基于单神经元控制器的交流矢量控制系统

根据感应电机矢量控制原理，将单神经元控制器应用于磁场定向的矢量控制系统中，并给出了单神经元控制器模型，并将神经元控制器代替矢量控制系统中的转速调节器，进行了易于算法实现和实际控制系统实现的智能交流矢量控制系统设计和仿真研究，MAT－LAB仿真结果表明，该系统具有良好的动态性能。     

基于单神经元控制器的交流矢量控制系统

根据感应电机矢量控制原理 ,将单神经元控制器应用于磁场定向的矢量控制系统中 ,并给出了单神经元控制器模型 并将单神经元控制器代替矢量控制系统中的转速调节器 ,进行了易于算法实现和实际控制系统实现的智能交流矢量控制系统设计和仿真研究 ,MAT LAB仿真结果表明 ,该系统具有良好的动态性能     

两电机同步系统的神经网络控制

在对两台感应电机同步系统模型分析的基础上,依据同步系统的结构特点和控制要求,结合人工神经网络的非线性映射、自适应、自学习等能力,提出一种新的基于神经网络的两电机同步系统控制方案,其中神经网络控制器由基于RBF网络整定的自适应PID控制器和神经元解耦补偿器两部分组成.两个自适应PID控制器分别对速度控制回路和张力控制回路进行自适应控制,使系统具有更强的适应能力、更好的实时性和鲁棒性;神经元解耦补偿器综合两控制回路的耦合作用,通过训练网络权值,补偿各回路之间的耦合影响,实现速度和张力的解耦.试验结果表明:采用神经网络控制方法可以实现两电机同步系统中速度和张力的解耦控制,系统具有良好的动静态性能.     

卷绕张力控制器的三种设计方法及性能分析

给出了高速纺丝机卷绕张力控制器的三种设计方法:变参数PI控制、神经元自适应PID控制及神经元自适应PSD控制。对三种控制方法下系统的性能进行了对比,表明三种控制方法均具有较好的控制性能,其中神经元自适应PSD控制器设计简单,具有很强的自学习、自适应能力,是一种很好的张力控制方法。     

自适应神经元控制器在交流伺服系统中的应用

文章介绍了交流伺服系统的数学模型、组成及其原理,在此模型基础上对交流伺服系统的自学习控制进行了深入的研究;利用神经元的自学习功能实现神经元控制器的在线学习,并以神经元控制器作为交流伺服系统的位置调节器;仿真实验表明,神经元控制器与PID控制器相比具有较强的自适应性和较好的性能。     

神经智能PID控制算法应用

提出将 Ｐ Ｉ Ｄ 继电自整定与神经元自适应 Ｐ Ｉ Ｄ 控制相结合,利用 Ｐ Ｉ Ｄ 继电自整定法获取神经元自适应 Ｐ Ｉ Ｄ 控制器权系数的初值,实现对一般工业对象（一阶惯性加纯滞后环节）的智能控制．仿真和实时控制结果表明,这种控制策略是对实现全自动型工程控制器的有益尝试．该智能控制算法切实可行,鲁棒性强．     

一种神经元网络控制器及仿真

该文给了了一种自适应神经元的控制方法，设计了神经元网络作为控制器的智能控制系统，给出了学习规则，在交流伺服系统中的仿真结果表明了此方法的有效性及优越性。     

单神经元PID控制在锅炉水位控制中的应用研究

针对PID控制器的缺点,提出一种用于锅炉水位控制的单神经元自适应PID控制器。通过Simulink的仿真证明,该控制器利用神经元的学习特性,自动调节PID参数,控制效果优于传统PID控制。     

基于自适应PID控制器的异步电机矢量控制

为了克服传统PID控制器自适应性及鲁棒性相对较差的缺点。实现高性能的异步电机矢埴控制，提出了采用人工神经网络技术构造自适应PID控制器。在保证调速系统全局快速收敛的情况下，运用有监督的Delta学习规则和合理的控制算法。实现自适应PID控制器参数的在线自动调整。应用MATLAB软件设计基于自适应PID控制器的异步电机矢量控制模型并进行仿真研究，结果表明，自适应PID控制器不仅能够满足异步电动机矢量控制的实时性要求。而且可以大大改善异步电动机的动态性能与静态性能，表现出较强的自适应性与鲁棒性，因而可以取代传统PID控制器以实现高性能的异步电动机矢量控制。     

基于MATLAB的无速度传感器矢量控制仿真

设计了参数自调整模糊控制代替常规的PI调节器，构建无速度传感器异步机矢量控制系统，并运用Matlab＼Simulink工具构造异步电动机的矢量控制解藕数学模型、自适应神经网络速度辩识模型和参数自调整模糊控制器，对无速度传感器矢量控制系统进行了仿真．仿真结果表明：自适应神经网络速度辨识具有较高的辨识精度，且该系统具有良好动、静态性能．     

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.     

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.     

A computer generator for randomly layered structures

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

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.     

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the