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将按单元集成有限元代数方程组换为按结点集成,并利用贮量集中的思想来处理右端项,得到一维最紧凑存贮的有限元方法,使总体矩阵元素紧凑为未知结点数的三倍以下,比矩形网格有限差分法所需存贮单元还要少,程序结构也更简单合理。同时减少了计算量,提高了运算效率,其优越性在解非线性问题时更为明显。 相似文献
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目前的电子计算机适于解决数字运算问题,但是在解决辨别、联想、推理等所谓随机问题方面的能力却远不如人的大脑.企图模仿人脑的解剖结构来设计计算机以解决随机问题,并利用光学的独特功能,这就是光学神经元计算机.据此,Hopfield提出了一种关联存贮模型(或称为内容存贮),即每个存贮状态不是按地址存贮,而是按内容存贮在整个神经网络系统上.光学由于具有内禀的并行性,特别适于实现这个模型.采用纯光学或光电混会方法,通过光学矩阵乘法,取阀值运算,反馈迭代过程,可以实现从有误差的输入信息中提取正确的关联存贮信息.利用全息技术,有可能实现二维数据的关联存贮. 相似文献
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本文提出了一种用菲涅尔全息片实现的IPA(Interpattern Association)型联想存贮器。其对不独立的存贮模式有较强的分辨能力,采用菲涅尔全息片,可以实现大神经元数目的光学联想存储,具有较大的存储能力。 相似文献
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本文给出了P-对称大型疏矩阵方程组的LL^p解法的FORTRAN语言过程,并论述了过程中存贮稀疏矩阵的方法,最后给出了一个算例。 相似文献
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反射式液晶显示光学的理论计算 总被引:5,自引:3,他引:2
本文针对反射式液晶显示模式,在Berreman’s 4×4矩阵和扩展琼斯矩阵的基础上,分别推导了适于金属和介质两种反射镜下的反射式液晶显示光学的理论计算.并模拟了反射式液晶显示在自然光照射下的光电特性、视角光学特性,为反射式液晶显示新模式的开发做了理论上的计算研究. 相似文献
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链烷烃标准熵的拓扑研究 总被引:4,自引:0,他引:4
根据核磁共振的峰数及Randic的碳原子支化度 ,提出了碳原子特征值 .基于连接矩阵和碳原子特征值 ,建立新的连接指数 mY .其中的 0阶连接性指数0 Y很容易计算 ,且对烷烃异构体有很强的区分能力 .将 15 7种气态链烷烃的标准熵与其0 Y相关联 ,R =0 .9985 ,属于优级模型 .与Randic指数的0 χ及倪才华等提出的信息拓扑指数Ix、IW 比较 ,0 Y具有良好的性质相关性与结构选择性 相似文献
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用矩阵条件数求解相移最佳采样方式 总被引:5,自引:2,他引:3
应用相移干涉术测量物体相位时,相移量与相移帧数存在着最佳取值问题,即最佳采样方式,它决定着系统抗扰动和降低误差的能力.用系数矩阵的条件数衡量相位测量误差矩阵与强度探测误差矩阵方程的性态,即光强方程组对扰动的敏感程度,经数学推导及论证,得出结论:当系数矩阵为正交矩阵时,相位计算的误差最小,或者说在等间距满周期采样情况下,具有最强的抗噪音能力.在推导出最佳采样方式后,对系数矩阵的条件数与采样方式之间的关系进行了计算机模拟,并给出了模拟曲线. 相似文献
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Adaptive Clipping for Neural Associative Memories 总被引:1,自引:0,他引:1
CHANG Shengjiang SHEN JinyuanSONG Zhuang ZHANG Yanxin 《Chinese Journal of Lasers》1997,6(4):372-377
AdaptiveClippingforNeuralAsociativeMemoriesCHANGShengjiangSHENJinyuanSONGZhuangZHANGYanxin(InstituteofModernOptics,NankaiUni... 相似文献
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《Fiber and Integrated Optics》2007,26(2):99-110
This paper presents the method of an availability performance analysis that can be used for all-optical networks. We compare different schemes of protection and restoration in a fully connected mesh network based on optical cross-connects, optical fibers, and fiber amplifiers. Specifically treated is an optical mesh network physically mapped onto a Scandinavian backbone. In order to compare different survivability strategies, we selected two nodes located roughly 420 km apart. The goal of this work is to point out possible ways to improve connection availability. A number of survivability schemes are compared, for which the availability model of logical connection is derived and a calculation procedure is described. Our results show that unprotected schemes cannot ascertain reasonably high requirements on connection availability in the backbone network. Thus, if a redundant structure of logical connection is considered, the particular survivability scheme should be evaluated in order to maximize connection availability. 相似文献
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传统网络化测试技术存在网络化测试精准度低、不能对全部数据进行测试、数据属性测试不明确等问题,为此,基于RS485串行连接框图和存储器结构对网络化测试技术展开研究。采用信息融合技术中的信息融合算法得出测试估计误差方阵,完善传统技术中精准度低的问题。利用定义模型和动态模型有限内存的处理技术,对整个存储内存进行访问,从而对全部数据进行测试。采用分布式计算技术,利用二元制算法测试存储器中数据的质量,从而确定数据的属性。通过实验得出结论,本文测试技术不但能够确定数据属性,还能提高网络化测试精准度,并对全部数据进行测试,为我国未来网络化测试技术奠定了坚实的基础。 相似文献
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An optical cross connection network which adopts coarse wavelength division multiplexing (CWDM) and data packet is introduced. It can be used to realize communication between multi-CPU and multi-MEM in parallel computing system. It provides an effective way to upgrade the capability of parallel computer by combining optical wavelength division multiplexing (WDM) and data packet switching technology. CWDM used in network construction, optical cross connection (OXC) based on optical switch arrays, and data packet format used in network construction were analyzed. We have also done the optimizing analysis of the number of optical switches needed in different scales of network in this paper. The architecture of the optical interconnection for 8 wavelength channels and 128 bits parallel transmission has been researched. Finally, a parallel transmission system with 4 nodes, 8 channels per node, has been designed. 相似文献
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利用电子俘获材料实现光学IPA神经网络模型 总被引:3,自引:0,他引:3
报道用自行研制的CaS(Eu,Sm)电子俘获材料表示互联机重矩阵以实现光学IPA神经网络模型,由于CaS(Eu,Sm)的红外激励发光强度与俘获的电子密度及红外读出光强度之积成线性关系,故可用来表示互联权重矩阵以实现光学神经网络,这种互联权重矩阵具有很宽的数值范围,并可以用光学的办法进行快速擦除,重写。 相似文献
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<正>Projective synchronization of a weighted complex network is studied in which nodes are spatiotemporal chaos systems and all nodes are coupled not with the nonlinear terms of the system but through a weighted connection.The range of the linear coefficient matrix of separated configuration,when the synchronization is implemented,is determined according to Lyapunov stability theory.It is found that projective synchronization can be realized for unidirectional star-connection even if the coupling strength between the nodes is a given arbitrary weight value.The Gray-Scott models having spatiotemporal chaos behaviours are taken as nodes in the weighted complex network,and simulation results of spatiotemporal synchronization show the effectiveness of the method. 相似文献
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Atsushi Okamoto Hisashi Matsuoka Motoki Saito Yoshihisa Takayama Mototsugu Takamura 《Optical Review》1999,6(3):189-195
We propose a new optical network device photorefractive connection module (PRCM) which operates as optical switch, amplifier and signal distributor controlled by parallel optical signals. Simple optical control bus systems can be realized by cascade connection of PRCMs. PRCM branches off a desired channel from the spatial multiplexed optical bus line by appropriate setting of the control beam pattern. PRCM uses cross polarized four wave mixing (CPFWM) with extraordinary polarized writing beams and an ordinary polarized reading beam to achieve a high connection gain to the next PRCM stage. We analyze the phase matching angle of CPFWM in which the optical paths of two pump beams are slightly different. The phase conjugate reflectivity indicating a branching ratio of optical signal is derived and calculated in consideration of the phase mismatching Δk. The optimum pump ratio and the grating vector orientation for the largest phase conjugate reflectivity and signal amplification factor are discussed for optical design of PRCM. Since the measured signal beam power after passing through the BaTiO3 crystal is three or four times higher than its incident power, PRCM has a sufficient connection gain for optical bus and interconnection systems. 相似文献
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In an optomechanical resonator, the optical and mechanical excitations can be coherently converted, which induces a transparency window for a weak probe laser beam. Here, we report an experimental study of transient optomechanically induced transparency(OMIT) using the silica microsphere with the breathing modes. The transient OMIT behavior obtained are in good agreement with theoretical calculations. In addition, the coherent interconversion between optical and mechanical excitations that can be used for light storage and readout has also been studied here. Our experimental results indicate that the light storage is closely related to the process of OMIT, and the photon-phonon conversion can be further applied to optical wavelength or optical mode conversion. 相似文献