支持QoS的覆盖组播分布式动态路由研究

研究了带度和延时约束的覆盖组播动态路由问题,提出了动态适应性覆盖组播路由协议OMP,给出了一个基于分布式触发重组的组播路由算法——动态覆盖组播路由算法(DDCOMR),最后对该算法的复杂度进行了推证,对协议和算法的有效性进行了网络模拟。     

Observability theorems for some linear hyperbolic systems

In this paper the observability of systems of first-order hyperbolic partial differential equations is investigated. Both systems with boundary measurements and systems with distributed measurements are considered. In the case of boundary measurements a sufficient condition is found for observability. This condition is shown also to be necessary for systems defined on a one-dimensional space domain, as well as in other special cases. In the case of linear distributed measurements, a necessary and sufficient condition for observability is derived. The theorems are applicable for example to linearized hydrodynamical flow equations and to industrial flow system equations.     

CC$:一种面向分布式众核平台的并行编程语言

CC$是一种并行编程语言,目的是解决分布式众核并行计算机的编程困难。CC$的编程模型以Multi BSP 模型为基础,将分布式众核并行计算机的硬件架构抽象为3层。数据按照存储的层次和共享范围分为5类,以便在不 同层次上提供共享。LL$还提出一类虚拟指令来解决不同层次之间的数据交换,实现数据访问的逻辑化描述。并行 程序按照3层Multi BSP超步嵌套执行。CC$具有统一的编程风格、内建的多层会共地址空间、数据访问请求的表达 式描述和数据传输编译优化4大特点。测试表明,CC$程序的运行效率高,易学易用,大幅地缩短了开发周期。     

Hybrid optimization implemented for distributed generation parameters in a power system network

This paper presents a novel hybrid optimization algorithm for optimizing the Distributed Generation (DG) parameters in deregulated power system which improves the stability, reduces the losses and also increases the cost of generation. This Hybrid algorithm which includes Fuzzy-Genetic Algorithm (FGA) is used to optimize the various DG parameters simultaneously. The various parameters taken into consideration are their type, location and size of the DG devices. The simulation was performed on a distribution system and modeled for steady state studies. The optimization results are compared to the solution given by another search method like Genetic Algorithm (GA) and Micro Genetic Algorithm (MGA). The results reveal the benefits of the proposed method, for solving simultaneous combinorial problems of DG devices in a power system network.     

基于Multi-agents系统的分布式数据挖掘

计算机网络的发展以及海量数据的分布式存储,滋生了分布式数据挖掘（DDM）这一新的数据挖掘方式。本文针对多agent系统下的分布式数据挖掘进行了初步的研究,对agent方法用于DDM的优势、基于agents的分布式数据挖掘的问题,以及典型的基于agent的分布式数据挖掘系统和该领域的进一步研究方向作了一个概要的综述。     

Stabilization of uncertain boundary control systems

We consider a class of linear infinite-dimensional systems subject to boundary uncertainties, which are linear and time-invariant. Using a deterministic approach to the design of stabilizing feedback controls, uniform exponential stability of the zero state is achieved. Lyapunov techniques are combined with Datko or Ichikawa theory. Three illustrative examples are presented.     

An efficient camera calibration and optimisation method based on orthogonal vanishing points

A more efficient camera calibration and optimisation method based on orthogonal vanishing points is proposed. After extracting corner points on the calibration images by using the Harris algorithm, some parallel lines are fitted via the least square method. The Levenberg–Marquard (L–M) algorithm is used to find out the optimum vanishing points. The intrinsic parameters are solved on the basis of the orthogonal vanishing point characters. The enhanced Tsai’s method is designed to solve the extrinsic parameters. The minimum residue optimisation function is introduced to calculate the distortion coefficients and optimise all parameters globally. The feasibility and efficiency of the proposed method is illustrated by an experimental study. The method can be used to obtain high precision calibration parameters without the need of sophisticated mechanical devices. It has great potential to calibration cameras in the field of computer vision, 3D measurement, etc.     

求解多目标优化问题的自适应混沌混合蛙跳算法

针对多目标优化问题提出一种自适应混沌混合蛙跳算法MACSFLA(Adaptive chaos shuffled frog leaping algorithm for multiobjective optimization)。使用动态权重因子策略以提高混合蛙跳算法SFLA(Shuffled Frog Leaping Algorithm)收敛效率,引入基于Pareto支配能力的SFLA子族群划分策略,使得SFLA能够应用于多目标优化问题。在此基础上,MACSFLA首先利用SFLA快速寻优能力接近理论Pareto最优解,然后采用自适应网格密度机制动态维护外部存储器Pareto最优解规模,并使用自适应混沌优化技术改善Pareto最优解集样本多样性,最后利用Pareto最优解选择策略为青蛙种群选择最优更新粒子。多目标函数测试实验结果表明,与MOPSO和NSGA-Ⅱ相比,MACSFLA在Pareto最优解集均匀性和多样性上有明显优势。     

Distributed evolutionary multi-objective mesh-partitioning algorithm for parallel finite element computations

Majority of the mesh-partitioning algorithms attempt to optimise the interprocessor communications, while balancing the computational load among the processors. However, it is desirable to simultaneously optimise the submesh aspect ratios in order to significantly improve the convergence characteristics of the domain decomposition based Preconditioned-conjugate-gradient algorithms, being used extensively in the state-of-the-art parallel finite element codes. Keeping this in view, a new distributed multi-objective mesh-partitioning algorithm using evolutionary computing techniques is proposed in this paper. Effectiveness of the proposed distributed mesh-partitioning algorithm is demonstrated by solving several unstructured meshes of practical-engineering problems and also benchmark problems.     

Reliability of complex chemical engineering processes

This paper presents a stochastic performance modelling approach that can be used to optimise design and operational reliability of complex chemical engineering processes. The framework can be applied to processes comprising multiple units, including the cases where closed form process performance functions are unavailable or difficult to derive from first principles, which is often the case in practice. An interface that facilitates automated two-way communication between Matlab^® and process simulation environment is used to generate large process responses. The resulting constrained optimisation problem is solved using both Monte Carlo Simulation (MCS) and First Order Reliability Method (FORM); providing a wide range of stochastic process performance measures. Adding such capabilities to traditional deterministic process simulators provides a more informed basis for selecting optimum design factors; giving a simple way of enhancing overall process reliability and cost-efficiency. Two case study systems are considered to highlight the applicability and benefits of the approach.