• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.101-102
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• 2000

반도체 생산에서 암모니아는 정밀성을 요구하는 공정 특히, 광증폭 공정에서 산과 반응하여 불량을 일으키는 주 원인이며, 고메모리로 갈수록 청정도 기준이 엄격해져서 1 ppbv 이하의 농도를 검출할 수 있는 기술이 요구되고 있다. 현재 반도체 회사에서의 암모니아 분석은 임핀저를 이용하여 가스를 포집한 후 이온크로마토그래피로 분석 하고 있으나, 이는 많은 시간과 인력이 요구되며, 실시간 분석이 어렵기 때문에 반도체 클린룸의 관리에 어려움이 있다. (중략)

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.07a
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• pp.209-214
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• 2002

현재 시중에 유통되고 있는 쌀의 표면에는 육안으로 잘 보이지는 않지만 가공과정에서 발생된 미세 쌀겨나 이물질이 다소간 부착되어 있기 때문에 이들로 인해 저장성 저하를 초래하고, 또 소비자가 밥을 짓기 위해서는 씻어야 하는 번거로움이 있다. 물론 미곡가공시설들이 깨끗한 쌀을 공급한다는 취지에서 연미기를 통과한 것을 청결미라는 브랜드로 보급하고 있지만, 이 쌀들이 과연 어느 정도의 청결도를 갖는지에 대해서는 생각해볼 여지가 많다. (중략)

• Proceedings of the SAREK Conference
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• 2007.06a
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• pp.208-208
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• 2007

• Journal of Welding and Joining
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• v.12 no.2
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• pp.20-27
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• 1994

The laser marking system is widely used in many industrial manufacturing companies as an effective process, because it is versitile, clean, and fast to run. Minimal heat deformation and zero tool wear can be obtained using fast and non-contact process of laser marking. As an introductory level, the basic knowledges about laser marking system layout and its components are presented with diagrams. The effects, requirements, and application example of laser marking process are also described in this paper.

• Clean Technology
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• v.12 no.1
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• pp.27-35
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• 2006

Main compositions of powder paint based on thermoset type epoxy resin consist of epoxy resin for powder coating, curing agent, filler and pigment. The curing system used in this study was based on diglycidyl ether of bisphenol-A (DGEBA) and dicyan diamide (DICY). The curing behavior and rheological properties of powder coating material were investigated using DSC and rheometer, respectively. And the adhesion strength between steel and powder coating material was measured using lap shear geometry. The optimum formulation of epoxy powder paint obtained from this study was base resin of 100 phr, DICY of 6 phr, $CaCO_3$ of 20 phr, and $TiO_2$ of 10 phr.

• Journal of ILASS-Korea
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• v.20 no.2
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• pp.88-94
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• 2015

Recently, exhaust gas regulation has been gradually strengthened due to depletion of fossil fuels and environmental problem like a global warming. Due to this global problem, the demand for eco-friendly vehicle development is rapidly increasing. A clean diesel vehicle is considered as a realistic alternative. The common-rail fuel injection system, which is the key technology of the clean diesel vehicle, has adopted injection strategies such as high pressure injection, multiple injection for better atomization of the fuel. In addition, the emission regulations in the future is expected to be more stringent, which a conventional engine is difficult to deal with. One of the way for actively proceeding is the study of alternative fuels. Among them, the bio-diesel has been attracted as an alternative of diesel. So, in this study, spray characteristics of bio-diesel was analyzed in the common-rail fuel injection system with three injectors driven by different operating mechanism.

• Clean Technology
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• v.21 no.2
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• pp.90-95
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• 2015

Digital microfluidic electroporation system was used for the transformation of microalgae and we have obtained higher transformation efficiency and viability than that of conventional method. Key parameters of electroporation such as pulse voltage, number, and duration time were systematically investigated for two different microalgal strains with and without cell wall. We have found that cell wall does not always have negative effects on the gene transformation of microalgae. Parallel processing of proposed digital microfluidic electroporation was demonstrated together with on chip culture of microalgae.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.1
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• pp.7-14
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• 2014

The core of the automotive industry's strategy to handle the climate change can be explained as the development and distribution of the vehicles with high fuel efficiencies and low emission. Clean Diesel, hydrogen fuel cell, electric, and especially hybrid power-train vehicles have been actively studied. This paper dynamically analyzes the performance of a hybrid system's five driving modes. The research subject consists of one engine, two electric motors, two simple planetary gears, and one compound planetary gears with five clutches. To define the steady state equation of the system, interaction formulas of five driving modes are introduced with motion variables and torque variables. These formulas are then used to analyze the speeds, torques, and power flows of each mode.

• Journal of the Speleological Society of Korea
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• no.89
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• pp.27-33
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• 2008

Solar energy is most green and clean, unlimited and sustainable energy source on the earth. It is almost 97% of imported consumer energy in Korea. Because of resource poor nation, it is necessary to do their best to make alternative energy to allot their deficiency of the matter in hand of energy resources of petroleum. In a point of view of this problems, the natural solar energy should be improved by any methods as much, possible as we need. Photovoltaic generation with solar tracking system for obtaining optimal power is one of most benefit equipment to improve power of solar-cell panel producing clean electric power efficiently. Solar tracker is a device for orienting a solar photovoltaic panel toward the sun perpendicularly to sunlight, especially in widely separated place. For this reason, we are very interested in developing the equipment system of tracker, specially in solar cell applications, obtaining a high degree of accuracy to ensure that the optimal sunlight could be directed precisely against to the powered device. As a result, it was obtained of 12.46 volts at 90$^\circ$toward solar panel and 9.44 volts at 45$^\circ$, furthermore, improved efficiency more than 30% of average output voltage between tracker system (12.41V) and fixed system (8.55V), respectively. It is also very useful for optimum power system of widely separated cave.

• Clean Technology
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• v.22 no.1
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• pp.62-72
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• 2016

These days, it seems to be a core time to build proactive prevention systems for small and medium sized enterprises due to the reinforced safety in the production process and the strong environmental regulations (ES) both at home and abroad. On the other hand, a network of experts that combines the industrial environment and production safety as well as even the knowledge services companies are not quite enough to prepare to support them. In this study, through a survey of experts the current statue of the convergence of industrial environment and production safety were reviewed, and the structure of knowledge ES cluster was proposed to overcome this current state. Detailed strategies such as the development and distribution of ES convergence methodology, ES efficiency analysis and an ES roundtable.