• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.3
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• pp.113-124
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• 2012

Reliable estimation of energy load inside the greenhouse and the selection of cooling and heating facilities are very important preceding factors to save energy as well as initial and maintenance costs of operating a greenhouse. Recently, building energy simulation (BES) technique to simulate a model similar to the actual conditions through a variety of dynamic simulation methods, and predict and analyze the flow of energy is being actively introduced and developed. As a fundamental research to apply the BES technique which is mainly used for analysis of general buildings, to greenhouse, this research designed four types of naturally-ventilated greenhouses using one of commercial programs, TRNSYS, and then compared and analyzed their energy load properties, by applying meteorological data collected from six regions in Korea. When comparing the greenhouse load of each region depending on latitude and topographical characteristics through simulation, Chuncheon had nearly 9~49 % higher heating load per year than other regions, but its annual cooling load was the reverse to it. Except for Jeju, 1-2W type greenhouses in five regions showed about 17 % higher heating load than a widespan type greenhouse, and 1-2W type greenhouses in Chuncheon, Suwon, Cheongju, Daegu, Cheonju and Jeju had 23 %, 20 %, 17 %, 16 %, 18 % and 20 % higher cooling load respectively than a wide span-type one. Glasshouse and vinyl greenhouse showed 8~11 % and 10~12 % differences respectively in heating load, while 2~10 % and 7~10 % differences in cooling load respectively.

• The Transactions of the Korean Institute of Power Electronics
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• v.11 no.4
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• pp.340-348
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• 2006

This paper proposes an inrush current control technique of matching transformer for configuration of dynamic voltage restorer(DVR). The DVR system consist of PWM inverter to inject arbitrary voltage, LC low pass filter as harmonic eliminator and matching transformer for isolation. However, the matching transformer has an excess of inrush current by magnetic flux saturation in the core. Due to this inrush current, the rating of matching transformers is double for needed nominal rating for protection of DVR. Therefore, in this paper, the modeling method of magnetic flux saturation is used to analyze a magnitude of inrush current, and additional current controller is used for PWM inverter output regulation. Simulation and experimental results are provided to demonstrate the validity of the proposed control method.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.15 no.3
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• pp.45-50
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• 2001

Fuzzy theory is used to quantify some subjective criteria and consider uncertain factors for transmission line reinforcement planning in this paper. Sugeno's fuzzy integral is also used in the proposed method, because it can be easily allied to multi attribute decision making problems such as power system planning. To verify the proposed algorithm, some bode-neck lines are searched for the case that the amount of Maximal Load Supplying Capability(MLSC) is small using the results of contingency analysis for Korea Electric Power Corporation(KEPCO)'s 345[kV] transmission line in 1998. And several feasible alternatives are composed for line reinforcement which can dissolve the bottle-neck.

• Journal of the Korean Society of Safety
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• v.26 no.4
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• pp.111-119
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• 2011

This study was designed to provide basic data applicable to fire investigation through consideration of combustion products and propose vulnerability of combustibles through analysis of $CO_2$ emission. In order to achieve these research objectives, characteristics of combustion products such as smoke release rate of each part(raw leaves, branches and barks), $CO_2$ emission and ash production were considered targeting on 6 oak species(Quercus variabilis Blume, Quercus aliena Blume, Quercus serrata, Quercus mongolica Fisch, Quercus dentata Sapling and Quercus acutissima) using cone calorimeter and smoke density tester. As a result, it was found that raw leaves release smoke more relatively than branches and barks, when they burn, and that Quercus variabilis Blume has the highest smoke density. Also, Quercus acutissima released CO and $CO_2$ which are respectively, 6.67 times and 1.43 times more than Quercus variabilis Blume with low $CO_2$ emission. In addition, branches released CO and $CO_2$ more relatively. There was a big difference in ash production among raw leaves(3.1 g), branches(10.5 g) and barks(16.43 g). It was identified that Quercus serrata produces ashes which are nearly 9.95 times more than Quercus variabilis Blume. It demonstrates that Quercus serrata contains relatively higher minerals and that Quercus variabilis Blume can leave lots of traces like stain and carbonization, as it releases smoke a lot and it's difficult to predict visibility, when a forest fire breaks out in its community area. It is also considered that smoke particles containing oil in the air leave strain on the surface of a tree, and that CO and $CO_2$ emission increases, when crown fire to burn branches breaks out.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.11 no.2
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• pp.59-67
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• 2007

Objectives: Pathogenesis treats cause of disease. Pyungweesan is pathogenic prescription of indigestion. This study researched for developing questionnaire of prescribing pyungweesan. Methods: Korean medical doctor classified the patients into two group, pyungweesan symptom group and non pyungweesan symptom group. After that, each group responsed to the questionnaire. We tested for both the reliability and validity of the questionnaire. For validity test, we compared the sum, average and standard deviation of 20 items of pyungweesan symptom group with those of non-pyungweesan symptom group through independent sample t-test, For reliability test, we computerized crohnbach's a value of the items. Results: The developed questionnaire showed remarkable reliability. (Cronbach's ${\alpha}$ =0.854) There were a significant differences on the sum of the 20 items and each 19 item's average and standard deviation, except 1 item; Do you have an irregular discharge from the womb? Conclusions: Based on the results of the above analysis, the korean medical doctor will make an effort to apply the pyungweesan questionnaire clinically. In the future, the additional research is needed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3426-3433
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• 2015

Three baggage allocation methods of passenger-baggage hybrid train in restricted railway transportation capacity including round conveyor system, vertical circulation system, and horizontal circulation system are presented. Loading/Unloading time is calculated based on the volume transported from Busan to Seoul via Daegu, Daejeon, and Osong with the parcel company P's logistics data. The horizontal circulation system shows less baggage volume capacity to be allocated and the maximum loading/unloading time with 434 secs. The vertical circulation system presents more loading time, but it shows best result with 408 secs. Loading/Unloading times are compared for each system and useful method is presented to improve transportation efficiency of the train.

• Congress of the korean instutite of fire investigation
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• 2011.04a
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• pp.102-116
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• 2011

With the spread of FMD and AI in the country livestock farmers have used lime(CaO) prevalently and due to incorrect storage lime served as a fire ignition source in a number of cases. As combined chemically with water, lime has exothermic reaction. Then In these experiments we want to know how exothermic reaction - caused by lime - acts as sources of fire ignition in any circumstances and conditions. So we have done experimental work of ignition temperature and ignition process in the artificial conditions as lime combined chemically with water. As a result, we have confirmed that lime could be flammable material sufficiently as a fire ignition source with the proper presence of heat and moisture conditions. If the lime served as sources of fire ignition, as identification techniques of fire scene, we must ascertain the existence of water, flammable material and Calcium Hydroxide($Ca(OH)_2$). We should take special precautions in order to prevent fire and educate the safe handling of lime to the manufacturer and agricultural cooperative's joint livestock farmers who product or use lime.

• The Korean Journal of Mycology
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• v.38 no.1
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• pp.80-82
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• 2010

Omphalotus japonicus is known to as a poisonous mushroom in East Asia, but Illudin S, bioluminescent compound, has been recently reported for an anticancer effect. The fungus is quite rare in natural condition in Korea. Therefore, we tried to cultivate in the mushroom on the sawdust cultivation to provide sufficient amount of mushroom for pharmaceutical study for the future. The mushroom could be harvested from all sawdust media used in this study, and the sawdust of Pinus densiflora was considered to be the best for mushroom cultivation with considering mushroom productivity and cultivation period. The mushroom was produced 43~80 g fresh weight per 600 g sawdust medium in average, and could be harvested one to three times during cultivation period.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.89-94
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• 2010

Plant pathogenic fungi are the most diverse and drastic causal agents of crop diseases threatening stable food production all over the world. Plant have evolved efficient innate immune system to scout and counterattack fungal invasion and pathogenic fungi also developed virulence system to nullify plant resistance machinery or signaling pathways and to propagate and dominate within their niche. A growing body of evidences suggests that post translational modifications (PTMs) and selective/nonselective degradations of proteins involved in virulence expression of plant pathogenic fungi and plant defense machinery should play pivotal roles during the compatible and incompatible interactions. This review elucidates recent investigations about the effects of PTMs and protein degradations on host defense and fungal pathogens' invasions.

• Radiation Oncology Journal
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• v.9 no.2
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• pp.343-350
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• 1991

The quasi-conformation therapy was performed to get a homogeneous dose distributions for irregeular shaped tumor lesion by using the arc moving beam and beam modifying filter which was made by cerrobend alloy($\rho$=9.4 g/cc) metal. In our dose calcuation programme, it was fundmentally based on Clarkson's method to calcuate the irregular multi-step block field in rotation therapy. In this study, the expected relative depth doses under multipartial attenuator agree well with measured data at same plane. The results of comparison the dose computation with that of TLD measurement are very closed within ${\pm}5\%$ uncertainties in the irradiation to phantom with quasi-comformation method. And it has shown that irregular typed multi-step filter can be applied to quasi-conformation therapy in high energy radiation plannings.