Dissertations / Theses: 'System margin'

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Le, Anh. "Stratigraphic evolution and plumbing system of the Cameroon margin, West Africa." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/stratigraphic-evolution-and-plumbing-system-of-the-cameroon-margin-west-africa(94a13f64-a927-47b6-b456-a0b57c0e5494).html.

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The Kribi-Campo sub-basin is the northernmost of a series of Aptian basins along the coast of West Africa. These extensional basins developed as a result of the northward progressive rifting of South America from West Africa, initiated c. 130 Ma ago. Post-rift sediments of the Kribi-Campo sub -basin contain several regional unconformities and changes in basin-fill architecture that record regional tectonic events. The tectono-stratigraphic evolution and plumbing system has been investigated using a high-quality 3D seismic reflection dataset acquired to image the deep-water Cretaceous-to-Present-day post-rift sediments. The study area is located c. 40 km offshore Cameroon in 600 to 2000 m present-day water depth, with full 3D seismic coverage of 1500 km2, extending down to 6.5 seconds Two-Way Travel time. In the late Cretaceous the basin developed as a result of tectonism related to movement of the Kribi Fracture Zone (KFZ), which reactivated in the late Albian and early Senonian. This led to inversion of the early syn-rift section overlying the KFZ to the southeast. Two main fault-sets - N30 and N120 - developed in the center and south of the basin. These normal faults propagated from the syn-rift sequences: the N120 faults die out in the early post-rift sequence (Albian time) whilst N30 faults tend to be associated with the development of a number of fault-related folds in the late Cretaceous post-rift sequence, and have a significant control on later deposition. The basin is filled by Upper Cretaceous to Recent sediments that onlap the margin. Seismic facies analysis and correlation to analogue sections suggest the fill is predominantly fine-grained sediments. The interval also contains discrete large scale channels and fans whose location and geometry were controlled by the KFZ and fault-related folds. These are interpreted to contain coarser clastics. Subsequently, during the Cenozoic, the basin experienced several tectonic events caused by reactivation of the KFZ. During the Cenozoic, deposition was characterized by Mass Transport Complexes (MTCs), polygonal faulting, channels, fans and fan-lobes, and aggradational gullies. The main sediment feeder systems were, at various times, from the east, southeast and northeast. The plumbing system shows the effects of an interplay of stratigraphic and structural elements that control fluid flow in the subsurface. Evidence for effective fluid migration includes the occurrence of widespread gas-hydrate-related Bottom Simulating Reflections (BSRs) 104 - 250 m below the seabed (covering an area of c. 350 km2, in water depths of 940 m - 1750 m), pipes and pockmarks. Focused fluid flow pathways have been mapped and observed to root from two fan-lobe systems in the Mid-Miocene and Pliocene stratigraphic intervals. They terminate near, or on, the modern seafloor. It is interpreted that overpressure occurred following hydrocarbon generation, either sourced from biogenic degradation of shallow organic rich mudstone, or from effective migration from a thermally mature source rock at depth. This latter supports the possibility also of hydrocarbon charged reservoirs at depth. Theoretical thermal and pressure conditions for gas hydrate stability provide an opportunity to estimate the shallow geothermal gradient. Variations in the BSR indicate an active plumbing system and local thermal gradient anomalies are detected within gullies and along vertically stacked channels or pipes. The shallow subsurface thermal gradient is calculated to be 0.052 oC m-1. With future drilling planned in the basin, this study also documents potential drilling hazards in the form of shallow gas and possible remobilised sands linked with interconnected and steeply dipping sand bodies.

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Sumawong, Anannit. "Risk management of energy derivatives : hedging and margin requirements." Thesis, University of Sussex, 2014. http://sro.sussex.ac.uk/id/eprint/53818/.

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The recent growth of exchanges has generated large trading platforms for investors. The largest of these institutions, the Intercontinental Exchange and the Chicago Mercantile Exchange group are now responsible for clearing trades for the majority of investors worldwide and are perhaps, as large commercial banks are, too big to fail. This has attracted attention from international regulating bodies to impose strict risk management standards on the exchanges to ensure financial stability. In this thesis, we identify first, that an investor in the market is strongly affected by margins set by the exchanges in determining the transaction costs of a trade. We discuss the possibility that a volatile margin movement would introduce further risks for such an investor causing them to raise more capital to cover possible margin calls which can perhaps lead to procyclicality. We follow this work by addressing how margins can be determined in adherence to the new laws. Exchanges are now required to set margins based on the Value-at-Risk, hence we search for the best Value-at-Risk method for margining use. Here, we find that the simple Orthogonal Exponentially Weighted Moving Average method is sufficient in forecasting the Value-at-Risk, which contradicts a fair body of the literature who suggests that complex developments of GARCH are superior. We then offer methods for setting and evaluating margin requirements upon the Value-at-Risk estimates, concentrating on producing stable margin requirements. The automated methods produced in our work outperform all other methods available in the literature. Furthermore, we are the first to provide methods for assessing margin stability. Our work is timely in addressing the current affairs of the world economy and is among the first to tackle the margin stability issue in detail.

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Demirbas, Nesrin. "Determinants Of Profitability In Turkish Banking System." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12611015/index.pdf.

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This thesis analyses the effect of sectoral and macroeconomic variables on the profitability of the Turkish commercial banks over the period 2005-2009:3 by using multiple regressions. In this study, profitability of Turkish banking system in the mentioned period is discussed and questions such as why some commercial banks are more profitable than others and to what extent discrepancies in banks&rsquo profitability are due to variation in endogenous factors under the control of bank management and to what extent external factors impact the profitability performance of these banks are sought to answer. Firstly, the empirical results revealed that sectoral characteristics explain a substantial part of the within country variation in bank interest margins and net profitability. High profitability tends to be associated with banks that hold a relatively high amount of equity capital, and with large non interest income. Other important internal determinants of banks&rsquo profitability are non-interest expenses and fixed assets which have negative and significant impact. Also, equity capital is the internal determinant of net interest margin. Secondly, it is found that inflation is the macroeconomic determinant of net interest margin and profitability.

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Dimopoulos, Ilias. "A nonlinear study of the gain margin of a third order regulator system." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1993. http://handle.dtic.mil/100.2/ADA277296.

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Krishnan, Anaga. "Robustness and Stability Analysis with a Heavily-Meshed Distribution Network." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/89905.

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Power distribution systems continue to evolve to accommodate the advancements in the field of microgrids and renewable energy resources. The future grids will be highly connected and will require increased reliability of the network. To this effect, low-voltage distribution systems with meshed or networked topology can be utilized. Currently, the use of low-voltage heavily-meshed distribution systems is restricted to urban areas with high load density that require increased reliability of power. A reason for this is the high cost of construction of such systems and complex topology which creates additional challenges. The direction of power flow in such systems is not unidirectional, which makes the power flow analysis difficult. Complicated network analysis techniques are required to determine the fault currents and protection settings in the network. Due to the aforementioned reasons, there is limited work analyzing the effectiveness of existing power flow algorithms to solve complex meshed systems. In this thesis, the robustness of two power flow algorithms is compared using an index called static stability breakdown margin parameter of circuit elements. For this study, a low-voltage heavily-meshed distribution test system is also proposed. Additionally, a study is conducted to show how reliable the meshed test system is against any fault in the system. The steady-state voltage stability of the test system is observed during the event of a fault. The stability margin parameter is then used to determine the vulnerable components in the system which need to be strengthened to increase the stability and voltage profile of the system. Master of Science Distribution systems carry electricity from the transmission system and deliver it to the customers. Distribution systems mainly operate using two topologies for their feeders: Radial and Meshed. The majority of customers are served using radial distribution systems, as in the radial feeders power flows in one direction (i.e. from substation to the end-user). They are simple in design and operation and are constructed at a moderate cost. However, if there is a fault along the main feeder, there will be an interruption of power to the end-use customer. On the other hand, meshed distribution systems involve multiple paths of power flow between all the points in the network. If a fault occurs along the feeder, the power flow is rerouted to the other available paths. Thus, Heavily Due to their complex topology, meshed systems are expensive to construct and deploy. The power flow analysis of these systems poses many challenges. Because of these reasons, their use is mainly restricted to urban areas with high load density which require very high reliability. The future grid is becoming increasingly complex and evolving to a meshed distribution topology has its own advantages. However, as presently the use of meshed systems is sparse, the work done on evaluating the stability of these systems is minimal. As a result of which, this thesis focuses on determining the optimal power flow solvers for these complex systems, analyzing their stability under abnormal operating conditions, and suggesting methods to reinforce the vulnerabilities in the system.

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Fu, Yanzhe [Verfasser]. "Numerical modeling of an overpressured petroleum system, Kristin Field, Mid-Norwegian margin / Yanzhe Fu." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2010. http://d-nb.info/1034994875/34.

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Makeche, Sombo. "Analysing trader behaviour in the maize marketing system in Zambia." Diss., University of Pretoria, 2016. http://hdl.handle.net/2263/60829.

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traders are perceived to extract monopoly rents from farmers by offering very low prices. However, little attempt has been made to understand the behaviour of private traders and the factors that influence their behaviour. This study, therefore, examines the behaviour of private traders and determines the factors influencing their behaviour by means of the Chi-squared test. It further identifies the characteristics of smallholder farmers and private traders transacting with each other and examines the pricing, grading and weighting systems used by private traders, as well as the relationship that exists between farmers and private traders. Understanding private trader behaviour, factors influencing this behaviour, and the relationship between farmers and these private traders are important questions and have great implications for policy. Primary data was used in this study which involved interviews and direct observations with both private traders and smallholder farmers. The sample sizes for private traders and smallholder farmers were 50 and 200, respectively. The data was collected in the Kalomo District of Zambia between June and August, 2015. Only those farmers that transact with private traders or use assembly traders as the marketing channel were included in this study. The data collected was analysed using gross marketing margin, the Chi-squared test and descriptive statistics. The measure of the extent of opportunistic behaviour was also used to achieve the study objectives. The findings show that the mean price paid by private traders was ZMW 0.989 (USD 0.13) per kg and private traders were the ones who determine the prices and grades of maize. The private traders also weigh the maize and the smallholder farmers have little control on the final weight of the maize, as they do not participate in the weighing. This indicates that the private traders have power in the determination of the weight of maize. The majority of the private traders were found to behave opportunistically, accounting for 58 % of the surveyed traders. Experience and education level of the private traders were found to influence their behaviour. Given the importance of the above factors in influencing private trader behaviour, particularly experience and education, the results suggest that monitoring of the maize trading could potentially significantly reduce opportunistic behaviour among these less-experienced and less-educated traders. Lastly, the study reveals that 68.5 % of the smallholder farmers did not trust the private traders, whereas 46 % of the private traders did trust the farmers. The findings of this study indicate great potential for public sector investments in organisations that ensure standard weights (such as the Zambia Weights and Measures Agency 'ZWMA') and grades for maize. The ZWMA is the Zambian organisation responsible for enforcing weight institutions. An agency enforcing grading institutions for the smallholder maize farmers, however, does not exist in Zambia. Investment in such organisations would increase the levels of trust between farmers and traders, as neither would be suspicious of the weight or grade obtained, and possible opportunistic behaviour would be reduced. The suggestions and recommendations given by this study should help reduce the possibilities for opportunistic behaviour and exploitation of smallholder farmers. Because this study is in line with Zambia's poverty reduction plan to reduce poverty levels through increased agricultural production and improved maize trading among smallholder farmers, the recommendations given will help improve maize trading and the livelihoods of smallholder farmers. This is because they will be able to sell their maize at higher prices owing to reduced opportunistic behaviour of private traders, thus realising profits. The development of a grading system will lead to a better trading environment for both smallholder farmers and private traders, as both parties will be certain of the maize quality. In conclusion, a trading environment where organisations and institutions are in place, monitored and enforced to ensure reliable grading and weighing systems will help improve maize trading by smallholder farmers and private traders in Zambia. The improved maize trading will be the result of reduced opportunistic behaviour. This will ultimately increase the welfare of smallholder farmers and improve their livelihoods, which will contribute towards the reduction of the poverty levels in Zambia. Dissertation (MSc (Agric))--University of Pretoria, 2016. Agricultural Economics, Extension and Rural Development MSc (Agric) Unrestricted

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Afonso, Lutcy Menezes. "Correcting for attrition in panel data using inverse probability weighting : an application to the european bank system." Master's thesis, Instituto Superior de Economia e Gestão, 2015. http://hdl.handle.net/10400.5/8155.

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Mestrado em Econometria Aplicada e Previsão Esta dissertação analiza técnicas de correção do efeito do enviesamento que pode ocorrer no caso dos dados utilizados apresentarem valores em falta. Tais técnicas serão aplicadas a um modelo económico para caracterização da margem líquida de juros (MLJ) bancária, utilizando dados provinientes 15 países que pertencem ao sistema bancário da União Europeia (UE15). As variáveis que caracterizam os bancos são observados entre de 2004 e 2010. E são escolhidas seguindo Valverde et al. (2007). Adicionalmente aos regressores são acrescentadas algumas variáveis macroeconómicas. A seleção proviniente da falta de alguns valores para os regressores é tratada através da ponderação probabilistica inversa. Os ponderadores são aplicados a estimadores GMM para um modelo de dados de painel dinámico. This thesis discusses techniques to correct for the potentially biasing effects of missing data. We apply the techniques on an economic model that explains the Net Interest margin (NIM) of banks, using data from 15 countries that are part of the European Union (EU15) banking system. The variables that describe banks cover the period 2004 and 2010. We use the variables that were also used in Carbó-Valverde and Fernndez (2007). In addition, also macroeconomic variables are used as regressors. The selection that occurs as a consequence of missing values in these regressor variables is dealt with by means of Inverse Probability Weighting (IPW) techniques. The weights are applied to a GMM estimator for a dynamic panel data model that would have been consistent in the absence of missing data.

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Spyres, Georgina. "The biogeochemical cycling of dissolved organic carbon in the Iberian margin upwelling system (NE Atlantic Ocean)." Thesis, University of Plymouth, 2001. http://hdl.handle.net/10026.1/2368.

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Dissolved organic carbon (DOC) is the quantitatively most important organic carbon reservoir in the world's oceans and its determination at ocean margins, where the exchange of terrestrial and oceanic organic matter occurs, is important for estimating cross-slope fluxes to deep waters. With the increased accuracy and precision (-1%) of analytical methodologies, small changes in the DOC pool can be detected (i.e. 1- 2uM-C). This study investigated the biogeochemical cycling of DOC at the Iberian Margin upwelling system (42-43°N, --9-10°W), where contrasting seasonal hydrologic phenomena occur (e.g. summer upwelling, winter poleward current). Spatial and temporal DOC distributions were determined using high temperature catalytic oxidation (HTCO) techniques. DOC concentrations generally decreased with distance from the continental shelf and with increasing depth, although localised accumulation was observed in surface as well as in deep waters with a mean excess of up to 16 uM-C over background concentrations (57 uM-C). DOC concentrations in surface waters were closely associated with bacterial productivity and dissolved organic nitrogen (DON) production was facilitated by photosynthetic extra-cellular release from phytoplankton. There was no marked difference in DOC concentrations between the summer and winter seasons due to increased mineralization during the summer and lateral inputs during the winter. DOC production exceeded removal rates in summer upwelled surface waters following enhanced biological activity, in the winter surface poleward current and in deep waters that contained high levels of suspended particulates. DOC from terrestrial run-off was recycled rapidly at the coast before it could be exported to the shelf Cross-slope export of accumulated DOC was generally hindered by the net onshore velocity component during both winter and summer seasons and by the presence of water masses travelling along-slope.

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Yang, Xiaojing. "Nonlinear Control System Stability Metrics via A Singular Perturbation Approach." Ohio University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1364466371.

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Karki, Sagar. "Effect of DERs on the Voltage Stability of Transmission Systems using a Voltage Stability Index." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/101783.

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Interconnection of DERs into the transmission lines is starting to take a substantial share of the total power capacity. Although the largest share of power generation attributes to coal and gas power plants, renewable energy is gradually increasing. However, in the past, the size of DERs was relatively smaller, and rooftop PV was the dominant renewable energy source. As a result, the studies for interconnection focused on those rooftop PVs on the distribution side. Since the scenario is slowly changing as more utilities increase the share of clean energy by building large-scale solar farms and wind farms, it is necessary to study the effect of those DERs in the transmission system. Among the various issues, this work focuses on the impact on a transmission system's voltage stability. When the voltage stability at a point in the system is compromised, it can affect the entire power system's overall security, quality, and reliability. Therefore, this work aims to assess the system's stress due to increased loading conditions and increased growth of DERs integration. A steady-state voltage stability index is used to generate a heat-map that identifies the areas where the system can go unstable in events like the loss of the renewable generation under a bus. The steady-state simulation is performed on the IEEE 14 bus system in Distributed Engineering Workstation (DEW) to find the system's weak links using the stability heat-map. DERs are added to the corresponding weak buses, and the improvement in the stability margin for various penetration levels are studied. The results obtained from the steady-state analysis are also verified using the dynamic simulation of the model using OpenModelica. Master of Science Transmission networks are going through some of the fundamental changes in how they are planned and operated as more and more renewable energy sources are connected to the grid. Unlike the traditional setup where the transmission line transfers bulk power from a large generator to the load center at a different location, the advent of renewable energy resources enables the power to be generated in distributed form. It allows electrical power to be generated closer to the demand. In the long run, the transmission system's stress reduces as a significant portion of demand is supplied locally. Thus, the distributed energy resources (DERs) in the power grid have the potential for substantial economic and environmental benefits. However, it can also bring about a range of challenges to the power system. Among the various issues, this work focuses on the effects on a transmission system's voltage stability. When the voltage stability at a point in the system is compromised, it can affect the entire power system. Therefore, this work aims to assess the stress on the system due to increased loading conditions and increased growth of DERs integration, utilizing a voltage stability index to identify the areas where the system can go unstable in events like the loss of renewable generation under a bus. The steady-state simulation is performed on the IEEE 14 bus system to find the weak links in the system where DERs can improve the system's stability. The results obtained from the steady-state analysis are verified using the dynamic simulation of the model.

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Mahanjane, Estevão Stefane [Verfasser]. "The evolution of the East African margin offshore Mozambique : geotectonic history and petroleum system analysis / Estevão Stefane Mahanjane." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2014. http://d-nb.info/1059371464/34.

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Kang, Yong Suk. "Development of Predictive Vehicle Control System using Driving Environment Data for Autonomous Vehicles and Advanced Driver Assistance Systems." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/85106.

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In the field of modern automotive engineering, many researchers are focusing on the development of advanced vehicle control systems such as autonomous vehicle systems and Advanced Driver Assistance Systems (ADAS). Furthermore, Driver Assistance Systems (DAS) such as cruise control, Anti-Lock Braking Systems (ABS), and Electronic Stability Control (ESC) have become widely popular in the automotive industry. Therefore, vehicle control research attracts attention from both academia and industry, and has been an active area of vehicle research for over 30 years, resulting in impressive DAS contributions. Although current vehicle control systems have improved vehicle safety and performance, there is room for improvement for dealing with various situations. The objective of the research is to develop a predictive vehicle control system for improving vehicle safety and performance for autonomous vehicles and ADAS. In order to improve the vehicle control system, the proposed system utilizes information about the upcoming local driving environment such as terrain roughness, elevation grade, bank angle, curvature, and friction. The local driving environment is measured in advance with a terrain measurement system to provide terrain data. Furthermore, in order to obtain the information about road conditions that cannot be measured in advance, this work begins by analyzing the response measurements of a preceding vehicle. The response measurements of a preceding vehicle are acquired through Vehicle-to-Vehicle (V2V) or Vehicle-to-Infrastructure (V2I) communication. The identification method analyzes the response measurements of a preceding vehicle to estimate road data. The estimated road data or the pre-measured road data is used as the upcoming driving environment information for the developed vehicle control system. The metric that objectively quantifies vehicle performance, the Performance Margin, is developed to accomplish the control objectives in an efficient manner. The metric is used as a control reference input and continuously estimated to predict current and future vehicle performance. Next, the predictive control algorithm is developed based on the upcoming driving environment and the performance metric. The developed system predicts future vehicle dynamics states using the upcoming driving environment and the Performance Margin. If the algorithm detects the risks of future vehicle dynamics, the control system intervenes between the driver's input commands based on estimated future vehicle states. The developed control system maintains vehicle handling capabilities based on the results of the prediction by regulating the metric into an acceptable range. By these processes, the developed control system ensures that the vehicle maintains stability consistently, and improves vehicle performance for the near future even if there are undesirable and unexpected driving circumstances. To implement and evaluate the integrated systems of this work, the real-time driving simulator, which uses precise real-world driving environment data, has been developed for advanced high computational vehicle control systems. The developed vehicle control system is implemented in the driving simulator, and the results show that the proposed system is a clear improvement on autonomous vehicle systems and ADAS. Ph. D.

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Nair, Nisha. "Geophysical characterization of tectonic elements along the western continental margin of India and the Andaman-Sumatra Arc- Trench system." Thesis, IIG, 2010. http://localhost:8080/xmlui/handle/123456789/1583.

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BLONDEL, SIMON. "Seismic Imaging and Salt Tectonics of the Mediterranean Salt Giant in the Central Algerian Basin." Doctoral thesis, Università degli Studi di Trieste, 2022. http://hdl.handle.net/11368/3030773.

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The Mediterranean Salt Giant (MSG) is a thick layer of Messinian evaporites (up to 4 km) that is thought to be deposited during an extreme paleo-environmental event known as the Messinian Salinity Crisis (MSC). After decades of research, there is not yet a consensual model explaining the emplacement and the evolution of the MSG. This is due to the absence of samples of the deep offshore MSG. Past scientific drilling operations were limited to the topmost MSG records because of the risks of intersecting zones of hazardous fluids and overpressure linked to evaporites. The European project SALTGIANT, in which the work of this thesis fits into, is dedicated to understanding the formation of the MSG and its implications for the microbial life, the drilling hazards and the geo-economics of the Mediterranean region and the history of oceanography. In that framework, this thesis aims to improve our seismic images of the offshore MSG and to use the new results to update our understanding of the Messinian salt tectonics. This work is focused on the Algerian basin, in the south-western Mediterranean Sea, where the salt was deposited in an already contractional tectonic setting. I compile, reprocess, and interpret legacy academic seismic data acquired in the central Algerian basin. The re-processing is designed to improve as much as possible the salt and pre-salt structures. It relies on an integrated approach combining geophysics and geological interpretation to iteratively build the velocity model. The new results display a better imaging of salt structures and the seismic facies variations. They shed a new light on the tectono-sedimentary evolution of the central Algerian basin, highlighting the presence of seismic fluid indicators evidencing an active fluid circulation in the basin and its margins. Interpretation of the new seismic sections is done following the most recent nomenclature of the MSC seismic markers. New isochores and thickness maps are produced and compared with the spatial distribution of the salt structures. I interpret contractional salt tectonic structures, such as buckle folds, squeezed diapirs and related salt sheets as evidence of regional thick-skinned shortening episodes. I suggest that extensional stage of the salt system (where the deformation is driven by gravity loading) was short-lived, and that many salt structures were driven by contractional tectonic loading during the Plio-Quaternary. I demonstrate that the initial shortening-related salt deformation in the late Messinian was focussed along the Algerian margin and later shifted outward toward the Balearic margin in the Plio-Quaternary. The shifting of the deformation front is interpreted to be a result of the thickening and strengthening of the overburden. The second peak of deformation may have reactivated faults along the Emile-Baudot escarpment with thick-skinned deformation. I also observe a variation in the intensity of the salt deformation along the margin from SW to NE, which I associate to variable tectonic loading applied along the Algerian margin or the pre-shortening distribution of salt. Fluid indicators are imaged within the Plio-Quaternary of the Algerian basin. They could be thermogenic or biogenic gas sourced from the Messinian Upper Unit, or from the pre-salt, migrating through a hydro-fractured salt. The new results also evidence numerous volcanic structures within the Formentera basin. The distribution of this volcanic edifice could affect fluid circulation, resulting in small-wavelength surface HF anomalies observed locally.

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Bazeley, Katherine Mary. "Controls on jökulhlaup impact during a period of glacier margin recession, Blautakvísl-Súla river system, south-east Iceland (1996-2010)." Thesis, University of Newcastle Upon Tyne, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580319.

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Glacier outburst floods (jokulhlaups) comprise major hazards in Iceland and can have considerable impact on the surrounding environment and infrastructure due to their ability to erode, transport and deposit large volumes of sediment. Greater knowledge of jokulhlaup processes will therefore improve our ability to mitigate their impacts. This investigation aims to determine the controls on jokulhlaup impacts within the Blautakvisl-Sula river system, south-east Iceland. The Blautakvisl-Sula drains the western margin of Skeioararjokull; a surge-type outlet glacier of the Vatnajokull ice cap. The margin of Skeioararjokull has been in recession since its last surge in 1991. A literature-based model of the controls on jokulhlaup impact at a receding glacier margin is developed and tested. Although models of the geomorphological impacts of glacier margin recession on proglacial areas exist, none are specific to jokulhlaups. Therefore this study is important for conceptualising the impacts of jokulhlaups on proximal glacial environments. Glacier margin recession plays both a direct and indirect role in affecting the impacts of jokulhlaups on the Blautakvisl-Sula system. It has resulted in a change in the drainage pattern of the system, with flood waters being routed progressively eastwards since 1996. Ice surface lowering at the snout of the glacier and changes in the drainage mechanism of Graenalon ice-dammed lake have also affected jokulhlaup cyclicity, magnitude, frequency and routing. Geomorphological maps produced as part of this research show that the east of the system has become more heavily impacted by jokulhlaups than the west of the system over the past 15 years, as the ice front lowers and causes ponding of water in the west. Sedimentological data provides evidence as to how recent floods have been of progressively lower magnitude, and have had less impact on the geomorphology of the Blautakvisl-Sula system as a whole than previous episodes in the record. Existing models of the impacts of glacier margin recession on flood systems have suggested that some systems 'decouple' from their feeder system as they recede. This study however, finds that Skeioararjokull shows evidence of being coupled to the sandur, despite the glacier being in recession. This study therefore identifies an additional state of 'coupled recession' as a transitional phase between a 'coupled' and 'lowering' system. The resultant model can potentially be of use for other glacier systems worldwide in conceptualising jokulhlaup impacts on the proximal sandur.

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Akhmetova, Gaukhar. "Hydraulic and thermal modelling in faulted geological systems, application for the site U1517 of Hikurangi Margin, New Zealand, and Enhanced Geothermal System of Soultz-sous-Forêts." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0307.

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Pour un certain nombre d'applications géoscientifiques, la compréhension des mécanismes de transport dans les systèmes géologiques naturellement fracturés et faillés suscite une grande attention. Les systèmes de zones de failles jouent un rôle important dans l'écoulement des fluides de subsurface dans de nombreux processus géologiques et hydrogéologiques. Les propriétés hydrauliques des failles peuvent contrôler l'exploitation des réservoirs géothermiques, la migration des hydrocarbures pétroliers et le transport des déchets radioactifs géologiquement séquestrés. Les processus dynamiques de différents degrés de complexité sont de plus en plus appliqués dans les études scientifiques des processus naturels se produisant dans ces systèmes complexes. Dans ce travail de recherche, nous avons construit des modèles hydrodynamiques dans deux zones géologiques différentes. D'abord dans le bassin sédimentaire de la Nouvelle-Zélande avec la présence d'hydrates de gaz. Nous étudions le soulèvement de la base de la zone de stabilité des hydrates de gaz, qui dépend des champs de pression et de température dans la zone étudiée. La distribution de la température est régie par la conduction thermique dans les sédiments et la convection thermique associée à la circulation des fluides dans les roches poreuses. Il s'est principalement concentré sur la circulation des fluides dans les failles, qui devraient induire des modifications importantes du champ de température. Le deuxième site est celui de Soultz-sous-Forêts, qui se trouve dans le Fossé du Rhin supérieur et qui est l'un des rares sites de "système géothermique amélioré" (EGS) en exploitation dans le monde. Le site de Soultz-sous-Forêts est caractérisé par une faible porosité de la matrice, la circulation naturelle ou induite des fluides se fait à travers les réseaux de fractures. La connexion au sein des réseaux de fractures est faible, associée à une faible perméabilité. L'objectif de cette étude est de comprendre l'influence des failles sur les mécanismes de circulation des fluides et de production d'eau en utilisant un simulateur de dynamique des fluides. La validation du modèle a été réalisée en comparant la température de fond de puits disponible avec les données simulées For a number of geoscience applications, understanding transport mechanisms in naturally fractured and faulted geological systems is getting great attention. Fault zone systems play a significant control on subsurface fluid flow in many geological and hydrogeological processes. Fault hydraulic properties may control the exploitation of geothermal reservoirs, the migration of petroleum hydrocarbons, and the transport of geologically sequestered radioactive waste materials. Dynamic processes of various degrees of complexity are increasingly applied in scientific studies of natural processes occurring those complex systems.In this research work, we constructed hydrodynamic models in two different geological areas. Firstly in the sedimentary basin in New Zealand with the presence of gas hydrates. We study the uplifting of the base of gas hydrates stability zone, which depends on the pressure and temperature fields in the studied area. The temperature distribution is governed by thermal conduction in the sediments and thermal convection associated with fluid flow in the porous rocks. It mainly focused on fluid circulation in faults, which were expected induce important modifications of the temperature field.Secondly, is Soultz-sous-Forêts, which locates in the Upper Rhine Graben and it is one of the world's few deep “enhanced geothermal system” (EGS) sites in operation. Soultz-sous-Forêts site is characterized by low matrix porosity, natural or induced fluid circulation occurs across the fracture networks. The connection within fracture networks is poor, associated with low permeability. The objective of this study is to understand the influence of faults on fluid circulation and water production mechanisms using a fluid dynamic simulator. Model validation was carried out by comparing the available downhole temperature with the simulated data

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Chen, Yi. "The redefined centre, periphery and margin : the long-term interaction sphere of southern China 3000-221 BC." Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:0ae8b337-7a65-427d-9a37-9be7f4d17f9c.

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This thesis investigates southern China as a part of dynamic and extensive interregional networks from the third to the first millennium BC and explores the changing roles of different southern regions within the interregional relationships. This was an important transitional period for southern China as it was the time when several prominent and farreaching innovations of technologies and material culture were made or adopted in the area. Four key sets of materials – rice, bronze, ceramics and jade – are examined with a World-system perspective to reveal interregional contacts in different directions and of different nature between southern China and a number of neighbouring regions. By stressing on local responses towards different technologies and material culture in different period, an alternative narrative to that stemmed from Chinese historiography is, therefore, suggested. Instead of being a passive and 'backward' periphery in the traditional sense, southern China presents diversification of material culture over time. Many of the mechanisms of transmission and circulation in the south are characterised by 'leaked' technologies and designs, as well as 'selective adoption' and local redevelopment of material culture.

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25

Van, Der Merwe Willem Conradie. "Basin margin failure processes during the initiation of a deepwater system : The Vischkuil Formation, Laingsburg depocentre, SW Karoo Basin, South Africa." Thesis, University of Liverpool, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511032.

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26

Men, Kun. "Long term voltage stability analysis for small disturbances." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2499.

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27

Symeou, Vasilis. "Transition from compression to strike-slip tectonic styles along the northern margin of the Levant Basin." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS003/document.

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En Méditerranée orientale, l’arc de Chypre est une frontière géologique majeure où interagissent les plaques Arabie, Afrique, Eurasie et la microplaque anatolienne. Il constitue la limite Nord du bassin du Levant (croûte continentale amincie étirée) et du bassin d’Hérodote (croûte océanique). L’arc de Chypre est directement lié à la convergence vers le Nord de la plaque Africaine sur la plaque Eurasienne depuis la fin du Crétacé. Dans la région Egéenne, l’indentation de la plaque Arabique sur la partie orientale de la plaque Anatolienne d’une part, et l’effet « roll back » du plan de subduction africain dans la partie occidentale de la plaque Anatolienne d’autre part, ont pour conséquence l’expulsion de l’Anatolie depuis la fin du Miocène à aujourd’hui, ce qui se traduit par un décrochement le long de l’arc de Chypre, se prolongeant sur l’île de Chypre. Plusieurs questions scientifiques concernant le cadre géologique de la région ont été étudiées au cours de ce projet. Comment la déformation est-elle intégrée dans le système de l'Arc de Chypre ? La variation crustale de chaque domaine affecte-t-elle le style de déformation ? Comment cette déformation est-elle enregistrée dans les sédiments de l’île de Chypre ? Comment ces déformations (Onshore / Offshore) peuvent être connectées au contexte géodynamique régional ? Afin de répondre à ces questions scientifiques, des données sismiques de réflexion 2D ont été utilisées, et ont permis d’imager les structures principales et leur évolution spatiale dans les parties Sud et Orientale de Chypre. L'interprétation de ces données conduit à l'identification de neuf unités tectono-sédimentaires dans trois différents domaines de la croûte crustale au sud du système de l'Arc chypriote: (1) le bassin du Levant (croûte continentale amincie), (2) le micro-continent d'Eratosthène (croûte continentale) et (3) le bassin d'Hérodote (croûte océanique). Dans ces domaines, de nombreuses structures tectoniques ont été documentées et analysées afin de comprendre le mécanisme et le timing de la déformation. À la limite nord du domaine du bassin du Levant, des accidents majeures chevauchants vers le Sud ont été documentés dans le bassin de Chypre, commençant au début du Miocène et enregistrés par les failles de Larnaca et de Margat. La faille Latakia n’a quant à elle enregistré aucune activité pendant cette période. L'apogée de la déformation s'est produite du Miocène moyen jusqu’à la fin du Miocene, l'activité de la faille de Latakia indiquant la propagation vers le Sud du front de déformation. Cette migration vers le sud a été documentée à partir du développement de bassins flexuraux et des chevauchements stratigraphiques dans le bassin de Chypre. Les pulses tectoniques successifs depuis la fin du Miocène jusqu’à aujourd’hui, sont indiquées par les discordances angulaires et les bassins piggy back. Pendant la période Plio-Pléistocène, l’expulsion vers l'ouest de la microplaque anatolienne a entraîné la réactivation des structures existantes. L'évolution de la déformation le long de la limite de la plaque est identifiée à partir de la création de structures en fleur positives révélant des mouvements transpressifs le long des failles Larnaca et Latakia (domaines orientaux). Le domaine central comprend le mont sous-marin d'Eratosthène qui se caractérise comme une plate-forme carbonatée mésozoïque recouverte d'une mince séquence sédimentaire allant des dépôts Messinien aux dépôts Pléistocène The Cyprus Arc system is major plate boundary of the Eastern Mediterranean where different plates interact, namely Arabia, Africa, Eurasia, as well as the Anatolian micro-plate. It constitutes the northern boundary of the Levant Basin (of thin stretched continental crust) and the Herodotus Basin (of oceanic crust). The Cyprus Arc is directly linked with the northward convergence of the African continental plate with respect to the Eurasian continental plate since Late Cretaceous time. The indentation of the Arabian plate and the slab pull effect of the African plate roll back in the Aegean region on the eastern and western part of the Anatolian plate respectively, leads to the westward escape of Anatolia from Late Miocene to Recent, which results in a strike-slip component along the Cyprus Arc system and onshore Cyprus. Several scientific questions with regard to the geological setting of the region were investigated during this project. How is the deformation accommodated at the Cyprus Arc system? Is this deformation style affected by the variation of the crustal nature at each domain? How is this deformation recorded on the sedimentary pile onshore Cyprus? How does the onshore and offshore deformation connect within the geodynamic context of the region? In order to answer these scientific questions, 2D reflection seismic data were utilized, that image the main plate structures and their lateral evolution south and east of Cyprus. Interpretation of these data lead to the identification of nine tectono-sedimentary packages in three different crustal domains south of the Cyprus Arc system: (1) The Levant Basin (attenuated continental crust), (2) The Eratosthenes micro-continent (continental crust) and (3) The Herodotus Basin (oceanic crust). Within these domains, numerous tectonic structures were documented and analysed in order to understand the mechanism and timing of deformation. At the northern boundary of the Levant Basin domain, thrust faults verging towards the south were documented in the Cyprus Basin with the thrust movement commencing in Early Miocene time as indicated by on the Larnaca and Margat Ridges. On the Latakia Ridge no activity was identified during this time interval. The acme of deformation occurred in Middle to Late Miocene time, with the activity of the Latakia Ridge indicating the forward propagation of the deformation front towards the south. This southward migration was documented from the development of flexural basins and from stratigraphic onlaps in the Cyprus Basin. Successive tectonic pulses through the Late Miocene until Recent times, are indicated from the angular unconformities and the piggy back basins. In Plio-Pleistocene time, the westward escape of the Anatolian micro-plate resulted in the reactivation of existing structures. The evolution of deformation along the plate boundary is identified from the creation of positive flower structures revealing transpressive movements along the Larnaca and Latakia Ridges (eastern domains). The central domain includes the Eratosthenes Seamount which is characterized as a Mesozoic carbonate platform covered by a thin sequence of sediments ranging from Miocene-Messinian to Pliocene-Pleistocene depositions

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Swofford, Mark. "RURAL HOSPITAL SYSTEM AFFILIATIONS AND THEIR EFFECTS ON HOSPITAL ECONOMIC PERFORMANCE, 2004-2008." VCU Scholars Compass, 2011. https://scholarscompass.vcu.edu/etd/2512.

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The formation of multi-hospital systems represents one of the largest structural changes in the hospital industry. As of 2008, system affiliated hospitals outnumbered stand alone hospitals 2511 to 2167 and the percentage of system affiliated rural hospitals has increased dramatically from 24.8% in 1983 to 42.2% in 2008 (based on AHA data for non-federal acute care general hospitals). The effects of system membership on hospital performance have been of great interest to health care researchers, but the majority of research on multi-hospital systems has either focused exclusively on urban facilities or pooled urban and rural facilities in the same sample, and thus failed to allow for potential differences in membership effects between urban and rural hospitals. The result is that the effect of system membership on rural hospital performance has remained largely unexplored, creating a gap in the body of health services research. The objectives of this study are both theoretical and empirical. Theoretically, this study is intended to be a deliberate empirical application of contingency theory, which is the one major organizational theory that seeks to explain variations in organizational performance as its fundamental purpose. Empirically, this study seeks to explore the relationship between rural hospital system membership and rural hospital performance, taking into account the environment of the rural hospital and the structure of the multi-hospital system to which it belongs. The study sample consists of 1010 non-federal, short-term, acute care general rural hospitals with consistent system membership and critical access hospital (CAH) status from 2004 to 2008. Hospital economic performance is represented by the dependent variables of hospital total margin and a productive efficiency score calculated using Data Envelopment Analysis (DEA). Four contingent pairs containing measures for environmental munificence, system membership, the presence of local system partners, the presence of hierarchical system partners, and CAH status, were used to measure a hospital’s fit between environment and structure. Regression analysis was used to determine the relationship between hospital performance and the fit between a hospital’s environment and its organizational/system structure. Results of the analysis indicate that hospitals with a better fit have significantly higher total margins, but results for productive efficiency were largely insignificant.

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29

Rubasha, Herbert. "Appreciating diversity : is the doctrine of margin of appreciation as applied in the European Court of Human Rights relevant in the African human rights system?" Diss., University of Pretoria, 2006. http://hdl.handle.net/2263/1228.

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"The purpose of this study is to interrogate the doctrine of margin of appreciation as applied in the European Court of Human Rights and establish amenable lessos to the African human rights system. As such, the author will be able to draw appropriate and informed recommendations on the prospects of the doctrine in African context. In other words, the study proceeds from the approach that 'diversity' alone is not enough to guarantee application of margin of appreciation. Rather, a variety of factors come into consideration while weighing whether margin of appreciation should be granted to states. Indeed, such benchmarks will inform the discourse of this study, while at the same time acknowledging that a comparative study between European and African systems cannot be possible. The premise for disqualifying a comparison assumes that margin of appreciation presupposes a democratic society. Thus, while the member states of the ECHR have attained high levels of human rights records, some of their counterparts in Africa are still marred by embarrassing human rights records." -- Preamble. "Chapter one introduces the study and the context in which it is set. It highlights the basis and structure of the study. Chapter two makes reference to the connotation, origin and development of the doctrine of margin of appreciation. It discusses also contours and varying degrees of the doctrine's application with particular regard to respect of the rule of law. In addition, difficulties linked to the doctrine are highlighted. Chapter three highlights policy grounds underlying margin of appreciation in the European Court of Human Rights. It starts from most decisive policy grounds and moves to weaker ones. Chapter four examines the legal basis for application of the doctrine of margin of appreciation under the African Charter. It further notes the attitude of African states through their submissions claiming margin. The Prince case as the first of its kind to invoke margin of appreciation is discussed. Chapter five attempts to identify the defensibility and indefensibility of the doctrine in [the] African human rights system. Chapter six consists of a summary of the presentation and the conclusions drawn from the entire study." -- Introduction. Prepared under the supervision of Prof. Gilles Cistac at the Faculty of Law, Universidade Eduardo Mondlane, Maputo, Mocambique Thesis (LLM (Human Rights and Democratisation in Africa)) -- University of Pretoria, 2006. http://www.chr.up.ac.za/academic_pro/llm1/dissertations.html Centre for Human Rights LLM

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30

Symeou, Vasilis. "Transition from compression to strike-slip tectonic styles along the northern margin of the Levant Basin." Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS003.

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En Méditerranée orientale, l’arc de Chypre est une frontière géologique majeure où interagissent les plaques Arabie, Afrique, Eurasie et la microplaque anatolienne. Il constitue la limite Nord du bassin du Levant (croûte continentale amincie étirée) et du bassin d’Hérodote (croûte océanique). L’arc de Chypre est directement lié à la convergence vers le Nord de la plaque Africaine sur la plaque Eurasienne depuis la fin du Crétacé. Dans la région Egéenne, l’indentation de la plaque Arabique sur la partie orientale de la plaque Anatolienne d’une part, et l’effet « roll back » du plan de subduction africain dans la partie occidentale de la plaque Anatolienne d’autre part, ont pour conséquence l’expulsion de l’Anatolie depuis la fin du Miocène à aujourd’hui, ce qui se traduit par un décrochement le long de l’arc de Chypre, se prolongeant sur l’île de Chypre. Plusieurs questions scientifiques concernant le cadre géologique de la région ont été étudiées au cours de ce projet. Comment la déformation est-elle intégrée dans le système de l'Arc de Chypre ? La variation crustale de chaque domaine affecte-t-elle le style de déformation ? Comment cette déformation est-elle enregistrée dans les sédiments de l’île de Chypre ? Comment ces déformations (Onshore / Offshore) peuvent être connectées au contexte géodynamique régional ? Afin de répondre à ces questions scientifiques, des données sismiques de réflexion 2D ont été utilisées, et ont permis d’imager les structures principales et leur évolution spatiale dans les parties Sud et Orientale de Chypre. L'interprétation de ces données conduit à l'identification de neuf unités tectono-sédimentaires dans trois différents domaines de la croûte crustale au sud du système de l'Arc chypriote: (1) le bassin du Levant (croûte continentale amincie), (2) le micro-continent d'Eratosthène (croûte continentale) et (3) le bassin d'Hérodote (croûte océanique). Dans ces domaines, de nombreuses structures tectoniques ont été documentées et analysées afin de comprendre le mécanisme et le timing de la déformation. À la limite nord du domaine du bassin du Levant, des accidents majeures chevauchants vers le Sud ont été documentés dans le bassin de Chypre, commençant au début du Miocène et enregistrés par les failles de Larnaca et de Margat. La faille Latakia n’a quant à elle enregistré aucune activité pendant cette période. L'apogée de la déformation s'est produite du Miocène moyen jusqu’à la fin du Miocene, l'activité de la faille de Latakia indiquant la propagation vers le Sud du front de déformation. Cette migration vers le sud a été documentée à partir du développement de bassins flexuraux et des chevauchements stratigraphiques dans le bassin de Chypre. Les pulses tectoniques successifs depuis la fin du Miocène jusqu’à aujourd’hui, sont indiquées par les discordances angulaires et les bassins piggy back. Pendant la période Plio-Pléistocène, l’expulsion vers l'ouest de la microplaque anatolienne a entraîné la réactivation des structures existantes. L'évolution de la déformation le long de la limite de la plaque est identifiée à partir de la création de structures en fleur positives révélant des mouvements transpressifs le long des failles Larnaca et Latakia (domaines orientaux). Le domaine central comprend le mont sous-marin d'Eratosthène qui se caractérise comme une plate-forme carbonatée mésozoïque recouverte d'une mince séquence sédimentaire allant des dépôts Messinien aux dépôts Pléistocène The Cyprus Arc system is major plate boundary of the Eastern Mediterranean where different plates interact, namely Arabia, Africa, Eurasia, as well as the Anatolian micro-plate. It constitutes the northern boundary of the Levant Basin (of thin stretched continental crust) and the Herodotus Basin (of oceanic crust). The Cyprus Arc is directly linked with the northward convergence of the African continental plate with respect to the Eurasian continental plate since Late Cretaceous time. The indentation of the Arabian plate and the slab pull effect of the African plate roll back in the Aegean region on the eastern and western part of the Anatolian plate respectively, leads to the westward escape of Anatolia from Late Miocene to Recent, which results in a strike-slip component along the Cyprus Arc system and onshore Cyprus. Several scientific questions with regard to the geological setting of the region were investigated during this project. How is the deformation accommodated at the Cyprus Arc system? Is this deformation style affected by the variation of the crustal nature at each domain? How is this deformation recorded on the sedimentary pile onshore Cyprus? How does the onshore and offshore deformation connect within the geodynamic context of the region? In order to answer these scientific questions, 2D reflection seismic data were utilized, that image the main plate structures and their lateral evolution south and east of Cyprus. Interpretation of these data lead to the identification of nine tectono-sedimentary packages in three different crustal domains south of the Cyprus Arc system: (1) The Levant Basin (attenuated continental crust), (2) The Eratosthenes micro-continent (continental crust) and (3) The Herodotus Basin (oceanic crust). Within these domains, numerous tectonic structures were documented and analysed in order to understand the mechanism and timing of deformation. At the northern boundary of the Levant Basin domain, thrust faults verging towards the south were documented in the Cyprus Basin with the thrust movement commencing in Early Miocene time as indicated by on the Larnaca and Margat Ridges. On the Latakia Ridge no activity was identified during this time interval. The acme of deformation occurred in Middle to Late Miocene time, with the activity of the Latakia Ridge indicating the forward propagation of the deformation front towards the south. This southward migration was documented from the development of flexural basins and from stratigraphic onlaps in the Cyprus Basin. Successive tectonic pulses through the Late Miocene until Recent times, are indicated from the angular unconformities and the piggy back basins. In Plio-Pleistocene time, the westward escape of the Anatolian micro-plate resulted in the reactivation of existing structures. The evolution of deformation along the plate boundary is identified from the creation of positive flower structures revealing transpressive movements along the Larnaca and Latakia Ridges (eastern domains). The central domain includes the Eratosthenes Seamount which is characterized as a Mesozoic carbonate platform covered by a thin sequence of sediments ranging from Miocene-Messinian to Pliocene-Pleistocene depositions

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31

Pontes, Diogo Alberto Lourenço. "Inventariação e análise dos autos de delimitação do Domínio Público Marítimo na área de intervenção da Polis Litoral - Ria de Aveiro." Master's thesis, ISA/UTL, 2012. http://hdl.handle.net/10400.5/5323.

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Mestrado em Engenharia do Ambiente - Instituto Superior de Agronomia The procedure of delimitation of the Public Domain Water (DPH) determines the limits of the Maritime Public Domain (DPM) in the confrontation with another ground natures. This procedure is reflected by the publication of the Delimitation Act. According to the Law of Ownership of Water Resources, the Portuguese Water Institute (INAG) has the jurisdiction on the inventory of the Delimitation Act. In this context, the aims of this work are to inventor, systematize and review of published Delimitation Act of DPM in the area of Polis Litoral - Ria de Aveiro. In order to meet the proposed objectives, was developed a methodology of analysis that contemplates beyond the analysis of the delimitation Act, a comparative analysis of the published limits of DPM with limits estimated by applying the criteria (approved by INAG) for demarcation of the seabed and margin for the effect of identification of the jurisdiction area of the Portuguese Water Authority. The errors/anomalies resultant from the application of the methodology has two distinct origins: Act errors and comparison anomalies. To be statistically analyzed they were divided into classes in order to test the interaction between the errors classes. It was concluded that interactions exist between the errors classes.

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Rossetto, Anubis Graciela de Moraes. "Impact FD : an unreliable failure detector based on process relevance and confidence in the system." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/150037.

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Detectores de falhas não confiáveis tradicionais são oráculos disponíveis localmente para processos deumsistema distribuído que fornecem uma lista de processos suspeitos de terem falhado. Este trabalho propõe um novo e flexível detector de falhas não confiável, chamado Impact FD, que fornece como saída um valor trust level que é o grau de confiança no sistema. Ao expressar a relevância de cada processo por um valor de fator de impacto, bem como por uma margem de falhas aceitáveis do sistema, o Impact FD permite ao usuário ajustar a configuração do detector de falhas de acordo com os requisitos da aplicação: em certos cenários, o defeito de umprocesso de baixo impacto ou redundante não compromete a confiança no sistema, enquanto o defeito de um processo de alto fator de impacto pode afetá-la seriamente. Assim, pode ser adotada uma estragégia de monitoramento com maior ou menor rigor. Em particular, definimos algumas propriedades de flexibilidade que caracterizam a capacidade do Impact FD para tolerar uma certa margem de falhas ou falsas suspeitas, ou seja, a sua capacidade de fornecer diferentes conjuntos de respostas que levam o sistema a estados confiáveis. O Impact FD é adequado para sistemas que apresentam redundância de nodos, heterogeneidade de nodos, recurso de agrupamento e permite uma margem de falhas que não degrada a confiança no sistema. Nós também mostramos que algumas classes do Impact FD são equivalentes a § e , que são detectores de falhas fundamentais para contornar a impossibilidade de resolver o problema do consenso em sistemas de transmissão de mensagens assíncronas na presença de falhas. Adicionalmente, com base em pressupostos de sincronia e nas abordagens baseada em tempo e padrão de mensagem, apresentamos três algoritmos que implementam o Impact FD. Os resultados da avaliação de desempenho usando traces reais do PlanetLab confirmam o grau de aplicabilidade flexível do nosso detector de falhas e, devido à margem aceitável de falhas, o número de falsas respostas ou suspeitas pode ser tolerado quando comparado a tradicionais detectores de falhas não confiáveis. Traditional unreliable failure detectors are per process oracles that provide a list of processes suspected of having failed. This work proposes a new and flexible unreliable failure detector (FD), denoted the Impact FD, that outputs a trust level value which is the degree of confidence in the system. By expressing the relevance of each process by an impact factor value as well as a margin of acceptable failures of the system, the Impact FD enables the user to tune the failure detection configuration in accordance with the requirements of the application: in some scenarios, the failure of low impact or redundant processes does not jeopardize the confidence in the system, while the crash of a high impact process may seriously affect it. Either a softer or stricter monitoring strategy can be adopted. In particular, we define some flexibility properties that characterize the capacity of the Impact FD to tolerate a certain margin of failures or false suspicions, i.e., its capacity of providing different sets of responses that lead the system to trusted states. The Impact FD is suitable for systems that present node redundancy, heterogeneity of nodes, clustering feature, and allow a margin of failures which does not degrade the confidence in the system. We also show that some classes of the Impact FD are equivalent to and § which are fundamental FDs to circumvent the impossibility of solving the consensus problem in asynchronous message-passing systems in presence of failures. Additionally, based on different synchrony assumptions and message-pattern or timer-based approaches, we present three algorithms which implement the Impact FD. Performance evaluation results using real PlanetLab traces confirmthe degree of flexible applicability of our failure detector and, due to the accepted margin of failures, that false responses or suspicions may be tolerated when compared to traditional unreliable failure detectors.

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33

Grobler, Johannes Petrus. "Design and implementation of a high resolution soft real-time timer." Diss., Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-08282007-095022.

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34

Mountjoy, Joshu Joseph Byron. "Development of submarine canyon systems on active margins: Hikurangi Margin, New Zealand." Thesis, University of Canterbury. Geological Sciences, 2009. http://hdl.handle.net/10092/3107.

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The development and activity of submarine canyons on continental margins is strongly influenced by temporal and spatial changes in sediment distribution associated with orbitally-forced sea-level cyclicity. On active margins, canyons are also strongly influenced by tectonic processes such as faulting, uplift and earthquakes. Within this framework the role of mass-wasting processes, including sediment failures, bedrock landslides and sediment gravity flows, are to: 1) transport material across the slope; 2) act as intra-slope sediment sources; and 3) shape seafloor morphology. In this project the seafloor-landscape signatures of tectonic and geomorphic processes are analysed to interpret the development of submarine canyon morphology on active margins. Datasets include high-resolution bathymetry data (Simrad EM300), multichannel seismic reflection data (MCS), high-resolution 3.5 kHz seismic reflection data, sediment cores, and dated seafloor samples. High-resolution bathymetric grids are analysed using techniques developed for terrain-roughness analysis in terrestrial landscapes to objectively map and interpret features related to seafloor mass-wasting processes. The Hikurangi subduction margin of New Zealand provides world-class examples of the control of tectonic and sedimentary processes on margin development, hosting multiple examples of deeply-incised canyon systems across a range of scales. Two main study sites, in Poverty Bay and Cook Strait, provide examples of canyon formation. From these examples conceptual and representative models are developed for the spatial and temporal relationships between active tectonic structures, geology, sediment supply, slope- and shelf-incised canyons, slope gully systems, and bedrock mass failures. The Poverty Bay site occurs on the subduction-dominated northern Hikurangi Margin, where the ~3000 km² Poverty re-entrant hosts the large Poverty Canyon system, the only shelf-break-to-subduction-trough canyon on the northern margin. The geomorphic development of the re-entrant is affected by gully development on the upper slope, and multi-cubic-kilometre-scale submarine landslides. From this site the study focuses on the initiation and development of upper-slope gullies and the role of deep-seated slope failure in upper-slope evolution. The Cook Strait site occurs on the southern Hikurangi Margin in the subduction-to-strike-slip transition zone. The 1800 km² Cook Strait Canyon incises almost 50 km into the continental shelf, with a multi-branching canyon head converging to a deeply slope-incised meandering main channel fed by multiple contributing slope canyons. Other medium-sized canyons are incised into the adjacent continental slope. Fluvial sediment supply to the coast is relatively low on the southern margin, but Cook Strait is subject to large diurnal tidal currents that mobilise sediment through the main strait area. Prior to the morphostructural analysis of the Cook Strait and Poverty study sites a revision of the tectonic structure was undertaken. In Cook Strait a revision of the available fault maps was undertaken as part of a wider, related tectonic study of the central New Zealand region. In Poverty Bay very limited prior information was available, and as part of this study the structure and stratigraphy of the entire shelf and upper slope has been interpreted. On active tectonic margins submarine canyons respond to tectonics at: 1) margin-setting scales relating to their ability to become shelf incised; 2) regional scales relating to canyon-incision response to base-level perturbations; and 3) local scales relating to propagating structures affecting canyon location and geometry. Interpretation of the spatial distribution of fluid vent sites, gully development and landslide scars leads to the conclusion that seepage-driven failure is not a primary control on the widespread instances of gully formation and landslide erosion affecting structurally-generated relief across the margin. Rather, the erosion of tectonic ridges is dominated by tectonics by: slope oversteepening; weakening of the rockmass in fault-damage zones; and triggering of slope failure by earthquake-generated cyclic loading. Deep-seated mass failures affect numerous aspects of submarine landscapes and play a major role in the enlargement of canyon systems. They enable the development of slope gully systems and represent a major intra-slope sediment source. Quantitative morphometric analysis together with MCS data indicate that landslides may evolve to be active complexes where landslide debris is remobilized repeatedly, analogous to terrestrial-earthflow processes. This process has not previously been documented on submarine slopes. A model is presented for the evolution of active margin canyons that contrasts highstand and lowstand canyon activity in terms of channel incision, sedimentary processes and slope-erosion processes. During sea-level highstand intervals, canyons become decoupled from their terrestrial/coastal sediment-supply source areas, while during sea-level lowstand intervals, canyons are coupled to fluvial and littoral sediment-supply sources, and top-down (i.e. shelf-to-lower-slope) sediment transport and channel incision is active. Canyon-head areas are incision dominated during the lowstand while mid to lower canyon reaches experience both a transient increase in sediment in storage and canyon-fill degradation and incision into bedrock. Tectonics influences the canyon landscape through both uplift-controlled perturbations to canyon base-levels and earthquake-triggering of mass movement. Following sea-level rise the sediment supply to canyon heads will be switched off at a certain threshold sea level. From this point canyon heads become aggradational. Mid to lower canyon reaches continue to incise due to continuing tectonic uplift and earthquake-triggered slope instability. Knickpoints are propagated up channel and excavate canyon and sub-canyon channels from the bottom up. Thus, while top-down infilling of non-coupled canyons occurs during sea-level highstands, the lower reaches of active margin canyons continue to incise due the influence of tectonic processes.

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Rosa, Arlei Lucas de Souza. "Avaliação do reforço das condições da segurança de tensão utilizando a análise de sensibilidade." Universidade Federal de Juiz de Fora (UFJF), 2009. https://repositorio.ufjf.br/jspui/handle/ufjf/3510.

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Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-03-02T12:45:01Z No. of bitstreams: 1 arleilucasdesouzarosa.pdf: 827143 bytes, checksum: 9b9df97bf2f2804c9287dcee04958895 (MD5) Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-03-06T19:38:30Z (GMT) No. of bitstreams: 1 arleilucasdesouzarosa.pdf: 827143 bytes, checksum: 9b9df97bf2f2804c9287dcee04958895 (MD5) Made available in DSpace on 2017-03-06T19:38:30Z (GMT). No. of bitstreams: 1 arleilucasdesouzarosa.pdf: 827143 bytes, checksum: 9b9df97bf2f2804c9287dcee04958895 (MD5) Previous issue date: 2009-05-27 CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Durante décadas, problemas relacionados à estabilidade de tensão ou, segurança de tensão, têm despertada a atenção crescente de pesquisadores do setor elétrico. O crescimento da economia e o aumento do consumo de energia elétrica, aliados à falta de investimentos nos setores de geração e transmissão, têm levado o sistema elétrico de potência a operar muito próximo de seus limites. Desta forma, a habilidade do sistema em manter um nível operacional satisfatório, após a ocorrência de alguma contingência, pode ficar comprometida. Este trabalho avalia a segurança de tensão através de um método simples, eficiente e rápido computacionalmente, além de propor ações de reforço para melhorar a margem de carregamento do sistema elétrico. A análise da rede é função dos caminhos de transmissão de potência ativa e um modelo matemático muito simples é utilizado. Quanto às ações de reforço, a análise de sensibilidade fornece as barras mais adequadas ao redespacho de potência ativa e reativa. Um processo iterativo é estabelecido com o intuito de recomendar ações de controle e fornecer condições de segurança de tensão menos severas. Os resultados apresentados para um sistema real de 34 barras demonstram a eficácia da metodologia desenvolvida. Voltage stability or voltage security analysis has motivated an expressive attention of power systems researchers. The economy growth and the increased electric energy consumption, allied to the lack of investments in generation and transmission areas, have led electrical power systems to operate very close to their limits. Therefore, they cannot be able to operate in a secure way after some contingencies. In this work, a simple and fast method evaluates voltage security and proposes conditions to improve the loading margin. System analysis is carried out in terms of active power transmission path. Sensitivity analysis provides the most adequate buses to active and reactive power redispatch. A sequential iterative methodology to reinforce system conditions is presented. The results for a real 34-bus system demonstrate the efficiency of proposed methodology.

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Červíček, Karel. "Algoritmické obchodování na burze s využitím genetických algoritmů." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2019. http://www.nusl.cz/ntk/nusl-403187.

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p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Helvetica} Automatization is higly used in stock traiding. The thesis try to exploid optimalization principles and machine learning. Developed and tested stock traiding system proces financial time series and generate optimal strategy

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Silva, Tatiana Rondon Viegas da. "Modelo matemático para a melhoria da estabilidade transitória de sistemas elétricos de potência baseado na mudança estrutural do sistema de transmissão /." Ilha Solteira, 2019. http://hdl.handle.net/11449/181427.

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Orientador: Carlos Roberto Minussi Resumo: Apresenta-se um modelo matemático, baseado na análise de sensibilidade, para a realização de controle de segurança dinâmica para a melhoria da estabilidade transitória de sistemas elétricos de potência. O controle de segurança dinâmica implementado consiste na alteração da impe-dância do sistema elétrico pela retirada/inclusão de linhas de transmissão. A proposta consiste em determinar um modelo de sensibilidade da margem de segurança do sistema em relação à admitância (impedância) do elemento considerado. Deste modo, pode-se estimar o impacto que as alterações no sistema de transmissão podem causar sobre a estabilidade transitória do sistema. Com as devidas adaptações, os resultados aqui apresentados podem ser estendidos para o caso do uso de dispositivos FACTS. A análise da estabilidade é realizada, via uso do conceito de sensibilidade da margem de segurança do sistema, que é determinada pelo Méto-do Direto de Lyapunov, por meio da função de energia total do sistema. Trata-se de um resul-tado que visa dar maior suporte ferramental aos planejadores e aos operadores dos sistemas de energia elétrica. Visando ilustrar os resultados auferidos com a aplicação do modelo proposto, são apresentados os resultados via simulações considerando-se dois sistemas de energia elétri-ca (sistema de 9 barras / sistema clássico Anderson & Fouad, e uma versão do sistema sul bra-sileiro). Abstract: This work presents a mathematical model based on sensitivity analysis for the implementation of Security Dynamic Control for improvement of transient stability of electric power systems. The Security Dynamic Control performed corresponds to system impedance change by out-put/input of transmission lines (TL’s). The propose aims to determine a sensitivity model for the security margin of the system in relation to the impedance (susceptance) of the considered element. Thus, it is possible estimate the influence of TL’s on transient stability. Considering adaptations and some simplifications, the results obtained with this proposal can be used for FACTS devices. The stability analysis is achieved using the Security Margin concept deter-mined by the direct Lyapunov (energy) method; it is a supporting tool to the planners and op-erators of electric power systems. In order to illustrate the results obtained with the application of the proposed model, the simulation results are presented considering two electric power systems (9-bus system / Anderson & Fouad classic system, and one version of the South Bra-zilian system). Doutor

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Gerlichová, Veronika. "Využití controllingu v podniku." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2019. http://www.nusl.cz/ntk/nusl-402048.

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The master´s thesis is focused on application of Management Control System in a company especially on operative planning and devations analysis. The first part of the master´s thesis is theoretical with basic terms and used continualy in the analytical part. In analytical part the company ABC s.r.o. will be described and analyzed its currently used planning method for 2018. Then will be used deviation analysis. In the proposal part i will try to propose corrective actions, to improve the current situation in the form of a plan using the cover margin contribution.

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Biscara, Laurie. "Le système turbiditique de l’Ogooué (Gabon, Marge Ouest Africaine) : Évolution Fini- Holocène de la morphologie et de la dynamique sédimentaire." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14368/document.

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Ce travail présente une analyse de la dynamique sédimentaire du système turbiditique actuel de l’Ogooué (Golfe de Guinée), secteur encore très peu exploré à l’heure actuelle. Il se base sur l’interprétation de données géo-acoustiques (sondeur multifaisceaux et sismique chirp), sédimentologiques (carottes küllenberg et interface) et courantométriques issues de campagnes océanographiques réalisées par le SHOM. L’analyse morpho-bathymétrique détaillée a révélé la diversité des structures morphologiques le long de la marge. Ces observations, associées aux données sédimentaires et courantométriques ont permis de préciser les différents processus de dépôt. La configuration du plateau continental, dont la largeur se réduit fortement vers le Nord va entraîner une variabilité des transferts sédimentaires en profondeur le long du système turbiditique de l’Ogooué. La très faible extension du plateau continental à l’extrémité de l’île Mandji et l’action de la dérive littorale favorisent une sédimentation gravitaire active sous la forme d’écoulements turbiditiques dans le canyon du Cap Lopez ou de glissements sous-marins. Grâce à la comparaison de données bathymétriques à différentes échelles de temps, il a été possible de documenter à très haute résolution les mécanismes d’initiation et de développement d’instabilités ainsi que les processus sédimentaires à l’origine du développement des méandres. En plus des apports détritiques, les écoulements gravitaires initiés dans ce secteur vont également transporter de grandes quantités de matière organique This work presents an analysis of the sedimentary dynamic in the Ogooué turbidite system (Gulf of Guinea), previously poorly studied. It is based upon the interpretation of geo-acoustic (multibeam bathymetry and imagery, seismic chirp), sedimentological (Küllenberg and interface cores) and current-meter data recovered during oceanographic cruises conducted by the SHOM. The detailed morpho-bathymetric analysis reveals the diversity of morphological structures along the margin. These observations, combined with current meter and sedimentological data allowed us to determine various depositional processes. The decreasing width of the continental shelf toward the North involves a variability of sediment transfer along the Ogooué turbidite system. The very small extension of the continental shelf at the extremity of the Mandji Island and the action of longshore drift promote active gravitary sedimentation dominated by turbiditic flows in the Cap Lopez canyon or submarine slides.By comparing bathymetric data at different time scales, we document the mechanisms responsible for the initiation and development of instabilities and the sedimentary processes related to meander growth. In addition to detrital fraction, the gravity flows initiated in this area also carry large amounts of organic matter

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Coste, Marianne. "Les processus sédimentaires, depuis la pente continentale jusqu'au bassin, en contexte de tectonique active : analyse comparée entre la Marge Calabro-Ionienne et la Marge Ligure durant les derniers 5 Ma." Phd thesis, Université Nice Sophia Antipolis, 2014. http://tel.archives-ouvertes.fr/tel-01062293.

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Les marges continentales, passives ou actives, sont la principale voie de transfert sédimentaire entre le plateau continental et le bassin océanique profond et les plaines abyssales. Les pentes continentales sont le siège de processus d'érosion/dépôt sous le contrôle de transfert de flux particulaires continentaux chenalisés par des structures érosives, telles que les canyons sous‐marins, puis redistribues à l'ensemble de la marge. Les canyons érodent fortement les pentes continentales et contribuent à l'évolution de leur morphologie au cours du temps. On retrouve cependant des canyons sous‐marins qui ne sont pas en relation avec la présence d'un réseau fluviatile. De ce fait, la formation et l'évolution des canyons sous‐marins sont encore peu comprises. Ce travail de thèse s'intéresse aux processus de formation et d'évolution de six canyons sous-marins sur la Marge Ouest du Bassin Ligure et à dix systèmes de canyons sur la Marge Calabro-Ionienne. Le but de cette étude est de contraindre les principales caractéristiques morphométriques (longueur, largeur, profondeur, inclinaison, sinuosité), morphologique (éléments architecturaux, configuration) des canyons, de caractériser leur évolution amont‐aval et d'analyser leur structure interne, afin de mieux comprendre l'origine des canyons sous‐marins, leurs mécanismes de construction et leur évolution au cours du temps en relation avec le contexte géologique régional et leurs potentiels bassins versants subaérien. Pour cela, une approche basée sur une analyse morpho-bathymétrique et géophysiques a été mise en œuvre à partir de relevés bathymétriques complets des marges, de profils de sismiques, de Chirp et de SAR.

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Koubek, Ondřej. "Využití controllingu pro porovnání plánované a skutečné výkonnosti podniku a budoucí plánování." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2018. http://www.nusl.cz/ntk/nusl-377998.

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The master's thesis deals with application of Management Control System methods, described in theoretical part of the thesis. In analytical part, those methods are used for comparison of planned performance of individual trucks in the transport company with real performance of those trucks in year 2017. Detected deviations from the plan are further analysed, in order to identify their sources and to formulate corrective measures to eliminate them. This knowledge is put to use in the proposal part, in order to create plan for year 2018, which takes into account established facts and corrective measures from previous year. Finally, part of the plan for year 2018 is compared with real data collected by the company in that period, in order to assess the plan’s accuracy, identify deviations from the plan and their sources.

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42

Кунченко, Тетяна Юріївна. "Параметрична оптимізація умовно стійких електромеханічних систем методом діаграм якості керування". Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/21345.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.09.03 – електротехнічні комплекси та системи. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2016. Дисертація присвячена визначенню і дослідженню задач оптимізації параметрів астатичних регуляторів багатократноінтегруючих систем з використанням мінімаксних критеріїв оптимізації. Виконано аналіз способів параметричної оптимізації та підвищення ефективності керування умовно стійкими багатократноінтегруючими електромеханічними системами (ЕМС) методом діаграм якості керування. Теоретично обґрунтовано існування оптимального рішення для керування такими ЕМС на основі комплексного критерія якості керування – максимуму добротності та запасу стійкості (МДС). Розроблені комп'ютерні методики побудови та аналізу діаграм якості керування (ДЯК) систем у часовій і частотних областях, на яких виділені області підвищеної добротності та запасу стійкості (ПДС). Обґрунтована інженерна методика застосування діаграм якості керування до задачі оптимізованого синтезу по критерію МДС систем з астатизмом другого і третього порядків. Виконано параметричну оптимізацію за критерієм МДС різноманітних умовно стійких ЕМС з послідовною та паралельної корекцією з урахуванням особливостей структури об'єкта керування, включаючи до її складу немінімально-фазові ланки. Розглянуті конкретні приклади підвищення ефективності керування ЕМС методом ДЯК з оптимізацією їх параметрів за мінімаксним критерієм МДС. Доказано можливість збільшення добротності систем у межах 20% і при заданій добротності збільшення запасу стійкості на 10%. The dissertation for the degree of technical sciences candidate by specialty 05.09.09 – electrical complexes and systems. – NTU "KhPI". – Kharkiv, 2016. The dissertation is devoted to researching and solving parameter optimization problems for multiple-integration system astatic regulators with minimax criterion application. Parametric optimization and control efficiency enhancement methods are analyzed as applied to conditionally stable multiple-integration electromechanical systems through control quality diagram technique. Existence of the optimal solution for conditionally stable electromechanical system control on the basis of a complex control efficiency criterion – Q-factor maximum and stability margin - is theoretically substantiated. Computer-aided techniques are worked out to develop and analyze conditionally stable system control quality diagrams in time and frequency domains in which zones of enhanced Q-factor and stability margin are marked. An engineering technique is validated for control quality diagram application to optimization synthesis of systems with astatism of the 2nd and 3rd order using the control quality diagram technique criterion. Control quality diagram technique criterion based parametric optimization of different conditionally stable electromechanical systems with series and parallel compensation is performed taking into account the control object structure features, including nonminimum phase links as its components. Specific examples of electromechanical system control enhancement via the control quality diagram technique application are considered with the system parameter optimization on the control quality diagram technique minimax criterion. Feasibility of 20% system Q-factor enhancement and 10% increase in the stability margin for a given Q is proved.

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Кунченко, Татьяна Юрьевна. "Параметрическая оптимизация условно устойчивых электромеханических систем методом диаграмм качества управления". Thesis, НТУ "ХПИ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/21350.

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Диссертация на соискание ученой степени кандидата технических наук по специальности 05.09.03 – Электротехнические комплексы и системы. – Национальный технический университет "Харьковский политехнический институт", Харьков, 2016 г. Диссертация посвящена исследованию и решению задач оптимизации параметров астатических регуляторов многократноинтегрирующих систем с использованием минимаксных критериев оптимизации. Выполнен анализ способов параметрической оптимизации и повышения эффективности управления условно устойчивыми многократно интегрирующими электромеханическими системами методом диаграмм качества управления. Теоретически обосновано существование оптимального решения для управления условно устойчивыми электромеханическими системами (ЭМС) на основании комплексного критерия качества управления – максимума добротности и запаса устойчивости (МДУ). Разработаны компьютерные методики построения и анализа ДКУ условно устойчивых систем во временной и частотной областях, на которых выделены области повышенной добротности и запаса устойчивости (ПДУ). Обоснована инженерная методика применения диаграмм качества управления к решению задач оптимизационного синтеза по критерию МДУ систем с астатизмом второго и третьего порядков. Выполнена параметрическая оптимизация по критерию МДУ различных условно устойчивых ЭМС с последовательной и параллельной коррекцией с учетом особенностей структуры объекта управления, включая в ее состав неминимально-фазовые звенья. Использование результатов работы при минимальных затратах позволяет переналадить работающие МИС ЭП, что будет способствовать повышению точности их работы, росту качества выпускаемой продукции. При разработке новых систем целесообразно расчет астатических регуляторов осуществлять на основании разработанной инженерной методики, основанной на ДКУ и линии МДУ. The dissertation for the degree of technical sciences candidate by specialty 05.09.09 – electrical complexes and systems. – NTU "KhPI". – Kharkiv, 2016. The dissertation is devoted to researching and solving parameter optimization problems for multiple-integration system astatic regulators with minimax criterion application. Parametric optimization and control efficiency enhancement methods are analyzed as applied to conditionally stable multiple-integration electromechanical systems through control quality diagram technique. Existence of the optimal solution for conditionally stable electromechanical system control on the basis of a complex control efficiency criterion – Q-factor maximum and stability margin - is theoretically substantiated. Computer-aided techniques are worked out to develop and analyze conditionally stable system control quality diagrams in time and frequency domains in which zones of enhanced Q-factor and stability margin are marked. An engineering technique is validated for control quality diagram application to optimization synthesis of systems with astatism of the 2nd and 3rd order using the control quality diagram technique criterion. Control quality diagram technique criterion based parametric optimization of different conditionally stable electromechanical systems with series and parallel compensation is performed taking into account the control object structure features, including nonminimum phase links as its components. Specific examples of electromechanical system control enhancement via the control quality diagram technique application are considered with the system parameter optimization on the control quality diagram technique minimax criterion. Feasibility of 20% system Q-factor enhancement and 10% increase in the stability margin for a given Q is proved.

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Eitzen, Fridtjof Camillo. "Mathematical Modelling of a Foil Propulsion System." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18604.

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This thesis considers a foil propulsion system on a supply vessel. In analysing the potential of a foil propulsion system, it is imperative to establish a rigid mathematical model. In that respect, modelling of the dynamic system is emphasised, and a comprehensive study is presented on the matter. The equations of motion for an oscillating foil and a vessel are derived, separately. The two systems are then combined, to form the coupled vessel-foil structure. For the vessel, a time-domain model based on Cummins' equation is proposed. Cummins' equation has proven efficient in assessing a unified seakeeping and manoeuvring problem (Fossen [2011]). In line, the vessel-foil system will be exposed to both vessel oscillatory motion due to waves and forward speed effects, i.e seakeeping and manoeuvring. Moreover, the efficiency of the foil is directly dependent on the two.Additionally, aspects of foil control is looked into. In theory, active control could maximise thrust while preventing stall, which would be ideal. The validity of simulations with active control, however, is highly dependent on the accuracy of the emph{basic} vessel-foil model. Consequently, effort has been focused on presenting a rigid mathematical foundation.

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Хазім, Ямен. "Моделі и методи управління багатонгоменклатурним складським запасом в умовах невизначеності попиту". Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/22708.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.13.03 – системи та процеси керування. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2016. Дисертаційна робота присвячена розробці моделей і методів управління багатономенклатурним запасом в багаторівневій складській системі в умовах невизначеності попиту. На основі аналізу відомих публікацій виявлені недоліки традиційно використовуваних методів вирішення задач управління запасами і сформульовані задачі дослідження. Запропоновано загальну технологію рішення багатономенклатурної задачі управління запасами. Задачу вирішено з урахуванням середніх витрат на зберігання нереалізованої частини товару і втрат від можливого дефіциту Розроблено методику розв'язання задачі управління запасами за ймовірнісним критерієм. Розглянуто методи оцінки ефективності функціонування системи масового обслуговування з немарківським вхідним потоком і немарківським обслуговуванням. Запропоновано марківську модель функціонування складської системи "оптова база - магазини" і обґрунтовано метод розрахунку розподілу ймовірностей станів. Запропоновано метод раціонального розподілу ресурсу в ієрархічній складській системі. Для випадку, коли процес функціонування системи не може бути адекватно описаний марківськими методами, задача управління вирішується з використанням імітаційної моделі. Проведено аналіз ефективності функціонування в залежності від характеристик процесу попиту і самої системи. Thesis for scientific degree of candidate of technical sciences, specialty 05.13.03 – systems and management processes. – National Technical University "Kharkiv Polytechnic Institute", Kharkov, 2016. The thesis is devoted to the development of models and multinomenclature stock management in a tiered storage system under demand uncertainty. On the basis of the known publications identified deficiencies commonly used methods for solving the inventory management problems and formulate research problems. Total technology solutions diversified inventory management tasks. The problem is solved taking into account the average cost of storing unsold part of the goods and losses due to a possible deficit procedure was developed for solving the problem of inventory management on probabilistic criteria. The methods of evaluating the performance of a queuing system with non-Markov and non-Markov input flow service. A Markov model of operation storage system "wholesale warehouse - shops" and justified method of calculating the probability distribution of states. A method for rational resource allocation in a hierarchical storage system. For the case where the system of functioning of the process can not be adequately described by the Markov method, control is achieved by using a simulation model. The analysis of the efficiency of the process, depending on the characteristics of demand and the system itself.

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Henriksen, Eirik Hexeberg. "ROV Control System for Positioning of Subsea Modules." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-27226.

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Installation of deep water Xmas trees for subsea oil production is sometimes done by lowering the tree using one wire. Xmas trees are interfacing with other equip- ment on the seafloor and will therefore need to be positioned, and oriented correct. Today aligning the Xmas tree to existing interfacing structures on the seabed dur- ing installation is done by manual control of an ROV. In this thesis it is proposed to automate this process. The benefits of doing this is to gain a faster and more precise control of the position of the tree, as well as being less prone to human errors. This will make the operation faster, safer and less expensive.This thesis is a feasibility study of this new solution for aligning the Xmas tree in the installation process. In order to investigate the feasibility of the solution a mathematical model of an ROV and a Xmas tree that is hanging in a wire has been developed. Interaction forces between these objects are then defined. A model of the environment and sensor output from the ROV is also developed.A controller algorithm has been defined that uses the position of the Xmas tree to calculate the control forces the ROV need to control the motions of the Xmas tree. This controller algorithm is a nonlinear PID-controller where the output is translated from the body-centre of the Xmas tree to the body centre of the ROV in order to use some of the existing control system in the ROV. In addition to the controller an extended kalman filter has been implemented in order to handle the sensor feedback, and a reference model has been made to generate smooth and feasible trajectories as input to the control system.The mathematical model is used to simulate the behavior of the system, when the control system is connected. The simulations shows very promising results.An experimental setup has been made in order to test the control system in real life. The experimental setup consists of a downscaled Xmas tree model, a docking frame, and a small scale ROV. This setup was used to test the control system in the Trondheim fjord using R/V Gunnerus. Due to an error in the programming the testing was not able to fully verify the simulation results. The results obtained during the test did however seem promising when this error is taken into account, and thus proof of concept was established.

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47

Хазим, Ямен. "Модели и методы управления многономенклатурным складским запасом в условиях неопределенности спроса". Thesis, НТУ "ХПИ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/22709.

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Диссертация на соискание ученой степени кандидата технических наук по специальности 05.13.03 – системы и процессы управления. – Национальный технический университет "Харьковский политехнический институт", Харьков, 2016. Диссертационная работа посвящена разработке моделей и методов управления многономенклатурным запасом в многоуровневой складской системе в условиях неопределенности спроса. На основе анализа известных публикаций выявлены недостатки традиционно используемых методов решения задач управления запасами и сформулированы задачи исследования. Предложена общая технология решения многономенклатурной задачи управления запасами. Задача решена с учетом средних затрат на хранение непроданной части товара и потерь от возможного дефицита. Задача с учетом ограничений решена методом неопределенных множителей Лагранжа. Разработана методика решения задачи управления запасами по вероятностному критерию. Для случая рэлеевского распределения спроса решение сведено к системе уравнений, решаемых численно. Предложена марковская модель функционирования складской системы "оптовая база – магазины". Введены графовая модель системы и система дифференциальных уравнений для описания поведения распределения вероятностей состояний системы. Предложен метод расчета распределения вероятностей состояний. Предложен метод рационального распределения ресурса в иерархической складской системе. Для случая рэлеевского спроса получено аналитическое решение. Рассмотрен метод решения задачи управления запасами в иерархической системе в ситуации, когда процесс функционирования системы не может быть адекватно описан марковскими методами. В этом случае задача управления решается с использованием имитационной модели. Проведен анализ эффективности функционирования в зависимости от характеристик процесса спроса и самой системы. Thesis for scientific degree of candidate of technical sciences, specialty 05.13.03 – systems and management processes. – National Technical University "Kharkiv Polytechnic Institute", Kharkov, 2016. The thesis is devoted to the development of models and multinomenclature stock management in a tiered storage system under demand uncertainty. On the basis of the known publications identified deficiencies commonly used methods for solving the inventory management problems and formulate research problems. Total technology solutions diversified inventory management tasks. The problem is solved taking into account the average cost of storing unsold part of the goods and losses due to a possible deficit procedure was developed for solving the problem of inventory management on probabilistic criteria. The methods of evaluating the performance of a queuing system with non-Markov and non-Markov input flow service. A Markov model of operation storage system "wholesale warehouse - shops" and justified method of calculating the probability distribution of states. A method for rational resource allocation in a hierarchical storage system. For the case where the system of functioning of the process can not be adequately described by the Markov method, control is achieved by using a simulation model. The analysis of the efficiency of the process, depending on the characteristics of demand and the system itself.

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48

Yavrucuk, Ilkay. "Adaptive limit margin detection and limit avoidance." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/12354.

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Nascimento, José Luiz Almeida do. "Uso de geotecnologia no monitoramento de unidades de conservação: ocupações peri urbanas na Apa margem esquerda do Rio Negro, Manaus." Universidade Federal do Amazonas, 2009. http://tede.ufam.edu.br/handle/tede/2604.

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Made available in DSpace on 2015-04-11T13:54:45Z (GMT). No. of bitstreams: 1 Disertacao Jose Luiz Nascimento.pdf: 11954689 bytes, checksum: db2a41530214bd81c32bed91fe894299 (MD5) Previous issue date: 2009-12-09 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior As técnicas de Sensoriamento Remoto e Sistemas de Informações Geográficas (SIG) têm sido utilizados de forma conjugada em estudos dos recursos terrestres, com especial atenção para o monitoramento das atividades antrópicas e seus impactos ambientais. Neste contexto, o presente trabalho foi desenvolvido tendo como objetivo mapear, através de SIG, os impactos provenientes das diferentes formas de uso do solo no interior da APA Margem Esquerda do Rio Negro Setor Tarumã-Açu/ Tarumã-Mirim. A APA, de 56.793ha, está localizada entre os paralelos 2º 41 44 e 3º 03 37 Latitude Sul e meridianos 60º 03 41 e 60º 18 27 Longitude Oeste, no município de Manaus - Estado do Amazonas. Para análise de dados de sensoriamento remoto utilizou-se imagens do satélite TM Landsat 5 (anos 1990, 1997, 2001,2005 e 2009) e QUICKBIRD (ano 2008), que subsidiaram na construção de uma base cartográfica digital. As referidas imagens foram fundamentais também na quantificação da dinâmica de desmatamento, obtida através do processo de classificação, para o período compreendido entre os anos de 1990 a 2009 e seus respectivos incrementos. O método para classificação foi a de máxima verossimilhança, focando as análises apenas nas classes de floresta, não-floresta e água, além de outras técnicas de análise da base de dados. Para estruturação da base cartográfica digital, utilizou-se o software ArcGis 9.3 e ENVI 4.4, técnicas de geoprocessamento apoiadas nos recursos disponíveis em Sistemas de Informações Geográficas, onde foram analisados aspectos relacionados ao uso e ocupação do solo e cobertura vegetal. Para construção do polígono georeferenciado da unidade foi feito interpretação do seu memorial descritivo, bem como a espacialização das coordenadas geográficas contidas no Decreto de criação e na Lei que altera posteriormente seus limites. Informações do PA Tarumã-Mirim, unidades de conservação, hidrografia, relevo, vegetação e dados coletados em campo através do georeferenciamento com uso de GPS, foram organizadas em um banco de dados geocodificado identificando e espacializando a situação fundiária da APA, bem como, alvos potenciais de degradação ambiental, áreas de preservação permanente, reservas florestais e demais atividades implantadas no espaço geográfico da APA. Tal mapeamento subsidiou a construção de um banco de dados geográficos da unidade, ferramenta fundamental no auxílio à gestão da unidade. As técnicas de Sensoriamento Remoto e Sistemas de Informações Geográficas (SIG) têm sido utilizados de forma conjugada em estudos dos recursos terrestres, com especial atenção para o monitoramento das atividades antrópicas e seus impactos ambientais. Neste contexto, o presente trabalho foi desenvolvido tendo como objetivo mapear, através de SIG, os impactos provenientes das diferentes formas de uso do solo no interior da APA Margem Esquerda do Rio Negro Setor Tarumã-Açu/ Tarumã-Mirim. A APA, de 56.793ha, está localizada entre os paralelos 2º 41 44 e 3º 03 37 Latitude Sul e meridianos 60º 03 41 e 60º 18 27 Longitude Oeste, no município de Manaus - Estado do Amazonas. Para análise de dados de sensoriamento remoto utilizou-se imagens do satélite TM Landsat 5 (anos 1990, 1997, 2001,2005 e 2009) e QUICKBIRD (ano 2008), que subsidiaram na construção de uma base cartográfica digital. As referidas imagens foram fundamentais também na quantificação da dinâmica de desmatamento, obtida através do processo de classificação, para o período compreendido entre os anos de 1990 a 2009 e seus respectivos incrementos. O método para classificação foi a de máxima verossimilhança, focando as análises apenas nas classes de floresta, não-floresta e água, além de outras técnicas de análise da base de dados. Para estruturação da base cartográfica digital, utilizou-se o software ArcGis 9.3 e ENVI 4.4, técnicas de geoprocessamento apoiadas nos recursos disponíveis em Sistemas de Informações Geográficas, onde foram analisados aspectos relacionados ao uso e ocupação do solo e cobertura vegetal. Para construção do polígono georeferenciado da unidade foi feito interpretação do seu memorial descritivo, bem como a espacialização das coordenadas geográficas contidas no Decreto de criação e na Lei que altera posteriormente seus limites. Informações do PA Tarumã-Mirim, unidades de conservação, hidrografia, relevo, vegetação e dados coletados em campo através do georeferenciamento com uso de GPS, foram organizadas em um banco de dados geocodificado identificando e espacializando a situação fundiária da APA, bem como, alvos potenciais de degradação ambiental, áreas de preservação permanente, reservas florestais e demais atividades implantadas no espaço geográfico da APA. Tal mapeamento subsidiou a construção de um banco de dados geográficos da unidade, ferramenta fundamental no auxílio à gestão da unidade.

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50

Bourget, Julien. "Les systèmes turbidiques du Golfe d'Oman et de la marge est-africaine : architecture, évolution des apports au Quaternaire terminal et impact de la distribution sédimentaire sur les propriétés géoacoustiques des fonds." Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13915/document.

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Ce travail présente une analyse des systèmes turbiditiques actuels du Golfe d’Oman et de la marge est-africaine (océan Indien occidental), auparavant méconnus. Il se base sur une base de données acoustique (bathymétrie, imagerie multifaisceaux, sismique THR et multitraces) et sédimentologique (carottes küllenberg et calypso) issues de campagnes successives réalisées par le SHOM et l’IFP. L’architecture des systèmes de dépôts profonds et les processus associés ont révélé une grande diversité selon le contexte géodynamique et physiographique des marges étudiées (marge passive, marge transformante, marge active). Les différents systèmes étudiés illustrent notamment le rôle du contexte tectonique régional sur la répartition et la morphologie des dépocentres à plusieurs échelles d’observation. L'analyse détaillée des faciès et séquences sédimentaires a permis de mettre en évidence le fonctionnement sédimentaire des différents systèmes en lien avec les conditions physiographiques et environnementales régionales (influence des crues liées à la mousson sur le transfert sédimentaire). A travers la reconstruction des transferts sédimentaires dans ces systèmes turbiditiques, nous discutons de l’impact relatif des différents facteurs forçant la sédimentation gravitaire sous-marine à haute-fréquence (eustatisme, climat, et tectonique). Pour cela, une étude stratigraphique détaillée a été réalisée sur la base de différents outils (datation radiocarbone, géochimie élémentaire, biostratigraphie) permettant de contraindre dans le temps les séries sédimentaires gravitaires. L’évolution des apports sédimentaires et des processus de dépôt au cours du Quaternaire terminal, en relation avec les modifications paléo-environnementales continentales, a permis d’identifier l’impact, l’importance relative et les interactions entre les forçages externes sur le développement à haute-fréquence (103-104ans) de systèmes de dépôt gravitaires, dans divers contextes géodynamiques. Les connaissances acquises sur la sédimentation du Golfe d’Oman ont finalement permis d’alimenter une base de données sédimentologique conséquente. L’intégration de cette base dans un modèle numérique géoacoustique (« simulateur ») développé par le SHOM a permis d’évaluer quantitativement l’impact des variations sédimentaires à différentes échelles (distribution spatiale, lithologie, stratification, processus de dépôt) sur la propagation du signal acoustique pour différentes gammes de fréquence (de 300 Hz jusqu’à 3 kHz) et angles d’émission (de 0 à 90°). Ces travaux constituent une base pour la réalisation d’un modèle géoacoustique régional robuste This study focuses on the Late Quaternary turbidite systems of the Gulf of Oman and the East-African margin (western Indian Ocean), previously poorly studied. It is based upon a compilation of acoustic data (bathymetry, multibeam imagery, 3.5 kHz and multi-channel seismic) and sedimentological data (küllenberg and calypso piston cores) recovered during several cruises leaded by the SHOM and IFP institutes. Turbidite system architecture and sedimentary processes revealed a strong variability primarily related to the physiographic, hydro-climatic and geodynamic context of each margin. High-resolution stratigraphy has been achieved using a combination of radiocarbon dating, XRF geochemistry, biostratigraphy). This allowed to investigate the impact, the interaction and the relative importance of the external forcings on deep water sedimentation (i.e. tectonics, climate and eustasy) at high- frequency (103 -104 yrs) in different tectonic setting (active & passive margins). Finally, integration of the sedimentological data set in a geoacoustic numerical modelling leaded to a first quantitative estimation of the regional relationship between sea-floor properties (lithology, depositional environment, stratification) and propagation of acoustic signal at 300 Hz- 3kHz frequencies and 0-90°. This work constitutes a basis for future geoacoustic modelling in the area

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Dissertations / Theses on the topic 'System margin'

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