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The influence of thickness-length ratio and scale effect are considered by introducing the reduction factor of equivalent constraints and concrete strength reduction factor, respectively.
By introducing concrete strength reduction factor [3] and the reduction factor of equivalent constraints [4], which have respectively considered scale effect and the influence of thickness-length ratio, the confinement of square steel tube towards concrete can be equivalent to the confinement of circular steel tube towards it [3-7].
And the numerical results are compared with analytical results and experimental data and good agreement can be observed.
Accordingly, both of the finite element results and theoretical calculation are in good agreement with the experimental data.
(a) Specimen S4L,S4H (b) Specimen I-1,I-2 (c) Specimen H-1~H-9 Figure 2 Stress Contour of STCCFWSRC (Longitudinal) Figure 3 Load Displacement Curve Conclusions From the above analysis it can be concluded that: (1) Both the analytical results and the numerical results agree well with experimental data

Efficiency of water curtains Zdeněk Kadlec, a *, Miloš Kvarčák22,b 1VŠB - Technical university of Ostrava, Faculty of Mechanical Engineering,17. listopadu 15/2172, Ostrava – Poruba, Czech Republic 2 VŠB - Technical university of Ostrava, Faculty of Safety Engineering, Ostrava, Lumírova 13/630, Ostrava - Výškovice, Czech Republic azdenek.kadlec@vsb.cz, bmilos.kvarcak@vsb.cz Keywords: water curtain, nozzle, fire, thermal camera, thermal flux reduction.
Experiments were prepared and realised with a goal to determine the radiant heat flux intensity reduction of fire passing through a water curtain in VŠB, TU – Ostrava.
Emissivity of the flame was determined by comparing these data.
Selected thermal image and its adequate histogram are shown in Figure 2 and the subsequent evaluation of the data obtained is summarized in Table 1.
According to literature [1,2,7], Heat flux calculations were made simply for a closed system by using Equation (7): (7) where: e1,2 … emissivity system, - s … Stefan-Boltzman constant, W.m-2.K-4 T1 … flame temperature, K T0 … ambient temperature, K Having regard to those factors, the resulting radiant heat flux intensity reduction of fire passing through a water curtain have been regulated toward the safety side.

Its main purpose is to find the inherent law of generated data sets.
Be used for high dimensional nonlinear fault samples for learning, in order to identify embedded in high dimensional data space in the low dimensional manifold, can be effective data found the essential characteristics of fault identification.
(1) Among which , yi∈Rd, d is the number of dimensions.The data set {yi} is produced randomly, and is mapped as {xi=f(yi)} of data space through f.
All the data are obtained from a 1km pipeline used for experiment.
The analysis on the frequency spectrum of the pipeline pressure wave data shows that the cut-off frequency of the spectrum is 4 kHz.

Annealing treatments Hot rolled, laboratory-cast samples of TWIP steel samples (5.4 mm thick) of 22% Mn - 0.6% C (in mass-%) were cold rolled to different reductions (40 % to 70 %) in a laboratory mill.
a) Recrystallization fraction for all reductions as a function of time at 600, 650, and 700 ºC.
b) Id. for the 60% reduction at 700 ºC Table 1 shows the individual values of ksoft and B.
Values of ksoft and B obtained from Avrami fittings to the recrystyallization results obtained for different reductions and annealing temperatures.
Combining the data from annealings at 900 ºC, 1000 ºC, 1100 ºC, and assuming as activation energy the value QGG = 363 ± 60 kJ/mol calculated from the isochronal plots, a good fitting of all the grain growth data is obtained with an exponent nGG ≈ 3.9, Fig. 2.

In order to obtain more accurate and rapid voltage fluctuations and flicker signal and provide fast and accurate data for power quality analysis and improvement, this paper proposes the improvement measures of null space pursuit algorithm based on the analysis of the principle of null space pursuit algorithm, which improves the value of practical application.
By the simulation analysis, it proves that the combined null space pursuit algorithm not only has the same advantage of high precision extraction and decent noise reduction capabilities as original algorithm but also improves its computing speed and enhances its practical value.
l Records operation time of the algorithm by MATLAB we can get: null space pursuit algorithm use 10.974839 seconds, the combined null space pursuit algorithm takes 3.411994 seconds, increase operation speed 68.9%.( In order to guarantee the validity of the data, in this paper, the time data are not added the operation time of white Gaussian noise.)
By the simulation analysis, this paper proves that improved null space pursuit algorithm can not only extract more accurate voltage fluctuations and flicker signals but also have good noise reduction function.

Based on EBSD data, a post-processing analysis has been performed in order to study the texture of the flowformed parts.
(a) 60% reduction in thickness (b) 64% reduction in thickness Fig. 3: Photographs of the flowformed tubes investigated in this paper.
This angle appears to decrease when the reduction ratio increases.
This fact tends to demonstrate that the higher the reduction ratio, the more flowforming looks like extrusion (elongation along the roller feed direction i.e. axial); on the contrary, the lower the reduction ratio, the more flowforming looks like rolling (elongation along rolling direction i.e. tangential).
The texture of the α phase can be investigated thanks to EBSD data.

The spectral acquisition circuit, data conversion and storage circuit were designed.
The synchronization of the spectral data acquisition, data conversion and storage were achieved using VHDL.
The system overall The spectral data acquisition system is mainly composed of three parts following as: optical system, the spectral acquisition module and data analysis module.
The data conversion and storage.
The data conversion and storage circuit is shown in Fig. 3.

PCA plays a vital role in statistical analysis as a dimensional reduction tool.
To do this, current work concentrates on using PCA as dimensional reduction and damage detection tool based on a data set that is processed by means of WT.
Then, the result of applying PCA on both original data and data from wavelet ridge is demonstrated and discussed.
Totally, 40.000 data samples are collected.
data from current status of the structure.

In addition, the experiment found that the wind velocity reduction rate is affected by the installation distance of the wind fence.
The reduction in wind velocity brings micrometeorological changes (wind velocity and wind direction) to the protected area.
The number of measurement data was 1024 each time, and measurements were made three times and the mean value used.
The wind velocity reduction effect was highest (50%) at a porosity of 40%.
Overall, the wind velocity reduction rate was higher where the wind fence was installed than where it was not.

Processing To standardize the original data, we may get standardization of indicators according to the value of fuzzy membership function.
To further eliminate the correlation between the data, according to the principles of multivariate statistical analysis, the data may be transformed as （3） where is an n-dimensional random vector, whose matrix may be expressed . cov() is the covariance matrix of .
Table 2 Fractal dimensions of different urban disaster-carrying capabilities Note: "-" indicates no value; primary data sources may refer to literature [11].
Conclusions (1)The data distribution of statistical indicators data distribution of urban comprehensive disaster-carrying capability has obvious fractal characteristics.
But this model is only preliminary, there is imperfection of data sources, data selection, evaluation indicators established, it may not reflect the overall level of the various regions fully.