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Ha Tai railway passenger dedicated line is a national key project of the eleventh five-year plan. Its different from other construction of high-speed railway because there is many frozen soil over the place. The requirement of the subgrade material is higher.We proposed a idea that gradred broken stone mixed with cement and fine powder applied in the project.The compressive strength,splitting tensile strength and flexural strength were studied and analyzed through laboratory test.And regression analysis between compressive strength and flexural strength was made .According to the regression analysis,a power exponent function between flexural strength and compressive strength was got.Based on this,the corresponding relationship table was deduced,which can be used in practical projects.

ion: In gas difference absorption detecting system, the output electric signal is very faint and submerged in the background noise. In order to extract the faint signal covered by the background noise, we design the detective circuit aiming at how to restrain the noise and improve SNR of the system. In this paper, the detection circuit centering lock-in amplifier which reference signal frequency is automaticly followed is designed. The circuit adopts synchronization cumulating and locked loop technic, carries out frequency and phase aotomatic follow to the measuring signal by a locked loop circuit. The circuit not only avoids the tache taking reference signai from the modulator then adjusting the phase shif, but also improving signal-to-noise ratio more by synchronization cumulation.

Chemical mechanical polishing (CMP) has been a widely applied process for nickel-phosphorus (Ni-P) coating hard disk substrate polishing. In this study, colloidal silica-based alkaline slurry was prepared for polishing Ni-P plated substrates and its CMP mechanism was studied with alkali slurry. Effects of the various process parameters such as polishing pressure and plate speed on hard disk substrate were investigated. The results show that the polishing pressure and plate speed have a strong influence on the material removal rate and surface roughness of the hard disk substrate. The oxidization layer formed on hard disk substrate surface after polishing. The nickel ions were bounded with amidocyanogen to form stable and soluble macromolecular amidocyanogen-complex agent, improved selectivity of convex region and concave region, enhanced the chemical reaction uniformity and the mass transfer velocity, and thus high removal rate and low surface roughness could be realized.

Abrasive jet precision finishing is a new machining method, which injects slurry of abrasive and liquid solvent to grinding zone under without feed condition. The machining is simulated by Finite Element Method (FEM) in the paper. Hydrodynamic pressure on modeling of wedge-like grinding zone between wheel and workpiece on abrasive jet finishing with wheel as restraint was established and simulation, based on Navier-Stokes and continuity equations. The liquid hydrodynamic pressure distributing principle and affecting factor were investigated. The relation hydronamic pressure with grinding wheel velocity was stimulated and verified experimentally. The experiment results show that the simulation results are agreement with experiment, so the simulation model can well forecast hydrodynamic pressure distribution at contact zone.

The surface morphologies, chemical composition, phase composition, compactness, thickness and the corrosion resistance of porous anodic films prepared in the sulfuric electrolyte with different additives at 35°C were investigated by XRD, FESEM, EDS, drop method in this paper. The additives are including organic acids, polyhydric alcohols and rare earth (REE) salts. It is indicated that a porously anodic film with about 20 nm holes in diameter can be obtained by additives into the sulfuric electrolyte. The main chemical compositions of the anodic films are Al, O elements, and a small amount of S. The film after boiling water sealing is composed of boehmite phase (Al₂O₃·H₂O) and alumina (Al₂O₃). The corrosion resistance of the anodic film can be improved by the coupling effect of the additives. The mechanism is discussed.

Copper wire continuous annealing is a key process of the cable production line. The accuracy of the temperature control directly determines whether the quality of copper wire meets the requirements. In this paper, the fuzzy-PI compound controller was selected and the structure of the annealing temperature fuzzy-PI control system was designed based on temperature measurement. Through the simulation of traditional PI control system and the improved Fuzzy-PI control system, the results show that the Fuzzy-PI controller is better than traditional PI controller. It verifies the feasibility and effectiveness of the Fuzzy -PI controller and proves that Fuzzy-PI algorithm can be successfully applied to the copper wire continuous annealing temperature control system.

In order to analyze the process of mechanical-electric brake of electric drive tracked vehicles accurately, a dynamic/kinematic model which based on multi-body dynamics software RecurDyn, and a control system model based on Matlab/Simulink were established. Both of the two models are co-simulated through the software interface technology. The brake process of the drive motor that based on vector control technology is analyzed.

Synthesis of titanium dioxide sol was prepared by sol-gel method, using tetrabutyl titanate as source, ethanol as solvent, acetic acid as complexing agent. A transparent sol aging in air 30min, titanium dioxide films were prepared by using spin coating method. Congo red degradation was investigated by TiO₂ photocatalysis. Study the efficiency of decolorization was influenced by the coating times, heat-treated time, the initial concentration of congo red and solution pH.

Semi-solid thixoforming process was applied to produce track shoe of 15%SiCp/2A14 composites. The thixoforming process optimization was simulated by using Deform 3D software. The effects of forging pressure, slug size and reheating temperature on formability of track shoe were investigated. The results showed that a track shoe with better integrity was prepared by optimizing the process, and its microstructure and mechanical properties could meet requirements.

This article is based on the theory of fractional calculus control, and put forward a kind of fractional order PI controller design method for lateral attitude control system of unmanned aerial vehicle (UAV) model. And the unit step response of the control system is analyzed in the simulation to improve the UAV flight control system stability and robustness. Use the controller parameter tuning method and combined with fuzzy reasoning to design IOPID controller, FOPI controller and fuzzy fractional order PI controller. Then, by exploiting Matlab, the frequency domain response and unit step response characteristics of the different control systems can be plotted. The results verified that the designed fuzzy fractional order controller for the attitude control system is effective.