1,347 research outputs found
Water flow through tailings dams
No full textWater levels in tailings dams are generally lower than those of standard earth dams. Previously, other authors have shown that embankment geometry and variation in permeability can be responsible for a concave upwards steady state seepage line. These factors are investigated in greater detail using a finite element program to model flow in the saturated portion of the embankment. It is shown that the angle of the upstream slope only has an appreciable effect on the form of the seepage line if the pond is close to the downstream face of the dam. An increasing permeability in the direction of flow and seepage path length are responsible for reducing the height of the seepage line. This effect is demonstrated for both a continuous variation of permeability and a step jump in permeability between the tailings deposit and the dam. Anisotropy of tailings and dam permeability is also investigated. Transient analyses of saturated flow are performed for tailings dams constructed of dry compacted waste. For this case, the seepage line is straight for a constant pond level, and concave upwards for a rising pond and a low dam permeability. The simple computer model also predicts that for a constantly rising pond level, the seepage line advances at a constant rate dependent on the rate of pond rise, and the material properties of the dam. A fully automatic finite element program has been written, combining an adaptive mesh regeneration algorithm and a variable mesh technique. The program is shown to provide both an accurate and precise solution of the free surface problem. A method of automatically generating "square" flow nets by post-processing the finite element data is presented for the first time. Flow nets provide a visual proof of the correctness of the computer model and are a useful aid to other workers
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Letter from C.D. Darlington to Janaki Ammal, 18 January, 1960
No full textLetter from C.D. Darlington to Janaki Ammal. Darlington requests information on criminal castes, which he ultimately used for a section of his controversial trilogy of books, Genetics and Man (1953), The Evolution of Man and Society (1969) and the Little Universe of Man (1978). These books have subsequently received criticism for biological determinism, because of the unsubstantiated emphasis that they placed on biological causes of social behaviour.
Author: C.D. Darlington
Date: 18 January, 1960
Source: Bodleian Library Archives, Folder: MS DARLINGTON/J114
(C) Reproduced with Permission of C.D. Darlington's family</p
A suitable girl : Daṇḍin and a meal on the banks of the Kāverī
No full textIn the sixth ucchvāsa of the Daśakumāracarita, Daṇḍin narrates a short story in which a young man coming from Kāñcī is in search for a bride. He finds the suitable girl in a town on the banks of the Kāverī; her beauty is a sign of auspiciousness, and she proves to be able to cook a full meal only with the aid of a limited amount of rice. As for the meal, the passage is extremely interesting from a documentary point of view, because it describes its preparation in full detail. As well known, Daṇḍin is a Pallava poet, who writes around 700 CE; Kāñcī was the Pallava capital at that time, and the full story appears to take place in Pallava territory. The author must know the recipes he is describing quite well. But, besides providing a pleasant short novel, he almost surely had other aims as well. Daṇḍin is always very precise in locating the adventures of his characters, who quite often are of dubious morality. It is most probable that this perfect wife, and the ‘pure’ meal proposed, are also to be read as a way to extol the virtuous women and the Brahmanic customs of the Pallava country, and thus of the Dravidian South
Change is in the Cards: Competition in the Canadian Debit Card Market
No full textAs new entrants arrive in Canada’s debit card market, rule changes are needed to ensure a level playing field, and to enhance the potential benefits of competition for consumers and merchants. In a study released today, the author assesses the implications of the rapidly changing debit payment landscape. Bergevin makes recommendations for action to ensure that consumers and merchants are protected and that the system can evolve to serve them even better.financial services, debit card market, VISA, MasterCard, Interac
Le prime coordinate giurisprudenziali sulla c.d. "opposizione alla perquisizione negativa"
No full textLa Corte di cassazione fornisce le prime coordinate interpretative sulla c.d. “opposizione alla perquisizione negativa”. La disamina della sentenza pone all’interprete questioni piuttosto serie, che l’autore si propone di esaminare, riflettendo sull’oggetto del sindacato giurisdizionale condotto dal g.i.p., sulla base documentale di quel giudizio, sulla esperibilità del ricorso per cassazione avverso l’ordinanza così adottata, nonché sull’applicabilità del rimedio alle c.d. “perquisizioni speciali”.The Italian Court of Cassation provides the first interpretative coordinates about the remedy so-called ‘Opposition to the negative search’. The judgement leads the jurist to reflect on serious issues, which the author proposes to explain, by examining the object of the judicial review conducted by the judge, the documentary basis of that judgement, the admissibility of the appeal to the Court of Cassation against the judge’s decision, as well as the applicability of the remedy to the so-called ‘special searches’
Bacteriological analysis of water quality in a recreational park pond in Rivers State, Nigeria
No full textBacteriological analysis of a Recreational Park Pond in Port Harcourt was investigated to evaluate the water quality of the pond for recreational purposes. Samples collected from the pond were evaluated for physiochemical and bacteriological study. pH showed a slight alkaline range of 6.66 − 6.94 in sample A and D with a temperature range of 28.6 − 29oC. Samples evaluated for turbidity and salinity showed values of 0.309 − 0.784 NTU and 0.10ppt to 0.32ppt respectively. Similar bacteriological load ranging from 6.9 × 105cfu/ml − 2.1 × 106cfu/ml was observed, with coliform counts ranging from 3.4 × 105 − 1.3×106cfu/ml. Thirteen different bacterial genera were identified in total (Escherichia coli, Salmonella spp., Proteus spp., Citrobacter spp., Klebsiella spp, Bacillus spp., Serratia spp., Pseudomonas spp., Vibrio spp., Enterobacter spp., Staphylococcus aureus, Streptococcus spp., and Staphylococcus spp). Escherichia coli was the most commonly occurring group (14.7%) and Staphylococcus sp the least occurring (2.9%). Varying levels of resistance was noted against the 14 antibiotics tested, with the highest resistance noted against pefloxacin (55.9%) while the lowest resistance was against erythromycin (2.9%). Majority of isolates (67.7%) however had MAR index values less than 0.21, indicative of a source related to low antibiotic use. Despite the association of potentially pathogenic bacteria with this water body, the low level of drug resistance associated with these organisms as well as the MAR index values, could point at these being environmental rather than human strains. Further molecular studies would be advised to confirm this.Keywords: Bacteriological analysis, recreational water, antibiotic resistance, pefloxaci
The Ecology and Palaeoecology of Diatom – Duckweed Relationships
No full textThis thesis focuses on the ecology and palaeoecology of diatom-duckweed relationships and utilises a combined experimental, ecological and palaeoecological approach. In particular, the study sought to determine the potential of the epiphytic diatom Lemnicola hungarica to be utilised as a proxy indicator of past dominance of duckweed (Lemna) in small ponds. To this end, contemporary sampling of epiphytic diatom assemblages from a variety of macrophytes (including multiple samples of free-floating plants) were collected from around the world and analysed for diatom epiphytes. In this study, even despite significant environmental gradients, L. hungarica showed a significant association with free-floating plants (including Lemna spp.) as did Sellaphora seminulum. To determine whether this relationship might be used to infer Lemna-dominance in sediment cores, diatom assemblages were analysed in surface sediments from English Lemna and non-Lemna covered ponds and in a core from a pond (Bodham Rail Pit, eastern England) known to have exhibited periods of Lemna-dominance in the past. In both cases, the data suggested that both L. hungarica and S. seminulum were excellent predictors of past Lemna-dominance. Finally, to infer the consequences of Lemna-dominance for the long-term biological structure and ecosystem function of the Bodham Rail Pit, the sedimentary remains of diatoms, plant pigments, and plant and animal macrofossils were enumerated from two sediment cores. These stratigraphic data were compared with the diatom Lemna-indicator metric which indicated three distinct Lemna cycles. Sediment core analyses suggested major compositional, structural and ecological changes brought about by the Lemna cycles, especially in the submerged macrophyte community and in fish-invertebrate relationships. These data reveal that duckweed proliferation, often brought about by eutrophication and terrestrialisation in ponds, can result in dramatic ecological changes due to a strong physical ecosystem engineering effect
Lagging Behind: Productivity and the Good Fortune of Canadian Provinces
No full textThe good fortune of bountiful natural resources is not enough to ensure rising incomes for Canadians in the long term. Growing labour productivity is the most important determinant of future economic welfare and on that measure, Canada is falling behind its major trading partners. Increasing labour productivity does not mean workers working harder for less money, a common canard. It means more investment in one of three factors: 1) human capital (education or other learning); 2) physical capital (plants or other infrastructure); or 3) technology. Just as an individual’s income is in the long-run dependent on how productive he or she is, so too is that of the nation as a whole. If Canada fails to improve its productivity, the incomes of both individual Canadians and the nation as a whole will fall behind those of other developed countries.Economic Growth and innovation, Canadian provinces, labour productivity
What Does it Cost Society to Raise a Dollar of Tax Revenue? The Marginal Cost of Public Funds
No full textThe marginal cost of public funds measures the welfare loss a society incurs in raising an additional dollar of tax revenue. Tax increases distort economic decisions and erode tax bases because of tax avoidance and tax evasion by taxpayers. This Commentary uses econometric estimates of the effects of higher provincial tax rates on the provinces’ corporate income tax, personal income tax, and sales tax bases to calculate the marginal cost of public funds (MCF) for these taxes. The results indicate that the cost of increasing provincial tax revenues through a corporate tax rate increase is very high, and in some provinces, corporate tax rate reductions in 2006 would have increased the present value of the provincial government’s total tax revenues. The results also suggest that significant welfare gains would accrue from reducing provincial corporate income tax rates. As well, increasing provincial corporate and personal income tax rates can cause significant reductions in federal tax revenues because the federal and provincial governments levy taxes on the same tax bases. Finally, Canada’s system of the equalization grants might reduce the perceived MCF of recipient provinces.Fiscal and Tax Competitiveness, marginal cost of public funds (MCF)
Aboriginal Education in Quebec: A Benchmarking Exercise
No full textQuebec’s Aboriginal poverty is severe, and the large gap between Aboriginal and non-Aboriginal education levels is the most important factor in explaining it. In the report, the author examines the relationship between education levels and employment for Quebec Aboriginals. Comparing outcomes within the province’s Aboriginal identity groups to results for other Quebecers, and for Canadians overall, Richards finds that the province’s Aboriginal education outcomes rank below the Canadian average, which itself is disturbingly low. Richards makes six broad recommendations to address the crisis in Aboriginal education – in Quebec and the rest of Canada.The Education Papers, Canada, Quebec, Aboriginals, education, employment
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