WoS
Permanent URI for this collectionhttps://hdl.handle.net/20.500.14411/18
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Article Citation - WoS: 105Citation - Scopus: 116(α<i>,</I>ψ)-meir-keeler Contraction Mappings in Generalized <i>b</I>-metric Spaces(Hindawi Ltd, 2018) Karapinar, Erdal; Czerwik, Stefan; Aydi, HassenWe present a fixed point theorem for generalized (alpha, Psi)-Meir-Keeler type contractions in the setting of generalized b-metric spaces. The presented results improve, generalize, and unify many existing famous results in the corresponding literature.Article Citation - WoS: 31Citation - Scopus: 34Development of Decision Support Model for Selecting a Maintenance Plan Using a Fuzzy Mcdm Approach: a Theoretical Framework(Hindawi Ltd, 2018-11-01) Abdulgader, Fathia Sghayer; Eid, Rajeh; Rouyendegh (B Erdebilli), Babak Daneshvar; Rouyendegh , Babak DaneshvarIn complex decision making, using multicriteria decision-making (MCDM) methodologies is the most scientific way to ensure an informed and justified decision between several alternatives. MCDMs have been used in different ways and with several applications that proved their efficiency in achieving this goal. In this research, the advantages and disadvantages of the different MCDM methodologies are studied, along with the different techniques implemented to increase their accuracy and precision. The main aim of the study is to develop a hybrid MCDM process that combines the strengths of several MCDM methods and apply it to choose the best fit maintenance policy/strategy for industrial application. Moreover, fuzzy linguistic terms are utilized in all of the used MCDM techniques in order to eliminate the uncertainty and ambiguity of the results. Through an extensive literature review performed on studies that have used MCDM methods in a hybrid context and using fuzzy linguistic terms, a model is developed to use fuzzy DEMATEL-AHP-TOPSIS hybrid technique. The model with its application is the first of its kind, which combines the strengths of fuzzy DEMATEL in establishing interrelationships between several criteria, as well as performing a pairwise comparison between the criteria for prioritization using the fuzzy AHP method. Thereafter, the alternatives are compared using fuzzy TOPSIS method by establishing negative and positive solutions and calculating the relative closeness for each of the alternatives. Furthermore, six main criteria, twenty criteria, and five alternatives are selected from the literature for the model application.Article Citation - WoS: 27Citation - Scopus: 35Security Awareness Level of Smartphone Users: an Exploratory Case Study(Hindawi Ltd, 2019-05-13) Koyuncu, Murat; Pusatli, TolgaAs smartphone technology becomes more and more mature, its usage extends beyond and covers also applications that require security. However, since smartphones can contain valuable information, they normally become the target of attackers. A physically lost or a hacked smartphone may cause catastrophic results for its owner. To prevent such undesired events, smartphone users should be aware of existing threats and countermeasures to be taken against them. Therefore, user awareness is a critical factor for smartphone security. This study investigates the awareness level of smartphone users for different security-related parameters and compares the awareness levels of different user groups categorized according to their demographic data. It is based on a survey study conducted on a population with a different range of age, education level, and IT security expertise. According to the obtained results, in general, the awareness level of participants is fairly low, which needs considerable improvement. In terms of age, the oldest group has the lowest level followed by the youngest group. Education level, in general, has a positive effect on the awareness level. Having knowledge about IT is another factor increasing the security awareness level of smartphone users.Article Citation - WoS: 20Citation - Scopus: 48Some Common Fixed Point Theorems in Partial Metric Spaces(Hindawi Ltd, 2011-01) Karapinar, Erdal; Yuksel, Ugur; Karapnar, ErdalMany problems in pure and applied mathematics reduce to a problem of common fixed point of some self-mapping operators which are defined on metric spaces. One of the generalizations of metric spaces is the partial metric space in which self-distance of points need not to be zero but the property of symmetric and modified version of triangle inequality is satisfied. In this paper, some well-known results on common fixed point are investigated and generalized to the class of partial metric spaces.Article Citation - WoS: 8Citation - Scopus: 9Life Behavior of a System Under Discrete Shock Model(Hindawi Ltd, 2012-01) Eryilmaz, SerkanWe study the life behavior of a system which is subjected to shocks of random magnitudes over discrete time periods. We obtain the survival function and mean time to failure of the system assuming that the sizes of the shocks follow a discrete probability distribution under cumulative and mixed shock models.Article Citation - WoS: 9Citation - Scopus: 9Fixed Point Theorems for Various Classes of Cyclic Mappings(Hindawi Ltd, 2012-01) Aydi, Hassen; Karapinar, Erdal; Samet, BessemWe introduce new classes of cyclic mappings and we study the existence and uniqueness of fixed points for such mappings. The presented theorems generalize and improve several existing results in the literature.Article Citation - WoS: 10Citation - Scopus: 16Cyclic Contractions on <i>g</I>-metric Spaces(Hindawi Ltd, 2012-01) Karapinar, E.; Yildiz-Ulus, A.; Erhan, I. M.Conditions for existence and uniqueness of fixed points of two types of cyclic contractions defined on G-metric spaces are established and some illustrative examples are given. In addition, cyclic maps satisfying integral type contractive conditions are presented as applications.Article Citation - WoS: 12Citation - Scopus: 15Some Fixed Point Results in <i>gp</I>-metric Spaces(Hindawi Ltd, 2012-01) Aydi, Hassen; Karapinar, Erdal; Salimi, Peyman; Karapnar, ErdalFollowing a recent paper of Zand and Nezhad (2011), we establish some fixed point results in GP-metric spaces. The presented theorems generalize and improve several existing results in the literature. Also, some examples are presented.Article Citation - WoS: 1Citation - Scopus: 2The Functional-Analytic Properties of the Limit <i>q</I>-bernstein Operator(Hindawi Ltd, 2012) Ostrovska, SofiyaThe limit q-Bernstein operator B-q, 0 < q < 1, emerges naturally as a modification of the Szasz-Mirakyan operator related to the Euler distribution. The latter is used in the q-boson theory to describe the energy distribution in a q-analogue of the coherent state. Lately, the limit q-Bernstein operator has been widely under scrutiny, and it has been shown that B-q is a positive shape-preserving linear operator on C[0, 1] with parallel to B-q parallel to = 1. Its approximation properties, probabilistic interpretation, eigenstructure, and impact on the smoothness of a function have been examined. In this paper, the functional-analytic properties of B-q are studied. Our main result states that there exists an infinite-dimensional subspace M of C[0, 1] such that the restriction B-q vertical bar(M) is an isomorphic embedding. Also we show that each such subspace M contains an isomorphic copy of the Banach space c(0).Article Citation - WoS: 15Citation - Scopus: 19Use of Uhpc in Bridge Structures: Material Modeling and Design(Hindawi Ltd, 2012) Gunes, Oguz; Yesilmen, Seda; Gunes, Burcu; Ulm, Franz-JosephUltra-high-performance concrete (UHPC) is a promising new class of concrete material that is likely to make a significant contribution to addressing the challenges associated with the load capacity, durability, sustainability, economy, and environmental impact of concrete bridge infrastructures. This paper focuses on the material modeling of UHPC and design of bridge girders made of UHPC. A two-phase model used for modeling the behavior of UHPC was briefly discussed, and the model was implemented in a preliminary design case study. Based on the implemented design and the reported use of UHPC in bridge applications, the advantages, limitations, and future prospects of UHPC bridges were discussed, highlighting the need for innovative research and design to make optimum use of the favorable properties of the material in bridge structures.