• Title/Summary/Keyword: 선두부

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화합물 반도체 및 진공기술의 동반자 (주)한백

  • 허윤성
    • Proceedings of the Korean Vacuum Society Conference
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    • 2000.02a
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    • pp.32-32
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    • 2000
  • 본 발표에서는 (주)한백을 소개하고자 한다. 회사의 연혁 및 생산 품목, 부설연구소를 간략히 소개할 예정이다. (주)한백은 반도체 제조장비 및 진공시스템 개발에 있어 타사와 구별되는 창의성을 부여 해당 분야의 첨단기술 개발에 이어 독자적 기술영역을 확보해 나감으로써, 반도체 공정기술의 선두 기업으로서의 기술 개발에 전 가족들의 정렬과 노력을 아끼지 않고 있다. MOCVD 시스템을 비롯한 장비의 상용화를 실현하고 있으며 각종 과제 수행과 산학연 컨소시엄을 통한 공동연구에도 적극 참여하고 있다.

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The Numerical Analysis of Asymmetric Vortices around the Slender body at High Angle of Attack Supersonic Flow (고받음각 초음속 유동에서의 세장형 몸체 주변에 발생하는 비대칭와류에 대한 수치적 연구)

  • Jeon, Young-Jin;Ji, Young-Moo;Kim, Ki-Su;Seo, Hyung-Seok;Byun, Yung-Hwan;Lee, Jae-Woo
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2007.04a
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    • pp.335-338
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    • 2007
  • In the case of an antiaircraft missile, high angle of attack flight capability is required to get the agile maneuverability in a supersonic flow. Even through a symmetric slender body does not have side slip, asymmetric vortex is generated at high angle of attack conditions. This asymmetric vortex produces unnecessary side force and yawing moment; hence, these effects deteriorate directional stability. In this study, the numerical analysis of asymmetric vortices around the slender body was conducted at high angle of attack supersonic flow. In order to simulate the vortices, a bump is installed on the nose of the slender body. As a result of the numerical analysis, the asymmetric vortices around the slender body could be simulated.

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The Development of Model Aerodynamic Facility of Konkuk university for Real Flight Condition and High Altitude Simulation. (고고도/실기체 환경 모사를 위한 건국대 초음속 풍동 가열 시스템 성능 개선)

  • Yang, Sungmo;Kim, Young Ju;Choi, Won Kyu;Park, Soo Hyung;Byun, Yung Hwan
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2017.05a
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    • pp.647-650
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    • 2017
  • As the necessity of development of supersonic vehicle increases, securing an aerodynamic data from low to high altitude is requested for flying vehicles crusing in various high-tech environment. Therefore our research team built equipment by improving heating device of Model Aerodynamic Facility(MAF) of Konkuk University to simualte a real gas environment. Guided weapon system and temperature and velocity distribution according to the flow that is produced from the pier of supersonic vehicle is planned to be researched by using this equipment.

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Development of Cut-in Lane Changing Model Based on Observed Driver's Behavior in Uninterrupted Traffic Flow (연속교통류에서의 끼어들기 행태 분석 및 모형 개발)

  • Kim, Kyung-Hee;Chang, Myung-Soon;Kim, Jin-Tae;Kim, Eung-Cheol
    • Journal of Korean Society of Transportation
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    • v.22 no.6
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    • pp.145-157
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    • 2004
  • Microscopic freeway simulation models project the uncertain values of performance measures for subject traffic conditions by explaining drivers' driving behavior with lane changing and car-following models. However, the existing lane changing models are limited to gap acceptance oriented passive behavior of drivers and not able to capture more-or-less aggressive driving behavior(e.g. cut-in lane changing) ordinarily obseved in field. This paper suggests the definition of cut-inlane changing and presents its characteristics based on the findings from two different freeway on- and off-ramp sections. In addition, this paper proposes a new lane changing model capable of handling both passive and active drivers' driving behavior for better performance of simulations. The proposed lane changing model was tested with Hanyang Simulatin (HYTSIM), a microscopic freeway simulation program developed for this study. The HYTSIM simulation results reflecting the performance of the proposed lane changing model were compared against the field data. The test results showed that the distribution of gaps collected when vehicles change lanes were statistically identical to the field data at 95% confidence level.

A Numerical Study on the Pressure Relief in a Tunnel Using a Pressure Relief Duct (공기 압력 제어 덕트를 이용한 철도 터널 내 공기 압력 저감에 대한 수치해석 연구)

  • Seo, Sang Yeon;Ha, Heesang;Lee, Sangpil
    • Tunnel and Underground Space
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    • v.26 no.5
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    • pp.375-383
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    • 2016
  • High-speed trains have been developed widely in many countries in order to transport a large quantity of people and commodities rapidly. When a high speed train enters a tunnel, aerodynamic resistance is generated suddenly. This resistance causes micro pressure wave and discomfort to passengers. Therefore, it is essential to incorporate a pressure relief system in a tunnel and streamlined shape of a train in order to reduce aerodynamic resistance caused by a high-speed train. Additionally, the cross-sectional area of a tunnel should be carefully determined to reduce discomfort of passengers. A pressure relief duct and a vertical shaft are representative measures in a tunnel. This study represents the effect of pressure relief ducts in order to alleviate pressure changes within a time period in a tunnel. One-dimensional network numerical simulations were carried out in order to estimate the effect of pressure relief systems.

Flow Characteristics and Drag Reduction at Different Pressures of Counterflow Air Jets in Supersonic Flow (초음속 환경에서 역분사 공기 제트의 압력 변화에 따른 유동 특성 및 항력 감소)

  • Choi, Jongin;Lee, Jaecheong;Kang, Seungwon;Huh, Hwanil
    • Journal of the Korean Society of Propulsion Engineers
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    • v.22 no.1
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    • pp.58-65
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    • 2018
  • To improve the performance of high-speed vehicles, various studies have been carried out on the head of vehicles. In this study, tests are conducted on flow characteristics and drag reduction using counterflow air jets in supersonic flow. The flow is visualized by the Schlieren method using a high-speed camera, and the drag is measured using a torque sensor according to the injection pressure conditions. The results of the measurements indicate that the flow changes from unsteady state to steady state for injection pressure ratios between 1.58 and 1.70, and drag reduction is observed as the pressure of the counterflow air jets increases.

Health Promotion in Canada (캐나다의 건강증진)

  • George, Anne
    • Proceedings of The Korean Society of Health Promotion Conference
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    • 2001.09a
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    • pp.81-89
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    • 2001
  • Canada has a rich history in the theory and development of the field of health promotion. Over 25 years ago, in 1974, the Canadian government produced the first government policy document that identified health promotion as a national strategy. The document, which came from the national Health Minister, was entitled A New Perspective on the Health of Canadians (Lalonde, 1974).

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A Study on the Responsibility for a Barge's Safety Management in a Marine Construction (해상공사에 투입된 부선의 안전관리 책임에 대한 연구)

  • Jang, Yeong-Jun
    • Journal of Navigation and Port Research
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    • v.39 no.1
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    • pp.37-43
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    • 2015
  • At marine construction sites, there are problems with regard to dispute on the responsibility of safety management of chartered barge and its legal issues. In general, demise charter with crew is used for barge charterparty which is committed to the marine construction. Although Chapter 5 of the Korean Commercial Act enact provisions regulating a Time Chargerparty and a Bareboat Charterparty, it is difficult to clarify where the responsibility lies with regard to the safety control of the chartered barge. For this reason, disputes on accountability arise when accident occurs in effect. As a result, parties of the charterparty shift the responsibility on each other and there is increased risk for occurrence of similar accidents. There is no legally required qualification for a head of barge workers who is in charge of barge management. It is not possible to demand the head of barge workers to take charge of tasks which requires professional judgment as a marine technician considering his daily work scope. Furthermore, the barge committed to the marine construction as a form of bareboat charter or equipment charterage is an object which should be managed by safety supervisor of the charterer's marine construction. The charterer bears a duty to manage the safety of the barge. Therefore, the charterer is generally liable for the damage incurred in the course of using the chartered barge.

A Numerical Study on the Effect of Pressure Relief Ducts on the Normal Pressure in a Preliminary Design of Honam-Jeju Subsea Tunnel (호남-제주 해저터널 가상설계의 공기압력 제어 덕트가 열차 주행에 미치는 영향에 대한 수치해석 연구)

  • Seo, Sangyeon;Ha, Heesang
    • Journal of the Korean GEO-environmental Society
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    • v.17 no.8
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    • pp.17-27
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    • 2016
  • High-speed trains have been developed widely in European countries and Japan in order to transport large quantity of people and commodities in short time. Additionally, a high speed train is one of the most desirable and environmentally friendly transportation methods. When a high speed train enters a tunnel, aerodynamic resistance is generated suddenly. This resistance causes micro pressure wave and discomfort to passengers. Due to this aerodynamic pressure against the train, a large amount of traction is required for the operation of a train in a tunnel. Therefore, it is essential to incorporate a pressure relief system in a tunnel in order to reduce aerodynamic resistance caused by a high-speed train. A pressure relief duct and a vertical shaft are representative measures in a tunnel. This study represents the effect of pressure relief ducts in order to alleviate positive and negative normal pressures acting on a train. One-dimensional numerical simulations were carried out in order to estimate the effect of pressure relief systems.

An Experiment on Walking Speeds of Freshmen Unexperienced in Shipboard Life on a Passenger Ship (승선생활 미숙련 대학 신입생들의 여객선 내 보행속도 실험)

  • Hwang, Kwang-II
    • Journal of Navigation and Port Research
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    • v.37 no.3
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    • pp.239-244
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    • 2013
  • To increase the safety of onboard evacuation of guests who is unfamiliar with onboard living conditions, this study measured and compared the onboard walking speeds of 81 participants on a passenger ship, I t were found that the walking speeds at corridor on navigation were slower than those at berth by 27.2%, and the speeds of walking on the corner on navigation were slower than those at berth by 23.2%. This means that the ship motion on navigation directly influenced walking speeds. The walking speeds of upward-stairs and downward-stairs were measured to be 0.71m/s and 0.75m/s, respectively. From the crowd counter-flow experiments, because of the narrow space between participants, the walking speeds were decreased as person after person. And it was clear that the group's walking speeds were determined by the walking speeds of leading person(s) of the group. The walking speeds obtained this study were different from those of IMO guideline(MSC/Circ 1033).