超临界机翼静气动弹性特性研究

采用三维Euler方程为控制方程，计算机翼所受的气动力与静气动弹性平衡方程耦合求解，研究超临界机翼的静气动弹性规律，并以超临界弹性机翼和普通弹性机翼为算例，计算弹性飞机飞行中的真实载荷和扭转变形，并在已知弹性机翼飞行时总载荷保持不变的情况下，确定超临界机翼结构弹性在飞行中对载荷的影响。     

基于多维约束空间的自动制图综合质量评估模型

为解决现阶段自动制图综合结果难以量化和比较的问题，提出一种基于多维约束空间的制图综合质量评估模型．首先对综合结果所得的各约束值进行归一化和无量纲处理，然后在单个一维约束坐标轴的基础上建立虚拟的多维约束空间，使综合结果在同一尺度范围内进行讨论，最后把欧氏距离扩展到多维约束空间用来度量制图综合质量以进行质量优劣的比较．使用该方法对普通建筑物的不同综合结果进行了评估，计算了面积、相邻点之间距离等5个建筑物约束条件所得制图综合结果的综合评价值，按照该综合评价值的排序获取的质量评估结果与实际情况完全符合．结果证明，该方法原理正确，计算简单，是评价和比较多个制图综合结果的有效方法．     

A relation between edit distance for ordered trees and edit distance for Euler strings

We consider a relationship between the unit cost edit distance for two rooted ordered trees and the unit cost edit distance for the corresponding Euler strings. We show that the edit distance between trees is at least half of the edit distance between the Euler strings and is at most 2h+1 times the edit distance between the Euler strings, where h is the minimum height of two trees. The result can be extended for more general cost functions.     

子样广义方差的分布函数及其计算

本文以傅氏级数为基础，巧妙地利用了契贝谢夫多项式，成功地给出了子样广义方差的分布函数及其计算过程。     

A Distributed Ant Algorithm for\protect Efficiently Patrolling a Network

We consider the problem of patrolling—i.e. ongoing exploration of a network by a decentralized group of simple memoryless robotic agents. The model for the network is an undirected graph, and our goal, beyond complete exploration, is to achieve close to uniform frequency of traversal of the graphs edges. A simple multi-agent exploration algorithm is presented and analyzed. It is shown that a single agent following this procedure enters, after a transient period, a periodic motion which is an extended Eulerian cycle, during which all edges are traversed an identical number of times. We further prove that if the network is Eulerian, a single agent goes into an Eulerian cycle within 2|E|D steps, |E| being the number of edges in the graph and D being its diameter. For a team of k agents, we show that after at most 2( 1 + 1/k) |E|D steps the numbers of edge visits in the network are balanced up to a factor of two. In addition, various aspects of the algorithm are demonstrated by simulations.     

关于V带传动当量摩擦系数计算公式的修正

对现行机械设计中关于V带传动当量摩擦系数的2种计算公式进行分析.认为其中一种公式是合理的,但存在一定的误差;而另一种公式却是错误的.通过推导V带欧拉公式,给出了计算V带传动当量摩擦系数的准确公式,并在公式中引入了一个新的参数——摩擦力方向角.在考虑皮带拉力变化既有径向滑动又有周向滑动的前提下,改进后的计算公式比现有公式更加完善.     

V带传动中轴向压力的研究

介绍了摩托车上常用的V型皮带式无级变速器的工作原理.通过对V型皮带式无级变速器主动轮和从动轮的力学分析,建立了皮带传动的力学关系,推导了这种传动的设计公式,并指出了现有公式的不足,在公式中引入了一个新的参数———摩擦力方向角,给出了计算V带传动当量摩擦系数的准确公式.     

Distributed leaderless consensus algorithms for networked Euler–Lagrange systems

This article proposes and analyses distributed, leaderless, model-independent consensus algorithms for networked Euler–Lagrange systems. We propose a fundamental consensus algorithm, a consensus algorithm accounting for actuator saturation, and a consensus algorithm accounting for unavailability of measurements of generalised coordinate derivatives, for systems modelled by Euler–Lagrange equations. Due to the fact that the closed-loop interconnected Euler–Lagrange equations using these algorithms are non-autonomous, Matrosov's theorem is used for convergence analysis. It is shown that consensus is reached on the generalised coordinates and their derivatives of the networked Euler–Lagrange systems as long as the undirected communication topology is connected. Simulation results show the effectiveness of the proposed algorithms.     

Distributed adaptive containment control for networked uncertain Euler–Lagrange systems

The paper is concerned with the containment problem of a multi-agent system with each agent being described by an Euler–Lagrange (EL) equation with uncertain parameters. Distributed adaptive control laws are proposed such that the generalised positions of the EL systems converge to the target convex set without measuring or observing neighbours' velocities. Moreover, exponential rate convergence is obtained when the regressor matrix of each EL system is of full column rank. As a byproduct, some of the uncertain parameters existing in the EL systems can be identified under the full column rank condition. Finally, the effectiveness of the proposed method is validated through the simulations on a group of networked uncertain robots.     

Sufficient LMI stability conditions for Lur’e type systems governed by a control law designed on their Euler approximate model

In this paper, the stability issue of Lur’e systems governed by a control law stabilising their forward Euler approximate model is investigated. More specifically, the considered control law is obtained by exploiting the advantages of a new Lur’e type Lyapunov function with disconnected level sets. This Lyapunov function is adapted to discrete-time Lur’e systems and to the structure of the forward Euler approximate model. The main result consists of linear matrix inequality conditions allowing to guarantee that the continuous-time Lur’e system associated with the proposed digital control law is globally asymptotically stable. The relevance of this approach is illustrated using a numerical example.