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Online since: January 2014
Authors: Xiao Bing Pei, Fang Liu
Methodology 3.1 Data collection This raw data was derived from the “Statistical Yearbook of Pudong New Area”, “Shanghai Statistical Yearbook”, “Shanghai Industrial Transportation Energy Statistics Yearbook”, etc.
In 1995-2011, the paper used natural geography, social, economic and environmental data in Pudong new area as the foundation, with the help of various products and elements of emergy conversion to analysis all kinds of eco-economy system emergy and determine each objective value. 3.2 Research steps The basic procedure of emergy synthesis for the new area ecosystem can be summarized as following four steps: (1) confirming the system boundary and collecting data and drawing the emergy system diagram as shown in Fig.1, (2) preparing the emergy accounting table to analyze major energy, materials, goods and services flows, (3) setting up the emergy-based indicators and calculating their values as shown in Table 1, and (4) result analysis for the new area eco-economy system.
The dynamics of the Emergy Index for Sustainable Development (EISD) also indicated a marked reduction in the sustainability of the Pudong eco-economy system, with a 22% decline during the study period (as compared with the 12% decline in ESI), which showed that with the economic development, the Pudong new area had high environment pressure, and the sustainability of the system would decline constantly.
Online since: December 2012
Authors: Ushasta Aich, Amit Kumar Pal, Dipak Laha, Simul Banerjee
Response surface methodology (RSM) The general expression for a central composite design is described by the model (2) The least square estimates, b, of the parameters, of the model are obtained in the usual way (3) The analysis of variance are then computed from Total (4) Regression (5) Pure Error (6) Lack of Fit = Total SS – Regression SS – Pure Error SS (7) Based on the data available, the b values as obtained from the equation 3 are estimated.
Table 1 ANOVA for MRR Sources Degrees of freedom Sum of squares Mean square F value Tabulated F value 1% 5% Regression 9 410.34 45.593 246.451 10.16 4.77 Lack of fit 5 1.042 0.208 1.13 10.97 5.05 Pure error 5 0.923 0.185 Total 19 412.31 Goodness of fit R2 = 99.52% Table 2 ANOVA for Ra Sources Degrees of freedom Sum of squares Mean square F value Tabulated F value 1% 5% Regression 9 65.7173 7.3019 43.079 10.16 4.77 Lack of fit 5 0.2978 0.0596 0.35 10.97 5.05 Pure error 5 0.8477 0.1695 Total 19 66.8628 Goodness of fit R2 = 98.29% Thus on analyzing the data the estimated response surface equations as obtained in absolute values of parameters after transformation are enumerated below.
Estimated response surface equation for material removal rate in mm3/min MRR = 5.0215 + 5.533*I + 1.4115*to – 1.5694*tf + 2.4193*I2 – 0.7371*to2 – 0.0112*tf2 + 1.4449*I*to – 1.6467*I*tf + 0.1022*to*tf (8) Estimated response surface equation for surface roughness parameter Ra in micron Ra = 4.841 + 2.403*I + 0.564*to + 0.098*tf – 0.0691*I2 – 0.0641*to2 + 0.0859*tf2 + 0.7562*I*to + 0.0663*I*tf – 0.0762*to*tf (9) The models are then tested for their accuracy with a set of 6 data points.
In the present study a set of 1210 initial points are chosen randomly in the search space and the different criteria are set as follows: initial starting temperature = 250oC, temperature reduction parameter = 0.975, number of iteration at a particular temperature = 100 and accuracy = 0.05.
Current (A) Pulse on time (µs) Pulse off time (µs) MRR (mm3/min) Ra (µm) 1 3.0184 117.7043 138.1988 1.9066 2.3695 2 3.5414 122.2277 66.8499 2.4044 2.9788 3 3.9108 129.9980 59.1269 3.0015 3.3863 4 4.2681 137.0140 51.0040 3.7363 3.7689 5 4.8298 140.4917 52.9878 4.7302 4.2628 6 5.2157 106.4278 62.7714 4.9163 4.3755 7 5.8305 91.0492 60.4837 5.6937 4.6369 8 6.5296 84.3491 51.2879 7.0176 4.9277 9 7.5031 70.7896 51.7327 7.9744 5.1183 10 7.4693 72.0900 50.4350 8.0657 5.1309 11 8.9898 65.9924 50.0696 10.0303 5.4970 12 10.5440 64.0422 50.9034 12.0419 5.8511 13 11.6913 77.9043 54.6569 14.2547 6.5163 14 11.9084 149.9033 56.1071 16.8756 7.8546 Based on the available parameter settings in the EDM machine, a small comparison is made between the Pareto optimal points and experimental data points and shown in Table 4.
Online since: November 2012
Authors: Bichitra Nandi Ganguly
Given an input from the experimental condition of positron life time measurement /or angular correlation data, the model can be tested.
Armed with the modified description of the ‘bubble model’, it has been possible to fit the life time data for various types of liquids, to achieve a more simplified expression, i.e. tpick –off =1.88R-5.07.
Curvature effect of surface tension (ST) for small bubble, taking finite size effect of Ps in the diffused boundary model, with the modified relation ship : tpick –off =1.88R-5.07 vide [5] Liquids S T( bulk) (dynes/cm) S T g effective (dynes/cm) % correction due to curvature effect Fitting Life time data Radius R (Å) U0 (eV) n- pentane 15.32 14.81 3.32 5.04 1.19 n- hexane 17.74 17.14 3.38 4.86 1.26 Benzene 28.22 27.62 2.12 4.33 1.56 Water 72.10 69.21 4.01 3.44 2.16 Propanol 23.32 22.60 3.08 4.53 1.56 Butanol 24.93 24.17 3.04 4.45 1.65 Octanol 27.10 26.22 3.24 4.37 1.62 Methanol 22.12 21.15 4.38 4.63 1.10 It is also interesting to observe a posteriori that the value of D, is generally small being 0.15 Å and what is more relevant, (D/R) ~0.03<<1. which accords with the Tolman type relationship.
Thus, the positronium formation process which essentially requires free diffusion of quassi- free electrons, and slowed down e+, if hindered or removed from the scene, an inhibition / or drastic reduction in positronium formation results.
[6] The experimental data included are partly from our laboratory at SINP vide thesis : Debarshi Gangopadhyay (2002) Surface tension using Du Nouy Tensiometer and slow fast coincidence technique of positron life time spectrometer and also from H.
Online since: June 2014
Authors: Zhi Yuan Wang, Hong Zhang, Ya Jun Wang
At present in the high grade highway, first-class highway and second-class highway the common measure to prevent or mitigate the vehicle bump disease is set approach slab in bridge heads, the basic working mechanism is that abutment and embankment at convergence produce larger settlement since the flexible body embankment and led to longitudinal pavement mutation ( Vehicle Bump stairs , etc. ), by setting approach slab to ease the transition , control the change of pavement longitudinal slope within the allowable range , making the stiffness of bridge pavement connection stable and continuous transition , so as to achieve the maximum reduction or elimination of bridgehead vehicle bump.
Meet between functions y and variables x relationship: , can be obtained by regression analysis (1) the Actual observed subsidence regression analysis (2) Settlement regression analysis the projected work after projecting It should be noted that the regression analysis should be supported by a large number of accurate experimental data in the study of this project, in this research project , there are too few experimental data points .
Similarly, regression analysis can be obtained (1) The Actual observed subsidence regression analysis (2) Settlement regression analysis the projected work after projecting As can be seen from Table 1-6,the regression analysis should be supported by a large number of accurate experimental data in the study of this project, in this research project , there are too few experimental data points .
Online since: February 2012
Authors: Chun Li Lei, Zhi Yuan Rui, Jun Liu, Li Na Ren
Examples of successful thermal errors reduction with the aid of error compensation techniques have been demonstrated in both research laboratories and industrial facilities.
Considering the effect of the historical data on the present thermal deformation, displacement value in the axial direction was also selected as independent variables.
This experiment spanned 60 minutes, the first 30 minutes of data was used for model training and the remaining 30 minutes of data was used for model verification.
Results are compared in Figures 4 for the expansion of the thermal elongation and the residual of the second 30 minutes data is 0.6μm, which is shown that the derived thermal error model is reasonably robust in the sense of linear extrapolation.
Online since: February 2013
Authors: Zhou Wan, Xing Zhi Liao, Xin Xiong, Jin Chuan Han
Firstly, in the whole data set, the number of extrema and the number of zero-crossings must either equal or differ at most by one; Secondly, at any point, the mean value of the upper and lower envelope is zero.
The fault diagnosis analysis of rolling bearing In order to validate the effectiveness of the method proposed in this paper, In research, we have adopted drive end bearing fault data collected from bearing fault simulation experiment platform of electrical engineering lab in Case Western Reserve University, USA.
This paper adopted a method that combined five-spot triple smoothing approach, wavelet de-noising and filtering process, and the smoothing times are 20, the wavelet ‘sym4’ was used for decomposing the signal into two layers in the process of wavelet de-noising, and soft threshold method was applied to perform noise-reduction, then filtering process was conducted to dispose of the signal after de-noising.
Ensemble empirical mode decomposition: a noise-assisted data analysis method [J].
Advances in Adaptive Data Analysis, 2009; 1(1): 1-4l
Online since: September 2008
Authors: Fabrizio Roccaforte, Filippo Giannazzo, Vito Raineri, Ferdinando Iucolano, Salvatore Di Franco, Valeria Puglisi
By the linear fit of the data an effective barrier height of 0.74 eV and a Richardson's constant of 4×10-3Acm-2K -2 were extracted.
The extrapolation at n=1 (ideal case) of the barrier       =            Φ − = nkT qV I nkT qV kT q TAAI s B exp exp exp* 2 (1) Fig. 1: (a) Forward I-V characteristics of Pt/GaN Schottky contacts at different temperatures; (b) Richardson's plot determined from the data reported in (a). 24 27 30 33 36 39 -40 -38 -36 -34 -32 -30 (b) ln(Is/T 2 ) 1/kT (eV -1 ) 0.0 0.4 0.8 1.2 10 -10 10 -8 10 -6 10 -4 10 -2 175°C 25°C (a) Current (A) Forward Voltage (V) height is ΦB0= 1.21 eV, which can be regarded as the barrier height for the ideal homogeneous Pt/GaN contact.
The degree of inhomogeneity of the barrier can be quantitatively described by the standard deviation (σΦB=0.11 eV) of the Gaussian curve fit of the data.
The improved barrier homogeneity after annealing can be due to a change of the metal/GaN interface intimate properties (reduction of the interface states density, removal of a residual oxide layer, interfacial reaction, etc.) and is object of further investigations.
The extrapolation of the barrier height at n=1 (ideal case) is ΦB0= 1.21 eV 1.08 1.10 1.12 1.14 1.16 1.18 0.92 0.96 1.00 1.04 1.08 1.12 experimental data fit linear Barrier height ΦB (eV) Ideality factor n Fig. 3 : Distribution of the barrier height values determined by the local I-V measurements 0.6 0.7 0.8 0.9 1.0 1.1 1.2 0 5 10 15 20 25 30 Counts Local Barrier Height (eV) Fig. 4: Surface morphology of the bare GaN surface determined by AFM.
Online since: October 2006
Authors: Anatoly M. Strel'chuk, G. Kholuyanov, Nikita B. Strokan, Alexander M. Ivanov, Evgenia V. Kalinina, Alexander A. Lebedev
Lately, the progress toward commercial growth of pure SiC epitaxial layers made it possible to obtain new data on the effect of irradiation on starting material and some characteristics of SiC device structures [7-9].
Such studies provided information on mechanisms of failures and threshold radiation doses, which bring about variations in the device characteristics and degradation of devices as well as confirmed the earlier data on high radiation hardness of SiC.
DLTS data were obtained at a frequency of 10 kHz in the temperature range of 80-400 K and 80-700 K for SBs and ID diodes, respectively.
Results and discussion According to the experimental PL, DLTS and CV data, the neutrons, protons, electrons and high energy ions introduced very similar defect centers in epitaxial 4H and 6H-SiC layers, some of which were partly annealed at high temperatures.
The transient radiation response of the SiC diodes demonstrated sufficient benefit as compared to Si devices, the reduction of ionizing current was in the range from 5 to 7 times under the same dose rate, related to both the lower carrier generation and carrier lifetime in SiC as compared with Si [12].
Online since: July 2011
Authors: Yong Gang Yang
Actually, the print-through caused by ink penetration is also due to opacity reduction in the printing area on paper [7-9].
Paper proofing and relevant data testing Because the alleviation of offset print-through could be achieved by properly decreasing printing pressure and increasing printing speed [5], thus 3 sets of printing condition were adapted, which was (625 N,0.4 m/s), (725 N,0.3 m/s), (825 N,0.2 m/s).
In Table 1, data variation among the three factors revealed this law.
Relationships between paper PTR value and print-through property Fig. 2 and Fig. 3 are built up according to the data from Table 1, Table 2.
Also, it is the first time to bring PTR value to predict print-through property for paper print, the prejudging model is built up, and the data show when PTR value is lower than 72%, the print-through problems will be more serious with the falling PTR.
Online since: June 2011
Authors: Syed Jawid Askari, Li Jing Xie, S.I. Butt, U. Umer, S.N. Danish
The analog force signals from the charge amplifier were then passed through a data acquisition card.
A PC-based data acquisition program (Dynoware) was used to acquire the sampled data and save for analysis.
These terms are determined from experiment results and can include data over a wide range of strain rates and temperatures.
Reducing the feed rate to 0.15mm/rev leads to reduction in both cutting and thrust forces by 40% and 60% respectively.
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