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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 Analyzing the benefits and challenges of the building information modelling and life cycle assessment integration(Işık Üniversitesi, 2019-07-17) Azizoğlu, Heval Botan; Seyis, Senem; Işık Üniversitesi, Fen Bilimleri Enstitüsü, İnşaat Mühendisliği Yüksek Lisans ProgramıThe architecture, engineering and construction (AEC) industry involves the large quantities of material and energy consumption. Previous studies show that the AEC industry consumes about 40 percent of primary energy utilization and contributes up to more than half of global GHG emissions. With the aim of decreasing these negative impacts of AEC industry on the natural environment, the integrated use of advanced technological instruments has been increasing in the last decade. One of the promising technological instrument integrations is the collaborative use Building Information Modeling (BIM) and Life Cycle Assessment (LCA) which is able to decrease negative impacts of AEC industry on natural environment in an e ective and e cient manner. The objective of this MS thesis is to identify, classify and prioritize the bene ts and challenges of the integrated use of Building Information Modelling and Life Cycle Assessment in the AEC industry. In order to achieve research objectives of this thesis, a comprehensive literature review, semi-structured interviews with experts and Delphi method were performed. The interrater agreement and signi cance-level statistics were conducted for analyzing and validating the consensus among the Delphi method participants. Results of this study provide twenty-two types of bene ts and seven types of challenges for the integrated use of BIM and LCA in the AEC industry. The contributions of this thesis are a comprehensive identi cation, classi cation and prioritization of the integrated use of BIM and LCA. The results of this study may contribute to extend utilization of BIM-LCA integration in the AEC industry.Yayın Analytical and numerical analysis of the dissipative kundu-eckhaus equation(Işık Üniversitesi, 2019-12-02) Yurtbak, Hazal; Bayındır, Cihan; Işık Üniversitesi, Fen Bilimleri Enstitüsü, İnşaat Mühendisliği Yüksek Lisans ProgramıIt is well-known that the Kundu-Eckhaus equation (KEE) is a nonlinear equation which belongs to nonlinear Schrödinger class and it is commonly used as a model to investigate the dynamics of diverse phenomena in many areas including but are not limited to hydrodynamics, fiber and nonlinear optics, plasmas and finance. However, the effects of dissipation on the dynamics of KEE have not been investigated so far. In this thesis, in order to address this open problem we propose the dissipative Kundu-Eckhaus equation (dKEE) and perform an analytical and numerical analysis of the dKEE. With this motivation, we derive a simple monochromatic wave solution to dKEE. Then, we propose a split step Fourier method (SSFM) for the numerical solution of the dKEE and we test the stability of the SSFM using the analytical solution derived as a benchmark problem. Observing the stability and the accuracy of the scheme, we first investigate the rogue wave dynamics of the dKEE using the SSFM. More specifically, we show that modulation instability (MI) turns the monochromatic wave field into a chaotic one, thus the appearance of rogue waves become obvious. We discuss the properties and characteristics of such rogue waves. Additionally, we depict the amplitude probability distribution functions (PDFs) and discuss the effects of diffusion, Raman and dissipation coeficient as well as the MI parameters on the probability of rogue wave occurrence. Secondly, we investigate the effects of dissipation on the self-localized solitons of the KEE. For this purpose, we propose a Petviashvili method (PM) to obtain the self-localized solitons of the KEE and analyze the effects of dissipation by time stepping of these solitons using the SSFM proposed for dKEE. It is known that, KEE admits stable single, two and N-soliton solutions for the no potential case. It has been recently found that, under the effect of photorefractive and saturable potentials, such solitons of the KEE become unstable. We show that the dissipation parameter can be used to stabilize the single, two and three solitons of the KEE which do not satisfy the necessary Vakhitov-Kolokolov condition for the soliton stability. With this aim, we present the power graphs as functions of soliton eigenvalue and as well as time. Additionally, we depict the soliton shapes for various times to show that they are preserved for time scales long enough for many engineering purposes.We comment on our findings and discuss the applicability and uses of our results. Additionally, we suggest possible directions for the near future research activities.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.
