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Many studies had shown that Sn-Ag-Cu solders (SAC) possessed superior mechanical properties such as high strength, good ductility and long fatigue life.
Dendrites growth was another factor affecting the reliability of solder joint in electronics packaging.
The another factor affecting on whisker formation was absolutely relative to the formation of IMC (intermetallic compound), Zn and Bi doping in SAC solder cannot eliminate IMC formation, which can cause the compressive stress on the solder alloys, so whisker growth was inevitably.
Electrochemical migration properties of SAC solder could be suppressed by Bi addition, which the contrary effect suitable to Zn addition.
In order to attain the excellent characteristics of SAC solder, these factors on reliability would be considered evenly.

Change of groundwater level is one of the most important factors of landslide prediction.
Previous studies on groundwater of landslide were mainly about slope stability of mechanical mechanism, but for variation of groundwater level of landslide area is scarce studied.
In this paper, monitoring groundwater level of K144 landslide two years, we contrast groundwater level of landslide zone and potential deformation rising and falling, study on variation of groundwater level which affect k144 landslide reactivation.
In order to ensure the safety of people's lives and property and keep the National Highway G65 unblocked, relevant departments simply cleared earthwork of the landslide surface .
Some scholars who calculated slope stability affected by groundwater found when groundwater level of colluvial landslide increase of 0 1H, the stability coefficient reduced 0.05 ~ 0.07[9].

Welding, which is a largely used process in the mechanical manufacturing, well known to induce high-level residual stresses.
The level of residual stresses is of great importance for the lifetime of welded components used in mechanical engineering industry.
The residual stress states in welded parts result of variety of parameters like material properties, geometry of the joints and the welding process.
They range from destructive methods like the hole-drilling method to a large number of non-destructive methods based on X-ray or neutron diffraction, photo-elasticity, or the determination of magnetic properties and ultrasonic measurements.
In the present paper, we performed complete calibration measurements on parts extracted from PM and MZ to improve the microstructure correction factor.

According to the designers' understanding, diverse texture properties of the material give people diverse feeling whenever and wherever.
Such reference method in design breaks the rules of strict use of material and the old process, translating the impossibility factors into the real possible design element [8].
On one hand, cross-border conflict would attract people’s more attention, on the other hand, similar factors would speed up people’s understanding and the process of adaptation.
The way of reference is a challenge to the conventional material properties.
The superposition and integration we point out here build on the casual factors and get inspiration from the random material resources and in the end to display different creative products.

In addition, more and more materials of better properties have been developed and utilized for fabricating such products.
Similar to electrical discharge machining (EDM), ECDM is not affected by the strength or hardness of the materials.
These bubbles coalesce and form an insulating gas film, whose structure and stability would affect the machining performance.
Factors influencing the structure and stability of gas film include dispersion of bubbles, replenishment of electrolyte, voltage supply, current density, and shape of tool electrode.
The workpiece is made of quartz, which has been widely applied in micro electro-mechanical systems (MEMS). 

Concrete Mixture Properties.
According to Chinese specification (JGJ55-2011) [7], the properties of concrete mixture are obtained as shown in Table 1.
Table 3 Test results of concrete Strength grade Chloride diffusion coefficient [10-12m2/s] Cube crushing strength [MPa] 56d 84d 7d 28d C20 7.45 4.78 16.9 23.4 C30 4.05 2.48 24 38.2 C40 3.14 1.68 34.4 46.5 C50 2.35 2.11 40.3 52.2 Microcosmic pore structure properties results of different strength grade concrete specimen at different age are shown in Table 4.
Water-binder ratio is the most important factor that affecting the pore structure of concrete.
[11] GB/T 50081-2002, Standard for Test Method of Mechanical Properties on Ordinary Concrete, China Building Industry Press, Beijing, 2002

The main parameters affecting the quality of injection molding are: mold temperature, melt temperature, filling time, packing pressure (the percentage of filling pressure obtained from Moldflow), dwell time and cooling time.
Therefore, according to the design requirement and usage of the products, this article selects volume shrinkage variation, the average volume contraction rate[5], maximum settlement indicators, warping deformation as the indexes of product's size and shape accuracy, structure property, surface property and mechanical property.
Because this is a test with 5 levels and 6 factors, we can choose orthogonal table [6].
Table 2 Setting of variables and levels Levels Process Parameters Factors Mold temperature () Melt temperature () Filling time (s) Packing pressure (the percentage of filling pressure %) Pressure hold time(s) Cooling time (s) Level 1 50 240 0.4 110 4 4 Level 2 60 255 0.6 100 6 6 Level 3 70 270 0.8 90 8 8 Level 4 80 285 1.0 80 10 10 Level 5 90 300 1.2 70 12 12 In order to investigate how dose the number of samples affect the training and generation ability of BP neural network, another orthogonal test is taken, the level value of each parameters process is different from that of the first group, but the ranges of setting parameters are the same, setting of variables and levels is shown in table 3.
Two groups of orthogonal tests with six factors and five levels are taken in this paper, the one which has 50 groups of training samples is called multiple training samples.

Introduction Inevitably, the excavation of underground space will produce different degrees of destruction in soil, and ground deformation, especially for shallow tunnel, the large ground deformation will not only result in a tunnel accident, affected areas may also spread to the surface, resulting in surface subsidence and the destruction of surface structures and facilities, making impact and loss to the engineering[1][2].With high-grade highways gradually from the eastern to the western in recent years, the highway tunnel have a huge advantage to overcome terrain obstacles , and shorten the spatial distance in complexly geological background conditions in the western region[3].
Because of the complexity and diversity of the actual situation, even if it is the same construction methods also vary in a similar engineering background, in order to analyze the impact of the construction program works in the same background, also to reduce computation and meet the actual needs of the simulation, necessary to simplify the entire excavation, and focuses on the main factors in the process of simulation, surface displacement during tunnel excavation is the main object in this study.
Combining engineering geological investigation information with specification to ensure physico-mechanical properties of soil, advanced parameters according to [5]: increased physico-mechanical parameters of surrounding rock.
The physico-mechanical properties of initial support and secondary lining structure are calculated according to the equivalent section method described in [6].
Table 1 Physico-mechanical parameters of rock mass and supporting structure Material Severe γ (KN/m3) Elastic modulus E [MPa] Cohesion C [Pa] Internal friction angle φ/° Poisson's ratio v Silty clay 18.7 7.9 4.2×104 22 0.27 Advanced support 21 24.5 6.3×104 24 0.21 Primary support 25 2.8×104 4.2×106 53 0.2 Secondary lining 25 3.0×104 5.0×106 55 0.2 In the calculation, for shallow-buried tunnel, the calculation of initial stress field by weight.

Microporosity created during solidification affects strongly mechanical properties of AZ91 alloy.
The speed of heat removal inside the mould affects the refinement of the grain – higher speed of the heat removal makes the grain smaller. 5.
Mizera, Microstructural stability and creep properties of die casting Mg-4Al-4RE magnesium alloy, Materials Characterization 60 (2009) 1107-1113
Khomamizadeh, The effect of different content of Al, RE and Si element on the microstructure, mechanical and creep properties of Mg–Al alloys, Materials Science and Engineering A 523 (2009) 1-6 [7] A.
Shin, Effect of microporosity on the tensile properties of AZ91 magnesium alloy, Acta Materialia 55 (2007) 4293-4303 [9] H.

The parameter Kt is the orthotropic strength factor which is a function of the composite mechanical properties by the following expression:           lt l lt t l t G E E E K 2 21  (2) Where, El is the Longitudinal Elastic Modulus; Et is the Transversal Elastic Modulus; vlt is the Longitudinal Poisson Ratio; and Glt is the In-plane Shear Modulus.
These properties should be the ones for an orthotropic material.
Mechanical properties were measured according to ASTM D3039.
The measured physical and mechanical properties of the laminate are shown in Table 1.
Stiffness matrix calculus was made from mechanical properties announced in Table1, in order to have good accuracy in computational results.