Moments and Mean First—Passage Time of Parabolic—Bistable Potential System Driven by Colored Noise

A parabolic-bistable potential system driven by colored noise is studied. The exact analytical expressions of the stationary probability distribution (SPD) and the moments of the system are derived. Furthermore, the mean first-passage time is calculated by the use of two approximate methods, respectively. It is found that (i) the double peaks of SPD are rubbed-down into a flat single peak with the increasing of noise intensity; (ii) a minimum occurs on the curve of the second-order moment of the system vs. noise intensity at the point ; (iii) the results obtained by our approximate approach are in good agreement with the numerical calculations for either small or large correlation time , while the conventional steepest descent approximation leads to poor results.

On the Meaning of the Number SEVEN in the Eastern and Western Culture

This paper interprets the connotation,denotation and the symbolic meaning of SEVEN from the perspective of semiotics.The number SEVEN means samsara,destiny,reincarnation,the ending and a brand new beginning,satisfaction after a lot of suffering in the East.While,in the West,besides these,it refers to the magic and holy power of the God,mystery,completeness and perfection,occult,happiness and luck.

Nature of the Quantum Potential

In this paper we suggested a natural interpretation of the de Broglie-Bohm quantum potential, as the energy due to the oscillating electromagnetic field (virtual photon) coupled with moving charged particle. Generalization of the Schr&oumldinger equation is obtained. The wave function is shown to be the eigenfunction of the Sturm-Liouville problem in which we expand virtual photon to include it implicitly into consideration. It is shown that the non-locality of quantum mechanics is related only with virtual photon. As an example, the zero-energy of harmonic oscillator is obtained from classical equations.

Generalization of iterative perturbation theory and coherent potential approximation (ITP+CPA) to double exchange model with orbital degeneracy

A combination of the iterative perturbation theory （ITP） of the dynamical mean field theory （DMFT） and coherentpotential approximation （CPA） is generalized to the double exchange model with orbital degeneracy. The Hubbard interaction and the off-diagonal components for the hopping matrix tij^mn（m ≠ n） are considered in our calculation of spectrum and optical conductivity. The numerical results show that the effects of the non-diagonal hopping matrix elements are important.

Solvent effects and potential of mean force study of the SN2 reaction of CH3F+CN-in water

We used a combined quantum mechanics and molecular mechanics （QM/MM） method to investigate the solvent effects and potential of mean force of the CH3F＋CN- reaction in water. Comparing to gas phase, the water solution substantially affects the structures of the stationary points along the reaction path. We quantitatively obtained the solvent effects＇ contributions to the reaction： 1.7 kcal/mol to the activation barrier and -26.0 kcal/mol to the reaction free energy. The potential mean of force calculated with the density functional theory/MM theory has a barrier height at 19.7 kcal/mol, consistent with the experimental result at 23.0 kcal/mol; the calculated reaction free energy at -43.5 kcal/mol is also consistent with the one estimated based on the gas-phase data at -39.7 kcal/mol.

Quantitative Description of Potential of Mean Force Between Macroparticles in Fluid with Attactive Forces

A statistical mechanics method is proposed for calculation of potential ofmean force (PMF). In the case of solvophobic or solvophilic macroparticles immersed in solvent bathof soft sphere or Lennard-Jones particles, prediction accuracy for the PMF and MF from the simplestimplementation of the proposed method, where hypernetted chain approximation is adopted forcorrelation of the macroparticle-macroparticle at infinitely dilute limit, is comparable to that ofa recent more sophisticated approach based on mixture Ornstein—Zernike integral equation / bridgefunction from fundamental measure functional. Adaptation of the present method for general complexQuids is discussed, and method for improving the accuracy is suggested. Differences and relativemerits of the present recipe compared with that based on potential distribution theory is discussed.

Different potential of mean force of two-state protein GB1 and downhill protein gpW revealed by molecular dynamics simulation

Two-state folding and down-hill folding are two kinds of protein folding dynamics for small single domain proteins.Here we apply molecular dynamics(MD)simulation to the two-state protein GB1 and down-hill folding protein gpW to reveal the relationship of their free energy landscape and folding/unfolding dynamics.Results from the steered MD simulations show that gpW is much less mechanical resistant than GB1,and the unfolding process of gpW has more variability than that of GB1 according to their force-extension curves.The potential of mean force(PMF)of GB1 and gpW obtained by the umbrella sampling simulations shows apparent difference:PMF of GB1 along the coordinate of extension exhibits a kink transition point where the slope of PMF drops suddenly,while PMF of gpW increases with extension smoothly,which are consistent with two-state folding dynamics of GB1 and downhill folding dynamics of gpW,respectively.Our results provide insight to understand the fundamental mechanism of different folding dynamics of twostate proteins and downhill folding proteins.

K^- Nucleus Elastic Scattering and Momentum-Dependent Optical Potentials

The K? nucleus differential elastic scattering cross section for 12C and 40Ca at is calculated with three momentum-dependent optical potential models, which are density-dependent, relativistic mean field, and hybrid model, respectively. It is found that the forms of momentum-dependent optical potential models proposed by us are reasonable and gain success in the calculations and the momentum-dependent hybrid model is the best model for the K? nucleus elastic scattering.

Influence of Solvent-Solvent and Solute-Solvent Interaction Properties on Solvent-Mediated Potential

A recently proposed universal calculational recipe for solvent-mediated potential is applied to calculate excess potential of mean force between two large Lennard-Jones (LJ) or hard core attractive Yukawa particles immersed in small LJ solvent bath at supercritical state. Comparison between the present prediction with a hypernetted chain approximation adopted for solute-solute correlation at infinitely dilute limit and existing simulation data shows high accuracy for the region with large separation, and qualitative reliability for the solute particle contact region. The calculational simplicity of the present recipe allows for a detailed investigation on the effect of the solute-solvent and solvent-solvent interaction details on the excess potential of mean force. The resultant conclusion is that gathering of solvent particles near a solute particle leads to repulsive excess PMF, while depletion of solvent particles away from the solute particle leads to attractive excess PMF, and minor change of the solvent-solvent interaction range has large influence on the excess PMF.

Mean-field potential calculations of high-pressure equation of state for BeO

A systematic study of the Hugoniot equation of state, phase transition, and the other thermodynamic properties including the Hugoniot temperature, the electronic and ionic heat capacities, and the Gruneisen parameter for shockcompressed BeO, has been carried out by calculating the total free energy. The method of calculations combines first-principles treatment for 0 K and finite-T electronic contribution and the mean-field-potential approach for the vibrational contribution of the lattice ion to the total energy. Our calculated Hugoniot is in good agreement with the experimental data.

基于相对联系数的区域水利高质量发展评价指标体系筛选方法

为综合判断在区域水利高质量发展目标、发展途径、发展条件相互作用下区域水资源-经济社会-生态环境复合系统不断协同优化的系统高质量发展水平状态,构建了由发展目标、发展途径和发展条件3个子系统组成的区域水利高质量发展初步评价指标体系。为定量分析初步评价指标体系的专家咨询信息,根据专家指标排序合理性模糊关系的取值区间特点提出了相对联系数,用相对联系数的平均集对势估计各专家指标排序合理性的权重,进而可得各指标重要性的专家综合排序值,据此筛选初步评价指标体系,构建了基于相对联系数的区域水利高质量发展评价指标体系筛选方法(SM-RCN)。SM-RCN在陕西省的应用结果表明:筛选后的指标体系汇聚了各专家对区域水利高质量发展主要影响指标的综合评判;SM-RCN可克服评价指标体系构建过程缺乏定量分析依据的不足,可识别不同专家、同一专家对不同评价方面的指标排序合理性的程度。该筛选方法在区域水利现代化、水资源空间均衡、水资源承载力等评价指标体系构建过程中具有应用前景。

Assessment of Nanothermodynamic Properties of Ferromagnetic Nanocluster in Subdivision Potential Approach and Magnetic Field

Using subdivision potential approach and mean-field theory for a ferromagnetic cluster, we obtained nanothermodynamic properties for a ferromagnetic nanocluster in the presence and also the absence of the magnetic field. The subdivision potential and the magnetic field both makes Gibbs and Helmholtz free energies of the ferromagnetic nanocluster stand at a lower level compared to those of the ferromagnetic cluster. Our main conclusion is that the presence of the magnetic field leads to decrease in the amount of specific heat capacity for the ferromagnetic cluster. On the other hand, this effect leads to increase in the amount of specific heat capacity for the ferromagnetic nanocluster.

Integrated Quantity, Quality and Ecology of County-Level Arable Land Improvement Potential Comprehensive Zoning: The Example of Tongxu County, China

The scientific evaluation of arable land remediation potential can be used to formulate remediation policies based on local conditions. This study took arable land resources in Tongxu County, China as the research object and administrative villages as the evaluation unit, constructed an evaluation index system by integrating three aspects—quantity, quality and ecology. Based on the evaluation of arable land remediation potential, the K-means++ spatial clustering algorithm combined with elbow method is used to divide the remediation partition and give the remediation strategy. The results showed that: 1) the evaluation index system of arable land improvement potential, which integrated “quantity-quality-ecology”, was more systematic in analyzing the potential of arable land improvement than the previous single target evaluation index, and explored its internal linkage. 2) There are some spatial differences in the quantitative, qualitative and ecological potentials in Tongxu County, with the quantitative potential being higher in Changzhi Township, the intersection of Lizhuang Township and the southern part of Yuhuangmiao Township, the qualitative potential being more evenly distributed, and the ecological potential being higher around Chengguan Township. 3) Through K-means++ clustering algorithm combined with elbow method, Tongxu County was divided into five subzones: quality improvement zone, intensive improvement zone, quantity improvement zone, comprehensive improvement zone and health improvement zone, among which the highest percentage of quality improvement zone and the lowest percentage of comprehensive improvement zone were 49.2% and 1.5% respectively, and differentiated remediation strategies were provided by research for each sub-district to promote high quality of arable land.

基于特征聚类的轨道不平顺潜在病害辨识

研究目的:轨道不平顺潜在病害隐蔽性强,对其准确合理辨识是开展预防修策略下线路养护维修作业的前提。本文以轨检数据为基础,分别构造了以轨道质量指数(TQI)和轨道不平顺幅值为对象的潜在病害辨识指标。在此基础上,基于k-means++聚类算法和手肘法通过判定样本最佳聚类簇数实现潜在病害的识别及定位。依托某有砟铁路动检数据对所提轨道不平顺潜在病害辨识方法进行了验证。研究结论:(1)对于均值管理来说,在16 km连续轨道区段上2处区段单元潜在病害被准确识别,其历史最大TQI值分别约为5.5 mm、5.3 mm,且潜在病害定位结果与实际里程基本吻合;(2)对于峰值管理来说,在500 m连续轨道区段上2处局部不平顺潜在病害也被准确识别,其历史最大幅值约为3 mm、3.3 mm,潜在病害定位结果与实际里程基本吻合;(3)本研究成果可与大机捣固作业、人工精调作业相结合,为预防修策略下的潜在病害整治提供辅助参考。

论符号现象学的形成

符号现象学的形成源自皮尔斯的符号思想理论体系。皮尔斯对现象问题的思考不仅奠定了符号学理论的基础,而且也为当今哲学符号学研究提供了重要的理论支撑。皮尔斯在其现象学手稿中清晰地论证了三种普遍范畴的存在方式与特性,以及三种范畴与人类意识活动之相互关系,这为探究文学艺术中日益凸显的意义与意识问题提供了理论资源。

生命的悲剧意识:关于“苦”的符号学漫谈

从符号学的视角看,悲剧意识赋予生命中的种种痛苦以意义,由此将这些苦“识别为”并“创造成”悲剧经验。悲剧现象可以从“历苦”(经验)、“知苦”(理解/阐释)、“述苦”(表征/再现)三个方面加以理解。这三个方面的划分,是以悲剧现象作为意义生成的具体例子而做出的。举凡意义生成,均发生在相对独立的个体身上,个体作为意义的主体和生成场而存在。“苦”与“消苦”的努力,也只能在主体上完成。因为符号活动,主体在意义生成的过程中,面临着“双重符号悖论”。但符号活动并非生命唯一必要的标准属性。对这一问题的反思,能够为理解生命的悲剧意识提供一个独特的切入点。

借助弱纹理匹配的TEDS车底故障区域定位算法

针对当前动车组运行故障动态图像检测系统(trouble of moving EMU detection system,TEDS)故障识别准确率低的问题,本文提出一种借助弱纹理匹配的动车底部潜在故障区域定位方法。首先,采用拓扑交叉数检测大量弱纹理区域特征点;然后,以特征点为中心的环形区域内各像素点的拓扑交叉数值筛选特征点,构建相应特征向量进行弱纹理特征匹配;最后,对配准后的图像进行比对定位潜在故障区域。实验结果表明,该算法保证了匹配精度,能检测出大部分潜在故障区域,弱纹理区域的特征匹配准确率超过80%且所有图像对均存在特征匹配对,为以后的精准故障分类提供了有利条件。

符号学的来龙去脉与基本原理综述

符号学是关于意义的学问。万事万物对于具有主体意识的人都是携带意义的“符号—物”双联体,人类社会的文化系统就是符号表意系统。对于符号问题的关注与研究,中西方都有着悠久的历史。现代符号学诞生于20世纪初,主要的创始人是瑞士的语言学家索绪尔与美国的哲学家皮尔斯。迄今,符号学有五种主要模式。20世纪20年代起,中国符号学在国际上发出了自己的声音,把符号定义为“意义的直观可感知的形式”。符号的功能在于表意。在人类社会中,符号发挥着不断积累与深化意义,持续建构社会文化的显在功能。符号都由两个基本部分构成:一是符号本体,二是符号伴随文本。

一种无阻流量预测方法

传统的预测无阻流量的方法是通过试气作业计算得到的,该方法作业周期长、资金投入大。但在气田勘探开发的初期,测井获得的大量参数可以有效反映出储层性质的优劣。本文建立一种测井参数与无阻流量的关系模型,采用Kmeans聚类分析方法对测井参数进行分析选取、预处理和转换;在此基础上,采用改进的ID3算法设计无阻流量预测算法,构建无阻流量决策树,形成单井目的层段的无阻流量判定方案。经过实验验证,该方法可以有效利用地质类数据预估无阻流量,预测单井产能,省略试气环节,加快气田投产进度,压缩开发成本,提高气田开发的经济效益。