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GEOENERGY SCIENCE AND ENGINEERING 2025年 250卷

作者： Zhang, Haoyu Wu, Wensheng Chen, Zhangxin Song, Xiaoyu Taiyuan Univ Technol Coll Min Engn Taiyuan 030024 Peoples R China China Univ Petr State Key Lab Petr Resources & Prospecting Beijing 102249 Peoples R China Eastern Inst Technol Ningbo 315100 Peoples R China Univ Calgary Dept Chem & Petr Engn Calgary AB T2N 1N4 Canada

In complex well conditions, the evaluation of cased-hole logging parameters such as formation density rho b, casing thickness hs, cement sheath thickness hcand cement sheath density rho c can effectively reduce the risk of downhole operations when compared to open-hole logging. Moreover, the use of X-ray sources to replace isotopic radioactive sources in nuclear logging has emerged as a new trend, but there is relatively little research on the calculation of logging parameters for X-ray cased-hole logging. As a result, further research on forward modeling of detector response and data inversion is required. Because the cement sheath density response was not included in the prior forward modeling formula, we intend to include a geological model constraint whose objective is precisely the cement sheath density in the case of unclear cement sheath circumstances. To achieve this, the energy window related to the cement sheath density was identified first based on the X-ray source. Subsequently, a four-detector formation model was developed under relevant constraints. The model was then extended into a cement sheath density correction function and integrated into the original response formula of the four detectors concerning the counting rate. Finally, a new forward equation for X-ray cased-hole logging parameters of the four detectors was established. For the inversion problem of cased-hole logging parameters, Differential Evolution (DE) algorithm was employed to find the optimal values. The proposed forward and inverse methods for X-ray cased-hole logging parameters were applied to simulation examples and a practical case, which yielded satisfactory results. This method can effectively capture the geological characteristics and monitor the changes in casing and cement sheath, which offers significant implications for subsequent geological exploration.

关键词： X-ray source Cased-hole logging parameters Forward modeling Data inversion

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modeling Marronage: GIS Heuristics of Refuge Affordances in Colonial St. Croix

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JOURNAL OF ARCHAEOLOGICAL METHOD AND THEORY 2025年第1期32卷 1-30页

作者： Kohut, Lauren E. Wernke, Steven A. Dunnavant, Justin Winthrop Univ Dept Chem Phys Geol & Environm Rock Hill SC 29730 USA Vanderbilt Univ Dept Anthropol Nashville TN USA Univ Calif Los Angeles Dept Anthropol Los Angeles CA USA

On the Caribbean island of St. Croix, archival documents reference settlements of runaway enslaved Africans in the mountainous range known as Maroon Ridge. These settlements provide an important record of Afro-Atlantic resistance to enslavement. However, as both intentionally secluded and ephemeral places of refuge, these maroon settlements are difficult to locate in the archaeological record. Geospatial modeling provides one avenue for understanding African geographies of resistance. Building on prior geospatial modeling efforts, this paper uses a GIS-based multicriteria suitability analysis to characterize the shifting affordances of marronage on Danish colonial St. Croix across the second half of the eighteenth century. By considering how the island landscape "looked" to those seeking refuge, we trace how possibilities for refuge were distributed through space and over time. In this paper, we develop affordance heuristics to model refuge using digitized historic maps and publicly available LiDAR data. The resulting model suggests shifting maroon refugia sites over time and demonstrates how geospatial approaches, paired with historical archives, can model historic affordances across time.

关键词： Caribbean Slavery Suitability analysis Circuit analysis LiDAR GIS Colonialism

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modeling Self-Pressurization and Spray Bar Pressure Control of a Cryogenic Storage Tank in Normal Gravity

Modeling Self-Pressurization and Spray Bar Pressure Control ...

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AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2025

作者： Soriano, Steven Kartuzova, Olga Kassemi, Mohammad Hauser, Daniel Fluid and Cryogenic Systems Branch HX5 and NASA Glenn Research Center ClevelandOH44135 United States Case Western Reserve University and NASA Glenn Research Center ClevelandOH44135 United States Fluid and Cryogenic Systems Branch NASA Glenn Research Center ClevelandOH44135 United States

ISBN: (数字)9781624107238

ISBN: (纸本)9781624107238

This paper presents computational fluid dynamics (CFD) models for simulating selfpressurization and spray-bar pressure control processes in a large-scale liquid hydrogen storage tank under normal gravity conditions. For self-pressurization, the model employs the kinetics-based Schrage equation alongside the volume-of-fluid (VOF) method to account for interfacial mass transfer. The CFD predictions of pressure and temperature are compared with experimental data from the Multipurpose Hydrogen Test Bed (MHTB) experiment, and the predicted interfacial mass transfer rates are also presented. A CFD model simulating pressure control using a spray bar has also been developed. An Eulerian-Lagrangian approach models the interactions between discrete droplets and the continuous ullage (vapor) phase. The spray model is coupled with the VOF method by tracking droplets in the ullage and removing them when they reach the liquid interface. The T-sat model calculates droplet-ullage heat and mass transfer, where droplets warm up to the saturation temperature corresponding to the ullage vapor pressure before evaporating while remaining at the saturation temperature. The evolution of tank pressure, vapor temperature, and liquid temperature predicted by the CFD model is validated against data from the MHTB spray-bar mixing experiment. Overall, the CFD models agree with experimental data, demonstrating their capability to simulate self-pressurization and pressure control processes in large-scale cryogenic storage tanks. These models can be valuable tools for designing and optimizing cryogenic fluid management systems in future applications. © 2025, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Pressurization

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modeling spectral effects of colored BIPV modules on vertical façades

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SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS 2025年 75卷

作者： Sanz-Saiz, Carlos Silva, Jose Pedro Marcos, Ana Polo, Jesus CIEMAT Photovolta Solar Energy Unit Avda Complutense 40 Madrid 28040 Spain UPM Dept Construct & Technol Architecture ETSAM Madrid Spain

Building-integrated photovoltaics (BIPV) allows renewable energy generation within urban environments. The development of appealing BIPV products, such as colored modules, favors BIPV deployment. However, little attention has been given to the influence of the mounting conditions (i.e., inclination, orientation) and the color choice on the spectral effects that affect the power output of such BIPV installations. As a novelty, this work presents a method suitable for evaluating the spectral effects undergone by colored modules installed in vertical fa & ccedil;ades as a function of both fa & ccedil;ade orientation and module color. This method has been applied to three colored crystalline silicon (c-Si) BIPV modules (anthracite, terracotta, and green) for vertical installations in Madrid (Spain) under representative albedo conditions and compared with the results of three spectral models designed for conventional photovoltaic systems (SAPM, First Solar, Caballero). Results suggested that while the effective transmittance (and consequently the power output) was affected by fa & ccedil;ade orientation and color choice, the latter had a negligible influence on spectral mismatch effects. In contrast, fa & ccedil;ade orientation was a determinant for predicting some spectral losses throughout the year, which conventional spectral models cannot account for.

关键词： Building-integrated photovoltaics (BIPV) Vertical fa & ccedil ades Colored modules Irradiance modeling Spectral mismatch factor

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Assessment of the CTF subchannel code for modeling a large-break loss-of-coolant accident reflood transient

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ANNALS OF NUCLEAR ENERGY 2025年 210卷

作者： Salko, Robert Wysocki, Aaron Hizoum, Belgacem Capps, Nathan Oak Ridge Natl Lab 1 Bethel Valley Rd Oak Ridge TN 37830 USA

With increased industry interest in extending reactor operating cycles, the Nuclear Energy Advanced modeling and Simulation (NEAMS) program has been investigating the behavior of high-burnup fuel during design basis accidents such as the large-break loss-of-coolant accident (LBLOCA) with consideration for risk of fuel fragmentation, relocation, and dispersal (FFRD). As part of that activity, the NEAMS subchannel thermal/ hydraulics (T/H) code, CTF, is being used for modeling of LBLOCA and to determine the impact of subchannel resolution on results. Although CTF includes a wide range of models for LBLOCA conditions, the code has not been used for this application while maintained at Oak Ridge National Laboratory (ORNL) until now. Therefore, in this work, a preliminary assessment of several of these models was performed using openly available reflood experimental data from the Flooding Experiments in Blocked Arrays (FEBA) tests. One coarse mesh and one fine mesh model were set up in CTF for high and low flooding rate tests performed in the unblocked FEBA facility. A coarse TRACE model was set up to be as consistent as possible with the coarse CTF model to allow for code-to-code benchmarking. The assessment shows a tendency of the codes to over-predict peak cladding temperature (PCT) near the top of the bundle and to quench early. Advanced spacer grid models were shown to improve upper bundle predictions in CTF. The resolved CTF model over-predicted PCT by a larger degree in the center channels in the low-flooding rate test, and it is believed that the radiative heat transfer model, which was not used in this study, may be needed to correct this over-prediction. Finally, this work demonstrates the importance of the droplet model in determining quench time and vapor temperature and PCT prediction, which necessitates a more in-depth validation of these models in the future.

关键词： LOCA CTF FEBA ORNL

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modeling studies of dust/gas non-thermal equilibrium in the Martian atmosphere

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ICARUS 2025年 429卷

作者： Haberle, Robert M. Kahre, Melinda A. Bertrand, Tanguy Wolff, Michael J. NASA Ames Res Ctr Space Sci & Astrobiol Div MS 245-3 Moffett Field CA 94035 USA NASA Ames Res Ctr Space Sci & Astrobiol Div MS 245-3 Moffett Field CA 94035 USA Univ Paris Diderot Sorbonne Univ Univ PSL CNRSObserv ParisLab Etudes Spatiales & Instrumen 5 Pl Jules Janssen F-92195 Meudon France Space Sci Inst 4750 Walnut StSuite 205 Boulder CO 80301 USA

We discuss and implement the physics of dust-gas non-equilibrium processes into 1-D radiative-convective and 3D climate models to assess at what altitude dust and gas temperatures in the Martian atmosphere diverge and to what extent it affects the thermal structure, dynamics, and transport capabilities of the upper atmosphere. As found in an earlier paper by Goldenson et al. (2008), we find (using a different approach) that dust and gas temperatures diverge above 40 km as collisions between dust particles and gas molecules are too infrequent to equilibrate these two components. With our 1-D model we show that when dust-gas non-equilibrium physics is included, gas temperatures above 40 km cool and heating rates are reduced. The magnitude of the effect depends mostly on the size and abundance of the dust particles and is proportional to each. With our 3-D model we show that this physics is important mainly during times of intense dust lifting events such as local rocket storms, or regional or global storms when dust quickly penetrates to high altitudes and particle sizes can be somewhat larger at least initially. During such times upper atmosphere temperatures cool, wind systems are weakened, and vertical and meridional transport is diminished when compared to simulation assuming thermal equilibrium.

关键词： Mars Planetary atmospheres Dust physics Radiative transfer Atmospheric science Collisional processes

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Urban Air Mobility demand forecasting: modeling evidence from the case study of Milan (Italy)

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EUROPEAN TRANSPORT RESEARCH REVIEW 2025年第1期17卷 1-17页

作者： Coppola, Pierluigi De Fabiis, Francesco Silvestri, Fulvio Politecn Milan Dept Mech Engn Via G La Masa 1 I-20156 Milan Italy

This paper presents the results of a demand forecasting study about the introduction of Urban Air Mobility (UAM) services in the metropolitan area of Milan (Italy). Demand forecasting is based on random utility mode choice models, which include factors related to the individuals' perception of vertical take-off/landing and low altitude flying over urbanized areas. The use cases of UAM services include airport shuttles, intercity air connections, and "air-taxis", i.e., UAM services for short-trips within the metropolitan area. Several scenarios have been considered based on the number of access points ("vertiports") and UAM fare levels. The results indicate that airport shuttles have a modal share of trips to/from airports (for both business and leisure) in a range of 2-5%. They resulted to be more attractive than air-taxis, which have a modal share in a range of 1-3%. Furthermore, the probability of choosing UAM services for intercity travels decreases with the distance and the time required for access/egress to/from the vertiports, whose catchment areas are dependent on the level of service provided by competing modes (notably the presence of good railway and highway connections).

关键词： UAM eVTOL Vertiports Discrete choice analysis Mode choice models Urban mobility Airport shuttles

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Lightweight Neural Data Sequence modeling by Scale Causal Blocks

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IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS 2025年第4期E108D卷 392-402页

作者： Akutsu, Hiroaki Arai, Ko Hitachi Ltd R&D Grp Yokohama 2440817 Japan

Autoregressive probability estimation of data sequences is a fundamental task in deep neural networks and has been widely used in applications such as data compression and generation. Since it is a sequential iterative process due to causality, there is a problem that its process is slow. One way to achieve high throughput is multiplexing on a GPU. To maximize the throughput of inference processing within the limited resources of the GPU, it is necessary to avoid the increase in computational complexity associated with deeper layers and to reduce the required memory consumption at higher multiplexing. In this paper, we propose Scale Causal Blocks (SCBs), which are basic components of deep neural networks that aim to significantly reduce the computational and memory cost compared to conventional techniques. Evaluation results show that the proposed method is one order of magnitude faster than a conventional computationally optimized Transformer-based method while maintaining comparable accuracy, and also shows better learning convergence.

关键词： probability estimation GPU computational effeciency neural networks

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modeling COVID-19 dynamics in the Basque Country: characterizing population immunity profile from 2020 to 2022

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BMC INFECTIOUS DISEASES 2025年第1期25卷 1-24页

作者： Naffeti, Bechir Ounissi, Zeineb Srivastav, Akhil Kumar Stollenwerk, Nico Van-Dierdonck, Joseba Bidaurrazaga Aguiar, Maira Basque Ctr Appl Math Bilbao Bizkaia Spain Basque Hlth Dept Publ Hlth Bilbao Basque Country Spain Basque Fdn Sci Ikerbasque Bilbao Spain

BackgroundCOVID-19, caused by SARS-CoV-2, has spread globally, presenting a significant public health challenge. Vaccination has played a critical role in reducing severe disease and deaths. However, the waning of immunity after vaccination and the emergence of immune-escape variants require the continuation of vaccination efforts, including booster doses, to maintain population immunity. This study models the dynamics of COVID-19 in the Basque Country, Spain, aiming to characterize the population's immunity profile and assess its impact on the severity of outbreaks from 2020 to *** SIR/DS model was developed to analyze the interplay of virus-specific and vaccine-induced immunity. The model includes three levels of immunity, with boosting effects from reinfection and/or vaccination. It was validated using empirical daily case data from the Basque Country. The model tracks shifts in immunity status and their effects on disease dynamics over *** COVID-19 epidemic in the Basque Country progressed through three distinct phases, each shaped by dynamic interactions between virus transmission, public health interventions, and vaccination efforts. The initial phase was marked by a rapid surge in cases, followed by a decline due to strict public health measures, with a seroprevalence of 1.3%\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$1.3\%$$\end{document}. In the intermediate phase, multiple smaller outbreaks emerged as restrictions were relaxed and new variants, such as Alpha and Delta, appeared. During this period, reinfection rates reached 20%\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$

关键词： Epidemiology COVID-19 modeling Data analysis Vaccination Immunity boosting Immunity profile

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modeling proppant transport and settlement in 3D fracture networks in geothermal reservoirs

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GEOTHERMICS 2025年 125卷

作者： Liu, Baohua Kumar, Dharmendra Ghassemi, Ahmad Univ Oklahoma Mewbourne Sch Petr & Geol Engn Norman OK 73019 USA

In this paper, we develop an efficient proppant transport model using the Eulerian-Eulerian approach for simulating proppant transport in fractures and 3D fracture networks in geothermal reservoirs. The proposed model accounts for proppant settling, pack/bed formation, bridging/screenout, proppant concentration effect, fracture wall effect, and the transition from Poiseuille flow (fracture channel) to Darcy flow (proppant pack). Notably, the heat transfer process and its impact on proppant transport are also considered-a facet often overlooked in previous proppant transport models. A three-dimensional displacement discontinuity method (3D DDM) that incorporates the stress shadow effect is employed to generate the fracture geometry. The governing equations for slurry flow, proppant transport, and heat transfer are discretized and solved using the finite volume method (FVM). The model is verified against analytical solutions and published experimental data, demonstrating good agreement with these references. To demonstrate the proposed model, we applied it to both low- temperature (depleted hydrocarbon wells) and high-temperature (dry hot rocks) enhanced geothermal systems (EGS). The simulation results highlight the significant influence of reservoir temperature on proppant transport and settlement in a reservoir environment. Heating of the slurry by higher temperature reservoir rocks reduces fluid viscosity and accelerates proppant settling, thereby shortening the transport distance and reducing the coverage area of the proppant. Both ultra-light and micro-proppant are effective in mitigating proppant settlement in enhanced geothermal systems. However, proppant is susceptible to bridging at fracture intersections, where the fracture widths are narrower due to more pronounced stress shadow effects in these areas. Consequently, the use of micro-proppant could offer substantial benefits over ultra-light proppant in enhancing proppant coverage area in enhanced geothermal

关键词： Hydraulic fracturing Proppant transport Gravitational settling Heat transfer Enhanced geothermal systems

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