Ant Colony Heuristic for Mapping and Scheduling Tasks and Communications on Heterogeneous Embedded Systems

To exploit the power of modern heterogeneous multiprocessor embedded platforms on partitioned applications, the designer usually needs to efficiently map and schedule all the tasks and the communications of the application, respecting the constraints imposed by the target architecture. Since the problem is heavily constrained, common methods used to explore such design space usually fail, obtaining low-quality solutions. In this paper, we propose an ant colony optimization (ACO) heuristic that, given a model of the target architecture and the application, efficiently executes both scheduling and mapping to optimize the application performance. We compare our approach with several other heuristics, including simulated annealing, tabu search, and genetic algorithms, on the performance to reach the optimum value and on the potential to explore the design space. We show that our approach obtains better results than other heuristics by at least 16% on average, despite an overhead in execution time. Finally, we validate the approach by scheduling and mapping a JPEG encoder on a realistic target architecture

A Multi-layer Fpga Framework Supporting Autonomous Runtime Partial Reconfiguration

Partial reconfiguration is a unique capability provided by several Field Programmable Gate Array (FPGA) vendors recently, which involves altering part of the programmed design within an SRAM-based FPGA at run-time. In this dissertation, a Multilayer Runtime Reconfiguration Architecture (MRRA) is developed, evaluated, and refined for Autonomous Runtime Partial Reconfiguration of FPGA devices. Under the proposed MRRA paradigm, FPGA configurations can be manipulated at runtime using on-chip resources. Operations are partitioned into Logic, Translation, and Reconfiguration layers along with a standardized set of Application Programming Interfaces (APIs). At each level, resource details are encapsulated and managed for efficiency and portability during operation. An MRRA mapping theory is developed to link the general logic function and area allocation information to the device related physical configuration level data by using mathematical data structure and physical constraints. In certain scenarios, configuration bit stream data can be read and modified directly for fast operations, relying on the use of similar logic functions and common interconnection resources for communication. A corresponding logic control flow is also developed to make the entire process autonomous. Several prototype MRRA systems are developed on a Xilinx Virtex II Pro platform. The Virtex II Pro on-chip PowerPC core and block RAM are employed to manage control operations while multiple physical interfaces establish and supplement autonomous reconfiguration capabilities. Area, speed and power optimization techniques are developed based on the developed Xilinx prototype. Evaluations and analysis of these prototype and techniques are performed on a number of benchmark and hashing algorithm case studies. The results indicate that based on a variety of test benches, up to 70% reduction in the resource utilization, up to 50% improvement in power consumption, and up to 10 times increase in run-time performance are achieved using the developed architecture and approaches compared with Xilinx baseline reconfiguration flow. Finally, a Genetic Algorithm (GA) for a FPGA fault tolerance case study is evaluated as a ultimate high-level application running on this architecture. It demonstrated that this is a hardware and software infrastructure that enables an FPGA to dynamically reconfigure itself efficiently under the control of a soft microprocessor core that is instantiated within the FPGA fabric. Such a system contributes to the observed benefits of intelligent control, fast reconfiguration, and low overhead

Social Risk and the Transformation of Public Health Law: Lessons from the Plague Years

Acquired Immune Deficiency Syndrome (AIDS) was the wake-up call that disturbed America from its mid-twentieth century slumber concerning the dangers of communicable diseases. Until AIDS was identified in 1981, most Americans felt largely impervious to health threats posed by viruses or bacteria. Polio, smallpox, and tuberculosis had been brought under control by the magic bullets of antibiotics and vaccines. We felt more susceptible to the ravages of cancer or the debilitation of heart disease. But, over the last twenty years, the (re)emergence of serious or life-threatening microbial- based conditions such as Ebola, hantavirus, Lyme disease, West Nile virus, and even newly-recognized strains of hepatitis have underscored our vulnerability. History teaches that new plagues will continue to emerge. What does this mean for the development of public health law and policy? Each epidemic provokes legal and political challenges that raise basic questions about our conceptions of social justice and that shape the development of our public health jurisprudence. How do we identify those at risk or those in need of care? Is it ethical to force people to learn they are ill if no cure exists for their underlying disease? How do we protect those who are healthy from becoming ill? In a world of limited resources, how do we distribute available or emerging treatment? How do we protect those who have fallen ill from inappropriate discrimination or other harms? It is an enormous challenge to determine how these decisions should be made and who should make them. To address these and other problems in the current state of public health law, I propose a Harm Assessment Protocol that will aid legislators and policymakers as they tackle the challenge of modernizing this area of law. This Protocol will allow them to avoid-or at least mitigate-the harms that otherwise might derive from implementing a health-based statutory proposal that may be attractive to or popular with the general public, but which is not, in reality, likely to benefit the public health. The Harm Assessment Protocol proposed in this Article is designed to bring the voices of the disempowered-if not literally, then at least conceptually-to the halls of the legislature and the offices of policymakers, and it relies on these cogent critiques of the primacy of autonomy. Instead of relegating social risk considerations to the end of the process, when they often are ignored or overlooked, my multi-prong analysis begins with an inquiry into such factors. This Article begins by reviewing historical and modem approaches to disease control, emphasizing the fact that, despite growing medical breakthroughs, we continue to face profound challenges to our national health and well-being. Part I also identifies the various governmental and political actors who currently are responsible for the development of public health law and policy and explores the limits of their power. This historical and structural background provides a context for the modern questions of public health law and policy addressed later in this Article. Part II examines in greater detail the model public health statute described earlier. Building on Part II\u27s observations, Part III introduces the Harm Assessment Protocol as a means of evaluating public health law and policy, including existing dominant public health law, the model public health statute, and possible future proposals