检索结果-南通市图书馆

AN INTEGRATION METHOD WITH FITTING CUBIC SPLINE FUNCTIONS TO A NUMERICAL MODEL OF 2ND-ORDER SPACE-TIME DIFFERENTIAL REMAINDER——FOR AN IDEAL GLOBAL SIMULATION CASE WITH PRIMITIVE ATMOSPHERIC equations

引用

Journal of Tropical Meteorology 2013年第4期19卷 388-396页

作者：辜旭赞张兵王明欢 Hubei Key Laboratory for Heavy Rain Monitoring and Warning Research Institute of Heavy Rain China Meteorological Administration

In this paper,the forecasting equations of a 2nd-order space-time differential remainder are deduced from the Navier-Stokes primitive equations and Eulerian operator by Taylor-series expansion.Here we introduce a cubic spline numerical model(Spline Model for short),which is with a quasi-Lagrangian time-split integration scheme of fitting cubic spline/bicubic surface to all physical variable fields in the atmospheric equations on spherical discrete latitude-longitude mesh.A new algorithm of"fitting cubic spline—time step integration—fitting cubic spline—……"is developed to determine their first-and2nd-order derivatives and their upstream points for time discrete integral to the governing equations in Spline Model.And the cubic spline function and its mathematical polarities are also discussed to understand the Spline Model’s mathematical foundation of numerical analysis.It is pointed out that the Spline Model has mathematical laws of"convergence"of the cubic spline functions contracting to the original functions as well as its 1st-order and 2nd-order derivatives.The"optimality"of the 2nd-order derivative of the cubic spline functions is optimal approximation to that of the original functions.In addition,a Hermite bicubic patch is equivalent to operate on a grid for a 2nd-order derivative variable field.Besides,the slopes and curvatures of a central difference are identified respectively,with a smoothing coefficient of 1/3,three-point smoothing of that of a cubic spline.Then the slopes and curvatures of a central difference are calculated from the smoothing coefficient 1/3 and three-point smoothing of that of a cubic spline,respectively.Furthermore,a global simulation case of adiabatic,non-frictional and"incompressible"model atmosphere is shown with the quasi-Lagrangian time integration by using a global Spline Model,whose initial condition comes from the NCEP reanalysis data,along with quasi-uniform latitude-longitude grids and the so-called"shallow atmosphere"Navier-Stokes primitive equations in the spherical coor

关键词： numerical forecast and numerical simulation 2nd-order space-time differential remainder numerical model cubic spline functions Navier-Stokes primitive equations quasi-Lagrangian time-split integration scheme global simulation case

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Establishment of fetal age equations based on ultrasound measurements in cross-bred Holstein cows

引用

Asian pacific Journal of Reproduction 2017年第4期6卷 186-190页

作者： Kanoknan Somnuk Pim Wannapakorn Waraporn Raksapol Bunlue Kornmatitsuk Sudsaijai Kornmatitsuk Department of Clinical Sciences and Public Health Faculty of Veterinary ScienceMahidol UniversityNakhon Pathom 73170Thailand

Objective:To establish fetal age equations based on ultrasound measurements in cross-bred Holstein cows in Thailand.Methods: The animals were bred for 30-120 d before pregnancy diagnosis using transrectal ultrasonography with real-time B-mode and specify 5 or 7.5 MHz linear array transducer. Parameters examined included crown rump length (CRL), trunk diameter (TrD) and eye diameter (ED).Results: One hundred and two cows had been examined, 80 of them were pregnant and contained at least one measurable characteristic as defined in the methods. Regression analysis and curve estimation were implied. The most frequently visualized parameters were TrD (42/80;52.50%) and CRL (41/80;51.25%) whereas ED (13/80;16.25%) was least frequently detected. In our study, the equations to estimate fetal age (indicated as Y) from CRL and TrD were established with very high correlation coefficients as follows, Y = 22.679+12.005 (CRL)-1.042 (CRL)2,R2 = 0.950, Pequations (CRL and TrD) and the ones embedded in the commercially available ultrasounds, the higher fetal age was estimated based on the same value of parameters (Pequations created in our study were from CRL and TrD.Conclusions: Comparing with others, Thai cross-bred fetus clearly showed slower growth rate and thus, to use our CRL's and TrD's equations for estimating fetal age seems more reliable than to use the ones embedded in the commercial ultrasounds.

关键词： Fetal age equations Ultrasound Cross-bred Holstein cows

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A New Method to Solve the Spheroidal Wave equations

引用

Chinese Physics Letters 2010年第3期27卷 40-43页

作者：田贵花 School of Science Beijing University of Posts and Telecommunications Beijing 100876

The perturbation method in supersymmetric quantum mechanics is used to study the spheroidal wave functions＇ eigenvalue problem. The super-potential are solved in series of the parameter α, and the general form of all its terms is obtained. This means that the spheroidal problem is solved completely in the way for the ground eigen-value problem. The shape invariance property is proved retained for the super-potential and subsequently all the excited eigen-value problem could be solved. The results show that the spheroidal wave equations are integrable.

关键词： Hive equipment Method equations

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Master equation,design equations and runaway speed of the Kaplan turbine

引用

Journal of Hydrodynamics 2021年第2期33卷 282-300页

作者： Zh.Zhang ZHAW Zurch University of Applied ScienceZurichSwitzerland

To make the Kaplan turbine technology comparable to both the Pelton and the Francis turbine,the master equation for the Kaplan turbine has been established by analyses similar to that-for the Francis turbine.The analysis begins with the descriptions of free vortex flows at the runner inlet and the swirl flow at the impeller exit.By considering the Euler equation for specific work and by further evaluating the most significant shock and swirling losses,the first and the second energy equations in the form of hydraulic efficiency were formulated.The master equation is then established by combining both energy equations.In addition,three design equations and a new design parameter are presented.The master equation relates the turbine hydromechanics to the geometrical design of both the runner and the guide-vane parameters.It enables the complete hydraulic characteristics of a given Kaplan turbine to be analytically and simply computed.A computation example demonstrates the functionality and applicability of the method.With the reconstructed master equation,the runaway speed of the Kaplan turbine and its dependence on the guide-vane setting can be easily and precisely computed.For bulb turbines with guide vanes directly ahead of the turbine runner in the same tube,all computations are also applicable using another equivalent control parameter.

关键词： Kaplan turbine master equation design equations design parameter runaway speed hydraulic efficiency shock loss swirling loss bulb turbines

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Uniform Convergence of the Solutions of Riccati equations for a Family of Optimal Control Problems

引用

Journal of Systems Science & Complexity 2020年第1期33卷 74-86页

作者： GE Zhaoqiang School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China

The uniform convergence of the solutions of a parameterized family of Riccati differential equations which arise in the context of optimal control problems for systems described by a family of linear time-varying evolution equations is considered on the infinite time interval in Hilbert space.Some sufficient conditions and an illustrative example are given for uniform convergence of the solutions of a family of the Riccati differential equations.The uniform convergence of the solutions of the Riccati differential equations with respect to parameters is important for applications to problems in adaptive control of stochastic evolution systems.

关键词： Hilbert space linear quadratic control problems Riccati differential equations timevarying evolution systems uniform convergence

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Novel Criteria for Exponential Stability of Linear Non-Autonomous Functional Differential equations

引用

Journal of Systems Science & Complexity 2019年第2期32卷 479-495页

作者： PHAM HUU ANH Ngoc THAI BAO Tran CAO THANH Tinh NGUYEN DINH Huy Department of Mathematics Vietnam National University-HCMC International University Faculty of Information Systems Vietnam National University-HCMC University of Information Technology Department of Mathematics Vietnam National University-HCMC University of Information Technology Division of Applied Mathematics Faculty of Applied Sciences Vietnam National University-HCMC Ho Chi Minh city University of Technology

General linear non-autonomous functional differential equations are considered. Explicit criteria for exponential stability are given. Furthermore, the authors present an explicit robust stability bound for systems su... 详细信息

关键词： Exponential stability linear functional differential equations perturbation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Well-Posedness of Fully Coupled Linear Forward-Backward Stochastic Differential equations

引用

Journal of Systems Science & Complexity 2019年第3期32卷 789-802页

作者： LIU Ruyi WU Zhen School of Mathematics and Zhongtai Securities Institute for Financial Studies Shandong University

This paper studies the well-posedness of fully coupled linear forward-backward stochastic differential equations (FBSDEs). The authors introduce two main methods-the method of continuation under monotonicity conditions and the unified approach-to ensure the existence and uniqueness of solutions of fully coupled linear FBSDEs. The authors show that the first method (the method of continuation under monotonicity conditions) can be deduced as a special case of the second method (the unified approach). An example is given to illustrate it in linear FBSDEs case. And then, a linear transformation method in virtue of the non-degeneracy of transformation matrix is introduced for cases that the linear FBSDEs can not be dealt with by the the method of continuation under monotonicity conditions and the unified approach directly. As a powerful supplement to the the method of continuation under monotonicity conditions and the unified approach, linear transformation method overall develops the well-posedness theory of fully coupled linear forward-backward stochastic differential equations which have potential applications in optimal control and partial differential equation theory.

关键词： Forward-backward stochastic differential equations linear transformation monotonicity conditions optimal control theory unified approach

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Resonant multiple wave solutions to some integrable soliton equations

引用

Chinese Physics B 2019年第11期28卷 92-98页

作者：刘建根杨小军冯忆颖 School of Mathematics China University of Mining and TechnologyXuzhou 221116China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 221116China

To transform the exponential traveling wave solutions to bilinear differential equations, a sufficient and necessary condition is proposed. Motivated by the condition, we extend the results to the(2+1)-dimensional Kadomtsev–Petviashvili(KP) equation, the(3+1)-dimensional generalized Kadomtsev–Petviashvili(g-KP) equation, and the B-type Kadomtsev–Petviashvili(BKP) equation. Aa a result, we obtain some new resonant multiple wave solutions through the parameterization for wave numbers and frequencies via some linear combinations of exponential traveling waves. Finally, these new resonant type solutions can be displayed in graphs to illustrate the resonant behaviors of multiple wave solutions.

关键词： linear superposition principle resonant multiple wave solutions (2+1)-dimensional Kadomtsev–Petviashvili(KP) equation (3+1)-dimensional g-KP and BKP equations

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Multiple Soliton Solutions of Alice–Bob Boussinesq equations

引用

Chinese Physics Letters 2019年第5期36卷 22-26页

作者：李辉楼森岳 School of Physical Science and Technology Ningbo University Shanghai Key Laboratory of Trustworthy Computing East China Normal University

Three Alice-Bob Boussinesq(ABB) nonlocal systems with shifted parity■, delayed time reversal■ and ■ nonlocalities are investigated. The multi-soliton solutions of these models are systematically found from the ■ symmetry reductions of a coupled local Boussinesq system. The result shows that for ABB equations with ■ nonlocality, an odd number of solitons is prohibited. The solitons of the ■ nonlocal ABB and ■ nonlocal ABB equations must be paired, while any number of solitons is allowed for the ■ nonlocal ABB system. t-breathers, x-breathers and rogue waves exist for all three types of nonlocal ABB system.In particular, different from classical local cases, the first-order rogue wave can have not only four leaves but also five and six leaves.

关键词： ABB Bob Boussinesq equations Multiple Soliton Solutions of Alice

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Asymmetric and Single-Side Splitting of Dissipative Solitons in Complex Ginzburg–Landau equations with an Asymmetric Wedge-Shaped Potential

引用

Chinese Physics Letters 2019年第1期36卷 24-27页

作者：廖云程刘彬刘娟陈佳 National Engineering Laboratory for Destructive Testing and Optoelectronic Sensing Technology and Application Nanchang HangKong University Nanchang Institute of Science and Technology

We report some novel dynamical phenomena of dissipative solitons supported by introducing an asymmetric wedge-shaped potential(just as a sharp ‘razor') into the complex Ginzburg–Landau equation with the cubicquintic nonlinearity. The potentials corresponding to a local refractive index modulation with breaking symmetry can be realized in an active optical medium with respective expanding antiwaveguiding structures. Using the razor potential acting on a central dissipative soliton, possible outcomes of asymmetric and single-side splitting of dissipative solitons are achieved with setting different strengths and steepness of the potentials. The results can potentially be used to design a multi-route splitter for light beams.

关键词： Dissipative Solitons Complex Ginzburg-Landau equations Asymmetric Wedge-Shaped Potential

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：