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New transition curves from straight paths to circular paths are proposed for the first time in this study. The paths enable the vehicles to maintain constant normal acceleration components when the vehicle has a given tangential deceleration component. The differential equation describing the path for an arbitrary tangential deceleration component is given first. Several special cases corresponding to different deceleration functions in terms of velocity and position are derived. The path equations are third order ordinary differential equations with high nonlinearities. The equations are cast into a non-dimensional form which enables to define the dimensionless parameters affecting the curves. Two of the special cases are numerically treated: (1) Deceleration proportional to the velocity, (2) Deceleration exponentially decaying with path length. The effects of dimensionless parameters on the solutions are exploited in the figures. The transition curves may be employed in determining the paths of land, aerial and marine vehicles. [ABSTRACT FROM AUTHOR]

Real-time Kinematic (RTK) positioning provides centimeter-level positioning accuracy within several seconds, but it has to rely on a nearby base station. Although Precise Point Positioning (PPP) supplies precise positions with one receiver, its convergence time takes several tens of minutes, which makes PPP not well suited for real-time kinematic applications where a rapid convergence is required. PPP-RTK integrates the benefits of PPP and RTK, which actually is PPP augmented by a ground GNSS network. The satellite orbit, clock offsets, signal biases, ionospheric and tropospheric corrections are determined based on this GNSS network, modeled as state space information and transmitted to PPP users. By applying these State Space Representation (SSR) corrections, a real-time kinematic PPP-RTK approach is developed and implemented, which can instantly resolve the ambiguities to integers and realize rapid convergence. In a static scenario, it realized an instant ambiguity resolution and a rapid convergence within 2 s in more than 90% of 120 hourly sessions. The PPP-RTK has been applied and evaluated in a kinematic scenario on the highway. The horizontal positioning errors are almost lower than 0.1 m except for the time of passing through bridges. After passing bridges, the PPP-RTK successfully resolved ambiguities within 2 s in 90.6% of the cases and achieved convergence in horizontal within 5 s in more than 90% of the cases. The PPP-RTK with a precision of 0.1 m and rapid convergence of several seconds benefits the precise navigation of automobile on the highway, which will support the development of autonomous driving in future. [ABSTRACT FROM AUTHOR]

Presently, most smart cities face massive traffic issues every day. The smart cities' significant challenge is the traffic control system, wherein some places are automated and cost-effective. In this manuscript, cloud-assisted Internet of things Intelligent Transportation System (CIoT-ITS) is proposed to overcome traffic management's challenges. Here, the IoT sensor integrated camera is installed in every traffic signal corner to monitor the vehicle's flow. Further, the optimised vehicle flow data is sent to the cloud processes. The data from the various signal corners runs an algorithm to detect traffic direction and controls the signal lights. The alert notification is sent to the nearest traffic control room during traffic congestion using IoT sensors. Simulation analysis proved that the proposed CIoT-ITS could monitor and manage the vehicle flow successfully and automatically. The proposed system has been validated based on the optimisation parameter, which outperforms conventional methods. [ABSTRACT FROM AUTHOR]

Real-time Kinematic (RTK) positioning provides centimeter-level positioning accuracy within several seconds, but it has to rely on a nearby base station. Although Precise Point Positioning (PPP) supplies precise positions with one receiver, its convergence time takes several tens of minutes, which makes PPP not well suited for real-time kinematic applications where a rapid convergence is required. PPP-RTK integrates the benefits of PPP and RTK, which actually is PPP augmented by a ground GNSS network. The satellite orbit, clock offsets, signal biases, ionospheric and tropospheric corrections are determined based on this GNSS network, modeled as state space information and transmitted to PPP users. By applying these State Space Representation (SSR) corrections, a real-time kinematic PPP-RTK approach is developed and implemented, which can instantly resolve the ambiguities to integers and realize rapid convergence. In a static scenario, it realized an instant ambiguity resolution and a rapid convergence within 2 s in more than 90% of 120 hourly sessions. The PPP-RTK has been applied and evaluated in a kinematic scenario on the highway. The horizontal positioning errors are almost lower than 0.1 m except for the time of passing through bridges. After passing bridges, the PPP-RTK successfully resolved ambiguities within 2 s in 90.6% of the cases and achieved convergence in horizontal within 5 s in more than 90% of the cases. The PPP-RTK with a precision of 0.1 m and rapid convergence of several seconds benefits the precise navigation of automobile on the highway, which will support the development of autonomous driving in future.

Therapeutic monoclonal antibody (mAb) products for intravenous (IV) administration generally require aseptic compounding with a commercially available diluent. When the administration site is located away from the preparation site, the prepared dosing solution may need to be transported in a vehicle. The impact of vehicle transportation on the product quality of mAbs needs to be evaluated to define safe handling and transportation conditions for dosing solutions. The design and execution of actual vehicle transportation studies require considerable resources and time. In this study, we systematically developed three different laboratory equipment-based methods that simulate vehicle transportation stresses: orbital shaker (OS), reciprocating shaker (RS), and vibration test system (VTS)-based simulation methods. We assessed their feasibility by comparing the impact on product quality caused by each simulated method with that caused by actual vehicle transportation. Without residual polysorbate 80 (PS80) in the mAb dosing solution, transportation via a cargo van led to a considerable increase in the subvisible particle counts and did not meet the compendial specifications for the light obscuration method. However, the presence of as low as 0.0004%w/v (4 ppm) PS80 in the dosing solution stabilized the mAb against vehicle transportation stresses and met the compendial specifications. Vehicle transportation of an IV bag with headspace resulted in negligible micro air bubbles and foaming in both PS80-free and PS80-containing mAb dosing solutions. These phenomena were found to be comparable to the VTS-based simulated method. However, the OS- and RS-based simulated methods formed significantly more micro air bubbles and foaming in an IV bag with headspace than either actual vehicle transportation or the VTS-based simulated method. Despite the higher interfacial stress (micro air bubbles and foaming) in the dosing solution created by the OS- and RS-based simulated methods, 0.0004%w/v (4 ppm) PS80 in the dosing solution was found to be sufficient to stabilize the mAb. The study shows that under appropriate simulated conditions, the OS-, RS-, and VTS-based simulated methods can be used as practical and meaningful models to assess the impact and risk of vehicle transportation on the quality of mAb dosing solutions.

According to the Central Statistical Office in Poland, for the last 10 years (2009 - 2018), the number of trucks has increased by as much as 25%. More than 6 million trucks drive in the European Union, and Poland, followed by Italy, boasts of the largest fleet (over one million trucks) . For some time, freight transportation companies have been signaling the problem of lack of staff. The Polish Road Transport Inspectorate and the National Labor Inspectorate supervise the transportation sector. All issues related to drivers’ working time are law-regulated. The main objective of introducing regulations on drivers’ working time is to improve road safety and drivers’ working conditions. The top-down imposition of break and rest periods prevents drivers’ fatigue and serves to regenerate forces. Fatigue reduces psychomotor skills, and the speed of reaction is particularly important in this profession. The practical goal of this article is to show how drivers perceive these problems, this scientific problem but in a different approach was also presented in the works. The analyzed results come from research conducted by the authors of the article. The research was conducted in the form of a multidirectional survey, 100 people (professional trucks drivers) answered each question. Each of them declared that they are a driver and work in Poland. The study was conducted in December 2018.

Greenhouse gas (GHG) concentration in the atmosphere has increased since the beginning of the industrial era, with dramatic effects on climate change. Transportation is one of the main sources of GHGs, with more than two-thirds of transport-related GHG emissions attributable to road vehicles. Any policy that aims to reduce GHG emissions needs robust measuring methods that guarantee the quality and reliability of primary data and estimates. However, these estimates are subject to uncertainty, both at the stage of compiling accounting tables and at the stage of using this information to formulate a specific policy question. This paper considers how to reduce uncertainty in estimating GHG emissions from road transportation, with specific reference to a regional emissions inventory in Italy. We propose the application of a use-chain model that can tackle uncertainty in measuring GHG emissions by enhancing the quality of the emissions data registry in the inventory. This new metric, which we call emission value at risk (VaR), draws from methodologies and concepts employed in the insurance and financial sectors. Moreover, additional assessments are performed, integrating the inventory data with those available in the regional energy balance and disaggregated sectoral economic dataset. The results show that a sound accounting method enables uncertainty in emission data to be taken into account, thus improving the design of appropriate strategies to reduce GHG emissions. [ABSTRACT FROM AUTHOR]

In view of problems of low efficiency, serious dust pollution and needing large place of manual loading method, the paper proposed a technology of intelligent vehicle loading, and described technological process, determination of main technical parameters, realization of weighing and intelligent batching technology of intelligent vehicle loading system using the proposed technology in details.The intelligent vehicle loading technology achieves fast, accurate, uniform and flat auto-loading, can prevent material loss and environmental pollution during transportation, and ensure transport safety.

In this study, HMs concentration in sediments and water from the Lake Pontchartrain estuary along the I-10 Bridge were investigated in two seasons to evaluate the level of contamination and to assess the effect of vehicular traffic. Vehicular traffic has led to HMs such as As, Cd, Cr, Pb, Zn, Ni, and Cu accumulation in sediments along the bridge. The HMs content in water especially in summer increased due to high temperature which led to release of HMs from the sediments. The level of pollution attributed to anthropogenic activities was evaluated using several pollution indicators. The overall HMs bioavailability and EFs was mostly high in summer and the concentration of the HMs in both sediments and water was highly influenced by the season and the distance from the highways. The content of As and Cd in lake sediments were higher than the background values (BGV) for both seasons (spring and summer), and Cr and Pb in sediments were higher than the BGV in most sampling points in the spring. According to Sediments Quality Guidelines (SQGs), heavy metals except for As have low biotoxicity, and As could potentially result in harmful effects on the aquatic organisms. The relationship between As and vehicular traffic is less studied so our finding stress the need for further study on source of As in Lake Pontchartrain sediments. [ABSTRACT FROM AUTHOR]

In this study, a genetic algorithm is applied to obtain the best combination of transportation parameters for vehicle dispatching. The searching mechanism based on genetic algorithm can find several feasible solutions of dispatching parameters to proceed with transportation plan within constrained conditions. Besides, the concept of fuzzy due time is applied to replace that of time window so as to meet customers' preferences and demands much better. A fuzzy vehicle routing and scheduling problem (FVRSP) is formulated with five attributes: space utility, service satisfaction, waiting time, delay time, and transportation distance and proposed to solve it with a pure genetic algorithm method. In addition, the system can simultaneously calculate the residual loading capacity of weight and volume of each vehicle in order to provide the dispatcher with options to tune the dispatching operation. With the help of this system of acquiring the optimal solution to vehicle transportation, the promotion of the efficiency of transportation can thus be achieved. [ABSTRACT FROM AUTHOR]