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1.
针对生产备料车间人工拾取火焰切割板材过程中劳动强度大、效率低下等问题,开发了一套板材下料自动拾取机器人系统。该机器人系统采用三坐标龙门式结构,利用伺服电机驱动三坐标直线导轨模组;上位工控机利用C语言和Matlab编程分别实现G代码向图形与坐标的转化与板材重心坐标值的计算,通过OPC Server与下位机PLC S7-300进行通信,将切割后的各板材重心坐标值通信至下位机PLC;PLC根据重心坐标位置控制三坐标伺服电机的运动,可保证拾取过程的平稳,减小晃动,实现对板材的连续精确拾取。该机器人控制系统是一种高度自动化的系统,可提高企业生产效率,适应于现代企业的生产要求。  相似文献   

2.
吴文芳 《现代教育技术》2009,19(Z1):298-299
在PLC课程教学中,运用PLC编程控制器,可实现对三相异步电动机的Y—△启动和正反转控制。基于这一控制原理,对三相异步电动机的星形—三角形启动正反转PLC控制器的设计目的、工作原理、制作要求和注意事项作简要阐述。  相似文献   

3.
介绍了使用三菱FX2N可编程控制器编写的1个3层电梯的控制系统。利用亚控组态软件组态王6.0制作人机对话界面,检验电梯PLC控制系统的运行情况。实践证明,可编程控制器(PLC)和亚控组态软件结合有利于PLC控制系统的设计、检测。  相似文献   

4.
应用三菱FX0N可编程控制器编写的一个三层电梯的控制系统,利用MCGS组态软件制作人机对话界面,检验电梯PLC控制系统的运行情况。实践证明,PLC可编程控制器和MCGS组态软件结合有利于PLC控制系统的设计、检测,具有良好的应用价值。  相似文献   

5.
文章首先对智能制造系统以及可编程控制器的基本知识作了简单的介绍,然后提出在制造过程中的智能监视和控制系统中应用PLC控制器,最后证明应用PLC控制器对其进行智能监视和控制具有巨大的优势和发展前景。  相似文献   

6.
PLC是可编程逻辑控制器的简称。本文以PLC在机械手控制中的应用为例,介绍PLC的应用原理以及使用方法。  相似文献   

7.
论述了基于西门子S7系列PLC可编程控制器的网络控制实验系统的构建思路,实验室的建设改变了传统的以分散的PLC可编程控制器为基础的实验模式,符合现代自动化系统“集中管理、分散控制”分布式网络化控制系统发展趋势。介绍了该PLC网络实验系统的总体结构,说明了各部分设备配置的选型分析,阐明了实验项目的设计思路。通过实验教学实践证明,PLC网络实验系统将PLC的网络技术、通讯技术、控制技术整合在一起,是学生学习并掌握PLC应用技术的良好平台。  相似文献   

8.
介绍了可编程逻辑控制器PLC的应用现状,对PLC在开关量的逻辑控制、模拟量控制、运动控制、数据处理、通信及联网等多个方面的应用现状进行综述。通过总结PLC技术的发展前景,指出建立新型PLC教学实验体系势在必行。  相似文献   

9.
可编程序控制器(Programmable Logic Controller简称PLC),在工业生产过程自动控制领域得到广泛的应用,而可编程序控制器的实际应用,需要符号要求的系统设计。探讨系统采用PLC控制的一般本条件和系统设计的基本原则,能很好地寻求PLC最适合的控制对象。基于系统设计内容与步骤的分析,有助于结合实际问题进行PLC控制系统的设计。  相似文献   

10.
本文简要介绍了可编程序控制器(PLC)的特点和应用范围,PLC控制系统设计的一般原则和步骤,以及PLC的发展趋势  相似文献   

11.
The experiment in which a candle is burned inside an inverted vessel partially immersed in water has a history of more than 2,200 years, but even nowadays it is common that students and teachers relate the change in volume of the enclosed air to its oxygen content. Contrary to what many people think, Lavoisier concluded that any change in volume in this experiment is negligible; moreover, the explanation relating oxygen consumption in the air with its change in volume is known to be wrong. In this work we briefly review the history behind the candle experiment and its relationship with some typical erroneous explanations. One of the key factors behind Lavoisier’s success was the use of experiments carefully designed to test different hypotheses. Following these steps, we performed several closed volume experiments where the candle wick was replaced by a capillary stainless steel cylinder supported and heated by a nichrome filament connected to an external power supply. Our recorded experiments are displayed as web pages, designed with the purpose that the reader can easily visualize and analyze modern versions of Lavoisier’s experiments. These experiments clearly show an initial phase of complete combustion, followed by a phase of incomplete combustion with elemental carbon or soot rising to the top of the vessel, and a final phase where the hot artificial wick only evaporates a white steam of wax that cannot ignite because no oxygen is left in the closed atmosphere. After either a complete or incomplete combustion of the oxygen, our experiments show that the final gas volume is nearly equal to the initial air volume.  相似文献   

12.
天保房地产开发公司根植于天津滨海新区。依托控股公司带来的资源优势,基于滨海新区列入国家发展战略部署的背景,在近年来取得了迅速的发展。但是随着国家一系列政策的出台,中国的房地产行业面临着一次大的重新洗牌过程,同时企业内部仍然存在着制度缺陷、管理不规范、流程不清晰、人员激励不足等各方面的问题,所以,天保房地产公司在面临着滨海新区良好发展机遇的同时,也面临着很大的挑战。如何在机遇与挑战并存的环境中,认真分析和评估企业的外部环境及内部资源与能力的优劣势,对企业内部的资源与能力进行积累与培养,制定相应的竞争与发展战略,引导企业的健康长远发展具有一定的必要性与迫切性。 本文从竞争战略的角度,综合分析天保房地产开发公司所面临的外部环境和内部条件,研究探讨天保房地产开发公司的发展战略框架,包括战略的指导思想、战略定位、战略目标及相应的实施措施,以期实现天保房地产开发公司的发展愿景和核心价值。  相似文献   

13.
指鹿为马     
秦二世时,丞相赵高野心勃勃,日夜盘算着要篡夺皇位。可朝中大臣有多少人能听他摆布,有多少人反对他,他心中没底。于是,他想了一个办法,准备试一试自己的威信,同时也可以摸清敢于反对他的人。  相似文献   

14.
Easy Phonics带你学习自然拼读,让你学会字母的发音规律,正确地拼读单词。本期让我们继续来看看、读读、写写重读音节中包含字母a的单词,区分它们读短音short a-/e/,还是长音long a-/ei/。  相似文献   

15.
Easy Phonics栏目带你轻松地学习自然拼读!在读读、听听、拼拼和玩游戏中,你将了解字母的发音规律,并正确地拼读单词。这一期,我们来学习元音字母a的短音(short a)和长音(long a).  相似文献   

16.
从前,有一句话,叫做"吃得苦中苦,方为人上人".这句话被认为动机不纯,怎么可以做"人上人"呢?其实,对于"人上人"可以作不同的理解,一种理解是"骑在人民头上,作威作福",这种"人上人"当然不好;但也可以解释为比别人做更多的贡献,吃更多的苦,经过更多的挫折与困难而比一般人更成熟、更坚强,更知道怎么做人.实际上,对这句话应是作后一种理解的,因为这种"人上人"是与"苦中苦"联系在一起的.  相似文献   

17.
本文从毕飞宇小说中一再出现的镜、钟、影和胡琴的意向入手,考察毕飞宇小说的叙述人称、叙述速度、叙述结构和叙述意图。深入阐释"我"与"他"的分离与揉合,"快"与"慢"的交替与演变,"是"与"非"的分明与模糊,"语言"与"沉默"的相反而相成。  相似文献   

18.
The concept of metacognition refers to one’s knowledge and control of one’s own cognitive system. However, despite being widely used, this concept is confusing because of several reasons. First, sometimes it is not at all clear what is cognitive and what is metacognitive. Second, researchers often use the same term, namely, “metacognition” even when they refer to very different aspects of this complex concept. Alternatively, researchers may use different terms to indicate the same metacognitive elements. Another foggy matter is the interrelationships among the various components of metacognition discussed in the literature. This conceptual confusion regarding the concept of metacognition and its sub-components calls for in-depth theoretical and conceptual clarifications. The goal of this article is to portray a detailed example of a conceptual analysis of meta-strategic knowledge (MSK) which is one specific component of metacognition. This specific example is used to draw a general model for conceptual analyses of additional metacognitive components. The approach suggested here is to begin with a clear definition of the target sub component of metacognition, followed by a systematic examination of this sub component according to several dimensions that are relevant to metacognition in general and to that sub component in particular. The examination should include an analysis of how the details of the definition of the target sub-component refer to: (a) general theoretical metacognitive issues raised by prominent scholars; (b) definitions formulated and issues raised by other researchers who have investigated the same (or a similar) sub-component and, (c) empirical findings pertaining to that sub-component. Finally, it should be noted that since metacognition is a relational rather than a definite concept it is important to situate the context within which the conceptual analysis takes place.  相似文献   

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