• Title/Summary/Keyword: Dependency Network

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An Extended Version of the CPT-based Estimation for Missing Values in Nominal Attributes

  • Ko, Song;Kim, Dae-Won
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.10 no.4
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    • pp.253-258
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    • 2010
  • The causal network represents the knowledge related to the dependency relationship between all attributes. If the causal network is available, the dependency relationship can be employed to estimate the missing values for improving the estimation performance. However, the previous method had a limitation in that it did not consider the bidirectional characteristic of the causal network. The proposed method considers the bidirectional characteristic by applying prior and posterior conditions, so that it outperforms the previous method.

Multiple Perspectives on Knowledge Management : Social Network, Resource Dependency, and Institutionalization Theories (지식경영에 대한 제 접근 : 사회적 네트워크, 자원의존 및 제도화 이론을 중심으로)

  • Moon, Gyewan;Kim, Kiwhan;Choi, Sukbong
    • Knowledge Management Research
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    • v.10 no.4
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    • pp.43-60
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    • 2009
  • The current study attempts to provide the field of knowledge management with theoretical grounds from the perspective of social network, resource dependency, and institutional theory. Social network theory considers that knowledge management plays a critical role in organizational innovation through the process of knowledge sharing/creation, communication systems, and a cooperative culture and trust, whereas resource dependency perceives knowledge management as contributing to cost reduction through the process of knowledge capture/storage, database systems, and reward/incentive systems. Plus, from the perspective of institutionalization, this study discusses that organizations can not benefit from knowledge management if it is adopted with the motive of isomorphic change. Finally, this study compares and integrates the three perspectives, and discusses the implications and limitations.

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Designn and Implementation Online Customer Reviews Analysis System based on Dependency Network Model (종속성 네트워크 기반의 온라인 고객리뷰 분석시스템 설계 및 구현)

  • Kim, Keun-Hyung
    • The Journal of the Korea Contents Association
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    • v.10 no.11
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    • pp.30-37
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    • 2010
  • It is very important to analyze online customer reviews, which are small documents of writing opinions or experiences about products or services, for both customers and companies because the customers can get good informations and the companies can establish good marketing strategies. In this paper, we did not propose only dependency network model which is tool for analyzing online customer reviews, but also designed and implemented the system based on the dependency network model. The dependency network model analyzes both subjective and objective sentences, so that it can represent relative importance and relationship between the nouns in the sentences. In the result of implementing, we recognized that relative importance and relationship between the features of products or services, which can not be mined by opinion mining, can be represented by the dependency network model.

Improvement of Initial Weight Dependency of the Neural Network Model for Determination of Preconsolidation Pressure from Piezocone Test Result (피에조콘을 이용한 선행압밀하중 결정 신경망 모델의 초기 연결강도 의존성 개선)

  • Park, Sol-Ji;Joo, No-Ah;Park, Hyun-Il;Kim, Young-Sang
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.456-463
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    • 2009
  • The preconsolidation pressure has been commonly determined by oedometer test. However, it can also be determined by in-situ test, such as piezocone test with theoretical and(or) empirical correlations. Recently, Neural Network(NN) theory was applied and some models were proposed to estimate the preconsolidation pressure or OCR. However, since the optimization process of synaptic weights of NN model is dependent on the initial synaptic weights, NN models which are trained with different initial weights can't avoid the variability on prediction result for new database even though they have same structure and use same transfer function. In this study, Committee Neural Network(CNN) model is proposed to improve the initial weight dependency of multi-layered neural network model on the prediction of preconsolidation pressure of soft clay from piezocone test result. It was found that even though the NN model has the optimized structure for given training data set, it still has the initial weight dependency, while the proposed CNN model can improve the initial weight dependency of the NN model and provide a consistent and precise inference result than existing NN models.

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User Preference Prediction & Personalized Recommendation based on Item Dependency Map (IDM을 기반으로 한 사용자 프로파일 예측 및 개인화 추천 기법)

  • 염선희
    • Proceedings of the IEEK Conference
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    • 2003.11b
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    • pp.211-214
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    • 2003
  • In this paper, we intend to find user's TV program choosing pattern and, recommend programs that he/she wants. So we suggest item dependency map which express relation between chosen program. Using an algorithm that we suggest, we can recommend an program, which a user has not saw yet but maybe is likely to interested in. Item dependency map is used as patterns for association in hopfield network so we can extract users global program choosing pattern only using users partial information. Hopfield network can extract global information from sub-information. Our algorithm can predict user's inclination and recommend an user necessary information.

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Reliability Modeling and Computational Algorithm of Network Systems with Dependent Components (구성요소가 서로 종속인 네트워크시스템의 신뢰성모형과 계산알고리즘)

  • 홍정식;이창훈
    • Journal of the Korean Operations Research and Management Science Society
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    • v.14 no.1
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    • pp.88-96
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    • 1989
  • General measure in the reliability is the k-terminal reliability, which is the probability that the specified vertices are connected by the working edges. To compute the k-terminal reliability components are usually assumed to be statistically independent. In this study the modeling and analysis of the k-terminal reliability are investigated when dependency among components is considered. As the size of the network increases, the number of the joint probability parameter to represent the dependency among components is increasing exponentially. To avoid such a difficulty the structured-event-based-reliability model (SERM) is presented. This model uses the combination of the network topology (physical representation) and reliability block diagram (logical representation). This enables us to represent the dependency among components in a network form. Computational algorithms for the k-terminal reliability in SERM are based on the factoring algorithm Two features of the ractoring algorithm are the reliability preserving reduction and the privoting edge selection strategy. The pivoting edge selction strategy is modified by two different ways to tackle the replicated edges occuring in SERM. Two algorithms are presented according to each modified pivoting strategy and illustrated by numerical example.

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Personalized Recommendation based on Item Dependency Map (전자상거래를 위한 Item Dependency Map 기반 개인화된 추천기법)

  • 염선희;조동섭
    • Proceedings of the Korean Information Science Society Conference
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    • 2001.04b
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    • pp.475-477
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    • 2001
  • 본 논문은 사용자의 구매 패턴을 찾아서 사용자가 원하는 상품을 추천하는 알고리즘을 제안하고자 한다. 제안하고 있는 item dependency map은 구매된 상품간의 관계를 수식화 하여 행렬의 형태로 표현한 것이다. Item dependency map의 값은 사용자가 A라는 상품을 구매한 후 B 상품을 살 확률이다. 이런 정보를 가지고 있는 item dependency map은 홉필드 네트웍(Hopfield network)에서 연상을 위한 패턴 값으로 적용된다. 홉필드 네트웍은 각 노드사이의 연결가중치에 기억하고자 하는 것들을 연상시킨 뒤 어떤 입력을 통해서 전체 네트워크가 어떤 평형상태에 도달하는 방식으로 작동되는 신경망 중의 하나이다. 홉필드 네트웍의 특징 중의 하나는 부분 정보로부터 전체 정보를 추출할 수 있는 것이다. 이러한 특징을 가지고 사용자들의 일반적인 구매패턴을 일부 정보만 가지고 예측할 수 있다. Item dependency map은 홉필드 네트웍에서 사용자들의 그룹별 패턴을 학습하는데 사용된다. 따라서 item dependency map이 얼마나 사용자 구매패턴에 대한 정보를 가지고 있는지에 따라 그 결과가 결정되는 것이다. 본 논문은 정확한 item dependency map을 계산해 내는 알고리즘을 주로 논의하겠다.

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Recent developments of constructing adjacency matrix in network analysis

  • Hong, Younghee;Kim, Choongrak
    • Journal of the Korean Data and Information Science Society
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    • v.25 no.5
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    • pp.1107-1116
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    • 2014
  • In this paper, we review recent developments in network analysis using the graph theory, and introduce ongoing research area with relevant theoretical results. In specific, we introduce basic notations in graph, and conditional and marginal approach in constructing the adjacency matrix. Also, we introduce the Marcenko-Pastur law, the Tracy-Widom law, the white Wishart distribution, and the spiked distribution. Finally, we mention the relationship between degrees and eigenvalues for the detection of hubs in a network.

An Evidence Retraction Scheme on Evidence Dependency Network

  • Lee, Gye Sung
    • International journal of advanced smart convergence
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    • v.8 no.1
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    • pp.133-140
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    • 2019
  • In this paper, we present an algorithm for adjusting degree of belief for consistency on the evidence dependency network where various sets of evidence support different sets of hypotheses. It is common for experts to assign higher degree of belief to a hypothesis when there is more evidence over the hypothesis. Human expert without knowledge of uncertainty handling may not be able to cope with how evidence is combined to produce the anticipated belief value. Belief in a hypothesis changes as a series of evidence is known to be true. In non-monotonic reasoning environments, the belief retraction method is needed to clearly deal with uncertain situations. We create evidence dependency network from rules and apply the evidence retraction algorithm to refine belief values on the hypothesis set. We also introduce negative belief values to reflect the reverse effect of evidence combination.

Bidirectional Stack Pointer Network for Korean Dependency Parsing (Bidirectional Stack Pointer Network를 이용한 한국어 의존 파싱)

  • Hong, Seung-Yean;Na, Seung-Hoon;Shin, Jong-Hoon;Kim, Young-Kil
    • Annual Conference on Human and Language Technology
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    • 2018.10a
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    • pp.19-22
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    • 2018
  • 본 논문에서는 기존 Stack Pointer Network의 의존 파싱 모델을 확장한 Bi-Stack Pointer Network를 제안한다. Stack Pointer Network는 기존의 Pointer Network에 내부 stack을 만들어 전체 문장을 읽어 dependency tree를 구성한다. stack은 tree의 깊이 우선 탐색을 통해 선정되고 Pointer Network는 stack의 top 단어(head)의 자식(child)을 선택한다. 제안한 모델은 기존의 Stack Pointer Network가 지배소(head)정보로 의존소(child)를 예측하는 부분에 Biaffine attention을 통해 의존소(child)에서 지배소(head)를 예측하는 방향을 추가하여 양방향 예측이 가능하게 한 모델이다. 실험 결과, 제안 Bi-Stack Pointer Network모델은 UAS 91.53%, LAS 90.93%의 성능을 보여주어 기존 최고 성능을 개선시켰다.

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