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1.
DSP和MAX125/126在电力参数测量中的应用   总被引:2,自引:0,他引:2  
介绍利用TMS320X240的CAP捕捉单元和T3定时器实现定时捕捉功能。通过同步采样工频信号实现电参数测量。同时介绍了高速位带多路开关及采样保持器ADC(MAX125/126)的使用方法。  相似文献   

2.
介绍一种基于FPGA的随机脉冲信号快速捕捉系统的系统结构、工作原理和实现方法;该系统完全摆脱了传统数据采集系统在采集深度和采样效率方面的制约因素,能够在整个时域范围内对外部信号进行连续的高速采样;系统工作过程中不需要外部控制器的干涉,完全由FPGA内部的硬件逻辑电路实现对随机脉冲信号的快速、精确捕捉,可靠性高;抗干扰能力强,同时具有很高的采样效率.  相似文献   

3.
本文研究利用数字信息处理器(DSP)TMS320X240的CAP捕捉单元和T3定时器实现精确定时捕捉功能。通过同步采样工频信号,保证实现电力参数高精度测量。同时阐述了用高速14位带多路开关及采样保持器数模转换芯片MAX125实现三相多参数信号采样,构成了电力参数监测系统。  相似文献   

4.
针对传统NSCT(非下采样轮廓波变换)算法中NSP(多尺度分解方法)对细节信息捕捉能力较差及利用其进行图像融合得到的融合图像出现细节丢失问题,提出改进的NSCT算法。不同于传统NSCT算法,该算法首先采用细节捕捉能力较强的非下采样形态学小波分解替代NSP分解,实现对源图像的多尺度分解,将源图像分解成水平高频、垂直高频、对角高频和低频4部分;然后利用NDFB(非下采样的方向性滤波器)对高频部分进行多方向分解得到一系列高频信息,实现改进型NSCT分解。实验结果表明,该算法的细节捕捉能力较传统算法好,在相同融合规则下其图像融合效果更好,各项融合指标值均有所提高,其中平均梯度提高了10%,且易于实现,可广泛用于多分辨率图像融合,是一种有效的融合图像算法。  相似文献   

5.
运动捕捉及其在动画制作中的应用   总被引:5,自引:0,他引:5  
黄波士  陈福民 《计算机工程》2005,31(13):168-170
提出了基于运动捕捉技术的动画制作,介绍了运动捕捉技术的过程及其3个关键技术的实现。给出了运动捕捉系统的模型和具体的实现方法。对于图像捕捉的同步问题进行了分析和解决。论述了基于运动捕捉技术的动画制作过程中的动画合成和消除滑步等技术。  相似文献   

6.
《软件》2018,(2):75-80
本文针对卷积神经网络中最大池化会丢失对图像分类"有用"信息的问题,提出全采样方法和基于L1范数的降采样方法。全采样方法利用所有输入,基于L1范数的降采样方法把输入划分为不重叠的2×2的部分,从每个2×2的部分中选择L1范数最大的k(k=1,2,3)个1×1的部分实现降采样。为验证所提方法有效性,在CIFAR-10数据集和MNIST数据集上进行实验,结果表明,相比最大池化,所提方法可以在参数量不增加的基础上提高图像分类准确率。  相似文献   

7.
基于USB2.0的高速同步数据采集系统设计   总被引:14,自引:0,他引:14  
介绍基于USB2.0协议、最多可四路同步采样的高速同步数据采集系统。其单通道采样速度620ksps,四通道同时采样速度可达180ksps。USB接口控制及通信芯片采用Cypress公司FX2系列中的CY7C68013,通过对其可编程接口控制逻辑的合理设计和芯片内部FIFO的有效运用,实现了数据的高速连续采样。  相似文献   

8.
交流采样的设计与实现   总被引:6,自引:6,他引:0  
本文介绍了以单片机为基础的交流电压、电流直接采样的设计与实现并用锁相环CD4046来实现相位角的采样。  相似文献   

9.
卫星定位接收机高精度伪码跟踪的设计与实现   总被引:1,自引:0,他引:1  
在卫星定位接收机中,伪码跟踪的精度直接影响定位精度。介绍了延迟锁相环及其数学模型。在对比分析等量采样和非等量采样条件下延迟锁相环跟踪精度的基础上,提出了采用非等量采样延迟锁相环的伪码跟踪数字实现方案。该方案复杂度低,易于实现。实验结果表明该方案对码速率为10.23 MHz的伪码跟踪精度可达1 ns,实现了伪码的精确同步。该设计已应用于卫星定位接收机的研制开发中。  相似文献   

10.
本文采用美国国家半导体公司的高速双通道模数转换器(ADC08D1000),以及Altera公司CycloneII系列的FPGA(EP2C70F896C8)实现对双路信号的高速采样,每片ADC通过交叉采样对每路信号的采样率达到2GSPS。本文着重介绍电路的设计,以及PCB制版过程当中的技巧问题。  相似文献   

11.
In this paper, a distributed selectsort algorithm and a parameterized selectsort algorithm are presented to be applied on distributed systems for cases when N P where N is the number of elements to be sorted and P is the number of processors in the system. The distributed system considered in this paper uses a broadcasting channel for communication between processors. We show that the number of messages required for the parameterized selectsort algorithm is independent of N and is of complexity O(P), which is optimal in a distributed system with P processors. Furthermore, the amount of communication required in terms of elements is N + O(P3) and the computation time complexity is O((N/P)lgN + P2lg(N/P)). Hence, when N P3, the computation time complexity is O((N/P)lgN), which is optimal using P processors. In addition, this parameterized algorithm provides us with a parameter K such that by choosing the value of K allows us to trade among processing requirement, memory requirement, and communication requirement. It is shown that this parameterized algorithm can reduce the communication requirements significantly while only slightly increasing the computation requirements.  相似文献   

12.
For an ordered set W = {w1, w2,…, wk} of vertices and a vertex v in a connected graph G, the (metric) representation of v with respect to W is the k-vector r(v | W) = (d(v, w1), d(v, w2),…, d(v, wk)), where d(x, y) represents the distance between the vertices x and y. The set W is a resolving set for G if distinct vertices of G have distinct representations. A new sharp lower bound for the dimension of a graph G in terms of its maximum degree is presented.

A resolving set of minimum cardinality is a basis for G and the number of vertices in a basis is its (metric) dimension dim(G). A resolving set S of G is a minimal resolving set if no proper subset of S is a resolving set. The maximum cardinality of a minimal resolving set is the upper dimension dim+(G). The resolving number res(G) of a connected graph G is the minimum k such that every k-set W of vertices of G is also a resolving set of G. Then 1 ≤ dim(G) ≤ dim+(G) ≤ res(G) ≤ n − 1 for every nontrivial connected graph G of order n. It is shown that dim+(G) = res(G) = n − 1 if and only if G = Kn, while dim+(G) = res(G) = 2 if and only if G is a path of order at least 4 or an odd cycle.

The resolving numbers and upper dimensions of some well-known graphs are determined. It is shown that for every pair a, b of integers with 2 ≤ ab, there exists a connected graph G with dim(G) = dim+(G) = a and res(G) = b. Also, for every positive integer N, there exists a connected graph G with res(G) − dim+(G) ≥ N and dim+(G) − dim(G) ≥ N.  相似文献   


13.
A subdivision scheme for constructing smooth surfaces interpolating scattered data in R3 is proposed. It is also possible to impose derivative constraints in these points. In the case of functional data, i.e., data are given in a properly triangulated set of points {(xi, yi)}i=1N from which none of the pairs (xi,yi) and (xj,yj) with ij coincide, it is proved that the resulting surface (function) is C1. The method is based on the construction of a sequence of continuous splines of degree 3. Another subdivision method, based on constructing a sequence of splines of degree 5 which are once differentiable, yields a function which is C2 if the data are not ‘too irregular’. Finally the approximation properties of the methods are investigated.  相似文献   

14.
A heap structure designed for secondary storage is suggested that tries to make the best use of the available buffer space in primary memory. The heap is a complete multi-way tree, with multi-page blocks of records as nodes, satisfying a generalized heap property. A special feature of the tree is that the nodes may be partially filled, as in B-trees. The structure is complemented with priority-queue operations insert and delete-max. When handling a sequence of S operations, the number of page transfers performed is shown to be O(∑i = 1S(1/P) log(M/P)(Ni/P)), where P denotes the number of records fitting into a page, M the capacity of the buffer space in records, and Ni, the number of records in the heap prior to the ith operation (assuming P 1 and S> M c · P, where c is a small positive constant). The number of comparisons required when handling the sequence is O(∑i = 1S log2 Ni). Using the suggested data structure we obtain an optimal external heapsort that performs O((N/P) log(M/P)(N/P)) page transfers and O(N log2 N) comparisons in the worst case when sorting N records.  相似文献   

15.
A new family of network topologies containing multiple loops is discussed in this paper. In the proposed structure, N processors are interconnected to form a graph G(m, N), m 3, where m is a parameter of the graph such that N is an even multiple of m and (m − 1) × 2[(m− l)/2]+ < N m × 2[m/2]+1. The graph G(m, N) is hamiltonian with an average node degree (3 + l/m), when m is even and exactly 3 when m is odd. Whereas, the maximum node degree is 4. The diameter of G(m, N) is upper bounded by [11m/8]+ 1. A point to point routing algorithm has been presented. Implementation of ASCEND/DESCEND algorithms in O(m) time has been discussed. It has been shown that in case of a single node failure, the diameter increases by at most 6.  相似文献   

16.
李岳炀  钟麦英 《自动化学报》2015,41(9):1638-1648
研究存在多数据包丢失现象的线性离散时变系统有限时间域内故障检测滤波器(Fault detection filter, FDF)设计问题. 在数据包具有时间戳标记的条件下, 设计基于观测器的FDF作为残差产生器, 构造两类FDF. 其一为H-/H∞-FDF或H∞/H∞-FDF. 定义故障到残差和未知输入到残差的广义传递函数算子, 将此类FDF设计问题转换为随机意义下H-/H∞ 或H∞/H∞性能指标优化问题. 其二为H∞-FDF, 将此类FDF设计问题转化为随机意义下的H∞滤波问题. 采用基于伴随算子的H∞优化方法, 通过求解递推Riccati方程, 得到上述两类FDF设计问题的解析解. 通过算例验证所提方法的有效性.  相似文献   

17.
For each nonempty binary word w=c1c2cq, where ci{0,1}, the nonnegative integer ∑i=1q (q+1−i)ci is called the moment of w and is denoted by M(w). Let [w] denote the conjugacy class of w. Define M([w])={M(u): u[w]}, N(w)={M(u)−M(w): u[w]} and δ(w)=max{M(u)−M(v): u,v[w]}. Using these objects, we obtain equivalent conditions for a binary word to be an -word (respectively, a power of an -word). For instance, we prove that the following statements are equivalent for any binary word w with |w|2: (a) w is an -word, (b) δ(w)=|w|−1, (c) w is a cyclic balanced primitive word, (d) M([w]) is a set of |w| consecutive positive integers, (e) N(w) is a set of |w| consecutive integers and 0N(w), (f) w is primitive and [w]St.  相似文献   

18.
A method of obtaining reduced order models for multivariable systems is described. It is shown that the method has several advantages, e.g. the reduced order models retain the steady-state value and stability of the original system. Irrespective of whether the original multivariable system is described in state space form or in the transfer matrix form, the proposed method yields the reduced order models in state space form. In this method the Routh approximation is used to formulate the common denominator polynomial of a reduced order model. This is used to describe the structure of Ar matrix. The matrices Br and Cr are chosen appropriately and some of the elements of Br/Cr matrices are specified in such a way that after matching time moments/Markov parameters, the resulting equations are linear in the unknown elements of Br and Cr matrices. The procedure is illustrated via a numerical example.  相似文献   

19.
Simulating a network by a smaller one with the same interconnection structure is also called emulation. In this paper, an efficient emulation for simulating an X-tree by another X;lree of smaller size is proposed. The proposed emulation is load-balanced and of 1-dilation. And, the congestion is The proposed emulation is optimal with respect to load and dilation. Besides, our emulation has the following advantages. First, it is simple and thus easy to compute. While using our emulation to simulate an X-tree C by a smaller X-tree H, we can easily determine the node that is responsible for simulating a given node of G in O(1) time. And, we can determine the nodes that are simulated by a given node of H in O(|G|/|H|)time. Second, our emulation can be directly applied to emulate a tree by another tree of smaller size without losing any efficiency. Finally, our emulation has the property that a root node is simulated by a root node and a leaf node is simulated by a leaf node. This property makes our emulation suitable for X-trees in which root nodes and leaf nodes should perform some special operations that cannot be performed by other internal nodes. For example, most algorithms designed on X-trees assume that only the root and leaf nodes can perform I/O operations.

The m-ary tree is a generalization of the binary tree, where m ? 2 and is an integer. In this paper, we also propose an efficient emulation for n;-ary trees. The proposed emulation for m-ary trees is load-balanced and of I-dilation. And, the congestion is   相似文献   

20.
This paper is concerned with the separated control problems for optimal stochastic controls under partial observations. The ‘pathwise’ method of nonlinear filtering is extended to the case when a function h(XtYt, of state Xt, and observation Yt 3plus additive white noise is observed. Markov and continuity properties of the unnormalized conditional distribution measure are obtained and the Nisio nonlinear semigroup is found.  相似文献   

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