• Korean Journal of Materials Research
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• v.17 no.9
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• pp.453-457
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• 2007

Interest in use of ink-jet printing for pattern-on-demand fabrication of metal interconnects without complicated and wasteful etching process has been on rapid increase. However, ink-jet printing is a wet process and needs an additional thermal treatment such as an annealing process. Since a metal ink is a suspension containing metal nanoparticles and organic capping molecules to prevent aggregation of them, the microstructure of an ink-jet printed metal interconnect 'as dried' can be characterized as a stack of loosely packed nanoparticles. Therefore, during being treated thermally, an inkjet-printed interconnect is likely to evolve a characteristic microstructure, different from that of the conventionally vacuum-deposited metal films. Microstructure characteristics can significantly affect the corresponding electrical and mechanical properties. The characteristics of change in microstructure and electrical resistivity of inkjet-printed silver (Ag) films when annealed isothermally at a temperature between 170 and $240^{\circ}C$ were analyzed. The change in electrical resistivity was described using the first-order exponential decay kinetics. The corresponding activation energy of 0.44 eV was explained in terms of a thermally-activated mechanism, i.e., migration of point defects such as vacancy-oxygen pairs, rather than microstructure evolution such as grain growth or change in porosity.

• Journal of the Korea Convergence Society
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• v.12 no.9
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• pp.93-98
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• 2021

The change of programming language learning experience on learning motivation was analyzed. Learning a programming language is generally evaluated as a difficult process even for majors. Measuring psychological changes related to programming learning at this point in expanding to non-majors is necessary for learner analysis. The overall learner attitude change was investigated by measuring achievement goals, academic interest, academic self-efficacy, cognitive involvement, and academic self-regulation, which are motivation-related factors. All factors related to learning attitude showed a decrease in the post-test results. This result is interpreted that the difficulty of the learning process decreased the motivation to learn programming. It was found that the greater the difficulty perceived by the learner, the greater the decrease in the motivation to learn. Based on the results of this study, it has implications that a learning environment and learning process that can give feedback and a situation that can reduce the level of learning difficulty felt by learners should be systematically given.

• Journal of Industrial Technology
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• v.28 no.A
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• pp.97-104
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• 2008

Recently, interests on positioning system for location-based services have been significantly increased. Many indoor environment systems using fingerprint scheme have been designed to take more accuracy of positioning, but they are inefficient in adapting to change of environments. In this paper, we focus on a client-based positioning system over WLAN for decreasing installation cost and adapting to change of environments. In the proposed system, APs with stable RSSI are selected as base APs independently for each reference point. Experimental results show that proposed system expands service area approximately 20% much than traditional systems using K-NN algorithm and needs only 20% modification process to fingerprint data compare with traditional systems whenever environment conditions are changed.

• Journal of The Korea Institute of Healthcare Architecture
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• v.20 no.4
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• pp.91-100
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• 2014

Purpose : The purpose of this paper is to analyze the characteristics of hospital architecture constructed in each periods and identify the changing process of hospital architecture in Korea since 1945. Methods : Literature review was conducted while the data of hospitals had been collected and the subject of investigation were selected. The important point of analysis is about design conception, site plan, block plan and hospital form. Results : The characteristics of hospital architecture are identified in each periods. Developed by private sector, hospitals have enlarged their beds and sizes under the competitive environments. In terms of size and external shape, vertical form has become a dominant scene of hospital forms in Korea. Among the dominance of tower-on podium, various block plans have been adopted with hospital streets. Also a few cases of horizontal disintegrated form was introduced. Implications : This paper could be the basic data to organize the history of Korean Hospital Architecture, and insufficient data should be supplemented continuously.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1754-1758
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• 2014

The nucleophilic substitution reactions of bis(Y-aryl) chlorothiophosphates (1) with X-pyridines are investigated kinetically in acetonitrile at $35.0^{\circ}C$. The free energy relationships with both X and Y are biphasic concave upwards with a break point at X = 3-Ph and Y = H, respectively. The sign of cross-interaction constants (CICs; ${\rho}_{XY}$) is positive with all X and Y. Proposed mechanism is a stepwise process with a rate-limiting leaving group departure from the intermediate with all X and Y. The kinetic results of 1 are compared with those of Y-aryl phenyl chlorothiophosphates (2). In the case of Y = electron-withdrawing groups, the cross-interaction between Y and Y, due to additional substituent Y, is significant enough to change the sign of ${\rho}_{XY}$ from negative with 2 to positive with 1, indicative of the change of mechanism from a rate-limiting bond formation to bond breaking.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.4
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• pp.503-508
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• 1997

The change of the structure of homogeneous turbulence subject to irrotational strains has been studied in an anti-Morel type diffuser (center matched cubic contour) using the hot wire anemometry. It was observed that the profiles of mean velocities and turbulence velocities along the center line were stable at the entrance region but rapidly changed near the matching point. The wall induced turbulence at the entrance region grows fast and was diffused toward the center at downstream. It was also observed that the axial turbulence grows faster than the radial one in the middle region of the diffusing flow and that the diffusing process has the vortex compression mechanism due to the conservation of angular momentum. These phenomena are frequently observed at the initial flow region of the free jet.

• Korean Journal of Computational Design and Engineering
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• v.12 no.4
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• pp.245-254
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• 2007

This research proposed feature extraction algorithms as an input of STEP Ap214 data, and feature parameterization process to simplify further design change and maintenance. The procedure starts with suppression of blend faces of an input solid model to generate its simplified model, where both constant and variable-radius blends are considered. Most existing cell decomposition algorithms utilize concave edges, and they usually require complex procedures and computing time in recomposing the cells. The proposed algorithm using reference features, however, was found to be more efficient through testing with a few sample cases. In addition, the algorithm is able to recognize depression features, which is another strong point compared to the existing cell decomposition approaches. The proposed algorithm was implemented on a commercial CAD system and tested with selected industrial product models, along with parameterization of recognized features for further design change.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.5
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• pp.89-96
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• 2018

Ami-dong Crematorium in Busan was established as one of the public facilities in 1929(the period of Japanese Occupation). It is the originator of Busan Yeongnak-Park(永樂公園), the funeral facilities of Busan municipality. The crematorium of Busan region was accepted at an earlier stage inside Japanese Concession in accordance with the opening a port. As Ami-dong Crematorium was constructed as a public facilities, the precedent has been maintained so far, providing a background equipped with the leading public corporation facilities in Busan area. This study was based on the expansion construction document founded by National Archives in Korea. Above all things, this research revealed the establishment and change of Busan Ami-dong Crematorium as the historical point for the formation process of recent public funeral facilities.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.8
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• pp.55-64
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• 1999

In this paper, new gamut-mapping algorithm (GMA) that utilizes variable anchor points (center of gravity on the luminance axis) is proposed. The proposed algorithm increases luminance range, which is reduced from conventional gamut mapping toward an anchor point. In this process, this algorithm utilizes multiple anchor points with constant slopes to both reduce a sudden color change on the gamut boundary of the printer and to maintain a uniform color change during the mapping process. Accordingly, the proposed algorithm can reproduce high quality images with low-cost color devices.

• Journal of the Korean Society for Library and Information Science
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• v.30 no.3
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• pp.85-108
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• 1996

This paper studied the process of changes of the heading which is access point of the catalog in the cataloging Rules. The first described change of the concept of heading, and described change of headings in the Korean Cataloging Rules and Anglo-American Cataloging Rules And then described heading; in the online environment and future of cataloging rules. The concept of the main entry has lost any meaningful purpose in today's online catalog environment despite a multiplicity of definition. To bring cataloging rules up-to-date, Headings of KCR, AhCR2 Chapter 21, the MARC format and KORMARC format need to be revised The revision of this cataloging rules should be based on Hypertext and Hypermedia. A Continued empirical research would be most welcome, and should be incorporated into future cataloging rules.