Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
The Journal of The Korea Institute of Intelligent Transport Systems
Journal Basic Information
Journal DOI :
The Korea Institute of Inteligent Transport Systems
Editor in Chief :
Volume & Issues
Volume 9, Issue 6 - Dec 2010
Volume 9, Issue 5 - Oct 2010
Volume 9, Issue 4 - Aug 2010
Volume 9, Issue 3 - Jun 2010
Volume 9, Issue 2 - Apr 2010
Volume 9, Issue 1 - Feb 2010
Selecting the target year
Methodology for Selecting Traffic Safety Warning Messages using Analytical Hierarchical Process(AHP)-based Multi-Criteria Value Function
Kim, Tai-Jin ; Oh, Cheol ; Oh, Ju-Taek ;
The Journal of The Korea Institute of Intelligent Transport Systems, volume 9, issue 2, 2010, Pages 1~11
The provision of warning information on upcoming hazards leading to potential crash occurrence is a significant countermeasure to prevent crashes on the highway. This study presents a methodology for selecting more effective warning messages using a multi-criteria value function. The understandability, preference level, and message reading time were used as measures of effectiveness (MOE) for messages. Expert judgements were incorporated into the value function by analytical hierarchical process (AHP) technique. Field experiments to evaluate the warning messages were conducted in a testbed section on the Jungboo-Naeryuk freeway. The proposed methodology would be a useful tool to support the design of various traffic information messages.
Value Analysis of User Satisfaction by VMS Traffic Information Using Contingent Value Method
Yeon, Bok-Mo ; Hong, Ji-Yeon ; Lee, Su-Beom ; Lim, Joon-Bum ; Moon, Byeong-Sup ;
The Journal of The Korea Institute of Intelligent Transport Systems, volume 9, issue 2, 2010, Pages 12~22
The variable message sign(VMS) is a facility to smoothen traffic flows and enable safe passing by providing real-time necessary information on roads, weather, transportation, and traffic regulations. The VMS also solves a feeling of uneasiness and gives a sense of psychological security by providing information to drivers. However, the VMS has a strong character of being a non-market product but a public product, so it has not normally been evaluated for its value. This research has evaluated a value of satisfaction level for traffic information users, using a contingent valuation method(CVM). As a result of evaluating the value of satisfaction level for users through division into an urban roadway and an urban highway for the cities where an intelligent transportation system(ITS) has been established, the urban highway had a value of 96.7 won/system and the urban roadway had a value of 76.3 won/system.
Accident Reduction Effects by year After Installation of Red Light Cameras
Kim, Tae-Young ; Park, Byung-Ho ;
The Journal of The Korea Institute of Intelligent Transport Systems, volume 9, issue 2, 2010, Pages 23~32
Because ROTA(road traffic authority) analyzes the effects of accident reduction based on the data of 1-year after installation of RLC(red light camera), study of accident reduction effects over year after the installation of RLC is very short. This study deals with the traffic accident reduction during 3 years after the installation of RLC. The objective is to analyze the effects of accident reduction by year using EB method. In pursuing the above, the study uses the 951 accident data occurred at the 20 intersections which RLC are installed. The main results analyzed are as follows. First, the safety performance function (SPF) has been developed by the Poisson regression models which are statistically significant. Second, the results of an Empirical Bayes(EB) analyses showed that the accidents were reduced by the range from 2.73 to 38.75% after 1 year, from 6.85 to 47.36% after 2 year, and from 6.04 to 39.31% after 3 year from the installation of RLC.
An Application of Sampling to Determine a Proper Rate of Probe Vehicles for Macroscopic Traffic Flow Monitoring Indices
Shim, Jung-Suk ; Heo, Hyun-Moo ; Eom, Ki-Jong ; Lee, Chung-Won ; Ahn, Su-Han ;
The Journal of The Korea Institute of Intelligent Transport Systems, volume 9, issue 2, 2010, Pages 33~40
In this paper, we consider three macroscopic traffic flow monitoring indices, Travel Time Index(TTI), Acceleration Noise(AN) and Two Fluid(TF) and investigate how to determine a proper rate of probe cars for producing reliable values of these indices. For the analysis, we use classical sampling theories and provide numbers of probe rates using simulation data.
A Design of Multi-band Antenna using asymmetric Bow-tie structure
Jang, Jeong-Seok ; Kim, Dae-Woong ; Choi, Yong-Gyu ; Hong, Ui-Seok ;
The Journal of The Korea Institute of Intelligent Transport Systems, volume 9, issue 2, 2010, Pages 41~50
In this paper, a multi-band antenna with novel structure for mobile communications is designed and fabricated. The proposed antenna has the Multi-band antenna characteristics by two common-grounded slots with different size and angle. In order to reduce size and to enhance the gain of the antenna, a reflector is consisted of chokes on the three sides. It is optimized by using the CST Microwave Studio commercial software based on the FIA(Finite Integration Algorithm) and PBA(Perfect Boundary Approximation), and then the fabricating and measuring is practiced. As a result of measurement, the reflection coefficient is less than -11 dB(VSWR < 1.8) and the gain of antenna is more than 6dBi at 824~894MHz and 1885-2500MHz.
Output Power Back-Off (OPBO) Based Asymmetric Doherty Power Amplifier
Chun, Sang-Hyun ; Jang, Dong-Hee ; Kim, Ji-Yeon ; Kim, Jong-Heon ;
The Journal of The Korea Institute of Intelligent Transport Systems, volume 9, issue 2, 2010, Pages 51~59
In this paper, we propose an inverted type asymmetric Doherty amplifier with optimized efficiency characteristic in wanted output power back-off (OPBO) range according to peak to average power ratio of input signal In order to obtain optimized efficiency of the asymmetric Doherty amplifier in wanted OPBO, peak power ratio between main amplifier and peaking amplifier was determined and then impedance of 90 degrees impedance transformer was obtained by peak power ratio. The offset line length and peak dividing ratio of the asymmetric Doherty amplifier were also calculated. From the measurement results, the proposed amplifier has achieved 40 % drain efficiency and -35 dBc adjacent channel leakage ratio at the average output power of 48.7 dBm for CDMA 2000 1x 3-FA test signal.
A Study on Visible Light Communication with Turbo Coded OFDM for Intelligent Transport Systems
Koo, Sung-Wan ; Kim, Jin-Young ;
The Journal of The Korea Institute of Intelligent Transport Systems, volume 9, issue 2, 2010, Pages 60~67
In the ubiquitous age, applications of wireless personal area network (WPAN) technology using LEDs are in progress. However, visible light communications (VLC) using the LEDs have weakness which deteriorate performance of communication because of multi-path fading that occurs propagation delay by interior walls or other things in indoor environments. In this paper, orthogonal frequency division multiplexing (OFDM) scheme is adapted to decrease multi-path fading and multi-path dispersion and to provide high speed data transmission. Besides, to reduce information losses caused by optical noise (incandescent lamps, fluorescent lamps, sunbeam etc.) also proposed channel coding using turbo codes. The encoding and decoding of the proposed system is described, and simulation results are analyzed. We can know that performance of proposed system is increased about 4 [dB] through the simulation results. Also, when the system take doppler effect, the system performance worsened.
Channel Capacity Analysis of SSW Technique in Wireless Channels for ITS System
Kim, Joo-Chan ; Bae, Jung-Nam ; Kim, Jin-Young ;
The Journal of The Korea Institute of Intelligent Transport Systems, volume 9, issue 2, 2010, Pages 68~74
In this paper, we analyze and simulate the channel capacity of a spread spectrum watermarking (SSW) technique in wireless fading channel to apply ITS system. Channel capacity analysis causing minimum effect to existing system is required necessary to apply SSW technique. We derive the channel capacity as a closed-form approximation formula in Rayleigh and Rician fading channel model. The numerical results are demonstrated and good approximated results are reported.
A case study on road traffic accident prevention and opportunity costs by means of local accident investigation
Jung, Yong-Ki ; Choe, Byong-Ho ;
The Journal of The Korea Institute of Intelligent Transport Systems, volume 9, issue 2, 2010, Pages 75~86
The objective of this study is to suggest the process and method of local accident investigation for local authorities with a view to efficient and effective managing traffic accidents. With a project city selected accident-type maps, accident lists, accident diagrams, priority of black-spots/-lengths, site visits, remedial measures, opportunity costs, monitoring etc. are taken into consideration, by using accident data in the last 3 years. Analyzed are accident savings to be expected when applying technical, organizational, and administrative processes attached to local accident investigation.
Efficient Distributed Allocation Method of Data Replica in VANET
Shim, Kyu-Sun ; Lee, Myong-Soo ; Lee, Sang-Keun ;
The Journal of The Korea Institute of Intelligent Transport Systems, volume 9, issue 2, 2010, Pages 87~95
A Vehicular Ad-Hoc Network (VANET) is form of the Mobile Ad-hoc Network (MANET) to provide temporary communication among vehicles via wireless links. In VANET, the vehicle is one of the nodes in networks and communicates with each other. However, the wireless links disconnect very frequently, because vehicles have mobility and move freely. The reason why data accessibility degrades is that disconnection occurs frequently. To improve data accessibility, data replica allocation methods that made group to allocate data replica have proposed in MANET. However, those are not suitable because it is difficult to maintain stable links among the nodes moving fast by centralized group. In this paper, we proposed TBG (Tree Based Grouping) to allocate data replica with the distributed grouping method. Each node has own TBG and allocates data replica based on stability of links to improve data accessibility. The experiment demonstrates that the proposed method outperforms traditional methods in term of data accessibility.
Performance of Space-Time Trellis Codes with Minimum Hamming Distance Mapping on Fast Fading Channels
Jin, Ik-Soo ;
The Journal of The Korea Institute of Intelligent Transport Systems, volume 9, issue 2, 2010, Pages 96~103
This paper studies the performance of STTC with minimum Hamming distance (MHD) mapping in order to improve the bit error rate (BER) performance. Unfortunately, the MHD mapping used in trellis coded modulation (TCM) or multiple trellis coded modulation (MTCM) cannot be directly applied to STTC because the trellis structure of STTC is generally different from that of TCM or MTCM. Therefore, we need a simple modification to apply the MHD mapping concept in STTC. The core of the modification assigns information bits with a Hamming distance in proportion to the sum of the Euclidean distance to trellis branch of STTC. To the best knowledge, this combination has not been considered yet. The BER performance is examined with simulations and the performance of MHD mapping is compared to that of well known natural mapping and Gray mapping on both fast Rayleigh as well as fast Rician fading channels. It is shown that the performance of MHD mapping is much better than that of natural mapping or Gray mapping over fast Rician fading channels, especially.
A Study on User Authentication for Wireless Communication Security in the Telematics Environment
Kim, Hyoung-Gook ;
The Journal of The Korea Institute of Intelligent Transport Systems, volume 9, issue 2, 2010, Pages 104~109
In this paper, we propose a user authentication technology to protect wiretapping and attacking from others in the telematics environment, which users in vehicle can use internet service in local area network via mobile device. In the proposed user authentication technology, the packet speech data is encrypted by speech-based biometric key, which is generated from the user's speech signal. Thereafter, the encrypted data packet is submitted to the information communication server(ICS). At the ICS, the speech feature of the user is reconstructed from the encrypted data packet and is compared with the preregistered speech-based biometric key for user authentication. Based on implementation of our proposed communication method, we confirm that our proposed method is secure from various attack methods.