Massive Vehicles Research Articles

A Novel Efficient Hybrid Compensation Topology for Wireless Power Transfer

Wireless power transfer systems require compensators to improve efficiency by increasing transfer power between transmitter and receiver. The most commonly used compensators are series-series (SS), series–parallel, and double-sided LCC. This article analyzes the comparison between typical compensators focusing on transfer efficiency. Due to these characteristics of typical compensators, a hybrid compensation topology is designed based on two compensators. Hybrid compensation topology is capable of switching between SS and double-sided LCC topologies. Two ac switches are used on the transmitter and receiver for switching mode in hybrid compensation topology with wireless communication links, and its variation algorithm is clarified. A novel compensation topology guarantees system’s efficiency for a wide range of loads based on the maximum efficiency of two compensation topologies. The possibility of a proposed hybrid compensator is verified with an experimental prototype used for massive vehicles.

Reliable Uplink Synchronization Maintenance for Satellite-Ground Integrated Vehicular Networks: A High-Order Statistics-Based Timing Advance Update Approach

Satellite-ground integrated vehicular network can provision ubiquitous and unlimited network connectivity for massive vehicles, and is expected to play a vital role in 6G-supported intelligent transportation systems (ITS). However, due to its high-dynamic channel environments and limited satellite payload, the uplink synchronization has become a major bottleneck to restrict vehicular communication performance. Focusing on maintaining reliable uplink synchronization, we propose an efficient timing advance (TA) update approach in this paper. Specifically, an enhanced preamble format is first presented based on the periodical pairing sounding reference signals (SRSs), which enables the satellite to continuously track uplink timing variation with a low signaling overhead. By taking full advantage of all the fourth-order autocorrelation produces from the received preamble, we further design a novel timing metric consisted of the correlation and differential normalization functions, which is capable of having a considerably increased correlation length and shaper mainlobe, as compared to the existing ones. Through theoretical performance analysis, it is indicated that the proposed approach not only notably promotes class distance between the correct and wrong timing indexes, but also can achieve the immunity to multi-path effect and large carrier frequency offset (CFO), while having a reduced computational complexity. Simulation results in a typical low-earth-orbit (LEO) scenario reveal the superiority of our approach in terms of the false alarm probability, the missed detection probability, as well as the timing mean square error.

A Group-Based Multicast Service Authentication and Data Transmission Scheme for 5G-V2X

5G Vehicular to everything (5G-V2X) has grown more vigorously than ever before, and services massive vehicles can obtain provided by content providers via the network in all fields are widely acknowledged, such as listening to news channels and traffic channels. In the 5G-V2X network, content providers can provide service messages to a group of vehicles belonging to a specific area in point-to-multipoint transmission mode. However, various challenges are in front of the way when vehicles obtain multicast services due to the unique features of 5G-V2X, such as massive vehicles and strong mobility. In this paper, we present a typical vehicle multicast service model in 5G-V2X and propose a group-based multicast service authentication and data transmission scheme based on this model. In the scheme, massive vehicles within the same RAN coverage are constructed into a group and connected to the content provider to gain access to a multicast service using the distributed keys securely by the 5G home network. Subsequently, the multicast service key for protecting the multicast service data is distributed to each vehicle so that the multicast service data can be securely transmitted to vehicles in point-to-multipoint mode. The security analysis results using the formal verification tool and informal security analysis show that the proposed scheme supports the multicast services authentication and authorization, multicast service data protection, key distribution protection, anonymity, unlinkability, and protocol attack resistance. The performance analysis results regarding signaling, computational and communication overheads show that the proposed scheme outperforms other related schemes.

DRL-Based Low-Latency Content Delivery for 6G Massive Vehicular IoT

Vehicle-to-everything communication is an indispensable component of 6G networks that could help to facilitate future transportation systems. However, massive vehicles and unstable vehicle-to-vehicle (V2V) links may become bottlenecks for the low-latency delivery of contents, such as safety-critical emergency messages and multimedia. Instead of resolving the problem in a centralized way, we propose a massive vehicular Internet-of-Things system and investigate the approach that would enable each vehicle to decide the transmission mode from three modes, i.e., vehicle-to-network, vehicle-to-infrastructure and V2V sidelinks, and wireless resources. Specifically, a multiagent deep reinforcement learning (RL) framework is formulated by combining the multiagent RL approach, WoLF-PHC, with the techniques from deep <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$Q$ </tex-math></inline-formula> -learning (DQN) to gain the formulated framework with the capability of capturing the effects of interaction between learning agents and states of complex environment. The framework is set to maximize the throughput of vehicles while maintaining the latency and reliability constraints of the vehicle communication links. However, it could be easily extended to other objectives. The simulation results demonstrate that the proposed approach outperforms the compared ones in total traffic capacity and satisfaction rate of the vehicles in communication.

Dynamic Resource Orchestration for Service Capability Maximization in Fog-Enabled Connected Vehicle Networks

Technological advances in fog computing are precipitating an evolution in conventional vehicle networks to a new paradigm called fog-enabled connected vehicle networks (FCVNs). FCVNs provide communication efficiency for ensuring safe transportation through the massive Internet of vehicles. In FCVNs, massive vehicles tend to associate with roadside units and high power nodes, which act as fog nodes (FNs), when they have a good channel quality and/or popular contents. This circumstance may lead to a load imbalance among the FNs. This problem significantly decreases the resource utilization efficiency and service capability of the networks. In this article, we propose a dynamic resource orchestration (DRO) scheme to harmonize resource allocation for connected vehicles by migrating the offloaded services among FNs. A graph-theoretic approach is utilized to transform the FCVN into a directed graph model, where the maximum resource reduction obtained by service migrations is considered the weight of the link between every two FNs. Subsequently, the maximum weight matching solution is used to determine optimal pairs of FNs for migrating services to maximize network resource utilization. Our simulation results reveal that the proposed DRO scheme achieves significant improvements in terms of service capability, throughput, and resource utilization efficiency as compared with existing algorithms.

Analisa fatigue life konstruksi geladak pada kapal Landing Craft Tank menggunakan metode elemen hingga

The Landing Craft Tank ship is the usual vessels used to transport massive vehicles like excavator, bulldozer, heavy cargo and other heavy equipment indispensable for construction work. There are heavy equipment decks on the LCT vessels that are use to hold or support the cargo above it. The purpose of this study was to determine the stress value in the deck construction that has been modeled before with a plate thickness variation of 80%, 90% and 100% which is then followed by finding the value of fatigue life in the deck construction. The method used in the analysis this time is the finite element method which models the construction deck of LCT vessels assisted by finite element based applications. From the results of the study it was found that the stress on the deck construction of LCT vessels with plate thickness 100% was 99. 513 MPa, plate thickness 90% was 104. 72 MPa and at plate thickness 80% was 105. 19 MPa. While the value of fatigue life with a deck plate thickness of 100% is 26. 84 years with a number of cycles of 1006700 times, deck plate thickness of 90% is 16. 22 years with a number of cycles 129000 times and deck plate thickness of 80% is 15. 91 years with a number of cycles 125000. Keywords : Landing Craft Tank, finite element, fatigue life .

Simulation and Evaluation of Dust Emission with Polair3D-SIREAM Model over West Africa Focused on Ouagadougou (Burkina Faso)

The study of air pollution is recent in West Africa. There is a lack of data on air pollution. However, some studies conducted in West Africa show that air quality is a concern. Population growth and massive vehicles imports are contributing to the deterioration of this air quality. In this work, we present the modelling of desert aerosols using a CTM Polair3D-SIREAM. The objective is to evaluate the ability of Polair3D-SIREAM to reproduce observations of PM10 and Aerosol Optical Thicknesses (AOT). A simulation with Polair3D-SIREAM was carried out in West Africa, focused on Ouagadougou (Burkina Faso) for 2007. The model of Marticorena and Bergametti (1995), MB95, was used to estimate desert aerosols emissions. The total emission of dust modelled is 52.2 Tg. For the evaluation of PM10, the simulated averages remained within the same orders of magnitude as the observed averages. Correlations are low in all the observation sites. The other indicators are similar to those found by Schmechtig et al. (2011). Performance criteria of Boylan and Russel (2006) are met for the observation sites of Ouagadougou and Ilorin (Nigeria). For the AOTs, the correlations are significantly improved, in particular, at the sites of Ouagadougou and Ilorin. Performance criteria of Boylan are met for all observation sites. However, the performance goals are only achieved for Ouagadougou and Ilorin.

Rapid Time Response: A solution for Manufacturing Issue

Respond time in manufacturing give the major impact that able to contribute too many manufacturing issues. Based on two worst case scenario occurred where Toyota in 2009 made a massive vehicles call due to car complexity of 11 major models and over 9 million vehicles. The recalls cost at least $2 billion in cost of repair, lost deals and result in lost 5% of its market share in United State of America, while A380 was reported on missing target in new production and leads to delayed market entry due to their weak product life cycle management (PLM). These cases give a sign to all industries to possess and optimize the facilities for better traceability in shortest time period. In Industry 4.0, the traceability and time respond become the factors for high performance manufacturing and rapid time respond able to expedite the traceability process and strengthen the communication level between man, machine and management. The round trip time (RTT) experiment gives variant time respond between two difference operating system for intra and inter-platform signal. If this rapid time respond is adopted in any manufacturing process, the delay in traceability on every issue that lead to losses can be successfully avoided.

Research of Charging(Discharging) Orderly and Optimizing Load Curve for Electric Vehicles Based on Dynamic Electric Price and V2G

Firstly, using the Monte Carlo method and simulation analysis, this paper builds models for the behaviour of electric vehicles, the conventional charging model and the fast charging model. Secondly, this paper studies the impact that the number of electric vehicles which get access to power grid has on the daily load curve. Then, the paper put forwards a dynamic pricing mechanism of electricity, and studies how this dynamic pricing mechanism guides the electric vehicles to charge orderly. Last but not the least, the paper presents a V2G mechanism. Under this mechanism, electric vehicles can charge orderly and take part in the peak shaving. Research finds that massive electric vehicles’ access to the power grid will increase the peak-valley difference of daily load curve. Dynamic pricing mechanism and V2G mechanism can effectively lead the electric vehicles to take part in peak-shaving, and optimize the daily load curve.

Establishing cycler trajectories between Earth and Mars

Several cycler concepts have been proposed to provide safe and comfortable quarters for astronauts traveling between the Earth and Mars. However, no literature has appeared to show how these massive vehicles might be placed into their cycler trajectories. In this paper, trajectories are designed that use either V∞ leveraging or low thrust to establish cycler vehicles in their desired orbits. In the cycler trajectory cases considered, the use of V∞ leveraging or low thrust substantially reduces the total propellant needed to achieve the cycler orbit compared to direct orbit insertion. In the case of the classic Aldrin cycler, the propellant savings due to V∞ leveraging can be as large as 24 metric tons for a cycler vehicle with a dry mass of 75 metric tons, and an additional 111 metric tons by instead using low thrust. The two-synodic period cyclers considered benefit less from V∞ leveraging, but have a smaller total propellant mass due to their lower approach velocities at Earth and Mars. It turns out that, for low-thrust establishment, the propellant required is approximately the same for each of the cycler trajectories. The cycler concept may provide a crucial enabling technology that is safe, economical, and sustainable for the continuous habitation of Mars.

A dynamic evacuation model for pedestrian–vehicle mixed-flow networks

In urban emergency evacuation, a potentially large number of evacuees may depend either on transit or other modes, or need to walk a long distance, to access their passenger cars. In the process of approaching the designated pick-up points or parking areas for evacuation, the massive number of pedestrians may cause tremendous burden to vehicles in the roadway network. Responsible agencies often need to contend with congestion incurred by massive vehicles emanating from parking garages, evacuation buses generated from bus stops, and the conflicts between evacuees and vehicles at intersections. Hence, an effective plan for such evacuation needs to concurrently address both the multi-modal traffic route assignment and the optimization of network signal controls for mixed traffic flows. This paper presents an integrated model to produce the optimal distribution of vehicle and pedestrian flows, and the responsive network signal plan for massive mixed pedestrian–vehicle flows within the evacuation zone. The proposed model features its effectiveness in accounting for multiple types of evacuation vehicles, the interdependent relations between pedestrian and vehicle flows via some conversion locations, and the inevitable conflicts between intersection turning vehicle and pedestrian flows. An illustrating example concerning an evacuation around the M&T stadium area has been presented, and the results indicate the promising properties of our proposed model, especially on reflecting the complex interactions between vehicle and pedestrian flows and the favorable use of high-occupancy vehicles for evacuation operations.

Docking of spacecraft in an elliptical orbit

It is an accepted fact [3] that the docking stage commences at the instant of first contact between the docking devices and is completed as soon as the vehicles are rigidly locked into a unit system. If an impact docking mechanism is used, the actual docking process is divided into two phases. The first phase includes first contact, meshing of the docking devices, and mutual stabilization of the vehicles. The second stage comprises the subsequent locking-in of the bodies. In the first phase the kinetic energy of relative motion is converted into potential energy of elastic deformations, thermal energy, vibrational energy, etc. In the second or locking phase the potential energy of the elastic deformations created in locking together two massive vehicles along a line that does not pass through the centers of mass is partially converted into kinetic energy. Our main objective here is to construct a fairly simple mathematical model of the docking of two spacecraft in an elliptical orbit. Such a model is needed primarily to ensure on-line analysis and drafting of recommendations for the suppression of vibrations of the investigated vehicle coupling in the first docking phase and to control the motions of the vehicles in the second phase with allowance for the possibility of employing vernier engines of one or both vehicles in manual control.