• Title/Summary/Keyword: and hood

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Improvement of VSDS (Ventilation System Design Software) (산업환기시스템 설계 소프트웨어의 개선)

  • Park, Dong-Hee;Kim, Tae-Hyeung
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.10 no.2
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    • pp.78-97
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    • 2000
  • Designing the industrial ventilation system is the complex and time-consuming job. It could generate some errors in the design calculations if one uses the hand-calculator or the spreadsheet program. To overcome these difficulties, VSDS(Ventilation System Design Software) had been developed a few years ago. But, it had the difficulty in designing a complex system having many branches because the user can not see the layout of the system on the screen. Another difficulty is that VSDS had been based on the assumption of the standard air condition. VSDS has thus been improved to overcome the shortcomings of the old version of VSDS.

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A Study on the Flow Characteristic of Non-Thermal Plasma Reactor for Demonstration (실증실험용 저온 플라즈마 반응기의 유동특성에 관한 연구)

  • Kim, Y.S.;Choi, S.H.;Kim, J.I.;Kim, T.H.;Yoo, J.S.;Paek, M.S.;Jang, G.H.
    • Proceedings of the KSME Conference
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    • 2000.11b
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    • pp.508-513
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    • 2000
  • HANJUNG has developed demonstration plant treating combustion flue gas such as dioxide($SO_2$) and nitrogen oxides(NOx). Before operating this system, we tested the inner airflow characteristic of demonstration plant in the front of plasma reactor field 1 and field 2. The experimental results of $25,000Nm^3/hr$ airflow are compared with the computational results using FLUENT code. It is found that the velocity distribution trends are matched the experimental results with the calculation results. To improve the eccentric airflow in the inlet hood, it is necessary to install the vertical guide vane as well as the horizontal guide vane.

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Development of a new test facility for the study of pressure transients in tunnel and micro-pressure waves radiated from the tunnel exit on the railroad (철도터널내 압력변동 및 터널 미기압파 저감 시험장치개발에 관한 연구)

  • Kim, Dong-Hyeon;Oh, Il-Geun
    • Proceedings of the KSME Conference
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    • 2000.04b
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    • pp.611-618
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    • 2000
  • The test facility of the 1/60-scale models for the train-tunnel interactions was recently developed to investigate the effects of entry portal shapes, hood shapes and air-shafts for reducing the micro-pressure waves radiating to the surroundings of the tunnel exits by KRRI in Korea. The launching system of train model was chosen as air-gun type. In present test rig, after train model is launched, the blast wave by the driver did not enter to inside of the tunnel model. The train model is guided on the one-wire system from air-gun driver to the brake parts of test facility end. Some cases of the experiments were compared with numerical simulations to prove the test facility.

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Numerical Analysis on the Improvement of Zinc Plating Booth Ventilation System (아연도금 부스 환기시스템 개선에 관한 수치해석)

  • Chin, Do-Hun
    • Journal of the Korean Society of Industry Convergence
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    • v.24 no.1
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    • pp.45-51
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    • 2021
  • The purpose of this study is to suggest the optimal shape for a local air ventilation system for fume removal, which is operated in a zinc galvanizing factory, and to propose the improvement plan for a ventilation system used in a zinc galvanizing factory through flow analysis. A part of the air sprayed by an air curtain goes out. It will be necessary to research the position of an air curtain, its spray angles, and its nozzle shape. In addition, additional research needs to be conducted on the shape of the fan installed before a hood in order to make it easy to induce fume. In a local air ventilation system, air is inhaled from the outside. The higher an inlet negative pressure is, the easier fume is removed. It was found that it was necessary to install an appropriate hole in the wall on the back of a push nozzle in order to reduce an inlet negative pressure.

STUDIES OF THE MARTIAN NORTH POLAR CAP BEFORE VERNAL EQUINOX, 1975

  • IWASAKI KYOSUKE;AKABANE TOKUHIDE;TOMITA YOSHIO
    • Journal of The Korean Astronomical Society
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    • v.29 no.spc1
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    • pp.357-358
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    • 1996
  • Reanalysis of the observations of Mars made at the Hida Observatory in 1975 with a new image processing method is reported. Red filter images taken in the period before vernal equinox (areocentric longitude of the sun Ls=$0^{\circ}$) revealed dark surface features at the northern high latitudes, while blue filter images taken at the same time showed the extensive polar hood. The latitude of the northernmost feature observed was about $67^{\circ}$N. An extensive north polar cap, which is predicted by most of the existing models and observed with Viking, did not exist in our reanalyzed images obtained at the Hida Observatory in 1975.

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A Numerical Optimization Study on the Ventilation Flows in a Workshop (작업장 환기장치 최적화 유동 연구)

  • 엄태인;장동순
    • Journal of the Korean Society of Safety
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    • v.10 no.1
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    • pp.64-73
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    • 1995
  • A preliminary study is performed in order to design an effective ventilation equipment for the control of possible pollutants in a workshop. To this end, the Patankar's SIMPLE methodology is used to investigate the flow characteristics of the contaminated thermal deflected jet which is encounted often in practical hood system. SIMPLE-Consistent algorithm is employed for the pressure-velocity coupling appeared in momentum equations. A two equation, k-$\varepsilon$ model is used for Reynolds stresses. The prediction data is compared well against the experimental results by Chang(1989). Considering the control of the wake due to its high turbulence together with the stagnant feature has been investigated in term of major parameters such as temperature and magnitude of the discharge velocity. Detailed discussions are made to reduce the size of the wake region which give rise to pollutant concentration stratification.

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Experimental Study of the Non-Uniform Mean Flow at the Front of a Radiator in Engine Room (엔진룸내 방열기 전단면 유동 불균일도 측정에 관한 연구)

  • 류명석
    • Transactions of the Korean Society of Automotive Engineers
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    • v.4 no.4
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    • pp.72-79
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    • 1996
  • The recent trend of higher output engines with more auxiliary parts is resulting in greater heat generation in the engine compartment. In order to maximize the heat dissipation and eliminate the inefficient flow in the engine compartment, it is necessary to understand the flow field under the hood. In this respect, experimental study as well as numerical analysis should be conducted. The automated measuring system was constructed to obtain three dimensional mean flow data with high accuracy. The measurements have been made on a vehicle with a steady incoming air flow. The result shows that there exists a high degree of non-uniformity in the mean flow velocity at the front of radiator.

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Numerical Analysis of Flow Distribution in Dust Collector of Industrial Plant (산업용 집진기 내부 유동분포에 관한 수치해석)

  • Chin, Do-Hun
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.18 no.9
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    • pp.88-93
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    • 2019
  • The purpose of this study is to analyze the flow of a system that collects fumes in the plasma cutting machine widely used in industrial sites. A plan for improving the fume collection facility of an industrial plant using a large plasma cutter was investigated through flow analysis. Results show that it is effective to capture and suck fumes from a nearby cutter. If more hoods were installed near the cutter, fumes that were scattered internally could be removed effectively. In addition, if suction inflow was increased, the fumes could be removed more effectively.

'Youho', A New Forage Barley Cultivar with Ruminant-Palatable Hood Spike Type and Non-Scatteredness (가축 기호성이 높은 내탈립 삼차망 청보리 신품종 '유호')

  • Park, Tae-Il;Seo, Jae-Hwan;Han, Ouk-Kyu;Kim, Kyeong-Hun;Park, Ki-Hun;Oh, Young-Jin;Choi, Jae-Seong;Park, Jong-Chul;Park, Hyoung-Ho;Kim, Hong-Sik;Kim, Jung-Gon;Song, Tae-Hwa;Kim, Won-Ho;Park, Nam-Geon;Jeung, Jae-Hyun;Ju, Jung-Il;Kim, Soo-Yong;Kim, Dae-Ho
    • Korean Journal of Breeding Science
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    • v.43 no.3
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    • pp.190-195
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    • 2011
  • 'Youho' (Hordeum vulgare L.), a new ruminant-palatable forage barley cultivar, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute of Crop Science, RDA in 2008. It was derived from the cross between 'Suwon339' and 'Suwon355'. Among the cross made in 1999, a promising line, SB992047-B-B-B-6-2, showed good characteristics in potential forage yield in the yield trial tested at Iksan from 2005 to 2006. In 2007, it was designated as 'Iksan431' and placed in regional yield trials at eight locations in Korea for two years from 2007 to 2008, and was released as the name of 'Youho'. It has the growth habit of group II, erect plant type, green leaf and hood spike. Its average heading and maturing dates were on Apr. 24 and May 26, respectively, which are similar to check cultivar 'Yuyeon'. 'Youho' also showed weaker winter hardiness, but better resistance to lodging, shattering and BaYMV than those of check cultivar. It showed higher crude protein content, grade of silage quality than those of check cultivar. The average forage dry matter yield in the regional yield trial was about 14.1, $10.9MT\;ha^{-1}$ in upland and paddy field, respectively, which were 1% to 4% lower than that of the check cultivar. This cultivar would be suitable for the area whose daily minimum temperature was above $-8^{\circ}C$ in January in Korean peninsula.

The Moderating Effects on Strength and Opportunity Factors Between Entrepreneurship of Franchisor's CEO and Performance in Hood Service Franchise (외식 프랜차이즈 가맹본부 CEO의 기업가정신과 성과 간에 강점과 기회요인의 매개효과 분석)

  • Lee, Sang Suk
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.13 no.1
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    • pp.131-143
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    • 2018
  • This paper aims to investigate the moderating effects of strength and opportunity factors between entrepreneurship of food service franchisor's CEO and performance in hood service franchise. For analyzing the relationship of them, the entrepreneurship factors categorized with organizational risk taking, innovativeness, and proactiveness from previous researches(Khandwalla, 1977; Miller, 1983; Miller, 1983). Also, strength and opportunity factors classified into detailed subfactor by confirmatory factor analysis. As a result, we found some statistically significant effects between the strength and opportunity factors and entrepreneurship factors, and they sequentially affects to performance. This result means that strength and opportunity factors have a role as a moderating variables. That is, as a presented with previous research, there is verified that entrepreneurship is caused by organizational risk taking, innovativeness, and proactiveness. Also, strength and opportunity factors significantly affect to business performance. Some guidelines for practicing potential food service franchise as a result of this would include; first of all, it is important to support the potential food service franchise consulting approach for some competitive advantage; secondly, effective governmental support programs for food service franchise should be developed for positive impacts of according to these results.