Filter Design in Coaxial Cavities

A classical topic in Telecommunication Engineering is filter design at microwave frequencies. It constitutes a complex problem and therefore the whole process is divided into several stages, whose analysis is the general aim of this study. Firstly the approximation problem is addressed by means of the generalised Chebychev method. After a process of finite transmission zeros allocation is carried out, the design polynomials are obtained. They meet the specifications typically given in the frequency domain. From the design polynomials of the preceding stage the synthesis of the coupling matrix is developed. The coupling matrix stores information which can be directly translated into useful equivalent circuits upon which filter design at microwave frequencies is based. Sometimes there are values (i.e. called couplings) that must be annihilated in order to obtain a practical circuit topology. Towards that end matrix rotations are introduced. Regarding physical filter design, this study raises three different approaches. In the context of lowpass filters, a stepped impedance filter is designed in coaxial technology. Both circuital and full-wave optimization are introduced under this scenario. With respect to bandpass filters, several waveguide direct-coupled filters are designed. Their full-wave responses are optimized for the sake of improvement. Finally, in the same scenario of bandpass filter design a further step is taken, and a method based on sequential stages is proposed. It is applied over a combline filter in the S-Band for mobile communications. Budget and time constraints have prevented us from doing the manufacturing process, which could be addresses in the near future.Un escenario típico en Ingeniería de Telecomunicación es el diseño de filtros de radiofrecuencia. Es un problema complejo, por lo que habitualmente se aborda en varias etapas. El análisis de las mismas es el propósito general de este trabajo. En primer lugar se decide resolver el problema de la aproximación por medio del método generalizado de Chebychev. Tras el establecimiento de los pertinentes ceros de transmisión finitos, este método obtiene los polinomios de diseño. La respuesta asociada a dichos polinomios cumple las especificaciones de diseño, típicamente dadas a través de una máscara en el dominio de la frecuencia. En la siguiente etapa de diseño se enmarca la síntesis de la matriz de acoplos. La información numérica que almacena esta matriz se traduce directamente en un equivalente circuital. El diseño de filtros de radiofrecuencia sienta sus bases en la aproximación de estructuras de radiofrecuencia a modelos equivalentes, por lo que la matriz de acoplos se convierte en una herramienta de gran utilidad. Se introduce adicionalmente el concepto de rotación como proceso adicional de eliminación de acoplos. Dicho proceso puede ser requerido para obtener una implementación sencilla en las estructuras típicas de radiofrecuencia. Con respecto a la realización física de filtros, se plantean tres aproximaciones. En el contexto de los filtros paso bajo se diseña un filtro de secciones cortas en coaxial. En este escenario se introducen tanto la optimización circuital como la electromagnética. Con respecto a los filtros paso banda, se diseñan varios filtros de cavidades de acoplos directos. Una vez finalizado su diseño se lleva a cabo un proceso adicional de optimización para mejorar sus prestaciones. Finalmente, en este mismo escenario de aproximaciones paso banda se propone un método basado en subdivisión de etapas. Dicho método se aplica en el diseño de un filtro combline en banda S para comunicaciones móviles. Por limitaciones de tiempo y presupuesto no se ha llevado a cabo la fabricación de ningún prototipo, quedando esta tarea como objetivo a desarrollar en un futuro cercano

Delay Extraction Based Equivalent Elmore Model For RLC On-Chip Interconnects

As feature sizes for VLSI technology is shrinking, associated with higher operating frequency, signal integrity analysis of on-chip interconnects has become a real challenge for circuit designers. For this purpose, computer-aided-design (CAD) tools are necessary to simulate signal propagation of on-chip interconnects which has been an active area for research. Although SPICE models exist which can accurately predict signal degradation of interconnects, they are computationally expensive. As a result, more effective and analytic models for interconnects are required to capture the response at the output of high speed VLSI circuits. This thesis contributes to the development of efficient and closed form solution models for signal integrity analysis of on-chip interconnects. The proposed model uses a delay extraction algorithm to improve the accuracy of two-pole Elmore based models used in the analysis of on-chip distributed RLC interconnects. In the proposed scheme, the time of fight signal delay is extracted without increasing the number of poles or affecting the stability of the transfer function. This algorithm is used for both unit step and ramp inputs. From the delay rational approximation of the transfer function, analytic fitted expressions are obtained for the 50% delay and rise time for unit step input. The proposed algorithm is tested on point to point interconnections and tree structure networks. Numerical examples illustrate improved 50% delay and rise time estimates when compared to traditional Elmore based two-pole models

Multiphysics and Thermodynamic Formulations for Equilibrium and Non-equilibrium Interactions: Non-linear Finite Elements Applied to Multi-coupled Active Materials

[EN] Combining several theories this paper presents a general multiphysics framework applied to the study of coupled and active materials, considering mechanical, electric, magnetic and thermal fields. The framework is based on thermodynamic equilibrium and non-equilibrium interactions, both linked by a two-temperature model. The multi-coupled governing equations are obtained from energy, momentum and entropy balances; the total energy is the sum of thermal, mechanical and electromagnetic parts. The momentum balance considers mechanical plus electromagnetic balances; for the latter the Abraham rep- resentation using the Maxwell stress tensor is formulated. This tensor is manipulated to automatically fulfill the angular momentum balance. The entropy balance is for- mulated using the classical Gibbs equation for equilibrium interactions and non-equilibrium thermodynamics. For the non-linear finite element formulations, this equation requires the transformation of thermoelectric coupling and conductivities into tensorial form. The two-way thermoe- lastic Biot term introduces damping: thermomechanical, pyromagnetic and pyroelectric converse electromagnetic dynamic interactions. Ponderomotrix and electromagnetic forces are also considered. The governing equations are converted into a variational formulation with the resulting four-field, multi-coupled formalism implemented and val- idated with two custom-made finite elements in the research code FEAP. Standard first-order isoparametric eight-node elements with seven degrees of freedom (dof) per node (three displacements, voltage and magnetic scalar potentials plus two temperatures) are used. Non-linearities and dynamics are solved with Newton-Raphson and New- mark-b algorithms, respectively. Results of thermoelectric, thermoelastic, thermomagnetic, piezoelectric, piezomag- netic, pyroelectric, pyromagnetic and galvanomagnetic interactions are presented, including non-linear depen- dency on temperature and some second-order interactions.This research was partially supported by grants CSD2008-00037 Canfranc Underground Physics, Polytechnic University of Valencia under programs PAID 02-11-1828 and 05-10-2674. The first author used the grant Generalitat Valenciana BEST/2014/232 for the completion of this work.Pérez-Aparicio, JL.; Palma, R.; Taylor, R. (2016). Multiphysics and Thermodynamic Formulations for Equilibrium and Non-equilibrium Interactions: Non-linear Finite Elements Applied to Multi-coupled Active Materials. Archives of Computational Methods in Engineering. 23:535-583. https://doi.org/10.1007/s11831-015-9149-9S53558323Abraham M (1910) Sull’elettrodinamica di Minkowski. Rend Circ Mat 30:33–46Allik H, Hughes TJR (1970) Finite elment method for piezoelectric vibration. Int J Numer Methods Eng 2:151–157Antonova EE, Looman DC (2005) Finite elements for thermoelectric device analysis in ANSYS. In: International conference on thermoelectricsAtulasimha J, Flatau AB (2011) A review of magnetostrictive iron–gallium alloys. Smart Mater Struct 20:1–15Ballato A (1995) Piezoelectricity: old effect, new thrusts. IEEE Trans Ultrason Ferroelectr Freq Control 42(5):916–926Baoyuan S, Jiantong W, Jun Z, Min Q (2003) A new model describing physical effects in crystals: the diagrammatic and analytic methods for macro-phenomenological theory. J Mater Process Technol 139:444–447Bargmann S, Steinmann P (2005) Finite element approaches to non-classical heat conduction in solids. Comput Model Eng Sci 9(2):133–150Bargmann S, Steinmann P (2006) Theoretical and computational aspects of non-classical thermoelasticity. Comput Methods Appl Mech Eng 196:516–527Bargmann S, Steinmann P (2008) Modeling and simulation of first and second sound in solids. Int J Solids Struct 45:6067–6073Barnett SM (2010) Resolution of the Abraham–Minkowski dilemma. Phys Rev Lett 104:070401Benbouzid MH, Meunier G, Meunier G (1995) Dynamic modelling of giant magnetostriction in Terfenol-D rods by the finite element method. IEEE Trans Magn 31(3):1821–1824Benbouzid MH, Reyne G, Meunier G (1993) Nonlinear finite element modelling of giant magnetostriction. IEEE Trans Magn 29(6):2467–2469Benbouzid MH, Reyne G, Meunier G (1995) Finite elment modelling of magnetostrictive devices: investigations for the design of the magnetic circuit. IEEE Trans Magn 31(3):1813–1816Besbes M, Ren Z, Razek A (1996) Finite element analysis of magneto-mechanical coupled phenomena in magnetostrictive materials. IEEE Trans Magn 32(3):1058–1061Biot MA (1956) Thermoelasticity and irreversible thermodynamics. J Appl Phys 27(3):240–253Bisio G, Cartesegna M, Rubatto G (2001) Thermodynamic analysis of elastic systems. Energy Convers Manag 42:799–812Blun SL (1974) Materials for radiation detection. National Academy of Sciences, WashingtonBonet J, Wood RD (1997) Nonlinear continuum mechanics for finite element analysis. Cambridge University Press, CambridgeBorovik-Romanov AS (1960) Piezomagnetism in the antiferromagnetic fluorides of cobalt and manganese. Sov Phys 11:786Bowyer P (2005) The momentum of light in media: the Abraham–Minkowski controversy. http://bit.ly/1M7wyATBrauer JR, Ruehl JJ, MacNeal BE, Hirtenfelder F (1995) Finite element analysis of Hall effect and magnetoresistance. IEEE Trans Electron Devices 42(2):328–333Bustamante R, Dorfmann A, Ogden RW (2009) On electric body forces and Maxwell stresses in nonlinearly electroelastic solids. Int J Eng Sci 47:1131–1141Callen HB (1948) The application of Onsager’s reciprocal relations to thermoelectric, thermomagnetic, and galvanomagnetic effects. Phys Rev 73(11):1349–1358Callen HB (1985) Thermodynamics and an introduction to thermostatistics. Wiley, New YorkCarter JP, Booker JR (1989) Finite element analysis of coupled thermoelasticity. Comput Struct 31(1):73–80Cattaneo C (1938) Sulla conduzione del calore. Atti Semin Mat Fis Univ Modena 3:83–1013Chaplik AV (2000) Some exact solutions for the classical Hall effect in an inhomogeneous magnetic field. JETP Lett 72:503Chen PJ, Gurtin ME (1968) On a theory of heat conduction involving two temperatures. J Z Angew Math Phys ZAMP 19(4):614–627Chu LJ, Haus HA, Penfield P (1966) The force density in polarizable and magnetizable fluids. In: Proceedings of the IEEEClin Th, Turenne S, Vasilevskiy D, Masut RA (2009) Numerical simulation of the thermomechanical behavior of extruded bismuth telluride alloy module. J Electron Mater 38(7):994–1001Coleman BD (1964) Thermodynamics of materials with memory. Arch Ration Mech Anal 17:1–46de Groot SR (1961) Non-equilibrium themodynamics of systems in an electromagnetic field. J Nucl Energy C Plasma Phys 2:188–194de Groot SR, Mazur P (1984) Non-equilibrium thermodynamics. Dover, MineolaDebye P (1913) On the theory of anomalous dispersion in the region of long-wave electromagnetic radiation. Verh dtsch phys Ges 15:777–793del Castillo LF, García-Colín LS (1986) Thermodynamic basis for dielectric relaxation in complex materials. Phys Rev B 33(7):4944–4951Delves RT (1964) Figure of merit for Ettingshausen cooling. Br J Appl Phys 15:105–106Dorf RC (1997) The electrical engineering handbook. CRC Press, UKEarle R, Richards JFC (1956) Theophrastus: on stones. Ohio State University, ColumbusEbling D, Jaegle M, Bartel M, Jacquot A, Bottner H (2009) Multiphysics simulation of thermoelectric systems for comparison with experimental device performance. J Electron Mater 38(7):1456–1461El-Karamany AS, Ezzat MA (2011) On the two-temperature Green–Naghdi thermoelasticity theories. J Therm Stress 34:1207–1226Eringen AC (1980) Mechanics of continua. Robert E Krieger, MalabarEringen AC, Maugin GA (1990) Electrodynamics of continua I. Springer, New YorkErsoy Y (1984) A new nonlinear constitutive theory for conducting magnetothermoelastic solids. Int J Eng Sci 22(6):683–705Ersoy Y (1986) A new nonlinear constitutive theory of electric and heat conductions for magnetoelastothermo-electrical anisotropic solids. Int J Eng Sci 24(6):867–882Ferrari A, Mittica A (2013) Thermodynamic formulation of the constitutive equations for solids and fluids. Energy Convers Manag 66:77–86Galushko D, Ermakov N, Karpovski M, Palevski A, Ishay JS, Bergman DJ (2005) Electrical, thermoelectric and thermophysical properties of hornet cuticle. Semicond Sci Technol 20:286–289Gao JL, Du QG, Zhang XD, Jiang XQ (2011) Thermal stress analysis and structure parameter selection for a Bi2Te3-based thermoelectric module. J Electron Mater 40(5):884–888Gaudenzi P, Bathe KJ (1995) An iterative finite element procedure for the analysis of piezoelectric continua. J Intell Mater Syst Struct 6:266–273Gavela D, Pérez-Aparicio JL (1998) Peltier pellet analysis with a coupled, non-linear 3D finite element model. In: 4th European workshop on thermoelectricsGoudreau GL, Taylor RL (1972) Evaluation of numerical integration methods in elastodynamics. Comput Methods Appl Mech Eng 2:69–97Griffiths DJ (1999) Introduction to electrodynamics. Prentice-Hall Inc, Upper Saddle RiverGros L, Reyne G, Body C, Meunier G (1998) Strong coupling magneto mechanical methods applied to model heavy magnetostrictive actuators. IEEE Trans Magn 34(5):3150–3153Gurtin ME, Williams WO (1966) On the Clausius–Duhem inequality. J Z Angew Math Phys ZAMP 17(5):626–633Hamader VM, Patil TA, Chovan SH (1987) Free vibration response of two-dimensional magneto-electro-elastic laminated plates. Build Mater Sci 9:249–253Hausler C, Milde G, Balke H, Bahr HA, Gerlach G (2001) 3-D modeling of pyroelectric sensor arrays part I: multiphysics finite-element simulation. IEEE Sens J 8(12):2080–2087He Y (2004) Heat capacity, thermal conductivity and thermal expansion of barium titanate-based ceramics. Thermochimica 419:135–141Hernández-Lemus E, Orgaz E (2002) Hysteresis in nonequilibrium steady states: the role of dissipative couplings. Rev Mex Fís 48:38–45Hinds EA (2009) Momentum exchange between light and a single atom: Abraham or Minkowski? Phys Rev Lett 102:050403Hirsinger L, Billardon R (1995) Magneto-elastic finite element analysis including magnetic forces and magnetostriction effects. IEEE Trans Magn 31(3):1877–1880Huang MJ, Chou PK, Lin MC (2008) An investigation of the thermal stresses induced in a thin-film thermoelectric cooler. J Therm Stress 31:438–454IEEE Standards Board (1988) IEEE standard on piezoelectricity. ANSI/IEEE Std 176-1987. doi: 10.1109/IEEESTD.1988.79638IEEE Standards Board (1991) IEEE standard on magnetostrictive materials: piezomagnetic nomenclature. IEEE Std 319-1990. doi: 10.1109/IEEESTD.1991.101048Ioffe Institute (2013) INSb—indium antimonide. Ioffe Institute. www.ioffe.rssi.ru/SVA/NSM/Semicond/InSb/index.htmlJackson JD (1962) Classical electrodynamics. Wiley, New YorkJaegle M (2008) Multiphysics simulation of thermoelectric systems—modeling of Peltier—cooling and thermoelectric generation. In: Proceedings of the COMSOLJaegle M, Bartel M, Ebling D, Jacquot A, Bottner H (2008) Multiphysics simulation of thermoelectric systems. In: European conference on thermoelectrics ECT2008Jiménez JL, Campos I (1996) Advanced electromagnetism: foundations, theory and applications, chapter The balance equations of energy and momentum in classical electrodynamics. World Scientific Publishing, SingaporeJohnstone S (2008) Is there potential for use of the Hall effect in analytical science? Analyst 133:293–296Jou D, Lebon G (1996) Extended irreversible thermodynamics. Springer, BerlinKaltenbacher M, Kaltenbacher B, Hegewald T, Lerch R (2010) Finite element formulation for ferroelectric hysteresis of piezoelectric materials. J Intell Mater Syst Struct 21:773–785Kaltenbacher M, Meiler M, Ertl M (2009) Physical modeling and numerical computation of magnetostriction. Int J Comput Math Electr Electron Eng 28(4):819–832Kamlah M, Bohle U (2001) Finite element analysis of piezoceramic components taking into account ferroelectric hysteresis behavior. Int J Solids Struct 38:605–633Kannan KS, Dasgupta A (1997) A nonlinear Galerkin finite-element theory for modeling magnetostrictive smart structures. Smart Mater Struct 6:341–350Kiang J, Tong L (2010) Nonlinear magneto-mechanical finite element analysis of Ni–Mn–Ga single crystals. Smart Mater Struct 19:1–17Kinsler P, Favaro A, McCall MW (2009) Four Poynting theorems. Eur J Phys 30:983–993Klinckel S, Linnemann K (2008) A phenomenological constitutive model for magnetostrictive materials and ferroelectric ceramics. Proc Appl Math Mech 8:10507–10508Kosmeier D (2013) Hornets: Gentle Giants! Wikipedia: the free encyclopedia. www.hornissenschutz.de/hornets.htmLahmer T (2008) Forward and inverse problems in piezoelectricity. PhD thesis, Universität Erlangen-NürnbergLandau LD, Lifshitz EM (1982) Mechanics. Butterworth-Heinemann, OxfordLandau LD, Lifshitz EM (1984) Electrodynamics of continuous media. Pergamon Press, OxfordLandis CM (2002) A new finite-element formulation for electromechanical boundary value problems. Int J Numer Methods Eng 55:613–628Díaz Lantada A (2011) Handbook of active materials for medical devices: advances and applications. CRC Press, Boca RatonLebon G, Jou D, Casas-Vázquez J (2008) Understanding non-equilibrium thermodynamics. Springer, BerlinLinnemann K, Klinkel S (2006) A constitutive model for magnetostrictive materials—theory and finite element implementation. Proc Appl Math Mech 6:393–394Linnemann K, Klinkel S, Wagner W (2009) A constitutive model for magnetostrictive and piezoelectric materials. Int J Solids Struct 46:1149–1166Llebot JE, Jou D, Casas-Vázquez J (1983) A thermodynamic approach to heat and electric conduction in solids. Physica 121(A):552–562Lu X, Hanagud V (2004) Extended irreversible thermodynamics modeling for self-heating and dissipation in piezoelectric ceramics. IEEE Trans Ultrason Ferroelectr Freq Control 51(12):1582–1592Lubarda VA (2004) On thermodynamic potentials in linear thermoelasticity. Int J Solids Struct 41:7377–7398Mansuripur M (2012) Trouble with the lorentz law of force: incompatibility with special relativity and momentum conservation. Phys Rev Lett 108:193901Maruszewski B, Lebon G (1986) An extended irreversible thermodynamic description of electrothermoelastic semiconductors. Int J Eng Sci 24(4):583–593McMeeking RM, Landis CM (2005) Electrostatic forces and stored energy for deformable dielectric materials. J Appl Mech 72:581–590McMeeking RM, Landis CM, Jimenez MA (2007) A principle of virtual work for combined electrostatic and mechanical loading of materials. Int J Non Linear Mech 42:831–838MELCOR (2000) Thermoelectric handbook. Melcor, a unit of Laird Technologies. http://www.lairdtech.comMinkowski H (1908) Nachr. ges. wiss. Gottingen 53Naranjo B, Gimzewski JK, Putterman S (2005) Observation of nuclear fusion driven by a pyroelectric crystal. Nature 28(434):1115–1117Nédélec JC (1980) Mixed finite elements in $${R}^3$$ R 3 . Numer Math 35:314–345Nettleton RE, Sobolev SL (1995) Applications of extended thermodynamics to chemical, rheological, and transport processes: a special survey part I. approaches and scalar rate processes. J Non-Equilib Thermodyn 20:205–229Nettleton RE, Sobolev SL (1995) Applications of extended thermodynamics to chemical, rheological, and transport processes: a special survey part II. vector transport processes, shear relaxation and rheology. J Non-Equilib Thermodyn 20:297–331Nettleton RE, Sobolev SL (1996) Applications of extended thermodynamics to chemical, rheological, and transport processes: a special survey part III. wave phenomena. J Non-Equilib Thermodyn 21:1–16Newmark N (1959) A method of computation for structural dynamics. ASCE J Eng Mech 85:67–94Newnham RE (2005) Properties of materials: anisotropy, symmetry, structure. Oxford University Press, OxfordNour AE, Abd-Alla N, Maugin GA (1990) Nonlinear equations for thermoelastic magnetizable conductors. Int J Eng Sci 27(7):589–603Nowacki A (1962) International series of monographs in aeronautics and astronautics. Pergamon Press, OxfordOkumura H, Hasegawa Y, Nakamura H, Yamaguchi S (1999) A computational model of thermoelectric and thermomagnetic semiconductors. In: 18th international conference on thermoelectricsOkumura H, Yamaguchi S, Nakamura H, Ikeda K, Sawada K (1998) Numerical computation of thermoelectric and thermomagnetic effects. In: 17th international conference on thermoelectricsOliver X, Agelet C (2000) Continuum mechanics for engineers. Edicions UPC, Barcelona. http://hdl.handle.net/2099.3/36197Shankar K, Kondaiah P, Ganesan N (2013) Pyroelectric and pyromagnetic effects on multiphase magneto-electro-elastic cylindrical shells for axisymmetric temperature. Smart Mater Struct 22(2):025007Palma R, Pérez-Aparicio JL, Bravo R (2013) Study of hysteretic thermoelectric behavior in photovoltaic materials using the finite element method, extended thermodynamics and inverse problems. Energy Convers Manag 65:557–563Palma R, Pérez-Aparicio JL, Taylor RL (2012) Non-linear finite element formulation applied to thermoelectric materials under hyperbolic heat conduction model. Comput Method Appl Mech Eng 213–216:93–103Palma R, Rus G, Gallego R (2009) Probabilistic inverse problem and system uncertainties for damage detection in piezoelectrics. Mech Mater 41:1000–1016Pérez-Aparicio JL, Gavela D (1998) 3D, non-linear coupled, finite element model of thermoelectricity. In: 4th European workshop on thermoelectricsPérez-Aparicio JL, Palma R, Taylor RL (2012) Finite element analysis and material sensitivity of Peltier thermoelectric cells coolers. Int J Heat Mass Transf 55:1363–1374Pérez-Aparicio JL, Sosa H (2004) A continuum three-dimensional, fully coupled, dynamic, non-linear finite element formulation for magnetostrictive materials. Smart Mater Struct 13:493–502Perez-Aparicio JL, Sosa H, Palma R (2007) Numerical investigations of field-defect interactions in piezoelectric ceramics. Int J Solids Struct 44:4892–4908Pérez-Aparicio JL, Taylor RL, Gavela D (2007) Finite element analysis of nonlinear fully coupled thermoelectric materials. Comput Mech 40:35–45Qi H, Fang D, Yao Z (1997) FEM analysis of electro-mechanical coupling effect of piezoelectric materials. Comput Mater Sci 8:283–290Pérez-Aparicio JL, Palma R, Abouali-Sánchez S (2014) Complete finite element method analysis of galvanomagnetic and thermomagnetic effects. Appl Therm Eng (submitted)Perez-Aparicio JL, Palma R, Moreno-Navarro P (2014) Elasto-thermoelectric non-linear, fully coupled, and dynamic finite element analysis of pulsed thermoelectrics. Appl Therm Eng (submitted)Ramírez F, Heyliger PR, Pan E (2006) Free vibration response of two-dimensional magneto-electro-elastic laminated plates. J Sound Vib 292:626–644Reitz JR, Milford FJ (1960) Foundations of electromagnetic theory. Addison-Wesley, BostonReng Z, Ionescu B, Besbes M, Razek A (1995) Calculation of mechanical deformation of magnetic materials in electromagnetic devices. IEEE Trans Magn 31(3):1873–1876Restuccia L (2010) On a thermodynamic theory for magnetic relaxation phenomena due to n microscopic phenomena described by n internal variables. J Non-Equilib Thermodyn 35:379–413Restuccia L, Kluitenberg GA (1988) On generalizations of the Debye equation for dielectric relaxation. Phys A 154:157–182Restuccia L, Kluitenberg GA (1992) On the heat dissipation function for dielectric relaxation phenomena in anisotropic media. Int J Eng Sci 30(3):305–315Riffat SB, Ma X (2003) Thermoelectrics: a review of present and potential applications. Appl Therm Eng 23:913–935Rinaldi C, Brenner H (2002) Body versus surface forces in continuum mechanics: is the Maxwell stress tensor a physically objective Cauchy stress? Phys Rev E 65:036615Rowe DM (ed) (1995) CRC handbook of thermoelectrics. CRC Press, UKRus G, Palma R, Pérez-Aparicio JL (2009) Optimal measurement setup for damage detection in piezoelectric plates. Int J Eng Sci 47:554–572Rus G, Palma R, Pérez-Aparicio JL (2012) Experimental design of dynamic model-based damage identification in piezoelectric ceramics. Mech Syst Signal Process 26:268–293Sadiku MNO (2001) Numerical techniques in electromagnetics. CRC Press LLC, Boca RatonSemenov AS, Kessler H, Liskowsky A, Balke H (2006) On a vector potential formulation for 3D electromechanical finite element analysis. Commun Numer Methods Eng 22:357–375Serra E, Bonaldi M (2008) A finite element formulation for thermoelastic damping analysis. Int J Numer Methods Eng 78(6):671–691Several. Wikipedia. Wikipedia: The Free Encyclopedia, SeveralSoh AK, Liu JX (2005) On the constitutive equations of magnetoelectroelastic solids. J Intell Mater Syst Struct 16:597–602Stefanescu DM (2011) Handbook of force transducers: principles and components. Springer, BerlinTamma KK, Namburu RR (1992) An effective finite element modeling/analysis approach for dynamic thermoelasticity due to second sound effects. Comput Mech 9:73–84Tang T, Yu W (2009) Micromechanical modeling of the multiphysical behavior of smart materials using the variational asymptotic method. Smart Mater Struct 18:1–14Taylor RL (2010) FEAP a finite element analysis program: user manual. University of California, Berkeley. http://www.ce.berkeley.edu/feapThurston RN (1994) Warren p. Mason (1900–1986) physicist, engineer, inventor, author, teacher. IEEE Trans Ultrason Ferroelectr Freq Control 41(4):425–434Tian X, Shen Y, Chen C, He T (2006) A direct finite element method study of generalized thermoelastic problems. Int J Solids Struct 43:2050–2063Tinder RF (2008) Tensor properties of solids: phenomenological development of the tensor properties of crystals. Morgan and Claypool, San RafaelTruesdell C (1968) Thermodynamics for beginners, in irreversible aspects of continuum mechanics. Springer, BerlinTzou HS, Ye R (1996) Pyroelectric and thermal strain effects of piezoelectric (PVDF and PZT) devices. Mech Syst Signal Process 10(4):459–469Walser R (1972) Application of pyromagnetic phenomena to radiation detection

Study of hysteretic thermoelectric behavior in photovoltaic materials using the finite element method, extended thermodynamics and inverse problems

The main objective of the present work is to develop and prove a theoretical explanation based on the Extended Non-Equilibrium Thermodynamics (ENETs) for the hysteretical thermoelectric behavior observed in certain thin-film photovoltaic materials. The ENET introduces dissipative fluxes in the entropy balance that could explain this behavior. To verify this explanation from a numerical point of view, results are generated using a Finite Element (FE) formulation based on the ENET and already developed in previous publications by the authors. In addition, an identification Inverse Problem (IP) is formulated; a cost function is defined as the quadratic difference between experimental and numerical results and the IP is solved minimizing the cost function using genetic algorithms. The conclusion is that the loop-like distributions are due to energy dissipation introduced by dissipative fluxes that are closely related with relaxation times. Also, the FE-IP combination permits to find an approximated characterization of properties for several materials from single experimental curves. Finally, several numerical simulations are proposed for laboratory experiments to further validate the theoretical interpretation and to confirm the relation between relaxation times and hysteresis.This research was partially supported by the Grants CSD2008-00037 Canfranc Underground Physics, Excelencia Junta Andalucia P08-TEP-03641 and Polytechnic University of Valencia under programs PAID 02-11-1828 and 05-10-2674.Palma, R.; Pérez-Aparicio, JL.; Bravo, R. (2013). Study of hysteretic thermoelectric behavior in photovoltaic materials using the finite element method, extended thermodynamics and inverse problems. Energy Conversion and Management. 65(92):557-563. https://doi.org/10.1016/j.enconman.2012.07.009S557563659

Physics-based multiscale coupling for full core nuclear reactor simulation

Numerical simulation of nuclear reactors is a key technology in the quest for improvements in efficiency, safety, and reliability of both existing and future reactor designs. Historically, simulation of an entire reactor was accomplished by linking together multiple existing codes that each simulated a subset of the relevant multiphysics phenomena. Recent advances in the MOOSE (Multiphysics Object Oriented Simulation Environment) framework have enabled a new approach: multiple domain-specific applications, all built on the same software framework, are efficiently linked to create a cohesive application. This is accomplished with a flexible coupling capability that allows for a variety of different data exchanges to occur simultaneously on high performance parallel computational hardware. Examples based on the KAIST-3A benchmark core, as well as a simplified Westinghouse AP-1000 configuration, demonstrate the power of this new framework for tackling—in a coupled, multiscale manner—crucial reactor phenomena such as CRUD-induced power shift and fuel shuffle.Massachusetts Institute of Technology. Department of Nuclear Science and EngineeringIdaho National Laboratory (Contract DE-AC07-05ID14517

Reconstruction of phase dynamics from macroscopic observations based on linear and nonlinear response theories

We propose a method to reconstruct the phase dynamics in rhythmical interacting systems from macroscopic responses to weak inputs by developing linear and nonlinear response theories, which predict the responses in a given system. By solving an inverse problem, the method infers an unknown system: the natural frequency distribution, the coupling function, and the time delay which is inevitable in real systems. In contrast to previous methods, our method requires neither strong invasiveness nor microscopic observations. We demonstrate that the method reconstructs two phase systems from observed responses accurately. The qualitative methodological advantages demonstrated by our quantitative numerical examinations suggest its broad applicability in various fields, including brain systems, which are often observed through macroscopic signals such as electroencephalograms and functional magnetic response imaging

Characterization and modeling of a coaxial cavity quadruplet based filter for mobile phone LTE-2 band

En aquest projecte es tracta la caracterització i modelatge d'un filtre de cavitats mitjançant el simulador electromagnètic 3D HFSS. Partint de les especificacions d'un filtre real de telefonia es realitzarà una caracterització completa, modelat i extracció del diagrama nodal ideal. Per a aconseguir-ho, prèviament s'estudiarà el tipus de responsa a aconseguir i es caracteritzarà amb polinomis. Amb l'enfocament de la matriu d'acoblament, primer un conjunt de característiques dels paràmetres S són creats. Seguidament es defineix una topologia del filtre adecuada i finalment la corresponent matriu d'acoblament és sintetitzada. Aquesta matriu d'acoblament defineix tot el filtre, i amb això el corresponent filtre físic pot ser dissenyat i fabricat. Per tancar l'intèrval entre la representació de la matriu d'acoblament d'un filtre i el filtre físic, es dónen uns mètodes per mesurar/calcular els acoblaments i el Q extern. Aquests paràmetres poden ser determinats amb l'ús d'un simulador EM 3D com l'utilitzat en aquest projecte, HFSS.En este proyecto se trata la caracterización y modelado de un filtro de cavidad mediante el simulador electromagnético 3D HFSS. Partiendo de las especificaciones de un filtro real de telefonía se realizará una caracterización completa, modelado y extracción de diagrama nodal ideal. Para ello previamente se estudiará el tipo de respuesta a conseguir y se caracterizará con polinomios. Con el enfoque de la matriz de acoplo, primero un conjunto de características de los parámetros S son creadas. Seguidamente se define una topología del filtro adecuada y finalmente la correspondiente matriz de acoplo es sintetizada. Esta matriz de acoplo define del todo al filtro, y con esto el correspondiente filtro físico puede ser diseñado y fabricado. Para cerrar el intervalo entre la representación de la matriz de acoplo de un filtro y el filtro físico, se dan unos métodos para medir/calcular los acoplos y el Q externo. Estos parámetros pueden ser determinados con el uso de un simulador EM 3D como el utilizado en este proyecto, HFSS.In this project the characterization of a cavity filter by 3D electromagnetic simulator HFSS is proposed. Based on the specifications of a real cellular filter complete characterization, modeling and ideal nodal diagram extraction will be performed. To do so, previously the kind of response to achieve will be studied and characterized with polynomials. With the coupling matrix synthesis approach, a set of filter S-parameter characteristics is first created. Then a suitable filter topology is defined and finally the corresponding coupling matrix is synthesized. This coupling matrix fully defines the filter and, with this at hand, the corresponding physical filter can be designed and manufactured. To close the gap between the coupling matrix representation of a filter and the physical filter, practical directions about how to measure/calculate coupling bandwidths and external Q are given. These parameters can be determined by use of 3D EM simulator as the one used in this project, HFSS