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91.
Feng Tyan 《Asian journal of control》2016,18(3):899-919
In this work, the capture region of the general ideal proportional navigation guidance law is analyzed with the following constraints: (i) the target's input acceleration is subject to independent or magnitude saturation, and (ii) the missile's input acceleration is subject to magnitude saturation. In addition to the case of unbounded maneuverability of missile with or without knowing the target acceleration, the necessary and sufficient condition for a bounded maneuvering missile that captures a nonmaneuvering target is also derived. Furthermore, the conditions that result in zero impact velocity are discovered and discussed in some of the cases. The capture regions that cannot be obtained analytically are determined numerically by a powerful classifier, the least square support vector machines. To have the capture region ready for least square support vector machines, all the state variables are transformed into modified polar variables and non‐dimensionalized to reduce the number of independent variables. In order to make the implementation possible in real time, an approximation of the Gaussian radial basis function is adopted to obtain the corresponding nonlinear feature mapping function. Through numerous numerical experiments, the proposed technique is found to be adequate for storing the capture region in an onboard fire control computer. 相似文献
92.
The main aim of this paper is to investigate the group decision making on incomplete multiplicative and fuzzy preference relations without the requirement of satisfying reciprocity property. This paper introduces a new characterization of the multiplicative consistency condition, based on which a method to estimate unknown preference values in an incomplete multiplicative preference relation is proposed. Apart from the multiplicative consistency property among three known preference values, the method proposed also takes the multiplicative consistency property among more than three values into account. In addition, two models for group decision making with incomplete multiplicative preference relations and incomplete fuzzy preference relations are presented, respectively. Some properties of the collective preference relation are further discussed. Numerical examples are provided to make a discussion and comparison with other similar methods. 相似文献
93.
In this paper, we first introduce the generalized alternated system. The definition of the Julia set in the generalized alternated system is given, which is called a generalized alternated Julia set. Then, we achieve the control of generalized alternated Julia sets by applying the classic control methods, which are gradient control and optimal control. In addition, the synchronization between two different generalized alternated Julia sets is implemented using gradient control and optimal control. The simulations illustrate the effectiveness and correctness of these two control methods, and the results are displayed in 2D computer graphics. 相似文献
94.
建立二阶自治广义Birkhoff系统的微分方程.给出该系统的线性化方程,得到该线性方程转化为梯度系统的条件,利用梯度系统的性质对线性系统的奇点进行了分析,然后再利用Perron定理探讨了相应的非线性系统的奇点类型.结果表明,如果线性系统能成为梯度系统,那么相应的非线性系统的奇点可能是结点或者鞍点. 相似文献
95.
Stephen Abell Nhan Do 《International Journal of Parallel, Emergent and Distributed Systems》2016,31(5):450-468
This article presents a GPU-based single-unit deadlock detection methodology and its algorithm, GPU-OSDDA. Our GPU-based design utilizes parallel hardware of GPU to perform computations and thus is able to overcome the major limitation of prior hardware-based approaches by having the capability of handling thousands of processes and resources, whilst achieving real-world run-times. By utilizing a bit-vector technique for storing algorithm matrices and designing novel, efficient algorithmic methods, we not only reduce memory usage dramatically but also achieve two orders of magnitude speedup over CPU equivalents. Additionally, GPU-OSDDA acts as an interactive service to the CPU, because all of the aforementioned computations and matrix management techniques take place on the GPU, requiring minimal interaction with the CPU. GPU-OSDDA is implemented on three GPU cards: Tesla C2050, Tesla K20c, and Titan X. Our design shows overall speedups of 6-595X over CPU equivalents. 相似文献
96.
97.
针对轴承振动信号中的故障信息往往很微弱,同时振动样本数据分布不平衡即故障样本占总样本数的比例低,从而导致故障诊断模型训练不精确而影响诊断精度的问题,提出了一种基于拉普拉斯分值和超球大间隔支持向量机的故障诊断方法;首先,采用有标签的训练样本数据和拉普拉斯分值法提取原始振动信号中的微弱故障信息,并降低其数据维数,从而得到用于故障诊断的特征向量,然后设计了一种改进的超球大间隔支持向量机的故障诊断模型,通过最小化超球体积和最大化超球边界和故障样本之间的间隔来实现故障诊断,以解决样本的不均衡问题,最终通过将测试样本数据代入决策方程并通过投票机制确定其故障类别;在Matlab环境下对轴承故障诊断进行实验,实验结果证明了文中方法能有效解决样本的不均衡情况下的故障诊断,且相对其它方法,具有诊断精度高和收敛速度快的优点. 相似文献
98.
李晨 《计算机与数字工程》2015,(2):316-319
构造分类器是图像分割中重要的处理环节,论文将先验知识引入支持向量机,对支持向量机做了改善,在改善的支持向量机基础上构造实现了一个分类器,重点是将为了检验分类器的有效性,通过对UCI机器学习数据库的数据进行的实验,实验结果表明改善的支持向量机分类准确率比支传统持向量机的准确率高。 相似文献
99.
在线编程技术是单片机应用系统的常用技术,其广泛应用为产品的设计、调试、生产、升级带来了极大的便利。本文通过"搬迁中断向量表"的方法为市面上众多支持IAP功能的单片机提供一种实现ISP功能的完美解决方案,在仅支持IAP功能的CPU上实现了ISP。 相似文献
100.
Despite the fact that progress in face recognition algorithms over the last decades has been made, changing lighting conditions and different face orientation still remain as a challenging problem. A standard face recognition system identifies the person by comparing the input picture against pictures of all faces in a database and finding the best match. Usually face matching is carried out in two steps: during the first step detection of a face is done by finding exact position of it in a complex background (various lightning condition), and in the second step face identification is performed using gathered databases. In reality detected faces can appear in different position and they can be rotated, so these disturbances reduce quality of the recognition algorithms dramatically. In this paper to increase the identification accuracy we propose original geometric normalization of the face, based on extracted facial feature position such as eyes. For the eyes localization lbllowing methods has been used: color based method, mean eye template and SVM (Support Vector Machine) technique. Experimental investigation has shown that the best results for eye center detection can be achieved using SVM technique. The recognition rate increases statistically by 28% using face orientation normalization based on the eyes position. 相似文献