305 research outputs found
Projections of hydrometeorological processes in Southern Ontario: Uncertainties due to internal variability of climate
No full textFlooding is a major concern for Canadian society as it is the costliest natural disaster type in Canada. Southern Ontario, which houses one-third of the Canadian population, is particularly affected by early spring floods following snowmelt. During the last three decades, there has been a shift in flooding events from March-April to earlier months due to earlier snowmelt coupled with extreme rain events. Hydrological models run with different scenarios of climate change suggest further enhancement of this shift in the future. These projections of streamflow are associated with a cascade of uncertainties due to the choice of Global Climate Models (GCM’s), climate change scenarios, downscaling methods or hydrological models. A large part of the uncertainty is also associated with internal variability of climate due to the chaotic nature of the climate system. Despite these uncertainties, little is known about the impact of atmospheric circulation on past streamflow in southern Ontario and how the internal variability of climate is expected to impact the overall uncertainties in the projections of the future hydrological processes.
In this thesis, the Precipitation Runoff Modelling System (PRMS), a semi-distributed conceptual hydrological model, was established in four watersheds in southern Ontario to assess the impact of atmospheric circulation on the modulation of streamflow and number of high flows. Recurrent meteorological patterns (Or Weather regimes), based on 500hPa geopotential height (Z500), have been first identified in Northeastern North America using the k-means algorithm. The occurrences of these weather regimes patterns were used to create a regime-normalized hypothetical temperature and precipitation dataset that have been used as input in PRMS. Then, to investigate the future evolution of the hydrological processes, PRMS was forced with temperature and precipitation from the 50-members Canadian Regional Climate Model Large Ensemble (CRCM5-LE), a dynamically downscaled version of CanESM2-LE. The 50-members were classified into different classes of similar change in average temperature, precipitation and streamflow to identify the corresponding large-scale patterns. The specific focus of this analysis was on winter high flows, with the identification of a heavy rain and warm index, that can help to explain the generation of winter high flows in southern Ontario. The future evolution of these hydrometeorological extreme events, calculated for each member of CRCM5-LE, was analyzed with respect to the corresponding k-means weather regimes calculated for each member of CanESM2-LE. Finally, the uncertainties in the projections of the hydrometeorological extremes from the 50-members ensemble were compared to other sources of uncertainties using an analysis of variance applied to 504 simulations in the Big creek watershed. The high flows were projected using seven sets of PRMS parameters, 11 CMIP5 climate models forced with 2 scenarios of climate change and the 50 members of CRCM5-LE.
The results, focusing on the winter season, showed that weather regimes High-Pressure (HP) and southerly winds (South) are associated with a higher average streamflow volume and high-flows frequency in the historical period. Regime HP is characterized by high geopotential height anomalies on top of the Great Lakes region together with higher temperature and precipitation amounts. Regime South is characterized by high Z500 anomalies in the Atlantic east coast and is associated with stronger southerly winds and higher precipitation amount in southern Ontario. The temporal increase in HP in the past contributed more than 40% of the increase in average streamflow in winter. In the future, all 50 members of CRCM5-LE ensemble produce an increase in January-February streamflow. 14% of the ensemble depict a larger streamflow increase due to increase in Z500 anomalies in the east coast. This pattern, well defined by the regimes South, is expected to become a major contributor in the generation of hydrometeorological extreme events in Southern Ontario in the future. Regime HP is expected to contribute less to the high-flows due to the disappearance of snow. Overall, the contribution of internal variability of climate to high flows will be stable through the 21st century, primarily due to an increase in rainfall as generators of high flow events. The results suggest that the regional representation of rainfall in the GCMs-RCMs chains will be a critical area to improve with great societal implications for floods.DissertationDoctor of Science (PhD
Donut-Shaped mmWave Printed Antenna Array for 5G Technology
No full textThis article presents compact and novel shape ring slotted antenna array operating at mmWave band on central frequency of 28 GHz. The proposed structure designed at 0.256 mm thin Roggers 5880 is composed of a ring shape patch with a square slot etched at the top mid-section of partial ground plane. Through optimizing the ring and square slot parameters high bandwidth of 8 GHz is achieved ranging from 26 to 32 GHz with simulated gain of 3.95 dBi and total efficiency of 96% for single element. The proposed structure is further transformed in a 4 element linear array manner. With compact dimensions of 20 mm × 22 mm for array, the proposed antenna delivers high simulated gain of 10.7 dBi and is designed in such a way that it exhibits dual beam response over the entire band of interest and simulated results well agree with fabricated prototype measurements
EVALUATING THE IMPACTS OF EXTREME WEATHER EVENTS ON THE INFRASTRUCTURE DEVELOPMENT OR CONSTRUCTION INDUSTRY IN ONTARIO
No full textIn Canada, construction companies are facing disruptions to their operations due to bad or extreme weather conditions such as thunderstorms, heavy precipitation, flooding, heatwaves and snowstorms, which cause project delays, loss of productivity and increased financial costs. This sector is prone to more disruptions due to increase in the frequency, duration and intensity of extreme weather events due to future climate change. This study examined the impacts of extreme weather events on infrastructure development companies and investigated their current practices and actions to alleviate these impacts. A survey questionnaire was developed and administrated to owners, managers, engineers, supervisors and planners of construction companies. Apart from descriptive evaluations, the survey responses were quantitatively analyzed to determine the impact of bad weather conditions on the construction companies. The findings of this study suggested that most construction companies’ operations were delayed due to bad or extreme weather events. However, construction industry is not adopting proactive measures to avoid or minimize these impacts. The main environmental factors impacting construction companies, included flooding, high winds or thunderstorms, warm/cold temperatures, heatwaves and snow/ice storms. These bad weather impacts were more significant for non-government construction companies as compared to those working in the government sector. Indirect impacts of bad weather included disruptions to their supply chain networks and changes in customer behaviors; however, these impacts were minor compared to direct environmental impacts. The study found that both government and non-government sector construction companies granted accommodations to the workers during bad weather conditions; however, government sector companies were more accommodating as compared to non-government companies.
The study results also provided insight into the financial impacts of extreme weather events on construction companies. Weighted average losses for government sector companies were 8,155 per day for non-government companies. This suggested that non-government construction companies may experience serious financial consequences due to bad or extreme weather events. Study results further showed that there were no adequate guidelines, protocols or standards available to construction companies to adapt their operations and planning for extreme weather events. The study also highlighted the lack of adequate insurance products available for the construction sector to deal with bad weather. There was little tendency shown by the construction companies to use new technologies to deal with bad weather conditions. Therefore, there is an urgent need to develop guidelines, protocols or standards for construction companies by involving all levels of the government and relevant private sector organizations. This study helps to determine the nature and scale of extreme weather impacts on construction industry and explores what strategies may be developed to alleviate these impacts and risks. Such knowledge will help companies better plan and manage their operations and effectively use their human resources. It will help in timely delivery of services and savings in costs by the infrastructure development companies, which are a major contributor to the Canadian economy.ThesisMaster of Science (MSc
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Spatial aggregation of vegetation parameters in a coupled land surface-atmosphere model
No full textThe aggregation of heterogeneous land surface cover parameters to calculate effective area-average energy fluxes at microscale using a realistic coupled land surfaceatmosphere model are been investigated in this study. The Biosphere-Atmosphere Transfer Scheme (BATS) was merged with a two dimensional atmospheric boundary layer simulation model (ABLE) to develop a coupled model, BAT-ABLE. Observed land surface and atmospheric forcing data from the FIFE site in Kansas were used to initialize and run the time series of this model. The initial model states were obtained from seasonal runs of a stand-alone version of BATS using observed data. The horizontal model domain was set to 2 km, while the size of each patch was 1 km. The height of the first model grid level above the ground was set to 2 m to match the screen height at the FIFE site. Simple aggregation rules were used to aggregate BATS parameters to obtain area-average energy fluxes. Four cover types (short grass, long grass, mixed crop and irrigated crop) with five different patch combinations were tested using July 7, August 15, and October 11, 1987 observed data. The aggregation scheme worked well in almost all cases for these different days and times (am, noon, pm). However the aggregation scheme failed in the particular cases of artificially wet soil patches set in a landscape of dry soil. However, analysis of fluxes in this situation showed that this failure is not due to a difference in efficiency of atmospheric advection in this case, rather it is due to a real net change in the area-average turbulent fluxes returned to the atmosphere.hydrology collectio
Efficient Remote Gas Inspection with an Autonomous Mobile Robot
No full textHuman-caused greenhouse gas emissions are one of the major sources of global warming, which is threatening to reach a tipping point. Inspection systems that can provide direct information about critical factors causing global warming, such as systems for gas detection and location of gas sources, are urgently needed to analyze the fugitive emissions and take necessary actions. This thesis presents an autonomous robotic system capable of performing efficient exploration by selecting informative sampling positions for gas detection and gas distribution mapping – the Autonomous Remote Methane Explorer (ARMEx). In the design choice of ARMEx, a ground robot carries a spectroscopybased remote gas sensor, such as a Remote Methane Leak Detector (RMLD), that collects integral gas measurements along up to 30 m long optical-beams. The sensor is actuated to sample a large area inside an adjustable field of view, and with the mobility of the robot, adaptive sampling for high spatial resolution in the areas of interest is made possible to inspect large environments. In a typical gas sampling mission, the robot needs to localize itself and plan a traveling path to visit different locations in the area, which is a largely solved problem. However, the state-of-the-art prior to this thesis fell short of providing the capability to select informative sampling positions autonomously. This thesis introduces efficient measurement strategies to bring autonomy to mobile remote gas sensing. The strategies are based on sensor planning algorithms that minimize the number of measurements and distance traveled while optimizing the inspection criteria: full sensing coverage of the area for gas detection, and suitably overlapping sensing coverage of different viewpoints around areas of interest for gas distribution mapping. A prototype implementation of ARMEx was deployed in a large, real-world environment where inspection missions performed by the autonomous system were compared with runs teleoperated by human experts. In six experimental trials, the autonomous system created better gas maps, located more gas sources correctly, and provided better sensing coverage with fewer sensing positions than human experts
Analysing the Impact of Age, Body Condition, Scrotum Circumference Testicular Size and Hormone Levels in Pre-Pubertal Kundhi Buffalo Bull Calves
No full text: This study investigates and compares the physiological and behavioral characteristics of Kundhi buffalo bull calves focusing on the impact of age and size. Ten bull calves, aged between 14 to 18 months were selected and categorized into two groups: Group A: young (up to 14 months), with 210kg average body weight, and Group B: smaller (up to 18 months) with 305kg average body weight. The body weight of Kundhi buffalo calves linearly increased from the 1st to the 7th fortnight, with significant differences (p<0.05) observed between the two groups. The final body weight was higher in Group B (344.72 kg) when compared to Group A (262.04 kg). Similarly, scrotal circumference, girth, and length exhibited linear increases throughout the experiment with significant differences between the groups (p<0.05). Group B consistently showed larger scrotal circumferences (21.96 cm), girths (66.28 cm), and lengths (51.54 cm) compared to Group A (18.38 cm, 60.36 cm, and 47.44 cm, respectively). While testosterone and estradiol concentrations were non-significant (p>0.05) between the groups, they were higher in Group B (0.1504 ng/ml and 2.4724 pg/ml) than in Group A (0.1082 ng/ml and 2.2724 pg/ml). Behavioral observations, including nuzzling, sniffing, licking, bellowing, protrusion, and mounting, indicated higher scores in Group B. In both groups, mean nuzzling scores were (3.71 and 5.00), sniffing (0.28 and 1.28), licking (3.14 and 4.14), bellowing (0.85 and 2.14), protrusion (0.00 and 0.42), and mounting (0.00 and 1.28) in the "yes" category. These findings offer comprehensive insights into the physiological and behavioral differences influenced by age and size in Kundhi buffalo bull calves
Introduction of a new ZnMgAl-LTH@GCN nanosorbent in dispersive solid phase microextraction (dSP-μ-E) procedure for Pb(II) extraction
No full textGraphitic carbon nitride (GCN) and layer triple hydroxide (LTH) were used in the development of a dispersive solid phase microextraction (dSP-mu -E) method for preconcentration of Pb(II). The new nanocomposite sorbent ZnMgAl-LTH@GCN was synthesized using a hydrothermal co-precipitation process, and characterized using various methods such as FT-IR, FE-SEM, XRD, and EDX. Analytical parameters were optimized; including pH, adsorbent amount, elute concentration/volume/time, and sample volume, which were found to be respectively, 8 pH, 5 mg, 1 mol/L, 1.5 mL, 60 s, and 35 mL. The matrix effects were also determined. The results found to be the preconcentration factor 23.3, limit of quantification (LOQ) 1.88 mu g/L and limit of detection (LOD) 0.560 mu g/ L, respectively. A validation test was conducted using CRMs to ensure appropriate recovery outcomes. The %RSD was found to be in the range of 6.12-7.72 %, remaining below the 10 % threshold. Pb(II) level was determined in tea, tap and industrial waste water samples using the new dSP-mu -E method
SUSTAINABLE CONFLICT RESOLUTION: A CASE STUDY OF THE CONQUEST OF MAKKAH
No full textWhether East or West, the stature of Prophet Muhammad (upon whom be peace) is an acknowledged one because of his magnanimity which is not reserved for Muslims alone. The resolution of the conflicts in his life had not only been creative and constructive but also non-violent; achieving sustainable development goals simultaneously. This paper analyses the situation at the conquest of Makkah from the life of the last Prophet in Islam from the perspective of sustainable development. It explores the situation as early as the Treaty of Hudaibiya and examines it under the framework of the United Nation’s sustainable development goals and popular nongame theory of negotiation reviewed by P.H. Gulliver. It, therefore, concludes that the Seerah of the Prophet is a progressive tool to transpire the national and international agenda for sustainable development and can serve as an approach towards multi-disciplinary collaboration to attain peace in the region and ultimately in the whole wide world
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