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Several Results on the Number of Zeroes of Nonlinear Mappings on Bounded Regions
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作者 高堂安 王则柯 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第1期44-47,共4页
With homotopy methods, this paper discusses the existence and the number of zeroes of nonlinear mappings on bounded regions and extends some classical theorems.
关键词 HOMOTOPY nonlinear mapping
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Condition Monitoring of Turbines Using Nonlinear Mapping Method
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作者 LiaoGuang-lan ShiTi-lin JiangNan 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第2期225-228,共4页
Aiming at the non-linear nature of the signals generated from turbines, curvilinear component analysis (CCA), a novel nonlinear projection method that favors local topology conservation is presented for turbines condi... Aiming at the non-linear nature of the signals generated from turbines, curvilinear component analysis (CCA), a novel nonlinear projection method that favors local topology conservation is presented for turbines conditions monitoring. This is accomplished in two steps. Time domain features are extracted from raw vibration signals, and then they are projected into a two-dimensional output space by using CCA method and form regions indicative of specific conditions, which helps classify and identify turbine states visually. Therefore, the variation of turbine conditions can be observed clearly with the trajectory of image points for the feature data in the two-dimensional space, and the occurrence and development of failures can be monitored in time. Key words condition monitoring - turbines - nonlinear mapping - curvilinear component analysis CLC number TP 17 - TH 17 Foundation item: Supported by the National Key Basic Research Special Found of China (2003CB716207) and the National Natural Science Foundation of China (50375047)Biography: Liao Guang-lan (1974-), male, Ph. D. candidate, research direction: fault diagnosis, pattern recognition and neural networks. 展开更多
关键词 condition monitoring turbines nonlinear mapping curvilinear component analysis
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Seismic-inversion method for nonlinear mapping multilevel well–seismic matching based on bidirectional long short-term memory networks
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作者 Yue You-Xi Wu Jia-Wei Chen Yi-Du 《Applied Geophysics》 SCIE CSCD 2022年第2期244-257,308,共15页
In this paper,the recurrent neural network structure of a bidirectional long shortterm memory network(Bi-LSTM)with special memory cells that store information is used to characterize the deep features of the variation... In this paper,the recurrent neural network structure of a bidirectional long shortterm memory network(Bi-LSTM)with special memory cells that store information is used to characterize the deep features of the variation pattern between logging and seismic data.A mapping relationship model between high-frequency logging data and low-frequency seismic data is established via nonlinear mapping.The seismic waveform is infinitely approximated using the logging curve in the low-frequency band to obtain a nonlinear mapping model of this scale,which then stepwise approach the logging curve in the high-frequency band.Finally,a seismic-inversion method of nonlinear mapping multilevel well–seismic matching based on the Bi-LSTM network is developed.The characteristic of this method is that by applying the multilevel well–seismic matching process,the seismic data are stepwise matched to the scale range that is consistent with the logging curve.Further,the matching operator at each level can be stably obtained to effectively overcome the problems that occur in the well–seismic matching process,such as the inconsistency in the scale of two types of data,accuracy in extracting the seismic wavelet of the well-side seismic traces,and multiplicity of solutions.Model test and practical application demonstrate that this method improves the vertical resolution of inversion results,and at the same time,the boundary and the lateral characteristics of the sand body are well maintained to improve the accuracy of thin-layer sand body prediction and achieve an improved practical application effect. 展开更多
关键词 bidirectional recurrent neural networks long short-term memory nonlinear mapping well–seismic matching seismic inversion
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WEYL TRANSFORMATIONS ON MANIFOLDS Ⅱ. Generalized Trace and Inverse Mapping Formula
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作者 钱敏 许连超 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1992年第4期289-297,共9页
The two gate formula for a diffusion X_t in R^n is considered.The formula gives an expressionof the density function of X_t in terms of the path integral of the Brownian bridge starting from xand ending on y at time t.
关键词 WEYL TRANSFORMATIONS ON MANIFOLDS Generalized Trace and inverse mapping Formula
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THE MAPPING RELATION AMONG SOLUTION OF SOME NONLINEAR EQUATIONS 被引量:1
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作者 倪光炯 楼森岳 《Acta Mathematica Scientia》 SCIE CSCD 1989年第2期131-141,共11页
Among the solutions of three kinds of nonlinear equations in one dimensional systems, cubic nonlinear Klein-Gordon (including Φ~4), Sine-Gordon and double Sine-Gordon, some mapping relations exist. When a solution of... Among the solutions of three kinds of nonlinear equations in one dimensional systems, cubic nonlinear Klein-Gordon (including Φ~4), Sine-Gordon and double Sine-Gordon, some mapping relations exist. When a solution of any one equation is known, so are the other two. 展开更多
关键词 DSG THE mapping RELATION AMONG SOLUTION OF SOME nonlinear EQUATIONS
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Block and parallel modelling of broad domain nonlinear continuous mapping based on NN
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作者 Yang Guowei Tu Xuyan Wang Shoujue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期586-592,共7页
The necessity of the use of the block and parallel modeling of the nonlinear continuous mappings with NN is firstly expounded quantitatively. Then, a practical approach for the block and parallel modeling of the nonli... The necessity of the use of the block and parallel modeling of the nonlinear continuous mappings with NN is firstly expounded quantitatively. Then, a practical approach for the block and parallel modeling of the nonlinear continuous mappings with NN is proposed. Finally, an example indicating that the method raised in this paper can be realized by suitable existed software is given. The results of the experiment of the model discussed on the 3-D Mexican straw hat indicate that the block and parallel modeling based on NN is more precise and faster in computation than the direct ones and it is obviously a concrete example and the development of the large-scale general model established by Tu Xuyan. 展开更多
关键词 model nonlinear continuous mapping neural network parallel modelling.
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Extended Mapping Transformation Method and Its Applications to Nonlinear Partial Differential Equation(s)
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作者 ZHAO Hong BAI Cheng-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3X期473-478,共6页
In this paper, we extend the mapping transformation method through introducing variable coefficients.By means of the extended mapping transformation method, many explicit and exact general solutions with arbitrary fun... In this paper, we extend the mapping transformation method through introducing variable coefficients.By means of the extended mapping transformation method, many explicit and exact general solutions with arbitrary functions for some nonlinear partial differential equations, which contain solitary wave solutions, trigonometric function solutions, and rational solutions, are obtained. 展开更多
关键词 nonlinear partial differential equations extended mapping transformation method exact solutions
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Variable-Coefficient Mapping Method Based on Elliptical Equation and Exact Solutions to Nonlinear SchrSdinger Equations with Variable Coefficient
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作者 GE Jian-Ya WANG Rui-Min +1 位作者 DAI Chao-Qing ZHANG Jie-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4X期656-662,共7页
In this paper, by means of the variable-coefficient mapping method based on elliptical equation, we obtain explicit solutions of nonlinear Schrodinger equation with variable-coefficient. These solutions include Jacobi... In this paper, by means of the variable-coefficient mapping method based on elliptical equation, we obtain explicit solutions of nonlinear Schrodinger equation with variable-coefficient. These solutions include Jacobian elliptic function solutions, solitary wave solutions, soliton-like solutions, and trigonometric function solutions, among which some are found for the first time. Six figures are given to illustrate some features of these solutions. The method can be applied to other nonlinear evolution equations in mathematical physics. 展开更多
关键词 variable-coefficient mapping method based on elliptical equation nonlinear Schrodinger equation Jacobian elliptic function solutions solitonic solutions trigonometric function solutions
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A new system of nonlinear variational inequalities with relaxed cocoercive mappings in reflexive Banach spaces
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作者 潘显兵 《Journal of Chongqing University》 CAS 2011年第3期139-146,共8页
A new system for relaxed cocoercive non-linear variational inequalities in uniformly smooth Banach spaces is introduced and studied using the convergence of projection methods.Our results generalize and improve the co... A new system for relaxed cocoercive non-linear variational inequalities in uniformly smooth Banach spaces is introduced and studied using the convergence of projection methods.Our results generalize and improve the corresponding results of recent works. 展开更多
关键词 nonlinear variational inequality relaxed cocoercive mapping projection method convergence of projection method
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Algorithm of solutions for generalized nonlinear implicit quasivariational inclusions with fuzzy mappings
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作者 胡学刚 《Journal of Chongqing University》 CAS 2006年第1期36-41,共6页
A class of generalized implicit quasivariational inclusions with fuzzy mappings in Hilbert space is discussed in this paper which proves an existence theorem of the solutions and proposes a new iterative algorithm and... A class of generalized implicit quasivariational inclusions with fuzzy mappings in Hilbert space is discussed in this paper which proves an existence theorem of the solutions and proposes a new iterative algorithm and the convergence of the iterative sequence generated by the new algorithm. These results extend and improve some recent corresponding achievements. 展开更多
关键词 generalized nonlinear implicit quasivariational inclusion with fuzzy mappings existence theorem of solutions ITERATIVE
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COHERENT STATES, INVERSE MAPPING FORMULA FOR WEYL TRANSFORMATIONS AND APPLICATION TO EQUATIONS OF KdV TYPE
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作者 钱敏 徐平 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1990年第3期193-204,共12页
In this paper, we consider the trace of generalized operators and inverse Weyl transformation.First of all we repeat the definition of test operators and generalized operators given in [18],denoting L~2(R) by H.
关键词 COHERENT STATES inverse mapping FORMULA FOR WEYL TRANSFORMATIONS AND APPLICATION TO EQUATIONS OF KdV TYPE
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Strong convergence theorem for relatively nonexpansive mapping and inverse-strongly-monotone mapping in a Banach space
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作者 刘英 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第7期925-932,共8页
In this paper, we introduce an iterative sequence for finding a common element of the set of fixed points of a relatively nonexpansive mapping and the set of solutions of the variational inequality for an inverse-stro... In this paper, we introduce an iterative sequence for finding a common element of the set of fixed points of a relatively nonexpansive mapping and the set of solutions of the variational inequality for an inverse-strongly-monotone mapping in a Banach space. Then, we show that the sequence converges strongly to a common element of the two sets. Our results improve and extend the corresponding results reported by many others. 展开更多
关键词 relatively nonexpansive mapping generalized projection inverse-strongly-monotone variational inequality p-uniformly convex
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The homotopic mapping method for sea-air oscillator model of interdecadal climate fluctuations 被引量:9
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作者 莫嘉琪 林一骅 王辉 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第12期2387-2390,共4页
The E1 Nifio/La Nifia Southern Oscillation (ENSO) is an interannual phenomenon involved in the tropical Pacific ocean-atmosphere interactions. In this paper, a coupled system of sea-air oscillator model is studied. ... The E1 Nifio/La Nifia Southern Oscillation (ENSO) is an interannual phenomenon involved in the tropical Pacific ocean-atmosphere interactions. In this paper, a coupled system of sea-air oscillator model is studied. The aim is to create an asymptotic solving method of nonlinear equation for the ENSO model. And based on a class of oscillators of ENSO model, employing the method of homotopic mapping, the approximate solution of corresponding problem is studied. It is proven from the results that the homotopic method can be used for analysing the sea surface temperature anomaly in the equatorial eastern Pacific and the thermocline depth anomaly of the atmosphere-ocean oscillation for ENSO model. 展开更多
关键词 nonlinear homotopic mapping E1 Nifio-Southern oscillator model
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T1 mapping技术原理及其在心肌定量的研究进展 被引量:5
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作者 贾韬宇 秦培鑫 +4 位作者 扈锋 周小兵 鲁玲 潘存雪 李绍林 《磁共振成像》 CAS CSCD 北大核心 2022年第3期151-158,共8页
心脏磁共振成像中的纵向弛豫时间定量(T1 mapping)技术是一种直观的无创性评价心肌组织特性的影像检查方法,可以提供多种定量参数用于心肌病的诊断、鉴别诊断以及预后评价。T1 mapping技术由准备脉冲和读出序列两部分组成,在其近20年的... 心脏磁共振成像中的纵向弛豫时间定量(T1 mapping)技术是一种直观的无创性评价心肌组织特性的影像检查方法,可以提供多种定量参数用于心肌病的诊断、鉴别诊断以及预后评价。T1 mapping技术由准备脉冲和读出序列两部分组成,在其近20年的技术发展过程中,研究者对这两部分进行了持续不断的优化。本文分别对三种准备脉冲(反转恢复准备脉冲、饱和恢复准备脉冲以及两者组合的准备脉冲)和两种读出序列(平衡稳态自由进动序列和快速小角度激发序列)各自的优化发展进程以及临床应用进行综述,并以三种不同准备脉冲T1 mapping技术中的代表性序列为例进行成像原理说明。 展开更多
关键词 心脏磁共振 纵向弛豫时间定量 改良Look-Lock反转恢复技术 饱和恢复单激发采集技术 平衡稳态自由进动序列 快速小角度激发序列 细胞外容积 心肌病
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Mapping equivalent approach to analysis and realization of memristor-based dynamical circuit 被引量:3
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作者 包伯成 胡丰伟 +1 位作者 刘中 许建平 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期303-310,共8页
A novel mapping equivalent approach is proposed in this paper, which can be used for analyzing and realizing a memristor-based dynamical circuit equivalently by a nonlinear dynamical circuit with the same topologies a... A novel mapping equivalent approach is proposed in this paper, which can be used for analyzing and realizing a memristor-based dynamical circuit equivalently by a nonlinear dynamical circuit with the same topologies and circuit parameters. A memristor-based chaotic circuit and the corresponding Chua's chaotic circuit with two output differentiators are taken as examples to illustrate this approach. Equivalent dynamical analysis and realization of the memristor-based chaotic circuit are performed by using Chua's chaotic circuit. The results indicate that the outputs of memristor-based chaotic circuit and the corresponding outputs of Chua's chaotic circuit have identical dynamics. The proposed approach verified by numerical simulations and experimental observations is useful in designing and analyzing memristor-based dynamical circuits. 展开更多
关键词 dynamics mapping equivalent approach MEMRISTOR nonlinear circuit
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SOME RESULTS ON GENERALIZED EQUILIBRIUM PROBLEMS INVOLVING STRICTLY PSEUDOCONTRACTIVE MAPPINGS 被引量:8
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作者 Jong Kyu Kim Sun Young Cho 《Acta Mathematica Scientia》 SCIE CSCD 2011年第5期2041-2057,共17页
In this paper,we consider an iterative sequence for generalized equilibrium problems and strictly pseudocontractive mappings.We show that the iterative sequence converges strongly to a common element of the solution s... In this paper,we consider an iterative sequence for generalized equilibrium problems and strictly pseudocontractive mappings.We show that the iterative sequence converges strongly to a common element of the solution set of generalized equilibrium problems and of the fixed point set of strictly pseudocontractive mappings. 展开更多
关键词 equilibrium problem nonexpansive mapping inverse-strongly monotone mapping strictly pseudocontractive mapping
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Weighted total variation using split Bregman fast quantitative susceptibility mapping reconstruction method 被引量:1
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作者 Lin Chen Zhi-Wei Zheng +4 位作者 Li-Jun Bao Jin-Sheng Fang Tian-He Yang Shu-Hui Cai Cong-Bo Cai 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期645-654,共10页
An ill-posed inverse problem in quantitative susceptibility mapping (QSM) is usually solved using a regularization and optimization solver, which is time consuming considering the three-dimensional volume data. Howe... An ill-posed inverse problem in quantitative susceptibility mapping (QSM) is usually solved using a regularization and optimization solver, which is time consuming considering the three-dimensional volume data. However, in clinical diagnosis, it is necessary to reconstruct a susceptibility map efficiently with an appropriate method. Here, a modified QSM reconstruction method called weighted total variation using split Bregman (WTVSB) is proposed. It reconstructs the susceptibility map with fast computational speed and effective artifact suppression by incorporating noise-suppressed data weighting with split Bregman iteration. The noise-suppressed data weighting is determined using the Laplacian of the calculated local field, which can prevent the noise and errors in field maps from spreading into the susceptibility inversion. The split Bregman iteration accelerates the solution of the Ll-regularized reconstruction model by utilizing a preconditioned conjugate gradient solver. In an experiment, the proposed reconstruction method is compared with truncated k-space division (TKD), morphology enabled dipole inversion (MEDI), total variation using the split Bregman (TVSB) method for numerical simulation, phantom and in vivo human brain data evaluated by root mean square error and mean structure similarity. Experimental results demonstrate that our proposed method can achieve better balance between accuracy and efficiency of QSM reconstruction than conventional methods, and thus facilitating clinical applications of QSM. 展开更多
关键词 quantitative susceptibility mapping ill-posed inverse problem noise-suppressed data weighting split Bregman iteration
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A NEW ITERATIVE METHOD FOR FINDING COMMON SOLUTIONS OF GENERALIZED EQUILIBRIUM PROBLEM,FIXED POINT PROBLEM OF INFINITE k-STRICT PSEUDO-CONTRACTIVE MAPPINGS,AND QUASI-VARIATIONAL INCLUSION PROBLEM 被引量:5
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作者 刘敏 张石生 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期499-519,共21页
In this article, we introduce a hybrid iterative scheme for finding a common element of the set of solutions for a generalized equilibrium problems, the set of common fixed point for a family of infinite k-strict pseu... In this article, we introduce a hybrid iterative scheme for finding a common element of the set of solutions for a generalized equilibrium problems, the set of common fixed point for a family of infinite k-strict pseudo-contractive mappings, and the set of solutions of the variational inclusion problem with multi-valued maximal monotone mappings and inverse-strongly monotone mappings in Hilbert space. Under suitable conditions, some strong convergence theorems are proved. Our results extends the recent results in G.L.Acedo and H.K.Xu [2], Zhang, Lee and Chan [8], Wakahashi and Toyoda [9], Takahashi and Takahashi [I0] and S. S. Chang, H. W. Joseph Lee and C. K. Chan [II], S.Takahashi and W.Takahashi [12]. Moreover, the method of proof adopted in this article is different from those of [4] and [12]. 展开更多
关键词 k-strict pseudo-contractive mappings generalized equilibrium problem vis-cosity approximation method variational inclusion problem multi-valuedmaximal monotone mappings s-inverse-strongly monotone mapping
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Neuro-Space Mapping for Modeling Heterojunction Bipolar Transistor 被引量:1
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作者 闫淑霞 成千福 +1 位作者 邬海峰 张齐军 《Transactions of Tianjin University》 EI CAS 2015年第1期90-94,共5页
A neuro-space mapping(Neuro-SM) for modeling heterojunction bipolar transistor(HBT) is presented, which can automatically modify the input signals of the given model by neural network. The novel Neuro-SM formulations ... A neuro-space mapping(Neuro-SM) for modeling heterojunction bipolar transistor(HBT) is presented, which can automatically modify the input signals of the given model by neural network. The novel Neuro-SM formulations for DC and small-signal simulation are proposed to obtain the mapping network. Simulation results show that the errors between Neuro-SM models and the accurate data are less than 1%, demonstrating that the accurcy of the proposed method is higher than those of the existing models. 展开更多
关键词 heterojunction bipolar transistor (HBT) nonlinear device modeling neural network neuro-space mapping OPTIMIZATION
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Mapping of an Approximate Neutral Density Surface with Ungridded Data 被引量:1
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作者 YOU Yuzhu 《Journal of Ocean University of China》 SCIE CAS 2008年第1期1-9,共9页
A neutral density surface is a logical study frame for water-mass mixing since water parcels spread along such a surface without doing work against buoyancy restoring force. Mesoscale eddies are believed to stir and s... A neutral density surface is a logical study frame for water-mass mixing since water parcels spread along such a surface without doing work against buoyancy restoring force. Mesoscale eddies are believed to stir and subsequently mix predominantly along such surfaces. Because of the nonlinear nature of the equation of state of seawater, the process of accurately mapping a neutral density surface necessarily involves lateral computation from one conductivity, temperature and depth (CTD) cast to the next in a logical sequence. By contrast, the depth of a potential density surface on any CTD cast is found solely from the data on this cast. The lateral calculation procedure causes a significant inconvenience. In a previous paper by present author published in this journal (You, 2006), the mapping of neutral density surfaces with regularly gridded data such as Levitus data has been introduced. In this note, I present a new method to find the depth of a neutral density surface from a cast without having to specify an integration path in space. An appropriate reference point is required that is on the neutral density surface and thereafter the neutral density surface can be de- termined by using the CTD casts in any order. This method is only approximate and the likely errors can be estimated by plotting a scatter diagram of all the pressures and potential temperatures on the neutral density surfaces. The method assumes that the variations of potential temperature and pressure (with respect to the values at the reference point) on the neutral density surface are proportional. It is important to select the most appropriate reference point in order to approximately satisfy this assumption, and in practice this is found by inspecting the θ-p plot of data on the surface. This may require that the algorithm be used twice. When the straight lines on the θ-p plot, drawn from the reference point to other points on the neutral density surface, enclose an area that is external to the clus- ter of θ-p points of the neutral density surface, errors will occur, and these errors can be quantified from this diagram. Examples showing the use of the method are presented for each of the world’s main oceans. 展开更多
关键词 neutral density surface McDougall Surface mapping of a neutral density surface nonlinear equation of state of sea water ungridded data water-mass mixing world oceans
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