544 results match your criteria: "College of Transportation[Affiliation]"

The skeleton dense graded cement-stabilized crushed stone base is a widely used material for road construction. However, this material is susceptible to freeze-thaw damage, which can lead to degradation and failure, for which there is still a lack of an in-depth understanding of the freeze-thaw damage characteristics. This study aims to assess the mechanical performance and the freeze-thaw damage characteristics of the cement-stabilized crushed stone base with skeleton dense gradation based on a mechanical test and acoustic technology in a laboratory.

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The expansion of roads exacerbates the fragmentation of ecological networks and obstructs landscape connectivity. Scientific analysis of the impacts of different grades of roads on landscape connectivity and ecological networks is crucial for guiding road planning and ecological conservation. Based on the data of 2020 road network, land cover types, and digital elevation models, we used morphological spatial pattern analysis and circuit theory to construct ecological networks within different species dispersal distances (1, 3, 5, 10 km) in Fuzhou.

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Water resources variability and availability in a basin affect river flows and sustain river ecosystems. Climate change and human activities disrupt runoff sequences, causing water environmental issues like river channel interruptions. Therefore, determining ecological flow in changing environments is challenging in hydrological research.

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The monitoring requests on young driver's fatigue and take-over performance in prolonged conditional automated driving.

J Safety Res

February 2024

College of Civil Engineering, Inner Mongolia University of Science & Technology, Baotou 014010, China; Inner Mongolia Autonomous Region Civil Engineering Safety and Durability Key Laboratory, China; Inner Mongolia Autonomous Region Building Structure Disaster Prevention and Reduction Engineering Research Center, China.

Article Synopsis
  • - Automated vehicles can manage all driving tasks but may require human involvement during specific situations. This is particularly relevant for young drivers who may struggle with the transition, especially if they become fatigued or distracted.
  • - A study with 25 young drivers tested the impact of monitoring requests (MR) compared to just take-over requests (TOR) during automated driving, finding that the MR condition led to better reactions and overall performance during take-overs.
  • - The results suggest that MR can help alleviate fatigue and improve safety during automated driving, highlighting the importance of integrating such systems in vehicle design for better human-automation interaction.
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Faced with the contradiction between the increasing traffic volume and the aging road infrastructures in the rural area, this paper aims to propose feasible strategies to enhance the level of service and safety, by a case study of the rural area in the north Jintan district. In order to figure out current issues related to rural roads, a carefully designed investigation has been conducted, and the results of the two-week investigation include roads' basic information, traffic signs and protective facilities, surrounding landscape, and etc. Based on the field driving tests, specific problems including signs category, signs installation and facility maintenance have been fully analyzed.

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Chloride ion corrosion has been considered to be one of the main reasons for durability deterioration of reinforced concrete structures in marine or chlorine-containing deicing salt environments. This paper studies the relationship between the amount of fly ash and the durability of concrete, especially the resistance to chloride ion erosion. The heat trend map of total chloride ion factor correlation displayed that the ranking of factor correlations was as follows: sampling depth > cement dosage > fly ash dosage.

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Synthesis and Modification of Polycarboxylate Superplasticizers-A Review.

Materials (Basel)

February 2024

Huaihua Dongxing Concrete Co., Ltd., Huaihua 418000, China.

The molecular-scale structural changes in polycarboxylic superplasticizer (PCE) can influence dispersion and water retention. Polycarboxylate superplasticizer, synthesized using different methods, may alter dispersion and water-reducing effects. The synthesis of PCE involves creating a novel macromolecular monomer with a controllable molecular mass, adjustable lipophilic, and hydrophilic moieties, as outlined in this study.

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Concrete is a versatile material widely used in modern construction. However, concrete is also subject to freeze-thaw damage, which can significantly reduce its mechanical properties and lead to premature failure. Therefore, the objective of this study was to assess the laboratory performance and freeze-thaw damage characteristics of a common mix proportion of concrete based on compressive mechanical tests and acoustic technologies.

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Highways, as one of the main arteries of transit and transportation in today's world, play a fundamental role in accelerating transportation, and for this reason, continuous monitoring of them is of great importance. Among these, monitoring compliance with transportation laws by vehicles is of utmost importance; for automation, efficient and vehicle-specific models can be used. In this article, a new method for video surveillance of highways is presented using an extended Kalman filter (EKF) and reinforcement learning models.

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High-risk event prone driver identification considering driving behavior temporal covariate shift.

Accid Anal Prev

May 2024

College of Transportation Engineering, Tongji University, Shanghai, 201804, China; The Key Laboratory of Road and Traffic Engineering, Ministry of Education, 4800 Cao'an Road, 201804, Shanghai, China. Electronic address:

Drivers who perform frequent high-risk events (e.g., hard braking maneuvers) pose a significant threat to traffic safety.

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An improvement on the electrocatalytic performance of ZIF-67 byself-growing CNTs on surface.

Nanotechnology

March 2024

College of Transportation Engineering, Dalian Maritime University, Dalian 116026, People's Republic of China.

Efficient and robust oxygen reduction reaction (ORR) catalysts are essential for the development of high-performance anion-exchange membrane fuel cells (AEMFC). To enhance the electrochemical performance of metal-organic frameworks of cobalt-based zeolite imidazolium skeleton (ZIF-67), this study reported a novel ZIF-67-4@CNT bygrowing carbon nanotubes (CNTs) on the surface of ZIF-67 via a mild two-step pyrolysis/oxidation treatment. The electrochemical results showed that the as-prepared ZIF-67-4@CNT after CTAB modification exhibited excellent catalytic activity with good stability, with E, E, and I, respectively were 0.

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Navy escorts are considered crucial in countering illegal piracy attacks. In this paper, a novel approach is developed to investigate the effect of navy escorts on piracy incidents by models based on two enhanced Tree-Augmented Naïve (TAN) Bayesian networks. This approach offers a systematic investigation into the various factors that influence pirate activities, and helps to identify changes in piracy attack behaviors when confronted by navy escorts and assess the effectiveness of anti-piracy measures.

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Article Synopsis
  • Ionic liquids (ILs) are unique liquid salts known for their low melting points, ionic nature, and customizable properties, making them valuable in fluorescence sensing technologies.
  • This paper reviews various applications of ILs in fluorescence sensors, categorizing them based on the target materials like metals, explosives, and organic compounds.
  • The effectiveness of these sensors hinges on careful design to ensure they are specific and sensitive, with performance influenced by the chemical properties of the IL, the fluorophore used, and how they interact with the analyte being analyzed.
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Evaluation of the Thermal Stability and Micro-Modification Mechanism of SBR/PP-Modified Asphalt.

Polymers (Basel)

February 2024

Henan Key Laboratory of High-Grade Highway Detection and Maintenance Technology, Xinxiang 453003, China.

To evaluate the thermal stability of composite polymer-modified asphalt, thermoplastic elastomer styrene-butadiene rubber (SBR)/polypropylene (PP) pellets were prepared using a hot-melt blending technique, with butyl rubber powder and waste polypropylene pellets as raw materials. The effects of different evaluation indexes on the thermal stability of SBR/PP-modified asphalt were investigated using a frequency scan test and a multi-stress creep recovery (MSCR) test, and the compatibility of SBR/PP particles with asphalt was studied using the Cole-Cole diagram and microstructure images. The tests show that, firstly, the performance grade (PG) classification of asphalt can be improved by adding an SBR/PP thermoplastic elastomer to enhance the adaptability of asphalt in high- and low-temperature environments, and the evaluation separation index can reflect the high-temperature storage stability of composite-modified asphalt more reasonably.

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This research establishes an emergency evacuation time model specifically designed for subway stations with complex structures. The model takes into account multiple factors, including passenger flow rate, subway facility parameters, and crowd density, to accurately assess evacuation times. It considers the impact of horizontal walking distance, flow rate, subway train size, and stair parameters on the overall evacuation process.

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Food packaging detection devices have attracted attention to optimize storage situations and reduce food spoilage. However, low-cost and highly sensitive multifunctional sensors for detecting both food freshness and packaging pressure are still lacking. In this study, a multifunctional sensor was developed consisting of a MXene coated alcohol-soluble polyurethane fiber network (MXene/APU) and composite biohydrogel films made of konjac glucomannan, chitosan, and blueberry anthocyanin (KCB).

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Optimization of Forward Collision Warning Algorithm Considering Truck Driver Response Behavior Characteristics.

Accid Anal Prev

April 2024

College of Transportation Engineering, Tongji University, China; The Key Laboratory of Road and Traffic Engineering, Ministry of Education, Shanghai, China; National Engineering Laboratory for Integrated Optimization of Road Traffic and Safety Analysis Technologies, China. Electronic address:

Forward collision warning (FCW) systems have been widely used in trucks to alert drivers of potential road situations so they can reduce the risk of crashes. Research on FCW use shows, however, that there are differences in drivers' responses to FCW alerts under different scenarios. Existing FCW algorithms do not take differences in driver response behavior into account, with the consequence that the algorithms' minimum safe distance assessments that trigger the warnings are not always appropriate for every driver or situation.

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During a heavy traffic flow featuring a substantial number of vehicles, the data reflecting the strain response of asphalt pavement under the vehicle load exhibit notable fluctuations with abnormal values, which can be attributed to the complex operating environment. Thus, there is a need to create a real-time anomalous-data diagnosis system which could effectively extract dynamic strain features, such as peak values and peak separation from the large amount of data. This paper presents a dynamic response signal data analysis method that utilizes the DBSCAN clustering algorithm and the findpeaks function.

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Biomacromolecules have attracted interest as spraying additives due to their degradability, renewability, and non-toxicity. However, microscopic mechanism of the biomacromolecules regulating the droplet behavior on fruits and vegetables is still unclear. In this study, konjac glucomannan (KGM) was used to improve the spraying efficiency and the fresh-keeping performance of tea polyphenols solution.

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Foggy images affect image analysis and measurement because of their low definition and blurred details. Despite numerous studies on haze in natural images in hazy environments, the recovery effect is not ideal for processing hazy images in sky areas. A dark channel priori technique for processing haze images with sky areas where atmospheric light values are misestimated and halo artefacts are produced, as well as an improved dark channel priori single-image defogging technique based on image segmentation and joint filtering, are proposed.

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Comparison of the transportation network for public transit and private vehicles in Shanghai: An accessibility approach.

Heliyon

January 2024

Shenzhen Urban Transport Planning Center, 10th Floor, Block B, Building 9, Shenzhen Bay Technology Ecological Park, Nanshan District, Shenzhen, 518063, PR China.

This study examines the differences in service level and coverage of public transit (PT) and private vehicles (PV) with multi-source data in Shanghai. To construct computable networks and address visual results, the constrained shortest path algorithm and a spatial grid accessibility model are employed to seek the optimal path for travelers to city key points. Travel time ratio of PV and PT is applied to reflect the competitiveness of the two modes over different areas of Shanghai.

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Ultrasonic imaging of delamination in thick CFRP laminates using an energy-compensation reverse time migration method.

Ultrasonics

March 2024

State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment, School of Mechanics and Aerospace Engineering, Dalian University of Technology, Dalian 116024, China. Electronic address:

In ultrasonic reflection method, the precision of defect detection in thick carbon fiber reinforced plastics (CFRP) is compromised by acoustic energy attenuation. An energy-compensation reverse time migration (ECRTM) method is proposed to identify multiple defects accurately. Forward and backward wavefields are formed using the finite element method within an anisotropic acoustic model based on the Christoffel equation and Bond transformation.

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Article Synopsis
  • High aspect ratio microarray structures can enhance functions in areas like microfluidics and biomedicine by changing their shape or material properties in response to external stimuli.
  • Inspired by nature, research on microneedle functional surfaces shows that these structures can switch between hydrophilic and hydrophobic states, enabling tasks like liquid transport and drug delivery.
  • The review covers manufacturing techniques, mechanisms of liquid manipulation, intelligent control strategies, and highlights ongoing challenges and future possibilities in biomimetic surface applications.
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The leaping forward of the economy has promoted the rapid growth of road traffic demand, resulting in the carbon emissions of road traffic increasing significantly. It is well known that a one-size-fits-all emission reduction policy is not feasible. Therefore, conducting an investigation on the carbon emissions of all provincial-level regions within a country can assist the government in formulating carbon emission policies at a macro level tailored to different regions.

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Waterborne epoxy resin (WER), a cleaning material with exceptional high-temperature resistance, has attracted much attention to modify emulsified asphalt in the pavement material field. Epoxy value is the critical characteristic index of WER. In this research, three WER with the epoxy values of 0.

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