• 한국산업보건학회지
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• 제10권2호
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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.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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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.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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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.

• 한국산업융합학회 논문집
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• 제24권1호
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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.

• 천문학회지
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• 제29권spc1호
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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.

• 한국안전학회지
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• 제10권1호
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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.

• 한국자동차공학회논문집
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• 제4권4호
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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.

• 한국기계가공학회지
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• 제18권9호
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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.

• 한국육종학회지
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• 제43권3호
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• pp.190-195
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• 2011

청보리 신품종 '유호'는 까락이 없어 가축 기호성이 높지만 수확 시 곡실의 탈립이 많아 수량 및 영양적 손실이 큰 기존 삼차망 품종 '유연'의 단점을 개선하기 위하여 1999년에 내탈립 삼차망인 수원339호를 모본으로 하고, 보리호위축병에 강하고 총체적성에 좋은 수원355호를 부본으로 교잡하여 계통육종법에 의하여 제반 특성이 우수한 'SB992047-B-B-B-6-2' 계통을 선발, 생산력검정시험과 지역적응시험을 거쳐 2008년에 육성되었다. 그 특성을 요약하면 다음과 같다. 1. '유호'는 직립 초형으로 파성이 II 정도이며, 잎은 녹색이면서 넓고, 줄기 굵기는 중간 정도이며, 이삭은 길고 까락은 삼차망이다. 2. '유호'의 초장은 106 cm로 대비품종인 '유연'에 비해 장간형이었고, $m^2$당 분얼수는 684개로 '유연'보다 36개 많은 다얼성이었으며, 평균 출수기와 성숙기는 각각 4월 24일과 5월 26일로 '유연'과 비슷하였다. 3. '유호'는 '유연'보다 추위에 약하였으나 도복에 강하였고, 호위축병은 익산(III형), 나주(I형), 진주(IV형) 등 모든 지역에서 저항성을 보였다. 4. '유호'의 건물수량은 전작에서 14.1 ton/ha, 답리작에서 10.9 ton/ha으로 '유연'보다 3~4% 정도 낮았다. 5. '유호'는 '유연'에 비해 황숙기에 곡실의 탈립 정도가 매우 낮았고, 조사료 품질은 조단백질 함량 9.3%, ADF 25.0%, TDN 69.2%로 '유연'과 대등하였으며, 젖산 함량은 14.5%로 13.1%인 '유연'에 비해 높았고, 사일리지 등급은 II 등급으로 양호하였다.

• 벤처창업연구
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• 제13권1호
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• pp.131-143
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• 2018

본 연구는 외식 프랜차이즈의 기업가정신이 경쟁(강점) 및 대응(기회)능력에 영향을 미치며 또한 성과에 유의한 영향을 줄 수 있음을 검증하였다. 이러한 연구의 목적을 달성하기 위하여 기업가정신은 기존연구자들(Khandwalla, 1977; Miller, 1983)에 의해서 주장해 왔던 위험감수성, 진취성, 혁신성의 차원을 포함하는 변수들을 이용하였으며, 경쟁 및 대응능력, 성과 간의 관계분석을 위하여 구조방정식모형을 이용하였다. 본 연구의 가설 검정 결과는 다음과 같이 요약될 수 있다. 첫째, 가설(HI)은 외식 프랜차이즈의 기업가정신(진취성, 위험감수성, 혁신성)이 경쟁(강점) 및 대응(기회)능력에 정(+)의 영향을 미치는 것으로 나타났다. 즉, 외식 프랜차이즈의 기업가정신이 강할수록 더 높은 경쟁(강점) 및 대응(기회)능력을 기대할 수 있다고 볼 수 있다. 특히 기업가정신의 구성요소 중에서 혁신성은 다른 요인에 비해서 큰 영향을 미치고 있는 것으로 분석되었다. 둘째, 가설(HII)은 경쟁(강점) 및 대응(기회)능력은 성과에 정(+)과 부(-)의 영향을 미치는 것으로 나타났다. 즉, 강점과 기회요인은 긍정적인 영향을 미치는 것으로 나타났다. 본 연구 결과, 외식 프랜차이즈 강점 및 기회요인의 경쟁(대응)능력을 어떻게 적극적으로 대처하는 정도에 따라 성과에 영향을 미치는 것으로 확인되었다. 이러한 결과의 실천은 강점과 기화요인의 적극적인 개발을 통해서 이루어질 수 있으며, 정부의 프랜차이즈 환경 및 제도(정책)의 개선은 바람직한 방향으로 외식 프랜차이즈가 성장할 수 있을 것으로 판단된다.