基于灰色预测的自适应内模PID双重控制器设计

针对一类非线性系统，提出一种基于灰色预测的自适应内模PID双重控制方法．把由系统的输入输出数据得到的灰色预测模型作为系统的内部模型，并在基本的内模控制结构上增加PID控制器，加快了跟踪误差收敛速度，内模控制的性能明显改善．仿真结果表明，该控制方法简单而有效，内模PID双重控制较单一内模控制具有更好的系统性能．     

改进灰色预测模糊PID控制策略

针对过程工业对气动调节阀的控制精度与稳定性有较高要求,而常规PID控制策略自适应性与实时性差,难以取得较好的控制效果的问题,根据GM(1,1)模型灰色作用量具有的动态特征来改进灰色预测模型,结合改进灰色预测控制与模糊PID控制的优点,提出了改进灰色预测模糊PID控制策略.仿真结果表明:改进控制策略明显优于常规PID、模糊PID、灰色预测模糊PID控制策略,使系统响应速度加快,超调量减小,且适用于不同的阀门定位系统.     

基于状态预测的无人机导航控制

基于飞行惯性对无人机路径导航实时控制和控制精度的影响,将灰色预测模型与模糊PID控制进行融合,提出了基于无人机飞行状态预测的导航控制策略.将无人机飞行状态预测信息作为系统状态调节的输入,构建灰色预测模糊PID航向控制系统,达到对无人机进行实时、准确导航飞行控制的目的.仿真实验结果表明:灰色预测模糊PID控制器可以有效提高无人机导航控制系统的鲁棒性、实时性,与传统的PID控制器相比,其控制性能更优.     

灰色预测模糊自调节PID控制器及其仿真

结合灰色预测、模糊自调节与传统PID控制的设计思想,提出灰色预测模糊自调节PID控制算法.该算法用系统输出误差和系统输出预测误差合成的综合误差作为PID控制器的输入,同时模糊自调节系统又能根据综合误差及其变化率来调整PID参数.仿真结果表明,与模糊自调节PID控制器相比,该控制器具有良好的动态性能和鲁棒性.     

基于改进灰色预测模型的自适应PID控制算法

针对大滞后系统提出一种基于改进灰色预测模型的自适应PID控制,采用优化背景值和初始条件的改进GM(1,1)模型作为预测模型,用预测结果代替被控对象测量值,克服了大滞后系统控制效果不能及时反馈的不足,并将二次型性能指标引入到PID控制器的整定过程中,按照性能指标的负梯度方向修改加权系数,实现了自适应PID的最优控制。仿真结果证明,该方法对大滞后系统具有较好的适应性和鲁棒性。     

基于灰色理论PID控制的伺服转台研究

针对伺服转台系统带有未建模特性的实际情况,以及传统PID控制无法满足高精度伺服转台的指标,利用灰色理论对未知信息数据的处理能力,对不确定量建立了灰色模型,实时补偿系统的未建模特性和干扰信号,提高控制精度．仿真显示应用灰色理论PID控制的伺服转台系统,控制精度明显改善,同时适应了工程控制的实际需要．     

模糊PID控制在汽车ABS中的应用与仿真研究

ABS是一种变工况、非线性的系统，参数自整定模糊PID控制可以利用模糊控制规则对PID参数进行在线修改，因而具有较好的自适应能力．设计了一种参数自整定模糊PID控制器，在分析单轮汽车模型的基础上，探讨了其在汽车ABS上的应用．采用模糊控制、PID控制、模糊PID控制三种方法分别对汽车ABS进行仿真研究，结果表明：模糊PID控制方法兼备了前面两种方法的优点，可以达到更好的控制效果．     

主动式升沉补偿控制系统及运动预报

针对主动式升沉补偿系统的时滞特性会造成控制效果变差甚至使系统失稳问题,考虑采用模型预测控制算法对其进行控制.并从提高系统抗干扰性角度出发,将模糊-比例积分微分(PID)控制与模型预测控制进行结合形成预测模糊PID控制,并将其与动态矩阵PID控制进行了仿真比较.最后为了进行实时的升沉补偿,采用时间序列法自回归预测模型对吊装点的运动进行了预报.仿真结果表明:预测模糊PID控制在系统存在时滞的情况下既保证了系统的稳定性又提高了系统的抗干扰性;时间序列法自回归预测模型对于极短期的运动预报具有较高的预测精度,可以满足主动式升沉补偿系统的预报要求.     

灰色组合预测模型应用研究

道路交通事故预测是道路交通安全研究的一项重要内容,它的目的是为了掌握交通事故的未来发展状况,对交通安全措施的可行性和实施效果进行合理评价,有效地控制各影响因素,达到减少交通事故的目的．可构建适应道路交通系统多属性特点的道路交通事故预测模型：灰色预测及其改进模型、神经网络预测模型、灰色神经网络组合预测模型．实证结果表明,灰色组合预测模型能够充分发挥各单一模型的优点,同时弱化了单一模型的缺点,比单一模型的预测结果更理想,精度更高．     

步长自调整的预测模糊控制器的研究

在介绍灰色模型(GM)建模的基础上,把预测控制的思想引入到模糊控制器中。模糊控制器的两个输入变量为设定值,与灰色预测模型的输出值之间比较得到预测误差及其预测误差的变化率。并根据过程状态提出了一种预测步长自调整的模糊决策机制,进一步改善系统的控制性能,即把由模糊决策器得到的预测步长作为灰色预测模型的一个输入来控制。仿真结果表明,该方法具有良好的控制性能和实用价值。     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

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.     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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