• Journal of the Korea Society of Computer and Information
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• v.22 no.2
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• pp.37-44
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• 2017

Wireless sensor networks are composed of many wireless sensor nodes that are sensing the environments. These networks have many constraints that are resource constraints, wireless communication, self-construction, etc. But they have many applications that are monitoring environment, tracking the object, etc. In this paper, a mechanism of finding QoS Satisfied multi-path is proposed in wireless sensor networks. In order to satisfy the QoS requirement, the proposed mechanism extends the AODV protocol to find multiple paths from a source node to a destination node by using the additional AODV message types that are proposed. This mechanism will be used to support many QoS applications such as minimum delay time, the better reliability and the better throughput by using the QoS satisfied multi-path. Overheads of the proposed mechanism are evaluated using simulation, and it is showed that QoS satisfied multiple paths are found with a little more overhead than the AODV mechanism.

• Journal of Korean Library and Information Science Society
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• v.38 no.3
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• pp.5-23
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• 2007

In the knowledge economy era, the library must guide the further distribution and an extension of knowledge and information. It implies the fact that the optimal management of library is important and becomes the precondition. And there is a necessity which tries to observe its vertical and horizontal spectrum. This research analyzed the complexity of library management environments, diversification of management paradigms and techniques and its recently trends based on the theories of new public management and administrative reforms of the advanced nations.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.251-252
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• 2008

Throughput and quality-of-service (QoS) over multi-cell environments are two of the most challenging issues that must be addressed when developing next generation wireless network standards. Currently, multiple-input/multiple-output (MIMO), inter-cell coordination and multi-hop relay technologies are viable options for improving channel capacity or coverage extension. Nevertheless, severe QoS degradation occurs in the outer region of multi-cells due to significant interference from neighboring cells or relay stations, thereby limiting overall performance. Therefore, we propose a scheme which adapted to hybrid relaying.

• ETRI Journal
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• v.28 no.4
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• pp.509-512
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• 2006

In a real environment, sound recordings are commonly distorted by channel and background noise, and the performance of audio identification is mainly degraded by them. Recently, Philips introduced a robust and efficient audio fingerprinting scheme applying a differential (high-pass filtering) to the frequency-time sequence of the perceptual filter-bank energies. In practice, however, the robustness of the audio fingerprinting scheme is still important in a real environment. In this letter, we introduce alternatives to the frequency-temporal filtering combination for an extension method of Philips' audio fingerprinting scheme to achieve robustness to channel and background noise under the conditions of a real situation. Our experimental results show that the proposed filtering combination improves noise robustness in audio identification.

• Transactions of Materials Processing
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• v.16 no.1 s.91
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• pp.31-35
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• 2007

Automotive weather strip should have good weather ability, sealability, durability, etc. to perform its duty as body sealing for vehicles under different harsh environments. Due to its comprehensive properties, thermoplastic vulcanizate(TPV) is widely employed in weather strip as alternative for ethylene propylene diene rubber(EPDM). In this study, the influences of the recycled TPV on the tensile strength and hardness were investigated. As results of the injection molding experiment, the recycled TPV's tensile strength and hardness were higher than the virgin TPV and recycled TPV's extension was improve. The morphology showed that recycled TPV's rubber particles became smaller than virgin TPV's rubber particles.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06a
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• pp.412-414
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• 2006

그리드 네트워크에서 MPI를 사용하여 지리적으로 산재된 컴퓨팅 자원을 활용하고 복잡한 문제를 해결하기 위한 MPICH-G2는 사설 IP 클러스터를 지원하지 못한다는 단점을 가지고 있다. MPICH-G2가 가지는 이러한 문제점을 해결하는 방법으로서 사설 IP 클러스터를 지원하는 MPICH-GP를 NAT와 프락시를 병용하여 설계하고 구현하였다. 사설 IP 클러스터의 프론트 노드에 프락시를 두고, 이를 통해 내부 계산 노드로의 통신 링크를 중계한다. 따라서 사설 IP 클러스터와 공인 IP 클러스터가 혼재된 네트워크에서도 적정한 경로를 설정하고 성공적으로 MPI 작업을 수행할 수 있다. 본 논문에서는 MPICH-GP의 성능을 기존의 MPICH-G2와 비교하였다. 그리드 환경에서 MPICH-GP는 MPICH-G2의 80% 이상의 성능을 보이며 rank 관리기법을 적용한 경우는 95% 이상의 성능을 나타낸다.

• Journal of the Korea Society of Computer and Information
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• v.11 no.3
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• pp.239-248
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• 2006

Current context-aware applications In ubiquitous computing environments make the assumption that the context they are dealing with is correct. However, in reality, both sensed and interpreted context informations are often uncertain or imperfect. In this paper, we propose a probability extension model to ontology-based model for rep resenting uncertain contexts and use Bayesian networks to resolve about uncertainty of context informations. The proposed model can support the development and operation of various context-aware services, which are required in the ubiquitous computing environment.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.04a
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• pp.1065-1067
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• 2012

의사 결정을 위한 추천 시스템에 유용하게 쓰이는 스카이라인 계산은 데이터간의 비교에 상당한 시간이 소요되기 때문에 추천 서비스를 실시간에 하기 위해서는 스카이라인을 사전에 계산해 두는 것이 일반적이다. 그러나 모바일 환경에서는 사용자의 위치에 따라 스카이라인이 변하기 때문에, 사전에 계산해 놓은 스카이라인을 조정하는 다양한 연구가 진행되고 있다. 본 연구에서는 이동하는 사용자에게 품질 높은 데이터를 추천해 주기 위해 스카이라인을 확장하는 기법들을 제안하고 이들을 분석해 보고자 한다.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.2
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• pp.73-79
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• 2020

This study was conducted to develop a technique for the stable production of Italian ryegrass(IRG) seeds in reclamation sites. Harvesting 35 days after heading in Autumn resulted in the highest production, an average of 2,232kg/ha. The production yield decreased due to seed loss as harvesting was delayed to 45 and 55 days post-heading. For the harvested 35 days post-heading, under growing rice sowing resulted in 80% seed yield of after rice sowing's; spring sowing resulted in 40%. After rice sowing using the domestic IRG seeds of 30kg/ha produced the highest seed yield of 2,507kg/ha. The highest straw yield has resulted when using the imported IRG seeds of 20kg/ha for after rice sowing 35 days post-heading fresh weight 36,667kg/ha, dry weight 14,500kg/ha, and TDN weight 7,895kg/ha.

• Biomedical Science Letters
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• v.13 no.3
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• pp.197-206
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• 2007

P2X receptors are membrane-bound ion channels that conduct $Na^+,\;K^+$, and $Ca^{2+}$ in response to ATP and its analogs. There are seven subunits identified so far ($P2X_1-P2X_7$). $P2X_2$ receptors are known to be expressed in a wide range of organs including brains and adrenal grands. PC12 cells are originated from adrenal grand and differentiated by nerve growth factor or pituitary adenylate cyclase activating poly peptide (PACAP). Previous studies indicate that $P2X_2$ receptor activation in PC12 cells couples to $Ca^{2+}-dependent$ release of catecholamine and ATP. It is known that acidic pH potentiates ATP currents at $P2X_2$ receptors. This leads to a hypothesis that $P2X_2$ receptors may play an important role in PC12 cell differentiation, one of the characteristics of which is neurite outgrowth, induced by the hormones under lower pH. In the present study, we isolated several clones which potentiate neurite outgrowth by PACAP in acidic pH (6.8), but not in alkaline pH (7.6). RT-PCR and electrophysiology data indicate that these clones express only functional $P2X_2$ receptors in the absence or presence of PACAP for 3 days. Potentiation of neurite outgrowth resulted from PACAP (100 nM) in acidic pH is inhibited by the two P2X receptor antagonists, suramin and PPADS ($100\;{\mu}M)$ each), and exogenous exprerssion of ATP-binding mutant $P2X_2$ receptor subunit ($P2X_2[K69A]$). However, acid sensing ion channels (ASICs) are not involved in PACAP-induced neurite outgrowth potentiation in lower pH since treatments of an inhibitor of ASICs, amyloride ($10\;{\mu}M$), did not give any effects to neurite extension. The vesicular proton pump ($H^+-ATPase$) inhibitor, bafilomycin (100 nM), reduced neurite extension indicating that ATP release resulted from $P2X_2$ receptor activation in PC12 cells is needed for neurite outgrowth. These were confirmed by activation of mitogen activated protein kinases, such as ERKs and p38. These results suggest roles of ATP and $P2X_2$ receptors in hormone-induced cell differentiation or neuronal synaptogenesis in local acidic environments.