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The criterion followed is typical of vulnerability studies and comprises a visual exam of the structure according to a codified inspection procedure, during which different types of data related to the roof system are collected, and subsequently the evaluation of a series of characteristics of the structural system that determine or influence its capability of developing a suitable seismic response.
The procedure for seismic vulnerability assessment defined for the case of timber roof structures [1, 2, 3], may be summarized in the two following points, Part 1) The structure is inspected according to a standardized sequence and following given guidelines; at this time, data regarding the configuration of the structure, the geometry of its members, its joints, and its construction details, the materials, and the state of conservation are collected.
Classification of conceptual design A) Effect of interconnection B) Effect of dimensions and type Structural scheme Section [cm ´ cm] Span [m] Trusses in orthogonal directions A 6 9 12 18 24 Parallel trusses with transversal bracing A – B 15 ´ 15 A B C Parallel trusses with at least 2 purlins per pent A – B 20 ´ 20 A B C C Parallel trusses with 1 purlin per pent B – C 25 ´ 25 A B B Couple roof (no truss) C – D 30 ´ 30 A A Criteria for evaluating different types of carpentry joints must focus on the capability to maintain connection during load inversion and consequent reduction or loss of contact pressure, and on the identification and exclusion of possible brittle failure modes.
Elimination of initial conceptual errors, like the presence of unrestrained thrusts, not uncommon in old structures built sometimes without a sound conceptual design, is a necessary operation also in terms of vulnerability reduction.
Strengthening operations to improve the response to lateral loads are less frequently found and are, in general, positive on vulnerability reduction, in structures often lacking sufficient specific capability.

Therefore, low water deficit RDI at seedling while full irrigation during flowering to late fruiting could be used to effectively reduce irrigation water application and improve IWUE of processing tomato without causing economic benefit reduction in arid areas.
Introduction Water application was greatly reduced and crop irrigation water use efficiency (IWUE) was significantly improved under regulated deficit irrigation (RDI) in an arid environment [1,2,3], mainly due to the significant water-saving and minor crop yield reduction effect of reasonable RDI [4,5].
The following data in Table 2 were means of three replications and statistically analyzed using SPSS18.0 software.
Therefore, low water deficit RDI at seedling while full irrigation during flowering to late fruiting could be used to effectively reduce irrigation water application and improve IWUE of processing tomato without causing economic benefit reduction in arid areas.

For the extracted fibre, the plasma treatments cause reduction in both interfacial adhesion and the tensile strength, which is sensitive to plasma treatment conditions as revealed by a bimodal Weibull statistical distribution analysis.
For the extracted fibre systems, unexpectedly, the plasma treatments with either O2 or NH3 gas result in remarkable reduction of interfacial adhesion strength.
It is worth mentioning that the various acidic treatments in general results in much remarkable reduction in strength of PBO (not shown here).
The experimental data in Fig. 3 shows qualitative agreement between Gic, γf and D values depending on the fibre/resin systems.

(3) Eq.3 shows that the ratio of adjacent peaks is equal in the free vibration stage, and the damping coefficient can be obtained if the data of two crests or troughs is known, which is shown in Fig. 3.
In order to make the test data more precise, the data of four adjacent crests is used.
The amplitude reduction rate and average reduction are calculated first.
Fig.3 The data processing of viscous damping test Fig.4 One-dimensional of rubber mounting mechanical model of rubber mounting Dynamic Performance Test of Rubber Mounting.
According to the structure, experiment data and previous researches, a nonlinear mechanical model of rubber mounting is built in this paper, which is shown in Fig.6.

An anthracite coal sample is subjected to a range of effective stress conditions in order to investigate a general trend of coal permeability reduction with an increase in effective stress.
(3) α and β are constants obtained from fit to experimental data [3,6,9-12].
Results A general trend of permeability reduction with an increase in effective stress can be observed for the tested sample.
Figure 5 - Klinkenberg plot of measured permeability versus inverse of the mean gas pressure As presented in Fig. 5, measured permeability values follow an approximately linear trend and hence, an extrapolation of measured permeability data up to infinite mean gas pressure is performed.
Despite the lack of data for mean gas pressures higher than 1.6 MPa, it can be inferred from the existing trends that the mean gas pressure required to minimize and possibly offset the slip flow at higher effective stresses would be approximately 2.0 MPa.

The results show that the mode shapes get from ANSYS analysis are consistent with the datas of experimental measurements, and the maximum deviation of natural frequency between experiment and theory is blew 15%.
Gearbox Modal Analysis by ANSYS The commonly used modal extraction methods of ANSYS are: The Block Lanczos law, Subspace method, Power Dynamics method, The reduction method, Asymmetric method and QR damping law.
The Block Lanczos law is very effective in Extracting large, medium-sized modal; Subspace method is more suitable for the extraction modes less than 40 order model, and requires a relatively small computer memory; As a result of the PCG iterative solver, the speed of Power Dynamics method is significantly better than the Block Lanczos method and the subspace methods; The reduction method is suitable for the model does not contain local vibration caused by a concentrated mass; Asymmetric method and QR damping law are applicable to non-symmetric stiffness and mass matrix (for example, the acoustic fluid - structure coupling problem) [5].
In the pilot test, frequency response of the system is generally obtained through the power spectral density function such as Eq.4. . (4) In order to evaluate the datas quality is good or bad, that the result of Eq.5 is reliable when the coherence function value is greater than 0.95. . (5) Here, SFX is input and output cross-power spectrum; SXX is self power spectrum of the system input; SFF is self power spectrum of the system vibration response.
The mode shape results get from ANSYS analysis are consistent with the datas of experimental measurements, and the maximum deviation of natural frequency between experiment and theory is blew 15%.

SEA was seen to be strongly influenced by loading rate and significant reductions in SEA were seen as rate increased.
Load data was recorded via a piezoelectric load cell at a rate of 40kHz.
At impact rate a smaller reduction was seen.
For the single 32mm insert (T12) this caused a small, localised reduction in steady state load, leading to an SEA reduction of 2%.
This rippling caused a slight reduction in steady state load (less than 8%).

Load reduction was used to determine threshold characteristics, and in each case, after determining the threshold data, the mid-upper portion of the stress intensity factor range (ΔK) versus crack growth rate relation was then determined.
A baseline ΔKeff relation was determined in part using compliance based measured crack opening data.
These data provided the basis for development of the combined plasticity and roughness modelling approach detailed in this paper.
The results are compared in Figure 4 with the measured data from [15].
As shown in Figure 4, that raised the crack opening such that it was closer to the measured data.

Time domain analysis of power data indicates that root mean square increases and kurtosis approaches to 0 with crater wear increase in turning process.
The monitoring system includes a power sensor, a data acquisition card and acquisition software.
Power data at that time just before each turning test ending is extracted to implement time domain analysis, see Fig.3.
Fig.4 Xrms of power data with cutting time Fig.5 Variance of power data with cutting time Kurtosis and Skewness results of power data in cutting process are illustrated in Fig.6-7.
Fig.6 Kurtosis of power data with cutting time Fig.7 Skewness of power data with cutting time Conclusions Power monitoring is an economical monitoring solution for machining operations.

Examination of SEM showed that the microstructure of the composites consisted of the equiaxed ZrB2, ZrC and SiC grains, and there was a slight tendency of reduction for grain size in ZrC with increasing ZrB2 content.
It can be seen that there is a slight tendency of reduction for grain size in ZrC with increasing ZrB2 contents.
The fracture toughness data are compared to the best results of the ZrC-ZrB2-SiC composites with the similar composition reported previously and prepared by SPS methods[11] and the ZrC-ZrO2 system [13], although the fracture toughness values show little variation with increasing ZrB2 contents and are statistically identical to each other, considering the standard deviation of the data.
Based on previous studies [7,19], the more tortuous crack path is a qualitative indication that more energy was absorbed during crack propagation and a reduction of crack driving force, which led to the higher measured toughness value.