Tesi sul tema "Interrupted times series analysis"

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1

Prendergast, Tim. "Interrupted Time Series Analysis Techniques in Pharmacovigilance". Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/30291.

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This thesis considers an approach to evaluate the effectiveness of risk communications for prescription drugs by performing interrupted time series analysis of prescription drug volumes prior to and after the risk communication date. The paper presents methods for detecting change in the presence of autocorrelation and techniques to reduce bias in estimation. Statistical results and data plots are presented for 63 data series. Size and power of the statistical techniques are considered, and a correspondence analysis between these statistical techniques and a small group of physicians is performed. The methods considered in this thesis correspond weakly with physician sentiment, and exhibit inflated type I errors in the presence of significant autocorrelation.
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2

Gerlach, Laura A. "Increasing Organ Donations in Maryland: An Interrupted Time Series Analysis". ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/5707.

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The state of Maryland has been unsuccessful in achieving its goal of registering all of its population as organ donors. The purpose of this correlational study was to understand if allowing registered donors to remain anonymous would increase donor registration rates. The theoretical foundation of this study was the theory of planned behavior. Data were collected from the Motor Vehicle Administration of Maryland and the Division of Motor Vehicle of Virginia. The data were analyzed using regression displacement, interrupted time series analysis, auto correlation analysis, and Arima Box Jenkins methodology. According to the study findings, offering the option to remain anonymous and registering to be an organ donor with no heart icon on the driver's license did not have the immediate effect of encouraging more people to register as an organ donor. Parameter estimates from an Arima autoregression analysis did suggest that the impact of the removal of the heart icon may have a delayed impact, although data availability limited attempts at further investigation.
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3

Donnelly, Neil James Public Health &amp Community Medicine Faculty of Medicine UNSW. "The use of interrupted time series analysis to evaluate the impact of Pharmaceutical Benefits Scheme policies on drug utilisation in Australia". Awarded by:University of New South Wales. Public Health and Community Medicine, 2005. http://handle.unsw.edu.au/1959.4/22509.

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PROBLEM INVESTIGATED: Methodological issues and policy implications arising from the application of interrupted time series (ITS) analyses to assess the impact of Pharmaceutical Benefit Scheme (PBS) subsidisation policies on drug utilisation in Australia. PROCEDURES FOLLOWED: A critical review of methodological issues relating to the application and analysis of ITS designs was undertaken. This included an examination of drug utilisation data sources in Australia. The PBS policies examined were: (i) the introduction of copayments in 1990; (ii) the introduction of re-supply limits in 1994 and (iii) the introduction of a form of reference pricing in 1998. Monthly aggregate drug utilisation data was obtained from the Australian Department of Health and Ageing. Segmented regression analyses incorporating autocorrelated errors were implemented and statistical diagnostics applied to ensure correct ITS model specification. Alternative seasonal modelling approaches were compared. RESULTS OBTAINED: The copayment ITS evaluation found that while these copayments produced a reduction in the utilisation of essential and discretionary medications, this effect was stronger for discretionary drugs. An unintended policy effect was a large anticipatory increase in drug utilisation during the month prior to the copayments. Repatriation PBS data was also utilised due to the limited number of pre-intervention data points in the Community series. The re-supply limit ITS evaluation found that the 20-day rule markedly reduced the size of the seasonal increase during the month of December. However, logistic regression analyses showed that the size of this reduction attenuated over time, highlighting the need to consider alternative analysis strategies when applying a ITS approach. The reference pricing ITS evaluation found that this policy had achieved its drug utilisation objectives for H2RAs and ACE Inhibitors. However with regard to CCBs, no increase in the utilisation of benchmark priced drug was apparent, which probably reflected clinical concerns at the time about the safety of these drugs. MAJOR CONCLUSIONS: Well implemented ITS analyses provide a valuable tool for evaluating the impact of PBS subsidisation policy change on drug utilisation in Australia. As with any methodology, however, different design and data integrity issues will affect the quality of information provided.
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4

Hummelgren, Axel. "Vilket pris avgör vad du handlar? : En kvantitativ jämförande studie av krympflations påverkan på försäljning". Thesis, Uppsala universitet, Nationalekonomiska institutionen, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-419854.

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Konsumtionsbeteende är idag en viktig undersökningspunkt för att med säkerhet kunna genomföra implementeringar av nya policys inom konsumentpolitiken. Både klassiska nationalekonomiska teorier och beteendeekonomiska teorier används för att beskriva och förutsäga dessa beteenden, men det saknas undersökningar på deras faktiska kopplingar till olika typer av prissättning. Denna uppsats har gjort ett försök till att undersöka vilken påverkan en förändring i pris genom en förändring i paketstorlek har på efterfrågan. Den har även försökt ge en analys till om de förändringar som noteras är kopplade till beteendeekonomi eller klassisk nationalekonomisk teori. Med hjälp av en vanlig tidstrendsanalys tillsammans med en interrupted-time-series-analysis har försäljningstrenderna för försäljning i KG för två substituerande produkter skapats och jämförts. Dessa fastställer att förändringens påverkan framförallt stämmer överens med teorier gällande beteendeekonomi men att sambandet mellan en förändring i försäljningsnivå och en förändring i paketstorlek inte är säkerställt. Analyserna gjorda i denna studie blir därför inte fastställda och möjligtvis otillräckliga för att besvara den fråga som ställts. Jag som författare vill därför uppmana till att flera utvecklande studier inom ämnet bör utföras för att säkerställa möjliga resultat.
Consumer behaviour is today an important aspect of making quality decisions regarding policies on the consumer market. Both classical economical models and behavioural economical models are used to describe and predict these kinds of behaviours. Although todays studies on their connections to different methods of pricing are lacking. This paper tries to investigate what kind of impact a change in price by changing the size of the good has on demand. It also tries to produce an analysis on if this impact is connected with bevioural or classical economic theories. Based on a classical time-trend analysis together with an interrupted-time-series-analysis different trends for sales in KG regarding two substitutional products have been created. These determine that the effects on demand are most likely connected to behavioural economics but that the effects aren’t statistically significant. The analysis done in this paper therefore cannot be statistically determined and indicates that further studies on the subject need to be done to answer these questions with more certainty.
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5

Bonander, Carl. "Searching for causal effects of road traffic safety interventions : applications of the interrupted time series design". Licentiate thesis, Karlstads universitet, Institutionen för miljö- och livsvetenskaper, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-35781.

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Traffic-related injuries represent a global public health problem, and contribute largely to mortality and years lived with disability worldwide. Over the course of the last decades, improvements to road traffic safety and injury surveillance systems have resulted in a shift in focus from the prevention of motor vehicle accidents to the control of injury events involving vulnerable road users (VRUs), such as cyclists and moped riders. There have been calls for improvements to the evaluation of safety interventions due to methodological problems associated with the most commonly used study designs. The purpose of this licentiate thesis was to assess the strengths and limitations of the interrupted time series (ITS) design, which has gained some attention for its ability to provide valid effect estimates. Two national road safety interventions involving VRUs were selected as cases: the Swedish bicycle helmet law for children under the age 15, and the tightening of licensing rules for Class 1 mopeds. The empirical results suggest that both interventions were effective in improving the safety of VRUs. Unless other concurrent events affect the treatment population at the exact time of intervention, the effect estimates should be internally valid. One of the main limitations of the study design is the inability to identify why the interventions were successful, especially if they are complex and multifaceted. A lack of reliable exposure data can also pose a further threat to studies of interventions involving VRUs if the intervention can affect the exposure itself. It may also be difficult to generalize the exact effect estimates to other regions and populations. Future studies should consider the use of the ITS design to enhance the internal validity of before-after measurements.
Traffic-related injuries represent a global public health problem, and contribute largely to mortality and years lived with disability. Over the course of the last decades, improvements to road traffic safety and injury surveillance systems have resulted in a shift in focus from motor vehicle accidents to injury events involving vulnerable road users (VRUs), such as cyclists and moped riders. There have been calls for improvements to the evaluation of safety interventions due to methodological problems associated with the most commonly used study designs. The purpose of this licentiate thesis was to assess the strengths and limitations of the interrupted time series (ITS) design, which has gained some attention for its ability to provide valid effect estimates while accounting for secular trends. Two national interventions involving VRUs were selected as cases: the Swedish bicycle helmet law for children under the age 15, and the tightening of licensing rules for Class 1 mopeds. The empirical results suggest that both interventions were effective. These results are discussed in the light of some methodological considerations regarding internal and external validity, data quality and the ability to fully understand key causal mechanisms behind complex interventions.
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6

Akbari, Ayub. "Change in Referral Patterns to Nephrologists after Estimated Glomerular Filtration Rate (eGFR) Reporting: An interrupted time series analysis". Thesis, University of Ottawa (Canada), 2011. http://hdl.handle.net/10393/28785.

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Objectives: To update a Cochrane review of interventions to improve outpatient referral and to assess changes in referrals to nephrologists after initiating automatic estimated glomerular filtration rate (eGFR) reporting. Methods: Systematic review using standardized Cochrane methods. Before and after study with interrupted time series analysis using data from retrospective chart review on referrals from family medicine to nephrology. Results: Review added one new study and removed one for total of 17 studies. Referrals improved with education and structured referral sheets. Of 2766 eligible referrals for one-year pre-eGFR reporting to one-year post, 96.6% were reviewed. There was a 68.2% increase in referrals for chronic kidney disease (P < 0.01) and a 64.1% increase in total appropriate referrals (P =0.01) with no significant change in proportion of appropriate referrals (-2.5%, P=0.56). Conclusion: Systematic review findings did not change from the previous review. eGFR reporting increased both appropriate and inappropriate referrals.
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7

Condron, Aaron. "An impact evaluation of u.s. arms export controls on the u.s. defense industrial base an interrupted time-series analysis". Honors in the Major Thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/363.

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The United States Defense Industrial Base (USDIB) is an essential industry to both the economic prosperity of the US and its strategic control over many advanced military systems and technologies. The USDIB, which encompasses the industries of aerospace and defense, is a volatile industry - prone to many internal and external factors that cause demand to ebb and flow widely year over year. Among the factors that influence the volume of systems the USDIB delivers to its international customers are the arms export controls of the US. These controls impose a divergence from the historical US foreign policy of furthering an open exchange of ideas and liberalized trade. These controls, imposed by the Departments of Commerce, Defense, and State rigidly control all international presence of the Industry. The overlapping controls create an inability to conform to rapidly changing realpolitiks, leaving these controls in an archaic state. This, in turn, imposes a great deal of anxiety and expense upon managers within and outside of the USDIB. Using autoregressive integrated moving average time-series analyses, this paper confirms that the implementation of or amendment to broad arms export controls correlates to significant and near immediate declines in USDIB export volumes. In the context of the US's share of world arms exports, these controls impose up to a 20% decline in export volume.
B.S.B.A.
Bachelors
Business Administration
Finance
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8

Kylén, Linda. "Utvärdering av mötesfria vägar : Analys av olyckor på mötesfria vägar i Karlstadsregionen". Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-33081.

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Sedan år 1998 har det i Nollvisionens fotspår startats ett utvecklingsprogram i Sverige som syftar till att omvandla gamla 13 meters landsvägar och motortrafikleder till mötesfria. Implementeringen var tänkt att påtagligt reducera antalet mötes- och omkörningsolyckor samt singelolyckor med svåra konsekvenser i form av svårt skadade och dödade utan att försämra trafiksäkerheten i övrigt. Syftet med denna studie är att göra en effektmätning av de mötesfria vägarnas införande i Karlstadsregionen samt att göra en sammanställning av de olycksrisker mötesfria vägar omfattas av. Frågeställningarna som används i studien är: - Har det blivit säkrare på vägarna sedan implementeringen av mötesfria vägar i Karlstadsregionen? - Hur sker olyckor på mötesfria vägar inom Karlstadsregionen?  För att beskriva hur olyckor sker på mötesfria vägar inom Karlstadsregionen har en deskriptiv analys tillämpats som grundats på de beskrivningar av händelseförlopp som dokumenterats i STRADA och CORE, mellan åren 2010-2013. För att avgöra huruvida vägarna blivit säkrare sedan implementering tillämpades en segmenterad linjär regressionsanalys där antalet personskadeolyckor studerats, tre år innan och tre år efter ombyggnad för respektive vägavsnitt. Singel- och upphinnandeolyckor var de dominerande olyckstyperna på mötesfria vägar i Karlstadsregionen mellan åren 2010-2013 då de sammanlagt stod för 72,3% av samtliga olyckor som medfört skada. Vid kategoriseringen av huvudorsak till olycka framgick det att 42% av alla olyckor kan spåras till brister i samspel mellan trafikanter och väderförhållanden bedömdes i 24,1% av fallen vara huvudorsak till olycka. Den statistiska analysen var inte signifikant, men gav indikation på att vägarna blivit säkrare sedan implementering då trenden för samtliga skadade minskat.
In the footsteps of Vision Zero, a development program in Sweden was initiated in 1998. The program aimed to increase road safety on existing 13-meter roads and express roads by implementing median barriers. The purpose of this study is to measure the impact of the transformed roadways in the Karlstad region and to examine the different types of accident risks the roadways are covered by. The research questions used are: - Has the implementation of median barriers in the Karlstad region contributed to safer roads? - How do accidents occur on roads with median barriers? To describe how accidents occur on roads with median barriers in Karlstad region a descriptive analysis was made by the description of event that is documented in STRADA and CORE, between the years 2010-2013. To determine whether the roads became safer after implementation a segmented linear regression analysis was applied. Accidents resulting in injury were examined, three years before and three years after reconstruction for each road section. Single-vehicle accidents and rear-end collisions were the dominating accident types on roadways with median barriers in the Karlstad region between the years 2010-2013. They together accounted for 72,3% of all accidents that resulted in injury. When the main cause of accident was examined, it emerged that 42% of all accidents could be traced to deficiencies in the interaction between road users. Weather conditions were estimated to be the main cause of accident in 24,1% of all the studied cases. The statistical analysis was not significant, but indicated that the roads became safer after the implementation since the observed trend for all types of injured decreased.
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9

Afonso, Eliane Terezinha. "Impacto da vacinação com a PCV10 na morbidade hospitalar por pneumonia no Brasil: análise de série temporal interrompida". Universidade Federal de Goiás, 2015. http://repositorio.bc.ufg.br/tede/handle/tede/5507.

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BACKGROUND: Pneumonia causes substantial morbidity and mortality in all age groups around the world. The 10-valent pneumococcal conjugate vaccine (PCV10) was introduced into the routine infant immunization in Brazil, free of charge, in March 2010. The aim of this study was to evaluate the impact PCV10 vaccination on rates of all cause pneumonia hospitalizations one year and three years after its introduction in Brazil. METHODS: We conducted two interrupted time series analysis studies. The first evaluated only the direct effect of PCV10 vaccination, in five Brazilian cities (Belo Horizonte, Curitiba, Porto Alegre, São Paulo and Recife), and was conducted one year after starting the vaccination. The second study evaluated the direct and indirect impact (individuals not vaccinated) of PCV10 vaccination in Brazil, and was conducted three years after vaccination. We used data from the Brazilian Hospitalization System from 2005-2013. The main outcome was monthly rates of all-cause pneumonia hospitalizations identified by ICD-10 codes J12-J18. We used hospitalization rates for congenital malformations and non-respiratory causes as a comparison groups. The time-series analysis was based on a generalized linear model. Pneumonia rates observed in the pre-vaccination period were used to estimate the hospitalization rates in the post-vaccination period of each study, adjusting for seasonality and secular trends. To estimate the direct (2-23 months of age) and indirect (≥5 years of age) impact of PCV10 vaccination, we calculated the percentage change in hospitalization rates, as the observed divided by the predicted rates of hospitalization in the post-intervention period minus one, with respective 95% CI and p values. The number of all-cause pneumonia hospitalizations averted by vaccination was calculated taking into account the difference between the predicted and observed number in the PCV10 post vaccination period. RESULTS: One year after introduction of PCV10 in Brazil, significant declines in hospitalizations for pneumonia in children aged 2-23 months were noted in Belo Horizonte (28.7%), Curitiba (23.3%), and Recife (27.4%). After three years of the introduction of PCV10, 461,519 pneumonia hospitalizations were averted in Brazil, and a significant decrease in rates of pneumonia hospitalization was observed in unvaccinated individuals aged 5-39 years, ranging from 14.1-17.4% (p<0.05). In contrast, an increased trend in pneumonia hospitalizations (p=0·004) was observed for elderly (≥ 65 years). CONCLUSION: Vaccination with PCV10 in Brazil was associated with reduction of pneumonia hospitalizations in vaccinated individuals. Herd effect was observed in individuals aged 5-39 years after three years of vaccination. Potential reasons for the increased trend in pneumonia hospitalization rates in the elderly should be investigated.
INTRODUÇÃO: As pneumonias contribuem com alta carga de morbimortalidades em todo mundo. No Brasil, a vacina pneumocócica conjugada 10 valente (PCV10) foi introduzida na rotina de imunização da infância em março de 2010. Este estudo teve como objetivo avaliar o impacto da vacinação nas taxas de hospitalizações por pneumonia no Brasil no curto e médio prazo do início da vacinação. METODOLOGIA: Dois estudos de séries temporais interrompidas foram conduzidos. O primeiro avaliou o efeito direto da vacinação em cinco capitais brasileiras (Belo Horizonte, Curitiba, Porto Alegre, São Paulo e Recife) e foi conduzido após um ano de introdução da PCV10 no país. O segundo estudo avaliou o impacto direto e indireto (população não vacinada) da vacinação em todo país e foi conduzido três anos após sua introdução. Os dados de hospitalizações foram obtidos do Sistema de Informações Hospitalares (SIH-SUS) de 2005 a 2013. O desfecho principal foi a taxa mensal de hospitalização por pneumonia definida pelos códigos J12-J18 da CID10. As taxas de hospitalizações por malformações congênitas e causas não respiratórias foram utilizadas como grupos de comparações. A análise de série temporal utilizou um modelo de regressão linear generalizado. As taxas de hospitalizações por pneumonia observadas no período pré-PCV10, ajustadas por tendência secular e sazonalidade, foram utilizadas para estimar as taxas no período pós-PCV10. O impacto da vacinação para cada faixa etária foi calculado como o percentual de mudança nas taxas de hospitalizações, dividindo-se as taxas observadas pelas taxas preditas do período pós PCV10, menos um. Os respectivos IC95% e os valores de p foram apresentados. O número de hospitalizações por pneumonia evitadas após três anos de vacinação foi estimado pela diferença entre os números de hospitalizações por pneumonia preditos e observados no período pós-vacinação. RESULTADOS: Após um ano de introdução da PCV10 no Brasil, observou-se significativo declínio nas taxas de hospitalizações por pneumonia em crianças de 2 a 23 meses em três das cinco capitais estudadas: Belo Horizonte (28,7%), Curitiba (23,3%), e Recife (27,4%). Após três anos da introdução da PCV10, 461.519 hospitalizações por pneumonia foram evitadas no Brasil e um significativo declínio nas taxas de pneumonia foi observado em indivíduos não vacinados de 5 a 39 anos variando de 14,1% a 17,4% (p<0,05). No entanto, observou-se um aumento significativo (9,9%, p=0,004) nas taxas de hospitalizações por pneumonia para idosos ≥65 anos. CONCLUSÕES: A vacinação com a PCV10 foi associada à significativa redução das hospitalizações por pneumonia na infância. Adicionalmente, o estudo evidenciou importante redução das hospitalizações por pneumonia em grupos etários não vacinados, sinalizando efeito indireto conferida pela vacina. A tendência de aumento das hospitalizações por pneumonias em idosos necessita de investigações para elucidação dos fatores envolvidos nesse fenômeno.
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Burger, Eric C. "A multivariate times series analysis of U.S. Army recruiting". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2000. http://handle.dtic.mil/100.2/ADA379705.

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Thesis (M.S. in Operations Research)--Naval Postgraduate School, June 2000.
Thesis advisor(s): Buttrey, Samuel E. "June 2000." Includes bibliographical references (p. 89-90). Also available in print.
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Rios, Benavides Renato, e Chrysafis Bourelos. "Times Series Analysis of Calibrated Parameters of Two-factor Stochastic Volatility Model". Thesis, Mälardalens högskola, Akademin för utbildning, kultur och kommunikation, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-44644.

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Stochastic volatility models have become essential for financial modelling and forecasting.The present thesis works with a two-factor stochastic volatility model that is reduced to four parameters. We start by making the case for the model that best fits data, use that modelto produce said parameters and then analyse the time series of these parameters. Suitable ARIMA models were then used to forecast the parameters and in turn, the implied volatilities.It was established that fitting the model for different groups of maturities produced better results. Moreover, we managed to reduce the forecasting errors by forecasting according to the different maturity groups.
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Tomich, Lísia Gomes Martins de Moura. "Impacto da vacinação contra o meningococo C na morbidade da doença meningocócica". Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/6289.

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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
INTRODUCTION: Routine infant immunization with meningococcal C conjugate vaccine (MenC-V) started in Brazil in November 2010, administered at three, five and 12 months of age with no catch-up for older age-groups. However, by March 2010, a vaccination campaign with MenC-V was performed in Salvador in individuals under five years-old, and from 10 to 24 yearsold. In São Paulo state, the outbreaks occurred in teenagers and young adults prompting one-time vaccination campaign from 2010 to 2014 targeting these age-groups. OBJECTIVE: To assess the direct and indirect impact (herd effect) of vaccination on invasive meningococcal disease (MD) for capsular group C (MenC) four years after the introduction of MenC-V in three scenarios: i) Brazil as a whole (routine vaccination in childhood only); ii) Brazil except for Salvador (vaccination campaign with teenagers during the year of MenC-V introduction); and iii) São Paulo state (vaccination campaign for adolescents and young adults during 2010-2014 to control outbreaks). METHODS: We performed an ecological quasi-experimental design from 2008 to 2014 using data from the National Reference Laboratory for Meningitis, and data from the National Information System for Notifiable Diseases. A deterministic linkage was performed between the two databases to improve the accuracy of the detection of MD, especially in capsular groups. An interrupted time-series analysis was conducted using the Holt-Winters technique to control for pre-existing trends and seasonal variations. The MenC vaccination impact was evaluated as the percentage of reduction in the incidence rates of MenC in the post-vaccination period (2012 to 2014), using the pre-vaccination period (2008 to 2010) to estimate what would be expected on the post-vaccination period, whether the vaccination had not been introduced. For Salvador, we analyzed the effect of the vaccination on the number of MenC cases. RESULTS: A total of 18,136 invasive MD cases were analyzed. For Brazil as a whole, the vaccination reduced 67.4% (lower 95%CI 42.5%) the rates for MenC for infants under 12 months, 92.3% (lower 95%CI 77.7%) for the age-group 12-23 months, and 65.7% (lower 95%CI 28%) for children aged 2-4 years. Indirect impact (20-24.7%) was observed in the age-group 5-19 years. When excluding Salvador from the analysis of Brazil, the indirect impact was observed only for children in the age-group 5-9 years. In the scenario of São Paulo state, similarly to Brazil, significant impact was observed in the target age-groups, in addition to indirect impact in the age group 5-9 years. In Salvador, in addition to the effect on the vaccinated population a sharp and sustainable decline of MenC cases was observed in all age-groups not target for vaccination. Overall, 1,170 cases of MenC were averted in Brazil after the introduced of Men-C vaccination. CONCLUSION: The strategy of catch-up for adolescents and young adults, especially during the year of MenC-V introduction may lead to rapid and sustainable herd effect.
A vacina meningocócica conjugada contra o grupo capsular C (MenC-V) foi introduzida no calendário de imunização infantil brasileiro em novembro de 2010, sendo administrada aos três, cinco e 12 meses de idade sem catch-up para os demais grupos etários. Entretanto, em março de 2010, uma campanha de vacinação com MenC-V foi realizada em Salvador para indivíduos menores de cinco anos de idade e de 10 a 24 anos. No estado de São Paulo os surtos ocorreram em adolescentes e adultos jovens, determinando campanhas de vacinações de bloqueio nessa faixa etária nos anos de 2010 a 2014. OBJETIVO: Avaliar o impacto direto e indireto (rebanho) da vacinação nas taxas de incidência de doença meningocócica (DM) invasiva pelo grupo capsular C (MenC) após quatro anos da introdução da MenC-V em três cenários: i) Brasil como um todo (imunização de rotina somente de crianças); ii) Brasil exceto Salvador (campanha de vacinação em adolescentes no ano de introdução da MenCV); e iii) estado de São Paulo (vacina de rotina na infância e vacinações de bloqueio em adolescentes e adultos jovens para controlar surtos). MÉTODOS: Foi realizado um estudo ecológico quasi-experimental para avaliar o impacto da vacinação em série histórica de 2008 a 2014 usando os bancos de dados do Laboratório Nacional de Referência para Meningites Bacterianas, Instituto Adolfo Lutz (IAL) e o Sistema de Informação de Agravos de Notificação (Sinan). Um processo de vinculação (linkage) determinístico entre as duas bases foi realizado para melhorar a acurácia da detecção de casos de DM, especialmente de grupo capsulares. Uma análise de série temporal interrompida foi conduzida utilizando a técnica de Holt-Winters para controlar por tendência pré-existente e variações sazonais. O desfecho foi taxa de MenC. O impacto da vacinação foi avaliado pelo percentual de redução da incidência de MenC no período pós-vacinal (2012 a 2014), utilizando o período pré-vacinal (2008 a 2010) para estimar o que seria esperado no período pós-vacinal, caso a vacinação não tivesse sido introduzida. Para Salvador foi analisado o efeito da MenC-V no número de casos de MenC. RESULTADOS: Um total de 18.136 casos de DM invasiva foram analisados. Para o Brasil como um todo, a vacinação reduziu significativamente a DM por MenC na faixa etária alvo, com redução de 67,4% (limite inferior do IC95% 42,5%) em menores de 12 meses, 92,3% (limite inferior do IC95% 77,7%) para faixa etária de 12-23 meses e 65,7% (limite inferior do IC95% 28%) em crianças de 2-4 anos, e efeito rebanho foi observado na faixa etária de 5 a 19 anos com 20-24,7%. Quando se exclui Salvador na análise do Brasil, impacto indireto significativo foi observado somente em crianças de 5-9 anos. No cenário São Paulo, semelhante ao Brasil, observou-se impacto estatisticamente significante nas faixas etárias alvo do PNI, além do efeito rebanho na faixa etária de 5-9 anos de idade. Para Salvador, o impacto da vacinação apresentou um declínio acentuado e sustentável em todas as faixas etárias fora do alvo da vacinação. Ao todo, 1.170 casos de MenC foram evitados no período estudado. CONCLUSÃO: A estratégia de vacinação de catch-up em adolescentes e adultos jovens, especialmente no ano de introdução da MenC-V, promoveu um rápido e sustentável rebanho.
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13

Meliane, Walid. "Applied time series analysis for forecasting process cycle times and process yields in the semiconductor manufacturing industry". Thesis, University of Ottawa (Canada), 1995. http://hdl.handle.net/10393/10331.

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Complementary metal oxide semiconductor (CMOS) integrated circuits (ICs) are the dominant technology in the semiconductor industry. Meeting delivery date is important to ensure customer satisfaction and maintain momentum between manufacturing divisions. Two major concerns are to produce the right quantity of ICs in the expected period of time. Yield and cycle time are two critical parameters used to assess process performance. The main objectives of this work were to obtain reliable forecasts of yields and cycle times and to monitor the process for detection of upsets. We explored the use of time series models such as ARIMA, transfer function and intervention models. A simultaneous outlier treatment and forecasting strategy was developed which combined the joint estimation of model parameters and outlier effects procedure with some new control charts. This method is particularly suited for highly correlated processes that are frequently subjected to large outliers. Choice of time basis was an important issue in this work (i.e., week of emergence from or entrance to the process). For ARIMA modeling, cycle time series were found to follow a highly correlated AR(1) process whereas yield series were just white noise. Five-step ahead ARIMA forecasts were often inaccurate due to the presence of frequent and large outliers. One step-ahead ARIMA forecasts were quite satisfactory. Transfer function models relating yield data to the process capacity data were built. Transfer function models for overall process cycle times were constructed using as inputs cycle times for various stages in the process. Five step-ahead forecasts were highly improved using these transfer functions. (Abstract shortened by UMI.)
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14

Kurz, Verena. "Municipal waste management in times of economic downturn - the case of the Växjö Municipality (Sweden)". Thesis, Växjö University, School of Management and Economics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-5572.

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This paper is analysing the development of municipal waste amounts in theSwedish municipality of Växjö. The cause of the analysis were decliningwaste amounts in the second half of 2008, which was a rather atypical developmentsince in the years before, a steady growth could be observed.Therefore, the Waste management department in Växjö raised the questionif and in what way the economic downturn that Sweden is currently undergoingcould affect the waste amounts. This is the central question I try toanswer in this paper. To pursue a systematic analysis, I start with a theoreticalsection on how waste is generated in societies, how waste is managed inSweden and which factors influence the development of municipal waste.Aim of this section is to give a theoretical assessment on how the economicdownturn could affect the actual waste amounts. Then, an empirical analysisof Växjö’s municipal waste amounts is conducted. This is done by timeseries modelling of monthly amounts, by using the ARIMA methodology.The models then are tested on structural breaks that could be attributed to aneconomic downturn. Finally, the waste amounts for the next twelve monthsare forecasted.

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15

Abitante, Kleber Giovelli. "Modelos de séries temporais aplicados à análise prospectiva de concessão de crédito bancário". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/11/11132/tde-24042007-135316/.

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O presente trabalho teve por objetivo modelar as séries de concessão de crédito bancário às pessoas físicas, às pessoas jurídicas e para financiamento de atividades rurais, bem como realizar previsões a cerca dos comportamentos destas séries. A metodologia utilizada foi de Auto- Regressão Vetorial. A propriedade de co-integração entre as variáveis foi considerada no trabalho, sendo que foram estimados modelos de Auto-Regressão Vetorial com Correção de Erro – VEC. Os resultados mostram que o produto, a taxa de juros cobrada nos empréstimos, as exportações e as vendas no varejo podem auxiliar na geração de previsões satisfatórias das concessões de crédito às pessoas jurídicas e às pessoas físicas. Para o modelo de previsão das concessões de crédito para financiamento de atividades rurais, utilizaram-se variáveis referentes à produção de fertilizantes, vendas de tratores e colheitadeiras, produção de leite e produção de carnes bovina, suínas e de aves, sendo que as previsões geradas pelo modelo apresentaram performance adequada, dada a dificuldade da modelagem.
The aim of this study was to model the series of banking credit concessions to individuals, to firms and for rural activities financing, and to generate forecasts about the behavior of that series. The methodology used was the Vector Auto-Regression. The property of co-integration among the variables was considered, and were estimated Vector Auto-Regression models with Error Correction – VEC. The results shows that the product, the lending interest rate, the exportation and the retail sales can to help on the generation of satisfactory forecast of the banking credit concessions to firms and to individuals. Regarding the forecast model of the banking credit concessions for rural activities financing, was used variables about the fertilizers production, sales of tractors and harvesters machines, milk production and the production of meat of cattle, pork and chicken, and the forecasts generated by the model showed suitable perform, considering the modeling difficult.
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16

Su, Lishan. "Impacts of mass media coverage of the economy during normal times and recessions on the Index of Consumer Confidence using time series analysis and Granger causal analysis /". [Ames, Iowa : Iowa State University], 2008.

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17

Ouldali, Naïm. "Impact à moyen terme de l'implémentation du vaccin conjugué pneumococcique 13 valences en pédiatrie : analyse de séries chronologiques interrompues". Thesis, Université de Paris (2019-....), 2020. https://wo.app.u-paris.fr/cgi-bin/WebObjects/TheseWeb.woa/wa/show?t=4437&f=28972.

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Introduction. Le bénéfice à moyen terme de l’implémentation des vaccins pneumococciques conjugués (VPCs) reste à préciser, du fait du remplacement sérotypique. Nous avons évalué en France, chez l’enfant, l’impact à moyen terme des VPC sur : (i) les méningites à pneumocoque, (ii) les pneumopathies aiguës communautaires (PAC), (iii) la dynamique de résistance aux antibiotiques des sérotypes pneumococciques dans le portage naso-pharyngé. Nous avons également évalué la qualité méthodologique de la littérature concernant l’impact des VPCs sur les infections pneumococciques. Méthodes. Nous avons exploité les données de 3 observatoires pédiatriques établis à l’échelle nationale : l’observatoire des méningites bactériennes de l’enfant (227 centres), l’observatoire des PAC (8 centres) et l’observatoire du portage pneumococcique (121 pédiatres de ville). Une analyse de séries chronologiques interrompues (SCI), promue par la Cochrane à la place des études avant-après, a été conduite, prenant en compte la tendance temporelle, la saisonnalité et l’autocorrélation des données, via des modèles de régression linéaire segmentée avec erreur auto-corrélée. Enfin, une revue systématique méthodologique a été conduite en incluant toutes les études évaluant l’impact des VPC sur les principales formes d’infections à pneumocoque à la fois chez l’enfant et l’adulte, via PubMed, Embase et les références des articles sélectionnés.Résultats. Après une baisse de l’incidence des méningites à pneumocoque de 38% (IC 95% [20 ; 56]) suite à l’implémentation du VPC13 en France, une remontée a été observée depuis Janvier 2015, principalement liée à l’émergence d’un sérotype non vaccinal. De la même manière, la fréquence des CAP a baissé de 44% (IC 95% [32 ; 56]) après l’implémentation du VPC13, mais depuis Juin 2014 seule une très modeste remontée a été observée. Pour le niveau de résistance des sérotypes pneumococciques, après une baisse notable suite au VPC13, une remontée progressive et constante est observée depuis Janvier 2014. Enfin, la revue systématique de la littérature a permis de sélectionner 377 études entre 2001 et 2018. Ces études utilisaient le design avant-après dans 78.5% des cas (N=296) contre 18.3% pour les SCI (N=69).Conclusion. L’impact à moyen terme des VPCs et les conséquences du remplacement sérotypique varient selon les pathologies pneumococciques. Ces résultats sont susceptibles d’évoluer dans les années à venir, nécessitant une surveillance continue. L’utilisation d’outils méthodologiques validés tels que les SCI reste minoritaire à ce jour, et doit être développée pour apprécier la complexité de l’évolution épidémiologique des infections pneumococciques au cours du temps
Background. Due to serotype replacement, the long-term impact of pneumococcal conjugate vaccines (PCVs) implementation remains to be evaluated. We aimed to assess, in children, the impact of PCV13 implementation on: (i) pneumococcal meningitis, (ii) community acquired pneumonia (CAP), and (iii) antibiotic susceptibility of pneumococcal strains in nasopharyngeal carriage. Finally, we conducted a methodological systematic review of the literature on assessing the impact of PCVs implementation. Methods. We used the quasi-experimental interrupted time series (ITS) analysis design with data from three French surveillance systems: (i) the national network of pediatric bacterial meningitis (230 centres), (ii) the CAP pediatric network (8 pediatric emergency departments), and (iii) an ambulatory network of pneumococcal carriage (121 pediatricians). A segmented regression model with autoregressive error was used, taking into account pre-intervention time trend, seasonality and autocorrelation. The methodological systematic review included all studies assessing the impact of PCVs implementation in children and adults, using PubMed, Embase, and references of selected articles. Results. After a 38% (95% CI [20; 56]) decrease of pneumococcal meningitis incidence following PCV13 implementation in 2010 in France, a rebound was observed since January 2015, mainly linked to the emergence of non-PCV13 serotypes. CAP rate also decreased significantly following PCV13 implementation (44% decrease, 95% CI [32; 56]), but since June 2014, only a slight increase was observed since June 2014. Regarding pneumococcal susceptibility in carriage, after a significant reduction of penicillin non-susceptibility following PCV13 implementation, a steady increase is observed since January 2014. Finally, 377 studies were included in the systematic review, from 2001 to 2018. Among them, 296 (78,5%) used the before-after design, and only 69 (18,3%) used the ITS design. Conclusions. After an important impact of PCV13, the consequences of serotype replacement in France may vary between pneumococcal disease. These findings may still evolve in the coming years, underlining the need of continuous active surveillance of these outcomes. Despite Cochrane recommendations, the use of ITS to assess PCVs impact remains largely infrequent worldwide, and needs to be promoted to adequately analyze the complex evolution of this pathogen over time
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18

Rodrigues, Ana Carolina de Mello Alves 1985. "Análise do desempenho muscular do quadríceps e dos isquiotibiais em função da série temporal e da amplitude de movimento de atletas amadoras de futsal feminino = Analysis of muscle performance of the quadriceps and hamstrings as a function of the times series and range of motion of amateurfemale futsal athletes". [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/275093.

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Orientador: Sérgio Augusto Cunha
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação Física
Made available in DSpace on 2018-08-22T12:25:32Z (GMT). No. of bitstreams: 1 Rodrigues_AnaCarolinadeMelloAlves_M.pdf: 2144136 bytes, checksum: d441e8c33daa046aa1f2cfd67d18b720 (MD5) Previous issue date: 2013
Resumo: A análise do desempenho muscular por dinamometria hipocinética comumente utiliza-se de valores de torque máximo de quadríceps e isquiotibiais. Porém com a utilização dos valores de torque em função da amplitude de movimento, bem como o cálculo da potência e do desequilíbrio muscular desta maneira torna possível observar o comportamento muscular e a capacidade de estabilização do joelho ao longo de toda amplitude de movimento, e possibilita identificar amplitudes que há risco de lesão de LCA. O objetivo deste estudo foi analisar a série temporal da produção de torque do quadríceps e dos isquiotibiais e calcular a potência e o desequilíbrio muscular de atletas de futsal feminino em função do ciclo de movimento de flexão e extensão do joelho no membro dominante. A amostra foi composta de 19 atletas amadoras de futsal feminino, com idade média de 20 ± 2,83 anos. A avaliação consistiu em 2 série de 5 repetições máximas de extensão/flexão do joelho unilateral de forma concêntrica, em 2 velocidades angulares (180°·s-1 e 210°·s-1) através de um dinamômetro isocinético (Biodex System Pro4). As análises foram baseadas nos valores de torque e potencia do quadríceps e dos isquiotibiais em função da amplitude de movimento, e foram calculadas a razão entre essas musculaturas em função da amplitude de movimento. Foram comparados os valores de torque, potência e razão em função do ângulo do joelho, para ambas as velocidades através da ANOVA e teste de Tukey post hoc. As variáveis foram analisadas em rotinas de ambiente Matlab®, com o valor de significância de 5%. Os valores de torque e potencia do quadríceps apresentaram-se maiores de 40% a 80% do ciclo de movimento nas velocidades de 180°·s-1 e 210°·s-1 que corresponde aos ângulos de 50° a 70° de flexão do joelho. Os valores do torque dos isquiotibiais foram maiores de 80% a 100 % do ciclo, que corresponde aos ângulos de 70° a 80° de flexão do joelho em ambas as velocidades, enquanto que a potencia dos isquiotibiais foi constate até 70% do ciclo, com menores valores de 70% a 100% do ciclo, que corresponde aos ângulos de 65° a 80° de flexão do joelho. Com relação a razão em função do ciclo de movimento, 6 atletas apresentaram em algum instante do ciclo de movimento valores abaixo de 60% na velocidade de 180°·s-1, e 4 atletas a 210°·s-1. O estudo mostra que análise do torque, potência e razão ao longo do ciclo de movimento caracteriza melhor o desempenho muscular destas atletas e identifica desequilíbrios entre isquiotibiais e quadríceps que poderiam não ser encontrados com o método de análise convencional, além de fornecer informações sobre desempenho em ângulos específicos do movimento de flexão e extensão do joelho que podem ser utilizados no treinamento e reabilitação destes grupos musculares
Abstract: The analysis of the muscle performance by isokinetic dynamometry is commonly used by peak torque of quadriceps and hamstrings. However, with the use of the torque values as a function of the amplitude of motion, as well as the calculation of the power and muscle imbalance in this way makes it possible to observe the behavior and the ability muscular stabilization of the knee over the entire range of motion, and helps identify amplitudes there is risk of ACL injury. The aim of this study was to analyze the time series of the torque production of the quadriceps and hamstrings and calculate power and muscle imbalance of female soccer athletes due to the cycle of movement of flexion and knee extension limb dominant. The sample consisted of 19 athletes amateur futsal, mean age 20 ± 2.83 years. The evaluation consisted of two series of five repetitions maximum extension / flexion of the knee-sided concentrically in two angular velocities (180°·s-1 e 210°·s-1) using an isokinetic dynamometer (Biodex System Pro4) . The analyzes were based on the values of torque and power of the quadriceps and hamstrings due to the range of motion, and we calculated the ratio of these muscles due to the range of motion. We compared the values of torque, power and reason as a function of knee angle for both speeds by ANOVA and Tukey post hoc. The variables were analyzed in Matlab ® routines, with the significance level of 5%. The values of torque and power of the quadriceps were higher than 40% to 80% of the cycle of motion at speeds of 180°·s-1 and 210°·s-1 which corresponds to angles of 50° to 70 ° of flexion knee. The hamstring torque values were greater than 80% to 100% duty cycle, corresponding to angles of 70° to 80° of knee flexion at both speeds, whereas the power hamstring muscles were finds up to 70% of the cycle, lower ratios of 70% to 100% duty cycle, corresponding to angles of 65° to 80° of knee flexion. Regarding the ratio as a function of the movement cycle 6 athletes had at some point in the movement cycle values below 60% at a rate of 180°·s-1 and athletes 4 at 210°·s-1. The study shows that analysis of the torque, power and reason throughout the movement cycle is a better muscle performance of athletes identifies imbalances between hamstring and quadriceps that could not be found with the conventional method of analysis, in addition to providing information about performance specific angles of flexion and extension of the knee that can be used in the training and rehabilitation of such muscle groups
Mestrado
Biodinamica do Movimento e Esporte
Mestra em Educação Física
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19

Mei, Jiali. "Time series recovery and prediction with regression-enhanced nonnegative matrix factorization applied to electricity consumption". Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS578/document.

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Nous sommes intéressé par la reconstitution et la prédiction des séries temporelles multivariées à partir des données partiellement observées et/ou agrégées.La motivation du problème vient des applications dans la gestion du réseau électrique.Nous envisageons des outils capables de résoudre le problème d'estimation de plusieurs domaines.Après investiguer le krigeage, qui est une méthode de la litérature de la statistique spatio-temporelle, et une méthode hybride basée sur le clustering des individus, nous proposons un cadre général de reconstitution et de prédiction basé sur la factorisation de matrice nonnégative.Ce cadre prend en compte de manière intrinsèque la corrélation entre les séries temporelles pour réduire drastiquement la dimension de l'espace de paramètres.Une fois que le problématique est formalisé dans ce cadre, nous proposons deux extensions par rapport à l'approche standard.La première extension prend en compte l'autocorrélation temporelle des individus.Cette information supplémentaire permet d'améliorer la précision de la reconstitution.La deuxième extension ajoute une composante de régression dans la factorisation de matrice nonnégative.Celle-ci nous permet d'utiliser dans l'estimation du modèle des variables exogènes liées avec la consommation électrique, ainsi de produire des facteurs plus interprétatbles, et aussi améliorer la reconstitution.De plus, cette méthod nous donne la possibilité d'utiliser la factorisation de matrice nonnégative pour produire des prédictions.Sur le côté théorique, nous nous intéressons à l'identifiabilité du modèle, ainsi qu'à la propriété de la convergence des algorithmes que nous proposons.La performance des méthodes proposées en reconstitution et en prédiction est testé sur plusieurs jeux de données de consommation électrique à niveaux d'agrégation différents
We are interested in the recovery and prediction of multiple time series from partially observed and/or aggregate data.Motivated by applications in electricity network management, we investigate tools from multiple fields that are able to deal with such data issues.After examining kriging from spatio-temporal statistics and a hybrid method based on the clustering of individuals, we propose a general framework based on nonnegative matrix factorization.This frameworks takes advantage of the intrisic correlation between the multivariate time series to greatly reduce the dimension of the parameter space.Once the estimation problem is formalized in the nonnegative matrix factorization framework, two extensions are proposed to improve the standard approach.The first extension takes into account the individual temporal autocorrelation of each of the time series.This increases the precision of the time series recovery.The second extension adds a regression layer into nonnegative matrix factorization.This allows exogenous variables that are known to be linked with electricity consumption to be used in estimation, hence makes the factors obtained by the method to be more interpretable, and also increases the recovery precision.Moreover, this method makes the method applicable to prediction.We produce a theoretical analysis on the framework which concerns the identifiability of the model and the convergence of the algorithms that are proposed.The performance of proposed methods to recover and forecast time series is tested on several multivariate electricity consumption datasets at different aggregation level
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Wang, Wen-Tien. "Case Study: Future Scenarios of Japan’s Energy Supply System in the Aftermath of the Fukushima Daiichi Nuclear Power Disaster". Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-412800.

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Nine years have passed since the Fukushima Daiichi nuclear disaster (FDND). The Japanese government has been facing the issue of striking a balance among economy, environment, and social opinions for its energy transition policy. Increasing usages of fossil fuel, natural gas, and coal can fix the energy gap left out by reduced nuclear use and stabilise Japan’s energy supply, ensuring economic growth; however, the measure would increase the global warming potential. This study applies the Fossil fuel supply security index (FFSSI) to quantify the present energy supply security in Japan and presents future scenarios of greenhouse gas emissions (GHGs) based on analysed results from the Linear Regression, Polynomial Regression, and Holt-Winters forecasting models. The driving forces of GHGs are analysed by Kaya identity to show the outlook in Japan. The aim of this study is to present the feasibility of reaching the Japanese government launched “Long-Term Energy Supply and Demand Outlook” for fiscal 2030, under Japan’s current energy supply system for policymaker’s consideration. Compared with other Asian-pacific countries (China, South Korea, Taiwan, etc.), the lacking self- sufficiency energy is the major weakness for Japan’s present energy supply system. Moreover, extrapolations based on several forecasting models indicate that the carbon dioxide emission is expected to increase in the next decade if keep continuing the present structure of the energy supply system.
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21

Stephan, Gaëtan. "La déformation de la loi d'Okun au cours du cycle économique". Thesis, Rennes 1, 2014. http://www.theses.fr/2014REN1G043/document.

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Cette thèse met en évidence l'aspect asymétrique de l'élasticité du chômage par rapport à la production aux Etats-Unis et en Europe. Une première partie de ce travail empirique revient sur une estimation de la valeur ``authentique'' du coefficient d'Okun corrigé du biais de publication. Nous employons une méta-analyse et nous montrons qu'un aspect important de déformation du coefficient réside dans le choix de la variable endogène. Dans le second chapitre, nous montrons que loi d'Okun implique dans ses fondements un comportement procyclique de la productivité générée par la pratique de la rétention de main d’œuvre. L'économie américaine présente une déformation significative du coefficient d’Okun au cours des récessions et reprises depuis le milieu des années 80, quand la productivité a perdu son caractère procyclique. En Allemagne et en France, à l’inverse, le coefficient d'Okun se déforme peu au cours du cycle. Cette spécificité européenne pourrait venir de la nature des fluctuations macroéconomiques. Ainsi, l'économie allemande enregistre des chocs macroéconomiques avec un fort caractère transitoire et persistant. Néanmoins, le reste des pays européens présentent des chocs de nature permanente. Dans le dernier chapitre, nous montrons que le PIB réel et le chômage peuvent partager une relation de cointégration asymétrique qui semble être associée à une courbe de Phillips asymétrique
This dissertation aims at study asymmetry of elasticity of unemployment to output in United States and Europe. In the first chapter, we employ a meta-analysis to identify the ``authentic'' value of Okun's law coefficient beyond publication bias. We show that measure of Okun's coefficient depends about the choice of endogenous variable. In the second chapter, it appears that Okun's law implies a labor productivity procyclical as firm practices labor hoarding. According our estimates, Okun's law presents significative evidence of asymmetry during recessions and recoveries especially since the mid-1980s when positive correlation between real GDP and productivity has disappeared. Conversely, in France and Germany, we observe a more stable Okun's coefficient along business cycle. The nature of macroeconomic movements in Europe could potentially explain these findings. Germany supports transitory and persistent movements in real GDP and unemployment. Nevertheless, macroeconomic movements in other European countries are driven by permanents shocks. In last chapter, we investigate asymmetric cointregration in a sample of European countries (France, Germany and United Kingdom), we show that asymmetric cointegration between real GDP and unemployment seems to be linked to an asymmetric Phillip's curve
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22

Einarsson, Sigurdur. "Analysis of a Flexible Small-Series Flow Line for Prototype Production of Cutting Inserts : A study carried out at Sandvik Coromant in Gimo in order to evaluate how a new flexibleflow line can be planned in order to meet requirements of short lead times andhigh service level". Thesis, KTH, Industriell produktion, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-151254.

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In the modern manufacturing industry the need for faster and more robust product development processes is seen as one of the main strategic areas to focus on in order to support sustainable growth and even long term survival of companies due to continuously increasing global competition. For the metal-cutting tool manufacturer Sandvik Coromant product development is seen as a key strategic area and due to that improvements in the overall product development chain are being worked on. In order to have more reliable production of prototypes and at the same time have them delivered within short and predictable lead time a new small-series flexible manufacturing line needs to be set up. This project takes on analysis of three levels of analysis for this new manufacturing line, that is production planning, flow analysis and scenario analysis. Through the analysis information has been collected to set up the boundaries for which the system needs to work within, such as demand forecast, processing requirements and planning as well as estimation of cycle times for different steps in the flow. The project provider had already made a framework of manufacturing techniques and concepts which are known but the idea for this project was to put those pieces together in a system model which could be analysed with regards to flow characteristics and system performance. The results would then be a basis for a decision on capacity and layout design for the new system. It is shown that the decision on capacity is mostly related to resource planning at the system bottleneck, which is a precision material removal station applying either high-speed milling or laser technology for material removal. Scenarios for variables such as order batch sizes are analysed and it is shown how the target for service level can be reached by for example increasing lead time definition for large order batches. For a higher capacity option at the bottleneck operation the robustness of the system is tested by adjusting demand and cycle time needs for the bottleneck step, and this gives results within service level target for those scenarios. The idea is that all machining operations and key measurements for the products should be possible to do within the flow line. This results in relatively low utilization for some of the equipment, but this is a trade-off which makes the system flexible and independent. The effect of having a transportation robot for the flow line is checked as an alternative to having operator at the line 16 hours per day. In the base case with the operators, automatic pallet exchange functionality is set up at the two most utilized machines with local pallet magazine for parts to be manufactured. It is shown that a solution with a transportation robot would only result in about 1% higher serve level compared to the base case solution. It was a conclusion to recommend a solution with only one machine for the bottleneck operation and either add restriction on order batch sizes or define longer lead time for larger order batches. It was recommended to implement pallet exchanger with a local pallet magazine for pallets which hold the parts at two work stations which have the highest utilization. This solution would according to the given background information and input variables give a desired service level by operating with one operator 16 hours per day, 7 days a week, and unmanned night shifts for which the high utilization machines could be unloaded and loaded by an automated pallet exchanger and thus could operate automatically during night time.
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Baptista, Margarete ártico. "Gráficos de recorrência e de poincaré na análise da quantidade de internações por diferentes grupos nosológicos, ocorridas ao longo de uma década, em um hospital de ensino". Faculdade de Medicina de São José do Rio Preto, 2011. http://bdtd.famerp.br/handle/tede/101.

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Made available in DSpace on 2016-01-26T12:51:30Z (GMT). No. of bitstreams: 1 margaretearticobaptista_tese.pdf: 3014770 bytes, checksum: a4b4de19204259991aae1ec3ae61a0aa (MD5) Previous issue date: 2011-10-07
In the last 30 years, the increasing health care expenditures resulted in an outburst of studies aimed at new proposals on the methodological evaluation of health services. With the aid of computing, several studies have been developed with the purpose of analyzing nonlinear and complex systems. The most outstanding among those methods was the Recurrence Plot, first described by Erickman et al. (1987).Objectives: To analyze the temporal behavior of the weekly amount of admissions by some nosologic groups (Appendix Diseases, Bacterial Diseases, Neoplastic Disease, and Acute Coronary Syndrome), which has occurred over a decade, through Recurrence Plots and Poincaré Recurrence Plots, as well as checking whether the systems are presenting a periodic, chaotic, or random behavior pattern. Material and Methods: The database containing all hospitalizations recorded at the Hospital de Base Regional Medical School Foundation (FUNFARME) of Sao Jose do Rio Preto, a teaching hospital, from January 1, 1998 to December 31, 2007 was peered into a microscope. As a reference to classify all these admissions, the International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10) was used. The Microsoft Office Excel 2003® was the software used to arrange the data into columns. The admissions were systematically set to the right array, such as day, month, and year. They were arranged into columns according to the uniform criteria of identification of the epidemiological weeks. The recurrence graphs and the respective quantitative analyses of recurrence were developed with the aid of the Visual Recurrence Analysis (VRA) software, which is freely available on the Internet. To perform the comparison among the behavior patterns, mathematical models of time series for random behavior pattern, series time for chaotic behavior pattern, series times for periodic behavior pattern, and series time for linear behavior pattern were constructed. And it has also been performed a comparison between the Recurrence Plots and the Quantitative Analysis of Recurrence with clinical cases of specific groups (young, adult, child, premature newborn, and brain death).Results: It has become clear that the number of weekly admissions for diseases of the appendix has had a tendency over the years from a random behavior pattern. In hospitalizations due to bacterial diseases, there was a chaotic behavior pattern and the neoplastic diseases showed a chaotic behavior pattern tending to a linear behavior pattern. Hospitalizations because of Acute Coronary Syndrome presented a predominantly linear behavior pattern. Conclusions: The visual aspects of Recurrence Plot and Poincaré Recurrence plot exhibited different patterns when comparing quantities of admissions of certain nosologic groups over a decade. The quantitative analysis of recurrence that was useful in classifying the behavior pattern of the quantities of admissions is likely to constitute a useful tool of evaluation and decision making regarding hospital administration.
Nos últimos trinta anos, o crescimento dos gastos com a atenção médica resultou numa expansão dos estudos voltados para novas propostas metodológicas sobre avaliação dos serviços de saúde. Com a utilização da informática, vários estudos têm sido desenvolvidos para análise de sistemas complexos e não lineares, destacando-se, entre esses métodos, os gráficos de recorrência, descritos pela primeira vez por Erickman et al. (1987). Objetivos: Analisar o comportamento temporal da quantidade semanal de internações por alguns grupos nosológicos (Doenças do Apêndice, Doenças Bacterianas, Doenças Neoplásicas e por Síndrome Coronária Aguda) ocorridas ao longo de uma década, por meio de Gráficos de Recorrência e Gráficos de Poincaré e verificar se são sistemas que apresentam comportamentos periódicos, aleatórios ou caóticos. Material e Método: Foi avaliado o banco de dados contendo todas as internações no Hospital de Base da Fundação Faculdade Regional de Medicina de São José do Rio Preto, no período de 01 de janeiro de 1998 a 31 de dezembro de 2007. Como referência para classificação dessas internações, utilizou-se a Décima Revisão da Classificação Internacional de Doenças e de Problemas Relacionados à Saúde (CID 10). Foi utilizado o programa Microsoft Office Excel 2003 para a tabulação dos dados. As internações foram ordenadas em dia, mês, ano e tabuladas, seguindo o critério uniforme de identificação das semanas epidemiológicas. Os gráficos de recorrência e respectiva análise quantitativa foram construídos com o auxílio do software Visual Recurrence Analysis (VRA), disponível gratuitamente na Internet. Para realizar a comparação de padrões de comportamentos foram construídos modelos matemáticos de séries temporais aleatória, caótica, periódica e linear. E também foi realizada comparação entre Gráficos de Recorrência e Análise Quantitativa da Recorrência com casos clínicos de grupos específicos (jovem adulto, criança, Recém- nascido prematuro e morte cerebral). Resultados: Evidenciou-se que a quantidade de internações semanal por doenças do apêndice tiveram uma tendência ao longo dos anos de comportamento aleatório. Nas internações por doenças bacterianas houve comportamento caótico e as internações por doenças neoplásicas apresentaram um comportamento caótico tendendo a linear. As internações por Síndrome Coronária Aguda apresentaram predominantemente comportamento linear, Conclusões: Os aspectos visuais dos Gráficos de Recorrência e de Poincaré exibiram padrões diferentes na comparação entre quantidades de internações de determinados grupos nosológicos ao longo de uma década. A análise quantitativa da recorrência que auxiliou na classificação do comportamento das quantidades de internações e pode constituir-se em ferramenta útil de avaliação e tomada de decisão em administração hospitalar.
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Silveira, Vinicius Girardi da. "Uma nova forma de medir liquidez: construção e aplicação no mercado brasileiro". Universidade Federal de Santa Maria, 2017. http://repositorio.ufsm.br/handle/1/12331.

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This study aimed to construct a liquidity measure using their proxies and assess their applicability in the financial context. To that, this study proposes the creation of a negotiability measure, which is a compendium of negotiability proxies used by the literature. The statistical procedure used to obtain this measure was the time series factor analysis (TSFA), which it is an extension of traditional factor analysis, working with time series instead of cross-section data. The data used for the illustration presented came from the trading of 858 stocks on BM&FBOVESPA from January 2000 to February 2016. As a result, the measure constructed for the market was demonstrated to be consistent with the others and capable, in terms of correlation, of replacing the proxies used in its construction. In addition, it presented intermediate statistics in relation to their peers, which suggests that the measure can show more balanced results. When analyzed the applicability of the measure in liquidity pricing models, was observed that it has an explanatory power similar to the other proxies used. Having as main differential the advantage of reducing the dimensions of liquidity, considering the information contained in all proxies in only one measure. Moreover, the findings suggest no differences between the means of the measures. However, when observed the variance, the negotiability measure showed distinct from the others, presenting intermediate statistics. In this sense, it is possible to conjecture that the negotiability measure tends to present similar results when used in models based on average, as is the case of regressions. On the other hand, it may be more advantageous and accurate in models that consider variance.
O presente estudo teve o objetivo de construir uma medida de liquidez utilizando suas proxies e avaliar a sua aplicabilidade no contexto financeiro. Para tanto, este trabalho propôs a criação de uma medida de negociabilidade, a qual é um compendio de proxies de negociabilidade empregadas pela literatura. O procedimento estatístico utilizado para a obtenção desta medida foi a Análise Fatorial de Séries Temporais (TSFA), a qual é uma extensão da análise fatorial tradicional, trabalhando com séries de tempo ao invés de dados de corte. Os dados utilizados para a ilustração apresentada foram provenientes da negociação de 858 ações na BM&FBOVESPA no período de janeiro de 2000 até fevereiro de 2016. Como resultados, a medida construída para o mercado demonstrou-se consistente em relação às demais e capaz, em termos de correlação, de substituir as proxies utilizadas na sua construção. Além disso, apresentou estatísticas intermediárias em relação aos seus pares, o que sugere que a medida pode exibir resultados mais equilibrados. Quando analisada a aplicabilidade da medida em modelos de precificação com liquidez, observou-se que ela possui um poder explicativo similar as outras proxies utilizadas. Tem como principal diferencial a vantagem de reduzir as dimensões da liquidez, pois considera a informação contida em todas as proxies em apenas uma medida. Além disso, as descobertas sugeriram não haver diferenças de médias entre as medidas. Porém, quando observada a variância, a medida de negociabilidade se mostrou distinta das demais, apresentando estatísticas intermediárias. Neste sentido, é possível conjecturar que a medida de negociabilidade tende a apresentar resultados similares quando utilizada em modelos baseados em média, como é o caso das regressões. Por outro lado, pode ser mais vantajosa e precisa em modelos que considerem a variância.
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25

Rose, Alyssa. "Intensive narrative intervention with four inner-city children: An interrupted time series analysis". Master's thesis, 2009. http://hdl.handle.net/10048/847.

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This study investigated the effect of a two week intensive narrative intervention program on the narrative abilities of four inner-city children, using an interrupted time-series with removed treatment design. The intervention program focused on teaching five specific story grammar units. The variables of interest in this study were: improvement in story macrostructure, microstructure and language quantity, as well as improvement of scores on standardized narrative tools. All participants showed an improvement in at least one of the narrative skills examined in this study; one of four participants showed an improvement in all of the narrative skills examined in the study. The results of this study indicate that intensive narrative intervention is a viable treatment approach and should be further investigated.
Speech-Language Pathology
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Rose, Alyssa. "Intensive narrative intervention with four inner-city children an interrupted time series analysis /". 2010. http://hdl.handle.net/10048/847.

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Thesis (M.Sc.)--University of Alberta, 2010.
Title from pdf file main screen (viewed on December 8, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science, Speech Pathology and Audiology." At head of title screen : University of Alberta. Includes bibliographical references.
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HUANG, HUI-LIN, e 黃慧鈴. "Does an emergency Pay-For-Performance Program matter? A five-year interrupted time series analysis on inter-hospital transfer". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/ser979.

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碩士
輔仁大學
公共衛生學系碩士班
106
Foreword: Emergencies have created serious public health problems throughout the world. While the number of emergency visits has been increasing year by year, the resources for emergency treatments, including physicians, hospitals, and beds, have shown a downward trend, which bring about two negative effects. 1) Acute and severe diseases may not be treated in a timely manner in a hospital emergency room. 2) For non-emergency and less severe diseases, emergency patients may not be able to stay in hospital wards. This result may cause severe emergency congestion problems, although timely and appropriate referalls may help in the reduction of these two negative effects. Objective:The goal of this study is to see whether Taiwan’s P4P is able to establish a proper referral system for emergency care - that is, whether it can increase the up- and down-breaking of acute and severe illnesses (going to a hospital with a severe acute illness treatment center), or whether it is possible to increase mild rotation (the same grade hospital) or just rotation (go to a hospital without an acute and severe treatment center). This study explores the following questions: 1) Can P4P increase the number of referrals for referral and rotation (including transfer) for all prescribed diseases? 2) Can P4P increase the number of referral cases for individually prescribed diseases? 3) Can P4P increase the number of people who do not require a referral for individual diseases? Methods:This study employs a retrospective analysis method to collect emergency patient referral medical records (including transfer and transfer) from January 2009 to September 2014 at four hospitals in north Taiwan. Data analysis utilizes three parameters in the basic/uncontrolled mode: pre-intervention trend, intervention point effect, and post-intervention trend. We then add self-variables to control the model and to see if the number of referrals increases for each type of major diagnosis after intervention. Results:The study finds that P4P is able to slightly increase the number of referral patients for the transfer of a disease under regulatory requirements, but does not increase the number of referrals for the transfer of the disease. In terms of individual diseases, the increase in the number of policing is mainly due to pneumonia, chronic renal failure, and congestive heart failure. Although the overall number of patients does not increase, there is a slight increase in the number of patients undergoing aortic dissection. In terms of unspecified diseases, the number of people with abdominal pain significantly drops after P4P implementation, and there is no significant increase in the number of patients with intracerebral hemorrhage. This offers evidence that Taiwan’s emergency P4P program can slightly increase the referral of prescribed diseases. The number of people, especially the number of people who need to turn sick. Conclusion:An emergency P4P combined with a referral network design policy is able to indeed slightly increase the number of patients in an emergency department. However, in the future, non-emphasis patients with an active education should be able to transfer to other hospitals in order to make the acute and severe disease system become more efficient.
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Koehle, Gregory M. "An Interrupted Time Series Analysis of the State College Nuisance Property Ordinance and an Assessment of Rental Property Managers as Place Manager/Intimate Handler of Offender". Thesis, 2011. http://hdl.handle.net/2069/454.

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This research involves a legal impact study of the State College Nuisance Property Ordinance and an assessment of State College Rental Property Managers in the role of place manager/intimate handler of offender. The impact of the Ordinance was assessed by employing an interrupted time series design which examined five years of pre-ordinance violations against five years of post-ordinance violations. The assessment of State College Rental Property Managers in the role of place manager/intimate handlers of offenders was assessed through a mail survey. The survey contained items that measured the level to which State College Rental Property Managers have assumed this role. This level was then regressed against the offenses covered under the Ordinance in order to determine if this role has an impact on reducing and/or deterring offenses in rental units. The data suggest that the Ordinance was successful in reducing violations in nuisance rental units. In addition, the analyses of the survey revealed that a higher level of place manager/intimate handler of offender was positively correlated with criminal and ordinance violations.
Dr. Randy L. Martin Dr. Kathleen J. Hanrahan Dr. Jennifer J. Roberts Dr. John A. Lewis
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Linteau, Isabelle. "Analyse des bornes extrêmes et le contrôle des armes à feu : l’effet de la Loi C-68 sur les homicides au Québec". Thèse, 2010. http://hdl.handle.net/1866/4754.

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Contexte et objectifs. En 1995, le gouvernement canadien a promulgué la Loi C-68, rendant ainsi obligatoire l’enregistrement de toutes les armes à feu et affermissant les vérifications auprès des futurs propriétaires. Faute de preuves scientifiques crédibles, le potentiel de cette loi à prévenir les homicides est présentement remis en question. Tout en surmontant les biais potentiels retrouvés dans les évaluations antérieures, l’objectif de ce mémoire est d’évaluer l’effet de la Loi C-68 sur les homicides au Québec entre 1974 et 2006. Méthodologie. L’effet de la Loi C-68 est évalué à l’aide d’une analyse des bornes extrêmes. Les effets immédiats et graduels de la Loi sont évalués à l’aide de 372 équations. Brièvement, il s’agit d’analyses de séries chronologiques interrompues où toutes les combinaisons de variables indépendantes sont envisagées afin d’éviter les biais relatifs à une spécification arbitraire des modèles. Résultats. L’introduction de la Loi C-68 est associée à une baisse graduelle des homicides commis à l’aide d’armes longues (carabines et fusils de chasse), sans qu’aucun déplacement tactique ne soit observé. Les homicides commis par des armes à feu à autorisation restreinte ou prohibées semblent influencés par des facteurs différents. Conclusion. Les résultats suggèrent que le contrôle des armes à feu est une mesure efficace pour prévenir les homicides. L’absence de déplacement tactique suggère également que l’arme à feu constitue un important facilitateur et que les homicides ne sont pas tous prémédités. D’autres études sont toutefois nécessaires pour clairement identifier les mécanismes de la Loi responsables de la baisse des homicides.
Context and objectives. Laws with extensive background checks and making mandatory the registration of all guns have been adopted by some governments to prevent firearms-related homicides. On the other hand, methodological flaws found in previous evaluations question the potential of such laws to prevent gun homicides. By taking into account previous limitations, the main objective of this study is to estimate the effect of Bill C-68 on homicides committed in the Province of Quebec, Canada, between 1974 and 2006. Methodology. Using extreme bounds analysis, we assess the effect of Bill C-68 on homicides. Estimates of the immediate and gradual effects of the law are based on a total of 372 equations. More precisely, interrupted time series analyses were conducted, using all possible variable combinations, in order to overcome biases related to model specification. Results. We found that Bill C-68 is associated with a significant and gradual decline in homicides committed with a long gun (either a riffle or a shotgun). The substitution effects are not robust with respect to different model specifications. Patterns observed in homicides involving restricted or prohibited firearms suggest that they are influenced by different factors, not considered in our analyses. Conclusion. Results suggest that enhanced firearm control laws are an effective tool to prevent homicides. The lack of tactical displacement supports the concept of firearm as a crime facilitator and suggests that all homicides are not carefully planned. Other studies are however needed to pinpoint law provisions accountable for the decrease in homicides.
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Rocha, Teresa Raquel Corga Teixeira da. "Similarity Based Approaches for the Analysis and Prediction of Physiologic Times Series". Doctoral thesis, 2013. http://hdl.handle.net/10316/23380.

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Tese de doutoramento em em Engenharia Informática, apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra.
Cardiovascular disease (CVD), a general name for a wide diversity of diseases, disorders and conditions that affect the heart and often the blood vessels, is the largest cause of death in the European Union. Since it is well known that heart health is linked to behaviour and lifestyle, the focus should be on prevention. In the context of preventive medicine, telemonitoring solutions are making a huge impact by enabling remote patient monitoring for the healthy and for those requiring management of chronic diseases. One of the projects that address CVDs management by means of telemonitoring is HeartCycle, a European Integrated Project (FP7-216695) that aims at researching, developing and clinically validating innovative solutions for this purpose. Particularly, the goal of HeartCycle is to improve the quality of care for coronary artery disease (CAD) and heart failure (HF) patients. Integrated in the third workpackage (WP3-Multi-parametric Analysis and Decision Support), the present thesis is centred on the development of specific clinical applications, which target cardiovascular conditions identified as relevant for the CAD/HF management, such as ischemia, arrhythmias and hypertension, based on the analysis and processing of the electrocardiogram (ECG) and blood pressure (BP) signals daily collected by home telemonitoring. Namely, investigation is made on techniques for the diagnosis of the referred conditions, and for the analysis of future trends of these signals enabling the early detection of critical events. Specifically, this thesis presents methodologies for similarity detection and prediction in biosignal time series, which are mainly founded on the representation of signals as linear combinations of a set of orthogonal basis and on the time-frequency analysis of those signals. Particularly, it proposes a new strategy for diagnosing ischemia comprising a measure for evaluating the ST deviation based on the time-frequency analysis of the ECG through the Wigner-Ville transform, and the use of Hermite basis functions to capture the most relevant morphologic characteristics of the QRS complex. This methodology was tested using the European Society of Cardiology ST-T public database, and the relevant results achieved, namely a sensitivity of 96.7% and a positive predictivity of 96.2%, confirmed its potential. Additionally, a new similarity measure based on a combination of the wavelet transform with the Karhunen-Loève transform for temporal patterns detection in biosignal time series, mainly to support prediction methodologies, was developed. The respective validation was performed by quantitatively comparing the proposed measure with other three common measures through the use of data from a public dataset of Physionet (MIMIC-II) and from a private telemonitoring platform (TEN-HMS). The obtained results confirm that the proposed similarity is particularly appropriate to deal with noise, trends and signals that are not perfectly aligned in time. Moreover, an iterative implementation allows for its efficient computational implementation. In terms of predictive strategies two approaches are explored. The first, based on generalized regression neural networks integrated into a multi-model structure is designed for the accurate prediction of time series future values. It was applied in the prediction of acute hypotensive episodes (AHE) and validated in the context of the 2009 Physionet/Computers in Cardiology Challenge using data from MIMIC-II dataset. A correct prediction of 10 out of 10 AHE for test set A and of 37 out of 40 AHE for test set B was achieved, corresponding to the best results of all entries in the two events of the challenge. The main advantage of the second approach is that it does not require the development of a model. It exploits the multi-resolution analysis provided by the wavelet transform to estimate future evolution trend of biosignals, based on the trend evolution of similar historic signals. Its validity was demonstrated by the comparison with other common predictive methodologies. It was employed in the evaluation of the hypertension risk using data from TEN-HMS and MyHeart studies. The obtained results, in terms of Sensitivity-Specificity, were of 84.2%-75.5% and of 85.7%-91.8%, respectively, for the TEN-HMS and the MyHeart datasets, confirming the capability of the approach in this type of application.
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Wolfshagen, Paul-Alexandre. "Prévention, contre-prévention et analyse d’impact : le cas du clonage de carte de débit". Thèse, 2011. http://hdl.handle.net/1866/6308.

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Abstract (sommario):
Contexte et objectifs. Depuis plusieurs années, la criminalité économique génère des coûts économiques et sociaux importants. Plusieurs acteurs, dont les entreprises privées, se sont mobilisés pour lutter contre ce phénomène. La fraude par carte de débit est un crime économique en expansion contre lequel plusieurs organisations ont entrepris des actions. L’objectif de ce mémoire est d’améliorer les connaissances sur les effets des mesures de prévention situationnelle appliquées dans les succursales d’un commerce de détail et leur impact sur le processus décisionnel des délinquants impliquées dans le clonage de cartes de débit. Méthodologie. Les effets des mesures de prévention mises en place sont évalués à l’aide d’analyses de séries chronologiques interrompues. En complément des analyses statistiques, des entrevues et une analyse documentaire sont effectuées. Les entrevues sont réalisées avec des enquêteurs du service de sécurité de l’entreprise de commerce de détail. L’analyse documentaire est basée sur les rapports d’événement ouverts lors des fraudes par carte de débit. Résultats. Les mesures de prévention ont produit différents effets. Selon la mesure, il fut possible de constater soit une hausse ou une baisse dans le nombre de délits commis. Certaines mesures ont, en outre, provoqué un déplacement spatial, un déplacement dans le choix de la cible, un déplacement dans le type de crime commis et, finalement, un déplacement tactique. Conclusion. Les résultats suggèrent que les mesures de prévention adoptées ont empêché la réalisation des délits associés à la fraude par carte de débit. Par contre, la présence de plusieurs formes de déplacement indique que les fraudeurs se sont adaptés aux mesures de prévention. Afin de documenter adéquatement cette forme de crime et les déplacements générés, d’autres études s’avèrent nécessaires.
Context and objectives. Each year, economic crimes generate important economic and social losses. Many enterprises, including private enterprises, collaborated and introduced initiatives in order to combat this criminality. Fraud using automated payment cards is a crime in full expansion against which many organizations have taken actions. The objective of this dissertation is, on one hand, to improve the knowledge on the impact of preventive measures implemented in the branches of a retailer and, on the other hand, to estimate their impact on the criminal decision-making process. Methodology. The effect of preventive measures is assessed through interrupted time series analysis. In addition, members the retailer security staff were interviewed and a review of event reports associated with debit card fraud was performed. Results. The preventive measures were associated to various results. Depending on the preventive measure, one can observe either an increase or a decrease in the number of crimes performed. It is also observed that some measures have resulted in tactical and spatial displacements. Some offenders have also started to commit other types of crimes. Conclusion. The results suggest that the preventive measures implemented had a significant preventive effect on debit card crimes. However, the presence of many types of displacement shows that the offenders have adjusted to those preventive measures. In order to properly document this type of crime and associated displacements, additional studies are necessary.
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Zombré, David. "La gratuité des soins associée à l’amélioration de la qualité des soins est-elle efficace pour maintenir l’utilisation des services à long terme et améliorer la santé infantile au Burkina Faso ?" Thèse, 2019. http://hdl.handle.net/1866/22580.

Testo completo
Abstract (sommario):
Problématique : L’amélioration de l’accessibilité financière aux soins de santé est essentielle pour réduire la morbidité et de la mortalité infantile dans les pays à ressources limitées. Cependant, les preuves disponibles sur la relation entre un accès accru aux soins et l’amélioration la santé infantile, dans le long terme, demeurent insuffisantes et parfois inconnues. Dans le contexte spécifique de la région du Sahel au Burkina Faso où les niveaux élevés de morbidité et de malnutrition coïncident avec un faible recours aux soins, une intervention de santé publique associant la gratuité des soins à l’amélioration de la qualité des soins et à la prise en charge de la malnutrition dans la communauté a été mise en œuvre en septembre 2008. Objectifs : En utilisant des approches statistiques et épidémiologiques appliquées aux données transversales et de séries chronologiques, cette thèse vise à apporter une meilleure compréhension de la façon dont la présence de l’intervention dans les communautés peut augmenter et maintenir l’utilisation des services de santé à long terme et améliorer la santé des enfants de moins de cinq ans. Les objectifs spécifiques sont : 1) évaluer le maintien à long terme des effets de l’intervention sur l’utilisation des services de santé chez les enfants de moins de cinq ans, 2) évaluer l’effet contextuel de l’intervention, quatre ans après le début de sa mise en œuvre, sur la probabilité de survenue d’une maladie et sur la probabilité d’utilisation des services de santé chez les enfants de moins de cinq ans, et 3) évaluer l’effet contextuel de l’intervention, quatre ans après le début de sa mise en œuvre, sur le retard de croissance chez les enfants de moins de cinq ans. Méthodes : Les données proviennent du système national d’information sanitaire, d’une enquête rétrospective sur les services de santé ainsi que d’une enquête de ménages réalisée quatre ans après le début de l’intervention dans 41 villages du district d’intervention et 51 villages du district de comparaison. Nous avons utilisé un plan quasi expérimental à séries temporelles interrompues avec groupe de comparaison pour évaluer les effets immédiats et à long terme de l’intervention sur les taux d’utilisation des services de santé. Ensuite, un plan d’étude transversale post-intervention avec un groupe de comparaison nous a permis d’évaluer l’effet contextuel de l’intervention sur la probabilité de survenue d’une maladie, sur la probabilité d’utilisation des services de santé et sur le retard de croissance chez les enfants de moins de cinq ans. La stratégie analytique a combiné la méthode de pondération par les scores de propension pour équilibrer les covariables entre les deux groupes, la modélisation binomiale négative à effets mixtes, les régressions linéaire et logistique multiniveaux. Résultats : L’intervention de gratuité des soins associée à l’amélioration de la qualité des soins et à la prise en charge de la malnutrition dans la communauté était associée à l’augmentation et au maintien de l’utilisation des services de santé au-delà de quatre ans (ratio des taux d’incidence = 2,33 ; IC 95 % = 1,98 – 2,67). En outre, comparativement aux enfants vivant dans le district de contrôle, la probabilité d’utiliser les services de santé était de 17,2 % plus élevée chez les enfants vivant dans le district d’intervention (IC 95 % = 15,01–26,6) ; et de 20,7 % plus élevée lorsque l’épisode de maladie était sévère (IC 95 % = 9,9–31,5). Ces associations étaient significatives, quels que soient la distance par rapport aux centres de santé et le statut socio-économique du ménage. Par ailleurs, alors que le contexte de résidence expliquait 9,36 % de la variance du retard de croissance (corrélation intraclasse = 9,36 % ; IC 95 % = 6,45–13,38), la présence de l’intervention dans les villages n’explique que 2 % de la variance du retard de croissance. Cependant, nous n’avons pas pu démontrer que la présence de l’intervention dans les communautés était associée à une réduction de la probabilité de survenue d’un épisode de maladie (Différentiel des probabilités = 4.4 ; IC 95% = -1.0 – 9.8), ni à une amélioration significative de l’état nutritionnel des enfants de moins de cinq ans (RC = 1,13 ; IC 95 % = 0,83–1,54). Conclusion : Cette thèse souligne que la gratuité des soins associée à l’amélioration de la qualité des soins et à la prise en charge de la malnutrition dans la communauté est efficace pour augmenter et maintenir l’utilisation des services de santé et réduire les inégalités géographiques de recours aux soins. Cependant, cette intervention n’était pas associée à une amélioration des résultats de santé infantile. Bien que des études longitudinales rigoureuses soient nécessaires pour comprendre pleinement l’influence potentielle de cette intervention sur la morbidité, cette thèse plaide pour la nécessité d’agir simultanément sur les autres déterminants sociaux de la santé et d’intégrer, de manière synergique, des interventions spécifiques à la nutrition pour plus d’impact sur la santé infantile.
Introduction: Improving financial access to health care is believed to be essential for reducing the burden of child morbidity and mortality in resource-limited settings, but the available evidence on the relationship between increased access and health remains scarce and the long-term issues are still unknown. In the specific context of the Sahel region in Burkina Faso where high levels of morbidity and malnutrition coincide with low health care use, a pilot intervention for free health care including quality of care improvement and management of malnutrition at the community level was implemented in September 2008. Objectives: Using statistical and epidemiological approaches applied to cross-sectional and time series data, this thesis aims to provide a better understanding of how the presence of intervention in communities can increase and maintain long-term use of health services and improve the health of children under five years. The specific objectives are: 1) to evaluate the long-term effects of the intervention on the use of health services in children under the age of five, 2) to estimate the contextual effect of intervention on the probability of occurrence of and the likelihood of health services being used by children under five, four years after the start of its implementation, and 3) to evaluate the contextual effect of the intervention on stunting in children under five, four years after the start of its implementation. Methods: The data for the analyses were provided from a variety of sources including the national health information system, a retrospective health services survey, and a household survey conducted four years after the intervention onset in 41 villages in the intervention district and 51 villages in the comparison district. We used a quasi-experimental controlled interrupted time-series design group to analyze the immediate and long-term effects of the intervention on the rate of health services utilization in children under five. Then, a quasi-experimental post-test-only design that included a control group allowed us to evaluate the contextual effect of the intervention on the probability of occurrence of a disease, on the probability of use of health services, and stunting in children under five. The analytic strategy combined the propensity score weighting method to balance the covariates between the two groups, two-level mixed-effects negative binomial, and linear and logistic regression models to account for the hierarchical structure of data. Results: The intervention for free health care including quality of care improvement and management of malnutrition at the community level was associated with an increased and maintained use of health services beyond four years after the onset of intervention (incidence rate ratio = 2.33; 95% CI = 1.98–2.67). In addition, compared to children living in the comparison district, the probability of using health services was 17.2% higher among those living in the intervention district (95% CI = 15.0–26.6); and 20.7% higher when the illness episode was severe (95% CI = 9.9–31.5). These associations were significant regardless of the distance to health centers and the socio-economic status of households. In addition, inequalities in the use of care were less pronounced in the intervention villages compared to those in the control village. Finally, the results also showed that the residence context accounted for 9.36% of the variance in stunting (intra-class correlation = 9.36% ; 95% CI = 6.45–13.38), and only 2% of the variance in stunting was explained by the intervention. However, we could not demonstrate that the intervention in these communities was associated with a reduced probability of an illness occurring (AME=4.4 (95% CI: -1.0 – 9.8), nor with a significant improvement in the nutritional status among children under five (OR = 1.13; 95% CI = 0.83–1.54). Conclusion: This thesis underlines the importance that affordable health care, including quality of care, as well as improving the management of malnutrition at the community level, are effective in increasing and maintaining the use of health services and reduce geographical inequalities in the use of care. However, this intervention was not associated with improved child health outcomes. Although rigorous longitudinal studies are necessary to fully understand the potential influence of this intervention on morbidity, this thesis highlights the need to simultaneously act on other social determinants of health and to synergistically integrate nutrition-specific interventions for greater impact on child health.
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