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In order to control deformation of foundation pit effectively and guarantee safety of building around, utilizing the stress characteristics of arch, use the new spatial retaining structure of arc row piles with arc ring beam on the pile top. The arc ring beam can provide constraint to pile top, so internal force of pile body distribution is uniform, and improve the integrity stability of piles. The ring beam with compression mainly can give use of high compression capability of concrete. According to the high order statically indeterminate characteristics of the retaining structure, calculation model of ring beam and pile respectively is established by the redundant forces between beam and pile top. By using deformation compatibility to set up flexibility equation of the retaining structure, and solve the redundant forces, then calculate the internal force and displacement of ring beam and piles. Through calculating the practical engineering, research the effect of excavation depth on internal force and displacement of piles and the arc ring beam on the pile top.

Optoelectronic industry is one of the pillar cornerstone industries in the 21st century. For China optoelectronic enterprises, how to participate in the global competition by means of the world-class quality has become the survival or perish subject. Based on the analysis of optoelectronic products and its quality management characteristics, this paper proposed the product lifecycle quality management model which is customer demands-driven and six sigma process control targeted by emphasizing the process control based on fact and data. This paper suggested and illustrated the prototype system of optoelectronic product lifecycle quality management combined with the actual quality management for demonstrating the feasibility of model.

on doping is an effective means to improve the performance of LiFePO4 material. In the present study, composites LiFe (PO4)(1-x/3)Fx/C (x=0.00,0.02,0.04,0.06,0.08,0.10) were synthesized by carbothermal reduction method. The as-synthesized samples were characterized by X-ray diffraction and scanning electron microscope, and their electrochemical performances were investigated by constant current charge-discharge experiment. The results indicated that the low concentration F dopant did not affect the structure of LiFePO4 but considerable improved its electrochemical performances. The LiFe (PO4)0.98F0.06/C materials showed better electrochemical performances than LiFePO4/C. At 0.2 C discharging rate, the LiFe (PO4)0.98F0.06/C materials was capable of delivering reversible specific capacity of 165.1 mAh/g, with fairly stable cycleability. The excellent performance indicates that this mix-doped composite was a very promising cathode material for lithium ion batteries.

The North Ustyurt basin, located in Central Asia, is an important gas-bearing potential area, but the gas source has been the key difficult point. Based on the geo-chemical analysis of Jurassic mudstone samples and research on the petroleum geology, the qualitative evaluation was conducted, it proposed that middle Jurassic source rock was dominative hydrocarbon-generation source rock for relative high organic matter abundance and maturity compared to upper and lower Jurassic source rocks. According to the thickness distribution of dark mudstones, Kosbulak sag, Sudochi sag and Barsakelmes sag were preferable hydrocarbon-generation sags.

This article studies the performance of ceramic grinding wheel made of micro-crystalline alumina in the creep feed grinding of nickel-based superalloy Inconel 718. The effects of abrasives and specific pore volume on the performance of wheels are experimentally discussed. Grinding force and temperature were measured and analyzed during grinding tests. The surface roughness was used to describe the quality of ground surfaces. The results indicate that the micro-crystalline alumina SG abrasive wheel with large specific volume has good grinding properties when grinding Inconel 718 in comparison of the wheels with PA abrasives or SG abrasives of small specific pore volume.

In order to ensure the safety of production, a new method for strengthening pipe with carbon fiber reinforced polymer sheet is introduced. The experimental research on the effect of this method has also been done. In the experiment, the pipe that wrapped with one and two layers of CFRP sheets respectively are tested. And the relation between the hoop strain in the tested pipe and the internal water pressure is given according to the experiments. The results show that it can be a substantial increase in the bearing capacity of the pipes. The construction of this method is simple and a short period is required; so it not affect the normal operation of generating unit. It has a good practical value in the production practice.

In order to improve the SINR of the beam-former in the case of DOA mismatch, the paper raises the probability of constraint beam-forming algorithm based on mutative scale chaos optimization in connection with the worst performance of the best sound beam-forming algorithm. By introducing the probability constraints confidence interval and the signal vector error distribution law in the beam-forming, the constrained optimization problem is eventually turned into a nonlinear optimization problem. Then the global optimal weight is searched by the mutative scale chaos optimization method. Simulations have shown that the algorithm can significantly improve the SINR.

According to the testing craft and requirements of CNC Lathe about main spindle box, testing system of hardware and software structure was designed in this paper. It adopts sensors, data acquisition cards, industrial control computer, frequency converter and so on as hardware, good data analysis methods, and LabVIEW as software tool, to realize real-time monitoring of main spindle box testing conditions.

This paper describes SolidWorks secondary development based on VB.NET and focuses on introducing design process of automatic checking of three-dimensional hydraulic manifold block. The auto-checking process achieves automatic checking, establishes an excel table automatically and writes oil hole information, intersecting hole numbers, and phase interferential holes into the excel table successfully.

This paper focuses on a general weight lightening method of machine tool's key moving parts based on frequency topology optimization and dimension optimization using Ansys workbench and Ansys classic interface. First, preparations of frequency topology optimization, including setting material, applying constraints and loads, meshing of the high-speed turning center HTC2550hs slide board were done in Ansys Workbench; Second, frequency topology optimization was performed in Ansys classic interface, and the preliminary light weighted model of the slide board was obtained; then, for important parameters of the removal parts that affect slide board's dynamic performance much, dimension optimization was performed. Finally, we achieve that the slide board's weight is reduced by 11.03%, while its first and second natural frequencies are increased.

The effect of Y addition on the microstructure of AZ61 alloy was investigated by optical microscopy (OM), X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). The corrosion behavior of AZ61 alloy with Y addition in 3.5 % NaCl solution was studied by static weight loss and polarization curves corrosion tests. The results show that AZ61 alloy with Y addition can refine grain size of the matrix and alter the distribution of the phase β-Mg17Al12from continuous network morphology transition to small and dispersive distribution along the grain boundary by forming the second phase Al2Y which has a high melting point. In addition, the addition of Y can decrease the corrosion current density of AZ61 magnesium alloy in 3.5% NaCl solution, thereby improving the corrosion resistance of AZ61 magnesium alloy. Results show that AZ61 magnesium alloy with 1.0% Y has the most refined microstructure and the best corrosion resistance.

Based on the analysis of the product design and its process, by using Top Basic Skeleton (TBS) model as a link, and adopting eXtensible Markup Language (XML) to the product’s top-down design and the description of the information evolution, this paper defines the transfer process and the structure of the document of the information transfer in TBS modeling process, and describes the transmission of the design information layer by layer. As a conclusion, the combination of the TBS and XML is beneficial to control the product design process, and to do variant design.

Transparent poly(methyl methacrylate) (PMMA)/TiO2 nanocomposites have been prepared by solution mixing PMMA with organically soluble titania xerogel. The organically soluble titania xerogel in the form of amorphous phase has been synthesized via a simple sol-gel method, involving hydrolysis of tetrabutyl titanate (TBT) in trifluoroacetic acid (TFA) and gelation. The obtained PMMA/TiO2 nanocomposites were characterized by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscope (TEM), thermogravimetry (TG) and ultraviolet-visible (UV-vis) absorption spectroscopy. The results showed that the interaction between titania nanoparticles and PMMA macromolecular chains led to a homogeneous dispersion of TiO2 in PMMA matrix. The resulting PMMA/TiO2 nanocomposites showed improved thermal stability, high transparency and high UV-shielding efficiency with a small amount of titania xerogel (£3.0 wt%). The present work is of interest for developing a series of transparent UV-shielding nanocomposites.

The necking-in product is widely used in many fields in the world. An improved necking-in machine is introduced in this paper. Matlab/Simulink is the popular simulation software in the dynamic system simulation field due to its powerful computing capability. DSHplus is the hydraulic special simulation software with graphical programming environment and abundance of model libraries and the system model can be built quickly. The co-simulation of DSHplus and Matlab/Simulink can take the advantage of their merits, which can study the control algorithm that applied on the hydraulic proportional system better. The Fuzzy PID control algorithm can apply logistic inference to tune the PID parameters automatically according to the working condition, which can solve many engineering problem of high performance requirements. So the Fuzzy PID algorithm is applied in this paper to improve the performance of the hydraulic system.