• 제목/요약/키워드: KG104

검색결과 324건 처리시간 0.026초

위성과 부이자료를 이용한 현.잠열 추정에 관한 연구 (Estimation of Sensible and Latent Heat Fluxes Using the Satellite and Buoy Data)

  • 홍기만;김영섭;윤홍주;박경원
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2001년도 춘계 학술대회 논문집 통권 4호 Proceedings of the 2001 KSRS Spring Meeting
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    • pp.104-110
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    • 2001
  • Ocean heat fluxes over a wide region are generally estimated by an aerodynamic bulk fromula. Though a remote sensing technique can be expected to estimated global heat flux, it is difficult to obtain air temperature and specific humidity at sea surface by a remote sensor. In this study present a new method with which to determine near-sea surface air temperature from in situ data. Also, These methods compared with other methods. A new method used a linear regression equation between sea surface temperature and air temperature of the buoys data. In this study new method is validated using observed monthly mean data at the Japan Meteorological Agency(JMA), National Data Buoy Center(NDBC) and Tropical Ocean-Global Atmosphere(TOGA)-Tropical Atmosphere Ocean(TAO) buoys. The result that bias and rmse are 0.28, 1.5$0^{\circ}C$ respectively. The correlation coefficient is 0.98. Also, to retrieve near-sea surface specific humidity(Q) from good nonlinear regression relationship between vapor pressure(Ea) of buoy data and air temperature, after obtained the third-order polynomial function, compared with that of estimated from SSM/I empirical equation by Schussel et al(1995). The result that bias and rmse are -1.42 and 1.75(g/kg).

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온도변화에 따른 음식쓰레기의 반응특성에 관한 연구 (A Study on the Reaction Characteristics of Food Garbage by the Variations of Temperature)

  • 허관;신대윤
    • 한국환경보건학회지
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    • 제24권1호
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    • pp.104-111
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    • 1998
  • The utilization of food garbage as composting was investigated by using the batch reactor and by varying the initial temperature of the fermentation reactors. As the straw controlled under 50 to 55% of moisture content and mixed 5% of EM(Effective Micro-organisms) microbial agent. An agitator continuously operated 1 rpm, supplying the amount of air(2l/kg.min). Reactor temperature changed three type of 40$\circ$C, 50$\circ$C, 60$\circ$C. In the case of 50$\circ$C operated 72 hr after organic contents showed lowest 48%, and weight reduction rate of showed 77%. The reaction gas was showed 30 min after 19. 9% of the lowest level at 20.9% concentration of oxygen and CO$_2$ gas was produced 0.9% due to organic disintegration on initial react time. NH$_4$, H$_2$ and CH$_4$ gas concentration showed 589 ppm lhr after, 83 ppm and 0.3%, but 8hr after gas product was complete. As using the straw of bulking agent, the Reduction by disintegration should be more effectively than composting.

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직접 결합방법에 의한 Glass-Ceramics과 금속의 접합 (Direct Sealing Glass-Ceramics to Metal)

  • 김환;이기강
    • 한국세라믹학회지
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    • 제18권2호
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    • pp.99-104
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    • 1981
  • Glass-ceramics possessed a number of characteristics which suggested their suggested their use for sealing to metals. The choice of particular glass-ceramics compositions for this application is governed by various factors, including workability of the glasses, thermal expansion characteristics and the matching of these to appropriate metals. Other properties, such as mechanical strength, determined the performance of glass-ceramics to metal seals. The purpose of the present study was to investigate direct sealing behaviour of copper to $Li_2O-ZnO-SiO_2$ system glass-ceramics. The design of the seal was a concentric seal which might contribute to the strong bond formation by providing compressive stress during thermal excursions. Tensile strengths of sealing layers were measured by Instron test machine. The layers were examined by electron probe microanalyzer. Crsystallization rate was increased with the amount of ZnO or $Li_2O$, and ZnO increased the sealing strength, but $Li_2O$ lowered it. Sealing mechanism was due to the formation of metal oxides, which acted as binder between copper and glass-ceramics. The nickle-plated copper seal with 10% $Li_2O$ and 30% ZnO was the most strong seal, and its sealing strength was more than 56kg/$\textrm{cm}^2$.

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자전거 허브 베어링의 구조적 내구성 해석에 관한 연구 (Structural Durability Analysis of Bike Hub Bearing)

  • 한문식;조재웅
    • 한국기계가공학회지
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    • 제14권3호
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    • pp.99-104
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    • 2015
  • As riders do not sense damage to hub bearings due to the friction that occurs while riding, unexpected accidents can happen. Hub bearings can also be broken by cracks due to minor impact. Therefore, the vibration analysis of bike hub bearings is thought to be important. Two bike hub bearings were modelled in this study. The bolts at both ends of the bearings were fixed. The standard weight of a Korean man was assumed to be 70Kg, and a force of 700N was applied. As a result of this study, maximum deformations occurred in bolts at both ends of the central axis. Regarding displacement due to natural frequencies, Model 2 had less deformation than Model 1. Using the results of this study, the structural safety of the design of hub bearings can be estimated, and design plans for durable hub bearings can be suggested.

Supplemental Fermented Milk Increases Growth Performance of Early-Weaned Pigs

  • Dunshea, F.R.;Kerton, D.J.;Eason, P.J.;King, R.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제13권4호
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    • pp.511-515
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    • 2000
  • Early weaning is a means of breaking the disease cycle from sow to piglet as well as capitalising on the enormous growth potential of the pig. However, the transition from milk to dry diets results in a growth check. Feeding of supplemental milk, fermented to reduce pH and enterotoxigenic bactetial proliferation, may be a means of gradually weaning pigs on to solid feed. This study involved 216 pigs weaned from the sow at 12 days of age, allocated to groups of 6 males and 6 females per weaner pen and allowed ad libitum access to a pelleted diet. In addition, half the pigs were given supplemental fermented skim milk for the first 8 days after weaning. Feeding supplemental fermented milk increased feed intake (104 vs. 157 g DM/d, p=0.011), average daily gain (-3 vs. 112 g/d, p<0.001) and feed conversion efficiency (0.01 vs. 0.81, p=0.003) over the first 8 days after weaning. The improvements observed in the supplemented pigs continued to be augmented such that, by 42 days of age, the pigs that had received supplemental fermented milk were heavier (9.6 vs. 11.5 kg, p=0.003) than their unsupplemented counterparts. Feeding fermented supplemental milk to early-weaned pigs can improve growth performance in the immediate and subsequent post-weaning period.

Estimating Predicted Environmental Concentration of Veterinary Antibiotics in Manure and Soil

  • Kwon, A-Young;Kim, Sung Chul
    • 한국토양비료학회지
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    • 제48권2호
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    • pp.100-104
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    • 2015
  • Adverse effect of veterinary antibiotics (VAs) released into environment has been issued recently and concerns about analysis and management for VAs in the environment were increased. Main objective of this research was to calculate predicted environmental concentration (PEC) of the VAs in soil based on avaiable statistical data and result of previous study such as consumption rate and physiological properties of VAs. Total of 5 VAs, Chlortetracycline (CTC), Oxytetracycline (OTC), Sulfadimethoxine (SDX), Sulfamethazine (SMT), and Tylosin (TYL) were examined. Result showed that calculated PEC value in manure and soil was ordered as SMT > TYL > SDX > CTC > OTC. Range of calculated value for manure and soil was 0.50-67.04 and $0.48-64.45mg\;kg^{-1}$ respectively. Comparing to measured concentration of VAs in manure and soil, lower concentration of VAs in manure and soil was evaluated due to fate and degradation of VAs in manure and soil. Overall, evaluated simple modeling for calculating PEC of VAs in manure and soil can be adapted for preliminary screening purpose in environmental risk assessment and more refined modeling is necessary to examine detailed assessment of VAs in manure and soil.

C57BLKS/J-db/db 마우스에서 흑삼의 당뇨 합병증 개선 효과 (Ameliorative Effect of Black Ginseng on Diabetic Complications in C57BLKS/J-db/db Mice)

  • 김애정;유현숙;강신정
    • 한국식품영양학회지
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    • 제25권1호
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    • pp.99-104
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    • 2012
  • The goal of this study was to examine the ameliorative effects of black ginseng(BG) in male obese diabetic C57BLKS/ J-db/db mice. Ten-week-old male db/db mice were administrated 300 mg/kg of F-BG daily for 6 weeks, The db/db mice where corresponded to the normal group and db/db mice which were the diabetic positive group were not provided BG treatment. The supressive effects of treatment were examined on serum lipids levels, which included total cholesterol, triglyceride, LDL-cholesterol and nonesterified fatty acid. Also, weight changes and the relative weight of liver and kidney, organ pathological investigation were measured. The effects of treatment were assessed by comparing the results of the db/db mice that received BG for 6 weeks with that of the diabetic positive group. Significant differences in several biological parameters such as HDL level(p<0.05), TG level(p<0.05) and NEFA level(p<0.05) were observed for the BG group. BG treatment increased the HDL level and decreased the NEFA level, which could ameliorate hyperlipidemia or blood circulation.

수평원관 내 이산화탄소의 증발열전달 특성 연구 (A Study on the Characteristics of Evaporative Heat Transfer for Carbon Dioxide in a Horizontal Tube)

  • 조은석;윤석호;김민수
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집B
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    • pp.104-107
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    • 2000
  • Evaporative heat transfer characteristics of carbon dioxide has been investigated. Experiment has been carried out for seamless stainless steel tube with outer diameter of 9.55 mm and inner diameter of 7.75 mm. Direct heating method is used for supplying heat to the refrigerant was uniformly heated by electric current which was applied to the tube wall. The saturation temperature of refrigerant is calculated from the measured saturation pressure by using an equation of state. Inner wall temperature was calculated from measured outer wall temperature, accounting for heat generation in the tube and heat conduction through the tube wall. Mass Quality of refrigerant was calculated by considering energy balance in the preheater and the test section. Heat fluxes were set at 12, 16, 20, 23, and $27kW/m^2$, mass fluxes were controlled at 212, 318, 424, and $530 kg/m^2s$, and saturation temperature of refrigerant were adjusted at 0, 3.4, 6.7 and $10.5^{\circ}C$. From this study, heat transfer coefficients of carbon dioxide have been provided with respect to quality for several mass fluxes, heat fluxes. Finally, the experimental results in this study are compared with the correaltion by Gungor and Winterton(1987).

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Comparison of Dietary Calcium and Iron Intake in Young Men Living Alone or Living with Roommates

  • Park, Young-Sook;Kim, Soon-Kyung;Byoun, Kwang-Eui
    • Journal of Community Nutrition
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    • 제4권3호
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    • pp.159-163
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    • 2002
  • A survey was performed to 238 male young men who were living alone (104 persons) or living with roommates (134 persons). Their average age was 22.6 years old, height 171.8cm, and weight 65.6kg. Their daily calcium intake level was averaged 271.9 $\pm$ 169.1mg, which was 38.8% of Korean Recommended Dietary Allowances(RDA). Comparing calcium intake of each mealtime, breakfast, lunch, dinner, and snacks were composed of 18.6%, 30.0%, 34.0% and 17.4%, respectively. Their daily iron intake level was averaged 8.9 $\pm$ 10.8mg, which was 74.3% of Korean RDA. Comparing iron intake of each mealtime, breakfast, lunch, dinner, and snacks were composed of 15.4%, 33.6%, 36.3% and 14.7%, respectively. Deficiency of these minerals in young male adults were severe and the nutrient qualities were also poor and the deficiency was more profound in calcium than in iron. And we observed iron nutrition differed significantly according to their living status, such as iron intake and its %RDA were significantly worse in single living subjects than the other. However calcium did not show significant difference. It was found mineral intake, especially iron, could be improved in young men living with roommates than living alone and regular breakfast could improve calcium and iron intakes. (J Community Nutrition 4(3) : 159~5163, 2002)

Differential gene expression pattern in brains of acrylamide-administered mice

  • Han, Chang-Hoon
    • 대한수의학회지
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    • 제52권2호
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    • pp.99-104
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    • 2012
  • The present study was performed to evaluate the relationship between the neurotoxicity of acrylamide and the differential gene expression pattern in mice. Both locomotor test and rota-rod test showed that the group treated with higher than 30 mg/kg/day of acrylamide caused impaired motor activity in mice. Based on cDNA microarray analysis of mouse brain, myelin basic protein gene, kinesin family member 5B gene, and fibroblast growth factor (FGF) 1 and its receptor genes were down-regulated by acrylamide. The genes are known to be essential for neurofilament synthesis, axonal transport, and neuroprotection, respectively. Interestingly, both FGF 1 and its receptor genes were down-regulated. Genes involved in nucleic acid binding such as AU RNA binding protein/enoyl-coA hydratase, translation initiation factor (TIF) 2 alpha kinase 4, activating transcription factor 2, and U2AF 1 related sequence 1 genes were down-regulated. More interesting finding was that genes of both catalytic and regulatory subunit of protein phosphatases which are important for signal transduction pathways were down-regulated. Here, we propose that acrylamide induces neurotoxicity by regulation of genes associated with neurofilament synthesis, axonal transport, neuro-protection, and signal transduction pathways.