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A Construct Validation of the Neutral Objects Satisfaction Questionnaire (NOSQ)Eschleman, Kevin J. January 2008 (has links)
No description available.
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The Relationship Between Gender-Inclusive College Housing Environments and Students’ Sense of BelongingTodd, Dwayne 06 September 2016 (has links)
No description available.
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The effect of Trinexapac Ethyl and three Nitrogen sources on creeping bentgrass (<i>Agrostis stolonifera</i>) grown under three light environmentsNangle, Edward J. 19 March 2008 (has links)
No description available.
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Thesis - Optimizing Smooth Local Volatility Surfaces with Power Utility FunctionsSällberg, Gustav, Söderbäck, Pontus January 2015 (has links)
The master thesis is focused on how a local volatility surfaces can be extracted by optimization with respectto smoothness and price error. The pricing is based on utility based pricing, and developed to be set in arisk neutral pricing setting. The pricing is done in a discrete multinomial recombining tree, where the timeand price increments optionally can be equidistant. An interpolation algorithm is used if the option that shallbe priced is not matched in the tree discretization. Power utility functions are utilized, where the log-utilitypreference is especially studied, which coincides with the (Kelly) portfolio that systematically outperforms anyother portfolio. A fine resolution of the discretization is generally a property that is sought after, thus a seriesof derivations for the implementation are done to restrict the computational encumbrance and thus allow finer discretization. The thesis is mainly focused on the derivation of the method rather than finding optimal parameters thatgenerate the local volatility surfaces. The method has shown that smooth surfaces can be extracted, whichconsider market prices. However, due to lacking available interest and dividend data, the pricing error increasessymmetrically for longer option maturities. However, the method shows exponential convergence and robustnessto different initial (flat) volatilities for the optimization initiation. Given an optimal smooth local volatility surface, an arbitrary payoff function can then be used to price thecorresponding option, which could be path-dependent, such as barrier options. However, only vanilla optionswill be considered in this thesis. Finally, we find that the developed
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Hur kan man ersätta traditionellt portlandcement som bindemedel i betong? / How to replace traditional portland cement as a binder in concrete?Bjerhag, Otto, Kassab, Abdulatif January 2022 (has links)
Concrete manufacturers claim that using substitute like blast furnace slag, fly ash and silica reduces the climate impact when used as a substitute for cement. Reducing climate emissions is an important topic for companies that currently produce concrete to achieve a sustainable society. The results have been collected by conducting interviews withexperts and sending out a questionnaire survey to concrete companies as well as some assessment through possible calculations that are linked to the survey results. The purpose of the survey is to find out the different substitutes used in Sweden and which substitutes may be conceivable for the future and to assess the development work for these different substitutes. The study shall provide relevant information about these different substitutes and show what effects are brought to the climate when the substitutes are used. The aim of the study is to increase understanding of current and future concrete and how these various substitutes can be useful in the future in the manufacture of concrete. Blast furnace slag, fly ash and silica are three different substitutes used as substitutes for cement. The most common substitute that is available and useful in Sweden is blast furnace slag, which means less climate impact. Conclusions drawn by the study are that these various substitutes contribute to reduced climate impact when used with cement and that substitutes are a temporary solution, meanwhile the real problem is to find new products as alternatives to limestone in cement production.
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Environmentally improved concrete is compared with ordinary concrete with respect to estimated environmental impact / Miljöförbättrad betong jämförs med vanlig betong med avseende på beräknad miljöpåverkanAlzuhairi, Fatin, Fatah, abdulfata January 2020 (has links)
Swedish buildings account for a large part of Sweden's greenhouse gas emissions, which is why the construction industry within the framework of the concrete initiative has produced a Roadmap for Climate Neutral Concrete. The climate neutral targets meant that Sweden will have net carbon emissions of carbon dioxide in the atmosphere by 2045. In order to achieve the national environmental goals, it is important to reduce the climate impact from concrete construction. Today, the concrete industry is facing a major challenge in minimizing the consumption of concrete, while at the same time the need for new buildings is increasing as a result of the increase in land populations.Concrete lifecycle analysis shows that 90 percent of carbon dioxide emissions come from the manufacturing process of cement clinker that is included in the cement binder. For this reason, the concrete industry has researched and developed various alternatives that contribute to reducing the environmental impact caused by concrete by reducing carbon dioxide emissions.The purpose of this thesis is to evaluate the environmental impact of different types of concrete and to investigate two factors that contribute to reducing carbon dioxide emissions in the atmosphere. The factors being investigated are choice of optimized concrete recipe by reducing proportion of cement and choice of concrete composition by replacing cement with alternative binders.A survey study was conducted to analyze the environmental impact of different types of concrete with different amounts of cement, water percentage and exposure class. In addition, a comparison study between ordinary concrete and climate-enhanced concrete was performed to analyze the climate impact of climate-enhanced concrete with different improvement steps compared to ordinary concrete. To carry out this study, a study of ordinary concrete has been carried out with documents (concrete quantity, strength class and water cement figures) from a reference project obtained by Specialfastigheter, and then replaced with climate-enhanced concrete in various improvement steps.The results show that concrete with lower cement volume and higher water cement numbers give a marked reduction in the building's climate impact. By reducing the amount of cement in the concrete, the proportion of cement clinkers included in the cement binder is lowered, which in turn reduces the climate impact. In addition, a comparison study also shows that the building's climate impact can be reduced between 10, 25 and 52 percent through the use of climate-enhanced charm. This is because climate-enhanced concrete is being replaced by some cement with alternative binders.The conclusion is that this study provides greater opportunity for the construction industry to gain additional knowledge and a better understanding of how environmental impact can be reduced by choosing the right type of concrete. Choosing concrete with lower strength, higher water cement ratio and higher proportion of alternative binders contributes to lower climate impact from concrete. / Svenska byggnader står till svars för en stor del av Sveriges utsläpp av växthusgaser, därför har byggbranschen inom ramen för betonginitiativet tagit fram Färdplan för Klimatneutral betong. Klimatneutralmålen innebär att Sverige ska uppnå nettonollutsläpp av koldioxid i atmosfär år 2045. För att kunna nå de nationella miljömålen är det viktigt att sänka klimatpåverkan från betongkonstruktion. Idag befinner sig betongbranschen inför stor utmaning att minimera konsumtion av betong, samtidigt som behovet av nybebyggelse ökar till följd av att jordbefolkningen ökar.Betonglivscykelanalys visar att 90 procent av koldioxidutsläpp kommer från tillverkningsprocess av cementklinker som ingår i bindemedlet cement. Av denna anledning har betongbranschen undersökt och utvecklat olika alternativ som bidrar till minskning av miljöpåverkan orsakad av betong genom att reducera koldioxidutsläpp.Syftet med detta examensarbete är att utvärdera miljöpåverkan från olika betongssorter samt att undersöka två faktorer som bidrar till minskning av koldioxidutsläpp i atmosfären. De faktorer som ska undersökas är val av optimerat betongsrecept och alternativa bindemedel. Det optimerade betongrecept sker genom minskning av andel av cement och val av betongsammansättning där cement ersätts med alternativa bindemedel.En undersökningsstudie utfördes för att analysera miljöpåverkan av olika betongssorter med olika cementsmängd, vattencementtal och exponeringsklass. Dessutom utfördes en jämförelsestudie mellan vanlig betong och klimatförbättrad betong för att analysera klimatpåverkan av klimatförbättrad betong med olika förbättringssteg jämfört med vanlig betong. För att genomföra denna studie har olika betongsmängder, hållfasthetsklass och vattencementtal undersökas. Betonginformation hämtas från ett referensprojekt erhållna av Specialfastigheter för att sedan ersättas med klimatförbättrad betong i olika förbättringssteg.Resultaten visar att betong med lägre cementmängd och högre vattencementtal ger uppmärksammade minskning av byggnadens klimatpåverkan. Genom att minska cementmängden i betongen sänks andelen av cementklinker som ingår i bindemedlet cement, vilket i sin minskar klimatpåverkan. Dessutom visar även jämförelsestudien att byggnadens klimatpåverkan kan minskas mellan 10, 25 och 52 procent genom användning av klimatförbättrad betog. Detta beror på att klimatförbättrad betong ersätter en del av cement med alternativa bindemedel.Slutsatsen är att denna studie ger större möjlighet för byggbranschen att få ytterligare kunskap samt bättre förståelse om hur miljöpåverkning kan minskas genom att välja rätt betongtyp. Att välja betong med lägre hållfasthet, högre vattencementtal och högre andel av alternativa bindemedel bidrar till lägre klimatpåverkan från betong.
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Investigating Impact of Emerging Medium-Voltage SiC MOSFETs on Medium-Voltage High-Power ApplicationsMarzoughi, Alinaghi 16 January 2018 (has links)
For decades, the Silicon-based semiconductors have been the solution for power electronics applications. However, these semiconductors have approached their limits of operation in blocking voltage, working temperature and switching frequency. Due to material superiority, the relatively-new wide-bandgap semiconductors such as Silicon-Carbide (SiC) MOSFETs enable higher voltages, switching frequencies and operating temperatures when compared to Silicon technology, resulting in improved converter specifications. The current study tries to investigate the impact of emerging medium-voltage SiC MOSFETs on industrial motor drive application, where over a quarter of the total electricity in the world is being consumed.
Firstly, non-commercial SiC MOSFETs at 3.3 kV and 400 A rating are characterized to enable converter design and simulation based on them. In order to feature the best performance out of the devices under test, an intelligent high-performance gate driver is designed embedding required functionalities and protections. Secondly, total of three converters are targeted for industrial motor drive application at medium-voltage and high-power range. For this purpose the cascaded H-bridge, the modular multilevel converter and the 5-L active neutral point clamped converters are designed at 4.16-, 6.9- and 13.8 kV voltage ratings and 3- and 5 MVA power ratings. Selection of different voltage and power levels is done to elucidate variation of different parameters within the converters versus operating point.
Later, comparisons are done between the surveyed topologies designed at different operating points based on Si IGBTs and SiC MOSFETs. The comparison includes different aspects such as efficiency, power density, semiconductor utilization, energy stored in converter structure, fault containment, low-speed operation capability and parts count (for a measure of reliability). Having the comparisons done based on simulation data, an H-bridge cell is implemented using 3.3 kV 400 A SiC MOSFETs to evaluate validity of the conducted simulations.
Finally, a novel method is proposed for series-connecting individual SiC MOSFETs to reach higher voltage devices. Considering the fact that currently the SiC MOSFETs are not commercially available at voltages higher above 1.7 kV, this will enable implementation of converters using medium-voltage SiC MOSFETs that are achieved by stacking commercially-available 1.7 kV MOSFETs. The proposed method is specifically developed for SiC MOSFETs with high dv/dt rates, while majority of the existing solutions could only work merely with slow Si-based semiconductors. / Ph. D. / Despite their mature technology and low manufacturing cost, the traditional Si-based power semiconductors had reached their limitations in operation from different points of view. The SiC MOSFETs which are the new generation of power semiconductors however seem to be able to shift the existing boundaries of operation for the Si-based semiconductors, resulting in significant improvement in design and operation of power electronics converters. This dissertation focuses on investigating the impact of emerging medium-voltage SiC MOSFETs on industrial motor drives, which consume over 28% of the total electricity used in the world.
Firstly, the state-of-the-art non-commercial 3.3 kV SiC MOSFETs are characterized. Characterization of the devices is done to extract their key features such as switching and conduction losses, to enable loss calculation and performance evaluation in any target application. Since the mentioned devices are not commercial yet, the gate driving circuitry that can feature the best performance out of them are not commercially available either. Thus, the characterization process starts with design of an intelligent high-performance gate driver for the devices under test. Secondly, total of three topologies that are targeted for the study are discussed and their basics of operation is investigated. For this purpose the cascaded H-bridge, the modular multilevel converter and the 5-L active neutral point clamped converters are designed at three different voltage levels (4.16-, 6.9- and 13.8 kV) and two power levels (3- and 5 MVA). Selection of different voltage and power levels is done to enable comparison from different aspects as the operating point changes.
Later, comparisons are done between the surveyed topologies designed at different operating points using different semiconductor technologies. The performed comparisons provide an unbiased input for the manufacturers and customers of these converters for selection of the target topology in motor drive application. Also to verify validity of the conducted simulations and calculations, a full-bridge converter cell is experimentally implemented using 3.3 kV 400 A SiC MOSFETs.
Finally, a novel method is proposed for series-connecting lower-voltage SiC MOSFETs to reach higher-voltage devices. As of late 2017, the medium-voltage SiC MOSFETs are not commercially available. Also it is expected that upon commercialization, their price will be multiple times of that of low-voltage SiC MOSFETs. Thus, connecting lower-voltage SiC MOSFETs in series is an effective way of achieving higher-voltage devices and take advantage of superior properties if the SiC MOSFETs, while the availability and high cost problems are taken care of.
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Röstinstrument eller idiom? : Att bygga ett genreöverskridande instrumentMalm, Karin January 2024 (has links)
Under de senaste 400 åren har röstorganet inte genomgått någon utmärkande fysiologisk förändring, men under samma tidsspann har musikaliska förgreningar lett till en ständigt ökande mängd nya genreuttryck. Som genrebred sångerska har jag ofta uppmuntrats att välja inriktning. Det har helt gått emot min nyfikenhet och intuition. Jag har bedrivit studier i populärmusikalisk sång vid Berklee College of Music i Boston, USA, och klassisk sång vid Kungl. Musikhögskolan (KMH) i Stockholm. Jag har noterat att rösten ofta blir uppdelad i antingen en klassisk röst eller en populärmusikalisk röst. Syftet med detta konstnärliga examensarbete var att undersöka genreoberoende sångteknik och därigenom skapa djupare förståelse för samverkan mellan olika genreuttryck inom instrumentet sång. Jag ville undersöka om en och samma röst kan implementera olika genrer och till och med gynnas av det. På min examenskonsert framfördes en varierad repertoar, med musik av Bernstein, Mozart och Offenbach samt sånger ur Kristina från Duvemåla och egenkomponerat material. Studien genomfördes metodiskt genom litteraturstudier samt kvalitativa intervjuer med tre sakkunniga informanter; en sångpedagog, en röstforskare och en logoped. Vidare har jag utfört undersökningar med min egen röst. Studien har resulterat i en förstärkt övertygelse om den genreoberoende sångteknikens fördelar. Sångare kan ha god nytta av den flexibilitet som en sådan teknik innebär, för att bygga en hälsosam och gedigen röst. Min utgångspunkt var att undersöka rösten som ett instrument eller ett idiom. Studiens resultat påvisar att rösten bör ses som det förstnämnda. / Throughout the last four centuries, the vocal organ has not undergone any significant physiological evolution. Yet during the same time span, the musical diaspora has led to an increasing amount of new genre expressions. As a genre-bending singer, I have often been encouraged to choose musical orientation. That has been contradictory to my curiosity and intuition. I have studied contemporary singing at the Berklee College of Music in Boston, USA, and classical singing at the Royal College of Music in Stockholm, Sweden. I have noted that contemporary singing and classical singing are often viewed as two different doctrines. The purpose of this artistic research study was to explore genre-neutral and genre-bending vocal techniques in order to enhance my understanding of the relationship between different genre expressions, within the vocal instrument. I wanted to examine if one voice could implement different genres, or even benefit from it. At my graduation concert, I performed a varied repertoire consisting of music by Bernstein, Mozart and Offenbach as well as songs from Kristina from Duvemåla and self-composed pieces. The study was conducted methodically through academic literature and qualitative interviews with three experts; a vocal coach, a voice researcher, and a speech therapist. Furthermore, I have conducted research on my own voice. This study has resulted in a reinforced belief in the benefits of the genre-neutral and genre-bending vocal technique. Singers can benefit from the flexibility that such a technique amounts to, in order to build a healthy and solid voice. My objective was to analyze the voice as an instrument or an idiom. This study concludes that it should be viewed as the former.
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Transition to Carbon-Neutral Campuses : Scenario Evaluation and Selection Including Human-Centric PerspectiveShi, Zhirong January 2024 (has links)
The urgent need to combat climate change is increasingly being recognized. The Paris Agreement, which aims to limit global warming, requires carbon neutrality to be achieved by the mid-21st century. Further, the energy crisis in Europe that started in 2021 highlights the importance of energy security. Universities play a crucial role in promoting the transition to neutrality. This study aims to increase universities' electricity independence to further facilitate their transition to carbon neutrality. To this end, a multi-criteria decision analysis (MCDA) method was adopted to select scenarios for increasing a campus building complex's electricity independence, considering various stakeholders' interests together with the scenarios' performances on technical, environmental, economic, and social criteria. The findings show that photovoltaic technology, despite its perceived environmental benefits, performs poorly in reducing carbon emissions when considering lifecycle emissions, particularly in countries with low-carbon electricity like Sweden. Conversely, energy conservation through behavioral changes emerges as the optimal scenario for Campus Gotland due to its economic and environmental advantages. These results challenge the common reliance on energy production technology for carbon neutrality, highlighting the greater effectiveness of demand-side measures. This work suggests that universities need a more human-centric approach to transitioning to carbon neutrality. In a broader context, this study provides universities with insights to make informed decisions to achieve carbon neutrality, emphasizing the need to consider all stakeholders. By offering a comprehensive assessment and analysis of various scenarios, this work enhances the understanding of best practices for universities aiming to lead in the global effort against climate change.
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Live Load Testing and Analysis of the Southbound Span of U.S. Route 15 over Interstate-66Collins, William Norfleet 25 August 2010 (has links)
more funding must be allocated for their rehabilitation or replacement. The Federal Highway Administration's (FHWA) Long-Term Bridge Performance (LTBP) Program has been developed to help bridge stakeholders make the best decisions concerning the allocation of these funds. This is done through the use of high quality data obtained through numerous testing processes.
As part of the LTBP Pilot Program, researchers have performed live load tests on the U.S. Route 15 Southbound bridge over Interstate-66. The main performance and behavior characteristics focused on are service strain and deflection, wheel load distribution, dynamic load allowance, and rotational behavior of bridge bearings.
Data from this test will be used as a tool in developing and refining a plan for long-term bridge monitoring. This includes identifying the primarily loaded girders and their expected range of response under ambient traffic conditions. Information obtained from this test will also aid in the refinement of finite element models by offering insight into the performance of individual bridge components, as well as overall global behavior. Finally, the methods and results of this test have been documented to allow for comparison with future testing of this bridge, which will yield information concerning the changes in bridge behavior over time. / Master of Science
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