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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].

To solve these problems, several authors have studied the influences of some experimental factors such as temperature and of mineral and organic additives on the workability and the setting properties of cements.
As a result, citric acid improves the setting times and mechanical properties of α-TCP bone cements.
Thereafter, we investigated the effect of citric acid concentration on mechanical properties and injectability, and developed a calcium phosphate cement with improved mechanical properties and injectability as a bone substitute.
Particle size is important for bone cement because it affects the properties of the dough stage, i.e., its viscosity and flow.
Results indicated that the concentration of citric acid in the liquid component influences both the mechanical properties and injectabilities of cements.

Introduction Among the factors that negatively affect the structural performance of polymer composite materials (PCM), the impact of moisture is especially prominent [1-10].
Antipov, Reversible influence of moisture on the mechanical properties of pcm after weathering, Trudy VIAM. 65 (2018) 110-118
Peng, Hygrothermal aging effects on the mechanical properties of 3D printed composites with different stacking sequence of continuous glass fiber layers, Polymer Testing. 100 (2021) 107-242
Gulyaev, The influence of climatic ageing on the properties of pcm-based epoxy resin systems, Trudy VIAM. 3 (2021) 128-136
Linul, Fiber-reinforced polymer composites: manufacturing, Properties, and Applications, Polymers. 11 (2019) 1667-1668

At the same time, the proportion of metal foam is only 0.1 ~ 0.6 times for the same volume of metal, the unit volume weight was only about 1/10 of the solid metal material, but also it has good shock absorption, noise elimination performance, and strong mechanical properties.
At the same time, the heat transfer coefficient of the metal foam heat sink is affected by its geometric size.
Fig.1 The comparison coefficient of heat transfer 4.2 The pressure drop In practical applications, the pressure and the fan power are usually the key factors in the cooling of electronics.
It shows that the yield factor of the heat sink decreases with the increase of the fan power.
Thermophysical Properties og high porosity metal foams[J].

The first function is to select the sensitive design variables by comparing the ratios of the mechanical performance sensitivities and mass sensitivity of the manipulator.
The sensitivities of some significant mechanical properties are performed for the design variables, which are listed in Table 1.
Thus the major variables which have an important influence on the mechanical properties and a relatively insignificant affect on the mass can be found.
Fig.5 Evolutionary history of the bending deflection in the design process Table 2 Optimization design results Mass[kg] bending deflection[mm] Equivalent stress[Mpa] Strain energy[mJ] Inherent frequency[Hz] Initial value 74.211 1.3139 20.007 44.281 130.47 Optimization result 67.464 0.6699 15.398 42.744 120.631 Comparing the optimization result listed in Table 2 can show that the mechanical properties of the manipulator are greatly improved; meanwhile, the mass is reduced to 67.464kg from 74.211kg in original, a decrease of 9.1% which realize the lightweight of the manipulator.
Through the mechanical testing of the inner-wall grinding robot in its actual working process, it can be detected that the manipulator is subjected to a load changing as sine wave with time.

These researchers studied the electrical and temperature properties of PV modules.
Analysis the influence of irradiance and ambient temperature on the performance of PV module The temperature of photovoltaic cells is affected by several environmental factors, such as irradiance, wind speed and ambient temperature.
The heat dissipation of the PV module is mainly affected by thermal radiation.
And when the wind speed increases from 0.5m/s to 10.5m/s, the temperature of PV module is not obviously affected by the wind speed.
However, when the irradiance reduces to 400w/m2, the wind speed will hardly affect the temperature of the PV module.

Introduction One of the main aims of modern mechanical engineering is a complex approach to providing high quality and competitiveness of an output which requires a close link between science and the manufacturing environment since absence of simple and safe ways to adjust processing becomes a key factor of labor intensity increase and quality worsening.
Final processing techniques using common abrasive tools in some cases do not allow achieving the required quality and operational characteristics of finished products since the use of productive instrument of superhard abrasive materials is limited due to problems related to restoration of their cutting properties.
Stabilization of the diamond grinding disk cutting properties is achieved by its extra electrochemical dressing.
At the same time, adjusting the electrochemical softening level of the material via changing the intensity of the etching current also affects the energy consumption in the combined electric powered diamond processing.
High performance and quality of hard-alloy materials processing are provided by stabilizing the cutting properties of metal-bonded abrasive tools and partial softening of the processed material.

It directly affects temperature-rise of the concrete and the variation in temperature stresses of mass concrete, to a certain degree, control occurring of the mass concrete cracks.
Introduction Cement hydration heat is the heat released by chemical reaction which happened when the cement is hydrating, and is a very important influence factor on thermal stress in the mass concrete construction.
Mechanics computation model of temperature field To find the effective method to control the temperature stress, several factors which influence the temperature field and stress field of mass concrete were analyzed by using the large finite analyzing software ANSYS.
Namely, don't consider properties of these materials change with time. 5) Select the appropriate unit on the basis of different elements type provided by ANSYS.
So we use unit SOLID70 in thermoanalysis firstly, and then use unit SOLID45 in structural analysis. 6)In the simulation process, involves the temperature field and stress field, i.e. thermal problems and mechanical problem.

At last, this paper adopted corresponding construction measure as per the uncertain factors.
As the slope stability affected directly to construction safety and the normal operation of the hydropower station, it is thought of a difficult and important issue.
Mechanic Property Analysis of Scaffold in High Slope Treatment Force Analysis of the Scaffold Permanent load: (dead weight of) scaffold poling, leger, log, bridging, lateral diagonal, fastener and safety net; dead weight of scaffold floor, railing, toe guard.
Variable load: drawing force which is produced by mechanical vibration is considered as 10KN. wind load： Wk=0.7μs·μz·Wo =0.7×1.0×0.8×3.12×0.2=0.35KN/m2
（1） Among the formula 0.7—reduced factor (temporality, maximal 5years, generally 3 years, ；W0—fundamental wind pressure， in XICANG W0=0.2KN/m2；μs—shape factor，μs=1.0φ；φ—wind protection factor of the scaffold； nearly getting φ=0.8；μz=3.12.

Kumamoto et al. stated that when a two-joint link mechanism was installed with an antagonistic pair of bi-articular actuators in addition to antagonistic pairs of mono-articular actuators, the two-joint link mechanism could demonstrates humanlike control properties at the endpoint [6].
Albeit that, if there is a model which correlates the PMA properties with the positional data, we might be able to control the orthosis mechanism precisely with co-contraction movement as well as simplifying the control algorithm and equations.
These factors also apply for the performance at the hip joint, which was able to achieve maximum muscle moment (flexion and extension) due to lack of actuation power when compared to mono-articular actuators alone and problems caused due to inertia.
Fujikawa, “Control properties of two joint link mechanism equipped with mono and bi-articular actuators”.
He, "Characterization of the dynamic properties of pneumatic muscle actuators".