• 한국재료학회:학술대회논문집
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• 한국재료학회 2007년도 추계학술발표대회 및
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• pp.157.2-157.2
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• 2007

• 한국환경복원기술학회지
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• 제9권3호
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• pp.76-81
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• 2006

The reinforcement of soil shear strength by nylon net as substitute materials simulating a fine root system was evaluated by soil strength parameters(apparent cohesion(c) and internal friction angle(tan${\phi}$), using simple shear tester which clearly depicts shear deformation and controls soil suction. And the results of shear test by using bamboo as a substitute materials simulating a main root system and using nylon net as a substitute materials simulating a fine root system were compared. The reinforcement of soil strength by nylon net are expressed by apparent cohesion more than internal friction angle. In addition the increment of apparent cohesion by nylon net reached a peak in suction 60 $cmH_2O$. Different from with bamboo, the possibility of the change on internal friction angle(tan${\phi}$) caused by the soil water condition was shown in shear strain 20% condition. These results show that the mechanism of reinforcement by substitute materials simulating root system may be different in the condition of various soil water content.

• Safety and Health at Work
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• 제9권3호
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• pp.360-364
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• 2018

Asbestos has been banned in many countries but many countries, including developing countries, are still using asbestos or materials containing asbestos. Substitute materials have been studied and developed over a long period of time because of the hazards of asbestos, and many people have recently shown interest in the hazards of substitute materials. However, comprehensive information about the types of asbestos substitutes, their use and health hazards, and references for the protection for the health of workers is limited. The purpose of this study is to provide people in the related industries with information on the types and health hazards of fibrous materials that can be used as asbestos substitutes. According to the patent resources from the United States and Europe, fibrous materials have been used to develop asbestos-free products since before 1980. Recently, the health hazards of asbestos substitutes have been assessed and many additional researches are required. However, only some of the substitute materials have been assessed for health hazards, and health hazard data has not been sufficient in many cases. Therefore, efforts should be made to minimize workers' exposure to substitute materials that do not contain asbestos.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2007년도 추계학술발표대회 및
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• pp.154.1-154.1
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• 2007

• Corrosion Science and Technology
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• 제8권1호
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• pp.40-43
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• 2009

We investigated the corrosion resistance of Zn and Cu coated steel pipes as a substitute for Cu pipe in an air-conditioner system. In addition, the galvanic corrosion tendency between two dissimilar metal parts was studied. The corrosion resistance of the Cu electroplated steel was similar to that of Cu, while the corrosion rate of the Zn electro- galvanized and the galvalume (Zn-55 % Al) coated steels was much higher and not suitable for Cu substitute in artificial sea water and acidic rain environments. Furthermore, the galvanic difference between Cu electroplated steel and Cu was so small that the Cu coated steel pipe can be used as a substitute for Cu pipe in an air-conditioner system.

• 한국재료학회지
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• 제16권5호
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• pp.336-340
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• 2006

Fluorspar has been essential flux in steelmaking process. The main effects of fluorspar addition are lowering of the viscosity and melting temperature of slag. In recent years, due to the increasing price and environmental problem of fluorspar, various types of fluorspar substitute have been investigated. In this study, iron oxide by-products such as sinter dust, basic oxygen furnace (BOF) sludge and mill scale were developed as a substitute in terms of waste recycling. Several plant trials were carried out by addition of briquetted substitutes of $4{\sim}6$ kg/ton to compare with the fluorspar of $0.7{\sim}1$ kg/ton. The substitutes showed a similar behavior of slag formation, phosphorus removal and MgO saturation content.

• 건축역사연구
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• 제31권4호
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• pp.7-16
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• 2022

Since the beginning of the second Sino-Japanese war in 1937, the entire Korean Peninsula has entered a full-fledged wartime system. Japan enacted laws that strongly regulate the distribution of various resources for war, and the same was implemented in Joseon. In particular, as iron, copper, lead, tin, and aluminum were mobilized as raw materials for military supplies such as weapons, private distribution decreased significantly, which had a great impact on the construction industry. As the use of metal such as steel as building materials requires permission from the provincial governor, it has become difficult to supply and demand except for some military facilities. In addition, the Japanese Ministry of Commerce and Industry encouraged research and development and manufacturing to promote the so-called "substitute goods industry" to make up for the shortage of supplies. Products with improved performance through chemical treatment by injecting only a small amount of the same raw material than before or using alternative raw materials have been developed. It was intended to overcome the limitations of lack of raw materials through the chemical industry. In terms of building materials, various substitutes were produced due to the incorporation of petrochemicals and the use of synthetic resins. This trend continued even after the end of the war and served as one of the backgrounds for R&D and production of new materials without returning to the "substitute goods."

• 한국축산시설환경학회지
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• 제6권3호
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• pp.133-140
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• 2000

This study was carried out to determine a suitable mixing rate to utilize the PDF as a bedding materials at the pigpens and investigate the effect of substitute processed dustproof fly-ash(PDF) on the odor. In proportion to the increase of substitute rate of the PDF, the utilizable period was extended, and there was a little change of the moisture in the bedding materials. At all the treatment of PDF, there was the significant effect on the maggots and parasites but it didn\`t hinder in the biodegradation. According to highly mixing rate, PDF decreased in the noxious gas ($NH_3$ and $H_2$S) emission. In conclusion, the mixing rate of 30% or above this substituted level will increase replacement terms, and reduce the sawdust cost and the pollutions of breed pigs.

• 한국보육지원학회지
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• 제9권3호
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• pp.209-228
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• 2013

본 연구는 경기도에서 활동 중인 국비지원 대체교사 49명과 도비지원 대체교사 53명 총 102명을 대상으로 대체교사 제도에 대한 인식이 어떠한지를 살펴보고 대체교사 제도의 활성화 방안을 모색해보고자 하였다. 본 연구결과는 다음과 같다. 첫째, 대체교사 지원사업에 참여하게 된 경로로 국비 대체교사는 인터넷 사이트, 도비 대체교사는 보육정보센터 홍보물이 높게 나타났다. 국비와 도비 대체교사 모두 '다른 활동과 병행하기 위해서'가 대체교사 지원사업 참여 동기로 나타났다. 둘째, 국비와 도비 대체교사 모두 '어린이집의 다양한 상황에 융통성 있게 대응하는 것'을 대체교사의 자질로 중요하게 보았다. 셋째, 국비 대체교사는 초과근무가 없고 보육교사에 비해 상대적으로 부담이 적다는 점을, 도비 대체교사는 다양한 어린이집 경험을 통한 전문성 향상과 초과근무가 없다는 점을 만족스러운 점으로 들었다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2008년도 추계학술발표대회 및 제15회 신소재 심포지엄
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• pp.44.2-44.2
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• 2008