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Since the discovery of superconductivity, its fantastic properties have fascinated the scientific community. The discovery of high critical temperature (Tc) superconducting compositions further inspires the wide applications of superconductors with relatively inexpensive liquid nitrogen cooling. Recently, the integration of superconductivity and optical waveguides has put forward the potential for ultrasensitive, ultra-fast and ultralow noise light detectors. However, simple and cost effective superconductor designs and fabrication processes are still required to enable wide implementation. The objective of this research was to study the fabrication of the superconductor core fibers with a fused silica cladding via the melt-draw approach, as well as develop appropriate characterization techniques to describe the fibers produced. In addition, a further objective was to determine the cooling efficiency of ordered holes around a superconductor core and construction of a one dimensional (1-D) single-phase steady state model to predict the heat transfer during cryogenic liquid transfer inside glass tube. In this thesis, both Pb and YBCO superconductor core fibers with fused silica cladding have been demonstrated. The fibers were fabricated via the melt-draw technique and maintained overall diameters ranging from 200-900 μm and core diameters of 100-800 μm. Surface morphology, chemical composition, interface effect, and superconductivity were further investigated. Surface morphology analysis confirmed that the Pb and YBCO core fibers possessed good circularity and clean interfaces between the core and cladding. Both the Pb and YBCO cores were relatively dense after the melt-draw process. The melt-draw process avoided contamination during fabrication as indicated by the composition analysis. Limited PbO was examined on the Pb core surface but further action will be required to detect the source of oxygen. The YBCO core maintained a stoichiometric ratio comparable to the superconducting phase even after the melt forming process. The elemental mapping showed that limited cross-diffusion occurred between the Pb core and fused silica cladding. Conversely significantly more elemental cross interaction between the core and cladding was noted for the YBCO core fiber. Superconductivity of the Pb core was verified by a custom designed four-probe technique in liquid helium. The YBCO core was also confirmed to be superconductive after heat treatment with O₂ present. The feasibility of efficient cooling by the holey glass tubes was confirmed. A 1-D single-phase steady state model was constructed to evaluate the heat transfer mechanism. The experimental results are in reasonable agreement to the theoretical calculation. / Master of Science

The book is a series of plates, pictures and writings which are the results of an architectural thesis exploring, line, contour and layers. The plates are scans of original work by the author, made in a combination of media including: pencil, pastel, watercolor, photograph, study models, hand-drafted drawings, and computer aided drawings. A transcript of the presentation of the work at the thesis defense is included. The simple idea is the impression of contour by the expression of layers. The contour is a line tracing the motion and movement of architecture. Resulting from practice in drawing using pastels, pencil and paper the line, through continuity, can twist, pass over, go under and around- joining parts into an organized whole. Following a program of a modern bath, an architectural space is made, built by layers. The thesis is an architectural exploration of layers and the resultant contours. The best representation of this work is available in printed form at the Art and Architecture Library on the Virginia Tech campus in Blacksburg, Virginia. / Master of Architecture

During her theoretical training as an educational psychologist, the researcher was intrigued and fascinated by the expositions on the functioning of the self. With this study she pursued her goal to gain a clearer understanding of the formation and development of the self in a child, with the focus on the child in middle childhood (6 -12 years). In this study, she mainly focused on understanding the connection between the three crucial components of the self, self-concept and self-esteem. Her passion for art inspired her to be inventive and apply artistic creative methods of drawing, painting and clay human modelling as projective means to access the child’s unconscious mind, revealing pivotal experiences and emotions, revealing how the child relates to his or her self. According to this qualitative arts-based research study, the DAP (Draw a Person) and variations of PAP (Paint a Person) and CAP (Create a Person) with the use of appropriate DAP, PAP and CAP questionnaires, seem relevant therapeutic projective measures to assist in educational psychology in exploring the child’s self. / Further Teacher Education / M. Ed. (Guidance and Counselling)

During her theoretical training as an educational psychologist, the researcher was intrigued and fascinated by the expositions on the functioning of the self. With this study she pursued her goal to gain a clearer understanding of the formation and development of the self in a child, with the focus on the child in middle childhood (6 -12 years). In this study, she mainly focused on understanding the connection between the three crucial components of the self, self-concept and self-esteem. Her passion for art inspired her to be inventive and apply artistic creative methods of drawing, painting and clay human modelling as projective means to access the child’s unconscious mind, revealing pivotal experiences and emotions, revealing how the child relates to his or her self. According to this qualitative arts-based research study, the DAP (Draw a Person) and variations of PAP (Paint a Person) and CAP (Create a Person) with the use of appropriate DAP, PAP and CAP questionnaires, seem relevant therapeutic projective measures to assist in educational psychology in exploring the child’s self. / Further Teacher Education / M. Ed. (Guidance and Counselling)

One interesting approach is the development of conductive polymer composite fibers for innovative textile applications such as in sensors, actuators and electrostatic discharge. In this study, conductive polymer composite fibers were prepared using several different blends containing conductive components: a conjugated polymer (polyaniline-complex) and/or carbon nanotubes. Different factors such as processing parameters, the morphology of the initial blends and the final fibers, fiber draw ratio and material selection were studied separately to characterize their effects on the fiber properties. In binary blends of PP/polyaniline-complex, the processing conditions, the matrix viscosity and the fiber draw ratio had substantial effects on the electrical conductivity of the fibers and linearity of resistance-voltage dependence. These factors were associated with each other to create conductive pathways through maintaining an appropriate balance of fibril formation and breakage along the fiber. The blend morphology was defined as the initial size of the dispersed conductive phase (polyaniline-phase), which depended on the melt blending conditions as well as the PP matrix viscosity. Depending on the initial droplet phase size, an optimum draw ratio was necessary to obtain maximum conductivity by promoting fibril formation (sufficient stress) and preventing fibril breakage (no excess stress) to create continuous pathways of conductive phase. Ternary blend fibers of PP/PA6/polyaniline-complex illustrated at least three-phase morphology with matrix/core-shell dispersed phase style. When ternary fibers were compared to binary fibers, the former could combine better mechanical and electrical properties only at a specific draw ratio; this showed that draw ratio was a more determinant factor for the ternary fibers, as both conductivity and tensile strength depended on the formation of fibrils from the core-shell droplets of the PA6/polyaniline-complex through the polypropylene matrix. The achieved maximum conductivity so far was in the range of 10 S/cm to 10 S/cm, which for different samples were observed at different fiber draw ratios depending on the mixing conditions, the matrix viscosity or whether the fiber was a binary or ternary blend. To improve the properties, PP/polyaniline-complex blends were filled with CNTs. The CNTs and the polyaniline-complex both had an increasing effect on the crystallization temperature and the thermal stability of PP. Furthermore, the maximum conductivity was observed in samples containing both CNTs and polyaniline-complex rather than the PP with either one of the fillers. Although increasing the content of CNTs improved the conductivity in PP/CNT fibers, the ease of melt spinning, diameter uniformity and mechanical properties of fibers were adversely affected. Diameter variation of PP/CNT as-spun fibers was shown to be an indication of hidden melt-drawings that had occurred during the fiber extrusion; this could lead to variations in morphology such as increases in the insulating microcracks and the distance between the conductive agglomerates in the drawn parts of the fiber. Variations in morphology result in variations in the electrical conductivity; consequently, the conductivity of such inhomogeneous fiber is no longer its physical property, as this varies with varying size. / Thesis to be defended in public on Friday, May 20, 2011 at 10.00 at KC-salen, Kemigården 4, Göteborg, for the degree of Doctor of Philosophy.

Intensive competition on the global market puts great pressure on manufacturing companies to develop and produce products that meet requirements from customers and investors. One key factor in meeting these requirements is the efficiency of the product development and the production preparation process. Design automation is a powerful tool to increase efficiency in these two processes. The benefits of automating the production preparation process are shortened led-time, improved product performance, and ultimately decreased cost. Further, automation is beneficial as it increases the ability to adapt products to new product specifications with production preparations done in few or in a single step. During the automation process, knowledge about the production preparation process is collected and stored in central systems, thus allowing full control over the design of production equipments. Three main topics are addressed in this thesis: the flexibility of design automation systems, knowledge bases containing conflicting rules, and the automation of the finite element analysis process. These three topics are discussed in connection with the production preparation process of rotary draw bending. One conclusion drawn from the research is that it is possible to apply the concept of design automation to the production preparation process at different levels of automation depending on characteristics of the implemented knowledge. In order to make design automation systems as flexible as possible, the concept of object orientation should be adapted when building the knowledge base and when building the products geometrical representations. It is possible to automate the process of setting up, running, and interpreting finite element analyses to a great extent and making the automated finite element analysis process a part of the global design automation system.