141 research outputs found
Experimenting with experiments : An introduction
From the introduction:
This special issue is dedicated to the exploration of experiments and experimentation. It follows a PhD. course entitled âExploring and performing experimentsâ that we organized at Department of Digital Design and Information Studies in spring 2019. The course was attended by 12 PhD fellows, and during the course we and the participants decided to produce a special issue based on the participantsâ PhD research projects. The literature for the course included a variety of texts and research articles focusing on experiments mainly from the field of Science and Technology Studies (STS). The readings included the work of Ian Hacking, Andy Pickering, Bruno Latour, Steven Shapin and Simon Schaffer, Isabelle Stengers, Shirley Strum and Brian Eno among others. In the call for papers for this issue authors were asked to draw on the literature in the field of STS in order to explore the role of experiments and experimentation in their own projects, and to consider their articles as vehicles for bringing insights from STS to their own fields. The spirit of this special issue is thus one of âSTS pollinationâ by bringing STS to other fields, rather than necessarily being contributions to STS itself. Hopefully it will generate novel insights and contributions and perhaps cross-pollinatio
Three-Dimensional Double-Ridge Internal Tide Resonance in Luzon Strait
The three-dimensional (3D) double-ridge internal tide interference in the Luzon Strait in the South China Sea is examined by comparing 3D and two-dimensional (2D) realistic simulations. Both the 3D simulations and observations indicate the presence of 3D first-mode (semi)diurnal standing waves in the 3.6-km-deep trench in the strait. As in an earlier 2D study, barotropic-to-baroclinic energy conversion, flux divergence, and dissipation are greatly enhanced when semidiurnal tides dominate relative to periods dominated by diurnal tides. The resonance in the 3D simulation is several times stronger than in the 2D simulations for the central strait. Idealized experiments indicate that, in addition to ridge height, the resonance is only a function of separation distance and not of the along-ridge length; that is, the enhanced resonance in 3D is not caused by 3D standing waves or basin modes. Instead, the difference in resonance between the 2D and 3D simulations is attributed to the topographic blocking of the barotropic flow by the 3D ridges, affecting wave generation, and a more constructive phasing between the remotely generated internal waves, arriving under oblique angles, and the barotropic tide. Most of the resonance occurs for the first mode. The contribution of the higher modes is reduced because of 3D radiation, multiple generation sites, scattering, and a rapid decay in amplitude away from the ridge
Recommended from our members
Structure and Variability of Internal Tides in Luzon Strait
The Luzon Strait is the generation region for strong internal tides that radiate westward into the South China Sea and eastward into the western Pacific. Intrusions of the Kuroshio and strong mesoscale variability in the Luzon Strait can influence their generation and propagation. Here, the authors use eight moorings and two numerical models to investigate these relationships by quantifying the coherence of the diurnal and semidiurnal internal tides in the Luzon Strait. This study finds that the level of coherence of internal tide generation, energy, and energy flux is quite variable, depending on the specific location within the Luzon Strait. Large-scale spatial patterns in internal tide pressure and velocity exist across the region, shaped by the bathymetry, mean flow, and stratification. Internal tide coherence is lower (80%), and simple calculations suggest that remote sources of internal tides could account for these small decreases in coherence. To the west of the Luzon Strait (away from the primary generation regions), the model suggests that diurnal internal tide energy is more coherent than semidiurnalKeywords: Circulation, Dynamics, oceanic, Internal waves, Atm, Waves, Oceanic variability, Phenomena, Tides, Ocean Structure, VariabilityKeywords: Circulation, Dynamics, oceanic, Internal waves, Atm, Waves, Oceanic variability, Phenomena, Tides, Ocean Structure, Variabilit
Recommended from our members
Three-Dimensional Double-Ridge Internal Tide Resonance in Luzon Strait
The three-dimensional (3D) double-ridge internal tide interference in the Luzon Strait in the South China
Sea is examined by comparing 3D and two-dimensional (2D) realistic simulations. Both the 3D simulations
and observations indicate the presence of 3D first-mode (semi)diurnal standing waves in the 3.6-km-deep
trench in the strait. As in an earlier 2D study, barotropic-to-baroclinic energy conversion, flux divergence, and
dissipation are greatly enhanced when semidiurnal tides dominate relative to periods dominated by diurnal
tides. The resonance in the 3D simulation is several times stronger than in the 2D simulations for the central
strait. Idealized experiments indicate that, in addition to ridge height, the resonance is only a function of
separation distance and not of the along-ridge length; that is, the enhanced resonance in 3D is not caused by
3D standing waves or basin modes. Instead, the difference in resonance between the 2D and 3D simulations is
attributed to the topographic blocking of the barotropic flow by the 3D ridges, affecting wave generation, and
a more constructive phasing between the remotely generated internal waves, arriving under oblique angles,
and the barotropic tide. Most of the resonance occurs for the first mode. The contribution of the higher modes
is reduced because of 3D radiation, multiple generation sites, scattering, and a rapid decay in amplitude away
from the ridge.Keywords: Regional models, Numerical analysis/modeling, Models and modeling, Resonance, Circulation/Dynamics, Tides, Internal waves, Ocean models, Physical Meteorology and Climatology, Atm/Ocean Structure/Phenomen
The hospital microbiome project: meeting report for the UK science and innovation network UK-USA workshop âbeating the superbugs: hospital microbiome studies for tackling antimicrobial resistanceâ, October 14th 2013
The UK Science and Innovation Network UK-USA workshop âBeating the Superbugs: Hospital Microbiome Studies for tackling Antimicrobial Resistanceâ was held on October 14th 2013 at the UK Department of Health, London. The workshop was designed to promote US-UK collaboration on hospital microbiome studies to add a new facet to our collective understanding of antimicrobial resistance. The assembled researchers debated the importance of the hospital microbial community in transmission of disease and as a reservoir for antimicrobial resistance genes, and discussed methodologies, hypotheses, and priorities. A number of complementary approaches were explored, although the importance of the built environment microbiome in disease transmission was not universally accepted. Current whole genome epidemiological methods are being pioneered in the UK and the benefits of moving to community analysis are not necessarily obvious to the pioneers; however, rapid progress in other areas of microbiology suggest to some researchers that hospital microbiome studies will be exceptionally fruitful even in the short term. Collaborative studies will recombine different strengths to tackle the international problems of antimicrobial resistance and hospital and healthcare associated infections
Data-based analysis of speech and gesture: the Bielefeld Speech and Gesture Alignment corpus (SaGA) and its applications
LĂŒcking A, Bergmann K, Hahn F, Kopp S, Rieser H. Data-based analysis of speech and gesture: the Bielefeld Speech and Gesture Alignment corpus (SaGA) and its applications. Journal on Multimodal User Interfaces. 2013;7(1-2):5-18.Communicating face-to-face, interlocutors frequently produce multimodal meaning packages consisting of speech and accompanying gestures. We discuss a systematically annotated speech and gesture corpus consisting of 25 route-and-landmark-description dialogues, the Bielefeld Speech and Gesture Alignment corpus (SaGA), collected in experimental face-to-face settings. We first describe the primary and secondary data of the corpus and its reliability assessment. Then we go into some of the projects carried out using SaGA demonstrating the wide range of its usability: on the empirical side, there is work on gesture typology, individual and contextual parameters influencing gesture production and gesturesâ functions for dialogue structure. Speech-gesture interfaces have been established extending unification-based grammars. In addition, the development of a computational model of speech-gesture alignment and its implementation constitutes a research line we focus on
Recommended from our members
Energy Flux and Dissipation in Luzon Strait: Two Tales of Two Ridges
Internal tide generation, propagation, and dissipation are investigated in Luzon Strait, a system of two quasi-parallel ridges situated between Taiwan and the Philippines. Two profiling moorings deployed for about 20 days and a set of nineteen 36-h lowered ADCPâCTD time series stations allowed separate measurement of diurnal and semidiurnal internal tide signals. Measurements were concentrated on a northern line, where the ridge spacing was approximately equal to the mode-1 wavelength for semidiurnal motions, and a southern line, where the spacing was approximately two-thirds that. The authors contrast the two sites to emphasize the potential importance of resonance between generation sites. Throughout Luzon Strait, baroclinic energy, energy fluxes, and turbulent dissipation were some of the strongest ever measured. Peak-to-peak baroclinic velocity and vertical displacements often exceeded 2 m sâ»Âč and 300 m, respectively. Energy fluxes exceeding 60 kW mâ»Âč were measured at spring tide at the western end of the southern line. On the northern line, where the western ridge generates appreciable eastward-moving signals, net energy flux between the ridges was much smaller, exhibiting a nearly standing wave pattern. Overturns tens to hundreds of meters high were observed at almost all stations. Associated dissipation was elevated in the bottom 500â1000 m but was strongest by far atop the western ridge on the northern line, where >500-m overturns resulted in dissipation exceeding 2 Ă 10â»â¶ W kgâ»Âč (implying diapycnal diffusivity K[subscript]Ï > 0.2 mÂČ sâ»Âč). Integrated dissipation at this location is comparable to conversion and flux divergence terms in the energy budget. The authors speculate that resonance between the two ridges may partly explain the energetic motions and heightened dissipation.Keywords: Internal waves, MixingKeywords: Internal waves, Mixin
Recommended from our members
Energy Flux and Dissipation in Luzon Strait: Two Tales of Two Ridges
Internal tide generation, propagation, and dissipation are investigated in Luzon Strait, a system of two quasi-parallel ridges situated between Taiwan and the Philippines. Two profiling moorings deployed for about 20 days and a set of nineteen 36-h lowered ADCP-CTD time series stations allowed separate measurement of diurnal and semidiurnal internal tide signals. Measurements were concentrated on a northern line, where the ridge spacing was approximately equal to the mode-1 wavelength for semidiurnal motions, and a southern line, where the spacing was approximately two-thirds that. The authors contrast the two sites to emphasize the potential importance of resonance between generation sites. Throughout Luzon Strait, baroclinic energy, energy fluxes, and turbulent dissipation were some of the strongest ever measured. Peak-to-peak baroclinic velocity and vertical displacements often exceeded 2 m sâ»Âč and 300 m, respectively. Energy fluxes exceeding 60 kW mâ»Âč were measured at spring tide at the western end of the southern line. On the northern line, where the western ridge generates appreciable eastward-moving signals, net energy flux between the ridges was much smaller, exhibiting a nearly standing wave pattern. Overturns tens to hundreds of meters high were observed at almost all stations. Associated dissipation was elevated in the bottom 500-1000 m but was strongest by far atop the western ridge on the northern line, where >500-m overturns resulted in dissipation exceeding 2 x 10â»â¶ W kgâ»Âč (implying diapycnal diffusivity K[subscript p] > 0.2 mÂČ sâ»Âč). Integrated dissipation at this location is comparable to conversion and flux divergence terms in the energy budget. The authors speculate that resonance between the two ridges may partly explain the energetic motions and heightened dissipation.Keywords: Propagation, South China sea, Generation, Hawaiian ridge, Turbulence, Topography, Model, Internal tide, Ocea
- âŠ