• 한국농공학회지
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• 제26권3호
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• pp.46-58
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• 1984

This study was carried out to investigate the compressive strength and the other effects varying to seasons and curing days on the wet curing conditions of the plain concrete. The results obtained are summarized as follows; 1. The longer the wet curing days and the higher the temperature, the greater the compressive strength was expected. 2.。$_2$8, compressive strength of concrete at 28 days under the dry curing conditions showed a range in 64-76% of that under the wet curing conditions. 3. The seasonal variations in the compressive strength under the wet curing showed in order of summer>spring=autumn>winter, and that under the dry curing were in order of spring ≒autumn> summer> winter. 4. In order to obtain 90% of the design compressive strength, 7 days in spring or autumn and 2 weeks of the wet curing in summer were required. 5. The compressive strength of concrete under the wet curing by using wet straw bag cover was almost the same as that of water curing method. 6. Under the wet curing conditions, the higher the temperature, the greater the effect of the curing of concrete was obtained, however, the compressive strength of concrete was decreased under relatively higher (over 15$^{\circ}$ C) and lower temperature (below 4$^{\circ}$C). 7. Freezing damage was occured when temperature was below 0$^{\circ}$ C and humidity was relatively high. 8. A considerable differnce between estimation of $^{\circ}$$_2$8 from $^{\circ}$7 and measured one was appeared in case of the dry curing conditions. Oregon formula was appeared to be acceptable under the wet curing conditions. 9. In relationship between $^{\circ}$$_2$8 and $^{\circ}$7~, $^{\circ}$28=1. 52 $^{\circ}$7 under the wet curing conditions except winter season, and $^{\circ}$$_2$8 =(1.39-1, 48)$^{\circ}$7 under the dry curing conditions were shown.

• Asian-Australasian Journal of Animal Sciences
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• 제29권2호
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• pp.241-249
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• 2016

The supplementation of livestock feed with animal protein is a present cause for public concern, and plant protein shortages have become increasingly prominent in China. This conflict may be resolved by fully utilizing currently available sources of plant protein. We estimated the rumen degradability and the small intestinal digestibility of the amino acids (AA) in rapeseed meal (RSM), soybean meal (SBM), sunflower seed meal (SFM) and sesame meal (SSM) using the mobile nylon bag method to determine the absorbable AA content of these protein supplements as a guide towards dietary formulations for the dairy industry. Overall, this study aimed to utilize protein supplements effectively to guide dietary formulations to increase milk yield and save plant protein resources. To this end, we studied four cows with a permanent rumen fistula and duodenal T-shape fistula in a $4{\times}4$ Latin square experimental design. The results showed that the total small intestine absorbable amino acids and small intestine absorbable essential amino acids were higher in the SBM (26.34% and 13.11% dry matter [DM], respectively) than in the SFM (13.97% and 6.89% DM, respectively). The small intestine absorbable Lys contents of the SFM, SSM, RSM and SBM were 0.86%, 0.88%, 1.43%, and 2.12% (DM basis), respectively, and the absorbable Met contents of these meals were 0.28%, 1.03%, 0.52%, and 0.47% (DM basis), respectively. Among the examined food sources, the milk protein score of the SBM (0.181) was highest followed by those of the RSM (0.136), SSM (0.108) and SFM (0.106). The absorbable amino acid contents of the protein supplements accurately reflected protein availability, which is an important indicator of the balance of feed formulation. Therefore, a database detailing the absorbable AA should be established.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2012년도 춘계학술논문집 1부
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• pp.367-370
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• 2012

본 연구는 하나의 장치 내에서 "싸이클론-관성충돌-여과포 집진"이라는 다단 제진 단계가 동시에 이루어져 입경 분포별로 순차적인 제진이 가능한 멀티 집진기의 처리가스 제어 효율을 극대화시킬 수 있는 기류 흐름을 얻기 위한 최적화 설계 조건을 검토하는 것이다. 우선 1단계 제진 과정인 원심력을 이용하여 조대입자의 유선 이탈을 촉진시킬 수 있는 사이클론 유동을 최적화시키기 위한 집진기 입구 형상 설계 검토를 위해 수치 해석적 연구를 수행하였다. 그 결과, 멀티집진기 입구 형상을 일반적인 설계 방식인 접선 유입식으로만 설계한 것에 비해 선회류를 한번 더 가속화시킬 수 있는 가이드 베인을 추가로 설계한 경우 선회류의 pitch가 짧고 강하게 형성되어 사이클론부에서 조대입자의 유선 이탈을 촉진시키는데 매우 효과적인 것으로 예측되었다. 단, 사이클론부 하단 벤츄리 형상으로 인해 약 4~5 m/s의 강한 하향 흐름이 호퍼 하단까지 형성되고 있어 탈리 분진의 재비산 문제가 발생할 가능성이 크므로 벤츄리 형상 설치 유무에 대한 영향도 추가적으로 연구가 필요할 것으로 판단된다.

• 복식
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• 제60권2호
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• pp.68-80
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• 2010

In order to get the information needed for the preservation and application of Korean traditional dyeing techniques to modern textiles products, the present study analyzed the color and color differences of dyed goods according to the contents of fabrics and the traditional techniques of dyeing the Buddhist priests' robes. A spectrophotometer was used to measure the differences in achromatic color according to dyeing techniques, dyestuff, kinds of dyed fabrics, and after-treatment methods. Through experiments based on the traditional dyeing techniques used by Korean Buddhist priests, a total of 144 pieces of dyed fabrics were made and all the colors of those 144 pieces were analyzed. Among three dyeing techniques tested; (1) dyeing with a dye-bath made of ink stick that was ground down with water, (2) dyeing with a dye-bath made by shaking a bag containing ink powder in water, and (3) dyeing with a dye-bath made by rubbing a boiled ink stick on a fabric, dyeing with a dye-bath made of ink stick that was ground down with water was shown to be the best technique in terms of coloring. For fabrics, ramie was the best of all three techniques in terms of making achromatic color. Starching and rubbing was the most effective after-treatment method used on both fabrics dyed with a grounded ink stick and on fabrics dyed by rubbing a boiled ink stick on them. As a whole, yangyeonmook, made from minerals' soot, is better than songyeonmook, which is made by burning old pine trees or yooyeonmook, which is made by burning oils from seeds. Therefore, yangyeonmook could help to preserve and utilize the traditional dyeing techniques of Korea in a practical way in modern life.

• Asian-Australasian Journal of Animal Sciences
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• 제13권3호
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• pp.313-316
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• 2000

Three Holstein steers, fitted with ruminal and duodenal cannulas, were used in a replicated $3{\times}3$ Latin square design to determine the digestibility of dietary nitrogen in total digestive tract by three methods, 1) mobile nylon bag (MNB); 2) total fecal collection (TFC); and 3) washed fecal sample after freezing and thawing through a sieve with a pore size of $45{\mu}m$ (WFS). A basal diet of oaten hay-barley was supplemented with one of the following protein sources; soybean meal, fish meal or blood meal. Steers were fed at a level of 2% of body weight. The experimental diets were contained approximately 1.85% nitrogen. There were no differences (p>0.05) among the diets on DM, NDF and nitrogen disappearances, and the diet results were pooled to assess the methods. Total tract disappearances of dry matter and neutral detergent fiber were 61.6, 71.1 and 78.9 and 25.3, 63.2 and 64.6 for MNB, TFC and WFS methods, respectively. The lower digestibility of DM and NDF in the MNB method could be a result of low ruminal incubation time. The TFC method had the lower (p<0.05) determination of nitrogen disappearance in the total digestive tract than the MNB and WFS methods. On the other hand, nitrogen disappearance in the total digestive tract determined by the WFS technique was comparable to that in MNB technique, as there was no significant difference (p>0.05) between the methods. It is shown that the disappearance of dietary nitrogen in the total digestive tract could be estimated in the intact animals by using washed fecal sample prior to freezing and thawing.

• Asian-Australasian Journal of Animal Sciences
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• 제6권1호
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• pp.5-11
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• 1993

First crop of alfalfa (Medicago sativa L.) was harvested, wilted and ensiled with or without NaOH or $NH_3$, and fed to three rumen fistulated goats in a $3{\times}3$ Latin-square design. Each alkali treatment (2.44% of alfalfa dry matter) was made by spraying its solution prior to ensiling. Silage pH, $NH_3-N$ and butyric acid concentration were increased with each alkali addition, and NaOH-treated silage showed the lowest chemical quality. Compared with untreated silage, digestibilities of organic matter, ADF and cellulose were depressed by both alkali treatments, and the reductions in NaOH-treated silage were significant. Crude protein digestibility was also significantly decreased in NaOH-treated silage, but the goats receiving the silage excreted less nitrogen in urine than those on the other two silages. Nitrogen retention of goats was not different among the treatments. Ruminal solubility and potential degradability of dry matter and nitrogen determined with the in situ bag technique were reduced, and rate of degradation of the two components were increased by the NaOH treatment. Addition of $NH_3$ provided ruminal soluble nitrogen to the silage, but the rate of degradation was similar to that of untreated silage. These results suggest that NaOH treatment would denature the protein and reduce the susceptibility to microbial degradation in the rumen, while no positive effect of alkali treatment on fiber digestion and nitrogen utilization was observed in this study.

• Asian-Australasian Journal of Animal Sciences
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• 제19권2호
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• pp.181-188
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• 2006

The objective of this research was to determine the effects of synchronizing the rate of dietary energy and nitrogen release on: ruminal fermentation, microbial protein synthesis, blood urea nitrogen, and nutrient digestibility in beef cattle. Four, two-and-a-half year old Brahman-Thai native crossbred steers were selected for the project. Each steer was fitted with a rumen cannula and proximal duodenal cannula. The steers were then randomly assigned in a $4{\times}4$ Latin square design to receive four dietary treatments. Prior to formulation of the dietary treatments, feed ingredients were analyzed for chemical composition and a nylon bag technique was used to analyze the treatments various ingredients for degradability. The treatments were organized in four levels of a synchrony index (0.39, 0.50, 0.62 and 0.74). The results showed that dry matter digestibility trend to be increased (p<0.06), organic matter and acid detergent fiber digestibility increased linearly (p<0.05), while crude protein and neutral detergent fiber digestibility were not significantly different (p>0.05). Higher concentration and fluctuation of ruminal ammonia and blood urea were observed in the animal that received the lower synchrony index diets. As the levels of the synchrony index increased, the concentrations of ruminal ammonia nitrogen and blood urea nitrogen, at the 4 h post feeding, decreased linearly (p<0.05). Total volatile fatty acid and bacteria populations at the 4 h post feeding increased linearly (p<0.05). Microbial protein synthesis trend to be increase (p<0.08). The results of this research indicate that synchronizing the rate of degradation of dietary energy and nitrogen release improves ruminal fermentation, microbial protein synthesis and feed utilization.

• 환경위생공학
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• 제12권3호
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• pp.41-49
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• 1997

In South Korea since 1970s the rapid development of economic growth has brought about "Urbanization" in many areas and also raised the level of people's life in many ways. At the same time, however, the industrialization and overpopulated districts in many areas have caused the problems of air pollution in necessary. Among those air pollution, in particular, in large cities has become more serious since 1990s than before. Air pollution, like TSP and SO$_{x}$ caused by heating, generation of electric power and industrialization in 1980s, showed as that of the type of an underdeveloping country and was not hazardous enough to people in the least. Unfortunately, in 1990s NO$_{x}$, CO and O$_{3}$ caused by the soaring numbers of many types of cars have exhausted air pollutant more hazardous as the same air pollution type of many developed countries. So, the purpose of this study would be to analyze the changes of concentration of NO$_{x}$ and CO on environmental air by traffic volume and from the side drive way to the degree of distance in Sungnam City, and recognize the citizens' consciousness to air pollution and suggest the best walking point in part, and plan to design the reasonable use of cars and finally make the air quality improve toward the better-ment in part. From the research result we can know that people walking in the street would be protected from the hazardous air pollutant caused by the cats if they walk apart from a drive way as far as they can in the street. Accordingly, it might, to minimize th affect of air pollution, be thought to be desirable that the consideration of in introduction the system that the vehicle using the diesel engine motor should use the centered-lane aparted from road. Another to be desirable is that along side the road, the trees inhaled the pollution should be planted.

• 한국기록관리학회지
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• 제18권2호
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• pp.163-188
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• 2018

차세대 기록관리시스템은 어떻게 만들어야 할까? 급변하는 시스템 개발 환경하에 공공기관의 기록관리시스템은 지난 10여 년간 답보 상태로 머물러 있었다. 이런 이유에는 사용자 요구사항 수용, 기록관리 신기술 적용을 하기 어렵게 만들어진 기록관리시스템 구조적 문제가 핵심 원인이라고 본다. 본 연구의 목적은 전자기록관리 현황 분석을 통한 차세대 기록관리시스템 재설계 모형을 제시하는 것에 있다. 본 연구의 선행연구격인 '차세대 전자기록관리 프로세스 재설계 연구(주현미, 임진희, 2017)' 결과와 선진 기록관리시스템의 기록관리 기술과 해외 시스템 사례를 분석하였다. 분석결과를 바탕으로 기록관리시스템 개선방향을 기능적 측면, 소프트웨어 설계 측면, 소프트웨어 배포 측면으로 분석하였고, 이 결과를 기록관리기관 유형에 적용하였다. 본 연구를 통해 마이크로서비스 아키텍처(MSA) 기반, 오픈소스 소프트웨어(OSS) 지향의 기록관리시스템을 만드는 것이 차세대 기록관리의 지향점이라고 제안한다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.279-284
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• 2009

Traditionally, so-called "industrial waste gases", such ad exhaust from boilers at industrial installations and a large quantity of soot discharged from power station, before their release into the atmosphere, have been on occasion subjected to an air cleaning process to remove fine particles that may pollute the atmosphere (such as mist and dust containing various powdery or oily substances and moisture from industrial waste gases). The release of industrial waste gases containing these particles directly into the atmosphere poses a serious threat to the earth environment; and recovery of these noxious substances is required by law in some countries and local governments. in urban areas, air pollution from automobile exhaust and others creates a serious condition. Some homes are equipped with and use indoor air purifiers. In many of the kitchens of restaurants, smoke generated during cooking and otherwise contaminated air are cleansed by air purifiers before being released outside or recycled inside. For the dust collecting devices to recover the fine particles contained in contaminated air, the cause for air pollution and how to purify air, many types based on various principles are known. Specifically, classified based on theories of particle collection, filtration, gravity, inertia, centrifugation, electricity, and cleaning types are cited as available processes. Among them, an appropriate type is selected according to the size or type of fine particles to be collected and conditions for installation. For the efficiency of dust collection, a filtration system (by using bag filters and others) and electric system are particularly outstanding and are therefore used widely in various areas of industry. In this research, rotary type high performance oil mist and smoke collecting system with self auto cleaning device equipped with the cleaning fluid spraying section is investigated.