基于固定增量单样本感知器的AdaBoost算法

针对传统AdaBoost算法在分类过程中时间复杂度和算法学习复杂度较高的问题,提出一种改进的算法AdaBoostFISP。以固定增量单样本感知器为弱分类器,在感知器的权值更新上采用固定增量代替变量增量,从而减少运算时间、降低学习复杂度。实验结果证明了该算法在预测准确性、学习复杂度和时间复杂度等方面的优势。     

基于定长时隙的多跳Ad Hoc网络DCF协议马尔可夫链模型

指出了现有的基于不定长时隙的DCF协议马尔可夫链模型的局限性,并在详细分析多跳ad hoc 网络环境中DCF 协议建模的难点问题基础上,提出了一种基于定长时隙的多跳ad hoc 网络DCF 协议马尔可夫链模型.通过模型的求解,得到了反映多跳ad hoc 网络饱和吞吐量性能的相关性能指标的理论值,并结合GloMoSim 网络仿真环境中的仿真实验,证明了模型的有效性.     

团分划问题的固定参数算法研究

图论中的团分划问题属于NP-完全问题,难以在多项式时间内解决。为此,对团分划问题的固定参数算法进行研究,提出一个针对K4-free图的新归约法则,结合深度限制搜索树技术对K4-free图中的团分划固定参数可解类算法做出改进。实验结果表明,与原算法相比,在稀疏图的情况下改进算法效率提高了30%。     

Coupled common fixed point theorems for a pair of commuting mappings in partially ordered complete metric spaces

The purpose of this paper is to establish a coupled coincidence point for a pair of commuting mappings in partially ordered complete metric spaces. We also present a result on the existence and uniqueness of coupled common fixed points. An example is given to support the usability of our results.     

微球探针制备工艺的优化

为了解决现有激光微球探针加工技术中存在的探针尖端微球球心偏离针杆中轴线的问题,提出了一个两步法加工策略.以CO2激光光束为热源,对探针针杆尖端进行加热,使针杆尖端受热融化产生微球.然后将带有微球的探针针杆绕其中轴线旋转180°,再使用CO2激光光束辐照带有微球的探针尖端,对尖端微球偏移量进行补偿.实验结果表明:采用“熔球-旋转再熔球”的两步法加工策略,能明显降低探针尖端微球相对于针杆的弯曲程度,缩小探针尖端球形球心和针杆中心线的偏移距离.     

Some fixed point theorems in 1-M-complete fuzzy metric-like spaces

Very recently, in order to unify the notions of fuzzy metric space and metric-like space, Shukla and Abbas introduced the concept of fuzzy metric-like space and proved some fixed-point results in this setting. In this article, we modify the notion of Cauchy sequence and completeness to generalize their results. Thus, we extend their theorems to a more general framework, which is also appropriate to generalize some recent, well-known results in this line of research. Furthermore, several examples are presented to illustrate the significance of our results.     

一种新的双足机器人模型设计与相关研究

针对双足机器人最简模型在行走过程中出现摆动腿足部擦地的问题,提出了一种通过摆动腿膝关节弯曲达到摆动腿缩短的新模型。当摆动腿开始摆动时,摆动腿膝关节弯曲锁定,摆动腿缩短;当摆动腿摆动到最大位置时,膝关节解锁,摆动腿伸直再锁定,此后摆动腿回摆,系统变为直腿模型。采用脚后跟冲击控制,在摆动腿落地前,拖后的支撑腿与地面接触处施加一指向髋关节的瞬时冲击力,冲击力可以减小摆动腿着地时能量的损耗,同时驱动被动机器人向前行走。设计了迭代学习控制算法,找到极限环与不动点,实现不同给定期望步长跟踪的冲击力的计算。仿真结果表明,迭代学习控制可以有效的实现不同期望步长的跟踪,可以很快的找到机器人系统的不动点,通过收敛的相平面,得到稳定的极限环,保证了机器人行走过程稳定。     

A training-free nose tip detection method from face range images

Nose tip detection in range images is a specific facial feature detection problem that is highly important for 3D face recognition. In this paper, we propose a nose tip detection method that has the following three characteristics. First, it does not require training and does not rely on any particular model. Second, it can deal with both frontal and non-frontal poses. Finally, it is quite fast, requiring only seconds to process an image of 100-200 pixels (in both x and y dimensions) with a MATLAB implementation. A complexity analysis shows that most of the computations involved in the proposed algorithm are simple. Thus, if implemented in hardware (such as a GPU implementation), the proposed method should be able to work in real time. We tested the proposed method extensively on synthetic image data rendered by a 3D head model and real data using FRGC v2.0 data set. Experimental results show that the proposed method is robust to many scenarios that are encountered in common face recognition applications (e.g., surveillance). A high detection rate of 99.43% was obtained on FRGC v2.0 data set. Furthermore, the proposed method can be used to coarsely estimate the roll, yaw, and pitch angles of the face pose.     

Analyzing the structure of a class of linear automata over a ring $$ Z_{p^k } $$

Basic finite-automaton characteristics are established for the class of all linear automata and information-lossless automata over a ring. The complexities of solving problems of parametric identification and initial-state identification are analyzed. The sets of fixed points for mappings realized by initial automata are characterized. Canonical forms are proposed for linear automata over the ring. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 60–74, May–June 2008.     

Approximate fixed point sequence for a finite family of asymptotically pseudocontractive mappings

Let E be a real Banach space and K be a nonempty, closed, convex, and bounded subset of E. Let T_i:K→K, i=1,2,…,N, be N uniformly L-Lipschitzian, uniformly asymptotically regular with sequences {ε_n}, and asymptotically pseudocontractive mappings with sequences , where {ε_n} and , i=1,2,…,N, satisfy certain mild conditions. Let a sequence {x_n} be generated from x₁K by

for all integers n1, where T_n=T_n(modN), {u_n} be a sequence in K, and {λ_n}, {θ_n} and {μ_n} are three real sequences in [0,1] satisfying appropriate conditions; then x_n−T_lx_n→0 as n→∞ for each l{1,2,…,N}.