Gastric banding as a weight loss surgery has increased in popularity in the United States since its approval by the Food and Drug Administration in 2001. Successful weight loss after weight loss surgery is most frequently defined as greater than 50 percent of excess weight loss (EWL). Systematic reviews show that the band is widely effective in achieving successful weight loss in most patients, however individual studies show more inconsistent outcomes. Although previous research supports gastric bypass surgery as having a positive effect on quality of life after gastric bypass, there is very little data to support this relationship in gastric banding patients. Weight loss outcomes after gastric banding surgery at Virginia Commonwealth Health System were less than 50 per cent EWL at one and two years. A retrospective, descriptive study sought to answer the following questions: 1) What is the relationship between physical activity, eating behaviors and hunger control on weight loss and quality of life after gastric banding surgery and 2) Does successful weight loss at one year predict successful weight loss at two years. The International Physical Activity Questionnaire Sort Form (IPAQ) was used to assess participation in physical activity. The Medical Outcomes Study Short Form (SF-36) was used to determine quality of life. Weight loss outcomes were 34.6 per cent at one year and 39.7 per cent at two years, which was less than the established success rate of greater than 50 per cent EWL, However, most patients lost some weight and demonstrated a significant improvement in most domains of health related quality of life. Participation in physical activity increased fro preoperatively to year one but decreased in year two. Although participation in physical activities overall decreased from year one to year two, there was a significant relationship between participation in greater than 150 minutes per week of moderate or vigorous physical activity and adequate weight loss (p =0.025) and participation in health enhancing physical activities and adequate weight loss (p < 0.05). There was no statistically significant relationship noted between any of these eating behaviors and the percentage of excess weight loss at one or two years. There was a significant relationship between degree of hunger reported by patients and successful weight loss at one year (p < 0.05). There is sufficient statistical evidence of a positive linear relationship between two- year weight loss and one- year weight loss (p < 0.05). That is, one-year weight loss is a significant predictor for two- year weight loss. Based on the results of this study, it is recommended that gastric banding patients participate in at least 150 minutes per week of moderate to vigorous physical activity. Additionally, clinicians should consider development of adjustment protocols that achieve early reduction of hunger in the banding patient.

Teleskophandtaget på en resväska är troligen det användaren är i kontakt med mest och kanske även det som berörs först vid val av resväska. Det gör att det har en viktig roll i att förmedla en uppfattning om resväskans kvalitet. Detta projekt har initierats av företaget Thule Sweden AB som arbetar med transportlösningar för personliga föremål, däribland exempelvis resväskor som är det affärsområde projektet tillhörde. Projektet syftar till att utveckla deras befintliga teleskophandtag till att erbjuda större valfrihet i höjdjustering. Thule kännetecknas av, och strävar efter, att ta fram funktionella och genomtänkta lösningar med hög kvalitet och säkerhet. De tror att utveckling av teleskophandtaget kan höja kvalitetsuppfattning av resväskan i stort. Projektet har genomförts som ett examensarbete för maskiningenjörsutbildningen på Mittuniversitetet i Östersund. I rapporten redovisas de delar av produktutvecklingsprocessen projektet innefattat och alla resultat från de olika metoder som använts. Processen delades in i de tre faserna: produktspecificering, konceptgenerering samt konceptutvärdering. Resultatet av projektet blev två konceptuella lösningar till låsmekanismer för steglös höjdjustering. Dessa anpassades för integrering i Thules befintliga teleskophandtag. Den ena av mekanismerna bygger på mekanisk låsning och den andra på friktionslåsning. Med anledning av att koncepten skiljer sig åt i teknik samt att Thule ansåg att båda hade intressanta egenskaper valdes båda till slutkoncept. Lösningarna presenteras både i form av digitala solidmodeller och 3Dprintade prototyper. De båda konceptuella lösningarna behöver utvärderas vidare bland annat genom att undersöka om det är möjligt att skapa ett tillräckligt högt motstånd med friktionslösningen samt om det är möjligt att minska vikten hos den mekaniska lösningen. Den viktigaste slutsatsen av projektet är att det bör vara fullt möjligt att utveckla ett steglöst teleskophandtag som passar Thules varumärkesmässiga profil och som faktiskt höjer kvalitetskänslan. / The telescope handle on a suitcase is probably what the user is in contact with most and perhaps also what is touched first when choosing a suitcase. This means that it has an important role to play in conveying a conception of the suitcase quality. This project has been initiated by the company Thule Sweden AB, which works with transport solutions for personal items, including, among other things suitcases that are the business area the project belonged to. The project aims to develop their existing telescopic handles to offer greater freedom of choice in height adjustment. Thule is characterized by, and strives for, to develop functional and well-thought-out solutions with high quality and safety. They believe that the development of the telescopic handle can increase the quality perception of the suitcase in general. The project has been carried out as a degree project for the mechanical engineering program at the Mid Sweden University in Östersund. In the report, the parts of the product development process are included in the project and all results from the various methods used. The process was divided into the three phases: product specification, concept generation and concept evaluation. The result of the project was two conceptual solutions for locking mechanisms for continuous height adjustment. These were adapted for integration in Thule's existing telescopic handles. One of the mechanisms is based on mechanical locking and the other on friction locking. Due to the fact that the concepts differ in technology and that Thule considered that both had interesting properties, both were chosen as final concepts. The solutions are presented both in the form of digital solid models and 3D-printed prototypes. The two conceptual solutions need to be further evaluated, among other things by examining whether it is possible to create a sufficiently high locking resistance with the friction solution and whether it is possible to reduce the weight of the mechanical solution. The most important conclusion of the project is that it should be possible to develop a continuous height adjustable telescopic handle that fits Thule's brand profile and which actually increases the feeling of quality. / <p>Betyg: 2019-08-15</p>

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Este trabalho aborda os efeitos de afundamentos de tensÃo em Acionamentos de Velocidade VariÃvel â AVVs para mÃquinas de corrente alternada, conversores estÃticos de dois estÃgios (retificador-inversor) amplamente utilizados no controle de velocidade e traÃÃo. O estudo tem como objetivo analisar o comportamento dos AVVs diante de afundamentos de tensÃo simÃtricos e assimÃtricos e tÃcnicas de aumento de suportabilidade para estes equipamentos, destacando-se o uso de conversores boost. SÃo apresentados resultados de simulaÃÃes computacionais e de ensaios laboratoriais de um conversor boost desenvolvido para aumentar a tolerÃncia de AVV a afundamentos de tensÃo. Nos ensaios de laboratÃrio foram levantadas as curvas de tolerÃncia do AVV para afundamentos de tensÃo dos tipos A, B e E e comparadas aos limites estabelecidos pela curva SEMI F47 0706 do instituto EPRI. O AVV mostrou-se sensÃvel aos afundamentos tipo A e E com imunidade de tensÃo remanescente de atà 0,7pu na barra CC do AVV. Foram ainda feitos ensaios experimentais com o conversor boost conectado ao AVV sob condiÃÃes de afundamentos de tensÃo severos dos tipos A e E. A anÃlise do conjunto AVV-MIT sob os demais tipos de afundamentos de tensÃo (B, C, D, F e G) foi feita por simulaÃÃo computacional usando um modelo previamente validado pela comparaÃÃo com os resultados experimentais. Os afundamentos dos tipos A, E, F e G, que podem provocar o desligamento do AVV, foram tambÃm analisados por simulaÃÃes computacionais com a conexÃo do conversor boost ao barramento CC do AVV. Para a avaliaÃÃo do comportamento do AVV com e sem o conversor boost foram obtidas as curvas de tensÃo do barramento CC, tensÃo de saÃda do AVV, tensÃo de entrada do conversor boost, e de correntes de entrada do AVV, do conversor boost e de saÃda da fonte. Conforme os resultados de simulaÃÃes e experimentais o conversor boost pode mitigar afundamentos do tipo A para atà 0,5pu e todos os outros tipos de afundamentos atà nÃveis de interrupÃÃo, isto Ã, 0pu. Comparados os resultados com as simulaÃÃes de outras soluÃÃes abordadas no trabalho, o conversor boost se mostrou como a melhor alternativa do ponto de vista tÃcnico. / This work investigates the effects of voltage sags on Adjustable Speed Drives â ASDs of AC machines, static converters of two stages (rectifier-inverter) widely used on speed and torque control. The goal is to analyse the behavior of the ASDs under symmetrical and asymmetrical voltage sags and the approaches to improve the ASD low voltage ride-through capability with emphasis to the boost converter technique. Computational simulations and experimental results of a boost converter designed to operate when the ASD is under voltage sags are presented. The tolerance curves of the ASD were obtained in laboratory for voltage sags types A, B and E and compared to the SEMI F47 0706 curve of the EPRI institute. The ASD was shown sensitive for voltage sags types A and E with immunity for remaining voltages up to 0.7pu on the DC link. Experimental tests were performed to evaluate the response of the boost converter operation when the ASD is under severe voltage sag conditions of types A and E. The set ASD-induction motor was modelled for the simulation tests and the model validation was performed by comparison with experimental results. The analysis of the ASD and the three-phase induction motor under voltage sags B, C, D, F e G were carried out by computational simulations. The voltage sag types A, E, F and G which can turn off the ASD were also analyzed by computational simulation with the boost converter connected to ASD DC bus. The curves of DC link voltage, the ASD output voltage, the boost input voltage and the input currents of the ASD, the boost converter and the source were plotted for evaluation of the ASD behavior with and without the boost converter. The simulation and experimental results have shown that the boost converter can mitigate voltage sags type A up to 0.5pu and all other types of voltage sags up to 0pu. The boost converter has proved a suitable solution to improve the ASD voltage sag ride through capability.

As power electronic based controllers and loads become more prevalent in power systems, there is a growing concern about how the harmonics generated by these controllers and loads affect the power quality of the system. One widely used power electronic based load is the Variable Frequency Drive (VFDs) used to vary the speed of an induction motor; whereas a common example of a power electronic based controller used in power systems is the Static VAR Compensator (SVC) for improving a system’s power factor. In this thesis, the harmonic content and overall performance of a system including both a VFD and a SVC will be studied and analyzed. Specifically, the cases of no compensation, static capacitor compensation, and power electronic based static VAR compensation are examined. A small-scale model of a system for study was constructed in lab. Several cases were then performed and tested to simulate a system which contained both fixed and power electronic based harmonic generating loads. The performance of each case was determined by total harmonic current and voltage distortions, true power factor, and RMS current levels at different points in the system.

Variable rate mortgages (VRMs) have been introduced into the mortgage market as a means of addressing the housing finance problems encountered over the past two decades. To learn more about the demand for VRMs, this study analyzes borrower choice behavior and its economic determinants. In order to estimate the probability of borrowers choosing VRMs rather than conventional fixed rate mortgages, discrete choice (logit) models are specified and validated for both cross-section and pooled time-series cross-section data samples. These samples contain mortgage application information for the years 1978 through 1981. They were drawn from the Loan Register Report of the California Department of Savings and Loan. The probability of choosing a VRM is estimated as a function of selected price components of the mortgage instrument, borrower characteristics, and economic expectations.

Bariatric surgery is an effective procedure type for morbidly obese patients when all else fails. Because obesity is a chronic disease, prolonged assessment and understanding of the credibility of procedure types and their effects on bariatric surgery outcomes are essential, yet current evidence shows decreasing utilization of one of the dominant procedure types. To better compare outcomes of procedure type, this research was designed to control for volume, hospital size, age, gender, season, month, year, and ethnicity. The goal of the study was to compare the outcomes of laparoscopic adjustable gastric banding (LAGB) and laparoscopic sleeve gastrectomy (LSG) bariatric surgery using the epidemiologic triad model. This study was a retrospective cross-sectional review of Nationwide Inpatient Sample (NIS) from 2009 to 2014. Univariate and multivariate logistic regression were conducted to analyze the data. This study was based on a secondary analysis previously collected from NIS data. A convenience sample of 73,086 patients who underwent bariatric surgery using ICD-9 diagnosis and procedure codes was used. Multiple logistic regression analysis indicated that LAGB (odds ratio [OR] =.043) and LSG (OR =.030) were positively associated with in-hospital mortality. Similarly, LAGB (OR =.041) and LSG (OR =.425) were positively correlated to length of stay (LOS). Finally, LAGB (OR = .461) and LSG (OR = .480) was positively related to reoperation. LAGB, when compared to LSG for LOS, had a substantial advantage over biliopancreatic diversion. The LOS findings may contribute to patients' value proposition, including cost reduction for third party insurance payers and for the community.

Dynamic memory allocators are a determining factor of an application's performanceand have the opportunity to improve a major performance bottleneck ontoday's computer hardware: data locality. To approach this problem, a memoryallocator must rst oer strategies that allow the locality problem to be addressed.However, while focusing on locality, an allocator must also not ignore the existing constraintsof allocation speed and fragmentation, which further complicate its design. Inorder for a locality improving technique to be successfully employed in today's largecode applications, its integration needs to be automatic, without user intervention.The alternative, manual integration, is not a tractable solution.In this dissertation we develop three novel memory allocators that explore dierentallocation strategies that enhance an application's locality. We conduct the rststudy that shows that allocation speed, fragmentation and locality improving goalsare antagonistic. We develop an automatic method that supplies allocation hintsfrom C++ STL containers to their allocators. This method allows applications tobenet from locality improving techniques at the cost of a simple re-compilation. Weconduct the rst study that quanties the eect of allocation hints on performance,and show that an allocator with high locality of reference can be as competitive asone using an application's spatial feedback.To further allow dynamic memory allocation to improve an application's performance,new and non-traditional strategies need be explored. We develop a generic software tool that allows users to examine unconventional strategies. The tool allowsusers not only to focus on allocation strategies rather than their implementation, butalso to compare and contrast various approaches.

Wireless sensor networks are made up of a large number of sensors deployed randomly in an ad-hoc manner in the area/target to be monitored. Due to their weight and size limitations, the energy conservation is the most critical issue. Energy saving in a wireless sensor network can be achieved by scheduling a subset of sensor nodes to activate and allowing others to go into low power sleep mode, or adjusting the transmission or sensing range of wireless sensor nodes. In this thesis, we focus on improving the lifetime of wireless sensor networks using both smart scheduling and adjusting sensing ranges. Firstly, we conduct a survey on existing works in literature and then we define the sensor network lifetime problem with range assignment. We then propose two completely localized and distributed scheduling algorithms with adjustable sensing range. These algorithms are the enhancement of distributed algorithms for fixed sensing range proposed in the literature. The simulation results show that there is almost 20 percent improvement of network lifetime when compare with the previous approaches.

In this thesis, we explore the topic of designing an architecture and processing algorithms for a multi-agent system, where agents need to address potential unexpected events in the environment, operating under soft real-time constraints. We first develop a classification of unexpected events into Opportunities, Barriers and Potential Causes of Failure, and outline the interaction required to support the allocation of tasks for these events. We then propose a hybrid architecture to provide for agent autonomy in the system, employing a central coordinating agent. Certain agents in the community operate autonomously, while others remain under the control of the coordinating agent. The coordinator is able to determine which agents should form teams to address unexpected events in a timely manner, and to oversee those agents as they perform their tasks. The proposed architecture avoids the overhead of negotiation amongst agent teams for the assignment of tasks, a benefit when operating under limited time and resource constraints. It also avoids the bottleneck of having one coordinating agent making all decisions before work can proceed in the community, by allowing some agents to work independently. We illustrate the potential usefulness of the framework by describing an implementation of a simulator loosely based on that used for the RoboCup Rescue Simulation League contest. The implementation provides a set of simulated computers, each running a simple soft real-time operating system. On top of this basic simulation we implement the model described above and test it against two different search-and-rescue scenarios. From our experiments, we observe that our architecture is able to operate in dynamic and real-time environments, and can handle, in an appropriate and timely manner, any unexpected events that occur. We also comment on the value of our proposed approach for designing adjustable autonomy multi-agent systems and for specific environments such as robotics, where reducing the overall level of communication within the system is crucial.

In this thesis, we explore the topic of designing an architecture and processing algorithms for a multi-agent system, where agents need to address potential unexpected events in the environment, operating under soft real-time constraints. We first develop a classification of unexpected events into Opportunities, Barriers and Potential Causes of Failure, and outline the interaction required to support the allocation of tasks for these events. We then propose a hybrid architecture to provide for agent autonomy in the system, employing a central coordinating agent. Certain agents in the community operate autonomously, while others remain under the control of the coordinating agent. The coordinator is able to determine which agents should form teams to address unexpected events in a timely manner, and to oversee those agents as they perform their tasks. The proposed architecture avoids the overhead of negotiation amongst agent teams for the assignment of tasks, a benefit when operating under limited time and resource constraints. It also avoids the bottleneck of having one coordinating agent making all decisions before work can proceed in the community, by allowing some agents to work independently. We illustrate the potential usefulness of the framework by describing an implementation of a simulator loosely based on that used for the RoboCup Rescue Simulation League contest. The implementation provides a set of simulated computers, each running a simple soft real-time operating system. On top of this basic simulation we implement the model described above and test it against two different search-and-rescue scenarios. From our experiments, we observe that our architecture is able to operate in dynamic and real-time environments, and can handle, in an appropriate and timely manner, any unexpected events that occur. We also comment on the value of our proposed approach for designing adjustable autonomy multi-agent systems and for specific environments such as robotics, where reducing the overall level of communication within the system is crucial.