• 대한전자공학회논문지TC
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• 제44권10호
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• pp.20-28
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• 2007

IEEE 802.15.4를 기반으로 하는 Zigbee 센서 네트워크에서는 전송되는 패킷에는 2byte의 지역 주소가 존재한다. Ziebee 센서 네트워크 내에서 이 2byte의 주소를 가지고 각 센서의 주소를 식별한다. 이러한 Zigbee 센서 네트워크는 많은 센서들을 하나의 네트워크로 구성할 수 있어야 ubiquitous 시대를 뒷받침 할 수 있는 솔루션으로 자리매김할 수 있다. 그러나 Zigbee 계층 구조에서 표준에 제정되어 있는 알고리즘인 Cskip 알고리즘을 이용한 할당 방식에는 많은 수의 센서를 배치하는 것에 문제가 있다. Cskip 알고리즘을 이용하여 주소를 할당하기 위해서는 라우터나 코디네이터가 가질 수 있는 자식노드의 최대 개수, 자식노드가 라우터로 될 수 있는 최대 개수, 네트워크의 최대 깊이를 알아야 한다. 이러한 네트워크는 유연성이 없고 공간적이 측면으로 봤을 때 주소 할당에 있어서도 많은 낭비를 초래하게 된다. 본 논문에서는 이러한 주소 공간의 낭비를 최소화 할 수 있는 주소할당 알고리즘을 제안한다.

• 한국잡초학회지
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• 제10권3호
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• pp.233-239
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• 1990

Alachlor를 귀리(Avena sativa L.)의 뿌리에 처리시(處理時) peroxidase의 변화(變化)에 대해서 조사(調査)한 결과(結果)는 다음과 같다. 1. Alachlor 처리구(處理區)는 무처리구(無處理區)에 비해서 $10^{-6}M$에서 0.20 unit, $10^{-3}M$은 0.27 unit로, 농도(濃度)가 높을수록 peroxidase의 합성량(合成量)이 증가(增加)되었다. 2. Peroxide를 직접 귀리의 뿌리에 12시간(時間) 처리시(處理時), 65mM에서 16%, 130mM에서 59%의 뿌리 생장(生長) 억제(抑制)되었다. 3. 귀리의 근단(根端) 분열(分裂) 조직(組織)은 4개의 동위(同位) peroxidase로 분리(分離)되는데, alachlor 처리시에는 특히 $P_1$, $P_6$와 $P_7$의 isoperoxidaserk 생성(生成)되었으며, SDS-PAGE에서 귀리의 근단(根端) 조직(組織)은 100kD 이하의 단백질(蛋白質)로 구성(構成)되어 있다.

• 한국화재소방학회논문지
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• 제12권2호
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• pp.43-59
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• 1998

화재위험성이 큰 유흥업소에서 주로 사용하는 내장재중 방염 카퍼l트, 방영 후처리 합환, 쇼파 례자동 3가지 시료에 대한 연소특성과 CO, CO2, 02, NO., S02, HCN, HCl둥 독성가스를 검출하여 화재 위험 성을 비교명가 하였다. 연소특성에 있어 방염 카페트가 방염 후처리 합판, 쇼파 레자 보다 연소가 잘 되 었고, 폭연 연소가 일어났다. 모든 시료에서 CO의 발생은 연소시작 후 1분 이내에 치사농도를 상회(上 ) 하였으나 NOx와 S02는 치사농도를 상회(上 ) 하지 않았지만. HCN는 카페트에서 쇼파 레자 보 다 20.6배, 방염 후처리 합판 보다 4.6배가 검출 되었고. HCl은 차페트에서 쇼파 례자 보다 4.48배, 방 염 후처리 합판 보다 2.47배가 검출 되었다. 이상과 같이 3종의 내장재중 방염 차페트가 화재위험성이 가장 높다는 결론을 얻을 수 있었다.

• 수산해양기술연구
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• 제53권4호
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• pp.413-422
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• 2017

The objective of this study was to prove possible effects of a habitable place for fish around semi-submersible drilling rig which measured underwater radiated noise, irradiance distribution of rig's light and conducted experimental fishing in Malaysia territory and observed for distribution of fishes around the rig by ROV during drilling operation in the East Sea of Korea. As a result underwater radiated noise was $130dB/{\mu}Pa$ from 156.25 to 187.50 Hz, irradiance distribution of light was between 21.5 and 43.1 lx. Despite this result, underwater radiated noise was not a threat to fish around rig and low irradiance distribution of light also played a role in the luring influence of the fishes at night. Fish showed up in the beginning of drilling operation and at the end of drilling operation. However, there are few fish in the midst of drilling operation. The main reason for this result was the destruction of the habitable place due to blow out mud and broken pieces of ground formation in drilling hole. The results are expected to contribute to reasonable fishery management around rig.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1995년도 춘계학술발표회 초록집
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• pp.185-198
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• 1995

This is an experimental study conducted to visualize the nucleate boiling phenomena and flow regimes occurring inside the liquid pool in a closed two-phase thermosyphon. To meet this purpose, an annular-type thermosyphon was designed and manufactured using a glass tube and a stainless steel tube, being assembled axisymmetrically. The heat to be supplied to the working fluid is generated within a very thin layer of stainless steel tube wall by applying a high frequency electromagnetic field through the induction coil, axisymmetrically set around the evaporator zone. Some important results were as follows ; 1) Considering the structural complexity of the tested thermosyphon, it showed good performance for the range of heat flux 2＜ q" ＜25kW/$m^2$ and saturation vapor pressure, 0.1＜Pv＜1.1bar 2) different type of nucleating boiling regimes were observed as described below, -Pulse boiling regime : Flow pattern changed cyclically with time during 1 cycle of pulse boiling process. The onset of Nucleation was followed by expulsive growing of vapor bubble, resulting in the so called blow-up phenomenon, massive expulsion of large amount of liquid around the bubble. -Transient : Some spherical vapor bobbles were observed growing out from 2~3 nucleating sites, that was dispersed at the lower part of the heated tube wall in the liquid pool. But the rest upper region above the nucleating sites were filled with churns or bubbles of vapor. -Continuous nucleate boiling regime : The whole zone of evaporator was filled with lots of spherical vapor bubbles, and the bubbles showed tendency to decrease in diameter as the heat flux increased.ased.

• 한국수소및신에너지학회논문집
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• 제23권4호
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• pp.412-419
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• 2012

Increasing demand for natural gas and higher natural gas prices in the recent decades have led many people to pursue unconventional methods of natural gas production. POSCO-Gwangyang synthetic natural gas (SNG) project was launched in 2010. As the market price of natural gas goes up, the increase of its price gets more sensitive due to the high cost of transportation and liquefaction. This project can make the SNG economically viable. In parallel with this project, KEPCO (Korea Electric Power Corporation) joined in launching the SNG Quality Standard Bureau along with KOGAS (Korea Gas Corporation), POSCO and so on. KEPCO Research Institute is in charge of SNG fueled gas turbine combustion test. In this research, several combustion tests were conducted to find out the effect of hydrogen contents in SNG on gas turbine combustion. The hydrogen in synthetic natural gas did not affect on gas turbine combustion characteristics which are turbine inlet temperature including pattern factor and emission performance. However, flame stable region in ${\Phi}$-Air flow rate map was shifted to the lean condition due to autocatalytic effect of hydrogen.

• 한국한의학연구원논문집
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• 제15권2호
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• pp.1-19
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• 2009

Some researchers who once studied Uirimchualyo have paid good attention to the connection between Donguibogam & Uirimchualyo because of their similarity. So, after reviewing the Sequel of Uirimchualyo, in terms of its editing purpose and the list of contents, especially focused on throat sickness, here I report on the conclusions I come to. Firstly, the Sequel of Uirimchualyo was a monumental edition in concert with the enthronement of Kwanghaegun, and printed at demand of new medical knowledge, which was required to add to the existing Uirimchualyo, written by best-noted doctor, Yang Yesoo, and in need of simpler medical textbook to help people's recovery from the damage of Japanese invasion in the year of Imjin & Jeongyoo. Secondly, all the contents read in the Sequel of Uirimchualyo, were quoted from Kogumuigam, compiled by Kong Shin, Manbyonghoichun, edited by Kong Jeonghyun, Dangaeshim bupbuyo, published by Bang Kwang, and Uihakipmun, edited by Lee Cheon. Thirdly, The reason of similarity between Uirimchualyo and Donguibogam is that the Sequel of Uirimchualyo was made by adding new medical knowledge to the existing Uirimchualyo, and that many of contents of the Sequel of Uirimchualyo were quoted in Donguibogam. Fourthly, regarding throat sickness, medical knowledge on acute fever was supplemented in the Sequel of Uirimchualyo, and the emergency medical treatment methodology like "blow-in-throat" was newly introduced. This treatment is worth being employed to treat acute suffocation with swollen throat in modern acute-infection sicknesses. Fifthly, the Sequel of Uirimchualyo made up for brief description of the existing Uirimchualyo, offered more convenience of users compared with too overscaled Hyangyakjipseongbang & Uibangryuchui, and was more complete than Kookupbang which was loose, incomplete, and sometimes risky. And it took firm hold before Donguibogam, and eventually made a great contribution toward Donguibogam.

• 한국의류산업학회지
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• 제17권2호
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• pp.147-156
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• 2015

Lately, unique hats, which worn by iconic figures in fashion industry, like Anna Piaggi and Isabella Blow to express the originality and self-awareness, received attention from the mass media along with their styles. The purpose of this research is to investigate, analyze, and media-specific characteristics of objet hats which are used to show various items, shape up targets, and express the concept of attires. In order to fulfill this, this study focuses on objet hat designers who have been influential from the 1980's to recent years. As for the research methodologies, this study conducts investigating examples from fashion related books, research papers, and websites along with literary research. Study of objet hat is based on cases and works of designer in objet hat in contemporary fashion expression shape. As a result, objet hat, First, the experimental work to maximize the effectiveness as a fashion objet containing the concept of designer in the runway shows. Second, as pieces displayed on art galleries and museums, objet hats are recognized as artistically defined world of conceptual designers' imaginations. Third, objet hats function as ways of celebrities' expression, who affects the public as fashion leaders. Lastly, objet hat designers's activities operate the story and notion contained in the work through a variety of genres. Objet hats, an independent fashion genre, which symbolize creativity and freedom, influenced the fashion industry with astonishing materials, forms, and decorations.

• 한국전자파학회논문지
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• 제18권6호
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• pp.656-663
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• 2007

본 논문은 접지된 2중의 유전체 평면 사이에 변화하는 저항율을 갖는 저항 띠 격자 구조로 임의의 각도로 입사되는 E-분극 전자파 산란 문제를 모멘트 법으로 해석하였다. E-분극 산란에서는 저항 띠의 모서리 양끝에서 유도되는 전류 밀도가 매우 높을 것으로 예측되므로, 이 특성과 일치하는 기저 함수를 직교 다항식 일종인 2종 Chebyshev 다항식의 급수로 전개하여 수치 해석하였다. 산란 전자계는 주기적인 구조에 대응시킬 수 있는 Floquet 모드 함수의 급수로 전개하였고, 미지의 계수를 구하기 위하여 경계 조건을 적용하였다 또한, Fourier-Galerkin 모멘트 법을 적용함으로써 접지된 2중의 유전체 사이에 다양한 저항율을 갖는 저항 띠에 대해 기하광학적인 정규화 된 반사 전력에 관한 스트립 폭과 주기, 입사각의 영향 등을 수치 해석하였다.

• 대한두개안면성형외과학회지
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• 제18권4호
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• pp.249-254
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• 2017

Background: Lower eyelid incisions are widely used for the orbital approach in periorbital trauma and aesthetic surgery. In general, the subciliary approach is known to cause disposition of the lower eyelid by scarring the anterior lamella in some cases. On the other hand, many surgeons believe that a transconjunctival approach usually does not result in such complications and is a reliable method. We measured positional changes in the lower eyelid in blowout fracture repair since entropion is one of the most serious complications of the transconjunctival orbital approach. Methods: To measure the positional changes in the lower eyelids, we analyzed preoperative and postoperative photographs over various time intervals. In the analysis of the photographs, marginal reflex distance 2 ($MRD_2$) and eyelash angle were used as an index of eyelid position. Statistical analyses were performed to identify the significance in the positional changes. All patients underwent orbital reconstruction through a transconjunctival incision by a single plastic surgeon. Results: In 42 blowout fracture patients, there was no statistical significant difference in the MRD2 and eyelash angle. Furthermore, there were no clinical complications, such as infection, hematoma, bleeding, or implant protrusion, during the follow-up periods. Conclusion: The advantages of the transconjunctival approach for orbital access include minimal scarring and a lower risk of eyelid displacement compared with other approaches. Based on these results, we recommend the transconjunctival approach for orbital exposure as a safe and reliable method.