• Korean Journal of Ichthyology
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• v.11 no.2
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• pp.126-133
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• 1999

Ultrastructure of the zona radiata and the micropyle of ripe eggs in the rainbow trout (Oncorhynchus mykiss), catfish (Silurus asotus) and loach (Misgurnus anguillicaudatus) were examined by light, scanning and transmission microscopes. The egg micropyle of rainbow trout and catfish consists of a funnel-shaped vestibule and a tapered canal transversing the zona radiata. The micropyle of rainbow trout and catfish showed the similar structure with flat pit and long canal. The micropylar wall showed the clockwise spiral structure in rainbow trout. The micropyle of the loach showed the type with a hollow pit leading into a short canal and the micropylar wall showed the counterclockwise spiral structure. There are numerous and various size pores at the surface area around the opening in every experimented fish. Interconnecting ridges were observed in the unfertilized eggs of every fish.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.171-174
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• 2004

The stochiometric $AgGaSe_2$ polycrystalline mixture of evaporating materials for the $AgGaSe_2$ single crystal thin film was prepared from horizontal furnace. To obtain the single crystal thin films, $AgGaSe_2$ mixed crystal and semi-insulating GaAs(100) wafer were used as source material and substrate for the Hot Wall Epitaxy (HWE) system, respectively. The source and substrate temperature were fixed at $630^{\circ}C$ and $420^{\circ}C$, respectively. The thickness of grown single crystal thin films is $2.1{\mu}m$. The single crystal thin films were investigated by photoluminescence and double crystal X-ray diffraction(DCXD) measurement. The carrier density and mobility of $AgGaSe_2$ single crystal thin films measured from Hall effect by van der Pauw method are $4.89{\times}10^{17}\;cm^{-3},\;129cm^2/V{\cdot}s$ at 293K, respectively. From the photocurrent spectrum by illumination of perpendicular light on the c - axis of the $AgGaSe_2$ single crystal thin film, we have found that the values of spin orbit splitting ${\Delta}S_o$ and the crystal field splitting ${\Delta}C_r$ were 0.1762 eV and 0.2494 eV at 10 K, respectively. From the photoluminescence measurement of $AgGaSe_2$ single crystal thin film, we observed free excition $(E_X)$ observable only in high quality crystal and neutral bound exciton $(D^o,X)$ having very strong peak intensity And, the full width at half maximum and binding energy of neutral donor bound excition were 8 meV and 14.1 meV, respectively. By Haynes rule, an activation energy of impurity was 141 meV.

• Economic and Environmental Geology
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• v.33 no.5
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• pp.367-377
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• 2000

The purpose of this study is to elucidate the source of U anomaly formed in stream water of the drainage system around the Shinbo talc mine area based on the O, H, S and Sr isotopic characteristics of water masses and wall rocks. The ${\delta}$D and ${\delta}^{18}O$ of surface and ground waters show highly restricted range and plotted on the same meteoric water line, indicating that they are all originated from the meteoric water. The ${\delta}^{34}S$value of the ground water containing high U shows slightly negative (-0.2${\textperthousand}$) and quite distinct from those of the other surface and ground waters that are similar to those of wall rocks (>5.8${\textperthousand}$), indicating that they have a different S isotopic fractionation or less probably, source. The $^{87}Sr/^{86}{Sr}$ratios of water masses around the Shinbo talc mine area show a variable range from 0.724325 to 0.744928, but tend to increase with increasing U concentration of water mass. Although it is not possible to determine precisely the source rock of U anomaly formed in the hydrologic system around the Shinbo talc mine, the evidence obtained from the Sr isotopic compositions strongly suggests that coal schist and/or pegmatite vein could be the most likely candidate for the source rock.

• Design & Manufacturing
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• v.13 no.4
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• pp.23-27
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• 2019

People's interest in the environmental problems of the Earth is growing as they come to the modern world, and research is being actively conducted on how to protect the environment. As a result, the automobile industry, one of the causes of environmental pollution, is also affected. Therefore, research is being conducted to improve the fuel economy and light weight of cars, development of pollution-free cars such as electric cars, and aluminium materials that are lighter than ordinary steel sheets and easier to recycle are gaining attention. In this experiment, the material was formed to form a form of aluminium and the material reduction rate of the side wall of the foam was tested according to the amount of side wall. The material used in the experiment was A3003-O, which is less plastic than normal steel plates, but has excellent corrosion resistance, plasticity and weldability compared to aluminium materials, but has poor tensile strength. For tensile testing, a certain array of Forming Shapes was molded and the height of the Forming was set to 5mm, and the height of the Forming was 4.7mm, indicating that the difference between the first 5mm Forming and the height was not large. In addition, the material reduction rate was tested by giving 15, 0, and -0.15 teas, respectively, and was found to be valuable as a product only for -0.15.

• Archives of Reconstructive Microsurgery
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• v.13 no.2
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• pp.101-106
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• 2004

Purpose : This study evaluated the effect of VEGF in the arterial anastomosis by using light and electron microscopy. Marerials and method : Rats underwent femoral arterial end-to-end anastomosis after transection and topical VEGF treatment. The proximal and distal segments of the femoral arteries was drenched with 1 drop of VEGF $(100ng/100{\mu}l/bottle)$. and when half of the repair was finished, the other 1 drop was drenched and then the repair was continued to complete the anastomosis. Gross and histologic characteristics of arterial wall were assessed after 3 days, 1, 3 and 5 weeks. In the control group, normal saline solution instead of VEGF was dropped with the same method in the anastomosis. Results : The histologic findings of the arterial wall were the vascular remodeling with the infiltration of inflammatory cells at early stages and the tissue fibrosis at lately stages in the anastomotic sites of the control and the VEGF-treated groups. The scanning electron microscopic results were; (1) the anastomotic sites were covered by many irregular cells with long cytoplasmic processes at the early stages. (2) After 1 week, endothelial cells started to cover the anastomotic sites. (3) After 3 weeks, the anastomotic sites were partially covered by endothelial cells in the control group. (4) After 5 weeks, the anastomotic sites were completely covered by endothelial cells in the control and VEGF-treated groups. (5) In the VEGF-treated group, the anastomotic site was completely covered by endothelial cells which directed parallel to longitudinal axis of arteries after 3 weeks. Conclusion : Topical VEGF maintained luminal integrity by decreasing fibrosis and increasing re-endothelialization. These findings suggest that topical VEGF may be a promising new strategy to enhance healing and improve the outcome of vascular anastomosis.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.6_1
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• pp.507-516
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• 2007

Segmentation and organization of the LiDAR (Light Detection and Ranging) data of the Earth's surface are difficult tasks because the captured LiDAR data are composed of irregularly distributed point clouds with lack of semantic information. The reason for this difficulty in processing LiDAR data is that the data provide huge amount of the spatial coordinates without topological and/or relational information among the points. This study introduces LiDAR data segmentation technique by utilizing histograms of the LiDAR height image data and analyzing roof shape for 3D reconstruction and visualization of the buildings. One of the advantages in utilizing LiDAR height image data is no registration required because the LiDAR data are geo-referenced and ortho-projected data. In consequence, measurements on the image provide absolute reference coordinates. The LiDAR image allows measurement of the initial building boundaries to estimate locations of the side walls and to form the planar surfaces which represent approximate building footprints. LiDAR points close to each side wall were grouped together then the least-square planar surface fitting with the segmented point clouds was performed to determine precise location of each wall of an building. Finally, roof shape analysis was performed by accumulated slopes along the profiles of the roof top. However, simulated LiDAR data were used for analyzing roof shape because buildings with various shapes of the roof do not exist in the test area. The proposed approach has been tested on the heavily built-up urban residential area. 3D digital vector map produced by digitizing complied aerial photographs was used to evaluate accuracy of the results. Experimental results show efficiency of the proposed methodology for 3D building reconstruction and large scale digital mapping especially for the urban area.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.5
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• pp.712-718
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• 2006

In order to investigate the analytical uncertainties associated with sampling and analysis of major greenhouse gaseous pollutants(carbon dioxide and methane), we attempted to quantify their adsorptive loss due to the contact with the container wall(such as Tedlar bag and vial). Using the GC/FID method, some basic experimental parameters(such as reproducibility and method detection limit) have been evaluated as part of the essential QA/QC The reproducibilities of carbon dioxide and methane were estimated as 2.02 and 0.2%, respectively. In addition, method detection limits were measured as 0.61 and 0.06 ng, respectively. A test of sample loss rate has also been made for Tedlar bag and vial by assessing the absolute amount of sample loss on the wall. By transferring the samples contained in Tedlar bag to various sizes of Tedlar bags, we measured differences in the absolute loss quantity due to such transfer. In addition, we also examined such loss mechanism as a function of elapsed time and light penetration rate for vial. As results, carbon dioxide and methane have shown about 2% of sample loss due to such contact. It is also noticed that the amount of loss with vial surface is lower than that of Tedlar bag. Therefore, field collection of greenhouse gases using various container types should be made more cautiously to minimize the possibility of sample loss and bias related to such loss.

• Journal of the Optical Society of Korea
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• v.19 no.5
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• pp.508-513
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• 2015

A capacitive-type touch screen panel (TSP) composed of silver nanowire (AgNW) crossing electrodes and transparent bridge structures was fabricated on a polycarbonate film. The transparent bridge structure was formed with a stack of Al-doped ZnO (AZO) electrodes and SU-8 insulator. The stable and robust continuity of the bridge electrode over the bridge insulator was achieved by making the side-wall slope of the bridge insulator low and depositing the conformal AZO film with atomic layer deposition. With an extended exposure time of photolithography, the lower part of the SU-8 layer around the region uncovered by the photomask can be exposed enough to the UV light scattered from the substrate. This leads to the low side-wall slope of the bridge insulator. The fabricated TSP sample showed a large capacitance change of 22.71% between with and without touching. Our work supplies the technological clue for ensuring long-term reliability to the highly flexible and transparent TSP made by using conventional fabrication processes.

• Journal of Plant Biotechnology
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• v.49 no.4
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• pp.271-291
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• 2022

Pectin methylesterase (PME) plays an important role in vegetative and reproductive development and biotic/abiotic stress responses by regulating the degree of methyl-esterification of pectic polysaccharides in the plant cell wall. PMEs are encoded by a large multigene family in higher land plant genomes. In general, the expression of plant PME genes shows tissue- or cell-specific patterns and is induced by endogenous and exogenous stimuli. In this study, we identified PME multigene family members (CsPMEs) from the sweet orange genome and report detailed molecular characterization and expression profiling in different citrus tissues and two fruit developmental stages. We also discussed the possible functional roles of some CsPME genes by comparing them with the known functions of PMEs from other plant species. We identified 48 CsPME genes from the citrus genome. A phylogenetic tree analysis revealed that the identified CsPMEs were divided into two groups/types. Some CsPMEs showed very close phylogenetic relationships with the PMEs whose functions were formerly addressed in Arabidopsis, tomato, and maize. Expression profiling showed that some CsPME genes are highly or specifically expressed in the leaf, root, flower, or fruit. Based on the phylogenetic relationships and gene expression profiling results, we suggest that some CsPMEs could play functional roles in pollen development, pollen tube growth, cross incompatibility, root development, embryo/seed development, stomata movement, and biotic/abiotic stress responses. Our results shed light on the biological roles of individual CsPME isoforms and contribute to the search for genetic variations in citrus genetic resources.

• Restorative Dentistry and Endodontics
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• v.36 no.5
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• pp.385-396
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• 2011

Objectives: This study evaluated the effects of adhesion variables such as the priming concepts of canal wall and the curing modes of adhesives on the sealing ability of a resin-based root canal filling system. Materials and Methods: Apical microleakage of the Resilon-RealSeal systems filled with 3 different combinations of adhesion variables was compared with the conventional gutta-percha filling using a dye penetration method. Experimental groups were SEDC, Resilon (Resilon Research LLC) filling with self-etch RealSeal (SybronEndo) primer and dual-cure RealSeal sealer; NELC, Resilon filling with no etching, Scotchbond Multi-Purpose (3M ESPE) primer application and light-curing adhesive; and TELC, Resilon filling with Scotchbond Multi-Purpose primer and adhesive used under total etch / wet bonding and lightcure protocols. GPCS, gutta-percha filling with conventional AH26 plus sealer, was the control group. Results: The median longitudinal dye penetration length of TELC was significantly shorter than those of GPCS and SEDC (Kruskal-Wallis test, p < 0.05). In the cross-sectional microleakage scores, TELC showed significant differences from other groups at 2 to 5 mm from the apical foramen (Kruskal-Wallis test, p < 0.05). Conclusions: When a resin-based root canal filling material was used, compared to the self-etching primer and the dual-cure sealer, the total etch/wet-bonding with primer and light-curing of adhesive showed improved apical sealing and was highly recommended.