Presents an algorithm for computing a sum of products, realizing a fundamental compound multiply-and-add operation of high-speed arithmetic. Two new cellular pipelined algorithms and architectures (2D and 3D) are prop...
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Presents an algorithm for computing a sum of products, realizing a fundamental compound multiply-and-add operation of high-speed arithmetic. Two new cellular pipelined algorithms and architectures (2D and 3D) are proposed. The initial data and results are binary signed-digit integers. The multipliers are loaded digit-serially, while the multiplicands are loaded in a digit-parallel fashion and the results are produced in the same way. The design is performed in terms of cellular technology, based on an original model of distributed computation (the parallel substitution algorithm). The time- and structural complexity is obtained.
The proceedings contain 37 papers. The special focus in this conference is on Ada in Europe. The topics include: A sceptical assessment;an approach to overcome the software crisis;an executive for ada safety critical ...
ISBN:
(纸本)3540607579
The proceedings contain 37 papers. The special focus in this conference is on Ada in Europe. The topics include: A sceptical assessment;an approach to overcome the software crisis;an executive for ada safety critical applications;developing fault tolerant software in ada for real-time dependable systems;the practical application of safety techniques on an ada based project;ada in mixed language applications;heterogeneous data structures and cross-classification of objects with ada95;an AndF based ada 95 compiler system;performance tuning of a check-out system coded in ada;development of the on-board software;first operational ada application in C.N.E.S;extending the ada 95 initial conditions for preelaboration for use in real-time systems;the use of ada for the ENVISAT-1 simulator;objects at use in nautical simulators;an interface to distributedinteractivesimulation;partitioned ada for remotely invoked services;programming distributed systems with both ada 95 and PVM;distributed object oriented programming and interoperability for ada 95;distributed and parallel systems and HOOD 4;a re-engineering methodology and supporting tool;translating shlaer/mellor object-oriented analysis models into ada95;the introduction of an object-oriented analysis/design method and object-oriented metrics in the software development life-cycle;modeling and validation of tasks with algebraic structured nets;design of concurrent software based on problem concurrency;a successful experiment combining CCSDS SFDUs, X/Motif, HOOD and ada;applying teamwork/ada and RAISE for developing an air traffic control application and breaking through the V and V bottleneck.
This paper presents a performance comparison of real-time system architectures. A discrete event-driven, task-based simulator is developed for evaluating the performance of parallel anddistributedreal-time systems. ...
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This paper presents a performance comparison of real-time system architectures. A discrete event-driven, task-based simulator is developed for evaluating the performance of parallel anddistributedreal-time systems. real-time system components such as processor, network architectures, and scheduling policy are included in the simulator. simulation results show that priority-based communication and scheduling are more suitable for real-time systems than FIFO-based. The strategy of having a dedicated processor, which produces no effect on task execution by scheduling and packet/interrupt handling, is proven to enhance schedulability and predictability. This paper suggests a method for finding an appropriate real-time architecture for users having real-time requirements through the performance prediction of real-time systems.
Chaotic systems are known to generate noise-like signals with a power density spectrum distributed over a certain frequency range. These signals are similar to random noise and can be used as broadband signals for sys...
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Chaotic systems are known to generate noise-like signals with a power density spectrum distributed over a certain frequency range. These signals are similar to random noise and can be used as broadband signals for system simulation and measurement, for simulation of random signals and for communication purposes. Since very simple nonlinear dynamic systems can show chaotic behaviour, its use for generating broadband signals could be an interesting and cost effective alternative to the classical application of noise from natural sources, such as resistors or semiconductor devices. For this purpose, chaotic signal generators have to be tailored to the special purposes and demands of the application. In this paper, the design of chaotic systems generating signals with prescribed probability distribution and power spectrum properties will be considered, their realization as discrete-time, digital and analogue systems will be regarded and design examples will be given. Finally some application examples of broadband signals are presented.
In recent years, the performance of distributedreal-time Database Systems (DRTDBS) have been examined using different simulation models. In these models, the network issues are always being neglected. The networks ar...
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In recent years, the performance of distributedreal-time Database Systems (DRTDBS) have been examined using different simulation models. In these models, the network issues are always being neglected. The networks are usually modeled as simple constant delay servers. However, it is found that the performance of the underlying network has a significant impact on the overall performance of the DRTDBS [1]. The results also showed that unpredictable behavior of the underlying network will give non-constant network transit time which in turn deter the overall system performance. To deal with this impact, different virtual deadline assignment schemes are proposed. The schemes assign a virtual deadline based on the current network condition to those transactions which require a comparatively better performance. Our results demonstrate that dynamically tuning the virtual deadlines of transactions depending on the condition of the network, yields a substantial improvement in the performance of that certain type of transactions without severely affecting the overall system performance.
The paper analyses distributed algorithms used to control network links carrying random data traffic generated by multimedia computing based on local information. distributed computing, multimedia mail, interactive sh...
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The paper analyses distributed algorithms used to control network links carrying random data traffic generated by multimedia computing based on local information. distributed computing, multimedia mail, interactive shopping are just a few examples of applications where the current approaches for traffic control (as foreseen by ITU-TS) are not suitable. Traffic descriptors (other than maybe peak rates) are difficult to determine for the user. Global knowledge of the network state is most of the time obsolete due to latency, and therefore approaches must be imagined which do not rely on such information. The paper analyses the options available for bandwidth management in ATM-based networks carrying predominantly data traffic, develops a rationale for supporting 'fill-in' approaches capable of exploiting very high bandwidth links and quantifies the trade-off associated with these approaches, using both trace driven and event driven simulation.
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