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In this sense, research studies are oriented to the optimization of the mechanical properties of the pieces through the parameters of the manufacturing process, analyzing how they affect the anisotropy and mechanical resistance of the piece.
The most dangerous defects that can occur during the manufacturing process are mainly due to cracks (with a degree of affectation on the mechanical and aesthetic properties of the object according to the dimensions of the crack), porosity (distributed throughout the entire volume of the piece and that affect its mechanical properties), local pore groupings (can give rise to cracks during the operational life or in service of the object), residual stresses (can cause deformations, loss of geometry and formation of macro-cracks) and the possible influence of surface roughness on the fatigue resistance of the final product, a subject that is still under study today [9, 10].
Through the processing and analysis of images acquired by a LWIR thermographic camera, it is intended to obtain variables and indexes that influence properties related to the quality of the parts.
Martínez-Ramos, “Influencial factors in thermographic analysis in substations,” Infrared Phys Technol, vol. 90, pp. 207–213, 2018, doi:10.1016/j.infrared. 2018.03.014
Standard Test Method for Tensile Properties of Plastics.”

The main properties of the wood-plastic composites Properties Data REMARKS Density (g/cm3) 1.1-1.5 Water absorption (%) <0.2 Soaked in water for 24h.
Guo, Process factors and performances of recycled plastic wood fiber composites, Journal of Beijing Forestry University 27 (2005) 1-5
Oksman, Mechanical properties and morphology of impact modified polypropylene wood flour composites, Applied Polymer Science, 67 (1998) 1503-1513
Raj, et. al, Effect of chemical treatment of fibers on the mechanical properties of polyethylene-wood fiber composites, Adhension Science Technology, 3 (1989) 55-64
[5] Wu J, et. al, Effects of fiber pretreatment condition on the interfacial strength and mechanical properties of wood fiber/PP composites, Applied Polymers Science, 76 (2000) 1000-1010

The scatter is related to a multitude of random factors that exert a cumulative effect onto the material.
However, the main factors that determine strength and durability of composite materials include the degree of non-uniformity and defectiveness of a structure [5, 6].
Adding of various kinds of powdered fillers changes the properties of epoxy composites in a quality manner.
The nature of such phenomena depends greatly on the reactivity of the filler and the characteristics of surface topology, which affect significantly the properties of the material and their variation during operation.
Faber, Effect of interface properties on microcracking of iron titanate, Scripta Mater. 38 (1998) 1449-1453

(2) Overcoming shortcomings of each other, improving the properties of yarn.
Different fiber distributes differently on the cross –section of the yarn because of the different morphology and mechanical properties of fibers, thus the blending yarns have different look and performance.
Therefore, the natural fibers should be blended with finer and longer chemical fibers to get better hand, for example, when PET, bamboo fiber and cotton were blended, the hand and comfort of cotton , the good mechanical properties of PET and anti-bacteria properties of bamboo can be gotten when the PET and bamboo fiber is longer and finer than the cotton fiber[6]
Secondly, the blending ratio is one of the most important factors that affects the performance of the blending fabric.
Spinning ways affect the mechanical properties and look of the yarns, and the performance of the yarn is influenced by the spinning ways also.

Based on Betz Theory,Simplified Theoretical Model assumes that wind turbine works under ideal conditions ignoring axial, circumferential interference factors and vortex distribution of blades.
Glauert Theoretical Model founded vortex system of the wind wheel considering axial and circumferential interference factors.
As the moment arm of airfoils in blade root is too small to make enough contribution to the output torque of wind wheel, the property of wind turbine is less affected by blade root, where the convenience of manufacturing and strength is mainly considered.
Journal of Mechanical Engineering, 2010, 46(3): 131-134
Mechanical & Electrical Engineering Magazine, 2006, 23(4): 37-40

Introduction The hydration of cement and the accompanying phenomena such as heat generation, strength development and shrinkage are the results of interrelated chemical, physical and mechanical processes.
In the past, several interesting concepts have been proposed to simulating the hydration and microstructure development of concrete and the research of macroscopic physics mechanical property.
In addition, cement hydration process are impacted by several factors, such as water-cement ratio, chemical composition of cement, fineness, curing temperature and humidity, so it is necessary to build the hydration microcosmic model.
In the past research, many researchers discovered several influence factors of kinetics, such as chemical composition, water-cement ratio, fineness, curing temperature, etc [7].
The effective diffusion coefficient of water is affected by the tortuosity of the gel pores as well as the radii of the gel pores in the hydrate.

A Finite Element Analysis on SAW Sensor for Torque Measuring Lijiu Wang 1, a *, Yuntao Zhang 2,b 1 Key laboratory of Fundamental Science for Advanced Machining, School of Mechanical Engineering, Beijing Institute of Technology, Beijing, 100081,China 2 Key laboratory of Fundamental Science for Advanced Machining, School of Mechanical Engineering, Beijing Institute of Technology, Beijing, 100081,China awanglijiu@bit.edu.cn, 24728,byuntao@163.comdu.cn Keywords: Surface Acoustic Wave , FEA, SAW Sensor Abstract.
Torque measurement based on the SAW technology has advantages of high measuring accuracy, fast response and passive wireless property, overcoming disadvantages of strain gauge measurement, grating measurement, etc.
There are many factors that affect the strain transfer.
By studying the relationship between these factors and strain transfer, we will provide a theoretical basis for optimizing the design of sensor structure.
The sensitivity study focuses on the thickness and the elastic properties of the adhesive layer.

., Beijing 100070, China awxgao@bjut.edu.cn, bzucheng@emails.bjut.edu.cn, c54houbinghui@163.com, dchenningning@emails.bjut.edu.cn Key words：High Cutting Slope；Blasting For Excavation；Dynamic Stability；Numerical Simulation Abstract：The impact of blasting effect is an important factor of dynamic stability in the excavation of rock slope.
The impact of blasting vibration on stability of rock slope is mainly manifested in two aspects: firstly, repeatedly blasting vibration load disturbance causes further expansion of jointed rock mass and increased loose deformation which results in the deterioration of mechanical properties of rock and make the road cutting slope unstable, especially high and steep slope.
Physical and mechanical parameters of the site area of limestone is as Table 1shows Table1 The physical and mechanical parameters of limestone Rock types Modulus /GPa Internal friction angle /0 Cohesion /MPa Tensile strength /MPa Density /Kg·cm-3 Limestone 45 36 25 6 2550 Calculating Model And Parameter Selection According to foundation excavation terrain conditions, the numerical simulation takes the final object of the excavation slope as a blast load.
To simplify the analysis process, we assume the cutting numerical simulation of rock slope excavation as the following: (1) Equivalent uniform loads acting on the same line hole blasting area where the plane with center line, Load strength depends on the medium properties, distribution methods and the charge quantity
These new inclined cracks may affected the original structures of the rock slope, the transfixion cracks might occur, it would reduce the anti-sliding ability of the rock slop, form slippery body and result in the un-stability of the slope.

Introduction As we known, wood is a viscoelastic material and therefore its mechanical properties are affected by temperature [1].
Based on temperatures, time-scale is also an important factor influencing the strength properties.
The effect of temperature on the mechanical properties of wood can be categorized into two classes: reversible effects, which refer to transient changes in mechanical properties at temperatures below 100ºC, and irreversible effects, which are brought about by the thermal degradation of wood constituents at high temperatures.
Effects of temperature on the mechanical properties of beech (Fagus orientalis Lipsky) and lime (Tilia begonifolia) wood.
Compression mechanical properties of wood at temperatures simulating fire conditions.

These 4320 samples were selected based on their distortion characteristics as well as their mechanical properties.
“Overview of residual stress after quenching part II: factors affecting quench residual stresses,” International Journal of Materials and Product Technology 24 (1-4), (2005): 53-97
Equipment, Process and Properties of Modern Austempering, edited by Keough, W.
[16] Parrish, Geoffrey, The Influence of Microstructure on the Properties of Case-Hardened Components.
"Factors Influencing Austempering."