The airborne electromagnetic （AEM） method has a high sampling rate and survey flexibility. However, traditional numerical modeling approaches must use high-resolution physical grids to guarantee modeling accuracy, e...The airborne electromagnetic （AEM） method has a high sampling rate and survey flexibility. However, traditional numerical modeling approaches must use high-resolution physical grids to guarantee modeling accuracy, especially for complex geological structures such as anisotropic earth. This can lead to huge computational costs. To solve this problem, we propose a spectral-element （SE） method for 3D AEM anisotropic modeling, which combines the advantages of spectral and finite-element methods. Thus, the SE method has accuracy as high as that of the spectral method and the ability to model complex geology inherited from the finite-element method. The SE method can improve the modeling accuracy within discrete grids and reduce the dependence of modeling results on the grids. This helps achieve high-accuracy anisotropic AEM modeling. We first introduced a rotating tensor of anisotropic conductivity to Maxwell＇s equations and described the electrical field via SE basis functions based on GLL interpolation polynomials. We used the Galerkin weighted residual method to establish the linear equation system for the SE method, and we took a vertical magnetic dipole as the transmission source for our AEM modeling. We then applied fourth-order SE calculations with coarse physical grids to check the accuracy of our modeling results against a 1D semi-analytical solution for an anisotropic half-space model and verified the high accuracy of the SE. Moreover, we conducted AEM modeling for different anisotropic 3D abnormal bodies using two physical grid scales and three orders of SE to obtain the convergence conditions for different anisotropic abnormal bodies. Finally, we studied the identification of anisotropy for single anisotropic abnormal bodies, anisotropic surrounding rock, and single anisotropic abnormal body embedded in an anisotropic surrounding rock. This approach will play a key role in the inversion and interpretation of AEM data collected in regions with anisotropic geology.展开更多
In this paper, the classical risk process perturbed by diffusion is generalized by allowing for “size fluctuation” and the ruin probability for this new model is discussed.
Objective To explore the effect of Daicong solu tion(DCS)on aged rats dementia model.Method The experiment used22-month old rats whose basal nuclei was destroyed by bilateral electrolytic method as model for aged rats...Objective To explore the effect of Daicong solu tion(DCS)on aged rats dementia model.Method The experiment used22-month old rats whose basal nuclei was destroyed by bilateral electrolytic method as model for aged rats dem entia.They were treated with DCS for a month.Then the level of superox ide dismutase(SOD),lipid peroxide(LPO),monoamine oxidase(MAO)and cholinesterase(CHE)in the serum was measured.Result Compared with the control,the activ ity of SOD increased markedly(P <0.01),the content of LOP and activity MAO and CHE were decreased(P <0.01).Conclusion DCS is effective in treating the aged dementia.展开更多
[Objective] The study aimed to assess the health state of rivers by using fuzzy matter-element model.[Method] Based on fuzzy matter-element analysis theory,the assessment model of river health was established,then a m...[Objective] The study aimed to assess the health state of rivers by using fuzzy matter-element model.[Method] Based on fuzzy matter-element analysis theory,the assessment model of river health was established,then a modified method to calculate the superior subordinate degree was put forward according to Hamming distance.Afterwards,a multi-level evaluation model,which contained the assessment indicators about hydrological features,ecological characteristics,environmental traits and service function,was set up based on this method above.Finally,the model was applied in the health assessment of Qinhuai River.[Result] The health state of Qinhuai River was at medium level.This assessment result was consistent with that of comprehensive index method,and it showed that the multi-level fuzzy matter-element model was effective in the assessment of river health.[Conclusion] The research provided an effective method to evaluate the state of river health.展开更多
This article discusses the problem of the detection of influential cases in nonlinear reproductive dispersion models (NRDM). A diagnostic based on case\|deletion approach in estimating equations is proposed. The relat...This article discusses the problem of the detection of influential cases in nonlinear reproductive dispersion models (NRDM). A diagnostic based on case\|deletion approach in estimating equations is proposed. The relationships between the generalized leverage defined by Wei et al. in 1998, statistical curvature, and the local influence of the response vector perturbations are investigated in NRDM. Two numerical examples are given to illustrate the results.展开更多
Objective Explore the effect of Daicong solution on immune funct io n for aged rat dem entia model.Method Basal nuclei of 22months old rat being destroyed by bilateral electrolytic method have been established animal ...Objective Explore the effect of Daicong solution on immune funct io n for aged rat dem entia model.Method Basal nuclei of 22months old rat being destroyed by bilateral electrolytic method have been established animal dementia model of learning and memory func-tion.Lymphocyte proliferation was tested by 3 H-TdR incorporation methods.Spleen cell producing antibody function w as d etermined by spleen cell mediated red cell hemolysis method.Result Daicong solu tion has remarkably increased lymphocyte proliferation fu nction,compared with model groups(P <0.01).It has strengthened the producing a ntibody functi on of the spleen cell t oo,compared with model group(P <0.01).Conclusio n Daicong solution has marked increased functions of cellular and humoral immun ity for dementia animal model.Which is heavier than that of Naofukang.展开更多
为分析寄生参数对开关过程中碳化硅(Si C)MOSFET栅源极电压的影响,首先建立了基于同步Buck变换器的Si C MOSFET开通和关断过程的数学模型;然后通过仿真和实验结果对比,验证了寄生参数带来的影响;最后分析了开关过程中各寄生参数对Si C M...为分析寄生参数对开关过程中碳化硅(Si C)MOSFET栅源极电压的影响,首先建立了基于同步Buck变换器的Si C MOSFET开通和关断过程的数学模型;然后通过仿真和实验结果对比,验证了寄生参数带来的影响;最后分析了开关过程中各寄生参数对Si C MOSFET栅源极电压的影响。展开更多
基金financially supported by the Key Program of National Natural Science Foundation of China(No.41530320)China Natural Science Foundation for Young Scientists(No.41404093)+1 种基金Key National Research Project of China(Nos2016YFC0303100 and 2017YFC0601900)China Natural Science Foundation(No.41774125)
文摘The airborne electromagnetic （AEM） method has a high sampling rate and survey flexibility. However, traditional numerical modeling approaches must use high-resolution physical grids to guarantee modeling accuracy, especially for complex geological structures such as anisotropic earth. This can lead to huge computational costs. To solve this problem, we propose a spectral-element （SE） method for 3D AEM anisotropic modeling, which combines the advantages of spectral and finite-element methods. Thus, the SE method has accuracy as high as that of the spectral method and the ability to model complex geology inherited from the finite-element method. The SE method can improve the modeling accuracy within discrete grids and reduce the dependence of modeling results on the grids. This helps achieve high-accuracy anisotropic AEM modeling. We first introduced a rotating tensor of anisotropic conductivity to Maxwell＇s equations and described the electrical field via SE basis functions based on GLL interpolation polynomials. We used the Galerkin weighted residual method to establish the linear equation system for the SE method, and we took a vertical magnetic dipole as the transmission source for our AEM modeling. We then applied fourth-order SE calculations with coarse physical grids to check the accuracy of our modeling results against a 1D semi-analytical solution for an anisotropic half-space model and verified the high accuracy of the SE. Moreover, we conducted AEM modeling for different anisotropic 3D abnormal bodies using two physical grid scales and three orders of SE to obtain the convergence conditions for different anisotropic abnormal bodies. Finally, we studied the identification of anisotropy for single anisotropic abnormal bodies, anisotropic surrounding rock, and single anisotropic abnormal body embedded in an anisotropic surrounding rock. This approach will play a key role in the inversion and interpretation of AEM data collected in regions with anisotropic geology.
文摘In this paper, the classical risk process perturbed by diffusion is generalized by allowing for “size fluctuation” and the ruin probability for this new model is discussed.
文摘Objective To explore the effect of Daicong solu tion(DCS)on aged rats dementia model.Method The experiment used22-month old rats whose basal nuclei was destroyed by bilateral electrolytic method as model for aged rats dem entia.They were treated with DCS for a month.Then the level of superox ide dismutase(SOD),lipid peroxide(LPO),monoamine oxidase(MAO)and cholinesterase(CHE)in the serum was measured.Result Compared with the control,the activ ity of SOD increased markedly(P <0.01),the content of LOP and activity MAO and CHE were decreased(P <0.01).Conclusion DCS is effective in treating the aged dementia.
基金Supported by National Natural Science Foundation of China (50879018)Innovation Project of Jiangsu Province in 2008+1 种基金Special Fee for Scientific Research in Public Welfare Industry of Ministry of Water Resources (201001030)Special Fee of Key National Laboratories (1069-50987112)
文摘[Objective] The study aimed to assess the health state of rivers by using fuzzy matter-element model.[Method] Based on fuzzy matter-element analysis theory,the assessment model of river health was established,then a modified method to calculate the superior subordinate degree was put forward according to Hamming distance.Afterwards,a multi-level evaluation model,which contained the assessment indicators about hydrological features,ecological characteristics,environmental traits and service function,was set up based on this method above.Finally,the model was applied in the health assessment of Qinhuai River.[Result] The health state of Qinhuai River was at medium level.This assessment result was consistent with that of comprehensive index method,and it showed that the multi-level fuzzy matter-element model was effective in the assessment of river health.[Conclusion] The research provided an effective method to evaluate the state of river health.
文摘This article discusses the problem of the detection of influential cases in nonlinear reproductive dispersion models (NRDM). A diagnostic based on case\|deletion approach in estimating equations is proposed. The relationships between the generalized leverage defined by Wei et al. in 1998, statistical curvature, and the local influence of the response vector perturbations are investigated in NRDM. Two numerical examples are given to illustrate the results.
文摘Objective Explore the effect of Daicong solution on immune funct io n for aged rat dem entia model.Method Basal nuclei of 22months old rat being destroyed by bilateral electrolytic method have been established animal dementia model of learning and memory func-tion.Lymphocyte proliferation was tested by 3 H-TdR incorporation methods.Spleen cell producing antibody function w as d etermined by spleen cell mediated red cell hemolysis method.Result Daicong solu tion has remarkably increased lymphocyte proliferation fu nction,compared with model groups(P <0.01).It has strengthened the producing a ntibody functi on of the spleen cell t oo,compared with model group(P <0.01).Conclusio n Daicong solution has marked increased functions of cellular and humoral immun ity for dementia animal model.Which is heavier than that of Naofukang.
