Computing Triangular Systems and Regular Systems

A previous algorithm of computing simple systems is modified and extended to compute triangular systems and regular systems from any given polynomial system. The resulting algorithms, based on the computation of subresultant regular subchains, have a simple structure and are efficient in practice. Preliminary experiments indicate that they perform at least as well as some of the known algorithms. Several properties about regular systems are also proved.     

实时数据库系统中的嵌套事务

传统的原子事务是由一个平坦数据库操作序列组成的,事 务的执行具有ACID(Atomicity, Consistency, Isolation, Durability)特性.然而,在实时 应用环境下,这些却不太适用.该文提出了一种支持实时应用的嵌套事务模型,给出了嵌套事 务的特性及正确性标准,着重对嵌套实时事务的优先级分派与并发控制协议进行了讨论.     

Computing Accumulated Delays in Real-time Systems

We present a verification algorithm for duration properties of real-time systems. While simple real-time properties constrain the total elapsed time between events, duration properties constrain the accumulated satisfaction time of state predicates. We formalize the concept of durations by introducing duration measures for timed automata. A duration measure assigns to each finite run of a timed automaton a real number —the duration of the run— which may be the accumulated satisfaction time of a state predicate along the run. Given a timed automaton with a duration measure, an initial and a final state, and an arithmetic constraint, the duration-bounded reachability problem asks if there is a run of the automaton from the initial state to the final state such that the duration of the run satisfies the constraint. Our main result is an (optimal) PSPACE decision procedure for the duration-bounded reachability problem.     

模糊关系系统的反馈控制

以开环系统模糊关系模型为基础,讨论了模糊关系系统反馈控制器的设计.给出了一种 反馈控制律,分析了闭环系统的若干性质.提出的反馈控制律便于实施,且同时适用于跟踪及 调节问题.     

Towards a Theoretical Framework of Autonomous Systems Underpinned by Intelligence and Systems Sciences

Autonomous systems are an emerging AI technology functioning without human intervention underpinned by the latest advances in intelligence,cognition,computer,and systems sciences.This paper explores the intelligent and mathematical foundations of autonomous systems.It focuses on structural and behavioral properties that constitute the intelligent power of autonomous systems.It explains how system intelligence aggregates from reflexive,imperative,adaptive intelligence to autonomous and cognitive intelligence.A hierarchical intelligence model(HIM)is introduced to elaborate the evolution of human and system intelligence as an inductive process.The properties of system autonomy are formally analyzed towards a wide range of applications in computational intelligence and systems engineering.Emerging paradigms of autonomous systems including brain-inspired systems,cognitive robots,and autonomous knowledge learning systems are described.Advances in autonomous systems will pave a way towards highly intelligent machines for augmenting human capabilities.     

Linear Periodic Systems Over Dioids

A specification of the linear system theory over dioids is proposed for periodic systems. Using the conventional periodic system theory as a guideline, we study periodic systems for which the underlying algebraic structure is a dioid. The focus is on representations (impulse response and state model) associated with such systems, the properties of these representations as well as the state space realization.     

动态系统的一致同余安全

研究动态系统的安全问题．针对动态系统运行时间配置的可变特性，引入了动态系统的进程代数模型和复杂动态系统概念，定义了动态系统的一致安全性质和一致同余安全性质．基于观察同余等价，构造了一类一致同余安全模型．本文证明，动态系统的安全性质是一致安全性质，而对于复杂动态系统，其安全性质是一致同余安全性质．     

反应系统的连续时序逻辑表示和验证

引进一个称为LTLC的连续时间时序逻辑，用来对反应系统进行规范与验证．LTLC的一个重要特点是它能在统一的逻辑框架下表示反应系统及其性质，这样就可将系统与性质问的满足关系转化为逻辑公式间的蕴涵关系．同时，采用非负实数集作为时间域还使我们可以利用标准的存在量词来表示变量隐藏，并可用逻辑蕴涵来表示反应系统间的求精关系．该文首先给出了LTLC的一个简单介绍，然后讨论了如何使用LTLC对反应系统进行表示与推理，最后证明了一个关于LTLC的可判定性结果．此结果可用于有穷状态反应系统的自动验证．     

Solving Hankel Systems over the Integers

A new algorithm is presented for computing the solution of a Hankel system with integer entries by means of structured matrix techniques. By combining subresultant theory and factorization properties of Hankel matrices, we prove that this algorithm has a Boolean sequential cost which is almost optimal among the algorithms based on fast integer LU factorization.     

多变量模糊神经网络控制器的研究

提出一种MIMO系统的模糊神经网络控制器结构,阐述了基本设计思想和具体算法过程。应用实例仿真结果表明,它可用于控制强耦合带时延多变量系统,并使系统具有良好的动态和静态性能。     

模糊滑动模态控制系统的性质分析

根据滑动模态原理,将模糊控制系统的输入量简化为广义跟踪误差的一个超平面,并基于三角形的非线性发语言变量的隶属度,分析了模糊控制系统的某些性质,表明在系统稳定性、稳态误差等指标方面,模糊控制器优于一般的ＰＩＤ控制器。     

信息物理融合系统控制软件的统计模型检验

信息物理融合系统常采用嵌入式实时多任务系统作为其控制软件,这类软件的并发和非确定性给验证带来了困难.提出了一种利用统计模型检验技术分析多任务系统的功能正确性的方法.该方法构造的时间自动机模型以模块化的方式描述了实时多任务系统中的主要成分,包括实时操作系统、周期性任务、偶发任务、共享资源以及物理环境,能够展现多任务系统的细粒度的运行过程及其对物理环境的实时响应.应用该方法分析了玉兔号月球车控制软件的一个早期版本,发现了系统运行中出现的一个特殊错误,识别了实际系统出现错误的条件,再现了出现错误的场景.     

策略驱动的自配置系统形式化建模及分析验证

使计算机系统具有自主配置的能力,可以解决复杂系统面临配置管理难度高和强度大的问题。本文针对策略驱动的自配置系统的配置问题,提出采用CPN建模技术对该类系统进行建模、分析与验证,保证系统自配置过程的正确性;分析了策略驱动自配置系统的基本结构,构造出该类系统的CPN模型,引入CTL的扩展--ASK-CTL描述系统配置过程中具备的性质;最后用CPN Tools2．2．0进行仿真与验证。     

广义信息系统及其决策规则

提出一类更广泛的信息系统,称其为广义信息系统．它包含了完备信息系统、不完备信息系统和多值信息系统．给出了广义信息系统集合近似的概念、方法和相关性质．讨论了广义信息决策系统的决策描述形式．这种决策描述形式易于转化为Skolem标准型,可以直接应用于人工智能的归结推理．     

Using Program Transformations to Provide Safety Properties for Real-Time Systems

The process of showing that a program satisfies some particular properties with respect to its specification is called program verification. Axiomatic semantics is a verification method that makes assertions describing properties about the states of a program. There exists a transformation from the assertions of a program's verification proof to executable assertions. The latter may be embedded in the program to make it fault tolerant. An axiomatic proof system for concurrent programs is applied to generate executable assertions in a real time distributed environment. A train set example is used as modelproblem.     

定位系统在智能交通系统中的应用

文章讨论了智能交通系统（ITS）以及定位系统在ITS中的作用。目前存在两类不同的定位系统,第一类是基于卫星的定位系统,第二类是基于地面的定位系统,每类系统各有其特点。首先讨论这两类系统在成本、精度和覆盖范围方面的特性,然后介绍系统的主要类型以及在移动通信网络中的定位技术。最后,介绍了两类定位系统相结合的定位技术A-GPS。     

一种新的数字化混沌扰动方案

在混沌系统中施加主动扰动是混沌从理论研究向实际应用转化的有效手段。本文提出了一种对数字化混沌系统进行扰动的可行方案,该方案选择性地扩散数字化混沌系统的部分变量,以达到对整个系统的扰动。扰动后系统可生成具有均匀的不变分布和良好密码学特性的伪随机序列。实验的数据表明该扰动方案有效地补偿了数字化混沌系统动力学特性的退化。     

Superstable Linear Control Systems. I. Analysis

The notion of superstability of linear control systems was introduced. Superstability which is a sufficient condition for stability was formulated in terms of linear constraints on the entries of a matrix or the coefficients of a characteristic polynomial. In the first part of the paper, the properties of superstable systems were studied. The norms of solutions were proved to decrease exponentially monotonically in the absence of perturbations, and the solutions were proved to be uniformly bounded in the presence of bounded perturbations. A generalization to nonlinear and time varying systems was discussed. Spectral properties of superstable systems were studied. For interval matrices, a complete solution was given to the problem of robust superstability.     

延时双线性系统参数估计的方块脉冲函数分析法

本文采用方块脉冲函数的优良运算性质,推导出一种简便有效的分析延时双线性系统参 数估计问题的新方法,与其它方法相比,具有运算特别简单的特点.     

Application Specific Transaction Management in Multidatabase Systems

We present a transaction model for multidatabase systems with autonomous component systems, coined heterogeneous 3-level transactions. It has become evident that in such a system the requirements of guaranteeing full ACID properties and full local autonomy can not be reconciled. In the heterogeneous 3-level transaction model, semantics of actions and specific properties of the architecture of multidatabase systems and of applications are utilized to define application specific compromises between these competing goals. We consider different definitions of conflicts between actions together with application specific sets of allowed (autonomous) local transactions and global subtransactions. A formal model for serializability is given. It is proven that heterogeneous 3-level transactions guarantee all consistency constraints that are ensured in serial executions. In contrast to most other models, we do not require data to be partitioned into global and local data. In particular, heterogeneous 3-level transactions even allow the same data to be updated by local and global transactions in parallel, if these updates are found to be semantically non-conflicting. Recovery is handled by inverse actions. We present a formal framework for this approach which is fully integrated into serializability theory by considering inverse actions as ordinary actions. This has an important impact on the relationship of concurrency control and recovery in our model: By changing the definition of conflicts between actions in order to tailor the model according to application needs, recovery is implicitly affected and no further explicit adaptation of recovery algorithms is necessary. The heterogeneous 3-level transaction model assumes component database systems to support ACID transaction properties. Further properties of local transactions or interfaces of the component database systems are not required. We describe a prototype implementation of heterogeneous 3-level transactions in the object-oriented database system VODAK.