• Title/Summary/Keyword: Graph-based

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Estimation of the Medium Transmission Using Graph-based Image Segmentation and Visibility Restoration (그래프 기반 영역 분할 방법을 이용한 매체 전달량 계산과 가시성 복원)

  • Kim, Sang-Kyoon;Park, Jong-Hyun;Park, Soon-Young
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.4
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    • pp.163-170
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    • 2013
  • In general, images of outdoor scenes often contain degradation due to dust, water drop, haze, fog, smoke and so on, as a result they cause the contrast reduction and color fading. Haze removal is not easier problem due to the inherent ambiguity between the haze and the underlying scene. So, we propose a novel method to solve single scene dehazing problem using the region segmentation based on graph algorithm that has used a gradient value as a cost function. We segment the scene into different regions according to depth-related information and then estimate the global atmospheric light. The medium transmission can be directly estimated by the threshold function of graph-based segmentation algorithm. After estimating the medium transmission, we can restore the haze-free scene. We evaluated the degree of the visibility restoration between the proposed method and the existing methods by calculating the gradient of the edge between the restored scene and the original scene. Results on a variety of outdoor haze scene demonstrated the powerful haze removal and enhanced image quality of the proposed method.

Resource Scheduling Framework based on Resource Parameter Graph (자원인자 기반 스케줄링 프레임워크)

  • 배재환;권성호;김덕수;이강우
    • Journal of Korea Society of Industrial Information Systems
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    • v.8 no.3
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    • pp.19-31
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    • 2003
  • For the implementation of large scale GRID systems, the performance scalability in resource scheduling is clearly to be addressed. In this research, we analyzed existing scheduling frameworks from the viewpoint of the performance and propose a novel resource scheduling framework called resource parameter based scheduling. Proposed scheduling framework consists of three components. The first is the resource parameter graph that expresses resource information via inter-resource relation and the composition base on the hierarchical structure. The second component is the resource parameter tree to be used for the implementation of the memory-based index of resource information. The third component is the resource information repository which mostly consists of static data to be used for the general resource information services. This paper presents the details of the framework.

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Spatial Configuration Analysis of the Elderly Care Facilities Based on Visibility - Visibility Analysis and Agent-Based Simulation Using Space Syntax - (가시성에 기반한 노인요양시설의 공간계획에 관한 분석 - 공간구문론을 활용한 가시성 분석과 에이전트 시뮬레이션을 중심으로 -)

  • Lee, Jisun;Lee, Hyunsoo
    • Korean Institute of Interior Design Journal
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    • v.27 no.3
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    • pp.14-23
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    • 2018
  • The spatial planning of the elderly care facility plans is analyzed using space syntax in terms of encouraging the social interaction of the residents in this study. First, through the visibility graph analysis, openness and accessibility of space is analysed. Second, the walking behavior of residents through agent analysis model is simulated. Third, the space planning methods for the elderly care facilities are proposed based on the results. The results are as follows. According to the visibility graph analysis, the main corridor has high visual openness and high accessibility. The visual openness and accessibility of the unit living room, where social interaction among residents is possible in each unit, is low. Space planning is needed to increase direct protection and observation of employees to the unit living room. The location of the nurse station that manages the entire floor needs to be located where the openness and accessibility is most high. The nursing station should have a high degree of connectivity to the entire space, so that any accidents can be managed and contact is accessible. Through the agent simulation the flow from the center to each unit space is highest in the corridor space and the inflow to the private rooms and the living room are similar. Therefore, it is necessary to plan the accessibility of the unit living room more for the natural inflow of residents.

A JCML and a GUI-based Editor for Specifying Job Control Flow on Grid (그리드에서 작업 흐름을 효과적으로 제어하기 위한 JCML과 GUI 기반의 편집기)

  • 황석찬;최재영;이상산
    • Journal of KIISE:Computer Systems and Theory
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    • v.31 no.3_4
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    • pp.152-159
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    • 2004
  • The Grid system is an emerging computing infrastructure that will substitute for existing distributed systems. However end users have a difficulty in using the Grid because of its complicated usage, which is an inherent characteristic from the heterogeneous mechanism of the Grid. In this paper, we present the JCML(Job Control Markup Language) and its GUI-based editor, which not only provide users with ease of use, improved working environment, but assist users to execute their jobs efficiently The JCML is a job control language that improves the RSL of Globus, which defines global services in Grid. The JCML is designed to support flexibility among various Grid services using standard XML. And it makes use of a graph representation method, GXL(Graph eXchange Language), to specify detailed job properties and dependencies among jobs using nodes and edges. The JCML editor provides users with GUI-based interface. With the JCML editor, a complicated job order can be easily completed using very simple manipulations with a mouse, such as a drag-and-drop.

Graph Representation by Medial Axis Transform Image for 3D Retrieval (3차원 영상 검색을 위한 중심축 변환에 의한 그래프 표현 기법)

  • Kim, Deok-Hun;Yun, Il-Dong;Lee, Sang-Uk
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.38 no.1
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    • pp.33-42
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    • 2001
  • Recently, the interests in the 3D image, generated from the range data and CAD, have exceedingly increased, accordingly a various 3D image database is being constructed. The efficient and fast scheme to access the desired image data is the important issue in the application area of the Internet and digital library. However, it is difficult to manage the 3D image database because of its huge size. Therefore, a proper descriptor is necessary to manage the data efficiently, including the content-based search. In this paper, the proposed shape descriptor is based on the voxelization of the 3D image. The medial axis transform, stemming from the mathematical morphology, is performed on the voxelized 3D image and the graph, which is composed of node and edge, is generated from skeletons. The generated graph is adequate to the novel shape descriptor due to no loss of geometric information and the similarity of the insight of the human. Therefore the proposed shape descriptor would be useful for the recognition of 3D object, compression, and content-based search.

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A Study on Real-time State Estimation for Smart Microgrids (스마트 마이크로그리드 실시간 상태 추정에 관한 연구)

  • Bae, Jun-Hyung;Lee, Sang-Woo;Park, Tae-Joon;Lee, Dong-Ha;Kang, Jin-Kyu
    • 한국태양에너지학회:학술대회논문집
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    • 2012.03a
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    • pp.419-424
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    • 2012
  • This paper discusses the state-of-the-art techniques in real-time state estimation for the Smart Microgrids. The most popular method used in traditional power system state estimation is a Weighted Least Square(WLS) algorithm which is based on Maximum Likelihood(ML) estimation under the assumption of static system state being a set of deterministic variables. In this paper, we present a survey of dynamic state estimation techniques for Smart Microgrids based on Belief Propagation (BP) when the system state is a set of stochastic variables. The measurements are often too sparse to fulfill the system observability in the distribution network of microgrids. The BP algorithm calculates posterior distributions of the state variables for real-time sparse measurements. Smart Microgrids are modeled as a factor graph suitable for characterizing the linear correlations among the state variables. The state estimator performs the BP algorithm on the factor graph based the stochastic model. The factor graph model can integrate new models for solar and wind correlation. It provides the Smart Microgrids with a way of integrating the distributed renewable energy generation. Our study on Smart Microgrid state estimation can be extended to the estimation of unbalanced three phase distribution systems as well as the optimal placement of smart meters.

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A Practical RWA Algorithm-based on Lookup Table for Edge Disjoint Paths (EDP들의 참조 테이블을 이용한 실용적 인 경로 설정 및 파장 할당 알고리즘)

  • 김명희;방영철;정민영;이태진;추현승
    • Journal of KIISE:Information Networking
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    • v.31 no.2
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    • pp.123-130
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    • 2004
  • Routing and wavelength assignment(RWA) problem is an important issue in optical transport networks based on wavelength division multiplexing(WDM) technique. It is typically solved using a combination of linear programming and graph coloring, or path selection based graph algorithms. Such methods are either complex or make extensive use of heuristics. In this paper we propose a novel and efficient approach which basically obtains the maximum edge disjoint paths (EDPs) for each source-destination demand pair. And those EDPs obtained are stored in Lookup Table and used for the update of weight matrix. Routes are determined in order by the weight matrix for the demand set. The comprehensive computer simulation shows that the Proposed algorithm uses similar or fewer wavelengths with significantly less execution time than bounded greedy approach (BGA) for EDP which is currently known to be effective in practice.

Generating a Korean Sentiment Lexicon Through Sentiment Score Propagation (감정점수의 전파를 통한 한국어 감정사전 생성)

  • Park, Ho-Min;Kim, Chang-Hyun;Kim, Jae-Hoon
    • KIPS Transactions on Software and Data Engineering
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    • v.9 no.2
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    • pp.53-60
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    • 2020
  • Sentiment analysis is the automated process of understanding attitudes and opinions about a given topic from written or spoken text. One of the sentiment analysis approaches is a dictionary-based approach, in which a sentiment dictionary plays an much important role. In this paper, we propose a method to automatically generate Korean sentiment lexicon from the well-known English sentiment lexicon called VADER (Valence Aware Dictionary and sEntiment Reasoner). The proposed method consists of three steps. The first step is to build a Korean-English bilingual lexicon using a Korean-English parallel corpus. The bilingual lexicon is a set of pairs between VADER sentiment words and Korean morphemes as candidates of Korean sentiment words. The second step is to construct a bilingual words graph using the bilingual lexicon. The third step is to run the label propagation algorithm throughout the bilingual graph. Finally a new Korean sentiment lexicon is generated by repeatedly applying the propagation algorithm until the values of all vertices converge. Empirically, the dictionary-based sentiment classifier using the Korean sentiment lexicon outperforms machine learning-based approaches on the KMU sentiment corpus and the Naver sentiment corpus. In the future, we will apply the proposed approach to generate multilingual sentiment lexica.

Enhanced Methods of Path Finding Based on An Abstract Graph with Extension of Search Space (탐색 영역 확장 기법들을 활용한 추상 그래프 기반의 탐색 알고리즘 성능 개선)

  • Cho, Dae-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.1
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    • pp.157-162
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    • 2011
  • In this paper, we propose enhanced methods of path finding based on an abstract graph with extension of search space to improve the quality of path. The proposed methods that are called simple buffering method, velocity constrained method and distance constrained method are to extract buffering-cells for using search space with valid-cells. The simple buffering method is to extract adjacent cells of valid-cells as buffering-cells. velocity constrained method and distance constrained method are based on simple buffering method, these eliminate buffering-cells through each of threshold. In experiment, proposed methods can improve the quality of path. The proposed methods are applicable to develop various kinds of telematics application, such as path finding and logistics.

An Approach to Support Software Architecture Transformation in Architecture-Based Software Development (아키텍처 기반 소프트웨어 개발에서 소프트웨어 아키텍처 변형을 지원하기 위한 방법)

  • Choi Heeseok;Yeom Keunhyuk
    • Journal of KIISE:Software and Applications
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    • v.32 no.1
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    • pp.10-21
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    • 2005
  • Software architecture is increasingly being viewed as a key design in developing complex software systems, which largely affects the achievement of quality attributes. During the architecture-based software development, therefore, architectural transformation is needed to achieve quality attributes. Due to the variety of design alternatives and the poor predictability of the effects of the transformation, however, it is not easy to apply architectural transformation. Therefore, the method is needed to support architectural transformation through systematically analyzing the effects of applying various design alternatives to the architecture. This paper proposes an approach to support software architecture transformation. Based on architectural design decisions and the constraints on them included in the architecture, our approach defines a decision constraint graph representing the dependencies among architectural design decisions. Through using the decision constraint graph, architectural transformation can be systematically performed by understanding the effects of applying a transformation. While this work supports more understanding of applying architectural transformation, it also helps reconstruct a software architecture to improve the quality of the software.