• Title/Summary/Keyword: graph structure

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A Study on Data Quality Management in Business Intelligence Environments (비즈니스 인텔리전스 환경에서 변환 관리를 이용한 데이터 품질 향상에 대한 연구)

  • Lee, Choon-Yeul
    • Information Systems Review
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    • v.6 no.2
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    • pp.65-77
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    • 2004
  • Business intelligence assumes an integrated and inter-connected information resources. To manage an integrated database, we need to trace data transformation processes from its outset. For this purpose, this study proposes an extended Information Structure Graph that models data transformation steps in addition to data transformation structures. Using the graph, we can identify relationship among data entities and assign data quality measures to each nodes or arcs of a graph, thus eases management of data and enhancing their quality.

Reliability Evaluation of Electrical Distribution Network Containing Distributed Generation Using Directed-Relation-Graph

  • Yang, He-Jun;Xie, Kai-Gui;Wai, Rong-Jong;Li, Chun-Yan
    • Journal of Electrical Engineering and Technology
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    • v.9 no.4
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    • pp.1188-1195
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    • 2014
  • This paper presents an analytical technique for reliability evaluation of electrical distribution network (EDN) containing distributed generation (DG). Based on hierarchical levels of circuit breaker controlling zones and feeder sections, a directed-relation-graph (DRG) for an END is formed to describe the hierarchical structure of the EDN. The reliability indices of EDN and load points can be evaluated directly using the formed DRG, and the reliability evaluation of an EDN containing DGs can also be done without re-forming the DRG. The proposed technique incorporates multi-state models of photovoltaic and diesel generations, as well as weather factors. The IEEE-RBTS Bus 6 EDN is used to validate the proposed technique; and a practical campus EDN containing DG was also analyzed using the proposed technique.

RAG-based Image Segmentation Using Multiple Windows (RAG 기반 다중 창 영상 분할 (1))

  • Lee, Sang-Hoon
    • Korean Journal of Remote Sensing
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    • v.22 no.6
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    • pp.601-612
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    • 2006
  • This study proposes RAG (Region Adjancency Graph)-based image segmentation for large imagery in remote sensing. The proposed algorithm uses CN-chain linking for computational efficiency and multi-window operation of sliding structure for memory efficiency. Region-merging due to RAG is a process to find an edge of the best merge and update the graph according to the merge. The CN-chain linking constructs a chain of the closest neighbors and finds the edge for merging two adjacent regions. It makes the computation time increase as much as an exact multiple in the increasement of image size. An RNV (Regional Neighbor Vector) is used to update the RAG according to the change in image configuration due to merging at each step. The analysis of large images requires an enormous amount of computational memory. The proposed sliding multi-window operation with horizontal structure considerably the memory capacity required for the analysis and then make it possible to apply the RAG-based segmentation for very large images. In this study, the proposed algorithm has been extensively evaluated using simulated images and the results have shown its potentiality for the application of remotely-sensed imagery.

Verification and Evaluation of Spatial Structure Theory through Discrete Event Simulation (이산사건 시뮬레이션을 이용한 공간구조론의 검증 및 평가)

  • Yoon, So Hee;Kim, Suk Tae
    • Journal of Korea Multimedia Society
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    • v.19 no.12
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    • pp.2000-2013
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    • 2016
  • The purpose of this study is to validate the validity of the methodology for analyzing the space with complex characteristics and to evaluate the existing spatial structure analysis theory. Seven example models are designed and analyzed data of spatial syntax analysis and visibility graph analysis. And analyzed the agent-based model using two analytical methods: the adjacent space and the whole spatial connection. The results of this study are as follows. Based on the analysis of the agent - based model for perfectly freewalking, the validity of the method is verified in terms of predictive ability and effectiveness. Agent-based models can be simulated considering various variables, so realistic predictions will be possible and a new biography of complex systems can be met.

Model Test for the Damage Assessment of Adjacent Frame Structures in Urban Excavation (지반 굴착에 따른 인접 프레임구조물의 손상평가에 관한 모형실험 연구)

  • Kim, Seong-Cheol;Hwang, Eui-Seok;Kim, Zu-Cheol;Kim, Hak-Moon
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.1490-1495
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    • 2005
  • In this study, Model test of concrete frame structures with various shapes and locations are carried out by means of applying Peck's(1969) settlement method. The results of the model test indicated that important correlations existed between the behavior of frame structure and ground movement. Also, the damage level of frame structure closely influenced by the phase of excavation. Therefore, prediction of damage level at early phase of construction should be very precise. The damage level graph by Cording et al.(2001), the angular distortion provided gradually more serious damage to frame structures for the all cases. But the damage level graph by Burland(1997), was difficult to confirm because of very small amount of deflection ratio.

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physical structure of dynamic systems to implement a given system function (시스템함수를 실현하는 동적시스템의 물리구조에 관하여)

  • 박전수;김종식
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.04a
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    • pp.294-298
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    • 1996
  • This paper presents an attempt to find the physical structure of dynamic systems which achieves the behavior of a given system function. The scheme pursued by te paper would be regarded as synthesizing dynamic systems, and a method to synthesize them analytically is proposed by means of bond graph prototypes. The method proposed adopts several concepts used to synthesize networks in the electrical field, but yet demonstrates its own strengths such as the freedom from the causality assignment and determination of junction types. Also, it is shown that this method has further advantages in reticulating a given specification into feedforward and feedback expansions relative to electrical network synthesis and the method introduced by Redfield. The proposed method is examined through an example to trace the outline of the analytical synthesis of dynamic systems using bond graph prototypes.

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A Model Formalization Methodology of Discrete Event Simulation with Formal Tools (형식 도구를 이용한 이산사건 시뮬레이션의 모델 형식화 방법론)

  • ;;Jeong, Young Sik;Baik, Doo Kwon
    • Journal of the Korean Operations Research and Management Science Society
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    • v.17 no.3
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    • pp.79-99
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    • 1992
  • The DEVS (Discrete Event system Specification) formal model for discrete event simulation is a hierarchical, modular model. Because the DEVS formal model has a mathematical structure, it provides a theoretic background of discrete event simulation model. However, the DEVS formal model is difficult to understand because of its mathematical structure. Also, since the DEVS formal model is often constructed by heuristic, subjective method of model designer from the model, a systematic model built-in methodology does not exist. In this paper, we propose the model formalization methodology from an informal model to the DEVS formal model. For this formalization methodology, we introduce formal tools for model construction based on the DEVS ( from an informal model : Event Dependency Graph (EDG) for the event analysis and State Representation Graph(SRG) for the system state analysis.

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Shared Spatio-temporal Attention Convolution Optimization Network for Traffic Prediction

  • Pengcheng, Li;Changjiu, Ke;Hongyu, Tu;Houbing, Zhang;Xu, Zhang
    • Journal of Information Processing Systems
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    • v.19 no.1
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    • pp.130-138
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    • 2023
  • The traffic flow in an urban area is affected by the date, weather, and regional traffic flow. The existing methods are weak to model the dynamic road network features, which results in inadequate long-term prediction performance. To solve the problems regarding insufficient capacity for dynamic modeling of road network structures and insufficient mining of dynamic spatio-temporal features. In this study, we propose a novel traffic flow prediction framework called shared spatio-temporal attention convolution optimization network (SSTACON). The shared spatio-temporal attention convolution layer shares a spatio-temporal attention structure, that is designed to extract dynamic spatio-temporal features from historical traffic conditions. Subsequently, the graph optimization module is used to model the dynamic road network structure. The experimental evaluation conducted on two datasets shows that the proposed method outperforms state-of-the-art methods at all time intervals.

Direct synthesis method of dynamic systems in terms of bond graphs (본드선도를 이용한 동적시스템의 직접 종합방법)

  • Park, Jeon-Soo;Kim, Jong-Shik
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.22 no.2
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    • pp.399-407
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    • 1998
  • This paper deals with a method for finding the physical structure of dynamic systems which shows reasonable response to a given specifiation. The method uses only four basic models of bond graph prototypes which have been originally proposed by the authors as a general model for dynamic systems, and then makes its procedure highly physical in the sense that it can synthesize a dynamic system through the structural transformation directly on bond graph models without any mathematical manipulation. Also, it is shown that this method has further advantages in optimizing parameters for an existing system rather than developing design concepts for a new device, the latter being more suitable using the so-called analytical synthesis method introduced by Park and Redfield. One example serves to trace the outlines of the direct synthesis method proposed in this paper for dynamic systems in terms of bond graph prototypes.

Topological Properties of Recursive Circulants : Disjoint Cycles and Graph Invariants (재귀원형군의 위상 특성 : 서로소인 사이클과 그래프 invariant)

  • Park, Jeong-Heum;Jwa, Gyeong-Ryong
    • Journal of KIISE:Computer Systems and Theory
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    • v.26 no.8
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    • pp.999-1007
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    • 1999
  • 이 논문은 재귀원형군 G(2^m , 2^k )를 그래프 이론적 관점에서 고찰하고 정점이 서로소인 사이클과 그래프 invariant에 관한 위상 특성을 제시한다. 재귀원형군은 1 에서 제안된 다중 컴퓨터의 연결망 구조이다. 재귀원형군 {{{{G(2^m , 2^k )가 길이 사이클을 가질 필요 충분 조건을 구하고, 이 조건하에서 G(2^m , 2^k )는 가능한 최대 개수의 정점이 서로소이고 길이가l`인 사이클을 가짐을 보인다. 그리고 정점 및 에지 채색, 최대 클릭, 독립 집합 및 정점 커버에 대한 그래프 invariant를 분석한다.Abstract In this paper, we investigate recursive circulant G(2^m , 2^k ) from the graph theory point of view and present topological properties of G(2^m , 2^k ) concerned with vertex-disjoint cycles and graph invariants. Recursive circulant is an interconnection structure for multicomputer networks proposed in 1 . A necessary and sufficient condition for recursive circulant {{{{G(2^m , 2^k ) to have a cycle of lengthl` is derived. Under the condition, we show that G(2^m , 2^k ) has the maximum possible number of vertex-disjoint cycles of length l`. We analyze graph invariants on vertex and edge coloring, maximum clique, independent set and vertex cover.