Real-time flow-based video abstraction using OpenCL

A non-photorealistic rendering technique is a method to show various effects different from those of realistic image generation.Of the various techniques,flow-based image abstraction displays the shape...     

Full-order Luenberger observer based on fuzzy-logic control for sensorless field-oriented control of a single-sided linear induction motor

This paper investigates sensorless indirect field oriented control (IFOC) of SLIM with full-order Luenberger observer. The dynamic equations of SLIM are first elaborated to draw full-order Luenberger observer with some simplifying assumption. The observer gain matrix is derived from conventional procedure so that observer poles are proportional to SLIM poles to ensure the stability of system for wide range of linear speed. The operation of observer is significantly impressed by adaptive scheme. A fuzzy logic control (FLC) is proposed as adaptive scheme to estimate linear speed using speed tuning signal. The parameters of FLC are tuned using an off-line method through chaotic optimization algorithm (COA). The performance of the proposed observer is verified by both numerical simulation and real-time hardware-in-the-loop (HIL) implementation. Moreover, a detailed comparative study among proposed and other speed observers is obtained under different operation conditions.     

一种提高SIFT特征匹配正确率的方法

针对尺度不变特征变换(SIFT)特征匹配算法存在计算量大、实时性差、误匹率高的问题,提出一种基于距离比率准则的方法来去除SIFT特征匹配中的错误匹配。传统的方法是采用随机选取一致性(RANSAC)方法选取出正确的匹配对,但是需要通过反复迭代,复杂、耗时并且仍存有部分误匹配的现象。改进后的方法直接通过两条匹配直线斜率的一致性判断,剔除不在斜率范围内的匹配,此方法算法简单,省时高效,从而较大提高了特征匹配的正确率。实验结果表明,通过采用距离比率准则方法具有较高的匹配精度,同时减少了匹配的时间,使实时性得到提高。     

An extreme learning machine combined with Landweber iteration algorithm for the inverse problem of electrical capacitance tomography

The image reconstruction of the electrical capacitance tomography (ECT) is an ill-posed and sparse problem. In order to increase the accuracy and speed of the image reconstruction, this paper proposes a new reconstruction algorithm which is based on the extreme learning machine (ELM) with the Landweber iteration method. Firstly, a nonlinear mapping model is established between the pixel gray-scale values and the interelectrode capacitances by using the ELM which has a good learning ability and high speed. Secondly, the Landweber iteration method, which has a good performance in convergence and stability, is applied to calculate the output weight matrix of ELM. Finally, a convergence and stable mapping model of ELM with the Landweber iteration algorithm (L-ELM) for ECT image reconstruction is trained on Matlab platform. Both simulation and measurement tests are carried out to evaluate and analyze the proposed method. Experimental results indicate that the proposed algorithm has good generalization ability and high image reconstruction quality which are better than those of conventional ELM algorithm.     

Adaptive MPC based on MIMO ARX-Laguerre model

This paper proposes a method for synthesizing an adaptive predictive controller using a reduced complexity model. This latter is given by the projection of the ARX model on Laguerre bases. The resulting model is entitled MIMO ARX-Laguerre and it is characterized by an easy recursive representation. The adaptive predictive control law is computed based on multi-step-ahead finite-element predictors, identified directly from experimental input/output data. The model is tuned in each iteration by an online identification algorithms of both model parameters and Laguerre poles. The proposed approach avoids time consuming numerical optimization algorithms associated with most common linear predictive control strategies, which makes it suitable for real-time implementation. The method is used to synthesize and test in numerical simulations adaptive predictive controllers for the CSTR process benchmark.     

液压驱动的多冗余机械臂逆运动学算法

液压驱动的多冗余机械臂用常规方法很难实现实时、精确的自动化控制,提出了一种基于几何理论的数值迭代算法,能快速地求解出多冗余机械臂的运动学逆解,并利用此算法对混凝土泵车的臂架系统进行了模拟仿真,仿真结果表明,此算法符合泵车臂架系统的实时自动化控制。     

冗余自由度仿人机械臂自适应迭代学习控制研究

在深入研究自适应迭代学习控制理论、七自由度乒乓球机械臂动力学模型及轨迹规划的基础上,提出将改进后的自适应迭代学习控制算法运用到带有重复时变干扰的冗余自由度机械臂上。该控制系统旨在实现两大目标：一是使乒乓球机械臂准确快速地跟踪参考轨迹并在末点达到指定的击球速度;二是引入饱和函数减小输入转矩的抖振。Lyapunov理论分析及MATLAB仿真验证了整个控制系统的有效性：当迭代次数增加时,跟踪误差关于有限时间区间内一致收敛到零;加快迭代学习的收敛速度,并消除抖振。     

Fault Detection of continuous time linear switched systems using combination of Bond Graph method and switching observer

In this paper, a new Fault Detection (FD) scheme based on combination of switching observer and Bond Graph (BG) method for linear continuous time switched systems with Average Dwell Time (ADT) approach is proposed. The proposed scheme is a BG-based two-stage FD system in which the compact state space representation and Global Analytical Redundancy Relations (GARRs) are derived based on the BG model. In the first stage, a switched observer is designed considering disturbance attenuation level, fault sensitivity and rapid fault detection criteria by solving a weighted Linear Matrix Inequality (LMI) optimization problem. Next, a new form of GARRs which is based on output estimation error of the observer and is called Error-based Global Analytical Redundancy Relations (EGARRs) is developed to combine the observer and BG method. The output estimation errors from the observer, which are adequately sensitive to faults and simultaneously the effects of disturbances are attenuated therein, are given to the EGARRs to generate the residuals of the FD system. The proposed method may be used for fault detection of switched linear systems with ADT based on the BG model of the system. Finally, two case studies including a two-tank system and a buck converter-driven DC motor are considered to show the efficiency and real-time implementation of the proposed method.     

A study on performance of introducing ERP to semiconductor related industries in Taiwan

Enterprise resource planning (ERP) has become critical to enhancing the competitiveness of the semiconductor industry in Taiwan by applying information technology to integrate internal information as well as external service capability of an enterprise to increase the flow speed and values and reduce the costs of human and managerial resources, manufacturing, management, and marketing. The success of ERP implementation depends on several factors, such as space, time, location, industry, and the like. It is critically important to collect information on the successful factors of ERP implementation and evaluate the performance of ERP in semiconductor-related industries in Taiwan. A statistical method based on Parasuraman et al. was applied to ERP implementation by providing a pair of performance indices, i.e., action and importance. In addition, a performance evaluation matrix, originally proposed by Lambert and Sharman, was revised to set up a standard by providing performance upper and lower control limits with the emphases of the Taguchi method and Shewhart control charts. Finally, quality function deployment (QFD) was used to remedy the weaknesses and develop corporate strategies to improve the ERP implementation. The major advantage of this proposed integrated approach is to evaluate the success of the implementation for a new system quickly at low cost. More importantly, by examining action and importance indices, the enterprise can decide how the resources should be deployed effectively and efficiently to further improve the ERP implementation.     

S7-1500与S7-1200在风洞控制系统中的应用

当前,西门子PLC已在风洞控制系统中得到了广泛应用,但新一代的PLC S7-1500与S7-1200并没有很多应用案例。S7-1500 PLC作为西门子新的旗舰产品,性能卓越;S7-1200PLC单机可对4轴进行高速脉冲控制。S7-1500与S7-1200之间通过PROFINET通信,实时性更好,抗干扰性更强。同时,风洞控制系统还采用了西门子的G150变频器和V90伺服系统,使得整个控制系统更加统一。该文通过介绍一个新的风洞控制系统设计方案,介绍了S7-1500与S7-1200以及V90的实际应用,为以后的风洞控制系统设计以及S7-1500与S7-1200的实际应用提供参考。     

An improved stopping condition guarantee recovery of sparse signal via Subspace Pursuit method

The Subspace Pursuit (SP) algorithm is one of greedy pursuit methods which is used to reconstruct of K-sparse signal. Unlike existing condition produced by Dai and Milenkovic in 2004 that suggests the residual value of current iteration is reduced from the previous iteration, our approach eliminates useless information by reducing the number of iterations used to detect the correct support set. This operation is done by suggesting a new halting condition that can capture the best support set which can give the best representation of the reconstructed signal. The new halting conditions enhanced the SP algorithm to low computational complexity and reconstruction accuracy of the sparse signal.A mathematically proven for two halt condition: noiseless setting, and noisy setting for signal affected by Gaussian noise. An error bound relation also is driven.In this paper, we try also to relax the restricted isometry constant RIC value to narrows the gap between the known bounds and ultimate performance, which it produced by Dai.Simulation results show that the new halting condition can overpass best results produce by earlier iteration and rise time consume. Our new halting condition can catch this earlier iteration and enhanced SP algorithm results.     

基于ARM的太阳跟踪装置闭环控制系统设计

文章以跟踪太阳为目的,设计了以ARM7的微处理器LPC2290为硬件,μC/OS-Ⅱ实时操作系统为软件平台的太阳跟踪装置系统。在分析了步进电机和环境影响因素的基础上,提出了加入角度传感器形成闭环控制系统的方案。在LPC2290上实现了μC/OS-Ⅱ实时操作系统的移植,分析了跟踪装置闭环控制系统的任务划分、任务设计。实现了跟踪系统对太阳大范围、高精度的全天候自动跟踪。     

Computing the spectral decomposition of symmetric matrices and the singular value decomposition of nonsymmetric matrices with guaranteed accuracy

A new implementation of the Godunov-inverse iteration, that is, inverse iteration with guaranteed accuracy, is presented. A new implementation of the Cullum-Willoughby-Lanczos method, that is the Lanczos method, with guaranteed accuracy for computing the partial spectral decomposition of real symmetric matrices and the partial singular value decomposition of large sparse nonsymmetric matrices, is also presented. An inverse iteration with guaranteed accuracy is used for estimating the accuracy and, if necessary, for computing eigenvectors and singular vectors.     

用于防抱制动系统的路面不平特征识别算法

为提高防抱制动系统(ABS)在不平路面上的控制效果,研究ABS在不平路面上的信号特征和路面不平度识别方法。建模仿真可证明从轮加速度信号中识别路面不平度的可行性;对加速度信号的时域频域分析,提出识别路面不平度的“能量比重法”和 “穿越计次法”;提出基于多级穿越门限、多级不平累加值及自减参数的ABS路面不平度实时识别算法;对基于路面不平度识别的ABS不平路面补偿算法进行初步研究。结果表明,该算法实时性好,能准确识别路面不平度,计算量小,能满足ABS实时控制需要。     

利用脉冲耦合神经网络的图像融合

为了获得对同一场景更为准确、全面和可靠的图像描述,提出了一种基于脉冲耦合神经网络(PCNN)的图像融合方法。将多源传感器图像配准后的各个源图像用9/7小波变换的提升算法进行分解,从而得到各个源图像的低频分量和高频分量。对于低频分量,采用像素绝对值选大法进行融合;而高频分量则作为PCNN的输入,在迭代结束后,通过比较PCNN点火次数得到一系列融合子图像;然后,用9/7小波的提升算法将获取的一系列多尺度融合子图像进行反变换得到最终的融合图像。设计了可见光图像与红外图像的融合实验,对融合图像的熵、平均梯度、标准差、空间频率进行了定量比较。当使用标准源图像进行融合时,各值比使用传统小波变换与PCNN相结合的图像融合方法分别高0.0104,0.2459,0.1131和0.2846。     

基于改进遗传算法的模糊张力控制

针对张力系统实时性的特点,提出了基于改进遗传算法的模糊控制器。该文对遗传优化的模糊控制器进行了改进：1）采用多调整因子的模糊控制器;2）引入超代遗传（HGGA）方法;3）对染色体个体编索引号,尽量避免其近亲繁殖。最后在张力平台上验证了上述算法,结果表明,上述控制方法有效地实现了张力的实时控制。     

基于Steffensen迭代法的NURBS曲线插补算法

为了解决NURBS曲线参数插补及其实时性的问题,提出一种新的基于Steffensen迭代法的NURBS曲线参数快速求解方法。算法首先采用线性多步法进行精确的参数值预估,然后结合弓高误差、进给速度等加工条件进行自适应速度规划,再根据规划步长进行参数值迭代校正。算法不需求导,计算快速精确,满足加工精度和数控系统实时性要求。     

基于ARM7的二代身份证信息采集系统

为了满足对第二代身份证信息采集的需要,以ARM7为微处理器设计了一款嵌入式信息采集系统。在这一系统的设计中,运用了液晶图形化显示技术。测量和控制数据处理技术。信息存储和管理技术,ARM与GSM模块的通信技术等。较好地满足了采集要求。同时结合实际需要。移植了UC／OS-Ⅱ实时操作系统,从而实现了系统的智能化、信息化及网络化。     

Control of a dual stage magnetostrictive actuator and linear motor feed drive system

A dual stage feed drive system is well suited to satisfying current demands of high performance machining with tight position control under high feed rates in the presence of disturbances. It does this by integrating an actuator with high position resolution and fast response together with a conventional linear drive. A magnetostrictive actuator (MA) with a bandwidth in the kHz range capable of several kN of force output is an ideal candidate for use as the fine positioning element in such a dual stage system. However, MAs display significant hysteresis in their performance. This makes the effective implementation of real-time fast servo control challenging. In this paper, a dynamic Preisach model is utilized to reduce the undesired nonlinearity. A sliding mode controller (SMC) is designed to deal with uncertainties such as the Preisach modeling error as well as external disturbances so as to ensure a robust stable system. Experimental results show the servo performance improvement during a feed step test for single axis control and a single axis component of a sharp path interpolation test.     

基于FPGA的9/7小波变换算法实现

提出了一种基于现场可编程门阵列(FPGA)的高速9/7二维离散小波变换(2-D DWT)设计。在实现一维离散小波变换(1-D DWT)时采用多级流水线技术,并使用了改进的提升算法。同时,使用正则符号编码(CSD编码)和优化的移位加法操作实现乘法器,使其便于通过硬件实现,且加快了处理速度。在进行二维离散小波变换时采用改进的基于行的结构,只需完成3行行变换即可开始列变换,减少了系统资源的占用。设计通过MATLAB与ModelSim联合仿真,可以稳定运行在60MHz时钟频率下,完全能够满足高速图像实时处理的要求。