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The results show that: there are great differences between the resonance frequencies of two shells but the linear harmonic response properties are basically the same; the dynamic characteristics of these two shells are greatly different under harmonic loads or seismic loads, and the dynamics characteristics are greatly influenced by the viscous properties of the material itself.
Meanwhile, in high temperature or explosive environment, and with the impact load, the viscosity of steel material is enhanced highly and plays a dominating factor of the whole mechanical properties of the structures.
To investigate how the material viscosity affects the vibration characteristics of long-span space structure under harmonic loads or seismic loads comparative analyses of two aluminum alloy single-layer spherical shells with the same span, same rise-span ratios and same bars, but one is elastic and the other is visco-elastic, are carried out.
Obviously, the vibration characteristics of shells are apparently affected by the viscosity of material.
Acknowledgment This work has been supported by Guangdong Province Science and Technology Plan Project (2010B010800004; 2011A080802010) and the Opening Fund of Laboratory for Mechanical Behaviors and Design of Materials, Chinese Academy of Sciences (LMBD-2011-2).

At present, the builder decides for the final selection of the design (material) solution of a passive house based on mechanical properties of materials, thermal technical properties of materials and cost of materials.
Finally, it often puts great emphasis on energy carriers ensuring the operation of building and affect the need for primary (renewable and non-renewable) energy.
Thermal and technical evaluation The difference of designed thickness of thermal insulation is based on the different properties of the thermal conductivity λ [W / (m·K)].
Table 6: Comparison of properties of variants no. 1 and no. 2 [9] Variant no. 1 Variant no. 2 Used thermal insulation foam glass (530 mm) XPS (220 mm) Temperature conductivity factor λu [W / (m·K) 0.082 0.034 Specific heat capacity (J·kg-1·K-1) 750 1450 Compressive stress at 10% of relative deformation 570 500 Density (kg·m-3) 150 38 Flammability class A1 E Recyclability YES YES Emissions of CO2 / SO2 (kg / kg) 0.431 / 0.00193 4.2 / 0.0155 Conclusion Not only the choice of structural solution is important in the design of a passive house.
Windows in buildings - diagnostics of selected properties after time of using.

Introduction The length to diameter ratio greater than 20 to 25 of the shaft are usually called slender shaft[1,6,10], screw and feed rod of lathe, for example, witch frequently used in machinery industry, prone to bend and vibrate affected by the factors such as cutting forces, clamp forces, cutting temperature, self weight.etc.
By this way, if the center pushes too tight, the shaft will be bent, the thermal extension will be hindered, thereby lead to the bending deformation affected by axisymmetric compression.
Static Analysis After building the 3D model, define the material properties, position constraint by restricting 6 degrees of freedom of X,Y,Z rotation and axial movingon on the Φ12mm cylindrical surface, restricting 4 degrees of freedom of X,Y rotation and axial moving on the surface of the other end.
Mechanical Engineering & Automation, (2005) No.3, p.97-98 [8] Q.L.
Pro/Engineer Wildfire 4.0/5.0 mechanical structure Analysis in Practice (China Machine Press, China 2011).

The requirements of machining accuracy and efficiency on super-alloy are increasingly high with the development of mechanical industry [2].
According to the mechanical properties and characteristics in the cutting process of tool material, tool geometric parameters are selected as follows: rake angle is 5°, back angle is 5° and tool edge radius is 0.01mm [6].
Thus the effect of single factor change on cutting force and temperature is analyzed through comparison and observation.
Analysis of Simulation Results The Affect Cutting Parameters Makes on the Cutting Temperature.
Cutting depth is the most influential factor of cutting force, and cutting speed is more influential than feed rate on cutting force.

Owing to small VGE thickness high heating rates of workpieces (up to 100 deg/s) allow avoiding grain growth and associated deterioration of material’s properties [2].
It is known that favorable corrosion properties of steels can be due to compound layers [9].
In this article, we study the effect of the anode nitriding on the corrosion properties of medium carbon steels.
The additional oxidation of sample surface results in the increase in the oxide layer thickness and enhancement of its protective properties.
The protective properties of the coatings are stored for 1–2 hours.

In spite of these benefits, TiNi alloy cannot be machined by traditional machining methods such as milling, drilling and lathe due to high hardness property.
Moreover, there are reported that these machining heat and internal stress affect SME badly.
To select the suitable EP condition, experiment was conducted with duty factor 0.5, IEG 1mm, and current density 5 A/cm2.
Above mentioned duty factor is on/off time ratio in pulse current and IEG is a gap between anode and cathode.
Also, IEG, which is one of the most important machining factors, is established 1mm through initial experiment.

Some of these cracks affect the strength and consequently the safety of the dam.
T B b τ ωτ ε = + + (1) Where B is the amplitude of atmospheric temperature, B=20.0°C; ω is the circle frequency, ω=π/12; τ is time, month; ε0 is the phase angle, ε0=-6.5 months; b0 is the compensation factor of the atmospheric temperature, b0=2.0°C.
d f y ε γ = − − (5) Where T(y,τ) is the water temperature; y is the water depth, m; τ is the time; Tm(y) is the average temperature when water depth is y; A(y) is amplitude of temperature when water depth is y; other constants as show as follows: a=5.67, b=11.1, A0=13.4, β=0.013, α= -0.04, d=2.15, f=1.30, γ=0.085, τ0=6.5.Assuming constant and homogeneous thermal properties, the two dimensional heat transfer problem is governed by the differential equation 2 2 2 2 / / / .
Mechanical parameters of concrete dams are listed in Table 2.
It is now accepted that concrete deteriorates with time, not so much as a result of any lack of strength, but usually as a result of an inadequacy in one of its other properties.

The choice of the levels of reliability for a particular structure should take into account of several relevant factors including aspects of design working life, durability and quality assurance.
The approach of structural reliability is based on the semi-probabilistic method: limit-state performance design and partial factors method.
Summer storm on 23rd of August affected the northern part of the Ljubljana basin, Styria and some parts in east Slovenia.
We were not successful at obtaining information form the insurance companies, since they required written authorization letters form the property owners.
After taking into account the key factors – the characteristics of the atmosphere, facility location, terrain, height of buildings, etc. – the reference wind pressure as calculation load on structure can be calculated.

Example of pressure changes caused by implosion on the surface of a pressure pickup [2] The role of stresses in the process of hydrogen absorption and diffusion in metals and the influence of adsorbed hydrogen on mechanical properties of metals has been discussed in many publications [3-12].
The method used allows to observe that when a material is affected by cavitation, the states of stress vary and depend on depth.
Numerical models indicate that essentially changed properties can be found in an area of extreme parts of microvolumes affected by a microjet or shock waves generated by cavitation.
Migration of positive charges affected by implosion of a cavitation bubble [20] Fig. 9.
At the macroscopic level the deciding factor is a change in hydrogen concentration close to the crack bottom [24].

Applied test load has been found to be the most significant factor affecting the wear rate [22].
Previous studies focused mainly on increasing the tensile and wear properties of the FGM outer zone.
Evaluation of Wear Properties.
Interaction of Parameters Affecting Wear.
Varol, “Microstructural characterization and mechanical properties of functionally graded Al2024/SiC composites prepared by powder metallurgy techniques,” Trans.