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Introduction During the process of hot rolled steel plates, the control of austenite grain size plays an important role in microstructure optimization and property improvement.
This must influence the mechanical properties of hot rolled steel plates [1].
Especially in thermomechanically controlled process, the amount of deformation, deformation temperature, strain rate and interrupted time are important factors to affect the austenite grain size.
Severe plastic deformation, i.e. higher amount of deformation, is also a key factor to refine austenite grain size, even to refine final microstructures.
All the compression tests were carried out using a thermo- mechanical simulator.

Figure 1.The Plate Rolling Equipment Diagram This process not only improved the property of production, but also reduced yield losses of the rolling mills.
Cross rolling can be affected by the time of the billets and staying temperature, and the length of the awaiting temperature of plates, the finish rolling and each section of rollers in different rolling stages and other factors.
The Optimal Allocation Plate Model and Algorithm The optimal allocation Plate Model Rolling quality optimized model:Suppose that is a date vector for each attribute of the plate after rolling (such as thickness, width, toughness, ductility, briquettability, mechanical properties and so on). , is the th attribute,, is the total of attributes.
(2) Mutation operation: Mutation operation is the key step in the differential evolution, defined as (2) Where, is randomly selected from the current population, ,andare individuals randomly , selected from the population.is a zoom factor
Research on Product Configuration Optimization Based on Multi-object Genetic Algorithm [J], China Mechanical Engineering, 2004, 15 (20):1819-1875

However, if the more rolls are located near the rear stands, the more the surface quality of the hot strip products is affected by their surface morphology.
Discussion As described in the introduction above, hot rolling properties are greatly influenced by various microstructural factors such as: (1) kind, shape, volume fraction, and distribution of carbides and graphite; (2) characteristics of matrix; and (3) solidified cell structure.
In summary, these microstructural factors should be systematically controlled to optimize the all related mechanical properties, when manufacturing CRIC rolls with excellent rolling performances.
The report [10] revealed that, some of V can be dissolved in the matrix, so it strongly affects the formation of graphite due to its relatively high affinity with carbon.
The number of the NbC carbides is increased by increasing the Nb contents, but if Nb contents exceed eutectic line PQ, there will be a density-induced NbC segregation zone which appears at the outer region of the section. 3) The roll-4 seems to be reasonable in terms of correlation between microstructure and rolling performance, but it needs to increase the spherical graphite by 3~5% through suitable adjustment of microstructural factors.

However, for the present, current study mostly focused on mechanical structure.
Table 1 Comparison of Subsurface Detection Technology Detection Methods Principle Advantage Defect Schematic Diagram GPR Dielectric properties, Electro-conductivity High precision, Wide range of application High-frequency signal attenuated severely, Accuracy is obviously influenced by antenna size.
The robot must not only detect voids, water, life forms in the soil, but also identify rocks, walls and other distractors.GPR can complete the detection of above objects, according to different dielectric properties.
Due to space restrictions in the exploration and rescue, volume become an important factor that affect the applications of subsurface drilling robot.
The power and stability of pulse source directly affect the detection range and accuracy of GPR.

This article introduces two kinds of frame structure system structure for steel structure and reinforced concrete structure, analyzes the similarities and differences in the structural properties, structural occupied area, time limit for a project, project cost and comprehensive economic benefits and other aspects.
Reinforced concrete structure makes reasonable use of two kinds of material mechanical properties for reinforcing steel bar and concrete, this application has a history of nearly 200 years [1-4].
Using different structural materials, the upper structure construction period has a greater impact, but also suffers from the influence of environmental and construction season, geological conditions and many other factors.
Moreover, structural material also affects on external wall maintenance cost, but the external costs of maintenance structure is considered to impact of overall cost in this project.
Conclusions This article introduces two kinds of frame structure system structure for steel structure and reinforced concrete structure, analyzes the similarities and differences in the structural properties, structural occupied area, time limit for a project, project cost and comprehensive economic benefits and other aspects.

Influence of the Source and Sink Temperatures on the Experimental Research of a CO2 Trans-critical Refrigeration and Heat Pump System ZHANG Wen-hui1,a, WANG Zhe*1,a, GONG Yi, WU Xue-hong, LU Yan-li *1Department of Electrical and Mechanical Engineering, Refrigeration and Cryogenic Center, Zhengzhou University of Light Industry, Henan, Zhengzhou, No. 5 Dongfeng Road, 450002, P.R.China *ae-mail: zhezhenature@gmail.com Keywords: The source temperatures, The sink temperatures, CO2 trans-critical cycle, Heat pump, Refrigeration, Experimental study Abstract: The performance of the CO2 trans-critical system is affected significantly not only by optimal system pressure but also by instantaneous ambient temperatures.
It is a natural refrigerant, non-toxic, odorless, non-flammable, environmentally friendly and excellent thermal properties, known as "a nearly ideal refrigerant" [3].
The CO2 enter the intermediate heat exchanger is not a high temperature and pressure of liquid but the mixture of liquid and supercritical fluid, which will affect the trans-critical CO2 refrigeration cycle performance.
Experimental Determination and Analysis Thermodynamic analysis of the system, the energy efficiency of trans-critical CO2 refrigeration and heat pump system by the gas cooler outlet temperature, pressure and other factors [9-10], which variables are relatively independent in the supercritical region, so the design for the experimental independent variables.
This is because the heat source temperature affects the water in the evaporator inlet temperature, the temperature of the water circulation system as a whole rise and the temperature trend.

Microstructure and Creep Properties of Silicon- and/or Germanium-Bearing Near-α Titanium alloys T.
The effects of Si and/or Ge addition on the microstructure and creep properties at 650°C and 137 MPa were investigated in near-a Ti–Al–Sn–Zr–Mo alloys.
The present authors previously demonstrated the effects of Ge addition on the mechanical properties of a near-a alloy [2].
In the present study, the effect of Si and/or Ge addition on the creep properties of a near-a titanium alloy was investigated at 650°C.
The addition of 4.1 wt% Ge to the near-a titanium alloy changed the structure of the a/b interface; this can be a strengthening factor.

Then the density of target material is one of the most important factors [15].
To improve the optical and electrical properties of the sputtering film, target usually requires a high density.
The density of target not only affected the sputtering rate, but also affected the electrical properties of the film.
Zhao, Structural, Electrical and Optical Properties of p-Type Transparent Conducting SnO2:Zn Film .
[19] Dawar AL, Joshi JC, Review Semiconducting Transparent Thin Films: Their Properties and Applications.

Because the texture and mechanical property of dissimilar steel welded joint is non-uniform, the joint is the most unsubstantial segment in welded units.
In addition, the mechanical property of steel and copper welded joint has also been researched [8-11].
Therefore, the refined mesh must be used in the region of heat affect zone and near welding line.
That is because the difference of linear expansion factor and the thermal conduction coefficient is between 20 steel and Cr5Mo steel.
Lu, et al: China Mechanical Engineering Vol. 11 (2000), p. 732-734

Creep modeling for Concrete Filled Steel Tubular members compressed with a large eccentricity Han Bing1, a, Wang Qian1, Wang Yuan-feng1, 1School of Civil Engineering, Beijing Jiaotong University Beijing 100044 aemail: bhan@bjtu.edu.cn Keywords: concrete-filled steel tubes; creep; large eccentricity; model B3 Abstract：Based on concrete creep calculation model B3 and mechanical characteristics of concrete-filled steel tube (CFT) beam-column members of large eccentricity, a creep calculation model of CFT beam-column members of large eccentricity is constructed, which accords with mechanisms of concrete creep, and creep characteristics of concrete core of CFT beam-column members of large eccentricity have been taken into account.
Qi studied mechanical behaviors of circular CFT members under long-term load and creep experiments of circular CFT beam-columns were carried out during 1983~1984[7].
However, just a few factors were involved in the equation, so that the method could not be spread widely.
The detailed calculation process is as follows: (1) The member is discretized, geometric properties are constructed, and depth of neutral axis and curvature are assumed
Conclusion From the analysis and calculation results presented in the paper, several conclusions are drawn as follows: (1) From plenty of creep curves shown in the paper, we see that CFT creep develops quickly at the beginning, 80% of which in five and half years is accomplished within the first 500 days, while after that, creep curves still trends upwards but much slower than before; (2) Among all factors that affect CFT creep, internal factors, such as water to cement ratio and aggregate to cement ratio, do not play a leading role; however, it’s the external factors that are dominant in creep parametric analysis, among which steel ratio and axial load seem to have the greatest effect on CFT creep shown from the previous study.