• Title/Summary/Keyword: semantic resources

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A Study on Querying Method for RDF Data in XML Database (RDF 데이터 관리를 위한 효율적인 질의 처리에 관한 연구)

  • Hwang NamGoong;Kim Yong
    • Journal of Korean Library and Information Science Society
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    • v.37 no.3
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    • pp.415-431
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    • 2006
  • The semantic web was proposed as the next generation web technology. In the environment of the semantic web, resources as well defined and related with each other semantically, the RDF supports this basic mechanism. To establish and develop the semantic web. the basic technologies related to RDF data must be pre-established. In this research, we develop methods for storing and querying RDF data using an XML database system. As using XML database, XML data and RDF data can be integrated and efficiently managed. We construct and evaluate a system applying the proposed method to store and search data, we compared the query processing performance on our system with that of an existing system. The experiment result show that our system processes queries more efficiently.

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A Novel Method for Matching between RDBMS and Domain Ontology

  • Lee, Ki-Jung;WhangBo, Taeg-Keun
    • Journal of Korea Multimedia Society
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    • v.9 no.12
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    • pp.1552-1559
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    • 2006
  • In a web environment, similar information exists in many different places in diverse formats. Even duplicate information is stored in the various databases using different terminologies. Since most information serviced in the current World Wide Web however had been constructed before the advent of ontology, it is practically almost impossible to construct ontology for all those resources in the web. In this paper, we assume that most information in the web environment exist in the form of RDBMS, and propose a matching method between domain ontology and existing RDBMS tables for semantic retrieval. In the processing of extracting a local ontology, some problems such as losing domain in formation can occur since the correlation of domain ontology has not been considered at all. To prevent these problems, we propose an instance-based matching which uses relational information between RDBMS tables and relational information between classes in domain ontology. To verify the efficiency of the method proposed in this paper, several experiments are conducted using the digital heritage information currently serviced in the countrywide museums. Results show that the proposed method increase retrieval accuracy in terms of user relevance and satisfaction.

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Efficient Classification of User's Natural Language Question Types using Word Semantic Information (단어 의미 정보를 활용하는 이용자 자연어 질의 유형의 효율적 분류)

  • Yoon, Sung-Hee;Paek, Seon-Uck
    • Journal of the Korean Society for information Management
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    • v.21 no.4 s.54
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    • pp.251-263
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    • 2004
  • For question-answering system, question analysis module finds the question points from user's natural language questions, classifies the question types, and extracts some useful information for answer. This paper proposes a question type classifying technique based on focus words extracted from questions and word semantic information, instead of complicated rules or huge knowledge resources. It also shows how to find the question type without focus words, and how useful the synonym or postfix information to enhance the performance of classifying module.

A Semantic-based rate control method for motion video coding (동영상 부호화를 위한 의미 기반 Rate control 기법)

  • 이봉호;전경재;곽노윤;강태하;황병원
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.3B
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    • pp.529-540
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    • 2000
  • This is paper presents the semantic based rate-control method which is based on very low bit rate video coding standards H.263 plus, applied on very low bit rate applications. Previous rate control methods control the generated bit rates by setting the optimum quantization parameters per macro block unit on frame. But, in this paper, we added the pre-processing algorithm, semantic region recognition and assignment of priority algorithm, to obtain the subjective quality enhancement. This work aims to improve the subjective quality of skin color region or face by using unimportant background region's bit resources.

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An Optimization Technique based on Signatures for OWL Query Processing (OWL 질의 처리를 위한 시그너처 기반 최적화 기법)

  • Im Donghyuk;Jeong Hoyoung;Kim Hyoung-Joo
    • Journal of KIISE:Databases
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    • v.32 no.6
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    • pp.585-592
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    • 2005
  • The Semantic Web is being studied as the next step in the evolution of the web. In the environment of the Semantic Web, the information must be understandable computers as well as a just human. So we use ontologies for describing the contents of the web resources. Among such ontologies, OWL is proposed as a recommendation by W3C. OWL data is represented as graph structure and the query is evaluated by traversing each node of the graph. In this paper, we propose the optimization technique based on signature to efficiently process the OWL data. Our approach minimizes traversing each node of the graph in query processing.

Constructing Ontology based on Korean Parts of Speech and Applying to Vehicle Services (한국어 품사 기반 온톨로지 구축 방법 및 차량 서비스 적용 방안)

  • Cha, Si-Ho;Ryu, Minwoo
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.17 no.4
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    • pp.103-108
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    • 2021
  • Knowledge graph is a technology that improves search results by using semantic information based on various resources. Therefore, due to these advantages, the knowledge graph is being defined as one of the core research technologies to provide AI-based services recently. However, in the case of the knowledge graph, since the form of knowledge collected from various service domains is defined as plain text, it is very important to be able to analyze the text and understand its meaning. Recently, various lexical dictionaries have been proposed together with the knowledge graph, but since most lexical dictionaries are defined in a language other than Korean, there is a problem in that the corresponding language dictionary cannot be used when providing a Korean knowledge service. To solve this problem, this paper proposes an ontology based on the parts of speech of Korean. The proposed ontology uses 9 parts of speech in Korean to enable the interpretation of words and their semantic meaning through a semantic connection between word class and word class. We also studied various scenarios to apply the proposed ontology to vehicle services.

A Logical Model of Library System towards Knowledge Service (지식 서비스 지향 도서관 시스템의 논리 모델)

  • Lee, Hyun-Sil;Bae, Chang-Sub;Lee, Eun-Joo;Han, Sung-Kook
    • Journal of the Korean Society for information Management
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    • v.26 no.3
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    • pp.45-67
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    • 2009
  • The ecosystem of the Library has been radically changing in the advent of ubiquitous information service technology. We are already aware of the digital library due to popularizing digital information resources and we are impressed with Library 2.0 and Social Semantic Digital Library of user-centered, service-oriented library. We summarize the ultimate goal of the evolution of library systems as knowledge services and propose a logical model of library system for the realization of knowledge services. This local model can be applied for a library framework to harmonize the diverse knowledge resources, active users with participation and collaboration, the innovation of library business and ubiquitous information service technologies to achieve the missions of library in knowledge-intensive society.

Korean Question-Answering System using Syntactic-Relation Information (구문 관계 정보를 이용한 한국어 질의-응답 시스템)

  • 신승은;이대연;서영훈
    • The Journal of the Korea Contents Association
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    • v.4 no.2
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    • pp.36-42
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    • 2004
  • This paper describes the Korean Question answering system using the syntactic-relation information d verbs to overcome lack of reliable knowledge and linguistic resources. The syntactic-relation information consists d the original form d a verb, usual usage pattern, semantic category of each dependent noun, synonym verbs and passive verbs. We use the syntactic-relation information to parse sentences or phrases with usual usage pattern of the verb and semantic conditions of dependent components on the verb. We also use that information to parse answer candidate sentences, and find an answer from questioned case slot. Our experiments that usage of the syntactic-relation information of verbs to mm lack of reliable knowledge and linguistic resources can be utilized efficiently for the Korean question answering system.

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A Folksonomy Ranking Framework: A Semantic Graph-based Approach (폭소노미 사이트를 위한 랭킹 프레임워크 설계: 시맨틱 그래프기반 접근)

  • Park, Hyun-Jung;Rho, Sang-Kyu
    • Asia pacific journal of information systems
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    • v.21 no.2
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    • pp.89-116
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    • 2011
  • In collaborative tagging systems such as Delicious.com and Flickr.com, users assign keywords or tags to their uploaded resources, such as bookmarks and pictures, for their future use or sharing purposes. The collection of resources and tags generated by a user is called a personomy, and the collection of all personomies constitutes the folksonomy. The most significant need of the folksonomy users Is to efficiently find useful resources or experts on specific topics. An excellent ranking algorithm would assign higher ranking to more useful resources or experts. What resources are considered useful In a folksonomic system? Does a standard superior to frequency or freshness exist? The resource recommended by more users with mere expertise should be worthy of attention. This ranking paradigm can be implemented through a graph-based ranking algorithm. Two well-known representatives of such a paradigm are Page Rank by Google and HITS(Hypertext Induced Topic Selection) by Kleinberg. Both Page Rank and HITS assign a higher evaluation score to pages linked to more higher-scored pages. HITS differs from PageRank in that it utilizes two kinds of scores: authority and hub scores. The ranking objects of these pages are limited to Web pages, whereas the ranking objects of a folksonomic system are somewhat heterogeneous(i.e., users, resources, and tags). Therefore, uniform application of the voting notion of PageRank and HITS based on the links to a folksonomy would be unreasonable, In a folksonomic system, each link corresponding to a property can have an opposite direction, depending on whether the property is an active or a passive voice. The current research stems from the Idea that a graph-based ranking algorithm could be applied to the folksonomic system using the concept of mutual Interactions between entitles, rather than the voting notion of PageRank or HITS. The concept of mutual interactions, proposed for ranking the Semantic Web resources, enables the calculation of importance scores of various resources unaffected by link directions. The weights of a property representing the mutual interaction between classes are assigned depending on the relative significance of the property to the resource importance of each class. This class-oriented approach is based on the fact that, in the Semantic Web, there are many heterogeneous classes; thus, applying a different appraisal standard for each class is more reasonable. This is similar to the evaluation method of humans, where different items are assigned specific weights, which are then summed up to determine the weighted average. We can check for missing properties more easily with this approach than with other predicate-oriented approaches. A user of a tagging system usually assigns more than one tags to the same resource, and there can be more than one tags with the same subjectivity and objectivity. In the case that many users assign similar tags to the same resource, grading the users differently depending on the assignment order becomes necessary. This idea comes from the studies in psychology wherein expertise involves the ability to select the most relevant information for achieving a goal. An expert should be someone who not only has a large collection of documents annotated with a particular tag, but also tends to add documents of high quality to his/her collections. Such documents are identified by the number, as well as the expertise, of users who have the same documents in their collections. In other words, there is a relationship of mutual reinforcement between the expertise of a user and the quality of a document. In addition, there is a need to rank entities related more closely to a certain entity. Considering the property of social media that ensures the popularity of a topic is temporary, recent data should have more weight than old data. We propose a comprehensive folksonomy ranking framework in which all these considerations are dealt with and that can be easily customized to each folksonomy site for ranking purposes. To examine the validity of our ranking algorithm and show the mechanism of adjusting property, time, and expertise weights, we first use a dataset designed for analyzing the effect of each ranking factor independently. We then show the ranking results of a real folksonomy site, with the ranking factors combined. Because the ground truth of a given dataset is not known when it comes to ranking, we inject simulated data whose ranking results can be predicted into the real dataset and compare the ranking results of our algorithm with that of a previous HITS-based algorithm. Our semantic ranking algorithm based on the concept of mutual interaction seems to be preferable to the HITS-based algorithm as a flexible folksonomy ranking framework. Some concrete points of difference are as follows. First, with the time concept applied to the property weights, our algorithm shows superior performance in lowering the scores of older data and raising the scores of newer data. Second, applying the time concept to the expertise weights, as well as to the property weights, our algorithm controls the conflicting influence of expertise weights and enhances overall consistency of time-valued ranking. The expertise weights of the previous study can act as an obstacle to the time-valued ranking because the number of followers increases as time goes on. Third, many new properties and classes can be included in our framework. The previous HITS-based algorithm, based on the voting notion, loses ground in the situation where the domain consists of more than two classes, or where other important properties, such as "sent through twitter" or "registered as a friend," are added to the domain. Forth, there is a big difference in the calculation time and memory use between the two kinds of algorithms. While the matrix multiplication of two matrices, has to be executed twice for the previous HITS-based algorithm, this is unnecessary with our algorithm. In our ranking framework, various folksonomy ranking policies can be expressed with the ranking factors combined and our approach can work, even if the folksonomy site is not implemented with Semantic Web languages. Above all, the time weight proposed in this paper will be applicable to various domains, including social media, where time value is considered important.

Semantic Multi-agents Framework for Ubiquitous Systems (유비쿼터스 시스템을 위한 시맨틱 다중 에이전트)

  • Choi Jung-Hwa;Park Young-Tack
    • Journal of KIISE:Software and Applications
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    • v.32 no.3
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    • pp.192-201
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    • 2005
  • For the past ten years, the goal of ubiquitous computing research has been the establishment of a new technology system with the aim 'Anytime, Anywhere, and Any form'. The needs for agent technology innovations such as ontology-based structure, ontology-based agent communication language, and multi-agents frameworks have been identified. This paper proposes a noble multi-agents architecture for ubiquitous systems. We suggest four major steps in the interaction between human and agents which enable ubiquitous agents to process by themselves to provide adaptive service to meet human's needs. First, we propose a semantic web technology to represent the association between information resources more explicitly Second, we construct a semantic ontology so that agents can recognize web contents.'Third, we propose a method to communicate between agents using OWL ontologies. Finally, we suggest a multi-agents structure based on the JADE of FIPA to analyze messages and get information. The semantic multi-agents framework proposed in this paper infers semantic situations using semantic web technology based on ontologies. A service provided is inferred differently according to user state because the multi-agents communicate by using OWL ontology language. Therefore, our system better infers context information than other without ontologies.