• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.10
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• pp.16-23
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• 2003

In this paper, we propose a new optical hybrid switching system that takes advantage of both Optical Burst Switching (OBS) and Optical Circuit Switching (OCS) technologies. This system classifies incoming IP traffic flows into short-lived and long-lived flows for hybrid switching. For performance analysis, we model the system as a single server queue in a Markovian environment. The burst generation process is assumed to follow a two-state Markov Modulated Poisson Process (MMPP), and the service rate fluctuates based on the number of concurrent OCS sessions. Results of the mean delay and queue size for OBS bursts are derived.

• Biomedical Science Letters
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• v.16 no.3
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• pp.193-196
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• 2010

Multiplex PCR-based short tandem repeat (STR) analysis is considered as a good tool for monitoring bone marrow engraftment after sex-mismatched allogeneic transplantation and provides a sensitive and accurate assessment of the contribution of both donor and/or recipient cells in post-transplantation specimens. Forensic STR analysis and quantitative real time PCR are used to determine the proportion of donor versus recipient each contained within the total DNA. The STR markers were co-amplified in a single reaction by using commercial $PowerPlex^{(R)}$ 16 system and $AmpFISTR^{(R)}$ $Identifiler^{(R)}$ / $Yfiler^{(R)}$ PCR amplification kits. Separation of the PCR products and fluorescence detection were performed by ABI $PRIS^{(R)}$ 3100 Genetic Analyzer with capillary electrophoresis. The $GeneMapper^{TM}$ ID software were used for size calling and analysis of STR profiles. Extracted DNA was quantified by the $Quantifiler^{TM}$ Human DNA / Y Human Male DNA Quantification Kit The intent of this study was to analyze the ratio of donor versus recipient cells in the post-transplant peripheral blood, spleen, lung and kidney specimens. Specimens were taken from the traffic accident male victim who had been engrafted from bone marrow female donor. Blood and spleen specimens displayed female donor DNA profile. Kidney specimen showed male recipient DNA profile. Interestingly, lung tissue showed mixed profiles. The findings of this study indicate that the forensic STR analysis using fluorescence labeling PCR combined with capillary electrophoresis is quick and reliable enough to assess the ratio of donor versus recipient cells and to monitor the mixed chimeric patterns.

• Journal of Korean Society of Transportation
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• v.22 no.2 s.73
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• pp.165-175
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• 2004

본 고는 대전광역시 첨단교통모델도시 건설사업의 일환으로 구축된 DSRC(Dedicated Short Range Communication) 기술을 활용한 교통정보시스템 구축 사례를 소개함을 목적으로 한다. 공공부문에서의 구간정보 수집 및 가공 체계 구축은 본 대전 ITS 사업이 처음이며 더욱이 DSRC 기술을 구간정보 수집에 적용한 최초의 시도이다. 이에 시스템 구축과정에서 적지 않은 쟁점이 도출되었고, 많은 시행착오를 통해 그 해법을 찾아가며 현재 운영중인 시스템을 완공하게 되었다. 노변기지국(RSE)과 차량장치(OBE)간의 통신에 의해 수집된 자료는, 필터링, 검지기 지점정보, 패턴데이터 등과의 자료합성, 평활화, 통계정보 및 패턴정보 생성 등의 과정을 거쳐 구간소통정보가 산출된다. 현재 운영중인 본 시스템은 향후 지속적으로 보완 발전시켜 나가야 하며, 이를 위해 프로브 수집체계 보완, 시스템의 성능평가, 패턴데이터의 적절한 유지관리, 알고리즘의 지속적 발전 등을 향후과제로서 제시하였다. 본 고는 ITS사업에 있어 중요 쟁점중에 한 분야인 소통정보의 가공 절차를 공유함으로써, 관련 분야의 기술개발 촉진과 향후 유사시스템 구축의 시행착오를 줄이는데 기여할 수 있으리라 판단된다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2013.07a
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• pp.15-18
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• 2013

본 논문에서는 교통상황을 실시간으로 반영하여 최적의 이동경로를 제공하는 적응형 내비게이션 시스템을 제안한다. 본 시스템은 세 가지 요소로 구성되어있다. 첫 번째로 도로교통망 중 한 구획의 도로상황정보를 수집하고 공유하는 Traffic Control Center (TCC). 두 번째로 개별적인 도로나 교차로에 설치되어 차량으로부터 도로상황정보를 수집하는 Road Side Unit(RSU). 마지막으로 차량들 간의 망 형성을 위해서 사용되는 Dedicated Short Range Communications(DSRC)를 기반으로 차량에 설치된 단말기가 있다. DSRC를 기반으로 RSU와의 통신하는 단말기는 실시간 도로교통정보를 기반으로 운전자에게 최적의 경로를 제공한다. 이동속도와 같은 교통정보는 단말기에서 측정되고, RSU로 전송된다. RSU는 이 정보를 처리하여 해당 도로의 도로상황지수를 생성하고, 주기적으로 TCC에 전송한다. TCC는 RSU로부터 도로상황지수를 통합하여 TCC의 관할 구획의 모든 차량에 대해 도로교통정보를 만든다. 마지막으로 단말기는 효율적인 경로안내를 위해 최적의 경로를 도출하여 운전자에게 제공한다. 따라서 단말기, RSU, TCC간의 상호작용을 통해 AINS는 동적인 교통상황(정체, 교통사고 등)을 기반으로 새로운 형태의 적응형 지능 내비게이션을 제공할 수 있다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.1
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• pp.30-36
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• 2009

Dedicated Short Range Communication (DSRC) systems in urban areas are used to collect traffic information from vehicles and to provide vehicles with information received from Roadside Equipment (RSE) having a range of 100 meters (m). However, it is not practical to use RSE with a range of 100 m for express highways. In this paper, we expand the standard cell coverage of RSE to 300 m, and adopt fixed relays to cover sites that cannot communicate with the RSE. We demonstrate that the system using the fixed relays is more economical than using only RSE.

• Journal of Trauma and Injury
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• v.25 no.4
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• pp.291-295
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• 2012

Ureteral trauma is rare, accounting for less than 1% of all urologic traumas. However, a missed ureteral injury can result in significant morbidity and mortality. The purpose of this case presentation is to suggest another method for early detection of ureteral injury in blunt traumatic patient. A 47-years-old man was injured in pedestrian traffic accident. He undergone 3-phase abdominal CT initially and had had a short-term follow-up simple. We suspected ureteral injury. Our final diagnosis of a ureteral injury was based on follow-up and antegrade pyeloureterography, he underwent emergency surgery. We detected the ureteral injury early and took a definitive action within 24 hours. In blunt trauma, if abnormal fluid collection in the perirenal retroperitoneal space is detect, the presence of a ureteral injury should be suspected, so a short-term simple X-ray or abdominal CT, within a few hours after initial abdominal CT, may be useful.

• Journal of Korea Society of Industrial Information Systems
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• v.11 no.1
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• pp.69-76
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• 2006

Telematics, which is a compound word of a telecommunication and informatics, provides drivers with useful driving information such as driving path guidance, accident or robbery detection, traffic conditions and other valuable data at real time. This paper proposes and implements how to build a telematics terminal equipped with CDMA and GPS running embedded Linux, to check a vehicle's state through communication between telematics server and vehicle terminals using a cellular phone and to control a vehicle using SMS as shown in Figure 1. In order to do this, we use the SK-VM platform which is mobile terminal platform based on JAVA to design, implement and evaluate it.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.7A
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• pp.973-986
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• 1999

In this paper, we propose MAC protocol that consists of channel access mechanism and transmission mechanism to support effective wireless packet data service. In channel access mechanism, broadcast channel announces status information of random access channel, and mobile station tries random access based on status information. Also, mobile station has access probability to prevent collision increase due to transmission of short message. For effective transmission, mobile station changes transmission rate based on transmission queue status to adapt burst traffic characteristics. In restricted environments of transmission code and bandwidth, proposed protocol shows better performance than cdma2000 system.

• Journal of Communications and Networks
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• v.17 no.3
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• pp.247-255
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• 2015

In this paper, we propose an adaptive time division multiple access based medium access control (MAC) protocol, called bitmap-assisted shortest job first based MAC (BS-MAC), for hierarchical wireless sensor networks (WSNs). The main contribution of BS-MAC is that: (a) It uses small size time slots. (b) The number of those time slots is more than the number of member nodes. (c) Shortest job first (SJF) algorithm to schedule time slots. (d) Short node address (1 byte) to identify members nodes. First two contributions of BS-MAC handle adaptive traffic loads of all members in an efficient manner. The SJF algorithm reduces node's job completion time and to minimize the average packet delay of nodes. The short node address reduces the control overhead and makes the proposed scheme an energy efficient. The simulation results verify that the proposed BS-MAC transmits more data with less delay and energy consumption compared to the existing MAC protocols.

• Journal of Korean Society of Transportation
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• v.23 no.4 s.82
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• pp.71-79
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• 2005

Existing arterial link travel time estimation methods relying on either aggregate point-based or individual section-based traffic data have their inherent limitations. This paper demonstrates the utility of data fusion for improving arterial link travel time estimation. If the data describe traffic conditions, an operator wants to know whether the situations are going better or worse. In addition, some traffic information providing strategies require predictions of what would be the values of traffic variables during the next time period. In such situations, it is necessary to use a prediction algorithm in order to extract the average trends in traffic data or make short-term predictions of the control variables. In this research. a multi-step ahead prediction algorithm using Data fusion was developed to predict a link travel time. The algorithm performance were tested in terms of performance measures such as MAE (Mean Absolute Error), MARE(mean absolute relative error), RMSE (Root Mean Square Error), EC(equality coefficient). The performance of the proposed algorithm was superior to the current one-step ahead prediction algorithm.