Browsing by Author "Pinto, Alberto A."
Now showing 1 - 10 of 14
Results Per Page
Sort Options
- Anosov and circle diffeomorphismsPublication . Almeida, João P.; Fisher, Albert M.; Pinto, Alberto A.; Rand, David A.We present an infinite dimensional space of C1+ smooth conjugacy classes of circle diffeomorphisms that are C1+ fixed points of renormalization. We exhibit a one-to-one correspondence between these C1+ fixed points of renormalization and C1+ conjugacy classes of Anosov diffeomorphisms.
- Anosov diffeomorphismsPublication . Almeida, João P.; Fisher, Albert M.; Pinto, Alberto A.; Rand, David A.We use Adler, Tresser and Worfolk decomposition of Anosov automorphisms to give an explicit construction of the stable and unstable C^{1+} self-renormalizable sequences
- Anosov Diffeomorphisms and γ -TilingsPublication . Almeida, João P.; Pinto, Alberto A.We consider a toral Anosov automorphism G γ : T γ → T γ given by G γ (x, y) = (ax+ y, x) in the < v, w > base, where a∈ N\ { 1 } , γ= 1 / (a+ 1 / (a+ 1 / …)) , v= (γ, 1) and w= (- 1 , γ) in the canonical base of R 2 and T γ = R 2 / (vZ× wZ). We introduce the notion of γ-tilings to prove the existence of a one-to-one correspondence between (i) marked smooth conjugacy classes of Anosov diffeomorphisms, with invariant measures absolutely continuous with respect to the Lebesgue measure, that are in the isotopy class of G γ ; (ii) affine classes of γ-tilings; and (iii) γ-solenoid functions. Solenoid functions provide a parametrization of the infinite dimensional space of the mathematical objects described in these equivalences.
- Golden tilingsPublication . Pinto, Alberto A.; Almeida, João P.; Portela, A.We introduce the notion of golden tilings and we prove a oneto- one correspondence between (i) smooth conjugacy classes of Anosov diffeomorphisms, with an invariant measure absolutely continuous with respect to the Lebesgue measure, (ii) affine classes of golden tilings and (iii) solenoid functions. The solenoid functions give a parametrization of the infinite dimensional space consisting of the mathematical objects described in the above equivalences.
- Golden tilingsPublication . Almeida, João P.; Pinto, Alberto A.In this talk we present the definition of a golden sequence {ri}i2N. These golden sequences have the property of being Fibonacci quasi-periodic and determine a tiling in the real line. We prove a one-to-one correspondence between: (i) affine classes of golden tilings; (ii) smooth conjugacy classes of Anosov difeomorphisms, with an invariant measure absolutely continuous with respect to the Lebesgue measure, that are topologically conjugate to the Anosov automorphism
- Golden tilingsPublication . Pinto, Alberto A.; Almeida, João P.; Portela, A.A. Pinto and D. Sullivan [3] proved a one-to-one correspondence between: (i) Cl+ conjugacy classes of expanding circle maps; (ii) solenoid functions and (iii) Pinto-Sullivan's dyadic tilings on the real line. Here, we prove a one-to-one correspondence between: (i) golden tilings; (ii) smooth conjugacy classes of golden diffeomorphism of the circle that are fixed points of renormalization; (iii) smooth conjugacy classes of Anosov difeomorphisms, with an invariant measure absolutely continuous with respect to the Lebesgue measure, that are topologically conjugated to the Anosov automorphism G(x, y) = (x + y, x) and (iv) solenoid functions.
- Ladrilhamentos dourados da recta realPublication . Pinto, Alberto A.; Almeida, João P.; Portela, AldoApresentaremos a definição de sucessão dourada {r_i}. Estas sucessões possuem a propriedade de serem Fibonacci quasi-periodicas e determinam um ladrilhamento na recta real. Provaremos uma correspondência bijectiva entre: (i) sucessões douradas; (ii) Classes de conjugação diferenciáveis de difeomorfismos de Anosov na classe de conjugação topológica do automorfismo hiperbólico do toro G(x,y) =(x+y,x); (iii) Classes de conjugação diferenciáveis de difeomorfismos da circunferência com número de rotação igual ao inverso do número de ouro e que são pontos fixos do operador renormalização.
- Local market structure in a hotelling townPublication . Pinto, Alberto A.; Almeida, João P.; Parreira, TelmoWe develop a theoretical framework to study the location-price competition in a Hotelling-type network game, extending the Hotelling model, with linear transportation costs, from a line (city) to a network (town). We show the existence of a pure Nash equilibrium price if, and only if, some ex- plicit conditions on the production costs and on the network structure hold. Furthermore, we prove that the local optimal localization of the firms are at the cross-roads of the town.
- Operational Research IO2017, Valença, Portugal, June 28-30Publication . Vaz, A.I.; Almeida, João P.; Oliveira, José F.; Pinto, Alberto A.This proceedings book presents selected contributions from the XVIII Congress of APDIO (the Portuguese Association of Operational Research) held in Valença on June 28–30, 2017. Prepared by leading Portuguese and international researchers in the field of operations research, it covers a wide range of complex real-world applications of operations research methods using recent theoretical techniques, in order to narrow the gap between academic research and practical applications. Of particular interest are the applications of, nonlinear and mixed-integer programming, data envelopment analysis, clustering techniques, hybrid heuristics, supply chain management, and lot sizing and job scheduling problems. In most chapters, the problems, methods and methodologies described are complemented by supporting figures, tables and algorithms. The XVIII Congress of APDIO marked the 18th installment of the regular biannual meetings of APDIO – the Portuguese Association of Operational Research. The meetings bring together researchers, scholars and practitioners, as well as MSc and PhD students, working in the field of operations research to present and discuss their latest works. The main theme of the latest meeting was Operational Research Pro Bono. Given the breadth of topics covered, the book offers a valuable resource for all researchers, students and practitioners interested in the latest trends in this field.
- PrefacePublication . Almeida, João P.; Relvas, Susana; Oliveira, José F.; Pinto, Alberto A.In 2019, APDIO has organized the twentieth Portuguese national conference of Operational Research (OR)—the IO series. With this long-lasting list of events, success has been the main takeaway from each unique occurrence. With a growing number of members, also with growing enthusiasm, the conference series has reached most regions in themainland country.Recently, the frequency of the conference was increased, while maintaining the same attendance and quality of work. Outreach of the conference to OR researchers from different nationalities is also increasing and bringing an international feel to the events. Year after year, keynote speakers from industry and from other European societies have joined us to share knowledge and current research and practice of OR. Our national OR discussion forum has influenced, as well, a growing number of national members attending and presenting in international OR conferences and participating actively in EURO Working Groups. However, besides validating our OR research, our national conferences always promote a very strong, very Portuguese social occasion. A true networking event is where work and social well-being are sustained—and looked forward—event after event. With this book as the last physical milestone of IO2019, we perpetuate the results from this event and invite all our members,