• Title/Summary/Keyword: 에너지 정의

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Heating Performance of Hot Water Supplying System in Greenhouse (온수배관을 이용한 온실의 난방성능)

  • Yoon, Yong-Cheol;Shin, Yik-Soo;Kim, Hyeon-Tae;Bae, Seoung-Beom;Choi, Jin-Sik;Suh, Won-Myung
    • Journal of Bio-Environment Control
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    • v.21 no.2
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    • pp.79-87
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    • 2012
  • This research was conducted to obtain basic data with regard to the heating performance that would be produced by installing an aluminum hot water pipe inside the greenhouse with the goal of reducing the heating energy in greenhouse. The research results are summarized as follows. The degree of difference in relation to the temperature by height within the greenhouse during the entire experiment was significant - within the range of 4.0~$7.0^{\circ}C$. The temperature difference between incoming and outgoing water was about $3.3^{\circ}C$ greater when FCU was activated compared to when it was not activated. Meanwhile, the amount of energy consumed increased about 36.2~40.1%. The amount of pyrexia per hour also increased by 44.6~52.0%. During the experiment period, circulated flux was within the range of 0.48~$0.49L{\cdot}s^{-1}$ while average fluid speed was 1.53~$1.56m{\cdot}s^{-1}$. The average temperature difference between incoming and outgoing water was 6.24~$11.50^{\circ}C$. The amount of heating value by each set temperature within the minimum outdoor temperature range of -14.0~$-0.6^{\circ}C$ was 135,930~307,150 kcal, and the range was within the 9,610~$19,630kcal{\cdot}h^{-1}$ per hour. This demonstrated that about 23~53% heating energy of the maximum heating load could be supplied. Total radiating value and amount of energy consumed were 2,548,306 kcal and 3,075.7 kWh, respectively. When heating takes place using oil, which is a fossil fuel, the total amount of light oil consumed was 281.6 L while the cost was 321,000 won. When the electricity cost for farms is applied, the total cost was about 110,730 won, which is about 33.5% of the cost required compared to oil consumption. The temperature at in the experiment area was about 8.3~$14.6^{\circ}C$ higher compared to that of the control area.

LCA on Lettuce Cropping System by Top-down Method in Protected Cultivation (시설상추 생산체계에 대한 top-down 방식 전과정평가)

  • Ryu, Jong-Hee;Kim, Kye-Hoon;So, Kyu-Ho;Lee, Gil-Zae;Kim, Gun-Yeob;Lee, Deog-Bae
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.6
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    • pp.1185-1194
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    • 2011
  • This study was carried out to estimate carbon emission using LCA (Life Cycle Assessment) and to establish LCI (Life Cycle inventory) DB for lettuce production system in protected cultivation. The results of data collection for establishing LCI DB showed that the amount of fertilizer input for 1 kg lettuce production was the highest. The amounts of organic and chemical fertilizer input for 1 kg lettuce production were 7.85E-01 kg and 4.42E-02 kg, respectively. Both inputs of fertilizer and energy accounted for the largest share. The amount of field emission for $CO_2$, $CH_4$ and $N_2O$ for 1 kg lettuce production was 3.23E-02 kg. The result of LCI analysis focused on GHG (Greenhouse gas) showed that the emission value to produce 1 kg of lettuce was 8.65E-01 kg $CO_2$. The emission values of $CH_4$ and $N_2O$ to produce 1 kg of lettuce were 8.59E-03 kg $CH_4$ and 2.90E-04 kg $N_2O$, respectively. Fertilizer production process contributed most to GHG emission. Whereas, the amount of emitted nitrous oxide was the most during lettuce cropping stage due to nitrogen fertilization. When GHG was calculated in $CO_2$-equivalents, the carbon footprint from GHG was 1.14E-+00 kg $CO_2$-eq. $kg^{-1}$. Here, $CO_2$ accounted for 76% of the total GHG emissions from lettuce production system. Methane and nitrous oxide held 16%, 8% of it, respectively. The results of LCIA (Life Cycle Impact assessment) showed that GWP (Global Warming Potential) and POCP (Photochemical Ozon Creation Potential) were 1.14E+00 kg $CO_2$-eq. $kg^{-1}$ and 9.45E-05 kg $C_2H_4$-eq. $kg^{-1}$, respectively. Fertilizer production is the greatest contributor to the environmental impact, followed by energy production and agricultural material production.

Resting Energy Expenditure in Patients with Lung Cancer (폐암 환자의 안정시 에너지 소비)

  • Lee, Jae-Lyun;Kim, Ki-Beom;Lee, Hak-Jun;Jung, Jin-Hong;Lee, Kwan-Ho;Lee, Hyun-Woo
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.5
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    • pp.1019-1029
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    • 1997
  • Background : Elevation of resting energy expenditure(REE) in patients with lung cancer has been described in earlier studies and may contribute to cancer cachexia, but limited information is available regarding the prevalence and determinants of the increased REE. The aim of this study was to assess the prevalence and contributing factors of a hypermetabolic state in newly detected patients with lung cancer and to assess the energy balance in order to improve our knowledge about weight loss in patients with lung cancer. Method : Thirty one consecutive, newly detected patients with lung cancer and 20 control patients with benign lung diseases were included in this study. Resting energy expenditure(REE) was measured by indirect calorimetry using ventilated hood system and predicted REE was calculated by the Harris-Benedict formular. Results : The energy balance in newly detected lung cancer patients was disturbed in a high proportion of patients, and hypermetabolic state occurred in 61% of the patients. Tumor volume, cancer type, location, stage, the presence of atelectasis or infiltration, pulmonary function, or smoking behavior were not associated with increase in REE. But patients with distant metastasis had significantly higher REE comparing with patients without metastasis. Thirty nine percents of the patients with lung cancer had substantial loss of more than 10% of their pre-illness weight. Weight losing patients with lung cancer were not accompanied by an increase in REE. Conclusion : We concluded that the REE was elevated in a higher proportion of patients with lung cancer and distant metastasis was found to be contributing factor to the elevated REE.

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Effect of 5 Week Long High-Fat Diet on Energy Metabolic Substrate Utilization and Energy Content Evaluation of Dietary Fat (5주간의 고지방식이 섭취시 흰쥐의 에너지 대사 기질 이용과 식이지방에너지 평가에 관한 연구)

  • Hwang, Hye-Jung;Kim, Ji-Su;Suh, Hea-Jung;Lim, Ki-Won
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.8
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    • pp.1094-1099
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    • 2012
  • This study investigated the effect of a long-term high-fat diet on energy metabolic substrate utilization in resting rats in order to revalue source fat energy efficiency during a high-fat diet and its effect on energy expenditure and body fat accumulation. Sprague-Dawley male rats at 4 weeks of age were bought from Orient Bio Con. The rats were divided into a control (CON) group and a high-fat diet (HF) group. Rats ate a high-fat diet (w/w 40%, kcal/kcal 64.9%) ad libitum for 5 weeks. Food intake and body weight were measured every day at 09:00 throughout the experimental period. Energy expenditure was measured using an animal energy metabolism chamber after 4 weeks. The final body weight did not change between the CON and HF groups, but caloric intake was significantly higher in the HF group than in the CON group (p<0.05). There was no difference between the groups in oxygen uptake, however carbon dioxide production was significantly higher in the HF group. Also, the respiratory exchange ratio was higher in the HF group. Carbohydrate oxidation was lower in the HF group than in the CON group, but fat oxidation in the HF group was greater. These results mean that energy substrate oxidation at rest is affected by diet composition, especially dietary fat content. Abdominal fat fad weights were significantly higher by 33% in the HF group than in the CON group even though the calorie intake in the HF group was higher by 6%. These results suggested that the dietary fat calorie value might have a higher Atwater value of 9 kcal/g, which mean that dietary fat calorie values could be reconsidered in body weight control scenarios such as which the obese or weight class athletes.

Effects of Different Energy and Protein Level of TMR on Milk Production of Dairy Goats in Early Lactation (TMR의 에너지 및 단백질 수준이 비유초기 유산양의 유생산성에 미치는 영향)

  • Ki, Kwang-Seok;Lee, Hyun-June;Kim, Sang-Bum;Lee, Wang-Shik;Lim, Dong-Hyun;Lim, Hyun-Joo;Park, Sung-Jai;Cho, Won-Mo;Kim, Hyeon-Shup;Jin, Ze-Lin;Lee, In-Duk;Kim, Wan-Young;Jeo, Joon-Mo
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.30 no.3
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    • pp.267-274
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    • 2010
  • The objective of this experiment was to investigate effects of total mixed ration (TMR) of different nutrition level on milk production in dairy goats (Sannen). Twenty four lactating goats were randomly assigned to one of four TMRs; medium energy-medium crude protein (CP) TMR (control), high energymedium CP TMR (T1), medium energy-high CP TMR (T2) and high energy-high CP TMR (T3). The content of total digestible nutrients (TDN) and CP in the control diet were 67.0% and 13.9%. The TDN content of the high energy TMR was 73.7% and the CP content of the high CP TMR was 15.3%. Milk yield was significantly (P<0.05) higher for T1 ($2,198{\pm}115 ml$) than for T2 ($1,742{\pm}52 ml$) and T3 ($1,984{\pm}90 ml$). But there were no significant differences in milk composition between the treatments. Daily body weight gain was increased in T1 and T3 but reduced in control and T2. The result of the present study showed that dietary energy level supplied more than that of NRC recommendation did not affect milk yield of dairy goats in early lactation but prevented body weight loss.

Experimental Study with Respect to Dose Characteristic of Glass Dosimeter for Low-Energy by Using Internal Detector of Piranha 657 (Piranha 657의 Internal Detector를 이용한 저에너지에서 유리선량계의 선량 특성에 관한 연구)

  • Son, Jin-Hyun;Min, Jung-Whan;Kim, Hyun-Soo;Lyu, Kwang-Yeul;Lim, Hyun-Soo;Kim, Jung-Min;Jeong, Hoi-Woun
    • Journal of radiological science and technology
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    • v.35 no.2
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    • pp.119-124
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    • 2012
  • Recently, Glass Dosimeter (GD) with thermoluminescent Dosimeter (TLD) are comprehensively used to measure absorbed dose from diagnostic field to therapy field that means from low energy field to high energy field. However, such studies about dose characteristics of GD, such as reproducibility and energy dependency, are mostly results in high energy field. Because characteristic study for measurement devices of radiation dose and radiation detector is performed using 137Cs and 60Co which emit high energy radiations. Thus, this study was evaluated the linearity according to Piranha dose which measured by changing tube voltage (50kV, 80kV and 100kV which are low energy radiations), reproducibility and reproducibility according to delay time using GD. Measurement of radiation dose is performed using internal detector of Piranha 657 which is multi-function QA device (RTI Electronic, Sweden). Condition of measurement was 25mA, 0.02sec, 2.5mAs, SSD of 100 cm and exposure area with $10{\times}10cm^2$. As above method, GD was exposed to radiation. Sixty GDs were divided into three groups (50kV, 80kV, 100kV), then measured. In this study, GD was indicated the linearity in low energy field as high energy existing reported results. The reproducibility and reproducibility according to delay time were acceptable. In this study, we could know that GD can be used to not only measure the high energy field but also low energy field.

A Study on Direct Cooling and Washing Machine for Energy Saving-Type Dyeing Machine (에너지 절감형 염색기용 직접냉각수세장치에 대한 연구)

  • Han, Seung-Chul;Kim, Jin-Ho;Kim, Je-Hoon;Lee, Sung-Kyu
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.2
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    • pp.485-491
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    • 2012
  • Due to increase in production of the domestic textile industry, energy consumption in textile industry is still growing. Traditional dyeing machine has high temperature and pressure. Accordingly, it uses an indirect cooling system that utilize a heat exchanger to cool after the dyeing. However, this indirect cooling system consumes a great deal of water, takes prolonged periods of time to process and, most importantly, because of the condensing of the dye at the cooling stage requires further energy in reduction cleaning and washing process. Therefore, in this paper, we propose a direct cooling washing machine that replaces the traditional indirect cooling system to provide coolant into the dyeing machine. The newly proposed direct cooling washing machine will still use parts of the traditional dying but will be able to skip the cooling as well as the reduction cleaning and washing process, resulting in less processing time and lower energy consumption. Also, we made a prototype. The prototype was applied to dyeing machine to test the direct cooling washing machine's ability and dyeing property. Additionally, we compared indirect cooling washing machine with direct cooling washing machine about ability, material and energy saving assessment.

Estimation of Annual Energy Production Based on Regression Measure-Correlative-Predict at Handong, the Northeastern Jeju Island (제주도 북동부 한동지역의 MCP 회귀모델식을 적용한 AEP계산에 대한 연구)

  • Ko, Jung-Woo;Moon, Seo-Jeong;Lee, Byung-Gul
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.18 no.6
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    • pp.545-550
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    • 2012
  • Wind resource assessment is necessary when designing wind farm. To get the assessment, we must use a long term(20 years) observed wind data but it is so hard. so that we usually measured more than a year on the planned site. From the wind data, we can calculate wind energy related with the wind farm site. However, it calculate wind energy to collect the long term data from Met-mast(Meteorology Mast) station on the site since the Met-mast is unstable from strong wind such as Typhoon or storm surge which is Non-periodic. To solve the lack of the long term data of the site, we usually derive new data from the long term observed data of AWS(Automatic Weather Station) around the wind farm area using mathematical interpolation method. The interpolation method is called MCP(Measure-Correlative-Predict). In this study, based on the MCP Regression Model proposed by us, we estimated the wind energy at Handong site using AEP(Annual Energy Production) from Gujwa AWS data in Jeju. The calculated wind energy at Handong was shown a good agreement between the predicted and the measured results based on the linear regression MCP. Short term AEP was about 7,475MW/year. Long term AEP was about 7,205MW/year. it showed an 3.6% of annual prediction different. It represents difference of 271MW in annual energy production. In comparison with 20years, it shows difference of 5,420MW, and this is about 9 months of energy production. From the results, we found that the proposed linear regression MCP method was very reasonable to estimate the wind resource of wind farm.

The Limiting Drift and Energy Dissipation Ratio for Shear Walls Based on Structural Testing (전단벽의 최소 층변위 및 에너지 소산성능)

  • ;;N.M.Hawins
    • Magazine of the Korea Concrete Institute
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    • v.10 no.6
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    • pp.335-343
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    • 1998
  • Recently, new experimental criteria for reinforced concrete frame structures in high seismic regions have been reported in United States. The objective of the criteria is to get more reliable test data which are valid to compare with other test data done by different researchers. The criteria precribe test method of specimens, analysis method of test data, and limiting values needed to specimens like drift angle, energey dissipation ratio, stiffness, and strength. These criteria might be usefel to get objective conclusion. Shear wall structures, which belong to one of earthquake resisting systems, also need this kind of criteria. But, the general response of shear wall structures is a little bit different from that of frame structures since shear wall restrains the horizontal displacement caused by horizontal force and increases the stiffness and strength. The objective of this paper is to propose a criterion for limiting drift and energy dissipation ratio of shear walls based on structural testing. These are the most important values for presenting the capacity of shear walls. Limiting drift and energy dissipation ratios were examined for tests on shear walls having ductile type failures. Test data were analyzed and compared to the results for a suggested acceptance criteria that involve a limiting drift that is a function of aspect ratio and a limiting energy dissipation ratio that is a function of displacement ductility and damping.

Comparison of Surface Fluxes Based on Landuse Characteristics Near Gangjeong-Goryeong Weir of the Nakdong River (낙동강 강정고령보에서 관측된 플럭스의 지표면에 따른 특성 비교)

  • Kahng, Keumah;Koo, Hae-Jung;Byon, Jae-Young;Park, Young-San;Jung, Hyun-Sook
    • Journal of the Korean earth science society
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    • v.34 no.6
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    • pp.561-574
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    • 2013
  • This study investigates energy fluxes measured near Gangjeong-Goryeong Weir of the Nakdong River of South Korea for more than a year, from July 2011 to September 2012, in order to analyze the applicability of the data for future impact analyses. Each of the two study sites is located in a rural area, surrounded by agricultural fields, and an urban industrial area. Sensible and latent heat fluxes are analyzed according to the wind direction. In the summertime, when the wind blows from the river, sensible heat tends to decrease and latent heat tends to increase at both sites. This result is considered to be caused by moisture transfer from the river. Bowen ratio, energy balance closure, momentum flux, and stability are analyzed as well. The Bowen ratio of the rural agricultural site turns out higher than that of the urban site regardless of the season. The energy balance closure is higher at the agricultural site compared to the urban area, which is mainly due to exclusion of the storage term calculation at the urban site. The momentum flux is greater at the urban site both in winter and summer. The instability lasts longer during daytime and in the summertime, when there is a strong turbulence. The data from these sites are appropriate to be used in analyzing the impact of river in surrounding areas for future studies.