• 한국축산시설환경학회지
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• 제21권2호
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• pp.47-54
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• 2015

Climate change has directly impacted environmentally dependent first industry. The changes of amount and frequency of precipitation have caused unstable drinking water supply for grassland and feed crop, and have changed the variety of grassland and feed crop. Rising temperature has caused heat stress on livestock, which has impacted feed intake and livestock products, and also has threatened to the health of livestock by widening the range of sources of diseases. In order for livestock industry to confront climate change, new technology development for climate change adaptation and measures of greenhouse gas mitigation are essential. Agroforestry is the one of alternative measures to mitigate greenhouse gases and to adapt to climate change. Agroforestry is the way rearing livestock and cultivating plants in forest, which is suitable to Korea where mountain area is over 68%. Feedstock such as maize, soybean, rice, and grass grown by agroforestry would decrease feed cost. Agroforestry will decrease heat stress of livestock during hot weather and will be possible to pasture, which increases livestock welfare.

• 한국환경복원기술학회지
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• 제16권5호
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• pp.49-57
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• 2013

This study was carried out to analysis change of distribution and habitat location environment of Korean Fir which is typically vulnerable species by the climate change in Mt. Jiri and Halla. Korean Fir was decreased 18% during 27 year since year 1981, Mt. Halla was 34% during 15 years since year 1988. In the same periods, Temperature change was increased from 8.56 to $9.36^{\circ}C$, from 11.2 to $12.1^{\circ}C$. Distribution changes by the elevation showed higher change ratio 1,400~1,600m in Mt. Jiri and 1,200~1,900m in Mt. Halla. Changes of Korean Fir each slope aspects was high $180{\sim}360^{\circ}$ in Mt. Jiri, $45^{\circ}$ in Mt. Halla. In slope was $30^{\circ}$ in Mt. Jiri and $20^{\circ}$ in Mt. Halla. Changes by reliefs was 12 in Mt. Jiri, 0 or 15 in Mt. Halla, and Sites of Korean Fir was convex slopes both of two areas. Changes by soils was in the good drainage textures.

• E2M - 전기 전자와 첨단 소재
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• 제8권2호
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• pp.229-236
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• 1995

Multimedia has created a system environment that needs a combination of diverse peripherals, faster I/O, and easier configuration. The sheer volume of data one can expect with multimedia hardware and applications storage systems of higher capacity and faster data transfer rate. Unlike the magneto-optical(MO)disk technology which uses bias magnetic field in writing, both the reading and the writing in the phase change (PC) technology are performed only by laser light. In PC optical media, an active layer is reversibly converted between amorphous state and crystalline state by changing irradiation conditions of focused laser beam. Thus, as compared with MO disk, the PC disk has such great advantages that signals can be reproduced by change of reflectance of laser beams in the same manner as the compact disc. The reflectivity of a phase-change spot can be altered in a single pass under the head only through modulation of laser power. The principles and the current status of phase-change optical recording media combined with possible applications are discussed in the present article.

• 설비공학논문집
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• 제25권9호
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• pp.477-483
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• 2013

A numerical analysis of solid-liquid phase change was performed on a heat transfer module which consisted of circulating water path (BRINE), heat transfer plate (HTP) and phase change material (PCM) layers, such as high temperature PCM (HPCM, $78{\sim}79^{\circ}C$) and low temperature PCM (LPCM, $28{\sim}29^{\circ}C$). There were five arrangements, consisting of BRINE, HTP, LPCM and HPCM layers in the heat transfer module. The time and heat transfer rate for melting/solidification was compared to their arrangements, against each other. As results, the numerical time without convection was longer than the experimental one for melting/solidification. Moreover, the melting/solidification with the BRINE I-LPCM-BRINE II-HPCM arrangement was faster(10 hours) than the others; HPCM-BRINE-LPCM, BRINE I-HPCM-LPCM-BRINE II one.

• 한국생산제조학회지
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• 제8권5호
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• pp.90-95
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• 1999

Chucking for workpieces is very important for productivity and efficiency in lathe operations. In point of productivity top jaws of the chuck should be changed as quickly as possible in order to reduce idle times wherever workpieces are regripped. A quick change power chuck which can change top jaws quickly by using a jaw change handle without any assembly/disassembly processes of screws is analyzed for this study. strength and stiffness of top jaws by centrifugal force are considered for the design. Structural analysis for the chuck is executed and the finite element method is introduced using MSC/NASTRAN software. Also, the performance of the chuck is evaluated by experiments.

• Coupled systems mechanics
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• 제5권4호
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• pp.305-314
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• 2016

We utilize first-principles calculations within density-functional theory to investigate the possibility of strain engineering in the tuning of the band structure of two-dimensional $MoS_2$. We find that the band structure of $MoS_2$ monolayers transits from direct to indirect when mechanical strain is applied. In addition, we discuss the change in the band gap energy and the critical stains for the direct-to-indirect transition under various strains such as uniaxial, biaxial, and pure shear. Biaxial strain causes a larger change, and the pure shear stain causes a small change in the electronic band structure of the $MoS_2$ monolayer. We observe that the change in the interaction between molecular orbitals due to the mechanical strain alters the band gap type and energy.

• Journal of Advanced Marine Engineering and Technology
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• 제28권8호
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• pp.1225-1238
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• 2004

The present study has been performed for obtaining the melting heat transfer enhancement characteristics of water mixture slurries of plural microcapsules having different diameters encapsulated with solid-liquid phase change material(PCM) flowing in a pipe heated under a constant wall heat flux condition. In the turbulent flow region, the friction factor of the present PCM slurry was to be lower than that of only water flow due to the drag reducing effect of the PCM slurry. The heat transfer coefficient of the PCM slurry flow in the pipe was increased by both effects of latent heat involved in phase change process and microconvection around plural microcapsules with different diameters. The experimental results revealed that the average heat transfer coefficient of the PCM slurry flow was about 2～2.8 times greater than that of a single phase of water.

• 한국IT서비스학회지
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• 제6권2호
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• pp.35-47
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• 2007

The purpose of this thesis is to analyze the success factors of ERP system in corporations and to know what is different in the factors depending on organizational culture and size. Considering there are various results from introduction of the same information technology(IT), it is implied that organizational characteristics make a difference. In this thesis we did factor analysis and multiple regression about the factors based on the previous studies and analyzed the priorities depending on organizational culture and size. The results show that mechanistic organization has key success factors of work process change, project team abilities, and determination of CEO while organic organization has those of work process change and project team abilities. Plus bigger sized organization has success factors of work process change, project team abilities, and determination of CEO while small sized organization has those of work process change and project team abilities.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2000년도 춘계학술대회 논문집
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• pp.150-151
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• 2000

Some chromophores that can undergo a pronouncend colour change when acted upon an extenal agency, such as light, heat, pH, or chemical agents, have many potential applicationa as functional dyes. They may be used as indicators, optical sensors, biochemical probes, optical and thermal recording materials. The results will investigate donor-acceptor chromophores which have the potential for such colour change processes. In particular, cross-conjugated donor-acceptor chormophores, analogous to indigo and squarylium-type chromophores, will be examined for pH sensitizing and for their oxidation-reduction colour change behaviour.

• 한국환경복원기술학회지
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• 제10권6호
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• pp.110-119
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• 2007

This study's objects are to predict distribution and to assess vulnerability of sub-alpine vegetations in the Korean peninsula for climate change using various climate models. This study validates relationship between sub-alpine vegetations and environmental factors using Pearson correlation analysis. Then, the future distribution of sub-alpine vegetations are predicted by a logistic regression. The major findings in this study are; First, spring mean temperature (March-May), total precipitation, elevation and warmth index are highly influencing factors to the distribution of sub-alpine vegetations. Second, the sub-alpine vegetations will be disappeared in South Korea and concentrated around Baekdu Mountain in North Korea. North Korea is predicted to have serious impact of climate change because temperature will be increased higher than in South Korea. The study findings concluded that the assessment of the future vulnerability of sub-alpine vegetations to climate change are significant.