Departament de Matemàtiques
http://hdl.handle.net/2117/3917
Sun, 19 Nov 2017 14:12:20 GMT
20171119T14:12:20Z

Características de la siniestralidad laboral del sector minero español de productos de cantera y rocas ornamentales en los períodos 20032008 y 20092014
http://hdl.handle.net/2117/110822
Características de la siniestralidad laboral del sector minero español de productos de cantera y rocas ornamentales en los períodos 20032008 y 20092014
Sanmiquel Pera, Lluís; Bascompta Massanes, Marc; Anticoi Sudzuki, Hernán Francisco; Rossell Garriga, Josep Maria; Freijo Álvarez, Modesto
Fri, 17 Nov 2017 10:40:55 GMT
http://hdl.handle.net/2117/110822
20171117T10:40:55Z
Sanmiquel Pera, Lluís
Bascompta Massanes, Marc
Anticoi Sudzuki, Hernán Francisco
Rossell Garriga, Josep Maria
Freijo Álvarez, Modesto

Características de la siniestralidad laboral del sector minero español de productos de cantera y rocas ornamentales en los períodos 20032008 y 20092014
http://hdl.handle.net/2117/110821
Características de la siniestralidad laboral del sector minero español de productos de cantera y rocas ornamentales en los períodos 20032008 y 20092014
Sanmiquel Pera, Lluís; Bascompta Massanes, Marc; Anticoi Sudzuki, Hernán Francisco; Rossell Garriga, Josep Maria; Freijo Álvarez, Modesto
Fri, 17 Nov 2017 10:34:15 GMT
http://hdl.handle.net/2117/110821
20171117T10:34:15Z
Sanmiquel Pera, Lluís
Bascompta Massanes, Marc
Anticoi Sudzuki, Hernán Francisco
Rossell Garriga, Josep Maria
Freijo Álvarez, Modesto

Monomial codes seen as invariant subspaces
http://hdl.handle.net/2117/110655
Monomial codes seen as invariant subspaces
García Planas, María Isabel; Magret Planas, Maria dels Dolors; Um, Laurence Emilie
It is well known that cyclic codes are very useful because of their applications, since they are not computationally expensive and encoding can be easily implemented. The relationship between cyclic codes and invariant subspaces is also well known. In this paper a generalization of this relationship is presented between monomial codes over a finite field ¿ and hyperinvariant subspaces of ¿n under an appropriate linear transformation. Using techniques of Linear Algebra it is possible to deduce certain properties for this particular type of codes, generalizing known results on cyclic codes.
Wed, 15 Nov 2017 09:51:08 GMT
http://hdl.handle.net/2117/110655
20171115T09:51:08Z
García Planas, María Isabel
Magret Planas, Maria dels Dolors
Um, Laurence Emilie
It is well known that cyclic codes are very useful because of their applications, since they are not computationally expensive and encoding can be easily implemented. The relationship between cyclic codes and invariant subspaces is also well known. In this paper a generalization of this relationship is presented between monomial codes over a finite field ¿ and hyperinvariant subspaces of ¿n under an appropriate linear transformation. Using techniques of Linear Algebra it is possible to deduce certain properties for this particular type of codes, generalizing known results on cyclic codes.

Ejectioncollision orbits in the Restricted threebody problem
http://hdl.handle.net/2117/110642
Ejectioncollision orbits in the Restricted threebody problem
Ollé Torner, Mercè; Rodríguez del Río, Óscar; Soler Villanueva, Jaume
In this paper we analyse the ejectioncollision (EC) orbits of the planar restricted three body problem. Being µ¿¿¿(0, 0.5] the mass parameter, and taking the big (small) primary with mass (µ), an EC orbit will be an orbit that ejects from the big primary, does an excursion and collides with it. As it is well known, for any value of the mass parameter µ¿¿¿(0, 0.5] and sufficiently restricted Hill regions (that is, for big enough values of the Jacobi constant C), there are exactly four EC orbits. We check their existence and extend numerically these four orbits for µ¿¿¿(0, 0.5] and for smaller values of the Jacobi constant. We introduce the concept of nejectioncollision orbits (nEC orbits) and we explore them numerically for µ¿¿¿(0, 0.5] and values of the Jacobi constant such that the Hill bounded possible region of motion contains the big primary and does not contain the small one. We study the cases 1¿=¿n¿=¿10 and we analyse the continuation of families of such nEC orbits, varying the energy, as well as the bifurcations that appear.
Wed, 15 Nov 2017 09:03:54 GMT
http://hdl.handle.net/2117/110642
20171115T09:03:54Z
Ollé Torner, Mercè
Rodríguez del Río, Óscar
Soler Villanueva, Jaume
In this paper we analyse the ejectioncollision (EC) orbits of the planar restricted three body problem. Being µ¿¿¿(0, 0.5] the mass parameter, and taking the big (small) primary with mass (µ), an EC orbit will be an orbit that ejects from the big primary, does an excursion and collides with it. As it is well known, for any value of the mass parameter µ¿¿¿(0, 0.5] and sufficiently restricted Hill regions (that is, for big enough values of the Jacobi constant C), there are exactly four EC orbits. We check their existence and extend numerically these four orbits for µ¿¿¿(0, 0.5] and for smaller values of the Jacobi constant. We introduce the concept of nejectioncollision orbits (nEC orbits) and we explore them numerically for µ¿¿¿(0, 0.5] and values of the Jacobi constant such that the Hill bounded possible region of motion contains the big primary and does not contain the small one. We study the cases 1¿=¿n¿=¿10 and we analyse the continuation of families of such nEC orbits, varying the energy, as well as the bifurcations that appear.

Combined heat and power using high temperature proton exchange membrane fuel cells for comfort applications
http://hdl.handle.net/2117/110267
Combined heat and power using high temperature proton exchange membrane fuel cells for comfort applications
Sanz i López, Víctor; Costa Castelló, Ramon; Batlle Arnau, Carles
Global concerns about nowadays’ energy shortage problems as well as climate change eects have encouraged alternatives to classical energy sources such as fossil fuels and nuclear power plants. In this context, combined heat and power is presented as a useful option due to its ability of generating both electrical and thermal energy more eciently than conventional methods. Regarding this, high temperature proton exchange membrane fuel cells are not only a reliable way of implementing combined heat and power systems, but also a better solution in terms of energy conversion eciency and greenhouse gases emissions reduction. Therefore, high temperature proton exchange membrane fuel cells are being installed around the world and policies encouraging its utilisation are being promoted.
Fri, 10 Nov 2017 13:00:50 GMT
http://hdl.handle.net/2117/110267
20171110T13:00:50Z
Sanz i López, Víctor
Costa Castelló, Ramon
Batlle Arnau, Carles
Global concerns about nowadays’ energy shortage problems as well as climate change eects have encouraged alternatives to classical energy sources such as fossil fuels and nuclear power plants. In this context, combined heat and power is presented as a useful option due to its ability of generating both electrical and thermal energy more eciently than conventional methods. Regarding this, high temperature proton exchange membrane fuel cells are not only a reliable way of implementing combined heat and power systems, but also a better solution in terms of energy conversion eciency and greenhouse gases emissions reduction. Therefore, high temperature proton exchange membrane fuel cells are being installed around the world and policies encouraging its utilisation are being promoted.

Linear hamiltonian control systems. An approach under linear algebra point of view
http://hdl.handle.net/2117/110146
Linear hamiltonian control systems. An approach under linear algebra point of view
García Planas, María Isabel; Chanes Espigares, Antonio
Hamiltonian systems model a number of important problems in theoretical physics, mechanics, fluid dynamics and others disciplines. Many important physical and engineering processes can be described by a suitable linear Hamiltonian formalism. The properties of Hamiltonian systems like conservation of energy or volume in the phase space leads specific dynamical features. This paper approaches the study, analysis and characterization of linear Hamiltonian systems through the linear algebra
Wed, 08 Nov 2017 12:33:28 GMT
http://hdl.handle.net/2117/110146
20171108T12:33:28Z
García Planas, María Isabel
Chanes Espigares, Antonio
Hamiltonian systems model a number of important problems in theoretical physics, mechanics, fluid dynamics and others disciplines. Many important physical and engineering processes can be described by a suitable linear Hamiltonian formalism. The properties of Hamiltonian systems like conservation of energy or volume in the phase space leads specific dynamical features. This paper approaches the study, analysis and characterization of linear Hamiltonian systems through the linear algebra

Enumeration of labeled 4regular planar graphs
http://hdl.handle.net/2117/109823
Enumeration of labeled 4regular planar graphs
Noy Serrano, Marcos; Requile, Clement; Rué Perna, Juan José
In this extended abstract, we present the first combinatorial scheme for counting labeled 4regular planar graphs through a complete recursive decomposition. More precisely, we show that the exponential generating function counting labeled 4regular planar graphs can be computed effectively as the solution of a system of equations. From here we can extract the coefficients by means of algebraic calculus. As a byproduct, we can also compute the algebraic generating function counting labeled 3connected 4regular planar maps.
© <year>. This manuscript version is made available under the CCBYNCND 4.0 license http://creativecommons.org/licenses/byncnd/4.0/
Mon, 06 Nov 2017 09:02:10 GMT
http://hdl.handle.net/2117/109823
20171106T09:02:10Z
Noy Serrano, Marcos
Requile, Clement
Rué Perna, Juan José
In this extended abstract, we present the first combinatorial scheme for counting labeled 4regular planar graphs through a complete recursive decomposition. More precisely, we show that the exponential generating function counting labeled 4regular planar graphs can be computed effectively as the solution of a system of equations. From here we can extract the coefficients by means of algebraic calculus. As a byproduct, we can also compute the algebraic generating function counting labeled 3connected 4regular planar maps.

Iterative Learning Control for homing guidance design of missiles
http://hdl.handle.net/2117/109686
Iterative Learning Control for homing guidance design of missiles
Acho Zuppa, Leonardo
This paper presents an Iterative Learning Control design applied to homing guidance of missiles against maneuvering targets. According to numerical experiments, although an increase of the control energies is appreciated with respect to a previous published base controller for comparison, this strategy, which is simple to realize, is able to reduce the time to reach the headon condition to target destruction. This fact is important to minimize the missile lateral forcelevel to fulfill engaging in hypersonic target persecutions.
Fri, 03 Nov 2017 07:23:47 GMT
http://hdl.handle.net/2117/109686
20171103T07:23:47Z
Acho Zuppa, Leonardo
This paper presents an Iterative Learning Control design applied to homing guidance of missiles against maneuvering targets. According to numerical experiments, although an increase of the control energies is appreciated with respect to a previous published base controller for comparison, this strategy, which is simple to realize, is able to reduce the time to reach the headon condition to target destruction. This fact is important to minimize the missile lateral forcelevel to fulfill engaging in hypersonic target persecutions.

Estimation of synaptic conductance in the spiking regime for the McKean neuron model
http://hdl.handle.net/2117/109448
Estimation of synaptic conductance in the spiking regime for the McKean neuron model
Guillamon Grabolosa, Antoni; Prohens Sastre, Rafel; Teruel Aguilar, Antonio E.; Vich Llompart, Catalina
In this work, we aim at giving a first proof of concept to address the estimation of synaptic conductances when a neuron is spiking, a complex inverse nonlinear problem which is an open challenge in neuroscience. Our approach is based on a simplified model of neuronal activity, namely, a piecewise linear version of the FitzHughNagumo model. This simplified model allows precise knowledge of the nonlinear fI curve by using standard techniques of nonsmooth dynamical systems. In the regular firing regime of the neuron model, we obtain an approximation of the period which, in addition, improves previous approximations given in the literature to date. By knowing both this expression of the period and the current applied to the neuron, and then solving an inverse problem with a unique solution, we are able to estimate the steady synaptic conductance of the cell's oscillatory activity. Moreover, the method gives also good estimations when the synaptic conductance varies slowly in time.
Tue, 31 Oct 2017 10:59:15 GMT
http://hdl.handle.net/2117/109448
20171031T10:59:15Z
Guillamon Grabolosa, Antoni
Prohens Sastre, Rafel
Teruel Aguilar, Antonio E.
Vich Llompart, Catalina
In this work, we aim at giving a first proof of concept to address the estimation of synaptic conductances when a neuron is spiking, a complex inverse nonlinear problem which is an open challenge in neuroscience. Our approach is based on a simplified model of neuronal activity, namely, a piecewise linear version of the FitzHughNagumo model. This simplified model allows precise knowledge of the nonlinear fI curve by using standard techniques of nonsmooth dynamical systems. In the regular firing regime of the neuron model, we obtain an approximation of the period which, in addition, improves previous approximations given in the literature to date. By knowing both this expression of the period and the current applied to the neuron, and then solving an inverse problem with a unique solution, we are able to estimate the steady synaptic conductance of the cell's oscillatory activity. Moreover, the method gives also good estimations when the synaptic conductance varies slowly in time.

A family of stacked central configurations in the planar fivebody problem
http://hdl.handle.net/2117/109271
A family of stacked central configurations in the planar fivebody problem
Lino Cornelio, J.; Alvarez Ramírez, Martha; Cors Iglesias, Josep Maria
We study planar central configurations of the fivebody problem where three bodies, (Formula presented.) and (Formula presented.), are collinear and ordered from left to right, while the other two, (Formula presented.) and (Formula presented.), are placed symmetrically with respect to the line containing the three collinear bodies. We prove that when the collinear bodies form an Euler central configuration of the threebody problem with (Formula presented.), there exists a new family, missed by Gidea and Llibre (Celest Mech Dyn Astron 106:89–107, 2010), of stacked fivebody central configuration where the segments (Formula presented.) and (Formula presented.) do not intersect.
The final publication is available at link.springer.com via http://dx.doi.org/10.1007/s1056901797828
Thu, 26 Oct 2017 14:36:11 GMT
http://hdl.handle.net/2117/109271
20171026T14:36:11Z
Lino Cornelio, J.
Alvarez Ramírez, Martha
Cors Iglesias, Josep Maria
We study planar central configurations of the fivebody problem where three bodies, (Formula presented.) and (Formula presented.), are collinear and ordered from left to right, while the other two, (Formula presented.) and (Formula presented.), are placed symmetrically with respect to the line containing the three collinear bodies. We prove that when the collinear bodies form an Euler central configuration of the threebody problem with (Formula presented.), there exists a new family, missed by Gidea and Llibre (Celest Mech Dyn Astron 106:89–107, 2010), of stacked fivebody central configuration where the segments (Formula presented.) and (Formula presented.) do not intersect.