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Fatores produtivos e industriais que interferem na qualidade da carne bovina /Ferreira, Maurício Manduca. January 2004 (has links)
Resumo: Devido inúmeras alterações ocorridas no mercado consumidor de carne bovina, tornou-se necessário à evolução do mercado de carne bovina de qualidade. Objetivando tais mudanças, foram estabelecidos os fatores produtivos e industriais que influenciam os padrões de qualidade da carne bovina. A pesquisa de campo foi desenvolvida nas regiões de Barretos, Ribeirão Preto e São José do Rio Preto (SP) e teve início com a definição dos frigoríficos pelo Serviço de Inspeção de Produtos de Origem Animal, que estavam estabelecidos nas regiões acima citadas. Foram identificados seis frigoríficos nas três regiões e aplicados questionários objetivando o levantamento dos procedimentos e tecnologias adotadas nos processos que influenciam direta ou indiretamente os fatores relacionados à qualidade da carne bovina. Após esta etapa foram entrevistados os produtores, obtendo informações relacionadas aos processos e tecnologias adotadas pelo setor para os fatores da qualidade. Para análise estatística, foi utilizada a metodologia da Análise de Correspondência Simples. Como conclusão deste trabalho de pesquisa verificou-se a falha existente na cadeia produtiva da carne de qualidade, já que os dois elos mais importantes, acabam adotando estratégias que tornam o processo produtivo e industrial bastante heterogêneo, criando desta forma, empecilhos ao crescimento do setor. / Abstracts: Dune to numberless change occurred in the consumption market of bovine meat became necessary the evolution of the market of the quality of the bovine meat. To materialize that change, was established the products factors and the industrials that influence the standard of the quality of the bovine meet. The camp search was developed around Barretos, Ribeirão Preto and São José do Rio Preto (SP) and had beginning with definition of the meet industry by Animal Products Inspection Service, that was established and the mentioned area. It was identified six meat industry in the three areas and applied questionnaires objecting the procedures and technology survey adapted in the process and the adapted technologies in the process that influence direct or indirect on the related factors by the bovine meet quality. After this step was interviewed the producer, obtained information related to process and technologies adapted by the sector for the quality factor. For the statistic analysis, was utilized the methodology of "Analysis of Simple Correspondence". The conclusion of this search work it was checked the fail existent in the quality of meet production line, them the two most important link, ended adapting strategy that become the production process and industrial a quite like heterogeneous, creating in this farm, impediments for the growth of the sector. / Orientador: José Jorge Gebara / Coorientador: José Gilberto de Souza / Banca: Manoel Antonio de Almeida Monteiro / Banca: João Luiz Cardoso / Mestre
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Aplicações de cargas minerais em polímeros. / Application of minerals fillers in polymers.Antônio Bastos Torres Lima 21 March 2007 (has links)
As cargas minerais têm sido utilizadas em misturas com os mais variados tipos de polímeros, misturas estas chamadas compósitos, com a finalidade de barateamento de custos e, mais particularmente, porque agregam melhorias das características físicas e químicas das peças fabricadas. As indústrias químicas fabricantes de polímeros têm procurado desenvolver novos tipos de polímeros. A disputa torna-se acirrada pelo grande mercado consumidor que existe. As empresas tentam, então, atender as mais diversas necessidades de tipos e características físicas e químicas dos materiais e peças fabricados pelas indústrias consumidoras. No Brasil as cargas minerais ainda são utilizadas pelas indústrias, na sua maioria, de forma empírica, em misturas com os polímeros. O entendimento das propriedades intrínsecas das cargas minerais e dos polímeros, da influência da tensão superficial na interação entre eles, o desenvolvimento de novos equipamentos de medida da tensão superficial, o desenvolvimento de agentes de tratamento superficial visando melhorar a compatibilidade de energia entre a carga mineral e o polímero, tudo isso tem contribuído para uma melhor compreensão e previsão das propriedades de compósitos e nanocompósitos. Várias pesquisas têm sido desenvolvidas nesta direção, cujo intuito principal é o de comparar o efeito do uso, em polímeros, de cargas minerais diversas, tratadas e não tratadas superficialmente com agentes químicos como silanos e ácidos graxos. As características físicas e químicas dos produtos destas misturas, como elongamento, tensão de ruptura à flexão, deformações ao calor, etc, são medidas e definidas, constatando-se modificações nestas propriedades quando comparadas com as mesmas propriedades para os polímeros puros. / The mineral fillers have been used in admixtures with a large variety of polymers called composites with the purpose not only of reducing their prices but mainly due to the improvements of their physical and chemical characteristics. The polymer manufacturers have been looking for the development of new types of polymers and composites in a battle driven by the great existing market as well as the consumers needs for products with distinct physical and chemical properties and lower prices. In Brazil the mineral fillers are still mainly used in empirical admixtures with polymers. The understanding of the intrinsic properties of mineral fillers and polymers, the influence of the surface tensions in the mineral/polymer interactions, the development of new equipments for measuring the surface tension, as well as chemical agents to promote the surface compatibility between mineral and polymer, has contributed for a better understanding and foreseeing the properties of composites and nanocomposites. Many researches have been developed under this direction with the goal of comparing the effect of using mineral fillers with and without superficial treatment by by chemical agents in admixed with polymers. The physical and chemical properties of these composites, such as elongation, flexural tensile strength, heating behavior and many others are measured and defined, supporting the properties enhancement when compared with the same properties for the stand alone polymers.
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Coupled photochemical-biological system to treat biorecalcitrant wastewatersBacardit Peñarroya, Jordi 06 July 2007 (has links)
Advanced Oxidation Processes (AOPs) are suitable for achieving the complete mineralization of organic pollutants in wastewaters, since they are based on the generation of a powerful non-selective chemical oxidant. A major drawback of AOPs is that they involve high operating costs if high levels of mineralization are endeavoured. Integration of an AOP with a biological treatment has demonstrated to be a suitable alternative, since it combines the capacity of the AOP, in this case Photo-Fenton, to enhance biodegradability, with a biological treatment such as a Sequencing Batch Biofilter Reactor (SBBR), which operating costs are lower.Photo-Fenton (Ph-F) process is carried out by irradiating the system with ultraviolet (UV) and/or visible (Vis) light. In Fenton processes, by combination of hydrogen peroxide (H2O2) as a reagent and iron ions (Fe2+ for example) as catalyst in acid medium, highly oxidant species are generated.According to the results, most of the studied parameters may be written as a function of [H2O2]0, which means that temperature and [Fe2+]0 do not affect significantly the results. Moreover, a subsequent scale-up of the process shows that degradation follow very similar tendencies and shows similar results.It has been observed that the efficiency of oxidation follows a tendency directly related to the amount of H2O2 applied. An innovative description of the process is their modelling regarding the evolution of COD and BOD5 over the oxidation process or depending on the amount of H2O2 applied. The models show good fitting properties, and they appear to be a good basis for more precise modelling of the system.Regarding the integration of both processes, the best operating conditions consists of first treating the solution by Ph-F with 500 mg.L-1 of [H2O2]0 and 10 mg.L-1 of [Fe2+]0 at 27 ºC. The resulting product is then treated in the SBBR for 8 hours of time. More than 90 % of mineralization is achieved. The bioreactor show high resistance when is exposed to toxic shock load. Concerning control possibilities, monitoring the Oxygen Uptake Rate (OUR) by in-situ respirometry is suggested to be a good parameter, since it is a direct measurement of bacterial activity.
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Sistemas de ayuda a la modelización de la producción en la empresa agrariaClop i Gallart, Maria Mercè 28 June 2000 (has links)
En els propers anys s'emprendrà el desenvolupament de sistemes d'ajut a la presa de decisions(SATD) que aconsellin els agricultors en la programació en condicions de risc i d'incertesa. Aquesta és una qüestió amplament examinada dins l'Economia Agrària, on s'han realitzat importants avenços. és per això que, en el Capítol 1, s'han revisat els principals corrents teòrics i els models proposats, per tal de fer balanç de les opcions disponibles, dels supòsits implícits, dels principals problemes i de les exigències deprogramació Possiblement, per als objectius als que pretèn contribuir aquesta Tesi Doctoral, la principal conclusió de la revisió sigui que les majors necessitats de desenvolupament són conceptuals, donat què una integració de la programació lineal i dels simuladors aleatoris (com la que hem desenvolupat a l'Annex 9), permet disposar d' un nucli de càlcul suficient.En molts casos la funció de densitat de probabilitat (f.d.p.) de les variables aleatòries dels models no només serà desconeguda, sinó que serà impossible determinar-la o no tindrà interés pràctic plantejar aquesta tasca, per la qual cosa la programació s'haurà de realitzar amb probabilitats subjectives, en un context estadístic baiesià. En la literatura econòmica agrària els estudis sobre determinació deprobabilitats subjectives no han estat massa nombrosos, per la qual cosa hi ha una necessitatd'experimentació en aquesta àrea d'activitat científica. És per això que, en el Capítol 2, s'hi han revisat les principals línies de desenvolupament de la Teoria Personalista de la Probabilitat, i en relació més directa amb els objectius immediats de la investigació, les principals conclusions al voltant de la forma deles f.d.p. de rendiments de cultius i l'estimació subjectiva d'aquelles funcions.Un programa que obtingui la informació mitjançant preguntes a un o diversos éssers humans, hade tenir en compte la tendència dels subjectes a cometre errors o biaixos sistemàtics, permanents idifícilment corregibles (si és que és possible la correcció, existint amplíssima evidència empíricacontrària). Aquest tema ha estat escassament tractat a la literatura econòmica, per la qual cosa en el Capítol 3 s'hi han revisat les principals formulacions, desenvolupades a la Psicologia.A partir del Capítol 4 s'ha discutit el treball experimental, que ha consistit a la realització dediverses enquestes: a experts en àmbits propers a la Fitotècnia; a un grup de deu agricultors, entrevistats en profunditat; i a un grup ampli d'agricultors. Les enquestes tractaven d'identificar problemes en els mètodes d'estimació de funcions de densitat de probabilitats de rendiments de cultius a partir de la informació subjectiva dels subjectes.En el Capítol 4 s'hi han discutit els problemes trobats en la investigació i, sobretot, els principals resultats de la mateixa, per tal de subratllar l'objectiu principal de la investigació és una exploració molt bàsica sobre problemes d'interpretació en els diferents mètodes d'estimació de les f.d.p. mitjançantinterrogació a subjectes, que pretèn identificar problemes i conjectures abans que obtenir conclusions.Els mètodes estudiats d'estimació de la f.d.p. són: (1) estimacions puntuals dels rendimentsmínims, més freqüents i màxims; (2) atribució de freqüències a intervals ordinals (llenguatge natural); i (3) traducció directa a una escala numèrica. Els resultats més interessants estan relacionats amb: (a)estimació coherent de valors mitjans amb l'aproximació beta-PERT, superior a la triangular, i possiblement dels recorreguts i de la forma de la f.d.p.; (b) coherència i bona estimació de la forma de les f.d.p. en escales ordinals; (c) dificultats d'interpretació de les escales ordinals (que s'entenen en els seussignificats materials abans que en la seva funció en la descripció d'intervals), i dificultat en la traducció a escales numèriques, especialment dels rendiments extrems; (d) en general, una descripció suficient coherent de les f.d.p. en relació a l'escassa sofisticació dels mètodes emprats; i (e) possibles biaixos en direccions contràries dels mètodes que utilitzen escales ordinals i numèriques. És important subratllar laconstatació de problemes relacionats amb els significats lingüístics.Els bons resultats experimentals obtinguts amb tècniques que poden considerar-se unaaproximació preliminar al problema central discutit, encoratgen a perfeccionar aquelles tècniques, per tal d'obtenir una metodologia d'obtenció d'informació dels subjectes que pugui utilitzar-se de forma eficaç en els SATD. / En los próximos años se emprenderá el desarrollo de sistemas de ayuda en la toma de decisiones(SATD) que aconsejen a los agricultores en la programación en condiciones de riesgo y deincertidumbre. Esta es una cuestión ampliamente examinada en la Economía Agraria, donde se hanrealizado importantes avances. Por ello, en el Capítulo 1, se han revisado las principales corrientes teóricas y los modelos propuestos, a fin de hacer balance de las opciones disponibles, de los supuestos implícitos, de los principales problemas y de las exigencias de programación. Posiblemente, para los objetivos a los que pretende contribuir esta Tesis Doctoral, la principal conclusión de la revisión sea quelas mayores necesidades de desarrollo son conceptuales, ya que una integración de la programación lineal y de los simuladores aleatorios (como la que hemos desarrollado en el Anejo 9), permite disponer de un núcleo de cálculo suficiente.En muchos casos la función de densidad de probabilidad (f.d.p.) de las variables aleatorias de los modelos no sólo será desconocida, sino que será imposible determinarla o no tendrá interés práctico plantear esa tarea, por lo que la programación se tendrá que realizar con probabilidades subjetivas, en un contexto estadístico bayesiano. En la literatura económica agraria los estudios sobre determinación deprobabilidades subjetivas no han sido muy numerosos, por lo que existe una gran necesidad deexperimentación en este área de actividad científica. Debido a ello, en el Capítulo 2, se han revisado las principales líneas de desarrollo de la Teoría Personalista de la Probabilidad, y en relación más directa con los objetivos inmediatos de la investigación, las principales conclusiones en torno a la forma de las f.d.p. de rendimientos de cultivos y la estimación subjetiva de esas funciones.Un programa que obtenga la información mediante preguntas a uno o varios seres humanos, debe tener en cuenta la tendencia de los sujetos a cometer errores o sesgos sistemáticos, permanentes ydifícilmente corregibles (si es que es posible la corrección, existiendo amplísima evidencia empírica contraria). Este tema ha sido escasamente tratado en la literatura económica, por lo que en el Capítulo 3 se han revisado las principales formulaciones, desarrolladas en la Sicología.A partir del Capítulo 4 se ha discutido el trabajo experimental, que ha consistido en la realización de diversas encuestas: a expertos en ámbitos próximos a la Fitotecnia; a un grupo de diezagricultores, entrevistados en profundidad; y a un amplio grupo de agricultores. Las encuestas trataban de identificar problemas en los métodos de estimación de funciones de densidad de probabilidades de rendimientos de cultivos a partir de la información subjetiva de los sujetos.En el capítulo 4 se han discutido los problemas encontrados en la investigación y, sobre todo, losprincipales resultados de la misma, a fin de subrayar el objetivo principal de la investigación: es una exploración muy básica sobre problemas de interpretación en los diferentes métodos de estimación de las f.d.p. mediante interrogación a sujetos, que pretende identificar problemas y conjeturas antes que obtenerconclusiones.Los métodos estudiados de estimación de la f.d.p. son: (1) estimaciones puntuales de losrendimientos mínimos, más frecuentes y máximos; (2) atribución de frecuencias a intervalos ordinales,(lenguaje natural); y (3) traducción directa a una escala numérica. Los resultados más interesantes tienen que ver con: (a) estimación coherente de valores medios con la aproximación beta-PERT, superior a la triangular, y posible contraste de los recorridos y de la forma de la f.d.p.; (b) coherencia y buena estimación de la forma de las f.d.p. en escalas ordinales; (c) dificultades de interpretación de las escalasordinales (que se entienden en sus significados materiales antes que en su función en la descripción de intervalos), y dificultad en la traducci�n a escalas numéricas, especialmente de los rendimientos extremos; (d) en general, una descripción suficiente coherente de las f.d.p., en relación a la escasa sofisticación de los métodos empleados; y (e) posibles sesgos en direcciones contrarias de los métodos que utilizan escalas ordinales y numéricas. Es importante subrayar la constatación de problemas relacionados con los significados lingüísticos.Los buenos resultados experimentales obtenidos con técnicas que pueden considerarse unaaproximación preliminar al problema central discutido, alientan a perfeccionar esas técnicas, a fin de obtener una metodología de obtención de información de los sujetos que pueda utilizarse de forma eficaz en los SATD. / The development of decision making support systems (SATD) will be undertaken in theforthcoming years, in order to advise farmers in programming for conditions of risk and uncertainty. This issue has been widely assessed in Agrarian Economy, and has had an important progress. This is why Chapter 1 contains a revision of the main theoretical trends and proposed models in order to make a balance of the available options, the implicit assumptions, the main problems and programming demands.According to the objectives this PhD Thesis envisages to contribute to, the main conclusion of the revision is that development needs may be essentially conceptual, since an integration of linear programming and random simulators (like the one developed in Annex 9) allows to have enoughcalculation nucleus.In many cases, the density function of probability (f.d.p.) of the models random variables willnot only be unknown, but also impossible to determine, or will be of no practical interest, then programming will have to be done with subjective probabilities in a Bayesian statistical context. In agrarian economic literature, studies on subjective probability determination have not been numerous, so there is a need for experimentation in this area of scientific activity. This is the reason why in Chapter 2,the main lines of development of the Personalistic Theory of Probability have been revised, andaccording to the most direct relation with the immediate research objectives, the main conclusions related to the crop yields f.d.p. shape and the subjective estimation of those functions.A program getting information out of questioning one or more individuals needs to take intoaccount the individuals tendency to commit permanent, systematic and difficult to correct mistakes or bias (if correction is possible when there is wide empirical evidence of the contrary). This issue has hardly been studied in economic literature, therefore, Chapter 3 contains a revision of its main formulations developed in Psychology.From Chapter 4 onwards, experimental work is discussed. It consisted of different surveys: tothe experts in fields related to Phytotechnics; a deeper survey to a group of ten farmers; and to anumerous group of farmers. The surveys sought to identify problems in the estimation methods of yield probability density functions out of the subjective information of the individuals.In Chapter 4 problems found in the research have been discussed, and, especially, the mainresults obtained, in order to emphasize the main objective of the research: that is a basic exploration ofthe interpretation problems in the different estimation methods of the f.d.p. by means of individuals questioning, that attempts to identify problems and conjectures than obtaining conclusions.The assessed methods of f.d.p. estimation are: (1) punctual estimations through minimum, mostfrequent, and maximum yields; (2) frequencies attribution to ordinary intervals (natural language); and (3) direct translation into a numerical scale. The most interesting results are related to: (a) a coherent estimation of average values with a beta - PERT approximation, superior to the triangular, and contrastpossible with f.d.p. ranges and shape; (b) coherence and good estimation of the f.d.p. shape in ordinal scales; (c) difficulties in interpreting ordinal scales (understood before in their material significance than in their function in describing intervals) , and difficulties in translation into numerical scales, specially ofextreme yields; (d) in general, a coherent sufficient description of f.d.p. in report to the little sophistication of the methods used; and (e) possible bias in opposite directions of the methods that use ordinal and numerical scales. The problems related to linguistic meanings are remarkable.The good experimental results obtained with techniques that can be considered as a preliminaryapproximation to the core problem discussed, are encouraging to perfect those techniques, so that amethodology for obtaining information out of the individuals that can be efficiently used in SATD can be achieved.
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Integration of knowledge-based, qualitative and numeric tools for real time dynamic systems supervisionMeléndez i Frigola, Joaquim 27 February 1998 (has links)
The proposal presented in this thesis is to provide designers of knowledge based supervisory systems of dynamic systems with a framework to facilitate their tasks avoiding interface problems among tools, data flow and management.The approach is thought to be useful to both control and process engineers in assisting their tasks. The use of AI technologies to diagnose and perform control loops and, of course, assist process supervisory tasks such as fault detection and diagnose, are in the scope of this work. Special effort has been put in integrationof tools for assisting expert supervisory systems design. With this aim the experience of Computer Aided Control Systems Design (CACSD) frameworkshave been analysed and used to design a Computer Aided Supervisory Systems (CASSD) framework. In this sense, some basic facilities are required to be available in this proposed framework:· / ion Tools, for signal processing,representation and analysis to obtain significative information.· To deal with process variables, measures or numerical estimations, and expert observations, with uncertainty and imprecision.· Expert knowledge representation at different levels by using a rule-based system or simple qualitative relations.· Modularity and encapsulation of data and knowledge would be useful for structuring information.· Graphical user interface to manage all those facilities in the same environment as actual CACSD packages.Several tools from the AI domain have been added as Simulink ToolBoxes to deal with abstracted information, qualitative relationship and rule-based ES. Simple and intuitive qualitative relationship can be implemented by means of ablock-based qualitative representation language called ALCMEN. An ES shell, called CEES, has also been embedded into MATLAB/Simulink as a block toallow modularisation and partition of large expert KBs. Finally, the numeric to qualitative interfaces is performed by a set of algorithms, called abstraction tools, encapsulated also in Simulink blocks. The functionality of the wholeframework is able due to the use of object oriented approach in the development and implementation of those tools.In this thesis an attempt is undertaken to make steps towards integration of tools for expert supervision, including once for qualitative and symbolic data representation and management and symbolic knowledge processing. The main research objectives of this work include the following points :1. Incorporation of object-variables into classical numerical data processing system. The aim is to allow structural qualitative and symbolic knowledge representation. Complex information is encapsulated in a single source/sink structure, called object-variable, providing methods for knowledge access and processing.2. Implementation of selected particular tools for qualitative and symbolic knowledge representation and interfacing. Higher abstract level information processing based on the introduced object-variables.3. Embedding an object oriented rule-based expert system into a classical CACSD framework in order to provide high level knowledge processing facilities based on the domain of expert knowledge, heuristics, and logic.The object approach forces engineers to structure knowledge becoming highly locatable, modular and encapsulated. This features are very important to getexpert supervisory system design closer to process. The objective is to approach design tools to process engineers avoiding extra-time in learning application functionality and interfacing process variables and design tools. Thus, objects are used in the process variables descriptions as sources of information, encapsulating tools to provide significant (qualitative or numerical) information. Object oriented features will permit to divide large KBs into smaller ones to deal with complex systems adopting distributed solutions. Consequently, ES becomes more specialised, maintainable, and easier to validate.
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Vendre la ville (post)industrielle. : Capitalisme, pouvoir et politiques d'image à Roubaix et à Sheffield (1945-2010) / Selling the (post)industrial city. : Capitalism, power and image policies in Roubaix and Sheffield (1945-2010).Rousseau, Max 23 September 2011 (has links)
Ce travail se penche sur la question suivante : pourquoi, dans des villes en difficulté, une part importante des ressources est-elle attribuée à des biens symboliques? A cette fin, la thèse s'intéresse à l'évolution des «politiques d'image» pour interpréter la mutation du pouvoir et des politiques urbaines depuis la seconde guerre mondiale. Ce travail se fonde sur l'étude approfondie de deux villes nées de l'industrie: Roubaix et Sheffield. La thèse propose ainsi d'affiner la grille économico-politique couramment utilisée par les études urbaines critiques en introduisant une périodisation en cinq temps. La première partie analyse l'apparition des politiques d'image dans les deux villes, au tournant des années 1960, comme reflétant un processus de « fordisation des politiques urbaines». Cette partie propose une division de l'ère fordiste en deux sous-périodes idéal-typiques, l'early urban fordism et le !ate urban fordism. Consacrée aux années où la désindustrialisation s'accélère, la deuxième partie met en lumière le rôle des mouvements sociaux dans l'évolution divergente des politiques d'image. Enfin, la troisième partie consacrée à « l'entrepreneurialisation des politiques urbaines» propose de subdiviser cette fois l'ère postfordisteen deux sous-périodes, l'early urban entrepreneuria!ism et le tate urban entrepreneurialism. L'évolution des politiques d'image, de leur production et de leurs cibles résulte conjointement de la poursuite du déclin de l'industrie dans la base économique des villes, de la fragmentation de la classe ouvrière et du rapprochement des gouvernements urbains avec les intérêts privés survenue dans les deux villes depuis la fin des années 1970. / This work addresses the following question: why, in cities in difficulty, is a significant share of resources allocated to symbolic goods? To this end, the thesis examines the evolution of the "image policies" to interpret the shift in urban power and policy since the Second World War. This work is based on a thorough study of two cities born of the industry: Roubaix and Sheffield. The thesis proposes to refine the chronological political economic analysis commonly used by critical urban studies by introducing a periodization in five steps. The first part analyses the emergence of image policies in both cities at the turn of the 1960s, as reflecting a process of "fordisation of the urban policy." This section proposes a division of the Fordist era into two ideal-typical periods, early urban Fordism and late urban Fordism. Devoted to the years when de-industrialization increases, thesecond part highlights the role of social movements in the divergent evolution of the political picture. The third section on "the entrepreneurialisation of urban policy" proposes to subdivide the post-Fordist era into two sub-periods, early urban entrepreneurialism and late urban entrepreneurialism. The evolution of image policies, of their production and their targets, jointlyresult in the decline of industry in the economic base of cities, the fragmentation of the working class and the closer cooperation of urban governments with interests private which occurred in both cities since the late 1970s.
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Filtro anaeróbio ascendente combinado com reator aeróbio de lodos ativados em batelada no tratamento de água residuária sintética de indústria de polpa celulósica não branqueada sob condições termofílicas / Upflow anaerobic filter combined with aerobic reactor of activated sludge in batch treating of synthetic wastewater from unbleached cellulose pulp plant under thermophilic conditionsMegda, Cláudia Regina 20 September 2007 (has links)
Um sistema combinado anaeróbio-aeróbio composto de um filtro anaeróbio ascendente seguido de reator aeróbio de lodos ativados em batelada, foi continuamente alimentado com água residuária sintética da indústria de polpa celulósica não branqueada, durante o período de trezentos e sessenta e três dias, com o objetivo de verificar o desempenho dos reatores operados sob condições termofílicas. Os reatores foram inoculados com lodo mesofílico com gradual adaptação para a condição termofílica e operados em duas fases distintas. A primeira e segunda fases contemplam os períodos em que os reatores foram operados em temperatura termofílica de 55 e 65 graus Celsius, respectivamente. O filtro anaeróbio trabalhou com tempo de detenção hidráulica de 48 horas em fluxo contínuo e o reator aeróbio operado em bateladas seqüenciais (RBS) com tempos de ciclo de 12, 18 e 24 horas. A melhor eficiênica de remoção de DQO do sistema combinado anaeróbio-aeróbio foi de 65%, devida, em maior parte ao reator anaeróbio. O filtro anaeróbio operado em temperatura de 55 e 65 graus demonstrou eficiência na capacidade de retenção de biomassa termofílica, evitando a perda no efluente. O RBS, quando operado em temperatura de 55 graus e tempo de ciclo de 18 horas, demonstrou melhor eficiência para pós-tratamento de água residuária sintética. Os resultados gerais mostram uma melhor eficiência dos reatores operados em temperatura de 55 graus Celsius. / A combined anaerobic-aerobic system, composed of an upflow anaerobic filter followed by an aerobic reactor of activated sludge in batch, was continuously feed with synthetic wastewater from unbleached cellulose pulp plant during a period of three hundred and sixty three days, aiming to verify the performance of the reactors operating under thermophilic conditions. The reactors were inoculated with mesophilic sludge having a gradual adaptation to the thermophilic condition and they were operated in two distinct phases. The first and second phases contemplate the periods in which the reactors were operated in a thermophilic temperature of 55 and 65 Celsius degrees, respectively. The anaerobic filter worked with hydraulic detention time of 48 hours in a continuous flow, and the aerobic reactor was operated in a sequencing batch (SBR) with a cycle time of 12, 18 and 24 hours. The best efficiency of the combined anaerobic-aerobic system to remove DQO was 65% due to, in most part, the anaerobic reactor. The anaerobic filter, operating in temperatures of 55 and 65 degrees, has demonstrated efficiency in the capacity to retain thermophilic biomass, avoiding effluent lost. The SBR reactor, when operated in temperature of 55 degrees and a cycle time of 18 hours, has demonstrated better efficiency in the post-treatment of synthetic wastewater. The general results have showed a better efficiency of the reactors operating in a thermophilic temperature of 55 Celsius degrees.
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Formulaciones de nuevos morteros y cementos especiales basadas en suproductos de magnesioFormosa Mitjans, Joan 03 December 2012 (has links)
Aquesta tesi conté una recerca amb possibilitat de generar una patent, que afecta a "Magnesitas Navarras S.A" / En la presente tesis doctoral se evalúa el potencial de algunos subproductos de magnesio empleados para la formulación de diferentes materiales de construcción y su utilización en diferentes soluciones constructivas. En este sentido, el uso de subproductos industriales para el desarrollo de materiales de construcción potencia criterios de sostenibilidad y beneficios medioambientales asociados a la reutilización de materiales secundarios y a la disminución de actividades extractivas de recursos naturales.
La memoria de la presente tesis doctoral se ha estructurado siguiendo el mismo eje conductor desarrollado en la parte experimental del trabajo. Así, ésta incluye una primera parte en la que se detalla el estado del arte referente a los materiales de construcción, así como las soluciones constructivas propuestas. Estas soluciones son, por un lado, el desarrollo de morteros destinados a la protección pasiva frente al fuego (PPF) y, por otro, la formulación de cementos químicos de fosfato (CBPC) de magnesio como material reparador de estructuras de hormigón.
Como primer punto del trabajo experimental se ha estudiado y caracterizado exhaustivamente los diferentes subproductos empleados, tanto físico-química como morfológicamente. Esta caracterización preliminar es de gran importancia en el desarrollo de la investigación, dado que, al tratarse de subproductos industriales, no se conocen de antemano las características y las propiedades que éstos presentan, siendo su conocimiento de vital importancia para la correcta consecución de los objetivos establecidos.
En el desarrollo experimental de la primera de las soluciones constructivas propuestas, se ha empleado dos subproductos de magnesio [Low-Grade Magnesium Hydroxide (LG-MH) y Low-Grade Magnesium Carbonate (LG-MC)] en la formulación de morteros PPF, utilizando en este caso el cemento Portland convencional como material aglomerante. Ambos subproductos industriales descomponen térmicamente mediante procesos endotérmicos que cubren un amplio rango de temperaturas, retardando así el tiempo necesario para alcanzar una determinada temperatura. En este caso, se han formulado morteros empleando como áridos distintos porcentajes de ambos subproductos, dando lugar a un material con buenas propiedades térmicas y mecánicas, factible de ser utilizado como un mortero PPF. Sin embargo, su utilización como mortero revoco puede verse limitada por la elevada densidad de los áridos utilizados. En este supuesto, puede mejorarse su aplicabilidad añadiendo a los morteros formulados con subproductos de magnesio un árido ligero, como la vermiculita, sin que ello perjudique al resto de propiedades evaluadas.
En la consecución de la segunda solución constructiva propuesta, se evalúa la viabilidad del uso como materia prima de otro subproducto de magnesio [Low-Grade Magnesium Oxide (LG-MgO)], en este caso para el desarrollo de cementos químicos de fosfato (CBPC) de magnesio. A tal efecto, se han determinado las propiedades mecánicas de distintas dosificaciones, así como el efecto de un aditivo retardante del fraguado, el ácido bórico (HB), descrito en la bibliografía como retardante de fraguado que permite mejorar la trabajabilidad de los CBPC. Este estudio se ha realizado empleando una herramienta estadística, el diseño de experimentos (DoE), con la finalidad de obtener modelos matemáticos que justifiquen las interacciones entre los distintos componentes de la mezcla y su efecto sobre las propiedades mecánicas y el tiempo de fraguado. Asimismo, el uso del DoE ha de permitir reducir el número de experimentos y establecer el mejor rango de dosificaciones en función de las características deseadas, dando lugar a una formulación adecuada para su utilización en las soluciones constructivas objeto de estudio. Destacar que el uso de LG-MgO en la formulación de CBPC introduce fases inertes no-reactivas contenidas en el propio subproducto, lo que implica que los CBPC desarrollados puedan considerarse como morteros.
A partir de los resultados obtenidos se ha seleccionado un pequeño grupo de formulaciones con porcentajes adecuados para evaluar su potencial empleo en el desarrollo de morteros reparadores de estructuras de hormigón. Con este propósito, se han realizado ensayos de adhesión sobre distintos sustratos (hormigón o terrazo) y se ha determinado algunas propiedades requeridas para su uso en la solución constructiva propuesta.
La presente tesis doctoral pretende confirmar la viabilidad tecnológica para los distintos campos de aplicación que se han postulado. Sin embargo, no es un objetivo de este estudio el desarrollar un producto final que pueda ser comercializado, sino demostrar su viabilidad gracias al know-how adquirido durante los años de esta investigación, y sentar así las bases para futuros estudios en el desarrollo de materiales de construcción empleando estos subproductos. / The present thesis is focused in the assessment of some magnesium by-products and their potential reutilization for the formulation of different materials for several construction applications. Therefore, the use of industrial by-products for the development of construction materials highlights the sustainability criteria along with the environmental benefits associated with the reutilization of secondary materials whilst diminishing the extractive activities of natural resources.
This thesis has been structured following the same pattern for the experimental work. Thus, the first part details the state of the art in what construction materials concerns as well as some of the construction solutions suggested. These solutions are, on the one hand, included in the development of mortars for passive fire protection (PFP) and, on the other hand, in the formulation of chemical bonded phosphate ceramics (CBPC) as a repairing material for concrete structures.
The first part presents an exhaustive chemical, physical and morphological characterization of the by-products used. This preliminary characterization is of great importance in the development of the research because of the industrial origin of these by-products.
In the first part of the experimental section, the first of the solutions proposed used two types of magnesium by-products [Low-Grade Magnesium Hydroxide (LG-MH) and Low-Grade Magnesium Carbonate (LG-MC)] in the formulation of PFP mortars, using conventional Portland cement as a binder. Both industrial by-products thermally decompose through endothermic processes in a wide range of temperatures, delaying the time needed to achieve a selected temperature. In this case, the mortars were formulated by using different percentages of both by-products as aggregates, obtaining a material with good thermal and mechanical properties and therefore feasible to be used as a PFP mortar. However, its utilization as a sprayed mortar can be limited because of the high density of the aggregates used. In this sense, the practical applicability can be improved by adding a lightweight aggregate such as vermiculite, without diminishing the rest of the assessed properties.
Subsequently, in the second part of the experimental section, the viability of another magnesium by-product [Low-Grade Magnesium Oxide (LG-MgO)] is evaluated. In this case, for the development of chemical bonded phosphate ceramics (CBPC). The assessment was made by determining the mechanical properties of different dosages as well as by measuring the effect of a setting-time retarder additive, boric acid (HB), described in the literature as a good additive for this purpose while improving workability as well. This study has been realized by means of a statistical method, the design of experiments (DoE), with the purpose of obtain mathematical models that justify the interactions between different components in the mix and their effect in the mechanical properties and the setting-time. Moreover, the use of DoE enables the reduction in the number of experiments and establishes the best range of dosages as a function of the desired characteristics, giving an optimized formulation to be used in the construction solutions that are object of study. It has to be emphasize that the use of LG-MgO in the formulation of CBPC introduces inert phases that are contained in the by-product itself and that are non-reactive, which implies that the CBPC obtained could be considered as mortars.
From the results obtained, a small group of formulations with different percentages was selected to be studied with respect their potential as repairing mortars in concrete structures. Following this objective, adhesion tests were performed over different substrates (concrete or terrazzo) and some of the properties required for their use were determined.
The main objective of this thesis is to confirm the technological viability for the different fields of application postulated. However, it is not the main purpose to develop a final product able to be commercialized but to prove the viability by means of the know-how acquired during the years of this research and setting up the base for future studies in the development of construction materials using these by-products.
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Especifica??o de um bloco funcional implementando rede neural para redes industriais foundations fieldbusBesch, G?udio Vin?cius Lopes 03 December 2004 (has links)
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Previous issue date: 2004-12-03 / This work proposes the specification of a new function block according to Foundation Fieldbus standards. The new block implements an artificial neural network, which may be useful in process control applications. The specification includes the definition of a main algorithm, that implements a neural network, as well as the description of some accessory functions, which provide safety characteristics to the block operation. Besides, it also describes the block attributes emphasizing its parameters, which constitute the block interfaces. Some experimental results, obtained from an artificial neural network implementation using actual standard functional blocks on a laboratorial FF network, are also shown, in order to demonstrate the possibility and also the convenience of integrating a neural network to Fieldbus devices / Esta disserta??o apresenta a especifica??o de um novo Bloco Funcional de acordo com o padr?o Foundation Fieldbus, implementando uma Rede Neural Artificial ?til em diversas aplica??es de controle de processos. Essa especifica??o inclui a defini??o do algoritmo central do bloco, que implementa uma RN, e das fun??es acess?rias de forma a prover seguran?a de opera??o, al?m da descri??o dos atributos do bloco, com ?nfase nos par?metros, que formam as interfaces do objeto. Apresentam-se tamb?m os experimentos que foram realizados a partir de uma rede FF de laborat?rio, em que se empregaram apenas blocos padronizados j? existentes, a fim de se verificar a possibilidade e a conveni?ncia de integra??o de algoritmos de RN em dispositivos de campo FF
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Filtro anaeróbio ascendente combinado com reator aeróbio de lodos ativados em batelada no tratamento de água residuária sintética de indústria de polpa celulósica não branqueada sob condições termofílicas / Upflow anaerobic filter combined with aerobic reactor of activated sludge in batch treating of synthetic wastewater from unbleached cellulose pulp plant under thermophilic conditionsCláudia Regina Megda 20 September 2007 (has links)
Um sistema combinado anaeróbio-aeróbio composto de um filtro anaeróbio ascendente seguido de reator aeróbio de lodos ativados em batelada, foi continuamente alimentado com água residuária sintética da indústria de polpa celulósica não branqueada, durante o período de trezentos e sessenta e três dias, com o objetivo de verificar o desempenho dos reatores operados sob condições termofílicas. Os reatores foram inoculados com lodo mesofílico com gradual adaptação para a condição termofílica e operados em duas fases distintas. A primeira e segunda fases contemplam os períodos em que os reatores foram operados em temperatura termofílica de 55 e 65 graus Celsius, respectivamente. O filtro anaeróbio trabalhou com tempo de detenção hidráulica de 48 horas em fluxo contínuo e o reator aeróbio operado em bateladas seqüenciais (RBS) com tempos de ciclo de 12, 18 e 24 horas. A melhor eficiênica de remoção de DQO do sistema combinado anaeróbio-aeróbio foi de 65%, devida, em maior parte ao reator anaeróbio. O filtro anaeróbio operado em temperatura de 55 e 65 graus demonstrou eficiência na capacidade de retenção de biomassa termofílica, evitando a perda no efluente. O RBS, quando operado em temperatura de 55 graus e tempo de ciclo de 18 horas, demonstrou melhor eficiência para pós-tratamento de água residuária sintética. Os resultados gerais mostram uma melhor eficiência dos reatores operados em temperatura de 55 graus Celsius. / A combined anaerobic-aerobic system, composed of an upflow anaerobic filter followed by an aerobic reactor of activated sludge in batch, was continuously feed with synthetic wastewater from unbleached cellulose pulp plant during a period of three hundred and sixty three days, aiming to verify the performance of the reactors operating under thermophilic conditions. The reactors were inoculated with mesophilic sludge having a gradual adaptation to the thermophilic condition and they were operated in two distinct phases. The first and second phases contemplate the periods in which the reactors were operated in a thermophilic temperature of 55 and 65 Celsius degrees, respectively. The anaerobic filter worked with hydraulic detention time of 48 hours in a continuous flow, and the aerobic reactor was operated in a sequencing batch (SBR) with a cycle time of 12, 18 and 24 hours. The best efficiency of the combined anaerobic-aerobic system to remove DQO was 65% due to, in most part, the anaerobic reactor. The anaerobic filter, operating in temperatures of 55 and 65 degrees, has demonstrated efficiency in the capacity to retain thermophilic biomass, avoiding effluent lost. The SBR reactor, when operated in temperature of 55 degrees and a cycle time of 18 hours, has demonstrated better efficiency in the post-treatment of synthetic wastewater. The general results have showed a better efficiency of the reactors operating in a thermophilic temperature of 55 Celsius degrees.
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