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Altitudinal range is widely used as a proxy of habitat heterogeneity to explain broad-scale geographical patterns of species diversity. Though altitudinal range is a factors derived from altitudinal gradient, altitudinal range’s effects on species diversity on altitudinal gradient remain little known. Based on large scale information of plant species, climatic and geographical factors, we investigated the altitudinal patterns of plant species diversity in the East Himalaya regions, and the effects of altitudinal range on species diversity on altitudinal gradient. We constructed two coefficients, ARDMA (altitudinal range divided by median altitude) and SDDAR (species diversity divided by altitudinal range). We used Spearman’s rank correlation to examine the associations among all of factors. Our results showed that species diversity decreased as the increase of altitude, and significantly related to potential evaporation. No significant correlation was observed between altitudinal range and species diversity, whereas ARDMA significantly related to species diversity, suggesting that only when altitudinal gradient was controlled, were there significant correlations between altitudinal range and species diversity. SDDAR significantly and negatively related to median altitude. We concluded that energy availability significantly affected the altitudinal patterns of species diversity, and altitudinal gradient may shadow the effects of altitudinal range on species diversity.

The contact between substrate and micro-cantilever simplified as an ideal flat substrate contact with a micro-cantilever rough surface. A three-dimensional adhesive contact model was established on isotropic rough surfaces exhibiting fractal behavior, and the equivalent plastic strain was discussed using the finite element analysis. The maximum equivalent plastic strain and its depth were presented with the different paths of rough solid when loading. The result show that the equivalent plastic strain versus different depth which at different locations showed different laws, in the top area of the asperities versus different depth, the maximum equivalent plastic strain occurs in the subsurface range about 0.5μm from the surface or on the surface. In addition, with different deformation characteristics, the degree of the equivalent plastic strain was different.. The contact model between micro-cantilever rough surface and flat substrate will lay a foundation to further research on the substance of the process of friction and wear.

The vacuum of condenser is an important parameter in the operation of steam turbine, which has a great influence on the safe operation and regulation performance of the turbine. Since the influential factors of vacuum reduction of condenser are fuzzy and uncertain, the improved FAHP is used. By comparing every two of the influential factors, the fuzzy matrix is constructed. The weight index of influential factors of vacuum reduction of condenser in a certain power plant is calculated out quantitatively. The most important influential factor is found out. And there is a verification which exactly identifies the fault of the condenser by using a real instance.

Cultivating innovative talents is an important task of colleges and universities. It is the trend of higher education development and the need of social development. Experimental teaching is an important link to develop students practice ability as well as innovative ability. The open experimental teaching is an effective way to train innovative talents. The content, conduct, effect and significance of open experimental teaching were studied in fluid mechanics.

The analysis in this thesis carried out to describe the changes of economy based on input-output model can only be regarded as an approximate reflection, considering the complexity, variability and uncertainty of the economical society.

This paper took one 330MW unit boiler in one power plant as an example, then doing some research about the boiler system energy change through doing exergy analysis. After this, the exergy flow equation was established, the energy transfer, utilize and loss of the thermal power plant production was revealed, the exergy efficiency of the boiler was defined. So the paper can provide a basis for energy utilization of power plant.

In order to solve the problems about testing and analysis for the optimization problem of the mountain orchards transport aircraft operating parameters and structural parameters, we build a transport aircraft control test platform. According to actual needs, for complete the circuit design,select the appropriate frequency conversion motor, frequency converter, PLC, and other critical hardware.Using fuzzy PI controller, in the Step-7 authoring environment to compile, complete the PLC programming design; Complete interface design in the in Eviews editing software EV500.After constantly adjust, in conditions for a variety of conditions like stoping in an emergency, an emergency starter, speed transient change, instantaneous change of goods bias, cargo rolling random, the system can be stable operation, uniform speed, experimental platform vibration is very small, the vibration of the truck itself is also very small,which can meet the test requirements enoughly.

This paper analyzes the mechanism of process antenna effect in ultra deep submicron IC physical design and provides the antenna ratio calculation method. A new elimination method of process antenna effect combined with clock tree synthesis is proposed. The elimination method minimizes the impact to the clock latency and clock skew by setting up reasonable constraint for clock tree synthesize. Finally, the elimination method is used during place and route of the physical design of a reconfigurable video decoder chip, which is based on TSMC 65nm low power technology. The proposed method eliminates the process antenna effect of the design effectively, also minimizes the impact to clock tree and chip timing to the least.

In this paper, with the ANSYS, stress distribution and safety factor of crankshaft were analyzed by using 3D finite element method. The results show that the exposed destructive position is the transition circular bead location of the crank web and the crankpin. Maximum stress is 118 MPa. Safety factor is 2.72. Maximum deformation is 0.773 mm. Crankshaft satisfies the design requirement.

In this paper, with the ANSYS, stress distribution and safety factor of crankshaft were analyzed by using 3D finite element method. The results show that the exposed destructive position is the transition circular bead location of the crank web and the crankpin. Maximum stress is 121 MPa. Safety factor is 3.12. Maximum deformation is 0.0719 mm. Crankshaft satisfies the design requirement.

Sliding velocity has a direct impact on friction heat and contact situation. Frictional heating and associated temperature seriously affects the material chemical and physical - mechanical properties, and is one of the direct factors on the wear mechanism. To analyze the influence of the sliding speed on the maximum contact temperature, contact pressure, stress, etc, a 3D thermo-mechanical coupling model for the rough surface frictional sliding is established. The rough surface is characterized based on fractal theory. The model considers friction contact between an elastic flat plane and an elasto-plastic rough surface. Also, the model integrates the heat flux coupling between the sliding surfaces and allows the analysis of the effects of elastic-plastic deformation of rough body and the interplay among asperities. The numerical results from the analysis and simulation show that the maximum contact temperature increases with the increasing of the sliding velocity. But the maximum VonMises equivalent stress and the maximum contact pressure have few relationships with sliding speed. They may increase or reduce with the sliding velocity increasing. Some results are validated by research’s results available in the literature.