• Journal of Animal Science and Technology
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• v.51 no.5
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• pp.427-432
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• 2009

This study was undertaken to screen a high xylanase and mannanase producing microbes. In the first experiment, screening was undertaken against 50 samples of microorganisms having xylanase and mannanase activities from soil and fallen leaves. The screening process has focused on picking out fungi having high xylanase and mannanase activities under the solid-state fermentation. The xylanase and mannanase activities of 6 screened microbes were 0.9~1.6 unit/mL and 0.2~0.4 unit/mL, respectively, under the submerged fermentation condition. However, under the solid-state fermentation, xylanase and mannanase activities were 103.7~220.0 unit/g and 20.1~40.3 unit/g, respectively. Finally one microbe (E-3) was selected and its xylanase and mannanase activities were 197.3 unit/g and 39.9 unit/g, respectively. The morphological and molecular biological classification of E-3 showed 99% homology with the Aspergillus niger.

• Membrane Journal
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• v.17 no.4
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• pp.359-368
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• 2007

The copolymer membranes, poly(vinylidene fluoride-hexafluoropropylene) (PVdF-HFP) were prepared by phase inversion method using as an additive with N,N-dimethylformamid as a solvent. The pores are generated during the solvent and non-solvent exchange process in the coagulation bath filled with non-solvent (distilled water). The highest porosity of the membrane was 60%. The surface and cross-section of the membranes was observed with a scanning electron microscopy (SEM). The mechanical property of the membrane was determined by using an universal testing machine (UTM). Tensile strength of measured membranes is presented the maximum 6.57 MPa at 30 wt% of PVdF-HFP.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.75-81
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• 2005

The GNUnet in P2P system have solved an anonymous(publisher, storer, demander); a service of condition equal for peer. The GNUnet for an anonymous has separated a file and dispersed to the network. But, the 1Kbyte block size of the GNUnet is a creation of many additional block. I and R block has created with indirect point of D block The waste of I and R block appeared to 4% of the original file and the additional network traffic for the block transmission. To resolve the problems, this paper proposes an new scheme of file splitting distribution using P2P networks with the new GNUnet protocol, The GNUnet support minimization of the additional block and for a network traffic. It proposed an efficiency improvement of encording block and routing algorithm.

• Korean Journal of Materials Research
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• v.29 no.11
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• pp.697-702
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• 2019

In this study, using a wet chemical process, we evaluate the effectiveness of different solution concentrations in removing layers from a solar cell, which is necessary for recovery of high-purity silicon. A 4-step wet etching process is applied to a 6-inch back surface field(BSF) solar cell. The metal electrode is removed in the first and second steps of the process, and the anti-reflection coating(ARC) is removed in the third step. In the fourth step, high purity silicon is recovered by simultaneously removing the emitter and the BSF layer from the solar cell. It is confirmed by inductively coupled plasma mass spectroscopy(ICP-MS) and secondary ion mass spectroscopy(SIMS) analyses that the effectiveness of layer removal increases with increasing chemical concentrations. The purity of silicon recovered through the process, using the optimal concentration for each process, is analyzed using inductively coupled plasma atomic emission spectroscopy(ICP-AES). In addition, the silicon wafer is recovered through optimum etching conditions for silicon recovery, and the solar cell is remanufactured using this recovered silicon wafer. The efficiency of the remanufactured solar cell is very similar to that of a commercial wafer-based solar cell, and sufficient for use in the PV industry.

• Korean Journal of Microbiology
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• v.43 no.3
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• pp.217-221
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• 2007

The domestic cultured Campbell's Early and Geubong grapes were fermented far the production of red wines with the isolated wild yeast Saccharomyces cerevisiae IJ850. For the isolation of wild yeast, Geubong and Campbell's Early grapejuices were naturally fermented at room temperature for 6 days without adding stater culture. The strain isolated from Geubong which has 1.8 times higher fermentative ability than the strains isolated Campbell Early was selected. The selected strain was identified by using 26S rDNA sequencing. The strain showed 99.7% of similarity with Saccharomyces cerevisiae and thus identified as Saccharomyces cerevisiae IJ850. It was investigated the fermentative ability as the start culture. For the production of grapewine, the final sugar concentrations of grapejuices were adjusted to the $25^{\circ}Brix$ with anhydrous glucose. The grapejuices were fermented at room temperature for 10 days in the air-locked bottles filled with $CO_2$ gas. The final yield and alcohol concentration of Campbell's Early and Geubong grapewines fermented with the isolated wild yeast were 80.8%, 11.0% and 87.8%, 13.0%, respectively. Between the isolated wild yeast S. cerevisiae IJ850 and the commercial yeast S. cerevisiae EC1118, total acidities of grapewines produced with wild yeast were lower than those produced with the commercial yeast. The pH values and the values of color analysis of grapewines produced with both strains were similar. The total phenol contents of campbell's Early and Geubong wines produced with the isolated yeast and the commercial yeast were obtained in the range of 75 to 125mg/L. In conclusion, S. cerevesiae IJ850 isolated from the domestic cultured Geubong grape is able to use to produce grapewines as stater culture.

• 한국약용작물학회:학술대회논문집
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• 2011.04a
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• pp.348-349
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• 2011

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.97-99
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• 2009

본 논문에서는 유기성 폐기물을 처리하는 과정에서 발생하는 응축수의 제조 방법 및 성능들을 보고하였다. 유기성 폐기물을 밀폐된 교반조에서 수증기에 의한 연속적인 가열을 통하여 고액을 분리하여 열교환기를 거쳐 액상으로 배출되는 것이 응축수 제조 공정이며, 다량의 유기물을 포함하기 때문에 액비, 탈취제 및 하수처리장에서 외부탄소원으로 활용 가능하다.

• Journal of the korean veterinary medical association
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• v.20 no.2
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• pp.103-108
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• 1984

A total of 359 cultures of Staphylococcus were isolated from no raw milk samples in stock farms of Gyeongnam province from December, 1981 to May, 1982. Some biochemical properties and antimicrobial drug susceptibility of the isolaes were studied with the

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.10a
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• pp.210.2-210
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• 1978

전보의 glutathione의 최적 추출조건에 의한 추출액을 이온교환수지(Dowe xl-x2, Dowex 50w-x8)에 통과시켜 NAD와 glutathione을 분리하여 각각 paper chromatography로 확인한 결과 authentic Rf치와 일치하였다. 또 glutathione 함유액 부분을 2가구리 화합물로 처리한 동염처리 정제법을 이용하여 순수 glutathione 함유액을 얻었다. 또 chelate제도 sodium gluconate를 0.02％ 처리할때 glutathione 최종 수율이 66.2％에서 76.8％로 증가하였다. 이 순수용액을 50％ ethanol로 처리하여 crude glutathione 결정을 얻었다.

• The Korean Journal of Financial Management
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• v.10 no.2
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• pp.83-115
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• 1993

본 연구는 외국인(세법상 비거주자와 외국법인을 통칭한다. 이하 같음)의 우리나라에 대한 주식투자에 관한 세제를 고찰한 것이다. 연구의 방법으로서는 문헌조 사에 의해 관련세제를 살펴보고 설문조사에 의해 이해관계자의 의견을 조사하였다. 연구의 결과는 주식보유시의 배당소득에 대하여 제한세율의 적용대상을 조약별로 통일시키고 국내사업장없는 경우의 원천징수세율을 인하함이 필요하며, 또 주식처분시의 주식양도차익에 대하여 원천분리과세 뿐 아니라 신고분류과세도 선택할 수 있도록 하는 것 등이 필요한 것으로 나타났다.