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This paper proposes a drawing simulating method by means of drawing out coordinated system and relevant object for every link of the articulated industrial robot in UG system. Because the structural and kinematical parameters are defined with variable element in UG system, the conFiguration of terminal link and other link are all simulated. It is appearance that the drawing course by this way is simple and the drawing result of the articulated industrial robot is visual, believable and reliable.

In order to improve energy utilization rate of biogas engine-driven heat pump (BEHP) systems for wastewater treatment plant, the exergy analysis is applied in this paper. The paper concludes the exergy losses and exergy efficiency of each equipment, and reveals the weak link of energy transformation of the whole system. According to the calculation of one example, the location of maximum exergy loss is the biogas engine-driven, while the location of minimum exergy efficiency is the compressor, which provides powerful theoretic references to improve and optimize BEHP systems for wastewater treatment plant.

PA6 composites filled with nano-SiO2were synthesized. The aim of the research article is to study the mechanical and friction and wear behaviour of nano-SiO2reinforced PA6 composites. The worn surface of the composite was examined by scanning electron microscopy. The results showed that the addition of nano-SiO2can effectively improve the mechancial and tribological properties of the PA6 composites.

The effects of CF content on flexural and tribological properties of the composites were investigated. The worn surface morphologies of neat PTFE and its composites were examined by scanning electron microscopy (SEM) and the wear mechanisms were discussed. The presence of CF particles dispersed in the PTFE continuous phase exhibited superior tribological characteristics to unfilled PTFE.

The present study establishes the relationships between the cutting conditions (cutting speed and feed rate) on trbological properties. Three types of PEEK composites such as unreinforced PEEK, reinforced PEEK with 20% of carbon fibres and 20% of glass fibres were used for the tribological tests. The parametric analysis reveals that, wear increases with increase in feed rate and cutting velocity while the friction coefficient decreases for all the materials tested. The investigation illustrates that the addition of reinforcements to PEEK improve the tribological properties relation with the cutting conditions.

The mechanical and tribological behaviors of the carbon/carbon (C/C) composites were evaluated by three-point bending and sliding wear tests. The effect of carbon fiber content on their mechanical behavior was also investigated. To produce the C/C composites, the precursor was introduced to the preforms by impregnating with phenolic solution. The C/C preforms were densified by thermal gradient chemical vapor infiltration. Results indicated that, the C/C composites show excellent mechanical and tribological properties. A kind of high performance brake materials was obtained.

Paper discusses that water content of emulsion has effects on the surface quality of cold-rolled aluminum alloy 5052 and higher concentration of emulsion gave thicker lubrication film and better surface quality of aluminum strip. When the speed of rolling reaching a critical speed, thickness of emulsion film will decrease with time. Film forming of emulsion shows that when rolling speed is low, properties of emulsion is similar to that of oil, while when speed reaching a critical value, mechanism of lubrication in rolling work zone will change from plate-out model suitable for low rolling speed to starvation model suitable for high rolling speed .This paper also discusses friction model for cold-rolling, and explains that the contact length of work zone and strip and forward slip get greater with rolling reduction increasing , which easily result in lubrication failure in the work zone.

With the speeding urbanization process in China, the amount of floating population increases at an unprecedented speed. How to solve the housing security issue now becomes a key indicator for social stability. In this paper, a new low-income housing requirement prediction method is proposed based on stepped leveling of floating population and related evaluation index predictions. Using Logistic retardant population growth model and Todaro method, floating population in the next 5 years is predicted. Then the population is divided into stepped levels to predict housing requirement. Based on the prediction of commercial house price, the method of predicting low-income house demand for different levels in urban areas is given. To demonstrate the proposed model and method, Shanghai Statistical data over the years are used and analyzed.

At annealing temperature, Al-Mg alloys have grain boundary and surface magnesium segregation and their strength are also impossibly enhanced by heat treatment. Friction and wear properties of cold-rolled 5052 aluminum alloy annealed at different temperature were studied in this paper. X-ray diffract analysis(XRD) indicates that metallurgical phase has no obvious transformation with different annealing temperature. Auger electron (AE) fines that magnesium segregation and oxide layer thickness of surface are different along the plate thickness direction at different annealing temperatures. Results show that the higher oxide layer of the surface, the smaller wear can be got. Friction and wear testing shows that 5052 aluminum alloy annealed at different temperatures almost have the same coefficient of friction under the same experimental condition , but the coefficient friction of the same sample will increase while temperature rises.

BaTiO3 powders modified with Sm, La, Cu, Al, Zn were prepared by solid doping and gaseous penetration method and their components, structure, superficies and electric properties were characterized. The results show that the resistivity of the modified powders is decreased after both solid doping and gaseous penetration, and it is more obviously after gaseous penetration. Among all the metals being discussed, Sm has the most significant influence on decreasing the resistivity of modified powders. The room temperature resistivity of Sm-penetrated BaTiO3 powders is the lowest, which decreases from 8.3×1010Ω•m (pure BaTiO3 powders) to 1.65×105Ω•m. SEM investigation illustrates that the powders are in uniform grain size. No apparent pores and small grains are found. XRD analysis indicates that the doping process only leads to the changes of the peak width and intensity without new phases appearing, but characteristic peaks of Sm2TiO5, SmTiO3, and Ba10.37Sm17.08Ti36O108 can be detected after gaseous penetrated, which leads to the decrease of the resistivity of modified BaTiO3 powders.