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1.
在Booth算法的基础上,结合MIPS 4KC微处理器中的流水线结构和乘法器的工作过程,提出了一种改进的Booth乘法器的设计方法,并采用全制定方法实现,用这种方法实现的乘法器单元具有面积小、单元电路可重复性好、版图设计工作量小、功耗低等特点.  相似文献   
2.
An active set truncated-Newton algorithm (ASTNA) is proposed to solve the large-scale bound constrained sub-problems. The global convergence of the algorithm is obtained and two groups of numerical experiments are made for the various large-scale problems of varying size. The comparison results between ASTNA and the subspace limited memory quasi-Newton algorithm and between the modified augmented Lagrange multiplier methods combined with ASTNA and the modified barrier function method show the stability and effectiveness of ASTNA for simultaneous optimization of distillation column.  相似文献   
3.
In this paper we have studied the control of linear systems with algebraic-equation constraint. A pole-assignment controller with two-layer structure for such constrained systems has been presented. The objective of the controller is to assign the desired poles to constrained system and simultaneously force the corresponding closed-loop system to satisfy the constraint. The conditions for the existence of pole-assignment controller are discussed in different cases. The implementation algorithm of pole-assignment controller is also presented. An example is given to illustrate the validity of the method in this paper.  相似文献   
4.
A discrete dynode electron multiplier with radial flux of electrons was built and tested in the range of low‐voltage scanning electron microscopy as a backscattered electron detector of topographic contrast. The multiplier collects backscattered electron emitted in a specific range of take‐off angles and over the whole azimuth angular range enabling large solid collection angle. Multipliers with different dynode shapes were studied theoretically with the use of the software for particle optics and three assemblies were built and tested experimentally. The gain estimation, assessment of the type of detected electrons (secondary electron or backscattered electron), imaging the spatial collection efficiency and signal‐to‐noise measurements were performed.  相似文献   
5.
钢结构稳定设计——理论与实践   总被引:2,自引:0,他引:2  
本文提出了实际工程结构的非线性理论设计和分析方法(NIDA),并以澳门回归纪念馆的设计为例,展示了本方法的优越性.在设计过程中,设计者无需假设K系数和有效长度,在结构分析完成后便可迅速完成设计,因此本文提出的方法既经济又便利.尽管对于钢框架在往复荷载及动力荷载作用下的弹塑性大位移分析已经非常成熟,但本文的方法开创了结构的非线性分析及设计的新纪元,能够对现行的设计方法理论起到巨大的推动作用.  相似文献   
6.
本文论述了寄生电容不敏感型开关电容四象限模拟乘法器的设计,并提出了一种新型的电路结构,分析了它的性能,以及元器件的非理想特性对其性能的影响和采取的补偿方法。  相似文献   
7.
This letter presents a general analysis of time jitter in sigma-delta synthesizer. One of the practical applications of 1-bit sigma-delta systems is a generation of high-resolution local oscillator (LO) signals. In order to generate LO signals, one may use a single-bit sigma-delta technique to encode sine waves. Today, direct generation of high-frequency sine wave using a clock with higher frequency, is possible. In this letter, we will analyze different LO signal generators and develop a practical way of computation to decide how to choose the best configuration under minimum degradation of signal-to-noise ratio (SNR) at the output.  相似文献   
8.
In this paper, the methods of time series for nonlinearity are briefly surveyed, with particular attention paid to a new test design based on a neural network specification. The proposed integrated expert system contains two main components: an identification environment and a robust forecasting design. The identification environment can be viewed as a integrated dynamic design in which cognitive capabilities arise as a direct consequence of their self-organizational properties. The integrated framework used for discussing the similarities and differences in the nonlinear time series behavior is presented. Moreover, its performance in prediction proves to be superior than the former work. For the investigation of robust forecasting, we perform a simulation study to demonstrate the applicability and the forecasting performance.  相似文献   
9.
针对基于分布的中文词表示构造过程中的参数选择问题进行了系统性的研究。选择了六种参数进行对比实验,在中文语义相似度任务上对不同参数设置下得到的中文词表示的质量进行了评估。实验结果表明,通过选择合适的参数,基于分布的词表示在中文语义相似度任务上能够得到较高的性能,而且,这种高维的词分布表示的质量甚至优于目前流行的基于神经网络(Skip-gram)或矩阵分解(GloVe)得到的低维的词表示。  相似文献   
10.
In this paper, we consider the issue of computing low rank (LR) recovery of matrices with sparse errors. Based on the success of low rank matrix recovery in statistical learning, computer vision and signal processing, a novel low rank matrix recovery algorithm with Fisher discrimination regularization (FDLR) is proposed. Standard low rank matrix recovery algorithm decomposes the original matrix into a set of representative basis with a corresponding sparse error for modeling the raw data. Motivated by the Fisher criterion, the proposed FDLR executes low rank matrix recovery in a supervised manner, i.e., taking the with-class scatter and between-class scatter into account when the whole label information are available. The paper shows that the formulated model can be solved by the augmented Lagrange multipliers and provides additional discriminating power over the standard low rank recovery models. The representative bases learned by the proposed method are encouraged to be closer within the same class, and as far as possible between different classes. Meanwhile, the sparse error recovered by FDLR is not discarded as usual, but treated as a feedback in the following classification tasks. Numerical simulations demonstrate that the proposed algorithm achieves the state of the art results.  相似文献   
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