• Polymer(Korea)
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• v.25 no.6
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• pp.818-825
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• 2001

Polycarbonate(PC)/montmorillonite (MMT) nanocomposites were prepared by solution and melt mixing methods. A d-spacing of the nanocomposites was measured by an X-ray diffractometer. Neat montmorillonite (MMT-Na) and MMTs modified by dodecyl ammonium (MMT-DA) or dimethyl hydrogenated tallow 2-ethylhexyl ammonium (MMT-25A) were used. The d-spacing value of PC/MMT-25A and PC/MMT-DA was higher than that of PC/MMT-Na. The d-spacing increased from around 12 to $37AA$ depending on the mixing method. PC was more readily introduced to the gallery of MMT as the molecular weight of PC reduced and the mixing time increased. PC/MMT-25A showed higher thermal stability by thermogravimetric analysis (TGA) than PC/MMT-DA and PC/MMT-Na.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.5
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• pp.415-425
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• 2000

An open architecture manufacturing strategy intends to integrate manufacturing components on a single platform so that a particular component can be easily added and/or replaced. Therefore, the control scheme based upon the open architecture concept is hardware-independent. In this paper, a modular and object oriented approach for a PC-based open robot control system is investigated. A standard reference model for robot systems, which consists of three modules; hardware module, operating system module, and application software module, is first proposed. Then, a PC-based Open Robot Controller(PC-ORC), which can reconfigure robot control systems in various production environments, is developed. The PC-ORC is built upon the object-oriented method, and allows an easy implementation and modification of various modules. The PC-ORC consists of basic softwares, application objects, and additional hardware device on the PC Platform. The application objects are: sequencer, computation unit, servo control, ancillary equipment, external sensor control, and so on. In order to demonstrate the applicability of the PC-ORC, the proposed PC-ORC configuration is applied to an industrial SCARA robot system.

• Journal of Digital Convergence
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• v.19 no.4
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• pp.259-265
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• 2021

This study is a study on the mobile gamification of PC games through analysis of the differences between PC games and mobile games, their respective advantages, and operation patterns, and attempts to extract important key elements of the mobile game process. The main methods of converting PC games to mobile games were analyzed and presented in four ways: complete transplantation, simplification, specialization and new genreization based on the standard of existing PC games. It is expected that PC games can play a role in providing guidelines for mobile gamification of PC games through the case analysis of existing games that have been converted to mobile games, as well as providing a path for the development and trends of game companies.

• Resources Recycling
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• v.14 no.2
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• pp.33-42
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• 2005

Solvent extraction experiments have been performed to separate Nd and Sm from chloride solution with PC88A. The effect of the saponification of PC88A on the extraction and separation of the two metals were studied. In the experimental ranges conducted in this study, the distribution coefficients of Sm were higher than those of Nd and separation factor between them increased with the equilibrium pH of aqueous solution. Saponification of PC88A enhanced the distribution coefficients of Sm and Nd and the separation factor. A chemical model was developed to predict the distribution coefficients of metals and separation factor from the initial extraction conditions. The measured distribution coefficients of Nd and Sm with PC88A and saponified PC88A agreed well with those calculated in this study.

• Land and Housing Review
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• v.14 no.1
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• pp.115-122
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• 2023

Modular construction is popular as a smart building system because it can shorten the construction period. This study proposed a precast concrete (PC) core system that can further shorten modular construction time. The system was developed and its structural performance was verified through computational analysis. The proposed PC core system is a complete PC construction method using dry bonding. The results of the study indicated that the proposed PC core system has structural stability and performance suitable for modular housing.

• Korean Chemical Engineering Research
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• v.56 no.3
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• pp.343-348
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• 2018

Each of the two polycarbonates (PC) of different molecular weights was blended with acrylonitrile-butadiene-styrene (ABS) under high-shear rate processing to afford PC/ABS. Sizes of ABS dispersed phases and mechanical properties of PC/ABS blends were investigated and high-shear rate processing of PC/ABS was carried out by changing screw speed and processing time. Prepared specimens were examined by scanning electron microscope (SEM) to observe morphology changes. Sizes of ABS dispersed phases in PC/ABS blends were observed to decrease gradually as screw speeds increased. Tensile strengths and elongations of specimens were investigated by universal testing method (UTM) to study the influence of molecular weight of PC exerting on PC/ABS blends. As a result, PC1/ABS blends (PC1: higher molecular weight PC) exhibited more strengthened properties than PC2/ABS (PC2: lower molecular weight PC). The tensile strength of PC1/ABS showed an increasing tendency when the screw speed increased, and the elongation did not show a significant decrease, but increased slightly with increasing shear time at a constant screw speed of 1000 rpm.

• Applied Chemistry for Engineering
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• v.26 no.3
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• pp.336-340
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• 2015

Three different types of polycarbonate (PC)/graphene oxide (GO) composites using diphenyl carbonate as a monomer were fabricated by melt polymerization. Those were the PC/GO composite (PC/GO) using a twin extruder, in-situ PC/GO composite (PC/GO-cat.) using a catalyst, and in-situ PC/GO composite (PC/GO-COCl) using a GO-COCl treated by -COCl, Chemical structures of the composites were confirmed by C-H and C=O stretching peak at $3000cm^{-1}$ and $1750cm^{-1}$, respectively. The slope for the storage (G') versus loss (G") modulus plot decreased with an increase in the heterogeneous property of polymer melts. So we can check the GO dispersion of the PC/GO composites using by the slop for G'-G" plot. According to the G'- G" slopes for three different types of PC/GO composites, GO was well dispersed within PC matrix in case of PC/GO and PC/GO-cat.. It was also confirmed by atomic force microscope (AFM) photos. One of the reasons for the poor GO dispersion of PC/GO-COCl is branching and crosslinking processes occurred during polymerization, which was further confirmed by a plot for the complex modulus versus phase difference.

• The Journal of Information Systems
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• v.21 no.4
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• pp.81-108
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• 2012

Growth in the device field is driven by various emerging devices, tablet PC are among the most recognizable. Tablet PC are mobile computing devices enabled with touch screens or pen inputs and provide the functions of various other devices. Firms are interested in utilization of tablet PC on task. Many of firms is considering accepting of tablet PC and is looking forward to performance of tablet PC. Thus, this study propose to discuss strategies for the usage of tablet PC from organizational needs perspective. The goal of this study is to identify factors influencing use of tablet PC and task performance. The results of this study showed that the proposed factors of organizational needs with a exception of Service Flexibility had a positive impact on perceived usefulness that then positively affected Usage of Tablet PC and Task Performance. In addition, perceived task-technology fit had a positive impact on perceived usefulness and Usage of Tablet PC. Finally, Innovative Culture of Organization as a moderating effect significantly influenced the relationship between perceived usefulness, perceived Task-Technology Fit and Usage of Tablet PC. This study is expected to be a reference for a subsequent study associated with Tablet PC at organizational viewpoints.

• Polymer(Korea)
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• v.25 no.6
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• pp.811-817
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• 2001

Crystallization behaviour of bisphenol A polycarbonate(PC) from amorphous phase was studied by varing solvent/nonsolvent ratios in liquid phase. Chloroform and isopropanol were used as a solvent and a nonsolvent, respectively. Samples were characterized by optical microphotography, scanning electron microscope (SEM), X-ray diffaction (XRD), and differential scanning calorimeter (DSC). DSC and XRD measurement were used to determine the crystallinity of PC. The solubility constant seems to critical to control the PC crystallinity in solvent/nonsolvent mixture. The difference in PC crystallinity is explained by the difference in solubility constant of the mixture depending on the solvent/nonsolvent ratio. PC solution of 75/25 wt% (solvent/nonsolvent) ratio produced PC powder showing maximum crystallinity. At this condition solubility constant (9.85) of the mixed solvent was close to PC (9.9).

• Journal of the Korea Society of Computer and Information
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• v.20 no.12
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• pp.61-66
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• 2015

In this paper, we draw a security assessment by analyzing possible vulnerabilities of the designated PC service which is supposed for strengthening security of current online identification methods that provide various areas such as the online banking and a game and so on. There is a difference between the designated PC service and online identification methods. Online identification methods authenticate an user by the user's private information or the user's knowledge-based information, though the designated PC service authenticates a hardware-based unique information of the user's PC. For this reason, high task significance services employ with online identification methods and the designated PC service for improving security multiply. Nevertheless, the security assessment of the designated PC service has been absent and possible vulnerabilities of the designated PC service are counterfeiter and falsification when the hardware-based unique-information is extracted on the user's PC and sent an authentication server. Therefore, in this paper, we analyze possible vulnerabilities of the designated PC service and draw the security assessment.