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NIMA DADASHZADEH received the B.S. and M.S. degrees in civil engineering from the Azad University, Zanjan, Iran, in 2010 and 2013, respectively, and a Ph.D. degree in transportation engineering from Technical University of Istanbul, Turkey, in 2019. In 2017, he joined the traffic Technical Institute (TTI) of the University of Ljubljana, Slovenia. Between 2018 and 2019, he was working as a researcher in two EU Interreg funded projects, namely, MUSE and EN-IN. He is currently working as a postdoctorate researcher and teaching assistant at TTI. His research interests include traffic simulation, transport planning and modeling, bus priority methods, and shared mobility modes. He is an active reviewer of several journals such as: IEEE Access, Public Transport (Springer), European Transport Research Review (Springer), Transportation Letters (Taylor and Francis Group), Journal of Advance Transportation, and MDPI journals (Sustainability, Logistics). Dr. Dadashzadeh is currently a scientific committee member of IEEE MT-ITS2021 “7th International conference on models and technologies for Intelligent Transportation Systems,” which will be held at Crete, Greece in 2021. Since 2019, he is acting as Management Committee (MC) Member from Slovenia, in EU COST Action CA16222: Wider Impacts and Scenario Evaluation of Autonomous and Connected Transport.
Existing public transport (PT) planning methods use a trip-based approach, rather than a user-based approach, leading to neglecting equity. In other words, the impacts of regular users—i.e., users with higher trip rates—are overrepresented during analysis and modelling because of higher trip rates. In contrast to the existing studies, this study aims to show the actual demand characteristic and users’ share are different in daily and monthly data. For this, 1-month of smart card data from the Kocaeli, Turkey, was evaluated by means of specific variables, such as boarding frequency, cardholder types, and the number of users, as well as a breakdown of the number of days traveled by each user set. Results show that the proportion of regular PT users to total users in 1 workday, is higher than the monthly proportion of regular PT users to total users. Accordingly, users who have 16–21 days boarding frequency are 16% of the total users, and yet they have been overrepresented by 39% in the 1-day analysis. Moreover, users who have 1–6 days boarding frequency, have a share of 66% in the 1-month dataset and are underrepresented with a share of 22% in the 1-day analysis. Results indicated that the daily travel data without information related to the day-to-day frequency of trips and PT use caused incorrect estimation of real PT demand. Moreover, user-based analyzing approach over a month prepares the more realistic basis for transportation planning, design, and prioritization of transport investments.
Kiarash Ghasemlou; Murat Ergun; Nima Dadashzadeh. Exploring Equity in Public Transportation Planning Using Smart Card Data. Sensors 2021, 21, 3039 .
AMA StyleKiarash Ghasemlou, Murat Ergun, Nima Dadashzadeh. Exploring Equity in Public Transportation Planning Using Smart Card Data. Sensors. 2021; 21 (9):3039.
Chicago/Turabian StyleKiarash Ghasemlou; Murat Ergun; Nima Dadashzadeh. 2021. "Exploring Equity in Public Transportation Planning Using Smart Card Data." Sensors 21, no. 9: 3039.
The introduction of shared autonomous vehicles into the transport system is suggested to bring significant impacts on traffic conditions, road safety and emissions, as well as overall reshaping travel behaviour. Compared with a private autonomous vehicle, a shared automated vehicle (SAV) is associated with different willingness-to-adopt and willingness-to-pay characteristics. An important aspect of future SAV adoption is the presence of other passengers in the SAV—often people unknown to the cotravellers. This study presents a cross-country exploration of user preferences and WTP calculations regarding mode choice between a private non-autonomous vehicle, and private and shared autonomous vehicles. To explore user preferences, the study launched a survey in seven European countries, including a stated-preference experiment of user choices. To model and quantify the effect of travel mode attributes and socio-demographic characteristics, the study employs a mixed logit model. The model results were the basis for calculating willingness-to-pay values for all countries and travel modes, and provide insight into the significant heterogeneous, gender-wise effect of cotravellers in the choice to use an SAV. The study results highlight the importance of analysis of the effect of SAV attributes and shared-ride conditions on the future acceptance and adoption rates of such services.
Amalia Polydoropoulou; Ioannis Tsouros; Nikolas Thomopoulos; Cristina Pronello; Arnór Elvarsson; Haraldur Sigþórsson; Nima Dadashzadeh; Kristina Stojmenova; Jaka Sodnik; Stelios Neophytou; Domokos Esztergár-Kiss; Jamil Hamadneh; Graham Parkhurst; Shelly Etzioni; Yoram Shiftan; Floridea Di Ciommo. Who Is Willing to Share Their AV? Insights about Gender Differences among Seven Countries. Sustainability 2021, 13, 4769 .
AMA StyleAmalia Polydoropoulou, Ioannis Tsouros, Nikolas Thomopoulos, Cristina Pronello, Arnór Elvarsson, Haraldur Sigþórsson, Nima Dadashzadeh, Kristina Stojmenova, Jaka Sodnik, Stelios Neophytou, Domokos Esztergár-Kiss, Jamil Hamadneh, Graham Parkhurst, Shelly Etzioni, Yoram Shiftan, Floridea Di Ciommo. Who Is Willing to Share Their AV? Insights about Gender Differences among Seven Countries. Sustainability. 2021; 13 (9):4769.
Chicago/Turabian StyleAmalia Polydoropoulou; Ioannis Tsouros; Nikolas Thomopoulos; Cristina Pronello; Arnór Elvarsson; Haraldur Sigþórsson; Nima Dadashzadeh; Kristina Stojmenova; Jaka Sodnik; Stelios Neophytou; Domokos Esztergár-Kiss; Jamil Hamadneh; Graham Parkhurst; Shelly Etzioni; Yoram Shiftan; Floridea Di Ciommo. 2021. "Who Is Willing to Share Their AV? Insights about Gender Differences among Seven Countries." Sustainability 13, no. 9: 4769.
Dispersed settlement areas (e.g., Slovenia) result in lower development of fixed public transport lines and thereby car-dependent lifestyles. To avoid congestion inside the cities and on highways in these areas, shared mobility modes e.g., carpooling, is one of the effective solutions, increasing the occupancy of personal vehicles. However, passenger pick-up and drop-off locations still remain an important challenge for carpool users and transport officials. As a collection point for carpooling, we can consider “park and pool (P+P)” lots near highways’ interchanges. This study aims to examine the impacts of P+P lots near interchanges on carpooling behavior of users and on improving sustainable mobility on highways in such dispersed settlement areas. To do so, we employed a field survey, incorporated the P+P lots into the mode choice model, and examined different scenarios using the macroscopic transport model. It is found that factors such as travel cost, public transport service limitations, and improved parking facilities impact highway users’ mode choice. Sixty percent of respondents are willing to leave their car in P+P lots near interchanges. The results also show that P+P lots can increase the number of carpool users. It causes remarkable savings in terms of operating and external costs because of the reduction in total distance and time travelled by personal vehicles as well as parking demand reduction in cities. At the moment, especially in Central Europe, it is easier to invest in a “demand reduction” infrastructure than to increase the capacity of infrastructure. Therefore, P+P lots could be a “win-win” situation for both users and operators.
Robert Rijavec; Nima Dadashzadeh; Marijan Žura; Rok Marsetič. Park and Pool Lots’ Impact on Promoting Shared Mobility and Carpooling on Highways: The Case of Slovenia. Sustainability 2020, 12, 3188 .
AMA StyleRobert Rijavec, Nima Dadashzadeh, Marijan Žura, Rok Marsetič. Park and Pool Lots’ Impact on Promoting Shared Mobility and Carpooling on Highways: The Case of Slovenia. Sustainability. 2020; 12 (8):3188.
Chicago/Turabian StyleRobert Rijavec; Nima Dadashzadeh; Marijan Žura; Rok Marsetič. 2020. "Park and Pool Lots’ Impact on Promoting Shared Mobility and Carpooling on Highways: The Case of Slovenia." Sustainability 12, no. 8: 3188.
Under many circumstances, when providing full bus priority methods, urban transport officials have to operate buses in mixed traffic based on their road network limitations. In the case of Istanbul's Metrobus lane, for instance, when the route comes to the pre-designed Bosphorus Bridge, it has no choice but to merge with highway mixed traffic until it gets to the other side. Much has been written on the relative success of implementing Ramp Metering (RM), for example ALINEA (‘Asservissement line´ aire d’entre´ e autoroutie’) and Variable Speed Limits (VSL), two of the most widely-used “merging congestion” management strategies, in both a separate and combined manner. However, there has been no detailed study regarding the combination of these systems in the face of high bus volume. This being the case, the ultimate goal of this study is to bridge this gap by developing and proposing a combination of VSL and RM strategies in the presence of high bus volume (VSL+ALINEA/B). The proposed model has been coded using microscopic simulation software—VISSIM—and its vehicle actuated programming (VAP) feature; referred to as VisVAP. For current traffic conditions, the proposed model is able to improve total travel time by 9.0%, lower the number of average delays of mixed traffic and buses by 29.1% and 81.5% respectively, increase average speed by 12.7%, boost bottleneck throughout by 2.8%, and lower fuel consumption, Carbon Monoxide (CO), Nitrogen Oxides (NOx), and Volatile Organic Compounds (VOC) emissions by 17.3% compared to the existing “VSL+ALINEA” model. The results of the scenario analysis confirmed that the proposed model is not only able to decrease delay times on the Metrobus system but is also able to improve the adverse effects of high bus volume when subject to adjacent mixed traffic flow along highway sections.
Nima Dadashzadeh; Murat Ergun. An Integrated Variable Speed Limit and ALINEA Ramp Metering Model in the Presence of High Bus Volume. Sustainability 2019, 11, 6326 .
AMA StyleNima Dadashzadeh, Murat Ergun. An Integrated Variable Speed Limit and ALINEA Ramp Metering Model in the Presence of High Bus Volume. Sustainability. 2019; 11 (22):6326.
Chicago/Turabian StyleNima Dadashzadeh; Murat Ergun. 2019. "An Integrated Variable Speed Limit and ALINEA Ramp Metering Model in the Presence of High Bus Volume." Sustainability 11, no. 22: 6326.
Most of the microscopic traffic simulation programs used today incorporate car-following and lane-change models to simulate driving behaviour across a given area. The main goal of this study has been to develop an automatic calibration process for the parameters of driving behaviour models using metaheuristic algorithms. Genetic Algorithm (GA), Particle Swarm Optimization (PSO), and a combination of GA and PSO (i.e. hybrid GAPSO and hybrid PSOGA) were used during the optimization stage. In order to verify our proposed methodology, a suitable study area with high bus volume on-ramp from the O-1 Highway in Istanbul has been modelled in VISSIM. Traffic data have been gathered through detectors. The calibration procedure has been coded using MATLAB and implemented via the VISSIM-MATLAB COM interface. Using the proposed methodology, the results of the calibrated model showed that hybrid GAPSO and hybrid PSOGA techniques outperformed the GA-only and PSO-only techniques during the calibration process. Thus, both are recommended for use in the calibration of microsimulation traffic models, rather than GA-only and PSO-only techniques.
Nima Dadashzadeh; Murat Ergun; Sercan Kesten; Marijan Žura. An Automatic Calibration Procedure of Driving Behaviour Parameters in the Presence of High Bus Volume. Promet - Traffic&Transportation 2019, 31, 491 -502.
AMA StyleNima Dadashzadeh, Murat Ergun, Sercan Kesten, Marijan Žura. An Automatic Calibration Procedure of Driving Behaviour Parameters in the Presence of High Bus Volume. Promet - Traffic&Transportation. 2019; 31 (5):491-502.
Chicago/Turabian StyleNima Dadashzadeh; Murat Ergun; Sercan Kesten; Marijan Žura. 2019. "An Automatic Calibration Procedure of Driving Behaviour Parameters in the Presence of High Bus Volume." Promet - Traffic&Transportation 31, no. 5: 491-502.
The calibration procedure for traffic simulation models can be a very time-consuming process in the case of a large-scale and complex network. In the application of Evolutionary Algorithms (EA) such as Genetic Algorithms (GA) and Particle Swarm Optimization (PSO) for calibration of traffic simulation models, objective function evaluation is the most time-consuming step in such calibration problems, because EA has to run a traffic simulation and calculate its corresponding objective function value once for each set of parameters. The main contribution of this study has been to develop a quick calibration procedure for the parameters of driving behavior models using EA and parallel computing techniques (PCTs). The proposed method was coded and implemented in a microscopic traffic simulation software. Two scenarios with/without PCT were analyzed using the developed methodology. The results of scenario analysis show that using an integrated calibration and PCT can reduce the total computational time of the optimization process significantly - in our experiments by 50% - and improve the optimization algorithm’s performance in a complex optimization problem. The proposed method is useful for overcoming the limitation of computational time of the existing calibration methods and can be applied to various EAs and traffic simulation software.
Nima Dadashzadeh; Murat Ergun; Ali Sercan Kesten; Marijan Zura. Improving the calibration time of traffic simulation models using parallel computing technique. 2019 6th International Conference on Models and Technologies for Intelligent Transportation Systems (MT-ITS) 2019, 1 -7.
AMA StyleNima Dadashzadeh, Murat Ergun, Ali Sercan Kesten, Marijan Zura. Improving the calibration time of traffic simulation models using parallel computing technique. 2019 6th International Conference on Models and Technologies for Intelligent Transportation Systems (MT-ITS). 2019; ():1-7.
Chicago/Turabian StyleNima Dadashzadeh; Murat Ergun; Ali Sercan Kesten; Marijan Zura. 2019. "Improving the calibration time of traffic simulation models using parallel computing technique." 2019 6th International Conference on Models and Technologies for Intelligent Transportation Systems (MT-ITS) , no. : 1-7.
Urban transit systems consist of multiple modes of transport of which cars and buses make up the largest portion, particularly in developing countries. Thus, theories on the best means of allocating existing road spaces for cars and buses in city-centers and suburban corridors in order to improve operational transport efficiency has become a frontier research topic. Today, bus priority (BP) methods, as one of the most widely used Public Transport Priority (PTP) strategies, are commonly recognized as effective in lowering traffic congestion and reducing bus travel times. PT authorities, urban planners/designers, and researchers dealing with PT issues (i.e. buses), need to investigate existing BP methods in detail and assess relevant research before setting about designing or implementing new policies. Of course, evaluating such studies is a time-consuming process. In order to address this constraint, the present study proposes a general typology of existing BP methods and evaluates the challenges and requirements regarding their implementation by conducting a comprehensive literature review of existing studies related to PTP. Academic papers (theoretical, analytical, and simulation-based), technical reports, and design manual/guidelines in the context of both developed and developing countries have been searched as part of the literature review process. The study concludes by proposing two comparative summary tables of all spatial bus priority schemes in terms of “min. requirements to justify BP schemes” and “advantages and disadvantages of time-based and spatial BP treatments”. These may provide engineers, urban planners or transit policy-makers with an accessible guide with which to refer in the evaluation stage. However, future research is recommended in order to bridge existing gaps concerning conditions required for the successful implementation of spatial bus priority strategies.
Nima Dadashzadeh; Murat Ergun. Spatial bus priority schemes, implementation challenges and needs: an overview and directions for future studies. Public Transport 2018, 10, 545 -570.
AMA StyleNima Dadashzadeh, Murat Ergun. Spatial bus priority schemes, implementation challenges and needs: an overview and directions for future studies. Public Transport. 2018; 10 (3):545-570.
Chicago/Turabian StyleNima Dadashzadeh; Murat Ergun. 2018. "Spatial bus priority schemes, implementation challenges and needs: an overview and directions for future studies." Public Transport 10, no. 3: 545-570.