• ETRI Journal
• /
• 제31권2호
• /
• pp.209-214
• /
• 2009

In this paper, we propose a novel test methodology for the detection of catastrophic and parametric faults present in analog very large scale integration circuits. An automatic test pattern generation algorithm is proposed to generate piece-wise linear (PWL) stimulus using wavelets and a genetic algorithm. The PWL stimulus generated by the test algorithm is used as a test stimulus to the circuit under test. Faults are injected to the circuit under test and the wavelet coefficients obtained from the output response of the circuit. These coefficients are used to train the neural network for fault detection. The proposed method is validated with two IEEE benchmark circuits, namely, an operational amplifier and a state variable filter. This method gives 100% fault coverage for both catastrophic and parametric faults in these circuits.

• 한국컴퓨터정보학회논문지
• /
• 제20권10호
• /
• pp.45-51
• /
• 2015

In this paper, we propose a way to reduce the SW reliability test time and human errors by utilizing the Lean Six Sigma methodology as a troubleshooting tool. Recently, SW technology is rapidly changing and the importance of SW management has been recognized. Accordingly, the SW reliable test for the SW development outcomes in one of the methods for SW quality improvement is required. However, it consumes a lot of development costs, has the time constraints and human errors in SW reliable test, so, it is difficult to meet the requirements for SW test.

• 한국학교수학회논문집
• /
• 제12권1호
• /
• pp.71-97
• /
• 2009

공간능력 향상을 꾀하는 학교현장에서 도구로써 사용할 수 있는 교구의 효과를 파악하는 것은 현장의 수업을 안내하기 위해 필요하다. 학생의 공간능력을 향상시키기 위한 수업의 구성을 위해 우선 학습 자료와 검사지의 개발 필요성이 제기되었다. 공간능력에 관련된 선행연구를 바탕으로 교구를 활용하는 5차시의 귀납적 수입모형과 공간능력의 하위요소인 공간시각화와 공간방향화에 각각 10문항, 15문항으로 모두 25문항의 검사지가 고안되었다. 경기도에 위치한 중학교에서 중간고사 성적이 동질집단인 4개 반 152명을 대상으로 연구를 수행하여 얻은 자료를 바탕으로 평가문항에 대한 난이도, 변별도, 신뢰도가 조사되었고, 개발된 학습자료의 수정과 보완이 이루어졌다. 차후 공간능력을 다루는 후속연구소에서 그들의 연구목적에 따라 한층 수정 보완된 문항개발이 더욱 다양하게 이루어지길 기대한다.

• 공업화학
• /
• 제20권2호
• /
• pp.177-185
• /
• 2009

자동차용 써모스타트 하우징 피팅부상의 침전물(스케일)에 대한 고장분석을 실시하였다. 에너지분산형분석기와 전자현미분석기를 이용하여 침전물이 부동액의 주요 첨가제 성분임을 확인하였다. 자세한 유기성분 분석을 위해 열분해 기체크로마토그래피/질량분석을 수행한 결과, 침전물의 주성분이 벤조산이며, 소량의 아세토페논, 벤젠 및 페닐계 화합물 등으로 이루어져 있음을 확인하였다. 더불어 침전물 생성 원인은 알루미늄 하우징과 고무호스 사이에 존재하는 틈새 공간에 부동액 성분의 침전에 따른 틈새부식에 기인한 것으로 판단된다. 이런 결과를 바탕으로 하여 써모스타트 하우징상의 침전물 생성과 틈새부식을 재현할 수 있는 가속시험기법을 개발하였다. 가속인자(온도, 습도)를 변화시키면서 실제 가동조건을 묘사하였다. 가속시험에서 얻은 침전물을 성분 분석을 통해 완벽히 재현되었음을 확인하였다.

• Journal of the Korean Wood Science and Technology
• /
• 제41권2호
• /
• pp.164-172
• /
• 2013

The purpose of this research was development of quantitative ultrasonic test methodology for detecting internal defects in members of ancient wooden building. Connection part between wooden members and/or contacted or hidden part by wall of ceiling or other construction materials make it hard to apply direct way of ultrasonic test. So indirect way of ultrasonic test needed to be applied. Test methodology with newly developed prototype of ultrasonic system was proposed. Homogeneous material with polypropylene was also tested for establishing the criterion. Results showed that TOF(time of flight)-energy and pulse length were found out to be proper ultrasonic parameters for predicting depth of defect in wood different from polypropylene. It was not possible to directly apply prediction equation derived from polypropylene. Newly established prediction equation shows coefficient of determination of 0.73 for wood. Finally, defect of replaced rafter members was predicted with the coefficient of determination of 0.32. Various aspects of ultrasound propagation in wood including anisotropy need to be carefully considered to raise up the prediction accuracy.

• 한국산학기술학회논문지
• /
• 제8권2호
• /
• pp.201-206
• /
• 2007

본 논문에서는 NoC(Network-on Chip) 구조로 구현된 core-based 시스템에 대한 효율적인 저전력 테스트 방법을 제안한다 NoC의 라우터 채널로 전송되는 테스트 데이터의 전력소모를 줄이기 위해서 스캔 벡터들을 채널 폭만큼의 길이를 갖는 flit으로 분할하고 nit간 천이율(switching rate)이 최소화 되도록 don't care 입력을 할당하였다. ISCAS 89 벤치마크에 대하여 실험을 한 결과, 제안된 방법은 약 35%의 전력 감소를 나타내었다.

• 한국군사과학기술학회지
• /
• 제14권6호
• /
• pp.1031-1036
• /
• 2011

In this paper, we have proposed a methodology which can test and evaluate on system level in development phase of command guided missile system. Test and evaluation play a significant role in the development of weapon system, providing the means for determining to what extent the weapon system satisfies its requirements, whether it functions normally in the operational environment. In case of command guided missile having seeker, the missile communications link provides data to allow the missile to fly an efficient trajectory toward target. Therefore, it is very important to test and evaluate for data link between missile and radar on whole system aspect. we introduce the concept and devices for system level test and evaluation of command guided missile system.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2003년도 ICCAS
• /
• pp.706-710
• /
• 2003

In this paper, we will present brief design feature, implementations, and tests for verification of KOMPSAT-2 simulator, which is a subsystem of KOMPSAT-2 MCE. SIM is implemented on PC server to minimize costs and troubles on embedding onboard flight software into SIM, OOA/OOD methodology is employed to maximized S/W reusability, and XML is used for S/C characteristics, TC, TM and Simulation data instead of commercial DB. Consequently, we can reduce costs for the system, efforts embedding flight software, and maximize software reusability. SIM subsystem test was performed successfully.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2000년도 추계종합학술대회 논문집(1)
• /
• pp.441-444
• /
• 2000

This paper covers the performance testing for layer 3 Ethernet switch based on various methodologies by which we can measure essential metrics such as throughput, latency, frame loss rate, and back to back frames. In the first place, layer 2 and layer 3 switch evolution is introduced followed by description of IP packet switching in layer 3 switch. And then, the above test metrics and test methodologies are illustrated as well. At last, we conduct the performance testing for layer 3 switch in case of transmitting packets of 64, 128, 256, 512, 1024, 1280, and 1518 byte size and analyze then results.

• Communications for Statistical Applications and Methods
• /
• 제12권1호
• /
• pp.11-18
• /
• 2005

Assume that the life times of the units under test follow the Rayleigh distribution and the test is terminated at a pre assigned time. Acceptance sampling plans are developed for this situation. The minimum sample size necessary to ensure the specified average life are obtained and the operating characteristic values of the sampling plans and producer's risk are given. An example is given to illustrate the methodology.