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Aiming at the problems in the modeling of assembly sequence planning, this paper proposes a assembly model based on the semantic and two-dimensional matrix which is easy to calculate and expression. The paper complement the parts attribute semantic and it is used to make the assembly model .So the parts about the attributes of parts assembly can be used in the ASP. Assembly relations including Assembly Precedence Relations (APRs), Contact semantic, Connection and Transmission semantic are transformed into a matrix model. Finally shaft structure is used as a example to represent a competitive advantage of this model.

To solve the problem of knowledge expression and reasoning model in expert system, factor neural network theory(FNN) is used in multi-expert system for oil-gas reservior protection.By introducing factor and factor space theory,knowledge expression model based on factor state space is presented.Fuzzy reasoning theory is utilized in the factor neural network to verify the effectiveness of the method and solve the reasoning problem of the expert system.The application of the expert system shows that factor neural network theory is valid in knowledge expression and reasoning model.Our proposed method based on FNN can effectively improve the accuracy of inference.

Porous asphalt pavement is widely used in domestic engineering, whose repair technology is still a problem in engineering application. Rut specimens for porous asphalt pavement are made, so the actual repairing condition of porous asphalt pavement can be simulated after slotting and repairing by open-graded cold mend material. In addition, the repair efficiency of open-graded cold mend material was verified. The results of the pullout test show that when the spraying dosage is 0.75L/m², the bond behavior of bonding oil is best excellent. The Accelerated Loading Facility (ALF) indicated that the cold mend material has favorable abrasion resistance properties, and the abrasion resistance is less effected by the spraying dosage of bonding oil. Meanwhile, it’s reveled that the permeability coefficient of rut specimen repaired by cold mend material decreases with the increase of spraying dosage of bonding oil in the permeability test, and too much bonding oil will seriously affect the rut specimen’s original permeability.

Catalysts play a critical role in the synthesis of carbon nanotubes. In this paper, we design a series of experiments to explore the impact of contents of Mo on the products. Analysis show, when the molar ratio of Fe: Mo: Al is 1: 0.2: 16, the carbon nanotubes show the best yields and quality.

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.

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.

Effect of iron ore tailings as fine aggregate on pore structure of mortars has been studied in this paper. The purpose is to investigate, as fine aggregate, comparing to natural sand, whether the iron ore tailings can improve the pore structures of mortars or not. Pore structure parameters were measured with the instrument of MIP and calculated with corollary software. The pore structure parameters from four kinds of mortars with different fine aggregates are compared with each other. This paper will provide more data about the use of this artificial aggregate, which may increase the feasibility of the use of this by-product in the mortar or cement concrete industry.

The recent local wars appeared a lot of information characteristics. In future wars, one who master information dominance in battlefield will become more active. In a sense, one who controls the information in the battlefield will grasp the whole initiatives in the war. In the paper, we have researched the methods of grasping the information dominance.

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.

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.