• Journal of Bio-Environment Control
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• v.3 no.1
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• pp.36-41
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• 1994

The major objective of this study is to develop a method of zone cooling during summer day using heat pump for year- round cultivation. The efficiency of cold water cooling and fog cooling was investigated. In order to prevent the occurrence of blossom - end rot in tomato, cooling was induced together with air flow of the fruit treatment as well as promoting air circulation in the plant treatment was induced. The following results were obtained : 1) The temperature in the cold water cooling district was 1$0^{\circ}C$ lower than greenhouse temperature and the temperature in the fo8 cooling district was about 5$^{\circ}C$ lower than the greenhouse. 2) Regardless of cooling method, the treatment of air flow on fruit did not affect the fruit but prevent blossom-end rot. There was 34.5% occurrence rate of blossom -end rot in non-air flow district of cold water cooling 54.5% in non-air flow district of fog cooling and 78% in fog circulation cooling district. The cooling efficiency using cold water cooling method induced enough cooling at critical temperature for growth and development and the occurrence of blossom -end rot was lower than fog cooling. Fog cooling in culture district with air circulation did not induce and difference in temperature but caused an Increase in humidity resulting in 24% increase in the occurrence of blossom-end rot. Thus the occurrence of blossom-end rot in tomato caused by environmental factors can be attributed more to humidity than to temperature.

• 한국해양학회지
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• v.4 no.2
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• pp.71-82
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• 1969

By use of the oceanographic data from 1932 to 1941 and from 1960 to 1967, the general properties of the cold water in the Korea Strait are discussed. This water characterized with temperatures 3-10$^{\circ}C$ and salinities 34.0-34.4 originates from the Japan Sea and begins to flow out in summer along the bottom about 8 to 18 miles southeast of Ulgi in Ulsan. It usually reaches the Pusan- Tsushima section and rarely to the west of the southernmost part of Tsushima. As it flows out, it shows rising trend along the coast of Korea and sometimes upwelling occurs in the vicinity of Ulsan. It seems that the cold water forms an under current along the bottom in summer and autumn in the western channel of the Korea Strait.

• Journal of Korean Medicine Rehabilitation
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• v.20 no.4
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• pp.51-56
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• 2010

Objectives and Methods : This study was performed to know about the reason of pain, the type of pain, etc. from "Somun(素問)" and "Yeongchu(靈樞)" of "Hwangjenaegyeong(黃帝內經)". And then we recognized the rational Korean medical physiotherapy about the pain control. Results : There was well described about the pain in "Hwangjenaegyeong(黃帝內經)". It was explained that the reason of pain was cold pathogenic factor one of the six exogenous pathogens. If the body was cold and qi-blood was lack of free flow, and the pain was occurred. Conclusions : According to above results, warming the meridian therapy is rational Korean medical physiotherapy about the pain control. An that gives positive effect about the pain control.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.4
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• pp.576-582
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• 1996

This work studies qualitative thermal characteristics of PCM cold storage medium container and its surrounding streams. Experimental parameters are initial PCM temperature and cold water flow rate. A mathematical modeling was establised to estimate temperature distribution and the cooling process. We found that the phase-change temperatures of PCM varies from 6 to $8^{\circ}C$ which is constant for other materials and that the dominant heat transfer resistance is that on the container side taking about 3/4 of the total resistance. The one dimensional mathematical model predicts experimental data quit well.

• Microbiology and Biotechnology Letters
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• v.46 no.2
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• pp.111-113
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• 2018

In this study, purification of cold-adapted protease from Janthinobacterium sp. was investigated. First, using gradient precipitation, protease was confirmed to be deposited in the 30-80% range of ammonium sulfate. Next, DEAE-Sepharose column was used for the binding of the protease under various conditions. The optimal binding condition was found to be pH 8.5 and flow rate of 30 ml/h. Under the optimal condition, the protease was purified with 29% recovery yield. This result can be useful for the purification of other cold-adapted protein.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2234-2244
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• 1994

A process sequence of multi-operation cold forging for actual application in industry is designed with the rigid-plastic finite element method to form a constant velocity joint housing(CVJ housing). The material flow during the CVJ housing forming is axisymmetric until the final forging process for forming of ball grooves. This study treats the deformation as an axisymmetric case. The main objective of the process sequence design is to obtain preforms which satisfy the design criteria of near-net-shape product requiring less machining after forming. The process sequence design also investigates velocity distributions, effective strain distributions and forging loads, which are useful information in the real process design.

• Journal of the Korean Society for Precision Engineering
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• v.7 no.4
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• pp.140-148
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• 1990

A mathemetical medel has been developed for the purpose of estimating the rolling force required for computer control of cold strip mills. The model consists of equations of rolling force. flow stress. friction coefficient and tension. By applying the model to a 6-High cold tandem mill, the computer simulation is then been possible for all kinds of steels except stainless steel and the effectiveness of the model has been confirmed in the practice.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.645-650
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• 2003

The purpose of this study is to provide the optimum mix design of cold weather concrete to be placed at the foundation structures in substation. The basic performance tests including slump and slump flow, air content, compressive strength and freezing & thawing resistance were conducted for cold weather concrete by varying with W/C ratios such as 40%, 50% and 60% and air contents such as 3%, 4%, 5% and 6%. The effect on durability of concrete corresponding to the increasing amount of air content and W/C ratio was evaluated and the optimum mix design was recommended. From this study, the concrete mix design containing 6% of air content and 45% of W/C ratio is recommended for the foundation concrete of substation.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.473-477
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• 2000

The experimental study of die-sinking electrical discharge machining(EDM) was conducted for Cold Die Alloy Steel of SKD-11 with rotary electrode according to the peak current of 11A, 15A and 19A, and the duty factor of 0.24, 0.45. dielectric fluid flow through the electrode inside according to the change of electrode internal diameter during the EDM working. Material removal rate(MRR) was increased with flushing & rotation of electrode at the condition for the peak current of 15A, 19a but the MRR is decreased at the flushing only. The more surface roughness was obtained for the case of the flushing & rotation under the peak current of 19A.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.10a
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• pp.338-341
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• 2004

The dimension of forged part is different with the die dimension by the various effects, such as, elastic deformation and thermal effect. And, the difference amounts are not same according to the forging conditions, for example, forging mode, flow stress, etc. Therefore, the use of FEA is effective to predict and update the required die dimension. However, the variables for FE simulation are also as many as variables in the experiment. The variables give very much effect to the accuracy of FE results. At first, the material model is very deeply affected to the estimated dimension of forged part. And the considering of loading and ejecting stages is also important to increase the dimensional accuracy. The experiment and FEA are performed to investigate the dimensional changes and accuracy in cold forging. Two types of upsetting are used to survey the effects of forging mode and stages.