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Introduction When a soil specimen is sheared in an axisymmetric triaxial compression test, its mechanical and material behaviors are affected by multiple factors, i.e., material properties of the soil, confining pressures, initial void ratios, and etc.
However, it would take huge amount of time and efforts to investigate these factors if using laboratory tests.
For soils, especially sands and gravels, the size of particles affects not only mechanical behaviors (i.e., stress-strain response) but also material behaviors (i.e., permeability, void ratio, tortuosity, etc.).
The initial moduli for all three specimens are almost the same, which proves that they were not affected by particle sizes.
For real soils, particle breakage will affect the results substantially.

Research on the Construction of Three Levels of Customization Model Based on Human Engineering Weijin An1,a and Wenming Yang2,b 1School of Mechanical Engineering, Tianjin University, Tianjin 300072, China 2School of Management, Tianjin University, Tianjin 300072, China aanweijin@tju.edu.cn, bWyang@tju.edu.cn Keywords: Human engineering, Individual needs, Three levels of customization model, Man-machine system Abstract: In order to satisfy increasing demand for personalized products, through analysis characteristic parameters of individual factors such as the various parts of the body size, body weight, body surface area, factors affecting the performance of the machine and their mathematical relationships, three levels of customization model based on human engineering by using mechanics and control theory was established to help designers to design personalized products, best meet customer's all aspects of demand.
Although ergonomics reveals the laws of man-machine relationship, but the provided data are average data, in real life, people under the influence of different factors such as the sex, age, hobbies, alone "scientific data" can not fully solve the practical problems.
The model consider not only the law of human activities, but also impact of individual factors on the static and dynamic performance.
Customization process is from the shallower to the deeper: First, according to the needs of consumers to choose the colors and models; Second, according to the individual size input by customer to design the structure of various components, for example, the design of the frame; Third, according to weight and size to design the size of the various components which affect static and dynamic properties, such as: spring.
To determine custom parameter, designers need to consider bicycle structural elements, human-vehicle dynamics feature and human factors [8-9]: 1.

The used titanium alloy in the experiment is widely used for manufacturing the aircraft components, and the material trademark is TA15, of which the main composition and mechanical properties is shown in table 1 and table 2 respectively [6].
Because milling force can not only influence the machining accuracy and surface quality of the parts, but also directly affect the quantity of heat generated, and further affect the tool wear, tool breakage and tool life etc. [9], according to the reference [10], there are many factors which can affect milling force.
But when the tool, cooling and the material are specified, the milling depth, milling width, feed engagement and milling speed will be the main factors to affect milling force.
Because of many factors to affect milling force, the method of orthogonal experiments is used in the test.
The dosage level of main influence factors is shown in table 3.

Introduction 1-3 piezoelectric ceramic/polymer composites have been considered to be efficient and powerful materials for ultrasonic transducers because of their better dynamic properties than monolithic PZT [1,2], such as higher thickness electromechanical coupling constant kt, lower mechanical quality factor Qm and acoustic impedance Z.
These dynamic properties of 1-3 composites are deeply dependent on the mechanical properties such as the velocity and attenuation of ultrasonic waves in epoxy, which are determined by the resonance characteristic [3].
Lower acoustic impedance Z of 4-9 Mrayl is well matched to that of the load to minimize reflection losses at the interface; The acoustic impedance matching well at the interface determines lower mechanical quality factor Qm (wide bandwidth).
However, the thickness of the 1-3 composite is an important factor affecting the resonance characteristic, as proved by the following experimental results.
Conclusion 1-3 PZT/epoxy matrix composites hold better dynamic properties than pure PZT ceramics: higher electromechanical coupling coefficient kt of 52-65%, lower acoustic impedance of 4-9 Mrayl and lower mechanical quality factor Qm of 4-9.

The mechanical properties of the specimens were evaluated by means of tensile and impact tests.
Take the average of three tests of each mechanical properties value as the experimental results.
Fig. 1 The heat treatment process of tested steel Results and Discussion Mechanical Properties.
The existence of chain and network of precipitates is just one of the factors to reduce the toughness and tensile strength of material.
Increasing deformation ratio has improved the precipitates morphology and mechanical properties.

From the experiment results, it was found that the cutting direction was an important factor affected to the bent-up angle and cutting load response of the nylon film.
In the laminated material cutting, problems that affect the product quality of the cutting worksheet are caused by many mechanical conditions for making the cutting process such as the tip thickness, mechanical properties of underlay.
Moreover, the mechanical combination between the cutting tip and cutting sheet is played important factors, especially the mechanical properties of the laminated sheet is the primary factor.
Due to the different material properties of these layers, troubles sometimes occurs with unstable cutting phenomena.
Mechanical properties of polycarbonate underlay and nylon film.

The properties of polymer/OMMT nanocomposites were investigated.
The impact factors of OMMT with different layer spacing on the morphology of polymer-based nano-composites were studied.
Mechanical properties: Tensile stress and tensile modulus were measured according to standard ISO1184-1983 by using an electronic tensile tester.
Properties of PA6/OMMT Composite, J.
Structure and properties of nitrile rubber/polyvinyl chloride/organic montmorillonite nanocomposites prepared by mechanical blending, J.

This paper presents a 2-D thermo-mechanical (TM) model of a 2-D MOSFET half-cell for assessing the TM stress in the gate-source insulating layer during SC including the phase change behavior and the temperature-dependent properties of the source metallization.
The layer of gate-source insulation marked as PMD oxide in Fig. 1 is implemented in COMSOL by using constant material properties of silicon dioxide (SiO2) due to a lack of knowledge on the material properties of the actual pre-metal dielectric (PMD) layers.
Therefore, the second study is run with dM,Cu = 4 µm using the copper material properties provided by COMSOL and from [15] for the source metallization material.
Summary The aim of the presented work is to show how the thickness and material properties of the source metallization can affect the thermo-mechanical stress in the gate-source insulating layer and to correlate the simulation results to the failures of SiC power MOSFETs observed in the short-circuit experiments.
Accordingly, the developed modelling approach represents a baseline for evaluating how different material properties can affect potential failures of SiC power MOSFETs at very high internal device temperature.

The importance of the use of partial safety factors of FRP and concrete in the reliability design of concrete filled FRP tube columns is studied.
Numerous investigations have been conducted on the mechanical performances of FRP confined concrete columns.
The statistical properties of the model error are given in Table 1 [2].
Table 1 Properties of the strength model error d m s COV Distribution Eq.(2) 1.07 0.22 0.21 Lognormal Note that m=average value; s=standard derivation; COV =coefficient of variation.
However, under a relative high confinement ratio (i.e., Rf =1.9), the FRP partial safety factor is no longer affected by the variation of concrete strength but will be in a high level.

The influence of conditions on the properties of PVFM foam, such as mechanical properties, water absorption, pore structure and bulk density, is well discussed individually.
It has been shown that both the reactant and acid catalyst affect the degree and speed of acetalization, therefore the mechanical properties, pores continuity and water absorption of the resultant sample.
Since a lot of factors such as agitating speed, reaction temperature would influence the foaming performance of PVF, all the reaction conditions are carefully controlled.
However, the WA peak appears in the sample prepared with 4 g SLS, so do the mechanical properties.
A. water absorption properties B. mechanical properties Fig. 5.