• Korean Journal of Materials Research
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• v.8 no.9
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• pp.813-818
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• 1998

Ultrafine powders of $\textrm{In}_{2}\textrm{O}_{3}$-doped $\textrm{SnO}_{2}$ were synthesized by a coprecipitation method and the effects of pH value and the amount of In2Q addition on particle size were investigated. The influence of pH value on particle size could be negligible, whereas the amount of $\textrm{In}_{2}\textrm{O}_{3}$ has influenced on particle size and specific surface area. The gas sensitivity to hydrocarbOn($\textrm{C}_{3}\textrm{H}_{8}$, $\textrm{C}_{4}\textrm{H}_{10}$) increased with $\textrm{In}_{2}\textrm{O}_{3}$ addition and reached a maximum at 3wt.% addition. From the results of impedance analysis and I-V characteristics. it was showed that the agglomeration structure of particles and the boundaries between agglomerates were the important factors to determine the gas sensing mechanism.

• Journal of the Korea Fashion and Costume Design Association
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• v.8 no.1
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• pp.81-96
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• 2006

This study aimed to investigate the sociocultural phenomena which affected to clothing change in 1650-1900 and to examine the features of men's necktie in the western art. For this study, information about historic neckwear is obtained from the visual evidence of painted or engraved portraits, contemporary written sources. The covered area of this study was Europe mainly England and France. For this process, research steps were as follows : 1. Investigating the sociocultural phenomena which affect to clothing change through 1650-1900 and analysis of men's clothing and appearance. 2. Finding the changing characteristics of neckties including it's different types, shapes, knots, colors and materials and analyzing similarities and differences of neckties by the times. 3. Examining necktie as one of important and representative icons of male gender identity. The results of the study was as follows: 1. In 1660-1900, men's fashion was simplified in color and detail due to the influence of practical Puritanism and matured civil culture. And British men's fashion spreaded throughout whole European countries and get popularity. 2. In 1650-1720, there were band, cravat and steinkirk. And expecially cravatier, a expert custodian of cravats, was appeared in that period. In 1720-1800, there were stock, solitaire and cravat. In 1800-1850, neckwear were popularized and got various sizes and types up to shape and size of chemise collars. Black stock, scarf cravat and shawl cravat were popular and terms of 'necktie' were used for an certain neckcloth shape. And abundant literature for necktie were published thanks to the development of printing technology in that period. In 1851-1900, the leady-made neckties were spreaded and there were changes in shape, length, knot of necktie up to V-zone formed with shirt's collars and vest types. Neckwear was gradually evolving through four distinct styles, bow tie, scarf or neckerchief, Ascot and four-in-hand. 3. After the mid-l7th Century, as civil culture matured and splendid and extravagant colorful men's wear disappeared, British men's fashion spreaded throughout whole European countries and got popularity. The necktie become an essential ornamental accessory of men's fashion and one of important and representative icons of male gender identity.

• Journal of Powder Materials
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• v.25 no.2
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• pp.137-143
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• 2018

In this study, two types of SKD61 tool-steel samples are built by a selective laser melting (SLM) process using the different laser scan speeds. The characteristics of two kinds of SKD61 tool-steel powders used in the SLM process are evaluated. Commercial SKD61 tool-steel power has a flowability of 16.68 sec/50 g and its Hausner ratio is calculated to be 1.25 by apparent and tapped density. Also, the fabricated SKD61 tool steel powder fabricated by a gas atomization process has a flowability of 21.3 sec/50 g and its Hausner ratio is calculated to be 1.18. Therefore, we confirmed that the two powders used in this study have excellent flowability. Samples are fabricated to measure mechanical properties. The highest densities of the SKD61 tool-steel samples, fabricated under the same conditions, are $7.734g/cm^3$ (using commercial SKD61 powder) and $7.652g/cm^3$ (using fabricated SKD61 powder), measured with Archimedes method. Hardness is measured by Rockwell hardness testing equipment 5 times and the highest hardnesses of the samples are 54.56 HRC (commercial powder) and 52.62 HRC (fabricated powder). Also, the measured tensile strengths are approximately 1,721 MPa (commercial SKD61 powder) and 1,552 MPa (fabricated SKD61 powder), respectively.

• Journal of the Korean Society for Library and Information Science
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• v.41 no.4
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• pp.331-346
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• 2007

The purpose of this study is to research into the characteristics of the printed hooks of ${\ulcorner}$Ch'un-ch'iu(春秋)${\lrcorner}$ commentary in Chosun dynasty by analyzing the types and forms of the existing printed books through the investigation of the bibliographic records of the books. To achieve this purpose, this study selected some of the 'Chak-pan' catalog(冊板目錄) printed in Chosun dynasty which has relatively clear and accurate history and investigated the block printing's condition of the printed books of ${\ulcorner}$Ch'un-ch'iu(春秋)${\lrcorner}$ commentary. In addition. a comprehensive book catalog of ${\ulcorner}$Ch'un-ch'iu(春秋)${\lrcorner}$ commentary was created by retrieving old book catalog from databases by several authoritative information centers and university libraries. Based on this catalog, this research created a new 'Union Catalog(綜合書目)' which contains bibliographies of the ${\ulcorner}$Ch'un-ch'iu(春秋)${\lrcorner}$ commentary through field investigations by identifying, picture-taking. and copying the real books. The new union catalog functions as the basis of the bibliographic analysis of this research.

• Journal of Sensor Science and Technology
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• v.11 no.2
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• pp.77-83
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• 2002

In order to get low cost and portability, semiconductor gas sensor need to have low operating temperature and high sensitivity. $Fe_2O_3$ based sensors which were doped with metal oxide catalysts($MoO_3$, $V_2O_5$, $TiO_2$, and CdO) were fabricated by screen printing method. To improve electrical stability of sensors, the $Fe_2O_3$ sensors were annealed in $N_2$ at $700^{\circ}C$ for 2 hours. The $V_2O_5$ doped $Fe_2O_3$ sensor showed about $80{\sim}90%$ sensitivity at alcohol 1,000 ppm and have good selectivity to hydrocarbon gas and tobacco odors. The fabricated sensor and PIC-chip were employed for portable alarm system.

• Archives of design research
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• v.11 no.1
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• pp.143-152
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• 1998

Recently, rapidly increa~ing internet Websites are providing us with the new kinds of multimedia infonnations without borders acting as the center for exchanging informations. Such new media infonnations through the internet passes infonnations via light on the monitor and provides the various infonnations, with the differentiation from the traditional printing media, it can be searched with electronic commands in limited space. In the process of adapting the new technologies, new media has successfully responded to the fast change and the development of its needs by experiencing the trials and errors, steadily establishing the stable position with its new infonnation transferring and exchanging methods. The representative hompage of websites of information lransfonnations means the first page containing no lower directories and consist of titles, icons, symbols and addresses and can design them in consideration of graphical process, planning, contents and others. Such hompages are very important since the graphical images shows its visual expressions deciding the total meanings of the hompages. In this research, we have analyzed the relationships between its overall colors and text colors from randomly picked hompages of websites in the internets of various areas. Generally, the homepages are designed with graphical expressions in personal way and the feedbacks and responses of such may differs, but this can be used as reference materials for the analysis of new media in objective way. Also, it can be used as the base informations for arrangement and planning of designs with the characteristics of graphics and Graphical User Intertilces in the backhlfound which are implemented over internet.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.8
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• pp.461-465
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• 2016

n-type silicon shows the better tolerance towards metal impurities with a higher minority carrier lifetime compared to p-type silicon substrate. Due to better lifetime stability as compared to p-type during illumination made the photovoltaic community to switch toward n-type wafers for high efficiency silicon solar cells. We fabricated the front electrode of the n-type solar cell with AgAl paste. The electrodes characteristics of the AgAl paste depend on the contact junction depth that is closely related to the firing temperature. Metal contact depth with p+ emitter, with optimized depth is important as it influence the resistance. In this study, we optimize the firing condition for the effective formation of the metal depth by varying the firing condition. The firing was carried out at temperatures below $670^{\circ}C$ with low contact depth and high contact resistance. It was noted that the contact resistance was reduced with the increase of firing temperature. The contact resistance of $5.99m{\Omega}cm^2$ was shown for the optimum firing temperature of $865^{\circ}C$. Over $900^{\circ}C$, contact junction is bonded to the Si through the emitter, resulting the contact resistance to shunt. we obtained photovoltaic parameter such as fill factor of 76.68%, short-circuit current of $40.2mA/cm^2$, open-circuit voltage of 620 mV and convert efficiency of 19.11%.

• Cartoon and Animation Studies
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• s.46
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• pp.207-231
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• 2017

Printmaking is a field of fine arts and is placed on a vague boundary that is perceived as a commercial product with a popular character due to the speciality of editions. Advances of modern science and technology has developed a new technique of printmaking, and the fusion of printmaking and computer has shown the possibility of reproduction art. Reproduction printmaking has been heavily influenced by photography and extended areas, and the various forms of printing have brought about many changes and attempts by stimulating the possibilities of indirect art at various angles. As the history of printmaking and technology closely relate, the development of computer makes widespread expansion of plural artistry, technological and artistic change. A new conceptual shape can be created on the copied image simply by placing the material of the print on the smoothly flat surface expressed in digital form. The process and the result of such work show the area of unique work which is different from the value of the $\grave{a}$ la carte art or the characteristics of the material given by the print. The deprecated perception of reproducibility evaluated the value of the work in a direct sense of printmaking. It is undeniable that it is devalued by a bundle of works regardless of the value of each edition. However, the physical properties of the prints on the paper are brought up with hand drawings drawn on the canvas by hand. And it becomes an opportunity to show new aspect and change through the process of combining digital print information on paper. The diversity of media is sometimes a controversy of identity between art and technology. In the future, it should be discussed how the limit of the media which can be enjoyed in the field of art can be set as a standard.

• Electrical & Electronic Materials
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• v.10 no.2
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• pp.141-149
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• 1997

L $a_{0.7}$S $r_{0.3}$Mn $O_{3}$ powders were prepared by both GNP(Glycine-Nitrate Process) and solid state reaction method in various of calcination temperature(800-1000.deg. C) and time in air. Also, L $a_{0.7}$S $r_{0.3}$Mn $O_{3}$ cathode contacts on YSZ(Yttria-Stabilized Zirconia) substrate were prepared by screen printing and sintering method as a function of sintering temperature(1100-1450.deg. C) in air. Sintering behaviors have been investigated by SEM(Scanning Electron Microscope) and porosity measurement. Compositional and structural characterization were carried out by X-ray diffractometer and ICP AES(Inductively Coupled Plasma-Atomic Emission Spectrometry) analysis. Electrical characterization was carried out by the electrical conductivity with linear 4 point probe method. As the calcination period increased in solid state reaction method, L $a_{0.7}$S $r_{0.3}$Mn $O_{3}$ phase increased. Although L $a_{0.7}$S $r_{0.3}$Mn $O_{3}$ single phase was obtained only for 48hrs at 1000.deg. C, in GNP method it was easy to get single and ultra-fine L $a_{0.7}$S $r_{0.3}$Mn $O_{3}$ powders with submicron particle size at 650.deg. C for 30min. The particle size and thickness of L $a_{0.7}$S $r_{0.3}$Mn $O_{3}$ cathode contact by solid state reaction method did not change during the heat treatment, while those by GNP method showed good sintering characteristics because initial powder size fabricated from GNP method is smaller than that fabricated from solid state reaction method. Based on enthalpy change from thermodynamic data and ICP-AES analysis, it was suggested to make cathode contact in composition of (L $a_{0.7}$S $r_{0.3}$)$_{0.91}$ Mn $O_{3}$ which have little second phase (L $a_{2}$Z $r_{2}$ $O_{7}$) for high efficient solid oxide fuel cells applications. As (L $a_{0.7}$S $r_{0.3}$)$_{0.91}$Mn $O_{3}$ cathode contact on YSZ substrate was sintering at 1250.deg. C the temperature that liquid phase sintering did not occur. It was possible to obtain proper cathode contacts with electrical conductivity of 150(S/cm) and porosity content of 30-40%.m) and porosity content of 30-40%.

• Journal of the Korean Electrochemical Society
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• v.2 no.4
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• pp.227-231
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• 1999

Disposable, amperometric glucose sensor was constructed using platinised carbon paste electrode. The sensor response was studied by amperometry and cyclic voltammetry applying sample solutions on the strip-type electrode. Platinization of screen-printed carbon paste electrode effectively improved the electrochemical reversibility of a mediator and the analytical characteristics of the sensor. The heterogeneous rate constant for $[Fe(CN)_6]^{4-/3-}$ was $1.45\times10^{-2}cm{\cdot}s^{-1}$. An applied potential of 0.3V vs. Ag/AgCl resulted in the best selectivity for glucose. The apparent Michaelis-Menten constant for glucose on the strip sensor, $K_m^{app}$, was 24.5 mM. To evaluate the analytical performance of the glucose sensor strip, a correlation study was performed with the NOVA S.P, Ultra M analyzer for 30 serum samples containing $80\~297mg/dL$ of glucose: the correlation coefficient value was 0.983. It can be seen that the strip sensor has satisfactory precision and accuracy.