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961.
OMT在企业物流分析中的应用 总被引:2,自引:1,他引:1
文章介绍了面向对象的模型化技术(OMT)的基本概念,分析了它的实现过程,即对象模型、动态模型、和过程模型的建立,并以一个具体的实例说明其在企业物流分析中的应用。 相似文献
962.
基于任务的访问控制系统 总被引:2,自引:0,他引:2
从特点、基本组成、模型系结构以及应用前景这几个方面着手介绍一种新的访问控制模式-基于任务的访问控制(TBAC),并着重说明了基于任务的访问控制模型与传统的访问控制模型的不同点。 相似文献
963.
964.
Matthew Bone 《Journal of the Society for Information Display》2001,9(3):227-232
Abstract— Optical designs for three‐panel LCoS projection systems are reviewed. The impact of polarization aberrations in prism‐based systems is discussed and a simple model to analyze the sensitivity of contrast to thermal gradients in prisms is presented. To eliminate stress birefringence in LCoS projection systems, we have developed a projection optical system that does not require the use of polarizing prisms. An improved off‐axis design has been designed that simplifies manufacture and reduces cost. The performance of systems based on this architecture will be discussed. 相似文献
965.
T.-P. Hong T.-T. Wang S.-L. Wang 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2001,5(6):426-433
Flexible flow shops can be thought of as generalizations of simple flow shops. In the past, the processing time for each
job was usually assumed to be known exactly, but in many real-world applications, processing times may vary dynamically due
to human factors or operating faults. In the past, we demonstrated how discrete fuzzy concepts could easily be used in the
Palmer algorithm for managing uncertain flexible-flow-shop scheduling. In this paper, we generalize it to continuous fuzzy
domains. We use triangular membership functions for flexible flow shops with more than two machine centers to examine processing-time
uncertainties and to make scheduling more suitable for real applications. We first use the triangular fuzzy LPT algorithm
to allocate jobs, and then use the triangular fuzzy Palmer algorithm to deal with sequencing the tasks. The proposed method
thus provides a more flexible way of scheduling jobs than conventional scheduling methods. 相似文献
966.
为解决目前国内电磁流量计无法同时满足高温、高压、耐腐蚀、大通径流量测量的难题,提出了利用小口径电磁流量计,通过测量分流支管中的流体流量,达到替代大口径电磁流量计测量大流量的目的。中还提出了延长电磁流量计使用寿命的措施。 相似文献
967.
信号监控是一种有效的控制流错误检测技术,采用不同的信号函数所引起的性能开销和存储器开销差别很大,为了降低开销,提出了一种新的用于控制流错误检测的信号函数,该信号函数定义于伽罗瓦域中,给发配状态代码和计算状态信号的算法,该算法不是用穷尽搜索的方法而是通过矩阵给状态赋值,在该算法中,对的信号函数只需实现为一维表格,其开比以前的信号函数你 给出了在保证错误检测延迟一定的条件下进上步降低开销的方法,该函数 相似文献
968.
969.
Visual Speech Synthesis by Morphing Visemes 总被引:6,自引:0,他引:6
We present MikeTalk, a text-to-audiovisual speech synthesizer which converts input text into an audiovisual speech stream. MikeTalk is built using visemes, which are a small set of images spanning a large range of mouth shapes. The visemes are acquired from a recorded visual corpus of a human subject which is specifically designed to elicit one instantiation of each viseme. Using optical flow methods, correspondence from every viseme to every other viseme is computed automatically. By morphing along this correspondence, a smooth transition between viseme images may be generated. A complete visual utterance is constructed by concatenating viseme transitions. Finally, phoneme and timing information extracted from a text-to-speech synthesizer is exploited to determine which viseme transitions to use, and the rate at which the morphing process should occur. In this manner, we are able to synchronize the visual speech stream with the audio speech stream, and hence give the impression of a photorealistic talking face. 相似文献
970.
A concept for a future integer arithmetic unit suitable for a realization with 3-D optoelectronic very large scale integrated (VLSI) circuits is presented. Due to the use of optical interconnections running vertically to the circuit's surface no pin limitation is given. This allows massively parallelism and a higher throughput performance than in all-electronic solutions. To exploit the potential of optical interconnections in VLSI systems efficiently well-adapted low-level algorithms and architectures have to be developed. This is demonstrated for a pipelined arithmetic unit using a redundant number representation. A transistor layout for the optoelectronic circuits is given as well as a specification for the necessary optical interconnection scheme linking the circuits with free-space optics. It is shown that the throughput can be increased by a factor of 10 to 50 compared to current all-electronic processors by considering state-of-the-art optical and optoelectronic technology. Furthermore we present results we gained by investigations on a first realized optoelectronic VLSI test chip. 相似文献