• 제목/요약/키워드: lab testing

검색결과 351건 처리시간 0.031초

Design of RF coupler for KIRAMS-13;Korea Institute of Radiological & Medical Sciences-13

  • Jung, In-Su;An, Dong-Hyun;Kim, Yu-Seok;Yang, Tae-Gun;Kim, Jea-Hong;Jang, Hong-Seok;Hong, Bong-Hwan;Lee, Min-Yong;Hong, Sung-Seok;Chai, Jong-Seo;Oh, Bong-Hun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.2203-2205
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    • 2003
  • KIRAMS-13, the first medical cyclotron developed by domestic technique, is used to produce radio-isotope such as $^{18}F$ whose life time is relatively short through test operation. For high-power operation of charged particle accelerators, the power coupler must withstand enormous stresses due to charging induced by high RF power passing through. High-power RF testing with peak power in excess of 30kW has been performed on prototype power coupler for KIRAMS-13 normal conducting cavities. CST MICROWAVE STUDIO(CST MWS) is used for fundamental RF Design, and power coupler is manufactured according to fundamental power coupler design requisite. The qualification of the couplers has occurred for the time being only in a limited set of conditions as the available RF system and control instrumentation are under improvement.

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고압 커패시터의 고장 분석을 통한 신뢰도 예측 (Reliability Estimation of High Voltage Ceramic Capacitor by Failure Analysis)

  • 양석준;김진우;신승우;이희진;신승훈;유동수;장석원
    • 비파괴검사학회지
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    • 제21권6호
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    • pp.618-629
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    • 2001
  • 본 논문은 고압 커패시터의 고장분석과 신뢰성 예측 결과를 다루고 있다. 부품의 수명과 고장률을 예측하기 위해서 두 가지 방법으로 고장 모드와 고장 메커니즘을 연구하였다 에폭시 수지로 성형된 고압 커패시터가 절연내압 시험 하에서 저항이 제로로 되는 고장에 대하여, 근본원인 고장분석 체계를 효과적으로 수립함으로써 고장 메커니즘의 원인을 분석하였다. 특히 세라믹-에폭시 계면에서의 절연파괴 고장 현상이 강조되었으며, 본 연구에서 얻어진 결과의 타당성은 마그네트론에 장착된 고압 커패시터의 열사이클 시험 수행에 의한 가속시험 결과로부터 입증되었다. 시험 결과들은 결함이 있는 로트를 신속히 규명하고 $B_{10}$ 수명을 결정하는데 유용하게 사용할 수 있다. 또한, 유전체의 절연파괴에 대해서 부하-강도 간섭모델을 이용하여 고장률을 예측하였다.

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ESTEREL 임베디드 소프트웨어를 위한 모델 기반 테스트 기법 연구 (A Study of the Model-based Testing for Embedded Software in ESTEREL)

  • 양진석;김진현;심재환;김창진;최진영
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2005년도 가을 학술발표논문집 Vol.32 No.2 (2)
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    • pp.337-339
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    • 2005
  • 본 논문에서는 임베디드 시스템의 제어를 위해 동기화 언어인 에스테렐로 개발된 소프트웨어가 소프트웨어 요구사항을 만족하는지 확인하기 위한 Model-based Test(MBT) 프레임 워크를 제안한다. 제안된 프레임 워크를 기반으로 작성한 프로토 타입의 테스트 도구는 요구사항 모델을 창조하여 On-the-fly 방법을 통해 테스트 케이스를 랜덤하게 자동으로 생성하여 소프트웨어에 대하 테스트를 자동으로 수행한다. 간단한 case study로 레고 마인드스톰 로봇 제어 소프트웨어에 MBT를 수행하고 그 결과를 확인한다.

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반사균열 저감을 위한 Saw and Seal 공법의 줄눈재 평가 및 효과에 관한 연구 (A Study on Sealant Evaluation and Effectiveness of Saw and Seal Method for Reducing Reflection Cracking)

  • 서용환;서영찬;배종오;전범준
    • 한국도로학회논문집
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    • 제14권4호
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    • pp.73-81
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    • 2012
  • PURPOSES : The purpose of this study is to select the proper sealing method and to see the performance of the saw and seal method for concrete rehabilitation based on accelerated pavement testings and lab tests. METHODS : Two accelerated pavement testings were conducted. One is to select proper sealing method of the asphalt joints and the other is to see the performance of the saw and seal method. Lab tests were conducted to select proper sealing method and a test section was constructed to see the field performance. RESULTS : The result of the first accelerated pavement testing indicated that the adhesive preformed sealants showed good performance when asphalt layer was rutted and in terms preventing from water infiltration. The second acceleration test indicated that the saw and seal method using the adhesive preformed sealant showed much better performance than the control. In the lab test bitumen, rubber and epoxy showed good performance as the adhesive. CONCLUSIONS : Saw and Seal method using the adhesive preformed sealant would markedly reduce the joint damage on the asphalt overlay.

HILS를 이용한 함정의 관성항법장치 전달정렬 환경 모의 기법 (A Simulation Technique of the Shipboard INS Transfer Alignment Environments using Hardware-In-the-Loop Simulation)

  • 김운식;양태수;김상하
    • 한국군사과학기술학회지
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    • 제14권2호
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    • pp.181-188
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    • 2011
  • A simulation technique, which simulate dynamic motion and communication environments of ship in the lab, is needed in order to reduce the testing cost when we evaluate the transfer alignment performance of shipboard INS. Hardware-In-the-Loop Simulation(HILS) can be used as an effective test method for those system because it can provide flexible and realistic simulation environments, various test scenario, and repeated test environment in the lab without additional cost and person. This paper presents the methods for implementing the real time HILS environment for testing transfer alignment performance of shipboard INS. It includes real time executive for controlling realtime simulation and calculating the ship motion, communication method for interfacing between the systems, and coordinate transformation method for converting real ship coordinate attitude data to lab coordinate attitude data.

Choice of Efficient Sampling Rate for GNSS Signal Generation Simulators

  • Jinseon Son;Young-Jin Song;Subin Lee;Jong-Hoon Won
    • Journal of Positioning, Navigation, and Timing
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    • 제12권3호
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    • pp.237-244
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    • 2023
  • A signal generation simulator is an economical and useful solution in Global Navigation Satellite System (GNSS) receiver design and testing. A software-defined radio approach is widely used both in receivers and simulators, and its flexible structure to adopt to new signals is ideally suited to the testing of a receiver and signal processing algorithm in the signal design phase of a new satellite-based navigation system before the deployment of satellites in space. The generation of highly accurate delayed sampled codes is essential for generating signals in the simulator, where its sampling rate should be chosen to satisfy constraints such as Nyquist criteria and integer and non-commensurate properties in order not to cause any distortion of original signals. A high sampling rate increases the accuracy of code delay, but decreases the computational efficiency as well, and vice versa. Therefore, the selected sampling rate should be as low as possible while maintaining a certain level of code delay accuracy. This paper presents the lower limits of the sampling rate for GNSS signal generation simulators. In the simulation, two distinct code generation methods depending on the sampling position are evaluated in terms of accuracy versus computational efficiency to show the lower limit of the sampling rate for several GNSS signals.

Characterizing the damage mechanisms in mode II delamination in glass/epoxy composite using acoustic emission

  • Dastjerdi, Parinaz Belalpour;Ahmadi, Mehdi
    • Structural Engineering and Mechanics
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    • 제67권5호
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    • pp.545-553
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    • 2018
  • Mode II delamination propagation is an important damage mode in laminated composites and this paper aims to investigate the behavior of this damage in laminated composite materials using acoustic emission (AE) technique. Three different lay-ups of glass/epoxy composites were subjected to mode II delamination propagation and generated AE signals were recorded. In order to investigate the propagation of delamination behavior of these specimens, AE signals were analyzed using Wavelet Packet Transforms (WPT) and Fast Fourier Transform (FFT). In addition, conventional AE analyses were used to enhance understanding of the propagation of delamination damage. The results indicate that different fracture mechanisms were the main cause of the AE signals. The dominant mechanisms in all the specimens were matrix cracking, fiber/matrix debonding and fiber breakage, with varying percentage of the damage mechanisms for each lay-up. Scanning Electron Microscopy (SEM) observations were in accordance to the AE results.

감응순항제어장치(ACC)의 안전성 평가 (Safety Evaluation of the Adaptive Cruise Control System)

  • 용부중;심소정;윤경한
    • 한국자동차공학회논문집
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    • 제15권2호
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    • pp.159-164
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    • 2007
  • The Advanced Safety Vehicle (ASV) allows drivers not only convenience and safety, but also many useful services provided by the Telematics technology. Since ASV is expected to be widely used in the near future, it is necessary to ensure the safety of ASV systems. Among several aspects of ASV, this paper investigates the safety of the Adaptive Cruise Control (ACC) system. Field tests are carried out under the domestic roadway and traffic conditions, according to International Standard Organization (ISO) requirements for ACC. The test data are analyzed whether the requirements are adequate for domestic circumstances, and the suggestions for findings are given.

HU-125C 전자현미경에 있어서 카메라 상수의 변화 및 상의 회전에 대한 조사 (Variation of Camera Constant and Image Rotation in HU-125C Electron Microscope)

  • 최주;예길촌
    • Applied Microscopy
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    • 제4권1호
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    • pp.1-4
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    • 1974
  • Hitachi HU-125C 전자현미경에 있어서 각 렌즈 전류의 연동에 따른 카메라 상수의 변화를 주사하였다. 시료의 높이 변화가 카메라 상수의 변동에 현저한 영향을 끼치고 있음도 알 수 있었다. 전자회절상과 시편상의 회전은 결정시료를 사용하여 측정하였다. 금속박막을 조사연구함에 있어서 전자현미경의 실제석인 조작방안을 적정화하기 위한 몇 가지 문제를 조사하였다. 본 실험진행을 전자현미경 작업을 통하여 크게 도와 준 김수철씨에게 진심으로 감사드립니다.

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