• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.2 no.11
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• pp.49-54
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• 1981

벼 통일계 신품종이 지난 1971년부터 우리나라에 재배돼면서부터 이들 신품종은 녹색혁명의 총아로 각광을 받게됐으며 더욱이 이들 신품종은 도열병에 대한 내병성이 강한것으로 알려져 증산의 꿈은 조기에 실현될듯 했다. 그러나 1976년 전북진안에서 1977년에는 임실에서 도열병변이균이 발견되더니 급기야 1978년에는 전국적으로 만연, 통일계품종이 이병화 품종으로 전락됐다. 올해는 전북 운봉에서 황숙기에 목도열병이 발생, 일부 지방 및 중앙지에 새로운 도열병이 발생됐음을 보도했다. 그러나 현지 농촌진흥원의 조사결과로는 새로운 변이균이 아니고 재래균으로 판명되고 있어 일단 안심은 돼나 이 지역이 위치$\cdot$기후적으로 새로운 도열병변이균이 발생될 가능성이 많은 지역이라 올해에 문제됐던 운봉지역 목도열병의 발생실태와 대책을 2회에 걸쳐 알아본다.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.520-525
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• 2000

This research is to analyze the ventilation performance of mechanical ventilation systems for indoor air quality control and management. A ventilation performance with supply sites is evaluated in a test model chamber and office room. A $CO_2$ gas as a tracer gas is used to measure the ventilation performance. The ventilation performance is found to increase with increased the ventilation rate. The ventilation performance is analysed with 55% at the supply air of 570 lpm and with 20% at the supply air of 100 lpm in a test chamber. The ventilation performance is better than 15% comparing with natural decay at the supply of 570 lpm in office room.

• The Science & Technology
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• v.9 no.7 s.86
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• pp.20-22
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• 1976

고래로부터 인간이 고안한 기술은 수렵, 가축, 농업 등에서 출발해서 기기나 동력을 더 많이 사용하는 형태로 발전해왔다. 그리고 급기야는 자동제어 등에 이르러 인간을 필요로 하지 않는 방향으로 유도되고 있다. 이러한 비인간적인 지향성을 가진 기술의 진보가 초래한것 중에는 인간과 그 사회에 구 많은 마이너스도 있었다. 이러한 기술의 발달을 보다 인간의 이익으로 유도하기 위해 기술평가의 개념이 진보하게 되었다. 이러한 발전으로 식품공업도 많이 변모하였고 식생활의 변화를 필연적으로 가지고 왔다. 식생활과 보건관리는 직접 사람에 직결되는 사항이다. 따라서 다른 여러 기술에 비해 일반국빈의 관심이 높고 정부가 직접 개입하게도 된다. 이러한 기본적인 생각은 식품이나 의약에만 필요한것이 아님은 오늘날의 생활환경을 생각해 보면 자명해 진다. 어떠한 기술도 기본적인 인권이라고 할 수 있는 건강이라든가 생할환경 등의 기본적인 요구를 저해해서는 안 되는 것이다. .

• Fire Science and Engineering
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• v.30 no.5
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• pp.74-81
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• 2016

This study evaluated the habitability of operators for main control room fires in nuclear power plants. Fire modeling (FDS v.6.0) was utilized for a fire safety assessment so that it could determine the performance of the smoke ventilation and operator habitability with the main control room. For this study, it categorized fire scenarios into three cases depending on the conditions in the HVAC system. As a result of fire modelling, it showed that Case 1 (with HVAC) would give rise to the worst situation associated with the absolute temperature, radiative heat flux, optical density, and smoke layer height as deliberating the habitability and smoke ventilation. On the other hand, it showed that Cases 2 (w/o HVAC) and 3 can maintain much safer situations than Case 1. In the case of temperature at 820 s, Cases 2 and 3 were up to approximately 63% greater than Case 1 in the wake of ignition. In addition, the influence of radiative heat flux of Case 1 was even larger than Cases 2 and 3. That is, the radiative heat fluxes of Cases 2 and 3 were approximately 68% higher than Case 1. Furthermore, when it comes to considering the optical density, Case 1 was approximately 93% greater than Cases 2 and 3. Accordingly, it expected that the HVAC system can influence a the performance on the smoke ventilation that can be sustainable for operator habitability. On the other hand, it revealed an inconsecutive pattern for the smoke layer height of Cases 2 and 3 because supply vents and exhaust vents were installed within the same surface.

• Journal of the Korean Society for Railway
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• v.17 no.5
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• pp.328-335
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• 2014

Numerical prediction methods were applied to investigate the turbulent air currents and air-conditioning efficiency in an underground subway station, and the results compared to experimental data. The Shin-gumho Station($8^{th}$ floor underground and 43.6m in depth) in Seoul was selected for the analysis. The entire station was covered for simulation and the ventilation mode was ordinary. The ventilation diffusers were modeled as 95 square shapes of $0.6m{\times}0.6m$ in the lobby and as 222 square shapes in the platform. Cooling air of $47,316m^3/h$ was supplied and the returned air of $33,980m^3/h$ is exhausted in the lobby and the cooling air of $33,968m^3/h$ is supplied and the returned air of $76,190m^3/h$ was exhausted in the platform which is the same as the experimental data. The cases of the screen-door-closed and open were respectively investigated. A total of 7.5million grids were generated and the whole domain divided into 22 blocks for MPI efficiency of calculation. Large eddy simulation (LES) was applied to solve the momentum and energy equation.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.3
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• pp.363-375
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• 2019

Since the double-deck tunnel is deeply constructed in the city, it is necessary to secure the installation space of air supply and exhaust, escape passage stairs, elevator, distribution facilities and connection tunnels in the vertical shaft for the double-deck tunnel. Also, in order to minimize the effect of construction on adjacent area, it is necessary to construct the concrete structures at high speed in vertical shaft after tunnel excavation. Therefore, the slabs and the stairs in vertical shaft are needed to be constructed using precast concrete, and the rapid construction techniques of bracket for supporting the inner precast structure are needed. The bracket installation methods include cast-in-place concrete, precast concrete and steel. In this study, the improvement of the steel brackets with good economical efficiency and good workability was carried out in consideration of the improvement of the construction speed. We have developed a new bracket that is optimized through bracket shape improvement, anchor bolt position adjustment and quantity optimization. As a result of the structural performance test, it was confirmed that the required load supporting capacity was secured. As a result of structural performance test for bar type anchor bolt and bent anchor anchor bolt, it was confirmed that the required load carrying capacity was secured and that the load bearing capacity of bent anchor bolt was large.

• Journal of Korean Medical classics
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• v.18 no.3 s.30
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• pp.95-105
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• 2005

통과대설기적외과의적급기내용적연구(通過對薛己的外科醫籍及其內容的硏究), 득출이하결론(得出以下結論): 1. 설기소저외과의적중최조편찬적시(薛己所著外科醫籍中最早編纂的時)${\lceil}$외과심법(外科心法)${\lrcorner}$(1528년(年)), 지후편찬적차서시(之後編纂的次序是)${\ulcorner}$외과발휘(外科發揮)${\lrcorner}$(1528년(年)), ${\ulcorner}$외과경험방(外科經驗方)${\lrcorner}$(1528년(年)), ${\ulcorner}$외과추요(外科樞要)${\lrcorner}$(1545년(年)), ${\ulcorner}$여양기요${\lrcorner}$(1554년(年)). 2. 설기개변이왕양의수증처방적악습(薛己改變以往瘍醫隨症處方的惡習), 파변증론치인용도료외과임상상(把辨證論治引用到了外科臨床上). 3. 재망진방면불근중시료국부적진찰(在望診方面不僅重視了局部的診察), 이차중시관찰전신적상태(而且重視觀察全身的狀態); 환중시료사진합참(還重視了四診合參), 우기중시료망진화절진(尤其重視了望診和切診). 4. 재치료방면령활지운용료소통(在治療方面靈活地運用了疏通), 발산(發散). 화해(和解), 보탁(補托), 온보등방법(溫補等方法), 이차환사용료침(而且還使用了針), 폄, 구(灸), 위등외치법(慰等外治法). 5. 설기소저적(薛己所著的)${\ulcorner}$여양기요${\lrcorner}$시일부조기간행적미풍병전저(是一部早期刊行的麻風病專著).

• Journal of the Society of Naval Architects of Korea
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• v.30 no.2
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• pp.123-131
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• 1993

Since the years of oil tanker production in the 70's, the concern of marine enviromental protection is worldwidely increased, at last it is compulsorily ruled to product the double hull tanker by International Maritime Organization(IMO). Throughout these informative years Daewoo Shipyard has developed the double hull VLCC for a future vessel. The paper presents hull design for 300K double hull VLCC which was carried out to satisfy with statutory requirement of it, focused the structural arrangement and direct calculation in cargo hold area.

• Journal of the Korean Institute of Gas
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• v.28 no.1
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• pp.11-18
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• 2024

If flammable liquid leaks, vapor evaporated from the pool can cause poisoning or suffocation to workers, leading to secondary accidents such as fires and explosions. To prevent such damage, ventilation facilities shall be installed when designing indoor workplaces. At this time, the behavior varies depending on the characteristics of the leaked chemical, so it is necessary to select a suitable vent location according to the material. Therefore, 3D CFD simulations were introduced to derive optimal vent position and ventilation efficiency was quantitatively evaluated by vent position. At this time, assuming a situation in which flammable liquids leak at indoor workplaces to form pools, the concentration of vapor evaporated from pools was compared to derive the optimal vent position. As a result of research on toluene with high vapor density, ventilation efficiency was confirmed to be the highest at the upper supply-lower exhaust, and it is judged that introducing it can achieve about 3.7 times ventilation effect at the same maintenance cost. Through this study, it is expected that the workplace will be able to secure workers' safety by applying simulation results and installing ventilation ports.

• Land and Housing Review
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• v.3 no.1
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• pp.89-96
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• 2012

The purpose of this study was to evaluate the applicability of hybrid ventilation system in apartment housings and present a design method to improve the performance of hybrid ventilation system using the CFD simulation. As the object of CFD simulation, a small apartment houses with area of $51m^2$ and $81m^2$ were selected and evaluated. The test hybrid ventilation system are window frame natural air supply & duct exhaust hybrid system(Hybrid 1) and window frame natural air supply & bathroom and livingroom exhaust hybrid ventilation system(Hybrid 2). To evaluate the ventilation efficiency, we used the locations of diffuser installed for each system as the variables through the CFD simulation. In the case of Hybrid 1, the ventilation efficiency of the exhaust duct diffuser located on the inside room was higher rather than the exhaust duct diffuser located on the entrance. In the case of Hybrid 2, the most efficient system was the system that the diffuser connecting the bathroom static pressure fan is installed on the center of the living room. The ventilation efficiency of the Hybrid 2 in the case of $51m^2$ type was more than 20% of the Hybrid 1. But, The ventilation efficiency of the Hybrid 2 in the case of $84m^2$ type was more than 14% of the Hybrid 1. Therefore, to apply the Hybrid ventilation, a study that considers various variable should be conducted.