• Title/Summary/Keyword: 정면통과

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Interaction of Encountering Two Ships with Varying Speed in Calm Water (정면으로 마주치는 선박의 선속에 따른 상호 간섭력에 관한 연구)

  • Lee, Sang-Do;Kim, Dae-Hae;Kong, Gil-Young
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2015.07a
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    • pp.11-12
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    • 2015
  • 두 선박이 정면에서 마주치며 선박간 상호 통항하거나 상대선을 추월할 경우 각 선박의 선체형상과 선속에 의한 유체력 상호작용에 따른 선박간 간섭력이 발생한다. 선박간 간섭력의 주요한 평가 요소인 횡력과 회두 모멘트의 측정을 통해 두 선박이 근접하였을 때의 위험도와 충돌을 예측할 수 있다. 선행된 간섭력에 관한 연구는 대부분 경험에 의하거나 이론적인 측면에서 관련 연구가 진행되어왔으며, 학계에서 통상적으로 널리 알려진 뉴턴의 연구(1960)에서는 깊은 수심에서 두 선박을 평행하게 항주시켰을 때 선박간 최대 흡인력은 두 선박이 정횡으로 나란하게 위치되는 지점에서 발생하고, 이때의 간섭력은 선속의 제곱에 비례한다고 추정하였다. 현대의 조선기술이 발전함에 따라 선박의 크기는 점점 대형화되고 선박의 운항 효율성 증진을 위한 다양한 선형이 개발되어 실선에 적용되고 있다. 이런 경향에 따라 과거에 비해 현대 선박 운항환경에서의 선박간 간섭은 선박의 크기 및 선형에 의한 영향이 클 것으로 판단된다. 본 연구에서는 선박의 종류별로 대표 선종을 선정하여 두 선박이 정면에서 마주치며 통과하는 운항조건에서의 선속 증가에 따른 선박 상호간 간섭력의 변화를 통상적으로 사용되는 선박조종시뮬레이터를 이용하여 실험 및 분석하여 상관관계를 도출하였다. 선박 유형에 따른 시뮬레이션 실험 결과 최대 횡력은 주로 선미 부근에서 발생하였고 최대 회두모멘트는 선수가 근접할 때 발생하였으며, 선속이 증가할수록 선박 상호간 근접거리가 좁혀졌고 선형별로 각기 다른 선속에서 선미 충돌이 발생하였다. 이 실험연구는 선형에 따른 선박 상호간 근접 시의 횡거리와 통과속력에 대한 기준 설정의 연구 근간을 마련하였고 선박간 교항시 안전운항을 위한 지침이 될 것으로 판단된다.

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Motion Visualization of a Vehicle Driver Based on Virtual Reality (가상현실 기반에서 차량 운전자 거동의 가시화)

  • Jeong, Yun-Seok;Son, Kwon;Choi, Kyung-Hyun
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.5
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    • pp.201-209
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    • 2003
  • Virtual human models are widely used to save time and expense in vehicle safety studies. A human model is an essential tool to visualize and simulate a vehicle driver in virtual environments. This research is focused on creation and application of a human model fer virtual reality. The Korean anthropometric data published are selected to determine basic human model dimensions. These data are applied to GEBOD, a human body data generation program, which computes the body segment geometry, mass properties, joints locations and mechanical properties. The human model was constituted using MADYMO based on data from GEBOD. Frontal crash and bump passing test were simulated and the driver's motion data calculated were transmitted into the virtual environment. The human model was organized into scene graphs and its motion was visualized by virtual reality techniques including OpenGL Performer. The human model can be controlled by an arm master to test driver's behavior in the virtual environment.

Development of High Efficiency Dehumidifiers in low temperature (저온에서 고효율 제습기 개발)

  • Kim, Jong-Ryeol
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.9
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    • pp.206-211
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    • 2016
  • Various applications require dry air at low temperature, such automation equipment, semiconductor manufacturing, chemical production lines, and coating processes for the shipbuilding industry. Four evaporators for low temperature (below $0^{\circ}C$) were installed for a dehumidification system. Moist air is cooled sequentially over three evaporators. The first evaporator has an evaporation temperature of $13^{\circ}C$, that of the second evaporator is $5^{\circ}C$, and that of the third evaporator is maintained at $-1.3^{\circ}C$. In the fourth evaporator implantation thereby the moisture contained in the moisture air. A pressure regulator (CPCE 12) is used at this point and is defrosted when the vapor pressure is below a set value. The non-implantation moisture of the air is a heating system that uses the waste heat of a condenser with high temperature. It develops the cooling type's dehumidifier, which is important equipment that prevents the destruction of protein and measures the temperature and humidity at each interval by changing the front air velocity from 1.0 m/s to 4.0 m/s. The cooling capacity was also calculated. The greatest cooling capacity was 1.77 kcal/h for a front air velocity of 2.0 m/s

Ultrastructural Study on the Haustorial Cells of Cuscuta australis R. Brown in the Region of the Host Parenchyma (기주식물의 유조직 속에서 생장하는 실새삼(Cuscuta australis R. Brown) 흡기세포의 미세구조)

  • 이규배
    • Journal of Plant Biology
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    • v.34 no.2
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    • pp.129-136
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    • 1991
  • Two cell types, tip cells and hyphal cells, were found at the front of Cuscuta australis endophyte growing into the stem parenchyma of the host plant, Trifolium repens. Each tip cell developed into an elongate, filamentous hypha. The cells of both types possessed a dense cytoplasm including abundant organelles and enlarged nuclei with the deeply lobed envelope. The unevenly thick walls were observed in certain tip cells. The wall penetrated through the middle lamellae of the host cells and engulfed the debris of broken host cells. Some front cells had the plasmalemma-wall invaginations, which increased the surface area and would facilitate material uptake from the host No plasmodesmata between the host and parasite cells were found; instead, an apoplastic continuity was established by fused cell walls at the interface of the two partners. The apoplast was thought to be the main route for water and nutrients transport.nsport.

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The Active Way of Trauma: Receiving the Return of the Past (도래하는 과거를 수용하는 트라우마의 능동적인 방편)

  • Seoh, Gil-Wan
    • Cross-Cultural Studies
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    • v.41
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    • pp.33-56
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    • 2015
  • Trauma studies have provided useful models for dealing with the catastrophic and disastrous events that an individual and collective group experience. Most important of all, the perspective of post-structuralist trauma study, including Cathy Caruth, became a paradigmatic model and it has been applied to almost all contexts of life. The perspective of this study model, which is called an "event-based model of trauma," focuses on the literal registration of the traumatic event and the accurate and immediate recall of the past. The person directly involved in the event becomes the passive bearer transmitting the truth of a traumatic event. From this perspective, the traumatic subject only undergoes and endures the event and cannot play an active role in constructing trauma and dealing with it. Eventually, the truth of trauma has to be obtained at the cost of the traumatic subject's autonomy and the possibility of his/her agency. The problem here is that the truth, which is reencountered through the literal return of the past, obtained at the cost of the subject's autonomy, strikes a rather fatal blow to the person, than gives help for resolving many of matters surrounding traumatic experience and curing trauma. This suggests that the active way of dealing with trauma on the part of the traumatic subject, rather than the traumatic event itself, is demanded. Furthermore, because more recently, images of disastrous events were viewed "live" by audiences and an immediacy to the event is replicated in public discourse about them, the event becomes more immediately traumatic and there is a more strong presumption that people regard themselves as traumatic victims than before. This is the reason that we must explore an active way dealing with trauma on more human position at this time. This essay aims to examine the limits of the paradigmatic model of trauma study, an "event-based model of trauma," critically through a literary, theoretical text in which it reveals how the literal return of the traumatic past have a fatal effect on the victim; and hopes to suggest "the narrative memory" as a way to deal with trauma from a more humanistic perspective.