1,865 research outputs found
The Bohemian Club: An Empirical Investigation of the Power Elite
Articlehttp://deepblue.lib.umich.edu/bitstream/2027.42/97015/1/UMURF-Issue02_2005-BKamal.pd
Atomistic Line Graph Neural Network for Improved Materials Property Predictions
Graph neural networks (GNN) have been shown to provide substantial
performance improvements for representing and modeling atomistic materials
compared with descriptor-based machine-learning models. While most existing GNN
models for atomistic predictions are based on atomic distance information, they
do not explicitly incorporate bond angles, which are critical for
distinguishing many atomic structures. Furthermore, many material properties
are known to be sensitive to slight changes in bond angles. We present an
Atomistic Line Graph Neural Network (ALIGNN), a GNN architecture that performs
message passing on both the interatomic bond graph and its line graph
corresponding to bond angles. We demonstrate that angle information can be
explicitly and efficiently included, leading to improved performance on
multiple atomistic prediction tasks. We use ALIGNN models for predicting 52
solid-state and molecular properties available in the JARVIS-DFT, Materials
project, and QM9 databases. ALIGNN can outperform some previously reported GNN
models on atomistic prediction tasks by up to 85 % in accuracy with better or
comparable model training speed
Graphics Performance Benchmarks: Summary Report
Report on study of seven different benchmark software systems viewing the parameters and configurations of graphics systems
Immunomodulation of Autoimmune Arthritis by Herbal CAM
Rheumatoid arthritis (RA) is a debilitating autoimmune disease of global prevalence. The disease is characterized by synovial inflammation leading to cartilage and bone damage. Most of the conventional drugs used for the treatment of RA have severe adverse reactions and are quite expensive. Over the years, increasing proportion of patients with RA and other immune disorders are resorting to complementary and alternative medicine (CAM) for their health needs. Natural plant products comprise one of the most popular CAM for inflammatory and immune disorders. These herbal CAM belong to diverse traditional systems of medicine, including traditional Chinese medicine, Kampo, and Ayurvedic medicine. In this paper, we have outlined the major immunological pathways involved in the induction and regulation of autoimmune arthritis and described various herbal CAM that can effectively modulate these immune pathways. Most of the information about the mechanisms of action of herbal products in the experimental models of RA is relevant to arthritis patients as well. The study of immunological pathways coupled with the emerging application of genomics and proteomics in CAM research is likely to provide novel insights into the mechanisms of action of different CAM modalities
Performance assessment of lower VHF band for short‐range communication and geolocation applications
The focus of this paper is to characterize near‐ground wave propagation in the lower very high frequency (VHF) band and to assess advantages that this frequency band offers for reliable short‐range low‐data rate communications and geolocation applications in highly cluttered environments as compared to conventional systems in the microwave range. With the advent of palm‐sized miniaturized VHF antennas, interest in low‐power and low‐frequency communication links is increasing because (1) channel complexity is far less in this frequency band compared to higher frequencies and (2) significant signal penetration through/over obstacles is possible at this frequency. In this paper, we quantify the excess path loss and small‐scale fading at the lower VHF and the 2.4 GHz bands based on short‐range measurements in various environments. We consider indoor‐to‐indoor, outdoor‐to‐indoor, and non‐line‐of‐sight outdoor measurements and compare the results with measurements at higher frequencies which are used in conventional systems (i.e., 2.4 GHz). Propagation measurements at the lower VHF band are carried out by using an electrically small antenna to assess the possibility of achieving a miniaturized, mobile system for near‐ground communication. For each measurement scenario considered, path loss and small‐scale fading are characterized after calibrating the differences in the systems used for measurements at different frequencies, including variations in antenna performance.Key PointsLow VHF has favorable short‐range characteristics and low signal distortionPenetration through many layers of building walls is possible at low VHFNovel miniaturized VHF antennas with reasonable performance have been designedPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111943/1/rds20240.pd
On the redundancy in large material datasets: efficient and robust learning with less data
Extensive efforts to gather materials data have largely overlooked potential
data redundancy. In this study, we present evidence of a significant degree of
redundancy across multiple large datasets for various material properties, by
revealing that up to 95 % of data can be safely removed from machine learning
training with little impact on in-distribution prediction performance. The
redundant data is related to over-represented material types and does not
mitigate the severe performance degradation on out-of-distribution samples. In
addition, we show that uncertainty-based active learning algorithms can
construct much smaller but equally informative datasets. We discuss the
effectiveness of informative data in improving prediction performance and
robustness and provide insights into efficient data acquisition and machine
learning training. This work challenges the "bigger is better" mentality and
calls for attention to the information richness of materials data rather than a
narrow emphasis on data volume.Comment: Main text: 10 pages, 2 tables, 5 figures. Supplemental information:
29 pages, 1 table, 23 figure
Computational Approaches for Modeling Power Consumption on an Underwater Flapping Fin Propulsion System
The last few decades have led to the rise of research focused on propulsion
and control systems for bio-inspired unmanned underwater vehicles (UUVs), which
provide more maneuverable alternatives to traditional UUVs in underwater
missions. Propulsive efficiency is of utmost importance for flapping-fin UUVs
in order to extend their range and endurance for essential operations. To
optimize for different gait performance metrics, we develop a non-dimensional
figure of merit (FOM), derived from measures of propulsive efficiency, that is
able to evaluate different fin designs and kinematics, and allow for comparison
with other bio-inspired platforms. We create and train computational models
using experimental data, and use these models to predict thrust and power under
different fin operating states, providing efficiency profiles. We then use the
developed FOM to analyze optimal gaits and compare the performance between
different fin materials. These comparisons provide a better understanding of
how fin materials affect our thrust generation and propulsive efficiency,
allowing us to inform control systems and weight for efficiency on an inverse
gait-selector model.Comment: 9 pages, 8 figures, conferenc
Recent progress in the JARVIS infrastructure for next-generation data-driven materials design
The Joint Automated Repository for Various Integrated Simulations (JARVIS)
infrastructure at the National Institute of Standards and Technology (NIST) is
a large-scale collection of curated datasets and tools with more than 80000
materials and millions of properties. JARVIS uses a combination of electronic
structure, artificial intelligence (AI), advanced computation and experimental
methods to accelerate materials design. Here we report some of the new features
that were recently included in the infrastructure such as: 1) doubling the
number of materials in the database since its first release, 2) including more
accurate electronic structure methods such as Quantum Monte Carlo, 3) including
graph neural network-based materials design, 4) development of unified
force-field, 5) development of a universal tight-binding model, 6) addition of
computer-vision tools for advanced microscopy applications, 7) development of a
natural language processing tool for text-generation and analysis, 8) debuting
a large-scale benchmarking endeavor, 9) including quantum computing algorithms
for solids, 10) integrating several experimental datasets and 11) staging
several community engagement and outreach events. New classes of materials,
properties, and workflows added to the database include superconductors,
two-dimensional (2D) magnets, magnetic topological materials, metal-organic
frameworks, defects, and interface systems. The rich and reliable datasets,
tools, documentation, and tutorials make JARVIS a unique platform for modern
materials design. JARVIS ensures openness of data and tools to enhance
reproducibility and transparency and to promote a healthy and collaborative
scientific environment
Mediators of Inflammation-Induced Bone Damage in Arthritis and Their Control by Herbal Products
Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the synovial joints leading to bone and cartilage damage. Untreated inflammatory arthritis can result in severe deformities and disability. The use of anti-inflammatory agents and biologics has been the mainstay of treatment of RA. However, the prolonged use of such agents may lead to severe adverse reactions. In addition, many of these drugs are quite expensive. These limitations have necessitated the search for newer therapeutic agents for RA. Natural plant products offer a promising resource for potential antiarthritic agents. We describe here the cellular and soluble mediators of inflammation-induced bone damage (osteoimmunology) in arthritis. We also elaborate upon various herbal products that possess antiarthritic activity, particularly mentioning the specific target molecules. As the use of natural product supplements by RA patients is increasing, this paper presents timely and useful information about the mechanism of action of promising herbal products that can inhibit the progression of inflammation and bone damage in the course of arthritis
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