• 유기물자원화
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• 제14권2호
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• pp.71-82
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• 2006

본 연구에서는 음식물류폐기물처리시설의 시설운영에 대한 전반적인 문제점 분석을 통해 음식물류폐기물처리시설의 효율적인 운영관리방안을 제시하고자 음식물류폐기물 관련 연구보고서와 자료를 수집 분석하였다. 음식물류폐기물처리시설에서 발생하는 악취의 특성을 알아보기 위하여 퇴비화시설과 사료화시설의 악취시료를 채취하여 분석하였다. 퇴비화 및 사료화시설의 주요 악취발생인이 큰 투입공정, 파쇄공정, 발효공정에 대하여 악취를 측정 분석한 결과 파쇄공정이 악취농도가 가장 높았다. 퇴비화시설의 주요 악취성분은 황화수소, 메틸머캅탄, 다이메틸설파이드, 암모니아였으며, 사료화시설의 주요 악취성분은 메틸머캅탄, 트라이메틸아민, 아세트알데하이드이었다.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2003년도 하계학술대회
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• pp.172-174
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• 2003

In this paper, we analyze the traveling-wave electro-absorption modulator (TW-EAM) in consideration of the microwave feed-line. The TW-EAM is analyzed by using the equivalent circuit model. The microwave feed-line isanalyzed by momentum method. In a view point of microwave characteristics, we present the effect of the structure and the length of microwave feed-line.

• 한국환경과학회지
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• 제30권3호
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• pp.289-293
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• 2021

This study was conducted to investigate the distribution of duck production in duck housing as a function of the breeding period. The items in duck production distribution included body weight, feed intake, feed conversion ratio, and average duck production. All data were based on eight cycles (June and December, 2017; February, June, August, September, and November, 2018; February, 2019) at Farm Site 1 through 7. The most optimal results in the duck production distribution were observed at Site 1 for weight gain, feed intake, and feed efficiency. This could be explained by the fact that Site 1 was well managed in environmental improvement and sustainability. Based on these data, selective alternatives to improve duck production in duck farms are recommended as follows: first, proper management and recording of litter used as a flooring material are required, and second, continuous management such as temperature, relative humidity and ventilation is needed. Lastly, it is necessary to change duck facilities by introducing environmental management techniques. Furthermore, efforts to improve the overall facilities and management of duck breeding farms through additional field studies are needed in the future.

• Journal of Power Electronics
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• 제12권1호
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• pp.157-163
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• 2012

Internet Data Centers (IDCs), which are essential facilities in the modern IT industry, typically have scores of MW of concentrated electric loads. The provision of an Uninterruptible Power Supply (UPS) is necessary for the power feed system of IDCs owing to the need for stable power. Thus, conventional IDC AC power feed systems have three cascaded power conversion stages, (AC-DC), (DC-AC), and (AC-DC), resulting in a very low conversion efficiency. In comparison, DC power feed systems require only a single power conversion stage (AC-DC) to supply AC main power to DC server loads, resulting in comparatively high conversion efficiency and reliability [4-11]. This paper compares the efficiencies of a 220V AC power feed system with those of a 300V DC power feed system under equal load conditions, as established by the Mok-Dong IDC of Korea Telecom Co. Ltd. (KT). Experimental results show that the total operation efficiency of the 300V DC power feed system is approximately 15% higher than that of the 220V AC power feed system.

• 전력전자학회논문지
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• 제17권1호
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• pp.27-33
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• 2012

Internet Data Centers (IDC), as essential facilities for modern IT industry, typically have scores of MW of concentrated electric loads. Uninterruptible Power Supplies (UPS) are necessary for the power feed system of IDCs because of stable power requirement. Thus, conventional AC power feed systems of IDCs have three cascaded power conversion stages such as (AC-DC), (DC-AC), and (AC-DC), which results in very low conversion efficiency. On the contrary, DC power feed systems need just a single power conversion stage (AC-DC) supplying AC mains power to DC server loads, which gives comparatively high conversion efficiency and reliability. This paper compares the efficiencies between 220V AC power feed system and 300V DC power feed system on equal load conditions which were established in Mok-Dong IDC of Korea Telecom company (KT). Experimental results show that the total operation efficiency of the 300V DC power feed system is around 15% higher than that of the 220V AC power feed system.

• 환경영향평가
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• 제8권1호
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• pp.133-139
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• 1999

Community residents are tend to evade waste treatment facilities such as waste landfills, waste incinerators. Therefore, decision-makers of waste management are concerned about the reduction and recycling of food garbage. As a treatment alternative of food garbage which consists of 30% of municipal waste, producing compost and feed stuff from food garbage is environmentally amenable. In considering the characteristics of food garbage are putrid and high moisturized, methods of landfilling and incineration for food garbage are environmentally inadequate. For the institutionalization of food garbage recycling, separate discharge, establishment of collection system, securing of market for compost and feed stuff manufactured from food garbage, and tax and financial incentives for food garbage recycling facilities are necessary.

• 품질경영학회지
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• 제38권2호
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• pp.212-224
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• 2010

After the introduction of Volume-based Waste Fee System for municipal wastes, the disposal of food wastes became an issue in society. As this reason, recycling food wastes facilities play an important role such as converting of food waste into animal feed or composting of food waste. Therefore, there is need of efficiency measurement of the facilities to reduce the inefficiency of factors. The purpose of this paper is to make a reasonable suggestion for the improvement of inefficient recycling food wastes facilities. This paper assesses the relative efficiency of recycling food wastes facilities by examining the relationship between inputs and outputs in 41 facilities using data envelopment analysis(DEA). The result shows that 4 facilities whose values of CCR efficiency are 1, and 10 facilities whose values of BCC efficiency are 1, RTS indicates IRS of 17 facilities and CRS of 6 facilities.

• 유기물자원화
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• 제23권3호
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• pp.68-77
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• 2015

본 연구에서는 수도권매립지 반입 음폐수에 대한 성상분석을 통하여 음폐수의 일반적인 특성을 살펴보고, 음폐수 유래 공정(사료화, 퇴비화)에 따른 음폐수 성상 특징을 비교하였다. 음폐수는 고농도의 유기물을 함유한 폐수이며 습식 혐기소화가 가능한 범위의 함수율을 나타내었다. 음폐수는 산성을 띠며 비교적 높은 세부 성상(탄수화물, 단백질, 지방, 에탄올, 아세트산, 프로피온산 등)의 변화율을 나타냈다. 사료화 및 퇴비화 공정 유래 음폐수 성상을 비교한 결과, 평균값 기준으로 사료화가 다소 낮은 농도를 보였으나 분산분석에 따른 통계적 차이는 유의성이 없었다.

• 한국산학기술학회논문지
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• 제19권6호
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• pp.137-146
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• 2018

축산시설 사이의 차량이동은 국내에서 가축전염병 확산의 주요 원인이다. 이 같은 상황에서 본 연구는 축산시설의 차량이동 네트워크에서 주요한 위치를 차지하는 허브시설을 도출하고, 그 특성을 분석하는 것을 목적으로 한다. 이를 위하여 본 연구는 농림축산검역본부의 KAHIS(Korea Animal Health Intergrated System)에서 제공하는 축산시설의 차량 진출입자료를 활용하였다. 허브시설의 도출에는 사회연결망 분석의 대표적인 중심성 지표인 연결정도 중심성과 매개 중심성 지표를 활용하였다. 본 연구의 분석결과를 요약하면 다음과 같다. 첫째, 축산시설의 차량이동 네트워크에는 다른 시설에 비하여 매우 높은 중심성 지표 값을 가지는 소수의 허브 시설이 존재한다. 둘째, 연결정도 중심성 기준의 허브시설은 사료공장, 집유장, 도축장, 도계장, 가축시장이다. 셋째, 매개 중심성 기준의 허브시설은 가축시장, 사료공장, 도축장이다. 넷째. 연결정도 중심성에 기반한 허브시설은 특정지역에 집중되어 입지하고 있으나, 매개 중심성에 따른 허브시설을 상대적으로 고르게 분포하고 있다. 다섯째, 중심성 지표에 따른 허브시설은 시간이 지나도 상당히 안정적으로 유지된다. 본 연구는 축산시설 사이의 차량 이동이 가축 전염병 전파의 주요 원인으로 지목되는 상황에서, 방대한 진출입 자료를 활용하여, 허브시설을 도출하였다는 점에서 그 의의가 있다.

• 한국가금학회지
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• 제45권1호
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• pp.1-15
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• 2018

Salmonella infections in livestock industry cause various problems such as worsening animal welfare and productivity, damaging consumer confidence in the food safety of animal products. Chicken meat and eggs are known as major source of pathogen causing human foodborne infections. Therefore food safety concerns have prompted the poultry producers and governments to introduce the strategy and regulation to control these pathogens. Salmonella can persist for long periods of time in a wide range of spaces including feed bin, feed processing facilities, poultry farm, slaughterhouse, processing plants, etc. For the effective and constant Salmonella control, combination of pre-harvest, harvest and post-harvest measures should be considered comprehensively. The control measures would be most effective at farm level where the contamination initiates. Transmission of pathogen from feed origin to the live poultry and finally to the products was proven already. To control bacteria in the feed ingredients and formula feed, thermal processing, irradiation or chemical treatment may be applied. Chemical treatments to inhibit Salmonella in the feed involve the use of products containing organic acids, formaldehyde, or a combination of such compounds. However, recontamination which might occur during storage and transport process and/or by other various factors should always be under control and eliminated. Feed additives used to control Salmonella in birds' gastrointestinal track can be of various types, including prebiotics, probiotics, organic acids and bacteriophages. Although their mode of action varies, they ultimately inhibit the colonization of Salmonella in the gut and improve the performance of birds. This review describes the strategies that could be adapted to the management of feedstuffs and the use of feed additives in pre-harvest stage to control Salmonella contamination in poultry farming.