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A general equivalent model is proposed to understand theory of characteristic modes for homogenous dielectric and magnetic objects. It provides a convenient way to build up physical relationship between characteristic mode and its complex power supplied.
People are increasingly dependent on intelligent electronic products. However, the vast majority of these intelligent electronic devices are highly dependent on external power supply. If there is no continuous power supply to the equipment for some unknown reasons, the equipment will not be able to work properly, or even will bring us some serious unpredictable consequences, which poses a new challenge...
The operational characteristics of the off-grid microgrid are the basis for studying the operation mechanism and control strategy of microgrid. In this paper, the maximum power point tracking (MPPT) algorithm based on power duty cycle quadratic differential is adopted for the photovoltaic cells. based on the model of photovoltaic cells and lead-acid batteries, At the same time, two kinds of grid control...
This paper presents a novel approach to compute sparse optical flow field, which is different from the traditional feature matching methods such as SURF. The approach consists mainly of three novel parts. First, the improved PatchMatch that is tailored to sparse optical flow computation is used to generate NNF quickly. And the NNF is smoothed using a threshold filtering rather than global optimization...
With the advance of various location-acquisition technologies, a myriad of GPS trajectories can be collected every day. However, the raw coordinate data captured by sensors often cannot reflect real positions due to many physical constraints and some rules of law. How to accurately match GPS trajectories to roads on a digital map is an important issue. Many existing methods still cannot meet stringent...
Locality sensitive hashing (LSH) and its variants are widely used for approximate kNN (k nearest neighbor) search in high-dimensional space. The success of these techniques largely depends on the ability of preserving kNN information. Unfortunately, LSH only provides a high probability that nearby points in the original space are projected into nearby region in a new space. This potentially makes...
Combining with software-defined networking and virtualization technology, Network Function virtualization (NFV) has been proposed as an important technology for constructing scalable network. VNF (Virtual Network Function) redeployment is a critical step for dealing with network evolve. Due to the inner state consistency constraints, VNF migration to a new location is major challenge for redeployment...
Anomaly detection in healthcare data like patient records is no trivial task. The anomalies in these datasets are often caused by mismatches between different types of feature, e.g., medications that do not match with the diagnoses. Existing anomaly detection methods do not perform well when detecting "mismatches" between multiple types of feature, especially when the feature space is high-dimensional...
In this paper, we propose a Robust Discriminant Analysis based on maximum entropy (MaxEnt) criterion (MaxEnt-RDA), which is derived from a nonparametric estimate of Renyi’s quadratic entropy. MaxEnt-RDA uses entropy as both objective and constraints; thus the structural information of classes is preserved while information loss is minimized. It is a natural extension of LDA from Gaussian assumption...
As fossil fuels become less and less, renewable power generations such as wind and solar energy have been regarded as a current trend. However, their intermittent nature and instable output will greatly influence the stability of power system. In order to verify wind-solar hybrid generation system can greatly improve the stability of the micro grid. The study presents and analyzes the output models...
This paper reports our efforts in the development of a fast hybrid high frequency method through addressing four crucial aspects: (i) how to hybridize the physical optics, physical theory of diffraction, and shooting and bouncing rays (pO-PTD-SBR); (ii) how to extend the PO-PTD-SBR to handle objects with thin layer coatings; (iii) how to speed up the PO-PTD-SBR by using the state-of-the-art hardware...
Image classification is a general visual analysis task based on the image content coded by its representation. In this research, we proposed an image representation method that is based on the perceptual shape features and their spatial distributions. A natural language processing concept, N-gram, is adopted to generate a set of perceptual shape visual words for encoding image features. By combining...
This work is a further study on the Generalized Constraint Neural Network (GCNN) model [1], [2]. Two challenges are encountered in the study, that is, to embed any type of prior information and to select its imposing schemes. The work focuses on the second challenge and studies a new constraint imposing scheme for equality constraints. A new method called locally imposing function (LIF) is proposed...
In this paper, we propose to deal with the problems of logistic regression with outliers and class imbalance, which are common in a wide range of practical applications. The robust bounded logistic regression with different error costs is developed to reduce the combined influence of outliers and class imbalance. First, inspired by the Correntropy induced loss function, we develop the bounded logistic...
In order to improve the flexible vibration resulting from solar array, the permanent magnet synchronous motor (PMSM) is used as the drive sources. On the basis of it, a composite control method for solar array drive assembly (SADA) system is proposed in this paper. The combination of a lead-lag network and an adaptive fuzzy controller is applied in the proposed method. The lead-lag network is used...
The performance of stepper motor is closely related to the driving method. Stepper motor subdivision drive is used to transform Servo system of CA6140 lathe. With this method, it can reduce the motor step angle, thereby decreasing machine pulse equivalent to improve the precision of servo control and precision machining.
A photovoltaic controller is a converter which can transform the energy generated by photovoltaic cells and control the battery charging and discharging. The maximum power point tracking (MPPT) technology can maximize the efficiency of photovoltaic cell and effectively improve the efficiency of photovoltaic power generation system. The single-phase buck circuit is often used in a MPPT controller,...
To solve the problem of electromagnetic protection of electronic system in complex electromagnetic environment where it is difficult to do with the traditional technology. We put forward the viewpoints to take an external electromagnetic signal as a noise by comparing the response characteristics of noise between cell and electronic system. Furthermore, it indicates that the role and function of noise...
Unsupervised ranking faces one critical challenge in evaluation applications, that is, no ground truth is available. While PageRank and its variants show a good solution in related objects, they are applicable only for ranking from link-structure data. In this work, we focus on unsupervised ranking from multi-attribute data which is also common in evaluation tasks. To overcome the challenge, we propose...
This paper presents a preliminary study on the nonlinear approximation capability of feedforward neural networks (FNNs) via a geometric approach. Three simplest FNNs with at most four free parameters are defined and investigated. By approximations on one-dimensional functions, we observe that the Chebyshev-polynomials, Gaussian, and sigmoidal FNNs are ranked in order of providing more varieties of...
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