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关键词：国土资源管理信息系统 J2EE 工作流组件技术

论文对新时期国土资源管理信息化建设的特点进行了分析,提出了国土资源管理信息化建设的一些思路,认为应该把事务性处理模块与审批性管理模块分离,同时在数据库设计上保持高度一致。论文讨论了采用企业级的J2EE架构,即采用MVC(Model/View/Control)构建国土资源管理信息系统的总体技术路线与实现方法。论文最后分析了国土资源管理信息系统建设应注意的问题。

关于任意反馈结构下的固定模

关键词：固定模　　反馈结构　　关联反馈　　分散控制系统　　极小元　　System　　充要条　　Control　　理论与应用　　北京航空学院

本文讨论了当分散控制系统存在分散固定模时如何增加关联反馈项,使在新的反馈结构下无固定模,且使增加的关联反馈项尽可能少或满足一些特性的问题。为此我们得到了一些充要条件。

A Framework for Designing Grid Workflow System based on Ontology

Grid computing is innovative information service infrastructure for dynamic and distributed resources sharing and collaboration. Grid workflow is used to handle tasks with control and data dependencies,and plays an important role in Grid computing. It is essential to design an appropriate model to satisfy the distributed and heterogeneous workflow systems that must be flexible, reusable, dynamic feature in higher level. As the idea of the designing and composing semantic Web services, a method for designing Grid workflow system framework based on ontology is proposed in this paper. Four types of Ontology concept are defined: Workflow_Meta Ontology,Model Driven Method Ontology, Knowledge Representation Ontology and Date Types Ontology,and the particular description of their functions,constitutes and relations with each other are given.Based on this framework, the Grid workflow systems will have stronger capability to deal with their cooperation and dynamic composition with each other.

An Intelligent Pressure Sensor Using Rough Set Neural Networks

关键词：Intelligent pressure sensor　　rough set theory　　neural networks.

The nonlinear response characteristics of a capacitive pressure sensor (CPS) changes when ambient temperature changes widely. In such condition, the calibration becomes difficult and to obtain accurate pressure readout, appropriate compensation to the CPS characteristics is needed. We propose an intelligent CPS using rough set neural networks (RSNN) to provide self-calibration and compensation. The proposed model based on rough set and neural networks can provide the calibrated response characteristics irrespective of change in the sensor characteristics due to change in ambient temperature using rough set theory and compensates the nonlinearity in the respond characteristics using neural networks. Simulation results show that this model can estimate the pressure with a maximum full-scale error of ±2.5 percent over a variation of temperature from -50℃ to 150℃.

Study on thermal safety design index in high temperature coal mine

关键词：High temperature coal mine　　Thermal safety　　Design index　　Heat safety model

With the extension of mine exploitation,thermal disaster becomes more and more serious,which is the sixth nature disaster succeeding by water,fire ,gas,coal dust and roof.So,measures must be taken to improve the conditions of working environment.Non-mechanism cooling and mechanism cooling have been adopted in coal mine,especially to the mechanism cooling,the reasonable quantity of cooling need to be defined,which rely on the thermal safety index.The design of cooling in coal mine in China adopts dry-bulb temperature 26 ℃ as the single index at all times,but the index can't reflect the degree of heat disaster in detail.So,the new index needs to be defined to satisfy the requirement of thermal safety and saving energy.This paper adopts heat balance equation to study the thermal safety in coal mine,with the experiment,the heat safety model suitable to miners in China has been established,according to the model,new heat safety index has been defined.Under the new index,the miners'physiological status has been tested,the result shows that the miner's physiological status is better after one shift,so,it is a reasonable index that suitable to coal mine in China.

Ventilation information management of coal mine and visualization technique

关键词：The system of ventilation information management　　Visualization　　Mine safety

The paper analyses the characteristics of mine ventilation system,gas and airflow regularities,discusses the method of visualization about ventilation system and ventilation safety information management,and designs the model of visual system for mine ventilation system.The model designed to actualize the fusion of ventilation and ventilation database,graphic processing of mine ventilation safety information and achieve the aim of visualization.The authors also point out application of visualization technique is one of the ways to solve the problems about safety in the ventilation safety of mines.

Reliable Guaranteed Cost Control of Uncertain Systems with Time-Varying State Delay and Nonlinear Perturbations

The reliable guaranteed cost control problem of uncertain systems with time-varying state delay and nonlinear perturbations are considered. A sufficient condition for the existence of reliable guaranteed cost controllers is derived in the term of LMIs. Furthermore, a convex optimization problem with LMI constraints is formulated to design the optimal reliable guaranteed cost controller which minimizes the upper bound of the closed-loop system cost. Numerical example illustrated the proposed method.

Model Establishment and Parameter Calculation of Permanent Magnet-Biased Hybrid Magnetic Bearing with Magnet in Rotor

A new kind of permanent magnet-biased hybrid magnetic bearing (MB) with magnet in rotor is developed in order to reduce the bearing's volume and magnetic coupling between X and Y degrees-of-freedom. Its principle structure is introduced and magnetic circuit model is established, on the basis of which, the parameters such as maximum force, force to current ratio, force to displacement ratio and the magnetic coupling are calculated. 3-D FEM is adopted to verify the above analysis. The MB has been used successfully in the suspension of an attitude control/energy storage flywheel with angular momentum of 15Nms at speed of 30,000rpm, satisfying the demand of good stability and low power loss.

The Hopf Bifurcation and Quasi-Periodic Characters of Inverse Pendulum Motion

关键词：inverse pendulum　　stability　　Hopf bifurcation　　quasi-periodic

Inverse pendulum is a typical multi-variable nonlinear system. In this paper, the calculus equation of the nonlinear motion is made based on the Lagrange equation and the nature of the first Hopf bifurcation is obtained through stability analysis. By analysis of phase diagrams and time-series diagrams of different pendulum length l, mass m and elasticity K, It is shown that the inverse pendulum mechanical system embodies such nonlinear dynamics characteristics as Hopf bifurcation and quasi-periodic. When K/(mgl)1, the phase path is always a closed ring-like curve circling the central only stationary state A(0,0).Wben K/(mgl)<1, the phase path becomes a closed ring-like curve circling different symmetrical stationary state. The number of stationary state multiplies with the unceasing reduction of K/(mgl),and finally the system enters the quasi-periodic state.

The Design of a High Cost Performance Piston outside Diameter Auto-measuring and Grouping System

关键词：auto-measuring　　grouping　　PC104　　the process capacity　　control chart

The method and the performance of measuring the piston determine the quality and cost of the piston manufactured. Therefore, a simple, economic piston outside diameter automeasuring and grouping system is presented in this paper. Based on the industrial PC104 bus structure, it can not only measure and group the pistons, but also can manage the data. Meanwhile, through the modern statistical process analysis and control technology, the quality of the manufacturing process can be analysed and controlled. The well-fitted software and mechanotronics structure enables the system to be simple and reduces the whole cost.

Design and Implement of Web-based Three-dimensional Coalmine Safety Monitoring Visualization Control

关键词：coalmine　　3D　　control　　safety monitor　　web

Roadways, ventilators, air gates, and gas sensors can be shown in the two-dimensional sketch maps or the vector maps in many web-based ventilation monitoring and controlling systems. However, these safety management information systems seldom have abilities to display and query gas monitoring data in web-based three-dimensional visualization environment. To accomplish the goal of 3D visualization on the web, a web-based three-dimensional coalmine safety monitoring visualization control, called VRMineCtrl, is designed and developed. Users can build the ventilation database, download the VRMineCtrl control from the web server, query the latest gas monitoring data from the database, look over the running status and related parameters of ventilator, air gate and gas sensor, position and pre-alarm abnormal gas content spots, check the history curves of gas sensor. In this paper, three-tiered Browser/Server architecture of Coalmine Safety Management System is constructed at first. Several key approaches are explained in detail, including writing the real-time data into the ventilation database, accessing the ventilation database by Web Engine, modeling the 3D geometric object and data organizing, selecting the 3D objects and simulating the ventilator running status. An application example is given finally. The design and implement of 3D coalmine safety monitoring control offer a newly simple visualization tool for coalmine safety production and management.

越江盾构隧道纵向排烟的数值模拟研究

关键词：shield tunnel　　longitudinal smoke extraction　　control wind velocity

本文根据南京长江盾构隧道横断面及纵断面设计情况,采用火灾数值分析软件FDS,对盾构隧道纵向排烟情况下不同位置处发生火灾进行了数值模拟,比较了火灾情况下不通风和控制不同风速下火灾烟流随时间的扩散场分布情况.模拟结果表明,在不通风情况下,火灾后烟流向上坡方向的蔓延速度远大于下坡方向,下坡隧道中控制烟流流动的速度应大于上坡隧道中控制烟流流动的速度.对于南京长江隧道,下坡段的临界风速为3.5 m/s,上坡段的临界风速为3.0 m/s,该风速与两种临界风速理论计算值均有差异.从工程应用的角度出发,火灾后下坡段控制风速可取为2.5～3.0 m/s,而上坡段控制风速可取为2.5～3.0 m/s,火灾通风设计可以该风速作为参考.

二维非结构网格无粘流场数值计算

关键词：非结构网格　　迎风差分

The 2-D Euler equations are discretized with a cell-cefltered finite-volume approach and three-stages Runge-Kutta scheme on unstructured triangle mesh. Roe''s characteristicbased flux-difference splitting is used to determine the fiux through the border of control domain. Subcritical and supercritical fiows past NACA OO12 airfoil are calculated to study the convergence, accuracy and efficiency of the algorithm. The results have been validated against structured-grid solutions.

Design of Atmospheric Hypoxic Chamber Based on Fuzzy Adaptive Control

Contrary to the problem of plateau acute reaction caused by the low oxygen partial pressure, we designed a simulated altitude environment atmospheric hypoxia chamber. The control system is based on fu

Modeling and Control of a Stratospheric Satellite

Trajectory tracking control of a stratospheric satellite is investigated in this paper. A simplified dynamical model for the stratospheric satellite is established based on the Lagrange equation to de

Low-cost IMU/Odometer/GPS Integrated Navigation Aided with Two Antennae Heading Measurement for Land Vehicle Application

For the guidance, control and navigation of autonomous vehicles, both positioning and orientation are important for mission success and surveillance. Global positioning system (GPS) and strapdown iner

Control of Juncture Flows

关键词：Juncture Flow　　Horseshoe Vortex　　Controlling Cylinders　　Diameter Reynolds Number　　Smoke Wire Flow Visualization

Flow around obstacle mounted on flat surface is a common feature of many engineering applications e.g.heat exchangers,ground building junction,wing-body junction,turbine blade-rotor junction and submarine hull-fuselage.The strong adverse pressure gradient developed at the juncture region separates the incoming flow,may cause it to roll-up and produce a vortical structure known asHorse Shoe Vortex.It causes the juncture portion to scour,produces high level of turbulence and vibration and also generates a lot of heat. Various methods have been devised to date,to completely eliminate or to reduce the strength of this undesirable phenomenon.In the present study the horse shoe vortex caused by a circular cylinder mounted on a flat plate,is controlled by placing small circular,square and triangular cross sectional cylinders(Controlling cylinders) at different locations upstream of the Juncture region.The visualization results reveal that by placing theControlling Cylindersat appropriate distance from the leading edge of the Juncture the vortex can be eliminated completely or its strength can be reduced significantly.More over the behavior of different cross sectional shape controlling cylinders with same wind ward width and Aspect ratio is different for same Reynolds numbers and at same upstream position.

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