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Inverter-Based Diesel Generator emulator for the Study of Frequency Variations in a Laboratory-Scale Autonomous Power System

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Energy and Power Engineering 2013年第3期5卷 274-283页

作者： Miguel Torres Luiz A. C. Lopes Department of Electrical and Computer Engineering Concordia University Montreal Canada

This paper presents the modeling, simulation and practical implementation of an inverter-based diesel generator emulator. The main purpose of this emulator is for the study of frequency variations in diesel-based autonomous power systems in a laboratory environment where the operation of a real diesel generator is not possible. The emulator basically consists in a voltage source inverter with a second order output filter which voltage references are given by the model of the diesel generator. The control of the emulator is based on the digital signal processor TMS320F2812, where the mathematical models of the diesel generator and the control of the inverter are computed in real-time. Parameters for the model were obtained from commercially available components. Experimental results for different values of speed droop showed that the emulator achieves a satisfactory performance in the transient and stationary response. For the stationary response, the measured frequency deviates from theoretical values with a mean absolute error of: 0.06 Hz for 0% droop, 0.037 Hz for 3% droop, and 0.087 Hz for 5% droop. For the transient response, the measured frequency nadir deviates from simulations in: 0.05 Hz for 0% droop, 0.02 Hz for 3% droop, and 0.1 Hz for 5% droop.

关键词： Diesel Generator emulator Inverter Frequency Control Mini-Grid

Development of an emulator for the Plasma Process Control

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Journal of Mechanics Engineering and Automation 2015年第1期5卷 10-18页

作者： Marie-Pierre Planche Taikai Liu Sihao Deng Ghislain Montavon Research Institute on Transport Energy and Society--Laboratory of Engineering Research on Materials Processes and SurfacesUniversity of Technology of Belfort-Montbeliard Belfort 90010 France

This work aims at developing an automatic system for the control of the APS （air plasma spraying） plasma process in which some instability phenomena are present. APS is a versatile technique to produce coatings of powder material at high deposition rates. Using this technique, powder particles are injected into a plasma jet, where they are melted and accelerated towards a substrate. The coating microstructures and properties depend strongly on the characteristics of the plasma jet, which can be controlled by the adjustment of the process parameters. However, the imeractions among the spray variables, render optimization and control of this process are quite complex. Understanding relationships between coating properties and process parameters is mandatory to optimize the process technique and the product quality. We are interested in this work to build an on-line control model for the APS process based on the elements of artificial intelligence and to build an emulator that replicates the dynamic behavior of the process as closely as possible.

关键词： Atmospheric plasma spray process parameters artificial neural networks fuzzy logic emulator

GNSSEM2: A Software Defined Radio emulator for Space borne GPS+BD2 Receivers

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GNSSEM2: A Software Defined Radio Emulator for Space borne G...

Model and control emulator of Giant magnetostriction actuator

第四届中国卫星导航学术年会

作者： Chen Xi Gao Wenyun Zhang Zhonghua Space Center Tsinghua University

A SDR-based radio frequency GNSS emulator named GNSSEM2 （GNSS emulator 2） is proposed, which is designed to support the emulation and RF signal replay for space borne GPS and Beidou-2 （BD2） receivers for space vehicles in LEO, MEO, GEO and Lunar return orbits. The GNSSEM2 is essentially a computer software armed with an USB extension hardware. Its computer software can generate precisely combined 4MHz IF signal samples of all GPS/BD2 satellites in view at the emulated GNSS receiver. The USB extension hardware of the GNSSEM2 is based on the most recent SDHC Card mass storage technology, which can store and playback IF samples, up-convert to GPS and BD2 RF output for hours. In this paper, key aspects of GNSSEM2 are presented in details. For evaluations, the output of the GNSSEM2 was fed into a space-borne GPS L1 receiver. The positioning results showed that GNSSEM2 performed well, which made it a powerful tool for the development of the space borne GPS+BD2 receivers.

关键词： Software defined radio GPS BeiDou-2 emulator

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Model and control emulator of Giant magnetostriction actuato...

Paragon CD－ROM emulator

2010 Chinese Control and Decision Conference

作者： Jianmin Xi~1,Zhongbo He,Dongwei Li,Haitao Zhao 1.Department 1~(st) Mechanical Engineering College,Shijiazhuang 050003

＜正＞There is a static state characteristic experimental study on the magnetostriction *** the experimental,the ideal working section was *** this element,the mathematic model and the PID control emulator was *** the PID control emulator,the article get the result of emulator and modification *** that the GMA model and PID control model is availability.

关键词： Giant magnetostrictive actuator static state characteristic emulator

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软件世界（PC任我行） 2002年第11期 29-29页

作者：张然

Laser-RF synchronization based on digital phase detector

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Nuclear Science and Techniques 2017年第4期28卷 97-102页

作者： Jin Yang Ying-Chao Du Li-Xin Yan Gang Huang Qiang Du Yi-Lun Xu Wen-Hui Huang Huai-Bi Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084 China Key Laboratory of Particle and Radiation Imaging (Tsinghua University) Ministry of Education Beijing 100084 China Lawrence Berkeley National Laboratory BerkeleyCA 94720 USA

Laser oscillator synchronization with RF reference signal is ultra-important for a modern light source based on the *** Tsinghua Thomson scattering X-ray source,we have synchronized the mode-locked laser oscillator to RF reference signal with 48.2 fs RMS relative *** fundamental and harmonic signals derived from photo diode detection are used for laser-RF synchronization in our *** fundamental signal is for coarse laser-RF synchronization and multiple laser oscillator *** harmonic signal is for high precise phase *** digital phase detector is implemented in the synchronization scheme for less noise,replacing the mixing to DC phase detection *** digital processing algorithm for synchronization is commonly used in low-level RF control *** order to test the phase locking loop logic without damaging the real laser oscillator,a laser oscillator emulator was developed for phase *** paper will report the laser-RF synchronization scheme and its *** laser oscillator emulator system will also be introduced here.

关键词： Laser oscillator Synchronization RF LLRF emulator

A data quality monitoring software framework for the BESⅢ experiment

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Chinese Physics C 2012年第1期36卷 62-66页

作者： HU Ji-Feng ZHENG Yang-Heng SUN Xiao-Dong JI Xiao-Bin Graduate University of Chinese Academy of Sciences Beijing 100049China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Data quality monitoring （DQM） plays an important role in data taking at the BESⅢ *** is used to monitor detector status and data quality.A DQM framework （DQMF） has been developed to make it possible to reuse the BESⅢ offline reconstruction system in the online *** this framework,the DQMF can also simulate a virtual data taking environment,transfer events to the event display,publish histograms to a histogram presenter in a fixed interval,and dump histograms into a ROOT *** DQMF has been stably running throughout BESⅢ data taking.

关键词： BESⅢ DQM BOSS emulator

An Improved Treed Gaussian Process

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Applied Mathematics 2020年第7期11卷 613-638页

作者： John Guenther Herbert K. H Lee Department of Statistics and Biostatistics California State University Hayward CA USA Department of Statistics University of California Santa Cruz CA USA

Many black box functions and datasets have regions of different variability. Models such as the Gaussian process may fall short in giving the best representation of these complex functions. One successful approach for modeling this type of nonstationarity is the Treed Gaussian process [1], which extended the Gaussian process by dividing the input space into different regions using a binary tree algorithm. Each region became its own Gaussian process. This iterative inference process formed many different trees and thus, many different Gaussian processes. In the end these were combined to get a posterior predictive distribution at each point. The idea was that when the iterations were combined, smoothing would take place for the surface of the predicted points near tree boundaries. We introduce the Improved Treed Gaussian process, which divides the input space into a single main binary tree where the different tree regions have different variability. The parameters for the Gaussian process for each tree region are then determined. These parameters are then smoothed at the region boundaries. This smoothing leads to a set of parameters for each point in the input space that specify the covariance matrix used to predict the point. The advantage is that the prediction and actual errors are estimated better since the standard deviation and range parameters of each point are related to the variation of the region it is in. Further, smoothing between regions is better since each point prediction uses its parameters over the whole input space. Examples are given in this paper which show these advantages for lower-dimensional problems.

关键词： Bayesian Statistics Treed Gaussian Process Gaussian Process emulator Binary Tree

Finding and Choosing among Multiple Optima

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Applied Mathematics 2014年第2期5卷 300-317页

作者： John Guenther Herbert K. H. Lee Genetha A. Gray Department of Applied Mathematics and Statistics University of California Santa Cruz USA Quantitative Modeling and Analysis Sandia National Laboratories Livermore USA

Black box functions, such as computer experiments, often have multiple optima over the input space of the objective function. While traditional optimization routines focus on finding a single best optimum, we sometimes want to consider the relative merits of multiple optima. First we need a search algorithm that can identify multiple local optima. Then we consider that blindly choosing the global optimum may not always be best. In some cases, the global optimum may not be robust to small deviations in the inputs, which could lead to output values far from the optimum. In those cases, it would be better to choose a slightly less extreme optimum that allows for input deviation with small change in the output;such an optimum would be considered more robust. We use a Bayesian decision theoretic approach to develop a utility function for selecting among multiple optima.

关键词： Bayesian Statistics Treed Gaussian Process emulator Decision Theory Optimization