采用智能单元式控制台实现计算机联锁系统的人机交互

智能单元式控制台具有抗干扰能力强等特点,是一种可选的计算机联锁人机交互设备.本文在比较控制台与标准计算机设备两种操作方式的优缺点后,提出了与操作表示机实现双通道以太网连接的硬件方案,给出了完整的通信内容及在定时发送、即时发送和心跳检测相结合的通信策略下的异常处理机制和双机切换逻辑.同时采用增加模式切换按钮的方法实现了控制台和鼠标两种操作模式的人工切换和有效隔离.     

调度集中系统中双机热备机制的实现

研究了调度集中系统中双机热备的实现方案.给出了故障定义原则,详细讨论了双机之间的基本倒机原则及倒机优先级,并进一步给出了双机热备机制的工作原理流程图,列出了双机热备机制中的状态转移.本文提出的双机热备实现方案已在FZj-CTC型分散自律调度集中系统中得到了应用,应用结果表明,本方案切实可用.对于高可靠的应用要求,本文具有良好的借鉴作用.     

双机全自动转换

为提高通信与导航系统的可靠性,地面发射机采用用一备一双机全自动转换措施。本文将论述双机全自动转换设备的功能要求、实现方法、原理和逻辑关系。按照这种逻辑原理,能够实现发射机的自动转换,加电程序及对机器保安措施,并提出电路设计选用集成电路和半导体逻辑元件来代替继电器。实践证明,这种双机自动转换设备性能稳定可靠,易于生产。     

"组态王"工控软件及其在循环水泵自控系统中的应用

针对电厂发电机组循环水泵运行上的特殊性，而设计的自控装置，上位机采用具有先进的软件设计思想的“组态王6．0”，下位机选择ModiconPLC模块，采用双机备热系统，实现了对发电机循环水泵的所需设备、操作过程、运行状态等方面的反动控制。     

双机容错系统中基于FPGA容错控制器的设计

根据双机容错系统故障检测和诊断、仲裁技术的常用方案及特点,结合某在研双机容错系统,提出了一种基于FPGA容错控制器的设计方案.仲裁模块作为容错控制器的核心模块,可根据双机工作的监测信号负责完成主备机切换功能.为了实现软硬件心跳故障监控功能,在FPGA内嵌了WTD模块.同时,全局时钟引用于各个模块后,良好消除了输出信号的毛刺问题.实验结果表明, 该设计方案满足系统要求,可靠性较好.     

基于PLC的控制系统在污水处理中的应用

给出了一套适合污水处理的以PLC为核心的分布式控制系统，并分析了该系统的整体结构、任务分配、控制方式和一些重要控制回路的实施。与其它PLC控制系统相比，本系统硬件结构采用两台上位机互为热备，主要现场控制站PLC双机热备以及通讯网络冗余，从而保证了整个系统的高可靠性和稳定性。实际运行证明：该系统成功地实现了污水处理的自动化控制，提高了污水处理设备的运行效率和管理水平。     

中波广播发射台计算机实时监控管理系统

为了实现中波广播发射台播出设备控制和网络管理，系统采用上位机和下位机两级计算机监控，上位机完成与九台下位机的实时通信，接收各下位机采集的现场数据，实时处理，实时显示整个发射台系统９包括主备发射机，音频加工设备，供配电系统）的工作状态，由于该系统能按节目播时时间表定时开机和关机，判主机有故障时，秒级切换到备机工作，从而减少了故障停播时间，提高了广播节目播出质量。     

一种FDP双机热备方案

提出了一种基于Tru64 Unix的FDP双机热备方案，就主从切换，主从数据同步和校验方面描述其实现原理，并根据通用的可靠性标准论证了其可靠性。     

Win2000下oracle双机热备的一种简单方法

数据库服务器双机热备解决方案是根据用户需求实现数据库安全的一种高性能高可靠性的解决方案，本文以windows2000下Oracle双机热备系统的工作机制，探讨一种简单的数据库双机热备的解决方案。     

双机热备系统在政府网络中的应用

近几年来,许多政府部门应用计算机网络系统实现办公自动化,安全问题成为了首要问题,利用双机热备保证网络服务的畅通,并介绍了双机热备系统的实现方法。     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to