Fraction Arithmetic Operations Performed by P Systems

Arithmetical operations are fundamental in computing models. But arithmetic operations in mem- brane computing are restricted in integer field. In this paper, we present fraction arithmetic P systems for per- forming addition, subtraction, multiplication＇s division on fractions through designing the rules with priority. Some examples are given to illustrate how to compute the arith- metical fractions in these systems and show that the de- signed rules can carry out correct arithmetic computations of fractions.     

Arithmetic Expression Evaluations with Membranes

Arithmetic operations and expression eval- uations are fundamental in computing models. This paper firstly designs arithmetic membranes without priority rules for basic arithmetic operations, and then proposes an algo- rithm to construct expression P systems based on several of such membranes after designing synchronous and asyn- chronous transmission strategies among the membranes. For any arithmetic expression, an expression P system can be built to evaluate it effectively. Finally, we discuss differ- ent parallelism strategies through which different expres- sion P systems can be built for an arithmetic expression.     

Automatic Design of P Systems for Five Basic Arithmetic Operations within One Framework

To solve the programmability of a mem- brane system, this paper presents an automatic design method of a cell-like P system framework for performing five basic arithmetic operations. This method proved that different P systems can be designed with same framework by programming. A technique is introduced to remove re- dundant rules in the process of the design of a P system. The effectiveness and feasibility of this method is verified by experimental results.     

Application of Adaptive Fuzzy Spiking Neural P Systems in Fault Diagnosis of Power Systems

Adaptive fuzzy spiking neural P systems （AFSN P systems） are a novel kind of computing mod- els with parallel computing and learning ability. Based on our existing works, AFSN P systems are applied to deal wlth the fault diagnosis problems of power systems and the uncertainty of action messages about protective relays and breakers, and a new fault diagnosis model of power systems is proposed with simple reasoning process and fast speed with parallel processing capabilities. The effectiveness of the fault diagnosis model is verified by some examples of fault diagnosis. Furthermore, the learning ability of AFSN P systems can be applied to adjust the weights in the fault diagnosis model automatically.     

Evaluating Logical Expressions by Membrane Systems

Boolean and relational operations, which are defined for solving mathematically logical problems, are always required in computing models. Membrane com- puting is a kind of distributed parallel computing model. In this paper, we design different membranes for imple- menting primary Boolean and relational operations respec- tively. And based on these membranes, a membrane sys- tem can be constructed by a present algorithm for eval- uating a logical expression. Some examples are given to illustrate how to perform the Boolean, relational opera- tions and evaluate the logical expression correctly in these membrane systems.     

解非线性方程组的神经网络方法

本文提出了一种求解非线性方程组的神经网络方法,该方法对非线性方程组的任意给定的初始点,都能稳定地收敛到它的一个实根.文中首先严格地证明了该方法的稳定性、收敛性及可行性,然后给出了一个模拟算法及其应用.最后的数值试验结果表明该方法是有效的.     

求解非线性系统传递函数的递推组合法

本文给出了求解一类非线性系统传递函数的递推组合法,即根据系统Volterra响应的递推关系和组合系统传递函数的公式求解非线性系统传递函数的方法。     

云计算环境下支持多属性查找的混合对等网络

针对云计算环境下,云资源的多属性查找问题,设计了一种混合结构的对等网络。该网络采用多星形拓扑结构,将云资源以统一的编码方式规范化之后部署到该网络上,可较好地实现多属性查找。文中描述了多属性查找算法,分析了网络性能,该网络旨在降低资源查找的跳数,因此文中主要分析网络查找跳数。实验表明,资源查找跳数得到优化,达到了预期效果。     

A Population-Membrane-System-Inspired Evolutionary Algorithm for Distribution Network Reconfiguration

This paper proposes a Population- membrane-system-inspired evolutionary algorithm （PM- SIEA）, which is designed by using a population P system and a Quantum-inspired evolutionary algorithm （QIEA）. PMSIEA uses the population P system with three cells to organize three variants of QIEAs, where communications between cells are performed at the level of genes, instead of the level of individuals reported in the existing membrane algorithms. This work provides a useful framework for synthesizing different algorithms at macro level and exchanging genic information at micro scale. Experimental results conduced on knapsack problems show that PMSIEA is superior to four representative QIEAs and our previous work with respect to the quality of solutions and the elapsed time. We also use PMSIEA to solve the optimal distribution system reconfiguration problem in power systems for minimizing the power loss.     

A Note on BIBO Stability of Linear Discrete-Space Systems

The cornerstone of the theory of discrete-space single-input single-output linear systems is the idea that every such system has an input-output map H that can be represented by a convolution or the familiar generalization of a convolution. This thinking involves an oversight which, under some mild assumptions, was recently corrected by adding an additional term to the representation. Here we give a criterion for the bounded-input bounded-output stability of such systems.     

迭代法求解电路方程组的Matlab软件实现

本文研究了求解电路方程组的三种迭代法,并介绍了如何使用MATLAB软件编写相关程序来求解电路方程组,并举出具体案例对三种迭代法进行具体的说明,旨在为求解电路方程组的教学提供一种新的学习思路.     

MPI＋OpenMP混合编程模型在大规模三对角线性方程组求解中的应用

分布式共享存储系统的特点是每个节点内是共享存储的,而节点间是分布式存储.为了更好地利用这种多级体系结构,讨论了MPI＋OpenMP混合编程模型的性能及实现方法,建立了大规模三对角线性方程组的MPI＋OpenMP混合并行算法,并在上海大学高性能计算集群上与单纯MPI算法进行了性能方面的比较.结果表明,MPI＋OpenMP混合并行算法具有更好的加速比和扩展性.     

基于集对分析的P2P网络安全中的信誉度改进算法

P2P安全是P2P技术中的关键问题.传统基于信誉度的投票选举方法能够很好地反映P2P网络中未知节点的表现,为该节点的可信度提供可靠依据,但该方法并未将P2P网络中的不确定因素考虑进去.集对分析理论是一种研究不确定性问题的数学方法.本文提出了一种基于节点的不确定性的P2P网络信誉度安全机制,并采用集对分析方法对信誉度进行了定量分析.最后对两种算法做了对比分析,指出了改进算法的优越性.     

一种基于动态分配模式求解三对角线性方程组的并行算法

分析了双向并行分裂DPP算法存在空闲等待、通信阻塞以及冗余计算等方面的不足,并在此基础上提出一种基于动态分配模式求解三对角线性方程组的并行算法.该算法摒弃了DPP算法平均分配方程组的模式和完成向中间通信后必须消除所有下(上)对角元素的方式,而采用基于运算和通信参数的动态分布模式以及仅适量消元的方法,从而在保持通信畅通的前提下,充分利用计算与通信重叠技术,减少处理机空闲等待和冗余计算.最后分析了新算法的理论性能,并在IBMRS60000机群上进行了数值实验.实验结果表明,该算法的效率较DPP算法有较大提高.     

光通信系统中一种低复杂度的AP-QC-LDPC码新颖构造方法

提出了一种低复杂度的具有等差数列(AP)特性的准循环低密度奇偶校验(QC-LDPC)码构造方法,该方法结构简单,节省了存储空间,可根据实际需要灵活地改变码长和码率.利用该方法构造出的AP-QC-LDPC(4599,4307)码的校验矩阵的每行元素为等差数列,且公差单调递增,所以该校验矩阵不含有4环.仿真结果表明:在误码率(BER)为10-6时,该AP-QC-LDPC(4599,4307)码比ITU-T G.975中的RS(255,239)码和ITU-T G.975.1中LDPC(32640,30592)码的净编码增益(NCG)分别改善了约2.19和1.48 dB,比基于有限域乘群的eIRA-QC-LDPC(4599,4307)码和QC-LDPC(3780,3540)码的净编码增益分别提高了约0.16和0.2dB.该方法构造的AP-QC-LDPC(4599,4307)码具有更好的纠错性能,能更好地适应光通信系统的需求.     

UbiFOS: A Small Real‐Time Operating System for Embedded Systems

The ubiquitous flexible operating system (UbiFOS) is a real‐time operating system designed for cost‐conscious, low‐power, small to medium‐sized embedded systems such as cellular phones, MP3 players, and wearable computers. It offers efficient real‐time operating system services like multi‐task scheduling, memory management, inter‐task communication and synchronization, and timers while keeping the kernel size to just a few to tens of kilobytes. For flexibility, UbiFOS uses various task scheduling policies such as cyclic time‐slice (round‐robin), priority‐based preemption with round‐robin, priority‐based preemptive, and bitmap. When there are less than 64 tasks, bitmap scheduling is the best policy. The scheduling overhead is under 9 µs on the ARM926EJ processor. UbiFOS also provides the flexibility for user to select from several inter‐task communication techniques according to their applications. We ported UbiFOS on the ARM9‐based DVD player (20 kB), the Calm16‐based MP3 player (under 7 kB), and the ATmega128‐based ubiquitous sensor node (under 6 kB). Also, we adopted the dynamic power management (DPM) scheme. Comparative experimental results show that UbiFOS could save energy up to 30% using DPM.