• Title/Summary/Keyword: Total heat

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Reducing lesion incidence in pork carcasses by heating foot-and-mouth disease vaccine before injection

  • Cho, Jaesung;Ko, Eun Young;Jo, Kyung;Lee, Seonmin;Jang, Sungbong;Song, Minho;Jung, Samooel
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.4
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    • pp.634-639
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    • 2020
  • Objective: This study was conducted to investigate the effect of heating of foot-and-mouth disease (FMD) vaccine before injection, on the incidence of lesions at the injection site (pork butt), amount of discarded meat, and economical benefit. Methods: In total, 101,086 piglets raised in 30 farms, were vaccinated in the neck with 2 mL of FMD vaccine at 56 d and 84 d of age using a commercial syringe. The heat treatment group (48,511 pigs) was injected with the FMD vaccine after it had been heated in a water bath at 40℃ for 20 min. After slaughter, the incidence of lesions on the pork butt was inspected, and the subsequent amount of discarded meat was recorded. Results: Heat treatment of FMD vaccine reduced the incident rate of lesions on the pork butt (p<0.01). Overall, 17.81% of the pigs in the heat treatment group had lesions, while the incident rate in the control group was 21.70%. The amount of discarded meat per head of total pigs and per head of pigs with lesions were significantly lower in the heat treatment group than the control group (p<0.01). Thus, the proportion of discarded meat to dressed carcass was lower in the heat treatment group (0.249%) compared with the control group (0.338%) (p<0.01). Farms that rear 1,000 sows can gain 1,863,289 KRW (1,600 USD) in one year when they adopt heat treatment of FMD vaccine before injection. Conclusion: Heat treatment of FMD vaccine using simple heat equipment (water bath) can be effective in reducing lesions caused by FMD vaccination and increase the economic benefits in pig farms.

Comparing Solar Heat Shading Performances of Internal Blinds in the Summer (내측 블라인드의 하절기 일사열 차폐 성능 비교)

  • Park, Eun-Mi;Choi, Dong-Ho;Park, Min-Yong;Lee, Kyung-Hee
    • Journal of the Korean Solar Energy Society
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    • v.34 no.6
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    • pp.75-83
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    • 2014
  • Heat loss through windows and doors occupies 20 to 45% of the total heat loss in building. It accounts for a large proportion of the total heat loss in building. In order to suppress the amount of heat flow through the windows and doors were considered actions such as reinforcement of insulation performance of window, adoption of low-e glass, and installation of solar heat shading device. The Purpose of this study is to compare solar heat shading performances of 3 types of internal blinds in the summer. In order to verify the solar heat shading performances of the blinds, a roll blind, blind A(Venetian blind) and blind B(Daylight guiding venetian blind)were installed in the four rooms with the same environmental conditions. As a result of the experiment, the blind B, blind A, roll blind showed an excellent performance in that order. Its because the blind B is made of aluminum materials coated with special paints on surface. It doesn't converted to long wave by short wave light. and it is reflected to short wave to outside.

An Analysis of the Patents for Heat Pumps (열펌프의 정량적 특허기술 분석에 관한 연구)

  • Choi Jong Min;Kim Yongchan;Cheon Deokwoo;Shin Yun-Hee;Lee Sang Hyuk;Kwak Jae Su
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.17 no.9
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    • pp.808-815
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    • 2005
  • A technical analysis was conducted to predict the development trends for heat pump system. This study was based on submitted patents from 1983 to 2002 in Korea, USA, and Japan. The total number of raw data from the registered database was 19,261 and the obtained data to be analyzed through the filtering process was 5,143. Japan's technical development for the heat pump system was more dominant than the other countries. Approximately $54\%$ of the total patents related with the heat pump system was registered by Japan. The number of patents for the heat pump system registered by Korea was very low in 1980's, but it increased rapidly in 1990's. As a result, the number of patents applied by Korea was $21\%$ of all patents. When the patent was categorized into compression, absorption/ad-sorption, and chemical type, the technology of compression type made up over $80\%$ in each country. Approximately $93\%$ of the patents surveyed in this study was developed for air or water source heat pumps because of easy applications compared with other heat sources. The $89\%$ of all patents was applied by companies when applicants were divided into three groups of company, individual, and the others (national institute, university, and so on).

Trapezoidal Fin Analysis by the 3-D Analytical Method (3차원 해석적 방법에 의한 사다리꼴 휜 해석)

  • 이성주;강형석
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.4
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    • pp.388-397
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    • 2000
  • Comparison of the heat conduction into a trapezoidal fin and the heat loss from the fin by convection is made in this study Also, the ratio of heat loss from each surface to the total heat loss and the temperature distribution are analyzed using a 3-D analytical method. A trapezoidal fin whose tip height is half the root height is chosen as the model. The results show that the heat transfer rates from the tip and from both sides are comparable with each other as the non-dimensional width and length vary while the heat transfer rate from the bottom and top is dominant.

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Effects of Heat Treatment on the Dietary Fiber Contents of Soybean sprout and Spinach (가열처리에 의한 콩나물과 시금치의 식이섬유 함량변화)

  • Lee, Eun-Young;Kim, Young-A
    • Korean journal of food and cookery science
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    • v.10 no.4
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    • pp.381-385
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    • 1994
  • The dietary fiber contents of soybean sprout and spinach were changed by heat treatment. Before heat treatment, soybean sprout and spinach had larger amount of insoluble dietary fiber than soluble, and similar proportions of insoluble v/s soluble dietary fibers. After heat treatment, the value of insoluble dietary fiber of soybean sprout and spinach was increased significantly, except for microwave heating short time treatment. It is believed that the increment of insoluble dietary fiber is due to Maillard reaction products and resistant starch after heat treatment. The change of soluble dietary fiber contents of soybean sprout and spinach were not consistent in heat treatment. It is supposed that some soluble dietary fiber was destroyed by heat treatment, and some insoluble dietary fiber was hydrolysed or destroyed to be soluble. Total dietary fiber of soybean sprout and spinach was significantly incereased by all heat treatment, except for microwave heating short time of spinach.

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Heat Transfer Optimization in a Tube with Circular-Sectored Fins (원관내 부채꼴 휜 주위에서의 열전달 최적화)

  • Yoo, Jae-Wook;Kim, Sung-Jin;Hyun, Jae-Min
    • Proceedings of the KSME Conference
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    • 2000.04b
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    • pp.57-64
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    • 2000
  • The present work investigates the heat transfer characteristics for laminar fully developed forced convection in an internally finned tube with axially uniform heat flux and peripherally uniform temperature through analytical models of convection in a porous medium. Using the Brinkman-extended Darcy flow model and the two equation model fur heat transfer, analytical solutions fur fluid flow and heat transfer are obtained and compared with the exact solution for fluid flow and the numerical solutions for conjugate heat transfer to validate the porous medium approach. Using the analytical solutions, parameters of engineering importance are identified and their effects on fluid flow and heat transfer are studied. Also, the expression fur total thermal resistance is derived from the analytical solutions and minimized in order to optimize the thermal performance of the internally finned tubes.

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Effect of Air Content on the Heat Transfer Characteristics of Nonwoven Insulating Materials (부직포내 공기함량이 열전달에 미치는 영향)

  • 김희숙;김은애
    • Journal of the Korean Society of Clothing and Textiles
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    • v.18 no.2
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    • pp.244-251
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    • 1994
  • The purpose of this study was to analyze conductive convective and radiative heat transfer characteristic of the nonwovens were studied by measuring thermal conductance at atmospheric and low air pressure. The results obtained were as follows . 1) As thickness of air layer Increased, overall heat transfer was decreased by reducing conductive and radiative heat trasfer. 2) The conductive and convective heat trasfer by air were in the range of 79~8971 of overall heat transfer. 3) As thickness of nonwoven increased for a given solidity, overall heat trasfer was decresed by increasing total thickness of air layer and by reducing conductive and radiative heat transfer. 4) For a given weight, increasing thickness is more effective than increasing solidity.

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A study on airside performance of finned-tube heat exchanger according to fin combination and fin pitch variation of using large scale model (확대모형을 이용한 휜-관 열교환기의 휜 형상 및 휘 간격 변화에 따른 공기측 성능에 관한 연구)

  • Byun, Ju-Suk;Jeon, Chang-Duk;Lee, Jin-Ho;Kim, Jin-Woo
    • Proceedings of the SAREK Conference
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    • 2005.11a
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    • pp.281-287
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    • 2005
  • This study investigates the pressure drop and heat transfer characteristics of heat exchanger according to the combination of fin configuration and fin pitch of each row by the similitude experiments with the finned-tube geometry scaled as large as four times Finned-tube heat exchanger has 2 rows, and fin geometry consists of two cases, louver-louver and louver-slit. Fin pitch is varied with three types in each case, 6-6 mm, 8-8 mm and 8-6 mm. Results show that total heat transfer can be occurred evenly at each row by varying the fin pitch of 1st row and 2nd row. Heat transfer rate and pressure drop characteristics change according to the combination for fin geometry and fin pitch.

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Forced convective boiling heat transfer for a ternary refrigerant mixture inside a horizontal tube (수평관내 3성분 혼합냉매의 강제대류비등 열전달)

  • 오종택
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.6
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    • pp.912-920
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    • 1999
  • The forced convective boiling heat transfer coefficients of R-407C were measured inside a horizontal tube 6.0mm I.D. and 4.0m long. The heat transfer coefficients increased according to an increase in heat flux at constant mass flux. Because nucleation was completely suppressed in the two-phase flow region with high quality, heat transfer coefficients in forced convective evaporation were higher than those in nucleate boiling region. Average heat transfer coefficients of R-407C were about 30 percent lower than the pure refrigerant correlation, due to mass transfer resistance at the gas-liquid interface. However, the total experimental data shows an agreement with the predicted data for ternary refrigerant mixtures with a mean deviation of 30%.

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Heat Transfer and Friction Characteristics of Slit Fin and Tube Heat Exchangers in Wet Conditions (습표면 조건에서 슬릿 핀-튜브 열교환기의 열전달 및 압력강하 특성)

  • Chang, Keun-Sun;Phan, Thanh-Long
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.19 no.1
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    • pp.1-9
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    • 2007
  • Water condensate accumulated on the surface of a fin-and-tube heat exchanger significantly affects its thermal and hydraulic performance. The purpose of this study is to investigate the effect of condensate retention on the air-side heat transfer performance and flow friction. Total 12 samples of slit and plate fin-and-tube heat exchangers with varying fin spacing and number of tube rows are tested under dry and wet conditions. The thermal fluid measurements are made using a psychometric calorimeter. Frontal air velocity varies in the range from 0.7 m/s to 1.5 m/s. Using the experimental data, presented are the heat transfer coefficients in terms of Colburn j-factor and friction factor.