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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

1219 Colorado

Spaw, Christopher Alan January 1900 (has links)
Masters of Architecture / Landscape Architecture/Regional and Community Planning / 1219 Colorado is the documentation of the nonlinear process of design as it applies to the reconfiguration of a residential dwelling. This process is illustrated through a collection of sketches, design drawings, construction documents and images produced from 1999 to 2005. 1219 Colorado investigates materiality the physical substance of architecture, as well as the nature of thoughtful connection physical and theoretical through the process of making. The need to build, to make, to design, and explore is what drives the process. While the space of architecture is most often designed and perceived as lines on paper, it is through the making of physical models that the creative act of discovery reveals its greatest potential. The process explores the design of a model constructed at full-scale. No longer representational, the study is the product; the materials and methods are genuine. This process differs from the process of building in that the intention is no longer to construct only that which is designed. Rather the challenge is to explore beyond the design, reveal new possibilities, refine design decisions, and most importantly to take advantage of unforeseen opportunities that are revealed through the act of making. The scope of the task expanded periodically as a function of increasing knowledge of construction, declining acceptance of the quality of the existing condition and in order to accommodate an evolving set of programmatic requirements. To date the construct has under gone no less than three different design schemes, and a fourth will follow as the process continues to be refined and reconsidered. The project continues to evolve, grow, and change directions. 1219 Colorado explores design is not a linear process. Architecture is not always pretty.
2

08 Scale Model Building Demo and Tips

Taylor, Jonathan 01 January 2022 (has links)
https://dc.etsu.edu/theatre-videos-oer/1008/thumbnail.jpg
3

Design of an Experimental Mine Simulator for the Development of a Procedure for Utilization Multiple Tracer Gases in Underground Mines

Bowling, John Robert Reid 01 June 2011 (has links)
An experimental mine simulator was constructed which will be used to conduct tracer gas experiments in the laboratory. The test apparatus simulates a mine in a tabular deposit and is modular and simple and can be easily rearranged to represent a variety of mine geometries. The apparatus is appropriate for the use of tracer gases by being both airtight and open-circuit (exhausting to the atmosphere) and by maintaining turbulent flow throughout the model, ensuring the tracer gas is fully dispersed. The model features ports for injection and sampling of tracer gases, which represent boreholes present in an actual mine. The model is designed, in part, for the practice of tracer gas release and sampling methods in the laboratory. Valves on the apparatus represent ventilation controls, such as stoppings or regulators, or changing resistances in a mine, such an increase in resistance due to a roof fall or a decrease in resistance due to stoppings being destroyed. The relative resistances of airways can be changed by changing the status of the valves to represent different states of the ventilation controls. The mine simulator should serve as a tool for identifying and investigating novel tracer gases, developing a procedure for performing ventilation surveys using multiple tracer gases, and eventually developing a method for remotely inferring ventilation changes using tracer gases. / Master of Science
4

Modelling of subgrid-scale stress and passive scalar flux in large eddy simulations of wall bounded turbulent flows

Marstorp, Linus January 2008 (has links)
The aim of the thesis is to develop and validate subgrid-scale models that are relevant for large eddy simulations of complex flows including scalar mixing. A stochastic Smagorinsky model with adjustable variance and time scale is developed by adding a stochastic component to the Smagorinsky constant. The stochastic model is shown to provide for backscatter of both kinetic energy and scalar variance without causing numerical instabilities. In addition, new models for the subgrid-scale stress and passive scalar flux are derived from modelled subgrid scale transport equations. These models properly account for the anisotropy of the subgrid scales and have potentials wall bounded flows. The proposed models are validated in wall bounded flows with and without rotation and show potential or significantly improve predictions for such cases. / <p>QC 20100826</p>
5

Multi-scale whole-plant model of Arabidopsis growth to flowering

Chew, Yin Hoon January 2013 (has links)
In this study, theoretical and experimental approaches were combined, using Arabidopsis as the studied species. The multi-scale model incorporates the following, existing sub-models: a phenology model that can predict the flowering time of plants grown in the field, a gene circuit of the circadian clock network that regulates flowering through the photoperiod pathway, a process-based model describing carbon assimilation and resource partitioning, and a functional-structural module that determines shoot structure for light interception and root growth. First, the phenology model was examined on its ability to predict the flowering time of field plantings at different sites and seasons in light of the specific meteorological conditions that pertained. This analysis suggested that the synchrony of temperature and light cycles is important in promoting floral initiation. New features were incorporated into the phenology model that improved its predictive accuracy across seasons. Using both lab and field data, this study has revealed an important seasonal effect of night temperatures on flowering time. Further model adjustments to describe phytochrome (phy) mutants supported the findings and implicated phyB in the temporal gating of temperature-induced flowering. The improved phenology model was next linked to the clock gene circuit model. Simulation of clock mutants with different free-running periods highlighted the complex mechanism associated with daylength responses for the induction of flowering. Finally, the carbon assimilation and functional-structural growth modules were integrated to form the multi-component, whole-plant model. The integrated model was successfully validated with experimental data from a few genotypes grown in the laboratory. In conclusion, the model has the ability to predict the flowering time, leaf biomass and ecosystem exchange of plants grown under conditions of varying light intensity, temperature, CO2 level and photoperiod, though extensions of some model components to incorporate more biological details would be relevant. Nevertheless, this meso-scale model creates obvious application routes from molecular and cellular biology to crop improvement and biosphere management. It could provide a framework for whole-organism modelling to help address global issues such as food security and the energy crisis.
6

The Development of Self-action Control Questionnaire

Tsai, Chu-Chu 09 August 2012 (has links)
The purpose of this study s to construct a questionnaire about Self-action control of Academic Performance for college students based on Kuhl and Kraska (1989) action control theory. The sampling method of this study used purposive sampling, randomly selected from the freshman or sophomore students to various departments of Sun Yat-sen University, with a total of 409 examinees. After four expert validity, experts on the appropriateness of the questionnaire with content review and suggest modifications to draw the contents of the pre-test about 78 items . Measuring method is adopted online computer systems connection randomly selected to scale the three dimensions of 10 questions given to the college students. The contents of the Scale have three dimensions, pre-analysis of the results of the RSM mode in the ConQuest software, there are 11 questions beyond the adaptation target range, and finally the good adaptation of Formal items are 67 items. The overall item difficulty is too easy. The results of the three sub-scale reliability are 0.62, 0.65 and 0.53. Based on the findings, it is recommended more difficult items can be included to the questionnaire in the future. developed.
7

Subgrid-scale modelling for large-eddy simulation invluding scalar mixing in rotating turbulent shear flows

Marstorp, Linus January 2006 (has links)
<p>The aim of the present study is to develop subgrid-scale models that are relevant for complex flows and combustion. A stochastic model based on a stochastic Smagorinsky constant with adjustable variance and time scale is proposed. The stochastic model is shown to provide for backscatter of both kinetic energy and scalar variance without causing numerical instabilities. A new subgrid-scale scalar flux model is developed using the same kind of methodology that leads to the explicit algebraic scalar flux model, EASFM, for RANS. The new model predicts the anisotropy of the subgrid-scales in a more realistic way than the eddy diffusion model. Both new models were tested in rotating homogeneous shear flow with a passive scalar. Rogallo’s method of moving the frame with the mean flow to enable periodic boundary conditions was used to simulate homogeneous shear flow.</p>
8

Influence of Foundation Stiffness on Reinforced Soil Wall

Ezzein, Fawzy Mohammad 02 November 2007 (has links)
The influence of yielding foundations on the mechanical behaviour of reinforced soil walls including wall deformations and loads (strains) in the reinforcement layers is very complex. Based on a review of the literature, there is a need to quantify and isolate the influence of foundation boundary type and magnitude of foundation stiffness on deformations and reinforcement loads in geosynthetic reinforced soil walls. This thesis presents the results of a series of 1/6-scale reinforced soil wall model tests that were carried out to examine the influence of horizontal and vertical toe compliance and vertical foundation compressibility on wall behaviour. The heavily instrumented walls were constructed in a strongbox that was 1.2 m high by 1.6 m wide and retained soil to a distance of 2.3 m behind the facing. The models were uniformly surcharged in stages following construction. The experimental program consisted of three groups of tests. Group 1 tests involved five walls. One wall was constructed with a very stiff horizontal restraint, and three walls were constructed with different horizontal toe stiffness using combinations of coiled springs. The remaining wall in this series was constructed without any horizontal toe restraint. Group 2 was comprised of three walls. One wall was a control wall with a rigid toe. The other two walls were constructed with different vertical toe stiffness support using different combinations of rubber blocks. Group 3 included a control wall with a rigid foundation and a companion wall constructed with a compressible foam and rubber layers below the backfill soil and the wall facing. The results demonstrate that the quantitative behaviour of the models was affected by the type and magnitude of foundation stiffness. For example, as horizontal toe stiffness increased a greater portion of the total horizontal earth load against the wall facing was carried by the toe. The data showed that the shape of facing lateral deformation profiles changed from rotation about the toe for the case of a very stiff horizontal toe to a more uniform profile for the unrestrained toe case. For the case of a rigid vertical footing support below the facing, vertical toe loads were greater than those computed from facing self-weight alone due to down-drag forces developed at the facing–reinforcement connections as the wall facing moved outward. As vertical toe support stiffness decreased with respect to foundation compressibility below the soil backfill, the magnitude of soil down-drag forces diminished resulting in a decrease in vertical toe load. / Thesis (Master, Civil Engineering) -- Queen's University, 2007-10-27 12:15:56.027
9

Measurement of NMR flow propagators and local numerical analysis of dual scale porous media

Zheng, Yong, Shikhov, Igor, d'Eurydice, Marcel N., Arns, Christoph 11 September 2018 (has links)
Flow propagators have been frequently used in characterisation of porous media and the study of fluid transport behaviour. Previous work considered the shape of measured flow propagators using Nuclear Magnetic Resonance (NMR) discussed the influence of pore geometry, dispersion, relaxation and internal gradients. In addition, numerically simulated flow propagators were also reported. However, a uantitative numerical analysis of local contributions to flow propagators has not been considered in the literature, yet may provide significant new insights into the flow behaviour through complex porous media. In this work we use two types of beads to realize a dual-scale bead pack consisting of micro- and macropore regions for the NMR experiments. A low-field NMR system (2 MHz) was used to measure flow propagators for this sample. We further generated a dual-scale Gaussian Random Field (GRF) image based on porosity, beads diameters and volume fraction of each type of bead for numerical simulations. A Lattice Boltzmann Method (LBM) and Random Walk (RW) technique were combined to derive the simulated flow propagators and validated against experiments. We carry out a local analysis of the flow propagators showing a significant difference in bandwidth of displacements in micro- and macro-pore regions. In addition, the local flow propagators indicate a linear relationship between mixing (the fluid exchange on regions' boundaries) and flow velocities as well as a non-linear correlation between mixing and evolution times.
10

Microstructural Effects on the Effective Piezoelectric Responses of Additively Manufactured Triply Periodic Co-Continuous Piezocomposites

Yang, Wenhua 10 August 2018 (has links)
Triply Periodic Co-continuous piezocomposites, which consist of a ferroelectric-ceramic phase and an elastic-polymer phase continuously interconnected in three dimensions (3D), are emerging flexible piezoelectric materials with high efficiency in absorbing and converting multi-directional mechanical stimuli into electrical signals. Current co-continuous piezocomposites cannot be achieved with controlled piezoelectric properties due to the limited capability of traditional fabrication methods in carefully controlling the morphology of each phase, additive manufacturing such as Suspension-Enclosing Projection-Stereolithography process thus was selected. Porous ceramic skeleton with randomly distributed grain size is commonly observed in sintered ceramic skeleton fabricated by additive manufacturing. The effective piezoelectric properties of the piezocomposites were thus studied utilizing a two-scale method. Through analyzing the simulated results of different process parameters, optimal parameters of 3D printing processes including post-processes was subsequently suggested.

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