31 research outputs found

    Calibrating Car-Following Models using Trajectory Data: Methodological Study

    Full text link
    The car-following behavior of individual drivers in real city traffic is studied on the basis of (publicly available) trajectory datasets recorded by a vehicle equipped with an radar sensor. By means of a nonlinear optimization procedure based on a genetic algorithm, we calibrate the Intelligent Driver Model and the Velocity Difference Model by minimizing the deviations between the observed driving dynamics and the simulated trajectory when following the same leading vehicle. The reliability and robustness of the nonlinear fits are assessed by applying different optimization criteria, i.e., different measures for the deviations between two trajectories. The obtained errors are in the range between~11% and~29% which is consistent with typical error ranges obtained in previous studies. In addition, we found that the calibrated parameter values of the Velocity Difference Model strongly depend on the optimization criterion, while the Intelligent Driver Model is more robust in this respect. By applying an explicit delay to the model input, we investigated the influence of a reaction time. Remarkably, we found a negligible influence of the reaction time indicating that drivers compensate for their reaction time by anticipation. Furthermore, the parameter sets calibrated to a certain trajectory are applied to the other trajectories allowing for model validation. The results indicate that ``intra-driver variability'' rather than ``inter-driver variability'' accounts for a large part of the calibration errors. The results are used to suggest some criteria towards a benchmarking of car-following models

    Bim and genetic algorithm optimisation for sustainable building envelope design

    Get PDF
    Decision-making (DM) at the early building design stages is essential to optimise sustainability performances. Nevertheless, the current methods of optimising building sustainability are complex as they involve multiple design variables and performance objectives. With the development of building information modelling (BIM), complicated buildings can be digitally constructed with precise geometry and accurate information for design optimisation in the early stages of project. Thus, this study explores the use of BIM and Genetic Algorithm (GA) to support DM and optimisation for sustainable building envelope design. To develop a BIM-GA optimisation method, Autodesk Revit template was created to extract data of building envelope from a Base Model (BM). Then, the data were employed to compute overall thermal transfer value (OTTV) and construction cost for BM evaluation and GA optimisation. A hypothetical building was modelled and then analysed using the proposed method as a test case. The BIM-GA optimisation method can address the difficulties of DM on building sustainability in the early design process

    A comparative stratigraphy of cilicia : Results of the first three cilician chronology workshops

    Get PDF
    This article presents a preliminary comparative stratigraphy of excavated sites in Plain Cilicia and one in Rough Cilicia. It is the outcome of three workshops held in 2014, 2015 and 2017. Plain Cilicia at the junction of Anatolia, Syro-Mesopotamia and Cyprus is one of the most fertile regions of the Ancient Near East. In recent years, archaeological research in the region has intensified, re-opening questions of chronology. The comparative stratigraphy discussed in the workshops is presented here in form of a gazetteer of the participating sites and a chart. This is to be understood as a first step towards a more comprehensive chronology

    Zur Modularisierung und Interpretierbarkeit Neuronaler Netze

    No full text
    SIGLETIB: DU 1249 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

    Importance of a view window in rating green office buildings

    No full text
    The essence of a view window (VW) in an office building is not only to bring an optimal balance between daylight and electric light, but also for psychological and health purpose. VW does not only allow the admittance of light and views, but indirectly affects the productivity and psychological wellbeing of office occupants; it has a link to the sustainability in both conventional and green buildings. This paper defines the function of a view window as it relates to green office building. Through literature review and an experiment conducted in room 432-01 located at B11 Faculty of Built Environment, Universiti Teknologi Malaysia. The function of VW in a green office building is highlighted; and the findings show that a VW would enhance sustainability in an office setting and has a dimension greater than 750mm above a finish floor level and less or equal to 2300mm above a finish floor level and with a wall to window ratio (WWR) of 25% to 40%
    corecore