Computational Engineering Commons^™

Discrete-Time Hypersonic Flight Control Based On Extreme Learning Machine, Bin Xu

Bin Xu

This paper describes the neural controller design for the longitudinal dynamics of a generic hypersonic flight vehicle (HFV). The dynamics are transformed into the strict-feedback form. Considering the uncertainty, the neural controller is constructed based on the single-hidden layer feedforward network (SLFN). The hidden node parameters are modified using extreme learning machine (ELM) by assigning random values. Instead of using online sequential learning algorithm (OSLA), the output weight is updated based on the Lyapunov synthesis approach to guarantee the stability of closed-loop system. By estimating the bound of output weight vector, a novel back-stepping design is presented where less online …

A Human Proximity Operations System Test Case Validation Approach, Justin Huber, Jeremy Straub

Jeremy Straub

A Human Proximity Operations System (HPOS) poses numerous risks in a real world environment. These risks range from mundane tasks such as avoiding walls and fixed obstacles to the critical need to keep people and processes safe in the context of the HPOS’s situation-specific decision making. Validating the performance of an HPOS, which must operate in a real-world environment, is an ill posed problem due to the complexity that is introduced by erratic (non-computer) actors. In order to prove the HPOS’s usefulness, test cases must be generated to simulate possible actions of these actors, so the HPOS can be shown …

Comparing Qos Of Dsdv And Aodv Routing Protocols In Vehicular Network, Aref Hassanpour, Hooman Hoodeh, Amirhossein Zarrinnegar, Arsalan Emami, Rafidah Md Noor

Hooman Hoodeh

With the advance of Vehicular ad-hoc network, routing protocol has become one of the most important issues in transmitting data among Vehicles. The two routing protocol are DSDV and AODV which DSDV is known as a novel approach in proactive system; however, AODV has good performance in reactive system. In this paper, we compare the efficiency between DSDV & AODV in terms of packet-loss, end-to-end delay and throughput based on given scenarios. The comparison has implemented in various speeds for acquiring result with higher performance. The speeds consist of 5, 20 and 40km/s. then we analyze the explicit results according …

Adaptive Kriging Controller Design For Hypersonic Flight Vehicle Via Back-Stepping, Bin Xu

Bin Xu

No abstract provided.

Direct Neural Discrete Control Of Hypersonic Flight Vehicle, Bin Xu

Bin Xu

No abstract provided.

Adaptive Discrete-Time Controller Design With Neural Network For Hypersonic Flight Vehicle Via Back-Stepping, Bin Xu

Bin Xu

In this article, the adaptive neural controller in discrete time is investigated for the longitudinal dynamics of a generic hypersonic flight vehicle. The dynamics are decomposed into the altitude subsystem and the velocity subsystem. The altitude subsystem is transformed into the strict-feedback form from which the discrete-time model is derived by the first-order Taylor expansion. The virtual control is designed with nominal feedback and neural network (NN) approximation via back-stepping. Meanwhile, one adaptive NN controller is designed for the velocity subsystem. To avoid the circular construction problem in the practical control, the design of coefficients adopts the upper bound instead …

Adaptive Neural Control Based On Hgo For Hypersonic Flight Vehicles, Bin Xu

Bin Xu

This paper describes the design of adaptive neural controller for the longitudinal dynamics of a generic hypersonic flight vehicle (HFV) which are decomposed into two functional systems, namely the altitude subsystem and the velocity subsystem. For each subsystem, one adaptive neural controller is investigated based on the normal output-feedback formulation. For the altitude subsystem, the high gain observer (HGO) is taken to estimate the unknown newly defined states. Only one neural network (NN) is employed to approximate the lumped uncertain system nonlinearity during the controller design which is considerably simpler than the ones based on back-stepping scheme with the strict-feedback …

Task Allocation For Multi-Spacecraft Cooperation Based On Estimation Of Distribution Algorithm, Bin Xu

Bin Xu

One two-stage task allocation strategy is proposed for multi-spacecraft cooperation during the long-range orbit transfer with two impulses. This paper focuses on the task value maximum and cost minimum optimization by assigning spacecraft to different task. At the first stage time and energy cost are considered based on the spacecraft dynamics. The optimization result is together with the target value as the factor for the task allocation model at the second stage. The optimization is processed separately in continuous and discrete time domain with estimation of distribution algorithm (EDA). Different task allocation mode is formulated and the strategy is verified …

Composite Control Based On Optimal Torque Control And Adaptive Kriging Control For The Crab Rover, Bin Xu

Bin Xu

Terrainability is mostly dependant on the suspension mechanism and the control of a space rover. For the six wheeled CRAB rover, this paper presents the composite control design with torque control and adaptive Kriging control to improve the terrainability, somewhat related to minimizing heel slip. As CRAB is moving slowly, the torque control is processed by minimizing the variance of the required friction coefficient based on the static model. Adaptive Kriging control is used to track the commanded velocity. The system uncertainty is compensated by Kriging estimation based on the velocity dynamics. Experiment results with two different tires show the …

Adaptive Hypersonic Flight Control Via Back-Stepping And Kriging Estimation, Bin Xu

Bin Xu

This paper investigates the adaptive Kriging controller for the longitudinal dynamics of a generic hypersonic flight vehicle (HFV). For the altitude subsystem, the dynamics are transformed into the strict-feedback form where the backstepping scheme is employed. Considering the nonlinearity of the dynamics, the nominal feedback is included in the controller while Kriging system is designed to estimate the uncertainty. With the proposed controller, the almost surely bounded stability is guaranteed. The simulation study is presented to show the effectiveness of the proposed control approach.

Modeling Large Modern Fossil-Fueled Steam-Electric Power Plant And Its Coordinated Control System For Power System Dynamic Analysis, Lin Gao

Lin Gao

Fossil-fueled steam-electric power plants have many outstanding advantages and are still one of the main power types in the world especially for non-European countries. The classic mathematic models are designed for traditional hydraulic governing steam turbine units. Single turbine and its control system models are used wildly for dynamic analysis in power system. Digital electro-hydraulic (DEH) control systems and coordinated control systems (CCS) are used in most of the modern large power boiler-turbine units. They are key elements in the operation of the power station and have great impact on the system responses to the frequency or load disturbances. But …

Analysis Of Power System Frequency Responses With Hydro Turbines Incorporating Load Shedding, Lin Gao

Lin Gao

As shown in many recent works, the load-frequency behavior can be represented by system frequency response models especially for an islanding process. In this paper, a frequency response model incorporating an under-frequency load-shedding scheme is presented for islanding power system simulations. The model was applied for a realistic power system with hydro power generators. The hydro power generator model parameters were identified and similar responses were observed between the simulations and the accident records. The simulation results showed disadvantages of the primary frequency control systems of hydro power generators at the beginning of the load disturbances. The power system stability …

Conference Proceedings 3rd International Scientific Conference On “Energy Systems With It” At Alvsjö Fair In Association With Energitinget March 16-17 2010, Dr. Erik Dahlquist, Dr. Jenny Palm

Dr. Erik Dahlquist

2010 “The Energiting” is performed for the 12th time. The International Scientific conference is arranged for the 3rd time. The organisers are Swedish Energy Agency, Mälardalen University and the Research School for Energy Systems with LiU, KTH, UU and CTH. The first topic will be “Energy systems” covering use of renewable energy sources, energy conversion and process efficiency improvement with new technologies, as well as societal aspects of the introduction of new technologies. The second topic is “Energy and IT”. This covers energy and load management, interaction between production, distribution and “consumption”, usage of data for decision support and control, …

Selective Recursive Kernel Learning For Online Identification Of Nonlinear Systems With Narx Form, Yi Liu, Haiqing Wang, Jiang Yu, Ping Li

Dr. Yi Liu

Online identification of nonlinear systems is still an important while difficult task in practice. A general and simple online identification method, namely Selective Recursive Kernel Learning (SRKL), is proposed for multi-input–multi-output (MIMO) systems with the nonlinear autoregressive with exogenous input form. A two-stage RKL online identification framework is first formulated, where the information contained by a sample (i.e., the new arriving or old useless one) can be introduced into and/or deleted from the model, recursively. Then, a sparsification strategy to restrict the model complexity is developed to guarantee all the output channels of the MIMO model accurate simultaneously. Specially, a …

Adaptive Pid Control Based On Rbf Network Approximating The Satellite Clock Thermal Model, Bin Xu

Bin Xu

The accuracy o f t ime information prov ided by sate llite clock g reat ly depends on its frequency stab ili􀀁 ty, w hich is up to the stability o f the co re tempera ture. Th is paper introduces an adaptive PID control for the sate llite c lock system whose mode l is approx imated based on RBF neural netw orks. Simu lation resu lts demonstrate the va lid ity o f the proposed contro.l

Parameter Identification Of Hydro Generation System With Fluid Transients Based On Improved Genetic Algorithm, Lin Gao

Lin Gao

More accurate models are adopted for dynamic stability analysis of hydro generation systems but the parameters of these models are often estimated roughly. Inaccurate parameters may decrease the analysis accuracy improved by using an accurate model. An improved genetic algorithm is proposed in this paper to estimate the parameters of a hydro generation system model which contains a series of basic differential equations to represent the flow transients more accurately. The numerical and experimental results show good accordance between the actual systems and the identification results.

A New Framework For Power System Identification Based On An Improved Genetic Algorithm, Lin Gao

Lin Gao

Accuracy parameters of power system model are of great importance in stability and security evaluation or simulation. Some of the conventional methods may have inadequate adaptability or effectiveness for identification of different power systems. A general framework for power system identification is proposed based on an improved genetic algorithm with a logarithmic fitness function and an adaptive searching space. It can be used for most power system models (linear or nonlinear) and can readily be performed on different models just by rebuilt corresponding map lists between the parameters and the coefficients of the general model. The numerical experiment and practical …

Proceedings Of The Scientific Conference On Energy And It At Alvsjo Fair, Stockholm March 11-12, 2009 In Connection With The “Energitinget 2009, Dr. Erik Dahlquist, Dr. Jenny Palm

Dr. Erik Dahlquist

This book contains the proceedings from the Energy and IT conference at Alvsjo Energy conference "Energitinget" arranged by Swedish Energy Agency, with approximately 2500 visitors. The papers contain both technical and social science papers, relating to both energy efficiency in buildings and in industry.

Proceedings From Scientific Conference On Green Energy And It, Dr. Erik Dahlquist

Dr. Erik Dahlquist

This conference is part of the annual Energitinget, a national arena for energy in Sweden, with some 2500 participants. The focus with this session is to give a forum for researchers to present scientific results, and also to discuss these with other researchers. It contains papers in the area of Energy and IT as well as Green energy generally

Use Of Modeling And Simulation In Pulp And, Dr. Erik Dahlquist

Dr. Erik Dahlquist

The book is a handbook for operators and process engineers in primarily pulp and paper industry, but also other process industries about how to utilise simulation as a tool for enhanced process operations. The book has been written as part of a EU COST action on Process Simulation, with 14 countries and 50 researchers and process industry representatives involved.

An Improved Robust Projection Identification Algorithm To Manned Maneuvering Units, Bin Xu

Bin Xu

空间载人机动装置(MMU )在进行救援过程中, 其动力学参数存在很大的不确定性。为解决这一辨识问题, 本文首先推导系统关于各动力学参数的线性化模型, 然后结合该线性模型的特点, 提出了一种用于估计动力学参数的改进鲁棒投影算法, 并在理论上分析了该算法的收敛性质, 数字仿真验证了方法的有效性。

Large It Project Implementation - A Police Application Perspective, Venkateswar P. Oruganti

Venkateswar P Oruganti FIETE FIE PMP

A comprehensive Police Information System has the paramount objective to computerize activities related to Crime control, administrative support functions and interactions with other co-functionary government departments such as Judiciary, Road Transport Authority, Prisons, Hospitals, immigration etc., apart from providing timely and accurate information to citizens.

Effective implementation of such system depends primarily on the environment, processes, infrastructure, and continuity measures. The implementation of such systems will bring in an Organizational Transformation bridging the digital divide in a department in particular and in the government in general.

Seven Steps For Effective Implementation Of Police Information Systems, Venkateswar P. Oruganti

Venkateswar P Oruganti FIETE FIE PMP

Police Information Systems implementation from concept to completion is a unique experience. This presentation highlights typical of the practices and seven steps for effective implementation of Police Information Systems. This presentation is used for a webinar during the 2nd Anniversary of Oracle eGov COE at New Delhi in July 2005

Data Communication Software- Role And Functions, Raman K. Attri, Noor Jahan Haque

Raman K. Attri

The shifting of communication systems from analog to digital has introduces a new area of data communication. The core of data communication is Communication software which is the topic of my paper today. In this paper I shall cover following areas: Overview of Data Communication, Role of Data Communication Software, Functional Aspects of Data Communication Software