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951.
A. Yu. Dorogov 《Cybernetics and Systems Analysis》2001,37(2):175-181
Structural models of modular neural networks without loops are considered. The notion of a weakly connected network is introduced. A genetic principle of generation of weakly connected neural networks is proposed, and its reproductive power is proved on the basis of the theory of categories. Algorithmic realizations of structural synthesis are considered. Some examples are given. 相似文献
952.
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
953.
A Parametric Texture Model Based on Joint Statistics of Complex Wavelet Coefficients 总被引:27,自引:0,他引:27
We present a universal statistical model for texture images in the context of an overcomplete complex wavelet transform. The model is parameterized by a set of statistics computed on pairs of coefficients corresponding to basis functions at adjacent spatial locations, orientations, and scales. We develop an efficient algorithm for synthesizing random images subject to these constraints, by iteratively projecting onto the set of images satisfying each constraint, and we use this to test the perceptual validity of the model. In particular, we demonstrate the necessity of subgroups of the parameter set by showing examples of texture synthesis that fail when those parameters are removed from the set. We also demonstrate the power of our model by successfully synthesizing examples drawn from a diverse collection of artificial and natural textures. 相似文献
954.
Ca2+和Pb2+与双层类脂膜相互作用的研究 总被引:2,自引:0,他引:2
用电化学方法研究了卵磷脂和氧化胆固醇构成的双层类脂膜与 Ca~(2+)和 Pb~(2+)的相互作用。结果发现:双层类脂膜与含 Ca~(2+)或 Pb~(2+)的溶液接触15分钟后,产生较稳定的膜电位信号并与溶液中 Ca~(2+),Pb~(2+)浓度相关。其作用机制主要是源于静电作用与合作效应,同时,对三种不同存在状态的双层类脂膜的通透性进行了验证,对某些干扰离子和 pH 值的影响进行了研究。 相似文献
955.
一种实体纹理的设计方法和实现 总被引:6,自引:0,他引:6
一个实用的实体纹理系统不仅应用有清晰的模型,还要求纹理的效果丰富,易于扩展和实现,本文在分析实体纹理的概念和计算原理的基础上,给出了一种将实体纹理分三步实现的方案,然后纹理参数进行了分类,给出了一个纹理数据结构的组织方法,最后讨论了这种方案的实际应用。 相似文献
956.
底层相关的VLSI高层次设计策略 总被引:1,自引:1,他引:0
边计年 《计算机辅助设计与图形学学报》2000,12(11):827-829
在VLSI系统设计、行为设计和逻辑设计过程中,未考虑到的与半导体制造工艺有关的因素(如延迟、功耗问题等)严重影响设计结果的性能,以至使物理设计结果的性能远离原来的设计目标,针对这个问题,文中提出与底层有关的VLSI高层次设计策略,将影响性能的底层参数和信息引入高层次设计中,使得高层次设计结果在进行物理实现之时能满足性能要求。 相似文献
957.
An approach to the online synthesis of an optimal effective controller for discrete event systems is presented. The optimal effective controller can achieve the prescribed (cumulative) effectiveness measure while minimizing the total cost incurred for the execution of events. This approach is constructed over a generalized control framework for automata‐based discrete event systems, which allows event enforcement in addition to the (original) event disablement/enablement as the control mechanism. The optimal effective control policy generated by this approach is proved to be the least restrictive among all the possible optimal effective control policies for the given online expansion tree of the system behavior. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
958.
For deaf persons to have ready access to information and communication technologies (ICTs), the latter must be usable in sign
language (SL), i.e., include interlanguage interfaces. Such applications will be accepted by deaf users if they are reliable
and respectful of SL specificities—use of space and iconicity as the structuring principles of the language. Before developing
ICT applications, it is necessary to model these features, both to enable analysis of SL videos and to generate SL messages
by means of signing avatars. This paper presents a signing space model, implemented within a context of automatic analysis
and automatic generation, which are currently under development.
相似文献
Patrice DalleEmail: |
959.
面向财务应用的软件设计课程教学模式 总被引:1,自引:0,他引:1
为了培养既懂财务又懂软件开发技术的复合型人才,根据金融财务类应用的需要,本文提出了一个面向软件课程设计的教学模型。融合计算机基础理论、软件开发技术、软件工程学原理以及CMM软件过程体系,构建了教学模式框架。该模型具有良好的课程总体结构以及动态适应新技术发展的能力,该模型适合财务类院校软件复合性人才培养的需要。 相似文献
960.
Naren Narasimhan Elena Teica Rajesh Radhakrishnan Sriram Govindarajan Ranga Vemuri 《Formal Methods in System Design》2001,19(3):237-273
This paper presents a formal specification and a proof of correctness for the widely-used Force-Directed List Scheduling (FDLS) algorithm for resource-constrained scheduling of data flow graphs in high-level synthesis systems. The proof effort is conducted using a higher-order logic theorem prover. During the proof effort many interesting properties of the FDLS algorithm are discovered. These properties are formally stated and proved in a higher-order logic theorem proving environment. These properties constitute a detailed set of formal assertions and invariants that should hold at various steps in the FDLS algorithm. They are then inserted as programming assertions in the implementation of the FDLS algorithm in a production-strength high-level synthesis system. When turned on, the programming assertions (1) certify whether a specific run of the FDLS algorithm produced correct schedules and, (2) in the event of failure, help discover and isolate programming errors in the FDLS implementation.We present a detailed example and several experiments to demonstrate the effectiveness of these assertions in discovering and isolating errors. Based on this experience, we discuss the role of the formal theorem proving exercise in developing a useful set of assertions for embedding in the scheduler code and argue that in the absence of such a formal proof checking effort, discovering such a useful set of assertions would have been an arduous if not impossible task. 相似文献