Memory-Aware Scheduling for Fixed Priority Hard Real-Time Computing Systems

As a major component of a computing system, memory has been a key performance and power consumption bottleneck in computer system design. While processor speeds have been kept rising dramatically, the overall computing performance improvement of the entire system is limited by how fast the memory can feed instructions/data to processing units (i.e. so-called memory wall problem). The increasing transistor density and surging access demands from a rapidly growing number of processing cores also significantly elevated the power consumption of the memory system. In addition, the interference of memory access from different applications and processing cores significantly degrade the computation predictability, which is essential to ensure timing specifications in real-time system design. The recent IC technologies (such as 3D-IC technology) and emerging data-intensive real-time applications (such as Virtual Reality/Augmented Reality, Artificial Intelligence, Internet of Things) further amplify these challenges. We believe that it is not simply desirable but necessary to adopt a joint CPU/Memory resource management framework to deal with these grave challenges. In this dissertation, we focus on studying how to schedule fixed-priority hard real-time tasks with memory impacts taken into considerations. We target on the fixed-priority real-time scheduling scheme since this is one of the most commonly used strategies for practical real-time applications. Specifically, we first develop an approach that takes into consideration not only the execution time variations with cache allocations but also the task period relationship, showing a significant improvement in the feasibility of the system. We further study the problem of how to guarantee timing constraints for hard real-time systems under CPU and memory thermal constraints. We first study the problem under an architecture model with a single core and its main memory individually packaged. We develop a thermal model that can capture the thermal interaction between the processor and memory, and incorporate the periodic resource sever model into our scheduling framework to guarantee both the timing and thermal constraints. We further extend our research to the multi-core architectures with processing cores and memory devices integrated into a single 3D platform. To our best knowledge, this is the first research that can guarantee hard deadline constraints for real-time tasks under temperature constraints for both processing cores and memory devices. Extensive simulation results demonstrate that our proposed scheduling can improve significantly the feasibility of hard real-time systems under thermal constraints

Proceedings of the Third Edition of the Annual Conference on Wireless On-demand Network Systems and Services (WONS 2006)

Ce fichier regroupe en un seul documents l'ensemble des articles accéptés pour la conférences WONS2006/http://citi.insa-lyon.fr/wons2006/index.htmlThis year, 56 papers were submitted. From the Open Call submissions we accepted 16 papers as full papers (up to 12 pages) and 8 papers as short papers (up to 6 pages). All the accepted papers will be presented orally in the Workshop sessions. More precisely, the selected papers have been organized in 7 session: Channel access and scheduling, Energy-aware Protocols, QoS in Mobile Ad-Hoc networks, Multihop Performance Issues, Wireless Internet, Applications and finally Security Issues. The papers (and authors) come from all parts of the world, confirming the international stature of this Workshop. The majority of the contributions are from Europe (France, Germany, Greece, Italy, Netherlands, Norway, Switzerland, UK). However, a significant number is from Australia, Brazil, Canada, Iran, Korea and USA. The proceedings also include two invited papers. We take this opportunity to thank all the authors who submitted their papers to WONS 2006. You helped make this event again a success

Technology 2002: The Third National Technology Transfer Conference and Exposition, volume 2

Proceedings from symposia of the Technology 2002 Conference and Exposition, December 1-3, 1992, Baltimore, MD. Volume 2 features 60 papers presented during 30 concurrent sessions

Actuators for Intelligent Electric Vehicles

This book details the advanced actuators for IEVs and the control algorithm design. In the actuator design, the configuration four-wheel independent drive/steering electric vehicles is reviewed. An in-wheel two-speed AMT with selectable one-way clutch is designed for IEV. Considering uncertainties, the optimization design for the planetary gear train of IEV is conducted. An electric power steering system is designed for IEV. In addition, advanced control algorithms are proposed in favour of active safety improvement. A supervision mechanism is applied to the segment drift control of autonomous driving. Double super-resolution network is used to design the intelligent driving algorithm. Torque distribution control technology and four-wheel steering technology are utilized for path tracking and adaptive cruise control. To advance the control accuracy, advanced estimation algorithms are studied in this book. The tyre-road peak friction coefficient under full slip rate range is identified based on the normalized tyre model. The pressure of the electro-hydraulic brake system is estimated based on signal fusion. Besides, a multi-semantic driver behaviour recognition model of autonomous vehicles is designed using confidence fusion mechanism. Moreover, a mono-vision based lateral localization system of low-cost autonomous vehicles is proposed with deep learning curb detection. To sum up, the discussed advanced actuators, control and estimation algorithms are beneficial to the active safety improvement of IEVs

The Multi-Agent Transport Simulation MATSim

"The MATSim (Multi-Agent Transport Simulation) software project was started around 2006 with the goal of generating traffic and congestion patterns by following individual synthetic travelers through their daily or weekly activity programme. It has since then evolved from a collection of stand-alone C++ programs to an integrated Java-based framework which is publicly hosted, open-source available, automatically regression tested. It is currently used by about 40 groups throughout the world. This book takes stock of the current status. The first part of the book gives an introduction to the most important concepts, with the intention of enabling a potential user to set up and run basic simulations.The second part of the book describes how the basic functionality can be extended, for example by adding schedule-based public transit, electric or autonomous cars, paratransit, or within-day replanning. For each extension, the text provides pointers to the additional documentation and to the code base. It is also discussed how people with appropriate Java programming skills can write their own extensions, and plug them into the MATSim core. The project has started from the basic idea that traffic is a consequence of human behavior, and thus humans and their behavior should be the starting point of all modelling, and with the intuition that when simulations with 100 million particles are possible in computational physics, then behavior-oriented simulations with 10 million travelers should be possible in travel behavior research. The initial implementations thus combined concepts from computational physics and complex adaptive systems with concepts from travel behavior research. The third part of the book looks at theoretical concepts that are able to describe important aspects of the simulation system; for example, under certain conditions the code becomes a Monte Carlo engine sampling from a discrete choice model. Another important aspect is the interpretation of the MATSim score as utility in the microeconomic sense, opening up a connection to benefit cost analysis. Finally, the book collects use cases as they have been undertaken with MATSim. All current users of MATSim were invited to submit their work, and many followed with sometimes crisp and short and sometimes longer contributions, always with pointers to additional references. We hope that the book will become an invitation to explore, to build and to extend agent-based modeling of travel behavior from the stable and well tested core of MATSim documented here.

Towards a sustainable PV waste policy: Exploring the management practices of end-of-life solar photovoltaic modules in Australia

Solar photovoltaic (PV) systems are effective measures to reduce the greenhouse gas emissions. However, the large exploitation of solar PV modules, leads to undesirable waste accumulation, affecting the environment. Solar PV waste management research is an emerging field that has received more attention recently, affected by the increase volume of solar PV disposals. However, only a few studies have examined the current practices in solar photovoltaic waste management. In Australia, because of social and economic factors (such as the replacement of small-scale PV systems come with new rebates), residential solar systems are decommissioned earlier than expected before reaching their end-of-life (EoL). 70% of the market share of PV systems are predominately dominated by the residential market in Australia as of 2020. The average practical lifetime of PV modules instead of 20-30 years is 15-20 years in Australia. Therefore, the volume of EoL PV from the residential sector entering the waste stream in the coming decade will be higher than previously predicted. This study aims to assess the environmental impacts of waste from rooftop solar photovoltaic panels in Australia to inform sustainable policies. To achieve the aim of the research, the following objectives are investigated: 1) exploring the current practices of managing end-oflife rooftop solar photovoltaic panels in Australia; 2) developing an optimised system approach in dealing with solar photovoltaic waste in Australia; and 3) assessing the environmental impacts of end-of-life rooftop solar photovoltaic panels in Australia within the developed assessment framework. To achieve the research objectives, several methods are adopted to analyse the primary and secondary data for this research. A modified Fuzzy Delphi Method (FDM) is adopted in gathering data through interviews and questionnaires from experts in the field. The results show that, crystalline silicon panels were the most common panels on the Australian market and the ones that are being installed frequently. On policies, although the Australian government has banned PV waste from going to landfill since 2014, there were no regulations or action plans to manage PV waste. The absence of policies and regulations results in unregulated movement and tracking of solar PV waste in and out of Australia as well as within and across the states. The extent of the PV recovery and recycling warrants further investigation. Moreover, infrastructure and logistics has been a significant problem because of the geographical spread of the country and how it affects transportation and the supply chain. Findings led to the establishment of a conceptual framework for the current treatment of solar PV waste in Australia. Furthermore, a Weibull distribution model is employed to forecast the PV waste in the next three decades in South Australia. The study further estimates the pollutant emission associated with the collection and transportation of the waste for recycling and recovery. Results indicate that, there will be 109,007 tons of PV waste generated in urban and suburban context in South Australia by 2050. Among the three routing scenarios generated, the third scenario with optimised transfer stations and an additional recycling facility showed more than 34% reduction in pollutant emission. This study evaluates the environmental impacts of three policy options for mono and multi crystalline silicon (c-Si) solar panel waste modules. The impact of transport distance from transfer stations to the recycling centre is also assessed. The life cycle assessment revealed that, -1E+06 kgCO2eq and -2E+06 kgCO2eq are associated with the mandatory product stewardship scenarios under global warming potential for mono and multi c-Si solar modules respectively. However, the non-existence of a product stewardship will produce a global warming impact of 1E+05 kgCO2eq for both modules. The global warming effects revealed that, collecting and recycling most of the multi c-Si panels were not effective (-365 kg CO2-eq, -698.4 kg CO2-eq, -1032 kg CO2-eq) compared to keeping them away from the landfills and fully recycling (- 2E+06 kg CO2-eq) them. It was also highlighted that, the highest environmental impact regarding the transport distances was the scenario of one recycling centre serving over 107 transfer stations with a global warming potential of 1E+06 kgCO2eq. In conclusion, this study contributes to the management of the supply market of solar PV technologies, using Australia as a case study. The recommendations derived from the study include: creating collection centres for EoL PV modules in South Australia, developing a logistic network to for the collection of EoL PV modules, creating and enhancing the PV recycling market for recovered materials, issuing a regulatory landfill ban for EoL solar PV module in South Australia, developing a mandatory product stewardship for PV waste in Australia, promoting and providing financial incentives to current and future infrastructure for PV recycling, minimising the exportation of PV waste overseas and interstate, encouraging industry led research on new innovations to improve the recovery of different PV technology families, developing sustainable measures to cut emissions for recycling through research and development in South Australia, and building the capacity and promoting awareness on the benefits of PV recycling in South Australia.Thesis (Ph.D.) -- University of Adelaide, School of Architecture and Civil Engineering, 202

Energy aware performance evaluation of WSNs

Distributed sensor networks have been discussed for more than 30 years, but the vision of Wireless Sensor Networks (WSNs) has been brought into reality only by the rapid advancements in the areas of sensor design, information technologies, and wireless networks that have paved the way for the proliferation of WSNs. The unique characteristics of sensor networks introduce new challenges, amongst which prolonging the sensor lifetime is the most important. Energy-efficient solutions are required for each aspect of WSN design to deliver the potential advantages of the WSN phenomenon, hence in both existing and future solutions for WSNs, energy efficiency is a grand challenge. The main contribution of this thesis is to present an approach considering the collaborative nature of WSNs and its correlation characteristics, providing a tool which considers issues from physical to application layer together as entities to enable the framework which facilitates the performance evaluation of WSNs. The simulation approach considered provides a clear separation of concerns amongst software architecture of the applications, the hardware configuration and the WSN deployment unlike the existing tools for evaluation. The reuse of models across projects and organizations is also promoted while realistic WSN lifetime estimations and performance evaluations are possible in attempts of improving performance and maximizing the lifetime of the network. In this study, simulations are carried out with careful assumptions for various layers taking into account the real time characteristics of WSN. The sensitivity of WSN systems are mainly due to their fragile nature when energy consumption is considered. The case studies presented demonstrate the importance of various parameters considered in this study. Simulation-based studies are presented, taking into account the realistic settings from each layer of the protocol stack. Physical environment is considered as well. The performance of the layered protocol stack in realistic settings reveals several important interactions between different layers. These interactions are especially important for the design of WSNs in terms of maximizing the lifetime of the network

Heterogeneous Wireless Networks QoE Framework

With the appearance of small cells and the move of mobile networks towards an all-IP 4G network, the convergence of these with Wi-Fi becomes a possibility which at the same time opens the path to achieve what will become 5G connectivity. This thesis describes the evolution of the different mainstream wireless technologies deployed around the world and how they can interact, and provides tools to use this convergence to achieve the foreseen requirements expected in a 5G environment and the ideal user experience. Several topics were identified as needing attention: handover between heterogeneous networks, security of large numbers of small cells connected via a variety of backhaul technologies to the core networks, edge content distribution to improve latency, improvement of the service provided in challenging radio environments and interference between licensed and unlicensed spectrum. Within these topics a contribution was made to improve the current status by analysing the unaddressed issues and coming up with potential improvements that were tested in trials or lab environment. The main contributions from the study have been: 1. A patent in the wireless security domain that reuses the fact that overlapping coverage is and will be available and protects against man in the middle attacks (Section 5.3). 2. A patent in the content distribution domain that manages to reduce the cost to deliver content within a mobile network by looking for the shortest path to the requested content (Section 6.3). 3. Improvements and interoperability test of 802.21 standard which improves the seamlessness of handovers (Section 4.2). 4. 2 infill trials which focus on how to improve the user experience in those challenging conditions (Sections 7.2 and 7.3). 5. An interference study with Wi-Fi 2.4GHz for the newly allocated spectrum for 4G (Section 8.2). This thesis demonstrates some of the improvements required in current wireless networks to evolve towards 5G and achieve the coverage, service, user experience, latency and security requirements expected from the next generation mobile technology

A Distributed Service Delivery Platform for Automotive Environments: Enhancing Communication Capabilities of an M2M Service Platform for Automotive Application

Full version: Access restricted permanently due to 3rd party copyright restrictions. Restriction set on 11.04.2018 by SE, Doctoral CollegeThe automotive domain is changing. On the way to more convenient, safe, and efficient vehicles, the role of electronic controllers and particularly software has increased significantly for many years, and vehicles have become software-intensive systems. Furthermore, vehicles are connected to the Internet to enable Advanced Driver Assistance Systems and enhanced In-Vehicle Infotainment functionalities. This widens the automotive software and system landscape beyond the physical vehicle boundaries to presently include as well external backend servers in the cloud. Moreover, the connectivity facilitates new kinds of distributed functionalities, making the vehicle a part of an Intelligent Transportation System (ITS) and thus an important example for a future Internet of Things (IoT). Manufacturers, however, are confronted with the challenging task of integrating these ever-increasing range of functionalities with heterogeneous or even contradictory requirements into a homogenous overall system. This requires new software platforms and architectural approaches. In this regard, the connectivity to fixed side backend systems not only introduces additional challenges, but also enables new approaches for addressing them. The vehicle-to-backend approaches currently emerging are dominated by proprietary solutions, which is in clear contradiction to the requirements of ITS scenarios which call for interoperability within the broad scope of vehicles and manufacturers. Therefore, this research aims at the development and propagation of a new concept of a universal distributed Automotive Service Delivery Platform (ASDP), as enabler for future automotive functionalities, not limited to ITS applications. Since Machine-to-Machine communication (M2M) is considered as a primary building block for the IoT, emergent standards such as the oneM2M service platform are selected as the initial architectural hypothesis for the realisation of an ASDP. Accordingly, this project describes a oneM2M-based ASDP as a reference configuration of the oneM2M service platform for automotive environments. In the research, the general applicability of the oneM2M service platform for the proposed ASDP is shown. However, the research also identifies shortcomings of the current oneM2M platform with respect to the capabilities needed for efficient communication and data exchange policies. It is pointed out that, for example, distributed traffic efficiency or vehicle maintenance functionalities are not efficiently treated by the standard. This may also have negative privacy impacts. Following this analysis, this research proposes novel enhancements to the oneM2M service platform, such as application-data-dependent criteria for data exchange and policy aggregation. The feasibility and advancements of the newly proposed approach are evaluated by means of proof-of-concept implementation and experiments with selected automotive scenarios. The results show the benefits of the proposed enhancements for a oneM2M-based ASDP, without neglecting to indicate their advantages for other domains of the oneM2M landscape where they could be applied as well

Sustainable Qatar

This open access book provides a topical overview of the key sustainability issues in Qatar, focusing on environmental sustainability from a socio-political perspective. The transition to a sustainable Qatar requires engagement with diverse areas of social-political, human, and environmental development. On the environmental aspects, the contributors address climate change, food security, water reuse and desalination, energy, and biodiversity. The socio-political section examines state strategy and regulation, the place of environmental law and geopolitics and sustainability innovators and catalysts. The human section considers economics, sustainability education, the knowledge economy, and waste management. In doing so, the book demarcates the ways in which the country encounters and grapples with significant challenges and delves into the range of options for future pathways to sustainability in Qatar. Relevant to policymakers and scholars in energy and environment, urban and developmental studies, as well as the arenas of politics, climate change and policy, this book is a landmark collection on environmental policy in the Gulf and beyond. ; This volume provides a topical overview of the key sustainability issues in Qatar, focusing on environmental sustainability from a socio-political perspective. The transition to a sustainable Qatar weaves together pillars of social-political, human, and environmental development, and so this book tackles each aspect accordingly. In the environmental section, the contributors address climate change, food security, water reuse and desalination, energy, air quality and biodiversity. The socio-political section examines state strategy and regulation, the place of environmental law and geopolitics, and sustainability innovators and catalysts. The human section considers demographic trends and models, economics – including the circular economy and green finance – transport, the built environment, and waste management. In doing so, the volume demarcates the ways in which the country encounters and grapples with significant challenges, and delves into the range of options for future pathways to sustainability in Qatar. Relevant to policymakers and scholars in energy and environment, urban, and developmental studies, as well as the arenas of politics, climate change, and policy, this book is a landmark collection on environmental policy in the Gulf, and beyond