Several preconditioners are proposed for improving the convergence rate of the iterative method derived from splitting. In this paper, the comparison theorem of preconditioned iterative method for regular splitting is...Several preconditioners are proposed for improving the convergence rate of the iterative method derived from splitting. In this paper, the comparison theorem of preconditioned iterative method for regular splitting is proved. And the convergence and comparison theorem for any preconditioner are indicated. This comparison theorem indicates the possibility of finding new preconditioner and splitting. The purpose of this paper is to show that the preconditioned iterative method yields a new splitting satisfying the regular or weak regular splitting. And new combination preconditioners are proposed. In order to denote the validity of the comparison theorem, some numerical examples are shown.展开更多
In this paper, we present m time secant like multi projection algorithm for sparse unconstrained minimization problem. We prove this method are all q superlinearly convergent to the solution about m≥1 . At last, we f...In this paper, we present m time secant like multi projection algorithm for sparse unconstrained minimization problem. We prove this method are all q superlinearly convergent to the solution about m≥1 . At last, we from some numerical results, discuss how to choose the number m to determine the approximating matrix properly in practical use.展开更多
In the designing of the flexible fender pile, M-method is usually adopted. But M-method is usable only in the case that the value of the force (moment M and shear force Q) exerted on the pile above the soil is known. ...In the designing of the flexible fender pile, M-method is usually adopted. But M-method is usable only in the case that the value of the force (moment M and shear force Q) exerted on the pile above the soil is known. In practical cases, only the percussive energy of the ship can be found, while the exact value of the percussive force cannot be computed directly. In this paper, a method is introduced which can be used to calculate the inner force of flexible fender piles by a computer in these cases. First, according to the known docking dynamic energy of a ship, the absorbed energy can be found from the deformation of the pile and the rubber fender respectively, at the same time the value of the force acting on the fender piles and the reaction of fenders can be calculated. Then the inner force and displacement of the fender piles can also be calculated further by M-method. The whole computing process is realized by a computer program and the results obtained are reasonable. In this paper, the computation, the iteration method and the computer program are all expounded in detail. This method can be applied to the design of fender piles and type selection of rubber fenders in practical projects.展开更多
The europium ions doped MMoO4 （M=Sr, Ba） nanophosphors were successfully synthesized via a facile hydrothermal method using isopropanol. The relationship between phosphor crystalline phase, morphology, photohtminesc...The europium ions doped MMoO4 （M=Sr, Ba） nanophosphors were successfully synthesized via a facile hydrothermal method using isopropanol. The relationship between phosphor crystalline phase, morphology, photohtminescent properties and hexadecyl trimethyl ammonium bromide （CTAB） concentration, pH value in precursor solution was investigated. The results indi- cated that the morphology and photoluminescent properties were strongly influenced by CTAB concentration and pH value in precursor solution. In SrMoO4：Eu3＋ hosts, the phosphor surface tended to become smoother as the concentration of CTAB was increased; while particles tended to agglomerate as increasing pH value. The relative intensity ratio of charge transfer band to Eu3＋ characteristic emission peaks of MMoO4：Eu3＋ （M=Sr, Ba） was changed as CTAB concentration and pH value changed. The emission spectra of MMoO4：Eu3＋ （M=Sr, Ba） could be adjusted by CTAB concentration and pH value due to their impacts on the structure. It was im- portant that the different morphologies and photoluminescent properties of MMoO4：Eu3＋ （M=Sr, Ba） could be obtained by the facile hydrothermal method and modulated by changing CTAB concentration and pH value.展开更多
In this paper, a modified Newton type iterative method is considered for ap- proximately solving ill-posed nonlinear operator equations involving m-accretive mappings in Banach space. Convergence rate of the method is...In this paper, a modified Newton type iterative method is considered for ap- proximately solving ill-posed nonlinear operator equations involving m-accretive mappings in Banach space. Convergence rate of the method is obtained based on an a priori choice of the regularization parameter. Our analysis is not based on the sequential continuity of the normalized duality mapping.展开更多
This paper deals with nonlinear second-order initial value problems with time-variable delay.For solving this kind of problems,a class of implicit Runge-Kutta-Nystr¨om(IRKN)methods with Lagrange interpolation are...This paper deals with nonlinear second-order initial value problems with time-variable delay.For solving this kind of problems,a class of implicit Runge-Kutta-Nystr¨om(IRKN)methods with Lagrange interpolation are suggested.Under the suitable condition,it is proved that an IRKN method is globally stable and has the computational accuracy O(h^(min{p,μ+v+1})),where p is the consistency order of the method and μ,n≥0 are the interpolation parameters.Combining a fourth-order compact difference scheme with IRKN methods,an initial-boundary value problem of nonlinear delay wave equations is solved.The presented experiments further confirm the computational effectiveness of the methods and the theoretical results derived in previous.展开更多
The generalized product bi-conjugate gradient(GPBiCG(m,l))method has been recently proposed as a hybrid variant of the GPBi CG and the Bi CGSTAB methods to solve the linear system Ax=b with non-symmetric coefficient m...The generalized product bi-conjugate gradient(GPBiCG(m,l))method has been recently proposed as a hybrid variant of the GPBi CG and the Bi CGSTAB methods to solve the linear system Ax=b with non-symmetric coefficient matrix,and its attractive convergence behavior has been authenticated in many numerical experiments.By means of the Kronecker product and the vectorization operator,this paper aims to develop the GPBi CG(m,l)method to solve the general matrix equation■ and the general discrete-time periodic matrix equations■ which include the well-known Lyapunov,Stein,and Sylvester matrix equations that arise in a wide variety of applications in engineering,communications and scientific computations.The accuracy and efficiency of the extended GPBi CG(m,l)method assessed against some existing iterative methods are illustrated by several numerical experiments.展开更多
This paper praidrs a theurvtheal hasts for establishing the congergente of paraled interative and itratiee techaigues,for computing nmtrfied solution of Ar three A is a singal M-matrix,These results do not assuine A t...This paper praidrs a theurvtheal hasts for establishing the congergente of paraled interative and itratiee techaigues,for computing nmtrfied solution of Ar three A is a singal M-matrix,These results do not assuine A to irreducihle,A concrete relaxed parallet multixpla ting algorithin culled the parallel multispliting AOR algarithm is showed Findly,numericales amples are givep,arhleh show effertielve of parallel iterurise methods for singalar展开更多
Tensor complementarity problem (TCP) is a special kind of nonlinear complementarity problem (NCP). In this paper, we introduce a new class of structure tensor and give some examples. By transforming the TCP to the sys...Tensor complementarity problem (TCP) is a special kind of nonlinear complementarity problem (NCP). In this paper, we introduce a new class of structure tensor and give some examples. By transforming the TCP to the system of nonsmooth equations, we develop a semismooth Newton method for the tensor complementarity problem. We prove the monotone convergence theorem for the proposed method under proper conditions.展开更多
OBJECTIVE To evaluate the safety and effectiveness of robot-assisted percutaneous coronary intervention(R-PCI)compared to traditional manual percutaneous coronary intervention(M-PCI).METHODS This prospective,multicent...OBJECTIVE To evaluate the safety and effectiveness of robot-assisted percutaneous coronary intervention(R-PCI)compared to traditional manual percutaneous coronary intervention(M-PCI).METHODS This prospective,multicenter,randomized controlled,non-inferior clinical trial enrolled patients with coronary heart disease who met the inclusion criteria and had indications for elective percutaneous coronary intervention.Participants were randomly assigned to either the R-PCI group or the M-PCI group.Primary endpoints were clinical and technical success rates.Clinical success was defined as visually estimated residual post-percutaneous coronary intervention stenosis<30% with no 30-day major adverse cardiac events.Technical success in the R-PCI group was defined as successful completion of percutaneous coronary intervention using the ETcath200 robot-assisted system,without conversion to M-PCI in the event of a guidewire or balloon/stent catheter that was unable to cross the vessel or was poorly supported by the catheter.Secondary endpoints included total procedure time,percutaneous coronary intervention procedure time,fluoroscopy time,contrast volume,operator radiation exposure,air kerma,and dose-area product.RESULTS The trial enrolled 152 patients(R-PCI:73 patients,M-PCI:79 patients).Lesions were predominantly B2/C type(73.6%).Both groups achieved 100% clinical success rate.No major adverse cardiac events occurred during the 30-day follow-up.The R-PCI group had a technical success rate of 100%.The R-PCI group had longer total procedure and fluoroscopy times,but lower operator radiation exposure.The percutaneous coronary intervention procedure time,contrast volume,air kerma,and dose-area product were similar between the two groups.CONCLUSIONS For certain complex lesions,performing percutaneous coronary intervention using the ETcath200 robot-assisted system is safe and effective and does not result in conversion to M-PCI.展开更多
In this paper, we discuss the relationship between the sparse symmetric Broyden (SPSB) method [1, 2] and m-time secant-like multi-projection (SMP) method [3] and prove that when m goes to infinity, the SMP method is c...In this paper, we discuss the relationship between the sparse symmetric Broyden (SPSB) method [1, 2] and m-time secant-like multi-projection (SMP) method [3] and prove that when m goes to infinity, the SMP method is corresponding to the SPSB method.展开更多
文摘Several preconditioners are proposed for improving the convergence rate of the iterative method derived from splitting. In this paper, the comparison theorem of preconditioned iterative method for regular splitting is proved. And the convergence and comparison theorem for any preconditioner are indicated. This comparison theorem indicates the possibility of finding new preconditioner and splitting. The purpose of this paper is to show that the preconditioned iterative method yields a new splitting satisfying the regular or weak regular splitting. And new combination preconditioners are proposed. In order to denote the validity of the comparison theorem, some numerical examples are shown.
文摘In this paper, we present m time secant like multi projection algorithm for sparse unconstrained minimization problem. We prove this method are all q superlinearly convergent to the solution about m≥1 . At last, we from some numerical results, discuss how to choose the number m to determine the approximating matrix properly in practical use.
文摘In the designing of the flexible fender pile, M-method is usually adopted. But M-method is usable only in the case that the value of the force (moment M and shear force Q) exerted on the pile above the soil is known. In practical cases, only the percussive energy of the ship can be found, while the exact value of the percussive force cannot be computed directly. In this paper, a method is introduced which can be used to calculate the inner force of flexible fender piles by a computer in these cases. First, according to the known docking dynamic energy of a ship, the absorbed energy can be found from the deformation of the pile and the rubber fender respectively, at the same time the value of the force acting on the fender piles and the reaction of fenders can be calculated. Then the inner force and displacement of the fender piles can also be calculated further by M-method. The whole computing process is realized by a computer program and the results obtained are reasonable. In this paper, the computation, the iteration method and the computer program are all expounded in detail. This method can be applied to the design of fender piles and type selection of rubber fenders in practical projects.
基金Project supported by the Nation Natural Science Foundation of China(51562025)Graduate Student Innovation Special Funds(YC2016-S085)
文摘The europium ions doped MMoO4 （M=Sr, Ba） nanophosphors were successfully synthesized via a facile hydrothermal method using isopropanol. The relationship between phosphor crystalline phase, morphology, photohtminescent properties and hexadecyl trimethyl ammonium bromide （CTAB） concentration, pH value in precursor solution was investigated. The results indi- cated that the morphology and photoluminescent properties were strongly influenced by CTAB concentration and pH value in precursor solution. In SrMoO4：Eu3＋ hosts, the phosphor surface tended to become smoother as the concentration of CTAB was increased; while particles tended to agglomerate as increasing pH value. The relative intensity ratio of charge transfer band to Eu3＋ characteristic emission peaks of MMoO4：Eu3＋ （M=Sr, Ba） was changed as CTAB concentration and pH value changed. The emission spectra of MMoO4：Eu3＋ （M=Sr, Ba） could be adjusted by CTAB concentration and pH value due to their impacts on the structure. It was im- portant that the different morphologies and photoluminescent properties of MMoO4：Eu3＋ （M=Sr, Ba） could be obtained by the facile hydrothermal method and modulated by changing CTAB concentration and pH value.
文摘In this paper, a modified Newton type iterative method is considered for ap- proximately solving ill-posed nonlinear operator equations involving m-accretive mappings in Banach space. Convergence rate of the method is obtained based on an a priori choice of the regularization parameter. Our analysis is not based on the sequential continuity of the normalized duality mapping.
文摘This paper deals with nonlinear second-order initial value problems with time-variable delay.For solving this kind of problems,a class of implicit Runge-Kutta-Nystr¨om(IRKN)methods with Lagrange interpolation are suggested.Under the suitable condition,it is proved that an IRKN method is globally stable and has the computational accuracy O(h^(min{p,μ+v+1})),where p is the consistency order of the method and μ,n≥0 are the interpolation parameters.Combining a fourth-order compact difference scheme with IRKN methods,an initial-boundary value problem of nonlinear delay wave equations is solved.The presented experiments further confirm the computational effectiveness of the methods and the theoretical results derived in previous.
基金Supported by the National Natural Sciences Foundation of China(Grant Nos.11501079 11571061)Part by the Higher Education Commission of Egypt
文摘The generalized product bi-conjugate gradient(GPBiCG(m,l))method has been recently proposed as a hybrid variant of the GPBi CG and the Bi CGSTAB methods to solve the linear system Ax=b with non-symmetric coefficient matrix,and its attractive convergence behavior has been authenticated in many numerical experiments.By means of the Kronecker product and the vectorization operator,this paper aims to develop the GPBi CG(m,l)method to solve the general matrix equation■ and the general discrete-time periodic matrix equations■ which include the well-known Lyapunov,Stein,and Sylvester matrix equations that arise in a wide variety of applications in engineering,communications and scientific computations.The accuracy and efficiency of the extended GPBi CG(m,l)method assessed against some existing iterative methods are illustrated by several numerical experiments.
文摘This paper praidrs a theurvtheal hasts for establishing the congergente of paraled interative and itratiee techaigues,for computing nmtrfied solution of Ar three A is a singal M-matrix,These results do not assuine A to irreducihle,A concrete relaxed parallet multixpla ting algorithin culled the parallel multispliting AOR algarithm is showed Findly,numericales amples are givep,arhleh show effertielve of parallel iterurise methods for singalar
文摘Tensor complementarity problem (TCP) is a special kind of nonlinear complementarity problem (NCP). In this paper, we introduce a new class of structure tensor and give some examples. By transforming the TCP to the system of nonsmooth equations, we develop a semismooth Newton method for the tensor complementarity problem. We prove the monotone convergence theorem for the proposed method under proper conditions.
基金supported by the National Key Research and Development Program of China(No.2022YFC3602500)Beijing High-level Public Health Technical Talents Construction Project(Discipline Leader-03-24)Beijing Hospitals Authority’s Ascent Plan(DFL20240601).
文摘OBJECTIVE To evaluate the safety and effectiveness of robot-assisted percutaneous coronary intervention(R-PCI)compared to traditional manual percutaneous coronary intervention(M-PCI).METHODS This prospective,multicenter,randomized controlled,non-inferior clinical trial enrolled patients with coronary heart disease who met the inclusion criteria and had indications for elective percutaneous coronary intervention.Participants were randomly assigned to either the R-PCI group or the M-PCI group.Primary endpoints were clinical and technical success rates.Clinical success was defined as visually estimated residual post-percutaneous coronary intervention stenosis<30% with no 30-day major adverse cardiac events.Technical success in the R-PCI group was defined as successful completion of percutaneous coronary intervention using the ETcath200 robot-assisted system,without conversion to M-PCI in the event of a guidewire or balloon/stent catheter that was unable to cross the vessel or was poorly supported by the catheter.Secondary endpoints included total procedure time,percutaneous coronary intervention procedure time,fluoroscopy time,contrast volume,operator radiation exposure,air kerma,and dose-area product.RESULTS The trial enrolled 152 patients(R-PCI:73 patients,M-PCI:79 patients).Lesions were predominantly B2/C type(73.6%).Both groups achieved 100% clinical success rate.No major adverse cardiac events occurred during the 30-day follow-up.The R-PCI group had a technical success rate of 100%.The R-PCI group had longer total procedure and fluoroscopy times,but lower operator radiation exposure.The percutaneous coronary intervention procedure time,contrast volume,air kerma,and dose-area product were similar between the two groups.CONCLUSIONS For certain complex lesions,performing percutaneous coronary intervention using the ETcath200 robot-assisted system is safe and effective and does not result in conversion to M-PCI.
文摘In this paper, we discuss the relationship between the sparse symmetric Broyden (SPSB) method [1, 2] and m-time secant-like multi-projection (SMP) method [3] and prove that when m goes to infinity, the SMP method is corresponding to the SPSB method.
