基于现场总线的机器人和PC机之间通信与控制的实现

介绍柔性制造单元(FMC)中的通信方案，给出了基于现场总线(PROFIBUS)的机器人和PC机之间通信与控制的具体实现方法．利用ANYBUS-S现场总线从站模块XFB01成功地实现了MOTOMAN机器人与PROFIBUS总线的互连．     

PROFIBUS现场总线技术及发展分析

分析PROFIBUS现场总线发展现状,对PROFIBUS-DP现场总线技术的协议结构、通信原理、网络系统结构和设备分类等网络技术问题进行了阐述。将PROFIBUS与基金会现场总线FF、LONWORKS、控制局域网CAN及HART总线等几种目前已成熟的现场总线技术进行比较、分析,提出了PROFIBUS在应用中的几点优势。PROFIBUS与其他网络协议兼容形成开放的系统是PROFIBUS现场总线应用技术及网络的发展趋势。     

PROFIBUS非周期通讯技术在NT6000系统中的实现及应用

PROFIBUS是一种国际化、开放式、不依赖于设备生产商的现场总线标准.目前国产化主站有很多都实现了DPV0功能,但是没有实现DPV1非周期通讯功能.科远智慧经过多年的研究,在自研PROFIBUS协议栈的基础上进行开发,成功实现了PROFIBUS主站的二类非周期通讯功能(MSAC_C2).通过和上位机FDT/AMS软件的配合使用,现场总线主站可以将PROFIBUS DP/PA从站的周期/非周期数据采集到NT6000控制系统中,实现DCS和现场总线技术的完美结合.现场应用表明,非周期通讯模块技术先进,稳定可靠;可以很方便地管理现场PROFIBUS设备,满足客户需求.     

现场总线实验系统设计

本文采用PROFIBUS现场总线，设计完成了现场总线的实验秉统，该系统技术先进，为学生实验和教师科研的提供了良好的平台，实验系统具有良好的扩展性和兼容性。可以满足当前学生了解和掌握工业控制同络系统的架构，以及系统设计和调试的需求，提高了学生的动手能力。     

PROFIBUs现场总线在直线式拉丝机上的应用

本文通过对PROFIBUS现场总线的介绍，详细描述了PROFIBUS现场总线在直线式拉丝机上的应用。从生产的实际使用效果证明现场总线控制简单实用、稳定可靠，在金属制品设备中具有极大的推广价值。     

PROFIBUS——DP网在攀钢转炉提钒控制系统的应用

本文简要介绍现场总线的有关知识,以及PROFIBUS现场总线在攀钢转炉提钒基础自动化控制系统中的应用。     

PLC在工厂化学水处理监控系统的应用

本文介绍了电厂化学水处理系统自动化控制的实现。结合现场总线技术和工业以太网技术,信息层使用工业以太网,控制层使用PROFIBUS现场总线,完成了基于现场总线和工业以太网的自动化监控和管理功能。     

一种基于PROFIBUS的锅炉现场总线控制设计

锅炉作为工业生产的重要设备之一,实现其自动化控制是经济发展的必然趋势。本文提出了一套基于PROFIBUS的锅炉现场总线控制,该方案不仅包括了各种回路自动控制、数据自动采集、实验报表的自动生成设计,还包括了上位机操作站和现场控制单元的功能组态实现。     

基于PC-PLC网络的立体仓库自动作业监控系统的研究

以立体仓库自动作业系统为背景,重点对其监控系统进行研究,构建了基于PC-PLC网络的立体仓库自动作业监控系统,并模拟工业现场进行了调试。通过PROFIBUS现场总线将监控计算机、上位机PLC和下位机PLC连接成一有机整体;并应用工控组态软件WinCC对系统各组件进行硬件组态;采用PROFIBUS总线进行监控机、上位机和下位机之间的数据通信,实现了对立体仓库(AS/RS)自动作业的监控。现场调试证明,该监控系统界面友好,控制安全可靠,精度高,数据存储量大,数据传输正确,且功能多、使用方便简洁。     

基于PROFIBUS现场总线的远程监控系统的设计

随着计算机和信息技术的飞速发展,这些技术向工业控制网络领域渗透是必然的。PROFIBUS作为现场总线中协议最完善、应用最广泛、发展最迅速的总线之一,在现场控制领域应用已十分广泛。本文介绍了基于PROFIBUS现场总线的远程监控系统的设计方案。系统设计主要包括底层控制系统的设计;现场控制系统的设计;远程监控系统的设计以及各通信子层之间通信的实现方案。此外,文章对监控系统的主要软硬件选用及配置方法也做了介绍。     

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