Reliability Of Evaluation Results Research Articles

RECENT STUDY ON THE RELATED PROBLEMS IN EVALUATION OF MECHANICAL PROPERTIES FOR MEMS MATERIALS

In order to obtain reliable evaluation result by nanoindentation, the related problems during measurement of the hardness and elastic modulus are investigated. Two quantitative approaches, i.e. calculating actual contact area and correcting contact depth errors, are proposed to deal with the significant pile-up errors for indentation on those ductile soft materials, especially thin soft metal films on hard substrates. The various influence factors during indentation are analyzed, and a new method for uncertainty estimation in hardness and elastic modulus is provided based on the random-fuzzy variables. Through the illustration of Au/glass-ceramic and Al/7059 glass, both the quantitative approaches are suitable for the elastically matching film-substrate systems. The measurement uncertainties in hardness and elastic modulus of Si(100) are effectively estimated, and all possible influencing effects on uncertainty can be involved.

Potential Freeway Congestion Severity Measure: Impact of Continuous Congestion Patterns

To better understand the characteristics of traffic congestion and efficiently employ congestion measures for interstate highway systems, this study examined the limitations of the congestion measures currently in use such as the percent of congestion and the duration of continuous congestion. Based on this study, these congestion measures provided different results of the congestion severity for even the same interstate highway segment, which means that the use of a single measure might not give a reliable evaluation result. In order to minimize the potential bias and enhance the advantage of each congestion measure, this study proposed a composite congestion severity measure by combining congestion information of both percent of congestion and duration of continuous congestion measures. The writers found that the proposed composite congestion severity measure efficiently identified the levels of the congestion severity of interstate highway segments and that it could be instantly accomplished with the existing loop detector count systems in most states. This proposed measure may be a potential candidate for describing levels of congestion severity and can provide a proper guideline for transportation engineers or decision makers to efficiently allocate available budget and resources to correct applicable interstate segments.

Introduction of SCRI model for creep rupture life assessment

A “service condition-creep rupture property” interference model (SCRI model for short) based on Z parameter method is proposed to predict the reliability of creep rupture life for high temperature components. The dispersibility of creep rupture property and the fluctuation of service conditions such as servicing temperature and stress are considered in this model. The scattering of creep rupture data is generally supported by normal distribution. Monte-Carlo method is applied to evaluate the reliability at a certain operating condition by simulating the fluctuation of service temperature and stress. HK40 steel has been used as an example to demonstrate the influence of creep rupture property dispersibility and operating condition fluctuation on the result of reliability evaluation.

Machining localization and quality evaluation of parts with sculptured surfaces using SQP method

Using automatic localization to ensure sufficient machining allowance or derive reliable evaluation results of machining quality, it is possible to cope with the case where the coordinate system in a part design specification is different from that for machining or measuring the part. To achieve workpiece localization and machining quality evaluation, it is essential to find the optimum Euclidean transformation that aligns the nominal mode to the sample points from a workpiece. This paper describes a unified algorithm for workpiece localization and quality evaluation. The optimum alignment model is firstly established with minimax criteria, and then sequential quadratic programming (SQP) is proposed to solve the optimization problem. A computational algorithm of point-to-surface distance and a linear differential motion model of the objective function with respect to alignment parameters are subsequently provided. The results show that the SQP-based workpiece localization and quality evaluation method is computationally more efficient than those based on direct search algorithms. It is found that the proposed method is effective in machining localization and quality evaluation even with a large set of sample points.

공공 정보화사업에 대한 통합성과 평가모델 개발과 적용에 관한 연구

최근 정보화에 대한 성과평가는 투자성과에 미치는 효과를 정량적, 정성적으로 분석하여, 전통적인 투자 수익률에 근거한 가치평가방법의 한계를 극복하기 위한 다양한 성과평가방법이 응용되고 있다. 하지만 공공분야의 성과평가는 평가영역에 대한 정성적 평가 중심의 성과여부를 도출하는데 머무를 뿐, 정보화 품질을 향상시키는 데까지는 이르지 못하는 단점이 있다. 따라서 본 논문에서는 기존 공공분야 성과평가의 한계점을 개선하고 품질평가와 정량적 평가를 반영함으로써, 정보화 품질 향상과 평가결과의 객관성 및 신뢰성을 보장하는 통합성과평가모델을 제안한다. 그리고 정보화사업으로 추진된 행정정보DB구축사업을 대상으로 사업목적을 고려한 평가영역별 반영비율 및 가중치를 적용한 평가결과를 도출하였다. Recently, an evaluation for information system performance analysis an investment effect quantitatively and qualitatively. So various performance evaluation methods are applied to overcome a limitation which is based on traditional investment returns. However a performance evaluation in public service only derives that a result which is qualitatively evaluated about evaluation domain is yes or no, the performance evaluation does not improve in quality of information system. So in this paper we improve existing performance evaluation methods in public service and add a quality evaluation and quantitative evaluation in the methods. Therefore we propose an integrated evaluation model which guarantees objectivity and reliability of evaluation result and which improves an information system. We consider a project object of an Administration Information DB Construction Project which is promoted in information-oriented project and derive an evaluation result which is applied reflection ratio and weight in each evaluation domain to show a validity of the proposed model.

露天資源開発の現状と新たな展開を支える技術 露天採掘場の景観評価方法の信頼性の検討

Authors have studied the landscape evaluation of a quarry using videos or still pictures as change stimulus. As a result of these studies, it is found that a video is more suitable than a still picture as change stimulus for the reason why it has reality and liveliness. But more time, labors and costs are required for creations of change stimulus and experiments using a video rather than a still picture.This study aimed at establishment of the reasonable and reliable experimental method for landscape evaluations of quarry. Then, we carried out three investigations as follows;(1) The suitable presentation method of a change stimulus was examined. It became clear that the presentation by a screen projection with near an actual scale was suitable for videos, while the presentation by a personal computer monitor was suitable for still pictures. (2) The applicability of the animation for change stimulus created using the virtual reality system (VRS) was examined. It was judged that its application to the landscape evaluation of quarry is possible for the animation landscape simulation created with VRS.(3) The minimum number of the persons, from which the reliable and stable evaluation results is obtained, was examined. It became clear that the minimum number of the persons is about 30, even when a change stimulus is which of an animation and a still picture.

道路橋鋼製橋脚の荷重係数設計フォーマットの提案

After the Hanshin-Awaji (Kobe) Earthquake occurred on January 17, 1995, the earthquake design codes of highway bridges were revised by the Japanese Association of Road Engineering. However, the revised edition of codes were performed within the conventional design paradigm. They are not written based on the general principle of the reliability design of the structure (ISO2394) adopted in Europe and America. In this paper, a load factors design format based on the reliability theory for steel rigid-frame piers at elastic limit states is proposed using the reliability evaluation results of the author's early papers. The load factors are calculated so that the steel piers are ensured the target reliability index βT at the elastic limit state. The steel rigid-frame piers are redesign by using proposed design format and the reliability indices of these piers are calculated to check the effectiveness of the proposed format.

SUE inspection: an effective method for systematic usability evaluation of hypermedia

SUE inspection is a novel usability evaluation method for hypermedia, which falls into the category of inspection methods. Its primary goal is to favor a systematic usability evaluation (SUE), for supplying hypermedia usability inspectors with a structured flow of activities, allowing them to obtain more reliable, comparable, and cost-effective evaluation results. This is obtained especially due to the use of evaluation patterns, called abstract tasks (AT), which describe in details the activities that evaluators must carry out during inspection. AT helps share and transfer evaluation know-how among different evaluators, thus making it easier to learn the SUE inspection method by newcomers. A further notable advantage provided by the SUE inspection over other existent approaches is that it focuses on navigation and information structures, making evident some problems that other surface-oriented approaches might not reveal. This paper describes the SUE inspection for hypermedia. It also reports on a validation experiment, involving 28 evaluators, that has shown the major effectiveness and efficiency of the SUE inspection for hypermedia, with respect to traditional heuristic evaluation techniques.

Dynamic system reliability study modeling

This article extends conventional reliability modeling to a comprehensive modeling to cover system dynamic response and plant process response as the consequence of system component failures. The study results indicate the load outages from system dynamic response and process response cannot be neglected-they may have significant contributions to the system load outages. The example system study shows the conventional reliability modeling covers about 50% of total load outages. This modeling provides a more realistic approach. The modeling also considers the component failure rate adjustment for effects of component age and maintenance quality. The modelling, using accumulations of system segment contributions to load outages, is a practical approach for industrial systems. The results of reliability evaluation in terms of load outage indices, segment contributions, and overall system reliability indices, provide valuable information for plant management decision making with respect to return-of-investment in system reliability improvement projects. The reliability modeling can be coordinated with other system planning studies, such as system expansion and redesign, because these studies usually require system load flow, short circuit and transient stability analysis. These studies are usually involved in the evaluations of many alternatives. With the reliability evaluations added into the system planning study, the results will be more valuable for decision making among many alternatives.

Trade-Offs in Designing a Social Program Experiment

Recent policy actions have focused more attention on programs to reduce risks to teenagers. This type of policy scrutiny raises evaluation stakes. This paper addresses the challenges of evaluating teenage risk-reduction programs, particularly programs that operate in schools. I argue that the need for reliable evaluation results favors using random assignment, that randomly assigning schools is suitable for common types of risk-reduction programs, and that under reasonable conditions, an evaluation involving ten districts and eight schools in each district will be able to detect program impacts that fall within an expected range based on previous program evaluations. An evaluation will also need to consider (1) ways to get parental consent, (2) the effects of student mobility on the evaluation's power, and (3) ways to minimize attrition from follow-up survey samples.

Strength Design and Reliability Evaluation of a Hybrid Ceramic Stator Vane for Industrial Gas Turbines

Employing ceramic materials for the critical components of industrial gas turbines is anticipated to improve the thermal efficiency of power plants. We developed a first-stage stator vane for a 1300°C class, 20-MW industrial gas turbine. This stator vane has a hybrid ceramic/metal structure, to increase the strength reliability of brittle ceramic parts, and to reduce the amount of cooling air needed for metal parts as well. The strength design results of a ceramic main part are described. Strength reliability evaluation results are also provided based on a cascade test using combustion gas under actual gas turbine running conditions.

Modifications to the Bühler Laboratory Mill to Produce a Flour Comparable in Yield and Quality to the Allis-Chalmers Laboratory Mill

Modifications to the Bühler laboratory mill to reduce moisture loss during milling and to improve flour yield are described. Moisture loss is reduced by returning air to the mill from the duct on the outlet of the exhaust fan through baffled chambers into the back of the sifter sections. Holes cut in the top covering plates and fitted with 18XX Swiss bolting cloth release air pressure and balance air flow throughout the mill. Roll settings, clothing and flow are altered to achieve flour yields of about 75% for high quality Canadian hard red spring wheat with the aid of a laboratory bran finisher. The modified Bühler mill gave similar flour properties compared to the Allis-Chalmers laboratory mill and proved to give equally reliable wheat quality evaluation results.