Irena Ištoka Otković

Calibration of microsimulation traffic model using neural network approach

This paper presents the results of research on the applicability of neural networks in the process of computer calibration of a microsimulation traffic model. VISSIM microsimulation model is used for calibration done at the example of roundabouts in an urban area. The calibration method is based on the prediction of a neural network for one traffic indicator, i.e. for the traveling time between measuring points. Besides the traveling time, the calibration process further/also involves a comparison between the modeled and measured queue parameters at the entrance to the intersection. The process of validation includes an analysis of traveling time and queue parameters on new sets of data gathered both at the modeled and at a new roundabout. A comparison of the traffic indicators measured in the field and those simulated with the calibrated and uncalibrated microsimulation traffic model provides an insight into the performance of the calibration procedure.

Comparison of different heliport solutions for the Clinical hospital center in Osijek

Complexity in takeoff and landing operations of helicopters require careful planning and designing of heliport infrastructure. The worlds biggest aviation organization, namely Federal Aviation Administration and International Civil Aviation Organization, published their standards and designing recommendations for heliport designers to implement that are analyzed and compared in this paper. In the Republic of Croatia, helicopters are designed according to the recommendations of National heliport regulations which are based on recommendations of International Civil Aviation Organization (Annex 14). The practical part of the paper deals with the implementation of national heliport standard recommendations in two variants of heliport designs for emergency medical service for the clinical hospital center in Osijek. As a potential location of the new heliport for emergency medical transportation a transit port is analyzed because it is close to the clinical hospital center in Osijek and is well connected with the existing road infrastructure, and it is also possible to make a direct access to the hospital complex from the north side. Two solutions were analyzed and compared upon the criteria of accessibility, security of operations and possibility for instrument flight conditions, size of heliport and necessary areas, costs of building and maintenance and helicopter noise. There is an intention that regional capital cities that have clinical hospital centers need to have infrastructure for emergency helicopter transportation near the hospital.

EXPERIMENTAL DESIGN APPLIED TO MODELING OF THE AIR-TIGHTNESS OF A BUILDING

The paper presents experimental designs that can be used in modeling of the air-tightness of buildings as second-order functions using response surfac

USING A MICROSIMULATION TRAFFIC MODEL TO COMPARE TWO-LANE AND TURBO-ROUNDABOUTS

Microsimulation traffic models are used to analyze and predict the functionality and safety of traffic networks, especially in critical areas such as

Analysis of neural network responses in calibration of microsimulation traffic model

Microsimulation models are frequently used in traffic analysis. Various optimization methods are used in calibration, and the one method that has shown success is neural networks. This paper shows the responses of neural networks during calibration of a microsimulation traffic model. We analyzed two calibration methods by applying neural networks and comparing their neural network learning (according to their achieved correlation and the mean error of prediction) and their generalization ability (comparison of generalization results was analyzed in two steps). The best correlation between the microsimulation results and neural network prediction was 88.3%, achieved for the traveling time prediction, on which the first calibration method is based.

ZAKONSKI OKVIRI I PLANIRANJE GOSPODARENJA CESTAMA

Zavrsetkom razdoblja intenzivne gradnje prometnica, dominantnim postaje gospodarenje prometnom infrastrukturom. Održavanje prometnica obavlja se su