2,592 research outputs found
The impact of mobile disarticulated shells of Cerastoderma edulis on the abrasion of a cohesive substrate
No full textAn annular laboratory flume was used to investigate the effect of mobile cockle shells on the erosion of a cohesive sediment bed. A standard clay bed was created and shells of differing sizes placed upon it. Flow in the flume was increased in increments and the onset of motion and transport pattern of the cockles was monitored. The release of bed material to the water column was monitored and compared to releases in the absence of shells (due only to the flow). The shells moved in traction; firstly as surface load (dragging) and then by rolling. The motion of the shells was found to be directly related to their motion settling rate in still water. The fluid induced stresses were unable to cause any detectable erosion of the bed. The addition of even single shells induced significant erosion. The erosion was found to be the result of abrasion rather than corrosion, as the shells never entered into saltation. There was a linear increase in erosion rate with increasing shell size, and an exponential increase in the suspended sediment concentration with time. The presence of large numbers of cockle shells in areas such as Southampton water and Lymington have suggested that the processes investigated here may be responsible for the erosion regimes in these areas
Domain Names in Turkey
No full textTurkey faces both unique and common domain name regulatory issues. In this paper, the author focuses on the challenges ahead for Turkey, with especial focus on the regulation of IDNs
Plagiarism: concepts and contexts
No full textAfter outlining the key difficulties in modern literature on academic plaigarism, the author suggests that these may be resolved by a new model of plaigarism (whilst noting that this new model does raise additional uncertainties, e.g. as to the status of 'self plagiarism') that she has developed
Dictionary of Acoustics
No full textThe science and technology of acoustics embraces an unusually wide range of disciplines, from aircraft noise reduction to ultrasonics in medicine, from psychoacoustics to signal processing. The student of acoustics has to become familiar with a corresponding range of specialist terms in order to communicate with others and to understand the literature. Here, in one informative dictionary, for the first time, are listed accurate and helpful definitions to provide the student - or the specialist from another discipline - with a point of entry into the world of acoustics. The dictionary's 2,800 entries cover most of the essential concepts and terminology that the practicing acoustician needs to understand, outside the subfields of music and speech communication. The author has drawn on experience gained during a long career spent mostly at Southampton University's multidisciplinary Institute of Sound and Vibration Research, supplemented by the expertise and perspective of a team of subject specialists
Also By The Same Author: AKTiveAuthor, a Citation Graph Approach to Name Disambiguation
No full textThe desire for definitive data and the semantic web drive for inference over heterogeneous data sources requires co-reference resolution to be performed on those data. In particular, name disambiguation is required to allow accurate publication lists, citation counts and impact measures to be determined. This paper describes a graph-based approach to author disambiguation on large-scale citation networks. Using self-citation, co-authorship and document source analyses, AKTiveAuthor clusters papers, achieving precision of 0.997 and recall of 0.818 over a test group of eight surname clusters
Sea surface temperature trends in the coastal ocean
No full textSea surface temperature (SST) trends in the coastal zone are shown to be increasing at rates that exceed the global trends by up to an order of magnitude. This paper compiles some of the evidence of the trends published in the literature. The evidence suggests that urbanization in the coastal hinterland is having a direct effect on SST through increased temperatures of river and lake waters, as well as through heated run-off and thermal effluent discharges from coastal infrastructure. These local drivers of SST are compounded by regional drivers manifest as changing weather patterns (latent heat exchange) and direct radiative heating of shallow coastal waters (particularly in restricted embayments and seas). Thus the impact of urbanization on SST may extend well beyond the much-popularised impact of “greenhouse gasses”. The Marine Climate Change Impacts Partnership Report [37] stated that our capacity to define and predict long-term coastal changes due to anthropogenic causes is “unknown” and confidence in results is “low”. This is a major barrier to planning for inevitable changes in coastal climate that are likely to take place over the coming decades
Chemical trends at lakes and streams in the UK Acid Waters Monitoring Network, 1988-2000: evidence for recent recovery at a national scale
No full textA detailed trend analysis of 12 years of data (1988-2000) for 22 surface waters in acid-sensitive regions of the United Kingdom, in which individual site data have been combined to identify national-scale trends, has shown strong common patterns of temporal variation. Results suggest a widespread reduction in sulphate concentrations, hydrogen ion and inorganic aluminium species, and increases in acid neutralising capacity. Many chemical changes have not been linear. However, the first five years were characterised by high concentrations of marine ions and relatively stable pollutant sulphate concentrations and the remaining period by lower concentrations of marine ions and declining sulphate. Genuine "recovery", in terms of declining acidity in response to reduced anthropogenic sulphur deposition is only apparent, therefore, for the latter part of the monitoring period. Reductions in calcium concentrations appear to have partially offset the influence of sulphate reductions on acidity, as have increases in organic acidity associated with strong and widespread rising trends in dissolved organic carbon. Fluctuations in a number of climatic factors over the monitoring period have led to significant inter-annual variability in nitrate, which exhibits little long-term trend, marine ions and acidity, emphasising the need for long monitoring periods if underlying trends are to be correctly identified
Spatial and temporal water chemistry data and organic matter composition from UK surface waters, 2018-2021
No full textThis dataset contains water chemistry and organic matter composition variables. Water chemistry variables include pH, conductivity, dissolved oxygen, dissolved organic carbon, nutrients, anions, cations and metal concentrations. Organic matter composition variables include metrics calculated from carbon, nitrogen, hydrogen and oxygen concentrations. Water samples were collected from UK surface waters between 2018 and 2021. Water was collected from each site either annually, seasonally or monthly, to determine how organic matter varies over time and space. Site metadata include land use and vegetation cover, catchment area and percentage peat cover. Exact locations of sites are not included, and site names are anonymised.Moody, C.S.; Bell, N.G.A.; Mackay, C.L.; Kitson, E.; Gasior, R.L.; Hunt, S.F.P.; Greenwood, J.G.; Ashley, D.J. (2025). Spatial and temporal water chemistry data and organic matter composition from UK surface waters, 2018-2021. NERC EDS Environmental Information Data Centre. https://doi.org/10.5285/ada28810-040b-4fef-8669-b21bac64a10
Introduced marine biota in Western Australian waters
No full textAn annotated compendium is presented of 102 species of marine algae and animals that have been reported as introduced into Western Australian marine and estuarine waters, four of which arc on the Australian national list of targeted marine pest species. For each species the authority, distribution (both in Western Australia and elsewhere), voucher specimen(s) and remarks are given. Sixty species are considered to have been introduced through human activity, including three on the list of Australian declared marine pests. The most invasive groups are: bryozoans (15 species), crustaceans (13 species) and molluscs (9 species). Seven of these introduced species, including four natural introductions, have not been found recently and are not presently considered to be living in Western Australia. Twenty six species are regarded as cryptogenic or native. The records of nine species, including two declared marine pests, are questionable or rejected.
The distribution of the 60 introduced species shows that most (37) are temperate species that occur from Geraldton south; only 6 are tropical species that occur from Shark Bay north; 17 introduced species occur in both the southern and northern halves of Western Australia, Because most of the introduced species are temperate species, southern marine areas have more introduced marine species than northern areas. The greatest concentration is in the southwest corner: 46 in Fremantle, Cockburn Sound and the lower Swan River; 25 in Albany and 24 in Bunbury.
We conclude with a strong recommedation that continuing baseline taxonomic research and surveys of the Western Australian marine waters be regarded as an essential component of protecting and managing the State's valuable marine environment
Modelling of turbulent jets and wall layers: extensions of Lighthill's acoustic analogy with application to computational aeroacoustics
No full textTwo extensions to Lighthill’s aeroacoustic analogy are presented. First, equivalent sources due to initial conditions are derived that supplement those due to boundary conditions, as given by Ffowcs Williams & Hawkings. The resulting exact inhomogeneous wave equation is then reformulated with pressure rather than density as the wave variable, and the right-hand side is rearranged using the energy equation with no additional assumptions. Applications to computational aeroacoustics are discussed, and illustrated with examples based on 2D and 3D simulations
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