• Title/Summary/Keyword: ways of linking

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Evaluating Changes in Blue Carbon Storage by Analyzing Tidal Flat Areas Using Multi-Temporal Satellite Data in the Nakdong River Estuary, South Korea (다중시기 위성자료 기반 낙동강 하구 지역 갯벌 면적 분석을 통한 블루카본 저장량 변화 평가)

  • Minju Kim;Jeongwoo Park;Chang-Uk Hyun
    • Korean Journal of Remote Sensing
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    • v.40 no.2
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    • pp.191-202
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    • 2024
  • Global warming is causing abnormal climates worldwide due to the increase in greenhouse gas concentrations in the atmosphere, negatively affecting ecosystems and humanity. In response, various countries are attempting to reduce greenhouse gas emissions in numerous ways, and interest in blue carbon, carbon absorbed by coastal ecosystems, is increasing. Known to absorb carbon up to 50 times faster than green carbon, blue carbon plays a vital role in responding to climate change. Particularly, the tidal flats of South Korea, one of the world's five largest tidal flats, are valued for their rich biodiversity and exceptional carbon absorption capabilities. While previous studies on blue carbon have focused on the carbon storage and annual carbon absorption rates of tidal flats, there is a lack of research linking tidal flat area changes detected using satellite data to carbon storage. This study applied the direct difference water index to high-resolution satellite data from PlanetScope and RapidEye to analyze the area and changes of the Nakdong River estuary tidal flats over six periods between 2013 and 2023, estimating the carbon storage for each period. The analysis showed that excluding the period in 2013 with a different tidal condition, the tidal flat area changed by up to approximately 5.4% annually, ranging from about 9.38 km2 (in 2022) to about 9.89 km2 (in 2021), with carbon storage estimated between approximately 30,230.0 Mg C and 31,893.7 Mg C.

A Study on the Improvement Plan for Enhancing Utilization of Defense Critical Technologies (국방 핵심기술 활용성 증대를 위한 개선 방안 연구)

  • Cho, Il-Ryun;Kim, Chan-Soo;Noh, Sang-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.6
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    • pp.120-125
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    • 2018
  • Various security threats, such as North Korea's nuclear tests and intercontinental ballistic missile developments, are becoming issues. Considering the current security situation in South Korea, proper selection of weapons and efficient defense acquisition systems are essential. In this paper, we conduct a survey and analysis of the defense core technology necessary for the development of weapons systems, and review whether current defense research and development is carried out efficiently. A theoretical study was conducted on ways to enhance the linkage between defense core technology and weapons systems development. As a result of the study, the necessity for development of weapons systems and the linking of defense core technology planning with the need for institutional improvement in enhanced utilization of defense core technology were derived. We propose a method for a long-term weapons systems concept plan that integrates defense core technology planning with forces planning and pre-project research programs to improve planning efficiency.

Study on the Air Insulation Design Guideline for ±500 kV Double Bipole Transmission Line with Metallic Return Conductor (도체귀로형 ±500 kV Double Bipole 송전선로 공기절연에 관한 연구)

  • Shin, Kooyong;Kwon, Gumin;Song, Seongwhan;Woo, Jungwook
    • KEPCO Journal on Electric Power and Energy
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    • v.5 no.3
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    • pp.141-147
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    • 2019
  • Recently, the biggest issue in the electricity industry is the increase in renewable energy, and various technologies are being developed to ensure the capacity of the power system. In addition, super-grids linking power systems are being pushed to utilize eco-friendly energy between countries and regions worldwide. The HVDC transmission technology is required to link the power network between regions with different characteristics of the power system such as frequency and voltage. Until now, Korea has applied HVDC transmission technology that connects mainland and Jeju Island with submarine cables. But, the HVDC transmission technology is still developing for long-distance high-capacity power transmission from power parks on the east coast to load-tight areas near the metropolitan area. Considering the high population density and mountainous domestic environment, it is pushing for commercialization of the design technology of the ${\pm}500kV$ Double Bipole with metallic return wire transmission line to transmit large-scale power of 8 GW using minimal right of ways. In this paper, the insulation characteristics were studied for the design of double-bipole transmission tower with metallic return wire, which is the first time in the world. And the air insulation characteristics resistant to the various overvoltage phenomena occurring on transmission lines were verified through a full-scale impulse voltage test.

The Effects of A Cognitive-Behavioral Anger Control Training on Anger Control Ability and Peer Relationships of Children (인지행동적 분노조절 훈련이 아동의 분노조절능력과 교우관계에 미치는 효과)

  • Kim, Mi-Ra;Lee, Young-Man
    • The Korean Journal of Elementary Counseling
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    • v.7 no.2
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    • pp.101-115
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    • 2008
  • The purposes of this study were to consist an anger control program in order to help children confirm and modify their cognitive errors in peer anger-provoking situations(Lee Mi-gyeong, 2006), that and to examine the effects of this program on anger-provoking experience, anger controllability and peer relationship. The cognitive-behavioral anger control program was consisted of 16 sessions. The focus of the program were placed on perceiving angry feelings, confirming automatic thinking and cognitive errors and acquiring how to correct the cognitive errors(1st-10th sessions), and checking cognitive errors in 13 anger-provoking situations and practicing way to correct the errors(11th-15th sessions). To examine the effects of the program, 10 children who had a lot of anger-provoking experiences, and were poor at anger control and faced difficulties with peer relationship were selected. The cognitive-behavioral anger control program was implemented for eight weeks, twice a week, 40 minutes each. The collected data were analysed by the ANOVA method using the SPSS and Kwakstat(Kwak Ho-wan, 1993). What cognitive errors children made and how they modified the errors during the program were checked. The findings of the study were as follows: The cognitive-behavioral anger control program served to cut down on the anger-provoking experiences, to improve their anger controllability, to boost their peer relationship, and that effect lasted till six weeks later. And the cognitive errors they made during the program were in the order as follows: stating the oughtness of their behavior, followed by naming, seeing everything in black and white, emotional judgment, mind reading, linking the situation to themselves, overgeneralizing, and hasty conclusion. The ways to correct the cognitive errors were in the order as follows: putting oneself in another's place, explaining in a different manner, looking for proof, thinking of it is so difficult to indure, thinging of there is moral to it, and thinking of how angry after passing time.

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A Ranking Algorithm for Semantic Web Resources: A Class-oriented Approach (시맨틱 웹 자원의 랭킹을 위한 알고리즘: 클래스중심 접근방법)

  • Rho, Sang-Kyu;Park, Hyun-Jung;Park, Jin-Soo
    • Asia pacific journal of information systems
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    • v.17 no.4
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    • pp.31-59
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    • 2007
  • We frequently use search engines to find relevant information in the Web but still end up with too much information. In order to solve this problem of information overload, ranking algorithms have been applied to various domains. As more information will be available in the future, effectively and efficiently ranking search results will become more critical. In this paper, we propose a ranking algorithm for the Semantic Web resources, specifically RDF resources. Traditionally, the importance of a particular Web page is estimated based on the number of key words found in the page, which is subject to manipulation. In contrast, link analysis methods such as Google's PageRank capitalize on the information which is inherent in the link structure of the Web graph. PageRank considers a certain page highly important if it is referred to by many other pages. The degree of the importance also increases if the importance of the referring pages is high. Kleinberg's algorithm is another link-structure based ranking algorithm for Web pages. Unlike PageRank, Kleinberg's algorithm utilizes two kinds of scores: the authority score and the hub score. If a page has a high authority score, it is an authority on a given topic and many pages refer to it. A page with a high hub score links to many authoritative pages. As mentioned above, the link-structure based ranking method has been playing an essential role in World Wide Web(WWW), and nowadays, many people recognize the effectiveness and efficiency of it. On the other hand, as Resource Description Framework(RDF) data model forms the foundation of the Semantic Web, any information in the Semantic Web can be expressed with RDF graph, making the ranking algorithm for RDF knowledge bases greatly important. The RDF graph consists of nodes and directional links similar to the Web graph. As a result, the link-structure based ranking method seems to be highly applicable to ranking the Semantic Web resources. However, the information space of the Semantic Web is more complex than that of WWW. For instance, WWW can be considered as one huge class, i.e., a collection of Web pages, which has only a recursive property, i.e., a 'refers to' property corresponding to the hyperlinks. However, the Semantic Web encompasses various kinds of classes and properties, and consequently, ranking methods used in WWW should be modified to reflect the complexity of the information space in the Semantic Web. Previous research addressed the ranking problem of query results retrieved from RDF knowledge bases. Mukherjea and Bamba modified Kleinberg's algorithm in order to apply their algorithm to rank the Semantic Web resources. They defined the objectivity score and the subjectivity score of a resource, which correspond to the authority score and the hub score of Kleinberg's, respectively. They concentrated on the diversity of properties and introduced property weights to control the influence of a resource on another resource depending on the characteristic of the property linking the two resources. A node with a high objectivity score becomes the object of many RDF triples, and a node with a high subjectivity score becomes the subject of many RDF triples. They developed several kinds of Semantic Web systems in order to validate their technique and showed some experimental results verifying the applicability of their method to the Semantic Web. Despite their efforts, however, there remained some limitations which they reported in their paper. First, their algorithm is useful only when a Semantic Web system represents most of the knowledge pertaining to a certain domain. In other words, the ratio of links to nodes should be high, or overall resources should be described in detail, to a certain degree for their algorithm to properly work. Second, a Tightly-Knit Community(TKC) effect, the phenomenon that pages which are less important but yet densely connected have higher scores than the ones that are more important but sparsely connected, remains as problematic. Third, a resource may have a high score, not because it is actually important, but simply because it is very common and as a consequence it has many links pointing to it. In this paper, we examine such ranking problems from a novel perspective and propose a new algorithm which can solve the problems under the previous studies. Our proposed method is based on a class-oriented approach. In contrast to the predicate-oriented approach entertained by the previous research, a user, under our approach, determines the weights of a property by comparing its relative significance to the other properties when evaluating the importance of resources in a specific class. This approach stems from the idea that most queries are supposed to find resources belonging to the same class in the Semantic Web, which consists of many heterogeneous classes in RDF Schema. This approach closely reflects the way that people, in the real world, evaluate something, and will turn out to be superior to the predicate-oriented approach for the Semantic Web. Our proposed algorithm can resolve the TKC(Tightly Knit Community) effect, and further can shed lights on other limitations posed by the previous research. In addition, we propose two ways to incorporate data-type properties which have not been employed even in the case when they have some significance on the resource importance. We designed an experiment to show the effectiveness of our proposed algorithm and the validity of ranking results, which was not tried ever in previous research. We also conducted a comprehensive mathematical analysis, which was overlooked in previous research. The mathematical analysis enabled us to simplify the calculation procedure. Finally, we summarize our experimental results and discuss further research issues.

Methods for Integration of Documents using Hierarchical Structure based on the Formal Concept Analysis (FCA 기반 계층적 구조를 이용한 문서 통합 기법)

  • Kim, Tae-Hwan;Jeon, Ho-Cheol;Choi, Joong-Min
    • Journal of Intelligence and Information Systems
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    • v.17 no.3
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    • pp.63-77
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    • 2011
  • The World Wide Web is a very large distributed digital information space. From its origins in 1991, the web has grown to encompass diverse information resources as personal home pasges, online digital libraries and virtual museums. Some estimates suggest that the web currently includes over 500 billion pages in the deep web. The ability to search and retrieve information from the web efficiently and effectively is an enabling technology for realizing its full potential. With powerful workstations and parallel processing technology, efficiency is not a bottleneck. In fact, some existing search tools sift through gigabyte.syze precompiled web indexes in a fraction of a second. But retrieval effectiveness is a different matter. Current search tools retrieve too many documents, of which only a small fraction are relevant to the user query. Furthermore, the most relevant documents do not nessarily appear at the top of the query output order. Also, current search tools can not retrieve the documents related with retrieved document from gigantic amount of documents. The most important problem for lots of current searching systems is to increase the quality of search. It means to provide related documents or decrease the number of unrelated documents as low as possible in the results of search. For this problem, CiteSeer proposed the ACI (Autonomous Citation Indexing) of the articles on the World Wide Web. A "citation index" indexes the links between articles that researchers make when they cite other articles. Citation indexes are very useful for a number of purposes, including literature search and analysis of the academic literature. For details of this work, references contained in academic articles are used to give credit to previous work in the literature and provide a link between the "citing" and "cited" articles. A citation index indexes the citations that an article makes, linking the articleswith the cited works. Citation indexes were originally designed mainly for information retrieval. The citation links allow navigating the literature in unique ways. Papers can be located independent of language, and words in thetitle, keywords or document. A citation index allows navigation backward in time (the list of cited articles) and forwardin time (which subsequent articles cite the current article?) But CiteSeer can not indexes the links between articles that researchers doesn't make. Because it indexes the links between articles that only researchers make when they cite other articles. Also, CiteSeer is not easy to scalability. Because CiteSeer can not indexes the links between articles that researchers doesn't make. All these problems make us orient for designing more effective search system. This paper shows a method that extracts subject and predicate per each sentence in documents. A document will be changed into the tabular form that extracted predicate checked value of possible subject and object. We make a hierarchical graph of a document using the table and then integrate graphs of documents. The graph of entire documents calculates the area of document as compared with integrated documents. We mark relation among the documents as compared with the area of documents. Also it proposes a method for structural integration of documents that retrieves documents from the graph. It makes that the user can find information easier. We compared the performance of the proposed approaches with lucene search engine using the formulas for ranking. As a result, the F.measure is about 60% and it is better as about 15%.