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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.
91

Internet Mathematical Olympiads

Domoshnitsky, Alexander, Yavich, Roman 12 April 2012 (has links)
Modern Internet technologies open new possibilities in a wide spectrum of traditional methods, used in mathematical education. One of the areas, where these technologies can be efficiently used, is an organization of mathematical competitions. Contestants can stay in their schools or universities in different cities and even different countries and try to solve as many mathematical problems as possible and then submit their solutions to organizers through the Internet. Simple Internet technologies supply audio and video connection between participants and organizers in a time of the competitions.
92

Physiological demands of the Absa Cape Epic mountain bike race and predictors of performance

Greeff, Marli 12 1900 (has links)
Thesis (MScSportSc)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The purpose of this qualitative-quantitative study was to describe the exercise intensity and predictors of performance of a multi-stage mountain bike (MTB) race (2014 Absa Cape Epic) lasting 8 days. Twenty-three amateur mountain bikers (age 39 ± 9 years, height 178.8 ± 8.2 cm, body mass 74.7 ± 9.1 kg, VO2max 54 ± 7 ml.kg-1.min-1) who completed the 2014 Absa Cape Epic were involved in the study. The participants were divided into two groups according to their MTB experience. The experienced group included participants who previously completed more than three 3-day multi-stage MTB events and the novices group included those who has completed less than 3-day multi-stage MTB events. Prior to the event the participants completed a maximal aerobic cycling test and a simulated 40 km time trial (TT). The maximal aerobic test was used to determine 3 work intensity zones based on heart rate (HR) corresponding to blood lactate thresholds (LT: increase in blood lactate concentration of 1 mmol.l-1 above baseline values and the onset of blood lactate accumulation (OBLA), a fixed blood lactate concentration of 4 mmol.l-1). There were no statistically significant differences in the physical, physiological and performance variables measured in the laboratory between the two groups. The exercise intensity during the Cape Epic was measured using telemetric HR monitoring sets. RPE values were noted after each stage of the race. The mean HR was 88.1 ± 5.3% (experienced) and 84.2 ± 11.0% (novices) of maximal HR during the race or 88.9 ± 3.5% (experienced) and 85.9 ± 10.6 (novices) of laboratory determined maximum HR. More time was spent in the “low” HR zone (43.1 % vs 58.5 %, respectively), while only a small amount of time was spent in the “hard” HR zone (7.4% and 6.1%, respectively). The experienced group spent statistically significantly more time in the “moderate” HR zone compared to the novices group (49.5 % vs. 35.4 %). The experienced group performed significantly better during the event compared to the novices group in both the total event time (P = 0.004) and the general classification (P = 0.01). Relative and absolute power output (PO) at OBLA (P = 0.01 and 0.02, respectively) were statistically significant predictors of total event time, while relative peak power output was a significant predictor of general classification for the event (P = 0.02) . The total TT time was a significant predictor of average event HR (P = 0.03). This study showed that this MTB stage race is physiologically very demanding and requires cyclists to have excellent endurance capacity, as well as strength and power. The parameters from the maximal aerobic capacity test correlated better with outdoor performance than parameters from the simulated 40 km TT. Therefore the standard maximal aerobic capacity test are sufficient for testing mountain bikers and sport scientists can continue using this test to prescribe exercise intensity zones for training and events. / AFRIKAANSE OPSOMMING: Die doel van hierdie kwalitatiewe-kwantitatiewe studie was om die oefeningsintensiteit en voorspellers van prestasie tydens ‘n multi-dag bergfiets kompetisie (Absa Cape Epic) van 8 dae lank te bepaal. Drie-en-twintig bergfietsryers (ouderdom 39 ± 9 jaar, lengte 178.8 ± 8.2 cm, liggaamsmassa 74.7 ± 9.1 kg, VO2maks 54 ± 7 ml.kg-1.min-1) wat die 2014 Absa Cape Epic voltooi het, het aan die studie deelgeneem. Die deelnemers is in twee groepe verdeel volgens hulle ervaring in multi-dag bergfiets kompetisies. Die ervare groep was al die deelnemers wat meer as drie 3-dae multi-dag bergfiets kompetisies voltooi het. Die onervare groep was al die deelnemers wat minder as drie 3-dag multi-dag bergfiets kompetisies voltooi het. Voor die kompetisie het al die deelnemers ‘n maksimale aërobiese toets en ‘n gesimuleerde 40 km tydtoets in die laboratorium voltooi. Die maksimale aërobiese toets is gebruik om drie werk intensiteit sones volgens die hartspoed te bepaal, naamlik die hartspoed by die laktaatdraaipunt(‘n toename in bloed [laktaat] van 1 mmol.l-1 bo die basislynwaardes) en die hartspoed by die aanvang van bloedlaktaat akkummulasie (‘n vaste bloed [laktaat] waarde van 4 mmol.l-1). Daar was geen statisties betekenisvolle verskille in die fisiese, fisiologiese en prestasie veranderlikes tussen die twee groepe nie. Die oefeningsintensiteit tydens die Cape Epic was gemeet deur gebruik te maak van hartspoedmonitors. Die RPE waardes was aan die einde van elke skof genoteer. Die gemiddelde hartspoed was 88.1 ± 5.3 % (ervare) en 84.2 ± 11.0 % (onervare) van maksimale kompetisie hartspoed, of 88.9 ± 3.5 % (ervare) en 85.9 ± 10.6 % (onervare) van die maksimale hartspoed soos in die laboratorium gemeet. Die fietsryers het meer tyd spandeer in die “lae” hartspoed sone (43.1 % vs 58.5 %, onderskeidelik), in vergelyking met die “moeilike” hartspoed sone (7.4 % vs 6.1 %, onderskeidelik). Die ervare groep het statisties betekenisvol meer tyd in die “matige” hartspoed sone spandeer (49.5 % vs. 35.4 %) in vergelyking met die onervere groep. Die ervare groep het beter presteer tydens die kompetisie vir beide totale kompetisie tyd (P = 0.004) en algehele klassifikasie (P = 0.01). Relatiewe en absolute krag by aanvang van bloed laktaat akkumulasie was statisties betekenisvolle voorspellers van totale kompetisie tyd (P = 0.01 en 0.02, onderskeidelik), terwyl maksimale krag ‘n statisties betekenisvolle voorspeller was van algehele klassifikasie in die kompetisie (P = 0.02). Die totale tydtoets tyd was ‘n statisties betekenisvolle voorspeller van gemiddelde hartspoed tydens die kompetisie. Die studie het gewys dat hierdie multi-dag bergfiets kompetisie fisiologies baie uitdagend is en dat fietsryers uistekende uithouvermoë kapasiteit, sowel as krag en plofkrag moet besit. Die veranderlikes van die maksimale aërobiese toets het beter met prestasie in die veld gekorreleer as die veranderlikes van die gesimuleerde 40 km tydtoets. Daar word dus afgelei dat die standaard maksimale aërobiese toets voldoende is vir die toetsing van bergfietsryers en sportwetenskaplikes kan aanhou om hierdie toets te gebruik om oefeningsintensiteit sones voor te skryf vir oefensessies en kompetisies.
93

L’archivage numérique des projets « Europan » comme situation d’analyse scientifique du concours d’idées en architecture

Gomes Alves, Lino José 12 1900 (has links)
Il existe somme toute peu de théories du projet offrant une modélisation construite à partir de la complexité et de la diversité du projet d’architecture. Pourtant,certaines situations rassemblant parfois plusieurs dizaines de projets s’offrent d’elles-mêmes comme des situations comparatives et expérimentales : les concours d’architecture, d’urbanisme et de paysage. Le Laboratoire d’étude de l’architecture potentielle de l’Université de Montréal (Aménagement), après avoir développé un système d’archivage numérique des concours canadiens, a entrepris, avec le soutien du Groupement d’intérêt public « Europe des projets architecturaux et urbains », de développer la base de données documentaire des concours d’idées Europan. Au-delà des questions d’archivage numérique, se profilent clairement des possibilités de théorisation s’appuyant sur les logiques d’une base de données, en particulier sur la constitution du diagramme entités et relations, modélisation indispensable à sa traduction informatique. Cette recherche entreprend une première mise à jour de ces éléments conceptuels et tend à montrer que la base de données est un véritable modèle théorique du projet ouvrant sur de nouvelles avenues de recherche et de connaissance. / There are not many theories of project offering a modeling constructed from the complexity and diversity of the architecture project. However, certain situations bringing together dozens of projects, present themselves as comparable and experimental situations: architectural, urban and landscape competitions. The Laboratoire d'étude de l'architecture potentielle from the Université de Montréal (Environmental Design), having developed a system of digital archiving for Canadian competitions, has undertaken, with the support of Groupement d'intérêt public “Europe des projets architecturaux et urbains”, the development of a database comprised of the documentation of competition ideas of Europan. Beyond the issues of digital archiving, there are clearly theorizing possibilities based on the logic of a database, particularly on the structure of the entity/relationship diagram, an indispensable modeling necessary for its computer translation. This research is undertaking a first update of these conceptual elements and suggests that the database is a theoretical model of the project opening up new venues for research and knowledge.
94

Analysis of the agronomic and economic performances of lentil-spring wheat intercrops in organic farming

Viguier, Loïc Arthur 12 July 2018 (has links) (PDF)
Lentil (Lens culinaris Med.) is an important component of the human diet in the world, but in the meantime, Europe produces only 26% of the lentils it consumes. This is partly due to strong agronomic weaknesses that reduce yield such as lodging, bruchid beetles and weeds, especially in organic farming. Intercropping, the simultaneous growing of two or more species in the same field is tested here as an option to reduce these drawbacks and develop organic lentil production. The aims of this thesis were to (1) assess the potential of lentil-spring wheat intercrops to produce organic lentil, (2) understand the mechanisms that explain their performances, and (3) evaluate the profitability of such intercrops. A two-year field experiment was carried out in southwestern France in 2015 and 2016 under organic farming rules. Four lentil and two wheat cultivars were grown as sole crops and intercrops in multiple additive and substitutive designs. Our results showed that the total intercrop attainable grain yield was higher than the mean of sole crops. Yet, lentil yield in intercrop was lower than in sole crop as the result of a strong competition for resources from wheat in early lentil growth stages reducing the number of branches per plant of lentil. This led to lower gross margins of intercrops. However, lentil lodging was strongly reduced in intercrops thus its mechanical harvest efficiency increased. This led to similar mechanically harvested yields of lentil in intercrop and sole crop. Consequently, after mechanical harvest and grain cleaning, the marketable gross margin of intercrops was higher than that of sole crops. Our results suggest that (1) intercrop had no effect on bruchids, (2) the most effective intercrop is when lentil is at sole crop density and wheat at 15-20%, (3) intercrop performance is due to complementary use of N pools through legume N2 fixation and (4) the intensity of interspecific interactions depends on year, wheat density and genotypes. Our work indicates that lentil-spring wheat intercrop can develop organic lentil production but a better understanding of Genotype x Environment x Cropping system interactions may be useful to design optimized managements.
95

"Ça se fait pas ! " : la norme au CM2 / “It’s just not done !” : the norm at school (in 5th grade)

Baumard, Carole 18 May 2018 (has links)
« Ça se fait pas ! ». La norme à l’école est marquée par des nuances et des ambivalences, sources d’incompréhensions et de concurrences, participant à sa fluctuation. L’élève joue un rôle premier devant l’enseignant, acteur, créateur et agent de la norme. La norme en classe présente un caractère inégal, binaire, ambigu, indéterminé et implicite, avec le reflet illusoire d’être partagée par l’élève et l’enseignant. La norme devient homogène pour eux face à une infraction identifiée, majoritairement comme abstention. Dans l’interdépendance entre norme, déviance et acceptation, les limites de l’acceptable en classe se tracent avant tout par rapport à la transgression. L’intrusion de l’affect accentue les fluctuations de la norme et influence les limites du conforme. La norme en classe se décline en situation au sein de l’interaction, dans la dialectique entre conscience et pratique de la norme, qui participe au processus de normalisation. Le registre comportemental est organisateur de la norme et facteur de fluctuations, modulant l’acceptation ou engageant vers la transgression. Les perspectives déontique et pragmatique se concurrencent. Dans la rivalité entre perspectives individuelle et sociale, les besoins sont des facteurs de l’acceptation de la norme, pour chercher à les satisfaire. L’interdépendance entre norme et besoins contribue au processus de normalisation et perturbe l’élève et l’enseignant dans leur rapport à la norme. Les normes en classe se conjuguent ou rivalisent au sein d’un système dynamique et enchevêtré, troublé par les besoins, dont la (l’in)cohérence module le rapport au conforme et engage les acteurs de l’école vers la transgression ou l’acceptation. / “It’s just not done !”. The norm at school is marked by nuances and ambivalences, it is the source of incomprehension and competitions participating in its fluctuation. The student plays the first role in front of the teacher, actor, creator and agent of the norm. The norm provides for an uneven, binary, ambiguous, indefinite and implicit character, offering the imaginary reflection to be shared by the students and teachers. The norm becomes homogeneous for them when confronted with an identified breach, mainly as abstention. In the interdependence animating normality, abnormality and acceptance, the limits of what is considered acceptable at school trace above all with regard to transgression. The intrusion of the affect stresses the fluctuations in the norm and influences the limits of the standard-compliant. The norm is articulated around the situation within the interaction, in the dialectic between consciousness and practice of the norm, which participates in the process of normalization. The behavioral register is the organizer of the norm itself, modulating the acceptance or committing towards the transgression. The deontic and pragmatic perspectives compete amongst themselves. Requirements are factors of the norm’s acceptance, to try to satisfy them. The interdependence between the norm and the requirements participates in the process of normalization and disrupts both students and teachers in their relationship with the norm. The norms at school combine or compete within a system both dynamic and muddled, disturbed by the requirements of coherence which modulate the relationship in compliance and commits school’s actors towards either transgression or acceptance.
96

L’archivage numérique des projets « Europan » comme situation d’analyse scientifique du concours d’idées en architecture

Gomes Alves, Lino José 12 1900 (has links)
Il existe somme toute peu de théories du projet offrant une modélisation construite à partir de la complexité et de la diversité du projet d’architecture. Pourtant,certaines situations rassemblant parfois plusieurs dizaines de projets s’offrent d’elles-mêmes comme des situations comparatives et expérimentales : les concours d’architecture, d’urbanisme et de paysage. Le Laboratoire d’étude de l’architecture potentielle de l’Université de Montréal (Aménagement), après avoir développé un système d’archivage numérique des concours canadiens, a entrepris, avec le soutien du Groupement d’intérêt public « Europe des projets architecturaux et urbains », de développer la base de données documentaire des concours d’idées Europan. Au-delà des questions d’archivage numérique, se profilent clairement des possibilités de théorisation s’appuyant sur les logiques d’une base de données, en particulier sur la constitution du diagramme entités et relations, modélisation indispensable à sa traduction informatique. Cette recherche entreprend une première mise à jour de ces éléments conceptuels et tend à montrer que la base de données est un véritable modèle théorique du projet ouvrant sur de nouvelles avenues de recherche et de connaissance. / There are not many theories of project offering a modeling constructed from the complexity and diversity of the architecture project. However, certain situations bringing together dozens of projects, present themselves as comparable and experimental situations: architectural, urban and landscape competitions. The Laboratoire d'étude de l'architecture potentielle from the Université de Montréal (Environmental Design), having developed a system of digital archiving for Canadian competitions, has undertaken, with the support of Groupement d'intérêt public “Europe des projets architecturaux et urbains”, the development of a database comprised of the documentation of competition ideas of Europan. Beyond the issues of digital archiving, there are clearly theorizing possibilities based on the logic of a database, particularly on the structure of the entity/relationship diagram, an indispensable modeling necessary for its computer translation. This research is undertaking a first update of these conceptual elements and suggests that the database is a theoretical model of the project opening up new venues for research and knowledge.
97

Internetbasierte Ideenwettbewerbe als Instrument der Integration von Kunden in das Innovationsmanagement von Software-Unternehmen

Bretschneider, Ulrich, Ebner, Winfried, Leimeister, Jan Marco, Krcmar, Helmut 22 April 2014 (has links) (PDF)
Insbesondere für kleine und mittlere Softwareunternehmen stellen die Erhöhung der eigenen Innovationskraft und -geschwindigkeit entscheidende Überlebensfragen dar. Der heute als hierfür wichtig hervorgehobene Ansatz der „Open Innovation“ hat sich in der Softwareentwicklungsbrache bislang jedoch kaum durchgesetzt, obwohl den Kunden bzw. Anwendern von Softwareprodukten wegen ihres im Umgang mit den Softwareprodukten gewonnenen Erfahrungswissens ein großes Innovationspotenzial nachgesagt werden kann. Die Durchführung von Ideenwettbewerben stellt in diesem Zusammenhang eine leicht adaptierbare und kostengünstige Methode der Kundenintegration dar. Ziel dieses Beitrages ist, IT-gestützte Ideenwettbewerbe als ein vielversprechendes theoretisches Konzept zur Integration von Kunden in das Innovationsmanagement von Softwareunternehmen vorzustellen.
98

Modulární systém s jednočipovým mikroprocesorem Atmel AVR pro měření při hrách v přírodě / Modular system with single-chip Atmel AVR microprocessor for measuring at outdoor competitions

KROUPA, Bohumil January 2017 (has links)
This diploma thesis deals with the design, construction and programming of universal modular system of timekeeping for children´s outdoor sports games. The basis of this system are single-chip AVR microcontrollers Atmel ATmega 32 and ATmega 328. Data transmission between the modules is realized by a wireless serial port HC-12th. The system is applicable to multiple types of competitions with different types of sensors for time measuring, and it is independent of the continuous supply of electricity.
99

Ekonomika a fungování vybraného maloobchodního řetězce / Economics and management of selected retailer

KALUSOVÁ, Monika January 2013 (has links)
The work is about development of spain retailing chain in the field of textile and clothing. The goal of work is finding development the company during timeframe and comparing position of company with competitions.
100

Machine learning strategies for multi-step-ahead time series forecasting

Ben Taieb, Souhaib 08 October 2014 (has links)
How much electricity is going to be consumed for the next 24 hours? What will be the temperature for the next three days? What will be the number of sales of a certain product for the next few months? Answering these questions often requires forecasting several future observations from a given sequence of historical observations, called a time series. <p><p>Historically, time series forecasting has been mainly studied in econometrics and statistics. In the last two decades, machine learning, a field that is concerned with the development of algorithms that can automatically learn from data, has become one of the most active areas of predictive modeling research. This success is largely due to the superior performance of machine learning prediction algorithms in many different applications as diverse as natural language processing, speech recognition and spam detection. However, there has been very little research at the intersection of time series forecasting and machine learning.<p><p>The goal of this dissertation is to narrow this gap by addressing the problem of multi-step-ahead time series forecasting from the perspective of machine learning. To that end, we propose a series of forecasting strategies based on machine learning algorithms.<p><p>Multi-step-ahead forecasts can be produced recursively by iterating a one-step-ahead model, or directly using a specific model for each horizon. As a first contribution, we conduct an in-depth study to compare recursive and direct forecasts generated with different learning algorithms for different data generating processes. More precisely, we decompose the multi-step mean squared forecast errors into the bias and variance components, and analyze their behavior over the forecast horizon for different time series lengths. The results and observations made in this study then guide us for the development of new forecasting strategies.<p><p>In particular, we find that choosing between recursive and direct forecasts is not an easy task since it involves a trade-off between bias and estimation variance that depends on many interacting factors, including the learning model, the underlying data generating process, the time series length and the forecast horizon. As a second contribution, we develop multi-stage forecasting strategies that do not treat the recursive and direct strategies as competitors, but seek to combine their best properties. More precisely, the multi-stage strategies generate recursive linear forecasts, and then adjust these forecasts by modeling the multi-step forecast residuals with direct nonlinear models at each horizon, called rectification models. We propose a first multi-stage strategy, that we called the rectify strategy, which estimates the rectification models using the nearest neighbors model. However, because recursive linear forecasts often need small adjustments with real-world time series, we also consider a second multi-stage strategy, called the boost strategy, that estimates the rectification models using gradient boosting algorithms that use so-called weak learners.<p><p>Generating multi-step forecasts using a different model at each horizon provides a large modeling flexibility. However, selecting these models independently can lead to irregularities in the forecasts that can contribute to increase the forecast variance. The problem is exacerbated with nonlinear machine learning models estimated from short time series. To address this issue, and as a third contribution, we introduce and analyze multi-horizon forecasting strategies that exploit the information contained in other horizons when learning the model for each horizon. In particular, to select the lag order and the hyperparameters of each model, multi-horizon strategies minimize forecast errors over multiple horizons rather than just the horizon of interest.<p><p>We compare all the proposed strategies with both the recursive and direct strategies. We first apply a bias and variance study, then we evaluate the different strategies using real-world time series from two past forecasting competitions. For the rectify strategy, in addition to avoiding the choice between recursive and direct forecasts, the results demonstrate that it has better, or at least has close performance to, the best of the recursive and direct forecasts in different settings. For the multi-horizon strategies, the results emphasize the decrease in variance compared to single-horizon strategies, especially with linear or weakly nonlinear data generating processes. Overall, we found that the accuracy of multi-step-ahead forecasts based on machine learning algorithms can be significantly improved if an appropriate forecasting strategy is used to select the model parameters and to generate the forecasts.<p><p>Lastly, as a fourth contribution, we have participated in the Load Forecasting track of the Global Energy Forecasting Competition 2012. The competition involved a hierarchical load forecasting problem where we were required to backcast and forecast hourly loads for a US utility with twenty geographical zones. Our team, TinTin, ranked fifth out of 105 participating teams, and we have been awarded an IEEE Power & Energy Society award.<p> / Doctorat en sciences, Spécialisation Informatique / info:eu-repo/semantics/nonPublished

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