• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.652-655
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• 2005

Considering the fact that more than $97\%$ of fossil energy resources such as oil and natural gas needed in Korea rely on import, primary concern of the national economy is to secure future energy sources. Gas hydrates. which is non-conventional types of natural gas, distribute worldwide, especially in marine and permafrost Gas hydrates draw great attention recently as a new clean energy resources substituting conventional oil gas due to its presumed huge amount of volume reaching 10 trillion tons of gas and environmentally friendly characteristics. Results of preliminary survey by Korea Gas Corporation (KOGAS) and Korea Institute of Geoscience and Mineral Resources (KIGAM) showed that gas hydrates can be present in deep sea over 1,000m water depth in the East Sea. Gas hydrates can contribute to the rapidly increasing consumption of natural gas in Korea and achieve the self-support target by 2010 with $30\%$ of total natural gas demand. This study presents the potentialities and development prospects of gas hydrate as a future energy source.

• 패션비즈니스
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• 제9권6호
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• pp.29-38
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• 2005

Natural dyes have attracted the worldwide attention because of its environmental advantage over synthetic dyes. However, most of natural dyes are expensive for mass production, strongly season and source dependent, and hard to store. In this study, coffee waste were used as natural dye to create beautiful colors. Coffee waste is inexpensive and easy to store, and provides a comparatively regular quality regardless of seasonand source. The effects of mordant agent concentration and mordanting temperature on dyeing efficiency of silk fabrics were investigated. Coffee extract dyed silk showed brilliant colors, and the colors were different with the kind of mordants. Cu, Sn, and Al mordanted silks showed golden yellow with subtle change of hue and value, while Fe mordanted silk showed a brownish green color. The increase in mordant concentration did not always increase the dyeability, and 0.5% o.w.f. mordant concentration was enough to get a satifactory result. Mordanting temperature also had little effect on the dyeability in case of Al, Cu, and Sn mordanted fabrics. Only Fe mordanted fabrics showed a better dyeability in the increase in mordating temperature. Coffee extract dyeing is an effective way using waste as resource and can create brilliant colors with minimal amount of mordant and under mild mordanting condition.

• 한국의상디자인학회지
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• 제15권1호
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• pp.91-109
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• 2013

The main objective of this research was to understand the latest trends of natural print design through the quantitative & qualitative analysis of fashion appeared in contemporary female collections. The research criteria was defined as 3 seasons from 2011 S/S to 2012 S/S. Data collection of 726 was done through review of 'pr$\hat{e}$t-$\grave{a}$-porter Collections' of three major fashion cities; Paris, Milan and NY. Statistical analysis of frequency with chi-square test was conducted. Also qualitative interpretation of natural print design' characteristics was completed. The main findings were as follows.; The average occurrence rate of natural print design from 2011SS to 2012 SS in three collections were 6.4% in Milan 6.4%, 5.5% in Paris and 6.8% in N.Y. The five source types of natural prints in contemporary women's fashion collections were identified and the order of their appearance were as follows: flowers, plants, animals, insects & marine organisms and compound one. The plant prints were expressed by stylized or realistic touch. Flower patterns showed more variables than plants, however, there were no big difference in their image and major characteristics. The animal prints demonstrated two aspects. First one used typical animal print of fur or skin, but the other one draw the animal figure like paintings. The compound source type presented the most interesting and fresh pattern design ideas. In the insects & marine organisms, mainly butterfly and seashell & starfish, etc. appeared as real shapes or sometimes were stylized.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.497-502
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• 2001

Three-dimensional natural convection from a discrete flush-mounted circular heat source on the bottom of a cubic enclosure was studied by using a holographic interferometric tomography. The heat source was located at the off-center of the bottom plate so that three-dimensional temperature field can be achieved. A set of multidirectional holographic interferogram was recorded by employing a double-reference beam, double-exposure holographic technique in order to eventually reconstruct the temperature fields. The recorded interferometric data appear good enough to be further processed to extract optical pathlength data from them and finally reconstruct the temperature fields. A complete analysis of the temperature fields including the field reconstructions and comparison with thermocouple measurements is underway and will be reported shortly.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1609-1614
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• 2003

In this study, a practical holographic interferometric tomography system, which is instantaneous and non-contact for measuring three dimensional flow field, was developed. The system consists of holographic recording/reconstruction system, fringe analysis code and computational tomography code and it is developed with Gill environment for general users. The developed system was applied to three-dimensional natural convection from a discrete flush-mounted circular heat source on the bottom of a cubic enclosure. The heat source was located at the off-center of the bottom plate so that three-dimensional temperature field can be achieved. A set of multi-directional holographic interferograms was recorded by employing a double-reference beam, double-exposure holographic technique. Optical pathlength data were extracted from the recorded interferometric data and finally three dimensional temperature field inside the cube was reconstructed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.487-490
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• 2002

The real chip and similarity model were used to investigate the thermal behavior and velocity distribution of air from the heat source with the location and the amount of heat experimentally and numerically, and compared. The heat generated in the block is not cooled by convection and show the high temperature by the stagnation of heat flow. After maintaining the high temperature of block by the natural convection, the sudden drop of temperature with the air flow was shown in the channel but the decreasing rate was small with the time. The inward block was effected by infinitesimal air flow generated between block and channel and outward block was effected by the entry condition.

• 한국환경보건학회지
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• 제18권2호
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• pp.92-101
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• 1992

Halogen substituted-phenol and analog phenol degrading strains were identified as Aeromonas, Moraxella, and Flavobacterium genus. Optimal degrading condition was generally 50~100 $\mu$M substituted-phenol as carbon source, $NH_4NO_3$ as nitrogen source, 30$\circ$C , and initial pH 7.2. $\rho$-Chlorophenol degrading strain of Aeromonas sp. C4 had biodegradability to the various substituted-phenols. Flavobacterium sp. M9 had substrate specificity to methyl substituted-function. Catechol was cleavaged by catechol 1, 2-dioxygenase in Aeromonas sp. C4, Moraxella sp. N7, and Flavobacterium sp. M9.

• 한국환경보건학회지
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• 제28권2호
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• pp.11-22
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• 2002

This study analyzes the river system and water quality conditions of Bukchun in order to establish a basic plan for Preparing a natural learning and experimental area of environmental ecosystem in Bukchun, Gyeongju. It also tries to establish an integrated plan for water management of Bukchun stream based on water contaminants. In addition, after analysing the water quality at 13 points during the non-rainy season, the effluent of municipal wastewater was of relatively better quality with I ~ II grade, below the water quality standard of the river, except in points near Samsung apartments. However, analysing the Hyeongsangang and the effluent of Bomunho and Duckdongdam in rainy season, the water quality was II ~ III grade according to environmental standard. The water Quality of those samples was strongly dependent of non-point source.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.322-327
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• 2000

Natural convection heat transfer in an enclosure with an opening in the right vertical wall and a heat source at the bottom surface is investigated using a holographic interferometric technique. The effects of the opening length, divider length attached to the top wall, and heater temperature on the temperature distribution are examined. The openging length as well as the divider length greatly affects the degree of inflow and outflow of air. With a small opening, the opening doesn't affect much the upward warm air flow resulting in the symmetric temperature distribution. On the other hand, with the increase of the opening length, the inward cold flow moves the upward flow to the left direction. With the increase of the divider length, temperature in the lower region of enclosure becomes higher for the small opening and lower for the large opening.

• Applied Science and Convergence Technology
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• 제26권5호
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• pp.129-132
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• 2017

We report a chemical vapor deposition approach and optimized growth condition to the synthesis of single layer molybdenum disulfide ($MoS_2$). Obtaining large grain size with continuous $MoS_2$ atomically thin films is highly responsible to the growth distance between molybdenum trioxide source and receiving silicon substrate. Experimental results indicate that triangular shape $MoS_2$ grain size could be enlarged up to > 80um with the precisely controlled the source-to-substrate distance under 7.5 mm. Furthermore, we demonstrate fabrication of a memory device by employing poly(methyl methacrylate) (PMMA) as insulating layer. The fabricated devices have a PMMA-$MoS_2$/metal configuration and exhibit a bistable resistance switching behavior with high/low-current ratio around $10^3$.