Signal shaper with a distributed delay: Spectral analysis and design

Input shapers with time delays have proved useful in many applications related to controls for various oscillatory devices, for example flexible manipulators and cranes. In the paper, a novel approach for designing a zero-vibration signal shaper based on equally distributed delay is proposed. The parameter assessment of the shaper is based on the spectral approach. Various characteristics of the shaper are analyzed and compared with the classical zero-vibration shaper with a lumped delay. The analysis shows that the novel shaper is a slower, but more robust alternative to the classical shaper. Besides, the discrete implementation of the shaper is proposed and tested. It includes zero placement based parameter adjustment with the objective to preserve full compensation of the oscillatory mode by the discrete algorithm.     

一种鉴相型感应同步器数显表信号处理方法

论述应用inte18254实现鉴相型感应同步器数显表信号处理的方法,利用计数器可编程的特点实现分辨率可调等功能.     

On distributed order integrator/differentiator

In this paper, we derive the impulse response of the distributed order integrator/differentiator and its asymptotic property by using the complex path integral. Based on the derived analytical impulse response, we present a technique to perform the discretization of the above distributed order integrator/differentiator. The derived asymptotic property can be applied to verify the feasibility of this method. Some new features of the distributed order integrator/differentiator are shown in time and frequency domains. A number of illustrated figures are presented to validate the concepts.     

A dual-threshold up-down counter for GPS acquisition

In this work, the up-down counter detector for the acquisition of GPS signals is modified to use dual-thresholds for each trial. Closed form expressions for the mean and variance of the dwell time and the probabilities of detection and false alarm are derived. The new detector has a significantly smaller mean dwell time than the conventional single-threshold up-down counter and a lower dwell time variance when signals are weak. Further, the new detector has a low computational load, when compared to the optimal sequential probability ratio test (SPRT), whose main disadvantage is its computational complexity.     

Criterion for signal extraction in underdetermined mixtures of bounded support

This work studies the problem of recovering a complex signal (source) from an underdetermined linear mixture of bounded sources. We assume some a priori information of the desired signal in the form of a training sequence and complete absence of knowledge from the other sources, except for their bounded character. The main contribution of this letter is the proposal of a bounded component analysis of the training error that tries to condense the relevant information of the observations in a linear estimate of the desired signal. This subspace can be later used for subsequent refined estimation of the signal of interest. Simulations corroborate the good performance of the proposed method in high SNR scenarios.     

Solving problems: How can guidance concerning task-relevancy be provided?

The analysis of eye movements of people working on problem solving tasks has enabled a more thorough understanding than would have been possible with a traditional analysis of cognitive behavior. Recent studies report that influencing ‘where we look’ can affect task performance. However, some of the studies that reported these results have shortcomings, namely, it is unclear whether the reported effects are the result of ‘attention guidance’ or an effect of highlighting display elements alone; second, the selection of the highlighted display elements was based on subjective methods which could have introduced bias. In the study reported here, two experiments are described that attempt to address these shortcomings. Experiment 1 investigates the relative contribution of each display element to successful task realization and does so with an objective analysis method, namely signal detection analysis. Experiment 2 examines whether any performance effects of highlighting are due to foregrounding intrinsic task-relevant aspects or whether they are a result of the act of highlighting in itself. Results show that the chosen objective method is effective and that highlighting the display element thus identified improves task performance significantly. These findings are not an effect of the highlighting per se and thus indicate that the highlighted element is conveying task-relevant information. These findings improve on previous results as the objective selection and analysis methods reduce potential bias and provide a more reliable input to the design and provision of computer-based problem solving support.     

一种新的基于图像识别技术的信号灯识别算法

将远程数字视频监控和图像识别技术引入武器系统的测试过程中。信号灯作为武器系统测试中最常见的识别对象，多在灰度空间和RGB颜色空间中进行识别，但该两种方法均存在一定不足。鉴于HSI颜色模型在图像信息描述中的优越性，引入HSI空间颜色对比相似距离，用以改善信号灯的识别效果。新算法在RGB空间中进行均值的求解，再转化为HSI颜色，可以减小计算量，提高效率。实验表明，新算法实用性强，有效性高。     

GSM通讯模块在核信号遥测中的应用

论文提出了一种基于GSM通讯模块的新型核信号遥测系统,它实现了非接触、分布式测量和主机统一数据处理等功能的一体化.投放式的探测器作为下位机通过GSM模块将信息发送到监控中心的GSM模块并最终传入PC机作数据处理.系统的数据传输部分已在实验室实现,研究成熟后将不仅在核信号遥测领域内有广泛的应用,在有毒、高辐射或浓烟等恶劣的事故现场也可发挥作用.     

SIMULATION OF CHOPPER FED D. C. MOTOR DRIVE SYSTEM-PROBLEM ORIENTED APPROACH

ABSTRACT

The purpose of this article is to develop an efficient simulation program for the steady state performance of a chopper fed separately excited D.C. motor drive system. The effectiveness of this method lies in the evaluation of the initial state vector of a state equation representing chopper-electromechanical system without passing through the transient region. Effects of source impedance, chopper circuit configuration/parameters have been discussed in detail to prove the generality of this simulation approach.