Le travail présenté s'inscrit dans le contexte de la théorie des systèmes linéaires dans les dioïdes. La motivation initiale de cette étude a été de contribuer à l'analyse et la commande de systèmes linéaires dans max-plus en utilisant spécifiquement une approche géométrique. La contribution de cette thèse est centrée sur deux problèmes. La première partie est dédiée à l'étude de la relation entre les notions d'invariance contrôlée et d'invariance contrôlée par retour d'état dynamique dans un semi-anneau. Cette relation permet de montrer l'équivalence de ces deux notions. La deuxième partie concerne un problème original dans la théorie des systèmes linéaires dans max-plus, il s'agit de la synthèse d'une loi de commande par retour d'état, qui permette de satisfaire un ensemble de spécifications exprimées sous la forme de restrictions sur l'état du système, avec une approche géométrique. Il s'agit plus précisément de commander des systèmes à événements discrets décrits par un modèle linéaire dans max-plus. Nous définissons et caractérisons l'ensemble des conditions initiales admissibles, lesquelles sont à l'origine de solutions non décroissantes. Les restrictions temporelles imposées à l'espace d'état du système sont décrites par le semi-module défini par l'image de l'étoile de Kleene de la matrice associée aux restrictions temporelles. Les propriétés géométriques de ce semi-module permettant de garantir que l'évolution du système en boucle fermée satisfasse les restrictions sont étudiées. Des conditions suffisantes concernant l'existence d'une loi de commande causale par retour d'état statique sont présentées. Le calcul des lois de commande causales est également présenté. Pour illustrer l'application de cette approche, deux problèmes de commande sont présentés. / This work is in the context of the theory of linear Systems in the dioids. The initial motivation of this study was to contribute to the analysis and control of max-plus linear systems, specifically using a geometric approach. The contribution of this thesis focuses on two issues. The first part is dedicated to study of the relationship between the concepts of controlled invariance and dynamic state feedback controlled invariance in a semi-ring. This relationship allows us to show the equivalence of these two concepts. The second part relates to a new problem in the theory of max-plus linear systems, it is the synthesis, with a geometric approach, of a static state feedback control law, in order to satisfy a set of specifications that apply to the state space of the system. This is specifically to control of discrete event systems described by a linear model in max-plus. We define and characterize the set of admissible initial conditions, which are the cause of non-decreasing solutions. Temporal restrictions on the system state space are described by the semi-module defined by the image of the Kleene star of the matrix associated with time restrictions. The geometric properties of this semi-module are studied. Sufficient conditions for the existence of a causal control law by static feedback are presented. Calculating causal control laws is also presented. To illustrate the application of this approach, two control problems are presented.

Hintergrund: Zahlreiche Studien haben den therapeutischen Nutzen von systemischem Antibiotika in der Behandlung schwerer Parodontitis gezeigt. Bisher ist allerdings noch nicht geklärt, welches antibiotische Behandlungkonzept das Geeignetste ist. Daher sollen in einer randomisierten, klinischen Blindstudie zwei verschiedene, systemische Antibiotika adjuvant zur konventionellen, instrumentellen Behandlung von Patienten mit rapid progressiver Parodontitis (RPP) miteinander verglichen werden. Material und Methode: 33 Patienten mit klinisch und radiologisch gesicherter RPP-Diagnose wurden auf 2 Gruppen verteilt: (1) AM-Gruppe (n=17): 500 mg Amoxicillin und 250 mg Metronidazol (3*/ Tag - 10 Tage), (2) D-Gruppe (=16) 200mg Doxycyclin am 1.Tag und 100mg Doxycyclin 13 Tage. Zu Beginn erhielten alle Patienten 3* eine professionelle Zahnreinigung, und anschlie§end Scaling und Wurzelglättung unter Lokalanästhesie in 2 Sitzungen. 3 Monate später wurde ein Recall und die Antibiose durchgeführt. Im Abstand von jeweils 3 Monaten erfolgten 2 weitere Recallsitzungen. Nach erfolgreicher Mundhygieneinstruktion und zu allen Recallsitzungen wurden alle klinischen Parameter wie Taschentiefe, relatives Attachmentlevel und das Bluten bzw. Pus nach Sondieren mit der Florida probe eruiert. Die Bestimmung 8 verschiedener Parodontalpathogene wurde mit dem DNS-Sondentest von Meridol durchgeführt. Die mikrobiologischen Proben wurden mit sterilen Papierspitzen an den vier tiefsten Taschen vor der Antibiose und zu den anschlie§enden Recalls entnommen und mit der Gensondentechnik im Labor der Wybert GmbH elmex Forschung, Lörrach, analysiert. Zur Bestimmung des IL-1-Genpolymorphismus wurde venöses Blut in der 1. Sitzung abgenommen. Die Auswertung erfolgte mit dem GenoType(R) PRTest (Hain Diagnostika GmbH). Ergebnisse: Die klinischen Parameter zeigen sowohl durch die konservative als auch durch die antibiotisch adjuvante Therapie eine signifikante klinische Verbesserung (p / Background: Several studies have shown a therapeutical benefit from systemic antibiotics in the treatment of severe periodontitis. However, it has not yet been layed down which concept of antibiotic treatment is the best. Therefore the purpose of this study is to compare two different systemic antibiotics adjunctive to a conventional, mechanical treatment of patients with rapidly progressive periodontitis (RPP) in a randomised, blinded, clinical trial. Material and methods: 33 patients with a clinically and radiographically confirmed diagnosis of RPP were distributed in two groups: (1) AM-group (n=17): 500 mg amoxicillin and 250 mg metronidazole (3*/ d - 10days), (2) D-group (=16) 200mg doxycyclin on the 1st day and 100mg doxycyclin for 13days. In the beginning the patients received 3* professional tooth cleaning, and subsequently scaling and root planning under local anaesthesia in two sessions. 3 months later a recall visit and the antibiotic regimen were carried out. In 3 months-intervals another 2 recall visits were performed. After successfull oral hygiene instructions and during all recall visits all clinical parameters like pocket depths, relative attachment level, and bleeding and pus on probing were evaluated with the Florida probe. The determination of 8 different periodontal pathogens was performed with the DNS-Sondentest of Meridol. Before the antibiotic treatment and during the following recall visits the microbiological samples were taken from the 4 deepest pockets with sterile paper points and analysed by PCR-technique in the laboratory of Wybert GmbH elmex Forschung, Lörrach. To determine the IL-1 genetic polymorphism venous blood samples were taken in the first session. The analysis was done by GenoType(R), PRTest (Hain Diagnostika GmbH). Results: The clinical parameters show a significant clinical improve by the conservative as well as by the adjunctive antibiotic treatment (p

Made available in DSpace on 2016-04-26T18:15:21Z (GMT). No. of bitstreams: 1 Patricia Assuf Nechar.pdf: 10906984 bytes, checksum: 97da991672c8c278888afe1f3880ac7a (MD5) Previous issue date: 2015-11-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The purpose of this Master s thesis is to study the social media s discourses regarding the fat body, especially those circulating in blogs associated with the plus size universe. Inserted in the field of communication and following the processes of creation in media and culture line of research, this study focuses on mapping out and conducting a critical analysis of the processes of creating and building a body image that questions and subverts the hegemonic representations and discourses. Nowadays, the body is a frequent object of discussion in the media. Two types of discourses prevail: in the mass media, the discourse takes on an imperative note, preaching the importance of having a perfect body. In the digital media, however, it is possible to notice the emergence of a counter discourse that defends other types of bodies, which escape the rules that govern the ideal body . This Master s thesis aims to map out the multiplicity of images and discourses emerging in the cyberspace. The concept of cyberspace adopted was the one defined by Leão: a gigantic, almost endless maze of interactions typical of contemporary times, a network composed of hardware, software, people and groups. The research focuses on the following topics of discussion: daily life, body acceptance, fashion, health, self-esteem, prejudice, and respect. The theoretical frameworks adopted were: process analysis and criticism theories (Salles and Leão); body, image and power (Foucault); social networks (Costa); communication devices (Prado); body images (Sant Anna, Ortega and Vigarello). The methodology consisted of literature review; identification, selection and analysis of documents published in the social networks included in the study; image research (iconology) associated with art projects related to the concept of obese bodies; and mapping of images and imaginary as a method of knowledge production (Leão). Grounded in the idea of image, talk spaces and power (Foucault), the research shows the importance of building an imaginary. Through the analysis of documents published in these networks (photographs, records of discussions, among others), it was possible to map out the complexities of the issues involving the authors and groups in the plus size universe. Among the findings, the mapping of images and discourses conducted in this research shows that the creation of an alternative, subversive and politically engaged imaginary is essential to promote the freedom of expression and communication regarding the body that does not conform to established standards / Esta dissertação de mestrado tem como objeto de estudo os discursos das redes sociais em relação ao corpo gordo, em especial, aqueles que circulam no ciberespaço, nos blogs do universo Plus Size. Inserida no campo da comunicação, na linha de pesquisa processos de criação nas mídias e na cultura, nossa pesquisa tem como foco o mapeamento e análise crítica dos processos de criação e construção de uma imagem do corpo que problematiza e subverte as representações e os discursos hegemônicos. Atualmente, o corpo é objeto de discussão frequente no universo das mídias. Observa-se a predominância de dois tipos de discursos: nas mídias de massa, os discursos assumem um caráter imperativo e pregam a valoração de um corpo ideal. Nas mídias digitais, no entanto, é possível observar a emergência de um contra-discurso que defende a valoração de outros tipos de corpos que fogem às normatizações que regem o corpo ideal. Nesse contexto, esta dissertação de mestrado tem como objetivo cartografar as imagens e discursos que emergem no ciberespaço, em suas multiplicidades. Entende-se o conceito de ciberespaço tal como foi definido por Leão: um labirinto gigantesco e quase-infinito de interações da era contemporânea, uma rede composta por hardwares, softwares, pessoas e grupos. Entre os temas que circulam nas discussões elencamos: cotidiano, aceitação do corpo, moda, saúde, autoestima, preconceito e respeito. A pesquisa tem como referencial teórico: teorias de análise e crítica de processos (Salles e Leão); corpo, imagem e poder (Foucault); redes sociais (Costa); dispositivos comunicacionais (Prado); imagens do corpo (Sant Anna, Ortega e Vigarello). A metodologia é composta por revisão bibliográfica; coleta, seleção e análise de documentos das redes sociais elencadas; pesquisa imagens (iconologia) vinculada a projetos artísticos que se relacionam com o conceito de corpos obesos; e cartografia de imagens e imaginários como método de produção de conhecimento (Leão). Fundamentada na ideia de imagem, espaços de conversações e poder (Foucault), a pesquisa demonstra a importância da construção de um imaginário. Através da análise dos documentos que circulam nessas redes (imagens fotográficas, registros de discussões em rede, entre outros) foi possível mapear as complexidades das questões de natureza relacional que constituem os autores e os grupos do universo plus size. Entre os resultados alcançados, a cartografia de imagens e discursos desenvolvida em nossa pesquisa demonstra que a criação de um imaginário alternativo, subversivo e politicamente engajado é fundamental na valoração aos direitos de expressão e comunicação vinculados ao corpo situado fora dos padrões estabelecidos

Substantial research on the functionality of athletic apparel has been conducted; however little consideration has been given to the plus size figure. Societal messages suggest that overweight women are lazy and therefore would not be interested in athletic apparel. The purpose of this study was to determine overweight adult women's experience with athletic clothing. The sample consisted of 14 women, ages 30 to 65 who wore size 1X to 3X. They were each supplied with a Nike brand athletic outfit and participated in two in depth interviews. Data collection methods included qualitative interviews, quantitative surveys and guided journaling. The major findings suggest that overweight women have difficulty shopping for clothing. Difficulty and frustration was experienced on a number of levels including; limited stores, limited selection and styles, fitting issues, over-priced items and less color options compared to smaller sizes. The findings suggest overweight women experience emotional anxiety when trying on clothing for the first time. Dissatisfaction with clothing fit was attributed to the belief their body is unsuitable and needs to change. Satisfaction with clothing fit was attributed to the ability of the apparel designer. Many negative experiences have left this sample feeling disappointed and marginalized. Some participant's experienced increased desire to participate in physical activity while others felt exercise was a necessity regardless of the clothing available. By trying on the Nike brand clothing, it gave the women in this study an alternative way of dressing themselves which has enabled several women to feel differently about their size and their body in athletic clothing. The current sample showed behaviors of internalization by using dehumanizing terms to describe body parts. The sample felt discriminated against in the media and wanted to see larger women modeling clothing. Apparel companies should include a wider variety of sizes in their brick and mortar stores as to not alienate a population. Apparel companies should incorporate diverse models into advertisement to include the plus-size population. Proving high quality athletic apparel to plus size women provided an opportunity for them to experience their bodies in a new perspective. Future studies should develop new pattern making, grading and sizing techniques in order to provide better fitting athletic apparel for large size bodies. Studies expanding on fit and comfort of athletic apparel for large bodies should be explored. This paper provides an initial indication of how plus size women experience athletic apparel. Further understanding of clothing, fit and exercise behavior are needed. / Graduation date: 2013 / Access restricted to the OSU Community at author's request from July 18, 2012 - January 18, 2013

Le Network Calculus est une théorie visant à calculer des bornes pire-cas sur les performances des réseaux de communication. Le réseau est modélisé par un graphe orienté où les noeuds représentent des serveurs, et les flux traversant le réseau doivent suivre les arcs. S'ajoutent à cela des contraintes sur les courbes de trafic (la quantité de données passées par un point depuis la mise en route du réseau) et sur les courbes de service (la quantité de travail fournie par chaque serveur). Pour borner les performances pire-cas, comme la charge en différents points ou les délais de bout en bout, ces enveloppes sont combinées à l'aide d'opérateurs issus notamment des algèbres tropicales : min, +, convolution-(min, +)... Cette thèse est centrée sur l'algorithmique du Network Calculus, à savoir comment rendre effectif ce formalisme. Ce travail nous a amené d'abord à comparer les variations présentes dans la littérature sur les modèles utilisés, révélant des équivalences d'expressivité comme entre le Real-Time Calculus et le Network Calculus. Dans un deuxième temps, nous avons proposé un nouvel opérateur (min, +) pour traiter le calcul de performances en présence d'agrégation de flux, et nous avons étudié le cas des réseaux sans dépendances cycliques sur les flux et avec politique de service quelconque. Nous avons montré la difficulté algorithmique d'obtenir précisément les pires cas, mais nous avons aussi fourni une nouvelle heuristique pour les calculer. Elle s'avère de complexité polynomiale dans des cas intéressants. / Network Calculus is a theory aiming at computing worst-case bounds on performances in communication networks. The network is usually modelled by a digraph : the servers are located on the nodes and the flows must follow path in the digraph. There are constraints on the trafic curves (how much data have been through a given point since the activation of the network) and on the service curves (how much work each server may provide). To derive bounds on the worst-case performances, as the backlog or the end-to-end delay, these envelopes are combined thanks to tropical algebra operators: min, +, convolution... This thesis focuses on Network Calculus algorithmics, that is how effective is this formalism. This work led us to compare various models in the litterature, and to show expressiveness equivalence between Real-Time Calculus and Network Calculus. Then, we suggested a new (min, +) operator to compute performances bounds in networks with agregated flows and we studied feed-forward networks under blind multiplexing. We showed the difficulty to compute these bounds, but we gave an heuristic, which is polynomial for interesting cases.

Orientador: Rubens Maciel Filho / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-23T11:34:50Z (GMT). No. of bitstreams: 1 Maia_JulioPereira_D.pdf: 8705466 bytes, checksum: e604d7a471ca19eb99492912d431174b (MD5) Previous issue date: 2013 / Resumo: Esta tese apresenta um estudo de estratégias de esquemas de controle em unidades de destilação a vácuo de refinarias de petróleo, com o uso de dados e informações de uma refinaria brasileira, de modo a se desenvolver uma simulação representativa do processo, onde uma diferença global máxima de 5% entre os resultados de simulação e os dados de saída reais foi obtida. A simulação foi executada com alto nível de detalhamento, com cálculos de queda de pressão, dimensionamento de sistemas de bombeamento e uso de internos de coluna comerciais. Uma análise paramétrica foi executada para a verificação das variáveis mais influentes do processo. A simulação em estado estacionário resultante foi então convertida para o regime dinâmico, onde um esquema de controle equivalente ao esquema de controle da planta real foi implementado. Este esquema de controle foi submetido a um conjunto de perturbações usuais ao processo real, produzindo respostas dinâmicas do processo para cada perturbação aplicada. Pela análise das dinâmicas destas respostas e das respostas do sistema em malha aberta, um esquema de controle alternativo foi proposto e verificado da mesma maneira que o esquema de controle equivalente. Malhas de controle específicas para quantificar a qualidade dos produtos, tendo por base o índice ASTM D86 foram inseridas. A comparação entre os dois esquemas de controle por meio das respostas dinâmicas na qualidade dos produtos, considerando como parâmetro o ISE (Integral Squared Error) das malhas de cada esquema para comparação, apresentou uma redução média do erro em 70% na qualidade dos produtos principais / Abstract: A petroleum vacuum distillation unit study on control scheme strategies is developed in this work. Real plant data and information is gathered from a Brazilian Refinery to develop a representative simulation of the process, which had achieved a maximum 5% overall difference from the plant results. The simulation was set to be highly detailed, including pressure drop calculations, pumping system and the use of commercial column internals (packing and plates) in it. A parametric analysis was carried in order to verify the most influent variables in the process, with respect to temperature profiles, product flows and product qualities. The resultant steady state simulation was then converted into dynamic regime, when a control scheme equivalent to the real plant control scheme was implemented. This control scheme was then subjected to a set of common perturbations that occur in the real process, producing the dynamic response of the process to each perturbation applied. By analyzing the dynamics of these responses and the open loop responses, an alternative control scheme is proposed and verified in the same manner the later one was. A specific control loop was proposed to account a petroleum product quality index, such as ASTM D86 95% recovery. The comparison of the control schemes by means of the dynamic responses considering the correlated ISE (integral squared error) of each scheme has shown an average error reduction of 70% in the main products quality / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química

This thesis is following up a concept of diversity management, in great detail we are talking here about age management, which is human resources management with respect to age and ability of the employee. The theoretical part deals with management of diversity in work teams, defines age management as the possibility of adapting the organization to the needs of aging employees. Highlights the demographic development of the society, bringing us near to age spread of the teachers in schools in the Czech Republic. The empirical part describes in detail the age management tools as suitable instrument for adapting the working conditions for the employees of age 50+. It contains three sub-surveys in three kindergartens, three Primary Schools and three Elementary Art Schools in Prague. Based on semi-structured interviews with the directors and also on answering questionnaires about the age management and the utilization of its tools in between the group of pedagogues of age 50+ and the group of operational staff of age 50+ at the surveyed schools compares the possibility of introducing the instruments of the age management to schools with needs of employees of age 50+. The aim of this work is to describe and compare the current state of use of the age management elements in kindergartens, Primary Schools...

[pt] Injeção de dependências, uma forma de inversão de controle, é uma forma de estruturar a configuração e composição de componentes de software que traz vários benefícios como um acoplamento reduzido entre componentes. No entanto, um framework genérico de injeção de dependências requer instrospecção em tempo de execução, o que explica por que injeção de dependências é popular em Java mas praticamente inexistente em C Mais Mais. Neste trabalho apresentamos um sistema de introspecção para C Mais Mais 11 e mostramos como ele pode ser usado para melhorar uma implementação de Service Component Architecture (SCA) para C Mais Mais. Usamos vários novas funcionalidades de C Mais Mais 11 como perfect forwarding, variadic templates e lvalue references para melhorar a usabilidade da API de reflexão e minimizar o overhead de execução. / [en] Dependency injection, a form of inversion of control, is a way of structuring the configuration and composition of software components that brings many benefits such as a loose coupling of components. However, a generic dependency injection framework requires runtime type introspection and this is why dependency injection is popular in Java and almost non-existent in C plus plus. In this work we present a introspection system for C plus plus 11 and show how to use it to improve an implementation of the Service Component Architecture (SCA) for C plus plus. It uses several features of C plus plus 11 such as perfect forwarding, variadic templates and lvalue references to improve usability and minimize overhead.

Le développement du bois énergie est un des principaux leviers dans la lutte contre le changement climatique. Cependant son utilisation à grande échelle n’est pas sans risque pour l’environnement. Afin de quantifier les impacts environnementaux de la filière bois énergie, nous avons, dans un premier temps, développé un modèle systémique de la filière, depuis la forêt jusqu’à la production d’énergie. Deux technologies ont été considérées pour la co-production d’électricité et de chaleur à partir de biomasse forestière : l’une, traditionnelle, par combustion directe, et l’autre, plus avancée mais moins mature, par gazéification. Dans le cas de la gazéification, nous avons défini les conditions opératoires les plus favorables du procédé en tenant compte des rendements énergétiques et exergétiques ainsi que de la qualité du syngas. Dans un deuxième temps, nous avons calculé les flux de carbone et de minéraux exportés lors de la récolte du bois ainsi que le nombre d’hectares requis, puis les ressources et rejets liées au fonctionnement des centrales biomasses. Nous avons noté qu’une intensification des pratiques sylvicoles résultait en une augmentation des exportations de minéraux. Enfin, nous avons évalué les performances environnementales des deux filières à l’aide d’une Analyse de Cycle de Vie (ACV). Dans le contexte énergétique français, les deux systèmes offrent des performances très similaires, avec un léger avantage à la combustion. Du point de vue du changement climatique, il serait plus particulièrement bénéfique de développer ces procédés biomasse afin de remplacer les technologies de production d’énergie basées sur les combustibles fossiles / Biomass is one of the most promising renewable energy source in Europe. Its use as a substitute to fossil energy is expected to mitigate climate change. However, potential drawbacks are also feared with large scale development. In order to assess the environmental impacts of the biomass-to-energy chain, we firstly developed a model of the bioenergy system, from the forest to the energy production. We focused on two biomass power plants for combined heat and power (CHP) production: one is based on the conventional direct combustion process while the other is based on the more advanced gasification process. Gasification offers higher electrical efficiency, but its development is still facing technical difficulties. In case of the gasification process, we defined the best operating conditions regarding energetic and exergetic efficiencies, as well as the syngas quality requirements. Secondly, we calculated the carbon and mineral flows taken from the forest through energy wood harvesting, along with the forested area required to feed the CHP plant. The other resources and emissions related to the plant operation were also predicted. We observed that more extensive forestry practices led to an increase in the mineral exports. Finally, we evaluated the environmental performance of the two biomass CHP plants using life cycle assessment (LCA). Within French energy context, we found that both CHP technologies had very similar impacts with a slight advantage toward the combustion process. It appears of particular benefit to replace current fossil energy systems with biomass CHP plants to reduce climate change

Ce travail de recherche porte sur la modélisation mathématique des principaux procédés sidérurgiques en suivant une approche systémique. L’objectif est d’élaborer un outil de modélisation de l’ensemble de la filière destiné à l’optimiser du point de vue énergétique et environnemental. Nous avons développé des modèles physico-chimiques du haut fourneau, de la cokerie, de l’agglomération et du convertisseur. Ces modèles ont ensuite été reliés entre eux sous forme d’un diagramme de flux unique en utilisant le logiciel ASPEN Plus. Dans une première partie, nous nous sommes particulièrement intéressés au haut fourneau à recyclage, une variante innovante du haut fourneau dans laquelle les gaz de gueulard sont recyclés et réinjectés aux tuyères après capture du CO2. Nous avons testé une réinjection à un niveau (aux tuyères) et à deux niveaux (tuyères et ventre). Les résultats ont été comparés avec succès à des données expérimentales issues d’un réacteur pilote et montrent que le recyclage permet une baisse de plus de 20 % des émissions de CO2 du haut fourneau. Le recyclage à deux niveaux ne semble pas plus performant que celui à un seul niveau. Dans un deuxième temps, nous avons simulé le fonctionnement d’une usine sidérurgique intégrée dans son ensemble. Différentes configurations ont été testées, pour un haut fourneau classique ou un haut fourneau à recyclage, en considérant un éventuel recyclage du laitier de convertisseur à l’agglomération, et en étudiant l’influence de la teneur en silicium de la fonte sur toute la filière. On montre notamment qu’il est possible de réduire le prix de revient de la tonne d’acier en substituant et recyclant différents sous-produits / This research study deals with mathematical modeling of the main steelmaking processes following a systems approach. The objective was to build a modeling tool of the whole steelmaking route devoted to its energetic and environmental optimization. We developed physical-chemical models for the blast furnace, the coke oven, the sintering plant and the basic oxygen furnace. These models were then linked together in a single flow sheet using the ASPEN Plus software. First, we focused on the top gas recycling blast furnace, a novel variant of the blast furnace in which the top gas is recycled and re-injected into the tuyeres after CO2 removal and capture. We tested both a reinjection at one level (tuyeres only) and at two levels (tuyeres and shaft). The results were successfully compared with experimental data from a pilot reactor and demonstrate that recycling can lower the blast furnace CO2 emissions by more than 20%. Recycling at two levels does not seem more efficient than at a single level. Second, we simulated the operation of an entire integrated steelmaking plant. Different configurations were tested, using a conventional blast furnace or a top gas recycling blast furnace, considering a possible recycling of the converter slag to the sintering plant, and studying the influence of Si content in the hot metal on the entire steelmaking plant operation. We show that it is possible to reduce the cost of producing steel by substituting and recycling various by-products