A PRIMARY STUDY ON A LIFTING PERFORMANCE CURVE ADAPTED FOR THE MECHANICAL LOAD MOMENT LIMITER

The condition when forces are applied to load mechnical mornent limiter of tow-er cranes is analysed and disctissed in this paper.A lifting performance curve adapted for the me-chanical load moment limiter is also obtained.And finally,the curve drawing method is explainedthrough the practical example.     

A SENSITIVITY METHOD FOR THE WEIGHTING MATRIX SELECTION OF LINEAR OPTIMAL CONTROL

The paper analyses the relations between closed-loop system dynamic qualities and linear optimal control weighting matrix Q and offers a sensitivity method for selecting weighting matrix Q. As a practical example, a linear optimal supplement excitation control system is designed for a single machine-infinite bus power system using the presented method. Theoretical . analysis and simulation results have shown that the dynamic qulities of the control system are very satisfactory.     

ENERGY-SAVING AND OPTIMAL HIERARCHICAL CONTROL OF WATER PLANT

In this paper, on condition that the production processes in water plant are related with each other, a new coordinative algorithm is presented, using a hierarchical control structure and taking the equivalent efficiency of the pump station as coordinative variable. In this way, the problem of optimal control of the complex delay system is solved. Simulation shows that great energy-saving efficiency may be obtained by the above method.     

ON THE PROBLEM OF SWITCHING CONDITIONS FOR A KIND OF MINIMUM-TIME CONTROL SYSTEMS

The paper provides a detailed study of switching conditions of minimum-time control systems based on application in engineering. By analysis in theory and experiment, the authors deduce a set of switching conditions with state and control variabes inequality constraints, the variations of system parameters and the time-delay of computer in real time control. As an example, a DC motor speed control system is considered. By digital simulation and physical experiments,these conditions proved to be correct. The method in this paper is also suitable for other control systems using compound control algorithm.     

PAYING ATTENTION TO USE SIMPLEX METHOD FOR OPTIMAL MULTIPARAMETER IN THE DESIGN OF CONTROL SYSTEM

In the design of control system using simplex method for optimal multi-parameter,if the difference in number between the greatest and the smallestparameters is very great,the optimization process converges very slowly.Evenoptimal parameters can't be found at all.This paper studies the problem,analyses its cause and poses a resolution means.A testing example shows thatthis means can solve the above problem well.     

OPTIMAL CONTROL OF REACTIVE POWER AND VOLTAGE BY FICTITIOUS VARIABLES METHOD

A method introducing fictious variables for resolving the linear model of reactive power and voltages control in power systems is presented. The method theoritically guarantees the resolvability and optimizition of linear programming model. This method has been proved successful by IEEE 6 -node test system and the several practical power systems such as 49-node, 155 -node systems.     

THE APPLICATION OF NETWORK PROGRAMMING METHOD ON THE SHORT TERM OPTIMAL SCHEDULING FOR CASCADED HYDROPOWER STATIONS

The problem of the short term economic scheduling for cascaded hydropower stations is discussed with the network programming method. A new network model is built to dispatch the load to each unit when the unit commitment is determined. An algorithm of the minimal cost maximal flow is also discussed using the model and the algorithm to the Longxi River Cascaded Hydropower Stations, the computational result on the microcomputer VAX II shows that the model and the algorithm are correct and applicable.     

A NEW COMPENSATIVE SNUBBER FOR ELIMINATING THE SURGE AND NOISE IN PWM CONVERTERS

A new compensative snubber is presented for eliminating the surge current and high frequency parasitic oscillation in rectified circuit of the PWM DC-DC converters. The output surge and noise voltages are de-creased over 4/5. The working principle of the sunbber is analyesd in detail, the designing formulas are derived. The theoretic analysis is consistent with the experimental results.     

OPTIMAL SELECTION ON THE INTERVALS FOR HANDLIND THE RHYSICAL EXPERIMENT DATA BY THE METHOD OF DIFFERENCE WITH DATUM BY DATUM

This paper discusses the mechanism and reason for decreasing the handling polynomial function data on difference with durum by datum.From the error theory,some exemples are analysed and the equivalent principle for the intervals on datum by datum is presented.The optimal number for intervals is analysed in detail and shown by some examples for the correct result.At last,by making comparison between some methods for handling the physical experimental data to show the advantages of them,the proper condition and range in use for every method is also presented.     

A FICTITIOUS CONTROL METHOD FOR OPTIMIZATION OF APPROXIMATE PERIOD PROCESS

The main problem in optimal control of approximate period process is the optimization of periodic initial state. A fictitious control method is advanced in this paper. In combination with the link method of states between two periods, this method not only gives a quite good optimal result, but also reduces the quantity to be computed and stored. The simulation of optimal control in a water plant shows the availability of this method.     

THE DECENTRALIZED LOAD FREGUENCY CONTROL FOR MULTI-AREA POWER SYSTEMS

A decoupled load-frequency control model of a multi-area interconnecting power system is presented and a practical and effective decentralized control method is developed, which needs only its own state information and the information measured in it. It can also improve the stability and dynamic characters of the system. The dynamic simulation of the numerical example of a three-area interconnecting system with this controller showes the dynamic characters are almost the same as the centralized full state feedback optimal control.     

THE OPTIMAL DESIGN AND ENGINEERING APPLICATION OF DISTRIBUTION

This paper introduces the metod of optimal design of municipal water distribution,The main points are the theory,mathematical model,program frame figure and example in practice of the optimal method of hydraulics.The program is applicable to the design and calculation of the pipe network in a city. It gives a simple and convenient calculation method for multiple-scheme design and scheme cmparison of water supply system.     

储粮病虫综合防治

在储藏产品保护中，化学防治是一项必需的防治技术，由于害虫对药剂抗性的发展以及药剂残毒和对环境的影响等因素，降低了化学防治的作用，有必要进一步研究改进，并通过分析经济损害水平和经济阈值模式来合理实施化学防治。综合防治或有害生物综合治理是储藏物保护的一个方向，在实践中，已有采用各项措施协调配合防治储藏物病虫的经验，值得进一步总结，更好地贯彻“以防为主、综合防治”的储粮保扩方针。     

THE OPTIMAL DECISTON OF ECONOMICAL DEVELOPMENT BY MARKOVIAN DECISION PROGRAMMING

This paper studies the tactics choice and its improvement in the development of economy by means of Markovian Decision Programming. An optimal decision and the maximum expected revenue can be obtained. The . paper also presents the procedures and formulas of numerical evaluation.     

PREDICTIVE INTELLIGENT CONTROL OF THE COLD STORAGE

The predictive intelligent control scheme is proposed, which is based on approximation theory and numerical method of Chcbyshev orthogonal polynomial. It has the practical value to the cold storge using widely electromagnetic valve and can be also applied similar systems in orther area.     

THE ELECTRIC CONTROL TECHNIQUE OF THE HYDRAULIC LOGIC VALVE

This paper presen ts the electric con trol devive of the hydraulic logic valve.Itcontrains mainly two parts, a push button control and a microrocomputer wireless telecontrol.Thedesign and adjustment of the hardware and the software program are also presented.The results ofthe experments to the hydraulic system of the loader show that the device has the features of smallvolume,excellent performance,low cost and easy to develop software.     

THE APPLICABILITY OF OVERLAPPING DECOMPOSITION DECENTRALIZED CONTROL

The overlapping decomposition decentralized control is a kind of static feedback control system. Using overlapping information sets among subsystems, the reliability of the control system is improved. On the other hand the overlapping decomposition decentralized control systom isn't suitable for all systems waiting control. As for some systems, using overlapping decomposition decentralized control doesn't reach the desired control effect. This paper has discussed the applicability of the overlapping decomposition decentralized control offers the necessary conditions for applying this control technique, and provides theoretical basis for the wide applications of the overlapping decomposition decentralized control systems.     

粮仓窗户远程自动控制系统设计

设计出一种粮仓窗户远程自动控制系统。根据仓内外的温度和湿度变化,自动开启或关闭窗户及通风机械,实现粮仓的自动通风,自动控制。该系统可与粮情检测系统、通风控制系统等结合,组成粮仓自动化管理系统。     

FAST ADAPTIVE FILTERING ( FAF ) FOR THE PROCESS DETECTION CONTROL SYSTEMS

The limitation of LMS adaptive noise cancelling (ANC ) is analyzed here. Based on the discussing of general signal and noise model of process detection control system, a fast adaptive filtering(FAF) is proposed on the basis of modelling the correlativity between the noise and it's correlative noise with the view of large noise. Fast transversal filtering ( FTF ) adaptive, algorithms is used to imitate the correlative modelling. Both simulation and experiments show that the method presented in this paper is suitable for the process detection control system , and it exhibts better results than the LMS noise cancelling method.