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Introduction Practically on every object in our surroundings is affected by number of negative factors, which are for example impacts of snow, wind or freeze.
In the past was wetness in masonry manually decreased by mechanical methods.
For testing of properties of injection gels were chosen following laboratory exams.
Addition of injection gels improved all of tested properties in all tested materials.
[4] ČSN 73 1357: Determination of capillary properties of aerated concrete

The drawbead amount, position, size and form were studied for their affects on the formability. 3 drawbead patterns with 3 different heights were examined.
Demeri [3] identified the material properties, the penetration of drawbeads and the lubrication with FEM.
At this step, the material properties, the load boundary conditions and the tool motions were defined.
They can be avoided by increasing the punch and die radius to support the flow of material into the die or by choosing the appropriate lubricants with properties to reduce the friction between the contact surfaces of the blanksheet and die.
During the design process the restraining force and the drawbead exit thickness are 2 main factors in the sheet metal forming process [9], which are results from the selection and positioning of the drawbead lines.

There exist many dangerous and harmful factors in by-product steel gas power generation process and which easily caused casualties and the pollution of the environment.
(2)The determination compensation factors of safety measure.
The safety measure compensation factors were analyzed according to the specific circumstances of process unit.
Table 1 Fire, explosion, toxicity index on combustion unit Project Combustion Main material CO 1．material factors（B） 6.0 2. special material hazard range of hazard factors hazard factors A mix and dispersion characteristics -60～60 -20 B sensitivity of catch fire -75～150 150 C explosion properties of gas 150 150 special material hazard calculation（M） 280 3. general process hazard A use and only Physical change 10～50 10 B container of may transport 10-100 25 general process hazard calculation（P） 35 4. special process hazard A high pressure 0～150 75 B high temperature 0-40 25 C joint and gasket leakage 0-60 20 D explosion hazard above average 40-100 100 E static electricity hazard 0-200 35 special process hazard calculation（S） 255 5. quantity hazard factor of quantity Q 1～1000 100 6．hazard of configure A structure design 0～200 20 B the domino effect 0-250 10 C others 0-250 25 hazard of configure calculation（L） 55 7．toxicity hazard A TLV value 0-300 130 B material type
Therefore, various factors and logical relationship of boiler explosion were analyzed by fault tree analysis [7].

Introduction Wrought aluminium alloys have a number of desirable properties such as low density, high specific strength and excellent formability that make them particularly attractive in various applications such as aviation and automotive [1].
In this article, the effect of combined electromagnetic and ultrasonic fields on the grain refinement of molten AA7449 has been investigated and the resulting mechanical properties evaluated and compared with AA5754 [13].
The mechanical properties resulting from each technique were evaluated and compared.
The mechanical properties (i.e.
Mondolfo, Aluminium alloys: structure and properties, Boston: Butter- worth, 1976

., Huwei, Yunlin 632, Taiwan, sylin@nfu.edu.tw Keywords: process parameters, negative strain hardening rate, mechanical force, hydro-forming, magnesium alloy.
Although low ductility and poor formability properties are always accompany Mg alloy at room temperature due to the hexagonal closed-packed crystal structure, the development of some effective forming techniques overcoming this forming difficulty for this kind of material is strongly worth exploring in industry.
The investigated factors are type of lubricant, initial extrusion speed, temperatures and type of material.
ANOVA was used to investigate how parameters affect the extrusion process.
While punch velocity and shear friction factor were set at two and three levels, respectively.

Therefore, an adequate thermo-mechanical hot stamping operation is necessary.
For example, due to the semi-finished material’s physical properties, as e.g. high heat capacity regarding heat treatment, the process design parameters and the tool design had to be adapted.
Within the scope of thermal treatment this particularly affects the holding times of components when being heated and quenched during the hardening process [1].
One option to enhance the strength and, thus, wear resistance of steels is the thermo-mechanical method shown in figure 2, which refers to ausforming processes.
The essential factor is an immediate quenching process following the forming operation, e.g. by a heat transfer into a pre-cooled tool.

In this paper, GPS from different areas of Sichuan province was investigated; activity and impacts of fineness and content on properties of cement mortar were studied in order to provide some technical reference for GPS as pre-mixed concrete admixtures.
Although GPS having a potential activity, its activity is controlled by the chemical composition, fineness, vitrification degree and other factors [9].
Concrete: Microstructure, Properties, and Materials[M].
Influence of phosphate slag on hydration properties and pore structure of cement paste [J].
The influence of admixtures on the properties of phosphorous slag cement[J].

Influenced by various factors, the content of Powder clay is the most variable and most changeable component in Aeolian sand, especially in the desert edge and peripheral zone where human activities and road network distribution are relatively large: mostly mobile sand dunes, semi-mobile sand dunes and fixed sand dunes alternate with each other. the content of Powder clay in Aeolian sand varies greatly [6-7].
It should be noted that it is relatively difficult to obtain the ＜0.075mm part (sample z) from silty extremely fine sand by sieving, and due to the influence of various factors in the later stage, it cannot be obtained in large quantities. therefore, the "soil reuse" method described in the specification is adopted, i.e. the sample with a certain Powder clay content is tested under the condition of extremely low water content first, then the sample is reused, and water is added to the water content of 1%, 2%, 4%, 7%, 10%, 13%, 16% ...respectively until saturation or super saturation is reached during further tests.
However, when the content of Powder clay is a fixed value, the compaction density is mainly affected by the pseudo cohesion caused by capillary water and the cohesion produced by Powder clay.
Cheng, Granular mechanical analysis of the strength and dilatancy of sands, Eng.
Hu, Study on Aeolian Sand properties of desert subgrade and compaction mechanism, Highway, 6 (2013) 20-24

The objective was to identify the significant process parameters that affect the output characteristics.
Introduction Metal Matrix Composites (MMCs) are extensively used in structural, aerospace and automotive industries because of its light weight, high specific strength, good wear resistance properties.
The factorial portion of CCD is a full factorial design with all combination of the factors at two levels (high, +1, and low, -1) and composed of eight star points, and six central points (coded level 0), which is the midpoint between the high and low levels, corresponds to an α value of 1.
The factor settings with maximum total desirability are considered to be the optimal parameter conditions.
The main significant factors that affect the MRR are pulse current, pulse on time and pulse off time whereas voltage remains insignificant.

Introduction Duplex stainless steels (DSSs) consisting of a dual structure of austenite (g) + ferrite (a) possess the superior mechanical and corrosion properties, and have been applied to various industrial fields such as petrochemical, power and seawater desalination plants.
On the other hand, during fusion welding, DSSs undergo the complex microstructural change and phase transformation affecting the a/g phase balance due to the weld thermal cycle [3,4].
Comparing the hardening behaviour in each region of weld (WM, HAZ and BM), the major factor affecting the progression of 475˚C embrittlement was clarified and the mechanism of 475˚C embrittlement in DSS weld was discussed coupled with the thermodynamical consideration.
(a) Base metal (b) Weld metal (c) Heat affected zone Fig.8.
Mcpherson, Y.Li and T.N.Baker: “Microstructure and Properties of As Welded Duplex Stainless Steel”, Sci. & Technol.