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If the rated temperature is exceeded over any period of time, the service life can be significantly reduced due to breakdown in insulation dielectrics and thermal fatiguing of components. [1] When the transformer winding insulation property reduces, there will have a significant impact on itsheat-conducting property.
When the temperature goes up to a limitation, it will reduce insulation property and decrease service life or even cause insulation breakdown, transformer burned to explosion.
In the long term, affected by the environmental conditions and physical or chemical effects, insulation materials’mechanical strength and electrical strength of transformers decline gradually which causes insulation aging.
Insulation aging of transformers mainly due to the chemical reaction caused by temperature, oxygen, humidity and other effects in which high temperature is a direct factor.
High hot spot temperature declines the mechanical strength and electrical strength, makes insulation strength degradation, and causes transformer fault easily.

Since the penetration depths can amount to several hundred micrometers, the tracer atoms sample a huge amount of individual GBs supplying statistically reliable information on the GB diffusion properties.
The segregation factor s is important for the flux (ii) and both factors, s and sa, affect the flux (iii).
Due to the applied mechanical sectioning method the nanocrystalline GB diffusivity Dgb could not be analyzed in that experiment.
The segregation factors s and sa should be known to evaluate � and �a.
For the analysis of Fe and Ni diffusion the relevant segregation factors sFe and sNi are close to unity.

The accuracy of localization with NAVSTAR GPS depends on several well-known factors: • satellite geometry, • atmospheric effects, • multipath effect, • relativistic effects, • other errors.
The choice of the coordinate system affects the accuracy of localization and convenient determination of the particular coordinates.
DOP and satelite geometry The accuracy of localization using GPS is affected by various sources of errors.
As the precision and physical properties of the receiver are given, the crucial problem is to choose appropriate method applicable with relatively low computing resources.
Kenderová, Friction Effect Analysis of a DC motor, American Journal of Mechanical Engineering (2013), Vol. 1, No. 1, pp. 1-5

Requirements laid on extrication equipment are the same in all European countries and producers have to fulfill all actual requirements concerning performance, characteristics, properties, safety and maintenance according to this standard. [1] These requirements of course change in accordance with vehicle development.
It is necessary to mention also several railway accidents and crashes of vehicles and trains. [3] All of these mentioned factors lead to the fact that many injured persons were captured in crashed transport means and it was necessary to extricate them as soon as possible. [4] Due to increased number and seriousness of traffic accidents, it was necessary to increase technical equipage, and speed and flexibility of responding members of firefighting and rescue units.
They are divided according to performance (Table 4) and power unit – with engine or mechanical power energy.
The equipment used in an actual situation is affected also by other factors.
References [1] MARKOVÁ, I. et al.: Protection of persons and property against fire.

As a result, the inhomogeneity of thermal properties of the tested component, or the presence of some imperfections, is revealed as temperature variations of the component's surface.
Material and methods The proposed nondestructive evaluation method of anticorrosive Aluminium coatings by pulse active IRT consist of the following stages: - The Visual Test (VT) of sample surface in order to assess the surface imperfection such as spatter or pore and oxide, which could affect the quality of IRT examination.
After filling the holes with lead, the final machining of the calibration block was made and then it is subject to the blasting operation to ensure an appropriate roughness to provide a good support for mechanical anchoring of coating layer on the base material.
As influence factors (IF), the following three technological parameters were chosen: the spraying current intensity, spraying speed (the travel speed of the spray head in relation to the component) and spraying distance (distance between the spray head and the component).
It is well known that the main mechanism to accomplish the adhesion between the coating layer and substrate is "mechanical anchoring" of sprayed molten material particles, achieve during their cooling when they reach the micro-irregularity of the substrate.

Thermal characteristics affecting materials’ performance as insulators.
Thermal transmittance and thermal conductivity are the properties that most affect materials’ performance.
Acoustic and other characteristics affecting materials’ performance.
Depending on core materials, thermal properties will vary.
Effect of expanded perlite on the mechanical properties and thermal conductivity of lightweight concrete. 

A detailed study of cladding thickness and strength, residual stresses and through-thickness material property changes has revealed that this asymmetry results from a complex combination of these parameters.
These variations made it impossible to definitively state the affect of cladding thickness on the final springback.
The other influencing factor highlighted by Yoshida et al. [1, 2] was cladding strength.
The presented data indicates that springback differences are due to a combination of factors.
On Springback of Double Curved Autobody Panels, International Journal of Mechanical Sciences, Vol. 43 (2001), pp. 5 - 37 [9] http://www.math.sunysb.edu/~scott/mat331.fall96/project2/ [10] J.

Ghanic Mechanical and Material Engineering Department, Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia a sati1771@gmail.com, bchase@vlsi.eng.ukm.my, cjaharah@vlsi.eng.ukm.my Keywords: Tool life; wear progression; wear mechanism; surface quality; CVD tool; Ti-6Al-4V; dry machining Abstract.
The chemical composition and physical properties of workpiece material are given in Table 1 and 2, respectively.
At least 3 mm of material at the top surface of workpiece was removed in order to eliminate any surface defects and residual stress that can adversely affect the machining result [10].
Table 1 Factors and levels used in the experiment Factors Levels 0 1 2 A- Cutting speed (m/min) 55 75 95 B- Feed rate (mm/rev) 0.15 0.25 0.35 C- Depth of cut (mm) 0.10 0.15 0.20 The machining trials under dry machining condition and high cutting speed were carried out using the Colchester T4 6000 CNC lathe machine.

Planning Phase The possibility of establishing a highway construction project depends on the existing traffic and transport situation, construction conditions, the impact on the natural environment and social environment, sources of funding, and other factors.
Along with time and the change of environment, the influencing factors of highway will change accordingly.
Roadbed design is mainly affected by cross roads, railways, rivers, pedestrian pathways, etc.
Steel slag and fly ash application technology: because steel slag contains various oxides and minerals which have similar physical and chemical composition of Portland cement clinker, steel slag aggregate has better mechanical properties than rolling gravel, not only wearable, but also with a certain degree of hydration activity, it is suitable as asphalt mixture aggregate and primary aggregate[1].

Because these components are designed to be used over a long-term period at high temperature, one of the most critical properties in their design is time-dependent creep behavior [3].
A material constitutive model needs to be proposed to consider all these factors.
For a design application and a failure criterion for the components servicing at high temperature, the limitation of a strain may be an important factor for ensuring the structural integrity or functional capability of a component [5].
The determination of limit load at high temperature is different with that at room temperature, and the servicing life factor must be considered.
Peng: Creep stress analyses affected by defect geomentries on P91 pipe with local wall thinning under high temperature, The 18th international conference on nuclear engineering, Xi’an, China (2010)