基于MPC的三容水箱液位跟踪控制的快速实现

针对三容水箱系统大时滞、动态响应慢问题,研究了三容水箱系统的液位跟踪控制。采用模型预测控制策略,设计了三容水箱的液位跟踪控制器,并通过FPGA加以实现。控制器硬件和软件系统采用基于NiosⅡ嵌入式软核处理器的FPGA/SOPC方案,在基于FPGA和dSPACE的平台上,进行了实时联合仿真。实验结果表明,基于FPGA的模型预测控制器能够实现对三容水箱系统的液位跟踪控制。该实验可应用于自动控制、过程控制等相关课程教学,方便高效,具有较好的实验演示效果。     

基于实验的三容水箱数学模型

三容水箱液位控制系统实验装置模拟了工业生产过程中对液位、流量参数的测量和控制。它具有过程控制中动态过程的一般特点：大惯性、大时延、非线性,难以对其进行精确控制。在实验的基础上对三容水箱的数学模型进行推导并在Simulink上进行仿真。仿真和实验结果显示建立的数学模型正确的反映出了三容水箱的动态特性。     

三容水箱液位控制系统建模与仿真

介绍了微型三容水箱系统设计原理,通过机理建模法及系统特性建立了分段二阶单输入单输出模型。运用PID液位控制算法,并使用Simulink对实验模型进行了仿真,通过组态监控软件对建模结果进行了验证。仿真与实验结果表明,实验模型可以正确反映三容水箱的特性。可为工业应用以及高校教学科研提供控制算法研究的实验平台。     

三容水箱液位控制系统的间歇故障检测实验教学设计

基于MATLAB软件和TTS20三容水箱系统,设计了闭环控制策略下的三容水箱泄漏故障检测实验。实验模拟三容水箱系统运行过程中可能出现的间歇泄漏故障,利用龙伯格观测器和滑动时间窗口,设计截断式残差以检测间歇故障的发生时刻与消失时刻。文章给出了具体实验步骤,实验结果验证了该实验教学设计的可行性与有效性。该实验有助于学生了解故障检测技术的前沿知识,提高科研工作热情。     

三水箱多变量液位控制实验设计

三容水箱液位控制实验系统是一种非线性、强耦合、多变量和大滞后的复杂系统。该文首先介绍三容水箱液位控制实验系统的实物系统装置,然后设计了几种典型的多变量液位控制实验,并给出了被控对象的数学模型,最后对上述系统被控对象的能控性和能观性进行了分析。     

基于TCP-IP网络和实时数据库的三容水箱远程控制系统

为了适应过程控制中的复杂系统控制和特殊环境远程控制的要求，作者利用TCP-IP网络和实时数据库技术的新发展所带来的便利，在原有的三容水箱系统上开发了网络控制、实时数据采集、传输、处理和视频直播等功能，实现了网络虚拟实验；同时通过互联网实现了三容水箱系统的相关控制功能，为过程控制教学实验提供了很好的网络平台。这套系统已经投入到清华大学过程控制的教学科研中，相关的功能正在不断扩展。     

远程实验数据监控系统设计与应用

为改变传统实验开放度和智能化程度不高的情况,自主研制了三容水箱实验平台,设计了远程数据监控系统。该系统通过三容水箱数据中继器将数据采集器实时采集的数据上传至数据监控软件处理,数据监控软件运用多线程技术实现数据存储、数据显示并发送控制指令,对远程实验台进行故障检测、智能管理和实时监测控制,为开放式远程控制实验创造条件。     

基于S7-200 PLC的过程控制实验平台开发

提出了过程控制实验平台设计理念和思路,开发了过程控制实验平台,分为硬件设计和软件设计两部分。以西门子S7-200PLC为控制器,三容水箱为被控对象,构建对象柜和操控台等硬件系统,开发基于STEP7-Micro/WIN的实验项目程序,设计基于MCGS工控组态软件的实验平台监控界面,通过实时通信实现对典型生产工艺过程的监控。该实验平台可开展过程控制类相关实验,提高学生创新实验技能和综合应用能力。     

基于Matlab GUI的三容水箱液位实时监控系统设计

为了实现三容水箱教学实验平台中液位控制算法的多样化和可移植性,设计了基于Matlab图形用户界面(Graphic User Interface,GUI)的计算机监控系统。利用Matlab的串口通信API,通过RS-485/RS-232数据通信接口实现对三容水箱液位的数据采集和控制。通信采用Modbus RTU协议确保数据的可靠传输。系统软件界面友好、编程方便、操作简单,同时用户可以植入算法使系统运行于多种模式下。结果表明,基于Matlab GUI设计的计算机监控系统能够快速、准确地绘制出液位响应曲线,Flash动画能够实时模拟出实验进度。     

基于LabVIEW的过程控制实验平台开发

基于LabVIEW开发了A3000的实验平台,以进行虚拟仿真控制和实时通信控制实验教学。建立了A3000水箱系统的机理模型,完成了调节阀、变频泵和水箱特性等重要参数的测量和辨识,建成流量调节阀单回路控制、双容串级控制、下水箱前馈反馈控制、比值控制和扩展范围的分程控制等5个控制仿真实验平台。平台采用模块化设计,通过OPC server与实际A3000装置进行通信,实现了实时控制。     

Western and Eastern culture differences in commercial field

The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.     

汉字倒说

汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。     

风的曲线

Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.     

团图为数的图中的闭团贯数

Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F.     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

Social and Cultural Influence on Word Meaning

Different nations have different social cultures, and the social culture of every nation is developing with the development of the nation, language is greatly influenced by social culture, which enables language to possess national and historical characteristics. Word is the smallest, independent, meaningful linguistic unit of language. It can well reflect the national and historical characteristics. From synchronic aspect, the social and cultural influence on word meaning is mainly embodied in conceptual and associative meanings of word. The incorrespondence of word meaning is a phenomenon that exists in both conceptual and associative meanings of word among different languages. From diachronic aspect, the development of social culture causes some changes of word meaning to some extent. Therefore, social culture plays a key role in vocabulary learning and mastery of a language.     

钱生钱!

我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了     

Inequalities for inscribed simplexes

The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex.