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151.
Distinctive features of architectural-structural organization and use of memory networks are considered with the aim of choosing an optimal configuration in designing distributed computer systems.  相似文献   
152.
Biological and technological systems process information by means of cascades of signals. Be they interacting genes, spiking neurons or electronic transistors, information travels across these systems, producing, for each set of external conditions, an appropriate response. In technology, circuits performing specific complex tasks are designed by humans. In biology, however, design has to be ruled out, confronting us with the question of how these systems could have arisen by accumulation of small changes. The key factor is the genotype-phenotype map. With the exception of RNA folding, not much is known about the exact nature of this mapping. Here, we show that structure of the genotype-phenotype map of simple feed-forward circuits is very close to the ones found in RNA; they have a large degree of neutrality, by which a circuit can be completely rewired keeping its input-output function intact, and there is a relatively small neighbourhood of a given circuit containing almost all the phenotypes.  相似文献   
153.
Passivity Analysis of Dynamic Neural Networks with Different Time-scales   总被引:1,自引:0,他引:1  
Dynamic neural networks with different time-scales include the aspects of fast and slow phenomenons. Some applications require that the equilibrium points of the designed networks are stable. In this paper, the passivity-based approach is used to derive stability conditions for dynamic neural networks with different time-scales. Several stability properties, such as passivity, asymptotic stability, input-to-state stability and bounded input bounded output stability, are guaranteed in certain senses. A numerical example is also given to demonstrate the effectiveness of the theoretical results.  相似文献   
154.
智能化空调设计负荷计算软件的开发   总被引:1,自引:0,他引:1  
为了解决目前已有空调负荷计算软件使用效率低,不符合设计人员思维习惯的弊病,本文将基于神经网络的专家系统技术与空调负荷“指标估算法”结合起来,开发了一套智能化空调负荷计算软件,对空调设计负荷计算的智能化进行了有益的尝试。该软件计算结果准确,特别适合于经验不足的设计人员使用。  相似文献   
155.
Broadcasting is the process of spreading one piece of information among a group of individuals connected by an interconnection network. In this paper we give exact lower and upper bounds for the number of broadcast schemes in arbitrary networks. Also, we give the exact value for complete bipartite graphs and an upper bound for regular networks. Based on the counting method we describe a new random algorithm for broadcasting in networks.  相似文献   
156.
In a previous work, convective heating of carbon dioxide was studied with neural networks (NN), obtaining a totally heuristical heat transfer equation from the direct regression of experimental data. In the present work, the analysis focuses on the cooling process, which has a technical relevance in various applications, as for example in transcritical refrigeration cycles. Heat transfer around the critical zone presents a marked enhancement, that follows the peaks in thermophysical properties like thermal conductivity and heat capacity. Similarly, other properties like density and enthalpy, present a strong variation in narrow temperature intervals around the critical point.This constitutes then a highly non-linear phenomenon, for which it is advisable to use a very flexible function approximator like the NNs. NN models were applied both in terms of dimensionless numbers and of physical quantities, obtaining the two corresponding NN architectures. The choice of the optimal number of neurons in the NN hidden layer is discussed. The NN models are then compared with a recent correlation from literature, for which the validation results present an AAD of 27% and a bias of −26% with an evident prediction shifting. On the other hand the NN models in terms of dimensionless numbers and of physical quantities have AAD and bias of 14% and −4%, and of 7% and −2%, respectively, showing a largely better performance.  相似文献   
157.
The theory of planned behavior suggests attitudes are a product of salient beliefs. This study examined whether aggregating salient beliefs was plausible within a more biologically centered information-processing environment. A neural network was used to examine associations among beliefs relating to exercise intention. Data on intentions and behavioral, normative, and control beliefs from 114 respondents were used to train (by error backpropagation) a neural network to associate beliefs with intention. The R2 between the network's estimated and self-reported intention was .66. The network's representation comprised 6 belief profiles associated with high, moderate, or low behavioral intention. The neural network accommodated complex relationships among beliefs and belief-intention associations and indicated how high-level constructs such as attitudes may be viewed as the best fit (compromise state) between aroused beliefs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
158.
侯透梅  郭洪 《光电工程》1998,25(1):70-72
利用光学衍射原理,研制成了光纤光栅衍射屏,并与计算机神经网络相结合,开发了了一种识别立体形状的视觉系统。本文介绍了光纤光栅的设计原理及计算方法,给出了系统的总体结构及工作原理,完成了三棱 柱,三棱锥、四棱柱,四棱锥和球等立体形状学习与识别,并讨论了实验结果。  相似文献   
159.
本文根据实地考察内容,结合宽带网络技术和业务重点及实施策略,全面介绍了日本关西宽带实验网发展背景,通信与广播电视综合应用实验和B-ISDN实用化实验的进展以及NTT所起作用。文章最后就关西宽带实验网的借鉴意义提出了几方面意见。  相似文献   
160.
萧振华 《世界电信》1998,11(4):17-18
运用接入新技术组建农村用户接入网已势在必行。本文针对我国经济水平低、地区间发展不平衡等实际情况,对组建我国农村用户接入网的有关策略进行了论述。  相似文献   
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