模糊PID控制在液位控制系统中的应用

提出一种基于模糊规则的PID控制器的设计方法.该方法以建立模糊规则和进行模糊推理来调整PID控制器的kp,ki,kd等参数,通过JX-300X集散控制系统对QXLPC-Ⅲ液位对象进行控制.实验结果表明,所设计的模糊PID控制系统比常规PID控制系统具有更优良的控制品质.     

多级思维进化寻优的模糊PID控制器设计

为了提高模糊PID控制器的适应性，首先对模糊PID控制器进行简化处理，简化后的PID被控参数与量化因子、比例因子和解析规则相结合，构成多参数寻优的模糊PID控制器，同时采用多级“思维进化算法“对参数进行分组分阶段交替寻优，以适应各种环境的变化。仿真结果表明，MEA—模糊PID控制系统的结构合理，解决了模糊控制中参数优化问题，取得了良好的控制效果；同时在保证控制效果的情况下，大大简化了模糊PID控制器的设计。     

一类基于PID控制的新型模糊控制方法

研究了一类基于模糊规则的变参数 PID控制方法 .对于模型未知对象 ,常规 PID控制器参数的调节一般要基于一些语言信息的经验知识 ,这对 PID参数的调节带来一定的困难 .模糊控制在处理语言信息方面具有一定的优势 ,因此将模糊控制和 PID控制方法相结合组成一种复合控制器的设计是可行的 .采用 TS模糊模型 ,给出了一类给予模糊规则的变参数 PID控制器的设计 .这种控制方法兼备模糊控制与 PID控制优点 ,具有广泛的应用价值     

磁悬浮系统的模糊PID控制器设计

基于GML1001磁悬浮实验装置设计了一个模糊PID控制器.该控制器利用传统的PID控制器和模糊控制器相结合形成,能根据系统偏差的大小、方向以及变化趋势等特征,依据模糊规则库做出模糊推理,能自动调整PID参数,可达到更加满意的控制效果.利用设计的模糊自适应PID控制器,对磁悬浮控制系统中钢球的悬浮位置实现了精确的控制.实验结果表明,模糊自适应PID控制器可以使磁悬浮控制系统拥有较好的稳态和动态性能.     

模糊免疫参数自整定PID控制系统设计及仿真

为了提高模糊PID控制器的控制性能,将模糊参数自整定与免疫进化算法相结合,设计了一种模糊免疫参数自整定PID控制系统。该控制系统首先利用模糊规则,在线调整控制系统的kp,ki,kd,利用免疫机理修正非线性函数f,然后利用免疫修正环节进一步调整PID控制系统的参数。数字仿真结果表明,新的模糊免疫参数自整定PID控制系统具有稳定性好、响应速度快等特点,具有很高的应用价值。     

基于自适应Fuzzy-PID控制的变截面板簧AGC控制系统

以PID控制作为调节系统的主要手段,提出了将模糊控制和PID控制结合起来应用于变截面板簧轧制控制系统的方法,构成了一个参数自整定的模糊PID控制器.通过模糊规则在线调解PID的各项参数,达到了改善系统性能的目的.Matlab仿真实验结果表明:控制系统的响应曲线性能较好,响应速度较快,超调量小,稳态精度高.     

模糊PID控制在水位控制中的应用与仿真

水位控制系统具有非线性、非最小相位、时滞和强耦合,难以建立精确的数学模型。本文在分析常规PID控制器局限性的基础上,运用模糊逻辑,借鉴三冲量控制方法,将模糊规则整定PID参数的控制方法引入锅炉水位控制中,设计出一种模糊PID控制器,对PID三个参数在线整定。仿真研究和在实验室的实际应用表明,模糊PID控制器特性比常规PID控制器更优良,能有效地改善控制效果。     

基于模糊PID的变频水泵恒压供水系统仿真

针对中央空调机组的恒压供水问题提出了一种基于模糊PID控制器在线调整PID参数的变频水泵恒压供水系统.讨论了如何确定模糊PID控制器的隶属函数和模糊规则的问题,利用MATLAB软件中的模糊控制工具箱和Simulink对系统进行了仿真实验,并对常规PID控制器和模糊PID控制器分别选取了两组不同的系统传递函数,模糊PID控制器通过输出调整量ΔKp、ΔKi、ΔKd,对PID的参数Kp、Ki、Kd进行了在线调整.仿真实验结果表明模糊PID控制器不仅能有效抑制超调现象,提高系统的响应速度和稳态性能,而且对系统结构参数变化的适应能力也更强.     

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．     

运动控制系统的PID参数模糊自整定

讨论了模糊自适应PID控制器原理及参数的模糊调整,利用模糊推理方法实现对运动控制系统的PID参数在线自整定,并在Matlab/Simulink环境下将该控制器在运动控制中的应用进行了仿真.结果表明,参数自适应模糊PID控制能使运动控制系统达到满意的效果.     

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.