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- Resource Type:
- Report
- Creator:
- Lowry, Kelly
- Abstract:
- The growing interest in the long-term performance of pile foundations and their ability to resist the negative effects of water exposure and aggressive soils has led to considering non-corrosive materials such as fibre-reinforced polymer (FRP). The most common applications are light-bearing structures in waterfront environments, while applications for larger structures have not been widely accepted in industry due to the lack of long-term records and design guidelines available. Previous research has primarily focused on the load transfer of concrete-filled FRP tubes—making it difficult to quantify the performance of FRP as a piling material on its own. In this study, a numerical model using the finite element method was developed to simulate small-scale load tests of hollow carbon-fibre reinforced polymer (CFRP) and glass-fibre reinforced polymer (GFRP) piles in soft clay. Verification of the model was attained using results from axial and lateral load tests on small-scale hollow CFRP and GFRP piles and pile-soil interaction was modelled using experimental data from interface shear tests conducted at Carleton University. A parametric analysis was performed to investigate and determine the key factors that influence the axial and lateral load response of hollow FRP piles. The findings of this research indicate that the number of FRP layers impacts loading behaviour significantly, while inner tube soil height has a reasonable influence on axial load response and fibre orientation has a minor effect under lateral load conditions.
- Date Created:
- 2022-12-23
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- Resource Type:
- Research Paper
- Creator:
- Pettie, Jasmin
- Abstract:
- The purpose of this study was to explore the question of why women are still so underrepresented in Canadian federal politics and specifically within the Canadian House of Commons despite advances in representation in many other fields. To answer this question a study was conducted using qualitative data obtained from interviews with 17 female Members of the 42nd Parliament of Canada between October 2018 to April 2019. Data collected through these interviews was analyzed qualitatively using a combination of content and discourse analysis to summarize, categorize, and investigate the verbal, written, and behavioural data that was obtained. Findings from this study mostly confirm the findings of previous research with a few key exceptions. New findings from this study include that a more nuanced relationship exists between female MP’s and the media than previously thought; that most of the women who run for office at the federal level have very little or no knowledge of the nomination, candidate, and electoral process before they start; and that a toxic work place culture exists within the House of Commons and this negatively impacts the experience that female MP’s have and is one of the reasons women are more likely to have shorter political terms and leave politics after shorter amounts of time when compared to their male counterparts.
- Date Created:
- 2019-10-16
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- Resource Type:
- Article
- Creator:
- Panchen, Zoe A. and Gorelick, Root
- Abstract:
- In temperate regions, there are clear indications that spring flowering plants are flowering earlier due to rising temperatures of contemporary climate change. Temperatures in temperate regions are rising predominantly in spring. However, Arctic regions are seeing unprecedented temperature increases, predominantly towards the end of the growing season. We might, therefore, expect to see earlier flowering of later-season flowering Arctic plants. Parks Canada has been monitoring purple saxifrage (Saxifraga oppositifolia) and mountain avens (Dryas integrifolia) flowering and fruiting times for 20 years at Tanquary Fiord, Qut- tinirpaaq National Park, Ellesmere Island. Saxifraga oppositifolia flowers in early spring, while D. integrifolia flowers in midsummer. Over the 20-year period, Tanquary Fiord’s annual and late-summer temperatures have risen significantly. During the same timeframe, D. integrifolia showed a trend towards earlier flowering and fruiting, but S. oppositifolia showed no changes in flowering or fruiting time. Flowering time was related to monthly temperatures just prior to flowering. The number of flowers produced was related to the previous autumn’s monthly temperatures. We found no relationship between flowering time and snowmelt date. Our findings suggest that Arctic community level ecological effects from climate change induced phenology changes will differ from those in temperate regions.
- Date Created:
- 2016-05-17
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- Resource Type:
- Article
- Creator:
- Millard, Koreen and Richardson, Murray
- Abstract:
- Random Forest (RF) is a widely used algorithm for classification of remotely sensed data. Through a case study in peatland classification using LiDAR derivatives, we present an analysis of the effects of input data characteristics on RF classifications (including RF out-of-bag error, independent classification accuracy and class proportion error). Training data selection and specific input variables (i.e., image channels) have a large impact on the overall accuracy of the image classification. High-dimension datasets should be reduced so that only uncorrelated important variables are used in classifications. Despite the fact that RF is an ensemble approach, independent error assessments should be used to evaluate RF results, and iterative classifications are recommended to assess the stability of predicted classes. Results are also shown to be highly sensitive to the size of the training data set. In addition to being as large as possible, the training data sets used in RF classification should also be (a) randomly distributed or created in a manner that allows for the class proportions of the training data to be representative of actual class proportions in the landscape; and (b) should have minimal spatial autocorrelation to improve classification results and to mitigate inflated estimates of RF out-of-bag classification accuracy.
- Date Created:
- 2016-05-17
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- Resource Type:
- Article
- Creator:
- Fitzgerald, Saira
- Abstract:
- This article presents the results of the first phase of a research project on perceptions of the International Baccalaureate Diploma Program (IBDP) in Canadian universities. Establishing explicit university recognition policies for IBDP students has been an ongoing task for the International Baccalaureate Organization (IBO), which conducted two studies on university perceptions of the IBDP in the UK (2003) and Australia/New Zealand (2007). The present study replicates these studies in the Canadian context, to discover how admissions officers in Ontario universities perceive the IBDP in relation to other curricula. Preliminary results reveal a high degree of uniformity in responses, consistent with the previous studies. The IBO is indicated as being the primary source of information, suggesting that it plays an important part in forming perceptions of the IBDP.
- Date Created:
- 2016-05-17
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- Resource Type:
- Article
- Creator:
- Smith, Catherine A., Hayley, Shawn, Smith, Jeffrey, and Farmer, Kyle
- Abstract:
- Parkinson’s disease (PD) is a progressive neurodegenerative disease affecting the nigrostriatal pathway, where patients do not manifest motor symptoms until >50% of neurons are lost. Thus, it is of great importance to determine early neuronal changes that may contribute to disease progression. Recent attention has focused on lipids and their role in pro- and anti-apoptotic processes. However, information regarding the lipid alterations in animal models of PD is lacking. In this study, we utilized high performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) and novel HPLC solvent methodology to profile phosphatidylcholines and sphingolipids within the substantia nigra. The ipsilateral substantia nigra pars compacta was collected from rats 21 days after an infusion of 6-hydroxydopamine (6-OHDA), or vehicle into the anterior dorsal striatum. We identified 115 lipid species from their mass/charge ratio using the LMAPS Lipid MS Predict Database. Of these, 19 lipid species (from phosphatidylcholine and lysophosphotidylcholine lipid classes) were significantly altered by 6-OHDA, with most being down-regulated. The two lipid species that were up-regulated were LPC (16:0) and LPC (18:1), which are important for neuroinflammatory signalling. These findings provide a first step in the characterization of lipid changes in early stages of PD-like pathology and could provide novel targets for early interventions in PD.
- Date Created:
- 2016-05-17
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- Resource Type:
- Article
- Creator:
- Capaldi, Colin A., Dopko, Raelyne L., and Zelenski, John M.
- Abstract:
- Research suggests that contact with nature can be beneficial, for example leading to improvements in mood, cognition, and health. A distinct but related idea is the personality construct of subjective nature connectedness, a stable individual difference in cognitive, affective, and experiential connection with the natural environment. Subjective nature connectedness is a strong predictor of pro-environmental attitudes and behaviors that may also be positively associated with subjective well-being. This meta-analysis was conducted to examine the relationship between nature connectedness and happiness. Based on 30 samples (n = 8523), a fixed-effect meta-analysis found a small but significant effect size (r = 0.19). Those who are more connected to nature tended to experience more positive affect, vitality, and life satisfaction compared to those less connected to nature. Publication status, year, average age, and percentage of females in the sample were not significant moderators. Vitality had the strongest relationship with nature connectedness (r = 0.24), followed by positive affect (r = 0.22) and life satisfaction (r = 0.17). In terms of specific nature connectedness measures, associations were the strongest between happiness and inclusion of nature in self (r = 0.27), compared to nature relatedness (r = 0.18) and connectedness to nature (r = 0.18). This research highlights the importance of considering personality when examining the psychological benefits of nature. The results suggest that closer human-nature relationships do not have to come at the expense of happiness. Rather, this meta-analysis shows that being connected to nature and feeling happy are, in fact, connected.
- Date Created:
- 2016-05-17
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- Resource Type:
- Article
- Creator:
- Zhou, Wenjun, Barry, Seán T., Mandia, David J., and Albert, Jacques
- Abstract:
- The optical properties of an ultrathin discontinuous gold film in different dielectric surroundings are investigated experimentally by measuring the polarization-dependent wavelength shifts and amplitudes of the cladding mode resonances of a tilted fiber Bragg grating. The gold film was prepared by electron-beam evaporation and had an average thickness of 5.5 nm ( ± 1 nm). Scanning electron imaging was used to determine that the film is actually formed of individual particles with average lateral dimensions of 28 nm ( ± 8 nm). The complex refractive indices of the equivalent uniform film in air at a wavelength of 1570 nm were calculated from the measurements to be 4.84−i0.74 and 3.97−i0.85 for TM and TE polarizations respectively (compared to the value for bulk gold: 0.54-i10.9). Additionally, changes in the birefringence and dichroism of the films were measured as a function of the surrounding medium, in air, water and a saturated NaCl (salt) solution. These results show that the film has stronger dielectric behavior for TM light than for TE, a trend that increases with increasing surrounding index. Finally, the experimental results are compared to predictions from two widely used effective medium approximations, the generalized Maxwell-Garnett and Bruggeman theories for gold particles in a surrounding matrix. It is found that both of these methods fail to predict the observed behavior for the film considered.
- Date Created:
- 2015-05-21
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- Resource Type:
- Article
- Creator:
- Grammatikos, Alex
- Date Created:
- 2015-05-21
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- Resource Type:
- Article
- Creator:
- Gorelick, Root, Hassal, Christopher, Fraser, Danielle, and Rybczynski, Natalia
- Abstract:
- Spatial diversity patterns are thought to be driven by climate-mediated processes. However, temporal patterns of community composition remain poorly studied. We provide two complementary analyses of North American mammal diversity, using (i) a paleontological dataset (2077 localities with 2493 taxon occurrences) spanning 21 discrete subdivisions of the Cenozoic based on North American Land Mammal Ages (36 Ma – present), and (ii) climate space model predictions for 744 extant mammals under eight scenarios of future climate change. Spatial variation in fossil mammal community structure (b diversity) is highest at intermediate values of continental mean annual precipitation (MAP) estimated from paleosols (,450 mm/year) and declines under both wetter and drier conditions, reflecting diversity patterns of modern mammals. Latitudinal gradients in community change (latitudinal turnover gradients, aka LTGs) increase in strength through the Cenozoic, but also show a cyclical pattern that is significantly explained by MAP. In general, LTGs are weakest when continental MAP is highest, similar to modern tropical ecosystems in which latitudinal diversity gradients are weak or undetectable. Projections under modeled climate change show no substantial change in b diversity or LTG strength for North American mammals. Our results suggest that similar climate-mediated mechanisms might drive spatial and temporal patterns of community composition in both fossil and extant mammals. We also provide empirical evidence that the ecological processes on which climate space models are based are insufficient for accurately forecasting long-term mammalian response to anthropogenic climate change and inclusion of historical parameters may be essential.
- Date Created:
- 2015-05-21