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We report on blue phosphorescent organic light-emitting diodes (PHOLEDs) with biphenyl (Spiro [fluorene-9,9′-xanthen]-2-yl) phosphine oxide (SFX2PO) host. The device studied in this work has the structure of ITO/m-MTDATA:MoOx3:1(8nm)/m-MTDATA(32nm)/ TAPC(10nm)/SFX2PO: Firpic (10nm)/Bphen (40nm)/LiF(1nm)/Al (200nm). Maximum luminance of 9120 cd/m2 and power efficiency of 16.84 lm/w have been achieved in this device.

The existing safety evaluation of high-speed milling cutter mainly based on ISO15641 standards, which by idling experiments, then analysis and determine centrifugal force conditions what cause permanent deformation and fracture destructive of cutter, this method cannot be forecast and control the dynamic evolution of the milling cutter's safety and reliability, when cutting load changed suddenly.This paper using the high speed milling cutter's failure criteria and safety margin model of cutting hardened steel, analysed and evaluated coupled thermal field distribution caused by hardened steel surface feature that changed frequently and cutter's impact, fatigue, strength, stiffness, safety margin which cuased by mutated shock load of cutter, then forecast safety and reliability of high-speed milling cutter, and proposed the control method of safety and reliability that could milled hardened steel in high speed.

Existing research on machined surface topography, only consider its response to vibration or wear certain factors, both vibration and wear impact on machined surface topography exist ambiguity and uncertainty, it cannot solve the design conflicts of machined surface topography. For this, this paper analyzes blade installation error, tool wear, vibration and deformation to reveal effects of tip space trajectory, build a three-dimensional model of machined surface topography in simulation, extract its characteristic parameters, by simulation of different amplitudes and wear, found that axis amplitude is a key factor affecting surface residual height, flank wear affects contour distribution distance significantly, by specimen milling experiments, use vibration measuring instrument and ultra-depth microscopy to obtain vibration, wear characteristics and machined surface topography parameters under different cutting parameters, then use the gray system theory to get correlation analysis of the test data, results showed that the influence of tool wear on machined surface topography is prominent than tool vibration.

Focus on the problems that heavy duty machine tool lack of fault samples and process information in repetitive assembly, result in the existing assembly process method can’t meet the repetitive assembly accuracy. According to characteristics of local machine assembly process, propose its assembly repeatability evaluation indexes. Establish the mapping relation among machine performance, assembly accuracy and structure, and built a hierarchical model of assembly process, obtain the process optimal design scheme of assembly accuracy repeatability. Use the multivariate function differential method, propose a calculation method of heavy machine assembly accuracy, and verify applicability of the method, depend on the machine loads and structure criterions, propose heavy machine assembly accuracy repeatability optimization method, example analysis shows that: the servo effect of repetitive assembly accuracy in new process is obvious, simultaneously stress field magnitude and stability of new technology is better than the original, realize effective control of the machine tool assembly accuracy repeatability.

A novel apparatus is introduced in this paper used to measure high voltage electric energy based on three-phase four-wire virtual-ground theory. The virtual-ground design, Faraday shielding technique and Warner DC (Direct Current) self-supply method are integrated in this apparatus based on new I/V, V/V techniques to realize high accuracy, reliability and wide-linear range measuring. The effectiveness of the apparatus has been proved by in-house calibration and on-site test . The test result shows that it can be used in high voltage grid on-site calibration . Its measurement uncertainty can be limited to 0.1% under the condition of PF=1.0~0.8, and can reach 0.15% as PF=0.5. In summary, the apparatus discussed in this paper can be applied as high voltage electric energy measurement instrument to meet the requirement of online metrological verification and calibration. Furthermore, it is very useful for building the system of Advanced Metering Infrastructure (AMI) in smart grid.

We theoretically study light propagation in the two-dimensional arrays of mutually weak coupled waveguides. We study the properties of the discrete diffraction and demonstrate the existence of discrete spatial solitons in such arrays.

The steering radius and the vehicle velocity is utilized to control the drive force and steering angle of each electric-wheel in this essay. In order to improve the characteristics of vehicle, a dynamic simulation was made with the predictions of constant velocity and radius to the vehicle model with the R-v control strategy. This simulation proves that the characteristics of vehicle steering will be better with the utilization of this control strategy.