• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.2
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• pp.53-59
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• 2009

Integrating a field of transportation and IT is becoming a novel solution to social and economic problems which was previously focused on the investment in infrastructures. It also created new areas of industry such as ITS and telematics. Especially, vehicle communication is being considered very important and DSRC is also important in the field of rational ITS in recent. DSRC OBE has come into wide use through ETCS. In the field of traffic signal control, the research to implement an optimal traffic signal control system using a real-time information of good quality is being carried out and also the study of WISDOM was successfully completed. This paper shows the development of Dynamic-Dilemma zone warning service utilizing WISDOM and the evaluation of a reliability and a practicality through the field test. While the proposed Dynamic-Dilemma warning system transmits an information of signal time optimized by WISDOM, the OBE which receives this information makes dilemma zone based on its location and speed and gives warning to a driver.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.4
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• pp.116-125
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• 2020

Incalculable damage will be incurred if the national infrastructure that provides services using GNSS signals is affected by jamming signals. To prevent this, a nationwide GNSS jamming monitoring network is necessary to detect the occurrence of a jamming signal, determine the type, and properly localize the jammer position. In this paper, 2-D images for live GNSS signals were generated to verify the environment of the jamming signals through the presence and type of GNSS jamming signals at K-City, which are the test beds for self-driving vehicles, and Incheon International Airport. The analysis was also conducted to detect the occurrence of the jamming signals, determine the type, and measure the jamming signal strength. As a result, a CWI type of jamming signal was detected in L2 band at K-City and in L5 band at Incheon International Airport.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.4 s.346
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• pp.38-48
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• 2006

In this paper, we developed a hardware architecture of Reed-Solomon RS(255,239) decoder for the DMB mobile terminals. The DMB provides multimedia broadcasting service to mobile terminals, hence it should have small dimension for low power and short decoding delay for real-time processing. We modified Euclid algorithm to apply it to the key equation solving which is the most complicated part of the RS decoding. We also designed a small finite field divider to avoid the use of large Inverse-ROM table, and it consumed 17 clocks. After synthesis with Synopsis on Samsung STD130 $0.18{\mu}m$ Standard Cell library, the Euclid block had 30,228 gates and consumed 288 clocks, which gave the 25% reduced area compared to other existing designs. The size of the entire RS decoder was about 45,000 gates.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.12
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• pp.9-16
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• 2011

Most of the current mobility management protocols such as MIPv4/6 and its variants standardized by the IETF do not support global seamless handover. This is because they require comprehensive changes of the existing network infrastructure. In this article, we propose a simple mobility management protocol (SMMP) which can support global seamless handover between homogeneous or heterogeneous wireless networks. The idea is that the SMMP employs separate location management function as done in SIP to support global user and service mobility. In addition, the bidirectional tunnels are dynamically constructed to support seamless IP mobility by extending the IEEE 802.21 MIH standards. The detailed architecture and functions of the SMMP have been designed. Finally, the simulation results, using NS-2, show that the proposed SMMP outperforms the existing MIPv6 and HMIPv6 in terms of handover latency, packet loss, pear signal noise ratio (PSNR).

• Journal of the Korea Society of Computer and Information
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• v.17 no.7
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• pp.97-106
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• 2012

Management of biosignal data in mobile devices causes many problems in real-time transmission of large volume of multimedia data or storage devices. Therefore, this research paper intends to suggest an m-Health system, a clinical data processing system using mobile in order to provide quick medical service. This system deployed health system on IP network, compounded outputs from many bio sensing in remote sites and performed integrated data processing electronically on various bio sensors. The m-health system measures and monitors various biosignals and sends them to data servers of remote hospitals. It is an Android-based mobile application which patients and their family and medical staff can use anywhere anytime. Medical staff access patient data from hospital data servers and provide feedback on medical diagnosis and prescription to patients or users. Video stream for patient monitoring uses a scalable transcoding technique to decides data size appropriate for network traffic and sends video stream, remarkably reducing loads of mobile systems and networks.

• Journal of Korea Port Economic Association
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• v.28 no.2
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• pp.113-128
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• 2012

By strengthening the market control and expanding the networks, providers of global logistics are expanding their service scope. Warehouses connects networks to between internal and external warehouses worldwide by using employees. The paper focuses on analyzing the efficiency of the top forty Global Logistics Providers. Therefore, the study classifies the factors which specify the efficiency of a total logistics industry and verified its firmness. Furthermore, the most recent published reports by Logistics Quarterly and Armstrong Association in 2012 was used in order to guarantee credibility of the study. For scope period for analysis, this study utilizes three years of materials, from 2007 to 2010. By applying the DEA Window model and Malmquist, the trend in efficiency and stableness was analyzed. Consequently, the main purpose of the paper is evaluating the efficiency. Also, analyzing its determinants and illustrating a long-term relationship between the annual turnover and the number of Industry Focus/Key Customers was used as output measures. In addition, the number of warehouses worldwide and employees worldwide, of Logistics Providers were used as input measures.

• Journal of Digital Convergence
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• v.15 no.8
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• pp.341-349
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• 2017

CCN proposes that intermediate network nodes on a network path for a transmitted data-packet cache the data-packet. If the nodes receive request packets for the cached data, the nodes can directly respond to the request-packets using the cached data. Since a request-packet can be responded by one of the intermediate nodes on a path of the request-packet, both faster response time and decreased data transmission amount are expected comparing to the existing host centric networking. However, CCN is vulnerable against forgery attacks because data-packet receivers cannot identify a data provider. Hence, a data authentication scheme is essentially needed to make CCN more secure. But such a data authentication process is one of the main causes of CCN-based service delays. This paper first analyzes the problems of a CCN data authentication scheme, then proposes an improved authentication operation scheme for efficiently authenticating data, and finally evaluates its performance.

• Journal of the Korea Society for Simulation
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• v.17 no.3
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• pp.35-44
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• 2008

Facility location problem is an important subject in many areas of modern business environment. In this paper, we deal with uncapacitated and multi-period facility location problem where the object is a maximization of total profit within predetermined cost. We assume that all demand have to be met. Particularly, we represent various types of customer based on four well-known urban spatial structures to represent a spread of customers. Those are concentric zone model, sector model, multiple nuclei model and star model respectively. We apply to the genetic algorithm to simulate a large scaled problem and develop simulator. We analyze both optimal numbers and locations of facilities for each urban structure. Furthermore, we examine the appropriate time to further expansion of the facilities in the planning horizon. The experimental results show that the developed algorithm can be applied effectively to the facility location problem in the various types of urban area.

• Journal of the Society of Disaster Information
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• v.12 no.4
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• pp.358-365
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• 2016

Micro dust is closely related to real life. Especially, the micro dust forecasting system is being implemented from February 2014. Reliability of data through air pollution monitoring network is important. The Ministry of Environment operates 506 air pollution monitoring networks (11 types) to analyze national air quality and establish air policies. However, there is not enough system to confirm and check the site suitability of the measurement site. Therefore, this study analyzes urban space using GIS. Assess the appropriateness and equity of air pollution measurement facilities. The final goal is to reflect the results of the analysis into the Seoul Metropolitan Air Pollution Monitoring Network Installation Plan.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.5
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• pp.173-178
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• 2014

Smart devices linked to high speed networks enable us to obtain location dependent data at anywhere and anytime. In this environment, a wireless data broadcast system can deal with enormous data request from a great number of clients effectively. In order to set up an efficient wireless data broadcast system, various data scheduling and indexing schemes have been proposed. However, a simulation framework to evaluate the schemes is not reported yet. In this paper, we design and develop a simulation framework for a wireless data broadcast system. The developed simulation framework can evaluate quickly a wireless data broadcast system and has scalability to adopt various data scheduling and indexing schemes for wireless data broadcasting.