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Depending on the integrity of its design and material properties, the coil spring can return to their original shape and size when the force is released [4].
NS ≥1.2 Where NS is given as the factor of safety at closure.
High corrosion resistance Material Properties Table 2 shows selected material properties for high carbon steel, stainless steel and Chrome vanadium which are the three major materials analysed in this study.
The loading conditions discussed in this study are not the only factors that affects the performance of a typical helical compression coil spring but other factors such as inherent defect in the raw material (prior to manufacture), improper heat treatment, decarburization, inclusion, surface imperfections due to poor shot peening can also constitute to spring failure.
[15] Acxess Spring, Properties of Common Spring Materials for Spring Wire.

By testing heat transfer coefficient of four kinds of masonry walls, different aggregate type, masonry unit type and insulation material which affect thermal performance of masonry were studied.
Research on thermal properties of self-thermal insulation concrete block from construction waste[C].
Research on mechanical and thermal performance of composite heat preservative concrete block [J].
Utility Model Patent, No. 3394918, State Intellectual Property Office of the People’s Republic of China, 2014. ]were produced by ourselves which were composed of dry concrete using particular devices and large amounts of researches have been done on strength characters and shrinkage of blocks previously [[] X.X.
Analysis of influence factors of compressive strength of concrete block [J].

Whether there are involved new buildings or old buildings, knowing the concrete properties (mechanical or physical) is a fundamental issue, in order to assure the structural safety.
The obtained results by testing the sample to compression by using a hydraulic testing machine is revised by the help of several, different correction factors: depending on the core diameter, its height/diameter ratio, the moisture content due to sample conditioning of the nature of the leveling layer and the presence of reinforcement bars passing through the cores [2].
A slightly different concrete mix can influence the UPV measurements, thus affecting the accuracy of results and the evaluated compressive strength, which basically remains the same or varies insignificantly [10]. 2.2.
The value of E depends on several factors, such as: the binder characteristics and proportions of binder(s), the dosage of cement, concrete age and also its class.
The natural frequency is a dynamic property of any system.

In fact, studies [1,5] have brought attention early on to severe reduction of mechanical properties caused by the ageing process of specific resin matrices used in composite reinforcement materials, or, even more perilous, their exposure to extreme conditions of temperature.
This is because a number of factors make it advantageous as the choice of restoration materials: among others, the growing attention to reversible and compatible materials, the easy application of fibre reinforcements, and their light weight.
Within this preference, Fibre Reinforced Polymers (FRP) have proven to lose mechanical properties [4, 8] during the ageing process or due to prolonged exposure to elevated temperatures.
The results of these previous experimental campaigns have lead the authors to a new research question on how the ageing process of mortar, commonly used in reinforcing techniques such as Fibre Reinforced Cementitious Matrix, reinforced plaster and Reticula [3], may affect the structural behaviour of the fibre itself.
The flexural strength of the MX mortar specimens was considerably higher than the lime and cement mortar prisms, as was to be expected given the reinforced nature of the mortar itself and the high mechanical characteristics of the PBO fibres.

Key words: coatings, calcium phosphate, HA, plasma-spray, electrochemical deposition, precipitation, implants Introduction Titanium (Ti) and Ti alloy (Ti4Al6V) are the metals of choice for the manufacture of dental and orthopedic implants because of their desirable properties that include: corrosion resistance; biocompatibility; strength and presence of reactive titanium oxide on the surface [1].
Furthermore, the very high temperature involved in the plasmaspray process will not allow the incorporation of biologic molecules (e.g., growth factors) that have been shown to increase and enhance bone formation.
These include mechanical or chemical surface treatments with or without calcium phosphate coating deposition.
The low temperature methods allow the deposition of coating with homogeneous composition, uniform coating of implants with complex geometry and macroporosities and incorporation of biologically active molecules (e.g., growth factors), if desired.
Furthermore, low temperature allows the incorporation of bioactive molecules (e.g., growth factors) in the coating to enhance bone formation.

Generally speaking, HAS are composed of hydraulic servo actuator (HSA) and Power-by-Wire Actuator (such as electro-hydrostatic actuator (EHA) and electro-mechanical actuator (EMA)).
Fig.1 Structure schematic of HAS Fig.2 The air load force of the control surface 1.2 The model of the control surface As is depicted in Figure 2, the air load force of the control surface can be divided into two parts: the hinge moment in the smooth flight condition and the additional air load caused by uncertain factors like gust.
Assumption: the lift isn’t affected by the surface’s deflection, namely, it won't change the angle of attack, which will not influence the analytical results.
Position feedback is used to improve the system stability; velocity feedback is mainly used to increase the static accuracy by improving the static stiffness of the main loop, reducing the influences of the loop internal disturbance and nonlinear factors; acceleration feedback and pressure & dynamic-pressure feedback aim to add the damping ratio and improve the comprehensive properties.
Aircraft systems: mechanical, electrical, and avionics subsystems integration [M]. 3rded.

The material properties of wires under scrutiny are validated by a tensile test and by the values of datasheets.
Always higher copper fill factors and more-complex-winding schemes are needed to optimize electric drives [6].
All the mechanical and physical properties of the copper wire in accordance with [12] are saved in the material database.
First of all the imported geometry is highlighted and the before created material properties are allocated to each body.
Because of being the most important parameter for affecting accuracy and convergence behaviour it is significant to know that a large value of stiffness results in better accuracy but engages convergence difficulties.

Vibration Analysis of High-Speed Vehicles under the Condition of Track Random Irregularity Hongmei Shia, Jialiang Zhoub Beijing Jiaotong University, School of Mechanical and Electronic Control Engineering Beijing, 100044, China a hmshi@bjtu.edu.cn, b 09121827@bjtu.edu.cn Key words: Track irregularity, Vehicle track coupling, Numerical integration, Vibration analysis Abstract.
The geometric state of the actual lines is affected by many random factors including rail initial bending, rail wearing, uneven space of rail sleepers and the variable mass, uncertain intensity, loosening and elasticity of ballast bed, subsidence of roadbed, stiffness changing, etc.
Random Vibration Property of High-Speed Railway Vehicle in Passenger Dedicated Line [J], Journal of Southwest Jiaotong University, Vol.45(2010), p. 191-195

The advantage of such a platform is that the mechanical design is far simpler than competing conventional approaches. 1 The system research of planar platform The whole system of planar platform include platform, driving motor, and sensors and so on, as Fig.1.The work piece which will be detected is put to the platform, and driving motor can make the platform move freely, the sensor can detect the displacement distance, the motor is the magnetic linear motor, it has a lot of advantage, for example low resistance/high accuracy and so on.
Fig.1 Construction of the platform 2 System hardware circuit design The property of platform is affected by the structure, material, and technology and so on, control system hardware design is one of the key factors of the platform which based on the structure optimization design, and it can realize the desired precision, rigidity, stability and so on.

Since the inner pressure of the pore balances with the flow stress of bulk metal at the interface, the temperature affects the evolution behavior of the pore through its influence on the flow stress of the bulk metal primarily.
Introduction Since the 1940’s, 7xxx series aluminum alloys had become one of the most important structural materials in aerospace industries. 7xxx alloys were promoted by advanced airplanes directly, developing from pursuing single property to pursuing excellent comprehensive properties, and the products developed from small to large dimension [1].
As the most widely used aluminum alloy in aerospace industry, 7050 alloy has excellent comprehensive properties with high strength, high toughness and high corrosion resistance.
However, when it is applied to produce thick plates, pre-stretching plates and forgings with large section dimensions, defects such as pores and inclusions have become the key factor that restricts the dynamic mechanical properties, stress corrosion resistance and performance stability [4-7].
(3) The flow stress change caused by different deformation temperature is the primary factor which leads to the change of the plateau volume Vp of the pore.