• Title/Summary/Keyword: Extreme Points

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Analysis of ASEAN's Stock Returns and/or Volatility Distribution under the Impact of the Chinese EPU: Evidence Based on Conditional Kernel Density Approach

  • Mohib Ur Rahman;Irfan Ullah;Aurang Zeb
    • East Asian Economic Review
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    • v.27 no.1
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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.

Helium guard system design for HIAF iLinac cryogenic distribution system

  • Xianjin Wang;Shuping Chen;Wen Jun;Dajun Fan;Liming Zhu;Yanan Lib;Xiaofei Niu;Junhui Zhang
    • Progress in Superconductivity and Cryogenics
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    • v.25 no.1
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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.

Comparative Performance Analysis of Feature Detection and Matching Methods for Lunar Terrain Images (달 지형 영상에서 특징점 검출 및 정합 기법의 성능 비교 분석)

  • Hong, Sungchul;Shin, Hyu-Soung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.40 no.4
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    • pp.437-444
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    • 2020
  • A lunar rover's optical camera is used to provide navigation and terrain information in an exploration zone. However, due to the scant presence of atmosphere, the Moon has homogeneous terrain with dark soil. Also, in extreme environments, the rover has limited data storage with low computation capability. Thus, for successful exploration, it is required to examine feature detection and matching methods which are robust to lunar terrain and environmental characteristics. In this research, SIFT, SURF, BRISK, ORB, and AKAZE are comparatively analyzed with lunar terrain images from a lunar rover. Experimental results show that SIFT and AKAZE are most robust for lunar terrain characteristics. AKAZE detects less quantity of feature points than SIFT, but feature points are detected and matched with high precision and the least computational cost. AKAZE is adequate for fast and accurate navigation information. Although SIFT has the highest computational cost, the largest quantity of feature points are stably detected and matched. The rover periodically sends terrain images to Earth. Thus, SIFT is suitable for global 3D terrain map construction in that a large amount of terrain images can be processed on Earth. Study results are expected to provide a guideline to utilize feature detection and matching methods for future lunar exploration rovers.

Robust Designs of the Second Order Response Surface Model in a Mixture (2차 혼합물 반응표면 모형에서의 강건한 실험 설계)

  • Lim, Yong-Bin
    • The Korean Journal of Applied Statistics
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    • v.20 no.2
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    • pp.267-280
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    • 2007
  • Various single-valued design optimality criteria such as D-, G-, and V-optimality are used often in constructing optimal experimental designs for mixture experiments in a constrained region R where lower and upper bound constraints are imposed on the ingredients proportions. Even though they are optimal in the strict sense of particular optimality criterion used, it is known that their performance is unsatisfactory with respect to the prediction capability over a constrained region. (Vining et at., 1993; Khuri et at., 1999) We assume the quadratic polynomial model as the mixture response surface model and are interested in finding efficient designs in the constrained design space for a mixture. In this paper, we make an expanded list of candidate design points by adding interior points to the extreme vertices, edge midpoints, constrained face centroids and the overall centroid. Then, we want to propose a robust design with respect to D-optimality, G-optimality, V-optimality and distance-based U-optimality. Comparing scaled prediction variance quantile plots (SPVQP) of robust designs with that of recommended designs in Khuri et al. (1999) and Vining et al. (1993) in the well-known examples of a four-component fertilizer experiment as well as McLean and Anderson's Railroad Flare Experiment, robust designs turned out to be superior to those recommended designs.

A COMPARATIVE STUDY OF THE AMOUNT OF DISPLACEMENT AND OCCLUSION FORMS IN THE CHANGE FROM CR TO CO (중심위 교합에서 중심 교합으로 전위될 때의 변위량과 교합형태에 관한 비교 연구)

  • Lee, Jae-Bong;Shin, Cheol-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.45 no.1
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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.

The Selection of Optimal Probability Distribution and Estimation for Design Hourly Factor in National Highway Roads (일반국도 설계시간계수의 적정 확률분포 선정 및 추정)

  • Jo, Jun-Han;Han, Jong-Hyeon;Kim, Seong-Ho;Lee, Byeong-Saeng
    • Journal of Korean Society of Transportation
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    • v.24 no.6 s.92
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    • pp.33-43
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    • 2006
  • This research is to the selection of optimal probability distribution as well as the estimation for design hourly factor in consideration of traffic characteristic, such as road function, lane number and AADT. To accomplish the objectives, we are applied to various probability distribution using traffic data that observed at permanent traffic count points in 2005. The parameters or the selected 14 probability distribution were estimated based on the method of maximum likelihood and the validity condition of the estimated parameter The goodness-of-fit test, such as chi-square test. was performed as well as the estimation of design hourly factor. As a result, An appropriate distributions of each case were selected : Pearson V for two lane of rural roads, LogLogistic for the four lane of rural roads, LogLogistic for the urban roads, Extreme value for recreation roads. And optimal K factor are as following : $0.1{\sim}0.2 $ for two lane of rural roads, $0.09{\sim}0.14$ for the four lane of rural roads. $0.07{\sim}0.13$ for the urban roads, $0.1{\sim}0.2$ for recreation roads.

Changes in the Spatiotemporal Patterns of Precipitation Due to Climate Change (기후변화에 따른 강수량의 시공간적 발생 패턴의 변화 분석)

  • Kim, Dae-Jun;Kang, DaeGyoon;Park, Joo-Hyeon;Kim, Jin-Hee;Kim, Yongseok
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.23 no.4
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    • pp.424-433
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    • 2021
  • Recent climate change has caused abnormal weather phenomena all over the world and a lot of damage in many fields of society. Particularly, a lot of recent damages were due to extreme precipitation, such as torrential downpour or drought. The objective of this study was to analyze the temporal and spatial changes in the precipitation pattern in South Korea. To achieve this objective, this study selected some of the precipitation indices suggested in previous studies to compare the temporal characteristics of precipitation induced by climate change. This study selected ten ASOS observatories of the Korea Meteorological Administration to understand the change over time for each location with considering regional distribution. This study also collected daily cumulative precipitation from 1951 to 2020 for each point. Additionally, this study generated high-resolution national daily precipitation distribution maps using an orographic precipitation model from 1981 to 2020 and analyzed them. Temporal analysis showed that although annual cumulative precipitation revealed an increasing trend from the past to the present. The number of precipitation days showed a decreasing trend at most observation points, but the number of torrential downpour days revealed an increasing trend. Spatially, the number of precipitation days and the number of torrential downpour days decreased in many areas over time, and this pattern was prominent in the central region. The precipitation pattern of South Korea can be summarized as the fewer precipitation days and larger daily precipitation over time.

FRICTION UNITS FOR THE MOON

  • Drozdov, Yu.N.
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.10b
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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.

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The Effect of Sport Drink Ingestion on the Physical Fatigue Level and Heart Rate during Prolonged Exposure in Hot Ambient Temperature in Professional Golfers (장시간 고온 환경 노출시 수분의 섭취가 프로골프선수들의 신체피로도 및 심박수에 미치는 영향)

  • Kim Seung-Kon;Cho In-Ho;Park Soo-Yeon;Lee Jong-Sam
    • Journal of Nutrition and Health
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    • v.38 no.2
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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)

A Study on The Grotesque Make-up in the Late 1990′s - Focused on Make-up Advertisements and Collections - (1990년대 후반 그로테스크 메이크업에 관한 연구 - 메이크업 광고와 컬렉션을 중심으로 -)

  • 장미숙;양숙희
    • The Research Journal of the Costume Culture
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    • v.8 no.3
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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.

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