86,696 research outputs found
Bass Culture film
No full textThe film ‘Bass Culture’, uniquely identified the musicians and industry professionals required to voice the creativity, across five decades of new musical genres. Driven by the perspective of youth, the film starts in the present and journeys back to the late 1950. Important to this film is the unbroken inter generational explanation, of the birth of, the most significant black British music genres since the 70s. All content was cross-checked with chart and sales data, industry experts and audience accounts
Estimation of River Width with Fully-Focused SAR Altimetry Data
No full textRiver width is an important indication for water storage, with the development of remote sensing techniques, estimating river width in a large area becomes possible. In this report, fully-focused SAR altimetry data with an advantage of high spatial resolution is applied to compute river width for the first time. Methodology developed based on morphologic characters of rivers and data features is validated in two different areas, the Netherlands and Vietnam, with good statistical results
Fully-focused delay-doppler processing algorithms for radar altimetry systems
No full textEvaluation of ice-height change in Antartica, forecasting river discharges or estimating water surface elevation in coastal waters are some of many applications of Altimetry science. The main objective of a satellite Radar Altimeter is to measure the height of reflecting objects on earth. Those reflections are obtained from the echoes of electromagnetic waves, which are continuously sent by the altimeter instrument. The conventional satellite altimeter uses the echo delays to estimate the height. One of the main features to improve in radar altimetry systems is the along-track resolution (i.e. the capacity to distinguish between two point-targets). Along-track resolution improvements can be achieved when using processing algorithms that coherently sum groups of received electromagnetic pulses, which have been reflected by the same target. Nowadays, operational altimeters achieve along-track resolutions over 200 meters thanks to Unfocused Delay-Doppler algorithms. However, Fully-Focused (FF) algorithms can improve the along-track resolution to the order of sub-meter. Two main approaches of Fully-Focused methods have been presented: Fully-Focused in Time Domain and Fully-Focused in Frequency Domain. Although both of them achieve the same along-track resolution, FF in Frequency has demonstrated to be considerably faster than FF in Time. In this thesis, we introduce the theory of both FF methods, and present the results and applications of Fully-Focused in Time Domain algorithm
Fully-focused delay-doppler processing algorithms for radar altimetry systems
No full textEvaluation of ice-height change in Antartica, forecasting river discharges or estimating water surface elevation in coastal waters are some of many applications of Altimetry science. The main objective of a satellite Radar Altimeter is to measure the height of reflecting objects on earth. Those reflections are obtained from the echoes of electromagnetic waves, which are continuously sent by the altimeter instrument. The conventional satellite altimeter uses the echo delays to estimate the height. One of the main features to improve in radar altimetry systems is the along-track resolution (i.e. the capacity to distinguish between two point-targets). Along-track resolution improvements can be achieved when using processing algorithms that coherently sum groups of received electromagnetic pulses, which have been reflected by the same target. Nowadays, operational altimeters achieve along-track resolutions over 200 meters thanks to Unfocused Delay-Doppler algorithms. However, Fully-Focused (FF) algorithms can improve the along-track resolution to the order of sub-meter. Two main approaches of Fully-Focused methods have been presented: Fully-Focused in Time Domain and Fully-Focused in Frequency Domain. Although both of them achieve the same along-track resolution, FF in Frequency has demonstrated to be considerably faster than FF in Time. In this thesis, we introduce the theory of both FF methods, and present the results and applications of Fully-Focused in Time Domain algorithm
Validity assessment of SAMOSA retracking for fully-focused SAR altimeter waveforms
No full textWe demonstrate in this work how we can take advantage of known unfocused SAR (UF-SAR) retracking methods (e.g. the physical SAMOSA model) for retracking of fully-focused SAR (FF-SAR) waveforms. Our insights are an important step towards consistent observations of sea surface height, significant wave height and backscatter coefficient (wind speed) with both UF-SAR and FF-SAR. This is of particular interest for SAR altimetry in the coastal zone, since coastal clutter may be filtered out more efficiently in the high-resolution FF-SAR waveform data, which has the potential to improve data quality. We implemented a multi-mission FF-SAR altimetry processor for Sentinel-3 (S3) and Sentinel-6 Michael Freilich (S6), using a back-projection algorithm, and analysed ocean waveform statistics compared to multilooked UF-SAR. We find for Sentinel-3 that the averaged power waveforms of UF-SAR and FF-SAR over ocean are virtually identical, while for Sentinel-6 the FF-SAR power waveforms better resemble the UF-SAR zero-Doppler beam. We can explain and model the similarities and differences in the data via theoretical considerations of the waveform integrals. These findings suggest to use the existing UF-SAR SAMOSA model for retracking S3 FF-SAR waveforms but the SAMOSA zero-Doppler beam model for S6 FF-SAR waveforms, instead. Testing the outlined approach over short track segments, we obtain range biases between UF-SAR and FF-SAR lower than 2 mm and significant wave height biases lower than 5 cm.</p
The second-order effect of Earth’s rotation on Cryosat-2 fully focused SAR processing
No full textWe investigated the sensitivity of fully focused SAR (FF-SAR) processing of Cryosat-2 altimeter data to Earth rotation. Earth’s rotation causes scatterers at varying cross-track locations to have a different relative velocity with respect to the satellite. This second-order effect of Earth rotation on the phase is currently not corrected for in FF-SAR processing of altimetry data. The difference is largest near the poles, where the satellite flies parallel to the equator. Not correcting for the second-order effect yields a parabolic shape in the counter-rotated phase, which increases with the cross-track distance. Its effect is, however, limited by the time-in-view of the scatterer, which is shorter at the edge of the altimeter footprint, and therefore destructive interference will not occur when using Cryosat-2 data. For Cryosat-2, the only expected effect is a reduction in power and along-track resolution in the waveform tail and in the grating lobes. If the FF-SAR processor focuses on one point, and there is a bright scatterer at another, then there is a residual parabolic phase, whose sign and shape depend on the cross-track distance and whether the signal is left or right of the chosen focal point. In theory, if the viewed scene only has few bright coherent scatterers, then it might be possible to determine the cross-track position of each. In practice, however, natural targets are rarely coherent over the integration time.Mathematical Geodesy and PositioningAstrodynamics & Space MissionsPhysical and Space GeodesyAtmospheric Remote Sensin
A Fully-Focused SAR Omega-K Closed-Form Algorithm for the Sentinel-6 Radar Altimeter: Methodology and Applications
No full textThe 2-D frequency-based omega-K method is known to be a suitable algorithm for fully focused SAR (FF-SAR) radar altimeter processors, as its computational efficiency is much higher than equivalent time-based alternatives without much performance degradation. In this article, we provide a closed-form description of a 2-D frequency-domain omega-K algorithm specific for instruments such as Poseidon-4 onboard Sentinel-6. The processor is validated with real data from point targets and over the open ocean. Applications such as ocean swell retrieval and lead detection are demonstrated, showing the potentiality of the processor for future operational global-scale products.Mathematical Geodesy and Positionin
Getting in the path of the robot: Pedestrians acceptance of crossing roads near fully automated vehicles
No full textAdoption of Automated Vehicles (AVs) within transport networks relies on the technology acceptance of not only AV users, but also other road users such as pedestrians. However, previous research has mostly focused on user acceptance of AVs and the receptivity of pedestrians towards AVs has been largely unexplored. This study aims to fill this gap by applying the Theory of Planned Behaviour (TPB), the Technology Acceptance Model (TAM), and the Unified Theory of Acceptance and Use of Technology (UTAUT) to investigate pedestrians’ intentions to cross a road in front of a fully AV. To achieve this goal, a 20-minute online questionnaire was administered in Australia and data were collected from a total of 485 participants (average age = 35.35 years, 51.5% female). Bivariate correlation analysis and hierarchical regression models were then applied on the data to investigate the association between pedestrian attributes and their behavioural intentions. The findings revealed that the TPB and the UTAUT explained 46% and 43% of the variance in intentions to cross a road in front of a fully AV, respectively, with perceived behavioural control (PBC) and subjective/social norms the most significant unique predictors of intentions within the TPB and UTAUT, respectively. The TAM, however, only explained 35% of the variance in intentions to cross a road in front of a fully AV. When added into Step 2 of the hierarchical regression, age accounted for additional variance above the TAM predictors, indicating that younger participants reported higher intentions to cross a road in front of a fully AV than older participants. Age was not a significant predictor of intentions when entered with the predictors of the TPB and UTAUT. This study provides support for the use of these theoretical models to understand pedestrians’ acceptance of AVs.Accepted Author ManuscriptSafety and Security Scienc
The construction of Karen Karnak: The multi-author-function
No full textThis thesis is situated within the comparatively recent developments of Web 2.0 and the emergence of interactive WikiMedia, and explores the mode of authorship within a Read/Write culture compared to that of a Read/Only tradition. The hypothesis of this study is that the role of the audience has become merged with the author, and as such, represents new functions and attributes, distinct from a more conventional concept of authorship, in which the roles of audience and author are more separate. Read/Write and participatory culture, as defined by this study, is focused on collaboration, and includes the influences of D.I.Y. culture, Open-Source practices and the production of text by multiple authors. Multi-authorship presents a re-thinking of several concepts which support the notion of the individual author, since the focus of multi-authorship is not on attribution and ownership of a finished text, but on the continued malleability of a text. Modes of multi-authorship, demonstrated in the use of the pseudonyms Alan Smithee and Karen Eliot, represent declarative authors whose names signify multiple origins, whilst concurrently indicating a distinct body of work. The function of these names form an important context to this study, since primary research involves the construction of an experimental mode of multi-authorship utilising WikiMedia technology and the interaction of thirty nine participants, who are invited to create a body of work under the collective pseudonym Karen Karnak. The data generated by this experiment is analysed using aspects of Michel Foucault's author-function to identify and determine power structures inherent in the WikiMedia context. The interplay of power structures, including concepts such as identity, ownership and the body of work, affect the resulting mode of authorship and contribute to the construction of Karen Karnak, suggesting further areas of research into the emerging multi-author
ACT Family Violence Intervention Program review
No full textThis paper reports on a review of the Australian Capital Territory’s Family Violence Intervention Program, which provides an interagency response to family violence matters.
The scope of the review was to analyse the program’s activities and outcomes using 2007–08 data provided by participating agencies, supported by in-depth interviews with key stakeholders including victims whose matters had been finalised in court. After the completion of this report, additional data from 2008–09 and 2009–10 was made available by some Family Violence Intervention Program (FVIP) participating agencies. Although not within the scope of this evaluation, these data pointed to some preliminary improvements in the FVIP
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