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Box 2713, Doha, Qatar 1elsadigms@qu.edu.qa 2sebaey@hotmail.com Keywords: Glass fiber; Natural cotton fiber; Mechanical testing; quasi-static crushing; hybrid.
Natural fibers reinforced composites combine acceptable mechanical properties with a low density [5].
In an earlier study, Mahdi et al. [16, 17] studied, experimentally and numerically, different factors affecting the crushing behavior of natural UD cotton/epoxy tubes.
Fuselage-shape tubes, with two geometrical properties, are being used for its important application in aeronautics.
The stacking sequence of the sub-floor geometry highly affected the crashworthiness properties of the system.

The development of cutting material focused mainly on increasing the following properties: resistant to wear, resistant to high temperatures, strength, resistant to thermal shock, and hardness.
The development and application of new progressive materials is mainly affected by: their technological processing, demands on reliability, on longer service lives, and on reducing the weight of structures.
Several factors shall be analyzed for selecting material, including standards, codes and specifications, providing these exist for the given product lines.
The economy is an important factor in all proposal situations - selecting the right material with respect to service life, production and operation costs.
Table 1 Basic material attributes Physical properties Mechanical properties Corrosion properties Specific weight Melting temperature Heat expansion Conductivity Ferromagnetism Tensile stress Impact resistance Fatigue limit Creep limit Ductility Hardness Fracture toughness General corrosion Pitting corrosion Corrosion under stress Erosion Cavitation Oxidation Experiments and Results This paper concerns with the evaluation of the machined surface precision of holes.

However, mechanical properties of both the polymeric matrix component and fibrous reinforcement degrade after prolonged exposure to environmental factors such as heat, stress, moisture, corrosive fluids and ultraviolet rays during their service time.
Similarly, a lot of research work is available related to the effect of stitching on mechanical properties of composite materials.
Three important factors were considered for establishing the model [11]
Study on Mechanical Properties and Structure Design of Stitched Laminates, Dissertation for PhD degree Beihang University, 2004
Study on The Basic Mechanical Properties and Impact Damage Resistance Properties of Composite Laminates.

These transformations can be related to intrinsic characteristics of the materials and/or to exogenous factors and have visual manifestations that are the basis for its surveying and typology [1][2][4].
They can also affect recent constructions [4].
Underground Metro stations constitute particularly interesting research places for the study of natural stone changes over time since the influence of one of the main factors usually considered (exposition conditions) is minimized.
There are occurrences of surface irregularities in biotite-rich coarse-grained porphyritic granitic rocks applied in pavements (Fig. 3) that seem to specially affect yellowish slabs (yellowish discolouration in these rocks indicates weathering inherited from the quarry that affect physical properties of stones, causing, among other effects, physical weakening and increased porosity).
Fig. 6: Irregularities affecting dark greyish limestone applied in steps risers at the Oriente station (inaugurated in 1998, [7][8]).

Introduction Diamond was one of the ideal materials which were suitable for industrial applications because of its unique combination of excellent physical properties, such as high hardness, good thermal conductivity, outstanding wear and chemical resistance.
Concerning the applications, where low friction coefficient and great surface morphology were demanded, various techniques for depositing high quality diamond films of well defined material properties were pursued by numerous research groups.
In addition, the material properties of filament, cemented carbides substrate and workbench under the working condition have been shown in Table1 respectively.
Based on the AUX12 method for radiation, SHELL57 element should be specified on radiating surfaces to calculate the form factors of the radiating system.
The arrangement in the HFCVD reactor was the key factor influencing the growth rate and quality of diamond films.

This induced current and its skin depth depend upon the material properties.
Thus discharge energy in electromagnetic welds and in turn velocity of impact is the deciding factor for occurrence of wave at the weld interface.
This compression of grains improves the mechanical properties of weld interface.
There is absence of fusion and heat affected zone in EM weld.
Compression of grains enhances mechanical properties of EM welds.

Discrete Element Analysis of Friction Coefficient on Granular Accumulation Qinliang Li1,a, Bin Zhao2,b, Bo Wang1, Bangchun Wen1 1 School of Mechanical Engineering and Automation, Northeastern University, Shenyang, China 2 School of Mechanical & Electrical Engineering, Henan University of Technology, Zhengzhou, China aliqinliang@vip.qq.com, bzhaobin978@163.com Keywords: friction coefficient, granular accumulation, angle of repose, DEM Abstract.
For instance, angle of repose affects the upgrading angle of conveyor in the mine production system, which results in large arrangement area, big project and long structure.
This paper aims to reveal basic characteristics and laws of mechanical properties using discrete element method, providing a basis for the selection of friction coefficient in future simulation work.
The granular surface roughness directly affects macroscopic accumulation characteristic of the heap.
Angle of repose varying with friction coefficient between particles µs,pp and µr,pp are both important factors which influence angle of repose.

The depth of cut has more important effect on grinding temperature than cutting speed and feeding speed in three factors of grinding [1].
The metal material with high temperature is affect by extrusion and friction of grinding wheel, which leads to extremely serious flow trace emerged on the surface.
The grinding cracks can be avoided by selecting the optimization parameters such as grinding depth, thus the processing efficiency will be greatly improved and the surface quality of workpiece and the using properties will be guaranteed.
Research on the Grinding Force Based on the Probability Statistics [J].China Mechanical Engineering, 2007, 18(20): 2399-2402
Study on Grinding Temperature and Surface Burn out in High Efficiency Deep Grinding[J], China Mechanical Engineering,2004, 15(22): 2048-2051

Shrinkage and creep are the inherent properties of concrete bridge.
Introduction Shrinkage and creep are the inherent properties of concrete bridge.
Because a lot of factors affected shrinkage and creep are various related to time and environment factors, the internal force and long-term deformation of concrete bridge are obviously uncertain.
The mechanical performance analysis of these predicting models are all based on determination factors, which induces much deviation between calculation and real structure.
According to the uncertainty analysis for influence factors of ACI 2009 and CEB-FIP 90 model, In Hwan Yang determine the value of uncertainty parameters in shrinkage and creep model, material properties and environment variety [1].

Weldments after FSW thus result in less distortion compared to that after conventional fusion welding, however distinct microstructures are formed in the Nugget (stir zone), TMAZ (thermo-mechanically affected zone) and HAZ (heat-affected zone), which influences mechanical properties and in most cases deteriorates the fatigue performance of FSW joints.
Mechanical properties of the FSW joint and the BM are shown in Table 2 [12].
Table 2 Mechanical properties of base material (BM) and FSW material [12].
Fatigue Properties.
Mai, Laser shock processing and its effects on microstructure and properties of metal alloys: a review, Int.