A complexidade inerente ao processo de produção de energia apresenta um desafio aos especialistas quando estes se deparam com o dimensionamento e operação de sistemas de recursos hídricos. A produção energética de um sistema hidroelétrico depende fundamentalmente das séries de vazões afluentes às diversas usinas hidrelétricas do sistema. No entanto, a incerteza das vazões futuras e sua aleatoriedade são obstáculos que dificultam todo o planejamento da operação do sistema energético brasileiro. A inexistência de um software específico para análise de séries de vazões ocorridas nas usinas hidrelétricas, associada à importância desse tipo de dado no contexto energético, motivou a concepção de uma ferramenta gráafica para visualização e previsão desses dados. Acredita-se que a visualização desses dados por meio de representações apropriadas e altamente interativas possa promover hipóteses e revelar novas informações dos fenômenos associados a essas quantidades, melhorando a qualidade das decisões de planejamento do sistema energético. Este trabalho de mestrado apresenta em detalhes o sistema desenvolvido, chamado Power Map Explorer, e das técnicas nele implementadas / The complexity inherent to the process of energy production introduces a challenge to the experts when they are faced with dimension and operation of water resources systems. The energy production of a hidroeletric system depends on streamflow time series from hydroelectric plants located on different rivers of the system. However, the uncertainty and randomness of future streamflow series impose difficulties to the planning and operation of the brazilian energy system. The lack of a software suite to support the analysis of inflow series from hydroelectric plants, and the importance of this data in the energy context motivated the conception and implementation of a graphical tool to visualize and forecast this type data. The appropriate level of visualization and interaction with this type of data can spring new hypotheses and reveal new information, leading to performance improvement of the task of energetic planning. This work presents a software for visualization and forecast of inflow data series, the Power Map Explorer, in detail

<p>This master thesis was carried out at the Department of Aerodynamics and Flight Mechanics at Saab Aerosystems, Linköping, Sweden. It makes up the author’s final work prior to graduation in the field Applied Physics and Electrical Engineering at the Department of Electrical Engineering at The Linköping Institute of Technology (LiTH), Linköping, Sweden.</p><p> </p><p>The objective of the paper was to study a non-uniform helicopter rotor downwash model in forward flight for the unmanned helicopter Skeldar, which is under development at Saab. The main task was to compare the mentioned model with today’s uniform downwash model in order to find differences and similarities. This was done both from a modeling and a controlling perspective. To start with, an introduction is given which is followed by a helicopter theory chapter. The following three chapters deal with the theory of induced velocity, the helicopter model and the Linear Quadratic Regulator (LQR). Finally, the results are presented and discussed.</p><p> </p><p>The downwash models were derived using Momentum Theory (MT) and Blade Element Theory (BET). These two theories were combined in order to find a connection between the induced velocity and the rotor thrust coefficient. The non-uniform downwash model that was studied is proposed by Pitt & Peters and describes a linear variation of the induced velocity in the longitudinal plane.</p><p> </p><p>For the control, a LQ-regulator was chosen since it is easily implemented in MATLAB and it stabilizes the plant model by feedback and consequently creates a robust system. Before the controller could be implemented, the models had to be reduced and the states had to be divided into longitudinal and lateral ones.</p><p> </p><p>The comparison between the open systems clearly shows that differences in the inflow models propagate to all states and consequently the helicopter behaves differently in all planes. Great discrepancies are apparent for the angular velocities <em>p</em> and <em>q</em>. For Pitt & Peters’ model those states are believed to be strongly affected by the system’s positive real pole, causing a rather unstable behavior. When the systems were closed by feedback, the differences were reduced dramatically. Pitt & Peters’ model resulted in greater overshoots than the uniform model, but the overall behavior of all states was rather similar for the two models.</p><p> </p><p>It is concluded, that the adaption of Pitt & Peters’ inflow model does not make any substantial difference when a controller is implemented. The differences between the open systems, however, are reason enough to question Pitt & Peters’ model. In order to evaluate the non-uniform model properly, it has to be compared to suitable flight data which is still lacking up to this date.</p>

The Mabou Group in the Picadilly region of New Brunswick consists predominantly of red siltstones with interbeds of sandstone and conglomerate. The Mabou is of importance in this region as it overlies evaporite deposits of economic value. Given that the Mabou is several hundred meters thick, yet possesses no significant marker beds, it has remained stratigraphically undifferentiated in the Picadilly region over the course of previous regional mapping efforts in the area. Given the lack of a stratigraphic framework, coupled with insufficient hydrogeological sampling and test data to delineate any laterally extensive flow zones, the hydro-stratigraphy of this sedimentary package has not been established. Based on experience gained at other operations, Potash Corporation of Saskatchewan Inc. (PCS) recognized the need to take a proactive approach towards understanding the hydrogeology of the Picadilly mine development site. PCS has used a specialized technique in characterizing boreholes to measure depth-profiles of hydrophysical properties by logging the electrical conductivity of the borehole fluids over a period of time. Through the interpretation of these logging results, with the context provided by conventional geophysical logging data and nearby exploration drill core, this research seeks to identify zones of flow and assess whether or not any major units with lateral connectivity can be identified. The results highlight four zones of interest within the Mabou: the Upper Mabou; vuggy porosity directly above gypsum-infilled fractures; vugs and fractures within the Medium Sandstone subdivision; and the lower Mabou Siltstone at the base of the Mabou Group (within ~15m of base). Three of these zones are of interest as they tend to have relatively high permeabilities, with permeabilities over 10 000 md measured within the Upper Mabou, as high as 1800 md in the vuggy porosity zone directly above gypsum-filled fractures and as high as 1900 md within the Medium Sandstone subdivision . The fourth zone, found at the base of the Mabou Group, is of interest because the modest to low permeability recorded (as high as 38 md) is higher than the surrounding rocks and is in close proximity to the caprock of future mining activity. The permeabilities of the rocks studied in this research are believed to be dominantly controlled by secondary porosity. In the case of the permeable zone identified above the zone of gypsum-infilled fractures, relatively high porosities (9 to 15%) were interpreted from geophysical logs. These elevated porosities are due to the presence of vuggy porosity in this zone. However, no clear correlation between log-derived porosity and permeability was observed for the other permeable zones. This is believed to be due to the fact that fractures were the dominant control on porosity in these zones, and that the incremental contribution of fracture porosity to total porosity was too small to be readily identified.

This master thesis was carried out at the Department of Aerodynamics and Flight Mechanics at Saab Aerosystems, Linköping, Sweden. It makes up the author’s final work prior to graduation in the field Applied Physics and Electrical Engineering at the Department of Electrical Engineering at The Linköping Institute of Technology (LiTH), Linköping, Sweden.   The objective of the paper was to study a non-uniform helicopter rotor downwash model in forward flight for the unmanned helicopter Skeldar, which is under development at Saab. The main task was to compare the mentioned model with today’s uniform downwash model in order to find differences and similarities. This was done both from a modeling and a controlling perspective. To start with, an introduction is given which is followed by a helicopter theory chapter. The following three chapters deal with the theory of induced velocity, the helicopter model and the Linear Quadratic Regulator (LQR). Finally, the results are presented and discussed.   The downwash models were derived using Momentum Theory (MT) and Blade Element Theory (BET). These two theories were combined in order to find a connection between the induced velocity and the rotor thrust coefficient. The non-uniform downwash model that was studied is proposed by Pitt &amp; Peters and describes a linear variation of the induced velocity in the longitudinal plane.   For the control, a LQ-regulator was chosen since it is easily implemented in MATLAB and it stabilizes the plant model by feedback and consequently creates a robust system. Before the controller could be implemented, the models had to be reduced and the states had to be divided into longitudinal and lateral ones.   The comparison between the open systems clearly shows that differences in the inflow models propagate to all states and consequently the helicopter behaves differently in all planes. Great discrepancies are apparent for the angular velocities p and q. For Pitt &amp; Peters’ model those states are believed to be strongly affected by the system’s positive real pole, causing a rather unstable behavior. When the systems were closed by feedback, the differences were reduced dramatically. Pitt &amp; Peters’ model resulted in greater overshoots than the uniform model, but the overall behavior of all states was rather similar for the two models.   It is concluded, that the adaption of Pitt &amp; Peters’ inflow model does not make any substantial difference when a controller is implemented. The differences between the open systems, however, are reason enough to question Pitt &amp; Peters’ model. In order to evaluate the non-uniform model properly, it has to be compared to suitable flight data which is still lacking up to this date.

The hydrothermal scheduling problem aims to determine an operation strategy that produces generation targets for each power plant at each stage of the planning horizon. This strategy aims to minimize the expected value of the operation cost over the planning horizon, composed of fuel costs to operate thermal plants plus penalties for failure in load supply. The system state at each stage is highly dependent on the water inflow at each hydropower generator reservoir. This work focuses on developing a probabilistic model for the inflows that is suitable for a multistage stochastic algorithm that solves the hydrothermal scheduling problem. The probabilistic model that governs the inflows is based on a dynamic linear model. Due to the cyclical behavior of the inflows, the model incorporates seasonal and regression components. We also incorporate climate variables such as precipitation, El Ni\~no, and other ocean indexes, as predictive variables when relevant. The model is tested for the power generation system in Brazil with about 140 hydro plants, which are responsible for more than 80\% of the electricity generation in the country. At first, these plants are gathered by basin and classified into 15 groups. Each group has a different probabilistic model that describes its seasonality and specific characteristics. The inflow forecast derived with the probabilistic model at each stage of the planning horizon is a continuous distribution, instead of a single point forecast. We describe an algorithm to form a finite scenario tree by sampling from the inflow forecasting distribution with interstage dependency, that is, the inflow realization at a specific stage depends on the inflow realization of previous stages. / text

Baigiamojo bakalauro darbo tema – Mūšos upės taršos problemų analizė. Darbo tikslas – ištirti Mūšos upės taršą įtakojančius veiksnius. Aprašytos į Mūšą sutekančios Kulpės, Kruojos, Daugyvenės, Tatulos ir Lėvens upės, jų vandens kokybė bei į Mūšos upę iš šių intakų atplukdomi teršalų kiekiai. Pateiktas hidrocheminis upių įvertinimas. Analizuojama mokslinė literatūra paviršinio vandens apsaugos klausimais. Pateikiamos žinios apie Mūšos upės būklę. Atlikti Kulpės, Kruojos, Daugyvenės, Tatulos, Lėvens upių vandens užterštumo tyrimai. Mūšoje vandens tarša matuota aukščiau Kulpės, Mūšoje žemiau Saločių bei UAB „Searimner“ kiaulių komplekso „Mūša“ teritorijoje esančiame drenažo vandenyje. Mėginiai buvo paimti vietose: vienas aukščiau miestų (Mūša aukščiau Kulpės), kiti penki mėginiai upių žiotyse – prieš įtekant į Mūšos upę, vienas šalia kiaulių komplekso esančio drenažo pabaigoje prie įtekėjimo į Mūšą, vienas 14 km nuo Latvijos sienos, žemiau Saločių gyvenvietės. Vandens mėginiuose ištirta: vandens pH, temperatūra, skendinčių medžiagų kiekis (SM), BDS7, amonio azoto, nitritų, nitratų, bendrojo azoto, bendrojo fosforo bei fosfatų koncentracijos. Ištirtuose vandens mėginiuose pH svyravo nuo 7,66 iki 8,07. BDS7 viršijo didžiausią leistiną koncentraciją visose tirtose upėse nuo 1 – 4 kartų, išskyrus taške Mūša aukščiau Kulpės. Amonio azoto koncentracija Kulpės žiotyse DLK (0,78 mgN/l) viršyta 5 kartus. Nitritai didžiausią leistiną koncentraciją viršija Kulpės (1,6 karto), Lėvens (2... [toliau žr. visą tekstą] / Bachelor thesis – pollution problems analysis in river Mūša. The aim of the work – to analyse the key issues which influence pollution in river Mūša. Provided description of inflow rivers like Kulpė, Kruoja, Daugyvenė, Tatula and Lėvuo, their water quality and also their level of pollution flow to river Mūša. Evaluation of these rivers hydro-chemical state provided. Moreover, there is scientific literature analysis about protection questions of surface water. Information about the state of river Mūša provided. Water pollution examples were taken in Kulpė, Kruoja, Daugyvenė, Tatula and Lėvuo. In Mūša water pollution was measured before Kulpė inflow, another test was taken after Saločiai village and one more from drainage water in the territory of pig complex called “Mūša”. Examples were taken from: one before the city’s (Mūša before Kulpe inflow), other five examples near the estuary, before inflow to Mūša. One more example was taken from drainage before inflow to Mūša near the pig complex and last one 14 kilometres from Latvian border, before Saločai village. Analysed water examples revealed: water pH, temperature, flowing material quantity (SM), BDS7, ammonium nitrogen, nitrite, nitrate, total nitrogen, total phosphor and phosphates concentration. In analysed water examples pH falter from 7,66 to 8,07. BDS7 exceeded highest permitted concentration in all analysed rivers from 1 to 4 times, except point Mūša before Kulpe inflow. Ammonium nitrogen... [to full text]

In highly iterative development processes, functionality is continuously added while existing faults are repaired simultaneously. Therefore, practitioners need means to predict the fault inflow, i.e. the number of faults at the a certain project stage, in order to allocate resources adequately. This study investigates the use of software reliability growth models (SRGMs) for predicting fault inflow. Additionally, a simple linear model is developed and compared to the SRGMs. The paper provides results from applying these models on fault data from three different industrial projects. One of the key findings of this study is that SRGMs are applicable for predicting fault inflow in highly iterative processes. Moreover, the results show that a linear model provides reasonably accurate predictions as well and therefore, represents a valid alternative to the SRGMs.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20180号 / 理博第4265号 / 新制||理||1613(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 太田 耕司, 准教授 栗田 光樹夫, 教授 長田 哲也 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

Lopez Lake Reservoir is the primary source of potable water for the Cities of Arroyo Grande, Grover Beach, Pismo Beach, and to the Community Service Districts of Oceano and Avila Beach. In this study, a water balance and sediment yield analysis model was developed for the reservoir’s watershed. The model was used to estimate evaporation from the lake and to examine the effects of a wildfire on the reservoir. Evaporation and wildfire are dependent on variables that change on a spatial and temporal scale, making modeling challenging. The County of San Luis Obispo uses pan coefficients to estimate evapotranspiration losses from the reservoir. In this study, a water balance model was developed using a watershed model known as Soil and Water Assessment Tool, SWAT. Evaporation loss from the lake was calculated using the inflows simulated by the model, and other fluxes (e.g., water released for consumption to Arroyo Grande Creek, precipitation) that were obtained from the County of San Luis Obispo. The evaporation values estimated by the pan coefficient model were significantly higher than the water balance and the Penman-Monteith predictions. The Penman-Monteith method estimates seem more reasonable for the lake. SWAT was also used to simulate effects of a wildfire on sediment inflow and sediment yield into the reservoir for a year after a simulated fire. Results showed that sediment inflow rates increased by a factor of 3 following the simulated wildfire. Lopez Lake Reservoir’s capacity would be significantly affected by a wildfire. To improve the evaporation estimates it is recommended that the County of San Luis Obispo install streamflow gauges to measure the inflow into the reservoir. Using the streamflow gauges the reservoir evaporation could be calculated using the water balance method. Adding climate gauges at the reservoir would increase the accuracy of the Penman-Monteith method. Sediment gauges in the watershed would provide a calibration data source for the model as well as data collection points in the event of an actual wildfire.

<p> A dissolved oxygen model for stratified lakes is developed and is verified for Lake Ontario. The processes affecting the dissolved oxygen budget of a lake including hydraulic inflow and outflow, production and decomposition, atmospheric reaeration, vertical transport across the thermocline, and sediment oxygen demand are analyzed and quantified. The production and decomposition oxygen fluxes are provided by a phosphorus model developed by others. These phosphorus-oxygen inter-relationships are quantified using stoichiometry developed for oceans. Nine years of temperature data for Lake Ontario are used to estimate the annual variations of epilimnetic temperatures, the rate of deepening of the epilimnion (i.e. thermocline depth vs time) and the vertical exchange coefficient. Dissolved oxygen data over a similar period are used to estimate lake-wide concentrations of DO. The vertical exchange and decomposition hypolimnetic oxygen fluxes are estimated from observed data. Model predictions of concentrations and fluxes compare favourably to the observed data. This provides some verification for the predictions of the oxygen model, the oxygen-phosphorus stoichiometry and the decomposition flux predicted by the phosphorus model.</p> / Thesis / Master of Engineering (MEngr)