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The multi-path fading is an important factor which affects the wireless channel capacity and the transmission quality.
Nonetheless, due to the affection of the power, quality and volume of the mobile terminal, many antennas are designed in base stations in actual mechanical process, so that the received actual improvements are far from what we have expected theoretically.
Agreement on cooperative diversity Cooperative diversity has various forms, and different forms are different in their complexity and properties.
Sendonaris A’s research indicates that coding cooperation prefers to sacrifice the users’ property of relatively good quality in the fast fading environment.
Of course, in certain environment, it needs to find the balance point between the property gain and the complexity.

The forming mechanism of filter rod, equipment vibration and other interference factors all lead to fluctuations of precision of filter rod circumference which can affect the precision of the cigarette.
Tiny jitter of filter rod, the equipment vibration and other interference factors all lead to the fluctuation of filter rod circumference precision.
Its advantage is that own independent intellectual property rights and achieve popularization because of its low price.
[3] Fang Li, Li Fu and Yang Fa: Mechanical Engineer.

The objective of this study is to investigate the effects of activating fluxes on the weld bead geometry, hot cracking susceptibility and mechanical property of A356 and 6061 aluminum alloy dissimilar welds in the gas metal arc (GMA) welding process.
The weld bead geometry of welds plays an important role in determining the mechanical properties of the welding specimens.
The purpose of second stage is to investigate the effect of activating flux on the hot cracking susceptibility and mechanical property of A356 and 6061 aluminum alloy dissimilar welds.
Effect of Activating Flux on Mechanical Property of GMA Welds.
Fig. 8 shows the comparison of the mechanical property of conventional welds and GMA welds made with four single-component fluxes.

Grid of finite elements have been given the appropriate parameters and properties.
The air does not move, which directly affects the aerodynamic drag forces.
In the vicinity of these zones an air turbulence may occur, which indirectly affects the results, making a flow more turbulent.
Moreover, thanks to engine test stands the capabilities of measuring apparatus are getting wider and repeatability of work conditions is provided, which is hard to achieve on a track. [5] There is also a possibility to evaluate and analyse impact of particular factors on measured parameters. [3,4,8] The main aim of research was to compare results received from an actual engine test stand with ones received from computer simulation on a model.
Using computer simulation determining kinematic and dynamic properties of bolides’ elements is possible.

Measuring Threshold Pressure of Melt Magnesium Infiltrating Into Al2O3sf Porous Preform with Fast Method Zhou Jiming1, 2, a, Gu Xuehua1,b, Yang Fang1,c, and Qi Lehua1, 2, d 1 School of Mechanical Engineering, Northwestern Polytechnical University, Xi’an, P.R.China, 710072 2 The Key Laboratory of Contemporary Design and Integrated Manufacturing Technology, Ministry of Education, Xi’an, P.R.China, 710072 azhoujm@nwpu.edu.cn, b guxuehua1027@163.com, cgwj@nwpu.edu.cn, dqilehua@nwpu.edu.cn Keywords: metal matrix composites (MMC); liquid metal infiltration; threshold pressure; capillary phenomena.
If the pressure is so large that the reinforced materials could not withstand, the preform may be crushed to weaken the property of the composite.
Experiment materials and procedures The AZ91D magnesium alloy was used in the experiments, and the main compositions and properties were given in Table 1.
Table 1 Compositions and property parameters of AZ91D magnesium alloy Al Zn Mn Si Mg Density[g/cm3] Solidus[℃] Liquidus[℃] 8.5～9.5 0.45～0.9 0.17～0.3 ≤0.05 Bal. 1.81 470 595 Table 2 Compositions and parameters of Al2O3 fibre component metallographic Length[µm] Diameter[µm] Density[g/cm3] tensile strength[MPa] SiO2<20% Al2O3>80% α- Al2O3sf >50 3-10 3-5 1130 Fig. 1(a) shows the schematic diagram of the developed infiltration measurement device.
Louis, Factors affecting pressure infiltration of packed SiC particulates by liquid aluminum, Metall.

Strain due to phase transformation, transformation plasticity and thermal expansion are the dominant factors that need to be included in the simulation of a quenching process.
Introduction In order to obtain improved mechanical properties and fatigue strength of machine components, such as gears, shafts and so on, a carburizing-quenching process as a method of surface hardening is often used in industry.
In quenching process, strain is caused by phase transformation and transformation plasticity and thermal expansion, which are important factors to be able to predict and simulate deformation after quenching.
Summary of theoretical modeling In a quenching process, the effects of metallic structures and stress/strain and temperature are intertwined affect one another.
Of Materials and Heat Treatment, Vol. 25, No.5, Chinese Mechanical Engineering, pp.28-34(2004).

Factors, such as radiation, extreme heat cycles, and low pressure are the common environmental conditions a CubeSat will encounter in space.
The comparisons in Table 2 are based on specific material properties using a standard test piece.
In addition, to control the desired mechanical properties and reduce defects induced during printing, post-processing such as heat treatment, stress relief, solution annealing, and ageing are considered.
These thermoplastics offer remarkable chemical resistance and excellent mechanical properties even at elevated temperatures.
This process is necessary to maintain its mechanical strength and modify its mechanical properties, depending on the application, by varying the time and temperature in the heat treatment process.

In addition, the profile milling with shaping is different at kinematics and dynamics of the cylinder [33, 34], so for the analysis of the geometric accuracy of the treated surfaces it is necessary to have mathematical models linking the indicators of surface's geometry with dominant factors of the process: the elements of cutting mode, and the parameters of the cutting tool [28, 35].
These errors will eventually affect the deterioration of surface roughness and waviness of the product surfaces in the end.
Analysis of Geometric Errors We will analyze the geometric errors of surfaces treated with shaping cutter and emerging under the influence of its specific design elements and we will not consider the factors that characterize the milling mode (feed vs, cutting depth t, the angular velocity ω) and the number of teeth Z, because their impact on the errors of treated surfaces is quite well known.
Gusev, Safe machining of blanks with nonuniform properties, Russian Engineering Research, 33(10) (2013) 602-606
Gusev, Spindle Rigidity in Milling Blanks with Nonuniform Properties, Russian Engineering Research, 33(11) (2013) 646-648

Moreover, the structural and morphological properties of the nanostructures were examined.
Low-dimensional materials have attracted much interest because of their enhanced or modified optical, electronic and mechanical properties compared to those of bulk materials.
It is considered that one of the key factors to obtain a dense nanowire bundle is the formation of high density catalytic nanoparticles covering the substrates.
The surface energy is one of the major factors that affect the growth direction of the nanowire or nanobelt [16].
Kuwabara, Structural properties of zinc-blende MnTe layers grown by hot-wall epitaxy, Appl.

Composite manufacturing processes and their effects to the material properties are cited.
The achievement of this kind of model is difficult since damage factors could be adjusted for FE results to give a valid solution without experimental correlation.
First of all, through-thickness properties need to be obtained in order to constitute input data of the numerical models, in addition to standard in-plane properties.
Woven fabric plies properties are used.
Effect of cure cycle heat transfer rates on the physical and mechanical properties of an epoxy matrix composite.