Stress Analysis of Three Marginal Configurations of Full Posterior Crowns by Three-Dimensional Photoelasticity

A simplified method was developed by which three-dimensional composite photoelastic models were constructed. The optimum marginal configuration for the stress distribution was determined and was found to be of the chamfer type.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66544/2/10.1177_00220345740530052501.pd

Smart technologies for effective reconfiguration: the FASTER approach

Current and future computing systems increasingly require that their functionality stays flexible after the system is operational, in order to cope with changing user requirements and improvements in system features, i.e. changing protocols and data-coding standards, evolving demands for support of different user applications, and newly emerging applications in communication, computing and consumer electronics. Therefore, extending the functionality and the lifetime of products requires the addition of new functionality to track and satisfy the customers needs and market and technology trends. Many contemporary products along with the software part incorporate hardware accelerators for reasons of performance and power efficiency. While adaptivity of software is straightforward, adaptation of the hardware to changing requirements constitutes a challenging problem requiring delicate solutions. The FASTER (Facilitating Analysis and Synthesis Technologies for Effective Reconfiguration) project aims at introducing a complete methodology to allow designers to easily implement a system specification on a platform which includes a general purpose processor combined with multiple accelerators running on an FPGA, taking as input a high-level description and fully exploiting, both at design time and at run time, the capabilities of partial dynamic reconfiguration. The goal is that for selected application domains, the FASTER toolchain will be able to reduce the design and verification time of complex reconfigurable systems providing additional novel verification features that are not available in existing tool flows

TOWARD EASING THE INSTANTIATION OF APPLICATIONS USING GRENJ FRAMEWORK BY MEANS OF A DOMAIN SPECIFIC LANGUAGE

White-box frameworks are a collection of extensible classes representing reusable designs that can be extended, to varying degrees, to instantiate custom-tailored software systems. Due to its inherent benefits (e.g., large-scale reuse of code, design, and domain knowledge), such domain-specific reuse approach has become a de facto standard to implement business systems. However, in order to fully realize the advantages of white-box frameworks, developers need to have substantial architectural and technical knowledge. In effect, developers must be familiar with the framework's extension points (e.g., hot spots) and how to program those extensions using the programming language in which the framework was implemented. GRENJ is a white-box framework implemented in Java. Thus, instantiating applications through such framework is quite complex and demands detailed architectural knowledge and advanced Java programming skills. In order to lessen the amount of source code, effort, and expertise required to instantiate applications by using GRENJ framework, we have developed a domain specific language that manages all application instantiation issues systematically. This domain specific language facilitates the application instantiation process by acting as a facade over GRENJ framework as well as providing the user with a more concise, human-readable syntax than Java. In this paper, we contrast the major differences and benefits resulting from instantiating applications solely using GRENJ framework and indirectly reusing its source code by applying our domain specific language.White-box frameworks are a collection of extensible classes representing reusable designs that can be extended, to varying degrees, to instantiate custom-tailored software systems. Due to its inherent benefits (e.g., large-scale reuse of code, design, and domain knowledge), such domain-specific reuse approach has become a de facto standard to implement business systems. However, in order to fully realize the advantages of white-box frameworks, developers need to have substantial architectural and technical knowledge. In effect, developers must be familiar with the framework's extension points (e.g., hot spots) and how to program those extensions using the programming language in which the framework was implemented. GRENJ is a white-box framework implemented in Java. Thus, instantiating applications through such framework is quite complex and demands detailed architectural knowledge and advanced Java programming skills. In order to lessen the amount of source code, effort, and expertise required to instantiate applications by using GRENJ framework, we have developed a domain specific language that manages all application instantiation issues systematically. This domain specific language facilitates the application instantiation process by acting as a facade over GRENJ framework as well as providing the user with a more concise, human-readable syntax than Java. In this paper, we contrast the major differences and benefits resulting from instantiating applications solely using GRENJ framework and indirectly reusing its source code by applying our domain specific language

Spin tunnelling in mesoscopic systems

We study spin tunnelling in molecular magnets as an instance of a mesoscopic phenomenon, with special emphasis on the molecule Fe8. We show that the tunnel splitting between various pairs of Zeeman levels in this molecule oscillates as a function of applied magnetic field, vanishing completely at special points in the space of magnetic fields, known as diabolical points. This phenomena is explained in terms of two approaches, one based on spin-coherent-state path integrals, and the other on a generalization of the phase integral (or WKB) method to difference equations. Explicit formulas for the diabolical points are obtained for a model Hamiltonian.Comment: 13 pages, 5 figures, uses Pramana style files; conference proceedings articl

Quality of Service Driven Runtime Resource Allocation in Reconfigurable HPC Architectures

Heterogeneous System Architectures (HSA) are gaining importance in the High Performance Computing (HPC) domain due to increasing computational requirements coupled with energy consumption concerns, which conventional CPU architectures fail to effectively address. Systems based on Field Programmable Gate Array (FPGA) recently emerged as an effective alternative to Graphical Processing Units (GPUs) for demanding HPC applications, although they lack the abstractions available in conventional CPU-based systems. This work tackles the problem of runtime resource management of a system using FPGA-based co-processors to accelerate multi-programmed HPC workloads. We propose a novel resource manager able to dynamically vary the number of FPGAs allocated to each of the jobs running in a multi-accelerator system, with the goal of meeting a given Quality of Service metric for the running jobs measured in terms of deadline or throughput. We implement the proposed resource manager in a commercial HPC system, evaluating its behavior with representative workloads