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The DC circuit breaker technology is one of the key technologies to build multi-terminal DC transmission network. Active DC vacuum circuit breaker (DCVCB) has become the research object. Based on the continuous transition model(CTM) and variable-step 4th-order Runge-Kutta method, sheath development stage during the post-arc dielectric recovery has been simulated and analyzed. Then the influence of...
For the vacuum arc, the parameters of the interelectrode plasma have influences on the electrode process. It is necessary to obtain the parameters and characteristics of the plasma by simulating the plasma among the electrodes. In this paper, based on the analysis of the existing vacuum arc model, combined with the characteristics of vacuum arc fault under different interrupting conditions, the effects...
With the R&D of high voltage direct current (HVDC) transmission, HVDC circuit breaker as the protection equipment has been widely applied in the power system. In this paper, the HVDC vacuum circuit breaker (VCB) based on artificial zero mode has been analyzed, and the genetic algorithm (GA) has been used to optimize the parameters of DC VCB. Moreover, an optimization design method of converting...
A FEM platform is developed to support high precision electric field computing and data analysis. For the precise computing of 550kV SF6 arc quenching chamber, a solve regions division project is presented to improve meshes quality and computation efficiency. At the same time, approach regular triangle algorithm is realized by combing the uniform and gradient disperse for boundary, constraint condition...
A wideband circularly polarized (CP) antipodal curvedly tapered slot antenna (ACTSA) based on waveguide is presented in this paper. By employing the ridge on the broadwall of the slotted waveguide, the antenna can obtain compact structure. The proposed antenna can achieve a bandwidth of 20.8% (56 GHz–69 GHz) for both axial ratio (AR) < 3 dB and reflection coefficient S(1,1) < −10 dB and a gain...
Recently, Convolutional Neural Network (CNN) based models have achieved great success in Single Image Super-Resolution (SISR). Owing to the strength of deep networks, these CNN models learn an effective nonlinear mapping from the low-resolution input image to the high-resolution target image, at the cost of requiring enormous parameters. This paper proposes a very deep CNN model (up to 52 convolutional...
Affordable sensors lead to an increasing interest in acquiring and modeling data with multiple modalities. Learning from multiple modalities has shown to significantly improve performance in object recognition. However, in practice it is common that the sensing equipment experiences unforeseeable malfunction or configuration issues, leading to corrupted data with missing modalities. Most existing...
The large pose discrepancy between two face images is one of the key challenges in face recognition. Conventional approaches for pose-invariant face recognition either perform face frontalization on, or learn a pose-invariant representation from, a non-frontal face image. We argue that it is more desirable to perform both tasks jointly to allow them to leverage each other. To this end, this paper...
This paper addresses the problem of spatio-temporal alignment of multiple video sequences. We identify and tackle a novel scenario of this problem referred to as Nonoverlapping Sequences (NOS). NOS are captured by multiple freely panning handheld cameras whose field of views (FOV) might have no direct spatial overlap. With the popularity of mobile sensors, NOS rise when multiple cooperative users...
In this paper, we provide an overview of the progress on producing accurate and consistent ocean color products from the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard the Suomi National Polar-orbiting Partnership (SNPP). To meet requirements from broad users (e.g., operational, research, modeling, etc.), we have proposed and now been routinely producing two VIIRS ocean color data streams,...
Massive open online courses and other forms of remote education continue to increase in popularity and reach. The ability to efficiently proctor remote online examinations is an important limiting factor to the scalability of this next stage in education. Presently, human proctoring is the most common approach of evaluation, by either requiring the test taker to visit an examination center, or by...
Urban freeway is the aorta of urban traffic, but in recent years, traffic congestion has become prominent increasingly, which seriously affects the urban traffic efficiency. Based on the analysis of the traffic flow characteristic of urban freeway and streets system, the macroscopic traffic flow model integrated urban freeway with streets system is established, by using store-and-forward model to...
In micromanipulation, lots of methods have been developed to manipulate objects in microscale. However, few of them can be applied in both the transportation and the rotation of the micro objects. In this paper, we present a novel method to realize the non-contact transportation and rotation of the micro objects based on the vibration-induced swirl flow. A piezo actuator is set between the glass needle...
Helical structure assembled by hydrogel microfibers is significant for culture of smooth muscle cells. However, the helical structure is only fabricated at the macroscale, while the fabrication of helical microstructure is still a challenge due to the lack of assembly method. In this paper, we propose a robotics-based assembly method to handle such challenge. An electromagnetic needle (EMN) is employed...
A dual-polarized wideband substrate-integrated-waveguide fed aperture-coupled slot antenna array for 60 GHz is proposed. By cutting a semicircle shape on the edge of the crossed-slot antenna, the impedance bandwidth of the proposed antenna is effectively widen and achieves overlapped bandwidth of 16.7% for simulated |S11| and |S22|. In addition, over 35 dB isolation between two polarization and low...
RNN-based approaches have achieved outstanding performance on action recognition with skeleton inputs. Currently these methods limit their inputs to coordinates of joints and improve the accuracy mainly by extending RNN models to spatial domains in various ways. While such models explore relations between different parts directly from joint coordinates, we provide a simple universal spatial modeling...
Security problems have become obstacles in the practical application of wireless sensor networks (WSNs), and intrusion detection is the second line of defense. In this paper, an intrusion detection based on dynamic state context and hierarchical trust in WSNs is proposed, which is flexible and suitable for constantly changing WSNs characterized by changes in the perceptual environment, transitions...
Micromanipulation provides researchers a new way to fabricate complex structures through assembling small components, and it is also a useful tool for single cell manipulation. Many micromanipulation methods have been proposed, but only the few are capable of rotation of the micro targets. In this paper, we present a simple non-contact high-speed rotation method based on the local flow generated by...
In micromanipulation, a few of methods can be applied in the rotation of micro objects, which is very important for single cell injection, observation of micro objects and assembly of complex structures. In this paper, we present a novel method to realize the non-contact rotation of the micro objects by the swirl flow which is generated through vibrating glass needle in the fluid. Experiments of rotating...
In the field of image processing, compared with noisy image, high-quality or clean image usually has a positive impact on the final results, which lead to the emergence of image denoising. Recently, the patch-based methods have attracted considerable interest of researchers, which leverage the self-similarity of the noisy image or information of other relevant images. In this paper, we proposed a...
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