Transportation Engineering Research Articles

Road Damage Detection and Classification

Abstract: This is a road damage detection desktop application. In the subject of transportation engineering, identifying road damage early on is essential because it can save maintenance costs and avoid accidents. Deep learning methods have demonstrated encouraging performance in a number of computer vision tasks recently, including the detection of road damage. In this study, we suggest a region-based convolutional neural network (R-CNN)-based method for detecting road degradation. Using a publicly accessible dataset of road photos with different kinds of damage, such as cracks, potholes, and patches, we trained our R-CNN. Our approach outperformed cutting-edge techniques with an accuracy of 85% in identifying road damage.

Investigation of mechanical properties and microstructure characterisation of MMA-MIG-TIG-SAW welded EN8 steel joints via shot blasting method

The industries of energy, transportation, and other engineering components all benefit greatly from the use of medium carbon (C) steel EN8. For these applications, welding is typically used to join the material. Conventionally welded joints, however, struggle to meet the exacting standards of industrial applications. In this comprehensive study, the tensile strength, microhardness, and microstructure of joints made of medium C EN8 steel using manual metal arc (MMA), metal inert gas (MIG), tungsten inert gas (TIG), and submerged arc (SAW) welding were investigated. These weld joints were then subjected to the shot blasting method to determine the effect on the mechanical properties of these weldments, Different response characteristics have been studied in relation to the shot blasting with various time periods. A detailed characterisation of the samples has been carried out optical microscopy, surface electron microscopy (SEM), energy dispersive spectroscopy (EDS), optical emission spectroscopy (OES), microhardness, and tensile testing with fractographical analysis. The maximum percentage increase in the microhardness in fusion zone (FZ) occurred in case of TIG welded specimens, i.e. 29.63% after 25 min of abrasive blasting period. However, the maximum change in the tensile strength, i.e. 10.53% has been observed for MMA welded specimens after 15 min of abrasive blasting period. Microstructural analysis revealed TIG has a columnar dendritic structure, MIG and SAW have an equiaxed dendritic structure. MMA has a cellular dendritic structure. The outcomes revealed that abrasive blasting improves the mechanical characteristics of industrial MMA, MIG, TIG, and SAW welded specimens.

Highway Transportation, Health, and Social Equity: A Delphi-ANP Approach to Sustainable Transport Planning

It has become standard practice for governments and transportation engineers around the world to infuse sustainability principles into their plans as higher-level goals and priorities, with indicators to reflect the same. The transformation towards sustainable mobility should involve the three interconnected pillars of sustainable development: environment, social equity, and economy. These pillars, known in the business field as the ‘triple-bottom-line’, require specific indicators that can be used to measure the attainment of each pillar. There is evidence that the social equity impacts of construction projects, such as transport projects, and their distributional effects across various segments of society have traditionally been viewed as secondary or subsidiary concerns relative to their economic and environmental impacts. Recognizing the relative relegation in both academic and policy circles of social impacts and the ‘weak’ tools to identify such impacts, this research aims to employ a hybrid decision method based on the analytic network process and Delphi method to identify the major adverse impacts of highway automobiles on health and social equity in the UAE. In doing so, governments will be better positioned to mitigate adverse impacts through engineering, urban planning, technological, and other appropriate initiatives. Throughout the Delphi process, 15 health and social equity indicators have been validated by experts in the field of sustainability and transportation through an iterative process. Then, experts in the same field were chosen to develop and validate the ANP model based on the validated indicators through pairwise comparison questionnaires. The results and findings revealed that the experts’ judgment preferences are consistent (inconsistency value less than 0.1), wherein the highest priority is the ‘Safety’ indicator, and the lowest priority is the ‘Public participation in transport decision’ indicator.

Directional analysis of community wildfire evacuation capabilities

Wildfires are a natural part of forest ecosystems, but sometimes pose a threat to communities. In Canada, when public safety is threatened by a wildfire encroaching into the wildland-urban interface (WUI), fire management agencies will recommend that local authorities evacuate the area. If a fire spreads quickly towards a community and egress capacity is insufficient, public safety can be compromised. This paper presents an interdisciplinary approach for assessing community directional vulnerabilities for wildfire evacuation, combining techniques from wildland fire science and transportation engineering. For a selection of communities in Alberta that were assessed as being potentially vulnerable to wildfire, we explored the directional configuration of the transportation network in relation to a directional assessment of wildfire exposure. We first plotted the viable fire pathways and transportation facility characteristics, and then compared estimated fire encroachment times against estimated community egress times, directionally around each community to show evacuation vulnerabilities. Our results show that some communities, mainly within the Boreal Forest, Foothills and Rocky Mountain natural regions, have egress routes that are highly exposed to potential wildfire encroachment. Our findings also indicate that the evacuation timing for some larger communities needs attention, given relationships between estimated fire travel times and evacuation times. The results can be used to inform evacuation preparedness planning and proactive mitigation efforts.

An activity space-based gravity model for intracity human mobility flows

Modeling and estimating urban human mobility flows is significant to multidisciplinary applications such as transportation engineering, urban planning and epidemic prevention. In recent decades, a wide range of trip distribution models for urban human mobility flows have been developed, among which the gravity model is the most classic and widely used. However, like most of the existing trip distribution models, the original gravity model adopts population as the proxy of urban region's attractiveness, which could not fully reflect the urban region's attractiveness as well as its temporal dynamics. Moreover, the original gravity model depends on the selection of proper distance decay functions, which require context-specific adjustable parameters derived from empirical mobility data. Taking advantage of the notion of activity space, we innovatively develop a proxy of urban region's attractiveness, and further propose a new activity space-based gravity (ASG) model. The case study results show that the ASG model significantly outperforms the original gravity model in estimating the overall human mobility flows and the hourly human mobility flows between urban regions. This study contributes to the state-of-the-art understanding of urban human mobility and human mobility flow modeling. The findings also provide insights into transportation management, infrastructure development and urban planning.

Bibliometric analysis of carsharing and car rental research in the field of urban transportation and tourism transportation

This paper reviews recent carsharing and car rental research bibliometrically. The study examines the evolution, structure, and boundaries of Web of Science-reviewed carsharing and car rental research. VOSviewer and SPSS 22 evaluated 204 vehicle rental and 574 carsharing articles in the WOS core collection. A gradual rise in car rental and carsharing studies is shown. China and the US produce the most carsharing and rental publications, respectively. China is the most productive country for carsharing publications and the United States for car rental publications. While China and the United States cooperate on carsharing, the United States cooperates with other countries (Canada, Germany, England, France, Australia, Portugal, Taiwan, Israel) on car rental. Co-occurrence network analysis shows that carsharing has five main themes: sharing economy, electric vehicles, transportation, shared mobility, and mobility as a service, while car rental research has four main themes: revenue management, transportation, quality service, and e-commerce. Carsharing and car rental studies share transportation themes. Carsharing subjects include transportation, engineering, business economics, environmental science ecology, science technology, and computer science, while car rental subjects include management, operations research, economics, transportation, business, transportation science technology, business finance, engineering, tourism, and environmental science. Car rental concerns vary by management, tourism, and finance. Tourism literature neglects car hire. This study thoroughly reviews 26 years of automobile rental and 22 years of carsharing literature. Thus, it can help academics comprehend automobile rental and carsharing studies and direct future research.

Car-following model calibration with load effect as additional optimisation objective

Calibrating a car-following model is an essential component in the traffic load analysis of bridges, since the parameter set fundamentally determines the spatiotemporal distributions of the vehicles and the magnitude of the load effects. In bridge engineering, car-following models are adapted from transportation engineering so that they do not consider load effects in the calibration process. This paper proposes a novel framework that factors vehicle motions and load effects into a multi-objective optimisation problem to calibrate car-following models. The Intelligent Driver Model (IDM) and the Gipps’ model are introduced for comparison. In the testing, three different types and spans of bridges are selected to compare the models in terms of fitness, robustness, and compactness of the solution. Within the proposed framework, the Gipps’ model proves to be superior in terms of fitness but achieves poor performance in robustness, while the IDM exhibits the opposite pattern. The solution compactness of the Gipps’ model improves with higher truck weights only in the circumstance of the load effects type with a unimodal influence line. Overall, the Gipps’ model is recommended for analysis with abundant data. Otherwise, the IDM can be adopted for a non-optimal but robust result.

The Comprehensive Features, Current Aspects, Synthesis, Characterization and Role of Nanomaterials in Modern Industries through Nanotechnology

Nanotechnology has attained the valuable significant attention throughout time because to its compelling and pioneering uses in the forthcoming industrial age, particularly in relation to nanomaterials. Nanomaterials find applications in several areas, including agriculture, biomedicine, electronics, energy, transportation, communications, cosmetics, coatings, materials, and mechanical engineering. Numerous techniques have been used to fabricate nanoparticles (NPs) with precise control over their form, size, dimensions, and structure. There may be exist two primary methodologies for the synthesis of nanoparticles, namely the top-down and bottom-up techniques. These nanoparticles include core/shell (CS) nanoparticles, gold nanoparticles (Au-NPs), nickel nanoparticles (Ni-NPs), platinum nanoparticles (Pt-NPs), copper oxide nanoparticles (CuO-NPs), zinc oxide nanoparticles (ZnO-NPs), palladium nanoparticles (Pd-NPs), and silicon nanoparticles (Si). The physicochemical qualities may vary depending on the size and form of the object. There are many categories of nanocomposites, including ceramic matrix nanocomposites, metal matrix nanocomposites, and polymer matrix nanocomposites. Semiconductor materials have characteristics that lie between those of metals and nonmetals, making them very versatile and widely used in numerous applications, as documented in the literature. Semiconductor nanoparticles have broad bandgaps, resulting in notable modifications to their characteristics via bandgap tuning. Carbon nanotubes (CNTs) and graphene are widely recognized as prominent constituents within the carbon-based nanomaterials category. There are many aspects of the functional nanomaterial needed to explore their chemical and physical potentials for the use in the sub valuable industries areas.

Correlation Of Physical Fitness Factors, Body Mass Index, And Time Spent In Physical Activity Of Aims Maritime Students: Basis In The Preparation Of Agile And Resilient Cadets Onboard

This research aims to assess the current physical fitness status of maritime students and develop strategies to prepare them before their onboarding on international and local vessels. Physical conditioning is identified as the dependent variable, reflecting the general physical functioning and fitness of the respondents. The research hypothesizes that physical activity and BMI also play a significant role in predicting physical conditioning. A total of 212 respondents from the marine transportation and marine engineering programs were included in the study, predominantly male students aged 19-21, classified under the "lower middle-income" socioeconomic category. The results indicate that the respondents perceive themselves as having good muscular condition, flexibility, and body composition. The study reveals positive associations between muscular flexibility and condition, muscular flexibility and physical conditioning, and body composition and physical conditioning. Multiple regression analyses identified muscle flexibility, muscular condition, body composition, BMI, and time spent on physical activity as significant predictors of physical conditioning. Notably, small decreases in body composition and time spent on physical activity were associated with increased physical conditioning, emphasizing the importance of improving these variables to enhance physical health. In conclusion, this research provides insights into the physical fitness status of maritime students and identifies factors influencing their physical conditioning. The study highlights the contributions of muscular flexibility, muscular condition, body composition, physical activity, and BMI in maintaining good physical health among maritime students.

Integrating equity in transportation scenario planning: A systematic review

To address the growing uncertainties in the future transportation industry, planners and engineers have identified and implemented scenario planning, a multi-step and strategic approach, in long-range transportation planning. A comprehensive examination of how equity is envisioned, planned, and analyzed during this process remains absent, despite several key guidelines of scenario planning exercises. This paper conducts a systematic literature review focusing on how equity has been considered and evaluated in scenario planning. The resources include academic papers, agency reports, and materials from the recent scenario planning conference, the 2nd Conference on Scenario Planning in Transportation hosted by the Transportation Research Board. This paper examines equity in scenario planning in three important ways: 1) the ways equity has been integrated across steps; 2) how equity analysis has evolved; and 3) when it is necessary to consider equity. This work adds value to the existing body of knowledge by presenting the policy implications based on the review of the current scenario planning research and practices. Early policy recommendations include the need for more vertical equity evaluations, the construction of robustness and justice indicators, and the adoption of a flexible mindset of planning for rather than being fixated on a single scenario.

A global empirical study on how street networks facilitate driving longer distances

We simulated over 200 cities worldwide to investigate how the street network affects vehicle routes. We demonstrate that there is a ubiquitous super-linear relationship between time and distance when optimal route are chosen. More precisely, the average speed will be higher for longer trips when compared to shorter trips, showing that the street network makes driving further faster. We attribute this phenomenon to the spatial arrangement of extensive street segments that eliminate deceleration points. These results underscore the importance for cities to consider the distribution of deceleration-free streets while mitigating any negative impact on sustainability. To ensure efficient transportation planning and engineering, innovative approaches are necessary to facilitate the flow of goods and services while adhering to sustainable mobility principles.

Large-scale physical experimental study on the evolution of 3D bedform by irregular waves

A large-scale physical experiment was conducted to analyze the morphological seabed evolution in a large-wave flume at the Tianjin Research Institute for Water and Transport Engineering. The morphologies of the bedforms, ranging from two to three dimensions, were analyzed as wave mobility (represented by ѱw) increased. The sand-ripple morphology underwent four stages: straight, staggered, lunate and flat. Furthermore, the three-dimensional (3D) features and flat patterns were enhanced with increasing ѱw. The seabed ripple was processed using a wavelet transform and filter method to eliminate the effects of noise and dunes. The ripple wavelength followed the gamma and lognormal distributions for irregular waves, whereas the distribution of ripple height transitioned from normal to exponential with increasing ѱw. Furthermore, to predict the ripple-geometry statistics more accurately, a modified predictor was developed based on the acquired large-scale experimental data. The findings of this study can aid the development of innovative methods for evaluating bedform morphologies and statistical parameters.

Temperature and Thickness Dependence of the Thermal Conductivity in 2D Ferromagnet Fe3GeTe2.

The emergence of symmetry-breaking orders such as ferromagnetism and the weak interlayer bonding in van der Waals materials offers a unique platform to engineer novel heterostructures and tune transport properties like thermal conductivity. Here, we report the experimental and theoretical study of the cross-plane thermal conductivity, κ⊥, of the van der Waals two-dimensional (2D) ferromagnet Fe3GeTe2. We observe an increase in κ⊥ with thickness, indicating a diffusive transport regime with ballistic contributions. These results are supported by the theoretical analyses of the accumulated thermal conductivity, which show an important contribution of phonons with mean free paths between 10 and 200 nm. Moreover, our experiments show a reduction of κ⊥ in the low-temperature ferromagnetic phase occurring at the magnetic transition. The calculations show that this reduction in κ⊥ is associated with a decrease in the group velocities of the acoustic phonons and an increase in the phonon-phonon scattering of the Raman modes that couple to the magnetic phase. These results demonstrate the potential of van der Waals ferromagnets for thermal transport engineering.

Engineering Escherichia coli for Isobutanol Production from Xylose or Glucose-Xylose Mixture.

Aiming to overcome the depletion of fossil fuels and serious environmental pollution, biofuels such as isobutanol have garnered increased attention. Among different synthesis methods, the microbial fermentation of isobutanol from raw substrate is a promising strategy due to its low cost and environmentally friendly and optically pure products. As an important component of lignocellulosics and the second most common sugar in nature, xylose has become a promising renewable resource for microbial production. However, bottlenecks in xylose utilization limit its wide application as substrates. In this work, an isobutanol synthetic pathway from xylose was first constructed in E. coli MG1655 through the combination of the Ehrlich and Dahms pathways. The engineering of xylose transport and electron transport chain complexes further improved xylose assimilation and isobutanol production. By optimizing xylose supplement concentration, the recombinant E. coli strain BWL4 could produce 485.35 mg/L isobutanol from 20 g/L of xylose. To our knowledge, this is the first report related to isobutanol production using xylose as a sole carbon source in E. coli. Additionally, a glucose-xylose mixture was utilized as the carbon source. The Entner-Doudorof pathway was used to assimilate glucose, and the Ehrlich pathway was applied for isobutanol production. After carefully engineering the recombinant E. coli, strain BWL9 could produce 528.72 mg/L isobutanol from a mixture of 20 g/L glucose and 10 g/L xylose. The engineering strategies applied in this work provide a useful reference for the microbial production of isobutanol from xylose or glucose-xylose mixture.

Efficient biosynthesis of 3-hydroxypropionic acid from glucose through multidimensional engineering of Escherichia coli

3-Hydroxypropionic acid (3-HP) is a top value-added chemical with multifaceted application in chemical, material, and food field. However, limited availability of robust strains and elevated fermentation costs currently impose constraints on sustainable biosynthesis of 3-HP. Herein, transporter engineering, metabolic dynamic modulation, and enzyme engineering were combined to address above limitations. First, a glucose-utilizing 3-HP biosynthetic pathway was constructed in Escherichia coli, followed by recruiting alternative glucose transport system to overcome center metabolism overflow. Next, the Cra (a transcription factor)-dependent switch was applied to autonomously fine-tune carbon flux, which alleviated growth retardation and improved the 3-HP production. Subsequently, inactivation of glycerol facilitator (GlpF) increased intracellular glycerol levels and boosted 3-HP biosynthesis, but caused toxic intermediate 3-hydroxypropionaldehyde (3-HPA) accumulation. Furthermore, semi-rational design of aldehyde dehydrogenase (YdcW) increased its activity and eliminated 3-HPA accumulation. Finally, fed-batch fermentation of the final strain resulted in 52.73 g/L 3-HP, with a yield of 0.59 mol/mol glucose.

PM10 emissions from tires: A disruptive estimate questioning present pollution mitigation strategies

Emissions from automotive internal combustion engines in the form of exhaust gases from the combustion of gasoline, diesel, liquefied petroleum gas or natural gas are widely recognized to represent the primary source of atmospheric PM10 pollution. Technological progresses in the design and manufacturing of road transport engines is progressively focusing toward both increasing their performance and energy efficiency and reducing their environmental impact.PM10 production from tires has significantly increased in the last ten years. The present study aims at assessing the contribution to atmospheric PM10 pollution from tires and its overall environmental impact. More specifically, we aim at estimating this contribution in the top 10 populated cities in Italy. The research focuses on the years 2018 and 2020. Results indicate that atmospheric PM contribution from tires is larger than the contribution from exhausted gases (for example, 12.5 times larger in Bologna in 2018, 13.9 in Firenze in 2020, 11.8 in Torino in 2020) and that cities where tires' PM10 concentrations are larger than those from exhaust gas passed from 4 in 2018 to 6 in 2020. This implies the need to define specific mitigation strategies aimed at reducing PM10 emissions from tires, pushing toward the production of lighter vehicles, the use of narrower wheels and the promotion of public transport on rail and micro-mobility devices. The verification of results is based on the comparison between the total amount of PM10 particles emitted by vehicles’ tire, normalized by the surface of each municipality, and the measured PM10 mean annual concentrations.

Evaluation on the application mode of blockchain technology in water transportation engineering project management

Abstract Due to the continuous development and application of blockchain technology, more and more industries are exploring its application in project management. In the management of water transportation engineering projects, blockchain technology also has certain application potential. This article will start with the characteristics of blockchain technology, and the current situation and needs of water transportation project management, analyze the application mode of blockchain technology in water transportation project management, and explore its advantages, limitations, and practical applications. The experimental results of this article showed that when blockchain technology was applied to the management of water transportation engineering projects, its information sharing score was 93; its data storage and management score was 96.1; its smart contract score was 97.4; its fund management score was 97.1; its Internet of Things technology score was 96.5, which was far higher than the score of applying traditional technologies. It was shown that using blockchain technology for water transportation engineering project management can improve the efficiency and quality of project management, reduce costs, and extend to a wider range of water transportation lines and project fields in the future.

Physicochemical test of leucaena leucocephala pellets using various types of adhesives

Forage availability is a problem in developing sustainable livestock farming for ruminants in Indonesia. The availability of forage is influenced by several factors, one of which is the availability of land for fodder crop cultivation. The study aimed to test the physicochemistry of Leucaena leucocephala pellets using various types of adhesives originating from local raw materials in the form of tapioca flour, corn flour, sago flour, and commercial adhesives which were carried out for 1 month, namely August 2022 at the Animal Feed Analysis Unit Laboratory, Unit Laboratory Feed Manufacturing, and Transportation Engineering System Laboratory, Halu Oleo University. The results of the study showed that the use of various types of adhesives on the physical and chemical qualities of Leucaena leucocephala forage pellets had a significant effect on the value of pellet durability index, specific gravity, crude protein, dry matter, and organic matter. In contrast, the density value did not show a significant effect. The best results were found using a 3% sago flour adhesive with a Pellet durability index value of 86.71% and a specific gravity of 1.27 g/ml. The adhesive that can improve the chemical quality of Leucaena leucocephala pellets uses 3% corn flour adhesive, which produces a crude protein content of 24.92%. The highest dry material and organic ingredients values are obtained using 3% Tapioca flour adhesive with values of 95.73% and 88.04%.

An investigation of combined effects of road capacity and accessibility on urban density, land use mix, and vitality

This study examines the combined impact of road accessibility and road capacity on urban form characteristics such as land use mix, building density, and vitality. The investigation was conducted in three cities in Sri Lanka: Colombo, Kurunegala, and Mawanalla. The study recognises the fundamental role of accessibility in shaping land use mix and urban densities and acknowledges the reciprocal relationship between transport infrastructure and land use decisions. It also recognises that the capacity of road infrastructure can influence land use choices and development patterns. Accessibility, in this context, can be thought of as the degree to which different parts of the city are well-connected and easily reachable. It includes not only the presence of roads but also their connectivity. By investigating how variations in accessibility and road capacity affect land use mix, densities, and vitality within the study areas, the study aims to discern the intricate relationships between transportation networks, land use, and density decisions. This study finds that accessibility has a stronger influence on density, land use mix, and vitality than road capacity. Further, the study finds that the influence of vehicle movement on land use mix, density, and vitality indicated a strong relationship, while the influence of pedestrian movement indicated a weak relationship. Accordingly, the findings of this study have practical implications for both transport and urban planning professionals and academics. Transport engineers can help promote desirable urban form characteristics by improving the accessibility of the road network. Urban planners can consider key findings when making zoning plans and urban development plans.

Vibrations control of railway vehicles using decentralized proportional integral derivative controller with flow direction optimization algorithm

The reduction of vibration-induced discomfort in vehicles is an important goal in the field of transportation engineering. Several mathematical models with various controlling techniques, from classical to modern, have been employed to achieve better ride comfort. Still, no comprehensive solution has yet been found. Therefore, this paper proposes a 17-degree-of-freedom (minimum number of coordinates) dynamic model of a full-scale railway vehicle integrated with wheel-rail contact forces and an active suspension system. Two controllers, termed system and force tracking controllers, suppress the vehicle body's vibrations. Based on a multi-loop control structure, three optimally tuned Proportional Integral Derivative controllers evaluate the desired control forces and performs the system controller’s action. While the force-tracking controller generates the command voltage to track that forces. The parameters of controllers are tuned with a novel metaheuristic optimization algorithm known as the flow direction algorithm (FDA), and the results are compared with two other optimization techniques, i.e., particle swarm optimization and ant colony optimization. The simulated results show that the ride comfort of the vehicle is improved with FDA, as the root mean square values of the lateral, roll, and yaw accelerations are reduced by 42.01%, 33.12%, and 48.24%, respectively. Moreover, the simulated results of the proposed model are validated with the experimental results of accelerations. The simulated results show that the proposed system tuned with the metaheuristic algorithm outperforms with a significant reduction in vehicle vibrations.