• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.6B
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• pp.1068-1073
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• 1999

On the emergence of ISDN which has been introduced in the year 1980, various services are supported. This paper presents implementation of ISDN user/network protocol analyzer based on PC-extension card. Firmware and software are loaded on the PC-extension card using PC 05. The performance analysis on D-channel signalling on this system is surveyed. The monitoring results satisfiy with ISDN BRI or PRI interfaces.

• Biomolecules & Therapeutics
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• v.18 no.4
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• pp.454-462
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• 2010

The present study investigated the neuroprotective effect of Carpinus tschonoskii MAX and its intracellular protective mechanism on 6-hydroxydopamine (6-OHDA)-induced oxidative damage in PC12 cells. We found that pretreatment of PC12 cells with C. tschonoskii extract significantly inhibited the cell death induced by 6-OHDA in a dose dependent manner. C. tschonoskii extract decreased 6-OHDA-induced apoptotic events such as chromatin condensation, DNA fragmentation, the decrease of Bcl-2/Bax ratio, caspase-3 activation and PARP cleavage. C. tschonoskii extract also reduced generation of 6-OHDA-induced reactive oxygen species and nitric oxide. Furthermore, C. tschonoskii extract up-regulated the myocyte enhancer factor 2 D (MEF2D), a critical transcription factor for neuronal survival, and Akt activity, whereas it inhibited the activity of ERK1/2 and JNK. The results suggest that C. tschonoskii extract decreases 6-OHDA-induced oxidative stress and could prevent PC12 cell apoptosis induced by 6-OHDA via the up-regulation of MEF2D and Akt activity, and thus may have application in developing therapeutic agents for Parkinson's disease.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.6
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• pp.105-112
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• 2019

This study was conducted to examine experimentally the seismic performance of non-ductile reinforced concrete (RC) frames retrofitted with precast(PC) engineered cementitious composite (ECC) wall panels. The seismic performance was investigated through cyclic load tests on RC frame with different aspect ratio (h_w/l_w = 2 and 3) and installation position (center and both side of RC frame) of the PC ECC wall panels. Test results indicated that the seismic strengthening method using PC ECC wall panels is effective to improve significantly the strength, stiffness and energy dissipation capacity of non-ductile RC frame. Based on test results, it can be recommended to install PC ECC wall panel at the center of RC frame for improving the strength and to install slender wall panels at both side of RC frame for increasing ductility.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.6
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• pp.21-30
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• 2002

A preconditioned Navier-Stokes code was parallelized by the domain decomposition technique, and the accuracy of the parallelized code was verified through a comparison with the result of a sequential code and experimental data. Parallel performance of the code was examined on a Myrinet based PC-cluster and a Fast-Ethernet system. Speed-up ratio was examined as a major performance parameter depending on the number of processor and the network communication topology. In this test, Myrinet system shows a superior parallel performance to the Fast-Ethernet system as was expected. A test for the dependency on problem size also shows that network communication speed in a crucial factor for parallel performance, and the Myrinet based PC-cluster is a plausible candidate for high performance parallel computing system.

• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.4 s.23
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• pp.1-6
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• 2006

In terms of the speed-up of the conventional line, the research for a improved turnout was carried out continually around world. A turnout is known that it is the most unstable equipment structurally in the rail system. So, the turnout is needed more stable structure. An accurate assembly of turnout affects traveling qualify of turnout area and running safety. Therefore, a turnout which is pre-assembled at a factory by using the split PC sleeper is transported to construction site recently in advanced countries. In this paper, the performance measurements which estimate the safety of the split PC sleepers which are adopted for the first time to improve performance of turnout are implemented indoors. The split PC sleeper is one of components of the improved turnout. The test is considered of the worst ballast condition under the maintenance work as like STT(Swithc Tie Tamper) or MTT(Multiple Tie Tamper). These experiments results indicate that structural safety for the expansion joint of the split PC sleepers.

• Applied Chemistry for Engineering
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• v.23 no.2
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• pp.138-142
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• 2012

The ${\epsilon}$ type copper phthalocyanine (${\epsilon}$-CuPc), called as a pigment blue 15 : 6, is a significant material to produce a blue pixel in LCD (Liquid Crystal Display) panel. In this study, ${\epsilon}$-CuPc sample was synthesized at various reaction conditions by applying the seed method using ${\epsilon}$-CuPc nanoparticles as a seed. Adequate synthetic conditions of the samples were selected by analyzing and comparing crystalline structure, crystalline purity, microstructure, and synthetic yield of the samples with ${\alpha}$ and ${\beta}$ crystalline CuPc samples. The chemical and crystalline structure of the samples were tested using FT-IR spectrometer and X-ray diffractometry, respectively. The shape of the particle was examined using field emission scanning electiron microscope while the thermal property was tested utilizing thermogravimetric analysis.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.6
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• pp.166-174
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• 2011

The object of this study is to evaluate the structural shear capacity of the PC girder-PC beam joint. The dapped end of PC beam and the ledger of PC girder are usually designed to design load. If the end of PC beam can be designed with continuous end, the dapped end of PC beam and the ledger of PC girder do not need to resist to all loads except dead load and construction load. The experimental program was carried out with 7 specimens containing the variable factors as the anchored method of the hanger bar, design load, be or not exist of ledger bars. As a result, the continuity of the dapped end and the ledger were ensured their safety although the design load was only the dead load and the construction load. The shear critical section was expanded toward the effective depth d, the distance from the supported position of the beam. If the ledger is designed according to PCI Design Handbook, the structural system of the ledger is as to the cantilever slab system. But the ledger of this study is as to the 3 side fixed slab system. Therefore the design of the ledger by PCI Design Handbook will lead to highly conservative results.

• Korean Journal of Construction Engineering and Management
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• v.22 no.6
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• pp.96-106
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• 2021

The PC structure based on the OSC (Off-Site Construction) is mentioned as a representative method of innovation in the construction industry that converts the existing construction environment from site-centered to factory production-transportation-site assembly. However, recent research on PC method has focused on improving the functions of subsidiary materials and improving the production system to increase productivity and institutional / policy R&D that can be universally applied to the life-cycle stage of ordering / design /construction is insufficient. In particular, the absence of standardized cost calculation standards makes it difficult to calculate and verify of objectified appropriate construction cost. So which is an obstacle to the activation of the PC method. In this study, the standards for construction costs of domestic and foreign PC method were surveyed and similar Construction Standard Production Rates were analyzed to confirm the product structure suitable for PC method. Subsequently, the construction procedures and input resources for each PC subsidiary materials were identified through on-site surveys to derive component for subsidiary materials, and the factors of change in the product according to the construction characteristics(height, weight of subsidiary material) were verified. As a result the standard product calculation system suitable for the site installation of the PC method for apartment was presented.

• Journal of Korean Electronics
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• v.26 no.6
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• pp.10-14
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• 2006

유비쿼터스 환경과 맞물려 새로운 성장 동력으로 떠오르고 있는 차세대 PC 분야의 동향과 비전을 점검해본다.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.5
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• pp.211-217
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• 2001

In this paper, we have developed the 6 DOF force display system to be based on the single PC. The system is composed of the force display device, the force reflecting rendering algorithm and the high-speed controller. The previous systems had a problem, that must adopt high performance workstation or 2-PC in order to control the graphics speedily and stably. In this paper, it is possible to improve the problem as to develop its exclusive controller and new rendering algorithm. The proposed new rendering algorithm is based on the Proxy algorithm, which can convert information of the position, the velocity, and the haptic information into the force-data. Especially, as to use the proxy algorithm, we can construct dynamical virtual-environment with the elasticity, the viscosity, the mass, and the friction force. As the result of the experiment, we found that our system has much superior characteristics than some other haptic interfaces, because it can control of 30,000 polygon model constructed virtual object with 1[kHz] haptic interrupt cycle and 20[Hz] graphic interrupt cycle in the single PC based system.