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Online since: December 2014
Authors: Yan Ying Guo, Zhi Gang Liu
An incremental risk reduction programmer is proposed.
The first step of which is to field example sensors in an airport environment to collect the data with which to validate the conclusions of this report and to develop the data processing algorithms.
The structuring element (SE) g has a normalized weight factor and its elements are calculated such that the center point’s weighted is 1 and the farthest point’s weight is assigned a weight factor, leading to an emphasis on the effect of the central point and a reduction of the effect of the neighborhood points.
The structuring element g has a membership factor and its elements are calculated such that the edge points’ memberships are 1 and the rest points’ memberships are assigned a membership factor, leading to an emphasis on the effect of the edge points and a reduction of the effect of the neighborhood points.
Online since: February 2012
Authors: Zhen Chong Wang, Yan Qin Zhao
Take a two-dimensional structure of slide templates, shapes can be linear, circular, cross and circle the ring, then sort the values pixel by pixel of the template, generate monotonic increase or decrease of two-dimensional data sequence.
Because most of the noise underground coal mine is impulse noise, according to the principle of median filtering which is based on data sorting, the probability of using unpolluted pixel value to replace noise point is very large, so the noise suppression effect is better, while the screen still maintain clarity.
As there are a lot of impulse noise underground so the original image (Fig.1 (a) Fig.2 (a)) first used median filtering method for noise reduction, and the reduction effects are shown in Fig.1 (b) and Fig.2 (b) below.
But because of the contrast of the image is still low, background and foreground resolution is not very clear, so on the basis of the initial noise reduction using the histogram equalization and adaptive histogram equalization to enhance the images.
Online since: July 2007
Authors: Xing Dong Zhang, Xu Dong Li, Yong Lie Chao, J. Ma, K. Zhao, B. Shi
The introduction of additive aids is believed to be an efficient means for the reduction of sintering temperature and the control of grain growth.
The data as a function of pressing force are listed in Figure 3.
However, as described above, a system of TiO2, MgO, SiO2 and CaO was used as additive aids in this study, a combinative effect was plausible for the explanation of the reduction in sintering temperature and acquirement of good densification. 2.6 2.65 2.7 2.75 2.8 2.85 2.9 2.95 5 6 7 8.2 9 pressing force�KN� density�g/cm 3 � 2 2.5 3 3.5 4 4.5 5 6 7 8.2 9 pressing force�KN� vickers hardness�GPa� Figure 3 Density of the green bulk (upper) and Vickers hardness of the products sintered at 1450°C (lower) as a function of the initial die pressing force Figure 4 Comparative SEM photographs of the sintered product without TiO2 (left, 86.76%Al2O3, 9.70%ZrO2, 1.21%SiO2, 1.21%MgO and 1.12%CaO) and the product containing TiO2 (right, 78.18%Al2O3, 17.74%ZrO2, 0.12%SiO2, 0.78%MgO, 2.63%TiO2 and 0.67%CaO) Another two kinds of ZTA nano-ceramic composites were further studied.
Obviously, the good result achieved with the composition of 80.55%Al2O3, 13.95%ZrO2, 0.46%SiO2, 1.05%MgO, 2.79%TiO2 and 1.20%CaO is due to the combinative effect of TiO2, MgO, SiO2 and CaO system, including the prohibition of abnormal grain growth and the reduction of sintering temperature.
The relevant study provides reliable data for the exploration of such ceramics as dental prosthetic materials.
Online since: December 2012
Authors: Xiao Dong Zheng, Lin Fang Shen, Yan Zhong Ye
So, the improvement in the performance of mc-Si solar cell can directly contribute to energy saving and CO2 reduction of the world.
One of the important ways of minimizing this detrimental effect and subsequently improving the conversion efficiency of solar cell is a reduction of the reflectance using an appropriate antireflection coating (ARC).
The data of PAM1.5(l) was adopted from reference spectra of ASTM G173-03.[5] (2) Sampling and measurement results The mc Si solar cell sample is supplied by Hangzhou Sunny Solar Energy Co.
The results of sampled along left vertical red lines in Fig.1 are shown in Fig.2 with data 1-10.
As a comparison, the right side of picture appears porous structure; multi-reflection inside of porous structure will benefit the light absorption of solar cell.[6, 7] 2000X 400X (b) (a) Fig. 5 Surface topographic structure in crystalline grain boundary of region 2 Conclusions The reflectance reduction is a straightforward approach for improving optical to electrical conversion efficiency of photovoltaic solar cell.
Online since: March 2013
Authors: Mei Ling Duan, Xue Yong Zhao
With the increasing of recycled coarse aggregate contents (30%, 50%&100%), the elastic modulus of RC gradually lowered; for different compressive strength levels, with the reduction of W/C, the elastic modulus of RC increased.
In the previous studies, generally agreed that the elastic modulus of RC is lower than NC, the reduction is about in 15% ~ 40% [8], and it is consistent with our test results.
The reduction of elastic modulus will result in increased deformation under the load.
In order to better respond to the relationship between Ec and fcu, in this paper, we combine the data of the experiment with the relevant test data of the domestic and foreign scholars, we carried on the statistical regression analysis and obtained the equation of Ec for RC as follows: (4) equation (4) can better reflect the relationship between Ec and fcu for the RC and fit best to the results of experiment.
Online since: October 2011
Authors: Pei Hao Zhu, Lian Hong Zhang, Bing Yu, Qi Zhi Xie
Tab. 1 Analysis results of rod 1and rod 4 with the mechanics of materials Test number of 1,4 bar The initial preload (MN) Final preload (MN) Reduction the amount of preload (MN) Preload reduction rate (%) 1 19.6 14.5 5.1 26.01 2 23.2 17.1 6.1 26.29 3 42 31 11 26.19 4 44.6 32.9 11.7 26.23 5 46.5 34.3 12.2 26.24 6 55.4 40.9 14.5 26.17 7 64.4 47.5 16.9 26.24 Fig. 3 Analysis steps of preload force with abaqus 3 Analysis of tie rod preload of 100MN hydraulic press with the finite element Obviously, total preload force of four tie rods with 100MN hydraulic press is F=1.3×108N, the preload force of each tie rod with =3.25×107N can be obtained.
In order to ensure that each tie rod of final preload force is the same value, the rod 1 and rod 4 of the initial preload force must Tab.2 Analysis results of rod 1and rod 4 with the finite element Test number of 1,4 bar The initial preload (MN) Final preload (MN) Reduce the amount of preload (MN) Preload reduction rate (%) 1 30 14.5 15.5 51.67 2 34 17.1 16.9 49.71 3 55 31 24 43.64 4 58 32.9 25.1 43.28 5 60 34.3 25.7 42.83 6 70 40.9 29.1 41.57 7 80 47.5 32.5 40.63 be calculated as follows: (1) rod1 and rod4 with the initial preload force of seven groups (30MN, 34MN, 55MN, 58MN, 60MN, 70MN, 80MN) are set.
Fig. 7 illustrates this preloading process of rod 1, and Tab. 2 shows seven groups data with ABAQUS. (2) the rod2 and rod3 with 32.5MN of the initial preload force are applied, which is submitted for analyzing and calculating with ABAQUS[11-12]. (3) the results are outputted.
Fig. 4 Stress Analysis results of frame Fig. 5 Stress analysis results of preload force with rods Fig. 6 Displacement analysis results of preload force Fig. 7 Multi-steps analysis of rod 1 in preload force Fig. 8 The fitting curve of 1,4 rod preload force changes Tab. 3 The Analysis data of 1,4 rod in preload force X / MN final preload 14.70 17.40 31.40 33.40 34.80 41.40 48.00 Y / MN initial preload 30.00 34.00 55.00 58.00 60.00 70.00 80.00 According to the preload force analysis of the definition steps, the analysis results with 100MN hydraulic press of preload force are obtained: (1) preload force of the first group tie rods reduce; (2) final preload force of the second group tie rods equals to initial preload. 4 Conclusions This paper conducts the study on the preload force of 100MN hydraulic press with respectively mechanics of materials and the finite element methods, which calculates the four tie rods of the initial preload force, and compares
Online since: January 2011
Authors: Bi Feng Yin, Yong Hong Fu, Xi Jun Hua, Pei Yun Zhang, Yan Hu Zhang, X.K. Liu
Kimura [8] researched the effects of circular grooves on reduce friction for golf ball, whether the drag reduction was significance or not depended on the location of grooves.
Yamagishi [9] carried out a study on numerical analysis of the circumferential motion over a cylinder with textured grooves on which external face in large Reynolds number case, and found cavitations occurred at the inner of texturing groove, simultaneously, the transition of cavitations was assigned from laminar to turbulent boundary layer, and the reduction of the friction coefficient of texturing surface was performed.
The width w and depth hp of micro-groove have effects on load supporting capacity and reduction of friction; here numerical results are showed in the name of total pressures, wall shear stress and related mean friction coefficient, and net calculating forces.
Fig. 3 The mean friction coefficient for different grooves Fig. 4 The net forces of various structure of grooves The data of mean coefficient of friction for various micro arc-grooves were obtained by the mathematic method of surface integral for wall shear stress τ and total pressure loaded on sliding surface, which was shown in Fig. 3.
The proposed technique is easy and allowable to obtain an optimized data of micro-groove for hydrodynamics lubrication.
Online since: November 2006
Authors: Pier Gabriele Molari, Gianluca Cricca, Piero Morelli
Deformation measures as well as the applied load and the absolute position of the machine piston were acquired by means of a NI SCXI 1600 data acquisition board and processed by a LabView virtual instrument.
Load versus displacement charts were used to register abruptly reductions of the axial stiffness, that are clearly recognizable symptoms of buckling in progress.
Nevertheless, a reduction of the axial stiffness takes place, and is well recognizable on the chart because the piston stroke increases with a reduction of the load support capability of the system.
Fig.6 - case fracture Fig.5 - arm collapse Fig.7 - model geometry The unknown value of the bending stiffness K has been optimized by numerical least square fit of the experimental data.
Online since: October 2013
Authors: Shun Bo Zhao, Yang Yang Xu, Yu Tao Li
Based on the test data, the formulas for forecasting the carbonized depth of MSC are suggested.
Meanwhile, as the larger water to cement ratio was got by decreasing the cement dosage with constant water dosage, which brought about the reduction of cement hydrates that could be carbonized.
The follow forecast model of carbonized depth of MSC will based on the analyses of test data in these ranges.
Fig. 3 and Fig. 4 show the fitness of above formulas with test data.
Fig. 3 Fitness of formula (1) with test data Fig. 4 Fitness of formula (2) with test data Conclusions To improved the engineering application of concrete with machine-made sand, the resistance of this new concrete to carbonization was studied with the comparison of ordinary concrete.
Online since: October 2015
Authors: Howard Smith, Parvathy Rajendran
The battery energy density and solar efficiency’s extrapolated forecast data do not show any sign of technology maturation.
Methodology Data on solar-powered electric UAV model specifications were obtained from a previous work [18] because of the availability of such data and the successful flight tests already conducted.
Solar efficiency’s extrapolated forecast data show a linear increase with time at roughly 0.47% per year.
In addition, the reduction in control weight decreased to 23.0% and it is nearly 0.09 kg in 2036.
Both battery energy density and solar efficiency’s extrapolated forecast data do not show any sign of a maturing technology.
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