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Structural optimization is the process of such a design which fulfils all requirements and simultaneously minimizes weight or other efficiency decreasing factors.
Optimization methods The structural optimization is a design process which fulfils all strength, stiffness and fatigue requirements, and minimizes weight or other efficiency decreasing factors.
Optimum design There are several parameters which directly affect the convergence of optimization.
The criterion CONV1 controls a relative difference in the objective function and the criterion CONVPR derives a limit for the maximum of relative property changes.
These two management parameters affect length of the optimization process.

And the experimental data of the pushed method are free from the influence of random factors.
Quantitative characterization and evaluation of coating-interface bonding properties of substrate material has always been the difficult problem in the surface-engineering technology research.
So far, a quantitative test method used for high performance coating adhesive strength of combining has not yet obtained, data dispersion small, influencing factors few, characterization parameters simple but physical meanings clear.
In order to solve this problem, the pressure-pushing is put forward in this paper, which is not affected by viscose bond strength limit.
Comparing the results of these two methods, the averages are equal results on the same coating materials, of which the deviations are among the random factors’ scope.

The main impact factors of Pinghai Bridge structural durability Chloride corrosion.
The main ways and design ideas sea of improving the durability of cross-sea engineering structures The main affecting factors of the durability include the structural design, material properties, construction quality, maintenance, operation and maintenance of components.
To improve the durability of reinforced concrete structures, we can start from the following main influencing factors.
At the same time advances and improvements of the research on concrete admixtures to improve durability are got for the high-performance concrete has lower cost and can improve various physical and mechanical properties of concrete.
The durability factors mainly considered is the reinforcement corrosion, alkali-aggregate reaction and thermal stress cracks due to chloride ion penetration.

Limit Load Finite Element Analysis of Thick-walled Cylinders with Surface Cracks Under Combined Internal Pressure and Axial Tension Mahdi Maarefdoust1,a, Pooria Akbarzade2,b 1 Islamic Azad University, Gonabad branch, Mechanical Engineering Department, Gonabad, Iran. 2Phd Student, Ferdowsi University of Mashhad, Mashhad, Iran.
Moreover the potential impact of environmental assisted or accidental damage that result in creation of surface defects and consequently affects the ability of vessel to withstand the applied loading conditions.
Introduction The limit load value is one of the most important inputs when an R6 (2007) type structural integrity assessment is performed for a defective cylinder as it directly affects the results of both fracture and plastic collapse assessment.
The material properties used in all analysis are Young’s modulus, E=212GPa, Poisson’s ratio, v=0.294, yield stress, σy=370MPa and ultimate strength, σut=644MPa.
Normalized limit load values for cylinders with axial crack, material hardening Conclusion As said before, limit load values are one of the most important factors in designing and integrity assessment of transmission pipelines and pressure vessels.

If there is a certain relationship between any one of the factors and another factor, then and are related or associated.
The Engineering development stage qualitative correlation between the influencing factors.
Maintainability of the factors affecting the relationship has a different scope and intensity.
Maintenance of the expression of the impact of factors associated with the matrix.
On the contrary, it just shows up and disassembly, and other factors, the strength of association is relatively large, the identification mark, and environmental factors and other factors associated with strength, when the score of other factors unchanged, improved two factors will lead to system maintenance has been greatly improved.

Sliding-Mode Fuzzy Control Using in a Double-Axial Pump-Controlled Folding Machine Ray-Hwa Wong1,a 1 Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taiwan, R.
O C. 1 Department of Mechanical Engineering, Hwa Hsia Institute of Technology, Taiwan, R.
Mp represents plant and ζ is the weighting factor of control voltage correction.
improved in time via adaption gain and get better tracking properties.
The velocity change is a key factor to affect and e .

Introduction Every construction is affected by number of negative factors, which are for example impacts of snow, wind or freeze, but the most significant influence on buildings usually has wetness.
Wetness in masonry used to be manually decreased only by mechanical methods in the past.
Range of the most commonly used building material was chosen in order to determine properties of each hydro-isolating gel.
For testing properties of injection gels and building materials were chosen various laboratory methods in order to thoroughly describe their properties.
[3] ČSN 73 1357: Determination of capillary properties of aerated concrete.

Mohamed1 1Dept. of Mechanical & Materials Engineering, Faculty of Engineering & Built-Environment, Universiti Kebangsaan Malaysia, Bangi, 43600 Selangor, Malaysia 2Dept. of Mechanical Engineering, Politeknik Kota Kinabalu, Sabah, Malaysia aakbar.othman@gmail.com Keywords: square composite tube, quasi-static, axial loading, absorbed energy Abstract.
Results showed that the tube’s energy absorption capability was affected significantly by varying of different type of composite in terms of composite fabrication and variable aspect of cross-section.
Crushing during internal energy is one of the significant factors in their application in applied vehicle crush structures [1].
Besides that of composite material they also serve other multiple advantages such as excellent in mechanical and physical properties of strength, durability, weight reduction and hence lower fuel consumption.

The equation of thermal convection: （2） The factors affecting formula of thermal radiation can also be written as: （3） The entire heat dissipation formula can be attained by the formula (2) (3): （4） The heat flow is proportional to the coefficient of convective heat transfer and the heat dissipation area.
This shows that substrate thickness affects the utilization efficiency of fins.
Compared with the heat conduction, heat dissipation is the major factor.
Electro-mechanical engineering, (2004), 20(4) [2] Sun zheran.
Effects of Different Package Structures on Thermal Properties of High Power White LED Key Engineering Materials,(2012),503:65-70 [3] Galvis.E.

The reliability of electrical connectors is affected by the external environment stresses.
High temperature is one of the main factors to cause the failure of electrical connectors.
The impact of high temperature on the reliability of electrical connectors mainly includes:1) to accelerate the aging of insulator, resulting in the deterioration of electrical insulation; 2) to accelerate the deterioration of the mechanical properties of the elastic material, resulting in the stress relaxation and destruction of the coating of contacts; 3) to accelerate the oxidation of contact material and exacerbate the formation of surface film, therefore, to affect the reliability of contact; 4) to cause the changes of assembly relations between metal and non metal parts, and the extra stress due to the thermal deformation, which is probably the potential failure factors [4].
The followings are the fundamental factors concerning the test.
The length of test time not only affects the cost and efficiency, but also affects the authenticity of test results.