• 통상정보연구
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• 제5권1호
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• pp.3-20
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• 2003

IT evolution and the e-business has emerged as a new economic activity and beyond the time and space limitations. But the enterprises located in GangWon-Do area have been too inactive in their willingness and readiness to adopt e-business models and processes owing to the lack of the directions of e-business, the insufficient network infrastructures and capitals, etc. In this circumstance, as part of this research, this papers have conducted a survey on the e-business and information conditions and status among the enterprises located in GangWon-Do Chuncheon area. In conclusions, this study on the informatization of the enterprises and e-business enlarge strategies for building competition of local enterprises located in GangWon-Do Chuncheon area.

• 한국주조공학회지
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• 제15권5호
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• pp.514-522
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• 1995

The microstructural evolution with isothermal stirring during semi-solid state processing of hypoeutectic Al-6.2wt%Si alloy was studied. Substructure of the individual primary solid particle in the slurry was investigated through transmission electron microscopy(TEM). Formation of subgrain boundaries on the rheocast Al-6.2wt%Si alloy is observed and the misorientation between the grains is shown typically under 2 degrees by analyzing selected area diffraction (SAD) and convergent beam electron diffraction (CBED) patterns. The existence of high angle grain boundaries are also observed in the alloy. Based upon these observations, mechanisms for the primary particles fragmentation are considered. With isothermal stirring, the dislocation density increases, and the evolution of dislocation cell structure takes place, which is interpreted as a process of achieving uniform deformation by dynamic recovery under applied shear stress.

• 한국지역지리학회지
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• 제20권3호
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• pp.256-258
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• 2014

본 논문의 목적은 미국 노스캐롤라이나 주의 세계적인 첨단산업 클러스터인 리서치트라이앵글파크(RTP)를 대상으로 클러스터의 진화를 추동하는 트리플 힐릭스 주체들의 역할을 밝히는데 있다. 먼저, 노스캐롤라이나 주정부는 RTP 개념의 구상단계에서부터 트리플 힐릭스 거버넌스 체계를 갖추고 촉진자적 지방정부의 역할을 수행함으로써 RTP가 첨단산업 클러스터로 진화를 하는데 매우 중요한 역할을 하였다. 둘째, 지역 대학들은 RTP의 성장 속도에 비해 기업가주의적 모델로의 전환이 다소 지체된 결과, 클러스터의 진화 역동성에 미치는 영향은 다소 제한적 수준에 그치고 있다. 셋째, RTP는 클러스터 형성 초기 단계부터 지금까지 대기업 중심적 지배구조를 취하고 있으나, 과거에 비해 대기업 스핀오프의 증가 및 산-학-연 네트워크의 활성화를 통해 클러스터의 내생적 발전 기반을 갖추어 나가고 있다. 마지막으로, RTP의 지속적 진화에는 외생적 발전 모델에서 트리플 힐릭스 체계의 구축을 통해 내생적 발전 모델로의 전환이 중요한 영향을 미친 것으로 판단된다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2017년도 춘계학술대회
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• pp.641-644
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• 2017

LTE(Long Term Evolution) 기술은 스마트폰 중심의 모바일 인터넷으로 상징되는 상용 통신을 넘어 산업 및 긴급 통신 분야로 사용이 확대되고 있다. 본 논문에서는 다양한 분야로 보급되고 있는 LTE 기술의 전송 성능을 응용 트래픽 수준에서 분석해 본다. 성능 분석은 NS-2를 기반으로 한 컴퓨터 시뮬레이션을 사용하여 수행하며, CBR(Constant Bit rate), VBR(Variable Bit Rate) 등의 트래픽을 분석 대상으로 한다. 본 논문의 결과와 방법은 LTE 기반 네트워크의 연구 및 개발에 활용될 수 있을 것으로 생각된다.

• 한국수소및신에너지학회논문집
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• 제25권4호
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• pp.436-442
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• 2014

$LaCoO_3$ powders synthesized by Pechini process were pulverized by planetary ball-milling to decrease particle size and characterized as a catalyst in alkaline solution for oxygen reduction and evolution reaction (ORR & OER). The changes of physical properties, such as particle size distribution, surface area and electric conductivity, were analyzed as a function of ball-milling time. Also, the variations of the crystal structure and surface morphology of ball-milled powders were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The electrochemically catalytic activities of the intrinsic $LaCoO_3$ powders decreased with increasing ball-milling time, but their electrochemical performance as an electrode improved by the increase of the surface area of the powder.

• ETRI Journal
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• 제37권6호
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• pp.1065-1076
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• 2015

Network densification is regarded as the dominant driver for wireless evolution into the era of 5G. However, in this context, interference-limited dense small cell deployments are facing technical challenges in mobility management. The recently announced results from an LTE field test conducted in a dense urban area show a handover failure (HOF) rate of over 21%. A major cause of HOFs is the transmission failure of handover command (HO CMD) messages. In this paper, we propose two enhancements to HO performance in LTE networks - radio link failure-proactive HO, which helps with the reliable transmission of HO CMD messages while the user equipment is under a poor radio link condition, and Early Handover Preparation with Ping-Pong Avoidance (EHOPPPA) HO, which assures reliable transmission of HO CMD under a good radio link condition. We analyze the HO performance of EHOPPPA HO theoretically, and perform simulations to compare the performance of the proposed schemes with that of standard LTE HO. We show that they can decrease the HOF rate to nearly zero through an analysis, and based on the simulation results, by over 70%, without increasing the ping-pong probability.

• ETRI Journal
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• 제32권4호
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• pp.493-502
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• 2010

The operation time of an encoder is one of the critical implementation issues for satisfying the timing requirements of Long Term Evolution (LTE) systems because the encoder is based on binary operations. In this paper, we propose a design and implementation of a latency efficient encoder for LTE systems. By virtue of 8-bit parallel processing of the cyclic redundancy checking attachment, code block (CB) segmentation, and a parallel processor, we are able to construct engines for turbo codings and rate matchings of each CB in a parallel fashion. Experimental results illustrate that although the total area and clock period of the proposed scheme are 19% and 6% larger than those of a conventional method based on a serial scheme, respectively, our parallel structure decreases the latency by about 32% to 65% compared with a serial structure. In particular, our approach is more latency efficient when the encoder processes a number of CBs. In addition, we apply the proposed scheme to a real system based on LTE, so that the timing requirement for ACK/NACK transmission is met by employing the encoder based on the parallel structure.

• Advances in concrete construction
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• 제3권2호
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• pp.145-159
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• 2015

The evolution of nanotechnology provides materials with advance properties. It's a fast growing area of research to introduce the oxide nanoparticles into the cement pastes to improve their performance. The purpose of this paper is to review the effects of oxide nanoparticles (such as $SiO_2$, $TiO_2$, $Fe_2O_3$, $ZnO_2$, $Cr_2O_3$ and $Al_2O_3$) on both of hardened concrete properties (i.e., compressive strength, split tensile strength and flexural strength, water permeability, Abrasion resistance and pore structure of concrete) and fresh concrete properties (i.e., workability and setting time). Graphical representations of all these parameters were presented to facilitate the comparison of the effect of oxide nanoparticles on concrete processing. The paper also introduces some discussion about future work in this direction by identifying some open research area.

• 통상정보연구
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• 제8권1호
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• pp.51-66
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• 2006

Korea's IT's firms activities have been vigorous more than ever, since the implementation of " Special law on the nurturing IT firms" in 1990. IT evolution and the e-business has emerged as a new economic activity and beyond the time and space limitations. But the Enterprises located in Gangwon-Do Area have been too inactive in their willingness and readiness to adopt IT models and processes owing to the lack of the directions of e-business, the insufficient network infrastructures and capitals, etc., In this circumstance, as part of this research, This Papers have conducted a survey on the e-business and information conditions and status among the Enterprises located Gangwon-Do Area. In Conclusions, this study Study on the Informationalization of the Enterprises and IT firms Enlarge Strategics for building competition of local Enterprises located Gangwon-Do Area.

• Animal Systematics, Evolution and Diversity
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• 제23권1호
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• pp.95-97
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• 2007

This work is a report about the first record of alcid species, Thick-billed Murre (Uria lomvia) in Korea. Four individuals of Thick-billed Murre captured by crab net were obtained in Deajin Port and near the Munam Port. three individuals of Thick-billed Murre searching food were observed at an area two miles away from Munam-Port. We describe characters of Thick-billed Murre with illustrations.