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This paper presents the analytical compliance analysis and type synthesis for a tripod flexure mechanism (TFM) which is used in the design of the mirror sub-assembly (MSA) of future inertia-confinement-fusion (ICF) facilities. To reveal the compliance characteristics of the TFM, the static compliance analysis is conducted. The analytical compliance matrix of the TFM is obtained by using the coordinate transformation method (CT-method) of compliance matrices. The parameterized compliance matrix of the TFM is derived, and it is significantly influenced by its legs’ mounting angle θ. Different θ values generate different degree-of-freedom (DOF) characteristic of types. The finite element analysis (FEA) results are compared with analytical compliance elements results for different θ values. As to the linear linear-elastic deformations, the maximum compliance error of analytical model is less than 1% compared to the FE model. Enlightened by the compliance analysis of the TFM, a compliance-based type synthesis of the TFM is introduced in detailed processes, illustrating how θ affects the DOF characteristics. According to the results of the compliance analysis and type synthesis, a TFM was designed and fabricated for the MSA prototype, and it is experimentally verified. It is demonstrated that the parameterized compliance matrix provided is beneficial to design, analysis and type synthesis tasks of TFMs.

As a new experimental technique of aerodynamics, optical flow test technique gradually attracts more and more attention for the advantages of vector field measurement of pixel scale resolution and strong smoothness ability. By means of scalar constraint equation combined with smoothness constraint condition, optical flow test technique can measure global velocity vector field of high space resolution. In this paper, the theory and algorithm of integration minimization optical flow velocimetry were studied, an verification experiment, in which tracer particle images was acquired by high speed camera and velocity vector field was calculated by optical flow algorithm, was completed. The result calculated by optical flow algorithm was compared with the result calculated by PIV algorithm, and both results were significantly correlated. The research shows that optical flow test technique possesses the advantages of space resolution and velocity field smoothness.

Morphing UAV(Unmanned Aerial Vehicle) change its profile to adapt for wide flight condition, and attach lots of flight tasks, so PID controller is needed to satisfy the morphing requirement of UAV. Firstly this paper shows the expression of morphing aerodynamic process. Then, characteristic values of UAV are analyzed, and PID controller is brought out to satisfy stable capacity of UAV closed system. At last, simulation is run with traditional PID controller, and the best morphing time can be got from time sets.

This paper will present a summary of the target area structural design results of ShenGuangIII (SGIII), which includes target bay and switchyard support structures, target chamber, and beam transport system. The target area building is rectangular and includes a target bay and a switchyard. The outer wall of the target area building is based outside the vibration isolation trenches and separates the diurnal temperature loads and the wind loads that occur outside the target area building during the alignment process prior to a shot. The target bay and switchyard support structures are mainly comprised of the steel reinforced concrete building and the steel space frame. The target chamber is a welded sphere made of aluminum alloy 5052 and has an inner diameter of 6 m and a nominal wall thickness of 8 cm. The beam transport system brought the 48 laser beams to the final optics assemblies (FOAs) and includes 276 transport mirrors. Sources that influence stability are mainly ambient random vibration, ambient wind induced vibrations, diurnal temperature changes, and HVAC. A FEM is used to calculate the responses of the target area structure under broadband ambient random vibration. The position deviations of 48 beam lines are calculated and used to evaluate the stability of the target area structure. The analyses demonstrated that the positioning deviations of 48 beam lines satisfy the deviation budget requirements.

Operating posture of complicated opto-mechanical structures critically matter gravity-induced distortion of the structure, and further affect optical performance. With the aim to solve this problem, determination of operating postures of a supporting system of a KDP crystal is studied. A concept of key stiffness component is firstly proposed in this paper, as far as the authors are concerned, taking advantage of which gravity-induced distortion of the supporting system is analyzed, as well as the rotation of the KDP crystal that is cased by the distortion of the supporting system. Furthermore, effects of operating postures of the supporting system on the distortion of the supporting system and the rotation of the KDP crystal are investigated. It is demonstrated that key stiffness component is of great insignificance to distortion of the supporting system, and it could function as a guidance in determination of operating posture of the supporting system.

A novel infrared image edge detection algorithm based on cellular neural networks on FPGA is proposed.First,the infrared image input module is to build with simulink.The relevant information of infrared image head is acquired,and the infrared image pixel value range is adjusted.Then CNN IP core is designed by lookup table which is created by the template of cellular neural networks.With the regularity and interconnection locality of cellular neural network array,the CNN IP core will be expanded into the cellular neural network array.Then the cellular neural network array is related with the infrared image input and output module by modelsim,so that the infrared image will be processed in real time.The experimental results showed: In the field programmable gate array hardware processor platforms such as the Virtex-6 FPGA of the Xilinx,the infrared image edge detection algorithm will be implementationed with cellular neural networks.The highest frequency of 142.693MHz is got,and the system processing speed of 2.378Mpixels/sec is reached.

To assure the pointing accuracy in a shooting target to be better than 30 μm for the Shen Guang Ⅲ(SGⅢ)facility,the switchyard of target area for the facility was designed and the rigid frame and transport mirrors in the switchyard were optimized to improve their stability.In design,the reinforced concrete was used to support the switchyard,and the tilted supports were added in the steel frame of switchyard to decrease and distribute the mass load reasonably.Furthermore,the herringbone supports were firmed to local horizontal beams.The transport mirror supports were also designed,in which their foundational frequencies were much higher than that of the swichyard.By above ways,the angle shifts of transmission mirrors in random broadband vibration can be suppressed successfully.The mechanical analysis of range structure by Finite Element Analysis(FEA) indicates that 87% of transport mirrors show their angle shifts less than 0.48 μrad.According to the relation between the rotation drifts of the optics components and the positioning errors of optical path,it can be seen that the rotation drifts of the transmission mirrors could meet the stability requirements for the positioning error of each single optical path not more than 12.9 μm.

Influence of radiation force of a high-energy laser beam on the second harmonic generation (SHG) efficiency through stress within a mounted potassium dihydrogen phosphate (KDP) crystal is studied, as well as an active method of improving the SHG efficiency by controlling the stress is proposed. At first, the model for studying the influence of the radiation force on the SHG efficiency is established, where the radiation force is theoretically analyzed, the stress caused by the radiation force is theoretically analyzed and numerically calculated using the finite-element method, and the influence of the stress on the SHG efficiency is theoretically analyzed. Then, a method of improving the SHG efficiency by controlling the stress through adjusting the structural parameters of the mounting set of the KDP crystal is examined. It demonstrates that the radiation force causes stress within the KDP crystal and further militates against the SHG efficiency; however, the SHG efficiency could be improved by controlling the stress through adjusting the structural parameters of the mounting set of the KDP crystal.

We report applications of a metallic film and a phase matching layer (PML) to increase the reflectivity of the cavity mirror in a long-wavelength InP-based vertical-cavity surface-emitting laser (VCSEL). The synthesis of the InGaAsP/InP distributed-Bragg reflector (DBR) with an Au film and the InP PML leads to the decrease of periods of the DBR multilayer stacks from 33 to 20 while keeping the reflectivity of the structure over 99%. The reflectivity over the whole forbidden band is significantly increased and become flatter compared to the bare DBR. The use of smaller DBR periods in a long wavelength VCSEL makes the epitaxial growth well controllable, decrease of the heat resistance, and decrease of the in-series electrical resistance of the devices. This can improve the reliability of the VCSEL growth and possibly cut down the cost of VCSEL devices.

A novel small-sized chip circuit auxiliary layer (SCCAL) multipurpose 3D package process in order to solve the problem of shortages in flexibility and diversity of the traditional through-silicon via (TSV) process is presented in this paper. It meets the requirement of large amount of silicon dies which need connecting together by TSV technology but were designed respectively that wafers were processed without via holes drilling. This process involves a small-sized chip circuit auxiliary layer which is used as a carrying base and connecting auxiliary layer. Also, an improved TSV technology is involved that via holes could be produced through the PADs in the silicon dies. It is verified that, the whole process time of 3D packaging process is shortened drastically and the flexibility of the 3D packaging is greatly improved.

Based on the bibliometric method, this paper analyzes statistically the research papers on anaerobic wastewater treatment in China collected by China Journal Whole-length Database of National Knowledge Infrastructure (CNKI) published during the period of 1998–2008. Yearly distribution, core author, paper cooperation, institution distribution, journal distribution and topic distribution are analyzed, reflecting the status of scientific researches on anaerobic wastewater treatment in China.

FL network architecture is a supervised learning extension of the BP network method we have studied thus far. It allows specification of the category into which inputs will be classified. In the designated category, the training set is extended into the input pattern of single layer perceptron with nonlinear change. It is high efficient in the aspects of processing speed and avoiding local stability, and especially useful in fault diagnosis.

The cap layers of InAsP/InP SMQWs and InAsP/InGaAsP strained single quantum wells (SSQW) are etched to different depths using ICP. The PL intensity of the quantum wells is enhanced by different degrees after dry etching. The quantum well surface becomes rough and the microstructure inside the quantum well is changed during dry etching. The influence of surface roughness to the photoluminescence of quantum well is eliminated by selectively wet etching the InP cap layer of the SSQW. It is attained that after the cap layer is dry etched off about 20 nm the PL intensity of SSQW is enhanced about 1.8 and 1.2 times due to the change in microstructure and the roughening of surface, respectively.