3,163 research outputs found
The concept of usage HRTSIM as a device for setting and certification of AVR
This paper presents the analysis of application Hybrid RealTime Power System Simulator (HRTSim), developed at National Research Tomsk Polytechnic University, as a device for setting and certification of automatic voltage regulators (AVR) for synchronous generators. The simulation results demonstrate that the proposed hardware-software complex (HSC) can be used for presented aim
Fast and Accurate Reduced-Order Modeling of a MOOSE-based Additive Manufacturing Model with Operator Learning
One predominant challenge in additive manufacturing (AM) is to achieve
specific material properties by manipulating manufacturing process parameters
during the runtime. Such manipulation tends to increase the computational load
imposed on existing simulation tools employed in AM. The goal of the present
work is to construct a fast and accurate reduced-order model (ROM) for an AM
model developed within the Multiphysics Object-Oriented Simulation Environment
(MOOSE) framework, ultimately reducing the time/cost of AM control and
optimization processes. Our adoption of the operator learning (OL) approach
enabled us to learn a family of differential equations produced by altering
process variables in the laser's Gaussian point heat source. More specifically,
we used the Fourier neural operator (FNO) and deep operator network (DeepONet)
to develop ROMs for time-dependent responses. Furthermore, we benchmarked the
performance of these OL methods against a conventional deep neural network
(DNN)-based ROM. Ultimately, we found that OL methods offer comparable
performance and, in terms of accuracy and generalizability, even outperform DNN
at predicting scalar model responses. The DNN-based ROM afforded the fastest
training time. Furthermore, all the ROMs were faster than the original MOOSE
model yet still provided accurate predictions. FNO had a smaller mean
prediction error than DeepONet, with a larger variance for time-dependent
responses. Unlike DNN, both FNO and DeepONet were able to simulate time series
data without the need for dimensionality reduction techniques. The present work
can help facilitate the AM optimization process by enabling faster execution of
simulation tools while still preserving evaluation accuracy.Comment: 28 pages, 18 figures, 4 table
First performance of the gems + gmos system. Part1. Imaging
During the commissioning of the Gemini MCAO System (GeMS), we had the
opportunity to obtain data with the Gemini Multi-Object Spectrograph (GMOS),
the most utilised instrument at Gemini South Observatory, in March and May
2012. Several globular clusters were observed in imaging mode that allowed us
to study the performance of this new and untested combination. GMOS is a
visible instrument, hence pushing MCAO toward the visible.We report here on the
results with the GMOS instruments, derive photometric performance in term of
Full Width Half Maximum (FWHM) and throughput. In most of the cases, we
obtained an improvement factor of at least 2 against the natural seeing. This
result also depends on the Natural Guide Star constellation selected for the
observations and we then study the impact of the guide star selection on the
FWHM performance.We also derive a first astrometric analysis showing that the
GeMS+GMOS system provide an absolute astrometric precision better than 8mas and
a relative astrometric precision lower than 50 mas.Comment: 13 pages, 11 figures, accepted for publication in MNRAS on March 23rd
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Ground failure along the New River caused by the October 1979 Imperial Valley earthquake sequence
We recognized a number of ground failures along the south bank of the New River north of Brawley, California, following the 15 October 1979 Imperial Valley, California, earthquake sequence. The zone includes a large pond and numerous sand boils, apparently caused by liquefaction, near the Del Rio Country Club. These ground failures, together with failures at the New River bridge west of Brawley and at Wiest Lake, form a discontinuous zone 10 km long. While this zone appears to coincide with the aftershocks following the 16 October 1979, M_L 5.8, Brawley earthquake (the largest aftershock of the Imperial Valley earthquake), a cause and effect relationship cannot be demonstrated. No evidence of tectonic surface faulting could be found
Patenting of University and Non-University Public Research Organisations in Germany: Evidence from Patent Applications for Medical Research Results
BACKGROUND: Patents are one of the most important forms of intellectual property. They grant a time-limited exclusivity on the use of an invention allowing the recuperation of research costs. The use of patents is fiercely debated for medical innovation and especially controversial for publicly funded research, where the patent holder is an institution accountable to public interest. Despite this controversy, for the situation in Germany almost no empirical information exists. The purpose of this study is to examine the amount, types and trends of patent applications for health products submitted by German public research organisations. METHODS/PRINCIPAL FINDINGS: We conducted a systematic search for patent documents using the publicly accessible database search interface of the German Patent and Trademark Office. We defined keywords and search criteria and developed search patterns for the database request. We retrieved documents with application date between 1988 and 2006 and processed the collected data stepwise to compile the most relevant documents in patent families for further analysis. We developed a rationale and present individual steps of a systematic method to request and process patent data from a publicly accessible database. We retrieved and processed 10194 patent documents. Out of these, we identified 1772 relevant patent families, applied for by 193 different universities and non-university public research organisations. 827 (47%) of these patent families contained granted patents. The number of patent applications submitted by universities and university-affiliated institutions more than tripled since the introduction of legal reforms in 2002, constituting almost half of all patent applications and accounting for most of the post-reform increase. Patenting of most non-university public research organisations remained stable. CONCLUSIONS: We search, process and analyse patent applications from publicly accessible databases. Internationally mounting evidence questions the viability of policies to increase commercial exploitation of publicly funded research results. To evaluate the outcome of research policies a transparent evidence base for public debate is needed in Germany
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