• Journal of information and communication convergence engineering
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• v.7 no.4
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• pp.465-468
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• 2009

There is to solution the environmental data which the importance is seriously taken into consideration in the the 21st century that is set up whether or not be a welfare society advanced country according to quality of life elevations through environments in question to a preferential assignment for an environmental control will decrease of measures, and be proceeded so as to be urgent. However, shall get measurement of a correct environmental pollution duty and reduction measures stopped on bases of the data which there is reliability, and decrease excessive pollution than what, and may overcome efficiency of waste of cost environmental pollution management. Environmental pollution data collected are regarded as important, and, specially, a collection of environmental data forecast a pollution circle, or to analyze future development is important very at an environmental policy decision or decision making step to be national besides pollution reductions.

• Journal of Communications and Networks
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• v.8 no.4
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• pp.442-450
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• 2006

Inter-operability between heterogeneous radio access technologies (RATs), in the sense of seamless vertical han-dover (VHO) support with common radio resource management (CRRM) functionalities, has recently attracted a significant research attention and has become a prominent issue in standardization fora. In this paper, we formulate the problem of load balancing between cooperative RAT's as a mathematical program and by trading off a pre-defined delay tolerance per request we propose a vertical handover batch processing (VHBP) scheme. To quantify the performance of the proposed VHBP scheme we compare it with a baseline processing scheme, where each VHO request is processed independently under a number of different network scenarios. Numerical investigations reveal significant net benefits of the proposed scheme compared with the baseline, both in terms of achieved load balancing levels but also with regard to the acceptance rate of the VHO requests.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.49 no.3
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• pp.1-11
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• 2012

Data association plays an important role in intelligent systems. This paper presents the Bayesian formulation of data association and its applications to intelligent systems. We first describe the Bayesian formulation of data association developed for solving multi-target tracking problems in a cluttered environment. Then we review applications of data association in intelligent systems, including surveillance using wireless sensor networks, identity management for air traffic control, camera network localization, and multi-sensor fusion.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.137.2-137
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• 2001

We have been developed an intelligent mobile robot with an artificial olfactory function to recognize odours and to track odour source location. This mobile robot also has been installed an engine for speech recognition and synthesis, and is controlled by wireless communication. An artificial olfactory system based on array of 7 gas sensors has been installed in the mobile robot for odour recognition, and 11 gas sensors also are located in the bottom of robot to track odour sources. 3 optical sensors are also included in the intelligent mobile robot, which is driven by 2 D.C. motors, for clash avoidance in a way of direction toward an odour source. Throughout the experimental trails, it is confirmed that the intelligent mobile robot is capable of not only the odour recognition using artificial neural network algorithm, but also the tracking odour source using the step-by-step approach method ...

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.114.4-114
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• 2001

Recently, variety services are more and more developed due to supply of PDA, cellular phone, and etc. Also, a services based on location information are very helpful in traffic, shopping, and emergency. Thus the user position is positively necessary for these services. One of the latest applications in GPS is the E911 call service for wireless phones. In this case, current GPS Navigation accuracy meets the FCC requirements but the hardware size and power consumption of GPS is issued for implementation. And, some case of applications need to snapshot location solution with fast TTFF(Time-To-Fist-Fix) than continuous location solution. The software GPS receiver could be the solution ...

• Proceedings of the IEEK Conference
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• 2003.07a
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• pp.270-273
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• 2003

The design, fabrication, and measured result of a 4.7 GHz differential VCO (Voltage Controlled Oscillator) for a 5.2 GHz WLAN (Wireless Local Area Network) applications is presented. The circuit is designed in a 0.35 mm technology employing three metal layers. The design is based on a fully integrated LC tank using spiral inductors. Measured tuning range is 10% of oscillation frequency with a control voltage from 0 to 3.0 V. Oscillation power of $\square$ 2.3 dBm at 4.63 GHz is measured with 21 mA DC current at 3V supply. The phase noise is $\square$ 104.17 dBc/Hz at 1 MHz offset.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.68-70
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• 2013

Wireless communications based train control system which is operated with a dedicated frequency band is used only on the fixed path. Because of that, the problem arises in the area of efficiency. In this paper, a network access management technique is proposed to make the railway dedicated frequency band accessible by a normal mobile communication users efficiently and safely.

• Proceedings of the KAIS Fall Conference
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• 2011.05a
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• pp.3-6
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• 2011

본 논문에서는 배전지능화시스템과의 정보연계, 미래 지능형전력망 운용 및 태양광, 풍력, 연료전지 등과 같은 신에너지전원의 단지를 효율적으로 유지, 관리하기 위하여, 유 무선 네트워크를 이용하여 원격 감시제어장치를 제작하였다. 이 장치는 한기대 캠퍼스 내에 설치되어 있는 50KW급 태양광전원을 대상으로 1km 정도 떨어져 있는 그린에너지연구실에서 유무선 네트워크를 이용하여 실시간으로 출력되는 전압, 전류데이터를 무선네트워크로 장거리 전송하여, HMI 프로그램인 AutoBase로 실시간 모니터링 하도록 제작하였다. 앞으로 본 논문에서 제안한 원거리 감시제어 장치를 이용하여 원거리에 위치한 대규모 태양광발전단지의 데이터를 무선네트워크 기술로 전송받아 보구슈지를 수행할 수 있는 기반을 마련하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10d
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• pp.245-248
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• 2006

최근 UDP를 이용한 실시간 어플리케이션이 증가하고 있지만, 대부분 혼잡제어를 사용하지 않고 있다. 이러한 문제를 해결하기 위하여 IETF에서는 UDP를 대신하면서 실시간 트래픽 전송을 위하여 혼잡제어 메커니즘을 포함한 DCCP(Datagram Congestion Control Protocol)를 제안하였다. DCCP는 윈도우 기반 흐름제어를 사용하여 실시간 트래픽을 지원하기 위하여 제안된 차세대 전송 프로토콜이다. 본 논문에서는 DCCP의 기본 개념과 혼잡제어 기법을 소개하고, 유선과 무선에서 다양한 전송 프로토콜을 이용하여 DCCP의 성능평가를 한다. DCCP를 기반으로 유선과 무선 네트워크 환경에서 시뮬레이션 성능분석을 위해 Network Simulator 2(NS-2)를 이용한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.9A
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• pp.2282-2288
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• 1998

ATM techniques ar ewidely accepted as a key transport mechanism infiber-based broadband network. However, to keep pace with the rpid emerging wireless high speed market, it is desirable to verify the reliability & daptability of ATM protocol on high error environment. This paper investigates the various ATM cell transfer characteristics over air interface. Though simulation, we analyze their usabilities of HeC mechanism and single-bit error correction algorithm based on ITU-T recommendation. We propose some methods for cell transport improvement over errored environment and investigate their performance for suggested schemes.