A dynamic random environment usually induces statistical dependence among components of a system operating in such an environment thereby making explicit computation of the system performance measures very difficult and possibly even intractable. The multivariate phase-type distribution is a powerful tool for unifying a variety of stochastic models and for constructing new models that yield to ...

Ethynyl-substituted acyclic anion receptors were synthesized for discrete covalently linked and metal-bridged dimers, which form various anionic complexes including double helical structures as the first examples of Cl(-)-bridged [2+2]-type complexes that are stable in the solution state.

The adequate modeling of correlated input processes is an important step in building simulation models. Modeling independent identically distributed data is well established in simulation whereas the integration of correlation is still a challenge. In this paper, ARTA processes which have been used several times for describing correlated input processes in simulation are extended by using ARMA ...

We address the inference of discrete-state models for tree-structured data. Our aim is to introduce parametric multitype branching processes that can be efficiently estimated on the basis of data of limited size. Each generation distribution within this macroscopic model is modeled by a partially directed acyclic graphical model. The estimation of each graphical model relies on a greedy algorit...

The characterization and the canonical representation of order-n phase type distributions (PH(n)) is an open research problem. This problem is solved for n = 2, since the equivalence of the acyclic and the general PH distributions has been proven for a long time. However, no canonical representations have been introduced for the general PH distribution class so far for n > 2. In this paper we s...

Inspired by previous work of Diaz, Petit, Serna, and Trevisan (Approximating layout problems on random graphs Discrete Mathematics, 235, 2001, 245–253), we show that several well-known graph layout problems are approximable to within a factor arbitrarily close to 1 of the optimal with high probability for random graphs drawn from an ErdösRenyi distribution with appropriate sparsity conditions. ...

In this paper we study a broad class of semi-Markovian queues introduced by Sengupta. This class contains many classical queues such as the GI/M/1 queue, SM/MAP/1 queue and others, as well as queues with correlated inter-arrival and service times. Queues belonging to this class are characterized by a set of matrices of size m and Sengupta showed that its waiting time distribution can be represe...

in this paper, nickel oxide (nio) nanoparticles have been prepared by solid state thermal decomposition of an acyclic nickel(ii) complex (1,2-bis(2-formyl-3-methoxyphenyl)propane)nickel(ii) chloride, [nil]cl2, in an electrical furnace at optimal temperature, 450 ºc for 3.5 h. the nickel(ii) complex is obtained via solid state synthesis using nickel(ii) chloride and tetradentate o4 acyclic ligan...