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Clock synchronization is becoming an increasingly important characteristic of modern wide area monitoring and control systems such as the power grid. It provides an opportunity to coordinate control actions and measurement instants across hundreds of miles and numerous network topologies. Devices and networks have advanced to a point where synchronization across a wide area can be achieved within...
This paper presents a novel approach to hierarchical shape classification. We combine two shape features: contour and skeleton. Weights of two features are learned through large-margin optimization. The proposed approach uses a shape tree to efficiently represent the similarity of different shape classes. The tree is generated offline by a bottom-up clustering approach using stochastic optimization...
Practical implementations in distributed model based control face a fundamental trade-off between model complexity and the number of modeled nodes. For linear systems, higher order models better capture the behavior of the system at higher frequencies, but the effective operating frequency range is limited during implementation due to sensor/actuator bandwidth limits, control algorithm limits and,...
Wide-area monitoring (WAM) applications for power distribution rely on accurate global time synchronization. Furthermore, there is interest in replacing current time synchronization methods such as Inter Range Instrumentation Group (IRIG), with distributed time synchronization protocols that utilize the data communication lines eliminating the need for dedicated timing signals within the substation...
The study of growth model is a basic research in forest growth and yield modeling. Most of growth models were developed using ordinary regression method. It is assumed that the observations were independent and obey Gauss distribution. Those models reflect the average growth across different plots, but neglect the correlation and variance between individuals and plots. However, mixed-effects models...
This paper presents a novel hybrid approach based on clustering technique (CT) and least square support vector machine (LS-SVM) denoted as CT-LS-SVM for classifying two-class EEG signals. The study aims to extract representative features from the original EEG data through the CT method and then to classify two-class EEG signals by the LS-SVM using these features as inputs. In order to test the effectiveness...
Precision DC voltage dividers with ratings up to 1000 kV have been built using the 150 kV resistor module developed at the National Measurement Institute, Australia (NMIA). The structure of the 150 kV resistor module and the measurement techniques for evaluating its performance are described. The method for evaluating voltage ratio errors at voltages up to 1000 kV is discussed. It is shown that a...
An important task for target localization is camera calibration, whose purpose is to estimate the internal and external parameters of cameras. A exact mathematical model was established based on a strict geometric constraint relationship. A fast method of external common tangent was provided to obtain the image coordinates. The other parameters of the camera was computed in a reasonable method to...
In this study, 56 ECa profiles, which inversed by the EM38 linear model with Tikhonov regularization method, were selected as the original datum of 3D variation. The spatial variability of ECa at ten depths was simulated by the SGS method. It was shown that not only the spatial distribution characteristics of the original data, but also the volatility of the distribution was well simulated by the...
The influence of the machine topology and dq-axis cross-coupling on the rotor position estimation error in an extended back-EMF based sensorless brushless AC drive is investigated by both finite element analysis and experimentally on four brushless AC machines having different rotor topologies, viz. interior circumferentially magnetized, interior radially magnetized, surface-mounted, and inset magnets...
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