Urban and regional planning, from a professional standpoint, is built on a history of preservation, with the backdrop of a perennial quest to define itself for the benefit of both laypeople and its own members. Consequently, different stages of planning throughout the twentieth century relate to simultaneous cultural changes that have caused the re-definition and re-focusing of professional efforts. From the original concentration on rational thought that coincided with the planner as objective expert with the ability to identify and promote the public interest, to the civil rights movement of the late twentieth century that embodied postmodern ideas such as advocacy, collaboration, and communication, the concept of who the planner is and what role he or she plays has developed over time. In parallel, the structures planners use to deliver their services have altered. While the shift from the traditional concept of the public sector to quasi-public and private applications has been well documented, the structures of the twenty-first century such as multinationals, public-private partnerships, and multi-disciplinary arrangements are less studied and understood. Multi-disciplinary practices (MDPs), in particular, garner little attention from the academic or professional planning spheres. While the legal and accounting professions are scrambling for a clear policy direction on cross-discipline collaboration, planners do not seem to have diverted much attention to whether or not they have a future. Indeed, the existence of MDPs provokes the return of the question of what role planners should play, and whether they should be a distinct specialized profession, or an entity with a mandate to coordinate other professions with an eye to long-term planning for the public good. This analysis attempts to qualitatively assess whether MDPs should be supported or rejected by the planning discipline, and how the profession should be addressing the answer. / Thesis (Master, Urban & Regional Planning) -- Queen's University, 2007-09-28 11:25:12.401

Si les travaux menés dans le domaine des sciences de la décision ont permis de résoudre des problèmes variés, la capacité pour un agent à être autonome dans le choix de ses objectifs reste un problème difficile à traiter. Cette capacité est pourtant indispensable à l'autonomie dans son environnement pour un agent. Cette thèse a pour objectif de permettre à un robot de planifier ses actions pour de multiples objectifs contradictoires, dans un environement probabiliste et avec des ressources. La première contribution de ce travail est la proposition d'un nouveau modèle pour les objectifs, la motivation, constitué à partir d'un automate. Celui-ci décrit l'évolution de chaque objectif à l'aide d'états et de transitions correspondant à la réalisation de tâches, et définit les gains de récompenses. La deuxième contribution concerne une méthode de planification utilisant les motivations. Cette méthode est hiérarchique, proposant de résoudre la réalisation des tâches déterminantes pour les motivations dans un premier temps. En exploitant le contexte spécifique de chaque tâche, nous pouvons calculer rapidement leur politique et calculer leur modèle d'exécution, que nous appelons macro-action. Nous utilisons ensuite ces macro-actions dans un processus de planification local de haut-niveau, permettant de retourner un plan conditionnel des macro-actions à exécuter, que nous appelons agenda des macro-actions. Pour résoudre un problème dans sa longueur, nous proposons d'incluer ce système de planification dans une architecture délibérative qui permettra de contrôler l'exécution des agenda et d'en produire de nouveaux. / If the litterature of ​​decision-making has addressed a variety of problems, the ability to make an agent autonomous in the choice of its goals remains a difficult issue to address. This capacity is nevertheless essential for an agent in order to be automous in its environment. This thesis aims at allowing a robot to plan its own actions for multiple concurrent objectives, in a probabilistic environment and with resources. The first contribution of this work is the proposal of a new model for the objectives, the motivations, constituted from an automaton. Motivations describe the evolution of each objective using states and transitions corresponding to the realisation of tasks, and define the reward gains. The second contribution concerns a planning method that makes use the motivations. This method is hierarchical and proposes at first to solve the realisation of the tasks that are relevant for the motivations. By exploiting the specific context of each task, we can quickly compute their policy and calculate their execution model, which we call macro-action. We then use these macro-actions in a high-level local planning process, allowing us to return a conditional plan of the macro-actions to be executed, which we call macro-actions agenda. To solve a problem over time, we propose to include this planning system in a deliberative architecture that will control the execution of the agenda and produce new ones.

In this dissertation, we study inventory and revenue management problems for perishable products with customer choice considerations. This dissertation is composed of six chapters. In Chapter 1, we provide an overview and the motivation of problems. Subsequently, in Chapter 2, we propose a joint inventory and pricing problem for a perishable product with two freshness levels. After a stochastic time, a fresh item turns into a non-fresh item, which will expire after another random duration. Under an (r, Q) ordering policy and a markdown pricing strategy for non-fresh items, we formulate a model that maximizes the long-run average profit rate. We then reduce the model to a mixed-integer bilinear program (MIBLP), which can be solved efficiently by state-of-the-art commercial solvers. We also investigate the value of using a markdown strategy by establishing bounds on it under limiting regimes of some parameters such as large market demand. Further, we consider an Economic Order Quantity (EOQ)-type heuristic and bound the optimality gap asymptotically. Our results reveal that although the clearance strategy is always beneficial for the retailer, it may hurt customers who are willing to buy fresh products. In Chapter 3, we extend this model to the dynamic setting with multiple freshness levels of perishable products. Due to the complexity of the problem, we study the structural properties of value function and characterize the structure of the optimal policies by using the concept of anti-multimodularity. The structural analysis enables us to devise three novel and efficient heuristic policies. We further extend the model by considering donation policy and replenishment system. Our results imply that freshness-dependent pricing and dynamic pricing are two substitute strategies, while freshness-dependent pricing and donation strategy are two complement strategies for matching supply with demand. Also, high variability in product quality under dynamic pricing benefits the firm, but it may result in significant losses with a static pricing strategy. In Chapter 4, we study a joint inventory-pricing model for perishable items with fixed shelf lives to examine the effectiveness of different markdown policies, including single-stage, multiple-stage, and dynamic markdown policies both theoretically and numerically. We show that the value of multiple-stage markdown policies over single-stage ones asymptotically vanishes as the shelf life, market demand, or customers’ maximum willingness-to-pay increase. In chapter 5, with a focus on blood products, we optimize blood supply chain structure along with the operations optimization. Specifically, we study collection, production, replenishment, issuing, inventory, wastage, and substitution decisions under three different blood supply chain channel structures, i.e., the decentralized, centralized, and coordinated. We propose a bi-level optimization program to model the decentralized system and use the Karush–Kuhn–Tucker (KKT) optimality conditions to solve that. Although centralized systems result in a higher performance than decentralized systems, it is challenging to implement them. Thus, we design a novel coordination mechanism to motivate hospitals to operate in a centralized system. We also extend the model to the case with demand uncertainty and compare different issuing and replenishment policies. Analysis of a realistic case-study indicates that integration can significantly improve the performance of the system. Finally, Chapter 6 concludes this dissertation and proposes future research directions. / Dissertation / Doctor of Philosophy (PhD)

The recent generation of Agile Earth Observation Satellite (AEOS) has emerged to be highly effective due to its increased attitude maneuvering capabilities. However, due to these increased degrees of freedom in maneuverability, the scheduling problem has become increasingly difficult than its non-agile predecessors. The AEOS scheduling problem consists of finding an optimal assignment of user-requested imaging tasks to the respective AEOSs in their orbits by satisfying the operational resource constraints in a specified time frame. Some of these tasks might require imaging the same area of interest (AOI) multiple times, while in some tasks, the AOIs are too large for the AEOS to image in a single attempt. Some tasks might even arise while the AEOSs are preoccupied with existing tasks. This thesis focuses on formulating the AEOS scheduling models where onboard energy and memory constraints while operating and the task specifications are diverse. A mixed-integer non-linear scheduling problem with a reward factor has been considered in order to handle multiple scan requirements for a task. Although initially, it is assumed that the AOIs are small, this work is extended to a three-stage optimization framework to handle the segmentation of large AOIs into smaller regions that can be imaged in a single scan. The uncertainty regarding scan failure is handled through a Markov Decision Process (MDP). These two proposed methods have significant benefits when tasks are available to schedule prior to the mission. However, they lack the flexibility to accommodate newly arrived tasks during the mission. When multiple new tasks arrive during the mission, predictive scheduling based on learning historical data of task arrivals is proposed, which can schedule tasks in an online manner faster than complete rescheduling and minimize disruption from the original schedule. Evolutionary optimization-based solution methodologies are proposed to solve these models and are validated with simulations. / Thesis / Doctor of Philosophy (PhD)

No description available.

Dans cette thèse, nous nous intéressons à cette gestion des données dans les réseaux de capteurs sans fil intégrés dans un contexte IoT. Plus précisément, nous aborderons la problématique du stockage des données au sein même du réseau de capteurs en se posant la question suivante : Comment stocker provisoirement les données dans le réseau de capteurs de sorte que ces données soient facilement accessible par les consommateurs tout en assurant le meilleur compromis entre la fiabilité de livraison des donnés et la préservation des ressources énergétiques des capteurs ?Il s'agit dans un premier temps de proposer un système fiable de stockage de données basé sur la théorie du codage réseau et sur le modèle de communication « Publish/Subscribe ». Le système proposé est adapté à l'architecture des réseaux de capteurs ainsi qu'aux besoins des applications et services IoT localisés. Pour démontrer la validité du système de stockage proposé, des évaluations de performances au travers d'une analyse mathématique et de simulations sont conduites. Celles-ci montrent clairement une augmentation de la fiabilité de la livraison des données aux consommateurs avec un taux de livraison des paquets de 80% en moyenne. Afin d'améliorer encore plus les performances du système de stockage de données, nous proposons, dans un second temps, l'optimisation du système afin que celui-ci puisse réaliser le stockage des données de manière adaptative et autonome, tout en assurant le meilleur compromis entre fiabilité et coût. Ce dernier se traduit par l'impact du système de stockage sur la consommation d'énergie du réseau de capteurs sans fil. À notre connaissance, notre système est le premier à proposer d'assurer la fiabilité du stockage des données en fonction des demandes des services et des conditions du réseau. L'évaluation des performances, par simulation, de notre système de stockage adaptatif et autonome montre que l'optimisation du stockage des données (formulée sous forme d'un processus de décision Markovien (MDP)) selon les conditions de fonctionnement du réseau permet l'accès à 70% de données en plus comparativement au système non-adaptatif proposé précédemment. Ce résultat est obtenu tout en augmentant la durée de vie du réseau de 43%.Après avoir travaillé sur l'aspect quantitatif des performances du réseau à travers une étude sur le compromis coût - consommation énergétique, nous nous intéresserons dans la troisième contribution de cette thèse à l'utilisation de notre système de stockage dans des réseaux de capteurs sans fil disposant de cycles de services (cycle d'endormissement-réveil) variables. Aujourd'hui, les réseaux de capteurs reposant sur le standard 802.15.4 peuvent utiliser des cycles de services variables et avoir recours à l'endormissement des nœuds dans le but d'économiser leur énergie. Dans une première partie de cette contribution, nous avons ainsi proposé une amélioration du mécanisme de gestion du cycle de service (duty cycle) du standard 802.15.4 afin de le rendre dynamique et adaptable au trafic réseau. L'évaluation des performances par simulations de l'amélioration proposée montre que celle-ci aboutit à une économie d'énergie très significative tout en permettant au réseau de capteurs sans fil de remplir sa mission de prise en charge du trafic généré. Dans une seconde partie de cette contribution, nous évaluons les performances de notre système de stockage de données dans le but d'évaluer si un tel mécanisme pourrait cohabiter positivement avec un mécanisme de cycle de service variable (condition d'exploitation réaliste du réseau). L'évaluation des performances montre que l'activation d'un cycle de service variable dans le réseau de capteurs n'apporte aucune amélioration au niveau de la consommation énergétique mais que le compromis optimal entre la fiabilité et la consommation énergétique obtenu par notre système de stockage adaptatif et autonome n'est pas non plus affecté, celui-ci est maintenu / Wireless Sensor Networks (WSN) are made up of small devices limited in terms of memory, processing and energy capacity. They work interconnected and autonomously in order to monitoring a region or an object of interest. The evolution in the development of devices more powerful (with new capability such as energy harvesting and acting) and less expensive made the WSNs a crucial element in the emergence of Internet of Things (IoT). Nonetheless, assuming the new applications and services offered in the IoT scenario, new issues arise in the data management performed in the WSNs. Indeed, in this new context, WSNs have to deal with a large amount of data, now consumed on-demand, while ensure a good trade-off between its reliability and retrievability, and the energy consumption. In the scope of this thesis, we are interested in the data management in the WSN in the context of IoT realm. Specifically, we approach the problem of in-network data storage by posing the following question: How to store data for a short term in the WSNs so that the data could be easily retrieved by the consumers while ensuring the best trade-off between data reliability and conservation of energy resources? Foremost, we propose a reliable data storage scheme based on coding network, and assuming a communication model defined by the Publish/Subscribe paradigm. We validate the efficiency of our proposal by a theoretical analyses that is corroborate by a simulation evaluation. The results show that our scheme achieves a reliability of 80% in data delivery with the best cost-benefit compared to other data storage scheme. Aiming to further improve the performance of the data storage scheme proposed in our first contribution, we propose its optimization (modeling it as a Markov Decision Process (MDP)) in order to store data with optimal trade-off between reliability and communication overhead (in this context, also seen as energy consumption), and in an autonomously and adaptive way. For the best of our knowledge, our optimized data storage scheme is the only to ensure data reliability while adapt itself according to the service requirements and network condition. In addition, we propose a generalization of the mathematical model used in our first contribution, and a system model that defines the integration of WSNs performing our data storage scheme in the context for which it was envisaged, the IoT realm. Our performance evaluation shows that our optimization allows the consumers to retrieve up to 70% more packets than a scheme without optimization whereas increase the network lifetime of 43%.Finally, after being interested in finding the best trade-off between reliability and cost, we now focus on an auxiliary way to reduce the energy consumption in the sensor nodes. As our third contribution, we propose a study, in two parts, to measure how much a node activity scheduling can save energy. First, we propose an improvement in the duty cycle mechanism defined in the 802.15.4. Then, we propose a duty cycle mechanism introduced into our data storage scheme aiming at saving energy in the storage nodes. The simulation results show that our solution to the duty cycle mechanism in 802.15.4 led in considerable saving in energy costs. However, regarding duty cycle in our data storage scheme, it did not end up in more energy saving. Actually, as our optimized scheme already saves as much resource energy as possible while ensuring high reliability, the duty cycle mechanism can not improve the energy saving without compromise the data reliability. Nonetheless, this result corroborates that our scheme, indeed, performs under the optimal trade-off between reliability and communication overhead (consumption energy)

[pt] A crescente percepção da importância da proteção ambiental e dos impactos associados aos bens de consumo tem aumentado o interesse no desenvolvimento de métodos para melhor compreender e lidar com estes impactos. Neste contexto, a metodologia berço-ao-berço (C2C) descreve uma maneira de projetar produtos com ciclos de vida (biológicos ou técnicos) fechados, para evitar a perda de nutrientes do solo e de matéria-prima não renovável. Na indústria de mobiliário, a madeira tem sido cada vez mais substituída por painéis industrializados (MDF e MDP), que oferecem maior produtividade, matéria prima renovável e um posicionamento sustentável de mercado. A maneira como são descartados hoje, no entanto, não está alinhada com esse discurso. A partir de revisão bibliográfica, visitas e entrevistas, o ciclo de vida do móvel de MDF e MDP foi descrito para que, posteriormente pudessem ser avaliadas as possibilidades de adequação à metodologia C2C. Ao final do trabalho, concluiu-se que por ser um material que pode ser adequado ao ciclo biológico ou ao ciclo técnico, seu potencial para o fechamento do ciclo é grande, no entanto devem ser superadas barreiras como a utilização de componentes nocivos à saúde em sua composição e o descarte fragmentado dos móveis. / [en] The perception that human activities might have significant impact in the environment led, in the last decades, to the development of policies and methodologies to better understand and handle the subject. The United Nations Conference on Environment and Development (UNCED), also known as the Rio Summit or ECO-92, was a major event in that direction. More than one hundred heads of state gathered with other representatives from the society, industries and environmentalists to discuss about sustainable development and global warming (MCDONOUGH and BRAUNGART, 2002). One of the negotiation s result was the definition of the eco-eficiency strategy, that guided the industry approach to the issue in the two past decades. Reducing direct and indirect environmental impact in every possible opportunity became one of the main strategies to reach such eco-eficiency. To identify these possibilities, the product s life cycle became focus of studies from researchers, companies and governments. The Law no. 12.305/2010, for example, defines life cycle as the series of stages related to de development of the product, the acquisition of raw material, the production process, consumption and final disposal. In a similar way, the International Standards Organization (ISO) defines life cycle as consecutive and interlinked stages of a product system, from raw material acquisition or generation from natural resources to final disposal. 14000 series os norms, from ISO, is one of the main tools to provide inputs to this debate. More specific, 14020 and 14040 regulate environmental labels and life cycle assessment (LCA). While labels are essential to communicate to the market the characteristics of a product, LCA is one of the most complete tool to help decisions related to the development of products or services. It can be applied to the whole life cycle, from raw material extraction to disposal, or in specific stages, and allows for a comparison between two different solutions based in the same functional unit, or objective, making it easier to identify the least negative impact. Cradle-to-cradle methodology (C2C) developed by MCDONOUGH and BRAUNGART (2002) takes a step further in the approach of the environmental impact reduction, suggesting that instead of reducing the negative impact, products and services should have a positive impact in the environment.

No description available.

Developing nanoparticulate delivery systems that will allow easy movement and localisation of a drug to the target tissue and provide more controlled release of the drug in vivo is a challenge for researchers in nanomedicine. The aim of this study was to evaluate the biodistribution of two nano-delivery systems namely, poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles containing samarium-153 oxide ([153Sm]Sm2O3) as radiotracer and solid lipid nanoparticles (SLNs) containing technetium-99m-methylene diphosphonate (99mTc-MDP), after oral and intravenous administration to rats to prove that orally administered nanoparticles indeed alter the biodistribution of a drug as compared to the drug on its own. Stable samarium-152 oxide ([152Sm]Sm2O3) was encapsulated in polymeric PLGA nanoparticles. These were then activated in a nuclear reactor to produce radioactive [153Sm]Sm2O3 loaded-PLGA nanoparticles. Both the stable nanoparticles as well as the fully decayed activated nanoparticles, were characterized for size, Zeta potential and morphology using dynamic light scattering and scanning electron microscopy (SEM) or transmission electron microscopy (TEM), respectively. SLNs were a form of delivery system which was used to encapsulate the radiotracer, 99mTc-MDP. 99mTc-MDP SLNs were characterized before and after encapsulation for size and Zeta potential. Both nanoparticle compounds were orally and intravenously (IV) administered to rats in order to trace their uptake and biodistribution through imaging and ex vivo biodistribution studies. The PLGA nanoparticles containing [153Sm]Sm2O3 were spherical in morphology and smaller than 500 nm, therefore meeting the objective of producing radiolabelled nanoparticles smaller than 500 nm. Various parameters were optimized to obtain an average particle size ranging between 250 and 300 nm, with an average polydispersity index (PDI) ≤ 0.3 after spray drying. The particles had a Zeta potential ranging between 5 and 20 mV. The Sm2O3-PLGA nanoparticles had an average size of 281 ± 6.3 nm and a PDI average of 0.22. The orally administered [153Sm]Sm2O3-PLGA nanoparticles were deposited in various organs which includes bone with a total of 0.3% of the Injected Dose (ID) per gram vs the control of [153Sm]Sm2O3which showed no uptake in any organs except the GI-tract. The IV injected [153Sm]Sm2O3-PLGA nanoparticles exhibit the highest localisation of nanoparticles in the spleen (8.63%ID/g) and liver (3.07%ID/g). The 99mTc-MDP-labelled SLN were spherical and smaller than 500 nm. Optimization of the MDP-loaded SLN emulsions yielded a slightly higher PDI of ≥0.5 and a size range between 150 and 450 nm. The Zeta potential was between -30 and -2 mV. The MDP-loaded SLN had an average size of 256 ± 5.27 and an average PDI of 0.245.The orally administered 99mTc-MDP SLN had the highest localisation of nanoparticles in the kidneys (8.50%ID/g) and stomach (8.04%ID/g) while the control, 99mTc-MDP had no uptake in any organs except the GI-tract. The IV injected 99mTc-MDP SLN also exhibited a high localisation of particles in the kidneys (3.87%ID/g) followed by bone (2.66%ID/g). Both the IV and oral 99mTc-MDP SLN reported significantly low deposition values in the heart, liver and spleen. Based on the imaging and the biodistribution studies, it can be concluded that there was a significant transfer of the orally administrated radiolabelled nanoparticles from the stomach to other organs vs the controls. Furthermore, this biodistribution of the nano carriers warrants surface modification and optimisation of the nanoparticles to avoid higher particle localisation in the stomach. / MSc (Pharmaceutics), North-West University, Potchefstroom Campus, 2014

Previous studies have shown that the formulation of an active pharmaceutical ingredient (API) entrapped in the Pheroid® (Pheroid for simplification) delivery system enhances absorption of the API, suppresses its metabolism, and may contribute to an increase in the quantity of the API present at the site of action. Higher drug levels at the active site should particularly increase the effectiveness of a drug with a narrow therapeutic index and reduce the incidence of the resistance that may otherwise arise if the sub-therapeutic levels of the API are in contact with the site of interest. Two approaches were followed in this study. First, the radioactive tracer molecule 99mTechnetium methylene diphosphonate (99mTc MDP) was used. Intravenously injected 99mTc MDP is an extremely effective bone-seeking radiopharmaceutical used in the diagnosis of bone disorders such as bone metastases in patients. However, if entrapped inside a Pheroid vesicle, it will locate to that site, usually an organ, where the Pheroid vesicles may tend to accumulate. Experiments conducted with 99mTc MDP alone or with Pheroid will therefore establish how efficiently Pheroid vesicles localize and will also indicate the preferred site of localization inside a body. The process would involve the oral administration of 99mTc MDP either alone or with Pheroid, involving an animal model. It would also involve tracking localization to particular organs, blood or other sites. The second approach requires the use of chloroquine (CQ) labeled with carbon-14 (14C-CQ,) to compare absorption of the drug both with and without the Pheroid system. The intention was to compare oral absorption and bio-distribution of 14C-CQ administered either alone or entrapped in the Pheroid system. It was also possible to establish whether the Pheroid affects the biological half-lives of the CQ and residence times of CQ in the different organs of the body. Absorption of free 99mTc MDP (orally adminsistered) through the intestinal tract is negligible but it was anticipated that increased absorption will be observed when 99mTc MDP was entrapped in the Pheroid system. In the 99mTc MDP study, different routes of administration of 99mTc MDP, as well as 99mTc MDP entrapped and not entrapped in the Pheroid system, were investigated. The Sprague Dawley rat was used as animal model. Rats were divided into three groups of four rats each for the first part of the study. In the first group, only 99mTc MDP was injected intravenously in order to establish natural distribution of the 99mTc MDP. For the second group, 99mTc MDP was administered orally in order to establish whether there was any absorption through the intestinal tract. In the third group, the 99mTc MDP was entrapped in Pheroid vesicles and this formulation was administered orally in order to establish whether the Pheroid system enhanced oral absorption. The animals were sacrificed four hours after administration and organs were harvested and were counted for radioactivity to determine the percentage of injected/administrated dose in each organ. After oral administration, the Pheroid system was found to have facilitated absorption of 99mTc MDP through the intestinal tract into the blood. 99mTc MDP concentrations in the femur, although lower, were still comparable with that observed after intravenous administration of 99mTc MDP in the absence of Pheroid. Thus, overall, excellent absorption of the Pheroid entrapped 99mTc MDP through the intestinal tract was seen in contrast to little or zero absorption of the compound in the reference formulations. The half-life of the radio-labelled compound in the blood was prolonged after oral administration owing to the Pheroid. To investigate the bio-distribution of radioactive chloroquine (14C-CQ) Sprague Dawley rats were divided into two groups of four rats each. In the first group, 14C-CQ in deionised (DI) water was administered orally, and in the second group 14C-CQ entrapped in Pheroid vesicles was administered, also orally. The animals were sacrificed one, two and four hours after administration and subjected to comprehensive macroscopic inspection. All the organs were harvested and radioactivity was determined with liquid scintillation after applicable sample preparation. The Pheroid system produced much higher organ and blood concentrations of 14C-CQ and enhanced residence times within the organs and blood in comparison with that of 14C-CQ administered alone. Commercial applications of these results are possible, as a number of radiopharmaceutical products can presently be administered only intravenously. The added potential of these new Pheroid formulations could be of significance in the treatment of malaria, as chloroquine is inexpensive and widely available. Another point of interest is that the use of these formulations may enable micromolar drug concentrations to be achieved using drug dosage regimes that usually produce only nanomolar levels. However, safety aspects would have to be carefully monitored. / PhD (Pharmaceutics), North-West University, Potchefstroom Campus, 2015