• 한국분말재료학회지
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• 제19권2호
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• pp.110-116
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• 2012

This study investigated the effects of annealing environment for the densification and purification properties of pure titanium coating layer manufactured by cold spraying. The annealing was conducted at $600^{\circ}C$/1 h and three kinds of environments of vacuum, Ar gas, and $5%H_2+Ar$ mixture gas were controlled. Cold sprayed Ti coating layer (as sprayed) represented 6.7% of porosity and 228 HV of hardness, showing elongated particle shapes (severe plastic deformation) perpendicular to injection direction. Regardless of gas environments, all thermally heat treated coating layers consisted of pure ${\alpha}$-Ti and minimal oxide. Vacuum environment during heat treatment represented superior densification properties (3.8% porosity, 156.7 HV) to those of Ar gas (5.3%, 144.5 HV) and $5%H_2+Ar$ mixture gas (5.5%, 153.1 HV). From the results of phase analysis (XRD, EPMA, SEM, EDS), it was found that the vacuum environment during heat treatment could be effective for reducing oxide contents (purification) in the Ti coating layer. The characteristic of microstructural evolution with heat treatment was found to be different at three different gas environments. The controlling method for improving densification and purification in the cold sprayed Ti coating material was also discussed.

• Journal of Microbiology and Biotechnology
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• 제25권5호
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• pp.569-578
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• 2015

Cold water paddy field soils are relatively unproductive, but can be ameliorated by supplementing with inorganic fertilizer from animal waste-based composts. The yield of two rice cultivars was significantly raised by providing either chicken manure or cow dung-based compost. The application of these composts raised the soil pH as well as both the total nitrogen and ammonium nitrogen content, which improved the soil's fertility and raised its nitrification potential. The composts had a measurable effect on the abundance of nitrogencycling-related soil microbes, as measured by estimating the copy number of various bacterial and archaeal genes using quantitative real-time PCR. The abundance of ammonia oxidizing archaea and bacteria was markedly encouraged by the application of chicken manure-based compost. Supplementation with the composts helped promote the availability of soil nitrogen in the cold water paddy field, thereby improving the soil's productivity and increasing the yield of the rice crop.

• 대한한의학방제학회지
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• 제14권1호
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• pp.184-191
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• 2006

Cold Urticaria and Cholinergic Urticaria are considered to be distinct disorders in which mediator release and hives can be induced by different stimulti. While neither cold Urticaria nor cholinergic Urticaria is rare, it is unusual to see both disorders occurring in the same patient. Also, our case presents atypical urtication to cold exposure. similar to classic cholinergic Urticaria lesions, called ‘cold-induced cholinergic urticaria’. a case of It lives from as usual as cold as ice environment and When entering into the warm place, the patient minute when the urticaria appears cold - induced cholinergic Urticaria it suspects, The sasang constitution which will reach the result which it demonstrates medically it got the effect which considers it reports.

• 한국수소및신에너지학회논문집
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• 제31권1호
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• pp.33-40
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• 2020

As hydrogen utilization becomes more active recently, a large amount of hydrogen should be supplied safely. Among the three supply methods, liquefied hydrogen, which is an optimal method of storage and transportation convenience and high safety, has a low temperature of -253℃, which is complicated by the liquefaction process and consumes a lot of electricity, resulting in high operating costs. In order to reduce the electrical energy required for liquefaction and to raise the efficiency, hydrogen is cooled by using a mixed refrigerant in a precooling step. The electricity required for the precooling process of the mixed refrigerant can be reduced by using the cold energy of LNG. Actually, LNG cold energy is used in refrigeration warehouse and air liquefaction separation process, and a lot of power reduction is achieved. The purpose of this study is to replace the electric power by using LNG cold energy instead of the electric air-cooler to lower the temperature of the hydrogen and refrigerant that are increased due to the compression in the hydrogen liquefaction process. The required energy was obtained by simulating mixed refrigerant (MR) hydrogen liquefaction system with LNG cold heat and electric system. In addition, the power replacement rate of the electric process were obtained with the pressure, the temperature of LNG, the rate of latent heat utilization, and the hydrogen liquefaction capacity, Therefore, optimization of the hydrogen liquefaction system using LNG cold energy was carried out.

• Ocean Science Journal
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• 제41권4호
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• pp.227-234
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• 2006

Year-to-year variation of bottom cold waters around the Korea Strait was investigated based on bottom temperatures measured by submarine telephone cable between Pusan, Korea and Hamada, Japan from 1982 to 1992. The characteristics of bottom temperatures could be divided into three different groups: the Korean side, the middle, and the Japanese side. Temperature drops in summer appeared in all the three regions implying the intrusion of cold waters into the Korea Strait. Significant decreases in the Korean side were observed in 1983, 1986, 1990, 1991, and 1992 when bottom temperatures were high in the middle. In contrast, bottom temperatures significantly decreased in the middle in 1985, 1988, and 1989 when the temperature drops in the Korean side were relatively small. This tendency for a negative relationship was also shown in the second mode of an EOF analysis. In the years when bottom temperatures significantly decrease din the Korean side, the cold water along the east coast of Korea expanded offshore and its temperature was low. On the contrary, cold water in the southern region of the Ulleung Basin developed in the years when bottom temperatures decreased considerably in the middle.

• 대한기계학회논문집A
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• 제27권6호
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• pp.1007-1013
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• 2003

As environmental restriction kas continuously become more strict, machining technology has emphasized on development of environment-friendly technology. In cutting technology, it has been well recognized that cutting fluids might have undesirable effects on workers health and working environment. In this study, compressed cold air was used as a replacement for conventional cutting fluids. The cooling effect on cutting tool was analyzed using the finite element method and the computational fluid dynamics. This study focused on the temperature simulation of cutting tool by real flow analysis of cold air. The maximum flow rate and the minimum temperature of compressed cold air are 300ι/min and -30$^{\circ}C$ respectively. To compare the simulation and experimental results, inner temperature of the cutting tool was measured with the thermocouple embedded in the insert. The results show that the analysis of cutting temperature using FEM and CFD is resonable, and the replacement of cutting fluid with cold air is available.

• 한국의류산업학회지
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• 제1권1호
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• pp.69-73
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• 1999

Korean and Japanese, both people have a lot of similarity and complexity in terms of physical constitution and culture. This study might be the first implementation that tries to figure out constitutional differences of both people in scientific way. In this study, subjects were from each country, had been exposed $5^{\circ}C$ environment wearing each country's traditional costume- so called Hanbok and Kimono- and all through this experiment we'd compared physiological responses and analyzed differences of cold response go with their own clothing culture. We've obtained following results: Korean had kept maintaining low mean skin temperature basically in cold circumstance, compared with Japanese, have stronger cold tolerance. However, there's no significant difference between Korean and Japanese. Owing to huge influence of wearing other country's traditional costume itself even makes differences of rectal temperature in a cold environment. In addition, in a period of time that wearing other country's traditional costume, thermal sensation would be different according to exposed surrounding temperature.

• 한국식품위생안전성학회지
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• 제36권4호
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• pp.342-346
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• 2021

최근 원액상태로 장시간 보관이 용이하고 특유의 향을 유지할 수 있는 콜드브루커피가 남녀노소에게 크게 인기를 얻음에 따라 커피판매업체의 규모와 수가 증가하고 있으며, 명절 선물용으로도 각광을 받고 있다. 콜드브루커피는 차가운 물로 장시간 추출한 커피이므로 세균에 노출될 가능성이 크다. 따라서 본 연구는 시중판매되고 있는 콜드브루커피의 안전성을 조사하여 소비자에게 올바른 정보와 건강한 먹거리를 제공하고자 하였다. 총 75건의 콜드브루커피를 대상으로 식품공전 액상커피의 규격기준(세균수, 대장균군)과 식중독균 9종 및 카페인 함량검사를 실시하였다. 조사한 결과 온라인에서 구매한 9개 제품의 세균수가 규격기준을 크게 초과하여 검출되었으며, 대장균군 및 식중독균 9종은 검출되지 않았다. 또한 조사한 콜드브루 제품의 평균 카페인 함량은 1.6 mg/mL(240 mL 제품의 경우 카페인 384 mg 함유)이며, 카페인 과다 섭취 시 불면증, 신경과민 등 부정적인 작용들이 존재하므로 성인 기준으로 카페인 최대 일일섭취권고량 400 mg/day을 초과하지 않도록 주의가 필요한 것으로 나타났다.

• Journal of Ecology and Environment
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• 제34권3호
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• pp.251-257
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• 2011

The purpose of this study was to investigate the acclimation responses of Tamarix chinensis to cold stress. We evaluated the acclimation responses by measuring biomass, daily elongation rate, chlorophyll content, and total soluble carbohydrate content. The plant samples comprised leaves from seedlings of 2 different ages (8 and 12 weeks); the leaves were collected 0, 2, and 4 weeks after cold treatment. We found that the cold-treated samples showed reduced daily elongation rates and chlorophyll content. Further, these samples showed more than 8-fold increase in the total soluble carbohydrate content. However, the seedling ages did not have a significant influence on the growth of cold-treated seedlings. On the basis of these findings, we can conclude that T. chinensis seedlings aged less than 1 year old show acclimation to cold stress by accumulating soluble carbohydrates. This study may help us understand how T. chinensis seedlings acclimatize to their first cold season.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.1067-1070
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• 2009

유통 물류 시스템에서 온도 제어를 비롯한 환경정보의 제어는 매우 중요하다. 제품의 온도정보관리뿐만 아니라 환경정보에 대한 실시간 관리를 위한 Smart Cold Chain Management(SCCM) 시스템에서는 유통/물류시스템에서 사용하는 태그 정보뿐만 아니라 다양한 센서 정보를 실시간으로 통합 관리하여야 한다. 그러나 다양한 종류의 태그 정보를 통합 관리할 뿐만 아니라 온도, 습도, 위치데이터등과 같은 다양한 환경 정보를 통합 관리하기 위해서는 표준화된 코드 체계가 필요하다. 이 논문에서는 SCCM시스템에서 적용될 수 있는 표준 코드 체계를 제시한다.