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To obtain the improvement of analog circuit fault diagnosis, a RBF diagnosis model based on an Adaptive Genetic Algorithm (AGA) is proposed. First an adaptive mechanism about crossover and mutation probability is introduced into the traditional genetic algorithm, and then AGA algorithm is used to optimize the network parameters such as center, width and connection weight. The experiment simulation indicates that the proposed model has exact diagnosis characteristic.

Based on analyzing the characteristics of engineering design enterprises, through investigating 30 Chinese design enterprises ,the present main engineering design service modes are summarized and analyzed, furthermore the backward management philosophy, lack of the efficient information feed back mechanism ,and no enough attention to the accumulation of knowledge are uncovered as the root causes of low innovation ability, the design defects, and extensive management in Chinese design enterprises. Under the great changes taking place in modern market environment, the Chinese engineering design enterprises are required to transform for complying with market demands and the world trend, so the life cycle design service mode is put up with the development strategies for the development of the engineering enterprises.

This article constructed the stress distributions function expression of four free edges square basal bottom slab touching foundation respectively from the two aspects of symmetric and anti-symmetric load, placed the foundation on the surface of the sandy soil, do numerical simulation to the contact stress between foundation slab and foundation through the large scale finite element analysis software ANSYS, and fitting by adopting the contact stress function proposed in this article. The contact stress function and finite element numerical fitting result shows that the contact stress function proposed in this article can better reflect the actual contact stress distribution, also adapt to foundation slab with different width height ratio.

The maglev chopper is a very important part in the maglev train technology. This paper briefly analyses the working principle of a kind of two-quadrant zero-transition soft-switching maglev chopper, discussing the choosing of the key parameters, also with the experimental study on the choosing of the switching-on time, the experimental results indicate that, if you choose the switching-on time correctly, the pulse spike and ripple wave at the switching-on time is decreased, the resonance degree is subdued, and the efficiency is improved.

Under the e-commerce environment, the increasing competition in the logistics market has been obviously. As the main force of Chinese logistics market, the small and medium-sized logistics enterprises who want to achieve further development should implement the common delivery, which has been turned out to be the short way to improve logistics efficiency, to enhance the competitiveness of enterprises and typically to optimize the allocation of resource. This paper proposes a new type of common delivery mode, the uniqueness of which is that it integrates the existing model while dealing with the decentralized urban common delivery management problem. The paper also proposes a new design step in the design of the common delivery system, and as the result of the simulation with the software Flexsim, the design, which also has the potential to coordinate the behaviors in decentralized supply chain environments, can meet the needs of a large number of goods.

To improve the performance of Wavelet Neural Network (WNN), a hybrid WNN learning algorithm, which is combination of Genetic Algorithm (GA) and Chaos Optimization Algorithm (COA) in a mutual complementarity manner, is proposed. In the algorithm, GA is first used to roughly search the optimal parameters of WNN as a whole, and then COA is adopted to perform the refined search on the basis of the result obtained by GA, which can make remarkable progress in modeling accuracy, learning speed, and overcoming local convergence or precocity. Simulation show its effectiveness.

It has an great significance for making heat treatment technology by researching the law of temperature variations of ductile iron in austempering. Based on the three-dimensional finite element method (FEM), the temperature variations of low alloyed bainite ductile iron in austempering are studied in this paper. The temperature relativity of the thermal physical parameters is considered during building the model. The simulation result demonstrates that during the stage of rapid cooling, the cooling speed of the surface is faster than that of the center, and the whole cooling speed increases firstly, then decreases. During the stage of isotherm, the surface temperature of the sample increases to the isothermal temperature directly, while the center temperature decreases firstly, then increases, until to the isothermal temperature.

Cationic styrene-acrylate latex as surface sizing agent had been prepared with the emulsion polymerization by use of styrene, dimethylaminoethyl methacrylate, 2-ethylhexyl acrylate, modified PVA 0588 as the emulsifiers. The infrared spectrum of copolymer and particle size and physical properties were separately determined. The results indicated that the obtained copolymer emulsion was very stable, the average molecular weight of copolymer approached about 45000 and polydispersity index was 1.6. The copolymer with higher quaternization degree had smaller particle size and narrower particle distribution when initiator had the same usage. The copolymer as surface sizing agent improved the hydrophobicity of paper, the water-proofing time approached 14.7 seconds at most, the copolymer with narrow particle distribution increased 7% sizing performance than the one with wide particle distribution.

This article analyses the theories of two methods of matrix displacement and finite element, and the application of calculation in the actual structure. Then it explores the subtle differences between them: Matrix displacement method can only be used for analysis with known unit nodes force-unit nodes of the relationship between the displacement of the truss structure, and not the continuous body structure. The major differences between both are the establishment of the basic principle and solution of the emphasis. Establishing total stiffness matrix according to the geometric property of the structure and then forming integral force vector via loading conditions when matrix displacement method is used to solve the unit fixed-end force. It’s necessary to stack fixed end force; While finite element method mainly bases on the known load and the material nature of structure after structure discretization. Node force or node stress is directly got by the derivation of displacement, but the fixed end force is lost, which dropping the accuracy of the stress. To solve plane frame structure and get structural internal force, the distinguish is checked on the example.

Statically indeterminate frame, composed of beams and columns, is a widely used structure form in civil engineering. The frame carrying capacity under various actions is related to the absolute stiffness of frame components and relative beam-column line stiffness ratio. The matrix displacement method and programming based on MATLAB were employed in this study to calculate the internal forces and displacements of a 2-bay 2-story frame structure under the action of horizontal loads. The influence of the beam-column line stiffness ratio on the frame load capacity was discussed based on the calculated result. Furthermore some advises were provided about the reasonable beam-column line stiffness ratio for engineering design.

In this paper, the analytical solution to the planar magnetic field of a linear permanent magnet Halbach array is researched on. First, the magnetic field of a current surface is derived from the magnetic field produced by the molecular current of the permanent magnet. The magnetic fields of pieces of permanent magnet with vertical and diagonal magnetization direction are both solved by combining the magnetic field of current surfaces with different directions. Then the planar magnetic field of the entire linear permanent magnet Halbach array is obtained by calculating the vector addition of the magnetic field of all the permanent magnet cubes using Denavit-Hartenberg (D-H) transform technique, which yields the closed-form analytical expressions. The analytical algorithm proposed in this paper can be utilized to design and optimize the Halbach array, which in result can greatly simplify the calculation and expedite the progress. The effectiveness of the proposed method is evaluated by the finite element analysis software Maxwell.

The control of particle size and its distribution has become more and more important both in theory and in practice of emulsion polymerization field. In this study, cationic styrene-acrylate copolymer containing functional monomer was converted into water-soluble polymers by reaction with quaternising agents and acids with the free-soap emulsion polymerization method. The latex was obtained at the existence of nitrogen by the copolymerization of hydrophobic monomer styrene and 2-ethylhexyl acrylate, hydrophilic monomer dimethylaminoethyl methacrylate, modified PVA-0588 as the emulsifiers. The influences of the amount of azoisobutyronitrile initiator, the amount of dimethyl sulphate quaternising agent, reactivity ratio between monomers, charge density and pH value on the preparation process were discussed. The particle size and particle distribution was strongly affected by these factors. The results showed that the latex with narrow particle distribution and mean particle size about 100nm was obtained under redox system by adjusting 33% monomer to become precursor and dropping the rest of 67% monomer, after polymerization, N,N-dimethylamino groups were fully quaternised with dimethyl sulphate to improve the stability of the solutions. The glass temperature of polymer was 58.1°C, as pH values range of solution was 3~5, the stability and charge density of polymer emulsion could improve.

A certain type of radar was equipped in the main fighter jets. It is main equipment which can ensure the completion of the task of the fight in the air. But at present, this type of radar transmitter outside the room does not have special test equipment and the manual testing process is also more complicated. So, to achieve rapid testing of this transmitter for technician and improve the measurement’s accuracy, need a new system. In this new system used bus control technology, virtual instrumentation technology and database technology. Besides these, brought them to combine organically, then we get the system with fault diagnosis, detection intelligently and the test database. In order to achieve test and communication with radar transmitters, the system used the MIL-STD-1553B bus as a control bus, the USB bus as a program-controlled instrument control bus and in LabWindows/CVI 8.5 development environment designed software of the system. After a trial showed that the system reached the requirements of the test specification.