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Model independent expansion history from supernovae: Cosmology versus systematics
We examine the Pantheon supernovae distance data compilation in a model independent analysis to test the validity of cosmic history reconstructions beyond the concordance CDM cosmology. Strong deviations are allowed by the data at z 1 in the reconstructed Hubble parameter, Om diagnostic, and dark energy equation of state. We explore three interpretations: 1) possibility of the true cosmology being far from CDM, 2) supernovae property evolution, and 3) survey selection effects. The strong (and theoretically problematic) deviations at z 1 vanish and good consistency with CDM is found with a simple Malmquist-like linear correction. The adjusted data is robust against the model independent iterative smoothing reconstruction. However, we caution that while by eye the original deviation from CDM is striking, Ï2 tests do not show the extra linear correction parameter is statistically significant, and a model-independent Gaussian Process regression does not find significant evidence for the need for correction at high-redshifts
Rule-based Procedural Generation of Item in Role-playing Game
This paper demonstrates the significance of rule-based procedural generation of item in role-playing game. The main aims of this project are to: implement rule-based randomized algorithm and totally randomized algorithm in generating item procedurally in Role-Playing Game (RPG), and compare the advantage of rule-based randomized algorithm against totally randomized algorithm in item drop mechanism. Experimental results demonstrate success with all aims: rule-based randomized algorithm is proven to be a better game changing factor in procedural generation of item as it can control the prolific generation of strong items in the early stage of the game. This helps to balance the game and prevents any snow-balling effect as the game progresses
Improving the Representation of Cross-Boundary Transport of Anthropogenic Pollution in East Asia Using Radon-222.
We report on 10 years of hourly atmospheric radon, CO, and SO2 observations at Gosan Station, Korea. An improved radon detector was installed during this period and performance of the detectors is compared. A technique is developed whereby the distribution of radon concentrations from a fetch region can be used to select air masses that have consistently been in direct contact with land-based emissions, and have been least diluted en route to the measurement site. Hourly radon concentrations are used to demonstrate and characterise contamination of remote-fetch pollution observations by local emissions at this key WMO GAW site, and a seasonally-varying 5-hour diurnal sampling window is proposed for
days on which diurnal cycles are evident to minimise these effects. The seasonal variability in mixing depth and
âbackgroundâ pollutant concentrations are characterised. Based on a subset of observations most representative of the
important regional fetch areas for this site, and least affected by local emissions, seasonal estimates of CO and SO2 in air
masses originating from South China, North China, Korea and Japan are compared across the decade of observations. 2016, © Taiwan Association for Aerosol Researc
The anomalous U(1) global symmetry and flavors from an SU(5) x SU(5) GUT in orbifold compactification
In string compactifications, frequently there appears the anomalous U(1)
gauge symmetry which belonged to E8E8 of the heterotic string. This
anomalous U(1) gauge boson obtains mass at the compactification scale, just
below GeV, by absorbing one pseudoscalar (corresponding to the
model-independent axion) from the second rank anti-symmetric tensor field
.
Below the compactification scale, there results a global symmetry U(1) whose charge is the original gauge U(1) charge. This is
the most natural global symmetry, realizing the "invisible" axion. This global
symmetry U(1) is suitable for a flavor symmetry. In the simplest
compactification model with the flipped SU(5) grand unification, we calculate
all the low energy parameters in terms of the vacuum expectation values of the
standard model singlets.Comment: 18 pages, 4 figur
Low electronic conductivity of Li7La3Zr2 O12 solid electrolytes from first principles
Lithium-rich garnets such as Li7La3Zr2O12 (LLZO) are promising solid electrolytes with potential application in all-solid-state batteries that use lithium-metal anodes. The practical use of garnet electrolytes is limited by pervasive lithium-dendrite growth, which leads to short-circuiting and cell failure. One proposed mechanism of lithium-dendrite growth is the direct reduction of lithium ions to lithium metal within the electrolyte, and lithium garnets have been suggested to be particularly susceptible to this dendrite-growth mechanism due to high electronic conductivities relative to other solid electrolytes. The electronic conductivities of LLZO and other lithium-garnet solid electrolytes, however, are not yet well characterized. Here, we present a general scheme for calculating the intrinsic electronic conductivity of a nominally insulating material under variable synthesis conditions from first principles, and apply this to the prototypical lithium-garnet LLZO. Our model predicts that under typical battery operating conditions, electron and hole mobilities are low (<1cm2V-1s-1), and bulk electron and hole carrier concentrations are negligible, irrespective of initial synthesis conditions or dopant levels. These results suggest that the bulk electronic conductivity of LLZO is not sufficiently high to cause bulk lithium-dendrite growth during cell operation, and that any non-negligible electronic conductivity in lithium garnet samples is likely due to extended defects or surface contributions
Liquid-phase synthesis of 2âČ-methyl-RNA on a homostar support through organic-solvent nanofiltration
Due to the discovery of RNAi, oligonucleotides (oligos) have re-emerged as a major pharmaceutical target that may soon be required in ton quantities. However, it is questionable whether solid-phase oligo synthesis (SPOS) methods can provide a scalable synthesis. Liquid-phase oligo synthesis (LPOS) is intrinsically scalable and amenable to standard industrial batch synthesis techniques. However, most reported LPOS strategies rely upon at least one precipitation per chain extension cycle to separate the growing oligonucleotide from reaction debris. Precipitation can be difficult to develop and control on an industrial scale and, because many precipitations would be required to prepare a therapeutic oligonucleotide, we contend that this approach is not viable for large-scale industrial preparation. We are developing an LPOS synthetic strategy for 2âČ-methyl RNA phosphorothioate that is more amenable to standard batch production techniques, using organic solvent nanofiltration (OSN) as the critical scalable separation technology. We report the first LPOS-OSN preparation of a 2âČ-Me RNA phosphorothioate 9-mer, using commercial phosphoramidite monomers, and monitoring all reactions by HPLC, (31)P NMR spectroscopy and MS
Empfehlungen zur RDF-ReprÀsentation bibliografischer Daten
Die Gruppe Titeldaten wurde im Januar 2012 gegrĂŒndet, seit April 2012 agiert sie als
Untergruppe des Kompetenzzentrums Interoperable Metadaten (DINI-AG KIM). KIM ist eine
Arbeitsgruppe der Deutschen Initiative fĂŒr Netzwerkinformation e. V. (DINI e.V.).
Vertreten sind alle deutschen BibliotheksverbĂŒnde, die Deutsche Nationalbibliothek, die
Ăsterreichische Bibliothekenverbund und Service GmbH, die Schweizerische
Nationalbibliothek sowie einige weitere interessierte und engagierte Kolleginnen und
Kollegen mit entsprechender Expertise. Die Moderation und Koordination liegt bei der
Deutschen Nationalbibliothek.
Die Gruppe Titeldaten dient als Forum fĂŒr den fachlichen Austausch ĂŒber die ReprĂ€sentation
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Transformation vorhandener Titeldaten nach RDF.
Ergebnis dieser Diskussionen sind die "Empfehlungen zur RDF-ReprÀsentation
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dokumentieren Lösungen und zeigen mögliche Alternativen auf. Sie sollen zum einen
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Low energy intensity production of fuel-grade bio-butanol enabled by membrane-based extraction
Widespread use of biofuels is inhibited by the significant energy burden of recovering fuel products from aqueous fermentation systems. Here, we describe a membrane-based extraction (perstraction) system for the recovery of fuel-grade biobutanol from fermentation broths which can extract n-butanol with high purity (>99.5%) while using less than 25% of the energy of current technology options. This is achieved by combining a spray-coated thin-film composite membrane with 2-ethyl-1-hexanol as an extractant. The membrane successfully protects the micro-organisms from the extractant, which, although ideal in other respects, is a metabolic inhibitor. In contrast to water, the extractant does not form a heterogeneous azeotrope with n-butanol, and the overall energy consumption of for n-butanol production is 3.9 MJ kgâ1, substantially less than other recovery processes (17.0â29.4 MJ kgâ1). By (a) extracting n-butanol from the fermentation broth without a phase change, (b) breaking the heterogeneous azeotrope relationship (less energy consumption for distillation), and (c) utilizing a small volume ratio of extractantâ:âfermentation broth (1â:â100, v/v), the need for high energy intensity processes such as pervaporation, gas stripping or liquidâliquid extraction is avoided. The application of this perstraction system to continuous production of a range of higher alcohols is explored and shown to be highly favourable
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