摘要:

AbstractPerformance modeling and analysis of a computation is at the heart of the parallel/distributed processing area. Past research efforts produced the computation structure model that can be used to describe the performance behavior of parallel/distributed software at the computation level. How-ever, the model was used only for shared-memory computations. In this paper, we investigate how the model can be used for computations that use rendezvous message-passing communication. Occam is used as the underlying language to implement the computations. A software tool OCAS (Occam Cost Analysis System) is constructed based on the de-veloped techniques to derive the time cost of a given Occam program.

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760125

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractThis paper studies the performance of a multi-processor computer system, which can be used to execute multiple number of SIMD jobs. Such parallel computer organization contains multiple Control Units (CUs) which share a resource pool of a finite number of Processing Elements (PEs) and operate multiple single-instruction-multiple-data streams (MSIMD).A closed queueing network model of a MSIMD computer system is simulated. In order to investigate the effect of the vector jobs size on the system performance in two different CPU queueing disciplines and for various degrees of multiprogramming, different methods of allocating PEs to CUs are considered.

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760126

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractA new“general purpose”program for the analysis of nonlinear electric circuits is used to study a three-phase transformer in no-load operating conditions.Because an analysis is performed entering the program through a SPICE-like circuit description, the electromagnetic device must be modelized as a nonlinear electric circuit with dissipative and restoring branches, suitable to represent the involved physical phenomena.

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760127

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractThe transient light-off behavior of monolithic catalytic conveners after a cold start is critical to their overall performance. A novel two-dimensional equivalent continuum model was developed to describe the transient operation of these chemical reactors. The modeling equations constitute a system of coupled PDEs whose numerical solution imposes large memory and computational time requirements. A systematic approach was followed to vectorize the application code so that it can run efficiently on a CRAY-2 vector processor. Simulation results indicated that non-uniform flow distributions and ambient heat losses can have significant adverse effects on the light-off performance of the catalytic conveners.

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760128

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractThis article presents a hierarchical adaptive algorithm for controlling a human wrist motion simulator (WMS). The WMS is a computer-controlled, electromechanical system that permits the application of desired forces to the tendons of a human cadaver wrist/hand specimen. The proposed control scheme does not require knowledge of the cadaver specimen's dynamic model, and solves on-line the so-called indeterminate problem that arises because the wrist possesses more actuators than degrees of freedom. Computer simulation results are given for a wrist/hand system under adaptive control, and demonstrate that any desired normal wrist motion can be accurately tracked with the proposed algorithm. Additionally, these simulations indicate that the controller resolves the indeterminate problem redundancy in a physiologic manner and show that the control scheme is robust to parameter uncertainty, actuator and sensor bias and noise, and incomplete state feedback.

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760129

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractThe reasearch, carried on in collaboration with a primary Italian Engineering Society operating in the international market, refers to the construction and utilization in the project phase of a transporting network simulator inside a large dimensions fruit and vegetable market utilizing AGV.The precabled languages available on the market referred to AGV networks allowing a "friendly" approach didn't result to be suitable owing to excessive simplifications introduced and network lay-out limitations that, in any case, would have caused a variance not compatible with simulated reality and study general objectives. Then, we went on constructing and setting up a discrete and stochastic detail simulator able to reply to all exigences of project optimization. In particular, during the research following fundamental points have been considered:–analysis of the transporting network layout through the graphs theory–implementation of algorythms to value and choose minimum paths–assignment, layout and statistics of the missions carried on–simulator statistic validation–planned experimental campaign–determination of the dimensional criticalities present in the system.

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760130

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760131

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor