Neste trabalho apresentamos três métodos distintos provando que S(n) = +1 X k=−1 (4k + 1)−n é um múltiplo racional de n para todos os inteiros n = 1, 2, 3, . . . O primeiro utiliza a teoria das função analíticas e funções geradoras. No segundo reduzimos o problema, via mudança de variável devida a E. Calabi, ao cálculo do volume de certos politopos em Rn enquanto que no terceiro usamos a teoria dos operadores integrais compactos. Cada um dos métodos tem um interesse intrínsico e está sujeito a generalizações para aplicações em novas situações.

Neste trabalho apresentamos três métodos distintos provando que S(n) = +1 X k=−1 (4k + 1)−n é um múltiplo racional de n para todos os inteiros n = 1, 2, 3, . . . O primeiro utiliza a teoria das função analíticas e funções geradoras. No segundo reduzimos o problema, via mudança de variável devida a E. Calabi, ao cálculo do volume de certos politopos em Rn enquanto que no terceiro usamos a teoria dos operadores integrais compactos. Cada um dos métodos tem um interesse intrínsico e está sujeito a generalizações para aplicações em novas situações.

Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Matemática, 2016. / Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2016-09-20T17:02:05Z No. of bitstreams: 1 2016_MartaLizethCalvacheHoyos.pdf: 607395 bytes, checksum: 3bf26cd865a4183a9fc9b160b451a76c (MD5) / Approved for entry into archive by Raquel Viana(raquelviana@bce.unb.br) on 2016-09-30T22:12:44Z (GMT) No. of bitstreams: 1 2016_MartaLizethCalvacheHoyos.pdf: 607395 bytes, checksum: 3bf26cd865a4183a9fc9b160b451a76c (MD5) / Made available in DSpace on 2016-09-30T22:12:44Z (GMT). No. of bitstreams: 1 2016_MartaLizethCalvacheHoyos.pdf: 607395 bytes, checksum: 3bf26cd865a4183a9fc9b160b451a76c (MD5) / Neste trabalho estudamos a convergência em Informação de Fisher relativa, de uma sequência de somas estabilizadas de variáveis aleatórias i.i.d. para uma variável aleatória estável não-extremal, sob a hipótese de convergência em distribuição. ________________________________________________________________________________________________ ABSTRACT / In this work, we studied the convergence to a non-extremal stable variable in Relative Fisher Information for stabilized sums of i.i.d. random variables, under the hypothesis of convergence in distribution.

Neste trabalho apresentamos três métodos distintos provando que S(n) = +1 X k=−1 (4k + 1)−n é um múltiplo racional de n para todos os inteiros n = 1, 2, 3, . . . O primeiro utiliza a teoria das função analíticas e funções geradoras. No segundo reduzimos o problema, via mudança de variável devida a E. Calabi, ao cálculo do volume de certos politopos em Rn enquanto que no terceiro usamos a teoria dos operadores integrais compactos. Cada um dos métodos tem um interesse intrínsico e está sujeito a generalizações para aplicações em novas situações.

<p>This report contains a degree project made by the mechanical engineering students Lennart Andersson and Daniel Jansson. The project has performed in assignment by SOMAS Valves AB in Säffle. SOMAS are leading in development on control and on/off valves. To maintain this position they always want to improve their products. One way in this development is valves that are more tightened.</p><p>The purpose with our project was to investigate another seat design on a HiCo (High Cobalt Alloy) seat to a SKV 150 PN 25 valve and compare this to an original HiCo seat.</p><p>By modifying the seat on a ball valve we want to achieve a valve that leaks lesser then a valve whit original seat. At the same time the maneuver torque should be retained or better and the wear should not be worse.</p><p>The project begins with a theoretic investigation of valve forces, maneuver torque and seat design. A manufacturing drawing was made in Pro ENGINEER and handed over to SOMAS AB for manufacturing. Four seats are made in the new design and will be compared with four original seats about maneuver torque, tightened and wear. The idea to make a trace in the middle of the seat was that it would tighten earlier.</p><p>Water under pressure is pressed against the valve to test its resistance of leaking, the leaking is measured by a measure glass. The modified seats leaks more then the original seats, even though, according to the theory they should have a higher seat force. Even the maneuver torque is higher on the modified seats, but this increase is not a problem. All seats was tested to watch their resistant to wear, to test this, a valve mounted with seats is opened and closed 600 times (about 3hours). Because of the short wear time it’s hard to see and validated wear, but on the after coming pressure test the valve is more tightened.</p><p>A reason to leaking is the tolerances between the seats and the ball. The reason why the modified valve seat leaks more is probably that the lathe area functions as a channel for the medium.</p><p>The medium which passes the first tightened area can easier find a new way to pass the second tightened area.</p><p>The conclusion is that the new seat design is nothing to go further with, but there are proposals for a new seat design.</p>

No description available.

No description available.

This report contains a degree project made by the mechanical engineering students Lennart Andersson and Daniel Jansson. The project has performed in assignment by SOMAS Valves AB in Säffle. SOMAS are leading in development on control and on/off valves. To maintain this position they always want to improve their products. One way in this development is valves that are more tightened. The purpose with our project was to investigate another seat design on a HiCo (High Cobalt Alloy) seat to a SKV 150 PN 25 valve and compare this to an original HiCo seat. By modifying the seat on a ball valve we want to achieve a valve that leaks lesser then a valve whit original seat. At the same time the maneuver torque should be retained or better and the wear should not be worse. The project begins with a theoretic investigation of valve forces, maneuver torque and seat design. A manufacturing drawing was made in Pro ENGINEER and handed over to SOMAS AB for manufacturing. Four seats are made in the new design and will be compared with four original seats about maneuver torque, tightened and wear. The idea to make a trace in the middle of the seat was that it would tighten earlier. Water under pressure is pressed against the valve to test its resistance of leaking, the leaking is measured by a measure glass. The modified seats leaks more then the original seats, even though, according to the theory they should have a higher seat force. Even the maneuver torque is higher on the modified seats, but this increase is not a problem. All seats was tested to watch their resistant to wear, to test this, a valve mounted with seats is opened and closed 600 times (about 3hours). Because of the short wear time it’s hard to see and validated wear, but on the after coming pressure test the valve is more tightened. A reason to leaking is the tolerances between the seats and the ball. The reason why the modified valve seat leaks more is probably that the lathe area functions as a channel for the medium. The medium which passes the first tightened area can easier find a new way to pass the second tightened area. The conclusion is that the new seat design is nothing to go further with, but there are proposals for a new seat design.

Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Matemática, 2009. / Submitted by Jaqueline Ferreira de Souza (jaquefs.braz@gmail.com) on 2010-04-22T11:43:59Z No. of bitstreams: 1 2009_ThiagoGoncalvesDias.pdf: 241739 bytes, checksum: d9bf4924cba0648340d5e1060be50437 (MD5) / Approved for entry into archive by Lucila Saraiva(lucilasaraiva1@gmail.com) on 2010-05-07T21:29:51Z (GMT) No. of bitstreams: 1 2009_ThiagoGoncalvesDias.pdf: 241739 bytes, checksum: d9bf4924cba0648340d5e1060be50437 (MD5) / Made available in DSpace on 2010-05-07T21:29:51Z (GMT). No. of bitstreams: 1 2009_ThiagoGoncalvesDias.pdf: 241739 bytes, checksum: d9bf4924cba0648340d5e1060be50437 (MD5) Previous issue date: 2009-07-09 / Neste trabalho estudamos somas incompletas de caracteres e como estimar estas usando métodos analíticos para relacioná-las com somas completas associadas, para as quais existem métodos de estimação vindos de geometria algébrica. Estabelecemos um método analítico geral para completar somas, e mostramos que o método falha para somas mais curtas que q1/2, que é uma barreira natural. Em seguida mostramos como ultrapassar esta barreira no caso mais clássico, que resulta no Teorema de Burgess. ______________________________________________________________________________ ABSTRACT / In this work we study incomplete character sums and how to estimate these using analytic methods to relate with associated complete sums, for which them exist estimation methods from algebraic geometry. We establish a general analytic method to complete sums, and show that the method fails for sums shorter than q1/2 which is a natural barrier. We then show how to pass this of barrier in the most classical case, which leads to Burgesss Theorem.

Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Exatas, 2015. / Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2015-12-21T13:35:23Z No. of bitstreams: 1 2015_WembesomMendesSoares.pdf: 531592 bytes, checksum: 8e5a84b56c9fa404fbeabc136346a98e (MD5) / Approved for entry into archive by Patrícia Nunes da Silva(patricia@bce.unb.br) on 2016-01-08T11:03:16Z (GMT) No. of bitstreams: 1 2015_WembesomMendesSoares.pdf: 531592 bytes, checksum: 8e5a84b56c9fa404fbeabc136346a98e (MD5) / Made available in DSpace on 2016-01-08T11:03:16Z (GMT). No. of bitstreams: 1 2015_WembesomMendesSoares.pdf: 531592 bytes, checksum: 8e5a84b56c9fa404fbeabc136346a98e (MD5) / Nesta tese, usamos a conexão entre a distância Mallows, d_(F;G), e a convergência em distribuição para estender resultados assintóticos envolvendo somas parciais, mesmo quando d_(F;G) = 1. Para isso, produzimos vários resultados matemáticos envolvendo as distribuições ponderadas e a distância Mallows ponderada, d_;w(F;G). Provamos também a convergência em distância Mallows do processo empírico geral, um tipo particular de somas parciais baseadas numa distribuição empírica Fn, para uma variável aleatória Gaussiana e, por meio do processo quantil empírico, atestamos o mesmo modo de convergência da estatística nd22 ;w(Fn; F) para um funcional ponderado de Pontes Brownianas. ______________________________________________________________________________________________ ABSTRACT / The connection between Mallows distance, d_(F;G), and the convergence in distribution has been sucessfully used to establish asymptotic results for partial sums. We further explore this connection by making use of the weighted Mallows distance, d_;w(F;G), to extend the results for the extreme cases when d_(F;G) = 1. Our results are applied to heavy-tailed partial sums and to partial sums that arise in the context of empirical processes and their related functionals.