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algorithm of heating temperature for Chongqing's winter greenhouses

Journal of Chongqing University 2007年第1期6卷 50-54页

作者：谢守勇 LI Xi-wen YANG Shu-zi YANG Ming-jin School of Mechanical Science ＆ Engineering Huazhong University of Science ＆ Technology Wuhan 430074P.R. China School of Engineering Southwest University Chongqing 400716 P. R. China

Internal temperature is crucial to plant growth in the greenhouse. We investigated the patterns of constructing and managing greenhouses in Chongqing, and developed an algorithm of heating temperature for closed winter plastic greenhouses under the conditions of no man-made illumination, no ventilation and hot wind machine as the heating equipment, which are the most adopted pattern of greenhouses in Chongqing area. The algorithm includes two functions of temperature outside the greenhouse, which calculate the values of the warming estimation coefficient (WEC) and the gap between temperatures inside and outside the greenhouse with the measured data of outside temperature, and then give the value of internal temperature; the heat rating of heating facilities required by a greenhouse can be determined by this algorithm with given values of floor area and internal temperature, measured outside temperature and calculated WEC. Verification of the algorithm demonstrates a desirable accuracy of estimation. algorithms of computing heating temperature for greenhouses of different constructing and managing patterns and in different geographic conditions can also be derived in a similar way. This research presents a paradigm for developing a feasible method to fit out greenhouses with appropriate heating facilities, aiming at energy efficient and cost efficient production.

关键词： heating balance equation warming estimation coefficient estimation algorithm

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MODELLING BIOLOGICAL VARIATION: AN algorithm FOR PARAMETER DISTRIBUTION estimation.

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IFAC Proceedings Volumes 2006年第1期39卷 452-457页

作者： S.T. Bell A.E. McKinnon A.R. Sykes Agriculture and Life Science Division Applied Computing Group Lincoln University New Zealand

Parameters in a dynamic model of magnesium metabolism in dairy cattle were implemented as distributions to represent biological variation between individual animals, thus allowing calculation of the proportion of animals in the herd at risk of developing hypomagnesaemic tetany by Monte-Carlo simulation. This paper describes an algorithm developed to refine a priori parameter distribution estimates, and discusses its principles of operation, performance, and convergence properties. When the estimated parameter distributions are used in the model they generate a response distribution of the model of the required accuracy. The algorithm is specified in general terms permitting application to other models.

关键词： Biological System Mathematical Modelling Monte-Carlo Parameter Distribution estimation algorithm

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Motor threshold in transcranial magnetic stimulation:: comparison of three estimation methods

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NEUROPHYSIOLOGIE CLINIQUE-CLINICAL NEUROPHYSIOLOGY 2006年第1期36卷 1-7页

作者： Tranulis, C Guéguen, B Pham-Scottez, A Vacheron, MN Cabelguen, G Costantini, A Valero, G Gatinovski, A Ctr Hosp St Anne Serv Neurophysiol Clin F-75014 Paris France Ctr Hosp St Anne Serv Hosp Univ Sante Mentale & Therapeut Pr H Loo F-75014 Paris France Ctr Hosp St Anne Clin Malad Mentales & Encephale F-75014 Paris France Ctr Hosp St Anne Psychiat Serv Secteur 13 F-75014 Paris France

Aims. - Motor threshold (MT) is an important parameter for the practice of transcranial magnetic stimulation. Our goat was to compare three methods to estimate MT in a clinical setting. Methods. - Comparison of three MT estimation algorithms: 1) the Rossini-Rothwell method consists in lowering stimulus intensity until only five positive responses out of 10 trials are recorded, defining MT;2) the Mills-Nithi method considers the MT as the mean of an upper threshold (10 positive out of 10 trials) and a lower threshold (0 out of 10 trials);3) the supervised parametric method estimates the MT by fitting (mathematically and graphically) a sigmoid function on raw data obtained by stimulation at variable intensities. Six MT estimations (two per method) were recorded in a single session in 10 healthy subjects. Results. - The within-subject variation of MT (expressed as % of the mean MT +/- standard deviation) during a single session was of 8.5 +/- 7.2% for the Rossini-Rothwell method, 8.7 +/- 5.7% for the Mills-Nithi method and 9.5 +/- 4.0% for the supervised parametric method. No significant differences in variability of MT estimation were found between the methods, but the Rossini-Rothwell method was significantly shorter (half the number of stimuli compared to the two other methods). Conclusion. - In our setting, Rossini-Rothwelt method was superior to the two other methods. The variability of MT estimation measured in our study is important, yet acceptable for clinical applications. However, this variability can be a source of considerable errors in excitability studies and should be a focus of future research. (c) 2006 Elsevier SAS. All rights reserved.

关键词： motor threshold transcranial magnetic stimulation estimation algorithm Rossini-Rothwell algorithm Mitts-Nithi algorithm

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Sigma point Kalman filter for bearing only tracking

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SIGNAL PROCESSING 2006年第12期86卷 3769-3777页

作者： Sadhu, S. Mondal, S. Srinivasan, M. Ghoshal, T. K. Jadavpur Univ Dept Elect Engn Kolkata 700032 W Bengal India Indian Inst Technol Dept Mech Engn Kharagpur 721302 W Bengal India

Relative merits of sigma point Kalman filters (SPKF), also known as unscented Kalman filters (UKF) vis-a-vis extended Kalman, filter (EKF) and iterated extended Kalman filter (IEKF) for a bearing-only target-tracking problem using rms error and robustness with respect to outlier initial conditions are explored. After establishing that the rms error performance obtainable by SPKF/UKF and IEKF for this fairly severe non-linear system is similar to those obtainable from other competing techniques, the relative robustness of IEKF, SPKF/UKF and EKF with respect to large initial condition uncertainty (a common occurrence for this class of tracking problems) is investigated. Using several versions of SPKF/UKF, it is shown that SPKF is about 20 times more robust compared to EKF. It is illustrated that the additional design freedom available with a scaled version of SPKF/UKF may be utilised for further improvement of the robustness. The main contribution of this paper is quantification of relative robustness of these non-linear filters. A simplified criterion is suggested and used for quantifying track loss and the relative occurrence of such track loss in batch Monte Carlo simulation has been used as a measure of (lack of) robustness. As the SPKF/UKF does not introduce substantial computational burden, when compared to EKF, it is argued that SPKF/UKF algorithm may become a strong candidate for on-board implementation. (c) 2006 Elsevier B.V. All rights reserved.

关键词： bearings-only tracking estimation algorithm extended Kalman filter unscented Kalman filter filtering techniques Monte Carlo simulation target tracking filters sigma point filters

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A floating-point FPGA-based self-tuning regulator

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IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS 2006年第2期53卷 693-704页

作者： Salcic, Z Cao, JY Nguang, SK Univ Auckland Dept Elect & Comp Engn Auckland 1020 New Zealand

Recursive-least-square (RLS) algorithm is widely used in many areas with real-time implementation using digital signal processors. In this paper, the authors present a pure hardware implementation of a self-tuning regulator (STR) that uses a real-time RLS algorithm as the parameter estimator. The STR contains a controller design circuit and a controller circuit. Due to RLS computation-precision and dynamic-range requirements, the hardware implementation uses a floating-point format. The floating-point processing elements presented in this paper use parameterized design, where the number of exponents and mantissa bits can be changed as the data range and the accuracy of a specific application require. The strategies for overcoming the covariance matrix asymmetrical problem during the hardware computation and the covariance matrix resetting is introduced when the system is poorly exciting are presented. The design was verified with real-time experiments using a new testbed. The experiment results are presented.

关键词： digital signal processor (DSP) estimation algorithm field-programmable gate array (FPGA) floating-point arithmetic floating-point format recursive least squares (RLS) self-tuning regulator (STR)

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Failure analysis on China power grid based on power law

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控制理论与应用（英文版） 2006年第3期4卷 235-238页

作者： Xiaofeng WENG Yiguang HONG Ancheng XUE Shengwei MEI State Key Lab of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China Institute of Systems Science Chinese Academy of Sciences Beijing 100080 China

This paper is concerned with the mechanism of blackouts in China power system from the viewpoint of self-organized criticality. By using two estimation algorithms of scaled window variance （SWV） and rescaled rangestatistics （R/S）, this paper studies the blackout data in China power system during 1988-1997. The result of analysis shows that the blackout data of 1994-1997 coincides well with the autocorrelation. Furthermore, it is found that the function of blackout probability vs. blackout size exhibits power law distribution.

关键词： Power system Blackout Power law estimation algorithm

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OPTIMAL LAG STRUCTURE SELECTION IN VEC–MODELS

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IFAC Proceedings Volumes 2005年第1期38卷 89-94页

作者： Peter Winker Dietmar Maringer Department of Economics Law and Social Sciences University of Erfurt Germany

For the modelling of time series, multivariate linear and nonlinear systems of equations became a standard tool. These models are also applied for non-stationary processes. However, estimation results in finite samples might depend on the specification of the model dynamics. We propose a method for automatic identification of the dynamic part of VEC–models. Model selection is based on a modified information criterion. The resulting complex discrete optimization problem is tackled using a hybrid heuristic. We present the algorithm and results of a simulation study indicating the performance both with regard to the dynamic structure and the rank selection in the VEC–model.

关键词： Time series analysis variable structure error correction estimation algorithm heuristic searches

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Fuzzy controller design by means of genetic optimization and NFN-based estimation technique

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INTERNATIONAL JOURNAL OF CONTROL AUTOMATION AND SYSTEMS 2004年第3期2卷 362-373页

作者： Oh, SK Rho, SB Kim, HK Wonkwang Univ Dept Elect Elect & Informat Engn Iksan 570749 Chonbuk South Korea Univ Suwon Dept Elect Engn Hwanseong 445743 Gyeonggi Do South Korea

In this study, we introduce a noble neurogenetic approach to the design of the fuzzy controller. The design procedure dwells on the use of Computational Intelligence (CI), namely genetic algorithms and neurofuzzy networks (NFN). The crux of the design methodology is based on the selection and determination of optimal values of the scaling factors of the fuzzy controllers, which are essential to the entire optimization process. First, tuning of the scaling factors of the fuzzy controller is carried out, and then the development of a nonlinear mapping for the scaling factors is realized by using GA based NFN. The developed approach is applied to an inverted pendulum nonlinear system where we show the results of comprehensive numerical studies and carry out a detailed comparative analysis.

关键词： Computational Intelligence (CI) estimation algorithm fuzzy controller genetic algorithms neurofuzzy networks (NFN) optimization process scaling factors

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Design elements of a small low-cost autonomous underwater vehicle for field experiments in multi-vehicle coordination

Design elements of a small low-cost autonomous underwater ve...

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IEEE/OES Autonomous Underwater Vehicles Conference

作者： Stilwell, DJ Gadre, AS Sylvester, CA Cannell, CJ Virginia Tech Blacksburg VA 24060 USA

ISBN: (纸本)0780385438

Field operations with multiple autonomous underwater vehicles are often expensive and logistically complex, yet the development of decentralized control and estimation algorithms suitable for cooperating autonomous vehicles requires in situ testing and experimentation. Toward the goal of creating a field-deployable testbed for multi-vehicle control and estimation algorithms, a small, inexpensive autonomous underwater vehicle has been developed. Design features of the AUV are presented along with design trade-offs imposed by developing an AUV that is small, inexpensive, yet fully-field deployable.

关键词： underwater vehicles mobile robots decentralised control control system synthesis multi-robot systems multivehicle coordination multiple autonomous underwater vehicle decentralized control estimation algorithm decentralised control Autonomous underwater vehicles underwater vehicles multi-robot systems control system synthesis Mobile robots Design factors field experimentation Field operations In situ tests design features

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Development of Navigation algorithm Architecture for Automatic Landing Based on Landmarks Image Processing

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IFAC Proceedings Volumes 2004年第6期37卷 257-262页

作者： Young Mok Hyun Nikolai V. Kim Moscow Aviation Institute (State Technical University) 4 Volokolamskoe shosse 125993 Moscow Russia

This paper discusses navigation algorithm architecture for estimating aircraft position and attitude during approach and landing using landmarks image processing of the Earth. In general, automatic landing can be realized with the help of high accuracy real-time estimation of aircraft position and attitude. In the proposed algorithm, the reference images of the Earth surface saved in the onboard memory are matched with the current images captured from onboard electro-optical camera. The matching information is used for INS correction by means of the Kalman filter with a radio altimeter. For application of this algorithm architecture, image matching algorithm and decision of more informative reference images for improvement in matching efficiency have been studied. The results indicate that it is possible to use the proposed navigation algorithm for aircraft automatic landing without the use of ground equipment.

关键词： aircraft automatic landing estimation algorithm image matching accuracy

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