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To obtain statistically reliable data,for each experimental condition, matrix of 8x8 (64) indents were carried out.
The contact depth, hc, can be estimated from the load-displacement data as (Eq. 2): hc=hmax-e(Pmax/S) (2) where hmax is the maximum indenter penetration depth at the peak load, Pmax, e is a tip dependent constant, Sis the material stiffness.
At the same time, the substrate recorded a significant hardness reduction starting from 973 K, and at 1173 K their hardness was as low as 3-4 GPa, which, compared to the room temperature value of 13 GPa, means a dramatic reduction of 70-78%.
Present results are in good agreement with some previously reported data on similar coatings [6,8,9,28-32].
Nix, A method for interpreting the data from depth-sensing indentation instrurnents, J.

What’s more, the fatigue life of fire damaged box girders strengthened using SPCCS technique was evaluated based on monitoring strain data, and the further bridge maintenance suggestions were proposed based on the assessment results.
Second, material property of burned concrete should be considered by multiplying reduction factor to consider the effect of fire to stiffness of the whole bridge.
Considering fire effect for bridge integral rigidity, elastic modulus reduction was considered for severe injured concrete.
Conclusions To effectively simulating mechanical behavior of fire injured Yao Zhou Downlink Viaduct by ANSYS, it was to use respectively different reduction-factor of elastic modulus for concrete according to different burned degree.
What’s more, the fatigue life of fire damaged box girders strengthened using SPCCS technique was evaluated based on monitoring strain data, and the further bridge maintenance suggestions were proposed based on the assessment results.

With the help of experimental and theoretical data and the methodology of approach to the subject, several aspects have been clarified regarding the depth of the asperities on the honed surface compared to a process-smoothed surface.
The reduction of the layer altered by the previous machining, as well as the existence of micro-depths serving as lubricant deposits contribute to increasing wear resistance of the cylinder surface.
With the reduction of the tga value, there is an improvement in the quality of the surface, but productivity decreases.
The reduction of the layer deformed by the previous machining, as well as the existence of micro-depths serving as lubricant deposits contribute to increasing wear resistance of the cylinder surface.
With the help of experimental and theoretical data and the methodology of approach to the subject, several aspects regarding the depth of the asperities on the honed surface compared to a process-smoothed surface have been clarified.

The academic novelty of the work consists in identifying the regulations in the influence of PFM, obtained on the basis of resorcinol-formaldehyde oligomers, on the strength reduction of concretes in biologically aggressive media, which consists in the peptizing action of PFM and finely-crystalline structure formation, which contributes to cement stone compaction and reduction of micro-cracks inside concrete and on its surface.
The analysis of the obtained data (Tab.1) has demonstrated that the fungi-resistance of concretes under study is greatly influenced by the age and porosity of samples, as well as by alkalinity of medium.
Analyzing the strength properties alteration dynamics of samples (Fig. 1,2), we can see that in the initial period (1–7 months) the inoculated samples are characterized with a certain strength enhancement, but then (8–12 month) the strength reduction is observed, especially for samples LC-4 and HC-4.
The peptizing action of SP SB-3 results in the formation of more finely-crystalline structure, which contributes to cement stone compaction and reduction of micro-cracks inside concrete and on its surface.
The strength characteristics of the cement stone with the researched modifiers are not reduced at mold fungi spores’ contamination, but, on the contrary, slightly increase due to the increase of cement paste fluidity, decrease of W/C ratio, reduction of micro-cracks in concrete and compaction of its structure.

The data of ammonia are relevantly 22.17%, 11.45% and 56.38%, indicating that the soluble fraction, which is also poor in biodegradability, plays a key role in SE treatment.
Fig. 4 COD variation of filtration permeates (a) and percent distribution of COD fractions (b) The BOD data and the BOD/COD ratios are given in Table 1.
According to Fig. 6, the 4-scale filtrations provided a total ammonia reduction of 95.65%, or from 12.42 mg/L to 0.60 mg/L.
After the whole filtration procedure, AN decreased from 5.3mg/L to 3.2 mg/L, with a reduction of only 39.62%.

Ground reaction force at anterior posterior direction was calculated from force platform (9286A, KISTLER, JAPAN) data.
Data Analysis.
Data at the first cycle of each perturbation need to be eliminated for next calculation to avoid movement bias due to introduction of perturbation.
Experiment data were compared with simulation data obtained based on eq. (2) which was developed by using Simulink.
Elimination of first cycle data (dash line) to avoid movement bias and passive movement.

The presented data have been selected from the authors’ most recent research, which supports an economic development of a lightweight composite with the ability to withstand elevated temperatures of up to 1000 °C.
Apparently, the combination of fibres and the air-entraining additive causes an increase in the air content in the composites, which leads to a considerable reduction in bulk density.
The chemical decomposition of hydration products and the content of siliceous components in the mixture have a major impact on the reduction of the bulk density values.
The reduction of flexural strength is lower than that of compressive strength.
The evaluation of the bulk density results is also of importance, where the reduction of values due to air-entraining additive is evident.

The inserts profile and geometry data are presented in Fig. 1.
Significant amount of reduction of chatter amplitude may be observed from this figure.
Reduction at other conditions is not that significant.
Reduction of the amplitude of machining vibration at other trial runs is shown in Fig. 4.
Heating at 420 0C helps in lowering down acceleration amplitude and the maximum reductions were 600%. 3.

Thus, the reduction of the primary particle size and application of amorphous precursors could enhance the densification of Si3N4-based compacts.
A new possibility for preparation of Si3N4 based powders comes from the top-to-bottom method, if particle size reduction could be achieved by the fracturing and wear of tough silicon nitride particles.
The reduction of AlN crystallite size was noticeable after milling for 30 min. with silicon nitride balls.
Thus, it could be concluded that in the first step the reduction of the size of AlN crystallites took place and was followed by the oxidation of the fine particles during prolonged milling.
Measured and calculated from the XRD data weight fraction of oxygen in the activated powders The measured oxygen content was always higher than that calculated from the XRD results, thus oxidation of silicon nitride during milling is confirmed.

With M=46 (Hamming) the two window have equal main lobe width but the proposed window offers -5.3 dB side lobe reduction.
The reduction in side lobe peak is 18.5 dB with M=10 (-55.2 dB compared to -36.7 dB).
It is obvious that the proposed window also outperforms the Hanning and Bartlett windows because Hamming window shows better side lobe reduction than these windows for the same main lobe width.
Finally, for the same specification proposed modified Lanczos window shows more side lobe reduction with slight increased main lobe width in comparison with *new window [9].
Zierhofer,“Data window with tunable side lobe ripple decay”, IEEE Signal Processing Letters, vol. 14, no. 11, Nov. 2007