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The author developed a theory of optimal trajectories for air vehicles with variable wing area and conventional wings. He applied a new theory of singular optimal solutions and…
Abstract
The author developed a theory of optimal trajectories for air vehicles with variable wing area and conventional wings. He applied a new theory of singular optimal solutions and obtained the optimal flight in many cases. At first glance, the results may seem strange however, this is correct and this paper will show how this new theory may be used. The main idea of the research is in using the vehicle's kinetic energy for increasing the range of missiles and projectiles. The author shows that the range of a ballistic warhead can be increased 3‐4 times if an optimal wing is added to the ballistic warhead, especially a wing with variable area. If increased range is not needed, the warhead mass can be increased. The range of big gun shells can also be increased 3‐9 times. The range of aircraft may be improved 3‐15 percent and more. The results can be used for the design of aircraft, missiles, flying bombs and shells of big guns.
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This chapter is a review and discussion of the experience of becoming an Electric Vehicle (EV) owner, with a focus on the importance of online EV communities on social media…
Abstract
This chapter is a review and discussion of the experience of becoming an Electric Vehicle (EV) owner, with a focus on the importance of online EV communities on social media platforms in providing informal support to new owners during the transition into EV ownership and use.
Becoming an EV owner represents a significant disruption to drivers’ very established and comfortable driving practices. Electric cars force their owners to re-think long-habitual aspects of the driving experience, including driving behaviour, refuelling (practicalities and etiquette), route planning, and the extent of the car’s ‘sphere of access’.
Because of this disruption, new EV owners regularly encounter challenges, including charging, range, new technology, route planning, etiquette, and more. People often need support to overcome these challenges, and EV owner groups on social media are an important source of such support; new owners can receive advice on a range of issues. This chapter presents data extracted from EV owner social media group posts, analysing the discussions and advice that EV owners offer one another, and exploring the various forms of important support available to new owners/drivers.
This chapter shows how online EV communities are very actively used by EV owners and are of particular importance for new owners. These communities welcome new owners/drivers, offer support and advice, respond to questions, give recommendations, and encourage socialising and a form of group identity/bonding. With EV ownership rapidly increasing in many countries, online EV communities have a very important role to play in helping facilitate the international transition to electric mobility.
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Electric freight vehicles (EFVs) are one of the solutions to improve city logistics’ sustainability. EFVs, that are electric powered light and heavy vehicles with a number plate…
Abstract
Purpose
Electric freight vehicles (EFVs) are one of the solutions to improve city logistics’ sustainability. EFVs, that are electric powered light and heavy vehicles with a number plate, have the potential to make zero emission city logistics possible within the urban area. However, although trials have been undertaken for the last years, large-scale usage of EFVs in city logistics does not occur yet. EFVs are technically possible, but the implementation of EFVs in practice is relatively limited.
Design
This chapter examines by reviewing current and past EFV implementations, what are the challenges, barriers and success factors for EFVs in city logistics operations. EFVs have especially positive environmental effects, but are overall usually more expensive (especially in procurement) than conventional vehicles. Besides, other technical and operational issues remain to be solved, and many uncertainties still exist on long-term usage.
Findings
Three main barriers for large-scale EFV uptake are identified. The current logistics concepts are developed for conventional vehicles and should be redesigned to fit EFVs better. Local authorities’ support is essential in order to find a positive (or not too negative) business case. And EFV implementation requires companies that want to be sustainable. This contribution presents examples of how some companies or authorities deal with these barriers.
Value
This chapter concludes by identifying elements that are necessary for acceleration of EFV uptake in city logistics operations.
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Peter V. Buca and James Brausen
The electric vehicle has been viewed as a technological solution to the dual plagues of dwindling fossil fuel supplies and pollutant emissions from gasoline powered vehicles…
Abstract
The electric vehicle has been viewed as a technological solution to the dual plagues of dwindling fossil fuel supplies and pollutant emissions from gasoline powered vehicles. Futurists see a world where most personal transportation is electrically powered with energy supplied by tomorrow's power plants. In that future world, automobile power sources — representing millions of uncontrollable sources of pollution and energy waste — are consolidated into fewer, manageable, generators in fixed locations. With fixed and relatively few sources of pollution, resources can be better focused to provide clean, inexpensive energy for transportation. Many people share this vision of the future but few have been able to see how it can be brought into existence. Initial attempts have focused on legislation to stimulate the development of this market. As with any new technology, the electric vehicle field has developed its own terminology. For purposes of clarity throughout mis paper please bear in mind the following definitions.
S. Tauqeer ul Islam Rizvi, He Linshu and Xu Dajun
The purpose of the paper is to study the variation of optimal burnout angle at the end of the ascent phase and the optimal control deflection during the glide phase, that would…
Abstract
Purpose
The purpose of the paper is to study the variation of optimal burnout angle at the end of the ascent phase and the optimal control deflection during the glide phase, that would maximize the downrange performance of a hypersonic boost-glide waverider, with variation in heat rate and integrated heat load limit.
Design/methodology/approach
The approach used is to model the boost phase so as to optimize the burnout conditions. The nonlinear, multiphase, constraint optimal control problem is solved using an hp-adaptive pseudospectral method.
Findings
The constraint heat load results for the waverider configuration reveal that the integrated heat load can be reduced by more than half with only 10 per cent penalty in the overall downrange of the hypersonic boost-glide vehicle, within a burnout speed range of 3.7 to 4.3 km/s. The angle-of-attack trim control requirements increase with stringent heat rate and integrated heat load bounds. The normal acceleration remains within limits.
Practical implications
The trajectory results imply lower thermal protection system weight because of reduced heat load trajectory profile and therefore lower thermal protection system cost.
Originality/value
The research provides further study on the trajectory design to the hypersonic boost-glide vehicles for medium range application.
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For the crews and assets of the European Union’s (EU’s) Joint Operations available today, but a vast area in the Mediterranean Sea to monitor, detection of small boats and rafts…
Abstract
Purpose
For the crews and assets of the European Union’s (EU’s) Joint Operations available today, but a vast area in the Mediterranean Sea to monitor, detection of small boats and rafts in distress can take up to several days or even fail at all. This study aims to outline how an energy-autonomous swarm of Unmanned Aerial System can help to increase the monitored sea area while minimizing human resource demand.
Design/methodology/approach
A concept for an unattended swarm of solar powered, unmanned hydroplanes is proposed. A swarm operations concept, vehicle conceptual design and an initial vehicle sizing method is derived. A microscopic, multi-agent-based simulation model is developed. System characteristics and surveillance performance is investigated in this delimited environment number of vehicles scale. Parameter variations in insolation, overcast and system design are used to predict system characteristics. The results are finally used for a scale-up study on a macroscopic level.
Findings
Miniaturization of subsystems is found to be essential for energy balance, whereas power consumption of subsystems is identified to define minimum vehicle size. Seasonal variations of solar insolation are observed to dominate the available energy budget. Thus, swarm density and activity adaption to solar energy supply is found to be a key element to maintain continuous aerial surveillance.
Research limitations/implications
This research was conducted extra-occupationally. Resources were limited to the available range of literature, computational power number and time budget.
Practical implications
A proposal for a probable concept of operations, as well as vehicle preliminary design for an unmanned energy-autonomous, multi-vehicle system for maritime surveillance tasks, are presented and discussed. Indications on path planning, communication link and vehicle interaction scheme selection are given. Vehicle design drivers are identified and optimization of parameters with significant impact on the swarm system is shown.
Social implications
The proposed system can help to accelerate the detection of ships in distress, increasing the effectiveness of life-saving rescue missions.
Originality/value
For continuous surveillance of expanded mission theatres by small-sized vehicles of limited endurance, a novel, collaborative swarming approach applying in situ resource utilization is explored.
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Stefania Boglietti, Martina Carra, Massimiliano Sotgiu, Benedetto Barabino, Michela Bonera and Giulio Maternini
Nowadays, the increase in the capacity of batteries has laid the foundations for a broader diffusion of electric mobility. However, electric mobility is causing a growing…
Abstract
Nowadays, the increase in the capacity of batteries has laid the foundations for a broader diffusion of electric mobility. However, electric mobility is causing a growing electricity demand as well as the need to increase the diffusion of suitable charging stations. Within these last challenges, drawing on the recent literature, this chapter provides a critical and wide-ranging review of papers dealing with the formulation of the problem of the localisation of electric vehicle (EV) charging points. This problem is approached considering the electric charging infrastructure technologies, localisation criteria and related methodologies. This review shows how the ‘electric mobility revolution’ applies the technological innovations provided by the energy supply systems, and the location of these systems within the urban contexts. Since the technological innovations have different options, achieving an international standard of charging systems is still far away. Moreover, as there are several criteria, parameters and methodologies, and some analytical approaches for the localisation of electric vehicle charging points, the formulation of the ‘localisation’ problem should require the application of multi-criteria analysis to be addressed. Finally, the results show that there is no consensus on technologies, criteria, and methodologies to be adopted. Therefore, this wide-ranging analysis of the literature would be useful to support possible benchmarking and systematisation accordingly.
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Automated guided vehicles have a long history, and with the growth of automation in manufacture and assembly they are becoming an increasingly important element in integrated…
Abstract
Automated guided vehicles have a long history, and with the growth of automation in manufacture and assembly they are becoming an increasingly important element in integrated systems. In this and the following two articles Jack Hollingum looks at a long‐established supplier of AGVs with ideas for the future; a pioneer of free‐ranging vehicles; and a research centre with ideas which could help in taking robot vehicles into completely new types of application.
Luis C. Rabelo, Jose Sepulveda, Jeppie Compton and Robert Turner
The main objective of this paper is to introduce the development of a decision‐support environment for a complex problem: space range safety. Simulation modeling can provide a…
Abstract
Purpose
The main objective of this paper is to introduce the development of a decision‐support environment for a complex problem: space range safety. Simulation modeling can provide a good environment to support range safety managers.
Design/methodology/approach
The paper describes the different models and the processes to find the different knowledge sources. In addition, it investigates statistically the most important factors. This will help determine emergency management procedures and sources of variability.
Findings
This case study provides guidance and an example to follow for other problems in aerospace (in particular new the analysis of new vehicles). There are important factors to consider in order to implement risk management in National Aeronautics and Space Administration.
Research limitations/implications
There are several limitations; blast and debris effects need to be added.
Practical implications
First, it provides a guide in order to persuade managers of the utilization of decision‐support systems based on geographical information systems. Second, it shows that there is open source software (Calpuff in our environment) which can be used and integrated to make a more comprehensive environment. Validation is a big issue. In addition, simulation can help make decisions about future vehicles or events.
Originality/value
This is the first implementation of a virtual range (there is not an integrated system similar to this one available). This will be valuable to other safety managers not only for space exploration but also environmentalists and homeland security managers.
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