• 제목/요약/키워드: Test & Evaluation Method

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알루미늄 차체 하중 시험 방법에 관한 비교 평가 (Comparison and Evaluation of Load test Methods for Aluminum Car Body)

  • 서승일;박춘수;신병천
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2003년도 추계학술대회 논문집(I)
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    • pp.187-191
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    • 2003
  • Aluminum carbody for rolling stocks is light and perfectly recycled, but includes severe defects which are very dangerous to fatigue strength. Static load test has been performed up to date to assess structural safety of the carbody. However, static load test is not sufficient to evaluate fatigue strength of the carbody, because fatigue failure is caused by dynamic load. In this study, the established load test methods for carbody are described and the characteristics of the methods are discussed. Also, a testing method to simulate dynamic loading condition is proposed for evaluation of fatigue strength of the carbody The results by the proposed testing method are compared with the results by the static load test and new findings are discussed.

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공기음 차단성능 평가방법의 KS규격화 방안 (A Draft Korean Standards on the Evaluation Method of Airborne Sound Insulation in Building and Building Elements)

  • 양관섭;이태강;이근희;김선우
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 추계학술대회논문집 I
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    • pp.387-391
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    • 2001
  • In evaluating sound performance of building, it is important to carry on tests and evaluations based upon residential sound performances. Korean Standards include test methods on sound performance, but don't include any code on evaluation methods. Therefore, evaluation methods from Japan or ISO have been used for evaluating sound performance in domestic so far. In this study, a draft of Korean Standards on a sound performance evaluation method in buildings is proposed.

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초음파에 의한 발전소 고온배관재료의 크리프손상 평가 (Creep Damage Evaluation of High-Temperature Pipeline Material for Fossil Power Plant by Ultrasonic Test Method)

  • 이상국;정민화
    • 한국해양공학회지
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    • 제13권2호통권32호
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    • pp.99-107
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    • 1999
  • Boiler high-temperature pipelines such as main steam pipe, header and steam drum in fossil power plants are degraded by creep damage due to severe operationg conditions which are high temperature and high pressure for an extended period time. Such material degradation leads to various component failures causing serious accidents at the plants. Conventional measurement techniques such as replica method, electric resistance method, and hardness test method have such disadvantages as complex preparation and measurement procedures, too many control parameters, and therefore, low practicality and they were applied only to component surfaces with good accessibility. In this paper, artificial creep degradation test and ultrasonic measurement for their creep degraded specimens have been carried out for the purpose of evaluation for creep damage which can occur in high-temperature pipeline of fossil power plant. Absolute measuring method of quantitative ultrasonic measurement for material degradation was established, and long term creep degradationtests using life prediction formula were carried out. As a result of ultrasonic tests for crept specimens, we confirmed that the sound velocity decreased and the attenuation coefficient linearly increased in proportion to the increase of creep fractiin(${\phi}$c).

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임플란트와 상부보철물의 임상적/실험적 부적합 평가에 관한 문헌고찰 (A literature review on clinical/ laboratory misfit evaluation on implant-prosthesis)

  • 김종회;조웅래;고경호;허윤혁;박찬진;조리라
    • 대한치과의사협회지
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    • 제56권9호
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    • pp.462-478
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    • 2018
  • 임플란트와 지대주 간에 허용가능한 적합도를 넘는 부적합을 발견하고 이에 대처하는 것은 중요한 과제이다. 부적합을 임상에서 평가하고 발견하는 방법은 대부분 부적합의 정성적 평가에 치중하고 있으며 술자의 숙련도에 의존하고 있어 정확한 평가방법이라고 하기는 어렵다. 부적합의 정도를 판단하고 원인을 실험적으로 분석하는 방법 중 본 문헌고찰에서는 광탄성 분석법, 유한요소분석법, 스트레인게이지, 미생물 균체 분석 등 조건을 모형화하여 분석하는 모형화법과 사진 측량, 삼차원 좌표 측정, 현미경분석 및 방사선분석을 통해 부적합의 정도를 정밀하게 측정하는 수치법을 각각 설명하고 그 장단점 및 적용의 한계를 분석하였다. 지금까지 살펴본 실험실 부적합 평가 방법들을 장, 단점 및 정확도와 재현성을 기준으로 표로 정리한 것이 Table 3이다. 어떤 방법도 모든 경우에 적용할 수 있을 정도로 완벽하지는 않으므로 평가하고자 하는 부적합의 특성에 따라 적절한 평가방법을 선택하여 적용하는 것이 필요하다고 사료된다.

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한국주부가 가사노동시간과 경제적 가치 평가 (An Evaluation of Time Use and Economic Value of Housework in Korea)

  • 김정희
    • 대한가정학회지
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    • 제31권4호
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    • pp.37-51
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    • 1993
  • The Objects of this study are: 1. To compare the housework time of housewives by region and employment status. 2. To compare the economic value of housework by region and employment status. 3. To evaluate the economic value of housework by each method. The subjects of this study were 815 housewives living in Taegu and Kyungsangpookdo. The statistics used for data analysis were frequency, percentile, T-test, ANOVA and Seheffe test by SPSS PC programs: 1) The average housework time was 7.8hours per day. Full-time housewives spent 8.2hours and employed housewives spent 6.7hours to housework. 2) Partially there were significant difference in economic value of housework by employment status. 3) Estimates of economic value of housework by each method of evaluation are : (unit : won) sample mean method monthly (1) Specialized substitute method 587,080 (2) Overall substitute method 760,640 (3) Opportunity cost method 556,060 (4) Reservation wage method 534,070 (5) Subjective evalution method 644,540

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여성복의 기능성 향상을 위한 착의 평가에 관한 연구 -소매산 높이 변화에 따른 기능성 측정을 중심으로- (A Study on the Evaluation for the Improvement of the Functional Movement of Women′s Wear -with Concentration on the Measurement of Functional Movement according to the Change of Cap Height-)

  • 박선경
    • 복식문화연구
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    • 제12권2호
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    • pp.249-261
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    • 2004
  • This research proves the ROM method (Range Of Motion), which has already been used in other countries, that measures the capacity of exercise and the adaptation of movement of functional garments for special purpose due to change of the height of basic sleeve sloper. Basically, the ultimate goal of the research is to improve the functional pattern design. Firstly, this research proves the proper application of ROM that is used for the evaluation of fitting test. Therefore, according to this research, the company is able to produce the sample that is appropriate to the various purpose for women garments and betters the evaluation of function of garments. Moreover, it suggests that the evaluation of fitting test satisfies the consumers who desire to try better garments and contributes to the competitions among the companies that bring more improvements to the fashion design.

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A Study on the Limits of the Comparative School Record Using the Individual Scholastic Evaluation

  • Chung, Yeon-Soo
    • Communications for Statistical Applications and Methods
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    • 제7권2호
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    • pp.465-473
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    • 2000
  • There is no progress in interpreting the correlation between the high school record and the scholastic aptitude test. This study gives the degree of the linearity between the high school record and the scholastic aptitude test by using the method of the individual scholastic evaluation which was proposed by Chung(1999). The limits of the individual scholastic evaluation are pointed out additionally in inferring the promising individuals having the high scores in the scholastic aptitude test so that the individual scholastic evaluation be used as reference materials when the colleges applying the comparative school record in the entrance exams.

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감쇠계수 산출을 위한 자유 횡동요 감쇠실험 연구 (Experimental Study of the Free Roll Decay Test for the Evaluation of Roll Damping Coefficients)

  • 김남우;김용직;하영록
    • 대한조선학회논문집
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    • 제52권6호
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    • pp.460-470
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    • 2015
  • In general ships and FPSOs, roll damping is very small and consequently roll motion is very large at the roll resonance frequency. Proper evaluation of the roll damping coefficient at the resonance frequency is an important task in the study of roll motion and usually it is done by the analysis of free roll decay tests. The relative decrement method based on energy relation has been used mainly for the evaluation of roll damping coefficient from the roll decay test so far. As another method, the logarithmic decrement method based on equivalent linear decay assumption can be used for the same purpose and it is relatively simple. In this paper, both of the relative decrement method and the logarithmic decrement method are used for the evaluation of roll damping coefficient including quadratic damping from the free roll decay tests, and their results are cross-checked for verifying the obtained damping coefficients. Through applications to a box-type floating body equiped with bilge keels, it is shown that the two methods give almost the same damping coefficients in a practical view point and the cross-check of their results is to be a good tool to prevent a possible error. And also the quantitative effects of the bilge keels on the roll damping of box-type floating body are shown and discussed.

변동풍력의 연직분포를 고려한 건축물의 풍하중 평가 (The Wind Load Evaluation on Building Considering Vertical Profile of Fluctuating Wind Force)

  • 류혜진;신동현;하영철
    • 대한건축학회논문집:구조계
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    • 제35권7호
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    • pp.157-164
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    • 2019
  • The wind tunnel test makes it possible to predict the wind loads for the wind resistant design. There are many methods to evaluate wind loads from data obtained from the wind tunnel test and these methods have advantages and disadvantages. In this study, two of these methods were analyzed and compared. One is the wind load evaluation method by fluctuating displacement and the other is the wind load evaluation method considering vertical profile of fluctuating wind force. The former method is evaluated as the sum of the mean wind load of the average wind force and the maximum value of the fluctuating wind load. The latter method is evaluated as the sum of the mean wind load and maximum value of the background wind load, and the maximum value of the resonant wind load. Two methods were applied to the wind tunnel test to compare the evaluated wind loads according to the two methods, with a maximum difference of about 1.2 times. The wind load evaluated by the method considering vertical profile of the fluctuating wind force (VPFWF) was larger than the wind load evaluated by the method by fluctuating displacement (FD). Especially, the difference of the wind load according to the two methods is large in the lower part of the building and the wind load is reversed at a specific height of the building. VPFWF of evaluating resonant wind loads and background wind loads separately is more reasonable.