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This template analyzed the refrigerator condenser copper tube TP2 corrosion failure reason and compared the corrosion resistant performance of copper tube TP2, brass tube HSn70-1 and Cu-Ni tube B10. Copper tube corrosion is mainly caused by high concentrations of chloride, dirt and water scouring accelerated the corrosion process. The corrosion resistant performance of three copper tube is close to and unsuitable for the cooling water of the high salt content. A better corrosion resistance of stainless steel tube should be used as the replacement and needs to keep the purity of the heat exchange tube. For cooling water which easily causes fouling, the inside tubes should be smooth.

On the basis of modern technology of wireless communication and wireless local area network, a concept of Digital Human (DM) is put forward. DM change ordinary man-machine coordinated mode as DM-machine coordinated mode. Base on the discussion of the realization of DM, an innovated mode of digital shop floor manufacturing system is put forward also by introducing the mobile computing technology. Finally, the innovated mode of Man-Machine Coordinated Digital Shop Manufacturing system (MMCDSM) is presented. This paper also analyzes the network architecture and function module of this type of shop floor manufacturing system. Finally, integrating with multi-agent technology and workflow technology, a new methodology of role-based workflow modeling by utilizing multi-agent & DM is also put forward which can be applied in the MMCDSM.

In order to improve the block area and damage probability to targets, a new type warhead of circumferential cutter is presented. The optimization simulation is designed for the circumferential cutter warhead by using LS-DYNA finite element software. The detonation mode and the liner curvature radius are two important factors, which influence the formation process of circumferential cutting warhead. The result shows that priority should be given to use the upper and lower ends at the same time blasting technique. The shaped charge liner curvature radius and shot elevation ratio should be controlled in between 0.9 and 1.1.The warhead can be envisaged to achieve the desire of circumferential cutting.

According to the shortcomings of currently shooting range ballistic measuring method, the differential technique is applied in positioning system through analyzing the differential GPS technique to realize range ballistic high-precision measurements. This paper introduces the shooting range positioning system design and the realization of software terminal. This method overcomes the disadvantages of shooting range measurement .Positioning accuracy has indeed been improved through this way.

The component indicators of crude oil are very important in the field of oil transfer measurement. It is the parameters related to crude oil production. This paper describes a moisture/gas content of crude oil measurement system based on MCU and nuclear electronics. The measurement principle, the hardware circuits of the system and the analysis of the system error in the application process are introduced. This measurement system can realize non-contact continuous measurement, so it avoids pipeline corrosion environment on the measurement equipment. At the same time, it uses a low power MSP430F149 microcontroller chip, so it has high cost performance compared with similar measuring devices.

Reflow soldering process parameters have distinct effect on the lead-free reflow profile and its key indicators. To determine the relationship between reflow soldering process parameters and lead-free reflow profile is significant for obtaining the correct reflow profile. The result of orthogonal experimental shows that the most influential factors of the change rate of heat-up RS are conveyor speed S, temperature set value of the heating zone 1 T1 and the temperature set value of heating zone 2 T2 in sequence; the most influential factors of the soaking time TS are conveyor speed S, the temperature set value of heating zone 4 T4 and the temperature set value of heating zone 2 T2 in sequence; the most influential factors of the reflow peak temperature PT are conveyor speed S, the temperature set value of heating zone 7 T7 and the temperature set value of heating zone 6 T6 in sequence; the most influential factors of the reflow time TAL are conveyor speed S and the temperature set value of heating zone 6 T6 in sequence.

In order to study the influence of interface bond condition between new and old cement concrete pavement on overlay performance, the three-dimensional finite element model of the airport double-layer pavement was established. The pavement overlay's load stress and deflection were analyzed, the coupling coefficient between new and old cement concrete pavement was calculated based on the bottom of overlay deflection basin shape factor. The results show that the coupling coefficient reflects the degrees of interface bond condition well. Poor interface bond condition increases the overlay's load stress and deflection. The points that more closely distance from the wheels load center, the bigger the pavement overlay's load stress and deflection is. Therefore, more attention should be paid to the interface bond condition during the airport pavement overlay's designs and constructions.

The lunar soil excavation dynamics and control are complicated because of the high coupling among manipulator, backhoe device and lunar soil with uncertain parameters. To solve this problem, a multi-body dynamic model, regard the lunar soil backhoe device as the terminal link of the manipulator is developed using supposed link method, and then the excavation dynamics is modeling on the combination of the multi-body dynamic and Balovnev soil-tool interaction formula. Based on this model, an excavation trajectory tracking controller is realized via fuzzy-computed torque method. To reduce the affection of the excavation resistance to control precision, online lunar soil parameters estimation is held in the early stage of the excavation process, and the excavation resistance compensation, determined by those estimation results, is added to the tracking controller using feed-forward form. Simulation results indicate that the controller effective, which has the characteristics of fast tracking and high control precision.

In this article, the parameters affecting the quality of wire bonding are analyzed by orthogonal testing with the methods of variance analysis and F tests. By analyzing the results, parameters that have a major impact on the quality of wire bonding are optimized. Because the relationship is complicated and non-linear between the impacting parameters and bonding quality, this article introduces a neural network algorithm of BPNN to build a model describing it. The structural parameters of the neural network are identified and a quality prediction model of wire bonding is established in this article. The model is validated, the results show that this proposed model has higher precision and it can accurately reflect the trends of the bonding quality indicators.

To study the dispersion characteristic of photonic crystal, the eigen-equations matrix of the light transmitting in is gotten in plane-wave expansion method, then the dispersion curves are calculated for two dimensional air-hole-type square photonic crystal respectively. And the influence on the band structures caused by oblique incidence also is studied by change incidence angle. The results of calculations demonstrate that: For two dimensional square structure photonic crystals, the shape of the band structures of TE mode is very similar to that of TM mode, but their positions of band gaps are different, especially the first band gap of TE mode in the square structure in direction is completely staggered with that of the TM mode. Moreover, we get the conclusion that the width of band gap enlarges with the increasing radius of the hole in square photonic crystal in direction.

With the depth of space exploration and applications, the space robot self-assembling has become more and more important for space on-orbit service. Parameter analysis is an indispensable work of assembling process design. The dynamic model of the space robot with target is established firstly, then the Hertz model is introduced as the collision model between the docking link and the capturing cone, and the operational space control is applied to achieve the assembling operation control under the Cartesian space. Then the paper focuses on the discussion and analysis of the influences of the parameters such as the stiffness coefficient, friction coefficient, leading speed coefficient and vertical speed damping coefficient on the assembling characteristics. The simulation results would provide a basis for assembling control and parameter design and have an important academic value and engineering significance on space service.

Urban utility tunnel is an important type of underground space development, and also it is the requirement of Two-oriented society. In Laiyuan utility tunnel design, combining with the engineering practice, the designers properly solve the problems of pipelines crossings, meanwhile meeting the needs of pipeline s crossings layout plan, management and maintenance.