Search results for " Simulation model"

Traffic simulation models calibration using speed–density relationship: An automated procedure based on genetic algorithm

2016

Calibration of traffic models.Calibration as optimization problem.Use of genetic algorithm. This paper presents the first results of a research which applied a genetic algorithm to calibrate a microscopic traffic simulation model based on speed-density relationships. A large set of traffic data collected from the A22 Freeway, Italy, was used and a comparison was performed between the field measurements and the simulation outputs obtained for a test freeway segment by using the Aimsun microscopic simulator.The calibration was formulated as an optimization problem to be solved based on a genetic algorithm; the objective function was defined in order to minimize the differences between the sim…

Estimation of Passenger Car Equivalents for single-lane roundabouts using a microsimulation-based procedure

2017

Calibration of microscopic traffic simulation models for single-lane roundabouts.Use of a meta-analytical estimation of critical and follow up headways.Use of a genetic algorithm-based procedure.Calculation of passenger car equivalents for single-lane roundabouts. Passenger car equivalents for heavy vehicles are required to carry out capacity calculations and perform operational analysis of any road entity (roadway segments or intersections). At single-lane roundabouts, the constraints to the vehicular trajectories imposed by the curvilinear geometric design and the driver's gap acceptance behaviour are expected to produce an impact of the heavy vehicles on the quality of traffic flow diffe…

The impact of thermophysical properties and hysteresis effects on the energy performance simulation of PCM wallboards: Experimental studies, modellin…

2020

Abstract This paper presents a combined experimental and numerical procedure, developed to test the thermophysical behaviour of a real scale PCM wallboard, aiming at providing reliable data for the validation of building energy performance simulation tools. Data obtained from two experimental tests, conducted on real building elements integrating PCM undergoing complete and incomplete phase change, are considered for assessing the impact of thermal properties and hysteresis. A comprehensive comparative numerical analysis, performed by means of an in-house developed simulation tool, called DETECt, is carried out to investigate the reliability of several modelling and simulation approaches av…

Building dynamic balanced scorecards to enhance strategy design and planning in public utilities. Key-findings from a project in a city water company

2006

Increasing complexity and uncertainty of both business internal and external variables determines a growing need for prompt and accurate information. On this concern, in the last decade, there has been an increasing effort to provide public utilities with tools aimed to support decision makers in planning and control, by taking into account not only operational but also strategic issues. Among them, for 1instance, customer satisfaction, internal business process efficiency, business image, and bargaining power against other counterparts (e.g. the municipal administration). Often, however, such an effort has been oriented to generate a large volume of data, only focused on financial indicato…

Sensitivity of Regional Water Supply Systems Models to the Level of Skeletonization – A Case Study from Apulia, Italy

2015

AbstractSimulation models supported by state-of-the-art software packages are nowadays available to explore operation rules of regional water supply systems or to select structural alternatives for improving long-term service performances.Given the, sometimes high, complexity of these systems, model calibration can become a lengthy procedure and many runs are necessary before obtaining convincing results. However, even after calibration, depending on system's complexity and the number of time steps investigated, a single run can take up to several minutes, even on state-of-the-art computers, so that simulation time can become a true bottleneck if such models are to be coupled with metaheuri…

Closure to Using Hydrus 2-D Simulation Model to evaluate Wetted Soil Volume in Subsurface Drip Irrigation Systems.

2008

COMPARISON BETWEEN VEHICLE SPEED PROFILES ACQUIRED BY DIFFERENTIAL GPS AND UAV

2014

Traffic microscopic simulation models are able to represent traffic conditions and their evolution over time. They take into account the geometrical aspects of transport infrastructures, driver behavior and, step by step, the vehicles’ movements on the road network. The most widespread applications of these models are referred to accident management, route guidance problems (possibility of evaluating control strategies in real time), adaptive control of traffic-light and ramp metering (management and control of the ramps and flow). To accomplish this goal observational data of vehicles’ kinematic characteristics have to be acquired. These elements are not always easily available. In scienti…

Biproportional Method for Analysing Interindustry Dynamics: the case of France

1990

Two elements are being presented in this paper: (1) A new and original method for analysing matrix dynamics, called the synthetical biproportional projector method (SBP), which can be used to project input–output tables and compare one with another. (2) Some results for France for the important period 1970–85. The paper starts with the observation that no systematic study of the change in the French productive structure as displayed In the input–output tables (tableaux entries-sorties in France) has ever been made. This is unfortunate, since a complete series of data is now available concerning a key period of the French economic evolution including the petroleum crisis, European integratio…

Are No-Till Herbicide-Free Systems Possible? A Simulation Study

2022

Conservation agriculture (CA) allows farmers to reduce costs and enhance soil health, buttends to increase either weed infestation and associated crop yield loss, and/or herbicide use.We aimed to investigate how much tillage contributes to reducing weed infestation and yieldloss, and which systems and weed species are the most affected if tillage is deleted. Wecollected farming practices on 395 arable cropping systems from Spain and France, andsimulated them over 30 years and with 10 weather repetitions, using FLORSYS. This processbased model (Colbach et al., 2021, Field Crops Res 261:108006) simulates daily multi-speciesweed floras and crop canopies from cropping systems and pedoclimate ov…

Simulation of granular organic fertilizer application by centrifugal spreader

2021

There is no specialized equipment designed to spread granular cylindrical organic fertilizer in the soil. There are also no rational recommendations available on how to spread this type of fertilizer. Mineral fertilizer spreaders are most often used for spreading granulated organic fertilizer. However, these fertilizers are significantly different from mineral fertilizers. Due to these differences, organic granular fertilizers often are spread unevenly, and the fertilizer does not reach the required working width. Furthermore, the rate of spreading is not accurate, and the fertilizer is often crushed too much. The objective of this research is to develop a simulation model for granular orga…