基于Labview与容栅传感器的液位测控系统

为了实现液位测控中对精度要求高的需求,提出了一种基于容栅传感器和LabVIEW的液位精密测控系统,利用容栅传感器输出的电容信号经信号调理模块输入MSP430单片机处理,并通过PID算法精密控制液位,采用LabVIEW设计系统监控界面程序,实现系统数据的显示、存储、绘图以及人机控制等功能;通过测试数据表明该液位测控系统测量精度高,精度达0.05ml,操作简单;该系统还可配装为数显测定仪和物体密度测量仪,人机界面良好,成本低,易推广。     

基于ARM的摊铺机行驶测控模块的硬件设计

介绍了摊铺机行驶系统的控制方案，结合摊铺机行驶系统的功能要求及LPC2138的特点，实现了摊铺机行驶系统数字控制器测控模块的硬件设计，包括测控模块总体结构、LPC2138微控制器、模拟量输入通道、开关量输入通道、开关量输出通道、PWM输出模块、通信接口。讨论了测控模块的抗干扰技术。     

航空发动机轴承试验机测控系统的设计

为了分析新型材料航空发动机轴承的失效原因并提高轴承的使用寿命和可靠性,研制了一台能够模拟航空发动机工况的轴承疲劳试验机,设计了基于西门子S7-1500PLC的远程测控系统.测控系统通过PLC控制模块、驱动器和变频器等,实现了动力系统、润滑系统和加载系统的控制和试验载荷谱线的自动运行.试验主参数信号通过高速高性能模拟量A/D模块进行采集,并通过以太网传输至上位机.上位机软件对数据进行实时处理、存储和绘制曲线.通过试验验证,所设计的轴承试验机测控系统设计合理、运行可靠,为航空发动机轴承寿命研究和性能试验提供了基础平台和数据支撑.     

基于.NET的流程图绘制程序的设计与实现

对流程图绘制程序的设计进行了详细、整体的阐述,介绍了.NET环境下GDI 绘图机制,分析了流程模块的绘制、插入、修改、智能拼接等功能的实现原理,利用树形结构数据存贮流程记录信息,并结合XML与ADO.NET数据交互技术,实现了流程绘制、信息存贮、数据转换、图形输出等功能。     

基于.NET的流程图绘制程序的设计与实现

对流程图绘制程序的设计进行了详细、整体的阐述，介绍了．NET环境下GDI＋绘图机制，分析了流程模块的绘制、插入、修改、智能拼接等功能的实现原理，利用树形结构数据存贮流程记录信息，并结合XML与ADO-NET数据交互技术，实现了流程绘制、信息存贮、数据转换、图形输出等功能。     

基于AT89C2051的远端数据智能测控模块

介绍了远端数据智能测控模块的具体开发,给出了硬件电路和软件框图,分析了模块测控的原理,指明其运行环境。多输入多输出测控模块设计简单,易于实现,解决了RS485总线上要挂结很多测量模块的矛盾,减少了成本。     

船舶测控设备校验装置数据采集系统的设计

船舶测控设备校验装置需要完成多个测量参数的数据采集和处理,本文利用VC编写程序对工业控制计算机PCI卡进行数据操作,实现了Windows下对工业控制计算机模拟量输入／输出PCI卡、数字量输入／输出PCI卡、通讯PCI卡的数据的采集和处理,最终完成了校验装置数据采集系统的功能。     

编程疑难问题解答

如何利用VB的Win32API调用实现数据报表(Data Report)的横、纵向输出控制问题的提出 工作中用VB6开发工程计算程序时,由于工程算法的不够成熟,需要通过大量经验数据作为输入条件,通过分析中间及最终结果以调整算法。由于输入、输出参数众多,将数据存放在Access数据库中,并通过VB6新增工具DataReport设计数据报表,通过Data Environment(数据环境)与存放输入参数、输出结果的数据库相关联,并编写模块输出报表,以便于分析数据,调整算法。     

测控设备web网络服务器化研究

为实现利用Internet自带的客户端浏览器对现场设备进行远程监控的目的,设计并实施了新型web网络服务器化远程测控系统。系统中测控设备内嵌嵌入式web服务器,既能自身作为测控终端直接采集数据,又能通过CAN总线与其他测控器进行组网,实现类似网关的功能。硬件设计主要包括：嵌入式web服务器模块、测控器模块以及其接口模块设计与实施。软件设计主要选用Linux操作系统和嵌入式web服务器Boa实现CGI技术,设计添加CAN控制器驱动程序后完成IE浏览器与嵌入式web服务器以及测控器三者之间的通信。利用该系统进行温度测试,实验成功并能满足实时性,充分表明利用Internet浏览器、嵌入式web服务器组建并控制CAN网络的新型远程测控系统的先进性与可行性。     

自动摊铺机测控模块的硬件设计

主要介绍了自动摊铺机测控模块的总体结构 ,并分别讨论了模拟量输入 /输出接口电路、数字量输入 /输出接口电路和通信电路     

求连续搅拌釜式反应器控制系统数学模型的计算机程序

信号流图是一种表示复杂控制系统中各变量间关系的很好的方法。利用 MASON 增益公式可以求得信号流图中输入变量与输出变量间的关系—即输入节点到输出节点的总传输。本文通过连续搅拌釜式反应器控制系统来探讨在计算机上实现 MASON 增益公式的方法,利用这种方法编制的 FORTRAN 程序可以用来求解信号流图两点间的总传输或数学关系式。程序在HP-1000机上调试通过。     

基于OWL-S文档的Web服务测试用例生成

若从使用者的角度测试Web服务,只能从服务的接口文档中提取信息进行测试工作.现有工作提出通过分析文档中的输入或输出参数获取测试数据的方法.利用OWL-S文档中的输入输出参数信息生成初始的测试数据,同时充分利用文档中的服务过程信息,提取出服务的控制流程图,据此约简测试数据,生成最终的测试用例,从而提高测试用例的生成效率,降低测试成本.     

Structured debugging using a domain specific language

A structured approach to debugging is presented based on restricting the class of programs that can be written. This is achieved by defining a domain specific language, eliminating control flow by using aggregate operations and eliminating side effects by using an applicative language as a base. The domain specific language is realized by defining domain specific operators as extensions to the base language; a set of operators are defined in the paper for data processing applications. The debugging strategy consists of setting up a sequence of input/output transformations; this process takes the input to the output in partial stages so that the correctness of each transformation relative to its input and output set can be verified. The approach is illustrated by a simple data processing problem.     

Detecting value-based scalar dependence

Precise value-based data dependence analysis for scalars is useful for advanced compiler optimizations. The new method presented here for flow and output dependence uses Factored Use and Def chains (FUD chains), our interpretation and extension of Static Single Assignment. It is precise with respect to conditional control flow and dependence vectors. Our method detects dependences which are independent with respect to arbitrary loop nesting, as well as loop-carried dependences. A loop-carried dependence is further classified as being carried from the previous iteration, with distance 1, or from any previous iteration, with direction <. This precision cannot be achieved by traditional analysis, such as dominator information or reaching definitions. To compute anti- and input dependence, we use Factored Redef-Use chains, which are related to FUD chains. We are not aware of any prior work which explicitly deals with scalar data dependence utilizing a sparse graph representation. A preliminary version of this paper appeared in theSeventh Anual Workshop on Languages and Compilers for Parallel Computing, August 1994. Supported in part by NSF Grant CCR-9113885 and a grant from Intel Corporation and the Oregon Advanced Computing Institute.     

识别恶意软件中的加密函数

针对恶意软件通过加密函数规避安全检测和流量分析这一问题,提出了一种识别恶意软件中加密函数的方法。通过识别恶意软件动态执行路径中的循环、循环的输入和输出参数,构建恶意软件的动态循环数据流图,通过循环数据流图提取循环的输入和输出参数集合,设计已知加密函数的参考实现对循环输入集合中的元素进行运算,判断输出是否能够匹配输出集合中的元素从而识别恶意软件中的加密函数。实验证明此分析方法能够分析严重混淆的恶意软件其传输载荷所采用的加密函数。     

基于ECA的温室控制系统测量与执行层模型

现代农业温室中,控制设备和数据采集设备硬件种类繁多、接口复杂多样。该文在采用分层结构分布式温室控制系统的测量与执行层中,定义参数变量表描述硬件输入/输出接口。基于事件驱动方式,将ECA规则用于数据采集和控制动作输出过程开发,并将多个ECA规则定义和组合用于描述复杂控制动作时序。测量与执行层封装控制设备的硬件接口差异,使系统具有组态配置功能,并将一些复杂控制驱动过程分解成几个简单的控制子过程来组合实现。     

Nonlinear modelling and control of the flow over aerofoils using CFD simulations

A simulation based approach for nonlinear dynamical modelling and feedback control of the drag to lift ratio for aerofoils is investigated through case studies involving NACA 23012, ag13 and b737a aerofoils. The flow around the aerofoils is studied via numerical solutions of the 2D Navier–Stokes (NS) equations. A standard computational fluid dynamics (CFD) solver is extended to be able to measure desired feedback values and to apply a control input to the flow field. The proposed modelling and control approach is based on first determining the measurement points and injection points on the aerofoil for the control input. Then, to estimate the dynamical model, some input–output data are collected by injecting a chirp input flow to the field and saving the measurement data. Next a Hammerstein–Wiener (HW) type nonlinear dynamical model of the flow field is estimated using system identification. For control design, the nonlinear part of the model is eliminated by means of inverse functions, followed by the application of automated tuning methods to the linear part to obtain the closed-loop system. The results show that the designed feedback control system can reduce the drag to lift ratio considerably as compared to the unactuated case.     

XML文档在卫星任务规划系统中的应用研究

介绍了卫星任务规划系统的总体开发流程,通过分析卫星任务规划系统的输入输出数据的属性,发现传统的关系型数据在任务规划系统中所存在缺点,将XML模式用于描述卫星任务规划系统中的输入输出数据结构和数据内容,实现了卫星任务规划输入输出数据的标准化,展现了对输入输出数据进行标准化描述的XML文档格式.通过对输入输出数据的标准化描述,任务规划系统能够摆脱数据库的限制,实现跨领域、跨平台的应用.为今后任务规划系统向B/S结构的转变打下了基础.     

An algebra for data flow diagram process decomposition

Data flow diagram process decomposition, as applied in the analysis phase of software engineering, is a top-down method that takes a process, and its input and output data flows, and logically implements the process as a network of smaller processes. The decomposition is generally performed in an ad hoc manner by an analyst applying heuristics, expertise, and knowledge to the problem. An algebra that formalizes process decomposition is presented using the De Marco representation scheme. In this algebra, the analyst relates the disjoint input and output sets of a single process by specifying the elements of an input/output connectivity matrix. A directed acyclic graph is constructed from the matrix and is the decomposition of the process. The graph basis, grammar matrix, and graph interpretations, and the operators of the algebra are discussed. A decomposition procedure for applying the algebra, prototype, and production tools and outlook are also discussed     

A finite volume scheme for solving elliptic boundary value problems on composite grids

This paper presents a new dataflow graph model, where only data tokens are allowed to flow. First we introduce a High-Level Dataflow System (HLDS) to describe a formal dataflow graph model, then we present a homogeneous HLDS (hHLDS) that formally describes our proposal. In this proposal the dataflow graph is obtained by employing only actors with homogeneous I/O conditions, that is, each actor, which executes an elemental operation, is characterised by having one output and two input arcs. Even though no control tokens are allowed, i.e. no T-gate, merge, and switch actors are present in this model, it is always possible to obtain dataflow graphs, which represent any programming structure and whose behaviour is well-behaved. As homogeneous I/O conditions are a severe restriction to represent the flow of a computation and the token flow in such dataflow graphs is completely asynchronous, proof is given to guarantee their determinacy. The main advantage of this representation is that it maps directly to hardware through a one-to-one correspondence between actors of the model and Functional Units of a dataflow machine.