Optimal Control of Semi-Active Suspensions with ER Shock Absorber

An ER shock absorber with mixed mode is designed and its mathematical model is built. The optimal control method with LQ is applied to semi-active suspension systems in vehicle. A optimal output tuner is designed on basis of 1/4 dynamic model and the characteristics of the ER shock absorber. Its aim function and the weighting parameter matrix are determined. The feedback gain vector is found from solving the Algebraic Equation. The result shows that the optimal controller could not only diminish the body acceleration effectively but also improve the ride and handling characteristics. The construction of the ER shock absorber is reasonable and its performance meets the optimal control requirements of semi-active suspension system under the 3 kV/mm. In additional, the optimal control has low cost and energy consumption as well as rapid response . Such a system can meet with the requirements of semi-active suspension control completely.     

Pole Normal Assignment for Linear Control Systems

The eigenvalues of a normal matrix are not sensitive to its elements perturbation. Based on the fact, the pole normal assignment problem for linear control systems is discussed. The aim is to find a state feedback control law. When the closed-loop system has desired poles and the closed-loop system matrix is a normal matrix, the robustness of the control system is enhanced. For linear constant systems, a necessary and sufficient condition is given to normal assignment of the desired poles. When the condition holds, a unified expression of the state feedback control laws is showed. An example is given for illustration of the proposed algorithm.     

Distribution Network Structure Planning Based on Improved Immune Genetic Algorithm

Distribution Network Structure planning is a complex combinatorial optimization problem,which is difficult to solve properly by using traditional optimization methods.In order to solve this problem,Improved Immune Genetic Algorithm is introduced to the distribution network optimal planning. Improved Immune Genetic Algorithm draws into the immune diversity and antibody's density mechanism to maintain the individual's diversity and remains evolution algorithm's global stochastic searching ability,so it can promote diversity and the whole optimal-searching ability of genetic algorithm.The optimal module takes the minimum annual cost as its object,and the capacity and voltage drop of feeder and the radiation of distribution network as its restrictions.According to the require of radiation of distribution network,the spanning tree of the alternative network is taken as the initial solution to speed up the calculation.And the branch-exchange method is used in designing crossover operator and mutation operator to avoid the radiation checking and enhance the optimizing ability.This algorithm has been illustrated effectively by examples,at the same time,the calculation example demonstrates that,the algorithm has higher calculation speed than the traditional immune genetic algorithm.     

Research on QoS Strategy of Web Server Cluster Application Based on Request Classification and Request Admission Control

The increase of requests often results in performance degradation of the web server cluster. The quality of service (QoS) expected by users can't be guaranteed. This is the problem that service-level web server cluster must cope with. In this paper, two strategies are proposed including classification of the user requests and request admission control, the different quality of service can be reached and the QoS of service-level users is guaranteed. The simulation experiments proved, the load balance of the system is improved and average response time of the system is decreased.     

Concurrent Optimal Design for the Mechanical Product Accuracy and its Mathematical Model

A new method,the concurrent optimal design for the mechanical product accuracy is addressed presented, this method is very suitable to a concurrent engineering context. Differing from the convensional tolerance design method, this method establishes a direct link between product working accuracy and machining precision of the parts. Therefore, in the product design phase,the optimal machining tolerances which satisfy the product working accuracy can be determined. Using this method, the design and manufacturing time and cost can be enormously reduced and product quality can be guaranteed.     

A HIERARCHICAL CONTROL METHOD FOR REACTIVE POWER OPTIMIZATION IN LARGE-SCALED INTERCONNECTED POWER SYSTEMS

This paper presents a new hierarchical and coordinative control method for reactive power optimization in large-scale interconnected power systems. It combines the interconnection forecast method for hierarchical control in large-scale steady state industrial systems with the incremental linear programming method for reactive power optimization in real time. The results of applying the method to power system examples show that the method not only solves the problem of high dimension in order, but also keeps the advantages of the incremental linear programming method. The proposed method is also suitable for the security analysis of reactive power correction in large-scale interconnected power systems.     

Information Structures in Portfolio Selection

This paper gives a brief presentation of the influence of different information structures on portfolio selection and some simple examples to demonstrate their basic algorithms. The first is the familiar mean_variance model. The model does not need more hypotheses on the motion of the asset price along the full continuous time axis,but sometimes many unanticipated computation problems may be involved because of the difficulty in computing the inverse of some matrices with high dimension. The second is the stochastic optimal control model. It is to solve a stochastic optimal control problem,which is often related to Hamilton_Jacobi_Bellman eqution.It results in solving partial differential equations of Riccati matrix differential equations. Their closed_form solutions are usually very hard to obtain. The last is the differential game model. The existence,uniqueness,and the computation for its equilibrium solution are all very difficult mathematical problems.     

Open motion control architecture of wind turbineand main controller design

In this paper, we propose a method to solve the problems with stochastic nonlinear and point to point architecture of the wind turbines. The proposed method presents an open motion control architecture and a linearized torque control system based on power curve LUT. We reference the PLCopen motion control standard that is used to design the linearized torque and pitch systems of the wind turbines. This proposes a new methodology for the main controller design and the system integration of wind turbines.     

Computer Aided Quality Control System of Steel-making Enterprise

In order to satisfy the quality of product's demand of consumer and improve quality while dropping expend, working procedure must be synthetically controlled because of product of steel-making is a continuous plant composed of many procedures. Logic and physics frame as well as subsystem's functions and interrelations including with quality schedule system, quality data collection system, quality evaluation and control system, quality information management system are analyzed based on CIMS of steel-making plant. At the same time computer aided quality control system of steel-making enterprise is designed and marked out. High grade and low cost products satisfied consumer are yielded by synthetically controlling every working procedure's quality, punctual consignment guaranteed.     

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.     

A Review of Recent Advances in Research and Development on Vehicle Semi-Active Suspension Systems

Based on the systems engineering theory, this paper reviews the trend of researches and developments on vehicle semiactive suspension systems, analyzes states of researches on electrorheological fluids and magnetorheological fluids material,and puts forward semi_active suspension sytems based on magnetorheological fluids damper. On the basis of summing up existing methods for vibration control on semi_active suspension systems, emphases are put on the discussion of aplication of PID control. linear optimal control,adaptive control and intelligent control on the semi_active suspension systems. The compound control strategy is put forward based on the skyhook damping control theory, fuzzy control theory and adaptive control theory. Moreover, the integral idea about the research and development of semi_active suspension is based on MR damper,and discusses some theories and applied problems deserving research.     

Research on a Risk Investment Portfolio with Stochastic Character

With the theory of stochastic differential equation, the authors discuss a problem of a class of risk investment portfolio with stochastic character. With the selection of appropriate utility function and combines the Hamilton-Jacobi-Bellman equation, under the assumption that an optimal portfolio exists, and by using the Homologous Lagrangian function, some quantitative results of this risk optimal investment portfolio are given. With these quantitative results, some qualitative results are got. These results concord with the results of the theory of risk investment.     

Analysis of Unified Power Flow Controller in Damping Low Frequency Oscillation of Power System

With the development and complication of power system, the problem of low frequency oscillation in electric network becomes obvious. Unified Power Flow Controller is one of the most powerful facilities in Flexible AC Transmission Systems, which can improve the transient stability and damp the low oscillation in power system with suitable control. Considering the characteristics of inverter's output voltage magnitude, adjustment of phase and process of charge and discharge of dc capacitance, the dynamic model of UPFC is proposed by a series of nonlinear differential coefficient equations. Based on UPFC's dynamic model, the linear optimal controller of UPFC with state feedback is proposed. In this way, the low frequency oscillation is damped effectively. A simulation is processed basing the theory.     

Analysis and Applicati on High- Efficacy Saving Energy Technique of Central Air - Conditioning System

Aimins at the state that present central air- conditioning systems performance in high ineffective energy consumption, this paper studies the reasons of ineffective energy consumption and the key technique to solove the problem. A set of energe saving device for central air - conditioning systems is developed. A system dynamical mathematical model is established in theory, and an optimal performance pattern is fired. The central air - conditioning system can work in the optimal pattern with effective comfortability and saving energy by using. The device may save power rate to 22.6% by survey and may have broad market prospect in the southern area.     

A DECOMPOSED OPTIMIZATION MODEL FOR POWER NETWORK PLANNING

This paper presents a decomposed optimization model for power network planning. The planning problem is divided into master problem to determine the investment decisions and subproblems to deterimne the operation decisions. In the proposed model, the effects of multi load levels,stochastic line outages,power loss cost and load curtailment cost on the investment decisions are considered. The results of the examples prove the feasibility and effectiveness of the proposed model.     

客家黄酒的品质保证

客家黄酒是中国黄酒的一个分支,也是广东省的传统特产。“绿纯”客家黄酒是广东著名品牌,通过绿色食品认证和ISO9000质量体系、H ACCP食品安全管理体系的建立,实现了对“绿纯”黄酒从“农田到餐桌”的全程质量控制,为产品品质提供了有力的保证。     

Research on Current Situation and Trend of Control Strategies for Hybrid Electric Vehicles

The vehicle's driving performances is determined by the control strategies and constructions of hybrid electric vehicles (HEV). The constructions of HEV are classified according to the change of state of charge of battery pack, and a study on current situation and trend of control strategies for HEV is presented in this paper. The research indicated that the current control strategies for HEV are not perfect and need further optimization. The control strategies should realize the optimum match among engine, motor, battery and transmission according to the characteristics of each component and vehicle's driving conditions. Many aspects including the fuel economy, emission, the life of battery pack, drivability, the reliability of each component and HEV's manufacture cost should be considered in the control strategies. A study on the control strategies and its optimization that take account of the aspects mentioned above is a work emphasis in the future. This paper also points out the PHEV equipped with small motor, small engine and continuously variable transmission is an ideal system construction for getting optimal fuel economy, lower emissions, steady drivability, lower manufacture cost and HEV's mass.     

Optimal allocation model and its genetic algorithms of outsourcingproduction resources in multi task

According to the characteristics of the outsourcing production such as multi task, dynamic environment, and multi objectives etc, an optimal allocation model of outsourcing in multi task is established by the linear weighted method. Outsourcing production time, outsourcing production cost and outsourcing production quality are set as its target functions. Then, genetic algorithm for solving this model is also investigated. Finally, a case study is employed for the effectiveness and the validity.     

Control strategy and parameters optimization outsourcing production inventory system under uncertainty

This paper proposes a control strategy for the optimal control of the outsourcing production inventory system based on production point and production batch. The statistical probability distribution is used to describe the uncertainty of the production capacity of cooperative enterprises and the transportation time. The optimization model of the control parameters is developed with random production capacity for cooperative enterprises and random transportation time in order to minimize the holding cost,setup cost as well as the cost of production capacity waste. A simulation-based control parameters optimization algorithm is designed to solve the proposed model. The control strategy of production inventory system and the control parameters optimization algorithm proposed are validated by an example. We analyze the influence of the variation of the production point and production batch to the performance of the outsourcing production inventory system.     

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.