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Article Citation - WoS: 22Citation - Scopus: 23On Residual Lifetime of Coherent Systems After the rth Failure(Springer, 2013) Eryilmaz, SerkanIn this article we study the residual lifetime of a coherent system after the rth failure, i.e. the time elapsed from the rth failure until the system failure given that the system operates at the time of the rth failure. We provide a mixture representation for the corresponding residual lifetime distribution in terms of signature. We also obtain some stochastic ordering results for the residual lifetimes.Article Citation - WoS: 27Citation - Scopus: 30The Distributions of Sum, Minima and Maxima of Generalized Geometric Random Variables(Springer, 2015) Tank, Fatih; Eryilmaz, SerkanGeometric distribution of order as one of the generalization of well known geometric distribution is the distribution of the number of trials until the first consecutive successes in Bernoulli trials with success probability . In this paper, it is shown that this generalized distribution can be represented as a discrete phase-type distribution. Using this representation along with closure properties of phase-type distributions, the distributions of sum, minima and maxima of two independent random variables having geometric distribution of order are obtained. Numerical results are presented to illustrate the computational details.Article Citation - WoS: 13Citation - Scopus: 14Improved Global Robust Stability for Interval-Delayed Hopfield Neural Networks(Springer, 2008) Singh, VimalA modified form of a recent criterion for the global robust stability of interval-delayed Hopfield neural networks is presented. The effectiveness of the modified criterion is demonstrated with the help of an example.Article Citation - WoS: 5Citation - Scopus: 7On the Classification of Modulation Schemes Using Higher Order Statistics and Support Vector Machines(Springer, 2022) Coruk, Remziye Busra; Gokdogan, Bengisu Yalcinkaya; Benzaghta, Mohamed; Kara, AliThe recognition of modulation schemes in military and civilian applications is a major task for intelligent receiving systems. Various Automatic Modulation Classification (AMC) algorithms have been developed for this purpose in the literature. However, classification with low computational complexity as well as reasonable processing time is still a challenge. In this paper, a feature-based approach along with various classifiers is employed based on statistical features as well as higher-order moments and cumulants. An over-the-air (OTA) recorded dataset consisting of four analog and ten digital modulation schemes are used for testing the proposed method at 0-20 dB SNR. The overall accuracy for quadratic Support Vector Machine (SVM) is found to be as high as 98% at 10 dB. The comparison of the results with other AMC papers published in the literature indicates that the proposed method present higher accuracy, especially for realistic channel induced OTA dataset.Article Citation - WoS: 2Citation - Scopus: 2Birman-Hilden Property of Covering Spaces for Nonorientable Surfaces(Springer, 2020) Atalan, F.; Medetogullari, E.Let p : (N) over tilde -> N be a finite covering space for nonorientable surfaces, where chi((N) over tilde) < 0. We study whether or not p has the Birman-Hilden property.Article Citation - WoS: 20Citation - Scopus: 15Assessment of Shock Models for a Particular Class of Intershock Time Distributions(Springer, 2022) Kus, Coskun; Tuncel, Altan; Eryilmaz, SerkanIn this paper, delta and extreme shock models and a mixed shock model which combines delta-shock and extreme shock models are studied. In particular, the interarrival times between successive shocks are assumed to belong to a class of matrix-exponential distributions which is larger than the class of phase-type distributions. The Laplace -Stieltjes transforms of the systems' lifetimes are obtained in a matrix form. Survival functions of the systems are approximated based on the Laplace-Stieltjes transforms. The results are applied for the reliability evaluation of a certain repairable system consisting of two components.Article Citation - WoS: 1Citation - Scopus: 1An Empirical Analysis of the Average Plant Start-Up Size in Turkish Manufacturing Industries(Springer, 2012) Cilasun, Seyit Mumin; Gunalp, BurakMany studies have found start-up size of a firm to be an important determinant of its subsequent performance and probability of survival. The aim of this study is to investigate the determinants of average plant start-up size in 51 four-digit Turkish manufacturing industries for the period 1993-1999. The results of the study suggest that while industry characteristics such as industry growth rate and capital intensity have a positive impact on the average plant start-up size, industrial concentration, import penetration, and the change in research and development expenditures are negatively associated with the same variable. In addition, the macroeconomic environment is also an important determinant of the choice of plant start-up size. Finally, we find evidence that may indicate 'following' (herd) behavior in Turkish manufacturing industries.Article Citation - WoS: 5Citation - Scopus: 5Automorphisms of the mapping class group of a nonorientable surface(Springer, 2017) Atalan, Ferihe; Szepietowski, BlazejLet S be a nonorientable surface of genus g >= 5 with n >= 0 punctures, and Mod(S) its mapping class group. We define the complexity of S to be the maximum rank of a free abelian subgroup of Mod(S). Suppose that S-1 and S-2 are two such surfaces of the same complexity. We prove that every isomorphism Mod(S-1) -> Mod(S-2) is induced by a diffeomorphism S-1 -> S-2. This is an analogue of Ivanov's theorem on automorphisms of the mapping class groups of an orientable surface, and also an extension and improvement of the first author's previous result.Editorial Special Issue: International Workshop in Applied Probability 2014(Springer, 2016) Eryilmaz, S.; Koutras, Markos V.[No Abstract Available]Article Citation - WoS: 48Citation - Scopus: 52Life Behavior of -Shock Models for Uniformly Distributed Interarrival Times(Springer, 2014) Eryilmaz, Serkan; Bayramoglu, KonulIn this paper we study the life behavior of -shock models when the shocks occur according to a renewal process whose interarrival distribution is uniform. In particular, we obtain the first two moments of the corresponding lifetime random variables for general interarrival distribution, and survival functions when the interarrival distribution is uniform.
