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A method of molten salt replacement was used to prepare an Al coating on Mg-Li alloy at different temperatures. The thickness, microstructure, phase composition and corrosion electrochemical analysis of the coating treated at different temperatures were analyzed. The corrosion resistances of the specimens with and without optimal coating were comparatively evaluated. Results show that, the optimal treatment temperature is 350 °C, at which a thickness of 9.15 μm coating is formed. In the Al coatings, Al exists as the form of Mg17Al12 and AlLi. The corrosion resistance is much better than that of the specimen without coating.

This article introduces the machining mechanism of rolling process and analyzes its influence on hardness, abrasion performance and fatigue strength of the work piece.

With the development of Radio Frequency Identification technology in recent years, it has been successfully applied to all areas of life. This article mainly elaborates the concept of RFID, system components, tracking and detection of machining processes and some other applications workshop production and management. It also puts forward the problems of RFID in machining and the application of RFID in machining for further prospects.

Screw refrigerators are widely used in subzero refrigeration and storage fields. The manufacturers always use rotor-type pumps as their lubricating oil pumps. This paper introduces the advantages of screw refrigerators, the usage of oil pumps and the working environments. It mainly studies the common faults of oil pump, proposes several design ideas for analysis and comparison and determines the final improvement schemes on the premise of comprehensively considering structure, performance and cost.

Common welding defects in ship building and ship repair were intro-duced; the forming mechanisms, distributions and forms of expression of the defects were analyzed, Foundry-Techniques for preventing kinds of defects were given and common methods and application scope of ship welding inspection were concluded.

The lunar soil simulants using for vehicle-terramechanics research on the ground need to expose in air containing water molecules for a very long time. The influence of the engineering properties of lunar soil simulant caused by air moisture should be determined. This paper has obtained the moisture absorption of JLU-1, JLU-2 and SNJ-4 using weighing method. The result indicates that the hydroscopicity of three lunar soil simulant are: SNJ-4>JLU-2>JLU-1, all less than 2%. It shows that even in saturation state, the moisture content of three specimens is very little. The length of storage time of lunar soil simulant in natural environment has little effect on its engineering properties. Lunar soil simulant after be made can be storaged well for a long time in the natural environment, and used for ground foundation test. The results can supply the reference to evaluate the engineering properties and formulate the suitability standards of lunar soil simulant.

In order to improve the processing properties of corn ear and the utilization of drying equipment, and reduce energy waste, a set of multi-purpose drying systems which using the piecewise drying process was designed. It was divided into dry storage and wet storage according to the different moisture content of corn seed .The wet storage worked with minor-cycles drying, and the dry warehouse worked with a large circular drying. The corn ear was unloaded and delivered to threshing area for threshing operations when its moisture content reached 18%, then dried to safe storage moisture. Experiments show that the system could dry maize ear in short time, the piecewise drying process can reduce energy consumption and production costs 20% to 30%, and improve the average precipitation rates 4.2% compares with the traditional drying process. Meanwhile, the rate of seed crushing is decreased 1% to 1.5%.

The effects on property of Fe3Al-based alloy adding 1.0at.%Mn,5at.%Cr,0.5at.%V have been studied. Alloys were smelted in a vacuum arc furnace and heat treated in box furnace under atmosphere. The tensile property test and hardness measurement indicate that Cr and V both can improve the room temperature ductility of Fe3Al-based alloy effectively, the effect of micro V to the ductility is correspond to the effect of 5at.%Cr, the Fe3Al alloyed by V has higher tensile strength and yield strength, the effect of 1.0 at.%Mn on the property of alloy is not obvious. The effects of various elements on Fe3Al-based alloy ductility are analyzed according to the electronegativity different of between the three atoms and Fe/Al atoms. Microstructure analysis shows that the reason of V improving the strength is the effect on solution strengthening and the second phase strengthening.

Based on the mathematical model of non-linear rubber bearings under the condition of random excitation and time domain model of road roughness, the 11-dof vibrant model for vehicle was built with considering the non-linear rubber bearings. Then the influence of the rubber bearings on ride comfort was simulated under the condition on the B-class road profile by different speed as the random input. The result shows that the way of modeling the vibrant model is feasible, and the influence is not a simple monotone function, especially in the barycenter acceleration of vehicle body.

This paper uses existing self-awareness technology and power management strategy to propose a new strategy for nanosatellite power management. We dynamically manage the power through the awareness of the target applications’ running state. Based on applications’ performance requirements we use DVFS to optimize power management. Finally, our strategy had helped to improve the power utilization rate of nanosatellite systems with expected performance.

The pressure-sinkage characteristics and the shear-strength characteristics of lunar regolith are the important influence factors to the trafficability of lunar rover. The performance curves and parameters of JLU luanr soil simulant were obtained by pressure-sinkage tests and shear-strength tests in the ground gravity-environmental load (1g) and the lunar gravity-environmental load (1/6g). The results show that, for the pressure-sinkage characteristics, the compression-strength of the JLU-1 is strongest, followed by the JLU-3, and the JLU-2 is the weakest. In different load levels, the deformability index n increases as the bulk density increases. The kc increase as the state becoming more and more compact,The k of JLU-1 is the largest of all, followed by JLU-3 next, JLU-2 has the smallest.The load levels have no significant effect to the tendency of n, kc and k. For the shear-strength characteristics, the shear resistance of JLU-2 is the weakest. JLU-1 has the greatest cohesion c of the three lunar soil simulant, followed by JLU-3, the c of JLU-2 is the smallest.The c of the same lunar soil simulant in natural state is greater than it in soft state. Compared with JLU-1 and JLU-3, JLU-2 has the smallest internal friction angle .The influence of the load levels to the the cohesion c internal friction angel is not obvious. The  mesured in the lunar load is wider than it in the ground load. This study will supply fundamental reference and foundation on the research and optimization of the lunar rover traveling mechanism in the authentic lunar environment.

The paper analyzes the method of direct tension control, provides repaired method of closed loop speed for tension control of underfeed winder, and designs the systematic hardware figuration and software to effectively meet the demands of different volume control. Furthermore, the problems including pressure control of pressing roller, load distribution control of two-drum winder, tension control of paper, and dynamic compensation control were analyzed and solved through the design of hardware and software of S7-300 PLC.

In this paper, Mobile Agent (MA) and a number of intrusion detection system described. Considering the shortcoming of the current intrusion detection system, a new system called the intrusion detection system based on MA was described. Using the autonomy of MA, Intrusion Detection System based on MA avoids single-point failure, and robusts the system. As a result, the security of network has been increased.

The DTC for PMSM possesses many advantages: simple control configuration, lesser parameters dependence and fast dynamic response and is a good choice for the drive of EV. But the DTC suffers from high torque ripples. The switching table is used as the hysteresis control rule that determines the control performance. An improved switching table is proposed based on effects of voltage vectors on the drive. Simulation results show this switching table can suppress torque ripple compared to the conventional switching table.