• Animal Bioscience
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• 제34권4호
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• pp.567-574
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• 2021

Objective: In this study we investigated the effect of seasonal thermal stress on milk production and milk compositions between Holstein and Jersey dairy cows under the temperate-climate in Korea. Methods: A total of 9 Holstein lactating dairy cows (2.0±0.11 parity) which had a daily milk yield of 29.77±0.45 kg, and days in milk of 111.2±10.29 were selected similarly at the beginning of the experiments in each season. Also, a total of 9 Jersey lactating dairy cows (1.7±0.12 parity) which had a daily milk yield of 20.01±0.43 kg, and days in milk of 114.0±9.74 were selected similarly at the beginning of the experiments. Results: Results showed that the average ambient temperature (℃) and temperature-humidity index (THI) were higher in summer, and were lower in winter (p<0.05). The average relative humidity (RH, %) was higher in autumn than that of other seasons (p<0.05). Milk production was significantly decreased (Holstein 29.02 kg/d and Jersey 19.75 kg/d) in autumn than in other seasons (Holstein 30.14 kg/d and Jersey 20.96 kg/d). However, the milk production was negatively correlated in Holstein cows, and positively correlated in Jersey cows with THI values increased from 16 to 80. In addition, milk yield was increased by 15% in Holstein cows and decreased by 11% in Jersey cows with the THI values increased from 16 to 20. The fat and protein content percentage was significantly higher in Jersey milk than in Holstein milk, furthermore the fat and protein content yield was higher in Jersey cow milk than that of Holstein cow's milk with all THIs. Conclusion: From the study results, we concluded that Jersey cows might be less adaptable to low temperature of the winter, and this would have a negative impact on dairy farmer income since Korea's milk price estimation system places a higher value on milk yield than on milk compositions or sanitary grades.

• Asian-Australasian Journal of Animal Sciences
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• 제23권1호
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• pp.131-148
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• 2010

Piglet health at weaning is compromised due to several stress factors. Following the ban of antibiotic growth promoters new alternatives are required to control these problems. This paper reviews the evidence available for the use of spray dried animal plasma (SDAP) as an alternative to antibiotics in weaning pigs. Data from 75 trials in 43 publications involving over 12,000 piglets (mean values) have been used to calculate the performance responses of piglets according to several factors including SDAP origin, protein source from the control diet being replaced, dose of inclusion, age and weight of the piglets at weaning, sanitary conditions and simultaneous use or not of medication. Although the use of SDAP of all origins results in positive responses, it appears that plasma from porcine origin has the highest efficacy. This could be explained by the specificity of its IgG against porcine pathogens. During the first week post-weaning the response to plasma appears to increase with the inclusion dose, although over the two-week pre-starter period an optimal inclusion level of 4-8% is suggested. SDAP improves feed efficiency more markedly when the piglets are challenged with an experimental infection or when feed does not contain medication, which could be indicative of a lower expenditure of energy and nutrients to build an immune response against the challenge. There is evidence supporting that SDAP IgG and other bioactive substances therein prevent the binding of pathogens to the gut wall and reduce the incidence of diarrhoea in the post-weaning phase. Overall, plasma can be postulated as an excellent alternative to in-feed antimicrobials for piglets in the post-weaning phase.

• 한국식생활문화학회지
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• 제2권2호
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• pp.163-167
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• 1987

서울시와 경인지역을 중심으로 도시락 생산업체 16개사를 선정하여 방문 조사한 기기류 보유 현황은 다음과 같다. 1. 조리기기는 주로 레인지, 튀김기, 국솥, 밥솥을 사용하고 있었다. 2. 전처리기기는 푸드 캇타, 푸드 슬라이서와 야채 탈피기, 야채 캇타를 주로 이용하고 있었다. 3. 냉동 냉장고는 16개사에서 모두 보유하고 있었으나 냉장고의 용량을 늘려야 할 것으로 판단되었다. 4. 살균기로 자외선 살균기를 주로 사용하고 있었으나 살균시의 능력이 부족하고 살균기의 용량이 처리량에 비해 적었다. 5. 싱크 작업대는 16개사에서 모두 보유하고 있었으나, 싱크 작업대를 품목별로 구분하여 사용할 필요가 있었다. 6. 식품을 보온하거나 가온하는 기기류는 보유율이 대체로 낮았다. 7. 스팀발생용 에너지는 가스를 많이 사용하고 있었다. 8. 운반기는 평운반기, 키친 웨건을 주로 이용하고 있었다. 9. 포장기는 ???N 포장기가 주종을 이루고 있었으며 자동포장기, 집진기, 에어커텐 등의 기기류는 보완되어야 한다고 판단되었다.

• 한국정밀공학회지
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• 제26권8호
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• pp.96-103
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• 2009

The roll forming process is commonly used for the conventional 'Fe' metal products such as a furniture drawer guide or an up-down slide guide. Recently its applications are variously expanded to the sanitary facilities or electronic devices. It is essentially required the cleanness for the high technology application and any corrosion or rust are not allowed. Therefore, in those applications the stainless steel materials are strongly demanded as the substitution of 'Fe' steel. However the mechanical properties of stainless steel are not suitable for forming process compared with those of 'Fe' steel. Up to now, the conventional F.E.M.(Finite Element Method) has been used to analyze and design the roll forming process. The purpose of this research is to obtain the proper production process and the shape of rolls to manufacture the high precision slide rails made of stainless steel material. The commercial program, SHARPE-RF, is used to analyze the entire roll forming process. The results show that the rolling process and the roll design by F.E.M. are useful from the good agreement between the shapes of products estimated by F.E.M. and those of the actual products.

• Environmental Engineering Research
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• 제20권3호
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• pp.268-276
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• 2015

Solid waste production increases due to population and consumption increments. Landfill is the ultimate destination for all kinds of municipal solid waste; and is the most convenient waste disposal method in developing countries. To minimize investment and operational costs and society's opposition towards locating landfills nearby, proper landfill sizing and siting are essential. In this study, solid waste forecasting using Autoregressive Integrating Moving Average (ARIMA) was integrated with government future plans and waste composition to estimate the required landfill area for the state of Selangor, Malaysia. Landfill siting criteria were then prioritized based on expert's preferences. To minimize ambiguity and the uncertainty of the criteria prioritizing process, the expert's preferences were treated using integrated Median Ranked Sample Set (MRSS) and Analytic Hierarchy Process (AHP) models. The results show that the required landfill area is 342 hectares and the environmental criteria are the most important; with a priority equal to 48%.

• Journal of Advanced Marine Engineering and Technology
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• 제34권4호
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• pp.477-484
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• 2010

현재 국내 수산건조제품의 대부분은 천일(태양)건조에 의하는 실정으로 보관과 유통상의 위생안전성과 품질면에서 심각한 문제점을 안고 있다. 본 논문은 생산 현장에서 운용이 쉽고, 경제적이면서도 최고 건조품질을 유지할 수 있는 현장 지향적 저온진공 건조시스템의 설계 개발을 목표로 건조시간 경과에 따른 무게 감소율과 온도변동에 관한 실험적 결과를 요약하여 보고한 것이다.

• 상하수도학회지
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• 제14권4호
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• pp.318-327
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• 2000

Sludge production from water treatment plants is increasing each year because water resources deterioration is proceeding and water supply facilities are growing due to water demand increase. Water treatment plant sludges can be modified to soil cover in sanitary landfilling site through the lime treatment and other alternatives. The compression strength of $1.0kg/cm^2$ is necessary for the dozer operation on soft son cover material at municipal landfilling site. Modified sludge was experimentally produced in this study with lime, bentonite, loess, and activated loess dosing. X-ray diffraction patterns of the limed water treatment plant sludge confirmed the presence of calcium carbonate and ettringite. Unconfined compression strength properties of modified sludges showed material property improvement applicable for soil cover alternatives. When adding 20-30% activated loess to water treatment plant sludges. the modified sludges could reach the compression strength for cover soil after 7 days solidification reaction, but decrease of compression strength was intentioned in 28 days reaction period. Solidification effect of the modified sludge with activated loess was observed through the scanning electron microscope.

• Journal of Advanced Marine Engineering and Technology
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• 제26권2호
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• pp.226-232
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• 2002

In tradition, there have been two kinds of drying methods, which are sun drying and artificial drying. The sun drying method which has been adopted traditionally has been replaced by the hot-air drying method which is one of the most general methods of artificial drying, with its simple drying system, low initial cost of drying plant, and easy operating method. But the hot-air drying method has some defects ; (1)much energy loss happens due to the discharge of hot air during the drying process, (2)control of drying rate is not easy on account of changing relative humidity of inlet air for uniform hot air temperature, (3)high temperature of floods in drying process brings about the production of low-grade drying products. Also, the hot-air drying method is inducing environmental and sanitary problems which are resulting from the emission of high temperature and high humidity air, including stick on the drying progress. Vacuum drying technique, whose drying time and 7uantity of exhausting energy is about 1/3 ~1/4 of hot air drying, is very excellent in the drying efficiency. As the results, it took about 20 hours for material to reach about 18% of the final moisture content in order to store products for a long time, from about 470% of the early moisture content at the beginning of drying, and maximum drying rate comes to about $0.35 kg/m^2hr$ at about 350% of the moisture content.

• 한국물환경학회지
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• 제24권2호
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• pp.201-205
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• 2008

The korean government started to ban the sanitary landfill of food wastes as of 2005. The radical change of policy is primarily due to the limited landfill site, but aimed to promote not only to reduce the food waste production but also to enhance the reuse and recycle. The performance of elutriated acid fermentation to evaluate the effects of elutriating ratios was investigated. The fermenters were operated with elutriating water to food waste volumetric ratio of 2, 1, 0.5 and 0.25. Initial pH of elutriating water was set for 9 based on the pH effects study. The cumulative amounts of SCOD production rate were $0.34gSCOD/gVS_i$, $0.45gSCOD/gVS_i$, $0.26gSCOD/gVS_i$ and $0.28gSCOD/gVS_i$ with the ratios of 2, 1, 0.5 and 0.25, respectively. The cumulative productions of VFAs were 0.12 gVFAs as $COD/gVS_i$, 0.28 gVFAs as $COD/gVS_i$, 0.21 gVFAs as $COD/gVS_i$ and 0.14 gVFAs as $COD/gVS_i$ with the ratios of 2, 1, 0.5 and 0.25, respectively. The volume reduction were 58%, 52%, 45% and 47% with the ratios of 2, 1, 0.5 and 0.25, respectively.

• Coupled systems mechanics
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• 제12권6호
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• pp.531-537
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• 2023

Municipal solid waste landfills are unpredictable bioreactors which in cases of mishandling and bad supervision presents numerous risks. The key to municipal waste landfills is to approach them from the point of prevention of the possible consequences, which means using methods of organized waste disposal, and also utilizing landfill gas, as an unavoidable consequence with disposal of municipal solid waste with a high share of biodegradable organic matter. This paper presents an overview about problems of solid municipal waste management, type and composition of waste, and an overview of waste management condition. Further, the problem of landfill and landfill gasses is described with the calculation models of landfill production, as well as the use of the SWM GHG Calculator and LandGEM software on a specific example of gas production for the central zone at Sarajevo landfill "Smiljevici". Main focus of this thesis is the analysis of potentials of greenhouse gas emission reduction measures from the waste management. Overview of the best available techniques in waste management is presented as well as the methodology used for calculations. Scenarios of greenhouse gas emission reduction in waste management were defined so that emissions were calculated using the appropriate model. In the final section of the paper, its description of the problem of collection and utilization the landfill gas at the sanitary landfill "Smiljevici", and implementation of the system for landfill gas collection and solution suggestion for the gasification and exploitation of gas. Energy, environmental and economic benefits can be accomplished by utilizing municipal solid waste as fuel in industry and energy and moreover by utilizing energy generation from landfill gas, which this thesis emphasizes.