Transportation Engineering Commons^™

Choosing The Optimal Scheme Of Placement Of Thermal Trains On The Chart Of The Movement Of Trains, Muslimа Djalalovna Akhmedova, Dilmurod Baхodirovich Butunov, Sardor Askarovich Abdukodirov

Journal of Tashkent Institute of Railway Engineers

To analyze the methods of selecting the optimal scheme of layout of thermal trains at railway stations. Graphic and mathematical modeling methods are used. The factors influencing the selection of the optimal train schedule have been identified.Existing trains of thermal trains have been analyzed the schemes and mathematical formulas have been developed. Frequently used mathematical formulas at the railway stations, thermal trains create smooth and efficient traffic, and the train traffic destroys the possibility of direct adjustment.

To The Question Of Dispatching Regulation Of Overtaking Freight Trains, Samandar Bahtiyorovich Sattorov, Ruslanovna Ibragimova Gulshan, Daurenbek Ihtiyarovich Ilesaliev

Journal of Tashkent Institute of Railway Engineers

This article discusses the problems of the influence of accelerated freight trains on station and distillation intervals, as well as on a simple freight train under overtaking. The relevance of this article is due to the fact that irrational dispatch regulation of overtaking of freight trains with accelerated trains negatively affects the throughput of the railway line.

Linking Train Schedule Assignments To A Solid Schedule, Alexander Aleksanlrovich Svetashev, Nodir Qodirovich Aripov, Nargiza Faritovna Svetasheva

Journal of Tashkent Institute of Railway Engineers

The article provides an analysis of the composition of the sorting station during the accumulation of trains and the formation of trains with their departure on a solid schedule in order to establish dependencies that allow you to determine the cost of wagon-hours for the accumulation of cars and the rationale for the use of a solid schedule. The paper highlights the features of the process of accumulation of cars with a solid schedule as opposed to accumulation with a flexible schedule. As a result of modeling the composition of the solid schedule, the necessary parameters were calculated, which were …

Results Of Application Of The Methods “Conditional Group Sorting” And “Combinatorial Sorting” Duringthe Multi-Group Trains Formation, Sakijan Kabildjanovich Khudayberganov, Shinpolat Mansuraliyevich Suyunbayev, Alfiya Mirkhatimovna Bashirova, Sherzod Bakhromugli Jumayev

Journal of Tashkent Institute of Railway Engineers

At present, the formation of multi-group freight trains on the sorting stations is the actual issue. The main raisons are: there is no exact (developed) technology, in order to form multi-group trains on the sort stations and also, formation of such type of trains according to the established procedure based on many years of experience of the relevant personnel. In this article, the results of the applied methods are presented “Conditional group sorting” and “Combinatorial sorting” during the multi-group trains formation on the sorting station JSC Uzbek Railways. The efficiency of the method “Conditional group sorting” has been revealed regarding …

Three-Way Thermal Model Of Asynchronous Traction Engines For Diagnostics Of Their Technical Condition, Zhavkharbek Sulton Ugli Fayzullaev

Journal of Tashkent Institute of Railway Engineers

Mathematical models of the thermal processes of traction induction motors are developed. An induction motor is considered as a thermal system consisting of three bodies (stator winding, stator magnetic circuit and rotor), in which heat transfer is taken into account not only between the respective bodies, but also heat transfer between each body and the environment. It is shown that the steady-state excess of the stator winding temperature of a traction induction motor depends on the multiplicity of the stator winding current, the coefficient of electrical energy loss, and also on the temperature coefficient of resistance of the material of …

An Example Of Calculating The Speed Of The Railway Carriage On The Accelerating Slope Of The Hump, Shukhrat Batirovich Djabbarov

Journal of Tashkent Institute of Railway Engineers

The paper content is based on classic provisions of mechanics (D’Alembert principle) for non-ideal communication. The authors provide with the analytical proof of that the linear acceleration of the car when it is uniformly accelerated along the descending part of the hump depends on the force that affects the car to roll down the slope of the hump, on the force of resistance of all kinds, on the adjusted weight of the car with load taking into account the moment of flywheel action. At the same time, the results of calculations prove that the rotating parts weight practically does not …

Over Height Impact Avoidance And Incident Detection System, Suvash Chapain, Aly Mousaad Aly

Faculty Publications

During the construction and repair of bridges, work platforms or construction-related containment may result in restricted vertical clearances at a work location. Some tractor-trailer combinations are prone to over-height collisions at these locations. Collisions are a hazard to all drivers, and repair of the damage typically causes traffic delays. Appropriate solutions to this problem will focus on the prevention of collisions by detecting over-height vehicles and directing the drivers to take an alternate safe route. This presentation addresses the design and functionality of smart detection/alert systems that can be set up well in advance of a known vertical clearance restriction …

Developing A Baseline For Customer Satisfaction In The Kentucky Transportation Cabinet's Department Of Vehicle Regulation, Steven Andrew Martin, Christopher W. Van Dyke, Jennifer R. Walton, Jeeyen Koo, Valerie Keathley Helil, Brian K. Howell

Kentucky Transportation Center Research Report

Among the Kentucky Transportation Cabinet’s (KYTC) business units, the Department of Vehicle Regulation (DVR) has the most interactions with members of the public and other government agencies. Given its high profile and public visibility, it is critical for the department to provide high-quality customer service. Lacking data on customer perceptions of DVR’s level of service, the department commissioned researchers at the Kentucky Transportation Center (KTC) to conduct a baseline and rebaseline customer satisfaction surveys. Along with administering surveys to external customers, KTC’s research team also polled DVR staff to gauge employee morale and identify areas which could be improved. Approximately …

Guidelines For Using Streetlight Data For Planning Tasks, Hong Yang, Mecit Cetin, Qingyu Ma

Computational Modeling & Simulation Engineering Faculty Publications

The Virginia Department of Transportation (VDOT) has purchased a subscription to the StreetLight (SL) Data products that mainly offer origin-destination (OD) related metrics through crowdsourcing data. Users can manipulate a data source like this to quickly estimate origin-destination trip tables. Nonetheless, the SL metrics heavily rely on the data points sampled from smartphone applications and global positioning services (GPS) devices, which may be subject to potential bias and coverage issues. In particular, the quality of the SL metrics in relation to meeting the needs of various VDOT work tasks is not clear. Guidelines on the use of the SL metrics …

Finding Patterns In Subsurface Using Bayesian Machine Learning Approach, Wang Hui

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Stochastic simulation approaches and uncertainty quantification are usually adopted for gaining insight into variability in soil stratigraphy configurations. Previous investigations at geotechnical site characterization and interpretation can be broadly categorized into geostatistics- and process-based methods. On the other hand, modern site exploration techniques provide high-quality, dense datasets in physical spaces with high resolution, either directly from sensors (for example, cone penetration testing data) or indirectly from geophysical inversion (such as seismic inversion, electromagnetic induction inversion, and ground penetrating radar). In this work, anisotropy and heterogeneity are considered as possible patterns that inherently exist in the observations, and these are inferred …

Improvement Of Low Traffic Volume Gravel Roads In Nebraska, Richard L. Wood, Yong-Rak Kim, Yijun Liao, Mohammad E. Mohammadi

Nebraska Department of Transportation: Research Reports

In the state of Nebraska, over one-third of roadways are unpaved, and consequently require a significant amount of financial and operational resources to maintain their operation. Undesired behavior of surface gravel aggregates and the road surfaces can include rutting, corrugation, and ponding that may lead to reduced driving safety, speed or network efficiency, and fuel economy. This study evaluates the parameters that characterize the performance and condition of gravel roads overtime period related to various aggregate mix designs. The parameters, including width, slope, and crown profiles, are examples of performance criteria. As remote sensing technologies have advanced in the recent …

Synthesis Of Repair Practices Of Damaged Precast/Prestressed Concrete Girders, George Morcous, Richard L. Wood, Antony Mohsen Kamal Masoud Kodsy

Nebraska Department of Transportation: Research Reports

Bridge girders are constantly subjected to various types of damage during their service life. There is currently limited knowledge or guidelines provided by the NDOT Bridge Office Policies and Procedures (BOPP) regarding the assessment and repair procedures of damaged precast/prestressed concrete girders. This report aims to develop a comprehensive repair manual for precast/prestressed concrete girders subjected to damage caused by over-height vehicular collision and damage located at the girder ends. Over-height vehicular collision damage typically occurs at the middle portion of the exterior girders and the primary concerns are focused on flexural deficiencies. Girder end damage can occur due to …

Performance Of Us Concrete Highway Bridge Decks Characterized By Random Parameters Binary Logistic Regression, Omar Ghonima, Jason C. Anderson, Thomas Schumacher, Avinash Unnikrishnan

Civil and Environmental Engineering Faculty Publications and Presentations

This study employs a random parameters binary logistic regression (LR) to characterize the impact of environmental and structural parameters on concrete highway bridge deck deterioration nationwide. Two specific gaps in the literature are addressed: (1) the use of a nationwide dataset for analysis, and (2) the implementation of a methodology to account for unobserved heterogeneity. A total of 3,262 bridge deck deterioration observations derived from the authors’ nationwide concrete highway bridge deck performance inventory (NCBDPI) database were used in this study. The deterioration rate (DR) was computed as the decrease in the concrete bridge deck condition rating ( …

Analysis Of Crashes Involving First Responder Vehicles, Josie Gray

Doctoral Dissertations and Master's Theses

First responders face many hazards that put their lives at risk while on duty. A review of the National Law Enforcement Officers Memorial Fund statistics shows that 553 police officers died in the line-of-duty between 2008 and 2017 as a direct result of a traffic related incidents. Sadly, the nation’s first responders are exposed to factors which make them uniquely vulnerable to traffic related injuries and deaths. The goal of this research is to investigate and analyze crashes involving first responder vehicles and struck-by crashes. This project concludes that approximately 1.2% of the crashes in the state of Florida involve …

Crime And Harassment On Public Transportation: A Survey Of Sjsu Students Set In International Context, Asha Weinstein Agrawal, Anastasia Loukaitou-Sideris, Cristina Tortora, Yajing Hu

Mineta Transportation Institute

Communities around the world are gradually becoming aware that transit riders, and especially women, are often victims of a wide range of offenses of a sexual nature that happen on buses and trains, and at bus stops and train stations. Better understanding the extent and nature of sexual harassment on transit is a critical issue for transit operators and society at large. If fear of sexual crime limits if and how people ride transit, the result is reduced mobility for certain segments of the population, as well as lost ridership for transit agencies.

For this study, we surveyed 891 students …

Developing A Computer Vision-Based Decision Support System For Intersection Safety Monitoring And Assessment Of Vulnerable Road Users, Arash Jahangiri, Anagha Katthe, Aryan Sohrabi, Xiaobai Liu, Shashank Pulagam, Vahid Balali, Sahar Ghanipoor Machiani

Mineta Transportation Institute

Vision-based trajectory analysis of road users enables identification of near-crash situations and proactive safety monitoring. The two most widely used sur-rogate safety measures (SSMs), time-to-collision (TTC) and post-encroachment time (PET)—and a recent variant form of TTC, relative time-to-collision (RTTC)—were investigated using real-world video data collected at ten signalized intersections in the city of San Diego, California. The performance of these SSMs was compared for the purpose of evaluating pedestrian and bicyclist safety. Prediction of potential trajectory intersection points was performed to calculate TTC for every interacting object, and the average of TTC for every two objects in critical situations was …

A New Materials And Design Approach For Roads, Bridges, Pavement, And Concrete, Alan Fuchs, Tathagata Acharya, Luis Cabrales, Jesse Bergkamp, Nyakundi Michieka

Mineta Transportation Institute

Increased understanding of demand for transport energy and how to improve road pavement materials would enable decision makers to make environmental, financial, and other positive changes in future planning and design of roads, bridges, and other important transportation structures. This research comprises three studies focused on pavement materials and a fourth study that examines energy demand within the road transportation sector. These studies are as follows:

1. A techno-economic study of ground tire rubber as an asphalt modifier;

2. A computational fluid dynamics analysis comparing the urban heat island effect of two different pavement materials – asphalt and Portland Cement …

Analysis And Assessment Of The Reimbursement Rates And Mechanisms For Kentucky’S Publicly Funded Ferries, P. Gayle Marks, Bryan Gibson, Andrew Martin, Steven Douglas Kreis

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet (KYTC) reimburses publicly operated ferries, including when they cease operations due to severe weather or unforeseen events. Reimbursement procedures are not codified in law and are largely based on historical practice. To determine how the Cabinet should handle reimbursement, funding, oversight of ferry services moving forward, the Kentucky Transportation Center (KTC) reviewed practices adopted by 10 other states and conducted a detailed analysis of Kentucky’s current approach. Of the states KTC examined, only Tennessee reimburses ferry operations for closures (at 50 percent of the normal hourly rate for a period up to 48 hours). Half of …

Improving Construction Work Zone Safety Using Technology: A Systematic Review Of Applicable Technologies, Chukwuma Nnaji, John Gambatese, Hyun Woo Lee, Fan Zhang

Faculty Publications

© 2019 The Authors Once considered conventional, the construction industry is gradually increasing its reliance on innovations such as the application of technologies in safety management. Given the growing literature on technology applications in safety management and the varying opinions on the utility of applied technologies, a systematic review that streamlines findings from past studies is indispensable to construction stakeholders. Although a number of review studies are available in the building construction sector, the level of fragmentation and uniqueness within the construction industry necessitates a review study specifically targeting the heavy civil sector. In response, the present study applies a …

The Potential For Autonomous Vehicle Technologies To Address Barriers To Driving For Individuals With Autism, Caroline Rodier

Mineta Transportation Institute

Individuals with autism represent a sizeable share of the U.S. population (almost 2%), and nearly half of those with autism have average to high levels of intelligence. However, available research shows that adults with autism have a much more difficult time becoming employed and living independently compared to both typically developing adults and adults with disabilities. This study reviews the available literature on the magnitude of challenges to driving and accessing essential opportunities for adults with autism, and the potential of autonomous vehicles to address those challenges. This study is unique in that it identifies the specific driving challenges and …

A Smart Growth & Equity Framework And Tool For Measuring, Understanding, And Realizing Transportation Land Use Coordination For Sustainability, Livability, And Equity, Bruce Appleyard, Chris Allen, Jonathan Stanton

Mineta Transportation Institute

The coordination and integration of transportation and land use (also known as “smart growth”) has been a long-standing goal for planning and engineering professionals, but to this day remains an elusive concept to realize. As this approach is a widely recognized as key to achieving sustainable, livable, and equitable (SLE) outcomes for individuals and society, a key aim of this report is to instill the coordination of transportation and land use into practice by the collection of key actors and agents (MPOs, DOTs, and local land use authorities, etc.) through new measurement and policy guidance frameworks and tools. A fundamental …

Early Detection Of Near-Surface Void Defects In Concrete Pavement Using Drone Based Thermography And Gpr Methods, Zhigang Shen, Ece Erdogmus, George Morcous, Chngsheng Cheng, Zhexiong Shang, Theresa Mccabe, Antony Mohsen Kamal Masoud Kodsy

Nebraska Department of Transportation: Research Reports

The goal of this research is to evaluate the feasibility and the performance of using UAV-mounted infrared thermography (IRT) and ground penetration radar (GPR) to detect sub-surface voids caused by consolidation issues in concrete pavement. The motivation of the study is to identify the consolidation defects as early as the initial set of concrete to avoid having this problem in large pavement sections, which is costly and time consuming to repair. Using the two technologies in combination to detect subsurface voids in the concrete initial set stage is new and aims to take advantage of the strengths and minimize the …

Optfill: A Tool For Infeasible Cycle-Free Gapfilling Of Stoichiometric Metabolic Models, Wheaton L. Schroeder, Rajib Saha

Mid-America Transportation Center: Final Reports and Technical Briefs

Stoichiometric metabolic modeling, particularly genome-scale models (GSMs), is now an indispens- able tool for systems biology. The model reconstruction process typically involves collecting informa- tion from public databases; however, incomplete systems knowledge leaves gaps in any reconstruc- tion. Current tools for addressing gaps use databases of biochemical functionalities to address gaps on a per-metabolite basis and can provide multiple solutions but cannot avoid thermodynami- cally infeasible cycles (TICs), invariably requiring lengthy manual curation. To address these limita- tions, this work introduces an optimization-based multi-step method named OptFill, which performs TIC-avoiding whole-model gapfilling. We applied OptFill to three fictional prokaryotic models …

Calibrating The Highway Capacity Manual Arterial Travel Time Reliability Model, Ernest Tufuor, Laurence Rilett, Li Zhao

Mid-America Transportation Center: Final Reports and Technical Briefs

The latest edition of the Highway Capacity Manual (HCM-6) includes, for the first time, a methodology for estimating and predicting the average travel time distribution (TTD) of urban streets. Travel time reliability (TTR) metrics can then be estimated from the TTD. The HCM-6 explicitly considers five key sources of travel time variability. A literature search showed no evidence that the HCM-6 TTR model has ever been calibrated with empirical travel time data. More importantly, previous research showed that the HCM-6 underestimated the empirical TTD variability by 70% on a testbed in Lincoln, Nebraska. In other words, the HCM-6 TTR metrics …

Analysis Of Component Errors In The Highway Capacity Manual Travel Time Reliability Estimations For Urban Streets, Ernest Tufuor, Laurence Rilett

Mid-America Transportation Center: Final Reports and Technical Briefs

The Highway Capacity Manual 6th edition (HCM6) includes a new methodology to estimate and predict the distribution of average travel times (TTD) for urban streets. The TTD can then be used to estimate travel time reliability (TTR) metrics. Previous research on a 0.5-mi testbed showed statistically significant differences between the HCM6 estimated TTD and the corresponding empirical TTD. The difference in average travel time was 4 s that, while statistically significant, is not important from a practical perspective. More importantly, the TTD variance was underestimated by 70%. In other words, the HCM6 results reflected a more reliable testbed than field …

Análisis Por Confiabilidad Del Modelo De Diseño Aashto 93 Para Pavimentos Flexibles En El Valle De Aburrá, Mario Santiago Hernández, Juan Pablo Osorio, Juan Camilo Viviescas

Books/Book Chapters

La necesidad de construir pavimentos con mejores especificaciones técnicas y mayores períodos de servicio requiere de una modelación rigurosa de la variabilidad en las propiedades geotécnicas con el fin de garantizar la confiabilidad de estas estructuras. Por lo tanto, se realizó un análisis basado en la confiabilidad del método Aashto-93, considerando la variabilidad geotécnica del suelo, asociada al módulo resiliente de la subrasante. Los diseños por confiabilidad fueron efectuados de acuerdo con las categorías, parámetros y estructuras establecidas por el Manual de diseño de pavimentos asfálticos en vías con medios y altos volúmenes de tránsito, de 1998, del Instituto Nacional …

An Integrated Computational And Experimental Study To Investigate Staphylococcus Aureus Metabolism, Mohammad Mazharul Islam, Vinai C. Thomas, Matthew Van Beek, Jong-Sam Ahn, Abdulelah A. Alqarzaee, Chunyi Zhou, Paul D. Fey, Kenneth W. Bayles, Rajib Saha

Mid-America Transportation Center: Final Reports and Technical Briefs

Staphylococcus aureus is a metabolically versatile pathogen that colonizes nearly all organs of the human body. A detailed and comprehensive knowledge of staphylococcal metabolism is essential to understand its pathogenesis. To this end, we have reconstructed and experimentally validated an updated and enhanced genome-scale metabolic model of S. aureus USA300_FPR3757. The model combined genome annotation data, reaction stoichiometry, and regulation information from biochemical databases and previous strain-specific models. Reactions in the model were checked and fixed to ensure chemical balance and thermodynamic consistency. To further refine the model, growth assessment of 1920 nonessential mutants from the Nebraska Transposon Mutant Library …

On-Site Measurement Of The Water-Cementitious Ratio And Heat Of Hydration Of Delivered Concrete, Seyednavid Mardmomen

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this study, AASHTO T318-15 was adopted to estimate the water content of fresh concrete mixes and then revised to have better precision. The additional step required sieving out the coarse aggregate after drying the sample in a microwave oven, and it was then used in the calculation of the absorbed water and cementitious material content. Several laboratory batches, as well as on-site water-cementitious (w/cm) ratio tests, were performed on concrete mixes containing ordinary Portland cement, ground granulated blast furnace slag, and Class F fly ash. The results of the experiments indicated that the accuracy of the revised method was …

Impacts Of Bike Sharing On Transit Ridership, Moathe Salah Aljeri

Graduate Theses, Dissertations, and Problem Reports (ETD)

Biking is an active, environmentally friendly, and sustainable transportation mode that facilitates short utilitarian and recreational trips. As such, cities around the world have been implementing bicycle sharing/renting programs at stations in a wide network so that a traveler can mount one close to their origins and drop it off at a station nearest to their destinations. In addition, bike sharing programs can solve the first-mile and last-mile connectivity problems of transit modes. Such programs also enable short trips that were previously impossible without using transit modes. This research investigated the relationship between New York City (NYC) subway ridership and …

Impact Of Smart Phones’ Interaction Modality On Driving Performance For Conventional And Autonomous Vehicles, Francesca M. Favarò

Mineta Transportation Institute

Distracted driving related to cell phone usage ranks among the top three causes of fatal crashes on the road. Although forty-eight of 50 U.S. states allow the use of personal devices if operated hands-free and secured in the vehicle, scientific studies have yet to quantify the safety improvement presumed to be introduced by voice-to-text interactions. Thus, this study investigated how different modes of interaction of drivers with a smart phone (i.e., manual texting vs. vocal input) affect drivers’ distraction and performance in both conventional and semi-autonomous vehicles. The study was executed in a full-car integrated simulator and tested a population …