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Article Citation - WoS: 62Citation - Scopus: 69Estimation in Coherent Reliability Systems Through Copulas(Elsevier Sci Ltd, 2011) Eryilmaz, SerkanThe problem of estimating the parameter of a common distribution of components' lifetimes from system's lifetime data is of interest and importance in reliability engineering. The present paper deals with this problem when the common component distribution is exponential with mean it and the lifetimes of components have an exchangeable joint distribution which is constructed by the help of Archimedean copula. In particular we obtain moment estimator of p for Clayton and Ali-Mikhail-Haq copulas. We illustrate the findings of the paper for a special class of coherent systems called consecutive k-within-m-out-of-n:F system. A simulation study is performed to investigate the properties of the moment estimator. The method presented in this paper can be applied to all coherent systems. (C) 2010 Elsevier Ltd. All rights reserved.Article Policy Frameworks Without Practice? Exploring Marine Governance and Climate Integration Challenges in Türkiye(Elsevier Sci Ltd, 2026) Karli, AygunThe marine-climate nexus has emerged as a critical frontier in global environmental governance, yet its integration into national policy frameworks remains uneven. This article examines the case of T & uuml;rkiye, a middleincome country with extensive coastlines and increasing exposure to climate risks, to explore how marine and climate governance interact in practice. Drawing on 22 semi-structured interviews with experts from government, civil society, and academia, the study applies thematic analysis to identify six interrelated challenges: (1) the gap between legal frameworks and implementation, (2) crisis-based governance, (3) institutional fragmentation and coordination deficits, (4) dependence on European Union funding and external alignment, (5) societal indifference and limited marine literacy, and (6) the contested discourse of the blue economy. The findings demonstrate that although T & uuml;rkiye has adopted robust legal instruments and aligned with EU standards, enforcement and institutional integration remain weak. Governance is often reactive, fragmented, and externally driven, with limited societal demand for ambitious reforms. These dynamics reflect broader patterns in global marine-climate governance but are compounded by T & uuml;rkiye's context specific political and institutional constraints. The article argues that bridging the persistent policy-practice gap will require stronger institutional coordination, investments in capacity and literacy, and reframing the blue economy as a vehicle for climate adaptation and mitigation rather than narrow economic growth.Article Citation - WoS: 8Citation - Scopus: 10Temperature Effects on Optical Characteristics of Cdse Thin Films(Elsevier Sci Ltd, 2021) Gullu, H. H.; Isik, M.; Surucu, O.; Gasanly, N. M.; Parlak, M.CdSe is one of the significant members of II-VI type semiconducting family and it has a wide range of technological applications in which optoelectronic devices take a special position. The present paper reports the structural and optical characteristics of thermally evaporated CdSe thin films. XRD pattern exhibited preferential orientation along (111) plane while atomic composition analyses resulted in the ratio of Cd/Se as closer to 1.0. Temperature-dependent band gap characteristics of CdSe thin films were investigated for the first time by carrying out transmission experiments in the 10-300 K range. The analyses showed that direct band gap energy of the compound decreases from 1.750 (at 10 K) to 1.705 eV (at 300 K). Varshni model was successfully applied to the temperature-band gap energy dependency and various optical constants were determined. Raman spectrum of CdSe thin films was also presented to understand the vibrational characteristics of the compound. The present paper would provide worthwhile data to researchers especially studying on optoelectronic device applications of CdSe thin films.Article Citation - WoS: 9Citation - Scopus: 9Optical Dynamics in the Ag/Α-ga2< Layer System(Elsevier Sci Ltd, 2018) Alharbi, S. R.; Qasrawi, A. F.In this work, thin films of Ga2S3 are deposited onto 150 nm thick transparent Ag substrate by the physical vapor deposition technique under vacuum pressure of 10(-5) mbar. The films are studied by the X-ray diffraction and optical spectrophotometry techniques. It is found that the Ag substrate induced the formation of the monoclinic alpha-Ga2S3 polycrystals. The transparent Ag substrate also changed the preferred optical transition in Ga2S3 from direct to indirect It also increased the light absorption by 79 and 23 times at incident light energies of 2.01 and 2.48 eV, respectively. In addition, a red shift in all types of optical transitions is observed. Some the extended energy band tails of Ag appears to form interbands in the band gap of Ga2S3. These interbands strongly attenuated the dielectric and optical conduction parameters. Particularly, an enhancement in the dielectric constant values and response to incident electromagnetic field is observed. The Drude-Lorentz modeling of this interface has shown that the free carrier density, drift mobility, plasmon frequency and reduced electron-plasmon frequency in Ga2S3 increases when the Ag substrate replaced the glass or other metals like Yb, Al and Au. The nonlinear optical dynamics of the Ag/Ga2S3 are promising as they indicate the applicability of this interface for optoelectronic applications.Article Citation - WoS: 5Citation - Scopus: 5The Mean Number of Failed Components in Discrete Time Consecutive K-Out F System and Its Application To Parameter Estimation and Optimal Age-Based Preventive Replacement(Elsevier Sci Ltd, 2025) Eryilmaz, Serkan; Kan, CihangirIt is important in many respects to have information about the number of failed components in the system when or before a system fails. This paper investigates the mean number of failed components at or before the failure time of the linear consecutive k-out-of-n:F system which is a useful structure to model various engineering systems such as transportation and transmission systems. In particular, closed form expressions for the mean number of failed components within the system that have discretely distributed components lifetimes are obtained. The results are used to estimate the unknown parameter of the components' lifetime distribution and to find the optimal replacement cycle that minimizes the expected cost per unit of time under a certain age-based replacement policy.Article Citation - WoS: 30Citation - Scopus: 31A New Low-Voltage Polymeric Electrochromic(Elsevier Sci Ltd, 2010) Pamuk, Melek; Tirkes, Seha; Cihaner, Atilla; Algi, FatihDesign, synthesis, and properties of a novel donor-acceptor-donor type low-voltage-driven green polymeric electrochrome, P1, which is based on 8-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-11-(2,3-dihydrothieno[3,4-b][l,4]dioxin-7-yl)acenaphtho[1,2-b]quinoxaline (1) are highlighted. It is noted that P1 has an ambipolar (n- and p-doping processes) character in 0.1 M tetrabutylammonium hexafluorophosphate/dichloromethame solution and switches to a transmissive blue state upon oxidation. Furthermore, this new polymeric electrochromic candidate exhibits high redox stability, high coloration efficiency and/or contrast ratio, high percent transmittance (%T) and low response time (1.0 s) with a band gap of 1.10 eV-1.25 eV. (C) 2009 Elsevier Ltd. All rights reserved.Article Citation - WoS: 9Citation - Scopus: 10Evaluating the Current Situation of Oral and Dental Healthcare Services in Turkey and Recommending Solutions(Elsevier Sci Ltd, 2017) Ekici, Omer; Tengilimoglu, Dilaver; Isik, OguzObjectives: To identify issues with Turkeys oral and dental healthcare services and develop recommendations for their effective resolution. Methods: This study analyzes Turkey's oral and dental healthcare system and its problematic issues and surveys other systems and reform strategies being implemented worldwide. The questionnaire-based field survey asked 560 dentists and 84 managers working in public oral and dental healthcare centers in 12 different regions and 52 central and chamber directors affiliated with the Turkish Dental Association about dental health issues and potential restructuring in dental healthcare in Turkey. The survey comprised four sections that, in addition to gathering participant information, inquired into the current overall condition of the Turkish dental healthcare system, the problems necessitating system restructuring, and recommendations to resolve these problems. Results: Participants agree that there are structural and functional problems in Turkey's dental healthcare system. Although there is an overall consensus in regard to the recommendations for resolving the problems, priorities differ among participant groups. However, participants do agree that preventive services in Turkey are insufficient and require improvement. Conclusions: This study exposed issues in oral and dental healthcare services in Turkey that fall into four categories: management and organization, service delivery, human resources, and financing. Based on the results, we propose a new organization model for oral and dental healthcare in Turkey that is integrated within the healthcare system using a public health approach and that prioritizes preventive healthcare services. (C) 2017 Fellowship of Postgraduate Medicine. Published by Elsevier Ltd. All rights reserved.Article Citation - WoS: 85Citation - Scopus: 104Effects of Cast-In Concrete Topping on Flexural Response of Precast Concrete Hollow-Core Slabs(Elsevier Sci Ltd, 2015) Baran, ErayResults of a study focusing on the flexural response of precast prestressed concrete hollow-core slabs with cast-in-place concrete topping are presented. The experimental part of the study included load testing of five precast concrete hollow-core units. The numerically determined flexural response of test specimens was later compared with the experimentally obtained behavior. Results demonstrate that a major composite action is valid between the hollow-core unit and the topping slab under load levels corresponding to uncracked state of the cross section. Existence of a topping slab resulted in improvements in the cracking moment and initial stiffness of hollow-core units. The beneficial effect of topping slab on the ultimate moment capacity was observed to be limited, mainly because of the loss of composite action prior to reaching the ultimate moment capacity. Horizontal shear strength at the interface between hollow-core unit and topping slab was determined (1) through limited number of pushoff load tests and (2) through calculations considering the load level corresponding to initiation of significant relative slip using the basic mechanics of materials approach and the simplified code expression. The measured and computed interface shear strength values were observed to be significantly lower than the horizontal shear strength values specified by the ACI and AASHTO Specifications. (C) 2015 Elsevier Ltd. All rights reserved.Conference Object Citation - WoS: 1A Platinum-Blue Complex Exerts Its Cytotoxic Activity Via Dna Damage and Induces Apoptosis in Cancer Cells(Elsevier Sci Ltd, 2016) Adiguzel, Z.; Ozalp-Yaman, S.; Celik, G.; Salem, S.; Bagci-Onder, T.; Cetin, Y. C.; Acilan, C.[No Abstract Available]Editorial Citation - WoS: 4Citation - Scopus: 5Discussion of "bearing Capacity of Geocell Reinforcement in Embankment Engineering" by Ling Zhang, Minghua Zhao, Caijun Shi and Heng Zhao 2010,28; 475-482(Elsevier Sci Ltd, 2012) Gurbuz, Ayhan[No Abstract Available]
