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Commutators of Weighted Lipschitz Functions and Multilinear Singular Integrals with Non-Smooth Kernels 被引量:3
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作者 LIAN Jia-li MA Bo-lin WU Huo-xiong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第3期353-367,共15页
This paper is devoted to studying the commutators of the multilinear singular integral operators with the non-smooth kernels and the weighted Lipschitz functions. Some mapping properties for two types of commutators o... This paper is devoted to studying the commutators of the multilinear singular integral operators with the non-smooth kernels and the weighted Lipschitz functions. Some mapping properties for two types of commutators on the weighted Lebesgue spaces, which extend and generalize some previous results, are obtained. 展开更多
关键词 COMMUTATOR multilinear singular integral non-smooth kernel weighted Lipschitz function weights.
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High accuracy non-equidistant method for singular perturbation reaction-diffusion problem 被引量:5
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作者 蔡新 蔡丹琳 +1 位作者 吴瑞潜 谢康和 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第2期175-182,共8页
Singular perturbation reaction-diffusion problem with Dirichlet boundary condition is considered. It is a multi-scale problem. Presence of small parameter leads to boundary layer phenomena in both sides of the region.... Singular perturbation reaction-diffusion problem with Dirichlet boundary condition is considered. It is a multi-scale problem. Presence of small parameter leads to boundary layer phenomena in both sides of the region. A non-equidistant finite difference method is presented according to the property of boundary layer. The region is divided into an inner boundary layer region and an outer boundary layer region according to transition point of Shishkin. The steps sizes are equidistant in the outer boundary layer region. The step sizes are gradually increased in the inner boundary layer region such that half of the step sizes are different from each other. Truncation error is estimated. The proposed method is stable and uniformly convergent with the order higher than 2. Numerical results are given, which are in agreement with the theoretical result. 展开更多
关键词 singular perturbation REACTION-DIFFUSION uniform convergence high accuracy non-equidistant
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A CHARACTERIZATION OF SCHECHTER'S ESSENTIAL SPECTRUM BY MEAN OF MEASURE OF NON-STRICT-SINGULARITY AND APPLICATION TO MATRIX OPERATOR 被引量:1
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作者 Nedra Moalla 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2329-2340,共12页
In this paper we use the notion of measure of non-strict-singularity to give some results on Fredholm operators and we establish a fine description of the Schechter essential spectrum of a closed densely defined linea... In this paper we use the notion of measure of non-strict-singularity to give some results on Fredholm operators and we establish a fine description of the Schechter essential spectrum of a closed densely defined linear operator. 展开更多
关键词 measure of non-strict-singularity Fredholm operator Schechter essentialspectrum matrix operator
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Recursive State-space Model Identification of Non-uniformly Sampled Systems Using Singular Value Decomposition 被引量:2
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作者 王宏伟 刘涛 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第Z1期1268-1273,共6页
In this paper a recursive state-space model identification method is proposed for non-uniformly sampled systems in industrial applications. Two cases for measuring all states and only output(s) of such a system are co... In this paper a recursive state-space model identification method is proposed for non-uniformly sampled systems in industrial applications. Two cases for measuring all states and only output(s) of such a system are considered for identification. In the case of state measurement, an identification algorithm based on the singular value decomposition(SVD) is developed to estimate the model parameter matrices by using the least-squares fitting. In the case of output measurement only, another identification algorithm is given by combining the SVD approach with a hierarchical identification strategy. An example is used to demonstrate the effectiveness of the proposed identification method. 展开更多
关键词 non-uniformly sampling system STATE-SPACE model IDENTIFICATION singular value decomposition RECURSIVE algorithm
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Upper bound for the time derivative of entropy for a stochastic dynamical system with double singularities driven by non-Gaussian noise 被引量:2
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作者 郭培荣 徐伟 刘迪 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第3期233-238,共6页
A stochastic dynamical system with double singularities driven by non-Gaussian noise is investigated. The Fokker Plank equation of the system is obtained through the path-integral approach and the method of transforma... A stochastic dynamical system with double singularities driven by non-Gaussian noise is investigated. The Fokker Plank equation of the system is obtained through the path-integral approach and the method of transformation. Based on the definition of Shannon's information entropy and the Schwartz inequality principle, the upper bound for the time derivative of entropy is calculated both in the absence and in the presence of non-equilibrium constraint. The present calculations can be used to interpret the effects of the system dissipative parameter, the system singularity strength parameter, the noise correlation time and the noise deviation parameter on the upper bound. 展开更多
关键词 non-Gaussian noise stochastic dynamical system with double singularities informationentropy upper bound for the time derivative of entropy
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On non-singular GRADELA crack fields
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作者 Elias C.Aifantis 《Theoretical & Applied Mechanics Letters》 CAS 2014年第5期30-36,共7页
A brief account is provided on crack-tip solutions that have recently been published in the literature by employing the so-called GRADELA model and its variants. The GRADELA model is a simple gradient elasticity theor... A brief account is provided on crack-tip solutions that have recently been published in the literature by employing the so-called GRADELA model and its variants. The GRADELA model is a simple gradient elasticity theory involving one internal length in addition to the two Lame' constants, in an effort to eliminate elastic singularities and discontinuities and to interpret elastic size effects. The non-singular strains and non-singular (but sometimes singular or even hypersingular) stresses derived this way under different boundary conditions differ from each other and their physical meaning in not clear. This is discussed which focus on the form and physical meaning of non-singular solutions for crack-tip stresses and strains that are possible to obtain within the GRADELA model and its extensions. 展开更多
关键词 gradient elasticity non-singular cracks FRACTURE
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Non-Singular Trees, Unicyclic Graphs and Bicyclic Graphs
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作者 Haicheng Ma Danyang Li Chengling Xie 《Applied Mathematics》 2020年第1期1-7,共7页
We called graph G non-singular if adjacency matrix A (G) of G is non-singular. A connected graph with n vertices and n-1, n and n+1 edges are called the tree, the unicyclic graph and the bicyclic graph. Respectively, ... We called graph G non-singular if adjacency matrix A (G) of G is non-singular. A connected graph with n vertices and n-1, n and n+1 edges are called the tree, the unicyclic graph and the bicyclic graph. Respectively, as we all know, each connected bicyclic graph must contain ∞(a,s,b) or?θ(p,l,q) as the induced subgraph. In this paper, by using three graph transformations which do not change the singularity of the graph, the non-singular trees, unicyclic graphs and bicyclic graphs are obtained. 展开更多
关键词 ADJACENCY MATRIX non-singular RANK NULLITY
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Existence and Non-Existence Result for Singular Quasilinear Elliptic Equations
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作者 Mingzhu Wu Zuodong Yang 《Applied Mathematics》 2010年第5期351-356,共6页
We prove the existence of a ground state solution for the qusilinear elliptic equation in , under suitable conditions on a locally Holder continuous non-linearity , the non-linearity may exhibit a singularity as . We ... We prove the existence of a ground state solution for the qusilinear elliptic equation in , under suitable conditions on a locally Holder continuous non-linearity , the non-linearity may exhibit a singularity as . We also prove the non-existence of radially symmetric solutions to the singular elliptic equation in , as where . 展开更多
关键词 QUASILINEAR ELLIPTIC EQUATIONS EXISTENCE non-EXISTENCE singular
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Unified symmetry of non-holonomic singular systems
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作者 李元成 王静 +2 位作者 夏丽莉 后其宝 荆宏星 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第10期2841-2844,共4页
In this paper, the unified symmetry of non-holonomic singular systems is studied. The differential equations of motion of the systems are given. The definition and the criterion of the unified symmetry for the systems... In this paper, the unified symmetry of non-holonomic singular systems is studied. The differential equations of motion of the systems are given. The definition and the criterion of the unified symmetry for the systems are presented. The Noether conserved quantity, the Hojman conserved quantity and the Mei conserved quantity are obtained. An example is given to illustrate the application of the results. 展开更多
关键词 singular system non-holonomic constraint unified symmetry conserved quantity
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Weighted estimates for commutators of singular integral operators with non-smooth kernels
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作者 ZHANG Lin JIANG Yin-sheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第3期318-324,共7页
In this paper, we establish the boundedness of commutators of singular integral operators with non-smooth kernels on weighted Lipschitz spaces Lipβ,ω. The condition on the kernel in this paper is weaker than the usu... In this paper, we establish the boundedness of commutators of singular integral operators with non-smooth kernels on weighted Lipschitz spaces Lipβ,ω. The condition on the kernel in this paper is weaker than the usual pointwise HSrmander condition. 展开更多
关键词 Lipβ ω space COMMUTATOR singular integral operator non-smooth kernel.
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Creation of a Non-Expanding, Non-Singular Universe
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作者 Walter Petry 《Journal of Modern Physics》 2015年第8期1085-1094,共10页
A theory of gravitation in flat space-time is applied to homogeneous, isotropic cosmological models. There are non-singular cosmological models. A natural interpretation is a non-expanding universe. The redshift is an... A theory of gravitation in flat space-time is applied to homogeneous, isotropic cosmological models. There are non-singular cosmological models. A natural interpretation is a non-expanding universe. The redshift is an intrinsic effect and not a Doppler effect. The universe contains only energy in the beginning, i.e. no matter exists. In the course of time matter and radiation are created from energy where the whole energy is conserved. Matter increases with time but a certain time after the beginning of the universe the creation of matter is finished and the universe appears like a static one. A modified Hubble law is considered which may explain the high redshifts of objects in the universe without the assumption of dark energy. 展开更多
关键词 UNIVERSE non-Expanding non-singular CREATION of Matter Conservation of Total Energy Redshift Is NO Doppler Effect Modified Hubble Law
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Boundedness of Multilinear Singular Integrals and Their Commutators on Morrey-Herz Spaces with Non-doubling Measures
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作者 周娟 朱月萍 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第4期545-555,共11页
Let μ be a non-negative Radon measure on R^d which satisfies some growth conditions. The boundedness of multilinear Calderon-Zygmund singular integral operator T and its commutators with RBMO functions on Morrey-Herz... Let μ be a non-negative Radon measure on R^d which satisfies some growth conditions. The boundedness of multilinear Calderon-Zygmund singular integral operator T and its commutators with RBMO functions on Morrey-Herz spaces are obtained if T is bounded from L^1(μ)χ…χ L^1(μ) to L1/m,∞(μ). 展开更多
关键词 non-doubling measure multilinear singular integral operator COMMUTATOR Morrey-Herz space
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On the Differential Formulas for Singular Integrals of High Non-Integral Order
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作者 ZHONG Shou-guo (College of Mathematics and Computer Science,Wuhan University,Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 2000年第1期6-6,共1页
When kernel density is in the class of continuous function to possessing sufficient derivative of high order(and needn't in the class of corresponding Holder function),in this paper it is given the continuity and... When kernel density is in the class of continuous function to possessing sufficient derivative of high order(and needn't in the class of corresponding Holder function),in this paper it is given the continuity and the differential formulas for singular integrals of high non--integral order. The above results themselves and in order to prove in future the formulas to changing order of integration for singular integrals of high non-integral order(another paper) will have important significance. The method to prove in this paper is more different from the method in the corresponding cass of singular integrals of high integral order. 展开更多
关键词 singular integral of high non-integral order CONTINUITY differential formala
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A Proof of the Non-Singularity of the <i>D</i>Matrix Used in Deriving the Two—Step Butcher’s Hybrid Scheme for the Solution of Initial Value Problems
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作者 R. O. Akinola K. J. Ajibade 《Journal of Applied Mathematics and Physics》 2021年第12期3177-3201,共25页
In this paper, we state and prove the conditions for the non-singularity of the <em>D</em> matrix used in deriving the continuous form of the Two-step Butcher’s hybrid scheme and from it the discrete form... In this paper, we state and prove the conditions for the non-singularity of the <em>D</em> matrix used in deriving the continuous form of the Two-step Butcher’s hybrid scheme and from it the discrete forms are deduced. We also show that the discrete scheme gives outstanding results for the solution of stiff and non-stiff initial value problems than the 5<sup>th</sup> order Butcher’s algorithm in predictor-corrector form. 展开更多
关键词 Linear Multistep Methods non-singularity Interpolation and Collocation
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Iterated Commutators for Multilinear Singular Integral Operators on Morrey Space with Non-Doubling Measures
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作者 Tie Li Yinsheng Jiang Yaoming Niu 《Journal of Applied Mathematics and Physics》 2020年第1期53-69,共17页
Let μ be a non-negative Radon measure on Rd which only satisfies the following growth condition that there exists a positive constant C such that μ(B(x,r)) ≤ Crn?for all x∈ Rd, r > 0 and some fixed n ∈ (0,d]. ... Let μ be a non-negative Radon measure on Rd which only satisfies the following growth condition that there exists a positive constant C such that μ(B(x,r)) ≤ Crn?for all x∈ Rd, r > 0 and some fixed n ∈ (0,d]. This paper is interested in the properties of the iterated commutators of multilinear singular integral operators on Morrey spaces?.Precisely speaking, we show that the iterated commutators generated by multilinear singular integrals operators are bounded from to where (Regular Bounded Mean Oscillation space) and 1 qj ≤ pj ∞ with 1/p = 1/p1 + ... + 1/pm and 1/q = 1/q1+ ... + 1/qm. 展开更多
关键词 non-Doubling Measures MORREY Space MULTILINEAR singular Integral Operators RBMO COMMUTATOR
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Limit Treatment of Space-Time Foam Calculations If Non Pathological Big Bang Singularity Is Accessible to Modified Einstein Equations
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作者 Andrew Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第3期438-453,共16页
When initial radius if Stoica actually derived Einstein equations in a formalism which removes the big bang singularity pathology, then the reason for Planck length no longer holds. We follow what Ng derived as limit ... When initial radius if Stoica actually derived Einstein equations in a formalism which removes the big bang singularity pathology, then the reason for Planck length no longer holds. We follow what Ng derived as limit calculations as to a space time length factor Without the drop off of the vacuum energy as given by is at least the value of . We review the work by Ng as to quantum foam as to how that affects a general expression as to energy when , with determined at least approximately by arguments he presented in 2008 in the Dark side of the universe conference. Well before certain effects make themselves apparent, in ways which are illustrated in the manuscript. Having at a point singularity would remove expansion by the scale factor, so that the extreme version of Stoica’s treatment in an isolated 4-dimensional universe would be no expansion at all. 展开更多
关键词 Fjortoft THEOREM Thermodynamic Potential Matter Creation Vacuum Energy Mach’s THEOREM non-Pathological singularITY Affecting Einstein Equations PLANCK Length. BRANE WORLDS
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肥胖儿童non-HDL-C、remnant cholesterol与亚临床动脉粥样硬化的关系 被引量:4
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作者 焦朝艳 刘戈力 +4 位作者 鲍鹏丽 魏莹 杨箐岩 郑荣秀 赵菁 《天津医科大学学报》 2014年第1期25-28,共4页
目的:了解non-HDL-C和remnant cholesterol与肥胖儿童亚临床动脉粥样硬化(AS)的关系。方法:根据甘油三酯(TG)水平将65例肥胖儿童(肥胖组)分为I组(TG≥2.3 mmol/L)32例,II组(TG<2.3 mmol/L)33例,与肥胖组儿童性别年龄相匹配的正常体... 目的:了解non-HDL-C和remnant cholesterol与肥胖儿童亚临床动脉粥样硬化(AS)的关系。方法:根据甘油三酯(TG)水平将65例肥胖儿童(肥胖组)分为I组(TG≥2.3 mmol/L)32例,II组(TG<2.3 mmol/L)33例,与肥胖组儿童性别年龄相匹配的正常体质量儿童30例为III组(对照组)。比较3组儿童血脂指标,对肥胖组各项血脂指标与血浆致动脉粥样硬化指数(AIP)进行相关性分析,肥胖患儿体质指数、血脂指标与颈动脉内径、内膜-中层厚度(c-IMT)、血流参数进行相关性分析。结果:I组、II组的TG、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、non-HDL-C、remnant cholesterol、AIP均较对照组升高,高密度脂蛋白胆固醇(HDL-C)较对照组降低,且I组的remnant cholesterol、AIP均较II组升高。肥胖组儿童AIP与TG、non-HDL-C、remnant cholesterol呈正相关,与HDL-C呈负相关。37例行颈动脉超声检查的肥胖儿童的c-IMT较正常儿童的增厚。结论:non-HDL-C、remnant cholesterol在肥胖儿童亚临床AS中有重要作用,在肥胖儿童血脂异常的治疗中应关注non-HDL-C、remnant cholesterol的变化。 展开更多
关键词 儿童肥胖 亚临床动脉粥样硬化 non—HDL—C REMNANT CHOLESTEROL 血浆致动脉粥样硬化指数 颈动脉内膜-中层厚度
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ON THE HOLOMORPHIC SOLUTION OF NON-LINEAR TOTALLY CHARACTERISTIC EQUATIONS WITH SEVERAL SPACE VARIABLES 被引量:5
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作者 陈化 罗壮初 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期393-403,共11页
In this paper the authors study a class of non-linear singular partial differential equation in complex domain C-t x C-x(n). Under certain assumptions, they prove the existence and uniqueness of holomorphic solution n... In this paper the authors study a class of non-linear singular partial differential equation in complex domain C-t x C-x(n). Under certain assumptions, they prove the existence and uniqueness of holomorphic solution near origin of C-t x C-x(n). 展开更多
关键词 non-LINEAR singular partial differential equation holomorphic solution
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Shenqi Fuzheng injection combined with GP chemotherapy in the treatment of advanced non-small cell lung cancer: a meta-analysis 被引量:13
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作者 Qiang Zhang Yi-Huan Fan +2 位作者 Teng Zhang Xiao-Lan Qin Ji-Fang Song 《TMR Integrative Medicine》 2017年第2期68-78,共11页
Objective: To evaluate the clinical efficacy of Shenqi Fuzheng injection combined with gemcitabine plus cisplatin(GP) in the treatment of advanced non-small cell lung cancer (NSCLC). Methods: we performed a syst... Objective: To evaluate the clinical efficacy of Shenqi Fuzheng injection combined with gemcitabine plus cisplatin(GP) in the treatment of advanced non-small cell lung cancer (NSCLC). Methods: we performed a systematicsearch in the electronic databases such as Cochrane Library, Pubmed, Embase, Chinese Journal Full-text Database,Chinese Biomedical Literature Database, Chinese Science and Technology Periodical Full-text Database andWanfang Database up to 30 January 2017. Randomized controlled trials (RCT) of Shenqi Fuzheng Injectioncombined with GP chemotherapy in the treatment of advanced NSCLC were searched, and all the RCTs wereconducted on methodological quality assessment. Data extraction and data analysis were according to standards ofCochrane systematic review. Results: Eight trials were included including a total of 701 patients. Meta-analysisresults: Shenqi Fuzheng injection combined with GP chemotherapy could significantly improve the functionalstatus of patients with NSCLC (OR = 3.44, 95% CI [2.26, 5.25], P 〈 0.0001) and clinical treatment efficacy (OR =(OR = 0.31, 95%CI [0.20, 0.47], P 〈 0.0001. The rate of leukopenia (OR = .31, 95%CI [0.20,0.47], P 〈 0.0001),thrombocytopenia (OR = 0.58, 95%CI [0.37, 0.91], P = 0.020), hemoglobin decline ((OR = 0.31, 95%CI [0.16,0.59], P = 0.0004) and incidence of gastrointestinal reactions (OR = 0.58,P 〈 0.05) could be reduced. Conclusion:Shenqi Fuzheng injection combined with GP chemotherapy in the treatment of advanced NSCLC obtainedsignificantly clinical efficacy. The quality of the literature incorporated is low, the conclusion requires high-qualityresearch to further prove. 展开更多
关键词 Shenqi Fuzheng GP chemotherapy Advanced non - small cell lung cancer Meta analysis
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A Singular Perturbation Method for Parametric Investigation on J-lay Installation of Deepwater Pipelines 被引量:3
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作者 王琴 段梦兰 +1 位作者 李海明 张庆元 《China Ocean Engineering》 SCIE EI CSCD 2013年第6期751-766,共16页
The maximum bending moment or curvature in the neighborhood of the touch down point (TDP) and the maximum tension at the top are two key parameters to be controlled during deepwater J-lay installation in order to en... The maximum bending moment or curvature in the neighborhood of the touch down point (TDP) and the maximum tension at the top are two key parameters to be controlled during deepwater J-lay installation in order to ensure the safety of the pipe-laying operation and the normal operation of the pipelines. In this paper, the non-linear governing differential equation for getting the two parameters during J-lay installation is proposed and solved by use of singular perturbation technique, from which the asymptotic expression of stiffened catenary is obtained and the theoretical expression of its static geometric configuration as well as axial tension and bending moment is derived. Finite element results are applied to verify this method. Parametric investigation is conducted to analyze the influences of the seabed slope, unit weight, flexural stiffness, water depth, and the pipe-laying tower angle on the maximum tension and moment of pipeline by this method, and the results show how to control the installation process by changing individual parameters. 展开更多
关键词 deepwater touch down point singular perturbation technique non-linear governing differential equation J-lay of pipeline geometric nonlinearity stiffened catenary
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