• Journal of the Korean Geotechnical Society
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• v.27 no.3
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• pp.85-94
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• 2011

Mixtures of sand and rubber particles ($D_{sand}/D_{rubber}=1$) are investigated to explore their characteristics under different stain level. Mixtures are prepared with different volumetric sand fractions ($sf=V_{sand}/V_{total}$). Experimental data are gathered from a resonant column, an instrumented oedometer, and a direct shear tests. Results show that sand and rubber differently control the behavior of the whole mixture with strain level. Non-linear degradation of small strain stiffness is observed for the mixtures with $sf{\geq}0.4$, while the mixtures with low sand fraction ($sf{\leq}0.2$) show significantly high elastic threshold strain. Vertical stress-deformation increases dramatically when the rubber particle works as a member of force chain. The strength of the mixtures increases as the content of rubber particle decreases, and contractive behavior is observed in the mixtures with $sf{\leq}0.8$. Rubber particle plays different roles with strain level in the mixture: it increases a coordination number and controls a plasticity of the mixture in small strain; it prevents a buckling of force chain in intermediate strain; it leads a contractive behavior in large strain.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1213-1219
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• 2010

We evaluated the anti-aging potential and safety of black garlic extract for cosmeceutical ingredient. Black garlic was made by spontaneous fermentation for 40 days at $60{\sim}70^{\circ}C$, 85~95% RH without any additives. The 10% black garlic extract had sweet odor, antioxidant activities and inhibitory activities of skin againg enzymes such as tyrosinase and elastase. The skin safety was performed to evaluate of potential toxicity using the primary irritation test and skin sensitization test. The black garlic extract did not show any adverse reactions such as erythema and edema on intact skin sites at primary irritation test, but on abraded sites, some experimental animals showed very slight erythema. So, the black garlic extract was classified as a practically non-irritating material based on the score 0.23 of primary irritation index. The skin sensitization study was tested by the guinea pig maximization test (GPMT) and Freund's complete adjuvant (FCA) with intradermal injection of 10% black garlic extract. The skin sensitization test showed no skin sensitization. The allergic sensitization depends on tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and interleukin-6 (IL-6). The concentration of IL-6 on challenged tissue of treated with black garlic extract was not significantly different with negative control group (saline treated group). Based on this study, the potential for black garlic as a cosmeceutical ingredient was proven.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37B no.12
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• pp.1091-1101
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• 2012

Device-to-device (D2D) communication is expected to offer local area services with low transmit power and short link distance, even not via any infrastructures. These advantages will lead to the deployment of D2D systems in a massive scale, where the order of magnitude of D2D user density is higher than that of cellular user density. Network-assisted D2D systems, where D2D resources are managed by cellular networks, are unable to support the large number of D2D devices, due to the signaling overhead for control signals. In this case, no coordination can be an answer. This paper considers uncoordinated D2D systems, which is implemented with a number of D2D devices in a large scale. By analyzing the transmission capacity of D2D systems, we found a feasibility condition under which the uncoordinated D2D communications possibly coexist within cellular networks, sharing the uplink spectrum. In addition, we provide guidelines for the operational points of massive D2D communications, giving some knowledge about proper transmit power level and link distance of uncoordinated D2D.

• Journal of Technology Innovation
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• v.26 no.1
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• pp.1-30
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• 2018

This study examines the major changes of research about science and technology administrative system and innovation governance, and suggests future direction through critical review. The subjects of the analysis are papers of such as Korean Public Administration Review, Journal of Technology Innovation and policy reports and government documents published by national research institutes. As a result of the analysis, the research itself has evolved from the part of the government organization to the unique field and main focused historical, normative, comparative analysis and institutional approach. In addition, coordination and integration of science and technology policies have been regarded as important issues in research, and innovation system (NIS) and governance perspectives have begun to be reflected in research. However, it reveals some issues such as small government theory vs big government theory, governance theory vs control tower theory, and shows limitations in problem definition and solution inconsistency, and lack of grand and detailed discourse. Future challenges include the pursuit of evolutionary rationality, the pursuit of diversity in multidimensional research and methods, development of korean policy theory and securing universality.

• Horticultural Science & Technology
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• v.34 no.6
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• pp.924-939
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• 2016

The great economic losses caused by Cucumber mosaic virus (CMV) infection of peppers has led to the development of genetically modified (GM) CMV-resistant peppers. We developed virus-resistant pepper plants using Agrobacterium tumefaciens -mediated transformation. The expressed recombinant protein was purified using nickel-nitrilotriacetic acid resin and immunoaffinity chromatography, and purity was assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Immunoblot analysis revealed the purified CMV coat protein (CMV-CP) had a molecular mass of 25 kDa. After in-gel digestion and desalting, the internal peptide fragments of CMV-CP were sequenced by matrix-assisted laser desorption/ionization-time of flight. Most GM pepper and Escherichia coli BL21 internal peptides had identical peptide sequences and contained 137 of 183 whole peptides in CMV-CP. A quantitative enzyme-linked immunosorbent assay was performed to detect CMV-resistant GM peppers. We also provide basic information about the expressed protein in GM peppers for further safety assessment. The contents of soluble protein and CMV-CP were measured in GM and control peppers cultivated in three different areas of Korea. Statistical significance in terms of cultivation areas, harvest times, generations, and plant tissue origin were determined based on a P value of 0.05. The highest amount of CMV-CP was detected at the seedling stage from plant grown in each region. T3 and T5 showed significantly different levels of CMV-CP from T4 in leaves in the whorl stage. No statistical differences were observed among GM peppers at different stages of maturity in any cultivation area. The results from this study contribute to the safety evaluation of newly designed CMV-resistant GM peppers and provide a standard against which to compare other virus-resistant GM peppers.

• Journal of Home Health Care Nursing
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• v.7 no.1
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• pp.5-14
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• 2000

This study was conducted during the time period of September 1997 to February 1999. in order to provide data concerning important facets of horne care nursing and the degree to which practicing hospital and public health nurses believe themselves to be competent in each area. The study subjects consisted of 610 hospital nurses, 158 public health nurses and 21 other nurses from Seoul and the province of Kyunggi. Korea. Data was collected through self-reporting questionnaires which was used by Kim et al.(1999) to evaluate the status of home health nursing and the varying ideas of self-competence that practicing nurses have. The results of the study were as follows: 1) The mean scores of perceived important components and competencies on home health nursing measured on the Likert 4 point scale were $3.15{\pm}0.36$ for importance. and $2.56{\pm}0.36$ for competency. Of the four categories regarding nursing services, the 'Nursing skill' factor had the highest importance and competency. 2) There were significantly higher scores for hospital nurses' importance components and competencies of home care nursing as compared to those scores for public health nurses. 3) The significant factors of the importance component of home care nursing listed in order of priority were 'general infection control', 'bed sore care skill', 'rehabilitation care', 'keeping maintenance of the client's confidentiality', 'malpractice', 'diabetes patient care', 'ability for problem solving' respectively. In contrast, of low priority in the importance components of home care nursing were 'referring nursing as a job to others'. 'record keeping', 'family dynamics', 'medical equipment', 'economic problems', 'environmental assessment', 'suture removal', 'multidisciplinary coordination' respectively. 4) The high priority of the degree to which practicing nurses believe themselves to be competent in home health nursing were the 'blood sugar test', 'enema skill', 'injection skill', 'skin care', 'bed sore care skill', etc. In contrast, lower competence for home care nursing as perceived by nurses were 'AIDS care', 'family violence care', 'substance abuse care', 'mental health care' respectively.

• Journal of the Korean Geographical Society
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• v.51 no.5
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• pp.667-690
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• 2016

This paper reviews the evolution process of global production network(GPN) discourse, from its origin to the recent theorization, namely GPN 2.0. In so doing, the discursive formation of global production networks is introduced in comparison with a competing discourse global commodity/value chains, with particular attention to conceptual and analytical lacunae in the latter. This article also outlines how the global production network perspective has become a useful discursive and practical tool that allows the examination of the nexus of global economy, transnational corporations, and regional development. Subsequently, a theoretical dearth in the approach is discussed in reference to key critiques, and in this context Yeung and Coe's recent theorization GPN 2.0, which is centered on casual mechanisms and network configurations is reviewed. This paper suggests that the theory adequately addresses the problem of casuality lacking in its precedented conceptual framework, and that it helps exploring the formation and evolution processes of varied production networks(including intrafirm coordination, interfirm control, strategic partnership, and extrafirm bargaining) in connection with competitive dynamics and risky environments. As a result of the theorization, the difference between GPN and the chain approaches has become more apparent, and the idea of extrafirm bargaining is particularly important in the differentiation. Extrafirm bargaining is seen to be a comprehensive networking form inclusive of such GPN 1.0 analytical concepts as value, embeddeness, and power, and research attentive to, and engaging with, the extrafirm networks is expected to help transcending the chain governance approaches' analytical excess of interfirm linkages and industry-centeredness.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.2
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• pp.89-103
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• 2020

As we face an aging society, the demand for personal mobility for disabled and aged people is increasing. In fact, as of 2017, the number of electric wheelchair in the country continues to increase to 90,000. However, people with disabilities and seniors are more likely to have accidents while driving, because their judgment and coordination are inferior to normal people. One of the causes of the accident is the interference of personal vehicle steering control due to unbalanced road surface conditions. In this paper, we introduce a encoder type semantic segmentation algorithm that can recognize road conditions at high speed to prevent such accidents. To this end, more than 1,500 training data and 150 test data including road surface damage were newly secured. With the data, we proposed a deep neural network composed of encoder stages, unlike the Auto-encoding type consisting of encoder and decoder stages. Compared to the conventional method, this deep neural network has a 4.45% increase in mean accuracy, a 59.2% decrease in parameters, and an 11.9% increase in computation speed. It is expected that safe personal transportation will be come soon by utilizing such high speed algorithm.

• Journal of Ecology and Environment
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• v.41 no.10
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• pp.290-301
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• 2017

Background: Forest edges create distinctive ecological space as adjacent constituents, which distinguish between different ecosystems or land use types. These edges are made by anthropogenic or natural disturbance and affects both abiotic and biotic factors gradually. This study was carried out to assess edge effects on disturbed landscape at the pine-dominated clear-cut area in a genetic resources reserve in Uljin-gun, eastern Korea. This study aims to estimate the distance of edge influence by analyzing changes of abiotic and biotic factors along the distance from forest edge. Further, we recommend forest management strategy for sustaining healthy forest landscapes by reducing effects of deforestation. Results: Distance of edge effect based on the abiotic factors varied from 8.2 to 33.0 m. The distances were the longest in $Mg^{2+}$ content and total nitrogen, $K^+$, $Ca^{2+}$ contents, canopy openness, light intensity, air humidity, $Na^+$ content, and soil temperature followed. The result based on biotic factors varied from 6.8 to 29.5 m, coverage of tree species in the herb layer showed the longest distance and coverage of shrub plant in the herb layer, evenness, species diversity, total coverage of herb layer, and species richness followed. As the result of calculation of edge effect by synthesizing 26 factors measured in this study, the effect was shown from 11.0 m of the forest interior to 22.4 m of the open space. In the result of stand ordination, Rhododendron mucronulatum, R. schlippenbachii, and Fraxinus sieboldiana dominated arrangement of forest interior sites and Quercus mongolica, Vitis amurensis, and Rubus crataegifolius dominated spatial distribution of the open area plots. Conclusions: Forest interior habitat lies within the influence of both abiotic and biotic edge effects. Therefore, we need a forest management strategy to sustain the stability of the plant and further animal communities that depend on its stable conditions. For protecting forest interior, we recommend selective logging as a harvesting method for minimizing edge effects by anthropogenic disturbance. In fact, it was known that selective logging contributes to control light availability and wind regime, which are key factors affecting microclimate. In addition, ecological restoration applying protective planting for the remaining forest in the clear-cut area could contribute to prevent continuous disturbance in forest interior.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.14-23
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• 2013

This study evaluated the influence of light quality and intensity during healing and acclimatization on the $CO_2$ exchange rate, growth, and morphogenesis of grafted pepper (Capsicum annuum L.) transplants, using a system for the continuous measurement of the $CO_2$ exchange rate. C. annuum L. 'Nokkwang' and 'Tantan' were used as scions and rootstocks, respectively. Before grafting, the transplants were grown for four weeks in a growth chamber with artificial light, where the temperature was set at $25/18^{\circ}C$ (light/dark period) and the light period was 14 hours $d^{-1}$. The grafted pepper transplants were then healed and acclimatized under different light quality conditions using fluorescent lamps (control) and red, blue, and red + blue light-emitting diodes (LEDs). All the transplants were irradiated for 12 hours per day, for six days, at a photosynthetic photon flux (PPF) of 50, 100, or 180 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. The higher PPF levels increased the $CO_2$ exchange rate during the healing and acclimatization. A smaller increase in the $CO_2$ exchange rates was observed in the transplants under red LEDs. At a PPF of 180 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, the $CO_2$ exchange rate of the transplants irradiated with red LEDs was lowest and it was 37% lower than those irradiated with fluorescent lamps. The $CO_2$ exchange rates of transplants irradiated with blue LEDs was the highest and 20% higher than those irradiated under fluorescent lamps. The graft take was not affected by the light quality. The grafted pepper transplants irradiated with red LEDs had a lower SPAD value, leaf dry weight, and dry matter content. The transplants irradiated with blue LEDs had longer shoot length and heavier stem fresh weight than those irradiated with the other treatments. Leaves irradiated with the red LED had the smallest leaf area and showed leaf epinasty. In addition, the palisade and spongy cells of the pepper leaves were dysplastic and exhibited hyperplasia. Grafted pepper transplants treated with red + blue LEDs showed similar growth and morphology to those transplants irradiated with fluorescent lamps. These results suggest that high-quality grafted pepper transplants can be obtained by healing and acclimatization under a combination of blue and red lights at a high PPF level.