Sample records for reliable reserve calculations

  1. The rating reliability calculator

    Solomon David J


    Full Text Available Abstract Background Rating scales form an important means of gathering evaluation data. Since important decisions are often based on these evaluations, determining the reliability of rating data can be critical. Most commonly used methods of estimating reliability require a complete set of ratings i.e. every subject being rated must be rated by each judge. Over fifty years ago Ebel described an algorithm for estimating the reliability of ratings based on incomplete data. While his article has been widely cited over the years, software based on the algorithm is not readily available. This paper describes an easy-to-use Web-based utility for estimating the reliability of ratings based on incomplete data using Ebel's algorithm. Methods The program is available public use on our server and the source code is freely available under GNU General Public License. The utility is written in PHP, a common open source imbedded scripting language. The rating data can be entered in a convenient format on the user's personal computer that the program will upload to the server for calculating the reliability and other statistics describing the ratings. Results When the program is run it displays the reliability, number of subject rated, harmonic mean number of judges rating each subject, the mean and standard deviation of the averaged ratings per subject. The program also displays the mean, standard deviation and number of ratings for each subject rated. Additionally the program will estimate the reliability of an average of a number of ratings for each subject via the Spearman-Brown prophecy formula. Conclusion This simple web-based program provides a convenient means of estimating the reliability of rating data without the need to conduct special studies in order to provide complete rating data. I would welcome other researchers revising and enhancing the program.

  2. Storage Reliability of Reserve Batteries


    batteries – Environmental concerns, lack of business – Non-availability of some critical materials • Lithium Oxyhalides are systems of choice – Good...exhibit good corrosion resistance to neutral electrolytes (LiAlCl4 in thionyl chloride and sulfuryl chloride ) • Using AlCl3 creates a much more corrosive...Storage Reliability of Reserve Batteries Jeff Swank and Allan Goldberg Army Research Laboratory Adelphi, MD 301-394-3116 ll l

  3. Electronics reliability calculation and design

    Dummer, Geoffrey W A; Hiller, N


    Electronics Reliability-Calculation and Design provides an introduction to the fundamental concepts of reliability. The increasing complexity of electronic equipment has made problems in designing and manufacturing a reliable product more and more difficult. Specific techniques have been developed that enable designers to integrate reliability into their products, and reliability has become a science in its own right. The book begins with a discussion of basic mathematical and statistical concepts, including arithmetic mean, frequency distribution, median and mode, scatter or dispersion of mea

  4. China's Ultimate Recoverable Reserves Calculated

    Fu Hong


    @@ A nationwide project is being launched to assess the potential capacity of China's oil and natural gas resources, a senior official from the Ministry of Land and Resources said in early December. Based on the existing data, China's oil and natural gas reserves are estimated at 106.9 billion tons and 53trillion cubic meters respectively at the present time.

  5. Reliability assessment of reserved water disposal with erodible fuse plug

    Kosichenko Yuriy Mikhaylovich

    Full Text Available Water disposal constructions are one of the most responsible constructions of reservoir hydrosystem, that’s why the a lot of attention was always paid to the problems of estimating and providing their reliability and safety. The most important function of such objects is providing reliability and safety of other hydraulic constructions and economic assets in afterbay and water head. The authors offer estimation method for reliability and faultless performance of reserved water disposal with erodible fuse plug on low-head water development. In order to estimate the reliability of reserved water disposal with erodible fuse plug the Bayesian treatment was used. The calculation of diagnoses (states of reserved water disposal isoffered in case of diagnostic properties k 1 and k 2. One of the main demands placed onreserved water disposals is erosion of soil plug in case of flood discharge exeedance over the estimated frequency with the full opening of the waste sluice.

  6. Calculation reliability in vehicle accident reconstruction.

    Wach, Wojciech


    The reconstruction of vehicle accidents is subject to assessment in terms of the reliability of a specific system of engineering and technical operations. In the article [26] a formalized concept of the reliability of vehicle accident reconstruction, defined using Bayesian networks, was proposed. The current article is focused on the calculation reliability since that is the most objective section of this model. It is shown that calculation reliability in accident reconstruction is not another form of calculation uncertainty. The calculation reliability is made dependent on modeling reliability, adequacy of the model and relative uncertainty of calculation. All the terms are defined. An example is presented concerning the analytical determination of the collision location of two vehicles on the road in the absence of evidential traces. It has been proved that the reliability of this kind of calculations generally does not exceed 0.65, despite the fact that the calculation uncertainty itself can reach only 0.05. In this example special attention is paid to the analysis of modeling reliability and calculation uncertainty using sensitivity coefficients and weighted relative uncertainty.

  7. Calculating reliability measures for ordinal data.

    Gamsu, C V


    Establishing the reliability of measures taken by judges is important in both clinical and research work. Calculating the statistic of choice, the kappa coefficient, unfortunately is not a particularly quick and simple procedure. Two much-needed practical tools have been developed to overcome these difficulties: a comprehensive and easily understood guide to the manual calculation of the most complex form of the kappa coefficient, weighted kappa for ordinal data, has been written; and a computer program to run under CP/M, PC-DOS and MS-DOS has been developed. With simple modification the program will also run on a Sinclair Spectrum home computer.

  8. Optimal reserve capacity allocation with consideration of customer reliability requirements

    Najafi, M. [Department of Engineering, Islamic Azad University, Science and Research Branch, Tehran (Iran); Ehsan, M.; Fotuhi-Firuzabad, M. [Department of Electrical Engineering, Sharif University of Technology, Tehran (Iran); Akhavein, A. [Department of Engineering, Islamic Azad University, Tehran South Branch (Iran); Afshar, K. [Department of Electrical Engineering, Imam Khomeini International University, Qazvin (Iran)


    An algorithm for determining optimal reserve capacity in a power market is presented in this paper. Optimization process in the proposed algorithm is based on the cost-benefit trade off. Market clearance is executed with consideration of uncertainties of power system components in an aggregated environment. It is assumed that both generating units and interruptible loads participate in the reserve market. In addition, customers' reliability requirements are considered as constraints for decision making process of ISO. The rendered method considers random outages of generating units and transmission lines and determined outage of interruptible loads and employs Monte Carlo Simulation (MCS) for scenarios generation. Unlike previous methods in which a constant value is assumed for cost of the energy not supplied, a flexible value for this parameter is applied which shows an important effect in the evaluation results. The performance of the proposed method has been examined on the IEEE-Reliability Test System (IEEE-RTS). (author)

  9. Towards reliable calculations of the correlation function

    Maj, Radoslaw; 10.1142/S0218301307009221


    The correlation function of two identical pions interacting via Coulomb potential is computed for a general case of anisotropic particle's source of finite life time. The effect of halo is taken into account as an additional particle's source of large spatial extension. Due to the Coulomb interaction, the effect of halo is not limited to very small relative momenta but it influences the correlation function in a relatively large domain. The relativistic effects are discussed in detail and it is argued that the calculations have to be performed in the center-of-mass frame of particle's pair where the (nonrelativistic) wave function of particle's relative motion is meaningful. The Bowler-Sinyukov procedure to remove the Coulomb interaction is tested and it is shown to significantly underestimate the source's life time.

  10. Calculation and Updating of Reliability Parameters in Probabilistic Safety Assessment

    Zubair, Muhammad; Zhang, Zhijian; Khan, Salah Ud Din


    The internal events of nuclear power plant are complex and include equipment maintenance, equipment damage etc. These events will affect the probability of the current risk level of the system as well as the reliability of the equipment parameter values so such kind of events will serve as an important basis for systematic analysis and calculation. This paper presents a method for reliability parameters calculation and their updating. The method is based on binomial likelihood function and its conjugate beta distribution. For update parameters Bayes' theorem has been selected. To implement proposed method a computer base program is designed which provide help to estimate reliability parameters.

  11. Lifeline system network reliability calculation based on GIS and FTA

    TANG Ai-ping; OU Jin-ping; LU Qin-nian; ZHANG Ke-xu


    Lifelines, such as pipeline, transportation, communication, electric transmission and medical rescue systems, are complicated networks that always distribute spatially over large geological and geographic units.The quantification of their reliability under an earthquake occurrence should be highly regarded, because the performance of these systems during a destructive earthquake is vital in order to estimate direct and indirect economic losses from lifeline failures, and is also related to laying out a rescue plan. The research in this paper aims to develop a new earthquake reliability calculation methodology for lifeline systems. The methodology of the network reliability for lifeline systems is based on fault tree analysis (FTA) and geological information system(GIS). The interactions existing in a lifeline system are considered herein. The lifeline systems are idealized as equivalent networks, consisting of nodes and links, and are described by network analysis in GIS. Firstly, the node is divided into two types: simple node and complicated node, where the reliability of the complicated node is calculated by FTA and interaction is regarded as one factor to affect performance of the nodes. The reliability of simple node and link is evaluated by code. Then, the reliability of the entire network is assessed based on GIS and FTA. Lastly, an illustration is given to show the methodology.

  12. Composite system reliability evaluation by stochastic calculation of system operation

    Haubrick, H.-J.; Hinz, H.-J.; Landeck, E. [Dept. of Power Systems and Power Economics (Germany)


    This report describes a new developed probabilistic approach for steady-state composite system reliability evaluation and its exemplary application to a bulk power test system. The new computer program called PHOENIX takes into consideration transmission limitations, outages of lines and power stations and, as a central element, a highly sophisticated model to the dispatcher performing remedial actions after disturbances. The kernel of the new method is a procedure for optimal power flow calculation that has been specially adapted for the use in reliability evaluations under the above mentioned conditions. (author) 11 refs., 8 figs., 1 tab.

  13. Ready, Reliable, and Relevant: The Army Reserve Component as an Operational Reserve


    33 Stephen Everett and L. Martin Kaplan, Department of the Army Historical Summary: Fiscal Year 1993, Center of...1992 and 1993, Public Law 102- 190, 102nd Cong. (December 5, 1991): 1352-1353. 35 Dennis Chapman , “Planning for Employment of the Reserve...not acronyms. These terms are referenced in Chapman , “Planning for Employment of the Reserve Components,” 1-4; 6-9; 11-12. 40 Chapman , “Planning

  14. Reliability/Cost Evaluation on Power System connected with Wind Power for the Reserve Estimation

    Lee, Go-Eun; Cha, Seung-Tae; Shin, Je-Seok;


    Wind power is ideally a renewable energy with no fuel cost, but has a risk to reduce reliability of the whole system because of uncertainty of the output. If the reserve of the system is increased, the reliability of the system may be improved. However, the cost would be increased. Therefore...... the reserve needs to be estimated considering the trade-off between reliability and economic aspects. This paper suggests a methodology to estimate the appropriate reserve, when wind power is connected to the power system. As a case study, when wind power is connected to power system of Korea, the effects...

  15. Impacts of Contingency Reserve on Nodal Price and Nodal Reliability Risk in Deregulated Power Systems

    Zhao, Qian; Wang, Peng; Goel, Lalit


    The deregulation of power systems allows customers to participate in power market operation. In deregulated power systems, nodal price and nodal reliability are adopted to represent locational operation cost and reliability performance. Since contingency reserve (CR) plays an important role...... in reliable operation, the CR commitment should be considered in operational reliability analysis. In this paper, a CR model based on customer reliability requirements has been formulated and integrated into power market settlement. A two-step market clearing process has been proposed to determine generation...... and CR allocation. Customers' nodal unit commitment risk and nodal energy interruption have been evaluated through contingency analysis. Customers' reliability cost including reserve service cost and energy interruption cost have also been evaluated....

  16. Fast and Reliable Primary Frequency Reserves From Refrigerators with Decentralized Stochastic Control

    Vrettos, Evangelos; Ziras, Charalampos; Andersson, Goran


    Due to increasing shares of renewable energy sources, more frequency reserves are required to maintain power system stability. In this paper, we present a decentralized control scheme that allows a large aggregation of refrigerators to provide Primary Frequency Control (PFC) reserves to the grid....... In addition, we propose a procedure to dynamically reset the thermostat temperature limits in order to provide reliable PFC reserves, as well as a corrective temperature feedback loop to build robustness to biased frequency deviations. Furthermore, we introduce an additional randomization layer...

  17. Assessing the reliability of calculated catalytic ammonia synthesis rates

    Medford, Andrew James; Wellendorff, Jess; Vojvodic, Aleksandra


    We introduce a general method for estimating the uncertainty in calculated materials properties based on density functional theory calculations. We illustrate the approach for a calculation of the catalytic rate of ammonia synthesis over a range of transition-metal catalysts. The correlation...

  18. Reliability sensitivity-based correlation coefficient calculation in structural reliability analysis

    Yang, Zhou; Zhang, Yimin; Zhang, Xufang; Huang, Xianzhen


    The correlation coefficients of random variables of mechanical structures are generally chosen with experience or even ignored, which cannot actually reflect the effects of parameter uncertainties on reliability. To discuss the selection problem of the correlation coefficients from the reliability-based sensitivity point of view, the theory principle of the problem is established based on the results of the reliability sensitivity, and the criterion of correlation among random variables is shown. The values of the correlation coefficients are obtained according to the proposed principle and the reliability sensitivity problem is discussed. Numerical studies have shown the following results: (1) If the sensitivity value of correlation coefficient ρ is less than (at what magnitude 0.000 01), then the correlation could be ignored, which could simplify the procedure without introducing additional error. (2) However, as the difference between ρ s, that is the most sensitive to the reliability, and ρ R , that is with the smallest reliability, is less than 0.001, ρ s is suggested to model the dependency of random variables. This could ensure the robust quality of system without the loss of safety requirement. (3) In the case of | E abs|>0.001 and also | E rel|>0.001, ρ R should be employed to quantify the correlation among random variables in order to ensure the accuracy of reliability analysis. Application of the proposed approach could provide a practical routine for mechanical design and manufactory to study the reliability and reliability-based sensitivity of basic design variables in mechanical reliability analysis and design.

  19. Reliability of Calculated Low-Density Lipoprotein Cholesterol.

    Meeusen, Jeffrey W; Snozek, Christine L; Baumann, Nikola A; Jaffe, Allan S; Saenger, Amy K


    Aggressive low-density lipoprotein cholesterol (LDL-C)-lowering strategies are recommended for prevention of cardiovascular events in high-risk populations. Guidelines recommend a 30% to 50% reduction in at-risk patients even when LDL-C concentrations are between 70 and 130 mg/dl (1.8 to 3.4 mmol/L). However, calculation of LDL-C by the Friedewald equation is the primary laboratory method for routine LDL-C measurement. We compared the accuracy and reproducibility of calculated LDL-C <130 mg/dl (3.4 mmol/L) to LDL-C measured by β quantification (considered the gold standard method) in 15,917 patients with fasting triglyceride concentrations <400 mg/dl (4.5 mmol/L). Both variation and bias of calculated LDL-C increased at lower values of measured LDL-C. The 95% confidence intervals for a calculated LDL-C of 70 mg/dl (1.8 mmol/L) and 30 mg/dl (0.8 mmol/L) were 60 to 86 mg/dl (1.6 to 2.2 mmol/L) and 24 to 60 mg/dl (0.6 to 1.6 mmol/L), respectively. Previous recommendations have emphasized the requirement for a fasting sample with triglycerides <400 mg/dl (4.5 mmol/L) to calculate LDL-C by the Friedewald equation. However, no recommendations have addressed the appropriate lower reportable limit for calculated LDL-C. In conclusion, calculated LDL-C <30 mg/dl (0.8 mmol/L) should not be reported because of significant deviation from the gold standard measured LDL-C results, and caution is advised when using calculated LDL-CF values <70 mg/dl (1.8 mmol/L) to make treatment decisions.

  20. Power system reliability impacts of wind generation and operational reserve requirements

    E. Gil


    Full Text Available Due to its variability, wind generation integration presents a significant challenge to power system operators in order to maintain adequate reliability levels while ensuring least cost operation. This paper explores the trade-off between the benefits associated to a higher wind penetration and the additional operational reserve requirements that they impose. Such exploration is valued in terms of its effect on power system reliability, measured as an amount of unserved energy. The paper also focuses on how changing the Value of Lost Load (VoLL can be used to attain different reliability targets, and how wind power penetration and the diversity of the wind energy resource will impact quality of supply (in terms of instances of unserved energy. The evaluation of different penetrations of wind power generation, different wind speed profiles, wind resource diversity, and different operational reserve requirements, is conducted on the Chilean Northern Interconnected System (SING using statistical modeling of wind speed time series and computer simulation through a 24-hour ahead unit commitment algorithm and a Monte Carlo simulation scheme. Results for the SING suggest that while wind generation can significantly reduce generation costs, it can also imply higher security costs to reach acceptable reliability levels.

  1. Calculation Method for Reliability of Agricultural Distribution Power Networks while Applying Functions of Boolean Algebra

    V. Rusan


    Full Text Available The paper considers calculation methods for reliability of  agricultural distribution power networks while using Boolean algebra functions and analytical method. Reliability of 10 kV overhead line circuits with automatic sectionalization points and automatic standby activation has been investigated in the paper.

  2. Validating the calculated reliability and availability in Dutch storm surge barriers (and other infrastructural works)

    Kleijn van Willigen, G.K.; Meerveld, H. van


    The reliability and availability of the Dutch storm surge barriers are calculated by probabilistic risk assessment and various underlying risk analysis methods. These calculations, however, focus on the numerical probability of the storm surge barrier functioning adequately, and the implementation o

  3. Constrained Mathematics for Calculating Logical Safety and Reliability Probabilities with Uncertain Inputs

    Cooper, D.K.; Cooper, J.A.; Ferson, S.


    Calculating safety and reliability probabilities with functions of uncertain variables can yield incorrect or misleading results if some precautions are not taken. One important consideration is the application of constrained mathematics for calculating probabilities for functions that contain repeated variables. This paper includes a description of the problem and develops a methodology for obtaining an accurate solution.

  4. Dispatchability Maximization for Co-Optimized Energy and Reserve Dispatch With Explicit Reliability Guarantee

    Wei, Wei; Wang, Jianhui; Mei, Shengwei


    In this paper, we consider dispatchability as the set of all admissible nodal wind power injections that will not cause infeasibility in real-time dispatch (RTD). Our work reveals that the dispatchability of the affine policy based RTD (AF-RTD) is a polytope whose coefficients are linear functions of the generation schedule and the gain matrix of affine policy. Two mathematical formulations of the dispatchability maximized energy and reserve dispatch (DM-ERD) are proposed. The first one maximizes the distance from the forecast to the boundaries of the dispatchability polytope subject to the available production cost or reserve cost. Provided the forecast value and variance of wind power, the generalized Gauss inequality (GGI) is adopted to evaluate the probability of infeasible RTD without the exact probability distribution of wind power. Combining the first formulation and the GGI approach, the second one minimizes the total cost subject to a desired reliability level through dispatchability maximization. Efficient convex optimization based algorithms are developed to solve these two models. Different from the conventional robust optimization method, our model does not rely on the specific uncertainty set of wind generation and directly optimizes the uncertainty accommodation capability of the power system. The proposed method is also compared with the affine policy based robust energy and reserve dispatch (AR-ERD). Case studies on the PJM 5-bus system illustrate the proposed concept and method. Experiments on the IEEE 118-bus system demonstrate the applicability of our method on moderate sized systems and its scalability to large dimensional uncertainty.

  5. Fault Specific Seismic Hazard Maps as Input to Loss Reserves Calculation for Attica Buildings

    Deligiannakis, Georgios; Papanikolaou, Ioannis; Zimbidis, Alexandros; Roberts, Gerald


    Greece is prone to various natural disasters, such as wildfires, floods, landslides and earthquakes, due to the special environmental and geological conditions dominating in tectonic plate boundaries. Seismic is the predominant risk, in terms of damages and casualties in the Greek territory. The historical record of earthquakes in Greece has been published from various researchers, providing useful data in seismic hazard assessment of Greece. However, the completeness of the historical record in Greece, despite being one of the longest worldwide, reaches only 500 years for M ≥ 7.3 and less than 200 years for M ≥ 6.5. Considering that active faults in the area have recurrence intervals of a few hundred to several thousands of years, it is clear that many active faults have not been activated during the completeness period covered by the historical records. New Seismic Hazard Assessment methodologies tend to follow fault specific approaches where seismic sources are geologically constrained active faults, in order to address problems related to the historical records incompleteness, obtain higher spatial resolution and calculate realistic source locality distances, since seismic sources are very accurately located. Fault specific approaches provide quantitative assessments as they measure fault slip rates from geological data, providing a more reliable estimate of seismic hazard. We used a fault specific seismic hazard assessment approach for the region of Attica. The method of seismic hazard mapping from geological fault throw-rate data combined three major factors: Empirical data which combine fault rupture lengths, earthquake magnitudes and coseismic slip relationships. The radiuses of VI, VII, VIII and IX isoseismals on the Modified Mercalli (MM) intensity scale. Attenuation - amplification functions for seismic shaking on bedrock compared to basin filling sediments. We explicitly modeled 22 active faults that could affect the region of Attica, including

  6. Bayesian Algorithms for Calculating Symbolic Rates of the Unreliability and Reliability of the Electric Supply

    Włodzimierz Korniluk


    Full Text Available The report presents the use of Bayesian networks in the calculation of symbolic indicators of reliability and unreliability of the electric power supplying load point. The calculation of indicators of reliability is determined by the analytical dependencies. These dependencies are used to estimate: probability of up or down state of power system components supplying the load point; total probability distribution; conditional probabilities of the state power or lack of power appearance; the intensity of current interruptions and the average time of their duration; contributions of individual power system components in the service reliability. This report describes how to obtain these analytical dependencies, using the ultimate application for symbolic computations Mathematica (ver. 8. In this paper we will discuss the results of the symbolic computations for selected supply power system and methods for reducing the duration of symbolic computations of indicators for multiple-compound electrical power systems.

  7. Reliability of the calculated maximal lactate steady state in amateur cyclists

    Jennifer Adam


    Full Text Available Complex performance diagnostics in sports medicine should contain maximal aerobic and maximal anaerobic performance. The requirements on appropriate stress protocols are high. To validate a test protocol quality criteria like objectivity and reliability are necessary. Therefore, the present study was performed in intention to analyze the reliability of maximal lactate production rate ( VLamax by using a sprint test, maximum oxygen consumption ( VO 2max by using a ramp test and, based on these data, resulting power in calculated maximum lactate-steady-state (PMLSS especially for amateur cyclists. All subjects (n=23, age 26 ± 4 years were leisure cyclists. At three different days they completed first a sprint test to approximate VLamax. After 60 min of recreation time a ramp test to assess VO 2max was performed. The results of VLamax-test and VO 2max -test and the body weight were used to calculate PMLSS for all subjects. The intra class correlation (ICC for VLamax and VO 2max was 0.904 and 0.987, respectively, coefficient of variation (CV was 6.3 % and 2.1 %, respectively. Between the measurements the reliable change index of 0.11 mmol∙l-1∙s-1 for VLamax and 3.3 ml∙kg-1∙min-1 for VO 2max achieved significance. The mean of the calculated PMLSS was 237 ± 72 W with an RCI of 9 W and reached with ICC = 0.985 a very high reliability. Both metabolic performance tests and the calculated PMLSS are reliable for leisure cyclists.

  8. Calculation of Spot Reliability Evaluation Scores (SRED) for DNA Microarray Data.

    Shimokawa, Kazuro; Kodzius, Rimantas; Matsumura, Yonehiro; Hayashizaki, Yoshihide


    INTRODUCTIONIn terms of cost per measurement, the use of DNA microarrays for comprehensive and quantitative expression measurements is vastly superior to other methods such as Northern blotting or quantitative reverse transcriptase polymerase chain reaction (QRT-PCR). However, the output values of DNA microarrays are not always highly reliable or accurate compared with other techniques, and the output data sometimes consist of measurements of relative expression (treated sample vs. untreated) rather than absolute expression values as desired. In effect, some measurements from some laboratories do not represent absolute expression values (such as the number of transcripts) and as such are experimentally deficient. This protocol addresses one problem in some microarray data: the absence of accurate measurements. Spot reliability evaluation score for DNA microarrays (SRED) offers a reliability value for each spot in the microarray. SRED does not require an entire microarray to assess the reliability, but rather analyzes the reliability of individual spots of the microarray. The calculation of a reliability index can be used for different microarray systems, which facilitates the analysis of multiple microarray data sets from different experimental platforms.

  9. Operational Impacts of Operating Reserve Demand Curves on Production Cost and Reliability: Preprint

    Krad, Ibrahim; Ibanez, Eduardo; Ela, Erik; Gao, Wenzhong


    The electric power industry landscape is continually evolving. As emerging technologies such as wind, solar, electric vehicles, and energy storage systems become more cost-effective and present in the system, traditional power system operating strategies will need to be reevaluated. The presence of wind and solar generation (commonly referred to as variable generation) may result in an increase in the variability and uncertainty of the net load profile. One mechanism to mitigate this is to schedule and dispatch additional operating reserves. These operating reserves aim to ensure that there is enough capacity online in the system to account for the increased variability and uncertainty occurring at finer temporal resolutions. A new operating reserve strategy, referred to as flexibility reserve, has been introduced in some regions. A similar implementation is explored in this paper, and its implications on power system operations are analyzed.

  10. Operational Impacts of Operating Reserve Demand Curves on Production Cost and Reliability

    Krad, Ibrahim; Ibanez, Eduardo; Ela, Erik; Gao, Wenzhong


    The electric power industry landscape is continually evolving. As emerging technologies such as wind, solar, electric vehicles, and energy storage systems become more cost-effective and present in the system, traditional power system operating strategies will need to be reevaluated. The presence of wind and solar generation (commonly referred to as variable generation) may result in an increase in the variability and uncertainty of the net load profile. One mechanism to mitigate this is to schedule and dispatch additional operating reserves. These operating reserves aim to ensure that there is enough capacity online in the system to account for the increased variability and uncertainty occurring at finer temporal resolutions. A new operating reserve strategy, referred to as flexibility reserve, has been introduced in some regions. A similar implementation is explored in this paper, and its implications on power system operations are analyzed.

  11. Operational Impacts of Operating Reserve Demand Curves on Production Cost and Reliability: Preprint

    Krad, Ibrahim; Ibanez, Eduardo; Ela, Erik; Gao, Wenzhong


    The electric power industry landscape is continually evolving. As emerging technologies such as wind, solar, electric vehicles, and energy storage systems become more cost-effective and present in the system, traditional power system operating strategies will need to be reevaluated. The presence of wind and solar generation (commonly referred to as variable generation) may result in an increase in the variability and uncertainty of the net load profile. One mechanism to mitigate this is to schedule and dispatch additional operating reserves. These operating reserves aim to ensure that there is enough capacity online in the system to account for the increased variability and uncertainty occurring at finer temporal resolutions. A new operating reserve strategy, referred to as flexibility reserve, has been introduced in some regions. A similar implementation is explored in this paper, and its implications on power system operations are analyzed.

  12. A model for reliability analysis and calculation applied in an example from chemical industry

    Pejović Branko B.


    Full Text Available The subject of the paper is reliability design in polymerization processes that occur in reactors of a chemical industry. The designed model is used to determine the characteristics and indicators of reliability, which enabled the determination of basic factors that result in a poor development of a process. This would reduce the anticipated losses through the ability to control them, as well as enabling the improvement of the quality of production, which is the major goal of the paper. The reliability analysis and calculation uses the deductive method based on designing of a scheme for fault tree analysis of a system based on inductive conclusions. It involves the use standard logical symbols and rules of Boolean algebra and mathematical logic. The paper eventually gives the results of the work in the form of quantitative and qualitative reliability analysis of the observed process, which served to obtain complete information on the probability of top event in the process, as well as objective decision making and alternative solutions.

  13. 78 FR 71448 - Regional Reliability Standard BAL-002-WECC-2-Contingency Reserve


    ... demand-side management as a resource; and (5) miscellaneous directives.\\14\\ \\13\\ Version One Regional.... Demand-Side Management as a Resource 15. The Commission determined that remanded regional Reliability Standard BAL-002-WECC-1 did not allow demand-side management that is technically capable of providing...

  14. Improved reliability, accuracy and quality in automated NMR structure calculation with ARIA

    Mareuil, Fabien [Institut Pasteur, Cellule d' Informatique pour la Biologie (France); Malliavin, Thérèse E.; Nilges, Michael; Bardiaux, Benjamin, E-mail: [Institut Pasteur, Unité de Bioinformatique Structurale, CNRS UMR 3528 (France)


    In biological NMR, assignment of NOE cross-peaks and calculation of atomic conformations are critical steps in the determination of reliable high-resolution structures. ARIA is an automated approach that performs NOE assignment and structure calculation in a concomitant manner in an iterative procedure. The log-harmonic shape for distance restraint potential and the Bayesian weighting of distance restraints, recently introduced in ARIA, were shown to significantly improve the quality and the accuracy of determined structures. In this paper, we propose two modifications of the ARIA protocol: (1) the softening of the force field together with adapted hydrogen radii, which is meaningful in the context of the log-harmonic potential with Bayesian weighting, (2) a procedure that automatically adjusts the violation tolerance used in the selection of active restraints, based on the fitting of the structure to the input data sets. The new ARIA protocols were fine-tuned on a set of eight protein targets from the CASD–NMR initiative. As a result, the convergence problems previously observed for some targets was resolved and the obtained structures exhibited better quality. In addition, the new ARIA protocols were applied for the structure calculation of ten new CASD–NMR targets in a blind fashion, i.e. without knowing the actual solution. Even though optimisation of parameters and pre-filtering of unrefined NOE peak lists were necessary for half of the targets, ARIA consistently and reliably determined very precise and highly accurate structures for all cases. In the context of integrative structural biology, an increasing number of experimental methods are used that produce distance data for the determination of 3D structures of macromolecules, stressing the importance of methods that successfully make use of ambiguous and noisy distance data.

  15. Calculation Method of Single Well Controlled Reserves Using Data of Production Trends

    Tan Xianhong


    @@ Single well controlled reserves of offshore oilfields are very large.Sometimes one or two wells are adopted for the development control of the reserves of a certain block.It is of great significance for directing the oilfield adjustment work to know the actual conditions of the single well controlled reserves.Generally, the single well controlled reserves of a well are determined by such methods as volumetric method, well test method and numerical simulation method.

  16. Environmental flow calculation for the maintenance of the water reserve of the Piaxtla River, Sinaloa, Mexico

    Guadalupe de la Lanza Espino


    status to be achieved within the watershed to maintain the integrity of existing ecosystems or when they believe that they are degraded, contributing to the recovery or rehabilitation; and annual percentage rate recommended for environmental protection. Based on this, the purpose of this study was to quantify the river flow of the Piaxtla river, in the state of Sinaloa. The river runoff data bases for 36 and nine years were compared, showed differences mainly between the frequency of maximum runoff and its origin, and indicated that it is advisable to use a data base of more than 20 years. However, results were similar in the final calculation of the environmental or ecological river flows; that is to say, total runoff volume was 62.1% considering 36 years and 57.7% for nine years of information. We conclude that the ecological importance of Piaxtla river was very high and the use of water pressure was low (considering that database runoff only included until 1999 and did not take into account population growth and activities. To determine the final volume reserved for the environment or ecological flow, could be estimated not only with a database of 36 years, but for nine years also confirming that those rivers that have databases of 10 years can the methodology used hydrological indicated by the NMX said. Particularly in this study it was determined that for parameters more detailed as the volume of the base rate of the annual volume, according to the frequency of occurrence, both very dry years, dry, average and wet, and influence of meteorological events that determine periods separate return, it is advisable to use minimum data bases as brand NMX 20 years.

  17. Reliable method for calculating the center of rotation in parallel-beam tomography.

    Vo, Nghia T; Drakopoulos, Michael; Atwood, Robert C; Reinhard, Christina


    High-throughput processing of parallel-beam X-ray tomography at synchrotron facilities is lacking a reliable and robust method to determine the center of rotation in an automated fashion, i.e. without the need for a human scorer. Well-known techniques based on center of mass calculation, image registration, or reconstruction evaluation work well under favourable conditions but they fail in cases where samples are larger than field of view, when the projections show low signal-to-noise, or when optical defects dominate the contrast. Here we propose an alternative technique which is based on the Fourier analysis of the sinogram. Our technique shows excellent performance particularly on challenging data.

  18. Accurate, robust, and reliable calculations of Poisson-Boltzmann binding energies.

    Nguyen, Duc D; Wang, Bao; Wei, Guo-Wei


    Poisson-Boltzmann (PB) model is one of the most popular implicit solvent models in biophysical modeling and computation. The ability of providing accurate and reliable PB estimation of electrostatic solvation free energy, ΔGel, and binding free energy, ΔΔGel, is important to computational biophysics and biochemistry. In this work, we investigate the grid dependence of our PB solver (MIBPB) with solvent excluded surfaces for estimating both electrostatic solvation free energies and electrostatic binding free energies. It is found that the relative absolute error of ΔGel obtained at the grid spacing of 1.0 Å compared to ΔGel at 0.2 Å averaged over 153 molecules is less than 0.2%. Our results indicate that the use of grid spacing 0.6 Å ensures accuracy and reliability in ΔΔGel calculation. In fact, the grid spacing of 1.1 Å appears to deliver adequate accuracy for high throughput screening. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  19. Improved Accuracy of the Inherent Shrinkage Method for Fast and More Reliable Welding Distortion Calculations

    Mendizabal, A.; González-Díaz, J. B.; San Sebastián, M.; Echeverría, A.


    This paper describes the implementation of a simple strategy adopted for the inherent shrinkage method (ISM) to predict welding-induced distortion. This strategy not only makes it possible for the ISM to reach accuracy levels similar to the detailed transient analysis method (considered the most reliable technique for calculating welding distortion) but also significantly reduces the time required for these types of calculations. This strategy is based on the sequential activation of welding blocks to account for welding direction and transient movement of the heat source. As a result, a significant improvement in distortion prediction is achieved. This is demonstrated by experimentally measuring and numerically analyzing distortions in two case studies: a vane segment subassembly of an aero-engine, represented with 3D-solid elements, and a car body component, represented with 3D-shell elements. The proposed strategy proves to be a good alternative for quickly estimating the correct behaviors of large welded components and may have important practical applications in the manufacturing industry.

  20. Combining of different data pools for calculating a reliable POD for real defects

    Kanzler, Daniel; Müller, Christina; Pitkänen, Jorma


    Real defects are essential for the evaluation of the reliability of non destructive testing (NDT) methods, especially in relation to the integrity of components. But in most of the cases the amount of available real defects is not sufficient to evaluate the system. Model-assisted and transfer functions are one way to handle that challenge. This study is focused on a combination of different data pools to create a sufficient amount of data for the reliability estimation. A widespread approach for calculating the Probability of Detection (POD) was used on a radiographic testing (RT) method. The highest contrast to noise ratio (CNR) of each indication is usually selected as the signal in the "â vs. a" (signal-response) approach for RT. By combining real and artificial defects (flat bottom holes, side drill holes, flat bottom squares, notches, etc) in RT the highest signals are close to each other, but the process of creating and evaluating real defects is much more complex. The solution is seen in the combination of real and artificial data using a weighted least square approach. The weights for real or artificial data were based on the importance, the value and the different detection behavior of the different data. For comparison, the alternative combination through the Bayesian Updating was also applied. As verification, a data pool with a large amount of real data was available. In an advanced approach for evaluating the digital RT data, the size of the indication (perpendicular to the X-ray beam) was introduced as additional information. The signal now consists of the CNR and the area of the indication. The detectability is changing depending on the area of the indication, a fact that was ignored in the previous POD calculations for RT. This points out that a weighted least square approach to pool the data might no longer be adequate. The Bayesian Updating of the estimated parameters of the relationship between the signal field (the area of the indication) and

  1. Combining of different data pools for calculating a reliable POD for real defects

    Kanzler, Daniel, E-mail:, E-mail:; Müller, Christina, E-mail:, E-mail: [Federal Institute for Materials Testing and Research, Berlin (Germany); Pitkänen, Jorma, E-mail: [Posiva Oy, Eurajoki (Finland)


    Real defects are essential for the evaluation of the reliability of non destructive testing (NDT) methods, especially in relation to the integrity of components. But in most of the cases the amount of available real defects is not sufficient to evaluate the system. Model-assisted and transfer functions are one way to handle that challenge. This study is focused on a combination of different data pools to create a sufficient amount of data for the reliability estimation. A widespread approach for calculating the Probability of Detection (POD) was used on a radiographic testing (RT) method. The highest contrast to noise ratio (CNR) of each indication is usually selected as the signal in the 'â vs. a' (signal-response) approach for RT. By combining real and artificial defects (flat bottom holes, side drill holes, flat bottom squares, notches, etc) in RT the highest signals are close to each other, but the process of creating and evaluating real defects is much more complex. The solution is seen in the combination of real and artificial data using a weighted least square approach. The weights for real or artificial data were based on the importance, the value and the different detection behavior of the different data. For comparison, the alternative combination through the Bayesian Updating was also applied. As verification, a data pool with a large amount of real data was available. In an advanced approach for evaluating the digital RT data, the size of the indication (perpendicular to the X-ray beam) was introduced as additional information. The signal now consists of the CNR and the area of the indication. The detectability is changing depending on the area of the indication, a fact that was ignored in the previous POD calculations for RT. This points out that a weighted least square approach to pool the data might no longer be adequate. The Bayesian Updating of the estimated parameters of the relationship between the signal field (the area of the

  2. 26 CFR 1.409A-4 - Calculation of income inclusion. [Reserved


    ... 26 Internal Revenue 5 2010-04-01 2010-04-01 false Calculation of income inclusion. 1.409A-4 Section 1.409A-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME... of income inclusion. ...

  3. Local probabilistic sensitivity measures for comparing FORM and Monte Carlo calculations illustrated with dike ring reliability calculations

    Cooke, Roger M.; van Noortwijk, Jan M.


    We define local probabilistic sensitivity measures as proportional to ∂E( X i| Z = z)/ ∂z, where Z is a function of random variables XI,…, X n. These measures are local in that they depend only on the neighborhood of Z = z, but unlike other local sensitivity measures, the local probabilistic sensitivity of X i does not depend on values of other input variables. For the independent linear normal model, or indeed for any model for which X i has linear regression on Z, the above measure equals σx iρ ( Z,X i)/ σz. When linear regression does not hold, the new sensitivity measures can be compared with the correlation coefficients to indicate degree of departure from linearity. We say that Z is probabilistically dissonant in X i at Z = z if Z is increasing (decreasing) in X i at z, but probabilistically decreasing (increasing) at z. Probabilistic dissonance is rather common in complicated models. The new measures are able to pick up this probabilistic dissonance. These notions are illustrated with data from an ongoing uncertainty analysis of dike ring reliability.

  4. 75 FR 43059 - Mandatory Reliability Standards for the Calculation of Available Transfer Capability, Capacity...


    ...-Power System; and Standards for Business Practices and Communications Protocols for Public Utilities..., Order No. 729-A, 131 FERC ] 61,109 (2010). \\2\\ Standards for Business Practices and Communication... of Available Transfer Capability, Capacity Benefit Margins, Transmission Reliability Margins,...

  5. Mine Reserves Calculation Based on Minex%基于Minex的矿山储量计算



    The calculation of the coal and rock amount is an important basis for compiling mine engineering schedule plan of the open pit, which is the most important work in mining design. Taking Heishan open pit of Xinjiang Houxia coalfield as an example, this paper established the stope model of the first mining area, determined the coal and rock amount in various engineering positions and drew the V - P curve by using Minex 6.0 software, which provided an important basis for mining designers to compile the mining schedule plan and select equipment and mining technology.%煤岩量的计算是露天矿编制矿山工程进度计划的重要依据,是采矿设计中最主要的工作。利用Minex6.0软件,以新疆后峡煤田黑山露天煤矿为例,建立了首采区的采场模型,确定各个工程位置的煤岩量并绘制V—P曲线,为采矿设计人员编制开采进度计划及开采工艺和设备的选择提供了重要的依据,大大提高了采矿设计人员的工作效率。

  6. Inter-rater reliability of h-index scores calculated by Web of Science and Scopus for clinical epidemiology scientists.

    Walker, Benjamin; Alavifard, Sepand; Roberts, Surain; Lanes, Andrea; Ramsay, Tim; Boet, Sylvain


    We investigated the inter-rater reliability of Web of Science (WoS) and Scopus when calculating the h-index of 25 senior scientists in the Clinical Epidemiology Program of the Ottawa Hospital Research Institute. Bibliometric information and the h-indices for the subjects were computed by four raters using the automatic calculators in WoS and Scopus. Correlation and agreement between ratings was assessed using Spearman's correlation coefficient and a Bland-Altman plot, respectively. Data could not be gathered from Google Scholar due to feasibility constraints. The Spearman's rank correlation between the h-index of scientists calculated with WoS was 0.81 (95% CI 0.72-0.92) and with Scopus was 0.95 (95% CI 0.92-0.99). The Bland-Altman plot showed no significant rater bias in WoS and Scopus; however, the agreement between ratings is higher in Scopus compared to WoS. Our results showed a stronger relationship and increased agreement between raters when calculating the h-index of a scientist using Scopus compared to WoS. The higher inter-rater reliability and simple user interface used in Scopus may render it the more effective database when calculating the h-index of senior scientists in epidemiology. © 2016 Health Libraries Group.

  7. The case for using the repeatability coefficient when calculating test-retest reliability.

    Sharmila Vaz

    Full Text Available The use of standardised tools is an essential component of evidence-based practice. Reliance on standardised tools places demands on clinicians to understand their properties, strengths, and weaknesses, in order to interpret results and make clinical decisions. This paper makes a case for clinicians to consider measurement error (ME indices Coefficient of Repeatability (CR or the Smallest Real Difference (SRD over relative reliability coefficients like the Pearson's (r and the Intraclass Correlation Coefficient (ICC, while selecting tools to measure change and inferring change as true. The authors present statistical methods that are part of the current approach to evaluate test-retest reliability of assessment tools and outcome measurements. Selected examples from a previous test-retest study are used to elucidate the added advantages of knowledge of the ME of an assessment tool in clinical decision making. The CR is computed in the same units as the assessment tool and sets the boundary of the minimal detectable true change that can be measured by the tool.

  8. Reliability Analysis-Based Numerical Calculation of Metal Structure of Bridge Crane

    Wenjun Meng


    Full Text Available The study introduced a finite element model of DQ75t-28m bridge crane metal structure and made finite element static analysis to obtain the stress response of the dangerous point of metal structure in the most extreme condition. The simulated samples of the random variable and the stress of the dangerous point were successfully obtained through the orthogonal design. Then, we utilized BP neural network nonlinear mapping function trains to get the explicit expression of stress in response to the random variable. Combined with random perturbation theory and first-order second-moment (FOSM method, the study analyzed the reliability and its sensitivity of metal structure. In conclusion, we established a novel method for accurately quantitative analysis and design of bridge crane metal structure.

  9. Accurate, robust and reliable calculations of Poisson-Boltzmann solvation energies

    Wang, Bao


    Developing accurate solvers for the Poisson Boltzmann (PB) model is the first step to make the PB model suitable for implicit solvent simulation. Reducing the grid size influence on the performance of the solver benefits to increasing the speed of solver and providing accurate electrostatics analysis for solvated molecules. In this work, we explore the accurate coarse grid PB solver based on the Green's function treatment of the singular charges, matched interface and boundary (MIB) method for treating the geometric singularities, and posterior electrostatic potential field extension for calculating the reaction field energy. We made our previous PB software, MIBPB, robust and provides almost grid size independent reaction field energy calculation. Large amount of the numerical tests verify the grid size independence merit of the MIBPB software. The advantage of MIBPB software directly make the acceleration of the PB solver from the numerical algorithm instead of utilization of advanced computer architectures...

  10. Transient integral boundary layer method to calculate the translesional pressure drop and the fractional flow reserve in myocardial bridges

    Möhlenkamp Stefan


    Full Text Available Abstract Background The pressure drop – flow relations in myocardial bridges and the assessment of vascular heart disease via fractional flow reserve (FFR have motivated many researchers the last decades. The aim of this study is to simulate several clinical conditions present in myocardial bridges to determine the flow reserve and consequently the clinical relevance of the disease. From a fluid mechanical point of view the pathophysiological situation in myocardial bridges involves fluid flow in a time dependent flow geometry, caused by contracting cardiac muscles overlying an intramural segment of the coronary artery. These flows mostly involve flow separation and secondary motions, which are difficult to calculate and analyse. Methods Because a three dimensional simulation of the haemodynamic conditions in myocardial bridges in a network of coronary arteries is time-consuming, we present a boundary layer model for the calculation of the pressure drop and flow separation. The approach is based on the assumption that the flow can be sufficiently well described by the interaction of an inviscid core and a viscous boundary layer. Under the assumption that the idealised flow through a constriction is given by near-equilibrium velocity profiles of the Falkner-Skan-Cooke (FSC family, the evolution of the boundary layer is obtained by the simultaneous solution of the Falkner-Skan equation and the transient von-Kármán integral momentum equation. Results The model was used to investigate the relative importance of several physical parameters present in myocardial bridges. Results have been obtained for steady and unsteady flow through vessels with 0 – 85% diameter stenosis. We compare two clinical relevant cases of a myocardial bridge in the middle segment of the left anterior descending coronary artery (LAD. The pressure derived FFR of fixed and dynamic lesions has shown that the flow is less affected in the dynamic case, because the distal

  11. Reliable calculation in probabilistic logic: Accounting for small sample size and model uncertainty

    Ferson, S. [Applied Biomathematics, Setauket, NY (United States)


    A variety of practical computational problems arise in risk and safety assessments, forensic statistics and decision analyses in which the probability of some event or proposition E is to be estimated from the probabilities of a finite list of related subevents or propositions F,G,H,.... In practice, the analyst`s knowledge may be incomplete in two ways. First, the probabilities of the subevents may be imprecisely known from statistical estimations, perhaps based on very small sample sizes. Second, relationships among the subevents may be known imprecisely. For instance, there may be only limited information about their stochastic dependencies. Representing probability estimates as interval ranges on has been suggested as a way to address the first source of imprecision. A suite of AND, OR and NOT operators defined with reference to the classical Frochet inequalities permit these probability intervals to be used in calculations that address the second source of imprecision, in many cases, in a best possible way. Using statistical confidence intervals as inputs unravels the closure properties of this approach however, requiring that probability estimates be characterized by a nested stack of intervals for all possible levels of statistical confidence, from a point estimate (0% confidence) to the entire unit interval (100% confidence). The corresponding logical operations implied by convolutive application of the logical operators for every possible pair of confidence intervals reduces by symmetry to a manageably simple level-wise iteration. The resulting calculus can be implemented in software that allows users to compute comprehensive and often level-wise best possible bounds on probabilities for logical functions of events.

  12. The extent of food waste generation across EU-27: different calculation methods and the reliability of their results.

    Bräutigam, Klaus-Rainer; Jörissen, Juliane; Priefer, Carmen


    The reduction of food waste is seen as an important societal issue with considerable ethical, ecological and economic implications. The European Commission aims at cutting down food waste to one-half by 2020. However, implementing effective prevention measures requires knowledge of the reasons and the scale of food waste generation along the food supply chain. The available data basis for Europe is very heterogeneous and doubts about its reliability are legitimate. This mini-review gives an overview of available data on food waste generation in EU-27 and discusses their reliability against the results of own model calculations. These calculations are based on a methodology developed on behalf of the Food and Agriculture Organization of the United Nations and provide data on food waste generation for each of the EU-27 member states, broken down to the individual stages of the food chain and differentiated by product groups. The analysis shows that the results differ significantly, depending on the data sources chosen and the assumptions made. Further research is much needed in order to improve the data stock, which builds the basis for the monitoring and management of food waste.

  13. Assessment of the reliability of calculations of the coefficient of variation for normal and polymegethous human corneal endothelium.

    Doughty, M J; Fonn, D; Trang Nguyen, K


    In endothelial morphometry, uncertainty exists concerning how many cells should be measured. A study was undertaken to calculate mean cell area and coefficient of variation (COV) of cell areas using different numbers of cells from photo-slitlamp pictures and published micrographs. Groups of 65, 95, or 165 tesselated cells were measured and area and COV values calculated in progressive sets of 5 cells; each pair of values was compared to that obtained using all cells in each group. The results show that, for both normal (homomegethous) and irregular (polymegethous) endothelia, even cell counts as low as 50 cells can usually provide average cell area values that are within 1 to 2% of the values estimated from larger groups of cells. A similar reliability was observed for estimates of COV for normal endothelia. However, for polymegethous endothelia, even with 100 cells analyzed, the estimates of COV generally only approached a +/- 4% reliability. This uncertainty in COV estimates should be considered in both comparative studies and in regression analyses of COV changes over time or other variables.

  14. Development of Energy and Reserve Pre-dispatch and Re-dispatch Models for Real-time Price Risk and Reliability Assessment

    Ding, Yi; Xie, Min; Wu, Qiuwei


    of securing proper balancing between generation and demand. The high penetration of renewable energy sources will also increase the burden of system operator for maintaining system reliabilities. However the current strategy of reliability management developed for conventional power systems and existing...... electricity market design may not cope with the future challenges the power system faces. The development of smart grid will enable power system scheduling and the electricity market to operate in a shorter time horizon for better integrating renewable energy sources into power systems. This paper presents...... the real time operation, the energy re-dispatch model is used for contingency management and providing balancing services based on the results of the energy and reserve pre-dispatch model. The energy re-dispatch model is formulated as a single-period AC OPF model, which is used to determine generation re...

  15. Reliability of calculation of the lithosphere deformations in tectonically stable area of Poland based on the GPS measurements

    Araszkiewicz, Andrzej; Jarosiński, Marek


    In this research we aimed to check if the GPS observations can be used for calculation of a reliable deformation pattern of the intracontinental lithosphere in seismically inactive areas, such as territory of Poland. For this purpose we have used data mainly from the ASG-EUPOS permanent network and the solutions developed by the MUT CAG team (Military University of Technology: Centre of Applied Geomatics). From the 128 analyzed stations almost 100 are mounted on buildings. Daily observations were processed in the Bernese 5.0 software and next the weekly solutions were used to determine the station velocities expressed in ETRF2000. The strain rates were determined for almost 200 triangles with GPS stations in their corners plotted used Delaunay triangulation. The obtained scattered directions of deformations and highly changeable values of strain rates point to insufficient antennas' stabilization as for geodynamical studies. In order to depict badly stabilized stations we carried out a benchmark test to show what might be the effect of one station drift on deformations in contacting triangles. Based on the benchmark results, from our network we have eliminated the stations which showed deformation pattern characteristic for instable station. After several rounds of strain rate calculations and eliminations of dubious points we have reduced the number of stations down to 60. The refined network revealed more consistent deformation pattern across Poland. Deformations compared with the recent stress field of the study area disclosed good correlation in some places and significant discrepancies in the others, which will be the subject of future research.

  16. A Reliability Calculation Method for Web Service Composition Using Fuzzy Reasoning Colored Petri Nets and Its Application on Supercomputing Cloud Platform

    Ziyun Deng


    Full Text Available In order to develop a Supercomputing Cloud Platform (SCP prototype system using Service-Oriented Architecture (SOA and Petri nets, we researched some technologies for Web service composition. Specifically, in this paper, we propose a reliability calculation method for Web service compositions, which uses Fuzzy Reasoning Colored Petri Net (FRCPN to verify the Web service compositions. We put forward a definition of semantic threshold similarity for Web services and a formal definition of FRCPN. We analyzed five kinds of production rules in FRCPN, and applied our method to the SCP prototype. We obtained the reliability value of the end Web service as an indicator of the overall reliability of the FRCPN. The method can test the activity of FRCPN. Experimental results show that the reliability of the Web service composition has a correlation with the number of Web services and the range of reliability transition values.

  17. Establishing the definition and inter-rater reliability of cortical silent period calculation in subjects with focal hand dystonia and healthy controls.

    Kimberley, Teresa Jacobson; Borich, Michael R; Prochaska, Kristina D; Mundfrom, Shannon L; Perkins, Ariel E; Poepping, Joseph M


    The purpose of this paper is to describe a clearly defined manual method for calculating cortical silent period (CSP) length that can be employed successfully and reliably by raters after minimal training in subjects with focal hand dystonia (FHD) and healthy subjects. A secondary purpose was to explore intra-subject variability of the CSP in subjects with FHD vs. healthy subjects. Two raters previously naïve to CSP identification and one experienced rater independently analyzed 170 CSP measurements collected in 6 subjects with focal hand dystonia (FHD) and 9 healthy subjects. Intraclass correlation coefficient (ICC) was calculated to quantify inter-rater reliability within the two groups of subjects. The relative variability of CSP in each group was calculated by the coefficient of variation (CV). Relative variation between raters within repeated measures of individual subjects was also quantified by CV. Reliability measures were as follows-mean of three raters: all subjects: ICC=0.976; within healthy subjects: ICC=0.965; in subjects with FHD: ICC=0.956. The median within-subject variability for the healthy group was CV=7.33% and in subjects with FHD:CV=11.78%. The median variability of calculating individual subject CSP duration between raters was CV=10.23% in subjects with dystonia and CV=10.46% in healthy subjects. Manual calculation of CSP results in excellent reliability between raters of varied levels of experience. Healthy subjects display less variability in CSP. Despite greater variability, the CSP in impaired subjects can be reliably calculated across raters.

  18. Reliable Real-time Calculation of Heart-rate Complexity in Critically Ill Patients Using Multiple Noisy Waveform Sources


    related metrics for detecting sepsis and multior- gan failure, improvement of HRC calculations may help detect significant changes from baseline values...calculations. Equiva- lence tests between mean HRC values derived from man- ually verified sequences and those derived from automatically detected peaks...assessment of HRC in critically ill patients. Keywords Signal detection analysis Electrocardiography Heart rate Clinical decision support

  19. Estimating the accuracy of a reduced-order model for the calculation of fractional flow reserve (FFR).

    Boileau, Etienne; Pant, Sanjay; Roobottom, Carl; Sazonov, Igor; Deng, Jingjing; Xie, Xianghua; Nithiarasu, Perumal


    Image-based noninvasive fractional flow reserve (FFR) is an emergent approach to determine the functional relevance of coronary stenoses. The present work aimed to determine the feasibility of using a method based on coronary computed tomography angiography (CCTA) and reduced-order models (0D-1D) for the evaluation of coronary stenoses. The reduced-order methodology (cFFRRO ) was kept as simple as possible and did not include pressure drop or stenosis models. The geometry definition was incorporated into the physical model used to solve coronary flow and pressure. cFFRRO was assessed on a virtual cohort of 30 coronary artery stenoses in 25 vessels and compared with a standard approach based on 3D computational fluid dynamics (cFFR3D ). In this proof-of-concept study, we sought to investigate the influence of geometry and boundary conditions on the agreement between both methods. Performance on a per-vessel level showed a good correlation between both methods (Pearson's product-moment R=0.885, P<0.01), when using cFFR3D  as the reference standard. The 95% limits of agreement were -0.116 and 0.08, and the mean bias was -0.018 (SD =0.05). Our results suggest no appreciable difference between cFFRRO  and cFFR3D with respect to lesion length and/or aspect ratio. At a fixed aspect ratio, however, stenosis severity and shape appeared to be the most critical factors accounting for differences in both methods. Despite the assumptions inherent to the 1D formulation, asymmetry did not seem to affect the agreement. The choice of boundary conditions is critical in obtaining a functionally significant drop in pressure. Our initial data suggest that this approach may be part of a broader risk assessment strategy aimed at increasing the diagnostic yield of cardiac catheterisation for in-hospital evaluation of haemodynamically significant stenoses. Copyright © 2017 John Wiley & Sons, Ltd.

  20. Ship Electric Propulsion Simulation System Reliability Evaluation Based on Improved D-S Expert Weight Calculation Method

    Bing Li


    Full Text Available In order to have a better evaluation process to determine the experts weight in the evaluation process, this paper proposes a new expert weight calculation method. First of all to establish electric propulsion simulation evaluation system, use AHP method to calculate the initial weight principle of index. Then use the D-S to fuse the experts evaluation information, combined with the weight vector, structure of the expert weight objective function, and through the genetic algorithm to solve the expert weight size. According to the expert weight vector, calculate the final weight vector. Not only can it greatly make use of the experts information and analyze the similarity of information effectively but also it calculates the weight of each expert objectively. At the same time the evaluation subjective factors have been reduced by the adoption of this new method.

  1. Absolute reliability of hamstring to quadriceps strength imbalance ratios calculated using peak torque, joint angle-specific torque and joint ROM-specific torque values.

    Ayala, F; De Ste Croix, M; Sainz de Baranda, P; Santonja, F


    The main purpose of this study was to determine the absolute reliability of conventional (H/Q(CONV)) and functional (H/Q(FUNC)) hamstring to quadriceps strength imbalance ratios calculated using peak torque values, 3 different joint angle-specific torque values (10°, 20° and 30° of knee flexion) and 4 different joint ROM-specific average torque values (0-10°, 11-20°, 21-30° and 0-30° of knee flexion) adopting a prone position in recreational athletes. A total of 50 recreational athletes completed the study. H/Q(CONV) and H/Q(FUNC) ratios were recorded at 3 different angular velocities (60, 180 and 240°/s) on 3 different occasions with a 72-96 h rest interval between consecutive testing sessions. Absolute reliability was examined through typical percentage error (CVTE), percentage change in the mean (CM) and intraclass correlations (ICC) as well as their respective confidence limits. H/Q(CONV) and H/Q(FUNC) ratios calculated using peak torque values showed moderate reliability values, with CM scores lower than 2.5%, CV(TE) values ranging from 16 to 20% and ICC values ranging from 0.3 to 0.7. However, poor absolute reliability scores were shown for H/Q(CONV) and H/Q(FUNC) ratios calculated using joint angle-specific torque values and joint ROM-specific average torque values, especially for H/Q(FUNC) ratios (CM: 1-23%; CV(TE): 22-94%; ICC: 0.1-0.7). Therefore, the present study suggests that the CV(TE) values reported for H/Q(CONV) and H/Q(FUNC) (≈18%) calculated using peak torque values may be sensitive enough to detect large changes usually observed after rehabilitation programmes but not acceptable to examine the effect of preventitive training programmes in healthy individuals. The clinical reliability of hamstring to quadriceps strength ratios calculated using joint angle-specific torque values and joint ROM-specific average torque values are questioned and should be re-evaluated in future research studies.

  2. Calculation of mean outcrossing rates of non-Gaussian processes with stochastic input parameters - Reliability of containers stowed on ships in severe sea

    Nielsen, Ulrik Dam


    Mean outcrossing rates can be used as a basis for decision support for ships in severe sea. The article describes a procedure for calculating the mean outcrossing rate of non-Gaussian processes with stochastic input parameters. The procedure is based on the first-order reliability method (FORM......) and stochastic parameters are incorporated by carrying out a number of FORM calculations corresponding to combinations of specific values of the stochastic parameters. Subsequently, the individual FORM calculation is weighted according to the joint probability with which the specific combination of parameter....... The results of the procedure are compared with brute force simulations obtained by Monte Carlo simulation (MCS) and good agreement is observed. Importantly, the procedure requires significantly less CPU time compared to MCS to produce mean outcrossing rates....

  3. Reliability assessment of high energy particle induced radioactivity calculation code DCHAIN-SP 2001 by analysis of integral activation experiments with 14 MeV neutrons

    Kai, Tetsuya; Maekawa, Fujio; Kasugai, Yoshimi; Takada, Hiroshi; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kosako, Kazuaki [Sumitomo Atomic Energy Industries, Ltd., Tokyo (Japan)


    Reliability assessment for the high energy particle induced radioactivity calculation code DCHAIN-SP 2001 was carried out through analysis of integral activation experiments with 14-MeV neutrons aiming at validating the cross section and decay data revised from previous version. The following three kinds of experiments conducted at the D-T neutron source facility, FNS, in JAERI were employed: (1) the decay gamma-ray measurement experiment for fusion reactor materials, (2) the decay heat measurement experiment for 32 fusion reactor materials, and (3) the integral activation experiment on mercury. It was found that the calculations with DCHAIN-SP 2001 predicted the experimental data for (1) - (3) within several tens of percent. It was concluded that the cross section data below 20 MeV and the associated decay data as well as the calculation algorithm for solving the Beteman equation that was the master equation of DCHAIN-SP were adequate. (author)

  4. CNDOL: A fast and reliable method for the calculation of electronic properties of very large systems. Applications to retinal binding pocket in rhodopsin and gas phase porphine.

    Montero-Cabrera, Luis Alberto; Röhrig, Ute; Padrón-Garcia, Juan A; Crespo-Otero, Rachel; Montero-Alejo, Ana L; Garcia de la Vega, José M; Chergui, Majed; Rothlisberger, Ursula


    Very large molecular systems can be calculated with the so called CNDOL approximate Hamiltonians that have been developed by avoiding oversimplifications and only using a priori parameters and formulas from the simpler NDO methods. A new diagonal monoelectronic term named CNDOL/21 shows great consistency and easier SCF convergence when used together with an appropriate function for charge repulsion energies that is derived from traditional formulas. It is possible to obtain a priori molecular orbitals and electron excitation properties after the configuration interaction of single excited determinants with reliability, maintaining interpretative possibilities even being a simplified Hamiltonian. Tests with some unequivocal gas phase maxima of simple molecules (benzene, furfural, acetaldehyde, hexyl alcohol, methyl amine, 2,5 dimethyl 2,4 hexadiene, and ethyl sulfide) ratify the general quality of this approach in comparison with other methods. The calculation of large systems as porphine in gas phase and a model of the complete retinal binding pocket in rhodopsin with 622 basis functions on 280 atoms at the quantum mechanical level show reliability leading to a resulting first allowed transition in 483 nm, very similar to the known experimental value of 500 nm of "dark state." In this very important case, our model gives a central role in this excitation to a charge transfer from the neighboring Glu(-) counterion to the retinaldehyde polyene chain. Tests with gas phase maxima of some important molecules corroborate the reliability of CNDOL/2 Hamiltonians.

  5. 机械结构可靠性计算方法%Research on the improved calculation method for mechanical structural reliability

    李四超; 张代国; 张强


    The calculation method for mechanical structural reliability was studied. Based on strainstrength model, the decision method of strength and strain was put forward. Aiming at the existing limitations in the traditional model, an improved calculation method was studied. This improved method widens the application range of traditional strain-strength further.%对机械结构可靠性的计算方法进行了研究,在建立起应力-强度干涉模型的基础上,提出了强度和应力的一般确定方法.同时针对传统应力-强度干涉模型中存在的局限,提出了一种改进方法,进一步拓宽了应力-强度干涉模型的应用范围.

  6. Computer-assisted radiographic calculation of spinal curvature in brachycephalic "screw-tailed" dog breeds with congenital thoracic vertebral malformations: reliability and clinical evaluation.

    Guevar, Julien; Penderis, Jacques; Faller, Kiterie; Yeamans, Carmen; Stalin, Catherine; Gutierrez-Quintana, Rodrigo


    The objectives of this study were: To investigate computer-assisted digital radiographic measurement of Cobb angles in dogs with congenital thoracic vertebral malformations, to determine its intra- and inter-observer reliability and its association with the presence of neurological deficits. Medical records were reviewed (2009-2013) to identify brachycephalic screw-tailed dog breeds with radiographic studies of the thoracic vertebral column and with at least one vertebral malformation present. Twenty-eight dogs were included in the study. The end vertebrae were defined as the cranial end plate of the vertebra cranial to the malformed vertebra and the caudal end plate of the vertebra caudal to the malformed vertebra. Three observers performed the measurements twice. Intraclass correlation coefficients were used to calculate the intra- and inter-observer reliabilities. The intraclass correlation coefficient was excellent for all intra- and inter-observer measurements using this method. There was a significant difference in the kyphotic Cobb angle between dogs with and without associated neurological deficits. The majority of dogs with neurological deficits had a kyphotic Cobb angle higher than 35°. No significant difference in the scoliotic Cobb angle was observed. We concluded that the computer assisted digital radiographic measurement of the Cobb angle for kyphosis and scoliosis is a valid, reproducible and reliable method to quantify the degree of spinal curvature in brachycephalic screw-tailed dog breeds with congenital thoracic vertebral malformations.

  7. Computer-assisted radiographic calculation of spinal curvature in brachycephalic "screw-tailed" dog breeds with congenital thoracic vertebral malformations: reliability and clinical evaluation.

    Julien Guevar

    Full Text Available The objectives of this study were: To investigate computer-assisted digital radiographic measurement of Cobb angles in dogs with congenital thoracic vertebral malformations, to determine its intra- and inter-observer reliability and its association with the presence of neurological deficits. Medical records were reviewed (2009-2013 to identify brachycephalic screw-tailed dog breeds with radiographic studies of the thoracic vertebral column and with at least one vertebral malformation present. Twenty-eight dogs were included in the study. The end vertebrae were defined as the cranial end plate of the vertebra cranial to the malformed vertebra and the caudal end plate of the vertebra caudal to the malformed vertebra. Three observers performed the measurements twice. Intraclass correlation coefficients were used to calculate the intra- and inter-observer reliabilities. The intraclass correlation coefficient was excellent for all intra- and inter-observer measurements using this method. There was a significant difference in the kyphotic Cobb angle between dogs with and without associated neurological deficits. The majority of dogs with neurological deficits had a kyphotic Cobb angle higher than 35°. No significant difference in the scoliotic Cobb angle was observed. We concluded that the computer assisted digital radiographic measurement of the Cobb angle for kyphosis and scoliosis is a valid, reproducible and reliable method to quantify the degree of spinal curvature in brachycephalic screw-tailed dog breeds with congenital thoracic vertebral malformations.

  8. Analysis and calculation method of reliability of anchored retaining wall%锚杆挡土墙可靠度分析与计算方法

    唐仁华; 陈昌富


    A series-parallel model of rib beam-anchor system in reliability analyses of anchored retaining wall is presented. Regarding the rib beam as a continuous beam and the anchors as an elastic support, introducing a composite stiffness coefficient of anchor and the soil around anchorage section, the application loads acting on each anchor are obtained by displacement method. Considering the correlation of performance functions, based on the system reliability theory, a series system of three failure models for single anchor and a parallel system for multiple anchors are developed, while the calculation method of system reliability for the two systems is derived. The corresponding program of new method herein is used to compute the reliability in an engineering example. The calculation results show that the three failure models for single anchor are related and they have different effects on anchor's reliability, yet the parallel system failure probability of three anchors is approximately equal to sum of the three single anchor's failure probability at the condition of other anchors is not failure.%提出了锚杆挡墙中肋柱锚杆体系的串-并联模型.将肋柱视为连续梁,锚杆视为弹性支座,引入锚杆与锚固段周围岩土体的复合刚度系数,用位移法导出了各根锚杆所受荷载的统一计算公式.考虑各功能函数之间的相关性,运用系统可靠性理论,提出了单根锚杆3种破坏模式的串联系统与多根锚杆并联系统的体系可靠度计算方法,并编制了计算程序.对一工程实例进行计算,并对计算结果进行了分析,发现单根锚杆的3种失效模式并非相互独立,每种失效模式对锚杆可靠度的影响也不一样,而3根锚杆并联系统的失效概率近似等于在其他锚杆均未破坏的条件下每根锚杆单独失效概率之和.

  9. Reliable calculation of the efficacy of non-surgical and surgical treatment of obstructive sleep apnea revisited.

    Ravesloot, M J L; de Vries, N


    Various treatment methods exist to treat obstructive sleep apnea (OSA); continuous positive airway pressure (CPAP) is considered the gold standard. It is however a clinical reality that the use of CPAP is often cumbersome. CPAP treatment is considered compliant when used ≥ 4 h per night as an average over all nights observed. Surgery, on the other hand, is regarded as successful when the apnea hypopnea index (AHI) drops at least 50% and is reduced below 20/h postoperatively in patients whose preoperative AHI was > 20/h. The effectiveness of CPAP compliance criteria can be questioned, just as the effectiveness of surgical success criteria has often been questioned. The aim of the study was to compare non optimal use of optimal therapy (CPAP) with the continuous effect (100%) of often non optimal therapy (surgery). Using mathematical function formulas, the effect on the AHI of various treatment modalities and their respective compliance and success criteria were calculated. The more severe the AHI, the more percentage of total sleep time (TST) CPAP must be used to significantly reduce the AHI. Patients with moderate OSA reduce the AHI by 33.3% to 48.3% when using CPAP 4 h/ night (AHI 0-5, respectively). The required nightly percentage use rises as one reduces the AHI target to < 5. CPAP must be used 66.67% to 83.33% per night to reduce the AHI below 5 (AHI of 0 while using CPAP). Using a mean AHI in CPAP therapy is more realistic than using arbitrary compliance rates, which, in fact, hide insufficient reductions in AHI.

  10. Convergence and reliability of the Rehr-Albers formalism in multiple-scattering calculations of photoelectron diffraction

    Chen, Y.; García de Abajo, F. J.; Chassé, A.; Ynzunza, R. X.; Kaduwela, A. P.; van Hove, M. A.; Fadley, C. S.


    The Rehr-Albers (RA) separable Green's-function formalism, which is based on an expansion series, has been successful in speeding up multiple-scattering cluster calculations for photoelectron diffraction simulations, particularly in its second-order version. The performance of this formalism is explored here in terms of computational speed, convergence over orders of multiple scattering, over orders of approximation, and over cluster size, by comparison with exact cluster-based formalisms. It is found that the second-order RA approximation [characterized by (6×6) scattering matrices] is adequate for many situations, particularly if the initial state from which photoemission occurs is of s or p type. For the most general and quantitative applications, higher-order versions of RA may become necessary for d initial states [third-order, i.e., (10×10) matrices] and f initial states [fourth-order, i.e., (15×15) matrices]. However, the required RA order decreases as an electron wave proceeds along a multiple-scattering path, and this can be exploited, together with the selective and automated cutoff of weakly contributing matrix elements and paths, to yield computer time savings of at least an order of magnitude with no significant loss of accuracy. Cluster sizes of up to approximately 100 atoms should be sufficient for most problems that require about 5% accuracy in diffracted intensities. Excellent sensitivity to structure is seen in comparisons of second-order theory with variable geometry to exact theory as a fictitious ``experiment.'' Our implementation of the Rehr-Albers formalism thus represents a versatile, quantitative, and efficient method for the accurate simulation of photoelectron diffraction.

  11. New method of calculating fuzzy reliability of hydraulic cylinder stability%液压缸稳定性模糊可靠度计算的新方法

    龚相超; 胡百鸣; 韩芳


    There are many factors to influence the critical press of the hydraulic cylinder. The action mechanism is not entirely clear about how various parts of the hydraulic cylinder work on its stability, moreover, the load of the hydraulic cylinder is fuzzy and random. In the paper, the fuzzy reliability of the hydraulic cylinder stability is calculated according to mechanical fuzzy reliability theory, which provides an important reference for the design of the hydraulic cylinder. In addition, linear membership function is used for the critical pressure of the hydraulic cylinder, and the load is a kind of random variable which is normallydistributed. The calculation example shows that the method is effective.%根据机械模糊可靠性理论,笔者计算了液压缸稳定性的模糊可靠度,为液压缸设计提供了一个重要的参照指标。计算液压缸临界压力采用了线性隶属度函数,工作载荷为正态分布的随机变量,计算实例证明了该计算方法的有效性。

  12. Residual Mix Calculation at the Heart of Reliable Electricity Disclosure in Europe—A Case Study on the Effect of the RE-DISS Project

    Markus Klimscheffskij


    Full Text Available In the EU, electricity suppliers are obliged to disclose to their customers the energy origin and environmental impacts of sold electricity. To this end, guarantees of origin (GOs are used to explicitly track electricity generation attributes to individual electricity consumers. When part of a reliable electricity disclosure system, GOs deliver an important means for consumers to participate in the support of renewable power. In order to be considered reliable, GOs require the support of an implicit disclosure system, a residual mix, which prevents once explicitly tracked attributes from being double counted in a default energy mix. This article outlines the key problems in implicit electricity disclosure: (1 uncorrected generation statistics used for implicit disclosure; (2 contract-based tracking; (3 uncoordinated calculation within Europe; (4 overlapping regions for implicit disclosure; (5 active GOs. The improvements achieved during the RE-DISS project (04/2010-10/2012 with regard to these problems have reduced the total implicit disclosure error by 168 TWh and double counting of renewable generation attributes by 70 TWh, in 16 selected countries. Quantitatively, largest individual improvements were achieved in Norway, Germany and Italy. Within the 16 countries, a total disclosure error of 75 TWh and double counting of renewable generation attributes of 36 TWh still reside after the end of the project on national level. Regarding the residual mix calculation methodology, the article justifies the implementation of a shifted transaction-based method instead of a production year-based method.

  13. Reduction of Error Rate in Reserve Calculation of Gravel Quarry%减少砂砾石料场储量计算的误差率

    向能武; 肖东佑; 司马世华


    Aggregate quarry reserves survey accuracy of Pakistan Karot Hydropower Station Project directly affects investment decisions of construction projects .Project department established QC team for improving original investigation techniques, reducing calculation error , and providing accurate data for project design .The team conducts standard management on tackling results .‘CATIA V5 based Three dimensional Geological Quarry Modeling Technique ’ is revised and approved by experts , thereby ensuring investigation and calculation accuracy of similar project quarry .%巴基斯坦Karot水电站工程骨料场储量勘测精准度,直接影响工程建设的投资决策。项目部成立QC小组,改进原勘测技术,减少计算误差,为工程设计提供了精确数据。小组对攻关成果进行标准化管理,重新修订“基于CATIA V5的三维地质料场建模技术”并通过专家评审,从而保证了类似工程料场的勘测计算精度。

  14. Reliability computation from reliability block diagrams

    Chelson, P. O.; Eckstein, E. Y.


    Computer program computes system reliability for very general class of reliability block diagrams. Four factors are considered in calculating probability of system success: active block redundancy, standby block redundancy, partial redundancy, and presence of equivalent blocks in the diagram.

  15. Derivation of Reliable Geometries in QM Calculations of DNA Structures: Explicit Solvent QM/MM and Restrained Implicit Solvent QM Optimizations of G-Quadruplexes.

    Gkionis, Konstantinos; Kruse, Holger; Šponer, Jiří


    Modern dispersion-corrected DFT methods have made it possible to perform reliable QM studies on complete nucleic acid (NA) building blocks having hundreds of atoms. Such calculations, although still limited to investigations of potential energy surfaces, enhance the portfolio of computational methods applicable to NAs and offer considerably more accurate intrinsic descriptions of NAs than standard MM. However, in practice such calculations are hampered by the use of implicit solvent environments and truncation of the systems. Conventional QM optimizations are spoiled by spurious intramolecular interactions and severe structural deformations. Here we compare two approaches designed to suppress such artifacts: partially restrained continuum solvent QM and explicit solvent QM/MM optimizations. We report geometry relaxations of a set of diverse double-quartet guanine quadruplex (GQ) DNA stems. Both methods provide neat structures without major artifacts. However, each one also has distinct weaknesses. In restrained optimizations, all errors in the target geometries (i.e., low-resolution X-ray and NMR structures) are transferred to the optimized geometries. In QM/MM, the initial solvent configuration causes some heterogeneity in the geometries. Nevertheless, both approaches represent a decisive step forward compared to conventional optimizations. We refine earlier computations that revealed sizable differences in the relative energies of GQ stems computed with AMBER MM and QM. We also explore the dependence of the QM/MM results on the applied computational protocol.

  16. Calculation of reserve capacity of wind power system with spinning reserve of wind turbine generators%考虑风电机组旋转备用的风电系统备用容量计算

    张静; 李生虎


    The concept and implementation algorithm of spinning reserve strategy of variable-speed wind turbine generators are proposed in this paper .Based on the controllability of the wind turbine generators ,power limits are set to decrease the reserve capacity requirement to the conventional u-nits .The K-means clustering algorithm is applied to aggregating the historical output data of wind farms to yield the probability distribution of spinning reserve caused by forecast error of wind power . Based on the prescribed degree of confidence of safe operation of power network ,the spinning reserve needed by the power system is quantified without or with the spinning reserve strategy of wind turbine generators .The numerical results show that the spinning reserve strategy of the wind turbine genera-tors and better complementary nature of wind resource of wind farm can reduce the spinning reserve capacity needed by the power system from the conventional units .Multiple wind farms are aggregated into an equivalent wind farm ,reducing the given value of dispatching power output of wind farms .%文章提出变速风电机组旋转备用概念和实现算法,设置风电场出力上限,利用风电机组出力可控性,实现风电场间互补备用,减少常规机组提供的备用容量。采用 K-均值聚类算法对风电场历史数据进行聚类分析,分析风电场功率预测偏差引起的风电系统备用需求的概率分布。设定电网安全运行置信度,计算常规机组所需提供的备用容量值。结果证明,风电机组旋转备用和良好的风场风资源互补性可以减少常规机组所需提供的旋转备用容量,多风场聚合为一个等值风场,可以减少调度出力给定值。

  17. Study on power system reliability and reserve optimization with wind power integration%风电并网后电力系统可靠性评估和备用优化研究

    余民; 杨旻宸; 蒋传文; 蒋小亮; 李子林


    An assessment method of power system reliability and reserve optimization is established based on Monte Carlo simulation and Particle Swarm Optimization (PSO) Algorithm to study the impact of wind power integration on power system reliability and reserve quantitatively. Firstly, the output probability distribution figure of a wind turbine generator is acquired by the historical statistics of wind speed, and the reliability of power system with wind power integration is assessed under different conditions by Monte Carlo. A reserve optimization model based on reliability indicators is designed, which adopts PSO algorithm to compare the system reserve capacity before the optimization and that after the optimization based on the given model. The result of tested example assessment shows that the impact on power system reliability differs with different access capacities, points and patterns. And the capacity credits of different wind farm capacities are obtained through the assessment, providing quantitative indicators for power system with wind power integration of different capacities. The effectiveness and necessity of reserve optimization with wind power integration are shown with further research which accesses a real power system. This work is supported by the National High Technology Research and Development Program of China (863 Program) (No. 2007AA05Z458)%为了定量研究风电并网对电力系统的可靠性和备用配置影响,基于蒙特卡罗方法和粒子群优化算法给出了一种风电并网后的电力系统可靠性评估和备用优化模型.利用历史风速数据统计得到风机的出力概率分布图,并利用蒙特卡罗算法,对各种条件下风电并网后的电力系统进行了可靠性评估.设计了一种基于可靠性指标的备用优化模型,利用粒子群算法对比优化前后所需备用容量的大小.测试算例评估结果表明,不同接入容量、接入点和接入方式对最后的电力系统可靠性影

  18. Internal reserves industrial corporations. Management of own sources of financing in the implementation of the various approaches to calculating depreciation bonus

    Koncipko Natal'ja Vladimirovna


    Full Text Available Reindustrialization of the national economy of Russia in the conditions of tightening economic sanctions poses industrial corporations, particularly with state participation, the task of effective and rational use of private sources of funding. Today it is largely depends on the chosen and implemented, in fact, depreciation strategy of the state. In this regard, the main scientific idea of the article is in the economic justification of the amounts of material benefit when implementing different approaches for the calculation of depreciation in real terms of modern tax legislation of the Russian Federation. The object of the study selected the process of formation of own sources of financing of economic activity in conditions of re-industrialization of the domestic industry. The study serve as a methodological approaches used in practice to develop the depreciation policy, including methods and techniques to calculate the material benefits of different scenarios for the replenishment of own sources of financing production. To the main scientific result of the research is proposed by the authors of the financial mechanism of the formation and replenishment of own sources of financing is presented as a multi-level relationship between subjects and objects, principles and methods, including scenarios, tools, and methods of forming the effective depreciation policy (strategy of individual corporations and their groups. The proposed definition of effective depreciation policy under which the table presents the calculation of depreciation using bonus depreciation linear and nonlinear methods, which show the maximization depreciation income and minimize tax exemptions. For example, the economic activities of industrial corporations proved the legality of obtaining the maximum tax values, on the one hand, and economic (material benefits, on the other, and in the current field of modern Russian tax legislation.

  19. A New Convenient Method for Calculating Dynamic Reserves and Water Influx in Water Driving Gas Reservoir%计算水驱气藏动态储量和水侵量的简易新方法

    胡俊坤; 李晓平; 张健涛; 张修明


    By calculating dynamic reserves and water influx of water driving gas reservoir,we propose a new convenient method for calculating dynamic reserves and water influx.According to material balance equation of water driving gas reservoir,we point out the chart of dimensionless extrapolated pressure and degree of reserve recovery in water driving gas reservoir.Based on curve matching as well as data of production performance and measuring pressure,we adjust the parameters to make the actual curve of dimensionless extrapolated pressure and degree of reserve recovery in water driving gas reservoir and the theoretical curve achieve a good fitting.According to parameters obtained by type curve match analysis,the dynamic reserves and water influx of water drive gas reservoir can be calculated,and the strength of the energy of the water body can be evaluated.It is not required for the new method to do any assumption of aquifer shape and size,the inputting data is easy to collect,and calculating process is simple.The case indicates that the new method is accurate and practical.%通过对水驱气藏动态储量和水侵量计算方法的研究,提出了计算水驱气藏动态储量和水侵量的简易新方法。新方法根据水驱气藏的物质平衡方程,作出了水驱气藏无因次视压力与采出程度的理论图版。根据图版拟合法的思想,结合水驱气藏的生产动态资料及测压资料,通过参数的调整,使得水驱气藏无因次视压力与采出程度的实际曲线与理论曲线达到好的拟合程度。最后根据图版拟合所得参数,通过相关计算即可确定水驱气藏的动态储量和水侵量,同时对水驱气藏水体能量的强弱进行评价。新方法不需要对水体形态和大小做任何假设,所需资料易获取,计算过程简便。实例计算表明,新方法计算结果准确,实用性强。

  20. Reliability of fluid systems

    Kopáček Jaroslav


    Full Text Available This paper focuses on the importance of detection reliability, especially in complex fluid systems for demanding production technology. The initial criterion for assessing the reliability is the failure of object (element, which is seen as a random variable and their data (values can be processed using by the mathematical methods of theory probability and statistics. They are defined the basic indicators of reliability and their applications in calculations of serial, parallel and backed-up systems. For illustration, there are calculation examples of indicators of reliability for various elements of the system and for the selected pneumatic circuit.

  1. Power electronics reliability analysis.

    Smith, Mark A.; Atcitty, Stanley


    This report provides the DOE and industry with a general process for analyzing power electronics reliability. The analysis can help with understanding the main causes of failures, downtime, and cost and how to reduce them. One approach is to collect field maintenance data and use it directly to calculate reliability metrics related to each cause. Another approach is to model the functional structure of the equipment using a fault tree to derive system reliability from component reliability. Analysis of a fictitious device demonstrates the latter process. Optimization can use the resulting baseline model to decide how to improve reliability and/or lower costs. It is recommended that both electric utilities and equipment manufacturers make provisions to collect and share data in order to lay the groundwork for improving reliability into the future. Reliability analysis helps guide reliability improvements in hardware and software technology including condition monitoring and prognostics and health management.

  2. Ultrasound in evaluating ovarian reserve

    Eman Ahmaed Shawky Sabek


    Full Text Available The objective of this study was to compare the diagnostic accuracy of transvaginal ultrasound (TVS, as a less invasive technique instead of hormonal assay to evaluate the ovarian reserve. This study included fifty-five females with breast cancer and we compared the ovarian reserve for these patients by hormonal assay through measuring the serum AntiMullerian Hormone (AMH level and follicular stimulating hormone (FSH level before and after chemotherapy, and by transvaginal ultrasound through the ovarian volume (OV calculation and counting the Antral follicles (AFC before and after chemotherapy treatment. There was decline in the AntiMullerian Hormone level after chemotherapy by 27 ± 11.19% and decrease in the Antral follicle counts by 21 ± 13.43%. In conclusion there was strong relation between AMH level and AFC which makes the use of transvaginal ultrasound is a reliable alternative method to the hormonal assay to detect the ovarian reserve.

  3. Ovarian reserve

    Macklon, NS; Fauser, BCJM


    The tendency to delay childbirth has increased the importance of ovarian reserve as a determinant of infertility treatment outcome. In the context of assisted reproduction technology, effective strategies to overcome the impact of ovarian aging and diminished ovarian reserve on pregnancy chances rem

  4. 基于矿床实体模型的地质储量计算方法研究%Calculation Method of Geological Reserve Based on Solid Model of Deposit

    赵浩; 白润才; 刘光伟; 王金金


    矿床三维地质模型是实现“数字矿山”的基础,本文以AutoCAD为平台,利用钻孔数据、断层数据等建立矿床三维地质模型,提出了一种快速构建矿床三维地质实体模型的方法——包络面构模法。在建立矿床三维地质模型的基础上,介绍了一种基于矿床三维地质实体模型的储量计算方法,实现了矿床三雏地质模型上任意闭合区域资源储量的查询,与传统地质储量计算方法相比,提高了计算的速度与精度。%3D geological model of deposit is the basis of realizing digital mine . By using borehole and fault data, three-dimensional geological model of deposit is constructed in the platform of AutoCAD. A rapid method of constructing 3D geological solid model of deposit is proposed , which is called Envelop Surface Model. On the basis of 3 D geological solid model of deposit, a calculation method of reserve based on 3D geological solid model of deposit is introduced,which realizes the inquiry reserve of any closed region on 3D geological model of deposit, and speeds up the calculation and accuracy compared with traditional mine reserve.

  5. How reliable are gas-phase proton affinity values of small carbanions? A comparison of experimental data with values calculated using Gaussian-3 and CBS compound methods

    Danikiewicz, Witold


    Gas-phase proton affinities (PA) of a series of 25 small, aliphatic carbanions were computed using different Gaussian-3 methods: G3, G3(B3LYP), G3(MP2) and G3(MP2, B3LYP) and Complete Basis Set Extrapolation methods: CBS-4M, CBS-Q, CBS-QB3, and CBS-APNO. The results were compared with critically selected experimental data. The analysis of the results shows that for the majority of the studied molecules all compound methods (Gaussian-3 and CBS), except for CBS-4M, give comparable results, which differ no more than +/-2 kcal mol-1 from the experimental data. Taking into account the calculation time, G3(MP2) and G3(MP2, B3LYP) methods offer the best compromise between accuracy and computational cost. As an additional proof, the results obtained by these two methods were compared with the values obtained using CCSD(T) ab initio method with large basis set. It was found also that some of the published experimental data are erroneous and should be corrected. The results described in this work show that for the majority of the studied compounds PA values calculated using compound methods can be used with the same or even higher confidence as the experimental ones because even the largest differences between Gaussian-3 and CBS methods listed above are still comparable with the accuracy of the typical PA measurements.

  6. Estimating coal reserves using a support vector machine

    LIU Wen-kai; WANG Rui-fang; ZHENG Xiao-juan


    The basic principles of the Support Vector Machine (SVM) are introduced in this paper. A specific process to establish an SVM prediction model is given. To improve the precision of coal reserve estimation, a support vector machine method, based on statistical learning theory, is put forward. The SVM model was trained and tested by using the existing exploration and exploitation data of Chencun mine of Yima bureau's as the input data. Then coal reserves within a particular region were calculated. These cal-culated results and the actual results of the exploration block were compared. The maximum relative error was 10.85%, within the scope of acceptable error limits. The results show that the SVM coal reserve calculation method is reliable. This method is simple, practical and valuable.

  7. Reliability analysis of offshore jacket structures with wave load on deck using the Model Correction Factor Method

    Sørensen, John Dalsgaard; Friis-Hansen, P.; Nielsen, J.S.


    Traditionally, deterministic pushover analyses are performed for steel-jacket offshore platforms in order to calculate RSR (Reserve Strength Ratio) values as the representative reliability measure for the total collapse of the structure. In this paper, reliability analyses are performed for total...

  8. Reliability Analysis of Offshore Jacket Structures with Wave Load on Deck using the Model Correction Factor Method


    Traditionally deterministic push-over analyses are performed for steel-jacket offshore platforms in order to calculate RSR (Reserve Strength Ratio) values as the representative reliability measure for total collapse of the structure. In this paper reliability analyses are performed for total...

  9. MEMS reliability

    Hartzell, Allyson L; Shea, Herbert R


    This book focuses on the reliability and manufacturability of MEMS at a fundamental level. It demonstrates how to design MEMs for reliability and provides detailed information on the different types of failure modes and how to avoid them.

  10. Structural reliability calculation by using moving least squares method of response surface%响应面的移动最小二乘法结构可靠性计算



    For the problems as large amount of calculation,not high accuracy,easy to produce singular solution and calculation can be done only performance function is known in the conventional response surface methodology widely adopted for structural reliability computation,first,based on the principle of least squares,under the condition that only the performance function value corresponding to the design checking point is known,by using the properties of weight function as compactly supported,non-negativity,smoothness,decrease,and selecting the design checking point in the domain of influence,the paper presents that most probable failure point and reliability index of the structure can be calculated by applying the least squares method to generate response surface function through iteration and the combining with first order reliability method,until the calculated adjacent two reliability indexes can meet the given error.The paper gives a feasible algorithm,which can carry out calculation without necessary to know the performance function,even the type of the performance function.Examples show that this method with less number of iterations,can obtain the most probable failure point and reliability index of structure in the higher accuracy and with less number of iterations.%针对目前在结构可靠性计算中被广泛应用的传统响应面法存在计算量大,精确度不高,容易产生奇异解,必须知道功能函数才能计算等问题.首先根据最小二乘原理,在只需知道设计验算点对应的功能函数值的情况下,利用权函数的紧支性、非负性、光滑性、递减性等性质,在影响域内应用选取的设计验算点,提出了用移动最小二乘法通过迭代生成响应面函数,然后结合一阶可靠性方法,计算结构的最大失效点与可靠性指标.通过反复迭代,直到计算的相邻两次的可靠性指标满足所给的误差为止.给出了切实可行的算法,该算法不需要知道功能函数,甚

  11. CONFIABILIDAD DE LOS CÁLCULOS ESPECIALES DE LA OXIGENACIÓN DE MUESTRAS VENOSAS CENTRALES EN CIRUGÍA CARDÍACA / Reliability of the special calculations of oxygenation from central venous samples in cardiac surgery

    Pedro A. Hidalgo Menéndez


    Full Text Available Resumen Introducción y objetivos: Diferentes mecanismos se implican en la captación, transporte, entrega y utilización del oxígeno en los organismos vivos, y cada uno de ellos puede afectarse en el enfermo grave. El propósito de este trabajo fue conocer la confiabilidad de los cálculos especiales de la oxigenación, procedentes de muestras venosas centrales. Método: Se realizó un estudio prospectivo con 22 pacientes a los que se les practicó cirugía cardíaca, en los que se compararon los cálculos especiales obtenidos de muestras venosas centrales con los venosos-mixtos. Resultados: Se encontró correlación estadística significativa entre la diferencia arteriovenosa de oxígeno, el cortocircuito y la saturación venosa de hemoglobina oxigenada. Sin embargo, se halló un bajo por ciento de fiabilidad al aplicarles los criterios protocolizados; pero fue factible mediante ecuaciones de regresión, lograr una corrección altamente significativa (p < 0,01, que elevó la fiabilidad a más del 90 %. Conclusiones: Las muestras venosas centrales constituyen una alternativa recomendable para obtener cálculos especiales de la oxigenación durante la cirugía cardíaca. / Abstract Introduction and Objectives: Different mechanisms are involved in the uptake, transportation, delivery and utilization of oxygen in living organisms, and each of them may be affected in the severely ill patient. The purpose of this study was to determine the reliability of the special calculations of oxygenation, from central venous samples. Methods: A prospective study was performed on 22 patients who underwent cardiac surgery, and in which special calculations obtained from central venous samples were compared to mixed-venous samples calculations. Results: A statistically significant correlation among the arteriovenous oxygen difference, the shunt and the venous hemoglobin oxygen saturation was found. However, a small percentage of reliability was found when

  12. Software reliability

    Bendell, A


    Software Reliability reviews some fundamental issues of software reliability as well as the techniques, models, and metrics used to predict the reliability of software. Topics covered include fault avoidance, fault removal, and fault tolerance, along with statistical methods for the objective assessment of predictive accuracy. Development cost models and life-cycle cost models are also discussed. This book is divided into eight sections and begins with a chapter on adaptive modeling used to predict software reliability, followed by a discussion on failure rate in software reliability growth mo


    Gonzalez Cruz, D.J.


    Venezuela is an important player in the energy world, because of its hydrocarbons reserves. The process for calculating oil and associated gas reserves is described bearing in mind that 90% of the gas reserves of Venezuela are associated to oil. Likewise, an analysis is made of the oil reserves figures from 1975 to 2003. Reference is also made to inconsistencies found by international experts and the explanations offered in this respect by the Ministry of Energy and Petroleum (MENPET) and Petroleos de Venezuela (PDVSA) regarding the changes that took place in the 1980s. In turn, Hubbert's Law is explained to determine peak production of conventional oil that a reservoir or field will reach, as well as its relationship with remaining reserves. Emphasis is placed on the interest of the United Nations on this topic. The reserves of associated gas are presented along with their relationship with the different crude oils that are produced and with injected gas, as well as with respect to the possible changes that would take place in the latter if oil reserves are revised. Some recommendations are submitted so that the MENPET starts preparing the pertinent policies ruling reserves. (auth)

  14. Artificial Neural Reliability Calculating Method Based on Uniform Test Network%基于均匀试验人工神经网络的实用可靠性方法



    This paper presents a design of a new reliability calculation method based on uniform test, which organically combines artificial intelligence network. Artificial neural networks abandons the finite element method (FEM) and applies this method,because the new law can greatly reduce the amount of computation. First, according to the distribution of the random variable,limited samples are extracted by uniform test, which are taken as for the input parameters finite element analysis. Secondly, based on the finite element analysis results, the limited training samples are used to construct the optimal artificial neural network. Optimal artificial neural network generalization ability is applied to obtain a valid response, and then the reliability index of the structural system is calculated. Finally, this calculation method provides a new attempt for reliability analysis in the actual testing of complex systems, which is proved to be practical and effective.%根据均匀试验的设计提出了一种全新的可靠性计算方法,它有机地综合了人工智能网络.人工神经网络弃用有限单元法(FEM)而改用该方法,一个根本原因在于它能极大地减少计算量.首先,根据随机变量分布情况,通过均匀试验提取出有限样本,将它们看作是有限元法分析的输入参数.其次,基于有限元分析结果利用这些有限的训练样本构建最优的人工神经网络.利用最优人工神经网络的泛化能力,随机得到一个有效的响应值,然后计算出结构系统的可靠性指数.最后,这一计算方法还为进行可靠性分析提供新尝试,在对复杂系统进行实际试验时该方法表现得切实可行且有效.

  15. 威布尔分布对整体旋转式斯特林制冷机的可靠性计算%Calculation on the reliability of rotary Stirling cryocoolers by Weibull Law

    罗高乔; 范仙红; 何世安


    介绍了威布尔分布的计算过程,对Thales整体旋转式斯特林制冷机的可靠性试验数据进行了分析,比较了威布尔分布可靠性计算的数值解析法与图估法的计算结果,总结了Thales整体旋转式斯特林制冷机的可靠性计算过程和加速因子的确定,为国内同类产品可靠性试验方案和寿命计算方法提供借鉴.%This article described the calculation of Weibull Law and analyzed the experimental data on the reliability of Tha-les rotary Stirling cryocoolers. The comparison of calculating results between Weibull Law and figure - estimation method was conducted.It summerized the calculation process and speeding factor of Thales rotary Stirling cryocooler.

  16. Hawaii Electric System Reliability

    Loose, Verne William [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Silva Monroy, Cesar Augusto [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)


    This report addresses Hawaii electric system reliability issues; greater emphasis is placed on short-term reliability but resource adequacy is reviewed in reference to electric consumers’ views of reliability “worth” and the reserve capacity required to deliver that value. The report begins with a description of the Hawaii electric system to the extent permitted by publicly available data. Electrical engineering literature in the area of electric reliability is researched and briefly reviewed. North American Electric Reliability Corporation standards and measures for generation and transmission are reviewed and identified as to their appropriateness for various portions of the electric grid and for application in Hawaii. Analysis of frequency data supplied by the State of Hawaii Public Utilities Commission is presented together with comparison and contrast of performance of each of the systems for two years, 2010 and 2011. Literature tracing the development of reliability economics is reviewed and referenced. A method is explained for integrating system cost with outage cost to determine the optimal resource adequacy given customers’ views of the value contributed by reliable electric supply. The report concludes with findings and recommendations for reliability in the State of Hawaii.

  17. Hawaii electric system reliability.

    Silva Monroy, Cesar Augusto; Loose, Verne William


    This report addresses Hawaii electric system reliability issues; greater emphasis is placed on short-term reliability but resource adequacy is reviewed in reference to electric consumers' views of reliability %E2%80%9Cworth%E2%80%9D and the reserve capacity required to deliver that value. The report begins with a description of the Hawaii electric system to the extent permitted by publicly available data. Electrical engineering literature in the area of electric reliability is researched and briefly reviewed. North American Electric Reliability Corporation standards and measures for generation and transmission are reviewed and identified as to their appropriateness for various portions of the electric grid and for application in Hawaii. Analysis of frequency data supplied by the State of Hawaii Public Utilities Commission is presented together with comparison and contrast of performance of each of the systems for two years, 2010 and 2011. Literature tracing the development of reliability economics is reviewed and referenced. A method is explained for integrating system cost with outage cost to determine the optimal resource adequacy given customers' views of the value contributed by reliable electric supply. The report concludes with findings and recommendations for reliability in the State of Hawaii.

  18. Application of fine logging interpretation in reserve calculation, Puguang Gas Field%测井精细解释在普光气田储量计算中的应用

    钱勤; 冯明刚; 彭劲; 李淑荣; 王燕


    The mineral composition and porosity interpreted by conventional logging are obviously different from core analysis, hence are not qualified for reserve prediction. In view of this, it is very important to carry out fine logging interpretation. A core hole in the Puguang Gas Field was chosen as the key to study the error between core and logging analysis. Mineral composition was calculated from PE curves and other logging data. Based on CNL and DEN as well as proper programming, porosity was calculated. New software to process the logging data from the Puguang Gas Field was made. The precision of logging interpretation was improved obviously, which backed up for the parameter research and reserve demonstration in the Puguang Gas Field.%普光气田应用常规测井解释方法计算得到的矿物成分含量、孔隙度与岩心分析结果存在较大偏差,难以满足储量申报需要.因此,开展测井精细解释攻关研究显得尤为重要.首先选取普光气田取心并作为关键井,开展岩心刻度测井精细解释研究;其次利用PE曲线并结合其余测井资料计算储层矿物成分含量;最后分储层类型优选权值系数将中子和密度孔隙度进行合理组合,计算储层孔隙度,并编制适用普光气田的测井资料处理软件.将测井精细解释结论同取心井岩心分析资料进行对比分析,测井处理解释精度大幅提高.该测井精细解释方法有力支撑了普光气田储量参数的研究及探明储量的申报.

  19. Reliability and Its Quantitative Measures

    Alexandru ISAIC-MANIU


    Full Text Available In this article is made an opening for the software reliability issues, through wide-ranging statistical indicators, which are designed based on information collected from operating or testing (samples. It is developed the reliability issues also for the case of the main reliability laws (exponential, normal, Weibull, which validated for a particular system, allows the calculation of some reliability indicators with a higher degree of accuracy and trustworthiness

  20. Cost Analysis Method for Estimating Dynamic Reserve Considering Uncertainties in Supply and Demand

    Kyung-bin Kwon


    Full Text Available The use of appropriate hourly reserve margins can maintain power system security by balancing supply and demand in the presence of errors in the forecast demand, generation outages, or errors in the forecast of wind power generation. Because the cost of unit commitment increases with larger reserve margins, cost analysis to determine the most economical reserve margin is an important issue in power system operation. Here, we define the “short-term reliability of balance” and describe a method to determine the reserve margin based on the short-term reliability of balance. We describe a case study, in which we calculate the reserve margin using this method with various standards of short-term reliability of balance. A cost analysis is then performed to determine the most economic standard, and a comparison between our method and a conventional method is carried out. The results show that our method with an economic short-term reliability of balance enables more reliable and efficient operation of the power system. Moreover, with an hourly reserve margin, we show that an increase in wind power generation can result in a significant decrease in the operating cost, which makes wind power generation economically viable.

  1. Further development of the structure mechanics analysis method for the calculation of the structure reliability of passive components, phase II. Final report; Weiterentwicklung der strukturmechanischen Analysemethodik zur Bestimmung der Strukturzuverlaessigkeit passiver Komponenten, Phase II. Abschlussbericht

    Grebner, H.; Wang, Y.; Schmipfke, T.; Sievers, J.


    Within the framework of research project RS 1163 the computer code PROST for the quantitative assessment of the structural reliability of pipe components has been further developed. Thereby models were provided and tested for the consideration of the damage mechanism 'corrosion' to determine leak and break probabilities in cylindrical structures of ferritic and austenitic reactor steels. These models are now additionally available to the model for the consideration of the damage mechanism 'fatigue'. Furthermore, the application range of the code was extended to complex geometries in regards to loading and boundary conditions. Additional code modules were developed to be able to include the results of finite element (FE) calculations. The extended analysis method was tested, amongst others, in the context of calculations for a cracked feedwater nozzle of a steam generator under thermal-mechanical cyclic loading. The stress on cracks was calculated with the FE-method. For the determination of leak probabilities the crack growth due to fatigue was estimated taking into account the ''mixed-mode'' - loading within the J-integral vector approach. Altogether, the analyses show that with the provided flexible probabilistic analysis method quantitative determination of leak probabilities of a detected or postulated crack in a complex structure geometry under thermal-mechanical loading as function of the operating time in the range of very small probability values (<1.0 E-8) to large values (>1.0 E-2) are possible. The next development steps should comprise especially the improvement of the accuracy of the method to determine break probabilities and also the consideration of approaches on crack formation due to the damage mechanisms 'fatigue' and 'corrosion', based on evaluations of national and international operating experiences.

  2. Demand Response Spinning Reserve Demonstration

    Eto, Joseph H.; Nelson-Hoffman, Janine; Torres, Carlos; Hirth,Scott; Yinger, Bob; Kueck, John; Kirby, Brendan; Bernier, Clark; Wright,Roger; Barat, A.; Watson, David S.


    The Demand Response Spinning Reserve project is a pioneeringdemonstration of how existing utility load-management assets can providean important electricity system reliability resource known as spinningreserve. Using aggregated demand-side resources to provide spinningreserve will give grid operators at the California Independent SystemOperator (CAISO) and Southern California Edison (SCE) a powerful, newtool to improve system reliability, prevent rolling blackouts, and lowersystem operating costs.

  3. Reliability Engineering

    Lazzaroni, Massimo


    This book gives a practical guide for designers and users in Information and Communication Technology context. In particular, in the first Section, the definition of the fundamental terms according to the international standards are given. Then, some theoretical concepts and reliability models are presented in Chapters 2 and 3: the aim is to evaluate performance for components and systems and reliability growth. Chapter 4, by introducing the laboratory tests, puts in evidence the reliability concept from the experimental point of view. In ICT context, the failure rate for a given system can be

  4. Reliability and construction control

    Sherif S. AbdelSalam


    Full Text Available The goal of this study was to determine the most reliable and efficient combination of design and construction methods required for vibro piles. For a wide range of static and dynamic formulas, the reliability-based resistance factors were calculated using EGYPT database, which houses load test results for 318 piles. The analysis was extended to introduce a construction control factor that determines the variation between the pile nominal capacities calculated using static versus dynamic formulae. From the major outcomes, the lowest coefficient of variation is associated with Davisson’s criterion, and the resistance factors calculated for the AASHTO method are relatively high compared with other methods. Additionally, the CPT-Nottingham and Schmertmann method provided the most economic design. Recommendations related to a pile construction control factor were also presented, and it was found that utilizing the factor can significantly reduce variations between calculated and actual capacities.

  5. Handbook on loss reserving

    Schmidt, Klaus; Schnaus, Anja


    This handbook presents the basic aspects of actuarial loss reserving. Besides the traditional methods, it also includes a description of more recent ones and a discussion of certain problems occurring in actuarial practice, like inflation, scarce data, large claims, slow loss development, the use of market statistics, the need for simulation techniques and the task of calculating best estimates and ranges of future losses. In property and casualty insurance the provisions for payment obligations from losses that have occurred but have not yet been settled usually constitute the largest item on the liabilities side of an insurer's balance sheet. For this reason, the determination and evaluation of these loss reserves is of considerable economic importance for every property and casualty insurer. Actuarial students, academics as well as practicing actuaries will benefit from this overview of the most important actuarial methods of loss reserving by developing an understanding of the underlying stochastic models...

  6. A computational model for reliability calculation of steam generators from defects in its tubes; Um modelo computacional para o calculo da confiabilidade de geradores de vapor a partir de defeitos em seus tubos

    Rivero, Paulo C.M.; Melo, P.F. Frutuoso e [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear


    Nowadays, probability approaches are employed for calculating the reliability of steam generators as a function of defects in their tubes without any deterministic association with warranty assurance. Unfortunately, probability models produce large failure values, as opposed to the recommendation of the U.S. Code of Federal Regulations, that is, failure probabilities must be as small as possible In this paper, we propose the association of the deterministic methodology with the probabilistic one. At first, the failure probability evaluation of steam generators follows a probabilistic methodology: to find the failure probability, critical cracks - obtained from Monte Carlo simulations - are limited to have length's in the interval defined by their lower value and the plugging limit one, so as to obtain a failure probability of at most 1%. The distribution employed for modeling the observed (measured) cracks considers the same interval. Any length outside the mentioned interval is not considered for the probability evaluation: it is approached by the deterministic model. The deterministic approach is to plug the tube when any anomalous crack is detected in it. Such a crack is an observed one placed in the third region on the plot of the logarithmic time derivative of crack lengths versus the mode I stress intensity factor, while for normal cracks the plugging of tubes occurs in the second region of that plot - if they are dangerous, of course, considering their random evolution. A methodology for identifying anomalous cracks is also presented. (author)

  7. Calculation of Noninformative Prior of Reliability Parameter and Initiating Event Frequency With Jeffreys Method%应用Jeffreys方法计算可靠性参数和始发事件频率的无信息先验

    何劼; 张彬彬


    在核电厂概率安全评价(PSA )分析中,有些始发事件频率或设备失效记录在工业界几乎无历史数据。为了计算这些无信息先验的可靠性参数和始发事件频率,可采用Bayesian统计学中的Jeffreys方法。本文阐述了Jeffreys先验和简化的受限无信息先验分布(SCNID )的数学原理,分别导出了Gamma-Poisson模型和Beta-Binomial模型的Jeffreys无信息先验公式和不确定性区间。结合反应堆冷却剂小破口失水事故(SLOCA)实例介绍了如何应用Jeffreys先验计算始发事件频率。结果表明,Jeffreys方法是一种计算无信息先验的有效方法。%In the probabilistic safety assessment (PSA ) of nuclear power plants ,there are few historical records on some initiating event frequencies or component failures in industry .In order to determine the noninformative priors of such reliability parameters and initiating event frequencies , the Jeffreys method in Bayesian statistics was employed . The mathematical mechanism of the Jeffreys prior and the simplified constrained noninformative distribution (SCNID) were elaborated in this paper .The Jeffreys noninformative formulas and the credible intervals of the Gamma-Poisson and Beta-Binomial models were introduced .As an example ,the small break loss-of-coolant accident (SLOCA) was employed to show the application of the Jeffreys prior in deter-mining an initiating event frequency .The result shows that the Jeffreys method is an effective method for noninformative prior calculation .

  8. Microelectronics Reliability


    convey any rights or permission to manufacture, use, or sell any patented invention that may relate to them. This report was cleared for public release...testing for reliability prediction of devices exhibiting multiple failure mechanisms. Also presented was an integrated accelerating and measuring ...13  Table 2  T, V, F and matrix versus  measured  FIT

  9. A Stochastic Programming Model for Spinning Reserve of Power Grid Containing Wind Farms Under Constraint of Time-Varying Reliability%时变可靠性约束下含风电系统旋转备用的随机规划模型

    王雁凌; 许传龙; 岳巍澎


      After large-scale wind farms are connected with the grid, conspicuous contradiction between economy and reliability of power grid operation appears due to the limitation of traditional method determining spinning reserve. A stochastic programming model for spinning reserve of power grid connected with large-scale wind farms is built, which can flexibly allocate reliability weights in different time-intervals to implement the coordinated optimization of reliability within dispatching period. Fully considering cost differences among spinning reserves provided by different units, the built model permits units to bid prices of spinning reserves, and the minimization of generation cost, spinning reserve cost, and expected outage cost is taken as objective function to implement the maximization of whole economic benefits at generation side and consumer side. The built model can be applied to perform cost-benefit analysis for power grid containing wind farms and to provide decision-making foundation for dispatching departments to set reasonable reliability level. The built model is solved by particle swarm optimization (PSO) algorithm, and the effectiveness of above-mentioned model and algorithm is verified by simulation results of a 10-machine system.%  大规模风电并网后,系统运行经济性和可靠性之间的矛盾十分突出,传统确定旋转备用的方法存在较大的局限性。建立的含风系统旋转备用随机规划模型,能够根据系统容量冗余度,灵活分配各时段可靠性权重,实现调度周期内可靠性的协调优化。该模型充分考虑不同机组提供旋转备用的成本差异,允许机组对旋转备用进行报价,以发电成本、直接备用成本和期望停电成本三者之和最小为目标,实现发电侧和用户侧整体经济效益的最大化。应用该模型,可以对含风系统的旋转备用进行成本效益分析,为调度机构设置合理的可靠性水平提供决

  10. Reserve Growth in Oil Fields of West Siberian Basin, Russia

    Verma, Mahendra K.; Ulmishek, Gregory F.


    contains oil in Jurassic river-valley sandstones. Principal source rocks are organic-rich marine shales of the Volgian (uppermost Jurassic) Bazhenov Formation, which is 30-50 m (98- 164 feet) thick. Bazhenov-derived oils are mostly of medium gravity, and contain 0.8-1.3 percent sulfur and 2-5 percent paraffin. Oils in the Lower to Middle Jurassic clastics were sourced from lacustrine and estuarine shales of the Toarcian Togur Bed. These oils are medium to low gravity, with low sulfur (less than 0.25 percent) and high paraffin (commonly to 10 percent) contents. Among the 42 fields analyzed for reserve growth, 30 fields are located in the Middle Ob region, which includes the Samotlor field with reserves of more than 25 BBO and the Fedorov field with reserves of about 5 BBO. Data used in the study include year of discovery, year of first production, annual and cumulative production, and remaining reserves reported by Russian reserve categories (A+B+C1 and C2) in January of each year. Correlation of these Russian resource categories to U.S. categories of the Society of Petroleum Engineers classification is complex and somewhat uncertain. Reserve growth in oil fields of West Siberia was calculated using a newly developed Group Growth method, which requires that the total reserve (proven reserve plus cumulative production) of individual fields with an equal length of reserve record be added together starting with discovery year or the first production year. Then the annual growth factor (AGF), which is the ratio of total reserves of two consecutive years, is calculated for all years. Once AGFs have been calculated, the cumulative growth factor (CGF) is calculated by multiplying the AGFs of all the previous years. The CGF data are used to develop reserve growth models. The West Siberian oil fields show a 13-fold reserve growth 20 years after the discovery year and only about a 2-fold growth after the first production year. This difference is attributed to extensive exploration

  11. Grid reliability

    Saiz, P; Rocha, R; Andreeva, J


    We are offering a system to track the efficiency of different components of the GRID. We can study the performance of both the WMS and the data transfers At the moment, we have set different parts of the system for ALICE, ATLAS, CMS and LHCb. None of the components that we have developed are VO specific, therefore it would be very easy to deploy them for any other VO. Our main goal is basically to improve the reliability of the GRID. The main idea is to discover as soon as possible the different problems that have happened, and inform the responsible. Since we study the jobs and transfers issued by real users, we see the same problems that users see. As a matter of fact, we see even more problems than the end user does, since we are also interested in following up the errors that GRID components can overcome by themselves (like for instance, in case of a job failure, resubmitting the job to a different site). This kind of information is very useful to site and VO administrators. They can find out the efficien...

  12. Replacing reserve requirements

    Edward J. Stevens


    An examination of the fading significance of the Federal Reserve System's reserve requirements and the recent flowering of required clearing balances, a rapidly growing feature of Reserve Bank operations.

  13. Replacing reserve requirements

    Edward J. Stevens


    An examination of the fading significance of the Federal Reserve System's reserve requirements and the recent flowering of required clearing balances, a rapidly growing feature of Reserve Bank operations.

  14. Estimating Foreign Exchange Reserve Adequacy

    Abdul Hakim


    Full Text Available Accumulating foreign exchange reserves, despite their cost and their impacts on other macroeconomics variables, provides some benefits. This paper models such foreign exchange reserves. To measure the adequacy of foreign exchange reserves for import, it uses total reserves-to-import ratio (TRM. The chosen independent variables are gross domestic product growth, exchange rates, opportunity cost, and a dummy variable separating the pre and post 1997 Asian financial crisis. To estimate the risky TRM value, this paper uses conditional Value-at-Risk (VaR, with the help of Glosten-Jagannathan-Runkle (GJR model to estimate the conditional volatility. The results suggest that all independent variables significantly influence TRM. They also suggest that the short and long run volatilities are evident, with the additional evidence of asymmetric effects of negative and positive past shocks. The VaR, which are calculated assuming both normal and t distributions, provide similar results, namely violations in 2005 and 2008.

  15. Frontiers of reliability

    Basu, Asit P; Basu, Sujit K


    This volume presents recent results in reliability theory by leading experts in the world. It will prove valuable for researchers, and users of reliability theory. It consists of refereed invited papers on a broad spectrum of topics in reliability. The subjects covered include Bayesian reliability, Bayesian reliability modeling, confounding in a series system, DF tests, Edgeworth approximation to reliability, estimation under random censoring, fault tree reduction for reliability, inference about changes in hazard rates, information theory and reliability, mixture experiment, mixture of Weibul

  16. Optimal Power Management of a DISCO with Integrations of Reliability Considerations and Wind Farm Based on Benders Decomposition

    M. Baghdadi


    Full Text Available This paper presents a comprehensive framework model of a distribution company with security and reliability considerations. A probabilistic wind farm, which is a renewable energy resource, is modeled in this work. The requirement energy of distribution company can be either provided by distribution company's own distributed generations or purchased from power market. Two reliability indices as well as DC load flow equations are also considered in order to satisfy reliability and security constraints, respectively. Since allocating proper spinning reserve improves reliability level, the amount of spinning reserve will be calculated iteratively. In this work, all equations are expressed in a linear fashion in which unit commitment formulation depends on binary variables associated with only on/off of units. The benders decomposition method is used to solve security-based unit commitment.

  17. Oil Reserve Center Established


    Like other countries,China has started to grow its strategic oil reserve in case oil supplies are cut On December 18,2007,the National Development and Reform Commission(NDRC),China’s top economic planner,announced that the national oil reserve center has been officially launched.The supervisory system over the oil reserves has three levels: the energy department of the NDRC,the oil reserve center,and the reserve bases.

  18. Delta-Reliability

    Eugster, P.; Guerraoui, R.; Kouznetsov, P.


    This paper presents a new, non-binary measure of the reliability of broadcast algorithms, called Delta-Reliability. This measure quantifies the reliability of practical broadcast algorithms that, on the one hand, were devised with some form of reliability in mind, but, on the other hand, are not considered reliable according to the ``traditional'' notion of broadcast reliability [HT94]. Our specification of Delta-Reliability suggests a further step towards bridging the gap between theory and...

  19. Reliability Analysis of Wind Turbines

    Toft, Henrik Stensgaard; Sørensen, John Dalsgaard


    In order to minimise the total expected life-cycle costs of a wind turbine it is important to estimate the reliability level for all components in the wind turbine. This paper deals with reliability analysis for the tower and blades of onshore wind turbines placed in a wind farm. The limit states...... consideres are in the ultimate limit state (ULS) extreme conditions in the standstill position and extreme conditions during operating. For wind turbines, where the magnitude of the loads is influenced by the control system, the ultimate limit state can occur in both cases. In the fatigue limit state (FLS......) the reliability level for a wind turbine placed in a wind farm is considered, and wake effects from neighbouring wind turbines is taken into account. An illustrative example with calculation of the reliability for mudline bending of the tower is considered. In the example the design is determined according...

  20. Determining coal reserves in a mine field, accounting for the random nature of the change in the seam thickness. [USSR

    Smirenskii, M.M.; Rozhkova, N.B.


    A method is proposed for calculating the balanced coal reserves (shales) based on the probability distribution of values corresponding to the seam thickness. The approval tests for the method, which were performed in accordance with the conditions at the ''Osinnikovsk'' mine of the ''Yuzhkuzbassgol'' Production Union demonstrated that it is no less accurate than traditional methods, while the labor expended and volume of calculations are, on the average, cut in half. Additionally, the proposed method makes it possible to numerically evaluate the reliability of the calculations performed.

  1. Reserve valuation in electric power systems

    Ruiz, Pablo Ariel

    Operational reliability is provided in part by scheduling capacity in excess of the load forecast. This reserve capacity balances the uncertain power demand with the supply in real time and provides for equipment outages. Traditionally, reserve scheduling has been ensured by enforcing reserve requirements in the operations planning. An alternate approach is to employ a stochastic formulation, which allows the explicit modeling of the sources of uncertainty. This thesis compares stochastic and reserve methods and evaluates the benefits of a combined approach for the efficient management of uncertainty in the unit commitment problem. Numerical studies show that the unit commitment solutions obtained for the combined approach are robust and superior with respect to the traditional approach. These robust solutions are especially valuable in areas with a high proportion of wind power, as their built-in flexibility allows the dispatch of practically all the available wind power while minimizing the costs of operation. The scheduled reserve has an economic value since it reduces the outage costs. In several electricity markets, reserve demand functions have been implemented to take into account the value of reserve in the market clearing process. These often take the form of a step-down function at the reserve requirement level, and as such they may not appropriately represent the reserve value. The value of reserve is impacted by the reliability, dynamic and stochastic characteristics of system components, the system operation policies, and the economic aspects such as the risk preferences of the demand. In this thesis, these aspects are taken into account to approximate the reserve value and construct reserve demand functions. Illustrative examples show that the demand functions constructed have similarities with those implemented in some markets.

  2. Declination Calculator

    National Oceanic and Atmospheric Administration, Department of Commerce — Declination is calculated using the current International Geomagnetic Reference Field (IGRF) model. Declination is calculated using the current World Magnetic Model...

  3. VLSI Reliability in Europe

    Verweij, Jan F.


    Several issue's regarding VLSI reliability research in Europe are discussed. Organizations involved in stimulating the activities on reliability by exchanging information or supporting research programs are described. Within one such program, ESPRIT, a technical interest group on IC reliability was

  4. El factor de impacto Web de los archivos universitarios latinoamericanos: la fiabilidad de los motores de búsqueda para calcularlo Web Impact Factor of Latin American University Archives: reliability of calculations using search engines

    Isabel María Sanz Caballero


    Full Text Available El objetivo principal de la presente investigación consiste en analizar el Factor de Impacto Web (FIW de los Archivos Universitarios Latinoamericanos durante un periodo temporal de seis meses utilizando dos herramientas distintas para calcularlo: Google y Altavista. Los resultados demuestran que no existe correlación entre ambos motores a la hora de calcular el FIW de los Arhivos en cuestión, lo que permite concluir que el uso de distintas herramientas o motores utilizados para calcular el FIW interfiere en los resultados obtenidos, por lo que hay que tener cuidado al momento de establecer un ranking de calidad de los AUL, según su FIW.The main objective of this research is to analyze the Web Impact Factor (WIF of the Latin American University Archives during a six month period using two different analytical tools: Google and Altavista. The results show no correlation between the two engines when calculating the WIF of these Archives, allowing us to conclude that the use of different tools or engines to calculate the WIF affects the results, so that we must be careful when setting up a quality ranking of the LUA, according to their WIF.

  5. Adrenocortical reserves in hyperthyroidism.

    Agbaht, Kemal; Gullu, Sevim


    Explicit data regarding the changes in adrenocortical reserves during hyperthyroidism do not exist. We aimed to document the capability (response) of adrenal gland to secrete cortisol and DHEA-S during hyperthyroidism compared to euthyroidism, and to describe factors associated with these responses. A standard-dose (0.25 mg/i.v.) ACTH stimulation test was performed to the same patients before hyperthyroidism treatment, and after attainment of euthyroidism. Baseline cortisol (Cor(0)), DHEA-S (DHEA-S(0)), cortisol binding globulin (CBG), ACTH, calculated free cortisol (by Coolen's equation = CFC), free cortisol index (FCI), 60-min cortisol (Cor(60)), and DHEA-S (DHEA-S(60)), delta cortisol (ΔCor), delta DHEA-S (ΔDHEA-S) responses were evaluated. Forty-one patients [22 females, 49.5 ± 15.2 years old, 32 Graves disease, nine toxic nodular goiter] had similar Cor(0), DHEA-S(0), CFC, FCI, and DHEA-S(60) in hyperthyroid and euthyroid states. Cor(60), ΔCor, and ΔDHEA-S were lower in hyperthyroidism. In four (10 %) patients the peak ACTH-stimulated cortisol values were lower than 18 μg/dL. When the test repeated after attainment of euthyroidism, all of the patients had normal cortisol response. Regression analysis demonstrated an independent association of Cor(60) with free T3 in hyperthyroidism. However, the predictors of CFC, FCI, and DHEA-S levels were serum creatinine levels in hyperthyroidism, and both creatinine and transaminase levels in euthyroidism. ACTH-stimulated peak cortisol, delta cortisol, and delta DHEA-S levels are decreased during hyperthyroidism, probably due to increased turnover. Since about 10 % of the subjects with hyperthyroidism are at risk for adrenal insufficiency, clinicians dealing with Graves' disease should be alert to the possibility of adrenal insufficiency during hyperthyroid stage.

  6. Reliability Generalization: "Lapsus Linguae"

    Smith, Julie M.


    This study examines the proposed Reliability Generalization (RG) method for studying reliability. RG employs the application of meta-analytic techniques similar to those used in validity generalization studies to examine reliability coefficients. This study explains why RG does not provide a proper research method for the study of reliability,…

  7. Global Reserve Cooperation


    St ra te gy R es ea rc h Pr oj ec t GLOBAL RESERVE COOPERATION BY LIEUTENANT COLONEL PAMELA L. MCGAHA United States Army National Guard...DATES COVERED (From - To) 4. TITLE AND SUBTITLE Global Reserve Cooperation 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...decade, the United States, its allies, and partner nations have greatly increased their reliance on Reserve Component forces. This global

  8. Reliability evaluation for offshore wind farms

    Zhao, Menghua; Blåbjerg, Frede; Chen, Zhe


    In this paper, a new reliability index - Loss Of Generation Ratio Probability (LOGRP) is proposed for evaluating the reliability of an electrical system for offshore wind farms, which emphasizes the design of wind farms rather than the adequacy for specific load demand. A practical method...... to calculate LOGRP of offshore wind farms is proposed and evaluated....

  9. Novel approach for evaluation of service reliability for electricity customers

    JIANG; John; N


    Understanding reliability value for electricity customer is important to market-based reliability management. This paper proposes a novel approach to evaluate the reliability for electricity customers by using indifference curve between economic compensation for power interruption and service reliability of electricity. Indifference curve is formed by calculating different planning schemes of network expansion for different reliability requirements of customers, which reveals the information about economic values for different reliability levels for electricity customers, so that the reliability based on market supply demand mechanism can be established and economic signals can be provided for reliability management and enhancement.

  10. Novel approach for evaluation of service reliability for electricity customers

    KANG ChongQing; GAO Yan; JIANG John N; ZHONG Jin; XIA Qing


    Understanding reliability value for electricity customer is important to market-based reliability man-agement. This paper proposes a novel approach to evaluate the reliability for electricity customers by using indifference curve between economic compensation for power interruption and service reliability of electricity. Indifference curve is formed by calculating different planning schemes of network ex-pansion for different reliability requirements of customers, which reveals the information about eco-nomic values for different reliability levels for electricity customers, so that the reliability based on market supply demand mechanism can be established and economic signals can be provided for reli-ability management and enhancement.

  11. Telecommunications system reliability engineering theory and practice

    Ayers, Mark L


    "Increasing system complexity require new, more sophisticated tools for system modeling and metric calculation. Bringing the field up to date, this book provides telecommunications engineers with practical tools for analyzing, calculating, and reporting availability, reliability, and maintainability metrics. It gives the background in system reliability theory and covers in-depth applications in fiber optic networks, microwave networks, satellite networks, power systems, and facilities management. Computer programming tools for simulating the approaches presented, using the Matlab software suite, are also provided"

  12. The impact of reliability on the productivity of railroad companies

    Abate, Megersa Abera; Lijesen, Mark; Pels, Eric


    This paper studies the relationship between reliability (proxied by punctuality) and productivity in passenger railroad services. Increasing reliability may lower productivity, as it requires inputs, that can’t be used to produce outputs. The relationship between reliability and productivity also...... the productivity of railway operations and aiming to improve both may be a feasible strategy. © 2013 Elsevier Ltd. All rights reserved....

  13. Ovarian reserve parameters

    Bentzen, J G; Forman, Julie Lyng; Pinborg, Anja;


    was observed between duration of hormonal-contraception use and ovarian reserve parameters. No dose-response relation was found between the dose of ethinyloestradiol and AMH or AFC. This study indicates that ovarian reserve markers are lower in women using sex steroids for contraception. Thus, AMH...

  14. Forex Reserve Puzzle


    China faces pressure of preserving the value of its $3 trillion foreign exchange reserves While already under pressure to revalue its currency,the yuan,against the U.S.dollar,China also faces the challenge of stifling vast losses to its foreign exchange reserve,mostly denominated in U.S.dollars.These losses to foreign exchange

  15. Blueprint for Energy Reserves

    Hao Zhenying


    @@ The government is drafting a strategic reserve blueprint to ensure energy security-the move coming close on the heels of the construction of four oil reserve bases, according to Ma Fucai, deputy director of the Office of the National Energy Leading Group.

  16. Estimation of Reserves of Tula Horizon Oil Deposits of Severo-Yurmanskoye Field, Perm Kray

    V I Nabiullin


    Full Text Available This article presents an estimation of reserves of the Tula horizon oil-bearing layers Tl2-a and Tl2-b at the Severo-Yurmanskoye oil field. Research was carried out in order to prospect the unestimated oil reserves at the previously drilled but not commercially producing areas of Perm kray. The opportunity of reserve calculation for this oil field was provided by the sufficient oil encroachment rate achieved during testing of Tula horizon layers in the borehole 174, reliable mapping of oil-bearing horizons using seismic and borehole data, existence of updated stratigraphic information, results of study of uniformity of oil-bearing layers throughout the area of the Severo-Yurmanskoye oil field, reliable estimate of the position of water-oil contact, defining the effective oil-bearing thickness of oil-bearing layers using results of borehole geophysical survey, study of lithological composition and reservoir  properties, study of physical and chemical properties of oil in borehole and in laboratory, and reliability of statistical evaluation of oil recovery factor.

  17. The biologically equivalent dose BED - Is the approach for calculation of this factor really a reliable basis?; Die biologisch aequivalente Dosis BED - wie solide ist die Berechnung dieses Faktors? Eine Betrachtung der Fehlerbalken der biologisch aequivalenten Dosis

    Jensen, J.M. [Kiel Univ. (DE). Klinik fuer Strahlentherapie (Radioonkologie); Zimmermann, J. [Marburg Univ. (DE). Klinik fuer Strahlentherapie (Radioonkologie)


    To predict the effect on tumours in radiotherapy, especially relating to irreversible effects, but also to realize the retrospective assessment the so called L-Q-model is relied on at present. Internal specific organ parameters, such as {alpha}, {beta}, {gamma}, T{sub p}, T{sub k}, and {rho}, as well as external parameters, so as D, d, n, V, and V{sub ref}, were used for determination of the biologically equivalent dose BED. While the external parameters are determinable with small deviations, the internal parameters depend on biological varieties and dispersons: In some cases the lowest value is assumed to be {delta}={+-}25%. This margin of error goes on to the biologically equivalent dose by means of the principle of superposition of errors. In some selected cases (lung, kidney, skin, rectum) these margins of error were calculated exemplarily. The input errors especially of the internal parameters cause a mean error {delta} on the biologically equivalent dose and a dispersion of the single fraction dose d dependent on the organ taking into consideration, of approximately 8-30%. Hence it follows only a very critical and cautious application of those L-Q-algorithms in expert proceedings, and in radiotherapy more experienced based decisions are recommended, instead of acting only upon simple two-dimensional mechanistic ideas. (orig.) [German] Um bei der Strahlentherapie von Tumoren die Wirkung, vor allem hinsichtlich irreversibler Effekte, zu prognostizieren, aber auch retrospektive Beurteilungen durchzufuehren, wird z.Z. auf das sog. LQ-Modell vertraut. Interne organspezifische Parameter, {alpha}, {beta}, {gamma}, T{sub p}, T{sub k} und {rho}, und externe Parameter, wie D, d, n, V und V{sub ref}, (Erlaeuterungen im Text) werden zur Bestimmung einer biologisch aequivalenten Dosis BED herangezogen. Waehrend die externen Parameter mit geringem Fehler bestimmbar sind, unterliegen die internen Parameter biologischen Varianzen und Streuungen, in manchen Faellen ist der

  18. Assuring reliability program effectiveness.

    Ball, L. W.


    An attempt is made to provide simple identification and description of techniques that have proved to be most useful either in developing a new product or in improving reliability of an established product. The first reliability task is obtaining and organizing parts failure rate data. Other tasks are parts screening, tabulation of general failure rates, preventive maintenance, prediction of new product reliability, and statistical demonstration of achieved reliability. Five principal tasks for improving reliability involve the physics of failure research, derating of internal stresses, control of external stresses, functional redundancy, and failure effects control. A final task is the training and motivation of reliability specialist engineers.

  19. The Accelerator Reliability Forum

    Lüdeke, Andreas; Giachino, R


    A high reliability is a very important goal for most particle accelerators. The biennial Accelerator Reliability Workshop covers topics related to the design and operation of particle accelerators with a high reliability. In order to optimize the over-all reliability of an accelerator one needs to gather information on the reliability of many different subsystems. While a biennial workshop can serve as a platform for the exchange of such information, the authors aimed to provide a further channel to allow for a more timely communication: the Particle Accelerator Reliability Forum [1]. This contribution will describe the forum and advertise it’s usage in the community.

  20. Reliability of plantar pressure platforms.

    Hafer, Jocelyn F; Lenhoff, Mark W; Song, Jinsup; Jordan, Joanne M; Hannan, Marian T; Hillstrom, Howard J


    Plantar pressure measurement is common practice in many research and clinical protocols. While the accuracy of some plantar pressure measuring devices and methods for ensuring consistency in data collection on plantar pressure measuring devices have been reported, the reliability of different devices when testing the same individuals is not known. This study calculated intra-mat, intra-manufacturer, and inter-manufacturer reliability of plantar pressure parameters as well as the number of plantar pressure trials needed to reach a stable estimate of the mean for an individual. Twenty-two healthy adults completed ten walking trials across each of two Novel emed-x(®) and two Tekscan MatScan(®) plantar pressure measuring devices in a single visit. Intraclass correlation (ICC) was used to describe the agreement between values measured by different devices. All intra-platform reliability correlations were greater than 0.70. All inter-emed-x(®) reliability correlations were greater than 0.70. Inter-MatScan(®) reliability correlations were greater than 0.70 in 31 and 52 of 56 parameters when looking at a 10-trial average and a 5-trial average, respectively. Inter-manufacturer reliability including all four devices was greater than 0.70 for 52 and 56 of 56 parameters when looking at a 10-trial average and a 5-trial average, respectively. All parameters reached a value within 90% of an unbiased estimate of the mean within five trials. Overall, reliability results are encouraging for investigators and clinicians who may have plantar pressure data sets that include data collected on different devices.

  1. Enlightenment on Computer Network Reliability From Transportation Network Reliability

    Hu Wenjun; Zhou Xizhao


    Referring to transportation network reliability problem, five new computer network reliability definitions are proposed and discussed. They are computer network connectivity reliability, computer network time reliability, computer network capacity reliability, computer network behavior reliability and computer network potential reliability. Finally strategies are suggested to enhance network reliability.

  2. Human Reliability Program Overview

    Bodin, Michael


    This presentation covers the high points of the Human Reliability Program, including certification/decertification, critical positions, due process, organizational structure, program components, personnel security, an overview of the US DOE reliability program, retirees and academia, and security program integration.

  3. Interpretation of Biosphere Reserves.

    Merriman, Tim


    Introduces the Man and the Biosphere Programme (MAB) to monitor the 193 biogeographical provinces of the Earth and the creation of biosphere reserves. Highlights the need for interpreters to become familiar or involved with MAB program activities. (LZ)

  4. Professor reveals darter reserve

    US Fish and Wildlife Service, Department of the Interior — Newspaper article on on reserve population of watercress darter in Pinson, AL to help save the population in Roebuck Spring after a significant fish kill in 2008.

  5. Exact reliability quantification of highly reliable systems with maintenance

    Bris, Radim, E-mail: radim.bris@vsb.c [VSB-Technical University Ostrava, Faculty of Electrical Engineering and Computer Science, Department of Applied Mathematics, 17. listopadu 15, 70833 Ostrava-Poruba (Czech Republic)


    When a system is composed of highly reliable elements, exact reliability quantification may be problematic, because computer accuracy is limited. Inaccuracy can be due to different aspects. For example, an error may be made when subtracting two numbers that are very close to each other, or at the process of summation of many very different numbers, etc. The basic objective of this paper is to find a procedure, which eliminates errors made by PC when calculations close to an error limit are executed. Highly reliable system is represented by the use of directed acyclic graph which is composed from terminal nodes, i.e. highly reliable input elements, internal nodes representing subsystems and edges that bind all of these nodes. Three admissible unavailability models of terminal nodes are introduced, including both corrective and preventive maintenance. The algorithm for exact unavailability calculation of terminal nodes is based on merits of a high-performance language for technical computing MATLAB. System unavailability quantification procedure applied to a graph structure, which considers both independent and dependent (i.e. repeatedly occurring) terminal nodes is based on combinatorial principle. This principle requires summation of a lot of very different non-negative numbers, which may be a source of an inaccuracy. That is why another algorithm for exact summation of such numbers is designed in the paper. The summation procedure uses benefits from a special number system with the base represented by the value 2{sup 32}. Computational efficiency of the new computing methodology is compared with advanced simulation software. Various calculations on systems from references are performed to emphasize merits of the methodology.

  6. Reliable Design Versus Trust

    Berg, Melanie; LaBel, Kenneth A.


    This presentation focuses on reliability and trust for the users portion of the FPGA design flow. It is assumed that the manufacturer prior to hand-off to the user tests FPGA internal components. The objective is to present the challenges of creating reliable and trusted designs. The following will be addressed: What makes a design vulnerable to functional flaws (reliability) or attackers (trust)? What are the challenges for verifying a reliable design versus a trusted design?

  7. Viking Lander reliability program

    Pilny, M. J.


    The Viking Lander reliability program is reviewed with attention given to the development of the reliability program requirements, reliability program management, documents evaluation, failure modes evaluation, production variation control, failure reporting and correction, and the parts program. Lander hardware failures which have occurred during the mission are listed.

  8. Combination of structural reliability and interval analysis

    Zhiping Qiu; Di Yang; saac Elishakoff


    In engineering applications,probabilistic reliability theory appears to be presently the most important method,however,in many cases precise probabilistic reliability theory cannot be considered as adequate and credible model of the real state of actual affairs.In this paper,we developed a hybrid of probabilistic and non-probabilistic reliability theory,which describes the structural uncertain parameters as interval variables when statistical data are found insufficient.By using the interval analysis,a new method for calculating the interval of the structural reliability as well as the reliability index is introduced in this paper,and the traditional probabilistic theory is incorporated with the interval analysis.Moreover,the new method preserves the useful part of the traditional probabilistic reliability theory,but removes the restriction of its strict requirement on data acquisition.Example is presented to demonstrate the feasibility and validity of the proposed theory.

  9. Is quantitative electromyography reliable?

    Cecere, F; Ruf, S; Pancherz, H


    The reliability of quantitative electromyography (EMG) of the masticatory muscles was investigated in 14 subjects without any signs or symptoms of temporomandibular disorders. Integrated EMG activity from the anterior temporalis and masseter muscles was recorded bilaterally by means of bipolar surface electrodes during chewing and biting activities. In the first experiment, the influence of electrode relocation was investigated. No influence of electrode relocation on the recorded EMG signal could be detected. In a second experiment, three sessions of EMG recordings during five different chewing and biting activities were performed in the morning (I); 1 hour later without intermediate removal of the electrodes (II); and in the afternoon, using new electrodes (III). The method errors for different time intervals (I-II and I-III errors) for each muscle and each function were calculated. Depending on the time interval between the EMG recordings, the muscles considered, and the function performed, the individual errors ranged from 5% to 63%. The method error increased significantly (P masseter (mean 27.2%) was higher than for the temporalis (mean 20.0%). The largest function error was found during maximal biting in intercuspal position (mean 23.1%). Based on the findings, quantitative electromyography of the masticatory muscles seems to have a limited value in diagnostics and in the evaluation of individual treatment results.

  10. Real-time reliability evaluation methodology based on dynamic Bayesian networks: A case study of a subsea pipe ram BOP system.

    Cai, Baoping; Liu, Yonghong; Ma, Yunpeng; Liu, Zengkai; Zhou, Yuming; Sun, Junhe


    A novel real-time reliability evaluation methodology is proposed by combining root cause diagnosis phase based on Bayesian networks (BNs) and reliability evaluation phase based on dynamic BNs (DBNs). The root cause diagnosis phase exactly locates the root cause of a complex mechatronic system failure in real time to increase diagnostic coverage and is performed through backward analysis of BNs. The reliability evaluation phase calculates the real-time reliability of the entire system by forward inference of DBNs. The application of the proposed methodology is demonstrated using a case of a subsea pipe ram blowout preventer system. The value and the variation trend of real-time system reliability when the faults of components occur are studied; the importance degree sequence of components at different times is also determined using mutual information and belief variance. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  11. Biomarkers of Ovarian Reserve

    William E. Roudebush


    Full Text Available The primary function of the female ovary is the production of a mature and viable oocyte capable of fertilization and subsequent embryo development and implantation. At birth, the ovary contains a finite number of oocytes available for folliculogenesis. This finite number of available oocytes is termed “the ovarian reserve”. The determination of ovarian reserve is important in the assessment and treatment of infertility. As the ovary ages, the ovarian reserve will decline. Infertility affects approximately 15-20% of reproductive aged couples. The most commonly used biomarker assay to assess ovarian reserve is the measurement of follicle stimulating hormone (FSH on day 3 of the menstrual cycle. However, antimüllerian hormone and inhibin-B are other biomarkers of ovarian reserve that are gaining in popularity since they provide direct determination of ovarian status, whereas day 3 FSH is an indirect measurement. This review examines the physical tools and the hormone biomarkers used to evaluate ovarian reserve.

  12. Reliability design method for steam turbine blades

    Jinyuan SHI


    Based on theories of probability and statistics, and taking static stresses, dynamic stresses, endurance strength, safety ratios, vibration frequencies and exciting force frequencies of blades as random variables, a reliabil-ity design method for steam turbine blades is presented. The purport and calculation method for blade reliability are expounded. The distribution parameters of random variables are determined after analysis and numerical cal-culation of test data. The fatigue strength and the vibra-tion design reliability of turbine blades are determined with the aid of a probabilistic design method and by inter-ference models for stress distribution and strength distri-bution. Some blade reliability design calculation formulas for a dynamic stress design method, a safety ratio design method for fatigue strength, and a vibration reliability design method for the first and second types of tuned blades and a packet of blades on a disk connected closely, are given together with some practical examples. With these methods, the design reliability of steam turbine blades can be guaranteed in the design stage. This research may provide some scientific basis for reliability design of steam turbine blades.


    彭世济; 张达贤; 习永峰; 卢明银; 孙洪泉


    The method of reliability analysis of mineral reserve estimation, mining construction, mining technological system and surface mine investment in mine design is discussed in this paper. On the basis of this method, the questions, such as "whether the planned production and predicted economic effectiveness could be obtained", can be answered, and corresponding measures can be taken.

  14. Methodology for Selection of Non-Restored Reserved Systems Pertaining to Control of Technological Processes

    V. A. Anischenko


    Full Text Available The paper contains analysis of reliability of non-restored passive reserved systems pertaining to control of technological processes. Criteria have been justified and methodology for optimum selection of reserved systems has been developed.

  15. School Shootings Stun Reservation

    Borja, Rhea R.; Cavanagh, Sean


    This article deals with the impact brought by the school shootings at Red Lake Indian Reservation in Minnesota to the school community. A deeply troubled 16-year-old student shot and killed seven other people and himself at a high school. The nation's deadliest school attack since the 1999 slayings at Colorado's suburban Columbine High School took…

  16. Reliability and safety engineering

    Verma, Ajit Kumar; Karanki, Durga Rao


    Reliability and safety are core issues that must be addressed throughout the life cycle of engineering systems. Reliability and Safety Engineering presents an overview of the basic concepts, together with simple and practical illustrations. The authors present reliability terminology in various engineering fields, viz.,electronics engineering, software engineering, mechanical engineering, structural engineering and power systems engineering. The book describes the latest applications in the area of probabilistic safety assessment, such as technical specification optimization, risk monitoring and risk informed in-service inspection. Reliability and safety studies must, inevitably, deal with uncertainty, so the book includes uncertainty propagation methods: Monte Carlo simulation, fuzzy arithmetic, Dempster-Shafer theory and probability bounds. Reliability and Safety Engineering also highlights advances in system reliability and safety assessment including dynamic system modeling and uncertainty management. Cas...

  17. Measurement System Reliability Assessment

    Kłos Ryszard


    Full Text Available Decision-making in problem situations is based on up-to-date and reliable information. A great deal of information is subject to rapid changes, hence it may be outdated or manipulated and enforce erroneous decisions. It is crucial to have the possibility to assess the obtained information. In order to ensure its reliability it is best to obtain it with an own measurement process. In such a case, conducting assessment of measurement system reliability seems to be crucial. The article describes general approach to assessing reliability of measurement systems.

  18. Reliable knowledge discovery

    Dai, Honghua; Smirnov, Evgueni


    Reliable Knowledge Discovery focuses on theory, methods, and techniques for RKDD, a new sub-field of KDD. It studies the theory and methods to assure the reliability and trustworthiness of discovered knowledge and to maintain the stability and consistency of knowledge discovery processes. RKDD has a broad spectrum of applications, especially in critical domains like medicine, finance, and military. Reliable Knowledge Discovery also presents methods and techniques for designing robust knowledge-discovery processes. Approaches to assessing the reliability of the discovered knowledge are introduc

  19. Circuit design for reliability

    Cao, Yu; Wirth, Gilson


    This book presents physical understanding, modeling and simulation, on-chip characterization, layout solutions, and design techniques that are effective to enhance the reliability of various circuit units.  The authors provide readers with techniques for state of the art and future technologies, ranging from technology modeling, fault detection and analysis, circuit hardening, and reliability management. Provides comprehensive review on various reliability mechanisms at sub-45nm nodes; Describes practical modeling and characterization techniques for reliability; Includes thorough presentation of robust design techniques for major VLSI design units; Promotes physical understanding with first-principle simulations.

  20. Calculator calculus

    McCarty, George


    How THIS BOOK DIFFERS This book is about the calculus. What distinguishes it, however, from other books is that it uses the pocket calculator to illustrate the theory. A computation that requires hours of labor when done by hand with tables is quite inappropriate as an example or exercise in a beginning calculus course. But that same computation can become a delicate illustration of the theory when the student does it in seconds on his calculator. t Furthermore, the student's own personal involvement and easy accomplishment give hi~ reassurance and en­ couragement. The machine is like a microscope, and its magnification is a hundred millionfold. We shall be interested in limits, and no stage of numerical approximation proves anything about the limit. However, the derivative of fex) = 67.SgX, for instance, acquires real meaning when a student first appreciates its values as numbers, as limits of 10 100 1000 t A quick example is 1.1 , 1.01 , 1.001 , •••• Another example is t = 0.1, 0.01, in the functio...

  1. Algorithm of communication network reliability combining links, nodes and capacity


    The conception of the normalized reliability index weighted by capacity is introduced, which combing the communication capacity, the reliability probability of exchange nodes and the reliability probability of the transmission links,in order to estimate the reliability performance of communication network comprehensively and objectively. To realize the full algebraic calculation, the key problem should be resolved, which is to find an algorithm to calculate all the routes between nodes of a network. A kind of logic algebraic algorithm of network routes is studied and based on this algorithm,the full algebraic algorithm of normalized reliability index weighted by capacity is studied. For this algorithm, it is easy to design program and the calculation of reliability index is finished, which is the foundation of the comprehensive and objective estimation of comnunication networks. The calculation procedure of the algorithm is introduced through typical ex amples and the results verify the algorithm.

  2. Assessment of the Reliability Profiles for Concrete Bridges

    Thoft-Christensen, Palle

    In this paper calculation of reliability profiles is discussed. ULS as well as SLS limit states are formulated. Corrosion due to chloride penetration is the considered deterioration mechanism. Three models for corrosion are formulated. A definition of service lifetime for concrete bridges...... is presented and discussed. The proposed method of calculating reliability profiles is illustrated on an exiting U.K. bridge....

  3. Reliability of Arctic offshore installations

    Bercha, F.G. [Bercha Group, Calgary, AB (Canada); Gudmestad, O.T. [Stavanger Univ., Stavanger (Norway)]|[Statoil, Stavanger (Norway)]|[Norwegian Univ. of Technology, Stavanger (Norway); Foschi, R. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Civil Engineering; Sliggers, F. [Shell International Exploration and Production, Rijswijk (Netherlands); Nikitina, N. [VNIIG, St. Petersburg (Russian Federation); Nevel, D.


    Life threatening and fatal failures of offshore structures can be attributed to a broad range of causes such as fires and explosions, buoyancy losses, and structural overloads. This paper addressed the different severities of failure types, categorized as catastrophic failure, local failure or serviceability failure. Offshore tragedies were also highlighted, namely the failures of P-36, the Ocean Ranger, the Piper Alpha, and the Alexander Kieland which all resulted in losses of human life. P-36 and the Ocean Ranger both failed ultimately due to a loss of buoyancy. The Piper Alpha was destroyed by a natural gas fire, while the Alexander Kieland failed due to fatigue induced structural failure. The mode of failure was described as being the specific way in which a failure occurs from a given cause. Current reliability measures in the context of offshore installations only consider the limited number of causes such as environmental loads. However, it was emphasized that a realistic value of the catastrophic failure probability should consider all credible causes of failure. This paper presented a general method for evaluating all credible causes of failure of an installation. The approach to calculating integrated reliability involves the use of network methods such as fault trees to combine the probabilities of all factors that can cause a catastrophic failure, as well as those which can cause a local failure with the potential to escalate to a catastrophic failure. This paper also proposed a protocol for setting credible reliability targets such as the consideration of life safety targets and escape, evacuation, and rescue (EER) success probabilities. A set of realistic reliability targets for both catastrophic and local failures for representative safety and consequence categories associated with offshore installations was also presented. The reliability targets were expressed as maximum average annual failure probabilities. The method for converting these annual

  4. Poor ovarian reserve

    Padma Rekha Jirge


    Full Text Available Poor ovarian reserve (POR is an important limiting factor for the success of any treatment modality for infertility. It indicates a reduction in quantity and quality of oocytes in women of reproductive age group. It may be age related as seen in advanced years of reproductive life or may occur in young women due to diverse etiological factors. Evaluating ovarian reserve and individualizing the therapeutic strategies are very important for optimizing the success rate. Majority or women with POR need to undergo in vitro fertilization to achieve pregnancy. However, pregnancy rate remains low despite a plethora of interventions and is associated with high pregnancy loss. Early detection and active management are essential to minimize the need for egg donation in these women.

  5. On the reliability of Seasonal Climate Forecasts

    Weisheimer, Antje


    Seasonal climate forecasts are being used increasingly across a range of application sectors. A recent UK governmental report asked: How good are seasonal climate forecasts on a scale of 1-5 (where 5 is very good), and how good can we expect them to be in 30 years time? Seasonal climate forecasts are made from ensembles of integrations of numerical models of climate. We argue that goodness should be assessed primarily in terms of the probabilistic reliability of these ensemble-based forecasts and that a 5 should be reserved for systems which are not only reliable overall, but where, in particular, small ensemble spread is a reliable indicator of low ensemble forecast error. We study the reliability of regional temperature and precipitation forecasts of the current operational seasonal forecast system of the European Centre for Medium-Range Weather Forecasts, universally regarded as a world leading operational institute producing seasonal climate forecasts. A wide range of goodness rankings, depending on regio...

  6. LED system reliability

    Driel, W.D. van; Yuan, C.A.; Koh, S.; Zhang, G.Q.


    This paper presents our effort to predict the system reliability of Solid State Lighting (SSL) applications. A SSL system is composed of a LED engine with micro-electronic driver(s) that supplies power to the optic design. Knowledge of system level reliability is not only a challenging scientific ex

  7. Principles of Bridge Reliability

    Thoft-Christensen, Palle; Nowak, Andrzej S.

    The paper gives a brief introduction to the basic principles of structural reliability theory and its application to bridge engineering. Fundamental concepts like failure probability and reliability index are introduced. Ultimate as well as serviceability limit states for bridges are formulated...

  8. Improving machinery reliability

    Bloch, Heinz P


    This totally revised, updated and expanded edition provides proven techniques and procedures that extend machinery life, reduce maintenance costs, and achieve optimum machinery reliability. This essential text clearly describes the reliability improvement and failure avoidance steps practiced by best-of-class process plants in the U.S. and Europe.

  9. Scaled CMOS Technology Reliability Users Guide

    White, Mark


    The desire to assess the reliability of emerging scaled microelectronics technologies through faster reliability trials and more accurate acceleration models is the precursor for further research and experimentation in this relevant field. The effect of semiconductor scaling on microelectronics product reliability is an important aspect to the high reliability application user. From the perspective of a customer or user, who in many cases must deal with very limited, if any, manufacturer's reliability data to assess the product for a highly-reliable application, product-level testing is critical in the characterization and reliability assessment of advanced nanometer semiconductor scaling effects on microelectronics reliability. A methodology on how to accomplish this and techniques for deriving the expected product-level reliability on commercial memory products are provided.Competing mechanism theory and the multiple failure mechanism model are applied to the experimental results of scaled SDRAM products. Accelerated stress testing at multiple conditions is applied at the product level of several scaled memory products to assess the performance degradation and product reliability. Acceleration models are derived for each case. For several scaled SDRAM products, retention time degradation is studied and two distinct soft error populations are observed with each technology generation: early breakdown, characterized by randomly distributed weak bits with Weibull slope (beta)=1, and a main population breakdown with an increasing failure rate. Retention time soft error rates are calculated and a multiple failure mechanism acceleration model with parameters is derived for each technology. Defect densities are calculated and reflect a decreasing trend in the percentage of random defective bits for each successive product generation. A normalized soft error failure rate of the memory data retention time in FIT/Gb and FIT/cm2 for several scaled SDRAM generations is

  10. Payment of Interest on Reserves

    Weiner, Stuart E


    .... These reserve requirements, in conjunction with control over the reserve supply, effectively place an upper limit on deposit creation and thus help the Federal Reserve System control the growth of money...

  11. Chapter 9: Reliability

    Algora, Carlos; Espinet-Gonzalez, Pilar; Vazquez, Manuel; Bosco, Nick; Miller, David; Kurtz, Sarah; Rubio, Francisca; McConnell,Robert


    This chapter describes the accumulated knowledge on CPV reliability with its fundamentals and qualification. It explains the reliability of solar cells, modules (including optics) and plants. The chapter discusses the statistical distributions, namely exponential, normal and Weibull. The reliability of solar cells includes: namely the issues in accelerated aging tests in CPV solar cells, types of failure and failures in real time operation. The chapter explores the accelerated life tests, namely qualitative life tests (mainly HALT) and quantitative accelerated life tests (QALT). It examines other well proven and experienced PV cells and/or semiconductor devices, which share similar semiconductor materials, manufacturing techniques or operating conditions, namely, III-V space solar cells and light emitting diodes (LEDs). It addresses each of the identified reliability issues and presents the current state of the art knowledge for their testing and evaluation. Finally, the chapter summarizes the CPV qualification and reliability standards.

  12. The stability safety factor calibration based on the reliability index

    Tong Xiaolong; Fang Zhi


    When the bridge structure stability safety factor of the first type is 4,the research that whether the structure reliability index will reach target reliability index under the more-likely-to-happen collapse situation of the second type is necessary. The stability calculations of the first and the second type are made respectively for single layer and single span rigid frame bridge. Based on the critical load obtained from the stability calculation of the first type,the stability safety factor of the first type is taken as 4,and the first order reliability method is used to program and calculate the reliability index. Then,the load effect under the stability reliability index cal-culation of the first type and the critical load of the second type are employed to calculate the reliability index of the second type. The evaluation of structure stability safety factor is discussed according to reliability index. Based on the discussion above,parameter analysis of the stable critical loads of two types is made,and the in-fluence of critical load change on reliability index is researched. The result shows that stability analysis should identify collapse state;when the stability safety factor of the first type is 4,but the structure has the collapse of the second type,the reliability index cannot be ensured to reach the target reliability index under certain condi-tions.

  13. 77 FR 66361 - Reserve Requirements of Depository Institutions: Reserves Simplification


    ... AD 83 Reserve Requirements of Depository Institutions: Reserves Simplification AGENCY: Board of... Regulation D (Reserve Requirements of Depository Institutions) published in the Federal Register on April 12... simplifications related to the administration of reserve requirements: 1. Create a common two-week...

  14. A Novel TRM Calculation Method by Probabilistic Concept

    Audomvongseree, Kulyos; Yokoyama, Akihiko; Verma, Suresh Chand; Nakachi, Yoshiki

    In a new competitive environment, it becomes possible for the third party to access a transmission facility. From this structure, to efficiently manage the utilization of the transmission network, a new definition about Available Transfer Capability (ATC) has been proposed. According to the North American ElectricReliability Council (NERC)’s definition, ATC depends on several parameters, i. e. Total Transfer Capability (TTC), Transmission Reliability Margin (TRM), and Capacity Benefit Margin (CBM). This paper is focused on the calculation of TRM which is one of the security margin reserved for any uncertainty of system conditions. The TRM calculation by probabilistic method is proposed in this paper. Based on the modeling of load forecast error and error in transmission line limitation, various cases of transmission transfer capability and its related probabilistic nature can be calculated. By consideration of the proposed concept of risk analysis, the appropriate required amount of TRM can be obtained. The objective of this research is to provide realistic information on the actual ability of the network which may be an alternative choice for system operators to make an appropriate decision in the competitive market. The advantages of the proposed method are illustrated by application to the IEEJ-WEST10 model system.

  15. Fractional Reserve Banking

    Andreasen, Niels; Bjerregaard, Mads; Lund, Jonas; Olsen, Ove Bitsch; Rasmussen, Andreas Dalgas


    Projektet er bygget op omkring kritisk realisme, som er det gennemgående videnskabelige fundament til undersøgelsen af hvilke strukturelle grunde der er til finansiel ustabilitet i Danmark. Projektet går i dybden med Fractional Reserve Banking og incitamentsstrukturen i banksystemet. Vi bevæger os både på det makro- og mikroøkonomiske niveau i analysen. På makro niveau bruger vi den østrigske skole om konjunktur teori (The Positive Theory of the Cycle). På mikro niveau arbejder vi med princip...

  16. Fractional Reserve Banking

    Andreasen, Niels; Bjerregaard, Mads; Lund, Jonas; Olsen, Ove Bitsch; Rasmussen, Andreas Dalgas


    Projektet er bygget op omkring kritisk realisme, som er det gennemgående videnskabelige fundament til undersøgelsen af hvilke strukturelle grunde der er til finansiel ustabilitet i Danmark. Projektet går i dybden med Fractional Reserve Banking og incitamentsstrukturen i banksystemet. Vi bevæger os både på det makro- og mikroøkonomiske niveau i analysen. På makro niveau bruger vi den østrigske skole om konjunktur teori (The Positive Theory of the Cycle). På mikro niveau arbejder vi med princip...

  17. Photovoltaic system reliability

    Maish, A.B.; Atcitty, C. [Sandia National Labs., NM (United States); Greenberg, D. [Ascension Technology, Inc., Lincoln Center, MA (United States)] [and others


    This paper discusses the reliability of several photovoltaic projects including SMUD`s PV Pioneer project, various projects monitored by Ascension Technology, and the Colorado Parks project. System times-to-failure range from 1 to 16 years, and maintenance costs range from 1 to 16 cents per kilowatt-hour. Factors contributing to the reliability of these systems are discussed, and practices are recommended that can be applied to future projects. This paper also discusses the methodology used to collect and analyze PV system reliability data.

  18. Structural Reliability Methods

    Ditlevsen, Ove Dalager; Madsen, H. O.

    of structural reliability, including the theoretical basis for these methods. Partial safety factor codes under current practice are briefly introduced and discussed. A probabilistic code format for obtaining a formal reliability evaluation system that catches the most essential features of the nature......The structural reliability methods quantitatively treat the uncertainty of predicting the behaviour and properties of a structure given the uncertain properties of its geometry, materials, and the actions it is supposed to withstand. This book addresses the probabilistic methods for evaluation...

  19. Reserves in western basins

    Caldwell, R.H.; Cotton, B.W. [Scotia Group, Dallas, TX (United States)


    The objective of this project is to investigate the reserves potential of tight gas reservoirs in three Rocky Mountain basins: the Greater Green River (GGRB), Uinta and Piceance basins. The basins contain vast gas resources that have been estimated in the thousands of Tcf hosted in low permeability clastic reservoirs. This study documents the productive characteristics of these tight reservoirs, requantifies gas in place resources, and characterizes the reserves potential of each basin. The purpose of this work is to promote understanding of the resource and to encourage its exploitation by private industry. At this point in time, the GGRB work has been completed and a final report published. Work is well underway in the Uinta and Piceance basins which are being handled concurrently, with reports on these basins being scheduled for the middle of this year. Since the GGRB portion of the project has been completed, this presentation win focus upon that basin. A key conclusion of this study was the subdivision of the resource, based upon economic and technological considerations, into groupings that have distinct properties with regard to potential for future producibility, economics and risk profile.

  20. Reliable Electronic Equipment

    N. A. Nayak


    Full Text Available The reliability aspect of electronic equipment's is discussed. To obtain optimum results, close cooperation between the components engineer, the design engineer and the production engineer is suggested.

  1. Reliability prediction techniques

    Whittaker, B.; Worthington, B.; Lord, J.F.; Pinkard, D.


    The paper demonstrates the feasibility of applying reliability assessment techniques to mining equipment. A number of techniques are identified and described and examples of their use in assessing mining equipment are given. These techniques include: reliability prediction; failure analysis; design audit; maintainability; availability and the life cycle costing. Specific conclusions regarding the usefulness of each technique are outlined. The choice of techniques depends upon both the type of equipment being assessed and its stage of development, with numerical prediction best suited for electronic equipment and fault analysis and design audit suited to mechanical equipment. Reliability assessments involve much detailed and time consuming work but it has been demonstrated that the resulting reliability improvements lead to savings in service costs which more than offset the cost of the evaluation.

  2. Calculating Cumulative Binomial-Distribution Probabilities

    Scheuer, Ernest M.; Bowerman, Paul N.


    Cumulative-binomial computer program, CUMBIN, one of set of three programs, calculates cumulative binomial probability distributions for arbitrary inputs. CUMBIN, NEWTONP (NPO-17556), and CROSSER (NPO-17557), used independently of one another. Reliabilities and availabilities of k-out-of-n systems analyzed. Used by statisticians and users of statistical procedures, test planners, designers, and numerical analysts. Used for calculations of reliability and availability. Program written in C.

  3. Reliability of power connections

    BRAUNOVIC Milenko


    Despite the use of various preventive maintenance measures, there are still a number of problem areas that can adversely affect system reliability. Also, economical constraints have pushed the designs of power connections closer to the limits allowed by the existing standards. The major parameters influencing the reliability and life of Al-Al and Al-Cu connections are identified. The effectiveness of various palliative measures is determined and the misconceptions about their effectiveness are dealt in detail.

  4. The stability safety factor calibration pased on the reliability index

    Tong Xiaolong; Fang Zhi


    When the bridge structure stability safety factor of the first type is 4, the research that whether the structure reliability index will reach target reliability index under the more-likely-to-happen collapse situation of the second type is necessary. The stability calculations of the first and the second type are made respectively for single layer and single span rigid frame bridge. Based on the critical load obtained from the stability calculation of the first type, the stability safety factor of the first type is taken as 4, and the first order reliability method is used to program and calculate the reliability index. Then, the load effect under the stability reliability index cal- culation of the first type and the critical load of the second type are employed to calculate the reliability index of the second type. The evaluation of structure stability safety factor is discussed according to reliability index. Based on the discussion above, parameter analysis of the stable critical loads of two types is made, and the in- fluence of critical load change on reliability index is researched. The result shows that stability analysis should identify collapse state; when the stability safety factor of the first type is 4, but the structure has the collapse of the second type, the reliability index cannot be ensured to reach the target reliability index under certain condi- tions.

  5. Multidisciplinary System Reliability Analysis

    Mahadevan, Sankaran; Han, Song; Chamis, Christos C. (Technical Monitor)


    The objective of this study is to develop a new methodology for estimating the reliability of engineering systems that encompass multiple disciplines. The methodology is formulated in the context of the NESSUS probabilistic structural analysis code, developed under the leadership of NASA Glenn Research Center. The NESSUS code has been successfully applied to the reliability estimation of a variety of structural engineering systems. This study examines whether the features of NESSUS could be used to investigate the reliability of systems in other disciplines such as heat transfer, fluid mechanics, electrical circuits etc., without considerable programming effort specific to each discipline. In this study, the mechanical equivalence between system behavior models in different disciplines are investigated to achieve this objective. A new methodology is presented for the analysis of heat transfer, fluid flow, and electrical circuit problems using the structural analysis routines within NESSUS, by utilizing the equivalence between the computational quantities in different disciplines. This technique is integrated with the fast probability integration and system reliability techniques within the NESSUS code, to successfully compute the system reliability of multidisciplinary systems. Traditional as well as progressive failure analysis methods for system reliability estimation are demonstrated, through a numerical example of a heat exchanger system involving failure modes in structural, heat transfer and fluid flow disciplines.

  6. Sensitivity Analysis of Component Reliability



    In a system, Every component has its unique position within system and its unique failure characteristics. When a component's reliability is changed, its effect on system reliability is not equal. Component reliability sensitivity is a measure of effect on system reliability while a component's reliability is changed. In this paper, the definition and relative matrix of component reliability sensitivity is proposed, and some of their characteristics are analyzed. All these will help us to analyse or improve the system reliability.




    Full Text Available Reliability is the probability that a system, component or device will perform without failure for a specified period of time under specified operating conditions. The concept of reliability is of great importance in the design of various machine members. Conventional engineering design uses a deterministic approach. It disregards the fact that the material properties, the dimensions of the components and the externally applied loads are statistical in nature. In conventional design this uncertainties are covered with a factor of safety, which is not always successful. The growing trend towards reducing uncertainty and increasing reliability is to use the probabilistic approach. In the present work a three shaft four speed gear box and six speed gear box are designed using reliability principles. For the specified reliability of the system (Gear box, component reliability (Gear pair is calculated by considering the system as a series system. Design is considered to be safe and adequate if the probability of failure of gear box is less than or equal to a specified quantity in each of the two failure modes. . All the parameters affecting the design are considered as random variables and all the random variables are assumed to follow normal distribution. A computer program in C++ is developed to calculate the face widths in bending and surface failure modes. The larger one out of the two values is considered. By changing the variations in the design parameters, variations in the face widths are studied.

  8. Reliability Analysis of High Rockfill Dam Stability

    Ping Yi


    Full Text Available A program 3DSTAB combining slope stability analysis and reliability analysis is developed and validated. In this program, the limit equilibrium method is utilized to calculate safety factors of critical slip surfaces. The first-order reliability method is used to compute reliability indexes corresponding to critical probabilistic surfaces. When derivatives of the performance function are calculated by finite difference method, the previous iteration’s critical slip surface is saved and used. This sequential approximation strategy notably improves efficiency. Using this program, the stability reliability analyses of concrete faced rockfill dams and earth core rockfill dams with different heights and different slope ratios are performed. The results show that both safety factors and reliability indexes decrease as the dam’s slope increases at a constant height and as the dam’s height increases at a constant slope. They decrease dramatically as the dam height increases from 100 m to 200 m while they decrease slowly once the dam height exceeds 250 m, which deserves attention. Additionally, both safety factors and reliability indexes of the upstream slope of earth core rockfill dams are higher than that of the downstream slope. Thus, the downstream slope stability is the key failure mode for earth core rockfill dams.

  9. Estimating Quartz Reserves Using Compositional Kriging

    J. Taboada


    Full Text Available The aim of this study was to determine spatial distribution and volume of four commercial quartz grades, namely, silicon metal, ferrosilicon, aggregate, and kaolin (depending on content in impurities in a quartz seam. The chemical and mineralogical composition of the reserves in the seam were determined from samples collected from outcrops, blasting operations, and exploratory drilling, and compositional kriging was used to calculate the volume and distribution of the reserves. A more accurate knowledge of the deposit ensures better mine planning, leading to higher profitability and an improved relationship with the environment.

  10. How reliable is the Spanish bodily harm assessment scale?

    Ordóñez-Mayán, Lucía; Represas, Carlos; Miguéns, Xoan; Rodríguez-Calvo, María Sol; Febrero-Bande, Manuel; Muñoz-Barús, José Ignacio


    The use of scales to quantify or qualify bodily harm resulting from an unintentional car accident has been mandatory in Spain since 1995 and compensation for personal injuries resulting from a traffic accident is calculated according to a legal ruling established by Royal Decree 8/2004 (RDL). This present study assesses the reliability of the scale. Agreement between the evaluations for the same patient by 24 qualified observers following the Royal Decree 8/2004 was measured using the Kappa index. The variables assessed were the days of hospitalization, impeditive days, non impeditive days and the functional and aesthetic sequelae. The application of the Fleiss Kappa index obtained a result of 0.37, indicating a "fair agreement" according to the rating scale proposed by Landis and Koch. This study demonstrates the unreliability of the Spanish medical scale for the assessment of injury as described in the RDL 8/2004. The scale should adopt the measurement systems and clinical classifications of outcomes such as the ASIA, SCI scale or the Daniels scale of neurological injury and allow scientific discussion of the findings of the report. The resulting quantitative value should operate as a reliable indicator of a specific quality of the damage. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.


    韩金炎; 孙小彦; 彭世济


    The optimal decision theory and exploitation reliability of large scale mining area have heen studied in China since the late 1980′s. Researches have been carried out under the thought of mannature-machine system, and encouraging results have been obtained. The reliability evaluation of mining engineering includes the reliability evaluation of natural resources, mining technology and mine economics etc. And the geological reliability of deposit, as a natural condition, is the basis of all other evaluation works. The paper summarizes the method for evaluating the geological reliability of deposit, discusses the reliability of estimating methods for coal reserves and coal quality, evaluates the natural resources reliability of the Pit 1 of Antaibao, Surface Coal Mine, Pingsuo, Shanxi Province. which was taken as a case study.


    Тамаргазін, О. А.; Національний авіаційний університет; Власенко, П. О.; Національний авіаційний університет


    Airline's operational structure for Reliability program implementation — engineering division, reliability  division, reliability control division, aircraft maintenance division, quality assurance division — was considered. Airline's Reliability program structure is shown. Using of Reliability program for reducing costs on aircraft maintenance is proposed. Рассмотрена организационная структура авиакомпании по выполнению Программы надежности - инженерный отдел, отделы по надежности авиацио...

  13. Ultra reliability at NASA

    Shapiro, Andrew A.


    Ultra reliable systems are critical to NASA particularly as consideration is being given to extended lunar missions and manned missions to Mars. NASA has formulated a program designed to improve the reliability of NASA systems. The long term goal for the NASA ultra reliability is to ultimately improve NASA systems by an order of magnitude. The approach outlined in this presentation involves the steps used in developing a strategic plan to achieve the long term objective of ultra reliability. Consideration is given to: complex systems, hardware (including aircraft, aerospace craft and launch vehicles), software, human interactions, long life missions, infrastructure development, and cross cutting technologies. Several NASA-wide workshops have been held, identifying issues for reliability improvement and providing mitigation strategies for these issues. In addition to representation from all of the NASA centers, experts from government (NASA and non-NASA), universities and industry participated. Highlights of a strategic plan, which is being developed using the results from these workshops, will be presented.

  14. Photovoltaic module reliability workshop

    Mrig, L. (ed.)


    The paper and presentations compiled in this volume form the Proceedings of the fourth in a series of Workshops sponsored by Solar Energy Research Institute (SERI/DOE) under the general theme of photovoltaic module reliability during the period 1986--1990. The reliability Photo Voltaic (PV) modules/systems is exceedingly important along with the initial cost and efficiency of modules if the PV technology has to make a major impact in the power generation market, and for it to compete with the conventional electricity producing technologies. The reliability of photovoltaic modules has progressed significantly in the last few years as evidenced by warranties available on commercial modules of as long as 12 years. However, there is still need for substantial research and testing required to improve module field reliability to levels of 30 years or more. Several small groups of researchers are involved in this research, development, and monitoring activity around the world. In the US, PV manufacturers, DOE laboratories, electric utilities and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in this field were brought together under SERI/DOE sponsorship to exchange the technical knowledge and field experience as related to current information in this important field. The papers presented here reflect this effort.

  15. Reliability Centered Maintenance - Methodologies

    Kammerer, Catherine C.


    Journal article about Reliability Centered Maintenance (RCM) methodologies used by United Space Alliance, LLC (USA) in support of the Space Shuttle Program at Kennedy Space Center. The USA Reliability Centered Maintenance program differs from traditional RCM programs because various methodologies are utilized to take advantage of their respective strengths for each application. Based on operational experience, USA has customized the traditional RCM methodology into a streamlined lean logic path and has implemented the use of statistical tools to drive the process. USA RCM has integrated many of the L6S tools into both RCM methodologies. The tools utilized in the Measure, Analyze, and Improve phases of a Lean Six Sigma project lend themselves to application in the RCM process. All USA RCM methodologies meet the requirements defined in SAE JA 1011, Evaluation Criteria for Reliability-Centered Maintenance (RCM) Processes. The proposed article explores these methodologies.

  16. Gearbox Reliability Collaborative Update (Presentation)

    Sheng, S.; Keller, J.; Glinsky, C.


    This presentation was given at the Sandia Reliability Workshop in August 2013 and provides information on current statistics, a status update, next steps, and other reliability research and development activities related to the Gearbox Reliability Collaborative.

  17. System Reliability Analysis: Foundations.


    performance formulas for systems subject to pre- ventive maintenance are given. V * ~, , 9 D -2 SYSTEM RELIABILITY ANALYSIS: FOUNDATIONS Richard E...reliability in this case is V P{s can communicate with the terminal t = h(p) Sp2(((((p p)p) p)p)gp) + p(l -p)(((pL p)p)(p 2 JLp)) + p(l -p)((p(p p...For undirected networks, the basic reference is A. Satyanarayana and Kevin Wood (1982). For directed networks, the basic reference is Avinash

  18. Reserve requirements: A modern perspective

    Scott E. Hein; Jonathan D. Stewart


    The discussion in many money and banking textbooks would suggest that the Federal Reserve requires depository institutions to hold a minimum level of non-interest-earning reserves because (1) reserve requirements are a monetary policy tool that allows the Fed to expand the money supply and lower interest rates, and (2) reserve requirements improve the safety and soundness of depository institutions. This article argues that this "conventional wisdom" view is too narrow. ; The Fed often uses r...

  19. Fractional Reserve in Banking System

    Valkonen, Maria


    This thesis is aimed to provide understanding of the role of the fractional reserve in the mod-ern banking system worldwide and particularly in Finland. The fractional reserve banking is used worldwide, but the benefits of this system are very disputable. On the one hand, experts say that the fractional reserve is a necessary instrument for the normal business and profit making. On the other hand, sceptics openly criticize the fractional reserve system and blame it for fiat money (money n...

  20. Fractional Reserve in Banking System

    Valkonen, Maria


    This thesis is aimed to provide understanding of the role of the fractional reserve in the mod-ern banking system worldwide and particularly in Finland. The fractional reserve banking is used worldwide, but the benefits of this system are very disputable. On the one hand, experts say that the fractional reserve is a necessary instrument for the normal business and profit making. On the other hand, sceptics openly criticize the fractional reserve system and blame it for fiat money (money n...

  1. Component Reliability Assessment of Offshore Jacket Platforms

    V.J. Kurian


    Full Text Available Oil and gas industry is one of the most important industries contributing to the Malaysian economy. To extract hydrocarbons, various types of production platforms have been developed. Fixed jacket platform is the earliest type of production structure, widely installed in Malaysia’s shallow and intermediate waters. To date, more than 60% of these jacket platforms have operated exceeding their initial design life, thus making the re-evaluation and reassessment necessary for these platforms to continue to be put in service. In normal engineering practice, system reliability of a structure is evaluated as its safety parameter. This method is however, much complicated and time consuming. Assessing component's reliability can be an alternative approach to provide assurance about a structure’s condition in an early stage. Design codes such as the Working Stress Design (WSD and the Load and Resistance Factor Design (LRFD are well established for the component-level assessment. In reliability analysis, failure function, which consists of strength and load, is used to define the failure event. If the load acting exceeds the capacity of a structure, the structure will fail. Calculation of stress utilization ratio as given in the design codes is able to predict the reliability of a member and to estimate the extent to which a member is being utilised. The basic idea of this ratio is that if it is more than one, the member has failed and vice versa. Stress utilization ratio is a ratio of applied stress, which is the output reaction of environmental loadings acting on the structural member, to the design strength that comes from the member’s geometric and material properties. Adopting this ratio as the failure event, the reliability of each component is found. This study reviews and discusses the reliability for selected members of three Malaysian offshore jacket platforms. First Order Reliability Method (FORM was used to generate reliability index and

  2. 77 FR 40253 - Reserve Account


    .... 3. One commentator also agreed with the change to the reserve account requirements as the change... regulation to change the Reserve Account for new construction for the Sections 514/516 Farm Labor Housing... Development based its reserve account on a set percentage of a property's total development cost (TDC). With...

  3. Un aspect du calcul d'erreur sur les réserves en place d'un gisement : L'influence du nombre et de la disposition spatiale des puits One Aspect of Error Computing for Reserves in a Reservoir. Influence of Well Number and Spacing

    Haas A.


    Full Text Available L'erreur sur l'évaluation des réserves en place d'un gisement d'hydrocarbures dépend de trois facteurs : - erreur aux puits sur la détermination des porosités et saturations; - erreur géostatistique d'extension au gisement des mesures effectuées aux puits ; - erreur géométrique d'évaluation de la surface ou du volume du gisement. Dans ce texte nous avons étudié l'influence du nombre et de la distribution des puits sur l'erreur géostatistique dans le cas d'un gisement fictif de forme elliptique. Nous nous sommes placés à différents niveaux de reconnaissance, depuis l'implantation d'un seul puits en position variable jusqu'à la couverture complète du gisement par une grille régulière de 48 puits... La méthode utilisée est le « krigeage » élaboré par G. MATHERON de l'École des Mines de Paris. Les calculs ont été réalisés à l'aide du programme KRIGEPACK développé par une association CFP-SNPA. L'erreur d'estimation dépend de la position des puits dans le gisement, de la plus ou moins grande continuité spatiale de la variable et des erreurs aux puits. L'erreur que l'on peut calculer par la statistique classique ne dépend que du nombre de puits et suivant le cas peut être trop importante (si les puits sont implantés de manière optimale ou au contraire trop faible (si les puits sont mal disposés. The error in evaluating reserves in place in a hydrocarbon reservoir depends on The following three factors I - an erorr in wells when determining porosities and saturations ; 2 - a geosfatistical error in extending well measurements ta the entire reservoir; 3 - a geometric error in evaluating the area or volume of the reservoir. This article studies the influence of well number and distribution on the geostatistical error in the case of an elliptically-shaped imaginary reservoir. Various levels of exploration are considered, from the existence of a single well in various positions to full coverage of the reservoir by a

  4. Expert system aids reliability

    Johnson, A.T. [Tennessee Gas Pipeline, Houston, TX (United States)


    Quality and Reliability are key requirements in the energy transmission industry. Tennessee Gas Co. a division of El Paso Energy, has applied Gensym`s G2, object-oriented Expert System programming language as a standard tool for maintaining and improving quality and reliability in pipeline operation. Tennessee created a small team of gas controllers and engineers to develop a Proactive Controller`s Assistant (ProCA) that provides recommendations for operating the pipeline more efficiently, reliably and safely. The controller`s pipeline operating knowledge is recreated in G2 in the form of Rules and Procedures in ProCA. Two G2 programmers supporting the Gas Control Room add information to the ProCA knowledge base daily. The result is a dynamic, constantly improving system that not only supports the pipeline controllers in their operations, but also the measurement and communications departments` requests for special studies. The Proactive Controller`s Assistant development focus is in the following areas: Alarm Management; Pipeline Efficiency; Reliability; Fuel Efficiency; and Controller Development.

  5. Reliability based structural design

    Vrouwenvelder, A.C.W.M.


    According to ISO 2394, structures shall be designed, constructed and maintained in such a way that they are suited for their use during the design working life in an economic way. To fulfil this requirement one needs insight into the risk and reliability under expected and non-expected actions. A ke

  6. Reliability based structural design

    Vrouwenvelder, A.C.W.M.


    According to ISO 2394, structures shall be designed, constructed and maintained in such a way that they are suited for their use during the design working life in an economic way. To fulfil this requirement one needs insight into the risk and reliability under expected and non-expected actions. A ke

  7. The value of reliability

    Fosgerau, Mogens; Karlström, Anders


    We derive the value of reliability in the scheduling of an activity of random duration, such as travel under congested conditions. Using a simple formulation of scheduling utility, we show that the maximal expected utility is linear in the mean and standard deviation of trip duration, regardless...

  8. Parametric Mass Reliability Study

    Holt, James P.


    The International Space Station (ISS) systems are designed based upon having redundant systems with replaceable orbital replacement units (ORUs). These ORUs are designed to be swapped out fairly quickly, but some are very large, and some are made up of many components. When an ORU fails, it is replaced on orbit with a spare; the failed unit is sometimes returned to Earth to be serviced and re-launched. Such a system is not feasible for a 500+ day long-duration mission beyond low Earth orbit. The components that make up these ORUs have mixed reliabilities. Components that make up the most mass-such as computer housings, pump casings, and the silicon board of PCBs-typically are the most reliable. Meanwhile components that tend to fail the earliest-such as seals or gaskets-typically have a small mass. To better understand the problem, my project is to create a parametric model that relates both the mass of ORUs to reliability, as well as the mass of ORU subcomponents to reliability.

  9. Avionics Design for Reliability


    Consultant P.O. Box 181, Hazelwood. Missouri 63042, U.S.A. soup ""•.• • CONTENTS Page LIST OF SPEAKERS iii INTRODUCTION AND OVERVIEW-RELIABILITY UNDER... primordial , d’autant plus quo dans co cam ia procg- dure do st~lection en fiabilitg eat assez peu efficaco. La ripartition des pannes suit

  10. Wind Energy - How Reliable.


    The reliability of a wind energy system depends on the size of the propeller and the size of the back-up energy storage. Design of the optimum system...speed incidents which generate a significant part of the wind energy . A nomogram is presented, based on some continuous wind speed measurements

  11. The reliability horizon

    Visser, M


    The ``reliability horizon'' for semi-classical quantum gravity quantifies the extent to which we should trust semi-classical quantum gravity, and gives a handle on just where the ``Planck regime'' resides. The key obstruction to pushing semi-classical quantum gravity into the Planck regime is often the existence of large metric fluctuations, rather than a large back-reaction.

  12. Reliability of semiology description.

    Heo, Jae-Hyeok; Kim, Dong Wook; Lee, Seo-Young; Cho, Jinwhan; Lee, Sang-Kun; Nam, Hyunwoo


    Seizure semiology is important for classifying patients' epilepsy. Physicians usually get most of the seizure information from observers though there have been few reports on the reliability of the observers' description. This study aims at determining the reliability of observers' description of the semiology. We included 92 patients who had their habitual seizures recorded during video-EEG monitoring. We compared the semiology described by the observers with that recorded on the videotape, and reviewed which characteristics of the observers affected the reliability of their reported data. The classification of seizures and the individual components of the semiology based only on the observer-description was somewhat discordant compared with the findings from the videotape (correct classification, 85%). The descriptions of some ictal behaviors such as oroalimentary automatism, tonic/dystonic limb posturing, and head versions were relatively accurate, but those of motionless staring and hand automatism were less accurate. The specified directions by the observers were relatively correct. The accuracy of the description was related to the educational level of the observers. Much of the information described by well-educated observers is reliable. However, every physician should keep in mind the limitations of this information and use this information cautiously.

  13. High reliability organizations

    Gallis, R.; Zwetsloot, G.I.J.M.


    High Reliability Organizations (HRO’s) are organizations that constantly face serious and complex (safety) risks yet succeed in realising an excellent safety performance. In such situations acceptable levels of safety cannot be achieved by traditional safety management only. HRO’s manage safety

  14. Measuring the policy effects of changes in reserve requirement ratios

    Joseph H. Haslag; Scott E. Hein


    The monetary base is the sum of high-powered money and an adjustment factor that measures changes in reserve requirement ratios. This adjustment factor is calculated so that it responds to changes in deposit levels in addition to changes in reserve requirements. Consequently, researchers and policymakers using the monetary base are seeing a mixture of changes implemented through open market operations, discount window borrowings, and reserve requirements, together with nonpolicy actions actin...

  15. Reliability Evaluation of Slopes Using Particle Swarm Optimization

    Mohammad Khajehzadeh


    Full Text Available The objective of this research is to develop a numerical procedure to reliability evaluation of earth slope and locating the critical probabilistic slip surface. The performance function is  formulated using simplified Bishop’s limit equilibrium method  to calculate the reliability index. The reliability index defined by Hasofer and Lind is used as an index of safety measure. Searching the critical probabilistic surface that is associated with the lowest reliability index will be formulated as an optimization problem. In this paper, particle swarm optimization is applied to calculate the minimum Hasofer and Lind reliability index and critical probabilistic failure surface. To demonstrate the applicability and to investigate the effectiveness of the algorithm, two numerical examples from literature are illustrated. Results show that the proposed method is capable to achieve better solutions for reliability analysis of slope if compared with those reported in the literature.

  16. 3D photography is a reliable method of measuring infantile haemangioma volume over time.

    Robertson, Sarah A; Kimble, Roy M; Storey, Kristen J; Gee Kee, Emma L; Stockton, Kellie A


    Infantile haemangiomas are common lesions of infancy. With the development of novel treatments utilised to accelerate their regression, there is a need for a method of assessing these lesions over time. Volume is an ideal assessment method because of its quantifiable nature. This study investigated whether 3D photography is a valid tool for measuring the volume of infantile haemangiomas over time. Thirteen children with infantile haemangiomas presenting to the Vascular Anomalies Clinic, Royal Children's Hospital/Lady Cilento Children's Hospital treated with propranolol were included in the study. Lesion volume was assessed using 3D photography at presentation, one month and three months follow up. Intrarater reliability was determined by retracing all images several months after the initial mapping. Interrater reliability of the 3D camera software was determined by two investigators, blinded to each other's results, independently assessing infantile haemangioma volume. Lesion volume decreased significantly between presentation and three-month follow-up (p<0.001). Volume intra- and interrater reliability were excellent with ICC 0.991 (95% CI 0.982, 0.995) and 0.978 (95% CI 0.955, 0.989), respectively. This study demonstrates images taken with the 3D LifeViz™ camera and lesion volume calculated with Dermapix® software is a reliable method for assessing infantile haemangioma volume over time. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Study of selected problems of reliability of the supply chain in the trading company


    Full Text Available The paper presents the problems of the reliability of the supply chain as a whole in the dependence on the reliability of its elements. Different variants of reserving of canals (prime and reserve ones and issues connected with their switching are discussed.

  18. Invasive and non-invasive fractional flow reserve index in validation of hemodynamic severity of intracoronary lesions.

    Wasilewski, Jarosław; Mirota, Kryspin; Hawranek, Michał; Poloński, Lech


    This review discusses visual and functional evaluation of the hemodynamic significance of the degree of stenosis in coronary angiography, with respect to the indications for revascularization. The concept of the coronary flow reserve is defined, and the theoretical assumptions of the invasive measurement of the fractional flow reserve (FFR) are presented. In the following part, the publication describes the basic steps of numerical stimulations in terms of computational fluid dynamics (CFD) in calculating the fractional flow reserve based on computed tomography (CT) coronary angiography (FFRCT). The numerical FFRCT estimation in correlation with invasive measurements, as well as benefits deriving from FFRCT in the diagnosis of coronary artery disease, is presented in the example of the multicentre prospective DISCOVER-FLOW trial and the DeFACTO project. The CDF method enables to obtain hemodynamic significance of stenosis solely from the coronary anatomy vizualized by CT angiography. The calculation of FFRCT increases the diagnostic reliability of coronary flow reserve estimations. It contributes to the improvement in patients' qualification for contrast coronarography. If the accuracy of FFRCT is confirmed in clinical practice, and the time required for computational processing is shortened, it may turn out that the algorithms of coronary heart disease diagnosis will be verified and it will be to a greater extent based on the CT results.

  19. Reliability and Robustness Evaluation of Timber Structures

    Cizmar, Dean; Sørensen, John Dalsgaard; Kirkegaard, Poul Henning

    In the last few decades there have been intensely research concerning reliability of timber structures. This is primarily because there is an increased focus on society on sustainability and environmental aspects. Modern timber as a building material is also being competitive compared to concrete...... parameters is given. System models (series and parallel) are discused and methods for reliability calculation are given. Special attention is drawn upon brittle/ductile modelling of timber and connections. In chapter 2 robustness requirements implemended in codes are presented. State of the art definitions...

  20. Reliability in the utility computing era: Towards reliable Fog computing

    Madsen, Henrik; Burtschy, Bernard; Albeanu, G.


    This paper considers current paradigms in computing and outlines the most important aspects concerning their reliability. The Fog computing paradigm as a non-trivial extension of the Cloud is considered and the reliability of the networks of smart devices are discussed. Combining the reliability...... requirements of grid and cloud paradigms with the reliability requirements of networks of sensor and actuators it follows that designing a reliable Fog computing platform is feasible....

  1. Effect of Maintenance on Computer Network Reliability

    Rima Oudjedi Damerdji


    Full Text Available At the time of the new information technologies, computer networks are inescapable in any large organization, where they are organized so as to form powerful internal means of communication. In a context of dependability, the reliability parameter proves to be fundamental to evaluate the performances of such systems. In this paper, we study the reliability evaluation of a real computer network, through three reliability models. The computer network considered (set of PCs and server interconnected is localized in a company established in the west of Algeria and dedicated to the production of ammonia and fertilizers. The result permits to compare between the three models to determine the most appropriate reliability model to the studied network, and thus, contribute to improving the quality of the network. In order to anticipate system failures as well as improve the reliability and availability of the latter, we must put in place a policy of adequate and effective maintenance based on a new model of the most common competing risks in maintenance, Alert-Delay model. At the end, dependability measures such as MTBF and reliability are calculated to assess the effectiveness of maintenance strategies and thus, validate the alert delay model.

  2. On the reliability of seasonal climate forecasts.

    Weisheimer, A; Palmer, T N


    Seasonal climate forecasts are being used increasingly across a range of application sectors. A recent UK governmental report asked: how good are seasonal forecasts on a scale of 1-5 (where 5 is very good), and how good can we expect them to be in 30 years time? Seasonal forecasts are made from ensembles of integrations of numerical models of climate. We argue that 'goodness' should be assessed first and foremost in terms of the probabilistic reliability of these ensemble-based forecasts; reliable inputs are essential for any forecast-based decision-making. We propose that a '5' should be reserved for systems that are not only reliable overall, but where, in particular, small ensemble spread is a reliable indicator of low ensemble forecast error. We study the reliability of regional temperature and precipitation forecasts of the current operational seasonal forecast system of the European Centre for Medium-Range Weather Forecasts, universally regarded as one of the world-leading operational institutes producing seasonal climate forecasts. A wide range of 'goodness' rankings, depending on region and variable (with summer forecasts of rainfall over Northern Europe performing exceptionally poorly) is found. Finally, we discuss the prospects of reaching '5' across all regions and variables in 30 years time.

  3. Continuous Reliability Enhancement for Wind (CREW) database :

    Hines, Valerie Ann-Peters; Ogilvie, Alistair B.; Bond, Cody R.


    To benchmark the current U.S. wind turbine fleet reliability performance and identify the major contributors to component-level failures and other downtime events, the Department of Energy funded the development of the Continuous Reliability Enhancement for Wind (CREW) database by Sandia National Laboratories. This report is the third annual Wind Plant Reliability Benchmark, to publically report on CREW findings for the wind industry. The CREW database uses both high resolution Supervisory Control and Data Acquisition (SCADA) data from operating plants and Strategic Power Systems ORAPWindª (Operational Reliability Analysis Program for Wind) data, which consist of downtime and reserve event records and daily summaries of various time categories for each turbine. Together, these data are used as inputs into CREWs reliability modeling. The results presented here include: the primary CREW Benchmark statistics (operational availability, utilization, capacity factor, mean time between events, and mean downtime); time accounting from an availability perspective; time accounting in terms of the combination of wind speed and generation levels; power curve analysis; and top system and component contributors to unavailability.

  4. The Power Reserves Market Creation For The Participants Maximum Benefit

    Anatolij Mahnitko


    Full Text Available It is known, that the main task of the electric power system (EPS control is the power supply providing with the minimum expenses for the electric power production. In this case the requirement to the electric power quality, power supply reliability and the limitationson the energy resources cost must be observed. The power reserve presence into EPS is the necessary condition of the guaranteeing the normal operation from the point of view of the regime parameters values. In the proposed paper the problem of the developing the power reserve, presented to sale by the electric power producers, is examined. It is considered the procedure of the power reserve pricedetermination.

  5. Structural hybrid reliability index and its convergent solving method based on random–fuzzy–interval reliability model

    Hai An


    Full Text Available Aiming to resolve the problems of a variety of uncertainty variables that coexist in the engineering structure reliability analysis, a new hybrid reliability index to evaluate structural hybrid reliability, based on the random–fuzzy–interval model, is proposed in this article. The convergent solving method is also presented. First, the truncated probability reliability model, the fuzzy random reliability model, and the non-probabilistic interval reliability model are introduced. Then, the new hybrid reliability index definition is presented based on the random–fuzzy–interval model. Furthermore, the calculation flowchart of the hybrid reliability index is presented and it is solved using the modified limit-step length iterative algorithm, which ensures convergence. And the validity of convergent algorithm for the hybrid reliability model is verified through the calculation examples in literature. In the end, a numerical example is demonstrated to show that the hybrid reliability index is applicable for the wear reliability assessment of mechanisms, where truncated random variables, fuzzy random variables, and interval variables coexist. The demonstration also shows the good convergence of the iterative algorithm proposed in this article.

  6. A Study on the Reliability of a Large Vibration Machine


    This study aims at the reliability of a large vibration machine ZM2800, including the measurement and analysis of its dynamic load, the stress and reliability analysis of key fragile components as well as the system reliability analysis and calculation of the ma chine. The result of the study provides valuable reference for the evaluation and improve-ment of the structure and performance of the machine.

  7. The 747 primary flight control systems reliability and maintenance study


    The major operational characteristics of the 747 Primary Flight Control Systems (PFCS) are described. Results of reliability analysis for separate control functions are presented. The analysis makes use of a NASA computer program which calculates reliability of redundant systems. Costs for maintaining the 747 PFCS in airline service are assessed. The reliabilities and cost will provide a baseline for use in trade studies of future flight control system design.

  8. Reliability Analysis of Slope Stability by Central Point Method

    Li, Chunge; WU Congliang


    Given uncertainty and variability of the slope stability analysis parameter, the paper proceed from the perspective of probability theory and statistics based on the reliability theory. Through the central point method of reliability analysis, performance function about the reliability of slope stability analysis is established. What’s more, the central point method and conventional limit equilibrium methods do comparative analysis by calculation example. The approach’s numerical ...

  9. Fuzzy Reliability Analysis of the Shaft of a Steam Turbine


    Field surveying shows that the failure of the steam turbine's coupling is due to fatigue that is caused by compound stress. Fuzzy mathematics was applied to get the membership function of the fatigue strength rule. A formula of fuzzy reliability of the coupling was derived and a theory of coupling's fuzzy reliability is set up. The calculating method of the fuzzy reliability is explained by an illustrative example.

  10. Equivalent reliability polynomials modeling EAS and their geometries

    Hassan Zahir Abdul Haddi


    Full Text Available In this paper we shall introduce two equivalent techniques in order to evaluate reliability analysis of electrical aircrafts systems (EAS: (i graph theory technique, and (ii simplifying diffeomorphism technique. Geometric modeling of reliability models is based on algebraic hypersurfaces, whose intrinsic properties are able to select those models which are relevant for applications. The basic idea is to cover the reliability hypersurfaces by exponentially decay curves. Most of the calculations made in this paper have used Maple and Matlab software.

  11. Construction of a reliable model pyranometer for irradiance ...



    Mar 22, 2010 ... design, construction and testing of a reliable model pyranometer (RMP001) was done in Mubi,. Adamawa ... Pyranometers are widely used in meteorology, climate- .... It is calculated that an appropriate value for the capa-.

  12. Status of lattice field theory calculations

    Sharpe, S.R.


    This report briefly discusses the following topics: overview of all present calculation; reliability criteria for quenched calculation; quenched versus full QCD, and difficulties facing full QCD; results for the quenched pion wavefunction''; results for the quenched hadron spectrum; results for quenched B{sub K}; A new method for calculating the surface tension; the non-pertubative upper bound on the Higgs mass; and toward the TERAFLOP machine.

  13. Human Reliability Program Workshop

    Landers, John; Rogers, Erin; Gerke, Gretchen


    A Human Reliability Program (HRP) is designed to protect national security as well as worker and public safety by continuously evaluating the reliability of those who have access to sensitive materials, facilities, and programs. Some elements of a site HRP include systematic (1) supervisory reviews, (2) medical and psychological assessments, (3) management evaluations, (4) personnel security reviews, and (4) training of HRP staff and critical positions. Over the years of implementing an HRP, the Department of Energy (DOE) has faced various challenges and overcome obstacles. During this 4-day activity, participants will examine programs that mitigate threats to nuclear security and the insider threat to include HRP, Nuclear Security Culture (NSC) Enhancement, and Employee Assistance Programs. The focus will be to develop an understanding of the need for a systematic HRP and to discuss challenges and best practices associated with mitigating the insider threat.

  14. Accelerator reliability workshop

    Hardy, L.; Duru, Ph.; Koch, J.M.; Revol, J.L.; Van Vaerenbergh, P.; Volpe, A.M.; Clugnet, K.; Dely, A.; Goodhew, D


    About 80 experts attended this workshop, which brought together all accelerator communities: accelerator driven systems, X-ray sources, medical and industrial accelerators, spallation sources projects (American and European), nuclear physics, etc. With newly proposed accelerator applications such as nuclear waste transmutation, replacement of nuclear power plants and others. Reliability has now become a number one priority for accelerator designers. Every part of an accelerator facility from cryogenic systems to data storage via RF systems are concerned by reliability. This aspect is now taken into account in the design/budget phase, especially for projects whose goal is to reach no more than 10 interruptions per year. This document gathers the slides but not the proceedings of the workshop.

  15. Improving Power Converter Reliability

    Ghimire, Pramod; de Vega, Angel Ruiz; Beczkowski, Szymon


    The real-time junction temperature monitoring of a high-power insulated-gate bipolar transistor (IGBT) module is important to increase the overall reliability of power converters for industrial applications. This article proposes a new method to measure the on-state collector?emitter voltage...... of a high-power IGBT module during converter operation, which may play a vital role in improving the reliability of the power converters. The measured voltage is used to estimate the module average junction temperature of the high and low-voltage side of a half-bridge IGBT separately in every fundamental...... is measured in a wind power converter at a low fundamental frequency. To illustrate more, the test method as well as the performance of the measurement circuit are also presented. This measurement is also useful to indicate failure mechanisms such as bond wire lift-off and solder layer degradation...

  16. Power electronics reliability.

    Kaplar, Robert James; Brock, Reinhard C.; Marinella, Matthew; King, Michael Patrick; Stanley, James K.; Smith, Mark A.; Atcitty, Stanley


    The project's goals are: (1) use experiments and modeling to investigate and characterize stress-related failure modes of post-silicon power electronic (PE) devices such as silicon carbide (SiC) and gallium nitride (GaN) switches; and (2) seek opportunities for condition monitoring (CM) and prognostics and health management (PHM) to further enhance the reliability of power electronics devices and equipment. CM - detect anomalies and diagnose problems that require maintenance. PHM - track damage growth, predict time to failure, and manage subsequent maintenance and operations in such a way to optimize overall system utility against cost. The benefits of CM/PHM are: (1) operate power conversion systems in ways that will preclude predicted failures; (2) reduce unscheduled downtime and thereby reduce costs; and (3) pioneering reliability in SiC and GaN.

  17. Biosphere reserves: Attributes for success.

    Van Cuong, Chu; Dart, Peter; Hockings, Marc


    Biosphere reserves established under the UNESCO Man and the Biosphere Program aim to harmonise biodiversity conservation and sustainable development. Concerns over the extent to which the reserve network was living up to this ideal led to the development of a new strategy in 1995 (the Seville Strategy) to enhance the operation of the network of reserves. An evaluation of effectiveness of management of the biosphere reserve network was called for as part of this strategy. Expert opinion was assembled through a Delphi Process to identify successful and less successful reserves and investigate common factors influencing success or failure. Ninety biosphere reserves including sixty successful and thirty less successful reserves in 42 countries across all five Man and the Biosphere Program regions were identified. Most successful sites are the post-Seville generation while the majority of unsuccessful sites are pre-Seville that are managed as national parks and have not been amended to conform to the characteristics that are meant to define a biosphere reserve. Stakeholder participation and collaboration, governance, finance and resources, management, and awareness and communication are the most influential factors in the success or failure of the biosphere reserves. For success, the biosphere reserve concept needs to be clearly understood and applied through landscape zoning. Designated reserves then need a management system with inclusive good governance, strong participation and collaboration, adequate finance and human resource allocation and stable and responsible management and implementation. All rather obvious but it is difficult to achieve without commitment to the biosphere reserve concept by the governance authorities. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. ATLAS reliability analysis

    Bartsch, R.R.


    Key elements of the 36 MJ ATLAS capacitor bank have been evaluated for individual probabilities of failure. These have been combined to estimate system reliability which is to be greater than 95% on each experimental shot. This analysis utilizes Weibull or Weibull-like distributions with increasing probability of failure with the number of shots. For transmission line insulation, a minimum thickness is obtained and for the railgaps, a method for obtaining a maintenance interval from forthcoming life tests is suggested.

  19. Reliability of Circumplex Axes

    Micha Strack


    Full Text Available We present a confirmatory factor analysis (CFA procedure for computing the reliability of circumplex axes. The tau-equivalent CFA variance decomposition model estimates five variance components: general factor, axes, scale-specificity, block-specificity, and item-specificity. Only the axes variance component is used for reliability estimation. We apply the model to six circumplex types and 13 instruments assessing interpersonal and motivational constructs—Interpersonal Adjective List (IAL, Interpersonal Adjective Scales (revised; IAS-R, Inventory of Interpersonal Problems (IIP, Impact Messages Inventory (IMI, Circumplex Scales of Interpersonal Values (CSIV, Support Action Scale Circumplex (SAS-C, Interaction Problems With Animals (IPI-A, Team Role Circle (TRC, Competing Values Leadership Instrument (CV-LI, Love Styles, Organizational Culture Assessment Instrument (OCAI, Customer Orientation Circle (COC, and System for Multi-Level Observation of Groups (behavioral adjectives; SYMLOG—in 17 German-speaking samples (29 subsamples, grouped by self-report, other report, and metaperception assessments. The general factor accounted for a proportion ranging from 1% to 48% of the item variance, the axes component for 2% to 30%; and scale specificity for 1% to 28%, respectively. Reliability estimates varied considerably from .13 to .92. An application of the Nunnally and Bernstein formula proposed by Markey, Markey, and Tinsley overestimated axes reliabilities in cases of large-scale specificities but otherwise works effectively. Contemporary circumplex evaluations such as Tracey’s RANDALL are sensitive to the ratio of the axes and scale-specificity components. In contrast, the proposed model isolates both components.


    Gaguk Margono


    Full Text Available The purpose of this paper is to compare unidimensional reliability and multidimensional reliability of instrument students’ satisfaction as an internal costumer. Multidimensional reliability measurement is rarely used in the field of research. Multidimensional reliability is estimated by using Confirmatory Factor Analysis (CFA on the Structural Equation Model (SEM. Measurements and calculations are described in this article using instrument students’ satisfaction as an internal costumer. Survey method used in this study and sampling used simple random sampling. This instrument has been tried out to 173 students. The result is concluded that the measuringinstrument of students’ satisfaction as an internal costumer by using multidimensional reliability coefficient has higher accuracy when compared with a unidimensional reliability coefficient. Expected in advanced research used another formula multidimensional reliability, including when using SEM.

  1. Mechanical reliability analysis of tubes intended for hydrocarbons

    Nahal, Mourad; Khelif, Rabia [Badji Mokhtar University, Annaba (Algeria)


    Reliability analysis constitutes an essential phase in any study concerning reliability. Many industrialists evaluate and improve the reliability of their products during the development cycle - from design to startup (design, manufacture, and exploitation) - to develop their knowledge on cost/reliability ratio and to control sources of failure. In this study, we obtain results for hardness, tensile, and hydrostatic tests carried out on steel tubes for transporting hydrocarbons followed by statistical analysis. Results obtained allow us to conduct a reliability study based on resistance request. Thus, index of reliability is calculated and the importance of the variables related to the tube is presented. Reliability-based assessment of residual stress effects is applied to underground pipelines under a roadway, with and without active corrosion. Residual stress has been found to greatly increase probability of failure, especially in the early stages of pipe lifetime.

  2. Results from the LHC Beam Dump Reliability Run

    Uythoven, J; Carlier, E; Castronuovo, F; Ducimetière, L; Gallet, E; Goddard, B; Magnin, N; Verhagen, H


    The LHC Beam Dumping System is one of the vital elements of the LHC Machine Protection System and has to operate reliably every time a beam dump request is made. Detailed dependability calculations have been made, resulting in expected rates for the different system failure modes. A 'reliability run' of the whole system, installed in its final configuration in the LHC, has been made to discover infant mortality problems and to compare the occurrence of the measured failure modes with their calculations.

  3. Improvement of the reliability on nondestructive inspection

    Song, Sung Jin; Kim, Young H. [Sungkyunkwan Univ., Suwon (Korea, Republic of); Lee, Hyang Beom [Soongsil Univ., Seoul (Korea, Republic of); Shin, Young Kil [Kunsan National Univ., Gunsan (Korea, Republic of); Jung, Hyun Jo [Wonkwang Univ., Iksan (Korea, Republic of); Park, Ik Keun; Park, Eun Soo [Seoul Nationl Univ., Seoul (Korea, Republic of)


    Retaining reliabilities of nondestructive testing is essential for the life-time maintenance of Nuclear Power Plant. The nondestructive testing methods which are frequently used in the Nuclear Power Plant are eddy current testing for the inspection of steam generator tubes and ultrasonic testing for the inspection of weldments. In order to improve reliabilities of ultrasonic testing and eddy current testing, the subjects carried out in this study are as follows : development of BEM analysis technique for ECT of SG tube, development of neural network technique for the intelligent analysis of ECT flaw signals of SG tubes, development of RFECT technology for the inspection of SG tube, FEM analysis of ultrasonic scattering field, evaluation of statistical reliability of PD-RR test of ultrasonic testing and development of multi-Gaussian beam modeling technique to predict accurate signal of signal beam ultrasonic testing with the efficiency in calculation time.

  4. Nuclear, uranium, reserves, sustainability, independence; Nucleaire, Uranium, reserves, durabilite, independance

    Acket, C


    In order to evaluate the energy independence concerning the nuclear energy, the author takes the state of the art about the uranium. He details the fuel needs, the reserves on the base of the today available techniques, the reserves on the base of the future techniques and concludes positively on the energy independence for the nuclear. (A.L.B.)

  5. 77 FR 21846 - Reserve Requirements of Depository Institutions: Reserves Simplification


    ... liabilities of depository institutions for the purpose of implementing monetary policy. The Board's Regulation... monetary policy. If the Federal Reserve changes its monetary policy framework, which includes the payment... affect the Federal Reserve's ability to implement monetary policy in the event that all depository...

  6. Pinpointing extractable oil reserves according to dynamics of samplings

    Berezhnoy, N.I.; Dalinchuk, O.V.; Frolova, N.N.


    An analytical method is presented for calculating the extractable oil reserves with deviation of the actual incident branch of the sampling model from the statistical. An example is presented of the calculation for the lower operating object of the Zapadno-Tebukskiy field which corresponds to the III type of model (according to G.I. Permyakov).

  7. Reliability of Transcallosal Inhibition in Healthy Adults

    Fleming, Melanie K.; Newham, Di J.


    Transcallosal inhibition (TCI), assessed using transcranial magnetic stimulation, can provide insight into the neurophysiology of aging and of neurological disorders such as stroke. However, the reliability of TCI using the ipsilateral silent period (iSP) has not been formally assessed, despite its use in longitudinal studies. This study aimed to determine the reliability of iSP onset latency, duration and depth in healthy young and older adults. A sample of 18 younger (mean age 27.7 years, range: 19–42) and 13 older healthy adults (mean age 68.1 years, range: 58–79) attended four sessions whereby the iSP was measured from the first dorsal interosseous (FDI) muscle of each hand. 20 single pulse stimuli were delivered to each primary motor cortex at 80% maximum stimulator output while the participant maintained an isometric contraction of the ipsilateral FDI. The average onset latency, duration of the iSP, and depth of inhibition relative to baseline electromyography activity was calculated for each hand in each session. Intraclass correlation coefficients (ICCs) were calculated for all four sessions, or the first two sessions only. For iSP onset latency the reliability ranged from poor to good. For iSP duration there was moderate to good reliability (ICC > 0.6). Depth of inhibition demonstrated variation in reproducibility depending on which hand was assessed and whether two or four sessions were compared. Bland and Altman analyses showed wide limits of agreement between the first two sessions, particularly for iSP depth. However, there was no systematic pattern to the variability. These results indicate that although iSP duration is reliable in healthy adults, changes in longitudinal studies should be interpreted with caution, particularly for iSP depth. Future studies are needed to determine reliability in clinical populations. PMID:28119588


    Bowerman, P. N.


    RELAV (Reliability/Availability Analysis Program) is a comprehensive analytical tool to determine the reliability or availability of any general system which can be modeled as embedded k-out-of-n groups of items (components) and/or subgroups. Both ground and flight systems at NASA's Jet Propulsion Laboratory have utilized this program. RELAV can assess current system performance during the later testing phases of a system design, as well as model candidate designs/architectures or validate and form predictions during the early phases of a design. Systems are commonly modeled as System Block Diagrams (SBDs). RELAV calculates the success probability of each group of items and/or subgroups within the system assuming k-out-of-n operating rules apply for each group. The program operates on a folding basis; i.e. it works its way towards the system level from the most embedded level by folding related groups into single components. The entire folding process involves probabilities; therefore, availability problems are performed in terms of the probability of success, and reliability problems are performed for specific mission lengths. An enhanced cumulative binomial algorithm is used for groups where all probabilities are equal, while a fast algorithm based upon "Computing k-out-of-n System Reliability", Barlow & Heidtmann, IEEE TRANSACTIONS ON RELIABILITY, October 1984, is used for groups with unequal probabilities. Inputs to the program include a description of the system and any one of the following: 1) availabilities of the items, 2) mean time between failures and mean time to repairs for the items from which availabilities are calculated, 3) mean time between failures and mission length(s) from which reliabilities are calculated, or 4) failure rates and mission length(s) from which reliabilities are calculated. The results are probabilities of success of each group and the system in the given configuration. RELAV assumes exponential failure distributions for

  9. Marine reserves with ecological uncertainty.

    Grafton, R Quentin; Kompas, Tom; Lindenmayer, David


    To help manage the fluctuations inherent in fish populations scientists have argued for both an ecosystem approach to management and the greater use of marine reserves. Support for reserves includes empirical evidence that they can raise the spawning biomass and mean size of exploited populations, increase the abundance of species and, relative to reference sites, raise population density, biomass, fish size and diversity. By contrast, fishers often oppose the establishment and expansion of marine reserves and claim that reserves provide few, if any, economic payoffs. Using a stochastic optimal control model with two forms of ecological uncertainty we demonstrate that reserves create a resilience effect that allows for the population to recover faster, and can also raise the harvest immediately following a negative shock. The tradeoff of a larger reserve is a reduced harvest in the absence of a negative shock such that a reserve will never encompass the entire population if the goal is to maximize the economic returns from harvesting, and fishing is profitable. Under a wide range of parameter values with ecological uncertainty, and in the 'worst case' scenario for a reserve, we show that a marine reserve can increase the economic payoff to fishers even when the harvested population is not initially overexploited, harvesting is economically optimal and the population is persistent. Moreover, we show that the benefits of a reserve cannot be achieved by existing effort or output controls. Our results demonstrate that, in many cases, there is no tradeoff between the economic payoff of fishers and ecological benefits when a reserve is established at equal to, or less than, its optimum size.

  10. CR reliability testing

    Honeyman-Buck, Janice C.; Rill, Lynn; Frost, Meryll M.; Staab, Edward V.


    The purpose of this work was to develop a method for systematically testing the reliability of a CR system under realistic daily loads in a non-clinical environment prior to its clinical adoption. Once digital imaging replaces film, it will be very difficult to revert back should the digital system become unreliable. Prior to the beginning of the test, a formal evaluation was performed to set the benchmarks for performance and functionality. A formal protocol was established that included all the 62 imaging plates in the inventory for each 24-hour period in the study. Imaging plates were exposed using different combinations of collimation, orientation, and SID. Anthropomorphic phantoms were used to acquire images of different sizes. Each combination was chosen randomly to simulate the differences that could occur in clinical practice. The tests were performed over a wide range of times with batches of plates processed to simulate the temporal constraints required by the nature of portable radiographs taken in the Intensive Care Unit (ICU). Current patient demographics were used for the test studies so automatic routing algorithms could be tested. During the test, only three minor reliability problems occurred, two of which were not directly related to the CR unit. One plate was discovered to cause a segmentation error that essentially reduced the image to only black and white with no gray levels. This plate was removed from the inventory to be replaced. Another problem was a PACS routing problem that occurred when the DICOM server with which the CR was communicating had a problem with disk space. The final problem was a network printing failure to the laser cameras. Although the units passed the reliability test, problems with interfacing to workstations were discovered. The two issues that were identified were the interpretation of what constitutes a study for CR and the construction of the look-up table for a proper gray scale display.

  11. Ultimately Reliable Pyrotechnic Systems

    Scott, John H.; Hinkel, Todd


    This paper presents the methods by which NASA has designed, built, tested, and certified pyrotechnic devices for high reliability operation in extreme environments and illustrates the potential applications in the oil and gas industry. NASA's extremely successful application of pyrotechnics is built upon documented procedures and test methods that have been maintained and developed since the Apollo Program. Standards are managed and rigorously enforced for performance margins, redundancy, lot sampling, and personnel safety. The pyrotechnics utilized in spacecraft include such devices as small initiators and detonators with the power of a shotgun shell, detonating cord systems for explosive energy transfer across many feet, precision linear shaped charges for breaking structural membranes, and booster charges to actuate valves and pistons. NASA's pyrotechnics program is one of the more successful in the history of Human Spaceflight. No pyrotechnic device developed in accordance with NASA's Human Spaceflight standards has ever failed in flight use. NASA's pyrotechnic initiators work reliably in temperatures as low as -420 F. Each of the 135 Space Shuttle flights fired 102 of these initiators, some setting off multiple pyrotechnic devices, with never a failure. The recent landing on Mars of the Opportunity rover fired 174 of NASA's pyrotechnic initiators to complete the famous '7 minutes of terror.' Even after traveling through extreme radiation and thermal environments on the way to Mars, every one of them worked. These initiators have fired on the surface of Titan. NASA's design controls, procedures, and processes produce the most reliable pyrotechnics in the world. Application of pyrotechnics designed and procured in this manner could enable the energy industry's emergency equipment, such as shutoff valves and deep-sea blowout preventers, to be left in place for years in extreme environments and still be relied upon to function when needed, thus greatly enhancing

  12. Ferrite logic reliability study

    Baer, J. A.; Clark, C. B.


    Development and use of digital circuits called all-magnetic logic are reported. In these circuits the magnetic elements and their windings comprise the active circuit devices in the logic portion of a system. The ferrite logic device belongs to the all-magnetic class of logic circuits. The FLO device is novel in that it makes use of a dual or bimaterial ferrite composition in one physical ceramic body. This bimaterial feature, coupled with its potential for relatively high speed operation, makes it attractive for high reliability applications. (Maximum speed of operation approximately 50 kHz.)

  13. Blade reliability collaborative :

    Ashwill, Thomas D.; Ogilvie, Alistair B.; Paquette, Joshua A.


    The Blade Reliability Collaborative (BRC) was started by the Wind Energy Technologies Department of Sandia National Laboratories and DOE in 2010 with the goal of gaining insight into planned and unplanned O&M issues associated with wind turbine blades. A significant part of BRC is the Blade Defect, Damage and Repair Survey task, which will gather data from blade manufacturers, service companies, operators and prior studies to determine details about the largest sources of blade unreliability. This report summarizes the initial findings from this work.

  14. Disjoint sum forms in reliability theory

    B. Anrig


    Full Text Available The structure function f of a binary monotone system is assumed to be known and given in a disjunctive normal form, i.e. as the logical union of products of the indicator variables of the states of its subsystems. Based on this representation of f, an improved Abraham algorithm is proposed for generating the disjoint sum form of f. This form is the base for subsequent numerical reliability calculations. The approach is generalized to multivalued systems. Examples are discussed.

  15. Major Nature Reserves in China


    At the end of 2010,China had 2,588 nature reserves,covering 14.9 percent of its land area.These nature reserves have effectively protected more than 90 percent of land ecosystems,85 percent of wild animals and 65 percent of higher plant species

  16. Operating Reserves and Variable Generation

    Ela, E.; Milligan, M.; Kirby, B.


    This report tries to first generalize the requirements of the power system as it relates to the needs of operating reserves. It also includes a survey of operating reserves and how they are managed internationally in system operations today and then how new studies and research are proposing they may be managed in the future with higher penetrations of variable generation.

  17. Can Creativity Predict Cognitive Reserve?

    Palmiero, Massimiliano; Di Giacomo, Dina; Passafiume, Domenico


    Cognitive reserve relies on the ability to effectively cope with aging and brain damage by using alternate processes to approach tasks when standard approaches are no longer available. In this study, the issue if creativity can predict cognitive reserve has been explored. Forty participants (mean age: 61 years) filled out: the Cognitive Reserve…

  18. Can Creativity Predict Cognitive Reserve?

    Palmiero, Massimiliano; Di Giacomo, Dina; Passafiume, Domenico


    Cognitive reserve relies on the ability to effectively cope with aging and brain damage by using alternate processes to approach tasks when standard approaches are no longer available. In this study, the issue if creativity can predict cognitive reserve has been explored. Forty participants (mean age: 61 years) filled out: the Cognitive Reserve…

  19. Conditional Reliability Coefficients for Test Scores.

    Nicewander, W Alan


    The most widely used, general index of measurement precision for psychological and educational test scores is the reliability coefficient-a ratio of true variance for a test score to the true-plus-error variance of the score. In item response theory (IRT) models for test scores, the information function is the central, conditional index of measurement precision. In this inquiry, conditional reliability coefficients for a variety of score types are derived as simple transformations of information functions. It is shown, for example, that the conditional reliability coefficient for an ordinary, number-correct score, X, is equal to, ρ(X,X'|θ)=I(X,θ)/[I(X,θ)+1] Where: θ is a latent variable measured by an observed test score, X; p(X, X'|θ) is the conditional reliability of X at a fixed value of θ; and I(X, θ) is the score information function. This is a surprisingly simple relationship between the 2, basic indices of measurement precision from IRT and classical test theory (CTT). This relationship holds for item scores as well as test scores based on sums of item scores-and it holds for dichotomous as well as polytomous items, or a mix of both item types. Also, conditional reliabilities are derived for computerized adaptive test scores, and for θ-estimates used as alternatives to number correct scores. These conditional reliabilities are all related to information in a manner similar-or-identical to the 1 given above for the number-correct (NC) score. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Reliability and validity of the Dutch pediatric Voice Handicap Index.

    Veder, Laura; Pullens, Bas; Timmerman, Marieke; Hoeve, Hans; Joosten, Koen; Hakkesteegt, Marieke


    The pediatric voice handicap index (pVHI) has been developed to provide a better insight into the parents' perception of their child's voice related quality of life. The purpose of the present study was to validate the Dutch pVHI by evaluating its internal consistency and reliability. Furthermore, we determined the optimal cut-off point for a normal pVHI score. All items of the English pVHI were translated into Dutch. Parents of children in our dysphonic and control group were asked to fill out the questionnaire. For the test re-test analysis we used a different study group who filled out the pVHI twice as part of a large follow up study. Internal consistency was analyzed through Cronbach's α coefficient. The test-retest reliability was assessed by determining Pearson's correlation coefficient. Mann-Whitney test was used to compare the scores of the questionnaire of the control group with the dysphonic group. By calculating receiver operating characteristic (ROC) curves, sensitivity and specificity we were able to set a cut-off point. We obtained data from 122 asymptomatic children and from 79 dysphonic children. The scores of the questionnaire significantly differed between both groups. The internal consistency showed an overall Cronbach α coefficient of 0.96 and an excellent test-retest reliability of the total pVHI questionnaire with a Pearson's correlation coefficient of 0.90. A cut-off point for the total pVHI questionnaire was set at 7 points with a specificity of 85% and sensitivity of 100%. A cut-off point for the VAS score was set at 13 with a specificity of 93% and sensitivity of 97%. The Dutch pVHI is a valid and reliable tool for the assessment of children with voice problems. By setting a cut-off point for the score of the total pVHI questionnaire of 7 points and the VAS score of 13, the pVHI might be used as a screening tool to assess dysphonic complaints and the pVHI might be a useful and complementary tool to identify children with dysphonia

  1. Load Control System Reliability

    Trudnowski, Daniel [Montana Tech of the Univ. of Montana, Butte, MT (United States)


    This report summarizes the results of the Load Control System Reliability project (DOE Award DE-FC26-06NT42750). The original grant was awarded to Montana Tech April 2006. Follow-on DOE awards and expansions to the project scope occurred August 2007, January 2009, April 2011, and April 2013. In addition to the DOE monies, the project also consisted of matching funds from the states of Montana and Wyoming. Project participants included Montana Tech; the University of Wyoming; Montana State University; NorthWestern Energy, Inc., and MSE. Research focused on two areas: real-time power-system load control methodologies; and, power-system measurement-based stability-assessment operation and control tools. The majority of effort was focused on area 2. Results from the research includes: development of fundamental power-system dynamic concepts, control schemes, and signal-processing algorithms; many papers (including two prize papers) in leading journals and conferences and leadership of IEEE activities; one patent; participation in major actual-system testing in the western North American power system; prototype power-system operation and control software installed and tested at three major North American control centers; and, the incubation of a new commercial-grade operation and control software tool. Work under this grant certainly supported the DOE-OE goals in the area of “Real Time Grid Reliability Management.”

  2. Supply chain reliability modelling

    Eugen Zaitsev


    Full Text Available Background: Today it is virtually impossible to operate alone on the international level in the logistics business. This promotes the establishment and development of new integrated business entities - logistic operators. However, such cooperation within a supply chain creates also many problems related to the supply chain reliability as well as the optimization of the supplies planning. The aim of this paper was to develop and formulate the mathematical model and algorithms to find the optimum plan of supplies by using economic criterion and the model for the probability evaluating of non-failure operation of supply chain. Methods: The mathematical model and algorithms to find the optimum plan of supplies were developed and formulated by using economic criterion and the model for the probability evaluating of non-failure operation of supply chain. Results and conclusions: The problem of ensuring failure-free performance of goods supply channel analyzed in the paper is characteristic of distributed network systems that make active use of business process outsourcing technologies. The complex planning problem occurring in such systems that requires taking into account the consumer's requirements for failure-free performance in terms of supply volumes and correctness can be reduced to a relatively simple linear programming problem through logical analysis of the structures. The sequence of the operations, which should be taken into account during the process of the supply planning with the supplier's functional reliability, was presented.

  3. Earth slope reliability analysis under seismic loadings using neural network

    PENG Huai-sheng; DENG Jian; GU De-sheng


    A new method was proposed to cope with the earth slope reliability problem under seismic loadings. The algorithm integrates the concepts of artificial neural network, the first order second moment reliability method and the deterministic stability analysis method of earth slope. The performance function and its derivatives in slope stability analysis under seismic loadings were approximated by a trained multi-layer feed-forward neural network with differentiable transfer functions. The statistical moments calculated from the performance function values and the corresponding gradients using neural network were then used in the first order second moment method for the calculation of the reliability index in slope safety analysis. Two earth slope examples were presented for illustrating the applicability of the proposed approach. The new method is effective in slope reliability analysis. And it has potential application to other reliability problems of complicated engineering structure with a considerably large number of random variables.

  4. Validity and reliability of eating disorder assessments used with athletes: A review

    Zachary Pope


    Conclusion: Only seven studies calculated validity coefficients within the study whereas 47 cited the validity coefficient. Twenty-six calculated a reliability coefficient whereas 47 cited the reliability of the ED measures. Four studies found validity evidence for the EAT, EDI, BULIT-R, QEDD, and EDE-Q in an athlete population. Few studies reviewed calculated validity and reliability coefficients of ED measures. Cross-validation of these measures in athlete populations is clearly needed.

  5. OSS reliability measurement and assessment

    Yamada, Shigeru


    This book analyses quantitative open source software (OSS) reliability assessment and its applications, focusing on three major topic areas: the Fundamentals of OSS Quality/Reliability Measurement and Assessment; the Practical Applications of OSS Reliability Modelling; and Recent Developments in OSS Reliability Modelling. Offering an ideal reference guide for graduate students and researchers in reliability for open source software (OSS) and modelling, the book introduces several methods of reliability assessment for OSS including component-oriented reliability analysis based on analytic hierarchy process (AHP), analytic network process (ANP), and non-homogeneous Poisson process (NHPP) models, the stochastic differential equation models and hazard rate models. These measurement and management technologies are essential to producing and maintaining quality/reliable systems using OSS.

  6. Reliability and validity in research.

    Roberts, Paula; Priest, Helena

    This article examines reliability and validity as ways to demonstrate the rigour and trustworthiness of quantitative and qualitative research. The authors discuss the basic principles of reliability and validity for readers who are new to research.

  7. Reliability of fractional flow reserve on diagnosis of intermediate coronary stenosis in patients with diabetes%心肌血流储备分数评价糖尿病患者冠状动脉临界病变的可靠性

    梁建文; 张东辉; 吴剑胜


    目的 通过测定冠状动脉中等程度狭窄的糖尿病和非糖尿病患者的心肌血流储备分数(fractional flow reserve,FFR)来评估糖尿病对FFR检测的影响.方法 本研究入组68例冠状动脉造影明确诊断为冠状动脉粥样硬化性心脏病(冠心病),且经量化冠状动脉造影(quantitative coronary angiography,QCA)诊断为中等程度狭窄的患者,分为糖尿病组和非糖尿病组;再根据病变处管腔狭窄程度进一步细分为50%~60%亚组和60%~70%亚组;根据糖化血红蛋白(glycated hemoglobin,GHb)水平分为GHb≥7.0亚组和GHb<7.0亚组.以三磷腺苷(ATP)为冠状动脉扩张剂.比较每两组间FFR的测量值(两次取平均值)及冠状动脉扩张前后的FFR差值.结果 冠状动脉狭窄程度相似的糖尿病组和非糖尿病组的FFR比较,差异无统计学意义[50%~60%亚组:(0.84±0.06)vs.(0.86±0.08),P=0.45;60%~70%亚组:[(0.76±0.09) vs.(0.81±0.07),P=0.061].糖尿病GHb≥7.0亚组的FFR高于糖尿病GHb<7.0亚组,差异有统计学意义[(0.77±0.06)ws.(0.72±0.11),P<0.05].结论 糖尿病对测定中等程度狭窄的冠状动脉的FFR没有明显影响,糖尿病且GHb≥7.0患者的FFR较GHb<7.0患者高.

  8. Coronary flow velocity reserve by echocardiography

    Olsen, Rasmus Huan; Pedersen, Lene Rørholm; Snoer, Martin


    reserve (MFR) measured by PET in overweight and obese patients. METHODS: Participants with revascularized coronary artery disease were examined by CFVR. Subgroups were examined by repeated CFVR (reproducibility) or Rubidium-82-PET (agreement). To account for time variation, results were computed for scans...... %, and reliability 0.97. Agreement with MFR of the LAD territory (n = 35) was without significant bias and overall LOA were (-1.40;1.46). Agreement was best for examinations performed within 1-week of participants without MI of the LAD-territory (n = 12); LOA = (-0.68;0.88). CONCLUSIONS: CFVR was highly feasible...... with a good reproducibility on par with other contemporary measures applied in cardiology. Agreement with MFR was acceptable, though discrepancy related to prior MI has to be considered. CFVR of LAD is a valid tool in overweight and obese patients....

  9. 2017 NREL Photovoltaic Reliability Workshop

    Kurtz, Sarah [National Renewable Energy Laboratory (NREL), Golden, CO (United States)


    NREL's Photovoltaic (PV) Reliability Workshop (PVRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology -- both critical goals for moving PV technologies deeper into the electricity marketplace.

  10. Testing for PV Reliability (Presentation)

    Kurtz, S.; Bansal, S.


    The DOE SUNSHOT workshop is seeking input from the community about PV reliability and how the DOE might address gaps in understanding. This presentation describes the types of testing that are needed for PV reliability and introduces a discussion to identify gaps in our understanding of PV reliability testing.

  11. Managing and operating the reserve market as one insurance system

    Liu, Youfei; Cai, Bin [Electric Dispatch Center, JiangXi Electric Power Company (JXEPC), NanChang, JiangXi (China); Wu, F.F.; Ni, Y.X. [Department of Electrical and Electronic Engineering, The University of Hong Kong (China)


    In this paper, it is suggested that the preference of an individual consumer for its power supply reliability should be considered when scheduling the system reserve. The mechanism of 'provider insurance' is introduced and the reserve market is to be managed as an insurance system. In our modeling, the generator who provides the insurance of reliable power supply via its reserve, should always collect the payment (the premium), and be rewarded with the spot market price for its called reserve. The consumer who buys the insurance, pays premium and thus obtains a reliable power supply (the claim). It is argued that such a market mechanism will result in the maximum social welfare. Moreover, it is shown that there is a kind of 'moral hazard in reverse' fact that will further improve the market efficiency. Later on, discussions on implementing the proposed method are given, and an illustrative example is provided to show basic features of the proposed method. (author)

  12. Reliable Quantum Computers

    Preskill, J


    The new field of quantum error correction has developed spectacularly since its origin less than two years ago. Encoded quantum information can be protected from errors that arise due to uncontrolled interactions with the environment. Recovery from errors can work effectively even if occasional mistakes occur during the recovery procedure. Furthermore, encoded quantum information can be processed without serious propagation of errors. Hence, an arbitrarily long quantum computation can be performed reliably, provided that the average probability of error per quantum gate is less than a certain critical value, the accuracy threshold. A quantum computer storing about 10^6 qubits, with a probability of error per quantum gate of order 10^{-6}, would be a formidable factoring engine. Even a smaller, less accurate quantum computer would be able to perform many useful tasks. (This paper is based on a talk presented at the ITP Conference on Quantum Coherence and Decoherence, 15-18 December 1996.)

  13. Exact two-terminal reliability of some directed networks

    Tanguy, Christian


    The calculation of network reliability in a probabilistic context has long been an issue of practical and academic importance. Conventional approaches (determination of bounds, sums of disjoint products algorithms, Monte Carlo evaluations, studies of the reliability polynomials, etc.) only provide approximations when the network's size increases, even when nodes do not fail and all edges have the same reliability p. We consider here a directed, generic graph of arbitrary size mimicking real-life long-haul communication networks, and give the exact, analytical solution for the two-terminal reliability. This solution involves a product of transfer matrices, in which individual reliabilities of edges and nodes are taken into account. The special case of identical edge and node reliabilities (p and rho, respectively) is addressed. We consider a case study based on a commonly-used configuration, and assess the influence of the edges being directed (or not) on various measures of network performance. While the two-...

  14. Reliability-based Assessment of Fatigue Life for Bridges

    Toft, Henrik Stensgaard; Sørensen, John Dalsgaard


    The reliability level for bridges is discussed based on a comparison of the reliability levels proposed and used by e.g. JCSS, ISO, NKB and Eurocodes. The influence of reserve capacity by which failure of a specific detail does not lead to structural collapse is investigated. The results show...... of regular inspections into account. In an illustrative example the reliability level for a set of typical welded steel details is investigated along with the influence of different inspection methods. The results show that the reliability level can be significantly increased by applying regular inspections....... However, the accuracy of the inspection methods has a significant influence on how much the reliability level is increased by an inspection....

  15. 42 CFR 403.253 - Calculation of benefits.


    ... values on the initial calculation date of— (A) Expected incurred benefits in the loss ratio calculation period, to— (B) The total policy reserve at the last day of the loss ratio calculation period: and (ii... Ratio Provisions § 403.253 Calculation of benefits. (a) General provisions. (1) Except as provided...

  16. Evaluation of nodal reliability risk in a deregulated power system with photovoltaic power penetration

    Zhao, Qian; Wang, Peng; Goel, Lalit


    and customer reliability requirements are correlated with energy and reserve prices. Therefore a new method should be developed to evaluate the impacts of PV power on customer reliability and system reserve deployment in the new environment. In this study, a method based on the pseudo-sequential Monte Carlo......Owing to the intermittent characteristic of solar radiation, power system reliability may be affected with high photovoltaic (PV) power penetration. To reduce large variation of PV power, additional system balancing reserve would be needed. In deregulated power systems, deployment of reserves...... simulation technique has been proposed to evaluate the reserve deployment and customers' nodal reliability with high PV power penetration. The proposed method can effectively model the chronological aspects and stochastic characteristics of PV power and system operation with high computation efficiency...

  17. Demand Response as a System Reliability Resource

    Eto, Joseph H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Lewis, Nancy Jo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Watson, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Kiliccote, Sila [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Auslander, David [Univ. of California, Berkeley, CA (United States); Paprotny, Igor [Univ. of California, Berkeley, CA (United States); Makarov, Yuri [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)


    The Demand Response as a System Reliability Resource project consists of six technical tasks: • Task 2.1. Test Plan and Conduct Tests: Contingency Reserves Demand Response (DR) Demonstration—a pioneering demonstration of how existing utility load-management assets can provide an important electricity system reliability resource known as contingency reserve. • Task 2.2. Participation in Electric Power Research Institute (EPRI) IntelliGrid—technical assistance to the EPRI IntelliGrid team in developing use cases and other high-level requirements for the architecture. • Task 2.3. Research, Development, and Demonstration (RD&D) Planning for Demand Response Technology Development—technical support to the Public Interest Energy Research (PIER) Program on five topics: Sub-task 1. PIER Smart Grid RD&D Planning Document; Sub-task 2. System Dynamics of Programmable Controllable Thermostats; Sub-task 3. California Independent System Operator (California ISO) DR Use Cases; Sub-task 4. California ISO Telemetry Requirements; and Sub-task 5. Design of a Building Load Data Storage Platform. • Task 2.4. Time Value of Demand Response—research that will enable California ISO to take better account of the speed of the resources that it deploys to ensure compliance with reliability rules for frequency control. • Task 2.5. System Integration and Market Research: Southern California Edison (SCE)—research and technical support for efforts led by SCE to conduct demand response pilot demonstrations to provide a contingency reserve service (known as non-spinning reserve) through a targeted sub-population of aggregated residential and small commercial customers enrolled in SCE’s traditional air conditioning (AC) load cycling program, the Summer Discount Plan. • Task 2.6. Demonstrate Demand Response Technologies: Pacific Gas and Electric (PG&E)—research and technical support for efforts led by PG&E to conduct a demand response pilot demonstration to provide non

  18. Cognitive Reserve Scale and ageing

    Irene León


    Full Text Available The construct of cognitive reserve attempts to explain why some individuals with brain impairment, and some people during normal ageing, can solve cognitive tasks better than expected. This study aimed to estimate cognitive reserve in a healthy sample of people aged 65 years and over, with special attention to its influence on cognitive performance. For this purpose, it used the Cognitive Reserve Scale (CRS and a neuropsychological battery that included tests of attention and memory. The results revealed that women obtained higher total CRS raw scores than men. Moreover, the CRS predicted the learning curve, short-term and long-term memory, but not attentional and working memory performance. Thus, the CRS offers a new proxy of cognitive reserve based on cognitively stimulating activities performed by healthy elderly people. Following an active lifestyle throughout life was associated with better intellectual performance and positive effects on relevant aspects of quality of life.

  19. Ultrasound in evaluating ovarian reserve

    Eman Ahmaed Shawky Sabek; Ola I. Saleh; Howida A. Ahmed


    The objective of this study was to compare the diagnostic accuracy of transvaginal ultrasound (TVS), as a less invasive technique instead of hormonal assay to evaluate the ovarian reserve. This study included fifty-five females with breast cancer and we compared the ovarian reserve for these patients by hormonal assay through measuring the serum AntiMullerian Hormone (AMH) level and follicular stimulating hormone (FSH) level before and after chemotherapy, and by transvaginal ultrasound throug...

  20. Fractional Reserve Banking: Some Quibbles

    Bagus, Philipp; Howden, David


    We explore several unaddressed issues in George Selgin’s (1988) claim that the best monetary system to maintain monetary equilibrium is a fractional reserve free banking one. The claim that adverse clearing balances would limit credit expansion in a fractional reserve free banking system is more troublesome than previously reckoned. Both lengthened clearing periods and interbank agreements render credit expansion unrestrained. “The theory of free banking” confuses increases in money held with...

  1. Hybrid reliability model for fatigue reliability analysis of steel bridges

    曹珊珊; 雷俊卿


    A kind of hybrid reliability model is presented to solve the fatigue reliability problems of steel bridges. The cumulative damage model is one kind of the models used in fatigue reliability analysis. The parameter characteristics of the model can be described as probabilistic and interval. The two-stage hybrid reliability model is given with a theoretical foundation and a solving algorithm to solve the hybrid reliability problems. The theoretical foundation is established by the consistency relationships of interval reliability model and probability reliability model with normally distributed variables in theory. The solving process is combined with the definition of interval reliability index and the probabilistic algorithm. With the consideration of the parameter characteristics of theS−N curve, the cumulative damage model with hybrid variables is given based on the standards from different countries. Lastly, a case of steel structure in the Neville Island Bridge is analyzed to verify the applicability of the hybrid reliability model in fatigue reliability analysis based on the AASHTO.

  2. Electrical utility generating system reliability analysis code, SYSREL. Social cost studies program

    Hub, K.; Conley, L.; Buehring, W.; Rowland, B.; Stephenson, M.


    The system reliability code, SYSREL, is a system planning tool that can be used to assess the reliability and economic performance of alternative expansion patterns of electric utility generation systems. Given input information such as capacity, forced-outage rate, number of weeks of annual scheduled maintenance, and economic data for individual units along with the expected load characteristics, the code produces estimates of the mean time between system failures, required reserve capacity to meet a specified system-failure-frequency criterion, expected energy generation from each unit, and system energy cost. The categories of calculations performed by the code are maintenance scheduling, reliability, capacity requirement, energy production allocation, and energy cost. The code is designed to examine alternative generating units and system expansion patterns based on the constraints and general economic conditions imposed by the investigator. The computer running time to execute a study is short and many system alternatives can be examined at a relatively low cost. The report contains a technical description of the code, list of input data requirements, program listing, sample execution, and parameter studies. (auth)

  3. The Motivational Interviewing Treatment Integrity Code (MITI 4): Rationale, Preliminary Reliability and Validity.

    Moyers, Theresa B; Rowell, Lauren N; Manuel, Jennifer K; Ernst, Denise; Houck, Jon M


    The Motivational Interviewing Treatment Integrity code has been revised to address new evidence-based elements of motivational interviewing (MI). This new version (MITI 4) includes new global ratings to assess clinician's attention to client language, increased rigor in assessing autonomy support and client choice, and items to evaluate the use of persuasion when giving information and advice. Four undergraduate, non-professional raters were trained in the MITI and used it to review 50 audiotapes of clinicians conducting MI in actual treatments sessions. Both kappa and intraclass correlation indices were calculated for all coders, for the best rater pair and for a 20% randomly selected sample from the best rater pair. Reliability across raters, with the exception of Emphasize Autonomy and % Complex Reflections, were in the good to excellent range. Reliability estimates decrease when smaller samples are used and when fewer raters contribute. The advantages and drawbacks of this revision are discussed including implications for research and clinical applications. The MITI 4.0 represents a reliable method for assessing the integrity of MI including both the technical and relational components of the method. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. The validity and reliability of computed tomography orbital volume measurements.

    Diaconu, Silviu C; Dreizin, David; Uluer, Mehmet; Mossop, Corey; Grant, Michael P; Nam, Arthur J


    Orbital volume calculations allow surgeons to design patient-specific implants to correct volume deficits. It is estimated that changes as small as 1 ml in orbital volume can lead to enophthalmos. Awareness of the limitations of orbital volume computed tomography (CT) measurements is critical to differentiate between true volume differences and measurement error. The aim of this study is to analyze the validity and reliability of CT orbital volume measurements. A total of 12 cadaver orbits were scanned using a standard CT maxillofacial protocol. Each orbit was dissected to isolate the extraocular muscles, fatty tissue, and globe. The empty bony orbital cavity was then filled with sculpting clay. The volumes of the muscle, fat, globe, and clay (i.e., bony orbital cavity) were then individually measured via water displacement. The CT-derived volumes, measured by manual segmentation, were compared to the direct measurements to determine validity. The difference between CT orbital volume measurements and physically measured volumes is not negligible. Globe volumes have the highest agreement with 95% of differences between -0.5 and 0.5 ml, bony volumes are more likely to be overestimated with 95% of differences between -1.8 and 2.6 ml, whereas extraocular muscle volumes have poor validity and should be interpreted with caution. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.


    Moroz N. Y.


    Full Text Available This article is dedicated to the methods of calculation and the accounts’ reflection of the depreciation reserves. The methods are differentiated on the method of depreciation calculation

  6. Synthesis of Reliable Telecommunication Networks

    Dusan Trstensky


    Full Text Available In many application, the network designer may to know to senthesise a reliable telecommunication network. Assume that a network, denoted Gm,e has the number of nodes n and the number of edges e, and the operational probability of each edge is known. The system reliability of the network is defined to be the reliability that every pair of nodes can communicate with each other. A network synthesis problem considered in this paper is to find a network G*n,e, that maximises system reliability over the class of all networks for the classes of networks Gn,n-1, Gn,m and Gn,n+1 respectively. In addition an upper bound of maximum reliability for the networks with n-node and e-edge (e>n+2 is derived in terms of node. Computational experiments for the reliability upper are also presented. the results show, that the proposed reliability upper bound is effective.

  7. Mathematical reliability an expository perspective

    Mazzuchi, Thomas; Singpurwalla, Nozer


    In this volume consideration was given to more advanced theoretical approaches and novel applications of reliability to ensure that topics having a futuristic impact were specifically included. Topics like finance, forensics, information, and orthopedics, as well as the more traditional reliability topics were purposefully undertaken to make this collection different from the existing books in reliability. The entries have been categorized into seven parts, each emphasizing a theme that seems poised for the future development of reliability as an academic discipline with relevance. The seven parts are networks and systems; recurrent events; information and design; failure rate function and burn-in; software reliability and random environments; reliability in composites and orthopedics, and reliability in finance and forensics. Embedded within the above are some of the other currently active topics such as causality, cascading, exchangeability, expert testimony, hierarchical modeling, optimization and survival...

  8. [Interrater reliability of the Braden scale].

    Kottner, Jan; Tannen, Antje; Dassen, Theo


    Pressure ulcer risk assessment scales can assist nurses in determining the individual pressure ulcer risk. Although the Braden scale is widely used throughout Germany, its psychometric properties are yet unknown. The aim of the study was to determine the interrater reliability of the Braden scale and to compare the results with those of published data. A literature review was conducted. 20 studies measuring the interrater reliability of the Braden scale were evaluated. Only three of those studies investigated the interrater reliability of single items. The Pearson product-moment correlation coefficient (0.80 to 1.00) was calculated in most studies for an evaluation of the Braden scale as a whole. However, the use of correlation coefficients is inappropriate for measuring the interrater reliability of the Braden scale. Measures of the intraclass correlation coefficient varied from 0.83 to 0.99. The investigation of the interrater reliability of the Braden scale's German version was conducted in a German nursing home in 2006. Nurses independently rated 18 and 32 residents twice. Nurses achieved the highest agreement when rating the items "friction and shear" and "activity" (overall proportion of agreement = 0.67 to 0.84, Cohen's Kappa = 0.57 to 0.73). The lowest agreement was achieved when the item "nutrition" (overall proportion of agreement = 0.47 to 0.51, Cohen's Kappa = 0.28 to 0.30) was rated. For 66% of the rated residents the difference in the obtained Braden scores was equal or less than one point. Intraclass correlation coefficients were 0.91 (95% confidence interval 0.82 to 0.96) and 0.88 (95% confidence interval 0.61 to 0.96). This indicates that the interrater reliability of the Braden scale was high in the examined setting.

  9. Assessment of hepatic functional reserve by converted asialoglycoprotein receptor values calculated from parameters of indocyanine green test and thromboelastograph%应用吲哚青绿试验与血栓弹力图替代去唾液酸糖蛋白受体分析定量评估肝储备功能

    张珂; 郭立民; 穆毅; 蒋力; 贾哲; 李宝亮; 赫嵘; 黄容海; 鲁岩; 李勤涛; 丁振昊


    目的:应用吲哚青绿实验与血栓弹力图检测指标,替代肝细胞表面去唾液酸糖蛋白受体分析,建立肝储备功能定量评估系统,并与Child-Pugh评分进行比较,了解其在肝切除术患者肝储备功能评估中的临床应用价值。方法对2012年1月1日至12月31日于本科室行肝部分切除术肝占位病变的患者共55例,测量PHCASGPR+、ICGR15、EHBF、R值与K值,建立以PHCASGPR+为因变量(Y), ICGR15、EHBF、R值与K值为自变量(Xn)的肝储备功能定量评估系统,与Child-Pugh评分进行比较,了解两种方法预测术后肝功能代偿情况的准确率。结果 Child-Pugh预测术后肝功能代偿良好准确率为56.67%,Y值预测术后肝功能代偿良好准确率为84.62%(χ2=5.374,P =0.020);Child-Pugh预测术后肝功能代偿不全准确率为76.00%,Y值预测术后肝功能代偿不全准确率为96.55%(χ2=5.400,P =0.020)。结论建立的肝储备功能定量评估系统能够更全面评价肝切除患者围手术期肝储备功能。%Objective To verify the value of asialoglycoprotein receptors (ASGPR) analyzed by lfow cytometry (FCM) in assessing hepatic functional reserve, and establish a conversion formula for the ASGPR value with the parameters of indocyanine green (ICG) test and thromboelastography (TEG). This assessment method was compared with the Child-Pugh score to evaluate its predictive value for hepatic functional reserve in patients undergoing liver resection.Methods Total of 55 patients with liver tumors had partial hepatectomy in our department from January 1st to December 31st, 2012. The percentages of ASGPR+hepatocyte (PHCASGPR+), ICGR15, effective hepatic blood lfow (EHBF), R value and K value were examined to establish the quantitative assessment method for liver functional reserve. The PHCASGPR+ was defined as a dependent variable (Y) while the ICGR15, EHBF, R value and K value were defined as independent variables

  10. Reliability analysis of ship structure system with multi-defects


    This paper analyzes the influence of multi-defects including the initial distortions,welding residual stresses,cracks and local dents on the ultimate strength of the plate element,and has worked out expressions of reliability calculation and sensitivity analysis of the plate element.Reliability analysis is made for the system with multi-defects plate elements.Failure mechanism,failure paths and the calculating approach to global reliability index are also worked out.After plate elements with multi-defects fail,the formula of reverse node forces which affect the residual structure is deduced,so are the sensitivity expressions of the system reliability index.This ensures calculating accuracy and rationality for reliability analysis,and makes it convenient to find weakness plate elements which affect the reliability of the structure system.Finally,for the validity of the approach proposed,we take the numerical example of a ship cabin to compare and contrast the reliability and the sensitivity analysis of the structure system with multi-defects with those of the structure system with no defects.The approach has implications for the structure design,rational maintenance and renewing strategy.

  11. Calculation Methods for Wallenius’ Noncentral Hypergeometric Distribution

    Fog, Agner


    distribution are derived. Range of applicability, numerical problems, and efficiency are discussed for each method. Approximations to the mean and variance are also discussed. This distribution has important applications in models of biased sampling and in models of evolutionary systems....... is the conditional distribution of independent binomial variates given their sum. No reliable calculation method for Wallenius' noncentral hypergeometric distribution has hitherto been described in the literature. Several new methods for calculating probabilities from Wallenius' noncentral hypergeometric...

  12. Optimized Vertex Method and Hybrid Reliability

    Smith, Steven A.; Krishnamurthy, T.; Mason, B. H.


    A method of calculating the fuzzy response of a system is presented. This method, called the Optimized Vertex Method (OVM), is based upon the vertex method but requires considerably fewer function evaluations. The method is demonstrated by calculating the response membership function of strain-energy release rate for a bonded joint with a crack. The possibility of failure of the bonded joint was determined over a range of loads. After completing the possibilistic analysis, the possibilistic (fuzzy) membership functions were transformed to probability density functions and the probability of failure of the bonded joint was calculated. This approach is called a possibility-based hybrid reliability assessment. The possibility and probability of failure are presented and compared to a Monte Carlo Simulation (MCS) of the bonded joint.

  13. Overview of RELCOMP, the reliability and cost model for electrical generation planning

    Buehring, W.A.; Hub, K.A.; VanKuiken, J.C.


    RELCOMP is a system-planning tool that can be used to assess the reliability and economic performance of alternative expansion patterns of electric-utility-generating systems. Given input information such as capacity, forced outage rate, number of weeks of annual scheduled maintenance, and economic data for individual units along with the expected utility load characteristics, the nonoptimizing model calculates a system maintenance schedule, the loss-of-load probability, unserved demand for energy, mean time between system failures to meet the load, required reserve to meet a specified system-failure rate, expected energy generation from each unit, and system energy cost. Emergency interties and firm purchases can be included in the analysis. The calculation can be broken down into five distinct categories: maintenance scheduling, system reliability, capacity requirement, energy allocation, and energy cost. This brief description of the program is intended to serve as preliminary documentation for RELCOMP until a more-complete documentation is prepared. In addition to this documentation, a sample problem and a detailed input description are available from the authors.

  14. Demand as frequency controlled reserve

    Xu, Z.; Togeby, M.; OEstergaard, J.


    Using demand as frequency controlled reserve (DFR) is an emerging technology which allow demand to participate actively in maintaining the system operation without reducing the energy service delivered to the customer and without need of user interaction. The basic premise is that traditional frequency controlled reserves from power plants and interconnections with neighbouring systems can be costly, slow and not fulfil the need for future power grids with a high share of wind power and fewer central power plants, and an intention to perform flexible operation such as is landing. Electricity demands, on the other hand, have advantages as frequency reserve including fast activation speed, smooth linear activation, low expected costs, and well-dispersed in the distribution grid. The main challenge of DFR is new methods for monitoring the available capacity. This project has investigated the technology of using electricity demands for providing frequency reserve to power systems. Within the project the potential and economy of DFR compatible loads in Denmark has been investigated, control logic has been designed, power system impact has been investigated, potential business models has been evaluated and an implementation strategy has been suggested. The tasks and goals of the project have been successfully accomplished based on which the conclusion and future recommendation are made. This project has developed the DFR technology that enables electricity demands to autonomously disconnect or reconnect to the grid in response to system frequency variations. The developed DFR technology is proved to be a promising technology from several perspectives. Technically, using DFR is feasible to provide reserves and enhance power system frequency control, while fulfilling technical requirements such as linear activation (or reconnection) according to frequency (or time). Environmentally, the DFR technology is pollution free in contrast to traditional reserves from generation

  15. Magnetic Field Calculator

    National Oceanic and Atmospheric Administration, Department of Commerce — The Magnetic Field Calculator will calculate the total magnetic field, including components (declination, inclination, horizontal intensity, northerly intensity,...

  16. On One Possibility to Improve Reliability of Magnetic Starter

    V. Anishchenko


    Full Text Available The paper proposes and considers a possibility to improve an operational reliability of reversing magnetic starters by reservation of main and auxiliary contacts in accordance with majority-logic voter «two out of three».

  17. Reliability analysis of wastewater treatment plants.

    Oliveira, Sílvia C; Von Sperling, Marcos


    This article presents a reliability analysis of 166 full-scale wastewater treatment plants operating in Brazil. Six different processes have been investigated, comprising septic tank+anaerobic filter, facultative pond, anaerobic pond+facultative pond, activated sludge, upflow anaerobic sludge blanket (UASB) reactors alone and UASB reactors followed by post-treatment. A methodology developed by Niku et al. [1979. Performance of activated sludge process and reliability-based design. J. Water Pollut. Control Assoc., 51(12), 2841-2857] is used for determining the coefficients of reliability (COR), in terms of the compliance of effluent biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP) and fecal or thermotolerant coliforms (FC) with discharge standards. The design concentrations necessary to meet the prevailing discharge standards and the expected compliance percentages have been calculated from the COR obtained. The results showed that few plants, under the observed operating conditions, would be able to present reliable performances considering the compliance with the analyzed standards. The article also discusses the importance of understanding the lognormal behavior of the data in setting up discharge standards, in interpreting monitoring results and compliance with the legislation.

  18. Reliability Evaluation Method for IP Multicast Communication under QoS Constraints

    Dai Fusheng; Bao Xuecai; Han Weizhan


    In order to estimate the reliability performance of multicast communication under multiple constraint conditions,the weight of service rate and the reliability index are defined,accompanying the calculation method.Firstly,according to the Quality of Service requirements,the appropriate routings between the central node and target nodes that meet the requirements are calculated using the iterative method in the weighted internet.Then,the disjoint set of network state and the coefficients of weighted service rate are calculated by decomposition and merge methods.Lastly,the formula for calculating the service rate is obtained based on the disjoint set of network state and the calculation of the reliability index will be completed.The simulation result shows that the reliability of multicast communication can be appropriately reflected by the weight of service rate and the calculation method,which can provide the theoretical basis for the reliability evaluation of multicast communication.

  19. The Coal Reserves Database Program

    Bonskowski, R. (Energy Information Administration, Washington, DC (United States))


    The Energy Information Administration (EIA) initiated the Coal Reserves Data Base (CRDB) Program in October, 1990 in order to update and improve the inherent applicability of EIA's national coal reserves database. Currently, EIA's database is derived from the demonstrated reserve base (DRB) of coal, a compilation of data from published sources, unified by adherence to standardized physical criteria of minability, but never intended for the detailed coal supply and policy analyses demanded today. The CRDB Program is designed to engage the expertise available at State geological surveys in compiling best current State-level estimates of both quantities and quality of available coal reserves through cooperative agreements with EIA. The CRDB emphasizes integration of more data on coal quality, use of data from unpublished sources, cooperation with industry and other government sources, and flexibility of criteria to take into account local accessibility and mining conditions and utilize computerized geographic information systems or coal resource software. The results of pilot projects in Ohio and Wyoming are summarized. Areas nominated for support in the program include 15 additional priority coal regions in 14 States, which comprise 95 percent of the current reserve estimates and most of the coal-bearing areas of low sulfur potential. 8 refs., 3 figs., 3 tabs.

  20. Molecular Dynamics Calculations


    The development of thermodynamics and statistical mechanics is very important in the history of physics, and it underlines the difficulty in dealing with systems involving many bodies, even if those bodies are identical. Macroscopic systems of atoms typically contain so many particles that it would be virtually impossible to follow the behavior of all of the particles involved. Therefore, the behavior of a complete system can only be described or predicted in statistical ways. Under a grant to the NASA Lewis Research Center, scientists at the Case Western Reserve University have been examining the use of modern computing techniques that may be able to investigate and find the behavior of complete systems that have a large number of particles by tracking each particle individually. This is the study of molecular dynamics. In contrast to Monte Carlo techniques, which incorporate uncertainty from the outset, molecular dynamics calculations are fully deterministic. Although it is still impossible to track, even on high-speed computers, each particle in a system of a trillion trillion particles, it has been found that such systems can be well simulated by calculating the trajectories of a few thousand particles. Modern computers and efficient computing strategies have been used to calculate the behavior of a few physical systems and are now being employed to study important problems such as supersonic flows in the laboratory and in space. In particular, an animated video (available in mpeg format--4.4 MB) was produced by Dr. M.J. Woo, now a National Research Council fellow at Lewis, and the G-VIS laboratory at Lewis. This video shows the behavior of supersonic shocks produced by pistons in enclosed cylinders by following exactly the behavior of thousands of particles. The major assumptions made were that the particles involved were hard spheres and that all collisions with the walls and with other particles were fully elastic. The animated video was voted one of two

  1. What's working, what's not: The monitoring and reporting system for Tasmania's national parks and reserves

    Glenys Jones


    This paper describes the Australian State of Tasmania's management effectiveness Monitoring and Reporting System for national parks and reserves. This jurisdictional performance measurement system is designed to provide all interested parties with reliable factual information and measured evidence about reserve management achievements, progress and challenges. Key...

  2. Tubular stabilizer bars – calculations and construction

    Adam-Markus WITTEK


    Full Text Available The article outlines the calculation methods for tubular stabilizer bars. Modern technological and structural solutions in contemporary cars are reflected also in the construction, selection and manufacturing of tubular stabilizer bars. A proper construction and the selection of parameters influence the strength properties, the weight, durability and reliability as well as the selection of an appropriate production method.

  3. Stabilizer bars: Part 1. Calculations and construction

    Adam-Markus WITTEK


    Full Text Available The article outlines the calculation methods for stabilizer bars. Modern technological and structural solutions in contemporary cars are reflected also in the construction and manufacturing of stabilizer bars. A proper construction and the selection of parameters influence the strength properties, the weight, durability and reliability as well as the selection of an appropriate production method.

  4. Distribution Equipment Reliability Data; Tillfoerlitlighetsdata paa komponent nivaa foer eldistributionsnaet

    Ying He (Vattenfall Research and Development AB, Stockholm (SE))


    In risk analysis of a power system, the risk for the system to fail power supply is calculated from the knowledge of the reliability data of individual system components. Meaningful risk analysis requires reasonable and acceptable data. The quality of the data has the fundamental importance for the analysis. However, the valid data are expensive to collect. The component reliability performance statistics are not easy to obtain. This report documents the distribution equipment reliability data developed by the project 'Component Reliability Data for Risk Analysis of Distribution Systems' within the Elforsk RandD program 'Risk Analysis 06-10'. The project analyzed a large sample size of distribution outages recorded by more than a hundred power utilities in Sweden during 2004-2005, and derived the equipment reliability data nationwide. The detailed summaries of these data are presented in the appendices of the report. The component reliability was also investigated at a number of power utilities including Vattenfall Eldistribution AB, Goeteborg Energi Naet AB, E.ON Elnaet Sverige AB, Fortum Distribution, and Linde Energi AB. The reliability data were derived for individual utilities. The detailed data lists and failure statistics are summarized in the appendices for each participating companies. The data provided in this report are developed based on a large sample size of field outage records and can be therefore used as generic data in system risk analysis and reliability studies. In order to provide more references and complementary data, the equipment reliability surveys conducted by IEEE were studied in the project. The most significant results obtained by the IEEE surveys are provided in the report. A summary of the reliability data surveyed by IEEE is presented in the appendix of the report. These data are suggested to use in the absence of better data being available. The reliability data estimates were derived for sustained failure rates

  5. Leveraging the Reserve Component: Associating Active and Reserve Aviation Units


    capabilities, forces for large-scale conventional campaigns, balance stress across the Total Force, include a larger portion of American citizenry defending...Integration will also relieve stress on the Active Duty force and provide a cost-effective force multiplier. Finally, it will leverage the high...heavily.18 Other identified organizational challenges included cross- acculturation between active and reserve component career

  6. Reactive Power Compensation Method Considering Minimum Effective Reactive Power Reserve

    Gong, Yiyu; Zhang, Kai; Pu, Zhang; Li, Xuenan; Zuo, Xianghong; Zhen, Jiao; Sudan, Teng


    According to the calculation model of minimum generator reactive power reserve of power system voltage stability under the premise of the guarantee, the reactive power management system with reactive power compensation combined generator, the formation of a multi-objective optimization problem, propose a reactive power reserve is considered the minimum generator reactive power compensation optimization method. This method through the improvement of the objective function and constraint conditions, when the system load growth, relying solely on reactive power generation system can not meet the requirement of safe operation, increase the reactive power reserve to solve the problem of minimum generator reactive power compensation in the case of load node.

  7. Hydrocarbon Reserves: Abundance or Scarcity



    IFP and the OAPEC jointly organize a regular international seminar dealing with world oil-related problems appearing in the news. For the first time, this seminar has been opened to oil and gas company specialists, service companies, research centers and independents. This year's theme concerns oil and gas reserves: are they abundant or are we headed towards the shortages announced by some experts? This theme is especially topical in that: oil and gas currently meet two thirds of world energy needs and almost completely dominate the transport sector; the reserves declared by the OAPEC countries account for nearly half of world reserves; the price of a barrel of oil went through the roof in 2004; world energy demand is growing fast and alternative sources of energy are far from ready to take over from oil and gas in the next few decades. Since the reserves correspond to the volume it is technically and economically viable to produce, the seminar has, of course, dealt with the technical and economic questions that arise in connection with exploration and production, but it has also considered changes in the geopolitical context. Presentations by the leading companies of the OAPEC countries and by the IFP group were completed by presentation from the International Energy Agency (IEA), the United States Geological Survey (USGS), the IHS Energy Group, Total and Gaz de France. This document gathers the transparencies of the following presentations: Hydrocarbon reserves in OAPEC members countries: current and future (M. Al-Lababidi); Non OAPEC liquid reserves and production forecasts (Y. Mathieu); World oil and gas resources and production outlook (K. Chew); Global investments in the upstream (F. Birol); Total's policy in the oil and gas sector (C. de Margerie); Gaz de France's policy in the oil and gas sector (J. Abiteboul); NOC/IOC's opportunities in OPEC countries (I. Sandrea); Relationships between companies, countries and investors: How they may

  8. Cognitive reserve: The warehouse within

    Jyoti Prakash


    Full Text Available Dementia is characterized by progressive and mostly irreversible memory loss. Other neuropsychiatric disorders affect cognition in varying manner. Are all people affected with such disorders manifest clinically in similar manner or does our brain have some reserve to tolerate insults? Relevant researches over the last two decades were scrutinized to understand brain reserve, appreciate the conceptual change in the same over years, and how the same can be improved for better cognition and memory over the year. Literature evidence suggests that the cognitive reserve (CR is a dynamic and functional concept. There is adequate evidence to suggest that enriched environment and various other measures are likely to improve CR across all age. Improving CR may delay or reverse the effects of aging or brain pathology.

  9. Reliability Assessment Of Wind Turbines

    Sørensen, John Dalsgaard


    Reduction of cost of energy for wind turbines are very important in order to make wind energy competitive compared to other energy sources. Therefore the turbine components should be designed to have sufficient reliability but also not be too costly (and safe). This paper presents models...... for uncertainty modeling and reliability assessment of especially the structural components such as tower, blades, substructure and foundation. But since the function of a wind turbine is highly dependent on many electrical and mechanical components as well as a control system also reliability aspects...... of these components are discussed and it is described how there reliability influences the reliability of the structural components. Two illustrative examples are presented considering uncertainty modeling, reliability assessment and calibration of partial safety factors for structural wind turbine components exposed...

  10. Nuclear weapon reliability evaluation methodology

    Wright, D.L. [Sandia National Labs., Albuquerque, NM (United States)


    This document provides an overview of those activities that are normally performed by Sandia National Laboratories to provide nuclear weapon reliability evaluations for the Department of Energy. These reliability evaluations are first provided as a prediction of the attainable stockpile reliability of a proposed weapon design. Stockpile reliability assessments are provided for each weapon type as the weapon is fielded and are continuously updated throughout the weapon stockpile life. The reliability predictions and assessments depend heavily on data from both laboratory simulation and actual flight tests. An important part of the methodology are the opportunities for review that occur throughout the entire process that assure a consistent approach and appropriate use of the data for reliability evaluation purposes.

  11. Reliability engineering theory and practice

    Birolini, Alessandro


    This book shows how to build in, evaluate, and demonstrate reliability and availability of components, equipment, systems. It presents the state-of-theart of reliability engineering, both in theory and practice, and is based on the author's more than 30 years experience in this field, half in industry and half as Professor of Reliability Engineering at the ETH, Zurich. The structure of the book allows rapid access to practical results. This final edition extend and replace all previous editions. New are, in particular, a strategy to mitigate incomplete coverage, a comprehensive introduction to human reliability with design guidelines and new models, and a refinement of reliability allocation, design guidelines for maintainability, and concepts related to regenerative stochastic processes. The set of problems for homework has been extended. Methods & tools are given in a way that they can be tailored to cover different reliability requirement levels and be used for safety analysis. Because of the Appendice...

  12. The Antipsychotics and Sexual Functioning Questionnaire (ASFQ) : Preliminary evidence for reliability and validity

    de Boer, M.K.; Castelein, Stynke; Bous, Johan; van den Heuvel, Edwin R.; Wiersma, Durk; Schoevers, Robert A.; Knegtering, Henderikus


    The aim of this study is to describe the psychometric properties of the Antipsychotics and Sexual Functioning Questionnaire (ASFQ). Internal reliability, test-retest reliability, inter-rater reliability, validity and sensitivity to change were calculated in a sample of 30 patients with schizophrenia

  13. The Antipsychotics and Sexual Functioning Questionnaire (ASFQ) : preliminary evidence for reliability and validity

    de Boer, Marrit K; Castelein, Stynke; Bous, Johan; van den Heuvel, Edwin R; Wiersma, Durk; Schoevers, Robert A; Knegtering, Henderikus


    The aim of this study is to describe the psychometric properties of the Antipsychotics and Sexual Functioning Questionnaire (ASFQ). Internal reliability, test-retest reliability, inter-rater reliability, validity and sensitivity to change were calculated in a sample of 30 patients with schizophrenia

  14. Reliability Generalization of Curriculum-Based Measurement Reading Aloud: A Meta-Analytic Review

    Yeo, Seungsoo


    The purpose of this study was to employ the meta-analytic method of Reliability Generalization to investigate the magnitude and variability of reliability estimates obtained across studies using Curriculum-Based Measurement reading aloud. Twenty-eight studies that met the inclusion criteria were used to calculate the overall mean reliability of…

  15. Service reliability in a network context: Impacts of synchronizing schedules in long headway services

    Lee, A.; Van Oort, N.; Van Nes, R.


    This paper presents research on synchronization of transfers and its impact on service reliability from a passenger perspective. Passenger reliability is analyzed for the case of a multi-operator transfer node. A method is developed to calculate the passenger centered reliability indicators: addi

  16. Reliability Analysis of Elasto-Plastic Structures


    . Failure of this type of system is defined either as formation of a mechanism or by failure of a prescribed number of elements. In the first case failure is independent of the order in which the elements fail, but this is not so by the second definition. The reliability analysis consists of two parts...... are described and the two definitions of failure can be used by the first formulation, but only the failure definition based on formation of a mechanism by the second formulation. The second part of the reliability analysis is an estimate of the failure probability for the structure on the basis...... are obtained if the failure mechanisms are used. Lower bounds can be calculated on the basis of series systems where the elements are the non-failed elements in a non-failed structure (see Augusti & Baratta [3])....

  17. Reliability analysis of ceramic matrix composite laminates

    Thomas, David J.; Wetherhold, Robert C.


    At a macroscopic level, a composite lamina may be considered as a homogeneous orthotropic solid whose directional strengths are random variables. Incorporation of these random variable strengths into failure models, either interactive or non-interactive, allows for the evaluation of the lamina reliability under a given stress state. Using a non-interactive criterion for demonstration purposes, laminate reliabilities are calculated assuming previously established load sharing rules for the redistribution of load as the failure of laminae occur. The matrix cracking predicted by ACK theory is modeled to allow a loss of stiffness in the fiber direction. The subsequent failure in the fiber direction is controlled by a modified bundle theory. Results using this modified bundle model are compared with previous models which did not permit separate consideration of matrix cracking, as well as to results obtained from experimental data.

  18. Overcoming some limitations of imprecise reliability models

    Kozine, Igor; Krymsky, Victor


    The application of imprecise reliability models is often hindered by the rapid growth in imprecision that occurs when many components constitute a system and by the fact that time to failure is bounded from above. The latter results in the necessity to explicitly introduce an upper bound on time...... to failure which is in reality a rather arbitrary value. The practical meaning of the models of this kind is brought to question. We suggest an approach that overcomes the issue of having to impose an upper bound on time to failure and makes the calculated lower and upper reliability measures more precise....... The main assumption consists in that failure rate is bounded. Langrage method is used to solve the non-linear program. Finally, an example is provided....

  19. Reliability assessment of underground shaft closure

    Fossum, A.F. [RE/SPEC, Inc., Rapid City, SD (United States); Munson, D.E. [Sandia National Labs., Albuquerque, NM (United States)


    The intent of the WIPP, being constructed in the bedded geologic salt deposits of Southeastern New Mexico, is to provide the technological basis for the safe disposal of radioactive Transuranic (TRU) wastes generated by the defense programs of the United States. In determining this technological basis, advanced reliability and structural analysis techniques are used to determine the probability of time-to-closure of a hypothetical underground shaft located in an argillaceous salt formation and filled with compacted crushed salt. Before being filled with crushed salt for sealing, the shaft provides access to an underground facility. Reliable closure of the shaft depends upon the sealing of the shaft through creep closure and recompaction of crushed backfill. Appropriate methods are demonstrated to calculate cumulative distribution functions of the closure based on laboratory determined random variable uncertainty in salt creep properties.

  20. Assessment of the reliability and consistency of the "malnutrition inflammation score" (MIS) in Mexican adults with chronic kidney disease for diagnosis of protein-energy wasting syndrome (PEW).

    González-Ortiz, Ailema Janeth; Arce-Santander, Celene Viridiana; Vega-Vega, Olynka; Correa-Rotter, Ricardo; Espinosa-Cuevas, María de Los Angeles


    The protein-energy wasting syndrome (PEW) is a condition of malnutrition, inflammation, anorexia and wasting of body reserves resulting from inflammatory and non-inflammatory conditions in patients with chronic kidney disease (CKD).One way of assessing PEW, extensively described in the literature, is using the Malnutrition Inflammation Score (MIS). To assess the reliability and consistency of MIS for diagnosis of PEW in Mexican adults with CKD on hemodialysis (HD). Study of diagnostic tests. A sample of 45 adults with CKD on HD were analyzed during the period June-July 2014.The instrument was applied on 2 occasions; the test-retest reliability was calculated using the Intraclass Correlation Coefficient (ICC); the internal consistency of the questionnaire was analyzed using Cronbach's αcoefficient. A weighted Kappa test was used to estimate the validity of the instrument; the result was subsequently compared with the Bilbrey nutritional index (BNI). The reliability of the questionnaires, evaluated in the patient sample, was ICC=0.829.The agreement between MIS observations was considered adequate, k= 0.585 (p MIS has adequate reliability and validity for diagnosing PEW in the population with chronic kidney disease on HD. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  1. Lithium battery safety and reliability

    Levy, Samuel C.

    Lithium batteries have been used in a variety of applications for a number of years. As their use continues to grow, particularly in the consumer market, a greater emphasis needs to be placed on safety and reliability. There is a useful technique which can help to design cells and batteries having a greater degree of safety and higher reliability. This technique, known as fault tree analysis, can also be useful in determining the cause of unsafe behavior and poor reliability in existing designs.

  2. Fatigue reliability of cracked engineering structures

    Lanning, David Bruce, Jr.


    This study investigates the reliability of engineering structures containing fatigue cracks. Stress concentrations and welded joints are probable locations for the initiation and propagation of fatigue cracks. Due to the many unknowns of loading, materials properties, crack sizes and crack shapes present at these locations, a statistics-based reliability analysis is valuable in the careful consideration of these many different random factors involved in a fatigue life analysis, several of which are expanded upon in this study. The basic problem of a crack near a stress concentration is first considered. A formulation for the aspect ratio (a/c) of a propagating semi-elliptical fatigue crack located at the toe of a welded T-joint is developed using Newman and Raju's stress intensity factor for a cracked flat plate with a weld magnification factor and compared to that of a cracked flat plate, and the reliability in terms of fatigue lifetime is calculated with the aid of Paris' crack propagation equation for membrane and bending loadings. Crack closure effects are then introduced in the consideration of short crack effects, where crack growth rates typically may exceed those found using traditional linear elastic fracture mechanics solutions for long cracks. The probability of a very small, microstructurally influenced crack growing to a size influenced by local plastic conditions is calculated utilizing the probability of a crack continuing to grow past an obstacle, such as a grain boundary. The result is then combined with the probability for failure defined using the crack closure-modified Paris equation to find an overall reliability for the structure. Last, the probability of fracture is determined when a crack front encounters regions of non-uniform toughness, such as typical in the heat affected zone of a welded joint. An expression for the effective crack lengths of the dissimilar regions is derived, and used in a weakest-link fracture model in the evaluation

  3. VO2 Reserve vs. Heart Rate Reserve During Moderate Intensity Treadmill Exercise.

    Solheim, Tanner J; Keller, Brad G; Fountaine, Charles J

    VO2 and heart rate (HR) are widely used when determining appropriate training intensities for clinical, healthy, and athletic populations. It has been shown that if the % reserve (%R) is used, rather than % of max, HR and VO2 can be used interchangeably to accurately prescribe exercise intensities. Thus, heart rate reserve (HRR) can be prescribed if VO2 reserve (VO2R) is known. Therefore, the purpose of this study was to compare VO2 R and HRR during moderate intensity exercise (50%R). Physically active college students performed a maximal treadmill test to exhaustion. During which VO2 and HR were monitored to determine max values. Upon completion of the maximal test, calculations were made to determine the % grade expected to yield approximately 50% of the subjects VO2R. Subjects then returned to complete the submaximal test (50%R) at least two days later. The %VO2R and %HRR were calculated and compared to the predicted value as well as to each other. Statistical analysis revealed that VO2 at 50%R was significantly greater than the actual VO2 achieved, p VO2 could be more accurately predicted than HR during moderate intensity exercise. The weak correlation between VO2R and HRR indicates that caution should be used when relying on a HR to determine VO2.

  4. Strategic petroleum reserve annual report



    Section 165 of the Energy Policy and Conservation Act (Public Law 94- 163), as amended, requires the Secretary of Energy to submit annual reports to the President and the Congress on activities of the Strategic Petroleum Reserve (SPR). This report describes activities for the year ending December 31, 1995.

  5. FEA Reports on Proved Reserves

    Geotimes, 1975


    Explains the way in which oil and gas reserves are estimated, and the variation in these estimates according to the year of the resources' estimation and the group undertaking the survey. A recent Federal Energy Administration study suggests that recoverable oil and gas resources have limits that may be approached in the next 50 years. (MLH)

  6. Demand as Frequency Controlled Reserve

    Xu, Zhao; Østergaard, Jacob; Togeby, Mikael


    Relying on generation side alone is deemed insufficient to fulfill the system balancing needs for future Danish power system, where a 50% wind penetration is outlined by the government for year 2025. This paper investigates using the electricity demand as frequency controlled reserve (DFR) as a new...

  7. A Reliability Based Model for Wind Turbine Selection

    A.K. Rajeevan


    Full Text Available A wind turbine generator output at a specific site depends on many factors, particularly cut- in, rated and cut-out wind speed parameters. Hence power output varies from turbine to turbine. The objective of this paper is to develop a mathematical relationship between reliability and wind power generation. The analytical computation of monthly wind power is obtained from weibull statistical model using cubic mean cube root of wind speed. Reliability calculation is based on failure probability analysis. There are many different types of wind turbinescommercially available in the market. From reliability point of view, to get optimum reliability in power generation, it is desirable to select a wind turbine generator which is best suited for a site. The mathematical relationship developed in this paper can be used for site-matching turbine selection in reliability point of view.

  8. Compensatory Reserve Index: Performance of a Novel Monitoring Technology to Identify the Bleeding Trauma Patient.

    Johnson, Michael; Alarhayem, Abdul; Convertino, Victor; Carter, Robert; Chung, Kevin; Stewart, Ronald; Myers, John; Dent, Daniel; Liao, Lilian; Cestero, Ramon; Nicholson, Susannah; Muir, Mark; Schwacha, Martin; Wampler, David; DeRosa, Mark; Eastridge, Brian


    Hemorrhage is one of the most substantial causes of death after traumatic injury. Standard measures, including systolic blood pressure (SBP), are poor surrogate indicators of physiologic compromise until compensatory mechanisms have been overwhelmed. Compensatory Reserve Index (CRI) is a novel monitoring technology with the ability to assess physiologic reserve. We hypothesized CRI would be a better predictor of physiologic compromise secondary to hemorrhage than traditional vital signs. A prospective observational study of 89 subjects meeting trauma center activation criteria at a single level I trauma center was conducted from October 2015 to February 2016. Data collected included demographics, SBP, HR, and requirement for hemorrhage-associated, life-saving intervention (LSI) (ie: operation or angiography for hemorrhage, local or tourniquet control of external bleeding and transfusion > 2 u PRBC). Receiver-operator characteristic (ROC) curves were formulated and appropriate thresholds were calculated to compare relative value of the metrics for predictive modeling. For predicting hemorrhage-related LSI, CRI demonstrated a sensitivity of 83% and a negative predictive value (NPV) of 91% as compared to SBP with a sensitivity to detect hemorrhage of 26% (p requiring potentially life-saving therapy more reliably than SBP (p < 0.05). The CRI device demonstrated superior capacity over systolic blood pressure in predicting the need for posttraumatic hemorrhage intervention in the acute resuscitation phase after injury.

  9. Research of Reliable Power Supply Schemes for OOO Gazprom Production Yamburg Gas Field

    Askarov Alisher


    Full Text Available In article the analysis of substation electric part for the enterprises an oil and gas complex power supply is carried out: structure and switchgear schemes, uninterrupted reserve sources structure. Recommendations for power supply reliability are made.

  10. 78 FR 44909 - Regional Reliability Standard BAL-002-WECC-2-Contingency Reserve


    ... language to clarify this point.\\19\\ \\18\\ Id. P 43. \\19\\ Id. PP 48-49. 4. Demand-Side Management as a... allow demand-side management that is technically capable of providing this service to be used as a... explicitly provide that demand-side management technically capable of providing this service may be used as...

  11. Reliability Modeling and Analysis of SCI Topological Network

    Hongzhe Xu


    Full Text Available The problem of reliability modeling on the Scalable Coherent Interface (SCI rings and topological network is studied. The reliability models of three SCI rings are developed and the factors which influence the reliability of SCI rings are studied. By calculating the shortest path matrix and the path quantity matrix of different types SCI network topology, the communication characteristics of SCI network are obtained. For the situations of the node-damage and edge-damage, the survivability of SCI topological network is studied.

  12. Reliability estimates for flawed mortar projectile bodies

    Cordes, J.A. [US Army ARDEC, AMSRD-AAR-MEF-E, Analysis and Evaluation Division, Fuze and Precision Armaments Technology Directorate, US Army Armament Research Development and Engineering Center, Picatinny Arsenal, NJ 07806-5000 (United States)], E-mail:; Thomas, J.; Wong, R.S.; Carlucci, D. [US Army ARDEC, AMSRD-AAR-MEF-E, Analysis and Evaluation Division, Fuze and Precision Armaments Technology Directorate, US Army Armament Research Development and Engineering Center, Picatinny Arsenal, NJ 07806-5000 (United States)


    The Army routinely screens mortar projectiles for defects in safety-critical parts. In 2003, several lots of mortar projectiles had a relatively high defect rate, 0.24%. Before releasing the projectiles, the Army reevaluated the chance of a safety-critical failure. Limit state functions and Monte Carlo simulations were used to estimate reliability. Measured distributions of wall thickness, defect rate, material strength, and applied loads were used with calculated stresses to estimate the probability of failure. The results predicted less than one failure in one million firings. As of 2008, the mortar projectiles have been used without any safety-critical incident.

  13. Higher Power Supply Reliability of Agro-Industrial Complex (AIC Consumers

    V. I. Rusan


    Full Text Available The paper presents the developed methodology that has been used for making calculations of main reliability indices for existing electric power supply circuits of AIC consumers. Some measures pertaining to provision of higher reliability are given in the paper. The paper contains calculations of changes in respect of reliability indices and reduction in cost of supply lost due to power supply interruptions in case of introduction of the proposed  measures.

  14. Reliability engineering theory and practice

    Birolini, Alessandro


    Presenting a solid overview of reliability engineering, this volume enables readers to build and evaluate the reliability of various components, equipment and systems. Current applications are presented, and the text itself is based on the author's 30 years of experience in the field.

  15. The Validity of Reliability Measures.

    Seddon, G. M.


    Demonstrates that some commonly used indices can be misleading in their quantification of reliability. The effects are most pronounced on gain or difference scores. Proposals are made to avoid sources of invalidity by using a procedure to assess reliability in terms of upper and lower limits for the true scores of each examinee. (Author/JDH)

  16. Software Reliability through Theorem Proving

    S.G.K. Murthy


    Full Text Available Improving software reliability of mission-critical systems is widely recognised as one of the major challenges. Early detection of errors in software requirements, designs and implementation, need rigorous verification and validation techniques. Several techniques comprising static and dynamic testing approaches are used to improve reliability of mission critical software; however it is hard to balance development time and budget with software reliability. Particularly using dynamic testing techniques, it is hard to ensure software reliability, as exhaustive testing is not possible. On the other hand, formal verification techniques utilise mathematical logic to prove correctness of the software based on given specifications, which in turn improves the reliability of the software. Theorem proving is a powerful formal verification technique that enhances the software reliability for missioncritical aerospace applications. This paper discusses the issues related to software reliability and theorem proving used to enhance software reliability through formal verification technique, based on the experiences with STeP tool, using the conventional and internationally accepted methodologies, models, theorem proving techniques available in the tool without proposing a new model.Defence Science Journal, 2009, 59(3, pp.314-317, DOI:

  17. Reliability engineering in RF CMOS


    In this thesis new developments are presented for reliability engineering in RF CMOS. Given the increase in use of CMOS technology in applications for mobile communication, also the reliability of CMOS for such applications becomes increasingly important. When applied in these applications, CMOS is typically referred to as RF CMOS, where RF stands for radio frequencies.

  18. Reliability in automotive ethernet networks

    Soares, Fabio L.; Campelo, Divanilson R.; Yan, Ying;


    This paper provides an overview of in-vehicle communication networks and addresses the challenges of providing reliability in automotive Ethernet in particular.......This paper provides an overview of in-vehicle communication networks and addresses the challenges of providing reliability in automotive Ethernet in particular....

  19. Estimation of Bridge Reliability Distributions

    Thoft-Christensen, Palle

    In this paper it is shown how the so-called reliability distributions can be estimated using crude Monte Carlo simulation. The main purpose is to demonstrate the methodology. Therefor very exact data concerning reliability and deterioration are not needed. However, it is intended in the paper to ...

  20. Reliability of the hip examination in osteoarthritis: effect of standardization.

    Cibere, Jolanda; Thorne, Anona; Bellamy, Nicholas; Greidanus, Nelson; Chalmers, Andrew; Mahomed, Nizar; Shojania, Kam; Kopec, Jacek; Esdaile, John M


    To assess the reliability of the physical examination of the hip in osteoarthritis (OA) among rheumatologists and orthopedic surgeons, and to evaluate the benefits of standardization. Thirty-five physical signs and techniques were evaluated using a 6 x 6 Latin square design. Subjects with mild to severe hip OA, based on physical and radiographic signs, were examined in random order prior to and following standardization of physical examination techniques. For dichotomous signs, agreement was calculated as the prevalence-adjusted bias-adjusted kappa (PABAK), whereas for continuous and ordinal signs a reliability coefficient was calculated using analysis of variance. A PABAK >0.60 and a reliability coefficient >0.80 were considered to indicate adequate reliability. Adequate post-standardization reliability was achieved for 25 (71%) of 35 signs. The most highly reliable signs included true and apparent leg length discrepancy > or =1.5 cm; hip flexion, abduction, adduction, and extension strength; log roll test for hip pain; internal rotation and flexion range of motion; and Thomas test for flexion contracture. The standardization process was associated with substantial improvements in reliability for a number of physical signs, although minimal or no change was noted for some. Only 1 sign, Trendelenburg's sign, was highly unreliable post-standardization. With the exception of gait, a comprehensive hip examination can be performed with adequate reliability. Post-standardization reliability is improved compared with pre-standardization reliability for some physical signs. The application of these findings to future OA studies will contribute to improved outcome assessments in OA.

  1. Alternative Approaches for Incentivizing the Frequency Responsive Reserve Ancillary Service

    Ela, E.; Milligan, M.; Kirby, B.; Tuohy, A.; Brooks, D.


    Frequency responsive reserve is the autonomous response of generators and demand response to deviations of system frequency, usually as a result of the instantaneous outage of a large supplier. Frequency responsive reserve arrests the frequency decline resulting in the stabilization of system frequency, and avoids the triggering of under-frequency load-shedding or the reaching of unstable frequencies that could ultimately lead to system blackouts. It is a crucial service required to maintain a reliable and secure power system. Regions with restructured electricity markets have historically had a lack of incentives for frequency responsive reserve because generators inherently provided the response and on large interconnected systems, more than sufficient response has been available. This may not be the case in future systems due to new technologies and declining response. This paper discusses the issues that can occur without proper incentives and even disincentives, and proposes alternatives to introduce incentives for resources to provide frequency responsive reserve to ensure an efficient and reliable power system.


    B.Anni Princy


    Full Text Available A software reliability exemplary projects snags the random process as disillusionments which were the culmination yield of two progressions: emerging faults and initial state values. The predominant classification uses the logistic analysis effort function mounting efficient software on the real time dataset. The detriments of the logistic testing were efficaciously overcome by Pareto distribution. The estimated outline ventures the resolved technique for analyzing the suitable communities and the preeminent of fit for a software reliability progress model. Its constraints are predictable to evaluate the reliability of a software system. The future process will permit for software reliability estimations that can be used both as prominence Indicator, but also for planning and controlling resources, the development times based on the onslaught assignments of the efficient computing and reliable measurement of a software system was competent.

  3. Reliability estimation using kriging metamodel

    Cho, Tae Min; Ju, Byeong Hyeon; Lee, Byung Chai [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Jung, Do Hyun [Korea Automotive Technology Institute, Chonan (Korea, Republic of)


    In this study, the new method for reliability estimation is proposed using kriging metamodel. Kriging metamodel can be determined by appropriate sampling range and sampling numbers because there are no random errors in the Design and Analysis of Computer Experiments(DACE) model. The first kriging metamodel is made based on widely ranged sampling points. The Advanced First Order Reliability Method(AFORM) is applied to the first kriging metamodel to estimate the reliability approximately. Then, the second kriging metamodel is constructed using additional sampling points with updated sampling range. The Monte-Carlo Simulation(MCS) is applied to the second kriging metamodel to evaluate the reliability. The proposed method is applied to numerical examples and the results are almost equal to the reference reliability.

  4. Reliability-Based Code Calibration

    Faber, M.H.; Sørensen, John Dalsgaard


    The present paper addresses fundamental concepts of reliability based code calibration. First basic principles of structural reliability theory are introduced and it is shown how the results of FORM based reliability analysis may be related to partial safety factors and characteristic values....... Thereafter the code calibration problem is presented in its principal decision theoretical form and it is discussed how acceptable levels of failure probability (or target reliabilities) may be established. Furthermore suggested values for acceptable annual failure probabilities are given for ultimate...... and serviceability limit states. Finally the paper describes the Joint Committee on Structural Safety (JCSS) recommended procedure - CodeCal - for the practical implementation of reliability based code calibration of LRFD based design codes....

  5. Photovoltaic performance and reliability workshop

    Mrig, L. [ed.


    This workshop was the sixth in a series of workshops sponsored by NREL/DOE under the general subject of photovoltaic testing and reliability during the period 1986--1993. PV performance and PV reliability are at least as important as PV cost, if not more. In the US, PV manufacturers, DOE laboratories, electric utilities, and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in the field were brought together to exchange the technical knowledge and field experience as related to current information in this evolving field of PV reliability. The papers presented here reflect this effort since the last workshop held in September, 1992. The topics covered include: cell and module characterization, module and system testing, durability and reliability, system field experience, and standards and codes.

  6. Reliability analysis of retaining walls with multiple failure modes

    张道兵; 孙志彬; 朱川曲


    In order to reduce the errors of the reliability of the retaining wall structure in the establishment of function, in the estimation of parameter and algorithm, firstly, two new reliability and stability models of anti-slipping and anti-overturning based on the upper-bound theory of limit analysis were established, and two kinds of failure modes were regarded as a series of systems with multiple correlated failure modes. Then, statistical characteristics of parameters of the retaining wall structure were inferred by maximal entropy principle. At last, the structural reliabilities of single failure mode and multiple failure modes were calculated by Monte Carlo method in MATLAB and the results were compared and analyzed on the sensitivity. It indicates that this method, with a high precision, is not only easy to program and quick in calculation, but also without the limit of nonlinear functions and non-normal random variables. And the results calculated by this method which applies both the limit analysis theory, maximal entropy principle and Monte Carlo method into analyzing the reliability of the retaining wall structures is more scientific, accurate and reliable, in comparison with those calculated by traditional method.

  7. Influence of the experience of the reader on reliability of joint space width measurement. A cross-sectional multiple reading study in hip osteoarthritis.

    Ornetti, Paul; Maillefert, Jean-Francis; Paternotte, Simon; Dougados, Maxime; Gossec, Laure


    The objectives were to evaluate improvement in reliability of joint space width (JSW) measurements, according to the previous experience of the readers in hip osteoarthritis (OA). Fifty radiographs in hip OA patients from a randomized controlled trial (ECHODIAH) were read 12 times by two readers with different levels of experience in radiographic interpretation. Intra-reader reliability and inter-reader reliability were assessed through calculation of the smallest detectable difference (SDD) and the intra-class correlation coefficient (ICC). Intra-reader reliability: for the experienced reader, no significant change in SDD was observed with repeated JSW measurements. For the junior reader, the SDD decreased significantly from 0.90 mm to 0.65 mm (P=0.002). A plateau of SDD was reached after reading 200 to 300 radiographs, with a value close to the mean SDD of the experienced reader (0.67 mm). ICCs were high (>0.88) for both the senior and the junior readers. Inter-reader reliability: no improvement in inter-reader reliability was noted with repeated measurements of JSW (SDD=0.81 mm). However, no additional training sessions were performed. ICCs were high (>0.85). This study indicated for the first time a learning curve in analyzing JSW in hip OA for an inexperienced reader. After analyzing 200 to 300 radiographs, the junior reader reached an intra-reader reliability similar to the experienced reader. Moreover, the information brought by the ICC was not sufficient, suggesting that the SDD should be systematically reported in studies evaluating OA radiographic progression, on top of the ICC, to help in interpreting the JSW reliability. Copyright © 2010 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

  8. Genetic optimization of reliability design of machine element

    郭观七; 喻寿益


    Canonical genetic algorithms have the defects of prematurity and stagnation when applied in optimization problems. The causes resulting in such phenomena were analyzed and a class of improved genetic algorithm with niche implemented by crossover of similar individuals and (μ+λ) selection was proposed. According to the reliability design theory of machine components, the genetic optimization model of jack clutch was obtained. An optimization instance and some results calculated by improved genetic algorithm were presented. The results of emulations and application show that the improved genetic algorithm with the niche technique can achieve the reliable global convergence and stable convergent velocity almost without any additional calculation expense.

  9. Reliability of stiffened structural panels: Two examples

    Stroud, W. Jefferson; Davis, D. Dale, Jr.; Maring, Lise D.; Krishnamurthy, Thiagaraja; Elishakoff, Isaac


    The reliability of two graphite-epoxy stiffened panels that contain uncertainties is examined. For one panel, the effect of an overall bow-type initial imperfection is studied. The size of the bow is assumed to be a random variable. The failure mode is buckling. The benefits of quality control are explored by using truncated distributions. For the other panel, the effect of uncertainties in a strain-based failure criterion is studied. The allowable strains are assumed to be random variables. A geometrically nonlinear analysis is used to calculate a detailed strain distribution near an elliptical access hole in a wing panel that was tested to failure. Calculated strains are used to predict failure. Results are compared with the experimental failure load of the panel.

  10. Discounting medical malpractice claim reserves for self-insured hospitals.

    Frese, Richard; Kitchen, Patrick


    The hospital CFO often works with the hospital's actuary and external auditor to calculate the reserves recorded in financial statements. Hospital management, usually the CFO, needs to decide the discount rate that is most appropriate. A formal policy addressing the rationale for discounting and the rationale for selecting the discount rate can be helpful to the CFO, actuary, and external auditor.

  11. Operational reliability evaluation of restructured power systems with wind power penetration utilizing reliability network equivalent and time-sequential simulation approaches

    Ding, Yi; Cheng, Lin; Zhang, Yonghong


    and reserve provides, fast reserve providers and transmission network in restructured power systems. A contingency management schema for real time operation considering its coupling with the day-ahead market is proposed. The time-sequential Monte Carlo simulation is used to model the chronological...... with high wind power penetration. The proposed technique is based on the combination of the reliability network equivalent and time-sequential simulation approaches. The operational reliability network equivalents are developed to represent reliability models of wind farms, conventional generation...... characteristics of corresponding reliability network equivalents. A simplified method is also developed in the simulation procedures for improving the computational efficiency. The proposed technique can be used to evaluate customers’ reliabilities considering high penetration of wind power during the power...

  12. 42 CFR 403.254 - Calculation of premiums.


    ... Ratio Provisions § 403.254 Calculation of premiums. (a) General provisions. To calculate the amount of... loss ratio calculation period. (b) Specific provisions. (1) Earned premium for a given period means— (i) Written premiums for the period; plus— (ii) The total premium reserve at the beginning of the period;...

  13. Neurotransplantation therapy and cerebellar reserve.

    Cendelin, Jan; Mitoma, Hiroshi; Manto, Mario


    Neurotransplantation has been recently the focus of interest as a promising therapy to substitute lost cerebellar neurons and improve cerebellar ataxias. However, since cell differentiation and synaptic formation are required to obtain a functional circuitry, highly integrated reproduction of cerebellar anatomy is not a simple process. Rather than a genuine replacement, recent studies have shown that grafted cells rescue surviving cells from neurodegeneration by exerting trophic effects, supporting mitochondrial function, modulating neuroinflammation, stimulating endogenous regenerative processes, and facilitating cerebellar compensatory properties thanks to neural plasticity. On the other hand, accumulating clinical evidence suggests that the self-recovery capacity is still preserved even if the cerebellum is affected by a diffuse and progressive pathology. We put forward the period with intact recovery capacity as "restorable stage" and the notion of reversal capacity as "cerebellar reserve". The concept of cerebellar reserve is particularly relevant, both theoretically and practically, to target recovery of cerebellar deficits by neurotransplantation. Reinforcing the cerebellar reserve and prolonging the restorable stage can be envisioned as future endpoints of neurotransplantation. Copyright© Bentham Science Publishers; For any queries, please email at

  14. Traumatic brain injury and reserve.

    Bigler, Erin D; Stern, Yaakov


    The potential role of brain and cognitive reserve in traumatic brain injury (TBI) is reviewed. Brain reserve capacity (BRC) refers to preinjury quantitative measures such as brain size that relate to outcome. Higher BRC implies threshold differences when clinical deficits will become apparent after injury, where those individuals with higher BRC require more pathology to reach that threshold. Cognitive reserve (CR) refers to how flexibly and efficiently the individual makes use of available brain resources. The CR model suggests the brain actively attempts to cope with brain damage by using pre-existing cognitive processing approaches or by enlisting compensatory approaches. Standard proxies for CR include education and IQ although this has expanded to include literacy, occupational attainment, engagement in leisure activities, and the integrity of social networks. Most research on BRC and CR has taken place in aging and degenerative disease but these concepts likely apply to the effects of TBI, especially with regards to recovery. Since high rates of TBI occur in those under age 35, both CR and BRC factors likely relate to how the individual copes with TBI over the lifespan. These factors may be particularly relevant to the relationship of developing dementia in the individual who has sustained a TBI earlier in life.

  15. Flexible Mental Calculation.

    Threlfall, John


    Suggests that strategy choice is a misleading characterization of efficient mental calculation and that teaching mental calculation methods as a whole is not conducive to flexibility. Proposes an alternative in which calculation is thought of as an interaction between noticing and knowledge. Presents an associated teaching approach to promote…

  16. Geochemical Calculations Using Spreadsheets.

    Dutch, Steven Ian


    Spreadsheets are well suited to many geochemical calculations, especially those that are highly repetitive. Some of the kinds of problems that can be conveniently solved with spreadsheets include elemental abundance calculations, equilibrium abundances in nuclear decay chains, and isochron calculations. (Author/PR)

  17. Autistic Savant Calendar Calculators.

    Patti, Paul J.

    This study identified 10 savants with developmental disabilities and an exceptional ability to calculate calendar dates. These "calendar calculators" were asked to demonstrate their abilities, and their strategies were analyzed. The study found that the ability to calculate dates into the past or future varied widely among these…

  18. Utilizing reliable and clinically significant change criteria to assess for the development of depression during smoking cessation treatment: the importance of tracking idiographic change.

    Busch, Andrew M; Wagener, Theodore L; Gregor, Kristin L; Ring, Kevin T; Borrelli, Belinda


    Studies typically measure mood changes during smoking cessation treatment in two ways: (a) by tracking mean change in depression scores or (b) by tracking the incidence of major depression development using diagnostic assessments. However, tracking mean change does not capture variability in individual mood trajectories, and diagnosing participants at multiple time points is time and labor intensive. The current study proposes a method of assessing meaningful increases in depression without the use of diagnostic assessments by utilizing reliable and clinically significant change criteria. This method was applied to 212 participants in a smoking cessation trial to explore the relationship between smoking status and depressed mood, assessed at baseline, end-of-treatment, and 2-, 6-, and 12-month follow-ups. High rates of reliable (24-28%) and both reliable and clinically significant increases (23-24%) in depressed mood were observed across all participants, regardless of whether or not they achieved abstinence. However, when we calculated group mean change in depression during the trial, only decreases in depressed mood where observed across several intervals. Findings indicate that utilizing reliable and clinically significant change criteria to track symptoms of depression during smoking cessation treatment leads to different conclusions than simply tracking mean changes. We propose that a combination of reliable and clinically significant change criteria may serve as a useful proxy measure for the development of major depressive disorder during smoking cessation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. The reliability of a modified Kalamazoo Consensus Statement Checklist for assessing the communication skills of multidisciplinary clinicians in the simulated environment.

    Peterson, Eleanor B; Calhoun, Aaron W; Rider, Elizabeth A


    With increased recognition of the importance of sound communication skills and communication skills education, reliable assessment tools are essential. This study reports on the psychometric properties of an assessment tool based on the Kalamazoo Consensus Statement Essential Elements Communication Checklist. The Gap-Kalamazoo Communication Skills Assessment Form (GKCSAF), a modified version of an existing communication skills assessment tool, the Kalamazoo Essential Elements Communication Checklist-Adapted, was used to assess learners in a multidisciplinary, simulation-based communication skills educational program using multiple raters. 118 simulated conversations were available for analysis. Internal consistency and inter-rater reliability were determined by calculating a Cronbach's alpha score and intra-class correlation coefficients (ICC), respectively. The GKCSAF demonstrated high internal consistency with a Cronbach's alpha score of 0.844 (faculty raters) and 0.880 (peer observer raters), and high inter-rater reliability with an ICC of 0.830 (faculty raters) and 0.89 (peer observer raters). The Gap-Kalamazoo Communication Skills Assessment Form is a reliable method of assessing the communication skills of multidisciplinary learners using multi-rater methods within the learning environment. The Gap-Kalamazoo Communication Skills Assessment Form can be used by educational programs that wish to implement a reliable assessment and feedback system for a variety of learners. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. Modelling and Simulation of Scraper Reliability for Maintenance

    HUANG Liang-pei; LU Zhong-hai; GONG Zheng-li


    A scraper conveyor is a kind of heavy machinery which can continuously transport goods and widely used in mines, ports and store enterprises. Since scraper failure rate directly affects production costs and production capacity, the evaluation and the prediction of scraper conveyor reliability are important for these enterprises. In this paper, the reliabilities of different parts are classified and discussed according to their structural characteristics and different failure factors. Based on the component's time-to-failure density function, the reliability model of scraper chain is constructed to track the age distribution of part population and the reliability change of the scraper chain. Based on the stress-strength interference model, considering the decrease of strength due to fatigue failure, the dynamic reliability model of such component as gear, axis is developed to observe the change of the part reliability with the service time of scraper. Finally, system reliability model of the scraper is established for the maintenance to simulate and calculate the scraper reliability.

  1. Examining the reliability of ADAS-Cog change scores.

    Grochowalski, Joseph H; Liu, Ying; Siedlecki, Karen L


    The purpose of this study was to estimate and examine ways to improve the reliability of change scores on the Alzheimer's Disease Assessment Scale, Cognitive Subtest (ADAS-Cog). The sample, provided by the Alzheimer's Disease Neuroimaging Initiative, included individuals with Alzheimer's disease (AD) (n = 153) and individuals with mild cognitive impairment (MCI) (n = 352). All participants were administered the ADAS-Cog at baseline and 1 year, and change scores were calculated as the difference in scores over the 1-year period. Three types of change score reliabilities were estimated using multivariate generalizability. Two methods to increase change score reliability were evaluated: reweighting the subtests of the scale and adding more subtests. Reliability of ADAS-Cog change scores over 1 year was low for both the AD sample (ranging from .53 to .64) and the MCI sample (.39 to .61). Reweighting the change scores from the AD sample improved reliability (.68 to .76), but lengthening provided no useful improvement for either sample. The MCI change scores had low reliability, even with reweighting and adding additional subtests. The ADAS-Cog scores had low reliability for measuring change. Researchers using the ADAS-Cog should estimate and report reliability for their use of the change scores. The ADAS-Cog change scores are not recommended for assessment of meaningful clinical change.

  2. Reliability models applicable to space telescope solar array assembly system

    Patil, S. A.


    A complex system may consist of a number of subsystems with several components in series, parallel, or combination of both series and parallel. In order to predict how well the system will perform, it is necessary to know the reliabilities of the subsystems and the reliability of the whole system. The objective of the present study is to develop mathematical models of the reliability which are applicable to complex systems. The models are determined by assuming k failures out of n components in a subsystem. By taking k = 1 and k = n, these models reduce to parallel and series models; hence, the models can be specialized to parallel, series combination systems. The models are developed by assuming the failure rates of the components as functions of time and as such, can be applied to processes with or without aging effects. The reliability models are further specialized to Space Telescope Solar Arrray (STSA) System. The STSA consists of 20 identical solar panel assemblies (SPA's). The reliabilities of the SPA's are determined by the reliabilities of solar cell strings, interconnects, and diodes. The estimates of the reliability of the system for one to five years are calculated by using the reliability estimates of solar cells and interconnects given n ESA documents. Aging effects in relation to breaks in interconnects are discussed.

  3. Spinning Reserve Requirements Optimization Based on an Improved Multiscenario Risk Analysis Method

    Liudong Zhang


    Full Text Available This paper proposes a novel security-constrained unit commitment model to calculate the optimal spinning reserve (SR amount. The model combines cost-benefit analysis with an improved multiscenario risk analysis method capable of considering various uncertainties, including load and wind power forecast errors as well as forced outages of generators. In this model, cost-benefit analysis is utilized to simultaneously minimize the operation cost of conventional generators, the expected cost of load shedding, the penalty cost of wind power spillage, and the carbon emission cost. It remedies the defects of the deterministic and probabilistic methods of SR calculation. In cases where load and wind power generation are negatively correlated, this model based on multistep modeling of net demand can consider the wind power curtailment to maximize the overall economic efficiency of system operation so that the optimal economic values of wind power and SR are achieved. In addition, the impact of the nonnormal probability distributions of wind power forecast error on SR optimization can be taken into account. Using mixed integer linear programming method, simulation studies on a modified IEEE 26-generator reliability test system connected to a wind farm are performed to confirm the effectiveness and advantage of the proposed model.

  4. How Do Calculators Calculate Trigonometric Functions?

    Underwood, Jeremy M.; Edwards, Bruce H.

    How does your calculator quickly produce values of trigonometric functions? You might be surprised to learn that it does not use series or polynomial approximations, but rather the so-called CORDIC method. This paper will focus on the geometry of the CORDIC method, as originally developed by Volder in 1959. This algorithm is a wonderful…

  5. Electronic parts reliability data 1997

    Denson, William; Jaworski, Paul; Mahar, David


    This document contains reliability data on both commercial and military electronic components for use in reliability analyses. It contains failure rate data on integrated circuits, discrete semiconductors (diodes, transistors, optoelectronic devices), resistors, capacitors, and inductors/transformers, all of which were obtained from the field usage of electronic components. At 2,000 pages, the format of this document is the same as RIAC's popular NPRD document which contains reliability data on nonelectronic component and electronic assembly types. Data includes part descriptions, quality level, application environments, point estimates of failure rate, data sources, number of failures, total operating hours, miles, or cycles, and detailed part characteristics.

  6. Optimal Reserve Management Pattern for Turkish Banks

    Anil Talasli; Suheyla Ozyildirim


    In this paper we model a representative bank’s optimal reserve management pattern by adopting institutional aspects of the Turkish required reserve regime. The cost minimization problem, in general, takes into account the expected opportunity cost of holding reserves and penalty costs for not fulfilling the liability of reserve requirement. We extend this problem for reserve carry-over provision and use of late liquidity window facility and compute the optimal reserve pattern by dynamic progr...

  7. Reserve a seat! Intelligent transportation reservation system for tourists

    Truett, L.F.; Tonn, B. [Oak Ridge National Lab., TN (United States); Conley, T. [GTE Wireless, Nashville, TN (United States)


    Providing safe, predictable, and efficient transportation for tourists to and from various venues presents a major challenge. Special-event transportation is notoriously unreliable and usually congested at peak times. The rural nature of certain tourist locations (e.g., the Grand Canyon) further complicates the problem. The proposed Intelligent Transportation Reservation System will have three components, each of which performs different functions. On-vehicle component: this component has three purposes: (1) to keep a running count of the passengers on the bus in order to determine how many additional passengers can be accommodated based on the total capacity of the vehicle; (2) through use of Global Positioning Satellite (GPS) technology, to be able to determine the location of the bus at all times; (3) to transmit information to a central data facility. Together these three features provide location, available-space, and condition information to controllers at a central data facility and to prospective riders of the bus. Kiosk component: located at every loading/unloading point, the purpose is to allow passengers-to-be to determine when the next bus (or buses) will arrive and the availability of seating. Individuals can make a reservation for the next bus with sufficient seating and will know when that bus will arrive at the kiosk. Information component: located within hotels and at venue sites, this component will provide information on the buses in the system (e.g. route and current capacity), and loading/unloading locations throughout the network at any point in time.

  8. Reserve a seat! Intelligent transportation reservation system for tourists

    Truett, L.F.; Tonn, B. [Oak Ridge National Lab., TN (United States); Conley, T. [GTE Wireless, Nashville, TN (United States)


    Providing safe, predictable, and efficient transportation for tourists to and from various venues presents a major challenge. Special-event transportation is notoriously unreliable and usually congested at peak times. The rural nature of certain tourist locations (e.g., the Grand Canyon) further complicates the problem. The proposed Intelligent Transportation Reservation System will have three components, each of which performs different functions. On-vehicle component: this component has three purposes: (1) to keep a running count of the passengers on the bus in order to determine how many additional passengers can be accommodated based on the total capacity of the vehicle; (2) through use of Global Positioning Satellite (GPS) technology, to be able to determine the location of the bus at all times; (3) to transmit information to a central data facility. Together these three features provide location, available-space, and condition information to controllers at a central data facility and to prospective riders of the bus. Kiosk component: located at every loading/unloading point, the purpose is to allow passengers-to-be to determine when the next bus (or buses) will arrive and the availability of seating. Individuals can make a reservation for the next bus with sufficient seating and will know when that bus will arrive at the kiosk. Information component: located within hotels and at venue sites, this component will provide information on the buses in the system (e.g. route and current capacity), and loading/unloading locations throughout the network at any point in time.

  9. Measures of cognitive reserve in Alzheimer's disease

    Margarida Sobral


    Full Text Available INTRODUCTION: Cognitive reserve (CR, a hypothetical construct used to obtain information about cognitive aging, describes the capacity of the adult brain to cope with the effects of neurodegenerative processes. This study evaluated CR using a CR questionnaire (CRQ and a set of variables (education, leisure activities, lifelong occupation that inform CR. It also developed a CR index, validated the CRQ, and examined the correlation between the different CR measures.METHODS: Functional and neuropsychological capacities of 75 outpatients (mean age: 80.2 years with a probable AD diagnosis were evaluated. Socio-demographic data and clinical variables were collected. Patients completed two questionnaires: the Participation in Leisure Activities throughout Life questionnaire, and the CRQ.RESULTS: Participants with a greater CR had higher scores in cognitive tests than the elderly with a lower CR. A CR index was developed. CRQ reliability was 0.795 (Cronbach's alpha. There was a close association between the CR Index and the CRQ.CONCLUSIONS: This study found an association between CR measures and education, occupation and participation in leisure activities. The CRQ seems to be a suitable instrument to measure CR in Portuguese populations.

  10. Target Heart Rate Calculator

    ... to the left or right of your Adam's apple. Or try the pulse spot inside your wrist ... fundraising notices Site Comments © 2017 American Cancer Society, Inc. All rights reserved. The American Cancer Society is ...

  11. Reliability Modeling of Wind Turbines

    Kostandyan, Erik

    and uncertainties are quantified. Further, estimation of annual failure probability for structural components taking into account possible faults in electrical or mechanical systems is considered. For a representative structural failure mode, a probabilistic model is developed that incorporates grid loss failures...... components. Thus, models of reliability should be developed and applied in order to quantify the residual life of the components. Damage models based on physics of failure combined with stochastic models describing the uncertain parameters are imperative for development of cost-optimal decision tools...... for Operation & Maintenance planning. Concentrating efforts on development of such models, this research is focused on reliability modeling of Wind Turbine critical subsystems (especially the power converter system). For reliability assessment of these components, structural reliability methods are applied...

  12. Reliability analysis in intelligent machines

    Mcinroy, John E.; Saridis, George N.


    Given an explicit task to be executed, an intelligent machine must be able to find the probability of success, or reliability, of alternative control and sensing strategies. By using concepts for information theory and reliability theory, new techniques for finding the reliability corresponding to alternative subsets of control and sensing strategies are proposed such that a desired set of specifications can be satisfied. The analysis is straightforward, provided that a set of Gaussian random state variables is available. An example problem illustrates the technique, and general reliability results are presented for visual servoing with a computed torque-control algorithm. Moreover, the example illustrates the principle of increasing precision with decreasing intelligence at the execution level of an intelligent machine.

  13. Reliability Assessment of Wind Turbines

    Sørensen, John Dalsgaard


    (and safe). In probabilistic design the single components are designed to a level of reliability, which accounts for an optimal balance between failure consequences, cost of operation & maintenance, material costs and the probability of failure. Furthermore, using a probabilistic design basis...... but manufactured in series production based on many component tests, some prototype tests and zeroseries wind turbines. These characteristics influence the reliability assessment where focus in this paper is on the structural components. Levelized Cost Of Energy is very important for wind energy, especially when...... comparing to other energy sources. Therefore much focus is on cost reductions and improved reliability both for offshore and onshore wind turbines. The wind turbine components should be designed to have sufficient reliability level with respect to both extreme and fatigue loads but also not be too costly...

  14. On Bayesian System Reliability Analysis

    Soerensen Ringi, M.


    The view taken in this thesis is that reliability, the probability that a system will perform a required function for a stated period of time, depends on a person`s state of knowledge. Reliability changes as this state of knowledge changes, i.e. when new relevant information becomes available. Most existing models for system reliability prediction are developed in a classical framework of probability theory and they overlook some information that is always present. Probability is just an analytical tool to handle uncertainty, based on judgement and subjective opinions. It is argued that the Bayesian approach gives a much more comprehensive understanding of the foundations of probability than the so called frequentistic school. A new model for system reliability prediction is given in two papers. The model encloses the fact that component failures are dependent because of a shared operational environment. The suggested model also naturally permits learning from failure data of similar components in non identical environments. 85 refs.

  15. VCSEL reliability: a user's perspective

    McElfresh, David K.; Lopez, Leoncio D.; Melanson, Robert; Vacar, Dan


    VCSEL arrays are being considered for use in interconnect applications that require high speed, high bandwidth, high density, and high reliability. In order to better understand the reliability of VCSEL arrays, we initiated an internal project at SUN Microsystems, Inc. In this paper, we present preliminary results of an ongoing accelerated temperature-humidity-bias stress test on VCSEL arrays from several manufacturers. This test revealed no significant differences between the reliability of AlGaAs, oxide confined VCSEL arrays constructed with a trench oxide and mesa for isolation. This test did find that the reliability of arrays needs to be measured on arrays and not be estimated with the data from singulated VCSELs as is a common practice.

  16. Innovations in power systems reliability

    Santora, Albert H; Vaccaro, Alfredo


    Electrical grids are among the world's most reliable systems, yet they still face a host of issues, from aging infrastructure to questions of resource distribution. Here is a comprehensive and systematic approach to tackling these contemporary challenges.

  17. Reliability of photographic posture analysis of adolescents.

    Hazar, Zeynep; Karabicak, Gul Oznur; Tiftikci, Ugur


    [Purpose] Postural problems of adolescents needs to be evaluated accurately because they may lead to greater problems in the musculoskeletal system as they develop. Although photographic posture analysis has been frequently used, more simple and accessible methods are still needed. The purpose of this study was to investigate the inter- and intra-rater reliability of photographic posture analysis using MB-ruler software. [Subjects and Methods] Subjects were 30 adolescents (15 girls and 15 boys, mean age: 16.4±0.4 years, mean height 166.3±6.7 cm, mean weight 63.8±15.1 kg) and photographs of their habitual standing posture photographs were taken in the sagittal plane. For the evaluation of postural angles, reflective markers were placed on anatomical landmarks. For angular measurements, MB-ruler (Markus Bader- MB Software Solutions, triangular screen ruler) was used. Photographic evaluations were performed by two observers with a repetition after a week. Test-retest and inter-rater reliability evaluations were calculated using intra-class correlation coefficients (ICC). [Results] Inter-rater (ICC>0.972) and test-retest (ICC>0.774) reliability were found to be in the range of acceptable to excellent. [Conclusion] Reference angles for postural evaluation were found to be reliable and repeatable. The present method was found to be an easy and non-invasive method and it may be utilized by researchers who are in search of an alternative method for photographic postural assessments.

  18. Option to Operate a Reserve of Energy Resource

    Urate, Kengo; Sekozawa, Teruji

    In this paper, the value generated by releasing petroleum reserves at the time of a crude oil price spike is analyzed to show the utility of releasing petroleum reserves. Japan's petroleum reserve currently only releases oil for the purpose of coping with a crude oil supply disruption. However, at present no disruptions to the supply of crude oil are occurring. To determine the value of the petroleum reserve if reserves are released when crude oil price spikes occur, option theory based on financial engineering is used to quantitatively calculate the value of a release into a market with stochastically changing prices. In addition, by examining the value that would have been generated as a function of release price if petroleum reserves had been released at the time of the crude oil price spike of 2008, it is possible to demonstrate the utility of such a release. Furthermore, input-output analysis is used to measure the impact on petrochemical product industries and other industries affected by price increases when crude oil price spikes occur to determine the degree of the price mitigation effect of a petroleum reserve with a release function.

  19. Foreign Exchange Reserves: Bangladesh Perspective

    Md Zahangir Alam


    Full Text Available This study is about foreign exchangereserves of Bangladesh. The mainpurpose of this study is to the influence of exchange rates on foreign exchangereserves to the Bangladesh context.  Both the primary and secondary data has been used inthis study. The primary data has been collected through a structuredquestionnaire from 50 respondents. The secondary data, namely Bangladeshforeign exchange reserves (FER, Bangladesh current account balance (CAB,Bangladesh capital andfinancial account balance (CFAB, and BDT/USD exchange rates (ER.  This study covers yearly data from July 01,1996 to June 30, 2005 and quarterly data from July 01, 2005 to June 30, 2012. Findingsof this study shows that out of the selected 16 factors affecting foreignexchange reserves, exchange rates occupy the first position, weighted averagescore (WAS being 4.56. Foreign exchange reserves (FER and current accountbalance (CAB have increased by 502.9087% and 1451.218%,whereas capital and financial account (CFAB has decreased by -649.024% on June30, 2012 compared to June 30, 1997. The influence of other factors heldconstant, as ER changes by 285.6894 units due to one unit change in FER, onaverage in the same direction which represents that ER has positive effect on theFER and this relationship is statistically significant.  62.1526 percentof the variation in FER is explained by ER. The outcomes of Breusch-Godfrey test (LM test, ARCHtest, and the Normality test are that there is a serial correlation among residuals, the variance of residuals is notconstant, and the residuals are not normally distributed.

  20. Accelerator Availability and Reliability Issues

    Steve Suhring


    Maintaining reliable machine operations for existing machines as well as planning for future machines' operability present significant challenges to those responsible for system performance and improvement. Changes to machine requirements and beam specifications often reduce overall machine availability in an effort to meet user needs. Accelerator reliability issues from around the world will be presented, followed by a discussion of the major factors influencing machine availability.

  1. Software Reliability Experimentation and Control

    Kai-Yuan Cai


    This paper classifies software researches as theoretical researches, experimental researches, and engineering researches, and is mainly concerned with the experimental researches with focus on software reliability experimentation and control. The state-of-the-art of experimental or empirical studies is reviewed. A new experimentation methodology is proposed, which is largely theory discovering oriented. Several unexpected results of experimental studies are presented to justify the importance of software reliability experimentation and control. Finally, a few topics that deserve future investigation are identified.

  2. Reliability of Foundation Pile Based on Settlement and a Parameter Sensitivity Analysis

    Shujun Zhang; Luo Zhong; Zhijun Xu


    Based on the uncertainty analysis to calculation model of settlement, the formula of reliability index of foundation pile is derived. Based on this formula, the influence of coefficient of variation of the calculated settlement at pile head, coefficient of variation of the permissible limit of the settlement, coefficient of variation of the measured settlement, safety coefficient, and the mean value of calculation model coefficient on reliability is analyzed. The results indicate that (1) hig...

  3. Deposit Reserve Rate No Panacea

    Mark; A.DeWeaver


    To rein in runaway investment, China's central bank, the People's Bank of China (PBOC), took several measures in mid-June, including the most dramatic step of raising the deposit reserve rate by 0.5 percentage point According to Mark A. DeWeaver, who manages Quantrarian Asia Hedge, a fund that invests in Asian equities, the PBOC's measures may lower money supply growth in the short term; that is, the effect of these measures "may be only temporary." He believes that "attempts to slow money supply growth ...

  4. Essays in the California electricity reserves markets

    Metaxoglou, Konstantinos

    This dissertation examines inefficiencies in the California electricity reserves markets. In Chapter 1, I use the information released during the investigation of the state's electricity crisis of 2000 and 2001 by the Federal Energy Regulatory Commission to diagnose allocative inefficiencies. Building upon the work of Wolak (2000), I calculate a lower bound for the sellers' price-cost margins using the inverse elasticities of their residual demand curves. The downward bias in my estimates stems from the fact that I don't account for the hierarchical substitutability of the reserve types. The margins averaged at least 20 percent for the two highest quality types of reserves, regulation and spinning, generating millions of dollars in transfers to a handful of sellers. I provide evidence that the deviations from marginal cost pricing were due to the markets' high concentration and a principal-agent relationship that emerged from their design. In Chapter 2, I document systematic differences between the markets' day- and hour-ahead prices. I use a high-dimensional vector moving average model to estimate the premia and conduct correct inferences. To obtain exact maximum likelihood estimates of the model, I employ the EM algorithm that I develop in Chapter 3. I uncover significant day-ahead premia, which I attribute to market design characteristics too. On the demand side, the market design established a principal-agent relationship between the markets' buyers (principal) and their supervisory authority (agent). The agent had very limited incentives to shift reserve purchases to the lower priced hour-ahead markets. On the supply side, the market design raised substantial entry barriers by precluding purely speculative trading and by introducing a complicated code of conduct that induced uncertainty about which actions were subject to regulatory scrutiny. In Chapter 3, I introduce a state-space representation for vector autoregressive moving average models that enables

  5. Notes on numerical reliability of several statistical analysis programs

    Landwehr, J.M.; Tasker, Gary D.


    This report presents a benchmark analysis of several statistical analysis programs currently in use in the USGS. The benchmark consists of a comparison between the values provided by a statistical analysis program for variables in the reference data set ANASTY and their known or calculated theoretical values. The ANASTY data set is an amendment of the Wilkinson NASTY data set that has been used in the statistical literature to assess the reliability (computational correctness) of calculated analytical results.

  6. Flexible reserve markets for wind integration

    Fernandez, Alisha R.

    The increased interconnection of variable generation has motivated the use of improved forecasting to more accurately predict future production with the purpose to lower total system costs for balancing when the expected output exceeds or falls short of the actual output. Forecasts are imperfect, and the forecast errors associated with utility-scale generation from variable generators need new balancing capabilities that cannot be handled by existing ancillary services. Our work focuses on strategies for integrating large amounts of wind generation under the flex reserve market, a market that would called upon for short-term energy services during an under or oversupply of wind generation to maintain electric grid reliability. The flex reserve market would be utilized for time intervals that fall in-between the current ancillary services markets that would be longer than second-to-second energy services for maintaining system frequency and shorter than reserve capacity services that are called upon for several minutes up to an hour during an unexpected contingency on the grid. In our work, the wind operator would access the flex reserve market as an energy service to correct for unanticipated forecast errors, akin to paying the generators participating in the market to increase generation during a shortfall or paying the other generators to decrease generation during an excess of wind generation. Such a market does not currently exist in the Mid-Atlantic United States. The Pennsylvania-New Jersey-Maryland Interconnection (PJM) is the Mid-Atlantic electric grid case study that was used to examine if a flex reserve market can be utilized for integrating large capacities of wind generation in a lowcost manner for those providing, purchasing and dispatching these short-term balancing services. The following work consists of three studies. The first examines the ability of a hydroelectric facility to provide short-term forecast error balancing services via a flex

  7. MEMS reliability: coming of age

    Douglass, Michael R.


    In today's high-volume semiconductor world, one could easily take reliability for granted. As the MOEMS/MEMS industry continues to establish itself as a viable alternative to conventional manufacturing in the macro world, reliability can be of high concern. Currently, there are several emerging market opportunities in which MOEMS/MEMS is gaining a foothold. Markets such as mobile media, consumer electronics, biomedical devices, and homeland security are all showing great interest in microfabricated products. At the same time, these markets are among the most demanding when it comes to reliability assurance. To be successful, each company developing a MOEMS/MEMS device must consider reliability on an equal footing with cost, performance and manufacturability. What can this maturing industry learn from the successful development of DLP technology, air bag accelerometers and inkjet printheads? This paper discusses some basic reliability principles which any MOEMS/MEMS device development must use. Examples from the commercially successful and highly reliable Digital Micromirror Device complement the discussion.

  8. Core calculations of JMTR

    Nagao, Yoshiharu [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment


    In material testing reactors like the JMTR (Japan Material Testing Reactor) of 50 MW in Japan Atomic Energy Research Institute, the neutron flux and neutron energy spectra of irradiated samples show complex distributions. It is necessary to assess the neutron flux and neutron energy spectra of an irradiation field by carrying out the nuclear calculation of the core for every operation cycle. In order to advance core calculation, in the JMTR, the application of MCNP to the assessment of core reactivity and neutron flux and spectra has been investigated. In this study, in order to reduce the time for calculation and variance, the comparison of the results of the calculations by the use of K code and fixed source and the use of Weight Window were investigated. As to the calculation method, the modeling of the total JMTR core, the conditions for calculation and the adopted variance reduction technique are explained. The results of calculation are shown. Significant difference was not observed in the results of neutron flux calculations according to the difference of the modeling of fuel region in the calculations by K code and fixed source. The method of assessing the results of neutron flux calculation is described. (K.I.)

  9. Inter-observer reliability of DSM-5 substance use disorders.

    Denis, Cécile M; Gelernter, Joel; Hart, Amy B; Kranzler, Henry R


    Although studies have examined the impact of changes made in DSM-5 on the estimated prevalence of substance use disorder (SUD) diagnoses, there is limited evidence concerning the reliability of DSM-5 SUDs. We evaluated the inter-observer reliability of four DSM-5 SUDs in a sample in which we had previously evaluated the reliability of DSM-IV diagnoses, allowing us to compare the two systems. Two different interviewers each assessed 173 subjects over a 2-week period using the Semi-Structured Assessment for Drug Dependence and Alcoholism (SSADDA). Using the percent agreement and kappa (κ) coefficient, we examined the reliability of DSM-5 lifetime alcohol, opioid, cocaine, and cannabis use disorders, which we compared to that of SSADDA-derived DSM-IV SUD diagnoses. We also assessed the effect of additional lifetime SUD and lifetime mood or anxiety disorder diagnoses on the reliability of the DSM-5 SUD diagnoses. Reliability was good to excellent for the four disorders, with κ values ranging from 0.65 to 0.94. Agreement was consistently lower for SUDs of mild severity than for moderate or severe disorders. DSM-5 SUD diagnoses showed greater reliability than DSM-IV diagnoses of abuse or dependence or dependence only. Co-occurring SUD and lifetime mood or anxiety disorders exerted a modest effect on the reliability of the DSM-5 SUD diagnoses. For alcohol, opioid, cocaine and cannabis use disorders, DSM-5 criteria and diagnoses are at least as reliable as those of DSM-IV. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. [Reliability of Primary Care computerised medication records].

    García-Molina Sáez, Celia; Urbieta Sanz, Elena; Madrigal de Torres, Manuel; Piñera Salmerón, Pascual; Pérez Cárceles, María D


    To quantify and to evaluate the reliability of Primary Care (PC) computerised medication records of as an information source of patient chronic medications, and to identify associated factors with the presence of discrepancies. A descriptive cross-sectional study. General Referral Hospital in Murcia. Patients admitted to the cardiology-chest diseases unit, during the months of February to April 2013, on home treatment, who agreed to participate in the study. Evaluation of the reliability of Primary Care computerised medication records by analysing the concordance, by identifying discrepancies, between the active medication in these records and that recorded in pharmacist interview with the patient/caregiver. Identification of associated factors with the presence of discrepancies was analysed using a multivariate logistic regression. The study included a total of 308 patients with a mean of 70.9 years (13.0 SD). The concordance of active ingredients was 83.7%, and this decreased to 34.7% when taking the dosage into account. Discrepancies were found in 97.1% of patients. The most frequent discrepancy was omission of frequency (35.6%), commission (drug added unjustifiably) (14.6%), and drug omission (12.7%). Age older than 65 years (1.98 [1.08 to 3.64]), multiple chronic diseases (1.89 [1.04 to 3.42]), and have a narcotic or psychotropic drug prescribed (2.22 [1.16 to 4.24]), were the factors associated with the presence of discrepancies. Primary Care computerised medication records, although of undoubted interest, are not be reliable enough to be used as the sole source of information on patient chronic medications when admitted to hospital. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

  11. Reliability and validity of the Spanish version of the modified Yale Preoperative Anxiety Scale.

    Jerez, C; Ullán, A M; Lázaro, J J


    To minimise preoperative stress and increase child cooperation during induction of anaesthesia is one of the most important perioperative objectives. The modified Yale Preoperative Anxiety Scale was developed to evaluate anxiety. The aim of this study was to translate into Spanish, and validate the psychometric properties of the Spanish version of this scale. The Spanish translation of the scale was performed following the World Health Organisation guidelines. During induction of anaesthesia, 81 children aged 2 to 12 years were recorded. Two observers evaluated the recordings independently. Content validity index of modified Yale Preoperative Anxiety Scale Spanish version was assessed. Weighted Kappa was calculated to measure interobserver agreement, and the Pearson correlation between the Induction Compliance Checklist and the modified Yale Preoperative Anxiety Scale was determined. The Spanish version obtained high content validity (0.91 to 0.98). Reliability analysis using weighted Kappa statistics revealed that interobserver agreement ranged from 0.54 to 0.75. Concurrent validity was high (r=0.94; P<.001). Validated assessment tools are needed to evaluate interventions to reduce child preoperative anxiety. The Spanish version of the modified Yale Preoperative Anxiety Scale evaluated in this study has shown good psychometric properties of reliability and validity. Copyright © 2015 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  12. System Reliability Assessment of Existing Jacket Platforms in Malaysian Waters

    V.J. Kurian


    Full Text Available Reliability of offshore platforms has become a very important issue in the Malaysian Oil and Gas Industry as, majority of the jacket platforms in Malaysian waters to date, have exceeded their design life. Reliability of a jacket platform can be assessed through reliability index and probability of failure. Conventional metocean consideration uses 100 year return period wave height associated with 100 year return period current velocity and wind speed. However, recent study shows that for Malaysian waters, the proposed metocean consideration should be 100 year return period wave height associated with 10 year return period current velocity and wind speed. Hence, this research investigated the effect of different metocean consideration, to system-based reliability of jacket platforms in Malaysian waters. Prior to that, the effect of different metocean consideration to the pushover analysis has also been studied. Besides, the significance of Pile Soil Interaction (PSI, wave direction and platform geometry were analyzed in a sensitivity study. Pushover analysis was performed on three jacket platforms representing three water regions in Malaysia to obtain Reserve Strength Ratio (RSR as an indicator of the reliability of the jackets. Utilizing sensitivity study parameters mentioned above, seven different case studies were undertaken to study their significance on RSR. The RSR values of each case study were compared and incorporated as resistance model of reliability analysis. Besides, platform specific response model of each jacket has been generated using response surface technique which was later incorporated into the limit state function for reliability analysis. Reliability analysis using First Order Reliability Method (FORM has been conducted in MATLAB to obtain the reliability index and probability of failure. Results from the reliability analysis were compared to analyze the effect of different metocean consideration. In this study, an updated

  13. Veterinary Science Students, Center Changing a Reservation

    Blackwater, Jasmine


    Kayenta is a rural community located in northeastern Arizona on a Navajo reservation. On the reservation, many families rely on their livestock for income, and as a result, many reservation high school students show a great interest in agricultural education. Having livestock on the reservation is not just a source of income, but also part of a…

  14. Calculating correct compilers

    Bahr, Patrick; Hutton, Graham


    In this article, we present a new approach to the problem of calculating compilers. In particular, we develop a simple but general technique that allows us to derive correct compilers from high-level semantics by systematic calculation, with all details of the implementation of the compilers...... falling naturally out of the calculation process. Our approach is based upon the use of standard equational reasoning techniques, and has been applied to calculate compilers for a wide range of language features and their combination, including arithmetic expressions, exceptions, state, various forms...

  15. Radar Signature Calculation Facility

    Federal Laboratory Consortium — FUNCTION: The calculation, analysis, and visualization of the spatially extended radar signatures of complex objects such as ships in a sea multipath environment and...

  16. Electrical installation calculations basic

    Kitcher, Christopher


    All the essential calculations required for basic electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practice. A step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3Fo

  17. Electrical installation calculations advanced

    Kitcher, Christopher


    All the essential calculations required for advanced electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practiceA step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3For apprentices and electrical installatio

  18. Electronics Environmental Benefits Calculator

    U.S. Environmental Protection Agency — The Electronics Environmental Benefits Calculator (EEBC) was developed to assist organizations in estimating the environmental benefits of greening their purchase,...

  19. Creation of Power Reserves Under the Market Economy Conditions

    Mahnitko, A.; Gerhards, J.; Lomane, T.; Ribakov, S.


    The main task of the control over an electric power system (EPS) is to ensure reliable power supply at the least cost. In this case, requirements to the electric power quality, power supply reliability and cost limitations on the energy resources must be observed. The available power reserve in an EPS is the necessary condition to keep it in operation with maintenance of normal operating variables (frequency, node voltage, power flows via the transmission lines, etc.). The authors examine possibilities to create power reserves that could be offered for sale by the electric power producer. They consider a procedure of price formation for the power reserves and propose a relevant mathematical model for a united EPS, the initial data being the fuel-cost functions for individual systems, technological limitations on the active power generation and consumers' load. As the criterion of optimization the maximum profit for the producer is taken. The model is exemplified by a concentrated EPS. The computations have been performed using the MATLAB program.

  20. Reliability Analysis of Free Jet Scour Below Dams

    Chuanqi Li


    Full Text Available Current formulas for calculating scour depth below of a free over fall are mostly deterministic in nature and do not adequately consider the uncertainties of various scouring parameters. A reliability-based assessment of scour, taking into account uncertainties of parameters and coefficients involved, should be performed. This paper studies the reliability of a dam foundation under the threat of scour. A model for calculating the reliability of scour and estimating the probability of failure of the dam foundation subjected to scour is presented. The Maximum Entropy Method is applied to construct the probability density function (PDF of the performance function subject to the moment constraints. Monte Carlo simulation (MCS is applied for uncertainty analysis. An example is considered, and there liability of its scour is computed, the influence of various random variables on the probability failure is analyzed.

  1. Decomposition Techniques and Effective Algorithms in Reliability-Based Optimization

    Enevoldsen, I.; Sørensen, John Dalsgaard


    The common problem of an extensive number of limit state function calculations in the various formulations and applications of reliability-based optimization is treated. It is suggested to use a formulation based on decomposition techniques so the nested two-level optimization problem can be solved...

  2. On the Reliability of Unit Value Ratios in International Comparisons

    Timmer, Marcel P.


    In this paper reliability indicators are developed for the Laspeyres and Paasche index type currency conversion factors used in the industry of origin approach to international comparisons of output. Given the fact that these conversion factors are calculated on basis of a sampling technique, sampli

  3. Study of the Service Reliability of Machines Based on Safety


    From the point of safety being the basic requirement of machine operation, equivalent failure number, which is employed to replace the actual statistical failure number, is introduced. Calculating theory of service reliability indexes of machines based on safety is developed. The method proposed in this paper can reflect the damage degree of failure.

  4. Statistical Analysis of Human Reliability of Armored Equipment

    LIU Wei-ping; CAO Wei-guo; REN Jing


    Human errors of seven types of armored equipment, which occur during the course of field test, are statistically analyzed. The human error-to-armored equipment failure ratio is obtained. The causes of human errors are analyzed. The distribution law of human errors is acquired. The ratio of human errors and human reliability index are also calculated.

  5. The reliability and validity of video analysis for the assessment of the clinical signs of concussion in Australian football.

    Makdissi, Michael; Davis, Gavin


    The objective of this study was to determine the reliability and validity of identifying clinical signs of concussion using video analysis in Australian football. Prospective cohort study. All impacts and collisions potentially resulting in a concussion were identified during 2012 and 2013 Australian Football League seasons. Consensus definitions were developed for clinical signs associated with concussion. For intra- and inter-rater reliability analysis, two experienced clinicians independently assessed 102 randomly selected videos on two occasions. Sensitivity, specificity, positive and negative predictive values were calculated based on the diagnosis provided by team medical staff. 212 incidents resulting in possible concussion were identified in 414 Australian Football League games. The intra-rater reliability of the video-based identification of signs associated with concussion was good to excellent. Inter-rater reliability was good to excellent for impact seizure, slow to get up, motor incoordination, ragdoll appearance (2 of 4 analyses), clutching at head and facial injury. Inter-rater reliability for loss of responsiveness and blank and vacant look was only fair and did not reach statistical significance. The feature with the highest sensitivity was slow to get up (87%), but this sign had a low specificity (19%). Other video signs had a high specificity but low sensitivity. Blank and vacant look (100%) and motor incoordination (81%) had the highest positive predictive value. Video analysis may be a useful adjunct to the side-line assessment of a possible concussion. Video analysis however should not replace the need for a thorough multimodal clinical assessment. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  6. An Overview of the Reliability and Availability Data System (RADS)

    T. E. Wierman; K. J. Kvarfordt; S. A. Eide; D. M. Rasmuson


    The Reliability and Availability Data System (RADS) is a database and analysis code, developed by the Idaho National Engineering and Environmental Laboratory (INEEL) for the U.S. Nuclear Regulatory Commission (USNRC). The code is designed to estimate industry and plant-specific reliability and availability parameters for selected components in risk-important systems and initiating events for use in risk-informed applications. The RADS tool contains data and information based on actual operating experience from U.S. commercial nuclear power plants. The data contained in RADS is kept up-to-date by loading the most current quarter's Equipment Performance and Information Exchange (EPIX) data and by yearly lods of initiating event data from licensee event reports (LERS). The reliability parameters estimated by RADS are (1) probability of failure on demand, (2) failure rate during operation (used to calculate failure to run probability) and (3) time trends in reliability parameters.

  7. Capacity Reliability of Signalized Intersections with Mixed Traffic Conditions

    CHEN Xiaoming; SHAO Chunfu; LI Da; DONG Chunjiao


    The reliability of capacity of signalized intersections in mixed traffic conditions involving vehicles, bicycles, and pedestrians was investigated to complete the conventional, deterministic capacity calculations. Simulations using VISSIM provided estimates of capacity distributions, and demonstrated the effects of the analysis intervals on the distributions. With the random vehicle arrivals taken into account, a capacity reli-ability assessment method was given as a function. Assessments were also performed regarding the effects of the conflicting pedestrian and bicycle volumes on capacity reliability. The simulation indicates that the pe-destrians and bicycles result in greater random fluctuations of exclusive tuming lane capacities, but have less effect on the variability of shared lane capacities. Normal distributions can be used to model the capaci-ties for intervals not less than 10 min. At higher vehicular volumes, the capacity reliability is more sensitive to the mean and standard deviation of the pedestrian and bicycle volumes.

  8. Reliable predictions of waste performance in a geologic repository

    Pigford, T.H.; Chambre, P.L.


    Establishing reliable estimates of long-term performance of a waste repository requires emphasis upon valid theories to predict performance. Predicting rates that radionuclides are released from waste packages cannot rest upon empirical extrapolations of laboratory leach data. Reliable predictions can be based on simple bounding theoretical models, such as solubility-limited bulk-flow, if the assumed parameters are reliably known or defensibly conservative. Wherever possible, performance analysis should proceed beyond simple bounding calculations to obtain more realistic - and usually more favorable - estimates of expected performance. Desire for greater realism must be balanced against increasing uncertainties in prediction and loss of reliability. Theoretical predictions of release rate based on mass-transfer analysis are bounding and the theory can be verified. Postulated repository analogues to simulate laboratory leach experiments introduce arbitrary and fictitious repository parameters and are shown not to agree with well-established theory. 34 refs., 3 figs., 2 tabs.

  9. Reliability Analysis of Wireless Sensor Networks Using Markovian Model

    Jin Zhu


    Full Text Available This paper investigates reliability analysis of wireless sensor networks whose topology is switching among possible connections which are governed by a Markovian chain. We give the quantized relations between network topology, data acquisition rate, nodes' calculation ability, and network reliability. By applying Lyapunov method, sufficient conditions of network reliability are proposed for such topology switching networks with constant or varying data acquisition rate. With the conditions satisfied, the quantity of data transported over wireless network node will not exceed node capacity such that reliability is ensured. Our theoretical work helps to provide a deeper understanding of real-world wireless sensor networks, which may find its application in the fields of network design and topology control.

  10. 78 FR 38311 - Reliability Technical Conference Agenda


    ..., Fix, Track, and Report program enhanced reliability? b. What is the status of the NERC Reliability... Energy Regulatory Commission Reliability Technical Conference Agenda Reliability Technical Docket No. AD13-6-000 Conference. North American Electric Docket No. RC11-6-004 Reliability Corporation....

  11. HST Cycle 19 Exposure Time Calculators

    York, Brian Andrew; Diaz, R. I.; Busko, I.; Greenfield, P.; Laidler, V.; Miller, T.; Sienkiewicz, M.; Sosey, M.


    The Exposure Time Calculator (ETC) is a web-based application that assists users in calculating the exposure time needed for their HST observations, or the Signal-to-Noice Ratio (SNR) they can attain with a given HST observing time. These quantities are key for the preparation of proposals and observations during Phase I and Phase II of the proposing cycle and therefore have to be sufficiently accurate for each of the supported observing modes of all the HST instruments. Developing a general tool that shares communality among the different instruments is complicated, not only form the point of view of attaining accuracy of the calculations but also regarding reliability, portability, and maintainability. We are currently developing a new version of the ETC for Cycle 19 in Python to improve these qualities and to provide a basis for JWST Exposure Time Calculators. This poster describes the improvements over the previous ETC and the current status of the new version.

  12. Study on Reliability Level of Crack Width Calculation Formula for Outer Wrapped Concrete Structures of Steel Lined Reinforced Concrete Penstock%钢衬钢筋混凝土管外包混凝土裂缝宽度计算公式安全度水平研究

    李扬; 侯建国


    By introducing the concept of equivalent guarantee rate, the analysis and comparison of both the accuracy and safety level were conducted among different crack width calculation formulas for outer wrapped concrete structures of steel lined reinforced concrete penstock. The results show that the accuracy of formula given by design code Ⅱ-780-83 of Former Soviet Union and Dong Zheren are relatively high and the equivalent guarantee rate of these two formulas are respectively 80. 54% and 92. 38%. Then two schemes of crack width calculation method were proposed for outer wrapped concrete structures. The first scheme is to apply the formula given in design code Ⅱ-780-83 of Former Soviet Union and the calculation results gotten from this formula should be multiplied with factor 1. 2. The second scheme is to apply the formula given by Dong Zheren while the average crack spacing should be calculated by the formula proposed by Guo Mao-hua.%通过引入等效保证率概念,对现有不同钢衬钢筋混凝土管外包混凝土结构裂缝宽度计算公式的计算精度以及安全度水平进行了分析比较.结果表明,前苏联∏-780-83公式和董哲仁公式计算精度相对较高,其等效保证率分别达到了80.54%和92.38%.提出了两套钢衬钢筋混凝土管外包混凝土结构裂缝宽度计算建议方案:方案一为采用前苏联∏-780-83中裂缝宽度计算公式计算,将计算值乘以增大系数1.2;方案二为采用董哲仁建议的裂缝宽度计算公式计算,其中平均裂缝间距改用国茂华公式.

  13. Theoretical Calculations of Atomic Data for Spectroscopy

    Bautista, Manuel A.


    Several different approximations and techniques have been developed for the calculation of atomic structure, ionization, and excitation of atoms and ions. These techniques have been used to compute large amounts of spectroscopic data of various levels of accuracy. This paper presents a review of these theoretical methods to help non-experts in atomic physics to better understand the qualities and limitations of various data sources and assess how reliable are spectral models based on those data.

  14. Advancing methods for reliably assessing motivational interviewing fidelity using the motivational interviewing skills code.

    Lord, Sarah Peregrine; Can, Doğan; Yi, Michael; Marin, Rebeca; Dunn, Christopher W; Imel, Zac E; Georgiou, Panayiotis; Narayanan, Shrikanth; Steyvers, Mark; Atkins, David C


    The current paper presents novel methods for collecting MISC data and accurately assessing reliability of behavior codes at the level of the utterance. The MISC 2.1 was used to rate MI interviews from five randomized trials targeting alcohol and drug use. Sessions were coded at the utterance-level. Utterance-based coding reliability was estimated using three methods and compared to traditional reliability estimates of session tallies. Session-level reliability was generally higher compared to reliability using utterance-based codes, suggesting that typical methods for MISC reliability may be biased. These novel methods in MI fidelity data collection and reliability assessment provided rich data for therapist feedback and further analyses. Beyond implications for fidelity coding, utterance-level coding schemes may elucidate important elements in the counselor-client interaction that could inform theories of change and the practice of MI. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Incorporating Cyber Layer Failures in Composite Power System Reliability Evaluations

    Yuqi Han


    Full Text Available This paper proposes a novel approach to analyze the impacts of cyber layer failures (i.e., protection failures and monitoring failures on the reliability evaluation of composite power systems. The reliability and availability of the cyber layer and its protection and monitoring functions with various topologies are derived based on a reliability block diagram method. The availability of the physical layer components are modified via a multi-state Markov chain model, in which the component protection and monitoring strategies, as well as the cyber layer topology, are simultaneously considered. Reliability indices of composite power systems are calculated through non-sequential Monte-Carlo simulation. Case studies demonstrate that operational reliability downgrades in cyber layer function failure situations. Moreover, protection function failures have more significant impact on the downgraded reliability than monitoring function failures do, and the reliability indices are especially sensitive to the change of the cyber layer function availability in the range from 0.95 to 1.


    Su Xihong; Liu Hongwei; Wu Zhibo; Yang Xiaozong; Zuo Decheng


    Reliability is one of the most critical properties of software system.System deployment architecture is the allocation of system software components on host nodes.Software Architecture (SA)based software deployment models help to analyze reliability of different deployments.Though many approaches for architecture-based reliability estimation exist,little work has incorporated the influence of system deployment and hardware resources into reliability estimation.There are many factors influencing system deployment.By translating the multi-dimension factors into degree matrix of component dependence,we provide the definition of component dependence and propose a method of calculating system reliability of deployments.Additionally,the parameters that influence the optimal deployment may change during system execution.The existing software deployment architecture may be ill-suited for the given environment,and the system needs to be redeployed to improve reliability.An approximate algorithm,A*_D,to increase system reliability is presented.When the number of components and host nodes is relative large,experimental results show that this algorithm can obtain better deployment than stochastic and greedy algorithms.

  17. Requalification of offshore structures. Reliability analysis of platform

    Bloch, A.; Dalsgaard Soerensen, J. [Aalborg Univ. (Denmark)


    A preliminary reliability analysis has been performed for an example platform. In order to model the structural response such that it is possible to calculate reliability indices, approximate quadratic response surfaces have been determined for cross-sectional forces. Based on a deterministic, code-based analysis the elements and joints which can be expected to be the most critical are selected and response surfaces are established for the cross-sectional forces in those. A stochastic model is established for the uncertain variables. The reliability analysis shows that with this stochastic model the smallest reliability indices for elements are about 3.9. The reliability index for collapse (pushover) is estimated to 6.7 and the reliability index for fatigue failure using a crude model is for the expected most critical detail estimated to 3.2, corresponding to the accumulated damage during the design lifetime of the platform. These reliability indices are considered to be reasonable compared with values recommended by e.g. ISO. The most important stochastic variables are found to be the wave height and the drag coefficient (including the model uncertainty related to estimation of wave forces on the platform). (au)

  18. Assessment on reliability of water quality in water distribution systems

    伍悦滨; 田海; 王龙岩


    Water leaving the treatment works is usually of a high quality but its properties change during the transportation stage. Increasing awareness of the quality of the service provided within the water industry today and assessing the reliability of the water quality in a distribution system has become a major significance for decision on system operation based on water quality in distribution networks. Using together a water age model, a chlorine decay model and a model of acceptable maximum water age can assess the reliability of the water quality in a distribution system. First, the nodal water age values in a certain complex distribution system can be calculated by the water age model. Then, the acceptable maximum water age value in the distribution system is obtained based on the chlorine decay model. The nodes at which the water age values are below the maximum value are regarded as reliable nodes. Finally, the reliability index on the percentile weighted by the nodal demands reflects the reliability of the water quality in the distribution system. The approach has been applied in a real water distribution network. The contour plot based on the water age values determines a surface of the reliability of the water quality. At any time, this surface is used to locate high water age but poor reliability areas, which identify parts of the network that may be of poor water quality. As a result, the contour water age provides a valuable aid for a straight insight into the water quality in the distribution system.

  19. Designing Tone Reservation PAR Reduction

    Johansson Albin


    Full Text Available Tone reservation peak-to-average (PAR ratio reduction is an established area when it comes to bringing down signal peaks in multicarrier (DMT or OFDM systems. When designing such a system, some questions often arise about PAR reduction. Is it worth the effort? How much can it give? How much does it give depending on the parameter choices? With this paper, we attempt to answer these questions without resolving to extensive simulations for every system and every parameter choice. From a specification of the allowed spectrum, for instance prescribed by a standard, including a PSD-mask and a number of tones, we analytically predict achievable PAR levels, and thus implicitly suggest parameter choices. We use the ADSL2 and ADSL2+ systems as design examples.

  20. Reserved-Length Prefix Coding

    Baer, Michael B


    Huffman coding finds an optimal prefix code for a given probability mass function. Consider situations in which one wishes to find an optimal code with the restriction that all codewords have lengths that lie in a user-specified set of lengths (or, equivalently, no codewords have lengths that lie in a complementary set). This paper introduces a polynomial-time dynamic programming algorithm that finds optimal codes for this reserved-length prefix coding problem. This has applications to quickly encoding and decoding lossless codes. In addition, one modification of the approach solves any quasiarithmetic prefix coding problem, while another finds optimal codes restricted to the set of codes with g codeword lengths for user-specified g (e.g., g=2).

  1. Z' reservation at LEP2

    Montagna, G.; Piccinini, F.; Renard, F.M.; Verzegnassi, C.


    We consider the possibility that one extra Z\\equiv Z' exists with arbitrary mass and fermion couplings that do not violate (charged) lepton universality. We show that, in such a situation, a functional relationship is generated between the \\underline{deviations} from the SM values of three leptonic observables of two-fermion production at future e^+e^- colliders that is completely independent of the values of the Z' mass and couplings. This selects a certain region in the 3-d space of the deviations that is \\underline{characteristic} of the model (Z' "reservation"). As a specific and relevant example, we show the picture that would emerge at LEP2 under realistic experimental conditions.

  2. Calculators and Polynomial Evaluation.

    Weaver, J. F.

    The intent of this paper is to suggest and illustrate how electronic hand-held calculators, especially non-programmable ones with limited data-storage capacity, can be used to advantage by students in one particular aspect of work with polynomial functions. The basic mathematical background upon which calculator application is built is summarized.…

  3. Reliability Based Ship Structural Design

    Dogliani, M.; Østergaard, C.; Parmentier, G.;


    with developments of models of load effects and of structural collapse adopted in reliability formulations which aim at calibrating partial safety factors for ship structural design. New probabilistic models of still-water load effects are developed both for tankers and for containerships. New results are presented......This paper deals with the development of different methods that allow the reliability-based design of ship structures to be transferred from the area of research to the systematic application in current design. It summarises the achievements of a three-year collaborative research project dealing...... structure of several tankers and containerships. The results of the reliability analysis were the basis for the definition of a target safety level which was used to asses the partial safety factors suitable for in a new design rules format to be adopted in modern ship structural design. Finally...

  4. Reliability Modeling of Wind Turbines

    Kostandyan, Erik

    Cost reductions for offshore wind turbines are a substantial requirement in order to make offshore wind energy more competitive compared to other energy supply methods. During the 20 – 25 years of wind turbines useful life, Operation & Maintenance costs are typically estimated to be a quarter...... the actions should be made and the type of actions requires knowledge on the accumulated damage or degradation state of the wind turbine components. For offshore wind turbines, the action times could be extended due to weather restrictions and result in damage or degradation increase of the remaining...... for Operation & Maintenance planning. Concentrating efforts on development of such models, this research is focused on reliability modeling of Wind Turbine critical subsystems (especially the power converter system). For reliability assessment of these components, structural reliability methods are applied...

  5. Reliability Assessment of Wind Turbines

    Sørensen, John Dalsgaard


    Wind turbines can be considered as structures that are in between civil engineering structures and machines since they consist of structural components and many electrical and machine components together with a control system. Further, a wind turbine is not a one-of-a-kind structure...... but manufactured in series production based on many component tests, some prototype tests and zeroseries wind turbines. These characteristics influence the reliability assessment where focus in this paper is on the structural components. Levelized Cost Of Energy is very important for wind energy, especially when...... comparing to other energy sources. Therefore much focus is on cost reductions and improved reliability both for offshore and onshore wind turbines. The wind turbine components should be designed to have sufficient reliability level with respect to both extreme and fatigue loads but also not be too costly...

  6. Reliability assessment of Wind turbines

    Sørensen, John Dalsgaard


    Wind turbines can be considered as structures that are in between civil engineering structures and machines since they consist of structural components and many electrical and machine components together with a control system. Further, a wind turbine is not a one-of-a-kind structure...... but manufactured in series production based on many component tests, some prototype tests and zeroseries wind turbines. These characteristics influence the reliability assessment where focus in this paper is on the structural components. Levelized Cost Of Energy is very important for wind energy, especially when...... comparing to other energy sources. Therefore much focus is on cost reductions and improved reliability both for offshore and onshore wind turbines. The wind turbine components should be designed to have sufficient reliability level with respect to both extreme and fatigue loads but also not be too costly...

  7. Reliability of Wave Energy Converters

    Ambühl, Simon

    . Structural reliability considerations and optimizations impact operation and maintenance (O&M) costs as well as the initial investment costs. Furthermore, there is a control system for WEC applications which defines the harvested energy but also the loads onto the structure. Therefore, extreme loads but also...... WEPTOS. Calibration of safety factors are performed for welded structures at theWavestar device including different control systems for harvesting energy from waves. In addition, a case study of different O&M strategies for WECs is discussed, and an example of reliability-based structural optimization......There are many different working principles for wave energy converters (WECs) which are used to produce electricity from waves. In order for WECs to become successful and more competitive to other renewable electricity sources, the consideration of the structural reliability of WECs is essential...

  8. Reliability Characteristics of Power Plants

    Zbynek Martinek


    Full Text Available This paper describes the phenomenon of reliability of power plants. It gives an explanation of the terms connected with this topic as their proper understanding is important for understanding the relations and equations which model the possible real situations. The reliability phenomenon is analysed using both the exponential distribution and the Weibull distribution. The results of our analysis are specific equations giving information about the characteristics of the power plants, the mean time of operations and the probability of failure-free operation. Equations solved for the Weibull distribution respect the failures as well as the actual operating hours. Thanks to our results, we are able to create a model of dynamic reliability for prediction of future states. It can be useful for improving the current situation of the unit as well as for creating the optimal plan of maintenance and thus have an impact on the overall economics of the operation of these power plants.

  9. Component reliability for electronic systems

    Bajenescu, Titu-Marius I


    The main reason for the premature breakdown of today's electronic products (computers, cars, tools, appliances, etc.) is the failure of the components used to build these products. Today professionals are looking for effective ways to minimize the degradation of electronic components to help ensure longer-lasting, more technically sound products and systems. This practical book offers engineers specific guidance on how to design more reliable components and build more reliable electronic systems. Professionals learn how to optimize a virtual component prototype, accurately monitor product reliability during the entire production process, and add the burn-in and selection procedures that are the most appropriate for the intended applications. Moreover, the book helps system designers ensure that all components are correctly applied, margins are adequate, wear-out failure modes are prevented during the expected duration of life, and system interfaces cannot lead to failure.

  10. New Approaches to Reliability Assessment

    Ma, Ke; Wang, Huai; Blaabjerg, Frede


    of energy. New approaches for reliability assessment are being taken in the design phase of power electronics systems based on the physics-of-failure in components. In this approach, many new methods, such as multidisciplinary simulation tools, strength testing of components, translation of mission profiles......Power electronics are facing continuous pressure to be cheaper and smaller, have a higher power density, and, in some cases, also operate at higher temperatures. At the same time, power electronics products are expected to have reduced failures because it is essential for reducing the cost......, and statistical analysis, are involved to enable better prediction and design of reliability for products. This article gives an overview of the new design flow in the reliability engineering of power electronics from the system-level point of view and discusses some of the emerging needs for the technology...

  11. Structural Optimization with Reliability Constraints

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle


    During the last 25 years considerable progress has been made in the fields of structural optimization and structural reliability theory. In classical deterministic structural optimization all variables are assumed to be deterministic. Due to the unpredictability of loads and strengths of actual...... structures it is now widely accepted that structural problems are non-deterministic. Therefore, some of the variables have to be modelled as random variables/processes and a reliability-based design philosophy should be used, Comell [1], Moses [2], Ditlevsen [3] and Thoft-Christensen & Baker [ 4......]. In this paper we consider only structures which can be modelled as systems of elasto-plastic elements, e.g. frame and truss structures. In section 2 a method to evaluate the reliability of such structural systems is presented. Based on a probabilistic point of view a modern structural optimization problem...

  12. An Approach to Online Reliability Evaluation and Prediction of Mechanical Transmission Components

    Matthias Maisch; Bernd Bertsche; Ralf Hettich


    New development trends in electronic operating data logging systems enable classification, recording and storage of load spectrums of mechanical transmission components during usage. Based on this fact, the application of online reliability evaluation and reliability prediction procedures are presented. Different methods are considered to calculate reliability, depending on actual load spectrum and a Wohler curve. The prediction of a reliability trend is analyzed by the application of time series models. For this purpose, exponential smoothing model, regression model, and the ARIMA model are considered to evaluate data and predict an decreasing reliability trends during usage.

  13. Design of Accelerated Reliability Test for CNC Motorized Spindle Based on Vibration Signal

    Chen Chao


    Full Text Available Motorized spindle is the key functional component of CNC machining centers which is a mechatronics system with long life and high reliability. The reliability test cycle of motorized spindle is too long and infeasible. This paper proposes a new accelerated test for reliability evaluation of motorized spindle. By field reliability test, authors collect and calculate the load data including rotational speed, cutting force and torque. Load spectrum distribution law is analyzed. And authors design a test platform to apply the load spectrum. A new method to define the fuzzy acceleration factor based on the vibration signal is proposed. Then the whole test plan of accelerated reliability test is done.

  14. Long-Term Reserve Expansion of Power Systems With High Wind Power Penetration Using Universal Generating Function Methods

    DING, YI; Wang, Peng; Goel, Lalit


    In a power system with high wind power penetration, reliability based reserve expansion is a major problem of system planning and operation due to the uncertainty and fast fluctuation of wind speeds. This paper studied the impact of high wind power penetration on the system reserve and reliabilit...... is proposed to determine the conventional reserve required for power systems with high wind power penetration. The IEEE-RTS has been modified to illustrate the applications of the proposed method.......In a power system with high wind power penetration, reliability based reserve expansion is a major problem of system planning and operation due to the uncertainty and fast fluctuation of wind speeds. This paper studied the impact of high wind power penetration on the system reserve and reliability...... reliabilities. The effect of transmission network on customer reliabilities is also considered in the system UGF. The power output models of wind turbine generators in a wind farm considering wind speed correlation and un-correlation are developed, respectively. A reliability-based reserve expansion method...

  15. ERP Reliability Analysis (ERA) Toolbox: An open-source toolbox for analyzing the reliability of event-related brain potentials.

    Clayson, Peter E; Miller, Gregory A


    Generalizability theory (G theory) provides a flexible, multifaceted approach to estimating score reliability. G theory's approach to estimating score reliability has important advantages over classical test theory that are relevant for research using event-related brain potentials (ERPs). For example, G theory does not require parallel forms (i.e., equal means, variances, and covariances), can handle unbalanced designs, and provides a single reliability estimate for designs with multiple sources of error. This monograph provides a detailed description of the conceptual framework of G theory using examples relevant to ERP researchers, presents the algorithms needed to estimate ERP score reliability, and provides a detailed walkthrough of newly-developed software, the ERP Reliability Analysis (ERA) Toolbox, that calculates score reliability using G theory. The ERA Toolbox is open-source, Matlab software that uses G theory to estimate the contribution of the number of trials retained for averaging, group, and/or event types on ERP score reliability. The toolbox facilitates the rigorous evaluation of psychometric properties of ERP scores recommended elsewhere in this special issue.

  16. Estimating cognitive reserve in healthy adults using the Cognitive Reserve Scale.

    Irene León

    Full Text Available The concept of cognitive reserve emerged from observed disparities between brain pathology and clinical symptoms. It may explain better neuropsychological performance in healthy individuals. The objectives of this study were to measure reserve in healthy subjects using a new Cognitive Reserve Scale (CRS, analyze the internal consistency of the CRS, and analyze validity evidence. A total of 117 healthy individuals were divided into two groups: 87 adults (aged 18-64 years and 30 elderly adults (≥65 years. All subjects completed the CRS and a comprehensive neuropsychological battery. The internal consistency of the scale was satisfactory (α = 0.77. No significant differences were observed between genders (t = 0.51, p = 0.611, and age was corrected by averaging the CRS score. The study of validity evidence showed that education affected the CRS (t = -2.98, p = 0.004, partial h2 = 0.07 and there was no significant relationship between the CRS and IQ (r = 0.09, p = 0.33. Occupational attainment and the CRS were not related (F2,116 = 0.11, p = 0.898. In line with previous studies on reserve, heterogeneity was observed in the analyses of relationships between the CRS and cognitive performance. There were significant relationships between CRS score and the Verbal Learning Spanish-Complutense Test last trial (r = 0.24, p = 0.009, sum (r = 0.32, p = 0.000, short-term (r = 0.29, p = 0.002 and long-term memory (r = 0.22, p = 0.018, Matrix Reasoning subtest (r = 0.20, p = 0.027 and Block Design subtest (r = 0.20, p = 0.029. No other neuropsychological variables correlated with the CRS (p>0.05. The CRS is a reliable instrument that reflects the frequency of participation in brain-stimulating activities across the lifetime. The associations between the CRS and education and neuropsychological performance support validity evidence.

  17. Reliability-based optimization of engineering structures

    Sørensen, John Dalsgaard


    The theoretical basis for reliability-based structural optimization within the framework of Bayesian statistical decision theory is briefly described. Reliability-based cost benefit problems are formulated and exemplitied with structural optimization. The basic reliability-based optimization prob...

  18. Metrological Reliability of Medical Devices

    Costa Monteiro, E.; Leon, L. F.


    The prominent development of health technologies of the 20th century triggered demands for metrological reliability of physiological measurements comprising physical, chemical and biological quantities, essential to ensure accurate and comparable results of clinical measurements. In the present work, aspects concerning metrological reliability in premarket and postmarket assessments of medical devices are discussed, pointing out challenges to be overcome. In addition, considering the social relevance of the biomeasurements results, Biometrological Principles to be pursued by research and innovation aimed at biomedical applications are proposed, along with the analysis of their contributions to guarantee the innovative health technologies compliance with the main ethical pillars of Bioethics.

  19. Reliability Assessment of Concrete Bridges

    Thoft-Christensen, Palle; Middleton, C. R.

    This paper is partly based on research performed for the Highways Agency, London, UK under the project DPU/9/44 "Revision of Bridge Assessment Rules Based on Whole Life Performance: concrete bridges". It contains the details of a methodology which can be used to generate Whole Life (WL) reliability...... profiles. These WL reliability profiles may be used to establish revised rules for concrete bridges. This paper is to some extend based on Thoft-Christensen et. al. [1996], Thoft-Christensen [1996] et. al. and Thoft-Christensen [1996]....

  20. Reliability Management for Information System

    李睿; 俞涛; 刘明伦


    An integrated intelligent management is presented to help organizations manage many heterogeneous resources in their information system. A general architecture of management for information system reliability is proposed, and the architecture from two aspects, process model and hierarchical model, described. Data mining techniques are used in data analysis. A data analysis system applicable to real-time data analysis is developed by improved data mining on the critical processes. The framework of the integrated management for information system reliability based on real-time data mining is illustrated, and the development of integrated and intelligent management of information system discussed.

  1. Marine reserves: size and age do matter.

    Claudet, Joachim; Osenberg, Craig W; Benedetti-Cecchi, Lisandro; Domenici, Paolo; García-Charton, José-Antonio; Pérez-Ruzafa, Angel; Badalamenti, Fabio; Bayle-Sempere, Just; Brito, Alberto; Bulleri, Fabio; Culioli, Jean-Michel; Dimech, Mark; Falcón, Jesús M; Guala, Ivan; Milazzo, Marco; Sánchez-Meca, Julio; Somerfield, Paul J; Stobart, Ben; Vandeperre, Frédéric; Valle, Carlos; Planes, Serge


    Marine reserves are widely used throughout the world to prevent overfishing and conserve biodiversity, but uncertainties remain about their optimal design. The effects of marine reserves are heterogeneous. Despite theoretical findings, empirical studies have previously found no effect of size on the effectiveness of marine reserves in protecting commercial fish stocks. Using 58 datasets from 19 European marine reserves, we show that reserve size and age do matter: Increasing the size of the no-take zone increases the density of commercial fishes within the reserve compared with outside; whereas the size of the buffer zone has the opposite effect. Moreover, positive effects of marine reserve on commercial fish species and species richness are linked to the time elapsed since the establishment of the protection scheme. The reserve size-dependency of the response to protection has strong implications for the spatial management of coastal areas because marine reserves are used for spatial zoning.

  2. Subendocardial viability ratio as an index of impaired coronary flow reserve in hypertensives without significant coronary artery stenoses.

    Tsiachris, D; Tsioufis, C; Syrseloudis, D; Roussos, D; Tatsis, I; Dimitriadis, K; Toutouzas, K; Tsiamis, E; Stefanadis, C


    Subendocardial viability ratio (SEVR), calculated through pulse wave analysis, is an index of myocardial oxygen supply and demand. Our aim was to evaluate the relationship between coronary flow reserve (CFR) and SEVR in 36 consecutive untreated hypertensives (aged 57.9 years, 12 males, all Caucasian) with indications of myocardial ischaemia and normal coronary arteries in coronary angiography. CFR was calculated by a 0.014-inch Doppler guidewire (Flowire, Volcano, San Diego, CA, USA) in response to bolus intracoronary administration of adenosine (30-60 μg). SEVR was calculated by radial applanation tonometry, while diastolic function was evaluated by means of transmitral flow and tissue Doppler imaging. Hypertensive patients with low CFR (n=24) compared with those with normal CFR (n=12) exhibited significantly decreased SEVR by 24.5% (P=0.002). In hypertensives with low CFR, CFR was correlated with SEVR (r=0.651, P=0.001). After applying multivariate linear regression analysis, age, left ventricular mass index, Em/Am, 24-h diastolic blood pressure (BP) and SEVR turned out to be the only independent predictors of CFR (adjusted R(2)=0.718). Estimation of SEVR by using applanation tonometry may provide a reliable tool for the assessment of coronary microcirculation in essential hypertensives with indications of myocardial ischaemia and normal coronary arteries.

  3. A Comprehensive Comparison of Current Operating Reserve Methodologies

    Krad, Ibrahim; Ibanez, Eduardo; Gao, Wenzhong


    Electric power systems are currently experiencing a paradigm shift from a traditionally static system to a system that is becoming increasingly more dynamic and variable. Emerging technologies are forcing power system operators to adapt to their performance characteristics. These technologies, such as distributed generation and energy storage systems, have changed the traditional idea of a distribution system with power flowing in one direction into a distribution system with bidirectional flows. Variable generation, in the form of wind and solar generation, also increases the variability and uncertainty in the system. As such, power system operators are revisiting the ways in which they treat this evolving power system, namely by modifying their operating reserve methodologies. This paper intends to show an in-depth analysis on different operating reserve methodologies and investigate their impacts on power system reliability and economic efficiency.

  4. Multicell LiSOCl sub 2 reserve battery

    Baldwin, A. R.; Garoutte, K. F.

    Recent development work on reverse lithium thionyl chloride (RLTC) batteries at SNLA and Honeywell has included safety and performance evaluations. The RLTC battery is being considered for applications that were traditionally fulfilled by state-of-the-art thermal batteries and reserve silver oxide zinc electrochemical systems. These applications typically demand a reserve battery having a rapid voltage rise, high reliability, operational safety and useful active lifetime ranging from minutes to hours. The RLTC work reported here was directed toward a power battery capable of meeting or exceeding the design requirements. Performance and safety test data indicate that the RLTC battery may be better suited than thermal batteries for some long-life applications. A comparison between Li(Si)/FeS2 thermal battery and an RLTC battery, both of which were designed to fulfill the requirements is presented.

  5. Introducing optional reserve ratios in Hungary

    Lóránt Varga


    As of the reserve maintenance period commencing in November 2010, Hungarian credit institutions will be free to decide whether to apply the previously valid 2% reserve ratio, or to apply a higher mandatory reserve ratio. Credit institutions required to hold reserves may select from reserve ratios of 2, 3, 4 and 5%, and may change their decision on a semi-annual basis. In line with the international best practice, the purpose of the MNB’s reserve requirement system is to support credit institu...



  7. Reliability of quantitative content analyses

    Enschot-van Dijk, R. van


    Reliable coding of stimuli is a daunting task that often yields unsatisfactory results. This paper discusses a case study in which tropes (e.g., metaphors, puns) in TV commercials were analyzed as well the extent and location of verbal and visual anchoring (i.e., explanation) of these tropes. After

  8. Wind turbine reliability database update.

    Peters, Valerie A.; Hill, Roger Ray; Stinebaugh, Jennifer A.; Veers, Paul S.


    This report documents the status of the Sandia National Laboratories' Wind Plant Reliability Database. Included in this report are updates on the form and contents of the Database, which stems from a fivestep process of data partnerships, data definition and transfer, data formatting and normalization, analysis, and reporting. Selected observations are also reported.

  9. Photovoltaic performance and reliability workshop

    Kroposki, B


    This proceedings is the compilation of papers presented at the ninth PV Performance and Reliability Workshop held at the Sheraton Denver West Hotel on September 4--6, 1996. This years workshop included presentations from 25 speakers and had over 100 attendees. All of the presentations that were given are included in this proceedings. Topics of the papers included: defining service lifetime and developing models for PV module lifetime; examining and determining failure and degradation mechanisms in PV modules; combining IEEE/IEC/UL testing procedures; AC module performance and reliability testing; inverter reliability/qualification testing; standardization of utility interconnect requirements for PV systems; need activities to separate variables by testing individual components of PV systems (e.g. cells, modules, batteries, inverters,charge controllers) for individual reliability and then test them in actual system configurations; more results reported from field experience on modules, inverters, batteries, and charge controllers from field deployed PV systems; and system certification and standardized testing for stand-alone and grid-tied systems.


    Dr Obe

    Evaluation of the reliability of a primary cell took place in three stages: 192 cells went through a ... CCV - Closed Circuit Voltage, the voltage at the terminals of a battery when it is under an electrical ... Cylindrical spirally wound cells have the.

  11. Finding Reliable Health Information Online

    ... at NHGRI About About the Institute Budget and Financial Information Divisions Director's Page How to Contact Us Institute ... una búsqueda saludable en Internet Finding Reliable Health Information Online As Internet users quickly discover, an enormous amount of health information ...

  12. Reliability of subjective wound assessment

    M.C.T. Bloemen; P.P.M. van Zuijlen; E. Middelkoop


    Introduction: Assessment of the take of split-skin graft and the rate of epithelialisation are important parameters in burn surgery. Such parameters are normally estimated by the clinician in a bedside procedure. This study investigates whether this subjective assessment is reliable for graft take a

  13. Fatigue Reliability under Random Loads

    Talreja, R.


    , with the application of random loads, the initial homogeneous distribution of strength changes to a two-component distribution, reflecting the two-stage fatigue damage. In the crack initiation stage, the strength increases initially and then decreases, while an abrupt decrease of strength is seen in the crack...... propagation stage. The consequences of this behaviour on the fatigue reliability are discussed....

  14. Reliability Analysis of Money Habitudes

    Delgadillo, Lucy M.; Bushman, Brittani S.


    Use of the Money Habitudes exercise has gained popularity among various financial professionals. This article reports on the reliability of this resource. A survey administered to young adults at a western state university was conducted, and each Habitude or "domain" was analyzed using Cronbach's alpha procedures. Results showed all six…

  15. The Reliability of College Grades

    Beatty, Adam S.; Walmsley, Philip T.; Sackett, Paul R.; Kuncel, Nathan R.; Koch, Amanda J.


    Little is known about the reliability of college grades relative to how prominently they are used in educational research, and the results to date tend to be based on small sample studies or are decades old. This study uses two large databases (N > 800,000) from over 200 educational institutions spanning 13 years and finds that both first-year…

  16. Reliability Analysis of Money Habitudes

    Delgadillo, Lucy M.; Bushman, Brittani S.


    Use of the Money Habitudes exercise has gained popularity among various financial professionals. This article reports on the reliability of this resource. A survey administered to young adults at a western state university was conducted, and each Habitude or "domain" was analyzed using Cronbach's alpha procedures. Results showed all six…

  17. Inflection points for network reliability

    Brown, J.I.; Koç, Y.; Kooij, R.E.


    Given a finite, undirected graph G (possibly with multiple edges), we assume that the vertices are operational, but the edges are each independently operational with probability p. The (all-terminal) reliability, Rel(G,p), of G is the probability that the spanning subgraph of operational edges is co

  18. Becoming a high reliability organization.

    Christianson, Marlys K; Sutcliffe, Kathleen M; Miller, Melissa A; Iwashyna, Theodore J


    Aircraft carriers, electrical power grids, and wildland firefighting, though seemingly different, are exemplars of high reliability organizations (HROs)--organizations that have the potential for catastrophic failure yet engage in nearly error-free performance. HROs commit to safety at the highest level and adopt a special approach to its pursuit. High reliability organizing has been studied and discussed for some time in other industries and is receiving increasing attention in health care, particularly in high-risk settings like the intensive care unit (ICU). The essence of high reliability organizing is a set of principles that enable organizations to focus attention on emergent problems and to deploy the right set of resources to address those problems. HROs behave in ways that sometimes seem counterintuitive--they do not try to hide failures but rather celebrate them as windows into the health of the system, they seek out problems, they avoid focusing on just one aspect of work and are able to see how all the parts of work fit together, they expect unexpected events and develop the capability to manage them, and they defer decision making to local frontline experts who are empowered to solve problems. Given the complexity of patient care in the ICU, the potential for medical error, and the particular sensitivity of critically ill patients to harm, high reliability organizing principles hold promise for improving ICU patient care.

  19. The investigation of supply chain's reliability measure: a case study

    Taghizadeh, Houshang; Hafezi, Ehsan


    In this paper, using supply chain operational reference, the reliability evaluation of available relationships in supply chain is investigated. For this purpose, in the first step, the chain under investigation is divided into several stages including first and second suppliers, initial and final customers, and the producing company. Based on the formed relationships between these stages, the supply chain system is then broken down into different subsystem parts. The formed relationships between the stages are based on the transportation of the orders between stages. Paying attention to the system elements' location, which can be in one of the five forms of series namely parallel, series/parallel, parallel/series, or their combinations, we determine the structure of relationships in the divided subsystems. According to reliability evaluation scales on the three levels of supply chain, the reliability of each chain is then calculated. Finally, using the formulas of calculating the reliability in combined systems, the reliability of each system and ultimately the whole system is investigated.

  20. Reliability and maintainability analysis of electrical system of drum shearers

    SEYED Hadi Hoseinie; MOHAMMAD Ataei; REZA Khalokakaie; UDAY Kumar


    The reliability and maintainability of electrical system of drum shearer at Parvade.l Coal Mine in central Iran was analyzed. The maintenance and failure data were collected during 19 months of shearer operation. According to trend and serial correlation tests, the data were independent and identically distributed (iid) and therefore the statistical techniques were used for modeling. The data analysis show that the time between failures (TBF) and time to repair (TTR) data obey the lognormal and Weibull 3 parameters distribution respectively. Reliability-based preventive maintenance time intervals for electrical system of the drum shearer were calculated with regard to reliability plot. The reliability-based maintenance intervals for 90%, 80%, 70% and 50% reliability level are respectively 9.91, 17.96, 27.56 and 56.1 h. Also the calculations show that time to repair (TTR) of this system varies in range 0.17-4 h with 1.002 h as mean time to repair (MTTR). There is a 80% chance that the electrical system of shearer of Parvade.l mine repair will be accomplished within 1.45 h.

  1. Reliability for some bivariate gamma distributions

    Nadarajah Saralees


    Full Text Available In the area of stress-strength models, there has been a large amount of work as regards estimation of the reliability R=Pr( Xcalculations involve the use of special functions.

  2. Reliability for some bivariate beta distributions

    Nadarajah Saralees


    Full Text Available In the area of stress-strength models there has been a large amount of work as regards estimation of the reliability R=Pr( Xcalculations involve the use of special functions.

  3. Interval arithmetic in calculations

    Bairbekova, Gaziza; Mazakov, Talgat; Djomartova, Sholpan; Nugmanova, Salima


    Interval arithmetic is the mathematical structure, which for real intervals defines operations analogous to ordinary arithmetic ones. This field of mathematics is also called interval analysis or interval calculations. The given math model is convenient for investigating various applied objects: the quantities, the approximate values of which are known; the quantities obtained during calculations, the values of which are not exact because of rounding errors; random quantities. As a whole, the idea of interval calculations is the use of intervals as basic data objects. In this paper, we considered the definition of interval mathematics, investigated its properties, proved a theorem, and showed the efficiency of the new interval arithmetic. Besides, we briefly reviewed the works devoted to interval analysis and observed basic tendencies of development of integral analysis and interval calculations.

  4. Unit Cost Compendium Calculations

    U.S. Environmental Protection Agency — The Unit Cost Compendium (UCC) Calculations raw data set was designed to provide for greater accuracy and consistency in the use of unit costs across the USEPA...




    This paper presents a procedure for calculating the effective discharge for rivers with alluvial channels.An alluvial river adjusts the bankfull shape and dimensions of its channel to the wide range of flows that mobilize the boundary sediments. It has been shown that time-averaged river morphology is adjusted to the flow that, over a prolonged period, transports most sediment. This is termed the effective discharge.The effective discharge may be calculated provided that the necessary data are available or can be synthesized. The procedure for effective discharge calculation presented here is designed to have general applicability, have the capability to be applied consistently, and represent the effects of physical processes responsible for determining the channel, dimensions. An example of the calculations necessary and applications of the effective discharge concept are presented.

  6. Calculativeness and trust

    Frederiksen, Morten


    Williamson’s characterisation of calculativeness as inimical to trust contradicts most sociological trust research. However, a similar argument is found within trust phenomenology. This paper re-investigates Williamson’s argument from the perspective of Løgstrup’s phenomenological theory of trust....... Contrary to Williamson, however, Løgstrup’s contention is that trust, not calculativeness, is the default attitude and only when suspicion is awoken does trust falter. The paper argues that while Williamson’s distinction between calculativeness and trust is supported by phenomenology, the analysis needs...... to take actual subjective experience into consideration. It points out that, first, Løgstrup places trust alongside calculativeness as a different mode of engaging in social interaction, rather conceiving of trust as a state or the outcome of a decision-making process. Secondly, the analysis must take...

  7. Magnetic Field Grid Calculator

    National Oceanic and Atmospheric Administration, Department of Commerce — The Magnetic Field Properties Calculator will computes the estimated values of Earth's magnetic field(declination, inclination, vertical component, northerly...

  8. Detecting larval export from marine reserves.

    Pelc, R A; Warner, R R; Gaines, S D; Paris, C B


    Marine reserve theory suggests that where large, productive populations are protected within no-take marine reserves, fished areas outside reserves will benefit through the spillover of larvae produced in the reserves. However, empirical evidence for larval export has been sparse. Here we use a simple idealized coastline model to estimate the expected magnitude and spatial scale of larval export from no-take marine reserves across a range of reserve sizes and larval dispersal scales. Results suggest that, given the magnitude of increased production typically found in marine reserves, benefits from larval export are nearly always large enough to offset increased mortality outside marine reserves due to displaced fishing effort. However, the proportional increase in recruitment at sites outside reserves is typically small, particularly for species with long-distance (on the order of hundreds of kilometers) larval dispersal distances, making it very difficult to detect in field studies. Enhanced recruitment due to export may be detected by sampling several sites at an appropriate range of distances from reserves or at sites downcurrent of reserves in systems with directional dispersal. A review of existing empirical evidence confirms the model's suggestion that detecting export may be difficult without an exceptionally large differential in production, short-distance larval dispersal relative to reserve size, directional dispersal, or a sampling scheme that encompasses a broad range of distances from the reserves.

  9. Scientific calculating peripheral

    Ethridge, C.D.; Nickell, J.D. Jr.; Hanna, W.H.


    A scientific calculating peripheral for small intelligent data acquisition and instrumentation systems and for distributed-task processing systems is established with a number-oriented microprocessor controlled by a single component universal peripheral interface microcontroller. A MOS/LSI number-oriented microprocessor provides the scientific calculating capability with Reverse Polish Notation data format. Master processor task definition storage, input data sequencing, computation processing, result reporting, and interface protocol is managed by a single component universal peripheral interface microcontroller.

  10. Current interruption transients calculation

    Peelo, David F


    Provides an original, detailed and practical description of current interruption transients, origins, and the circuits involved, and how they can be calculated Current Interruption Transients Calculationis a comprehensive resource for the understanding, calculation and analysis of the transient recovery voltages (TRVs) and related re-ignition or re-striking transients associated with fault current interruption and the switching of inductive and capacitive load currents in circuits. This book provides an original, detailed and practical description of current interruption transients, origins,

  11. Shielding calculations for SSC

    Van Ginneken, A.


    Monte Carlo calculations of hadron and muon shielding for SSC are reviewed with emphasis on their application to radiation safety and environmental protection. Models and algorithms for simulation of hadronic and electromagnetic showers, and for production and transport of muons in the TeV regime are briefly discussed. Capabilities and limitations of these calculations are described and illustrated with a few examples. 12 refs., 3 figs.

  12. Geometric unsharpness calculations

    Anderson, D.J. [International Training and Education Group (INTEG), Oakville, Ontario (Canada)


    The majority of radiographers' geometric unsharpness calculations are normally performed with a mathematical formula. However, a majority of codes and standards refer to the use of a nomograph for this calculation. Upon first review, the use of a nomograph appears more complicated but with a few minutes of study and practice it can be just as effective. A review of this article should provide enlightenment. (author)

  13. Source and replica calculations

    Whalen, P.P.


    The starting point of the Hiroshima-Nagasaki Dose Reevaluation Program is the energy and directional distributions of the prompt neutron and gamma-ray radiation emitted from the exploding bombs. A brief introduction to the neutron source calculations is presented. The development of our current understanding of the source problem is outlined. It is recommended that adjoint calculations be used to modify source spectra to resolve the neutron discrepancy problem.

  14. INVAP's Nuclear Calculation System

    Ignacio Mochi


    Since its origins in 1976, INVAP has been on continuous development of the calculation system used for design and optimization of nuclear reactors. The calculation codes have been polished and enhanced with new capabilities as they were needed or useful for the new challenges that the market imposed. The actual state of the code packages enables INVAP to design nuclear installations with complex geometries using a set of easy-to-use input files that minimize user errors due to confusion or mi...

  15. Power Quality and Reliability Project

    Attia, John O.


    One area where universities and industry can link is in the area of power systems reliability and quality - key concepts in the commercial, industrial and public sector engineering environments. Prairie View A&M University (PVAMU) has established a collaborative relationship with the University of'Texas at Arlington (UTA), NASA/Johnson Space Center (JSC), and EP&C Engineering and Technology Group (EP&C) a small disadvantage business that specializes in power quality and engineering services. The primary goal of this collaboration is to facilitate the development and implementation of a Strategic Integrated power/Systems Reliability and Curriculum Enhancement Program. The objectives of first phase of this work are: (a) to develop a course in power quality and reliability, (b) to use the campus of Prairie View A&M University as a laboratory for the study of systems reliability and quality issues, (c) to provide students with NASA/EPC shadowing and Internship experience. In this work, a course, titled "Reliability Analysis of Electrical Facilities" was developed and taught for two semesters. About thirty seven has benefited directly from this course. A laboratory accompanying the course was also developed. Four facilities at Prairie View A&M University were surveyed. Some tests that were performed are (i) earth-ground testing, (ii) voltage, amperage and harmonics of various panels in the buildings, (iii) checking the wire sizes to see if they were the right size for the load that they were carrying, (iv) vibration tests to test the status of the engines or chillers and water pumps, (v) infrared testing to the test arcing or misfiring of electrical or mechanical systems.

  16. Three-stage variability-based reserve modifiers for enhancing flexibility reserve requirements under high variable generation penetrations

    Krad, Ibrahim; Gao, David Wenzhong; Ibanez, Eduardo; Ela, Erik


    The electric power system has continuously evolved in order to accommodate new technologies and operating strategies. As the penetration of integrated variable generation in the system increases, it is beneficial to develop strategies that can help mitigate their effect on the grid. Historically, power system operators have held excess capacity during the commitment and dispatch process to allow the system to handle unforeseen load ramping events. As variable generation resources increase, sufficient flexibility scheduled in the system is required to ensure that system performance is not deteriorated in the presence of additional variability and uncertainty. This paper presents a systematic comparison of various flexibility reserve strategies. Several of them are implemented and applied in a common test system, in order to evaluate their effect on the economic and reliable operations. Furthermore, a three stage reserve modifier algorithm is proposed and evaluated for its ability to improve system performance.

  17. Reliability Analysis for Tunnel Supports System by Using Finite Element Method

    E. Bukaçi


    Full Text Available Reliability analysis is a method that can be used in almost any geotechnical engineering problem. Using this method requires the knowledge of parameter uncertainties, which can be expressed by their standard deviation value. By performing reliability analysis to tunnel supports design, can be obtained a range of safety factors and by using them, probability of failure can be calculated. Problem becomes more complex when this analysis is performed for numerical methods, such as Finite Element Method. This paper gives a solution to how reliability analysis can be performed to design tunnel supports, by using Point Estimate Method to calculate reliability index. As a case study, is chosen one of the energy tunnels at Fan Hydropower plant, in Rrëshen Albania. As results, values of factor of safety and probability of failure are calculated. Also some suggestions using reliability analysis with numerical methods are given.

  18. Reserve Growth of Alberta Oil Pools

    Verma, Mahendra K.; Cook, Troy


    This Open-File Report is based on a presentation delivered at the Fourth U.S. Geological Survey Workshop on Reserve Growth on March 10-11, 2008. It summarizes the results of a study of reserve growth of oil pools in Alberta Province, Canada. The study is part of a larger effort involving similar studies of fields in other important petroleum provinces around the world, with the overall objective of gaining a better understanding of reserve growth in fields with different geologic/reservoir parameters and different operating environments. The goals of the study were to: 1. Evaluate historical oil reserve data and assess reserve growth. 2. Develop reserve growth models/functions to help forecast hydrocarbon volumes. 3. Study reserve growth sensitivity to various parameters ? for example, pool size, porosity, oil gravity, and lithology. 4. Compare reserve growth in oil pools/fields of Alberta provinces with those from other large petroleum provinces.

  19. Marine reserve effects on fishery profit.

    White, Crow; Kendall, Bruce E; Gaines, Steven; Siegel, David A; Costello, Christopher


    Some studies suggest that fishery yields can be higher with reserves than under conventional management. However, the economic performance of fisheries depends on economic profit, not fish yield. The predictions of higher yields with reserves rely on intensive fishing pressures between reserves; the exorbitant costs of harvesting low-density populations erode profits. We incorporated this effect into a bioeconomic model to evaluate the economic performance of reserve-based management. Our results indicate that reserves can still benefit fisheries, even those targeting species that are expensive to harvest. However, in contrast to studies focused on yield, only a moderate proportion of the coast in reserves (with moderate harvest pressures outside reserves) is required to maximize profit. Furthermore, reserve area and harvest intensity can be traded off with little impact on profits, allowing for management flexibility while still providing higher profit than attainable under conventional management.

  20. Reserving by detailed conditioning on individual claim

    Kartikasari, Mujiati Dwi; Effendie, Adhitya Ronnie; Wilandari, Yuciana


    The estimation of claim reserves is an important activity in insurance companies to fulfill their liabilities. Recently, reserving method of individual claim have attracted a lot of interest in the actuarial science, which overcome some deficiency of aggregated claim method. This paper explores the Reserving by Detailed Conditioning (RDC) method using all of claim information for reserving with individual claim of liability insurance from an Indonesian general insurance company. Furthermore, we compare it to Chain Ladder and Bornhuetter-Ferguson method.

  1. Mordovia State Nature Reserve's 80th anniversary

    Elena V. Vargot


    Brief physical-geographical characteristics, history of creation and development of the Mordovia State Nature Reserve territory are presented. We listed aims and objectives assigned for the Mordovia Reserve in different periods. During the first years of the Mordovia Reserve the forest conservation was aimed at reforestation of the southern area of the taiga zone; the investigation of harmful insect fauna to timely response on infection foci of trees; enriching of the fauna of the Reserve. At...

  2. Study on Storage Reliability Evaluation for Ammunition Using Gibbs Sampler


    For the gradual maturity of Bayesian survival analysis theory, as well as the defects of the traditional methods for storage reliability evaluation, the Bayesian survival analysis method is proposed to build regression models for reliability in the random truncated test. These models can reflect the influences of different environments on the ammunition storage lifetime. As an example, the common exponential distribution is used here, and Markov chain Monte Carlo(MCMC)method based on Gibbs sampling dynamically simulates the Markov chain of the parameters' posterior distribution. Also,the parameters' Bayesian estimations are calculated in the random truncated condition. The simulation results show that the proposed method is effective and directly perceived.

  3. Structural Reliability of Plain Bearings for Wave Energy Converter Applications

    Ambühl, Simon; Kramer, Morten Mejlhede; Sørensen, John Dalsgaard


    The levelized cost of energy (LCOE) from wave energy converters (WECs) needs to be decreased in order to be able to become competitive with other renewable electricity sources. Probabilistic reliability methods can be used to optimize the structure of WECs. Optimization is often performed...... the hydraulic cycle when waves are passing. The new PTO system leads to different load characteristics at the floater itself compared to the actual setup where the turbine/generator is directly coupled to the fluctuating hydraulic pressure within the PTO system. This paper calculates the structural reliability...

  4. Final Report for the Virtual Reliability Realization System LDRD



    Current approaches to reliability are not adequate to keep pace with the need for faster, better and cheaper products and systems. This is especially true in high consequence of failure applications. The original proposal for the LDRD was to look at this challenge and see if there was a new paradigm that could make reliability predictions, along with a quantitative estimate of the risk in that prediction, in a way that was faster, better and cheaper. Such an approach would be based on the underlying science models that are the backbone of reliability predictions. The new paradigm would be implemented in two software tools: the Virtual Reliability Realization System (VRRS) and the Reliability Expert System (REX). The three-year LDRD was funded at a reduced level for the first year ($120K vs. $250K) and not renewed. Because of the reduced funding, we concentrated on the initial development of the expertise system. We developed an interactive semiconductor calculation tool needed for reliability analyses. We also were able to generate a basic functional system using Microsoft Siteserver Commerce Edition and Microsoft Sequel Server. The base system has the capability to store Office documents from multiple authors, and has the ability to track and charge for usage. The full outline of the knowledge model has been incorporated as well as examples of various types of content.

  5. Multi-mode reliability-based design of horizontal curves.

    Essa, Mohamed; Sayed, Tarek; Hussein, Mohamed


    Recently, reliability analysis has been advocated as an effective approach to account for uncertainty in the geometric design process and to evaluate the risk associated with a particular design. In this approach, a risk measure (e.g. probability of noncompliance) is calculated to represent the probability that a specific design would not meet standard requirements. The majority of previous applications of reliability analysis in geometric design focused on evaluating the probability of noncompliance for only one mode of noncompliance such as insufficient sight distance. However, in many design situations, more than one mode of noncompliance may be present (e.g. insufficient sight distance and vehicle skidding at horizontal curves). In these situations, utilizing a multi-mode reliability approach that considers more than one failure (noncompliance) mode is required. The main objective of this paper is to demonstrate the application of multi-mode (system) reliability analysis to the design of horizontal curves. The process is demonstrated by a case study of Sea-to-Sky Highway located between Vancouver and Whistler, in southern British Columbia, Canada. Two noncompliance modes were considered: insufficient sight distance and vehicle skidding. The results show the importance of accounting for several noncompliance modes in the reliability model. The system reliability concept could be used in future studies to calibrate the design of various design elements in order to achieve consistent safety levels based on all possible modes of noncompliance.

  6. Reliability of the Function in Sitting Test (FIST

    Sharon L. Gorman


    Full Text Available The function in sitting test (FIST is a newly developed, performance-based measure examining deficits in seated postural control. The FIST has been shown to be internally consistent and valid in persons with neurological dysfunction but intra- and interrater reliability and test-retest reliability have not been previously described. Seven patients with chronic neurologic dysfunction were tested and videotaped performing the FIST on two consecutive days. Seventeen acute care and inpatient rehabilitation physical therapist raters scored six of the videotaped performance of the FIST on two occasions at least 2 weeks apart. Intraclass correlation coefficients were used to calculate the test-retest and intra- and interrater reliability of the FIST. ICC of 0.97 (95% CI 0.847–0.995 indicated excellent test-retest reliability of the FIST. Intra- and interrater reliability was also excellent with ICCs of 0.99 (95% CI 0.994–0.997 and 0.99 (95% CI 0.988–0.994, respectively. Physical therapists and other rehabilitation professionals can confidently use the FIST in a variety of clinical practice and research settings due to its favorable reliability characteristics. More studies are needed to describe the responsiveness and minimal clinically important level of change in FIST scores to further enhance clinical usefulness of this measure.

  7. 40 CFR 35.2020 - Reserves.


    ... under § 35.2025. The Regional Administrator may waive this reserve requirement where a State can... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Reserves. 35.2020 Section 35.2020... ASSISTANCE Grants for Construction of Treatment Works § 35.2020 Reserves. In developing its priority list the...

  8. Poverty and corruption compromise tropical forest reserves.

    Wright, S Joseph; Sanchez-Azofeifa, G Arturo; Portillo-Quintero, Carlos; Davies, Diane


    We used the global fire detection record provided by the satellite-based Moderate Resolution Imaging Spectroradiometer (MODIS) to determine the number of fires detected inside 823 tropical and subtropical moist forest reserves and for contiguous buffer areas 5, 10, and 15 km wide. The ratio of fire detection densities (detections per square kilometer) inside reserves to their contiguous buffer areas provided an index of reserve effectiveness. Fire detection density was significantly lower inside reserves than in paired, contiguous buffer areas but varied by five orders of magnitude among reserves. The buffer: reserve detection ratio varied by up to four orders of magnitude among reserves within a single country, and median values varied by three orders of magnitude among countries. Reserves tended to be least effective at reducing fire frequency in many poorer countries and in countries beset by corruption. Countries with the most successful reserves include Costa Rica, Jamaica, Malaysia, and Taiwan and the Indonesian island of Java. Countries with the most problematic reserves include Cambodia, Guatemala, Paraguay, and Sierra Leone and the Indonesian portion of Borneo. We provide fire detection density for 3964 tropical and subtropical reserves and their buffer areas in the hope that these data will expedite further analyses that might lead to improved management of tropical reserves.

  9. Micro-level stochastic loss reserving

    Antonio, K.; Plat, R.


    To meet future liabilities general insurance companies will set-up reserves. Predicting future cash-flows is essential in this process. Actuarial loss reserving methods will help them to do this in a sound way. The last decennium a vast literature about stochastic loss reserving for the general insu

  10. 42 CFR 417.934 - Reserve requirement.


    ... 42 Public Health 3 2010-10-01 2010-10-01 false Reserve requirement. 417.934 Section 417.934 Public... PLANS Administration of Outstanding Loans and Loan Guarantees § 417.934 Reserve requirement. (a) Timing... section 1305 of the PHS Act was required to establish a restricted reserve account on the earlier of...

  11. Reserve Requirements and Monetary Management; An Introduction

    International Monetary Fund


    Reserve requirements are widely used by central banks as a means to improve monetary control, an instrument for policy implementation, a source of revenue, and a safeguard of bank liquidity. The effectiveness of reserve requirements in fulfilling these functions is reviewed, and the detailed modalities of their use are examined. Reserve requirements in a sample of developing countries are described.

  12. 5 CFR 890.503 - Reserves.


    ... any, of the contingency reserve over the preferred minimum balance. OMP must authorize this payment... charge consists of the rate approved by OPM for payment to the plan for each enrollee, plus 4 percent, of... charge set aside for the administrative reserve. The administrative reserve is available for payment of...

  13. 40 CFR 35.2123 - Reserve capacity.


    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Reserve capacity. 35.2123 Section 35... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works § 35.2123 Reserve capacity. EPA will limit grant assistance for reserve capacity as follows: (a) If EPA awarded a grant for a Step...

  14. Army Reserve (AR) Educational Assistance (EA) Study


    NAME(S) AND ADDRESS(ES) US Army TRADOC Analysis Center Ft. Lee, VA 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/ MONITORING AGENCY NAME(S...Programs REAP: Reserve Education Assistance Program; MGIB-SR: Montgomery GI Bill – Selected Reserve; SRK: Selected Reserve Kicker ; OFF: Officer; EM

  15. Reserve Requirements and Monetary Management; An Introduction

    International Monetary Fund


    Reserve requirements are widely used by central banks as a means to improve monetary control, an instrument for policy implementation, a source of revenue, and a safeguard of bank liquidity. The effectiveness of reserve requirements in fulfilling these functions is reviewed, and the detailed modalities of their use are examined. Reserve requirements in a sample of developing countries are described.

  16. Long-term reliability of the visual EEG Poffenberger paradigm.

    Friedrich, Patrick; Ocklenburg, Sebastian; Mochalski, Lisa; Schlüter, Caroline; Güntürkün, Onur; Genc, Erhan


    The Poffenberger paradigm is a simple perception task that is used to estimate the speed of information transfer between the two hemispheres, the so-called interhemispheric transfer time (IHTT). Although the original paradigm is a behavioral task, it can be combined with electroencephalography (EEG) to assess the underlying neurophysiological processes during task execution. While older studies have supported the validity of both paradigms for investigating interhemispheric interactions, their long-term reliability has not been assessed systematically before. The present study aims to fill this gap by determining both internal consistency and long-term test-retest reliability of IHTTs produced by using the two different versions of the Poffenberger paradigm in a sample of 26 healthy subjects. The results show high reliability for the EEG Poffenberger paradigm. In contrast, reliability measures for the behavioral Poffenberger paradigm were low. Hence, our results indicate that electrophysiological measures of interhemispheric transfer are more reliable than behavioral measures; the later should be used with caution in research investigating inter-individual differences of neurocognitive measures. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Robust Reliability or reliable robustness? - Integrated consideration of robustness and reliability aspects

    Kemmler, S.; Eifler, Tobias; Bertsche, B.


    products are and vice versa. For a comprehensive understanding and to use existing synergies between both domains, this paper discusses the basic principles of Reliability- and Robust Design theory. The development of a comprehensive model will enable an integrated consideration of both domains...

  18. Calculations in apheresis.

    Neyrinck, Marleen M; Vrielink, Hans


    It's important to work smoothly with your apheresis equipment when you are an apheresis nurse. Attention should be paid to your donor/patient and the product you're collecting. It gives additional value to your work when you are able to calculate the efficiency of your procedures. You must be capable to obtain an optimal product without putting your donor/patient at risk. Not only the total blood volume (TBV) of the donor/patient plays an important role, but also specific blood values influence the apheresis procedure. Therefore, not all donors/patients should be addressed in the same way. Calculation of TBV, extracorporeal volume, and total plasma volume is needed. Many issues determine your procedure time. By knowing the collection efficiency (CE) of your apheresis machine, you can calculate the number of blood volumes to be processed to obtain specific results. You can calculate whether you need one procedure to obtain specific results or more. It's not always needed to process 3× the TBV. In this way, it can be avoided that the donor/patient is needless long connected to the apheresis device. By calculating the CE of each device, you can also compare the various devices for quality control reasons, but also nurses/operators.

  19. 78 FR 30804 - Transmission Planning Reliability Standards


    ... proposed Reliability Standard TPL-001-2, submitted by the North American Electric Reliability Corporation... American Electric Reliability Corporation (NERC), the Commission-certified Electric Reliability... Microsoft Word format for viewing, printing, and/or downloading. To access this document in eLibrary,...

  20. Reliability and validity of television food advertising questionnaire in Malaysia.

    Zalma, Abdul Razak; Safiah, Md Yusof; Ajau, Danis; Khairil Anuar, Md Isa


    Interventions to counter the influence of television food advertising amongst children are important. Thus, reliable and valid instrument to assess its effect is needed. The objective of this study was to determine the reliability and validity of such a questionnaire. The questionnaire was administered twice on 32 primary schoolchildren aged 10-11 years in Selangor, Malaysia. The interval between the first and second administration was 2 weeks. Test-retest method was used to examine the reliability of the questionnaire. Intra-rater reliability was determined by kappa coefficient and internal consistency by Cronbach's alpha coefficient. Construct validity was evaluated using factor analysis. The test-retest correlation showed moderate-to-high reliability for all scores (r = 0.40*, p = 0.02 to r = 0.95**, p = 0.00), with one exception, consumption of fast foods (r = 0.24, p = 0.20). Kappa coefficient showed acceptable-to-strong intra-rater reliability (K = 0.40-0.92), except for two items under knowledge on television food advertising (K = 0.26 and K = 0.21) and one item under preference for healthier foods (K = 0.33). Cronbach's alpha coefficient indicated acceptable internal consistency for all scores (0.45-0.60). After deleting two items under Consumption of Commonly Advertised Food, the items showed moderate-to-high loading (0.52, 0.84, 0.42 and 0.42) with the Scree plot showing that there was only one factor. The Kaiser-Meyer-Olkin was 0.60, showing that the sample was adequate for factor analysis. The questionnaire on television food advertising is reliable and valid to assess the effect of media literacy education on television food advertising on schoolchildren. © The Author (2013). Published by Oxford University Press. All rights reserved. For Permissions, please email: