• Journal of Korea Society of Digital Industry and Information Management
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• v.5 no.2
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• pp.123-131
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• 2009

Process Control Systems (PCSs) or Supervisory Control and Data Acquisition (SCADA) systems have recently been added to the already wide collection of wireless sensor networks applications. The PCS/SCADA environment is somewhat more amenable to the use of heavy cryptographic mechanisms such as public key cryptography than other sensor application environments. The sensor nodes in the environment, however, are still open to devastating attacks such as node capture, which makes designing a secure key management challenging. Recently, Nilsson et al. proposed a key management scheme for PCS/SCADA, which was claimed to provide forward and backward secrecies. In this paper, we define four different types of adversaries or attackers in wireless sensor network environments in order to facilitate the evaluation of protocol strength. We then analyze Nilsson et al. 's protocol and show that it does not provide forward and backward secrecies against any type of adversary model.

• Information and Communications Magazine
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• v.12 no.8
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• pp.53-64
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• 1995

In this article, criteria and considerations for selecting a domestic Personal Communications Services (PCS) system in Korea are presented and upbanded IS-95 Common Air Interface (CAI) is asserted to be appropriate as a result of evaluation by the criteria. And Shinsegi Telecomm, Inc. (STI) is claimed to be a suitable operator to provide PCS by upbanded IS-95 considering the experiences as the cellular operator adopting IS-95 CDMA technology. The PCS R&D plan and strategies of STI are given and the joint R&D plan with domestic manufacturers to develop PCS systems are explained. The results from R&D so far are mentioned. The PCS network architecture and various services-basic voice service, value-added services and wireless data services-are discussed.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2747-2749
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• 2000

The KEPRI has been developing the medium/small scale Distribution Automation System(DAS) that adopts wireless transmission media for exchanging information between master and remote terminals. It was concluded that Short Message Service(SMS) of Personal Communication Service(PCS) was the best wireless transmission media for the medium/small scale DAS in the last year. However. we had problem that PCS had long transmission delay. Therefore. SMS phones will be substituted with Radio Link Protocol(RLP) modems having transmission delay less than 5 seconds. This paper describes wireless networks for DAS, practical experience.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.26 no.2
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• pp.42-45
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• 2003

본 논문은 무선개인통신(PCS)환경에서 기존의 자원경매다중접속(RAMA)방법이 가지고 있는 단점을 보완할 수 있는 새로운 자원경매다중접속방법(MRAMA)을 제안하기 위한 것이다 제안된 방법은 경매표 개념을 도입하여 슬럿 할당 주기 상에서 경매 슬럿(slot)을 낭비하는 단점을 보완할 수 있으며, 할당 주기마다 갱신되는 경매테이블을 채택하고 선점 및 비선점 우선순위규칙이 혼합된 방법을 활용함으로써 빠르고 유연하게 접속, 핸드오프, 자원할당이 가능해진다. 본 논문에서는 다양한 환경에서의 시뮬레이션을 통해 제안된 MRAMA방법이 기존의 RAMA에 비해 더 향상된 성능을 보이고 있음을 증명한다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.214-217
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• 2001

This paper presents an implementation methodology of common Rf- integrated PCS base station system which, is capable of providing PCS services for 3 PCS carriers concurrently and wireless system performance evaluation data is shown. We have built up a common PCS base station system using a commonization module, which is consisted of a multi-channel combiner, duplexer, LNA, power divider, feeder line, and a common set of antennas. It was shown that the performance of the system within the total 30MHz PCS frequency range is uniformly acceptable and measured signal quality and coverage are equivalent to that of the individual PCS base station. It is expected that PCS carriers are able to save a huge amount of installation and maintenance expenses by installing and sharing this base station system. This paper forms a groundwork for deploying efficient and economical IMT-2000 network.

• Proceedings of the IEEK Conference
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• 2000.06e
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• pp.167-170
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• 2000

In this paper, we develope a intelligent monitoring system of Coastal Ocean Environment based on WWW(World Wide Web) and PCS(Personal Communication System). This system have capability of real time processing of enviromental variable from various sensors. The system is composed of three part. The first part is mathematical modeling of real ocean. The second is construction server for real time web page. And the third is developing the measurement system which has wireless(PCS) interface to server.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.7
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• pp.24-30
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• 2000

In this paper, we proposed an fiber-optic transceivers based on the analog optical transmission techniques of incorporating the SCM (subcarrier multiplexing) and WDM (wavelength-division multiplexing ) method, which can be used to transmission of IMT-2000 and PCS wireless frequency band and analyzed overall those parameters related with fabrication. Especially in the impedance matching network between RF signal and LD, we proposed the method of deriving optimal performance using simulation techniques. In the frequency band of 1.7GHz∼2.25GHz, experimental data for the gain flatness and the noise floor of the optical link were also presented $\pm$1.5dB and -130dBm respectively when the link Rain was 0dB.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.3
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• pp.1-11
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• 1997

Since the radio spectrum is limited, future wireless system will have micro cellular architecture in order to provide multimedia traffic services on personal communicatons network. The small coverage area of micro cellular systems results in frequent hadnoffs and location updates. We focuse on network load and terminal power due to frequent location updates and propose a location tracking scheme using embedded-pager PCS terminals. The proposed scheme is expected to minimize theconsumption of PCS terminal powr and improve the receiving rate of callee because of the power saving mechanism and the embedded-pager PCS terminal. This paper proposes signaling flows among the network elements for the proposed location tracking scheme. The signaling flows are accomodated to not only the existed network architectures but alsothe ATM backbone network arcitecture. To verify the signaling flows, we used petri-Net model. The resutls show that the signaling flows are suitable to our proposed location tracking scheme.

• Journal of information and communication convergence engineering
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• v.6 no.2
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• pp.164-168
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• 2008

Wideband terminal and base station is required to serve not only existing 1st and 2nd generation mobile communication systems but also 3rd generation systems. In this paper, we presents a feasibility study on single feed compact wideband antenna for wireless communication applications including GSM (890-960 MHz), GPS (1575 MHz), DCS (1710-1880 MHz), PCS (1880-1990 MHz), UMTS (1900-2200 MHz), ISM (2400-2480 MHz), IMT2000 and satellite DMB bands. The original antenna was designed for partial discharge detection sensor in high voltage diagnostic system. However, we modified the original prototype to achieve shifted down resonant frequency for wideband wireless communication applications. The experimental result shows good return loss characteristics and radiation patterns except for the total gain at each resonant frequency. The maximum measured gain was 2.45 dBi${\sim}$3.18 dBi at 1710 MHz${\sim}$1880 MHz.

• Journal of information and communication convergence engineering
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• v.7 no.2
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• pp.98-106
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• 2009

Process Control Systems (PCSs) or Supervisory Control and Data Acquisition (SCADA) systems have recently been added to the already wide collection of wireless sensor networks applications. The PCS/SCADA environment is somewhat more amenable to the use of heavy cryptographic mechanisms such as public key cryptography than other sensor application environments. The sensor nodes in the environment, however, are still open to devastating attacks such as node capture, which makes designing a secure key management challenging. In this paper, a key management scheme is proposed to defeat node capture attack by offering both forward and backward secrecies. Our scheme overcomes the pitfalls which Nilsson et al.'s scheme suffers from, and is not more expensive than their scheme.