6 resultados para Standard Model (SM)

em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland


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The properties and cosmological importance of a class of non-topological solitons, Q-balls, are studied. Aspects of Q-ball solutions and Q-ball cosmology discussed in the literature are reviewed. Q-balls are particularly considered in the Minimal Supersymmetric Standard Model with supersymmetry broken by a hidden sector mechanism mediated by either gravity or gauge interactions. Q-ball profiles, charge-energy relations and evaporation rates for realistic Q-ball profiles are calculated for general polynomial potentials and for the gravity mediated scenario. In all of the cases, the evaporation rates are found to increase with decreasing charge. Q-ball collisions are studied by numerical means in the two supersymmetry breaking scenarios. It is noted that the collision processes can be divided into three types: fusion, charge transfer and elastic scattering. Cross-sections are calculated for the different types of processes in the different scenarios. The formation of Q-balls from the fragmentation of the Aflieck-Dine -condensate is studied by numerical and analytical means. The charge distribution is found to depend strongly on the initial energy-charge ratio of the condensate. The final state is typically noted to consist of Q- and anti-Q-balls in a state of maximum entropy. By studying the relaxation of excited Q-balls the rate at which excess energy can be emitted is calculated in the gravity mediated scenario. The Q-ball is also found to withstand excess energy well without significant charge loss. The possible cosmological consequences of these Q-ball properties are discussed.

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Diplomityössä perehdyttiin toimitusketjun hallinnan ja johtamisen apuvälineenä käytettävään SCOR-malliin (Supply Chain Operations Refence-model). SCOR on standardimalli, josta jokaisen tulee poimia oman toiminnan kehittämisen ja tehostamisen kannalta tärkeät asiat. SCOR on hyvä instrumentti kasvun hallinnassa.Työn teoriaosa käsittelee logistiikkaa, toimitusketjun hallintaa, ostotoimintaa ja SCOR-mallia. Soveltavassa osassa käsitellään SCOR-mallin avulla sisäilma alalla toimivan yrityksen prosesseja. Työssä keskityttiin tarkastelemaan yrityksen ostotoiminta ja valmistusprosesseja SCOR-mallin avulla.SCOR-mallin käyttö oston ja tuotannon analysoinnissa toi esiin useita toiminnan kehitysajatuksia. Näitä olivat uusien menetelmien käyttöönotto varaston ja tuotannon hallittavuuden parantamiseksi, osto-organisaation selkiyttäminen ja toiminnanohjausjärjestelmän kehittäminen.

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Työ lähti liikkeelle Etelä-Karjalan sosiaali- ja terveyspiirin Apuvälinekeskuksen tarpeesta. Eksoten, apuvälinekeskuksen ja Etelä-Karjalan hankintapalveluiden perustaminen sekä muut organisaatiomuutokset muuttivat apuvälineiden hankintaprosessi niin paljon, että sen etenemisestä kaivattiin selventävää kuvausta. Julkisten hankintojen lain mukaan kilpailutettavat hankinnat siirtyivät hankintapalveluiden hoidettavaksi ja niitä varten tarvittiin tarjouspyyntömalli, jonka perusteella tarjouksia voidaan vertailla. Teoriaosuudessa käsitellään hankintaprosessia, julkisten hankintojen erityispiirteitä ja lakia julkisista hankinnoista. Lisäksi käsitellään apuvälinepalveluprosessia ja suosituksia apuvälineiden hankinnasta. Organisaation tutustuttiin henkilökohtaisesti sekä haastattelujen ja sähköpostikyselyiden avulla. Näitä tietoja hyödyntäen luotiin prosessikuvaukset sekä apuvälinepalveluprosessista että apuvälineiden kausisopimustuotteiden hankinnasta. Molempiin kuvauksiin sisältyy selittäviä lisäosia. Tarjouspyyntömallin kehittämisen pohjaksi pyydettiin sähköpostikyselyllä 10 alueellisesta apuvälinekeskuksesta tietoa heidän käyttämistään tarjouspyynnöistä. Vastauksia saatiin 4 kappaletta. Tiedoista tehtiin yhteenveto, joka luovutettiin apuvälinekeskuksen hankintatyöryhmän käyttöön.

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The Standard Model of particle physics is currently the best description of fundamental particles and their interactions. All particles save the Higgs boson have been observed in particle accelerator experiments over the years. Despite the predictive power the Standard Model there are many phenomena that the scenario does not predict or explain. Among the most prominent dilemmas is matter-antimatter asymmetry, and much effort has been made in formulating scenarios that accurately predict the correct amount of matter-antimatter asymmetry in the universe. One of the most appealing explanations is baryogenesis via leptogenesis which not only serves as a mechanism of producing excess matter over antimatter but can also explain why neutrinos have very small non-zero masses. Interesting leptogenesis scenarios arise when other possible candidates of theories beyond the Standard Model are brought into the picture. In this thesis, we have studied leptogenesis in an extra dimensional framework and in a modified version of supersymmetric Standard Model. The first chapters of this thesis introduce the standard cosmological model, observations made on the photon to baryon ratio and necessary preconditions for successful baryogenesis. Baryogenesis via leptogenesis is then introduced and its connection to neutrino physics is illuminated. The final chapters concentrate on extra dimensional theories and supersymmetric models and their ability to accommodate leptogenesis. There, the results of our research are also presented.

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This case study explored value proposition and relationship marketing de-terminants in the HVAC (Heating, Ventilation and Air Conditioning) indus-try. Concretely, the case involved Purmo, a prominent brand and market leader radiator manufacturer, its relationship marketing practices with the retailers of their product (radiator installers) and the value proposition which is being used to reach the end-user. In the field work, five heating experts/entrepreneurs in the installation business were interviewed and asked about their opinion on Purmo and the end-user’s needs. The findings suggest that while installers appreciate Purmo as a supplier and respect it as a company, the loyalty that they have towards it has no repercussions on their product advocacy to ultimate consumers. Installers proved to be attracted to standard model radiators and to be apathetic to the benefits that more advanced models can provide. The reasons for this behavior were found to be their preference for products with better availa-bility and their reluctance to interfere with the customers’ decision making processes.

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Simplifying the Einstein field equation by assuming the cosmological principle yields a set of differential equations which governs the dynamics of the universe as described in the cosmological standard model. The cosmological principle assumes the space appears the same everywhere and in every direction and moreover, the principle has earned its position as a fundamental assumption in cosmology by being compatible with the observations of the 20th century. It was not until the current century when observations in cosmological scales showed significant deviation from isotropy and homogeneity implying the violation of the principle. Among these observations are the inconsistency between local and non-local Hubble parameter evaluations, baryon acoustic features of the Lyman-α forest and the anomalies of the cosmic microwave background radiation. As a consequence, cosmological models beyond the cosmological principle have been studied vastly; after all, the principle is a hypothesis and as such should frequently be tested as any other assumption in physics. In this thesis, the effects of inhomogeneity and anisotropy, arising as a consequence of discarding the cosmological principle, is investigated. The geometry and matter content of the universe becomes more cumbersome and the resulting effects on the Einstein field equation is introduced. The cosmological standard model and its issues, both fundamental and observational are presented. Particular interest is given to the local Hubble parameter, supernova explosion, baryon acoustic oscillation, and cosmic microwave background observations and the cosmological constant problems. Explored and proposed resolutions emerging by violating the cosmological principle are reviewed. This thesis is concluded by a summary and outlook of the included research papers.