• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.5
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• pp.142-155
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• 2019

This study was conducted with the aim of developing a system to collect taxi GPS probe information to prevent link defects and to improve the accuracy of the standard link-based travel speed by determining when to go into and come out the link. For this purpose, a framework and algorithm consisting of a five-step process for standard link-based map matching and individual vehicle travel speed are presented and used it to calculate the average travel speed of the service link. Two on-site surveys of Teheran and Hakdong-ro were conducted to verify the results by the methods proposed in this paper. On the basis of the overall time of the field survey, the deviation in the travel speed was 0.2 km/h and 0.6 km/h, the accuracy was 99% and 96%, and the MAPE(Mean Absolute Percentage Error) was 1% and 4% in Teheran and Hakdong-ro, respectively. These results were more accurate thand those obtained using conventional methodologies without standard links.

• Journal of Advanced Navigation Technology
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• v.16 no.6
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• pp.960-967
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• 2012

Wireless sensor network is used at the environment to obtain nearby information and since such information is transferred through wireless link, it causes unnecessary re-sending and disadvantage of big energy consumption at node. Because of this to select reliable, energy effective link, method of estimating quality on wireless link using RSSI(received signal strength indication), LQI(link quality indication), etc is needed on wireless link. To set up path extending survival time by reducing energy consumption of nodes at the wireless sensor network, the thesis selects with small standard deviation of LQI after obtaining LQI within each path. Additionally, LQI standard deviation routing algorithm is compared based on LQI algorithm such as minimum-LQI, hop-LQI weight and RF output -7dBm. According to the outcome, the algorithm suggested has superior characters such as the number of node, retransmission rate and network life span respectively compared to existing algorithm. Therefore, energy consumption can be efficiently reduced in case that LQI standard deviation routing scheme suggested by this paper is adapted to wireless sensor network.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.2
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• pp.264-271
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• 2017

Link-K message is the Tactical Data Link message standard developed by the Agency for Defense Development which is optimized for the Joint Operation of ROK Armed Force. KMTF message is the standard message format of Battle Management Information System. Interconversion and propagation between these messages are definitely needed to have efficient warfare such as situation data propagation using network, the convergence of collected situation data, common situational awareness, cooperative engagement. Therefore, this study suggests a way of rule and process for format conversion between Link-K and KMTF messages.

• Journal of the Korea Society for Simulation
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• v.28 no.4
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• pp.33-43
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• 2019

Link-16 is a data link that provides joint interoperability to the US Navy, Air Force and NATO. Currently, the military relies entirely on foreign SW and tools for test environment, tactical simulation training and interoperability verification test for Link-16 operation. Therefore, it is necessary to develop Link-16 based operation environment test tool. In this paper, Link-16 network operational performance analysis simulator was developed by analyzing the function of Link-16 foreign tools. It also implements the SIMPLE standard interface for interworking with foreign SW and tools. The functional model for Link-16 network operation performance analysis consists of pre-analysis, real-time operational analysis, and post-analysis functional model. Each functional model test was performed through SIMPLE interworking with foreign SW and tools. Link-16 network operation performance analysis If we replace foreign SW through simulator, we can perform tactical training, network design verification and operation (scenario) verification for our military.

• Journal of information and communication convergence engineering
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• v.10 no.3
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• pp.248-252
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• 2012

The sensor network standard DASH7 was proposed to improve transmission quality and low power communication. Specifications for the standard are currently being developed, so the security specification has not been firmly implemented. However, without a security specification, a network cannot work due to threats from malicious users. Thus we must ensure confidentiality and authentication of data packets by using a cryptography method. To contribute to the DASH7 security specification, this paper shows the implementation results of network and data link layer security by using advanced encryption standard (AES) counter with CBC-MAC (CCM) over CC430 sensor nodes.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2008.04a
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• pp.79-82
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• 2008

웹크롤러는 웹페이지 내의 URL링크를 추적하여 다른 문서를 수집한다. 국내의 상당수 웹사이트는 웹 표준에 맞지 않는 링크방식으로 웹문서를 연결하고 있다. 일반적인 웹크롤러는 링크의 비표준적인 사용을 가정하지 않기 때문에 이러한 문서는 수집할 수 없다. 비표준적인 링크가 가능한 것은 사용자의 실수에 강인한 마크업 언어인 HTML에 자바스크립트 기능이 추가되면서 자바스크립트의 변칙적인 사용이 허용되었기 때문이다. 본 논문에서는 230여개의 웹사이트를 조사하여 기존 웹크롤러에서 해결하지 못한 링크 추출 문제를 찾아내고, 이를 수집하기 위한 알고리즘을 제안한다. 또한 자바스크립트 문제 해결을 위한 무거운 자바스크립트 엔진을 대신하여 필요한 기능만으로 구성된 모듈을 사용함으로써 효율적인 문서 수집기 모델을 제안한다.

• Journal of Satellite, Information and Communications
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• v.3 no.2
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• pp.7-12
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• 2008

The study discussed the link analysis for the Ka band satellite broadcasting service in Korea with respect to the transmission schemes based on the DVB-S2 standard. To analyze the effect of the rain fading to the link budget, we estimated the rain attenuation from the measured rainfall intensity in Korea. We analyzed the link budget for the Ka band transponders of Koreasat-3, and DirecTV BSS-99W, and showed the possible link availability with the DVB-S2 transmission schemes for each transponder. Based on the link analysis of the available satellites with the Ka band transponders, we suggested the required EIRP for the satellite which will be employed for the Ka band satellite broadcasting service in Korea.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.6
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• pp.1063-1068
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• 2008

BACnet(Building Automation and Control Networks) is a standard data communication protocol specifically designed for building automation and control systems, BACnet provides six options for data link layer protocols and these six data link layer options can be applied with various wired transmission media. Recently wireless technology prevails in automation area. ZigBee is an IEEE 802.15.4 based standard communication protocol for low-rate wireless personal area networks. In this study, we propose a BACnet over ZigBee model that adopts ZigBee communication channel as a wireless data link layer protocol in a BACnet-based communication network system. The technology proposed in this paper can expand the BACnet application using the advantages of wired and wireless integrated network solution.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.2
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• pp.218-226
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• 2010

The tactical data-link is useful to exchanging automatic information and controling command in combat environment. This is a essential factor of interoperability in the future combat situation of network centric warfare. In a aspect of a weapon system development, Modeling & Simulation can save expense. HLA RTI is a standard communication protocol in M&S. So, we suggest that Link Simulator connect tactical data-link through RTI. This simulator has the interoperability between M&S and tactical data-link, the reusability through adabing M&S framework, and the wide usability by automatic engagement function.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.3
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• pp.42-49
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• 2013

A simultaneous bidirectional inductively-coupled link is presented. In the conventional inductively-coupled link, data can be bidirectionally transmitted through channel, however not simultaneously. We propose simultaneous bidirectional link for higher data rate with effective echo cancellation technique. Each chip performs TX-mode and RX-mode simultaneously. Instead chip stacking for test, similar test enviroment is realized in a single chip that is fabricated in a $0.13-{\mu}m$ standard CMOS technology.