• Title/Summary/Keyword: separation

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Properties of microlensing events of wide-separation planets with a moon

  • Chung, Sun-Ju;Ryu, Yoon-Hyun
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.57.4-58
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    • 2015
  • Thanks to high cadence monitoring and high photometric accuracy of Korea Microlensing Telescope Network (KMTNet), we expect the detection of many events caused by wide-separation planets and free-floating planets, which is not easy due to the short event duration. Thus, it is important to understand wide-separation planetary lensing events. Several studies on the wide-separation events have been reported, but events caused by wide-separation planetary systems with a moon have not yet been studied. In this paper, we study the properties of events caused by planetary systems where wide-separation planets host a moon. We also study the effect of a finite background source star on the moon feature in the wide planetary-lensing events.

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Pyroshock Prediction of the Satellite Launch Vehicle at the Payload Fairing Separation (인공위성 발사체 노즈페어링 분리 시 구조물의 충격량 예측)

  • Jeong, Ho-Kyeong;Youn, Se-Hyun;Park, Soon-Hong;Jang, Young-Soon;Lee, Yeoung-Moo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.250-253
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    • 2005
  • This paper is investigates the separation shock of payload fairing. Separation test of subscale PLF using half separation device and half PLA is performed. Resulting shock loads at equipment bay and fairing joint are measured. Pyroshock estimation is performed using AUTOSEA Pyroshock Module. Input data to analysis model is obtained from the separation test results of subscale PLF. And model of AUTOSEA is updated comparing results between tests and analysis.. This enables us to validate the AUTOSEA model. Tuned model of subscale PLF and separation device is used to update full scale model, and the shock analysis result of full scale model is estimated in this paper. This paper also discusses the results regarding the difficulty of structural modeling and its numerical implementation in AutoSEA2 Software.

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Evaluation of the Effective Charge Density on Low Pressure Nanofiltration with the Separation Characteristics of Monovalent and Divalent Solutes in the Production of Drinking Water

  • Oh, Jeong-Ik;Taro, Urase
    • Environmental Engineering Research
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    • v.16 no.1
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    • pp.29-34
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    • 2011
  • The electric charge on a membrane was investigated by analyzing the experimental rejection of various monovalent and divalent ionic solutes. The characteristics of the separation of ionic solutes using various nanofiltration membranes were obtained from an experimental nanofiltration set-up, with a surface area of $40cm^2$ under the operational pressures between 0.25-0.3 MPa. The state of the membrane electric charge was observed using separation coefficients, i.e., the permeation ratio of monovalent to divalent ions. To confirm the state of the membrane charge observed via the separation coefficient, a calculation using the extended Nernst-Planck equation, coupled with the Donnan equilibrium, assuming different electric charge states of the membrane, was compared with the experimental rejection of ionic solutes. The examination of the characteristics of separation using three types of nanofiltration membranes showed that one of the membranes carried a negative/positive double charge density inside, while other two membranes carried either a positive or negative charge density.

On the Separation of the Rank-1 Chvatal-Gomory Inequalities for the Fixed-Charge 0-1 Knapsack Problem (고정비용 0-1 배낭문제에 대한 크바탈-고모리 부등식의 분리문제에 관한 연구)

  • Park, Kyung-Chul;Lee, Kyung-Sik
    • Journal of the Korean Operations Research and Management Science Society
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    • v.36 no.2
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    • pp.43-50
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    • 2011
  • We consider the separation problem of the rank-1 Chvatal-Gomory (C-G) inequalities for the 0-1 knapsack problem with the knapsack capacity defined by an additional binary variable, which we call the fixed-charge 0-1 knapsack problem. We analyze the structural properties of the optimal solutions to the separation problem and show that the separation problem can be solved in pseudo-polynomial time. By using the result, we also show that the existence of a pseudo-polynomial time algorithm for the separation problem of the rank-1 C-G inequalities of the ordinary 0-1 knapsack problem.

A Study on Separation Distance between Industrial Source and Residential Areas to Avoid Odor Annoyance Using AUSPLUME Model (AUSPLUME 모델을 이용한 악취를 피하기 위한 산업오염원과 주거단지 사이 이격거리에 관한 연구)

  • 정상진
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.5
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    • pp.393-400
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    • 2002
  • Separation distance between industrial source and residential areas to avoid odor annoyance was investigated using AUSPLUME model. A Gaussian plume model (AUSPLUME) for the dispersion was used to calculate odor emission from ground level area source. Using the dispersion model to calculate ambient odor concentrations, the separation distance between industrial source and residental areas was defined by %HA (percentage of highly annoyed person) and odor percentile concentration (C98). The result was compared with the separation distance of various nation guidelines for livestock buildings. The calculated separation distance for industrial source showed similar pattern comparing with various guidelines for livestock buildings.

A Computational Study on the Unsteady Lateral Loads in a Rocket Nozzle

  • Nagdewe, Suryakant;Kim, Heuy-Dong
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.05a
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    • pp.289-292
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    • 2008
  • Highly over-expanded nozzle of the rocket engines will be excited by non-axial forces due to flow separation at sea level operations. Since rocket engines are designed to produce axial thrust to power the vehicle, non-axial static and/or dynamic forces are not desirable. Several engine failures were attributed to the side loads. Present work investigate the unsteady flow in an over-expanded rocket nozzle in order to estimate side load during a shutdown/starting. Numerical computations has been carried out with density based solver on multi-block structured grid. Present solver is explicit in time and unsteady time step is calculated using dual time step approach. AUSMDV is considered as a numerical scheme for the flux calculations. One equation Spalart-Allmaras turbulence model is selected. Results presented here is for two nozzle pressure ratio i.e. 100 and 20. At 100 NPR, restricted shock separation (RSS) pattern is observed while, 20 NPR shows free shock separation (FSS) pattern. Side load is observed during the transition of separation pattern at different NPR.

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The Effects of Psychological Separation from Parents and Family Adaptability on Child's Adjustment to College (부모와의 심리적 독립과 가족의 적응성이 자녀의 대학 생활 적응에 미치는 영향)

  • Cho, Yoon-Joo
    • Journal of Families and Better Life
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    • v.28 no.2
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    • pp.17-26
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    • 2010
  • This study aimed to explore psychological separation from parents, family adaptability, and child's adjustment to college, in order to assess general standards and sex difference. It also investigated explaining variables on children's adjustment to college. The study subjects were 243 college students(male students; 123, female students; 120).The data collected from questionnaire were analyzed by descriptive statistics, t test, Pearson's correlation and hierarchical multiple regression. The main results were as follows: Firstly, psychological separation from parents of college students were lower than those of average score. But family adaptability and adjustment to college of students were higher than those of average score. Secondly, psychological separation from parents was negatively correlated to adjustment to college, but family adaptability was positively correlated to adjustment to college. Finally, variables that explain child's adjustment to college was cohavitation with parents and family adaptability. In addition to these variables, psychological separation from parents was a major factor for female students.

Phase Separation and their Structures in $BaO-B_2O_3$ Glasses ($BaO-B_2O_3$계 유리의 상분리 현상과 유리의 구조)

  • 채수철;김철영
    • Journal of the Korean Ceramic Society
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    • v.23 no.6
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    • pp.25-32
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    • 1986
  • Phase spearated glass is heterogeneous in microscopic point of view and the heterogeneities affect the structures of glasses. In the present work the phase separation of $BaO-B_2O_3$ glass system was investigated and the effect of $P_2O_5$ on the phase separation and crystallization was also studied in the above system. Experiments such as scanning electron microscopy X-ray diffraction and infrared spectroscopy were performed. Phase separation with $B_2O_3$ rich phase matrix and BaO rich phase droplet was observed for the glasses containing less than 6 mole% of BaO while the opposite morphology of phase separation was found for the glasses containing more than 7 mole% of BaO. Phase separation region was extended up to the glass with 22mole% of BaO when the amount of $P_2O_5$ was increased. The heat-treated glasses crystallized to BaO.$4B_2O_3$$P_2O_5$ hindered the glass from the crystalli-zation.

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The removal of iron oxides from raw materials by superconducting magnetic separator (초전도 자기분리에 의한 원재료에서의 철산화물 제거)

  • Kwon, Jun-Mo;Ha, Dong-Woo;Kim, Tae-Hyung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.193-193
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    • 2010
  • Magnetic separation is expected to be applied for material refinement as an important supporting technology. In the superconducting magnetic separation, the cohesive force between particles is strong compared with that in the other magnetic separation. The use of high magnetic field by the superconducting magnet enhances the magnetic substance capture ability of the magnetic separation. Industrial raw materials was used for the superconducting magnetic separation. Cry-cooled, NB-Ti superconducting magnet with. 100 mm room temperature bore and 600 mm of height was used for magnetic separator.

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Dry separation of PVC film from waste plastic film mixture using Air Table

  • Song, Young-Jun;Hiroki Yotsumoto;Eisetsu Oi
    • Proceedings of the IEEK Conference
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    • 2001.10a
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    • pp.734-737
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    • 2001
  • A study was conducted in order to remove PVC from the waste plastic film mixture. The fittings of Air Table was modified to increase the separation efficiency of PVC. By using the improved air table, the PE and PVC was successfully separated from PVC-PE film mixture with the yield of PE 90% or more and with the content of PVC in PE 1% or less. The detail of the separation condition and result will be discussed in this paper.

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