Flatness-Based Control of a Single Qubit Gate

This work considers the open-loop control problem of steering a two-level quantum system from any initial to any final condition. The model of this system evolves on the state space , having two inputs that correspond to the complex amplitude of a resonant laser field. A symmetry preserving flat output is constructed using a fully geometric construction and quaternion computations. Simulation results of this flatness-based open-loop control are provided.     

基于指数门限的语音端点检测方法

提出了一种基于指数门限（ET）的端点检测方法.ET法为短时能量的概密函数（PDF）建立起统一的语音和噪声模型,根据当前语音数据的信噪比估计出最优的检测门限,并给出了最优检测门限的指数型公式.在“八六三”大词汇量连续语音数据库上的实验结果表明,ET法具有较好的检测性能,在噪声环境中表现出较好的稳健性,信噪比为0 dB时,检测正确率可达89.5%.在信噪比为0～15dB时,检测正确率要明显高于基本能量法、对数能量聚类法（LEC）以及χ2法等语音检测（VAD）方法.     

Guaranteed Parameter Set Estimation for Exponential Sums: The Three-Terms Case

In this paper the problem of parameter estimation for exponential sums with three terms is considered. This task consists of finding the set of parameters (amplitudes as well as decay constants) such that the exponential sum attains values in specified intervals at prescribed time data points. These intervals represent uncertainties in the measurements. An interval variant of Prony’s method is given by which intervals can be found containing all the consistent values of the respective parameters. By the use of interval arithmetic these enclosures can also be guaranteed in the presence of rounding errors. Support from the Ministry of Education and Research of the Federal Republic of Germany under contract no. 1705803 and from the DAAD program PROCOPE under contract no. D/0205730 is gratefully acknowledged.     

On Cosets of Weight 4 of Binary BCH Codes with Minimum Distance 8 and Exponential Sums

We study coset weight distributions of binary primitive (narrow-sense) BCH codes of length n = 2 ^m (m odd) with minimum distance 8. In the previous paper [1], we described coset weight distributions of such codes for cosets of weight j = 1, 2, 3, 5, 6. Here we obtain exact expressions for the number of codewords of weight 4 in terms of exponential sums of three types, in particular, cubic sums and Kloosterman sums. This allows us to find the coset distribution of binary primitive (narrow-sense) BCH codes with minimum distance 8 and also to obtain some new results on Kloosterman sums over finite fields of characteristic 2.     

An Exponential Lower Bound for the Size of Monotone Real Circuits

We prove a lower bound, exponential in the eighth root of the input length, on the size of monotone arithmetic circuits that solve an NP problem related to clique detection. The result is more general than the famous lower bound of Razborov and Andreev, because the gates of the circuit are allowed to compute arbitrary monotone binary real-valued functions (including AND and OR). Our proof is relatively simple and direct and uses the method of counting bottlenecks. The generalization was proved independently by Pudlák using a different method, who also showed that the result can be used to obtain an exponential lower bound on the size of unrestricted cutting plane proofs in the propositional calculus.     

结合自适应分割策略的图像去雾算法

暗通道先验去雾算法处理图像易出现局部失真问题,针对这一现象,提出一种单幅户外图像去雾算法。首先,利用四叉树分解的方法得到准确的大气光估计值;然后,结合暗通道图像的直方图分布特征,利用最大化类间方差策略自适应的估计暗通道图像分割阈值,并以此为先验知识优化透射率;最后,使用Gamma矫正提升图像整体对比度。实验表明,该算法能够有效地避免暗通道先验算法在天空区域失真的问题,对比其他算法,恢复图像视觉效果良好,客观评价指标均有所提升。     

模糊聚类与SVM诊断模拟电路单软故障的方法

针对低可测性模拟电路中存在的模糊组问题,提出一种模拟电路单个软故障诊断的方法．该方法对被测电路的故障进行模糊聚类,根据聚类的有效性指标自适应确定聚类数,并利用聚类的信息来确定可测元件集,引入支持向量机对故障进行分类识别．支持向量机结构简单、泛化能力强．最后,以模拟和混合信号测试标准电路证实了文中方法的有效性．     

利用单片机门控位测量脉冲的宽度

介绍一种利用单片机的门控位扩展测量脉冲宽度的软件方法.     

Threshold counters with increments and decrements

A threshold counter is a shared data structure that assumes integer values. It provides two operations: changes the current counter value from v to v+1, while returns the value v/w, where v is the current counter value and w is a fixed constant. Thus, the operation returns the “approximate” value of the counter to within the constant w. Threshold counters have many potential uses, including software barrier synchronization. Threshold networks are a class of distributed data structures that can be used to construct highly-concurrent, low-contention implementations of shared threshold counters. In this paper, we give the first proof that any threshold network construction of a threshold counter can be extended to support a operation that changes the counter value from v to v−1.     

Exponential stability of a class of nonlinear dynamical systems with uncertainties

Exponential stability for a class of nonlinear dynamical systems with uncertainties is investigated. Based on the stability of the nominal systems, a new approach to synthesizing a class of continuous state feedback controllers for uncertain nonlinear dynamical systems is proposed. By such a class of feedback controllers, we can guarantee exponential stability of uncertain nonlinear dynamical systems. Our approach can give a clear insight into system analysis. Finally, an illustrative example is given to demonstrate the utilization of the approach developed in this paper.     

Exponential stability of a mono-tubular heat exchanger equation with output feedback

This paper is concerned with stability analysis of a mono-tubular heat exchanger equation with static output feedback. The mono-tubular heat exchanger equation is exponentially stable when the input variable is identically zero. In this paper, it is shown that the C₀-semigroup generated by the closed-loop operator consisting of the mono-tubular heat exchanger equation and the output feedback law satisfies the spectrum determined growth assumption.     

基因电路研究综述

基因网络相关的研究是生物信息学的重要研究领域．基因电路方法是目前基因网络研究的一种重要方法，本文从以下角度介绍基因电路研究的进展情况及相关研究成果；构成基因电路的基本模块；基因电路的设计与实现；人工基因电路的应用．     

EWB软件在电子电路中的应用

介绍了Electronics Workbench(EWB）软件的功能与特点,通过实例说明了该软件的使用方法。     

Implementing Qubits with Superconducting Integrated Circuits

Superconducting qubits are solid state electrical circuits fabricated using techniques borrowed from conventional integrated circuits. They are based on the Josephson tunnel junction, the only non-dissipative, strongly non-linear circuit element available at low temperature. In contrast to microscopic entities such as spins or atoms, they tend to be well coupled to other circuits, which make them appealling from the point of view of readout and gate implementation. Very recently, new designs of superconducting qubits based on multi-junction circuits have solved the problem of isolation from unwanted extrinsic electromagnetic perturbations. We discuss in this review how qubit decoherence is affected by the intrinsic noise of the junction and what can be done to improve it. PACS: 03.67.-a, 03.65.Yz, 85.25.-j, 85.35.Gv     

Single lens stereo with a plenoptic camera

Ordinary cameras gather light across the area of their lens aperture, and the light striking a given subregion of the aperture is structured somewhat differently than the light striking an adjacent subregion. By analyzing this optical structure, one can infer the depths of the objects in the scene, i.e. one can achieve single lens stereo. The authors describe a camera for performing this analysis. It incorporates a single main lens along with a lenticular array placed at the sensor plane. The resulting plenoptic camera provides information about how the scene would look when viewed from a continuum of possible viewpoints bounded by the main lens aperture. Deriving depth information is simpler than in a binocular stereo system because the correspondence problem is minimized. The camera extracts information about both horizontal and vertical parallax, which improves the reliability of the depth estimates     

Zeros and Local Extrema of Trigonometric Sums

Theorems on the number of zeros and number of local extrema of trigonometric sums, in particular, Gauss and Weyl sums, are proved.     

Exponential synchronization of a class of neural networks with time-varying delays.

This paper aims to present a synchronization scheme for a class of delayed neural networks, which covers the Hopfield neural networks and cellular neural networks with time-varying delays. A feedback control gain matrix is derived to achieve the exponential synchronization of the drive-response structure of neural networks by using the Lyapunov stability theory, and its exponential synchronization condition can be verified if a certain Hamiltonian matrix with no eigenvalues on the imaginary axis. This condition can avoid solving an algebraic Riccati equation. Both the cellular neural networks and Hopfield neural networks with time-varying delays are given as examples for illustration.     

Preconditioning the Matrix Exponential Operator with Applications

The idea of preconditioning is usually associated with solution techniques for solving linear systems or eigenvalue problems. It refers to a general method by which the original system is transformed into one which admits the same solution but which is easier to solve. Following this principle we consider in this paper techniques for preconditioning the matrix exponential operator, e ^A y ₀, using different approximations of the matrix A. These techniques are based on using generalized Runge Kutta type methods. Preconditioners based on the sparsity structure of the matrix, such as diagonal, block diagonal, and least-squares tensor sum approximations are presented. Numerical experiments are reported to compare the quality of the schemes introduced.     

Functional Estimation with Respect to a Threshold Parameter via Dynamic Split-and-Merge

We consider a class of stochastic models for which the performance measure is defined as a mathematical expectation that depends on a parameter , say (), and we are interested in constructing estimators of in functional form (i.e., entire functions of ), which can be computed from a single simulation experiment. We focus on the case where is a continuous parameter, and also consider estimation of the derivative (). One approach for doing that, when is a parameter of the probability law that governs the system, is based on the use of likelihood ratios and score functions. In this paper, we study a different approach, called split-and-merge, for the case where is a threshold parameter. This approach can be viewed as a practical way of running parallel simulations at an infinite number of values of , with common random numbers. We give several examples showing how different kinds of parameters such as the arrival rate in a queue, the probability that an arriving customer be of a given type, a scale parameter of a service time distribution, and so on, can be turned into threshold parameters. We also discuss implementation issues.