This thesis deals with the design of a permanent-magnet synchronous inner rotor motor for an in-wheel application for the Shell Eco Marathon Urban concept vehicle. First of all, concepts related to permanent magnet motors are studied. Likewise, different features of permanent magnet motors are qualitatively evaluated in order to choose the most suitable. A radial flux motor is selected based on its solid, economic and acceptable characteristics. Next, a detailed study of concentrated windings is carried out. Through this investigation, undesirable configurations of pole and slot numbers due to unbalanced magnetic pull or a low fundamental winding factor will be avoided and how to determine the different winding layouts for different pole and slots configuration will be explained. As well, based on this study, and the magnetic and electric behavior of the machine, an analytical model is created. This model calculates the optimum size and characteristics of a machine in order to obtain lightweight design. After that, the design of a program based on a finite element method that simulates different situations for the machine is accomplished, dealing with the difficulties that entails the concentrated windings. Finally, through the use of this program, the machine calculated by the analytical model is analyzed, specially regarding that it does not surpass some important margin in order not to be demagnetized or not to surpass the maximum phase voltage supplied by the batteries.

No description available.

La evaluación de daños de inundaciones, sismos, huracanes entre otros fenómenos en el mundo son analizados con metodologías como las curvas de vulnerabilidad. En el Perú, los desastres originados por flujos hiperconcentrados aún son alarmantes debido al cambio climático e incremento de la intensidad de fenómenos como el niño costero (FENC). Por ello, la presente tesis desarrolla curvas de vulnerabilidad para viviendas de albañilería confinada de 1 y 2 pisos de la Urb. San Idelfonso en Ica, relacionando la variable: profundidad de flujo, asociado al evento producido por las lluvias intensas en la cabecera de la quebrada Cansas que desencadenó el FENC 2017, y el porcentaje de daño: basado en la metodología del Cuerpo de Ingenieros de Estados Unidos (USACE), cuya formulación es la relación entre el valor de reparación entre valor total de la vivienda. Los importes monetarios y partidas de la vivienda fueron obtenidos de la resolución ministerial RM 415-2017-VIVIENDA. El proceso consiste en el modelamiento hidrológico en HEC-HMS, hidráulico en FLO-2D, estimación del porcentaje de daño y generación de las curvas de vulnerabilidad. Se han contrastado las curvas de vulnerabilidad para flujos hiperconcentrados (lodos) con investigaciones de curvas generadas para inundaciones y flujo de detritos. Los resultados demuestran que el evento del 2017 tuvo una afectación económica de al menos 1.3 millones de soles. Finalmente se generaron mapas de daños para los TR de 10, 20, 50, 100, 150 y 200 años y se calcularon los importes monetarios de reparación por vivienda en la Urb. San Idelfonso. / The damage assessment from floods, earthquakes, hurricanes among other phenomena in the world are analyzed with methodologies such as vulnerability curves. In Peru, disasters caused by hyper-concentrated flows (muds) are alarming due climate change and the increased intensity of phenomena such as “El Niño Costero (FENC)”. Therefore, the present thesis develops vulnerability curves for 1 and 2 story confined masonry buildings of the Urb. San Idelfonso – Ica, relating the variable: flow depth, associated with the event produced by the heavy rains at the head of “Quebrada Cansas” caused by FENC 2017 and the percentage damage: based on the methodology of the United States Corps of Engineers (USACE), whose formulation is the repair value between total building value. The monetary amounts and items of the building are obtained from the RM 415-2017-VIVIENDA. The process consists of hydrological modeling in HEC-HMS, hydraulic modeling in FLO-2D, estimation of the percentage of damage and generation of vulnerability curves. Vulnerability curves for hyper-concentrated flows (muds) have been contrasted with investigations of curves generated for floods and debris flow. The results show that the 2017 event had an economic impact of at least 1.3 million soles. Finally, damage maps were generated for the TR of 10, 20, 50, 100, 150 and 200 years and the monetary amounts for building repair in Urb. San Idelfonso were calculated. / Tesis

No description available.

Syftet med den här studien är att med kvantitativ metod undersöka om samband föreligger mellan låg socioekonomisk status och förekomst av brott i nära relation i landets kommuner. Regressions- samt geografisk analys används för att studera socioekonomiska faktorers påverkan på frekvensen i antalet anmälda brott i nära relation, samt belysa geografiska variationer i brottsnivå. Resultatet ger stöd för hypotesen samt vad som förväntades utifrån teorin om social desorganisation samt strainteori avseende socioekonomiska faktorers samband med nivåer av våld i nära relation. Vi kan dock inte utesluta vare sig medierande eller modererande faktorer som tidigare forskning visat på. För det krävs vidare forskning. Våld i nära relation skulle alltså, baserat på resultaten, vara mer sannolikt att förekomma i kommuner med högre andel individer med låg socioekonomisk status. Följaktligen bör sannolikt brottspreventiva åtgärder som syftar till att motverka effekterna av låg socioekonomisk status även motverka förekomsten av våld i nära relation. / This study considers the effects of concentrated disadvantage on the prevalence of intimate partner violence (IPV) in Sweden. The purpose is to quantitatively study the relationship between rates of reported IPV to police. Multiple regression analysis is used to examine the relationship between socioeconomic factors and differences in crime rates among municipalities. Geographical analysis is used to examine variations in crime rates between municipalities. The results seemingly confirms the hypothesis that concentrated disadvantage significantly increases intimate partner violence, as expected from social disorganization and strain theory. However, we can not rule out the possibility of mediating and/or moderating factors as indicated from previous studies abroad. For that, further research needs to be done. Based on the results, municipality representatives should consider crime prevention strategies aimed at decreasing the effects of concentrated disadvantage among residential areas.

Solar energy is of huge interest due to the current situation with global warming. A number of solar technologies have been developed, such as photovoltaic, concentrated solar power, and solar water heating systems, to name a few. However, the technologies are being slowly implemented, and Botswana, with generous amounts of sun, is particularly suitable for solar energy. The opportunities were investigated due to the overwhelming and horrifying warnings echoed by many of the world's scientists regarding global warming. First, a handful of solar technologies were thoroughly investigated. A field study at Gakgatla village was then conducted, where the locals were interviewed. The interviews were analyzed, and solutions were suggested based on the identified needs of the locals. The biggest challenges identified were the lack of electricity in many of the households, parental figures not being supportive of the children's education, and theft. Additionally, many locals cooked with firewood. The most helpful solution but difficult to implement is photovoltaic panels. Solar water heating systems would also be helpful to the locals who predominantly had cold water. Additionally, solar cookers could help minimize exposure to hazardous smoke. Lastly, solar lamps could help students study during nighttime. Some locals also showed huge enthusiasm for what the future partnership with Botho University will bring. It is encouraged to develop a prototype of a solar cooker, particularly the parabolic solar cooker, in order to install solar cookers in Gakgatla village. Solar dryers would also greatly benefit the locals and are also suggested developments. Both of the mentioned solutions would help minimize the locals' exposure to the hazards of cooking with firewood. The solar dryers will also help eliminate bacteria by drying the food in a protected space inside a container.

One of the key challenges the world will need to face during the 21st century is global warming and the consequent climate change. Its presence is indisputable, and decarbonizing the gird emerges as one of the required pathways to achieve global sustainable objectives. Solar energy power plants have the potential to revert this situation and solve the problem. One way to harness this energy is through Concentrated Solar Power plants. The major advantage and potential of this technology is its ability to integrate cost-effective Thermal Energy Storage (TES), which is key with such an inherently intermittent resource. On the other hand, the drawback is the high current Levelized Cost of Energy (LCOE). The other main way to harness that highlighted solar energy is the use of Photovoltaic panels, which have recently achieved very competitive LCOE values. On the other hand, the storage integration is still a very pricey option, normally done with Battery Energy Storage Systems (BESS). As a conclusion, a hybrid power plant combining the LCOE of the PV and the TES of the CSP emerges as the key way of achieving a very competitive solution with a big potential. This master thesis aims at exploring the possibilities of a hybrid CSP and PV power plant with a sCO2 power cycle, integrated in the primary, secondary and tertiary electricity markets. To achieve this purpose, firstly, a Python-based Energy Dispatcher was developed to control the hybrid power plant. Indeed, the Dispatcher is the tool that decides when to produce, when to store… following an optimization problem. This can be formulated mathematically, and that was done and integrated into the Python code using Pyomo, a software for optimization problems. As a result, the Dispatcher achieved an effective control of the plant, showing intelligent decisions in detailed hourly analyses. The results were very promising and included optimization functions as maximizing the profitability of the plant or the total production, among others. To proceed with the Techno-economic assessment of the hybrid plant, the electricity markets were studied. The main source of income of any power plant is normally the revenue from selling electricity to the grid, but since there are several markets, there are also other possibilities. In this thesis, it was assessed from a Techno-Economic perspective how the performance and optimal design of the plants vary when providing different services extra to selling electricity to the grid. The conclusion was that even though the Net Present Value (NPV) achieved working on the spot market was already very high, the extra value added from participating in the secondary or tertiary markets was indisputable. Indeed, the profits attained in those markets were between two and four times higher than the ones of the spot market. This is a specific case, but a trend was identified: these hybrid power plants have a huge possibility and a bright future on the service markets. As a consequence, this thesis shows the huge potential of hybrid power plants integrated in the grid participating in several markets. It also lays the foundation for future studies in other locations, under different conditions and with different technologies, among others.

<p>  </p> <p>Concentrated solar power (CSP) is a technology that utilizes focused sunlight to heat a high-temperature medium (such as a molten salt). Heat from this medium can be transferred to a working fluid (such as supercritical CO2) that is then used to drive a turbine to generate electricity. Alternatively, the hot medium/fluid can be pumped into tanks for thermal energy storage (TES), for heat extraction later to generate dispatchable electricity and/or for electricity production at night or on cloudy days. By increasing the fluid temperature to <u>></u>750oC and utilizing TES, CSP can become more cost competitive with fossil-based electricity production. Current CSP systems utilize molten nitrate salts for heat transfer and TES that are known to thermally degrade at temperatures >600oC. To achieve temperatures <u>></u>750oC, molten chloride salts, such as ternary MgCl2-KCl-NaCl compositions, are being considered as heat transfer and thermal energy fluids for next generation CSP plants due to their higher temperature stability, low cost, and availability. </p> <p>In this work, it was demonstrated that MgCl2-containing molten salts are prone to oxidation in ambient air at 750oC, which can enhance corrosion of the containment materials and alter the thermophysical properties of the fluid. An alternative, low-cost, earth-abundant, MgCl2-free, oxidation-resistant molten salt, a eutectic CaCl2-NaCl composition, was developed, along with a corrosion mitigation strategy, to enable the slow growth of protective oxide layers on metals that are resistant to dissolution by such MgCl2-free molten chloride salts. </p> <p>This strategy was expanded to other low-cost, oxidation resistant compositions, such as eutectic BaCl2-CaCl2-KCl-NaCl with tailored chemical and thermophysical properties for CSP and TES. The melting temperature, heat capacity, oxidation resistance, and crystallization behavior were measured for eutectic a BaCl2-CaCl2-KCl-NaCl(17.5-47.8-3.3-31.4 mol%) (BCKN) salt and a MgCl2-KCl-NaCl (40-40-20 mol%) salt. BCKN salt was shown to have a similar melting temperature while having a higher heat capacity and far better oxidation resistance. </p> <p>The corrosion of the nickel-based superalloy Haynes 214 was studied in molten MgCl2-KCl-NaCl (40-40-20 mol%) salt at 750oC under inert atmosphere conditions using a custom-built rotating-disc corrosion testing apparatus that maintained laminar fluid flow on the sample. Non-protective external Cr-, Al-, and Mg- oxide layers were formed on Haynes 214 that were prone to spallation. Internal oxidation of Al was also observed along with Cr depletion zones within Haynes 214.  Corrosion kinetics were evaluated to quantify the role of fluid flow for application of this alloy for use in containment and transportation of this molten chloride salt. </p>

The global need to eliminate CO2 emissions and its consequent reduction in the use of fossil fuels drives the ongoing energy transition that highly involves the research achievements of the scientific community to reach the goals of this purpose. Renewable sources like photovoltaic and wind energy, are central to this endeavor, however, the intermittency of natural resources makes it non-dispatchable and energy storage is fundamental. According to the European Roadmap [1] just a 60% of the CO2 emissions reduction goal can be achieved with available technologies and existing energy. However, the production, use and specially storage opportunities that hydrogen offers can drive non-dispatchable renewable sources to achieve its full potential by clearing up the intermittency problem as well as covering the remained 40% gap. This master's thesis aims to investigate the techno-economic feasibility of integrating a Solid Oxide Electrolyzer Cell (SOEC) into a hybrid PV-CSP(sCO2) plant. The study focuses on assessing various indicators related to electricity, energy, and hydrogen production prices. To achieve this, three different integration strategies within the hybrid PV-CSP(sCO2) plant were selected for analysis: Soec using heat from the particles coming from the receiver, soec using heat coming from the particles available in the thermal energy storage (TES) and soec recovering heat from the sCO2 power block. A sensitivity analysis was conducted on different PV sizes (MWp), battery capacities (MWh), and SOEC installed capacities (MWh) to investigate the technology's potential in the plant and determine optimal sizing of subsystems. However, the individual optimization of economic indicators presented technical and economic challenges. Scenarios allowing individual optimization of hydrogen production prices (€/kg H2) resulted in 10.9, 11.7, and 14.6 €/kg h2 for receiver, TES, and sCO2 integration strategy, respectively. These scenarios, however, require high SOEC installed capacities, leading to elevated electricity and energy production prices. On the other hand, the individual optimization of electricity and energy production prices led to better and lower results when no hydrogen production presence within the plant. However, this analysis also showed that soec capacities below 5MWh together with no installation of batteries and a new definition for calculating hydrogen production prices (LCOH) allows feasible integration of hydrogen production within the plant. LCOH(€/kg h2) results were 10.2€/kg h2, 7.6€/kg h2, and 9.4€/kg h2 for receiver, TES, and sCO2, respectively, for a soec installed capacity of 0.5MWh (119m2 size) along with energy production values not exceeding 101€/MWh. While the results present a favorable outlook for SOEC installations based on literature review data [2] [3] [4] they still face challenges when competing with the cost-efficient PEM technology, which offers 4.5-5.5€/kg H2 [5] without storage. Nonetheless, this research contributes valuable insights into the integration of SOEC technology within hybrid renewable energy systems and provides a comprehensive analysis of the techno-economic aspects related to hydrogen production following different integration strategies. The findings may inform decision-making processes and promote further advancements in sustainable energy solutions. / Det globala behovet av att eliminera CO2utsläpp och därmed minska användningen av fossila bränslen driver pågående energiomställning, som starkt involverar forskningsresultaten från vetenskapssamhället för att nå syftet med detta mål. Förnybara källor som solceller och vindkraft är centrala i detta arbete, men intermittensen hos naturliga resurser gör dem icke disponibla och energilagring är grundläggande. Enligt den europeiska vägkartan [1] kan endast 60% av målet att minska CO2-utsläppen uppnås med tillgängliga teknologier och befintlig energi. Produktionen, användningen och särskilt lagringsmöjligheterna som väte erbjuder kan emellertid driva icke-disponibla förnybara källor att nå sin fulla potential genom att lösa intermitt ensproblemet och täcka den återstående 40% klyftan. Detta examensarbete syftar till att undersöka den tekniskekonomiska genomförbarheten av att integrera en fastoxid elektrolysör (SOEC) i en hybrid PV CSP(sCO2)-anläggning. Studien fokuserar på att utvärde ra olika indikatorer relaterade till el-, energi- och vätgasproduktionspriser. För att uppnå detta har tre olika integrationsstrategier inom hybrid PV CSP(sCO2) anläggningen valts för analys: SOEC med hjälp av värme från partiklar som kommer från mottagaren, SOEC med hjälp av värme från partiklar som finns i termisk energilagring (TES) och SOEC som återvinner värme från sCO2-kraftblocket. En känslighetsanalys har genomförts för olika PVstorlekar (MWp), batterikapaciteter (MWh) och SOEC installerade kapacit eter (MWh) för att undersöka teknologins potential i anläggningen och bestämma optimal dimensionering av delsystem. Resultaten från individuell optimering av ekonomiska indikatorer ledde dock till flera tekniska och ekonomiska utmaningar. Scenarier som tillåter individuell optimering av vätgasproduktionspriser (€/kg H2) resulterade i 10, 9, 11, 7 respektive 14,6 €/kg H2 för mottagare, TES och sCO2 integrationsstrategi. Dessa scenarier kräver dock höga SOEC installerade kapaciteter, vilket leder till höga el och energipriser. Å andra sidan ledde individuell optimering av el och energiproduktionspriser till bättre och lägre resultat när ingen vätgasproduktion fanns i anläggningen. Denna analys visade också att SOEC kapaciteter under 5MWh tillsammans med ingen installation av batterier och en ny definition för beräkning av vätgasproduktionspriser (LCOH) möjliggör genomförbar integration av vätgasproduktion i anläggningen. LCOH (€/kg H2) resultaten var 10,2 €/kg h2 , 7 ,6 €/kg h2 respektive 9,4 €/kg h2 för mottagare, TES och sCO2, för en SOEC installerad kapacitet på 0,5 MWh (storlek 119m2) tillsammans med energiproduktionsvärden som inte överstiger 101 €/MWh. Medan resultaten visar en gynnsam utsikt för SOECinstallationer baserat på data från litteraturöversikter [2] [3] [4], står de ändå inför utmaningar när de konkurrerar med den kostnadseffektiva PEM teknologin, som erbjuder 4,5-5,5 €/kg H2 [5] utan lagring. Trots detta bidrar forskningen med värdefulla insikter i integrationen av SOEC teknologi i hybrid förnybara energisystem och ger en omfattande an alys av de teknisk-ekonomiska aspekterna relaterade till vätgasproduktion enligt olika integrationsstrategier. Resultaten kan informera beslutsprocesser och främja ytterligare framsteg inom hållbara energilösningar.

When selecting a study abroad program, some students undertake a semester or academic-year study abroad program, while other students undertake a two-to eight-week study abroad program. Both study abroad opportunities allow students to become immersed in a culture different from their own. This research project is an exploratory study that looks at the impact of short-term study abroad programs on undergraduates at a public institution. This study examines how participants change in regards to their understanding of the host culture, explores what students learn about their host cultures, and looks at the intercultural development that the students gain from spending a short time abroad on an academic program. The people who participated in this research project are students from the University of Utah who spent time on a short-term (two to eight weeks) study abroad program. The literature reviewed in this study looks at number of articles that have been written about both short-term study abroad programs as well as long-term study abroad programs. The participants in this study came from a variety of academic backgrounds and class standings. A list was compiled of participants who indicated on their study abroad application that they did not have any previous international experience prior to their short-term study abroad experience. From this list, students were randomly emailed asking if they would like to participate on this study. This study revealed that individuals who participate in a short-term study abroad program do have transformative experiences. This study concluded that individuals who participate on short-term study abroad programs experienced personal growth as a result of studying abroad.