• Journal of Korean Society of Steel Construction
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• v.18 no.2
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• pp.213-223
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• 2006

Conventional truss optimization approaches, while often sophisticated and computationally intensive, have been applied to simple, minimum weight-cost models. These approaches do not perform well when applied to real-world trusses, which have costmodels that are complex and which often involve multiple objectives. Thus, this paper describes the optimization strategies that a clustering technique, which identifies members that are likely to have the same product type, uses for the optimal design of truss structures with real- world cost functions that consider the costs on the weight of the truss, the number of products in the design, the number of joints in the structures, and the costs required in the site.At first, the clustering technique is applied to identify the members and to generate a proper initial solution. A simple taboo search technique is then used, which attempts to generate the optimal solution by starting with the solution from the previous technique. For example, the proposed approach is a plied to a typical problem and to a problem similar to relative performances. The results show that this algorithm generates not only better-quality solutions but also more efficient ones

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.3
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• pp.157-165
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• 2019

Recently, large and small earthquakes have occurred in the Korean peninsula. In this sense, Korea is no longer considered as an earthquake free zone. Especially, it is necessary to respond quickly to earthquake tsunami which may be caused by the influence of neighboring countries with large earthquakes. Since the occurrence of tsunamis can cause great casualties, it is very important to allocate the location of the shelter in case of an earthquake. Although many researches on shelter allocation have been conducted in various ways, but most of them have been analyzed based on administrative district resident data, resulting in a lack of reality. In this study, floating population data were used to reflect reality in case of emergency situations, and genetic algorithm, which produce good results among the heuristic algorithms, was used to select shelter locations. The number of evacuees was used as a objective function of genetic algorithm and the optimal solution was found through selection, crossover and mutation. As a result of the research on Busan Haeundae-Gu, selected as a research area, allocating eight shelters was the most efficient. The location of the new shelters was selected not only in residential areas but also in major tourist areas whose results can not be derived from administrative district resident data alone, and the importance of utilizing the floating population data was confirmed through this study.

• Journal of Korean Society of Archives and Records Management
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• v.21 no.3
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• pp.187-215
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• 2021

Archives should provide a web-based archival information service with good usability based on the understanding of users' needs. Thus, this study analyzed the usability of the National Archives of Korea (NAK) website's search service through expert and usability evaluations for various users and suggested improvement plans. A literature review, heuristic evaluation, one of the usability expert evaluation methods, and usability evaluation for users were performed. As a result of expert evaluation, the severity rating for the usability problem was highest regarding a match between the system and real world and the lowest in error prevention. In the usability evaluation, it was assumed that the user's background and whether the website's help was provided is associated with usability. Usability evaluation was conducted for 22 participants, including those majoring in records management, web/application developers, and people without such backgrounds. Furthermore, a presurvey, a five-second test, and search tasks were conducted in a row. The analysis based on usability components in ISO 9241-11: 2018, i.e., effectiveness, efficiency, and satisfaction, showed that web/application developers had the highest search effectiveness, and those majoring in records management showed high effectiveness only in the search for archival content services. Background factors did not affect efficiency, and the more familiar with the finding aids, the better the efficiency. Moreover, providing the website's help was found to be positively associated with effectiveness and satisfaction. This study suggests that the NAK website will offer a user-friendly interface and search function, expand help support, and display a consistent web interface.

• The Journal of the Acoustical Society of Korea
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• v.43 no.2
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• pp.214-224
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• 2024

Sonobuoys are disposable devices that utilize sound waves for information gathering, detecting engine noises, and capturing various acoustic characteristics. They play a crucial role in accurately detecting underwater targets, making them effective detection systems in anti-submarine warfare. Existing sonobuoy deployment methods in multistatic systems often rely on fixed patterns or heuristic-based rules, lacking efficiency in terms of the number of sonobuoys deployed and operational time due to the unpredictable mobility of the underwater targets. Thus, this paper proposes an optimal sonobuoy placement strategy for Unmanned Aerial Vehicles (UAVs) to overcome the limitations of conventional sonobuoy deployment methods. The proposed approach utilizes reinforcement learning in a simulation-based experimental environment that considers the movements of the underwater targets. The Unity ML-Agents framework is employed, and the Proximal Policy Optimization (PPO) algorithm is utilized for UAV learning in a virtual operational environment with real-time interactions. The reward function is designed to consider the number of sonobuoys deployed and the cost associated with sound sources and receivers, enabling effective learning. The proposed reinforcement learning-based deployment strategy compared to the conventional sonobuoy deployment methods in the same experimental environment demonstrates superior performance in terms of detection success rate, deployed sonobuoy count, and operational time.

• The Journal of Korean Philosophical History
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• no.32
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• pp.395-432
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• 2011

The purpose of this study is (i) to explore arguments of post-kohlbergian approach in moral psychology and; (ii) to analyze Blasi's and Lapsley's positions regarding the relationship between moral philosophy and psychology in terms of reflective reasoning and; (ⅲ) to suggest their's implication concerning the future development of moral identity theory. Moral identity theory has emerged as an alternative approach of the Kohlberg's moral development theory. Theorists of moral identity theory commonly criticize Kohlberg's theory as a philosophical psychology and insist the autonomy of moral psychology. However, one can find different positions within this trend, especially concerning he meaning and role of the reflection in moral functioning. Blasi emphasizes the importance of the reflective reasoning of moral agent, while Lapsley supports moral automacy contrary to Kohlberg's phenomenalism. Although Blasi had been negative about building moral psychology based on the moral philosophy, he has articulated the moral identity theory based on the concept of free will by Frankfurt. However, recently he criticizes intuitionist theory of Haidit and suggests the notion of the moral agent with the skill of reflective reasoning, or post-conventional thinking in Kohlberg's terms. Blasi's perspective of moral identity has two version. The one emphasizes the moral understanding which means strong evaluation, while the other refers to reasoning with weak evaluation. This leads to an inevitable inner contradiction within his theory of moral identity. Lapsley considers moral identity as a heuristic idea and suggests moral chronic as a new model of moral identity. This model is based on the social cognitive theory. His social cognitive model of moral personality provides the account for implicit, tacit, and automatic of moral functioning, while reflecting the core of moral identity. Lapsley suggests that moral function involves conscious and unconscious processes. The former occurs in normal situations of life, while the latter in rare and unusual situations. He does not highlight reasoning in moral functioning as Blasi do. In consequence, I will argue the notion of the moral agent with the skill of reflective reasoning, or post conventional thinking in Kohlberg's terms in the moral functioning like Gibbs and Turiel positions in the Journal of Moral Education' s 2008 special issue. Moral philosophy and psychology should be in complementary relations. It means we explore not only more interdisciplinary researches on the moral functioning, but also researches based on the moral philosophy.