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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
421

Data Analytics Techniques with Applications to Designing Environmentally ConsciousBuildings

Yadollahi Farsani, Yasmina January 2020 (has links)
No description available.
422

The Landscape of Food and Beverage Advertising to Children and Adolescents on Canadian Television

Pinto, Adena 05 November 2020 (has links)
Background: Canadian youth obesity, and comorbidities, have paralleled trends in consuming nutrient-poor foods marketed by the food industry. In Canada, food marketing is largely self-regulated by the food industry under the Canadian Children’s Food and Beverage Advertising Initiative (CAI). Methods: Public television programming records benchmarked the volume of food advertising targeted to preschoolers, children, adolescents, and adults on Canadian television. Food advertising rates and frequencies were compared by age group, television station, month, food category, and company, using regression modelling, chi-square tests and principal component analysis. Results: Food advertising rates significantly differed by all independent variables. Fast food companies dominated advertising during adolescent-programming while food and beverage manufacturers dominated advertising during programming to all other age groups. CAI signatories contributed more advertising during children’s programming than non-signatories. Conclusion: Failings of self-regulation in limiting food advertising to Canadian youth demonstrate the need for statutory restrictions to rectify youth’s obesogenic media environments and their far-reaching health effects.
423

Implementation of Anomaly Detection on a Time-series Temperature Data set

Novacic, Jelena, Tokhi, Kablai January 2019 (has links)
Aldrig har det varit lika aktuellt med hållbar teknologi som idag. Behovet av bättre miljöpåverkan inom alla områden har snabbt ökat och energikonsumtionen är ett av dem. En enkel lösning för automatisk kontroll av energikonsumtionen i smarta hem är genom mjukvara. Med dagens IoT teknologi och maskinlärningsmodeller utvecklas den mjukvarubaserade hållbara livsstilen allt mer. För att kontrollera ett hushålls energikonsumption måste plötsligt avvikande beteenden detekteras och regleras för att undvika onödig konsumption. Detta examensarbete använder en tidsserie av temperaturdata för att implementera detektering av anomalier. Fyra modeller implementerades och testades; en linjär regressionsmodell, Pandas EWM funktion, en EWMA modell och en PEWMA modell. Varje modell testades genom att använda dataset från nio olika lägenheter, från samma tidsperiod. Därefter bedömdes varje modell med avseende på Precision, Recall och F-measure, men även en ytterligare bedömning gjordes för linjär regression med R^2-score. Resultaten visar att baserat på noggrannheten hos varje modell överträffade PEWMA de övriga modellerna. EWMA modeller var något bättre än den linjära regressionsmodellen, följt av Pandas egna EWM modell. / Today's society has become more aware of its surroundings and the focus has shifted towards green technology. The need for better environmental impact in all areas is rapidly growing and energy consumption is one of them. A simple solution for automatically controlling the energy consumption of smart homes is through software. With today's IoT technology and machine learning models the movement towards software based ecoliving is growing. In order to control the energy consumption of a household, sudden abnormal behavior must be detected and adjusted to avoid unnecessary consumption. This thesis uses a time-series data set of temperature data for implementation of anomaly detection. Four models were implemented and tested; a Linear Regression model, Pandas EWM function, an exponentially weighted moving average (EWMA) model and finally a probabilistic exponentially weighted moving average (PEWMA) model. Each model was tested using data sets from nine different apartments, from the same time period. Then an evaluation of each model was conducted in terms of Precision, Recall and F-measure, as well as an additional evaluation for Linear Regression, using R^2 score. The results of this thesis show that in terms of accuracy, PEWMA outperformed the other models. The EWMA model was slightly better than the Linear Regression model, followed by the Pandas EWM model.
424

House Price Prediction

Aghi, Nawar, Abdulal, Ahmad January 2020 (has links)
This study proposes a performance comparison between machine learning regression algorithms and Artificial Neural Network (ANN). The regression algorithms used in this study are Multiple linear, Least Absolute Selection Operator (Lasso), Ridge, Random Forest. Moreover, this study attempts to analyse the correlation between variables to determine the most important factors that affect house prices in Malmö, Sweden. There are two datasets used in this study which called public and local. They contain house prices from Ames, Iowa, United States and Malmö, Sweden, respectively.The accuracy of the prediction is evaluated by checking the root square and root mean square error scores of the training model. The test is performed after applying the required pre-processing methods and splitting the data into two parts. However, one part will be used in the training and the other in the test phase. We have also presented a binning strategy that improved the accuracy of the models.This thesis attempts to show that Lasso gives the best score among other algorithms when using the public dataset in training. The correlation graphs show the variables' level of dependency. In addition, the empirical results show that crime, deposit, lending, and repo rates influence the house prices negatively. Where inflation, year, and unemployment rate impact the house prices positively.
425

Spatiotemporal Variations in Coexisting Multiple Causes of Death and the Associated Factors

Salawu, Emmanuel Oluwatobi 01 January 2018 (has links)
The study and practice of epidemiology and public health benefit from the use of mortality statistics, such as mortality rates, which are frequently used as key health indicators. Furthermore, multiple causes of death (MCOD) data offer important information that could not possibly be gathered from other mortality data. This study aimed to describe the interrelationships between various causes of death in the United States in order to improve the understanding of the coexistence of MCOD and thereby improve public health and enhance longevity. The social support theory was used as a framework, and multivariate linear regression analyses were conducted to examine the coexistence of MCOD in approximately 80 million death cases across the United States from 1959 to 2005. The findings showed that in the United States, there is a statistically significant relationship between the number of coexisting MCOD, race, education, and the state of residence. Furthermore, age, gender, and marital status statistically influence the average number of coexisting MCOD. The results offer insights into how the number of coexisting MCOD vary across the United States, races, education levels, gender, age, and marital status and lay a foundation for further investigation into what people are dying from. The results have the long-term potential of helping public health practitioners identify individuals or communities that are at higher risks of death from a number of coexisting MCOD such that actions could be taken to lower the risks to improve people's wellbeing, enhance longevity, and contribute to positive social change.
426

Relationships Between Job Satisfaction, Supervisor Support, and Profitability Among Quick Service Industry Employees

Vann, Joseph Carl 01 January 2017 (has links)
Low profit margins threaten the sustainability of quick service restaurants (QSRs). In the United States, low levels of employee job satisfaction and low employee perceptions of supervisor support decrease organizational profitability by as much as $151 million annually, depending on the size and type of organization. Guided by the 2-factor theory of motivation, the purpose of this correlational study was to examine the relationship between employee job satisfaction, employee perceptions of supervisor support, and organizational profitability. A convenience sample of employees from 86 QSR franchise locations in Houston, Texas completed the Job Satisfaction and Perceived Supervisor Support surveys. Multiple linear regression analysis and Bonferroni corrected significance calculation predicted organizational profitability (F(2, 71) = 9.20, p < .001, R2 = .206) and employee job satisfaction (ï?¢ = .577, p = .025). The effect size indicated that the regression model accounted for approximately 21% of the variance in organizational profitability. Employee perceptions of supervisor support (ï?¢ = -.140, p = .580) did not relate to any significant variation in organizational profitability. The findings may be of value to QSR business professionals developing initiatives to improve organizational profitability. Improving employees' perceptions of supervisor support to generate high levels of employee job satisfaction could affect behavioral social change to enhance the health and wellbeing of employees and the wealth and sustainability of QSR franchise locations.
427

Régression linéaire et apprentissage : contributions aux méthodes de régularisation et d’agrégation / Linear regression and learning : contributions to regularization and aggregation methods

Deswarte, Raphaël 27 September 2018 (has links)
Cette thèse aborde le sujet de la régression linéaire dans différents cadres, liés notamment à l’apprentissage. Les deux premiers chapitres présentent le contexte des travaux, leurs apports et les outils mathématiques utilisés. Le troisième chapitre est consacré à la construction d’une fonction de régularisation optimale, permettant par exemple d’améliorer sur le plan théorique la régularisation de l’estimateur LASSO. Le quatrième chapitre présente, dans le domaine de l’optimisation convexe séquentielle, des accélérations d’un algorithme récent et prometteur, MetaGrad, et une conversion d’un cadre dit “séquentiel déterministe" vers un cadre dit “batch stochastique" pour cet algorithme. Le cinquième chapitre s’intéresse à des prévisions successives par intervalles, fondées sur l’agrégation de prédicteurs, sans retour d’expérience intermédiaire ni modélisation stochastique. Enfin, le sixième chapitre applique à un jeu de données pétrolières plusieurs méthodes d’agrégation, aboutissant à des prévisions ponctuelles court-terme et des intervalles de prévision long-terme. / This thesis tackles the topic of linear regression, within several frameworks, mainly linked to statistical learning. The first and second chapters present the context, the results and the mathematical tools of the manuscript. In the third chapter, we provide a way of building an optimal regularization function, improving for instance, in a theoretical way, the LASSO estimator. The fourth chapter presents, in the field of online convex optimization, speed-ups for a recent and promising algorithm, MetaGrad, and shows how to transfer its guarantees from a so-called “online deterministic setting" to a “stochastic batch setting". In the fifth chapter, we introduce a new method to forecast successive intervals by aggregating predictors, without intermediate feedback nor stochastic modeling. The sixth chapter applies several aggregation methods to an oil production dataset, forecasting short-term precise values and long-term intervals.
428

Moderní statistické postupy ve vyhodnocování pevnosti betonu v tlaku v konstrukcích prostřednictvím tvrdoměrných zkoušek / Modern statistical approach in evaluating the compressive strength of concrete in structures using the rebound hammer method

Janka, Marek January 2022 (has links)
This diploma thesis examines various linear regression methods and their use to establish regression relationships between the compressive strength of concrete determined by the indirect method and by the crushing of the specimens in the press. It deals mainly with the uncertainty of values measured by the indirect method, which is neglected by the usually used ordinary least squares regression method. It also deals with the weighted least squares method, suitable for so-called heteroskedastic data. It compares different regression methods on several sets of previously measured data. The final part of the work examines the effect of removing too influential points identified by Cook's distance, which may skew the regression results.
429

Matematický model rozložení tvrdosti na opěrném válci / Mathematical Model of Hardness Distribution inside Backing Roll

Kracík, Adam January 2011 (has links)
The aim of this work is to get the best detailed knowledge about hardness distribution in first 60 mm below the surface of backing roll. To this end, a method for obtaining multi-dimensional polynomial regression was developed and then a computer program for its processing was written.Way of finding suitable regression surfaces and their subsequent interpretation, is a pivotal part of this work.
430

Data Mining the Effects of Storage Conditions, Testing Conditions, and Specimen Properties on Brain Biomechanics

Crawford, Folly Martha Dzan 10 August 2018 (has links)
Traumatic brain injury is highly prevalent in the United States yet there is little understanding of how the brain responds during injurious loading. A confounding problem is that because testing conditions vary between assessment methods, brain biomechanics cannot be fully understood. Data mining techniques were applied to discover how changes in testing conditions affect the mechanical response of the brain. Data were gathered from literature sources and self-organizing maps were used to conduct a sensitivity analysis to rank considered parameters by importance. Fuzzy C-means clustering was applied to find any data patterns. The rankings and clustering for each data set varied, indicating that the strain rate and type of deformation influence the role of these parameters. Multivariate linear regression was applied to develop a model which can predict the mechanical response from different experimental conditions. Prediction of response depended primarily on strain rate, frequency, brain matter composition, and anatomical region.

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