• 한국음향학회:학술대회논문집
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• 한국음향학회 1994년도 FIFTH WESTERN PACIFIC REGIONAL ACOUSTICS CONFERENCE SEOUL KOREA
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• pp.698-703
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• 1994

In the actual sound environment, the random signal often shows a complex fluctuation pattern apart from a standard Gaussian distribution. In this study, an evaluation method for the sound environmnetal system is proposed in the generalized form applicable to the actual stochastic phenomena, by introducing two type information processing methods based on the regression model of expansion series type and the Fuzzy probability. The effectiveness of the proposed method are confirmed experimentally too by applying it to the observed data in the actual noise environment.

• 한국컴퓨터정보학회논문지
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• 제24권4호
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• pp.107-112
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• 2019

Failure testing is a test that verifies that the system is operating in accordance with failure response requirements. A typical failure test approaches the operating system by identifying and testing system problems caused by unexpected errors during the operational phase. In this paper, we study how to evaluate these Failure at the software development stage. Evaluate the probability of failure due to code changes through the complexity and duplication of the code, and evaluate the probability of failure due to exceptional situations with bugs and test coverage extracted from static analysis. This paper studies the possibility of failure based on the code quality of software development stage.

• Journal of the Korean Data and Information Science Society
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• 제14권2호
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• pp.209-216
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• 2003

Contingent valuation method (CVM) is a main evaluation method of nonmarket goods for which markets either do not exist at all or do exist only incompletely; an example is environmental good. A dichotomous choice approach, the most popular type of CVM in environmental economics, employs binary discrete choice models as statistical estimation models. In this paper, we propose a semiparametric dichotomous choice CVM method using local linear model of Fan and Gijbels (1996) in which probability distribution of error term is specified parametrically but latent structural function is specified nonparametrically. The computation procedures of the proposed method are illustrated with a simple design of simulations.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1998년도 가을 학술발표회 논문집
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• pp.217-224
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• 1998

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 춘계학술발표회
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• pp.233-234
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• 2005

• 해양환경안전학회지
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• 제3권1호
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• pp.33-49
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• 1997

One of the most important missons that are imposed on merchant ship at sea is to accomplish the safe transportation of cargo loaded. Recently, a study on the seakeeping performance has been carried out on the development of evaluation system related to the synthetic safety of a ship at sea. The seakeeping performance is the ship's ability sailing at, and executing its misson against adverse environmental factors successfully and safely. Until now, however, there has not been any method of quantitative evaluation on the dynamic safety of the ship's cargo loaded. In this regards, this paper has introduced the evaluation method of dynamic safety of the ship's cargo. In order to evaluate the dynamic safety of cargo, the vertical and lateral acceleration which causes the collapse, racking and local structure failure of cargo was adopted as the evaluation factors in the ship's motions. The response amplitude of ship's motions in regular waves is manipulated by NSM (New Strip Method) on a given 2,700 TEU full container vessel under the wind forces of 7, 8 and 9 Beaufort scale. Each response of ship's motions induced by NSM was applied to short-crested irregular waves for stochastic process on evaluation factors and then vertical and lateral acceleration of each cargo was compared with significant amplitude of each acceleration. A representative dangerous factor was determined by comparing permissible values of stacking and racking forces occurred typically to the vertical and transverse directions with the container strength required on ISO 1496 at the positions of forecastle, poop and ship's midship respectively. Through the occurrence probability of the determined factor by Rayleigh's probability density function, the dangerousness which limits loads on container's side wall as an evaluation was applied in judging of the danger of the ship's cargo loaded.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권11호
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• pp.2945-2965
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• 2023

The laser inertial measurement unit is a precision device widely used in rocket navigation system and other equipment, and its quality is directly related to navigation accuracy. In the quality evaluation of laser inertial measurement unit, there is inevitably uncertainty in the index input information. First, the input numerical information is in interval form. Second, the index input grade and the quality evaluation result grade are given according to different national standards. So, it is a key step to transform the interval information input by the index into the data form consistent with the evaluation result grade. In the case of uncertain input, this paper puts forward a method based on probability distribution to solve the problem of asymmetry between the reference grade given by the index and the evaluation result grade when evaluating the quality of laser inertial measurement unit. By mapping the numerical relationship between the designated reference level and the evaluation reference level of the index information under different distributions, the index evidence symmetrical with the evaluation reference level is given. After the uncertain input information is transformed into evidence of interval degree distribution by this method, the information fusion of interval degree distribution evidence is carried out by interval evidential reasoning algorithm, and the evaluation result is obtained by projection covariance matrix adaptive evolution strategy optimization. Taking a five-meter redundant laser inertial measurement unit as an example, the applicability and effectiveness of this method are verified.

• 대한교통학회지
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• 제25권4호
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• pp.109-121
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• 2007

자료결측의 심각성은 현실적으로 거의 대부분의 조사에서 발생한다. 비단 교통분야뿐만 아니라 인문사회 분야나 기상학, 생물학, 지구과학 등 모든 분야에서 인력식이든 기계식이든 조사 방식에 관계없이 발생한다. 교통자료 수집장비에서의 자료결측의 발생은 현실적으로 불가피한 현상으로 볼 수 있으며, 이와 같은 자료 수집과정에서 발생하는 결측을 신뢰성있게 추정하여 보정하였던 선행연구의 대부분은 교통량 자료의 결측값 보정시 통계적 검증없이 시간적인 임의의 종속성만 고려함으로서, 보정 성능이 떨어지는 단점을 노출하고 있다. 이들 연구에서 적용했던 기법들 또한, 교통량 자료가 가지고 있는 가장 큰 특징인 주기적 순환성(periodic circularity)이 제대로 반영되지 못함으로서 적용상 한계를 노출하고 있다. 본 연구는 현실적으로 거의 대부분의 조사과정에서 발생하는 자료결측의 심각성에 대한 인식을 토대로 대안으로 순환분포모형을 제안하였다. 이러한 자료결측 현상에 대응하고자 하였던 기존의 ad-hoc 또는 heuristic 보정 기법과 모형 기반 및 알고리즘 기반의 보정 기법에 관한 선행 연구의 고찰을 통하여 이들 기법들의 한계점을 확인하였다.

• 한국통신학회논문지
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• 제25권6A호
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• pp.794-801
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• 2000

본 논문에서는 디지털 통신시스템의 성능 평가를 위한 효율적인 새로운 성능 평가 기법을 제안하고, 디지털 위성방송 채널에서의 수행시간의 획기적인 개선 효과를 제시하고 있다. 제안 알고리즘에서는 기존의 Importance Sampling 기법이 안고 있는 근본적인 문제점을 해결하기 위하여, 센트랄 모우멘트 기법을 도입 사용하였다. 즉, 채널 부/복호기를 제외한 내부채널의 수신단에서 잡음이 혼합된 수신신호의 센트랄 오우멘트를 측정하여 수신신호의 확률적인 특성, 즉 누적확률분포함수를 구하고 이를 이용하여 채널 부/복호기의 성능을 평가함으로서, 채널 전체의 성능을 단시간에 완료할 수 있다. 또, 디지털 위성방송 채널을 이용한 시뮬레이션 결과를 토대로 시뮬레이션 시간 측면에서 알고리즘의 효율을 보이고 있으며, 부호화기를 포함한 비선형 위성 채널과 M-dimensional memory에서의 Importance Sampling 기법이 갖고 있는 문제점을 제안된 알고리즘을 이용해 해결했음을 보여주고 있다.

• 한국음향학회지
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• 제27권5호
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• pp.256-261
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• 2008

본 논문에서는 기존의 최소값 제어 재귀 평균기법(minima controlled recursive averaging, MCRA) 알고리즘에 조건 사후 최대 확률 (maximun a posteriori, MAP)을 적용한 음성향상을 제안한다. 기존의 MCRA는 파워스펙트럼에 평균을 취하고 각 서브밴드에서 음성 신호 존재 확률로 조절하는 스무딩 매개변수를 사용한다. 본 논문에서 제안된 알고리즘은 현재 프레임에 들어온 신호가 이전 프레임에서의 음성의 존재와 부재에 대한 조건을 부여해 주어 음성 신호 존재확률을 수정하여 음성향상에 적용한다. 제안된 음성 향상은 ITU-T P.862 perceptual evaluation of speech quality (PESQ)와 주관적 음질평가를 이용하여 평가하였고 기존의 MCRA 방법보다 향상된 결과를 나타내었다.