• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 가을 학술발표회 논문집
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• pp.108-113
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• 1996

Concrete mix degign and adjustments are somewhat complicated and time-consuming tasks in which various uncertainties and errors are involved and depend on the quality control test results. In this paper, as a tool to minimize the uncertainties and errors the neural network is applied to the concrete mix design. Input data to train and test the neural network are obtained from the results of design and adjustments following the concrete standard specifications of Korea. The results show that neural networks have a strong potential as a tool for concrete mix design.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2018년도 전력전자학술대회
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• pp.308-309
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• 2018

This paper proposes new D/A(Digital to Analog) Design method for improving accuracy in high-performance test equipment. The proposed new D/A design can improve accuracy of the equipment even with low-resolution D/A converters. The validity of proposed D/A design is verified by analysis and experiment.

• 한국추진공학회지
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• 제18권1호
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• pp.85-90
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• 2014

액체 추진 엔진 개발을 위해서는 서브시스템인 연소기 개발이 선행되어야 하고 설계 및 제작된 연소기의 성능 검증은 연소기 연소시험설비(CCTF)에서 수행된다. 연소기 연소시험설비는 로켓 엔진의 연소기를 개발하기 위한 시험 설비로 산화제로는 액체산소(Liquid Oxygen)를 사용하고 연료로는 케로신(Kerosene)을 사용한다. 이러한 추진제는 질소가스를 사용하여 고압으로 추진제 런탱크를 가압하여 연소실로 공급하게 된다. 우주센터에 구축 예정인 연소기 연소시험설비에 대한 상세설계가 수행되었으며, 본 논문에서는 고압가스 공급시스템에 대한 설계 결과를 소개하고자 한다.

• 한국정보과학회논문지:시스템및이론
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• 제31권3_4호
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• pp.160-169
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• 2004

IC 집적기술이 고도로 발달하면서 출현한 SOC(System On a Chip)는 미리 설계된 코어를 재 사용하는 모듈러 기법을 회로 설계 과정에 도입시켰고, 따라서 테스트 설계에도 모듈러 기법이 도입되었다. 이러한 SOC 테스트에 소요되는 비용의 최소화를 위해서는, SOC 테스트 구조의 핵심 구성요소인 코어 테스트 wrapper의 테스트 시간과 테스트 면적을 동시에 최적화시킬 수 있는 설계 기법이 필요하다. 본 논문에서는 최소 비용의 SOC 테스트를 위한 효율적인 코어 테스트 Wrapper 설계 기법을 제안한다. 본 논문에서 제안하는 기법은 기존의 기법들이 각기 가지고 있는 장점들을 하나로 취합하고 더욱 발전시킴으로써 필드에서 실재적으로 사용될 수 있는 효율적인 코어 테스트 wrapper 설계 기법이다.

• 대한조선학회논문집
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• 제52권6호
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• pp.428-434
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• 2015

The objective of the present study is to analyze the results of the trial-test for the full-scale driving pump, which is arranged in the LCT (Large Cavitation Tunnel). Firstly, the reasons of selecting the final design pump are introduced in terms of the performance analysis in model tests. The trial-test items for the full-scale driving pump are measurements of output current/voltage at the inverter of the main motor and the flow velocity in the LCT test section. The test results show the increase in flow rate of about 10.7% and the decrease in pump head of about 26%, compared with those of final design-pump specification. The motor power has the margin of about 22%. The performance analysis for the full-scale pump is conducted using the commercial code (CFX-10). The delivered power calculated with CFX-10 shows good agreement with that extracted from the full-scale pump test. It is found that CFX-10 is useful to analyze a full-scale pump.

• 한국정보과학회논문지:소프트웨어및응용
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• 제34권3호
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• pp.212-218
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• 2007

아직까지 소프트웨어 개발조직에서는 사전검증 활동 및 충분한 테스트 설계가 수행되지 않고 있으며, 따라서 개발 초기에 식별, 수정될 수 있는 결함들까지 테스트시 검출되기 때문에 투입 노력 대비 테스트의 효율성은 떨어진다. 이러한 문제의식을 바탕으로 본 논문은 구현이전단계에서의 사전검증이 수행 되지 않고, 테스트 케이스 설계가 충분히 진행되지 않은 경우에 테스트의 효율성을 향상시킬 수 있는 방법을 실사례를 통해 제안하고 있다. 테스트 단계에서의 코드 리뷰와 코드 품질 분석을 통해 테스트 우선순위 선정, 테스트별 테스트 케이스 설계 등의 주요 활동과 테스트팀과 개발팀과의 역할을 구체적으로 제시한다.

• International Journal of Quality Innovation
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• 제7권1호
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• pp.177-194
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• 2006

This research investigates the status of environmental design implementation in Taiwan's industries (Certified by ISO 14001) by employing questionnaire survey. The correlation between the degree of environmental design implementation in Taiwan's industries and the relevant entrepreneurial characteristics are examined. Twenty-six environmental design principles in four phases: design, manufacturing, sales and transportation, and disposal are used to define and assess the current status of environmental design. The data analysis methods applied to this research includes descriptive statistics, T-test, Chi-square test, and single-factor analysis of variance (ANOVA). It is evident that 21 out of the 26 environmental design principles are frequently and consistently employed by the manufacturers in Taiwan. The results indicate that environmental design implementation is becoming mature in Taiwan's industries.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 말뚝기초 학술발표회
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• pp.65-84
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• 2000

Europe and US which have more restrictive regulations than Korea about the noise and vibration during construction are using Auger-cast Pile to reduce the problem relating with noise and vibration. However Auger-cast Pile has problems like difficult quality control and low bearing capacity. In Europe, Displacement in-situ concrete Pile has been used to sove that problems since 1990s, and Korea has performed the test construction in 1997 and it has been used as the real structural foundation since 1998. Test and real construction results verified that the allowable capacity of the pile(diameter = 410mm) is between 70 and 100ton. Though De Beer & Van Imps design method utilizing CPT result is used to calculate the bearing capacity of the Displacement in-situ Pile, Korea is dependant upon the SPT as the sounding test, so design method utilizing SPT result is necessary to promote the application of the pile. To find out reasonable design method using SPT result, rearing capacity of the pile constructed in sand and clay in Korea was calculated using Meyerhof, SPT-CPT translation method, Nordlund, Douglas and DM-7 method, and the calculation results were compared to the load test result. Analysis result shows that SPT-CPT translation method is more reliable than others and economical design can be possible because it considers efficiently the friction capacity of Displacement in-situ Pile.

• 마이크로전자및패키징학회지
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• 제18권2호
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• pp.35-41
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• 2011

Recently, board level solder joint reliability performance of IC packages during drop impact becomes a great concern to semiconductor and electronic product manufacturers. The handheld electronic products are prone to being dropped during their useful service life because of their size and weight. The IC packages are susceptible to solder joint failures, induced by a combination of printed circuit board (PCB) bending and mechanical shock during impact. The board level drop testing is an effective method to characterize the solder joint reliability performance of miniature handheld products. In this paper, applying the JEDEC (JESD22-B111) standard present a finite element modeling of the FBGA. The simulation results revealed that maximum stress was located at the outermost solder ball in the PCB or IC package side, which consisted well with the location of crack initiation observed in the failure analysis after drop reliability tests.

• 한국신뢰성학회지:신뢰성응용연구
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• 제14권4호
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• pp.220-224
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• 2014

A Bayesian zero-failure reliability demonstration test method for products with Weibull lifetime distribution is presented. Inverted gamma prior distribution for the scale parameter of the Weibull distribution is used to design the Bayesian test plan and selecting a prior distribution using a prior test information is discussed. A test procedure with zero-failure acceptance criterion is developed that guarantee specified reliability of a product with given confidence level. An example is provided to illustrate the use of the developed Bayesian reliability demonstration test method.