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1.
In accordance with the present situation that there is a lack of deeper investigation of active vibration control of rigid flexible coupled structures with rotating rigid base,the significance of the buildup of experiment system is emphasized,and every component and its function of the experiment system is introduced in detail.The experimental setup has been finished so as to make rigid base rotate within some range at some different angular speed in the state of air bearing.  相似文献   

2.
The load changed of motor affects normal run. If it is not adjusted, the state of motor will become poor, while it affects steady of the system. This paper presents an efficient method for the motor speed controlling, it applies Tacagi-Sugeno's method that each linear submodels are connected for fuzzy algorithm, an algorithm of the fuzzy model identifying and fuzzy control is fulfilled through whole nonlinear model which are replaced with local linear models. It makes speed of motor to maintain steady, and variable structure control is applied to guarantee performance of dynamic flowing for process controlled, the design of stability and robustness is proposed in the scheme. Practice running results show that it is efficient that uncertain dynamic processes are controlled.  相似文献   

3.
The ratio control strategy and the relevant pulley clamping control strategy of the Metal Pushing V-belt Type CVT C Continuously Variable Transmission are key technology of CVT system matching. The engine output torque model and oil consumption model are given in numerical table by cubic spline interpolation to fit engine test result. Based on the engine speed feature, the speed ratio changing strategy of CVT in the numerical table are given to realize the optimal fuel economy and optimal performance mode within the ratio range of the CVT system.  相似文献   

4.
n this paper,researches of digital valves in Japan in recent years are briefly de-scribed. The operation principles and the structure of a new digital speed control valve are analysed.This new valve is made by Japanese Tokyokeiki company. Based on these investigations , theoretiealanalysis,degital simulation and experimental study are emphasized to the valve's static and dynamiccharacteristics.  相似文献   

5.
With rapid development of the civil\institutional\commercial central air conditioning system,the energy consumption problem becomes serious.From the view point of operation and management,this paper provides some measures to save energy through choosing suitable cooling and heating equipments,air handling units,terminal units or designing a better water system.  相似文献   

6.
果蔬食品的褐变与控制   总被引:9,自引:0,他引:9  
结合生产实际,对果蔬食品产生褐变的机理及其控制途径进行探讨。通过遗传学途径,培育果蔬新品种,使之不含易氧化变色物质,增强其天然抗褐变性,是控制果蔬褐变的根本途径。  相似文献   

7.
In the civil industry, quality is a key factor, so quality management and quality control play decisive roles in construction especially. At present, the main method of construction is quality controlling that engineers and technicians consult the standard and norm concerned, then check them one by one, and supervise the construction. It is not only inefficient but also easy to make mistake. Using computer technology in the quality control of construction will promote quality control level and improve management measures. Through the research of the quality control of construction,the system of quality control in construction is studied and developed, the structure of the software and its developed technology are expounded.  相似文献   

8.
张颖  程如岐  陈绍慧 《保鲜与加工》2021,21(12):111-117
果蔬分选是农业果蔬产后不可缺少的重要环节,以可编程逻辑控制技术为核心的自动化生产线为现代农业的智能化发展提供了新途径.为提高果蔬的分选效率,减少本地分选的人工成本,将数据采集、数据处理、无线通讯、智能控制等技术深度融合,研究一种可远程控制的果蔬智能分选机制,并通过可编程逻辑控制器(PLC)自动化数据采集与机械控制和.NET Core架构的分布式网络控制方法两方面对远程控制分选方案进行研究,配合合适的糖度-质量等果蔬品质模型,实现高速远程在线果蔬智能分选.基于该分选技术的软硬件方案进行试验,对控制策略和分选精确度进行仿真.结果表明,与传统的果蔬分选技术相比,该系统从系统成本、反应速度、分拣精度、管理效率等方面均有优势,果蔬分选精度能达93%以上,可以实现远程故障排查,节省了人工成本,具有推广应用价值.  相似文献   

9.
综述了微生物在我国畜产品质量安全中存在的问题,以及提高畜产品质量和安全性的微生物控制措施,建议对食源性病原微生物污染进行监控,并加强各领域的国际合作研究。  相似文献   

10.
This paper discusses how to design and implement a security subsystem, which based on the Role-based Access Control technology. By taking a teaching web system as a practical example, the paper establishes an access control matrix, so dynamic menu, page jump, and data access control are loaded. The experimental shows that, the system can controls the access authorized data, and to avoid the illegality access. The practicability and robust in the system is evident.  相似文献   

11.
The computer monitor and control system for hydropower station is always a structure system of laminate distribution and open style. The system can adjudge active power and inactive power of water turbine according to the requirement. The operators in active-control level give the value of active power and inactive power for water turbine by computer workstation. PLC of LCU run the power control procedure by net communication in order to realize power adjust. The power adjust of water turbine mainly by speed control system and magnetization system. The 2-D Fuzzy PID Control Model is proposed in order to carry out power adjust of water turbine . In this new method the parameter of PID can self-neaten on line according to power deviation and power deviation rate. By means of this procedure the machine unit can obtain given power value rapidly, exactly and stably. It can make the power adjust of monitor and control system obtain good control characteristic and robust, and it is benefit to extend the work life of machine unit.  相似文献   

12.
According to the quality of one-time ,uncertainty and high risk in engineering project, the importance of management by objetctive of construction project is expatiated. The features and structure model of the system of management by objects are analyzed and established. The principle to determine the superiority of objectives in different levels and the "Analytic Hierachy Process" to calculate the weight factors are put forward. The method of active and passive control is employed to manage the project dynamically so that the successful enforcement of the overall objectives will be ensured and meanwhile the best investment effect will be achieved.  相似文献   

13.
为解决乳制品的质量安全控制问题,将HACCP体系与质量功能展开(QFD)相结合,应用HACCP体系进行全过程控制,运用QFD获取乳制品质量安全控制的顾客需求项及各项权重,根据各项关键控制指标的重要度,完成预防措施质量屋的构建并应用到HACCP体系预防措施和纠偏措施的制定中,从而对乳制品质量安全进行控制。  相似文献   

14.
A new idea "Pretreatment and cycle stream of control" and the scheme to put it into practice is presented. In space region,the circuit is designed to form chain and cycle,and in time region,the program is designed to distinguish the period and the instant.It is ensured that the pretreatment will be finished in the period and there is always a circuit to wait to the triggered at the instant. So the respond speed of the system is almost approximate to that one of trigger circuit.  相似文献   

15.
Industrial Personal Computer(IPC) system generally works in long duration,and so a stable software is essential for an IPC system.Linux has a good deal advantages,such as,stability in use,open source code and free of charge, therefore an IPC measurement and control system has developed based on Linux. Multi-task scheduling is the critical part in system software.A simple method to realize multi-task scheduling in IPC measurement and control system based on Linux alarm clock mechanism is presented. Linux alarm clock mechanism is implemented by the cooperation of software timers and system call that is used to install and handle alarm clock.First, Linux process timers,soft interrupt signals, relevant system call are introduced,as well as applications of Linux alarm clock mechanism in multi-task scheduling. And then an example of the application in the IPC measurement and control system is given. The system has passed longtime run test,accomplished expected functions and shown well stability, so that practicability of the scheduling method has been authenticated.  相似文献   

16.
果蔬产品变色原因分析及其控制   总被引:4,自引:0,他引:4  
分析了果蔬产品在加工贮存中变色的原因,综述了目前生产中常用的行之有效的护色措施,包括生物、化学和物理等方面的处理方法。  相似文献   

17.
本文综述了国内外现代果蔬物流运输保鲜环境调控系统发展现状,包括温度、湿度、气体和压力四大调控系统,并对今后我国物流运输保鲜发展提出了展望。  相似文献   

18.
管宏友 《中国农学通报》2022,38(26):133-138
为客观分析土壤污染防治的研究进展、研究热点和研究趋势,利用文献计量学方法,回溯了2000—2019年土壤污染防治研究的演化轨迹。通过对研究前沿和热点的追踪,揭示了中国土壤污染防治研究热点的动态变化和发展趋势。结果显示:中国土壤污染防治已受到学术界的广泛关注;土壤污染防治研究领域中学科差别较大;土壤污染防治的关键词较为分散。  相似文献   

19.
矮化密植苹果园病虫害综合防治技术研究   总被引:3,自引:0,他引:3  
通过对河南省矮化密植苹果园优势病虫种类、主要天敌种类、主要病虫发生危害规律、覆草园天敌种群变化的系统调查研究,通过设置频振诱虫灯诱虫试验,高效、低毒、低残留化学农药及生物源农药筛选试验,制订出了适用于矮化密植苹果园的病虫害综合防治配套技术。实施该项技术后,病虫危害降低3倍以上,果品经检测无农药残留,经济、生态、社会效益显著。  相似文献   

20.
20%高渗毒死蜱乳油防治棉花棉铃虫田间药效试验初报   总被引:2,自引:1,他引:1  
20%高渗毒死蜱乳油在二代棉铃虫发生盛期防治,每公顷施用有效成分270g时药后1、3和7d的矫正防效分别达83.99%、89.08%和89.73%,速效性和持久性均显著优于12%路路通乳油每公顷施用量1800ml效果(67.63%、74.61%、76.54%)。从保顶效果看,20%高渗毒死蜱乳油每公顷施用有效成分270g时为89.30%,显著优于对照12%路路通乳油1800ml每公顷施用效果80.70%。  相似文献   

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