• 한국통신학회논문지
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• 제34권12B호
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• pp.1329-1335
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• 2009

본 논문에서는 무선 인체 통신 네트워크에서 응급 데이터를 전송할 때 전송 지연시간을 보장하는 DCTW(Dual Channel Transmission Scheme for WBAN)기법을 제안한다. 무선 인체 통신 네트워크에서는 의학적인 응용을 고려하고 개발되었기 때문에, 의학적 데이터의 중요도에 따른 차등 전송 기법이 필요하다. DCTW에서는 응급 데이터 프레임의 전송을 위하여 협대역 채널을 사용하며 일반 데이터 프레임 전송을 위하여 광대역 채널을 사용한다. 협대역 채널을 통하여 응급데이터를 전송하기 때문에 긴급한 데이터를 보내고자 하는 노드가 데이터를 신속히 전송할 수 있도록 하여 전송 지연시간을 효과적으로 감소시켰다. 본 논문은 다양한 성능 분석을 통해 DCTW 기법이 다른 기법에 비해 우수함을 증명하였다.

• 무역상무연구
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• 제59권
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• pp.137-157
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• 2013

The Electronic Trade Finance not only has with the trait which is simple procedures, low cost but also easier access to using statistics compare to formerly paper based system. In Korea, all of trade finance system will be changed to electronic base by February 2014. The purpose of this research finds the using status and problems of the electronic local L/C and electronic purchase certificate, and suggests several improvements. First, the whole trade finance system should improve in terms of simple procedures, especially small and medium companies can use the system sufficient maximum limit. Second, the organizers, KTNET, KITA etc, need to the new electronic trade finance system promote to customers and training program for early settlement. It also has to manage at an unified system between IT and tex authorities. Third, small and medium size companies still think the charge for using high, so it need to make a resonable charge for using the electronic system to persuasive extent reasonable about it.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권7호
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• pp.3446-3464
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• 2017

Backoff mechanism serves as one of the key technologies in the MAC-layer of wireless mobile networks. The traditional Binary Exponential Backoff (BEB) mechanism in IEEE 802.11 Distributed Coordination Function (DCF) and other existing backoff mechanisms poses several performance issues. For instance, the Contention Window (CW) oscillations occur frequently; a low delay QoS guarantee cannot be provided for real-time transmission, and services with different priorities are not differentiated. For these problems, we present a novel Multi-Priority service differentiated and Adaptive Backoff (MPAB) algorithm over IEEE 802.11 DCF for wireless mobile networks in this paper. In this algorithm, the backoff stage is chosen adaptively according to the channel status and traffic priority, and the forwarding and receding transition probability between the adjacent backoff stages for different priority traffic can be controlled and adjusted for demands at any time. We further employ the 2-dimensional Markov chain model to analyze the algorithm, and derive the analytical expressions of the saturation throughput and average medium access delay. Both the accuracy of the expressions and the algorithm performance are verified through simulations. The results show that the performance of the MPAB algorithm can offer a higher throughput and lower delay than the BEB algorithm.

• 아동학회지
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• 제31권5호
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• pp.47-61
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• 2010

This study examined the moderated effects of self-control on the relationship between elementary school children's excessive use of the Internet and their stress levels. The participants were 403 elementary school children from Chungnam-do. The instruments used were the 'Internet Addiction Autodiagnosis Scale (K-Scale)', the 'Stress Scale' and the 'Self-control Rating Scale'. The collected data were analyzed by t test, F test and the Scheffe test for a post hoc test, Pearson's partial correlation and stepwise multiple regression, and Cronbach's ${\alpha}$ for reliability by SPSS program (17.0 version). The results were as follows : First, it was found that there were significant differences in terms of excessive use of the Internet, stress levels, and self-control by gender, grade, academic achievement, the beginning year of first Internet access and the number of hours of Internet usage hours per day. Second, there were significant positive correlations between excessive use of the Internet (r = .40, p < .001) and stress levels (r = .44, p < .001) and the immediate satisfaction of self-control. Finally, the immediate satisfaction of self control was seen to moderate the relationships between the total scores for the excessive use of the Internet and stress levels and between withdrawal of excessive use of the Internet and the accompanying stress levels.

• 한국안전학회지
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• 제32권2호
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• pp.124-131
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• 2017

This study aims to contribute to urban policy for more effective disaster prevention, as abnormal natural disasters are becoming more frequent. Up to now, the urban plan for disaster prevention in Korea merely includes basic principles and necessities of measures as an early stage. Furthermore, there are difficulties to make specific programs because the legal system, technical instruments, and financial supports are not sufficient. Therefore, this study figures out problems in the current plan related to urban prevention after analyzing the legal system and practices. Resulting from case studies in developed countries, the study draws significant implications, as follows: enhancing legally binding force; improving the procedures for the programs; establising technical infrastructure. It first suggests a way for the urban policy for disaster prevention by considering our local features comprehensively. It then defines the roles of central, local governemnts and research institutions, and the procedure for urban disaster prevention planning building on the individual roles. This study concludes that an emphasis should be placed on institutional tools necessary to publish technical guideline and establish the system so that urban planners more easily access to disaster risk information.

• 대한한의학원전학회지
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• 제24권3호
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• pp.49-64
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• 2011

Objectives : This paper is written to identify the origin of the nature of medicinals in Rhymes(藥性歌) in Korean medical books and to analyze their creativity. Methods : We analysed the nature of medicinals in Rhymes contained Chinese and Korean medical books. Results : The Korean medical book New Edition on Universal Relife(濟衆新編), published by Chosun government, recorded the nature of medicinals in Rhymes Recovery from All Ailments(萬病回春) mostly untouched. It can be evaluated the early model of Chosun's nature of medicinals in Rhymes. New Edition on Universal Relife, Gains and Losses of Medical Orthodoxy(醫宗損益) added new rhymes using familiar herbs and vegetables got easily, most new rhymes founded medicinal part of Treasured Mirror of Eastern Medicine (東醫寶鑑). Conclusions : The nature of medicinals in Rhymes is an approach to simplify and improve access on herbal medicine, and is quoted in various forms throughout medical books of Chosun. The entitling it as 'scientific research of herbal medicine based on the nature of medicinals in Rhymes' can clearly be seen as description about superficial result, to persist the decadence of Chosun medicine.

• KIEAE Journal
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• 제13권2호
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• pp.151-156
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• 2013

This study examines the properties of spaces where historical and cultural resources have been preserved in the street system of Daegu Yakryeong market district, by using Space Syntax methodology. The results were obtained through ASA(Angular Segment Analysis) on each node (spatial unit) in the street network. An overall characteristic of spatial configuration in street system of the surveyed district is that nodes in the street network tend to form socially integrated spatial structure to allow easy access to each space in the system. There are a small number of socially isolated spaces in the street system, which are located at nodes in narrow streets adjacent to the roadway outside the district, or in narrow alleys between early modern Korean buildings. More than half of the surveyed spaces have high levels of social integration, which contain buildings playing a central role of the community, a traditional street market, symbolic landmarks. In conclusion, it is expected that the achievements of this study will contribute in leading to rational land use planning for sound and sustainable development of historical and cultural resources in an urban district.

• 대한핵의학회지
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• 제24권2호
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• pp.307-316
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• 1990

Irradiation is widely used for the treatment of malignant diseases, and possibly cause the osteoporosis. The densitometry and bone scintigraphy are valuable when used to monitor the patients longitudinally to access the progression of osteoporosis and risk of osteoradionecrosis. To evaluate the osteoporosis after irradiation of Cobalt-60 gamma ray on the lumbar spines of New Zealand white rabbits, bone densitometry by dual photon absorptiometry and bone scintigraphy were performed weekly. The decrease of bone density began at the first week after irradiation, and were in the nadir at 4-6th week. The osteoblastic activity measured by bone scintigraphy decreased in the first week, and was in the nadir at 4-6th week. The severity of these changes were related to the radiation dose. In conclusion, the osteoporosis before the presentation of the osteoradionecrosis can be diagnosed early with the dual photon absorptionmetry and bone scintigraphy.

• 한국산업정보학회논문지
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• 제7권2호
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• pp.54-67
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• 2002

전자상거래는 고객에게 보다 시각적이고 청각적인 데이터에 쉽게 접근하게 만든다. 이러한 전자상거래의 기능은 기업들로 하여금 새로운 인터넷 기반의 판매활동을 가능하게 한다. 그러므로 전자상거래 시스템 구축은 기업들에게는 피할 수 없는 중요한 일이 되었다. 그러나 기업에 있어서 실제적인 전자상거래 시스템 구축은 초기의 엄청난 투자비용을 부담 해야하므로 매우 어려운 일이다. 위에서 언급한 것과 같이 전자상거래시스템 구축의 중요성을 고려하여 본 연구는 전자상거래 분야의 경영적 측면의 성공요인 분석을 통하여 한국 전자상거래 시장 분석을 하고자 한다. 본 연구의 결과가 미래의 한국 전자상거래 시장의 성장을 위한 확실하고, 실질적인 도움을 제공할 것이다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.1093-1094
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• 2006

City Train Technology that is large and complex system and consists of mechanical, electronic, electric, materials, computer, communication, civil/track etc. is very important area of railway industry, national fundamental industry. The standardization of city train system as a public transportation method and foundation of national economy is very important in order to do effective operation and to get fundamental technology, and the information system of the standards is required to operate the city train system effectively. By building data base of city train system design knowledge using computer-aided system engineering tool-Cradle, the system development issues and the design solutions are used by all engaged persons, and are managed by modeling and documentation. And this system will support architecture design consistently and effectively by applying this system to formalize early development process, to system requirements and configuration management, to system interface analysis and management and to system behavior analysis etc.. This study is for construction of data base of system design knowledge through making data base of many kinds of standards using CASE tool based on System Engineering Process, and introduces a model to support concurrent engineering for all engineers involved in system development allowing access to standard DB through Web from anywhere and at anytime.