A finite element asymptotic analysis for determining the lower bound dynamic buckling estimates of imperfection-sensitive structures under step load of infinite duration is presented. The lower bound dynamic buckling ...A finite element asymptotic analysis for determining the lower bound dynamic buckling estimates of imperfection-sensitive structures under step load of infinite duration is presented. The lower bound dynamic buckling loads and the corresponding displacements are sought in the form of asymptotic expansions based on the static stability criterion and they can be determined by solving numerically (FEM) several linear problems with a single nonsingular sub-stiffness matrix.展开更多
For the principal eigenvalue with bilateral Dirichlet boundary condition, the so-called basic estimates were originally obtained by capacitary method. The Neumann case (i.e., the ergodic case) is even harder, and wa...For the principal eigenvalue with bilateral Dirichlet boundary condition, the so-called basic estimates were originally obtained by capacitary method. The Neumann case (i.e., the ergodic case) is even harder, and was deduced from the Dirichlet one plus a use of duality and the coupling method. In this paper, an alternative and more direct proof for the basic estimates is presented. The estimates in the Dirichlet case are then improved by a typical application of a recent variational formula. As a dual of the Dirichlet case, the refine problem for bilateral Neumann boundary condition is also treated. The paper starts with the continuous case (one-dimensional diffusions) and ends at the discrete one (birth-death processes). Possible generalization of the results studied here is discussed at the end of the paper展开更多
Background Reactive oxygen species are thought to contribute to the development of renal damage. The P22phox subunit of nicotinamide adenine dinucleotide phosphate (NAPDH) oxidase, encoded by the cytochrome b245a po...Background Reactive oxygen species are thought to contribute to the development of renal damage. The P22phox subunit of nicotinamide adenine dinucleotide phosphate (NAPDH) oxidase, encoded by the cytochrome b245a polypeptide gene, CYBA, plays a key role in superoxide anion production. We investigated the association of CYBA rs7195830 polymorphism with estimated glomerular filtration rate (eGFR) and the role it plays in the pathogenesis of chronic kidney disease (CKD) in a Han Chinese sample. Methods The Gaoyou study enrolled 4473 participants. Serum levels of creatinine were measured and eGFR was estimated using the Chronic Kidney Disease Epidemiology Collaboration equations. The CYBA polymorphisms were genotyped. Then we investigated the association between eGFR and the rs7195830 polymorphism in the recessive model. Results The AA genotype of rs7195830 was associated with significantly lower values of eGFR compared with the GG and AG genotypes ((102.76±17.07) ml.min-1.1.73 m-2 vs. (105.08±16.30) ml'min-1.1.73 m-2). The association remained significant in the recessive model after adjusting for age, gender, body mass index, smoking, hypertension, diabetes mellitus, uric acid, triglyceride, low density lipoprotein cholesterol and high density lipoprotein cholesterol (β=1.666, P=0.031). The rs7195832 AA genotype was an independent risk factor for CKD: eGFR 〈60 ml.min-1.1.73 m-2 (odds ratio=3.32; 95% CI= 1.21-9.13). Conclusion The AA genotype of rs7195830 is independently associated with lower estimated glomerular filtration rate and is significantly associated with CKD.展开更多
This work investigates a simple and practical bio-immune optimization approach to solve a kind of chance-constrained programming problem without known noisy attributes, after probing into a lower bound estimate of sam...This work investigates a simple and practical bio-immune optimization approach to solve a kind of chance-constrained programming problem without known noisy attributes, after probing into a lower bound estimate of sample size for any random variable. Such approach mainly consists of sample allocation, evaluation, proliferation and mutation. The former two, depending on a lower bound estimate acquired, not only decide the sample size of random variable and the importance level of each evolving B cell, but also ensure that such B cell is evaluated with low computational cost; the third makes diverse B cells participate in evolution and suppresses the influence of noise; the last, which associates with the information on population diversity and fitness inheritance, creates diverse and high-affinity B cells. Under such approach, three similar immune algorithms are derived after selecting different mutation rules. The experiments, by comparison against two valuable genetic algorithms, have illustrated that these immune algorithms are competitive optimizers capable of effectively executing noisy compensation and searching for the desired optimal reliable solution.展开更多
In high-level synthesis of VLSI circuits, good lower bound prediction canefficiently narrow down the large space of possible designs. Previous approaches predict the lowerbound by relaxing or even ignoring the precede...In high-level synthesis of VLSI circuits, good lower bound prediction canefficiently narrow down the large space of possible designs. Previous approaches predict the lowerbound by relaxing or even ignoring the precedence constraints of the data flow graph (DFG), andresult in inaccuracy of the lower bound. The loop folding and conditional branch were also notconsidered. In this paper, a new stepwise refinement algorithm is proposed, which takesconsideration of precedence constraints of the DFG to estimate the lower bound of hardware resourcesunder time constraints. Processing techniques to handle multi-cycle, chaining, pipelining, as wellas loop folding and mutual exclusion among conditional branches are also incorporated in thealgorithm. Experimental results show that the algorithm can produce a very tight and close tooptimal lower bound in reasonable computation time.展开更多
We present the convergence analysis of the rectangular Morley element scheme utilised on the second order problem in arbitrary dimensions. Specifically, we prove that the convergence of the scheme is of (D(h) order...We present the convergence analysis of the rectangular Morley element scheme utilised on the second order problem in arbitrary dimensions. Specifically, we prove that the convergence of the scheme is of (D(h) order in energy norm and of O(h2) order in L2 norm on general d-rectangular triangulations. Moreover, when the triangulation is uniform, the convergence rate can be of O(h2) order in energy norm, and the convergence rate in L2 norm is still of O(h2) order, which cannot be improved. Numerical examples are presented to demonstrate our theoretical results.展开更多
基金The project supported by the State Education Commission of China
文摘A finite element asymptotic analysis for determining the lower bound dynamic buckling estimates of imperfection-sensitive structures under step load of infinite duration is presented. The lower bound dynamic buckling loads and the corresponding displacements are sought in the form of asymptotic expansions based on the static stability criterion and they can be determined by solving numerically (FEM) several linear problems with a single nonsingular sub-stiffness matrix.
基金This work was supported in part by the National Natural Science Foundation of China (Grant No. 11131003) and the "985" Project from the Ministry of Education in China.
文摘For the principal eigenvalue with bilateral Dirichlet boundary condition, the so-called basic estimates were originally obtained by capacitary method. The Neumann case (i.e., the ergodic case) is even harder, and was deduced from the Dirichlet one plus a use of duality and the coupling method. In this paper, an alternative and more direct proof for the basic estimates is presented. The estimates in the Dirichlet case are then improved by a typical application of a recent variational formula. As a dual of the Dirichlet case, the refine problem for bilateral Neumann boundary condition is also treated. The paper starts with the continuous case (one-dimensional diffusions) and ends at the discrete one (birth-death processes). Possible generalization of the results studied here is discussed at the end of the paper
文摘Background Reactive oxygen species are thought to contribute to the development of renal damage. The P22phox subunit of nicotinamide adenine dinucleotide phosphate (NAPDH) oxidase, encoded by the cytochrome b245a polypeptide gene, CYBA, plays a key role in superoxide anion production. We investigated the association of CYBA rs7195830 polymorphism with estimated glomerular filtration rate (eGFR) and the role it plays in the pathogenesis of chronic kidney disease (CKD) in a Han Chinese sample. Methods The Gaoyou study enrolled 4473 participants. Serum levels of creatinine were measured and eGFR was estimated using the Chronic Kidney Disease Epidemiology Collaboration equations. The CYBA polymorphisms were genotyped. Then we investigated the association between eGFR and the rs7195830 polymorphism in the recessive model. Results The AA genotype of rs7195830 was associated with significantly lower values of eGFR compared with the GG and AG genotypes ((102.76±17.07) ml.min-1.1.73 m-2 vs. (105.08±16.30) ml'min-1.1.73 m-2). The association remained significant in the recessive model after adjusting for age, gender, body mass index, smoking, hypertension, diabetes mellitus, uric acid, triglyceride, low density lipoprotein cholesterol and high density lipoprotein cholesterol (β=1.666, P=0.031). The rs7195832 AA genotype was an independent risk factor for CKD: eGFR 〈60 ml.min-1.1.73 m-2 (odds ratio=3.32; 95% CI= 1.21-9.13). Conclusion The AA genotype of rs7195830 is independently associated with lower estimated glomerular filtration rate and is significantly associated with CKD.
基金supported in part by National Natural Science Foundation of China(Nos.61563009 and 61065010)Doctoral Fund of Ministry of Education of China(No.20125201110003)
文摘This work investigates a simple and practical bio-immune optimization approach to solve a kind of chance-constrained programming problem without known noisy attributes, after probing into a lower bound estimate of sample size for any random variable. Such approach mainly consists of sample allocation, evaluation, proliferation and mutation. The former two, depending on a lower bound estimate acquired, not only decide the sample size of random variable and the importance level of each evolving B cell, but also ensure that such B cell is evaluated with low computational cost; the third makes diverse B cells participate in evolution and suppresses the influence of noise; the last, which associates with the information on population diversity and fitness inheritance, creates diverse and high-affinity B cells. Under such approach, three similar immune algorithms are derived after selecting different mutation rules. The experiments, by comparison against two valuable genetic algorithms, have illustrated that these immune algorithms are competitive optimizers capable of effectively executing noisy compensation and searching for the desired optimal reliable solution.
文摘In high-level synthesis of VLSI circuits, good lower bound prediction canefficiently narrow down the large space of possible designs. Previous approaches predict the lowerbound by relaxing or even ignoring the precedence constraints of the data flow graph (DFG), andresult in inaccuracy of the lower bound. The loop folding and conditional branch were also notconsidered. In this paper, a new stepwise refinement algorithm is proposed, which takesconsideration of precedence constraints of the DFG to estimate the lower bound of hardware resourcesunder time constraints. Processing techniques to handle multi-cycle, chaining, pipelining, as wellas loop folding and mutual exclusion among conditional branches are also incorporated in thealgorithm. Experimental results show that the algorithm can produce a very tight and close tooptimal lower bound in reasonable computation time.
基金supported by National Natural Science Foundation of China (Grant Nos. 11471026, 11271035, 91430213, 11421101 and 11101415)
文摘We present the convergence analysis of the rectangular Morley element scheme utilised on the second order problem in arbitrary dimensions. Specifically, we prove that the convergence of the scheme is of (D(h) order in energy norm and of O(h2) order in L2 norm on general d-rectangular triangulations. Moreover, when the triangulation is uniform, the convergence rate can be of O(h2) order in energy norm, and the convergence rate in L2 norm is still of O(h2) order, which cannot be improved. Numerical examples are presented to demonstrate our theoretical results.