• Title/Summary/Keyword: Congested traffic

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Classification of Characteristics in Two-Wheeler Accidents Using Clustering Techniques (클러스터링 기법을 이용한 이륜차 사고의 특징 분류)

  • Heo, Won-Jin;Kang, Jin-ho;Lee, So-hyun
    • Knowledge Management Research
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    • v.25 no.1
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    • pp.217-233
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    • 2024
  • The demand for two-wheelers has increased in recent years, driven by the growing delivery culture, which has also led to a rise in the number of two-wheelers. Although two-wheelers are economically efficient in congested traffic conditions, reckless driving and ambiguous traffic laws for two-wheelers have turned two-wheeler accidents into a significant social issue. Given the high fatality rate associated with two-wheelers, the severity and risk of two-wheeler accidents are considerable. It is, therefore, crucial to thoroughly understand the characteristics of two-wheeler accidents by analyzing their attributes. In this study, the characteristics of two-wheeled vehicle accidents were categorized using the K-prototypes algorithm, based on data from two-wheeled vehicle accidents. As a result, the accidents were divided into four clusters according to their characteristics. Each cluster showed distinct traits in terms of the roads where accidents occurred, the major laws violated, the types of accidents, and the times of accident occurrences. By tailoring enforcement methods and regulations to the specific characteristics of each type of accident, we can reduce the incidence of accidents involving two-wheelers in metropolitan areas, thereby enhancing road safety. Furthermore, by applying machine learning techniques to urban transportation and safety, this study adds to the body of related literature.

Preference Analysis for U-City Services (U-City 분야별 서비스에 대한 선호도 분석)

  • Kim, Jong-Ki;Nam, Soo-Tai
    • The Journal of Information Systems
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    • v.19 no.4
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    • pp.51-63
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    • 2010
  • U-City applies ubiquitous information technologies such as RFID, GPS, USN to various components of city functions and services. The concept of U-City was popularized especially in Korea and currently more than 40 projects have been carrying out all over country. U-City incorporates advanced information communication technologies into ubiquitous information services to provide better quality of life. The purpose of this study is to analyze preferences for the U-City services by surveying experts in U-City developing companies. This study employs Analytic Hierarchy Process which is very useful tool for performing multi-criteria decision making. Total of 28 responses were used in the analysis. The results indicated that the first 7 most preferred items were from transportation and safety area and environment and healthcare area and 4 out of 6 items in transportation and safety area were ranked among them. It implies that respondents consider countering anxiety caused by congested traffic, natural disasters, crimes, etc most important aspect that U-City should deal with. On the other hand, U-Port, U-Convention, U-Logistics, U-Public Administration and U-City Portal were listed as the least preferred services.

Application of Percentile Speed for Appraisal of Road Section with Recurring Congestion (상습 지체구간 선정을 위한 Percentile 속도의 활용)

  • Kim, Hyung Gon;Lee, Ki Young;Lee, Soong Bong;Chang, Myungsoon
    • International Journal of Highway Engineering
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    • v.16 no.5
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    • pp.165-171
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    • 2014
  • PURPOSES : The objective of this study is to find Percentile Speed($V_p$) for Appraisal of Road Section with Recurring Congestion. METHODS : Percentile Speed($V_p$) is determined by correlation analysis of CSI that proposed existing literature. and CSI(Consistency Service Index) is a index that subtract service fail frequency from 100 points, and service fail is defined as traffic situation is driving less than 80kph speed. In this study, We analyzed the highest correlation percentile speed associated with CSI. This speed is chosen as a delay decision speed. In order to verifying reliability, it performed a comparison with the previous method. RESULTS : As a result, 30 percentile speed($V_{30}$) was decided as index speed for judgement of recurring congestion section, and through comparison with existing methods, we demonstrated that 30 percentile speed can be useful for judgement of recurring congestion section. CONCLUSIONS : This method to Determine recurring congestion section using the percentile speed($V_{30}$) was proposed for the first time in this paper. This method can be applicated more quickly and easily than existing method for determining of recurring delay section.

A Representative-based Multicast Congestion Control for Real-time Multimedia Applications (실시간 멀티미디어 응용을 위한 대표자 기반의 멀티캐스트 혼잡 제어)

  • Song, Myung-Joon;Cha, Ho-Jung;Lee, Dong-Ho
    • Journal of KIISE:Information Networking
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    • v.27 no.1
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    • pp.58-67
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    • 2000
  • The paper presents a representative-based feedback mechanism and rate adaptation policy for congestion control in multicast traffic for multimedia applications. In multicast congestion control, feedback implosion occurs as many receivers send feedback to a sender. We propose to use representatives to avoid the feedback implosion. In our scheme, receivers feedback packet loss information periodically and a sender adapts the sending rate based on the information collected through a hierarchy of representatives. A representative is selected in each region and roles as a filter to decrease the number of feedbacks. The simulation results show that the proposed scheme solves the feedback implosion problem and well adapts in a congested situation.

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Virtual Arrival Mechanism for IEEE 802.15.4 beacon enabled networks (비콘을 사용하는 IEEE 802.15.4 네트워크를 위한 가상 도착 메커니즘)

  • Ha, Jae-Yeol;Lee, Jong-Wook;Kwon, Wook-Hyun;Kim, Jung-Joon;Kim, Yong-Ho;Shin, Young-Hee
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.4 no.2
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    • pp.45-51
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    • 2005
  • For power constrained applications, IEEE 802.15.4 networks may be operated in beacon enabled mode with inactive period. h this paper, we propose the Virtual Arrival Mechanism (VAM) to avoid the congestion at the beginning of each contention access period (CAP). Virtual Arrival Mechanism (VAM) is a kind of traffic shaping that spread the traffics congested at the beginning of CAP into the whole CAP. By using VAM, collisions and energy consumption can be reduced. Finally, we evaluate the performance enhancement of VAM using NS-2 simulator.

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A Frame Collision Reduction Method for Safety Message Broadcasting in IEEE1609.4/IEEE802.11p based VANETs

  • Wang, Lei;Jing, Weiping
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.3
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    • pp.1031-1046
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    • 2018
  • Vehicular ad hoc network (VANET) is a dedicated network to connect vehicles without any centralized administration or infrastructure. The wireless access in vehicular environments (WAVE) protocol leveraging IEEE 1609/802.11p is widely implemented for VANETs. However, in congested traffic situation, the performance of the WAVE system degrades significantly due to serious collision, especially for safety related broadcast services on the control channel (CCH) interval due to the inherent drawback of its collision avoidance mechanisms called carrier sense multiple access with collision avoidance (CSMA/CA). In this paper, we propose a method that can decrease the number of frame collisions in CCH with a few modifications to the IEEE 802.11p protocol. In the paper, vehicles still employ CSMA/CA to compete for the channel access opportunity. However, by taking advantage of periodicity of synchronization interval, a two-state switching scheme introducing two new inter frame space (IFS) is proposed to reduce the number of competing vehicles substantially and as a result, the collision probability is significantly decreased. The simulation results demonstrate the superiority of the proposed method in packet collision rate.

Load Aware Automatic Channel Switching for Software-Defined Enterprise WLANs

  • Han, Yunong;Yang, Kun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.11
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    • pp.5223-5242
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    • 2017
  • In the last decade, the 2.4 GHz band of IEEE 802.11 WLANs has become heavily congested due to the explosive increase in demand of Wi-Fi connectivity. With the current deployment of enterprise WLANs, channel switching mechanism continues to exhibit inefficiencies because it cannot adapt to real-time channel condition and the inability to support seamless channel switching. Software Defined Networking (SDN) as an emerging architecture is promising to introduce flexibility and programmability for wireless network management. Leveraging SDN to existing enterprise WLANs, channel switching method can be improved significantly. This paper presents a software-defined enterprise WLAN framework with a load aware automatic channel switching solution, which utilizes AP load and channel interference factor (CIF) to provide seamless channel switching. Two automatic channel switching algorithms named Single Switch (SS) and Double Switch (DS) are proposed to improve the overall user experience and the experience of users with highest traffic load respectively. Experiment results demonstrate that our solution can efficiently improve user experience in terms of jitter, transmission delay and network throughout when compared to the conventional channel switching mechanism.

Changes in air pollutant emissions from road vehicles due to autonomous driving technology: A conceptual modeling approach

  • Hwang, Ha;Song, Chang-Keun
    • Environmental Engineering Research
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    • v.25 no.3
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    • pp.366-373
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    • 2020
  • The autonomous vehicles (AVs) could make a positive or negative impact on reducing mobile emissions. This study investigated the changes of mobile emissions that could be caused by large-scale adoption of AVs. The factors of road capacity increase and speed limit increase impacts were simulated using a conceptual modeling approach that combines a hypothetical speed-emission function and a traffic demand model using a virtual transportation network. The simulation results show that road capacity increase impact is significant in decreasing mobile emissions until the market share of AVs is less than 80%. If the road capacity increases by 100%, the mobile emissions will decrease by about 30%. On the other hand, driving speed limit increase impact is significant in increasing mobile emissions, and the environmentally desirable speed limit was found at around 95 km/h. If the speed limit increases to 140 km/h, the mobile emissions will increase by about 25%. This is because some vehicles begin to bypass the congested routes at high speeds as speed limit increases. Based on the simulation results, it is clear that the vehicle platooning technology implemented at reasonable speed limit is one of the AV technologies that are encouraging from the environmental point of view.

A Study of Successful Factor on PSD Application Technique for Manual Operation Mode(ATS) (수동운전(ATS)구간에서 PSD 적용 기술의 성공적 요인 분석연구)

  • Son, Yeong-Jin;Park, Keun-Soo;Min, Kyung-Yun
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.755-770
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    • 2006
  • 1974. 8.15 SeoulMetro, beginning with the first electric railway established at six cities, so it is managing mass transportation of traffic. Especially, in case of seoul, It is managing that from one to eight lines, 286.9km, 265 stations have installed and now it is carrying about 5.5million of passengers everyday, and 2,000million passengers a year. So accident is increasing from the station every year. For this measure, SeoulMetro prepares safety fence for passengers crash but, as suicides or people who watch the accident took place, for at the bottom of passengers crash protection, PSD installing is needed. Even though, PSD is managing ATO section but, in controlling SeoulMetro, one to four lines sections are (ATS, ATC)section. Between as ATS, ATC section, ATO section, subway gate and PSD must have opened and crossed always at the time. And the interlock control corrosion protection gate, managing skills with installation, method, using in history, apply to 10rail cars one train sets, and maximum applying 224% sections of passengers congested that consideration is to be needed. So 2004, SeoulMetro improved technology and basic design of PSD at ATS section. Based on this, from 2005.4 to 2006.6, using subway 2lines per 12stations set the model installation(full type 11stations, half type 1station) After installing in case of success, it is going about to suggest that effective analysis and hereafter subject.

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A Study on the Improvement of Physical Distribution System in Inchon Port (인천항 물류시스템의 실태분석 및 개선방안에 관한 연구 -입항지원시스템을 중심으로-)

  • 황해성;곽규석
    • Journal of Korean Port Research
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    • v.12 no.2
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    • pp.233-242
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    • 1998
  • The Inchon port has been heavily congested due to the tidal restriction in passing the lock and the shortage of berths or warehouses. The current congestion is predicted to become worse by the induced traffics near the lock entrance after completion of North harbour expansion and of Kyung-In canal construction. It is also expected that the newly developed configuration of the Inchon port will result in increasing the rate of marine accidents around the lock entrance because of the over-utilization of the limited capacity of the junction from the North harbour and the Kyung-In canal. This study adopts a systematic approach in analysing the physical distribution system of the inner-lock area in order to figure out alternative routes which are designed to improve the port efficiency. Ship maneuvering simulation is also attempted to propose a new approaching route to the canal as an alternative path in order to avoid the traffic accidents caused by the extreme congestion. The result of the ship maneuvering simulation demonstrates that the alternative routes by way of Buk-Sudo, Janbong-Sudo, north of Si-Do and Sin-Do is recommended routes which can satisfy the safety requirements of approaching to the canal entrance.

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