5,930 research outputs found

    A Hybrid Global Minimization Scheme for Accurate Source Localization in Sensor Networks

    Get PDF
    We consider the localization problem of multiple wideband sources in a multi-path environment by coherently taking into account the attenuation characteristics and the time delays in the reception of the signal. Our proposed method leaves the space for unavailability of an accurate signal attenuation model in the environment by considering the model as an unknown function with reasonable prior assumptions about its functional space. Such approach is capable of enhancing the localization performance compared to only utilizing the signal attenuation information or the time delays. In this paper, the localization problem is modeled as a cost function in terms of the source locations, attenuation model parameters and the multi-path parameters. To globally perform the minimization, we propose a hybrid algorithm combining the differential evolution algorithm with the Levenberg-Marquardt algorithm. Besides the proposed combination of optimization schemes, supporting the technical details such as closed forms of cost function sensitivity matrices are provided. Finally, the validity of the proposed method is examined in several localization scenarios, taking into account the noise in the environment, the multi-path phenomenon and considering the sensors not being synchronized

    Optimization strategy for actuator and sensor placement in active structural acoustic control

    Get PDF
    In active structural acoustic control the goal is to reduce the sound radiation of a structure by means of changing the vibrational behaviour of that structure. The performance of such an active control system is to a large extent determined by the locations of the actuators and sensors. In this work an approach is presented for the optimization of the actuator and sensor locations. The approach combines a numerical modelling technique, for predicting the control performance, and genetic optimization, to find the optimal actuator and sensor locations. The approach is tested for a setup consisting of clamped rectangular plate with a piezoelectric actuator and either structural or acoustic sensors. The results show that a control system with optimal actuator and sensor configuration outperforms an arbitrary chosen configuration in terms of reduction in radiated sound power

    Genetic Algorithm in the Optimization of the Acoustic Attenuation System

    Full text link
    [EN] It is well known that Genetic Algorithms (GA) is an optimization method which can be used in problems where the traditional optimization techniques are difficult to be applied. Sonic Crystals (SC) are periodic structures that present ranges of sound frequencies related with the periodicity of the structure, where the sound propagation is forbidden. This means that in the acoustic spectrum there are ranges of frequencies with high acoustic attenuation. This attenuation can be improved producing vacancies in the structure. In this paper we use a parallel implementation of a GA to optimize those structures, by means of the creation of vacancies in a starting SC, in order to obtain the best acoustic attenuation in a predetermined range of frequencies. The cost function used in GA is based on the Multiple Scattering Theory (MST), which is a self consistent method for calculating acoustic pressure in SCs. As a final result we achieve a quasi ordered structures that presents a high acoustic attenuation in a predetermined range of frequencies, independent of the periodicity of the SC.The authors acknowledge financial support provided by the Spanish MEC (Project No. MAT2006-03097) and by the Generalitat Valenciana (Spain) under Grant No. GV/2007/191. This work also has been partially supported by MEC (Spanish government) and FEDER funds: projects DPI2005-07835, DPI2004- 8383-C03-02 and GVA-026.Romero García, V.; Fuster García, E.; Sánchez Pérez, JV.; García Raffi, LM.; Blasco, X.; Herrero Durá, JM.; Sanchís Saez, J. (2007). Genetic Algorithm in the Optimization of the Acoustic Attenuation System. Lecture Notes in Computer Science. 4507:614-621. https://doi.org/10.1007/978-3-540-73007-1_74S6146214507Martínez-Sala, R., Sancho, J., Sánchez Pérez, J.V., Llinares, J., Meseguer, F.: Sound attenuation by sculpture. Nature (London) 387, 241 (1995)Hushwaha, M.S., Halevi, P., Martínez, G., Dobrynski, L., Djafari-Rouhani, B.: Theory of acoustic band structure of periodic elastic composites. Phys. Rev. B 49(4), 2313–2322 (1994)Liu, Z., Zhang, X., Mao, Y., Zhu, Y.Y., Yang, Z., Xhan, C.T., Sheng, P.: Locally resonatn sonic materials. Science 289, 1734 (2000)Hu, X., Chan, C.T., Zi, J.: Two dimensional sonic crystals with Helmholtz resonators. Phys. Rev. E 71, 055601 (2005)Umnova, O., Attenborough, K., Linton, C.M.: Effects of porous covering on sound attenuation by poriodi arrays of cylinders. J. Acoust. Soc. Am. 119, 278 (2006)Caballero, D., Sánchez-Dehesa, J., Martínez-Sala, R., Rubio, C., Sánchez Pérez, J.V.S., Sanchis, L., Meseguer, F.: Suzuki phase in two-dimensional sonic crystals. Phys. Rev. B 64, 064303 (2001)Hakansson, A., Sánchez-Dehesa, J., Sanchis, L.: Acoustic lens design by genetic algorithms. Phys. Rev. B 70, 214302 (2004)Romero-García, V., Fuster, E., García-Raffi, L.M., Sánchez-Pérez, E.A., Sopena, M., Llinares, J., Sánchez-Pérez, J.V.: Band gap creation using quasiordered strutures based on sonic crystals. Appl. Phys. Lett. 88, 174104-1 174104-3 (2006)Chen, Y.Y., Ye, Z.: Theoretical analysis of acoustic stop bands in two-dimensional periodic scattering arrays. Phys. Rev. E 64, 036616 (2001)Economou, E.N., Sigalas, M.M.: Classical wave propagation in periodic structures: Cermet versus network topology. Phys. Rev. B 48(18), 13434 (1993)Sigalas, M.M., Economou, E.N., Kafesaki, M.: Spectral gaps for electromagnietic and scalar waves: Possible explanation for certain differences. Phys. Rev. B 50(5), 3393 (1994)Goldberg, D.E.: Genetic Algorithms in search, optimization and machine learning. Addison-Wesley, London (1989)Bäck, T.: Evolutionaty Algorithms in theory and practice. Oxford University Press, New York (1996)Baker, J.E.: Reducing bias and inefficiency in the selection algorithm. In: Proc. Second International Conference on Genetic Algorithms (1987)Mühlenbein, H., Schlierkamp-Voosen, D.: Predictive Models for the Breeder Genetic Algorithm I. Continuous Parameter Optimization. Evolutionary Computation 1(1) (1993)Cantú-Paz, E.: A summary of resaearch on parallel genetic algorithms. Technical Report 95007, Illinois Genetic Algorithms Laboratory. IlliGAL (1995

    Structural Health Monitoring of Large Structures Using Acoustic Emission-Case Histories

    Get PDF
    Acoustic emission (AE) techniques have successfully been used for assuring the structural integrity of large rocket motorcases since 1963 [...

    On the control of propagating acoustic waves in sonic crystals: analytical, numerical and optimization techniques

    Get PDF
    El control de las propiedades acústicas de los cristales de sonido (CS) necesita del estudio de la distribución de dispersores en la propia estructura y de las propiedades acústicas intrínsecas de dichos dispersores. En este trabajo se presenta un estudio exhaustivo de diferentes distribuciones, así como el estudio de la mejora de las propiedades acústicas de CS constituidos por dispersores con propiedades absorbentes y/o resonantes. Estos dos procedimientos, tanto independientemente como conjuntamente, introducen posibilidades reales para el control de la propagación de ondas acústicas a través de los CS. Desde el punto de vista teórico, la propagación de ondas a través de estructuras periódicas y quasiperiódicas se ha analizado mediante los métodos de la dispersión múltiple, de la expansión en ondas planas y de los elementos finitos. En este trabajo se presenta una novedosa extensión del método de la expansión en ondas planas que permite obtener las relaciones complejas de dispersión para los CS. Esta técnica complementa la información obtenida por los métodos clásicos y permite conocer el comportamiento evanescente de los modos en el interior de las bandas de propagación prohibida del CS, así como de los modos localizados alrededor de posibles defectos puntuales en CS. La necesidad de medidas precisas de las propiedades acústicas de los CS ha provocado el desarrollo de un novedoso sistema tridimensional que sincroniza el movimiento del receptor y la adquisición de señales temporales. Los resultados experimentales obtenidos en este trabajo muestran una gran similitud con los resultados teóricos. La actuación conjunta de distribuciones de dispersores optimizadas y de las propiedades intrínsecas de éstos, se aplica para la generación de dispositivos que presentan un rango amplio de frecuencias atenuadas. Se presenta una alternativa a las barreras acústicas tradicionales basada en CS donde se puede controlar el paso de ondas a su través. Los resultados ayudan a entender correctamente el funcionamiento de los CS para la localización de sonido, y para el guiado y filtrado de ondas acústicas.Romero García, V. (2010). On the control of propagating acoustic waves in sonic crystals: analytical, numerical and optimization techniques [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8982Palanci

    Optimization of sonic crystal attenuation properties by ev-MOGA multiobjective evolutionary algorithm

    Full text link
    [EN] This paper shows a promising method for acoustic barrier design using a new acoustic material called Sonic Crystals (SCs). The configuration of these SCs is set as a multiobjective optimization problem which is very difficult to solve with conventional optimization techniques. The paper presents a new parallel implementation of a Multiobjective Evolutionary Algorithm called ev-MOGA (also known as (sic)-MOGA) and its application in a complex design problem. ev-MOGA algorithm has been designed to converge towards a reduced, but well distributed, representation of the Pareto Front (solution of the multiobjective optimization problem). The algorithm is presented in detail and its most important properties are discussed. To reduce the ev-MOGA computational cost when.Partially supported by MEC (Spanish Government) and FEDER funds: projects DPI2005-07835, MAT2006-03097 and Generalitat Valenciana (Spain) projects GV06/026, GV/2007/191Herrero Durá, JM.; Garcia-Nieto, S.; Blasco, X.; Romero García, V.; Sánchez Pérez, JV.; García-Raffi, LM. (2009). Optimization of sonic crystal attenuation properties by ev-MOGA multiobjective evolutionary algorithm. Structural and Multidisciplinary Optimization. 39(2):203-215. https://doi.org/10.1007/s00158-008-0323-7S203215392Alander J (2002) An indexed bibliography of genetic algorithms & pareto and constrainedoptimization. Tech Rep, Dpt of Information Technology, University of VaasaCantú-Paz E (1997) A survey of parallel genetic algorithms. Tech Rep 97003, Illimois Genetic Algorithms LaboratotyCervera F, Sanchis L, Sánchez-Pérez JV, Martínez-Sala R, Rubio C, Meseguer F, López C, Caballero D, Sánchez-Dehesa J (2002) Refractive acoustic devices for airborne sound. Phys Rev Lett 88:0239021–0239024Chen Y, Ye Z (2001) Theoretical analysis of stop bands in two-dimensional periodic scattering arrays. Phys Rev E 64:036616Coello C, Toscano G, Mezura E (2005) Information processing with evolutionary algorithms. In: Grana M, Duro R, d’Anjou A, Wang PP (eds) Information processing with evolutionary algorithms: from industrial applicationsto academic speculations. Springer, New York, pp 213–231Coello C, Veldhuizen D, Lamont G (2002) Evolutionary algorithms for solving multi-objective problems. Kluwer, DordrechtDeb K (2007) Current trends in evolutionary multi-objective optimization. Int J Simul Multidiscipl Des Optim 1:1–8Eshelman LJ (1991) The chc adaptive search algorithm: how to have safe search when engaging in nontraditional genetic recombination. In: Proceedings of the first workshop on foundations of genetic algorithms. Morgan Kaufmann, San Francisco, pp 265–283Fonseca C, (1995) Multiobjective genetic algorithms with application to control engineeringproblems. PhD thesis, Dpt of Automatic Control and Systems Engineering, University of SheffieldFuster E, Romero-García V, García-Raffi LM, Sánchez-Pérez EA, Sopena M, Sánchez-Pérez JV (2006) A phenomenological model for sonic crystals based on artificial neural networks. J Acoust Soc Am 120(2):1–6García-Pablos D, Sigalas M, de Espinosa FM, Torres M, Kafesaki M, García, N (2000) Theory and experiments on elastic band gaps. Phys Rev Lett 84:4349–4352Gazonas GA, Weile DS, Wildman R, Mohan A (2006) Genetic algorithm optimization of phononic bandgap structures. Int J Solids Struct 43:5851–5866Hakkansson A, Cervera F, Sánchez-Dehesa J (2005) Sound focusing by flat acoustic lenses without negative refraction. Appl Phys Lett 86:0541021–0541023Herrero J, Blasco X, Martínez M, Ramos C, Sanchis J (2007) Non-linear robust identification of a greenhouse model using multi-objective evolutionary algorithms. Biosyst Eng 98(3):335–346Herrero JM (2006) Non-linear robust identification using evolutionary algorithms. PhD thesis, Universidad Politécnica de Valencia, ValenciaHussein MI, Hamza K, Hulbert GM, Saitou K (2007) Optimal synthesis of 2d phononic crystals for broadband frequency isolation. Waves Random Complex Media 17(4):491–510Hussein MI, Hamza K, Hulbert GM, Scott RA, Saitou K (2006) Multiobjective evolutionary optimization of periodic layered materials for desired wave dispersion characteristics. Struct Multidisc Optim 31:60–75Kafesaki M, Economou E (1999) Multiple scattering theory for three-dimensional periodic acoustic composites. Phys Rev B 60:11993Kohn W, Rostoker N (1954) Solution of the schrodinger equation in periodic lattices with an aplication to metallic lithium. Phys Rev 94:1111Korringa J (1947) On th calculation of the energy of a bloch wave in a metal. Physica XIII:392Kushwaha M (1997) Stop-bands for periodic metallic rods: Sculptures that can filter the noise. Appl Phys Lett 70:3218–3220Laumanns M, Thiele L, Deb K, Zitzler E (2002) Combining convergence and diversity in evolutionary multi-objective optimization. Evol Comput 10(3):263–282Martínez-Sala R, Sancho J, Sánchez J, Gómez V, Llinares J, Meseguer F (1995) Sound attenuation by sculpture. Nature 378:241Miettinen KM (1998) Nonlinear multiobjective optimization. Kluwer, DordrechtMishra S, Deb K, Mohan M (2005) Evaluating the ε-domination based multi-objective evolutionary algorithm for a quick computation of pareto-optimal solutions. Evol Comput 13(4):501–526Romero-García V, Fuster E, García-Raffi LM, Sánchez-Pérez EA, Sopena M, Llinares J, Sánchez-Pérez JV (2006) Band gap creation using quasiordered structures based on sonic crystals. Appl Phys Lett 88:1741041–17410413Sánchez-Pérez JV, Caballero D, Martínez-Sala R, Rubio C, Sánchez-Dehesa J, Meseguer F, Llinares J, Gálvez F (1998) Sound attenuation by a two-dimensional array of rigid cylinders. Phys Rev Lett 80:5325–5328Sánchez-Pérez JV, Rubio C, Martínez-Sala R, Sánchez-Grandia R, Gómez V (2002) Acoustic barriers based on periodic arrays of scatterers. Appl Phys Lett 27:5240–5242Sanchis L, Hakkansson A, López-Zanón D, Bravo-Abad J, Sánchez-Dehesa J (2004) Integrated optical devices design by genetic algorithm. Appl Phys Lett 84:4460–4462Shen M, Cao W (2001) Acoustic band-gap engineering using finite-size layered structures of multiple periodicity. Appl Phys Lett 75:3713–3715Sigalas M, Economou E (1992) Elastic and acoustic wave band structure. J Sound Vib 158:377Zitzler E (1999) Evolutionary algorithms for multiobjective optimization: Methods and applications. Ph.D. thesis, Swiss Federal Institute of Technology Zuric
    corecore