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As the typical of morden ground fissure in our country, there has been already more than 400 ground fissures found in Fenwei Basin, making it be one of the most developed ground fissure disaster areas in our country[2], and seriously affects the city's construction and development of national economy.
In recent years, because of the human water-related activities, underground energy resources exploitment, human engineering activities seismic effect and other uncertain factors, ground fissure disasters are becoming more and more serious.
But the dynamic characteristics of ground fissure research fields, such as ground seismic amplification effect of the ground fissures, has been less stepped into, and in this weak links of the ground fissures, the achievement is few and there is no consolidated understanding on the selection of the parameter of ground dynamic properties.
In this model, the soil was treated as a visco-elasticity body and the equivalent shear modulusand equivalent damping ratios are employed to reflect the nonlinearity and hysteresis of the dynamic soil stress-strain relationship, and the backbone curve express the relationship between the maximum shear stress and the maximum shear strain, which reflects the nonlinearity of the dynamic stress-strain relationship .As for hysteretic curve, it expresses the relationship between shear stress and shear strain within a certain stress cycle of each moment, at the same time, reflects the dynamic stress of dynamic strain hysteresis. 3 Experimental schemes Taken from Chang'an ground fissures footwall of Xi'an metro line 4, the test loess are 12~12.5m in depth and 6m far away from ground fissures in horizontal direction, the basic physical and mechanical properties are shown in table 1.
Table 1 Physical and mechanical properties of the sample Natural density ρ[g∕cm3] proportion Gs Plastic limit wp[%] Liquid limit wl[%] Void ratio e0 1.800 2.71 19.4 32.3 17.15 Testing on STD-10 vibration triaxial test system, soil samples are cylindrical specimens of 39.1 mm in diameter and 80 mm in height.

Fig.1 Contour and thickness distribution of Fig. 2 Grid of model of violin front and back plate sounding box The Material Properties of Violin Sounding Box.
In finite element analysis, material properties have great impact on the results of simulation.
In this paper, mechanical performance parameters of spruce and maple are adopted from literature [8], they are shown in Table1.
Table 1 Material properties of violin sounding box applied in finite element method material Density (kg/m3) Young modulus (MPa) Shear modulus (MPa) Poisson's ratio X Y Z XY YZ XZ XY YZ XZ maple spruce 540 410 12430 7590 833 592 1740 326.4 920 463 311 486 1106 22.8 0.509 0.245 0.354 0.372 0.434 0.467 Modal Analysis of Violin Sounding Box.
In order to study the factors that influence the vibration of violin sounding box, this paper selects different front plates in Table 2 to make up violin sounding box.

But, thanks to its unique technical and operational properties, the plate has become more widely used.
Such unique properties and a wide range of applications attract special attention from scientists and operators from different countries who strive to constantly improve the characteristics of airfield slabs. 2 Literature Review and Problem Statement To study the load-bearing capacity and crack resistance of airfield slabs, different approaches are used [1].
Operation of airfield slabs under climatic factors and significant loads from modern types of equipment leads to surface wear and the formation of various defects, primarily cracks.
Blacha, P.Iwanowski, Analysis of load bearing capacity of cement concrete airfield pavement's construction in relation to its' changes of physico-mechanical parameters.
Kovalenko, Determination of the influence of deflections in the thickness of a composite material on its physical and mechanical properties with a local damage to its wholeness.

Introduction Most Ni-based superalloys are strengthened by the precipitation of coherent γ' precipitate, and the size and volume fraction of the γ' phase are optimized to get the desired properties.
However, since these practical superalloys are multi-component alloys other precipitates such as σ and η phases are also formed and affect the morphology of microstructure and the mechanical properties.
Therefore, the precipitation behaviour and the microstructural morphology of the coherent phases are a little complex and it is not easy to elucidate the effect of coherent phases to the whole precipitation behaviour and the mechanical properties.
The absorption effect of X-ray inside the foil was corrected by the extrapolation method [5] and their chemical compositions were estimated with the so-called Cliff-Lorimer factors [6] evaluated from the reference specimens.

It is known that the vapor produced from the evaporator moves in a cycle to generate mechanical power that will be transformed into electricity.
Fluid fouling is one of the factors affecting heat transfer due to the deposition of undesirable mineral substances on the wall of heat exchangers.
More specifically, poor flow distribution, plate length and sudden flow expansion are all factors that decrease the performance of plate heat exchangers.
Mostly, the establishment of these types of equations aims to study the coupled flow-heat transfer in the evaporators and to identify the forces affecting the flow and therefore the performance of the heat transfer.
Zhang, Synergistic enhancing effect of tungsten-copper coated graphite flakes and aluminum nitride nanoparticles on microstructure, mechanical and thermal properties of copper matrix composites, Materials Science and Engineering: A. 857 (2022) 143987

The effectiveness of envelope thermal properties affects the heating and cooling loads directly, therefore, it is important to select suitable technologies to improve the envelope thermal properties, making buildings more comfortable and reducing utilization of auxiliaryenergy consumption equipments by reducing the amount of heat escaping in winter and entering in summer.
Beijing: China Architecture and Building Press. 2011. ].Besides, Composite Light-weight (CL) building system, finish materials, and pasting insulation panels (such as expansion perlite panels, expanded polystyrene, extruded polystyrene panels, etc.), inside external walls are widely used technologies. 2.2 Doors and windows The thermal performance of windows has been considered the worst among all the envelope components, and has been one of the main factors influencing indoor thermal environment quality and building energy consumption.
Energy saving technologies of building services and equipment Building energy consumption, which is expressed in the form of electricity and fuel energy consumed by different facilities, and facilities conversion efficiency directly affects the fuel and electricity consumption.
For example, intermittent heating and cooling, selection of heating radiator and priority selection of natural ventilation to mechanical ventilation, etc. are the important considerations in the HVAC system design process[[] The Leadership Institute of Ministry of Construction.Practical engineering technologies in building energy efficiency.Beijing: China Electric Power Press.2008. ].

Similarly, other problems may be very sensitive to inaccurate assumptions in material properties, loading, geometrical idealisations etc.
In practice, however, the sub-modelling approach cannot be used in cases where the local non-linear response of the sub-model, not included in the global model, even mildly affects the global model response, as for tubular frameworks.
Using SK tm ==1σ (3) y LP P S σ= (4) y L m P P σ σ =∞= (5) where Kt and S are the elastic stress concentration factor and nominal stress, respectively, P is the load applied to the structure and PL is the structure limit load for elastic-perfectly-plastic material behaviour with a yield stress σy. σy/PL is independent of the material properties and depends only on the geometry and loading mode.
mB E σ σ ε += (7) This has been extended to multiaxial states as follows: SK m tq mq       −+= )1( 1 1σ (8) where Ktq is an "equivalent stress" concentration factor and qσ is the peak equivalent stress.
For dynamic or time-dependent studies, where non-linear behaviour, e.g. of connections, may affect structural damping or stiffness, or fatigue damage accumulation, the ability to incorporate such non-linearities into simplified global models is clearly important.

Similar to LED substrates, the near lattice-match to GaN and the high thermal conductivity are key properties [2].
It is suspected that this is a measurement artifact due to changes in external factors affecting the measurement unit (e.g., temperature fluctuations in the laboratory).
Wellmann, Impact of Mechanical Stress and Nitrogen Doping on the Defect Distribution in the Initial Stage of the 4H-SiC PVT Growth Process, Materials 15.5 (2022): 1897
Nakashima, et al., Raman scattering study of carrier-transport and phonon properties of 4H− SiC crystals with graded doping, Physical Review B 76.24 (2007): 245208.

Many of the coating properties, such as hardness, adhesion, tribological behaviour or formation of micro cracks, depend not only on the material inherit properties, but also on the thermal history of the component.
Table 2: Mechanical and thermo physical properties of substrate and coating materials (b: bulk material; APS: sprayed material) [24].
The thermal history of the composite influences coating properties such as porosity, residual stresses, micro crack formation, etc.
By applying air cooling, the crack formation was reduced and controlled, being the porosity the parameter affecting the coating electrical resistivity, as it can be seen in Fig. 18.
However, if the requirements regarding electrical properties are fulfilled by the one-layer systems, these are less time consuming during production.

Mechanical properties of 34CrMo steel obtained during testing with different deformation rates in solution Nace NACE TM 0177 (A).
A Air Sol.A/ Air Air 0.0013 1037 1037 1 20.5 20.5 1 Solution А 0.13 1012 1037 0.98 14.7 20.5 0.72 Solution А 0.013 993 1037 0.96 6.3 20.5 0.31 Solution А 0.0013 556 1037 0.54 3.7 20.5 0.18 Solution А 0.00013 552 1037 0.53 3.5 20.5 0.17 Tests in solution A with gas saturation with hydrogen sulfide showed a significant effect of the deformation rate on the mechanical properties of 34CrMo steel.
A further decrease in the deformation rate to ⁓ 10-7 s-1 practically does not affect the values of the obtained fracture characteristics.
When the temperature rises to 80 °C, the stress ratio increases almost twice, which indicates a significant decrease in the negative factor of hydrogen sulfide.
Steel 09Mn2Si is the least affected by temperature on destruction in the hydrogen sulfide environment compared to steels 34CrMo and X70, which is confirmed by the stability of the criterion with a deformation ratio of 0.17 despite temperature changes.