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In a world with unlimited travel options, railways play a key role in transportation. In order to serve the demand at a satisfactory level, it is important that the infrastructure quality remains high and safe. Maintenance is then the most important aspect of railway infrastructure.  This project’s aim is to develop a tool that would evaluate the cost differences and maintenance needs during the life cycle of turnouts, bent with different radii to straight, as a crucial part of the infrastructure, not only technically but also financially. When the cost over a life cycle is provided then design decisions can get more efficient.  Maintenance history of seven years of preventive and corrective maintenance data from databases Bessy and 0felia for single turnouts across the Swedish rail network were studied, analysed and evaluated.  Along with information from interviews with key informants the cost driving parameters were specified. The calculator was developed in Microsoft Excel, giving results for bent turnouts in 4 different radii categories and the respective straight turnouts. An EV-UIC60-760-1:14 turnout was used as a case study for different radii categories and 3 different scenarios were run in order to test the robustness of the tool.  The results showed that bent turnouts have a higher life cycle cost than straight in the order of 1 to 3 mkr depending on the radius, the bigger share of which is usually the preventive maintenance cost, with the specifics to vary between the categories and different scenarios tested. The way maintenance data are registered and classified plays an important role in the analysis.

To ensure an educational opportunity for every child that passes through America's schoolhouse doors, it is imperative that non-heterosexual students' educational needs are not ignored in the educational milieu (Zirkel, 2006). In the last decade or so, the desire of non-heterosexual students to organize Gay-Straight Alliance (GSA) clubs on high school campuses have been met with angst by school leaders (Duncan & Rogers, 2008). Despite the passage of the Equal Access Act (EAA) in 1984, school leaders have often denied non-heterosexual students the right to establish GSA clubs on campus, consequently resulting in these students utilizing the judicial system as the venue to assert their rights under the law (Essex, 2005). As it is imperative that educational leaders understand the legal rights of all students under their care, and make informed decisions in order to avoid costly litigation, this research focused on analyzing the Equal Access Act of 1984, federal case law, legal commentary, and historical documents, in order to track the developments of non-heterosexual students' ability to utilize the EAA to establish GSA clubs in the public schools in the United States. The study employed a traditional legal research methodology as described by Alder (1993) and Russo (1993), relying on electronic data bases and traditional legal finding tools to carry out the research. From the resulting legislation, case law, scholarly commentary, and other relevant documents reviewed and analyzed, an accurate historical perspective on the EAA as it relates to the formation of GSA clubs was constructed. In addition, the significant themes that arose from the findings were synthesized in order to offer guidance to educational leaders and policymakers when facing requests from students to establish GSA clubs on school property. Recommendations for school leaders when considering such requests from students to form GSA clubs under the EAA are provided. / Ed. D.

In designing devices to produce straight-line motion, the designer has a fundamental choice between selecting sliding devices or selecting pinned linkages. Although they are more complex to design and implement, linkages will often prove a less expensive, more efficient, and generally more satisfactory option than simple sliders. The objective of this thesis is to provide a tool to the designer that serves as an aid in making intelligent decisions in the selection of four-bar linkage type straight-line-mechanisms. This thesis provides research into the selection, evaluation, and implementation of existing straight-line mechanism designs. Twenty-two straight-line mechanisms are compared for both compactness and fidelity of the straight-line path. Also, figures showing position, velocity, and acceleration of each a included. The functional product of to this work is a software program called Straight-line. Straight-line gives the designer a graphical environment from which a wide variety of straight-line mechanisms can be quickly analyzed and evaluated. The software also provides a new type-synthesis technique that allows the designer to generate a straight-line-mechanism by graphically inputting a desired path. / Master of Science

Advances in structural systems that resist extreme loading such as earthquake forces are important in their ability to reduce damages, improve performance, increase resilience, and improve the reliability of structures. Buckling resistant shear panels can be used to form new structural systems, which have been shown in preliminary analysis to have improved hysteretic behavior including increased stiffness and energy dissipating ability. Both of these characteristics lead to reduced drifts during earthquakes, which in turn leads to a reduction of drift related structural and nonstructural damage. Shear links are being used for seismic energy dissipation in some structures. A promising type of fuse implemented in structures for seismic energy dissipation, and seismic load resistance consists of a steel plate with cutouts leaving various shaped shear links. During a severe earthquake, inelastic deformation and damage would be concentrated in the shear links that are part of replaceable structural fuses, while the other elements of the building remain in the elastic state. In this study, by identifying the issues associated with general fuses previously used in structures, the behavior of the links is investigated and procedures to improve the behavior of the links are explained. In this study, a promising type of hysteretic damper used for seismic energy dissipation of a steel plate with cutouts leaving butterfly-shaped links subjected to shear deformations. These links have been proposed more recently to better align bending capacity with the shape of the moment diagram by using a linearly varying width between larger ends and a smaller middle section. Butterfly-shaped links have been shown in previous tests to be capable of substantial ductility and energy dissipation, but can also be prone to lateral torsional buckling. The mathematical investigations are conducted to predict, explain and analyze the butterfly-shaped shear links behavior for use in seismic structural fuses. The ductile and brittle limit states identified based on the previous studies, are mathematically explained and prediction equations are proposed accordingly. Design methodologies are subsequently conceptualized for structural shear links to address shear yielding, flexural yielding and buckling limit states for a typical link subjected to shear loading to promote ductile deformation modes. The buckling resistant design of the links is described with the aid of differential equations governing the links' buckling behavior. The differential equations solution procedures are developed for a useful range of link geometries and the statistical analysis is conducted to propose an equation for critical buckling moment. Computational studies on the fuses are conducted with finite element analysis software. The computational modeling methodology is initially verified with laboratory tests. Two parametric computational studies were completed on butterfly-shaped links to study the effect of varying geometries on the shear yielding and flexural yielding limit states as well as the buckling behavior of the different butterfly-shaped link geometries. It is shown that the proposed critical moment for brittle limit state has 98% accuracy, while the prediction equations for ductile limit states have more than 97% accuracy as well. Strategies for controlling lateral torsional buckling in butterfly links are recommended and are validated through comparison with finite element models. The backbone behavior of the seismic butterfly-shaped link is formulized and compared with computational models. In the second parametric study, the geometrical properties effects on a set of output parameters are investigated for a 112 computational models considering initial imperfection, and it is indicated that the narrower mid-width would reach to their limit states in lower displacement as compared to wider mid-width ones. The work culminates in a system-level validation of the proposed structural fuses with the design and analysis of shear link structural fuses for application in three buildings with different seismic force resisting systems. Six options for shear link geometry are designed for each building application using the design methodologies and predictive equations developed in this work and as guided by the results of the parametric studies. Subsequently, the results obtained for each group is compared to the conventional systems. The effect of implementation of the seismic links in multi-story structures is investigated by analyzing two prototype structures, with butterfly-shaped links and simple conventional beam. The results of the nonlinear response history analysis are summarized for 44 ground motions under Maximum Considered Event (MCE) and Design Basic Earthquake (DBE) ground motion hazard levels. It is shown that implementation of the butterfly-shaped links will lead to higher dissipated energy compared to conventional Eccentrically Braced Frame (EBF) systems. It is concluded that implementation of the seismic shear links significantly improves the energy dissipation capability of the systems compared to conventional systems, while the stiffness and strength are close in these two systems. / Ph. D. / Structural fuses are replaceable elements of a structure that are designed to yield and protect the surrounding members from damages, and then be accessible and replaceable after a major event. Several studies have indicated that steel plates with cutouts would have advantages for use in structural fuses. Having cutouts in a steel plate would make different shapes inside of the plate, which are called structural links. To have the same yielding condition all over the links, it is tried to better align the capacity of the links with the shape of the demand diagram caused by loading, which would be leading to the efficient implementation of the steel. In general, links are implemented to substantially increase the energy dissipation capacity of a structure and significantly reduce the energy dissipation demand on the framing members of a structure. For these purposes, various shapes have been proposed in this research study. The main feature of a replaceable link system is that the inelasticity is concentrated at the steel link while the beams and columns remain almost elastic. This study investigated the general behavior of the fuses, the applicability of them for space-constrained applications, the flexure, shear and buckling limit states affecting the behavior of the links. The computational analysis methodologies to model the links are explained and confirmed with the behavior of the different experiment tests as well as the proposed brittle limit state prediction equations. Subsequently, the two parametric studies are done to investigate the effect of geometrical properties on the links output results and establish prediction equations. The results from the analytical and computational studies for the seismic links are incorporated for seismic investigation of multi-story buildings. The results of seismic analysis of the two buildings are summarized for 44 ground motions.

This master’s thesis investigates normative lifelines, time and space in relation to a nonbinary gender identity. My research questions focused on nonbinary aging, orientation in regards to identity and spaces, and views on maturity. I wanted to know how temporality and spatiality can be used as a theoretic framework to better understand nonbinary people’s experiences. This was achieved by interviewing seven Swedish nonbinary subjects aged 30-41 about norms regarding time and place. The results show that the nonbinary informants use gender norms to orient themselves in relation to gender identity. Aging is shown to be a gendered practice and therefore nonbinary aging and what the future will hold is made unclear for the participants. Nonbinary people seek not to be a hindrance or annoyance to the outside world and are aware that their identity often is viewed as childish, made up and illegitimate. Despite fears that they take up too much space I have shown that there is not enough space for nonbinary subjects to comfortably find a place in most rooms.

With this essay, I’m reviewing with a narrative analysis, describing in what way the standards of feminism, bisexuality and non-monogomy is being represented in the movie Puccini for beginners. I’m reviewing this in support of a queer and straight time. As a complement for queer and straight time, I’m presenting different theoretical concepts, which are useful for the analyze of feminism, bisexuality and non-monogamy. The analyze is based on the categories of Labov. In which way the narritve is constructed, as well as in what way feminism, bisexuality and non-monogamy are being represented. Finally I’m summing-up how I answered my questions regarding straight and queer time in perspective of feminism, bisexuality and non-monogamy.

Diese Arbeit beinhaltet {\it geometrische Algorithmen} zur L\"osung reeller polynomialer Gleichungssysteme mit rationalen Koeffizienten, wobei die Polynome eine reduzierte regul\"are Folge bilden (vgl. Abschnitt \ref{abschgeo}). Unter reellem L\"osen verstehen wir hier die Bestimmung eines Punktes in jeder Zusammenhangskomponente einer kompakten glatten reellen Variet\"at $V:=W \cap \R^n$.\\ Im Mittelpunkt steht die Anwendung des f\"ur den algebraisch abgeschlossenen Fall ver\"offentlichten symbolischen geometrischen Algorithmus nach \cite{gh2} und \cite{gh3}. Die Berechenungsmodelle sind {\em Straight--Line Programme} und {arithmetische Netzwerke} mit Parametern in $\; \Q$. Die Input--Polynome sind durch ein Straight--Line Programm der Gr\"o{\ss}e $L$ gegeben. Eine geometrische L\"osung des Input--Glei\-chungs\-sys\-tems besteht aus einem primitiven Element der Ringerweiterung, welche durch die Nullstellen des Systems beschrieben ist, aus einem mininalen Polynom dieses primitiven Elements, und aus den Parametrisierungen der Koordinaten. Diese Darstellung der L\"osung hat eine lange Geschichte und geht mindestens auf Leopold Kronecker \cite{kron} zur\"uck. Die Komplexit\"at des in dieser Arbeit begr\"undeten Algorithmus erweist sich als linear in $L$ und polynomial bez\"uglich $n, d, \delta$ bzw. $\delta \;'$, wobei $n$ die Anzahl der Variablen und $d$ eine Gradschranke der Polynome im System ist. Die Gr\"o{\ss}en $\delta$ und $\delta \; '$ sind geometrische Invarianten, die das Maximum der {\em Grade des Inputsystems} und geeigneter {\em polarer Variet\"aten} repr\"asentieren (bzgl. des ({\em geometrischen}) Grades vgl. \cite{he}). Die Anwendung eines Algorithmus \"uber den komplexen Zahlen auf das L\"osen von polynomialen Gleichungen im Reellen wird durch die Einf\"urung polarer Variet\"aten m\"oglich (vgl. \cite{bank}). Die polaren Variet\"aten sind das Kernst\"uck und das vorbereitende Werzeug zur effizienten Nutzung des oben erw\"ahnten geometrischen Algorithmus. Es wird ein inkrementelles Verfahren zur Auffindung reeller Punkte in jeder Zusammenhangskomponente der Nullstellenmenge des Inputsystems abgeleitet, welches einen beschr\"ankten glatten (lokalen) vollst\"andigen Durchschnitt in $\R^n$ beschreibt. Das Inkrement des Algorithmus ist die Kodimension der polaren Variet\"aten. Die Haupts\"atze sind Satz $\ref{theorem12}$ auf Seite $\pageref{theorem12}$ f\"ur den Hyperfl\"achenfall, und Satz $\ref{theoresult}$ auf Seite $\pageref{theoresult}$, sowie die Aussage in der Einf\"uhrung dieser Arbeit, Seite $\pageref{vollres}$ f\"ur den vollst\"andigen Durchschnitt. / This dissertation deals with {\em geometric algorithms} for solving real multivariate polynomial equation systems, that define a reduced regular sequence (cf. subsection $\ref{abschgeo}$). Real solving means that one has to find at least one real point in each connected component of a real compact and smooth variety $V := W \cap \R^n$. \\ The main point of this thesis is the use of a complex symbolic geometric algorithm, which is designed for an algebraically closed field and was published in the papers \cite{gh2} and \cite{gh3}. The models of computation are {\em straight--line programms} and {\em arithmetic Networks} with parameters in $\; \Q$. Let the polynomials be given by a division--free straight--line programm of size $L$. A geometric solution for the system of equations given by the regular sequence consists in a {\em primitiv element} of the ring extension associated with the system, a minimal polynomial of this primitive element and a parametrization of the coordinates. This representation has a long history going back to {\em Leopold Kronecker} \cite{kron}. The time--complexity of our algorithms turns out to be linear in $L$ and polynomial with respect to $n, d, \delta$ or $\delta '$, respectively. Here $n$ denotes the number of variables, $d$ is an upper bound of the degrees of the polynomials involved in the system, $\delta$ and $\delta '$ are geometric invariants representing the maximum of the {\em affine (geometric) degree} of the system under consideration and the affine (geometric) degree of suitable {\em polar varieties} (cf. \cite{he} for the ({\em geometric}) degree). The application of an algorithm running in the complex numbers to solve polynomial equations in the real case becomes possible by the introduction of polar varieties (cf. \cite{bank}). The polar varieties introduced for this purpose prove to be the corner--stone and the preliminary tool for the efficient use of the geometric algorithm mentioned above. An incremental algorithm is designed to find at least one real point on each connected component of the zero set defined by the input under the assumption that the given semialgebraic set $V = W \cap \R^n$ is a bounded, smooth (local) complete intersection manifold in $\R^n$. The increment of the new algorithm is the codimension of the polar varieties under consideration. The main theorems are Theorem $\ref{theorem12}$ on page $\pageref{theorem12}$ for the hypersurface case, and Theorem $\ref{theoresult}$ on page $\pageref{theoresult}$ for the complete intersection as well as the statement in the introduction of this thesis on page $\pageref{vollres}$.