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Simultaneous Probe of the Charm and Bottom Quark Yukawa Couplings Using (Formula presented) Events
No full textA search for the standard model Higgs boson decaying to a charm quark-antiquark pair, (Formula presented), produced in association with a top quark-antiquark pair ((Formula presented)) is presented. The search is performed with data from proton-proton collisions at (Formula presented), corresponding to an integrated luminosity of (Formula presented). Advanced machine learning techniques are employed for jet flavor identification and event classification. The Higgs boson decay to a bottom quark-antiquark pair is measured simultaneously and the observed (Formula presented) event rate relative to the standard model expectation is (Formula presented). The observed (expected) upper limit on the product of production cross section and branching fraction (Formula presented) is 0.11 (0.13) pb at 95% confidence level, corresponding to 7.8 (8.7) times the standard model prediction. When combined with the previous search for (Formula presented) via associated production with a (Formula presented) or (Formula presented) boson, the observed (expected) 95% confidence interval on the Higgs-charm Yukawa coupling modifier, (Formula presented), is (Formula presented) (2.7), the most stringent constraint to date
TAMING of the abrupt emergence
No full textThis paper offers a scientifically informed reconstruction of the continuity argument in support of a modest version of a loosely panpsychist tenet: the continuity of mind. This approach does so by engaging with two closely connected recent proposals: the problem of the abruptness of the emergence of consciousness in the context of Dennett’s account of the emergence of comprehension from competence and Levin’s “technological approach to minds everywhere” (TAME), which illustrates how to reconstruct the continuity argument and to address the issue of abrupt emergence. The stance put forth advocates a view that holds its ground within an evolutionary narrative of consciousness. In conclusion, our proposal (i) aligns with the notion of smooth gradualism in the process of consciousness genesis and (ii) recognises the presence of diverse instances of collective intelligence throughout the evolutionary trajectory. Thus, the proposal remains valid irrespective of whether evolutionary progression occurred through natural selection or through alternative methods, such as designed or artefactual means, as in TAME
AC Loss Reduction in HTS Stator Windings of an Air-cored Axial-flux Wind Turbine Generator via Optimized End-winding Designs
No full textHigh AC loss in stator windings is one of the key challenges in realizing fully high-temperature superconducting (HTS) wind turbine generators, which offer significant advantages in compactness and weight compared to conventional machines. Among the sources of AC loss, the perpendicular magnetic field component (relative to the HTS tape surface) is particularly dominant, while the parallel field contributes much less. Therefore, minimizing the perpendicular field in the stator windings is essential when designing a fully HTS generator. In this work, we present a 5 MW-class, air-cored, axial-flux fully HTS wind turbine generator modeled using the finite element method (FEM). The T-A formulation and interpolated Jc(B) characteristics are used to simulate the electromagnetic behavior of the HTS windings. A moving mesh approach is employed to simulate the rotor movement. Simulation results show that the outer-stage stator windings experience significantly higher AC loss than the inner-stage windings, despite delivering the same power output. By optimizing the rotor end-winding geometry, the perpendicular magnetic field in the outer-stage windings was significantly reduced, resulting in a 77% decrease in total AC loss across the HTS stator windings
Key-Updatable Identity-Based Signature Schemes
No full textIdentity-based signature (IBS) schemes eliminate the need for certificate management, thereby reducing communication and computational overhead. A major challenge, however, is the efficient update or revocation of compromised keys, as existing approaches such as revocation lists or periodic key renewal incur significant network costs in dynamic settings. We address this challenge by introducing a symmetric element that enables key updates in IBS schemes through a single multicast message. Our approach achieves logarithmic network overhead in the number of keys, with constant computation and memory costs. We further propose a general framework that transforms any IBS scheme into a key-updatable IBS scheme (KUSS), and formalize the associated security requirements, including token security, forward security, and post-compromise security. The versatility of our framework is demonstrated through five instantiations based on Schnorr-type, pairing-based, and isogeny-based IBS, and we provide a detailed security analysis
Type-2 fuzzy logic empowered trajectory prediction for wireless sensor networks
No full textWireless sensor networks (WSNs) are increasingly utilized for object trajectory identification and tracking, especially in scenarios where global positioning system (GPS) or radio frequency identification (RFID) technologies are unavailable. Trajectory extraction in such networks presents significant challenges due to the need to analyze spatio-temporal sensor data and address uncertainty in trajectory points. To overcome these challenges, we propose a multilevel object-tracking algorithm powered by Interval Type-2 (IT2) Fuzzy Logic System (FLS), an Artificial Intelligence (AI) approach designed to represent and manage uncertainty effectively. Our methodology leverages the capabilities of IT2-FLS to accurately generate and predict object trajectories, even in the presence of noisy or incomplete data, by emulating human reasoning and decision-making processes. Comparative analyses confirm that our IT2-FLS-based approach outperforms the T1-FLS alternative by requiring fewer rules, achieving superior results in trajectory reconstruction and prediction tasks. Furthermore, the evaluations demonstrate the robustness of the proposed system in anomaly detection and predictive analytics, outperforming leading classification algorithms. The method not only delivers high accuracy but also preserves model interpretability and reduces rule complexity, which are critical for efficient operation in WSNs. These findings establish the IT2-FLS-based methodology as an innovative and effective AI-driven solution for trajectory prediction in WSNs, combining enhanced accuracy, robustness, and practical applicability in complex and uncertain environments
Test Platform for Three-Dimensional Printing Modeling Using Quadcopter-Mounted Gimbal
No full textThis paper introduces a specialized testing platform expressly crafted for assessing the efficacy of gimbals when integrated into quadcopters for applications within the realm of three-dimensional (3D) printing. The surge in the adoption of quadcopter-mounted gimbals in 3D-printing can be attributed to their remarkable capacity to overcome size limitations and positional constraints prevalent in the manufacturing landscape. The investigation carried out here comprehensively examines the gimbal’s performance, encompassing a spectrum of control tests and evaluations. At its core, the gimbal system plays a pivotal role in increasing stability while simultaneously mitigating the harmful effects of vibrations in the context of 3D-printing applications. Furthermore, it explores alternative strategies for achieving precision and control in the intricate movements intrinsic to 3D-printing. In summation, the overarching objective of this study is to shed light on the profound impact that gimbal systems wield over large-area 3D-printing processes. The insights gleaned from this research are poised to contribute to the collective understanding of how gimbals can be harnessed to optimize and refine the 3D-printing workflow. In essence, this paper is a pioneering endeavor that lays the foundation for future advancements in the symbiotic relationship between gimbals and quadcopters in the dynamic domain of large area 3D-printing
Understanding the Link Between Epistemological Beliefs and Academic Achievement: A Meta-Analytic Review
No full textEnhancing human tsunami vulnerability analysis with open-source data and data-driven methodologies
No full textThis study reassesses the human vulnerability to tsunamis by reducing dependency on high-resolution data and expert-driven evaluations. The original MeTHuVA (METU Metropolitan Tsunami Human Vulnerability Assessment) method, designed for metropolitan areas, is adapted to leverage open-source datasets and data-driven methodologies. The approach investigates three successive steps to reduce data and expert dependency in the Evacuation Resilience component of MeTHuVA method, (i) utilizing open-source data, (ii) applying value functions for parameter value transformation, and (iii) employing objective weighting methods to determine parameter importance. The calculations for the proposed methods are made for Bakirkoy district of Istanbul, where MeTHuVA method was previously successfully applied. The overall correlation between Evacuation Resilience maps derived from open-source and authoritative high-resolution datasets reached 0.71, supporting that the analyses performed using open-source data can provide a reasonably comparable alternative for vulnerability assessment in the selected study area. Additionally, value functions and objective weighting methods (Entropy, CRITIC, MEREC) effectively replicated expert-based processes, with resulted Evacuation Resilience maps achieving correlation coefficients above 0.9, indicating that data-driven methods can have a potential of providing scalable, adaptable, and reliable alternatives to expert-driven assessments. As coastal vulnerability increases due to rising sea levels, the growing availability and improving quality of open-source datasets and exploration of methods with lesser user interference offer promising pathways for more accessible and automated tsunami vulnerability and risk assessments that are suitable for diverse global contexts
Variational approach to the snake instability of a Bose-Einstein condensate soliton
No full textSolitons are striking manifestations of nonlinearity, encountered in diverse physical systems such as water waves, nonlinear optics, and Bose-Einstein condensates (BECs). In BECs, dark solitons emerge as exact stationary solutions of the one-dimensional Gross-Pitaevskii equation. While they can be long lived in elongated traps, their stability is compromised in higher dimensions due to the snake instability, which leads to the decay of the soliton into vortex structures among other excitations. We investigate the dynamics of a dark soliton in a Bose-Einstein condensate confined in an anisotropic harmonic trap. Using a variational ansatz that incorporates both the transverse bending of the soliton plane and the emergence of vortices along the nodal line, we derive equations of motion governing the soliton's evolution. This approach allows us to identify stable soliton-vortex oscillation modes as well as the growth rates of the unstable perturbations. In particular, we determine the critical trap anisotropy required to suppress the snake instability. Our analytical predictions are in good agreement with full numerical simulations of the Gross-Pitaevskii equation