• 대한전자공학회논문지SD
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• 제44권12호
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• pp.18-24
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• 2007

반도체 공정 기술의 발전으로 인한 개략 배선 지연시간의 증가는 고성능 시스템의 설계를 어렵게 하고 있다. 이 문제를 해결하기 위해 배선에 파이프라인 요소를 삽입하는 방법이 있으나 시스템의 타이밍을 변화시켜 시스템의 기능성을 보장할 수 없다. LIP(Latency Insensitive Protocol)는 임의의 파이프라인 요소의 삽입에 대해 기능성을 보장하지만 처리량이 저하된다. 처리량 저하를 줄이기 위해서는 평면계획 단계에서 처리량을 고려하여 블록을 배치하여야 한다. 이러한 평면계획을 가능하게 하기 위해서 새로운 처리량 계산 방법을 제안하고 평면계획의 비용함수에 적용하였다. 실험 결과, 기존의 휴리스틱 처리량 평가 방법을 적용한 평면계획에 비해 처리량이 평균 16.97% 향상되었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -2
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• pp.661-664
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• 2000

A workflow expresses the How of persons and things related to a business. To improve efficiency of a business, it is important to grasp and evaluate the actual situation of the current business. Till now, researches on workflows have been done almost on once business and these results can not be simply applied to food business. Besides, it is also important how to evaluate a food business workflow with a specific standard. In this paper, we propose a modeling method of food business by using hierarchical Petri net. Then we propose a concept, called throughput, as a standard to evaluate the workflows. Finally we show a method how to compute throughput and meanwhile apply a Petri net tool, Design/CPN, to do simulation of computing throughput. Our simulation result shows the modeling method and computation method of throughput are reasonable and useful.

• 한국통신학회논문지
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• 제38B권1호
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• pp.26-33
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• 2013

저전력, 저가의 초소형 기지국인 펨토셀은 heterogeneous network 의 중요 구성 요소 중 하나이다. 그러나 펨토셀 설치에 따른 셀 구조의 변화는 셀 간 간섭과 signaling overhead 증가와 같은 기술적인 문제를 야기할 수 있다. 이와 같은 기술적인 문제의 해결 방법 중 하나는 펨토셀이 SON(Self-Organized Network)과 같은 기법을 이용하여 자율적으로 전송전력을 조절하는 것이다. 펨토셀은 전송전력 조절을 통해 시스템 throughput을 향상시키거나 overhead를 감소시킬 수 있다. 일반적으로 시스템 throughput을 최대화하기 위한 펨토셀 전송 전력과 시스템 overhead 감소를 위한 펨토셀 전송 전력은 일치하지 않는다. 따라서 본 연구에서는 펨토셀이 시스템 overhead를 감소시키는 동시에 시스템 throughput을 향상시키도록 전송 전력을 조절하는 방법을 제안한다. 모의실험을 통해 제안 기법이 throughput만을 최대화하는 기법에 비하여 시스템 overhead를 41% 감소시키는 것을 확인하였다. 또한 커버리지만을 최적화 하는 기법에 비하여 throughput이 63% 향상되는 것을 확인하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.594-599
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• 2003

This paper proposed to compare and analyze the data throughput of ALOHA and Slotted-ALOHA method which were used to the communication of satellites in an early stage and apply to the data throughput of a transponder in an RFID system. The ALOHA method is the operation priority to a transponder but the Slotted ALOHA method is the operation priority to an reader in an RFID system. Because ALOHA method transmits the data to an reader as a authority of a transponder at random time when generating collisions, therefore, it seems reasonable to conclude that ALOHA method is inefficient for the data throughput and the efficiency of collision interval than Slotted-ALOHA method that synchronizes and controls the transponder in an reader.

• Journal of Communications and Networks
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• 제9권2호
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• pp.118-127
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• 2007

We propose a link adaptation and selection method for the links constituting an orthogonal frequency division multiplexing (OFDM) based wireless relay network. The proposed link adaptation and selection method selects the forwarding, modulation, and channel coding schemes providing the highest end-to-end throughput and decides whether to use the relay or not. The link adaptation and selection is done for each sub-channel based on instantaneous signal to interference plus noise ratio (SINR) conditions in the source-to-destination, source-to-relay and relay-to-destination links. The considered forwarding schemes are amplify and forward (AF) and simple adaptive decode and forward (DF). Efficient adaptive modulation and coding decision rules are provided for various relaying schemes. The proposed end-to-end link adaptation and selection method ensures that the end-to-end throughput is always larger than or equal to that of transmissions without relay and non-adaptive relayed transmissions. Our evaluations show that over the region where relaying improves the end-to-end throughput, the DF scheme provides significant throughput gain over the AF scheme provided that the error propagation is avoided via error detection techniques. We provide a frame structure to enable the proposed link adaptation and selection method for orthogonal frequency division multiple access (OFDMA)-time division duplex relay networks based on the IEEE 802.16e standard.

• 전자공학회논문지A
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• 제32A권2호
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• pp.11-18
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• 1995

Error detection in ARQ(Automatic Repeat Request) protocols is very important in wireless data communication systems. The throughput efficiency of ARQ protocols can be improved by dynamically adapting the protocol packet length so that it approaches the optimum value for throuhput efficiency. In this paper, a simple and novel adaptive packet length allocation method is proposed which transmits the packets with variable length by dyanmically estimating the channel codition. The simulation results show that the average of throughput is improved by 315.4% in the stop-and-wait protocol, 41.4% in the go-back-N protocol and 155.9% in the selective repeat protocol respectively. And the throughput performances of adaptive packet length allocation method approximately approach the theoritically optimal throughput performances.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제5권1호
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• pp.52-67
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• 2011

Network coding is a newly developed technology that can cause considerable improvements in network throughput. COPE is the first network coding approach for wireless mesh networks and it is based on opportunistic Wireless Network Coding (WNC). It significantly improves throughput of multi-hop wireless networks utilizing network coding and broadcast features of wireless medium. In this paper we propose a new method, called FENC, for opportunistic WNC that improves the network throughput. In addition, its complexity is lower than other opportunistic WNC approaches. FENC utilizes division and conquer method to find an optimal network coding. The numerical results show that the proposed opportunistic algorithm improves the overall throughput as well as network coding approach.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.406-409
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• 2000

This paper proposes a method that enables us to implement the recursive least squares (RLS) algorithm at, high throughput rate using fewer processing elements (PEs). It is known that the pipeline processing can provide a high throughput rate. But, pipelining is effective only when enough number of PEs are available. The proposed method achieves high throughput rate using a few PEs. The effectiveness of the proposed method is verified through simulations on programmable digital signal processors (in the following, DSP processors).

• ETRI Journal
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• 제36권1호
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• pp.155-158
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• 2014

This letter presents an antenna design method for an orthogonally-polarized dual antenna for use in mobile stations (MSs) and includes a verification method for improving the link-level throughput performance of an MS that uses a proposed multiple-input multiple-output antenna. The link-level throughput performance of an MS is strongly related to the correlation between antenna branches, which is determined by the cross polarization discrimination of the second branch antenna, both numerically and experimentally.

• 한국통신학회논문지
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• 제31권5A호
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• pp.469-474
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• 2006

본 논문에서는 High Speed Data Packet Access(HSDPA) 시스템의 평균 sector throughput 분석 방법을 개발하였다. 제안하는 성능 분석 방법은 Adaptive Modulation and Coding(AMC)와 scheduling 기법, multi-code 전송의 영향을 반영할 수 있으며, link budget을 응용한 간단한 계산 과정들을 통해, HSDPA의 성능을 분석할 수 있다. 일반적으로, link budget은 셀 coverage를 산출하는 목적으로 사용되었으나, 본 논문에서는 AMC가 적용되는 CDMA 시스템 환경에서 특정 위치에 있는 사용자의 C/I를 계산할 수 있도록 변형하였다. 또한, 개발된 분석 방법을 활용하여, scheduling 기법과 multi-code 전송이 HSDPA 시스템 성능에 미치는 영향을 분석하였다.