Real-time modeling of power networks

The use of large digital computers in control centers has made it possible to track the changing conditions in the power system with a mathematical model in the computer. This real-time model can be used to assess the security of the present system as well as to check out possible control strategies. In this paper the various steps in constructing the model from the real-time measurements are described. These steps include the determination of the network topology, the estimation of the network state, and the approximate modeling of the unobservable (external) network. This paper also discusses the checks for observability and bad measurements, and the calculation of bus load forecast factors and generator penalty factors.     

Real-time 3D thermal modeling of a magnetically levitated planar actuator

A transient thermal model used to monitor the temperature distribution in real-time in a long-stroke moving-magnet planar actuator is presented. The temperature distribution in the stator coils of the planar actuator depends on the trajectory of the levitated magnet plate as the set of active coils changes with the position of the translator. Using the presented real-time model, the transient thermal behavior can be investigated. Using this thermal model, the commutation algorithm of the planar actuator is adjusted to actively limit the temperature of the coils, and better spread the temperature over the stator coils.     

Cross polarization diagnostics

The cross polarized radar cross section of simple axially symmetric objects is shown to be related to transverse body dimensions and the severity of any edges.     

加热炉炉内跟踪数据模型优化

本文介绍了莱钢宽厚板加热炉炉内跟踪信息模型.通过对炉内跟踪信息模型的优化,实现主从数据模块无缝对接操作,实时对钢坯炉内信息进行调整,并达到不影响正常生产的要求.     

BioMEMS--生物医学诊断和治疗的桥梁

生物微机电系统(BioMEMS)集微传感器、微驱动器、微流体系统、微光学系统及微机械元件于一体，广泛应用于生物学、医学和生物医学工程等领域，是一个新的交叉研究学科。本文概述了BioMEMS的研究内容和发展方向，给出了部分BioMEMS研究结果。     

Reliability with imperfect diagnostics

This paper considers the reliability of systems that accumulate faults throughout their lifetime because of imperfect diagnostics. Several experiments are referenced that show the difficulty of achieving a 100 percent diagnostic level. After explaining the assumptions and constructing the reliability estimation method, the paper proceeds to a graphical trade-off analysis that considers the effect of imperfect diagnostics on three traditional ways of achieving higher reliability: lower component fault rate, more redundancy, and redundancy with reconfiguration.     

OFDR diagnostics for fibre and integrated-optic systems

Optical frequency-domain reflectometry (OFDR) shows promise as a diagnostic tool for high-resolution ranging in fibre/integrated-optic systems, and in high-resolution distributed fibre-optic sensors. We discuss some signal processing aspects of this technology, potential performance and application.     

Applied optical diagnostics of semiconductors

Optical techniques are finding an increasing number of applications for the characterization of semiconductor materials and devices. An introduction to this field is given, starting with a review of the principles behind the most popular techniques. The techniques are illustrated by examining specific examples of technological importance taken from the recent literature. They include several examples of identification of materials, mapping of wafers with high spatial resolution, and in-situ probing of growth and of device operation     

Dipole admittance for magnetoplasma diagnostics

A method is presented for calculating the admittance of a short thin dipole antenna in a cold collisional magnetoplasma. The theory is quasi-static, and the results are slightly more accurate than in previous analyses. Numerical calculations of admittance as a function of frequency are presented for several different orientations of the dipole with respect to the magnetic field. For any orientation the calculations show that the plasma frequency and the upper hybrid frequency can be readily identified.     

Network management using expert diagnostics

Networks have become a key component of the corporate infrastructure. Managing the networks, which often carry a diverse set of information (e.g. voice, data, video) over a diverse set of media (e.g. wire, cable, RF) with a mixture of owned and leased transmission assets that are often geographically distributed and run a diverse set of protocols, is a major challenge. One of the most promising techniques applies expert system approaches to the management of networks. Copyright © 1999 John Wiley & Sons, Ltd.     

Microfabricated devices for genetic diagnostics

This paper presents a review of microfabricated devices for genetic diagnostics. Genetic diagnostics are powerful technology drivers and excellent candidate applications for miniaturization technologies because the demand for inexpensive genetic information is essentially unlimited, and the cost and time for the diagnostic decreases with sample volume. Genetic information is stored in long DNA molecules in solution. This information is processed and extracted using a series of enzymatic and other chemical reactions well known in molecular biology. Processing of DNA molecules in the microscale hence requires the implementation of microfluidic devices capable of handling, mixing, thermal cycling, separating, and detecting nano- and picoliter liquid samples. This paper discusses some of the fundamental macroscale protocols used for genetic analyses and how these processes scale down to microscopic volumes. The construction and performance of microfluidic devices of DNA amplification, separation, hybridization, and detection are discussed, showing that so far, no fundamental impediments exist for genetic diagnostics based on microelectromechanical systems. Some of the unresolved storage and packaging issues and future challenges for the practical implementation of these devices are also presented     

Phase tomography in microwave diagnostics

The phase tomogram is shown to be a useful mode of representation for microwave images. Dependent on the approximations and a priori knowledge used in the reconstruction process, the phase image indicates the distribution of attenuation of a dielectric object.     

Technical diagnostics for power apparatus

The purpose of technical diagnostics and preventive maintenance for power apparatus should be recognized in protecting equipment against failures and malfunctions. Due to an earlier detection of incipient faults in power apparatus economic benefits can be gained. This is important to reduce operating costs.     

电镜诊断学的兴起与发展

电子显微镜用于临床研究和诊断已有四十余年历史，它在这方面所起的作用是重大的，现已成为临床疾病诊断中不可缺少的重要工具之一，并已建立了新兴的电镜诊断学。目前认为要发展电镜诊断学，必须加强三个平台的建设，走联合道路，组成相应的电镜诊断中心，做到优势互补，一定能为我国电镜诊断学的发展作出新贡献。     

A multifrequency gyrotron for plasma heating and diagnostics

Gyrotrons are regarded as a necessary component of any modern fusion machine. They are presently used primarily to heat the electron component of the plasma. However, gyrotrons can be utilized also to drive the current, to stabilize MHD modes, to measure the ion temperature by means of the collective Thomson scattering, to mention just a view plasma diagnostic purposes. In this work we present a design of a multifrequency gyrotron, i.e., a gyrotron which generates RF power simultaneously at several frequencies and discuss possible applications of such tubes.     

Automotive signal diagnostics using wavelets and machine learning

In this paper, we describe an intelligent signal analysis system employing the wavelet transformation in the solution of vehicle engine diagnosis problems. Vehicle engine diagnosis often involves multiple signal analysis. The developed system first partitions a leading signal into small segments representing physical events or states based on wavelet multi-resolution analysis. Second, by applying the segmentation result of the leading signal to the other signals, the detailed properties of each segment, including inter-signal relationships, are extracted to form a feature vector. Finally, a fuzzy intelligent system is used to learn diagnostic features from a training set containing feature vectors extracted from signal segments at various vehicle states. The fuzzy system applies its diagnostic knowledge to classify signals as abnormal or normal. The implementation of the system is described and experiment results are presented     

ATPG and diagnostics for boards implementing boundary scan

The emergence of the IEEE 1149.1 boundary scan standard facilitates structured approaches for board partitioning, allowing test generation and execution on localized logic clusters. This article discusses a study conducted on 1149.1 board designs to examine issues associated with board-level Automatic Test-Pattern Generation (ATPG) and diagnostics.     

Spectrally discriminating time-resolved and space-related X-ray plasma diagnostics

The experimental study of laser-produced plasmas, particularly those relevant to laser fusion, has long motivated the development of new X-ray plasma diagnostic techniques. This paper summarizes the application of a number of novel space-resolved and time-resolved X-ray diagnostic systems to the study of plasmas produced by the 1 beam 0.35 μm GDL facility, and by the 24 beam 1.05 μm OMEGA facility at the Laboratory for Laser Energetics. Two time-resolving X-ray spectrometers are described, one utilizing a transmission grating as a dispersive element, the other employing an array ofK-edge filters for spectral discrimination. A transmission grating is also used in conjunction with a Kirkpatrick-Baez microscope to provide spectrally dispersed high spatial resolution images of the laser-produced plasmas. The usefulness of these instruments in measuring specific plasma parameters and identifying particular spectral features, in some cases with the aid of other diagnostic instrumentation, is illustrated.     

VBE标准及其在实时动态图像实时显示中的应用

本文介绍了视频电子标准协会(VESA)制定的VBE标准,结合该标准,通过对基于嵌入式平台的遥感图像实时滚动显示系统的三种软件实现方案进行对比,凸显了该标准的在硬件资源占用上的优势,最后,本文给出了一个基于嵌入式计算机平台和VBE标准的遥感图像实时动态显示系统的实施方案。     

红外图像实时生成系统的实时性实现

针对红外图像实时生成系统的实时性需求,从高帧频图像实时生成、图像数据实时传输、实时控制三个方面对系统中与实时性相关的关键环节进行了探讨。通过选用高品质的图形工作站、搭建高速通信网络、图像实时生成软件的实时性设计和实时操作系统VxWorks与硬件的无缝连接等措施,使系统实现了高实时性。论证表明,采用这些措施可以在Windows XP操作平台上生成128×128像元、200 Hz以上帧频的逼真红外图像。