The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform
Juha Honkala - One of the best experts on this subject based on the ideXlab platform.
-
A characterization of rational D0L Power Series
Acta Informatica, 2010Co-Authors: Juha HonkalaAbstract:We study D0L Power Series over an arbitrary field. We characterize those D0L Power Series which are also rational Series. As a consequence we show that rationality is decidable for D0L Power Series over many fields.
-
On images of D0L and DT0L Power Series
Theoretical Computer Science, 2003Co-Authors: Juha HonkalaAbstract:The D0L and DT0L Power Series are generalizations of D0L and DT0L languages. We continue the study of these Series by investigating various decidability questions concerning the images of D0L and DT0L Power Series.
-
On DOL Power Series
Theoretical Computer Science, 2000Co-Authors: Juha HonkalaAbstract:Abstract We study D0L Power Series. We show how elementary morphisms introduced by Ehrenfeucht and Rozenberg can be used in connection with Power Series, characterize the sequences of rational numbers and integers which can appear as coefficients in D0L Power Series and establish various decidability results.
-
The Equivalence Problem of D0L and DF0L Power Series
Fundamenta Informaticae, 1999Co-Authors: Juha HonkalaAbstract:We show that it is decidable whether or not a given D0L Power Series and a given DF0L Power Series over a computable field are equal. This generalizes to Power Series the result of Ruohonen stating that DF0L-D0L language equivalence is decidable.
-
On Sequences Defined by D0L Power Series
Theoretical Informatics and Applications, 1999Co-Authors: Juha HonkalaAbstract:We study D0L Power Series over commutative semirings. We show that a sequence (c n ) n≤0 of nonzero elements of a field A is the coefficient sequence of a D0L Power Series if and only if there exist a positive integer k and integers β i for 1 ≤ i ≤ k such that c n+k = c β1 n+k-1 c β2 n+k-2 … c n βk for all n > 0. As a consequence we solve the equivalence problem of D0L Power Series over computable fields.
Ali Akbar Jafari - One of the best experts on this subject based on the ideXlab platform.
-
Exponentiated Extended Weibull-Power Series class of Distributions
Ciência e Natura, 2015Co-Authors: Saeid Tahmasebi, Ali Akbar JafariAbstract:In this paper, we introduce a new class of distributions by compounding the exponentiated extended Weibull family and Power Series family. This distribution contains several lifetime models such as the complementary extended Weibull-Power Series, generalized exponential-Power Series, generalized linear failure rate-Power Series, exponentiated Weibull-Power Series, generalized modified Weibull-Power Series, generalized Gompertz-Power Series and exponentiated extended Weibull distributions as special cases. We obtain several properties of this new class of distributions such as Shannon entropy, mean residual life, hazard rate function, quantiles and moments. Sub-models of this distribution are studied in details, and the maximum likelihood estimation procedure via a EM-algorithm is presented.
-
Exponentiated Extended Weibull-Power Series Class of Distributions
arXiv: Other Statistics, 2015Co-Authors: Saeid Tahmasebi, Ali Akbar JafariAbstract:In this paper, we introduce a new class of distributions by compounding the exponentiated extended Weibull family and Power Series family. This distribution contains several lifetime models such as the complementary extended Weibull-Power Series, generalized exponential-Power Series, generalized linear failure rate-Power Series, exponentiated Weibull-Power Series, generalized modified Weibull-Power Series, generalized Gompertz-Power Series and exponentiated extended Weibull distributions as special cases. We obtain several properties of this new class of distributions such as Shannon entropy, mean residual life, hazard rate function, quantiles and moments. The maximum likelihood estimation procedure via a EM-algorithm is presented.
Shital R. Patel - One of the best experts on this subject based on the ideXlab platform.
-
Fréchet algebras of Power Series
Banach Center Publications, 2010Co-Authors: H. Garth Dales, Shital R. Patel, Charles John ReadAbstract:We consider Fréchet algebras which are subalgebras of the algebra F=C[[X]] of formal Power Series in one variable and of Fn=C[[X1,…,Xn]] of formal Power Series in n variables, where n∈N. In each case, these algebras are taken with the topology of coordinatewise convergence. We begin with some basic definitions about Fréchet algebras, (F)-algebras, and other topological algebras, and recall some of their properties; we discuss Michael's problem from 1952 on the continuity of characters on these algebras and some results on uniqueness of topology. A `test algebra' U for Michael's problem for commutative Fréchet algebras has been described by Clayton and by Dixon and Esterle. We prove that there is an embedding of U into F, and so there is a Fréchet algebra of Power Series which is a test case for Michael's problem. We also discuss homomorphisms from Fréchet algebras into F. We prove that such a homomorphism is either continuous or a surjection, so answering a question of Dales and McClure from 1977. As corollaries, we note that a subalgebra A of F containing C[X] that is a Banach algebra is already a Banach algebra of Power Series, in the sense that the embedding of A into F is automatically continuous, and that each (F)-algebra of Power Series has a unique (F)-algebra topology. We also prove that it is not true that results analogous to the above hold when we replace F by F2
-
On Fréchet algebras of Power Series
Bulletin of The Australian Mathematical Society, 2002Co-Authors: S. J. Bhatt, Shital R. PatelAbstract:We consider Frechet algebras which are subalgebras of the algebra F=C[[X]] of formal Power Series in one variable and of Fn=C[[X1,…,Xn]] of formal Power Series in n variables, where n∈N. In each case, these algebras are taken with the topology of coordinatewise convergence. We begin with some basic definitions about Frechet algebras, (F)-algebras, and other topological algebras, and recall some of their properties; we discuss Michael's problem from 1952 on the continuity of characters on these algebras and some results on uniqueness of topology. A `test algebra' U for Michael's problem for commutative Frechet algebras has been described by Clayton and by Dixon and Esterle. We prove that there is an embedding of U into F, and so there is a Frechet algebra of Power Series which is a test case for Michael's problem. We also discuss homomorphisms from Frechet algebras into F. We prove that such a homomorphism is either continuous or a surjection, so answering a question of Dales and McClure from 1977. As corollaries, we note that a subalgebra A of F containing C[X] that is a Banach algebra is already a Banach algebra of Power Series, in the sense that the embedding of A into F is automatically continuous, and that each (F)-algebra of Power Series has a unique (F)-algebra topology. We also prove that it is not true that results analogous to the above hold when we replace F by F2.
Saeid Tahmasebi - One of the best experts on this subject based on the ideXlab platform.
-
Exponentiated Extended Weibull-Power Series class of Distributions
Ciência e Natura, 2015Co-Authors: Saeid Tahmasebi, Ali Akbar JafariAbstract:In this paper, we introduce a new class of distributions by compounding the exponentiated extended Weibull family and Power Series family. This distribution contains several lifetime models such as the complementary extended Weibull-Power Series, generalized exponential-Power Series, generalized linear failure rate-Power Series, exponentiated Weibull-Power Series, generalized modified Weibull-Power Series, generalized Gompertz-Power Series and exponentiated extended Weibull distributions as special cases. We obtain several properties of this new class of distributions such as Shannon entropy, mean residual life, hazard rate function, quantiles and moments. Sub-models of this distribution are studied in details, and the maximum likelihood estimation procedure via a EM-algorithm is presented.
-
Exponentiated Extended Weibull-Power Series Class of Distributions
arXiv: Other Statistics, 2015Co-Authors: Saeid Tahmasebi, Ali Akbar JafariAbstract:In this paper, we introduce a new class of distributions by compounding the exponentiated extended Weibull family and Power Series family. This distribution contains several lifetime models such as the complementary extended Weibull-Power Series, generalized exponential-Power Series, generalized linear failure rate-Power Series, exponentiated Weibull-Power Series, generalized modified Weibull-Power Series, generalized Gompertz-Power Series and exponentiated extended Weibull distributions as special cases. We obtain several properties of this new class of distributions such as Shannon entropy, mean residual life, hazard rate function, quantiles and moments. The maximum likelihood estimation procedure via a EM-algorithm is presented.
Charles John Read - One of the best experts on this subject based on the ideXlab platform.
-
Fréchet algebras of Power Series
Banach Center Publications, 2010Co-Authors: H. Garth Dales, Shital R. Patel, Charles John ReadAbstract:We consider Fréchet algebras which are subalgebras of the algebra F=C[[X]] of formal Power Series in one variable and of Fn=C[[X1,…,Xn]] of formal Power Series in n variables, where n∈N. In each case, these algebras are taken with the topology of coordinatewise convergence. We begin with some basic definitions about Fréchet algebras, (F)-algebras, and other topological algebras, and recall some of their properties; we discuss Michael's problem from 1952 on the continuity of characters on these algebras and some results on uniqueness of topology. A `test algebra' U for Michael's problem for commutative Fréchet algebras has been described by Clayton and by Dixon and Esterle. We prove that there is an embedding of U into F, and so there is a Fréchet algebra of Power Series which is a test case for Michael's problem. We also discuss homomorphisms from Fréchet algebras into F. We prove that such a homomorphism is either continuous or a surjection, so answering a question of Dales and McClure from 1977. As corollaries, we note that a subalgebra A of F containing C[X] that is a Banach algebra is already a Banach algebra of Power Series, in the sense that the embedding of A into F is automatically continuous, and that each (F)-algebra of Power Series has a unique (F)-algebra topology. We also prove that it is not true that results analogous to the above hold when we replace F by F2