• Title/Summary/Keyword: Traffic-sensitive

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Development of Estimation Model of Trip Generation Model and Trip Distribution Model Reflecting Coefficient of Accessibility (접근성 변수를 반영한 통행발생 및 통행분포모형 개발)

  • Jeon, Yong-Hyun;Rho, Jeong-Hyun;Jang, Jun-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.6
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    • pp.576-584
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    • 2017
  • Traffic demand prediction result is a primary factor for decision making such as the traffic planning and operation. The existing traffic demand prediction 4-step model only covers the trip between the origin and the destination, and not the demand followed by the accessibility improvement, due to the characteristic of this model. Therefore, the purpose of this research is to improve the limitations of the existing model by developing the inter-city trip generation and trip distribution model with more accessibility. After calculating of the trip generation and trip distribution model with more accessibility, the sign of the accessibility coefficient was positive. Commuting was the most insensitive indicator, affected by external factors among the other trip purposes. The leisure trip was the most sensitive, affected by the trip fee. According to the result of comparison with each of estimated model and observational data, it was certain that the reliability and assumption of the model have been improved by discovering the reduced weighted average error rate, Root Mean Square Error (RMSE) and total error through the model with more accessibility compared with the existing one.

Development of Left Turn Response System Based on LiDAR for Traffic Signal Control

  • Park, Jeong-In
    • Journal of the Korea Society of Computer and Information
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    • v.27 no.11
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    • pp.181-190
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    • 2022
  • In this paper, we use a LiDAR sensor and an image camera to detect a left-turning waiting vehicle in two ways, unlike the existing image-type or loop-type left-turn detection system, and a left-turn traffic signal corresponding to the waiting length of the left-turning lane. A system that can efficiently assign a system is introduced. For the LiDAR signal transmitted and received by the LiDAR sensor, the left-turn waiting vehicle is detected in real time, and the image by the video camera is analyzed in real time or at regular intervals, thereby reducing unnecessary computational processing and enabling real-time sensitive processing. As a result of performing a performance test for 5 hours every day for one week with an intersection simulation using an actual signal processor, a detection rate of 99.9%, which was improved by 3% to 5% compared to the existing method, was recorded. The advantage is that 99.9% of vehicles waiting to turn left are detected by the LiDAR sensor, and even if an intentional omission of detection occurs, an immediate response is possible through self-correction using the video, so the excessive waiting time of vehicles waiting to turn left is controlled by all lanes in the intersection. was able to guide the flow of traffic smoothly. In addition, when applied to an intersection in the outskirts of which left-turning vehicles are rare, service reliability and efficiency can be improved by reducing unnecessary signal costs.

QoS Guaranteed MAC protocol in Ubiquitous Sensor Networks (USN에서 QoS보장을 위한 MAC 프로토콜)

  • Kim, Seong-Hun;Goh, Sun-Bok;Lee, Seung-Keun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.05a
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    • pp.513-516
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    • 2008
  • The sensor node's performance is expected to be improved and the price will be largely decreased. As USN-applied field is expanded, multiple application services are expected to be provided through one USN soon. Multiple applications be required a periodic data reporting, consecutive information monitoring, event-driven data and query-based data as the data pattern that USN is delivered. Accordingly, the mechanism which can assure QoS according to each data characteristic is required. In this paper, A proposed protocol apply the duty cycle of S-MAC protocol variably and flexible according QoS level. This method largely reduces the delay on the delay-sensitive traffic, while keeping the energy efficiency.

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Comparison of the Symmetry of Buttock Pressure during Simulated Driving between Heathy Adults and Patients with Stroke

  • Shin, Hwa-Kyung;Lee, Du-Hwan
    • The Journal of Korean Physical Therapy
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    • v.29 no.4
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    • pp.218-222
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    • 2017
  • Purpose: Driving is an important activity that is affected by various motor and cognitive deficits after stroke. On the other hand, there is no standard screening tool to evaluate the sitting asymmetry during driving, which is the stereotyped postural characteristic observed in patients with stroke. Therefore, this study compared the buttock pressure during simulated driving between healthy adults and patients with stroke. Methods: Ten post-stroke patients and ten healthy subjects participated in the experiment. The participants experienced simulated driving of 6.1 km during approximately 5 minutes for adaptation. The driving scenario consisted of 3.5 km urban traffic conditions, 10 km straight highway, and 7 km curved or hilly rural roads. Force sensitive application (FSA) was used to analyze the distribution of the buttock pressure on the driver's seat. The symmetry index (SI) was determined using the average buttock pressure of each side of the buttock. The closer SI is to zero, the higher the symmetry of buttock pressure. Results: These studies showed that the SI of healthy subjects was significantly closer to zero than that of the stroke patients. Conclusion: The buttock pressure of the stroke patients showed more asymmetry than that of the healthy subjects during simulated driving. Therefore, a therapeutic approach is needed for symmetrical sitting to improve the driving performance.

A Numerical Algorithm for Evaluating Progression Efficiency along Coordinated Arterials Using Shock Wave Theory (충격파이론을 응용한 간선도로 신호연동화의 효율 평가를 위한 알고리즘의 개발)

  • Kim, Young-Chan;Baek, Hyon-Su
    • Journal of Korean Society of Transportation
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    • v.17 no.2
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    • pp.83-90
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    • 1999
  • A computer algorithm is presented that evaluate the performance of coordinated signal timing plans for the signalized arterials. The procedures calculating delay and stops are based on Michalopoulos's analytical model derived from shock wave theory. The delay-offset relationship predicted from the algorithm produced consistent results with the delays venerated by TRANSYT-7F. From performance test, the delays estimated using the proposed a1gorithm are shown to be sensitive to the quality of progression as well as to traffic demand, link length, and turning flow ratio from upstream signal.

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Forensic STR Analysis of Mixed Chimerism after Allogeneic Bone Marrow Transplantation

  • Eom, Yong-Bin
    • 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.

Variability analysis on modal parameters of Runyang Bridge during Typhoon Masta

  • Mao, Jian-Xiao;Wang, Hao;Xun, Zhi-Xiang;Zou, Zhong-Qin
    • Smart Structures and Systems
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    • v.19 no.6
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    • pp.653-663
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    • 2017
  • The modal parameters of the deck of Runyang Suspension Bridge (RSB) as well as their relationships with wind and temperature are studied based on the data recorded by its Structural Health Monitoring System (SHMS). Firstly, frequency analysis on the vertical responses at the two sides of the deck is carried out to distinguish the vertical and torsional vibration modes. Then, the vertical, torsional and lateral modal parameters of the deck of RSB are identified using Hilbert-Huang Transform (HHT) and validated by the identified results before RSB was opened to traffic. On the basis of this, the modal frequencies and damping ratios of RSB during the whole process of Typhoon Masta are obtained. And the correlation analysis on the modal parameters and wind environmental factors is then conducted. Results show that the HHT can achieve an accurate modal identification of RSB and the damping ratios show an obvious decay trend as the frequencies increase. Besides, compared to frequencies, the damping ratios are more sensitive to the environmental factors, in particular, the wind speed. Further study on configuring the variation law of modal parameters related with environmental factors should be continued.

A Hybrid Simulation Technique for Cell Loss Probability Estimation of ATM Switch (ATM스위치의 쎌 손실율 추정을 위한 Hybrid 시뮬레이션 기법)

  • 김지수;최우용;전치혁
    • Journal of the Korean Operations Research and Management Science Society
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    • v.21 no.3
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    • pp.47-61
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    • 1996
  • An ATM switch must deal with various kinds of input sources having different traffic characteristics and it must guarantee very small value of cel loss probability, about 10$^{8}$ -10$^{12}$ , to deal with loss-sensitive traffics. In order to estimate such a rate event probability with simulation procedure, a variance reduction technique is essential for obtaining an appropriate level of precision with reduced cost. In this paper, we propose a hybrid simulation technique to achieve reduction of variance of cell loss probability estimator, where hybrid means the combination of analytical method and simulation procedure. A discrete time queueing model with multiple input sources and a finite shared buffer is considered, where the arrival process at an input source and a finite shared buffer is considered, where the arrival process at an input source is governed by an Interrupted Bernoulli Process and the service rate is constant. We deal with heterogeneous input sources as well as homogeneous case. The performance of the proposed hybrid simulation estimator is compared with those of the raw simulation estimator and the importance sampling estimator in terms of variance reduction ratios.

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Adaptive Online Bandwidth Management Algorithms for Multimedia Cellular Networks (멀티미디어 셀룰러 네트워크 상에서의 효율적인 온라인 대역폭 관리기법에 대한 연구)

  • Kim Sung-Wook
    • The KIPS Transactions:PartC
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    • v.13C no.2 s.105
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    • pp.171-176
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    • 2006
  • Bandwidth is an extremely valuable and scarce resource in a wireless network. Therefore, efficient bandwidth management is necessary in order to provide high qualify service to users with different requirements in a multimedia wireless/mobile network. In this paper, we propose an on-line bandwidth reservation algorithm that adjusts bandwidth reservations adaptively based on existing network conditions. The most important contribution of our work is an adaptive algorithm that is able to resolve conflicting performance criteria - bandwidth utilization, call dropping and call blocking probabilities. Our algorithm is quite flexible, is responsive to current traffic conditions in cellular networks, and tries to strike the appropriate performance balance between contradictory requirements for QoS sensitive multimedia services.

Differentiated Services Based Admission Control and Multi Path Routing Algorithm for IPv6

  • Farooq, Muhammad Omer;Aziz, Sadia
    • Journal of Information Processing Systems
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    • v.5 no.2
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    • pp.97-104
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    • 2009
  • In this paper we propose a Differentiated Services Based Admission Control and Routing Algorithm for IPv6 (ACMRA). The basic DiffServ architecture lacks an admission control mechanism, the injection of more QoS sensitive traffic into the network can cause congestion at the core of the network. Our Differentiated Services Based Admission Control and Routing Algorithm for IPv6 combines the admission control phase with the route finding phase, and our routing protocol has been designed in a way to work alongside DiffServ based networks. The Differentiated Services Based Admission Control and Routing Algorithm for IPv6 constructs label switched paths in order to provide rigorous QoS provisioning. We have conducted extensive simulations to validate the effectiveness and efficiency of our proposed admission control and routing algorithm. Simulation Results show that the Differentiated Services Based Admission Control and Routing Algorithm for IPv6 provides an excellent packet delivery ratio, reduces the control packets' overhead, and makes use of the resources present on multiple paths to the destination network, while almost each admitted flow shows compliance with its Service Level Agreement.