• Annual Conference of KIPS
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• 2014.11a
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• pp.196-198
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• 2014

Wireless Sensor Networks(WSN) 기반의 Border Surveillance Networks(BSN)는 다양한 제한조건을 동반하며 침입 혹은 환경 등을 감시함을 목적으로 하고 있기 때문에 이벤트 발생시 신뢰적인 데이터 전송은 매우 중요한 부분을 차치하게 된다. 본 논문에서 적용한 대표적인 요구기반 라우팅 방법인 Ad hoc On-demand Distance Vector Routing(AODV)는 BSN 에 적용하였을 경우 홉 수(Hop Count)를 메트릭으로 최적의 경로를 계산하고 선택하여 Uni-Path 로 데이터를 전송하게 된다. 이때 AODV 는 Uni-path 로 데이터 전송을 진행하게 되며 링크의 단절이 빈번히 발생하는 BSN 의 환경적 요인으로 데이터 전송의 신뢰성이 감소하게 될 것이며 이는 비효과적인 데이터 전송을 야기하게 된다. 따라서 본 논문에서는 Multi-path 개념을 도입하여 데이터 전송 시 링크단절에 의해 발생하는 시간의 지연을 줄이고 더욱 신뢰성 있게 데이터를 전송할 수 있는 방법을 제안한다. 제안하는 방법은 송, 수신하는 두 노드의 전송범위에 공통으로 속한 노드들이 전송되는 데이터를 중복 전송하게 된다. 그리하여 링크의 단절이 일어날 경우 발생하는 경로 재 탐색 및 경로복구의 발생 빈도를 줄이고 동시에 데이터 전송률을 증가시켜 신뢰적인 데이터 전송을 하게 된다.

• The Transactions of the Korea Information Processing Society
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• v.7 no.11S
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• pp.3675-3683
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• 2000

The Handoff is the core technical factor that is required when mobile host moves from one area to another, while transmitting and receiving data. The existing works try to minimize the loss of pockets by forwarding packets to the Cell which a mobile host will move to. However, though the loss quantity is little, the accumulated loss can del(rade the performance of the TCP, and can be a serious problem if data is sensitive to the loss of packets. In this paper, we can reduce a memory requesting in FA by restricting the mobile host to move within at most 2 movable cells and design the improved handoff protocol for Mil to receive packets seamlessly in spite of handoff. We can evaluate that the suggested method is superior to the previous method, as a result of comparing with it.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.1
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• pp.141-156
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• 2011

In this paper we develop a link cost function for data delivery in sensor network. Usually most conventional methods determine the optimal coefficients in the cost function without considering the surrounding environment of the node such as the wireless propagation environment or the topological environment. Due to this reason, there are limitations to improve the quality of data delivery such as data delivery ratio and delay of data delivery. To solve this problem, we derive a new cost function using the concept of Partially Connected Neural Network (PCNN) which is modeled according to the input types whether inputs are correlated or uncorrelated. The correlated inputs are connected to the hidden layer of the PCNN in a coupled fashion but the uncoupled inputs are in an uncoupled fashion. We also propose the training technique for finding an optimal weight vector in the link cost function. The link cost function is trained to the direction that the packet transmission success ratio of each node maximizes. In the experimental section, we show that our method outperforms other conventional methods in terms of the quality of data delivery and the energy efficiency.

• Journal of Fashion Business
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• v.12 no.1
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• pp.1-15
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• 2008

This study aims to consolidate the qualitative growth of knit design thru the creation of high value-added brand and design, in the state of active trend for competitive promotion of professional knit brand, by collapsing the border line between the knitwear market and the woven one. In accordance with the market situation of increasing a demand of knitwear products, I wish to awaken the importance of knit design thru this study, to survey domestic knit brand products and their planning directions and to plan for the high value-added knitwear products, thru presenting the problems of knit industry and developing knitwear design. This study is focused on showing process of planning and items developed personally by me in charge of developing products practically at the job site of knit industry. From the stage of planning for goods, I suggested the 2007 s/s goods of M company as a strategy of distinctiveness caused by the problems with rival companies, and also proposed a method conducted by the actual business. Setting up M company's s/s concept of the year 2007, I suggested a plan of quantity, time of forwarding, color, fabrics, etc. as well as the process and schedule thru order, and based on the above result, I made a planning for 2007 s/s knitwear for middle-aged women.

• Annual Conference of KIPS
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• 2000.04a
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• pp.686-691
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• 2000

최근 들어 인터넷의 사용이 급격히 증가함에 따라 인터넷의 백본망에는 패킷 전달의 고속성, 확장성 뿐만 아니라 QOS 보장을 요구하게 되었다. 효과적인 인터넷 백본망을 구현하기 위해 본 논문에서는 Multi-Protocol Label Switching(MPLS)를 고려하고 MPLS 에서 인터넷 Quality Of Service(QOS) 서비스 모델 중 백본망에 적합한 Differentiated Service(DS) 모델을 그대로 제공하기 위해 MPLS 와 DS 의 연동에 대한 문제를 다룬다. 우선 MPLS 에서 QOS 제공을 위한 기능요소를 정성적으로 분석한다. 그리고 두 DS 망 가운데 ATM 기반의 MPLS 망을 두고 있는 경우를 가정하여, 종단대 종단간 DS 제공을 위하여 DS 망과 MPLS 망에서의 시그널링 과정을 제안한다. 즉, DS 의 BB 로부터 SLA 를 위한 신호를 MPLS 의 입구 라우터에서 해석하여 DS Type-Length-Value(TLV)를 만들고 이를 이용하여 Constraint-based Label Distribution Protocol(CR-LDP) 시그널링을 통해 마다 Label-Only-Inferred-PSC LSP(L-LSP)를 설립하여 MPLS 에서 DS QOS 를 그대로 제공한다. 또한 입구 DS BB 로부터의 정보를 MPLS 망을 통해 BB 에게 보낸다.

• The KIPS Transactions:PartC
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• v.18C no.6
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• pp.413-422
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• 2011

Overlay network is a ready-to-use solution to enable new network functionality with existing Internet connectivity intact. This paper introduces a network service which helps users easily compose their own service overlay networks through software-defined networks. We look into the structure of service gateway which enables 1 Gbps packet processing on composed overlay networks. We also provide examples for the way of composing service overlay for support multicast applications. Experiment results carried over the KREONET (Korea Research Environment Open NETwork) show the forwarding performance of the service gateway.

• Journal of Information Processing Systems
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• v.10 no.2
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• pp.176-192
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• 2014

The realization of Wireless Multimedia Sensor Networks (WMSNs) has been fostered by the availability of low cost and low power CMOS devices. However, the transmission of bulk video data requires adequate bandwidth, which cannot be promised by single path communication on an intrinsically low resourced sensor network. Moreover, the distortion or artifacts in the video data and the adherence to delay threshold adds to the challenge. In this paper, we propose a two stage Quality of Service (QoS) guaranteeing scheme called Prioritized Multipath WMSN (PMW) for transmitting H.264 encoded video. Multipath selection based on QoS metrics is done in the first stage, while the second stage further prioritizes the paths for sending H.264 encoded video frames on the best available path. PMW uses two composite metrics that are comprised of hop-count, path energy, BER, and end-to-end delay. A color-coded assisted network maintenance and failure recovery scheme has also been proposed using (a) smart greedy mode, (b) walking back mode, and (c) path switchover. Moreover, feedback controlled adaptive video encoding can smartly tune the encoding parameters based on the perceived video quality. Computer simulation using OPNET validates that the proposed scheme significantly outperforms the conventional approaches on human eye perception and delay.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.1026-1029
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• 2009

Efficient Power consumption is important in sensor networks because charging of deployed sensor nodes is too difficult. So this paper focused on Modified-CBPER reduces energy consumption by reducing CBPER's data announcement ragne, and propose an algorithm to reduce power consumption by additional reduction of data announcement range. Proposed EM-CBPER(Enhanced Modified CBPER) somewhat increases power consumption of data request and data forwarding but it reduces total power consumption by reducing data announcement transmission of account for large quantity on total packet transmission.

• Journal of the Korea Society of Computer and Information
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• v.6 no.3
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• pp.44-49
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• 2001

In general. requirements for QoS are different according to the type of services in wireline and wireless ATM, and real-time video service is more sensitive to cell transmission delay than to cell loss. Existing handoff schemes emphasizing prevention of cell loss had limitations in cell transmission delay to satisfy QoS. In this paper, a novel scheme to transmit ATM cells with low CLP (when CLP = 0) prior to others and discarding cells with high CLP (when CLP = 1) in ATM cell header among cells to be forwarded during handoffs in real-time VBR service is proposed. The proposed scheme is proven to be suitable for the satisfaction of QoS and appropriate for fast handoffs by giving high CLP value to less meaningful MPEG frames through simulations.

• ETRI Journal
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• v.43 no.4
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• pp.674-683
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• 2021

A trust-aware secure routing protocol (TSRP) for wireless sensor networks is proposed in this paper to defend against varieties of attacks. First, each node calculates the comprehensive trust values of its neighbors based on direct trust value, indirect trust value, volatilization factor, and residual energy to defend against black hole, selective forwarding, wormhole, hello flood, and sinkhole attacks. Second, any source node that needs to send data forwards a routing request packet to its neighbors in multi-path mode, and this continues until the sink at the end is reached. Finally, the sink finds the optimal path based on the path's comprehensive trust values, transmission distance, and hop count by analyzing the received packets. Simulation results show that TSRP has lower network latency, smaller packet loss rate, and lower average network energy consumption than ad hoc on-demand distance vector routing and trust based secure routing protocol.