基于2-D理论的时滞离散系统的开闭环迭代学习控制方法

针对一类具有状态时滞的线性系统,提出一种基于2-D离散系统的开闭环迭代学习控制器．给出控制器的收敛条件并给出了证明．该控制器既保持了以往开闭环迭代学习控制算法的优点,又减少了其收敛条件所受的限制．仿真结果验证了该控制算法的有效性．     

具有死区的饱和工业过程控制系统的迭代学习控制

对具有死区的非光滑饱和工业过程的稳态优化进程施加迭代学习控制,给出加权开环PD型迭代学习控制算法。算法基于前次迭代的输出动态信息和事先给定的理想轨张,修正工业过程控制系统的阶跃输入,以期改善控制系统的动态品质。给出了理想轨线的选取方法,提出了理想轨线的δ可达性和迭代学习算法的ε收敛性的概念。利用Bellman-Gronwall不等式和λ范数理论,论证了算法的ε收敛性。数字仿真表明,迭代学习控制能有效改善工业过程稳态优化进程中控制系统的动态品质,如减少超调,加快动态响应速度,缩短过渡时间等,显示了算法对工业过程控制系统的有效性。     

运动控制系统自学习问题研究

研究了运动控制系统在重复运动方式下的自学习问题,设计了开环迭代自学习、闭环迭代自学习和预测自学习三种控制算法和结构,并对比分析了各种自学习控制算法的特点。实验结果表明,学习控制结构简单,计算量小,便于实现,对被控对象的动态模型没有严格的要求,可以明显改善具有周期性输入控制系统的轨迹跟踪精度。     

初态偏移非线性系统跟踪控制的迭代学习算法

基于迭代学习控制理论提出一种新的可变增益学习控制算法,并对系统初态的迭代学习律进行了讨论,利用算子理论证明在非线性系统中存在初态偏移时经过迭代学习后,输出仍能跟踪期望轨迹;对其收敛性进行数学证明,得到谱半径形式的迭代学习律收敛的充分条件,从而解决了可变学习增益迭代学习控制的初态偏移问题.最后在注塑机注射速度控制系统中与增益不可变迭代学习算法进行比较,仿真结果验证了算法的有效性.     

滞后控制系统的一种新型控制算法

在Ｄａｈｌｉｎ算法和改进的Ｓｍｉｔｈ补偿控制算法的基础上．对滞后控制系统数字调节器的设计提出一种新的控制算法．计算机仿真表明该控制算法得到比较满意的控制效果．     

一种误差修正鲁棒广义预测控制算法

本文为模型补偿方法提高预测精度，提出了一种新的便于实时计算的广义预测控制算法，理论分析及仿真表明．该算法可以克服建模误差的影响．增强控制系统的鲁棒性．     

均热炉温度神经网络迭代学习控制算法

针对具有不确定性的重复非线性均热炉温度控制系统,提出基于神经网络的迭代学习控制算法,该算法采用神经网络作为迭代学习控制器,以前馈方式作用于被控系统,并引入PID反馈控制器来提高系统的性能.仿真结果表明,针对过程存在的重复干扰,该算法比单纯反馈控制具有更好的控制效果.     

一种新的迭代学习控制快速算法

对一类连续系统的迭代学习控制问题进行了讨论，提出了一种新的迭代学习控制算法，该算法与目前的算法具有完全不同的形式，数值仿真结果表明了新算法的有效性与优越性。     

分数阶线性系统初值学习的PDα型迭代学习控制

针对分数阶线性时不变系统的随机初值问题,提出了基于初值学习的PDα型分数阶迭代学习控制算法,利用λ-范数,对控制算法的收敛条件进行了严格证明,并利用仿真实验进行验证.理论分析和仿真实验表明,系统初值不论如何取值,在该算法作用下,随着迭代次数的增加,都能实现系统输出对期望输出的精确跟踪.相比传统的PDα型控制算法,该算法解决了传统控制算法要求系统初值与期望初值相同的限制,消除了随机初值对系统的影响.     

控制时滞系统的遗忘因子迭代学习算法研究

提出遗忘因子是关于迭代次数的函数,简化了传统遗忘因子迭代学习控制算法的收敛条件,并给出了收敛性分析.将改进收敛条件的遗忘因子迭代学习控制算法应用于一类带控制时滞的线性系统,给出了仿真实例.仿真结果表明,在改进的收敛条件下,合理地选择遗忘因子函数,带遗忘因子的PD型迭代学习控制算法在研究的控制时滞线性系统应用之下具有一定的有效性和优越性.     

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.     

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

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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