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Yayın Evaluation of the efficiency of mainline and ramp metering in highway traffic management(Işık Üniversitesi, 2020-06-16) Yaran, Güzem; Kesten, Ali Sercan; Işık Üniversitesi, Fen Bilimleri Enstitüsü, İnşaat Mühendisliği Yüksek Lisans ProgramıIn the study, the effects of the mainline and ramp control theories on the highway traffic flow are investigate. In order to eliminate to alleviate the traffic congestion problem, which has become a problem in high-population cities, the mainline and ramp controls are considered as a solution, and control networks are emphasized. Examples of applications and results in the world are given. The applicability of the methods to be used by examining the previous studies was first examined on a general model and then on a selected highway network. In the models prepared, vehicle speeds, travel times, flow (volume) concepts, and relationships between them are mentioned. In addition, general information about highway management was also provided before. Control models were examined with the Microscopic Simulation Program, the purpose and types of models applied were compared. The traffic simulation model of the region between K-8 and K-11 on the O-2 highway from Asia to Europe has been created and the effects created by the control have been examined by applying both ramp and mainline metering. Analysis results; It has been observed that the control of ramp and mainline scenarios provides benefits compared to uncontrolled situations. Among the benefits provided; when the analysis of the basic model and mainline metering is applied, it is seen that there is an increase of 20.76% in travel times and an increase of 19.78% in vehicle speeds. Nevertheless, the implications of these control scenarios should be thoroughly investigated. Simulation results show that Ramp Metering (RM) and Mainline Metering (MM) controls can be an effective method in the management of highway-highway connections. In this regard, it is recommended that the control strategies mentioned in intensive highway-to-highway participations be tested in real life in order to increase efficiency.Yayın Evaluation of acceleration characteristics on operational eco - driving(Işık Üniversitesi, 2020-06-16) Yıldıran, Çağlar Latif; Kesten, Ali Sercan; Işık Üniversitesi, Fen Bilimleri Enstitüsü, İnşaat Mühendisliği Yüksek Lisans ProgramıGreenhouse gasses is a main thread for global warming and there are several strategies that reducing GHG gasses especially in developing countries as using alternative fuel types, dealing with the congestion, maintaining the steady traffic flow, dealing with the maintenances of vehicle, managing desired speed and the acceleration rates and so on. Eco-Driving is indicating any implementations which enables driving more economic and ecologic style. One of the main concepts of eco-driving is configuring driving behaviour to reduce consumption and emissions. In this thesis, impact of driver's behaviour tried to be investigated by using an instantaneous emission modelling to obtain minimum acceleration deceleration rate in generically created urban network.Yayın Impact of traffic incident duration and road characteristics on traffic flow performance(Işık Üniversitesi, 2020-06-16) Alan, Ali Rıza; Kesten, Ali Sercan; Işık Üniversitesi, Fen Bilimleri Enstitüsü, İnşaat Mühendisliği Yüksek Lisans ProgramıNon-recurrent events that occur in any part of the highway such as accident, vehicle breakdown,fire, scattering of substances like load, fuel oil etc. on the road which disrupt the traffic flow are defined as traffic incidents. Traffic Incident Management is the planned and coordinated utilization of all human and institutional resources in order to reduce the negative effects of these incidents and to ensure the safety of the drivers, pedestrians, all other victims and response teams. Incidents generally causes congestion and yields in increased travel time which imposes costs to road users, either economic loss or reduced quality of life and mobility. This thesis presents the recent literature review on the traffic incident management theory and practice along with the traffic incident simulation models. The thesis study is comprised of two parts; a data collection and analysis and a simulation experiment phase. Firstly, Traffic incident data from Istanbul Metropolitan Area is collected and analyzed. Secondly, a microscopic traffic simulation model was developed to simulate different types of incidents and traffic demand and also various geometric characteristics of highway. The analyses are performed taking total travel time, queue length and the speed as performance measures. Lastly, to evaluate and compare the performance of the cases, statistical tests are applied. The results show that there is a linear relationship between the incident duration and the average flow speed. The increase in incident duration causes the decrease in average speed up to 11.8% for overall traffic flow and up to 29.6% for the traffic flow of the post-incident process. The longest average queue length is observed in incidents in the middle lane. The shortest average queue length is observed in incidents in the right lane. In incidents in the middle lane, queue length increases up to 34.6% compared to the incidents in the right lane for overall traffic flow. In cases where the number of vehicles per lane is the same, the increase in the number of lanes causes a decrease in average speed up to 6.4% for the traffic flow of the post-incident process. According to the results of the applied statistical tests, when overall simulation periods are analyzed, statistically different results are seen only in incident duration, vehicle input, and lane width changes. When post-incident processes are analyzed, statistically different results are seen only in incident duration and lane width changes. The results of this thesis could be used by the traffic control authorities to reduce incident duration, congestion, secondary incidents, and the associated human and economic losses.Yayın Constraint-based routing in traffic engineering(IEEE, 2006) Karaman, AyşeTraffic engineering (TE) describes a domain-wide perspective for traffic control as opposed to application-specific concerns of QoS. MPLS is today's most powerful architecture for TE. Constraint-based routing refers to the process of path assignment to flows to fulfill the TE objective which has been defined in a number of multi-constraint ways, and is the most significant component of TE. In this paper, we review constraint-based routing algorithms. We first provide an overview of MPLS/TE and place constraint-based routing within this approach. We then look into the potential path attributes and the underlying platform to characterize these algorithms before we present our review. Our study provides a comprehensive reference to the operational structure and specifications of constraint-based routing algorithms.
