• East Asian Economic Review
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• 제27권1호
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• pp.33-60
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• 2023

This paper analyzes the entire distribution of stock market returns/volatility in five emerging markets (ASEAN5) and figures out the conditional distribution of the CHI_EPU index. The aim is to examine the impact of CHI_EPU on the stock returns/volatility density of ASEAN5 markets. It also examined whether changes in CHI_EPU explain returns at higher or lower points (abnormal returns). This paper models the behaviour of stock returns from March 2011 to June 2018 using a non-parametric conditional density estimation approach. The results indicate that CHI_EPU diminishes stock returns and augments volatility in ASEAN5 markets, except for Malaysia, where it affects stock returns positively. The possible reason for this positive impact is that EPU is not the leading factor reducing Malaysian stock returns; but, other forces, such as dependency on other countries' stock markets and global factors, may have a positive impact on stock returns (Bachmann and Bayer, 2013). Thus, the risk of simultaneous investment in Chinese and ASEAN5 stock markets, except Malaysia, is high. Further, the degree of this influence intensifies at extreme high/low intervals (positive/negative tails). The findings of this study have significant implications for investors, policymakers, market agents, and analysts of ASEAN5.

• 한국초전도ㆍ저온공학회논문지
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• 제25권1호
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• pp.6-10
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• 2023

2 K superfluid helium cryogenic system is the crucial component of many large accelerators. When the cryogenic system is operating at 2K@3129Pa, many room-temperature parts are connected to superfluid helium via tubes. Air Leakage in these connections may lead to air contamination of the cryogenic system. Air contamination may cause equipment failure in cryogenic systems and, in extreme cases, render the entire accelerator system inoperable. Helium guard is a technique that guards against air contamination of these sub-atmospheric pressure connections in 2 K superfluid helium cryogenic system. This paper introduces a typical 2 K cryogenic distribution design for large accelerators, and make risk analysis of air contamination. Finally, the analysis of specific leakage points and detailed engineering design are presented, which may be used as a reference when designing of a 2 K superfluid helium cryogenic distribution system.

• 대한토목학회논문집
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• 제40권4호
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• pp.437-444
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• 2020

달 로버의 광학 카메라는 로버의 주행정보와 탐사 지역의 3차원 지형정보를 제공한다. 하지만 대기가 없는 달은 단조로운 지형과 어두운 색조의 토양으로 구성되며, 달의 혹독한 환경에서 로버는 낮은 데이터 저장 용량과 연산 성능을 가진다. 따라서 로버의 안전한 주행과 성공적인 달 탐사를 위해서는 달의 지형 및 환경 특성에 강인한 특징점 검출 및 정합 기법 사용이 검토되어야 한다. 본 연구에서는 달 탐사 로버가 취득한 지형 영상을 대상으로 SIFT, SURF, BRISK, ORB, AKAZE들의 성능을 비교 분석하였다. 실험 결과 SIFT와 AKAZE가 달 지형 특성에 강인한 성능을 보여 주었다. AKAZE는 SIFT에 비해 적은 개수의 영상 정합점들을 검출하였으나, 높은 정확도를 가지며 가장 빠르게 영상 정합점들을 검출하였다. 따라서 정확하고 신속한 연산이 필요한 로버 주행 정보 생성에 적합하다. SIFT는 가장 무거운 연산 속도를 보이나, 가장 많은 영상 정합점들을 안정적으로 검출하였다. 달 탐사 로버는 주기적으로 지형 영상을 지구로 전송한다. 따라서 많은 양의 지형 영상을 처리할 수 있는 지구에서 3차원 지형도 구축을 위해 사용하는 것이 적합하다. 본 연구 결과는 향후 달 탐사 로버에서 특징점 검출 기법들의 활용을 위한 가이드라인을 제공할 수 있을 것으로 기대된다.

• 응용통계연구
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• 제20권2호
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• pp.267-280
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• 2007

혼합물 성분들의 비율의 상한과 하한에 대한제한조건이 부과된 제한된 혼합물 실험 공간 R에서의 혼합물 실험을 위한 최적 설계를 찾는 데에 D-, G-, V- 최적기준 등과 같은 다양한 최적 설계 기준이 사용된다. 각각의 실험 설계는 선택된 최적 기준에 대해서는 최적이지만, 제한된 혼합물 실험 공간에서의 예측력에 대해서는 만족스럽지 못하다는 것은 잘 알려진 사실이다. (Vining 등, 1993; Khuri 등, 1999). 우리의 관심사는 2차 혼합물 반응표면모형을 가정한 경우에 제한된 혼합물 공간에서의 효율적인 실험 설계를 찾는 것이다. 이 논문에서는 꼭지점, 선중심점, 면중심점, 중앙점과 내부점으로 구성된 확장된 후보 실험점 그룹을 구성한 다음에, D-최적기준, G-최적기준, V-최적기준과 실험점들 간의 거리에 근거한 U-최적기준에 강건한 실험 설계를 제안한다. Khuri 등(1999)에서 분석된 비료 혼합물 실험과Vining과 Cornell(1993)이 분석한 조명탄 혼합물 실험의 사례에서 강건한 실험설계들과 두 논문에서 추천된 실험 설계들에 대한 예측치의 표준화된 분산의 분위수의 그림(SVPQP)을 비교한 결과 강건한 설계가 상대적으로 우월함이 판명되었다.

• 대한치과보철학회지
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• 제45권1호
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• pp.1-11
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• 2007

Statement of problems: The concept of CR has also changed continuously.?In order to find out the factors that affect the centric slide, studies were carried out to compare the forms of wisdom teeth eruption, lateral movement, premature contact in CR, and anterior movement. Research and statistical methods were based on the report by the 1980 Korean dental association. Material and method: In our study, 403 dentists in their twenties and dentistry students who could understand CR and CO (and who did not receive occlusal, orthodontic treatment, without extreme caries and large prosthodontic care) were compared with the 25 year old results. A segment of line parallel to the upper incisor was marked on the lower incisor. When seen laterally, a line perpendicular to the occlusal plane was drawn on the foremost area of the upper incisor. This line was extended to the lower incisor and the two points (points at the lower and upper incisors) were used as reference points for the CO. After guiding the occlusion to the CR, two lines were marked by using the same method that was used for the CO. The point in which these lines meet became the reference point of CR occlusion Results and conclusions: Results of the experiment completed in 1980 show that all 307 research members had anterior-posterior and upper-lower displacement. Displacement measurements were $0.7{\pm}0.4mm$ for the anterior-posterior displacement, $0.99{\pm}0.50mm$ for the upper-lower displacement,0.18{\pm}0.31 mm for the lateral displacement, and $1.32{\pm}0.67mm$ for the total displacement. Results of the 2006 experiment show that all 409 research members had anterior-posterior and upper-lower displacement. The anterior-posterior displacement was $1.12{\pm}0.86mm$, the upper-lower displacement was $1.02{\pm}0.71mm$, the lateral displacement was $0.61{\pm}0.56mm$, and the total displacement was $1.80{\pm}0.99mm$. No specific differences were found between each group when comparing displacement according to the forms of wisdom teeth eruption. Since 1980, the percentage of unerupted teeth has increased from 35.16% (111/307 people) to 57.5% (236/409 people). Westernization of the Korean cranial form and intraoral structure has brought about these results. In our experiment, 26.7% (109/409 people) of the subjects were cuspid guided, while 7.3% (30/409 people) were mutually guided. No specific differences were found in the amount of displacement between the two groups. Only the subjects with anteriors coming in contact made up the largest percentage group (42.3%, 173/409 people) in our study. No specific differences were found between each group.

• 대한교통학회지
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• 제24권6호
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• pp.33-43
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• 2006

본 연구는 도로의 기능 및 통행특성. 차로수, 연평균일교통량 등을 고려하여 설계시간계수와의 관계를 살펴보고 적정 확률분포형 선정과 K값을 추정하였다 이를 위해 2005년도 상시 교통량 조사지점에서 수집된 교통자료를 이용하여 14개의 확률분포형을 적용하였다. 각 확률분포형은 최우도법을 이용하여 매개변수를 추정하였으며 각 분포형별로 매개변수 적합성 조건을 검토하였다. 적정 확률분포형의 결정은 chi-square검정을 통하여 대상 분포형의 기각유무를 판단하였으며. 그 결과에 대해 우선순위를 정하여 적정 확률분포형을 선정하였다. 그리고 각 유형별 AADT에 따른 적정 K계수를 추정하였다. 그 결과, 지방부 2차로 및 4차로. 도시부, 관광부도로의 적정 확률분포형은 각각 Pearson V, LogLogistic, LogLogistic, Extreme value 분포로 분석되었으며 적정 K계수는 각각 $0.1{\sim}0.2,\;0.09{\sim}0.14,\;0.07{\sim}0.13,\;0.1{\sim}0.2$로 추정되었다.

• 한국농림기상학회지
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• 제23권4호
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• pp.424-433
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• 2021

최근의 기후변화는 지구촌 곳곳에 이상기상 현상을 발생시키며, 사회 여러 분야에서 많은 피해를 발생시키고 있다. 특히 최근에는 호우 또는 가뭄 등 강수량의 많고 적음으로 인한 피해가 많이 보고되고 있는데, 본 연구에서는 실제로 우리나라에서 발생하고 있는 강수량의 발생 패턴을 조사하여 과거에서 현재까지 어떤 변화를 보이는지 분석해보고자 하였다. 이를 위해 선행연구에서 기후변화에 따른 강수량의 시간적 특성 비교를 위해 제시한 강수지표 중 일부를 선정하였다. 지점별 시간에 따른 변화를 분석하기 위하여 국내 기상청 ASOS 관측소 10개 지점을 지역분포를 고려하여 선정하였으며, 지점별로 1951년부터 2020년까지의 일적산강수량을 수집하였다. 또한 산악강수모형을 이용하여 1981년부터 2020년까지의 전국 고해상도의 일별 강수분포도를 제작하여 분석에 활용하였다. 시간에 따른 분석결과 연적산강수량의 경우 과거에서 현재로 이동하면서 증가 양상을 보였다. 강수일수의 경우 대부분의 관측지점에서 감소하는 추세를 보였으며, 호우일수의 경우는 반대로 증가하는 경향을 보였다. 공간적인 변화의 경우 강수일수와 호우일수 모두 과거에 비해 감소되는 지역이 많았으며, 그 특징은 중부지방에서 두드러지게 나타났다. 결과적으로 우리나라의 강수량의 패턴은 짧아진 강수일수, 늘어난 일별 강수량으로의 변화로 정리할 수 있다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.389-396
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• 2002

In XXI century it is necessary to expect the recommencement and development of activities on mastering the Moon. In the long term it is construction of manned lunar bases with industrial, astrophysical, procuring, repair equipment and services. Interplanetary flights from the Moon demand smaller power expenditures, than from the Earth, therefore it is favourable to use its surface for the construction of space-vehicle launching sites. Flights of devices in libration points in the system 'Earth - Moon' are considered. Experience of engineering system creation for the Moon displays the great complexity in provision of serviceability and reliability of friction units. Open friction units should operate under following conditions on the Moon: pressure of environment (vacuum) $p\;>10\;^{-10}$ Pa; wide range of temperature change $+150^{\circ}C\;...170^{\circ}C$; high evaporability of lubricants; influence of temperature gradients and warping of constructions; sublimation of elements of constructional materials; irradiation of different physical nature; effect of micrometeorites; reduced gravitation; influence of abrasive particles of lunar ground; requirements on minimization of size and weight characteristics of a construction (high tension); undesirability (impossibility) of application of liquid and plastic lubricants; vibration, shock, acoustic loadings during start and landings to the Earth; difficulties in repair-regenerative operations in conditions of the Moon etc. Adhesive interaction of conjugated surfaces is the principal reason of possible failures of rubbed units on the Moon. In the research of the Moon automatic interplanetary stations of 'Luna' (USSR), 'Surveyer', 'Apollo' (USA) series were used. Stations executed functions of flying, landing, artificial satellites of the Moon, moon-rovers and manned spacecrafts such as 'Apollo'. The experimental- theoretical researches carried out in the sixtieth years on tribology for conditions of the Moon appeared to be rather useful to engineering of an outer space exploration and the decision of complex problems for the friction units operating in extreme conditions on the Earth. For the creation of highly loaded friction units for the long service life on the Moon it is required not only to use accumulated experience and designed technologies, but also to carry out wide scientific research.

• Journal of Nutrition and Health
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• 제38권2호
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• pp.117-124
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• 2005

We investigated the effects of prolonged exposure in hot environmental condition and ingestion of fluid on various physiological variables including plasma glucose, lactate, the rating of perceived exertion (RPE), and heart rate as well as golf putting performance. Six male professional golfers were voluntarily participated in three different putting trials which were separated by seven days of time interval period. Three different putting trials were conducted at either 20℃ or 32℃, or 32℃ + Fluid ingestion. Performing 32℃ + Fluid ingestion trial, all subject ingested sport drink as much as their body mass was decreased. For each experiment, all subjects were undertaken total 48 putting, which separated by four x 12 putting in four different time points (i.e., Rest, 1 hr, 2 hr, and 3 hr). Plasma glucose concentration was significantly decreased with hot ambient condition but it was almost fully recovered by fluid ingestion. Plasma lactate concentration was significantly higher when subjects were exposed in hot environmental condition, and it did not change with fluid ingestion. There was a no different in putting performance and psychological fatigue level (performed by GRID test) at any environmental conditions. The RPE, commonly used for evaluating of physical fatigue level, was significantly dropped by fluid ingestion which indicates lower physical fatigue level. In addition to this, heart rate (HR) was also significantly decreased after fluid ingestion. Based on these results, it was concluded that the ingestion of fluid during prolonged exposure in hot ambient condition decrease the degree of physical fatigue levels and heart rate, which will possibly improve the golf performance when exposed in extreme weather condition in summer. (Korean J Nutrition 38(2): 117～124, 2005)

• 복식문화연구
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• 제8권3호
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• pp.436-499
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• 2000

The purpose of this study is to be inquired social and cultural significance of the Grotesque phenomenon in the late 1990's make-up, as well as its experimentalism and avantgardism. The Grotesque is the aesthetic concept, which is composed of ambivalent structure of humor and horror, interest and disgust through join of heterogenous factors, distortion, extreme and overstatement in the patterns and materials of make-up. The Grotesque in the modern make-up is represented in the make-up advertisements and collections. In this paper, the author classified the Grotesque phenomenon with the Kitsch, the Machine, the Animal and the Devil, focused on heterogenous factors. The results are as follows. 1. The Kitsch in the make-up uses not cosmetics but imitations, ready-made goods, and ordinary materials. It expresses modern culture's laziness through shocking self-expression. 2. The Machine in the make-up means silver or white color's make-up, and represents cyber period's arrival through contrary irony, loss of the human value and the personifications of machine. At the same time, it is understood as the curing of human alinetion. 3. The Animal in the make-up utilizes the wild animal's horn, the reptiles'sputum, and the legend's animal. It points out a human false virtual image, and overturns make-up's traditional aesthetic concept. 4. The Devil in the make-up shows vampire's cuspid, demon's horn, artificial nail, and black color's make-up. It raises social irrationality and discrepancy of capitalism, and expresses paradoxically the nature of human life. The Devil in the make-up expresses the creator's innovation, anxiety of fin-de-siecle, and simultaneously criticizes and cures confused reality. It shows also avantgarde implementation of dissolution of traditional aesthetic concept and acceptance ugliness.