Lakshmi Shankar Iyer
Hasil untuk "Transportation engineering"
Menampilkan 20 dari ~9498771 hasil · dari CrossRef, DOAJ, Semantic Scholar
Mondira Chakraborty, Sajeeb Saha, Selina Sharmin
Somporn Sahachaiseree, Takashi Oguchi
ABSTRACT Reinforcement learning (RL) is a promising machine‐learning solution to traffic signal control problems, which have been extensively studied. However, variants of non‐linear, deep artificial neural network (ANN) function approximators (FAs) have been predominantly employed in previous studies proposing RL‐based controllers, leaving a significant interpretability issue due to their black‐box nature. In this work, the use of the linear FA for a value‐based RL agent in traffic signal control problems is investigated along with the least‐squares Q‐learning method, abbreviated as LSTDQ. The interpretable linear FA was found to be adequate for the RL agent to learn an optimal policy. This leads to the proposal to replace a non‐linear ANN FA with the linear FA counterpart, resolving the interpretability issue. Moreover, the LSTDQ learning method shows superior behaviour convergence compared to a gradient descent method. In a low‐intensity arrival pattern scenario, the control by the RL agent cuts about half of the average delay resulting from the pretimed control. Owing to the conciseness of the linear FA, a direct interpretation analysis of the converged linear‐FA parameters is presented. Lastly, two online relearning tests of the agents under non‐stationary arrivals are conducted to demonstrate the online performance of LSTDQ. In conclusion, the linear‐FA specification and the LSTDQ method are together proposed to be used for its control algorithm interpretability property, superior convergence quality, and lack of hyperparameters.
Boniphace Kutela, Frank Ngeni, Cuthbert Ruseruka et al.
Over-speeding is a pivotal factor in fatal traffic crashes globally, necessitating robust speed management strategies to augment road safety. In 2021, the National Highway Traffic Safety Administration reported over 12 000 speed-related fatalities in the United States alone. Previous studies aggregated over-speeding tendencies; however, the extent of over-speeding has a significant implication on the crash outcome. This study delves into the prevalence and magnitude of over-speeding in various scenarios, utilizing data from traffic cameras in Edmonton, Canada, and employing a negative binomial statistical model for analysis. The model elucidates the significance and likelihood of over-speeding tendencies by incorporating temporal and built environment variables, i.e., year, month, number of lanes, dwelling unit types, school-related, and open green space. Study results indicated that the aggregation of the over-speeding data tends to underestimate the influence of various factors. Notably, the estimated impact of the posted speed limit for the disaggregated models is up to over two times that for the aggregated model. Further, the summer months exhibit a roughly 25% uptick in speed limit violations for aggregated models while about a 40% uptick in the speed limit violations for disaggregated approaches. Conversely, a discernible decline in over-speeding tendencies is observed with camera enforcement, showcasing a 25% reduction over four years. Built environment variables presented mixed results, with one-unit dwellings associated with a 12% increase in over-speeding, while proximity to schools indicated a 10% decrease. These pivotal findings provide policymakers and practitioners with valuable insights to formulate targeted interventions and countermeasures to curtail speed limit violations and bolster overall road safety conditions.
Junchao Yang, Ziyang Peng
Countries worldwide are increasingly focused on addressing the imbalance between the supply and demand for EV charging infrastructure, with the community-shared charging post (CSCP) co-construction project emerging as a promising solution. The broad participation and investment support of the residents are the keys to the success of the CSCP co-construction project. This study, grounded in the theory of planned behavior (TPB) from social psychology, incorporated factors such as community identity, perceived green value, economic benefit, uncivil behaviors, and perceived risk to construct a structural model explaining community residents’ intention to invest in the CSCP co-construction project. This research confirmed that (1) 85.73% of respondents expressed strong recognition of the CSCP co-construction project, with a mean recognition score of 5.56 out of a possible 7; (2) an individual’s social-related perceptions, including the subjective norms and community identity are the strongest determinant of the intention to invest in the CSCP co-construction project; (3) the willingness to invest in CSCP co-construction project differs significantly between the EV group and the non-EV group. Economic benefit was significant only for the non-EV group, while uncivil behaviors were significant only for the EV group. These results provide valuable guidelines for governments and corporations that are promoting or pursuing sharing community for the residents.
Siyu Teng, Xuan Li, Yuchen Li et al.
In recent years, open-pit mining has seen significant advancement, the cooperative operation of various specialized machinery substantially enhancing the efficiency of mineral extraction. However, the harsh environment and complex conditions in open-pit mines present substantial challenges for the implementation of autonomous transportation systems. This research introduces a novel paradigm that integrates Scenario Engineering (SE) with autonomous transportation systems to significantly improve the trustworthiness, robustness, and efficiency in open-pit mines by incorporating the four key components of SE, including Scenario Feature Extractor, Intelligence and Index, Calibration and Certification, and Verification and Validation. This paradigm has been validated in two famous open-pit mines, the experiment results demonstrate marked improvements in robustness, trustworthiness, and efficiency. By enhancing the capacity, scalability, and diversity of autonomous transportation, this paradigm fosters the integration of SE and parallel driving and finally propels the achievement of the ‘6S’ objectives.
U. Syed, Ethan Light, Xing-ming Guo et al.
In this paper, we explore the capabilities of state-of-the-art large language models (LLMs) such as GPT-4, GPT-4o, Claude 3.5 Sonnet, Claude 3 Opus, Gemini 1.5 Pro, Llama 3, and Llama 3.1 in solving some selected undergraduate-level transportation engineering problems. We introduce TransportBench, a benchmark dataset that includes a sample of transportation engineering problems on a wide range of subjects in the context of planning, design, management, and control of transportation systems. This dataset is used by human experts to evaluate the capabilities of various commercial and open-sourced LLMs, especially their accuracy, consistency, and reasoning behaviors, in solving transportation engineering problems. Our comprehensive analysis uncovers the unique strengths and limitations of each LLM, e.g. our analysis shows the impressive accuracy and some unexpected inconsistent behaviors of Claude 3.5 Sonnet in solving TransportBench problems. Our study marks a thrilling first step toward harnessing artificial general intelligence for complex transportation challenges.
Yimeng Zuo, Minghui Zhao, Yuanwei Gou et al.
Plant natural products (PNPs) exhibit a wide range of biological activities and have essential applications in various fields such as medicine, agriculture, and flavors. Given their natural limitations, the production of high-value PNPs using microbial cell factories has become an effective alternative in recent years. However, host metabolic burden caused by its massive accumulation has become one of the main challenges for efficient PNP production. Therefore, it is necessary to strengthen the transmembrane transport process of PNPs. This review introduces the discovery and mining of PNP transporters to directly mediate PNP transmembrane transportation both intracellularly and extracellularly. In addition to transporter engineering, this review also summarizes several auxiliary strategies (such as small molecules, environmental changes, and vesicles assisted transport) for strengthening PNP transportation. Finally, this review is concluded with the applications and future perspectives of transportation engineering in the construction and optimization of PNP microbial cell factories.
Apostolos Anagnostopoulos
Jian Liu, Fangyu Liu, Linbing Wang
The increasing impact of the greenhouse effect on ecosystems is prompting transportation agencies to seek methods for reducing CO2 emissions during pavement construction and maintenance. Additionally, the laboratory mix design process, which involves selecting aggregate gradation and binder content, is time-consuming and labor-intensive. To accelerate the traditional mix design procedure, this study presented a mix design procedure that can automatically determine gradation and binder content based on machine learning (ML) and a meta-heuristic algorithm. Specifically, ML approaches were employed to model the relationship between volumetric properties (mixture bulk specific gravity (Gmb) and air void (VV)) and both mixture component properties and mixture proportion, based on a dataset collected from literature with 660 mixture designs. Integrated with the prediction of ML models and the modified multi-objective grey wolf optimization (MOGWO) algorithm, an automatic asphalt mix design was proposed to pursue three goals, including VV, cost, and CO2 emission. The results indicated that least squares support vector regression (LSSVR) and eXtreme gradient boosting (XGBoost) achieved the highest prediction accuracies (correlation coefficient: 0.92 for VV and 0.96 for Gmb). The MOGWO algorithm successfully found the 26 optimal mix designs for the case of VV vs. cost vs. CO2 emission. Compared to the traditional laboratory design, the optimal mixture with VV of 4% achieves a cost saving of 2.46% and a reduction of 4.03% in carbon emission. The volumetric properties of the mixtures output by the approach also align closely with values measured in a laboratory.
D. S. Spivak, S. V. Kliuchnyk
Purpose. The paper aims to highlight and substantiate the need to find rational design schemes for lattice tube concrete bridges with a ride on top based on the analysis of recent research and regulatory documents. Methodology. The current scientific research is analyzed to determine the current state of development of pipe concrete lattice structures. Methods for improving structures are presented. Combinations of filling the grating elements with concrete, variants of cross-sections of the grating elements, their advantages and disadvantages are analyzed. The state of building codes of Ukraine and other countries is considered in order to determine possible options for the design of pipe concrete bridge structures. Due to the lack of detailed research on this issue, the feasibility of implementing optimization studies for these structures and the steps necessary for this are determined. Findings. The optimization of pipe-concrete bridge structures is a relevant area of research, but it requires a multicomponent approach and the use of modern computer facilities. The method of linear optimization is proposed and its general steps for finding economic models are determined. It was found that the base of Ukrainian SCSs in the field of pipe and concrete structures is limited, but can be expanded by using European standards and other international regulations. Originality. The necessity of global development and improvement of pipe concrete gratings of bridge spans is highlighted. Attention is focused on the advantages of this area, which contributes to decision-making at the stage of selecting the type of bridge and detailed design of pipe-concrete lattice bridges. A methodology for finding the optimal grids is proposed, which can integrate existing methods of structural improvement and the requirements of regulatory documents. Practical value. The results of the study can be used to improve the design of pipe concrete bridges at the design stage. Optimization of gratings can help to increase the efficiency of construction and reliability of this type of bridge structure.
Ziyi Yin, Guowei Huang, Rui Zhao et al.
Abstract Crowdfunding has become important in increasing financial support for the development of green technologies. Self-disclosed information significantly affects supporters’ decisions and is important for the success of green project funding. However, current studies still lack investigations into the impact of information disclosure on green crowdfunding performance. This research aims to fill this knowledge gap by exploring eight information disclosure-relevant factors in green crowdfunding performance. Applying machine learning techniques (e.g., Natural Language Processing and Computer Vision) and logistic regression, this study investigates 720 green crowdfunding campaigns on GoFundMe and empirically finds that the duration, length of campaign introductions, and length of the title influence fundraising outcomes. However, no evidence supports the impact of goal size, emotion of campaign introduction, or image content on funding success. This study clarifies the information disclosure-related data that green crowdfunding campaigns should consider and provides founders with a constructive guide to smoothly raise money for a green crowdfunding campaign. This study also contributes to data processing methods by providing future studies with an approach for transferring unstructured data to structured data.
Ali Matin Nazar, Y. Narazaki, Arash Rayegani et al.
Zahra Karami, Rasha Kashef
Liyu Lu
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.
Junjie Wang, Jianhe Xie, Yongliang Liu
The current Special Issue entitled "Sustainable Cementitious Materials for Civil and Transportation Engineering" aims to discuss current research on the preparation, characterization, and application of sustainable cementitious materials for civil and transportation engineering, with a special focus on the development of low-carbon construction materials [...].
Jan-Peter Glock, Julia Gerlach
Abstract Cars are dominating urban traffic in cities around the world, even though daily trips in many cities are often realized with active modes of transportation or public transport. Urban transport planning processes need to adapt to this reality and the necessity of climate change mitigation. Against this background, the research project “Mobility Reporting”, a joint undertaking of the district Pankow in Berlin and researchers from TU Berlin and TU Dresden, established a new, goal-driven, and participative planning process. The process identified local mobility as one of the central planning goals. The 15-min city (FMC) was thus adduced as a benchmark to analyze the district’s current mobility system and development potential. We conducted extensive accessibility analyses to examine the status quo concerning the FMC. We calculated travel times to essential destinations in daily life by foot, public transport, and car. This analysis was accompanied by a mixed online and paper–pencil survey conducted to evaluate the perceived accessibility of people in Pankow. The survey results shed light on the question of which walking time thresholds constitute a “very good” or “good” accessibility. Further analyses included environmental and social variables, allowing us to check whether areas with different accessibility levels also differ regarding the socio-economic characteristics of their inhabitants. For example, do socially advantaged neighborhoods have better local accessibility? Is there a trade-off between exposure to environmental pollution and good accessibility? With this contribution, we shed light on what an FMC is and ought to be. Results from the survey support the normative and political vision of the FMC. Pankow generally offers the merits of a walkable city, showing the expected travel time differences between the dense inner city and the outskirts. Socially disadvantaged neighborhoods are not consistently less accessible. However, there seems to be a trade-off between good accessibility (especially PT accessibility) and correlated externalities of transport, namely air pollution and noise.
Dapai Shi, Jingyuan Zhao, Chika Eze et al.
As the popularity of electric vehicles (EVs) and smart grids continues to rise, so does the demand for batteries. Within the landscape of battery-powered energy storage systems, the battery management system (BMS) is crucial. It provides key functions such as battery state estimation (including state of charge, state of health, battery safety, and thermal management) as well as cell balancing. Its primary role is to ensure safe battery operation. However, due to the limited memory and computational capacity of onboard chips, achieving this goal is challenging, as both theory and practical evidence suggest. Given the immense amount of battery data produced over its operational life, the scientific community is increasingly turning to cloud computing for data storage and analysis. This cloud-based digital solution presents a more flexible and efficient alternative to traditional methods that often require significant hardware investments. The integration of machine learning is becoming an essential tool for extracting patterns and insights from vast amounts of observational data. As a result, the future points towards the development of a cloud-based artificial intelligence (AI)-enhanced BMS. This will notably improve the predictive and modeling capacity for long-range connections across various timescales, by combining the strength of physical process models with the versatility of machine learning techniques.
Bumin Meng, Zhengzhao Zhou, Congyue Zhang et al.
ABSTRACT: The brake-by-wire (BBW) system is an essential part of the intelligent electric vehicle, which is determination of the braking safety and recovery efficiency. To design a safe and efficient booster motor, the design of booster motor for BBW system is discussed in this paper. Through comparative analysis, experimental simulation and assessment argument, the scheme of designing a booster motor for brake-by-wire system is completely described. First, the mainstream structure of the BBW system and the main challenges it faces in the assisted motor are discussed. Second, comparing the motors of different types and structures, the motor body and control system scheme suitable for the characteristics of the booster motor system are determined. Then, through the simulation analysis of the ansoft and matlab, the optimization scheme of the motor and performance improvement are proposed. Further, through the actual design of a set of the booster motor system, the safe and efficient motor designing are verified, and the problems involving functional safety are discussed. Finally, focus on the problem while simulation and experiment, some important countermeasures to improve current technology and prospect of in-depth study are pointed out.
Halaman 1 dari 474939