• 한국식품과학회지
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• 제21권6호
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• pp.876-883
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• 1989

품질평가의 지표가 되는 메주의 성분 및 그 기준과 낱알형 개량메주의 품질수명을 측정할 목적으로 낱알형 개량메주를 제조하고 포장상태와 비포장상태로 저장하면서 저장기간 중 메주의 성분변화를 측정하였으며 또한 저장기간을 달리하여 간장담금을 한 후 90일간 숙성시키면서 숙성기간 중 간장덧액의 성분변화와 관능시험을 통하여 개량메주의 저장기간이 간장의 품질에 미치는 영향을 비교 검토하였다. 개량메주의 저장 중 총 질소함량은 변화가 없었으며 수분함량, amylase 역가 및 protease 역가는 감소하였고 $NH_2-N$ 함량과 $NH_3-N$ 함량은 증가하였다. 이들 중 저장기간 중에 변화가 큰 성분은 $NH_2-N$ 함량과 protease 역가였으나 간장발효의 가장 중요한 효소인 protease가 보다 좋은 지표성분임을 알 수 있었다. 또한 메주의 pretense 역가와 그 메주로 담근 간장의 품질은 밀접한 상관관계를 나타내었으며, 메주의 저장기간이 길어질수록 간장의 품질이 저하되었다. 낱알형 개량매주의 품질은 protease역가로 평가하였을 때 저장 15일된 메주가 가장 좋았으며 그 이후에는 저장기간이 길어질수록 메주의 품질이 저하되어 저장 90일 이후에는 비포장과 포장상태의 상대역가가 저장초기에 비하여 50%, 49%, 180일 이후에는 48%, 41%로 각각 감소함으로써, 메주의 품질수명 한계를 상대역가 50%(200O.D. at 660nm/g)로 정할 경우 낱알형 개량메주의 품질수명은 90일 정도인 것으로 추정되었다. 또한 본 실험조건하에서는 메주의 품질 및 간장덧액의 기호도 측면에서 포장상태 저장이 개량메주의 품질향상에 별다른 효과가 없는 것으로 생각되었다.

• 품질경영학회지
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• 제28권4호
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• pp.67-74
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• 2000

A Bayesian burn-in procedure is developed for imited failure populations in which defective items fail soon after they are put in operation and non-defective ones never fail during he technical life of the items. Sequential schemes guaranteeing pre-specified outgoing quality of a product are derived based on prior information on the quality of a product and accumulated failure information up to the decision point. A numerical example is also provided.

• 펄프종이기술
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• 제38권2호
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• pp.9-15
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• 2006

Neutral sizing is required for linerboard to solve the troubles in strength and process caused by recycled raw materials. AKD sizing efficiency can be influenced by process condition like white water quality, fines retention and so on. Therefore, this study was aimed to evaluate sizing performance of general and fast cure type AKDs using process water obtained from linerboard mill. To evaluate effect of process water quality on AKD sizing, white water was diluted with tap water at the different dilution ratios and UKP slurry was sized using the prepared water. Also, effects of inorganic and organic ion material on sizing were examined. When white water was used for stock forming, UKP sheet showed very low sizing degree. Sizing degree of sheet was increased with increase of dilution ratio because water quality was improved. Especially anionic organic material had a greater influence on AKD sizing than inorganic material. When white water quality was deteriorated, fast cure type AKD showed superior sizing performance to general type AKD.

• 한국물환경학회지
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• 제30권1호
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• pp.87-94
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• 2014

According to the technical guideline of water pollutant load management, the rainfall captured ratio which can be estimated by the empirical formula is an important element to estimate reduction loads of non-point pollutants water quality control basin. In this study, the rainfall captured ratio is altered to stormwater captured ratio considering its meaning in the technical guideline of water pollutant load management, and the new empircal formula of stormwater captured ratio is suggested. In order to do this, we calculate stormwater captured ratio by using the hourly rainfall data of seven urban weather stations (Busan, Daegu, Daejeon, Gangreung, Seoul, Gwangju, and Jeju) for 43 years. The regression coefficients of the existed empirical formula cannot reflect the catchment properties at all, because they are fixed values regardless of regions. However the empirical formula of stormwater captured ratio has flexible regression coefficients by runoff coefficient(C), so it is allowed to consider the characteristics of runoff in catchment. It is expected that reduction loads of storage based water quality control basin can be more reasonably estimated than before.

• Corrosion Science and Technology
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• 제23권4호
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• pp.278-282
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• 2024

Recently, hot rolled galvanized steel is widely used in automotive parts. As the paradigm of the automotive market has changed from fossil fuel vehicle to electric vehicle, the automotive industry needs more high-strength steels to reduce weights of automobiles. However, because high-strength steel contains high solute carbon, it is expected to have a risk of stretcher-strain on the surface due to dislocation trapping by solute [C] and [N]. Generally, galvanized steel is supposed to pass through a furnace around the temperature of Zinc pot to increase material temperature. Otherwise, the inhibition layer could not be formed. However, solute carbon and nitrogen are volatile enough to move around the furnace temperature. Moreover, the ratio of ferrite phase and precipitated Fe3C can be variable, resulting in yield point elongation related to the stretcher strain. Furthermore, the quality of the galvanized surface can be affected by a high temperature of the furnace. Although a relatively hot rolled galvanizing line furnace has a lower temperature than an annealing line furnace, it can affect various quality aspects. In other words, this paper aims to determine how these phenomena appear concerning furnace temperature.

• Corrosion Science and Technology
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• 제14권5호
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• pp.213-217
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• 2015

Recently, household electronic industries require environmentally-friendly and highly functional steels in order to enhance the quality of human life. Customers especially require both excellent corrosion and abrasion resistant anti-fingerprint steels for digital TV panels. Thus POSCO has developed new functional electro-galvanized steels, which have double coated layers with organic-inorganic composites on the zinc surface of the steel for usage as the bottom chassis panel of TVs. The inorganic solution for the bottom layer consists of inorganic phosphate, magnesium, and zirconium compounds with a small amount of epoxy binder, and affords both improved adhesion properties by chemical conversion reactions and corrosion resistance due to a self-healing effect. The composite solution for the top layer was prepared by fine dispersion of organic-inorganic ingredients that consist of a urethane modified polyacrylate polymer, hardener, silica sol and a titanium complex inhibitor in aqueous media. Both composite solutions were coated on the steel surface by using a roll coater and then cured through an induction furnace in the electro-galvanizing line. New anti-fingerprint steel was evaluated for quality performance through such procedures as the salt spray test for corrosion resistance, tribological test for abrasion resistance, and conductivity test for surface electric conductance regarding to both types of polymer resin and coating weight of composite solution. New composite coated anti-fingerprint steels afford both better corrosion resistance and abrasion properties compared to conventional anti-fingerprint steel that mainly consists of acrylate polymers. Detailed discussions of both composite solutions and experimental results suggest that urethane modifications of acrylate polymers of composite solutions play a key role in enhanced quality performances.

• 한국환경농학회지
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• 제15권4호
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• pp.506-519
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• 1996

The water quality in the rural areas is degrading due to a variety of causes such as the increase of the urban sewage and industrial wastes, the disposal of solid wastes, the growth of livestock waste, the growth of leisure facilities, the establishment of agricultural industry estates and etc. The water pollutants are scarce while the effluent is increasing from wide scattered sources. The technology specifically designed for the rural wastes water treatment plant needs to be implemented with improvement of agricultural water quality. 1. An integrated management measures against water pollution sources. The prevention of water pollution is the best measures in the environmental pollution. Hence, the most effective measures needs to be against the sources. Small-scale water treatment plants needs to be constructed in each village in the rural areas. As for the industrial effluent, the effluent discharge needs to be strictly monitored. Government subsidy for the establishment of treatment plant for livestock wastes is necessary. 2. The establishment of national-wide network for agricultural water quality. The network for agricultural water quality have been operated to conserve the agricultural water quality, and to develop management policies by the assessment of water pollution in the rural areas. The results of agricultural water quality network indicates that the water quality is degrading not only around urban areas but also in the distant rural areas, and the water quality at the pumping stations and weirs is worse than that of reservoirs. 3. The legal, systematic, and technical approaches for the agricultural water quality management. The actions currently implemented for the improvement of agricultural water quality involve temporary measures such as the improvement of irrigation facilities. These contingency measures are not effective in the long-term, and sometimes bring secondary pollution. Therefore, integrated measures covering the whole water environment such as the flow, quality, river morphology, aquatic ecosystem, and the surrounding environment, need be invented and implemented. Besides, the legal, systematic, and technical frameworks for the management are not fully established so far. The technology for the treatment of rural water pollution should be refined afterwards, and the research for the development of rural waste water treatment plant should be carried out.

• Corrosion Science and Technology
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• 제12권1호
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• pp.1-6
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• 2013

Recently Digital TV industry has drastically been moving the illuminating system, which causes an obvious product change from PDP and LCD to LED model to provide high-definition image. Due to strong competition in the digital industry, TV manufacturers make a great efforts to reduce production cost by using low-priced materials such as steels instead of aluminum and plastic etc. In this paper we have developed a new low-priced electrogalvanized steel sheet, which has a black resin composite layer, to substitute conventional high-priced PCM steel and plastic mold for rear cover panel in the digital TV. The black resin composite was prepared by mechanical dispersion of the mixture solution that consists of high solid polyester resin, melamine hardener, black pigment, micronized silica paste, polyacrylate texturing particle and miscellaneous additives. The composite solution was coated on the steel sheet using roll coater followed by induction furnace curing and cooling. Although the coated layer has a half thickness compared to the conventional PCM steels having $23{\mu}m$ thickness, it exhibits excellent quality for the usage of rear cover panel. The new steel sheet was applied to test products to get quality certification from worldwide electronic appliance customers. Detailed discussion provides in this paper including preparation of composite solution, roll coating technology, induction curing technology and quality evaluation from customers.

• 한국건축시공학회지
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• 제11권3호
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• pp.292-300
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• 2011

현재 국내 건설 산업은 고층화, 대형화 되어감에 따라 새로운 기술 개발로 비약적인 발전과 함께 품질향상을 위해 품질관리기법 및 품질관리제도 개선을 하고 있지만, 기술개발에 비해 건축물의 품질향상수준은 미흡한 수준이다. 반면에, 사용자의 의식변화로 건설품질에 대한 관심이 증가됨에 따라 요구품질수준이 높아지고 있다. 정부에서는 책임감리제도의 시행 및 해외업체의 국내 감리업무진출 허용 등의 품질제도를 강화하였고 및 민간부문에서도 사전자격심사제도의 시행 및 ISO 9000시리즈의 품질보증 등을 통한 품질 향상을 꾀하고 있지만, 현행 건설공사는 설계, 재료, 공법 등이 이미 확정된 발주자의 공사 시방서에 의한 공사를 수행함에 따라 정해진 사항의 이행 여부만을 판단할 뿐 수급자의 품질 개선을 위한 기술 개발의 필요성 및 기회를 제공하지 못하고 있다. 따라서 본 연구에서는 건설 공사단계에서 수급자가 자발적으로 품질확보를 할 수 있는 지불규정제도의 업무프로세스와 제도개선 방안을 제시하였다.

• KAPE누리
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• 통권102호
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• pp.10-13
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• 2005