1,719 research outputs found

    Innovation in flood risk management: an 'Avenues of Innovation' analysis

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    Innovation in flood risk management (FRM) is a driver for change. Research, however, is sparse in this area, and innovation itself appears to be left largely to chance. This paper uses a ’systems of innovation’ approach, defining ’avenues’ of innovation, to explore factors that promote or inhibit innovation. The research is based on in-depth interviews with 10 leading figures in FRM in the United Kingdom, and describes the interactions and iterations involved. We conclude that in terms of practice the encouragement of champions should be enhanced, risk cultures require concerted attention to minimise risk aversion, learning should be facilitated, and innovation scaled up to maximise its effectiveness. We aim also to add to the literature on innovation systems, providing a case study of a complex field previously unexplored in this regard. Detailed innovation-encouraging processes here need to be better understood and FRM policies and practices adjusted accordingly

    Women and the Scottish Clerks' Association: from contempt to collegiality

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    First paragraph: This paper will trace the evolution of the attitudes expressed by the Scottish Clerks' Association (SCA) towards women in clerical work in the late nineteenth and early twentieth century. For women trying to establish careers in office work it was necessary to be accepted as colleagues by men in organisations like the SCA. But, as Sylvia Walby noted, explanations of the increasing presence of women in clerical work in the late nineteenth and early twentieth century have emphasised the role of employers as the main actors in the feminisation of clerical work, while the resistance (or acceptance) by male clerks has been given less attention. The evolution of the SCA's attitudes illustrates such resistance and then the growth of a kind of acceptance of women clerks in the early twentieth century; but this acceptance was within the context of male clerks' attempts to restructure their occupational group in order to preserve the better jobs for themselves

    Assessing Operational Accuracy of CNN-based Image Classifiers using an Oracle Surrogate

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    Context Assessing the accuracy in operation of a Machine Learning (ML) system for image classification on arbitrary (unlabeled) inputs is hard. This is due to the oracle problem, which impacts the ability of automatically judging the output of the classification, thus hindering the accuracy of the assessment when unlabeled previously unseen inputs are submitted to the system. Objective We propose the Image Classification Oracle Surrogate (ICOS), a technique to automatically evaluate the accuracy in operation of image classifiers based on Convolutional Neural Networks (CNNs). Method To establish whether the classification of an arbitrary image is correct or not, ICOS leverages three knowledge sources: operational input data, training data, and the ML algorithm. Knowledge is expressed through likely invariants - properties which should not be violated by correct classifications. ICOS infers and filters invariants to improve the correct detection of misclassifications, reducing the number of false positives. We evaluate ICOS experimentally on twelve CNNs – using the popular MNIST, CIFAR10, CIFAR100, and ImageNet datasets. We compare it to two alternative strategies, namely cross-referencing and self-checking. Results Experimental results show that ICOS exhibits performance comparable to the other strategies in terms of accuracy, showing higher stability over a variety of CNNs and datasets with different complexity and size. Conclusions ICOS likely invariants are shown to be effective in automatically detecting misclassifications by CNNs used in image classification tasks when the expected output is unknown; ICOS ultimately yields faithful assessments of their accuracy in operation. Knowledge about input data can also be manually incorporated into ICOS, to increase robustness against unexpected phenomena in operation, like label shift

    The X-ray Spectrum of the Rapid Burster using the Chandra HETGS

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    We present observations of the Rapid Burster (RB, also known as MXB 1730-335) using the Chandra High Energy Transmission Grating Spectrometer. The average interval between type II (accretion) bursts was about 40 s. There was one type I (thermonuclear flash) burst and about 20 "mini-bursts" which are probably type II bursts whose peak flux is 10-40% of the average peak flux of the other type II bursts. The time averaged spectra of the type II bursts are well fit by a blackbody with a temperature of kT = 1.6 keV, a radius of 8.9 km for a distance of 8.6 kpc, and an interstellar column density of 1.7e22 per sq. cm. No narrow emission or absorption lines were clearly detected. The 3 sigma upper limits to the equivalent widths of any features are < 10 eV in the 1.1-7.0 keV band and as small as 1.5 eV near 1.7 keV. We suggest that Comptonization destroys absorption features such as the resonance line of Fe XXVI.Comment: 10 pages, 4 figures, accepted for publication in AJ (with minor changes and enhanced discussion of the instrument configuration

    Deep Radio Imaging of Globular Clusters and the Cluster Pulsar Population

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    We have obtained deep multifrequency radio observations of seven globular clusters using the Very Large Array and the Australia Telescope Compact Array. Five of these, NGC 6440, NGC 6539, NGC 6544, NGC 6624 and Terzan 5 had previously been detected in a shallower survey for steep spectrum radio sources in globular clusters (Fruchter and Goss 1990). The sixth, the rich globular cluster, Liller 1, had heretofore been undetected in the radio, and the seventh, 47 Tucanae, was not included in our original survey. High resolution 6 and 20 cm images of three of the clusters, NGC 6440, NGC 6539, NGC 6624 reveal only point sources coincident with pulsars which have been discovered subsequent to our first imaging survey. 21 and 18 cm images reveal several point sources within a few core-radii of the center of 47 Tuc. Two of these are identified pulsars, and a third, which is both variable and has a steep spectrum, is also most likely a pulsar previously identified by a pulsed survey. However, the 6, 20 and 90 cm images of NGC 6544, Liller 1 and Terzan 5 display strong steep-spectrum emission which cannot be associated with known pulsars. The image of the rich cluster Terzan 5 displays numerous point sources within 30′′30'', or 4 core radii of the cluster center. The density of these objects rises rapidly toward the core, where an elongated region of emission is found. The brightest individual sources, as well as the extended emission, possess the steep spectra expected of pulsars. Furthermore, the flux distribution of the sources agrees well with the standard pulsar luminosity function. The total luminosity and number of objects observed suggest that Terzan 5 contains more pulsars than any other Galactic globular cluster.Comment: 33 pages, 6 Postscript figures; Accepted for publication in the Astrophysical Journal; abstract abridged. PDF version also available at http://nemesis.stsci.edu/~fruchter/fg99/fg99.pd

    Change-of-direction deficit vs. deceleration deficit: a comparison of limb dominance and inter-limb asymmetry between forwards and backs in elite male rugby union players

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    The aims of the present study were to: 1) determine whether limb dominance and inter-limb asymmetry were the same across both change of direction (COD) and deceleration (DEC) deficits and, 2) determine the association between the COD and DEC-deficits and other physical performance tests in elite male rugby union players. Twenty five players performed a series of bilateral jumps, linear and COD speed tests at the end of the pre-season period. COD and DEC-deficits were calculated for both left and right sides, and inter-limb asymmetry thereafter. Kappa coefficients revealed moderate levels of agreement in limb dominance between COD and DEC-deficits (Kappa = 0.41 on left; 0.48 on right). For the direction of asymmetry, perfect levels of agreement (Kappa = 1) were evident between 505 time and COD-deficit, but only moderate levels of agreement (Kappa = 0.41) between other asymmetry measures. Pearson’s r correlations showed moderate to large relationships between jumps and linear (r = -0.42 to -0.68) and COD speed (r = -0.41 to -0.58), but not with the COD-deficit (r = 0.15 to -0.31), DEC-deficit (r = 0.01 to -0.32) or asymmetry (r = 0.16 to -0.29). When analyzing by playing position, backs were significantly faster than forwards over 15-m (ES = -0.86) and across all jump tests (ES = 0.86-0.94), with the exception of the squat jump. This study is the first to provide a direct comparison of the COD and DEC-deficits and highlights that limb dominance and asymmetry cannot be guaranteed between tasks

    The discovery of hard X-ray emission in the persistent flux of the Rapid Burster

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    We report the first detection with INTEGRAL of persistent hard X-ray emission (20 to 100 keV) from the Rapid Burster (MXB 1730-335), and describe its full spectrum from 3 to 100 keV. The source was detected on February/March 2003 during one of its recurrent outbursts. The source was clearly detected with a high signal to noise ratio during the single pointings and is well distinguished from the neighboring source GX 354-0. The 3 - 100 keV X-ray spectrum of the persistent emission is well described by a two-component model consisting of a blackbody plus a power-law with photon index ~ 2.4. The estimated luminosity was ~ 8.5x10^{36} erg/s in the 3 - 20 keV energy band and \~ 1.3x10^{36} erg/s in the 20 - 100 keV energy range, for a distance of 8 kpc.Comment: 5 pages, 6 figures, 1 table. Accepted for publication in A&

    Impact of SARS-CoV-2 on dentistry: a review of literature.

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    OBJECTIVE: SARS-CoV-2 is a new Coronavirus identified as the cause of Corona- virus disease in 2019 (COVID-19). The epidemic spread in China and beyond its borders, involv- ing 114 countries with more than 5 million dead. On March 11, the WHO declared the spread of SARS-CoV-2 to be a pandemic and encouraged nations to adopt harsh restrictive measures. Therefore, patients more and more often turn to dental offices only for emergencies. Healthcare professionals, including dentists, are at high in- fectious risk. In fact, the closeness to the oral cavity and nasopharynx and the use of drills or ultrasonic devices that cause aerosol release, make dental professions at high risk of bacterial and viral infections. The way patients are treat- ed has changed. In fact, it should be mandato- ry to carry out a pre-treatment telephone triage and the use of mouthwashes to reduce bacterial load. In the current pandemic, it is necessary to adopt specific safety protocols that can protect dental operators as well as limit the spread of the virus. The purpose of this review is to pres- ent an overview on ways to reduce the risk of SARS-CoV-2 contagion in dentistry by focusing on the immediate situation as well as by look- ing towards the future. MATERIALS AND METHODS: To reach the review purpose, we selected a series of studies using keywords “COVID-19” OR “SARS-CoV-2” in association with “dentistry” AND “safety proto- cols” AND “healthcare procedures” AND “individ- ual protection dispositive” AND “air transmission” AND “droplet”. We selected papers exclusively in English language, up to 1st January 2022. RESULTS: During future phases of the pan- demic, everywhere in the World, it is necessary to impose all dentistry team both a serological screening and the vaccination, as already estab- lished for all health staff in Italy. CONCLUSIONS: For own safety, it is an import- ant for the whole dentistry category constantly update the devices and the protocols adopted, as well as monitoring the real infectious threats, which may occur
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