Comparison of Scheduling Rules in a Flow Shop with Multiple Processors: A SimulationBrah, Shaukat A.; Wheeler, Gloria E.
doi: 10.1177/003754979807100501pmid: N/A
This simulation study investigated the effect on mean flow time and makespan of localized scheduling rules with dynamically established priorities in a flow shop with multiple processors. The study examined the effects of problem characteristics (number of jobs, number of machine stages and number of parallel processors at each stage) and the performance of priority rules using regression analysis. Although structural characteristics explained most of the variation in performance, priority rules also had an effect. The "shortest processing time first" rule was consistently superior; its superiority was greater for mean flow time than for makespan.
Simulation of Optical Fiber Transmission Systems Using SPW on an HP WorkstationHaocheng Zheng, ; Shizhong Xie, ; Zucheng Zhou, ; Bingkun Zhou,
doi: 10.1177/003754979807100502pmid: N/A
In this article, an intensity modulation-direct detection (IM-DD) optical fiber transmission system is simulated and investigated using a signal processing worksystem (SPW) on a Hewlett-Packard (HP) workstation. The optical fiber transmission system simulated includes a laser diode source, a single-mode fiber and a positive-intrinsic-negative (p-i-n) photodiode receiver model. Simulation methods are pre sented on the optical source waveforms, fiber attenuation and dispersion, and receiver noise. The end-to-end performance of a typical trans mission system is also presented. In the simula tion, models can be made as detailed as neces sary and computer waveforms can be compared directly to measured waveforms. Measured data can be used to accurately characterize functional components, such as sources, fibers and detectors. The impact of noise on the per formance of the transmission system can be observed. SPW software and its usage on HP workstations are introduced.
Strategic Planning Simulation Based on Fuzzy Cognitive Map Knowledge and Dif ferential GameKun Chang Lee, ; Won Jun Lee, ; O Byung Kwon, ; Jae Ho Han, ; Pyung Il Yu,
doi: 10.1177/003754979807100503pmid: N/A
It is very difficult for strategic planning managers to fully understand complex chains of influence process of the changing environment on the per formance of implemented strategy. To resolve this kind of problem, this paper presents a mechanism of integrating fuzzy cognitive map knowledge with a strategic planning simulation, where a fuzzy cognitive map (FCM) helps decision makers under stand the complex dynamics between a certain strategic goal and related environmental factors. We use a differential game mechanism as a main vehicle of strategic planning simulation so that the FCM knowledge-based simulation can be per formed as incorporating time-variant competition. Experiments with a set of numerical examples showed that the performance of the proposed stra tegic planning simulation mechanism can effec tively allow decision makers to build robust stra tegic planning under time-variant competitive situations, and yield very promising results in terms of performance.
Reflections on the History of the Society for Computer Simulation InternationalCrosbie, Roy E.
doi: 10.1177/003754979807100507pmid: N/A
The Simulation Council, which later became the Soci ety for Computer Simulation International, was formed in 1952, four and a half years after the operation of the world's first electronic, stored-program digital com puter in Manchester, England. The original Simulation Council was joined by several other similar Councils in different parts of North America in the formation of Simulation Councils Inc. (SCi). Now known as the Soci ety for Computer Simulation International, the organi zation has nearly 2,000 members throughout the world.