最优Fuzzy-GA PID控制器及其应用

提出了一种基于模糊推理与遗传算法的最优PID控制器的设计方法 .该控制器由离线和在线 2部分组成 .在离线部分 ,以系统响应的超调量、上升时间及调整时间为性能指标 ,利用遗传算法搜索出一组最优的PID参数K p ,T i 及T d ,作为在线部分调节的初始值 ;在在线部分 ,采用一个专用的PID参数优化程序 ,以离线部分获得的K p ,T i 及T d 为基础 ,根据系统当前的误差e和误差变化率 e ,通过模糊推理在线调整系统瞬态响应的PID参数 ,以确保系统的响应具有最优的动态和稳态性能 .计算机仿真结果表明 ,与传统的PID控制器相比 ,这种最优PID控制器具有良好的控制性能和鲁棒性能 ,可用于控制不同的对象和过程     

风力发电机组最佳功率追踪自适应模糊PID控制

针对变速恒频风力发电系统,以额定风速以下风能的最大利用率为目标,设计了基于自适应模糊PID控制的风能最佳利用追踪控制器.该控制器对叶尖速比进行控制,运行时根据实际输出的叶尖速比与其最优值间的误差及误差变化率在线实时调整PID参数,实现自整定,达到风能利用系数最佳的功率追踪目标.通过仿真对几种控制方法进行对比分析,结果表明,自适应模糊PID控制能够将风能利用系数和叶尖速比均控制在最优值附近,系统的稳态性能和动态性能都较好,控制效果优于PID控制和模糊控制.     

基于蚁群算法的智能人工腿最优PID控制器设计

以蚁群系统和蚁群算法为基础,提出了一种新的具有不完全微分的最优PID控制器的设计方法.该控制器以系统单位阶跃响应的超调量σ、上升时间tc以及调整时间ts为性能指标,针对给定的控制对象,利用所建立的蚁群算法搜索出一组最优PID参数K*p,*i及T*d,作为实时控制中PID控制器的参数.该控制器被用于控制智能仿生人工腿中的执行电机.计算机仿真结果表明,与传统的PID控制器相比,这种基于蚁群算法的最优PID控制器具有良好的动态和稳态性能,可用于控制多种不同的对象和过程.     

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.     

一种基于满意度的PID参数整定方法

提出了一种基于满意度与遗传算法的PID(Proportional Integral Derivative)参数在线整定控制器的设计方法．利用满意解的原理设计系统响应超调量、上升时间及调整时间等的满意度函数，再离线通过遗传算法搜索PID控制器的3个参数kp，ki和kd作为在线调整PID参数的基值，然后设计跟踪误差与kp，ki和kd的关系函数，在线调整PID控制器参数，以获得良好的稳态性能、动态性能及鲁棒性能．Matlab仿真结果证明了所提出的PID控制器的有效性。     

一种参数在线自调整模糊控制系统

介绍了一种参数在线自调整模糊控制系统的设计方法。该系统采用参数调整器在线调整传统模糊控制器的量化因子和比例因子以达到调整系统性能的目的。积分环节的加入进一步提高了系统的稳态精度。     

带前馈的模糊积分控制器在伺服系统中的应用

以数控机床的伺服控制系统为对象，提出了带前馈的参数自整定模糊积分控制模式，在设计伺服控制器时将积分引入模糊控制器，以减小控制死区，提高稳态性能；同时引入前馈，以进一步提高响应的快速性和减小动态响应的误差。仿真结果表明了该方法在斜坡响应中无超调，稳态精度高。     

自调整模糊控制器在异步电机矢量控制系统中的应用

针对异步电机矢量控制系统因电机参数变化和负载波动等因素性能变差的问题 ,设计了一种二维自调整模糊控制器作为滑差频率式异步电机矢量控制系统的速度调节器。这种自调整模糊控制器可以根据输入变量的大小调整模糊控制器的量化因子、比例因子和两个输入变量的权重 ,从而自动调整模糊控制规则。仿真和实验结果说明 ,具有自调整模糊控制器的异步电机矢量控制系统不仅动态和稳态性能都得到提高 ,而且具有较强的鲁棒性。     

基于论域自调整模糊规则切换的双模控制器

 针对系统的初始响应,设计了一个兼顾快速性和稳定性的论域自调整的模糊控制器,并用线性PID控制器来实现稳态时的高精度控制,2个控制器之间采用模糊规则进行切换.并给出了它的动态性能、抗干扰能力及鲁棒性的实验结果.     

基于遗传算法的无人机模糊-积分控制器设计

针对某小型固定翼无人机纵向姿态控制和轨迹跟踪的要求设计了一种模糊-积分混合控制器. 为避免控制器参数调试的复杂性,提高控制性能,利用遗传算法对模糊控制的隶属度函数进行了优化设计. 在优化设计阶段,确定了设计变量和约束条件,并给出了比例因子整定原则. 仿真结果表明,基于遗传算法的模糊-积分控制器与传统PID控制器相比具有更短的响应时间,鲁棒性强,并且解决了单一模糊控制器稳态响应精度低、响应曲线颤振的问题.      

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.     

A computer generator for randomly layered structures

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

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。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

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

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.     

Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application

Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.