• 응용통계연구
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• 제26권4호
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• pp.623-634
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• 2013

본 연구에서는 교통 분석존(서울시 행정동) 단위별로 대중교통 수단(버스, 도시철도)선택에 있어서 공간 상관성이 존재하는지 여부를 대중교통카드 자료를 기반으로 제시한다. 분석결과 버스를 탑승한 비율이 높은 지역들이 서로 이웃하여 그룹을 형성하고 있으며, 이들 지역은 도시철도 역사의 수가 버스 정류장에 비해 매우 적기 때문인 것으로 분석되었다. 버스에 탑승한 비율이 비슷한 그룹 간에는 공간 상관성이 존재하는 것으로 통계분석결과 나타났으며, 이러한 공간상관성은 향후 대중교통 수단선택 모형 구축에 고려할 수 있을 것으로 판단된다. 대중교퉁 수단선택에 있어 공간상관성의 존재는 대중교통 운영기관이 향후 대중교통카드를 기반으로 대중교통 노선계획, 운영계획을 수립함에 있어 중요한 정보가 될 것으로 기대된다.

• Journal of Advanced Marine Engineering and Technology
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• 제25권5호
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• pp.1058-1064
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• 2001

In this paper, the development of probability distribution estimation program for fatigue crack growth lives was summarize. The probability distribution estimation program of life was developed to increase the reliability of life estimation. In this study, it is considered that the cause of scatter in fatigue crack growth data is due to material inhomogeneity. The material resistance to fatigue crack growth is modelled as a spatial stochastic process, which varies randomly along the crack path. We developed the GUI program to estimate the probability distribution and reliability using the non-Gaussian stochastic process method. This program can be used for the reliability assessment.

• 한국수자원학회논문집
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• 제32권1호
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• pp.3-13
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• 1999

본 연구에서는 공간 분포의 해석을 위하여 일반적으로 사용되어 오던 Thiessen 또는 Kriging 법들을 대체할 수 있는 새로운 모형인 SANN(Spatial-Analysis Neural-Network)을 소개한다. 이 모델은 신경망 기법을 이용한 비매개 변수법의 일종으로 미측정 기점의 평균값 뿐만 아니라 분산, 왜도 등의 고차 통계치를 제공하여 준다. 또한 어떤 기점에서의 공간변수의 값이 그 심각도에 따른 미리 지정된 여러 분류들 중 각각의 분류에 속할 확률값과 전체 공간을 각 분류에 따라 가장 최적하게 분류경제(class boundary)를 선정하여줄 수 있는 Bayesian 계급분류기(Classifier)를 제공하는 의사결정(decision-making) 역할도 수행할 수 있다. 본 연구에서는 제안된 SANN모형의 외삽기(interpolator)를 사용하여 관측 기점의 연평균 강우량을 대상 유역 전체의 공간적으로 분포시키고 또한 각 지점의 예측 오류를 산정하며, Bayesian 분류기를 사용하여 대상유역을 가장 적절하게 건조, 보통, 습윤 지역으로 분류하는 방법을 제시하여 본다. 본 연구에서는 39개 강우 계측 지점을 이용하여 우리나라의 연평균 강우의 공간 해석에 응용하여 본다. 결과적으로 연평균 강우량의 공간 분포, 표준편차, 그리고 확률도를 얻었다. 더불어 우리나라 전역을 건조, 보통, 습윤 지역으로 분류하여 보았다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2011년도 춘계학술대회
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• pp.539-542
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• 2011

본 논문에서는 무선 통신 시스템의 시변 공간 상관 채널 (time-varying and spatially correlated channel) 환경에서 전송 시공간 부호 및 단순 선형 복조 처리 방식(transmit space-time code and simple linear decoding processing)으로 구성된 $2{\times}1$ Alamouti scheme의 성능을 분석한다. Alamouti 구조의 closed-form 확률밀도함수 (probability density function, PDF), 출력 신호 대 잡음 비(output signal-to-noise ratio, SNR) 및 오수신 확률 (outage probability)을 시간영역에서의 상관관계가 없음을 가정하고 공간 상관 계수(spatial correlation coefficient)의 함수로 유도한다. 이로써 채널 환경이 시변 공간 상관 (time-varying and spatially correlated)된 경우, Alamouti 구조의 성능은 상당히 열화 됨을 확인할 수 있다.

• 한국농공학회논문집
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• 제55권3호
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• pp.105-111
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• 2013

Probability distribution of microbes in wastewater is a crucial factor to be determined for microbial risk assessment associated with its reuse. The objective of this study was to investigate probability distribution of an indicator microorganism in wastewater. Daily total coliform counts measured from nationwide wastewater treatment plants in 2010 by the Ministry of Environment were used for statistical analysis. Basic statistics and probability distributions were estimated in the three different spatial scales using the MS Excel software and FARD2006 model. Overall, wastewater from manure and livestock treatment plants demonstrated greater median coliform counts than from sewage and village treatment plants. Generalized logistic (GLO) and 2-parameter Weibull (WBU2) appeared to be the two probability distributions that fitted best for total coliform numbers in wastewater. The study results of microbial statistics and probability distributions would provide useful data for quantitative assessment of microbial risk from agricultural wastewater reuse.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.314-318
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• 2001

The analysis of the spatial extent of flood inundation is important for flood mitigation. Geographic Information System (GIS) has advantage of analyzing spatial distributed data. Hydrologic Engineering Center's River Analsysis System(HEC-RAS) with HEC-GeoRAS was used to analyze flood inundation. HEC-GeoRAS, which is an ArcView GIS extension designed to process geospatial data for HEC-RAS, is a useful tool for storing, managing, analyzing, and displaying spatially distributed data. Rational formula and 24-hr duration probability precipitation data of Suwon meteorological station were used to estimate the flood runoff. And water profiles were calculated using the HEC-RAS model with HEC-GeoRAS. The flooded region is 8.24ha when 50-yr probability precipitation was applied and 8.8ha when 100-yr was applied to Bahlan study watershed which is located in Whasung county, Kyunggi province, having an area of $29.79km^{2}$.

• 한국GIS학회:학술대회논문집
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• 한국GIS학회 2003년도 공동 춘계학술대회 논문집
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• pp.71-76
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• 2003

The purpose of this study is the development, application and assessment of probability and artificial neural network methods for assessing landslide susceptibility in a chosen study area. As the basic analysis tool, a Geographic Information System (GIS) was used for spatial data management. A probability method was used for calculating the rating of the relative importance of each factor class to landslide occurrence, For calculating the weight of the relative importance of each factor to landslide occurrence, an artificial neural network method was developed. Using these methods, the landslide susceptibility index was calculated using the rating and weight, and a landslide susceptibility map was produced using the index. The results of the landslide susceptibility analysis, with and without weights, were confirmed from comparison with the landslide location data. The comparison result with weighting was better than the results without weighting. The calculated weight and rating can be used to landslide susceptibility mapping.

• 수산해양기술연구
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• 제29권2호
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• pp.152-161
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• 1993

This paper deals with the effect of spatial distribution of material properties on its statistical characteristics and numerical estimation method of reliability of fatigue sensitive structures with respect to the fatigue crack growth. A method is proposed to determine experimentally the probability distribution functions of material parameters of Paris law. da/dN=C(ΔK/K sub(0) ) super(m), using stress intensity factor controlled fatigue tests. The result with a high tensile strength steel shows that the distribution of the parameter m is approximately normal and that of 1/C, is a 3-parameter Weibull. The main result obtained are : (1) The theoretical autocorrelation of the resistance, 1/C, to fatigue crack growth are almost same for different lengths. (2) The variance decreases with the increasing a averaging length. When spatial correlation length is very small. the variane decreases significantly were the averaging length. (3) The probability distribution of load cycles or the number for a crack to reach a certain length can be estimated using these functions by simulation of non-Gaussian(expecially Weibull) Stochastic Process.

• 대한원격탐사학회지
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• 제1권1호
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• pp.53-61
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• 1985

The purpose of the study is to establish models of land use prediction system for development and management of land resources using remotely sensed data as well as ancillary data in the context of multi-disciplinary approach in the application to CheJoo Island. The model adopts multi-date processing techniques and is a spatial/temporal land-use projection strategy emerged as a synthesis of the probability transition model and the discriminant-annlysis model. A discriminant model is applied to all pixels in CheJoo landscape plane to predict the most likely change in land use. The probability transition model provides the number of these pixels that will convert to different land use in a gives future time increment. The synthetic model predicts the future change in land use and its volume of pixels in the landscape plane.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.857-864
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• 2006

Due to the difficulties in numerical generation of random fields that satisfy not only the probabilistic distribution but the spectral characteristics as well. it is relatively hard to find an exact response variability of a structural response with a specific random field which has its features in the spatial and spectral domains. In this study. focusing on the fact that the random field assumes a constant over the domain under consideration when the correlation distance tends to infinity, a semi-theoretical solution of response variability is proposed for in-plane and plate bending structures. In this procedure, the probability density function is used directly resulting in a semi-exact solution for the random field in the state of random variable. It is particularly noteworthy that the proposed methodology provides response variability for virtually any type of probability density functions.