898 research outputs found
A kinematically exact finite element formulation of elastic-plastic curved beams
A finite element, large displacement formulation of static elastic-plastic analysis of slender arbitrarily curved planar beams is presented. Non-conservative and dynamic loads are sit present not included. The Bernoulli hypothesis of plane cross-sections is assumed and the effect of hear strains is neglected. Exact non-linear kinematic equations of curved beams, derived by Reissner are incorporated into;a generalized principle of virtual work through Lagrangian multipliers. The only function that has to be interpolated in the finite element implementation is the rotation of the centroid axis of a beam. This is an important advantage over other classical displacement approaches since the field consistency problem and related locking phenomena do not arise. Numerical examples, comprising elastic and elastic-plastic, curved and straight beams, at large displacements and rotations, show very nice computational and accuracy characteristics of the present family of finite elements. The comparisons with other published results very clearly show the superior performance of the present elements. (C) 1998 Elsevier Science Ltd. All rights reserved
What if we have Meta GPT? From Content Singularity to Human-Metaverse Interaction in AIGC Era
The global metaverse development is facing a "cooldown moment", while the
academia and industry attention moves drastically from the Metaverse to AI
Generated Content (AIGC) in 2023. Nonetheless, the current discussion rarely
considers the connection between AIGCs and the Metaverse. We can imagine the
Metaverse, i.e., immersive cyberspace, is the black void of space, and AIGCs
can simultaneously offer content and facilitate diverse user needs. As such,
this article argues that AIGCs can be a vital technological enabler for the
Metaverse. The article first provides a retrospect of the major pitfall of the
metaverse applications in 2022. Second, we discuss from a user-centric
perspective how the metaverse development will accelerate with AIGCs. Next, the
article conjectures future scenarios concatenating the Metaverse and AIGCs.
Accordingly, we advocate for an AI-Generated Metaverse (AIGM) framework for
energizing the creation of metaverse content in the AIGC era.Comment: 11 pages, 4 figure
A magnetic γ-Fe\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e3\u3c/sub\u3e@PANI@TiO\u3csub\u3e2\u3c/sub\u3e core–shell nanocomposite for arsenic removal \u3ci\u3evia\u3c/i\u3e a coupled visible-light-induced photocatalytic oxidation– adsorption process†
Arsenic polluted groundwater impairs human health and poses severe threats to drinking water supplies and ecosystems. Hence, an efficient method of simultaneous oxidation of As(III) to As(V), and removal of As(V) from water has triggered increasing attention. In this study, a magnetic γ-Fe2O3 core–shell heterojunction nanocomposite was synthesized by means of hydrothermal crystallization of TiO2 on the surface of the magnetic core–shell loaded with polyaniline (γ-Fe2O3@PANI@TiO2). As an efficient photocatalyst coupled with adsorption, γ-Fe2O3@PANI@TiO2 has a high light utilization and good adsorption capacity. Notably, the nanocomposite has excellent stability at various initial pH values with good reusability. Among the co-existing ions investigated, PO43- has the greatest competitive reaction. The photocatalytic oxidation of As(III) on γ-Fe2O3@PANI@TiO2 is dominated by the synergy of several active substances, with superoxide free radicals and photogenerated holes being the major players
Responsive and Personalized Web Layouts with Integer Programming
Over the past decade, responsive web design (RWD) has become the de facto standard for adapting web pages to a wide range of devices used for browsing. While RWD has improved the usability of web pages, it is not without drawbacks and limitations: designers and developers must manually design the web layouts for multiple screen sizes and implement associated adaptation rules, and its "one responsive design fits all"approach lacks support for personalization. This paper presents a novel approach for automated generation of responsive and personalized web layouts. Given an existing web page design and preferences related to design objectives, our integer programming -based optimizer generates a consistent set of web designs. Where relevant data is available, these can be further automatically personalized for the user and browsing device. The paper includes presentation of techniques for runtime adaptation of the designs generated into a fully responsive grid layout for web browsing. Results from our ratings-based online studies with end users (N = 86) and designers (N = 64) show that the proposed approach can automatically create high-quality responsive web layouts for a variety of real-world websites.Peer reviewe
A hysteretic multiscale formulation for nonlinear dynamic analysis of composite materials
This article has been made available through the Brunel Open Access Publishing Fund.A new multiscale finite element formulation
is presented for nonlinear dynamic analysis of heterogeneous
structures. The proposed multiscale approach utilizes
the hysteretic finite element method to model the microstructure.
Using the proposed computational scheme, the micro-basis functions, that are used to map the microdisplacement components to the coarse mesh, are only evaluated once and remain constant throughout the analysis procedure. This is accomplished by treating inelasticity at the micro-elemental level through properly defined hysteretic evolution equations. Two types of imposed boundary conditions are considered for the derivation of the multiscale basis functions, namely the linear and periodic boundary conditions. The validity of the proposed formulation as well as its computational efficiency are verified through illustrative numerical experiments
A full Eulerian finite difference approach for solving fluid-structure coupling problems
A new simulation method for solving fluid-structure coupling problems has
been developed. All the basic equations are numerically solved on a fixed
Cartesian grid using a finite difference scheme. A volume-of-fluid formulation
(Hirt and Nichols (1981, J. Comput. Phys., 39, 201)), which has been widely
used for multiphase flow simulations, is applied to describing the
multi-component geometry. The temporal change in the solid deformation is
described in the Eulerian frame by updating a left Cauchy-Green deformation
tensor, which is used to express constitutive equations for nonlinear
Mooney-Rivlin materials. In this paper, various verifications and validations
of the present full Eulerian method, which solves the fluid and solid motions
on a fixed grid, are demonstrated, and the numerical accuracy involved in the
fluid-structure coupling problems is examined.Comment: 38 pages, 27 figures, accepted for publication in J. Comput. Phy
The sequencing and interpretation of the genome obtained from a Serbian individual
Recent genetic studies and whole-genome sequencing projects have greatly
improved our understanding of human variation and clinically actionable genetic
information. Smaller ethnic populations, however, remain underrepresented in
both individual and large-scale sequencing efforts and hence present an
opportunity to discover new variants of biomedical and demographic
significance. This report describes the sequencing and analysis of a genome
obtained from an individual of Serbian origin, introducing tens of thousands of
previously unknown variants to the currently available pool. Ancestry analysis
places this individual in close proximity of the Central and Eastern European
populations; i.e., closest to Croatian, Bulgarian and Hungarian individuals
and, in terms of other Europeans, furthest from Ashkenazi Jewish, Spanish,
Sicilian, and Baltic individuals. Our analysis confirmed gene flow between
Neanderthal and ancestral pan-European populations, with similar contributions
to the Serbian genome as those observed in other European groups. Finally, to
assess the burden of potentially disease-causing/clinically relevant variation
in the sequenced genome, we utilized manually curated genotype-phenotype
association databases and variant-effect predictors. We identified several
variants that have previously been associated with severe early-onset disease
that is not evident in the proband, as well as variants that could yet prove to
be clinically relevant to the proband over the next decades. The presence of
numerous private and low-frequency variants along with the observed and
predicted disease-causing mutations in this genome exemplify some of the global
challenges of genome interpretation, especially in the context of understudied
ethnic groups.Comment: 18 pages, 2 figure
Diabetic Retinopathy in 2011: Further Insights From New Epidemiological Studies and Clinical Trials
10.2337/dc11-0225Diabetes Care3441066-1067DICA
A map of human cancer signaling
We conducted a comprehensive analysis of a manually curated human signaling network containing 1634 nodes and 5089 signaling regulatory relations by integrating cancer-associated genetically and epigenetically altered genes. We find that cancer mutated genes are enriched in positive signaling regulatory loops, whereas the cancer-associated methylated genes are enriched in negative signaling regulatory loops. We further characterized an overall picture of the cancer-signaling architectural and functional organization. From the network, we extracted an oncogene-signaling map, which contains 326 nodes, 892 links and the interconnections of mutated and methylated genes. The map can be decomposed into 12 topological regions or oncogene-signaling blocks, including a few ‘oncogene-signaling-dependent blocks' in which frequently used oncogene-signaling events are enriched. One such block, in which the genes are highly mutated and methylated, appears in most tumors and thus plays a central role in cancer signaling. Functional collaborations between two oncogene-signaling-dependent blocks occur in most tumors, although breast and lung tumors exhibit more complex collaborative patterns between multiple blocks than other cancer types. Benchmarking two data sets derived from systematic screening of mutations in tumors further reinforced our findings that, although the mutations are tremendously diverse and complex at the gene level, clear patterns of oncogene-signaling collaborations emerge recurrently at the network level. Finally, the mutated genes in the network could be used to discover novel cancer-associated genes and biomarkers
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