1,794 research outputs found
Combination of Partial Stochastic Linearization and Karhunen-Loeve Expansion to Design Coriolis Dynamic Vibration Absorber
Coriolis dynamic vibration absorber is a device working in nonlinear zone. In stochastic design of this device, the Monte Carlo simulation requires large computation time. A simplified model of the system is built to retain the most important nonlinear term, the Coriolis damping of the dynamic vibration absorber. Applying the full equivalent linearization technique to the simplified model is inaccurate to describe the nonlinear behavior. This paper proposes a combination of partial stochastic linearization and Karhunen-Loeve expansion to solve the problem. The numerical demonstration of a ropeway gondola induced by wind load is presented. A design example based on the partial linearization supports the advantage of the proposed approach
Amplification of useful vibration using on-off damping
This paper points out how much useful vibration can be extracted from a base-excited oscillator, which is controlled by the on-off electrical damping. We study the class of on-off electrical damping controller, which switches the damping level from high to low and back at fixed times every quarter of period. The problem reduces to the maximization of a single-variable function. This result can open the new direction to amplify the useful vibration using controllable dampings
Bacillus odysseyi isolate
The present invention relates to discovery and isolation of a biologically pure culture of a Bacillus odysseyi isolate with high adherence and sterilization resistant properties. B. odysseyi is a round spore forming Bacillus species that produces an exosporium. This novel species has been characterized on the basis of phenotypic traits, 16S rDNA sequence analysis and DNA-DNA hybridization. According to the results of these analyses, this strain belongs to the genus Bacillus and the type strain is 34hs-1.sup.T (=ATCC PTA-4993.sup.T=NRRL B-30641.sup.T=NBRC 100172.sup.T). The GenBank accession number for the 16S rDNA sequence of strain 34hs-1.sup.T is AF526913
Application of the ATP assay to rapidly assess cleanliness of spacecraft surfaces: a path to set a standard for future missions
Is there more room to negotiate with the IMF on fiscal policy?
This repository item contains a working paper from the Boston University Global Economic Governance Initiative. The Global Economic Governance Initiative (GEGI) is a research program of the Center for Finance, Law & Policy, the Frederick S. Pardee Center for the Study of the Longer-Range Future, and the Frederick S. Pardee School of Global Studies. It was founded in 2008 to advance policy-relevant knowledge about governance for financial stability, human development, and the environment.During the 1980s the IMF emerged as a global âbad cop,â demanding harsh austerity measures in countries faced with debt problems. Has the Great Recession changed all that? Is there more room to negotiate with the Fund on fiscal policy? The answer is yes. If we take a close look at what the IMF researchers say and what its most influential official reports proclaim, then we can see that there has been a more âKeynesianâ turn at the Fund. This means that today one can find arguments for less austerity, more growth measures and a fairer social distribution of the burden of fiscal sustainability. The IMF has experience a major thaw of its fiscal policy doctrine and wellâinformed member states can use this to their advantage. These changes do not amount to a paradigm shift, a la Paul Krugmanâs ideas. Yet crisisâridden countries that are keen to avoid punishing austerity packages can exploit this doctrinal shift by exploring the policy implications of the IMFâs own official fiscal doctrine and staff research. They can cut less spending, shelter the most disadvantaged, tax more at the top of income distribution and think twice before rushing into a fast austerity package. This much is clear in all of the Fundâs World Economic Outlooks and Global Fiscal Monitors published between 2009 and 2013 with regard to four themes: the main goals of fiscal policy, the basic options for countries with fiscal/without fiscal space, the pace of fiscal consolidation, and the composition of fiscal stimulus and consolidation
Purifying Nucleic Acids from Samples of Extremely Low Biomass
A new method is able to circumvent the bias to which one commercial DNA extraction method falls prey with regard to the lysing of certain types of microbial cells, resulting in a truncated spectrum of microbial diversity. By prefacing the protocol with glass-bead-beating agitation (mechanically lysing a much more encompassing array of cell types and spores), the resulting microbial diversity detection is greatly enhanced. In preliminary studies, a commercially available automated DNA extraction method is effective at delivering total DNA yield, but only the non-hardy members of the bacterial bisque were represented in clone libraries, suggesting that this method was ineffective at lysing the hardier cell types. To circumvent such a bias in cells, yet another extraction method was devised. In this technique, samples are first subjected to a stringent bead-beating step, and then are processed via standard protocols. Prior to being loaded into extraction vials, samples are placed in micro-centrifuge bead tubes containing 50 micro-L of commercially produced lysis solution. After inverting several times, tubes are agitated at maximum speed for two minutes. Following agitation, tubes are centrifuged at 10,000 x g for one minute. At this time, the aqueous volumes are removed from the bead tubes and are loaded into extraction vials to be further processed via extraction regime. The new method couples two independent methodologies in such as way as to yield the highest concentration of PCR-amplifiable DNA with consistent and reproducible results and with the most accurate and encompassing report of species richness
Matrix Completion With Variational Graph Autoencoders: Application in Hyperlocal Air Quality Inference
Inferring air quality from a limited number of observations is an essential
task for monitoring and controlling air pollution. Existing inference methods
typically use low spatial resolution data collected by fixed monitoring
stations and infer the concentration of air pollutants using additional types
of data, e.g., meteorological and traffic information. In this work, we focus
on street-level air quality inference by utilizing data collected by mobile
stations. We formulate air quality inference in this setting as a graph-based
matrix completion problem and propose a novel variational model based on graph
convolutional autoencoders. Our model captures effectively the spatio-temporal
correlation of the measurements and does not depend on the availability of
additional information apart from the street-network topology. Experiments on a
real air quality dataset, collected with mobile stations, shows that the
proposed model outperforms state-of-the-art approaches
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Identification of Bacteria and Determination of Biological Indicators
The ultimate goal of planetary protection research is to develop superior strategies for inactivating resistance bearing micro-organisms like Rummeli - bacillus stabekisii. By first identifying the particular physiologic pathway and/or structural component of the cell/spore that affords it such elevated tolerance, eradication regimes can then be designed to target these resistance-conferring moieties without jeopardizing the structural integrity of spacecraft hardware. Furthermore, hospitals and government agencies frequently use biological indicators to ensure the efficacy of a wide range of sterilization processes. The spores of Rummelibacillus stabekisii, which are far more resistant to many of such perturbations, could likely serve as a more significant biological indicator for potential survival than those being used currently
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