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1.
基于组态王和PLC的电梯控制系统设计 总被引：1，自引：0，他引：1
李胜多 《青岛农业大学学报(自然科学版)》2010,27(2):168-171,175
本文利用组态王和PLC实现了对某电梯的控制,详细说明了其硬件系统的组成及软件设计的思路,利用组态王对电梯控制进行人机界面设计,实现了对该电梯的动态监控的功能。该电梯运行可靠、稳定,实际运行情况良好。 相似文献
2.
Maitri Thakur Bobby J. MartensCharles R. Hurburgh 《Computers and Electronics in Agriculture》2011,75(2):327-336
Data management in food supply chains to facilitate product traceability has gained importance in recent years. This paper presents a relational database model to facilitate internal traceability at a grain elevator, which is one of the first nodes in a food supply chain. This approach for modeling traceability information in bulk food supply chains has not been studied in past. At an elevator, grain lots (inbound deliveries) are blended to meet buyer specifications, and individual lot identity is not maintained. As a result, an outbound shipment to a customer likely contains grain from many different sources. In a food safety related emergency, tracing the source of a problem or tracking other affected shipments would be nearly impossible. An efficient internal data management system could mitigate these problems by recording all grain lot transformations/activities, including movement, aggregation, segregation, and destruction as well as supplier and customer information. In this paper, a relational database management system is proposed that stores all necessary information, including product and quality information, related to the grain lots in order to enable product traceability. The system can be queried to retrieve information related to incoming, internal and outgoing lots and to retrieve information that connects the individual incoming grain lots to an outgoing shipment. Furthermore, this system can be used both to trace back to the source of a given lot and to track information about previously shipped lots forward. In addition to traceability application, the information stored in this database provides a comprehensive dataset for many applications including mass flow optimization, resource optimization and improved operational efficiency of the grain elevator. 相似文献
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We report the incrementally staged design, synthesis, characterization, and operation of a molecular machine that behaves like a nanoscale elevator. The operation of this device, which is made of a platformlike component interlocked with a trifurcated riglike component and is only 3.5 nanometers by 2.5 nanometers in size, relies on the integration of several structural and functional molecular subunits. This molecular elevator is considerably more complex and better organized than previously reported artificial molecular machines. It exhibits a clear-cut on-off reversible behavior, and it could develop forces up to around 200 piconewtons. 相似文献
4.
东洋电梯门机控制系统的技术改造 总被引：1，自引：0，他引：1
杨世凤 《中国农业大学学报》1996,1(2):104-108
针对东洋电梯故障多，运行质量差的现状，提出了用可编程逻辑控制器对门机主控系统和调速模式进行技术改造的方案，进行了该系统的硬件研制和软件设计工作。试运转结果表明，该系统设计合理，逻辑控制准确可靠，开关门速度模式明显到改善，门约红外光电检测保护系统动作及时可靠，保障乘客进出门户的安全。改造后电梯门机的工作性能达到和超过了原东洋电梯的理想工况。 相似文献
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本设计以开发一个电梯模拟系统为目标。首先,设计了电梯调度算法,并画出了系统流程图;其次,在设计过程中使用双缓冲技术来解决电梯图片在刷新过程中出现的闪烁现象;最后,给出了模拟电梯功能测试图。通过对本系统的研究与实现,得到了如何运用计算机技术模拟植物生长的启发。 相似文献
6.
本文介绍了电梯理想速度曲线的数学模糊，根据工程实际进行了曲线参数的优化，用Ｔｕｒｂｏ Ｃ语言编制计算程序成功地求取了电梯运行速度按距离控制所需的Ｖ＝ｆ（ｓ）曲线，仿真结果表明，各项技术指标均满足要求，为电梯速度的实时控制准备了必要的条件。 相似文献
7.
液压电梯控制系统的仿真与实验 总被引：2，自引：0，他引：2
由于液压电梯电液流量控制系统是一典型的非线性、变负载、变液容和变粘度的工程控制系统，它的性能直接影响到液压电梯系统的舒适性。为了研究电液流量控制系统的运行特性，本文建立了液压电梯系统的参数数学模型，并转化为相应的计算机模型，对它的运行特性进行了仿真和实验研究，分析比较了在流量反馈和速率反馈两种控制方式下液压系统的运行特性。 相似文献
8.
由于液压电梯电液流量控制系统是一典型的非线性、变负载、变液容和变粘度的工程控制系统，它的性能直接影响到液压电梯系统的舒适性。为了研究电液流量控制系统的运行特性，本文建立了液压电梯系统的参数数学模型，并转化为相应的计算机模型，对它的运行特性进行了仿真和实验研究，分析比较了在流量反馈和速率反馈两种控制方式下液压系统的运行特性。 相似文献
9.
电梯故障时,具有故障特征提取困难和故障类型识别率低的问题。因此,拟提取其振动信号并进行分析,找到故障特征。然而,鉴于其振动信号为非平稳、非高斯且背景噪声较大的信号,给有效辨识造成很大困难,所以,提出应用最优小波包分解和最小二乘支持向量机相结合进行电梯智能故障诊断的方法。借助最优小波包理论,首先提取电梯故障振动信号的能量分布;然后将其能量分布与时域指标相结合,构造故障特征向量;最后,将故障特征向量作为粒子群算法优化最小二乘支持向量机的输入对电梯故障类型进行识别。仿真结果表明,最优小波包理论与最小二乘支持向量机相结合的故障诊断技术发挥了两者的优势,证明了该方法的有效性和实用性。 相似文献
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BAS是采用计算机及其网络技术、自动控制技术和通信技术组成的高度自动化的建筑物设备综合管理系统。本文结合地下车站BAS系统配置图介绍了南京地铁一号线BAS系统的系统结构,系统对通风系统、照明系统、给排水系统、导向标识系统、电梯、自动扶梯的监控功能,BAS系统工程软件及系统运行的特点。 相似文献
12.
One of the main goals of the Russian agro-industrial complex is striving to achieve world indices. To achieve this, the fundamentals of the Russian grain economy have been revised; elevator farming and forage production are brought to the modern level. Russian production of grain-forage has been improved: the content of food grains in it is reducing and the content of barley, leguminous, and corn is increasing. These lead to cropping increasing of the mentioned crops. As a substitution for soy protein, protein of lupine and peas are offered. This protein is almost equal in quality to soy protein but is much cheaper. Further investigations on the cattle physiology will help to reveal the genetic potential of calves and cows. 相似文献
13.
链杆式升运器薯土分离损伤机理研究 总被引：1，自引：0，他引：1
4GS-1500型甘薯收获机采用链杆式升运器作为输送分离装置,是杆条升运链式甘薯收获机的典型代表机具。为改进链杆式升运器设计、减小输送分离和抛薯过程中对甘薯的损伤,以商薯19、阜薯24、郑薯20为对象,采用配置了链杆式升运器的4GS-1500型甘薯收获机进行甘薯收获试验,运用力学、运动学等原理,结合试验分析,研究链杆式升运器在输送分离、抛薯过程中产生损伤的原因和减小损伤率的措施。结果表明:配置了链杆式升运器的4GS-1500型甘薯收获机主要损伤形式为表面擦伤,同时伴有压损、薯肉缺损、断裂等特征。损伤主要由输送分离时土块、甘薯、链杆等对甘薯挤压、冲击、摩擦以及抛薯时甘薯撞击地面所产生的冲击造成。通过优化链杆式升运器的设计参数和运行参数,甘薯损伤率降至约1.5%。 相似文献
14.
本文在介绍组态软件与PLC构建工业控制系统基础上,着重介绍了组态王与FX2N系列PLC构建的电梯控制仿真系统,介绍了组态王65图形界面设计、数据库建立、动画连接、及组态软件与PLC间的通信格式设置,该控制仿真系统可以实现上位PC对实际电梯控制系统运行的实时监控,也可以在脱离实际物理的控制对象情况下,实现对控制程序的调试和仿真运行。 相似文献
15.
A model is developed to describe the flow of grain through a clean grain elevator system on a combine in order to facilitate
accurate mass flow rate estimation. The relationship between mass flow rate and impact force described by the model depends
upon machine operational characteristics, mechanical interactions of the grain and the machine geometry, and material properties
of the grain. The model was designed to be adaptable to varying grain conditions, such as those influenced by moisture content,
by allowing free parameters of the model to be estimated through a nonlinear regression algorithm. Simulations were performed
using discrete element modeling software and data was obtained from experiments conducted on a clean grain elevator system
at the University of Kentucky Combine Yield Monitor Test Facility to determine the ability of the model to accurately estimate
mass flow rate. The model estimated mass flow rate with a normalized root mean squared residual (NRMSR) less than 2% for discrete
element modeling simulations. For experiments involving machine components, NRMSR values were less than 3% for corn at 14%
moisture, less than 3% for corn at 21% moisture, and less than 5% for corn at 26% moisture. 相似文献
16.
作者根据当前消火栓给水系统设计中室内消火栓的位置,消防电梯前室的消火栓是否计入总数,防火分区间的消火栓是否可以借用,消火栓给水系统消防水泵的控制,消火栓给水系统的减压、分区原则等易出现争议的问题,提出了自己的观点,供大家研讨。 相似文献
17.
针对4M-2马铃薯联合收获机的功能要求,通过理论分析确定了其传动方案、抖动升运系统、茎杆分离系统及倾斜式输送系统的主要参数,该系统结构紧凑,传动效率高,功率消耗低,能保证抖动升运链、茎秆分离器、横向输送器和侧向倾斜式输送器等部件协调工作,可一次性完成薯块的分离、输送、装箱作业,提高收获效率. 相似文献
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蒋兆阳 《安徽农业大学学报》2003,(3):25-27,30
中国加WTO以后，中资银行普遍开办了个人理财业务，这对中资银行积极参与国际竞争将起到积极作用。但在实践中，中资银行的个人理财业务发展还不够理想，必须通过中
外资银行在此项业务领域中的优劣势比较，在目标市场、功能、竞争策略方而进行准确定位，再通过各种手段加以发展，才能将中资银行的此项业务推进到一个更高的水平。 相似文献
20.
分析了农地承包经营权收益权缺失的主要表现,体现在现行立法在农地征收中未对农地承包经营权设立单独的补偿项目;在征地补偿中缺乏对农地承包经营权预期收益和间接收益损失的补偿;对流转权利的不合理限制妨碍了农地承包经营权流转收益的实现。提出了完善农地承包经营权收益权的对策：应当在农地征收中设立农地承包经营权单独补偿项目;在征收补偿中包括对农地承包经营权预期收益和间接收益损失的补偿;取消对农地承包经营权流转权利的不合理限制。 相似文献