In this paper, the general calculation formulas of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 are obtained, and the recurrence relation of different power order radial matrix eleme...In this paper, the general calculation formulas of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 are obtained, and the recurrence relation of different power order radial matrix elements are also derived.展开更多
A new favorable iterative algorithm named as PBiCGSTAB (preconditioned bi-conjugate gradient stabilized) algorithm is presented for solving large sparse complex systems. Based on the orthogonal list, the special tec...A new favorable iterative algorithm named as PBiCGSTAB (preconditioned bi-conjugate gradient stabilized) algorithm is presented for solving large sparse complex systems. Based on the orthogonal list, the special technique of only storing non-zero elements is carried out. The incomplete LU factorization without fill-ins is adopted to reduce the condition number of the coefficient matrix. The BiCGSTAB algorithm is extended from the real system to the complex system and it is used to solve the preconditioned complex linear equations. The locked-rotor state of a single-sided linear induction machine is simulated by the software programmed with the finite element method and the PBiCGSTAB algorithm. Then the results are compared with those from the commercial software ANSYS, showing the validation of the proposed software. The iterative steps required for the proposed algorithm are reduced to about one-third, when compared to the BiCG method, therefore the algorithm is fast.展开更多
A higher order boundary dement method (HOBEM) is implemented for wave-current action on structures. The freeterm coefficient and Cauchy principal value ( GPV) integrals are computed by direct methods. Numerical ex...A higher order boundary dement method (HOBEM) is implemented for wave-current action on structures. The freeterm coefficient and Cauchy principal value ( GPV) integrals are computed by direct methods. Numerical experiments are carried out to validate the computation of free-term coefficient and GPV integrals. The results show that the computation precision of free-term coefficient is very high for various bodies, even with edges and corners, and the convergence speed is fast for CPV integrals for different meshes. The comparison of the second order mean drift force due to wave-current action on a uniform cylinder is made with an analytic solution. It is found that good agreement exists between the present calculation and the analytic solutions. Finally, the numerical code is applied for computing wave-current action on Snorrc TLP.展开更多
In order to investigate the viscoelastic performance of asphalt mastics, a micro-mechanical model for asphalt mastics was built by applying Burgers model to discrete element simulation and constructing Burgers contact...In order to investigate the viscoelastic performance of asphalt mastics, a micro-mechanical model for asphalt mastics was built by applying Burgers model to discrete element simulation and constructing Burgers contact model. Then the numerical simulation of creep tests was conducted, and results from the simulation were compared with the analytical solution for Burgers model. The comparision showed that the two results agreed well with each other, suggesting that discrete element model based on Burgers model could be employed in the numerical simulation for asphalt mastics.展开更多
Alzheimer’s disease is a severe neuron disease that damages brain cells which leads to permanent loss of memory also called dementia.Many people die due to this disease every year because this is not curable but earl...Alzheimer’s disease is a severe neuron disease that damages brain cells which leads to permanent loss of memory also called dementia.Many people die due to this disease every year because this is not curable but early detection of this disease can help restrain the spread.Alzheimer’s ismost common in elderly people in the age bracket of 65 and above.An automated system is required for early detection of disease that can detect and classify the disease into multiple Alzheimer classes.Deep learning and machine learning techniques are used to solvemanymedical problems like this.The proposed system Alzheimer Disease detection utilizes transfer learning on Multi-class classification using brain Medical resonance imagining(MRI)working to classify the images in four stages,Mild demented(MD),Moderate demented(MOD),Non-demented(ND),Very mild demented(VMD).Simulation results have shown that the proposed systemmodel gives 91.70%accuracy.It also observed that the proposed system gives more accurate results as compared to previous approaches.展开更多
Residual stress is one of the factors affecting the machining deformation of monolithic structure parts in the aviation industry. Thus, the studies on machining deformation rules induced by residual stresses largely d...Residual stress is one of the factors affecting the machining deformation of monolithic structure parts in the aviation industry. Thus, the studies on machining deformation rules induced by residual stresses largely depend on correctly and efficiently measuring the residual stresses of workpieccs. A modified layer-removal method is proposed to measure residual stress by analysing the characteristics of a traditional, layer-removal method. The coefficients of strain release are then deduced according to the simulation results using the finite element method (FEM). Moreover, the residual stress in a 7075T651 aluminium alloy plate is measured using the proposed method, and the results are then analyzed and compared with the data obtained by the traditional methods. The analysis indicates that the modified layer-removal method is effective and practical for measuring the residual stress distribution in pre-stretched aluminium alloy plates.展开更多
Quality of life (QOL) is an important topic in social and medical sciences, it has a multidimensional nature and is influenced by many factors. Aim of the Work: In this study we want to assess the impact of cognitive ...Quality of life (QOL) is an important topic in social and medical sciences, it has a multidimensional nature and is influenced by many factors. Aim of the Work: In this study we want to assess the impact of cognitive impairment on the health related quality of life (HR-QOL) of community dwelling non demented elderly. Subject and Method: 115 non demented elderly, 60 years and older recruited from outpatient geriatric clinic at Al Mansoura General Hospital, Dakahlia, Egypt. Each participant underwent, comprehensive geriatric assessment, assessing cognitive function using the mini-mental state examination (MMSE) and montreal cognitive function test, assessing the health related quality of life (HR-QOL) by the RAND-36 health survey. Results: We found that the elderly with impaired cognition by both MMSE and Montreal test were significantly older;the ones with lower education, with more depressive symptoms, had more functional impairment and had lower HR-QOL scores than the elderly with normal cognitive function, after controlling for confounders still cognition was a determinant of HR-QOL. Also by linear correlation coefficient a significant correlation between HR-QOL and age, function, cognition and depression was found. Conclusion: Cognition affects significantly HR-QOL of the elderly, so we can say that interventions targeting cognition in the elderly can significantly improve their QOL.展开更多
In this paper, material properties, geometry parameters and applied loads are assumed to be stochastic, sensitivity computation of structural vibration is presented. The vibration equation of a system is transformed t...In this paper, material properties, geometry parameters and applied loads are assumed to be stochastic, sensitivity computation of structural vibration is presented. The vibration equation of a system is transformed to a static problem by using the Newmark method, and the Taylor expansion stochastic finite element method (TSFEM) is extended for the structural vibration analysis. An example is given, and the calculation results show the validity of the proposed method.展开更多
文摘In this paper, the general calculation formulas of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 are obtained, and the recurrence relation of different power order radial matrix elements are also derived.
文摘A new favorable iterative algorithm named as PBiCGSTAB (preconditioned bi-conjugate gradient stabilized) algorithm is presented for solving large sparse complex systems. Based on the orthogonal list, the special technique of only storing non-zero elements is carried out. The incomplete LU factorization without fill-ins is adopted to reduce the condition number of the coefficient matrix. The BiCGSTAB algorithm is extended from the real system to the complex system and it is used to solve the preconditioned complex linear equations. The locked-rotor state of a single-sided linear induction machine is simulated by the software programmed with the finite element method and the PBiCGSTAB algorithm. Then the results are compared with those from the commercial software ANSYS, showing the validation of the proposed software. The iterative steps required for the proposed algorithm are reduced to about one-third, when compared to the BiCG method, therefore the algorithm is fast.
基金This researchis supported by Research Fund for Doctoral Programs of Higher Education (Grant No.20030141006) ,and a Program for Changjiang Scholars and Innovative Research Teams in Universities (Grant No.IRT0420)
文摘A higher order boundary dement method (HOBEM) is implemented for wave-current action on structures. The freeterm coefficient and Cauchy principal value ( GPV) integrals are computed by direct methods. Numerical experiments are carried out to validate the computation of free-term coefficient and GPV integrals. The results show that the computation precision of free-term coefficient is very high for various bodies, even with edges and corners, and the convergence speed is fast for CPV integrals for different meshes. The comparison of the second order mean drift force due to wave-current action on a uniform cylinder is made with an analytic solution. It is found that good agreement exists between the present calculation and the analytic solutions. Finally, the numerical code is applied for computing wave-current action on Snorrc TLP.
基金The National Natural Science Foundation of China (No.50308009)
文摘In order to investigate the viscoelastic performance of asphalt mastics, a micro-mechanical model for asphalt mastics was built by applying Burgers model to discrete element simulation and constructing Burgers contact model. Then the numerical simulation of creep tests was conducted, and results from the simulation were compared with the analytical solution for Burgers model. The comparision showed that the two results agreed well with each other, suggesting that discrete element model based on Burgers model could be employed in the numerical simulation for asphalt mastics.
文摘Alzheimer’s disease is a severe neuron disease that damages brain cells which leads to permanent loss of memory also called dementia.Many people die due to this disease every year because this is not curable but early detection of this disease can help restrain the spread.Alzheimer’s ismost common in elderly people in the age bracket of 65 and above.An automated system is required for early detection of disease that can detect and classify the disease into multiple Alzheimer classes.Deep learning and machine learning techniques are used to solvemanymedical problems like this.The proposed system Alzheimer Disease detection utilizes transfer learning on Multi-class classification using brain Medical resonance imagining(MRI)working to classify the images in four stages,Mild demented(MD),Moderate demented(MOD),Non-demented(ND),Very mild demented(VMD).Simulation results have shown that the proposed systemmodel gives 91.70%accuracy.It also observed that the proposed system gives more accurate results as compared to previous approaches.
基金Sponsored by the National Science and Technology Major Project(Grant No.2014ZX04001011)
文摘Residual stress is one of the factors affecting the machining deformation of monolithic structure parts in the aviation industry. Thus, the studies on machining deformation rules induced by residual stresses largely depend on correctly and efficiently measuring the residual stresses of workpieccs. A modified layer-removal method is proposed to measure residual stress by analysing the characteristics of a traditional, layer-removal method. The coefficients of strain release are then deduced according to the simulation results using the finite element method (FEM). Moreover, the residual stress in a 7075T651 aluminium alloy plate is measured using the proposed method, and the results are then analyzed and compared with the data obtained by the traditional methods. The analysis indicates that the modified layer-removal method is effective and practical for measuring the residual stress distribution in pre-stretched aluminium alloy plates.
文摘Quality of life (QOL) is an important topic in social and medical sciences, it has a multidimensional nature and is influenced by many factors. Aim of the Work: In this study we want to assess the impact of cognitive impairment on the health related quality of life (HR-QOL) of community dwelling non demented elderly. Subject and Method: 115 non demented elderly, 60 years and older recruited from outpatient geriatric clinic at Al Mansoura General Hospital, Dakahlia, Egypt. Each participant underwent, comprehensive geriatric assessment, assessing cognitive function using the mini-mental state examination (MMSE) and montreal cognitive function test, assessing the health related quality of life (HR-QOL) by the RAND-36 health survey. Results: We found that the elderly with impaired cognition by both MMSE and Montreal test were significantly older;the ones with lower education, with more depressive symptoms, had more functional impairment and had lower HR-QOL scores than the elderly with normal cognitive function, after controlling for confounders still cognition was a determinant of HR-QOL. Also by linear correlation coefficient a significant correlation between HR-QOL and age, function, cognition and depression was found. Conclusion: Cognition affects significantly HR-QOL of the elderly, so we can say that interventions targeting cognition in the elderly can significantly improve their QOL.
基金Supported by National Natural Science Foundation under Grant No.10202016
文摘In this paper, material properties, geometry parameters and applied loads are assumed to be stochastic, sensitivity computation of structural vibration is presented. The vibration equation of a system is transformed to a static problem by using the Newmark method, and the Taylor expansion stochastic finite element method (TSFEM) is extended for the structural vibration analysis. An example is given, and the calculation results show the validity of the proposed method.