• 대한가정학회지
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• 제32권5호
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• pp.217-227
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• 1994

The Korean clothing industry according to historical documents has a long and deep history. We can deduce the fact that cloth in material was self reliant during the pre-historic period. Although we can not find evidence of clothing material trade from the Three Kingdom era we find active trade with Kang, Jin of China and Japan followed by the spread of Korean clothing material manufacturing skills to Japan. Meanwhile the actual progress of the clothing industry came with the manufacture of cotton stuff in the Koryo era and the official and unofficial trade which brought import and export activity to Korea. Also the manufacture of clothing material by women labor although backward as it may be can be seen as stroug evidence that women labor continuously kept up the development of Korean industry. After the Koryo dynasty trade in clothing material and other clothing items contined with other nations. In conclusion we must not think that the Korean clothing industry started active development from the Chosun dynasty. It is important that we realize this fact and looking at the continuous progress of the Korean clothing industry through historical documents from early history to the Chosun era we rightly evaluate history and be proud of this legacy and also reevaluate the wrong views held before.

• 한국군사과학기술학회지
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• 제4권1호
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• pp.124-136
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• 2001

In this paper, we designed and manufactured the Ku-band circular waveguide antenna to do wireless communication with a ground radar as on-board antenna of missile. Using the MATLAB and the HFSS, we designed the circular polarizer which has a characteristic of circular polarization and broadband using the capacitive pin method, the feeder to feed coaxial line to circular waveguide, and a stopper to prevent a conductor material from being inserted. Then we simulated the designed antenna using the HFSS, obtained the gain and the radiation pattern. Because of a difficulty of manufacture, we established a manufacture process procedure. Antenna is manufactured with this procedure, test results of the manufactured antenna are the axial ratio of 1.37 ~ 1.72, the 3 ㏈ beamwidth of $72.23^{\circ}{\sim}78.54^{\circ},$ and the gain of 3.26 ~ 4.61 ㏈ within frequency band. We knew that these results are similar with simulation results. Also, we confirmed that the manufactured antenna is satisfied with requirement conditions through performance test, environmental test and flight test.

• 대한토목학회논문집
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• 제38권6호
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• pp.1001-1012
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• 2018

국내 철도차량부품 제조 중소기업은 250여 개의 관련업체가 있으며 자체 기술력을 보유하기 보다는 외국 기술과 제품을 수입하여 철도차량의 부품을 제작 납품하는 형태로 생존하고 있다. 이로 인해 철도 핵심부품 산업은 해외 의존성이 높은 상황이다. 이에 정부에서는 철도차량부품 제조 중소기업 지원을 위해서 다양한 정책적 지원을 강화하고 있지만, 정부의 지원 정책이 철도차량부품 제조 중소기업이 안고 있는 문제점과 애로사항을 충분히 해결하지 못하고 있다. 철도차량부품 제조 중소기업이 국가경제의 경쟁력 강화에 기여할 수 있고 이들을 효과적으로 지원하기 위해서는 기술사업화 과정에서 중요한 촉진요인이 무엇인지 명확히 파악할 필요가 있다. 이에 본 연구는 철도차량부품 제조 중소기업의 기술사업화를 촉진하는 10개의 요인을 추출하였으며, 이들 지표의 중요도를 AHP (Analytic Hierarchy Process)를 이용하여 분석하였다. AHP 분석결과, 기업내부 요인이 가장 중요한 요인으로 나타났으며, 그 하위 항목으로는 '사업화 능력'이 가장 중요한 항목으로 분석되었다. 본 연구의 내용과 결과는 공공 연구기관 및 철도차량부품 제조 중소기업 지원 기관인 철도 운영기관의 기술사업화 지원 프로그램 기획과 지원 정책을 수립할 때 유용하게 이용될 수 있을 것으로 기대된다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1710-1716
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• 2008

The Loop Heat Pipe (LHP) operates to pump the working fluid by means of the capillary force in a wick structure. Particularly, it is difficult to design and manufacture the evaporator consisted of a grooved container and a compensation chamber as well as the wick structure. This study is related to design and manufacture the grooved container coupled with wick structure, the properties of the wick structure such as the permeability, the porosity, and the maximum capillary pressure were measured to apply the cooling technology for Insulated Gate Bipolar Transistor (IGBT). The container of the LHP was manufactured by the electrical discharge process and the wick structure was sintered with the nickel particle by an axial-press apparatus with the pulse electronic discharge. As results, the properties of the wick were experimentally obtained about 60% of the porosity, 35kPa of the maximum capillary force and $1.53{\times}10-13m2$ of the permeability.

• 한국기계가공학회지
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• 제10권4호
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• pp.121-126
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• 2011

An accumulator placed on the refrigerant cycle pipe lines is a part to relax fluctuations of pressure within the pipe lines and stabilize refrigerants flowed into pipe. The accumulator has been mainly manufactured by the process of tube spinning using CNC(Computer Numerical Control) lathe. However, this process has the defects which are low productivity per hour and high cost. For that reason, tube end-forming using roll die is actively being developed, recently. The purpose of this study is to develope the tube end-forming process using roll die in order to manufacture the accumulator for the refrigeration pipe lines. First, the process design of tube end-forming was performed based on specification of product, and then was verified with FE analysis. Also, the effects of friction coefficient and revolution speed of roll die on forming load were investigated. The analytical results were applied in the final process design of tube end-forming. Finally, tube end-forming test was carried out to verify the validity of the FE analysis and the process design.

• Journal of Microbiology
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• 제39권1호
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• pp.67-73
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• 2001

A validation study was conducted to evaluate the efficacy and mechanism of the cryo-precipitation, monoclonal anti-FVIIIc antibody (mAb) chromatography, Q-Sepharose chromatography, and lyophilization steps involved in the manufacture of high purity factor VIII (GreenMono) from human plasma, in the removal and/or inactivation of hepatitis A virus (HAV). Samples from the relevant stages of the production process were spiked with HAV and subjected to scale-down processes mimicking the manufacture of the high purity factor VIII concentrate. Samples were collected at each step and immediately titrated using a 50% tissue culture infectious dose (TCID$\_$50/) and then the virus reduction factors were evaluated. HAV was effectively partitioned from factor VⅢ during cryo-precipitation with the log reduction factor of 3.2. The mAb chromatography was the most effective step far removal of HAV with the log reduction factor of $\geq$4.3. HAV infectivity was not detected in the fraction of factor VⅢ, while most of HAV infectivity was recovered in the fractions of flow through and wash during mAb chromatography. Q-Sepharose chromatography showed the lowest efficacy for partitioning HAV with the log reduction factor of 0.7. Lyophilization was an effective step in inactivating HAV with the log reduction factor of 2.3. The cumulative lag reduction factor, $\geq$10.5, achieved for tile entire manufacturing process was several magnitudes greater than the potential HAV load of current plasma pools.

• 한국환경보건학회지
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• 제20권3호
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• pp.1-12
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• 1994

Wastewaters being treated and final effluents were collected from 3 wastewater treatment plants of petrochemical industries, from August 31 to October 4, 1993 in an interval of 10 days, and further analysed by GC/FID to investigate discharge situation and removal efficiency on polycyclic aromatic hydrocarbons. The results were as follows: 1. The PAHs 294.57 $\mu$g/l were discharged in primary treatment effluent of plant A to manufacture vinyl acetate resin and acryl, and removed 54.51% by aeration and totally 84.71%. 2. The PAHs of the highest concentration were discharged in primary treatment effluent of plant B to manufacture PS resin and ABS resin, but removed 91.65% by activated sludge process and 98.19% by activated carbon to discharge PAHs of the lowest concentration comparing to another treatment operations. 3. The PAHs 99.96 $\mu$g/l of the lowest concentration were discharged in wastewater of plant C to manufacture epoxy resin, and removed 80.48% by activated sludge process. 4. B treatment system including activated carbon showed up the best removal efficiency of PAHs. Activated carbon therefore, seems to be effective as tertiary treatment. 5. Correlation coefficient of components to total PAHs was generally low, and correlation coefficients of phenanthrene, pyrene and acenaphthylene to total PAHs were each 0.98, 0.97 and 0.80, respectively. Correlation coefficient of the sum of phenanthrene, pyrene and acenaphthylene to total PAHs was 0.99, so that the sum of phenanthrene, pyrene and acenaphthylene was available as index to estimated total PAHs. 6. Phenanthrene and Chrysene were very well treated biologically and acenaphthylene and fluoranthene were untreated biologically. 7. Considering EPA standards, it seems that the concentration of phenanthrene, pyrene, fluoranthene, and benzo(k)fluoranthene is high level.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권6호
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• pp.340-346
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• 2002

The purpose of the present study was to examine the efficacy and mechanism of the PAB (para-amino benzamidine) affinity column chromatography, Viresolve NFP virus filtration, pasteurization (60$\^{C}$ heat treatment for 10 h), and lyophilization steps employed in the manufacture of urokinase from human urine as regards the removal and/or inactivation of the hepatitis A virus (HAV). Samples from the relevant stages of the production process were spiked with HAV and subjected to scale-down processes mimicking the manufacture of urokinase Samples were collected at each step, immediately titrated using a 50% tissue culture infectious dose (TCID$\_$50/), and the virus reduction factors evaluated. PAB chromatography was found to be an effective step for removing HAV with a log reduction factor of 3.24. HAV infectivity was rarely detected in the urokinase fraction, while most of the HAV infectivity was recovered in the unbound and wash fractions. HAV was completely removed during the Viresolve NFP filtration with a log reduction factor of $\geq$ 4.60. Pasteurization was also found to be an effective step in inactivating HAV where the titers were reduced from an initial titer of 7.18 log$\_$10/ TCID$\_$50/ to undetectable levels within 10 h of treatment. The log reduction factor achieved during pasteurization was $\geq$ 4.76. Lyophilization revealed the lowest efficacy for inactivating HAV with a log reduction factor of 1.48. The cumulative log reduction factor was $\geq$ 14.08. Accordingly, these results indicate that the production process for urokinase exhibited a sufficient HAV reducing capacity to achieve a high margin of virus safety.

• 한국환경과학회지
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• 제29권3호
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• pp.307-318
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• 2020

The integrated permit system is applied to class 1 and 2 atmospheric and water pollutant discharge facilities in 19 sectors. The fertilizer sector should receive a permit for a period of four years, from 2019 to 2023. The purpose of this study is to investigate the differences between the Korean Best Available Techniques (BAT) reference document (K-BREF) and the European Union BAT reference document (EU-BREF) in terms of the process and emission characteristics of fertilizer manufacture. K-BREF is written by focusing on products, whereas EU-BREF is produced on focusing on manufacture process. There are five types of BATs(best available techniques economically achievable) in Korea. These BATs selected mainly to recover and reuse raw meterials and save energy. The number of BATs and BAT-AELs(BAT associated emission level) in K-BREF is smaller than that in EU-BREF. We suggest that BATs and those environmental management parameters in Korea need to further reflect the emission characteristics in the fertilizer sector.

• 한국기계가공학회지
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• 제10권5호
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• pp.58-64
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• 2011

In this paper, research on the manufacturing technology of hexagonal structure core is investigated. Also the optimal forming process of the honeycomb core is developed and the rolling process is analyzed using finite element code, $DEFORM^{TM}$-3D. The standard honeycomb has a uniform hexagonal structure defined by the material, cell size, cell wall thickness and bulk density. Honeycomb core products can be made from any thin, flat material. The most common cell configuration is the hexagon but there are many other shapes for special applications. Because of the precision shape and the thin thickness, the honeycomb core is not easy to manufacture in the metal forming process. Through this study it was confirmed that after the rolling process, the section of honeycomb close to the standard shape can be obtained. This result is reflected to the manufacturing process design for the honeycomb core.