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Firstly, the characteristics of regular Zigbee localization algorithms-the received signal strength indicator algorithm (RSSI) and the weighted centroid localization algorithm are introduced. Then, the factors of the errors existing in the aforementioned algorithms are analyzed. Based on these above, the improved RSSI algorithm-correction geometric measurement based on weighted is proposed. Finally, utilizing this algorithm to design and implement the localization nodes, which have the CC2431 wireless microcontroller on them. The simulation and experimental results show that the accuracy of this localization algorithm improved about 2%, comparing with the regular algorithms.

Fully developed turbulence single phase convection heat transfer of water in pipes filled with sintered porous metal inner rings or solid inner rings was investigated numerically respectively. Numerical calculations were conducted with the Fluent 6.3 code, using the SST k-ω turbulence model. Comparing to solid-ring turbulator pipes, porous-ring turbulator pipes have better comprehensive heat transfer effect. The maximum PEC for porous-ring turbulator pipes is 4.4 and the PEC of solid-ring turbulator pipes is less than 1. It was also analyzed effect of geometric structures on porous-ring turbulator pipe performance. f/f0 for porous-ring turbulator pipes increases with the increasing of Re while Nu/Nu0 decreases with the increasing of Re ,and PEC decreases with the increasing of Re. With the same Re, if the width of the porous ring is equal to the width of groove, f/f0, Nu/Nu0 increases and PEC decreases with the increasing height of porous ring. When the height of porous ring is constant, the f/f0, Nu/Nu0 and PEC decreases with the increasing height of porous ring under the same Re.

Tennis has gradually become a very important leisure and entertainment project, and it has been popular among the extensive tennis fans. People pay close attention to the tennis materials and keep doing research all the way. Since the beginning of tennis, the tennis materials has been changed constantly, which ranges from the initial wood to the gradually emerging new macromolecule polymer material. The new macromolecule polymer material is of high intensity, toughness and antiknock, which is rather applicable to the tennis design technology. However, so far due to that the macromolecule polymer materials cost is higher, its promotion is limited in certain scope, and mainly be selected by the professional competition tennis players. And most of the tennis fans generally are in favor of the traditional tennis racket. This paper conducts comparing on the traditional material of tennis racket with the macromolecule polymer material of tennis racket, and makes it stand out so as to display the wide prospect of the application of the new macromolecule polymer material in the tennis design technology.

In order to obtain the concentration, temperature and size variations of a bicomponent moving droplet during evaporation process, a mathematic based on multicomponent droplet evaporation model and droplet motion equation was developed to simulate the evaporation characteristic of a binary decane-ethanol droplet at high temperature nitrogen environment. By numerical calculations, the time evolution of internal concentration distribution within droplet was obtained, and the variations of droplet temperature and dimensionless size were analyzed. The numerical results show that: the droplet temperature variation includes transient heating and equilibrium evaporation at atmospheric pressure; while at high pressure environment, the droplet temperature increases gradually till reaches to ambient temperature. The variations of dimensionless droplet size are deviated from the d2 law due to the concentration variation during evaporation.

In order to achieve high efficiency of new fuel engine, a mathematical model based on mass, momentum and energy equations was developed to describe the motion and evaporation characteristics of a single ethanol droplet in high temperature nitrogen environment. By comparing the numerical results with experimental data, the validity of model was confirmed. The relationships of droplet temperature, velocity, size with time and movement distance under different ambient pressures were analyzed. The calculated results indicate that with a higher ambient pressure, the droplet temperature is higher, the droplet velocity declines faster, the movement distance is shorter; the evaporation rate is slower, and the droplet life is longer. Within the distance where the droplet velocity continuous variation, the droplet temperature rises gradually, the droplet size expands slightly, and with the increase of ambient pressure, the droplet expansion is more significant.

Difference of trolley traction distribution and slip angle of tire wheels may cause extra horizontal force to legs of tire gantry crane. The case and cause were studied to estimate the force for the crane design, control, and operation. And that was compared with one specialized in the design rules of rail gantry crane. It can be found that under proper control and operation condition the later can also be applied to the tire gantry crane.

This paper, based on the origin of Karst Area landslide and the geographical conditions of Guizhou, studies the application of WSN technology on monitoring and forecast landslide and other geological disasters in Karst, and then put forward a landslide monitoring plan. We study the data acquisition layer node topology, and construct WSN monitoring system and test it under the stimulated environment. The result has shown that, the constructed monitoring system can meet the need of real time monitoring of landslide stability in Karst Area.

Precise navigation and localization of the autonomous rover in unknown environment is important both for its own safety as well as for its ability to accomplish engineering and scientific objectives. In order to navigation autonomously the rover should have the ability of apperceiving the environment and avoiding the obstacles. Laser range finder is used to rebuild the environment and fuzzy reasoning method is used to avoid obstacles. Most importantly the rover process the sensor data to produce an estimate of its position while concurrently building a map of the environment. The improved filter algorithm is proposed to make the method feasible.

Diatomite/polyacrylic acid composite was synthesized by using inverse suspending polymerization method under different diatomite content, dispersant content and neutralization degree with orthogonal experiments. The surface morphology, structure and humidity controlling properties of composite were observed and determined. The results show that diatomite/polyacrylic acid composite is in a block like structure with different size. During the polymerization process, acrylate monomer is grafted with hydroxyl on the surface of diatomite and then inserted successfully into the void of diatomite. The impact of three factors on the humidity controlling behavior of composites increases by the order of dispersant content, neutralization degree and diatomite content. The optimum preparation parameters are diatomite content of 40%, dispersant content of 15%, neutralization degree of 90%.