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Semi-Markov Approach to Reliability Evaluation in Two-Unit Standby Repairable System with Priority in Use

Modern systems incorporate an increasing number of components performing complex functions, necessitating the development of adequate mathematical models for their reliability. Particular attention should be paid to mission-critical units, whose failure may lead to the breakdown...

On classical and Gorenstein homological invariants of rings

We prove that, over any ring R, the supremum of the projective dimensions of the flat left R-modules coincides with the supremum of the Gorenstein projective dimensions of the Gorenstein flat left R-modules. As a consequence, we obtain new characterizations of left n-perfect ring...

How can critical actors be incentivised to take a systems approach to pursue preventative public health?

Introduction In this article we explore how critical actors can be incentivised to take a systems approach to pursue preventative public health. More specifically, we focus on the link between urban environments and their effect on non-communicable diseases (NCDs), such as obesit...

Generalized Mazur Patterns and Immersed Heegaard Floer Homology

Generalizing prior work of Levine, we give infinitely many examples of pattern knots P such that P(K) is not slice in any rational homology 4-ball, for any companion knot K. To show this, we establish a closed formula for the concordance invariants τ and ε of a family of satellit...

Quasi sdf-absorbing ideals in commutative rings

This paper introduces and studies quasi sdf-absorbing ideals as a generalization of sdf-absorbing ideals. We investigate the stability of this property under various constructions, including localization, surjective images, Nagata idealizations, and amalgamations. We establish co...

More on Lanzhou and Ad-hoc Lanzhou indices of Graphs

Topological indices are graph-theoretical descriptors that offer a computationally efficient means of predicting the physicochemical properties of chemical compounds, thereby reducing the need for extensive, resource-intensive laboratory experimentation. The Lanzhou index of a si...

Bandwidth-Enhanced Low-Frequency Piezoelectric Energy Harvesting via Multimodal Response of a Planar Fermat Spiral Harvester

Enhancing the bandwidth of low-frequency vibration energy harvesting remains challenging for conventional piezoelectric cantilever harvesters because their effective response is usually confined to a narrow resonance band. This study proposes a compact Fermat spiral piezoelectric...

Obstacle-Aware Game-Theoretic Model Predictive Control for Quadrotor Pursuit-Evasion

Effective autonomous pursuit of an intelligent adversary in complex environments requires more than reactive tracking or passive target extrapolation. This study introduces OA-GT-MPC, an obstacle-aware game-theoretic model predictive control framework for quadrotor pursuit under...

Spectral properties of commutators on harmonic Bergman spaces of the unit disk

In this paper, we determine the asymptotic behavior of the singular values of the commutator [Formula: see text] acting on [Formula: see text], where [Formula: see text] is the operator of multiplication by a subharmonic function [Formula: see text] on [Formula: see text] and har...

Threshold dynamics of multiscale stochastic HIV model with Ornstein–Uhlenbeck process

HIV transmission involves a bidirectional coupling between microscale viral dynamics and macroscale disease prevalence: higher viral loads increase infectiousness and mortality, while prevalence feeds back to shape within-host viral evolution. This coupled process is inevitably i...

Deep Reinforcement Learning with State Uncertainty Estimation for Continuous Control of Dynamic Complex Systems

Deep reinforcement learning has achieved remarkable success in continuous control tasks. Modeling and decision-making for dynamic complex systems remain particularly challenging due to nonlinear dynamics, stochastic disturbances, and uncertain observations, making uncertainty-awa...

A mathematical model of HPAI transmission between dairy cattle and wild birds with environmental effects

Highly pathogenic avian influenza (HPAI), particularly H5N1, poses an increasing threat at the wildlife–livestock–environment interface, with recent detections in dairy cattle motivating mechanistic models that capture multi-host transmission and environmental persistence. We dev...

Strong Differential Subordination and Superordination Results of λ-Pseudo-Convex Functions with Respect to Symmetrical Points Associated with Hadamard Product

In this study, by selecting appropriate families of admissible functions, we derive strong differential subordination and superordination results for λ-pseudo-convex functions with respect to symmetric points in the open unit disk U. Furthermore, these findings are utilized to es...

Flying a Quadrotor with Unknown Actuators and Sensor Configuration

Though control algorithms for multirotor Unmanned Air Vehicle (UAV) are well understood, the configuration, parameter estimation, and tuning of flight control algorithms take quite some time and resources. In previous work, we have shown that it is possible to identify the contro...

The sufficiently trapped surface

Roger Penrose introduced the concept of the trapped surface: a spacelike hypersurface where the two null normals have negative expansion. The trapped surface along with the null convergence condition leads to null geodesic incompleteness. If an event horizon forms, the trapped su...

Tipping Points in Coral Reef Ecosystems: Interplay of Carbon Cycle Disruption and Ocean Warming

Coral reefs are among the most vital ecosystems on the planet, sustaining exceptionally high biodiversity and providing essential ecological services to coastal communities. However, coral populations have been steadily declining for decades, primarily due to stressors such as ri...

Baryon number density dependent charged compact star admixed with dark energy: consistent with recent observational results

In this work, we investigate an anisotropic charged compact star model interpreted as a strange quark star in [Formula: see text]-equilibrium admixed with dark energy. The effects of finite strange quark mass ([Formula: see text]) and baryon number density ([Formula: see text]) a...

Joint Optimization of Delay and Energy Efficiency for UAV Task Offloading and Cooperative Scheduling

The growing demand for multimedia services in Internet of Things (IoT) networks has significantly increased the traffic load on backhaul links, making Mobile Edge Caching (MEC) a key technology for reducing content delivery latency. Unmanned Aerial Vehicles (UAVs) can serve as mo...

Emulation and Mitigation of Multiple bit errors in SRAM based Space FPGAs

Static random-access memory (SRAMs) systems are currently experiencing more failures as a result of the aggressive CMOS integration density. Burst faults in data are caused by different noises that affect data transmission in modern space communications. Therefore, the error corr...

Optical soliton perturbation, phase portrait and sensitivity analysis in birefringent fibers with the stochastic complex Ginzburg-Landau equation having cubic-quintic-septic-nonic nonlinearities

Optical soliton solutions, chaotic behaviors and bifurcation analysis of the perturbed complex Ginzburg-Landau equation having non-Kerr law media with the effect of multiplicative white noise in birefringent fibers are researched, for the first time, in this study. Perturbation t...