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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

A decision analysis of an oil company's retail strategy in the face of electric vehicle penetration uncertainty

Jo, Dohyun 19 July 2012 (has links)
This thesis evaluates emerging electric vehicle technology and estimates what effect it might have on how an oil company decides on its gas station network. It is conducted using data from South Korea, a country poised for a fast adoption of electric vehicles. The study first reviews the literature to gather reasonable cases of electric vehicle penetration. Also, after researching technology-diffusion theories, the study selects a model that can well explain the literature review data. The scenarios induced by this function are utilized as the main uncertainties confronting an oil company’s network decision model. Based on a probabilistic simulation, the study finds that the effects of technology diffusion alter the priority order of an oil company’s network decision alternatives. Namely, after the overall uncertainty level rises, directly owning gas station, with its heavy initial investment, is not preferred for an oil company’s network strategy. From the result, the study also estimates the scale of the new technology’s effect. Such effect is found to be significant enough to alter a part of an oil company’s retail strategy. Nevertheless, such effect cannot be shown to be so great as to change the current retail oil market structures. / text
62

Impact of range anxiety on driver route choices using a panel-integrated choice latent variable model

Chaudhary, Ankita 02 February 2015 (has links)
There has been a significant increase in private vehicle ownership in the last decade leading to substantial increase in air pollution, depleting fuel reserves, etc. One of the alternatives known as battery operated electric vehicles (BEVs) has the potential to reduce carbon footprints due to lesser or no emissions and thus the focus on shifting people from gasoline operated vehicles (GVs) to BEVs has increased considerably recently. However, BEVs have a limited ‘range’ and takes considerable time to completely recharge its battery. In addition, charging stations are not as pervasive as gasoline stations. As a result a new fear of getting stranded is observed in BEV drivers, known as range anxiety. Range anxiety has the potential to substantially affect the route choice of a BEV user. It has also been a major cause of lower market shares of BEVs. Range anxiety is a latent feeling which cannot be measured directly. It is not homogenous either and varies among different socio-economic groups. Thus, a better understanding of BEV users’ behavior may shed light on some potential solutions that can then be used to improve their market shares and help in developing new network models which can realistically capture effects of varying EV adoptions. Thus, in this study, we analyze the factors that may impact BEV users’ range anxiety in addition to their route choice behavior using the integrated choice latent variable model (ICLV) proposed by Bhat and Dubey (2014). Our results indicate that an individual’s range anxiety is significantly affected by their age, gender, income, awareness of charging stations, BEV ownership and other category vehicle ownership. Further, it also highlights the importance of including disutility caused by distance while considering network flow models with combined GV and BEV assignment. Finally, a more concentrated effort can be directed towards increasing the awareness of charging station locations in the neighborhood to help reduce the psychological barrier associated with range anxiety. Overcoming this barrier may help increase consumer confidence, resulting in increased BEV adoption and ultimately will lead towards a potentially pollution-free environment. / text
63

La Evaluación Formativa en la Enxeñanza-Aprendizaje del Inglés.

Zambrano Rujano, Gabina Elisabeth 08 June 2006 (has links)
Educar es una tarea compleja que exige un trabajo constante y sistemático, además de una vocación esencial para ir superando los obstáculos que se nos presentan a diario y dada la naturaleza del proceso de evaluación del aprendizaje, en nuestro caso la adquisición de Inglés en el contexto de lengua extranjera (EFL), parece lógico pensar que ello requiere que, por un lado, el profesor posea un posicionamiento pedagógico y un conocimiento de la materia que enseña y de su estructura interna y, por otro, que exista una planificación y programación para dar respuesta a los interrogantes: ¿qué, cómo y cuándo enseñar y evaluar? Igualmente, es importante que el profesor asuma un enfoque multivariado hacia la enseñanza- aprendizaje y evaluación para promover la apropiación de hechos, conceptos, principios, procesos, valores y actitudes en congruencia con un proceso evaluativo que permite a los alumnos expresar sus percepciones, opiniones, sentimientos sobre su aprendizaje, el desarrollo del programa y el desenvolvimiento del profesor desde un enfoque formativo complementado con un enfoque formador. Con este planteamiento en mente se elaboró un marco teórico donde se indagaron las propuestas actuales de la evaluación de programas, la evaluación del aprendizaje y la evaluación del aprendizaje de Inglés. Todo ello bajo una metodología centrada en la mejora de la cultura de evaluación formativa del Área de Inglés de la Universidad de Los Andes Táchira a través de una fase diagnóstica y una intervención dirigida a la mejora de los programas, la sensibilización del profesorado y la aplicación de un modelo de evaluación formativa. Los resultados nos llevaron a concluir que el programa constituye el punto de referencia de la práctica docente y que la evaluación formativa conduce al aprendizaje significativo del alumno y del profesor. / Teaching is a complex activity which demands a constant and systematic process and an essential vocation to overcome the obstacles that arise daily and due to the nature of the assessment process, in our case English as a foreign language (EFL), it seems logical to think that it conveys an educational posture and a practical and methodological approach by the teacher as well as a knowledge of the subject he is teaching, altogether with a syllabus that can answer the questions of what, how and when to teach and to assess? At the same time, if the teacher assumes a multivariate theoretical, practical and pragmatic posture towards evaluation through the appropriation of facts, concepts, principles, procedures, algorithms, etc. combined with the sensibility to let students express their perceptions, feelings and opinions about his learning process, the syllabus, and the methodology of the teacher from on a formative approach, an interesting combination arises that promotes personal and professional growth. With these principles in mind, the theoretical framework was based on the syllabus design, the assessment of the teaching-learning process, and the assessment of the English language learning. The methodology involved the improvement of the culture of formative assessment of the English Area in the Language Department of the Universidad de Los Andes Táchira through a diagnostic phase and a proposal to improve the syllabuses, induce teacher reflection and develop a formative approach to English assessment in the English classroom. It was concluded that the syllabus is the point of reference to the educational process and that formative assessment induces meaningful learning of the student and the teacher.
64

Development of circulatory microRNAs as markers of organ injury and mediators of inter-organ signalling

Morrison, Emma Elisabeth January 2018 (has links)
Plasma contains small, non-protein coding RNA species, microRNAs (miRNAs). Circulating miRNAs originate from tissues throughout the body and circulate in the blood bound to proteins or encapsulated in extracellular vesicles (EVs). The pattern of circulating miRNAs changes in different pathological states, leading to the hypothesis that they could act as biomarkers or mediators of inter-organ signalling. Acute kidney injury (AKI) is associated with high morbidity worldwide. Recent work has highlighted a potential role for EV signalling in the delivery of functional exogenous miRNA into kidney cells, which may contribute to the pathogenesis of AKI. The studies described in this thesis investigate the effects of circulating miRNAs on renal proximal tubular (PT) cells. Utilising next generation sequencing technology, circulating miRNA profiles were demonstrated to change significantly following myocardial injury. These findings were translated from humans into a mouse model of myocardial injury. Investigation of EV cell signalling, using flow cytometry and nanoparticle tracking analysis, demonstrated that PT cell EV uptake was not affected by known physiological agonists. By contrast, EV release from PT cells was regulated by purinergic P2Y1 and dopamine D1 receptors. Toxic cisplatin injury of PT cells resulted in increased EV release and reduced EV uptake in a dose-dependent manner. Cisplatin toxicity in PT cells was unaffected by EVs from mice with myocardial injury, but toxicity was reduced by EVs from mice with drug-induced liver injury (DILI). Circulating EVs from mice with DILI transferred the liver specific miRNA, miR-122, into PT cells in both in vivo and in vitro models. The consequence of miR-122 transfer was modulation of downstream target genes including Foxo3 which has been implicated in cell injury by apoptosis. These findings therefore show that circulatory miRNA profiles change in different models of organ injury and suggest miRNAs can be transferred to PT cells in vivo and in vitro. The improved viability of injured PT cells following co-incubation with DILI EVs, and subsequent transcriptomic work, suggests this may be as a consequence of miRNA transfer. In conclusion, circulatory miRNAs may act as mediators of inter-organ signalling and could play a crucial role in the propagation of systemic illness.
65

Mekanisk strategi på den nordiska aktiemarknaden : En kvantitativ studie där kombinationer av värdeaktier och momentum utreds

Anundsson, Johan, Nordqvist, Anna January 2018 (has links)
Debatten kring huruvida det är möjligt att överavkasta aktiemarknaden över tid har existerat i många år. Forskare som Eugene Fama (1965) konkluderar att aktiemarknader i allmänhet är effektiva och menar att högre avkastning inte kan genereras utan ökat risktagande. Andra forskare som exempelvis Shiller (2003) har dock dragit slutsatsen att det finns investeringsstrategier som överavkastar marknaden över tid. Denna studie syftar till att undersöka effektiviteten på den nordiska aktiemarknaden genom att utvärdera prestationen av olika portföljer sammansatta av utvalda nyckeltal. Vidare utreder författarna huruvida valet av beräkningsmodell påverkar bedömningen av portföljernas prestationer.   Studien utreder samtliga kombinationer av variablerna EV/S, EV/EBIT och momentum. De första två nyckeltalen beaktar bolagets värde (EV) i relation till dess försäljning (S) respektive vinst (EBIT). Den tredje variabeln som undersöks i studien är momentum, vilket är en indikator som används för att finna de aktier som ökat mest i pris den senaste tiden. Tidigare forskning visar att kombinationen av värdeaktier (exempelvis EV/S och EV/EBIT) och momentum kan generera överavkastning tack vare en negativ korrelation mellan variablerna. För att utreda hur samtliga kombinationer presterar så skapas portföljer sammansatta av de olika nyckeltalen. Studien undersöker hur portföljerna presterar över en tioårsperiod på den nordiska aktiemarknaden. Portföljerna utvärderas med hjälp av tre olika teoretiska beräkningsmodeller som alla är vedertagna inom anomali-forskningen. Capital Asset Pricing Model (CAPM) skattar portföljers avkastning baserat på den tagna risken, trefaktormodellen inkluderar även proportionen småbolag och andelen värdeaktier medan fyrfaktormodellen inkorporerar momentum som en ytterligare faktor.     Studien resulterar i att fem av de totalt sju portföljerna genererar en riskjusterad avkastning som skiljer sig från marknaden. Författarna kan konkludera att tre av dessa överavkastar marknaden medan två uppvisar en lägre riskjusterad avkastning än index. Portföljer innehållandes nyckeltalet EV/S presterar generellt sett undermåligt medan EV/EBIT ingår i flertalet framgångsrika portföljer.  Författarna kan se tendenser till att kombinationer av värdenyckeltal genererar extra värde samt att momentum i kombination med värdenycketal verkar vara fördelaktigt. De sistnämnda slutsatserna kan dock inte statistiskt säkerställas eftersom ingen av de undersökta kombinationerna var signifikant bättre än beståndsdelarna separat. Beroende på vilken av CAPM, trefaktormodellen eller fyrfaktormodellen som används för att skatta portföljernas prestationer varierar antalet signifikanta överpresterande portföljer. Författarna drar därav slutsatsen att det är viktigt att betänka valet av vilken beräkningsmodell som bör tillämpas för att skatta portföljernas riskjusterade avkastning.
66

Effect of Recycled Concrete Aggregate Properties on the Behaviour of New Concrete

Ahimoghadam, Faraz 04 May 2018 (has links)
Application of recycled concrete aggregates (RCA) has increased recently as a sustainable alternative in concrete construction. Although application of RCA has substantially grown over the past decades, issues related to its structural performance and long-term behaviour still prevent its widespread application, especially in structural purposes. In this study, a new mixture proportioning method called the “Equivalent Volume (EV)” method is proposed for RCA concrete, which is developed on the assumption that the RCA mix is based on a companion conventional concrete mix having the same volume of “cement paste and aggregates” as the companion mixture. RCA mixes containing different aggregate types and mechanical properties were designed using the EV method. Chemical, mechanical and non-destructive tests were performed and their performance was investigated. Finally, a quality control protocol for evaluating the suitability of RCA sources for structural applications is proposed. Results show that the EV method seems a promising approach to mix-proportion eco-friendly recycled concrete mixes. Moreover, the RCA type and properties seem to influence in the behaviour of RCA concrete and thus should be accounted in the mix- design.
67

Förhindra långvariga trafikstopp i spårväxlar med rörlig korsning

Svenningsson, Johan January 2017 (has links)
Purpose:The purpose of this study as a part of Trafikverkets continues improvement work is to create ahigher society value with less delayed train traffic. This study will analyze if it’stechnical/administrative possible to eliminate or reduce the delays which accrue when switcheswith swing nose crossing is not in control. The issue has been segmented in three sub issues:1. How does a switch with swing nose crossing work and which factors leads to a stop intraffic?2. What knowledge does train engineer have and how do they work today?3. Is it possible to change the current regulation without decrease the safety?Methodology:Literature study, interview and observation has been performed to see which issues switcheshas and what underlying effects that causes them. A workshop has been held with teacher andstudents in a school for train engineer. Collected data has been analyzed for compilation of thestudies result.Findings:As the regulation is written today it creates a complete stop in traffic when a switch with swingnose crossing goes in control. The studies result shows that train engineers has anunderstanding of the how switches with swing nose crossing works and therefore could it bepossible to alter the regulation. A change in this regulation could mean less delayed traintraffic. But also a greater risk for more collision between train and switches which could lead tothat more switches have to be repaired. A standardized approach in how to control a switchcould decrease this risk.Implications:The purpose of this study through the problem definition is deemed answered. Theunderstanding on the train engineer awareness of switches with swing nose crossing and theirdemands has been a great significance for the development work. More interviews andworkshops would have enhanced the scientific result.Recommendation:I advocate for a change in the regulation so that train engineer are allowed to pass a switch with swingnose crossing even if it’s not in control. There is also of great weight to study the back laying reasonsfor why train engineer misjudge switches position and why the switches doesn’t go in control.
68

Svenska körvanors påverkan på elnätet vid en elektrifiering av Sveriges fordonsflotta / A case study of the impact on the Swedish electricity grid, based on the full implementation of electric vehicles and our driving habits in consideration

Macklin, Christoffer January 2020 (has links)
Detta examensarbete har till uppgift att ta reda på hur det svenska elnätet påverkas av svenska körvanor vid en komplett omställning till eldrivna fordon. Genom att använda ett tidigare skapat simuleringsprogram byggt för att simulera elektriska parametrar i ett svenskt bostadsområde, är uppgiften i detta examensarbete att ta reda på ifall det nuvarande elnätet är robust nog att förse en fullt utvecklad el-baserad fordonsflotta med tillräcklig elektricitet. Elnätet som simuleras i detta examensarbete bygger på verkliga data från ett bostadsområde som tillhandahållits av Tekniska verken, där data består av effektuttag per timme över en period som täcker ett helt år.  Simuleringsstudien är genomförd baserad på elkonsumtionsdata från hushållen i ett bostadsområde, effektkonsumtion från ett flertal elbilsmodeller och fabrikat, fordonsfördelning baserat på hushållens köpkraft och statistik om svenska körvanor. Simuleringsstudien använder det tidigare skapta simuleringsmiljön för att simulera de effekter som uppstår vid elbilsladdning från multipla hushåll och varierande arbetstider.  I denna studie undersöks hur körvanor kommer påverka spänningsnivåerna i det lokala elnätet där ett antal fall undersökts. Dessa fall är: Varierande dagliga körsträckor, olika huvudsäkringar på hushållen och varierande arbetstider. Baserat på resultaten av de gjorda simuleringarna kan man dra slutsatsen att det nuvarande elnätet inte är robust nog att hantera en total utbyggnad av en el-baserad fordonsflotta. Det borde vara i elnätsägarnas intresse att studera detta betydligt noggrannare för att undvika problem i framtiden.
69

Implementation of highly sensitive small extracellular vesicle (sEV) quantification method in the identification of novel sEV production modulators and the evaluation of sEV pharmacokinetics / 高感度定量法を利用した細胞外小胞の産生モジュレーターの探索と体内動態解析

Yamamoto, Aki 24 September 2021 (has links)
京都大学 / 新制・課程博士 / 博士(薬学) / 甲第23473号 / 薬博第849号 / 新制||薬||242(附属図書館) / 京都大学大学院薬学研究科薬学専攻 / (主査)教授 髙倉 喜信, 教授 山下 富義, 教授 小野 正博 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM
70

Návrh podvozku pro elektrický minibus / Design of chassis for an electric minibus

Strnadel, Bronislav January 2019 (has links)
The theoretical part of the master thesis is devoted to electric vehicles from their history through sources of electric energy and a swapping battery system to electric buses and autonomous driving. In the practical part the concept of autonomous electric minibus with the calculation of battery capacity are described. Furthermore, the attachment of battery to chassis and the idea of automatic swap are designed. In the last chapter the design of chassis itself can be found together with the FEM analysis.

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