• Journal of Microbiology and Biotechnology
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• 제22권6호
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• pp.806-813
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• 2012

Adipocyte differentiation is strongly associated with obesity, which causes metabolic disorders. In this study, we investigated the inhibitory effects of widdrol on 3T3-L1 preadipocyte growth and differentiation. Widdrol decreased lipid droplet accumulation and down-regulated adipogenic transcription factors such as C/$EBP{\alpha}$, C/$EBP{\beta}$, and $PPAR{\gamma}$. Widdrol blocked preadipocyte proliferation and differentiation through the inhibition of mitotic clonal expansion, which was accompanied by the failure of degradation of p21, a cyclin-dependent kinase inhibitor. Cell-cycle analysis clearly indicated that widdrol actively induces cell-cycle arrest at the G1-S phage transition, causing cells to remain in the preadipocyte state. Moreover, widdrol increased p21 expression and inhibited Rb phosphorylation in preadipocyte incubated in a hormone medium. Therefore, these findings clearly suggest that widdrol blocks preadipocyte growth and differentiation through the inhibition of mitotic clonal expansion by p21-and Rb-dependent G1 arrest and can be developed as a potent anti-adipogenic agent for reducing obesity.

• The Korean Journal of Ecology
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• 제12권4호
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• pp.219-236
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• 1989

The effect of salinity on the seed germination and seedling growth of Pinus densiflora for. erecta Uyeki were studied under the controlled conditions in the growth chamber. The seeds were sorted into three classes in weight such as large ($15.49\pm$1.63mg), medium($10.61\pm$1.38mg), and small ($6.57\pm$1.33mg) to determine the role of seed weight in germination and seedling growth of the pine. Polymorphic seeds of the pine were germinated an salinity range of 0 to 1.5% NaCl under various temperature ($10^{\circ}$ $-25^{\circ}$ with $5^{\circ}$C interval of constant temperature, and $10^{\circ}$ $-20^{\circ}$C, $15^{\circ}$ $-25^{\circ}$C of alternating temperature) in order to determine their germinability and seeding growth. In control plot, there was little difference of germination percentage among the seed weight classes, but in saline plot, the larger seeds generally had a higher percentage and rate of germination. There occurred synergistic interaction between salinity and temperature in the germination and the increase of temperature enhanced germination of seeds at the same salinity level. Alternating temperature regimes of $15^{\circ}$-$25^{\circ}$C yielded maximum germination and no germination was occurred at $10^{\circ}C$. The germination at alternating temperature showed higher germination percentage than at constant temperature. The percentage and of germination decreased drastically with increased salinity level to 1.00%; no germination was occurred at 1.50% salinity level. The growth fo sddelings from larger seeds was better than that of smaller seeds at the same salinity and temperature. The hypocotyl and radicle were more sensitive than cotyledon to the increased salinity stress.

• Journal of the Korean Geotechnical Society
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• 제20권9호
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• pp.91-103
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• 2004

A series of shaking table model tests were performed to verify the validity of similitude law, which is suggested by lai (1989) to simulate the dynamic behavior of soil-fluid-structure system for is shaking table tests. In the tests, the similitude law suggested by lai was applied to determine the length and the time scaling factors. Also, the steady state concept was used in determining the density of model backfill soil, which is a key factor in simulating the development of excess pore pressure during shaking. The similitude law was verified by checking whether three different sizes of quay walls show the identical behavior or not. The similar responses of acceleration, excess pore pressure and horizontal displacement of walls were obtained far the small and large models. However, the medium model showed larger responses than those of the small and large models because of the resonance between the frequency of input acceleration and the natural frequency of the wall system. In addition, the vertical displacement and rotational angle of the walls became larger with the increase of model size.

• Journal of the Korean Institute of Landscape Architecture
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• 제27권5호
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• pp.12-24
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• 2000

This study seeks to find an approach tool that allows to consider both ecological and visual aspect in developing an ecological space. Main objective of this study is to develop a planting design method in consideration of correlation between high visual preference and ecological diversity. To this end, an integrated method based on visual design principles and landscape ecological principles was developed first. Then study areas of 20 natural areas and 10 urban areas were selected to survey and analyze visual preference and ecological diversity. The result showed that scale is an element that has the greatest impact on visual preference. In areas with high ecological diversity, scale and connectivity had the biggest impact. In order to have a planting design desirable visually and ecologically based on these factors, it may be divided into following three issues.(1) In oder to increase ecological diversity in areas with strong visual preference, a priority should be given to introduce techniques promoting harmony among dominant species of various scales and other species. At the same time, there should be efforts to secure connectivity. (2) To improve visual preferences in areas with high ecological diversity, close-range, medium-range, and distant landscapes should be ensured by aligning colors and connectivity of various scales with other factors. (3) Also, a target area should be developed into a visually preferred and ecologically sound area by supplementing form and interlocking issues and identifying the spirit of the place. This study offers a way to improve visual preference and promote ecological diversity indeveloping ecological parks for the future. In landscape planning and design, it is important to secure various scales and connectivity as high-priority principles.

• Korean Chemical Engineering Research
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• 제46권4호
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• pp.647-659
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• 2008

Colloids are a heterogeneous system in which particles of a few nanometers to hundreds micrometers in size are finely dispersed in liquid medium, but show homogeneous properties in macroscopic scale. They have attracted much attention not only as model systems of natural atomic and molecular self-assembled structures but also as novel structural materials of practical applications in a wide range of areas. In particular, recent advances in colloidal science have focused on nano-bio materials and devices which are essential for drug discovery and delivery, diagnostics and biomedical applications. In this review, first we introduce nano-bio colloidal systems and surface modification of colloidal particles which creates various functional groups. Then, various methods of fabrication of colloidal particles using holographic lithography, microfluidics and virus templates are discussed in detail. Finally, various applications of colloids in metal inks, three-dimensional photonic crystals and two-dimensional nanopatterns are also reviewed as representative potential applications.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 한국추진공학회 2010년도 제35회 추계학술대회논문집
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• pp.658-663
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• 2010

With petroleum reserves dwindling, interest has been increasing worldwide in Fischer-Tropsch synthesis (FT) as a method of producing synthetic liquid fuels and chemicals from coal, natural gas or biomass. In general, FT synthesis is operated through the gas phase fixed-bed reaction system. Recently, there are lots of study in supercritical fluid due to unique characteristics such as the quick diffusion of reactant gas, effective removal of reaction heat, and the in-situ extraction of high molecular weight hydrocarbon, such as wax. In this study, our major aim is to obtain a deeper insight into the effect of the type of support on the reaction performance over a supported cobalt catalyst in a fixed bed reactor.

• The Research Journal of the Costume Culture
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• 제19권4호
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• pp.751-765
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• 2011

The purpose of this study is to apply the Trencadis images in Antony Gaudi's work to a design motive and thus provide a new concept for a knitwear design by combining double-knitted fabrics with patchwork applique, taping, stitching and quilting. This study examines the bibliographic text and precedent research related to Antony Gaudi and his works, and analyzes the historical background and formative and stylistic characteristics of Trencadis as it appeared in Gaudi's architectural works. Also this study also examines the characteristics of knitwear and knitting theory while exploring the formative elements and the combined techniques used in modern knitwear design through fashion magazines, medium images, and online sources. The results are as follows: First, Gaudi's work that applies a Trencadis technique has the characteristic of being creative, organic, and environmentally friendly. And in addition, its colorfulness inspires modern fashion design. Second, computerized knitting has been practiced in various ways and the fabrics knitted by both double-knitting jacquard and computerized knitting machines provide a new direction the creation of knitwear. A computerized knitting machine is especially effective for pictorial expression, and is suitable for showing the natural curve of the human body due to its sophistication. Third, as a result of applying a combined technique to the knitting of various fabrics, a combined or fusion design, which is a recent megatrend, is very effective for the design of knitwear while increasing its aesthetic value. Moreover, utilizing techniques that combine patchwork applique, taping, stitching and quilting will create higher value in knitwear. Lastly, with a project of applying combined techniques in the creation of knitwear, designers can become much more creative while taking their imagination much further.

• Journal of the Korean Society of Propulsion Engineers
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• 제4권3호
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• pp.29-37
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• 2000

Because the previous design procedure for the composite wind turbine blade structure using trial and error method takes long time, a improved design procedure by using the program based on classical laminate theory was proposed to reduce the inefficient element. According to the improved design procedure, limitation of strains, stresses and displacements specified by international standard specification IEC1400-1 for the composite wind turbine blade were applied to sizing the structural configuration by using the rule of mixture and the principal stress design technique with a simplified turbine blade. Structural safety for strength and buckling stability was confirmed by the developed analysis program based on the laminate theory to minimize the design procedure. After modifying the preliminary design result with additional structural components such as skin, foam sandwich and mounting joints, stresses, strains, displacements, natural frequency, buckling load and fatigue life were analyzed by the finite element method. Finally these results were confirmed by comparing with IEC1400-1 specification.

• Geophysics and Geophysical Exploration
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• 제18권4호
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• pp.232-240
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• 2015

Magnetotelluric (MT) survey investigates electrical structure of subsurface by measuring natural electromagnetic fields on the earth surface. For the accurate interpretation of MT data, the precise three-dimensional (3-D) modeling algorithm is prerequisite. Since MT responses are affected by electrical anisotropy of medium, the modeling algorithm has to incorporate the electrical anisotropy especially when analyzing time-lapse MT data sets, for monitoring engineered geothermal system (EGS) reservoir, because changes in different-vintage MT-data sets are small. This study developed a MT modeling algorithm for the simulation MT responses in the presence of electrical anisotropy by improving a pre-existing staggered-grid finite-difference MT modeling algorithm. After verifying the developed algorithm, we analyzed the effect of vertical transversely isotropic (VTI) anisotropy on MT responses. In addition, we are planning to extend the applicability of the developed algorithm which can simulate not only the horizontal transversely isotropic (HTI) anisotropy, but also the tiled transversely isotropic (TTI) anisotropy.

• Proceedings of the Plant Resources Society of Korea Conference
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• 한국자원식물학회 2003년도 춘계 학술발표대회
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• pp.138-139
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• 2003

To investigated the effect of liquid culture conditions and nutrient sources on the formation with bioactive substance of Paeilomyces japonica and Cordyceps militaris cultivated in the country, the result are as follow; The growth temperature of two mycelia is 25$^{\circ}C$ and the proper temperature for cordycepin growth is around 20$^{\circ}C$. The formation amount of bioactive substance by nutrient sources reached its peak with using 2% glucose and 1% galactose in case of carbon sources and 0.4% inorganic compound in case of nitrogen sources. Also, the ratio of C/N was optimal with 3% glucose 1% peptone. For a natural medium, most grains were sufficient but the soybean oil was superb. The formation amount of protein-binding polysaccharide that are used for anticancer substance was in proportion to the growth rate of mycelium, had lots of aeration and showed a trend of increasing when the acidity lower. and the content of structural protein showed a trend of increasing when the acidity lower. However, the content of the structural hexosamin did not get a great the effect of culture conditions and nutrient sources. The constitution of monosaccharide that organizes a protein-binding polysaccharide greatly changed in proportion to carbon sources. When Paecilomyces japonica cultured in a silkworm larvae for 30 days, the content of cordycepin was 204.5 mg/100mL as a dry weight in the fruiting body, 41.8 mg/100mL in mycelium and larva, and the content for each bottle was average 29.5 mg/100mL. In case of Cordyceps militaris for 45days, the fruiting body was 563.5 mg/100mL, the larva and the mycelium was 86.1 mg/100mL, and the content for each bottle was average 65.0 mg/100mL.