• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.2
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• pp.71-82
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• 2006

This study was carried out to assess and analyze the overall problems of the facilities in recycling and treating of foodwaste on the basis of the unit operation facilities. It proposes effective alternatives for the high profitable management that can meet the regulation of the facilities. The study is composed of several parts including a collection of academic reports, field studies regarding the facilities operated by local government and the private sector, the analysis on odor samples from compost facilities and processing facilities for animal feed from foodwaste. Twenty facilities were surveyed on the field to find out the existing problems and to compare between facilities. Several facilities didn't meet the governmental regulation on some processes, especially the stages of input, storage, odor control and the qualities of final products under the unit equipment operation. The analysis on the odors from the phases of input, shredding and fermentation of a compost facility and processing facilities for feed, the odors from shredding equipments were higher in concentration than the others. The Major odors from the composting facility contained hydrogen sulfide ($H_2S$), methyl mercaptan ($CH_3{SH}$), Dimethyl sulfide ($(CH_3)_2S$) and Ammonia ($NH_3$) and the major odors from the animal feed facility contained methyl mercaptan ($CH_3{SH}$), Trimethylamine ($(CH_3)_3N$) and Acetaldehyde ($CH_3CHO$).

• 한국정보통신설비학회:학술대회논문집
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• 2003.08a
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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.

• Journal of Environmental Science International
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• v.30 no.3
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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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• v.12 no.1
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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.

• The Transactions of the Korean Institute of Power Electronics
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• v.17 no.1
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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.

• Journal of Environmental Impact Assessment
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• v.8 no.1
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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.

• Journal of Korean Society for Quality Management
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• v.38 no.2
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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.

• Journal of the Korea Organic Resources Recycling Association
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• v.23 no.3
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• pp.68-77
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• 2015

This study was conducted to characterize food waste leachate (FWL) and to compare its characteristics according to generation source: feed supplement- and compost-producing facilities. FWL contained high levels of organic compounds such as carbohydrate, protein and lipid. The moisture content of FWL was among the range of conventional wet anaerobic digestion. FWL was acidic (pH of $4.0{\pm}0.3$) and showed high coefficients of variance for specific parameters: carbohydrate, protein, lipid, ethanol, acetic acid and propionic acid. FWL derived from feed supplement-producing facilities showed slightly lower concentrations of most parameters than FWL derived from compost-producers. However, the difference was not significant at 5% significance level according to analysis of variance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.137-146
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• 2018

The purpose of this study was to derive and analyze the hub facilities that occupy major positions in the vehicle movement networks of livestock facilities. For this purpose, this study used the KAHIS data provided by Animal and Plant Quarantine Agency. The hub facilities were derived from the degree centrality & betweenness centrality. The analysis results are summarized as follows. First, in a livestock facility's vehicle movement network, there are a small number of hub facilities with very high centrality indicator values compared to other facilities. Second, the hub facilities based on the degree centrality are the feed factory, the milk collecting center, slaughterhouse, slaughterhouse for chicken, and livestock markets. Third, the hub facilities based on the betweenness centrality are the livestock markets, the feed factory, and slaughterhouse. Fourth, hub facilities based on the degree centrality are concentrated in a particular area, but the hub facilities based on betweenness centrality are distributed relatively evenly.

• Korean Journal of Poultry Science
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• v.45 no.1
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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.