• 제목/요약/키워드: Evaluate

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계장화 압입시험을 이용한 차륜의 강도평가 (The Strength Evaluation of Wheel for Railway Rolling Stock Using Instrumented Indentation Test)

  • 김철수;안승호;정광우;박신호;강길현
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 춘계학술대회 논문집
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    • pp.1607-1612
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    • 2007
  • To assure safe usage of railway rolling stock, it is important to evaluate the strength of the wheel which is core part in bogies. However, conventional standard testing methods using destructive technique could not evaluate mechanical properties of degraded wheels during rolling stock maintenance work. Instrumented indentation test is a new way to evaluate nondestructively the strength of mechanical components by analyzing indentation load-depth curves. In this study, to evaluate tensile strength of the wheel, instrumented indentation test is performed nondestructively according to KS B 0950. Furthermore, test results are examined by tensile test in accordance with KS R 9221.

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생산성 향상을 위한 대안들의 비교 평가 시뮬레이션 사례연구 (A Simulation Study for Comparison and Evaluation of Alternative Plans for the Productivity Improvement)

  • 김원경
    • 한국시뮬레이션학회논문지
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    • 제10권1호
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    • pp.51-62
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    • 2001
  • For the productivity improvement, it is necessary to analyze problem of the system and evaluate alternative plans. But, it if hard to experiment and evaluate alternative plans in real existing system. Therefore, it is necessary to synthetically analyze and evaluate alternative plans using simulation and statistical analysis method. In this case study, as a simulation language, Promodel is used to compare and evaluate four alternatives which are considered to improve the productivity of an object system. The object system is constituted of a pretreatment line and a painting line. The purpose of this study is to analyze whether the decrease of the down time in pretreatment line can be effective to the productivity improve comparing with exiting system and other alternatives. The other purpose is to choose an alternative that has the best productivity improvement. The results of the simulation show that the possibility of improvement in productivity by decreasing the down time of pretreatment line. Two-Stage Bonferroni Procedure is used to choose the best alternative.

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역량스펙트럼 방법과 수정변위계수법을 이용한 다경간 교량의 내진성능 평가 (Seismic Performance Evaluation of Multi-Span Bridges using CSM and modified DCM)

  • 남왕현;송종걸;정영화
    • 산업기술연구
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    • 제26권B호
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    • pp.119-126
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    • 2006
  • Capacity spectrum method(CSM) of ATC-40(1996) and displacement coefficient method(DCM)of FEMA-273(1997) are applied to evaluate the seismic performance of bridges. In this study, equivalent response is obtained from nonlinear static analysis for the 3spans continues bridge and nonlinear maximum displacement response is calculated using CSM and DCM. Nonlinear maximum displacement response of DCM is larger than this of CSM. It is method that DCM can evaluate target displacement and ductility of structural to be easy and simple, but tend to overestimate the maximum displacement response. Therefore, this method is mainly used at preparation design level to evaluate the structural response. It is not desirable to evaluate the seismic performance using DCM.

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비선형 영역에서의 재료감쇠비 측정을 위한 주파수-위상각법 (Frequency-Phase Method to Measure Material Damping in a Nonlinear Range)

  • 우규석;조성호
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2001년도 봄 학술발표회 논문집
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    • pp.533-540
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    • 2001
  • Material damping is an important parameter to evaluate the site response by a dynamic loading. Currently the material damping of the subgrade is mainly determined by a resonant column testing. Typical methods to evaluate material damping include half-power bandwidth method and free-vibration decay method. In the large strain range, the half-power bandwidth method gives an erratic damping factor, because the method is based on the assumption of the linear behavior of a specimen. The free-vibration decay method has also limitations in that the damping factors vary with the range of cycles in calculation, and also in that the specific shear strain can not be designated for the free vibration. In this study, the frequency-phase method, which was developed to evaluate material damping of a beam simply supported, is introduced to evaluate the material damping by the resonant column testing. Also, the comparison among half-power method, free-vibration decay method and the frequency-phase method is provided for a remolded sand.

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The Total Ranking Method from Multi-Categorized Voting Data Based on Analytic Hierarchy Process

  • Ogawa, Masaru;Ishii, Hiroaki
    • Industrial Engineering and Management Systems
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    • 제1권1호
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    • pp.93-98
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    • 2002
  • It is important to evaluate the performance of candidates mathematically from various aspects, and reflect it on decision making. In decision making, we judge the candidates through two steps, classification of objects and comparison of objects or candidates with plural elements. In the former step, Analytic Hierarchy Process (AHP) is useful method to evaluate candidates from plural viewpoints, and in the later step, Data Envelopment Analysis (DEA) is also useful method to evaluate candidates with plural categorized data. In fact, each candidate has plural elements, nevertheless it has been more important to evaluate from various aspects in IT society. So, we propose a new procedure complementing AHP with DEA.

손 기능에 관한 고찰 (A Review of Hand Function)

  • 이선명
    • 대한물리치료과학회지
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    • 제9권4호
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    • pp.155-168
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    • 2002
  • The purpose of study to know hand function in order to prevent disability or handicap. The ability to perform precise refined movements of hand is an important human function. Improvement in object manipulation is common goal of therapist. The ability to manipulate an object in the hand is need for many functional tasks, including writing, handling coins, small objects and ADL skills. Therapists have commonly used hand grip and pinch strengths as baseline measures to evaluate hand function. The patterns of grasps are precision grasp, power grasp, hook grasp, spherical grasp, sylindrical grasp, disc grasp, pinch, three point pinch and tip pinch. And the motion of in-manipulation are finger to palm translation, palm to finger, shift, simple rotation and complex rotation. The hand function are include to evaluate of ROM, sensation, muscle strength of hand. It used to evaluate of decision of effect and suppose of disability and acceptance of vocation. Good evaluation is need to pretreatment and baseline of treatment and help to evaluate of effect on treatment.

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Machine Learning-Based Programming Analysis Model Proposal : Based on User Behavioral Analysis

  • Jang, Seonghoon;Shin, Seung-Jung
    • International journal of advanced smart convergence
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    • 제9권4호
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    • pp.179-183
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    • 2020
  • The online education platform market is developing rapidly after the coronavirus infection-19 pandemic. As school classes at various levels are converted to non-face-to-face classes, interest in non-face-to-face online education is increasing more than ever. However, the majority of online platforms currently used are limited to the fragmentary functions of simply delivering images, voice and messages, and there are limitations to online hands-on training. Indeed, digital transformation is a traditional business method for increasing coding education and a corporate approach to service operation innovation strategy computing thinking power and platform model. There are many ways to evaluate a computer programmer's ability. Generally, piecemeal evaluation methods are used to evaluate results in time through coding tests. In this study, the purpose of this study is to propose a comprehensive evaluation of not only the results of writing, but also the execution process of the results, etc., and to evaluate the programmer's propensity habits based on the programmer's coding experience to evaluate the programmer's ability and productivity.

신경회로망을 이용한 터빈로타 디스크 키웨이의 결함 검출 (Ultrasonic Flaw Detection in Turbine Rotor Disc Keyway Using Neural Network)

  • 손영호;이종오;윤운하;이병우;서원찬;이종규
    • 비파괴검사학회지
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    • 제23권1호
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    • pp.45-52
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    • 2003
  • 최근 터빈 로타 디스크 키웨이에서 많은 응력부식균열이 발견되었으며, 터빈설비의 중대한 파손을 예방하기 위해 이러한 균열은 조기에 검출 및 평가되어야 한다. 본 연구에서는 초음파탐상의 RF(radio frequency) 신호를 역전파 알고리즘에 근거한 신경회로망에 적용하여 키웨이 주변의 균열에 대한 위치, 크기 및 방향성을 평가하였다. 각 반사영역에서 수신된 여러개의 피크로 나타나는 RF 신호를 각 반사영역에 대해 하나의 최대 피크를 가지도록 처리한 후, 트랜스듀서의 위치 정보와 각 반사파의 도달시긴이 들어있는 주사 데이터를 작성하였다. 이 주사 데이터로부터 각 반사영역 사이의 시간차이와 트랜스듀서의 위치 정보를 신경회로망에 적용한 결과 키웨이에서 시작된 균열의 위치, 크기 및 방향성을 평가하는데 유용함을 알 수 있었다.

각국 표준 규격에 따른 시멘트 강도 비교실험 (Comparison of Cement Strength According to Standard Units)

  • 김남호;정재동;이한봉
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1990년도 봄 학술발표회 논문집
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    • pp.20-23
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    • 1990
  • In order to evaluate the difference of testing results in the standards on the compressive strength of various countries, we have compared the testing results of the compressive and flexural strength, one of the most important properties of cement, obtained on the various standards(KS, JIS, BS, ASTM) and the statistical method was used to evaluate the results.

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부식 촉진실험에 의한 철근방식 연구 (Rapid Corrosion Test for Concrete Reinforcing Steels)

  • 윤강훈;이상국;정영수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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    • pp.671-675
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    • 2000
  • The purpose of this research is to evaluate the performance of various kind anticorrosives which is developed to enhance the capacity of anticorrosives in several conditions of salty reaction, and evaluate corroded state according to various amounts of chloridized material. Beside, to exam Zincspray for Cathodic Protection System evaluation.

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