DSpace Collection: Volume 28 Number 3
http://hdl.handle.net/10525/464
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Reliability for Beta Models
http://hdl.handle.net/10525/504
Title: Reliability for Beta Models<br/><br/>Authors: Nadarajah, Saralees<br/><br/>Abstract: In the area of stress-strength models there has been a largeamount of work as regards estimation of the reliability R = Pr(X2 < X1 )when X1 and X2 are independent random variables belonging to the sameunivariate family of distributions. The algebraic form for R = Pr(X2 < X1 )has been worked out for the majority of the well-known distributions includingNormal, uniform, exponential, gamma, weibull and pareto. However, there are still many other distributions for which the form of R is notknown. We have identified at least some 30 distributions with no knownform for R. In this paper we consider some of these distributions and derivethe corresponding forms for the reliability R. The calculations involve theuse of various special functions.The Automorphism Group of the Free Algebra of Rank Two
http://hdl.handle.net/10525/503
Title: The Automorphism Group of the Free Algebra of Rank Two<br/><br/>Authors: Cohn, P.<br/><br/>Abstract: The theorem of Czerniakiewicz and Makar-Limanov, that allthe automorphisms of a free algebra of rank two are tame is proved here byshowing that the group of these automorphisms is the free product of twogroups (amalgamating their intersection), the group of all affine automorphismsand the group of all triangular automorphisms. The method consistsin finding a bipolar structure. As a consequence every finite subgroup of automorphisms (in characteristic zero) is shown to be conjugate to a group oflinear automorphisms.Groups with Restricted Conjugacy Classes
http://hdl.handle.net/10525/502
Title: Groups with Restricted Conjugacy Classes<br/><br/>Authors: de Giovanni, F.; Russo, A.; Vincenzi, G.<br/><br/>Abstract: Let F C 0 be the class of all finite groups, and for each nonnegative integer n define by induction the group class FC^(n+1) consisting ofall groups G such that for every element x the factor group G/CG ( <x>^G )has the property FC^n . Thus FC^1 -groups are precisely groups with finiteconjugacy classes, and the class FC^n obviously contains all finite groups andall nilpotent groups with class at most n. In this paper the known theoryof FC-groups is taken as a model, and it is shown that many properties ofFC-groups have an analogue in the class of FC^n -groups.On the Stabilization of the Wave Equation by the Boundary
http://hdl.handle.net/10525/501
Title: On the Stabilization of the Wave Equation by the Boundary<br/><br/>Authors: Cardoso, Fernando; Vodev, Georgi<br/><br/>Abstract: We study the distribution of the (complex) eigenvalues for interior boundary value problems with dissipative boundary conditions in thecase of C 1 -smooth boundary under some natural assumption on the behaviourof the geodesics. As a consequence we obtain energy decay estimates ofthe solutions of the corresponding wave equation.<br/><br/>Description: * Partially supported by CNPq (Brazil)On a Class of Vertex Folkman Numbers
http://hdl.handle.net/10525/500
Title: On a Class of Vertex Folkman Numbers<br/><br/>Authors: Nenov, Nedyalko<br/><br/>Abstract: Let a1 , . . . , ar, be positive integers, i=1 ... r, m = ∑(ai − 1) + 1 andp = max{a1 , . . . , ar }. For a graph G the symbol G → (a1 , . . . , ar ) meansthat in every r-coloring of the vertices of G there exists a monochromaticai -clique of color i for some i ∈ {1, . . . , r}. In this paper we consider thevertex Folkman numbersF (a1 , . . . , ar ; m − 1) = min |V (G)| : G → (a1 , . . . , ar ) and Km−1 ⊂ G}We prove that F (a1 , . . . , ar ; m − 1) = m + 6, if p = 3 and m ≧ 6 (Theorem3) and F (a1 , . . . , ar ; m − 1) = m + 7, if p = 4 and m ≧ 6 (Theorem 4).Using Monte Carlo Methods to Evaluate Sub-Optimal Exercise Policies for American Options
http://hdl.handle.net/10525/499
Title: Using Monte Carlo Methods to Evaluate Sub-Optimal Exercise Policies for American Options<br/><br/>Authors: Alobaidi, Ghada; Mallier, Roland<br/><br/>Abstract: In this paper we use a Monte Carlo scheme to find the returnsthat an uninformed investor might expect from an American option if hefollowed one of several näıve exercise strategies rather than the optimalexercise strategy. We consider several such strategies that an ill-advisedinvestor might follow. We also consider how the expected return is affectedby how often the investor checks to see if his exercise criteria have been met.<br/><br/>Description: ∗This research, which was funded by a grant from the Natural Sciences and Engineering Research Council of Canada, formed part of G.A.’s Ph.D. thesis [1].Caractérisation Des Espaces 1-Matriciellement Normés
http://hdl.handle.net/10525/498
Title: Caractérisation Des Espaces 1-Matriciellement Normés<br/><br/>Authors: Le Merdy, Christian; Mezrag, Lahcéne<br/><br/>Abstract: Let X be a closed subspace of B(H) for some Hilbert spaceH. In [9], Pisier introduced Sp [X] (1 ≤ p ≤ +∞) by setting Sp [X] =(S∞ [X] , S1 [X])θ , (where θ =1/p , S∞ [X] = S∞ ⊗min X and S1 [X] = S1 ⊗∧ X) and showed that there are p−matricially normed spaces. In this paper weprove that conversely, if X is a p−matricially normed space with p = 1,then there is an operator structure on X, such that M1,n (X) = S1 [X] whereSn,1 [X] is the finite dimentional version of S1 [X]. For p = 1, we have noanswer.Compositions, Generated by Special Nets in Affinely Connected Spaces
http://hdl.handle.net/10525/497
Title: Compositions, Generated by Special Nets in Affinely Connected Spaces<br/><br/>Authors: Zlatanov, Georgi<br/><br/>Abstract: Special nets which characterize Cartesian, geodesic, Chebyshevian, geodesic-Chebyshevian and Chebyshevian-geodesic compositions are introduced. Con-ditions for the coefficients of the connectedness in the parameters of thesespecial nets are found.