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Linking boundaries: adaptable notion of homeBewza, Amber 05 April 2012 (has links)
This interior design practicum is the design of three floating houses located on Granville Island, Vancouver, British Columbia. They are spatially efficient and aid in human-nature connections through the manipulation of thresholds. The adaptation of small spaces is best accomplished through the use of multifunctional space, efficient storage, and manipulation of views. Linking of spaces and the blurring of thresholds is best accomplished through the use of implied axial linkage to the exterior and through the addition of ornament. The human-nature connection, or biophilic design, is best accomplished through the integration of direct, indirect, and symbolic experiences with the natural environment. This is accomplished through the variation of ceiling heights, linking internal and external views, integration of natural light, and use of natural materials that vary in texture and reflectance value.
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On designing coarse grain reconfigurable arrays to operate in weak inversionRoss, Dian Marie 17 December 2012 (has links)
Field Programmable Gate Arrays (FPGAs) support the reconfigurable computing paradigm by providing an integrated circuit hardware platform that facilitates
software like reconfigurability. The addition of an embedded microprocessor and peripherals to traditional FPGA Combinational Logic Blocks (CLBs) interleaved with
interconnections has effectively resulted in a programmable system on-chip. FPGAs
are used to support flexible implementations of Application Specific Integrated Circuit (ASIC) functions. Because FPGAs are reconfigurable, they often are used in
place of ASICs during the cicuit design process. FPGAs are also used when only a
small number of ICs are required: ASICs necessitate large manufacturing runs to be
economically viable; for smaller runs the use of FPGAs is an economic alternative.
Application domains of interest, such as intelligent guidance systems, medical
devices, and sensors, often require low power, inexpensive calculation of trance-
dental functions. COordinate Rotation DIgital Computer (CORDIC) is an iterative algorithm used to emmulate hardware expensive multipliers, such as Multiply/ACculmulate (MAC) units, with only shift and add operations. However, because CORDIC is a sequential algorithm, characterized as having the latency of a
serial multiplier, techniques that speed up computational performance have many
applications.To this end, three implementations of standard CORDIC, (i) unrolled hardwired,
(ii) unrolled programmable, and (iii) rolled programmable, were implemented on four
Xilinx FPGA families: Virtex-4, -5, and -6, and Spartan-6. Although hardwired
unrolled was found to have the greatest speed at the expense of no runtime flexibility,
and rolled programmable was found to have the greatest flexibility and lowest silicon
area consumption at the expense of the longest propagation delay, improvements to
CORDIC implementations were still sought.
Three parallelized CORDIC techniques, P-CORDIC, Flat-CORDIC, and
Para-CORDIC, were implemented on the same four FPGA families. P-CORDIC
and Flat-CORDIC, were shown to have the lowest latency under various conditions;
Para-CORDIC was found to perform well in deeply pipelined, high throughput circuits. Design rules for when to use standard versus precomputation CORDIC techniques are presented.
To address the low power requirements of many applications of interest, the Unfolded Multiplexor-LRB (UMUX-LRB), patent held by Sima, et al, was analyzed in
weak inversion across four transistor technology nodes (180nm, 130nm, 90nm, and
65nm). Previous was also expanded from strong inversion across 180nm, 130nm, and
90nm technology nodes to also include 65nm.
The UMUX-LRB interconnection network is based upon the Xilinx commercial
interconnection network. Therefore, this network (MUX-LRB), and another static
circuit technique, CMOS-Transmission Gates (CMOS-TG), were profiled across all
four technology nodes to provide a baseline of comparision. This analysis found
the UMUX-LRB to have the smallest and most balanced rising and falling edge
propagation delay, in addition to having the greatest reliability for temperature and
process variation. / Graduate
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Processing of Tactile Stimuli in Children with Tourette Syndrome and Attention Deficit Hyperactivity Disorder: An ERP InvestigationNeedham, Allison Carissa 16 July 2013 (has links)
Purpose: To investigate and characterize sensory sensitivity in Tourette syndrome (TS) through an evaluation of behaviour, perception and processing of tactile stimuli in children with TS and co-morbid Attention Deficit Hyperactive Disorder (ADHD) compared to typically developing controls (TDC). Methods: Somatosensory evoked P3 potentials were recorded in TS+ADHD and in TDC children aged 6-12 and compared at midline electrodes. Reported sensory sensitivity was
measured using the Sensory Profile, while Semmes-Weinstein filaments were used to determine tactile threshold in the same area stimulated during P3 testing. Results: 13 TS+ADHD and 12 TDC were studied. TS+ADHD children reported significantly higher sensory sensitivity (p=.001) and demonstrated a significantly lower tactile threshold (p=.027) than TDC. Furthermore, the amplitude of electrophysiological responses to repetitive tactile stimuli was significantly larger in TS+ADHD (p=.0009).
Conclusion: TS+ADHD children are significantly more sensitive to tactile stimulation than controls. ERP differences suggest that central processing alterations could mediate sensory
hypersensitivity.
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Processing of Tactile Stimuli in Children with Tourette Syndrome and Attention Deficit Hyperactivity Disorder: An ERP InvestigationNeedham, Allison Carissa 16 July 2013 (has links)
Purpose: To investigate and characterize sensory sensitivity in Tourette syndrome (TS) through an evaluation of behaviour, perception and processing of tactile stimuli in children with TS and co-morbid Attention Deficit Hyperactive Disorder (ADHD) compared to typically developing controls (TDC). Methods: Somatosensory evoked P3 potentials were recorded in TS+ADHD and in TDC children aged 6-12 and compared at midline electrodes. Reported sensory sensitivity was
measured using the Sensory Profile, while Semmes-Weinstein filaments were used to determine tactile threshold in the same area stimulated during P3 testing. Results: 13 TS+ADHD and 12 TDC were studied. TS+ADHD children reported significantly higher sensory sensitivity (p=.001) and demonstrated a significantly lower tactile threshold (p=.027) than TDC. Furthermore, the amplitude of electrophysiological responses to repetitive tactile stimuli was significantly larger in TS+ADHD (p=.0009).
Conclusion: TS+ADHD children are significantly more sensitive to tactile stimulation than controls. ERP differences suggest that central processing alterations could mediate sensory
hypersensitivity.
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Effects of Habitat Characteristics on Occupancy and Productivity of a Forest-Dependent Songbird in an Urban LandscapeRobinson, Dianne Hali 03 October 2013 (has links)
Habitat fragmentation and isolation can result in decreased occupancy and reproductive success within songbirds, particularly for species inhabiting urban environments where suitable habitat may be limited. The golden-cheeked warbler (Setophaga chrysoparia) is a federally endangered songbird that inhabits oak-juniper (Quercus spp.- Juniperus spp.) across central Texas. Past research on this warbler has indicated decreased patch occupancy near urban areas and negative reproductive effects associated with decreased distance to edge and decreased canopy cover. A rural study indicated warblers occupy patches ≥3 ha, and warblers in patches ≥20 ha are more likely to successfully fledge young. There are no thresholds yet identified for this warbler within urban environments, where effects of habitat fragmentation on reproductive success are more pronounced than within rural environments. I monitored patch occupancy, territory establishment, pairing success, and fledging success of warblers in an urban environment. I determined minimum patch-size thresholds for productivity measurements, and also monitored effects on productivity from canopy cover, woodland composition, distance to and size of the nearest habitat patch, and distance to the nearest habitat patch >100 ha. I compared my results to those from a similar study conducted in a rural system. I compared territory size and territory density between an urban and rural system. Warblers occupied 24% (n = 63) patches surveyed; the smallest patch occupied was 3.5 ha. The smallest patch with an established territory was 10.7 ha, and 10% (n = 63) of habitat patches had at least one established territory. Warblers successfully fledged young in 3 patches, the smallest of which was 26.5 ha. I found patch-size was predictive for territory establishment and pairing success with warblers requiring 13 ha (95% CI: 10.0 – 16.8 ha) and 19 ha (95% CI: 15.7 – 22.6 ha) habitat patches, respectively. I found a minimum threshold of approximately 66% canopy cover (95% CI: 65.2 – 66.4%) required for patch occupancy, and found no warblers established a territory in a habitat patch >25 m from the next nearest patch. I found higher minimum thresholds within an urban system for territory establishment and pairing success than those seen within a rural system. I suggest preserving warbler habitat patches >22 ha that are in close proximity to other habitat patches. This will help to enhance warbler habitat within urban areas and maintain reproductively viable habitat patches, while not halting development completely.
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A Combination of Eccentric Muscle Exercise and Repeated Cold Stress (RCS) Induced Prolonged Hyperalgesia : An Attempt to Develop an Animal Model of Chronic Muscle PainTAGUCHI, Toru, SATO, Jun, MIZUMURA, Kazue 12 1900 (has links)
国立情報学研究所で電子化したコンテンツを使用している。
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A study of multifold Euclidean geometry codesYiu, Kai-Ping January 1974 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1974. / Bibliography: leaves [112]-114. / iv, 114 leaves
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Olfactory Function : The Influence of Demographic, Cognitive, and Genetic FactorsHedner, Margareta January 2013 (has links)
Olfactory function is affected by demographic, cognitive, and genetic factors. In the present thesis, three empirical studies investigated individual differences in olfactory ability. Study I explored demographic and cognitive correlates in common olfactory tasks; odor detection, odor discrimination, and odor identification. The results indicated that old age influenced performance negatively in all tasks, and that semantic memory proficiency and executive functioning were related to odor discrimination and odor identification performance. No cognitive influence was observed for measurements of olfactory threshold. Using population-based data, Study II investigated a potential influence of the ApoE gene on olfactory identification after controlling for health status, semantic memory, and preclinical and clinical dementia. The main finding was that the ApoE- ɛ4 allele interacted with age, such that older ɛ4-carriers had an impaired odor identification performance relative to older non-carriers. Importantly, the negative ApoE- ɛ4 effect on olfactory proficiency was independent of clinical dementia conversion within five years. Study III investigated the effects of the BDNF val66met polymorphism on olfactory change over a five-year interval, in a community dwelling sample of young and old age cohorts. The results showed that age-related decline in olfactory identification was influenced by the BDNF val66met. In middle-aged subjects, no effect of BDNF val66met was observed although older val homozygote carriers showed a selectively larger olfactory decline than the older met carriers. Overall, results suggest that the relative influence of demographic and cognitive factors vary across different olfactory tasks and that two genes (ApoE and BDNF) impact age-related deficits in odor identification. Potential theoretical and practical implications of the findings are discussed as well as potential limitations of association studies in genomics research.
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Spatial perception and progressive addition lensesHendicott, Peter Leslie January 2007 (has links)
Progressive addition lenses (PALs) are an increasingly preferred mode for the correction of presbyopia, gaining an increased share of the prescription lens market. Sales volumes are likely to increase over the next few years, given the increasing cohort of presbyopic patients in the population. This research investigated adaptation to PAL wear, investigating head movement parameters with and without progressive lenses in everyday visual tasks, and examined symptoms of spatial distortions and illusory movement in a crossover wearing trial of three PAL designs. Minimum displacement thresholds in the presence and absence of head movement were also investigated across the lens designs. Experiment 1 investigated head movements in two common visual tasks, a wordprocessing copy task, and a visual search task designed to replicate a natural environment task such as looking for products on supermarket shelving. Head movement parameters derived from this experiment were used to set head movement amplitude and velocity in the third experiment investigating minimum displacement thresholds across three PAL designs. Head movements were recorded with a Polhemus Inside Track head movement monitoring system which allows real time six degrees of freedom measurement of head position. Head position in azimuth, elevation and roll was extracted from the head movement recorder output, and data for head movement angular extent, average velocity (amplitude/duration) and peak velocity were calculated for horizontal head movements Results of the first experiment indicate a task dependent effect on head movement peak and average velocity, with both median head movement average and peak velocity being faster in the copy task. Visual task and visual processing demands were also shown to affect the slope of the main sequence of head movement velocity on head movement amplitude, with steeper slope in the copy task. A steeper slope, indicating a faster head movement velocity for a given head movement amplitude, was found for head movements during the copy task than in the search task. Processing demands within the copy task were also shown to affect the main sequence slopes of velocity on amplitude, with flatter slopes associated with the need for head movement to bring gaze to a specific point. These findings indicate selective control over head movement velocity in response to differing visual processing demands. In Experiment 2, parameters of head movement amplitude and velocity were assessed in a group of first time PAL wearers. Head movement amplitude, average and peak velocity were calculated from head movement recordings using the search task, as in Experiment 1. Head movements were recorded without PALs, on first wearing a PAL, and after one month of PAL wear to assess adaptation effects. In contrast to existing literature, PAL wear did not alter parameters of head movement amplitude and velocity in a group of first time wearers either on first wearing the lenses or after one month of wear: this is due to task related effects in this experiment compared to previous work. Task demand in this experiment may not have required wearers to use the progressive power corridor to accomplish identification of visual search targets, in contrast to previous studies where experimental conditions were designed to force subjects to use the progressive corridor. In Experiment 3, minimum displacement thresholds for random dot stimuli were measured in a repeated measures experimental design for a single vision lens as control, and three PAL designs. Thresholds were measured in central vision, and for two locations in the temporal peripheral field, 30° temporal fixation and 10° above and below the horizontal midline. Thresholds were determined with and without the subjects' head moving horizontally in an approximate sinusoidal movement at a frequency of about 0.7 Hz. Minimum displacement thresholds were not significantly affected by PAL design, although thresholds with PALs were higher than with a single vision lens control. Head movement significantly increased minimum displacement threshold across lens designs, by a factor of approximately 1.5 times. Results indicate that the local measures of minimum displacement threshold determined in this experiment are not sensitive to lens design differences. Sensitivity to motion with PAL lenses may be more a global than a localized response. For Experiment 4, symptoms of spatial distortion and illusory movement were investigated in a crossover wearing trial of three PAL designs, and related to optical characteristics of the lenses. Peripheral back vertex powers of the PALs were measured at two locations in the right temporal zone of the lenses, 15.6 mm temporal to the fitting cross, and 2.7 m above and below the horizontal to the fitting cross. These locations corresponded to the zones of the lenses through which minimum displacement thresholds were measured in the previous experiment. The effect of subjects' self movement on symptoms is able to discriminate between PAL designs, although subjective symptoms alone were not related to the lens design parameters studied. Subjects' preference for one PAL design over the other designs studied in this experiment is inversely related to the effect on subject movement on their symptoms of distortion. An optical parameter, blur strength, derived from the power vector components of the peripheral powers, may indicate preference for particular PAL designs, as higher blur strength values are associated with lower lens preference scores. Head movement amplitude and velocity are task specific, and are also influenced by visual processing demands within tasks. PALs do not affect head movement amplitude and velocity unless tasks are made demanding or performed in less natural situations designed to influence head movement behaviour. Both head movement and PALs have large effects on minimum displacement thresholds; these effects may be due in part to complexity of the subjects' task within the experiment. Minimum displacement thresholds however were not influenced by PAL design. The most sensitive indicator for subject's preference of PALs was the effect of subjects' self movement on their perception of symptoms, rather than the presence of actual symptoms. Blur strength should be further investigated for its role in PAL acceptance.
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Complete numerical solution of electron-hydrogen collisionsbartlett@fizzy.murdoch.edu.au, Philip Lindsay Bartlett January 2005 (has links)
This thesis presents an extensive computational study of electron-impact scattering and ionisation of atomic hydrogen and hydrogenic ions, which are fundamental to many diverse disciplines, from astrophysics and nuclear fusion to atmospheric physics. The non-relativistic Schrodinger equation describes these collisions, though finding solutions for even hydrogen, the simplest electron-atom collision, has proven to be a monumental task. Recently, Rescigno et al [Science 286, 2474 (1999)] solved this equation in coordinate space using exterior complex scaling (ECS), and presented the first electron-hydrogen differential cross sections for ionisation that matched with experiment without requiring uncontrolled approximation. This method has significant potential for extension to larger collision systems, but its large computational demand has limited its energy range and target configurations, and its application to discrete final-state collisions has been largely unexplored.
Using radically different numerical algorithms, this thesis develops methods that improve the computational efficiency of ECS by two orders of magnitude. It extends the method to calculate discrete final-state scattering cross sections and enhances the target description to include hydrogenic ions and excited initial states. In combination, these developments allow accurate solutions over a broad range of energies and targets, for both scattering and ionisation, including the important near-threshold energy region where accurate calculations have been unavailable. The refined ECS method implemented in this work now offers complete numerical solutions of electron-hydrogen collisions, and its computational efficiency will facilitate its future application to more complex targets. The thesis culminates with the first ab initio quantum mechanical confirmation of ionisation threshold laws for electron-hydrogen collisions [Bartlett and Stelbovics, 2004, Phys. Rev. Lett. 93, 233201], which have resisted confirmation through the complete solution of the Schrodinger equation for more than half a century.
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