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As part of the Composite Technology for Exploration (CTE) project at NASA, woven fabric composites are being investigated for their use in Space Launch System (SLS) hardware. Composites are more difficult to analyze than isotropic materials and require more complex methods for predicting failure. NASA is seeking a method for predicting the damage initiation and propagation of woven fabric composites in order to utilize these materials effectively in SLS hardware. This work focuses on notched woven fabric composites under tensile loading. An analytical model consisting of a macro-level failure criterion and damage propagation was developed and implemented in explicit finite element analysis to simulate woven composite materials. Several failure criteria and propagation models were investigated and compared. A response surface was used to better understand the effects of damage parameters on the failure load of a specimen. The model chosen to have best represented the physical specimen used the Tsai-Wu failure criterion. Additional physical tests are needed to further validate the model. / Master of Science / A composite material consists of two or more different materials that are joined together to form a new material with improved properties. Woven fabric composites weave strips of fibers and a bonding material into a pattern to increase the material’s ability to withstand loads in various directions. NASA is seeking a method to predict the conditions under which woven fabric composites will break. A greater understanding of the capabilities of woven fabric composites will help NASA improve the structures involved in space exploration. This work attempts to build an analytical model that can predict the loads under which a woven fabric composite will break in tension. Several different analytical theories were used to model a woven fabric composite and the results were compared with lab tests. One of the theories, the Tsai-Wu failure criterion, was selected as the best representation of the physical specimen. Further additional physical tests are necessary to further validate the analytical model.

CARPET is a mystery, It is not just woven one knot after the other It is a POEM, written one word after the other A SONG, composed one note after the other A PAINTING, done one color after the other A WALL, stacked one brick after (on) another. My architectural thesis began with the question of the relationship between the realm of the world most ancient craft and craft of building : The textile art and architecture. Two branches of art which are said their inventions coincide with each other and both came from the same origin : a pen (fence),an interwoven partition. The question of thesis led me to start my research on textile arts and weaving in particular which first became a problematic quest, since the remnants of the textile products, which are still to be found diffuse almost everywhere,have only very recently started to attract attention and the existing information pertained to their history or complex technical aspects of this branch will not suffice the profound need of surveying on textiles. The Carpet Museum will become a shelter for the preservation of this ephemeral craft, protecting this forgotten branch of art. The art of weaving has always been presented within art collections that include other decorative/technical arts, without having a well-deserved position for itself. I began the thesis by weaving : I wove a small piece of rug to explore architecture through the structure of carpets, textiles and weaving. In the design of the carpet museum,each building element such as bearing wall,window,stair,ceiling or sitting area became an architectural manifestation of a woven craft. / Master of Architecture

Over the past few years, many high performance asynchronous transfer mode (ATM) switches have been proposed. The majority of these switches have high performance but also high hardware complexity. Therefore, there is a need for switch designs with low complexity and high performance. This research proposes three new ATM switches based on the folded hypercube network (FHC). The performance of the three architectures are studied using a network model and simulation. The major performance parameters measured are the cell loss rate and cell delay time through the switch under uniform, normal, and bursty traffic patterns. To guarantee faster switching of time-sensitive cells, the routing algorithm of the three switches uses a priority scheme that gives higher precedence to the time-sensitive cells. Also, an output buffer controller is designed to manage the buffers in a fair manner. The three proposed switch architectures have lower complexity while providing equivalent or better switching performance compared to other more complex ATM switches described in the literature. This research shows a new approach to designing ATM switches by using the FHC as the switching fabric for the first time instead of using the crossbar, multi-path, or Banyan-based switching fabrics. / Ph. D.

There are two inter-related parts to the hypothesis explored in this research. The first is that it is significant to employ fabric as a medium in a fine art context, and the second aspect argues that female artists who choose fabric as their medium should be recognised as 'artists' rather than as crafts practitioners. I propose that in choosing fabric as a medium and sewing as my method of making art, I am working within the framework of contemporary fine art practice. In his essay 'To Cut is to Think' Germano Celant succinctly described the 'cut' made by artists who choose cutting as their process: The cut of the scissor is like the click of a camera or the whirr of a movie camera, like a stroke of the pencil or paintbrush: all these acts decisively isolate a form or representation, marking a surface that generates a reality. The cut puts an end to the traditional representation of the image, dissolving it and then restoring it as a testimony to the artist's vision and understanding. In this light, the cut confers meaning, and its use unites artists, photographers, designers and tailors, who cut their visions from the magma of their materials, whether these be colour or bronze, fabric or film, metal or wool, wood or canvas (1996, p. 31). My own use of the cut, as the bespoke tailor, reinterpreted fabric as paint and utilized pinstriped fabric as a visual metaphor for relationships of power, pink satin as a symbol of the female inclusion and Frank Stella's Black Paintings as a tool to position my work. Therefore, I would claim that I am working towards a conceptual repositioning of fabric as a medium in fine art.

This thesis presents a model of fabric bending hysteresis. The hysteresis model is designed to reproduce the fabric bending measurements taken by the Kawabata Evaluation System (KES) and the model parameters can be derived directly from these property measurements. The advantage to using this technique is that it provides the ability to simulate a continuum of property curves. Results of the model and its components are compared and constrasted with experimental results for fabrics composed of different weaves and yarn types. An attempt to incorporate the bending model as part of a fabric drape simulation is also made.

A new approach to local nonlinear image restoration is described, based on approximating functions using a regular grid of points in a many-dimensional space. Symmetry reductions and compression of the sparse grid make it feasible to work with twelve-dimensional grids as large as 22¹². Unlike polynomials and neural networks whose filtering complexity per pixel is linear in the number of filter co-efficients, grid filters have O(1) complexity per pixel. Grid filters require only a single presentation of the training samples, are numerically stable, leave unusual image features unchanged, and are a superset of order statistic filters. Results are presented for additive noise, blurring, and superresolution.

An automatic question answering system must find, within a corpus,short factual answers to questions posed in natural language. The process involves analyzing the question, retrieving information related to the question, and extracting answers from the retrieved information. This thesis presents a novel approach to answer extraction in an automated question answering (QA) system. The answer extraction approach is an extension of the MultiText QA system. This system employs a question analysis component to examine the question and to produce query terms for the retrieval component which extracts several document fragments from the corpus. The answer extraction component selects a few short answers from these fragments. This thesis describes the design and evaluation of the Redundant Inverse Term Frequency (RITF) answer extraction component. The RITF algorithm locates and evaluates words from the passages that are likely to be associated with the answer. Answers are selected by finding short fragments of text that contain the most likely words based on: the frequency of the words in the corpus, the number of fragments in which the word occurs, the rank of the passages as determined by the IR, the distance of the word from the centre of the fragment, and category information found through question analysis. RITF makes a substantial contribution in overall results, nearly doubling the Mean Reciprocal Rank (MRR), a standard measure for evaluating QA systems.

A new approach to local nonlinear image restoration is described, based on approximating functions using a regular grid of points in a many-dimensional space. Symmetry reductions and compression of the sparse grid make it feasible to work with twelve-dimensional grids as large as 22¹². Unlike polynomials and neural networks whose filtering complexity per pixel is linear in the number of filter co-efficients, grid filters have O(1) complexity per pixel. Grid filters require only a single presentation of the training samples, are numerically stable, leave unusual image features unchanged, and are a superset of order statistic filters. Results are presented for additive noise, blurring, and superresolution.

This thesis presents a model of fabric bending hysteresis. The hysteresis model is designed to reproduce the fabric bending measurements taken by the Kawabata Evaluation System (KES) and the model parameters can be derived directly from these property measurements. The advantage to using this technique is that it provides the ability to simulate a continuum of property curves. Results of the model and its components are compared and constrasted with experimental results for fabrics composed of different weaves and yarn types. An attempt to incorporate the bending model as part of a fabric drape simulation is also made.