• 컴퓨터교육학회논문지
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• 제5권4호
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• pp.71-78
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• 2002

교육시스템에서 분산된 교육 정보를 검색, 공유하는 새로운 기술로 이동 에이전트가 주목을 받고 있다. 효율적인 검색을 수행하기 위해 많은 양의 컨텐츠를 전송받는 대신 검색을 수행하는 에이전트를 직접 서버에 전달하는 방식을 이용한다. 본 연구에서는 이동 에이전트를 이용하여 교육용 사이트에 분산적으로 존재하는 질의응답 게시판과 유즈넷의 자료를 검색, 공유하는 시스템의 모델을 제안한다. 제안된 시스템의 효율성을 살펴보기 위해 기존의 검색 모델과의 비교 실험을 하였으며 교육용 서버로 에이전트가 이동함에 따라 네트워크 트래픽이 감소됨을 볼 수 있었다 또한 이동 에이전트가 검색 위치로 이동 후 게시판과 유즈넷의 자료 변환을 위한 최적 검색 시간이 단축되었다.

• 전기학회논문지
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• 제65권6호
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• pp.1052-1059
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• 2016

Video-on-Demand(VoD) is one of the most popular media streaming which attracted many researchers' attention. VMesh is one of the most cited works in the field of the VoD system. VMesh is proposed to solve the problem of random seeking functionality. However, a large number of the DHT(Distributed Hash Table) searches in VMesh is sill the main problem which needs to be solved. In order to reduce the number of the DHT searches, the clustered segment index(CSI) scheme is proposed. In this scheme, the video segments are divided into clusters. The segment information of the video segments, which are clustered into the same cluster, are stored in the same clustered segment index that can be searched by using the hash key. Each peer also can request the required segments by using this clustered segment index. The experiment results show that the number of the DHT searches in the proposed scheme is less than that of VMesh even in case of peers leave and join the network or peers perform the fast forward/backward operations.

• Journal of Information Processing Systems
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• 제11권1호
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• pp.148-164
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• 2015

The use of mobile agents for collaborative processing in wireless sensor network has gained considerable attention. This is when mobile agents are used for data aggregation to exploit redundant and correlated data. The efficiency of agent-based data aggregation depends on the agent migration scheme. However, in general, most of the proposed schemes are centralized approach-based schemes where the sink node determines the migration paths for the agents before dispatching them in the sensor network. The main limitations with such schemes are that they need global network topology information for deriving the migration paths of the agents, which incurs additional communication overhead, since each node has a very limited communication range. In addition, a centralized approach does not provide fault tolerant and adaptive migration paths. In order to solve such problems, we have proposed a distributed approach-based scheme for determining the migration path of the agents where at each hop, the local information is used to decide the migration of the agents. In addition, we also propose a local repair mechanism for dealing with the faulty nodes. The simulation results show that the proposed scheme performs better than existing schemes in the presence of faulty nodes within the networks, and manages to report the aggregated data to the sink faster.

• 한국의류학회지
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• 제26권11호
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• pp.1527-1576
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• 2002

Quick Response based Mass-Customization can be produced and distributed customized goods and services on mass basis in apparel e-business. Because consumers can: t touch and feel the apparel products in e-business, they tend to have the negative buying behavior. The purpose of this study is to investigate the differences of consumer's texture sensibility of apparel products based on marketing channels (on-line/off-line). Two types of questionnaires for on-line and of f-line were used to assess consumer sensibility on apparel fabric. The 8 swatches were selected in regard to the previous literatures. 205 questionnaires for each type (on-line/off-line) were distributed. Statistical devices were t-test, mean and standard deviation with SPSS10.0. The result of this study was showed that there were partially significant differences on consumers' texture sensibility on apparel products between on-line and off-line. Under on-line environment, consumers perceived corduroy as warm, strong, and sandy. taffeta as warm, sandy, and glossy, denim as sandy, and warm, organza as sandy, and thin, satin as sandy, dense, and modern, chiffon as sandy, and flat, velvet as warm, and soft, single jersey as warm, soft, and comfortable. Therefore, apparel firms cooperating based Mass-Customization in e-business have to pay attention to the differences on consumers’ texture sensibility of on-line apparel products from those of off-line.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 춘계학술대회 논문집
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• pp.105-110
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• 2009

Distributed Generation (DG) is predicted to play a important role in electric power system in the near future. insertion of DG system into existing distribution network has great impact on real-time system operation and planning. It is widely accepted that micro turbine generation (MTG) systems are currently attracting lot of attention to meet customers need in the distributed power generation market In order to investigate the performance of MT generation systems, their efficient modeling is required. This paper presents the modeling and simulation of a MT generation system suitable for grid-connected operation. The system comprises of a permanent magnet synchronous generator driven by a MT. A brief description of the overall system is given, and mathematical models for the MT and permanent magnet synchronous generator are presented. Also, the use of Power electronics in conditioning the power output of the generating system is demonstrated. Simulation studies with MATLAB/Simulink have been carried out in grid-connected operation mode of a DG system. The control strategies for grid connected operation mode of DG system is also presented.

• 한국정보처리학회논문지
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• 제6권7호
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• pp.1770-1776
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• 1999

최근 몇 년 동안 이동 에이전트(Mobile Agent) 기술은 분산 처리 시스템(Distributed Processing System)의 새로운 패러다임(Paradigm)으로 많은 관심이 되어왔다. 이동 에이전트는 통신망 노드에서 노드로 이주 가능한 자율적인 객체이다. 그러나, 통신망에 연동된 호스트(host)나 노드 결손 등으로 인해 이동 에이전트는 계속 처리할 수 있는 다른 노드들이 있을 지라도 무한 대기하거나 파괴될 수 있다. 이를 위해서, 본 논문은 이동 에이전트의 이주를 보장하기 위한 경로 재조정과 후위복구 기법을 통한 효율적인 이주 정책을 제안한다. 제안된 이주 정책은 가능한 한 자율적으로 이동 에이전트의 이주 신뢰를 제공하고, 자바(Java) 언어로 개발된 이동 시스템 모델인 MOS에서 이를 구현한다.

• 유통과학연구
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• 제20권8호
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• pp.1-8
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• 2022

Purpose: Research on attracting foreign direct investment (FDI) plays an important role in helping provinces attract more FDI projects. However, with local competition, FDI enterprises also have to consider their investment. This study evaluates the provincial competitiveness to attract FDI in Thai Nguyen province, a province of Vietnam. In which provincial distribution of competitiveness is measured through nine indicators. Research design, data, and methodology: The study collects data (FDI and the provincial competitiveness index) from 2006 to 2020. The study uses Autoregressive Distributed Lag (ARDL) to text the impact of distribution of competitivenes on foreign direct investment. With time-series, the ARDL is suitable for data analysis. Results: The regression results indicate that the competition index of market entry and informal costs negatively impact attracting FDI into the province; The human resource training quality index has a positive effect on FDI. The results show that FDI enterprises pay much attention to business establishment procedures, hidden costs, and quality of human resources in the province. Conclusions: At the same time, in terms of practice, the results of this study, the authors also offer solutions to help improve the ability to attract FDI into Thai Nguyen province. The significant provincial competitiveness indicators should be taken into account for improvement first.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권7호
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• pp.2286-2304
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• 2022

Blockchain is a distributed ledger that combines technologies such as cryptography, consensus mechanism, peer-to-peer transmission, and time stamping. The rapid development of blockchain has attracted attention from all walks of life, but storage scalability issues have hindered the application of blockchain. In this paper, a scalable blockchain storage model based on Distributed Hash Table (DHT) and the InterPlanetary File System (IPFS) was proposed. This paper introduces the current research status of the scalable blockchain storage model, as well as the basic principles of DHT and the InterPlanetary File System. The model construction and workflow are explained in detail. At the same time, the DHT network construction mechanism, block heat identification mechanism, new node initialization mechanism, and block data read and write mechanism in the model are described in detail. Experimental results show that this model can reduce the storage burden of nodes, and at the same time, the blockchain network can accommodate more local blocks under the same block height.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제30권3호
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• pp.121-126
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• 2019

Objectives: Awareness of attention-deficit/hyperactivity disorder (ADHD) in adults has significantly increased; however, clinical data specific to the Korean population are insufficient. Clinical experience of ADHD may differ based on whether psychiatrists have received pediatric psychiatry-specific training. In order to prepare a practice parameter for adult ADHD patients in Korea, we examined questionnaire data to observe how pediatric psychiatry training could affect clinical practice for adults with ADHD. Methods: A questionnaire about the diagnosis and treatment process was distributed to both general psychiatrists (GPsy) and child and adolescent psychiatrists (CAP) at the summer and winter workshop meetings of Korean Academy of Child and Adolescent Psychiatry. Results: In total, 142 psychiatrists participated in the survey (86 GPsy, 56 CAP). GPsy and CAP preferred pharmacotherapy (GPsy 82.40%, CAP 64.30%) as the primary treatment option and answered that the clinical psychiatric interview is the most necessary step in diagnostic assessment (GPsy 22.16%, CAP 19.00%). The GPsy responded with an optimal and average treatment duration that was shorter than that reported by CAP. Conclusion: Identification of the initial presenting symptom as the correct diagnosis and the optimal duration of pharmacotherapy differed between GPsy and CAP in practice, whereas concepts in diagnosis and treatment of ADHD in adults were similar for both groups. These results suggest the urgent need for the Continuing Medical Education program for psychiatrists treating adults with ADHD.

• The Korean Journal of Ecology
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• 제7권3호
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• pp.132-157
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• 1983

This study was performed to investigated the flora and vegetation of Kokum-do island from July 1982 thru December 1983; and the findings hereof are summarized as follows: The flora investigated thereform comprises 737 species whih are classified into 128 families, 466 genera, 651 species, 79 varieties and 7 formae; and those which are worthy of close attention among the same include such endemic species of Korea as Celtis choseniana, Corylopsis coreana, Carpinus tschonoskii var. eximia and Tricyrtis dilatata, and a few plants, to be distributed in the north, such as Lilium distichum, Girardinia cuspidata and Orostachys sikokianus. Now that the said island belongs to the warm temperate zone, the distribution thereof consists of 120 species of evergreen plants including 74 species of evergreen broadleaf trees. The rich distribution of evergreen broadleaf trees in the island is thanks to the plantation thereof by the public organizations for scenic beauty. The destruction of flora in this island was caused by felling, fire nization and other human activities around 1940, and in particular, has been correlated with the population densiity of Yonhong-do, Sanghwa-do, and Hahwado islets; and that of top soil and ground vegetation in he quarry area of Ojon-ri town resulted from the collection of natural rocks an stones. It is evaluated as necessary that such evergreen broadleaf trees as Castanopsis cuspidata var. thunbergii, Machillus thunbergii and Ligustrum japonicum of Hyongje-do. Chun-do, Tok-do, Taech'wi-do, and Soch'wi-do islets, andPhyllostachys bambusoides, Caesalpinia japonica and Albizzia julibirssin of Kokum-do island, and Machillus thunbergii of Hongryon-ri town be under protection. The average DGN of the whole archipelago proves to be 5.84, which shows the tendency of the inverse proportion to the number of resident population per unit area. The pteridophyta distributed in this island comprises 39 species, and the coefficient of cryptogam as to the destruction of vegetation shows a high value of 1.4 which is regarded as indicating the diversified distribution of pteridophyta, forestbed shade plants under the forestbeds of some wellpreserved lots of this island. The naturalized plants, distributed in this island, were found out comprising a total of 23 species, and the Urbanization Index(UI) as to the destruction degree of natural vegetatioin shows a low value of 20.9.