• Journal of the Korea Society of Computer and Information
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• v.10 no.4 s.36
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• pp.93-102
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• 2005

Excessive traffic of P2P applications in the limited communication environment is considered as a network bandwidth problem. Moreover, Though P2P systems search a resource in the phase of search using weakly connected systems(peers' connection to P2P overlay network is very weakly connected), it is not guaranteed to download the very peer's resource in the phase of download. In previous P2P search algorithm (1), we had adopted the heuristic peer selection method based on Random Walks to resolve this problems. In this paper, we suggested an adaptive P2P search algorithm based on the previous algorithm(1) to reform the node distribution rate which is affected in unit peer ability. Also, we have adapted the discriminative replication method based on a query ratio to reduce traffic amount additionally. In the performance estimation result of this suggested system, our system works on a appropriate point of compromise in due consideration of the direction of searching and distribution of traffic occurrence.

• Journal of fish pathology
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• v.35 no.2
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• pp.157-165
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• 2022

Single-cycle viruses generated by reverse genetic technology are replication-incompetent viruses due to the elimination of gene(s) essential for viral replication, which provides a way to overcome the safety problem in attenuated viruses. Infectious hematopoietic necrosis virus (IHNV) is a major pathogen causing severe damage in cultured salmonid species. In the present study, we generated a single-cycle IHNV lacking the transmembrane and cytoplasmic domain in the G gene (rIHNV-GΔTM) and evaluated the prophylactic potential of rIHNV-GΔTM in rainbow trout (Oncorhynchus mykiss). To produce rIHNV-GΔTM, IHNV G protein-expressing Epithelioma papulosum cyprini (EPC) cells were established. However, as the efficiency of rIHNV-GΔTM production in EPC cell clones was not high, fish were immunized with a low-tittered single-cycle virus (1.5 × 10² PFU/fish). Despite the low dose, the single-cycle IHNV induced significant protection in rainbow trout against IHNV infection, suggesting high immunogenicity of rIHNV-GΔTM. No significant difference in serum ELISA titers against IHNV between the rIHNV-GΔTM immunized group and the control group suggests that the immunized dose of rIHNV-GΔTM might be too low to induce significant humoral adaptive immune responses in rainbow trout. The involvement of adaptive cellular immunity or innate immunity in the present significantly higher protection by the immunization with rIHNV-GΔTM should be further investigated to know the protection mechanism.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.5
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• pp.187-195
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• 2008

In MANET, it is important to efficiently manage data objects and traffic to improve network throughput and response time. This paper proposes a connection-degree based data object search and replication scheme in mobile ad-hoc networks. In this method, information about the path data object providers is stored at the cache of a cluster header at which lots of queries arrive, so that, to reduce the load of the cluster header, replicas can be created at its neighboring nodes. The method proposes an algorithm that picks up a cluster header among mobile nodes and makes it possible to search for and utilize adaptive and up-to-date information in MANET. The method is expected to be effective since it enables access to data objects in spite of broken links among mobile nodes with an enhancement in network response time of searching and a decrease in communication costs. The efficiency of this system was verified via simulation.

• The KIPS Transactions:PartC
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• v.9C no.6
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• pp.911-918
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• 2002

An important issue in the design of future Personal Communication Service (PCS) networks is the efficient management of location information. In this paper, we propose an adaptive distributed dynamic location management algorithm that stores the position of the mobile terminal in k of the n location information databases (LIDs). The proposed algorithm chooses adaptively k. replication factor according to both the space locality of LIDs in wireless mobile networks and the location query popularity to local mobile terminal from remote mobile terminals. The performance of proposed algorithm is evaluated by both an analytical model and a simulation. Based on the results of performance evaluation, we know that the performance of the proposed algorithm is better than that of Krishnamurthi's algorithm regardless of call-mobility ratio.

• International Journal of Computer Science & Network Security
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• v.23 no.5
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• pp.7-12
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• 2023

Remote sensor systems are utilized in a few applications, including military, restorative, ecological and family unit. In every one of these applications, vitality use is the deciding component in the execution of wireless sensor systems. Thusly, strategies for information steering and exchanging to the base station are critical in light of the fact that the sensor hubs keep running on battery control and the vitality accessible for sensors is constrained. There are two explanations for the various leveled directing Low Energy Adaptive Clustering Hierarchy convention be in investigated. One, the sensor systems are thick and a considerable measure of excess is engaged with correspondence. Second, with a specific end goal to build the versatility of the sensor arrange remembering the security parts of correspondence. In this exploration paper usage of LEACH steering convention utilizing NS2 test system lastly upgraded vitality productive EE-LEACH directing convention guarantees that the chose cluster heads will be consistently conveyed over the system with a specific end goal to enhance the execution of the LEACH convention. EE-LEACH enhances vitality utilization by around 43%.

• Journal of Electrical Engineering and Technology
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• v.8 no.3
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• pp.649-657
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• 2013

DTN flooding based routing protocol replicate the message copy to increase the delivery like hood that overloads the network resources. The probabilistic routing protocols reduce replication cost by forwarding the message to a node that holds high predictability value to meet its destination. However, the network traffic converges to high probable nodes and produce congestion that triggers the drop of previously stored messages. In this paper, we have proposed a routing protocol called as Connection frequency Buffer Aware Routing Protocol (CFBARP) that uses an adaptive method to maintain the information about the available buffer space at the receiver before message transmission. Furthermore, a frequency based method has been employed to determine the connection recurrence among nodes. The proposed strategy has performed well in terms of reducing message drop, message relay while increases the delivery probability.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04a
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• pp.58-60
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• 2003

인터넷을 구성하고 있는 수많은 종류의 하드웨어와 소프트웨어를 통합하여 효율적인 분산 환경을 구성하고자 많은 연구가 진행되어 왔다. 이에 대한 결실의 중요 핵심부분을 이루는 분산 객체 시스템은 인터넷에 접속한 수많은 이용자에게 분산된 환경의 네트워크 자원들을 자유로이 이용하면서, 그 이용의 불편함이 없도록 상당한 투명성을 부가해주고 있다. 본 논문에서는 기존 분산 객체 시스템에서 제공하는 리플리케이션 관리 시스템 내의 결함 모니터링 스타일에 복잡도를 줄인 푸쉬 모니터링 스타일 기반 절충형 장애 검출 시스템을 제안한다. 본 논문에서 제안한 절충형 장애 검출 시스템의 실험결과 나타난 장애 검출과정에서 기존 방법에 비해 신속성과 정확성 측면에서 향상된 성능을 검증할 수 있었다.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.937-940
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• 2004

프로세서 자원, 데이터 저장장치 자원을 제공하면서 가상기관(Virtual Organization)을 구성하는 각 사이트는 사용할 수 있는 네트윅 자원이 한정된 상황에서 애플리케이션 처리량을 극대화하는 최적화된 데이터그리드 시스템을 기대한다. 본 논문에서는 크기가 제한적이며 지리적으로 분산된 데이터 저장공간에서 적응적 데이터 복제 기법을 제안하고 Replica의 지리적 분배를 위한 평가 모델을 제안한다. 이를 위해 논리 시간 데이터 접근 기록 및 통계를 적용하여 복제할 파일들을 구분 하는 이산적 결정 모델을 제안하고 삭제할 Replica 결정에 논리 시간 접근 기록을 적용한다.

• Journal of Veterinary Clinics
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• v.28 no.1
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• pp.113-121
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• 2011

Foot-and-mouth disease (FMD) is a severe vesicular disease of cloven-hoofed animals including domesticated ruminants and pigs. Acute clinical signs may be mild in sheep and goats but are associated with lameness in pigs and mouth lesions with vesicles in cattle. The required condition for a successful pathogen appears to be the ability to counteract both the host innate and adaptive immune response. FMD virus (FMDV) inhibits the induction of antiviral molecules and interferes with the secretory pathway in the infected cell. The surface expression of Major Histocompatibility Complex (MHC) class I molecules is reduced in infected cells. Thus, the ability of the host to recognize and eliminate virus infected cells is decreased. Furthermore, FMDV infection results in a rapid, but transient lymphopenia, reducing the number of T and B cells, and affecting T cell function. The virus appears to premature apoptosis-mediated cell death because it has a very short replication cycle and is able to rapidly produce large amounts of virus. FMDV engages the host protective response at multiple steps to ensure its effective replication and pathogenesis. This review describes the recent pathological and immunological studies to overcome the powerful abilities of FMDV to counteract defense mechanism of host.

• MALSORI
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• no.57
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• pp.175-189
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• 2006

Because a packet loss brings about degradation of speech quality, VoIP speech coders have PLC (Packet Loss Concealment) mechanism. G.711, which is a mandatory VoIP speech coder, also has the PLC algorithm based on pitch period replication. However, it is not robust to burst losses. Thus, we propose two methods to improve the performance of the original PLC algorithm in G.711. One adaptively utilizes voiced/unvoiced information of adjacent good frames regarding to the current lost frame. The other is based on adaptive gain control according to energy variation across the frames. We evaluate the performance of the proposed PLC algorithm by measuring a PESQ value under different random and burst packet loss simulating conditions. It is shown from the experiments that the performance of the proposed PLC algorithm outperforms that of PLC employed in ITU-T Recommendation G.711.