板坯连铸结晶器电动缸非正弦振动技术与应用

总结了结晶器振动装置的结构型式、振动方式,介绍了宁钢结晶器振动装置存在的问题、改造方案和改造内容。分析了结晶器正弦与非正弦振动波形曲线,并介绍了结晶器电动缸非正弦振动系统组成、优点、工作原理、技术指标及在宁钢的应用效果。     

A review of oscillation mechanisms and the role of the precessing vortex core (PVC) in swirl combustion systems

This paper reviews the occurrence of the precessing vortex core (PVC) and other instabilities, which occur in, swirl combustion systems whilst identifying mechanisms, which allows coupling between the acoustics, combustion and swirling flow dynamics to occur.     

Boundary integral equations as applied to an oscillating bubble near a fluid-fluid interface

A new method is presented to describe the behaviour of an oscillating bubble near a fluid-fluid interface. Such a situation can be found for example in underwater explosions (near muddy bottoms) or in bubbles generated near two (biological) fluids separated by a membrane. The Laplace equation is assumed to be valid in both fluids. The fluids can have different density ratios. A relationship between the two velocity potentials just above and below the fluid-fluid interface can be used to update the co-ordinates of the new interface at the next time step. The boundary integral method is then used for both fluids. With the resulting equations the normal velocities on the interface and the bubble are obtained. Depending on initial distances of the bubble from the fluid-fluid interface and density ratios, the bubbles can develop jets towards or away from this interface. Gravity can be important for bubbles with larger dimensions.     

Applying the Oscillation Test Strategy to FPAA’s Configurable Analog Blocks

This paper presents the application of the oscillation test methodology as an alternative to test configurable analog blocks of Field Programmable Analog Arrays. The blocks of the device under test are first configured to behave as oscillators. Then, the output frequency and amplitude are observed to obtain the signature of the fault-free circuit. During test, this signature is compared to the actual output signal. Experimental results show the effectiveness of the method in detecting parametric and large deviation faults of the tested components.A paper based on this work was presented at the Fourth IEEE Latin American Test Workshop, Natal, Brazil, February 2003.Tiago Roberto Balen was born in Erechim, Brazil, in 1979. He received the Electrical Engineering degree from the Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil in 2004. At present, he is M.Sc. student in the Electrical Engineering Department and works in the Prototyping and Test Laboratory at UFRGS. His research interests include analog and mixed-signal design and test, built-in self-test and design-for-testability. He has published papers on FPAA testing in important conferences, such as the VLSI Test Symposium (VTS) and the International Test Conference (ITC).Antonio Andrade, Jr., received the Electrical Engineering degree from the Universidade Federal da Bahia (UFBA), Salvador, Brazil, in 2003, and is currently pursuing the M.Sc. degree at Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil. His experience as a researcher includes the design of a temperature controller using thermo-resistive sensors and FPGA prototyping, at the Instrumentation Laboratory in UFBA, in 2001, a 2-month scholarship from Laboratorio Nacional de Luz Sincrotron (LNLS), Campinas, Brazil, in 2002, and 2 years as a graduate student at the Prototyping and Test Laboratory, at UFRGS. His primary research topics include Mixed-Signal Circuit and Systems Testing as well as fast system prototyping in platforms as FPGAs and FPAAs, having published papers in important conferences, such as the VLSI Test Symposium (VTS) and International Test Conference (ITC), in the field of FPAA testing.Florence Azaïs received the Ph.D. degree in electrical engineering from the University of Montpellier, France in 1996. She is currently working in the Microelectronics department of the Laboratory of Computer Science, Robotics and Microelectronics of Montpellier (LIRMM) as a researcher of the National Council of Scientific Research (CNRS). Since 1993, she has been interested in the general domain of test and reliability of integrated circuits and systems. Her main research interests include fault modeling, analog and mixed-signal circuit testing, MEMS testing, reliability and failure analysis of integrated systems. She has authored or co-authored over 80 international papers on these topics. She also served as a member of the Program Committee of several international conferences (DATE, ICCD, ETS, IMSTW, LATW).Marcelo Lubaszewski received the Electrical Engineering and M.Sc. degrees from the Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil, in 1986 and 1990, respectively. In 1994, he received the Ph.D. degree from the Institut National Polytechnique de Grenoble (INPG), France. In 2001, he joined the Laboratoire dInformatique, Robotique et Microélectronique de Montpellier in France as an Invited Researcher for 3 months and, in 2004, the Instituto de Microelectrónica de Sevilla (IMSE) in Spain for 1 year. He is currently with UFRGS, where he has been an Associate Professor since 1990. His primary research interests include design and test of mixed-signal, micro-electro-mechanical and core-based systems, self-checking and fault-tolerant architectures, and computer-aided testing. He has published over 150 papers in international journals and conferences on these topics. Dr. Lubaszewski has served as the general chair or program chair of the Symposium on Integrated Circuits and Systems Design (SBCCI) and of the Latin American Test Workshop (LATW), and as a member of the Organizing or the Program Committee of the VLSI Conference, the International Mixed-Signals Testing Workshop, the Asian Test Symposium, the European Design and Test Conference, the Design of Complex Integrated Systems Conference, the European Test Symposium and the GHz/Gbps Test Workshop. He has also served as a Guest Editor of the Journal of Electronic Testing: Theory and Applications and as an Associate Editor of the Design and Test of Computers Magazine.Michel Renovell is head of the Microelectronics Department at LIRMM (Laboratory of Computer Science, Automation and Microelectronics of Montpellier). His research interests include: Fault modeling, Analog testing and FPGA testing. He is Vice-Chair of the IEEE TTTC (Test Technology Technical Committee). He is a member of the editorial board of JETTA and the editorial board of IEEE Design & Test. Michel has been General Chair of the International Mixed Signal Testing Workshop IMSTW2000, the Field Programmable Logic Conference FPL2002 and the European Test Symposium ETS2004.     

基于改进收敛交叉映射的厂级振荡源诊断

由于噪声、周期性、非线性和非平稳性的干扰,现有的大多数因果分析方法在工业过程控制系统的应用中往往是不可靠和不准确的。为提高厂级振荡源定位的性能,提出了一种基于改进收敛交叉映射的因果关系检测方法。首先,指出噪声和周期性对因果关系检测的不利影响。其次,将经验模态分解和去趋势波动分析相结合,实现了振荡信号去噪。然后,通过奇异谱分析有效地去除信号的周期性。利用收敛交叉映射可以对去噪去周期后的信号进行分析,进而准确地定位厂级振荡的源头。仿真结果表明,所提方法能提高过程控制系统中厂级振荡源定位的准确性。     

北黑电网振荡问题的研究

针对黑龙江省北县电网实际振荡事故，应用特征值法进行计算分析，在得到与实际情况相吻合的仿真计算基础之上，对系统内各种调节器及其参数与系统主特征值之间的关系进行了广泛深入的研究，从而提出了通过修改西沟水电厂机组调速系统参数bt、Td和Tn来增加系统阻尼，解决目前北黑电网存在的振荡问题，最后通过计算给出了各参数最佳定值范围。     

一种带有隔离技术的高频压控振荡器

提出一种带有谐振电路隔离技术的电感电容压控振荡器。该技术通过两个三极管将谐振电路和其它电路隔离,减少了谐振电路中等效电容的大小,进而增加了电感电容压控振荡器的振荡频率。提出的电感电容压控振荡器采用华虹NEC的0．181xmSiGeBiCMOS工艺,振荡频率达到12．35GHz。在其它性能相同的情况下,提出的电感电容压控振荡器的振荡频率比典型的电感电容压控振荡器的振荡频率高出20％以上。     

一类非线性微分差分方程解的存在唯一性与振动性

研究一类非线性微分差分方程解的性态，把它的解的存在性、唯一性和振动性与差分方程的相应性质对应起来．得到几个比较型定理．从而推广了Gyori.I和Ladas．G[1]的某些结果．     

基于改进扰动观察法的光伏发电最大功率跟踪研究

在光伏发电系统中光伏电池板是产生电能的装置,光伏电池运行受外界环境温度、辐照度等因素的影响,呈现出典型的非线性特征。外界条件不同时,光伏电池可运行在不同且唯一的最大功率点上。分析了最常用的最大功率点跟踪方法。并给出了一种新的最大功率跟踪方法,新方法能够快速跟踪到最大功率点,并且解决了跟踪过程的振荡问题。最后通过Matlab/Simulink仿真验证了控制有效性,得到了较好的输出波形。