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Nassr1,a and Wael Khair-Eldeen2,b 1Department of Civil Engineering, Assiut University, Assiut, 71516, Egypt 2Department of Mechanical Engineering, Assiut University, Assiut, 71516, Egypt aamrnassr@aun.edu.eg, bwaelmk@ittu.org Keywords: anchors, concrete, damage, dynamics, impact, strain rate, waves.
The ultimate load at splitting failure of an anchorage is affected by several factors such as the material properties of the concrete (concrete compressive strength); the size of the activated fracture surface (distances to the edges of the member or spacing in anchor groups); and the geometrical parameters of the anchors (anchor diameter and/or its embedment depth) [1].
It was found that the variation of the concrete strengths affected the loading capacity of the anchors by a maximum of 25%.

Placement Optimization for Thermal Performance of Embedded Power Chip Microwave Modules Using BP-GA Sheng Zhanga Zhaohua Wub Hongyan Huangc Pin Chend Tangwen Bie School of Mechanical & Electrical Engineering, Guilin University of Electronic Technology, Guilin, China 541004 aguxing916@126.com, bemezdj@guet.edu.cn, chhywangyi@163.com Keywords: Thermal Analysis, BP Algorithm Network, Genetic Algorithm, Microwave Modules, Optimization Design.
Introduction Temperature is the key factors which affect the working reliability of electronic devices.
The embedded-chips of components are the main source of heat, the position of the chip directly affects the distribution of the temperature field, the unreasonable layout of naked chip will lead to high temperature gradient and temperature in the internal and external microwave modules, and then reduce the reliability and performance of the microwave modules, so in the stage of placement optimization design for thermal performance in embedded high power multichip modules, using computer to simulate the temperature after placement is very necessary.
ALL materials, packaging body sizes and corresponding material properties are shown in table 1.

In this paper, a stable and controllable mechanical device was designed and its reliability was tested and verified by theory design, underwater experiment and the finite element analysis.
And cracks would occur around the holes because of stress concentration phenomenon in the drilling process and there were inestimable factors affecting the piston cavity’s pressure ability.
The three-dimensional entity model with PVC materials properties was built in Pro/E software in the paper and the stress and strain of piston cavity could be analyzed [6,7] using powerful ANSYS finite element analysis function.

Fan1 1College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China, 210016 2College of Engineering, Nanjing Agricultural University, Nanjing, China, 210031 ashh@nuaa.edu.cn Keywords: Solid lubrication, Ti-6Al-4V, Grinding temperature, Microstructure Abstract.
The most influential factors affecting the grinding temperature were studied by conducting the experiments.
Microstructure of the ground surface layer.The microstructure of the ground surface layer is essential to the service property of the workpiece due to the distortion of crystal lattice during the plastic deformation of the surface layer under the grinding force.
The similitude of the microstructure of the surface layer with the mother material indicates that the lubricating property of the graphite and HBN are effective in reducing the frictional forces at the wheel-workpiece interface and the deformation of the surface layer of the workpiece.

As Rivin points out, in the mount stiffness, the great deviation between the engine weight, center of gravity inertial motion and position of the actual vehicle, their deviation will greatly affect the optimization results of engine mounting system, and lead to restricted its practical application.
Modal analysis of engine assembly The vibration characteristics of the mechanical system mainly depends on the system itself, the inertial, elastic and damping.
These properties of the actual structure is relatively complex, in order to carry out the calculation and analysis of vibration characteristics of the mathematical tools for their use, the actual system need to be simplified to some extent: ignoring secondary factors, properties of simplifying its quality, stiffness, damping and other parameters and distribution, established can reflect dynamic characteristics the actual system also has the possibility of dynamic model of the.
Mechanical model of ideal therefore simplified from the actual machinery to reflect the physical process, it is necessary to determine the four elements.
An Investigation of Fatigue Failures of Turbine Blades in a Gas Turbine Engine by Mechanical Analysis.

Wavelet analysis has good time-frequency localization properties and adaptive capacity of the signal, so it is able to analyze all sorts of time-varying signals effectively.
That can simulate a mechanical vibration environment.
Wavelet function with different parameters has different time-frequency properties.
In turn, the smaller tightening torques, the more non-linear factors in relative displacement among the fittings, which results in the energy of the bandwidth increases and the separation collision of macro-scale happens.
Wang: Mechanical Science and Technology, Vol. 25 (2006) No. 1, pp. 102-106.

Engineering geological properties and the process of establishing geological model of open -pit mine in the north of Axi gold deposits in Xinjiang were introduced .It simulated the laws of deformation, stress and plastic zone of the top and base of wall rocks of underground mining in two conditions.
The resources above 1450m level have finished and under 1450m level have turned to underearth mining.Open- pit mine in the north of Axi gold deposits has been planned as a natural tailings reservoir after it closed in order to solve stacking problems of mineral slag and relieve the stress of peripheral tailings reservoir.Howerer,whether tailings surcharge load would affect underneath mining then bring hidden danger becomes the most concerned point.
There are 6472 joints and 19538 units.According to material properties and order of excavating layer as well as tailings surcharge load,the model was classified as 13 groups.See Figure4: displacement constraints of right and left boundary in X direction, displacement constraints of base line in X,Y direction, free constraint of the surface.We have chosen four monitoring points which could record variation process about stress and displacement of monitoring points with the change of time stepping in different conditions(see Fig.3 ).
Conclusions In the north open-pit of Axi gold deposits in Xinjiang, the impact that tailings surcharge load on overlying orebody mining depended on many factors such as mining methods, occurrence state of orebody, the material and filling state of filling mass, the order of tailings surcharge load and so on.
The Mechanical Basis of Mine Filling[M].

MICROSTRUCTURE EVOLUTION AND MICROSTRUCTURE - PROPERTY RELATIONSHIPS IN FRICTION STIR PROCESSING OF NiAl BRONZE T.R.
However, the direct measurement of stir zone temperatures, strains, strain rates and cooling rates is difficult due to steep gradients and transients in these quantities, and this is an impediment in the assessment of FSP-induced microstructures and properties.
Factors that influence the distribution of strength and ductility in the stir zone appear to include the mixture of microstructure constituents and gradients in microstructure due to gradients in processing conditions.
The severe, but localized, plastic deformation results in formation of a stir zone (SZ) while adjacent regions that experience only moderate straining comprise the thermomechanically affected zone (TMAZ).
Benefits of FSP in cast metals include elimination of porosity and local conversion of cast microstructures to a wrought condition, with enhanced surface properties.

The properties of the P-type silicon wafer and Pyrex glass are given in Table 2.
Table 2: Mechanical and Thermal Properties of Work Material Material Hardness [GPa] Density [g*cm3] Thermal conductivity [W / (m × K) ] Melting temperature [oC] P-type silicon 12 2.33 148 1414 Pyrex glass 418 2.23 1.1 821 The experiments have been carried out according to the 3-level Box-Behnken design based on response surface methodology which provides 17 runs of experiment.
Surface roughness affects corrosion, fatigue life, friction and wear and tear of parts.
High temperature is main factor for the modified high CO2 laser absorption of silicon wafer.
Rizman: Numerical and Experimental Analysis of Activated Carbon Filter on the Mechanical Properties of Wood Composites.

For natural gas well in sour gas reservoirs, very serious corrosion in the gas well string is an important factor of gas production system life.
Introduction Some oil and gas wells have adverse working environments, so their service lives and properties will seriously affect the exploration and development and the operating benefits of oil and gas fields.
Corrosion due to water and other factors[1,4,5,6,7].
Despite the fact that H2S/CO2 is the most severe corrosion factor for the facilities of sour oil and gas fields (especially hydrogen sulfide, which may not only generate abrupt sulfide stress cracking of metal to cause great economic loss but also have toxicity that may threaten personal safety), the corrosion action of mineralized water cannot be underestimated.
When high sulfide-resistant and common tubings and the addition of corrosion inhibitor that was appropriate for fluid properties were adopted, the gas wells that had produced for long time could still maintain normal production.