954 resultados para Folcculation of mud bank seidments
Resumo:
Pressurised slurries of fine-grained sediment expelled from the base of the active layer have been observed in recent years in the High Arctic. Such mud ejections, however, are poorly understood in terms of how exactly climate and landscape factors determine when and where they occur. Mud ejections at the Cape Bounty Arctic Watershed Observatory, Melville Island, Nunavut, were systematically mapped in 2012 and 2013, and this was combined with observations of mud ejection activity and climatic measurements carried out since 2003. The mud ejections occur late in the melt season during warm years and closely following major rainfall events. High-resolution satellite imagery demonstrates that mud ejections are associated with polar semi-desert vegetative settings, flat or low-sloping terrain and south-facing slopes. The localised occurrence of mud ejections appears to be related to differential soil moisture retention.
THE COSTS OF RAISING EQUITY RATIO FOR BANKS Evidence from publicly listed banks operating in Finland
Resumo:
The solvency rate of banks differs from the other corporations. The equity rate of a bank is lower than it is in corporations of other field of business. However, functional banking industry has huge impact on the whole society. The equity rate of a bank needs to be higher because that makes the banking industry more stable as the probability of the banks going under will decrease. If a bank goes belly up, the government will be compensating the deposits since it has granted the bank’s depositors a deposit insurance. This means that the payment comes from the tax payers in the last resort. Economic conversation has long concentrated on the costs of raising equity ratio. It has been a common belief that raising equity ratio also increases the banks’ funding costs in the same phase and these costs will be redistributed to the banks customers as higher service charges. Regardless of the common belief, the actual reaction of the funding costs to the higher equity ratio has been studied only a little in Europe and no study has been constructed in Finland. Before it can be calculated whether the higher stability of the banking industry that is caused by the raise in equity levels compensates the extra costs in funding costs, it must be calculated how much the actual increase in the funding costs is. Currently the banking industry is controlled by complex and heavy regulation. To maintain such a complex system inflicts major costs in itself. This research leans on the Modigliani and Miller theory, which shows that the finance structure of a firm is irrelevant to their funding costs. In addition, this research follows the calculations of Miller, Yang ja Marcheggianon (2012) and Vale (2011) where they calculate the funding costs after the doubling of specific banks’ equity ratios. The Finnish banks studied in this research are Nordea and Danske Bank because they are the two largest banks operating in Finland and they both also have the right company form to able the calculations. To calculate the costs of halving their leverages this study used the Capital Asset Pricing Model. The halving of the leverage of Danske Bank raised its funding costs for 16—257 basis points depending on the method of assessment. For Nordea the increase in funding costs was 11—186 basis points when its leverage was halved. On the behalf of the results found in this study it can be said that the doubling of an equity ratio does not increase the funding costs of a bank one by one. Actually the increase is quite modest. More solvent banks would increase the stability of the banking industry enormously while the increase in funding costs is low. If the costs of bank regulation exceeds the increase in funding costs after the higher equity ratio, it can be thought that this is the better way of stabilizing the banking industry rather than heavy regulation.
Resumo:
From the Founding of the Bank of France to the Present Time
Resumo:
1.This report presents the results of a field study conducted in the ECASA test site nOS in the Pertuis Breton, France. The site is located on the Atlantic West coasts. It is open to the bay of Biscay, but is slightly protected against westerly winds. The bay has been exploited by intertidal mussels culture for centuries. 2. Within the bay, mussels (Mytilus edulis) are cultivated either by the traditional pole technique, around the bay or on longlines in the centre of the bay. The area occupied by these longline s represents 250 ha, and the resulting annual production is 1 000 tonnes of mussels. The average depth at mid tide is of 13.8 m. The sediment is sandy, with a small fraction of mud. 3. The site is subject to several regular monitoring through the local implementation of national networks aiming at protecting the environment and marine resources, on pollutants (RNO), microbiological quality of the waters (REMI), phytoplanktonic toxic species (REPHY) and growth and mortality of molluscs (REMORA). Benthic macrofauna was studied in 1976. 4. Five sampling sations were chosen along a line, starting under the longlines, and at distances of 50, 100, 200, and 400 metres from the area cultivated. A reference station was chosen in a different direction at 2300 metres of the cultivated area. Sampling methods are described in the text. _Sediments were sampled for different analyses: grain size, content in organic matter, total organic carbon and nitrogen, and phytic pigments (chlorophyll a and phaeopigments). Redox were measured in cores. The macrofauna living into the sediment was also sampled. The water column was sampled for physical (temperature, transparency) and chemical parametres, including oxygen content, salinity, organic matter, dissolved nitrogen forms, phosphates and silicates. Results from benthic macrofauna surveys indicate that there were no significant differences between the different stations and the reference station, all being classified as slightly disturbed. The bay is submitted to freshwater runoffs from two adjacent rivers. 7. The sediment is slightly modified by the culture of bivalves. Total organic carbon, total nitrogen, Eh values and pheopigments were significantly higher under the trestles than in any other stations. Other stations often did not differ from the reference station. 8. The effects of shellfish culture on the water column were. However, it was observed a small decrease of the food available to the molluscs near the rearing 9. The DEB model was able to describe and predict adequately the growth of oysters, both in the Baie des Veys and in the Loch Creran. The parametres for its use in other environment are given, but a tuning of one parametre should be performed with the help of authors. 10. Among the indicators and models for use in are as of intertidal bivalve culture, it is recommended to use the sediment quality index, TOC (Total Organic Carbon), redox and pheopigments, in surficial sediment, AMBI for the macrofauna, chlorophyll a contents and nitrogen forms in the water column, and models describing the carrying capacity, filtration rate of molluscs, and a DEB model to predict the growth of molluscs.
THE COSTS OF RAISING EQUITY RATIO FOR BANKS Evidence from publicly listed banks operating in Finland
Resumo:
The solvency rate of banks differs from the other corporations. The equity rate of a bank is lower than it is in corporations of other field of business. However, functional banking industry has huge impact on the whole society. The equity rate of a bank needs to be higher because that makes the banking industry more stable as the probability of the banks going under will decrease. If a bank goes belly up, the government will be compensating the deposits since it has granted the bank’s depositors a deposit insurance. This means that the payment comes from the tax payers in the last resort. Economic conversation has long concentrated on the costs of raising equity ratio. It has been a common belief that raising equity ratio also increases the banks’ funding costs in the same phase and these costs will be redistributed to the banks customers as higher service charges. Regardless of the common belief, the actual reaction of the funding costs to the higher equity ratio has been studied only a little in Europe and no study has been constructed in Finland. Before it can be calculated whether the higher stability of the banking industry that is caused by the raise in equity levels compensates the extra costs in funding costs, it must be calculated how much the actual increase in the funding costs is. Currently the banking industry is controlled by complex and heavy regulation. To maintain such a complex system inflicts major costs in itself. This research leans on the Modigliani and Miller theory, which shows that the finance structure of a firm is irrelevant to their funding costs. In addition, this research follows the calculations of Miller, Yang ja Marcheggianon (2012) and Vale (2011) where they calculate the funding costs after the doubling of specific banks’ equity ratios. The Finnish banks studied in this research are Nordea and Danske Bank because they are the two largest banks operating in Finland and they both also have the right company form to able the calculations. To calculate the costs of halving their leverages this study used the Capital Asset Pricing Model. The halving of the leverage of Danske Bank raised its funding costs for 16—257 basis points depending on the method of assessment. For Nordea the increase in funding costs was 11—186 basis points when its leverage was halved. On the behalf of the results found in this study it can be said that the doubling of an equity ratio does not increase the funding costs of a bank one by one. Actually the increase is quite modest. More solvent banks would increase the stability of the banking industry enormously while the increase in funding costs is low. If the costs of bank regulation exceeds the increase in funding costs after the higher equity ratio, it can be thought that this is the better way of stabilizing the banking industry rather than heavy regulation.
Resumo:
The purpose of this research is to study sedimentation mechanism by mathematical modeling in access channels which are affected by tidal currents. The most important factor for recognizing sedimentation process in every water environment is the flow pattern of that environment. It is noteworthy that the flow pattern is affected by the geometry and the shape of the environment as well as the type of existing affects in area. The area under the study in this thesis is located in Bushehr Gulf and the access channels (inner and outer). The study utilizes the hydrodynamic modeling with unstructured triangular and non-overlapping grids, using the finite volume, From method analysis in two scale sizes: large scale (200 m to 7.5km) and small scale (50m to 7.5km) in two different time durations of 15 days and 3.5 days to obtain the flow patterns. The 2D governing equations used in the model are the Depth-Averaged Shallow Water Equations. Turbulence Modeling is required to calculate the Eddy Viscosity Coefficient using the Smagorinsky Model with coefficient of 0.3. In addition to the flow modeling in two different scales and the use of the data of 3.5 day tidal current modeling have been considered to study the effects of the sediments equilibrium in the area and the channels. This model is capable of covering the area which is being settled and eroded and to identify the effects of tidal current of these processes. The required data of the above mentioned models such as current and sediments data have been obtained by the measurements in Bushehr Gulf and the access channels which was one of the PSO's (Port and Shipping Organization) project-titled, "The Sedimentation Modeling in Bushehr Port" in 1379. Hydrographic data have been obtained from Admiralty maps (2003) and Cartography Organization (1378, 1379). The results of the modeling includes: cross shore currents in northern and north western coasts of Bushehr Gulf during the neap tide and also the same current in northern and north eastern coasts of the Gulf during the spring tide. These currents wash and carry fine particles (silt, clay, and mud) from the coastal bed of which are generally made of mud and clay with some silts. In this regard, the role of sediments in the islands of this area and the islands made of depot of dredged sediments should not be ignored. The result of using 3.5 day modeling is that the cross channels currents leads to settlement places in inner and outer channels in tidal period. In neap tide the current enters the channel from upside bend of the two channels and outer channel. Then it crosses the channel oblique in some places of the outer channel. Also the oblique currents or even almost perpendicular current from up slope of inner channel between No. 15 and No. 18 buoys interact between the parallel currents in the channel and made secondary oblique currents which exit as a down-slope current in the channel and causes deposit of sediments as well as settling the suspended sediments carried by these currents. In addition in outer channel the speed of parallel currents in the bend of the channel which is naturally deeper increases. Therefore, it leads to erosion and suspension of sediments in this area. The speed of suspended sediments carried by this current which is parallel to the channel axis decreases when they pass through the shallower part of the channel where it is in the buoys No.7 and 8 to 5 and 6 are located. Therefore, the suspended sediment settles and because of this process these places will be even shallower. Furthermore, the passing of oblique upstream leads to settlement of the sediments in the up-slope and has an additional effect on the process of decreasing the depth of these locations. On the contrary, in the down-slope channel, as the results of sediments and current modeling indicates the speed of current increases and the currents make the particles of down-slope channel suspended and be carried away. Thus, in a vast area of downstream of both channels, the sediments have settled. At the end of the neap tide, the process along with circulations in this area produces eddies which causes sedimentation in the area. During spring some parts of this active location for sedimentation will enter both channels in a reverse process. The above mentioned processes and the places of sedimentation and erosion in inner and outer channels are validated by the sediments equilibrium modeling. This model will be able to estimate the suspended, bed load and the boundary layer thickness in each point of both channels and in the modeled area.
Resumo:
Resuspension of the top few sediment layers of tidal mud flats is known to enhance planktonic biomass of microbiota (benthic diatoms and bacteria). This process is mainly controlled by tidal shear stress and cohesiveness of mud, and is also influenced by bioturbation activities. Laboratory experiments in a race track flume were performed to test the interactive effects of these factors on both the critical entrainment and resuspension kinetics of microbiota from silt-clay sediments from the Marennes-Oleron Bay, France. The marine snail Hydrobia ulvae was used to mimic surface bioturbation activities. As expected, the kinetics of microbial resuspension versus shear stress were largely controlled by the cohesiveness of silt-clay sediments. However, our results indicate that the effect of surface tracking by H. ulvae on microbial resuspension was clearly dependent on the interaction between sediment cohesiveness and shear velocity. Evidence was also found that microphytobenthos and bacteria are not simultaneously resuspended from silt-clay bioturbated sediments. This supports the theory that diatoms within the easily eroded mucus matrix behave actively and bacteria adhering to fine silt particles eroded at higher critical shear velocities behave passively.