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1.

Accurate prediction of the liquefaction-induced settlement (\({S}_{\mathrm{lc}}\)) is an essential requirement for a good design of buildings resting on liquefiable ground and subjected to seismic shake. However, prediction of the \({S}_{\mathrm{lc}}\) is not straightforward process and it requires advanced soil models and calibrated soil parameters that are not readily available for designers/practitioners. In addition, the available empirical models to estimate the \({S}_{\mathrm{lc}}\) have been developed using either classical regression analysis or multivariate adaptive regression splines and such techniques produce complicated models. Also, these empirical models have been developed utilizing results of numerical modelling. To overcome these limitations, novel model has been developed in this paper utilizing robust regression analysis driven by artificial intelligence called the evolutionary polynomial regression analysis. The new model has been developed using centrifuge results (real laboratory measurements) and can be easily used to accurately estimate the liquefaction induced settlement. The developed model scored a mean absolute error, root mean square error, mean, standard deviation of the predicted to measured values, coefficient of determination, \(a20 - \mathrm{index}\), and EPR coefficient of determination of 2.12 cm, 2.84 cm, 1.06, 0.19, 0.98, 0.77, and 97%, respectively, for the learning data and 1.73 cm, 3.31 cm, 0.99, 0.17, 0.97, 0.75, and 97%, respectively, for the examination data. The developed model has also been used in a parametric study to provide an insight into the sensitivity of the \({S}_{\mathrm{lc}}\) to the foundation width, building height, pressure applied on the foundation, thickness and relative density of the liquefiable layer, and earthquake intensity. The results obtained from the parametric study are reasonable and in agreement with previous studies in the literature. Thus, the developed model can be employed to optimize designs and to reduce design costs as it does not require complicated analyses and/or expensive computational facilities.

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We present uniaxial tensile test results for 30–50 nm thick freestanding aluminum films. Young’s modulus and ductility were found to decrease monotonically with grain size. Reverse Hall–Petch behavior was observed with no appreciable room temperature creep. Non-linear elasticity with small irreversible deformation was observed for 50 nm thick specimens.  相似文献   
4.
A two-dimensional cross-section finite difference model is presented to simulate density dependent leachate migration in leaky aquifers. Unlike existing models, a new approach is adopted to couple the groundwater-flow equation and the hydrodynamic dispersion equation with the elimination of the intermediate step of calculating velocities. The concept of the reference density is employed, permitting increased accuracy (over pressure-based models) in the representation of the transport process. The model is then used to study the effect of several hydraulic and transport parameters on the flow pattern and plume migration which are found to be very sensitive to most of these parameters. Equiconcentration and equipotential lines are overlapped to provide a better understanding of the coupling effect.  相似文献   
5.
Enteric viral infections of calves and passive immunity   总被引:6,自引:0,他引:6  
At least eight viruses have been identified, four within the last 5 yr, that produce diarrhea and pathological intestinal lesions in experimentally inoculated calves. Coronavirus and rotavirus frequently are associated with the neonatal calf diarrhea syndrome, but the etiologic role of the newly identified viruses is undefined. All diarrheal viruses replicate within small intestinal epithelial cells, resulting in variable degrees of villous atrophy. Immunity against these viral infections, therefore, must be directed toward protection of the susceptible intestinal epithelial cells. Because most of these viral infections occur in calves less than 3 wk of age, passive lactogenic immunity within the gut lumen plays an important role in protection. This report reviews methods of boosting rotavirus antibody responses in bovine mammary secretions and analyses of passive and active immunity in calves supplemented with colostrum and challenged by rotavirus. Results indicate rotavirus immunoglobulin G1 antibodies in colostrum and milk were elevated after intramuscular and intramammary vaccination of pregnant cows with an Ohio Agricultural Research and Development Center rotavirus vaccine but not after intramuscular immunization with a commercial rota-coronavirus vaccine. Feeding colostrum from intramuscular plus intramammary immunized cows to newborn calves challenged by rotavirus prevented diarrhea and shedding of rotavirus.  相似文献   
6.
A. I. Alkhamis  S. A. Sherif 《Energy》1992,17(12):1165-1172
This paper deals with feasibility studies for a solar-assisted heating system for the University of Miami's Aquatic Center using the simulation program TRNSYS. The Aquatic Center is composed of an outdoor olympic size swimming pool and locker room building. The solar heating is accomplished by employing hot water generated by heat exchange with the solar collector working fluid. Two thermal storage tanks are employed for the collector and domestic use. The performance of the system is analyzed from both thermodynamic and economic standpoints and general conclusions are reached.  相似文献   
7.
This work gives an overview of the different developments for silicon germanium (Si1−xGex) from a MEMS post-processing perspective. First, the maximum processing temperature that does not introduce any damage or degradation into the standard characteristics of the CMOS driving electronics is specified. Then, the optimal type of silicon and germanium gas sources and deposition technique that results in an economical process are identified. Next, the selection criteria for a low thermal budget doping method and doping species are discussed. Finally, the advantage and disadvantage for the different approaches implemented for enhancing the physical properties of poly Si1−xGex at a CMOS backend compatible temperature are highlighted. It is shown that the optimal method depends on the application requirements and the CMOS technology used for realizing the driving electronics.  相似文献   
8.
We consider penetration of magnetic flux in the rare earth ceramic superconductors within the framework of a generalized Ginzburg-Landau theory, based on the coexistence of antiferromagnetism and superconductivity. We study vortex structure produced for a magnetic field close to . We make a new prediction that may serve to test the theory experimentally.  相似文献   
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Journal of Inorganic and Organometallic Polymers and Materials - Surface oxygen of oxide catalyst has low coordination number; they are negatively charged. Surface oxygen can act active site for...  相似文献   
10.
Some ferrocene containing aromatic azo polyesters were prepared by condensing 1,1-ferrocenedicarbonyl chloride with different azo groups containing aromatic diols, which were synthesized by diazotization coupling reaction from aromatic diamines. The polymeric products were separated as two portions on the basis of their solubility and subsequently characterized by their elemental analysis and FTIR spectral studies. Thermal properties of the products were measured by differential scanning calorimetry and thermogravimetry and the activation energies of pyrolysis were calculated using Horowitz and Metzger's method. The molecular weights of the soluble portions were determined by gel permeation chromatography (GPC) and these portions were also characterized by their inherent viscosities and UV-Vis spectroscopic studies.  相似文献   
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