Journal of Microcomputer Applications最新文献

This paper presents an efficient architecture for the rendering and display sections of a vehicle simulator prototype. The architecture for the rendering stage, which consists of three independent concurrent units, has been optimised to support the two-layer dynamic load balancing technique. The display stage has also been partitioned to facilitate parallel updating of the pixel data to the dual frame buffers. The design of the frame buffers and the interface logic to access them by direct memory access (DMA) controllers (via three common address and data buses) and the colour video controller are also presented. Simulation results show that the adoption of DMA based memory transfer between the local memory of the transputer nodes and the frame buffers can alleviate the communication bottleneck prevalent in an earlier prototype.

A fuzzy logic control scheme based on the variable structure system concept is presented. This scheme is introduced to eliminate the necessity of relying on the mathematical description of the system. The rule-based fuzzy model is developed in a linguistic description of the dynamic characteristics of the controlled process. Simulation results demonstrate the effectiveness of the proposed scheme as compared with the conventional variable structure systems.

A technique for evaluating the performance of an Am29300 microprogrammable computer board in comparison to a host (an MC68020 single-board computer) is presented. The Am29300 microprogrammable computer board in this application is used as a coprocessor to a general-purpose MC68020 single-board computer. The Am29300 microprogrammable coprocessor board is used for speeding up the highly-repetitive and time-consuming floating point processing functions involved in three-dimensional image generation. The performance analysis of the Am29300 micro-programmable coprocessor is evaluated in terms of MC68020 processor clock cycles. A mathematical expression, containing floating-point operations is chosen as an application example. The analysis in this application has shown that the Am29300 microprogrammable coprocessor is eight times faster than the MC68020, six times faster than the MC68030, and twice as fast as the MC86040 processor.

This paper describes the design and development of an eight-channel ambulatory monitor for use in ergonomic and rehabilitation studies. This portable, battery operated instrument is capable of recording various physiological and biomechanical parameters during the course of a working shift. By incorporating a digital signal processor within the instrument, sophisticated on-line processing is possible. The processed data is stored in a removable non-volatile memory module which can be interrogated by a PC type machine. Evaluation of the instrument in a laboratory setting has been performed to verify operation. In addition, clinical trials are presently underway in a hospital environment as part of an injury prevention program targeted towards nurses. It is proposed that this instrument can be used to determine compliance with such programs after the initial training phase and give some indication as to whether refresher courses are warranted.

A novel method of electrically emulating an area array charge coupled device (CCD) using a personal computer is described in this paper. A dual port memory is used to simulate the photosensitive area of the CCD. Suitable clocks are also generated as is done in the actual CCD system.

The CCD emulation system is useful for the development of any hardware and software which interfaces with a CCD. This system is used to test the on-board micro-processor used in the Indian Remote Sensing (IRS-1C) satellite.

Remote Procedure Call (RPC) has become a popular paradigm for distributed application development in a client-server environment. It is simple, flexible and powerful. Most of the RPC mechanisms today are synchronous in nature, and hence fail to exploit fully the parallelism inherent in distributed applications. The authors have designed and implemented a transport independent asynchronous RPC mechanism (ASTRA) that combines the advantages of both RPC and the message-passing IPC. ASTRA calls do not block the caller (client) and the replies can be received as and when they are needed, thus allowing the client execution to proceed locally in parallel with the server invocation. All the calls are received and executed by the server in the order called by the client. ASTRA is unique among other asynchronous RPC systems in allowing its users to explicitly specify whether low-latency or high-throughput is required for a call. This paper describes the ASTRA primitives and a client-server based application developed using ASTRA. The performance results of the application are briefly summarized to show the suitability of ASTRA for distributed application development.