Capability in the digital: institutional media management and its dis/contents

This paper explores how social media spaces are occupied, utilized and negotiated by the British Military in relation to the Ministry of Defence’s concerns and conceptualizations of risk. It draws on data from the DUN Project to investigate the content and form of social media about defence through the lens of ‘capability’, a term that captures and describes the meaning behind multiple representations of the military institution. But ‘capability’ is also a term that we hijack and extend here, not only in relation to the dominant presence of ‘capability’ as a representational trope and the extent to which it is revealing of a particular management of social media spaces, but also in relation to what our research reveals for the wider digital media landscape and ‘capable’ digital methods. What emerges from our analysis is the existence of powerful, successful and critically long-standing media and reputation management strategies occurring within the techno-economic online structures where the exercising of ‘control’ over the individual – as opposed to the technology – is highly effective. These findings raise critical questions regarding the extent to which ‘control’ and management of social media – both within and beyond the defence sector – may be determined as much by cultural, social, institutional and political influence and infrastructure as the technological economies. At a key moment in social media analysis, then, when attention is turning to the affordances, criticisms and possibilities of data, our research is a pertinent reminder that we should not forget the active management of content that is being similarly, if not equally, effective

EUV Sunspot Plumes Observed with SOHO

Bright EUV sunspot plumes have been observed in five out of nine sunspot regions with the Coronal Diagnostic Spectrometer -- CDS on SOHO. In the other four regions the brightest line emissions may appear inside the sunspot but are mainly concentrated in small regions outside the sunspot areas. These results are in contrast to those obtained during the Solar Maximum Mission, but are compatible with the Skylab mission results. The present observations show that sunspot plumes are formed in the upper part of the transition region, occur both in magnetic unipolar-- and bipolar regions, and may extend from the umbra into the penumbra.Comment: 8 pages, 3 figures, to be published in ApJ Letter

A Frequency Bin Analysis of Distinctive Ranges Between Human and Deepfake Generated Voices

Deepfake technology has advanced rapidly in recent years. The widespread availability of deepfake audio technology has raised concerns about its potential misuse for malicious purposes, and a need for more robust countermeasure systems is becoming ever more important. Here we analyse the differences between human and deepfake audio and introduce a novel audio pre-processing approach. Our analysis aims to show the specific locations in the frequency spectrum where these artefacts and distinctions between human and deepfake audio can be found. Our approach emphasises specific frequency ranges that we show are transferable across synthetic speech datasets. In doing so, we explore the use of a bespoke filter bank derived from our analysis of the WaveFake dataset to exploit commonalities across algorithms. Our filter bank was constructed based on a frequency bin analysis of the WaveFake dataset, we apply this filter bank to adjust gain/attenuation to improve the effective signal-to-noise ratio, doing so we reduce the similarities while accentuating differences. We then take a baseline performing model and experiment with improving the performance using these frequency ranges to show where these artefacts lie and if this knowledge is transferable across mel-spectrum algorithms. We show that there exist exploitable commonalities between deepfake voice generation methods that generate audio in the mel-spectrum and that artefacts are left behind in similar frequency regions. Our approach is evaluated on the ASVSpoof 2019 Logical Access dataset of which the test set contains unseen generative methods to test the efficacy of our filter bank approach and transferability. Our experiments show that there is enhanced classification performance to be gained from utilizing these transferable frequency bands where there are more artefacts and distinctions. Our highest-performing model provided a 14.75% improvement in Equal Error Rate against our baseline model

On the correlation between Ca and Halpha solar emission and consequences for stellar activity observations

The correlation between Ca and Halpha chromospheric emission, known to be positive in the solar case, has been found to vary between -1 and 1 for other stars. Our objective is to understand the factors influencing this correlation in the solar case, and then to extrapolate our interpretation to other stars. We characterize the correlation between both types of emission in the solar case for different time scales. Then we determine the filling factors due to plages and filaments, and reconstruct the Ca and Halpha emission to test different physical conditions in terms of plage and filament contrasts. We have been able to precisely determine the correlation in the solar case as a function of the cycle phase. We interpret the results as reflecting the balance between the emission in plages and the absorption in filaments. We found that correlations close to zero or slightly negative can be obtained when considering the same spatio-temporal distribution of plages and filaments than on the sun but with greater contrast. However, with that assumption, correlations close to -1 cannot be obtained for example. Stars with a very low Halpha contrast in plages and filaments well correlated with plages could produce a correlation close to -1. This study opens new ways to study stellar activity, and provides a new diagnosis that will ultimately help to understand the magnetic configuration of stars other than the sun.Comment: 10 pages, 13 figures, accepted in Astronomy and Astrophysic

Properties of sunspots in cycle 23: I. Dependence of brightness on sunspot size and cycle phase

In this paper we investigate the dependence of umbral core brightness, as well as the mean umbral and penumbral brightness on the phase of the solar cycle and on the size of the sunspot. Albregtsen & Maltby (1978) reported an increase in umbral core brightness from the early to the late phase of solar cycle from the analysis of 13 sunspots which cover solar cycles 20 and 21. Here we revisit this topic by analysing continuum images of more than 160 sunspots observed by the MDI instrument on board the SOHO spacecraft for the period between 1998 March to 2004 March, i.e. a sizable part of solar cycle 23. The advantage of this data set is its homogeneity, with no seeing fluctuations. A careful stray light correction, which is validated using the Mercury transit of 7th May, 2003, is carried out before the umbral and penumbral intensities are determined. The influence of the Zeeman splitting of the nearby NiI spectral line on the measured 'continuum' intensity is also taken into account. We did not observe any significant variation in umbral core, mean umbral and mean penumbral intensities with solar cycle, which is in contrast to earlier findings for the umbral core intensity. We do find a strong and clear dependence of the umbral brightness on sunspot size, however. The penumbral brightness also displays a weak dependence. The brightness-radius relationship has numerous implications, some of which, such as those for the energy transport in umbrae, are pointed out.Comment: 16 pages, 21 postscript figures, accepted for publication in A&

Short Utterance Dialogue Act Classification Using a Transformer Ensemble

An influx of digital assistant adoption and reliance is demonstrating the significance of reliable and robust dialogue act classification techniques. In the literature, there is an over-representation of purely lexical-based dialogue act classification methods. A weakness of this approach is the lack of context when classifying short utterances. We improve upon a purely lexical approach by incorporating a state-of-the-art acoustic model in a lexical-acoustic transformer ensemble, with improved results, when classifying dialogue acts in the MRDA corpus. Additionally, we further investigate the performance on an utterance word-count basis, showing classification accuracy increases with utterance word count. Furthermore, the performance of the lexical model increases with utterance word length and the acoustic model performance decreases with utterance word count, showing the models complement each other for different utterance lengths

A Novel Method of Determining Portal Systemic Shunting using Biodegradable 99TCm Labelled Albumin Microspheres

Portal systemic shunting (PSS) and portal pressure were measured in control rats and in animals with portal hypertension induced by partial portal vein ligation (PPVL). The portal pressure in rats with partial portal vein ligation (13.4 ± 0.5 mm.Hg.) was significantly higher (p < 0.005) than in the control group (9.6 ± 0.6 mm.Hg.). Portal systemic shunting measured by consecutive injections of radiolabelled methylene diphosphonate (MDP), a non-diffusable marker and albumin microspheres directly into the splenic pulp was significantly increased (P < 0.005) in the portal hypertensive animals (30.8 ± 2.5%) compared to sham operated rats (2.6 ± 1.5%). Similarly, in portal hypertensive rats portal systemic shunting measured by intrasplenic injections of radiolabelled cobalt microspheres (37.1 ± 3.9%) was significantly greater (p < 0.005) than in control animals. There was a good correlation and agreement (r = 00.97) between the two methods of measuring portal systemic shunting. However because the 99Tcm-albumin microspheres are biodegradable the method allows portal systemic shunting to be measured in man. Furthermore since the computer adjusts the baseline to zero after each determination of portal systemic shunting the methodology allows repeated measurements to be made

Censorship and the configuration of cinematic classicism

Practically from its origins, and especially once it had been consolidated as a spectacle for mass consumption, American cinema had to deal with censorship by different authorities at local, state and federal levels. The industry responded to the problems arising from such censorship by introducing self-regulation, expressed in the Motion Picture Production Code, popularly known as the Hays Code. In addition to their influence on the subjects chosen and how these were treated, these mechanisms of censorship and self-regulation had a highly significant influence on the filmic form. What role did censorship play in the transition from the cinema of attractions to a more narrative model? Was it a determining factor in the establishment of the Institutional Mode of Representation? How did the Production Code interact with other systems and formulas associated with classical cinema, such as the star system or the different film genres? How did the progressive relaxation and subsequent abandonment of the Code affect the mise-en-scène of films? How did classical cinema handle problematic elements related to filmic form resulting from the restrictions of the Code? In this section, six internationally renowned scholars address these questions and offer their views on the subject