Tsunamis are among the most terrifying and complex physical phenomena potentially affecting almost all coastal regions of the Earth. Tsunami waves propagate in the ocean over thousands of kilometres away from their generating source at considerable speeds. Among several other tsunamis that occurred during the past decade, the 2004 Indian Ocean Tsunami and the 2011 Tohoku Tsunami in Japan, considered to be the deadliest and costliest natural disasters in the history of mankind, respectively, have hit wide stretches of densely populated coastal areas. During these major events, severe destruction of inland structures resulted from the action of extreme hydrodynamic forces induced by tsunami flooding. Subsequent field surveys in which researchers from the University of Ottawa participated ultimately revealed that, in contrast to seismic forces, such hydrodynamic forces are not taken into proper consideration when designing buildings for tsunami prone areas. In view of these limitations, a novel interdisciplinary hydraulic-structural engineering research program was initiated at the University of Ottawa, in cooperation with the Canadian Hydraulic Centre of the National Research Council, to help develop guidelines for the sound design of nearshore structures located in such areas. The present study aims to simulate the physical laboratory experiments performed within the aforementioned research program using a single-phase three-dimensional weakly compressible Smoothed Particle Hydrodynamics (SPH) numerical model. These experiments consist in the violent impact of rapidly advancing tsunami-like hydraulic bores with individual slender structural elements. Such bores are emulated based on the classic dam-break problem. The quantitatively compared measurements include the time-history of the net base horizontal force and of the pressure distribution acting on columns of square and circular cross-sections, as well as flow characteristics such as bore-front velocity and water surface elevation. Good agreement was obtained. Results show that the magnitude and duration of the impulsive force at initial bore impact depend on the degree of entrapped air in the bore-front. The latter was found to increase considerably if the bed of the experimental flume is covered with a thin water layer of even just a few millimetres. In order to avoid large fluctuations in the pressure field and to obtain accurate simulations of the hydrodynamic forces, a Riemann solver-based formulation of the SPH method is utilized. However, this formulation induces excessive numerical diffusion, as sudden and large water surface deformations, such as splashing at initial bore impact, are less accurately reproduced. To investigate this particular issue, the small-scale physical experiment of Kleefsman et al. (2005) is also considered and modeled. Lastly, taking full advantage of the validated numerical model to better understand the underlying flow dynamics, the influence of the experimental test geometry and of the bed condition (i.e. dry vs. wet) is investigated. Numerical results show that when a bore propagates over a wet bed, its front is both deeper and steeper and it also has a lower velocity compared to when it propagates over a dry bed. These differences significantly affect the pressure distributions and resulting hydrodynamic forces acting on impacted structures.

Germany is one of the pioneer countries in wind turbine technology. They installed many wind turbines during the last decades and are now confronted with a shortage of land suitable for new wind parks. Now, with an estimated wind turbine service life of 20 – 25 years whole wind parks are becoming obsolete and owners have to decide whether do decommission, repower or to continue the operation of their parks. The advantages of repowering as well as the bureaucratic hurdles are outlined and evaluated. This thesis deals with the repowering potential in North Rhine-Westphalia and is analysing the technical and economical possibilities of repowering. The main objectives are to identify wind turbines eligible for repowering and also to develop repowering scenarios in order to determine their techno-economic feasibility.  The designed steps of the methodology allow the census and the subsequent implementation of the results in WindPro and RETScreen.

Sweden wants to produce 100% of its electricity from renewable energy sources by 2040 and achieve net zero greenhouse gas emissions by 2045. While wind power is key to this transition, the permit process for large onshore wind power projects is one of the major challenges the country is currently facing, specifically the provision on municipal approval in the Environmental Code, the so-called municipal veto. To facilitate the expansion of wind projects in Sweden, the double testing of wind power applications was abolished in 2009, and the municipal veto was introduced to preserve the municipalities’ planning influence. However, the municipal veto contributed to a less predictable and legally secure permit process and became the main reason behind the rejections of wind power applications. Today, in 2021, the Swedish Government assigned a special investigator to examine and propose possible changes to the municipal veto provision. Though the municipalities believe that the veto is essential for their self-government and planning monopoly, the Swedish Energy Agency and the Swedish Environmental Protection Agency argue that the municipal authority should be exercised through the municipal general planning documents. Therefore, this thesis aims to verify the authorities’ argument by examining the relationship between the municipalities’ planning conditions for wind power and the permit decisions. The study is performed in collaboration with Westander Klimat och Energi and is based on 206 large onshore wind power applications between 2014 and 2020. The main research methods consist of a document analysis and of statistical analyses, namely simple percentages, and the chi-square test of independence, along with Cramer’s V calculation. The projects are categorized mainly based on the municipal planning conditions, and the permit decisions are analyzed accordingly. Essentially, it is shown that, even if not legally binding, the municipal general spatial planning documents constitute a valuable tool for the planning of onshore wind power projects in Sweden. Furthermore, the municipal planning conditions and permit decisions are not independent, however, their strength of association is weak. Nonetheless, the statistics indicate that in areas designated as suitable, more cases are likely to receive an approval than expected, and in areas not designated as suitable, the applications are more likely to be revoked than one would expect. In conclusion, it is important to invest resources into the strategic wind power planning at the local level. Also, the municipal plans must be kept updated to consistently reflect the municipalities’ intentions towards the use of their land and water areas.

Die Effekte des Klimawandels sind spürbar und es sind Maßnahmen erforderlich, diese schwerwiegenden Auswirkungen zu kontrollieren oder zu verringern. Diese Maßnahmen beinhalten die Vermeidung von Treibhausgasemissionen oder die Reduktion der atmosphärischen Konzentration sowie eine Anpassung an das vorhandene Klima und seine Auswirkungen. Erneuerbare Energiequellen tragen zur Eindämmung des Klimawandels durch die Reduzierung von Treibhausgasen konventioneller Energiequellen bei. Wie auch alle anderen sauberen Energiequellen spielt die Windenergie durch Reduzierung des CO2-Ausstoßes eine entscheidende Rolle bei der Bekämpfung des Klimawandels. Deutschland und Schottland sind beide Vorreiter bei der Entwicklung und Gewinnung landgebundener Onshore-Windenergie. Beide Staaten haben Im Rahmen ihrer Planungspolitik ehrgeizige Zielsetzungen durch Reduzierung von Treibhausgasemissionen die Auswirkungen des Klimawandels in Grenzen zu halten. In Deutschland und Schottland werden die Entwicklungen der Onshore-Windenergie durch Raumordnungsverfahren gesteuert, nach denen in der Regel Umweltverträglichkeitsprüfungen durchgeführt werden. In der Tat werden Umweltverträglichkeitsbewertungen als Mittel zur Umsetzung des Klimaschutzes in den Raumordnungsverfahren benutzt. Diese Forschungsarbeit soll zu einem strategischen Ansatz für die Entwicklung der Onshore-Windenergie in Deutschland und Schottland beitragen, wobei das Ausmaß der durch den Klimawandel verursachten Probleme und die klimatischen Faktoren der SEA in Raumordnungsverfahren auf regionaler und lokaler Ebene bei der Onshore-Windenergieplanung berücksichtigt werden. Diese Untersuchung hilft, die Beziehung zwischen SEAs prozessualer Wirksamkeit und den Herausforderungen bei der Umsetzung in Hinblick auf die Auswirkungen des Klimawandels in Deutschland und Schottland für die Onshore-Windenergiebranche besser verständlich zu machen. Der methodische Rahmen basiert auf der Auswertung relevanter Gesetze und Vorschriften, Grundsatzdokumenten und wissenschaftlicher Literatur bezüglich der Umweltbewertung von Onshore-Windplanungen. Zusätzlich wurden Experten befragt und Fallstudienanalysen deutscher und schottischer Onshore-Windenergiepläne durchgeführt. Ein Vergleich der Ergebnisse beider Länder zeigt, dass sowohl Deutschland als auch Schottland die SEAs auf politischer Ebene verbessern müssen, um die Auswirkungen des Klimawandels auf verschiedenen räumlichen Ebenen angehen zu können. Die Studie zeigt ferner, dass es gleichermaßen wichtig ist, aktuelle und zukünftige Trends des Klimawandels und des Windverhaltens mithilfe von Klimamodellen zu verfolgen, da diese Informationen dazu beitragen, das komplexe Phänomen des Klimawandels und dessen Auswirkungen effizient anzugehen. Die Studienergebnisse zeigen auch den Einfluss der SEA auf die Onshore-Windenergieplanung in Deutschland und Schottland in Hinblick auf Abschwächung und Anpassung der Auswirkungen des Klimawandels mit der Betonung der Notwendigkeit eines hohen Maßes an politischer Unterstützung, um die Belange des Klimawandels in die Onshore-Windenergie Planungsaktivitäten integrieren zu können. Auf dieser Grundlage wird empfohlen, in der Raumplanung der Onshore-Windenergieentwicklung die Auswirkungen des Klimawandels als ein kritisches Thema zu erkennen und auf den verschiedenen Planungsebenen wirksam zu berücksichtigen. Darüber hinaus sind für die Onshore-Windenergieplanungen starke politische Zielsetzungen erforderlich, um die Entscheidungsfindungen im Bereich des Klimawandels zu unterstützen.

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There is a need for an efficient adjustment of the energy supply system towards renewable energy resources in the near future. This raises the question whether it is financially efficient to repower an onshore wind turbine or wind farm in operation with respect to specific surrounding conditions? To this purpose, the objective of this Thesis is a quantitative analysis of a wind power project repowering addressing certain legislative parameters, varying economic factors and WT models respectively. To enable this analysis, a case-study considering a number of hypothetical scenarios for repowering a wind farm in Germany has been applied. The scenarios address in particular the widely implemented limitation in overall building heights of 100m depending upon varying economical parameters. Nevertheless, this case-study applies three different WT models whereof one model matches the legislations and the other two models exceed the legislations by a varying degree in order to evaluate a potential productivity growth. The varying economic conditions are represented by a base case projection applying average wind power construction costs and financial rates whereas a best case and worst case projection consider deviating interest rates, capacity factors, investment and O&M costs respectively.   The economic calculations together with the determination of the capacity factor with respect to each WT model are performed by utilising the decision aid tool RETScreen. The results obtained by this case-study show versatile economic and technological performance. WT models of minor size addressing in particular local existing legislation regarding the limitation of overall height which must not exceed 100m are inefficient regardless of varying economic conditions. Exceeding the limitation, WT models provide a significant increase in performance and thus return positive economic results independent of varying economic conditions. The main conclusion is that existing local legislations based on previous considerations from the past but which no longer correspond to the state of technology have to be questioned in general or have to be mitigated by subsidy instruments in order to support a generation shift in technology before the end of life of operational wind farms and thus promptly increase efficiency by repowering.

台股基金淨資產規模在2007年10月底創下5,251億元台幣高水位後，隨即因全球次貸危機而一路挫低至2009年1月的2,283億元台幣，衰退幅度高達56.5%。之後雖逐漸自風暴中走出，但至今仍未再現5,000億元規模時之風華。因此，台股基金市場成長受限之論點四處流竄。為客觀實證台股基金市場未來成長性之可能走向，本研究擬運用複迴歸分析模型探討市場論點--「台股基金市場成長性受限」之可信度。 本研究係以台股基金單位數月變動量為被解釋變數，並擇取外銷訂單月變動量、台銀一年期定存利率月變動量、台灣加權指數月底收盤變動量、外資月買/賣超金額、整體台股基金平均月報酬率相對大盤月報酬率、整體台股基金Sharpe ratio相對大盤Sharpe ratio、台股基金月變動檔數、ETF單位數月變動量、境外基金業務、全權委託業務、1997亞洲金融風暴及2007全球次貸危機等12項數列為解釋變數，進行必要之調整後，以複迴歸模型分析而得具顯著解釋力之模型。 而分析模型中的12個解釋變數，有8個變數p-value在5%顯著水準之下，具顯著解釋力。僅外銷訂單月變動量、ETF單位數月變動量、境外基金業務及2007全球次貸危機對台股基金單位數變動量之解釋力不顯著。 此外，複迴歸分析模型所呈現之樣本外預測值僅於窄幅中波動，顯示2010/11-2011/12台股基金單位數預測值變動幅度不大。而Holt Winters所呈現之預測值更顯露出疲態，呈現一等差下降趨勢。此分析結果正與市場論點--「台股基金市場成長性受限」一說相呼應。 / October 2007, net assets of Taiwan domestic equity funds reached the historical high, NT$ 525.1billion. After that, net assets setback to NT$ 228.3 billion in January 2009 due to global subprime mortgage crisis, declining by as much as 56.5%. Although the market has gradually ridden out the crisis, the fund scale has not yet retrieved the plateau of NT$ 500 billion. Therefore, an argument is ubiquitous in the market which implies that the growth potential of Taiwan domestic equity fund has been capped. For verifying the credibility of this argument, the empirical study would apply for multiple regression to research it. This study defines monthly changes in Taiwan domestic equity fund units as a dependent variable. 8 out of 12 explanatory variables which p-values are below the 5% significance level tend to reject the null hypotheses. That represents these variables are significantly explanatory. Monthly changes in the amount of export orders, monthly changes ETF units, offshore fund business and the 2007 subprime mortgage crisis are only 4 variables which are not significantly explanatory for dependent variable. In addition, multiple regression analysis model shows that fund unit forecasts from Nov. 2010 to Dec. 2011 fluctuate in a very narrow range. That reveals the forecasted fund units among Nov. 2010 – Dec. 2011 just have modest changes. At the same time, the forecasted fund units from Holt Winters expose the weakness, showing a downward trend in arithmetic. Both of results from multiple regression and Holt Winters seem to identically echo the market argument –‘the growth potential of Taiwan domestic equity fund market has been capped.’

Made available in DSpace on 2014-12-17T14:52:40Z (GMT). No. of bitstreams: 1 MariaAD.pdf: 1151403 bytes, checksum: ec2a5410864dfc28e3a9b2591ef3f6f8 (MD5) Previous issue date: 2008-04-28 / This master?s thesis presents a reliability study conducted among onshore oil fields in the Potiguar Basin (RN/CE) of Petrobras company, Brazil. The main study objective was to build a regression model to predict the risk of failures that impede production wells to function properly using the information of explanatory variables related to wells such as the elevation method, the amount of water produced in the well (BSW), the ratio gas-oil (RGO), the depth of the production bomb, the operational unit of the oil field, among others. The study was based on a retrospective sample of 603 oil columns from all that were functioning between 2000 and 2006. Statistical hypothesis tests under a Weibull regression model fitted to the failure data allowed the selection of some significant predictors in the set considered to explain the first failure time in the wells / Esta disserta??o apresenta uma aplica??o do estudo da confiabilidade em dados de tempo de vida de po?os petrol?feros terrestres produtores de ?leo da Bacia Potiguar (RN/CE). A vari?vel resposta do nosso estudo ? o tempo de funcionamento do po?o dentro de sua normalidade at? apresentar a primeira falha relacionada a equipamentos de subsuperficie, que cause uma parada total no funcionamento do po?o. O principal objetivo do estudo foi, com base em um conjunto de dados reais fornecidos pela PETROBRAS, verificar a exist?ncia do relacionamento do tempo de vida com diversas caracter?sticas dos po?os como, m?todo de eleva??o utilizado, quantidade de ?gua produzida (BSW Basic Sediments and Water), Raz?o G?s ?leo (RGO), profundidade de instala??o da bomba, unidade operacional de origem, entre outras. Neste trabalho foi feito um estudo retrospectivo com uma amostra composta por 603 po?os-colunas que estavam em funcionamento no per?odo de 2000 a 2006. A modelagem probabil?stica dos dados foi feita atrav?s do ajuste do modelo de regress?o Weibull. O ajuste deste modelo se mostrou apropriado aos dados e permitiu avaliar, atrav?s de testes estat?sticos de hip?teses, os fatores significativamente relacionados com o tempo at? a falha dos po?os

Modelling the wake effect generated by wind turbines is an essential part for calcu- lating a wind farm’s expected energy production. Operating wind turbines disturb the flow of the wind, which results in decreased production of downwind turbines. The N. O. Jensen model is an industry standard wake model that assumes a linear expansion of the downstream wake. The only adjustable parameter in the model is the wake decay constant (WDC), which has traditionally been derived semi em- pirically from terrain surface roughness. However, the WDC defines the expansion rate of the generated wake, and therefore can be linked to the ambient turbulence intensity (TI): high ambient turbulence leads to a faster decay of the generated wake, and therefore to lower wake losses, and vice-versa. Since the influence of the roughness on the ambient turbulence intensity is expected to be less significant at higher heights, these roughness-based WDC values are rather uncertain for the hub heights employed nowadays. The following study presents the results of a comparison between observed and mod- elled wake losses based on different WDC values. To investigate how a change in height affects the wake modelling, two wake scenarios occurring between two tur- bine sets with different hub heights are selected from an operational wind farm. By modelling the wakes using roughness as well as turbulence intensity-based WDCs, conclusions can be drawn on how the predictive capability of the N.O. Jensen model depends on the selection of a suitable WDC value. Finally it is concluded that the goodness of fit between modelled and observed wake losses shows a clear dependency on the wind speed/power production inter- val. At higher wind speeds, the TI-based WDC resulted in a better accuracy of the modelled wake losses as compared to the roughness-based WDC, while for lower wind speeds the N. O. Jensen model performed most accurately when using WDC = 0.075. However, for the investigated cases the overall accuracy of the modelled wake appears to be higher when choosing WDC = 0.075 instead of a TI-based WDC.

Thesis focuses on the possibility of setting up business entities in tax havens and their utilization in tax optimization. Reader is introduced to the most interesting Offshore and Onshore localities, their advantages, risks and possibilities of use. I will clarify the nature of the tax advantages of various types of companies including explanations of terms come from angloamerican jurisdictions. I will describe the specific steps which are required to set up the company in Grenada, including Sample documents and a model example demonstrating the tax optimization of the hypothetical bussines company. The resulting structure of the company will be subject to lower tax burden and consequently increase competitiveness of its products in global markets.