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multiresolution modeling of High-Latitude Ionospheric Electric Field Variability and Impact on Joule Heating Using SuperDARN Data

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JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS 2021年第9期126卷 e2021JA029196页

作者： Matsuo, Tomoko Fan, Minjie Shi, Xueling Miller, Caleb Ruohoniemi, J. Michael Paul, Debashis Lee, Thomas C. M. Univ Colorado Ann & HJ Smead Dept Aerosp Engn Sci Boulder CO 80309 USA Univ Calif Davis Dept Stat Davis CA 95616 USA Virginia Polytech Inst & State Univ Dept Elect & Comp Engn Blacksburg VA 24061 USA Univ Colorado Dept Appl Math Boulder CO 80309 USA

The most dynamic electromagnetic coupling between the magnetosphere and ionosphere occurs in the polar upper atmosphere. It is critical to quantify the electromagnetic energy and momentum input associated with this coupling as its impacts on the ionosphere and thermosphere system are global and major, often leading to considerable disturbances in near-Earth space environments. The current general circulation models of the upper atmosphere exhibit systematic biases that can be attributed to an inadequate representation of the Joule heating rate resulting from unaccounted stochastic fluctuations of electric fields associated with the magnetosphere-ionosphere coupling. These biases exist regardless of geomagnetic activity levels. To overcome this limitation, a new multiresolution random field modeling approach is developed, and the efficacy of the approach is demonstrated using Super Dual Auroral Radar Network (SuperDARN) data carefully curated for the study during a largely quiet 4-hour period on February 29, 2012. Regional small-scale electrostatic fields sampled at different resolutions from a probabilistic distribution of electric field variability conditioned on actual SuperDARN LOS observations exhibit considerably more localized fine-scale features in comparison to global large-scale fields modeled using the SuperDARN Assimilative Mapping procedure. The overall hemispherically integrated Joule heating rate is increased by a factor of about 1.5 due to the effect of random regional small-scale electric fields, which is close to the lower end of arbitrarily adjusted Joule heating multiplicative factor of 1.5 and 2.5 typically used in upper atmosphere general circulation models. The study represents an important step toward a data-driven ensemble modeling of magnetosphere-ionosphere-atmosphere coupling processes.

关键词： multiresolution modeling high-latitude ionospheric electric field variability Joule heating rate MCMC needlets SuperDARN

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multiresolution modeling of a Modular Building Design Process Based on Design Structure Matrix

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BUILDINGS 2023年第9期13卷 2330页

作者： Wang, Yu Bian, Suping Dong, Ling Li, Hongxian Nanjing Inst Technol Sch Architectural Engn Nanjing 211167 Peoples R China Nanjing Tech Univ Sch Architecture Nanjing 211816 Peoples R China Deakin Univ Sch Architecture & Built Environm Geelong Vic 3220 Australia

Currently, modular building is undergoing vigorous development in China, and has provided a significant advantage in many fields, but its quality is difficult to guarantee. The key is to improve the design process, shorten the development cycle, and enhance competitiveness. Therefore, it is necessary to establish and optimize the design process of modular buildings. This article was based on the DSM and adopted a parallel design to model the modular building design process. Based on this, the design process was analyzed and optimized to shorten the development cycle and reduce costs. At the same time, considering the differences in attributes between different stages of the modular building design process, a DSM model with different resolutions was constructed based on the content and interrelationships of modular building design. The schedule and cost of the design process were evaluated through simulation, the differences between different resolution models were compared, and a more reliable estimate of the schedule and cost of the design process was obtained. Considering the workload and difficulty of high-resolution modeling, an approximate estimation method based on low-resolution modeling was proposed to alleviate the dependence on high-resolution models and modeling costs to some extent, thereby effectively improving the predictability of the design process and providing necessary reference for product design management personnel.

关键词： modular buildings multiresolution modeling system simulation schedule assessment cost assessment

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The role of approximate morphisms in multiresolution modeling: Can we relax the strict lumpability requirements?

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JOURNAL OF DEFENSE modeling AND SIMULATION-APPLICATIONS METHODOLOGY TECHNOLOGY-JDMS 2018年第4期15卷 495-498页

作者： Zeigler, Bernard P. RTSync Corp Tucson AZ 85701 USA Arizona Ctr Integrat Modeling & Simulat Tucson AZ 85701 USA

To become the core development methodology of major defense-related simulation projects, multiresolution modeling needs more advances in basic theory and practice. In this note, we illustrate an approach to addressing issues relating to approximate morphisms (structure/behavior preservation relations) between pairs of models. Such issues include metrics for departure from strict lumpability, tying approximate satisfaction of structural conditions to the resulting behavioral error, and how to enhance the probability of creating good approximate morphisms by humans and artificial modelers.

关键词： multiresolution modeling abstraction resolution fidelity exact morphisms approximate morphisms performance-accuracy tradeoff

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MULTI-RESOLUTION modeling FOR ADAPTIVE UAV SERVICE SYSTEMS

MULTI-RESOLUTION MODELING FOR ADAPTIVE UAV SERVICE SYSTEMS

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Spring Simulation Conference (SpringSim)

作者： Zeigler, Bernard P. Kim, Doohwan Univ Arizona Elect & Comp Engn Tucson AZ 85721 USA RTSync Corp Phoenix AZ 85044 USA RTSync Corp Chandler AZ USA

ISBN: (纸本)9781510883888

With the advent of Unmanned Autonomous Vehicles (UAV), new kinds of systems of systems (SoS) that provide specific services may be on the horizon. We recognize that beyond basic technology requirements, such UAV-based service systems may be subject to a multiplicity of system engineering objectives. An all-inclusive model would be able to provide the basis for decision making in each of such categories as payload requirements, on-board-energy constraints, locations of depots/launch sites, and so on. multiresolution modeling helps us to construct a collection of partial models, each oriented to one or more objectives. In this paper, we discuss a modeling and Simulation methodology that is based on Discrete Event System Specification (DEVS) and System Entity Structure (SES). As implemented in the MS4 Me integrated development environment, it provides a practical approach to multiresolution model-based system design of UAV-based service systems.

关键词： Systems of systems multiresolution modeling unmanned autonomous vehicles adaptive sustainment systems DEVS Markov models

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Dystrophin's central domain forms a complex filament that becomes disorganized by in-frame deletions

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JOURNAL OF BIOLOGICAL CHEMISTRY 2018年第18期293卷 6637-6646页

作者： Delalande, Olivier Molza, Anne-Elisabeth Morais, Raphael Dos Santos Cheron, Angelique Pollet, Emeline Raguenes-Nicol, Celine Tascon, Christophe Giudice, Emmanuel Guilbaud, Marine Nicolas, Aurelie Bondon, Arnaud Leturcq, France Ferey, Nicolas Baaden, Marc Perez, Javier Roblin, Pierre Pietri-Rouxel, France Hubert, Jean-Francois Czjzek, Mirjam Le Rumeur, Elisabeth Univ Rennes Inst Genet & Dev Rennes CNRS UMR 6290 F-35000 Rennes France Synchrotron SOLEIL F-91190 St Aubin France Univ Paris Saclay CEA Saclay Lab Leon Brillouin CNRSUMR 12 CEA F-91191 Gif Sur Yvette France Sorbonne Univ UPMC INSERM UMRS 97CNRSFRE 3617Inst Myol F-75013 Paris France Univ Rennes Inst Sci Chim Rennes CNRS UMR 6226PRISM F-35000 Rennes France Grp Hosp Cochin Broca Hotel Dieu AP HP Lab Biochim & Genet Mol F-75014 Paris France Univ Paris XI CNRS UPR3251 Orsay France Univ Paris Diderot Sorbonne Paris Cite CNRS UPR9080 Paris France INRA Biopolymeres Interact & Assemblages F-44000 Nantes France UPMC Univ Paris 06 Sorbonne Univ F-75006 Paris France CNRS UMR 8227 Integrat Biol Marine Models F-29688 Roscoff France

Dystrophin, encoded by the DMD gene, is critical for maintaining plasma membrane integrity during muscle contraction events. Mutations in the DMD gene disrupting the reading frame prevent dystrophin production and result in severe Duchenne muscular dystrophy (DMD);in-frame internal deletions allow production of partly functional internally deleted dystrophin and result in less severe Becker muscular dystrophy (BMD). Many known BMD deletions occur in dystrophin's central domain, generally considered to be a monotonous rod-shaped domain based on the knowledge of spectrin family proteins. However, the effects caused by these deletions, ranging from asymptomatic to severe BMD, argue against the central domain serving only as a featureless scaffold. We undertook structural studies combining small-angle X-ray scattering and molecular modeling in an effort to uncover the structure of the central domain, as dystrophin has been refractory to characterization. We show that this domain appears to be a tortuous and complex filament that is profoundly disorganized by the most severe BMD deletion (loss of exons 45-47). Despite the preservation of large parts of the binding site for neuronal nitric oxide synthase (nNOS) in this deletion, computational approaches failed to recreate the association of dystrophin with nNOS. This observation is in agreement with a strong decrease of nNOS immunolocalization in muscle biopsies, a parameter related to the severity of BMD phenotypes. The structural description of the whole dystrophin central domain we present here is a first necessary step to improve the design of microdystrophin constructs toward the goal of a successful gene therapy for DMD.

关键词： dystrophin molecular docking muscular dystrophy nitric oxide synthase small-angle X-ray scattering (SAXS) Becker muscular dystrophy dystrophin central domain multiresolution modeling

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A Multiscale Approach for Geologically and Flow Consistent modeling

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TRANSPORT IN POROUS MEDIA 2018年第1期124卷 237-261页

作者： Tahmasebi, Pejman Kamrava, Serveh Univ Wyoming Dept Petr Engn Laramie WY 82071 USA

Subsurface geological models are usually constructed on high-resolution grids in a way that various complexities and heterogeneities are depicted properly. Such models, however, cannot be used directly in the current flow simulators, as they are tied with high computational cost. Thus, using upscaling, by which one can produce flow consistent models that can alleviate the computational burden of flow simulators, is inevitable. Although the upscaling methods are able to reproduce the flow responses, they might not retain the initial geological assumptions. The reservoir models are initially constructed on uniform and high-resolution grids and then, if necessary, are upscaled to be used for flow simulations. A subsurface modeling approach that not only preserves the geological heterogeneity but also provides models that can be used, straight or with a small level of upscaling, in the flow simulators is desirable. In this paper, a new multiresolution method based on (1) the importance of conditioning well data and (2) being geologically and flow consistent is presented. This method discretizes the initial model into several regions based on the available data. Then, the initial assumed geological model is converted into, for example, various high- and low-resolution models. Next, the high-resolution model is used for regions with high-quality data (e.g., well locations), while the low-resolution model is used for the remaining areas. Finally, the patterns of these areas are interlocked, which result in a multiresolution geologically and flow consistent subsurface model. The accuracy of this method is demonstrated using two-phase flow simulation on four complex subsurface systems. The results indicate that the same flow responses, in a much less time, are reproduced using the multiscale models. The speed-up factor gained using the proposed method is also several orders of magnitude.

关键词： Two-phase flow multiresolution modeling Geological model SPE-10 Data assimilation

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MULTI-RESOLUTION modeling FOR ADAPTIVE UAV SERVICE SYSTEMS

MULTI-RESOLUTION MODELING FOR ADAPTIVE UAV SERVICE SYSTEMS

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Simulation Multi-Conference

作者： Bernard P. Zeigler Doohwan Kim RTSync Corp University of Arizona RTSync Corp Chandler AZ USA

关键词： Systems of systems multiresolution modeling Unmanned autonomous vehicles Adaptive sustainment systems DEVS markov models

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View-Dependent multiresolution modeling on the GPU

View-Dependent Multiresolution Modeling on the GPU

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17th International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision

作者： Ripolles, Oscar Gumbau, Jesus Chover, Miguel Ramos, Francisco Puig-Centelles, Anna Univ Jaume 1 LSI Dept Castellon de La Plana Spain

ISBN: (纸本)9788086943930

For more than a decade, researchers working on level-of-detail techniques have oriented their efforts toward developing better frameworks and adapting their solutions to new hardware. Nevertheless, we believe there is still a gap for efficient yet simple multiresolution models that fully exploit the potential of current GPUs. In this paper we present a level-of-detail framework based on moving the extraction process from updating indices to updating vertices. This feature enables us to perform culling and geomorphing on a vertex basis. Furthermore, it simplifies the update of indices to eliminate degenerate information. The model is capable of offering both uniform and variable resolution and to achieve the latter, a silhouette-based criterion has been included. Finally, we would like to highlight that the model is completely integrated in the GPU and no CPU/GPU communication is necessary once all the information is correctly loaded in hardware memory.

关键词： multiresolution modeling View-dependent Silhouette-preserving Shader Model 4.0

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Volume and Normal Field Based Simplification of Polygonal Models

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JOURNAL OF INFORMATION SCIENCE AND ENGINEERING 2013年第2期29卷 267-279页

作者： Hussain, Muhammad King Saud Univ Coll Comp & Informat Sci Dept Comp Sci Riyadh 11451 Saudi Arabia

In automatic decimation of polygonal models, the measure of geometric fidelity plays the key role. Among the existing measures, volume based error measure results in better quality approximations whereas the one based on normal field variation better preserves salient features. We exploit both volume and normal field to develop a more reliable and efficient two phase greedy algorithm. In the first phase, the priority of each vertex is defined using the normal field variation across its one-ring neighborhood. In the second phase, the desired number of vertices is removed according to their priorities. Once a vertex is a candidate for removal, it is eliminated by collapsing an outgoing half-edge that is selected by using the measure of geometric fidelity based on volume loss. Subjective and objective comparisons validate that the proposed algorithm not only has better speed-quality trade-off but also consumes less memory space and keeps visually important features even after drastic simplification in a better way than the similar state-of-the-art best algorithms. This method is useful for applications where computing coordinates and/or attributes other than those attached to the original vertices is not allowed by the application and the focus is on both speed and quality of LODs.

关键词： polygonal models polygonal simplification LOD modeling multiresolution modeling half-edge-collapse

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Design, analysis and additive manufacturing of porous structures for biocompatible micro-scale scaffolds

Design, analysis and additive manufacturing of porous struct...

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1st CIRP Conference on BioManufacturing (CIRP-BioM)

作者： Podshivalov, Lev Gomes, Cynthia M. Zocca, Andrea Guenster, Jens Bar-Yoseph, Pinhas Fischer, Anath Univ Paris 06 Lab Jacques Louis Lions F-75000 Paris France

Advancements in the fields of biocompatible materials, manufacturing processes, computational methods and medicine have led to the emergence of a new field: micro-scale scaffolds for bone replacement and regeneration. Yet most such scaffolds produced today are characterized by very basic geometry, and their microstructure differs greatly from that of the actual tissue they are intended to replace. In this paper, we propose a novel approach for generating micro-scale scaffolds based on processing actual micro-CT images and then reconstructing a highly accurate geometrical model. This model is manufactured by means of a state-of-the-art 3D additive manufacturing process from biocompatible materials. At the micro-scale level, these scaffolds are very similar to the original tissue, thus interfacing better with the surrounding tissue and facilitating more efficient rehabilitation for the patient. Moreover, the approach facilitates the design and manufacture of patient-specific scaffolds which can copy patients' exact structural and mechanical characteristics, taking into account their physical condition and medical history. By means of multi-resolution volumetric modeling methods, scaffold porosity can also be adapted according to specific mechanical requirements. The process of designing and manufacturing micro-scale scaffolds involves five major stages: (a) building a volumetric multi-resolution model from micro-CT images;(b) generation of surface geometric model in STL format;(c) additive manufacturing of the scaffold;(d) scaffold shape verification relative to the geometric design;and (e) verification of mechanical properties through finite element analysis. In this research, all the proposed stages of the approach were tested. The input included micro-CT scans of porous ceramic structure, which is quite similar to commercial porous scaffolds. The results show that the proposed method is feasible for design and manufacture of micro-scale scaffolds. (C) 2013 The Auth

关键词： micro-scale bone scaffolds additive manufacturing multiscale FEA ceramics multiresolution modeling

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