• Title/Summary/Keyword: Test&Evaluation

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Performance Evaluation of Fin-Stabilizer by Model Test and Time-domain Simulation (시뮬레이션과 모형시험을 통한 핀 안정기의 성능평가)

  • 홍사영;김현조;최윤락;신영균;유병석;이승준
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2001.10a
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    • pp.86-90
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    • 2001
  • Demand of good seakeeping perfomace is increasing for sea going vessels such as cruisers, naval ships and container ships. Especillay roll motion is one of major concerns in evaluation of seakeeping performance due to its large resonace motion. Since large roll resonance motion is mainly arised from inherent small damping. use of additional mechnism to provide roll damping can significantly reduce roll motion. In this paper, a reliable performace evaluation method of fin stabilizer, which is very useful for stabilizing roll motion of mid and high speed vessls, is described. Model test and time domain simulation methods are adopted for performance evaluation in which real operating situation of fin stabilizer can be exactly modelled. Model test and simulation results show good correlations between model test and simulation results.

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Hydrodynamic Evaluation Method for Developing the Inflatable Kayak (인플래터블 카약 개발을 위한 유체역학적 성능평가 기법)

  • Ki, Jae-Seok;Hah, Chong-Ku;Jang, Ho-Yun
    • Journal of Advanced Marine Engineering and Technology
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    • v.36 no.5
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    • pp.627-634
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    • 2012
  • This study includes results of basin test for hydrodynamic performance evaluation with a developed inflatable kayak. Inclining experiment and turning trial experiment of the developed inflatable kayak and an abroad product were carried out in the Ocean engineering Basin. Resistance test was carried out by using downscale model in the circulating water channel. Through method of following performance evaluation, advantage and disadvantage of the developed inflatable kayak were compared with those of the abroad product.

The Study of Performance Evaluation Coefficient of Fin-and-Tube Heat Exchangers with Frosting (착상을 수반한 핀-관 열교환기의 성능평가계수에 관한 연구)

  • 최봉준;황준현;신종민
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.2
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    • pp.132-136
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    • 2003
  • For the study of performance evaluation on different shape heat exchangers that have the same energy consumption in a refrigerator, we make performance evaluation coefficient (PEC) which can distinguish performance of different shape heat exchangers. The results were reported in order to compare with for the dry frosting and wet frosting test as various definition of PECs. Results showed that PEC of dry frosting test is higher than that of wet frosting test because attached water droplet increases pressure drop of air-side then this decreases performance of heat exchanger.

A Study on the Practice of Making up Questions on Schools Mathematics Tests (수학과 평가 문항제작의 실제)

  • Jeon, Young-Ju
    • Journal of the Korean School Mathematics Society
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    • v.15 no.2
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    • pp.281-297
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    • 2012
  • Mathematics evaluation is aimed at measuring students' mathematical ability to think and achievement. Moreover, the quality of mathematics education at school is elevated by the test questions analysis and application process. And the starting point of evaluation is to make good test questions. This study is composed of four parts. First, theoretical background associated with making test questions is surveyed. Second, example questions according to the education goals and question-making cautions are presented. Third, four practical stages of making test questions which consist of designing, making the first draft of questions, verifying and making the final draft of questions, are illustrated.

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Evaluation Technology of Electrical and reliableility Characteristics for Outdoor Polymer Insulator Materials (폴리머 절연물 소재의 전기적 밀 복합열화 특성평가 기술)

  • Ahn, Myeong-Sang;Park, Hoy-Yul;Na, Moon-Kyeong
    • Proceedings of the KIEE Conference
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    • 2006.07c
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    • pp.1343-1344
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    • 2006
  • There have been numerous accelerated aging laboratory tests for evaluating suitability of polymeric materials and devices. Aging test for materials and its full scale device has been conducted. Service experience plays a key role in the utility section of composite insulators. A meaningful and reliable accelerated aging test is needed for evaluating composite insulator. During the service these insulators are subjected to aging stress such as humidity, pollution, and electrical field, and erosion and tracking of the weathershed occurs. This paper presents the criteria of reliability evaluation and evaluation facilities for 22.9 kV suspension composite insulator. We adopt the criteria of reliability evaluation consist of two test methods. One is CEA tracking wheel test for examining the tracking and erosion performance of composite insulator. The other is multi-stress aging test for examining effects of environmental factors such as UV, temperature, humidity, etc on composite insulator.

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Development of a Descriptive Paper Test Item and a Counting Formula for Evaluating Elementary School Students' Scientific Hypothesis Generating Ability (초등학생의 과학적 가설생성능력 평가를 위한 서술형 지필과제 및 가설생성능력지수 산출식의 개발)

  • Jo, Eun Byul;Shin, Dong Hoon
    • Journal of Korean Elementary Science Education
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    • v.35 no.2
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    • pp.137-149
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    • 2016
  • The purpose of this study is to develop a descriptive paper test item which can evaluate elementary school students' HGA (scientific Hypothesis Generating Ability) and to propose a counting formula that can easily assess student's HGA objectively and quantitatively. To make the test item can possibly evaluate all the students from 6th graders to 3rd graders, the 'rabbit's ear' item is developed. Developed test item was distributed to four different elementary schools in Seoul. Total 280 students who were in the 6th grade solved the item. All the students' reponses to the item were analyzed. Based on the analyzed data evaluation factors and evaluation criteria are extracted to design a Hypothesis Generating ability Quotient (HGQ). As the result 'Explican's Degree of Likeness' and 'Hypothesis' Degree of Explanation' are chosen as evaluation factors. Also precedent evaluation criteria were renewed. At first, Explican's Degree of Likeness evaluation criterion was turned four levels into three levels and each content of evaluation criterion is also modified. Secondly, new evaluation factor 'Hypothesis' Degree of Explanation' was developed as combined three different evaluation criteria, 'level of explican', 'number of explican' and 'structure of explican'. This evaluation factor was designed to assess how the suggested hypothesis can elaborately explain the cause of one phenomenon. Newly designed evaluation factors and evaluation criteria can assess HGA more in detail and reduce the scoring discordant through the markers. Lastly, Developed counting formula is much more simple than precedent Kwon's equation for evaluating the Hypothesis Explanation Quotient. So it could help easily distinguish one student's scientific hypothesis generating ability.

A Study on Efficient Test & Evaluation Methods in Naval Ship Acquisitions (함정사업 시험평가의 효율적 수행방안에 관한 연구)

  • Kim, Jaeyong;Choi, Woensug;Hong, Sukyoon;Chung, Hyungyun;Song, Jeehun;Im, Wooseok;Kwon, Hyunwung
    • Journal of the Korea Institute of Military Science and Technology
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    • v.19 no.6
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    • pp.703-711
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    • 2016
  • The purposes of this study is to identify the problems arising from current Test & Evaluation process of the naval ship acquisition program and to suggest methods to increase the acquisition efficiency. Considering that the present rule of developmental test &evaluation(DT&E) and operational test & evaluation(OT&E) has caused an inefficiency effect on the acquisition procedures due to the limited practices on it, the DT&E and OT&E procedures through test & evaluation master plan(TEMP) is proposed based on the selective practices of the defense instruction articles. Also, considering characteristics of naval ship acquisitions, efficient procedure systems are derived through case analysis results by comparing each performances of the system. The suggested methods are able to meet the requirements of the changed acquisition environments and also increase efficiency of acquisition systems by adoption of DT&E and OT&E combined test scheme.

Establishing Quantitative Evaluation Standards for the Shape Fitness test of Slacks (슬랙스 형태 적합성 평가의 정량적 평가 기준 설정)

  • Kim, Seonyoung
    • Fashion & Textile Research Journal
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    • v.18 no.5
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    • pp.695-707
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    • 2016
  • This study presents quantitative evaluation standards for the shape fitness test, conducted in the process of the slacks fit test. This study aims to quantify appearance sensory test of slacks for the objectification of qualitative evaluation methods in existing shape fitness tests. The subjects were women of standard body type between the ages of 18 and 24. Slacks differing in their ease in waist girth, hip girth, crotch length and knee length were designed to test their shape fitness. The gap volume distribution between the body and slack, angle of the baseline by body part, and ratio of total thickness from the sideline using 3D human body scan data (which reflect the results of the appearance sensory test) were presented as quantitative evaluation standards. There were less wrinkles in the wrinkle/overstretch and ease categories of the appearance sensory test; in addition, ease was adequate and small enough to comfortably perform basic human activities in the standing upright posture. The gap volume distribution analysis between body and slacks showed that curves increased in the slacks surface along with an increase of ease in slacks and suggested that wrinkles also increased. In the baseline's horizontal categories in terms of a $0^{\circ}$ horizontal angle, the range of angles were evaluated as adequate by the clothing expert group. The total thickness ratio of 0.5:0.5 divides into the sideline from the baseline.

An Empirical Evaluation of Test Data Generation Techniques

  • Han, Seung-Hee;Kwon, Yong-Rae
    • Journal of Computing Science and Engineering
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    • v.2 no.3
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    • pp.274-300
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    • 2008
  • Software testing cost can be reduced if the process of testing is automated. However, the test data generation task is still performed mostly by hand although numerous theoretical works have been proposed to automate the process of generating test data and even commercial test data generators appeared on the market. Despite prolific research reports, few attempts have been made to evaluate and characterize those techniques. Therefore, a lot of works have been proposed to automate the process of generating test data. However, there is no overall evaluation and comparison of these techniques. Evaluation and comparison of existing techniques are useful for choosing appropriate approaches for particular applications, and also provide insights into the strengths and weaknesses of current methods. This paper conducts experiments on four representative test data generation techniques and discusses the experimental results. The results of the experiments show that the genetic algorithm (GA)-based test data generation performs the best. However, there are still some weaknesses in the GA-based method. Therefore, we modify the standard GA-based method to cope with these weaknesses. The experiments are carried out to compare the standard GA-based method and two modified versions of the GA-based method.

A Study of Translation Conformity on Korean Version of a Balance Evaluation Systems Test (한국어판 Balance Evaluation Systems Test의 번역 적합성 연구)

  • Jeon, Yong-jin;Kim, Gyoung-mo
    • Physical Therapy Korea
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    • v.25 no.1
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    • pp.53-61
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    • 2018
  • Background: The process of language translation, adaptation, and cross-cultural validation of tools for use in multiple countries requires the adoption of well-established, comprehensive, and rigorous methodological approaches. Back translation, which is the most recommended method, permits the detection of errors in the translation and the identification of words or phrases that cannot be accurately or literally translated. Objects: The aim of this study was to verify the content validity of a Korean version of a Balance Evaluation Systems test (BESTest) by using a back-translation method. Methods: This research was conducted in six steps: 1) translation of the BESTest into Korean, 2) evaluation of the translation conformity of Korean-translated BESTest, 3) evaluation of the degree of translation comprehension, 4) back translation of Korean BESTest, 5) evaluation of the technical and conceptual equivalence, and 6) completion of the Korean version of BESTest by the translation verification committee. Results: In this study, Korean version of the BESTest achieved a rating of more than 3 (moderate) for translation comprehension, and technical equivalence and conceptual equivalence of back translation were evaluated as 3 (moderate) or more. Conclusion: The Korean version of the BESTest has proven content validity and is an appropriate tool to measure balance function.