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We show the manipulation of spin flow of light in valley photonic crystals. Due to the coupled valley spin physics, both photonic valley Hall effect and unidirectional spin flow are realized in bulk crystal.
This paper introduces a 97% efficiency medium voltage (MV) Solid State Transformer (SST) based on two-level single stage (TLSS) topology and 15 kV SiC MOSFETs. Series resonant converter (SRC) is implemented as the main stage and is identified as a current source (CS) SRC for the first time. Equivalent resonant frequency of the proposed CS-SRC is analyzed in both time domain and frequency domain. Resonant...
We present variational generative adversarial networks, a general learning framework that combines a variational auto-encoder with a generative adversarial network, for synthesizing images in fine-grained categories, such as faces of a specific person or objects in a category. Our approach models an image as a composition of label and latent attributes in a probabilistic model. By varying the fine-grained...
As in-line interference between geostationary(GEO) and Non-Geostationary(NGEO) systems is becoming more and more serious. We propose an efficient utilisation of the adaptive modulation and coding (AMC) scheme for spectral coexistence of GEO and NGEO satellites to mitigate in-line interference. Results of Simulation show that the proposed scheme can improve the performance of the NGEO system in comparison...
In this paper, a novel Cross-layer Dynamic Bandwidth Allocation Algorithm Based on Convex Optimization Theory(CO-CDBA) in Digital Video Broadcast-Return Channel via Satellite system is proposed. A novel utility function by taking application layer, Data Link Layer and physical layer(PHY) parameters into account is established. The Dynamic Bandwidth Allocation(DBA) problem is converted to a convex...
Radio fuze has attracted much study in ground-based air-defence artillery field. It requires a high-resolution radar to recognize, position, track and control multiple projectiles. For this, we present a cooperative multiple-target tracking (CMTT) mechanism with MIMO radar, where projectiles can actively transmit signal to radar for target identification, localization, and tracking. The signal is...
Respiratory motion estimation plays a significant role in radiation therapy. Previous motion estimation approaches usually depended on 4DCT, which introduced extra radio dose for patients, and the local motion details were ignored in the statistical model. In this paper, we propose a novel estimation framework, which employs the Sparse Motion Field Presentation (SMFP) method to obtain a coarse motion...
This paper presents a Neural Aggregation Network (NAN) for video face recognition. The network takes a face video or face image set of a person with a variable number of face images as its input, and produces a compact, fixed-dimension feature representation for recognition. The whole network is composed of two modules. The feature embedding module is a deep Convolutional Neural Network (CNN) which...
This study aims to improve students' argumentative capability and enable them to produce better argumentative essays. The "digital argument-map writing system" was designed for this study to help students build a complete structure of argumentation step by step so they can produce better argumentative essays with the structure as a thinking frame. We conducted an experiment to the students...
"English Practice" is a mobile learning app that allows learners to test their English grammar usage. In this study, we observed 97,746 users and the results showed there are some factors might have certain influence on taking quiz score such as continent, country, time taking Quiz, and device screen size. First, learners who are from Europe tend to have the highest score. Asian learners...
In traditional teaching, teachers transmit knowledge, and students receive the information passively in the classroom. There are few opportunities as well as proper situations for students to apply the acquired knowledge, in other words, students do not know how to use what they have learned in their daily lives. In this study, we designed a system for learning by authoring scripts, setting stage,...
A Ku Band (15∼18 GHz) 4-Element (4 Transmitters/4 Receivers) fully differential phased array transceiver is designed and fabricated using a 180nm CMOS process. The proposed phased array integrated with T/R switches and SPI controller is based on an all-RF structure. TX and RX channels are placed side-by-side to improve integration density and isolation. Each channel consists of a 5-bit phase shifter...
It is necessary to transmit the image from the ammunition platform to the terrestrial system in real time when the TV guided weapon strikes the ground target. For the large amount of HDTV images, due to the limited bandwidth of signal transmission, real-time transmission can't be realized. As an emerging theory, compressive sensing provides the possibility of real-time transmission of HDTV video signals...
Target recognition is a key technology in guided weapon systems. In this paper, an algorithm of target recognition based on local part is presented for the armored target in complex background. By constructing a variable target model to identify the local part of the target, the latent support vector machine is used to find the position of the part, and the position of the whole target is identified...
This study aims to analyse the current method in diagnosing early Alzheimer disease and offer a new method to improve the performance of bioinformatics techniques. It proposes a hybrid MRI image processing method to improve the image quality for Alzheimer disease classification. This hybrid method has four stages consisting of image pre-processing, segmentation, feature extraction, and classification...
Utilities have deployed tens of millions of smart meters, which record and transmit home energy usage at fine-grained intervals. These deployments are motivating researchers to develop new energy analytics that mine smart meter data to learn insights into home energy usage and behavior. Unfortunately, a significant barrier to evaluating energy analytics is the overhead of instrumenting homes to collect...
We survey network topologies, in particular networks with full all-to-all bandwidth scaling. For more detailed study, we select several recently introduced, promising networks that are cheaper than a 3-level Fat-tree. Through a combination of analysis and simulation on selected supercomputer workloads, we compare these networks according to desirable network properties such as robust performance,...
With the development of wireless communication technology, the research process of RF power amplifier (RFPA) is promoted greatly. This paper presents the design and measurements of a broadband LDMOS RF power amplifier. The power amplifier adopts Source-Pull and Load-Pull to design the input and output matching circuits. And ADS is used to optimize and simulate the circuits. The frequency of the power...
This paper discusses the advancements in the development of the medium voltage solid state transformer (SST) based on 15 kV SiC MOSFET and JBS diode. Designed for 7.2 kV single phase distribution grid applications, the medium voltage SST converts high voltage AC to low voltage 240/120V ac. The use of ultra-high voltage SiC devices allows the simplification of the power conversion circuit topology...
The smooth impact drive mechanism (SIDM) is driven by the asymmetry drive signal and the motions of "stick" and "slip" are produced at the driving part of friction rod. The motions can influent the slider displacement. The motions are helpful to analysis qualitatively and quantitatively the slider displacement including forward, backward and valid step. The SIDM motion process...
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