Dusan Jolovic
New Mexico State University, Civil Engineering, Graduate Student
- I have graduated with BA from University of Belgrade in 2009. My undergraduate studies are closely related to the tra... moreI have graduated with BA from University of Belgrade in 2009. My undergraduate studies are closely related to the traffic and transportation engineering. In August 2010 I started my Master studies at Florida Atlantic University. I worked on the projects related to the traffic signal optimization, transportation safety evaluations, freeway assessments and traffic management centers.
After I graduated in May 2012, I was working as Engineering Assistant at Florida Atlantic University. My duties were to schedule meetings, write quarterly and draft reports, manage the transportation lab and work with undergraduate students.
Since 2013 I am working on my PhD degree at New Mexico State University. I have duties as Teaching and Research assistant. I am also the Secretary of Civil Engineering Graduate Student Association, where I am involved in community service and volunteering work for the city and the University.
Since 2014, I am married and I live with my wife in Las Cruces. We like to travel, go hiking to Organ mountains and go camping.edit - Peter T Martinedit
Arterial traffic signal systems, predominantly in the United States, deploy multiple signal timing plans to account for daily variability of traffic demand. Those types of traffic flow deviations should be anticipated when timing plans... more
Arterial traffic signal systems, predominantly in the United States, deploy multiple signal timing plans to account for daily variability of traffic demand. Those types of traffic flow deviations should be anticipated when timing plans are designed and, therefore, serviced satisfactorily. When traffic flow patterns are no longer predictable, a predetermined time-of-day (TOD) plan may no longer be the optimal one. This research aimed to examine signal timing optimality by applying a method similar to the selection of a traffic responsive plan to recognize automatically the best timing plan suited to current traffic conditions. The proposed method attempted to determine whether the optimality of signal timing settings could have been effectively estimated when systematic detector counts of the major approach were available. The study used 4 months of data from field microwave detectors coupled with data of turning-movement counts obtained over several days. The findings show that TOD signal timing plans mainly depended on adequate data collection that best describes a specific set of traffic conditions. Thus, the designed plan was as optimal as the related traffic information was reliable, whereas a problem arose in the case of limited-availability and low-quality data. New technologies are capable of collecting and storing massive amounts of data. Even if the granularity of collected data is low, the data can be used to improve traffic performance (i.e., reduce corridor delay). This realization could be of particular importance to traffic agencies that have installed, or plan to install, new field devices. Most urban traffic signal systems in the United States deploy multiple signal timing plans to account for within-day variability of traffic demand (i.e., morning peak, midday, evening peak, off peak, and nighttime). Signal groups forming a zone or section usually operate in a coordinated manner along an urban arterial. This coordination essentially means that signal timing plans change at the same time for all signals in a given group (zone, section etc.) to facilitate vehicle progression throughout a series of signals (1). Any type of unusual circumstances, such as incidents, construction, or severe weather, causes a significant change in anticipated traffic conditions. Traffic flow patterns are no longer predictable a priori, and a predetermined time-of-day (TOD) plan may substantially underperform under these conditions. In contrast, day-today and diurnal variations in traffic volumes and patterns are typically considered to be served in a satisfactory manner by the developed plans, because these deviations should be anticipated when the plans are originally designed. Traffic responsive plan selection (TRPS) and adaptive traffic control systems designed and deployed over the past several decades were intended to provide quicker response to constantly varying traffic conditions (2). A recent application included development of a real-time weather-responsive signal control (3). These advances attempted to incorporate more robustness into designed signal timing plans. Common existing engineering practice tends to rely on limited observations of relevant traffic patterns and volumes by considering a small data set only over several weekdays. Traffic signal settings (e.g., cycle length, splits, and offsets) are fixed within each TOD period, but traffic demands may still fluctuate significantly. Examining historical volume variations in daily traffic and corresponding responsiveness of the traffic control system can assist traffic engineers in assessing deficiencies in the state of the current traffic system. Well-designed signal control settings reduce delay and unnecessary stops at intersections and thus improve traffic flow without roadway widening. Hence, a key priority for transportation agencies is to ensure demand-suitable traffic signal timings. Yet, despite readily available detector counts, many do not regularly collect, review, or assess the quality of the traffic information they use when signal timings are designed and updated. This study attempts to demonstrate the benefit of using a large set of directional sensor data to estimate day-today variations in demand and proposing a straightforward method to evaluate current performance of TOD signal plans. The proposed approach estimates how the system would perform if it deployed an adaptive-TRPS signal control logic and whether the difference in performance warrants system retiming or upgrade. The practicality of this method is reflected in reducing the time and effort required by the existing signal design-retiming practice. Therefore, the purpose of this research is to devise a methodology to assess the extent to which existing timing plans along an arterial corridor are serving observed demands in a manner that is close to optimal and thereby to provide an upper bound on the potential
Research Interests:
The New Mexico Statewide Travel Demand Model (NMSTDM) has served a number of purposes since its initial development, providing support for projects around the state such as traffic projections for engineering design projects and... more
The New Mexico Statewide Travel Demand Model (NMSTDM) has served a number of purposes since its initial development, providing support for projects around the state such as traffic projections for engineering design projects and Intermodal/Inland Port Facilities, and scenario testing project analysis for New Mexico Department of Transportation (NMDOT) Districts. The statewide model matters. A national research group forecasts that in 2017, $109 billion in goods will have been shipped to and from New Mexico, predominantly by trucks
(TRIP - A National Transportation Research Group, 2017). The average driver in the Albuquerque area loses 36 hours per year, and the Santa Fe driver about 19 hours due to congestion. New Mexico’s population reached 2.1 million in 2015, which is a 15% increase since 2000. Vehicle Miles Traveled (VMT) has increased by 16% from 2000 to 2015. For the same period, New Mexico’s gross domestic product increased by 24%, compared to 27% for the US. We expect New Mexico VMT will increase by 20% by 2030 (TRIP - A National Transportation Research Group, 2017). If the NMSTDM is to continue to serve the state’s needs and be able to provide support for planned infrastructure projects, the model must be updated, expanded and enhanced. This report addresses the way we should improve the NMSTDM.
Consultants have supported modeling development and operations at NMDOT since 2008, but most recent support has been by one individual. So it is time to evaluate the state model and its platform. This report evaluates the current model and recommends improvements.
This report reviews national practices for State DOT travel demand models, different modeling platforms, various data sources available, the most common modeling concepts, and evaluates the NMSTDM. It concludes with specific recommendations on how the NMSTDM should be improved.
(TRIP - A National Transportation Research Group, 2017). The average driver in the Albuquerque area loses 36 hours per year, and the Santa Fe driver about 19 hours due to congestion. New Mexico’s population reached 2.1 million in 2015, which is a 15% increase since 2000. Vehicle Miles Traveled (VMT) has increased by 16% from 2000 to 2015. For the same period, New Mexico’s gross domestic product increased by 24%, compared to 27% for the US. We expect New Mexico VMT will increase by 20% by 2030 (TRIP - A National Transportation Research Group, 2017). If the NMSTDM is to continue to serve the state’s needs and be able to provide support for planned infrastructure projects, the model must be updated, expanded and enhanced. This report addresses the way we should improve the NMSTDM.
Consultants have supported modeling development and operations at NMDOT since 2008, but most recent support has been by one individual. So it is time to evaluate the state model and its platform. This report evaluates the current model and recommends improvements.
This report reviews national practices for State DOT travel demand models, different modeling platforms, various data sources available, the most common modeling concepts, and evaluates the NMSTDM. It concludes with specific recommendations on how the NMSTDM should be improved.
Research Interests:
Microscopic traffic simulation models are considered to be valuable and powerful tools for analyzing traffic operations in a wide range of planning and modeling tasks. However, modeling large-scale urban traffic networks is particularly... more
Microscopic traffic simulation models are considered to be valuable and powerful tools for analyzing traffic operations in a wide range of planning and modeling tasks. However, modeling large-scale urban traffic networks is particularly challenging task even on a macroscopic level.
The challenges are multifold when attempting to represent large urban networks in high-fidelity manner with operational details. While many previous studies proposed various simulation model calibration and validation methods, these processes are still considered to be more an art than science, especially if performed manually. This study describes such a manually-crafted simulation building, calibration and validation process that features a major urban grid network, encompassed with 6 busy arterials and 160 signalized intersections. A VISSIM model was calibrated and validated by using variety of traffic data, from two temporally, spatially, and characteristically different field data-collection campaigns. The accuracy and sensitivity of the model was repetitively fine-tuned and tested, until a chosen calibration criteria for several variables (volume, speed and travel times) was successfully met. Validation tests were performed with a completely fresh dataset at the end of the process. While the calibration efforts were a full success, the validation results were only half successful. Potential factors that could have impacted the mixed validation results are higher sensitivity of the validation data and seasonal shifts in traffic demand and distribution. Future research will focus on collecting and testing new validation data sets, which will improve robustness and reliability of the simulation model.
The challenges are multifold when attempting to represent large urban networks in high-fidelity manner with operational details. While many previous studies proposed various simulation model calibration and validation methods, these processes are still considered to be more an art than science, especially if performed manually. This study describes such a manually-crafted simulation building, calibration and validation process that features a major urban grid network, encompassed with 6 busy arterials and 160 signalized intersections. A VISSIM model was calibrated and validated by using variety of traffic data, from two temporally, spatially, and characteristically different field data-collection campaigns. The accuracy and sensitivity of the model was repetitively fine-tuned and tested, until a chosen calibration criteria for several variables (volume, speed and travel times) was successfully met. Validation tests were performed with a completely fresh dataset at the end of the process. While the calibration efforts were a full success, the validation results were only half successful. Potential factors that could have impacted the mixed validation results are higher sensitivity of the validation data and seasonal shifts in traffic demand and distribution. Future research will focus on collecting and testing new validation data sets, which will improve robustness and reliability of the simulation model.
Research Interests:
Left-turns are one of the most critical maneuvers at signalized intersections. There are several types of left turn signal phasing in use: protected-only, permitted/protected, permitted-only, and prohibited. If the protected part of a... more
Left-turns are one of the most critical maneuvers at signalized intersections. There are several types of left turn signal phasing in use: protected-only, permitted/protected, permitted-only, and prohibited. If the protected part of a left turn phase is assigned before the through phase starts, a left-turn sequence is called lead. If the opposite is true, it is called lag. Currently there are no uniform guidelines on left-turn installations. Furthermore, the practice on left-turns is not consistent. This paper summarizes a literature on left turn phasing, sequencing and left-turn signal displays (e.g., flashing yellow arrows) and points out the key findings and shortcomings. The authors propose computational and simulation tools – driving simulators, microsimulation, surrogate safety models and augmented reality for future research which could lead toward the unification of left-turn set of guidelines.
Research Interests:
Several factors are usually considered when recommending left-turn phasing at signalized intersections: the volume of through traffic opposing the left-turn maneuvers, the volume of left-turn traffic, the speed of the opposing traffic,... more
Several factors are usually considered when recommending left-turn phasing at signalized intersections: the volume of through traffic opposing the left-turn maneuvers, the volume of left-turn traffic, the speed of the opposing traffic, sight distance, crash history, and cycle length. The goal of this paper is to find the optimal signal phasing designs that can improve efficiency and safety of the particular signal design in the field in order to test current recommendations and guidelines on left-turn treatments. The researchers assess the impact of the number of rings in a phasing structure, the number of phases and whether to adopt lead or lag phasing on the safety and efficiency of a four-legged signalized intersection. A comprehensive set of 338 signal phasing designs is developed and the impacts are modeled using VISSIM microsimulation. The efficiency of signal phasing sets is evaluated in VISSIM, while the safety aspect is assessed using SSAM software. Optimal scenarios are tested using sensitivity analysis for various traffic flows. The findings show that the current left-turn guidelines may over-protect left-turners which results in reduced efficiency and left-turn delays that can be increased by up to 25%. Revised guidelines should contribute to the decreased delays for left turning vehicles, while keeping the safety standards high.
Research Interests:
Traffic Management Centers require dedicated management and staff with specialized skills and training. They rely on advanced technologies and require operating and capital funding. Investments in new technologies and services should... more
Traffic Management Centers require dedicated management and staff with specialized skills and training. They rely on advanced technologies and require operating and capital funding. Investments in new technologies and services should allow agencies to proactively manage and control traffic to optimize performance of a surface transportation system. The Utah Department of Transportation has commissioned a study to identify potential technological and service improvements for its TMC. The goal was to synthesize the current state of practice on applying innovative and advanced procedures, applications, and tools in TMC operations. This paper presents a summary of a broad web-based survey of transportation agencies and field visits to TMC agencies whose practices were recognized as most interesting for UDOT. The survey contained 22 questions which were developed for UDOT’s need to investigate improvement areas in its own operations. After reviewing responses from 54 agencies, a technica...
Research Interests:
Research Interests:
The New Mexico Statewide Travel Demand Model (NMSTDM) has served a number of purposes since its initial development, providing support for projects around the state such as traffic projections for engineering design projects and... more
The New Mexico Statewide Travel Demand Model (NMSTDM) has served a number of purposes since its initial development, providing support for projects around the state such as traffic projections for engineering design projects and Intermodal/Inland Port Facilities, and scenario testing project analysis for New Mexico Department of Transportation (NMDOT) Districts.
This report reviews national practices for State DOT travel demand models, different modeling platforms, various data sources available, the most common modeling concepts, and evaluates the NMSTDM. It concludes with specific recommendations on how the NMSTDM should be improved.
This report reviews national practices for State DOT travel demand models, different modeling platforms, various data sources available, the most common modeling concepts, and evaluates the NMSTDM. It concludes with specific recommendations on how the NMSTDM should be improved.
Research Interests:
Highway Capacity Manual (HCM) 2010 methodology for freeway operations contain procedures for calculating traffic performance measures both for undersaturated and oversaturated flow conditions. However, one of the limitations regarding... more
Highway Capacity Manual (HCM) 2010 methodology for freeway operations contain procedures for calculating traffic performance measures both for undersaturated and oversaturated flow conditions. However, one of the limitations regarding oversaturated freeway weaving segments is that the HCM procedures have not been extensively calibrated based on field observations on U.S. freeways. This study validates
the HCM2010 methodology for oversaturated freeway weaving segment by comparing space mean speed and density obtained from HCM procedure to those generated by a microsimulation model. A VISSIM model is extensively calibrated and validated based on NGSIM field data for the US 101 Highway. Abundance of the NGSIM data is utilized to calibrate and validate the VISSIM model. Results show that HCM methodology has
significant limitations and while in some cases it can reproduce density correctly, the study finds that speeds estimated by the HCM methodology significantly differ from those observed in the field.
the HCM2010 methodology for oversaturated freeway weaving segment by comparing space mean speed and density obtained from HCM procedure to those generated by a microsimulation model. A VISSIM model is extensively calibrated and validated based on NGSIM field data for the US 101 Highway. Abundance of the NGSIM data is utilized to calibrate and validate the VISSIM model. Results show that HCM methodology has
significant limitations and while in some cases it can reproduce density correctly, the study finds that speeds estimated by the HCM methodology significantly differ from those observed in the field.
Research Interests:
Traffic Operation Centers (TOCs) require dedicated management and staff with specialized skills and training. They also rely on advanced technologies and require dedicated operating and capital funding. Each new investment in TOC‟s... more
Traffic Operation Centers (TOCs) require dedicated management and staff with specialized skills and training. They
also rely on advanced technologies and require dedicated operating and capital funding. Each new investment in TOC‟s technologies and/or services should allow agencies to proactively manage and control traffic in a manner that
optimizes the performance of a surface transportation system. The Utah Department of Transportation (UDOT) has
commissioned a study to identify potential technological and service improvements for UDOT Traffic Management Center (TMC). The goal of the study is to synthesize the current state of practice on applying innovative and advanced procedures, applications, and tools in operations of TMCs. This report presents outcomes from such a study which was divided into two major phases: a broad web-based survey of the selected agencies and a set of field visits to few of those agencies-leaders in TOC operations. The web based survey was administered through SurveyGizmo during April and May of 2012. Survey contained 22 questions which were developed in accordance
with UDOT needs to investigate improvements areas in its TOC operations. After reviewing responses from 54 agencies UDOT technical advisory team selected a list of TMCs which were good candidates to interview during a field visit. Two field-visit tours were organized. The first one was a tour of “Eastern States” TMCs between June 4th and 7th, during which TMCs of following DOTs were visited: Minnesota, Pennsylvania, Ohio, and Virginia. The second tour visited “Western States” TMCs, from July 9th to 11th, when the UDOT team visited California Department of Transportation (CALTRANS) offices in Sacramento and San Francisco and Kansas City SCOUT in Missouri. A literature review of some of the most prominent TMCs in the world shows some interesting international applications which may show directions in which US TMCs will go in near future. The report is
summarized through the best TMC practices from the field visits and literature review by providing a comprehensive list of the highlights at the end of the report (Chapter 6).
also rely on advanced technologies and require dedicated operating and capital funding. Each new investment in TOC‟s technologies and/or services should allow agencies to proactively manage and control traffic in a manner that
optimizes the performance of a surface transportation system. The Utah Department of Transportation (UDOT) has
commissioned a study to identify potential technological and service improvements for UDOT Traffic Management Center (TMC). The goal of the study is to synthesize the current state of practice on applying innovative and advanced procedures, applications, and tools in operations of TMCs. This report presents outcomes from such a study which was divided into two major phases: a broad web-based survey of the selected agencies and a set of field visits to few of those agencies-leaders in TOC operations. The web based survey was administered through SurveyGizmo during April and May of 2012. Survey contained 22 questions which were developed in accordance
with UDOT needs to investigate improvements areas in its TOC operations. After reviewing responses from 54 agencies UDOT technical advisory team selected a list of TMCs which were good candidates to interview during a field visit. Two field-visit tours were organized. The first one was a tour of “Eastern States” TMCs between June 4th and 7th, during which TMCs of following DOTs were visited: Minnesota, Pennsylvania, Ohio, and Virginia. The second tour visited “Western States” TMCs, from July 9th to 11th, when the UDOT team visited California Department of Transportation (CALTRANS) offices in Sacramento and San Francisco and Kansas City SCOUT in Missouri. A literature review of some of the most prominent TMCs in the world shows some interesting international applications which may show directions in which US TMCs will go in near future. The report is
summarized through the best TMC practices from the field visits and literature review by providing a comprehensive list of the highlights at the end of the report (Chapter 6).