• Title/Summary/Keyword: local probability

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Evaluation of Irrigation Vulnerability Characteristic Curves in Agricultural Reservoir (농업용 저수지 관개 취약성 특성 곡선 산정)

  • Nam, Won-Ho;Kim, Taegon;Choi, Jin-Yong;Kim, Han-Joong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.54 no.6
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    • pp.39-44
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    • 2012
  • Water supply capacity and operational capability in agricultural reservoirs are expressed differently in the limited storage due to seasonal and local variation of precipitation. Since agricultural water supply and demand basically assumes the uncertainty of hydrological phenomena, it is necessary to improve probabilistic approach for potential risk assessment of water supply capacity in reservoir for enhanced operational storage management. Here, it was introduced the irrigation vulnerability characteristic curves to represent the water supply capacity corresponding to probability distribution of the water demand from the paddy field and water supply in agricultural reservoir. Irrigation vulnerability probability was formulated using reliability analysis method based on water supply and demand probability distribution. The lower duration of irrigation vulnerability probability defined as the time period requiring intensive water management, and it will be considered to assessment tools as a risk mitigated water supply planning in decision making with a limited reservoir storage.

Fusion of Local and Global Detectors for PHD Filter-Based Multi-Object Tracking (검출기 융합에 기반을 둔 확률가정밀도 (PHD) 필터를 적용한 다중 객체 추적 방법)

  • Yoon, Ju Hong;Hwang, Youngbae;Choi, Byeongho;Yoon, Kuk-Jin
    • Journal of Institute of Control, Robotics and Systems
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    • v.22 no.9
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    • pp.773-777
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    • 2016
  • In this paper, a novel multi-object tracking method to track an unknown number of objects is proposed. To handle multiple object states and uncertain observations efficiently, a probability hypothesis density (PHD) filter is adopted and modified. The PHD filter is capable of reducing false positives, managing object appearances and disappearances, and estimating the multiple object trajectories in a unified framework. Although the PHD filter is robust in cluttered environments, it is vulnerable to false negatives. For this reason, we propose to exploit local observations in an RFS of the observation model. Each local observation is generated by using an online trained object detector. The main purpose of the local observation is to deal with false negatives in the PHD filtering procedure. The experimental results demonstrated that the proposed method robustly tracked multiple objects under practical situations.

Fingerprint Image Quality Assessment for On-line Fingerprint Recognition (온라인 지문 인식 시스템을 위한 지문 품질 측정)

  • Lee, Sang-Hoon
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.2
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    • pp.77-85
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    • 2010
  • Fingerprint image quality checking is one of the most important issues in on-line fingerprint recognition because the recognition performance is largely affected by the quality of fingerprint images. In the past, many related fingerprint quality checking methods have typically considered the local quality of fingerprint. However, It is necessary to estimate the global quality of fingerprint to judge whether the fingerprint can be used or not in on-line recognition systems. Therefore, in this paper, we propose both local and global-based methods to calculate the fingerprint quality. Local fingerprint quality checking algorithm considers both the condition of the input fingerprints and orientation estimation errors. The 2D gradients of the fingerprint images were first separated into two sets of 1D gradients. Then,the shapes of the PDFs(Probability Density Functions) of these gradients were measured in order to determine fingerprint quality. And global fingerprint quality checking method uses neural network to estimate the global fingerprint quality based on local quality values. We also analyze the matching performance using FVC2002 database. Experimental results showed that proposed quality check method has better matching performance than NFIQ(NIST Fingerprint Image Quality) method.

Semiparametric Evaluation of Environmental Goods: Local Linear Model Approach

  • Jeong, Ki-Ho
    • Journal of the Korean Data and Information Science Society
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    • v.14 no.2
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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.

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Estimation of Reward Probability in the Fronto-parietal Functional Network: An fMRI Study

  • Shin, Yeonsoon;Kim, Hye-young;Min, Seokyoung;Han, Sanghoon
    • Science of Emotion and Sensibility
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    • v.20 no.4
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    • pp.101-112
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    • 2017
  • We investigated the neural representation of reward probability recognition and its neural connectivity with other regions of the brain. Using functional magnetic resonance imaging (fMRI), we used a simple guessing task with different probabilities of obtaining rewards across trials to assay local and global regions processing reward probability. The results of whole brain analysis demonstrated that lateral prefrontal cortex, inferior parietal lobe, and postcentral gyrus were activated during probability-based decision making. Specifically, the higher the expected value was, the more these regions were activated. Fronto-parietal connectivity, comprising inferior parietal regions and right lateral prefrontal cortex, conjointly engaged during high reward probability recognition compared to low reward condition, regardless of whether the reward information was extrinsically presented. Finally, the result of a regression analysis identified that cortico-subcortical connectivity was strengthened during the high reward anticipation for the subjects with higher cognitive impulsivity. Our findings demonstrate that interregional functional involvement is involved in valuation based on reward probability and that personality trait such as cognitive impulsivity plays a role in modulating the connectivity among different brain regions.

A Case Study on the Seismic Hazard Classification of Domestic Drinking Water Earthfill Dams Using Zero Seismic Failure Probability Curve (지진파괴확률 영곡선 활용 국내 식수전용 흙댐의 지진 위험도 분류 사례 연구)

  • Ha, Ik-soo
    • Journal of the Earthquake Engineering Society of Korea
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    • v.26 no.4
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    • pp.173-180
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    • 2022
  • Most of the drinking water dams managed by the local governments in Korea are earthfill dams, and these dams have almost no geotechnical property information necessary for seismic performance evaluation. Nevertheless, in the rough planning stage for improving seismic safety for these dams, it is necessary to classify their relative seismic hazard against earthquakes and conduct an additional ground investigation. The zero seismic failure probability curve is a curve suggested in this study in which the probability of failure due to an earthquake becomes '0' regardless of the geotechnical properties of the earthfill dam. By examining the method and procedure for calculating failure probability due to an earthquake suggested in previous researches, the zero seismic failure probability curves for an earthquake in 1,000-year and 2,400-year return periods in Korea were presented in the form of a hyperbola on the plane of the dam height versus freeboard ratio (ratio of freeboard to dam height), respectively. The distribution characteristics of the dam height and the freeboard ratio of 81 Korean earthfill dams were presented. The two proposed zero seismic failure probability curves are shown on the plane of the dam height versus freeboard ratio, and the relative seismic hazard of 81 dams can be classified into three groups using these curves as boundaries. This study presented the method of classifying the relative seismic hazard and the classification result.

Routing Algorithm of VANET for an Efficient Path Management in Urban Intersections (도심 교차로에서 효율적 경로 관리를 위한 자동차 통신용 라우팅 알고리즘)

  • Cho, Sunghyun;Kim, Seokwoo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.12
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    • pp.1054-1060
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    • 2013
  • This paper proposes a vehicle ad-hoc network (VANET) routing algorithm to reduce the probability of routing path discontinuity in urban intersections. In urban intersections, the vehicles may frequently change their moving directions. It can cause the disconnection of routing path and the increase of a packet transmission delay. In order to resolve this problem, the proposed routing algorithm exploits the information of moving directions in urban intersections. In this way, the proposed algorithm can reduce the probability of the local maximum which causes the increase of the number of routing hops and packet transmission delay. Simulation results show that the proposed algorithm can reduce the local maximum probability by 10% and increase the successful packet transmission ratio by 5% compared to the conventional VANET routing algorithms.

A Service Life Prediction for Joint and Cracked Concrete Exposed to Carbonation Based on Stochastic Approach (신뢰성 해석을 통한 탄산화에 노출된 타설이음부 및 균열부 콘크리트의 내구수명 평가)

  • Kwon, Seung-Jun;Park, Sang-Sun;Lee, Sang-Min
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.11a
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    • pp.597-600
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    • 2006
  • In this study, field survey of carbonation for RC column in city is carried out and carbonation behavior in sound, joint, and cracked concrete is also analyzed. Futhermore, probability of durability failure with time is calculated through considering probability variables such as concrete cover depth and carbonation depth which are obtained from field survey. The probability of durability failure in cracked concrete with considering crack width and time is also calculated and service life is predicted based on intended failure probability in domestic specification. Through this study, it is known that service life in a RC column is evaluated differently for local conditions and each service life is rapidly decreased with decrease in cover depth and increase in crack width.

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Mixing matrix estimation method for dual-channel time-frequency overlapped signals based on interval probability

  • Liu, Zhipeng;Li, Lichun;Zheng, Ziru
    • ETRI Journal
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    • v.41 no.5
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    • pp.658-669
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    • 2019
  • For dual-channel time-frequency (TF) overlapped signals with low sparsity in underdetermined blind source separation (UBSS), this paper proposes an effective method based on interval probability to estimate and expand the types of mixing matrices. First, the detection of TF single-source points (TF-SSP) is used to improve the TF sparsity of each source. For more distinguishability, as the ratios of the coefficients from different columns of the mixing matrix are close, a local peak-detection mechanism based on interval probability (LPIP) is proposed. LPIP utilizes uniform subintervals to optimize and classify the TF coefficient ratios of the detected TF-SSP effectively in the case of a high level of TF overlap among sources and reduces the TF interference points and redundant signal features greatly to enhance the estimation accuracy. The simulation results show that under both noiseless and noisy cases, the proposed method performs better than the selected mainstream traditional methods, has good robustness, and has low algorithm complexity.

Distributed Resource Allocation in Multimedia Ad Hoc Local Area Networks Based on OFDM-CDMA (OFDM-CDMA 기반 멀티미디어 무선 Ad Hoc LAN에서의 분산적 자원 할당 방식)

  • Yang, Hyun-ho;Jeon, Hee-jeong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.7
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    • pp.1250-1256
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    • 2001
  • A resource management scheme for ad hoc wireless local area networks (AWLAN's) is presented. This scheme combines distributed resource management scheme and orthogonal frequency division multiplexing-code division multiple access(OFDM-CDMA) technique to support multimedia services with QoS guarantees. The performance evaluation has done in terms of blocking rates and QoS loss probability.

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