• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.281-288
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• 2005

실리콘웨이퍼 제조공정에서 발생되는 초산, 불산 및 질산을 함유한 폐혼산으로 부터 각 산을 분리한 후 재활용하기 위하여 기초 실험을 실시하였다. 용매추출 법을 이용하여 초산, 불산 및 질산을 분리하기 위해 최적 추출제를 선정 하였고, 단일 성분에서의 추출 및 탈거특성에 관해 조사하였다. 또한, 이성분계 혼합산에서 분배비를 조사하여 상호 분리성에 대해 검토하였다. 실험 결과 인산염계 추출제는 고급 알코올에 비해 각 산의 추출 능력이 높다는 것을 확인하였다. 초산과 질산의 이성분 혼합액에서는 고급 알코올을 사용하면 초산이 분배비가 높아 선택적으로 추출되는 것을 확인하였고, 초산과 불산의 이성분 혼합액에서도 인산염계 추출제 보다 고급 알코올 사용시 초산의 분배비가 높아 선택적으로 추출됨을 확인하였다. 한편, 질산과 불산의 혼합액에서는 인산염계 추출제를 사용하여 질산이 선택적으로 추출됨을 확인하였다.

• Journal of the Korean association of regional geographers
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• v.19 no.1
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• pp.181-200
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• 2013

The Chinese Geography Standards for Senior Secondary Schools(trial) was released in 2003. The Standards put forward some changes for senior geography education, the changes in geographical education are reflected explicitly and implicitly by the textbooks. The purpose of this descriptive study was to review of the improvement of Chinese senior geography education by analyzing contents organization and coherence of the new standards-based geography experimental textbooks. The results of study are as follows. The textbooks adopts a student-centered approach through the way of 'more chapter topics with slimmed contents' and by introducing four type activities, geographical inquiries. These student activities are implicity encourages students' active acquisition of geographical knowledge what they have learned in their real lives. The organic coherence of the textbooks' contents rests on the compulsory and the elective subject relating to diversification of the learning areas. The organic coherence between the compulsory and the elective subject rests on diversification of the learning areas. More, looking at the arrangement of the four basic concepts(population, resource, environment, sustainable development) among the textbooks, it was imbalanced by subject.

• Journal of Korean Society of Forest Science
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• v.99 no.4
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• pp.479-486
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• 2010

We analyzed the relationships between the daily yield and quality of pine-mushroom to predict the annual production pattern and unit price of the mushroom with the records of pine-mushroom trade at Yeongdeok forestry cooperative's market for nine years (2000~2008). Although there were some exceptions due to extreme drought or extraordinary temperature, the production ratio of high quality (first and second grade) was more than 50% in early stage and decreased, while that of low quality (pileus opened and defected ones) showed increasing pattern after the production reached in peak. The ratio of high quality and that of low quality were reversed 1~9 days before the mushroom production reached the acme of daily yield, which allowed us to predict that the mushroom production would be decreased when the ratio of low quality overcomes that of high quality. The ratio of high quality preceded about 3~4 days prior to that of daily yield, and the mushroom yield showed significant correlations with the ratio of high quality mushroom prior to 3~4 days of the day with the coefficient larger than 0.5 (r=0.51 for 3 days and r=0.54 for 4 days). Thus, we concluded that the analysis of grade distribution of pine-mushroom at the market may provide a significant clue to predict production pattern of the mushroom. In addition, the price of high quality pine-mushroom showed clear negative correlations with the yield. Thus, the analysis may take a good role for the trading of pine-mushroom with providing information for predicting the price of pine-mushroom.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.11a
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• pp.58-63
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• 2002

콘크리트에 사용되는 재료들은 특성진전에 따라 콘크리트의 경제성에 따른 고내구성은 비교적 용이하게 되었고, 콘크리트 구조물도 대형화, 다양화, 고급화되어 특수한 용도로서의 사용이 늘어나고 있다. 여기에 주안점을 두어 음료병을 파쇄하여 콘크리트에 혼합했을 때 강도에 미치는 영향과 강도 특성을 알아보기 위한 것이다.(중략)

• Journal of the Korean Applied Science and Technology
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• v.16 no.2
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• pp.147-153
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• 1999

As main components of antifoamers, we were used fatty alcohols, fatty acid and fatty acid esters. Then the antifoaming properties on the particle size distribution, temperature and concentration for antifoamers was measured by Air Injection Method of ASTM under 1L/min air flow rate condition, and was measured surface tensions and emulsifying power of antifoamers. The antifoaming properties on the particle size distribution of antifoamers showed excellent antifoaming properties in the range of emulsion particle size from 5.5 to 6.8${\mu}m$. Surface tensions on the $10^{-2}$wt% aqueous solution of antifoamers was $33{\sim}34$ mN/m. And emulsifying power of fatty alcohol antifoamers showed good.

• Journal of Sericultural and Entomological Science
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• v.44 no.1
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• pp.37-41
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• 2002

The attaching treatment of sericin onto polyester fiber was attempted to improve its sanitary properties. Generally, sericin, a gummy material covering the outer layer of silk filament, is subjected to be removed during degumming process of silk textile process. For this study, sericin particle dissolved within the degumming waste water could be collected by sedimentation of polyaluminium chloride. It was revealed that sericin particle were attached onto the surface of polyester fiber evenly by treatment of glutaraldehyde, a crosslinking agent. A frictional static charge of the treated polyester fabric could be improved, while its hygroscopic property was little changed.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.05a
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• pp.197-201
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• 2003

플라스틱 제품은 경량이며 내후성, 내구성, 방음성, 단열성, 절연성 등이 우수하고 또한 발포가공에 의해 원료 폴리머의 사용량을 저감시켜 생산원가를 줄일 수 있다는 커다란 장점이 있다. 그러나 물리적인 강도, 가연성, 내열성 등의 한계점 때문에 그 용도가 제한되고 있는 실정이다. 형상 변경이 비교적 용이한 경량 구조체를 이용한 건축소재는 협소공간의 고도 이용과 건설 분야의 양적, 질적인 측면에서 급속한 성장으로 건축자재의 경량화, 고급화 및 다양화를 요구하고 있으며 이에 polyurethane, polyethylene, polystyrene 등의 플리스틱 및 foam 형태의 저밀도 고분자 건축소재의 사용이 급증되고 있다.(중략)

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.112-116
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• 2006

본 연구는 인간과 동물의 식욕조절, 에너지 대사, 체지방 축적 및 지방 대사에 핵심적인 역할을 담당하는 비만 유전자 leptin의 SNP를 검색하고, 이들 SNP 마커와 한우의 도체 및 육질형질들과의 연관성을 구명하여 고급육 생산 한우 조기 선발 및 육질 진단을 위한 분자 표지 마커로 활용하기 위하여 수행하였다. 한우 leptin 유전자의 exon 2 및 3번 영역을 포함한 염기서열 분석결과 총 3개의 SNP를 검출하였고, PCR-RFLP및 SSCP기법을 이용하여 SNP유전자형을 분석한 결과 exon 2 영역 내 C1180T SNP부위가 한우의 근내 지방도 및 등지방 두께와 유의적인 연관성(p<0.05)이 있는 것으로 나타났다. 따라서, 본 연구를 통해 개발된 한우 leptin 유전자의 특정한 SNP marker는 근내 지방도가 우수한 고급육을 생산하는 한우의 조기식별 및 마블링 등 육질진단에 매우 유용한 DNA 표지인자로 활용할 수 있을 기대된다.

• Journal of the Korean Geographical Society
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• v.40 no.5 s.110
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• pp.533-552
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• 2005

Human capital and higher education have been increasingly emphasized with the rise of a knowledge-based economy. Cities are recognized as places to attract human capital and spur economic development. Educated workforce supply is one of the critical parts to sustain IT industries, which have been leading recent economic development. This paper examines factors affecting geographies of educated workforce supply from colleges and universities to companies in U.S. metropolitan areas through questionnaire survey and interviews with IT companies and IT-related programs at colleges and universities. The results show that: (1) physical proximity between IT companies and colleges/universities enhances the degree of educated workforce supply from colleges/universities to IT companies; (2) IT companies which seek more specialized and rarer expertise recruit the workforce from colleges or universities over longer distance; (3) colleges and universities which offer a higher degree have geographically more extensive supply of educated workforce to IT companies than those which offer a lower degree; and (4) large IT companies have more geographically extensive supply of educated workforce to colleges/universities than small IT companies.

• KIPS Transactions on Software and Data Engineering
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• v.9 no.6
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• pp.195-204
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• 2020

Nowadays there are over 1.6 billion web pages and it is hard to get necessary results that user wants. Most search engines allow you to search with logical form to get accurate results. However, normal users are not familiar to search information as logical form. Therefore, they search in natural language rather than in complicated logical form. In this paper there are some suggestions to improve quality of searching results, converting natural language input by the user into logical form which can able to use advanced search engine. Users tend to make short searches due to the 'Simplicity' which is one of the features of the search form. Therefore we suggest history retrieval method; advanced version of previous suggestion to provide convenience to the normal users. We had improvement on accuracy of the search results converting natural languages to logical form and also can contain every keyword without missing any keywords using searching methods on this paper. It is expected that these search methods will contribute to the development of search engines.