having normal occlusions and temporomandibular joints chewed the samples between the molar teeth and with the mouth open. Ten repetitions per subject were examined for each food sample. Analysis of estimates of variation indicated an inconsistent intrasubject variation in the acoustical measures. Food type and sample diameter also affected the estimates, indicating the variable nature of mastication. Generally, intrasubject variation was greater than intersubject variation. Analysis of ranks of the data indicated that the effect of sample diameter on the acoustical measures was inconsistent and depended on the subject and type of food. If inferences are to be made concerning food texture from acoustical measures of mastication

  4. Machine learning-based receiver operating characteristic (ROC) curves for crisp and fuzzy classification of DNA microarrays in cancer research.

    Science.gov (United States)

    Peterson, Leif E; Coleman, Matthew A

    2008-01-01

    Receiver operating characteristic (ROC) curves were generated to obtain classification area under the curve (AUC) as a function of feature standardization, fuzzification, and sample size from nine large sets of cancer-related DNA microarrays. Classifiers used included k nearest neighbor (kNN), näive Bayes classifier (NBC), linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), learning vector quantization (LVQ1), logistic regression (LOG), polytomous logistic regression (PLOG), artificial neural networks (ANN), particle swarm optimization (PSO), constricted particle swarm optimization (CPSO), kernel regression (RBF), radial basis function networks (RBFN), gradient descent support vector machines (SVMGD), and least squares support vector machines (SVMLS). For each data set, AUC was determined for a number of combinations of sample size, total sum[-log(p)] of feature t-tests, with and without feature standardization and with (fuzzy) and without (crisp) fuzzification of features. Altogether, a total of 2,123,530 classification runs were made. At the greatest level of sample size, ANN resulted in a fitted AUC of 90%, while PSO resulted in the lowest fitted AUC of 72.1%. AUC values derived from 4NN were the most dependent on sample size, while PSO was the least. ANN depended the most on total statistical significance of features used based on sum[-log(p)], whereas PSO was the least dependent. Standardization of features increased AUC by 8.1% for PSO and -0.2% for QDA, while fuzzification increased AUC by 9.4% for PSO and reduced AUC by 3.8% for QDA. AUC determination in planned microarray experiments without standardization and fuzzification of features will benefit the most if CPSO is used for lower levels of feature significance (i.e., sum[-log(p)] ~ 50) and ANN is used for greater levels of significance (i.e., sum[-log(p)] ~ 500). When only standardization of features is performed, studies are likely to benefit most by using CPSO for low levels

  5. Post-operative antibiotics after appendectomy and post-operative abscess development: a retrospective analysis.

    Science.gov (United States)

    Hughes, Michael J; Harrison, Ewen; Paterson-Brown, Simon

    2013-02-01

    Appendectomy is one of the most common emergency operations. Prophylaxis against infective complications involves post-operative antibiotics. There is no consensus as to the optimum antibiotic regimen. This study aimed to assess the relation between the duration of the post-operative antibiotic administration and intra-abdominal infections (IAIs). All patients who underwent appendectomy between September 1, 2009, and August 31, 2010, were identified. The appearance of the appendix at operation, post-operative antibiotics, white blood cell count, and temperature at the time of conversion of intravenous (IV) to oral antibiotics were compiled. IAIs were assessed as the final outcome. Two hundred sixty six patients underwent appendectomy-188 for simple appendicitis and 78 for complicated appendicitis. There were 18 IAIs (6.8%) overall, 10 (12.8%) after complicated appendicitis and eight (4.2%) after simple appendicitis. Prolonging antibiotics beyond the operation in the simple appendicitis group did not alter the incidence of IAI. Similarly, in the complicated appendicitis group, prolonging antibiotics beyond five days did not alter the incidence of IAI. Furthermore, in patients with complicated appendicitis, the presence of leukocytosis, fever, or both when IV antibiotics were converted to oral drugs was associated with the development of IAI (p=0.013). In simple appendicitis, post-operative antibiotics may not be beneficial at all. In complicated appendicitis, prolonging the course of antibiotics was not associated with a reduced IAI rate. However, cessation of IV antibiotics when fever or leukocytosis was present was associated with IAI development.

  6. Analysis of the Noise Characteristics of CMOS Current Conveyors

    DEFF Research Database (Denmark)

    Bruun, Erik

    1997-01-01

    The definition of the current conveyor is reviewed and a multiple-output second generation current conveyor (CCII) is shown to combine the different generations of current conveyors presently existing. Next, noise sources are introduced, and a general noise model for the current conveyor...... is described. This model is used for the analysis of selected examples of current conveyor based operational amplifier configurations and the noise performance of these configurations is compared. Finally, the noise model is developed for a CMOS current conveyor implementation, and approaches...... to an optimization of the noise performance are discussed. It is concluded that a class AB implementation can yield a lower noise output for the same dynamic range than a class A implementation. For both the class A implementation and the class AB implementation it is essential to design low noise current mirrors...

  7. Turnaround operations analysis for OTV. Volume 2: Detailed technical report

    Science.gov (United States)

    1988-01-01

    The objectives and accomplishments were to adapt and apply the newly created database of Shuttle/Centaur ground operations. Previously defined turnaround operations analyses were to be updated for ground-based OTVs (GBOTVs) and space-based OTVs (SBOTVs), design requirements identified for both OTV and Space Station accommodations hardware, turnaround operations costs estimated, and a technology development plan generated to develop the required capabilities. Technical and programmatic data were provided for NASA pertinent to OTV round and space operations requirements, turnaround operations, task descriptions, timelines and manpower requirements, OTV modular design and booster and Space Station interface requirements. SBOTV accommodations development schedule, cost and turnaround operations requirements, and a technology development plan for ground and space operations and space-based accommodations facilities and support equipment. Significant conclusion are discussed.

  8. Task Analysis of Emergency Operating Procedures for Generating Quantitative HRA Data

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yochan; Park, Jinkyun; Kim, Seunghwan; Choi, Sun Yeong; Jung, Wondea; Jang, Inseok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    In this paper, the analysis results of the emergency task in the procedures (EOPs; emergency operating procedures) that can be observed from the simulator data are introduced. The task type, component type, system type, and additional information related with the performance of the operators were described. In addition, a prospective application of the analyzed information to HEP quantification process was discussed. In the probabilistic safety analysis (PSA) field, various human reliability analyses (HRAs) have been performed to produce estimates of human error probabilities (HEPs) for significant tasks in complex socio-technical systems. To this end, Many HRA methods have provided basic or nominal HEPs for typical tasks and the quantitative relations describing how a certain performance context or performance shaping factors (PSFs) affects the HEPs. In the HRA community, however, the necessity of appropriate and sufficient human performance data has been recently indicated. This is because a wide range of quantitative estimates in the previous HRA methods are not supported by solid empirical bases. Hence, there have been attempts to collect HRA supporting data. For example, KAERI has started to collect information on both unsafe acts of operators and the relevant PSFs. A characteristic of the database that is being developed at KAERI is that human errors and related PSF surrogates that can be objectively observable are collected from full-scope simulator experiences. In this environment, to produce concretely grounded bases of the HEPs, the traits or attributes of tasks where significant human errors can be observed should be definitely determined. The determined traits should be applicable to compare the HEPs on the traits with the data in previous HRA methods or databases. In this study, task characteristics in a Westinghouse type of EOPs were analyzed with the defining task, component, and system taxonomies.

  9. Operational characteristics in the three-phase transformer-type SFCL with neutral line based on sequential reclosing process

    Science.gov (United States)

    Cho, Y. S.; Choi, H. S.; Jung, B. I.

    2011-11-01

    In a transformer-type superconducting fault current limiter (SFCL) with a neutral line, which is connected between the superconducting elements and secondary windings, we verified that the SFCL has excellent characteristics that induce the perfect simultaneous quench of the superconducting elements in the previous study. The application of the SFCL to the power networks requires its coordination with the reclosing operation duty, which protects a circuit. In this study, the fault current limiting and recovery characteristics of superconducting elements in the three-phase transformer-type SFCL with the neutral line were analyzed. The limiting rate of the fault current in the transformer-type SFCL could increased by an iron core, which allows quenching of the superconducting elements in a sound phase as well as in a faulted phase. In addition, the simultaneous quench led to uniform burdens on superconducting elements, all of which recovered their superconducting state within an opening cycle of a circuit breaker. Thus, the transformer-type SFCL with the neutral line could reliably conduct the fault current limiting and recovery operations of superconducting elements according to the reclosing operation duty and fault types.

  10. Analysis of trust in autonomy for convoy operations

    Science.gov (United States)

    Gremillion, Gregory M.; Metcalfe, Jason S.; Marathe, Amar R.; Paul, Victor J.; Christensen, James; Drnec, Kim; Haynes, Benjamin; Atwater, Corey

    2016-05-01

    With growing use of automation in civilian and military contexts that engage cooperatively with humans, the operator's level of trust in the automated system is a major factor in determining the efficacy of the human-autonomy teams. Suboptimal levels of human trust in autonomy (TiA) can be detrimental to joint team performance. This mis-calibrated trust can manifest in several ways, such as distrust and complete disuse of the autonomy or complacency, which results in an unsupervised autonomous system. This work investigates human behaviors that may reflect TiA in the context of an automated driving task, with the goal of improving team performance. Subjects performed a simulated leaderfollower driving task with an automated driving assistant. The subjects had could choose to engage an automated lane keeping and active cruise control system of varying performance levels. Analysis of the experimental data was performed to identify contextual features of the simulation environment that correlated to instances of automation engagement and disengagement. Furthermore, behaviors that potentially indicate inappropriate TiA levels were identified in the subject trials using estimates of momentary risk and agent performance, as functions of these contextual features. Inter-subject and intra-subject trends in automation usage and performance were also identified. This analysis indicated that for poorer performing automation, TiA decreases with time, while higher performing automation induces less drift toward diminishing usage, and in some cases increases in TiA. Subject use of automation was also found to be largely influenced by course features.

  11. Dispersion analysis of passive surface-wave noise generated during hydraulic-fracturing operations

    Science.gov (United States)

    Forghani-Arani, Farnoush; Willis, Mark; Snieder, Roel; Haines, Seth S.; Behura, Jyoti; Batzle, Mike; Davidson, Michael

    2014-01-01

    Surface-wave dispersion analysis is useful for estimating near-surface shear-wave velocity models, designing receiver arrays, and suppressing surface waves. Here, we analyze whether passive seismic noise generated during hydraulic-fracturing operations can be used to extract surface-wave dispersion characteristics. Applying seismic interferometry to noise measurements, we extract surface waves by cross-correlating several minutes of passive records; this approach is distinct from previous studies that used hours or days of passive records for cross-correlation. For comparison, we also perform dispersion analysis for an active-source array that has some receivers in common with the passive array. The active and passive data show good agreement in the dispersive character of the fundamental-mode surface-waves. For the higher mode surface waves, however, active and passive data resolve the dispersive properties at different frequency ranges. To demonstrate an application of dispersion analysis, we invert the observed surface-wave dispersion characteristics to determine the near-surface, one-dimensional shear-wave velocity.

  12. Placement of sensors in operational modal analysis for truss bridges

    Science.gov (United States)

    Debnath, N.; Dutta, A.; Deb, S. K.

    2012-08-01

    A modal approach is considered for sensor placement evaluation in operational modal analysis (OMA) where modal participation at individual degree of freedom (DOF) is evaluated separately for the target modes and subsequently locations are identified using these participation profiles. Modal contribution in output energy (MCOE) is proposed as modal measure to evaluate modal participation and has been applied in this modal approach framework for sensor placement evaluation. MCOE is evaluated using observability grammian for any types of response measurement (displacement, velocity or acceleration), while a system is released from any initial condition. Further, existing modal measures e.g. modal Hankel singular value (MHSV) and system norms (H2, H∞ and Hankel) are explained in perspective of OMA. To understand the efficiency of this proposed technique, MCOE is compared in terms of modal participation with existing modal measures as well as with other techniques like effective independence (EI) and modal kinetic energy (MKE). Analytical similarity is found for participation of a mode with EI method. Further, an existing large truss bridge structure is considered for comparative study based on modal participation of individual target modes along each DOF with acceleration measurement. In this comparison, MCOE technique is found to be in very good agreement with EI method as expected, while good agreement is observed with MHSV as well as norms and reasonable agreement with MKE method. Further, the adopted modal approach uses a flexible and insightful methodology for sensor location evaluation for multiple target modes.

  13. Fully Automated Operational Modal Analysis using multi-stage clustering

    Science.gov (United States)

    Neu, Eugen; Janser, Frank; Khatibi, Akbar A.; Orifici, Adrian C.

    2017-02-01

    The interest for robust automatic modal parameter extraction techniques has increased significantly over the last years, together with the rising demand for continuous health monitoring of critical infrastructure like bridges, buildings and wind turbine blades. In this study a novel, multi-stage clustering approach for Automated Operational Modal Analysis (AOMA) is introduced. In contrast to existing approaches, the procedure works without any user-provided thresholds, is applicable within large system order ranges, can be used with very small sensor numbers and does not place any limitations on the damping ratio or the complexity of the system under investigation. The approach works with any parametric system identification algorithm that uses the system order n as sole parameter. Here a data-driven Stochastic Subspace Identification (SSI) method is used. Measurements from a wind tunnel investigation with a composite cantilever equipped with Fiber Bragg Grating Sensors (FBGSs) and piezoelectric sensors are used to assess the performance of the algorithm with a highly damped structure and low signal to noise ratio conditions. The proposed method was able to identify all physical system modes in the investigated frequency range from over 1000 individual datasets using FBGSs under challenging signal to noise ratio conditions and under better signal conditions but from only two sensors.

  14. Metallurgical analysis of lithium test assembly operated for 1200 h

    Energy Technology Data Exchange (ETDEWEB)

    Furukawa, Tomohiro, E-mail: furukawa.tomohiro@jaea.go.jp [Japan Atomic Energy Agency, 4002 Narita, O-arai, Ibaraki 311-1393 (Japan); Kondo, Hiroo; Kanemura, Takuji; Hirakawa, Yasuhi [Japan Atomic Energy Agency, 4002 Narita, O-arai, Ibaraki 311-1393 (Japan); Yamaoka, Nobuo; Hoashi, Eiji; Suzuki-Yoshihashi, Sachiko; Horiike, Hiroshi [Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2014-10-15

    Highlights: • The assembly was used for the lithium free-surface flow experiments at 300 °C. • The integrity of steel was decreased due to carburizing from lithium. • It was proven that carbon control in lithium is important for corrosion protection. - Abstract: A lithium test assembly used for lithium-free surface flow experiments at 300 °C for 1200 h at Osaka University was analyzed metallographically to verify the design of the lithium target of the International Fusion Materials Irradiation Facility (IFMIF). Certain irregularities such as traces of high-speed lithium flow at a maximum velocity of 15 m/s were observed at the tip of the nozzle. Mottled unevenness with numerous microcracks a few microns deep was detected at the inlet of the nozzle, the velocity ratio of which was 0.1–0.4 as compared with the nozzle tip. A thin, altered layer developed on the surface of these regions because of carbide formation. It is believed that the microcracks were nucleated by thermal transients at the start or stop of operations of the lithium loop. These slight irregularities could be the result of exfoliation of the altered layer because of the high-speed lithium flow caused by the increased hardness of the altered layer as compared with that of the base metal. The metallurgical analysis proved for the first time that carbon control in lithium is also important for corrosion and erosion protection of the IFMIF components.

  15. The shape operator for differential analysis of images.

    Science.gov (United States)

    Avants, Brian; Gee, James

    2003-07-01

    This work provides a new technique for surface oriented volumetric image analysis. The method makes no assumptions about topology, instead constructing a local neighborhood from image information, such as a segmentation or edge map, to define a surface patch. Neighborhood constructions using extrinsic and intrinsic distances are given. This representation allows one to estimate differential properties directly from the image's Gauss map. We develop a novel technique for this purpose which estimates the shape operator and yields both principal directions and curvatures. Only first derivatives need be estimated, making the method numerically stable. We show the use of these measures for multi-scale classification of image structure by the mean and Gaussian curvatures. Finally, we propose to register image volumes by surface curvature. This is particularly useful when geometry is the only variable. To illustrate this, we register binary segmented data by surface curvature, both rigidly and non-rigidly. A novel variant of Demons registration, extensible for use with differentiable similarity metrics, is also applied for deformable curvature-driven registration of medical images.

  16. Exploring GPS Data for Operational Analysis of Farm Machinery

    Directory of Open Access Journals (Sweden)

    Ramin Shamshiri

    2013-04-01

    Full Text Available Global Positioning System (GPS has made a great evolution in different aspects of modern agricultural sectors. Today, a growing number of crop producers are using GPS and other modern electronic and computer equipments to practice Site Specific Management (SSM and precision agriculture. This technology has the potential in agricultural mechanization by providing farmers with a sophisticated tool to measure yield on much smaller scales as well as precisely determination and automatic storing of variables such as field time, working area, machine travel distance and speed, fuel consumption and yield information. This study focuses on how to interpret and process raw GPS data for operational analysis of farm machinery. Exact determinations of field activities using GPS data along with accurate measurements and records of yield provide an integrated tool to calculate field efficiency and field machine index which in turn increases machine productivity and labor saving. The results can also provide graphical tools for visualizing machine operator’s performance as well as making decision on field and machine size and selection.

  17. Advanced microgrid design and analysis for forward operating bases

    Science.gov (United States)

    Reasoner, Jonathan

    This thesis takes a holistic approach in creating an improved electric power generation system for a forward operating base (FOB) in the future through the design of an isolated microgrid. After an extensive literature search, this thesis found a need for drastic improvement of the FOB power system. A thorough design process analyzed FOB demand, researched demand side management improvements, evaluated various generation sources and energy storage options, and performed a HOMERRTM discrete optimization to determine the best microgrid design. Further sensitivity analysis was performed to see how changing parameters would affect the outcome. Lastly, this research also looks at some of the challenges which are associated with incorporating a design which relies heavily on inverter-based generation sources, and gives possible solutions to help make a renewable energy powered microgrid a reality. While this thesis uses a FOB as the case study, the process and discussion can be adapted to aide in the design of an off-grid small-scale power grid which utilizes high-penetration levels of renewable energy.

  18. ANALYSIS OF OPTIMUM OPERATING MODES OF POWER TRANSFORMERS UNDER OPERATING CONDITIONS

    Directory of Open Access Journals (Sweden)

    I. V. Khomenko

    2016-12-01

    Full Text Available Purpose. The study of parallel operation optimal modes of transformer equipment for a variety of operating conditions: same or different types of transformers, with or without reactive power flows. Methodology. Losses of energy in transformers make 30 % of all losses. Therefore the choice of the economically justified parallel operation of transformers is effective action to reduce losses. Typically, in the calculations of reactive power flows in the transformers are not taken into account. It is interesting to analyze the optimal operating conditions of transformers with and without reactive power flows. Results. Calculations for transformers in distribution networks showed that the inclusion of reactive power flows in transformers significant impact on the calculated optimum regimes of transformers.

  19. Using Micro-Synchrophasor Data for Advanced Distribution Grid Planning and Operations Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Emma [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kiliccote, Sila [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); McParland, Charles [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Roberts, Ciaran [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-07-01

    This report reviews the potential for distribution-grid phase-angle data that will be available from new micro-synchrophasors (µPMUs) to be utilized in existing distribution-grid planning and operations analysis. This data could augment the current diagnostic capabilities of grid analysis software, used in both planning and operations for applications such as fault location, and provide data for more accurate modeling of the distribution system. µPMUs are new distribution-grid sensors that will advance measurement and diagnostic capabilities and provide improved visibility of the distribution grid, enabling analysis of the grid’s increasingly complex loads that include features such as large volumes of distributed generation. Large volumes of DG leads to concerns on continued reliable operation of the grid, due to changing power flow characteristics and active generation, with its own protection and control capabilities. Using µPMU data on change in voltage phase angle between two points in conjunction with new and existing distribution-grid planning and operational tools is expected to enable model validation, state estimation, fault location, and renewable resource/load characterization. Our findings include: data measurement is outstripping the processing capabilities of planning and operational tools; not every tool can visualize a voltage phase-angle measurement to the degree of accuracy measured by advanced sensors, and the degree of accuracy in measurement required for the distribution grid is not defined; solving methods cannot handle the high volumes of data generated by modern sensors, so new models and solving methods (such as graph trace analysis) are needed; standardization of sensor-data communications platforms in planning and applications tools would allow integration of different vendors’ sensors and advanced measurement devices. In addition, data from advanced sources such as µPMUs could be used to validate models to improve

  20. Operational characteristics and non-inductive plasmas on NSTX-U

    Science.gov (United States)

    Mueller, Dennis

    2016-10-01

    Start-up and ramp-up of NSTX-U plasmas with nearly full solenoid pre-charge required higher loop voltage than on NSTX in agreement with modeling. NSTX-U has operated with a plasma current (Ip) of 0.65 MA at a toroidal field (BT) of 0.63 T for 2s in L-Mode. These plasmas allowed for the initial investigation of error field correction which found a difference between correction during Ip flattop and during ramp-up. Plasma control using feedback on the X-Point locations or the X-point height and outer strike point locations is routinely used. Because an ST does not have a single coil set that controls the inner gap, it was challenging to control the time at which the plasma diverted. A novel approach was used to trade off accuracy on the outer plasma shape to achieve a reproducible inner gap. These control tools allowed study of ELMy H-mode operation at Ip = 1 MA with boronized walls. A major long-term goal for NSTX-U is totally non-inductive operation. The plan calls for initiating the plasma with coaxial helicity injection (CHI) heatied by ECH, then current drive and heating by HHFW and NBI. CHI will be used in the new geometry to demonstrate results comparable to NSTX and provide information to inform plans to upgrade the available voltage from 1.65 to 2 kV next year. Low Ip plasmas will be used to study the dependence of current drive on neutral beam voltage and injection angle. Work Supported by U.S.D.O.E. Contract No. DE-AC02-09CH11466.

  1. [Physiological and hygienic characteristic of high-precision manufacturing operations in microelectronics].

    Science.gov (United States)

    Kirillov, V F; Mironov, A I; Gadakchan, K A; Mekhova, M M; Spiridonova, V S

    2010-01-01

    It was shown that workers performing high-precision manufacturing operations in microelectronic industry undergo severe visual, nervous and emotional stress combined with significant locomotor load, air deionization and deozonation, bacterial contamination, and UV deficit at their workplaces. These working conditions promote development of negative changes in the visual analyzer, nervous and emotional disorders, disturbances of systemic and regional hemodynamics. Also impaired is the functional state of the upper limb neuromuscular apparatus, central nervous and cardiovascular systems. The proposed certified complex of organizational, sanitary, hygienic, physiological, ergonomic, therapeutic and preventive measures has positive influence on the working capacity of employees in microelectronic industry.

  2. Laboratory assessment of thermal characteristics of three phacoemulsification tip designs operated using torsional ultrasound

    Directory of Open Access Journals (Sweden)

    Zacharias J

    2016-06-01

    Full Text Available Jaime Zacharias Phacodynamics Laboratory, Pasteur Ophthalmic Clinic, Santiago, Chile Purpose: Ultrasound activation of phacoemulsification (phaco tips can create considerable thermal energy that may increase the risk of tissue damage during cataract surgery. The purpose of this study was to define the thermal profiles of three phaco tip designs in simulated surgical conditions. Methods: In this laboratory investigation, sleeved phaco tips (mini-flared Kelman® tip with aspiration bypass port and Intrepid® Balanced Tip with aspiration bypass port, and MST A1 bent-mini phaco tip (without aspiration bypass were tested using an ultrasonic phaco device operated in torsional mode at power levels of 50%, 75%, and 100% amplitude. An automated fixture applied a 30 g load to simulate compression against the incision site, leading to friction between the silicone sleeve and the titanium tip. Temperature was recorded by high rate infrared imaging under conditions of free flow and occlusion, which was simulated by clamping the aspiration line. Data were summarized using descriptive statistics. Results: Baseline temperatures of ~26°C were observed for all tips. During ultrasonic operation at 50%, 75%, and 100% amplitude, temperatures were lower for the mini-flared and balanced tips versus the bent-mini tip, both when load was applied and during occlusion. The bent-mini tip reached temperatures as high as 70°C during occlusion with load when operated at 100% amplitude, whereas the mini-flared tip remained <50°C, and the balanced tip remained <36°C in all test conditions. For the mini-flared and balanced tips, temperature increases during operation were not markedly different from free flow and no-load conditions when occlusion or frictional events were simulated. Conclusion: In all experiments for each tip design, increasing ultrasound power was associated with greater increases in tip temperature. Tip temperatures increased with applied load, but marked

  3. [Comparative characteristic of methods for operative treatment of patients suffering varicocele].

    Science.gov (United States)

    Boĭko, M I; Pasiechnikov, S P; Boĭko, O M

    2014-04-01

    Efficacy and security of treatment of varicocele constitute a complex issues in urology, necessitating the additional investigations conduction. The results of surgical treatment of 280 patients, suffering left-sided varicocele and operated using three different methods--retroperitoneal varicocelectomy, laparoscopic varicocelectomy and subinguinal microsurgical varicocelectomy (SMV)--were analyzed. The advantages and faults of these methods were estimated, basing on the recurrence rate, complications by hidrocele occurrence and changes in the patients quality of life. SMV was determined as most effective and secure method of varicocele correction. The data obtained may be useful for choice of tactics for the disease treatment.

  4. ANALYSIS OF SWITCHGRASS CHARACTERISTICS USING NEAR INFRARED SPECTROSCOPY

    Directory of Open Access Journals (Sweden)

    Nicole Labbé

    2008-11-01

    Full Text Available Switchgrass varieties grown under various environments were investi-gated by dispersive and Fourier Transform Near-Infrared (NIR spectro-meters. The collected NIR spectra were analyzed using multivariate approaches. More specifically, principal component analysis (PCA and projection to latent structures (PLS regression techniques were employed to classify and predict characteristics of the switchgrass samples. The multivariate results were compared to reflectance indices that are commonly used to study the physiological performance of plants. From near infrared spectra, discrimination between the two growth locations was successfully achieved by PCA. Separation based on the ecotype and the rate of fertilizer applied to the field was also possible by the multivariable analysis of the spectral data. For the classification/ discrimination of the switchgrass samples, the near infrared spectra collected by the dispersive and the Fourier Transform spectrometers provided similar results. From the two near infrared data sets robust models were developed to predict non-structural carbohydrates content and the rate of nitrogen applied to the field. However, the spectra collected by the dispersive spectrometer resulted in more accurate models for these samples.

  5. Numerical investigation of refrigeration machine compressor operation considering single-phase electric motor dynamic characteristics

    Science.gov (United States)

    Baidak, Y.; Smyk, V.

    2017-08-01

    Using as the base the differential equations system which was presented in relative units for generalized electric motor of hermetic refrigeration compressor, mathematical model of the software for dynamic performance calculation of refrigeration machine compressors drive low-power asynchronous motors was developed. Performed on its ground calculations of the basic model of two-phase electric motor drive of hermetic compressor and the proposed newly developed model of the motor with single-phase stator winding, which is an alternative to the industrial motor winding, have confirmed the benefits of the motor with innovative stator winding over the base engine. Given calculations of the dynamic characteristics of compressor drive motor have permitted to determine the value of electromagnetic torque swinging for coordinating compressor and motor mechanical characteristics, and for taking them into consideration in choosing compressor elements construction materials. Developed and used in the process of investigation of refrigeration compressor drive asynchronous single-phase motor mathematical and software can be considered as an element of computer-aided design system for design of the aggregate of refrigeration compression unit refrigerating machine.

  6. Monetary targeting and financial system characteristics : An empirical analysis

    NARCIS (Netherlands)

    Samarina, A..

    2012-01-01

    This paper investigates how reforms and characteristics of the financial system affect the likelihood of countries to abandon their strategy of monetary targeting. Apart from financial system characteristics, we include macroeconomic, fiscal, and institutional factors potentially associated with cou

  7. Monetary targeting and financial system characteristics : An empirical analysis

    NARCIS (Netherlands)

    Samarina, A..

    2012-01-01

    This paper investigates how reforms and characteristics of the financial system affect the likelihood of countries to abandon their strategy of monetary targeting. Apart from financial system characteristics, we include macroeconomic, fiscal, and institutional factors potentially associated with

  8. Analysis of Radiation Exposure for Naval Personnel at Operation SANDSTONE.

    Science.gov (United States)

    1983-08-15

    Operation SANDSTONE Dose Reconstruction Methodology I I 2-1 Enewetak Atoll Anchorage Areas 14 2-2 Destroyer Patrol Sector Chart for Operation SANDSTONE 18...2-3 Average Free-Field Radiation Intensity for Southern and Northern Anchorage Areas - Enewetak Atoll 24 2-4 Average Free-Field Radiation Intensity...Operation SANDSTONE was the second nuclear test series held in the Marshall 0 Islands. It consisted of three nuclear weapon tests at Enewetak * Atoll in

  9. Analysis of Channel Luminosity Characteristics in Rocket-Triggered Lightning

    Institute of Scientific and Technical Information of China (English)

    LU Weitao; ZHANG Yijun; ZHOU Xiuji; MENG Qing; ZHENG Dong; MA Ming; WANG Fei; CHEN Shaodong; QIE Xiushu

    2008-01-01

    A comparison is made of the high-speed(2000 fps)photographic records in rocket-triggered negative lightning between two techniques.The analysis shows that:the initial speed of upward positive leader (UPL)in altitude-triggered negative lightning(ATNL)is about one order of magnitude less than that in classically triggered negative lightning(CTNL),while the triggering height of ATNL is higher than that of CTNL;the afterglow time of metal-vaporized part of the lightning channel Call endure for about 160-170 ms,thus the luminosity of the air-ionized part can reflect the characteristics of the current in the lightning channel better than that of the metal-vaporized part.According to the different characteristics of the luminosity change of the lightning channel,together with the observation of the electric field changes,three kinds of processes after return-stroke(RS)can be distinguished:the continuous decaying type without M component,the isolated type and the continuing type with M component,corresponding to different wave shapes of the continuous current.The geometric mean of the interval of RS with M component is 77 ms,longer than that(37 ms)of RS without M component.And the initial continuous current(ICC)with M component also has a longer duration compared to the ICC without M component.The distinction in the relative luminosity between the lightning channel before RS and that before M component is obvious:the former is very weak or even cannot be observed,while the latter is still considerably luminous.

  10. Influence of Compression Ratio on the Performance and Emission Characteristics of Annona Methyl Ester Operated DI Diesel Engine

    Directory of Open Access Journals (Sweden)

    Senthil Ramalingam

    2014-09-01

    Full Text Available This study aims to find the optimum performance and emission characteristics of single cylinder variable compression ratio (VCR engine with different blends of Annona methyl ester (AME as fuel. The performance parameters such as specific fuel consumption (SFC, brake thermal efficiency (BTE, and emission levels of HC, CO, Smoke, and NOx were compared with the diesel fuel. It is found that, at compression ratio of 17: 1 for A20 blended fuel (20% AME + 80% Diesel shows better performance and lower emission level which is very close to neat diesel fuel. The engine was operated with different values of compression ratio (15, 16, and 17 to find out best possible combination for operating engine with blends of AME. It is also found that the increase of compression ratio increases the BTE and reduces SFC and has lower emission without any engine in design modifications.

  11. Characteristics of atmospheric-pressure, radio-frequency glow discharges operated with argon added ethanol

    Science.gov (United States)

    Sun, Wen-Ting; Li, Guo; Li, He-Ping; Bao, Cheng-Yu; Wang, Hua-Bo; Zeng, Shi; Gao, Xing; Luo, Hui-Ying

    2007-06-01

    Rf, atmospheric-pressure glow discharge (APGD) plasmas with bare metal electrodes have promising prospects in the fields of plasma-aided etching, thin film deposition, disinfection and sterilization, etc. In this paper, the discharge characteristics are presented for the rf APGD plasmas generated with pure argon or argon-ethanol mixture as the plasma-forming gas and using water-cooled, bare copper electrodes. The experimental results show that the breakdown voltage can be reduced significantly when a small amount of ethanol is added into argon, probably due to the fact that the Penning ionization process is involved, and a pure α-mode discharge can be produced more easily with the help of ethanol. The uniformity of the rf APGDs of pure argon or argon-ethanol mixtures using bare metallic electrodes is identified with the aid of the intensified charge coupled device images.

  12. Characteristics of Speed Line Cutter and Fringe Analysis of Workpiece Surface

    Directory of Open Access Journals (Sweden)

    Shuai Wang

    2014-02-01

    Full Text Available Easy to operate, speed line cutter has a high machining cost performance, so is very popular among the majority of users. The precision of guide rails, screws and nuts used in most of the machines is not high, and the machine control cannot compensate for the screw pitch error, clearance during the transmission and machining error due to electrode wear. Furthermore, control signal may also be lost in control process. The development of speed line cutter focuses on the quality and machining stability of CNC speed line cutter. This article makes an analysis about the impact of machine’s inherent characteristics on machining workpiece surface, and concludes that analysis shall be made on the irregular fringe, therefore to heighten the machining precision.

  13. Entropy production analysis for hump characteristics of a pump turbine model

    Science.gov (United States)

    Li, Deyou; Gong, Ruzhi; Wang, Hongjie; Xiang, Gaoming; Wei, Xianzhu; Qin, Daqing

    2016-07-01

    The hump characteristic is one of the main problems for the stable operation of pump turbines in pump mode. However, traditional methods cannot reflect directly the energy dissipation in the hump region. In this paper, 3D simulations are carried out using the SST k- ω turbulence model in pump mode under different guide vane openings. The numerical results agree with the experimental data. The entropy production theory is introduced to determine the flow losses in the whole passage, based on the numerical simulation. The variation of entropy production under different guide vane openings is presented. The results show that entropy production appears to be a wave, with peaks under different guide vane openings, which correspond to wave troughs in the external characteristic curves. Entropy production mainly happens in the runner, guide vanes and stay vanes for a pump turbine in pump mode. Finally, entropy production rate distribution in the runner, guide vanes and stay vanes is analyzed for four points under the 18 mm guide vane opening in the hump region. The analysis indicates that the losses of the runner and guide vanes lead to hump characteristics. In addition, the losses mainly occur in the runner inlet near the band and on the suction surface of the blades. In the guide vanes and stay vanes, the losses come from pressure surface of the guide vanes and the wake effects of the vanes. A new insight-entropy production analysis is carried out in this paper in order to find the causes of hump characteristics in a pump turbine, and it could provide some basic theoretical guidance for the loss analysis of hydraulic machinery.

  14. Vibration and Operational Characteristics of a Composite-Steel (Hybrid) Gear

    Science.gov (United States)

    Handschuh, Robert F.; LaBerge, Kelsen E.; DeLuca, Samuel; Pelagalli, Ryan

    2014-01-01

    Hybrid gears have been tested consisting of metallic gear teeth and shafting connected by composite web. Both free vibration and dynamic operation tests were completed at the NASA Glenn Spur Gear Fatigue Test Facility, comparing these hybrid gears to their steel counterparts. The free vibration tests indicated that the natural frequency of the hybrid gear was approximately 800 Hz lower than the steel test gear. The dynamic vibration tests were conducted at five different rotational speeds and three levels of torque in a four square test configuration. The hybrid gears were tested both as fabricated (machined, composite layup, then composite cure) and after regrinding the gear teeth to the required aerospace tolerance. The dynamic vibration tests indicated that the level of vibration for either type of gearing was sensitive to the level of load and rotational speed.

  15. Operational characteristics of single-particle heat engines and refrigerators with time-asymmetric protocol

    Science.gov (United States)

    Pal, P. S.; Saha, Arnab; Jayannavar, A. M.

    2016-09-01

    We have studied the single-particle heat engine and refrigerator driven by time-asymmetric protocol of finite duration. Our system consists of a particle in a harmonic trap with time-periodic strength that drives the particle cyclically between two baths. Each cycle consists of two isothermal steps at different temperatures and two adiabatic steps connecting them. The system works in irreversible mode of operation even in the quasistatic regime. This is indicated by finite entropy production even in the large cycle time limit. Consequently, Carnot efficiency for heat engine or Carnot coefficient of performance (COP) for refrigerators is not achievable. We further analyzed the phase diagram of heat engines and refrigerators. They are sensitive to time-asymmetry of the protocol. Phase diagram shows several interesting features, often counterintuitive. The distribution of stochastic efficiency and COP is broad and exhibits power-law tails.

  16. Mobile Geospatial Information Systems for Land Force Operations: Analysis of Operational Needs and Research Opportunities

    Science.gov (United States)

    2010-03-01

    Task Analysis ( HTA ), Cognitive Work Analysis (CWA) Military battlefield awareness, wayfind*, terrain navigation, route guidance, reconnaissance...passwords, location of barriers/land lines and early warning devices. Once in an Observation Post, a rifleman scans by looking and listening for any... HTA – Hierarchical Task Analysis IED – Improvised Explosive Device ISSP – Integrated Soldier System Project LCol – Lieutenant Colonel MCpl

  17. Absolute stability analysis of linear systems with Duhem hysteresis operator

    NARCIS (Netherlands)

    Ouyang, Ruiyue; Jayawardhana, Bayu

    2014-01-01

    In this paper, we investigate the stability of positive and negative feedback interconnections of a linear system and a Duhem hysteresis operator. We provide sufficient conditions on the linear plant and on the Duhem operator which are based on the counterclockwise (CCW) or clockwise (CW) input–outp

  18. Air Cushion Vehicle Operator Training System (ACVOTS) Problem Analysis

    Science.gov (United States)

    1981-11-01

    Bays) - Close-in maneuvering (Long Point) - Overland operations (Crooked Island) - Open water operations (Gulf of Mexico ) Audio Visual Equipment...types of media are used to support their implementation. - programmed text/ storyboard text, - sound slide, - videotape, - computer based instruction...types which facilitate student knowledge learning. Examples of academic media include: instructor lecture, mediated lecture, storyboard text, program

  19. Analysis of Informal Credit Operations among Farmers In Atisbo ...

    African Journals Online (AJOL)

    The study explored the operations, (savings and loan procurement), as well as ... of the informal financial institutions in ATISBO Local Government Area of Oyo ... of group members, unsynchronized contributions to savings due to non-aligned ... into the operations of the Community Banks through the mobile rural banking ...

  20. Statistical analysis of regional capital and operating costs for electric power generation

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, L.R.; Myers, M.G.; Herrman, J.A.; Provanizano, A.J.

    1977-10-01

    This report presents the results of a three and one-half-month study conducted for Brookhaven National Lab. to develop capital and operating cost relationships for seven electric power generating technologies: oil-, coal-, gas-, and nuclear-fired steam-electric plants, hydroelectric plants, and gas-turbine plants. The methodology is based primarily on statistical analysis of Federal Power Commission data for plant construction and annual operating costs. The development of cost-output relationships for electric power generation is emphasized, considering the effects of scale, technology, and location on each of the generating processes investigated. The regional effects on cost are measured at the Census Region level to be consistent with the Brookhaven Multi-Regional Energy and Interindustry Regional Model of the United States. Preliminary cost relationships for system-wide costs - transmission, distribution, and general expenses - were also derived. These preliminary results cover the demand for transmission and distribution capacity and operating and maintenance costs in terms of system-service characteristics. 15 references, 6 figures, 23 tables.