Many portions of energy generated in the U.S. are not used and take the form of wasted heat due to a poor heat transfer efficiency. This fact leads research communities to focus on thermoelectrics as a means for using waste heat through direct thermal to electrical energy conversion. One way to enhance thermoelectric efficiency is to reduce thermal conductivity through nanostructuring. In nanostructures, understanding energy transport across the interface of two materials is important because interfaces dominate the resistance to overall thermal transport of the system and can be described by thermal boundary conductance (TBC). Also of note, an understanding of thermal transport cannot be achieved without an understanding of transfer via atomic vibration, known as phonons. In this study, two different techniques of molecular dynamics (MD) simulation are introduced in order to improve the understanding of the phonon transport at the interface of dissimilar materials and the impact of different material properties on TBC. Non-equilibrium MD simulations are used to study relative and combined contributions of mass and bond energy difference on TBC and phonon wave-packet simulations are used to obtain a detailed description of phonon interactions at the interface. At the end of this study, a simple analytical model for the prediction of effective thermal conductivity, using knowledge of thermal boundary resistance, an inverse of TBC, and the interface geometry, is developed.

Denna Kandidatuppsats kommer ta upp det ständigt växande fenomenet massturism och hur den påverkar turister både när de är ute och reser och i deras vardagliga liv. För att få en generell bild av hur fenomenet påverkar turister har vi gjort en enkätundersökning som besvarats av ett hundratal personer som fått beskriva om och hur de upplevt massturism. För att få en djupare förståelse av hur massturism påverkar en destination specifikt har intervjuer utförts med tio personer som alla besökt Venedig, som är staden som vi har utfört en fallstudie om. I inledningen presenters och förklaras massturism. I metod och teori förklaras de metoder som kommer att användas samt en förklaring varför vi tror att de passar vår undersökning. Tidigare forskning tar upp forskning som redan gjorts om massturism generellt och massturismen i Venedig. I ramverk för fortsatt forskning förklaras de begrepp som sedan analyserats i resultat. I resultatet kommer empirin läggas fram och analyseras utifrån vår enkätundersökning och intervjuer. Diskussionskapitlet diskuterar våra resultat för att slutligen leda fram till vår slutsats. Våra frågeställningar har varit: På vilka sätt anser turister generellt att massturismen har påverkat deras besök på en destination? Och Hur upplever besökare i Venedig dess massturism och på vilket sätt har fenomenet påverkat deras besök? / This bachelor thesis will present the ever-growing phenomenon, mass tourism and what impact it has on tourists when they are traveling and in their everyday life. To get a general picture of how the phenomenon affects tourists, we have done a survey answered by a hundred people who got to describe whether and how they experienced mass tourism. To get a better understanding of how mass tourism affects a specific destination, we have made interviews with ten people who all visited Venice, which is the city that we have made a case study about. In the introductory part we will present mass tourism and explain the phenomenon. In the methodology part, we explain the methods we will use and why we think they fit our thesis. Previous research includes research already done about mass tourism in general and mass tourism in Venice. In the framework for further research, we will explain the concepts which we then are going to analyse our results from. In the result, we present and analyse the empirical findings that we have collected through our survey and interviews. The discussion part will discuss our results and ultimately lead to our conclusion. Our research questions are: In what way do tourists generally think that mass tourism have affected their visits to a destination? And How do visitors in Venice see its mass tourism and in what way does the phenomenon affect their visit?