• Journal of the Korea Society of Computer and Information
• /
• v.16 no.6
• /
• pp.179-186
• /
• 2011

This paper suggests the minimum number of vertex guards algorithm. Given n rooms, the exact number of minimum vertex guards is proposed. However, only approximation algorithms are presented about the maximum number of vertex guards for polygon and orthogonal polygon without or with holes. Fisk suggests the maximum number of vertex guards for polygon with n vertices as follows. Firstly, you can triangulate with n-2 triangles. Secondly, 3-chromatic vertex coloring of every triangulation of a polygon. Thirdly, place guards at the vertices which have the minority color. This paper presents the minimum number of vertex guards using dominating set. Firstly, you can obtain the visibility graph which is connected all edges if two vertices can be visible each other. Secondly, you can obtain dominating set from visibility graph or visibility matrix. This algorithm applies various art galley problems. As a results, the proposed algorithm is simple and can be obtain the minimum number of vertex guards.

• The KIPS Transactions:PartA
• /
• v.15A no.5
• /
• pp.295-300
• /
• 2008

In this paper, we consider a characterization of a Guard Sufficiency Set(GSS) in the hierarchy of simple polygons. we propose the diagonals of a arbitrary triangulation of a polygon as a GSS when guards see the diagonals with completely visibility and both sides of the diagonal. we show that this can be a GSS in convex polygons, unimodal polygons, spiral polygons but this can not be a GSS in star-shaped polygons, monotone polygons, completely external visible polygons.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.12 no.3
• /
• pp.63-69
• /
• 2012

Given art gallery P with n vertices, the maximum (sufficient) number of mobile guards is${\lfloor}n/4{\rfloor}$ for simple polygon and${\lfloor}(3n+4)/16{\rfloor}$ for simple orthogonal polygon. However, there is no polynomial time algorithm for minimum number of mobile guards. This paper suggests polynomial time algorithm for the minimum number of mobile guards. Firstly, we obtain the visibility graph which is connected all edges if two vertices can be visible each other. Secondly, we select vertex u with ${\Delta}(G)$ and v with ${\Delta}(G)$ in $N_G(u)$ and delete visible edges from u,v and incident edges. Thirdly, we select $w_i$ in partial graphs and select edges that is the position of mobile guards. This algorithm applies various art galley problems with simple polygons and orthogonal polygons art gallery. As a results, the running time of proposed algorithm is linear time complexity and can be obtain the minimum number of mobile guards.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2013.05a
• /
• pp.1049-1052
• /
• 2013

저자들은 1980 년대 후반부터 역사학적 논쟁들을 통계적 수학적 방법을 이용하여 분석해보고자 하는 시도들을 하여 왔다. 최근에는 역사학의 논쟁점 중이 하나인 화랑세기의 진위 여부를 분석하기 위한 일련의 연구를 시도하였다. 이러한 일련의 시도의 일환으로 이 연구는 기획되었다. 이 글에서는 일본의 고대 기년 추정 방법을 참고하면서 세대 평균치와 재위 평균치의 추정이라는 방법을 통하여 "삼국사기" 초기 기년 문제에 대한 해명을 시도해 보고자 한다. 종래에는 세대 평균치라는 개념을 사용하지 않아서 편차가 심한 왕별 재위기간 평균치만 사용하여 재위기간 추정의 오차가 컸다. 또한 여러 가지 추론들이 주관적인 판단에 의지한 부분이 많아서 폭넓은 지지를 얻지 못한 경우가 많았다. 따라서 세대 평균치와 재위 평균치는 반드시 일치하지 않는다는 점을 분명히 하는 한편, 양자를 결합한 추정 방안을 마련해 볼 것이다.

• 한국정보교육학회:학술대회논문집
• /
• 2021.08a
• /
• pp.77-84
• /
• 2021

The purpose of this study is to propose AI maker coding education as a way to improve computational thinking(CT), which is an essential competence for problem-solving capability in modern society, and to analyze the effectiveness of this education on improving CT in elementary school students. For the research, 5 students from 4th graders and 5 students from 6th graders were recruited, and AI maker coding education was planned in 8 sessions to form classes from basic block coding and maker education to real-life problem solving. To analyze the effectiveness of AI maker coding education, pre- and post-CT examinations were performed. The test results confirmed that AI maker coding education had a significant effect on "abstraction", "algorithm", and "data processing" in the five CT components, and confirmed that there was no correlation in "problem resolution" and "automation". Overall, the average score of all students increased, and the deviation between students decreased, confirming that AI maker coding education was effective in improving CT.

• Journal of The Korean Association of Information Education
• /
• v.25 no.5
• /
• pp.779-790
• /
• 2021

This study analyzed the effect of AI maker coding education on improving students' computational thinking. The subjects of the study were 10 students at H Elementary School in Ansan, and a total of 8 AI maker coding education using the Instructional Model for Maker Education based on SW Coding was applied to students to find out the degree of improvement of computational thinking. Students who participated in the class performed a process of solving real-life problems through coding and making activities, measured the degree of improvement in computing thinking before and after education through a computing thinking test paper, and observed students' thinking processes related to computing thinking components through interviews. As a result, it was confirmed that the average score of all students' computational thinking skills was improved, and the deviation of scores between students decreased. Through the interview, it was found that students actively utilize their thinking skills related to computational thinking skills in the problem-solving process. Through this, it was confirmed that AI maker coding education can have a positive effect on improving students' computing thinking skills.

• Journal of KIISE:Computer Systems and Theory
• /
• v.31 no.1_2
• /
• pp.102-111
• /
• 2004

The visibility polygon of a simple polygon P is the set of points which are visible from a visibility source in P such as a point or an edge. Since a visibility polygon is the set of points, the set operations such as intersection, union, or difference can be executed on them. The intersection (resp. union) of two visibility polygons is the set of points which are visible from both (resp. either) of the corresponding two visibility sources. The difference of two visibility polygons is the set of points which are visible from only a visibility source. Previously, the best known algorithm for the set operations of two polygons with total n vertices takes O(nlogn ＋ k) time, where k is the output size. In this paper, we present O(n) time algorithms for computing the intersection, the union, and the difference of given two visibility polygons, which are optimal.

• Korean Journal of Construction Engineering and Management
• /
• v.14 no.1
• /
• pp.115-123
• /
• 2013

Changes have occurred in the professional capabilities of the construction project managers after the global financial crisis. As representatives of construction companies and projects, construction project managers have full responsibility over a construction project. Throughout its life cycle, from design through construction to completion, the business capabilities of such managers are regarded as critical elements in the changes in the country's construction economy. Therefore, this study aimed to determine the main capabilities of current construction project managers, and to analysis of its competitiveness using Important-Performance Analysis(IPA). The results of IPA were as follows; (1)capability to win new contracts and capability to collect information of new project are needed for external relation competitiveness, (2)gerentocratic management mind-set and active breakthrough are needed for internal project management competitiveness, and (3)capability to predict issues and self-improvement are needed for self discipline competitiveness. However, this work is still considered to provide the basic data that can help Korean construction companies who plan to educate the project manager's strengthen their medium and long-term capabilities.

• Korean Association of Arts Management
• /
• no.51
• /
• pp.191-219
• /
• 2019

Adoption of applicable law for the international trade of artworks is closely related to the results of lawsuits. Recently, starting with New York, the hub of the international artworks market, a modern, mixed-law is gradually being adopted more. It is difficult to designate an applicable law of an international trade of artworks through private laws regulations of relevant countries, and the public laws regulations must also be considered in relation to individual benefits and the public benefits to the relevant countries. With regards to the foreign relations issues, Korea's private international law embraces a so-called public order theory, and according to the Section 7 of the Act on the Private International Law and its enactment history, the compulsory provision, which seems appropriate for application to the corresponding matter, applies without regards to the selection of the applicable law. The Civil Act of Korea acknowledges bona fide acquisition of a cultural asset, in principle, if the Cultural Heritage Protection Act is not applicable. Moreover, a lost artwork is also a subject of bona fide acquisition; however, if the relevant artwork is either stolen or lost, the original owner has the right to demand the return of that artwork within 2 years of being stolen or lost according to the Section 250 of the Civil Act. Also, if the buyer purchased from a distributor specializing in the artworks, such as auction, open market or gallery, the buyer could request a compensation of the purchase price from the original owner, and if the buyer purchased through a private transaction, the buyer cannot demand a compensation of the purchase price and must return the artwork.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.2
• /
• pp.279-292
• /
• 2018

Unlike the global art market which experienced rapid recovery from the impacts of the Global Financial Crisis in 2008, the Korean art market has not yet fully recovered. The gallery-oriented distribution system, vulnerable primary art market functions, and the market structure centered on a small number of collectors make it difficult for young and medium artists to enter the market and, as a result, deepen the economic polarization of artists. In addition, the high price of art works limits market participation by restricting the general public. This study began with the idea that the interest of the public in the art market as well as their participation in the market are urgent. To this end, we noted that public awareness of art transactions can be a starting point for improving the constitution of the fragile art market, focusing on the 'Artist-centered Art Fair' rather than existing art fairs. To examine the contribution of such an art fair to the popularization of the art market, we analyzed the case of the 'Visual Artist Market (VAM)' project of the Korea Arts Management Service. Results found that the 'Artist-centered Art Fair' focuses on providing opportunities for market entry to young and medium artists rather than on the interests of distributors, and promotes the popularization of the art market by promoting low-priced works to the general public. Also, the 'Artist-centered Art Fair' seems to play a primary role in the public sector to foster solid groups of artists as well as to establish healty distribution networks of Korean Art market. However, in the long run, it is necessary to promote sustainable development of the 'Artist-centered Art Fair' through indirect support, such as the provision of a publicity platform or consumer finance support, rather than direct support.