• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(1)
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• pp.37-40
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• 2000

Multi Protocol Label Switching (MPLS) is a high performance method for forwarding packets (frames) through a network. It enables routers at the edge of a network to apply simple labels to packets (frames). we use MPLS in the core network for internet. MPLS provide high speed switching and traffic engineering in MPLS domain but at the Label Edge Router(LER) there is frequently cell discarding via congestion and buffer management method. It is one of the most important reasons retransmission and congestion. In this paper we propose advanced LER scheme that provide less cell loss rate also efficient network infrastructure.

• 조명전기설비학회논문지
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• 제13권4호
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• pp.109-119
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• 1999

스위치드 리럭턴스 전동기(SRM)는 상대적으로 낮은 가격, 간단하고 견고한 구조, 제어의 용이성과 고효율을 가지기 때문에 가변속 구동에서 점점 응용범위가 확대되고 있다. 본 논문에서 신경망이론은 퍼지-신경망 제어기의 소속함수와 퍼지규칙을 결정하는데 사용하였으며, 신경망 에뮬레이터는 SRM의 전방향 동특성을 모사하는데 사용하였다. 에뮬레이터의 역전파 오차는 퍼지-신경망 제어기의 소속함수와 퍼지규칙을 개선하는 경로를 제공한다. 32비트 DSP(TNS329C31)는 고속연산과 퍼지-신경망 제어 알고리즘을 실현하는데 사용하였다. 시뮬레이션과 실험결과는 부하변화의 경우 제안된 제어방법이 속도응답에서 종래의 방법보다 우수하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1113-1114
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• 2011

This paper is proposed design of high performance controller of SynRM drive using FNN and NNC. Also, This paper is proposed of designing fuzzy neural network controller(FNNC) which adopts the fuzzy logic to the artificial neural network(ANN). FNNC combines the capability of fuzzy reasoning in handling uncertain information and the capability of neural network in learning from processes. This controller is controlled speed using FNNC and model reference adaptive fuzzy control(MFC), and estimation of speed using ANN. The performance of proposed controller was demonstrated through response results. The results confirm that the proposed controller is high performance and robust under the variation of load torque and parameters.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2007년도 춘계종합학술대회
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• pp.83-86
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• 2007

디지털 계측기를 인터넷에 접속하여 원격지에서 검 교정을 하기 위해서는 계측기의 CPU 사용률이 많은 일반 서버와는 다른 임베디드 운영체제를 이용한 고속 전용서버가 필요하다. 본 연구는 웹 기반 원격 검 교정 시스템을 위한 고속 네트워크 모듈을 구현하는 목적이며 인터넷을 통해 디지털 계측기를 원격으로 검 교정을 하고, 고속 네트워킹을 위해 TCP/IP Offload Engine 처리와 임베디드 TCP/IP 스택인 LwIP를 개선하였다.

• IEIE Transactions on Smart Processing and Computing
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• 제3권4호
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• pp.212-220
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• 2014

The current cellular communications are optimized for low mobility users, meaning that their performance is degraded at high speed. Therefore, passengers in a high-speed train experience very poor radio link quality due to the significantly large number of simultaneous handovers. In addition, wireless data traffic is expanding exponentially in trains, subways and buses due to the widespread use of smartphones and mobile devices. To solve the inherent problem of cellular communication networks and meet the growing traffic demand, this paper proposes the mobile hotspot network of a millimeter-wave communication system as a mobile wireless backhaul. This paper describes the physical layer design of uplink and downlink in the proposed system, and the performances of uplink and downlink are evaluated under Rician fading channel conditions. The implemented baseband prototype of the proposed millimeter-wave communication modem is presented. This system can provide a Gbps data rate service in high-speed trains carrying hundreds of wireless Internet users.

• 마이크로전자및패키징학회지
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• 제20권4호
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• pp.69-74
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• 2013

In this paper, the impact of integrating large number of I/O (Input-Output) and Core power Delivery Network (PDN) on a 6 layers Flip-Chip Ball Grid Array (FCBGA) package is investigated. The impact of core induced supply noise on high-speed I/O interfaces, and high-speed I/O interface's supply noise coupling to adjacent high-speed I/O interfaces' jitter impact are studied. Concurrent stress validation software is used to induce SSO noise on each individual I/O interfaces; and at the same time; periodic noise is introduced from Core PDN into the I/O PDN domain. In order to have the maximum coupling impact, a prototype package is designed to merge the I/O and Core PDN as one while impact on jitter on each I/O interfaces are investigated. In order to understand the impact of the Core to I/O and I/O to I/O noise, the on-die noise measurements were measured and results were compared with the original PDN where each I/O and Core PDN are standalone and isolated are used as a benchmark.

• 한국정보통신학회논문지
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• 제10권6호
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• pp.1038-1044
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• 2006

초고속 통신망에서 터널링 기법은 네트워크 인증 및 데이터의 보안 지원에 있다. 이를 위해 IPSec, SOCKS V5 및 GRE 터널링 프로토콜 등을 사용하고 있다. 본 논문은 초고속 통신망에서 특정 IP 대역에 대하여 라우팅 루트를 변경시켜 유해 서비스 접속 차단 및 이용자 Needs에 따라 특정 서비스에 대한 라우팅 루트를 변경시켜 이용자가 원하는 선택적인 서비스 제공 기반을 구현하고자 하였다. 따라서 GRE프로토콜을 이용하여 GRE의 동작 원리를 측정 분석하고, 그 결과를 접속 제어 및 인증 기반 서비스에 적용하고자 한다.

• 한국정보통신학회논문지
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• 제11권6호
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• pp.1077-1082
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• 2007

디지털 계측기를 인터넷에 접속하여 원격지에서 검 교정을 하기 위해서는 계측기의 CPU 사용률이 많은 일반 서버와는 다른 임베디드 운영체제를 이용한 고속 전용서버가 필요하다. 본 연구는 웹 기반 원격 검 교정 시스템을 위한 고속 네트워크 모듈을 구현하는 목적이며 인터넷을 통해 디지털 계측기를 원격으로 검 교정을 하고, 고속 네트워킹을 위해 TCP/IP Offload Engine 처리와 임베디드 TCP/IP 스택인 LwIP를 개선하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.2010-2016
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• 2009

Before introducing high speed train, train signal system was operated passively depending on a driver by signal lamp display. Now it is changing to onboard signaling system because of train speed increased(conventional track is 230km/h, high speed track is 380km/h), high speed. low speed freight train operation mixed, operation for high speed train in conventional track and dense operation. ie. ETCS(European Train Control System) Level 1 is introducing. Also, in case of high speed train, the train control system of France was introduced and has operated from 2004, now we have a difficulty for rising speed more than 300km/h because of commercial operation speed limited as 300km/h. Therefore, it need to establish the train control technique according to trackside surroundings and develope standard system like European ERTMS/ETCS, China CTCS(Chinese Train Control System), Japan D-ATC(Digital Automatic Train Control). In this paper, we derive the systematization method for Korea train technique by network-oriented, information-oriented, intelligence-oriented and combination-oriented corresponding train development direction. Proposed method has a merit to prevent cross by mixed operation with existing system and improvement after validity demonstration and system development and supply train system to meet user requirement in exporting.

• Journal of Communications and Networks
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• 제9권4호
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• pp.394-401
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• 2007

High speed all optical network is a viable option to satisfy the exponential growth of internet usage in the recent years. Optical networks offer very high bit rates and, by employing technologies like internet protocol over wavelength division multiplexing(IP-over-WDM), these high bit rates can be effectively utilized. However, failure of a network component, carrying such high speed data traffic can result in enormous loss of data in a few seconds and persistence of a failure can severely degrade the performance of the entire network. Designing IP-over-WDM networks, which can withstand failures, has been subject of considerable interest in the research community recently. Most of the research is focused on the failure of optical links in the network. This paper addresses the problem of designing IP-over-WDM networks that do not suffer service degradation in case of a single link failure. The paper proposes an approach based on the framework provided by a recent paper by M. Kurant and P. Thiran. The proposed approach can be used to design large survivable IP-over-WDM networks.