• Title/Summary/Keyword: Stochastic media

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Estimation of Motion-Blur Parameters Based on a Stochastic Peak Trace Algorithm (통계적 극점 자취 알고리즘에 기초한 움직임 열화 영상의 파라메터 추출)

  • 최병철;홍훈섭;강문기
    • Journal of Broadcast Engineering
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    • v.5 no.2
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    • pp.281-289
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    • 2000
  • While acquiring images, the relative motion between the imaging device and the object scene seriously damages the image quality. This phenomenon is called motion blur. The peak-trace approach, which is our recent previous work, identifies important parameters to characterize the point spread function (PSF) of the blur, given only the blurred image itself. With the peak-trace approach the direction of the motion blur can be extracted regardless of the noise corruption and does not need much Processing time. In this paper stochastic peak-trace approaches are introduced. The erroneous data can be selected through the ML classification, and can be made small through weighting. Therefore the distortion of the direction in the low frequency region can be prevented. Using the linear prediction method, the irregular data are prohibited from being selected as the peak point. The detection of the second peak using the proposed moving average least mean (MALM) method is used in the Identification of the motion extent. The MALM method itself includes a noise removal process, so it is possible to extract the parameters even an environment of heavy noise. In the experiment, we could efficiently restore the degraded image using the information obtained by the proposed algorithm.

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Variations of Longitudinal Moments for a Contaminant Transport in Physically and Chemically Heterogeneous Media (물리.화학적 불균질 특성을 지닌 매질 내 오염운 이동시 보이는 종적률 변화)

  • Seo, Byong-Min;Jung, Joon-Oh;Kim, Young-Woo;Hwang, Seung-Min
    • The Journal of Engineering Geology
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    • v.19 no.1
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    • pp.81-88
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    • 2009
  • Two dimensional Monte-Carlo simulations of a non-reactive solute plume in isotropic porous media which are physically and chemically heterogeneous are conducted to determine the variations of moment. Retardation factors of 1, 2 and 5 are given to ascertain how the second moments are changed as adsorption increased. Retarded longitudinal second spatial moment, ${Z_{11}}^{'R}(t',l')$, increased during the transport process and as the dimensionless lengths of line plume source, $l_2'$, increased. ${Z_{11}}^{'R}(t',l')$ decreased as the retardation factors increased, and the simulated moments fit well to the first-order analytical results. Retarded longitudinal plume centroid variance, ${Z_{11}}^{'R}(t',l')$, decreased as the dimensionless lengths of line plume source, $l_2'$, increased and as the retardation factor increased. The result indicates that the uncertainty about the plume center decreased, and the ergodic condition for the second spatial moments is far from reaching. Simulated longitudinal one particle displacement covariance, ${Z_{11}}^{'R}(t')$, well consistent with the first-order analytical results for the three degrees of retardation factors of 1, 2 and 5 respectively. It is, consequently, concluded that the retarded longitudinal second moments could be produced by stochastic simulation, and that the first-order analytical results definitely provides very close values of the longitudinal retarded moments.

A Nuclide Transport Model in the Fractured Rock Medium Using a Continuous Time Markov Process (연속시간 마코프 프로세스를 이용한 균열암반매질에서의 핵종이동 모델)

  • Lee, Y.M.;Kang, C.H.;Hahn, P.S.;Park, H.H.;Lee, K.J.
    • Nuclear Engineering and Technology
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    • v.25 no.4
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    • pp.529-538
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    • 1993
  • A stochastic way using continuous time Markov process is presented to model the one-dimensional nuclide transport in fractured rock matrix as an extended study for previous work [1]. A nuclide migration model by the continuous time Markov process for single planar fractured rock matrix, which is considered as a transient system where a process by which the nuclide is diffused into the rock matrix from the fracture may be no more time homogeneous, is compared with a conventional deterministic analytical solution. The primary desired quantities from a stochastic model are the expected values and variance of the state variables as a function of time. The time-dependent probability distributions of nuclides are presented for each discretized compartment of the medium given intensities of transition. Since this model is discrete in medium space, parameters which affect nuclide transport could be easily incorporated for such heterogeneous media as the fractured rock matrix and the layered porous media. Even though the model developed in this study was shown to be sensitive to the number of discretized compartment showing numerical dispersion as the number of compartments are decreased, with small compensating of dispersion coefficient, the model agrees well to analytical solution.

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BETTER UNDERSTANDING OF THE BIOLOGICAL EFFECTS OF RADIATION BY MICROSCOPIC APPROACHES

  • Kim, Eun-Hee
    • Nuclear Engineering and Technology
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    • v.40 no.7
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    • pp.551-560
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    • 2008
  • Radiation has stochastic aspects in its generation, its choice of interaction mode during traveling in media, and its impact on living bodies. In certain circumstances, like in high dose environments resulting from low-LET radiation, the variance in its impact on a target volume is negligible. On the contrary, in low dose environments, especially when they are attributed to high-LET radiation, the impact on the target carries with it a large variance. This variation is more significant for smaller target volumes. Microdosimetric techniques, which have been developed to estimate the distribution of radiation energy deposited to cellular and subcellular-sized targets, contrast with macrodosimetric techniques which count only the average value. Since cells and DNA compounds are the critical targets in human bodies, microdosimetry, or dose estimation by microscopic approach, helps one better analyze the biological effects of radiation on the human body. By utilizing microbeam systems designed for individual cell irradiation, scientists have discovered that human cells exhibit radiosensitive reactions without being hit themselves (bystander effect). During the past 10 or more years, a new therapeutic protocol using discontinuous multiple micro-slit beams has been investigated for its clinical application. It has been suggested that the beneficial bystander effect is the essence of this protocol.

Stochastic Non-linear Hashing for Near-Duplicate Video Retrieval using Deep Feature applicable to Large-scale Datasets

  • Byun, Sung-Woo;Lee, Seok-Pil
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.8
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    • pp.4300-4314
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    • 2019
  • With the development of video-related applications, media content has increased dramatically through applications. There is a substantial amount of near-duplicate videos (NDVs) among Internet videos, thus NDVR is important for eliminating near-duplicates from web video searches. This paper proposes a novel NDVR system that supports large-scale retrieval and contributes to the efficient and accurate retrieval performance. For this, we extracted keyframes from each video at regular intervals and then extracted both commonly used features (LBP and HSV) and new image features from each keyframe. A recent study introduced a new image feature that can provide more robust information than existing features even if there are geometric changes to and complex editing of images. We convert a vector set that consists of the extracted features to binary code through a set of hash functions so that the similarity comparison can be more efficient as similar videos are more likely to map into the same buckets. Lastly, we calculate similarity to search for NDVs; we examine the effectiveness of the NDVR system and compare this against previous NDVR systems using the public video collections CC_WEB_VIDEO. The proposed NDVR system's performance is very promising compared to previous NDVR systems.

A Characterization of Oil Sand Reservoir and Selections of Optimal SAGD Locations Based on Stochastic Geostatistical Predictions (지구통계 기법을 이용한 오일샌드 저류층 해석 및 스팀주입중력법을 이용한 비투멘 회수 적지 선정 사전 연구)

  • Jeong, Jina;Park, Eungyu
    • Economic and Environmental Geology
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    • v.46 no.4
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    • pp.313-327
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    • 2013
  • In the study, three-dimensional geostatistical simulations on McMurray Formation which is the largest oil sand reservoir in Athabasca area, Canada were performed, and the optimal site for steam assisted gravity drainage (SAGD) was selected based on the predictions. In the selection, the factors related to the vertical extendibility of steam chamber were considered as the criteria for an optimal site. For the predictions, 110 borehole data acquired from the study area were analyzed in the Markovian transition probability (TP) framework and three-dimensional distributions of the composing media were predicted stochastically through an existing TP based geostatistical model. The potential of a specific medium at a position within the prediction domain was estimated from the ensemble probability based on the multiple realizations. From the ensemble map, the cumulative thickness of the permeable media (i.e. Breccia and Sand) was analyzed and the locations with the highest potential for SAGD applications were delineated. As a supportive criterion for an optimal SAGD site, mean vertical extension of a unit permeable media was also delineated through transition rate based computations. The mean vertical extension of a permeable media show rough agreement with the cumulative thickness in their general distribution. However, the distributions show distinctive disagreement at a few locations where the cumulative thickness was higher due to highly alternating juxtaposition of the permeable and the less permeable media. This observation implies that the cumulative thickness alone may not be a sufficient criterion for an optimal SAGD site and the mean vertical extension of the permeable media needs to be jointly considered for the sound selections.

Performance Improvement of Freight Logistics Hub Selection in Thailand by Coordinated Simulation and AHP

  • Wanitwattanakosol, Jirapat;Holimchayachotikul, Pongsak;Nimsrikul, Phatchari;Sopadang, Apichat
    • Industrial Engineering and Management Systems
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    • v.9 no.2
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    • pp.88-96
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    • 2010
  • This paper presents a two-phase quantitative framework to aid the decision making process for effective selection of an efficient freight logistics hub from 8 alternatives in Thailand on the North-South economic corridor. Phase 1 employs both multiple regression and Pearson Feature selection to find the important criteria, as defined by logistics hub score, and to reduce number of criteria by eliminating the less important criteria. The result of Pearson Feature selection indicated that only 5 of 15 criteria affected the logistics hub score. Moreover, Genetic Algorithm (GA) was constructed from original 15 criteria data set to find the relationship between logistics criteria and freight logistics hub score. As a result, the statistical tools are provided the same 5 important criteria, affecting logistics hub score from GA, and data mining tool. Phase 2 performs the fuzzy stochastic AHP analysis with the five important criteria. This approach could help to gain insight into how the imprecision in judgment ratios may affect their alternatives toward the best solution and how the best alternative may be identified with certain confidence. The main objective of the paper is to find the best alternative for selecting freight logistics hub under proper criteria. The experimental results show that by using this approach, Chiang Mai province is the best place with the confidence interval 95%.

The Phenomenological Comparison between Results from Single-hole and Cross-hole Hydraulic Test (균열암반 매질 내 단공 및 공간 간섭 시험에 대한 현상적 비교)

  • Kim, Tae-Hee;Kim, Kue-Young;Oh, Jun-Ho;Hwang, Se-Ho
    • Journal of Soil and Groundwater Environment
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    • v.12 no.5
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    • pp.39-53
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    • 2007
  • Generally, fractured medium can be described with some key parameters, such as hydraulic conductivities or random field of hydraulic conductivities (continuum model), spatial and statistical distribution of permeable fractures (discrete fracture network model). Investigating the practical applicability of the well-known conceptual models for the description of groundwater flow in fractured media, various types of hydraulic tests were applied to studies on the highly fractured media in Geumsan, Korea. Results from single-hole packer test show that the horizontal hydraulic conductivities in the permeable media are between $7.67{\times}10^{-10}{\sim}3.16{\times}10^{-6}$ m/sec, with $7.70{\times}10^{-7}$ m/sec arithmetic mean and $2.16{\times}10^{-7}$ m/sec geometric mean. Total number of test interval is 110 at 8 holes. The number of completely impermeable interval is 9, and the low permeable interval - below $1.0{\times}10^{-8}$ m/sec is 14. In other words, most of test intervals are permeable. The vertical distribution of hydraulic conductivities shows apparently the good correlation with the results of flowmeter test. But the results from the cross-hole test show some different features. The results from the cross-hole test are highly related to the connectivity and/or the binary properties of fractured media; permeable and impermeable. From the viewpoint of the connection, the application of the general stochastic approach with a single continuum model may not be appropriate even in the moderately or highly permeable fractured medium. Then, further studies on the investigation method and the analysis procedures should be required for the reasonable and practical design of the conceptual model, with which the binary properties, including permeable/impermeable features, can be described.

Density Estimation Technique for Effective Representation of Light In-scattering (빛의 내부산란의 효과적인 표현을 위한 밀도 추정기법)

  • Min, Seung-Ki;Ihm, In-Sung
    • Journal of the Korea Computer Graphics Society
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    • v.16 no.1
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    • pp.9-20
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    • 2010
  • In order to visualize participating media in 3D space, they usually calculate the incoming radiance by subdividing the ray path into small subintervals, and accumulating their respective light energy due to direct illumination, scattering, absorption, and emission. Among these light phenomena, scattering behaves in very complicated manner in 3D space, often requiring a great deal of simulation efforts. To effectively simulate the light scattering effect, several approximation techniques have been proposed. Volume photon mapping takes a simple approach where the light scattering phenomenon is represented in volume photon map through a stochastic simulation, and the stored information is explored in the rendering stage. While effective, this method has a problem that the number of necessary photons increases very fast when a higher variance reduction is needed. In an attempt to resolve such problem, we propose a different approach for rendering particle-based volume data where kernel smoothing, one of several density estimation methods, is explored to represent and reconstruct the light in-scattering effect. The effectiveness of the presented technique is demonstrated with several examples of volume data.

Estimation of Motion-Blur Parameters Based on Stochastic Peak-Trace Algorithm (확률적 극점자취방법을 통한 움직임열화가 발생한 영상에서의 파라메터 추출)

  • 최병철;강문기
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1999.11b
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    • pp.99-104
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    • 1999
  • 영상을 획득하는 과정에 있어, 영상획득 장치 또는 피사체의 흔들림으로 인해 발생되는 움직임 열화(motion-blur)현상은 영상의 선명도를 크게 떨어뜨리는 주된 원인이 된다. 손상된 영상은 그 영상자체로부터 움직임의 각도와 길이를 추출 함으로서 복원될 수 있다. 본 논문에서는 움직임 열화의 각도와 길이를 추정하기 위한 방법 중, 본 저자가 제안 했던 극점자취방법에, 확률적인 개념을 적용한 새로운 확률적 극점자취 방법을 소개한다. 기존의 방법은 신호지배영역이 올바로 지정되지 않았을 경우, 오차를 수반하기도 한다. 이러한 문제를 해결 하기 위해, 본 연구에서는 maximum likelihood(ML) 분류방법을 이용해 적절하지 않은 극점자취점의 영향을 선택적으로 작게 하여, 신호지배 영역의 설정 없이, 저주파 영역에서의 올른 극점자취의 검출이 가능하도록 하였다. 또한, Auto-regressive(Ah) 모델을 이용한 선형예측방법을 통해 극점 검출과정에서 불규칙하게 발생하는 특이점들이 극점으로 검출되지 못하도록 하여, 정밀한 움직임 방향의 추정이 가능하게 하였다. 또한, 움직임 길이의 검출에 있어서는, 노이즈에 의해 영향을 무시할 수 없는 기존의 영점교차점 방법을 보완한, 새로운 이동평균최소(MALM)법을 정의하였다 이 방법은 움직임 열화가 발생한 영상의 주파수 영역단면 패턴을 이용한 것으로서, 2차원적인 sinc함수를 1차원적인 표현으로 바꾸어주는 이동평균함수를 사용하여, 쉽게 부극점(sub-peak point)을 찾을 수 있도록 한다 부극점 또한 노이즈에 의한 영향을 받지 않고, 이동평균최소법 자체에 노이즈를 제거하는 과정에 포함되어있으므로. 이 방법을 사용하게 되면, 심한 노이즈 환경에서도 적절한 움직임의 길이 값을검출할 수 있다. 이렇게 얻어진 길이와 방향의 파라메터를 이용하여, 실제 실험에 사용된 손상되어진 영상을 효과적으로 복원할 수 있었다.>$\bigcirc$ 펄라이트 : 합섬A(비스코스+레이온)급액천의 유입은 소(1$\times$60cm)에서 21.8ml, 중(2$\times$60cm) 33.5ml, 대(3$\times$60cm) 43.4ml가 통과되었고 합섬(폴리에스텔)에서는 19.0~30.7ml로서 급액천의 규격에 따라 통과되는 차이가 있었다. 배지가 규격화되어 있어 급액천의 규격별로 일정하게 유입되었으며 급액천의 재질이 유입에 영향을 미친 것으로 사료되었다. (2) 급액관과 베드상과의 높이에 따른 유출양 : 급액과 베드상과의 낙차가 클수록 유출이 증가함을 알수 있었으나 합섬C(인견)실험구에서는 낙차가 유출에 영향을 미치지 않았다. (4) 급액된 양액의 EC 및 pH조사 : 급액된 양액의 EC 및 pH에 전혀 변화가 없어 재배 적응에 문제가 없을것으로 사료되었다.이가 가장 이상적인 것으로 생각된다.세포수에 대한 내부세포괴세포(ICM/total cells)가 20~40% 범주에 드는 비율은 처리구가 대조구보다 낮은 결과를 나타냈다. 결론적으로 돼지난포란을 이용하여 체외성숙을 유기할 때 효과적인 cysteamine의 농도는 50$\mu$M이 적당하며, 초기배발달을 유기할 때의 효과적인 cysteamine의 농도는 25~50$\mu$M인 것으로 판단된다.N)A(N)/N을 제시하였다(A(N)=N에 대한 A값). 위의 실험식을 사용하여 헝가리산 Zempleni 시료(15%$S_{XRD}$)의 기본입자분포로부터 %$S_{XRD}$를 계산한 결과, 16%$S_{XRD}$의 결과값을 얻을 수 있었다. 따라서, 본 연구에서 도출한 관계식들이 유효함을 확인할 수 있었다.계식들이 유효함을 확인할 수 있었다.할 때 약간의 증가를 나타냈다.". And

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