• The Korean Nurse
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• v.33 no.3
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• pp.33-39
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• 1994

• Journal of Information Management
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• v.18 no.3
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• pp.60-77
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• 1985

• Proceedings of the Korean Vacuum Society Conference
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• 2008.02a
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• pp.347-347
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• 2008

• Applied Microscopy
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• v.30 no.4
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• pp.337-345
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• 2000

Introduction of the buffer layer and the nitridation of a sapphire substrate were one of the most general methods employed for the reduction of lattice defects in GaN thin films Brown on sapphire by MOCVD. In an effort to improve the initial nucleation and growth condition of the GaN, reactive ion beam (RIB) of nitrogen treatment of the sapphire surface has been attempted. The 10 nm thick, amorphous $AlO_xN_y$ layer was formed by RIB and was partially crystallized alter the main growth of GaN at high temperature, leaving isolated amorphous regions at the interface. The beneficial effect of amorphous layer at interface in relieving the thermal stress between substrate and GaN film was examined by measuring the lattice strain value of the GaN film grown with and without the RIB treatment. Higher order Laue zone pattern (HOLZ) of $[\bar{2}201]$ zone axis was compared with simulated patterns and lattice strain was estimated It was confirmed that the great reduction of thermal strain was achieved by RIB process and the amount of thermal stress was 6 times higher in the GaN film grown by conventional method without the RIB treatment.

• Journal of the Korean Ceramic Society
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• v.38 no.10
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• pp.928-935
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• 2001

In this study, two kinds of activated carbon fibers were prepared from PAN-based stabilized fibers by physical activation with steam. The variations in specific surface area, amount of iodine adsorption and pore size distribution of the activated carbon fibers after the activation process were discussed. The activated carbon fibers were prepared by two different methods, namely a 1- and 2-step method. For the 2-step method, carbonization of fibers in $N_2$ atmosphere was carried out to make carbon fibers and then activated by steam. In normal two step steam activation, BET surface area of about $1019m^2/g$ was obtained in the study. In the 1-step steam activation process, the carbonization and activation were simultaneously carried out. In the one step steam activation, BET surface area of $1635m^2/g$ was obtained after heat-treatment at $990^{\circ}C$. However, nitrogen adsorption isotherms for oxidized PAN based activated carbon fibers that were prepared by both methods were type I in the Brunauer-Deming-Deming-Teller (BDDT) classification even though they have different BET surface areas, amounts of iodine adsorption and pore size distributions.

• Tuberculosis and Respiratory Diseases
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• v.43 no.3
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• pp.359-366
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• 1996

Background : Eosinophilic leukocytes are prominent cellular participants in the pathogenesis of allergic disease and asthma. Chemotaxis is still a very useful method in evaluating the response of human eosinophil to novel modulators. Degranulated mast cells and activated T lymphocytes are responsible for the pathophysiology of asthma and tryptase is one of most important proteases released after activation of mast cells. The purpose of this study was to investigate the actions of trypsin and chymotrypsin on eosinophils in terms of chemotaxis and activation. Method : Eosinophils were isolated by negative immunoselection from the peripheral blood of atopic donors. Chemotaxis was studied by using micro-Boyden chambers and ECP release was assayed by fluoroimmunoassay. Results : Eosinophil showed a chemotactic response to trypsin. Maximal chemotactic response was with $1000{\mu}g/ml$ trypsin ($56.52{\pm}14.50$/HPF) which was comparable to PAP. But chymotrypsin showed no significant chemotactic response to eosinophils. Trypsin at the concentration of 10, 100, $1000{\mu}g/ml$ induced secretion of ECP, which at the concentration of $10{\mu}g/ml$ represented about 2.7 times of the spontaneous rate of release. Soybean protease inhibitor reduced trypsin induced ECP release. Conclusion : Trypsin can induce chemotactic response to eosinophils and activation of eosinophils that can induce secretion of ECP. On the contrary, chymotrypsin showed no direct effect on eosinophils. We propose a role of trypsin on the chemotaxis and activation of eosinophils.

• Journal of Korea Technology Innovation Society
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• v.3 no.1
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• pp.85-99
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• 2000

벤처기업의 활성화에 따라 제기된 지적재산권을 포함한 기술의 경제적 가치평가방법에 대한 새로운 접근방법을 제시하였다 본 연구에서 제시하고 있는 지적재산권 특히 특허기술의 가치평가방법은 기술의 특성을 반영한 개별기술별 기술이전가치 측정에 있으며 추상적인 논의보다는 구체적인 사례를 중심으로 방법론을 적용시키고 있다 이는 기존의 기술가치평가방법론으로 사용되어온 정서적 가치평가방법에서 정량적인 사례를 제시함으로써 새로운 기술평가기법연구의 발전적인 계기를 마련하였다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.421-424
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• 2011

Thermal Analyses are conducted to measure various factors of a liquid fuel required for numerical analysis. Thermal Analyses are divided into two different methods of TGA (Thermo Gravimetric Analysis) and DSC (Differential Scanning Calorimetry). Non-isothermal experimental results are analyzed using by TGA. The results are filtered by a Freeman Carroll method. At the same time, chemical parameters of unknown liquid fuel, activation temperature and reaction order are measured to 6128.2 K and 1.4, respectively. Furthermore, the parameters can be obtained by various mathematical methods. It is found that tha parameters depend on the processing method.

• Journal of the Korean Institute of Gas
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• v.1 no.1
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• pp.120-126
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• 1997

The thermal decomposition of low density polyethylene(LDPE) and $25\%{\~}48\%$ chlorinated polyethylene(CPE) were studied using a dynamic thermogravimetry in the stream of nitrogen gas with 20ml/min. The mathematic method, differential (Friedman) and Integral (Ozawa) method were used to obtain value of activation energy of decomposition energy on the reaction. The activation energies evaluated by the above methods agree with each other very well. The maximum average activation energy calculated was 71.71kcal/mol. The thermal decomposition of LDPE and CPE were considered to be carried out by main chain scission and the thermogravimetric trace curve agree with the theoretical equation.

• Journal of the Korean Society for Library and Information Science
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• v.31 no.1
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• pp.105-124
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• 1997

The purpose of this study is to Investigate the factors haying an Influence on activating the Interlibrary loan between national university libraries. Data were collected by and questionnaires. To analyze the factors activating the Interlibrary loan, 1-test and regression analysis method Is adopted depending on the type of data collected. The findings of the study shows that the interlibrary loan can be more actively performed in the group of libraries to focus the subject background on library and Information science than the other group the number of lending cases is highly affected by collection size. the number of periodical titles, annually increased number of collections and periodical titles. Otherwise the number of borrowing cases is much less affected than the number of lending cases by the above factors : the interlibrary loan can be more actively conducted in the group of libraries using facsimile or PC than the other group.