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Long-range Communication Framework for Autonomous UAVsElchin, Mammadov 10 July 2013 (has links)
The communication range between a civilian Unmanned Aerial Vehicle (UAV) and a Ground Control Station (GCS) is affected by the government regulations that determine the use of frequency bands and constrain the amount of power in those frequencies. The application of multiple UAVs in search and rescue operations for example demands a reliable, long-range inter-UAV communication. The inter-UAV communication is the ability of UAVs to exchange data among themselves, thus forming a network in the air. This ability could be used to extend the range of communication by using a decentralized routing technique in the network. To provide this ability to a fleet of autonomous dirigible UAVs being developed at the University of Ottawa, a new communication framework was introduced and implemented. Providing a true mesh networking based on a novel routing protocol, the framework combines long-range radios at 900 MHz Industrial, Scientific and Medical (ISM) band with the software integrated into the electronics platform of each dirigible. With one radio module per dirigible the implemented software provides core functionalities to each UAV, such as exchanging flight control commands, telemetry data, and photos with any other UAV in a decentralized network or with the GCS. We made use of the advanced networking tools of the radio modules to build capabilities into the software for route tracing, traffic prioritization, and minimizing self-interference. Initial test results showed that without acknowledgements, packets can be received in the wrong order and cause errors in the transmission of photos. In addition, a transmission in a presence of a third broadcasting node slows down by 4-6 times. Based on these results our software was improved to control to flow of transmit data making the fragmentation, packetization, and reassembly of photos more reliable. Currently, using radios with half-wavelength dipole antennas we can achieve a one-hop communication range of up to 5 km with the radio frequency line-of-sight (RF LOS). This can be extended further by adding as many radio nodes as needed to act as intermediate hops.
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Essays on the Causal Relationship Between Short-Term and Long-Term Interest RatesRahimi, Azadeh 30 May 2014 (has links)
This thesis is about the causal relationship between interest rates. In chapter 1, with the help of time-series econometrics and by applying linear Granger causality tests based on the Toda-Yamamoto approach, the linear causality directions between the federal funds rate and five different interest rates during the last seven business cycles in the U.S. are investigated. We also examine the linear Granger causality directions between the overnight rate and five other interest rates during the last three business cycles in Canada.
In chapter 2, the Diks and Panchenko Granger causality test is applied to explore the nonlinear causality effects between the short-term and long-term interest rates. By combining nonlinear causality effects with the linear ones which are found in the first chapter, it is seen that during the related periods in the U.S. and Canada, the most common Granger causality direction between short-term and long-term interest rates is a bidirectional one. Moreover, our findings show that during recent periods, the federal funds rate and overnight rate Granger cause other interest rates significantly.
In chapter 3, the rolling window strategy is employed to detect the linear and nonlinear Granger causality relationship between the federal funds rate and the 10-year government bond rate, during different time horizons, investigating whether these causalities change with the passing of time. Our findings show that during different time horizons, there is a significant two-way Granger causality relationship between these interest rates.
Although we have a different interpretation of the existence of bidirectional causation between short-term and long-term interest rates, this conclusion provides some support to some post-Keynesian structuralists viewpoints like Pollin (2008). However, Pollin's claim indicating that with the passing of time the significant causality effects of the federal funds rate to the market rates becomes insignificant is not supported by the current thesis findings because our results demonstrate that these causality effects have not been diminishing over the most recent business cycles.
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Understanding the quality of life of personal care home residents with Alzheimer's disease and related dementias: Family caregivers' perspectivesRona, Hazel 13 September 2010 (has links)
Manitoba’s population is aging. Trends in personal care home (PCH) use have also changed so that residents today have more cognitive impairments including Alzheimer’s disease and related dementias (ADRD). While quality of life (QoL) has emerged as an important PCH research outcome, this literature is relatively sparse for residents with versus without ADRD. This study was conducted to examine the QoL of PCH residents with ADRD, using a recently developed but as of yet untested framework by Kane and colleagues (1999, as cited in Frytak; Kane 2001, 2003). The specific aims of this study were to gather family caregivers’ perspectives on: (a) the meaning of the six domains that constitute Kane et al.’s ADRD-specific PCH-QoL framework; (b) domains they considered to be more important or lacking from this framework; and, (c) general PCH policies, practices, and activities that currently (or could better) facilitate positive QoL experiences for their loved ones.
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The impact of aggressive parental disciplinary strategies implemented in childhood on externalizing and internalizing problem behaviour in early adulthoodTaillieu, Tamara L. 18 January 2011 (has links)
Parental use of aggressive discipline, specifically corporal punishment (CP) and psychological aggression (PA), has been shown to increase the risk of problem behaviours in children and adolescents. A major gap in the research concerns our lack of understanding regarding how CP and PA contribute to adverse development in adulthood. Because these techniques do not occur in isolation, a number of protective factors were also considered. Both CP and PA were associated with lower levels of parental warmth/support and responsiveness, and more inconsistency in discipline; whereas high induction was associted with more frequent CP and PA. CP predicted later partner violence, and PA predicted anxiety and lower self-esteem in adulthood, even after the effects of positive parenting were considered. These findings suggest that not only do CP and PA tend to occur within environments that are less conducive to positive development, but also predict problematic outcomes in adulthood even after protective factors are considered.
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Nedlagda deponier i Västerbottens län : Regional åtgärdsplan och prioriteringslistaEk, Liselott January 2014 (has links)
Due to national environmental goals, 191 closed landfills were inventoried according to a national methodology for inventory of polluted areas. The inventory took place in thirteen of the municipalities in the region of Västerbotten during the summer of 2013. 159 of the landfills were classified to risk class 3 on a scale of 4. Landfills in this category consist of diverse nature, ranging from adequate coverage but poor placement, to insufficient coverage and visible leakage, but without urgent risk. The purpose of this report was to follow up on the inventory. It resulted in identifying and prioritizing the actions required and a general plan of action for the landfills in the region. The focus was mainly on landfills in class 3, but those in risk class 2 are also included. This report was based mostly on forms for the closed landfills and a survey aimed at regional administrations. The result showed that the most common actions required were clean up, coverage, investigation of leakage and information about the unsuitability of depositing waste, including yard waste, at a closed landfill. A status division of the landfills in class 3 was determined, where the landfills that required actions were assigned the statuses +, 0 or -. Criteria for + includes proximity to vulnerable nature, risk for contamination of drinking water, poor coverage, or visible leakage. The landfills in class 2 should be prioritized for further actions, and after that those in risk class 3 with the + status.
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Long-Term Health Outcome of Adolescent Mood Disorders : Focus on Bipolar DisorderPäären, Aivar January 2015 (has links)
There has recently been an intense debate about the increased rate of bipolar disorders (BPD) in children and adolescents observed in clinical settings. Thus, there is great interest in child and adolescent symptoms of hypomania and whether these symptoms subsequently will develop into BPD. More knowledge about early signs could give insight into the development of the disorder. There are also concerns that hypomanic symptoms in adolescence indicate excess risk of other health conditions. It has been reported that patients with mood disorders have a high consumption of prescription drugs in different ATC classes. The primary objective of this thesis was to better understand the mental health outcome of adolescents with hypomania spectrum symptoms and to identify early risk factors for adult bipolar disorder among adolescents with mood disorders. In order to widen the scope and investigate health outcome of mood disorder in general psychopharmacological outcomes were included. A community sample of adolescents (N=2 300) in the town of Uppsala, Sweden, was screened for depressive symptoms. Both participants with positive screening and matched controls (in total 631) were diagnostically interviewed. Ninety participants reported hypomania spectrum episodes, while another 197 fulfilled the criteria for major depressive disorder (MDD) without a history of a hypomania spectrum episode. A follow-up after 15 years included a blinded diagnostic interview, a self-assessment of personality disorders, and national register data on prescription drugs and health services use. Adolescent mood symptoms, non-mood disorders, and family characteristics were assessed. Univariate and multivariate analyses were used. The results indicate that the phenomenology of the hypomania spectrum episodes during childhood and adolescence per se does not predict adult bipolar disorder. However, having both affective symptoms during adolescence and a family history of bipolar disorder increases the risk of developing bipolar disorders in adulthood. Disruptive disorder in childhood or adolescence as well as family histories of BPD emerged as significant risk factors that differentiated between the future development of BPD and MDD. Adolescents with hypomania spectrum episodes and adolescents with MDD do not differ substantially in health outcomes in adulthood. Both groups are at increased risk for subsequent mental health problems, high consumption of prescription drugs, and high health care use, compared with the control group. The high rates of prescription drugs in many ATC classes found among the former depressed females seem to indicate a series of co-morbid somatic illnesses. Thus, it is important to identify and treat children and adolescents with mood disorders, and carefully follow the continuing course. Characteristics such as disruptive disorders and family history warrant particular attention.
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Anorectal Malformations : Long-term outcome and aspects of secondary treatmentDanielson, Johan January 2015 (has links)
Faecal incontinence (FI) is defined as the inability to control bowel movements. The causes of FI are many and diverse. One of the more uncommon reasons for FI is Anorectal Malformations (ARMs). An ARM is a congenital anomaly that affects somewhere between 1/2500 and 1/5000 live born babies. Many ARM patients have persistent FI. Several different procedures have been utilised to address this issue. This thesis aims to evaluate (1) the long-term outcome in adulthood of ARMs in relation to the modern Krickenbeck classification, and (2) scope for treating FI with transanal injection with dextranomer in non-animal stabilised hyaluronic acid (NASHA/Dx), in patients both with and without ARMs. All patients treated for ARMs in Uppsala up to 1993 were invited to participate in a questionnaire study of quality of life and function. The study included 136 patients and compared them with 136 age- and sex-matched controls. The Krickenbeck classification was found to predict functional outcome, and ARM patients had more problems with incontinence and obstipation, as well as inferior Quality of Life (QoL), compared with controls. Thirty-six patients with FI, owing to causes other than ARMs, were treated with transanal submucous injection of NASHA/Dx. The patients were monitored for two years after treatment. Significant reductions in both their incontinence score and the number of their incontinence episodes were achieved. A significant improvement in QoL was observed in patients who had at least a 75% reduction in incontinence episodes. No serious complications occurred. A prospective study of transanal injection of NASHA/Dx was conducted on seven patients with persistent FI after ARMs. After six months a significant reduction in the number of incontinence episodes was obtained. A significant improvement in QoL was also found. No serious complications occurred. In conclusion, adult patients with ARMs have inferior outcome of anorectal function and QoL compared with controls. NASHA/Dx is effective and appears to be safe in treating FI in general. This effect seems to be the same in selected patients with persistent FI after ARMs.
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Analysis and Applications of Heterogeneous Multiscale Methods for Multiscale Partial Differential EquationsArjmand, Doghonay January 2015 (has links)
This thesis centers on the development and analysis of numerical multiscale methods for multiscale problems arising in steady heat conduction, heat transfer and wave propagation in heterogeneous media. In a multiscale problem several scales interact with each other to form a system which has variations over a wide range of scales. A direct numerical simulation of such problems requires resolving the small scales over a computational domain, typically much larger than the microscopic scales. This demands a tremendous computational cost. We develop and analyse multiscale methods based on the heterogeneous multiscale methods (HMM) framework, which captures the macroscopic variations in the solution at a cost much lower than traditional numerical recipes. HMM assumes that there is a macro and a micro model which describes the problem. The micro model is accurate but computationally expensive to solve. The macro model is inexpensive but incomplete as it lacks certain parameter values. These are upscaled by solving the micro model locally in small parts of the domain. The accuracy of the method is then linked to how accurately this upscaling procedure captures the right macroscopic effects. In this thesis we analyse the upscaling error of existing multiscale methods and also propose a micro model which significantly reduces the upscaling error invarious settings. In papers I and IV we give an analysis of a finite difference HMM (FD-HMM) for approximating the effective solutions of multiscale wave equations over long time scales. In particular, we consider time scales T^ε = O(ε−k ), k =1, 2, where ε represents the size of the microstructures in the medium. In this setting, waves exhibit non-trivial behaviour which do not appear over short time scales. We use new analytical tools to prove that the FD-HMM accurately captures the long time effects. We first, in Paper I, consider T^ε =O(ε−2 ) and analyze the accuracy of FD-HMM in a one-dimensional periodicsetting. The core analytical ideas are quasi-polynomial solutions of periodic problems and local time averages of solutions of periodic wave equations.The analysis naturally reveals the role of consistency in HMM for high order approximation of effective quantities over long time scales. Next, in paperIV, we consider T^ε = O(ε−1 ) and use the tools in a multi-dimensional settingto analyze the accuracy of the FD-HMM in locally-periodic media where fast and slow variations are allowed at the same time. Moreover, in papers II and III we propose new multiscale methods which substantially improve the upscaling error in multiscale elliptic, parabolic and hyperbolic partial differential equations. In paper II we first propose a FD-HMM for solving elliptic homogenization problems. The strategy is to use the wave equation as the micro model even if the macro problem is of elliptic type. Next in paper III, we use this idea in a finite element HMM setting and generalize the approach to parabolic and hyperbolic problems. In a spatially fully discrete a priori error analysis we prove that the upscaling error can be made arbitrarily small for periodic media, even if we do not know the exact period of the oscillations in the media. / <p>QC 20150216</p> / Multiscale methods for wave propagation
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Physical Activity Levels & Correlates 2-6 Years Post-rehabilitation in Cardiac PatientsKhan, Shazareen N. 12 December 2011 (has links)
Many patients do not maintain physical activity (PA) post cardiac rehabilitation (CR),however few studies examine a large enough sample over the long-term. Thus, a retrospective cross-sectional study was carried out to examine PA and its correlates 2-6 years post CR; 584 graduates completed a mailed survey (mean+SD age: 69.8+9.8 years, BMI: 27+5.0 kg/m2, 80% male, 41.4+11.6 months since graduation, 36% response rate). PA was assessed using the Physical Activity Scale for the Elderly (PASE, mean+SD: 122.3+75.9). Seventy five percent of participants met Canadian PA guidelines. Greater PA was significantly associated with male sex, younger age, fear of falling, cholesterol control, self-controlled transportation, marital status, full-time work, rural location, higher VO2max, more comorbid conditions, greater perceived
health, PA enjoyment, quality of life (QOL), social support, income, and CR staff support. Age,PA enjoyment, QOL, work status, cholesterol control and CR staff were significant in a multivariate model (R2=0.22, F=18.7, p<0.001).
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Long-term Complications Associated with Implant-supported Complete Fixed Dental ProsthesisShokati, Babak 17 July 2013 (has links)
Rehabilitation of edentulous patients with Implant-supported Complete Fixed Dental Prosthesis (ICFDP) is a well-documented treatment option. This dissertation assessed the relation between the rate of biological/mechanical complications and the type of metal framework alloy, length of cantilever extension.
The results showed that long-term clinical outcomes of ICFDP were favorable. While 30% of patients experienced biological complications, 66.6% of the prostheses needed to be repaired during follow-up period. The risk of prosthesis failure and mechanical complications was significantly higher in silver-palladium frameworks as compared with palladium-silver or type IV gold alloys.
The length of cantilever was not correlated with the amount of marginal bone loss. The rate of marginal bone loss around anterior implants was higher than that of posterior implants associated with cantilever segments. The treatment improved the patients’ quality of life and 96% of patients would undergo the same treatment again if required.
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