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Since both pre-rolling and finish-rolling area contains slot of cross groove, the groove parameters will affect the effective regeneration of the die-plate geometry and therefore need to be taken great care.
Screw angle and friction factor influence the thread-rolling quality significantly.
However, slippery phenomena did not disappear until the friction factor was adjusted up to 0.6 and higher.
These portions are then assembled into the whole screw and the mass property of the screw can then be calculated, as shown in Fig. 4.
Li, Investigation on 3D finite element analysis and processing parameters for porthole die of Al extrusion, Master Thesis, National Cheng Kung University, Graduate School of Mechanical Engineering, 2003

These factors are directly driven by the rapid development of coal industry, which also reveals a problem -- the security of personnel under mine.
The use of computer network can make a specific assessment of the mine, and mine personnel WEB network detection system can be safe in affected when timely safety tips based on, to ensure that there are appropriate timely security emergency measures in the mining process, we use the coal resources management information system in WEB network on this basis.
The equipment technology of mine coal mining information revolution not only coal industry and efficient production also has a solid security, reduce property loss.
Information technology has the advantages of clear use, the operation is simple and easy to understand, all aspects of use of adaptability, it is also the important factor to promote the rapid development of coal industry.
Test and mechanical wear detection including gas pressure.

Then, the procedures of lifetime prediction in real applications are addressed, which include power loss calculations based on the actual mission profile, the conversion of power loss profile to temperature profile according to the module's thermal properties, the temperature cycles counting by Rainflow algorithm, and lifetime calculation by the fatigue linear accumulation damage theory.
Then, the temperature profile of a module in running is derived based on the module’s thermal properties.
Reliability and Lifetime Assessment Tests In the application, power modules are exposed to both passive temperature swings due to environmental factors and active temperature cycles generated by power consumption in operation.
Therefore, factors such as wire bonds dimension, current, silicon thickness were taken into account in reliability analysis and lifetime modeling.
Feller, Model of power cycling lifetime of IGBT Modules - Various Factors Influencing lifetime, Integrated Power Systems (CIPS), Mar. 2008

., the velocity distribution in the portholes, and how extrusion parameters affect this velocity, significant investigations within this field are not known to us.
Now full sticking friction was set on all tool surfaces except for those near to, or in the die exit, where friction was specified as Tresca friction with a friction factor set equal to 0.6.
The figure depicts that the FEA-prediction is that the flow velocity down the middle of the porthole channels is not significantly affected by extrusion velocity.
And, when the ram head advances close to the front end face of the die, there will be a geometrical constraint affecting the metal flow above the small porthole, making metal flow across the plane A-A, in Fig.8, more and more difficult as the gap between the ram head and the die closes in.
Tomesani, Seam Welds Modeling and Mechanical Properties Prediction in the Extrusion of AA6082 Alloy, Key Eng.

The results showed that the maximum load-deflection and failure type are affected by the Di/D0 and the reinforcement method.
Many research results on the basic mechanical properties and earthquake resistance of CFDT members have been reported in South Korea and abroad [2,3,4].
Therefore, as basic research on CFDT beams with SMAs and rebars installed at the interface between the steel tube and the concrete, this study performed a 3-point bending load test and explored the effects of the properties of SMA and rebars at the locations where they have been installed, the inside-outside diameter ratio (Di/D0), and the concrete strength on the flexural and shear forces.
Phase transition temperature (℃) Physical properties Elasticity modulus (MPa) Tensile strength (MPa) Yield strength (MPa) Mf Ms Rf Rs As Af 2291 1373 528 4.4 26.5 36.3 45.8 52.7 58.6 Note: Ms-martensite start temperature, Mf-martensite finish temperature, Rs-R phase start temperature, Rf-R phase finish temperature, As-austenite start temperature, Af-austenite finish temperature Table 4 Test results of CFDT beam.
Table 3 shows the step-by-step variation temperatures and physical property values for SMA.

Over the past decades, the unique properties of silsesquioxane polymer have been exploited in various electronic applications such as photoresist for lithography [3-4] and optoelectronic devices [5].
The unique properties of HSQ in lithography application are closely related to the silsesquioxane cage structures which could retain the high resolution pattern after curing and developing processes.
Here, Wilkinson’s catalyst was utilized to affect a regioselective hydrosilylation reaction whereby a selective bond formation at only one end of Si-H groups in disiloxane monomer reacted while the other is left intact.
Besides, Karstedt’s was a considerable reactive catalyst as compared to Wilkinson’s [11] and this factor is important in hydrosilylation process involving large molecule compound such as silsesquioxane.
The lithographic properties in term of developing processes were quite good but need further optimisation.

Introduction Carbon steel is commonly used because of its low cost and excellent mechanical properties.
The salinity of water is another important factor for it affects the solubility of the gases [2].
Both the strength of adsorption and the inhibition efficiency depend on the structure of organic compounds, the physical and chemical properties of the metal and the corrosive media [14].
This chemical compound has some property against metal corrosion in heterogeneous acidic media, but the inhibition efficiency is relatively low.
Thus, it is important to make it clear what the property of thiazole is.

Because of the properties of PO43- and AsO43- are very similar, so they often form various types of arsenate-phosphate solid solutions.
There are few experimental data on the thermodynamic properties of calcium arsenate hydroxyapatite [Ca5(AsO4)3OH] in literature.
The incorporation of trace elements into Ca5(PO4)3OH and Ca5(PO4)3OH-like minerals has a considerable influence the mechanical and physiochemical properties of the crystals and significantly affects their reactivity and solubility [30].
The thermodynamic and kinetic properties of svabite dissolution have never been investigated by anyone but Zhu [24].
Fleet, in: Phosphates: Geochemical, Geobiological, and Materials Importance, Compositions of the apatite-group minerals: substitution mechanisms and controlling factors (2002)

Introduction Concrete is the most widespread construction material because it is easily produced and provides excellent mechanical properties in long-term.
A common drawback of this material is the formation of small-sized cracks, occurring due to shrinkage or because of the presence of physical-chemical corrosion factors, that reduce the service life of the structure and increase maintenance costs.
A cementitious material with inbuilt self-healing properties and competitive cost could be considered as a solution for confronting the problem.
Two binders (Table 2) were employed; the first (C1) was used as control, whereas C2 included chemical additives that are supposed to provide the self-healing properties to the final material.
Their properties are reported in Table 4.

We have investigated the role of the Si excess on the photoluminescence properties of Er doped substoichiometric SiOx layers.
In this paper, we will report our study on the luminescence properties of Er doped SiOx layers having different Si contents.
Films having a good morphology, high stability, and very promising optical properties were obtained through a careful optimization of the annealing conditions.
The optical properties of the as-deposited and annealed Er-Si-O films were studied by photoluminescence measurements.
The PL properties of the Er-Si-O/Si multilayer were explored within a wide range of annealing processes.