• Journal of Animal Environmental Science
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• v.2 no.2
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• pp.123-133
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• 1996

Recently, a greater interest has been placed on the methods of acration control for management of maloders during composting. This study was performed to evaluate the influence of the intermittent aeration method on the composting temperature and chemical components. Combinatoins of cattle manure and rice hulls were placed on a batch composter(3,150-L size) practically designed. The chemical properties of the produced compost were suitable for plant growth, when composting temperature was maintained in the range from 45 to $66^{\circ}C$ for 42 days. It should be noted that cooling effect of intake air was not significant because air temperature was as high as $30^{\circ}C$. Heat and aeration loss from the composter did not affect biomass decomposition by microbes during composting. Mixtures of materials with C/N ratios higher than 30 required longer composting period.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.398-399
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• 2008

Enhanced performances of high temperature superconducting (HTS) cable attract tremendous interests of the power utility. However, the reliability issue as the power system is still in controversy. To verify the reliability of HTS cable, 22.9 kV HTS cable system with the specification of 100 m length, 50 MVA capacity, and open refrigeration cooling system was laid on Gochang power testing center of KEPCO in 2006. During the test period, the current transport characteristics, the fundamental function of power cable, have been monitored and investigated precisely. In this paper, the heat loss and AC loss measured at various current load conditions are described and discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.1
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• pp.47-52
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• 1990

During prolonged exposure to the sun for 8 h each day for 10 days in which the highest ambient temperature around 14:00 h was $39^{\circ}C$, buffaloes exposed to the sun without shade increased the turnover of body water by 35% and 76% on day 5 and day 10 of exposure respectively. The total body water markedly decreased on day five and this amount was maintained thereafter. Plasma and blood volumes did not change significantly on day five but markedly decreased on day 10. Packed cell volume significantly decreased on day five and day 10 of the exposure period. The reduction of packed cell volume on day 10 coincided with the decrease in total plasma water. On day 10 of the exposure, an increase in the rate of liquid flow from the rumen was noted. It is concluded that on the fifth day of exposure, the increase in the evaporative cooling process was attributed to initial mobilization of water from the intracellular compartment. The reduction of both plasma and cell volumes occurring from day five to day 10 indicated a loss of body water from both intracellular and extracellular compartments.

• Journal of Biosystems Engineering
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• v.32 no.1 s.120
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• pp.20-29
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• 2007

Korean farmers have purchased agricultural dryer and low temperature storage system apart. In this study, the system was designed and constructed to investigate the practical application possibility of the air to air heat pump as drying and low temperature storage system for agricultural products with providing basic data. The performance and drying characteristics of the system evaluated by drying red pepper. The value of coefficient of performance of the system for heating was from 1.8 to 2.2 when ambient air temperature varied from 13$^{\circ}C$ to 23$^{\circ}C$. For operating the heat pump as dryer for drying red pepper by setting three drying air temperature of 50, 55 and 60$^{\circ}C$, specific moisture extraction rates meaning amount of energy consumption for removing moisture of 1kg from red pepper were 1.095, 1.017 and 1.094 kg$_{water}$/kWh, respectively. The drying period up to moisture ratio of 0.02 were 31, 26 and 21 hour, respectively. The lightness, redness, yellowness and chroma differences of red pepper dried by the heat pump dryer were lowered than those of red pepper dried by conventional heated air dryer except for yellowness difference at drying air temperature of 60$^{\circ}C$.

• Journal of Chest Surgery
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• v.24 no.7
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• pp.669-673
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• 1991

Fructose-l, 6-diphosphate as an additive to cold crystalloid cardioplegia [St. Thomas sol.] was studied prospectively in 60 patients undergoing open heart surgery from January 1, 1991, to June 30, 1991. Thirty patients received cardioplegia with FDP[group I ] and 30 patients received cardioplegia without FDP [group II ]. There were no differences between two groups pre-operatively with regard to age, heart disease, cross-clamp time, cardiac enzymes, or hemodynamic measurements [p>0.05]. Cardiopulmonary bypass was established using ascending aorta and vena cava cannulation employing moderate systemic hypothermia [30oC nasopharyngeal temperature] and hemodilution All patients received cardioplegia through the aortic root at aortic root pressure of 80mm Hg. The composition of the cardioplegic solution and its delivery were identical in both groups except for the addition of FDP[1.5 mg/mL] in group I. The cardioplegic infusate consisted of St. Thomas Hospital solution. The initial dose was infused through the aortic root. Topical myocardial cooling with saline slush was employed in all patients. Recorded operative data were cardiopulmonary bypass and cross-clamp times, amount of cardioplegic infusate. Blood samples for assessment of lactate dehydrogenase [LDH], creatine kinase [CK] and transaminases [GOT, GPT] were obtained before and at 1,2,3,7th postoperative period. Better myocardial protection effect was noted in group I than group II with respect to the % change of cardiac enzymes, although the differences were not significant. We conclude that FDP is a safe additive to crystalloid cardioplegia and may be beneficial in open heart surgery patients.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.372-374
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• 2008

Korea classified into a development country when UNFCCC was concluded in 1995. So Korea doesn't have a GHG reduction duty until 2012. As the UNFCCC is strengthened, recently there is a growing interest in renewable energy and energy usage efficiency improvement for reducing GHG emission. It is associated with CES and renewable energy. CES is a total energy (heat, cooling and power)supplier in aggregated demand zone like a hotel, building, hospital and redevelopment district using CHP and it improves energy usage efficiency. At present, renewable energy is needed for GHG reduction duty but renewable energy doesn't have economic feasibility. So renewable energy is needed various support system to popularize which is a FIT and RPS. Especially RPS is carrying out instead of FIT in many advanced country and it will be inroduced in Korea. RPS is a duty which electricity service provider must guarantee renewable energy as much as specific ratio of total capacity. Therefore this study conducts an economic feasibility estimation of CES considering renewable energy when RPS will introduced in the future.

• Progress in Superconductivity and Cryogenics
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• v.16 no.4
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• pp.62-65
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• 2014

To minimize most heat loss of current lead for high-temperature superconducting (HTS) rotating machine, the choice of conductor properties and lead geometry - such as length, cross section, and cooling surface area - are one of the various significant factors must be selected. Therefore, an optimal lead for large scale of HTS rotating machine has presented before. Not let up with these trends, this paper continues to improve of diminishing heat loss for HTS part according to different model. It also determines the simplification conditions for an evaluation of the main flux flow loss and eddy current loss transient characteristics during charging and discharging period.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.1 no.2
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• pp.1-6
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• 2005

Ground water source heat pumps are clean, energy-efficient and environment-friendly systems for cooling and heating. Although the initial cost of ground water source heat pump system is higher than that of air source, it is now widely accepted as an economical system since the installation cost can be returned within a short period of time due to its high efficiency. In a ground water source heat pump system, the variation of the ground water temperature is an important factor that influences the system performance. In this study, variation of the ground water temperature of a single well system is studied experimentally for various operating conditions. When ground water flow exists in the underground, the returned water exchanges heat efficiently with the ground and the temperature of the ground water remains nearly constant. Hence the short circuit problem is minimized. If an active flow of ground water flow exists in the underground, a singe well heat pumps system will be free of short circuit problem and can operate with high performance.

• Journal of Radiation Protection and Research
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• v.36 no.4
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• pp.174-182
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• 2011

With the reactor operation conditions - 4.3 wt% $^{235}U$ initial enrichment, burn-up 55,000 MWd/MTU, average power 34 MW/MTU for three periods burned time for 539.2 days per period and cooling time for 100 hours after shut down, to set up the condition to determine the minimum height (depth) of spent fuel storage pool to shut off the radiation out of the spent fuel storage pool and to store spent fuels safely, the dose rate on the specific position directed to the surface of spent fuel storage pool induced by the neutron and gamma-ray from spent fuels are evaluated. The length of spent fuel is 381 cm, and as the result of evaluation on each position from the top of spent fuel to the surface of spent fuel storage pool, it is difficult for neutrons from spent fuels to pass through the water layer of maximum 219 cm (600 cm from the floor of spent fuel storage pool) and 419 cm (800 cm from the floor of spent fuel storage pool) for gamma-ray. Therefore, neutron and gamma-ray from spent fuels can pass through below 419 cm (800 cm from the floor) water layer directed to the surface of spent fuel storage pool.

• Nuclear Engineering and Technology
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• v.47 no.3
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• pp.227-239
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• 2015

The thermal, mechanical, and neutronic performance of the metal alloy fast reactor fuel design complements the safety advantages of the liquid metal cooling and the pool-type primary system. Together, these features provide large safety margins in both normal operating modes and for a wide range of postulated accidents. In particular, they maximize the measures of safety associated with inherent reactor response to unprotected, doublefault accidents, and to minimize risk to the public and plant investment. High thermal conductivity and high gap conductance play the most significant role in safety advantages of the metallic fuel, resulting in a flatter radial temperature profile within the pin and much lower normal operation and transient temperatures in comparison to oxide fuel. Despite the big difference in melting point, both oxide and metal fuels have a relatively similar margin to melting during postulated accidents. When the metal fuel cladding fails, it typically occurs below the coolant boiling point and the damaged fuel pins remain coolable. Metal fuel is compatible with sodium coolant, eliminating the potential of energetic fuel-coolant reactions and flow blockages. All these, and the low retained heat leading to a longer grace period for operator action, are significant contributing factors to the inherently benign response of metallic fuel to postulated accidents. This paper summarizes the past analytical and experimental results obtained in past sodium-cooled fast reactor safety programs in the United States, and presents an overview of fuel safety performance as observed in laboratory and in-pile tests.