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Modèles et méthodes pour la planification de la récolte forestièreGémieux, Géraldine 08 1900 (has links)
Ce projet de recherche a été réalisé avec la collaboration de FPInnovations. Une part des travaux concernant le problème de récolte chilien a été effectuée à l'Instituto Sistemas Complejos de Ingeniería (ISCI) à Santiago (Chili). / La planification de la récolte forestière comporte différents niveaux de planification selon l'horizon de temps du problème et la nature des décisions à prendre.
Dans un premier temps, nous nous intéressons à un problème de planification annuelle de la récolte, à mi-chemin entre la planification tactique et opérationnelle. Ce problème appliqué à l'exploitation forestière au Québec, naît d'un besoin de l'industrie québécoise d'un outil pour la planification annuelle intégrée qui fournit aux équipes de récolte leur calendrier. L'intégration consiste à déterminer les affectations des équipes aux blocs en fonction des besoins des usines, et qui respectent les contraintes de transport, de gestion des stocks, et bien entendu les conditions d'exploitation en forêt.
Plusieurs modèles de types MIP ont été formulés, des approches de résolution adaptées à la structure de chacun des modèles ont été développées.
L'approche par horizon roulant est celle dont les résultats surpassent les deux autres et surtout, améliorent de façon significative les plans usuellement suivis, notamment en réduisant les volumes non livrés aux usines de moitié, ou encore en divisant entre 2 et 6 fois les volumes en stock quand la demande diminue.
De plus, le développement d'une interface pour systématiser le processus de résolution et élargir le nombre d'utilisateurs, est la seconde contribution de la thèse. Cette étape du projet correspond à un transfert de technologie de l'université vers l'industrie.
Le second problème de planification se situe au Chili, est une planification tactique de la récolte dirigée par les prix et demandes en produits finis, ces derniers étant considérés comme des paramètres aléatoires. Le problème stochastique formulé est résolu suivant une méthode de décomposition par scénarios dont le nombre varie entre 10 et 100.
Pour chaque scénario, la solution déterministe, lorsqu'elle est réalisable, est comparée avec celle issue de la résolution du problème stochastique.
La solution déterministe n'est réalisable que pour une dizaine de scénarios parmi 100, et les pertes encourues sont en moyenne de 9%. / Harvest planning has different levels according to the time horizon of the problem and the nature of the decisions to be taken.
Initially, we are interested in an annual harvest scheduling problem, halfway between tactical and operational planning. This problem applied in Qu\'ebec, is motivated by a need from the industry for an integrated tool that provides annual schedules to harvest teams. The integration is to determine demand driven assignments of teams to cutblocks and to manage transportation and inventory accordingly.
Several MIP models have been formulated, and three solution approaches have been developed according to the structure of each model.
The rolling horizon approach performs better than the other two, by improving significantly from the traditional harvest plan, especially by reducing by half non delivered volumes or by dividing between 2 and 6 times volumes in storage when demands decrease.
Another contribution of the thesis is the creation of an interface to systematize solution process and to allow other users. This is the object of a transfer project between academics and industry.
The second problem is a Chilean tactical harvest planning. Harvesting decisions are driven by stochastic demands and prices of final products. The stochastic problem is solved using a heuristic based on a scenario decomposition technique. The number of scenarios considered is between 10 and 100 scenarios.
For each scenario, when the deterministic solution is feasible, it is compared with the stochastic solution for the current scenario. The deterministic solution is only feasible for 10% of the scenarios, and induces losses of 9% in average.
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Planification de la récolte et allocation des produits aux usinesGemieux, Géraldine 08 1900 (has links)
L’industrie forestière est un secteur qui, même s’il est en déclin, se trouve au cœur du débat sur la mondialisation et le développement durable. Pour de nombreux pays tels que le Canada, la Suède et le Chili, les objectifs sont de maintenir un secteur florissant sans nuire à l’environnement et en réalisant le caractère fini des ressources. Il devient important d’être compétitif et d’exploiter de manière efficace les territoires forestiers, de la récolte jusqu’à la fabrication des produits aux usines, en passant par le transport, dont les coûts augmentent rapidement.
L’objectif de ce mémoire est de développer un modèle de planification tactique/opérationnelle qui permet d’ordonnancer les activités pour une année de récolte de façon à satisfaire les demandes des usines, sans perdre de vue le transport des quantités récoltées et la gestion des inventaires en usine. L’année se divise en 26 périodes de deux semaines. Nous cherchons à obtenir les horaires et l’affectation des équipes de récolte aux blocs de coupe pour une année.
Le modèle mathématique développé est un problème linéaire mixte en nombres entiers dont la structure est basée sur chaque étape de la chaine d’approvisionnement forestière. Nous choisissons de le résoudre par une méthode exacte, le branch-and-bound. Nous avons pu évaluer combien la résolution directe de notre problème de planification était difficile pour les instances avec un grand nombre de périodes. Cependant l’approche des horizons roulants s’est avérée fructueuse. Grâce à elle en une journée, il est possible de planifier les activités de récolte des blocs pour l’année entière (26 périodes). / Forest industry is a sector located at the heart of the debate on globalisation and sustainable development, even if it is in decline. For many countries like Canada, Sweden and Chile, the objectives are to maintain a flourishing sector without damaging the environment and to realize the finite nature of resources. It is important to be competitive and to operate effectively on forest territories, from harvesting to manufacturing products, through transport, in a context where costs increase rapidly. This master’s thesis is developing a tactical operational planning model to organize activities for a year to meet requests for factories, without losing sight of the transport of harvested quantities and inventory management factory. The year is divided into 26 periods of two weeks.
We seek harvest teams schedules and assignment to harvest areas (units) for a year. The problem is formulated as a mixed integer programming model, whose structure is based on each stage of the forest supply chain. We choose to solve it by an exact method, branch-and-bound.
We were able to assess how the direct resolution of our planning problem was difficult for instances with a large number of periods. However the rolling horizon approach has proved successful. In a day, we obtained the harvest activities planning for 26 periods.
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Identité d’un territoire rural de marge : essai de modélisation : application à l’Alsace Bossue (1920-30 & 2010) / Identity of a marginal rural territory : modelling test : application to the Alsace Bossue Region (1920-30 and 2010)Dorn, Francis 27 September 2012 (has links)
Le territoire rural de marge est une « entité paradoxale » à la fois tiraillée entre de puissants voisins, des influences culturelles différentes, mais disposant d’une personnalité singulière. Dotée de ressources endogènes limitées, elle est dépendante des aires urbaines de son environnement proche et lointain pour bénéficier d’emplois divers et bien rémunérés, ainsi que pour accéder à des services variés. Pour autant, elle continue à s’individualiser comme une entité propre. De par ses carences, le territoire rural de marge est tributaire d’apports exogènes. Toutefois, cette ouverture est très sélective et autorégulée. L’identité d’un tel territoire se joue à différentes échelles de temps dans une succession de phases d’ouverture et de refondation. Elle est un objet particulièrement complexe. Sa modélisation requiert une exploration, une analyse et une exploitation de cette complexité. Nous la relevons à différents niveaux : emboîtements d’échelle, liaison entre des acteurs divers, de même qu’entre ces acteurs et le territoire lui-même. Nous fondons notre approche de l’objet sur un présupposé majeur : l’identité d’un territoire se décline à l’échelle collective comme à l’échelle individuelle. Il existe entre l’identité territoriale collective et les identités territoriales individuelles une liaison complexe. Notre démarche consiste de ce fait à retrouver les dimensions de l’univers territorial collectif à partir de celles d’une collection d’individus représentatifs du territoire. Par conséquent, la pierre angulaire du travail a été la conception d’un modèle de l’identité territoriale individuelle, dont la traduction graphique est une silhouette. Le profil identitaire collectif est obtenu par la confrontation des profils individuels. L’application du modèle à l’Alsace Bossue et à deux périodes distantes de près de 100 ans a livré quelques résultats. En 1920-30, l’identité de l’Alsace Bossue est une identité insulaire étroite composant avec une ouverture très sélective à des espaces de circulation intergénérationnels. En 2010, l’identité est marquée par une plus grande ouverture, cependant régulée par un arbitrage et une tension généralisés entre des attaches et un besoin d’émancipation, ce que l’on appelle une synergie des contraires. / The marginal rural territory is a “paradoxical entity”, torn between powerful neighbors and diverse cultural influences, but still possessing a unique personality. As it contains limited endogenous resources, this type of territory depends on nearby or distant urban areas in order for its residents to benefit from diverse and well-paying jobs, as well as for access to various services. Even so, it continues to develop an individual identity as a separate entity. Due to its shortcomings, the marginal rural territory is dependent on external provisions. Nevertheless, this openness is very selective and self-regulated. The identity of such a territory is acted out on different time scales in a succession of phases of openness and rebuilding. It is a particularly complex subject. Its modelling requires the exploration, analysis and harnessing of this complexity. We observe it at different levels: changes in scale, links between the various actors, even between these actors and the territory itself. We base our approach toward this subject on a major presupposition: the identity of a territory is defined on a collective as well as an individual scale. The link between collective territorial identity and individual territorial identities is quite complex. Our work consists in tracing the dimensions of the collective territorial universe, based on those of a collection of individuals who represent the territory. As a result, the cornerstone of this work was the creation of a model of individual territorial identity, the graphical translation of which provides a visual representation. The collective identity profile is obtained by the comparison of individual profiles. The application of the model to the Alsace Bossue region during two periods of time separated by nearly 100 years provided us with some results. In 1920-30, Alsace Bossue presented a narrow, insular identity with a very selective openness to inter-generational spaces of circulation. In 2010, its identity is marked by a greater openness, regulated however by generalized arbitration and tension between ties, and by a need for emancipation, what we call a synergy of opposites.
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Planification de la récolte et allocation des produits aux usinesGémieux, Géraldine 08 1900 (has links)
L’industrie forestière est un secteur qui, même s’il est en déclin, se trouve au cœur du débat sur la mondialisation et le développement durable. Pour de nombreux pays tels que le Canada, la Suède et le Chili, les objectifs sont de maintenir un secteur florissant sans nuire à l’environnement et en réalisant le caractère fini des ressources. Il devient important d’être compétitif et d’exploiter de manière efficace les territoires forestiers, de la récolte jusqu’à la fabrication des produits aux usines, en passant par le transport, dont les coûts augmentent rapidement.
L’objectif de ce mémoire est de développer un modèle de planification tactique/opérationnelle qui permet d’ordonnancer les activités pour une année de récolte de façon à satisfaire les demandes des usines, sans perdre de vue le transport des quantités récoltées et la gestion des inventaires en usine. L’année se divise en 26 périodes de deux semaines. Nous cherchons à obtenir les horaires et l’affectation des équipes de récolte aux blocs de coupe pour une année.
Le modèle mathématique développé est un problème linéaire mixte en nombres entiers dont la structure est basée sur chaque étape de la chaine d’approvisionnement forestière. Nous choisissons de le résoudre par une méthode exacte, le branch-and-bound. Nous avons pu évaluer combien la résolution directe de notre problème de planification était difficile pour les instances avec un grand nombre de périodes. Cependant l’approche des horizons roulants s’est avérée fructueuse. Grâce à elle en une journée, il est possible de planifier les activités de récolte des blocs pour l’année entière (26 périodes). / Forest industry is a sector located at the heart of the debate on globalisation and sustainable development, even if it is in decline. For many countries like Canada, Sweden and Chile, the objectives are to maintain a flourishing sector without damaging the environment and to realize the finite nature of resources. It is important to be competitive and to operate effectively on forest territories, from harvesting to manufacturing products, through transport, in a context where costs increase rapidly. This master’s thesis is developing a tactical operational planning model to organize activities for a year to meet requests for factories, without losing sight of the transport of harvested quantities and inventory management factory. The year is divided into 26 periods of two weeks.
We seek harvest teams schedules and assignment to harvest areas (units) for a year. The problem is formulated as a mixed integer programming model, whose structure is based on each stage of the forest supply chain. We choose to solve it by an exact method, branch-and-bound.
We were able to assess how the direct resolution of our planning problem was difficult for instances with a large number of periods. However the rolling horizon approach has proved successful. In a day, we obtained the harvest activities planning for 26 periods.
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Film och mening : En receptionsstudie om spelfilm, filmpublik och existentiella frågor / Movies and Meaning : Studying Audience, Fiction Film and Existential MattersAxelson, Tomas January 2007 (has links)
In what ways and under what circumstances can a movie be a resource for individuals and their thoughts about existential matters? This central research question has been investigated using a both quantitative and qualitative approach. First, a questionnaire was distributed amongst 179 Swedish students to provide a preliminary overview of film habits. The questionnaire was also used as a tool for selecting respondents to individual interviews. Second, thirteen interviews were conducted, with viewers choosing their favourite movie of all time. In the study socio-cognitive theory and a schema-based theoretical tool is adopted to analyze how different viewers make use of movies as cultural products in an interplay between culture and cognition in three contexts; a socio-historic process, a socio-cultural interaction with the world and inner psychological processes. Summarizing the interviews some existential matters dominated. Matters of immanent orientation were in the foreground. Transcendental questions received much less attention. Summarizing the schema-based theoretical question, assessing which cognitive schema structures the narratives were processed through, the study found an emphasis on a combination of two main cognitive structures, person schema and self schema. Detailed person schematic cognitive processes about fictitious characters on the screen and their role model behaviour were combined by the respondents with dynamic cross-references to detailed self schematic introspections about their own characteristics, related to existential matters at some very specific moments in their lives. The viewers in the study seem to be inspired by movies as a mediated cultural resource, promoting the development of a personal moral framework with references to values deeply fostered by a humanistic tradition. It is argued that these findings support theories discussing individualised meaning making, developing ‘self-expression values’ and ‘altruistic individualism’ in contemporary western society.
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Looking at the Marital Horizons of Emerging Adults Through the Lens of Identity FormationBelt, Dallin Alexander 01 March 2016 (has links)
Seventy years ago Erikson proposed successful identity formation in adolescence was the foundation for successful intimacy formation in young adulthood. With the extended period of identity exploration in emerging adulthood, it is unclear if intimacy formation continues to be connected to identity. The purpose of this study was to determine the relationship between identity in three domains of love, work, and worldview with long term views of intimacy using Marital Horizons Theory. Results from a sample of 777 college students in the Project READY dataset indicated that identity formation in love is positively associated with views of marriage, identity formation in work has no significant association with views of marriage, and identity formation in worldview is negatively associated with views of marriage. Implications for the transition into marriage and further identity research are discussed.
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Film och mening : En receptionsstudie om spelfilm, filmpublik och existentiella frågor / Movies and Meaning : Studying Audience, Fiction Film and Existential MattersAxelson, Tomas January 2007 (has links)
<p>In what ways and under what circumstances can a movie be a resource for individuals and their thoughts about existential matters? This central research question has been investigated using a both quantitative and qualitative approach. First, a questionnaire was distributed amongst 179 Swedish students to provide a preliminary overview of film habits. The questionnaire was also used as a tool for selecting respondents to individual interviews. Second, thirteen interviews were conducted, with viewers choosing their favourite movie of all time. In the study socio-cognitive theory and a schema-based theoretical tool is adopted to analyze how different viewers make use of movies as cultural products in an interplay between culture and cognition in three contexts; a socio-historic process, a socio-cultural interaction with the world and inner psychological processes. Summarizing the interviews some existential matters dominated. Matters of immanent orientation were in the foreground. Transcendental questions received much less attention. Summarizing the schema-based theoretical question, assessing which cognitive schema structures the narratives were processed through, the study found an emphasis on a combination of two main cognitive structures, person schema and self schema. Detailed person schematic cognitive processes about fictitious characters on the screen and their role model behaviour were combined by the respondents with dynamic cross-references to detailed self schematic introspections about their own characteristics, related to existential matters at some very specific moments in their lives. The viewers in the study seem to be inspired by movies as a mediated cultural resource, promoting the development of a personal moral framework with references to values deeply fostered by a humanistic tradition. It is argued that these findings support theories discussing individualised meaning making, developing ‘self-expression values’ and ‘altruistic individualism’ in contemporary western society.</p>
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Συστηματική ανάλυση διακλάσεων σε ψαμμιτικούς ορίζοντες στην ευρύτερη περιοχή της Ρουπακιάς ΑχαΐαςΜπεκρής, Μάριος 12 March 2015 (has links)
Συστηματική ανάλυση διακλάσεων σε ψαμμιτικούς ορίζοντες στην ευρύτερη περιοχή της Ρουπακιάς Αχαΐας. Επίδραση καλύμματος Τριπόλεως Γαββρόβου σε συνδυασμό με την Ιόνια επώθηση και την κίνηση της ζώνης Πίνδου προς Δυσμάς. Φλυσχικά τεμάχη διατέμνονται από μικρο και μακρο ρωγματώσεις οφειλόμενες σε πεδία τάσεων εφελκυσμού / Systematic analysis of discontinuities in sandstone horizons in Greater Roupakias Achaia. Effect cover Tripoli Gavvrovou combined with Ionian overthrust and bustle of Pindos zone to the west. Flysch pieces dissected from micro and macro cracks due to tensile stress fields.
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Desempenho de modelos de otimização em diferentes horizontes de investimento no mercado brasileiro / Optimization models performance in different investment horizons for brazilian marketSchlender, Sergio Guilherme 27 January 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This paper proposes a comparative analysis of optimization models through different investment horizons in the Brazilian market. The use of models is based on modifications of the sample covariance matrix (such as shrinkage methods and detection of outliers models) and the replacement as measure of risk of the variance by the Value at Risk (VaR) and Expected Loss (ES). The analysis separates in two different times: in-sample, understood in daily returns between January 2003 and December 2010; and another out-of-sample on a daily basis of returns from January 2010 to December 2013. As results, this paper observe that both, in-sample as the investment horizon out-of-sample long-term, models involved in risk measures presented better performance, especially in case of market crash. In short-term and medium-term investment horizons, models of minimum-variance and mean-variance obtained the best results. Economically, the investor can use the models for increased safety in the allocation assets in turbulent periods. In theoretical implications, there is the importance of not using excessively a single optimization model for the management of portfolios. / O presente trabalho propõe uma análise comparativa dos modelos de otimização por meio de diferentes horizontes de investimento no mercado brasileiro. A utilização dos modelos é baseada nas modificações da matriz de covariância amostral (como os métodos de encolhimento e modelos de detecção de observações extremas) e na substituição da variância pelo Valor em Risco (VaR) e a Perda Esperada (ES) como medida de risco. A análise separa em dois momentos distintos: um dentro da amostra, em retornos diários compreendidos entre janeiro de 2003 a dezembro de 2010; e outro fora da amostra, numa periodicidade diária de retornos de janeiro de 2010 a dezembro de 2013. Como resultados, observa-se que tanto dentro da amostra como no horizonte de investimento de longo prazo fora da amostra, modelos ligados às medidas de risco apresentaram melhores desempenhos, sobretudo em caso de quebra do mercado. No curto e médio prazos de investimento, as estratégias de mínima-variância e média-variância obtiveram os melhores resultados. Economicamente, o investidor pode se utilizar dos modelos para maior segurança na alocação de seus ativos em períodos turbulentos. Em implicações teóricas, verifica-se a importância da não utilizar excessivamente apenas um único modelo de otimização para a gestão de portfólios.
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Proactive Energy Optimization in Residential Buildings with Weather and Market ForecastsSimmons, Cody Ryan 01 July 2019 (has links)
This work explores the development of a home energy management system (HEMS) that uses weather and market forecasts to optimize the usage of home appliances and to manage battery usage and solar power production. A Moving Horizon Estimation (MHE) application is used to find the unknown home model parameters. These parameters are then updated in a Model Predictive Controller (MPC) which optimizes and balances competing comfort and economic objectives. Combining MHE and MPC applications alleviates model complexity commonly seen in HEMS by using a lumped parameter model that is adapted to fit a high-fidelity model. HVAC on/off behaviors are simulated by using Mathematical Program with Complementary Constraints (MPCCs) and solved in near real-time with a nonlinear solver. Removing HVAC on/off as a discrete variable decreases potential solutions and consequently reduces solve time and increases the probability of reaching a more optimal solution. The results of this work indicate that energy management optimization significantly decreases energy costs and balances energy usage more effectively throughout the day compared to a home with regular temperature control. A case study for Phoenix, Arizona shows an energy reduction of 21% and a cost reduction of 40%. Homes using this home energy optimization will contribute less to the grid peak load and therefore, improve grid stability and reduce the amplitude of load following cycles for utilities. This case study combines renewable energy, energy storage, forecasts, cooling system, variable rate electricity plan and a multi-objective function allowing for a complete home energy optimization assessment. There remain several challenges, including improved forecast models, improved computational performance to allow the algorithms to run in real-time, and mixed empirical / first principles machine learning methods to guide the model structure.
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