• KSBB Journal
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• v.25 no.2
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• pp.142-154
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• 2010

The protein-bound innerpolysaccharides (IPS) produced by suspended mycelial cultures of Inonotus obliquus have promising potentials as an effective antidiabetic as well as an immunostimulating agents. To enhance IPS production, intensive strain improvement process should be carried out using large amount of UV-mutated protoplasts. During the whole strain-screening process, the stage of solid growth-culture was found to be the most time-requiring step, thus preventing rapid screening of high-yielding producers. In order to reduce the cell growth period in the solid growth-stage, therefore, solid growth-medium was optimized using the statistical methods such as (i) Plackett-Burman and fractional factorial designs (FFD) for selecting positive medium components, and (ii) steepest ascent (SAM) and response surface (RSM) methods for determining optimum concentrations of the selected components. By adopting the medium composition recommended by the SAM experiment, significantly higher growth rate was obtained in the solid growth-cultures, as represented by about 41% larger diameter of the cell growth circle and higher mycelial density. Sequential optimization process performed using the RSM experiments finally recommended the medium composition as follows: glucose 25.61g/L, brown rice 12.53 g/L, soytone peptone 12.53 g/L, $MgSO_4$ 5.53 g/L, and agar 20 g/L. It should be noted that this composition was almost similar to the medium combinations determined by the SAM experiment, demonstrating that the SAM was very helpful in finding out the final optimum concentrations. Through the use of this optimized medium, the period for the solid growth-culture could be successfully reduced to about 8 days from the previous 15~20 days, thus enabling large and mass screening of high producers in a relatively short period.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.107-108
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• 2008

The spectacular development of AMLCDs, been made possible by a-Si:H technology, still faces two major drawbacks due to the intrinsic structure of a-Si:H, namely a low mobility and most important a shift of the transfer characteristics of the TFTs when submitted to bias stress. This has lead to strong research in the crystallization of a-Si:H films by laser and furnace annealing to produce polycrystalline silicon TFTs. While these devices show improved mobility and stability, they suffer from uniformity over large areas and increased cost. In the last decade we have focused on microcrystalline silicon (${\mu}c$-Si:H) for bottom gate TFTs, which can hopefully meet all the requirements for mass production of large area AMOLED displays [1,2]. In this presentation we will focus on the transfer of a deposition process based on the use of $SiF_4$-Ar-$H_2$ mixtures from a small area research laboratory reactor into an industrial gen 1 AKT reactor. We will first discuss on the optimization of the process conditions leading to fully crystallized films without any amorphous incubation layer, suitable for bottom gate TFTS, as well as on the use of plasma diagnostics to increase the deposition rate up to 0.5 nm/s [3]. The use of silicon nanocrystals appears as an elegant way to circumvent the opposite requirements of a high deposition rate and a fully crystallized interface [4]. The optimized process conditions are transferred to large area substrates in an industrial environment, on which some process adjustment was required to reproduce the material properties achieved in the laboratory scale reactor. For optimized process conditions, the homogeneity of the optical and electronic properties of the ${\mu}c$-Si:H films deposited on $300{\times}400\;mm$ substrates was checked by a set of complementary techniques. Spectroscopic ellipsometry, Raman spectroscopy, dark conductivity, time resolved microwave conductivity and hydrogen evolution measurements allowed demonstrating an excellent homogeneity in the structure and transport properties of the films. On the basis of these results, optimized process conditions were applied to TFTs, for which both bottom gate and top gate structures were studied aiming to achieve characteristics suitable for driving AMOLED displays. Results on the homogeneity of the TFT characteristics over the large area substrates and stability will be presented, as well as their application as a backplane for an AMOLED display.

• Journal of Agricultural Extension & Community Development
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• v.21 no.4
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• pp.967-1006
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• 2014

This study attempted to provide policy recommendations in promoting new cooperatives established in agriculture based on the 2012 Cooperative Act. A questionnaire survey was conducted with 195 newly established cooperatives as the policy target of this study. The new cooperatives were classified as three kinds namely as 'Business' Cooperatives', 'Consumers' Cooperatives', 'Social Cooperatives' based on their member attributes and objectives. Interesting to note that, all of these new cooperatives born by the new Act has taken the marketing business as their main stream business. Among the three types, 'Business Cooperatives' are ranked the highest amount of capital shares per person in average, having about 30 members in size. In categorization, 'Business Cooperatives' include farmer cooperatives as majority and employee cooperatives. They are usually involved in both production and marketing and even in processing activities, and have tried to secure their business performance by e-commerce and stable business contracts. Their diverse activities are highly associated with their local community. Consumers' Cooperatives include consumer cooperatives and stakeholder cooperatives in achieving welfare of members. This type has lower share in capital but has over 30 members in a cooperative, taking marketing (distribution) business as main and often take advantage of their social network and physical store. Regional relationships are less than producer cooperatives. 'Social Cooperatives' are established by public interest and have around 10 members and lowest per capital. their business and community activity is similar to the consumer cooperatives. This study recommends the needs of designing suitable business models by these three types of cooperatives in the future, while appropriating their membership size for their tangible business operations. The government policy direction should aim to develop their new business opportunities and its management stabilization, especially in conjunction with the existing agricultural cooperatives (Nonghyup). It must be rather than to provide simply policy supports for establishment. An in-depth study is recommended in this regard.

• KDI Journal of Economic Policy
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• v.13 no.2
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• pp.69-96
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• 1991

Economic circumstances of enterprise began to change after a series of democratization measures in 1987. Accompanied with it, competitive advantage of enterprise began to change as well. By that time Korean enterprises had a competitive advantage based on low wages of labor. Abrupt and steady upsurge in wage, however, weakened competitive advantage based on low wages, upward revaluation of won currency caused by surplus in BOP strengthened upward trend in price increase of export products. An urgent problem in Korea economy is, therefore, to find 'new' competitive advantage. For the time being preserving competitiveness based on cost advantage must inevitably remain our basic strategy in industrial policy. While cost advantage in the past referred to low wage level, this cost advantage must have foundation on the improvment in producing technology, which will increase labor productivity and decrease unit cost of products. Besides, other measure to improve competitiveness can be considered such as increasing the extent of production automation, self-development of new products, and spread and strengthening subcontracting system among various enterprises. In this paper we tried to perceive how subcontracting system as a form of intercompany division of labor operates and to which direction this system proceeds responding to the recent changes in economic circumstances. Speaking more concretly, we tried to perceive how large the gap of bargaining power between mother-company and subcontracting company is and how effectively subcontracting company's technical power contributes to mother-company. Facing up to weakeening of competitiveness, how stably is the partnership between mother-company and subcontracting company established and what measures are being prepared to retore the weakened competitiveness. In conclusion the result of investigation through the questionaire on subcontracting system is positive, from which we can infer the optimistic view of restoring Korean economy's competitiveness.

• Journal of Bio-Environment Control
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• v.17 no.2
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• pp.116-123
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• 2008

This study was carried out to investigate into the effect of light-emitting diode (LED) for the light quality as a light source on the broccoli seed germination and the physiological activity of vegetable sprouts. We have also germinated seeds of the broccoli and applied LED as a light quality such as blue, green, red, white, yellow and red + blue color lights to their sprouts for 14 hours and kept dark for 10 hours at the temperature of $25^{\circ}C$ (day)/$18^{\circ}C$ (night). Broccoli sprouts were extracted by methanol and their physiological activities were examined. All broccoli seeds were germinated at 3 days after seeding regardless of the light color. Total sprout fresh weight were mostly became highest by 0.389g (10 plants) at 8 days after seeding when their sprouts were grown under blue color light. Total phenol compound contents in broccoli sprouts were extremely increased by $83.0\;mg{\cdot}L^{-1}$ under the white light, and total flavonoid contents were most much more by $72.6\;mg{\cdot}L^{-1}$ under the blue light. DPPH radical scavenging activity at $2,000\;mg{\cdot}L^{-1}$ were most highest by 93.5% in broccoli sprouts grown under the white light. Nitrite radical scavenging activity at the concentration of $500\;mg{\cdot}L^{-1}$ in sprout extracts were the most increased by 66.9% under the yellow light, and tyrosinase inhibition activity at $2,000\;mg{\cdot}L^{-1}$ in sprout extracts were by 14.5% under red light.

• Journal of the Korean Society of Radiology
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• v.7 no.6
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• pp.403-408
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• 2013

This study made a tentative estimation of the shielding rate of barium compound by thickness through monte carlo simulation to apply medical radiation shielding products that can replace existing lead. Barium sulfate($BaSO_4$) was used for the shielding material, and thickness of the shielding material specimen was simulated from 0.1 mm to 5 mm by applying $15{\times}15cm^2$ of specimen area, $4.5g/cm^3$ of density of barium sulfate, and $11.34g/cm^3$ density of lead. Entered source was simulated with 10kVp Step in consecutive X-ray energy spectrum(40 kVp ~ 120 kVp). Absorption probability in 40 kVp ~ 60 kVp showed same shielding rate with lead in 3 mm ~ 5 mm of thickness, but it was identified that under 2 mm, the shielding rate was a bit lower than the existing lead shielding material. Also, the shielding rate in 70 kVp ~ 120 kVp energy band showed similar performance as the existing lead shielding material, but it was tentatively estimated as fairly low shielding rate below 0.5 mm. This study estimated the shielding rate of barium compound as the thickness function of x-ray energy band for medical radiation through monte carlo simulation, and made comparative analysis with existing lead. Also, this study intended to verify application validity of the x-ray shielding material for medical radiation of pure barium sulfate. As a result, it was estimated that the shielding effect was 95% higher than the existing lead 1.5 mm in at least 2 mm thickness of barium compound in medical radiation energy band 70 kVp ~ 120 kVp, and this result is considered valid to be provided as a base data in weight lightening production of radiation shielding product for medical radiation.

• Journal of Life Science
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• v.30 no.5
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• pp.428-433
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• 2020

In this study, we created pupal stage extracts of Apis mellifera L. drones for use in cosmetic materials. The effect of the drone pupae extract (DPE) on HDF cells was assessed for analysis of anti-wrinkle activity by collagen or collagenase gene expression, and the skin-lightening effect was studied by in vitro tyrosinase inhibition and B16F10 melanoma assay; the two cells were found to be non-cellular when the concentration of DPE was 100 ㎍/ml. Albutin concentration (positive control) in the whitening test was set at a capacity of 100 ug/ml and m-melanocyte stimulating hormone (α-MSH). A melanin-producing induction material was set at a concentration of 100 nM, and the expression of collagen type I and MMP1 collagenase was measured using HDF cells. MMP1 expression was seen to reduce in a concentration-dependent manner in treatment with DPE. Inhibiting melanin generation with B16F12 cells indicated a tendency to decrease in the DPE treatment group. Both L-Tyrosine and L-DOPA as DPE were used in an in vitro tyrosinase induction test to demonstrate the effects of tyrosinase suppression on concentrations. The higher the concentration of DPE, the greater the wrinkle reduction and whitening effect. In conclusion, it was found that DPE is an effective smoothing and whitening material by increasing collagen generation and inhibiting collagenase expression and reducing melanin production.

• Journal of Animal Environmental Science
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• v.8 no.3
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• pp.135-144
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• 2002

A computer simulation was carried out to investigate the optimum capacity of liquid manure tank spreader which is used as a tractor attachment. Soil physical properties, such as soil moisture content, bulk density, soil hardness and soil types were measured in the 10 major rice production area for computer simulation. Mathematical model which include soil physical properties and vehicle factor was used for computer simulation. Most of the soil type of the investigated area was sandy clay loam. Soil moisture content ranged between 30 and 40% mostly. Soil bulk density was in the range of 1,500 to 1,700 kg/$m^3$. Soil hardness ranged between 1 to 18 $cm^2$. Soil hardness incorporate the effects of many soil physical properties such as soil moisture content, soil type and soil bulk density, and so the range of soil hardness is greater than any other physical properties. The capacity of liquid manure tank spreader was above 3,000 kg$_{f}$ for the most of the investigated areas, and mostly in the range of 4,000 to 6,000 $kg_f$ depending upon the slip. But for the soft soil area such as Andong and Asan, the tractor itself has mobility problem and shows no pulling force for some places. For this area, the capacity of liquid manure tank spreader ranged between 1,000 and 2,000 $kg_f$ mostly, so the capacity of liquid manure tank spreader should be designed as a small capacity trailer compared to the other area.mpared to the other area.

• Journal of Animal Environmental Science
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• v.9 no.2
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• pp.123-130
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• 2003

In this study, current status of domestic deer farms and its feeding were surveyed. The information of supply and demand of feed f3r deers including its industry were also examined and then analyzed to make fundamental data for deer farms and government policy. The results are as follows. 1. Over 40 years old farmers were about 63％ of total deer farms while 20­30 years olds were less than 1％ indicating that young people still evade agriculture. Moreover, considering education, over 52％ of the farmers have bachelor degree showing much higher rates compared to the other agricultural fields. The reason can be assumed that the labor burden is not serious in deer farming while it is not dirty job compared to the other livestock management. Those high­educated people can be easily trained as experts of deer farming to improve its international competition. 2. Most of investigated farms raise Korean spotted deers and Elk showing that the percentage of Elk has greatly increased(However, many farmers have complained about purchasing methods and they insisted that the sales organization should be controlled by government). 3. 57％ of total cost of production is for feed while most of feeds are imported from abroad. It indicated that it is urgent to make counterplan for saving feed cost. 4. It is necessary to develop feeds for deers in the near future while most of the examined farmers currently use normal assorted feed. Typical roughage sources feeds are rice straw, alfalfa hay, browses feed, and so on. Most of them are currently imported except the rice straw indicating urgently needed to develop domestic bulky feed. 5. The present questions are development of processed goods of velvet antler, establishment of reasonable management system, difficulty of velvet antler selling, feed supply, and so on. It is necessary for government and academic world to develop reasonable policy and scientific research program.

• Journal of the Speleological Society of Korea
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• no.63
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• pp.1-8
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• 2004

The non-magnetic materials with non-conductive showing high structure dispersity were developed on the base of natural quartz and lava-scoria which was collected from Je-ju island in Korea, and treated by methane-chemical technology those were obtained novel properties of magnetization through the analyzing. Depending on the processing conditions and subsequent applications the materials produced by strong methane-chemical reaction (MCR) in alcohol solution showed concurrently magnetic, dielectric and electrical properties. The obtained magnetic-electrical powders classified by aggregate complex of their features as segnetomagnetics, containing a dielectric material as a carrying nucleus, particularly the quartz on that surface one or more layers of different compounds were synthesized having thickness up to 10～50 nm and showing magnetic, electrical and other properties. It was confirmed in magnetizing process that powders of quartz and lava-scoria produced by MCR were better oil adsorbent as of oleophilic and floating matter on water surface although their specific gravities are comparably more than 1 in quartz or less than unity, as that of water, in lava-scoira. Therefore, it will be Possible and very useful to remove low density and light gravity oil spillage in difficult recovery from sea and inland water contamination spread on water surface, by marine accident and ship sinking accident occurring frequently in recent years, by way of magnetic adsorbent conveyer system in continuous, if it could be built up the mass Production system of water-floating magnetizable oleophilic adsorbent materials with use of iow cost and good Qualify lava-scoria spread on volcano district in Je-ju island. And, there will also be urgent advent of necessity with strong possibility to develop useful applications of various magnetic functional materials include oleophilic adsorbent for removal of sea oil-contaminants and maritime pollutants, and other kinds of various utilities in industrial applications and practical uses of novel functional materials in the fields of environments and health care applications with in deep expectation.