• Journal of information and communication convergence engineering
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• 제10권3호
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• pp.237-241
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• 2012

In wireless sensor networks, the importance of transporting data correctly with reliability is increasing gradually along with the need to support communications between the nodes and sink. Data flow from the sink to the nodes requires reliability for control or management that is very sensitive and intolerant of error; however, data flow from the nodes to the sink is relatively tolerant. In this paper, with emphasis on the data flow from the sink to the nodes, we propose a mechanism that considers accurate transport with reliability hop-by-hop. During the process of sending the data, if errors occur or data is missing, the proposed mechanism supports error recovery using a fixed window with selective acknowledgment. In addition, this mechanism supports congestion control depending on the buffer condition. Through the simulation, we show that this mechanism is accurate, reliable, and proper for transport in wireless sensor networks.

• International Journal of Advanced Culture Technology
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• 제9권3호
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• pp.221-231
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• 2021

The purpose of this study is to examine the characters and sustainability of built heritage featured in the eight-scenery listings of Gyeonggi municipalities in South Korea. Eight scenery is a place marketing medium that reflects the community's appreciation of the selected resources. For a research method, we utilize framework analysis to understand the cultural resources in three categories: heritage value identification, preservation, and dissemination. Primary sources for data collection include the chosen eleven cities' eight-scenery webpages, the National Cultural Heritage Portal, and articles about the built heritage resources included in the eight scenery. The results of this study show the public's acknowledgment of diverse built heritage, from prestigious monuments to local heritage interpretations, and various preservation and public program development approaches. The conclusion discusses the research findings regarding historic preservation, sustainable development, and place marketing.

• Journal of Nutrition and Health
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• 제52권2호
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• pp.242-242
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• 2019

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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• pp.477-480
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• 2008

In this paper, we design the TCP-Light protocol for directly connecting a sensor network with Internet. When we are monitoring the data and controlling of the sensor node, the sensor network must be connected to Internet. But TCP in wireless networks has a number of performance problems which is high bit-error rates and a hardware constraint. Moreover, the end-to-end acknowledgment and retransmission scheme employed by TCP causes expensive retransmissions along every hop of the path between the sender and the receiver. This paper introduces The TCP-Light protocol which increases TCP performance in wireless sensor networks, decreases the number of end-to-end retransmissions and decreases memory consumption.

• Proceedings of the Korean Information Science Society Conference
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• 한국정보과학회 2006년도 한국컴퓨터종합학술대회 논문집 Vol.33 No.1 (D)
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• pp.319-321
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• 2006

본 논문에서는 블록 FEC(Forward Error Correction) 알고리즘을 적용한 IEEE 802.11e MAC(Medium Access Control)의 블록전송모드(Block Transfer Mode)의 성능을 분석한다. 성능 향상을 위해서 IEEE 802.11e MAC은 TXOP(Transmission Opportunity)시간 동안 특정 스테이션(station)에게 독점적인 전송 기회를 부여하며, 이 기간동안 하나의 블록 즉 연속적으로 여러 개의 데이터 프레임(frame)을 전송한다. 수신자는 블록내의 각 프레임에 수신 여부를 블록 ack (block Acknowledgment)방식, 즉 하나의 ack 패킷이 모든 수신 프레임의 일련번호를 모아 알려 준다. 그러나 오류가 빈번한 무선 채널 환경에서는 블록 ack 방식을 사용하더라도 빈번한 재전송으로 인해 채널의 성능이 현저히 감소한다. 이러한 문제를 해결하기 위해 심볼 단위로 오류를 복원하는 블록 FEC 알고리즘을 적용할 수 있는데, 본 논문에서는 802.11e에서 FEC 알고리즘을 적응하는 두 가지 방식의 성능을 해석적으로 분석한다. 즉 두 가지 방식은 프레임 당 블록 FEC를 적용하는 방법과 전체 블록 내의 프레임을 하나의 데이터로 간주하여 FEC를 적용하는 방식이다. 본 논문에서는 이 들 두 가지 방식의 채널 성능 향상 정도와 블록 ack만을 사용한 경우의 성능을 수식적으로 계산한다. 실험에 의하면 BER이 $10^{-4}$인 채널 환경에서 블록 FEC를 적용한 방식이 블록 ack를 사용한 방식에 비해 약 1.5%의 성능향상을 보인다.

• Safety and Health at Work
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• 제3권1호
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• pp.11-16
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• 2012

Lead poisoning is one of the earliest identified and most known occupational disease. Its acute effects have been recognized from antiquity when this condition principally afflicted manual workers and slaves, actually scarcely considered by the medicine of that time. The Industrial Revolution caused an epidemic of metal intoxication, urging scientists and physician of that period to study and identify specific symptoms and organ alterations related to chronic lead poisoning. During the 20th century, the acknowledgment of occupational and environmental toxicity of lead fostered public awareness and legislation to protect health. More recently, the identification of sub-clinical effects have greatly modified the concept of lead poisoning and the approaches of medicine towards this condition. Nowadays, lead poisoning is rarely seen in developed countries, but it still represents a major environmental problem in certain areas. Consequently, it may appear as a paradigm of "occupational and environmental disease," and the history of this condition seems to parallel the historical development of modern "Occupational and Environmental Health" as a more complete medical discipline.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권7호
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• pp.1831-1853
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• 2012

By sending periodically short bursts of traffic to reduce legit transmission control protocol (TCP) traffic, the low-rate denial of service (LDoS) attacks are hard to be detected and may endanger covertly a network for a long period. Traditionally, LDoS detecting methods mainly concentrate on the attack stream with feature matching, and only a limited number of attack patterns can be detected off-line with high cost. Recent researches divert focus from the attack stream to the traffic anomalies induced by LDoS attacks, which can detect more kinds of attacks with higher efficiency. However, the limited number of abnormal characteristics and the inadequacy of judgment rules may cause wrong decision in some particular situations. In this paper, we address the problem of detecting LDoS attacks and present a scheme based on the fluctuant features of legit TCP and acknowledgment (ACK) traffic. In the scheme, we define judgment criteria which used to identify LDoS attacks in real time at an optimal detection cost. We evaluate the performance of our strategy in real-world network topologies. Simulations results clearly demonstrate the superiority of the method proposed in detecting LDoS attacks.

• The Journal of the Korea Contents Association
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• 제9권10호
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• pp.492-499
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• 2009

This research was conducted in order to know how influential the acknowledgment of factors such as the quality of educational contents and the conducting of off-line lectures is in terms of effective learning for leaners. Based on the satisfaction-importance model of the multi-attribute attitude model, this study would like to clarify the degree to which the quality of on-line contents of on-line education and the simultaneous conducting of off-line lectures influences one's learning attitude. On-line contents satisfaction will evaluated through the three categories: audio lectures, video lecture and WEI lectures, which make up the quality of on-line contents. We would also like to do a survey on the transformation of learning attitudes when on-line and off-line lectures were conducted simultaneously.

• Proceedings of the Korea Contents Association Conference
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• 한국콘텐츠학회 2009년도 춘계 종합학술대회 논문집
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• pp.373-377
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• 2009

This research was conducted in order to know how influential the acknowledgment of factors such as the quality of educational contents and the conducting of off-line lectures is in terms of effective learning for leaners. Based on the satisfaction-importance model of the multi-attribute attitude model, this study would like to clarify the degree to which the quality of on-line contents of on-line education and the simultaneous conducting of off-line lectures influences one's learning attitude. On-line contents satisfaction will evaluated through the three categories: audio lectures, video lecture and WBI lectures, which make up the quality of on-line contents. We would also like to do a survey on the transformation of learning attitudes when on-line and off-line lectures were conducted simultaneously.

• Journal of the Korea Fashion and Costume Design Association
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• 제13권3호
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• pp.45-54
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• 2011

The purpose of this study is to help understanding of east-west culture fusion in fashion since 2000 years, to play a guideline's role in the development on fashion designs study. The methods of this study are academic literatures as well as practical study through case studies about actual works. Tendency of east-west culture fusion in fashion since 2000 years is shape and performance, pattern, accessary. Shape and performance are reinterpreted through east folk fashion transforming on west fashion, pattern shows traditional pattern of each nations, but letters of typical of each nations appears for new pattern which expresses nation identification. Accessary is in the harmony with east -west fashion culture like that without transform. Aesthetic value of east-west culture fusion in fashion since 2000 years is summerised opening, co-ownership, and amusement. First, opening is positiveness of acception and acknowledgment for other. Second, co-ownership turns towards humanism, and proves participating in globalism and really global village. Third, amusement is to express freedom, and to reveal privately emotion concealing in public area.