一种基于循环平稳的MPSK信号调制分类改进算法

给出了一种基于循环平稳的MPSK信号调制分类改进算法.通过对预处理后的MPSK信号进行循环平稳分析,把利用高阶累积量对复基带MPSK信号的调制分类推广到已调信号.这种在高阶循环累积量域构成的分类特征不变量具有良好的抗平稳噪声的能力.通过利用二阶循环累量对码元速率的估计,大大减少了累积量估计的运算量.仿真表明,改进后的算法运算精度与原算法大致相当,运算量大大减少.     

An optimal distributed routing algorithm

A distributed optimal one-level routing algorithm is presented. The algorithm is based on Newton's method. Using the variable reduction method, the Hessian matrix becomes diagonal. An example shows that the algorithm has a much faster convergence rate, more accurate results, and better transient behavior than previous work. The algorithm is shown to be convergent, stable, robust, and loop free     

An optimal vector-network-analyzer calibration algorithm

We present an iterative algorithm for calibrating vector network analyzers based on orthogonal distance regression. The algorithm features a robust, yet efficient, search algorithm, an error analysis that includes both random and systematic errors, a full covariance matrix relating calibration and measurement errors, 95% coverage factors, and an easy-to-use user interface that supports a wide variety of calibration standards. We also discuss evidence that the algorithm outperforms the MultiCal software package in the presence of measurement errors and accurately estimates the uncertainty of its results.     

四边形分类识别算法

四边形的分类识别是图形识别中的重要内容.Hough变换是检测直线的基本工具,利用Hough变换检测出图像中各直线与x轴正方向所形成的夹角,对这些夹角降序排序后再进行比较,从而确定四边形的类型.实验结果表明,算法简单有效,能对复杂图像中的四边形进行分类识别,具有一定的实用价值.     

An optimal algorithm for cycle breaking in directed graphs

This paper describes an exact algorithm for the identification of a minimal feedback vertex set in digital circuits. The proposed algorithm makes use of graph reduction and efficient graph partitioning methods based on local properties of digital circuits. It has been implemented and applied to ISCAS-89 benchmark circuits. Previously, non-optimum solutions were found. In other cases, the optimality of the solution could not be established for all circuits. By using the proposed algorithm we obtained the optimum results for all the circuits in a relatively short CPU time.Supported in part by the Technion fund for the promotion of research.     

WDM光网络中固定路由的优化算法

通过研究WDM光网络中固定路由策略的选取对网络性能的影响，提出了一种新的用于优化固定路由的算法-综合代价法。该算法综合考虑了链路负载和路由跳数这两个因素，以综合代价为策略进行路由优化。计算机仿真结果表明，针对不同的网络负载情况，综合代价法能够有效地降低网络的阻塞率，提高网络的性能。     

An efficient algorithm for constructing nearly optimal prefix codes

A new algorithm is presented for constructing nearly optimal prefix codes in the case of unequal letter costs and unequal probabilities. A bound on the maximal deviation from the optimum is derived and numerical examples are given. The algorithm has running timeO(t cdot n), wheretis the number of letters andnis the number of probabilities.     

An improved LBP algorithm for texture and face classification

Local Binary Pattern (LBP) has achieved great success in texture classification due to its accuracy and efficiency. Traditional LBP method encodes local features by binarying the difference in local neighborhood and then represents a given image using the histogram of the binary patterns. However, it ignores the directional statistical information. In this paper, some directional statistical features—including the mean and standard deviation of the local absolute difference—are integrated into the feature extraction to improve the classification ability of the extracted features. In order to reduce estimation errors of the local absolute difference, we further utilize the least square estimate technique to optimize the weight and minimize the local absolute difference, which leads to more stable directional features. In addition, a novel rotation invariant texture classification approach is presented. Experimental results on several texture and face datasets show that the proposed approach significantly improves the classification accuracy of the traditional LBP.     

An exact algorithm for optimal MAE stack filter design.

We propose a new algorithm for optimal MAE stack filter design. It is based on three main ingredients. First, we show that the dual of the integer programming formulation of the filter design problem is a minimum cost network flow problem. Next, we present a decomposition principle that can be used to break this dual problem into smaller subproblems. Finally, we propose a specialization of the network Simplex algorithm based on column generation to solve these smaller subproblems. Using our method, we were able to efficiently solve instances of the filter problem with window size up to 25 pixels. To the best of our knowledge, this is the largest dimension for which this problem was ever solved exactly.     

一种面向多业务恢复的路由优化算法

讨论了在WDM光传送网中完成多业务恢复时所出现的恢复路由资源竞争问题，并提出了一种基于遗传算法的面向多业务恢复的路由优化算法。该算法可以有效地解决恢复路由资源竞争问题，得到全局最优恢复路由。通过对实际网络的计算，验证了该算法在解决多业务恢复路由优化问题上所具备的优势。     

An optimal scheduling algorithm for testing interconnect using boundary scan

Systems will soon be built with ICs that conform with the IEEE 1149.1 boundary scan architecture. Due to the hierarchical nature of such systems, they may contain many boundary scan chains. These chains can be used to test the system, subsystem, and board interconnect. To reduce test time, the application of test vectors to these scan chains must be carefully scheduled. This article deals with problems related to finding an optimal schedule for testing interconnect. This problem is modeled using a directed graph. The following results are obtained: (1) upper and lower bounds on interconnect test time; (2) necessary and sufficient conditions for obtaining an optimal schedule when the graph is acyclic; (3) sufficient condition for obtaining an optimal schedule when the graph is cyclic; and (4) an algorithm for constructing an optimal schedule for any graph.This work was supported by Defense Advanced Research Projects Agency and monitored by the Office of Naval Research under contract No. N00014-87-K-0861. The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the Defense Advanced Research Projects Agency or the U.S. Government.     

OOFDM系统恒定吞吐量自适应调制算法

在光通信系统中,光纤对系统性能影响较大.为了减小多模光纤的色散对光正交频分复用(00FDM)系统性能的影响,阐述了一种新的基于恒定吞吐量的自适应调制算法,改进的算法与原始的恒定吞吐量的自适应调制算法相比,在系统误码率变化不大的情况下,算法的复杂度降低了,仿真结果证明改进算法是正确可行的.     

一种基于WDM光网络的静态波长路由优化算法

研究了WDM光网络中的静态波长路由问题,基于负载的均衡可以改善网络的性能这一事实,提出了一种优化的路由算法(O-Spread算法),文中进行了算法仿真,结果表明优化算法与传统的最短路由算法相比,能够有效地减小网络对于波长数目的需求。     

An automatic control algorithm for the optimal driving of theventricular-assist device

This paper presents a new method of keeping one of the most suitable driving conditions for regulating the outflow volume from the ventricular-assist device (VAD). The experimental results from a mock circulatory system have shown that the relationship between the stroke volume and the systolic duration of the VAD can be specified by the combination of characteristic curves of the positive and negative drive pressures. The optimal operating point on the characteristic curve have been defined as the point at which thrombosis on the blood-contacting surface and hemolysis due to mechanical damage can be avoided and at which the driving energy can be minimized. The present analysis has been revealed that the optimal operating point is the vertex of the triangular figure obtained from the characteristic curve. The algorithms for keeping the optimal operating point and for regulating the stroke volume have been also proposed.     

An adaptive modulation algorithm for performance improvement of MIMO ML systems

In this letter, we propose a simplified adaptive modulation algorithm for a multiple input multiple output (MIMO) system with a maximum likelihood (ML) receiver to minimize BER under a fixed data rate. The proposed algorithm has the advantages of good system performance and low computational complexity, when compared to previous algorithms.     

基于改进花授粉算法的无人船空间全局优化

在分析无人船的空间路径规划的数学建模基础上,提出基于粒子群局部搜索算法策略和维度改进算法策略的改进花授粉(IFPA)的全局搜索优化算法。该算法在水面中解决无人船(US)路径规划问题中,可以加快全局收敛速度,同时保留标准花授粉算法(FPA)的强鲁棒性。实验结果表明:相比其他9种基于群体的算法,IFPA方法对解决US在水面路径规划更为有效。     

An optimal time multiplication free algorithm for edge detection on a mesh

This paper demonstrates an optimal time, fully systolic algorithm for edge detection on a mesh connected processor array. It uses only inexpensive addition and comparison operations which makes it ideal for fine grained parallelism in VLSI. Given anN xN image in the form of a two-dimensional array of pixels, our algorithm computes the Sobel and Laplacian operators for skimming lines in the image and then generates the Hough array using thresholding. The Hough transforms forM different angles of projection are obtained in a fully systolic manner inO(M+N) time, which is asymptotically optimal. In comparison, a previously published multiplication free algorithm has a time complexity ofO(NM). An implementation of our algorithm on a mesh connected finegrained processor array is discussed, which computes at the rate of approximately 170,000 Hough transforms per second using a 50 MHz clock.This research was partially supported by National Science Foundation under Grant No. MIP 8902636     

An algorithm for optimal prefix parsing of a noiseless and memoryless channel

We discuss the prefix encoding of aQ-ary source(Q geq 2)into anL-symbol channel alphabet withL geq Q. We present an optimal encoding scheme that minimizes the expected cost per symbol in the case of equally probable source symbols and arbitrary channel symbol costs.     

基于分类思想的改进粒子群优化算法

针对粒子群算法存在收敛速度慢、收敛精度低且易收敛到局部极值的问题,提出一种基于分类思想的粒子群改进算法。该算法将粒子适度值和适度值均值做差与适度值标准差进行比较,从而将粒子所在区域划分为拒绝域、亲近域、合理域。根据不同区域中粒子的特点选取不同惯性权重和学习因子,使粒子高效地选择自身经验或种群经验,合理增强或减弱粒子全局搜索能力和局部搜索能力。数值实验结果表明,与其他粒子群改进算法相比,新的分类粒子群算法有效加快了粒子的收敛速度,提高了算法的收敛精度,有效改善了算法寻优性能。     

An optimal algorithm for searching a noiselike signal with the minimum frequency-shift keying

An optimal algorithm for seeking a noiselike signal with the minimum frequency-shift keying is synthesized. The algorithm involves estimation of the signal delay time. The noise immunity of quasi-optimal algorithms is analyzed. The proposed algorithms are recommended for application in correlation receivers of noiselike signals with the minimum frequency-shift keying.