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Therefore, identifying the nature of bonding force between C-S-H clusters becomes the striking point to understand the cementing properties of the cement pastes.
With appearing the atomic force microscopy (AFM), the properties and characterization of bonding forces between C-S-H clusters in concrete have become the focus of the research recently.
AFM becomes a popular tool in studying the three-dimensional structural characteristics of materials, meanwhile nanoscale mechanical properties of the sample surface by means of force-distance curve [4].
Therefore, it would be applied to reflect indirectly the nanoscale mechanical properties of the cement-based materials.
Through analyzing the main influencing factors, the validity of bonding force results is assured, which lay the foundation for simplifying the method of the measuring force values.

In the multibody dynamics analysis for motor vehicle, engine excitation, as a major excitation affecting the dynamic behavior of motorcycle frame, should be discussed.
Introduction Dynamics analysis for complex mechanical system in research and development process has been an important technique, especially for the systems with higher speed and less weight, and the study on the major performance of vehicle, including dynamical property, safety, durability and fuel consumption economy, should not be performed only with simplified model or single DOF model.
Although many manufacturers of vehicle and spacecraft have applied CAE technique to perform their dynamic analysis for mechanical system, seldom literatures are still released to discuss about the dynamics of multibody system of complex mechanical products.
In Lagrangian equation with Lagrange multiplier, the rigid body is presented by generalized coordinate of Cartesian coordinate and Euler angles expressed in qi=[x,y,z,Ψ,θ,ϕ]iT, as multibody system consists of n bodies presented as qi=[q1T,q2T,⋯,qnT], the kinematical equation of motion for mechanical system is second-order differential algebraic equation by Eq. 1: (1) ddt[∂T∂q]T-∂T∂qT+λϕqT+μθqT=Q Where: T is kinetic energy; q is generalized coordinate matrix; Q is generalized force matrix; λ is holonomic constraints Lagrange multiplier factor matrix; μ is non-holonomic constraints Lagrange multiplier factor matrix; ϕq,t=0 is holonomic constraint equation; θq,q,t=0is non-holonomic constraint equation.
Summary Definitely, computational simulation on multibody dynamics analysis for complex mechanical system has been a necessary approach in research and development process.

The results of experiment prove that the transition point of the cone-shaped head of the solid rivet, the size and position of groove affect directly the quality of riveting.
Blanking force is affected by many factors, such as the mechanical properties of materials, sheet thickness, the die-clearance, the velocity of punch and so on, but the most important factors are the sheet material and thickness.
The stress concentration appears around cracks from the numerical simulation, and the quality of riveting is affected.

Since normal shock absorbers can’t meet these special requirements result from multiple factors of the space environment, magnetic fluid damping shock absorber based on the principle of magnetic liquid second-order buoyancy is best candidate to meet this requirement.
It has two features: one is that magnetic fluid contains magnetic particles in the fluid kept doing Brownian motion, solid-liquid separation will not occur even in gravity, magnetic, centrifugal force; The other is, being super magnetic liquids in external magnetic field, magnetic fluid has a corres- ponding magnetic properties, viscosity, rheology, and birefringence and other unique properties [2].
From the above analysis, there are two key factors to affect the damping effect: first, the relative velocity between magnet and shell; second, the shear stress which can be considered as friction force between magnetic liquid and the surface of shell.
Angle of gasket du/dy Fig.3 Experimental curve Fig.4 Fluid shear stress and the velocity gradient: (1) Bingham fluid, (2) Newtonian fluid, (3) ideal fluid Being affected by magnetic field, magnetic fluid will have certain properties of the solid, so it can be regarded as Bingham fluid.
Wang, Study on the Preparation and Properties of the MRF, Journal of Functional Materials. 3 (2001) 257-261

It was observed that the cutting speed is the most significant cutting parameter affecting the durability of edge.
The cutting speed and feed rate affecting the tool life for T1 by approximately 60% and 20% respectively and by about 66% and 30% for the inserts T2.
Applied Dijkstra's algorithm requires the assumption of constant values of weighting factors k1 and k2.
ANOVA analysis indicates that the cutting speed and feed rate were affecting the tool life about 60% and 20%, respectively (the first type of the cutting tool) and by approximately 66% and 30% respectively (the second type of the cutting tool).
Dyachkova, On the properties and tribological behaviors of P/M iron based composites reinforced with ultrafine particulates, Composites Part B: Engineering. 58 (2014) 16-24

Furthermore, many authors have reported that nanocomposites show many interesting properties as compared to ordinary composites, such as high mechanical properties (e.g.
It has been reported that the electrical properties of many electroceramics affect by many factors, such as dopants and fabrication technique.
LCR meter (Agilent E4980A) was used to measure for the electrical properties.
In some cases for ceramic – metal interface, the Schottky barrier was found to depend on many factors such as the type of electrode and the ceramic treatment.
However, other factors that effect to the electrical properties of the ceramics should be clarify for further work such as processing parameter for forming electrode.

Mechanical properties of core areas of joints are complex affected by many factors.
Many scholars study mechanical properties of beam-column joints through the testing method.
Joints Design and Material Properties This test researches one specimen under reversed cyclic loading, in which yielding firstly occurs at beam ends and shearing failure secondly occurs at joints [1].
The plastic deformation of the concrete is determined based on tension damage factor dt and compressive damage factor dc.
Based on the energy equivalence principle, concrete constitutive model is determined by Equation (4) ~ (5) considered damage factor

In this study, the effects of laser parameters on the properties of glazed die steel were investigated.
Scanning Electron Microscopy (SEM) micrographs and micro-hardness properties of the affected surface were measured.
Micro-hardness properties of the affected surface were measured using Leitz mini-load tester with 981 mN force.
Physical and thermal properties of the H13 die steel used for the modelling are given in Table 2.
Table 2: Thermal and physical properties of H13 steels at room temperature [23].

The influence of TMT and cooling rates on the final magnetic properties of the alloy were investigated.
Introduction Fe-Cr-Co is magnetically hard alloy having good magnetic properties in combination with high mechanical characteristics.
These results suggest that microstructural properties are affected by the mode of quenching.
Magnetic properties analysis: The two major factors that influence the magnetic properties are volume fraction of the spinodal decomposition product phases along with their shape and their composition difference.
Upon the decomposition, molybdenum concentrates in paramagnetic phase α2 and causes lattice parameter difference between α1 and α2 phase, thus affecting the morphology of the precipitated phases [1,5,6].

This can give the basis for the thermal fatigue properties study of the particle reinforced composite SiCp/A356 used in high-speed train brake disc.
The particle reinforced composite material SiCp/A356 is used in high-speed train brake disc because of its high strength, wear and thermal resistance, but its fatigue property need to study.
The research methods of thermal fatigue properties are as follows [4]: strain range-thermal fatigue life, strain range partitioning method, equivalent temperature method, temperature amplitude- the number of thermal cycle method and average/maximum temperature-thermal cycles law. because of the complexity of thermal fatigue test, people try to use the high temperature mechanical fatigue test to replace thermal fatigue one [5-7]. while the constant high temperature mechanical fatigue does not reflect the range of temperature and strain, it is not reasonable enough to use.
Thermal fatigue performance of composite SiCp/A356 The forecast model of low cycle fatigue life(Nf) taking into account the average stress, , is as follows: (1) Where is the fatigue strength factor, the fatigue strength index, the fatigue ductility factor, the fatigue ductility index, the elastic modulus.
Fig.4 Contrast between thermal fatigue stain life plot and high temperature ones We can find that from the above analysis the temperature and strain range are important parameters which can affect thermal fatigue performances.