• Journal of the Mineralogical Society of Korea
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• v.12 no.1
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• pp.1-10
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• 1999

Talc (Mg3Si4O10(OH)2), one of the sheet silicate minerals, which is the hydrothermal alteration product of serpentinite at Cheongarm mine was prepared for the high pressure compressibility studies. Energy dispersive X-ray diffraction experiment was carried out using the Synchrotron Radiation with the Mao-Bell type diamond anvil cell at room temperature. Polycrystalline talc was mixed with MgO powder for pressure sensor as well as pressure medium in the sample chamber. High pressure runs were performed at pressures up to 35.2 GPa. Talc shows no phase transition within the present high pressure region. Bulk modulus of this talc was determined by the Birch-Murnaghan equation of state to be 78 GPa assuming its first pressure derivative Ko' of 4.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.950-952
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• 2003

This paper have been studied fabrication and characteristics of disposable pH sensor using MEMS technology. The sensor has two open-well structure, the container for the internal electrolyte and electrode were formed by anisotropically etching a silicon substrate. unlike currently used KCI saturated solution, the structure was introduced hydrogel which take an advantage of miniaturization, bulk product, a low price. PU and CA/TP used to measurement ion detection, one is reference membrane and the other is pH. fabricated sensor is encapsulated entirely with epoxy, finally sensor was estimated various ion sorts and pH ranges.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1168-1170
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• 1993

EHV underground transmission cable characterized by low loss and bulk capacity should have high reliability to be protected fully from external damages, not to speak of its quality. In 345kV underground transmission lines of our country, the usage of frie protection trough is standardized. Fire protection trough consists of combination of trough body, spacer, shutting board, fastener, and etc. and it is required to have a high level of fire-retardant characteristics and mechanical strength. Since 1992, we, GoldStar Cable, with collaboration of Lucky, have participated in the development of fire protect ion trough and completed the type test of manufacturing site and will be supposed to go into mass product within 1993.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.5
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• pp.155-160
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• 2018

The materials used for 3D printing are mainly plastic and metal. These materials are usually used in the powdered form. In order to improve the surface roughness of a manufactured product, these powders should consist of small uniform spherical particles. However, the powdered forms are sold at a considerably higher price than bulk or wired materials. When a wire-type material is used instead of a powder, we can supply a relatively large amount of the material at one time as well as reduce the cost. Moreover, the use of this form of the material will increase the process efficiency. This paper deals with the technology required to feed a wire material in front of the tool movement and discusses the examples used for the verification.

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.365-370
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• 1983

Cellooligosaccharides were prepared from microcrystalline cellulose by acetolysis, deacetylation, and chromatographic fractionation, to determine the optimum time of treatment with acetolysis mixture. The fractionation was accomplished by ethanol-water gradient elution on chromatographic column composed of stearic acid-treated mixture of charcoal and Celite. The amount of initial acetolysis product was increased with the reaction period, however, the acetylated mixture of longer reaction period appeared to contain the greater bulk of methanol-insoluble material. Better yields of most of oligosaccharides were obtained with 3-hr acetolysis. When the reaction time was extended to 4-hr, yields of shorter chain oligosaccharides increased at the expense of the The yields obtained with 3-hr acetclys is from 68.2g of Sigmacell Type 19 were : cellotriose, 1.36g(2.0%) ; -tetraose, 1.64g(2.4%) ; -pentaose, 1.16g(1.7%) ; -hexaose, 0.82g(1.2%) ; and -heptaose, 0.21g(0.3%).

• Journal of Information Display
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• v.12 no.3
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• pp.145-152
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• 2011

Since the discovery of fullerenes as a class of nanostructure compounds, many potential applications have been suggested for their unusual structures and properties. The isolated pentagon rule (IPR) states that all pentagonal carbon rings are isolated in the most stable fullerene. Fullerenes $C_n$ are a class of spherical carbon allotrope group with unique properties. Electron transfer between fullerenes and other molecules is thought to involve the transfer of electrons between the molecules surrounding the fullerene cage. One class of electron transfer molecules is the methanofullerene derivatives ([6,6]-phenyl $C_{61}$-butyric acid methyl ester (PCBM), 4-(2-ethylhexyloxy)-[6,6]-phenyl $C_{61}$-butyric acid methyl ester (p-EHO-PCBM), and 4-(2-ethylhexyloxy)-[6,6]-phenyl $C_{61}$-butyric acid (p-EHO-PCBA), 10-12). It has been determined that $C_{60}$ does not obey IPR. Supramolecular complexes 1-9 and 10-12 are shown to possess a previously unreported host.guest interaction for electron transfer processes. The unsaturated, cis-geometry, thiocrown ethers, (1-9) (described as [X-UT-Y], where X and Y indicate the numbers of carbon and sulfur atoms, respectively), are a group of crown ethers that display interesting physiochemical properties in the light of their conformational restriction compared with a corresponding saturated system, as well as the sizes of their cavities. Topological indices have been successfully used to construct mathematical methods that relate structural data to various chemical and physical properties. To establish a good relationship between the structures of 1-9 with 10-12, a new index is introduced, ${\mu}_{cs}$. This index is the ratio of the sum of the number of carbon atoms ($n_c$) and the number of sulfur atoms ($n_s$) to the product of these two numbers for 1-9. In this study, the relationships between this index and oxidation potential ($^{ox}E_1$) of 1-9, as well as the first to third free energies of electron transfer (${\Delta}G_{et(n)}$, for n = 1-3, which is given by the Rehm-Weller equation) between 1-9 and PCBM, p-EHO-PCBM, and p-EHO-PCBA (10-12) as [X-UT-Y]@R(where R is the adduct PCBM, p-EHO-PCBM, and p-EHO-PCBA group) (13-15) supramolecular complexes are presented and investigated.

• Journal of Intelligence and Information Systems
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• v.24 no.1
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• pp.1-23
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• 2018

From the 21st century, various high-quality services have come up with the growth of the internet or 'Information and Communication Technologies'. Especially, the scale of E-commerce industry in which Amazon and E-bay are standing out is exploding in a large way. As E-commerce grows, Customers could get what they want to buy easily while comparing various products because more products have been registered at online shopping malls. However, a problem has arisen with the growth of E-commerce. As too many products have been registered, it has become difficult for customers to search what they really need in the flood of products. When customers search for desired products with a generalized keyword, too many products have come out as a result. On the contrary, few products have been searched if customers type in details of products because concrete product-attributes have been registered rarely. In this situation, recognizing texts in images automatically with a machine can be a solution. Because bulk of product details are written in catalogs as image format, most of product information are not searched with text inputs in the current text-based searching system. It means if information in images can be converted to text format, customers can search products with product-details, which make them shop more conveniently. There are various existing OCR(Optical Character Recognition) programs which can recognize texts in images. But existing OCR programs are hard to be applied to catalog because they have problems in recognizing texts in certain circumstances, like texts are not big enough or fonts are not consistent. Therefore, this research suggests the way to recognize keywords in catalog with the Deep Learning algorithm which is state of the art in image-recognition area from 2010s. Single Shot Multibox Detector(SSD), which is a credited model for object-detection performance, can be used with structures re-designed to take into account the difference of text from object. But there is an issue that SSD model needs a lot of labeled-train data to be trained, because of the characteristic of deep learning algorithms, that it should be trained by supervised-learning. To collect data, we can try labelling location and classification information to texts in catalog manually. But if data are collected manually, many problems would come up. Some keywords would be missed because human can make mistakes while labelling train data. And it becomes too time-consuming to collect train data considering the scale of data needed or costly if a lot of workers are hired to shorten the time. Furthermore, if some specific keywords are needed to be trained, searching images that have the words would be difficult, as well. To solve the data issue, this research developed a program which create train data automatically. This program can make images which have various keywords and pictures like catalog and save location-information of keywords at the same time. With this program, not only data can be collected efficiently, but also the performance of SSD model becomes better. The SSD model recorded 81.99% of recognition rate with 20,000 data created by the program. Moreover, this research had an efficiency test of SSD model according to data differences to analyze what feature of data exert influence upon the performance of recognizing texts in images. As a result, it is figured out that the number of labeled keywords, the addition of overlapped keyword label, the existence of keywords that is not labeled, the spaces among keywords and the differences of background images are related to the performance of SSD model. This test can lead performance improvement of SSD model or other text-recognizing machine based on deep learning algorithm with high-quality data. SSD model which is re-designed to recognize texts in images and the program developed for creating train data are expected to contribute to improvement of searching system in E-commerce. Suppliers can put less time to register keywords for products and customers can search products with product-details which is written on the catalog.