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I samband med att teknologin har utvecklats, har också vår förmåga att observera mindre och mindre objekt utvecklats. Detta är för att partiklar kan accelereras till högre och högre fart och därmed till högre energier. Utforskningen av hadroner, med partikelacceleratorer som Large Hadron Collider (LHC), har givit forskare en djupare förståelse om hur kvantkromodynamik (QCD), en av lärorna om materIn this thesis, the information loss from the modified Mass-Drop tagging of a Z to qqbar jet is studied for a pp collision at LHC centre-of-mass energies in PYTHIA 8 using FastJet 3. The jet created by the Z has minimum transverse momentum of 200 GeV. This is then searched for subjets via two methods: a Cambridge/Aachen algorithm and a modified Mass-Drop Tagger with different z-cut values. The sub

Mörk materia upptäcktes redan på 1930-talet av astronomer via sin enorma gravitationella påverkan på galaxer. Trots detta, har alla försök att hitta dess beståndsdelar via experiment misslyckats. Ledande modeller för den mörka materians natur brukar beskriva den som uppbyggd av så kallade ”WIMP:s” (weakly interacting massive particles) som översätts till ungefär: ”svagt interagerande massiva partiRecently, a number of experiments have been proposed with the aim of finding light dark matter. In particular, the proposed LDMX experiment is meant to utilize electron scattering off metal nuclei to excite dark matter emissions. Motivated by this, we construct an event generator for electrons scattering off metal nuclei. The relevant kinematics are presented in detail. The matrix element for the

När en utredare observerar en olycksplats är bevisen de kan hitta viktiga. Bevisen är det som gör att de kan återskapa hur olyckan hände och förstå vad som hände. Men om de inte förstår bevisen, eller använder dom för att återskapa olycksplatsen på fel sätt, kan svaret de får vara fel. Inom partikelfysik kolliderar vi atomkärnor med extrema energier för att se vilka hemligheter universum har. För The purpose of this thesis was to implement an alternative method to calculate the overlap function, which describe to what extent two protons overlap with each other spatially, into PYTHIA8 in order to determine how it affected the average number of multiparton interactions. The new overlap function is based on an explicit impact parameter picture, whereas PYTHIA8s overlap function uses an implic

We describe and compare how methods based on the classicalRice’s formula for the expected number, and higher moments, of level crossingsby a Gaussian process stand up to contemporary numerical methods toaccurately deal with crossing related characteristics of the sample paths.We illustrate the relative merits in accuracy and computing time of the Ricemoment methods and the exact numerical method, We describe and compare how methods based on the classical Rice’s formula for the expected number, and higher moments, of level crossings by a Gaussian process stand up to contemporary numerical methods to accurately deal with crossing related characteristics of the sample paths.We illustrate the relative merits in accuracy and computing time of the Rice moment methods and the exact numerical meth

In response to growing criticism of new public management reforms, the Nordic countries have introduced so-called trust reforms aimed at transforming public sector management and leadership. There is, however, scarce knowledge about the role of organizational concepts in national trust reform and how they are translated, not least in a comparative perspective. This study offers an in-depth analysiIn response to growing criticism of new public management reforms, the Nordic countries have introduced so-called trust reforms aimed at transforming public sector management and leadership. There is, however, scarce knowledge about the role of organizational concepts in national trust reform and how they are translated, not least in a comparative perspective. This study offers an in-depth analysi

I denna uppsats härleds och testas en ny omviktningsalgoritm med vars hjälp det nativa tillståndet av aminosyresekvenser, bestående av 16 aminosyror, kan förutspås. Algoritmen används till att kartlägga de neutrala näten av α-helixes och β-sheets inom ett kontinuerligt proteinmodell. För att undersöka omviktningsalgoritmens potential för att förutsäga den termodynamiska stabiliteten av olika aminIn this thesis, a new reweighting algorithm for predicting the native conformations of amino acid sequences, consisting of 16 residues in a reduced representation continuous protein model, is derived and tested to map neutral nets of α-helices and β-sheets. For examining the potential of the reweighting algorithm for predicting the thermodynamic stability of amino acid sequences, it is applied to

Emulsion formation by homogenization is commonly used in food production and research to increase product stability and to design colloidal structures. High-energy methods such as high-pressure homogenizers and rotor–stator mixers are the two most common techniques. However, to what extent does the research community understand the emulsion formation taking place in these devices? This contributioEmulsion formation by homogenization is commonly used in food production and research to increase product stability and to design colloidal structures. High-energy methods such as high-pressure homogenizers and rotor-stator mixers are the two most common techniques. However, to what extent does the research community understand the emulsion formation taking place in these devices? This contributio

Den mänskliga hjärnan är kanske det mest avancerade och komplexa system som vi känner till. Den är kapabel både till att skapa kreativa tankar och idéer och också till att skapa och minnas erfarenheter och lära sig från dem. Vetenskapen har kommit långt i utforskningen av hjärnans struktur, och idéer om hur vi kan ta till oss och använda den kunskapen är många. I hjärnan finns ett nätverk av nervcThe Maxout network is an alternative to artificial neural networks that use fixed activation functions. By adding extra layers of linear nodes the Maxout network is able to learn both the relationship between the hidden nodes and the activation function that they use. The idea was presented as a natural companion to the dropout technique when training large convolutional networks, showing state-of

This study seeks to examine the nationalist ideological positioning of the Swedish parliament’s only self-proclaimed nationalist party, the Sweden Democrats (SD). The understanding of nationalism differs heavily in the social sciences and a variety of distinctions have been proposed in the study of it. The most common of these distinctions is the one between civic and ethnic nationalism. The metho

This study is about changes of institutional values in the procedur of public procurement. The results show that there is a change of focus from government values to market values in the policies and recommendations from the Swedish Competition Authority. The method of the study is a text analysis of the material presented on the homepage of the Swedish Competion Authority and also covers analysis