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China 2 School of Mechanical Engineering, Shandong University, Jinan 250061, P.
On Fixation I, the stress concentration mainly appears in the belly, on Fixation II, stress concentration mainly occurs in the attachment edge, which can affect the long term durability of leaflets.
The Fixation I contribute to better mechanical behavior of leaflet, which may has a significant effect on the long term durability of the value.
The ELV is superior to the CLV in mechanical properties.
Li, Geometrical Stress-Reducing Factors in Anisotropic Porcine Heart Valves, Journal of Biomechanical Engineering, vol.125, pp.735-743, 2003

Superior mechanical and durability properties of RPC are achieved by appropriate mixture design and curing conditions [4, 5].
Thus, it is possible to suggest that aggregate blend where β value results in the highest packing degree will results in the RPC mixtures with highest strength if other mixtures design factors are held constant.
Aggregates classification based in the sieve analysis test results, and their properties determined as required by ASTM C128 and ASTM C29 are provided in Table 3 [16, 17].
Properties of sand blends required for concrete mixture design (MC, AC and specific gravity) were calculated from properties of sand fractions given in Table 4.
Influence of ultrafine 2CaO· SiO2 powder on hydration properties of reactive powder concrete.

Further more, cracks will cause housing leakage and affect the aesthetics of buildings.
Causes of crack formation is complex, crack damage degree is not only relative to crack size but also relative to crack property and structure function requirement.
As a result, we should ascertain exact reason of cracking, treat with factors that causing crack, and take different proper measure to different kinds of building crack.
Row Material and Environment Factor.
For those cracks that are not load crack, though the crack will not affect structure safe, but must be take into account also because house are all-important personal estate and crack may affect beauty and function of building.

Based on the mechanical and deformation characteristic of this tall structure, the bottom stories and stories above the strengthened ones are selected as the "key stories" to control the performance of the building.
It is emphasized that the irregular structure of the degree of ductility directly affect the level of deformation.
For structural engineers, structural properties can be explicitly described physical state are: force, displacement (stiffness), velocity, acceleration, energy, and damage.
Displacement based seismic design can be roughly summarized as follows: a method designed by the ductility factor, capacity spectrum method and the method directly based on displacement [4].
Tall building beyond the highly regulated in various regions of the structure of tall buildings, high aspect ratio limit in many ways, using standardized methods does not ensure good design force and deformation properties.

Surface roughness is an important geometry accuracy indicator which has a significant impact on the parts' mechanical properties, service life and reliability in using.
Among the many factors that affect the surface roughness of the grinding process, cutting parameters play a decisive role which includes the grinding wheel speed, the rotating speed of the part and the grinding depth of the wheel.
Yang: Chinese Journal of Mechanical Engineering, Vol. 45 (2009) No.10, p. 254.

In addition, the porosity and tortuosity are the two most significant factors affecting the chloride ions penetration for alkali-activated fly ash concrete.
Mechanical and microstructural properties of alkali-activated fly ash geopolymers.
Effects of Dosage and Modulus Ratio of Alkali-Activated Solution on the Properties of Slag Mortars.
Setting and mechanical properties of alkali-activated fly ash/slag concrete manufactured at room temperature.
Strength and shrinkage properties of alkali-activated slag concrete containing porous coarse aggregate.

The shear wave velocity of the soils is affected by many factors, such as geologic origin, buried depth, thickness of covering soil layer, soil condition and so on.
Taking into account the feasibility of statistical analysis, the quaternary stratigraphy of the Bohai Gulf roughly be divided into four types including silt (sandy silt included), fine sand (silt fine sand included), silt (sandy silt included), clay (sandy clay and silt clay included) according to factors such as lithology, genesis, physical and mechanical properties.
Statistical analyses Statistical method Plenty of studies have confirmed the discipline that the shear wave velocity of rock and soil mass increases along with the depth increasing, but the relationship is relatively complicated, and the growth is not a simple linear relationship due to the diversity of the factors influencing the shear wave velocity.
However, it should be possible to carry out the testing of the shear wave velocity due to the many factors affecting the shear wave velocity.
Correlation Analyses between Shear Wave Velocity and Ground Properties of Kunming Basin[J].Journal of Kunming metallurgy college, 2006, 22(3): p.1-5

This was explainable by their respective separation factors (RL),which indicatedhigher favorability of kaolin for Pb than for Cu.
The mixture was then placed in a mechanical shaker and shaken for 24h at room temperature (25±1°).
AdsorptionIsotherms.Isotherm models are used to describe adsorption reactions, with parameters of the equation expressing the surface properties of the adsorbent.
This was explainable possibly by their respective separation factors (RL), which indicated higher favorability of kaolin for Pb over Cu.
Ipýldak, “Adsorption properties of stearic acid onto untreated kaolinite,” Bull.

Speed Control System Design of Winding Mechanism For Composite Films Y.H.Du1, a , X.M.Jiang 1, b and G.Y.Yang 1, c Mechanical & Electronic Engineering College, Tianjin Polytechnic University, China a duyuhong@tjpu.edu.cn, b jiangxiuming@tjpu.edu.cn, cyanggongyuan@tjpu.edu.cn Keywords: Winding Mechanism, Ratio Control, Mechanical Model, Control Strategy.
In addition, the imbalance of tension will result in the offset and drift, and thus the quality is adversely affected[3].
ds JJJJ ++= 303 (2) According to the winding material properties, the moment of inertia Js is: 44 330() 2 s rbq Jrr π =− (3) where Js is the equivalent moment of the composite films; ρ is the composite films mass density of unit width; q is the space factor; r 3 is the radius of the winding shaft; γ is the proportion of the composite films; g gravity acceleration; b is the width of the composite films.
With these strategies, the dynamic property is improved and the tension is stabled.
Through industrial applications, it is demonstrated that the developed system has the properties of structural compactness, high automation and reliability.

Especially, the study and analysis are made for some main factors, such as formation of magnetic field, design of permanent magnetic circuit, shape of magnetic pole, preparation and property of magnetic abrasive powder.
Furthermore, with the NC machine tool, the finishing of complicated curved surface was carried out, the technological parameters affecting the processing quality are optimized, in which permanent magnet takes the place of electromagnet.
The manual method does not conform to the demands of modernized manufacture because of its low productivity and high labor intensity, and also because the machining quality often relies on the subjective factors out of operators.
Thus, magnetic abrasive powder with high performance is one of the essential factors to handle both machining efficiency and quality.
The analysis for how magnetic flux density and magnetic pole’s rotational velocity is affecting the machining result respectively is given in next section.