• Title/Summary/Keyword: Major Axis

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Numerical Simulation Experiment on the Wind Ventilation Lane of the Local Circulation Winds in Daegu (대구지역의 국지적 대기순환풍의 환기경로에 관한 수치모의 실험)

  • Gu, Hyeon Suk;Kim, Hae Dong;Gang, Seong Dae
    • Journal of Environmental Science International
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    • v.13 no.4
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    • pp.367-376
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    • 2004
  • In urban area, thermal pollution associated with heat island phenomena is generally regarded to make urban life uncomfortable. To overcome this urban thermal pollution problem, urban planning with consideration of urban climate, represented by the concept of urban ventilation lane, is widely practiced in many countries. In this study, the prevailing wind ventilation lane of a local winds in Daegu during the warm climate season was investigated by using surface wind data and RAMS(Reasonal Atmospheric Model System) simulation. The domain of interest is the vicinity of Daegu metropolitan city(about 900 $km^{2})$ and its horizontal scale is about 30km. The simulations were conducted under the synoptic condition of late spring with the weak gradient wind and mostly clear sky. From the numerical simulations, the following two major conclusions were obtained: (1)The major wind passages of the local circulation wind generated by radiative cooling over the mountains(Mt. Palgong and Mt. Ap) are found. The winds blow down along the valley axis over the eastern part of the Daegu area as a gravity flow during nighttime. (2)After that time, the winds blow toward the western part of Daegu through the city center. As the result, the higher temperature region appears over the western part of Daegu metropolitan area.

Directional Control of Radiation Heat Transfer from Solid Surface Using Grating Composed of Parallel Elliptical Cylinders -Directional Control of Energy Concetration- (타원주격자를 사용한 고체면에서의 복사열전달의 방향제어-에너지 집중 방향제어-)

  • Go, Heung;Hidetoshi Masuda;Jo, Byeong Su;Gang, Yeong Gyu
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.9
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    • pp.2933-2943
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    • 1996
  • A grating composed of elliptical cylinders (GEC), specially designed, is applicable to control of radiation heat transfer from a heated surface, as reported in our previous work. In this study, an analysis of radiation heat transfer is performed for a physical model in which the GEC is placed in front of a heated black-base surface and the major axes of the elliptical cylinders are inclined as a certain angle from the normal to the row of elliptical cylinders. Numerical solutions are obtained. Variations of the direction and the radiative energy concentration with slant angle of the major axis are shown for some parameters. It is verified that the GEC is able to widely change the direction of radiation heat transfer from the heated surface.

ESTIMATION OF THE SGP4 DRAG TERM FROM TWO OSCULATING ORBIT STATES

  • Lee, Byoung-Sun;Park, Jae-Woo
    • Journal of Astronomy and Space Sciences
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    • v.20 no.1
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    • pp.11-20
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    • 2003
  • A method for estimating the NORAD SGP4 atmospheric drag term from minimum osculating orbit states, i.e., two osculating orbits, is developed. The first osculating orbit state is converted into the NORAD TLE-type mean orbit state by iterative procedure. Then the converted TLE is propagated to the second orbit state using the SGP4 model with the incremental SGP4 drag term. The iterative orbit propagation procedure is finished when the difference of the two osculating semi-major axes between the propagated orbit and the given second orbit is minimized. In order to minimize the effect of the short-term variations of the osculating semi-major axis, the osculating argument of latitude of the second orbit is propagated to the same argument of latitude of the first orbit. The method is applied to the estimation of the NORAD-type TLE for the KOMPSAT-1 spacecraft. The SGP4 drag terms are estimated from both NORAD SGP4 orbit propagation and the numerical orbit propagation results. Variations of the estimated drag terms are analyzed for the KOMPSAT-1 satellite orbit determination results.

A preparatory study on fish behavioral properties in a set-net

  • KANG, Myounghee;LIU, Jenming;HASSAN, Raja Bidin bin Raja;FAJARYANTI, Rina;HWANG, Bokyu
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.56 no.2
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    • pp.105-113
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    • 2020
  • The fish influx and behavioral properties at a set-net off Goseong, South Korea were investigated using an imaging sonar. As a result, the average influx of fish was 33.9% at day time and 66.1% at night time, respectively, which indicated that a majority of fish entered into a playground in the set-net at night. The fish behavioral properties such as target (fish) length, range, orientation and major-axis angle were examined and compared among survey dates (4, 5, and 6 June 2019) using the statistical analysis tool (analysis of variance, ANOVA). The behavioral properties presented differently sometime of survey dates. This is preparatory study to support fish behavior properties in a set-net. It is expected that more elaborated behavioral information of fishes in the set-net is beneficial for designing and deploying a set-net fishing gear as well as general fish behavior research in the future.

Design Study of LAR Tokamak Reactor with a Self-consistent System Analysis Code

  • Hong, B.G.;Lee, D.W.;Kim, S.K.;Kim, D.H.;Lee, Y.O.;Hwang, Y.S.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.314-314
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    • 2010
  • The design of the blanket and shield play a key role in determining the size of a reactor since it has an impact on the various reactor components. The blanket should produce enough tritium for tritium self-sufficiency and the shield should provide sufficient protection for the superconducting TF coil. Neutronic optimization of the blanket and the shield is necessary, and we coupled the system analysis with a neutronic calculation to account for the interrelation of the blanket and shield with the plasma performance of a reactor system in a self-consistent manner. By using the coupled system analysis code, the operational space for a low aspect ratio (LAR) tokamak reactor with a superconducting toroidal field (TF) coil is investigated with an spect ratio in the range of 1.5 - 2.5. The minimum major radius which satisfies all the physics and engineering requirements increases with the magnetic field at the magnetic axis. A required inboard shield thickness is mainly determined by the requirement on the protection of the TF coil against radiation damage. It is shown that to have a fusion power bigger than 3,000 MW in the LAR tokamak with a superconducting TF coil, a major radius bigger than 4.0 m is required.

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A Study on the 64 Trigrams in Major Books of Korean Medicine (한국 주요 의서(醫書)에 나타난 64卦에 대한 고찰(考察))

  • Baik, Yousang
    • Journal of Korean Medical classics
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    • v.35 no.1
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    • pp.155-172
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    • 2022
  • Objectives : Contents on the 64 trigrams in major medical texts from early to late Joseon such as the Uibangyuchwi(醫方類聚), Donguibogam(東醫寶鑑), Somundaeyo(素問大要), Gyeokchigo(格致藁) were analyzed to examine their characteristics and historical context. Methods : Related contents in each medical texts were collected, sorted and analyzed for thorough examination. Results : The study of Changes which was widely applied in the field of medicine throughout the Joseon period focused more heavily on each of the trigram patterns, especially in regards to the qi interaction between the upper and lower axis of the body, rather than the various meanings of the ten wings[十翼]. This is a result of the Jing-Qi-Shen perspective of the body and the universe that transcends the Daoist inner cultivation method[內丹術], under which concepts related to qi circulation such as the opening and closing[闔闢] of the Heaven[乾] and the Earth[坤], the interaction between Water[水] and Fire[火] were considered more important. Conclusions : The historical context of the study of medicine and Changes[易] of Korea could be grasped through analysing the 64 trigrams in medical texts of each period in Joseon. Further research with the field of History of Changes studies is much anticipated.

Developing a Job Exposure Matrix of Work Organization Hazards in the United States: A Review on Methodological Issues and Research Protocol

  • Choi, BongKyoo
    • Safety and Health at Work
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    • v.11 no.4
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    • pp.397-404
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    • 2020
  • Background: Most job exposure matrices (JEMs) have been developed for chemical and physical hazards in the United States (US). In addition, the overall validity of most JEMs of work organization hazards using self-reported data in the literature remains to be further tested due to several methodological weaknesses. Methods: This paper aims to review important methodological issues with regard to a JEM of work organization hazards using self-report data and to present a research protocol for developing a four-axis (job titles, hazards, sex, and time) JEM of major work organization hazards using the US General Social Survey-Quality of Work-Life (GSS-QWL) data (2002-2018; N = 7,100 workers). Results: Five methodological weaknesses in existing JEMs of work organization hazards using self-report data were identified: having only two axes (hazard and occupation), using psychometrically weak items and scales, including scales having little interoccupational variability, unresolved optimal minimum numbers of subjects per occupation, and low accessibility. The methodological weaknesses were successfully addressed in the proposed research protocol. Conclusion: The work organization JEM to be developed will significantly facilitate and strengthen occupational epidemiological studies on work organization hazards and major health outcomes, improve national and occupational surveillance of work organization hazards, and promote interventions for a healthy work environment in the US.

Image Color, Brightness, Saturation Similarity Validation Study of Emotion Computing (이미지 색상, 명도, 채도 감성컴퓨팅의 유사성 검증 연구)

  • Lee, Yean-Ran
    • Cartoon and Animation Studies
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    • s.40
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    • pp.477-496
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    • 2015
  • Emotional awareness is the image of a person is represented by different tendencies. Currently, the emotion computing to objectively evaluate the emotion recognition research is being actively studied. However, existing emotional computing research has many problems to run. First, the non-objective in emotion recognition if it is inaccurate. Second, the correlation between the emotion recognition is unclear points. So to test the regularity of image sensitivity to the need of the present study is to control emotions in the computing system. In addition, the screen number of the emotion recognized for the purpose of this study, applying the method of objective image emotional computing system and compared with a similar degree of emotion of the person. The key features of the image emotional computing system calculates the emotion recognized as numbered digital form. And to study the background of emotion computing is a key advantage of the effect of the James A. Russell for digitization of emotion (Core Affect). Pleasure emotions about the core axis (X axis) of pleasure and displeasure, tension (Y-axis) axis of tension and relaxation of emotion, emotion is applied to the computing research. Emotional axis with associated representative sensibility very happy, excited, elated, happy, contentment, calm, relaxing, quiet, tired, helpless, depressed, sad, angry, stress, anxiety, pieces 16 of tense emotional separated by a sensibility ComputingIt applies. Course of the present study is to use the color of the color key elements of the image computing formula sensitivity, brightness, and saturation applied to the sensitivity property elements. Property and calculating the rate sensitivity factors are applied to the importance weight, measured by free-level sensitivity score (X-axis) and the tension (Y-axis). Emotion won again expanded on the basis of emotion crossed point, and included a representative selection in Sensibility size of the top five ranking representative of the main emotion. In addition, measuring the emotional image of a person with 16 representative emotional score, and separated by a representative of the top five senses. Compare the main representative of the main representatives of Emotion and Sensibility people aware of the sensitivity of the results to verify the similarity degree computing emotion emotional emotions depending on the number of representative matches. The emotional similarity computing results represent the average concordance rate of major sensitivity was 51%, representing 2.5 sensibilities were consistent with the person's emotion recognition. Similar measures were the degree of emotion computing calculation and emotion recognition in this study who were given the objective criteria of the sensitivity calculation. Future research will need to be maintained weight room and the study of the emotional equation of a higher concordance rate improved.

The morphological and chemical composition characteristics of Opuntia ficus-indica and Opuntia humifusa fruits (손바닥선인장(백년초, 천년초) 열매의 외관 및 성분특성 연구)

  • Kim, Mi-Hyun;Kim, Hee Jung;Jang, Mi;Lim, Tae-Gyu;Hong, Hee-Do;Rhee, Young Kyoung;Kim, Kyung-Tack;Cho, Chang-Won
    • Food Science and Preservation
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    • v.23 no.5
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    • pp.711-717
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    • 2016
  • Opuntia humifusa fruits were investigated. The length of minor and major axis, and weight of O. ficus-indica and O. humifusa fruits were compared as the morphological features. The characteristics of components such as color, moisture, crude protein, ash, fat, dietary fiber, mineral, and amino acids were evaluated. The values of O. ficus-indica fruits were higher than those of O. humifusa fruits in each morphological feature such as minor axis, major axis, and weight. According to the Hunter color index results, O. humifusa fruits showed higher values of L (lightness) and b (yellowness), whereas O. ficus-indica fruits showed higher value of a (redness). The ${\Delta}E$ value between two samples was 19.80. The O. ficus-indica fruits had higher carbohydrate content and lower content of crude ash than those of O. humifusa fruits. Both samples showed very high dietary fiber contents, and the major minerals were K and Ca. Glutamic acid was the major amino acids in both samples. In free amino acids contents, O. ficus-indica had higher tyrosine and lower glutamic acid level than those of O. humifusa fruits. ${\gamma}$-aminobutyric acid was found in both samples, whereas taurine was found in O. ficus-indica fruits only. Taken together, the morphological features and chemical quality of O. ficus-indica and O. humifusa fruits showed difference although both of them were originated from the same genus.

Optimal Estimation (OE) Technique to Retrieve the Ozone Column and Tropospheric Ozone Profile Based on Ground-based MAX-DOAS Measurement (오존전량 및 대류권 오존 프로파일 산출을 위한 지상관측 MAX-DOAS 원시자료 기반의 최적추정(Optimal Estimation) 기술)

  • Park, Junsung;Hong, Hyunkee;Choi, Wonei;Kim, Daewon;Yang, Jiwon;Kang, Hyungwoo;Lee, Hanlim
    • Korean Journal of Remote Sensing
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    • v.34 no.2_1
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    • pp.191-201
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    • 2018
  • In this present study, we, for the first time, retrieved total column of ozone ($O_3$) and tropospheric ozone vertical profile using the Optimal Estimation (OE) method based on the MAX-DOAS measurement at the Yonsei University in Seoul, Korea. The optical density fitting is carried out using the OE method to calculate ozone columns. The optical density between the MAX-DOAS data obtained by dividing the measured intensities for each viewing elevated angle by those at the zenith angle. The retrieved total columns of the ozone are 375.4 and 412.6 DU in the morning (08:13) and afternoon (17:55) on 23 May, 2017, respectively. In addition, under 10 km altitude, the $O_3$ vertical profile was retrieved with about 5% of retrieval uncertainty. However, above 10 km altitude, the $O_3$ vertical profile retrieval uncertainty was increased (>10%). The spectral fitting errors are 16.8% and 19.1% in the morning and afternoon, respectively. The method suggested in this present study can be useful to measure the total ozone column using the ground-based hyper-spectral UV sensors.