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Article Robust Divergence-Based Tests of Hypotheses for Simple Step-Stress Accelerated Life-Testing Under Gamma Lifetime Distributions(Elsevier B.V., 2026) Balakrishnan, N.; Jaenada, M.; Pardo, L.Many modern devices are highly reliable, with long lifetimes before their failure. Conducting reliability tests under actual use conditions may require therefore impractically long experimental times to gather sufficient data for developing accurate inference. To address this, Accelerated Life Tests (ALTs) are often used in industrial experiments to induce product degradation and eventual failure more quickly by increasing certain environmental stress factors. Data collected under such increased stress conditions are analyzed, and results are then extrapolated to normal operating conditions. These tests typically involve a small number of devices and so pose significant challenges, such as interval-censoring. As a result, the outcomes are particularly sensitive to outliers in the data. Additionally, a comprehensive analysis requires more than just point estimation; inferential methods such as confidence intervals and hypothesis testing are essential to fully assess the reliability behaviour of the product. This paper presents robust statistical methods based on minimum divergence estimators for analyzing ALT data of highly reliable devices under step-stress conditions and Gamma lifetime distributions. Robust test statistics generalizing the Rao test and divergence-based tests for testing linear null hypothesis are then developed. These hypotheses include in particular tests for the significance of the identified stress factors and for the validity of the assumption of exponential lifetimes. © 2026Article Citation - WoS: 11Citation - Scopus: 11Supply chain resilience in the tourism and hospitality industry: A comprehensive examination of driving and restraining forces(Elsevier Sci Ltd, 2024) Erol, Ismail; Oztel, Ahmet; Dogru, Tarik; Peker, Iskender; Neuhofer, Irem Onder; Benli, TolgaSupply chain disruptions and a lack of resilient supply chains have adverse impact on the global economy. Particularly, complex nature of the tourism and hospitality industry makes it even more susceptible to failure when supply chain resiliency is rather low or does not exist. However, despite its significance, a comprehensive and systematic examination of building resilience in tourism and hospitality supply chains (THSCs) is lacking in the extant literature. The purpose of this study is to develop a comprehensive framework that outlines the driving and restraining forces for building resilient THSCs. The decision framework proposed in this study integrates rough interval valued neutrosophic (RIVN) force field theory of change with RIVN-ISM-MICMAC methodology. The results showed that the restraining forces, such as lack of effective regulations and incentives and effective organizational and supply chain policies are the primary factors that constrain improving resilience in THSCs. Theoretical and practical implications are discussed.Article Legalizing Anti-Gender Ideology and Civil Society Resistance in Turkey(Elsevier Ltd, 2026) Keysan, A.This study investigates how feminist, LGBTQI+, labour, and human rights organisations in Turkey frame and negotiate the legal institutionalisation of anti-gender ideology and how these processes generate strategic yet fragile cross-movement alliances. Drawing on Benford and Snow's framing theory and Yuval-Davis's transversal politics, the analysis is based on semi-structured interviews conducted with activists from ten organisations between April and June 2025 and organisational documents. The study conceptualises anti-gender politics in Turkey not as a societal backlash but as a state-driven, multi-layered project of “masculinist entrenchment ( Yetiş & Özdüzen, 2024 )” that restructures legal, ideological, and affective arenas. The findings demonstrate that activists increasingly reframe anti-gender assaults as systemic attacks on democracy, rights, and equality, producing a shift from issue-based coordination to what this article terms “strategic coexistence”, a hybrid alliance formed across previously distant ideological and organisational positions. Diagnostic framing identifies anti-gender reforms as an existential threat, prognostic framing centres on alliance-building, movement memory, and inclusive organisational practices and motivational framing foregrounds shared destiny, solidarity, and the symbolic significance of LGBTQI+ rights. The analysis reveals that while this recontextualisation widens the basis for coalition, the resulting alliance remains structurally unbalanced and fragile. Hierarchical power relations, uneven exposure to political risk, and selective silence, particularly regarding LGBTQI+ concerns, limit the depth and durability of alliances. In this context, LGBTQI+ rights serve both as a catalyst for broad-based mobilisation and as a litmus test for democratic commitment, disclosing the limitations of transversal solidarity under authoritarian regimes. © 2026 Elsevier Ltd.Article Regular AdS3 Black Holes From a Regularized Gauss-Bonnet Coupling(Elsevier, 2026) Alkac, Gokhan; Mesta, Murat; Unal, GonulWe obtain a three-dimensional bi-vector-tensor theory of the generalized Proca class by regularizing the Gauss-Bonnet invariant within the Weyl geometry. We show that the theory admits a regular AdS3 black hole solution with primary hairs. Introducing a deformation in the theory, a different regular AdS3 black hole solution is obtained. Charged generalizations of these solutions are given by coupling to Born-Infeld electrodynamics.Article Linear Two-Dimensional Consecutive K-Type Systems in Multi-State Case(Elsevier Ltd, 2026) Yi, H.; Balakrishnan, N.; Li, X.In the context of consecutive k -type systems, multi-state system models are only considered in the one-dimensional case and not in the two-dimensional case due to the complexity involved. In this paper, we consider several linear two-dimensional consecutive k -type systems in the multi-state case for the first time, as generalization of consecutive k -out-of- n systems and l -consecutive- k -out-of- n systems without/with overlapping. These systems include multi-state linear connected-(k , r)-out-of-(m, n): G systems, multi-state linear connected-(k , r)-or-(r , k)-out-of-(m, n): G systems, multi-state linear l -connected-(k , r)-out-of-(m, n): G systems without/with overlapping, and multi-state linear l -connected-(k , r)-or-(r , k)-out-of-(m, n): G systems without/with overlapping. We then derive their reliability functions by using the finite Markov chain imbedding approach (FMCIA) in a new way. We also present several examples to illustrate all the results developed here. © 2026 Elsevier Ltd.Article A Computationally Efficient Approximation for Fractional Differencing: First-Order Operators(Pergamon-Elsevier Science Ltd, 2026) Omay, Tolga; Baleanu, DumitruThis paper introduces the First-Order Fractional Differencing (FOFD) operator that substantially reduces the computational burden of fractional differencing for large-scale applications. While the standard Gr & uuml;nwald-Letnikov (GL) operator requires O(T2) operations for a series of length T, and recent FFT-based methods achieve O(T log T), our FOFD operator requires only O(T) operations through a simple two-point recursion. We develop an optimal weight calibration framework that ensures this computational efficiency does not compromise statistical accuracy, deriving a general formula wopt = d & sdot; (1-0.9 rho)beta(p) that adapts to the persistence structure of autoregressive processes. Empirical applications demonstrate substantial improvements: for the Chicago Fed National Financial Conditions Index with extreme persistence (rho= 0.992), optimal weight calibration reduces approximation error by 93% while preserving the autocorrelation structure of the GL operator. For a series of 10,000 observations, our method requires 20,000 operations compared to 530,000 for FFT-based methods and 50 million for standard implementations-enabling fractional differencing in real-time and high-frequency contexts previously infeasible due to computational constraints. The method's simplicity, requiring no specialized libraries and providing direct implementation through our calibration formula, makes it immediately accessible to practitioners while maintaining the long-memory properties essential for financial time series modeling.Article Fröbenius Expansions for Second-Order Random Differential Equations: Stochastic Analysis and Applications to Lindley-Type Damping Models(Elsevier B.V., 2026) Halim, H.; Kerker, M.A.; Boduroğlu, E.This paper develops a Frobenius series framework for the stochastic analysis of second–order random differential equations of the form Y¨(t)+A(t)Y˙(t)=0,where the damping coefficient A(t) is a positive stochastic process and the initial conditions are square–integrable random variables. Assuming mean–square analyticity of A(t) in a neighborhood of the initial time, we establish existence and uniqueness of the solution in L2(Ω) and derive exponentially convergent truncation error bounds for the associated Frobenius expansion. The resulting series representation enables the numerical approximation of the probability density function of Y(t) via Monte Carlo simulation. To improve computational efficiency, a control variates strategy is incorporated for variance reduction. A comprehensive numerical study is conducted for a broad family of positive, right–skewed damping distributions, including the Lindley, XLindley, New XLindley (NXLD), Gamma–Lindley, Inverse–Lindley, Truncated–Lindley, Log–Lindley, and a newly proposed Mixed Lindley–Uniform model. The simulations illustrate how different tail behaviors and boundedness properties of the damping coefficient influence the stochastic dynamics and the accuracy of density estimation. Finally, stylized applications to option pricing and Value–at–Risk estimation are presented to illustrate how the Frobenius–based framework and control variates methodology can be embedded within standard uncertainty quantification workflows. Overall, the proposed approach provides a flexible and computationally efficient tool for the analysis of randomly damped dynamical systems. © 2026 Elsevier B.V.Book Part Citation - Scopus: 16ISRM Suggested Methods for Determining the Creep Characteristics of Rock(Springer International Publishing, 2014) Aydan, Ö.; Ito, T.; Özbay, U.; Kwasniewski, M.; Shariar, K.; Okuno, T.; Okada, T.
