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These uncertainties caused by the variety of structural materials used in the same monument, the difficulty of determining their mechanical properties and the random action and intensity of the earthquake phenomenon make essential the presentation of the vulnerability assessment presented in probabilistic terms.
Through this family of curves, it is possible to investigate the way that each factor affects the vulnerability of the structure, relatively to others.
The first one involves structural properties (i.e. material strength, dynamic properties) and the later one concerns the parameters characterizing the seismic event (i.e.
Using the results obtained, a classification of historical masonry structures is aimed, correlating their seismic response with their dynamic properties and applied earthquake parameters.
Usually, the values of those parameters aren't very accurate - they comprise instability and uncertainty due to the nature of these factors.

Yecong HE[8], based on the enthalpy model of phase change material wallboard room,the factors influencing the heat transfer performance of the wallboard were analyzed.
Fatty acid Temperature of phase change:20˚C-90˚C Melting heat is about the same as the paraffin's Better melting and solidifying properties, reversible melting and solidifying process, stable chemical property, no super-cooling, no phase separation, innocuous, cheap, small volume change as phase changing and large latent heat.
So it is much cheaper than the mechanical ventilation and the air conditioning related devices.
Moreover, it do not need any power and mechanical energy but a little If it adopts a automatic control system.
However the mechanical ventilation and the air conditioning system consume amount of power.

Numerical simulation of conical pick cutting coal and rock process based on ABAQUS* Chunsheng Liu1,a, Yang Song2,b and Chunping Ren3,c 1College of Mechanical Engineering, Heilongjiang University of Science and Technology, Harbin ,China 2College of Mechanical Engineering, Heilongjiang University of Science and Technology, Harbin ,China 3College of Mechanical Engineering, Heilongjiang University of Science and Technology, Harbin ,China aEmail:liu_chunsheng@163.com, bEmail:songyang0107@sina.com, cEmail:renchunpin@sina.com Key words: conical pick; three directional loads; ABAQUS/explicit; gradient; Pearson correlation coefficient Abstract.
Aimed at investigating efficient cutting method with a lower energy consumption, higher reliability and life, and researching the intrinsic relationships between ability of picks' breaking coal rock and related factors, this paper simulates the dynamic process of conical pick cutting coal rock by using ABAQUS/explicit, analyzes cutting load statistics, and evaluates the similarity of simulation results and test results quantitatively using Pearson correlation coefficient.
Considering the stress distribution that the pick broken coal and rock at different angle wedge, the use of the maximum tensile stress theory to establish the mathematical model of the conical pick cutting force[3],as shown in a formula (1),which reflects the relationship of the cutting force, geometry parameters(,), coal and rock properties (,,) and operating parameters()
The linear changes do not affect the results of the Pearson correlation coefficient, so that different units of data and value are also comparable.
One of the main reasons is defined in the simulation model of coal and rock is homogeneous, isotropic, without regard to properties that the bedding and joints of the coal and rock. 4 Conclusion The establishment of constitutive model of the extend linear Drucker-Prager plasticity, the failure criterion of coal rock that equivalent plastic strain and dissipated energy to simulate the dynamic process of crushing coal rock.

Despite the broad range of available flame retardants, the most promising direction of improvement the fire resistance is proper selection of disperse phases PCM in such a way that reduces the flammability and smoke formation while not affects other operational properties.
These factors can greatly influence the processes of pyrolysis of the filled polymer [21] and, consequently, the fire hazard of PCM.
It is also follows from Fig. 4 that nature of the dependence between 100/LOI and many control factors related to amount of filler is linear.
Evaluating the Influence of Varied Fire-retardant Surface Coatings on Post-Heat Flexural Properties of Glass/Epoxy Composites.
Preparation and Properties of a Single Molecule Intumescent Flame Retardant.

Aim at the high-resolution space telescope experience characteristics of the environment, we should select specific stiffness and strength materials for mechanical structure of telescope to ensure that the properties of mechanical.
Table 1 show the basic physical property of materials that commonly used for space telescope.
Table1 Basic physical property of materials that commonly used for space telescope Materials Density kg/m3 Elastic Mod GPa Poison Ratio Thermal Cond W/m·K Expan.Coeff (10－6/℃) Ly12 2800 73 0.33 126.1 22.9 TC4 4430 109 0.34 5.44 8.8 4J32 8140 145 0.23 13.3 0.05～1 Zerodur 2530 91 0.24 1.64 0.05 ULE 2210 67 0.17 1.31 0.03 SiC 3200 400 0.18 155 2.4 According to the data given in Table1, compare the mechanical and thermal property, machining property and economic factor of materials.
Especially in the orbit state, the shape of primary mirror assemblies will change due to the case of the space environment temperature change, these changes will affect imaging quality of the optical system.
Opto-Mechanical System Design[M].

Recently emerged two-dimensional (2D) materials possess distinctive and uncommon properties such as changeable bandgap, layer-dependent mobility, high aspect ratio, quantum confinement due to atomically thin layer [5, 6].
It has the properties of high absorption coefficient, good thermal conductivity, ultrafast photo-response, exceptional carrier mobility, wide absorption range (ultraviolet to infrared), and layer-dependent transparency [12].
The choice of semiconductor material for the solar cell application depends on its properties like bandgap, effective mass, doping level, and fabrication facility.
Simulation Results The photovoltaic properties of our proposed structure have been simulated to assess its performance under light illumination and do further optimization.
Conclusion A numerical method such as NEGF has distinct advantages to calculate and predict the outcome of any emerging devices such as photovoltaic properties of a solar cell at nanoscale dimension.

Its stress significantly affects reliability and performance of high pressure and large power RMP.
So in order to ensure safety of the equipment, the larger safety factor is adopted.
Table 2 is crankshaft material properties.
Study on the Dynamic Load and Mechanical Property of the Plunger Pump Crankshaft[J].Machinery Design & Manufacture, 2007(5):155~157
Chinese Journal of Mechanical Engineering, 2008, 44(10):272~276

Mechanical Properties and Biocompatibility of Porous Titanium Prepared by Powder Sintering Ik-Hyun Oh 1,a, Hyeon-Taek Son 1,b Chang-Seok Kang1,c , Jae-Seol Lee1,d , Jae-Ik Cho 1,e, Jung-Chan Bae1,f, Byong-Taek Lee2,g and Ho-Yeon Song3,h 1 Gwangju Research Center, Korea Institute of Industrial Technology (KITECH), Gwangju, 506-824, South Korea 2 School of Advanced Materials Engineering, Kongju National University, Chungnam, 314-701, South Korea 3 Department of Microbiology , Soonchunhyang University, Cheonan-city, 366-1, South Korea a ihoh@kitech.re.kr, bsht50@kitech.re.kr, ccskang7@kitech.re.kr, d jslee7@kitech.re.kr, e uwjaeik@kitech.re.kr, fjcbae@kitech.re.kr, glbt@kongju.ac.kr, and h songmic@sch.ac.kr Keywords: porous titanium, spark plasma sintering, porosity, young's modulus, biocompatibility Abstract.
The purpose of this study is to fabricate porous Ti compacts having roughened surface and to control the properties such as porosity and Young's modulus.
In contrast, sintering temperature affects very slightly the densification of Ti compacts, as can be seen in sintering at each temperature without sintering pressure in Table 1.
Sintering temperature (�) Sintering pressure(MPa) Mean powder size(µm) Porosity (Vol. %) 900 0 425 39.2 218 35.9 94 33.1 10 425 19.3 218 9.3 94 5.1 1100 0 425 37.7 218 34.9 94 31.9 1300 0 425 34.2 218 30.9 94 24.1 Consequently, the initial powder size and sintering pressure are dominant factors governing the densification behavior of porous Ti compacts in the temperature range from 900 to 1300�. � It should be noted that the present compacts with the porosities greater than 20 vol% are promising for biomedical applications, since the optimal porosity of implant materials for ingrowths of newbone tissue is in the range 20-50 vol% [7].

The noble alloys show a good biocompatibility, but the mechanical properties are low, and the thermal expansion coefficient is higher compared to ceramics.
However the superior mechanical properties and the low cost have made these alloys to be the most used at this time in our country for the metal frame of implant-supported prosthesis.
Zirconia is widely used to build prosthetic devices because of its good chemical properties, dimensional stability, high mechanical strength, toughness, and a Young's modulus (210 GPa) similar to that of stainless steel alloy (193 GPa).
This can cause distortion of the metal structure affecting its passive adaptation.
The appearance of restoration after the test into oral cavity and after finishing and polishing The diacrylic composites resins (DCR) tend to impose themselves in the manufacturing of prosthesis and replace acrylic resins in a series of prosthetic devices, due to a number of favorable properties, such as chemical bonding of the DRC to the metal that prevents leakage of the fluid from the oral cavity, increased resistance to abrasion, resistance to aggressive factors from the oral environment.

Firstly, a program was developed in finite element model to simulate actual mechanical behavior of vehicle at urban intersection, based on dynamic features of variable speed moving vehicle loads.
Uniform moving: The speed of uniform moving will be affected by the following factors: length of every load l, load time t0, thus the final speed can be expressed by:
(4) Material Properties The material parameters used in the simulation are shown in Table 1, which are common for many dense graded HMA in China.
Material properties used in finite element simulations Properties Upper asphalt layer Middle asphalt layer Lower asphalt layer Upper base layer Lower base layer Subgrade Material SMA-16 AC-25 AC-30 LFAS soil-lime e - Thickness[m] 0.04 0.05 0.07 0.38 0.36 5 Elastic modulus[Mpa] 1200 1100 1000 1200 400 40 Poisson’s ratio 0.35 0.35 0.35 0.3 0.35 0.4 Solid bulk density [kg/m3] 2500 2500 2500 2100 1900 1900 damping coefficient β 0.05 0.05 0.05 0.05 0.05 0.05 Mechanics Responses Analysis Distribution of vertical displacement (a) Accelerating (b) Decelerating (c) Uniform moving (d) Time history Fig.2 Distribution of vertical displacement From the figures, it is shown that vertical displacement of pavement during starting and braking is larger than that under constant motion.
[4] X.D.Hu: Measurement of tire pressure distribution and mechanical response analysis of asphalt pavement, Tongji University (2003).