用人工神经网络处理分光光度法和原子吸收光度法中非线性定量问题

本文利用ExtendedDelat－BarDelta（EDBD）算法的人工神经网络方法，对分光光度分析、流动注射分析及原子吸收3种典型体系中非线性定量关系进行了研究，对网络参数进行了优化，提出了适用于解决上述体系非线性定量关系的三种网络模型。结果表明，这些模型性能良好，预测精度高，为用人工种经网络解决扩大分析化学中的一些问题提供了一种新的手段，并使测试的应用范围扩大。

深部找矿非线性定量理论与技术方法研究进展综述

深部找矿前景的定量评价等研究内容已成为当前中国深部找矿工作中地质成矿理论研究的热点,大深度物探技术和深穿透的化探新方法、高分辨率航卫遥感技术以及大深度的钻探技术等方法的研制和应用已成为深部找矿技术的发展方向。文中提出和介绍了深部成矿作用的分形性质及混沌机制、分形小波多尺度分析方法、分形地质统计分析、深部找矿的物化探新技术方法。

非线性定量预测技术在渤南洼陷扇三角洲前缘砂体预测中的应用

针对渤南洼陷中深层扇三角洲前缘致密储层地震资料分辨率低、砂泥岩速度差异小、纵向含油层系多层薄、横向储层变化快、储层展布认识不清的难点,在地质沉积模式指导下,运用多体联合解释技术,建立地层等时格架,进行优势属性提取和分析。运用进化型神经网络技术,建立地震属性和砂地比的非线性关系,实现了对薄互层砂体的定量预测,预测结果既保证了与井点的吻合度,也保持了地震资料对沉积特征的反映能力。该方法可以为中深层薄互层储层预测提供借鉴,并指导了该块油藏开发。

脑死亡脑电非线性定量分析

目的:运用近似熵(ApEn)和C0复杂度对脑死亡患者脑电图(EEG)进行非线性定量分析,期望寻找一种可靠而又敏感的脑死亡诊断标准。方法:研究对象35例,其中男性21例,女性14例;年龄16～85岁。根据其临床表现和EEG结果分为脑死亡组、临床脑死亡组和非脑死亡组。对每组进行ApEn和C0复杂度分析,并比较3组结果。结果:脑死亡组患者17例,男性11例,女性6例;年龄21～82岁。临床脑死亡组5例,男性3例,女性2例;年龄16～85岁。非脑死亡组13例,男性7例,女性6例;年龄17～84岁。脑死亡组的ApEn值约为1.0,非脑死亡组的ApEn值约为0.3,临床脑死亡组ApEn值介于两者之间。脑死亡组C0复杂度值约为0.17,非脑死亡组C0复杂度值约为0.06,临床脑死亡组介于两者之间。无论是ApEn还是C0复杂度,数值上越接近脑死亡组者预后越差,反之越好。讨论:ApEn和C0复杂度对EEG进行非线性定量分析都是判定脑死亡较好的辅助检查。

低渗特低渗储层水锁损害定量预测方法

在低渗特低渗油气藏开发过程中储层损害严重,其中水锁损害是主要损害之一,因此建立准确、快速定量预测水锁损害程度的数学模型,对高效开发低渗透油田具有重要意义。采用线性回归分析法建立的水锁损害预测模型不能准确反映储层损害实质,预测精度较低。将常规线性回归模型转变为非线性回归模型,能够更好地反映各损害因素与损害程度间的关系;采用逐步回归法选择回归因子,建立了新的水锁损害定量预测模型,并对新模型进行了检验。结果表明,新建立的水锁损害定量预测模型预测结果准确性高,15组验证样本的预测准确率均大于80%,平均预测准确率为91.69%,可为油气层保护和储层解堵措施优化设计提供科学依据。

Determination of Melamine by Infrared Spectroscopy Based on Nonlinear Modeling

[Objective] The aim was to develop a nonlinear model of quantitative analysis of melamine content by infrared spectroscopy and provide theoretical basis for the nondestructive detection of melamine. [Method] According to dynamics,mathematical modeling and optimization theory,linear and nonlinear models were respectively set up by taking an absorption peak of 1 550 cm-1 as characteristic absorption peak. [Result] The correlation coefficient of nonlinear model was 0.922 7 and the recovery was 96%,which showed that the nonlinear model was more accurate than linearity model with correlation coefficient of 0.904 9 and recovery of 557%. [Conclusion] It is feasible to determine melamine content by using the nonlinear model quantitatively.

The Asymptotic Stability for a Class of Nonlinear Large Sceale System

This paper an cited instances in illustration of the incorrectness of the criteria of asymptotic stability of a class of nonlinear large seale system that L_j·T·Grujie gave in paper [1] by the comparison theory and then corrected it,and has given the sufficient conditions of the asymptotic stability.

DISCRETE BIDIRECTIONAL ASSOCIATIVE MEMORY WITH LEARNING FUNCTION

In this paper we propose a new discrete bidirectional associative memory (DBAM) which is derived from our previous continuous linear bidirectional associative memory (LBAM). The DBAM performs bidirectionally the optimal associative mapping proposed by Kohonen. Like LBAM and NBAM proposed by one of the present authors,the present BAM ensures the guaranteed recall of all stored patterns,and possesses far higher capacity compared with other existing BAMs,and like NBAM, has the strong ability to suppress the noise occurring in the output patterns and therefore reduce largely the spurious patterns. The derivation of DBAM is given and the stability of DBAM is proved. We also derive a learning algorithm for DBAM,which has iterative form and make the network learn new patterns easily. Compared with NBAM the present BAM can be easily implemented by software.

Quantitative similarity assessment of non-linear chemical fingerprint of traditional Chinese medicine by similarity system theory

The similarities of the non-linear chemical （NLC） fingerprints of Radix Glycyrrhizaes from four producing areas and eight other traditional Chinese medicines （TCMs） were calculated, using a systemic similarity calculation method proposed and three other main calculation ones （Euclidean distance, correlation coefficient and included angle cosine）. All of the correlation coefficient similarities of different TCMs are higher than 0.952, and the included angle cosines are all higher than 0.962. So, both the conelation coefficient and included angle cosine similarities are unable to be used as the criteria for quantitatively evaluating the similarities of NLC fingerprints of TCMs. Although all of the Euclidean distance similarities of Berry Liquorices from four producing areas are less than 73, those of the other eight TCMs are all more than 180. The Euclidean distance cannot reflect the relative magnitudes of the feature differences in the NLC fingerprints very correctly. The systemic similarity method is the best among the four ones. All of the systemic similarities of Berry Liquorices from the four producing areas are higher than 0.962, while those of the other eight TCMs are all lower than 0.805, and the systemic similarity can reflect the differences between samples most faithfully, and can be used as a quantitative one evaluating the similarities of NLC fingerprints of TCMs, by which TCM could be distinguished and evaluated quickly, simply and exactly.

Solitary Waves for Cubic-Quintic Nonlinear Schroedinger Equation with Variable Coefficients

The cubic-quintic nonlinear Schroedinger equation （CQNLS） plays important parts in the optical fiber and the nuclear hydrodynamics. By using the homogeneous balance principle, the bell type, kink type, algebraic solitary waves, and trigonometric traveling waves for the cubic-quintic nonlinear Schroedinger equation with variable coefficients （vCQNLS） are derived with the aid of a set of subsidiary high-order ordinary differential equations （sub-equations for short）. The method used in this paper might help one to derive the exact solutions for the other high-order nonlinear evolution equations, and shows the new application of the homogeneous balance principle.

A Model of Car-Following with Adaptive Headway

The performances of a well-known GHR car-following model was investigated by using numerical simulations in describing the acceleration and deceleration process induced by the motion of a leading car. It is shown that in GHR model vehicle is allowed to run arbitrarily close together if their speed are identical,and it waves aside even though the separation is larger than its desired distance. Based on these investigations, a modified GHR model which features a new nonlinear term which attempts to adjust the inter-vehicle spacing to a certain desired value was proposed accordingly to overcome these deficiencies. In addition, the analysis of the additive nonlinear term and steady-state flow of the new model were studied to prove its rationality.

Testing for Nonlinearity in Dynamic Characteristics of Vertical Upward Oil-Gas-Water Three-phase Bubble and Slug Flows

Based on the conductance fluctuation signals measured from vertical upward oil-gas-water three-phase flow experiment, time frequency representation and surrogate data method were used to investigate dynamical characteristics of oil-in-water type bubble and slug flows. The results indicate that oil-in-water type bubble flow will turn to deterministic motion with the increase of oil phase fraction f o and superficial gas velocity U sg under fixed flowrate of oil-water mixture Q mix . The dynamics of oil-in-water type slug flow becomes more complex with the increase of U sg under fixed flowrate of oil-water mixture. The change of f o leads to irregular influence on the dynamics of slug flow. These interesting findings suggest that the surrogate data method can be a faithful tool for characterizing dynamic characteristics of oil-in-water type bubble and slug flows.

Elliptic Function Waves of Spinor Bose-Einstein Condensates in an Optical Lattice

An improved nonlinear Schrodinger equation different from usual one of spinor Bose-Einstein condensates （BECs） in an optical lattice are obtained by taking into account a nonlinear term in the equation of motion for probability amplitude of spins carefully. The elliptic function wave solutions of the model are found under specific boundary condition, for example, the two ends of the atomic chain are fixed. In the case of limit the elliptic function wave solutions are reduced into spin-wave-like or solitons.

构建覆盖区综合地质找矿思路和流程的探索:以内蒙古锡林郭勒西北部为例

覆盖区矿产预测和地质找矿是一项具有探索性的研究课题,需要解决覆盖区各种致矿信息存在的"弱缓"、"叠加复合"、"缺失和不完整"等缺陷,从而有效地获得指示覆盖层之下矿化体的致矿信息.识别优势矿种和矿化类型、建立区域成矿-找矿模型,采用多重分形预测理论和方法,都将有利于强化和提取现有资料和数据中的致矿信息.提出了一个初步的覆盖区综合地质找矿流程框架,并结合实际研究工作认识,以内蒙古锡林郭勒西北部为例,介绍了采用这种覆盖区综合地质找矿流程进行草原覆盖区综合地质找矿的做法及其初步结果.

Non-linear and non-conservative quasi-variational principle of flexible body dynamics and application in spacecraft dynamics

The law of conservation of energy is one of the most fundamental laws of nature.According to the law of the conservation of energy,the non-linear and non-conservative quasi-variational principle of flexible body dynamics is established.The physical meaning of the quasi-stationary value conditions has been explained in non-linear and non-conservative flexible body dynamics.In the case study,the application in spacecraft dynamics is researched.

Blow-up phenomena of the vector nonlinear Schrdinger equations with magnetic fields

This paper is concerned with the finite time blow-up phenomena for the vector nonlinear Schrdinger equations with a magnetic field which describe the spontaneous generation of a magnetic field in a cold plasma in the subsonic limit. After obtaining some a priori estimates,we prove under certain natural conditions that the solutions to the Cauchy problem of the vector nonlinear Schrdinger equations in two and three spatial dimensions blow up in a finite time. Assuming that a solution to the aforementioned vector nonlinear Schrdinger equations is radially symmetric with respect to spatial variables x,we show that if the initial energy is non-positive,then the solution blows up in three dimensions in a finite time.

ASYMPTOTIC LIMITS AND STABILIZATION FOR THE 1D NONLINEAR MINDLIN-TIMOSHENKO SYSTEM

This paper shows how the so called von Karman model can be obtained as a singular limit of a modified Mindlin-Timoshenko system when the modulus of elasticity in shear κ tends to infinity, provided a regularizing term through a fourth order dispersive operator is added. Introducing damping mechanisms, the authors also show that the energy of solutions for this modified Mindlin-Timoshenko system decays exponentially, uniformly with respect to the parameter k. As κ→∞, the authors obtain the damped von Karman model with associated energy exponentially decaying to zero as well.

A generalized L_2-discrepancy for cubature and uncertainty quantification of nonlinear structures

The numerical method for multi-dimensional integrals is of great importance, particularly in the uncertainty quantification of engineering structures. The key is to generate representative points as few as possible but of acceptable accuracy. A generalized L2（GL2）-discrepancy is studied by taking unequal weights for the point set. The extended Koksma-Hlawka inequality is discussed. Thereby, a worst-case error estimate is provided by such defined GL2-discrepancy, whose dosed-form expression is available. The characteristic values of GL2-discrepancy are investigated. An optimal strategy for the selection of the representative point sets with a prescribed cardinal number is proposed by minimizing the GL2-discrepancy. The three typical examples of the multi-dimensional integrals are investigated. The stochastic dynamic response analysis of a nonlinear structure is then studied by incorporating the proposed method into the probability density evolution method. It is shown that the proposed method is advantageous in achieving tradeoffs between the efficiency and accuracy of the exemplified problems. Problems to be further studied are discussed.

STABILITY OF SWITCHED POLYNOMIAL SYSTEMS

This paper investigates the stability of （switched） polynomial systems. Using semi-tensor product of matrices, the paper develops two tools for testing the stability of a （switched） polynomial system. One is to convert a product of multi-variable polynomials into a canonical form, and the other is an easily verifiable sufficient condition to justify whether a multi-variable polynomial is positive definite. Using these two tools, the authors construct a polynomial function as a candidate Lyapunov function and via testing its derivative the authors provide some sufficient conditions for the global stability of polynomial systems.

Stabilization of an Euler-Bernoulli Beam with a Tip Mass Under the Unknown Boundary External Disturbances

This paper studies the stabilization problem of an Euler-Bernoulli beam with a tip mass,which undergoes unknown but uniform bounded disturbance at tip mass. Here the nonlinear feedback control law is used to cancel the effects of the external disturbances. For the controlled nonlinear system,the authors prove the well-posedness by the maximal monotone operator theory and the variational principle. Further the authors prove that the controlled nonlinear system is exponential stable by constructing a suitable Lyapunov function. Finally, some numerical simulations are given to support these results.