In this paper we calculate the massive particle creation as seen by a stationary observer in a 1 + 1 dimensional spacetime compact in space. The Bogolubov transformation relating the annihilation and creation operators between two spacelike surfaces is calculated. The particle creation, as observed by a stationary observer who moves from the first spacelike surface to the second is then calcula...

Sufficient conditions for monotonic behaviour of relative increment and hazard rate functions h of unimodal distributions of types U and J are being investigated, proved and then applied to some distributions. In addition, a general algorithm for checking monotonic properties of h is given, where we do not need the cumulative distribution function F (x) = x R −∞ f(t)dt. Instead, we use the prob...

We construct the Drinfeld twists (factorizing F -matrices) of the gl(m|n)invariant fermion model. Completely symmetric representation of the pseudoparticle creation operators of the model are obtained in the basis provided by the F -matrix (the F -basis). We resolve the hierarchy of the nested Bethe vectors in the F -basis for the gl(m|n) supersymmetric model.

We compute all string tree level correlation functions of vertex operators in c < 1 string theory. This is done by using the ring structure of the theory. In order to study the multicritical behaviour, we calculate the correlation functions after perturbation by physical vertex operators. We show that the (2k − 1, 2) models can be obtained from the (1, 2) model and the minimal models can be obt...

Cardiac intervention is a minimally invasive diagnostic and therapeutic procedure used to treat cardiac diseases. The mapping of heart geometry with minimal visual assistance presents a technical challenge for interventional cardiologists attempting catheter navigation. This paper presents a geometric approach to modeling the catheter–heart interaction for VR simulations of catheter navigation ...

We consider the determination of the number ck (α) of ordered factorizations of an arbitrary permutation on n symbols, with cycle distribution α, into k-cycles such that the factorizations have minimal length and the group generated by the factors acts transitively on the n symbols. The case k = 2 corresponds to the celebrated result of Hurwitz on the number of topologically distinct holomorphi...

The study of harmonic functions on a locally compact group G has recently been transferred to a “non-commutative” setting in two different directions: C.-H. Chu and A. T.-M. Lau replaced the algebra L∞(G) by the group von Neumann algebra VN(G) and the convolution action of a probability measure μ on L∞(G) by the canonical action of a positive definite function σ on VN(G); on the other hand, W. ...

In this paper we derive conditions on the internal wear process under which the resulting time-to-failure model will be of the simple collapsible form (Oakes, 1995, Duchesne and Lawless, 2000) when the usage accumulation history is available. We suppose that failure occurs when internal wear crosses a certain threshold and/or a traumatic event causes the item to fail (Cox, 1999 and Bagdonavičiu...

Intuitionistic Fuzzy Modal Operator was defined by Atanassov in cite{at3}in 1999. In 2001, cite{at4}, he introduced the generalization of thesemodal operators. After this study, in 2004, Dencheva cite{dencheva} definedsecond extension of these operators. In 2006, the third extension of thesewas defined in cite{at6} by Atanassov. In 2007,cite{gc1}, the authorintroduced a new operator over Intuit...

in this paper we give conditions for a tuple of commutative bounded linear operators which holds in the property of the hypercyclicity criterion. we characterize topological transitivity and semi-hereiditarily of a dynamical system given  by an n-tuple of operators acting on a separable infinite dimensional banach space .