基于现场总线的铣削加工过程自适应模糊控制

在分析Profibus总线和模糊控制特点的基础上,针对铣削加工过程的非线性、时变性和不确定性,提出了基于现场总线的铣削加工过程自适应模糊控制的解决方案．采用输出比例因子和控制规则在线自调整的方法对切削参数变化的铣削力进行在线控制．仿真结果表明,该方案克服了传统的模糊控制动态响应较慢和鲁棒性较差的缺点,具有响应速度快、实时性和稳定性好等特点．当切削深度突变时,能在线自适应调整进给速度。使切削力接近参考值,实现恒力切削,防止刀具损坏和提高加工效率．     

加工过程的不确定性信息度量

加工过程存在着模型不确定性、参数不确定性和测量不确定性等不确定性信息。这些不确定性信息或是随机性的、或是模糊性的、或是复合不确定性，可分别用概率熵、模糊熵和混合熵来度量。研究加工过程的不确定性信息及其测度，对研究基于信息优化的加工过程智能控制有重要意义。     

基于串级变结构神经网络的机器人补偿控制

针对机器人动力学的非线性、强耦合、时变特点,为了高速、高精度地控制机器人,提出了基于神经网络的机器人智能控制策略．讨论了机器人动力学模型的特殊性,指出模型中结构和非结构不确定性因素;研究了一种新型串级变结构神经网络（ＣＶＳＮＮ）;提出了一种基于新型ＣＶＳＮＮ的机器人控制策略．以精密Ｉ号机器人为仿真对象,证明该算法能够较好地补偿结构与非结构不确定因素,收敛速度快,能够自适应地调节自身的结构．     

智能控制及其在机器人领域的应用

从认识论和方法论的角度、学科交叉、控制对象、系统设计、知识获取等方面分析了智能控制与传统控制的区别。指出智能控制的优势是具有开放的、分级的、分布式的结构，有较强的综合信息处理能力，善于处理模型具有不确定性、高度非线性、复杂的控制任务。它的不足是理论基础还处在发展阶段，控制精度不高，实时性较差。提出了智能控制今后的发展应当是多种智能控制方法集成和智能控制与传统控制结合的思想。     

非线性不确定系统的鲁棒拟人控制器设计

尽管拟人智能控制方法自提出以来取得了很多成功应用，但在系统存在不确定性的情况下，如何基于拟人智能控制方法设计系统的鲁棒控制器一直是个难题．针对仿射非线性不确定系统，结合二级倒立摆系统作为设计实例，提出了一种鲁棒拟人智能控制器设计方法．首先，基于被控对象的标称模型设计拟人控制律；然后在采用拟人控制律的基础上，应用积分滑模控制方案设计鲁棒补偿器，用以抑制模型不确定性对系统稳定的不利影响、提高系统的鲁棒性．最后，对二级倒立摆控制系统进行了仿真和实验验证，仿真和实验结果进一步证明了设计方案的有效性．     

基于PCA—SVM模型的切削颤振预报

针对切削加工过程中颤振孕育的动态模式,提出一种基于PcA—SVM模型的颤振预报新方法。建立切削加工振动信号的识别模型,进行FFT变换,再归一化处理,把数据送人PCA—SVM模型,对变换后的切削实验数据进行学习、训练,得到PcA—sVM识别模型;提取切削加工过程的振动信号,送给PcA—sVM模型进行颤振情况分析与识别。试验结果表明,具有较好的颤振预测性,颤振预报正确率达到95．5％以上,提高了运算速度,为颤振预报提供了充足的时间。     

浅谈自适应智能控制系统

智能控制是近年来在控制领域中出现的新动向，它不完全依赖于被控对象的数学模型．自适应控制，能够适应较大范围系统和环境的不确定性以及信息的模糊性，为复杂系统的控制开辟了新的途径，因而这种控制方法受到控制界的广泛重视，也被广泛应用于实际的工业过程控制中，并且取得了较好的控制效果．     

航空铝合金加工时的变形控制

随着目前飞机制造业的大力发展,对于航空铝合金的加工工艺要求也越来越高,而航空铝合金在加工时的变形问题也成为了航空制造加工过程中出现的重要问题之一。为了解决这一问题,我国从国外引入了先进的高速切削设备,并开始自主研究高速切削加工技术。根据大量地研究表明,选择合理的加工参数、控制切削中的残余应力和对加工零件恰当使用可以大大地提高航空铝合金高速切削的质量。     

工-夹系统刚度计算及变形加工误差模型

研究切削加工过程中工件-夹具系统的刚度计算方法及变形加工误差.运用经典Hertz接触理论和有限元方法,基于切削加工中工件的准静态受力分析,提出工件-夹具系统刚度计算的新方法,建立了基于工件-夹具系统刚度的工件加工误差预报模型.该方法避免了有限元计算中接触分析的使用,无需多次非线性迭代计算,减少了计算时间.     

智能过程控制的应用

研究智能过程控制的应用问题，即智能过程自动化问题。文中分若干个领域讨论了智能过程控制的应用，给出典型系统的原理结构框图。这些应用领域包括智能过程监控、自动加工过程智能控制，生产过程的智能故障检测与诊断、飞行器飞行与降落过程的智能控制和医疗过程智能控制等。     

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.     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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