• Title/Summary/Keyword: Dempster-Shafer 이론

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A study on classification accuracy improvements using orthogonal summation of posterior probabilities (사후확률 결합에 의한 분류정확도 향상에 관한 연구)

  • 정재준
    • Spatial Information Research
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    • v.12 no.1
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    • pp.111-125
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    • 2004
  • Improvements of classification accuracy are main issues in satellite image classification. Considering the facts that multiple images in the same area are available, there are needs on researches aiming improvements of classification accuracy using multiple data sets. In this study, orthogonal summation method of Dempster-Shafer theory (theory of evidence) is proposed as a multiple imagery classification method and posterior probabilities and classification uncertainty are used in calculation process. Accuracies of the proposed method are higher than conventional classification methods, maximum likelihood classification(MLC) of each data and MLC of merged data sets, which can be certified through statistical tests of mean difference.

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A Computational Model of Trust and Its Applications in Internet Transactions (인터넷 거래에서 신뢰도의 계산적 모델 및 적용)

  • Noh, Sang-Uk
    • Journal of Internet Computing and Services
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    • v.8 no.4
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    • pp.137-147
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    • 2007
  • As Web-based online communities are rapidly growing, the agents in social groups need to know their measurable belief of trust for safe andsuccessful interactions. In this paper, we propose a computational model of trust resulting from available feedbacks in online communities. The notion of trust can be defined as an aggregation of consensus given a set of past interactions. The averagetrust of an agent further represents the center of gravity of the distribution of its trustworthiness and untrustworthiness. And then, we precisely describe the relationship between reputation, trust, and averagetrust through a concrete example of their computations. We apply our trust model to online internet settings in order to show how trust mechanisms are involved in a rational decision-making of the agents.

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A Novel Clustering Method with Time Interval for Context Inference based on the Multi-sensor Data Fusion (다중센서 데이터융합 기반 상황추론에서 시간경과를 고려한 클러스터링 기법)

  • Ryu, Chang-Keun;Park, Chan-Bong
    • The Journal of the Korea institute of electronic communication sciences
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    • v.8 no.3
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    • pp.397-402
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    • 2013
  • Time variation is the essential component of the context awareness. It is a beneficial way not only including time lapse but also clustering time interval for the context inference using the information from sensor mote. In this study, we proposed a novel way of clustering based multi-sensor data fusion for the context inference. In the time interval, we fused the sensed signal of each time slot, and fused again with the results of th first fusion. We could reach the enhanced context inference with assessing the segmented signal according to the time interval at the Dempster-Shafer evidence theory based multi-sensor data fusion.

Reliable Navigation of a Mobile Robot in Cluttered Environment by Combining Evidential Theory and Fuzzy Controller (추론 이론과 퍼지 컨트롤러 결합에 의한 이동 로봇의 자유로운 주변 환경 인식)

  • 김영철;조성배;오상록
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2001.05a
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    • pp.136-139
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    • 2001
  • This paper develops a sensor based navigation method that utilizes fuzzy logic and the Dempster-Shafer evidence theory for mobile robot in uncertain environment. The proposed navigator consists of two behaviors: obstacle avoidance and goal seeking. To navigate reliably in the environment, we make a map building process before the robot finds a goal position and create a robust fuzzy controller. In this paper, the map is constructed on a two-dimensional occupancy grid. The sensor readings are fused into the map using D-S inference rule. Whenever the robot moves, it catches new information about the environment and replaces the old map with new one. With that process the robot can go wandering and finding the goal position. The usefulness of the proposed method is verified by a series of simulations. This paper deals with the fuzzy modeling for the complex and uncertain nonlinear systems, in which conventional and mathematical models may fail to give satisfactory results. Finally, we provide numerical examples to evaluate the feasibility and generality of the proposed method in this paper.

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Feature Extraction and Fusion for land-Cover Discrimination with Multi-Temporal SAR Data (다중 시기 SAR 자료를 이용한 토지 피복 구분을 위한 특징 추출과 융합)

  • Park No-Wook;Lee Hoonyol;Chi Kwang-Hoon
    • Korean Journal of Remote Sensing
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    • v.21 no.2
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    • pp.145-162
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    • 2005
  • To improve the accuracy of land-cover discrimination in SAB data classification, this paper presents a methodology that includes feature extraction and fusion steps with multi-temporal SAR data. Three features including average backscattering coefficient, temporal variability and coherence are extracted from multi-temporal SAR data by considering the temporal behaviors of backscattering characteristics of SAR sensors. Dempster-Shafer theory of evidence(D-S theory) and fuzzy logic are applied to effectively integrate those features. Especially, a feature-driven heuristic approach to mass function assignment in D-S theory is applied and various fuzzy combination operators are tested in fuzzy logic fusion. As experimental results on a multi-temporal Radarsat-1 data set, the features considered in this paper could provide complementary information and thus effectively discriminated water, paddy and urban areas. However, it was difficult to discriminate forest and dry fields. From an information fusion methodological point of view, the D-S theory and fuzzy combination operators except the fuzzy Max and Algebraic Sum operators showed similar land-cover accuracy statistics.

Comparison of Methodologies for Target Identification (표적 식별을 위한 방법론의 비교)

  • 김인택
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1998.10a
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    • pp.454-460
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    • 1998
  • 본 논문은 전장에서의 표적 식별을 위해 다수의 센서가 사용되는 환경에서 요구되는 융합방법론에 대해 간단히 살표 보고 이에 대한 차이점을 비교한다. 다수의 센서를 사용함으로써 각각의 센서가 가진 중복성, 보완성을 활용하여 센서가 제공하는 정보의 불확실성을 줄일수 있는 가능성을 기대할 수 있다. 본 논문에서는 베이지안 알고리즘, Dempster-Shafer 이론 그리고 퍼지 융합 방법 등에 대한 간단히 소개하고 임의의 표적과 특성값을 설정하여 융합 알고리즘간의 성능을 비교하였다.

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Data Fusion Algorithm based on Inference for Anomaly Detection in the Next-Generation Intrusion Detection (차세대 침입탐지에서 이상탐지를 위한 추론 기반 데이터 융합 알고리즘)

  • Kim, Dong-Wook;Han, Myung-Mook
    • Journal of the Korean Institute of Intelligent Systems
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    • v.26 no.3
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    • pp.233-238
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    • 2016
  • In this paper, we propose the algorithms of processing the uncertainty data using data fusion for the next generation intrusion detection. In the next generation intrusion detection, a lot of data are collected by many of network sensors to discover knowledge from generating information in cyber space. It is necessary the data fusion process to extract knowledge from collected sensors data. In this paper, we have proposed method to represent the uncertainty data, by classifying where is a confidence interval in interval of uncertainty data through feature analysis of different data using inference method with Dempster-Shafer Evidence Theory. In this paper, we have implemented a detection experiment that is classified by the confidence interval using IRIS plant Data Set for anomaly detection of uncertainty data. As a result, we found that it is possible to classify data by confidence interval.

On the Adjustment of Weight of Multiple Decision Making Group Problems (다수 의사결정 그룹 문제의 가중치 조정에 관한 연구)

  • Yeo Ki-Tae;Ryu Hyung-Geun;Lee Hong-Girl
    • Journal of Navigation and Port Research
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    • v.29 no.1 s.97
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    • pp.59-64
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    • 2005
  • MDMG(Multiple Decision-Making Group) problems comprise those of UDMG(Unit Decision-Making Group) which contradict each other. For the evaluation problem of port competitiveness, it has the complicated evaluation characteristics of multi-strata-complex and multi-attributes. Especially, it becomes typical MDMG problems in the evaluation which a great number of decision makers such as shipping companies, freight forwarders, logistics companies and researchers participate in This evaluation of complex problems needs the compensated process of weight which rationally unites heterogeneous preferences of each of groups. In this respect, the purpose of this study is to remove the uncertainty of the UDMG using the theory of DS (Dempster-Shafer) and present the integrated weight through the level process.

An Intelligent Call Center based on Agent (Agent를 기반으로 한 지능형 호출 시스템)

  • Lee, Dong-Kyu;Han, Kyung-Sook
    • Journal of KIISE:Computing Practices and Letters
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    • v.7 no.5
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    • pp.522-538
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    • 2001
  • This paper presents a cal center which is a subsystem of a web-based real time monitoring system of intensive care units. Based on Computer-Telephony Integration (CTI) technology, the call center attempts to efficiently and automatically send messages to patients\` families, doctors, and other staffs in hospital via communication media suitable to the occasion. The problem of determining appropriate media can be very complicated by the urgency of a message, calling time, and communication media available to the target person. We use the Dempster-Shafer theory, one of the uncertainty handling methods, to determine the most suitable communication media that will transmit a message rapidly and safely. In addition, we use agent technology to perform the calling process without requiring the intervention of the user of the call center. this call center enables message transfer through various communication media in an integrated environment, and relieves medical staff from the calling process, which in turn will make a contribution toward enhancing medical service.

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전문가 시스템의 불확실성 추론 방법

  • 이승재
    • 전기의세계
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    • v.39 no.8
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    • pp.7-12
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    • 1990
  • 전문가 시스템에 있어서의 불확실성 정보의 표현 및 처리를 담당하는 주요 추론모델중 Bayesian모델, Certainty Factor 모델 그리고 Dempster-Shafer 모델의 기본이론을 살펴보고자 한다. 이외의 주요 추론 방법으로서 Fuzzy추론 모델이 있는데 이는 판단 지식에 대한 주관적 불확실성과 "매우", "많이" 등의 자연어가 포함하고 있는 불분명성을 체계적이고 효과적으로 다룰 수 있는 Fuzzy Set 이론에 근거한 방법으로서, 불확실성 또는 불명료성을 0에서부터 1 사이의 값을 갖는 membership degree로 표시하며 이를 "MIN"과 "MAX" 함수를 이용한 합성 추론 규칙(Composition Rule of Inference)를 적용하여 처리한다. Fuzzy 추론 모델은 자연어를 포함하는 전문가의 지식 처리에 매우 적합하여 앞으로 그 응용이 높이 기대되는 방법이다. 이외에 Bayesian 모델을 변형 응용한 PROSPECTOR의 Likelyhood Ratio 모델, 정량적 방법인 Theory of Endorsement 모델 등 여러 방법이 있다. 그러나 어느 모델이 더 일반성을 갖고 더 좋은 방법인가 하는 문제에 대하여는 아직 많은 연구가 요구된다. 따라서 이러한 모델들의 전문가 시스템 적용에 있어서는 각 모델의 장단점을 고려하여 주어진 문제 영역에 적합한 모델을 선택하는 것이 바람직하다. 현재 불확실성 처리에 있어서 각 문제에 따른 경험적인 처리에 의존하는 전력 계통 분야의 적용에 있어서도 이러한 실인간 전문가의 추론방법에 근접된 반성을 갖는 불확실성 추론 방버 도입이 요구된다.가의 추론방법에 근접된 반성을 갖는 불확실성 추론 방버 도입이 요구된다.

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