The goals of this study were to use Geographic Information Systems (GIS) and remote sensing technologies to gain a better understanding of habitat requirements of a population of ocelots in south Texas, and then apply this knowledge to form a predictive model to locate areas of suitable habitat in Willacy and Cameron counties, Texas. Satellite imagery from August 1991 and August 2000 were classified into four land cover types: closed canopy, open canopy, water, and urban/barren. These classified images were converted into digital thematic maps for use in resource utilization studies and modeling. Location estimates (762 from 1991 and 406 from 2000) were entered into a GIS in order to extract information about home range and resource selection. Each animal's home range was calculated using both Minimum Convex Polygon (MCP) and Kernel home range estimators (95% and 50%). Habitat parameters of interest were: soil, land cover, human density, road density, and distance to closest road, city and water body. Ocelots were found to prefer closed canopy and avoid open canopy land cover types. Ocelots preferred soils known to support thorn scrub, an indication of the importance of this habitat. Landscape metrics associated with habitat used by ocelots were determined through the use of Patch Analyst, an extension for ArcView 3.2. Contrary to expectations, ocelots utilized areas with greater fragmentation than random areas available for use. However, this use of highly fragmented areas was an indication of the degree of fragmentation of suitable habitat in the area. Further investigation of patch size selection indicated that ocelots used large sized patches disproportionately to availability, indicating a preference for larger patches. A model was created using the resource selection and habitat preference GIS database from 1991. This model was used to identify areas of “optimal”, ”sub-optimal”, and “unsuitable” habitat for ocelots in 2000. This resultant map was compared to known locations of ocelots in 2000. Ocelots were found to prefer optimal habitat and avoid unsuitable habitat, an indication that the model created was valid.

<p> Inclement challenges of a changing climate and humanity's desire to explore extraterrestrial environments both necessitate efficient methods to obtain freshwater. To accommodate next generation water technology, there is a need for understanding and defining the energy efficiency for unconventional water sources over a broad range of environments. Exergy analysis provides a common description for efficiency that may be used to evaluate technologies and water sources for energy feasibility. This work uses robust thermodynamic theory coupled with atmospheric and planetary data to define water capture efficiency, explore its variation across climate conditions, and identify technological niches and development needs.  </p> <p><br></p> <p> We find that desalinating saline liquid brines, even when highly saline, could be the most energetically favorable option for obtaining water outside of Earth. The energy required to access water vapor may be four to ten times higher than accessing ice deposits, however it offers the capacity for decentralized systems. Considering atmospheric water vapor harvesting on Earth, we find that the thermodynamic minimum is anywhere from 0x (RH≥ 100%) to upwards of 250x (RH<10\%) the minimum energy requirement of seawater desalination. Sorbents, modelled as metal organic frameworks (MOFs), have a particular niche in arid and semi-arid regions (20-30%). Membrane-systems are best at low relative humidity and the region of applicability is strongly affected by the vacuum pumping efficiency. Dew harvesting is best at higher humidity and fog harvesting is optimal when super-saturated conditions exist. Component (e.g., pump, chiller, etc.) inefficiencies are the largest barrier in increasing process-level efficiency and strongly impact the regions optimal technology deployment. The analysis elucidates a fundamental basis for comparing water systems energy efficiency for outer space applications and provides the first thermodynamics-based comparison of classes of atmospheric water harvesting technologies on Earth.</p>

No description available.

No description available.

<p><strong>Background and Objectives</strong>: Tools designed for systems analysis (SA) can link the different levels of healthcare by modeling the interacting, interrelated and interdependent components. The objective of this thesis was to investigate the use of discrete event simulation (DES) to help inform decision making.</p> <p><strong>Methods</strong>:</p> <p>Project 1: A new method is developed in which physicians and their delegates are modeled using DES as interacting pseudo-agents when simulating a hospital emergency department (ED).</p> <p>Project 2: Using a SA approach, we examined the referral patterns, healthcare utilization, time intervals and patient flow to identify rate limiting steps that may lead to delayed surgical candidacy and epilepsy surgery at the Hospital for Sick Children (SickKids) in Toronto, Ontario.</p> <p>Project 3: A DES model was developed of the surgical evaluation and surgery process and its associated constraints at SickKids to inform decision making at both the institutional and provincial levels. Once validated, the model was used to evaluate the effect of alternative resource capacities on waiting times.</p> <p><strong>Results:</strong></p> <p>Project 1: Neglecting the interaction between physician and delegates in the ED could result in misleading conclusions with respect to physician utilization and waiting times.</p> <p>Project 2: We found that only 5.7% of the eligible population was referred annually for surgical evaluation and that children waited on average 1-2 years for surgery. Through mapping of patient flow and resource utilization we were able to identify multiple barriers to surgery.</p> <p>Project 3: The findings support the recommendations to the province by directing requested funds to identified resources that would decrease waiting times.</p> <p><strong>Conclusions: </strong>SA tools can be used to make decisions that are generalizable to all levels of healthcare. Adopting the use of these tools increases the uptake of evidence in decision making and provides useful and critical information to develop comprehensive policies for improved healthcare.</p> / Doctor of Philosophy (PhD)

With the rapid evolution in mobile telecommunications, there is a significant need for more accurate and efficient management of resources such as CPU, RAM, and bandwidth. This thesis utilizes customer usage data alongside machine learning algorithms to predict resource demands, enabling telecommunications service providers to optimize service quality and reduce unnecessary costs. This thesis investigates enhancing mobile network cost prediction and resource utilization by integrating customer behavior analysis using machine learning models. As a predictive model we employed various machine learning techniques, including Random Forest Regressor and Recurrent Neural Networks (LSTM and GRU), and can effectively predict resource needs based on user events. Among these models, the Random Forest Regressor performed the best. This model enhances operational efficiency by providing precise resource predictions within the dataset ranges. / Med den snabba utvecklingen inom mobiltelekommunikation finns det ett betydande behov av mer exakt och effektiv hantering av resurser som CPU, RAM och bandbred. Rapporten använder data om kundanvändning tillsammans med maskininlärningsalgoritmer för att förutsäga resursbehov, vilket möjliggör att telekommunikationsleverantörer kan optimera tjänstekvalitet och minska onödiga kostnader. Detta examensarbete undersöker hur förutsägelser av kostnader och resursanvändning i mobila nätverk kan förbättras genom att integrera analys av kundbeteende med maskininlärningsmodeller. Som en prediktiv modell använde vi olika maskininlärningstekniker, inklusive Random Forest Regressor och Recurrent Neural Networks (LSTM och GRU), effektivt kan förutsäga resursbehov baserat på användarhändelser. Bland dessa modeller presterade Random Forest Regressor bäst. Denna modell förbättrar den operativa effektiviteten genom att ge mer precisa resurs prediktion inom datamängdens intervaller.

Résumé : La douleur lombaire (DL) est l’une des conditions musculosquelettiques les plus fréquentes et coûteuses au Canada. La prévalence annuelle de DL aigüe varierait de 19 % à 57 %, et un patient sur quatre souffrirait de récurrence dans la même année. La présente étude vise donc à produire une analyse descriptive de l’épidémiologie de la DL récurrente à l’échelle de la population. Une nouvelle approche méthodologique est proposée afin d’optimiser l’identification de vrais cas incidents de DL récurrente à partir d’une analyse secondaire de données administratives. Puisque 10 % des patients ayant de la DL seraient responsables de 80 % des coûts qui y sont associés, nous avons également déterminé la tendance séculaire des coûts d’interventions médicales des patients récurrents incidents entre 2003 et 2008. En utilisant le fichier des services médicaux rémunérés à l’acte de la Régie de l’assurance maladie du Québec, des cohortes prévalentes ont été construites à partir de 401 264 dossiers de patients ayant consulté au moins trois fois pour de la DL entre 1999 et 2008. Onze ans d’historique médical des 81 329 patients de la cohorte de 2007 ont ensuite été analysés afin d’exclure les patients ayant eu des consultations antérieures de DL. Une valeur prédictive positive et un coefficient de Kappa élevés ont permis d’identifier une clairance optimale pour récupérer les cas véritablement incidents. Les coûts de consultations ont ensuite été calculés pour tous les patients incidents de 2003 à 2007 à partir des manuels de facturation. Nous avons observé une prévalence annuelle de la DL récurrente de 1,64 % en 2000 chez les hommes diminuant à 1,33 % en 2007. Cette baisse a majoritairement eu lieu dans le groupe d’âge des 35-59 ans. Les femmes âgées (> 65 ans) étaient 1,4 fois plus à risque de consulter un médecin de manière récurrente que les hommes du même âge. L’incidence annuelle de la DL en 2007 était de 242 par 100 000 personnes. Les hommes de 18 à 34 ans étaient 1,2 fois plus à risque que les femmes de développer un premier épisode récurrent et les personnes âgées 1,9 fois plus à risque que les jeunes. L’incidence annuelle a diminué de 12 % entre 2003 et 2007 pendant que les coûts totaux augmentaient de 1,4 %. La médiane des coûts était la plus élevée chez les femmes âgées et tendait à augmenter dans le temps. Ces analyses secondaires suggèrent de s’intéresser particulièrement à la DL chez les personnes très âgées, et de déterminer si la baisse de fréquence de consultations récurrentes observée dans le temps est liée à une meilleure gestion de la DL ou à un problème d’accessibilité. Les coûts devraient faire l’objet d’un suivi continu pour limiter les hausses. // Abstract : Low back pain (LBP) is one of the most frequent and costly musculoskeletal health conditions in Canada. Annual prevalence was found to vary between 19 % and 57 % and likely one out of four patients experience a LBP recurrence within one year. The body of knowledge on the prevalence of recurrent LBP is still limited. This study sought to present a descriptive analysis on the epidemiology of recurrent LBP in a medical population. A new methodology is also proposed to identify true cases of incident recurrent LBP. Since 10 % of LBP patients have been reported to generate 80 % of the costs, we will sought to determine the secular trend of medical costs for the incident cohorts of 2003 to 2008. Using the Canadian province of Quebec medical administrative physicians’ claims database, 401 264 prevalent claims-based recurrent LBP patients were identified between 1999 to 2008 for having consulted at least three times for LBP in a period of 365 days. The medical history of 81 329 prevalent patients in 2007 was screened for a retrospective period of 11 years. High positive predictive values and Kappa statistics were used to determine the optimal clearance period for capturing true incidence cases among patients with no prior encounters for LBP. Physicians’ claims manuals were then used to apply a price for every intervention provided to LBP incident patients in their index year and follow-up years. We observed a decrease from 1.64 % to 1.33 % in the LBP annual prevalence between 2000 and 2007 for men. This decrease was mostly observed between 35 and 59 years of age. Older women (≥ 65 years) were 1.4 times more at risk to consult a physician for LBP in a recurrent manner than older men. The annual incidence in 2007 of adult claims-based recurrent LBP was 242 per 100 000 persons. Males of 18 to 34 years of age were found 1.2 times more at risk than their counterparts. Altogether, elderlies were 1.9 times more at risk than young adults to consult in a recurrent manner for LBP. The annual incidence decreased by 12 % between 2003 and 2007, while the direct costs increase by 1.4 %. The median cost for consultations was highest for elder women and increasing in time. These secondary analyses emphasize the importance to keep the watch on the elders in regards to LBP, and to determine if the timely decrease in morbidity is related to improvements in LBP management or to a medical accessibility issue. Also, costs will need to be surveyed on a regular basis to limit the impact of future increases.

Funding of services to residents in publicly funded long-term care (LTC) facilities has historically rested upon a list of physical needs. However, more than 60% of residents in nursing homes have dementia; a condition in which physical needs are only a part of the overall clinical picture. Since past funding formulas focused primarily on the physical characteristics of residents, the Ontario government has adopted the RUG (Resource Utilization Groups)-III (34 Group) for use in LTC facilities which follows the adoption of the Minimum Data Set (MDS) 2.0 assessment instrument. Some still question whether the newer formula adequately reflects the care needs of residents with dementia despite its validation in many countries. The purpose of this study was to determine the comprehensiveness of the RUG-III (34 Group) in addressing the needs of residents with dementia living in LTC. First, a critical systematic review of the literature was conducted to determine the needs of residents with dementia. Numerous electronic databases were searched for articles published between January 2000 and September 2010, and later cross-referenced. Second, needs identified from the literature were matched to the items of the RUG-III which are selected variables of the MDS 2.0. Third, the priority of the items in the RUG-III was analysed in accordance with the importance of the identified needs. The documented needs were taken from 68 studies and classified into 19 main categories. The needs most supported by the literature were the management of behavioural problems, social needs, the need for daily individualized activities/care and emotional needs/personhood. Among the needs identified, activities of daily living (ADLs), cognitive needs and general overall physical health met the most RUG-III items. These needs were found to be well represented within the system. Other needs of importance such as social needs are not thoroughly considered in the grouping methodology though matched to MDS variables. The fact that these needs are not well addressed in the RUG-III poses concerns. Future research is needed to validate the significance of these needs. Considerations should be made as to the adequacy of the funding system and the allocation of funding.

Funding of services to residents in publicly funded long-term care (LTC) facilities has historically rested upon a list of physical needs. However, more than 60% of residents in nursing homes have dementia; a condition in which physical needs are only a part of the overall clinical picture. Since past funding formulas focused primarily on the physical characteristics of residents, the Ontario government has adopted the RUG (Resource Utilization Groups)-III (34 Group) for use in LTC facilities which follows the adoption of the Minimum Data Set (MDS) 2.0 assessment instrument. Some still question whether the newer formula adequately reflects the care needs of residents with dementia despite its validation in many countries. The purpose of this study was to determine the comprehensiveness of the RUG-III (34 Group) in addressing the needs of residents with dementia living in LTC. First, a critical systematic review of the literature was conducted to determine the needs of residents with dementia. Numerous electronic databases were searched for articles published between January 2000 and September 2010, and later cross-referenced. Second, needs identified from the literature were matched to the items of the RUG-III which are selected variables of the MDS 2.0. Third, the priority of the items in the RUG-III was analysed in accordance with the importance of the identified needs. The documented needs were taken from 68 studies and classified into 19 main categories. The needs most supported by the literature were the management of behavioural problems, social needs, the need for daily individualized activities/care and emotional needs/personhood. Among the needs identified, activities of daily living (ADLs), cognitive needs and general overall physical health met the most RUG-III items. These needs were found to be well represented within the system. Other needs of importance such as social needs are not thoroughly considered in the grouping methodology though matched to MDS variables. The fact that these needs are not well addressed in the RUG-III poses concerns. Future research is needed to validate the significance of these needs. Considerations should be made as to the adequacy of the funding system and the allocation of funding.

R??sum?? : La douleur lombaire (DL) est l???une des conditions musculosquelettiques les plus fr??quentes et co??teuses au Canada. La pr??valence annuelle de DL aig??e varierait de 19 % ?? 57 %, et un patient sur quatre souffrirait de r??currence dans la m??me ann??e. La pr??sente ??tude vise donc ?? produire une analyse descriptive de l?????pid??miologie de la DL r??currente ?? l?????chelle de la population. Une nouvelle approche m??thodologique est propos??e afin d???optimiser l???identification de vrais cas incidents de DL r??currente ?? partir d???une analyse secondaire de donn??es administratives. Puisque 10 % des patients ayant de la DL seraient responsables de 80 % des co??ts qui y sont associ??s, nous avons ??galement d??termin?? la tendance s??culaire des co??ts d???interventions m??dicales des patients r??currents incidents entre 2003 et 2008. En utilisant le fichier des services m??dicaux r??mun??r??s ?? l???acte de la R??gie de l???assurance maladie du Qu??bec, des cohortes pr??valentes ont ??t?? construites ?? partir de 401 264 dossiers de patients ayant consult?? au moins trois fois pour de la DL entre 1999 et 2008. Onze ans d???historique m??dical des 81 329 patients de la cohorte de 2007 ont ensuite ??t?? analys??s afin d???exclure les patients ayant eu des consultations ant??rieures de DL. Une valeur pr??dictive positive et un coefficient de Kappa ??lev??s ont permis d???identifier une clairance optimale pour r??cup??rer les cas v??ritablement incidents. Les co??ts de consultations ont ensuite ??t?? calcul??s pour tous les patients incidents de 2003 ?? 2007 ?? partir des manuels de facturation. Nous avons observ?? une pr??valence annuelle de la DL r??currente de 1,64 % en 2000 chez les hommes diminuant ?? 1,33 % en 2007. Cette baisse a majoritairement eu lieu dans le groupe d?????ge des 35-59 ans. Les femmes ??g??es (> 65 ans) ??taient 1,4 fois plus ?? risque de consulter un m??decin de mani??re r??currente que les hommes du m??me ??ge. L???incidence annuelle de la DL en 2007 ??tait de 242 par 100 000 personnes. Les hommes de 18 ?? 34 ans ??taient 1,2 fois plus ?? risque que les femmes de d??velopper un premier ??pisode r??current et les personnes ??g??es 1,9 fois plus ?? risque que les jeunes. L???incidence annuelle a diminu?? de 12 % entre 2003 et 2007 pendant que les co??ts totaux augmentaient de 1,4 %. La m??diane des co??ts ??tait la plus ??lev??e chez les femmes ??g??es et tendait ?? augmenter dans le temps. Ces analyses secondaires sugg??rent de s???int??resser particuli??rement ?? la DL chez les personnes tr??s ??g??es, et de d??terminer si la baisse de fr??quence de consultations r??currentes observ??e dans le temps est li??e ?? une meilleure gestion de la DL ou ?? un probl??me d???accessibilit??. Les co??ts devraient faire l???objet d???un suivi continu pour limiter les hausses. // Abstract : Low back pain (LBP) is one of the most frequent and costly musculoskeletal health conditions in Canada. Annual prevalence was found to vary between 19 % and 57 % and likely one out of four patients experience a LBP recurrence within one year. The body of knowledge on the prevalence of recurrent LBP is still limited. This study sought to present a descriptive analysis on the epidemiology of recurrent LBP in a medical population. A new methodology is also proposed to identify true cases of incident recurrent LBP. Since 10 % of LBP patients have been reported to generate 80 % of the costs, we will sought to determine the secular trend of medical costs for the incident cohorts of 2003 to 2008. Using the Canadian province of Quebec medical administrative physicians??? claims database, 401 264 prevalent claims-based recurrent LBP patients were identified between 1999 to 2008 for having consulted at least three times for LBP in a period of 365 days. The medical history of 81 329 prevalent patients in 2007 was screened for a retrospective period of 11 years. High positive predictive values and Kappa statistics were used to determine the optimal clearance period for capturing true incidence cases among patients with no prior encounters for LBP. Physicians??? claims manuals were then used to apply a price for every intervention provided to LBP incident patients in their index year and follow-up years. We observed a decrease from 1.64 % to 1.33 % in the LBP annual prevalence between 2000 and 2007 for men. This decrease was mostly observed between 35 and 59 years of age. Older women (??? 65 years) were 1.4 times more at risk to consult a physician for LBP in a recurrent manner than older men. The annual incidence in 2007 of adult claims-based recurrent LBP was 242 per 100 000 persons. Males of 18 to 34 years of age were found 1.2 times more at risk than their counterparts. Altogether, elderlies were 1.9 times more at risk than young adults to consult in a recurrent manner for LBP. The annual incidence decreased by 12 % between 2003 and 2007, while the direct costs increase by 1.4 %. The median cost for consultations was highest for elder women and increasing in time. These secondary analyses emphasize the importance to keep the watch on the elders in regards to LBP, and to determine if the timely decrease in morbidity is related to improvements in LBP management or to a medical accessibility issue. Also, costs will need to be surveyed on a regular basis to limit the impact of future increases.