一种改进的粒子群优化算法

提出了一种改进的PSO(粒子群优化)算法,该算法在基本PSO算法的粒子位置更新公式中增加了一个积分控制项,积分控制项根据每个粒子的适应值决定粒子位置的变化,改善了PSO算法摆脱局部极小点的能力。另外,在该算法中粒子行为是基于个体极值中心点和全局极值点确定的,这使得粒子能够获得更多的信息量来调整自身状态。用3个基准函数对新算法进行了实验,结果表明新算法优于已有的一些改进PSO算法。     

基于信赖域技术的局部收缩的微粒群算法

为了改善标准的微粒群优化算法(SPSO)的性能,给出一个新的速度更新策略——局部收缩策略,且把信赖域技术引入PSO算法中进行惯性权重的动态调整,提出一个新的微粒群优化算法——基于信赖域技术的局部收缩的微粒群算法.新算法(NPSO)保持了PSO算法结构简单的特点,改善了PSO算法的全局寻优能力,提高了算法的收敛速度和计算精度.利用10个测试函数测试新算法的性能,并分别与SPSO、与混沌相结合的微粒群算法(PSOC)、具有被动聚集的微粒群算法(PSOPC)、SPSO的全局版本及带有收缩因子的微粒群算法(CPSO)比较,实验结果表明,新算法(NPSO)大大地改善了实例测试函数的表现.       

基于自适应随机惯性权的粒子群优化算法

分析惯性权值对粒子群优化算法(PSO)优化性能的影响,提出了基于自适应随机惯性权(ARIW)的改进粒子群优化算法.在进化过程中,为粒子群中的各个粒子随机选取惯性权值,并随进化代数自适应地调整随机惯性权值的概率分布.使用四个基准函数进行测试,结果表明基于ARIW的PSO算法不但计算简便,而且能有效地调整算法全局与局部的搜索能力,显著提高了全局搜索的速度与精度.     

改进PSO 算法在振荡式注汽速度优化中的应用

针对蒸汽驱恒定式注汽速度驱油效果差的现状,提出了一种基于改进PSO( Particle Swarm Optimization) 算法的蒸汽驱振荡式注汽速度优化方法。该方法建立了蒸汽驱注汽速度数学模型,采用改进粒子群优化算法对此模型进行求解并优化振荡式注汽速度,最后得到蒸汽驱振荡式注汽速度最优方案。改进粒子群优化算法引入混沌优化算子产生初始解,依据各粒子适应值的距离,完成对各个粒子的自适应变异,同时引入极值扰动算子对个体历史最优值和全局最优值实施随机扰动,加快了收敛速度,提高了种群的可进化能力。实验结果表明: 所建立模型准确,优化算法有效。通过此方法可指导蒸汽驱注采方案合理编制,指导蒸汽驱高效运行。     

三群协同粒子群优化算法

针对基本粒子群优化算法易陷入局部极值点、搜索精度低等缺点,提出了一种三群协同粒子群优化算法(TSC-PSO)。搜索时,如果全局极值连续若干代没有改善,粒子未找到全局最优点,就任选某个优群,将其群内粒子和差群粒子交换。仿真结果显示,对一些经典多峰值函数、非凸病态函数,TSC-PSO增强了全局搜索能力,具有比基本PSO更好的优化性能。     

基于变邻域搜索改进的冲突解脱粒子群算法

飞行冲突解脱是航空器安全运行的关键,粒子群优化(particle swarm optimization,PSO)算法和变邻域搜索(variable neighborhood search,VNS)算法都可以用于解决飞行冲突,但PSO算法接近最优解时收敛速度降低,VNS算法的全局搜索能力较差。为融合PSO算法全局搜索的快速收敛特性和VNS算法的局部搜索能力,提出了变邻域搜索改进的粒子群优化算法。仿真结果证明该算法能够快速搜索到全局最优解,继承了二者的优势,同时提高了最终解脱航迹的适应值,并减少了收敛时间。     

一种融合梯度信息的粒子群优化算法

针对粒子群优化算法(PSO)存在盲目搜索、收敛速度慢的问题，提出一种融合梯度信息的改进粒子群优化算法，简记为GIPSO(Gradient Information based PSO)。利用目标函数的梯度信息指导粒子朝着适应值更低的方向搜索，可有效避免粒子的盲目搜索行为。首先，在线性权重粒子群算法的进化公式中嵌入目标函数的梯度信息，有效提升了改进方法的收敛精度；其次，随机选择一半的粒子使用含有梯度信息的速度进化公式以降低算法的计算量，在标准测试函数上的仿真实验结果表明，GIPSO算法在收敛速度与收敛精度方面，均优于基本PSO算法，线性权重衰减PSO算法，正太分布权重PSO算法等传统方法。     

一个与信籁域搜索技术相结合的微粒群算法

微粒群优化算法(PSO)是一种有效的随机全局优化技术.文章针对利用微粒群优化算法进行多极值点的函数优化时,存在陷入局部极小点和搜索效率低的问题,把信籁域搜索技术引入到PSO算法中,提出了基于信籁域搜索的微粒群优化算法(TRPSO).该算法保持了PSO算法结构简单的特点,改善了PSO算法的全局寻优能力,提高了算法的收敛速度和计算精度.仿真计算结果表明,该算法的性能优于混沌微粒群优化算法(CPSO)和基本微粒群优化算法(PSO).     

基于增量式PID的改进粒子群算法

基于粒子群优化(PSO)算法的简单模型和增量式PID控制原理,引入PID增量算子和4个新随机因子,对标准粒子群优化(SPSO)算法进行了扩展.扩展粒子群算法(EPSO)提升了粒子自身认知能力和社会认知能力,增加了粒子共享的信息量,粒子在运动过程中更加智能化.4个新随机因子的引入,提高了种群的多样性,一定程度上克服了PSO容易陷入局部最优的缺陷,提高了PSO算法全局搜索能力.对6个常用目标函数进行优化仿真,结果表明EPSO算法较SPSO算法收敛速度显著加快,且不易陷入局部极值点.SPSO算法是EPSO算法的一种特殊情形;EPSO算法作为SPSO的扩展,可应用于所有SPSO求解的优化问题.     

基于CNBPSO算法的需求侧资源计划

为克服二进制粒子群优化(BPSO)算法易于陷入局部极值的不足,在粒子群算法(PSO)的速度更新公式中引入混沌参数与小生境机制,在此基础上提出了一种新的二进制粒子群(混沌小生境二进制粒子群优化,CNBPSO)算法.将新算法应用于两种不同复杂度的负荷削减需求计划问题的求解,均获得了比BPSO更好的中断方案,证实了算法的有效性,新算法具有简单、快速、均衡收敛等优点.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with