Reliability analysis of multicellular system architectures for low-cost satellites

Science.gov (United States)

Erlank, A. O.; Bridges, C. P.

2018-06-01

Multicellular system architectures are proposed as a solution to the problem of low reliability currently seen amongst small, low cost satellites. In a multicellular architecture, a set of independent k-out-of-n systems mimic the cells of a biological organism. In order to be beneficial, a multicellular architecture must provide more reliability per unit of overhead than traditional forms of redundancy. The overheads include power consumption, volume and mass. This paper describes the derivation of an analytical model for predicting a multicellular system's lifetime. The performance of such architectures is compared against that of several common forms of redundancy and proven to be beneficial under certain circumstances. In addition, the problem of peripheral interfaces and cross-strapping is investigated using a purpose-developed, multicellular simulation environment. Finally, two case studies are presented based on a prototype cell implementation, which demonstrate the feasibility of the proposed architecture.

18 CFR 39.4 - Funding of the Electric Reliability Organization.

Science.gov (United States)

2010-04-01

... CERTIFICATION OF THE ELECTRIC RELIABILITY ORGANIZATION; AND PROCEDURES FOR THE ESTABLISHMENT, APPROVAL, AND ENFORCEMENT OF ELECTRIC RELIABILITY STANDARDS § 39.4 Funding of the Electric Reliability Organization. (a) Any... Reliability Organization. 39.4 Section 39.4 Conservation of Power and Water Resources FEDERAL ENERGY...

Reliability-cost models for the power switching devices of wind power converters

DEFF Research Database (Denmark)

Ma, Ke; Blaabjerg, Frede

2012-01-01

In order to satisfy the growing reliability requirements for the wind power converters with more cost-effective solution, the target of this paper is to establish a new reliability-cost model which can connect the relationship between reliability performances and corresponding semiconductor cost...... temperature mean value Tm and fluctuation amplitude ΔTj of power devices, are presented. With the proposed reliability-cost model, it is possible to enable future reliability-oriented design of the power switching devices for wind power converters, and also an evaluation benchmark for different wind power...... for power switching devices. First the conduction loss, switching loss as well as thermal impedance models of power switching devices (IGBT module) are related to the semiconductor chip number information respectively. Afterwards simplified analytical solutions, which can directly extract the junction...

When and why are reliable organizations favored?

DEFF Research Database (Denmark)

Ethiraj, Sendil; Yi, Sangyoon

of the ensuing work examined only corollary implications of this observation. We treat the observation as a research question and ask: when and why are reliable organizations favored by evolutionary forces? Using a simple theoretical model, we direct attention at a minimal set of variables that are implicated...... shocks, reliable organizations can in fact outperform their less reliable counterparts if they can take advantage of the knowledge resident in their historical choices. While these results are counter-intuitive, the caveat is that our results are only an existence proof for our theory rather than...

Comprehensive low-cost reliability centered maintenance. Final report

International Nuclear Information System (INIS)

Rotton, S.J.; Dozier, I.J.; Thow, R.

1995-09-01

Reliability Centered Maintenance (RCM) is a maintenance optimization approach that all electric utilities can apply to power plant systems. The Electric Power Research Institute and PECO Energy Company jointly sponsored this Comprehensive Low-Cost Reliability Centered Maintenance project to demonstrate that the standard RCM methodology could be streamlined to reduce the cost of analysis while maintaining a high quality product. EPRI's previous investigation of streamlined RCM methods being pioneered in the nuclear industry indicated that PECO Energy could expect to optimize its maintenance program at reduced cost by carefully controlling the scope without sacrificing documentation or technical quality. Using the insights obtained from these previous studies, three methods were defined in this project and were demonstrated in a large scale application to 60 systems at both the Limerick Generating Station and the Peach Bottom Atomic Power Station

Novel Low Cost, High Reliability Wind Turbine Drivetrain

Energy Technology Data Exchange (ETDEWEB)

Chobot, Anthony; Das, Debarshi; Mayer, Tyler; Markey, Zach; Martinson, Tim; Reeve, Hayden; Attridge, Paul; El-Wardany, Tahany

2012-09-13

Clipper Windpower, in collaboration with United Technologies Research Center, the National Renewable Energy Laboratory, and Hamilton Sundstrand Corporation, developed a low-cost, deflection-compliant, reliable, and serviceable chain drive speed increaser. This chain and sprocket drivetrain design offers significant breakthroughs in the areas of cost and serviceability and addresses the key challenges of current geared and direct-drive systems. The use of gearboxes has proven to be challenging; the large torques and bending loads associated with use in large multi-MW wind applications have generally limited demonstrated lifetime to 8-10 years [1]. The large cost of gearbox replacement and the required use of large, expensive cranes can result in gearbox replacement costs on the order of $1M, representing a significant impact to overall cost of energy (COE). Direct-drive machines eliminate the gearbox, thereby targeting increased reliability and reduced life-cycle cost. However, the slow rotational speeds require very large and costly generators, which also typically have an undesirable dependence on expensive rare-earth magnet materials and large structural penalties for precise air gap control. The cost of rare-earth materials has increased 20X in the last 8 years representing a key risk to ever realizing the promised cost of energy reductions from direct-drive generators. A common challenge to both geared and direct drive architectures is a limited ability to manage input shaft deflections. The proposed Clipper drivetrain is deflection-compliant, insulating later drivetrain stages and generators from off-axis loads. The system is modular, allowing for all key parts to be removed and replaced without the use of a high capacity crane. Finally, the technology modularity allows for scalability and many possible drivetrain topologies. These benefits enable reductions in drivetrain capital cost by 10.0%, levelized replacement and O&M costs by 26.7%, and overall cost of

The relationship between cost estimates reliability and BIM adoption: SEM analysis

Science.gov (United States)

Ismail, N. A. A.; Idris, N. H.; Ramli, H.; Rooshdi, R. R. Raja Muhammad; Sahamir, S. R.

2018-02-01

This paper presents the usage of Structural Equation Modelling (SEM) approach in analysing the effects of Building Information Modelling (BIM) technology adoption in improving the reliability of cost estimates. Based on the questionnaire survey results, SEM analysis using SPSS-AMOS application examined the relationships between BIM-improved information and cost estimates reliability factors, leading to BIM technology adoption. Six hypotheses were established prior to SEM analysis employing two types of SEM models, namely the Confirmatory Factor Analysis (CFA) model and full structural model. The SEM models were then validated through the assessment on their uni-dimensionality, validity, reliability, and fitness index, in line with the hypotheses tested. The final SEM model fit measures are: P-value=0.000, RMSEA=0.0790.90, TLI=0.956>0.90, NFI=0.935>0.90 and ChiSq/df=2.259; indicating that the overall index values achieved the required level of model fitness. The model supports all the hypotheses evaluated, confirming that all relationship exists amongst the constructs are positive and significant. Ultimately, the analysis verified that most of the respondents foresee better understanding of project input information through BIM visualization, its reliable database and coordinated data, in developing more reliable cost estimates. They also perceive to accelerate their cost estimating task through BIM adoption.

Derating design for optimizing reliability and cost with an application to liquid rocket engines

International Nuclear Information System (INIS)

Kim, Kyungmee O.; Roh, Taeseong; Lee, Jae-Woo; Zuo, Ming J.

2016-01-01

Derating is the operation of an item at a stress that is lower than its rated design value. Previous research has indicated that reliability can be increased from operational derating. In order to derate an item in field operation, however, an engineer must rate the design of the item at a stress level higher than the operational stress level, which increases the item's nominal failure rate and development costs. At present, there is no model available to quantify the cost and reliability that considers the design uprating as well as the operational derating. In this paper, we establish the reliability expression in terms of the derating level assuming that the nominal failure rate is constant with time for a fixed rated design value. The total development cost is expressed in terms of the rated design value and the number of tests necessary to demonstrate the reliability requirement. The properties of the optimal derating level are explained for maximizing the reliability or for minimizing the cost. As an example, the proposed model is applied to the design of liquid rocket engines. - Highlights: • Modeled the effect of derating design on the reliability and the development cost. • Discovered that derating design may reduce the cost of reliability demonstration test. • Optimized the derating design parameter for reliability maximization or cost minimization.

Wind turbine reliability :understanding and minimizing wind turbine operation and maintenance costs.

Energy Technology Data Exchange (ETDEWEB)

Walford, Christopher A. (Global Energy Concepts. Kirkland, WA)

2006-03-01

Wind turbine system reliability is a critical factor in the success of a wind energy project. Poor reliability directly affects both the project's revenue stream through increased operation and maintenance (O&M) costs and reduced availability to generate power due to turbine downtime. Indirectly, the acceptance of wind-generated power by the financial and developer communities as a viable enterprise is influenced by the risk associated with the capital equipment reliability; increased risk, or at least the perception of increased risk, is generally accompanied by increased financing fees or interest rates. This paper outlines the issues relevant to wind turbine reliability for wind turbine power generation projects. The first sections describe the current state of the industry, identify the cost elements associated with wind farm O&M and availability and discuss the causes of uncertainty in estimating wind turbine component reliability. The latter sections discuss the means for reducing O&M costs and propose O&M related research and development efforts that could be pursued by the wind energy research community to reduce cost of energy.

Reliability theory for repair service organization simulation and increase of innovative attraction of industrial enterprises

Science.gov (United States)

Dolzhenkova, E. V.; Iurieva, L. V.

2018-05-01

The study presents the author's algorithm for the industrial enterprise repair service organization simulation based on the reliability theory, as well as the results of its application. The monitoring of the industrial enterprise repair service organization is proposed to perform on the basis of the enterprise's state indexes for the main resources (equipment, labour, finances, repair areas), which allows quantitative evaluation of the reliability level as a resulting summary rating of the said parameters and the ensuring of an appropriate level of the operation reliability of the serviced technical objects. Under the conditions of the tough competition, the following approach is advisable: the higher efficiency of production and a repair service itself, the higher the innovative attractiveness of an industrial enterprise. The results of the calculations show that in order to prevent inefficient losses of production and to reduce the repair costs, it is advisable to apply the reliability theory. The overall reliability rating calculated on the basis of the author's algorithm has low values. The processing of the statistical data forms the reliability characteristics for the different workshops and services of an industrial enterprise, which allows one to define the failure rates of the various units of equipment and to establish the reliability indexes necessary for the subsequent mathematical simulation. The proposed simulating algorithm contributes to an increase of the efficiency of the repair service organization and improvement of the innovative attraction of an industrial enterprise.

Using a Hybrid Cost-FMEA Analysis for Wind Turbine Reliability Analysis

Directory of Open Access Journals (Sweden)

Nacef Tazi

2017-02-01

Full Text Available Failure mode and effects analysis (FMEA has been proven to be an effective methodology to improve system design reliability. However, the standard approach reveals some weaknesses when applied to wind turbine systems. The conventional criticality assessment method has been criticized as having many limitations such as the weighting of severity and detection factors. In this paper, we aim to overcome these drawbacks and develop a hybrid cost-FMEA by integrating cost factors to assess the criticality, these costs vary from replacement costs to expected failure costs. Then, a quantitative comparative study is carried out to point out average failure rate, main cause of failure, expected failure costs and failure detection techniques. A special reliability analysis of gearbox and rotor-blades are presented.

Transmission embedded cost allocation methodology with consideration of system reliability

International Nuclear Information System (INIS)

Hur, D.; Park, J.-K.; Yoo, C.-I.; Kim, B.H.

2004-01-01

In a vertically integrated utility industry, the cost of reliability, as a separate service, has not received much rigorous analysis. However, as a cornerstone of restructuring the industry, the transmission service pricing must change to be consistent with, and supportive of, competitive wholesale electricity markets. This paper focuses on the equitable allocation of transmission network embedded costs including the transmission reliability cost based on the contributions of each generator to branch flows under normal conditions as well as the line outage impact factor under a variety of load levels. A numerical example on a six-bus system is given to illustrate the applications of the proposed methodology. (author)

Application of SAW method for multiple-criteria comparative analysis of the reliability of heat supply organizations

Science.gov (United States)

Akhmetova, I. G.; Chichirova, N. D.

2016-12-01

Heat supply is the most energy-consuming sector of the economy. Approximately 30% of all used primary fuel-and-energy resources is spent on municipal heat-supply needs. One of the key indicators of activity of heat-supply organizations is the reliability of an energy facility. The reliability index of a heat supply organization is of interest to potential investors for assessing risks when investing in projects. The reliability indices established by the federal legislation are actually reduced to a single numerical factor, which depends on the number of heat-supply outages in connection with disturbances in operation of heat networks and the volume of their resource recovery in the calculation year. This factor is rather subjective and may change in a wide range during several years. A technique is proposed for evaluating the reliability of heat-supply organizations with the use of the simple additive weighting (SAW) method. The technique for integrated-index determination satisfies the following conditions: the reliability level of the evaluated heat-supply system is represented maximum fully and objectively; the information used for the reliability-index evaluation is easily available (is located on the Internet in accordance with demands of data-disclosure standards). For reliability estimation of heat-supply organizations, the following indicators were selected: the wear of equipment of thermal energy sources, the wear of heat networks, the number of outages of supply of thermal energy (heat carrier due to technological disturbances on heat networks per 1 km of heat networks), the number of outages of supply of thermal energy (heat carrier due to technologic disturbances on thermal energy sources per 1 Gcal/h of installed power), the share of expenditures in the cost of thermal energy aimed at recovery of the resource (renewal of fixed assets), coefficient of renewal of fixed assets, and a coefficient of fixed asset retirement. A versatile program is developed

Revenue Sufficiency and Reliability in a Zero Marginal Cost Future

Energy Technology Data Exchange (ETDEWEB)

Frew, Bethany A.

2017-04-17

Features of existing wholesale electricity markets, such as administrative pricing rules and policy-based reliability standards, can distort market incentives from allowing generators sufficient opportunities to recover both fixed and variable costs. Moreover, these challenges can be amplified by other factors, including (1) inelastic demand resulting from a lack of price signal clarity, (2) low- or near-zero marginal cost generation, particularly arising from low natural gas fuel prices and variable generation (VG), such as wind and solar, and (3) the variability and uncertainty of this VG. As power systems begin to incorporate higher shares of VG, many questions arise about the suitability of the existing marginal-cost-based price formation, primarily within an energy-only market structure, to ensure the economic viability of resources that might be needed to provide system reliability. This article discusses these questions and provides a summary of completed and ongoing modelling-based work at the National Renewable Energy Laboratory to better understand the impacts of evolving power systems on reliability and revenue sufficiency.

Alternative ceramic circuit constructions for low cost, high reliability applications

International Nuclear Information System (INIS)

Modes, Ch.; O'Neil, M.

1997-01-01

The growth in the use of hybrid circuit technology has recently been challenged by recent advances in low cost laminate technology, as well as the continued integration of functions into IC's. Size reduction of hybrid 'packages' has turned out to be a means to extend the useful life of this technology. The suppliers of thick film materials technology have responded to this challenge by developing a number of technology options to reduce circuit size, increase density, and reduce overall cost, while maintaining or increasing reliability. This paper provides an overview of the processes that have been developed, and, in many cases are used widely to produce low cost, reliable microcircuits. Comparisons of each of these circuit fabrication processes are made with a discussion of advantages and disadvantages of each technology. (author)

Parts and Components Reliability Assessment: A Cost Effective Approach

Science.gov (United States)

Lee, Lydia

2009-01-01

System reliability assessment is a methodology which incorporates reliability analyses performed at parts and components level such as Reliability Prediction, Failure Modes and Effects Analysis (FMEA) and Fault Tree Analysis (FTA) to assess risks, perform design tradeoffs, and therefore, to ensure effective productivity and/or mission success. The system reliability is used to optimize the product design to accommodate today?s mandated budget, manpower, and schedule constraints. Stand ard based reliability assessment is an effective approach consisting of reliability predictions together with other reliability analyses for electronic, electrical, and electro-mechanical (EEE) complex parts and components of large systems based on failure rate estimates published by the United States (U.S.) military or commercial standards and handbooks. Many of these standards are globally accepted and recognized. The reliability assessment is especially useful during the initial stages when the system design is still in the development and hard failure data is not yet available or manufacturers are not contractually obliged by their customers to publish the reliability estimates/predictions for their parts and components. This paper presents a methodology to assess system reliability using parts and components reliability estimates to ensure effective productivity and/or mission success in an efficient manner, low cost, and tight schedule.

Least-cost failure diagnosis in uncertain reliability systems

International Nuclear Information System (INIS)

Cox, Louis Anthony; Chiu, Steve Y.; Sun Xiaorong

1996-01-01

In many textbook solutions, for systems failure diagnosis problems studied using reliability theory and artificial intelligence, the prior probabilities of different failure states can be estimated and used to guide the sequential search for failed components after the whole system fails. In practice, however, both the component failure probabilities and the structure function of the system being examined--i.e., the mapping between the states of its components and the state of the system--may not be known with certainty. At best:, the probabilities of different hypothesized system descriptions, each specifying the component failure probabilities and the system's structure function, may be known to a useful approximation, perhaps based on sample data and previous experience. Cost-effective diagnosis of the system's failure state is then a challenging problem. Although the probabilities of component failures are aleatory, uncertainties about these probabilities and about the system structure function are epistemic. This paper examines how to make best use of both epistemic prior probabilities for system descriptions and the information gleaned from costly inspections of component states after the system fails, to minimize the average cost of identifying the failure state. Two approaches are introduced for systems dominated by aleatory uncertainties, one motivated by information theory and the other based on the idea of trying to prove a hypothesis about the identity of the failure state as efficiently as possible. While the general problem of cost-effective failure diagnosis is computationally intractable (NP-hard), both heuristics provide useful approximations on small to moderate sized problems and optimal results for certain common types of reliability systems, including series, parallel, parallel-series, and k-out-of-n systems. A hybrid heuristic that adaptively chooses which heuristic to apply next after any sequence of observations (component test results

Standard semiconductor packaging for high-reliability low-cost MEMS applications

Science.gov (United States)

Harney, Kieran P.

2005-01-01

Microelectronic packaging technology has evolved over the years in response to the needs of IC technology. The fundamental purpose of the package is to provide protection for the silicon chip and to provide electrical connection to the circuit board. Major change has been witnessed in packaging and today wafer level packaging technology has further revolutionized the industry. MEMS (Micro Electro Mechanical Systems) technology has created new challenges for packaging that do not exist in standard ICs. However, the fundamental objective of MEMS packaging is the same as traditional ICs, the low cost and reliable presentation of the MEMS chip to the next level interconnect. Inertial MEMS is one of the best examples of the successful commercialization of MEMS technology. The adoption of MEMS accelerometers for automotive airbag applications has created a high volume market that demands the highest reliability at low cost. The suppliers to these markets have responded by exploiting standard semiconductor packaging infrastructures. However, there are special packaging needs for MEMS that cannot be ignored. New applications for inertial MEMS devices are emerging in the consumer space that adds the imperative of small size to the need for reliability and low cost. These trends are not unique to MEMS accelerometers. For any MEMS technology to be successful the packaging must provide the basic reliability and interconnection functions, adding the least possible cost to the product. This paper will discuss the evolution of MEMS packaging in the accelerometer industry and identify the main issues that needed to be addressed to enable the successful commercialization of the technology in the automotive and consumer markets.

Designing the optimal bit: balancing energetic cost, speed and reliability.

Science.gov (United States)

Deshpande, Abhishek; Gopalkrishnan, Manoj; Ouldridge, Thomas E; Jones, Nick S

2017-08-01

We consider the challenge of operating a reliable bit that can be rapidly erased. We find that both erasing and reliability times are non-monotonic in the underlying friction, leading to a trade-off between erasing speed and bit reliability. Fast erasure is possible at the expense of low reliability at moderate friction, and high reliability comes at the expense of slow erasure in the underdamped and overdamped limits. Within a given class of bit parameters and control strategies, we define 'optimal' designs of bits that meet the desired reliability and erasing time requirements with the lowest operational work cost. We find that optimal designs always saturate the bound on the erasing time requirement, but can exceed the required reliability time if critically damped. The non-trivial geometry of the reliability and erasing time scales allows us to exclude large regions of parameter space as suboptimal. We find that optimal designs are either critically damped or close to critical damping under the erasing procedure.

Revenue Sufficiency and Reliability in a Zero Marginal Cost Future: Preprint

Energy Technology Data Exchange (ETDEWEB)

Frew, Bethany A.; Milligan, Michael; Brinkman, Greg; Bloom, Aaron; Clark, Kara; Denholm, Paul

2016-12-01

Features of existing wholesale electricity markets, such as administrative pricing rules and policy-based reliability standards, can distort market incentives from allowing generators sufficient opportunities to recover both fixed and variable costs. Moreover, these challenges can be amplified by other factors, including (1) inelastic demand resulting from a lack of price signal clarity, (2) low- or near-zero marginal cost generation, particularly arising from low natural gas fuel prices and variable generation (VG), such as wind and solar, and (3) the variability and uncertainty of this VG. As power systems begin to incorporate higher shares of VG, many questions arise about the suitability of the existing marginal-cost-based price formation, primarily within an energy-only market structure, to ensure the economic viability of resources that might be needed to provide system reliability. This article discusses these questions and provides a summary of completed and ongoing modelling-based work at the National Renewable Energy Laboratory to better understand the impacts of evolving power systems on reliability and revenue sufficiency.

Optimization of Reliability Centered Maintenance Bassed on Maintenance Costs and Reliability with Consideration of Location of Components

Directory of Open Access Journals (Sweden)

Mahdi Karbasian

2011-03-01

Full Text Available The reliability of designing systems such as electrical and electronic circuits, power generation/ distribution networks and mechanical systems, in which the failure of a component may cause the whole system failure, and even the reliability of cellular manufacturing systems that their machines are connected to as series are critically important. So far approaches for improving the reliability of these systems have been mainly based on the enhancement of inherent reliability of any system component or increasing system reliability based on maintenance strategies. Also in some of the resources, only the influence of the location of systems' components on reliability is studied. Therefore, it seems other approaches have been rarely applied. In this paper, a multi criteria model has been proposed to perform a balance among a system's reliability, location costs, and its system maintenance. Finally, a numerical example has been presented and solved by the Lingo software.

Seeking high reliability in primary care: Leadership, tools, and organization.

Science.gov (United States)

Weaver, Robert R

2015-01-01

Leaders in health care increasingly recognize that improving health care quality and safety requires developing an organizational culture that fosters high reliability and continuous process improvement. For various reasons, a reliability-seeking culture is lacking in most health care settings. Developing a reliability-seeking culture requires leaders' sustained commitment to reliability principles using key mechanisms to embed those principles widely in the organization. The aim of this study was to examine how key mechanisms used by a primary care practice (PCP) might foster a reliability-seeking, system-oriented organizational culture. A case study approach was used to investigate the PCP's reliability culture. The study examined four cultural artifacts used to embed reliability-seeking principles across the organization: leadership statements, decision support tools, and two organizational processes. To decipher their effects on reliability, the study relied on observations of work patterns and the tools' use, interactions during morning huddles and process improvement meetings, interviews with clinical and office staff, and a "collective mindfulness" questionnaire. The five reliability principles framed the data analysis. Leadership statements articulated principles that oriented the PCP toward a reliability-seeking culture of care. Reliability principles became embedded in the everyday discourse and actions through the use of "problem knowledge coupler" decision support tools and daily "huddles." Practitioners and staff were encouraged to report unexpected events or close calls that arose and which often initiated a formal "process change" used to adjust routines and prevent adverse events from recurring. Activities that foster reliable patient care became part of the taken-for-granted routine at the PCP. The analysis illustrates the role leadership, tools, and organizational processes play in developing and embedding a reliable-seeking culture across an

Flash memories economic principles of performance, cost and reliability optimization

CERN Document Server

Richter, Detlev

2014-01-01

The subject of this book is to introduce a model-based quantitative performance indicator methodology applicable for performance, cost and reliability optimization of non-volatile memories. The complex example of flash memories is used to introduce and apply the methodology. It has been developed by the author based on an industrial 2-bit to 4-bit per cell flash development project. For the first time, design and cost aspects of 3D integration of flash memory are treated in this book. Cell, array, performance and reliability effects of flash memories are introduced and analyzed. Key performance parameters are derived to handle the flash complexity. A performance and array memory model is developed and a set of performance indicators characterizing architecture, cost and durability is defined.   Flash memories are selected to apply the Performance Indicator Methodology to quantify design and technology innovation. A graphical representation based on trend lines is introduced to support a requirement based pr...

48 CFR 31.205-27 - Organization costs.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Organization costs. 31.205... CONTRACTING REQUIREMENTS CONTRACT COST PRINCIPLES AND PROCEDURES Contracts With Commercial Organizations 31.205-27 Organization costs. (a) Except as provided in paragraph (b) of this section, expenditures in...

Reliability Assessment for Low-cost Unmanned Aerial Vehicles

Science.gov (United States)

Freeman, Paul Michael

Existing low-cost unmanned aerospace systems are unreliable, and engineers must blend reliability analysis with fault-tolerant control in novel ways. This dissertation introduces the University of Minnesota unmanned aerial vehicle flight research platform, a comprehensive simulation and flight test facility for reliability and fault-tolerance research. An industry-standard reliability assessment technique, the failure modes and effects analysis, is performed for an unmanned aircraft. Particular attention is afforded to the control surface and servo-actuation subsystem. Maintaining effector health is essential for safe flight; failures may lead to loss of control incidents. Failure likelihood, severity, and risk are qualitatively assessed for several effector failure modes. Design changes are recommended to improve aircraft reliability based on this analysis. Most notably, the control surfaces are split, providing independent actuation and dual-redundancy. The simulation models for control surface aerodynamic effects are updated to reflect the split surfaces using a first-principles geometric analysis. The failure modes and effects analysis is extended by using a high-fidelity nonlinear aircraft simulation. A trim state discovery is performed to identify the achievable steady, wings-level flight envelope of the healthy and damaged vehicle. Tolerance of elevator actuator failures is studied using familiar tools from linear systems analysis. This analysis reveals significant inherent performance limitations for candidate adaptive/reconfigurable control algorithms used for the vehicle. Moreover, it demonstrates how these tools can be applied in a design feedback loop to make safety-critical unmanned systems more reliable. Control surface impairments that do occur must be quickly and accurately detected. This dissertation also considers fault detection and identification for an unmanned aerial vehicle using model-based and model-free approaches and applies those

Reliability-oriented Design of a Cost-effective Active Capacitor

DEFF Research Database (Denmark)

Wang, Haoran; Wang, Huai

2017-01-01

This paper presents the reliability-oriented design of a two-terminal active capacitor proposed recently. The two-terminal active capacitor has the same level of convenience as a passive capacitor with reduced requirement of overall energy storage. In order to fully explore the potential...... of the proposed concept, a comprehensive design procedure is necessary to optimally sizing the key components of the active capacitor in terms of cost and reliability. Moreover, the inherent condition monitoring capability of the active capacitor is discussed by utilizing the existing feedback signals. A 500 W...

In search of cost-effective, reliable software

International Nuclear Information System (INIS)

Naser, J.A.; Bhatt, S.C.

1992-01-01

Considerable effort is ongoing to utilize the strengths of digital technology to upgrade and add functionality to existing systems and to develop solutions to problems in the nuclear industry. Acceptance of digital solutions requires verification and validation activities to ensure the reliability and acceptance of these solutions. EPRI has an ongoing effort to develop a methodology for verification and validation of digital control systems. Also, a joint project between the NRC and EPRI is developing a methodology for expert system verification and validation. To obtain a wider acceptance of digital system solutions and hence the utilization of verification and validation techniques, cost effective methods for design, development and verification and validation are needed. EPRI is leading an effort to develop methods for cost effective verification and validation for all types of software

Replacement energy, capacity, and reliability costs for permanent nuclear reactor shutdowns

International Nuclear Information System (INIS)

VanKuiken, J.C., Buehring, W.A.; Hamilton, S.; Kavicky, J.A.; Cavallo, J.D.; Veselka, T.D.; Willing, D.L.

1993-10-01

Average replacement power costs are estimated for potential permanent shutdowns of nuclear electricity-generating units. Replacement power costs are considered to include replacement energy, capacity, and reliability cost components. These estimates were developed to assist the US Nuclear Regulatory Commission in evaluating regulatory issues that potentially affect changes in serious reactor accident frequencies. Cost estimates were derived from long-term production-cost and capacity expansion simulations of pooled utility-system operations. Factors that affect replacement power cost, such as load growth, replacement sources of generation, and capital costs for replacement capacity, were treated in the analysis. Costs are presented for a representative reactor and for selected subcategories of reactors, based on estimates for 112 individual reactors

The Reliability, Impact, and Cost-Effectiveness of Value-Added Teacher Assessment Methods

Science.gov (United States)

Yeh, Stuart S.

2012-01-01

This article reviews evidence regarding the intertemporal reliability of teacher rankings based on value-added methods. Value-added methods exhibit low reliability, yet are broadly supported by prominent educational researchers and are increasingly being used to evaluate and fire teachers. The article then presents a cost-effectiveness analysis…

76 FR 16263 - Revision to Electric Reliability Organization Definition of Bulk Electric System

Science.gov (United States)

2011-03-23

...; Order No. 743-A] Revision to Electric Reliability Organization Definition of Bulk Electric System AGENCY... certain provisions of the Final Rule. Order No. 743 directed the Electric Reliability Organization (ERO) to revise the definition of the term ``bulk electric system'' through the ERO's Reliability Standards...

75 FR 72909 - Revision to Electric Reliability Organization Definition of Bulk Electric System

Science.gov (United States)

2010-11-26

... Bulk-Power System. See Rules Concerning Certification of the Electric Reliability Organization; and... Bulk-Power System in North America because it protects the reliability of the bulk electric system and... Electric Reliability Organization Definition of Bulk Electric System; Final Rule #0;#0;Federal Register...

Modeling Optimal Scheduling for Pumping System to Minimize Operation Cost and Enhance Operation Reliability

Directory of Open Access Journals (Sweden)

Yin Luo

2012-01-01

Full Text Available Traditional pump scheduling models neglect the operation reliability which directly relates with the unscheduled maintenance cost and the wear cost during the operation. Just for this, based on the assumption that the vibration directly relates with the operation reliability and the degree of wear, it could express the operation reliability as the normalization of the vibration level. The characteristic of the vibration with the operation point was studied, it could be concluded that idealized flow versus vibration plot should be a distinct bathtub shape. There is a narrow sweet spot (80 to 100 percent BEP to obtain low vibration levels in this shape, and the vibration also follows similar law with the square of the rotation speed without resonance phenomena. Then, the operation reliability could be modeled as the function of the capacity and rotation speed of the pump and add this function to the traditional model to form the new. And contrast with the tradition method, the result shown that the new model could fix the result produced by the traditional, make the pump operate in low vibration, then the operation reliability could increase and the maintenance cost could decrease.

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

DEFF Research Database (Denmark)

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

2012-01-01

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...

75 FR 80391 - Electric Reliability Organization Interpretations of Interconnection Reliability Operations and...

Science.gov (United States)

2010-12-22

... transmission (G&T) cooperative or similar organization to accept compliance responsibility on behalf of its... be found on the Commission's Web site; see, e.g., the ``Quick Reference Guide for Paper Submissions... Electric Reliability Standards, Order No. 672, FERC Stats. & Regs. ] 31,204, order on reh'g, Order No. 672...

Business Cases for Microgrids: Modeling Interactions of Technology Choice, Reliability, Cost, and Benefit

Science.gov (United States)

Hanna, Ryan

Distributed energy resources (DERs), and increasingly microgrids, are becoming an integral part of modern distribution systems. Interest in microgrids--which are insular and autonomous power networks embedded within the bulk grid--stems largely from the vast array of flexibilities and benefits they can offer stakeholders. Managed well, they can improve grid reliability and resiliency, increase end-use energy efficiency by coupling electric and thermal loads, reduce transmission losses by generating power locally, and may reduce system-wide emissions, among many others. Whether these public benefits are realized, however, depends on whether private firms see a "business case", or private value, in investing. To this end, firms need models that evaluate costs, benefits, risks, and assumptions that underlie decisions to invest. The objectives of this dissertation are to assess the business case for microgrids that provide what industry analysts forecast as two primary drivers of market growth--that of providing energy services (similar to an electric utility) as well as reliability service to customers within. Prototypical first adopters are modeled--using an existing model to analyze energy services and a new model that couples that analysis with one of reliability--to explore interactions between technology choice, reliability, costs, and benefits. The new model has a bi-level hierarchy; it uses heuristic optimization to select and size DERs and analytical optimization to schedule them. It further embeds Monte Carlo simulation to evaluate reliability as well as regression models for customer damage functions to monetize reliability. It provides least-cost microgrid configurations for utility customers who seek to reduce interruption and operating costs. Lastly, the model is used to explore the impact of such adoption on system-wide greenhouse gas emissions in California. Results indicate that there are, at present, co-benefits for emissions reductions when customers

The reliability of running economy expressed as oxygen cost and energy cost in trained distance runners.

Science.gov (United States)

Shaw, Andrew J; Ingham, Stephen A; Fudge, Barry W; Folland, Jonathan P

2013-12-01

This study assessed the between-test reliability of oxygen cost (OC) and energy cost (EC) in distance runners, and contrasted it with the smallest worthwhile change (SWC) of these measures. OC and EC displayed similar levels of within-subject variation (typical error < 3.85%). However, the typical error (2.75% vs 2.74%) was greater than the SWC (1.38% vs 1.71%) for both OC and EC, respectively, indicating insufficient sensitivity to confidently detect small, but meaningful, changes in OC and EC.

Cost Evaluation of a Donation after Cardiac Death Program: How Cost per Organ Compares to Other Donor Types.

Science.gov (United States)

Lindemann, Jessica; Dageforde, Leigh Anne; Vachharajani, Neeta; Stahlschmidt, Emily; Brockmeier, Diane; Wellen, Jason R; Khan, Adeel; Chapman, William C; Doyle, Mb Majella

2018-05-01

Donation after cardiac death (DCD) is one method of organ donation. Nationally, more than half of evaluated DCD donors do not yield transplantable organs. There is no algorithm for predicting which DCD donors will be appropriate for organ procurement. Donation after cardiac death program costs from an organ procurement organization (OPO) accounting for all evaluated donors have not been reported. Hospital, transportation, and supply costs of potential DCD donors evaluated at a single OPO from January 2009 to June 2016 were collected. Mean costs per donor and per organ were calculated. Cost of DCD donors that did not yield a transplantable organ were included in cost analyses resulting in total cost of the DCD program. Donation after cardiac death donor costs were compared with costs of in-hospital donation after brain death (DBD) donors. There were 289 organs transplanted from 264 DCD donors evaluated. Mean cost per DCD donor yielding transplantable organs was $9,306. However, 127 donors yielded no organs, at a mean cost of $8,794 per donor. The total cost of the DCD program was $32,020 per donor and $15,179 per organ. Mean cost for an in-hospital DBD donor was $33,546 and $9,478 per organ transplanted. Mean organ yield for DBD donors was 3.54 vs 2.21 for DCD donors (p organ 63% of the cost of a DCD organ. Mean cost per DCD donor is comparable with DBD donors, however, individual cost of DCD organs increases by almost 40% when all costs of an entire DCD program are included. Published by Elsevier Inc.

Reliability of optical fibres and components final report of COST 246

CERN Document Server

Griffioen, Willem; Gadonna, Michel; Limberger, Hans; Heens, Bernard; Knuuttila, Hanna; Kurkjian, Charles; Mirza, Shehzad; Opacic, Aleksandar; Regio, Paola; Semjonov, Sergei

1999-01-01

Reliability of Optical Fibres and Components reports the findings of COST 246 (1993-1998) - European research initiative in the field of optical telecommunications. Experts in the materials and reliability field of optical fibres and components have contributed to this unique study programme. The results, conclusions and achievements of their work have been obtained through joint experimentation and discussion with representatives from manufacturing and research groups. Topics covered include: Lifetime estimation; Failure mechanisms; Ageing test methods; Field data and service environments for components. For the first time the reader can explore the reliability of products and examine the results and conclusions in published form. This comprehensive volume is intended to provide a deeper understanding of the reliability of optical fibres and components. The book will be extremely useful to all scientists and practitioners involved in the industry.

Leadership in organizations with high security and reliability requirements

International Nuclear Information System (INIS)

Gonzalez, F.

2013-01-01

Developing leadership skills in organizations is the key to ensure the sustainability of excellent results in industries with high requirements safety and reliability. In order to have a model of leadership development specific to this type of organizations, Tecnatom in 2011, we initiated a project internal, to find and adapt a competency model to these requirements.

Cost-effectiveness of combustion turbines: recommendations for reliability, maintainability, supportability and maintenance requirements

Energy Technology Data Exchange (ETDEWEB)

Meuwisse, C; Despujols, A [Electricite de France, Research and Development Division, Chatou (France); Givaudan, B [Electricite de France, Research and Development Division - SEPTEN, Villeurbanne (France); Lafage, L [Electricite de France, Engineering and Construction Division - CNET, Paris (France)

1999-12-31

The profitability of combustion turbines intended for export is of extreme importance for Electricite de France. It is principally during the development phase of a project that one can ensure resect of two indissociable factors, essential to the per-kWh production cost: global operating costs and performance in terms of reliability and availability. The approach proposed here advocates the global acquisition of the installation and its logistic support. Generally applicable recommendations are given. They enable integrating in the future plant specifications all requirements relative to plant reliability, availability, maintainability and logistic support. They are structured according to type: expression of needs and management factors. (orig.) 4 refs.

Cost-effectiveness of combustion turbines: recommendations for reliability, maintainability, supportability and maintenance requirements

Energy Technology Data Exchange (ETDEWEB)

Meuwisse, C.; Despujols, A. [Electricite de France, Research and Development Division, Chatou (France); Givaudan, B. [Electricite de France, Research and Development Division - SEPTEN, Villeurbanne (France); Lafage, L. [Electricite de France, Engineering and Construction Division - CNET, Paris (France)

1998-12-31

The profitability of combustion turbines intended for export is of extreme importance for Electricite de France. It is principally during the development phase of a project that one can ensure resect of two indissociable factors, essential to the per-kWh production cost: global operating costs and performance in terms of reliability and availability. The approach proposed here advocates the global acquisition of the installation and its logistic support. Generally applicable recommendations are given. They enable integrating in the future plant specifications all requirements relative to plant reliability, availability, maintainability and logistic support. They are structured according to type: expression of needs and management factors. (orig.) 4 refs.

Cost/worth assessment of reliability improvement in distribution networks by means of artificial intelligence

Energy Technology Data Exchange (ETDEWEB)

Bouhouras, Aggelos S.; Labridis, Dimitris P.; Bakirtzis, Anastasios G. [Power Systems Laboratory, Aristotle University of Thessaloniki, Dept. of Electrical and Computer Engineering, 54124 Thessaloniki (Greece)

2010-06-15

A major challenge for the power utilities today is to ensure a high level of reliability of supply to customers. Two main factors determine the feasibility of a project that improves the reliability of supply: the project cost (investment and operational) and the benefits that result from the implementation of the project. This paper examines the implementation of an Artificial Intelligence System in an urban distribution network, capable to locate and isolate short circuit faults in the feeder, thus accomplishing immediate restoration of electric supply to the customers. The paper describes the benefits of the project, which are supply reliability improvement and distribution network loss reduction through network reconfigurations. By comparison of the project benefits and costs the economic feasibility of such a project for an underground distribution feeder in Greece is demonstrated. (author)

Offshore compression system design for low cost high and reliability

Energy Technology Data Exchange (ETDEWEB)

Castro, Carlos J. Rocha de O.; Carrijo Neto, Antonio Dias; Cordeiro, Alexandre Franca [Chemtech Engineering Services and Software Ltd., Rio de Janeiro, RJ (Brazil). Special Projects Div.], Emails: antonio.carrijo@chemtech.com.br, carlos.rocha@chemtech.com.br, alexandre.cordeiro@chemtech.com.br

2010-07-01

In the offshore oil fields, the oil streams coming from the wells usually have significant amounts of gas. This gas is separated at low pressure and has to be compressed to the export pipeline pressure, usually at high pressure to reduce the needed diameter of the pipelines. In the past, this gases where flared, but nowadays there are a increasing pressure for the energy efficiency improvement of the oil rigs and the use of this gaseous fraction. The most expensive equipment of this kind of plant are the compression and power generation systems, being the second a strong function of the first, because the most power consuming equipment are the compressors. For this reason, the optimization of the compression system in terms of efficiency and cost are determinant to the plant profit. The availability of the plants also have a strong influence in the plant profit, specially in gas fields where the products have a relatively low aggregated value, compared to oil. Due this, the third design variable of the compression system becomes the reliability. As high the reliability, larger will be the plant production. The main ways to improve the reliability of compression system are the use of multiple compression trains in parallel, in a 2x50% or 3x50% configuration, with one in stand-by. Such configurations are possible and have some advantages and disadvantages, but the main side effect is the increase of the cost. This is the offshore common practice, but that does not always significantly improve the plant availability, depending of the previous process system. A series arrangement and a critical evaluation of the overall system in some cases can provide a cheaper system with equal or better performance. This paper shows a case study of the procedure to evaluate a compression system design to improve the reliability but without extreme cost increase, balancing the number of equipment, the series or parallel arrangement, and the driver selection. Two cases studies will be

Validity and reliability of a low-cost digital dynamometer for measuring isometric strength of lower limb.

Science.gov (United States)

Romero-Franco, Natalia; Jiménez-Reyes, Pedro; Montaño-Munuera, Juan A

2017-11-01

Lower limb isometric strength is a key parameter to monitor the training process or recognise muscle weakness and injury risk. However, valid and reliable methods to evaluate it often require high-cost tools. The aim of this study was to analyse the concurrent validity and reliability of a low-cost digital dynamometer for measuring isometric strength in lower limb. Eleven physically active and healthy participants performed maximal isometric strength for: flexion and extension of ankle, flexion and extension of knee, flexion, extension, adduction, abduction, internal and external rotation of hip. Data obtained by the digital dynamometer were compared with the isokinetic dynamometer to examine its concurrent validity. Data obtained by the digital dynamometer from 2 different evaluators and 2 different sessions were compared to examine its inter-rater and intra-rater reliability. Intra-class correlation (ICC) for validity was excellent in every movement (ICC > 0.9). Intra and inter-tester reliability was excellent for all the movements assessed (ICC > 0.75). The low-cost digital dynamometer demonstrated strong concurrent validity and excellent intra and inter-tester reliability for assessing isometric strength in the main lower limb movements.

18 CFR 39.10 - Changes to an Electric Reliability Organization Rule or Regional Entity Rule.

Science.gov (United States)

2010-04-01

... RULES CONCERNING CERTIFICATION OF THE ELECTRIC RELIABILITY ORGANIZATION; AND PROCEDURES FOR THE ESTABLISHMENT, APPROVAL, AND ENFORCEMENT OF ELECTRIC RELIABILITY STANDARDS § 39.10 Changes to an Electric... Reliability Organization Rule or Regional Entity Rule. 39.10 Section 39.10 Conservation of Power and Water...

Highly Conductive and Reliable Copper-Filled Isotropically Conductive Adhesives Using Organic Acids for Oxidation Prevention

Science.gov (United States)

Chen, Wenjun; Deng, Dunying; Cheng, Yuanrong; Xiao, Fei

2015-07-01

The easy oxidation of copper is one critical obstacle to high-performance copper-filled isotropically conductive adhesives (ICAs). In this paper, a facile method to prepare highly reliable, highly conductive, and low-cost ICAs is reported. The copper fillers were treated by organic acids for oxidation prevention. Compared with ICA filled with untreated copper flakes, the ICA filled with copper flakes treated by different organic acids exhibited much lower bulk resistivity. The lowest bulk resistivity achieved was 4.5 × 10-5 Ω cm, which is comparable to that of commercially available Ag-filled ICA. After 500 h of 85°C/85% relative humidity (RH) aging, the treated ICAs showed quite stable bulk resistivity and relatively stable contact resistance. Through analyzing the results of x-ray diffraction, x-ray photoelectron spectroscopy, and thermogravimetric analysis, we found that, with the assistance of organic acids, the treated copper flakes exhibited resistance to oxidation, thus guaranteeing good performance.

A critical evaluation of deterministic methods in size optimisation of reliable and cost effective standalone hybrid renewable energy systems

International Nuclear Information System (INIS)

Maheri, Alireza

2014-01-01

Reliability of a hybrid renewable energy system (HRES) strongly depends on various uncertainties affecting the amount of power produced by the system. In the design of systems subject to uncertainties, both deterministic and nondeterministic design approaches can be adopted. In a deterministic design approach, the designer considers the presence of uncertainties and incorporates them indirectly into the design by applying safety factors. It is assumed that, by employing suitable safety factors and considering worst-case-scenarios, reliable systems can be designed. In fact, the multi-objective optimisation problem with two objectives of reliability and cost is reduced to a single-objective optimisation problem with the objective of cost only. In this paper the competence of deterministic design methods in size optimisation of reliable standalone wind–PV–battery, wind–PV–diesel and wind–PV–battery–diesel configurations is examined. For each configuration, first, using different values of safety factors, the optimal size of the system components which minimises the system cost is found deterministically. Then, for each case, using a Monte Carlo simulation, the effect of safety factors on the reliability and the cost are investigated. In performing reliability analysis, several reliability measures, namely, unmet load, blackout durations (total, maximum and average) and mean time between failures are considered. It is shown that the traditional methods of considering the effect of uncertainties in deterministic designs such as design for an autonomy period and employing safety factors have either little or unpredictable impact on the actual reliability of the designed wind–PV–battery configuration. In the case of wind–PV–diesel and wind–PV–battery–diesel configurations it is shown that, while using a high-enough margin of safety in sizing diesel generator leads to reliable systems, the optimum value for this margin of safety leading to a

Educational Management Organizations as High Reliability Organizations: A Study of Victory's Philadelphia High School Reform Work

Science.gov (United States)

Thomas, David E.

2013-01-01

This executive position paper proposes recommendations for designing reform models between public and private sectors dedicated to improving school reform work in low performing urban high schools. It reviews scholarly research about for-profit educational management organizations, high reliability organizations, American high school reform, and…

Reliability and cost evaluation of small isolated power systems containing photovoltaic and wind energy

Science.gov (United States)

Karki, Rajesh

Renewable energy application in electric power systems is growing rapidly worldwide due to enhanced public concerns for adverse environmental impacts and escalation in energy costs associated with the use of conventional energy sources. Photovoltaics and wind energy sources are being increasingly recognized as cost effective generation sources. A comprehensive evaluation of reliability and cost is required to analyze the actual benefits of utilizing these energy sources. The reliability aspects of utilizing renewable energy sources have largely been ignored in the past due the relatively insignificant contribution of these sources in major power systems, and consequently due to the lack of appropriate techniques. Renewable energy sources have the potential to play a significant role in the electrical energy requirements of small isolated power systems which are primarily supplied by costly diesel fuel. A relatively high renewable energy penetration can significantly reduce the system fuel costs but can also have considerable impact on the system reliability. Small isolated systems routinely plan their generating facilities using deterministic adequacy methods that cannot incorporate the highly erratic behavior of renewable energy sources. The utilization of a single probabilistic risk index has not been generally accepted in small isolated system evaluation despite its utilization in most large power utilities. Deterministic and probabilistic techniques are combined in this thesis using a system well-being approach to provide useful adequacy indices for small isolated systems that include renewable energy. This thesis presents an evaluation model for small isolated systems containing renewable energy sources by integrating simulation models that generate appropriate atmospheric data, evaluate chronological renewable power outputs and combine total available energy and load to provide useful system indices. A software tool SIPSREL+ has been developed which generates

Promoting Organ Donor Registries Through Public Education: What Is the Cost of Securing Organ Donors?

Science.gov (United States)

Razdan, Manik; Smith, Kenneth J; Bryce, Cindy L; Degenholtz, Howard B

2016-06-01

Transplant medicine's impact on America's public health is seriously limited by acute shortage of transplantable organs. Consequently, the United Sates has witnessed considerable investment in the promotion of organ donor registries. Although there is no evidence to support that donor registry promotion alleviates organ shortage, this belief continues to drive investments into registry promotion. In this study, return on investment in donor registry promotion was examined using cost-outcomes analysis. Cost of promoting the donor registry was estimated in US dollars whereas the outcome was measured as the number of individuals who join the registry (registrants) and their value in terms of organ donors. The study was conducted from the perspective of a regional Organ Procurement Organization (OPO). Costs were directly obtained from the OPO. The number of new registrants was obtained from the OPO and the departments of motor vehicles that maintain the donor registry. The value of registrants in terms of organ donors was computed based on a registrant's age-dependent risk of dying and age-dependent probability of becoming an organ donor. Six thousand seven hundred eight individuals joined the organ donor registry (95% confidence interval [95% CI], 5429-7956) at a cost of $455 per registrant (95% CI, US $383-US $562). These individuals result in 4.2 present-day donors (95% CI, 2.5-6.6) at a cost of US $726 000 (95% CI, US $462000-US $1.2 million). Because the cost per registrant and cost per donor is less than society's willingness to pay, donor registry promotion offers positive return on investment. Investment in registry promotion should at the minimum be maintained at current levels.

Third sector organizations in rural development: a transaction cost perspective

Directory of Open Access Journals (Sweden)

V. VALENTINOV

2008-12-01

Full Text Available In many parts of the world, rural development is supported by third sector organizations, such as nongovernmental organizations, farmer associations, and cooperatives. This essay develops a transaction cost explanation of these organizations’ role in rural areas. Since the traditional transaction cost theory is concerned with the choice of governance mechanisms within the for-profit sector, this essay adopts an alternative conceptualization of the notion of transaction cost by building on the theory of the division of labor. This theory regards transaction cost as a constraint on the division of labor causing the replacement of exchange with self-sufficiency. The proposed transaction cost explanation of rural third sector organizations consists of two arguments: 1 third sector organizations embody partial reliance on self-sufficiency; and 2 rural areas exhibit rurality-specific transaction cost acting as a constraint on the division of labor and thus creating a niche for third sector organizations. The essay concludes with suggesting a research program on developing an economic theory of the rural third sector.;

78 FR 29209 - Revisions to Electric Reliability Organization Definition of Bulk Electric System and Rules of...

Science.gov (United States)

2013-05-17

... Commission 18 CFR Part 40 Revisions to Electric Reliability Organization Definition of Bulk Electric System... local distribution'' as set forth in the Federal Power Act (FPA). \\1\\ Revisions to Electric Reliability... Reliability Organization Definition of Bulk Electric System, Order No. 743, 133 FERC ] 61,150, at P 16 (2010...

Accountable Care Organizations and Transaction Cost Economics.

Science.gov (United States)

Mick, Stephen S Farnsworth; Shay, Patrick D

2016-12-01

Using a Transaction Cost Economics (TCE) approach, this paper explores which organizational forms Accountable Care Organizations (ACOs) may take. A critical question about form is the amount of vertical integration that an ACO may have, a topic central to TCE. We posit that contextual factors outside and inside an ACO will produce variable transaction costs (the non-production costs of care) such that the decision to integrate vertically will derive from a comparison of these external versus internal costs, assuming reasonably rational management abilities. External costs include those arising from environmental uncertainty and complexity, small numbers bargaining, asset specificity, frequency of exchanges, and information "impactedness." Internal costs include those arising from human resource activities including hiring and staffing, training, evaluating (i.e., disciplining, appraising, or promoting), and otherwise administering programs. At the extreme, these different costs may produce either total vertical integration or little to no vertical integration with most ACOs falling in between. This essay demonstrates how TCE can be applied to the ACO organization form issue, explains TCE, considers ACO activity from the TCE perspective, and reflects on research directions that may inform TCE and facilitate ACO development. © The Author(s) 2016.

Learning Organizations in High Reliability Industries

International Nuclear Information System (INIS)

Schwalbe, D.; Wächter, C.

2016-01-01

Full text: Humans make mistakes. Sometimes we learn from them. In a high reliability organization we have to learn before an error leads to an incident (or even accident). Therefore the “human factor” is most important as most of the time the human is the last line of defense. The “human factor” is more than communication or leadership skills. At the end, it is the personal attitude. This attitude has to be safety minded. And this attitude has to be self-reflected continuously. Moreover, feedback from others is urgently needed to improve one’s personal skills daily and learn from our own experience as well as from others. (author

Optimizing inspection intervals—Reliability and availability in terms of a cost model: A case study on railway carriers

International Nuclear Information System (INIS)

Wolde, Mike ten; Ghobbar, Adel A.

2013-01-01

This paper states the problem that railway carriers have with inspections and maintenance in its most cost optimal way. Often there is external pressure to improve reliability and availability and to reduce costs significantly. To overcome this problem this paper suggests a model that tries to find the optimal inspection interval. Not all maintenance companies have their inspection intervals that match with the actual reliability of a system anymore and the inspection intervals are not necessarily at a cost optimum. This research retrieves the actual failure and repair data and combines this together with the availability of a system to find the optimum inspection interval in terms of costs. The application of the optimization approach to a railway carrier maintenance company in the Netherlands is also presented. -- Highlights: ► New optimization technique for reliability and availability by minimizing costs. ► Adaptable to multiple types of repairs. ► Usable as a practical model. ► Applicable to the FMECA, RCM and ISO31000 risk management methods

Balancing low cost with reliable operation in the rotordynamic design of the ALS Liquid Hydrogen Fuel Turbopump

Science.gov (United States)

Greenhill, L. M.

1990-01-01

The Air Force/NASA Advanced Launch System (ALS) Liquid Hydrogen Fuel Turbopump (FTP) has primary design goals of low cost and high reliability, with performance and weight having less importance. This approach is atypical compared with other rocket engine turbopump design efforts, such as on the Space Shuttle Main Engine (SSME), which emphasized high performance and low weight. Similar to the SSME turbopumps, the ALS FTP operates supercritically, which implies that stability and bearing loads strongly influence the design. In addition, the use of low cost/high reliability features in the ALS FTP such as hydrostatic bearings, relaxed seal clearances, and unshrouded turbine blades also have a negative influence on rotordynamics. This paper discusses the analysis conducted to achieve a balance between low cost and acceptable rotordynamic behavior, to ensure that the ALS FTP will operate reliably without subsynchronous instabilities or excessive bearing loads.

On-line determination of operating limits incorporating constraint costs and reliability assessment

International Nuclear Information System (INIS)

Meisingset, M.; Lovas, G. G.

1997-01-01

Problems regarding power system operation following deregulation were discussed. The problems arise as a result of the increased power flow pattern created by deregulation and competitive power markets, resulting in power in excess of N-1, (the capacity of transmission lines available), which in turn creates bottlenecks. In a situation like this, constraint costs and security costs (i.e. the cost of supply interruptions) are incurred as the direct result of the deterministic criteria used in reliability assessment. This paper describes an on-line probabilistic method to determine operating limits based on a trade-off between constraint costs and security costs. The probability of the contingencies depend on the existing weather conditions, which therefore has significant impact on the calculated operating limit. In consequence, the proposed method allows power flow to exceed the N-1 limit during normal weather. Under adverse weather conditions the N-1 criteria should be maintained. 15 refs., 13 figs

Software reliability

CERN Document Server

Bendell, A

1986-01-01

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

Business of reliability

Science.gov (United States)

Engel, Pierre

1999-12-01

The presentation is organized around three themes: (1) The decrease of reception equipment costs allows non-Remote Sensing organization to access a technology until recently reserved to scientific elite. What this means is the rise of 'operational' executive agencies considering space-based technology and operations as a viable input to their daily tasks. This is possible thanks to totally dedicated ground receiving entities focusing on one application for themselves, rather than serving a vast community of users. (2) The multiplication of earth observation platforms will form the base for reliable technical and financial solutions. One obstacle to the growth of the earth observation industry is the variety of policies (commercial versus non-commercial) ruling the distribution of the data and value-added products. In particular, the high volume of data sales required for the return on investment does conflict with traditional low-volume data use for most applications. Constant access to data sources supposes monitoring needs as well as technical proficiency. (3) Large volume use of data coupled with low- cost equipment costs is only possible when the technology has proven reliable, in terms of application results, financial risks and data supply. Each of these factors is reviewed. The expectation is that international cooperation between agencies and private ventures will pave the way for future business models. As an illustration, the presentation proposes to use some recent non-traditional monitoring applications, that may lead to significant use of earth observation data, value added products and services: flood monitoring, ship detection, marine oil pollution deterrent systems and rice acreage monitoring.

Reliability-Based Marginal Cost Pricing Problem Case with Both Demand Uncertainty and Travelers’ Perception Errors

Directory of Open Access Journals (Sweden)

Shaopeng Zhong

2013-01-01

Full Text Available Focusing on the first-best marginal cost pricing (MCP in a stochastic network with both travel demand uncertainty and stochastic perception errors within the travelers’ route choice decision processes, this paper develops a perceived risk-based stochastic network marginal cost pricing (PRSN-MCP model. Numerical examples based on an integrated method combining the moment analysis approach, the fitting distribution method, and the reliability measures are also provided to demonstrate the importance and properties of the proposed model. The main finding is that ignoring the effect of travel time reliability and travelers’ perception errors may significantly reduce the performance of the first-best MCP tolls, especially under high travelers’ confidence and network congestion levels. The analysis result could also enhance our understanding of (1 the effect of stochastic perception error (SPE on the perceived travel time distribution and the components of road toll; (2 the effect of road toll on the actual travel time distribution and its reliability measures; (3 the effect of road toll on the total network travel time distribution and its statistics; and (4 the effect of travel demand level and the value of reliability (VoR level on the components of road toll.

75 FR 54590 - Notice of 2010 National Organic Certification Cost-Share Program

Science.gov (United States)

2010-09-08

...] Notice of 2010 National Organic Certification Cost-Share Program AGENCY: Agricultural Marketing Service... Certification Cost-Share Funds. The AMS has allocated $22.0 million for this organic certification cost-share... National Organic Certification Cost- Share Program is authorized under 7 U.S.C. 6523, as amended by section...

Advancements in valve technology and industry lessons lead to improved plant reliability and cost savings

International Nuclear Information System (INIS)

Sharma, V.; Kalsi, M.S.

2005-01-01

Plant reliability and safety hinges on the proper functioning of several valves. Recent advancements in valve technology have resulted in new analytical and test methods for evaluating and improving valve and actuator reliability. This is especially significant in critical service applications in which the economic impact of a valve failure on production, outage schedules and consequential damages far surpasses the initial equipment purchase price. This paper presents an overview of recent advances in valve technology driven by reliability concerns and cost savings objectives without comprising safety in the Nuclear Power Industry. This overview is based on over 27 years of experience in supporting US and International nuclear power utilities, and contributing to EPRI, and NSSS Owners' Groups in developing generic models/methodologies to address industry wide issues; performing design basis reviews; and implementing plant-wide valve reliability improvement programs. Various analytical prediction software and hardware solutions and training seminars are now available to implement valve programs covering power plants' lifecycle from the construction phase through life extension and power up rate. These tools and methodologies can enhance valve-engineering activities including the selection, sizing, proper application, condition monitoring, failure analysis, and condition based maintenance optimization with a focus on potential bad actors. This paper offers two such examples, the Kalsi Valve and Actuator Program (KVAP) and Check Valve Analysis and Prioritization (CVAP) [1-3, 8, 9, 11-13]. The advanced, validated torque prediction models incorporated into KVAP software for AOVs and MOVs have improved reliability of margin predictions and enabled cost savings through elimination of unwarranted equipment modifications. CVAP models provides a basis to prioritize the population of valves recommended for preventive maintenance, inspection and/or modification, allowing

Management systems for high reliability organizations. Integration and effectiveness; Managementsysteme fuer Hochzuverlaessigkeitsorganisationen. Integration und Wirksamkeit

Energy Technology Data Exchange (ETDEWEB)

Mayer, Michael

2015-03-09

The scope of the thesis is the development of a method for improvement of efficient integrated management systems for high reliability organizations (HRO). A comprehensive analysis of severe accident prevention is performed. Severe accident management, mitigation measures and business continuity management are not included. High reliability organizations are complex and potentially dynamic organization forms that can be inherently dangerous like nuclear power plants, offshore platforms, chemical facilities, large ships or large aircrafts. A recursive generic management system model (RGM) was development based on the following factors: systemic and cybernetic Asepcts; integration of different management fields, high decision quality, integration of efficient methods of safety and risk analysis, integration of human reliability aspects, effectiveness evaluation and improvement.

Modeling the reliability and maintenance costs of wind turbines using Weibull analysis

Energy Technology Data Exchange (ETDEWEB)

Vachon, W.A. [W.A. Vachon & Associates, Inc., Manchester, MA (United States)

1996-12-31

A general description is provided of the basic mathematics and use of Weibull statistical models for modeling component failures and maintenance costs as a function of time. The applicability of the model to wind turbine components and subsystems is discussed with illustrative examples of typical component reliabilities drawn from actual field experiences. Example results indicate the dominant role of key subsystems based on a combination of their failure frequency and repair/replacement costs. The value of the model is discussed as a means of defining (1) maintenance practices, (2) areas in which to focus product improvements, (3) spare parts inventory, and (4) long-term trends in maintenance costs as an important element in project cash flow projections used by developers, investors, and lenders. 6 refs., 8 figs., 3 tabs.

Accountability for enhanced reliability for ALWRs

International Nuclear Information System (INIS)

Sanford, M.O.

1993-01-01

Advanced nuclear units must compete with alternative generating technologies for inclusion in a utility's future planning. Operating reliability, or capacity factor, and operating cost are important factors in this competition. The ALWR Utility Requirements Document has established targets for both ALWR Capacity Factors (87%) and O ampersand M costs (13--16 mils/KWh), but recognizes that these O ampersand M cost targets need to be lower. The recently published USCEA cost study estimates O ampersand M costs on the order of 6 mils/kw. Meeting, or better yet improving on, these targets is essential for nuclear to be competitive. A number of specific items have been included in the Utility Requirements Document to improve reliability based on experience with operating units. For the most part, these include either avoiding known problems, or simplifying the design. Vendor design organizations are generally complying with the URD and this is expected to produce an improved design both in terms of reliability and ease of operation and maintenance. As one embarks on First-of-a-Kind Engineering (FOAKE), however, it is useful to revisit the issue of responsibility for assuring that reliability improvements are embodied in the new plant designs. The vendor design team must ultimately assume this responsibility. While utility operating and maintenance experience is an essential input to an effective design, decisions on how best to design for this experience remain a designer function. This poses a dilemma for the designer in that such decisions seem to invariably require a trade-off between the capital cost of the product and the ultimate O ampersand M cost. Since traditionally only capital cost has had a direct measurable impact on the vendor, it has received the greater weight. A more appropriate balance must be struck in the future, however, for nuclear to be competitive. Utilities must demand a balance in the design of ALWRs which truly reflects the total cost of power

76 FR 54999 - Notice of 2011 National Organic Certification Cost-Share Program

Science.gov (United States)

2011-09-06

...] Notice of 2011 National Organic Certification Cost-Share Program AGENCY: Agricultural Marketing Service... for the National Organic Certification Cost- Share Program. SUMMARY: This Notice invites all States of...) for the allocation of National Organic Certification Cost-Share Funds. Beginning in Fiscal Year 2008...

An examination of reliability critical items in liquid metal reactors: An analysis by the Centralized Reliability Data Organization (CREDO)

International Nuclear Information System (INIS)

Humphrys, B.L.; Haire, M.J.; Koger, K.H.; Manneschmidt, J.F.; Setoguchi, K.; Nakai, R.; Okubo, Y.

1987-01-01

The Centralized Reliability Data Organization (CREDO) is the largest repository of liquid metal reactor (LMR) component reliability data in the world. It is jointly sponsored by the US Department of Energy (DOE) and the Power Reactor and Nuclear Fuel Development Corporation (PNC) of Japan. The CREDO data base contains information on a population of more than 21,000 components and approximately 1300 event records. A conservative estimation is that the total component operating hours is approaching 3.5 billion hours. Because data gathering for CREDO concentrates on event (failure) information, the work reported here focuses on the reliability information contained in CREDO and the development of reliability critical items lists. That is, components are ranked in prioritized lists from worst to best performers from a reliability standpoint. For the data contained in the CREDO data base, FFTF and JOYO show reliability growth; EBR-II reveals a slight unreliability growth for those components tracked by CREDO. However, tabulations of events which cause reactor shutdowns decrease with time at each site

Design for Six Sigma: Approach for reliability and low-cost manufacturing.

Directory of Open Access Journals (Sweden)

Jesus Gerardo Cruz Alvarez

2012-07-01

Full Text Available The aim of this study is to discuss new product development based on a traditional stage-gate process and to examine how new product development [NPD] tools, such as lean design for Six Sigma, can accelerate the achievement of the main goals of NPD: reliable product quality, cost-effective implementation, and desired time-to-market. These new tools must be incorporated into a new approach to NPD based on the Advanced Product and Quality Planning methodology.

78 FR 5164 - Notice of Agricultural Management Assistance Organic Certification Cost-Share Program

Science.gov (United States)

2013-01-24

...] Notice of Agricultural Management Assistance Organic Certification Cost-Share Program AGENCY... Departments of Agriculture for the Agricultural Management Assistance Organic Certification Cost-Share Program... organic certification cost-share funds. The AMS has allocated $1.425 million for this organic...

76 FR 55000 - Notice of Agricultural Management Assistance Organic Certification Cost-Share Program

Science.gov (United States)

2011-09-06

...] Notice of Agricultural Management Assistance Organic Certification Cost-Share Program AGENCY... Departments of Agriculture for the Agricultural Management Assistance Organic Certification Cost-Share Program... organic certification cost-share funds. The AMS has allocated $1.5 million for this organic certification...

A reliable, compact and low-cost Michelson wavemeter for laser wavelength measurement

International Nuclear Information System (INIS)

Fox, P.J.; Scholten, R.E.; Walkiewicz, M.R.; Drullinger, R.E.

1998-01-01

We describe the construction and operation of a simple, compact and cost effective Michelson wavemeter with picometer accuracy. The low cost of the device means that it can form the basis of an undergraduate laboratory experiment, yet it is sufficiently reliable and accurate that it has become an important tool in our research laboratory, where it is regularly used to tune lasers to atomic transitions. The usefulness and accuracy of the wavemeter is demonstrated by tuning two separate extended cavity diode lasers to achieve two-step excitation of the Rb 5 2 D state, observed by detecting 420 nm blue fluorescence from the 5 2 D → 6 2 P → 5 2 S decay path. (authors)

On the Path to SunShot. The Role of Advancements in Solar Photovoltaic Efficiency, Reliability, and Costs

Energy Technology Data Exchange (ETDEWEB)

Woodhouse, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jones-Albertus, Rebecca [U.S. Dept. of Energy, Washington, DC (United States); Feldman, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Fu, Ran [National Renewable Energy Lab. (NREL), Golden, CO (United States); Horowitz, Kelsey [National Renewable Energy Lab. (NREL), Golden, CO (United States); Chung, Donald [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jordan, Dirk [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kurtz, Sarah [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-05-01

This report examines the remaining challenges to achieving the competitive photovoltaic (PV) costs and large-scale deployment envisioned under the U.S. Department of Energy's SunShot Initiative. Solar-energy cost reductions can be realized through lower PV module and balance-of-system (BOS) costs as well as improved system efficiency and reliability. Numerous combinations of PV improvements could help achieve the levelized cost of electricity (LCOE) goals because of the tradeoffs among key metrics like module price, efficiency, and degradation rate as well as system price and lifetime. Using LCOE modeling based on bottom-up cost analysis, two specific pathways are mapped to exemplify the many possible approaches to module cost reductions of 29%-38% between 2015 and 2020. BOS hardware and soft cost reductions, ranging from 54%-77% of total cost reductions, are also modeled. The residential sector's high supply-chain costs, labor requirements, and customer-acquisition costs give it the greatest BOS cost-reduction opportunities, followed by the commercial sector, although opportunities are available to the utility-scale sector as well. Finally, a future scenario is considered in which very high PV penetration requires additional costs to facilitate grid integration and increased power-system flexibility--which might necessitate even lower solar LCOEs. The analysis of a pathway to 3-5 cents/kWh PV systems underscores the importance of combining robust improvements in PV module and BOS costs as well as PV system efficiency and reliability if such aggressive long-term targets are to be achieved.

Achieving High Reliability with People, Processes, and Technology.

Science.gov (United States)

Saunders, Candice L; Brennan, John A

2017-01-01

High reliability as a corporate value in healthcare can be achieved by meeting the "Quadruple Aim" of improving population health, reducing per capita costs, enhancing the patient experience, and improving provider wellness. This drive starts with the board of trustees, CEO, and other senior leaders who ingrain high reliability throughout the organization. At WellStar Health System, the board developed an ambitious goal to become a top-decile health system in safety and quality metrics. To achieve this goal, WellStar has embarked on a journey toward high reliability and has committed to Lean management practices consistent with the Institute for Healthcare Improvement's definition of a high-reliability organization (HRO): one that is committed to the prevention of failure, early identification and mitigation of failure, and redesign of processes based on identifiable failures. In the end, a successful HRO can provide safe, effective, patient- and family-centered, timely, efficient, and equitable care through a convergence of people, processes, and technology.

75 FR 54591 - Notice of Agricultural Management Assistance Organic Certification Cost-Share Program

Science.gov (United States)

2010-09-08

...] Notice of Agricultural Management Assistance Organic Certification Cost-Share Program AGENCY... Agricultural Management Assistance Organic Certification Cost-Share Program. SUMMARY: This Notice invites the... Agreement with the Agricultural Marketing Service (AMS) for the Allocation of Organic Certification Cost...

77 FR 39858 - Revisions to Electric Reliability Organization Definition of Bulk Electric System and Rules of...

Science.gov (United States)

2012-07-05

... bulk electric system reliability through steady state power flow, and contain a transient stability... Commission 18 CFR Part 40 Revisions to Electric Reliability Organization Definition of Bulk Electric System... definition of ``bulk electric system'' developed by the North American Electric Reliability Corporation (NERC...

A cost-efficient and reliable energy management of a micro-grid using intelligent demand-response program

International Nuclear Information System (INIS)

Safamehr, Hossein; Rahimi-Kian, Ashkan

2015-01-01

Providing a cost-efficient and reliable energy is one of the main issues in human societies of the 21st century. In response to this demand, new features of micro grid technology have provided huge potentials, specifically by the capability of having an interactive coordination between energy suppliers and consumers. Accordingly, this paper offers an improved model for achieving an optimal Demand Response programing. To solve the proposed multi-objective optimization problem, Artificial Bee Colony algorithm and quasi-static technique are utilized. The considered objectives in this paper are minimizing the overall cost of energy consumption and also improving the technical parameters of micro grid over a time horizon. This optimization is subject to several constraints such as satisfying the energy balance and the operating constraints of each energy supply sources. Manageable load or load as source is another enabling feature existing in smart energy networks, which is considered in this paper and its effect on cost reduction and reliability improvement is studied. Trying to examine the performance of the proposed Demand Response Programing in real conditions, the uncertainties are also analyzed by stochastic methods. The results show significant improvements which are obtained by applying just intelligent programming and management. - Highlights: • This paper presents a cost-efficient and reliable energy management of a micro-grid. • New models of battery and manageable loads are formulated. • Artificial Bee Colony algorithm is used to solve the optimization problem. • Quasi-static technique is used to simplify the solving procedure. • The uncertainties are also analyzed by stochastic methods.

76 FR 23171 - Electric Reliability Organization Interpretations of Interconnection Reliability Operations and...

Science.gov (United States)

2011-04-26

... Reliability Standards for the Bulk-Power System, Order No. 693, FERC Stats. & Regs. ] 31,242, order on reh'g...-Power System reliability may request an interpretation of a Reliability Standard.\\7\\ The ERO's standards... information in its reliability assessments. The Reliability Coordinator must monitor Bulk Electric System...

A pilot study to explore the feasibility of using theClinical Care Classification System for developing a reliable costing method for nursing services.

Science.gov (United States)

Dykes, Patricia C; Wantland, Dean; Whittenburg, Luann; Lipsitz, Stuart; Saba, Virginia K

2013-01-01

While nursing activities represent a significant proportion of inpatient care, there are no reliable methods for determining nursing costs based on the actual services provided by the nursing staff. Capture of data to support accurate measurement and reporting on the cost of nursing services is fundamental to effective resource utilization. Adopting standard terminologies that support tracking both the quality and the cost of care could reduce the data entry burden on direct care providers. This pilot study evaluated the feasibility of using a standardized nursing terminology, the Clinical Care Classification System (CCC), for developing a reliable costing method for nursing services. Two different approaches are explored; the Relative Value Unit RVU and the simple cost-to-time methods. We found that the simple cost-to-time method was more accurate and more transparent in its derivation than the RVU method and may support a more consistent and reliable approach for costing nursing services.

Cross Cultural Perspectives of the Learning Organization: Assessing the Validity and Reliability of the DLOQ in Korea

Science.gov (United States)

Song, Ji Hoon; Kim, Jin Yong; Chermack, Thomas J.; Yang; Baiyin

2008-01-01

The primary purpose of this research was to adapt the Dimensions of Learning Organization Questionnaire (DLOQ) from Watkins and Marsick (1993, 1996) and examine its validity and reliability in a Korean context. Results indicate that the DLOQ produces valid and reliable scores of learning organization characteristics in a Korean cultural context.…

Equipment Reliability Program in NPP Krsko

International Nuclear Information System (INIS)

Skaler, F.; Djetelic, N.

2006-01-01

Operation that is safe, reliable, effective and acceptable to public is the common message in a mission statement of commercial nuclear power plants (NPPs). To fulfill these goals, nuclear industry, among other areas, has to focus on: 1 Human Performance (HU) and 2 Equipment Reliability (EQ). The performance objective of HU is as follows: The behaviors of all personnel result in safe and reliable station operation. While unwanted human behaviors in operations mostly result directly in the event, the behavior flaws either in the area of maintenance or engineering usually cause decreased equipment reliability. Unsatisfied Human performance leads even the best designed power plants into significant operating events, which can be found as well-known examples in nuclear industry. Equipment reliability is today recognized as the key to success. While the human performance at most NPPs has been improving since the start of WANO / INPO / IAEA evaluations, the open energy market has forced the nuclear plants to reduce production costs and operate more reliably and effectively. The balance between these two (opposite) goals has made equipment reliability even more important for safe, reliable and efficient production. Insisting on on-line operation by ignoring some principles of safety could nowadays in a well-developed safety culture and human performance environment exceed the cost of electricity losses. In last decade the leading USA nuclear companies put a lot of effort to improve equipment reliability primarily based on INPO Equipment Reliability Program AP-913 at their NPP stations. The Equipment Reliability Program is the key program not only for safe and reliable operation, but also for the Life Cycle Management and Aging Management on the way to the nuclear power plant life extension. The purpose of Equipment Reliability process is to identify, organize, integrate and coordinate equipment reliability activities (preventive and predictive maintenance, maintenance

Optimum capacity determination of stand-alone hybrid generation system considering cost and reliability

International Nuclear Information System (INIS)

Chen, Hung-Cheng

2013-01-01

Highlights: ► This paper presents a methodology for the installation capacity optimization. ► Hybrid generation system is optimized by application of adaptive genetic algorithm. ► A cost investigation is made under various conditions and component characteristics. ► The optimization scheme is validated to meet the annual power load demand. -- Abstract: The aim of this work is to present an optimization methodology for the installation capacity of a stand-alone hybrid generation system, taking into consideration the cost and reliability. Firstly, on the basis of derived steady state models of a wind generator (WG), a photovoltaic array (PV), a battery and an inverter, the hybrid generation system is modeled for the purpose of capacity optimization. Secondly, the power system is analyzed for determining both the system structure and the operation control strategy. Thirdly, according to hourly weather database of wind speed, temperature and solar irradiation, annual power generation capacity is estimated for the system match design in order that an annual power load demand can be met. The capacity determination of a hybrid generation system becomes complicated as a result of the uncertainty in the renewable energy together with load demand and the nonlinearity of system components. Aimed at the power system reliability and the cost minimization, the capacity of a hybrid generation system is optimized by application of an adaptive genetic algorithm (AGA) to individual power generation units. A total cost investigation is made under various conditions, such as wind generator power curves, battery discharge depth and the loss of load probability (LOLP). At the end of this work, the capacity of a hybrid generation system is optimized at two installation sites, namely the offshore Orchid Island and Wuchi in Taiwan. The optimization scheme is validated to optimize power capacities of a photovoltaic array, a battery and a wind turbine generator with a relative

Reliability-Based and Cost-Oriented Product Optimization Integrating Fuzzy Reasoning Petri Nets, Interval Expert Evaluation and Cultural-Based DMOPSO Using Crowding Distance Sorting

Directory of Open Access Journals (Sweden)

Zhaoxi Hong

2017-08-01

Full Text Available In reliability-based and cost-oriented product optimization, the target product reliability is apportioned to subsystems or components to achieve the maximum reliability and minimum cost. Main challenges to conducting such optimization design lie in how to simultaneously consider subsystem division, uncertain evaluation provided by experts for essential factors, and dynamic propagation of product failure. To overcome these problems, a reliability-based and cost-oriented product optimization method integrating fuzzy reasoning Petri net (FRPN, interval expert evaluation and cultural-based dynamic multi-objective particle swarm optimization (DMOPSO using crowding distance sorting is proposed in this paper. Subsystem division is performed based on failure decoupling, and then subsystem weights are calculated with FRPN reflecting dynamic and uncertain failure propagation, as well as interval expert evaluation considering six essential factors. A mathematical model of reliability-based and cost-oriented product optimization is established, and the cultural-based DMOPSO with crowding distance sorting is utilized to obtain the optimized design scheme. The efficiency and effectiveness of the proposed method are demonstrated by the numerical example of the optimization design for a computer numerically controlled (CNC machine tool.

Methodology of comprehensive evaluation of the effectiveness and reliability of production lines of preparation of sea water for the cultivation of aquatic organisms

Directory of Open Access Journals (Sweden)

S. D. Ugryumova

2016-01-01

Full Text Available The factors affecting the efficiency and reliability of technical systems. Set stages of development and modernization of production lines that correspond to specific stages of evaluating the effectiveness and reliability. Considered several methods of definition of indicators of indicators of efficiency and reliability of the equipment in technological lines of fisheries sector: forecasting methods, structural methods, physical methods, logical-probability method (method by I.A. Ryabinin and topological method. Advantages and disadvantages, allowing you to work out the most suitable method, process lines preparation of sea water for the cultivation of aquatic organisms, connected in series. Modernized technological line of preparation of sea water for the cultivation of aquatic organisms differing from the typical line of seawater in hatcheries (Far East, as the presence of a large number of instrumentation: sensors, salinity and temperature; motomeru that continuously monitor turbidity in the range of 50÷100 EMF (30÷60 mg/1 by kaolin; signaling the flow sensors volume level of the filtrate and the backfill layer; analyzers of chemical composition of sea water; analyzers of suspended mechanical impurities; signaling sensors of acidity and oxygen content and replacement filters coarse, fine cleaning and auxiliary equipment. A program of comprehensive evaluation of the effectiveness and reliability of production lines, revealed that conducted the modernization of production line preparation of sea water for the cultivation of aquatic organisms has improved its efficiency by an average of 1.71% to reduce the amount of manual labor by 15.1%; control the process; provide the most rapid, efficient purification of sea water; reduce the cost of replacement filter media.

Cost-Effectiveness of a Locally Organized Surgical Outreach Mission: Making a Case for Strengthening Local Non-Governmental Organizations.

Science.gov (United States)

Gyedu, Adam; Gaskill, Cameron; Boakye, Godfred; Abantanga, Francis

2017-12-01

Many low- and middle-income countries (LMICs) have a high prevalence of unmet surgical need. Provision of operations through surgical outreach missions, mostly led by foreign organizations, offers a way to address the problem. We sought to assess the cost-effectiveness of surgical outreach missions provided by a wholly local organization in Ghana to highlight the role local groups might play in reducing the unmet surgical need of their communities. We calculated the disability-adjusted life years (DALY) averted by surgical outreach mission activities of ApriDec Medical Outreach Group (AMOG), a Ghanaian non-governmental organization. The total cost of their activities was also calculated. Conclusions about cost-effectiveness were made according to World Health Organization (WHO)-suggested parameters. We analyzed 2008 patients who had been operated upon by AMOG since December 2011. Operations performed included hernia repairs (824 patients, 41%) and excision biopsy of soft tissue masses (364 patients, 18%). More specialized operations included thyroidectomy (103 patients, 5.1%), urological procedures (including prostatectomy) (71 patients, 3.5%), and plastic surgery (26 patients, 1.3%). Total cost of the outreach trips was $283,762, and 2079 DALY were averted; cost per DALY averted was 136.49 USD. The mission trips were "very cost-effective" per WHO parameters. There was a trend toward a lower cost per DALY averted with subsequent outreach trips organized by AMOG. Our findings suggest that providing surgical services through wholly local surgical mission trips to underserved LMIC communities might represent a cost-effective and viable option for countries seeking to reduce the growing unmet surgical needs of their populations.

78 FR 52131 - Notice of Funds Availability: Agricultural Management Assistance Organic Certification Cost-Share...

Science.gov (United States)

2013-08-22

...] Notice of Funds Availability: Agricultural Management Assistance Organic Certification Cost-Share Program... . SUPPLEMENTARY INFORMATION: This Organic Certification Cost-Share Program is part of the Agricultural Management... Wyoming. The AMS has allocated $1,352,850 for this organic certification cost- share program in Fiscal...

Investment in new product reliability

International Nuclear Information System (INIS)

Murthy, D.N.P.; Rausand, M.; Virtanen, S.

2009-01-01

Product reliability is of great importance to both manufacturers and customers. Building reliability into a new product is costly, but the consequences of inadequate product reliability can be costlier. This implies that manufacturers need to decide on the optimal investment in new product reliability by achieving a suitable trade-off between the two costs. This paper develops a framework and proposes an approach to help manufacturers decide on the investment in new product reliability.

A Highly Reliable and Cost-Efficient Multi-Sensor System for Land Vehicle Positioning

Directory of Open Access Journals (Sweden)

Xu Li

2016-05-01

Full Text Available In this paper, we propose a novel positioning solution for land vehicles which is highly reliable and cost-efficient. The proposed positioning system fuses information from the MEMS-based reduced inertial sensor system (RISS which consists of one vertical gyroscope and two horizontal accelerometers, low-cost GPS, and supplementary sensors and sources. First, pitch and roll angle are accurately estimated based on a vehicle kinematic model. Meanwhile, the negative effect of the uncertain nonlinear drift of MEMS inertial sensors is eliminated by an H∞ filter. Further, a distributed-dual-H∞ filtering (DDHF mechanism is adopted to address the uncertain nonlinear drift of the MEMS-RISS and make full use of the supplementary sensors and sources. The DDHF is composed of a main H∞ filter (MHF and an auxiliary H∞ filter (AHF. Finally, a generalized regression neural network (GRNN module with good approximation capability is specially designed for the MEMS-RISS. A hybrid methodology which combines the GRNN module and the AHF is utilized to compensate for RISS position errors during GPS outages. To verify the effectiveness of the proposed solution, road-test experiments with various scenarios were performed. The experimental results illustrate that the proposed system can achieve accurate and reliable positioning for land vehicles.

Activity – based costing in sport organizations:Theoretical background & future prospects

Directory of Open Access Journals (Sweden)

PANAGIOTIS E. DIMITROPOULOS

2007-01-01

Full Text Available Costing systems in recent years have shown a significantdevelopment and activity-based costing (ABC specificallyhas been considered as a major contribution to cost management, particularly in service businesses. The sport sector is composed to a great extent of service functions, yet considerably less have been reported of the use of activity based costing to support cost management in sport organizations. Since the power of information becomes continuously crucial for the implementation of effective business administration, the traditional methods of cost measurementproved insufficient on this issue, leading to the invention ofABC. The aim of this paper is twofold. First of all we wantto present the main theoretical background of ABC and itssubstantiated benefits, and secondly to present some practical steps for the implementation of ABC in sport organizations.

77 FR 59745 - Delegation of Authority Regarding Electric Reliability Organization's Budget, Delegation...

Science.gov (United States)

2012-10-01

...; Order No. 766] Delegation of Authority Regarding Electric Reliability Organization's Budget, Delegation... rule. SUMMARY: The Commission is issuing this Final Rule to revise its delegations of authority to... delegation agreements, and ERO policies and procedures. DATES: This rule is effective October 1, 2012. FOR...

A dynamic simulation model for assessing the overall impact of incentive policies on power system reliability, costs and environment

International Nuclear Information System (INIS)

Ibanez-Lopez, A.S.; Martinez-Val, J.M.; Moratilla-Soria, B.Y.

2017-01-01

The liberalization of power markets has entailed dramatic changes in power system planning worldwide. The inception of new alternative technologies, smart grids and distributed generation and storage is expected to make system planning even more challenging. Government policies still play a major role in the evolution of a country's power generation mix, even in those countries with liberalized markets. This paper presents a System Dynamics model aimed at assessing the overall technical, economic and environmental impact of renewable energy incentives and capacity payment policies. The model has been used to simulate Spain's power industry in order to assess the impact of electric power policies with the goal of getting insights regarding how to achieve an optimum power generation mix. The main conclusions of the present paper are (i) the necessity of specific regulatory actions in Spain in order to keep adequate reliability levels, avoid price spikes and boom and bust investment cycles as well as to deploy specific technologies, (ii) the fact that capacity payments are a better instrument for keeping adequate reserve margins and avoiding power price spikes than renewable energy incentives and (iii) the evidence that both instruments entail additional system costs over the base case scenario. - Highlights: • A System Dynamics model of Spain's power generation mix is proposed. • The overall policy impact on system costs, environment and reliability is assessed. • Current policies are not enough to keep adequate reliability levels. • Capacity payments are an adequate instrument for guaranteeing system reliability. • RES incentives do not solve reliability issues and entail greater system costs.

Development of geological disposal system; localization of element cost data and cost evaluation on the HLW repository

Energy Technology Data Exchange (ETDEWEB)

Lee, Byung Sik; Kim, Kil Jung; Yang, Young Jin; Kim, Sung Chun [KOPEC, Taejeon (Korea)

2002-03-01

To estimate Total Life Cycle Cost (TSLCC) for Korea HLW Repository through localization of element cost data, we review and re-organize each basic element cost data for reference repository system, localize various element cost and finally estimate TSLCC considering economic parameters. As results of the study, TSLCC is estimated as 17,167,689 million won, which includes costs for site preparation, surface facilities, underground facilities and management/integration. Since HLW repository Project is an early stage of pre-conceptual design at present, the information of design and project information are not enough to perform cost estimate and cost localization for the Project. However, project cost structure is re-organized based on the local condition and Total System Life Cycle Cost is estimated using the previous cost data gathered from construction experience of the local nuclear power plant. Project results can be used as basic reference data to assume total construction cost for the local HLW repository and should be revised to more reliable cost data with incorporating detail project design information into the cost estimate in a future. 20 refs. (Author)

Cost effective tools for soil organic carbon monitoring

Science.gov (United States)

Shepherd, Keith; Aynekulu, Ermias

2013-04-01

There is increasing demand for data on soil properties at fine spatial resolution to support management and planning decisions. Measurement of soil organic carbon has attracted much interest because (i) soil organic carbon is widely cited as a useful indicator of soil condition and (ii) of the importance of soil carbon in the global carbon cycle and climate mitigation strategies. However in considering soil measurement designs there has been insufficient attention given to careful analysis of the specific decisions that the measurements are meant to support and on what measurements have high information value for decision-making. As a result, much measurement effort may be wasted or focused on the wrong variables. A cost-effective measurement is one that reduces risk in decisions and does not cost more than the societal returns to additional evidence. A key uncertainty in measuring soil carbon as a soil condition indicator is what constitutes a good or bad level of carbon on a given soil. A measure of soil organic carbon concentration may have limited value for informing management decisions without the additional information required to interpret it, and so expending further efforts on improving measurements to increase precision may then have no value to improving the decision. Measuring soil carbon stock changes for carbon trading purposes requires high levels of measurement precision but there is still large uncertainty on whether the costs of measurement exceed the benefits. Since the largest cost component in soil monitoring is often travel to the field and physically sampling soils, it is generally cost-effective to meet multiple objectives by analysing a number of properties on a soil sample. Diffuse reflectance infrared spectroscopy is playing a key role in allowing multiple soil properties to be determined rapidly and at low cost. The method provides estimation of multiple soil properties (e.g. soil carbon, texture and mineralogy) in one measurement

[Financing, organization, costs and services performance of the Argentinean health sub-systems.

Science.gov (United States)

Yavich, Natalia; Báscolo, Ernesto Pablo; Haggerty, Jeannie

2016-01-01

To analyze the relationship between health system financing and services organization models with costs and health services performance in each of Rosario's health sub-systems. The financing and organization models were characterized using secondary data. Costs were calculated using the WHO/SHA methodology. Healthcare quality was measured by a household survey (n=822). Public subsystem:Vertically integrated funding and primary healthcare as a leading strategy to provide services produced low costs and individual-oriented healthcare but with weak accessibility conditions and comprehensiveness. Private subsystem: Contractual integration and weak regulatory and coordination mechanisms produced effects opposed to those of the public sub-system. Social security: Contractual integration and strong regulatory and coordination mechanisms contributed to intermediate costs and overall high performance. Each subsystem financing and services organization model had a strong and heterogeneous influence on costs and health services performance.

Reliability of a patient survey assessing cost-related changes in health care use among high deductible health plan enrollees

Directory of Open Access Journals (Sweden)

Galbraith Alison A

2011-05-01

Full Text Available Abstract Background Recent increases in patient cost-sharing for health care have lent increasing importance to monitoring cost-related changes in health care use. Despite the widespread use of survey questions to measure changes in health care use and related behaviors, scant data exists on the reliability of such questions. Methods We administered a cross-sectional survey to a stratified random sample of families in a New England health plan's high deductible health plan (HDHP with ≥ $500 in annualized out-of-pocket expenditures. Enrollees were asked about their knowledge of their plan, information seeking, behavior change associated with having a deductible, experience of delay in care due in part to cost, and hypothetical delay in care due in part to cost. Initial respondents were mailed a follow-up survey within two weeks of each family returning the original survey. We computed several agreement statistics to measure the test-retest reliability for select questions. We also conducted continuity adjusted chi-square, and McNemar tests in both the original and follow-up samples to measure the degree to which our results could be reproduced. Analyses were stratified by self-reported income. Results The test-retest reliability was moderate for the majority of questions (0.41 - 0.60 and the level of test-retest reliability did not differ substantially across each of the broader domains of questions. The observed proportions of respondents with delayed or foregone pediatric, adult, or any family care were similar when comparing the original and follow-up surveys. In the original survey, respondents in the lower-income group were more likely to delay or forego pediatric care, adult care, or any family care. All of the tests comparing income groups in the follow-up survey produced the same result as in the original survey. Conclusions In this population of HDHP beneficiaries, we found that survey questions concerning plan knowledge, information

Reliable sagittal plane kinematic gait assessments are feasible using low-cost webcam technology.

Science.gov (United States)

Saner, Robert J; Washabaugh, Edward P; Krishnan, Chandramouli

2017-07-01

Three-dimensional (3-D) motion capture systems are commonly used for gait analysis because they provide reliable and accurate measurements. However, the downside of this approach is that it is expensive and requires technical expertise; thus making it less feasible in the clinic. To address this limitation, we recently developed and validated (using a high-precision walking robot) a low-cost, two-dimensional (2-D) real-time motion tracking approach using a simple webcam and LabVIEW Vision Assistant. The purpose of this study was to establish the repeatability and minimal detectable change values of hip and knee sagittal plane gait kinematics recorded using this system. Twenty-one healthy subjects underwent two kinematic assessments while walking on a treadmill at a range of gait velocities. Intraclass correlation coefficients (ICC) and minimal detectable change (MDC) values were calculated for commonly used hip and knee kinematic parameters to demonstrate the reliability of the system. Additionally, Bland-Altman plots were generated to examine the agreement between the measurements recorded on two different days. The system demonstrated good to excellent reliability (ICC>0.75) for all the gait parameters tested on this study. The MDC values were typically low (gait assessments using webcam technology can be reliably used for clinical and research purposes. Copyright © 2017 Elsevier B.V. All rights reserved.

Compliance and High Reliability in a Complex Healthcare Organization.

Science.gov (United States)

Simon, Maxine dellaBadia

2018-01-01

When considering the impact of regulation on healthcare, visualize a spider's web. The spider weaves sections together to create the whole, with each fiber adding to the structure to support its success or lead to its failure. Each section is dependent on the others, and all must be aligned to maintain the structure. Outside forces can cause a shift in the web's fragile equilibrium.The interdependence of the sections of the spider's web is similar to the way hospital departments and services work together. An organization's structure must be shaped to support its mission and vision. At the same time, the business of healthcare requires the development and achievement of operational objectives and financial performance goals. Establishing a culture that is flexible enough to permit creativity, provide resiliency, and manage complexity as the organization grows is fundamental to success. An organization must address each of these factors while maintaining stability, carrying out its mission, and fostering improvement.Nature's order maintains the spider's web. Likewise, regulation can strengthen healthcare organizations by initiating disruptive changes that can support efforts to achieve and sustain high reliability in the delivery of care. To that end, leadership must be willing to provide the necessary vision and resources.

Applying Organization Theory to Understanding the Adoption and Implementation of Accountable Care Organizations: Commentary.

Science.gov (United States)

Shortell, Stephen M

2016-12-01

This commentary highights the key arguments and contributions of institutional thoery, transaction cost economics (TCE) theory, high reliability theory, and organizational learning theory to understanding the development and evolution of Accountable Care Organizations (ACOs). Institutional theory and TCE theory primarily emphasize the external influences shaping ACOs while high reliability theory and organizational learning theory underscore the internal fctors influencing ACO perfromance. A framework based on Implementation Science is proposed to conside the multiple perspectives on ACOs and, in particular, their abiity to innovate to achieve desired cost, quality, and population health goals. © The Author(s) 2016.

COST/BENEFIT ANALYSIS – A TOOL TO IMPROVE RECRUITMENT, SELECTION AND EMPLOYMENT IN ORGANIZATIONS

Directory of Open Access Journals (Sweden)

Nicoleta Valentina FLOREA

2013-11-01

Full Text Available Human resource is a major source for organization to obtain competitive advantage and can be very important in obtaining long-term performance. The limits of recruitment process are the cost, the choice made, time and legislation. Any organization looks for minimizing the human resources recruitment, selection and employment costs. This article presents the importance of cost in choosing the best practices of recruitment, selection, employment and integration of new employees in the organization, though, the cost is an important variable for analysis. In this article is presented the research made in large organizations from Dambovita County, Romania, and are also presented the costs and their consequences on medium and long-term over the organization activities These activities are discrimination, sexual harassment, ethics, low performance and results, by choosing the “wrong” people, and implicitly diminishing the level of qualifications, knowledge and abilities, by growing the absenteeism, the direct and indirect costs of these processes and the direct consequences over the time management.

PV Systems Reliability Final Technical Report.

Energy Technology Data Exchange (ETDEWEB)

Lavrova, Olga [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Flicker, Jack David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Johnson, Jay [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Armijo, Kenneth Miguel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gonzalez, Sigifredo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Schindelholz, Eric John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sorensen, Neil R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Yang, Benjamin Bing-Yeh [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-12-01

The continued exponential growth of photovoltaic technologies paves a path to a solar-powered world, but requires continued progress toward low-cost, high-reliability, high-performance photovoltaic (PV) systems. High reliability is an essential element in achieving low-cost solar electricity by reducing operation and maintenance (O&M) costs and extending system lifetime and availability, but these attributes are difficult to verify at the time of installation. Utilities, financiers, homeowners, and planners are demanding this information in order to evaluate their financial risk as a prerequisite to large investments. Reliability research and development (R&D) is needed to build market confidence by improving product reliability and by improving predictions of system availability, O&M cost, and lifetime. This project is focused on understanding, predicting, and improving the reliability of PV systems. The two areas being pursued include PV arc-fault and ground fault issues, and inverter reliability.

A standard for test reliability in group research.

Science.gov (United States)

Ellis, Jules L

2013-03-01

Many authors adhere to the rule that test reliabilities should be at least .70 or .80 in group research. This article introduces a new standard according to which reliabilities can be evaluated. This standard is based on the costs or time of the experiment and of administering the test. For example, if test administration costs are 7 % of the total experimental costs, the efficient value of the reliability is .93. If the actual reliability of a test is equal to this efficient reliability, the test size maximizes the statistical power of the experiment, given the costs. As a standard in experimental research, it is proposed that the reliability of the dependent variable be close to the efficient reliability. Adhering to this standard will enhance the statistical power and reduce the costs of experiments.

Power electronics reliability analysis.

Energy Technology Data Exchange (ETDEWEB)

Smith, Mark A.; Atcitty, Stanley

2009-12-01

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.

Reliability Modeling of Wind Turbines

DEFF Research Database (Denmark)

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...... 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...... to one third of the total cost of energy. Reduction of Operation & Maintenance costs will result in significant cost savings and result in cheaper electricity production. Operation & Maintenance processes mainly involve actions related to replacements or repair. Identifying the right times when...

Patient safety in anesthesia: learning from the culture of high-reliability organizations.

Science.gov (United States)

Wright, Suzanne M

2015-03-01

There has been an increased awareness of and interest in patient safety and improved outcomes, as well as a growing body of evidence substantiating medical error as a leading cause of death and injury in the United States. According to The Joint Commission, US hospitals demonstrate improvements in health care quality and patient safety. Although this progress is encouraging, much room for improvement remains. High-reliability organizations, industries that deliver reliable performances in the face of complex working environments, can serve as models of safety for our health care system until plausible explanations for patient harm are better understood. Copyright © 2015 Elsevier Inc. All rights reserved.

Evaluation of a proposal for reliable low-cost grid power with 100% wind, water, and solar.

Science.gov (United States)

Clack, Christopher T M; Qvist, Staffan A; Apt, Jay; Bazilian, Morgan; Brandt, Adam R; Caldeira, Ken; Davis, Steven J; Diakov, Victor; Handschy, Mark A; Hines, Paul D H; Jaramillo, Paulina; Kammen, Daniel M; Long, Jane C S; Morgan, M Granger; Reed, Adam; Sivaram, Varun; Sweeney, James; Tynan, George R; Victor, David G; Weyant, John P; Whitacre, Jay F

2017-06-27

A number of analyses, meta-analyses, and assessments, including those performed by the Intergovernmental Panel on Climate Change, the National Oceanic and Atmospheric Administration, the National Renewable Energy Laboratory, and the International Energy Agency, have concluded that deployment of a diverse portfolio of clean energy technologies makes a transition to a low-carbon-emission energy system both more feasible and less costly than other pathways. In contrast, Jacobson et al. [Jacobson MZ, Delucchi MA, Cameron MA, Frew BA (2015) Proc Natl Acad Sci USA 112(49):15060-15065] argue that it is feasible to provide "low-cost solutions to the grid reliability problem with 100% penetration of WWS [wind, water and solar power] across all energy sectors in the continental United States between 2050 and 2055", with only electricity and hydrogen as energy carriers. In this paper, we evaluate that study and find significant shortcomings in the analysis. In particular, we point out that this work used invalid modeling tools, contained modeling errors, and made implausible and inadequately supported assumptions. Policy makers should treat with caution any visions of a rapid, reliable, and low-cost transition to entire energy systems that relies almost exclusively on wind, solar, and hydroelectric power.

Reliability in automotive and mechanical engineering determination of component and system reliability

CERN Document Server

Bertsche, Bernd

2008-01-01

In the present contemporary climate of global competition in every branch of engineering and manufacture it has been shown from extensive customer surveys that above every other attribute, reliability stands as the most desired feature in a finished product. To survive this relentless fight for survival any organisation, which neglect the plea of attaining to excellence in reliability, will do so at a serious cost Reliability in Automotive and Mechanical Engineering draws together a wide spectrum of diverse and relevant applications and analyses on reliability engineering. This is distilled into this attractive and well documented volume and practising engineers are challenged with the formidable task of simultaneously improving reliability and reducing the costs and down-time due to maintenance. The volume brings together eleven chapters to highlight the importance of the interrelated reliability and maintenance disciplines. They represent the development trends and progress resulting in making this book ess...

Mission Reliability Estimation for Repairable Robot Teams

Science.gov (United States)

Trebi-Ollennu, Ashitey; Dolan, John; Stancliff, Stephen

2010-01-01

A mission reliability estimation method has been designed to translate mission requirements into choices of robot modules in order to configure a multi-robot team to have high reliability at minimal cost. In order to build cost-effective robot teams for long-term missions, one must be able to compare alternative design paradigms in a principled way by comparing the reliability of different robot models and robot team configurations. Core modules have been created including: a probabilistic module with reliability-cost characteristics, a method for combining the characteristics of multiple modules to determine an overall reliability-cost characteristic, and a method for the generation of legitimate module combinations based on mission specifications and the selection of the best of the resulting combinations from a cost-reliability standpoint. The developed methodology can be used to predict the probability of a mission being completed, given information about the components used to build the robots, as well as information about the mission tasks. In the research for this innovation, sample robot missions were examined and compared to the performance of robot teams with different numbers of robots and different numbers of spare components. Data that a mission designer would need was factored in, such as whether it would be better to have a spare robot versus an equivalent number of spare parts, or if mission cost can be reduced while maintaining reliability using spares. This analytical model was applied to an example robot mission, examining the cost-reliability tradeoffs among different team configurations. Particularly scrutinized were teams using either redundancy (spare robots) or repairability (spare components). Using conservative estimates of the cost-reliability relationship, results show that it is possible to significantly reduce the cost of a robotic mission by using cheaper, lower-reliability components and providing spares. This suggests that the

A practical approach for calculating reliable cost estimates from observational data: application to cost analyses in maternal and child health.

Science.gov (United States)

Salemi, Jason L; Comins, Meg M; Chandler, Kristen; Mogos, Mulubrhan F; Salihu, Hamisu M

2013-08-01

Comparative effectiveness research (CER) and cost-effectiveness analysis are valuable tools for informing health policy and clinical care decisions. Despite the increased availability of rich observational databases with economic measures, few researchers have the skills needed to conduct valid and reliable cost analyses for CER. The objectives of this paper are to (i) describe a practical approach for calculating cost estimates from hospital charges in discharge data using publicly available hospital cost reports, and (ii) assess the impact of using different methods for cost estimation in maternal and child health (MCH) studies by conducting economic analyses on gestational diabetes (GDM) and pre-pregnancy overweight/obesity. In Florida, we have constructed a clinically enhanced, longitudinal, encounter-level MCH database covering over 2.3 million infants (and their mothers) born alive from 1998 to 2009. Using this as a template, we describe a detailed methodology to use publicly available data to calculate hospital-wide and department-specific cost-to-charge ratios (CCRs), link them to the master database, and convert reported hospital charges to refined cost estimates. We then conduct an economic analysis as a case study on women by GDM and pre-pregnancy body mass index (BMI) status to compare the impact of using different methods on cost estimation. Over 60 % of inpatient charges for birth hospitalizations came from the nursery/labor/delivery units, which have very different cost-to-charge markups (CCR = 0.70) than the commonly substituted hospital average (CCR = 0.29). Using estimated mean, per-person maternal hospitalization costs for women with GDM as an example, unadjusted charges ($US14,696) grossly overestimated actual cost, compared with hospital-wide ($US3,498) and department-level ($US4,986) CCR adjustments. However, the refined cost estimation method, although more accurate, did not alter our conclusions that infant/maternal hospitalization costs

An alternative to the balance error scoring system: using a low-cost balance board to improve the validity/reliability of sports-related concussion balance testing.

Science.gov (United States)

Chang, Jasper O; Levy, Susan S; Seay, Seth W; Goble, Daniel J

2014-05-01

Recent guidelines advocate sports medicine professionals to use balance tests to assess sensorimotor status in the management of concussions. The present study sought to determine whether a low-cost balance board could provide a valid, reliable, and objective means of performing this balance testing. Criterion validity testing relative to a gold standard and 7 day test-retest reliability. University biomechanics laboratory. Thirty healthy young adults. Balance ability was assessed on 2 days separated by 1 week using (1) a gold standard measure (ie, scientific grade force plate), (2) a low-cost Nintendo Wii Balance Board (WBB), and (3) the Balance Error Scoring System (BESS). Validity of the WBB center of pressure path length and BESS scores were determined relative to the force plate data. Test-retest reliability was established based on intraclass correlation coefficients. Composite scores for the WBB had excellent validity (r = 0.99) and test-retest reliability (R = 0.88). Both the validity (r = 0.10-0.52) and test-retest reliability (r = 0.61-0.78) were lower for the BESS. These findings demonstrate that a low-cost balance board can provide improved balance testing accuracy/reliability compared with the BESS. This approach provides a potentially more valid/reliable, yet affordable, means of assessing sports-related concussion compared with current methods.

Problems in diagnosing and forecasting power equipment reliability

Energy Technology Data Exchange (ETDEWEB)

Popkov, V I; Demirchyan, K S

1979-11-01

This general survey deals with approaches to the resolution of such problems as the gathering, analysis and systematization of data on component defects in power equipment and setting up feedback with the manufacturing plants and planning organizations to improve equipment reliability. Such efforts on the part of designers, manufacturers and operating and repair organizations in analyzing faults in 300 MW turbogenerators during 1974-1977 reduced the specific fault rate by 20 to 25% and the downtime per failure by 35 to 40%. Since power equipment should operate for several hundreds of thousands of hours (20 to 30 years) and the majority of power components have guaranteed service lives of no more than 10/sup 5/ hours, an extremely difficult problem is the determination of the reliability of equipment past the 10/sup 5/ point. The present trend in the USSR Unified Power System towards increasing the number of shutdowns and startups, which in the case of turbogenerators of up 1200 MW power can reach 7500 to 10,000 cycles is noted. Other areas briefly treated are: MHD generator reliability and economy; nuclear power plant reliability and safety; the reliability of high-power high-voltage thyristor converters; the difficulties involved in scale modeling of power system reliability and the high cost of the requisite full-scale studies; the poor understanding of long term corrosion and erosion processes. The review concludes with arguments in favor of greater computerization of all aspects of power system management.

A reliable, fast and low cost maximum power point tracker for photovoltaic applications

Energy Technology Data Exchange (ETDEWEB)

Enrique, J.M.; Andujar, J.M.; Bohorquez, M.A. [Departamento de Ingenieria Electronica, de Sistemas Informaticos y Automatica, Universidad de Huelva (Spain)

2010-01-15

This work presents a new maximum power point tracker system for photovoltaic applications. The developed system is an analog version of the ''P and O-oriented'' algorithm. It maintains its main advantages: simplicity, reliability and easy practical implementation, and avoids its main disadvantages: inaccurateness and relatively slow response. Additionally, the developed system can be implemented in a practical way at a low cost, which means an added value. The system also shows an excellent behavior for very fast variables in incident radiation levels. (author)

Strength and Reliability of Wood for the Components of Low-cost Wind Turbines: Computational and Experimental Analysis and Applications

DEFF Research Database (Denmark)

Mishnaevsky, Leon; Freere, Peter; Sharma, Ranjan

2009-01-01

of experiments and computational investigations. Low cost testing machines have been designed, and employed for the systematic analysis of different sorts of Nepali wood, to be used for the wind turbine construction. At the same time, computational micromechanical models of deformation and strength of wood......This paper reports the latest results of the comprehensive program of experimental and computational analysis of strength and reliability of wooden parts of low cost wind turbines. The possibilities of prediction of strength and reliability of different types of wood are studied in the series...... are developed, which should provide the basis for microstructure-based correlating of observable and service properties of wood. Some correlations between microstructure, strength and service properties of wood have been established....

Towards low cost, efficient and stable organic photovoltaic modules

Energy Technology Data Exchange (ETDEWEB)

Andriessen, R. [Holst Centre - Solliance, PO Box 8550, 5605 KN Eindhoven (Netherlands); Kroon, J.M. [ECN - Solliance, Petten (Netherlands); Aernouts, T. [Imec, Solliance, Kapeldreef 75, B-3001 Leuven (Belgium); Janssen, R. [Eindhoven University of Technology, Solliance, Eindhoven (Netherlands)

2012-09-15

This article describes how the Solliance Organic PhotoVoltaics (OPV) shared research Program addresses efficiency, lifetime and production costs for (near) future OPV applications. The balance of these three parameters depends of the envisaged application, but at the end, OPV should be able to compete somehow with Si PV in the future. Efficiency improvements are realized by developing new materials, by exploring and optimizing new device structures and novel interconnection technologies. Lifetime improvements are realized by using stabilized device stacks and materials and by applying high end flexible barriers. Production cost control is done by using a home made Cost of Ownership tool which guides towards the use of low-cost materials and processes.

78 FR 38851 - Electric Reliability Organization Proposal To Retire Requirements in Reliability Standards

Science.gov (United States)

2013-06-28

... either: Provide little protection for Bulk-Power System reliability or are redundant with other aspects... for retirement either: (1) Provide little protection for Bulk-Power System reliability or (2) are... to assure reliability of the Bulk-Power System and should be withdrawn. We have identified 41...

Impact cost of the product on the effectiveness of business organizations

Directory of Open Access Journals (Sweden)

A. S. Senin

2015-01-01

Full Text Available One of the key elements of managing the operations of the organization - management costs, as the costs, representing the payment that needs to be done to attract and retain economic resources, are one of the main factors determining the size of the financial results of the organization, return on invested capital, and, ultimately, the value of the business.Objectives. The aim of this work is to study the influence of the structure of production costs on the profitability of products.Method’s. To complete this article were used such methods of analysis as legal, comparative, economic-statistical and correlation.Conclusions / significance. The practical value of this work lies in the fact that in the article the notion and cogs, equations of linear regression between the proportion of costs in the cost and profitability of products by types of economic activity in the Russian Federation in 2012, the Obtained models allow knowing the share of costs in the cost structure for different types of economic activities in the Russian Federation in 2012 to estimate the average level of profitability of production.

A cost modelling system for cloud computing

OpenAIRE

Ajeh, Daniel; Ellman, Jeremy; Keogh, Shelagh

2014-01-01

An advance in technology unlocks new opportunities for organizations to increase their productivity, efficiency and process automation while reducing the cost of doing business as well. The emergence of cloud computing addresses these prospects through the provision of agile systems that are scalable, flexible and reliable as well as cost effective. Cloud computing has made hosting and deployment of computing resources cheaper and easier with no up-front charges but pay per-use flexible payme...

Cost-effective solutions to maintaining smart grid reliability

Science.gov (United States)

Qin, Qiu

As the aging power systems are increasingly working closer to the capacity and thermal limits, maintaining an sufficient reliability has been of great concern to the government agency, utility companies and users. This dissertation focuses on improving the reliability of transmission and distribution systems. Based on the wide area measurements, multiple model algorithms are developed to diagnose transmission line three-phase short to ground faults in the presence of protection misoperations. The multiple model algorithms utilize the electric network dynamics to provide prompt and reliable diagnosis outcomes. Computational complexity of the diagnosis algorithm is reduced by using a two-step heuristic. The multiple model algorithm is incorporated into a hybrid simulation framework, which consist of both continuous state simulation and discrete event simulation, to study the operation of transmission systems. With hybrid simulation, line switching strategy for enhancing the tolerance to protection misoperations is studied based on the concept of security index, which involves the faulted mode probability and stability coverage. Local measurements are used to track the generator state and faulty mode probabilities are calculated in the multiple model algorithms. FACTS devices are considered as controllers for the transmission system. The placement of FACTS devices into power systems is investigated with a criterion of maintaining a prescribed level of control reconfigurability. Control reconfigurability measures the small signal combined controllability and observability of a power system with an additional requirement on fault tolerance. For the distribution systems, a hierarchical framework, including a high level recloser allocation scheme and a low level recloser placement scheme, is presented. The impacts of recloser placement on the reliability indices is analyzed. Evaluation of reliability indices in the placement process is carried out via discrete event

Planning Costs in Certain Stage of the Life Cycle of Investment Activity of Construction Organization

Directory of Open Access Journals (Sweden)

Iakymchuk Iryna M.

2017-09-01

Full Text Available The article discusses the issues related to planning costs in certain stages of the life-cycle of investment activity of construction organization. It has been specified that cost management based on the life-cycle model of the investment project, which is being implemented by a construction organization, allows for a consistent improvement in the efficiency of the innovation process on the basis of a clear planning, as well as cost forecasting. This approach allows for the long-term effectiveness of innovation project by providing cost-management services at all stages of investment project, identifying opportunities for reducing them, thereby contributing to sustainable development of construction organization over time. It has been concluded that the more specific the program of activities of construction organization, the more accurate the process of identification of costs becomes, the more efficient is the management of costs, targeted at saving resources, reducing the self cost of construction works.

18 CFR 39.3 - Electric Reliability Organization certification.

Science.gov (United States)

2010-04-01

... operators of the Bulk-Power System, and other interested parties for improvement of the Electric Reliability... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Electric Reliability..., Reliability Standards that provide for an adequate level of reliability of the Bulk-Power System, and (2) Has...

How to Prepare an Indirect Cost Rate Proposal for a Non-profit Organization

Science.gov (United States)

The indirect cost rate proposal is the documentation prepared by a grantee organization, in accordance with applicable federal cost principles, to substantiate its claim for the reimbursement of indirect costs.

[Employees in high-reliability organizations: systematic selection of personnel as a final criterion].

Science.gov (United States)

Oubaid, V; Anheuser, P

2014-05-01

Employees represent an important safety factor in high-reliability organizations. The combination of clear organizational structures, a nonpunitive safety culture, and psychological personnel selection guarantee a high level of safety. The cockpit personnel selection process of a major German airline is presented in order to demonstrate a possible transferability into medicine and urology.

Reliability Assessment Of Wind Turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2014-01-01

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...

Hawaii Electric System Reliability

Energy Technology Data Exchange (ETDEWEB)

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)

2012-08-01

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.

Reliable cost effective technique for in situ ground stress measurements in deep gold mines.

CSIR Research Space (South Africa)

Stacey, TR

1995-07-01

Full Text Available on these requirements, an in situ stress measurement technique which will be practically applicable in the deep gold mines, has been developed conceptually. Referring to the figure on the following page, this method involves: • a borehole-based system, using... level mines have not been developed. 2 This is some of the background to the present SIMRAC research project, the title ofwhich is “Reliable cost effective technique for in-situ ground stress measurements in deep gold mines”. A copy of the research...

Improving machinery reliability

CERN Document Server

Bloch, Heinz P

1998-01-01

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.

Reliability training

Science.gov (United States)

Lalli, Vincent R. (Editor); Malec, Henry A. (Editor); Dillard, Richard B.; Wong, Kam L.; Barber, Frank J.; Barina, Frank J.

1992-01-01

Discussed here is failure physics, the study of how products, hardware, software, and systems fail and what can be done about it. The intent is to impart useful information, to extend the limits of production capability, and to assist in achieving low cost reliable products. A review of reliability for the years 1940 to 2000 is given. Next, a review of mathematics is given as well as a description of what elements contribute to product failures. Basic reliability theory and the disciplines that allow us to control and eliminate failures are elucidated.

Innovating Without Information Constraints: Organizations, Communities, and Innovation When Information Costs Approach Zero

OpenAIRE

Elizabeth J. Altman; Frank Nagle; Michael L. Tushman

2013-01-01

Innovation traditionally takes place within an organization's boundaries and with selected partners. This Chandlerian approach is rooted in transaction costs, organizational boundaries, and information challenges. Information processing, storage, and communication costs have been an important constraint on innovation and a reason why innovation takes place inside the organization. However, exponential technological progress is dramatically decreasing information constraints, and in many conte...

More reliable financing of future nuclear waste costs

International Nuclear Information System (INIS)

1994-01-01

A commission of inquiry was established by Government in 1993 to review the management of capital funds according to the existing Act of the Financing of Future Expenses for Spent Nuclear Fuel etc. The commission proposes that: The funds which have been paid to the Swedish state to finance the costs arising in connection with the handling and final disposal of spent nuclear fuel etc, from the year 1995, should be invested in accordance with guidelines which aim at attaining a higher return than is currently possible; That an independent government body, called the Nuclear Waste Fund, should be assigned the task of managing the funds, in accordance with these guidelines; That the Swedish Nuclear Power Inspectorate should continue to examine and evaluate issues relating to the application of the funds and recommend the level of the fee to be paid; and That a system including additional measures for guaranteeing the availability of funds should be implemented from the year 1995, in order to improve the reliability of the financing system. Our proposal involves extensive amendments to the Financing Act. On the other hand, the basic stipulations concerning responsibilities under the Act on Nuclear Activities, are not affected. (Seven work documents produced by consulting firms are published in a separate volume; SOU 1994:108) 5 figs., 16 tabs

Reliability-based optimization of engineering structures

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2008-01-01

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...... problems are generalized to the following extensions: interactive optimization, inspection and repair costs, systematic reconstruction, re-assessment of existing structures. Illustrative examples are presented including a simple introductory example, a decision problem related to bridge re...

Hawaii electric system reliability.

Energy Technology Data Exchange (ETDEWEB)

Silva Monroy, Cesar Augusto; Loose, Verne William

2012-09-01

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.

Process-based costing.

Science.gov (United States)

Lee, Robert H; Bott, Marjorie J; Forbes, Sarah; Redford, Linda; Swagerty, Daniel L; Taunton, Roma Lee

2003-01-01

Understanding how quality improvement affects costs is important. Unfortunately, low-cost, reliable ways of measuring direct costs are scarce. This article builds on the principles of process improvement to develop a costing strategy that meets both criteria. Process-based costing has 4 steps: developing a flowchart, estimating resource use, valuing resources, and calculating direct costs. To illustrate the technique, this article uses it to cost the care planning process in 3 long-term care facilities. We conclude that process-based costing is easy to implement; generates reliable, valid data; and allows nursing managers to assess the costs of new or modified processes.

Influence of ITO patterning on reliability of organic light emitting devices

International Nuclear Information System (INIS)

Wang, Zhaokui; Naka, Shigeki; Okada, Hiroyuki

2009-01-01

Indium tin oxide (ITO) films are widely used for a transparent electrode of organic light emitting devices (OLEDs) because of its excellent conductivity and transparency. Two types of ITO substrates with different surface roughness were selected to use as anode of OLEDs. In addition, two types of etching process of ITO substrate, particularly the etching time, were also carried out. It was found that the surface roughness and/or the etching process of ITO substrate strongly influenced on an edge of ITO surface, further affected the operating characteristics and reliability of devices.

Cost Engineering Techniques and Their Applicability for Cost Estimation of Organic Rankine Cycle Systems

Directory of Open Access Journals (Sweden)

Sanne Lemmens

2016-06-01

Full Text Available The potential of organic Rankine cycle (ORC systems is acknowledged by both considerable research and development efforts and an increasing number of applications. Most research aims at improving ORC systems through technical performance optimization of various cycle architectures and working fluids. The assessment and optimization of technical feasibility is at the core of ORC development. Nonetheless, economic feasibility is often decisive when it comes down to considering practical instalments, and therefore an increasing number of publications include an estimate of the costs of the designed ORC system. Various methods are used to estimate ORC costs but the resulting values are rarely discussed with respect to accuracy and validity. The aim of this paper is to provide insight into the methods used to estimate these costs and open the discussion about the interpretation of these results. A review of cost engineering practices shows there has been a long tradition of industrial cost estimation. Several techniques have been developed, but the expected accuracy range of the best techniques used in research varies between 10% and 30%. The quality of the estimates could be improved by establishing up-to-date correlations for the ORC industry in particular. Secondly, the rapidly growing ORC cost literature is briefly reviewed. A graph summarizing the estimated ORC investment costs displays a pattern of decreasing costs for increasing power output. Knowledge on the actual costs of real ORC modules and projects remains scarce. Finally, the investment costs of a known heat recovery ORC system are discussed and the methodologies and accuracies of several approaches are demonstrated using this case as benchmark. The best results are obtained with factorial estimation techniques such as the module costing technique, but the accuracies may diverge by up to +30%. Development of correlations and multiplication factors for ORC technology in particular is

A reliable low-cost wireless and wearable gait monitoring system based on a plastic optical fibre sensor

International Nuclear Information System (INIS)

Bilro, L; Pinto, J L; Oliveira, J G; Nogueira, R N

2011-01-01

A wearable and wireless system designed to evaluate quantitatively the human gait is presented. It allows knee sagittal motion monitoring over long distances and periods with a portable and low-cost package. It is based on the measurement of transmittance changes when a side-polished plastic optical fibre is bent. Four voluntary healthy subjects, on five different days, were tested in order to assess inter-day and inter-subject reliability. Results have shown that this technique is reliable, allows a one-time calibration and is suitable in the diagnosis and rehabilitation of knee injuries or for monitoring the performance of competitive athletes. Environmental testing was accomplished in order to study the influence of different temperatures and humidity conditions

Evaluation of the Influence of the Logistic Operations Reliability on the Total Costs of a Supply Chain

Directory of Open Access Journals (Sweden)

Lukinskiy Valery

2016-12-01

Full Text Available Nowadays in logistics integral processes between the material and related flows in supply chains are getting developed more and more. However, in spite of increasing volume of statistical data which reflect the integral processes, the influence evaluation issues of the logistic operations reliability indexes on the total logistics costs remain open and require the corresponding researches implementation.

Risk-based Optimization and Reliability Levels of Coastal Structures

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Burcharth, H. F.

Identification of optimum reliability levels for coastal structures is considered. A class of breakwaters is considered where no human injuries can be expected in cases of failure. The optimum reliability level is identified by minimizing the total costs over the service life of the structure, in...... on the minimumcost reliability levels is investigated for different values of the real rate of interest, the service lifetime, the downtime costs due to malfunction and the decommission costs.......Identification of optimum reliability levels for coastal structures is considered. A class of breakwaters is considered where no human injuries can be expected in cases of failure. The optimum reliability level is identified by minimizing the total costs over the service life of the structure...

Risk-based Optimization and Reliability Levels of Coastal Structures

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Burcharth, Hans F.

2005-01-01

 Identification of optimum reliability levels for coastal structures is considered. A class of breakwaters is considered where no human injuries can be expected in cases of failure. The optimum reliability level is identified by minimizing the total costs over the service life of the structure, i...... on the minimumcost reliability levels is investigated for different values of the real rate of interest, the service lifetime, the downtime costs due to malfunction and the decommission costs....... Identification of optimum reliability levels for coastal structures is considered. A class of breakwaters is considered where no human injuries can be expected in cases of failure. The optimum reliability level is identified by minimizing the total costs over the service life of the structure...

2017 NREL Photovoltaic Reliability Workshop

Energy Technology Data Exchange (ETDEWEB)

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

2017-08-15

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.

Understanding organic photovoltaic cells: Electrode, nanostructure, reliability, and performance

Science.gov (United States)

Kim, Myung-Su

My Ph.D. research has focused on alternative renewable energy using organic semiconductors. During my study, first, I have established reliable characterization methods of organic photovoltaic devices. More specifically, less than 5% variation of power conversion efficiency of fabricated organic blend photovoltaic cells (OBPC) was achieved after optimization. The reproducibility of organic photovoltaic cell performance is one of the essential issues that must be clarified before beginning serious investigations of the application of creative and challenging ideas. Second, the relationships between fill factor (FF) and process variables have been demonstrated with series and shunt resistance, and this provided a chance to understand the electrical device behavior. In the blend layer, series resistance (Rs) and shunt resistance (Rsh) were varied by controlling the morphology of the blend layer, the regioregularity of the conjugated polymer, and the thickness of the blend layer. At the interface between the cathode including PEDOT:PSS and the blend layer, cathode conductivity was controlled by varying the structure of the cathode or adding an additive. Third, we thoroughly examined possible characterization mistakes in OPVC. One significant characterization mistake is observed when the crossbar electrode geometry of OPVC using PEDOT:PSS was fabricated and characterized with illumination which is larger than the actual device area. The hypothesis to explain this overestimation was excess photo-current generated from the cell region outside the overlapped electrode area, where PEDOT:PSS plays as anode and this was clearly supported with investigations. Finally, I incorporated a creative idea, which enhances the exciton dissociation efficiency by increasing the interface area between donor and acceptor to improve the power conversion efficiency of organic photovoltaic cells. To achieve this, nanoimprint lithography was applied for interface area increase. To clarify the

Optimal number of tests to achieve and validate product reliability

International Nuclear Information System (INIS)

Ahmed, Hussam; Chateauneuf, Alaa

2014-01-01

The reliability validation of engineering products and systems is mandatory for choosing the best cost-effective design among a series of alternatives. Decisions at early design stages have a large effect on the overall life cycle performance and cost of products. In this paper, an optimization-based formulation is proposed by coupling the costs of product design and validation testing, in order to ensure the product reliability with the minimum number of tests. This formulation addresses the question about the number of tests to be specified through reliability demonstration necessary to validate the product under appropriate confidence level. The proposed formulation takes into account the product cost, the failure cost and the testing cost. The optimization problem can be considered as a decision making system according to the hierarchy of structural reliability measures. The numerical examples show the interest of coupling design and testing parameters. - Highlights: • Coupled formulation for design and testing costs, with lifetime degradation. • Cost-effective testing optimization to achieve reliability target. • Solution procedure for nested aleatoric and epistemic variable spaces

Reliability assessment of Wind turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2015-01-01

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...

Structural reliability codes for probabilistic design

DEFF Research Database (Denmark)

Ditlevsen, Ove Dalager

1997-01-01

probabilistic code format has not only strong influence on the formal reliability measure, but also on the formal cost of failure to be associated if a design made to the target reliability level is considered to be optimal. In fact, the formal cost of failure can be different by several orders of size for two...... different, but by and large equally justifiable probabilistic code formats. Thus, the consequence is that a code format based on decision theoretical concepts and formulated as an extension of a probabilistic code format must specify formal values to be used as costs of failure. A principle of prudence...... is suggested for guiding the choice of the reference probabilistic code format for constant reliability. In the author's opinion there is an urgent need for establishing a standard probabilistic reliability code. This paper presents some considerations that may be debatable, but nevertheless point...

The Long-Term Effectiveness and Cost Effectiveness of Organized versus Opportunistic Screening for Breast Cancer in Austria.

Science.gov (United States)

Schiller-Fruehwirth, Irmgard; Jahn, Beate; Einzinger, Patrick; Zauner, Günther; Urach, Christoph; Siebert, Uwe

2017-09-01

In 2014, Austrian health authorities implemented an organized breast cancer screening program. Until then, there has been a long-standing tradition of opportunistic screening. To evaluate the cost-effectiveness of organized screening compared with opportunistic screening, as well as to identify factors influencing the clinical and economic outcomes. We developed and validated an individual-level state-transition model and assessed the health outcomes and costs of organized and opportunistic screening for 40-year-old asymptomatic women. The base-case analysis compared a scenario involving organized biennial screening with a scenario reflecting opportunistic screening practice for an average-risk woman aged 45 to 69 years. We applied an annual discount rate of 3% and estimated the incremental cost-effectiveness ratio in terms of the cost (2012 euros) per life-year gained (LYG) from a health care perspective. Deterministic and probabilistic sensitivity analyses were performed to assess uncertainty. Compared with opportunistic screening, an organized program yielded on average additional 0.0118 undiscounted life-years (i.e., 4.3 days) and cost savings of €41 per woman. In the base-case analysis, the incremental cost-effectiveness ratio of organized screening was approximately €20,000 per LYG compared with no screening. Assuming a willingness-to-pay threshold of €50,000 per LYG, there was a 70% probability that organized screening would be considered cost-effective. The attendance rate, but not the test accuracy of mammography, was an influential factor for the cost-effectiveness. The decision to adopt organized screening is likely an efficient use of limited health care resources in Austria. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

PV O&M Cost Model and Cost Reduction

Energy Technology Data Exchange (ETDEWEB)

Walker, Andy

2017-03-15

This is a presentation on PV O&M cost model and cost reduction for the annual Photovoltaic Reliability Workshop (2017), covering estimating PV O&M costs, polynomial expansion, and implementation of Net Present Value (NPV) and reserve account in cost models.

Cost analysis of surgical treatment for pelvic organ prolapse by laparoscopic sacrocolpopexy or transvaginal mesh.

Science.gov (United States)

Carracedo, D; López-Fando, L; Sánchez, M D; Jiménez, M Á; Gómez, J M; Laso, I; Rodríguez, M Á; Burgos, F J

2017-03-01

The objective of this study is to compare direct costs of repairing pelvic organ prolapse by laparoscopic sacrocolpopexy (LS) against vaginal mesh (VM). Our hypothesis is the correction of pelvic organ prolapse by LS has a similar cost per procedure compared to VM. We made a retrospective comparative analysis of medium cost per procedure of first 69 consecutive LS versus first 69 consecutive VM surgeries. We calculate direct cost for each procedure: structural outlays, personal, operating room occupation, hospital stay, perishable or inventory material and prosthetic material. Medium cost per procedure were calculated for each group, with a 95% confidence interval. LS group has a higher cost related to a longer length of surgery, higher operating room occupation and anesthesia; VM group has a higher cost due to longer hospital stay and more expensive prosthetic material. Globally, LS has a lower medium cost per procedure in comparison to VM (5,985.7 €±1,550.8 € vs. 6,534.3 €±1,015.5 €), although it did not achieve statistical signification. In our midst, pelvic organ prolapse surgical correction by LS has at least similar cost per procedure compared to VM. Copyright © 2016 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

Composite reliability evaluation for transmission network planning

Directory of Open Access Journals (Sweden)

Jiashen Teh

2018-01-01

Full Text Available As the penetration of wind power into the power system increases, the ability to assess the reliability impact of such interaction becomes more important. The composite reliability evaluations involving wind energy provide ample opportunities for assessing the benefits of different wind farm connection points. A connection to the weak area of the transmission network will require network reinforcement for absorbing the additional wind energy. Traditionally, the reinforcements are performed by constructing new transmission corridors. However, a new state-of-art technology such as the dynamic thermal rating (DTR system, provides new reinforcement strategy and this requires new reliability assessment method. This paper demonstrates a methodology for assessing the cost and the reliability of network reinforcement strategies by considering the DTR systems when large scale wind farms are connected to the existing power network. Sequential Monte Carlo simulations were performed and all DTRs and wind speed were simulated using the auto-regressive moving average (ARMA model. Various reinforcement strategies were assessed from their cost and reliability aspects. Practical industrial standards are used as guidelines when assessing costs. Due to this, the proposed methodology in this paper is able to determine the optimal reinforcement strategies when both the cost and reliability requirements are considered.

Application of customer-interruption costs for optimum distribution planning

International Nuclear Information System (INIS)

Mok, Y.L.; Chung, T.S.

1996-01-01

We present a new methodology for obtaining optimum values of the integrated cost of utility investment with customer interruption in distribution planning for electric power systems by determining the reliability cost and worth of the distribution system. Reliability cost refers to investment cost of the utility in achieving a defined level of reliability. Reliability worth is the benefit gained by the utility customer from an increase of reliability. A computer program has been developed to determine comparative reliability indices for a typical distribution network. With the average interruption cost, outage duration, average disconnected load, cost data for distribution equipment, etc. being known, the relation between reliability cost, reliability worth and reliability at the specified load point are obtained. The optimum reliability of the distribution system is then determined from the minimum cost to the utility with customer interruption. The applicability of this approach is demonstrated by several practical networks. (Author)

[Skin cancer screening and treatment costs : Utilisation of the skin cancer screening and skin cancer treatment costs in organ transplant recipients].

Science.gov (United States)

Jäckel, D; Schlothauer, N I; Zeeb, H; Wagner, G; Sachse, M M

2018-04-12

Organ transplant recipients have an up to 250-times higher risk to develop skin cancer. This article evaluated the utilisation of skin cancer screening and the treatment costs for skin cancer in organ transplant recipients. Patients of the health insurance AOK Bremen/Bremerhaven had been identified and the need for skin cancer prevention trainings was derived. The number of organ transplant recipients (ICD code Z94.0-4) with and without any history of skin cancer (ICD code C43/C44), the utilisation of dermatologic health care services, and the costs for treatments with the diagnosis Z94.0-4 with and without C43/C44 were evaluated. The analyses were carried out for the period from 2009-2014 by using the accounting systems of the AOK. Between 2009 and 2014, 231 organ transplant recipients had been recorded. By mid-2014, 20% of these insured persons developed skin cancer and the mean incidence was 2.76% per year. On average, 43% of these patients were seen by a dermatologist at least once a year, whereby only 15% of the organ transplant recipients participated in the annual skin cancer screening. In 29% of the patients without any history of skin cancer, a skin examination was never performed by a dermatologist or a general practitioner. In all, 17 inpatient cases of organ transplant recipients with the primary diagnosis C43/C44 were analyzed. This resulted in total costs of 54,707 € (on average about 3200 € per case). The increased incidence of skin cancer and the associated treatment costs indicate the need for skin cancer prevention training.

A Cost-Effective Two-Part Experiment for Teaching Introductory Organic Chemistry Techniques

Science.gov (United States)

Sadek, Christopher M.; Brown, Brenna A.; Wan, Hayley

2011-01-01

This two-part laboratory experiment is designed to be a cost-effective method for teaching basic organic laboratory techniques (recrystallization, thin-layer chromatography, column chromatography, vacuum filtration, and melting point determination) to large classes of introductory organic chemistry students. Students are exposed to different…

Reliability and validity of the German version of the Structured Interview of Personality Organization (STIPO)

Science.gov (United States)

2013-01-01

Background The assessment of personality organization and its observable behavioral manifestations, i.e. personality functioning, has a long tradition in psychodynamic psychiatry. Recently, the DSM-5 Levels of Personality Functioning Scale has moved it into the focus of psychiatric diagnostics. Based on Kernberg’s concept of personality organization the Structured Interview of Personality Organization (STIPO) was developed for diagnosing personality functioning. The STIPO covers seven dimensions: (1) identity, (2) object relations, (3) primitive defenses, (4) coping/rigidity, (5) aggression, (6) moral values, and (7) reality testing and perceptual distortions. The English version of the STIPO has previously revealed satisfying psychometric properties. Methods Validity and reliability of the German version of the 100-item instrument have been evaluated in 122 psychiatric patients. All patients were diagnosed according to the Diagnostic and Statistical Manual for Mental Disorders (DSM-IV) and were assessed by means of the STIPO. Moreover, all patients completed eight questionnaires that served as criteria for external validity of the STIPO. Results Interrater reliability varied between intraclass correlations of .89 and 1.0, Crohnbach’s α for the seven dimensions was .69 to .93. All a priori selected questionnaire scales correlated significantly with the corresponding STIPO dimensions. Patients with personality disorder (PD) revealed significantly higher STIPO scores (i.e. worse personality functioning) than patients without PD; patients cluster B PD showed significantly higher STIPO scores than patients with cluster C PD. Conclusions Interrater reliability, Crohnbach’s α, concurrent validity, and differential validity of the STIPO are satisfying. The STIPO represents an appropriate instrument for the assessment of personality functioning in clinical and research settings. PMID:23941404

Planning Costs in Certain Stage of the Life Cycle of Investment Activity of Construction Organization

OpenAIRE

Iakymchuk Iryna M.

2017-01-01

The article discusses the issues related to planning costs in certain stages of the life-cycle of investment activity of construction organization. It has been specified that cost management based on the life-cycle model of the investment project, which is being implemented by a construction organization, allows for a consistent improvement in the efficiency of the innovation process on the basis of a clear planning, as well as cost forecasting. This approach allows for the long-term effectiv...

The Stability and Reliability of a Modified Work Components Study Questionnaire in the Educational Organization.

Science.gov (United States)

Miskel, Cecil; Heller, Leonard E.

The investigation attempted to establish the factorial validity and reliability of an industrial selection device based on Herzberg's theory of work motivation related to the school organization. The questionnaire was reworded to reflect an educational work situation; and a random sample of 197 students, 118 administrators, and 432 teachers was…

More reliable financing of future nuclear waste costs

International Nuclear Information System (INIS)

1994-01-01

This appendix contains seven reports written by consultants to the Commission. The report titles are: Basic document regarding the inquiry on fund management; Scenarios for growth and real interest rates in a long perspective; Stability of the Swedish financing system; Report concerning the financing of nuclear waste management in Sweden and Finland and the cost control system in Sweden; Evaluation of the cost estimates and calculation methods of SKB; A study of the costs for nuclear waste - The basis for cost estimation; A review of scope and costs for the Swedish system for management of nuclear waste. The four last reports are separately indexed

NDE performance demonstration in the US nuclear power industry - applications, costs, lessons learned, and connection to NDE reliability

International Nuclear Information System (INIS)

Ammirato, F.

1997-01-01

Periodic inservice inspection (ISI) of nuclear power plant components is performed in the United States to satisfy legal commitments and to provide plant owners with reliable information for managing degradation. Performance demonstration provides credible evidence that ISI will fulfill its objectives. This paper examines the technical requirements for inspection and discusses how these technical needs are used to develop effective performance demonstration applications. NDE reliability is discussed with particular reference to its role in structural integrity assessments and its connection with performance demonstration. It is shown that the role of NDE reliability can range from very small to critical depending on the particular application and must be considered carefully in design of inspection techniques and performance demonstration programs used to qualify the inspection. Finally, the costs, benefits, and problems associated with performance demonstration are reviewed along with lessons learned from more than 15 years of performance demonstration experience in the US. (orig.)

Optimal design of a system containing mixed redundancies with respect to reliability and cost

International Nuclear Information System (INIS)

Misra, K.B.

1975-01-01

A nuclear system generally consists of subsystems that may employ any of the partial, standby, and active redundancies, and is, therefore, a system with mixed type of redundancies. Optimization of reliability or availability of such systems at the design stage is a difficult problem. There appears to be no published work on the optimal design of maintained systems consisting of mixed redundancies. An attempt is therefore made, to present the basis of design and the solution technique to achieve this. An algorithm is described which makes the solution of this mathematically difficult problem possible. Some examples are demonstrated. To achieve further efficiency a study was organized and the recommendations for obtaining a minimum solution time are provided. Although, in the illustration, only the linear constraints and reliability, as the only design parameter, have been considered, the algorithm works well with the nonlinear type of constraints and can be used with other design parameters also. (author)

Hybrids - Best of both worlds. [liquid and solid propellants mated for safe reliable and low cost launch vehicles

Science.gov (United States)

Goldberg, Ben E.; Wiley, Dan R.

1991-01-01

An overview is presented of hybrid rocket propulsion systems whereby combining solids and liquids for launch vehicles could produce a safe, reliable, and low-cost product. The primary subsystems of a hybrid system consist of the oxidizer tank and feed system, an injector system, a solid fuel grain enclosed in a pressure vessel case, a mixing chamber, and a nozzle. The hybrid rocket has an inert grain, which reduces costs of development, transportation, manufacturing, and launch by avoiding many safety measures that must be taken when operating with solids. Other than their use in launch vehicles, hybrids are excellent for simulating the exhaust of solid rocket motors for material development.

On Cost Estimate for Decommissioning of one Isotope Central

International Nuclear Information System (INIS)

Marek Vasko et al

2010-08-01

The main scope of this study has been to calculate the future cost for decommission and dismantling the Isotope central at the Studsvik site using the OMEGA CODE. Detailed empirical information is used in the study for 'bench-marking' purposes, in such cases when there is a need to supplement and correct field data from the industry. In the present study, data has been retrieved and organized such that the estimated costs for decommissioning of the Isotope Central become transparent and reliable. This approach gives a preliminary qualitative indication about the accuracy of the cost estimate delivered by the industry

On Cost Estimate for Decommissioning of one Isotope Central

Energy Technology Data Exchange (ETDEWEB)

Marek Vasko et al

2010-08-15

The main scope of this study has been to calculate the future cost for decommission and dismantling the Isotope central at the Studsvik site using the OMEGA CODE. Detailed empirical information is used in the study for 'bench-marking' purposes, in such cases when there is a need to supplement and correct field data from the industry. In the present study, data has been retrieved and organized such that the estimated costs for decommissioning of the Isotope Central become transparent and reliable. This approach gives a preliminary qualitative indication about the accuracy of the cost estimate delivered by the industry

Design and implementation of a reliable and cost-effective cloud computing infrastructure: the INFN Napoli experience

International Nuclear Information System (INIS)

Capone, V; Esposito, R; Pardi, S; Taurino, F; Tortone, G

2012-01-01

Over the last few years we have seen an increasing number of services and applications needed to manage and maintain cloud computing facilities. This is particularly true for computing in high energy physics, which often requires complex configurations and distributed infrastructures. In this scenario a cost effective rationalization and consolidation strategy is the key to success in terms of scalability and reliability. In this work we describe an IaaS (Infrastructure as a Service) cloud computing system, with high availability and redundancy features, which is currently in production at INFN-Naples and ATLAS Tier-2 data centre. The main goal we intended to achieve was a simplified method to manage our computing resources and deliver reliable user services, reusing existing hardware without incurring heavy costs. A combined usage of virtualization and clustering technologies allowed us to consolidate our services on a small number of physical machines, reducing electric power costs. As a result of our efforts we developed a complete solution for data and computing centres that can be easily replicated using commodity hardware. Our architecture consists of 2 main subsystems: a clustered storage solution, built on top of disk servers running GlusterFS file system, and a virtual machines execution environment. GlusterFS is a network file system able to perform parallel writes on multiple disk servers, providing this way live replication of data. High availability is also achieved via a network configuration using redundant switches and multiple paths between hypervisor hosts and disk servers. We also developed a set of management scripts to easily perform basic system administration tasks such as automatic deployment of new virtual machines, adaptive scheduling of virtual machines on hypervisor hosts, live migration and automated restart in case of hypervisor failures.

Design and implementation of a reliable and cost-effective cloud computing infrastructure: the INFN Napoli experience

Science.gov (United States)

Capone, V.; Esposito, R.; Pardi, S.; Taurino, F.; Tortone, G.

2012-12-01

Over the last few years we have seen an increasing number of services and applications needed to manage and maintain cloud computing facilities. This is particularly true for computing in high energy physics, which often requires complex configurations and distributed infrastructures. In this scenario a cost effective rationalization and consolidation strategy is the key to success in terms of scalability and reliability. In this work we describe an IaaS (Infrastructure as a Service) cloud computing system, with high availability and redundancy features, which is currently in production at INFN-Naples and ATLAS Tier-2 data centre. The main goal we intended to achieve was a simplified method to manage our computing resources and deliver reliable user services, reusing existing hardware without incurring heavy costs. A combined usage of virtualization and clustering technologies allowed us to consolidate our services on a small number of physical machines, reducing electric power costs. As a result of our efforts we developed a complete solution for data and computing centres that can be easily replicated using commodity hardware. Our architecture consists of 2 main subsystems: a clustered storage solution, built on top of disk servers running GlusterFS file system, and a virtual machines execution environment. GlusterFS is a network file system able to perform parallel writes on multiple disk servers, providing this way live replication of data. High availability is also achieved via a network configuration using redundant switches and multiple paths between hypervisor hosts and disk servers. We also developed a set of management scripts to easily perform basic system administration tasks such as automatic deployment of new virtual machines, adaptive scheduling of virtual machines on hypervisor hosts, live migration and automated restart in case of hypervisor failures.

Providing all global energy with wind, water, and solar power, Part II: Reliability, system and transmission costs, and policies

International Nuclear Information System (INIS)

Delucchi, Mark A.; Jacobson, Mark Z.

2011-01-01

This is Part II of two papers evaluating the feasibility of providing all energy for all purposes (electric power, transportation, and heating/cooling), everywhere in the world, from wind, water, and the sun (WWS). In Part I, we described the prominent renewable energy plans that have been proposed and discussed the characteristics of WWS energy systems, the global demand for and availability of WWS energy, quantities and areas required for WWS infrastructure, and supplies of critical materials. Here, we discuss methods of addressing the variability of WWS energy to ensure that power supply reliably matches demand (including interconnecting geographically dispersed resources, using hydroelectricity, using demand-response management, storing electric power on site, over-sizing peak generation capacity and producing hydrogen with the excess, storing electric power in vehicle batteries, and forecasting weather to project energy supplies), the economics of WWS generation and transmission, the economics of WWS use in transportation, and policy measures needed to enhance the viability of a WWS system. We find that the cost of energy in a 100% WWS will be similar to the cost today. We conclude that barriers to a 100% conversion to WWS power worldwide are primarily social and political, not technological or even economic. - Research highlights: → We evaluate the feasibility of global energy supply from wind, water, and solar energy. → WWS energy can be supplied reliably and economically to all energy-use sectors. → The social cost of WWS energy generally is less than the cost of fossil-fuel energy. → Barriers to 100% WWS power worldwide are socio-political, not techno-economic.

A study of low-cost reliable actuators for light aircraft. Part A: Chapters 1-8

Science.gov (United States)

Eijsink, H.; Rice, M.

1978-01-01

An analysis involving electro-mechanical, electro-pneumatic, and electro-hydraulic actuators was performed to study which are compatible for use in the primary and secondary flight controls of a single engine light aircraft. Actuator characteristics under investigation include cost, reliability, weight, force, volumetric requirements, power requirements, response characteristics and heat accumulation characteristics. The basic types of actuators were compared for performance characteristics in positioning a control surface model and then were mathematically evaluated in an aircraft to get the closed loop dynamic response characteristics. Conclusions were made as to the suitability of each actuator type for use in an aircraft.

Comparison of Quantity Versus Quality Using Performance, Reliability, and Life Cycle Cost Data. A Case Study of the F-15, F-16, and A-10 Aircraft.

Science.gov (United States)

1985-09-01

CoC S~04 COMPARISON OF QUANTITY VERSUS QUALITY USING PERFORMANCE, RELIABILITY, AND LIFE CYCLE COST DATA. A CASE STUDY OF THE F-15, F-16, AND A-10...CYCLE COSTIATU.AT CAE AIR ORE HEO OG .- jAITR UIVERSITY W right.,Patterson Air Force Base, Ohio .! 5ൔ ,6 198 C.IT. U AF’IT/GSL,4/L3Q/65:S Ŗ J...COMPARISON OF QUANTITY VERSUS QUALITY USING PERFORMANCE, RELIABILITY, AND LIFE CYCLE COST DATA. A CASE STUDY OF THE F-15, F-16, AND A-10 AIRCRAFT THESIS David

TFTR CAMAC power supplies reliability

International Nuclear Information System (INIS)

Camp, R.A.; Bergin, W.

1989-01-01

Since the expected life of the Tokamak Fusion Test Reactor (TFTR) has been extended into the early 1990's, the issues of equipment wear-out, when to refurbish/replace, and the costs associated with these decisions, must be faced. The management of the maintenance of the TFTR Central Instrumentation, Control and Data Acquisition System (CICADA) power supplies within the CAMAC network is a case study of a set of systems to monitor repairable systems reliability, costs, and results of action. The CAMAC network is composed of approximately 500 racks, each with its own power supply. By using a simple reliability estimator on a coarse time interval, in conjunction with determining the root cause of individual failures, a cost effective repair and maintenance program has been realized. This paper describes the estimator, some of the specific causes for recurring failures and their correction, and the subsequent effects on the reliability estimator. By extension of this program the authors can assess the continued viability of CAMAC power supplies into the future, predicting wear-out and developing cost effective refurbishment/replacement policies. 4 refs., 3 figs., 1 tab

Assessing the contribution of microgrids to the reliability of distribution networks

Energy Technology Data Exchange (ETDEWEB)

Costa, Paulo Moises [Escola Superior Tecnologia Viseu, Instituto Politecnico Viseu, Campus Politecnico Repeses, 3504-510 Viseu (Portugal); Matos, Manuel A. [INESC Porto, Faculdade de Engenharia da Universidade do Porto, Porto (Portugal)

2009-02-15

The emergence of microgeneration has recently lead to the concept of microgrid, a network of LV consumers and producers able to export electric energy in some circumstances and also to work in an isolated way in emergency situations. Research on the organization of microgrids, control devices, functionalities and other technical aspects is presently being carried out, in order to establish a consistent technical framework to support the concept. The successful development of the microgrid concept implies the definition of a suitable regulation for its integration on distribution systems. In order to define such a regulation, the identification of costs and benefits that microgrids may bring is a crucial task. Actually, this is the basis for a discussion about the way global costs could be divided among the different agents that benefit from the development of microgrids. Among other aspects, the effect of microgrids on the reliability of the distribution network has been pointed out as an important advantage, due to the ability of isolated operation in emergency situations. This paper identifies the situations where the existence of a microgrid may reduce the interruption rate and duration and thus improve the reliability indices of the distribution network. The relevant expressions necessary to quantify the reliability are presented. An illustrative example is included, where the global influence of the microgrid in the reliability is commented. (author)

18 CFR 39.5 - Reliability Standards.

Science.gov (United States)

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Reliability Standards... RELIABILITY STANDARDS § 39.5 Reliability Standards. (a) The Electric Reliability Organization shall file each Reliability Standard or modification to a Reliability Standard that it proposes to be made effective under...

The Centralized Reliability Data Organization (CREDO); an advanced nuclear reactor reliability, availability, and maintainability data bank and data analysis center

International Nuclear Information System (INIS)

Knee, H.E.

1991-01-01

The Centralized Reliability Data Organization (CREDO) is a data bank and data analysis center, which since 1985 has been jointly sponsored by the US Department of Energy's (US DOE's) Office of Technology Support Programs and Japan's Power Reactor and Nuclear Fuel Development Corporation (PNC). It focuses on reliability, availability and maintainability (RAM) data for components (e.g. valves, pumps, etc.) operating in advanced nuclear reactor facilities. As originally intended, the purpose of the CREDO system was to provide a centralized source of accurate, up-to-date data and information for use in RAM analyses necessary for meeting DOE's data needs in the areas of advanced reactor safety assessments, design and licensing. In particular, creation of the CREDO system was considered an essential element needed to fulfill the DOE Breeder Reactor Safety Program's commitment of 'identifying and exploiting areas in which probabilistic methods can be developed and used in making reactor safety Research and Development choices and optimizing designs of safety systems'. CREDO and its operation are explained. (author)

Integrated reliability condition monitoring and maintenance of equipment

CERN Document Server

Osarenren, John

2015-01-01

Consider a Viable and Cost-Effective Platform for the Industries of the Future (IOF) Benefit from improved safety, performance, and product deliveries to your customers. Achieve a higher rate of equipment availability, performance, product quality, and reliability. Integrated Reliability: Condition Monitoring and Maintenance of Equipment incorporates reliable engineering and mathematical modeling to help you move toward sustainable development in reliability condition monitoring and maintenance. This text introduces a cost-effective integrated reliability growth monitor, integrated reliability degradation monitor, technological inheritance coefficient sensors, and a maintenance tool that supplies real-time information for predicting and preventing potential failures of manufacturing processes and equipment. The author highlights five key elements that are essential to any improvement program: improving overall equipment and part effectiveness, quality, and reliability; improving process performance with maint...

Interaction of CREDO [Centralized Reliability Data Organization] with the EBR-II [Experimental Breeder Reactor II] PRA [probabilistic risk assessment] development

International Nuclear Information System (INIS)

Smith, M.S.; Ragland, W.A.

1989-01-01

The National Academy of Sciences review of US Department of Energy (DOE) class 1 reactors recommended that the Experimental Breeder Reactor II (EBR-II), operated by Argonne National Laboratory (ANL), develop a level 1 probabilistic risk assessment (PRA) and make provisions for level 2 and level 3 PRAs based on the results of the level 1 PRA. The PRA analysis group at ANL will utilize the Centralized Reliability Data Organization (CREDO) at Oak Ridge National Laboratory to support the PRA data needs. CREDO contains many years of empirical liquid-metal reactor component data from EBR-II. CREDO is a mutual data- and cost-sharing system sponsored by DOE and the Power Reactor and Nuclear Fuels Development Corporation of Japan. CREDO is a component based data system; data are collected on components that are liquid-metal specific, associated with a liquid-metal environment, contained in systems that interface with liquid-metal environments, or are safety related for use in reliability/availability/maintainability (RAM) analyses of advanced reactors. The links between the EBR-II PRA development effort and the CREDO data collection at EBR-II extend beyond the sharing of data. The PRA provides a measure of the relative contribution to risk of the various components. This information can be used to prioritize future CREDO data collection activities at EBR-II and other sites

In-plant application of industry experience to enhance human reliability

International Nuclear Information System (INIS)

Hannaman, G.W.; Singh, A.

1993-01-01

This paper describes the way that modern data-base computer tools can enhance the ability to collect, organize, evaluate, and use industry experience. By combining the computer tools with knowledge from human reliability assessment tools, data, and frameworks, the data base can become a tool for collecting and assessing the lessons learned from past events. By integrating the data-base system with plant risk models, engineers can focus on those activities that can enhance over-all system reliability. The evaluation helps identify technology and tools to reduce human errors during operations and maintenance. Learning from both in-plant and industry experience can help enhance safety and reduce the cost of plant operations. Utility engineers currently assess events that occur in nuclear plants throughout the world for in-plant applicability. Established computer information networks, documents, bulletins, and other information sources provide a large number of event descriptions to help individual plants benefit from this industry experience. The activities for coordinating reviews of event descriptions from other plants for in-plant applications require substantial engineering time to collect, organize, evaluate, and apply. Data-base tools can help engineers efficiently handle and sort the data so that they can concentrate on understanding the importance of the event, developing cost-effective interventions, and communicating implementation plans for plant improvement. An Electric Power Research Institute human reliability project has developed a classification system with modern data-base software to help engineers efficiently process, assess, and apply information contained in the events to enhance plant operation. Plant-specific classification of industry experience provides a practical method for efficiently taking into account industry when planning maintenance activities and reviewing plant safety

Price-transparency and cost accounting: challenges for health care organizations in the consumer-driven era.

Science.gov (United States)

Hilsenrath, Peter; Eakin, Cynthia; Fischer, Katrina

2015-01-01

Health care reform is directed toward improving access and quality while containing costs. An essential part of this is improvement of pricing models to more accurately reflect the costs of providing care. Transparent prices that reflect costs are necessary to signal information to consumers and producers. This information is central in a consumer-driven marketplace. The rapid increase in high deductible insurance and other forms of cost sharing incentivizes the search for price information. The organizational ability to measure costs across a cycle of care is an integral component of creating value, and will play a greater role as reimbursements transition to episode-based care, value-based purchasing, and accountable care organization models. This article discusses use of activity-based costing (ABC) to better measure the cost of health care. It describes examples of ABC in health care organizations and discusses impediments to adoption in the United States including cultural and institutional barriers. © The Author(s) 2015.

Improved, low cost inorganic-organic separators for rechargeable silver-zinc batteries

Science.gov (United States)

Sheibley, D. W.

1979-01-01

Several flexible, low-cost inorganic-organic separators with performance characteristics and cycle life equal to, or better than, the Lewis Research Center Astropower separator were developed. These new separators can be made on continuous-production equipment at about one-fourth the cost of the Astropower separator produced the same way. In test cells, these new separators demonstrate cycle life improvement, acceptable operating characteristics, and uniform current density. The various separator formulas, test cell construction, and data analysis are described.

Design reliability engineering

International Nuclear Information System (INIS)

Buden, D.; Hunt, R.N.M.

1989-01-01

Improved design techniques are needed to achieve high reliability at minimum cost. This is especially true of space systems where lifetimes of many years without maintenance are needed and severe mass limitations exist. Reliability must be designed into these systems from the start. Techniques are now being explored to structure a formal design process that will be more complete and less expensive. The intent is to integrate the best features of design, reliability analysis, and expert systems to design highly reliable systems to meet stressing needs. Taken into account are the large uncertainties that exist in materials, design models, and fabrication techniques. Expert systems are a convenient method to integrate into the design process a complete definition of all elements that should be considered and an opportunity to integrate the design process with reliability, safety, test engineering, maintenance and operator training. 1 fig

2015 NREL Photovoltaic Module Reliability Workshops

Energy Technology Data Exchange (ETDEWEB)

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

2017-09-14

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) 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.

2016 NREL Photovoltaic Module Reliability Workshop

Energy Technology Data Exchange (ETDEWEB)

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

2017-09-07

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) 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.

Residential outage cost estimation: Hong Kong

International Nuclear Information System (INIS)

Woo, C.K.; Ho, T.; Shiu, A.; Cheng, Y.S.; Horowitz, I.; Wang, J.

2014-01-01

Hong Kong has almost perfect electricity reliability, the result of substantial investments ultimately financed by electricity consumers who may be willing to accept lower reliability in exchange for lower bills. But consumers with high outage costs are likely to reject the reliability reduction. Our ordered-logit regression analysis of the responses by 1876 households to a telephone survey conducted in June 2013 indicates that Hong Kong residents exhibit a statistically-significant preference for their existing service reliability and rate. Moreover, the average residential cost estimate for a 1-h outage is US$45 (HK$350), topping the estimates reported in 10 of the 11 studies published in the last 10 years. The policy implication is that absent additional compelling evidence, Hong Kong should not reduce its service reliability. - Highlights: • Use a contingent valuation survey to obtain residential preferences for reliability. • Use an ordered logit analysis to estimate Hong Kong's residential outage costs. • Find high outage cost estimates that imply high reliability requirements. • Conclude that sans new evidence, Hong Kong should not reduce its reliability

Nutrient and Organic Carbon Losses, Enrichment Rate, and Cost of Water Erosion

Directory of Open Access Journals (Sweden)

Ildegardis Bertol

Full Text Available ABSTRACT Soil erosion from water causes loss of nutrients and organic carbon, enriches the environment outside the erosion site, and results in costs. The no-tillage system generates increased nutrient and C content in the topsoil and, although it controls erosion, it can produce a more enriched runoff than in the conventional tillage system. This study was conducted in a Humic Cambisol in natural rainfall from 1997 to 2012 to quantify the contents and total losses of nutrients and organic C in soil runoff, and to calculate the enrichment rates and the cost of these losses. The treatments evaluated were: a soil with a crop, consisting of conventional tillage with one plowing + two harrowings (CT, minimum tillage with one chisel plowing + one harrowing (MT, and no tillage (NT; and b bare soil: one plowing + two harrowings (BS. In CT, MT, and NT, black oat, soybean, vetch, corn, turnip, and black beans were cultivated. Over the 15 years, 15.5 Mg ha-1 of limestone, 525 kg ha-1 of N (urea, 1,302 kg ha-1 of P2O5 (triple superphosphate, and 1,075 kg ha-1 of K2O (potassium chloride were used in the soil. The P, K, Ca, Mg, and organic C contents in the soil were determined and also the P, K, Ca, and Mg sediments in the runoff water. From these contents, the total losses, the enrichment rates (ER, and financial losses were calculated. The NT increased the P, K, and organic C contents in the topsoil. The nutrients and organic C content in the runoff from NT was greater than from CT, showing that NT was not a fully conservationist practice for soil. The linear model y = a + bx fit the data within the level of significance (p≤0.01 when the values of P, K, and organic C in the sediments from erosion were related to those values in the soil surface layer. The nutrient and organic C contents were higher in the sediments from erosion than in the soil where the erosion originated, generating values of ER>1 for P, K, and organic C. The value of the total losses

Design for low-power and reliable flexible electronics

Science.gov (United States)

Huang, Tsung-Ching (Jim)

Flexible electronics are emerging as an alternative to conventional Si electronics for large-area low-cost applications such as e-paper, smart sensors, and disposable RFID tags. By utilizing inexpensive manufacturing methods such as ink-jet printing and roll-to-roll imprinting, flexible electronics can be made on low-cost plastics just like printing a newspaper. However, the key elements of exible electronics, thin-film transistors (TFTs), have slower operating speeds and less reliability than their Si electronics counterparts. Furthermore, depending on the material property, TFTs are usually mono-type -- either p- or n-type -- devices. Making air-stable complementary TFT circuits is very challenging and not applicable to most TFT technologies. Existing design methodologies for Si electronics, therefore, cannot be directly applied to exible electronics. Other inhibiting factors such as high supply voltage, large process variation, and lack of trustworthy device modeling also make designing larger-scale and robust TFT circuits a significant challenge. The major goal of this dissertation is to provide a viable solution for robust circuit design in exible electronics. I will first introduce a reliability simulation framework that can predict the degraded TFT circuits' performance under bias-stress. This framework has been validated using the amorphous-silicon (a-Si) TFT scan driver for TFT-LCD displays. To reuse the existing CMOS design ow for exible electronics, I propose a Pseudo-CMOS cell library that can make TFT circuits operable under low supply voltage and which has post-fabrication tunability for reliability and performance enhancement. This cell library has been validated using 2V self-assembly-monolayer (SAM) organic TFTs with a low-cost shadow-mask deposition process. I will also demonstrate a 3-bit 1.25KS/s Flash ADC in a-Si TFTs, which is based on the proposed Pseudo-CMOS cell library, and explore more possibilities in display, energy, and sensing

Reliability data banks

International Nuclear Information System (INIS)

Cannon, A.G.; Bendell, A.

1991-01-01

Following an introductory chapter on Reliability, what is it, why it is needed, how it is achieved and measured, the principles of reliability data bases and analysis methodologies are the subject of the next two chapters. Achievements due to the development of data banks are mentioned for different industries in the next chapter, FACTS, a comprehensive information system for industrial safety and reliability data collection in process plants are covered next. CREDO, the Central Reliability Data Organization is described in the next chapter and is indexed separately, as is the chapter on DANTE, the fabrication reliability Data analysis system. Reliability data banks at Electricite de France and IAEA's experience in compiling a generic component reliability data base are also separately indexed. The European reliability data system, ERDS, and the development of a large data bank come next. The last three chapters look at 'Reliability data banks, - friend foe or a waste of time'? and future developments. (UK)

Reliability engineering for nuclear and other high technology systems

International Nuclear Information System (INIS)

Lakner, A.A.; Anderson, R.T.

1985-01-01

This book is written for the reliability instructor, program manager, system engineer, design engineer, reliability engineer, nuclear regulator, probability risk assessment (PRA) analyst, general manager and others who are involved in system hardware acquisition, design and operation and are concerned with plant safety and operational cost-effectiveness. It provides criteria, guidelines and comprehensive engineering data affecting reliability; it covers the key aspects of system reliability as it relates to conceptual planning, cost tradeoff decisions, specification, contractor selection, design, test and plant acceptance and operation. It treats reliability as an integrated methodology, explicitly describing life cycle management techniques as well as the basic elements of a total hardware development program, including: reliability parameters and design improvement attributes, reliability testing, reliability engineering and control. It describes how these elements can be defined during procurement, and implemented during design and development to yield reliable equipment. (author)

Reliability Worth Analysis of Distribution Systems Using Cascade Correlation Neural Networks

DEFF Research Database (Denmark)

Heidari, Alireza; Agelidis, Vassilios; Pou, Josep

2018-01-01

Reliability worth analysis is of great importance in the area of distribution network planning and operation. The reliability worth's precision can be affected greatly by the customer interruption cost model used. The choice of the cost models can change system and load point reliability indices....... In this study, a cascade correlation neural network is adopted to further develop two cost models comprising a probabilistic distribution model and an average or aggregate model. A contingency-based analytical technique is adopted to conduct the reliability worth analysis. Furthermore, the possible effects...

Quality assurance and reliability in the Japanese electronics industry

Science.gov (United States)

Pecht, Michael; Boulton, William R.

1995-02-01

Quality and reliability are two attributes required for all Japanese products, although the JTEC panel found these attributes to be secondary to customer cost requirements. While our Japanese hosts gave presentations on the challenges of technology, cost, and miniaturization, quality and reliability were infrequently the focus of our discussions. Quality and reliability were assumed to be sufficient to meet customer needs. Fujitsu's slogan, 'quality built-in, with cost and performance as prime consideration,' illustrates this point. Sony's definition of a next-generation product is 'one that is going to be half the size and half the price at the same performance of the existing one'. Quality and reliability are so integral to Japan's electronics industry that they need no new emphasis.

On the Path to SunShot - The Role of Advancements in Solar Photovoltaic Efficiency, Reliability, and Costs

Energy Technology Data Exchange (ETDEWEB)

Woodhouse, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jones-Albertus, Rebecca [Dept. of Energy (DOE), Washington DC (United States); Feldman, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Fu, Ran [National Renewable Energy Lab. (NREL), Golden, CO (United States); Horowitz, Kelsey [National Renewable Energy Lab. (NREL), Golden, CO (United States); Chung, Donald [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jordan, Dirk [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kurtz, Sarah [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-05-01

Although tremendous progress has been made in reducing the cost of PV systems, additional LCOE reductions of 40%–50% between 2015 and 2020 will be required to reach the SunShot Initiative’s targets (see Woodhouse et al. 2016). Understanding the tradeoffs between installed prices and other PV system characteristics—such as module efficiency, module degradation rate, and system lifetime—are vital. For example, with 29%-efficient modules and high reliability (a 50-year lifetime and a 0.2%/year module degradation rate), a residential PV system could achieve the SunShot LCOE goal with modules priced at almost $1.20/W. But change the lifetime to 10 years and the degradation rate to 2%/year, and the system would need those very high-efficiency modules at zero cost to achieve the same LCOE. Although these examples are extreme, they serve to illustrate the wide range of technological combinations that could help drive PV toward the LCOE goals. SunShot’s PV roadmaps illustrate specific potential pathways to the target cost reductions.

Leadership in organizations with high security and reliability requirements; Liderazgo en organizaciones con altos requisitos de seguridad y fiabilidad

Energy Technology Data Exchange (ETDEWEB)

Gonzalez, F.

2013-07-01

Developing leadership skills in organizations is the key to ensure the sustain ability of excellent results in industries with high requirements safety and reliability. In order to have a model of leadership development specific to this type of organizations, Tecnatom in 2011, we initiated a project internal, to find and adapt a competency model to these requirements.

Design for Reliability in Renewable Energy Systems

DEFF Research Database (Denmark)

Blaabjerg, Frede; Zhou, Dao; Sangwongwanich, Ariya

2017-01-01

Power electronics are widely used in renewable energy systems to achieve lower cost of energy, higher efficiency and high power density. At the same time, the high reliability of the power electronics products is demanded, in order to reduce the failure rates and ensure cost-effective operation...... of the renewable energy systems. This paper thus describes the basic concepts used in reliability engineering, and presents the status and future trends of Design for Reliability (DfR) in power electronics, which is currently undergoing a paradigm shift to a physics-of-failure approach. Two case studies of a 2 MW...

Factors Influencing Organization Adoption Decision On Cloud Computing

OpenAIRE

Ailar Rahimli

2013-01-01

Cloud computing is a developing field, using by organization that require to computing resource to provide the organizational computing needs. The goal of this research is evaluate the factors that influence on organization decision to adopt the cloud computing in Malaysia. Factors that relate to cloud computing adoption that include : need for cloud computing, cost effectiveness, security effectiveness of cloud computing and reliability. This paper evaluated the factors that influence on ado...

Development and application of a cost-benefit framework for energy reliability. Using probabilistic methods in network planning and regulation to enhance social welfare. The N-1 rule

International Nuclear Information System (INIS)

Nooij, Michiel de; Baarsma, Barbara; Bloemhof, Gabriel; Dijk, Harold; Slootweg, Han

2010-01-01

Although electricity is crucial to many activities in developed societies, guaranteeing a maximum reliability of supply to end-users is extremely costly. This situation gives rise to a trade-off between the costs and benefits of reliability. The Dutch government has responded to this trade-off by changing the rule stipulating that electricity networks must be able to maintain supply even if one component fails (known as the N-1 rule), even in maintenance situations. This rule was changed by adding the phrase 'unless the costs exceed the benefits.' We have developed a cost-benefit framework for the implementation and application of this new rule. The framework requires input on failure probability, the cost of supply interruptions to end-users and the cost of investments. A case study of the Dutch grid shows that the method is indeed practicable and that it is highly unlikely that N-1 during maintenance will enhance welfare in the Netherlands. Therefore, including the limitation 'unless the costs exceed the benefits' in the rule has been a sensible policy for the Netherlands, and would also be a sensible policy for other countries. (author)

Acquisition of reliable vacuum hardware for large accelerator systems

International Nuclear Information System (INIS)

Welch, K.M.

1995-01-01

Credible and effective communications prove to be the major challenge in the acquisition of reliable vacuum hardware. Technical competence is necessary but not sufficient. The authors must effectively communicate with management, sponsoring agencies, project organizations, service groups, staff and with vendors. Most of Deming's 14 quality assurance tenants relate to creating an enlightened environment of good communications. All projects progress along six distinct, closely coupled, dynamic phases. All six phases are in a state of perpetual change. These phases and their elements are discussed, with emphasis given to the acquisition phase and its related vocabulary. Large projects require great clarity and rigor as poor communications can be costly. For rigor to be cost effective, it can't be pedantic. Clarity thrives best in a low-risk, team environment

Reliability-based performance simulation for optimized pavement maintenance

International Nuclear Information System (INIS)

Chou, Jui-Sheng; Le, Thanh-Son

2011-01-01

Roadway pavement maintenance is essential for driver safety and highway infrastructure efficiency. However, regular preventive maintenance and rehabilitation (M and R) activities are extremely costly. Unfortunately, the funds available for the M and R of highway pavement are often given lower priority compared to other national development policies, therefore, available funds must be allocated wisely. Maintenance strategies are typically implemented by optimizing only the cost whilst the reliability of facility performance is neglected. This study proposes a novel algorithm using multi-objective particle swarm optimization (MOPSO) technique to evaluate the cost-reliability tradeoff in a flexible maintenance strategy based on non-dominant solutions. Moreover, a probabilistic model for regression parameters is employed to assess reliability-based performance. A numerical example of a highway pavement project is illustrated to demonstrate the efficacy of the proposed MOPSO algorithms. The analytical results show that the proposed approach can help decision makers to optimize roadway maintenance plans. - Highlights: →A novel algorithm using multi-objective particle swarm optimization technique. → Evaluation of the cost-reliability tradeoff in a flexible maintenance strategy. → A probabilistic model for regression parameters is employed to assess reliability-based performance. → The proposed approach can help decision makers to optimize roadway maintenance plans.

Reliability-based performance simulation for optimized pavement maintenance

Energy Technology Data Exchange (ETDEWEB)

Chou, Jui-Sheng, E-mail: jschou@mail.ntust.edu.tw [Department of Construction Engineering, National Taiwan University of Science and Technology (Taiwan Tech), 43 Sec. 4, Keelung Rd., Taipei 106, Taiwan (China); Le, Thanh-Son [Department of Construction Engineering, National Taiwan University of Science and Technology (Taiwan Tech), 43 Sec. 4, Keelung Rd., Taipei 106, Taiwan (China)

2011-10-15

Roadway pavement maintenance is essential for driver safety and highway infrastructure efficiency. However, regular preventive maintenance and rehabilitation (M and R) activities are extremely costly. Unfortunately, the funds available for the M and R of highway pavement are often given lower priority compared to other national development policies, therefore, available funds must be allocated wisely. Maintenance strategies are typically implemented by optimizing only the cost whilst the reliability of facility performance is neglected. This study proposes a novel algorithm using multi-objective particle swarm optimization (MOPSO) technique to evaluate the cost-reliability tradeoff in a flexible maintenance strategy based on non-dominant solutions. Moreover, a probabilistic model for regression parameters is employed to assess reliability-based performance. A numerical example of a highway pavement project is illustrated to demonstrate the efficacy of the proposed MOPSO algorithms. The analytical results show that the proposed approach can help decision makers to optimize roadway maintenance plans. - Highlights: > A novel algorithm using multi-objective particle swarm optimization technique. > Evaluation of the cost-reliability tradeoff in a flexible maintenance strategy. > A probabilistic model for regression parameters is employed to assess reliability-based performance. > The proposed approach can help decision makers to optimize roadway maintenance plans.

Offshore wind turbines reliability, availability and maintenance

CERN Document Server

Tavner, Peter

2012-01-01

The first book to specifically focus on offshore wind turbine technology and which addresses practically wind turbine reliability and availability. The book draws on the author's experience of power generation reliability and availability and the condition monitoring of that plant to describe the problems facing the developers of offshore wind farms and the solutions available to them to raise availability, reduce cost of energy and improve through life cost.

48 CFR 225.7303-2 - Cost of doing business with a foreign government or an international organization.

Science.gov (United States)

2010-10-01

... reasonable and allocable costs of doing business with a foreign government or international organization... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Cost of doing business with a foreign government or an international organization. 225.7303-2 Section 225.7303-2 Federal...

Product reliability and thin-film photovoltaics

Science.gov (United States)

Gaston, Ryan; Feist, Rebekah; Yeung, Simon; Hus, Mike; Bernius, Mark; Langlois, Marc; Bury, Scott; Granata, Jennifer; Quintana, Michael; Carlson, Carl; Sarakakis, Georgios; Ogden, Douglas; Mettas, Adamantios

2009-08-01

Despite significant growth in photovoltaics (PV) over the last few years, only approximately 1.07 billion kWhr of electricity is estimated to have been generated from PV in the US during 2008, or 0.27% of total electrical generation. PV market penetration is set for a paradigm shift, as fluctuating hydrocarbon prices and an acknowledgement of the environmental impacts associated with their use, combined with breakthrough new PV technologies, such as thin-film and BIPV, are driving the cost of energy generated with PV to parity or cost advantage versus more traditional forms of energy generation. In addition to reaching cost parity with grid supplied power, a key to the long-term success of PV as a viable energy alternative is the reliability of systems in the field. New technologies may or may not have the same failure modes as previous technologies. Reliability testing and product lifetime issues continue to be one of the key bottlenecks in the rapid commercialization of PV technologies today. In this paper, we highlight the critical need for moving away from relying on traditional qualification and safety tests as a measure of reliability and focus instead on designing for reliability and its integration into the product development process. A drive towards quantitative predictive accelerated testing is emphasized and an industrial collaboration model addressing reliability challenges is proposed.

First evidence on the validity and reliability of the Safety Organizing Scale-Nursing Home version (SOS-NH).

Science.gov (United States)

Ausserhofer, Dietmar; Anderson, Ruth A; Colón-Emeric, Cathleen; Schwendimann, René

2013-08-01

The Safety Organizing Scale is a valid and reliable measure on safety behaviors and practices in hospitals. This study aimed to explore the psychometric properties of the Safety Organizing Scale-Nursing Home version (SOS-NH). In a cross-sectional analysis of staff survey data, we examined validity and reliability of the 9-item Safety SOS-NH using American Educational Research Association guidelines. This substudy of a larger trial used baseline survey data collected from staff members (n = 627) in a variety of work roles in 13 nursing homes (NHs) in North Carolina and Virginia. Psychometric evaluation of the SOS-NH revealed good response patterns with low average of missing values across all items (3.05%). Analyses of the SOS-NH's internal structure (eg, comparative fit indices = 0.929, standardized root mean square error of approximation = 0.045) and consistency (composite reliability = 0.94) suggested its 1-dimensionality. Significant between-facility variability, intraclass correlations, within-group agreement, and design effect confirmed appropriateness of the SOS-NH for measurement at the NH level, justifying data aggregation. The SOS-NH showed discriminate validity from one related concept: communication openness. Initial evidence regarding validity and reliability of the SOS-NH supports its utility in measuring safety behaviors and practices among a wide range of NH staff members, including those with low literacy. Further psychometric evaluation should focus on testing concurrent and criterion validity, using resident outcome measures (eg, patient fall rates). Copyright © 2013 American Medical Directors Association, Inc. All rights reserved.

Time-Varying, Multi-Scale Adaptive System Reliability Analysis of Lifeline Infrastructure Networks

Energy Technology Data Exchange (ETDEWEB)

Gearhart, Jared Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kurtz, Nolan Scot [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2014-09-01

The majority of current societal and economic needs world-wide are met by the existing networked, civil infrastructure. Because the cost of managing such infrastructure is high and increases with time, risk-informed decision making is essential for those with management responsibilities for these systems. To address such concerns, a methodology that accounts for new information, deterioration, component models, component importance, group importance, network reliability, hierarchical structure organization, and efficiency concerns has been developed. This methodology analyzes the use of new information through the lens of adaptive Importance Sampling for structural reliability problems. Deterioration, multi-scale bridge models, and time-variant component importance are investigated for a specific network. Furthermore, both bridge and pipeline networks are studied for group and component importance, as well as for hierarchical structures in the context of specific networks. Efficiency is the primary driver throughout this study. With this risk-informed approach, those responsible for management can address deteriorating infrastructure networks in an organized manner.

Final radioactive waste disposal: A European comparison of organization and costs

International Nuclear Information System (INIS)

Drasdo, P.

2000-01-01

The investigation is aimed to the comparison of organization structures of operators (plants) and governmental institutions concerned with the final disposal of radioactive waste. The study is covering Germany, France, United Kingdom and Sweden. The capital amount of total final disposal costs are the highest in Germany, the lowest in Sweden. This is also true for the final disposal costs that have to be financed by electricity production from nuclear power plants. The reasons for the differences with respect to economic efficiencies, political decisions and technical concepts are discussed

On the reliability of spacecraft swarms

NARCIS (Netherlands)

Engelen, S.; Gill, E.K.A.; Verhoeven, C.J.M.

2012-01-01

Satellite swarms, consisting of a large number of identical, miniaturized and simple satellites, are claimed to provide an implementation for specific space missions which require high reliability. However, a consistent model of how reliability and availability on mission level is linked to cost-

Cost analysis of the Hemodialysis Reliable Outflow (HeRO) Graft compared to the tunneled dialysis catheter.

Science.gov (United States)

Al Shakarchi, Julien; Inston, Nicholas; Jones, Robert G; Maclaine, Grant; Hollinworth, David

2016-04-01

In end-stage renal disease patients with central venous obstruction, who have limited vascular access options, the Hemodialysis Reliable Outflow (HeRO) Graft is a new alternative with a lower incidence of complications and longer effective device life compared to tunneled dialysis catheters (TDCs). We undertook an economic analysis of introducing the HeRO Graft in the UK. A 1-year cost-consequence decision analytic model was developed comparing management with the HeRO Graft to TDCs from the perspective of the National Health Service in England. The model comprises four 3-month cycles during which the vascular access option either remains functional for hemodialysis or fails, patients can experience access-related infection and device thrombosis, and they can also accrue associated costs. Clinical input data were sourced from published studies and unit cost data from National Health Service 2014-15 Reference Costs. In the base case, a 100-patient cohort managed with the HeRO Graft experienced 6 fewer failed devices, 53 fewer access-related infections, and 67 fewer device thromboses compared to patients managed with TDCs. Although the initial device and placement costs for the HeRO Graft are greater than those for TDCs, savings from the lower incidence of device complications and longer effective device patency reduces these costs. Overall net annual costs are £2600 for each HeRO Graft-managed patient compared to TDC-managed patients. If the National Health Service were to reimburse hemodialysis at a uniform rate regardless of the type of vascular access, net 1-year savings of £1200 per patient are estimated for individuals managed with the HeRO Graft. The base case results showed a marginal net positive cost associated with vascular access with the HeRO Graft compared with TDCs for the incremental clinical benefit of reductions in patency failures, device-related thrombosis, and access-related infection events in a patient population with limited options for

Staff downsizing on the decline for organizations trying to cut overall health care costs.

Science.gov (United States)

1998-04-01

Data Benchmarks: Don't look to downsizing as a major cost-cutting strategy this year. This industry study identifies staffing strategies at hospitals nationwide, plus other important human resource issues for 1998. Not surprisingly, controlling organization-wide costs is a top priority. Here are the details.

A parametric cost model for estimating operating and support costs of US Navy (non-nuclear) surface ships

OpenAIRE

Brandt, James M.

1999-01-01

Approved for public release; distribution is unlimited With few effective decision-making tools to assess the affordability of major weapon systems, management of total ownership costs is continually misunderstood. Cost analysis provides a quick and reliable assessment of affordability. Because there is no standardized method for calculating reliable estimates of operating and support (O&S) costs (the principal component of total ownership cost), this thesis formulates a parametric cost mo...

A Review of Recent RTO Benefit-Cost Studies: Toward MoreComprehensive Assessments of FERC Electricity RestructuringPolicies

Energy Technology Data Exchange (ETDEWEB)

Eto, Joseph H.; Lesieutre, Bernard C.

2005-12-01

During the past three years, government and private organizations have issued more than a dozen studies of the benefits and costs of Regional Transmission Organizations (RTOs). Most of these studies have focused on benefits that can be readily estimated using traditional production-cost simulation techniques, which compare the cost of centralized dispatch under an RTO to dispatch in the absence of an RTO, and on costs associated with RTO start-up and operation. Taken as a whole, it is difficult to draw definitive conclusions from these studies because they have not examined potentially much larger benefits (and costs) resulting from the impacts of RTOs on reliability management, generation and transmission investment and operation, and wholesale electricity market operation. This report: (1) Describes the history of benefit-cost analysis of FERC electricity restructuring policies; (2)Reviews current practice by analyzing 11 RTO benefit-cost studies that were published between 2002 and 2004 and makes recommendations to improve the documentation of data and methods and the presentation of findings in future studies that focus primarily on estimating short-run economic impacts; and (3) Reviews important impacts of FERC policies that have been overlooked or incompletely treated by recent RTO benefit-cost studies and the challenges to crafting more comprehensive assessments of these impacts based on actual performance, including impacts on reliability management, generation and transmission investment and operation, and wholesale electricity market operation.

ESCAF - Failure simulation and reliability calculation device

International Nuclear Information System (INIS)

Laviron, A.; Berard, C.; Quenee, R.

1979-01-01

Reliability studies of nuclear power plant safety functions have, up to now, required the use of large computers. As they are of universal use, these big machines are not very well adapted to deal with reliability problems at low cost. ESCAF has been developed to be substituted for large computers in order to save time and money. ESCAF is a small electronic device which can be used in connection with a minicomputer. It allows to perform complex system reliability analysis (qualitative and quantitative) and to study critical element influences such as common cause failures. In this paper, the device is described and its features and abilities are outlined: easy to implement, swift running, low working cost. Its application range concerns all cases when a good reliability is needed

The value of service reliability

OpenAIRE

Benezech , Vincent; Coulombel , Nicolas

2013-01-01

International audience; This paper studies the impact of service frequency and reliability on the choice of departure time and the travel cost of transit users. When the user has (α, β, γ) scheduling preferences, we show that the optimal head start decreases with service reliability, as expected. It does not necessarily decrease with service frequency, however. We derive the value of service headway (VoSH) and the value of service reliability (VoSR), which measure the marginal effect on the e...

Reliability and Maintenance for Offshore Wind Turbines and Wave Energy Devices

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2015-01-01

Wind turbines are in some countries contributing significantly the production of electricity and wave energy devices have the potential to be developed in a similarway. For both offshore wind turbines and wave energy devices reliability is a key issue since costs to operation and maintenance may...... be significant contributors to the Levelized Cost Of Energy and OM costs are highly dependent on the reliability of the components implying that it is important to focus on increasing the reliability as much as is economically reasonable. This paper describes basic aspects for reliability analysis of wind...... turbines and wave energy devices with special focus on structural components. The reliability assessment needs include the effects of the control system and possible faults due to failure of electrical/mechanical components and e.g. loss of grid connection. The target reliability level for wind turbine...

AECL's reliability and maintainability program

International Nuclear Information System (INIS)

Wolfe, W.A.; Nieuwhof, G.W.E.

1976-05-01

AECL's reliability and maintainability program for nuclear generating stations is described. How the various resources of the company are organized to design and construct stations that operate reliably and safely is shown. Reliability and maintainability includes not only special mathematically oriented techniques, but also the technical skills and organizational abilities of the company. (author)

Highly Reliable Organizations in the Onshore Natural Gas Sector: An Assessment of Current Practices, Regulatory Frameworks, and Select Case Studies

Energy Technology Data Exchange (ETDEWEB)

Logan, Jeffrey S. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Paranhos, Elizabeth [Energy Innovation Partners, Seattle, WA (United States); Kozak, Tracy G. [Energy Innovation Partners, Seattle, WA (United States); Boyd, William [Univ. of Colorado, Boulder, CO (United States)

2017-07-31

This study focuses on onshore natural gas operations and examines the extent to which oil and gas firms have embraced certain organizational characteristics that lead to 'high reliability' - understood here as strong safety and reliability records over extended periods of operation. The key questions that motivated this study include whether onshore oil and gas firms engaged in exploration and production (E&P) and midstream (i.e., natural gas transmission and storage) are implementing practices characteristic of high reliability organizations (HROs) and the extent to which any such practices are being driven by industry innovations and standards and/or regulatory requirements.

Organic Versus Contractor Logistics Support For Depot-Level Repair: Factors That Drive Sub-Optimal Decisions

Science.gov (United States)

2016-02-16

incentive.26 CLS benefits the government because contractors control sustainment costs to maximize their profit . For the government, profit is not part...system, less maintenance, and thereby obtain better aircraft reliability, thereby maximizing profits by lowering maintenance costs.27 Government fiscal...sustainment plan. 6 Profit Incentive as Part of CLS Costs Organic support on average should be cheaper than CLS because there is no profit

Reliability and Characterization of High Voltage Power Capacitors

Science.gov (United States)

2014-03-01

in a Faraday cage to minimize external noise. In addition, electron microscopy could also be performed to identify the change in trap concentration...military bases in the United States. Energy product reliability affects the sustainability and cost- effectiveness of these systems, which must be tested...Energy product reliability affects the sustainability and cost- effectiveness of these systems, which must be tested by outside entities to ensure

Organization and costs of repurchasing, transportation, warehousing and storage of raspberry fruit

Directory of Open Access Journals (Sweden)

Kalanović-Bulatović Branka

2015-01-01

Full Text Available Due to its characteristic, apart from nutritive and medical significance, raspberry is particularly important for our country in social and economic terms, since its export attracts foreign currency inflow. Since the quality of raspberry decreases rapidly after picking, it is utterly important that the whole process, from picking to cold storage of fruit, should be rationally organized, thus finally reducing the costs and increasing the production value. For these reasons precisely the research deals with organization of the entire process, from repurchase to cold storage of raspberry fruits, as well as the analysis of pertaining costs. Necessary information for the preparation of the paper has been obtained from cold storage plants engaged in raspberry storage and preservation. Necessary information has been gathered using several methods, viz: observation, interview and content analysis methods. Furthermore, analysis, comparison and calculation methods have also been used in the preparation of the paper. The raspberry fruit repurchase, transport and storage costs range from 1,6 to 1,8 EUR per kg, exclusive of storage (store-housing. To this one should add store-housing costs ranging from 0,009 to 0,013 EUR per kg on a monthly basis. Modern organization of production and communication between producers, repurchasers, processors and exporters is essential in order to decrease fluctuations in repurchase and sales price of fresh raspberry and its products and the improvement of overall financial effect of all links within the chain of this economy activity. Cold storage plants, even if of minor capacities, are beneficial not only for the immediate participants in the producer-buyer chain, but it also makes an important stimulating factor for rural development and economy of the country.

48 CFR 731.770 - OMB Circular A-122, cost principles for nonprofit organizations; USAID implementation.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false OMB Circular A-122, cost principles for nonprofit organizations; USAID implementation. 731.770 Section 731.770 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT GENERAL CONTRACTING REQUIREMENTS CONTRACT COST...

Benchmarking DFT and semi-empirical methods for a reliable and cost-efficient computational screening of benzofulvene derivatives as donor materials for small-molecule organic solar cells.

Science.gov (United States)

Tortorella, Sara; Talamo, Maurizio Mastropasqua; Cardone, Antonio; Pastore, Mariachiara; De Angelis, Filippo

2016-02-24

A systematic computational investigation on the optical properties of a group of novel benzofulvene derivatives (Martinelli 2014 Org. Lett. 16 3424-7), proposed as possible donor materials in small molecule organic photovoltaic (smOPV) devices, is presented. A benchmark evaluation against experimental results on the accuracy of different exchange and correlation functionals and semi-empirical methods in predicting both reliable ground state equilibrium geometries and electronic absorption spectra is carried out. The benchmark of the geometry optimization level indicated that the best agreement with x-ray data is achieved by using the B3LYP functional. Concerning the optical gap prediction, we found that, among the employed functionals, MPW1K provides the most accurate excitation energies over the entire set of benzofulvenes. Similarly reliable results were also obtained for range-separated hybrid functionals (CAM-B3LYP and wB97XD) and for global hybrid methods incorporating a large amount of non-local exchange (M06-2X and M06-HF). Density functional theory (DFT) hybrids with a moderate (about 20-30%) extent of Hartree-Fock exchange (HFexc) (PBE0, B3LYP and M06) were also found to deliver HOMO-LUMO energy gaps which compare well with the experimental absorption maxima, thus representing a valuable alternative for a prompt and predictive estimation of the optical gap. The possibility of using completely semi-empirical approaches (AM1/ZINDO) is also discussed.

Benchmarking DFT and semi-empirical methods for a reliable and cost-efficient computational screening of benzofulvene derivatives as donor materials for small-molecule organic solar cells

International Nuclear Information System (INIS)

Tortorella, Sara; Talamo, Maurizio Mastropasqua; Cardone, Antonio; Pastore, Mariachiara; De Angelis, Filippo

2016-01-01

A systematic computational investigation on the optical properties of a group of novel benzofulvene derivatives (Martinelli 2014 Org. Lett. 16 3424–7), proposed as possible donor materials in small molecule organic photovoltaic (smOPV) devices, is presented. A benchmark evaluation against experimental results on the accuracy of different exchange and correlation functionals and semi-empirical methods in predicting both reliable ground state equilibrium geometries and electronic absorption spectra is carried out. The benchmark of the geometry optimization level indicated that the best agreement with x-ray data is achieved by using the B3LYP functional. Concerning the optical gap prediction, we found that, among the employed functionals, MPW1K provides the most accurate excitation energies over the entire set of benzofulvenes. Similarly reliable results were also obtained for range-separated hybrid functionals (CAM-B3LYP and wB97XD) and for global hybrid methods incorporating a large amount of non-local exchange (M06-2X and M06-HF). Density functional theory (DFT) hybrids with a moderate (about 20–30%) extent of Hartree–Fock exchange (HFexc) (PBE0, B3LYP and M06) were also found to deliver HOMO–LUMO energy gaps which compare well with the experimental absorption maxima, thus representing a valuable alternative for a prompt and predictive estimation of the optical gap. The possibility of using completely semi-empirical approaches (AM1/ZINDO) is also discussed. (paper)

Application of low cost technology for the management of irrgation in organic orchads

Science.gov (United States)

Horcajo, Daniel; Patrícia Prazeres Marques, Karina; Rodríguez Sinobas, Leonor

2014-05-01

Throughout history, humans have cyclically return to their old traditions such as the organic orchards. Nowadays, these have been integrated into the modern cities and could supply fresh vegetables to the daily food improving human health. Organic orchards grow crops without pesticides and artificial fertilizers thus, they are respectful with the environment and guarantee the food's safety . In modern society, the application of new technology is a must, in this case to obtain an efficient irrigation. In order to monitor a proper irrigation and save water and energy, soil water content probes are used to measure soil water content. Among them, capacitive probes ,monitored with a specific data logger, are typically used. Most of them, specially the data loggers, are expensive and in many cases are not used. In this work, we have applied the open hardware Arduino to build and program a low cost datalogger for the programming of irrigation in an experimental organic orchard. Results showed that the application of such as low cost technology, which is easily available in the market and easy to understand, everyone can built and program its own device helping in managing water resources in organic orchards .

ITO-free flexible organic solar cells with printed current collecting grids

NARCIS (Netherlands)

Galagan, Y.O.; Rubingh, J.E.J.M.; Andriessen, H.A.J.M.; Fan, C.C.; Blom, P.W.M.; Veenstra, S.C.; Kroon, J.M.

2011-01-01

The presence of a transparent conductive electrode such as indium tin oxide (ITO) limits the reliability and cost price of organic photovoltaic devices as it is brittle and expensive. Moreover, the relative high sheet resistance of an ITO electrode on flexible substrates limits the maximum width of

Application of reliability methods in Ontario Hydro

International Nuclear Information System (INIS)

Jeppesen, R.; Ravishankar, T.J.

1985-01-01

Ontario Hydro have established a reliability program in support of its substantial nuclear program. Application of the reliability program to achieve both production and safety goals is described. The value of such a reliability program is evident in the record of Ontario Hydro's operating nuclear stations. The factors which have contributed to the success of the reliability program are identified as line management's commitment to reliability; selective and judicious application of reliability methods; establishing performance goals and monitoring the in-service performance; and collection, distribution, review and utilization of performance information to facilitate cost-effective achievement of goals and improvements. (orig.)

Can non-destructive inspection be reliable

International Nuclear Information System (INIS)

Silk, M.G.; Stoneham, A.M.; Temple, J.A.G.

1988-01-01

The paper on inspection is based on the book ''The reliability of non-destructive inspection: assessing the assessment of structures under stress'' by the present authors (published by Adam Hilger 1987). Emphasis is placed on the reliability of inspection and whether cracks in welds or flaws in components can be detected. The need for non-destructive testing and the historical attitudes to non-destructive testing are outlined, along with the case of failure. Factors influencing reliable inspection are discussed, and defect detection trials involving round robin tests are described. The development of reliable inspection techniques and the costs of reliability and unreliability are also examined. (U.K.)

Low-cost solution to the grid reliability problem with 100% penetration of intermittent wind, water, and solar for all purposes.

Science.gov (United States)

Jacobson, Mark Z; Delucchi, Mark A; Cameron, Mary A; Frew, Bethany A

2015-12-08

This study addresses the greatest concern facing the large-scale integration of wind, water, and solar (WWS) into a power grid: the high cost of avoiding load loss caused by WWS variability and uncertainty. It uses a new grid integration model and finds low-cost, no-load-loss, nonunique solutions to this problem on electrification of all US energy sectors (electricity, transportation, heating/cooling, and industry) while accounting for wind and solar time series data from a 3D global weather model that simulates extreme events and competition among wind turbines for available kinetic energy. Solutions are obtained by prioritizing storage for heat (in soil and water); cold (in ice and water); and electricity (in phase-change materials, pumped hydro, hydropower, and hydrogen), and using demand response. No natural gas, biofuels, nuclear power, or stationary batteries are needed. The resulting 2050-2055 US electricity social cost for a full system is much less than for fossil fuels. These results hold for many conditions, suggesting that low-cost, reliable 100% WWS systems should work many places worldwide.

Multiobjective Reliable Cloud Storage with Its Particle Swarm Optimization Algorithm

Directory of Open Access Journals (Sweden)

Xiyang Liu

2016-01-01

Full Text Available Information abounds in all fields of the real life, which is often recorded as digital data in computer systems and treated as a kind of increasingly important resource. Its increasing volume growth causes great difficulties in both storage and analysis. The massive data storage in cloud environments has significant impacts on the quality of service (QoS of the systems, which is becoming an increasingly challenging problem. In this paper, we propose a multiobjective optimization model for the reliable data storage in clouds through considering both cost and reliability of the storage service simultaneously. In the proposed model, the total cost is analyzed to be composed of storage space occupation cost, data migration cost, and communication cost. According to the analysis of the storage process, the transmission reliability, equipment stability, and software reliability are taken into account in the storage reliability evaluation. To solve the proposed multiobjective model, a Constrained Multiobjective Particle Swarm Optimization (CMPSO algorithm is designed. At last, experiments are designed to validate the proposed model and its solution PSO algorithm. In the experiments, the proposed model is tested in cooperation with 3 storage strategies. Experimental results show that the proposed model is positive and effective. The experimental results also demonstrate that the proposed model can perform much better in alliance with proper file splitting methods.

High-Reliability Health Care: Getting There from Here

Science.gov (United States)

Chassin, Mark R; Loeb, Jerod M

2013-01-01

Context Despite serious and widespread efforts to improve the quality of health care, many patients still suffer preventable harm every day. Hospitals find improvement difficult to sustain, and they suffer “project fatigue” because so many problems need attention. No hospitals or health systems have achieved consistent excellence throughout their institutions. High-reliability science is the study of organizations in industries like commercial aviation and nuclear power that operate under hazardous conditions while maintaining safety levels that are far better than those of health care. Adapting and applying the lessons of this science to health care offer the promise of enabling hospitals to reach levels of quality and safety that are comparable to those of the best high-reliability organizations. Methods We combined the Joint Commission's knowledge of health care organizations with knowledge from the published literature and from experts in high-reliability industries and leading safety scholars outside health care. We developed a conceptual and practical framework for assessing hospitals’ readiness for and progress toward high reliability. By iterative testing with hospital leaders, we refined the framework and, for each of its fourteen components, defined stages of maturity through which we believe hospitals must pass to reach high reliability. Findings We discovered that the ways that high-reliability organizations generate and maintain high levels of safety cannot be directly applied to today's hospitals. We defined a series of incremental changes that hospitals should undertake to progress toward high reliability. These changes involve the leadership's commitment to achieving zero patient harm, a fully functional culture of safety throughout the organization, and the widespread deployment of highly effective process improvement tools. Conclusions Hospitals can make substantial progress toward high reliability by undertaking several specific

Design of preventive maintenance system using the reliability engineering and maintenance value stream mapping methods in PT. XYZ

Science.gov (United States)

Sembiring, N.; Panjaitan, N.; Angelita, S.

2018-02-01

PT. XYZ is a company owned by non-governmental organizations engaged in the field of production of rubber processing becoming crumb rubber. Part of the production is supported by some of machines and interacting equipment to achieve optimal productivity. Types of the machine that are used in the production process are Conveyor Breaker, Breaker, Rolling Pin, Hammer Mill, Mill Roll, Conveyor, Shredder Crumb, and Dryer. Maintenance system in PT. XYZ is corrective maintenance i.e. repairing or replacing the engine components after the crash on the machine. Replacement of engine components on corrective maintenance causes the machine to stop operating during the production process is in progress. The result is in the loss of production time due to the operator must replace the damaged engine components. The loss of production time can impact on the production targets which were not reached and lead to high loss costs. The cost for all components is Rp. 4.088.514.505. This cost is really high just for maintaining a Mill Roll Machine. Therefore PT. XYZ is needed to do preventive maintenance i.e. scheduling engine components and improving maintenance efficiency. The used methods are Reliability Engineering and Maintenance Value Stream Mapping (MVSM). The needed data in this research are the interval of time damage to engine components, opportunity cost, labor cost, component cost, corrective repair time, preventive repair time, Mean Time To Opportunity (MTTO), Mean Time To Repair (MTTR), and Mean Time To Yield (MTTY). In this research, the critical components of Mill Roll machine are Spier, Bushing, Bearing, Coupling and Roll. Determination of damage distribution, reliability, MTTF, cost of failure, cost of preventive, current state map, and future state map are done so that the replacement time for each critical component with the lowest maintenance cost and preparation of Standard Operation Procedure (SOP) are developed. For the critical component that has been

Reliability of large superconducting magnets through design

International Nuclear Information System (INIS)

Henning, C.D.

1980-01-01

As superconducting magnet systems grow larger and become the central component of major systems involving fusion, magnetohydrodynamics, and high-energy physics, their reliability must be commensurate with the enormous capital investment in the projects. Although the magnet may represent only 15% of the cost of a large system such as the Mirror Fusion Test Facility, its failure would be catastrophic to the entire investment. Effective quality control during construction is one method of ensuring success. However, if the design is unforgiving, even an inordinate amount of effort expended on quality control may be inadequate. Creative design is the most effective way of ensuring magnet reliability and providing a reasonable limit on the amount of quality control needed. For example, by subjecting the last drawing operation is superconductor manufacture to a stress larger than the magnet design stress, a 100% proof test is achieved; cabled conductors offer mechanical redundancy, as do some methods of conductor joining; ground-plane insulation should be multilayered to prevent arcs, and interturn and interlayer insulation spaced to be compatible with the self-extinguishing of arcs during quench voltages; electrical leads should be thermally protected; and guard vacuum spaces can be incorporated to control helium leaks. Many reliable design options are known to magnet designers. These options need to be documented and organized to produce a design guide. Eventually, standard procedures, safety factors, and design codes can lead to reliability in magnets comparable to that obtained in pressure vessels and other structures. Wihout such reliability, large-scale applications in major systems employing magnetic fusion energy, magnetohydrodynamics, or high-energy physics would present unacceptable economic risks

Transaction Costs, the Phenomenon of the Trading House and Economic Organization

Directory of Open Access Journals (Sweden)

Kiryanov Igor, V.

2015-12-01

Full Text Available The present paper contains a study of the phenomenon of company’s specific internal divisions called “trading house”. The analysis of different approaches (based on results obtained by R. Coase and O. Williamson towards the problem of impact of transaction cost on company size leads to the following conclusion: the company size mostly depends on its institutional architecture which includes specific divisions that ensure outsourcing of intergroup transaction cost. I propose to call these divisions centers of transaction cost. I suppose that the wide popularity of trading houses among companies belonging to different branches can be explained by the fact that a trading house is mostly used not as selling and purchasing division, but as a center of transaction cost that concentrates the biggest transaction cost (by its share within company’s general expenses. This reasoning leads to possibility of existence of a set of methodological principles that allow to build up an a priori model of expanding company. The process of expansion represents a series of inclusion of centers of transactions cost by the company after institutional advantages of an earlier institutional architecture disappear. This methodology allows to set up a classification between a classical company as a structure with low level of integration and frozen institutional architecture and an economic organization that represents an explicitly constructed composition including centers of transaction cost that help to extend the transformational space of an expanding company.

18 CFR 39.11 - Reliability reports.

Science.gov (United States)

2010-04-01

... Electric Reliability Organization shall conduct assessments of the adequacy of the Bulk-Power System in... assessments as determined by the Commission of the reliability of the Bulk-Power System in North America and... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Reliability reports. 39...

Power Industry Reliability Coordination in Asia in a Market Environment

OpenAIRE

Hammons, Thomas J.; Voropai, Nikolai I.

2010-01-01

This paper addresses the problems of power supply reliability in a market environment. The specific features of economic interrelations between the power supply organization and consumers in terms of reliability assurance are examined and the principles of providing power supply reliability are formulated. The economic mechanisms of coordinating the interests of power supply organization and consumers to provide power supply reliability are discussed. Reliability of restructuring China's powe...

Photovoltaic performance and reliability workshop

Energy Technology Data Exchange (ETDEWEB)

Mrig, L. [ed.

1993-12-01

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.

Optimal design of water supply networks for enhancing seismic reliability

International Nuclear Information System (INIS)

Yoo, Do Guen; Kang, Doosun; Kim, Joong Hoon

2016-01-01

The goal of the present study is to construct a reliability evaluation model of a water supply system taking seismic hazards and present techniques to enhance hydraulic reliability of the design into consideration. To maximize seismic reliability with limited budgets, an optimal design model is developed using an optimization technique called harmony search (HS). The model is applied to actual water supply systems to determine pipe diameters that can maximize seismic reliability. The reliabilities between the optimal design and existing designs were compared and analyzed. The optimal design would both enhance reliability by approximately 8.9% and have a construction cost of approximately 1.3% less than current pipe construction cost. In addition, the reinforcement of the durability of individual pipes without considering the system produced ineffective results in terms of both cost and reliability. Therefore, to increase the supply ability of the entire system, optimized pipe diameter combinations should be derived. Systems in which normal status hydraulic stability and abnormal status available demand could be maximally secured if configured through the optimal design. - Highlights: • We construct a seismic reliability evaluation model of water supply system. • We present technique to enhance hydraulic reliability in the aspect of design. • Harmony search algorithm is applied in optimal designs process. • The effects of the proposed optimal design are improved reliability about by 9%. • Optimized pipe diameter combinations should be derived indispensably.

Cost-effectiveness analysis of computerized ECG interpretation system in an ambulatory health care organization.

Science.gov (United States)

Carel, R S

1982-04-01

The cost-effectiveness of a computerized ECG interpretation system in an ambulatory health care organization has been evaluated in comparison with a conventional (manual) system. The automated system was shown to be more cost-effective at a minimum load of 2,500 patients/month. At larger monthly loads an even greater cost-effectiveness was found, the average cost/ECG being about $2. In the manual system the cost/unit is practically independent of patient load. This is primarily due to the fact that 87% of the cost/ECG is attributable to wages and fees of highly trained personnel. In the automated system, on the other hand, the cost/ECG is heavily dependent on examinee load. This is due to the relatively large impact of equipment depreciation on fixed (and total) cost. Utilization of a computer-assisted system leads to marked reduction in cardiologists' interpretation time, substantially shorter turnaround time (of unconfirmed reports), and potential provision of simultaneous service at several remotely located "heart stations."

Field reliability of electronic systems

International Nuclear Information System (INIS)

Elm, T.

1984-02-01

This report investigates, through several examples from the field, the reliability of electronic units in a broader sense. That is, it treats not just random parts failure, but also inadequate reliability design and (externally and internally) induced failures. The report is not meant to be merely an indication of the state of the art for the reliability prediction methods we know, but also as a contribution to the investigation of man-machine interplay in the operation and repair of electronic equipment. The report firmly links electronics reliability to safety and risk analyses approaches with a broader, system oriented view of reliability prediction and with postfailure stress analysis. It is intended to reveal, in a qualitative manner, the existence of symptom and cause patterns. It provides a background for further investigations to identify the detailed mechanisms of the faults and the remedical actions and precautions for achieving cost effective reliability. (author)

Safety and reliability in Europe

International Nuclear Information System (INIS)

Colombo, A.G.

1985-01-01

This volume contains the papers presented at the ESRA Pre-Launching Meeting. The meeting was attended by about eighty European reliability and safety experts from industry, research organizations and universities. This meeting was dealing with the following subjects: the historical perspective of safety and reliability in Europe and to the aims of ESRA. Status and Trends in Research and Development; Codes, Standards and Regulations; Academic and Technical Training. National and international Organizations. Twenty six papers have been analyzed and abstracted for inclusion in the data base

Reliability Oriented Circuit Design For Power Electronics Applications

DEFF Research Database (Denmark)

Sintamarean, Nicolae Cristian

is presented. Chapter 3 presents the electro-thermal model validation and the reliability studies performed by the proposed tool. The chapter ends with a detailed lifetime analysis, which emphasizes the mission-profile variation and gate-driver parameters variation impact on the PV-inverter devices lifetime......Highly reliable components are required in order to minimize the downtime during the lifetime of the converter and implicitly the maintenance costs. Therefore, the design of high reliable converters under constrained reliability and cost is a great challenge to be overcome in the future....... Moreover, the impact of the mission-profile sampling time on the lifetime estimation accuracy is also determined. The second part of the thesis introduced in Chapter 4, presents a novel gate-driver concept which reduces the dependency of the device power losses variations on the device loading variations...

Reliability-oriented energy storage sizing in wind power systems

DEFF Research Database (Denmark)

Qin, Zian; Liserre, Marco; Blaabjerg, Frede

2014-01-01

Energy storage can be used to suppress the power fluctuations in wind power systems, and thereby reduce the thermal excursion and improve the reliability. Since the cost of the energy storage in large power application is high, it is crucial to have a better understanding of the relationship...... between the size of the energy storage and the reliability benefit it can generate. Therefore, a reliability-oriented energy storage sizing approach is proposed for the wind power systems, where the power, energy, cost and the control strategy of the energy storage are all taken into account....... With the proposed approach, the computational effort is reduced and the impact of the energy storage system on the reliability of the wind power converter can be quantified....

Reliability Based Optimization of Structural Systems

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

1987-01-01

The optimization problem to design structural systems such that the reliability is satisfactory during the whole lifetime of the structure is considered in this paper. Some of the quantities modelling the loads and the strength of the structure are modelled as random variables. The reliability...... is estimated using first. order reliability methods ( FORM ). The design problem is formulated as the optimization problem to minimize a given cost function such that the reliability of the single elements satisfies given requirements or such that the systems reliability satisfies a given requirement....... For these optimization problems it is described how a sensitivity analysis can be performed. Next, new optimization procedures to solve the optimization problems are presented. Two of these procedures solve the system reliability based optimization problem sequentially using quasi-analytical derivatives. Finally...

Power transformer reliability modelling

NARCIS (Netherlands)

Schijndel, van A.

2010-01-01

Problem description Electrical power grids serve to transport and distribute electrical power with high reliability and availability at acceptable costs and risks. These grids play a crucial though preferably invisible role in supplying sufficient power in a convenient form. Today’s society has

Thermal Management and Reliability of Automotive Power Electronics and Electric Machines

Energy Technology Data Exchange (ETDEWEB)

Narumanchi, Sreekant V [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Bennion, Kevin S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Cousineau, Justine E [National Renewable Energy Laboratory (NREL), Golden, CO (United States); DeVoto, Douglas J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Feng, Xuhui [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kekelia, Bidzina [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kozak, Joseph P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Major, Joshua [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Moreno, Gilberto [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Paret, Paul P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tomerlin, Jeff J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-02-09

Low-cost, high-performance thermal management technologies are helping meet aggressive power density, specific power, cost, and reliability targets for power electronics and electric machines. The National Renewable Energy Laboratory is working closely with numerous industry and research partners to help influence development of components that meet aggressive performance and cost targets through development and characterization of cooling technologies, and thermal characterization and improvements of passive stack materials and interfaces. Thermomechanical reliability and lifetime estimation models are important enablers for industry in cost-and time-effective design.

Contribution to high voltage matrix switches reliability

International Nuclear Information System (INIS)

Lausenaz, Yvan

2000-01-01

Nowadays, power electronic equipment requirements are important, concerning performances, quality and reliability. On the other hand, costs have to be reduced in order to satisfy the market rules. To provide cheap, reliability and performances, many standard components with mass production are developed. But the construction of specific products must be considered following these two different points: in one band you can produce specific components, with delay, over-cost problems and eventuality quality and reliability problems, in the other and you can use standard components in a adapted topologies. The CEA of Pierrelatte has adopted this last technique of power electronic conception for the development of these high voltage pulsed power converters. The technique consists in using standard components and to associate them in series and in parallel. The matrix constitutes high voltage macro-switch where electrical parameters are distributed between the synchronized components. This study deals with the reliability of these structures. It brings up the high reliability aspect of MOSFETs matrix associations. Thanks to several homemade test facilities, we obtained lots of data concerning the components we use. The understanding of defects propagation mechanisms in matrix structures has allowed us to put forwards the necessity of robust drive system, adapted clamping voltage protection, and careful geometrical construction. All these reliability considerations in matrix associations have notably allowed the construction of a new matrix structure regrouping all solutions insuring reliability. Reliable and robust, this product has already reaches the industrial stage. (author) [fr

Preventive maintenance and reliability-centered maintenance

International Nuclear Information System (INIS)

Anderson, J.G.

1989-01-01

In the recent past, the primary function of the preventive maintenance program at a nuclear power plant was to maintain the operability and reliability of the plant. Reducing overall maintenance costs by performing effective preventive maintenance, instead of more costly and disruptive corrective maintenance, instead of more costly and disruptive corrective maintenance, was a secondary consideration. In today's operating environment, the preventive maintenance program must meet the test of cost-effectiveness as well as many new standards for performance that are being required by rate regulators. The preventive maintenance program must be able to withstand the challenge of independent audit to a new standard of technical adequacy and compliance with recommendations from component vendors. In this new environment, the standard that is being applied at the San Onofre nuclear generating station (SONGS) is that the preventive maintenance program must meet the test of cost-effectiveness, improve equipment performance, support increased plant availability, and (a) literally implement the recommendations of the vendor, (b) provide other compensation for the vendor recommendation, or (c) provide technical justification for the deviation. The subject of this paper is the way that reliability-centered maintenance (RCM) is helping SONGS meet these challenges

MEMS reliability: coming of age

Science.gov (United States)

Douglass, Michael R.

2008-02-01

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.

Reliability: How much is it worth? Beyond its estimation or prediction, the (net) present value of reliability

International Nuclear Information System (INIS)

Saleh, J.H.; Marais, K.

2006-01-01

In this article, we link an engineering concept, reliability, to a financial and managerial concept, net present value, by exploring the impact of a system's reliability on its revenue generation capability. The framework here developed for non-repairable systems quantitatively captures the value of reliability from a financial standpoint. We show that traditional present value calculations of engineering systems do not account for system reliability, thus over-estimate a system's worth and can therefore lead to flawed investment decisions. It is therefore important to involve reliability engineers upfront before investment decisions are made in technical systems. In addition, the analyses here developed help designers identify the optimal level of reliability that maximizes a system's net present value-the financial value reliability provides to the system minus the cost to achieve this level of reliability. Although we recognize that there are numerous considerations driving the specification of an engineering system's reliability, we contend that the financial analysis of reliability here developed should be made available to decision-makers to support in part, or at least be factored into, the system reliability specification

Review of Reliability Assessment of Westinghouse SSPS Using SPC by WEC

International Nuclear Information System (INIS)

Kang, H. T.; Chung, H. Y.

2007-01-01

Westinghouse Electric Company (WEC) has accomplished the reliability assessment of Westinghouse Solid State Protection System (SSPS) in KORI no. 2, 3, 4, and YGN no. 1, 2. In their studies, it is reported that creating a cost-effective plan for improving the reliability of the SSPS and at KORI no. 2, 3 and 4, and YGN no. 1, 2 should be needed while reducing their maintenance cost. In this paper, we reviewed the reliability assessment of Westinghouse SSPS analyzed in two performance standards, availability, and the maintenance expense using Statistic Process Control (SPC). As a result, it is concluded all plants have several failures reported but no effect on the system's availability, and the maintenance expense analysis did not reduce the current maintenance expense by 30%. Therefore, overall review for the reliability assessment is that a new strategy for cost-effective plan and/or upgrade approach for improving the reliability of the aging Westinghouse SSPS should be needed

Photovoltaic energy cost limit

International Nuclear Information System (INIS)

Coiante, D.

1992-01-01

Referring to a photovoltaic system for grid connected applications, a parametric expression of kWh cost is derived. The limit of kWh cost is carried out extrapolating the values of cost components to their lowest figure. The reliability of the forecast is checked by disaggregating kWh cost in direct and indirect costs and by discussing the possible cost reduction of each component

Reliability of two social cognition tests: The combined stories test and the social knowledge test.

Science.gov (United States)

Thibaudeau, Élisabeth; Cellard, Caroline; Legendre, Maxime; Villeneuve, Karèle; Achim, Amélie M

2018-04-01

Deficits in social cognition are common in psychiatric disorders. Validated social cognition measures with good psychometric properties are necessary to assess and target social cognitive deficits. Two recent social cognition tests, the Combined Stories Test (COST) and the Social Knowledge Test (SKT), respectively assess theory of mind and social knowledge. Previous studies have shown good psychometric properties for these tests, but the test-retest reliability has never been documented. The aim of this study was to evaluate the test-retest reliability and the inter-rater reliability of the COST and the SKT. The COST and the SKT were administered twice to a group of forty-two healthy adults, with a delay of approximately four weeks between the assessments. Excellent test-retest reliability was observed for the COST, and a good test-retest reliability was observed for the SKT. There was no evidence of practice effect. Furthermore, an excellent inter-rater reliability was observed for both tests. This study shows a good reliability of the COST and the SKT that adds to the good validity previously reported for these two tests. These good psychometrics properties thus support that the COST and the SKT are adequate measures for the assessment of social cognition. Copyright © 2018. Published by Elsevier B.V.

Safety and reliability of automatization software

Energy Technology Data Exchange (ETDEWEB)

Kapp, K; Daum, R [Karlsruhe Univ. (TH) (Germany, F.R.). Lehrstuhl fuer Angewandte Informatik, Transport- und Verkehrssysteme

1979-02-01

Automated technical systems have to meet very high requirements concerning safety, security and reliability. Today, modern computers, especially microcomputers, are used as integral parts of those systems. In consequence computer programs must work in a safe and reliable mannter. Methods are discussed which allow to construct safe and reliable software for automatic systems such as reactor protection systems and to prove that the safety requirements are met. As a result it is shown that only the method of total software diversification can satisfy all safety requirements at tolerable cost. In order to achieve a high degree of reliability, structured and modular programming in context with high level programming languages are recommended.

High-reliability health care: getting there from here.

Science.gov (United States)

Chassin, Mark R; Loeb, Jerod M

2013-09-01

Despite serious and widespread efforts to improve the quality of health care, many patients still suffer preventable harm every day. Hospitals find improvement difficult to sustain, and they suffer "project fatigue" because so many problems need attention. No hospitals or health systems have achieved consistent excellence throughout their institutions. High-reliability science is the study of organizations in industries like commercial aviation and nuclear power that operate under hazardous conditions while maintaining safety levels that are far better than those of health care. Adapting and applying the lessons of this science to health care offer the promise of enabling hospitals to reach levels of quality and safety that are comparable to those of the best high-reliability organizations. We combined the Joint Commission's knowledge of health care organizations with knowledge from the published literature and from experts in high-reliability industries and leading safety scholars outside health care. We developed a conceptual and practical framework for assessing hospitals' readiness for and progress toward high reliability. By iterative testing with hospital leaders, we refined the framework and, for each of its fourteen components, defined stages of maturity through which we believe hospitals must pass to reach high reliability. We discovered that the ways that high-reliability organizations generate and maintain high levels of safety cannot be directly applied to today's hospitals. We defined a series of incremental changes that hospitals should undertake to progress toward high reliability. These changes involve the leadership's commitment to achieving zero patient harm, a fully functional culture of safety throughout the organization, and the widespread deployment of highly effective process improvement tools. Hospitals can make substantial progress toward high reliability by undertaking several specific organizational change initiatives. Further research

Reliability and cost/worth evaluation of generating systems utilizing wind and solar energy

Science.gov (United States)

Bagen

The utilization of renewable energy resources such as wind and solar energy for electric power supply has received considerable attention in recent years due to adverse environmental impacts and fuel cost escalation associated with conventional generation. At the present time, wind and/or solar energy sources are utilized to generate electric power in many applications. Wind and solar energy will become important sources for power generation in the future because of their environmental, social and economic benefits, together with public support and government incentives. The wind and sunlight are, however, unstable and variable energy sources, and behave far differently than conventional sources. Energy storage systems are, therefore, often required to smooth the fluctuating nature of the energy conversion system especially in small isolated applications. The research work presented in this thesis is focused on the development and application of reliability and economic benefits assessment associated with incorporating wind energy, solar energy and energy storage in power generating systems. A probabilistic approach using sequential Monte Carlo simulation was employed in this research and a number of analyses were conducted with regards to the adequacy and economic assessment of generation systems containing wind energy, solar energy and energy storage. The evaluation models and techniques incorporate risk index distributions and different operating strategies associated with diesel generation in small isolated systems. Deterministic and probabilistic techniques are combined in this thesis using a system well-being approach to provide useful adequacy indices for small isolated systems that include renewable energy and energy storage. The concepts presented and examples illustrated in this thesis will help power system planners and utility managers to assess the reliability and economic benefits of utilizing wind energy conversion systems, solar energy conversion

The cost management organization: the next step for materiel management.

Science.gov (United States)

Schuweiler, R C

1997-06-01

, it should be easy to rest on these laurels and simply operate. However, we believe that this is just a beginning. A new generation of highly educated leaders are emerging and taking advantage of the contributions of pioneers who laid the ground work. These new leaders will have advanced management, statistics, and behavioral sciences skills. They will be analysts and organizational motivators. Their goal will be to improve financial and clinical performance measured by real time process and performance data. The new leaders will have information at their fingertips thanks to significant leaps forward in data collection, automated continuous replenishment processes, and software designed for better management of clinical and cost outcomes. This article documents significant Materiel management accomplishments and conceptualizes cost management processes. The cost management organization is the logical evolution in our efforts for better outcomes in healthcare Materiel management.

Safeprops: A Software for Fast and Reliable Estimation of Safety and Environmental Properties for Organic Compounds

DEFF Research Database (Denmark)

Jones, Mark Nicholas; Frutiger, Jerome; Abildskov, Jens

We present a new software tool called SAFEPROPS which is able to estimate major safety-related and environmental properties for organic compounds. SAFEPROPS provides accurate, reliable and fast predictions using the Marrero-Gani group contribution (MG-GC) method. It is implemented using Python...... as the main programming language, while the necessary parameters together with their correlation matrix are obtained from a SQLite database which has been populated using off-line parameter and error estimation routines (Eq. 3-8)....

Evaluation of Stock Management Strategies Reliability at Dependent Demand

Directory of Open Access Journals (Sweden)

Lukinskiy Valery

2017-03-01

Full Text Available For efficiently increasing the logistic systems, the core specialists’ attention has to be directed to reducing costs and increasing supply chains reliability. A decent attention to costs reduction has already been paid, so it can be stated that in this way there is a significant progress. But the problem of reliability evaluation is still insufficiently explored, particularly, in such an important sphere as inventory management at the dependent demand.

Space solar array reliability: A study and recommendations

Science.gov (United States)

Brandhorst, Henry W., Jr.; Rodiek, Julie A.

2008-12-01

Providing reliable power over the anticipated mission life is critical to all satellites; therefore solar arrays are one of the most vital links to satellite mission success. Furthermore, solar arrays are exposed to the harshest environment of virtually any satellite component. In the past 10 years 117 satellite solar array anomalies have been recorded with 12 resulting in total satellite failure. Through an in-depth analysis of satellite anomalies listed in the Airclaim's Ascend SpaceTrak database, it is clear that solar array reliability is a serious, industry-wide issue. Solar array reliability directly affects the cost of future satellites through increased insurance premiums and a lack of confidence by investors. Recommendations for improving reliability through careful ground testing, standardization of testing procedures such as the emerging AIAA standards, and data sharing across the industry will be discussed. The benefits of creating a certified module and array testing facility that would certify in-space reliability will also be briefly examined. Solar array reliability is an issue that must be addressed to both reduce costs and ensure continued viability of the commercial and government assets on orbit.

Photovoltaic Module Reliability Workshop 2010: February 18-19, 2010

Energy Technology Data Exchange (ETDEWEB)

Kurtz, J.

2013-11-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) 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.

Photovoltaic Module Reliability Workshop 2011: February 16-17, 2011

Energy Technology Data Exchange (ETDEWEB)

Kurtz, S.

2013-11-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) 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.

Photovoltaic Module Reliability Workshop 2013: February 26-27, 2013

Energy Technology Data Exchange (ETDEWEB)

Kurtz, S.

2013-10-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) 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.

Photovoltaic Module Reliability Workshop 2014: February 25-26, 2014

Energy Technology Data Exchange (ETDEWEB)

Kurtz, S.

2014-02-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) 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.

Integrated Reliability-Based Optimal Design of Structures

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Thoft-Christensen, Palle

1987-01-01

In conventional optimal design of structural systems the weight or the initial cost of the structure is usually used as objective function. Further, the constraints require that the stresses and/or strains at some critical points have to be less than some given values. Finally, all variables......-based optimal design is discussed. Next, an optimal inspection and repair strategy for existing structural systems is presented. An optimization problem is formulated , where the objective is to minimize the expected total future cost of inspection and repair subject to the constraint that the reliability...... value. The reliability can be measured from an element and/or a systems point of view. A number of methods to solve reliability-based optimization problems has been suggested, see e.g. Frangopol [I]. Murotsu et al. (2], Thoft-Christensen & Sørensen (3] and Sørensen (4). For structures where...

Approach for an integral power transformer reliability model

NARCIS (Netherlands)

Schijndel, van A.; Wouters, P.A.A.F.; Steennis, E.F.; Wetzer, J.M.

2012-01-01

In electrical power transmission and distribution networks power transformers represent a crucial group of assets both in terms of reliability and investments. In order to safeguard the required quality at acceptable costs, decisions must be based on a reliable forecast of future behaviour. The aim

Reliability issues : a Canadian perspective

International Nuclear Information System (INIS)

Konow, H.

2004-01-01

A Canadian perspective of power reliability issues was presented. Reliability depends on adequacy of supply and a framework for standards. The challenges facing the electric power industry include new demand, plant replacement and exports. It is expected that demand will by 670 TWh by 2020, with 205 TWh coming from new plants. Canada will require an investment of $150 billion to meet this demand and the need is comparable in the United States. As trade grows, the challenge becomes a continental issue and investment in the bi-national transmission grid will be essential. The 5 point plan of the Canadian Electricity Association is to: (1) establish an investment climate to ensure future electricity supply, (2) move government and industry towards smart and effective regulation, (3) work to ensure a sustainable future for the next generation, (4) foster innovation and accelerate skills development, and (5) build on the strengths of an integrated North American system to maximize opportunity for Canadians. The CEA's 7 measures that enhance North American reliability were listed with emphasis on its support for a self-governing international organization for developing and enforcing mandatory reliability standards. CEA also supports the creation of a binational Electric Reliability Organization (ERO) to identify and solve reliability issues in the context of a bi-national grid. tabs., figs

The Use of Questionnaires in Safety Culture Studies in High Reliability Organizations. Literature Review and an Application in the Spanish Nuclear Sector

International Nuclear Information System (INIS)

German, S.; Navajas, J.; Silla, I.

2014-01-01

This report examines two aspects related to the use of questionnaires in safety culture research conducted in high reliability organizations. First, a literature review of recent studies that address safety culture through questionnaires is presented. Literature review showed that most studies used only questionnaires as a research technique, were cross-sectional, applied paper-based questionnaires, and were conducted in one type of high reliability organization. Second, a research project on safety culture that used electronic surveys in a sample of experts on safety culture is discussed. This project, developed by CISOT-CIEMAT research institute, was carry out in the Spanish nuclear sector and illustrates relevant aspects of the methodological design and administration processes that must be considered to encourage participation in the study.. (Author)

Transportation reliability and trip satisfaction.

Science.gov (United States)

2012-10-01

Travel delays and associated costs have become a major problem in Michigan over the : past several decades as congestion has continued to increase, creating significant negative : impacts on travel reliability on many roadways throughout the State. T...

Scoping study on trends in the economic value of electricity reliability to the U.S. economy

Energy Technology Data Exchange (ETDEWEB)

Eto, Joseph; Koomey, Jonathan; Lehman, Bryan; Martin, Nathan; Mills, Evan; Webber, Carrie; Worrell, Ernst

2001-06-01

During the past three years, working with more than 150 organizations representing public and private stakeholders, EPRI has developed the Electricity Technology Roadmap. The Roadmap identifies several major strategic challenges that must be successfully addressed to ensure a sustainable future in which electricity continues to play an important role in economic growth. Articulation of these anticipated trends and challenges requires a detailed understanding of the role and importance of reliable electricity in different sectors of the economy. This report is intended to contribute to that understanding by analyzing key aspects of trends in the economic value of electricity reliability in the U.S. economy. We first present a review of recent literature on electricity reliability costs. Next, we describe three distinct end-use approaches for tracking trends in reliability needs: (1) an analysis of the electricity-use requirements of office equipment in different commercial sectors; (2) an examination of the use of aggregate statistical indicators of industrial electricity use and economic activity to identify high reliability-requirement customer market segments; and (3) a case study of cleanrooms, which is a cross-cutting market segment known to have high reliability requirements. Finally, we present insurance industry perspectives on electricity reliability as an example of a financial tool for addressing customers' reliability needs.

An Investment Level Decision Method to Secure Long-term Reliability

Science.gov (United States)

Bamba, Satoshi; Yabe, Kuniaki; Seki, Tomomichi; Shibaya, Tetsuji

The slowdown in power demand increase and facility replacement causes the aging and lower reliability in power facility. And the aging is followed by the rapid increase of repair and replacement when many facilities reach their lifetime in future. This paper describes a method to estimate the repair and replacement costs in future by applying the life-cycle cost model and renewal theory to the historical data. This paper also describes a method to decide the optimum investment plan, which replaces facilities in the order of cost-effectiveness by setting replacement priority formula, and the minimum investment level to keep the reliability. Estimation examples applied to substation facilities show that the reasonable and leveled future cash-out can keep the reliability by lowering the percentage of replacements caused by fatal failures.

Are We Hoping For A Bounce A Study On Resilience And Human Relations In A High Reliability Organization

Science.gov (United States)

2016-03-01

negatively impact the organization’s resilience when faced with workplace stressors (Gittell, 2008, p. 26). Consequently, this reduces an organization’s...2014). Organizational resilience and the challenge for human resource management: Conceptualizations and frameworks for theory and practice. Paper...A BOUNCE? A STUDY ON RESILIENCE AND HUMAN RELATIONS IN A HIGH RELIABILITY ORGANIZATION by Robert D. Johns March 2016 Thesis Advisor

Health care utilization and cost among children with asthma who were enrolled in a health maintenance organization.

Science.gov (United States)

Lozano, P; Fishman, P; VonKorff, M; Hecht, J

1997-06-01

To measure the impact of asthma on the use and cost of health care by children in a managed care organization. Population-based historical cohort study. A medium-sized staff model health maintenance organization in western Washington state. All 71 818 children, between age 1 to 17 years, who were enrolled and used services during 1992. Children were identified with one or more asthma diagnoses during 1992 using automated encounter data. Nonurgent outpatient visits, pharmacy fills, urgent care visits, and hospital days, as well as associated costs were measured. All services were categorized as asthma care or nonasthma care. Multivariate regression analysis was used to compute marginal cost for asthma (difference in total cost between children with asthma and other children using services, adjusted for covariates). Treated prevalence of asthma was 4.9%. Children with asthma incurred 88% more costs ($1060.32 vs $563. 81/yr), filled 2.77 times as many prescriptions (11.59 vs 4.19/yr), made 65% more nonurgent outpatient visits (5.75 vs 3.48/yr), and had twice as many inpatient days (.23 vs .11/yr) compared with the general population of children using services. Asthma care represented 37% of all health care received by children with asthma, while the remaining 63% were for nonasthma services. Almost two-thirds of asthma-related costs were attributable to nonurgent outpatient care and prescriptions; only one third was attributable to urgent care and hospitalizations. Controlling for age, sex, and comorbidities, the marginal cost of asthma was $615.17/yr (95% confidence interval $502.73, $727.61), which includes asthma as well as nonasthma services. This marginal cost represents 58% of all health care costs for children with asthma. Children with asthma use significantly more health services (and incur significantly more costs) than other children using services, attributable largely to asthma care. The majority of all health care costs for children with asthma were for

The reliability of financial information of charitable organizations: an exploratory study based on the Benford’s Law

Directory of Open Access Journals (Sweden)

Marco Antonio Figueiredo Milani Filho

2013-08-01

Full Text Available Benford's Law (BL is a logarithmic distribution which is useful to detect abnormal patterns of digits in number sets. It is often used as a primary data auditing method for detecting traces of errors, illegal practices or undesired occurrences, such as fraud and earning management. In this descriptive study, I analyzed the financial information (revenue and expenditure of the registered charitable hospitals located in Ontario and Quebec, which have the majority (71.4% of these organizations within Canada. The aim of this study was to verify the reliability of the financial data of the respective hospitals, using the probability distribution predicted by Benford’s Law as a proxy of reliability. The sample was composed by 1,334 observations related to 339 entities operating in the tax year 2009 and 328 entities in 2010, gathered from the Canada Revenue Agency’s database. To analyze the discrepancies between the actual and expected frequencies of the significant-digit, two statistics were calculated: Z-test and Pearson’s chi-square test. The results show that, with a confidence level of 95%, the data set of the organizations located in Ontario and Quebec have similar distribution to the BL, suggesting that, in a preliminary analysis, their financial data are free from bias.

Reliability and Availability of Cloud Computing

CERN Document Server

Bauer, Eric

2012-01-01

A holistic approach to service reliability and availability of cloud computing Reliability and Availability of Cloud Computing provides IS/IT system and solution architects, developers, and engineers with the knowledge needed to assess the impact of virtualization and cloud computing on service reliability and availability. It reveals how to select the most appropriate design for reliability diligence to assure that user expectations are met. Organized in three parts (basics, risk analysis, and recommendations), this resource is accessible to readers of diverse backgrounds and experience le

Reliability of power system with open access

International Nuclear Information System (INIS)

Ehsani, A.; Ranjbar, A. M.; Fotuhi Firuzabad, M.; Ehsani, M.

2003-01-01

Recently, in many countries, electric utility industry is undergoing considerable changes in regard to its structure and regulation. It can be clearly seen that the thrust towards privatization and deregulation or re regulation of the electric utility industry will introduce numerous reliability problems that will require new criteria and analytical tools that recognize the residual uncertainties in the new environment. In this paper, different risks and uncertainties in competitive electricity markets are briefly introduced; the approach of customers, operators, planners, generation bodies and network providers to the reliability of deregulated system is studied; the impact of dispersed generation on system reliability is evaluated; and finally, the reliability cost/reliability worth issues in the new competitive environment are considered

COSTS CALCULATION OF TARGET COSTING METHOD

Directory of Open Access Journals (Sweden)

Sebastian UNGUREANU

2014-06-01

Full Text Available Cost information system plays an important role in every organization in the decision making process. An important task of management is ensuring control of the operations, processes, sectors, and not ultimately on costs. Although in achieving the objectives of an organization compete more control systems (production control, quality control, etc., the cost information system is important because monitors results of the other. Detailed analysis of costs, production cost calculation, quantification of losses, estimate the work efficiency provides a solid basis for financial control. Knowledge of the costs is a decisive factor in taking decisions and planning future activities. Managers are concerned about the costs that will appear in the future, their level underpinning the supply and production decisions as well as price policy. An important factor is the efficiency of cost information system in such a way that the information provided by it may be useful for decisions and planning of the work.

Using Length of Stay to Control for Unobserved Heterogeneity When Estimating Treatment Effect on Hospital Costs with Observational Data: Issues of Reliability, Robustness, and Usefulness.

Science.gov (United States)

May, Peter; Garrido, Melissa M; Cassel, J Brian; Morrison, R Sean; Normand, Charles

2016-10-01

To evaluate the sensitivity of treatment effect estimates when length of stay (LOS) is used to control for unobserved heterogeneity when estimating treatment effect on cost of hospital admission with observational data. We used data from a prospective cohort study on the impact of palliative care consultation teams (PCCTs) on direct cost of hospital care. Adult patients with an advanced cancer diagnosis admitted to five large medical and cancer centers in the United States between 2007 and 2011 were eligible for this study. Costs were modeled using generalized linear models with a gamma distribution and a log link. We compared variability in estimates of PCCT impact on hospitalization costs when LOS was used as a covariate, as a sample parameter, and as an outcome denominator. We used propensity scores to account for patient characteristics associated with both PCCT use and total direct hospitalization costs. We analyzed data from hospital cost databases, medical records, and questionnaires. Our propensity score weighted sample included 969 patients who were discharged alive. In analyses of hospitalization costs, treatment effect estimates are highly sensitive to methods that control for LOS, complicating interpretation. Both the magnitude and significance of results varied widely with the method of controlling for LOS. When we incorporated intervention timing into our analyses, results were robust to LOS-controls. Treatment effect estimates using LOS-controls are not only suboptimal in terms of reliability (given concerns over endogeneity and bias) and usefulness (given the need to validate the cost-effectiveness of an intervention using overall resource use for a sample defined at baseline) but also in terms of robustness (results depend on the approach taken, and there is little evidence to guide this choice). To derive results that minimize endogeneity concerns and maximize external validity, investigators should match and analyze treatment and comparison arms

ENABLING USE OF STANDARD COSTING IN LEAN ORGANIZATIONS AS DETERMINANT OF GOAL CONGRUENT BEHAVIOR

DEFF Research Database (Denmark)

Kristensen, Thomas Borup; Israelsen, Poul

2014-01-01

Using the enabling formalization framework in two longitudinal case studies combined with a survey in the companies, we find that a standard costing model can be perceived as a form of enabling formalization in Lean organizations. Hence, standard costing cannot be characterized as coercive...... formalization per se. This contradicts conventional wisdom. Repair is a feature of enabling formalization through the use of standard costing. Applying a structural equation model, we present evidence that this repair feature has a direct effect on behavior that is congruent with Lean objectives. Internal...... and global transparency together with flexibility are three other features of enabling formalization through use of standard costing, but these have an indirect effect on Lean-goal-congruent behavior through the repair feature. Thus, these three features are antecedents of the repair feature, and we also...

Recent Advances in System Reliability Signatures, Multi-state Systems and Statistical Inference

CERN Document Server

Frenkel, Ilia

2012-01-01

Recent Advances in System Reliability discusses developments in modern reliability theory such as signatures, multi-state systems and statistical inference. It describes the latest achievements in these fields, and covers the application of these achievements to reliability engineering practice. The chapters cover a wide range of new theoretical subjects and have been written by leading experts in reliability theory and its applications.  The topics include: concepts and different definitions of signatures (D-spectra),  their  properties and applications  to  reliability of coherent systems and network-type structures; Lz-transform of Markov stochastic process and its application to multi-state system reliability analysis; methods for cost-reliability and cost-availability analysis of multi-state systems; optimal replacement and protection strategy; and statistical inference. Recent Advances in System Reliability presents many examples to illustrate the theoretical results. Real world multi-state systems...

Comparison of mass balance, energy consumption and cost of composting facilities for different types of organic waste

International Nuclear Information System (INIS)

Zhang Huijun; Matsuto, Toshihiko

2011-01-01

Mass balance, energy consumption and cost are basic pieces of information necessary for selecting a waste management technology. In this study, composting facilities that treat different types of organic waste were studied by questionnaire survey and via a chemical analysis of material collected at the facilities. The mass balance was calculated on a dry weight basis because the moisture content of organic waste was very high. Even though the ratio of bulking material to total input varied in the range 0-65% on a dry basis, the carbon and ash content, carbon/nitrogen ratio, heavy metal content and inorganic nutrients in the compost were clearly influenced by the different characteristics of the input waste. The use of bulking material was not correlated with ash or elemental content in the compost. The operating costs were categorised into two groups. There was some economy of scale for wages and maintenance cost, but the costs for electricity and fuel were proportional to the amount of waste. Differences in operating costs can be explained by differences in the process characteristics.

Reliability benefits of dispersed wind resource development

International Nuclear Information System (INIS)

Milligan, M.; Artig, R.

1998-05-01

Generating capacity that is available during the utility peak period is worth more than off-peak capacity. Wind power from a single location might not be available during enough of the peak period to provide sufficient value. However, if the wind power plant is developed over geographically disperse locations, the timing and availability of wind power from these multiple sources could provide a better match with the utility's peak load than a single site. There are other issues that arise when considering disperse wind plant development. Singular development can result in economies of scale and might reduce the costs of obtaining multiple permits and multiple interconnections. However, disperse development can result in cost efficiencies if interconnection can be accomplished at lower voltages or at locations closer to load centers. Several wind plants are in various stages of planning or development in the US. Although some of these are small-scale demonstration projects, significant wind capacity has been developed in Minnesota, with additional developments planned in Wyoming, Iowa and Texas. As these and other projects are planned and developed, there is a need to perform analysis of the value of geographically disperse sites on the reliability of the overall wind plant.This paper uses a production-cost/reliability model to analyze the reliability of several wind sites in the state of Minnesota. The analysis finds that the use of a model with traditional reliability measures does not produce consistent, robust results. An approach based on fuzzy set theory is applied in this paper, with improved results. Using such a model, the authors find that system reliability can be optimized with a mix of disperse wind sites

Reliability of electronic systems

International Nuclear Information System (INIS)

Roca, Jose L.

2001-01-01

Reliability techniques have been developed subsequently as a need of the diverse engineering disciplines, nevertheless they are not few those that think they have been work a lot on reliability before the same word was used in the current context. Military, space and nuclear industries were the first ones that have been involved in this topic, however not only in these environments it is that it has been carried out this small great revolution in benefit of the increase of the reliability figures of the products of those industries, but rather it has extended to the whole industry. The fact of the massive production, characteristic of the current industries, drove four decades ago, to the fall of the reliability of its products, on one hand, because the massively itself and, for other, to the recently discovered and even not stabilized industrial techniques. Industry should be changed according to those two new requirements, creating products of medium complexity and assuring an enough reliability appropriated to production costs and controls. Reliability began to be integral part of the manufactured product. Facing this philosophy, the book describes reliability techniques applied to electronics systems and provides a coherent and rigorous framework for these diverse activities providing a unifying scientific basis for the entire subject. It consists of eight chapters plus a lot of statistical tables and an extensive annotated bibliography. Chapters embrace the following topics: 1- Introduction to Reliability; 2- Basic Mathematical Concepts; 3- Catastrophic Failure Models; 4-Parametric Failure Models; 5- Systems Reliability; 6- Reliability in Design and Project; 7- Reliability Tests; 8- Software Reliability. This book is in Spanish language and has a potentially diverse audience as a text book from academic to industrial courses. (author)

Improved Reliability of Small Molecule Organic Solar Cells by Double Anode Buffer Layers

Directory of Open Access Journals (Sweden)

Pao-Hsun Huang

2014-01-01

Full Text Available An optimized hybrid planar heterojunction (PHJ of small molecule organic solar cells (SM-OSCs based on copper phthalocyanine (CuPc as donor and fullerene (C60 as acceptor was fabricated, which obviously enhanced the performance of device by sequentially using both MoO3 and pentacene as double anode buffer layers (ABL, also known as hole extraction layer (HEL. A series of the vacuum-deposited ABL, acting as an electron and exciton blocking layer, were examined for their characteristics in SM-OSCs. The performance and reliability were compared between conventional ITO/ABL/CuPc/C60/BCP/Ag cells and the new ITO/double ABL/CuPc/C60/BCP/Ag cells. The effect on the electrical properties of these materials was also investigated to obtain the optimal thickness of ABL. The comparison shows that the modified cell has an enhanced reliability compared to traditional cells. The improvement of lifetime was attributed to the idea of double layers to prevent humidity and oxygen from diffusing into the active layer. We demonstrated that the interfacial extraction layers are necessary to avoid degradation of device. That is to say, in normal temperature and pressure, a new avenue for the device within double buffer layers has exhibited the highest values of open circuit voltage (Voc, fill factor (FF, and lifetime in this work compared to monolayer of ABL.

THE PRODUCTION COSTS OF CONVENTIONAL AND ORGANIC APPLE ORCHARDS IN THE VENETO REGION (ITALY)

OpenAIRE

CIMPAN Oana; BEGALLI Diego; CODURRI Stefano

2012-01-01

In times of crisis people are thinking how to make the best choice to be more profitable. Both the manufacturers and the consumers must choose the best solutions for them and their businesses. Making a choice between organic and conventional methods in times of crisis is even more difficult considering production costs and consumption patterns. What is the composition of production costs for an apple orchard, how they can be divided into homogeneous categories and why to choose green are the ...

Establishing a cost model when estimating product cost in early design phases

OpenAIRE

Jeppsson, Johanna; Sjöberg, Jessica

2017-01-01

About 75% of the total product cost is determined in the early design phase, which means that the possibilities to affect costs are relatively small when the design phase is completed. For companies, it is therefore vital to conduct reliable cost estimates in the early design phase, when selecting between different design choices. When conducting a cost estimate there are many uncertainties. The aim with this study is therefore to explore how uncertainties regarding product cost can be consid...

Application of genetic algorithm for reliability allocation in nuclear power plants

International Nuclear Information System (INIS)

Yang, Joon-Eon; Hwang, Mee-Jung; Sung, Tae-Yong; Jin, Youngho

1999-01-01

Reliability allocation is an optimization process of minimizing the total plant costs subject to the overall plant safety goal constraints. Reliability allocation was applied to determine the reliability characteristics of reactor systems, subsystems, major components and plant procedures that are consistent with a set of top-level performance goals; the core melt frequency, acute fatalities and latent fatalities. Reliability allocation can be performed to improve the design, operation and safety of new and/or existing nuclear power plants. Reliability allocation is a kind of a difficult multi-objective optimization problem as well as a global optimization problem. The genetic algorithm, known as one of the most powerful tools for most optimization problems, is applied to the reliability allocation problem of a typical pressurized water reactor in this article. One of the main problems of reliability allocation is defining realistic objective functions. Hence, in order to optimize the reliability of the system, the cost for improving and/or degrading the reliability of the system should be included in the reliability allocation process. We used techniques derived from the value impact analysis to define the realistic objective function in this article

Interactive Reliability-Based Optimal Design

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Thoft-Christensen, Palle; Siemaszko, A.

1994-01-01

Interactive design/optimization of large, complex structural systems is considered. The objective function is assumed to model the expected costs. The constraints are reliability-based and/or related to deterministic code requirements. Solution of this optimization problem is divided in four main...... tasks, namely finite element analyses, sensitivity analyses, reliability analyses and application of an optimization algorithm. In the paper it is shown how these four tasks can be linked effectively and how existing information on design variables, Lagrange multipliers and the Hessian matrix can...

Scoping study on trends in the economic value of electricity reliability to the U.S. economy; TOPICAL

International Nuclear Information System (INIS)

Eto, Joseph; Koomey, Jonathan; Lehman, Bryan; Martin, Nathan; Mills, Evan; Webber, Carrie; Worrell, Ernst

2001-01-01

During the past three years, working with more than 150 organizations representing public and private stakeholders, EPRI has developed the Electricity Technology Roadmap. The Roadmap identifies several major strategic challenges that must be successfully addressed to ensure a sustainable future in which electricity continues to play an important role in economic growth. Articulation of these anticipated trends and challenges requires a detailed understanding of the role and importance of reliable electricity in different sectors of the economy. This report is intended to contribute to that understanding by analyzing key aspects of trends in the economic value of electricity reliability in the U.S. economy. We first present a review of recent literature on electricity reliability costs. Next, we describe three distinct end-use approaches for tracking trends in reliability needs: (1) an analysis of the electricity-use requirements of office equipment in different commercial sectors; (2) an examination of the use of aggregate statistical indicators of industrial electricity use and economic activity to identify high reliability-requirement customer market segments; and (3) a case study of cleanrooms, which is a cross-cutting market segment known to have high reliability requirements. Finally, we present insurance industry perspectives on electricity reliability as an example of a financial tool for addressing customers' reliability needs

Program integration of predictive maintenance with reliability centered maintenance

International Nuclear Information System (INIS)

Strong, D.K. Jr; Wray, D.M.

1990-01-01

This paper addresses improving the safety and reliability of power plants in a cost-effective manner by integrating the recently developed reliability centered maintenance techniques with the traditional predictive maintenance techniques of nuclear power plants. The topics of the paper include a description of reliability centered maintenance (RCM), enhancing RCM with predictive maintenance, predictive maintenance programs, condition monitoring techniques, performance test techniques, the mid-Atlantic Reliability Centered Maintenance Users Group, test guides and the benefits of shared guide development

A Reliability-Oriented Design Method for Power Electronic Converters

DEFF Research Database (Denmark)

Wang, Huai; Zhou, Dao; Blaabjerg, Frede

2013-01-01

Reliability is a crucial performance indicator of power electronic systems in terms of availability, mission accomplishment and life cycle cost. A paradigm shift in the research on reliability of power electronics is going on from simple handbook based calculations (e.g. models in MIL-HDBK-217F h...... and reliability prediction models are provided. A case study on a 2.3 MW wind power converter is discussed with emphasis on the reliability critical component IGBT modules....

Photovoltaic Module Reliability Workshop 2012: February 28 - March 1, 2012

Energy Technology Data Exchange (ETDEWEB)

Kurtz, S.

2013-11-01

NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) 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.

Delivery system characteristics and their association with quality and costs of care: implications for accountable care organizations.

Science.gov (United States)

Chukmaitov, Askar; Harless, David W; Bazzoli, Gloria J; Carretta, Henry J; Siangphoe, Umaporn

2015-01-01

Implementation of accountable care organizations (ACOs) is currently underway, but there is limited empirical evidence on the merits of the ACO model. The aim was to study the associations between delivery system characteristics and ACO competencies, including centralization strategies to manage organizations, hospital integration with physicians and outpatient facilities, health information technology, infrastructure to monitor community health and report quality, and risk-adjusted 30-day all-cause mortality and case-mixed-adjusted inpatient costs for the Medicare population. Panel data (2006-2009) were assembled from Florida and multiple sources: inpatient hospital discharge, vital statistics, the American Hospital Association, the Healthcare Information and Management Systems Society, and other databases. We applied a panel study design, controlling for hospital and market characteristics. Hospitals that were in centralized health systems or became more centralized over the study period had significantly larger reductions in mortality compared with hospitals that remained freestanding. Surprisingly, tightly integrated hospital-physician arrangements were associated with increased mortality; as such, hospitals may wish to proceed cautiously when developing specific types of alignment with local physician organizations. We observed no statistically significant differences in the growth rate of costs across hospitals in any of the health systems studied relative to freestanding hospitals. Although we observed quality improvement in some organizational types, these outcome improvements were not coupled with the additional desired objective of lower cost growth. This implies that additional changes not present during our study period, potentially changes in provider payment approaches, are essential for achieving the ACO objectives of higher quality of care at lower costs. Provider organizations implementing ACOs should consider centralizing service delivery as a

Reliable measurement of the Seebeck coefficient of organic and inorganic materials between 260 K and 460 K

Energy Technology Data Exchange (ETDEWEB)

Beretta, D.; Lanzani, G. [Center for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, via Pascoli 70/3, 20133 Milano (MI) (Italy); Dipartimento di Fisica, P.zza Leonardo da Vinci 32, Politecnico di Milano, 20133 Milano (MI) (Italy); Bruno, P.; Caironi, M., E-mail: mario.caironi@iit.it [Center for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, via Pascoli 70/3, 20133 Milano (MI) (Italy)

2015-07-15

A new experimental setup for reliable measurement of the in-plane Seebeck coefficient of organic and inorganic thin films and bulk materials is reported. The system is based on the “Quasi-Static” approach and can measure the thermopower in the range of temperature between 260 K and 460 K. The system has been tested on a pure nickel bulk sample and on a thin film of commercially available PEDOT:PSS deposited by spin coating on glass. Repeatability within 1.5% for the nickel sample is demonstrated, while accuracy in the measurement of both organic and inorganic samples is guaranteed by time interpolation of data and by operating with a temperature difference over the sample of less than 1 K.

Reliability planning in distributed electric energy systems

Energy Technology Data Exchange (ETDEWEB)

Kahn, E.

1978-10-01

The goal of this paper is to develop tools for technology evaluation that address questions involving the economics of large-scale systems. The kind of cost discussed usually involves some dynamic aspect of the energy system. In particular, such properties as flexibility, stability, and resilience are features of entire systems. Special attention must be paid to the question of reliability, i.e., availability on demand. The storage problem and the planning for reliability in utility systems are the subjects of this paper. The introductory chapter addresses preliminary definitions--reliability planning, uncertainty, resilience, and other sensitivities. The study focuses on the contrast between conventional power generation technologies with controllable output and intermittent resources such as wind and solar electric conversion devices. The system studied is a stylized representation of California conditions. Significant differences were found in reliability planning requirements (and therefore costs) for systems dominated by central station plants as opposed to those dominated by intermittent resource technologies. It is argued that existing hydroelectric facilities need re-optimization. These plants provide the only currently existing bulk power storage in electric energy systems. 38 references. (MCW)

Reliability Oriented Design of a Grid-Connected Photovoltaic Microinverter

DEFF Research Database (Denmark)

Shen, Yanfeng; Wang, Huai; Blaabjerg, Frede

2017-01-01

High reliability performance of microinverters in Photovoltaic (PV) systems is a merit to match lifetime with PV panels, and to reduce the required maintenance efforts and costs. This digest applies a reliability oriented design method for a grid-connected PV microinverter to achieve specific...

Reliability Analysis of Wind Turbines

DEFF Research Database (Denmark)

Toft, Henrik Stensgaard; Sørensen, John Dalsgaard

2008-01-01

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...

Reliability and Maintainability (RAM) Training

Science.gov (United States)

Lalli, Vincent R. (Editor); Malec, Henry A. (Editor); Packard, Michael H. (Editor)

2000-01-01

The theme of this manual is failure physics-the study of how products, hardware, software, and systems fail and what can be done about it. The intent is to impart useful information, to extend the limits of production capability, and to assist in achieving low-cost reliable products. In a broader sense the manual should do more. It should underscore the urgent need CI for mature attitudes toward reliability. Five of the chapters were originally presented as a classroom course to over 1000 Martin Marietta engineers and technicians. Another four chapters and three appendixes have been added, We begin with a view of reliability from the years 1940 to 2000. Chapter 2 starts the training material with a review of mathematics and a description of what elements contribute to product failures. The remaining chapters elucidate basic reliability theory and the disciplines that allow us to control and eliminate failures.

Practice of value-based distribution reliability assessment (VBDRA) at Scarborough Public Utilities

International Nuclear Information System (INIS)

Chen, R-L.

1995-01-01

The development of value-based distribution reliability assessment (VBDRA) at Scarborough Public Utilities was described. Load point reliability indices, customer interruption costs (CIC), continuity and service reliability, accuracy of CIC, and the aspects of application of VBDRA were addressed. The application of VBDRA to a long-term rebuild plan for 4.16 kV distribution system was described. The importance of a cost-benefit analysis for implementation of VBDRA was emphasized. In the case of the Scarborough Public Utilities Commission the enhanced feeder reliability assessment was found to influence the allocation of funding to where it provided the most value to customers. 14 refs., 3 tabs., 3 figs

Comparison of low-cost and engineered materials for phosphorus removal from organic-rich surface water.

Science.gov (United States)

Boyer, Treavor H; Persaud, Amar; Banerjee, Poulomi; Palomino, Pedro

2011-10-15

Excess phosphorus (P) in lakes and rivers remains a major water quality problem on a global scale. As a result, new materials and innovative approaches to P remediation are required. Natural materials and waste byproduct materials from industrial processes have the potential to be effective materials for P removal from surface water. Advantages of natural and waste byproduct materials include their low-cost, abundant supply, and minimal preparation, especially compared with engineered materials, such as ion exchange resins and polymeric adsorbents. As a result, natural and waste byproduct materials are commonly referred to as low-cost materials. Despite the potential advantages of low-cost materials, there are critical gaps in knowledge that are preventing their effective use. In particular, there are limited data on the performance of low-cost materials in surface waters that have high concentrations of natural organic matter (NOM), and there are no systematic studies that track the changes in water chemistry following treatment with low-cost materials or compare their performance with engineered materials. Accordingly, the goal of this work was to evaluate and compare the effectiveness of low-cost and engineered materials for P removal from NOM-rich surface water. Seven low-cost materials and three engineered materials were evaluated using jar tests and mini-column experiments. The test water was a surface water that had a total P concentration of 132-250 μg P/L and a total organic carbon concentration of 15-32 mg C/L. Alum sludge, a byproduct of drinking water treatment, and a hybrid anion exchange resin loaded with nanosize iron oxide were the best performing materials in terms of selective P removal in the presence of NOM and minimum undesirable secondary changes to the water chemistry. Copyright © 2011 Elsevier Ltd. All rights reserved.

Wastewater Treatment Costs and Outlays in Organic Petrochemicals: Standards Versus Taxes With Methodology Suggestions for Marginal Cost Pricing and Analysis

Science.gov (United States)

Thompson, Russell G.; Singleton, F. D., Jr.

1986-04-01

With the methodology recommended by Baumol and Oates, comparable estimates of wastewater treatment costs and industry outlays are developed for effluent standard and effluent tax instruments for pollution abatement in five hypothetical organic petrochemicals (olefins) plants. The computational method uses a nonlinear simulation model for wastewater treatment to estimate the system state inputs for linear programming cost estimation, following a practice developed in a National Science Foundation (Research Applied to National Needs) study at the University of Houston and used to estimate Houston Ship Channel pollution abatement costs for the National Commission on Water Quality. Focusing on best practical and best available technology standards, with effluent taxes adjusted to give nearly equal pollution discharges, shows that average daily treatment costs (and the confidence intervals for treatment cost) would always be less for the effluent tax than for the effluent standard approach. However, industry's total outlay for these treatment costs, plus effluent taxes, would always be greater for the effluent tax approach than the total treatment costs would be for the effluent standard approach. Thus the practical necessity of showing smaller outlays as a prerequisite for a policy change toward efficiency dictates the need to link the economics at the microlevel with that at the macrolevel. Aggregation of the plants into a programming modeling basis for individual sectors and for the economy would provide a sound basis for effective policy reform, because the opportunity costs of the salient regulatory policies would be captured. Then, the government's policymakers would have the informational insights necessary to legislate more efficient environmental policies in light of the wealth distribution effects.

Reliability analysis based on the losses from failures.

Science.gov (United States)

Todinov, M T

2006-04-01

The conventional reliability analysis is based on the premise that increasing the reliability of a system will decrease the losses from failures. On the basis of counterexamples, it is demonstrated that this is valid only if all failures are associated with the same losses. In case of failures associated with different losses, a system with larger reliability is not necessarily characterized by smaller losses from failures. Consequently, a theoretical framework and models are proposed for a reliability analysis, linking reliability and the losses from failures. Equations related to the distributions of the potential losses from failure have been derived. It is argued that the classical risk equation only estimates the average value of the potential losses from failure and does not provide insight into the variability associated with the potential losses. Equations have also been derived for determining the potential and the expected losses from failures for nonrepairable and repairable systems with components arranged in series, with arbitrary life distributions. The equations are also valid for systems/components with multiple mutually exclusive failure modes. The expected losses given failure is a linear combination of the expected losses from failure associated with the separate failure modes scaled by the conditional probabilities with which the failure modes initiate failure. On this basis, an efficient method for simplifying complex reliability block diagrams has been developed. Branches of components arranged in series whose failures are mutually exclusive can be reduced to single components with equivalent hazard rate, downtime, and expected costs associated with intervention and repair. A model for estimating the expected losses from early-life failures has also been developed. For a specified time interval, the expected losses from early-life failures are a sum of the products of the expected number of failures in the specified time intervals covering the

Reliability of the emergency AC power system at nuclear power plants

International Nuclear Information System (INIS)

Battle, R.E.; Campbell, D.J.; Baranowsky, P.W.

1983-01-01

The reliability of the emergency ac power systems typical of most nuclear power plants was estimated, and the cost and increase in reliability for several improvements were estimated. Fault trees were constructed based on a detailed design review of the emergency ac power systems of 18 nuclear plants. The failure probabilities used in the fault trees were calculated from extensive historical data collected from Licensee Event Reports (LERs) and from operating experience information obtained from nuclear plant licensees. No one or two improvements can be made at all plants to significantly increase the industry-average emergency ac power system reliability; rather the most beneficial improvements are varied and plant specific. Improvements in reliability and the associated costs are estimated using plant specific designs and failure probabilities

Fiber Access Networks: Reliability Analysis and Swedish Broadband Market

Science.gov (United States)

Wosinska, Lena; Chen, Jiajia; Larsen, Claus Popp

Fiber access network architectures such as active optical networks (AONs) and passive optical networks (PONs) have been developed to support the growing bandwidth demand. Whereas particularly Swedish operators prefer AON, this may not be the case for operators in other countries. The choice depends on a combination of technical requirements, practical constraints, business models, and cost. Due to the increasing importance of reliable access to the network services, connection availability is becoming one of the most crucial issues for access networks, which should be reflected in the network owner's architecture decision. In many cases protection against failures is realized by adding backup resources. However, there is a trade off between the cost of protection and the level of service reliability since improving reliability performance by duplication of network resources (and capital expenditures CAPEX) may be too expensive. In this paper we present the evolution of fiber access networks and compare reliability performance in relation to investment and management cost for some representative cases. We consider both standard and novel architectures for deployment in both sparsely and densely populated areas. While some recent works focused on PON protection schemes with reduced CAPEX the current and future effort should be put on minimizing the operational expenditures (OPEX) during the access network lifetime.

Investigation of DC-DC Boost Converter for Reliability of Operational Planning

DEFF Research Database (Denmark)

Khazraj, Hesam; Ashouri, Mani; Silva, Filipe Miguel Faria da

2018-01-01

of the interests related to reliability is the power semiconductor switches, which are the most vulnerable elements. The failure of one-power switches can reduce the system reliability. Interleaved technique for DC-DC converters is a redundant strategy to improve the reliability, but at the cost of increasing...

Advanced organics for electronic substrates and packages

CERN Document Server

Fletcher, Andrew E

1992-01-01

Advanced Organics for Electronic Substrates and Packages provides information on packaging, which is one of the most technologically intensive activities in the electronics industry. The electronics packaging community has realized that while semiconductor devices continue to be improved upon for performance, cost, and reliability, it is the interconnection or packaging of these devices that will limit the performance of the systems. Technology must develop packaging for transistor chips, with high levels of performance and integration providing cooling, power, and interconnection, and yet pre

Evaluating the Reliability, Validity, and Usefulness of Education Cost Studies

Science.gov (United States)

Baker, Bruce D.

2006-01-01

Recent studies that purport to estimate the costs of constitutionally adequate education have been described as either a "gold standard" that should guide legislative school finance policy design and judicial evaluation, or as pure "alchemy." Methods for estimating the cost of constitutionally adequate education can be roughly…

Proactive replica checking to assure reliability of data in cloud storage with minimum replication

Science.gov (United States)

Murarka, Damini; Maheswari, G. Uma

2017-11-01

The two major issues for cloud storage systems are data reliability and storage costs. For data reliability protection, multi-replica replication strategy which is used mostly in current clouds acquires huge storage consumption, leading to a large storage cost for applications within the loud specifically. This paper presents a cost-efficient data reliability mechanism named PRCR to cut back the cloud storage consumption. PRCR ensures data reliability of large cloud information with the replication that might conjointly function as a price effective benchmark for replication. The duplication shows that when resembled to the standard three-replica approach, PRCR will scale back to consume only a simple fraction of the cloud storage from one-third of the storage, thence considerably minimizing the cloud storage price.

Organ acquisition cost centers Part I: medicare regulations--truth or consequence.

Science.gov (United States)

Abecassis, M

2006-12-01

Organ Acquisition Cost Centers (OACC) were designed to encourage and incentivize hospitals to provide transplantation services. The purpose of this article (Part I) is to familiarize transplant professionals and transplant center administrators with the regulations that govern OACC. An historical perspective of the evolution of these regulations is necessary to better understand the basic principles underlying this complex area of transplant finance. There is a wide variation in transplant center OACC reporting, suggesting under-reporting by some and overreporting by others. Correct reporting is essential since OACC are auditable. We have surveyed 13 audits by the Office of the Inspector General (OIG) of transplant center OACC in an attempt to identify trends in reporting practices by transplant centers that are not deemed acceptable by the OIG. We discuss these findings in the context of some basic definitions that refer specifically to cost accounting principles necessary for accurate reporting of OACC.

Reliable, Economic, Efficient CO2 Heat Pump Water Heater for North America

Energy Technology Data Exchange (ETDEWEB)

Radcliff, Thomas D; Sienel, Tobias; Huff, Hans-Joachim; Thompson, Adrian; Sadegh, Payman; Olsommer, Benoit; Park, Young

2006-12-31

Adoption of heat pump water heating technology for commercial hot water could save up to 0.4 quads of energy and 5 million metric tons of CO2 production annually in North America, but industry perception is that this technology does not offer adequate performance or reliability and comes at too high of a cost. Development and demonstration of a CO2 heat pump water heater is proposed to reduce these barriers to adoption. Three major themes are addressed: market analysis to understand barriers to adoption, use of advanced reliability models to design optimum qualification test plans, and field testing of two phases of water heater prototypes. Market experts claim that beyond good performance, market adoption requires 'drop and forget' system reliability and a six month payback of first costs. Performance, reliability and cost targets are determined and reliability models are developed to evaluate the minimum testing required to meet reliability targets. Three phase 1 prototypes are designed and installed in the field. Based on results from these trials a product specification is developed and a second phase of five field trial units are built and installed. These eight units accumulate 11 unit-years of service including 15,650 hours and 25,242 cycles of compressor operation. Performance targets can be met. An availability of 60% is achieved and the capability to achieve >90% is demonstrated, but overall reliability is below target, with an average of 3.6 failures/unit-year on the phase 2 demonstration. Most reliability issues are shown to be common to new HVAC products, giving high confidence in mature product reliability, but the need for further work to minimize leaks and ensure reliability of the electronic expansion valve is clear. First cost is projected to be above target, leading to an expectation of 8-24 month payback when substituted for an electric water heater. Despite not meeting all targets, arguments are made that an industry leader could

The design organization test: further demonstration of reliability and validity as a brief measure of visuospatial ability.

Science.gov (United States)

Killgore, William D S; Gogel, Hannah

2014-01-01

Neuropsychological assessments are frequently time-consuming and fatiguing for patients. Brief screening evaluations may reduce test duration and allow more efficient use of time by permitting greater attention toward neuropsychological domains showing probable deficits. The Design Organization Test (DOT) was initially developed as a 2-min paper-and-pencil alternative for the Block Design (BD) subtest of the Wechsler scales. Although initially validated for clinical neurologic patients, we sought to further establish the reliability and validity of this test in a healthy, more diverse population. Two alternate versions of the DOT and the Wechsler Abbreviated Scale of Intelligence (WASI) were administered to 61 healthy adult participants. The DOT showed high alternate forms reliability (r = .90-.92), and the two versions yielded equivalent levels of performance. The DOT was highly correlated with BD (r = .76-.79) and was significantly correlated with all subscales of the WASI. The DOT proved useful when used in lieu of BD in the calculation of WASI IQ scores. Findings support the reliability and validity of the DOT as a measure of visuospatial ability and suggest its potential worth as an efficient estimate of intellectual functioning in situations where lengthier tests may be inappropriate or unfeasible.

The chronic toxicity of molybdate to marine organisms. I. Generating reliable effects data

International Nuclear Information System (INIS)

Heijerick, D.G.; Regoli, L.; Stubblefield, W.

2012-01-01

A scientific research program was initiated by the International Molybdenum Association (IMOA) which addressed identified gaps in the environmental toxicity data for the molybdate ion (MoO 4 2− ). These gaps were previously identified during the preparation of EU-REACH-dossiers for different molybdenum compounds (European Union regulation on Registration, Evaluation, Authorization and Restriction of Chemical substances; EC, 2006). Evaluation of the open literature identified few reliable marine ecotoxicological data that could be used for deriving a Predicted No-Effect Concentration (PNEC) for the marine environment. Rather than calculating a PNEC marine using the assessment factor methodology on a combined freshwater/marine dataset, IMOA decided to generate sufficient reliable marine chronic data to permit derivation of a PNEC by means of the more scientifically robust species sensitivity distribution (SSD) approach (also called the statistical extrapolation approach). Nine test species were chronically exposed to molybdate (added as sodium molybdate dihydrate, Na 2 MoO 4 ·2H 2 O) according to published standard testing guidelines that are acceptable for a broad range of regulatory purposes. The selected test organisms were representative for typical marine trophic levels: micro-algae/diatom (Phaeodactylum tricornutum, Dunaliella tertiolecta), macro-alga (Ceramium tenuicorne), mysids (Americamysis bahia), copepod (Acartia tonsa), fish (Cyprinodon variegatus), echinoderms (Dendraster exentricus, Strongylocentrotus purpuratus) and molluscs (Mytilus edulis, Crassostrea gigas). Available NOEC/EC 10 levels ranged between 4.4 mg Mo/L (blue mussel M. edulis) and 1174 mg Mo/L (oyster C. gigas). Using all available reliable marine chronic effects data that are currently available, a HC 5,50% (median hazardous concentration affecting 5% of the species) of 5.74 (mg Mo)/L was derived with the statistical extrapolation approach, a value that can be used for national and

Cost-Effectiveness of a Model Infection Control Program for Preventing Multi-Drug-Resistant Organism Infections in Critically Ill Surgical Patients.

Science.gov (United States)

Jayaraman, Sudha P; Jiang, Yushan; Resch, Stephen; Askari, Reza; Klompas, Michael

2016-10-01

Interventions to contain two multi-drug-resistant Acinetobacter (MDRA) outbreaks reduced the incidence of multi-drug-resistant (MDR) organisms, specifically methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, and Clostridium difficile in the general surgery intensive care unit (ICU) of our hospital. We therefore conducted a cost-effective analysis of a proactive model infection-control program to reduce transmission of MDR organisms based on the practices used to control the MDRA outbreak. We created a model of a proactive infection control program based on the 2011 MDRA outbreak response. We built a decision analysis model and performed univariable and probabilistic sensitivity analyses to evaluate the cost-effectiveness of the proposed program compared with standard infection control practices to reduce transmission of these MDR organisms. The cost of a proactive infection control program would be $68,509 per year. The incremental cost-effectiveness ratio (ICER) was calculated to be $3,804 per aversion of transmission of MDR organisms in a one-year period compared with standard infection control. On the basis of probabilistic sensitivity analysis, a willingness-to-pay (WTP) threshold of $14,000 per transmission averted would have a 42% probability of being cost-effective, rising to 100% at $22,000 per transmission averted. This analysis gives an estimated ICER for implementing a proactive program to prevent transmission of MDR organisms in the general surgery ICU. To better understand the causal relations between the critical steps in the program and the rate reductions, a randomized study of a package of interventions to prevent healthcare-associated infections should be considered.

The European reliability data system. An organized information exchange on the operation of European nuclear reactors

International Nuclear Information System (INIS)

Mancini, G.; Amesz, J.; Bastianini, P.; Capobianchi, S.

1983-01-01

The paper revises the aims and objectives of the European Reliability Data System (ERDS), a centralized system collecting and organizing, at European level, information related to the operation of LWRs. The ERDS project was started in 1977 and after a preliminary feasibility study that ended in 1979 is now proceeding towards the final design and implementation stages. ERDS exploits information collected in national data systems and information deriving from single reactor sources. The paper describes first the development of the four data banks constituting the system: Component Event Data Bank, CEDB; Abnormal Occurrences Reporting System, AORS; Operating Unit Status Report, OUSR; and Generic Reliability Parameter Data Bank, GRPDB. Several typical aspects concerning the project are then outlined from the need of homogeneization of data and therefore the need for setting up reference classifications, to the problem of data transcoding and input into the system. Furthermore, the need is stressed of involving much more deeply nuclear power plant operators into the process of data acquisition by providing them with a useful feedback from the data analysis. (author)

Fast Reliability Assessing Method for Distribution Network with Distributed Renewable Energy Generation

Science.gov (United States)

Chen, Fan; Huang, Shaoxiong; Ding, Jinjin; Ding, Jinjin; Gao, Bo; Xie, Yuguang; Wang, Xiaoming

2018-01-01

This paper proposes a fast reliability assessing method for distribution grid with distributed renewable energy generation. First, the Weibull distribution and the Beta distribution are used to describe the probability distribution characteristics of wind speed and solar irradiance respectively, and the models of wind farm, solar park and local load are built for reliability assessment. Then based on power system production cost simulation probability discretization and linearization power flow, a optimal power flow objected with minimum cost of conventional power generation is to be resolved. Thus a reliability assessment for distribution grid is implemented fast and accurately. The Loss Of Load Probability (LOLP) and Expected Energy Not Supplied (EENS) are selected as the reliability index, a simulation for IEEE RBTS BUS6 system in MATLAB indicates that the fast reliability assessing method calculates the reliability index much faster with the accuracy ensured when compared with Monte Carlo method.

Mechanical reliability analysis of tubes intended for hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

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

2013-02-15

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.

Improving hospital cost accounting with activity-based costing.

Science.gov (United States)

Chan, Y C

1993-01-01

In this article, activity-based costing, an approach that has proved to be an improvement over the conventional costing system in product costing, is introduced. By combining activity-based costing with standard costing, health care administrators can better plan and control the costs of health services provided while ensuring that the organization's bottom line is healthy.

Implementing a Reliability Centered Maintenance Program at NASA's Kennedy Space Center

National Research Council Canada - National Science Library

Tuttle, Raymond

1998-01-01

.... A reliability centered maintenance (RCM) program seeks to offer equal or greater reliability at decreased cost by insuring only applicable, effective maintenance is performed and by in large part replacing time based maintenance...

77 FR 7526 - Interpretation of Protection System Reliability Standard

Science.gov (United States)

2012-02-13

... Federal Power Act (FPA) requires a Commission-certified Electric Reliability Organization (ERO) to develop.... Cir. 2009). \\8\\ Mandatory Reliability Standards for the Bulk-Power System, Order No. 693, FERC Stats... a person that is ``directly and materially affected'' by Bulk-Power System reliability may request...

Reliability metrics extraction for power electronics converter stressed by thermal cycles

DEFF Research Database (Denmark)

Ma, Ke; Choi, Uimin; Blaabjerg, Frede

2017-01-01

Due to the continuous demands for highly reliable and cost-effective power conversion, the quantified reliability performances of the power electronics converter are becoming emerging needs. The existing reliability modelling approaches for the power electronics converter mainly focuses on the pr...... performance of power electronics system. The final predicted results showed good accuracy with much more reliability information compared to the existing approaches, and the quantified reliability correlation to the mission profiles of converter is mathematically established....

Use of configuration management to reduce development costs in metal parts

International Nuclear Information System (INIS)

Kalsoom, T.; Ahmad, S.

2005-01-01

In development and manufacturing phases of metal parts, design efforts are converted in set of engineering data pack under the given guidelines of Configuration Management (CM). These engineering documents define Configuration Management of metal parts production in a local industry. The development phase is normally less structured and open to Engineering Change Proposals. In our local engineering organizations most of the work done is normally not well documented for future revisions and modernization. This leads to delays in development and increase in production costs of metal parts. This becomes more pronounced if any member of the design team disassociates and leaves the organization. The Configuration Management helps to reduce development costs by providing infrastructure for product identification, documentation, change control, interface control and technical reviews and product audits. Automated or Computer-Assisted CM activities can also be used to shorten response time and increase accuracy and reliability of the produced metal components. (author)

Understanding the cost of power interruptions to U.S. electricity consumers

Energy Technology Data Exchange (ETDEWEB)

LaCommare, Kristina Hamachi; Eto, Joseph H.

2004-09-01

The massive electric power blackout in the northeastern United States and Canada on August 14-15, 2003 resulted in the U.S. electricity system being called ''antiquated'' and catalyzed discussions about modernizing the grid. Industry sources suggested that investments of $50 to $100 billion would be needed. This report seeks to quantify an important piece of information that has been missing from these discussions: how much do power interruptions and fluctuations in power quality (power-quality events) cost U.S. electricity consumers? Accurately estimating this cost will help assess the potential benefits of investments in improving the reliability of the grid. We develop a comprehensive end-use framework for assessing the cost to U.S. electricity consumers of power interruptions and power-quality events (referred to collectively as ''reliability events''). The framework expresses these costs as a function of: (1) Number of customers by type in a region; (2) Frequency and type of reliability events experienced annually (including both power interruptions and power-quality events) by these customers; (3) Cost of reliability events; and (4) Vulnerability of customers to these events. The framework is designed so that its cost estimate can be improved as additional data become available. Using our framework, we estimate that the national cost of power interruptions is about $80 billion annually, based on the best information available in the public domain. However, there are large gaps in and significant uncertainties about the information currently available. Notably, we were not able to develop an estimate of power-quality events. Sensitivity analysis of some of these uncertainties suggests that the total annual cost could range from less than $30 billion to more than $130 billion. Because of this large range and the enormous cost of the decisions that may be based on this estimate, we encourage policy makers, regulators, and

What does an MRI scan cost?

Science.gov (United States)

Young, David W

2015-11-01

Historically, hospital departments have computed the costs of individual tests or procedures using the ratio of cost to charges (RCC) method, which can produce inaccurate results. To determine a more accurate cost of a test or procedure, the activity-based costing (ABC) method must be used. Accurate cost calculations will ensure reliable information about the profitability of a hospital's DRGs.

Reliability assessment for metallized film pulse capacitors with accelerated degradation test

International Nuclear Information System (INIS)

Zhao Jianyin; Liu Fang; Xi Wenjun; He Shaobo; Wei Xiaofeng

2011-01-01

The high energy density self-healing metallized film pulse capacitor has been applied to all kinds of laser facilities for their power conditioning systems, whose reliability is straightforward affected by the reliability level of capacitors. Reliability analysis of highly reliable devices, such as metallized film capacitors, is a challenge due to cost and time restriction. Accelerated degradation test provides a way to predict its life cost and time effectively. A model and analyses for accelerated degradation data of metallized film capacitors are described. Also described is a method for estimating the distribution of failure time. The estimation values of the unknown parameters in this model are 9.066 9 x 10 -8 and 0.022 1. Both the failure probability density function (PDF) and the cumulative distribution function (CDF) can be presented by this degradation failure model. Based on these estimation values and the PDF/CDF, the reliability model of the metallized film capacitors is obtained. According to the reliability model, the probability of the capacitors surviving to 20 000 shot is 0.972 4. (authors)

Carbon-electroluminescence: An organic approach to lighting

Science.gov (United States)

Kumari, Sonali; Chaudhary, Tarun; Chandran, Vivek; Lokeshwari, M.; Shastry, K.

2018-05-01

Over the recent years, quantum dots have garnered massive following and peaked in interest among the scientific community due to their versatility, exotic properties, ease of preparation and low cost. As the demand for faster, reliable and energy efficient electronic devices intensifies, extra emphasis is laid on the development of smart materials capable of satiating this need. Electroluminescent organic quantum dots have emerged as one of the prime contenders in addressing the ecological, economic and technological constraints. Application of such luminescent nanoparticles as fluorescent light converters in LEDs is touted as one of the reliable and easiest avenues in realizing and developing newer energy efficient technologies for the next millennia. One promising candidate is zig-zag graphene quantum dots, which exhibits high electro-luminescence due to a phenomenon known as quantum confinement (where size of the nano-particle is of the same order or less than that of Bohr exciton radius). In this paper, we aim to provide a review of past and present research in the synthesis and development of luminescence using organic quantum dots.

Application of a truncated normal failure distribution in reliability testing

Science.gov (United States)

Groves, C., Jr.

1968-01-01

Statistical truncated normal distribution function is applied as a time-to-failure distribution function in equipment reliability estimations. Age-dependent characteristics of the truncated function provide a basis for formulating a system of high-reliability testing that effectively merges statistical, engineering, and cost considerations.

Cost minimization of generation, storage, and new loads, comparing costs with and without externalities

International Nuclear Information System (INIS)

Noel, Lance; Brodie, Joseph F.; Kempton, Willett; Archer, Cristina L.; Budischak, Cory

2017-01-01

Highlights: • The study models a large regional transmission organization, with various amounts of renewable energy. • The cost of 86 million iterations of energy systems is calculated, with and without externalities. • When including externalities, society should implement 50% renewable energy. - Abstract: The goal of this research is to understand the economics of anticipated large-scale changes in the electric system. 86 million different combinations of renewable generation (wind and solar), natural gas, and three storage types (hydrogen storage, electric vehicles equipped with vehicle-to-grid (V2G) technology, and building heat) are modeled within the PJM Interconnection. The corresponding electric systems are then operated and constrained to meet the load every hour over four years. The total cost of each energy system is calculated, both with and without externalities, to find the least cost energy systems. Using today’s costs of conventional and renewable electricity and without adding any externalities, the cost-minimum system includes no renewable generation, but does include EVs. When externalities are included, however, the most cost-effective to system covers 50% of the electric load with renewable energy and runs reliably without need for either new conventional generation or purpose-built storage. The three novel energy policy implications of this research are: (1) using today’s cost of renewable electricity and estimates of externalities, it is cost effective to implement 240 GW of renewable electricity to meet 50% of the total electric load; (2) there is limited need to construct new natural gas power plants, especially from a system-wide perspective; and (3) existing coal plants may still be useful to the energy system, and instead of being retired, should be repurposed to occasionally provide generation.

Reliability and optimization of structural systems

International Nuclear Information System (INIS)

Thoft-Christensen, P.

1987-01-01

The proceedings contain 28 papers presented at the 1st working conference. The working conference was organized by the IFIP Working Group 7.5. The proceedings also include 4 papers which were submitted, but for various reasons not presented at the working conference. The working conference was attended by 50 participants from 18 countries. The conference was the first scientific meeting of the new IFIP Working Group 7.5 on 'Reliability and Optimization of Structural Systems'. The purpose of the Working Group 7.5 is to promote modern structural system optimization and reliability theory, to advance international cooperation in the field of structural system optimization and reliability theory, to stimulate research, development and application of structural system optimization and reliability theory, to further the dissemination and exchange of information on reliability and optimization of structural system optimization and reliability theory, and to encourage education in structural system optimization and reliability theory. (orig./HP)

An accurate and efficient reliability-based design optimization using the second order reliability method and improved stability transformation method

Science.gov (United States)

Meng, Zeng; Yang, Dixiong; Zhou, Huanlin; Yu, Bo

2018-05-01

The first order reliability method has been extensively adopted for reliability-based design optimization (RBDO), but it shows inaccuracy in calculating the failure probability with highly nonlinear performance functions. Thus, the second order reliability method is required to evaluate the reliability accurately. However, its application for RBDO is quite challenge owing to the expensive computational cost incurred by the repeated reliability evaluation and Hessian calculation of probabilistic constraints. In this article, a new improved stability transformation method is proposed to search the most probable point efficiently, and the Hessian matrix is calculated by the symmetric rank-one update. The computational capability of the proposed method is illustrated and compared to the existing RBDO approaches through three mathematical and two engineering examples. The comparison results indicate that the proposed method is very efficient and accurate, providing an alternative tool for RBDO of engineering structures.

Results of a Demonstration Assessment of Passive System Reliability Utilizing the Reliability Method for Passive Systems (RMPS)

Energy Technology Data Exchange (ETDEWEB)

Bucknor, Matthew; Grabaskas, David; Brunett, Acacia; Grelle, Austin

2015-04-26

Advanced small modular reactor designs include many advantageous design features such as passively driven safety systems that are arguably more reliable and cost effective relative to conventional active systems. Despite their attractiveness, a reliability assessment of passive systems can be difficult using conventional reliability methods due to the nature of passive systems. Simple deviations in boundary conditions can induce functional failures in a passive system, and intermediate or unexpected operating modes can also occur. As part of an ongoing project, Argonne National Laboratory is investigating various methodologies to address passive system reliability. The Reliability Method for Passive Systems (RMPS), a systematic approach for examining reliability, is one technique chosen for this analysis. This methodology is combined with the Risk-Informed Safety Margin Characterization (RISMC) approach to assess the reliability of a passive system and the impact of its associated uncertainties. For this demonstration problem, an integrated plant model of an advanced small modular pool-type sodium fast reactor with a passive reactor cavity cooling system is subjected to a station blackout using RELAP5-3D. This paper discusses important aspects of the reliability assessment, including deployment of the methodology, the uncertainty identification and quantification process, and identification of key risk metrics.

Reliability Engineering Analysis of ATLAS Data Reprocessing Campaigns

CERN Document Server

Vaniachine, A; The ATLAS collaboration; Karpenko, D

2013-01-01

During three years of LHC data taking, the ATLAS collaboration completed three petascale data reprocessing campaigns on the Grid, with up to 2 PB of data being reprocessed every year. In reprocessing on the Grid, failures can occur for a variety of reasons, while Grid heterogeneity makes failures hard to diagnose and repair quickly. As a result, Big Data processing on the Grid must tolerate a continuous stream of failures, errors and faults. While ATLAS fault-tolerance mechanisms improve the reliability of Big Data processing in the Grid, their benefits come at costs and result in delays making the performance prediction difficult. Reliability Engineering provides a framework for fundamental understanding of the Big Data processing on the Grid, which is not a desirable enhancement but a necessary requirement. In ATLAS, cost monitoring and performance prediction became critical for the success of the reprocessing campaigns conducted in preparation for the major physics conferences. In addition, our Reliability...

Reliability Engineering Analysis of ATLAS Data Reprocessing Campaigns

CERN Document Server

Vaniachine, A; The ATLAS collaboration; Karpenko, D

2014-01-01

During three years of LHC data taking, the ATLAS collaboration completed three petascale data reprocessing campaigns on the Grid, with up to 2 PB of data being reprocessed every year. In reprocessing on the Grid, failures can occur for a variety of reasons, while Grid heterogeneity makes failures hard to diagnose and repair quickly. As a result, Big Data processing on the Grid must tolerate a continuous stream of failures, errors and faults. While ATLAS fault-tolerance mechanisms improve the reliability of Big Data processing in the Grid, their benefits come at costs and result in delays making the performance prediction difficult. Reliability Engineering provides a framework for fundamental understanding of the Big Data processing on the Grid, which is not a desirable enhancement but a necessary requirement. In ATLAS, cost monitoring and performance prediction became critical for the success of the reprocessing campaigns conducted in preparation for the major physics conferences. In addition, our Reliability...

Automation of reliability evaluation procedures through CARE - The computer-aided reliability estimation program.

Science.gov (United States)

Mathur, F. P.

1972-01-01

Description of an on-line interactive computer program called CARE (Computer-Aided Reliability Estimation) which can model self-repair and fault-tolerant organizations and perform certain other functions. Essentially CARE consists of a repository of mathematical equations defining the various basic redundancy schemes. These equations, under program control, are then interrelated to generate the desired mathematical model to fit the architecture of the system under evaluation. The mathematical model is then supplied with ground instances of its variables and is then evaluated to generate values for the reliability-theoretic functions applied to the model.

Reliability and Validity of the Turkish Version of Brandes, Dharwadkar, and Dean’s (1999) Organizational Cynicism Scale: The Case of Organized Industrial Zone, Kayseri

OpenAIRE

Karacaoglu, Korhan; Ince, Fatma

2012-01-01

The aim of this research is to investigate the validity and reliability of Turkish version of Organizational Cynicism Scale developed by Brandes et al. (1999). The research was conducted on 300 workers employed in the manufacturing entreprises of Kayseri Organized Industrial Zone. The psychometric properties of the scale were examined by cronbach alpha and item-total corelations for the reliability, and exploratory and confirmatory factor analyses for the validity. As a result of the factor a...

Reliability-Based Optimization of Wind Turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Tarp-Johansen, N.J.

2004-01-01

Reliability-based optimization of the main tower and monopile foundation of an offshore wind turbine is considered. Different formulations are considered of the objective function including benefits and building and failure costs of the wind turbine. Also different reconstruction policies in case...

Network reliability assessment using a cellular automata approach

International Nuclear Information System (INIS)

Rocco S, Claudio M.; Moreno, Jose Ali

2002-01-01

Two cellular automata (CA) models that evaluate the s-t connectedness and shortest path in a network are presented. CA based algorithms enhance the performance of classical algorithms, since they allow a more reliable and straightforward parallel implementation resulting in a dynamic network evaluation, where changes in the connectivity and/or link costs can readily be incorporated avoiding recalculation from scratch. The paper also demonstrates how these algorithms can be applied for network reliability evaluation (based on Monte-Carlo approach) and for finding s-t path with maximal reliability

Sintered tantalum carbide coatings on graphite substrates: Highly reliable protective coatings for bulk and epitaxial growth

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Daisuke; Suzumura, Akitoshi; Shigetoh, Keisuke [Toyota Central R and D Labs., Inc., Nagakute, Aichi 480-1192 (Japan)

2015-02-23

Highly reliable low-cost protective coatings have been sought after for use in crucibles and susceptors for bulk and epitaxial film growth processes involving wide bandgap materials. Here, we propose a production technique for ultra-thick (50–200 μmt) tantalum carbide (TaC) protective coatings on graphite substrates, which consists of TaC slurry application and subsequent sintering processes, i.e., a wet ceramic process. Structural analysis of the sintered TaC layers indicated that they have a dense granular structure containing coarse grain with sizes of 10–50 μm. Furthermore, no cracks or pinholes penetrated through the layers, i.e., the TaC layers are highly reliable protective coatings. The analysis also indicated that no plastic deformation occurred during the production process, and the non-textured crystalline orientation of the TaC layers is the origin of their high reliability and durability. The TaC-coated graphite crucibles were tested in an aluminum nitride (AlN) sublimation growth process, which involves extremely corrosive conditions, and demonstrated their practical reliability and durability in the AlN growth process as a TaC-coated graphite. The application of the TaC-coated graphite materials to crucibles and susceptors for use in bulk AlN single crystal growth, bulk silicon carbide (SiC) single crystal growth, chemical vapor deposition of epitaxial SiC films, and metal-organic vapor phase epitaxy of group-III nitrides will lead to further improvements in crystal quality and reduced processing costs.

Sintered tantalum carbide coatings on graphite substrates: Highly reliable protective coatings for bulk and epitaxial growth

International Nuclear Information System (INIS)

Nakamura, Daisuke; Suzumura, Akitoshi; Shigetoh, Keisuke

2015-01-01

Highly reliable low-cost protective coatings have been sought after for use in crucibles and susceptors for bulk and epitaxial film growth processes involving wide bandgap materials. Here, we propose a production technique for ultra-thick (50–200 μmt) tantalum carbide (TaC) protective coatings on graphite substrates, which consists of TaC slurry application and subsequent sintering processes, i.e., a wet ceramic process. Structural analysis of the sintered TaC layers indicated that they have a dense granular structure containing coarse grain with sizes of 10–50 μm. Furthermore, no cracks or pinholes penetrated through the layers, i.e., the TaC layers are highly reliable protective coatings. The analysis also indicated that no plastic deformation occurred during the production process, and the non-textured crystalline orientation of the TaC layers is the origin of their high reliability and durability. The TaC-coated graphite crucibles were tested in an aluminum nitride (AlN) sublimation growth process, which involves extremely corrosive conditions, and demonstrated their practical reliability and durability in the AlN growth process as a TaC-coated graphite. The application of the TaC-coated graphite materials to crucibles and susceptors for use in bulk AlN single crystal growth, bulk silicon carbide (SiC) single crystal growth, chemical vapor deposition of epitaxial SiC films, and metal-organic vapor phase epitaxy of group-III nitrides will lead to further improvements in crystal quality and reduced processing costs

On reliability and maintenance modelling of ageing equipment in electric power systems

International Nuclear Information System (INIS)

Lindquist, Tommie

2008-04-01

Maintenance optimisation is essential to achieve cost-efficiency, availability and reliability of supply in electric power systems. The process of maintenance optimisation requires information about the costs of preventive and corrective maintenance, as well as the costs of failures borne by both electricity suppliers and customers. To calculate expected costs, information is needed about equipment reliability characteristics and the way in which maintenance affects equipment reliability. The aim of this Ph.D. work has been to develop equipment reliability models taking the effect of maintenance into account. The research has focussed on the interrelated areas of condition estimation, reliability modelling and maintenance modelling, which have been investigated in a number of case studies. In the area of condition estimation two methods to quantitatively estimate the condition of disconnector contacts have been developed, which utilise results from infrared thermography inspections and contact resistance measurements. The accuracy of these methods were investigated in two case studies. Reliability models have been developed and implemented for SF6 circuit-breakers, disconnector contacts and XLPE cables in three separate case studies. These models were formulated using both empirical and physical modelling approaches. To improve confidence in such models a Bayesian statistical method incorporating information from the equipment design process was also developed. This method was illustrated in a case study of SF6 circuit-breaker operating rods. Methods for quantifying the effect of maintenance on equipment condition and reliability have been investigated in case studies on disconnector contacts and SF6 circuit-breakers. The input required by these methods are condition measurements and historical failure and maintenance data, respectively. This research has demonstrated that the effect of maintenance on power system equipment may be quantified using available data

Maximally reliable Markov chains under energy constraints.

Science.gov (United States)

Escola, Sean; Eisele, Michael; Miller, Kenneth; Paninski, Liam

2009-07-01

Signal-to-noise ratios in physical systems can be significantly degraded if the outputs of the systems are highly variable. Biological processes for which highly stereotyped signal generations are necessary features appear to have reduced their signal variabilities by employing multiple processing steps. To better understand why this multistep cascade structure might be desirable, we prove that the reliability of a signal generated by a multistate system with no memory (i.e., a Markov chain) is maximal if and only if the system topology is such that the process steps irreversibly through each state, with transition rates chosen such that an equal fraction of the total signal is generated in each state. Furthermore, our result indicates that by increasing the number of states, it is possible to arbitrarily increase the reliability of the system. In a physical system, however, an energy cost is associated with maintaining irreversible transitions, and this cost increases with the number of such transitions (i.e., the number of states). Thus, an infinite-length chain, which would be perfectly reliable, is infeasible. To model the effects of energy demands on the maximally reliable solution, we numerically optimize the topology under two distinct energy functions that penalize either irreversible transitions or incommunicability between states, respectively. In both cases, the solutions are essentially irreversible linear chains, but with upper bounds on the number of states set by the amount of available energy. We therefore conclude that a physical system for which signal reliability is important should employ a linear architecture, with the number of states (and thus the reliability) determined by the intrinsic energy constraints of the system.

Inter-Rater Reliability and Downstream Financial Implications of Electrocardiography Screening in Young Athletes.

Science.gov (United States)

Dhutia, Harshil; Malhotra, Aneil; Yeo, Tee Joo; Ster, Irina Chis; Gabus, Vincent; Steriotis, Alexandros; Dores, Helder; Mellor, Greg; García-Corrales, Carmen; Ensam, Bode; Jayalapan, Viknesh; Ezzat, Vivienne Anne; Finocchiaro, Gherardo; Gati, Sabiha; Papadakis, Michael; Tome-Esteban, Maria; Sharma, Sanjay

2017-08-01

Preparticipation screening for cardiovascular disease in young athletes with electrocardiography is endorsed by the European Society of Cardiology and several major sporting organizations. One of the concerns of the ECG as a screening test in young athletes relates to the potential for variation in interpretation. We investigated the degree of variation in ECG interpretation in athletes and its financial impact among cardiologists of differing experience. Eight cardiologists (4 with experience in screening athletes) each reported 400 ECGs of consecutively screened young athletes according to the 2010 European Society of Cardiology recommendations, Seattle criteria, and refined criteria. Cohen κ coefficient was used to calculate interobserver reliability. Cardiologists proposed secondary investigations after ECG interpretation, the costs of which were based on the UK National Health Service tariffs. Inexperienced cardiologists were more likely to classify an ECG as abnormal compared with experienced cardiologists (odds ratio, 1.44; 95% confidence interval, 1.03-2.02). Modification of ECG interpretation criteria improved interobserver reliability for categorizing an ECG as abnormal from poor (2010 European Society of Cardiology recommendations; κ=0.15) to moderate (refined criteria; κ=0.41) among inexperienced cardiologists; however, interobserver reliability was moderate for all 3 criteria among experienced cardiologists (κ=0.40-0.53). Inexperienced cardiologists were more likely to refer athletes for further evaluation compared with experienced cardiologists (odds ratio, 4.74; 95% confidence interval, 3.50-6.43) with poorer interobserver reliability (κ=0.22 versus κ=0.47). Interobserver reliability for secondary investigations after ECG interpretation ranged from poor to fair among inexperienced cardiologists (κ=0.15-0.30) and fair to moderate among experienced cardiologists (κ=0.21-0.46). The cost of cardiovascular evaluation per athlete was $175 (95

A methodology based in particle swarm optimization algorithm for preventive maintenance focused in reliability and cost

International Nuclear Information System (INIS)

Luz, Andre Ferreira da

2009-01-01

In this work, a Particle Swarm Optimization Algorithm (PSO) is developed for preventive maintenance optimization. The proposed methodology, which allows the use flexible intervals between maintenance interventions, instead of considering fixed periods (as usual), allows a better adaptation of scheduling in order to deal with the failure rates of components under aging. Moreover, because of this flexibility, the planning of preventive maintenance becomes a difficult task. Motivated by the fact that the PSO has proved to be very competitive compared to other optimization tools, this work investigates the use of PSO as an alternative tool of optimization. Considering that PSO works in a real and continuous space, it is a challenge to use it for discrete optimization, in which scheduling may comprise variable number of maintenance interventions. The PSO model developed in this work overcome such difficulty. The proposed PSO searches for the best policy for maintaining and considers several aspects, such as: probability of needing repair (corrective maintenance), the cost of such repairs, typical outage times, costs of preventive maintenance, the impact of maintaining the reliability of systems as a whole, and the probability of imperfect maintenance. To evaluate the proposed methodology, we investigate an electro-mechanical system consisting of three pumps and four valves, High Pressure Injection System (HPIS) of a PWR. Results show that PSO is quite efficient in finding the optimum preventive maintenance policies for the HPIS. (author)

Standards in reliability and safety engineering

International Nuclear Information System (INIS)

O'Connor, Patrick

1998-01-01

This article explains how the highest 'world class' levels of reliability and safety are achieved, by adherence to the basic principles of excellence in design, production, support and maintenance, by continuous improvement, and by understanding that excellence and improvement lead to reduced costs. These principles are contrasted with the methods that have been developed and standardised, particularly military standards for reliability, ISO9000, and safety case regulations. The article concludes that the formal, standardised approaches are misleading and counterproductive, and recommends that they be replaced by a philosophy based on the realities of human performance

System reliability with correlated components: Accuracy of the Equivalent Planes method

NARCIS (Netherlands)

Roscoe, K.; Diermanse, F.; Vrouwenvelder, A.C.W.M.

2015-01-01

Computing system reliability when system components are correlated presents a challenge because it usually requires solving multi-fold integrals numerically, which is generally infeasible due to the computational cost. In Dutch flood defense reliability modeling, an efficient method for computing

System reliability with correlated components : Accuracy of the Equivalent Planes method

NARCIS (Netherlands)

Roscoe, K.; Diermanse, F.; Vrouwenvelder, T.

2015-01-01

Computing system reliability when system components are correlated presents a challenge because it usually requires solving multi-fold integrals numerically, which is generally infeasible due to the computational cost. In Dutch flood defense reliability modeling, an efficient method for computing

Reliability Assessment of Offshore Wind Turbines Considering Faults of Electrical / Mechanical Components

DEFF Research Database (Denmark)

Kostandyan, Erik; Sørensen, John Dalsgaard

2013-01-01

For offshore wind turbines, the cost contribution to Cost of Energy from inspections and Operation & Maintenance can be substantial, and can be expected to increase when wind farms are placed at deeper water depths, further from the coast and in more harsh environments. Estimates of the reliability...... is considered and related to reliability estimation by taking into account faults e.g. due to failure of an electrical component or loss of grid....

Basic factors to forecast maintenance cost and failure processes for nuclear power plants

International Nuclear Information System (INIS)

Popova, Elmira; Yu, Wei; Kee, Ernie; Sun, Alice; Richards, Drew; Grantom, Rick

2006-01-01

Two types of maintenance interventions are usually administered at nuclear power plants: planned and corrective. The cost incurred includes the labor (manpower) cost, cost for new parts, or emergency order of expensive items. At the plant management level there is a budgeted amount of money to be spent every year for such operations. It is very important to have a good forecast for this cost since unexpected events can trigger it to a very high level. In this research we present a statistical factor model to forecast the maintenance cost for the incoming month. One of the factors is the expected number of unplanned (due to failure) maintenance interventions. We introduce a Bayesian model for the failure rate of the equipment, which is input to the cost forecasting model. The importance of equipment reliability and prediction in the commercial nuclear power plant is presented along with applicable governmental and industry organization requirements. A detailed statistical analysis is performed on a set of maintenance cost and failure data gathered at the South Texas Project Nuclear Operating Company (STPNOC) in Bay City, Texas, USA

Non-periodic preventive maintenance with reliability thresholds for complex repairable systems

International Nuclear Information System (INIS)

Lin, Zu-Liang; Huang, Yeu-Shiang; Fang, Chih-Chiang

2015-01-01

In general, a non-periodic condition-based PM policy with different condition variables is often more effective than a periodic age-based policy for deteriorating complex repairable systems. In this study, system reliability is estimated and used as the condition variable, and three reliability-based PM models are then developed with consideration of different scenarios which can assist in evaluating the maintenance cost for each scenario. The proposed approach provides the optimal reliability thresholds and PM schedules in advance by which the system availability and quality can be ensured and the organizational resources can be well prepared and managed. The results of the sensitivity anlysis indicate that PM activities performed at a high reliability threshold can not only significantly improve the system availability but also efficiently extend the system lifetime, although such a PM strategy is more costly than that for a low reliabiltiy threshold. The optimal reliability threshold increases along with the number of PM activities to prevent future breakdowns caused by severe deterioration, and thus substantially reduces repair costs. - Highlights: • The PM problems for repairable deteriorating systems are formulated. • The structural properties of the proposed PM models are investigated. • The corresponding algorithms to find the optimal PM strategies are provided. • Imperfect PM activities are allowed to reduce the occurences of breakdowns. • Provide managers with insights about the critical factors in the planning stage

10 CFR 600.317 - Allowable costs.

Science.gov (United States)

2010-01-01

... to the type of entity incurring the cost as follows: (1) For-profit organizations. Allowability of costs incurred by for-profit organizations and those nonprofit organizations listed in Attachment C to... specifically authorized in the award document. (2) Other types of organizations. Allowability of costs incurred...

Efficiency and cost optimization of a regenerative Organic Rankine Cycle power plant through the multi-objective approach

International Nuclear Information System (INIS)

Gimelli, A.; Luongo, A.; Muccillo, M.

2017-01-01

Highlights: • Multi-objective optimization method for ORC design has been addressed. • Trade-off between electric efficiency and overall heat exchangers area is evaluated. • The heat exchangers area was used as objective function to minimize the plant cost. • MDM was considered as organic working fluid for the thermodynamic cycle. • Electric efficiency: 14.1–18.9%. Overall heat exchangers area: 446–1079 m 2 . - Abstract: Multi-objective optimization could be, in the industrial sector, a fundamental strategic approach for defining the target design specifications and operating parameters of new competitive products for the market, especially in renewable energy and energy savings fields. Vector optimization mostly enabled the determination of a set of optimal solutions characterized by different costs, sizes, efficiencies and other key features. The designer can subsequently select the solution with the best compromise between the objective functions for the specific application and constraints. In this paper, a multi-objective optimization problem addressing an Organic Rankine Cycle system is solved with consideration for the electric efficiency and overall heat exchangers area as quantities that should be optimized. In fact, considering that the overall capital cost of the ORC system is dominated by the cost of the heat exchangers rather than that of the pump and turbine, this area is related to the cost of the plant and so it was used to indirectly optimize the economic system performance. For this reason, although cost data have not been used, the heat exchangers area was used as a second objective function to minimize the plant cost. Pareto optimal solutions highlighted a trade-off between the two conflicting objective functions. Octamethyltrisiloxane (MDM) was considered organic working fluid, while the following input parameters were used as decision variables: minimum and maximum pressure of the thermodynamic cycle; superheating and subcooling

Sequential optimization and reliability assessment method for metal forming processes

International Nuclear Information System (INIS)

Sahai, Atul; Schramm, Uwe; Buranathiti, Thaweepat; Chen Wei; Cao Jian; Xia, Cedric Z.

2004-01-01

Uncertainty is inevitable in any design process. The uncertainty could be due to the variations in geometry of the part, material properties or due to the lack of knowledge about the phenomena being modeled itself. Deterministic design optimization does not take uncertainty into account and worst case scenario assumptions lead to vastly over conservative design. Probabilistic design, such as reliability-based design and robust design, offers tools for making robust and reliable decisions under the presence of uncertainty in the design process. Probabilistic design optimization often involves double-loop procedure for optimization and iterative probabilistic assessment. This results in high computational demand. The high computational demand can be reduced by replacing computationally intensive simulation models with less costly surrogate models and by employing Sequential Optimization and reliability assessment (SORA) method. The SORA method uses a single-loop strategy with a series of cycles of deterministic optimization and reliability assessment. The deterministic optimization and reliability assessment is decoupled in each cycle. This leads to quick improvement of design from one cycle to other and increase in computational efficiency. This paper demonstrates the effectiveness of Sequential Optimization and Reliability Assessment (SORA) method when applied to designing a sheet metal flanging process. Surrogate models are used as less costly approximations to the computationally expensive Finite Element simulations

The chronic toxicity of molybdate to marine organisms. I. Generating reliable effects data

Energy Technology Data Exchange (ETDEWEB)

Heijerick, D.G., E-mail: Dagobert.heijerick@arche-consulting.be [ARCHE - Assessing Risks of Chemicals, Stapelplein 70 Bus 104, Gent (Belgium); Regoli, L. [International Molybdenum Association, 4 Heathfield Terrace, London, W4 4JE (United Kingdom); Stubblefield, W. [Oregon State University, Department of Environmental and Molecular Toxicology, 421 Weniger Hall, Corvallis, OR 97331 (United States)

2012-07-15

A scientific research program was initiated by the International Molybdenum Association (IMOA) which addressed identified gaps in the environmental toxicity data for the molybdate ion (MoO{sub 4}{sup 2-}). These gaps were previously identified during the preparation of EU-REACH-dossiers for different molybdenum compounds (European Union regulation on Registration, Evaluation, Authorization and Restriction of Chemical substances; EC, 2006). Evaluation of the open literature identified few reliable marine ecotoxicological data that could be used for deriving a Predicted No-Effect Concentration (PNEC) for the marine environment. Rather than calculating a PNEC{sub marine} using the assessment factor methodology on a combined freshwater/marine dataset, IMOA decided to generate sufficient reliable marine chronic data to permit derivation of a PNEC by means of the more scientifically robust species sensitivity distribution (SSD) approach (also called the statistical extrapolation approach). Nine test species were chronically exposed to molybdate (added as sodium molybdate dihydrate, Na{sub 2}MoO{sub 4}{center_dot}2H{sub 2}O) according to published standard testing guidelines that are acceptable for a broad range of regulatory purposes. The selected test organisms were representative for typical marine trophic levels: micro-algae/diatom (Phaeodactylum tricornutum, Dunaliella tertiolecta), macro-alga (Ceramium tenuicorne), mysids (Americamysis bahia), copepod (Acartia tonsa), fish (Cyprinodon variegatus), echinoderms (Dendraster exentricus, Strongylocentrotus purpuratus) and molluscs (Mytilus edulis, Crassostrea gigas). Available NOEC/EC{sub 10} levels ranged between 4.4 mg Mo/L (blue mussel M. edulis) and 1174 mg Mo/L (oyster C. gigas). Using all available reliable marine chronic effects data that are currently available, a HC{sub 5,50%} (median hazardous concentration affecting 5% of the species) of 5.74 (mg Mo)/L was derived with the statistical extrapolation approach, a

Bypassing BDD Construction for Reliability Analysis

DEFF Research Database (Denmark)

Williams, Poul Frederick; Nikolskaia, Macha; Rauzy, Antoine

2000-01-01

In this note, we propose a Boolean Expression Diagram (BED)-based algorithm to compute the minimal p-cuts of boolean reliability models such as fault trees. BEDs make it possible to bypass the Binary Decision Diagram (BDD) construction, which is the main cost of fault tree assessment....

Coordination pays off: a comparison of two models for organizing hip fracture care, outcomes and costs.

Science.gov (United States)

Löfgren, Susanne; Rehnberg, Clas; Ljunggren, Gunnar; Brommels, Mats

2015-01-01

With the "graying" of the population, hip fractures place an increasing burden on health systems and call for efficient forms of care. The aim was to compare two models of organizing hip fracture care at one university hospital working at two sites. The differences in organization were coordinated care provided in one of the sites and traditional care, divided between different institutions, in the other. The study was conducted at a Swedish university hospital and included all 503 hip fracture patients, admitted during the 1-year period of February 2009 through January 2010. Patient gender, age, type of fracture, admission and discharge dates were documented. The patients were surveyed of their health-related quality of life at the time of admission and at 4 and 12 months after discharge. The costs for the inpatient care episode were estimated using three costing methods. The coordinated care model resulted in a shorter hospital stay and consistently lower costs. There was no difference between patient-reported quality of life. The care of hip fracture patients coordinated by a geriatric ward throughout the whole care episode is more cost-efficient than uncoordinated where patients are transferred to other institutions for rehabilitation. © 2014 The Authors. The International Journal of Health Planning and Management published by John Wiley & Sons Ltd.

Cost-effectiveness of policies aimed at increasing organ donation: the case of Chile.

Science.gov (United States)

Domínguez, J; Harrison, R; Atal, R; Larraín, L

2013-01-01

In this article we present an economic evaluation of policies aimed at increasing deceased organ donation in Chile, a developing country that has low donation rates; it had 5.4 donors per million people (pmp) in 2010. Expert opinions of leading participants in donation and transplantation were analyzed, resulting in a set of local policies aimed at increasing donation rates. Using previous results of reported cost savings of increasing kidney transplantation in Chile, we estimated the net benefits of these policies, as a function of additional donors. The main problem of the Chilean system seems to be the low capability to identify potential donors and a deficit in intensive care unit (ICU) beds. Among considered policies central to increase donation are the following: increasing human and capital resources dedicated to identifying potential donors, providing ICU beds from private centers, and developing an online information system that facilitates procurement coordination and the evaluation of performance at each hospital. Our results show that there is a linear relationship between cost savings and incremental donors pmp. For example, if these policies are capable of elevating donation rates in Chile by 6 donors pmp net estimated cost savings are approximately US $1.9 million. Likewise, considering the effect on patients' quality of life, savings would amount to around $15.0 million dollars per year. Our estimates suggest that these policies have a large cost-saving potential. In fact, considering implementation costs, cost reduction is positive after 4 additional donors pmp, and increasing afterward. Copyright © 2013 Elsevier Inc. All rights reserved.

Computer-aided reliability and risk assessment

International Nuclear Information System (INIS)

Leicht, R.; Wingender, H.J.

1989-01-01

Activities in the fields of reliability and risk analyses have led to the development of particular software tools which now are combined in the PC-based integrated CARARA system. The options available in this system cover a wide range of reliability-oriented tasks, like organizing raw failure data in the component/event data bank FDB, performing statistical analysis of those data with the program FDA, managing the resulting parameters in the reliability data bank RDB, and performing fault tree analysis with the fault tree code FTL or evaluating the risk of toxic or radioactive material release with the STAR code. (orig.)

Centralized Reliability Data Organization (CREDO) assessment of critical component unavailability in liquid metal reactors

International Nuclear Information System (INIS)

Koger, K.H.; Haire, M.J.; Humphrys, B.L.; Manneschmidt, J.F.; Setoguchi, K.; Nakai, R.

1988-01-01

The Centralized Reliability Data Organization (CREDO) is the largest repository of liquid metal reactor (LMR) component reliability data in the world. It is jointly sponsored by the US Dept. of Energy (DOE) and the Power Reactor and Nuclear Fuel Development Corporation (PNC) of Japan. The CREDO data base contains information on a population of more than 20,000 components and approximately 1500 event records. A conservative estimation is that the total component operating hours is approaching 2.2 billion hours. The work reported here focuses on the availability information contained in CREDO and the development of availability critical items lists. That is, individual components are ranked in prioritized lists from worst to best performers from an availability standpoint. Availability as used here is an inherent characteristics of the component and is not necessarily related to plant operability. A major observation is that a few components have a much higher unavailability factor than the average. The top fifteen components contribute 93%, 77%, and 87% of the total system unavailability for EBR-II, FFTF, and JOYO respectively. Critical components common to all three sites are mechanical pumps and electromagnetic pumps. Application of resources to these components with the highest unavailability will have the greatest effect on overall availability. All three sites demonstrate that low maintainability (i.e., long repair times), rather than unreliability (i.e., high failure rates), are the main contributors, by about a two-to-one margin, to liquid metal system unavailability

La confiabilidad integral del activo. // The reliability of a physical asset.

Directory of Open Access Journals (Sweden)

L. F. Sexto Cabrera

2008-01-01

Full Text Available En el presente artículo se discute sobre algunos aspectos que influyen sobre la confiabilidad de un activo físico. En él seproponen diferentes clasificaciones de fallos. Se presentan algunos elementos sobre el análisis de la confiabilidad humana ylos tipos de errores. De manera introductoria se comenta acerca de los defectos crónicos tolerados y el modelo de la trilogíade Juran. Se presentan reflexiones acerca de los procesos de deterioro gradual que puede sufrir un activo cualquiera.Finalmente, se discute sobre los costos de la confiabilidad.Palabras claves: Confiabilidad, fallo, modo de fallo, defectos crónicos, confiabilidad humana, costos de laconfiabilidad.____________________________________________________________________________Abstract.This paper discusses some aspects that influence about the reliability of a physical asset. Is presented differentclassifications of failures. Some elements are proposed about the analysis of the human reliability and the types of errors, aswell as, an introduction about the tolerated chronic defects and the Juran trilogy. Reflections are presented about theprocesses of gradual deterioration. Finally, is discusses on the reliability costs.Key words; Reliability, failure, failure mode, chronic defects, human reliability, reliability costs.

Nuclear power production: The financial costs. Background paper

International Nuclear Information System (INIS)

Berg, P.

1993-11-01

For many years, the Canadian nuclear industry has priced itself on its ability to provide safe, reliable and low-cost electricity to consumers. While nuclear power has indeed proved to be a relatively safe generator of electricity, its performance with respect to reliability and cost has declined noticeably in recent years. This paper documents the deteriorating cost performance of the industry, in comparison with that of its traditional competitor in power generation. It also breaks down the total costs into its component parts, assessing the key factors underlying the trends that are worsening the competitive position of the industry: a rise in initial capital costs, unanticipated technical difficulties resulting in additional capital costs, and the increasing operating expenses associated with poorer-than-expected reactor performance. (author). 8 refs., 2 tabs., 1 fig

Reliability of supply in competitive electricity markets: The Nordic electricity Market

International Nuclear Information System (INIS)

Singh, Balbir

2005-12-01

An overview of the current regulation and performance of the network utilities with respect to the reliability of supply across Europe in general indicates wide variation. On the regional level the situation in the Nordic market is no exception. Can the variation in reliability of supply in Nordic region be explained by differences in regulatory frameworks in the Nordic countries and is it possible to draw any best practice lessons for other countries and regions? The Norwegian regulation and performance with respect to reliability criterion is encouraging, however it must be emphasized that the Norwegian experience with reliability regulation in its current form covers a period of 3 years, a period that is too short to evaluate the Norwegian model. A closer examination of the Norwegian model reveals dynamic trade off in reliability performance, which if permanent may endanger the reliability of supply in the long-run. Last, but not the least important is the criterion that choice of regulation should be based on a careful social cost-benefit analysis of the regulatory model where both cost incurred by the regulatory agencies and the compliance costs incurred by the regulated utilities are included. A preliminary analysis of regulatory agencies in the Nordic market indicates that Norwegian model of network regulation is quite resource incentive. While it is premature to draw conclusions about the national regulatory mechanisms, the Nordic cross border regulation through voluntary arrangements under the auspices of NORDEL provides a good example of an arrangement that is useful when implementation of a formal regulatory regime across different jurisdiction is not possible

Reliability-Based Structural Optimization of Wave Energy Converters

Directory of Open Access Journals (Sweden)

Simon Ambühl

2014-12-01

Full Text Available More and more wave energy converter (WEC concepts are reaching prototypelevel. Once the prototype level is reached, the next step in order to further decrease thelevelized cost of energy (LCOE is optimizing the overall system with a focus on structuraland maintenance (inspection costs, as well as on the harvested power from the waves.The target of a fully-developed WEC technology is not maximizing its power output,but minimizing the resulting LCOE. This paper presents a methodology to optimize thestructural design of WECs based on a reliability-based optimization problem and the intentto maximize the investor’s benefits by maximizing the difference between income (e.g., fromselling electricity and the expected expenses (e.g., structural building costs or failure costs.Furthermore, different development levels, like prototype or commercial devices, may havedifferent main objectives and will be located at different locations, as well as receive varioussubsidies. These points should be accounted for when performing structural optimizationsof WECs. An illustrative example on the gravity-based foundation of the Wavestar deviceis performed showing how structural design can be optimized taking target reliability levelsand different structural failure modes due to extreme loads into account.

Reliability engineering analysis of ATLAS data reprocessing campaigns

International Nuclear Information System (INIS)

Vaniachine, A; Golubkov, D; Karpenko, D

2014-01-01

During three years of LHC data taking, the ATLAS collaboration completed three petascale data reprocessing campaigns on the Grid, with up to 2 PB of data being reprocessed every year. In reprocessing on the Grid, failures can occur for a variety of reasons, while Grid heterogeneity makes failures hard to diagnose and repair quickly. As a result, Big Data processing on the Grid must tolerate a continuous stream of failures, errors and faults. While ATLAS fault-tolerance mechanisms improve the reliability of Big Data processing in the Grid, their benefits come at costs and result in delays making the performance prediction difficult. Reliability Engineering provides a framework for fundamental understanding of the Big Data processing on the Grid, which is not a desirable enhancement but a necessary requirement. In ATLAS, cost monitoring and performance prediction became critical for the success of the reprocessing campaigns conducted in preparation for the major physics conferences. In addition, our Reliability Engineering approach supported continuous improvements in data reprocessing throughput during LHC data taking. The throughput doubled in 2011 vs. 2010 reprocessing, then quadrupled in 2012 vs. 2011 reprocessing. We present the Reliability Engineering analysis of ATLAS data reprocessing campaigns providing the foundation needed to scale up the Big Data processing technologies beyond the petascale.

Reliability enhancement through optimal burn-in

Science.gov (United States)

Kuo, W.

1984-06-01

A numerical reliability and cost model is defined for production line burn-in tests of electronic components. The necessity of burn-in is governed by upper and lower bounds: burn-in is mandatory for operation-critical or nonreparable component; no burn-in is needed when failure effects are insignificant or easily repairable. The model considers electronic systems in terms of a series of components connected by a single black box. The infant mortality rate is described with a Weibull distribution. Performance reaches a steady state after burn-in, and the cost of burn-in is a linear function for each component. A minimum cost is calculated among the costs and total time of burn-in, shop repair, and field repair, with attention given to possible losses in future sales from inadequate burn-in testing.

Power quality and reliability issues in a deregulated energy market

International Nuclear Information System (INIS)

Huggins, M.J.

1999-01-01

The challenge of maintaining power quality and reliability in Ontario's new competitive electricity market was the focus of this paper. The intention of Ontario's deregulation is to lower costs and give customers more power and choice. However, some fear that costs pressures may lead to poorer quality. This paper reviewed the causes, costs, and responsibilities, and made some suggestions concerning how customers can protect their interests as the market opens. It was suggested that in order to assure power quality, especially during the transition period, customers need to take care to design their systems and equipment to tolerate some quality variations. Conversely, utilities need to strive for at least minimum industry standards under most conditions. Contracts should be carefully crafted, with responsibilities for reliability and quality clearly stated. 2 refs

Constructing the Best Reliability Data for the Job

Science.gov (United States)

Kleinhammer, R. K.; Kahn, J. C.

2014-01-01

Modern business and technical decisions are based on the results of analyses. When considering assessments using "reliability data", the concern is how long a system will continue to operate as designed. Generally, the results are only as good as the data used. Ideally, a large set of pass/fail tests or observations to estimate the probability of failure of the item under test would produce the best data. However, this is a costly endeavor if used for every analysis and design. Developing specific data is costly and time consuming. Instead, analysts rely on available data to assess reliability. Finding data relevant to the specific use and environment for any project is difficult, if not impossible. Instead, we attempt to develop the "best" or composite analog data to support our assessments. One method used incorporates processes for reviewing existing data sources and identifying the available information based on similar equipment, then using that generic data to derive an analog composite. Dissimilarities in equipment descriptions, environment of intended use, quality and even failure modes impact the "best" data incorporated in an analog composite. Once developed, this composite analog data provides a "better" representation of the reliability of the equipment or component can be used to support early risk or reliability trade studies, or analytical models to establish the predicted reliability data points. Data that is more representative of reality and more project specific would provide more accurate analysis, and hopefully a better final decision.

Constructing the "Best" Reliability Data for the Job

Science.gov (United States)

DeMott, D. L.; Kleinhammer, R. K.

2014-01-01

Modern business and technical decisions are based on the results of analyses. When considering assessments using "reliability data", the concern is how long a system will continue to operate as designed. Generally, the results are only as good as the data used. Ideally, a large set of pass/fail tests or observations to estimate the probability of failure of the item under test would produce the best data. However, this is a costly endeavor if used for every analysis and design. Developing specific data is costly and time consuming. Instead, analysts rely on available data to assess reliability. Finding data relevant to the specific use and environment for any project is difficult, if not impossible. Instead, we attempt to develop the "best" or composite analog data to support our assessments. One method used incorporates processes for reviewing existing data sources and identifying the available information based on similar equipment, then using that generic data to derive an analog composite. Dissimilarities in equipment descriptions, environment of intended use, quality and even failure modes impact the "best" data incorporated in an analog composite. Once developed, this composite analog data provides a "better" representation of the reliability of the equipment or component can be used to support early risk or reliability trade studies, or analytical models to establish the predicted reliability data points. Data that is more representative of reality and more project specific would provide more accurate analysis, and hopefully a better final decision.

COST-BENEFIT ANALYSIS OF BIOCONVERSION NEUFCHATEL WHEY INTO RECTIFIED ETHANOL AND ORGANIC LIQUID FERTILIZER IN SEMI PILOT SCALE

Directory of Open Access Journals (Sweden)

Gemilang Lara UTAMA

2015-10-01

Full Text Available Aims of the study was to determine the cost-benefit analysis in neufchatel whey bioconversion into rectified ethanol and organic liquid fertilizer. Bioconversion whey into rectified ethanol and organic liquid fertilizer has shown great potential as a way to reduce the pollution resulting from cheese-making process. Semi pilot scale experiment was done to ferment 5 L neufchatel whey using 5% K. lactis at 33°C for 24 h in semi anaerobic plastic container without agitation and then distilled into 96.2% purity. Data collected and analyzed descriptively related to benefit cost ratio/BCR, net present value/NPV and internal rate returns/IRR. The result showed that semi pilot scale bioconversion of neufchatel whey resulting in 106.42 ml rectified ethanol and 4404.22 ml distillery residue. Economic benefit could achieved by the support of distillery residue sales as organic liquid fertilizer.

Power system reliability impacts of wind generation and operational reserve requirements

Directory of Open Access Journals (Sweden)

Esteban Gil

2015-06-01

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.

Managing costs at Ginna Station

International Nuclear Information System (INIS)

Mecredy, R.C.

1990-01-01

A nuclear power plant with a capital cost of $88 million and an annual operations and maintenance (O and M) cost of $3.2 million that is operated by a plant staff of 59 people? The Ginna nuclear power plant was indeed such a plant in 1970, its first full year of operation. Today that same plant has a total invested capital cost of $400 million with an annual capital cost, including upgrade projects which are being amortized, of $37 million. The annual O and M expenditure is nearly $60 million, and the total staffing, both plant and corporate support, is nearly 600 people. The result of this increased cost has been a dramatic narrowing of the cost margin between Ginna and coal units in the rochester Gas and Electric system. While increased expenditures have resulted in improved reliability and operability, and have increased the margins of safety, it is becoming necessary to implement cost monitoring and control measures so that each dollar spent provides maximum value. The factors which have contributed to the increased capital and O and M expenditures are well known. They include a broad range of safety, reliability, and operating projects and activities. Current upward pressures on cost include initiatives such as procurement control, procedure upgrades, configuration management, enhanced maintenance activities, and equipment replacements and upgrades

Reliability implications for commercial Plowshare applications

Energy Technology Data Exchange (ETDEWEB)

Brumleve, T D [Plowshare Systems Research Division, Sandia Laboratories, Livermore, CA (United States)

1970-05-15

Based on the premise that there will always be a finite chance of a Plowshare project failure, the implications of such a failure are examined. It is suggested that the optimum reliability level will not necessarily be the highest attainable, but rather that which results in minimum average project cost. The type of performance guarantee that the U. S. should provide for nuclear explosive services, the determination of nuclear yield, courses of action to take in the event of failure, and methods to offset remedial costs are discussed. (author)

Reliability implications for commercial Plowshare applications

International Nuclear Information System (INIS)

Brumleve, T.D.

1970-01-01

Based on the premise that there will always be a finite chance of a Plowshare project failure, the implications of such a failure are examined. It is suggested that the optimum reliability level will not necessarily be the highest attainable, but rather that which results in minimum average project cost. The type of performance guarantee that the U. S. should provide for nuclear explosive services, the determination of nuclear yield, courses of action to take in the event of failure, and methods to offset remedial costs are discussed. (author)

Maintenance cost models in deregulated power systems under opportunity costs

International Nuclear Information System (INIS)

Al-Arfaj, K.; Dahal, K.; Azaiez, M.N.

2007-01-01

In a centralized power system, the operator is responsible for scheduling maintenance. There are different types of maintenance, including corrective maintenance; predictive maintenance; preventive maintenance; and reliability-centred maintenance. The main cause of power failures is poor maintenance. As such, maintenance costs play a significant role in deregulated power systems. They include direct costs associated with material and labor costs as well as indirect costs associated with spare parts inventory, shipment, test equipment, indirect labor, opportunity costs and cost of failure. In maintenance scheduling and planning, the cost function is the only component of the objective function. This paper presented the results of a study in which different components of maintenance costs were modeled. The maintenance models were formulated as an optimization problem with single and multiple objectives and a set of constraints. The maintenance costs models could be used to schedule the maintenance activities of power generators more accurately and to identify the best maintenance strategies over a period of time as they consider failure and opportunity costs in a deregulated environment. 32 refs., 4 tabs., 4 figs

Risk Management and Viability of Public Organizations. Development of a Risk Measurement Tool: The Case of Greece

Directory of Open Access Journals (Sweden)

Iordanis Eleftheriadis

2017-03-01

Full Text Available Purpose: This paper provides an important contribution towards the development of a valid, reliable and cost-effective instrument that reduces operational and economic risk levels in public sector organizations. Design/methodology/approach: A quantitative methodology based on the collection of primary data via a questionnaire has been adopted in this research. Findings: The research results showed that the measurement tool selected, applied, presented and proposed is comprised of three (3 scales. The reliability analysis proved that all three scales are reliable; therefore, they are suitable for use as a risk measurement instrument. Research limitations/implications: The study's academic contribution is the application and testing of the aforementioned measurement instruments, which can now be utilised by researchers in the field of risk management, to further advance the study of risk management in public organizations in Greece. On the empirical level, the implementation of these three measurement instruments can assist public organizations in Greece via an easy and fast assessment of economic and operational risks. Originality/value: This tool can help public organizations gain insight into the level of risk they face at any given point in time in order plan their actions accordingly. At the same time, central state administration will have the necessary tools to monitor and support the organizations it evaluates.

ORGANIZATION OF MANAGEMENT ACCOUNTING AND COST CALCULATION OF MINING IN JIU VALLEY

Directory of Open Access Journals (Sweden)

ILEANA-SORINA BOCA (RAKOS

2011-01-01

Full Text Available The scientific approach taken, due to the fact that a nationally more acute problem arises regarding mining restructuring, namely the closure of uneconomic mines, in this paper I want to report my finding on how management accounting is organized and which is the costing method currently applied by the seven mines in the Jiu Valley, which are currently functional, as well as to identify their limitations and advantages for improving them and identifying financial and economic solutions, demonstrating that in fact these are viable economic entities.

Well-founded cost estimation validated by experience

International Nuclear Information System (INIS)

LaGuardia, T.S.

2005-01-01

Full text: Reliable cost estimating is one of the most important elements of decommissioning planning. Alternative technologies may be evaluated and compared based on their efficiency and effectiveness, and measured against a baseline cost as to the feasibility and benefits derived from the technology. When the plan is complete, those cost considerations ensure that it is economically sound and practical for funding. Estimates of decommissioning costs have been performed and published by many organizations for many different applications. The results often vary because of differences in the work scope. Labor force cost, monetary considerations, oversight costs, the specific contaminated materials involved, the waste stream and peripheral costs associated with that type of waste, or applicable environmental compliance requirements. Many of these differences are unavoidable since a reasonable degree of reliability and accuracy can only be achieved by developing decommissioning cost estimates on a case-by-case site-specific basis. This paper describes the estimating methodology and process applied to develop decommissioning cost estimates. A major effort has been made to standardize these methodologies, and to understand the assumptions and bases that drive the costs. However, estimates are only as accurate as the information available from which to derive the costs. This information includes the assumptions of scope of the work, labour cost inputs, inflationary effects, and financial analyses that project these costs to year of expenditure. Attempts at comparison of estimates for two facilities of similar design and size must clearly identify the assumptions used in developing the estimate, and comparison of actual costs versus estimated costs must reflect these same assumptions. For the nuclear industry to grow, decommissioning estimating tools must improve to keep pace with changing technology, regulations and stakeholder issues. The decommissioning industry needs

Reliability demonstration test planning: A three dimensional consideration

International Nuclear Information System (INIS)

Yadav, Om Prakash; Singh, Nanua; Goel, Parveen S.

2006-01-01

Increasing customer demand for reliability, fierce market competition on time-to-market and cost, and highly reliable products are making reliability testing more challenging task. This paper presents a systematic approach for identifying critical elements (subsystems and components) of the system and deciding the types of test to be performed to demonstrate reliability. It decomposes the system into three dimensions (i.e. physical, functional and time) and identifies critical elements in the design by allocating system level reliability to each candidate. The decomposition of system level reliability is achieved by using criticality index. The numerical value of criticality index for each candidate is derived based on the information available from failure mode and effects analysis (FMEA) document or warranty data from a prior system. It makes use of this information to develop reliability demonstration test plan for the identified (critical) failure mechanisms and physical elements. It also highlights the benefits of using prior information in order to locate critical spots in the design and in subsequent development of test plans. A case example is presented to demonstrate the proposed approach

Field Programmable Gate Array Reliability Analysis Guidelines for Launch Vehicle Reliability Block Diagrams

Science.gov (United States)

Al Hassan, Mohammad; Britton, Paul; Hatfield, Glen Spencer; Novack, Steven D.

2017-01-01

Field Programmable Gate Arrays (FPGAs) integrated circuits (IC) are one of the key electronic components in today's sophisticated launch and space vehicle complex avionic systems, largely due to their superb reprogrammable and reconfigurable capabilities combined with relatively low non-recurring engineering costs (NRE) and short design cycle. Consequently, FPGAs are prevalent ICs in communication protocols and control signal commands. This paper will identify reliability concerns and high level guidelines to estimate FPGA total failure rates in a launch vehicle application. The paper will discuss hardware, hardware description language, and radiation induced failures. The hardware contribution of the approach accounts for physical failures of the IC. The hardware description language portion will discuss the high level FPGA programming languages and software/code reliability growth. The radiation portion will discuss FPGA susceptibility to space environment radiation.

Re-assessing reliability based on survived loads

NARCIS (Netherlands)

Schweckendiek, T.

2011-01-01

The reliability of flood defenses is often dictated by large uncertainties in the hydraulic loading and the structural resistance. Additional information decreases uncertainty, however, acquiring it is often costly. One source of information, even though in many cases readily available, is hardly

Reliability Improved Design for a Safety System Channel

Energy Technology Data Exchange (ETDEWEB)

Oh, Eung Se; Kim, Yun Goo [KHNP, Daejeon (Korea, Republic of)

2016-05-15

Nowadays, these systems are implemented with a same platform type, such as a qualified programmable logic controller (PLC). The platform intensively uses digital communication with fiber-optic links to reduce cabling costs and to achieve effective signal isolation. These communication interface and redundancies within a channel increase the complexness of an overall system design. This paper proposes a simpler channel architecture design to reduce the complexity and to enhance overall channel reliability. Simplified safety channel configuration is proposed and the failure probabilities are compared with baseline safety channel configuration using an estimated generic value. The simplified channel configuration achieves 40 percent failure reduction compare to baseline safety channel configuration. If this configuration can be implemented within a processor module, overall safety channel reliability is increase and costs of fabrication and maintenance will be greatly reduced.

Reliability Improved Design for a Safety System Channel

International Nuclear Information System (INIS)

Oh, Eung Se; Kim, Yun Goo

2016-01-01

Nowadays, these systems are implemented with a same platform type, such as a qualified programmable logic controller (PLC). The platform intensively uses digital communication with fiber-optic links to reduce cabling costs and to achieve effective signal isolation. These communication interface and redundancies within a channel increase the complexness of an overall system design. This paper proposes a simpler channel architecture design to reduce the complexity and to enhance overall channel reliability. Simplified safety channel configuration is proposed and the failure probabilities are compared with baseline safety channel configuration using an estimated generic value. The simplified channel configuration achieves 40 percent failure reduction compare to baseline safety channel configuration. If this configuration can be implemented within a processor module, overall safety channel reliability is increase and costs of fabrication and maintenance will be greatly reduced

29 CFR 95.27 - Allowable costs.

Science.gov (United States)

2010-07-01

... cost principles applicable to the entity incurring the costs. Thus, allowability of costs incurred by... Governments.” The allowability of costs incurred by non-profit organizations is determined in accordance with... Organizations.” The allowability of costs incurred by institutions of higher education is determined in...

Developing Reliable Life Support for Mars

Science.gov (United States)

Jones, Harry W.

2017-01-01

A human mission to Mars will require highly reliable life support systems. Mars life support systems may recycle water and oxygen using systems similar to those on the International Space Station (ISS). However, achieving sufficient reliability is less difficult for ISS than it will be for Mars. If an ISS system has a serious failure, it is possible to provide spare parts, or directly supply water or oxygen, or if necessary bring the crew back to Earth. Life support for Mars must be designed, tested, and improved as needed to achieve high demonstrated reliability. A quantitative reliability goal should be established and used to guide development t. The designers should select reliable components and minimize interface and integration problems. In theory a system can achieve the component-limited reliability, but testing often reveal unexpected failures due to design mistakes or flawed components. Testing should extend long enough to detect any unexpected failure modes and to verify the expected reliability. Iterated redesign and retest may be required to achieve the reliability goal. If the reliability is less than required, it may be improved by providing spare components or redundant systems. The number of spares required to achieve a given reliability goal depends on the component failure rate. If the failure rate is under estimated, the number of spares will be insufficient and the system may fail. If the design is likely to have undiscovered design or component problems, it is advisable to use dissimilar redundancy, even though this multiplies the design and development cost. In the ideal case, a human tended closed system operational test should be conducted to gain confidence in operations, maintenance, and repair. The difficulty in achieving high reliability in unproven complex systems may require the use of simpler, more mature, intrinsically higher reliability systems. The limitations of budget, schedule, and technology may suggest accepting lower and

Generating project value through design for reliability: on the development and implementation of a potential value framework

OpenAIRE

Woods, K. B. W.

2007-01-01

The current trend to economically exploit deepwater hydrocarbon reserves is to reduce the capital expenditure; accomplished by deploying subsea equipment. The financial benefit afforded is offset by the risk of high operational costs associated with failure. Recognition of the life cycle cost implications of subsea reliability have led to the development of the reliability strategy. This strategy adopts a risk based approach to design for reliability where only analyses (and th...

Reliability of the emergency ac-power system at nuclear power plants

International Nuclear Information System (INIS)

Battle, R.E.; Campbell, D.J.; Baranowsky, P.W.

1982-01-01

The reliability of the emergency ac-power systems typical of several nuclear power plants was estimated, the costs of several possible improvements was estimated. Fault trees were constructed based on a detailed design review of the emergency ac-power systems of 18 nuclear plants. The failure probabilities used in the fault trees were calculated from extensive historical data collected from Licensee Event Reports (LERs) and from operating experience information obtained from nuclear plant licensees. It was found that there are not one or two improvements that can be made at all plants to significantly increase the industry-average emergency ac-power-system reliability, but the improvements are varied and plant-specific. Estimates of the improvements in reliability and the associated cost are estimated using plant-specific designs and failure probabilities

Designing Cost-Competitive Technology Products through Cost Management

NARCIS (Netherlands)

Davila, T.; Wouters, Marc

2004-01-01

SYNOPSIS: As manufacturing innovations spread throughout leading organizations, product development becomes a more important source of competitive advantage. Within product development, cost management receives increasing attention. To date, cost management in new product development focuses

Human factors reliability Benchmark exercise

International Nuclear Information System (INIS)

Poucet, A.

1989-06-01

The Joint Research Centre of the European Commission has organized a Human Factors Reliability Benchmark Exercise (HF-RBE) with the aim of assessing the state of the art in human reliability modelling and assessment. Fifteen teams from eleven countries, representing industry, utilities, licensing organisations and research institutes, participated in the HF-RBE. The HF-RBE was organized around two study cases: (1) analysis of routine functional Test and Maintenance (T and M) procedures: with the aim of assessing the probability of test induced failures, the probability of failures to remain unrevealed and the potential to initiate transients because of errors performed in the test; (2) analysis of human actions during an operational transient: with the aim of assessing the probability that the operators will correctly diagnose the malfunctions and take proper corrective action. This report contains the final summary reports produced by the participants in the exercise

78 FR 45447 - Revisions to Modeling, Data, and Analysis Reliability Standard

Science.gov (United States)

2013-07-29

...; Order No. 782] Revisions to Modeling, Data, and Analysis Reliability Standard AGENCY: Federal Energy... Analysis (MOD) Reliability Standard MOD- 028-2, submitted to the Commission for approval by the North... Organization. The Commission finds that the proposed Reliability Standard represents an improvement over the...

Electricity supply. Older plants' impact on reliability and air quality

International Nuclear Information System (INIS)

England-Joseph, Judy A.; Adams, Charles M.; Wood, David G.; Feehan, Daniel J.; Veal, Howard F.; Skeen, John H. III; Koenigs, Melvin J.; Lichtenfeld, David I.; Seretakis, Pauline J.

1990-09-01

Life extension of fossil fuel plants is a relatively recent phenomenon; thus, utilities have little experience to demonstrate the longer-term operating reliability of plants with an extended service life. While utility industry officials and government and industry studies express optimism that these plants will continue to operate reliably, the officials and the studies also caution that it is too soon to determine how pursuing life extension will affect the reliability of the nation's electricity supply. According to DOE, the number of fossil fuel generating units' 30 years old or older is expected to increase from about 2,500 in 1989 to roughly 3,700 in 1998, increasing such plants' share of overall generating capacity from 13 percent in 1989 to 27 percent in 1998. EPA estimates that with existing air quality requirements, fossil fuel plant emissions will increase steadily during the coming decade. Proposed acid rain control legislation, which would affect many plants that may have their service life extended, would require utilities to significantly reduce emissions by the year 2000 but would allow utilities flexibility in deciding how and where to achieve the reductions. If such legislation is enacted, utilities generally are expected to find reducing emissions from existing plants more cost-effective than replacing them and to continue extending plants' service life. Officials of DOE and utility organizations expressed concern, however, that EPA could decide, as it did for one plant in 1988, that alterations made in extending the service life of plants exempted from the Clean Air Act would result in increased emissions and thus cause the altered plants to lose their exemption. According to the officials, the additional costs of achieving the Clean Air Act's standards could discourage some life extension projects. However, such decisions by EPA could also reduce the nation's total power plant emissions by eliminating an existing incentive to retain exempt

The Health Costs and Diseases in Medical Services Insurance Organization, Tehran Province, 1386 (2008

Directory of Open Access Journals (Sweden)

Ali Shojaei

2012-01-01

Full Text Available Objectives: The current research in addition to study of the diseases in the elders, surveys the health costs of these diseases. Methods & Materials: Study of the cost information and related diseases in (MSIO- Medical Services Insurance Organization, Tehran province, surveys costs and Medical Services of this group on 183093 hospitalized files. Results: 31% of hospital`s referrals and 37% of inpatient costs related to elders and display the expensive Services of this group of the Insured. The mean costs of every hospitalization in elderly groups were 4634384 rials, which was more than total mean costs, from all groups. Diagnostic code I27 (other cardio-vascular diseases, I20 (Angina pectoris, H25 (cataract, I25 (chronic IHD, I50 (heart failure, devote first to fifth grade of the prevalent Diagnosis cods (ICD in the aged group older than 60 and displays the most prevalence of the cardio-vascular system diseases in the elders. The most common surgical Code (California code in elderly (above 60 yrs. was related to Coronary Angioplasty, with its mean cost of 9116371 rials. And then was Cataract. 15% of the Global files are related to the elders which is equal to 23% of the charges of these files in this group of the elders. Extraction of Lens (Intra-capsular and extra-capsular Lens Insertion (57 code One-lateral Inguinal Hernia with or without excision of Hydrocele or Spermatocele except Incarcerated Inguinal Hernia (Global code 28, cholecystectomy with or without cholangiography or exploration of Biliary ducts (Global code 27 from first to third grade of the prevalent Global surgeries of the elders. Statistical test displays the Pierson coherent between the age and residence period and paid costs, There is a little positive coherent between the age and residence period in hospital and paid costs. Conclusion: These reviews show the results of the current study (the prevalent in-patient causes are adapted to the performed studies in this field and

Trade Off Relevance Dan Reliability: Isu Ifrs

OpenAIRE

Mahmudah, Hadi

2013-01-01

Financial reports containing qualitative characteristic that are useful for usernya.For a long time believed to be the existence of trade off between characteristic of qualitative relevance and reliability. Trade off due to the fact that the use of the method of measurement historical cost and fair value. Trade off occur because of the interests of for the purpose of the preparation of reports on finance. Accountability for the purpose of the measurement of the cost of historical still reliab...

Reliability of candida skin test in the evaluation of T-cell function in ...

African Journals Online (AJOL)

Ehab

2017-01-23

Jan 23, 2017 ... considered generally reliable under the age of 1 year.6 ... We sought to investigate the reliability of manually ... Conclusion: Candida intradermal test is a cost- effective ..... Ballow M. Historical perspectives in the diagnosis.

Reliability criteria selection for integrated resource planning

International Nuclear Information System (INIS)

Ruiu, D.; Ye, C.; Billinton, R.; Lakhanpal, D.

1993-01-01

A study was conducted on the selection of a generating system reliability criterion that ensures a reasonable continuity of supply while minimizing the total costs to utility customers. The study was conducted using the Institute for Electronic and Electrical Engineers (IEEE) reliability test system as the study system. The study inputs and results for conditions and load forecast data, new supply resources data, demand-side management resource data, resource planning criterion, criterion value selection, supply side development, integrated resource development, and best criterion values, are tabulated and discussed. Preliminary conclusions are drawn as follows. In the case of integrated resource planning, the selection of the best value for a given type of reliability criterion can be done using methods similar to those used for supply side planning. The reliability criteria values previously used for supply side planning may not be economically justified when integrated resource planning is used. Utilities may have to revise and adopt new, and perhaps lower supply reliability criteria for integrated resource planning. More complex reliability criteria, such as energy related indices, which take into account the magnitude, frequency and duration of the expected interruptions are better adapted than the simpler capacity-based reliability criteria such as loss of load expectation. 7 refs., 5 figs., 10 tabs

Out Brief for the Structural Reliability Partnership Workshop

Energy Technology Data Exchange (ETDEWEB)

Boyce, Brad [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Fang, Eliot [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kolski, Alyssa [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Zimmerman, Jonathan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Furmanski, Jevan [Exxon Mobil, Annandale, NJ (United States); Ravi-Chandar, Krishnaswamy [Univ. of Texas, Austin, TX (United States)

2017-08-30

The Structural Reliability Partnership Workshop was held in Albuquerque, NM on August 29-30, 2017 and was hosted by Sandia National Laboratories. Attendees were present from academia, industry and several other national laboratories. The workshop kicked off with an introduction to the SRP to familiarize potential members with what the purpose, structure and benefits would be to their organization. Technical overviews were given on several topics by attendees from each sector – national labs, universities and industry – to provide a snapshot of the type of work that is currently being conducted on structural reliability. Attendees were then given the opportunity to suggest and discuss potential Challenge Scenario topics. Three were ultimately decided upon as being the most important: Additive Manufacturing, Hydrogen Pipeline Steels, and Bolted Joined Structures. These were then analyzed using Quad Charts to determine What, How, Who, and Why these areas would be further investigated. Rather than restricting future research to only one area, the option was left open to investigate both the top two, depending on interest and cost associated with hosting such an event. More informal collaboration may be undertaken for the third topic if members have time and interest. Other items discussed pertained to the organization, structure and policies of the Partnership. Topics including Data Management, IP, and mechanisms of partnering/information sharing were touched upon but final decisions were not made. Further action is needed before this can be done. Action items were outlined and assigned, where possible. The next workshop is to be held in early August 2018 in Boulder, CO and is to be hosted by NIST. In the interim, quarterly updates are to take place via WebEx to maintain a line of communication and to ensure progress on both the administrative and technical tasks.

Cost Sharing in the Prevention of Supply Chain Disruption

Directory of Open Access Journals (Sweden)

Wen Wang

2017-01-01

Full Text Available We examine the influence of cost-sharing mechanism on the disruption prevention investment in a supply chain with unreliable suppliers. When a supply chain faces considerable loss following a disruption, supply chain members are motivated toward investing in manners that reduce their disruption probability. In improving supply chain reliability, the cost-sharing mechanism must be set appropriately to realize the efficiency of the disruption prevention investment. In a supply chain where the focal manufacturing company has its own subsidiary supplier and an outsourcing supplier, we analyze different forms of cost-sharing mechanisms when both suppliers confront disruption risks. Through the cost-sharing mechanisms presented in this study, supply chain members can improve their reliability via disruption prevention investments without considerably increasing the total supply chain cost. We present two concepts, the cost-sharing structure and the cost-sharing ratio, in this study. As the two key components of cost-sharing mechanism, these two elements constitute a practicable cost allocation mechanism to facilitate disruption prevention.

Reliability modeling and analysis for a novel design of modular converter system of wind turbines

International Nuclear Information System (INIS)

Zhang, Cai Wen; Zhang, Tieling; Chen, Nan; Jin, Tongdan

2013-01-01

Converters play a vital role in wind turbines. The concept of modularity is gaining in popularity in converter design for modern wind turbines in order to achieve high reliability as well as cost-effectiveness. In this study, we are concerned with a novel topology of modular converter invented by Hjort, Modular converter system with interchangeable converter modules. World Intellectual Property Organization, Pub. No. WO29027520 A2; 5 March 2009, in this architecture, the converter comprises a number of identical and interchangeable basic modules. Each module can operate in either AC/DC or DC/AC mode, depending on whether it functions on the generator or the grid side. Moreover, each module can be reconfigured from one side to the other, depending on the system’s operational requirements. This is a shining example of full-modular design. This paper aims to model and analyze the reliability of such a modular converter. A Markov modeling approach is applied to the system reliability analysis. In particular, six feasible converter system models based on Hjort’s architecture are investigated. Through numerical analyses and comparison, we provide insights and guidance for converter designers in their decision-making.

Reliable, Low Cost Distributed Generator/Utility System Interconnect: 2001 Annual Report

Energy Technology Data Exchange (ETDEWEB)

2003-08-01

This report details a research program to develop requirements that support the definition, design, and demonstration of a distributed generation-electric power system interconnection interface concept that allows distributed generation to be interconnected to the electric power system in a manner that provides value to end users without compromising reliability and performance.

Exploitation examination of reliability of coal dust systems

International Nuclear Information System (INIS)

Dojchinovski, Ilija; Trajkovski, Kole

1997-01-01

Designers and operators wish is, long, failure free operation at designed parameters of every system. Always we know the system start up time, but we don't know how long this system will operate successfully. Because of that in this article is given a method how, step by step, to determine the reliability of the system. Reliability parameters are obtained from experimental and operational data. When reliability parameters are determined then it is very easy to compare reliability of similar systems, for example excavators, or different systems, such as truck and rubber band transport system. Practical use of the theory of reliability is by purchasing of the systems when manufacturers have to have and present reliability parameters and on this way we can decide which system satisfies our needs regarding the quality-price-reliability. Reliability can be practically used in system operation where: 1) system reliability is maintained with proper start, use and shutdown of the system; 2) a system reliability is maintained with good maintenance organization; 3) a system reliability is maintained with innovations and improvements with final purpose removing of the imperfections experienced through the operation. Reliability is very important parameter in power generation plants. (Author)

A physical review on power system reliability factors

International Nuclear Information System (INIS)

Navid, Taghizadegan; Ahmad Reza, Zentabchi; Mohammad Ali, Tavakoli; Nader, Samsunchi; Mohammad Ali, Tavakoli

2005-01-01

Full text : Planning and design engineers and management must necessarily take into consideration the funds available, the requirements of regulatory agencies and other restrictions that may be imposed, as well as availability of equipment and supplies. A well-designed electrical power system strikes a reasonable between reliability and cost. A prime responsibility of power system operators is to operate their systems in such a way that will provide the maximum reliability of service possible with the facilities under their control

7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

Science.gov (United States)

2010-01-01

... must include comprehensive economic present-value analyses of the costs and revenues of the available... assessments of service reliability and financing requirements and risks. Requirements for analyzing purchased... costs; (2) Financing requirements and risks; (3) System reliability; (4) Alternative unit sizes; (5...

Waste package reliability analysis

International Nuclear Information System (INIS)

Pescatore, C.; Sastre, C.

1983-01-01

Proof of future performance of a complex system such as a high-level nuclear waste package over a period of hundreds to thousands of years cannot be had in the ordinary sense of the word. The general method of probabilistic reliability analysis could provide an acceptable framework to identify, organize, and convey the information necessary to satisfy the criterion of reasonable assurance of waste package performance according to the regulatory requirements set forth in 10 CFR 60. General principles which may be used to evaluate the qualitative and quantitative reliability of a waste package design are indicated and illustrated with a sample calculation of a repository concept in basalt. 8 references, 1 table

Activity-based Costing (ABC) and Activity-based Management(ABM)Implementation – Is This the Solution for Organizations to Gain Profitability?

OpenAIRE

Ildikó Réka CARDOS; Stefan PETE

2011-01-01

Adherents of ABC/ABM systems claimed traditional management accounting systems generated misleading costs in a contemporary, tumultuous, often changing business environment and implementing ABC/ABM would remedy this. That is why activity-based costing (ABC) and activity-based management (ABM) represents the symbol of improved competitiveness and efficiency in every organization.The purpose of this article – after analyzing the existing literature in the field – is to emphasize that new cost s...

Bayesian reliability demonstration for failure-free periods

Energy Technology Data Exchange (ETDEWEB)

Coolen, F.P.A. [Department of Mathematical Sciences, Science Laboratories, University of Durham, South Road, Durham, DH1 3LE (United Kingdom)]. E-mail: frank.coolen@durham.ac.uk; Coolen-Schrijner, P. [Department of Mathematical Sciences, Science Laboratories, University of Durham, South Road, Durham, DH1 3LE (United Kingdom); Rahrouh, M. [Department of Mathematical Sciences, Science Laboratories, University of Durham, South Road, Durham, DH1 3LE (United Kingdom)

2005-04-01

We study sample sizes for testing as required for Bayesian reliability demonstration in terms of failure-free periods after testing, under the assumption that tests lead to zero failures. For the process after testing, we consider both deterministic and random numbers of tasks, including tasks arriving as Poisson processes. It turns out that the deterministic case is worst in the sense that it requires most tasks to be tested. We consider such reliability demonstration for a single type of task, as well as for multiple types of tasks to be performed by one system. We also consider the situation, where tests of different types of tasks may have different costs, aiming at minimal expected total costs, assuming that failure in the process would be catastrophic, in the sense that the process would be discontinued. Generally, these inferences are very sensitive to the choice of prior distribution, so one must be very careful with interpretation of non-informativeness of priors.

Bayesian reliability demonstration for failure-free periods

International Nuclear Information System (INIS)

Coolen, F.P.A.; Coolen-Schrijner, P.; Rahrouh, M.

2005-01-01

We study sample sizes for testing as required for Bayesian reliability demonstration in terms of failure-free periods after testing, under the assumption that tests lead to zero failures. For the process after testing, we consider both deterministic and random numbers of tasks, including tasks arriving as Poisson processes. It turns out that the deterministic case is worst in the sense that it requires most tasks to be tested. We consider such reliability demonstration for a single type of task, as well as for multiple types of tasks to be performed by one system. We also consider the situation, where tests of different types of tasks may have different costs, aiming at minimal expected total costs, assuming that failure in the process would be catastrophic, in the sense that the process would be discontinued. Generally, these inferences are very sensitive to the choice of prior distribution, so one must be very careful with interpretation of non-informativeness of priors

Analysis of the Possibility to Organize the Management Accounting through the Target Costing (TC Method in the Romanian Entities

Directory of Open Access Journals (Sweden)

Sorinel CĂPUŞNEANU

2011-09-01

Full Text Available This article presents a way of organizing the management accounting and cost calculation through the Target Costing method. There are treated the development stages of Target Costing method, and the role of the management accountant in the development and implementation of this method. The causes behind the choice to adapt the principles of Target Costing method to the Romanian General Accounting Plan and the operation of accounts used in highlighting economic and financial operations at the entity leve have been analyzedl. There are treated theoretical and applied the methodological steps taken in the management accounting and cost calculation. The article ends with the conclusions of the authors about the possibility of adapting the principles of Target Costing method to the Romanian General Accounting Plan and the advantages offered by this method.

What Are the Real Procedural Costs of Bariatric Surgery? A Systematic Literature Review of Published Cost Analyses.

Science.gov (United States)

Doble, Brett; Wordsworth, Sarah; Rogers, Chris A; Welbourn, Richard; Byrne, James; Blazeby, Jane M

2017-08-01

This review aims to evaluate the current literature on the procedural costs of bariatric surgery for the treatment of severe obesity. Using a published framework for the conduct of micro-costing studies for surgical interventions, existing cost estimates from the literature are assessed for their accuracy, reliability and comprehensiveness based on their consideration of seven 'important' cost components. MEDLINE, PubMed, key journals and reference lists of included studies were searched up to January 2017. Eligible studies had to report per-case, total procedural costs for any type of bariatric surgery broken down into two or more individual cost components. A total of 998 citations were screened, of which 13 studies were included for analysis. Included studies were mainly conducted from a US hospital perspective, assessed either gastric bypass or adjustable gastric banding procedures and considered a range of different cost components. The mean total procedural costs for all included studies was US$14,389 (range, US$7423 to US$33,541). No study considered all of the recommended 'important' cost components and estimation methods were poorly reported. The accuracy, reliability and comprehensiveness of the existing cost estimates are, therefore, questionable. There is a need for a comparative cost analysis of the different approaches to bariatric surgery, with the most appropriate costing approach identified to be micro-costing methods. Such an analysis will not only be useful in estimating the relative cost-effectiveness of different surgeries but will also ensure appropriate reimbursement and budgeting by healthcare payers to ensure barriers to access this effective treatment by severely obese patients are minimised.

45 CFR 602.22 - Allowable costs.

Science.gov (United States)

2010-10-01

... CFR part 31. Contract Cost Principles and Procedures, or uniform cost accounting standards that comply.... (b) Applicable cost principles. For each kind of organization, there is a set of Federal principles... principles applicable to the organization incurring the costs. The following chart lists the kinds of...

Wind turbine reliability : a database and analysis approach.

Energy Technology Data Exchange (ETDEWEB)

Linsday, James (ARES Corporation); Briand, Daniel; Hill, Roger Ray; Stinebaugh, Jennifer A.; Benjamin, Allan S. (ARES Corporation)

2008-02-01

The US wind Industry has experienced remarkable growth since the turn of the century. At the same time, the physical size and electrical generation capabilities of wind turbines has also experienced remarkable growth. As the market continues to expand, and as wind generation continues to gain a significant share of the generation portfolio, the reliability of wind turbine technology becomes increasingly important. This report addresses how operations and maintenance costs are related to unreliability - that is the failures experienced by systems and components. Reliability tools are demonstrated, data needed to understand and catalog failure events is described, and practical wind turbine reliability models are illustrated, including preliminary results. This report also presents a continuing process of how to proceed with controlling industry requirements, needs, and expectations related to Reliability, Availability, Maintainability, and Safety. A simply stated goal of this process is to better understand and to improve the operable reliability of wind turbine installations.

Reliability and Maintainability Engineering - A Major Driver for Safety and Affordability

Science.gov (United States)

Safie, Fayssal M.

2011-01-01

The United States National Aeronautics and Space Administration (NASA) is in the midst of an effort to design and build a safe and affordable heavy lift vehicle to go to the moon and beyond. To achieve that, NASA is seeking more innovative and efficient approaches to reduce cost while maintaining an acceptable level of safety and mission success. One area that has the potential to contribute significantly to achieving NASA safety and affordability goals is Reliability and Maintainability (R&M) engineering. Inadequate reliability or failure of critical safety items may directly jeopardize the safety of the user(s) and result in a loss of life. Inadequate reliability of equipment may directly jeopardize mission success. Systems designed to be more reliable (fewer failures) and maintainable (fewer resources needed) can lower the total life cycle cost. The Department of Defense (DOD) and industry experience has shown that optimized and adequate levels of R&M are critical for achieving a high level of safety and mission success, and low sustainment cost. Also, lessons learned from the Space Shuttle program clearly demonstrated the importance of R&M engineering in designing and operating safe and affordable launch systems. The Challenger and Columbia accidents are examples of the severe impact of design unreliability and process induced failures on system safety and mission success. These accidents demonstrated the criticality of reliability engineering in understanding component failure mechanisms and integrated system failures across the system elements interfaces. Experience from the shuttle program also shows that insufficient Reliability, Maintainability, and Supportability (RMS) engineering analyses upfront in the design phase can significantly increase the sustainment cost and, thereby, the total life cycle cost. Emphasis on RMS during the design phase is critical for identifying the design features and characteristics needed for time efficient processing

Development of the Centralized Reliability Data Organization (CREDO)

International Nuclear Information System (INIS)

Haas, P.M.; Bott, T.F.; Knee, H.E.; Manning, J.J.; Hudson, S.D.; Greene, N.M.; Woodside, M.A.

1979-01-01

CREDO has been established to meet the needs of the US Breeder Reactor Program and the advanced reactor community for a centralized source of accurate reliability/maintainability data and data-related services. The center provides for a comprehensive program of collection, evaluation, and dissemination of data and for necessary user services. A steering committee of nationally recognized experts has been formed to guide CREDO development and operation. Historic data have been collected, analyzed, and published. Routine, continuous data collection and processing has been initiated at US sites. Interfaces with existing data bases have been established. Special user services are under development

COST BM0607

International Nuclear Information System (INIS)

Jong, M. de

2009-01-01

COST is an intergovernmental framework for European Cooperation in Science and Technology, allowing the coordination of nationally-funded research on a European level. COST contributes to reducing the fragmentation in European research investments and opening the European Research Area to cooperation worldwide. COST is specifically designed to network researchers mainly within the European Union that work on a specific topic. This COST BM0607 Action on cancer therapy using innovative targeting nanomedicines is highly multidisciplinary: nuclear medicine physicians, clinical oncologists, surgeons, physicists, radiobiologists, (in)organic chemists, radiochemists, radiopharmacists, pathologists and scientists from biomics participate in it. They define innovative new targets for cancer therapy, develop lead compounds and new radiolabelled ligands as vectors, perform molecular imaging and biologic testing, develop improved software and protocols for dosimetric calculations and select new vectors for early human use. Within the COST BM0607 more than 100 scientists from 21 countries are participating to work within 5 different working groups. Working group 1 works on the establishment of Database on Molecular Targets for Targeted Radionuclide Therapy, working group 2 deals with the development and improvement of chemistry related to new molecules for targeted radionuclide therapy. Working group 3 is dedicated to dosimetry aspects, whereas working group 4 tries to optimize the use of new radionuclides for therapy from cyclotron, reactor and generator production. Finally, working group 5 has the aim to bring together research related to pharmacology and small animal imaging with new tracers for targeted radionuclide therapy. COST thereby organizes annual meetings of the whole group and in between dedicated meetings of the working groups. Besides organizing meetings one aim of COST is additionally to promote young researchers where short term scientific missions (STSM) are

Reliability centred maintenance of nuclear power plant facilities

International Nuclear Information System (INIS)

Kovacs, Zoltan; Novakova, Helena; Hlavac, Pavol; Janicek, Frantisek

2011-01-01

A method for the optimization of preventive maintenance nuclear power plant equipment, i.e. reliability centred maintenance, is described. The method enables procedures and procedure schedules to be defined such as allow the maintenance cost to be minimized without compromising operational safety or reliability. Also, combinations of facilities which remain available and ensure reliable operation of the reactor unit during the maintenance of other pieces of equipment are identified. The condition-based maintenance concept is used in this process, thereby preventing unnecessary operator interventions into the equipment, which are often associated with human errors. Where probabilistic safety assessment is available, the most important structures, systems and components with the highest maintenance priority can be identified. (orig.)

Reliability demonstration of imaging surveillance systems

International Nuclear Information System (INIS)

Sheridan, T.F.; Henderson, J.T.; MacDiarmid, P.R.

1979-01-01

Security surveillance systems which employ closed circuit television are being deployed with increasing frequency for the protection of property and other valuable assets. A need exists to demonstrate the reliability of such systems before their installation to assure that the deployed systems will operate when needed with only the scheduled amount of maintenance and support costs. An approach to the reliability demonstration of imaging surveillance systems which employ closed circuit television is described. Failure definitions based on industry television standards and imaging alarm assessment criteria for surveillance systems are discussed. Test methods which allow 24 hour a day operation without the need for numerous test scenarios, test personnel and elaborate test facilities are presented. Existing reliability demonstration standards are shown to apply which obviate the need for elaborate statistical tests. The demonstration methods employed are shown to have applications in other types of imaging surveillance systems besides closed circuit television

Reliability Assessment of Solder Joints in Power Electronic Modules by Crack Damage Model for Wind Turbine Applications

DEFF Research Database (Denmark)

Kostandyan, Erik; Sørensen, John Dalsgaard