Within the context of a granular binary mixture, the Boltzmann equation for d-dimensional inelastic Maxwell models is used to determine the collisional moments of the second, third, and fourth degrees. The velocity moments of the distribution function for each substance are used to exactly quantify collisional events when mass transport (diffusion) is absent, meaning the mass flux for each substance is zero. Coefficients of normal restitution, along with mixture parameters (mass, diameter, and composition), determine the associated eigenvalues and cross coefficients. These results are applied to the analysis of the time evolution of moments, scaled by a thermal speed, in two non-equilibrium states: the homogeneous cooling state (HCS) and the uniform shear flow (USF) state. Given particular parameter values, the temporal moments of the third and fourth degree in the HCS differ from those of simple granular gases, potentially diverging. A thorough examination of how the parameter space of the mixture affects the time-dependent behavior of these moments is conducted. Selleckchem SHIN1 Subsequently, the temporal evolution of the second- and third-degree velocity moments within the USF is investigated within the tracer regime (specifically, when one species' concentration is negligible). Unsurprisingly, the second-degree moments, while always convergent, exhibit the possibility of divergent third-degree moments for the tracer species in the long run.
This study addresses the optimal containment control of multi-agent systems exhibiting nonlinearity and partial dynamic uncertainty using an integral reinforcement learning method. Integral reinforcement learning alleviates the need for stringent drift dynamics specifications. The control algorithm's convergence is assured by the proven equivalence of the integral reinforcement learning method and the model-based policy iteration approach. To solve the Hamilton-Jacobi-Bellman equation for every follower, a single critic neural network, characterized by a modified updating law, guarantees the asymptotic stability of the weight error dynamic. From the analysis of input-output data, each follower's approximate optimal containment control protocol is derived using a critic neural network. The proposed optimal containment control scheme guarantees the stability of the closed-loop containment error system, without fail. Empirical simulation data validates the effectiveness of the introduced control architecture.
Deep neural networks (DNNs) underpinning natural language processing (NLP) models are vulnerable to backdoor attacks. The effectiveness of current backdoor defenses is hampered by restricted coverage and limited situational awareness. We advocate a textual backdoor defense strategy, employing deep feature categorization. To carry out the method, deep feature extraction and classifier design are essential steps. The method capitalizes on the discernible differences between deep features extracted from poisoned and benign data samples. Both online and offline situations benefit from the inclusion of backdoor defense. Defense experiments were performed on two models and two datasets, employing a range of backdoor attacks. The experimental results unequivocally indicate this defense approach is more effective than the baseline defense method.
To bolster the predictive strength of financial time series models, the practice of incorporating sentiment analysis data into the feature space is commonly implemented. Besides, deep learning frameworks and advanced strategies are becoming more commonplace due to their efficiency. This work examines the state-of-the-art in financial time series forecasting, using sentiment analysis as a critical component of the comparison. Rigorous testing was applied to 67 distinct feature configurations incorporating stock closing prices and sentiment scores, spanning a variety of datasets and metrics, using an extensive experimental process. Across two case studies, encompassing a comparison of methods and a comparison of input feature configurations, a total of 30 cutting-edge algorithmic approaches were employed. The results, when aggregated, suggest, first, the wide application of the recommended method, and, second, a conditional improvement in model efficiency after incorporating sentiment setups into specific forecasting windows.
Quantum mechanics' probabilistic representation is summarized concisely, followed by examples of probability distributions for quantum oscillators at temperature T and the dynamic behavior of quantum states for a charged particle in an electrical capacitor's electric field. Varying probability distributions, describing the dynamic states of the charged particle, are procured via the utilization of explicit time-dependent integral expressions of motion, which are linear in both position and momentum. An analysis of the entropies linked to the probability distributions of starting coherent states for charged particles is undertaken. Through the Feynman path integral, the probabilistic nature of quantum mechanics is elucidated.
Vehicular ad hoc networks (VANETs) have recently attracted significant interest owing to their substantial promise in improving road safety, managing traffic flow, and providing infotainment services. IEEE 802.11p, a standard for vehicular ad hoc networks (VANETs), has been under consideration for more than ten years, focusing on the medium access control (MAC) and physical (PHY) layers. Existing analytical procedures for performance assessment of the IEEE 802.11p MAC, while studied, demand significant improvement. In this paper, a 2-dimensional (2-D) Markov model is proposed to evaluate the saturated throughput and average packet delay of IEEE 802.11p MAC in VANETs, incorporating the capture effect within a Nakagami-m fading channel. Importantly, the mathematical representations for successful transmission, collisions during transmission, saturated throughput, and the average packet delay are carefully deduced. A demonstration of simulation results validates the accuracy of the proposed analytical model, which outperforms existing models in predicting saturated throughput and average packet delay.
To create the probability representation of quantum system states, the quantizer-dequantizer formalism is employed. Classical system states and their probabilistic counterparts are scrutinized, highlighting the comparisons between the two. Examples of probability distributions demonstrate the parametric and inverted oscillator system.
We aim in this paper to provide a preliminary investigation into the thermodynamics of particles that comply with monotone statistics. We present a revised approach, block-monotone, for achieving realistic physical outcomes, based on a partial order arising from the natural ordering in the spectrum of a positive Hamiltonian possessing a compact resolvent. The block-monotone scheme is not comparable to the weak monotone scheme; it becomes identical to the usual monotone scheme when every eigenvalue of the Hamiltonian is non-degenerate. A deep dive into a model based on the quantum harmonic oscillator reveals that (a) the grand partition function's calculation doesn't use the Gibbs correction factor n! (associated with indistinguishable particles) in its series expansion based on activity; and (b) the elimination of terms from the grand partition function produces a kind of exclusion principle, analogous to the Pauli exclusion principle affecting Fermi particles, that stands out at high densities but fades at low densities, consistent with expectations.
Adversarial attacks on image classification are critical to AI security. Image-classification adversarial attack methods commonly employed in white-box settings, relying on the availability of the target model's gradients and network structures, are often impractical and less applicable in the context of real-world image processing However, adversarial attacks operating within a black-box framework, immune to the limitations stipulated above and coupled with reinforcement learning (RL), appear to provide a viable avenue for researching an optimized evasion policy. Existing reinforcement learning-based attack strategies unfortunately underperform in terms of achieving success. Selleckchem SHIN1 Given the obstacles, we propose an adversarial attack method (ELAA) using ensemble learning, aggregating and optimizing multiple reinforcement learning (RL) base learners, which ultimately highlights the vulnerabilities in image classification models. Experimental data reveal a 35% greater attack success rate for the ensemble model compared to its single-model counterpart. Compared to baseline methods, the attack success rate of ELAA is 15% higher.
Fractal characteristics and dynamical complexities of Bitcoin/US dollar (BTC/USD) and Euro/US dollar (EUR/USD) returns are explored in this article, concentrating on the period surrounding the COVID-19 pandemic. In particular, the asymmetric multifractal detrended fluctuation analysis (A-MF-DFA) method was utilized to explore the temporal progression of the asymmetric multifractal spectrum's parameters. We investigated the temporal characteristics of Fuzzy entropy, non-extensive Tsallis entropy, Shannon entropy, and Fisher information. We undertook research to gain a deeper understanding of how the pandemic affected two crucial currencies, impacting the modern financial system in novel ways. Selleckchem SHIN1 In both pre- and post-pandemic periods, BTC/USD returns displayed a consistent pattern, whereas EUR/USD returns demonstrated an anti-persistent pattern, according to our results. After the COVID-19 outbreak, a greater degree of multifractality, more pronounced large fluctuations in prices, and a marked decrease in the complexity (i.e., a gain in order and information content and a loss of randomness) were observed for the return patterns in both BTC/USD and EUR/USD. The sudden surge in the intricacy of the overall situation appears to have been directly influenced by the World Health Organization's (WHO) declaration that COVID-19 was a global pandemic.