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The rapidly increasing availability of healthcare data from multiple heterogeneous sources has spearheaded the adoption of data-driven approaches for improved clinical research, decision making, and patient management. The patient healthcare data are usually longitudinal and can be expressed as medical event sequences, where the events include clinical diagnosis, medications, laboratory reports, etc...
Half-bridge (HB) modular multi-level converter (MMC) based bipolar HVDC transmission systems can be employed to transfer bulk power over long distances with high reliability and flexibility. However, this configuration exhibits special fault behaviors that should be taken into account during its design stage. For instance, a single-phase-to-ground fault at the valve-side of the HB-MMCs will lead to...
This paper proposes a novel input-series output-parallel (ISOP) current-fed modular dual-active-bridge (CF-MDAB) dc-dc converter for medium-voltage dc (MVDC) system application. The proposed converter exhibits favorite features of DAB converter such as galvanic isolation, soft-switching condition and small passive components. Compared to ISOP DAB converter, the proposed topology has direct dc current...
An analysis of variation of drain current (dID/dt) of silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) in turn-on and turn-off under different temperatures has been performed in this paper. It is shown that the magnitude of turn-off dID/dt is temperature dependent and decreases with tempertature with a fixed supply voltage, load current and gate resistance. While,...
This paper is focused on studying a 1200V SiC JFETs cascode device released recently. The gate drive circuit design and switching performance are compared with its counterpart, 1200 V SiC MOSFETs. The research finds out the gate drive circuit design of SiC JFETs cascode is similar to that of SiC MOSFETs. In addition, an optimized gate driver is designed to minimize the device switching loss without...
We proposed and demonstrated a novel photonic and digital hybrid flexible satellite payload with resources sharing for multi-channel communication payloads at L, S, Ku and Ka band. The system uses microwave photonic up/down conversion to realize receive different band microwave signals and convert to fixed IF frequency. We further show that the photonic and digital hybrid switching is used compared...
The empirical mode decomposition (EMD) combines with Hilbert Transform is a common method of nonlinear and non-stationary signal time frequency analysis. Signal can be decomposed into different intrinsic mode functions (IMF) through the EMD. Each IMF represents a simple oscillation which provides meaningful instantaneous frequency through Hilbert transform. The mode mixing of IMF is a critical problem...
In this work, we jointly address the problem of text detection and recognition in natural scene images based on convolutional recurrent neural networks. We propose a unified network that simultaneously localizes and recognizes text with a single forward pass, avoiding intermediate processes, such as image cropping, feature re-calculation, word separation, and character grouping. In contrast to existing...
In order to solve performance reduction of space-time adaptive processing caused by interfering targets mixing in clutter training samples, a robust training samples detection method based on prior knowledge and sparse recovery is proposed. Firstly, the object region in unit to be detected is locked. Then the sparse complete base is got by discretizing the whole Angle-Doppler plane. After that, hollow...
In this work, a compact tag antenna based on loop structure is proposed for radio frequency identification (RFID) system. The tag has a small overall size of 55 mm × 41.5 mm × 3 mm, with a single conductor layer for lower cost and easy fabrication. Simulation results show that the antenna has a 3 dB bandwidth of 30 MHz when placed on a 200 mm×200 mm metal plate. The antenna can also be mounted on...
We present our previous work in [17] in a more generic way to construct q-ary Golay complementary sets and near-complementary sets of size N and sequence length M · Nm by using different seed sequences, where m is an arbitrary non-negative integer, M is the length of seed sequences and N is a power of 2. The boolean functions of these sequences will also be derived with our method. To illustrate it,...
Orthogonal frequency division multiplexing (OFDM) uses multiple equal-spaced orthogonal subcarriers to carry transmit sequences which has the advantages of flexible bandwidth configuration and good anti-multipath performance. For high data rates in the wireless fading channel transmission, OFDM is one of the most promising wireless technology. However, peak-to-average power ratio (PAPR) can significantly...
The Power Conversion Module (PCM) plays an important role in a shipboard MVDC system which transforms power from a medium-voltage dc to a low voltage dc bus. In this paper, an isolated modular multilevel dc-dc converter (iM2DC) and a dual active bridge (DAB) converter are designed for a 300 kW PCM converter respectively. The total device rating, passive component size, and conversion efficiency of...
With the accelerating process of urbanization, rural migrant workers flood into the cities. Research projects that aim at resettlement and employment promotion of these workers, social stability, as well as economic development have drawn attention of government and scholars alike. With respect to the matching problems of urban employment of rural migrant workers, grey incidence analysis and two-sided...
Sintered silver has received a great deal of recent attention as a high-temperature die-attach material. A detailed study of the sintered silver for bonding insulated gate bipolar transistor dies is reported. The purpose was to compare the reliability between sintered silver and Sn-3Ag-0.5Cu (SAC305) solder joints. It was found that the sintered silver had a porous and crack-free structure. And compared...
We report the effects of multiple reflow cycles on the reliability of Sn-Sb solders. Reflow soldering technology was used to prepare the Sn-Sb joints after 1 reflow cycle, 2 reflow cycles and 3 reflow cycles. We found that the intermetallic compound layers became thicker and denser with the reflow cycle increased. And the samples here had good bonding quality with only a few voids. After 600 thermal...
With the development of internet and information technology, educational informatization is increasingly focusing on the use of modern technology to provide powerful teaching assistance. Learning resources intelligent recommendation is essential in Smart Education. The paper proposes two aspects of recommendation strategy. First is the basic recommendation strategy, which includes teaching process,...
This paper proposes a design to implement Intelligent Examination subsystem in the Internet Plus environment, which uses structure model combining B/S and C/S, JSP technology and SSH frames. Student examination terminal facilitates automatic acquisition and maintenance of exam candidate's face image for automatic authentication of its identity, automatically obtaining examination papers' information,...
This paper investigates the performance of underwater visible light communications (UVLC) systems employing multiple transmitters and/or multiple receivers to exploit the advantage of spatial diversity. Experimental results are further provided to evaluate the error performance of single input multiple outputs (SIMO), multiple inputs single output (MISO) and multiple inputs multiple outputs (MIMO)...
This paper proposes a kind of orbital angular momentum (OAM) mode supporting fiber based on photonic crystal fiber structure, give a design strategy for designing a family of circular photonic crystal OAM fiber with the good transmission performance features such as good quality OAM modes, enough separation of the effective indices, low confinement loss, flat dispersion, large effective area, and...
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