• TRAFFIC SYNTHETIC MODEL DEVELOPMENT AND CALIBRATION IN ANAMORAVA REGION

    Machines. Technologies. Materials., Vol. 13 (2019), Issue 4, pg(s) 173-177

    The main objective of this paper is to develop and calibrate traffic synthetic model for forecasting traffic demand in Anamorava region. The model on existing situation is developed based on “meta model” which uses PTV Visum software. In order to set up a model were taken into account input variables number of residents, number of people employed, working places available as well as the traffic volume entering and exiting this region at “peak hour”. With intention to have traffic volumes as an outcome expressed as AADT, correction coefficients are applied. Multiplying the traffic volumes with correction coefficient there is traffic demand gained for the period of 24 hours which is an indicator to be used for comparison of results. In order to get the reliable model for forecasting, calibration of it is done through TFlow Fuzzy algorithm technique based on GEH test, R2 and percentage deviation criterions. Once the level is completed satisfactory, the final model can be used to forecast the traffic demand for this region.

  • TECHNOLOGIES

    THE DEVELOPMENT OF CALIBRATION FOR THE ROLLING BALLS OF DIAMETER 40 MM IN CONDITIONS OF JSC "SSGPO"

    Machines. Technologies. Materials., Vol. 12 (2018), Issue 1, pg(s) 16-18

    Paper presents a preliminary calculation of the calibration rolls for rolling balls with a diameter of 40 mm in a rolling mill JSC "SSGPO", which will be rolled from round workpieces with a diameter of 40 mm. The main elements of ball caliber are considered, their design dimensions are determined. It is established that the height of the flange varies linearly and the width of the spherical area increases during rolling.

  • MATHEMATICAL MODELLING OF TECHNOLOGICAL PROCESSES AND SYSTEMS

    VEHICULAR TRAFFIC FLOW MODELLING BY MEANS OF CAR-FOLLOWING APPROACH

    Mathematical Modeling, Vol. 1 (2017), Issue 1, pg(s) 57-60

    This paper concerns the problem of vehicular traffic flows simulation. We present a continuous car-following model with explicit reaction-time delay. This model is based on the Intelligent Driver Models and eliminates some drawbacks like unrealistic distance between vehicles in a homogeneous flow and instant reaction of a driver. The model is defined by a couple of delayed differential equations. Introducing reaction time explicitly one can simulate traffic flow instabilities such as kinematic waves with a greater degree of realism. We calculate conditions for that the linear stability occurs on a ring and in the finite platoon of cars. The parameters of the model are calibrated according to NGSIM trajectory data. Another method described in this paper allows to estimate parameters according to technical characteristics of the specific vehicle type. Simulating vehicular traffic for large cities with microscopic approach one needs to solve tremendous systems of differential equations. The speed of changes in the size of the components of such systems usually lies in a wide range, as the dynamics and behaviour of the vehicles can strongly differ. We introduce a multirate numerical scheme with a self-adjusting time stepping strategy. The step size for each component is determined by its own local temporal variation. The stability analysis for the developed scheme is performed and the stability conditions are obtained. The use of multiple time steps allows parallel computing.