Entropy最新文献_第5页

The Structure of Bit-String Similarity Networks.

IF 2.1 3区物理与天体物理

Entropy Pub Date : 2025-01-10 DOI: 10.3390/e27010057

David M Schneider, Damián H Zanette

引用次数: 0

Advanced Monte Carlo for Acquisition Sampling in Bayesian Optimization.

IF 2.1 3区物理与天体物理

Entropy Pub Date : 2025-01-10 DOI: 10.3390/e27010058

Javier Garcia-Barcos, Ruben Martinez-Cantin

{"title":"Advanced Monte Carlo for Acquisition Sampling in Bayesian Optimization.","authors":"Javier Garcia-Barcos, Ruben Martinez-Cantin","doi":"10.3390/e27010058","DOIUrl":"10.3390/e27010058","url":null,"abstract":"Optimizing complex systems usually involves costly and time-consuming experiments, where selecting the experiments to perform is fundamental. Bayesian optimization (BO) has proved to be a suitable optimization method in these situations thanks to its sample efficiency and principled way of learning from previous data, but it typically requires that experiments are sequentially performed. Fully distributed BO addresses the need for efficient parallel and asynchronous active search, especially where traditional centralized BO faces limitations concerning privacy in federated learning and resource utilization in high-performance computing settings. Boltzmann sampling is an embarrassingly parallel method that enables fully distributed BO using Monte Carlo sampling. However, it also requires sampling from a continuous acquisition function, which can be challenging even for advanced Monte Carlo methods due to its highly multimodal nature, constrained search space, and possibly numerically unstable values. We introduce a simplified version of Boltzmann sampling, and we analyze multiple Markov chain Monte Carlo (MCMC) methods with a numerically improved log EI implementation for acquisition sampling. Our experiments suggest that by introducing gradient information during MCMC sampling, methods such as the MALA or CyclicalSGLD improve acquisition sampling efficiency. Interestingly, a mixture of proposals for the Metropolis-Hastings approach proves to be effective despite its simplicity.","PeriodicalId":11694,"journal":{"name":"Entropy","volume":"27 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11764573/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143032635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Subdiffusion Equation with Fractional Caputo Time Derivative with Respect to Another Function in Modeling Superdiffusion.

IF 2.1 3区物理与天体物理

Entropy Pub Date : 2025-01-09 DOI: 10.3390/e27010048

Tadeusz Kosztołowicz

{"title":"Subdiffusion Equation with Fractional Caputo Time Derivative with Respect to Another Function in Modeling Superdiffusion.","authors":"Tadeusz Kosztołowicz","doi":"10.3390/e27010048","DOIUrl":"10.3390/e27010048","url":null,"abstract":"Superdiffusion is usually defined as a random walk process of a molecule, in which the time evolution of the mean-squared displacement, σ2, of the molecule is a power function of time, σ2(t)∼t2/γ, with γ∈(1,2). An equation with a Riesz-type fractional derivative of the order γ with respect to a spatial variable (a fractional superdiffusion equation) is often used to describe superdiffusion. However, this equation leads to the formula σ2(t)=κt2/γ with κ=∞, which, in practice, makes it impossible to define the parameter γ. Moreover, due to the nonlocal nature of this derivative, it is generally not possible to impose boundary conditions at a thin partially permeable membrane. We show a model of superdiffusion based on an equation in which there is a fractional Caputo time derivative with respect to another function, g; the spatial derivative is of the second order. By choosing the function in an appropriate way, we obtain the g-superdiffusion equation, in which Green's function (GF) in the long time limit approaches GF for the fractional superdiffusion equation. GF for the g-superdiffusion equation generates σ2 with finite κ. In addition, the boundary conditions at a thin membrane can be given in a similar way as for normal diffusion or subdiffusion. As an example, the filtration process generated by a partially permeable membrane in a superdiffusive medium is considered.","PeriodicalId":11694,"journal":{"name":"Entropy","volume":"27 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11764444/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143032922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Entropy-Based Stochastic Optimization of Multi-Energy Systems in Gas-to-Methanol Processes Subject to Modeling Uncertainties.

IF 2.1 3区物理与天体物理

Entropy Pub Date : 2025-01-09 DOI: 10.3390/e27010052

Xueteng Wang, Jiandong Wang, Mengyao Wei, Yang Yue

{"title":"Entropy-Based Stochastic Optimization of Multi-Energy Systems in Gas-to-Methanol Processes Subject to Modeling Uncertainties.","authors":"Xueteng Wang, Jiandong Wang, Mengyao Wei, Yang Yue","doi":"10.3390/e27010052","DOIUrl":"10.3390/e27010052","url":null,"abstract":"In gas-to-methanol processes, optimizing multi-energy systems is a critical challenge toward efficient energy allocation. This paper proposes an entropy-based stochastic optimization method for a multi-energy system in a gas-to-methanol process, aiming to achieve optimal allocation of gas, steam, and electricity to ensure executability under modeling uncertainties. First, mechanistic models are developed for major chemical equipments, including the desulfurization, steam boilers, air separation, and syngas compressors. Structural errors in these models under varying operating conditions result in noticeable model uncertainties. Second, Bayesian estimation theory and the Markov Chain Monte Carlo approach are employed to analyze the differences between historical data and model predictions under varying operating conditions, thereby quantifying modeling uncertainties. Finally, subject to constraints in the model uncertainties, equipment capacities, and energy balance, a multi-objective stochastic optimization model is formulated to minimize gas loss, steam loss, and operating costs. The entropy weight approach is then applied to filter the Pareto front solution set, selecting a final optimal solution with minimal subjectivity and preferences. Case studies using Aspen Hysys-based simulations show that optimization solutions considering model uncertainties outperform the counterparts from a standard deterministic optimization in terms of executability.","PeriodicalId":11694,"journal":{"name":"Entropy","volume":"27 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11765456/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143032713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Generalized Adaptive Diversity Gradient Descent Bit-Flipping with a Finite State Machine.

IF 2.1 3区物理与天体物理

Entropy Pub Date : 2025-01-09 DOI: 10.3390/e27010049

Jovan Milojković, Srdjan Brkić, Predrag Ivaniš, Bane Vasić

引用次数: 0

Measuring Complexity in Manufacturing: Integrating Entropic Methods, Programming and Simulation.

IF 2.1 3区物理与天体物理

Entropy Pub Date : 2025-01-09 DOI: 10.3390/e27010050

Germán Herrera-Vidal, Jairo R Coronado-Hernández, Ivan Derpich-Contreras, Breezy P Martínez Paredes, Gustavo Gatica

{"title":"Measuring Complexity in Manufacturing: Integrating Entropic Methods, Programming and Simulation.","authors":"Germán Herrera-Vidal, Jairo R Coronado-Hernández, Ivan Derpich-Contreras, Breezy P Martínez Paredes, Gustavo Gatica","doi":"10.3390/e27010050","DOIUrl":"10.3390/e27010050","url":null,"abstract":"This research addresses complexity in manufacturing systems from an entropic perspective for production improvement. The main objective is to develop and validate a methodology that develops an entropic metric of complexity in an integral way in production environments, through simulation and programming techniques. The methodological proposal is composed of six stages: (i) Case study, (ii) Hypothesis formulation, (iii) Discrete event simulation, (iv) Measurement of entropic complexity by applying Shannon's information theory, (v) Entropy analysis, and (vi) Statistical analysis by ANOVA. The results confirm that factors such as production sequence and product volume significantly influence the structural complexity of the workstations, with station A being less complex (0.4154 to 0.9913 bits) compared to stations B and C, which reached up to 2.2084 bits. This analysis has shown that optimizing production scheduling can reduce bottlenecks and improve system efficiency. Furthermore, the developed methodology, validated in a case study of the metalworking sector, provides a quantitative framework that combines discrete event simulation and robust statistical analysis, offering an effective tool to anticipate and manage complexity in production. In synthesis, this research presents an innovative methodology to measure static and dynamic complexity in manufacturing systems, with practical application to improve efficiency and competitiveness in the industrial sector.","PeriodicalId":11694,"journal":{"name":"Entropy","volume":"27 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11765125/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143032789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Is Word Order Responsive to Morphology? Disentangling Cause and Effect in Morphosyntactic Change in Five Western European Languages.

IF 2.1 3区物理与天体物理

Entropy Pub Date : 2025-01-09 DOI: 10.3390/e27010053

Julie Nijs, Freek Van de Velde, Hubert Cuyckens

{"title":"Is Word Order Responsive to Morphology? Disentangling Cause and Effect in Morphosyntactic Change in Five Western European Languages.","authors":"Julie Nijs, Freek Van de Velde, Hubert Cuyckens","doi":"10.3390/e27010053","DOIUrl":"10.3390/e27010053","url":null,"abstract":"This study examines the relationship between morphological complexity and word order rigidity, addressing a gap in the literature regarding causality in linguistic changes. While prior research suggests that the loss of inflectional morphology correlates with the adoption of fixed word order, this study shifts the focus from correlation to causation. By employing Kolmogorov complexity as a measure of linguistic complexity alongside Granger Causality to examine causal relationships, we analyzed data from Germanic and Romance languages over time. Our findings indicate that changes in morphological complexity are statistically more likely to cause shifts in word order rigidity than vice versa. The causal asymmetry is robustly borne out in Dutch and German, though waveringly in English, as well as in French and Italian. Nowhere, however, is the asymmetry reversed. Together, these results can be interpreted as supporting the idea that a decline in morphological complexity causally precedes a rise in syntactic complexity, though further investigation into the underlying factors contributing to the differing trends across languages is needed.","PeriodicalId":11694,"journal":{"name":"Entropy","volume":"27 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11765092/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143032753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Self-Assembly of Particles on a Curved Mesh.

IF 2.1 3区物理与天体物理

Entropy Pub Date : 2025-01-09 DOI: 10.3390/e27010046

Gabriele Costa, Santi Prestipino

引用次数: 0

Thompson Sampling for Non-Stationary Bandit Problems.

IF 2.1 3区物理与天体物理

Entropy Pub Date : 2025-01-09 DOI: 10.3390/e27010051

Han Qi, Fei Guo, Li Zhu

引用次数: 0

Quantum Contextual Hypergraphs, Operators, Inequalities, and Applications in Higher Dimensions.