Sampled-data control for linear time-delay distributed parameter systems

Some real systems have spatiotemporal dynamics and are time-delay distributed parameter systems (DPSs). The existence of time-delay may lead to system instability. The analysis and design of DPSs with time-delay is essentially more complicated. To take into account the factor of time-delay and fully enjoy the benefits of the digital technology in control engineering, it is a theoretical and practical value to consider the sampled-data control (SDC) problem of DPSs with time-delay. However, there are few attempts to solve the SDC problem of time-delay DPSs. In this paper, we introduce a SDC for linear time-delay DPSs described by parabolic partial differential equations (PDEs). A SDC design is developed in the formulation of spatial linear matrix inequalities (LMIs) by constructing an appropriate Lyapunov functional, which can stabilize exponentially the time-delay DPSs. This stabilization condition can be applied to either slowing-varying time delay or fast-varying one. Finally, simulation results of a numerical example are provided to illustrate the effectiveness of the proposed method.     

JX4C DPS中IKONOS立体像对的一体化处理

本文简要介绍了IKONOS遥感卫星系统及其立体影像数据的特点,给出了IKONOS影像立体模型的构建原理与方法,探讨了IKONOS影像的区域网平差方案,对少控制或无控制测图做了初步分析。随后,描述了JX4C数字摄影测量工作站中对IKONOS立体影像从数据预处理、单模型定向、区域网平差到区域DLG、DEM/DSM、DOM等测绘产品生产的一体化处理流程。文章最后指出,以IKONOS为代表的高分辨率遥感影像在测绘领域的广泛应用标志着卫星摄影测量与制图时代的开始。     

全数字摄影测量与4D技术探讨

本通过京福高速公路和福州、三明、厦门地区“４Ｄ”产品试验方案探讨全数字摄影测量集成技术,以ＶｉｒｔｕｏＺｏ ＮＴ系统为例重点剖析ＤＰＳ核心技术及其指标,并讨论“４Ｄ”产品工艺与实现技术线路。     

管道外防护涂层抗划伤性能评估研究

通过划伤试验和测试数据的可靠度分析，研究了三种管道外防护层的抗划伤性能。结果表明，DPs涂层抗划伤性能明显优于3-PE和FBE涂层，增加涂层厚度可以减少涂层被划伤至基体的危险；不同厂家生产的同类型材料所涂敷的涂层的抗划伤性能存在明显差异．划伤重量是影响划伤深度的最主要因素；所采用的划伤试验方法基本上能够反映现场实际情况，适合工程应用中对管道外防护涂层及其原材料抗划伤性能的评定和筛选。     

用DPS分析再生纤维织物服用性能

应用DPS软件对再生纤维织物的服用性能进行对应分析研究,在知觉图上将再生纤维织物结构参数和服用性能之间的关系直观地表达出来,为新型再生纤维织物开发提供了依据。     

移动通信机房基站绿色节能减排方法探讨

从2/3G共站建设、BBU+RRU分布式基站建设、替换机房G2 BSC、双密度载频应用、提高基站设备覆盖效率、DPS技术、AMR技术应用、移动网络IP化等方面入手,探讨通过网规网优实现移动通信机房基站节能减排的方法。     

JC-3196测试系统检修分析

在设备维修中分析的过程就是查找故障的过程,因此设备维修的关键就是懂得对设备故障如何进行分析,但是要想准确的对设备故障进行分析,就必须详细了解设备的硬件组成及各部分的工作原理。因此文章从简单介绍JC-3196测试系统的硬件组成及各部分的工作原理开始,然后再介绍几种设备常见故障,并通过这些故障的现象对其进行详细的检修分析。文章从四个方面对其进行说明:JC-3196测试系统的硬件组成、各部分源的主要功能及工作方式、故障分析、维修的注意事项。     

A study on the effects of ESFAS STI modification on the unavailability of ESF actuated components

The nuclear industry has made so great efforts to attain safe and economically viable Nuclear Power Plants all over the world. Probabilistic Safety Assessment (PSA) applications are required now more than ever in order to operate Nuclear Power Plants.In this paper, the unavailability model of Engineered Safety Feature (ESF) actuated components, which is part of the Korean Standard Nuclear Power Plant (KSNPP) PSA model, is used to analyze the effects of Surveillance Test Interval (STI) extension of Engineered Safety Feature Actuation System (ESFAS) on the unavailability of the ESF actuated components.To develop a more accurate and realistic PSA model, the loop controller modules of Plant Control System (PCS) are also modeled on the KSNPP PSA model. The fault tree developed by each ESF actuated component includes the component failure, ESFAS signal failure, and loop controller module failure of PCS. When the ESFAS STI is extended from one month to three months, the unavailability of ESF actuated components partially increased by 10%. This shows the STI extension of ESFAS has minor effects on the unavailability of the ESF actuated components. The effects of ESFAS STI extension of KSNPP on the unavailability of the ESF actuated components as well as Core Damage Frequency (CDF) and Large Early Release Frequency (LERF) is less than expected. That result indirectly indicates that the ESFAS in KSNPP is designed well enough to extend the ESFAS STI.     

Geoway DPS数字摄影测量软件在生产数字线划图DLG中的应用

通过对Geoway DPS采编一体化数字摄影测量软件在广西1∶10000 DLG(全要素及核心要素)生产工作中的实践应用,对数据采集(更新)的生产技术、生产工艺等技术问题提出见解和实施方案,为保证广西1∶10000 DLG生产的顺利实施提供有效的技术手段和建设性意见。     

水泥砂浆体中三向压力传感器的测量特性

 确定三向压力传感器实测应力与其周围待测介质初始应力的关系是实现其应力测量的必要条件。为了解三向压力传感器在实际应用中的测量特性,利用RMT岩石力学试验系统对自行研发的三向压力传感器进行标定,研究各个传感面的重复性和线性度,得到各个传感面的标定系数。以水泥砂浆为材料,浇筑制成嵌入三向压力传感器的立方体试样(边长：600 mm),并利用自行研制的真三轴试验加载装置,研究重复荷载作用下水泥砂浆体中三向压力传感器实测应力随外部加载应力状态的变化规律。水泥砂浆体的孔隙结构使得三向压力传感器的实测应力存在滞后现象,但在重复荷载作用下,水泥砂浆体中的孔隙结构逐渐被压密,三向压力传感器的实测应力曲线逐渐趋于稳定。静水应力状态加载条件下,三向压力传感器的实测应力与其对应方向的加载应力呈线性相关关系;非静水应力条件下,三向压力传感器的实测应力不仅与其对应方向的加载应力呈线性相关关系,而且与其对应方向的加载应力与其它两个方向的加载应力之差,也成线性相关关系。在此基础之上,提出了用于描述介质初始应力状态对三向压力传感器实测应力影响规律的数学关系。