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Denna uppsats undersöker den kvantitativa och den kvalitativa forskningsmetoden ur ett kunskapsteoretiskt och ett vetenskapsteoretiskt perspektiv. I fråga om kvalitativ forskning har metoderna hermeneutik och fenomenologi studerats särskilt grundligt. Uppsatsen argumenterar för att kunskapsteoretiska och vetenskapsteoretiska antaganden måste vara gemensamma för de båda typerna av metod, om man anser att båda typerna ska betraktas som vetenskapliga. Vidare hävdas att de kvalitativa metoderna är sammankopplade med en rad problem beträffande objektivitet, generaliserbarhet, rättfärdigande av kunskap och teoriers empiriska stöd. I många fall utger sig dessa metoder för att leva upp till de krav man ställer på vetenskaplig forskning i dessa avseenden i lika hög grad som kvantitativ metod, men en av uppsatsens teser är att de misslyckas med detta. I uppsatsen hävdas att vetenskapens mål är att generera generaliserbar kunskap. På grund av de kunskapsteoretiska problem kvalitativ forskning stöter på, kan sådan forskning inte ensam nå detta mål och således inte ha någon självständig plats i vetenskapen, utan kan endast tjäna ett förvetenskapligt syfte, genom att, i vissa fall, formulera frågor och hypoteser som sedan besvaras respektive testas av kvantitativ forskning. / This paper examines the quantitative and the qualitative research methods with respect to both epistemology and the philosophy of science. With regards to qualitative research, the paper takes a closer look at the hermeneutic and the phenomenological methods in particular. The paper argues that the different types of method must have the same epistemological assumptions, if it is held that both types ought to be considered scientific. It is further claimed that the qualitative methods are connected to several problems concerning objectivity, generalizability, the justification of knowledge and the empirical support of theories. In many cases, these methods purport to live up to the requirements that are made on scientific research in these respects to the same degree as the quantitative method, but one of the theses of this paper is that they fail to do this. In the paper, it is maintained that the goal of science is to generate generalizable knowledge. Due to the epistemological problems qualitative research are faced with, such research cannot reach that goal alone and thus cannot hold an independent position in science, but can only serve a prescientific purpose, by, in some cases, drawing up questions and hypotheses which are then answered and tested respectively, by quantitative research.

Syftet med studien är att undersöka hur ett globalt management konsultföretag arbetar internt med kunskapsöverföring över landsgränser av den svåruttryckliga erfarenhetsbaserade kunskapen som en konsult innehar. Den kvalitativa data som används i empirin samlades in genom intervjuer med anställda på fallföretaget Accenture. Resultatet av undersökningen visade att praktisk kunskap överförs genom formella sammankomster samt en ”learning by doing” modell där konsulter av olika nationaliteter och grad av erfarenhet arbetar tillsammans på olika projekt. Erfarenheter från projekt samlas, lagras och överförs till databasen Knowledge Exchange, i en process där den praktiska kunskapen transformeras till teoretisk kunskap och görs tillgänglig för hela företaget. Studien visar att Accenture har rutiner som gör att dem överkommer de flesta hinder som presenteras i den befintliga teorin. Det hinder som Accenture belyste som ett problem var informationsöverflödet som fanns inom företaget. / The purpose of the study is to study how a global management consulting firm works internally with knowledge transfer across national borders of the hard to express, experience-based knowledge of a consultant. The qualitative data which is presented in the empirical part of the paper was collected through interviews with employees at the case firm Accenture. The result of the study showed that practical knowledge is transferred through formal meetings, and a “learning by doing” process, where consultants of different nationalities and degrees of experience work together on projects. Experiences from projects are collected, stored, and transferred to the Knowledge Exchange database, in a process where the practical knowledge is transformed into theoretical knowledge and made available to the entire company. The study shows that Accenture has routines that help them overcome most of the impediments presented in the existing theory. The impediment that Accenture expressed to be a problem within their organization was information overflow.

The overall aim of this thesis is to compare different methods for calculation of Core-Level shifts in metallic alloys. The methods compared are the Initial State model, the Complete screening and the Transition state model. Core-level shifts can give information of chemical bonding and about the electronic structure in solids. The basic theory used is the so-called Density-Functional-Theory, in conjunction with the Local-Density Approximation and the Coherent-Potential- Approximation. The metallic alloys used are Silver-Palladium, Copper-Palladium, Copper-Gold and Copper-Platinum, all inface-centered-cubic configuration. The complete screening- and the transition-state model are found to be in better agreement with experimental results than those calculated with the initial state model. This is mainly due to the fact that the two former models includes final-state effects, whereas the last one do not. The screening parameters within the Coherent-Potential approximation are also investigated. It is found that the Screened-Impurity Model can extend the validity of the Coherent-Potential-Approximation and increase it's accuracy.

The topic of this study is to what extent standards of rational inquiry can be rationally criticized and revised. It is argued that it is rational to treat all such standards as open to criticism and revision. Arguments to the effect that we are fallible with regard to all standards of rational inquiry are presented. Standards cannot be ultimately justified and with certainty established either as adequate or as inescapable presuppositions. Apel's attempt to give ultimate justifications of certain moral and logical rules is examined and criticized. Special attention is given to our fallibility with regard to logical inference rules. The idea that certain logical rules cannot be put into question because any critical argument presupposes them is criticized. It has been claimed that there must be some basic standards which are such that they cannot be rationally evaluated and hence are rationally unrevisable. This is called "the unrevisability thesis". Related to this thesis is the normative policy according to which rationality requires that some standards be treated as unrevisable, the unrevisability policy. Two arguments that have been used to defend the unrevisability thesis and policy are examined and criticized. The conclusion is that we are not forced to accept either the thesis or the policy. The negation of the unrevisability policy is the revisability policy, according to which it is rational to treat all standards as open to rational criticism and revision. Objections that have been directed against the revisability policy are discussed and criticized. According to the objections, the revisability policy leads to rationality relativism. These objections are refuted, and it is argued that it is, on the contrary, rational to adopt the revisability policy and treat all standards of rational inquiry as criticizable and revisable. It is proposed that the rational change of standards should be viewed as a bootstrap process. General features of a bootstrap view of rational change of standards are presented, and it is argued that it is impossible to formulate a real theory of bootstrapping. Two models of standard change are presented and discussed: Laudan's reticulated model of scientific rationality and Briskman's bootstrap theory. It is claimed that in spite of defects and limitations, these models contribute to a richer understanding of bootstrapping. The fallibility and revisability of standards of rational inquiry have consequences for how the normativity of rationality should be understood. The book ends with an account of how the rationality of cognitive actions is related to the idea of the adequacy of standards. A distinction between absolute and standard-relative rationality is made, and it is argued that what an inquiring agent rationally ought to do coincides with what it is standard-relatively rational for him to do. It is shown that this view of rationality of inquiry is nevertheless inconsistent with rationality relativism, and that it is compatible with an objectivistic view of rationality. / digitalisering@umu

Knowledge about the insertion and stabilization of membrane proteins is a key step towards understanding their function and enabling membrane protein design. Transmembrane helices are normally quite hydrophobic to insert efficiently, but there are many exceptions with unfavorable polar or titratable residues. Since evolutionary conserved these amino acids are likely of paramount functional importance, e.g. the four arginines in the S4 voltage sensor helix of voltage-gated ion channels. This has lead to vivid discussion about their conformation, protonation state and cost of insertion. To address such questions, the main focus of this thesis has been membrane protein solvation in lipid bilayers, evaluated using molecular dynamics simulations methods. A main result is that polar and charged amino acids tend to deform the bilayer by pulling water/head-groups into the hydrophobic core to keep their hydrogen bonds paired, thus demonstrating the adaptiveness of the membrane to allow specific and quite complex solvation. In addition, this retained hydration suggests that the solvation cost is mainly due to entropy, not enthalpy loss. To further quantify solvation properties, free energy profiles were calculated for all amino acids in pure bilayers, with shapes correlating well with experimental in vivo values but with higher magnitudes. Additional profiles were calculated for different protonation states of the titratable amino acids, varying lipid composition and with transmembrane helices present in the bilayer. While the two first both influence solvation properties, the latter seems to be a critical aspect. When the protein fraction in the models resemble biological membranes, the solvation cost drops significantly - even to values compatible with experiment. In conclusion, by using simulation based methods I have been able to provide atomic scale explanations to experimental results, and in particular present a hypothesis for how the solvation of charged groups occurs.

This thesis describes some aspects of noncommutative geometry and conformal field theory. The motivation for the investigations made comes to a large extent from string theory. This theory is today considered to be the most promising way to find a solution to the problem of unifying the four fundamental interactions in one single theory. The thesis gives a short background presentation of string theory and points out how noncommutative geometry and conformal field theory are of relevance within the string theoretical framework. There is also given some further information on noncommutative geometry and conformal field theory. The results from the three papers on which the thesis is based are presented in the text. It is shown in Paper 1 that, for a gauge theory in a flat noncommutative background only the gauge groups U(N) can be used in a straightforward way. These theories can arise as low energy limits of string theory. Paper 2 concerns boundary conformal field theory, which can be used to describe open strings in various backgrounds. Here different orbifold theories which are described using simple currents of the chiral algebra are investigated. The formalism is applied to ``branes´´ in Z2 orbifolds of the SU(2) WZW-model and to the D-series of unitary minimal models. In Paper 3 two different descriptions of an invariant star-product on S² are compared and the characteristic class that classifies the star-product is calculated. The Fedosov-Nest-Tsygan index theorem is used to compute the characteristic class.

Björn Alm Specialundervisning som hjälp för att uppnå målen Remedial teaching as a help reaching the goals Abstract Syftet med undersökningen var att beskriva några elevers upplevelser och syn på specialundervisning och den hjälp de får för att uppnå kunskapsmål och värdegrundsmål; dels att sätta elevernas upplevelser i förhållande till ett par specialpedagogers erfarenhet/syn på undervisning i mindre grupp. Andra intressanta aspekter var att ha styrdokumenten/genus/etnicitet i åtanke som eventuella påverkande-faktorer. Vilken klassifikation och inramning har osynlig/synlig pedagogik och kan man se en förhållningssätt i förhållande till vetenskapsteoretiska utgångspunkter. Förhållningssätten har ju betydelse för vilken genomslagskraft specialundervisning har som problemlösare i dagens skola. Elevernas socialisationsprocesser och pedagogiska möten kan leda till olika beroendeförhållanden i skolan som nätverk men även då det gäller deras övriga existensbetingelser. Ett urval av observationer,elevintervjuer och lärarintervjuer har gjorts. Informationsmängden och dess kvalitet är viktig, för att eventuella lösningar till problemet ska uppdagas. En annan viktig faktor är tillvägagångssättet för att uppnå en hög validiteten/kvaliteten av undersökningen. Bourdieus begrepp innebär att inte se eleverna som enkla bärare av sociala klasstrukturer (reproduktion) utan istället se till totalbilden och summan av elevens alla egenskaper, erfarenheter och förutsättningar. Studien avslutas med en diskussion av resultaten och varför det ser ut som det gör. Vad kan orsakerna vara och varför är två viktiga aspekter. Objektiv och subjektiv bedömning av reproduktionsfaktorer och handlingsstrategier som har inflytande på resultatet tydliggörs.

<p>This thesis is part of an effort to enable large-scale Hartree-Fock/Kohn-Sham (HF/KS) calculations. The objective is to model molecules and materials containing thousands of atoms at the quantum mechanical level. HF/KS calculations are usually performed with the Self-Consistent Field (SCF) method. This method involves two computationally intensive steps. These steps are the construction of the Fock/Kohn-Sham potential matrix from a given electron density and the subsequent update of the electron density usually represented by the so-called density matrix. In this thesis the focus lies on the representation of potentials and electron density and on the density matrix construction step in the SCF method. Traditionally a diagonalization has been used for the construction of the density matrix. This diagonalization method is, however, not appropriate for large systems since the time complexity for this operation is σ(n³). Three types of alternative methods are described in this thesis; energy minimization, Chebyshev expansion, and density matrix purification. The efficiency of these methods relies on fast matrix-matrix multiplication. Since the occurring matrices become sparse when the separation between atoms exceeds some value, the matrix-matrix multiplication can be performed with complexity σ(n).</p><p>A hierarchic sparse matrix data structure is proposed for the storage and manipulation of matrices. This data structure allows for easy development and implementation of algebraic matrix operations, particularly needed for the density matrix construction, but also for other parts of the SCF calculation. The thesis addresses also truncation of small elements to enforce sparsity, permutation and blocking of matrices, and furthermore calculation of the HOMO-LUMO gap and a few surrounding eigenpairs when density matrix purification is used instead of the traditional diagonalization method.</p>

<p>In this thesis I have theoretically studied electron recombination processes with small molecular ions.</p><p>In these kind of processes resonant states are involved. To calculate the potential energy for these states as a function of internuclear distance, structure calculations and scattering calculations have to be performed.</p><p>So far I have been studying the ion-pair formation with in electron recombination with H₃⁺. The cross section for this process has been calculated using different kind of models, both a time dependent quantum mechanical and a semiclassical.</p><p>I have also studied the direct process of dissociative recombination of HF⁺. To calculate the total cross section for this process, we have performed wave packet propagation on thirty resonant states and summed up the individual cross sections for these states.</p><p>The cross sections for both these processes have a similar appearance to those measured experimentally in the ion storage ring CRYRING in Stockholm.</p>