• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3203-3207
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• 2012

The nucleophilic substitution reactions of diisopropyl chlorothiophosphate (5) with X-pyridines have been kinetically studied in MeCN at $35.0^{\circ}C$. The Hammett and Br$\ddot{o}$nsted plots for the substituent X variations in the nucleophiles show biphasic concave upwards with a break point at X = 3-Ph. The pyridinolysis rate of 5 exhibits great negative deviation from the Taft plot. A concerted $S_N2$ mechanism is proposed involving a change of the attacking direction of the X-pyridines from a frontside attack with the strongly basic pyridines to a backside attack with the weakly basic pyridines.

• Proceedings of the IEEK Conference
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• 2000.06d
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• pp.139-142
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• 2000

$\mu$BGA(Ball Grid Array) is growing in response to a great demand for smaller and lighter packages for the use in laptop, mobile phones and other evolving products. However it is not easy to find its defect by human visual due to in very small dimension. From this point of view, we are interested its development of a vision based automated inspection algorithm. For this, first a 2D view of $\mu$BGA is described under a special blue illumination. Second, a notation-invariant 2D inspection algorithm is developed. Finally a 3D inspection algorithm is proposed for the case of stereo vision system. As a simulation result, it is shown that 3D defect not easy to find by 2D algorithm can be detected by the proposed inspection algorithm.

• Transactions of Materials Processing
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• v.19 no.1
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• pp.32-37
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• 2010

Hydroforming has attracted a great deal of attention in the manufacturing industries for vehicles and transportation systems. Hydroforming technology contributes to weight reduction, increased strength, improved quality and reduced tooling cost. Hydroformed automotive parts used as structure components in vehichle body frame often have to be structurally joined at some point. Therefore it is useful if the hydroformed automotive parts can be given a localized attachment flange. For a given flange shape, a parting plane for the dies is established relative to which the various surfaces of the flange shape, in cross section, have no significant reverse curvature. In this study, hydroforming process for flange forming was proposed. FE analysis to form flanged circular shape and flanged rectangular shape was preformed with Dynaform 5.5. To accomplish successful hydroforming process design, thorough investigation on proper combination of process parameters such as tool geometry and hydraulic pressure has been performed and optimized. The results show that flanged automotive parts can be successfully produced with tube hydroforming.

• Journal of Microbiology and Biotechnology
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• v.4 no.2
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• pp.85-94
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• 1994

Lipase (triacylglycerol hydrolase, EC 3.1.1.3) is able to catalyze the hydrolysis of ester bonds of triacylglycerols at the interface between aqueous phase and organic phase containing substrate. With the rapid development of lipid biotechnology, lipase-catalyzed hydrolysis of lipids has a great concern from the industrial point of view. Owing to the reversible nature of the lipase, the reactions are also applied for glyceride synthesis, interesterification and resolution of racemic mixtures into optically active alcohols or acids. For all applications of the lipases, a reliable method for the determination of enzyme activity is required. Precise quantitative determination of its activity is essential as the basis of research and development of the bioprocess involving the enzyme. This article reviews the existing literature on the detection and determination of lipase activity from microbial, mammalian and plant sources.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.400-400
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• 2009

In a wide variety of high-voltage applications surface flashover plays major role in the system's performance and yet has not been studied in great detail for atmospheric conditions with modem diagnostic tools. surface flashover for both direct current and pulsed voltages in considered. within the setup, parameters such as geometry, material characteristics of the applied voltage can be altered. This paper review surface flashover of insulator, primarily in atmosphere. It discusses theories and models relating to surface flashover and experimental results. surface flashover of insulators in atmosphere generally is initiated by the emission of electrons from the cathode triple junction point (the region where the electrode, insulator, air). the electrode material was copper, and a AC voltage was applied between the electrodes. these results were compared with the surface flashover characteristic of epoxy.

• International Commerce and Information Review
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• v.8 no.2
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• pp.229-247
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• 2006

The company culture is becoming usual term in business management field. That organization culture of these phenomenon becomes resource of company competitive power indeed, it is basing to logic for important leading person for elevation with systemicity. also, great many scholars do research to subject that is change management of company administration and there are not much example that companies succeed in change actually despite had announced treatise etc. This research tries to synthesize several research subjects by single model regarding confrontation(culture collision) phenomenon between culture that can happen in company through literature research and example analysis basically. Specially, try to classify and divide this by specific developing and arrange in each type with using much this culture analysis in negotiation analytics. Through this problem and suggestion point by this confrontation way in this culture negotiation side and culture risk management side of administration make try to.

• Journal of the Korean housing association
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• v.16 no.6
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• pp.93-100
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• 2005

Turning into the 21st century, there are great demands for the diversification of housing style and amenity of housing, which include enhancing community life through proper collective environment. To solve these problems, cohousing has been introduced in Scandinavian countries. A primary goal of cohousing is the desire of residents to live in a socially supportive setting. People can do housework together and also can promote active mutual relationship among residents in the community. Physical feature of cohousing, in combination with social organization factors, nay serve to enhance or support the sense of community sought by residents. In this point of view, the purpose of this study is to consider the characteristics of planning factors applied to the community concept in cohousing. First consideration is to figure out the planning skills on community concept in housing community. Then, by making clear the planning factors on community concept in cohousing through case study, this paper could suggest a possibility of application of cohousing in Korea.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.3
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• pp.507-515
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• 2001

Tencel is a high quality cellulosic fiber, which is controlled and processed by an environmentally sound route. But, the point about tencel and the reason why it achieves its unique touch in its finished state is that it is a fibrillating fiber. That means it can take a great deal of punishment during the finishing process, which raise the fiber to produce the characteristics handle, without destroying the cloth. The aim of cellulase treatment is to improve appearence of tencel, plus the fiber ends protruding from the fabric surface. But enzymatic hydrolysis can weakens the fiber ends and changes the properties of fabrics. This study examined about the changes of properties according to several conditions and effect of cellulase to fibril of tencel. The results are as follows. The weight loss was occurred, tensile strength was decreased, softness was increased. And cellulase treatment reduced amount of fibril.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.452-455
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• 2005

We have studied the prearranged plan and the economy of a candidate site for the development of small hydro power. And also we have confirmed its economy by suggesting the technology of the unmanned operation and the selection of the water turbine generator which has a great efficiency. working rate and suitability to the topographical characteristics of various development sites, for example, irrigation reservoirs, water works pipes, sewage systems and cool ing water of a steam power stat ion. Besides we give more examples of the select ion of Francis, propeller turbine and induction generator which can achieve a maximum of power production at a minimum construction cost. With a water turbine which runs at the low head we are able to suggest many programs to boost a development of small hydro power more economically.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.93-93
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• 2003

Tungsten and tungsten heavy alloys have widespread application as radiation shielding devices and heavy duty electrical contacts. High density and good room temperature mechanical properties have generated interest in evaluating tungsten and tungsten alloys as kinetic energy penetrators against armor. Nowdays ultra fine-grained tungsten powders are in great interest because higly dense structures can be obtained at low temperature, pressure and lower sintering time. Several physical md chemical methods are available for the synthesis of nanometric metal Powders: ball milling, laser abalation, vapor condensation, chemical precipitation, metallic wire explosion i.e. However production rates of the above mentioned methods are low and further efforts are needed to find out large-scale synthesis methods. From this point of view solid state combustion method ( known as SHS) represents undoubted interest.