• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.404-404
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• 2015

본 연구에서는 도시침수 저감을 위한 여러 구조적인 시설물 중에서도 빗물저류조의 펌프 적정 용량 산정에 관한 연구를 실시하였다. 대규모로 설치되어 자연 방류를 하는 온라인 빗물저류조와 달리 우수 관망 내 설치된 오프라인 빗물저류조의 경우 도심지에 위치하여 규모에 한계가 있으며 신설이나 증대 등에도 제한이 있다. 따라서 기존 빗물저류조 능력의 최대화가 필요하다. 현재 빗물저류조 펌프 운영시스템은 일정 수위 이상이거나 강우 종료 후 토출을 시작하므로 연속강우에 대한 대처가 취약하다. 연속강우에 대한 빗물저류조 능력의 최대화를 위해서는 기존 배제시간 검토가 필요하다. 이를 통하여 펌프 적정 용량을 산정함으로써 도시침수 저감이 가능하다. 본 연구에서는 대림3 어린이공원 빗물저류조를 대상으로 여러 기왕강우를 적용하여 도시침수를 저감할 수 있는 펌프의 적정 용량을 산정한다.

• Membrane and Water Treatment
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• v.10 no.1
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• pp.83-89
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• 2019

The most common way of reducing non-point source pollutants from agricultural areas is the installation of reservoirs. However, this method is only effective for surface runoff of settleable pollutants. This study was conducted to estimate the effect of interflow, baseflow, and surface runoff on pollutant runoff in a small agricultural catchment. Runoff of organic matters, SS, and T-P were directly proportional to the rainfall variation, while ammonia and nitrate were inversely proportional to the amount of rainfall. The interflow and baseflow was only 46% of the total stream flow, but the nitrate load reached 78%. The interflow as a nutrient transport pathway should be considered for managing a stream water quality. It requires careful attention and appropriate control methodology such as vegetation to consider the influence by interflow. The reservoir as a dry extended detention pond (DEDP) has function of nutrient captor.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.111-112
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• 2022

Lightweight aggregate is a porous material that has a lower density than natural aggregate and is a lightweight construction material. Lightweight Aggregate has a suitable purpose because it is effective in reducing the heavy unit mass in high-rise buildings. However, since lightweight aggregate has weak strength and high water absorption compared to natural aggregate, it is difficult to control the quality of concrete. Although lightweight aggregate has disadvantages such as high water absorption, it is expected that the demand for lightweight aggregate concrete will continue to use in the future because the advantage of being able to reduce the weight of concrete is greater. In this study, we conducted an experimantal study on the compressive strength property of cement matrix according to the type of lightweight aggregate.

• Proceedings of the Korean Society of Computer Information Conference
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• 2022.07a
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• pp.107-109
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• 2022

본 논문은 건설구조물 안전의 가장 중요한 요소 중 하나인 콘크리트 압축강도 안정성을 확보하기 위한 시스템으로, 콘크리트 구조물을 만들 재료인 레미콘의 수분 감소율에 따른 압축강도 감소 리스크를 관리할 수 있는 모델을 제시하였다. 동일한 물,시멘트비(W/C)로 생산된 레미콘은 현장타설시까지 교통환경으로 인한 도착시간 지연 및 강우, 강설 등 외부적인 요건으로 감수율이 발생하는 리스크가 발생한다. 이로 인해 콘크리트의 압축강도가 저감하는 중대한 문제가 발생한다. 본 연구에서 제시한 알고리즘을 이용하여 현장 타설전 콘크리트 시료의 함수율을 측정하여 감수율이 발생한 제품 발견시, 실시간으로 Operator로 GCM 기반의 Push Alarm을 전송하여 감수율이 반영된 제품을 제공함으로써 구조물의 안전성을 확보할 수 있는 시스템을 모델링하였다. 본 연구는 기존시스템의 문제점을 실시간으로 개선할 수 있는 것으로 건설현장의 구조물 안정성 확보에 효과가 클 것으로 기대된다.

• Archives of Metallurgy and Materials
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• v.66 no.3
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• pp.745-750
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• 2021

A novel process to recover lithium and manganese oxides from a cathode material (LiMn₂O₄) of spent lithium-ion battery was attempted using thermal reaction with hydrogen gas at elevated temperatures. A hydrogen gas as a reducing agent was used with LiMn₂O₄ powder and it was found that separation of Li₂O and MnO was taken place at 1050℃. The powder after thermal process was washed away with distilled water and only lithium was dissolved in the water and manganese oxide powder left behind. It was noted that manganese oxide powder was found to be 98.20 wt.% and the lithium content in the solution was 1,928 ppm, respectively.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.6
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• pp.601-607
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• 2003

This study was attempted to investigate the physicochemical changes during soybean-leaf water kimchis fermentation by adding wheat flour in cooking water. Soybean-leaf water kimchis with five different levels of wheat flour in cooking water(0%;A, 5%;B 10%;c, 15%;D, 20%;E) were tested for rhological parameters, fine structural changes, sensory evaluations and chemical analysis. The composition of the soybean-leaf was moisture (80.9%), protein(6.8%), fat(0.6%), ash(2.1%) and alkalinity (+14.9). The amount of reducing sugars of sample A and other samples were 0.75% and 1.08∼1.4% in the initial fermentation stage, but decreased to 0.3 and 0.43∼0.50% in the later fermentation stage, respectively. The pH of sample A decreased from 5.17 to 4.72 during the initial fermentation. On sample B, C, D and E, pH's decreased rapidly during the initial fermentation, but they did not change much in the later fermentation stage. The pectin contents of all samples decreased during 2nd and 4th day of fermentation, then the change was slow. The amount of hemicellulose. cellulose and lignin in terms of the DNF and ADF were varied from 4 to 33%, but the contents of them did not greatly changed during the fermentation. The sensory evaluation showed that both B and C samples had the good score in sweety taste, roasted nutty taste, and the ease of swallowing measured as chewiness. From these results, the optimum soybean-leaf water kimchis can be prepared when 200g soybean-leaf, 1000$m\ell$ water, 15g garlic, 3% red pepper powder and 5 ∼0% wheat flour were fermented at 20$^{\circ}C$ for 2 days.

• International Journal of Quality Innovation
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• v.6 no.3
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• pp.173-189
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• 2005

A life-cycle assessment (LCA) is based on the attention given to the environmental protection and concerning the possible impact while producing, making, and consuming products. It includes all environmental concerns and the potential impact of a product's life cycle from raw material procurement, manufacturing, usage, and disposal (that is, from cradle to grave). This study assesses the environmental impact of the ultra pure water process of semiconductor manufacturing by a life-cycle assessment in order to point out the heavy environmental impact process for industry when attempting a balanced point between production and environmental protection. The main purpose of this research is studying the development and application of this technology by setting the ultra pure water of semiconductor manufacturing as a target. We evaluate the environmental impact of the Precoat filter process and the Cation/Anion (C/A) filter process of an ultra pure water manufacturing process. The difference is filter material used produces different water quality and waste material, and has a significant, different environmental influence. Finally, we calculate the cost by engineering economics so as to analyze deeply the minimized environmental impact and suitable process that can be accepted by industry. The structure of this study is mainly combined with a life-cycle assessment by implementing analysis software, using SimaPro as a tool. We clearly understand the environmental impact of ultra pure water of semiconductor used and provide a promotion alternative to the heavy environmental impact items by calculating the environmental impact during a life cycle. At the same time, we specify the cost of reducing the environmental impact by a life-cycle cost analysis.

• Korean journal of food and cookery science
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• v.3 no.2
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• pp.28-37
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• 1987

The changes of various cooking experiment (gelatinization, swelling, texture, water absorbance) and amino acid, fatty acid composition and the effect of digestibility on glucose examination (in vitro) were investigated at various rice during cooking by using milk. The results are summarized as follows. 1) In the effect of various water-to-rice ratios on the degree of absorbance of rice, Rice (using water) always showed higher absorbance than rice. (using milk) optimum water absorbance time were shown to be 40 minute for rice (using water) and 50 minute for rice (using milk). 2) The degree of gelatinization (D.G) by iodine colorimetric method increased proportionally according to the increase of water-to-rice ratio and rice cooking always showed higher D.G than rice milk cooking. When the same D.G rice milk cooking food required 40~50% higher water-to-rice ratios than rice cooking food. 3) Various rice cooking food, the palatability were best food by rice bean milk cooking food. 4) The main Amino acid composition of using milk rice cooked food were Glutenine, Leusine, Asparagine, Valine, Arginin above 42% of the Total Amino acid. The contents of Lysine and Methionine were 476.50mg, 412.16mg in using Milk rice cooking food. 5) Using rice Milk cooking food ana Rice bean Milk cooking food, rice cooking, rice bean cooking in phosphate Buffer, in vitro Enzymatic glucose were carried out in dialysis bag. During 90 minute of incubation at $37^{\circ}C$, reducing sugar were analyzed from dialysate. Starch digestibility measured from human Saliva, Sali a, Pencreatic Amylase treatment was high in Rice Milk cooking food, Rice bean Milk cooking food and rice cooking food and rice bean cooking food but remarkely low.

• Environmental and Resource Economics Review
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• v.21 no.1
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• pp.129-156
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• 2012

This study analyzes the contribution to the national economy of the stable water supply through managing multi-purpose dam. For the analysis, we consider 17 major multi-purpose dams and build a CGE model with summer water and winter water being the production factors as the base year of 2007. We analyze the economic impact of meeting water demand due to the dam management and estimate the risk premium of reducing the uncertainty of water supply. The analysis results show a significant production decrease in the industries of agriculture, forestry and fisheries and tap water as well as the food and beverage industry using the former industries' output as intermediates in the production and show an production increase largely in steel industry and electronic and electrical industries. Being compared to the benchmark solution, GNP is analyzed as being reduced by 0.22~0.68%. Meanwhile, the risk premium is estimated to be about 4 billion to 24 billion won for the value 01 the measure of relative risk aversion in the range 01 0.5 to 3.0.

• Food Quality and Culture
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• v.2 no.1
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• pp.55-60
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• 2008

This study examined the effects of lactic acid spray, hot water spray, or their combined treatment, as well as the effects of acidified sodium chlorite (ASC), for the decontamination of Escherichia coli on beef carcass surfaces using a commercial intervention system. With this system, the effects of 2 or 4% lactic acid (v/v), hot water ($89{\pm}1^{\circ}C$), or their combined treatment, were examined in terms of reducing inoculated E. coli. ASC (266 ppm), which was adjusted to pH 2.5 using acetic acid or citric acid, was applied using a hand-held spray system. When the beef carcasses were treated with 2 or 4% lactic acid for 10.4 s, less than 1 log reductions of inoculated E. coli were observed. A hot water spray treatment for 9.8 s resulted in a 2.1 log reduction of inoculated E. coli. However, when the hot water was followed with either 2 or 4% lactic acid, no difference in E. coli reduction was found between the hot water alone or the combined treatment with lactic acid. When ASC was adjusted to pH 2.5 with acetic acid and citric acid, 3.8 and 4.1 log reductions of E. coli were observed, respectively. Overall, the lactic acid spray treatment was least effective, and the ASC treatment was most effective, for the E. coli decontamination of beef carcasses. Therefore, these data suggest that ASC would be a more effective intervention against E. coli than most of the methods currently being used. However, more research is required to evaluate the effects of ASC on other organisms, as well as to identify application methods that will not affect meat quality.