• 한국정보통신설비학회:학술대회논문집
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• 2009.08a
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• pp.355-358
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• 2009

센서 네트워크에 대한 연구가 활발히 이루어지면서 센서 네트워크 보안에 대한 문제점이 많이 야기되고 있다. 무선 센서 네트워크에서는 개방된 환경에서 제한적인 자원을 가지는 노드들로 구성되어 있다. 개방된 환경에 배치된 노드들은 공격자에게 쉽게 노출되어질 수 있다. 공격자는 노드를 물리적으로 포획하여 데이터 인증에 사용하는 인증키와 같은 보안 정보들을 획득할 수 있다. 공격자는 포획된 노드를 통하여 허위 보고서로 무선 센서 네트워크에 쉽게 삽입시킬 수 있다. 이는 허위 보고서로 인한 혼란 및 위조 정보의 전달과정에서 발생하는 에너지 고갈 등의 문제점을 유발시키게 된다. 이러한 허위 보고서를 조기에 탐지 및 폐기하기 위하여 동적 여과 프로토콜(DEF: Dynamic En-route Filtering scheme)이 제안되었다. DEF에서 인증키를 재배포 하는 주기는 보안 강도와 비용을 트레이드-오프 하는 관계에 놓여있으므로 매우 중요하다. 본 논문에서는 센서네트워크에서 동적 여과 프로토콜의 인증키 재배포 주기를 결정하는 기법을 제안한다. 배포된 노드들의 위상변화, BS까지 도달한 허위보고서 비율, 공격자에게 포획된 노드의 수 등을 고려하여 재배포 여부를 결정하고 재배포가 결정되면 각 클러스터 헤드들에게 재배포를 명령하게 된다.

• Journal of Life Science
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• v.12 no.5
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• pp.549-554
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• 2002

Taraxacunf mongofieum Hand-Mass aqua-acupuncture solution (TMAS) was prepared and investigated og, the effect on initiation of carcinogenesis. The following effe.Is as a blocking agent were measured. .(a) Indu.ction of quinone reductase, (b) Induction of glutathione S-transferase activity (c) Increase of reduced glutathione. TMAS was potent inducer of quinone reductase in Hepa Iclc7 murine hepatoma cells. Clutathione S-transferase activity was increased with TMAS. In addition glutathione levels were increased about 1.6-fold with TMAS in cultured murine hepatoma Hepa Iclc7 cells.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.3
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• pp.98-106
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• 2007

포공영(蒲公英)은 예로부터 청열해독약(淸熱解毒藥)으로 사용되어 왔으며 NO가 염증의 한 요인이기 때문에 포공영의 항염증 작용기작을 밝히기 위하여 LPS로 자극된 대식세포주 RAW264.7 세포에서 포공영 열수 추출물 (AETM)의 NO 생성에 미치는 효과를 조사하였다. 포공영은 NO 생성 및 iNOS 단백질 발현, iNOS mRNA 발현을 저해하였으며, 전사인자인 $NF-kB$의 핵으로의 이동을 억제하였다. 또한 LPS에 의해서 활성화되는 ERK/MAPK 효소의 활성을 현저히 억제하였다. 이 결과들로 보아 포공영의 항염증 작용이 ERK/MAPK 활성 저해 및 $NF-kB$ 활성 저해로 인한 iNOS 발현의 억제 때문인 것으로 사료된다.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.5
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• pp.413-418
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• 2002

This paper proposed a feed-forward adaptive position controller that is robust for variable Inertia. The control system consists of PI Position controller, feed-forward and model reference adaptive control. A parameter g(t) of the feed-forward adaptive position controller is adapted by using both the reference model speed and position error. So it improves the transient response and reduces the settling time. And normalization function Is used to make linear adaptation time. The validity of the feed-forward adaptive controller is confirmed by simulation results.

• Archives of design research
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• v.14 no.1
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• pp.167-176
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• 2001

In 21st century as a digital era, visual communication design becomes more important than any other period. Recently, traditional typographic design for the communication with emphasis on the readability and experimental typographic design with emphasis on the expressionism contrary to the traditional concept coexists. There have been experiments on the typography with the establishment of modem art concept in the past: this trend is more obvious since the 1980s with the technological development of desktop computer. In this study, experimental typography works by David Carson who is one of the most representative graphic designers of the 1990s are analyzed in detail, and problems and prospects of this experimental typography in a digital era contrary to the traditional viewpoint we discussed.

• Journal of Biomedical Engineering Research
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• v.19 no.3
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• pp.215-224
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• 1998

This paper is fundamental study to develope the extracorporeal liver support system for patient with fulminant hepatic failure(FHF) or being expected for orthotopic liver transplantation. The polyurethane foam, which is composed of the density of 33kg/m3, the average pore diameter of 500${\mu}{\textrm}{m}$, the closed window of 60-70%, was manufactured with the prepolymer of 15% NCO-, Hepatocytes were inoculated to form spheroids in polyurethane foam. The time of spheroid formation in BSA(Bovine Serum Albumin) coated polyurethane foam was shorter than that in raw polyurethane foam. To verify the function of hepatocyte spheroids, we measured ammonia removal rate, urea and albumin secretion rate. Polyurethane foam was suitable for culture of hepatocyte spheroids. And culture of hepatocyte spheroids in polyurethane foam has high possibility in using as an extracorporeal liver support system.

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.9
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• pp.475-482
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• 2005

String data containing wildcard characters may represent certain patterns in texts. A subsumption relation between two patterns can be defined by a subset relation between sets of strings that match those patterns. Thus, the subsumption relation check is important to determine whether each pattern represents a set of strings without any overlap with another pattern. In this paper, we propose an effective algorithm that can determine subsumption relation between strings with wildcard characters. First, we consider a simple extension of the suffix tree algorithm so that it nay include wildcard characters and then we propose another method that checks the subsumption relation by dividing a suffix tree structure at each location of string data.

• The Journal of the Korea Contents Association
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• v.22 no.8
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• pp.227-234
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• 2022

This study identified the characteristics of surrealistic art and examined the choreography method based on the representative work of choreographer William Forsythe. Forsyth developed into a ground breaking performing art through surrealistic characteristics and his own method, and sought to find a new body image based on this original choreographic approach. Through this, it was found that the destruction and dismantling of forms, which are surrealistic art characteristics, appeared as separate movements, space reconstruction, and special objects in the choreography method of Forsythe. Therefore, the purpose of this paper is to investigate the characteristics and forms of surrealism and to identify the surrealistic elements that appear in William Forsythe's.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.3
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• pp.111-117
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• 2009

Food and Agricultural Organization (FAO) Penman-Monteith (PM) equation is one of the most widely used equations for predicting evapotranspiration (ET) of crops. The ET rate and the base crop coefficients ($K_{cb}$) of the two different grape vines (i.e., Campbell Early and Kyoho) cultivated in Suwon were calculated by using the FAO PM equation. The ET rate of Campbell Early was $2.41\;mm\;day^{-1}$ and that of Kyoho was $2.22\;mm\;day^{-1}$ in August when the leaf area index was 2.2. During this period, the $K_{cb}$ of Campbell Early based on the FAO PM equation was on average 0.49 with the maximum value of 0.72. On the other hand, the $K_{cb}$ of Kyoho was averaged to be 0.45 with the maximum value of 0.64. The seasonal leaf area index for two grape cultivars was measured as 0.15 in April, 0.5 in May, 1.4 in June, 2.2 in July-September, and 1.5 in October. The $K_{cb}$ of Campbell Early showed a seasonal variation, changing from 0.03 in April to 0.11 in May, 0.31 in June, 0.49 in July-September, and 0.33 in October. The magnitudes and the seasonality of $K_{cb}$ of Kyoho were similar to those of Campbell Early.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.4
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• pp.413-420
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• 2012

An aluminum foil-laminated sheet is a laminated steel sheet on which aluminum foil is adhesively bonded. It is usually used on the outer panel of home appliances to provide an aluminum feeling and appearance on the surface of the product. The delamination of aluminum foil is one of the main problems during the stretch forming process. The purpose of this study is was to determine the delamination limit of an aluminum foil-laminated sheet in the stretch forming process. The delamination was dependent on the bonding strength between aluminum foil and steel sheet. The fracture behavior of the interface between the aluminum foil and the steel sheet was described by a cohesive zone model. A finite element was conducted with the cohesive zone model to analyze the relationship between the delamination limit and the bonding strength of the interface. The interface bonding strength was evaluated by lap shear and T-peel test. The delamination limit of the aluminum foil-laminated sheet was determined by using the bonding strength of the steel sheet. The delamination limit was also verified by the Erichsen test.