Automatic Configuration of Parallel Programs for Processor Networks

: This paper describes the mapping algorithm for distributed memory, parallel message passing systems using the objective function to evaluate the optimality of the mapping of a task graph onto a processor graph. Our optimization method is compared with other ones, some of them issuing from artificial intelligence or operations research. In our experiments randomly generated tasks and processor graphs are used. Keywords: static and dynamic mapping, multicomputer, scheduling, load balancing, smoothing. 1 Introduction Optimal planning of parallel program execution in distributed environment of a multicomputer on the basis of message passing solves the response speed. Static and dynamic mappings can be available and effective way of solution. The theory of optimal mapping comes out from the assumption that the program execution time depends upon uniform load of the processors and upon interprocessor communication minimization. In this paper, our attention is concentrated on the diffusio..

Hybrid Task Allocation Tool for Distributed Systems

This paper describes the hybrid approach to task allocation in distributed systems by using problem-solving methods of the artificial intelligence. For the static mapping the objective function is used to evaluate the optimality of the allocation of a task graph onto a processor graph. Together with our optimization method also augmented simulated annealing and heuristic move exchange methods in distributed form are implemented. For dynamic task allocation the semidistributed approach was designed based on the division of processor network topology into independent and symmetric spheres. Distributed static mapping (DSM) and dynamic load balancing (DLB) tools are controlled by user window interface. DSM and DLB tools are integrated together with software monitor (PG PVM) in the graphical GRAPNEL environment. 1. Introduction Optimal planning of parallel program execution in parallel and distributed systems solves the problem of minimization of execution time. The theory of optimal alloc..

Hybrid approach to task allocation in distributed systems

This paper describes the hybrid approach to task allocation in distributed systems by using problem solving methods of the artificial intelligence. For static mapping the objective function is used to evaluate the optimality of the allocation of a task graph onto a processor graph. Together with our optimization method also augmented simulated annealing and heuristic move exchange methods in distributed form are implemented.  For dynamic task allocation the semidistributed approach was designed based on the division of processor network topology into independent and symmetric spheres. Distributed static mapping (DSM) and  dynamic load balancing (DLB) tools are controlled by user window interface. DSM and DLB tools are integrated together with software monitor (PG_PVM) in the graphical GRAPNEL environment

Verification of the system parameters of gear reducer

The paper deals with experimental verification of the system parameters of the gearbox. Mathematically can be the gear describe as system with a flexible coupling. The properties of the system have been described by the differential equals. The differential equations contain two coefficients which describe the behavior of the system. The coefficients are torsional stiffness constant, spring constant. The object of the verification has been the coefficients as critical parameters of the reduction gear reducer

Distributed Mapping Tool under PVM

: This paper describes the mapping algorithm for distributed memory, parallel message passing systems using the objective function to evaluate the optimality of the mapping of a task graph onto a processor graph. Our optimisation method is compared with other ones, some of them issuing from artificial intelligence or operations research. In our experiments randomly generated tasks and processor graphs are used. Keywords: static and dynamic mapping, multicomputer, scheduling, load balancing, smoothing. 1 Introduction Optimal planning of parallel program execution in distributed environment of a multicomputer on the basis of message passing solves the response speed. The theory of optimal mapping comes out from the assumption that the program execution time depends upon uniform load of the processors and upon interprocessor communication minimisation. In this paper, our attention is concentrated on the diffusion method for static mapping. For static mapping a parallel program can be re..

Design and verification of the chip thermal model: the assessment of a power modules resistance to high current peaks

The paper is focused on creating a thermal model which provides information about the thermal conditions in the semiconductor devices. Increasing the current density and pressure on prices make the optimization of thermal systems an important part in the design process. Simulation analysis has become with development of computer technology an excellent equipment to achieve it. In creating the model, we take account of material and geometric parameters of bonded chips. By the simulation we obtain the necessary information about the components and thermal stresses, these results can be applied in the device design procedure and technology of production. Resistance to bonded diodes is determined by chip parameters and bonding parameters such as the number of bundles, their spacing, and material. Resistance in practice is determined by experimentally measuring IFSM, a peak permeable, unrepeatable current. Also, in the work we analysed voltage-current VA characteristics of power diodes such as threshold voltage, also the closing voltage we tested functionality and we observe changes in the behaviour of the component and, last but not least, the characteristics of thermal resistance and thermal impedance that served as elements for the construction of an equivalent model. In the next part of the paper, in the context of the works, the methods of bindings of PCB components are currently being extended and used in current technological processes and we also concentrate on the dimensional parameters of the modules used to create an equivalent electrical circuit. The presented assembled simplified model respects the chip size, number of bonding wires, and their layout on the chip. For the concept of nine bonds, we had two types of placement from a variety of bonds, so we also respected this factor in the design of the model. As an example, there is a diode module investigated (SKEE SEMIPACK® 2, 1600V/174A)

Possible operation modes of HEV vehicle with direct AC/AC transfer and 5-phase traction motors

The paper deals with operational modes of HEV vehicle with direct AC/AC transfer and five-phase IM traction motors. Such configuration yields smaller voltage drops compared with the serial AC/DC/AC converter and five-phase machines offer some inherent advantages over their three-phase counterparts. Also, dynamical properties of HEV are better due to the absence of a DC link which has accumulating action. Other advantage includes reduced electromagnetic torque pulsation and also noise characteristics of the five-phase drives are better when compared with the three-phase ones. Possible operational modes enable to provide both the single and/or hybrid operations at driving and braking states