• Journal of KIISE:Computer Systems and Theory
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• v.32 no.11_12
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• pp.654-662
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• 2005

Mobile portable devices for wireless network solely depend on a limited battery power. Therefore, we need to design for wireless communication protocols with an energy efficiency. TCP-Westwood is one of the most important approaches on TCP performance improvement in wireless environments that estimates the available bandwidth by using the sampling mechanism. The advantage is that data can be transmitted efficiently using the estimation of available bandwidth. However, when the sender with TCP-Westwood is in a wireless environment, it does not consider of the sampling mechanism operation. In this thesis, a new energy saving transport protocol, called E2TP(Energy Efficient Transport Protocol), is proposed to solve problems which occur when the sender with TCP-Westwood is in a wireless environment. Also, when there are packet loss while doing frequent link error in a wireless environment, E2TP provides the instantaneous segment size adjustment for a more efficient data retransmission. The simulation result proves that the proposed E2TP has better performance in energy efficiency and throughput than both TCP and TCP-Westwood.

• Journal of Internet Computing and Services
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• v.9 no.6
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• pp.179-188
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• 2008

Even though a lot of researches to improve the performance of TCP over wireless networks have been performed, the performance of TCP cannot satisfy users under high packet loss rate of wireless networks. This paper addresses the problem of TCP Westwood under high packet loss rate and reveals the reasons through the extensive simulation analysis. The ABE(Available Bandwidth Estimation) of TCP westwood becomes incorrect due to TCP dynamics of loss recovery. Based on this observation, we propose two algorithms for enhancing the correctness of ABE. We have evaluated the effects of the proposed algorithms through simulation. The proposed algorithms have achieved more correct ABE under the packet loss rate less than 1%.

• Journal of the Korean Society of Costume
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• v.59 no.2
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• pp.111-127
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• 2009

The purpose of this study is to understand the importance of exterior influential factors and kunstwollen(artistic will) of fashion designer. In order to investigate the differences which based on periodic backgrounds, social influences, cultural actualities and kunstwollen, Vivienne Westwood, Issey Miyake and Hussein Chalayan who have different social and cultural contexts are selected. Also through this research, people would understand the clothes has the values as the art works which have philosophy of creator and recognize the importance of fashion as an intermediation for comprehension of history, society and culture. Vivienne Westwood presents her honor to British history and culture in the way of her unique interpretation. Also she expresses the authority and the pride of woman who lives in the present age. Issey Miyake accomplishes the harmony of human body and soul. He attains the most perfect beauty through incomplete beauty of cloth. Hussein Chalayan produces his fashion works as a form of concept which is keep asking question about existence of human being. Fashion is the work of art which Is based on the relationship between clothes, human body and spirit. The fashion designer makes human life has value through his or her creations and tries to communicate with the world.

• Nuclear Engineering and Technology
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• v.37 no.5
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• pp.401-422
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• 2005

We review here research and development progress achieved in US Plasma Chamber technology roughly over the last decade. In particular, we focus on two major programs carried out in the US: the APEX project (1998-2003) and the US ITER TBM activities (2003-present). The APEX project grew out of the US fusion program emphasis in the late 1990s on more fundamental science and innovation. APEX was commissioned to investigate novel technology concepts for achieving high power density and high temperature reactor coolants. In particular, the idea of liquid walls and the related research is described here, with some detailed examples of liquid metal and molten salt magnetohydrodynamic and free surface effects on flow control and heat transfer. The ongoing US ITER Test Blanket Module (TBM) program is also described, where the current first wall/blanket concepts being considered are the dual coolant lead lithium concept and the solid breeder helium cooled concepts, both using ferritic steel structures. The research described for these concepts includes both thermofluid MHD issues for the liquid metal coolant in the DCLL, and thermomechanical issues for ceramic breeder packed pebble beds in the solid breeder concept. Finally, future directions for ongoing research in these areas are described.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.05a
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• pp.995-998
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• 2008

무선 통신 기술의 발전과 함께 802.11n과 같은 광대역 네트워크 인프라의 구축이 확대됨에 따라, 이에 적합한 높은 성능을 낼 수 있는 전송 계층의 프로토콜이 필요하다. 유선 환경에서 개발된 TCP(Transmission Control Protocol)는 현재 가장 널리 이용하는 전송 프로토콜이다. 하지만 높은 에러율과 긴 딜레이가 발생하는 무선 네트워크상에서는 패킷 손실의 원인을 구별하지 못하기 때문에 성능이 저하된다. 또한, 광대역폭을 지원하는 초고속 네트워크상에서 TCP가 동작할 경우 기존 무선 네트워크에서 처리하는 혼잡윈도우 값보다 커진 값을 제대로 처리하지 못하기 때문에 가용대역폭을 활용하지 못하는 문제점이 발생한다. 따라서, 본 논문에서는 초고속 네트워크 안에서 slowstart threshold에 기반하여 가용대역폭을 동적으로 획득하고, 높은 전송률을 보장하는 TCP VEST(TCP Vegas-based Estimator with Slowstart Threshold)를 제안한다. TCP VEST는 기본적으로 송신자기반 무선네트워크에서 우수한 성능을 지원하는 TCP WestwoodVT의 패킷 손실원인 구분법을 사용한다. 그리고 TCP VEST는 패킷 손실의 원인을 구분하고 각각의 경우에 따라서 전송량을 slowstart threshold 값의 변화에 맞춰 조절한다. NS-2를 통한 성능평가에서 VEST는 WestwoodVT와 비교했을 때 링크 에러율이 1%인 환경에서는 20% 이상의 전송률 향상을 나타내며, Westwood와 비교했을 때는 60%의 성능향상이 있다. 또한 초고속 네트워크에서 5%와 10% 사이의 에러율을 가질 때에는 WestwoodVT와는 50%, Westwood와는 300% 이상의 성능향상이 나타남을 보인다. 이를 통해 VEST가 기존의 무선 네트워크와 더불어 초고속 네트워크에서도 동적으로 대역폭을 획득함으로써 높은 전송률을 지원하는 것을 입증한다.

• Proceedings of the Korean Information Science Society Conference
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• 2008.06d
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• pp.137-140
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• 2008

TCP는 유선망에 최적화되도록 변화 된 결과, 무선망에서는 무선망의 단점인 비연속적인 연결 링크로 인해 전송손실이 발생하게 된다. 그러나 어플리케이션 프로그램에서는 이러한 문제로 인해 발생되는 오류를 네트워크의 혼잡으로 인한 손실로 오인하게 된다. 그 결과 어플리케이션 프로그램에서는 혼잡제어 메커니즘이 수행되어 전송율을 줄이므로 네트워크 성능이 저하되는 문제점을 초래한다. 이러한 이유로 최근 유무선 혼합망에서 TCP의 성능을 향상시키기 위한 연구가 활발히 이루어지고 있다. 본 논문에서는 기존에 제안된 개선 모델들 중 상대적으로 많이 사용되고 있는 TCP Westwood에 대해서 성능을 보완하는 기법을 제안하고자 한다.

• Journal of the Korean Society of Costume
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• v.47
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• pp.5-18
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• 1999

This study focus on the history of Scottish kilt and the application of kilt designed by Vivienne Westwood 1993 F/W. Up to late the 16 Century saffron shirt was worn among Highland men and belted plaid become common dress after the 17 Century. The early the 18 Century belted plaid have developed as a kilt separated to a upper and a lower skirt style. However Government banned wearing tartan and kilt after Culloden battle (1745) as highland Dress(tartan, kilt, belted plaid etc) was the symbol of rebellion. This legislation by Hanoverian authority continued for 35 years. Although most of tartan was disappeared during those period it has become popular among European upper class after george IV's visiting Scotlan in 1822. Highland Dress become Scottish national dress after Industrial revolution. Currently Vivienne Westwood's 93 F/W using tartan and kilt and its accessaries those items were successfully transformed modern ladies dress.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11b
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• pp.939-942
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• 2003

TCP Westwood[1]는 송신측에 수신된 ACK를 통해서 대역폭을 계산하여 데이터를 전송하는 기법이다. 위성망 같이 손실률이 매우 높은 환경을 위해 TCP Westwood에서는 기존의 Bu]k Retransmission[2] 기법을 보안 하였다. 하지만 Bulk 재 전송 기법은 불필요한 데이터도 함께 재전송하기 때문에 성능이 저하되게 된다. 이 논문에서는 재 전송 패킷의 수를 적절히 조절하는 Adaptive Bulk Retransmission 기법을 제안하고자 한다.

• Journal of the Korea Fashion and Costume Design Association
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• v.7 no.2
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• pp.101-110
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• 2005

Vivienne Westwood could be placed in a unique position in the contemporary fashion design. She has never belonged in a core group of mainstream fashion designer but not been always in an outsider position. She got from mainstream fashion designer circles enormous appreciation, even established fashion industry was influenced by her fashion design. She began her fashion design with rebellious T-shirts like 'destroy' T-shirt, chicken-bone T-shirt, and nipple-zipper T-shirt, all of which revealed her disgust against establishment. All these T-shirts testify her total negation tendency in her youth. However, she did not continue to keep such a kind of total negation attitude against establishment In 1980s she changed her political attitude towards establishment, and this change also found a reflection in her fashion design. In her pirate-collection the dark image of her fashion in the 1970s changed into a totally different bright image with full of gold colour. Although this collection had radiated brightness, it contained still outsider character from mainstream fashion design. The following fashion design in 1980s and 1990s evolved further on the line of Pirate-collection, but they continued to contain certain outsider characteristics. Vivienne Westwood kept some kind of anti-establishment attitude, and this attitude more or little came to the surface of her design. She was always political and critical to the establishment. In 2005, in her 64, she designed a liberty T-shirt, which showed her political attitude and her engagement in social issues. Also it showed the change from the early total negation to the constructive critical affirmation. In this paper the relation between the fashion design of Vivienne Westwood and her political attitude and the influence of her political attitude to her fashion design is analyzed.

• Korean journal of applied entomology
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• v.57 no.3
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• pp.137-141
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• 2018

Neanastatinae Kalina, 1984 is reported for the first time from South Korea with two newly recognized species of Metapelma Westwood, 1835: M. beijingensis Yang and M. pacificum Nikol'skaya. Also, male of M. pacificum is discovered and diagnosed for the first time. Key to South Korean species of Metapelma, diagnoses and photographs of the diagnostic characters are provided along with a key to species of the genus.