Iran sits on a region with a high intrinsic level of seismic activity due to its tectonic setting.Through statistical examination of the earthquakes listed in the catalogue from International Institute of Earthquake E...Iran sits on a region with a high intrinsic level of seismic activity due to its tectonic setting.Through statistical examination of the earthquakes listed in the catalogue from International Institute of Earthquake Engineering and Seismology(IIEES),this research attempted to calculate some seismicity factors and find correlation between them.A preliminary analysis indicated changes in theb-value of the Gutenberg-Richter relationship over the study region.Thus,the study area was divided into five zones(Alborz,Zagros,Azerbaijan,Central and East)andb-value was computed for each zone.Considering faulting mechanism styles and theb-values in the region,it was found that the lowestb-values belong to the thrust events and strike-slip faulting earthquakes have intermediate values.These findings support previous studies.Furthermore,results ofb-value calculation were used for the estimation of accumulated differential stresses(σ1–σ2)over each zone.Overall,theb-value for Iran is averagely low which signifies the high stress tectonic regime in this region.Also,by having calculated fractal dimension(D)in each zone,a correlation obtained showing that in Iran region,theb-value correlates to fractal dimension byD=4.2b–2 relation which does not support Aki's(1981)speculation ofD=3b/c.展开更多
In order to monitor and forecast the deformation of the brick-concrete building, by taking a brick-concrete building as research object, fiber grating sensors were used to collect the monitoring data and double logari...In order to monitor and forecast the deformation of the brick-concrete building, by taking a brick-concrete building as research object, fiber grating sensors were used to collect the monitoring data and double logarithmic curve of limit value characteristic and monitoring data were obtained based on the fractal theory. Constant dimension fractal method cannot be used to analyze the data directly. With the method of variable dimension fractal, we accumulate data, and the double logarithmic curve is smooth. Piecewise fractal dimensions are close. The outer interpolation method is used to calculate the fractal dimension of the next point and then back calculate the vertical displacement. The relative errors are calculated by comparing the forecast values and monitoring values, and the maximum relative error is 5.76%. The result shows that the fractal theory is suitable to use in the forecast of the deformation and the accuracy is good.展开更多
Rheological tests for raw and conditioned activated sludge （AS） or anaerobic digested sludge （ADS） show that power-law relationships can be used to describe the evolution of several rheological parameters, i.e., l...Rheological tests for raw and conditioned activated sludge （AS） or anaerobic digested sludge （ADS） show that power-law relationships can be used to describe the evolution of several rheological parameters, i.e., limiting viscosity （η∞）, yield stress （τy）, cohesion energy of the sludge network （Ec）, and storage modulus （G＇）, with total suspended solid （TSS） content in raw and conditioned sludge. A gel-like structure that behaves similar to weak-link flocs/aggregates was observed in AS and ADS. As derived from the double-logarithmic plots of G＇-TSS content, the mass fractal dimensions of the raw and conditioned AS or ADS flocs/aggregates were 2.70 and 2.53 or 2.85 and 2.79, respectively. The theological tests also indicate that both polymer conditioning and increased TSS content led to improved elastic behavior, cohesion energy, and yield stress of the sludge network, as well as expanded the corresponding linear viscoelastic range. The porosity of AS or ADS flocs/aggregates will be improved by polymer conditioning.展开更多
文摘Iran sits on a region with a high intrinsic level of seismic activity due to its tectonic setting.Through statistical examination of the earthquakes listed in the catalogue from International Institute of Earthquake Engineering and Seismology(IIEES),this research attempted to calculate some seismicity factors and find correlation between them.A preliminary analysis indicated changes in theb-value of the Gutenberg-Richter relationship over the study region.Thus,the study area was divided into five zones(Alborz,Zagros,Azerbaijan,Central and East)andb-value was computed for each zone.Considering faulting mechanism styles and theb-values in the region,it was found that the lowestb-values belong to the thrust events and strike-slip faulting earthquakes have intermediate values.These findings support previous studies.Furthermore,results ofb-value calculation were used for the estimation of accumulated differential stresses(σ1–σ2)over each zone.Overall,theb-value for Iran is averagely low which signifies the high stress tectonic regime in this region.Also,by having calculated fractal dimension(D)in each zone,a correlation obtained showing that in Iran region,theb-value correlates to fractal dimension byD=4.2b–2 relation which does not support Aki's(1981)speculation ofD=3b/c.
文摘In order to monitor and forecast the deformation of the brick-concrete building, by taking a brick-concrete building as research object, fiber grating sensors were used to collect the monitoring data and double logarithmic curve of limit value characteristic and monitoring data were obtained based on the fractal theory. Constant dimension fractal method cannot be used to analyze the data directly. With the method of variable dimension fractal, we accumulate data, and the double logarithmic curve is smooth. Piecewise fractal dimensions are close. The outer interpolation method is used to calculate the fractal dimension of the next point and then back calculate the vertical displacement. The relative errors are calculated by comparing the forecast values and monitoring values, and the maximum relative error is 5.76%. The result shows that the fractal theory is suitable to use in the forecast of the deformation and the accuracy is good.
基金supported by the Fundamental Research Funds for the Central Universities (No. JC2011-1,TD2010-5)the National Natural Science Foundation of China (No. 51078035,21177010)+2 种基金the Ph.D. Programs Foundation of the Ministry of Education of China (No.20100014110004)the High-Tech Research and Development Program (863) of China (No. 2007AA06Z301)the Major Projects on the Control and Rectificationof Water Body Pollution (No. 2008ZX07422-002-004,2008ZX07314-006)
文摘Rheological tests for raw and conditioned activated sludge （AS） or anaerobic digested sludge （ADS） show that power-law relationships can be used to describe the evolution of several rheological parameters, i.e., limiting viscosity （η∞）, yield stress （τy）, cohesion energy of the sludge network （Ec）, and storage modulus （G＇）, with total suspended solid （TSS） content in raw and conditioned sludge. A gel-like structure that behaves similar to weak-link flocs/aggregates was observed in AS and ADS. As derived from the double-logarithmic plots of G＇-TSS content, the mass fractal dimensions of the raw and conditioned AS or ADS flocs/aggregates were 2.70 and 2.53 or 2.85 and 2.79, respectively. The theological tests also indicate that both polymer conditioning and increased TSS content led to improved elastic behavior, cohesion energy, and yield stress of the sludge network, as well as expanded the corresponding linear viscoelastic range. The porosity of AS or ADS flocs/aggregates will be improved by polymer conditioning.
