• 한국세라믹학회지
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• 제27권3호
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• pp.321-328
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• 1990

For the reliability analysis of Sin/Hip silicon nitride, such as Weibull modulus m, scale parameter $\sigma$0, and Batdorf crack density coefficient kB were obtained by 4-point MOR test. And its theoretical failure probabilities under arbitrary stress state were predicted using finite element analysis and KARA II reliability analysis program, which was programmed for both surface adn volume flaws. For the verification of this theoretical results, the experimental failure probabilities were measured using ring-to-ring tests at room temperature as well as 4-point MOR tests at 100$0^{\circ}C$, and were compared with theoretical failure probabilities.

• 전자공학회논문지A
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• 제31A권5호
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• pp.50-57
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• 1994

The analysis of the two-tone intermodulation distortion of multistage two-ports with gain and mismatching losses is presented with simplified two-port analyses and statistical viewpoint. The uncertainty obtained from unknown phase angles of the intermodulation distortion signals to the system designer is reduced using stochastic process, hence improving the accuracy of the solution. Based on the dc power dependance of third-order intercept point of each stage, the new efficient method for improving the total intercept point is also suggested with only the relation of dc power and available power gain criteria. Experimental verification on specific amplifiers used for cellular mobile communication comparing predicted and measured intercept points for various power conditions is presented.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.1377-1382
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• 1990

In Multi-Layer Perceptron (MLP) which realizes continuous mappings, the output errors is directly affected by the weight errors which may be caused by the limited precision of digital or analog hardware in implementations. So, it is important to study the sensitivity due to the perturbation of connection weights between neurons. In this paper, we derive a sensitivity function to the statistical weight perturbations in MLP with differentiable activation functions. This sensitivity function can be regarded as an ensemble average of deterministic sensitivity measures due to the perturbations of weights. Hence, this sensitivity function can be used as the criteria for selecting weights with the minimum sensitivity among possible sets of connection weights in MLP. For the verification of the validity of the proposed sensitivity function, computer simulations have been performed and through the simulations we find good agreement between the theoretical and simulation results.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2005년도 학술발표회 논문집
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• pp.521-528
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• 2005

In our previous study, we have developed a preliminary design procedure of MR dampers for controlling seismic response of building structures. In this paper, the effectiveness the proposed method is verified through the numerical analysis of the structures with various period and story number, and twenty earthquake loads are used for statistical assessment. The comparison between the proposed method and simplified sequential search algorithm indicates that the capacity, number and the placement of the MR damper which can achieve the given performance objective are reasonably determined using the proposed design procedure.

• International Journal of Advanced Culture Technology
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• 제5권3호
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• pp.40-45
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• 2017

This data mining technique was used to extract useful information from percutaneous coronary intervention data obtained from the US public data homepage. The experiment was performed by extracting data on the area, frequency of operation, and the number of deaths. It led us to finding of meaningful correlations, patterns, and trends using various algorithms, pattern techniques, and statistical techniques. In this paper, information is obtained through efficient decision tree and cluster analysis in predicting the incidence of percutaneous coronary intervention and mortality. In the cluster analysis, EM algorithm was used to evaluate the suitability of the algorithm for each situation based on performance tests and verification of results. In the cluster analysis, the experimental data were classified using the EM algorithm, and we evaluated which models are more effective in comparing functions. Using data mining technique, it was identified which areas had effective treatment techniques and which areas were vulnerable, and we can predict the frequency and mortality of percutaneous coronary intervention for heart disease.

• 한국의류산업학회지
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• 제10권2호
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• pp.220-227
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• 2008

The purpose of this study was to investigate the relationship between the image advertising of a college and the college image, and the behavior of choosing a college and a major. Data were collected from students of 4 colleges in Daegu. Convenienced sampling was performed, and 259 responses were used for analysis. In the statistical analysis, factor analysis and regression analysis were used for verification. The results were as following; The image advertising concept of a college constituted one factor, and the college image consist of the college's internal image factor and the external image factor. It shows that the image advertising of a college/the college image has a direct influence on the behavior of choosing a college and a major. Furthermore, through interaction with the college image, the image advertising also has an indirect influence.

• 한국소음진동공학회논문집
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• 제16권5호
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• pp.521-528
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• 2006

The vibration fatigue is suitable case of fatigue problem that system is exposed to the random or other irregular sources. Even some kinds of effort using power spectral density (PSD) and statistical concept was presented to cope with the intangible force signal, it is still lack of providing a reasonable solution when its exciting frequency is near or beyond of first eigenvalue. In this paper, energy approach method is presented to calculate a vibration induced fatigue damage in frequency domain. Since the corresponding damage become much larger than nominal case when the vibration is coupled with a mode shape of given structure, the new technique compensate the characteristics of structure with a measured frequency response function (FRF) between forcing acceleration and responding stress.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (2)
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• pp.529-531
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• 2002

생체인식 시스템은 개인의 물리적/행동적 특성을 측정하여 신원을 확인하기 위한 시스템이다. 이러한 시스템에서 사용되는 특징들은 잡음 등에 의해서 쉽게 영향을 받기 때문에 매우 많은 변형들이 존재하고, 따라서 변형된 특징들을 효과적으로 다루기 위해 다양한 기계학습 방법들이 사용되고 있다. 그런데, 기존의 자료주도적인 방법들을 특정 생체인식 시스템에 적용하기 위해서는 시스템에 등록할 각 사람들로부터 충분히 많은 데이터를 획득해야하는 어려움을 겪게 된다. 또한 시스템에 미등록된 사람의 데이터가 제시될 가능성 등, 무한한 수의 변형이 존재하는 문제점을 갖고 있다. 이러한 문제점들로 인해 데이터의 분포특성을 분석하고 예측하는 것이 어렵다. 생체인식 시스템의 이러한 고유의 문제점을 극복하기 위해서는 새로운 효율적인 식별 및 검증 방법을 필요하다. 따라서, 본 논문에서는 통계적 가설 검증 이론에 기초한 간단한 방법을 제안하고, 실세계 데이터에 대한 실험을 통해 제안한 방법의 가능성을 확인한다.

• Computers and Concrete
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• 제15권2호
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• pp.279-304
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• 2015

In this study, reliability analyses of steel fiber reinforced concrete (SFRC) corbels based on stochastic finite element were performed for the first time in literature. Prior to stochastic finite element analysis, an experimental database of 84 sfrc corbels was gathered from literature. These sfrc corbels were modeled by a special finite element program. Results of experimental studies and finite element analysis were compared and found to be very close to each other. Furthermore experimental crack patterns of corbel were compared with finite element crack patterns and were observed to be quite similar. After verification of the finite element models, stochastic finite element analyses were implemented by a specialized finite element module. As a result of stochastic finite element analysis, appropriate probability distribution functions (PDF's) were proposed. Finally, coefficient of variation, bias and strength reduction (resistance) factors were proposed for sfrc corbels as a consequence of stochastic based reliability analysis.

• 대한인간공학회지
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• 제25권3호
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• pp.61-66
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• 2006

Awkward work postures in workshop highly affect on work-related musculoskeletal disorders(WMSDs). Especially, in automobiles assembly process, these awkward work postures of workers may cause serious injury and illness. This study is to compare the performance among the evaluation tools which can measure the work-loads caused by the awkward work postures in automobiles assemble process. RULA, REBA and TVAL(Toyota Verification of Assembly Line) are used as the evaluation tools. The 85 jobs selected in the automobiles assembly process are applied to the three tools and their performances are analyzed after the evaluation of the work-load in each job. Through various measures of performance such as statistical test, DUNCAN test, regression test etc., the tendencies and characteristics among them are analyzed in detail.