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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

Gerenciamento ativo de tráfego : estudo de caso de uma autoestrada brasileira

Caleffi, Felipe January 2013 (has links)
Esta dissertação apresenta uma análise da modelagem de estratégias de gerenciamento ativo de tráfego para um estudo de caso de uma autoestrada brasileira. O gerenciamento ativo de tráfego busca de uma forma eficiente melhorar as condições do tráfego durante horários e locais mais congestionados. Esta abordagem consiste em uma combinação de estratégias que aperfeiçoam a operação da infraestrutura existente. Esta dissertação é composta de três artigos, nos quais são apresentados: (i) as tendências atuais de gerenciamento ativo de tráfego, discutindo seus propósitos, definições, benefícios e tendências em novos projetos, (ii) uma análise dos dados coletados no trecho em estudo, que servem de base para a calibração e validação do modelo de simulação, (iii) calibração no software VISSIM do segmento de autoestrada estudado para reproduzir os comportamentos observados em campo, incluindo as velocidades, parâmetros de car following e de troca de faixas e (iv) uma avaliação e quantificação da eficácia da modelagem das estratégias de gerenciamento ativo de tráfego para o trecho em estudo. A calibração do modelo foi um estágio importante da modelagem, pois o trecho modelado possui características especiais quanto ao comportamento do tráfego. Assim, o simular não é capaz de reproduzir naturalmente o trecho em estudo com seus parâmetros default, fazendo-se necessário um esforço de calibração para representar de forma satisfatória as características presentes na rodovia. O tempo de headway e a distância mínima entre os veículos, a agressividade nas trocas de faixa, e nas acelerações e desacelerações foram os parâmetros com maior influência na modelagem. Dados coletados através de filmagens e de coletores com laços indutivos foram usados para calibrar e validar o modelo de simulação. As estratégias de gerenciamento ativo de tráfego empregadas na simulação foram a de harmonização da velocidade e a do uso temporário do acostamento. A modelagem demonstrou que o gerenciamento ativo de tráfego tem impactos positivos na operação do tráfego. Redução de headways, redução nos tempos médios de viagem, na variabilidade dos tempos de viagem e no número de trocas de faixa foram benefícios mensurados. Com o uso das estratégias houve também redução do tempo em que o fluxo da via permanece em colapso, aumentando a eficiência do trecho. / This paper presents an analysis of modeling strategies for active traffic management to a case study of a Brazilian highway. The active traffic management search for an efficient way to improve traffic conditions during the most congested times and locations. This approach consists of a combination of strategies that improve the operation of existing infrastructure. This dissertation consists of three articles in which they are presented: (i) the current trends of active traffic management, discussing its purpose, definitions, benefits and trends in new projects, (ii) an analysis of data collected in the stretch under study, serving as a basis for calibration and validation of the simulation model, (iii) calibration of the VISSIM software for a studied freeway segment to reproduce the behaviors observed in the field, including speeds, car following parameters and lane changes and ( iv) an assessment and quantification of the effectiveness of modeling strategies for active traffic management to the stretch under study. The calibration of the model was an important stage of the modeling, because the modeled stretch has special characteristics as the traffic behavior. Thus, the simulator is not able to naturally simulate the performance under study with its default parameters, making it necessary a calibration effort to represent satisfactorily the features present on the highway. The headway time and the minimum distance between vehicles, aggressiveness in lane changes, and the acceleration and deceleration parameters were most influential in the model. Data collected through filming and collectors with inductive loops were used to calibrate and validate the simulation model. The active traffic management strategies assets employed in the simulation were the speed harmonization and temporary hard shoulder use. The modeling showed that the active traffic management has a positive impact on traffic operation. Reducing headways, reduction in average travel time, variability in travel times and the number of lane changes were measured benefits. With the use of strategies were also reduces the time in which the flow pathway remains collapsed, increasing the efficiency of the stretch.
372

Percepção de diferentes modelos de tipoias utilizadas nas lesões dos ombros : design e ergonomia aplicados ao desenvolvimento de produtos para saúde /

Pereira, Diego Dalvan. January 2020 (has links)
Orientador: João Eduardo Guarnetti dos Santos / Resumo: O ombro por ser uma articulação muito instável está mais vulnerável a lesões. Afim de proteger e imobilizar a articulação o tratamento é seguido com o uso de tipoia. No entanto, a imobilização deixa as articulações sob os efeitos deletérios do desuso, o que pode favorecer o surgimento de lesões secundárias como a capsulite adesiva. O design e a ergonomia são considerados disciplinas científicas capazes de desenvolver e ajustar produtos às necessidades e às capacidades humanas. O objetivo deste estudo foi gerar parâmetros para o design ergonômico de uma tipoia alternativa utilizando as tecnologias de manufatura aditiva, a fim de minimizar os desconfortos termofisiológicos e o índice de capsulite adesiva após imobilização. Nesse contexto, desenvolveu-se com o auxílio do design um modelo de tipoia mais confortável, adequado, funcional e que não favorece o surgimento de complicações após imobilização do ombro. Foi realizada uma coleta de dados com indivíduos adultos, de ambos os gêneros, entre 18 e 85 anos de idade, 71 voluntários, que fizeram uso de tipoia para lesão do ombro. Seguiu com uma investigação ergonômica dos modelos de tipoia disponíveis no mercado, para desenvolver um modelo alternativo com as devidas adequações ergonômicas. O projeto da tipoia foi modelado no software CAD SolidWorks e a impressão foi por FDM (Fusão por Deposição de Material), em uma impressora 3D Creality CR-10, com material PLA (Ácido Polilactico). Para testar a percepção do usuário frente aos mode... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The shoulder because it is a very unstable joint is more vulnerable to injury, in order to protect and immobilize the joint, treatment is followed with the use of a sling. However, immobilization leaves the joints under the harmful effects of disuse, which can favor the appearance of secondary lesions such as adhesive capsulitis. Design and ergonomics are considered scientific disciplines capable of developing and adjusting products to human needs and capacities. The aim of this study was to generate parameters for the ergonomic design of an alternative sling using additive manufacturing technologies, in order to minimize thermophysiological discomfort and the adhesive capsulitis index after immobilization. In this context, a more comfortable, adequate, functional tipoia of model was developed with the aid of design, which does not favor the appearance of complications after shoulder immobilization. A data collection was carried out with adult individuals, both genders, between 18 and 85 years of age, 71 volunteers, who made use of tipoia for shoulder injury. It continued with an ergonomic investigation of the sling models available on the market, to develop an alternative model with the appropriate ergonomic adaptations. The design of the tipoia was modeled in SolidWorks CAD software and the printing was by FDM (Melting by Deposition of Material) in a Creality CR-10 3D printer with PLA material (Polylactic Acid). To test the user's perception of sling models, a semantic diff... (Complete abstract click electronic access below) / Doutor
373

Development of a computational model to study instability and scapular notching in reverse shoulder arthroplasty

Permeswaran, Vijay Niels 01 May 2017 (has links)
Reverse shoulder arthroplasty (RSA) is a common treatment for individuals with arthritis of the glenohumeral joint in the presence of a massive rotator cuff tear. Though this procedure has been effective in restoring function to these individuals, it has also been associated with high early to mid-term complications, such as scapular notching and instability. A finite element (FE) modeling approach has previously been used to study the range of motion an individual with RSA could adduct their arm the polyethylene liner impinged on the inferior scapular bone and the contact stress at the impingement site. This model was then validated in a physical experiment using cadaveric tissue. In this document, I introduce modifications to that FE model to further study instability and scapular notching risk. First, modern RSA implant geometries were introduced into the model, and the effect of polyethylene liner rotation and glenoid version on impingement-free range of motion and instability risk was assessed. Then, a physical material property characterization of rotator cuff tissues present after RSA was performed. Finally, those material properties and continuum elements representative of the rotator cuff tendons were introduced into the FE model. Throughout all of these studies, greater complexity and fidelity was added to improve the ability to model both contact at the impingement site and potential dislocation events through more accurate loadings and boundary conditions.
374

Towards a framework for multi class statistical modelling of shape, intensity, and kinematics in medical images

Fouefack, Jean-Rassaire 10 August 2021 (has links)
Statistical modelling has become a ubiquitous tool for analysing of morphological variation of bone structures in medical images. For radiological images, the shape, relative pose between the bone structures and the intensity distribution are key features often modelled separately. A wide range of research has reported methods that incorporate these features as priors for machine learning purposes. Statistical shape, appearance (intensity profile in images) and pose models are popular priors to explain variability across a sample population of rigid structures. However, a principled and robust way to combine shape, pose and intensity features has been elusive for four main reasons: 1) heterogeneity of the data (data with linear and non-linear natural variation across features); 2) sub-optimal representation of three-dimensional Euclidean motion; 3) artificial discretization of the models; and 4) lack of an efficient transfer learning process to project observations into the latent space. This work proposes a novel statistical modelling framework for multiple bone structures. The framework provides a latent space embedding shape, pose and intensity in a continuous domain allowing for new approaches to skeletal joint analysis from medical images. First, a robust registration method for multi-volumetric shapes is described. Both sampling and parametric based registration algorithms are proposed, which allow the establishment of dense correspondence across volumetric shapes (such as tetrahedral meshes) while preserving the spatial relationship between them. Next, the framework for developing statistical shape-kinematics models from in-correspondence multi-volumetric shapes embedding image intensity distribution, is presented. The framework incorporates principal geodesic analysis and a non-linear metric for modelling the spatial orientation of the structures. More importantly, as all the features are in a joint statistical space and in a continuous domain; this permits on-demand marginalisation to a region or feature of interest without training separate models. Thereafter, an automated prediction of the structures in images is facilitated by a model-fitting method leveraging the models as priors in a Markov chain Monte Carlo approach. The framework is validated using controlled experimental data and the results demonstrate superior performance in comparison with state-of-the-art methods. Finally, the application of the framework for analysing computed tomography images is presented. The analyses include estimation of shape, kinematic and intensity profiles of bone structures in the shoulder and hip joints. For both these datasets, the framework is demonstrated for segmentation, registration and reconstruction, including the recovery of patient-specific intensity profile. The presented framework realises a new paradigm in modelling multi-object shape structures, allowing for probabilistic modelling of not only shape, but also relative pose and intensity as well as the correlations that exist between them. Future work will aim to optimise the framework for clinical use in medical image analysis.
375

Porovnání svalové aktivity vybraných svalů pletence ramenního vyšetřením PEMG u vrcholových plavců a vlivu silového tréninku / Comparison of muscle activity of selected muscles of shoulder girdle by PEMG examination among elite swimmers and influence of strength training

Kubová, Simona January 2020 (has links)
Title of the thesis Comparison of muscle activity of selected muscles of shoulder girdle by PEMG examination among elite swimmers and influence of strength training Thesis aim Analyze and evaluate the influence of strength intervention on muscle activity of selected muscle groups by PEMG during swimming locomotion by crawl method in top swimmers. Methods Fifteen top swimmers specializing in the crawl style at the age of 18-28 years participated in this experiment. After determining pain in the area of the shoulder joint using VAS (Visual Analogue Scale) and the SFPS questionnaire (Swimmer's Functional Pain Scale), which reports about the swimming training, health and analgesic use, probands underwent a PEMG examination of 8 evaluated muscles. Subsequently, they simulated a 100m crawl race on VASA, where PEMG data was again captured. Subsequently, everyone carried out a force intervention program and then again underwent a simulation of the 100m crawl on VASA. The evaluation and processing of the obtained data was performed with the program MyoResearch XP Master Edition from Noraxon company with simultaneous video recording. Basic descriptive statistics, Magnitude Based Difference, ANOVA and Cohen D were used for statistical data processing. Results Muscle activity of the examined muscles increased...
376

Ovlivnění vybraných aspektů pomocí kinesiotapu u problematiky plaveckého ramena / Affection of chosen aspects by using kinesiotape in swimmers shoulder

Laudová, Petra January 2019 (has links)
This research is focused on "swimmer's shoulder" and on affection of chosen aspects by kinesiotape. Theoretical part describes a summary of knowledge about origin, diagnostic and treatment of swimmer's shoulder. Kinesiotaping as a nowadays treatment method and its effects are also specified. The thesis provides a brief description of chosen aspects (pain, tactile acuity and proprioception) and their measuring by objectification methods. Practical part deals with measuring, evaluation and comparing of mentioned aspects before and after treatment by kinesiotape. Methods: 20 competitive swimmers (average age 18,3 years, SD ± 3,10) with shoulder pain were chosen for investigating and measuring. Pain was observed by visual analog scale (VAS) and pressure algometry, tactile acuity by esthesiomether and proprioception by a special method, all before and after treatment. A control group without kinesiotape was included to the research. Results: The experiment showed that tactile acuity was altered in patients with kinesiotape by 27,5 mm in average. This result was evaluated as statistically significant (p = 0,0023). Although values of pain measured by VAS and pressure algometry were enhanced, they were not very significant on the importace level 0,05 (p = 0,1540, resp. 0,1575). Proprioception was also...
377

Scapulafokuserad träning hos crossfitutövare med subacromiell smärta : en single-subject studie / Scapula focused excercise in crossfit athletes with subacromial pain : a single-subject study

Engström, Karolina, Olsson, Karin January 2020 (has links)
Bakgrund: Subacromiell smärta är vanligt hos idrottare med repetitivt arbete ovan axelhöjd, vilket kan orsakas av obalans i muskulatur, förändrad position eller inskränkt rörlighet av scapula. Nedsatt funktion av scapula och dess stabilitet kan leda till minskad axelledsrörlighet och försvagad muskultur i området. Träning är förstahandsalternativet för minskad smärta, förbättrad funktion och ökad rörlighet vid subacromiell smärta. Behandling med scapulafokuserad träning har i dagsläget otillräcklig evidens. Mer studier behövs för att avgöra vilken nedsättning av scapula som den typ av träning påverkar och hur olika scapula fokuserade interventioner påverkar subacromiell smärta. Syfte: Syftet med studien var att undersöka effekten av kombinationsövningen ”shoulder dislocations” vad gäller scapulakontroll, aktiv utåtrotation i axelled och smärta hos crossfitutövare med subacromiell smärta. Metod: Single-subject metod med AB design användes till studien. Tre baslinjemätningar och fyra mätningar under interventionsfasen gjordes, där scapulakontrollen och aktiv utåtrotation i axeln mättes samt smärtskattning utfördes. Deltagarna var sin egen kontroll. Populationen var personer som tränade crossfit vid minst tre tillfällen per vecka med subacromiell smärta. Under interventionen utför deltagarna ”shoulder dislocation” tre gånger per vecka med doseringen tio repetitioner i tre set. Resultatet presenterades i grafer och analyserades visuellt. Resultat: Fyra deltagare inkluderades i studien varav en med bilaterala besvär. Samtliga deltagare förbättrade scapulakontrollen, fyra av fem deltagare förbättrade den aktiva utåtrotationen i axelled. Tre av fem deltagare upplevde minskad smärta under träning och vid mättillfället. Slutsats: ”Shoulder dislocation” tycks förbättra scapulakontrollen, aktiv utåtrotation i axelleden hos crossfitutövare med subacromiell smärta och tendens till minskad smärta. / Background: Subacromial pain is common among overhead athletes, which can lead to muscular imbalance, changed position or decreased mobility of scapula. Reduced function and stability of scapula could lead to decreased shoulder mobility and weakened musculature in the area. Exercise is first hand choice to reduce pain, improve function and increase range of motion at subacromial pain. Treatment with scapular focused exercise is today limited. More studies are needed to determine what kind of reduction of scapula this exercise influences and how different scapular focused interventions affect subacromial pain. Aim: The purpose of the study was to examine the effect of the combination exercise ”shoulder dislocations” in terms of scapula control, active external rotation in the glenohumeral joint and pain in crossfit athletes with subacromial pain. Method: Single-subject method with AB design was used in the study. Three baseline measurements and four measurements during the intervention phase was collected, where control of scapula, active external rotation and pain was measured. Participants were their own control. The population was individuals who trained crossfit at least three times a week and had subacromial pain. During the intervention the participants performed ”shoulder dislocations”. Performing three sets of ten repetitions three times a week. The results were presented in graphs and visually analyzed. Results: Four participants were included in the study whereof one had bilateral disorders. All participants increased control of scapula, four out of five increased active external rotation of the glenohumeral joint. Three out of five participants experienced pain reduction during exercise and at the time of measurement. Conclusion: ”Shoulder dislocations” seems to improve control of scapula and active external range of motion of the glenohumeral joint in crossfit athletes with subacromial pain.
378

Seasonality on Gotland - a local business perspective

Svensson, Petter January 2020 (has links)
Seasonality in tourism has been present in the literature for decades. It is a universally phenomenon connected to climate and institutional factors which contributes to an imbalance in demand. It can be expressed through numbers of tourists, bed nights and expenditure. Seasonality is most obvious in peripheral destinations and it has generally been described as an issue that needs to be solved. Previous studies have put much attention on macro levels which includes how destinations could mitigate seasonality and create all-year around tourism. This study examines seasonality at a micro level by using Gotland as a case. The aim of the study was to explore perspective of Gotlandic nature-based tourism companies on seasonality, all in order to increase the understanding on seasonality aspects in tourism. The data collection was performed through semi-structured interviews with nature-based companies on Gotland. The results of the study indicate that lifestyle motives are strong for running a nature-based company on Gotland and the short, intense summer-season make it possible. Seasonality is therefore not considered as an issue that needs to be urgently solved. Other themes related to sustainable destination development such as carrying capacity, employment, possibilities of growth and regional strategies are also being deeply discussed in this study.
379

Rotator Cuff-Related Pain: Patients' Understanding and Experiences

Gillespie, Melissa A., Mącznik, Aleksandra, Wassinger, Craig A., Sole, Gisela 01 August 2017 (has links)
Background Persistent musculoskeletal pain is a multi-factorial entity, influenced by biological, genetic and psychosocial factors. Psychosocial factors, such as individuals' beliefs and experiences, need to be considered in the management of such pain. While extensive research has explored beliefs of individuals with spinal pain, less is known about individuals' beliefs regarding shoulder pain. Objectives To explore beliefs about the cause of pain in individuals with persistent rotator cuff-related pain, as well as the experiences of the effect of pain on their daily lives. Design A mixed methods design, using semi-structured interviews and validated outcome questionnaires. Method Five men and five women, aged 47–68 years, with shoulder pain for at least three months were recruited. Individual semi-structured interviews were audio-recorded, transcribed verbatim and analysed using the general inductive approach. Results/findings Four key themes emerged. The cause of pain, ‘Understanding the pain’, was described in terms of anatomical factors within the context of the participants' lives. The pain impacted all areas of life, creating another theme, ‘It affects everything’. Participants responded to their pain by adopting certain, ‘Pain-associated behaviours’ and sought information for diagnosis, general management and exercise prescription, ‘Emotional responses and the future’. Conclusions The participants with rotator cuff-related pain believed the cause of their pain to be local to the shoulder region. However, they also described various stressors in their work-, sports- and family-related lives. Rehabilitation may need to include educating the individual, expanding their understanding regarding pain mechanisms and appropriate interventions, based on individual goal-setting.
380

Humeral Retrotorsion in Developing Children and its Relationship to Throwing Sports

Greenberg, Elliot M 01 December 2015 (has links)
Background: Baseball players exhibit a more posteriorly oriented humeral head or humeral retrotorsion (HRT) in the dominant arm, likely representing an adaptive response to the stress of throwing. This adaptation is thought to occur while skeletally immature, however there is limited research detailing how throwing while young influences the development HRT. In addition, it is currently unclear how this changing osseous orientation influences shoulder motion within young athletes. Purpose: To determine the influence of throwing and age on the development of asymmetry in HRT and shoulder range of motion (ROM); and analyze the relationship between HRT and ROM. Study Design: Cross-sectional age matched study Methods: Healthy athletes (8-14 years-old) were categorized into two groups based upon sports participation; throwing group (n=85) and non-throwing group (n=68). Bilateral measurements of HRT, shoulder external (ER), internal rotation (IR) and total range of motion (TROM) at 90° were performed using diagnostic ultrasound and digital inclinometer. A two-way analysis of variance was performed with throwing status (yes/no) and age group (youth (8-10.5), junior (10.51-12) and senior (12.01-13.99)) as primary factors. Dependent variables were asymmetry (dominant-non-dominant) in HRT,ER, IR and TROM. The relationship between ROM and HRT was analyzed using Pearson correlation coefficients. Results: Throwing athletes demonstrated a larger degree of HRT on the dominant side, resulting in greater asymmetry (8.7° versus 4.6°). Throwing athletes demonstrated a gain of ER (5.2°), a loss of IR (6.0°) and no change in TROM when compared to the non-dominant shoulder. Pairwise comparisons identified altered HRT and shoulder ROM in all age groups of throwers. A significant but weak relationship between HRT and shoulder ROM existed. Conclusion: Throwing causes adaptive changes in HRT and shoulder ROM in youth baseball players at a very young age. Other factors in addition to HRT influence shoulder motion within this population. Clinical Relevance: In baseball players, an altered arc of motion can be expected at a young age. This adaptation is in part due to changes in osseous structures, however a larger component of change is likely due to other factors.

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