2,304 research outputs found
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
Suspended Sediment and Light Attenuation Characteristics in Singapore Waters
No full textLight is attenuated by materials present in the water column by scattering and absorption. The knowledge of light attenuation and its contributing factors influencing visibility/turbidity is unknown in Singapore waters. This MSc thesis consists of field measurement, laboratory experiment and numerical modelling in 3 parts; parameterisation of light attenuation coefficient? K?_d, numerical modelling of underwater light field and visibility. The objectives of this thesis are; a) to determine the dynamics of optical properties in Singapore waters, b) to investigate factors contributing to light attenuation in Singapore waters and c) to model underwater light field and visibility using Hydrolight and Delft3D WAQ. This first part addresses the dynamics of light attenuation (in relation to low/high tide), the spectral nature of optically significant constituents (water, CDOM, phytoplankton and sediment) as well as the effects of particle size distribution (PSD) to light scattering. For PSD with a higher slope j in N(D) = ?KD?^(-j), the d50 ranges from 7.11 to 9.90 ?m in Singapore Strait representing sediment dominated environment. Higher TSS during low tide is advection dominated while lower TSS during high tide is suspension dominated. Relative contributions of CDOM, chlorophyll and sediment to light attenuation coefficient? K?_d is 1.4 – 6.5 % (average of 3.3 %), 1.3 – 62 % (average of 24 %) and 31.3 – 95.2 % (average of 70 %) respectively. Four (4) empirical equations to predict ? K?_d was developed depending on its optical and physical characteristics. Underwater light field modelling shows that light attenuation depend mostly on the concentration of optically significant constituents and only weakly dependent on light structure, cloud cover and fluorescence. The modelled ? K?_d from Hydrolight ranges from 1.2 to 2.3 m-1 with lower ? K?_d in chlorophyll dominated waters while the empirical estimations underestimate K_(d(PAR)) compared to the modelled ? K?_d from Hydrolight. The modelled Secchi depth, S_d ranges from 0.6 – 1.4m corresponding to euphotic depth z_eu of 2.0 – 3.8 m with deeper z_eu for chlorophyll dominated waters. The modelled visibility is generally lowest during Northeast (NE) followed by Southwest (SW) monsoon and Inter monsoon (IM) period with evidence of spatial homogeneity for all monsoons. The visibility model reproduces the recorded? S?_d reasonably well except for Johor Strait and sheltered areas in WCP due to the fact that some processes are not unaccounted in the model. The ? K?_d variation coincides with SSC variation with no phase difference; the visibility is lowest during spring low tide and highest during neap high tide. Convective interaction between the diurnal and semidiurnal components is important in offshore locations while the non-linearity of tidal propagation contributes in the shallow water of Johor estuary. The residual turbidity in Singapore waters is due to tides (semi diurnal and diurnal spring neap interactions) and non-tides (monsoonal effect) in approximately equal magnitude during monsoons. The results from this thesis are applicable in coastal engineering, ecological and remote sensing.Hydraulic EngineeringCivil Engineering and Geoscience
New (Probabilistic) Derivation of Diaz-Metcalf and Pólya-Szegő Inequalities and Consequences
No full textClassical inequalities of Diaz - Metcalf and Pólya - Szegő are generalized to
probabilistic setting which covers the initial deterministic (both discrete and integral) variants.
From these two inequalities, by the probabilistic derivation method further well -
known inequalities are obtained (that ones by Kantorovich, Rennie and Schweitzer)
Mouvance and the medieval author: re-editing Ancrene Wisse
No full textThe paper discusses the theoretical and practical problems of editing the early thirteenth-century guide for anchoresses, Ancrene Wisse, which (in Paul Zumthor's phrase) is an 'oeuvre mouvante', modified repeatedly from an early stage by its author and others
Tele-operated climbing and mobile service robots for remote inspection and maintenance in nuclear industry
No full textChemical 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
D.S. Merezhkovsky and C.G. Jung: General and Special
No full textВ статье рассмотрены особенности трактовки символа в творчестве Д.С. Мережковского и К.Г. Юнга. Показано влияние идей Мережковского на формирование воззрений К.Г. Юнга, проведен сопоставительный анализ их концепций символа как многозначной и универсальной категории, подчеркнуто значение творчества мыслителей для интерпретации исторических событий и осмысления современной общественной ситуации.The article describes the features of the interpretation of the symbol in the works of D.S. Merezhkovsky and K.G. Jung. The author focuses the attention on the influence Merezhkovsky's ideas on the formation of views of Jung, conducted a comparative analysis their conceptions of symbolism as a multi–valued and universal category, stressed the importance thinkers’ works for the interpret historical events and understanding the contemporary social situation
Fully localised edge states in boundary layers
No full textInvestigation of the laminar-turbulent boundary is performed in a boundary-layer flow. Constant homogeneous suction is applied at the wall in order to prevent the spatial growth of the layer, leading to the parallel Asymptotic Suction Boundary Layer (ASBL). Edge tracking is performed in a large computational domain allowing for full spatial localisation of the structures on the laminar-turbulent separatrix. The obtained dynamics of the state goes through calm and bursting phases. During the latter the structure grows in size, shedding vortices downstream of its core which viscously decay during the calm phases. Comparison with the computation in spatially growing boundary layer is made. The influence of the Reynolds number and the path leading from the edge state to turbulent flow are considered
Bypass transition in boundary layers as an activated process
No full textWe consider the spatio-temporal aspects of the transition to turbulence in a boundary layer above a flat plate exposed to free-stream turbulence. Combining results from the receptivity to free-stream turbulence with the observation of a double threshold from transition studies in e.g. pipe flow we arrive at a physically motivated prediction for the spatial distribution of nucleation events in boundary layers. We use a cellular automaton to implement a complete model for the spatial and temporal evolution of turbulent patches and show that the model reproduces the statistical features of the boundary layer remarkably well. The success of the modeling shows that bypass transition occurs as a spatiotemporally activated process, where transition is triggered by critical fluctuations imported from the free-stream turbulence
[Interview Minutes with D.S. Myer, WRA National Director, March 18, 1944]
No full textMeeting minutes between incarceree-led Tule Lake Camp government and War Relocation Authority Director D.S. [Dillon Seymour] Myer. Question-answer session between Co-ordinating Committee and Myer. Includes questions about legitimacy and self-governance of Co-ordinating Committee, concerns about camp food, employment, and martial law in the camp.The Willard Schmidt collection, documents some of the administrative duties of Willard Schmidt, the Chief of Internal Security for the War Relocation Authority and the Tule Lake incarceration/segregation camp. This collection contains administrative records and photos documenting the Tule Lake camp, the largest incarceration camp with a peak population of 18,789 and with the most turbulent history. In 1943, the camp was turned into a segregation center to house "disloyal" Japanese Americans relocated from other camps based on their answers to a confusing loyalty questionnaire. The camp endured martial law from November 1943- Jan 1944 after escalating protests and unrest. The hostile environment of the camp lead to many incarcerees renouncing their American citizenship upon the end of incarceration, a process which took 14 years to reverse if they did not wish to be deported to Japan
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