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A number of cavities appeared behind lining after completion of the Longmen tunnel which will be studied in this paper, they lead to initial lining crack and leakage and have affected the normal operation of the tunnel.
The tunnel gradually appeared such diseases as the lining crack, leakage and so on, and which had affected the normal operation of the tunnel.
Physical and mechanical parameters of materials are shown in Table 1.
This shows that the above reinforced plans can reduce the differences of peak acceleration response, and increase the structure integrity of seismic response of tunnel lining, and it improved the deformation property and seismic characteristics of tunnel lining
That means that the restriction effect of surrounding rock is main factor of the seismic response characteristics of tunnel lining structure

The novelty of the developed device is that the properties of the damper are adjustable based on the structural requirements.
The equation of motion (1) is solved and modal properties are estimated to adjust the modal mass of the structures.
Nigdeli, Mass ratio factor for optimum tuned mass damper strategies.
International Journal of Mechanical Sciences, 71 (2013) 68–84
Transactions of the American Society of Mechanical Engineers, 50 (1928) 9–22

Therefore, any attempt to control the product properties must be done through the understanding of the raw material properties and by the control of the processing parameters [3].
These failures affect the quality of the ceramic part, generating economic damages to the ceramic industries [5].
From this curve, it is possible to select the ceramic material part, that is able to be subjected to the temperature variations of the firing step and present the desired properties in the finished part.
It is dependent on the surface geometry, the nature of the flow (forced or natural) and the properties of the fluid (density, viscosity, thermal conductivity and specific heat).
Other factors should be taken into account when choosing the type of thermal insulation, such as the useful life and the average cost of maintenance.

It should be considered simultaneously to material removal ratio models of part and media, which can directly affect finishing capacity and economy.
Mutual influence between indices is also studied to decide how to affect working performance.
Wang: China Mechanical Engineering, Vol. 10 (1999), pp. 397
Wang: China Mechanical Engineering, Vol. 12 (2001), pp. 300
Li: Mechanical Engineering & Automation, Vol. 6 (2009), pp. 41

Compare to traditional power supply of spot welding ,inverting spot welding has a lot of advantages :with small volume of transformer ,light ,integration of welding clamp ,transformer and secondary rectifier , it is used into the spot welding robot ,the drive power and assembly weight of the spot welding robot[3] ;the inverting frequency of inverting spot welding power supply could be tens thousands of Hz ,even hundreds of Hz ,so the speed of response and ability to control and discompose of the whole feedback control system is better than traditional frequency spot welding power supply ,and easy to realize automation and intelligent control ;according to frequency spot welding power supply ,inverting spot welding power supply can save 25% - 30% energy with high power factor and good energy-efficient economy ;in welding area ,inverting spot welding has the advantage of large range of current of forming stable nugget ,long life of electrode ,small electromagnetic elects ,no alternating
“skin” affect ,and big ability of spot welding dissimilar metal .Summing up the appeal ,inverting spot welding power supply is the best spot welding power supply with every technical specifications[4，5].
Optimize Circuit Parameters WITH ACA The Process of electric resistance spot welding is very complicated :the influence of technological parameter on quality of welding is nonlinear process ,and each technological parameter which works to each other, interferes each other ,affect the quality and the property of weldment .So it’s impossible to build accurate model in theory ,and determine optimal program with mathematical programming method.
References [1] XiHua Zhao .Pressure Welding [M] .Being Jing :Mechanical Industry Press ,1995 [2] Zhengxing Zhu ,Xiangming Yan ,Min Wang .Resistance Welding Technology [M] .Bei Jing : Mechanical Industry Press ,2002 :51-55 [3] Zhicheng Deng ,Jun Lin ,Juntao Wang .The Development of Spot Welding Power [J] .Shanxi Science and Technology ,2007(1) :132-134 [4] Ping Fang .A Review of the Application of Invert Technology to the Resistance Spot Welding [J] .Journal of Nanchang Institute of Aeronautical Technology ,2001 ,(3) :16-19 [5] Minyu Zhao ,The Research of Medium Frequency Inverter Resistance Spot Welding Control System Based on DSP [D] .Shenyang University of Technology ,2008 :14-20 [6] Xigong Li ,Ludong Yang ,Liang Zhang .20kHz High Frequency Inverter Power Supply for Resistance Welding [J] .Transactions of the China Welding Institution ,2006(2) :105-107 [7] EIBann，Mahmoud ,Filevoimitar ,Intelligent constant current control for resistance spot welding[J] .IEEE Intemational Conference

Their excellent mechanical properties sign a extensive perspective of application.
About Al80Ni10Zr3Cu5Y2 alloy, the synthetical effect of Cu and Zr is an important factor of forming amorphous alloys.
The crystallization temperature of amorphous alloys is deeply affected by the liquid atomic clusters.

Rahnejat 3,b 1 National Centre for Advanced Tribology (nCATS), Faculty of Engineering and the Environment, University of Southampton, Southampton, UK 2 Faculty of Engineering and the Environment, University of Southampton Malaysia Campus, Nusajaya, Malaysia 3 Wolfson School of Mechanical & Manufacturing Engineering, Loughborough University, Loughborough, UK a w.chong@soton.ac.uk, b h.rahnejat@lboro.ac.uk Keywords: Modified Eyring thermal activation “cage” model, molecular solvation, friction force microscopy, potential energy barrier and nanoscale friction Abstract.
During the experiment, it is necessary to maintain a meniscus forming along the edges of the tip holder (see figure 1), which also ensures that the relatively large negative meniscus pressures between the fluid and tip holder do not affect the friction measurements.
The calibration factor for the silicon nitride AFM tip on a silicon calibration sample [15, 16] is defined as: α=Ff(volts)/Load(nN)0.19 (1) Mathematical Approach Friction generated along the assumed opposing molecularly smooth asperity summits, separated by ultra-thin adsorbed films, follows the non-Newtonian shear as a result of chemical reactions based on thermal activation.
The shear properties of langmuir-blodgett layers.

Introduction Low temperature surface modification by mechanical processing such as burnishing or friction stir processing becomes to be widely used for many metallic materials now.
It is reasonable to reduce the energy input into the process since it may affect the final structure of the processed metal or weld.
The distribution of slip bands (SB) on these faces is governed by the Schmid factor values for the slip systems and loading forces which include both compression and friction forces.
Rigney, The effects of sliding velocity and sliding time on nanocrystalline tribolayer development and properties in copper, Wear 267 (2009) 562–567

Among the potential TL dosimeters, lithium fluoride is one of the most popular dosimeters and is commercially available due to its human tissue equivalence (Z eff = 8.04), which is an important factor for personal dosimetry, simple glow curve, high sensitivity and limited fading over a certain period.
In this work the preliminary study of TL properties of Al2O3:C in powder form were investigated in term of glow curve characteristics, TL-dose response dependence and sensitivity.
X- Ray Diffraction Analysis (XRD) XRD analysis was carried out using Siemens Diffractometer D5000 system at Faculty of Mechanical, Universiti Teknologi Malaysia.
The sample was covered by a black paper to avoid exposure from fluorescent light which might affect the TL response of the sample.

However, domestic and foreign scholars mostly focused on influence factor of gas diffusion, such as terrain, surrounding environment and leak location.
(4) Where cp is the specific heat capacity, T is the temperature, K is the fluid heat transfer coefficient, sT is the internal heat source of the fluid and the part of the conversion from fluid’s mechanical energy to heat energy due to viscous effects, sometimes sT is called viscous dissipation for short
As can be seen from the figure, air flow affects the windward side of the storage tank, which is blocked by the tank in the windward region, causing the formation of larger air flow.
Since the physical properties of liquid ammonia is very special, its storage condition is high pressure or low temperature, this study set storage conditions for the tank pressure is 882KPa (293K), the pressure inside the tank is large, and the tank rupture suddenly, which makes the tank pressure drop, liquid ammonia vaporize rapidly in the tank for ammonia gas, diffusion to the atmosphere under the action of wind, the influence area of diffusion will expand with the extension of time.