• Title/Summary/Keyword: Performance testing

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Research for Ultrasonic Transducer Manufacturing and Evaluation Technique (초음파탐촉자(超音波探觸子) 제작(製作) 및 평가기술(評價技術)에 관한 연구(硏究))

  • Yoon, K.S.;Huh, H.;Park, D.Y.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.7 no.1
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    • pp.18-31
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    • 1987
  • For the purpose of domestic production of ultrasonic transducer, experiments on material selection for backing and matching layer, and electrical impedance matching between transducer and equipment were performed. The characteristics of manufactured transducers with experimental results were analyzed and compared with foreign products. Through the evaluation of the transducers manufactured and the comparision with foreign products, it is confirmed that the transducers manufactured show the good performance characteristics and efficiency.

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Development of Chollian Bipropellant Propulsion System (천리안위성 이원추진시스템 개발)

  • Han, Cho-Young;Lim, Cheol-Ho
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.19 no.1
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    • pp.94-100
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    • 2011
  • This paper gives a brief overview of the COMS CPS development process from start to finish. The manufacturing techniques used for CPS were founded on established generic processes that have been developed and proven on previous satellite programs, and have used the expertise and facilities in the framework of international collaboration. Manufacture and testing of the CPS were successfully accomplished, and COMS CPS demonstrated good performance in the launch phase.

Understanding of Nondestructive Testing Technique (비파괴검사기술의 이해)

  • Ho, Nam
    • Journal of the Korean Professional Engineers Association
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    • v.33 no.6
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    • pp.23-29
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    • 2000
  • The nondestructive tests(NDT) are widely applied at various industrial job sites to detect defects and flaws early and thus to diagnose the quality and integrity of components, structures and systems. This paper discusses the R&MD history of various nondestructive testing techniques, their applications and many technical as well as safety issues identified, particularly in the performance of radiography. Also discussed are the principles of inspection methods and NDT qualifications that should be applied at the industrial job sites. As a result, this paper provides suggestions for improvement in Government programs to promote th NDT industry, for more systematic operation through a direct with the owner, and also for improvement in working conditions for NDT workers.

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Discussion of Dynamic Fluid Pressures of a Submerged Deposit of Sand (수중 모래지반의 동수압 발현)

  • Kim, Ha-Young
    • Proceedings of the Korean Geotechical Society Conference
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    • 2006.03a
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    • pp.546-551
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    • 2006
  • This study is concerned with the dynamic behaviour of a fluid layer and a submerged deposit of sand in a rigid rectangular container when subjected to horizontal shaking. Detailed analyses are made of the interaction between the fluid pressure field and the excess pore pressure changes in the sand deposit, in terms of finite-element modelling as well as of two-layer fluid theory. It is shown that the predicted performance compares favourably with what has been observed in centrifugal shaking-table testing on submerged sand deposits.

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Testing the Goodness of Fit of a Parametric Model via Smoothing Parameter Estimate

  • Kim, Choongrak
    • Journal of the Korean Statistical Society
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    • v.30 no.4
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    • pp.645-660
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    • 2001
  • In this paper we propose a goodness-of-fit test statistic for testing the (null) parametric model versus the (alternative) nonparametric model. Most of existing nonparametric test statistics are based on the residuals which are obtained by regressing the data to a parametric model. Our test is based on the bootstrap estimator of the probability that the smoothing parameter estimator is infinite when fitting residuals to cubic smoothing spline. Power performance of this test is investigated and is compared with many other tests. Illustrative examples based on real data sets are given.

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Study of Testing Methods for Combustible Properties of Finishing Materials Applied into Nuclear Power Plants (원전구조물 적용 마감재의 국내 연소시험방법 조사연구)

  • Kwon, In-Kyu
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2018.05a
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    • pp.60-61
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    • 2018
  • Finishing materials are very important to restrain fire spread from a compartment to another in a fire situation. Therefore, the evaluation of combustible properties for the combustible material is essential to apply finishing materials into a generic buillding or s special occupancy structure. In this study, the testing methods for evaluation of combustible performance of finishing materials of domestic were surveyed in order to prepare the guideline of application of finishing materials in nulear power plant.

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A Report on Test Results of Pressure Operated Switch (압력스위치 성능시험보고)

  • Gwon, O-Seung
    • Fire Protection Technology
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    • s.12
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    • pp.5-9
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    • 1992
  • This reoprt is explained about test results of pressure operated switch for automatic fire extinguishing systems. It may include pressure operated Switch for automatic water supply control valves for use in automatic fire suppression system for fire protection service. The testing program was progressed devided by Two testing items, extermal oppearane test and performance test. The object of this report is present the problem which appear from the analysis of test results.

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Application of Bootstrap Method for Change Point Test based on Kernel Density Estimator

  • Kim, Dae-Hak
    • Journal of the Korean Data and Information Science Society
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    • v.15 no.1
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    • pp.107-117
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    • 2004
  • Change point testing problem is considered. Kernel density estimators are used for constructing proposed change point test statistics. The proposed method can be used to the hypothesis testing of not only parameter change but also distributional change. Bootstrap method is applied to get the sampling distribution of proposed test statistic. Small sample Monte Carlo Simulation were also conducted in order to show the performance of proposed method.

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User Centered Interface Design of Web-based Attention Testing Tools: Inhibition of Return(IOR) and Graphic UI (웹 기반 주의력 검사의 사용자 인터페이스 설계: 회귀억제 과제와 그래픽 UI를 중심으로)

  • Kwahk, Ji-Eun;Kwak, Ho-Wan
    • Korean Journal of Cognitive Science
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    • v.19 no.4
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    • pp.331-367
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    • 2008
  • This study aims to validate a web-based neuropsychological testing tool developed by Kwak(2007) and to suggest solutions to potential problems that can deteriorate its validity. When it targets a wider range of subjects, a web-based neuropsychological testing tool is challenged by high drop-out rates, lack of motivation, lack of interactivity with the experimenter, fear of computer, etc. As a possible solution to these threats, this study aims to redesign the user interface of a web-based attention testing tool through three phases of study. In Study 1, an extensive analysis of Kwak's(2007) attention testing tool was conducted to identify potential usability problems. The Heuristic Walkthrough(HW) method was used by three usability experts to review various design features. As a result, many problems were found throughout the tool. The findings concluded that the design of instructions, user information survey forms, task screen, results screen, etc. did not conform to the needs of users and their tasks. In Study 2, 11 guidelines for the design of web-based attention testing tools were established based on the findings from Study 1. The guidelines were used to optimize the design and organization of the tool so that it fits to the user and task needs. The resulting new design alternative was then implemented as a working prototype using the JAVA programming language. In Study 3, a comparative study was conducted to demonstrate the excellence of the new design of attention testing tool(named graphic style tool) over the existing design(named text style tool). A total of 60 subjects participated in user testing sessions where their error frequency, error patterns, and subjective satisfaction were measured through performance observation and questionnaires. Through the task performance measurement, a number of user errors in various types were observed in the existing text style tool. The questionnaire results were also in support of the new graphic style tool, users rated the new graphic style tool higher than the existing text style tool in terms of overall satisfaction, screen design, terms and system information, ease of learning, and system performance.

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The Design and Implementation of a Performance Evaluation Tool for the Face Recognition System (얼굴인식시스템 성능평가 도구의 설계 및 구현)

  • Shin, Woo-Chang
    • Journal of Information Technology Services
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    • v.6 no.2
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    • pp.161-175
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    • 2007
  • Face recognition technology has lately attracted considerable attention because of its non-intrusiveness, usability and applicability. Related companies insist that their commercial products show the recognition rates more than 95% according to their self-testing. But, the rates cannot be admitted as official recognition rates. So, performance evaluation methods and tools are necessary to objectively measure the accuracy and performance of face recognition systems. In this paper, I propose a reference model for biometrics recognition evaluation tools, and implement an evaluation tool for the face recognition system based on the proposed reference model.