Significant improvement of OLED efficiency and stability by doping both HTL and ETL with different dopant in heterojunction of polymer/small-molecules

This paper reports that the polymer/organic heterojunction doped light-emitting diodes using a novel poly-TPD as hole transport material and doping both hole transport layer and emitter layer with the highly fluorescent rubrene and DCJTB has been successfully fabricated. The basic structure of the heterostructure is PTPD/Alq3. When hole transport layer and electron transport layer are doped simultaneously with different dopant, the electrol quantum efficiencies are about 3 times greater than that of the undoped device. Compared with undoped device and conventional TPD/Alq3 diode, the stability of the doping device is significantly improved. The process of emission for doped device may include carrier trapping as well as FSrster energy transfer.

Fast and accurate analysis of electromagnetic scattering from targets situated in dielectric half space

Electromagnetic scattering from targets situated in half space is solved by applying fast inhomogeneous plane wave algorithm combined with a tabulation and interpolation method. The integral equation is set up based on derivation of dyadic Green＇s functions in this environment. The coupling is divided into nearby region and well-separated region by grouping. The Green＇s function can be divided into two parts： primary term and reflected term. In the well-separated region, the two terms are both expressed as Sommerfeld integral, which can be accelerated by deforming integral path and taking interpolation and extrapolation. For the nearby region, the direct Sommerfeld integral makes the filling of impedance matrix time-expensive. A tabulation and interpolation method is applied to speed up this process. This infinite integral is pre-computed in sampling region, and a two-dimensional table is then set up. The impedance elements can then be obtained by interpolation. Numerical results demonstrate the accuracy and efficiency of this algorithm.

Spatial correlation properties and phase singularity annihilation of Gaussian Schell-model beams in the focal region

By using the generalized Debye diffraction integral, this paper studies the spatial correlation properties and phase singularity annihilation of apertured Gaussian Schell-model （GSM） beams in the focal region. It is shown that the width of the spectral degree of coherence can be larger, less than or equal to the corresponding width of spectral density, which depends not only on the scalar coherence length of the beams, but also on the truncation parameter. With a gradual increase of the truncation parameter, a pair of phase singularities of the spectral degree of coherence in the focal plane approaches each other, resulting in subwavelength structures. Finally, the annihilation of pairs of phase singularities takes place at a certain value of the truncation parameter. With increasing scalar coherence length, the annihilation occurs at the larger truncation parameter. However, the creation process of phase singularities outside the focal plane is not found for GSM beams.

Development of Millimeter-Wave Radio-over-Fiber Technology

Millimeter-wave radio-over-fiber techno- logy demonstrates the potential for providing wireless broad-band service in the next generation wireless communication system.Optical generation of millimeter-wave signal is one of the most important technologies of millimeter-wave radio-over-fiber system.The virtues and shortcomings of some ways of optical generation of millimeter-wave signal are discussed.Then optical millimeter-wave signal transmission perfor- mance is described.Finally,an overview of the millimeter-wave radio-over-fiber system is given.It is suggested that the millimeter-wave radio-over-fiber technology should be paid more attention,especially for modulators for optical generation of millimeter-wave signal and radio-over-fiber system.

A Design of Penetration Ammunition Fuse System Based on Embedded Technology

The hard target smart fuse of penetration ammunition is developing to be smaller, lighter, smarter and multifunction. After analyzing the characteristics of high-g accelerating signals and the penetration algorithms, this paper provides a solution of penetration ammunition fuse system based on embedded technology. This fuse system realizes acquisition of the high-g accelerating signals and uses the appropriate penetration algorithms to process them. The fuse system can not only make the same type of penetration ammunition to attack different kinds of objects accurately, but also meet the other requirements of the function of penetration ammunition fuse system.

Domain Structure of Iron Thin Films Prepared by Sputtering

Microstructure and magnetic domain structure of thin iron film prepared by sputtering were studied by magnetic force microscopy (MFM). Owing to the high lateral resolution of MFM magnetic structure of a single domain is able to be studied. Two series of iron thin films were grown on microcrystalline glass substrate by DC magnetron sputtering. They were prepared at different Ar pressure and annealing time. The results by magnetic force microscopy show both surface topography of the films and their local magnetic domain structure. It is suggested that the pin effect by single domain wall influence magnetic properties of the iron thin films.

Characterization of Fundamental Logics for the Sub-Threshold Digital Design

Digital circuits operating in the sub-threshold regime consume the least energy. The strict energy constraints are desired in the applications which work at the lowest possible supply voltage. On the other hand, the conventional design flow utilizes the technology library provided by the foundry with a fixed voltage boundary, which causes problems when the supply scales down to the sub-threshold regime. In this paper, we present a design methodology to characterize the existing cell library with Liberty NCX to facilitate the standard design flow. It is demonstrated in 0.13 μm complementary metal-oxide-semiconductor （CMOS） technology with the supply voltage of 300 mV.

CHARACTERISTICS OF MICROSTRIP TRANSMISSION LINES

An efficient hybrid field solution to microstrip transmission lines is presented byusing SLE and SLM modes in spectral domain.It by-passes the lengthy process of formulatingthe determinant equation for the unknown propagation constant.Compared with spectral domainadmittance approach,this method is clear in both physical and mathematical senses and may beapplied to a variety of structures.

Effect of MR Element Slant Angle on Output Voltage of Magnetoresistive Device

Correlation between optimum of MR element slant angle and the ratio of magnetic pole length to magnetoresistance element length on linear magnetic encoder is explored in this paper.Optimum slant angle of MR element is different and increases in proportion to the ratio of magnetic pole length to MR element length by slant multi-phase filtering model.

Novel torque ripple minimization algorithm for direct torque control of induction motor drive

To elucidate the principles of notable torque and flux ripple during the steady state of the conventional direct torque control （DTC） of induction machines, the factors of influence torque variation are examined. A new torque ripple minimization algorithm is proposed. The novel method eradicated the torque ripple by imposing the required stator voltage vector in each control cycle. The M and T axial components of the stator voltage are accomplished by measuring the stator flux error and the expected incremental value of the torque at every sampling time. The maximum angle rotation allowed is obtained. Experimental results showed that the proposed method combined with the space vector pulse width modulation （SVPWM） could be implemented in most existing digital drive controllers, offering high performance in both steady and transient states of the induction drives at full speed range. The result of the present work implies that torque fluctuation could be eliminated by imposing proper stator voltage, and the proposed scheme could not only maintain constant switching frequency for the inverter, but also solve the heating problem and current harmonics in traditional induction motor drives.

Transient Response of Twisted Wire Pairs IIIuminated by HEMP

In this paper,the time domain characters of the response of twisted wire pairs(TWPs) excited by the high-altitude electromagnetic pulse (HEMP) have been proposed.The finite different time domain transmission line model (FDTD-TLM) method,which we have proposed previously,is used to calculate the terminal response of TWP.It shows that the time domain response includes two stages:The transient stage and damped stage.The transient stage is the key point of the coupling and protecting research.The influence factors of the transient stage have been analyzed.In the end,we obtain the changes of the induced voltage when the incident wave parameters and TWP parameters change.

Theoretical study of wave propagation along the coaxial waveguide filled with moving magnetized plasma

This paper presents detailed theoretical study on the theory of wave propagation along the coaxial waveguide filled with moving magnetized plasma （CWMMP）. Making use of the Lorentz transformation and the constitutive transformation, Maxwell＇s equations lead to the coupled non-homogeneous differential equations which govern the wave propagation in CWMMP, and then analytical solutions have been obtained. The discussion about the eigenvalues of the waves and detailed studies on the fields are carried out. It finds that the fields of the CWMMP are composed of two parts with different eigenvalues. Numerical calculations show that because of Doppler shift effect, the eigenvalues of the modes in such a case is quite different from those of the CWMMP. And a detailed discussion on the dispersion characteristic of CWMMP is presented.

Performance of an Adaptive Optics System with Dual Deformable Mirrors

One deformable mirror （DM） in conventional adaptive optics system can not meet the needs of large scale and high order aberration compensation. In this paper, a dual DMs way is presented, which needs the decoupling of dual DMs. In dual DMs adaptive optics （AO） system, the decoupling algorithm of dual DMs is deduced. Stroke of one of DMs is large, spatial frequency of the other is high. According to the algorithm, the large stroke DM （LSDM） corrects low order aberration only, and the high spatial frequency DM （HSFDM） corrects other aberration. The experimental result for two 61-DM AO system is presented. The result indicates that the experimental performance of dual DMs AO system is almost the same with that of the conventional AO system using single DM with ideal stroke and equivalent spatial frequency.

NEURAL MEMORY MODEL AND ITS PIECEWISE-LINEAR NETWORK REALIZATION

This paper studies the neural networks by means of neural functions.The memoryfunction of neural networks is investigated and its mathematical model is given.The model issynthesized by a piecewise-linear resistive network which exhibits many properties of artificialneural network such as parallelism,real-time processing capability,distribution,adaptation.Inaddition,all parameters of the network are expressed analytically by the patterns and featureswhich are memorized in the network.

The effect of anodizing temperature on the structure and electrical properties of Al-Ti composite oxide film

The Al-Ti composite oxide films with high dielectric constant were prepared by hydrolysis precipitation and anodizing. The growth, structure and electrical properties of the Al-Ti composite oxide films formed at different anodizing temperatures from 25℃ to 85℃ have been studied by dissolution of anodic oxide films, Auger electron spectroscopy (AES), and electrical measurements. With the anodizing temperature increasing, the film growth rate increases, the structure of two layers in the Al-Ti composite oxide film converts into three layers, I-V characteristics change evidently, and the specific capacitance achieves a peak value at about 75℃. The local breakdown in the composite oxide films formed at 50℃ occurs obviously, which may be contributed to the lowest leakage current and the highest withstanding voltage.

Design and optimization of linearly graded-doping junction termination extension for 3.3-kV-class IGBTs

A linearly graded-doping junction termination extension （LG-JTE） for 3.3-kV-class insulated gate bipo- lar transistors （IGBTs） was proposed and experimentally investigated. Unlike conventional multi-implantation uti- lizing more than one photolithography step, a single mask with injection window widths varied linearly away fi＇om the main junction to the edge was implemented in this proposed structure. Based on the simulation results, IGBTs with LG4TE structures were successfully fabricated on the domestic process platform. The fabricated devices exhibited a 3.7 kV forward-blocking voltage, which is close to the theoretical value of an ideal parallel plane case. This is the first success in fabrication 3.3-kV-class 1GBT in a domestic application.

Study of propagation characteristics of outdoor-to-indoor channel in the 60-GHz band

The millimeter-wave frequency band(30~300 GHz)has received significant attention.Millimeter-wave frequencies have been used for backhaul,cell communication,and other high speed communication.With the advent of 5G communication,millimeter-wave frequencies such as 60-GHz band have been attracting attention as possible candidate for next-generation wireless networks.The traditional application for 60-GHz band is point-to-point communication.Some typical scenarios have been cited in a recent 5G white paper.There exist some traditional channel models for 3G and 4G communication.However,5G has a new channel model(the outdoor-to indoor channel model,or O2I)that has not been clearly studied.Some conventional channel measurements have been conducted for this new band.Two measurement systems in the 60-GHz band for penetration loss and small-scale measurement for different scenarios are presented.By analyzing our measurement data,we can prove that the O2I channel does not generate new paths and only add some material penetration loss.

A new layered space-time detection algorithm for frequency selective fading multiple-input multiple-output channels based on particle filter

In this paper, a new observation equation of non-Gaussian frequency selective fading Bell Labs layered space time （BLAST） architecture system is proposed, which is used for frequency selective fading channels and non-Gaussian noise in an application environment of BLAST system. With othogonal matrix triangularization （QR decomposition） of the channel matrix, the static observation equation of frequency selective fading BLAST system is transformed into a dynamic state space model, and then the particle filter is used for space-time layered detection. Making the full use of the finite alphabet of the digital modulation communication signal, the optimal proposal distribution can be chosen to produce particle and update the weight. Incorporated with current method of reducing error propagation, a new space-time layered detection algorithm is proposed. Simulation result shows the validity of the proposed algorithm.

High dV/dt immunity MOS controlled thyristor using a double variable lateral doping technique for capacitor discharge applications

An analysis model of the dV/dt capability for a metal-oxide-semiconductor （MOS） controlled thyristor （MCT） is developed. It is shown that, in addition to the P-well resistance reported previously, the existence of the OFF-FET channel resistance in the MCT may degrade the dV/dt capability. Lower P-well and N-well dosages in the MCT are useful in getting a lower threshold voltage of OFF-FET and then a higher dV/dt immunity. However, both dosages are restricted by the requirements for the blocking property and the forward conduction capability. Thus, a double variable lateral doping （DVLD） technique is proposed to realize a high dV/dt immunity without any sacrifice in other properties. The accuracy of the developed model is verified by comparing the obtained results with those from simulations. In addition, this DVLD MCT features mask-saving compared with the conventional MCT fabrication process. The excellent device performance, coupled with the simple fabrication, makes the proposed DVLP MCT a promising candidate for capacitor discharge applications.

Multi-Layer Graph Generative Model Using AutoEncoder for Recommendation Systems

Given the glut of information on the web,it is crucially important to have a system,which will parse the information appropriately and recommend users with relevant information,this class of systems is known as Recommendation Systems(RS)-it is one of the most extensively used systems on the web today.Recently,Deep Learning(DL)models are being used to generate recommendations,as it has shown state-of-the-art(SoTA)results in the field of Speech Recognition and Computer Vision in the last decade.However,the RS is a much harder problem,as the central variable in the recommendation system’s environment is the chaotic nature of the human’s purchasing/consuming behaviors and their interest.These user-item interactions cannot be fully represented in the Euclidean-Space,as it will trivialize the interaction and undermine the implicit interactions patterns.So to preserve the implicit as well as explicit interactions of user and items,we propose a new graph based recommendation framework.The fundamental idea behind this framework is not only to generate the recommendations in the unsupervised fashion but to learn the dynamics of the graph and predict the short and long term interest of the users.In this paper,we propose the first step,a heuristic multi-layer high-dimensional graph which preserves the implicit and explicit interactions between users and items using SoTA Deep Learning models such as AutoEncoders.To generate recommendation from this generated graph a new class of neural network architecture-Graph Neural Network-can be used.