• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.263-264
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• 2000

여과포 표면상에 도달하는 입자의 농토를 낮추거나 균일하게 유지시킬 경우, 부착된 입자층 두께의 성장으로 인한 압력손실의 증가율을 줄일 수 있고 이로 인하여 탈진 주기 또한 감소시킬 수 있다. 탈진조작의 저감으로 인하여 여과포의 수명 증대로 여과포의 교체 시기를 연장시킬 수 있으므로 여과포 집진장치의 운전 및 유지 보수비의 저감을 이룰 수 있다. 본 연구에서는 집진용기의 중간부분에 위치한 접선 유입관을 통하여 오염입자를 함유한 기체유동을 유입시킨 후, 원심력과 난류확산에 의하여 집진용기 내벽과 내통(inner tube) 벽면에 부착된 입자는 중력에 의하여 용기 바닥으로 모인 후 바닥면에 설치된 스크래퍼(scraper)를 통하여 분리 처리될 수 있는 새로운 형상의 집진장치를 개발하고자 하였다. (중략)

• Journal of the Korean Society for Precision Engineering
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• v.28 no.10
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• pp.1189-1195
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• 2011

For side airbag, the pipe type inflators have been wide used while the disk type inflators have been used for front airbag. For helping to prevent injury and death the airbag inflator system should be design with great care. The present study deal with optimizing the design of side airbag inflator by finite element analysis and design of experiment method. An optimization process was integrated to determine the optimum design variable values related to the side airbag inflator. Free shape optimization method has been carried out to find a optimal shape on an side airbag inflator model. Optimization of the air bag inflator was successfully developed using Sharpe optimization was carried out to find a new geometry. The improved results compared to the base design specification were achieved from design of experiment and optimization.

• 한국가시화정보학회:학술대회논문집
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• 2002.11a
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• pp.53-54
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• 2002

Plasma ignition method has been applied in various fields particularly to the rocket propulsion, pyrotechnics, explosives, and to the automotive air-bag system. Ignition method for those applications should be safe and also operate reliably in hostile environments such as; electromagnetic noise, drift voltage, electrostatic background and so on. In the present study, a semiconductor bridge (SCB) plasma ignition device was fabricated and its plasma characteristics including the propagation speed of the plasma, plasma size, and plasma temperature were investigated with the aid of the visualization of micro scale plasma $(i.e.,\;\leq\;350\;{\mu}m)$, which generated from a Micro-Electro-Mechanical poly-silicon semiconductor bridge (SCB).

• Proceedings of the KAIS Fall Conference
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• 2011.12a
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• pp.262-265
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• 2011

본 연구는 탈진 기류 분사 시스템의 최적화 설계에 관한 기초 연구의 일환으로 전산유체역학(CFD)을 이용하여 일반 블로우 튜브와 단순 벤츄리 조합의 충격 기류(Pulse air jet) 방식의 탈진 장치에 대한 탈진 성능과 벤츄리 입구에 기류 유도용 구조물을 설치한 경우의 탈진 성능을 비교하였다. 각 Case별로 벤츄리 내부로 유입되는 탈진 공기량을 예측한 결과, case 2의 벤츄리 형상 개조시 case 1 보다 벤츄리로 유입되는 탈진 공기량이 약 20% 증폭되는 것으로 나타났다. 또한 필터백 표면에서의 탈진 기류 전달 분포를 예측한 결과, 모든 case가 필터백의 국한된 영역으로 탈진 기류가 집중됨을 알 수 있었다. 또한, case 2의 경우가 case 1보다 오히려 탈진 기류의 전달 수준이 불량함을 알 수 있다. 이는 case 2의 경우 벤츄리 입구에 기류 유도용 구조물을 설치한 것이 탈진 공기량을 증폭시키는데에는 도움이 되나, 오히려 벤츄리 내부로 유입된 탈진 기류의 직진성을 보완하여 필터백 내부에서 탈진 기류의 확장을 방해하기 때문인 것으로 판단된다.

• International Journal of Aeronautical and Space Sciences
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• v.15 no.3
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• pp.335-343
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• 2014

An airbag is an important safety system and is well known as a safety system in cars during an accident. Airbag systems are also used as a shock absorber for UAVs to assist with rapid parachute landings. In this paper, the dynamics and gas dynamics of five airbag shapes, cylindrical, semi-cylindrical, cubic, and two truncated pyramids, were modelled and simulated under conditions of impact acceleration lower than $4m/s^2$ to avoid damage to the UAV. First, the responses of the present modelling were compared and validated against airbag test results under the same conditions. Second, for each airbag shape under the same conditions, the responses in terms of pressure, acceleration, and emerging velocity were investigated. Third, the performance of a pressure relief valve is compared with a fixed-area orifice implemented in the air bag. For each airbag shape under the same conditions, the optimum area of the fixed orifice was determined. By examining the response of pressure and acceleration of the airbag, the optimum shape of the airbag and the venting system is suggested.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.2
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• pp.126-130
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• 2012

Purpose : Methode an effective block was investigated to deal with volatile radioactive gas, short lived radioactive waste generated as a result of the routinely produced radiopharmaceuticals FDG (2-deoxy-2-[$^{18}F$]fluoro-D-glucose) and compound with $^{11}C$. Materials and Methods : All components of the radiation stack monitoring and data management system for continuous radioactive gas detection in the air extract system purchase from fixed noble gas monitor of Berthold company. TEDLAR gas sampling bags purchase from the Dongbanghitech company. TEDLAR gas sampling bags (volume: 10 L) connected via paraflex or PTFE tubing and Teflon 3 way stopcock. When installing TEDLAR gas sampling bags in Hot cell on the inside and not radioactive gas concentrations were compared. According to whether the Hot cell inside a activated carbon filter installed, compare the difference in concentration of the radioactive gas $^{18}F$. Comparison of radiation emission concentration difference of module a FASTlab and TRACElab. Results : Activated carbon filter are installed in the Hot cell, a measure of the concentration of radioactive gas was 8 $Bq/m^3$. Without activated carbone filter in the hot cell was 300 $Bq/m^3$. Tedlar bag prior to installation of the radioactive gases a measure of the concentration was 3,500 $Bq/m^3$, $^{11}C$ synthesis of the measured concentration was 27,000 $Bq/m^3$. After installed a Tedlar bag and a measure concentration of the radioactive gases was 300 $Bq/m^3$ and $^{11}C$ synthesis was 1,000$Bq/m^3$. Conclusion : $^{11}C$ radioactive gas that was ejected out of the Hot cell, with the use of a Tedlar gas sampling bag stored inside. A compound of 11C is not absorbed onto activated carbon filter. But can block the release out by storing in a Tedlar gas sampling bag. We was able to reduce the radiation exposure of the worker by efficient radiation protection.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.1571-1578
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• 2015

The cleaning characteristics of pulse air jet type cleaning system which is widely applied in the industries were identified by utilizing the computational fluid dynamics (CFD) and the cleaning performance in modified shape of dedusting unit was compared in this study. The review on each shape of cleaning part showed that the case of installing the nozzle on the blow tube (Case-3) and the case of installing the double intaking tube to the venturi (Case-4 and Case-5) were more excellent than the structure (Case-1). Also, the optimal venturi shape was designed and examined its applicability to the site in a pilot scale plant. A combined system of a blow tube and a venturi proposed by this study turned out to be very effective for concentrating an cleaning air compared to existing systems, such as using only blow tube and combines the blow tube and venturi. In addition, as a result of installing and testing a venturi proposed by this study, the cleaning frequency and cleaning time were much improved compared to a case of using a commercial venturi that is under use at the industrial sites.

• 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.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.14 no.2
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• pp.57-63
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• 2008

The effects of airtight containers and zipper bags on the freshness extension of pine nuts (Pinus koraiensis) were studied at 4 and $25^{\circ}C$. Changes in total microbial growth, 2-thiobarbituric acid(TBA), color, and sensory quality were evaluated during storage. Total bacterial counts of the samples continuously increased over 28 days for airtight containers and 56 days for zipper bags, and then decreased at 70 days because the lack of air could affect the inhibition of the aerobic microbial growth. However no significant differences were observed between airtight containers and zipper bags. TBA values continuously increased with storage time, but there were no significant differences between the airtight containers and zipper bags during storage. Color changes and sensory evaluation analyses showed that the data revealed similar results for both packaging systems over the storage time. Therefore, it has been concluded that airtight containers and zipper bags could be used as a good packaging system to extend the shelf life of pine nuts by controlling the microbial growth, but the packaging systems of the airtight containers and the zipper bags was not significantly affect the quality parameters for 2-thiobarbituric acid(TBA), color, and sensory quality.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3792-3799
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• 2012

The dedusting characteristics of pulse air jet type dedusting system which is widely applied in the industries were identified by utilizing the computational fluid dynamics (CFD) and the dedusting performance in modified shape of dedusting unit was compared in this study. The review on the dedusting air volume, air stream distribution and inflow velocity distribution on each shape of dedusting part showed that the case of installing the nozzle on the blow tube (Case-3) and the case of installing the double intaking tube to the venturi (Case-4 and Case-5) were more excellent than the structure (Case-1) which is widely applied in the field in its amplification effect on the air volume and extension of stream width. The specification of venturi was decided to apply the selected Case-5 for the option of the commercial back filter. It is considered that the dedusting air volume will be maintained in maximum in the case of 50 mm and 90 mm for the diameter of internal and external intaking pipe respectively.