Yazar "Demir, Hatice G." seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    A comparison of traffic flow performance of roundabouts and signalized intersections: A case study in nigde
    (Bentham Science Publishers, 2020) Demir, Hatice G.; Demir, Yusuf K.
    Background: Intersections affect the safety and capacity of urban traffic. Therefore, the design and selection of the type of intersection need to be made very carefully. According to the demand level, a different intersection can be designed. Signalized intersections are one of the intersection types in which the sequence and duration of the flow at the intersection are provided by the lights. Generally, this type of intersection is used on roads with high traffic volume. Modern roundabouts are one of the types of circular intersections that provide advantages over other types of intersection in terms of smooth operation and safety. Modern roundabouts exist in several types today worldwide. In practice, the distinction about the kinds of roundabouts would not be fully clarified; as a result, queuing and delay can be seen as negative effects. Methods: In this study, to make a distinction and clarify the kinds of roundabouts, first, the roundabouts types are introduced according to geometric and operational aspects. A signalized intersection, where a circular island is placed and also signalized, was investigated in terms of capacity, delay, and emissions located in Niğde. The traffic flow performance of the current state (nested signalized roundabout) was calculated with HCM Method (for signalized intersection) using SIDRA and compared with roundabout solutions of the intersection with HCM6 (for roundabout) method using SIDRA Intersection analysis software. Results: From the results of the intersection capacity analysis study based on HCM6, it was seen that the application of a roundabout scenario (intersection considered as a modern roundabout) showed higher performance at the intersections than the intersection having a secondary signal. Capacity increased to 67.8%, the average delay decreased to 72.8% and 95th percentile queue dropped to 82.2%. Conclusion: Roundabout controlling instead of a nested signal system can be an example of the increase in the performance of traffic flow. This highlights the importance of choosing the appropriate roundabout design. © 2020 Hatice Göçmen Demir and Yusuf Kağan Demir.
  • Küçük Resim Yok
    Öğe
    MODELLING AND CALIBRATION OF MICROSCOPIC SIMULATION MODEL CORSIM
    (City Net Scien Res Ctr Ltd-Belgrade, 2018) Demir, Yusuf Kagan; Demir, Hatice G.
    A simulation method is an effective tool in analyzing the various dynamic problems in recent years. Today, many studies related to Traffic Engineering and Transportation benefit from a simulation method. A simulation model reflects the real system through the instrument of mathematical models of operation relations in the system over determined time. Models are developed in order to evaluate the different design and control scenarios. Traffic flow simulation models are divided into three classes according to the detail level of simulation. These are microscopic, mesoscopic and macroscopic. CORSIM (CORridor SIMulation) has been developed by FHWA (U.S. Federal Road Administration), is one of the tops most used simulation software for transport professionals. The performance of the software has been tested and is used continuously by FHWA in many studies. CORSIM can integrate urban road and highway networks to each other, thus it is possible to test the interaction of the two types of network. CORSIM also offers to intervene to networks thanks to built-in control devices. As an example, Istanbul European side of the Bosporus Bridge near Freeway 01, 2.5 km part, was modeled and calibrated with CORSIM. Traffic Software Integrated System 6.1 software package was used. As a result of the calibration, the selected traffic behavior can be successfully represented by CORSIM according to the test criteria. The Erlang distribution seems to be particularly successful in modeling speed. For this reason, the Erlang distribution will be used in subsequent CORSIM simulations. With the help of calibrated CORSIM, the traffic control methods to be applied to the working segment and the reaction that the traffic will give can be predicted. Thus, it is possible to test the validity of the work in the laboratory environment before applying it.