• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2019.08a
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• pp.315-315
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• 2019

• Applied Microscopy
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• v.10 no.1_2
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• pp.1-6
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• 1980

The secretory granul cells in the midgut epithelium of Blattella germanica L. were observed by the electron microscope. These secretory granul cells contain many electron dense granules, and granules are about $200{\AA}$ in diameter respectively. It is easy to distinguish 3 different types of granul cells based on their shapes, location, and staining intensity: 1) The light secretory granul cells and their nucleus are both round form and a number of mitochondria, vacuoles, and other cell organelles appear in the cytoplasm. 2) The other kind of light secretory granul cells are small and oval form but ceil organelles are not well developed in the cytoplasm. This granul cell is surrounded by a few regenerative cells ('nidi'). 3) Dark secretory granul cells are cone shaped, well stained, and endoplasmic reticulum, ribosomes, and a lot of secretory granules are found in the cytoplasm. They are all located in the basal portion of the midgut epithelium.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.6
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• pp.487-492
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• 2010

For developing a two-stroke free-piston hydrogen engine with high efficiency and low emission, determination of the scavenging type is one of the most important factor. In this research, backfire characteristics for loop scavenging were analyzed with the number of piston crevice volume and piston expansion speed. Rapid Compression Expansion Machine, RCEM was used for combustion research of the free piston $H_2$ engine in the experiment. As the results, it was shown that although backfire occurring in a loop scavenging type can be partially controled by a complete exhaust of burned gas, possibility of backfire basically exist due to the structure which piston crevice volumes contact with fresh mixture in a scavenging port. However, a loop scavenging may be considered as combustion chamber of a free piston $H_2$ engine from the point of view that backfire does not occur nearby lean equivalence ratio obtained high thermal efficiency. It was also analyzed that an advances of backfire occurrence timing with increase of the fuel-air equivalence ratio were due to promotion of flame propagation into piston crevice volumes by decrease of the quenching distance.

• Journal of Technology Innovation
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• v.24 no.2
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• pp.143-175
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• 2016

In this study, we have analyzed the impact of firm, innovation and industry characteristics on firm's appropriation strategy focusing of the relative preference of patents and trade secrets by using the Korea Corporate Innovation Survey 2005, 2010 and 2014 data. According to the analysis results, companies with characteristics such as venture, high-technology industry, receipt of public R&D subsidies, performing product innovation, high R&D expenditure, prefer patents to trade secrets relatively. However, firm size and R&D cooperation did not have a statistically significant effect on the relative preference. This shows that policy on appropriation system considering the industry characteristics may be more effective. Companies in the industries with a high market concentration showed that trade secrets are preferred, especially these characteristic was distinctly in small and venture companies. This means that the increase in strategic patent applications of the incumbent firms is able to restrict the patent activities in small and venture companies. Because the excessive increase in strategic patents is likely to constrain the innovation activities of small and venture firms ultimately, policy initiatives to limit the abuse of strategic patent applications is required.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.1
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• pp.31-35
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• 2004

This experiment was performed to observe morphological changes in rice leaf tissue caused by a successive UV-B radiation. Effect of UV-B radiation on the structural alteration of tissue was not visually found, however, Photosynthate containing phosphate was sharply reduced in proportion with an increase of UV-B radiation. Fundamental components of cuticle layer were being degraded after 6 h of UV-B radiation compared to the control. UV-B-induced mesophyll cell appeared altered because of water stress, the shape of chloroplast appeared to be considerably shrunk and chloroplast thylakoid membranes were severely destructed. Primary cell wall of UV-B-stressed tissue was entirely scattered or disappeared, and the secondary cell wall due to lignin synthesis and deposition resulted in being thickened, almost 2-times, compared with the control.

• Journal of Korea Technology Innovation Society
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• v.14 no.4
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• pp.711-735
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• 2011

This study examines whether firms' openness to external knowledge improves their innovative performance and what factors make openness more effective in generating innovation. Using 2008 Korean Innovation Survey in manufacturing sector, this study tests whether openness improves innovative performance and how absorptive capacity, small size and use of appropriation methods to a high degree influence the effect of openness on innovation in Korean manufacturing industries. This study finds the followings: First, the effect of openness varies depending on type of innovation. Openness is more effective for incremental innovation than for radical innovation. Second, there exists complementarity between openness and the R&D intensity when innovation is incremental. When the R&D intensity level is high, the effect of openness on incremental innovation is stronger than on radical innovation. Third, openness is more effective for small firms to perform radical innovation than incremental innovation. Fourth, when a firm uses appropriation methods to a high degree, openness is not effective for incremental innovation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.135-147
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• 2016

Equity-based crowdfunding combines virtual technologies with traditional investing principles. Equity-based crowdfunding is a financing method for startups and small businesses to raise small amounts of capital from a "crowd" of investors. Small businesses can raise capital, advertise product or service, and receive feedback from crowds of investors in exchange for ownership equity in their business. This study examined the operational performance of equity-based crowdfunding in Korea. Data were collected from 125 success and failure equity-based crowdfunding of 75 firms. Results were as follows: First, success firms had a clear vision than failure firms in raising equity-based crowdfunding. Second, success firms had success experiences than failure firms in raising equity-based crowdfunding. Third, success firms had patents to technologies or products that are practical and that customers need. Fourth, success firms had three or more year long-term objectives than failure firms in raising equity-based crowdfunding. Finally, implications of the results were discussed.

• Journal of the Korean Society of Propulsion Engineers
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• v.12 no.2
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• pp.48-56
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• 2008

In the rocket preburner, oxidizer-rich combustion with liquid oxygen and kerosene is very challenging work. The key factor of stable flame is good mixing and that is controlled by the injector performance. We have studied spray characteristics of the oxidizer-rich rocket preburner injector in high pressure environments. The injector is composed of fuel orifices, oxidizer orifices and cooling skirt with liquid oxygen. By using this apparatus, we have taken photographs and measured Sauter mean diameter with changing ambient pressure from 0 to 30 kgf/cm2[g]. Droplet diameter is measured by the image processing technique. From the test results, we could understand spray characteristics of the oxidizer-rich preburner injector and this result could be applied to the development of the oxidizer rich preburner system.

• Journal of the Korean Data and Information Science Society
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• v.22 no.3
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• pp.423-436
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• 2011

Many of the theoretical studies have considered herd behavior as a source of the volatility in financial markets, but there have been few empirical studies on the dynamic herding due to the technical difficulty of detecting herd behavior with time-series data. In this context, this paper proposes a new method for measuring time-varying herd behavior based on QR-GARCH model. Using daily data of KOSPI stocks, this paper provides some empirical evidence for strong and volatile herding among traders of stocks of medium firms, and shows that time-varying herd behavior in traders of some stocks has persistent autocorrelation.

• Korean Journal of Environmental Agriculture
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• v.11 no.3
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• pp.261-268
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• 1992

The membranes of mitochondria and chloroplasts contain a number of pigments that can act as endogenous sensitizers to produce activated oxygen species, most efficiently in blue light, which, in turn, attack functional targets in membranes. Therefore, intense blue light from the sun can exert various adverse effects on the functional and structural integrity of the membranes: one of the biochemical events of these negative effects could be the oxidative degradation of the unsaturated fatty acid constituents of membrane polar lipid. It may be assumed that as a strategy to avoid the light induced fatty acid degradation in membranes plant cells, responding to high intensity blue light, change the fatty acid compositions of membrane lipid in such that more-unsaturated fatty acid constituents are replaced by lessunsaturated fatty acid constituents. The results obtained in the present study, most importantly the measurements of double bond index of membrane polar lipid in concert with other measurements such as light quaility-dependent membrane peroxidation and the activities of membrane-bound proteins, seem to support this assumption.