Z-source matrix rectifier

This paper presents a novel Z-source matrix rectifier(ZSMR). To overcome the inherent disadvantage that the voltage transfer ratio for traditional matrix rectifier cannot be more than 0.866, a Z-source network has been combined with the matrix rectifier. The proposed rectifier realizes a voltage-boost function and the Z-source network also serves as power storage and guarantees double filtration grade at the output of the rectifier. The open-circuit zero state is required to obtain the voltage-boost function and ensure the output angle of the current vector to be invariant to obtain the expected power factor. In addition, to widely extend the voltage transfer ratio of the proposed rectifier, this paper presents the switched-inductor matrix rectifier(SL-ZSMR) and tapped-inductor matrix rectifier(TL-ZSMR). The corresponding circuit topologies, control strategies and operating principles are introduced. Both simulation and experiment results are shown to verify the theoretical analysis

High Step-Up Dual-Switch X-Source DC-DC Converters Integrating Various Capacitor-Winding-Diode Voltage-Double Technology

In this article, a new class of high step-up dual-switch X-source dc–dc converters integrating various capacitor-winding-diode voltage-double technology is presented, which are parallel-winding dual-switch X-source dc–dc converters, series-winding dual-switch X-source dc–dc converters, and flipped parallel-winding dual-switch X-source dc–dc converters. According to different winding homonymous end connections, voltage gains and turn ratios of proposed converters have two relations: inversely proportional relations and positive proportional relations. Also, all proposed topologies can produce the higher voltage gain, and own the lower voltage stresses. Operation principles, math derivations, and performance advantages of the proposed converters are analyzed in detail. Finally, the experimental prototype is built to demonstrate the operational feasibility of the proposed converter

An Improved Coupled-Inductor Impedance Source Network With More Freedom in Winding Match

In this paper, an improved coupled-inductor impedance source network (CL-ISN) with more freedom in winding match is proposed. Through introducing three-winding coupled-inductor cells, the proposed CL-ISN can produce the same voltage gain by using different turn ratios among three windings, which will largely increase the freedom in winding match. Also, the proposed CL-ISN can produce the higher boost ability, realize the continuous input current and suppress the start-up inrush current. The topology derivations, math calculations and parameter design of proposed CL-ISN are given out. The proposed CL-ISN is applied for DC-AC converter, and a full comparison between proposed CL-ISN and other impedance source networks are made based on DC-AC converter. Finally, the experiment prototype is built to verify the validity of the theoretical analysis

Consecutive Insulator-Metal-Insulator Phase Transitions of Vanadium Dioxide by Hydrogen Doping

We report modulation of a reversible phase transition in VO2 films by hydrogen doping. A metallic phase and a new insulating phase are successively observed at room temperature as the doping concentration increases. It is suggested that the polarized charges from doped hydrogens play an important role. These charges gradually occupy V3d-O2p hybridized orbitals and consequently modulate the filling of the VO2 crystal conduction band-edge states, which eventually evolve into new valence band-edge states. This demonstrates the exceptional sensitivity of VO2 electronic properties to electron concentration and orbital occupancy, providing key information for the phase transition mechanism.Comment: 16 pages, 4 figure

Application of Weighted Gene Co-expression Network Analysis for Data from Paired Design

Investigating how genes jointly affect complex human diseases is important, yet challenging. The network approach (e.g., weighted gene co-expression network analysis (WGCNA)) is a powerful tool. However, genomic data usually contain substantial batch effects, which could mask true genomic signals. Paired design is a powerful tool that can reduce batch effects. However, it is currently unclear how to appropriately apply WGCNA to genomic data from paired design. In this paper, we modified the current WGCNA pipeline to analyse high-throughput genomic data from paired design. We illustrated the modified WGCNA pipeline by analysing the miRNA dataset provided by Shiah et al. (2014), which contains forty oral squamous cell carcinoma (OSCC) specimens and their matched non-tumourous epithelial counterparts. OSCC is the sixth most common cancer worldwide. The modified WGCNA pipeline identified two sets of novel miRNAs associated with OSCC, in addition to the existing miRNAs reported by Shiah et al. (2014). Thus, this work will be of great interest to readers of various scientific disciplines, in particular, genetic and genomic scientists as well as medical scientists working on cancer

Ultra-Sensitivity Glucose Sensor Based on Field Emitters

A new glucose sensor based on field emitter of ZnO nanorod arrays (ZNA) was fabricated. This new type of ZNA field emitter-based sensor shows high sensitivity with experimental limit of detection of 1 nM glucose solution and a detection range from 1 nM to 50 μM in air at room temperature, which is lower than that of glucose sensors based on surface plasmon resonance spectroscopy, fluorescence signal transmission, and electrochemical signal transduction. The new glucose sensor provides a key technique for promising consuming application in biological system for detecting low levels of glucose on single cells or bacterial cultures