864 research outputs found

    Efficient resource allocation for automotive active vision systems

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    Individual mobility on roads has a noticeable impact upon peoples' lives, including traffic accidents resulting in severe, or even lethal injuries. Therefore the main goal when operating a vehicle is to safely participate in road-traffic while minimising the adverse effects on our environment. This goal is pursued by road safety measures ranging from safety-oriented road design to driver assistance systems. The latter require exteroceptive sensors to acquire information about the vehicle's current environment. In this thesis an efficient resource allocation for automotive vision systems is proposed. The notion of allocating resources implies the presence of processes that observe the whole environment and that are able to effeciently direct attentive processes. Directing attention constitutes a decision making process dependent upon the environment it operates in, the goal it pursues, and the sensor resources and computational resources it allocates. The sensor resources considered in this thesis are a subset of the multi-modal sensor system on a test vehicle provided by Audi AG, which is also used to evaluate our proposed resource allocation system. This thesis presents an original contribution in three respects. First, a system architecture designed to efficiently allocate both high-resolution sensor resources and computational expensive processes based upon low-resolution sensor data is proposed. Second, a novel method to estimate 3-D range motion, e cient scan-patterns for spin image based classifiers, and an evaluation of track-to-track fusion algorithms present contributions in the field of data processing methods. Third, a Pareto efficient multi-objective resource allocation method is formalised, implemented, and evaluated using road traffic test sequences

    The STAR MAPS-based PiXeL detector

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    The PiXeL detector (PXL) for the Heavy Flavor Tracker (HFT) of the STAR experiment at RHIC is the first application of the state-of-the-art thin Monolithic Active Pixel Sensors (MAPS) technology in a collider environment. Custom built pixel sensors, their readout electronics and the detector mechanical structure are described in detail. Selected detector design aspects and production steps are presented. The detector operations during the three years of data taking (2014-2016) and the overall performance exceeding the design specifications are discussed in the conclusive sections of this paper

    A Survey of Driving Research Simulators Around the World.

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    The literature review is part of the EPSRC funded project "Driver performance in the EPSRC driving simulator: a validation study". The aim of the project is to validate this simulator, located at the Department of Psychology, University of Leeds, and thereby to indicate the strengths and weaknesses of the existing configuration. It will provide guidance on how the simulator can be modified and overcome any deficiencies that are detected and also provide "benchmarks" against which other simulators can be compared. The literature review will describe the technical characteristics of the most well-known driving simulators around the world, their special features and their application areas until today. The simulators will be described and compared according to their cost (low, medium and high) and also contact addresses and photographs of the simulators will be provided by the end of the paper. In the process of gathering this information, it became apparent that there are mainly two types of papers published - either in journals or in proceedings from conferences: those describing only the technical characteristics of a specific simulator and those referring only to the applications of a specific simulator. For the first type of papers, the level of detail, format and content varies significantly where for the second one it has been proven extremely difficult to find any information about the technical characteristics of the simulator where the study had been carried out. A number of details provided in this paper are part of personal communication, or personal visits to those particular driving simulator centres or from the World Wide Web. It should also be noted here that most of the researchers contacted here offered very detail technical characteristics and application areas of their driving simulators and the author is grateful to them

    Digital Twin and Cloud BIM-XR Platform Development: From Scan-to-BIM-to-DT Process to a 4D Multi-User Live App to Improve Building Comfort, Efficiency and Costs

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    Digital twins (DTs) and building information modelling (BIM) are proving to be valuable tools for managing the entire life cycle of a building (LCB), from the early design stages to management and maintenance over time. On the other hand, BIM platforms cannot manage the geometric complexities of existing buildings and the large amount of information that sensors can collect. For this reason, this research proposes a scan-to-BIM process capable of managing high levels of detail (LODs) and information (LOIs) during the design, construction site management, and construction phases. Specific grades of generation (GOGs) were applied to create as-found, as-designed, and as-built models that interact with and support the rehabilitation project of a multi-level residential building. Furthermore, thanks to the sharing of specific APIs (Revit and Autodesk Forge APIs), it was possible to switch from static representations to novel levels of interoperability and interactivity for the user and more advanced forms of building management such as a DT, a BIM cloud, and an extended reality (XR) web platform. Finally, the development of a live app shows how different types of users (professionals and non-expert) can interact with the DT, in order to know the characteristics with which the environments have been designed, as well as the environmental parameters, increasing their degree of control, from the point of view of improving comfort, use, costs, behaviour, and good practices. Finally, the overall approach was verified through a real case study where the BIM-XR platform was built for energy improvements to existing buildings and facade renovations

    Challenges in imaging and predictive modeling of rhizosphere processes

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    Background Plant-soil interaction is central to human food production and ecosystem function. Thus, it is essential to not only understand, but also to develop predictive mathematical models which can be used to assess how climate and soil management practices will affect these interactions. Scope In this paper we review the current developments in structural and chemical imaging of rhizosphere processes within the context of multiscale mathematical image based modeling. We outline areas that need more research and areas which would benefit from more detailed understanding. Conclusions We conclude that the combination of structural and chemical imaging with modeling is an incredibly powerful tool which is fundamental for understanding how plant roots interact with soil. We emphasize the need for more researchers to be attracted to this area that is so fertile for future discoveries. Finally, model building must go hand in hand with experiments. In particular, there is a real need to integrate rhizosphere structural and chemical imaging with modeling for better understanding of the rhizosphere processes leading to models which explicitly account for pore scale processes

    Design and Validation of Network-on-Chip Architectures for the Next Generation of Multi-synchronous, Reliable, and Reconfigurable Embedded Systems

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    NETWORK-ON-CHIP (NoC) design is today at a crossroad. On one hand, the design principles to efficiently implement interconnection networks in the resource-constrained on-chip setting have stabilized. On the other hand, the requirements on embedded system design are far from stabilizing. Embedded systems are composed by assembling together heterogeneous components featuring differentiated operating speeds and ad-hoc counter measures must be adopted to bridge frequency domains. Moreover, an unmistakable trend toward enhanced reconfigurability is clearly underway due to the increasing complexity of applications. At the same time, the technology effect is manyfold since it provides unprecedented levels of system integration but it also brings new severe constraints to the forefront: power budget restrictions, overheating concerns, circuit delay and power variability, permanent fault, increased probability of transient faults. Supporting different degrees of reconfigurability and flexibility in the parallel hardware platform cannot be however achieved with the incremental evolution of current design techniques, but requires a disruptive approach and a major increase in complexity. In addition, new reliability challenges cannot be solved by using traditional fault tolerance techniques alone but the reliability approach must be also part of the overall reconfiguration methodology. In this thesis we take on the challenge of engineering a NoC architectures for the next generation systems and we provide design methods able to overcome the conventional way of implementing multi-synchronous, reliable and reconfigurable NoC. Our analysis is not only limited to research novel approaches to the specific challenges of the NoC architecture but we also co-design the solutions in a single integrated framework. Interdependencies between different NoC features are detected ahead of time and we finally avoid the engineering of highly optimized solutions to specific problems that however coexist inefficiently together in the final NoC architecture. To conclude, a silicon implementation by means of a testchip tape-out and a prototype on a FPGA board validate the feasibility and effectivenes

    V/STOL flight control functionality research to improve handling qualities in the jetborne and semi-jetborne flight regimes

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    Since the 1950\u27s, several nations have attempted to build Vertical and Short Takeoff and Landing (V/STOL) jet fighter aircraft in a variety of configurations. One of the greatest challenges of each design team was in designing and implementing a flight control system that reduced pilot workload to an acceptable level during the transition from conventional flight to fully jetborne flight. Not all the ideas worked, and even the more successful aircraft were difficult and dangerous to fly. Pilot workload of the only currently operated V/STOL attack fighter design, the Harrier, was reduced by installing limited authority augmented flight controls to increase aircraft stability, but still it remains more difficult to fly than conventional aircraft. The United States Marine Corps (USMC) and the United Kingdom\u27s Royal Air Force (RAF) and Royal Navy (RN) have decided to replace their aging Harrier fleet of aircraft with an affordable next generation Short Takeoff and Vertical Landing (STOVL) strike fighter. All three services require the new STOVL aircraft to possess vast improvements in handling qualities over the Harrier. This thesis examines the solutions to reduce the excessive workload associated with V/STOL flight. In this thesis, specific comments on individual evaluated mode effects on handling qualities will be addressed, while deficiencies due to individual inceptor mechanical characteristics will be minimized. The analysis and solutions are based on the author\u27s research, extensive Harrier flight time, and recent V/STOL flight test experience. The coupling of a highly augmented digital flight control system with STOVL task optimized, blended control response types controlled by an intuitive flight control inceptor scheme would greatly improve the handling qualities of an advanced STOVL strike fighter. The preferred inceptor scheme includes a left inceptor, a right center inceptor with an attitude trim switch and a thumbwheel, and control pedals. During STOVL operations, the recommended response type blended flight control design includes: sideslip command blended into yaw rate command on the control pedals, flightpath command blended into height rate command on the left inceptor, roll rate command with attitude hold blended into roll attitude command with natural ground referenced lateral acceleration coupling on the right inceptor lateral axis with crosswind compensation, flightpath command blended into pitch attitude command with augmented natural ground referenced longitudinal acceleration coupling on the right inceptor longitudinal axis, pitch and roll attitude right inceptor trim switch for use in the slow speed flight region, Translational Rate Command sub-mode option with the right inceptor, and flightpath referenced acceleration command blended into ground referenced acceleration command on the right inceptor located thumbwheel with speed hold detent. Implementation of the above concepts would greatly improve handling qualities in the STOVL flight regime. It has been decided that there is an advantage for the next generation of strike fighter to have a STOVL flight capability, but without increased operational cost or risk. To insure these requirements are satisfied, the aircraft contractors and military must use the existing technologies available to vastly reduce the pilot workload over past and current V/STOL aircraft designs
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