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With the new equipment research preparation put into use, in order to ensure special purpose forces, in the existence of a large number of new equipment nonstandard parts. These non-standard parts in the various aspects of the new equipment play a great role. This topic-based VIRTOOLS 5.0 software to establish a non-standard parts library in new equipment, new equipment, used to strengthen the management and maintenance of non-standard parts for the maintenance of armed forces provide a solid guarantee. Meanwhile, from the user maintenance reality, virtual assembly of non-standard parts, non-standard parts for the maintenance provide effective protection.

In order to provide theory basis and experimental evidence for optimizing milling parameters, the cutting force prediction models for milling of Ti6Al4V with uncoated cemented carbide tool were built based on single factor method. The significances of the cutting force prediction models were checked. The effects of milling speed, feed per tooth, milling depth and milling width on cutting forces were also studied. The results show that the built prediction models can be applied effectively to predict the cutting forces in milling of Ti6Al4V in the experiment parameters range. Milling depth has highly obvious influence on cutting forces among these milling parameters. The cutting forces decrease with the milling speed increasing, and increase with feed per tooth, milling depth and milling width.

Environmental cross-wind has a influence on cooling capacity of wet cooling tower to a great extent in power plant.The variation of circulating-water temperature difference (Δt) and cooling coefficient of efficiency(η) with cross-wind velocity, circulating water inlet temperature and flow rate, are shown under cross-wind conditions, compared with cases without wind. By using experimental platform of cooling water system based on 300MW thermal power unit,it is found that with cross-wind velocity increasing,cooling temperature difference and cooling efficiency decrease first then increase at the knee point when the velocity value is 0.8m/s. In addition, the correlation betweenΔt ,η and parameters,such as circulating-water inlet temperature and flow rate, is derived for cases with windless conditions.

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.

Rock mass is the syntheses composed of kinds of structure and structured surfaces. The joint characters is influencing and controlling the rock mass strength, deformation characteristics and rock mass engineering instability failure in a great degree. Through using the RFPA2D software, which is a kind of material failure process analysis numerical methods based on finite element stress analysis and statistical damage theory, the uniaxial compression tests on numerical model are carried, the impact of the trace length of rock joints and the fault throws on rock mechanics parameters are studied. The results showed that with the gradual increase of trace length,compression strength decreased gradually and its rate of variation getting smaller and smaller, the deformation modulus decreased but the rate of variation larger and larger; with the fault throws increasing, the compression strength first increases and then decreases, when the fault throw is equal to the trace length, the deformation modulus is the largest. When the joint trace length is less than the fault throw, the rate of the deformation modulus is greater than that of trace length, but the deformation modulus was not of regular change.

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.

In order to study the effect of tire operating mode on its safety performance, a high-speed tire test-bed was put forward. The dynamic characteristic of drum was important for test result. To avoid the resonance of loaded drum during operation, the topological optimization analysis of drum with I-shaped structure was fulfilled with the element density as variables and the volume reduction of fifty percent as constraint condition and the first natural frequency as objective function. The optimal density distribution of drum was obtained within the constraint of the first natural frequency. Based on the analysis result of topology optimization, the drum structure with I–shaped was modified. The structure size of the new and improved drum was optimized with 50 iterative calculations using ANSYS. On the condition that the first natural frequency of drum was over 60Hz, the structure size of drum was optimal when the rate of the first natural frequency and total weight was highest and equaled to 0.05391. The optimization results showed the first natural frequency of drum was raised by 21.972Hz and its total weight was reduced by 69.95Kg.

In order to analysis the processing and serviceability of soybean protein-PVA fibers, the thermal property is studied by TG and DSC and other methods. The result is compared with that of the wool. The glass transition temperature of soybean protein-PVA fiber is 81°C.The decomposition temperature is 313°C.The heat dry air shrinkage rate is 2.3%. The heat endurance meets with the demand of processing and end use.