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Transverse flux permanent magnet machine (TFPMM) has advantages of arbitrarily set poles and adjustable cross-section of armature winding, which is suitable for the traction motor geared to urban rail transit industry. This paper analysis and optimizes the shape of the omega-hoop stator of the proposed TFPMM. The original and optimized models are described by three-dimensional (3-D) finite element analysis (FEA). The electromagnetic characteristics of both structures are evaluated and analyzed. The results indicate that the reduction of stator hoop brings about shorter magnetic circuit to achieve better magnetic field and compact volume performances.

Praseodymium-doped indium zinc oxide (PrIZO) channel materials have been fabricated by a solution process with conventional chemical precursor. The PrIZO-based thin-film transistors (TFTs) exhibited a field-effect mobility of 10.10 cm2/V s, a subthreshold swing value of 0.25 V/decade, and an Ion/ Ioff ratio of 108. The as-fabricated PrIZO-TFTs showed an improved device performance against positive bias temperature stress (PBTS shift of 1.97 V for 7200 s), which was evidently better than the undoped IZO-TFTs (PBTS shift of 9.52 V). This result indicates that the organic residual (-OCH3 and -CH2-) in metal-oxide semiconductor, which is confirmed to be a dominant effect on the performance of PBTS, can be passivated by the rare earth of praseodymium element. The residual is intended to be oxidized with a more stable ester group with the assistant of PrOx, weakening the electron-withdrawing characteristic during the thermal bias stress.

In this research, a passivated methodology was proposed for achieving good electrical characteristics for back-channel-etch (BCE) typed amorphous Si-Sn-O thin film transistors (a-STO TFTs). This methodology implied that the thermal annealing (i.e., pre-annealing) should be carried out before deposition of a SiOx passivation layer. The pre-annealing played an important role in affecting device performance, which did get rid of the contamination of the lithography process. Simultaneously, the acceptor-like sub-gap density of states (DOS) of devices was extracted for further understanding the reason for improving device performance. It found that the SiOx layer could reduce DOS of the device and successfully protect the device from surroundings. Finally, a-STO TFT applied with this passivated methodology could possess good electrical properties including a saturation mobility of 4.2 &plusmn, 0.2 cm2/V s, a low threshold voltage of 0.00 V, a large on/off current ratio of 6.94 &times, 108, and a steep subthreshold swing of 0.23 V/decade. The threshold voltage slightly shifted under bias stresses and recovered itself to its initial state without any annealing procedure, which was attributed to the charge trapping in the bulk dielectric layers or interface. The results of this study indicate that a-STO TFT could be a robust candidate for realizing a large-size and high-resolution display.

The thin-film transistor (TFT) driving circuit is a separate electronic component embedded within the panel itself to switch the current for each pixel in active-matrix organic light-emitting diode displays. We reported a TFT-directed dye electroplating method to fabricate pixels; this would be a new method to deposit films on prepatterned electrode for organic full-color display, where TFT driving circuit provide a switching current signal to drive and direct dye depositing on selected RGB pixels. A prototype patterned color pixel matrix was achieved, as high-quality light-emitting films with uniform morphology, pure RGB chromaticity, and stable output.

Ultra-high definition displays have become a trend for the current flat plane displays. In this study, the contact properties of amorphous silicon–tin oxide thin-film transistors (a-STO TFTs) employed with source/drain (S/D) electrodes were analyzed. Ohmic contact with a good device performance was achieved when a-STO was matched with indium-tin-oxide (ITO) or Mo electrodes. The acceptor-like densities of trap states (DOS) of a-STO TFTs were further investigated by using low-frequency capacitance–voltage (C–V) characteristics to understand the impact of the electrode on the device performance. The reason of the distinct electrical performances of the devices with ITO and Mo contacts was attributed to different DOS caused by the generation of local defect states near the electrodes, which distorted the electric field distribution and formed an electrical potential barrier hindering the flow of electrons. It is of significant importance for circuit designers to design reliable integrated circuits with SnO2-based devices applied in flat panel displays.

The issue of high dust concentration and the difficulty of head-on collection were investigated in this study. The theory of gas-solid two-phase flow was used to conduct numerical simulations on the air flow and dust concentration of the inside intake and the outside pressing particle collector using the FLUENT 6.3.26 software. The best optimization scheme was obtained by analyzing the simulation results of the air flow and dust concentration. Results indicated that when the diameter of the external cavity was 700 or 900 mm, the working surface of the working environment was not effectively improved. In comparison, when the diameter of the external cavity was optimized to 800 mm, most of the dust was trapped in the working face, and the working environment was significantly improved.

For MIMO nonlinear differential-algebraic equations (DAE) subsystem, the Backstepping stabilization control method is studied and the results are applied to the decentralized control of power system. The concept of vector relative order for MIMO nonlinear DAE subsystem is put forward. If the vector relative order exists, then the subsystem can be transformed equivalently by a diffeomorphism and a feedback. Next the Backstepping method is used to design the stabilization controller, through which the asymptotic stability of the whole closed-loop system is obtained. Finally the synchronous generator excitation and valve control is studied, and the simulation results illustrate the utility of the method proposed in this paper.

This paper proposes a physics-based model of flat-band capacitance Cfb for metal oxide thin-film transistors, in which the influences of free carriers and electrons trapped in deep/tail states are taken into account. Hereinto, a parameter Ls is introduced to characterize the screening length in the metal oxide semiconductor, which is similar to the extrinsic Debye length (Ld) for conventional MOS structure. Based on the proposed model, the flat-band voltage Vfb can be consequently determined as the gate voltage corresponding to Cgs equal to Cfb. It is shown that the value of Vfb determined by the proposed model is consistent with that extracted from experimental data of I-V and C-V or the simulated results of 2D device simulator ATLAS. Moreover, we investigate the effect of the parameters of density of states on the flat band capacitance and Cgs-Vgs characteristics of metal oxide TFTs by ATLAS in details. It is found that both tail states and deep states should be simultaneously taken into account for determining the flat band capacitance and flat band voltage of metal oxide TFTs. The proposed model for the flat band capacitance of metal oxide TFTs is expected to be useful for device characterization since it is analytical and physically meaningful.

Transverse flux permanent magnet generator (TFPMG) with double-C stator-hoop and flux-concentrated rotor attracts people's attention due to its high power density and simple fabricated procedure. The structure and electromagnetic characteristics of the proposed generator with different pole-pair numbers are described and analyzed in detail by three-dimensional (3-D) finite element method (FEM). The principle and feasibility of the proposed generator are evaluated and confirmed. Based on the analysis, the 12 pole-pair model is recognized as the better generator, which provides lower cogging torque and higher power density.

A novel transverse flux permanent magnet generator (TFPMG) with staggered stator-hoop and surface-mounted rotor-disk was proposed to achieving the demand of low speed and larger torque capability of the wind power generation. The three-dimensional (3D) finite element analysis (FEA) is employed to compute the electromagnetic characteristics of flux density, EMF, winding inductance, and cogging torque of the generator. The theoretical feasibility and operation principles of the designed scheme are also analysed and described. The FEM results show that the power density of the generator can be significantly increased due to the structure of staggered stator-hoop and surface-mounted rotor-disk. A generator prototype is manufactured and experiments are conducted to validate the effectiveness of the 3D-FEA studies. The experimental results are in good agreement with the analysis preview.

A method of reconstructing the nanosecond signal is carried out based on Labview. A standard nanosecond pulse is got from pulse generator, and then the pulse is measured with a voltage divider. Through model identification, the math expression of the dividere can be get. The best order of the filter is got simultaneously. The study of reconstructing input signal of measurement system is carried out. The result shows that the measurement system can be compensated well based on the math model, and it achieves the prospective objective.

We propose a new type of phase only CGH (Computer Generated Hologram) for on-axis image reconstruction. A theoretical analysis of this CGH is given and some experimental results are reported. By this technique, large space bandwidth product (SBW) and high diffraction efficiency of such CGHs could be obtained.

A real-time adaptive resource allocation algorithm considering the end user's Quality of Experience (QoE) in the context of video streaming service is presented in this work. An objective no-reference quality metric, namely Pause Intensity (PI), is used to control the priority of resource allocation to users during the scheduling process. An online adjustment has been introduced to adaptively set the scheduler's parameter and maintain a desired trade-off between fairness and efficiency. The correlation between the data rates (i.e. video code rates) demanded by users and the data rates allocated by the scheduler is taken into account as well. The final allocated rates are determined based on the channel status, the distribution of PI values among users, and the scheduling policy adopted. Furthermore, since the user's capability varies as the environment conditions change, the rate adaptation mechanism for video streaming is considered and its interaction with the scheduling process under the same PI metric is studied. The feasibility of implementing this algorithm is examined and the result is compared with the most commonly existing scheduling methods.