• ETRI Journal
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• v.37 no.4
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• pp.736-742
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• 2015

A serial concatenated decoding algorithm with dynamic threshold is proposed for low-density parity-check codes with short and medium code lengths. The proposed approach uses a dynamic threshold to select a decoding result from belief propagation decoding and order statistic decoding, which improves the performance of the decoder at a negligible cost. Simulation results show that, under a high SNR region, the proposed concatenated decoder performs better than a serial concatenated decoder without threshold with an Eb/N0 gain of above 0.1 dB.

• Proceedings of the Korean Society of Computer Information Conference
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• 2015.07a
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• pp.71-72
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• 2015

WSN의 센서 노드는 제한된 자원으로 인해 보안상의 취약성을 가지며 공격자는 쉽게 임의의 데이터를 삽입하는 허위 데이터 주입 공격을 할 수 있다. WSN에서는 이러한 공격이 치명적이기 때문에 허위 데이터를 가능한 빨리 여과해야 한다. 허위 데이터 주입 공격을 탐지하는 기법으로 동적 여과 기법이 제안되었는데 이 기법은 초기 분배된 비밀키에 대한 재분배가 이루어지지 않아 같은 공격에 계속 노출될 경우 불필요한 에너지 소모가 발생한다. 본 논문에서 제안하는 기법은 효율적인 키 재분배를 통해 허위 데이터를 빨리 감지하고 에너지 효율성을 향상시킨다. 전달 노드에서 허위 데이터가 탐지되면 정의된 알람 메시지를 통해 베이스 스테이션에 보고되고 키 재분배를 수행하여 더 효율적으로 허위 데이터를 감지한다. 그러므로 제안 기법은 기존 기법과 비교하였을 때 허위 데이터를 조기에 감지하고 전체 네트워크의 에너지를 절약한다.

• Journal of Communications and Networks
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• v.15 no.2
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• pp.179-190
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• 2013

Given the bandwidth assignment for dedicated short range communications for use in vehicular ad-hoc network (VANET) and the expected introduction of equipment in the next few years, we elaborate on how VANET can support infotainment services. We define an architectural model for the integration of VANETs and cellular networks, according to a push mode paradigm where VANETs are used primarily to disseminate service announcements and general interest messages. Cooperation with cellular network is addressed by comparing architecture alternatives. A set of information dissemination protocols for VANETs is compared via simulations on a real urban map. Some results from a lab testbed based on IEEE 802.11p boards are presented along with an application developed for Android operating system to demonstrate the concept of the paper.

• Journal of Communications and Networks
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• v.13 no.5
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• pp.511-517
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• 2011

The capacity of wireless ad-hoc networks is analyzed for all kinds of information dissemination based on single and multiple packet reception schemes under the physical model. To represent the general information dissemination scheme, we use (n, m, k)-cast model [1] where n, m, and k (k ${\leq}$ m) are the number of nodes, destinations and closest destinations that actually receive packets from the source in each (n, m, k)-cast group, respectively. We first consider point-to-point communication, which implies single packet reception between transmitter-receiver pairs and compute the (n, m, k)-cast communications. Next, the achievable throughput capacity is computed when receiver nodes are endowed with multipacket reception (MPR) capability. We adopt maximum likelihood decoding (MLD) and successive interference cancellation as optimal and suboptimal decoding schemes for MPR. We also demonstrate that physical and protocol models for MPR render the same capacity when we utilize MLD for decoding.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.353-359
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• 2006

풍력에너지 연구개발은 1970년대 에너지 위기 이후 시작되어 1980년대 초반까지 가격 경쟁력과 기술 부족으로 상용화에 이르지 못하였다. 그러나 1980년대 중반 미국을 시작으로 상업발전에 성공하여 100kW급 풍력발전시스템이 대량 보급되기 시작하였다. 1990대에는 덴마크, 독일, 스페인 등에서 대규모 풍력시장이 형성되었고, 2000년대 들어 대형화에 성공하여 기존 발전에 대한 시장경쟁력을 확보하게 되었다. 본 논문에서는 풍력에너지 보급 확산을 촉진하기 위해 풍력발전 시장의 동향분석과 함께 기술 특성을 분석하였으며 보급 촉진을 도모할 수 있는 확산 전략들을 제시하였다.

• Journal of Korean Neurosurgical Society
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• v.30 no.sup2
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• pp.356-360
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• 2001

Malignant peripheral nerve sheath tumor(MPNST, primary malignant schwannoma) within the spinal canal is very rare. The prognosis of MPNST in the spinal canal is very poor due to the tendency of perineural spread, dissemination throughout subarachnoid space and local recurrance. This report details the authors' experience on the case of primary malignant spinal schwannoma with review of the literatures and other studies.

• Asia Marketing Journal
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• v.22 no.3
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• pp.51-69
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• 2020

This study empirically examines the link between marketing knowledge management and innovation performance focusing on the moderating role of business environmental volatility. We define marketing knowledge management as the integration of knowledge generation, knowledge dissemination and knowledge storage. Using a unique data set that consists of 439 employees at 156 firms in China, we find that knowledge dissemination and knowledge storage have a positive effect on innovation performance. Also found is the negative moderating effect of business environmental volatility on innovation performance. Our findings suggest that firms should strengthen their marketing knowledge management to improve innovation performance and stay flexible to cope with the ever-changing and often volatile market environments.

• Construction Engineering and Management
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• v.11 no.6
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• pp.66-69
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• 2010

• Proceedings of the Korea Technology Innovation Society Conference
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• 2002.11a
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• pp.279-292
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• 2002

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.1329-1330
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• 2005