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Annual Conference on the Society-of-Instrument-and-Control-Engineers

作者： Yamada, Isao Ohtsuki, Tomoaki Hisanaga, Tetsuo Zheng, Li Yamtake Corp Kanagawa Japan Keio Univ Dept Informat & Comp Sci Kanagawa Japan

ISBN: (纸本)9784907764289

A lot of applications of sensor networks require the position of human and objects in indoor environment. There are some methods for this purpose. In this paper, we use received signal strength (RSS) to estimate the position. However, RSS varies substantially owing to fading, shadowing and multipath effects. Attenuation constant varies according to indoor environment. For this reason, the attenuation constant is determined before estimating the position of target node in the conventional method. We propose a position estimation method that estimates a target node position and attenuation constant simultaneously. Thus, the proposed method has no need to estimate the attenuation constant in the target environment preliminarily. To evaluate the position estimation accuracy of the proposed method, we developed the prototype system and experimented in our office. Multiple fixed target nodes were set in the target environment. The experiment presents that the proposed method has about the same accuracy as the conventional one without preliminary data collection for attenuation constant estimation.

关键词： IEEE802.15.4 position estimation maximum likelihood algorithm attenuation constant

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Adaptive recursive M-robust system parameter identification using the QQ-plot approach

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IET CONTROL THEORY AND APPLICATIONS 2011年第4期5卷 579-593页

作者： Kvascev, G. S. Djurovic, Z. M. Kovacevic, B. D. Univ Belgrade Sch Elect Engn Signal & Syst Dept Belgrade 11000 Serbia

A new adaptive algorithm for the robust estimation of parameters of linear dynamic discrete-time systems in the presence of non-Gaussian impulsive noise within a measurement sequence is proposed in this study. Starting from the theory of robust estimation, a simple, adaptive, practically applicable robust approximate maximum likelihood algorithm is derived that, in the cases of contaminated normal distribution of measurement noise, demonstrates a high level of efficiency. The QQ-plot technique, combined with data cleaning based on the robustified winsorisation technique, is used as a framework for the classification of sorted data into the class of regular normally distributed data and the class of irregular data belonging to the contaminating distribution with a variance that is much greater than nominal. The link between the QQ-plot technique and a specific linear regression is established, so that the estimation of statistical parameters of the contaminated measurement distribution is performed using the least-squares technique. Then, the suboptimal maximum likelihood criterion is defined, and the system parameter estimation problem is solved robustly, using the proposed recursive robust parameter estimation scheme. Simulation results illustrate the discussion and show the efficiency of the proposed adaptive recursive parameter estimation algorithm in the presence of glint spikes or outliers.

关键词： Other topics in statistics data cleaning adaptive control linear regression robustified winsorisation technique adaptive recursive M-robust system parameter identification linear dynamic discrete time system Stability in control theory maximum likelihood algorithm linear systems robust control Self-adjusting control systems maximum likelihood estimation impulse noise least square technique recursive estimation robust estimation Discrete control systems regression analysis QQ-plot approach adaptive algorithm sorted data classification discrete time systems non-Gaussian impulsive noise

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Identification of Mangrove Areas by Remote Sensing: The ROC Curve Technique Applied to the Northwestern Mexico Coastal Zone Using Landsat Imagery

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REMOTE SENSING 2011年第8期3卷 1568-1583页

作者： Alatorre, Luis C. Sanchez-Andres, Raquel Cirujano, Santos Begueria, Santiago Sanchez-Carrillo, Salvador UACJ Div Multidisciplinaria Cuauhtemoc Chihuahua Mexico CSIC Inst Pirenaico Ecol E-50080 Zaragoza Spain CSIC Real Jardin Bot E-28014 Madrid Spain CSIC Estn Expt Aula Dei Zaragoza 50059 Spain CSIC Museo Nacl Ciencias Nat E-28006 Madrid Spain

In remote sensing, traditional methodologies for image classification consider the spectral values of a pixel in different image bands. More recently, classification methods have used neighboring pixels to provide more information. In the present study, we used these more advanced techniques to discriminate between mangrove and non-mangrove regions in the Gulf of California of northwestern Mexico. A maximum likelihood algorithm was used to obtain a spectral distance map of the vegetation signature characteristic of mangrove areas. Receiver operating characteristic (ROC) curve analysis was applied to this map to improve classification. Two classification thresholds were set to determine mangrove and non-mangrove areas, and two performance statistics (sensitivity and specificity) were calculated to express the uncertainty (errors of omission and commission) associated with the two maps. The surface area of the mangrove category obtained by maximum likelihood classification was slightly higher than that obtained from the land cover map generated by the ROC curve, but with the difference of these areas to have a high level of accuracy in the prediction of the model. This suggests a considerable degree of uncertainty in the spectral signatures of pixels that distinguish mangrove forest from other land cover categories.

关键词： remote sensing maximum likelihood algorithm curve ROC mangrove sensitivity/specificity Gulf of California

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Electromyographic Assessment of Muscle Fatigue During Isometric Vibration Training at Varying Frequencies

Electromyographic Assessment of Muscle Fatigue During Isomet...

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32nd Annual International Conference of the IEEE Engineering-in-Medicine-and-Biology-Society (EMBC 10)

作者： Mischi, M. Rabotti, C. Cardinale, M. Eindhoven Univ Technol Dept Elect Engn NL-5600 MB Eindhoven Netherlands British Olymp Assoc London England Univ Aberdeen Coll Life Sci & Med Aberdeen AB9 1FX Scotland

ISBN: (纸本)9781424441242

Resistance exercise is essential to improve or maintain muscle performance. Vibration training has been suggested as an alternative option for muscle conditioning, aiming especially at improving muscle strength and power. Several studies link the effects of vibration training to enhanced neuromuscular stimulation, measured by electromyography (EMG) and typically ascribed to involuntary reflex mechanisms. However, the underlying mechanisms are still unclear, limiting the use of vibration training. This paper proposes additional methods to analyze the mechanisms involved in vibration training. A dedicated measurement setup was realized to relate vibration parameters to muscle fatigue in the biceps brachii. Fatigue is estimated by EMG mean frequency and conduction velocity assessments as well as by maximum voluntary contraction (MVC) force measurements. A modified maximum likelihood algorithm is proposed for the conduction velocity estimation based on high-density EMG recording. Five volunteers performed four isometric contractions of 50 s at 80% MVC with no vibration (control) and with superimposed vibration at 20, 30, and 40 Hz. Fatigue was estimated from the decay of force, EMG mean frequency, and EMG conduction velocity. 30-Hz vibrations represented the most fatiguing stimulus. Our preliminary results also show a better correlation between force and conduction velocity decay than between force and mean frequency decay, indicating the former as a better EMG indicator of fatigue. The proposed methods provide important advancements for the analysis of vibration exercise and guidance towards the definition of optimal training protocols.

关键词： EMG biceps brachii biomechanics conduction velocity dedicated measurement electromyographic assessment electromyography electromyography fatigue involuntary reflex mechanisms isometric vibration training maximum likelihood algorithm maximum likelihood estimation maximum voluntary contraction force measurements mean frequency mechanical strength medical signal processing muscle conditioning muscle fatigue muscle power muscle strength neuromuscular stimulation resistance exercise vibrations

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Estimation of the Velocity Vector of a Moving Object with Unknown Intensities of Its Image and Background

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OPTOELECTRONICS INSTRUMENTATION AND DATA PROCESSING 2010年第3期46卷 207-214页

作者： Trifonov, A. P. Kutsov, R. V. Baranov, S. O. Voronezh State Univ Univ Skaya Pl 1 Voronezh 394006 Russia

A maximum likelihood algorithm for estimating the velocity vector of a moving object from its image of unknown intensity against an applicative background whose intensity may be unknown a priori was designed and analy... 详细信息

关键词： applicative model moving object estimate velocity vector unknown intensities maximum likelihood algorithm anomalous errors

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Phylogenetic analysis of hepatitis B virus full-length genomes reveals evidence for a large nosocomial outbreak in Belgium

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JOURNAL OF CLINICAL VIROLOGY 2009年第1期46卷 61-68页

作者： Pourkarim, Mahmoud Reza Verbeeck, Jannick Rahman, Mustafizur Amini-Bavil-Olyaee, Samad Forier, An-Marie Lerney, Philippe Maes, Piet Van Ranst, Marc Univ Louvain Lab Clin Virol Rega Inst Med Res BE-3000 Louvain Belgium IBTO Res Ctr Tehran Iran Int Ctr Diarrhoeal Dis Res Dhaka 1000 Bangladesh Pasteur Inst Iran Dept Biotechnol Tehran 13164 Iran Flemish Agcy Care & Hlth Div Publ Hlth Surveillance Infect Dis Control Unit Hasselt Belgium

Background: Hepatitis B virus (HBV) is primarily transmitted from mother to child, by sexual contact, intravenous drug abuse, or unsafe health care-related injection practices. Despite increased safety efforts, nosocomial acquired hepatitis B infection remains problematic. Objectives: A large HBV outbreak was investigated comprising 36 patients with acute HBV infection in a primary care physician's practice. Study design: In a retrospective study (2003-2008), 36 serum samples from patients with acute HBV infection were collected. They had received several injections by the same physician at least 3 months before the onset of clinical symptoms. As a control group, sera were collected from HBV patients from other physicians from the same province. Full-length HBV genomes were amplified and were phylogenetically analysed. Results: HBV complete genomes of 32 patients were successfully amplified and sequenced, and clustered together with the reference genotype A. subgenotype A2 strains. We also analysed 26 control HBV genotype A samples. All 32 HBV strains from the patient group clustered in a monophyletic branch with a bootstrap value of 100, whereas the control samples branched separately in another clade. The genetic distance value showed small differences within the patients group, whereas the rate within the control group was seven times higher. These observations confirm that the source of transmission was clearly different in both groups. Conclusion: maximum likelihood analysis and genetic distance calculations based on the full-length genomes of HBV strains isolated from patients and controls provided strong evidence for a common nosocomial source of infection for all 32 patient cases. (C) 2009 Published by Elsevier B.V.

关键词： Hepatitis B virus Nosocomial outbreak Phylogenetic analysis maximum likelihood algorithm Full-length genome Belgium

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The Application of Mixed Genetic algorithm in Parameter Identification of Circulating Fluidized Bed Units

The Application of Mixed Genetic Algorithm in Parameter Iden...

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International Conference on Sustainable Power Generation and Supply

作者： Han, Pu Wang, Zijie Huang, Yu N China Elect Power Univ Sch Control Sci & Engn Beijing 071003 Peoples R China

ISBN: (纸本)9781424449347

The maximum likelihood algorithm has some requirements regarding the initial values, or else there would be no guarantee for the convergence of the parameters. The Genetic algorithm (GA) was introduced in this paper to cope with the problem of local convergence in maximum likelihood algorithm. The typical function test showed that the method had manifested both the global convergence as in GA and the high accuracy rate as in maximum likelihood algorithm. Besides, the special software for general model identification was designed for identification in typical thermal systems. The results showed that it was a readable and valuable method in the realm of identification

关键词： Thermal process System identification Mixed Genetic algorithm maximum likelihood algorithm

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A novel wavelet packet division multiplexing based on maximum likelihood algorithm and optimum pilot symbol assisted modulation for Rayleigh fading channels

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CIRCUITS SYSTEMS AND SIGNAL PROCESSING 2005年第3期24卷 287-302页

作者： Zhou, L Li, JD Liu, J Zhang, GH Xidian Univ State Key Lab Integrated Serv Networks Broadband Wireless Commun Lab Inst Sci Informat Xian 710071 Peoples R China

Wavelet packet division multiplexing (WPDM) is a high-capacity, flexible, and robust multiple-signal transmission technique. In this paper, a novel WPDM system based on optimum pilot symbol assisted modulation (OPSAM) and a maximum likelihood (NIL) algorithm is studied for Rayleigh fading channels. The NIL detecting algorithm and the new discrete wavelet packet transform structure, which is based on pilot symbol assisted modulation (PSAM) using a least mean squares algorithm, are two novel aspects of the presented system. An expression for the bit error rate of the WPDM scheme on quadrature phase-shift keying (QPSK) is derived in the presence of flat fading and Gaussian noise. It is demonstrated by simulation results that the OPSAM WPDM scheme can provide greater immunity to flat fading channels and Gaussian noise than the OPSAM orthogonal frequency division multiplexing scheme, the differential QPSK WPDM scheme, and the normal PSAM WPDM scheme.

关键词： wavelet packet division multiplexing pilot symbol assisted modulation maximum likelihood algorithm

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Detection of a Moving Object without a priori Information about the Velocity Vector and Image and Background Intensities

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OPTOELECTRONICS INSTRUMENTATION AND DATA PROCESSING 2009年第1期45卷 22-29页

作者： Trifonov, A. P. Kutsov, R. V. Voronezh State Univ Univ Pl 1 Voronezh 394006 Russia

Synthesis and analysis of the maximum likelihood algorithm of detecting an object extended in space are performed. The influence of the absence of a priori information on the velocity vector of object motion and image... 详细信息

关键词： applicative model detection unknown velocity vector of object motion unknown intensities maximum likelihood algorithm

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A topological transformation in evolutionary tree search methods based on maximum likelihood combining p-ECR and neighbor joining

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BMC BIOINFORMATICS 2008年第s6期9卷 S4-S4页

作者： Guo, Mao-Zu Li, Jian-Fu Liu, Yang Harbin Inst Technol Dept Comp Sci & Technol Harbin 150001 Peoples R China

Background: Inference of evolutionary trees using the maximum likelihood principle is NP-hard. Therefore, all practical methods rely on heuristics. The topological transformations often used in heuristics are Nearest Neighbor Interchange (NNI), Subtree Prune and Regraft (SPR) and Tree Bisection and Reconnection (TBR). However, these topological transformations often fall easily into local optima, since there are not many trees accessible in one step from any given tree. Another more exhaustive topological transformation is p-Edge Contraction and Refinement (pECR). However, due to its high computation complexity, p-ECR has rarely been used in practice. Results: To make the p-ECR move more efficient, this paper proposes a new method named p-ECRNJ. The main idea of p-ECRNJ is to use neighbor joining (NJ) to refine the unresolved nodes produced in p-ECR. Conclusion: Experiments with real datasets show that p-ECRNJ can find better trees than the best known maximum likelihood methods so far and can efficiently improve local topological transforms in reasonable time.

关键词： Evolutionary Tree Neighbor Join maximum likelihood algorithm Local Topological Topological Transformation

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