• 보존과학연구
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• s.32
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• pp.5-24
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• 2011

Neunghwaji(Embossed patterned paper) is a unique paper used for a traditional book cover in Korea. The research was carried out to investigate Neunghwaji's features. Physical property was studied through a test of tensile strength and folding endurance. Also, comparative analysis of virus resistance and waterproof ability was undertaken on Neunghwaji. 1. Folding endurance test showed that strength of non-embossed CB and HB decreased during deteriorating duration. Embossed CN and HN showed the strength increasing at early stage and decreasing from the 27th day of the deteriorating duration. Tensile strength was decreasing in both cases as deterioration progressed. 2. Growth of Arthrinium sp. fungus on embossed paper was 10% less than plain paper while Cladosporium sp. showed 20~30% less growth. Amur cork dyeing(H) showed 10~30% lower fungi growth than Gardenia seed dyeing(C). The result indicated that embossed paper has better virus resistance than Hanji, and Amur cork dyeing has better virus resistance than Gardenia seed dyeing. 3. Average contact angle of CN, CB, HN, and HB was $85{\sim}92^{\circ}$ and NON-N and NON-B was $59{\sim}63^{\circ}$. In detail, CN's contact angle was $1{\sim}7^{\circ}$ higher than CB's; HN was $1{\sim}6^{\circ}$ higher than HB. Therefore, it was found that embossed paper has higher contact angle than Hanji thus the former has better waterproof ability. The research suggested production technique of Neunghwaji and studied its features related to the technique. Neunghwaji was confirmed to have superior quality to Hanji though further study regarding above test result is needed to complement the research.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1514-1516
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• 1999

This paper covers our efforts to improve the low carrier mobility and light instability of hydrogenated amorphous silicon (a-Si:H) films with microcrystalline silicon $({\mu}c-Si)$ films. We successfully prepared ${\mu}c-Si$ films on $CaF_2$/glass substrate by decomposition of $SiH_4$ in RPCVD system. The $CaF_2$ films on glass served as a seed layer for ${\mu}c-Si$ film growth. The XRD analysis on $CaF_2$/glass illustrated a (111) preferred $CaF_2$ grains with the lattice mismatch less than 5 % of Si. We achieved ${\mu}c-Si$ films with a crystalline volume fraction of 61 %, (111) and (220) crystal orientations. grain size of $706\AA$, activation energy of 0.49 eV, and Photo/dark conductivity ratio of 124. By using a $CaF_2$/glass structure. we were able to achieve an improved ${\mu}c-Si$ films at a low substrate temperature of $300^{\circ}C$.

• Korean Journal of Organic Agriculture
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• v.5 no.1
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• pp.45-66
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• 1996

In Korea there is still no basic standard for organic agriculture and organic farmers in Korea do not follow the minimum requirements of IFOAM basic standard Most of them just practice the organic agriculture applying organic fertilizer, commercial seed without legume, rotation and green manure. But they believe this system is a absolutely environmental friendly agricultural system and it produce a safe agricultural product since they are not aware of the basic standard of organic agriculture at all. The overuse of organic fertilizer by some organic farmer have caused some severe problems risk for nitrate and phosphate leaching. In soil profile showed the potential risk for nitrate and phosphate leaching. In the paper, it is discussed on the environmental friendly function and the safe vegetable production by european organic agriculture which keeps the internationally recognized basic standards of organic agriculture. Therefore it is strongly recommended that korean organic farmer have to follow the IFOAM it is strongly in order to practice the environmental agriculture and produce the safe food. And it is also necessary to introduce to Korea the basic standard of organic agriculture which coincides with IFOAM's and Codex of FAO/WHO immediately if they really want to practice an organic agriculture in the country.

• Korean Journal of Environmental Agriculture
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• v.27 no.2
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• pp.205-210
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• 2008

Life cycle assessment(LCA) is acknowledged as a valuable tool to quantify the environment impact of agricultural practice as well as final product(biodiesel) considering whole life cycle of the target product. As a preliminary research of LCA study for rapeseed(Brassica napus L.) biodiesel, the methodological issues which have to be regarded with high priority were dealt with. No life cycle inventory(LCI) based on local data are currently available for LCA of rapeseed cultivation, crushing, and conversion to rapeseed methyl ester(RME) in Korea. In this paper, the life cycle of rapeseed and methodological factors which have to be measured for building LCI of each process are provided and discussed, which are including seed, fertilizer, energy use in rapeseed cultivation environment; and crushing, RME conversion, and transportation in biodiesel production.

• International Journal of CAD/CAM
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• v.5 no.1
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• pp.19-27
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• 2005

As three-dimensional range scanners make large point clouds a more common initial representation of real world objects, a need arises for algorithms that can efficiently process point sets. In this paper, we present a method for extracting smooth surfaces from dense point clouds. Given an unorganized set of points in space as input, our algorithm first uses principal component analysis to estimate the surface variation at each point. After defining conditions for determining the geometric compatibility of a point and a surface, we examine the points in order of increasing surface variation to find points whose neighborhoods can be closely approximated by a single surface. These neighborhoods become seed regions for region growing. The region growing step clusters points that are geometrically compatible with the approximating surface and refines the surface as the region grows to obtain the best approximation of the largest number of points. When no more points can be added to a region, the algorithm stores the extracted surface. Our algorithm works quickly with little user interaction and requires a fraction of the memory needed for a standard mesh data structure. To demonstrate its usefulness, we show results on large point clouds acquired from real-world objects.

• The Journal of Society for e-Business Studies
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• v.20 no.1
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• pp.79-88
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• 2015

Many servers, such as web and database servers, receive a continual stream of requests. The servers should schedule these requests to provide the best services to users. In this paper, a hybrid genetic algorithm is proposed for scheduling divisible requests without interruption in which the objective is to minimize the total stretch. The stretch of a request is the ratio of the amount of time the request spent in the system to its response time. The hybrid genetic algorithm adopts the idea of seed selection and development in order to improve the exploitation and exploration power of genetic algorithms. Extensive computational experiments have been conducted to compare the performance of the hybrid genetic algorithm with that of genetic algorithms.

• CELLMED
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• v.8 no.2
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• pp.6.1-6.7
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• 2018

Myristica fragrans Houtt is commonly known as "nutmeg", it produces two spices: mace and nutmeg. Mace and nutmeg are strongly aromatic in nature and known as jowzabuwa and javetri/bisbasah respectively in the Unani system of medicine. M. fragrans was used as early as 700 BCE by Indian, however, ancient Greeks and Romans were not aware of it. Later Arab traders introduce M. fragrans into Europe followed by Portuguese and Dutch merchants. Mace is very useful medicine in the Unani system of medicine because of its therapeutic uses in salasal al-bawl (urinary incontinence), amrad-i-qalb (cardiac diseases), amrad-i-dimagh (central nervous system), zo'fe bah (sexual debility), amrad al-rahim (uterine diseases), and su-i-hazim (indigestion). The most important constituents of mace essential oil are ${\alpha}-pinene$, sabinene, myrcene, limonene, 1,8-cineole, terpinen-4-ol, myristicin, ${\gamma}-terpinene$, and safrole. The seed and mace extract of nutmeg contain quite high tannins, flavonoids, and terpenoids. Mace has pharmacological functions such as antibacterial and antifungal, anti-inflammatory, analgesic, antidiarrhea, antioxidant, chemoprotective, neuropharmacologic, and antidiabetic properties. To explore the correlation between the traditional uses and the same proven by recent researches, a comprehensive review is highlighted in this paper. Further, pharmacological activities which are not reported in classical texts are also discussed.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.12
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• pp.815-821
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• 2015

Maritime safety has been more critical recently due to the occurrence of shipboard accidents involving prime movers. As such, the propulsion shafting design and construction plays a vital role in the safe operation of the vessel other than focusing on being cost-efficient. Smaller vessels propulsion shafting system normally install high speed four-stroke diesel engine with reduction gear for propulsion efficiency. Due to higher cylinder combustion pressures, flexible couplings are employed to reduce the increased vibratory torque. In this paper, an actual vibration measurement and theoretical analysis was carried out on a propulsion shafting with V18.3L engine installed on small car-ferry and revealed higher torsional vibration. Hence, a rubber-block type flexible coupling was installed to attenuate the transmitted vibratory torque. Considering the flexible coupling application factor, reduction gear stability due to torque variation was analyzed in accordance with IACS(International Association of Classification Societies) M56 and the results are presented herein.

• Plant Biotechnology Reports
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• v.2 no.3
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• pp.179-189
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• 2008

We established an efficient plant regeneration system for Catharanthus roseus L. (G.) Don through somatic embryogenesis. Embryogenic callus was induced from hypocotyl of seed germinated in vitro. Somatic embryogenesis in Catharanthus has been categorized into three distinct stages: (1) initiation and proliferation of embryo; (2) maturation, and; (3) germination or plantlet conversion. Beside plant growth regulators, various stages of embryogenesis were screened for their response to a wide variety of factors (pH, gelrite, light, sugar alcohols, polyethyleneglycol and amino acids), which affect embryogenesis. All of the tested factors had a small to marked influence on embryogeny and eventual conversion to plantlets. The plantlets were acclimatized successfully in a greenhouse. To our knowledge, this is the first report describing a detailed study of various cultural factors which regulate embryogenesis in C. roseus. The results discussed in this paper may be used in mass propagation to produce medicinal raw material, and the embryo precursor cells could be used in genetic modification programmes that aim to improve the alkaloid yield as well.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.3942-3949
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• 2010

Since existing Nate-on Messenger application stores users' personal information in the database of its server, it is extremely venerable to internal threats, not to mention the communication data being transmitted without any safety measures. To solve such problematic areas of the existing application, we have developed a safer messenger application. The messenger application proposed in this paper discloses only the least required personal information of its users and the rest of the personal information is safely encrypted in the database using private passwords. This protective measure prevents the administrator or a third party from misusing the information since he/she will not be able access the information. In addition, users will be able to freely and safely communicate using this new messenger since transmitted data will also be encrypted.