两维时间域上的实时程序语义

超稠密计算模型是实时系统的一种重要抽象模型．该文首先简要介绍一种两维的超稠密时间域及在该域上定义的一种区间逻辑,然后用一个并行模型语言（类Ｏｃｃａｍ 语言）讨论用这种逻辑定义并行语言（在超稠密模型中）的时间语义的问题,最后讨论了在这种语义框架中实时系统性质的描述     

A semantics for a class of non-deterministic and causal production system programs

We define a class of function-free rule-based production system (PS) programs that exhibit non-deterministic and/or causal behavior. We develop a fixpoint semantics and an equivalent declarative semantics for these programs. The criterion to recognize the class of non-deterministic causal (NDC) PS programs is based upon extending and relaxing the concept of stratification, to partition the rules of the program. Unlike strict stratification, this relaxed stratification criterion allows a more flexible partitioning of the rules and admits programs whose execution is non-deterministic or causal or both. The fixpoint semantics is based upon a monotonic fixpoint operator which guarantees that the execution of the program will terminate. Each fixpoint corresponds to a minimal database of answers for the NDC PS program. Since the execution of the program is non-deterministic, several fixpoints may be obtained. To obtain a declarative meaning for the PS program, we associate a normal logic program with each NDC PS program. We use the generalized disjunctive well-founded semantics to provide a meaning to the normal logic program Through these semantics, a well-founded state is associated with and a set of possible extensions, each of which are minimal models for the well-founded state, are obtained. We show that the fixpoint semantics for the NDC PS programs is sound and complete with respect to the declarative semantics for the corresponding normal logic program .This research is partially sponsored by the National Science Foundation under grant IRI-9008208 and by the Institute for Advanced Computer Studies.     

A Consistent Causality-Based View on a Timed Process Algebra Including Urgent Interactions

This paper discusses a timed variant of a process algebra akin to LOTOS, baptized UPA, in a causality-based setting. Two timed features are incorporated—a delay function which constrains the occurrence time of atomic actions and an urgency operator that forces (local or synchronized) actions to happen urgently. Timeouts are typical urgent phenomena. A novel timed extension of event structures is introduced and used as a vehicle to provide a denotational causality-based semantics for UPA. Recursion is dealt with by using standard fixpoint theory. In addition, an operational semantics is presented based on separate time- and action-transitions that is shown to be consistent with the event structure semantics. An interleaving semantics for UPA is immediately obtained from the operational semantics. By adopting this dual approach the well-developed timed interleaving view is extended with a consistent timed partial order view and a comparison is facilitated of the partial order model and the variety of existing (interleaved) timed process algebras.     

The semantics and verification of timed service choreography

As a service composition and coordination language, the service choreography gives the global and neutral view on the collaboration among a collection of highly distributed services involving multiple different organizations or heterogeneous independent processes. In this paper, we extend the service choreography by introducing the explicit time activity, which can be used to specify and reason about the timed behaviour of Web service choreography. Then we explore an execution model for the proposed timed service choreography which possesses several novel features, such as timed activity, choreography composition, exception handling and finalization. Furthermore, a set of mapping rules is elaborately designed to translate the timed choreography into communicating sequential programs processes, thus the corresponding simulation and verification of Web services choreographies with timing restrictions can be carried out in the model checker process analysis toolkit. The case study shows that our approach is both effective and practical.     

多任务的异步并发在梯级AGC系统中的实现

探讨了实时条件下多任务的程序设计技术,并给出了实现方案与基本编程模型.针对并发程序设计并发性、共享性的特点,对引入多线程机制如何提高软件系统处理速度,以及可能带来的问题进行充分研究,并结合三峡梯级AGC工程应用实际找出了瓶颈及制约因素,提出了针对性的解决策略.实际运行验证表明,该方案充分利用了UNIX小型机的资源优势,有效提高系统整体性能,满足了AGC系统对实时性的要求.     

离散捕食系统的持久性和全局稳定性

研究一类带有Beddington．DeAngelis功能性反应和时滞的多维离散食饵．捕食系统的持久性和全局稳定性。利用差分方程的比较原理,给出了系统持久性的充分条件;应用估值方法推导得到系统全局稳定性的充分条件;使用不动点理论,证明了系统周期解的存在性和全局稳定性。     

On the asymptotic execution time of multi-tasked processes on tandem processors

Consider an ordered set of processes, each consisting of tasks, to be processed by a system of K processors in tandem. Each process, immediately after havings its i-th (1≤i<K) task served by the i-th processor, is queued up on a first-come-first-served basis for processing of its (i+1)-st task by the (i+1)-st processor, until all its tasks have been served. Define the execution time to be the time to serve all the processes in the set.

Given that the processes form a stationary and ergodic sequence, as far as the processing times of the tasks are concernec, the asymptotic execution time is first explicitly computed, as the number of processes tends to infinity. This is done by using subadditive ergodic theory and certain results from the stability theory of tandem queueing networks. Then, design issues of such systems are discussed.     

石化企业制造执行系统及应用

国内石化企业与国外相比在生产管理上尚存在一定差距,这给企业取得竞争优势造成巨大的瓶颈。制造执行系统对于提升企业生产管理水平,促进企业信息化建设具有至关重要的作用,是缩小该差距的有效途径。国外已开发很多优秀的制造执行系统软件,但其在国内应用方面尚有不足,不能较好地适应中国企业生产管理的实际情况。本文针对国内石化企业制造执行系统的需求特点,结合企业业务流程知识,建立统一的工厂模型,设计出以企业数据集成平台为支撑,集生产计划、生产统计、生产调度、操作管理、物料移动、能源管理、关键绩效指标、综合展示等业务模块为一体的面向石化企业的制造执行系统。分析了该系统在石化企业的实际应用效果。实践表明,该方案具有良好的可重构性、可集成性和敏捷性。系统在石化企业中可与原有的信息系统相互支持,实现企业内信息的合理有效集成,增强了业务透明度,提高了工作效率,从而极大提高企业信息管理水平并实现更加高效和优化的生产。系统的成功实施对于相关企业的信息化建设具有重要的指导和借鉴意义。     

GPS接受系统的研制和应用

介绍了对全球定位接受系统具体的工作原理,通过全球定位接受系统实验数据分析,系统精度及全向棒状天线全向方向性得到验证,采用与弹共形的微带天线,从而实现全球定位技术在弹道修正系统中应用。     

N-Prolog and equivalence of logic programs

The aim of this work is to develop a declarative semantics for N-Prolog with negation as failure. N-Prolog is an extension of Prolog proposed by Gabbay and Reyle (1984, 1985), which allows for occurrences of nested implications in both goals and clauses. Our starting point is an operational semantics of the language defined by means of top-down derivation trees. Negation as finite failure can be naturally introduced in this context. A goal-G may be inferred from a database if every top-down derivation of G from the database finitely fails, i.e., contains a failure node at finite height.Our purpose is to give a logical interpretation of the underlying operational semantics. In the present work (Part 1) we take into consideration only the basic problems of determining such an interpretation, so that our analysis will concentrate on the propositional case. Nevertheless we give an intuitive account of how to extend our results to a first order language. A full treatment of N-Prolog with quantifiers will be deferred to the second part of this work.Our main contribution to the logical understanding of N-Prolog is the development of a notion of modal completion for programs, or databases. N-Prolog deductions turn out to be sound and complete with respect to such completions. More exactly, we introduce a natural modal three-valued logic PK and we prove that a goal is derivable from a propositional program if and only if it is implied by the completion of the program in the logic PK. This result holds for arbitrary programs. We assume no syntactic restriction, such as stratification (Apt et al. 1988; Bonner and McCarty 1990). In particular, we allow for arbitrary recursion through negation.Our semantical analysis heavily relies on a notion of intensional equivalence for programs and goals. This notion is naturally induced by the operational semantics, and is preserved under substitution of equivalent subexpressions. Basing on this substitution property we develop a theory of normal forms of programs and goals. Every program can be effectively transformed into an equivalent program in normal form. From the simple and uniform structure of programs in normal form one may directly define the completion.     

MAHRU-M: A mobile humanoid robot platform based on a dual-network control system and coordinated task execution

This paper introduces a mobile humanoid robot platform able to execute various services for humans in their everyday environments. For service in more intelligent and varied environments, the control system of a robot must operate efficiently to ensure a coordinated robot system. We enhanced the efficiency of the control system by developing a dual-network control system. The network system consists of two communication protocols: high-speed IEEE 1394, and a highly stable Controller Area Network (CAN). A service framework is also introduced for the coordinated task execution by a humanoid robot. To execute given tasks, various sub-systems of the robot were coordinated effectively by this system. Performance assessments of the presented framework and the proposed control system are experimentally conducted. MAHRU-M, as a platform for a mobile humanoid robot, recognizes the designated object. The object’s pose is calculated by performing model-based object tracking using a particle filter with back projection-based sampling. A unique approach is used to solve the human-like arm inverse kinematics, allowing the control system to generate smooth trajectories for each joint of the humanoid robot. A mean-shift algorithm using bilateral filtering is also used for real-time and robust object tracking. The results of the experiment show that a robot can execute its services efficiently in human workspaces such as an office or a home.     

钢铁企业生产指挥系统集成研究

以酒泉钢铁集团信息化建设工程为背景,基于企业管理模式由金字塔式转向扁平化的思路,建立了经营决策支持中心、生产指挥中心和交易中心的扁平化管理模式。应用钢铁企业的BPS／MES／PCS综合自动化系统体系结构,提出一种与扁平化管理相适应的生产指挥系统集成解决方案,为酒钢的信息化建设工程的实施提供了可行的集成框架。     

On Some Vagaries of Vagueness and Information

The presence of vagueness in scientific theories (in particular, to those related to and connected with the management of information) is briefly analyzed. We consider, firstly, the problem whether vague predicates can be adequately represented by existing formal theories. A negative answer to this question produces, as a by-product, the suggestion that a good semantics for fuzzy sets can be offered by the notion of distance from idealized items. Secondly, some questions connected with the adequacy of theories of information to the multifaceted informal notion of information suggest to afford this problem within an enlarged dynamical setting.     

基于VC++和FORTRAN混合编程的优化系统设计

用VC＋＋和FORTRAN语言混合编程的方法进行优化系统的设计,不但可以方便地进行优化算法的设计和友好的人机界面设计,还能够实现并行地进行软件系统的开发,可以有效地缩短程序设计时间.对外壳函数调用FORTRAN生成的可执行文件时系统出现的异步执行问题和“黑屏”问题提出了解决办法,最后给出了优化系统的设计实例,验证了该方法的可行性和有效性.     

General pattern of global system conflicts and global threats of the 21st century

Data on global conflicts took place from 750 B.C. up to now are analyzed and their general pattern is revealed. An attempt is made to foresee the next global conflict called the conflict of the 21st century. Its nature and main characteristics are analyzed. Main global threats are listed, and their impact on five groups of countries is determined using cluster analysis. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 5, pp. 87–99, September–October 2007.     

小城镇移动电子政务系统的设计与实现

为了满足小城镇政府工作人员在地域分散的农村地区实地办公的需要,通过调查基层政府各机构的业务处理现状,概括出基层政府野外办公的共性功能集,基于无线通讯技术、GPS全球定位技术和嵌入式开发技术集成,以低成本PDA,智能手机等移动终端设备为运行平台,开发完成了小城镇移动电子政务系统.该系统可实现农村经济、社会人文等信息的在线和离线查询,政务工作的现场审批处理,突发事件现场信息采集与上传,终端位置的实时定位与跟踪等远程办公事务处理,为基层政府工作人员乡下现场办公的实现提供了工具基础.     

热成像传感器动静态成像系统设计

为测试研究室开发的热成像传感器性能与成像质量,设计了成像传感器动静态成像与图像算法验证系统.系统能够捕获成像传感器静态图像,并能实时成像,具有通用性.数据的采集和处理应用FPGA+ DSP开发板实现.数据传输基于CY7C68013芯片以块同步数据传输方式,实现了无缝同步方式高速传输.基于VS2010编程环境和开源机器视觉库编写了接收、存储以及处理图像数据应用程序平台.测试表明:系统能够以40 Mbyte/s速率数据传输,用于实验室开发的热成像传感器工作良好.