• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.4
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• pp.123-131
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• 2006

The majority of pedestrian fatalities and injuries are caused by vehicle-pedestrian accidents. Recently, it has been recognized as a serious problem. Injuries of occupants in a vehicle have been decreased considerably. However, efforts for protection of pedestrians are still insufficient. These days, many advanced industries are striving for a better protection of pedestrians by using an active hood lift system, rather than reforming the existing structure. In this research, the active hood lift system is designed to enhance the performance for protection. The active hood lift system is analyzed by using the nonlinear finite element method. An optimization problem is formulated by incorporation of the analysis results. Orthogonal arrays are utilized to solve the formulated problem. An iterative optimization algothrithm using orthogonal arrays is utilized for design in the discrete space. It is found that the method can remarkably decrease the number of function evaluations.

• Journal of Environmental Science International
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• v.5 no.6
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• pp.683-697
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• 1996

Industrial ventilation is a crucial engineering measure to protect workers from hazardous airborne contaminants. Designing a ventilation system is not an easy task. To solve this problem, many U. S. computer programs and softwares have been developed. In Korea, asoftware, called as VPMC, was developed by Korea Industrial Safety Corporation. But VPMC could not stand alone since it can be used to design not a hood, but a ventilation system. In this research, therefore, a preprocessing software was developed. It can be used to design general ventilation system, canopy hood, open surface tank hood. The program was written in Microsoft Visual Basic. In near future, this software will be incorporated into a total package software which can be used to design a whole ventilation system.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.872-877
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• 2005

The train entry into a tunnel generates a strong compression wave in the tunnel. The high amplitude of compression wave causes high pressure gradients that are responsible for both the aural discomfort of passengers and the impulsive acoustical wave called the miro-pressure wave. This paper provides a numerical study on effects of hood for micro'-'pressure wave reduction. An axisymmetric numerical solver, considering the cross sectional area of Korean Tilting Train eXpress, is used for a transient flow field in the tunnel. Results show that the micro-pressure wave is able to be reduced by a hood. In this results, the maximum reduction of micro--pressure wave is shown at 2L(length), 1.35D(diameter) hood around $56\%$ against the non-hood case.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.1
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• pp.36-44
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• 2005

A push pull hood system is frequently applied to control contaminants evaporated from an open surface tank in recent years. Efficiency of push pull hood system is affected by various parameters, such as cross draft, vessel shapes, size of tanks surface, liquid temperature, and so on. Among these, velocity of cross draft might be one of the most influencing factor for determining the ventilation efficiency. To take account of the effect of cross draft velocities over 0.38m/s, a flow adjustment of ${\pm}$20% should be considered into the push and +20% into the pull flow system Although there are many studies about the efficiency evaluation of push pull hood system based on CFDs(Computational Fluid Dynamics) and experiments, there have been no reports regarding the influence of velocities and direction of cross-draft on push-pull hood efficiency. This study was conducted to investigate the influence of cross draft direction and velocities on the capture efficiency of the push-pull ventilation system. Smoke visualization method was used along with mock-up of push-pull hood systems to verify the ventilation efficiency by experiments. When the cross-draft blew from the same origins of the push flows, the efficiency of the system was in it's high value, but it was decreased significantly when the cross-draft came from the opposite side of push flows Moreover, the efficiency of the system dramatically decreased when the cross-draft of open surface tank was faster than 0.4m/s.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.962-969
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• 2013

This study used Computational Fluid Dynamics(CFD) to assess the properties of the air current inflow and the flow velocity distribution in the fume hood. In order to verify the effect of improvement, it was also predicted the characteristics of the flow pattern in case the hood face is structurally improved. The assessment of the capture velocity with the existing fume hood confirmed maximum 23 to 30% difference as compared to the root mean square (RMS). And the hood face showed great difference in flow velocity, with the flow velocity in the upper part is 58 to 68% faster than that in the lower part of the hood. So, as a result of the improvement of the hood designed to maintain a steady exhaust at the hood face (that is, installing a baffle on the inner wall and designing the slot type face), a difference of maximum 7% as compared to RMS appeared while maximum 12% differentiation in flow velocity through sections was predicted, showing mitigation of much of the difference in control velocity as compared to the previous structure.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.4
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• pp.238-244
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• 2008

This study investigates on the improvement of inhalation effect of hood which attached new device named as "gas-guide-device" in local exhaust ventilation system for the effective elimination of harmful material and dust in manufacturing factory. The gas-guide-device having a diamond shape is composed of width (b) and two sides of a device (X, Y) and its size is selected the industrial hood under application in manufacturing factory after due consideration. In order to investigate the effect of gas-guide-device, numerical and experimental study is performed that the flow velocity is calculated and is measured by a commercial program "COMSOL $Multiphysics^{TM}$" and a hot wire type of anemometer, respectively. The numerical and experimental results are revealed is a similar pattern and flow velocity has improved to hood attached gas-guide-device. Also, the numerical method and result is also verified the dependance. Moreover, the optimum shape and size of gas-guide-device is revealed that the width (b) and the ratio of two sides of gas-guide-device (X, Y) has 125mm and 4 to 6.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.2 no.1
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• pp.49-56
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• 1998

This study identified the fumes produced from the cooking of the seasoned meats containing various condiments such as garlic, onion, pepper, soy sauce, and sesame oil. Concentrations, at the breathing zone of the cook, of volatile organic compounds (VOCs) and aldehydes included in the cooking fumes of seasoned meats were identified. Many chloro and fluoro-aliphatic hydrocarbons, aromatic hydrocarbons, ketones, and aldehydes, which could be carcinogen suspecting chemicals, were producing from the cooking fumes of the seasoned meats. This study also identified the ventilation efficiencies of the cooking fumes of the six exhaust ventilation systems, which were widely being used in the general apartments, houses, and small-food factories. For a comparison of the ventilation efficiencies of the systems, acetaldehyde was chosen as a marker pollutant and its concentrations at the breathing zone of the cook were identified. The laboratory fume hood showed the best ventilation efficiency of the six ventilation systems studied, and then the lateral hood ventilation and the down draft ventilation followed the laboratory fume hood. Finally, this study identified that both a wall factor nearby pollutant sources and a distance factor between the hood face and pollutant sources should be also considered for an effective local exhaust ventilation system design.

• Korean Journal of Weed Science
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• v.6 no.2
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• pp.191-200
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• 1986

The study was conducted to screen paraquat-tolerant plant species among crops and weeds, using the response of plant like leaf disc discoloration, visual injury and dry weight in the presence of paraquat. Mechanism of paraquat-tolerance was investigated in strains of soybean through evaluating activities of superoxide dismutase and peroxidase and the multiplication of callus derived from soybean cotyledon. In crops, Kwanggyo has been selected as a paraquat-tolerant variety among soybean cultivars tested, and Hood as a susceptible one. In weeds, Polygonum aviculare, Chenopodium album and Pinellia ternata were evaluated as the paraquat resistant species, providing the possibility for the donor plant species for paraquat resistance. Activity of superoxide dismutase known to detoxify paraquat was markedly greater in Kwanggyo, a paraquat-tolerant cultivar than in Hood, a susceptible one. In addition, the similar response like superoxide dismutase was observed in peroxidese activity. The greater inhibition of callus multiplication was determined in Hood, a susceptible one than a tolerant one, Kwnggyo. Based on all the informations, it is strongly proposed that paraquat tolerance in soybean is due to destruction of $O_2^-$ by elevated concentration of superoxide dismutase in the tolerant cultivar.

• Journal of Environmental Science International
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• v.2 no.1
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• pp.49-56
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• 1993

This study identified the fumes produced from the cooking of the seasoned meats containing various condiments such as garlic, onion, pepper, soy sauce, and sesame oil. Concentrations, at the breathing zone of the cook, of volatile organic compounds (VOCs) and aldehydes included in the cooking fumes of seasoned meats were identified. Many chloro- and fluoro-aliphatic hydrocarbons, aromatic hydrocarbons, ketones, and aldehydes, which could be carcinogen suspecting chemicals, were producing from the cooking fumes of the seasoned meats. This study also identified the ventilation efficiencies of the cooking fumes of the six exhaust ventilation systems, which were widely being used in the general apartments, houses, and small-food factories. For a comparison of the ventilation efficiencies of the systems, acetaldehyde was chosen as a marker pollutant and its concentrations at the breathing zone of the cook were identified. The laboratory fume hood showed the best ventilation efficiency of the six ventilation systems studied, and then the lateral hood ventilation and the down draft ventilation followed the laboratory fume hood. Finally, this study identified that both a wall factor nearby pollutant sources and a distance factor between the hood face and pollutant sources should be also considered for an effective local exhaust ventilation system design.

• Journal of Power System Engineering
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• v.12 no.4
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• pp.64-71
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• 2008

This study is on pedestrian protection device using pneumatic cylinder and simple link mechanism when vehicle collide with pedestrian. This study ensured the safety space between engine and hood after it applies to simple link mechanism and pneumatic cylinder. It can absorb the damage which measure the specific device if vehicle collide with pedestrian. Combination of simple link mechanism and pneumatic cylinder was more superior than the present pedestrian protection device. Simple link mechanism could confirm superior height and survival probability than when only cylinder operated. It also ensured enough space between engine and hood. And if a cylinder is not working because of old cylinder, poor repair or damage of accident vertical cylinder would be difficult to execute because there exists the irregular space between engine and hood. If simple link mechanism operates with only one cylinder it could ensure the regular space because simple link mechanism set up at the middle of hood. So this device could confirm high safety for pedestrian.