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Caracterização das águas de lavagem provenientes da etapa de purificação da produção de biodiesel de óleo de tilápia / Characteristics of rinse water from the purification step of the production of biodiesel oil tilapiaBraga, Erika de Almeida Sampaio 03 August 2012 (has links)
BRAGA, E. de A. S. Caracterização das águas de lavagem provenientes da etapa de purificação da produção de biodiesel de óleo de tilápia. 2012. 128 f. Tese (Doutorado em Engenharia Civil: Saneamento Ambiental) - Centro de Tecnologia, Universidade Federal do Ceará, Fortaleza, 2012. / Submitted by Marlene Sousa (mmarlene@ufc.br) on 2012-09-27T18:42:34Z
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Previous issue date: 2012-08-03 / Biodiesel is a fuel derived from renewable energy and considered environmentally friendly for being clean-burning. It means that it does not release into the atmosphere gases that contribute to the increasing of greenhouse effect. It is in fact, an option to replace petroleum fuels. The raw materials used to produce biodiesel may be either of vegetable or animal origins. Facing the dilemma of using vegetable raw materials for other purposes, such as food, the raw materials derived from animal fats, such as the oil extracted from fish viscera, appears as an interesting source of research for the use in biodiesel production. In the state of Ceará, the Castanhão dam has one of the largest farming areas of tilapia, a fish species that resists even in very polluted waters and therefore, is reproduced easily serving as food mainly in inner towns. Parallel to such advantage, there is the disadvantage of the fish viscera disposal. It is a fraction that has no use in soils and surface waters, causing serious environmental problems. Aiming to minimize the aforementioned problem, the association of the Castanhão dam fish farmers, in partnership with the Center for Industrial Technology Foundation of Ceará (NUTEC) started a research on the utilization of such visceral material in the biodiesel production. The research was carried out at the NUTEC and the production of biodiesel from viscera of tilapia has shown to have viability. However, during the process of biodiesel production, effluents are generated from high pollution loads due to the reagents used and the very composition of the raw material. Such effluents, called washing water originate from the step of purification of the biodiesel, the aqueous washing. The biodiesel obtained by a chemical reaction of transesterification, ie, fat (oil extracted from the viscera of tilapia), was transformed into an ester (biodiesel) in the presence of an alcohol (methanol) and a catalyst (sodium hydroxide). Then, the washing water from this step was characterized by physical-chemical analysis of parameters: pH, total ammonia, oxygen chemical demand (OCD), total phosphorus and methanol content, following the procedures in (APHA , 1998 and 2005) and (European Standard EN-14110/2001 - VARIAN). Comparing the results with the standards for effluent discharge of CONAMA Resolution nº 430, March 22nd, 2011, it was observed that the concentrations of the analyzed parameters were not in accordance with the aforementioned Federal Environmental Legislation. Therefore, we concluded that the washing water from the
purification step of biodiesel is an effluent that cannot be rejected before an appropriate treatment to be fit in the established standards. / Sendo o biodiesel um combustível derivado de energia renovável e considerado ecologicamente correto por ser de queima limpa, isto é, não libera para atmosfera gases que contribuem para o aumento do efeito estufa, este biocombustível surge como alternativa para substituir aqueles derivados do petróleo. As matérias-primas utilizadas para produzir o biodiesel podem ser tanto de origem vegetal como origem animal. Ante o impasse e o uso das matérias-primas vegetais serem também utilizadas para outros fins, como, por exemplo, a alimentação, as matérias-primas derivadas de gorduras de origem animal, como o óleo extraído das vísceras de peixe, aparece como interessante fonte de pesquisa para o aproveitamento na produção do biodiesel. No Ceará, o açude Castanhão possui um dos maiores criatórios de tilápia, uma espécie de peixe que resiste até em águas bastante poluídas e, por essa razão, se reproduzem com facilidade, servindo como alimento, principalmente nas cidades interioranas. Em paralelo a essa vantagem, também ocorre como desvantagem o descarte das vísceras do peixe, uma fração que não tem uso, em solos e águas superficiais, ocasionando sérios problemas ambientais. Com o intuito de minimizar o citado problema, a Associação dos Pisicultores do Açude Castanhão, em parceria com a Fundação Núcleo de Tecnologia Industrial do Ceará (NUTEC) iniciaram uma pesquisa de aproveitamento dessas vísceras para a produção de biodiesel. A pesquisa foi desenvolvida na NUTEC e a produção de biodiesel de vísceras de tilápia mostrou ter viabilidade. Durante a produção de biodiesel, no entanto, são gerados efluentes de elevadas cargas poluidoras, em razão dos reagentes usados e da própria composição da matéria-prima. Estes efluentes, chamados águas de lavagem, são provenientes da etapa de purificação do biodiesel, a lavagem aquosa. O biodiesel foi obtido por meio de uma reação química de transesterificação, isto é, a gordura (óleo extraído das vísceras de tilápia) foi convertida em um éster (biodiesel) na presença de um álcool (metanol) e um catalisador (hidróxido de sódio). Em seguida, as águas de lavagem provenientes dessa etapa foram caracterizadas mediante análises físico-químicas dos parâmetros: pH, amônia total, demanda química de oxigênio (DQO), fósforo total e teor de metanol, seguindo-se os procedimentos descritos em APHA (1998 e 2005) e (European Standard EN-14110/2001 - VARIAN). Comparando-se os resultados obtidos com os padrões estabelecidos para lançamento de efluentes da Resolução
CONAMA Nº 430, de 13 de maio de 2011, observou que as concentrações dos parâmetros analisados não estavam em conformidade com a citada legislação ambiental federal. Portanto, conclui-se que as águas de lavagem provenientes da etapa de purificação do biodiesel, são efluentes que não podem ser descartados antes de um tratamento adequado para enquadrá-las nos padrões estabelecidos.
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Prima facie status jako možné řešení hromadného přílivu uprchlíků / Prima Facie Status as a Possible Solution for Mass Influx of RefugeesRadová, Kateřina January 2018 (has links)
This thesis addresses the topic of mass influx of refugees and its possible solutions. It examines the concept of prima facie refugee status determination in group situations, which is plentifully used in states of the economic South as a solution to mass influx of refugees. Despite its ample use, it is not entirely clear what can be understood by it. A better way to tackle mass influxes of refugees is sought here in response to the European migration "crisis" which has shed light on the unpreparedness of the Common European Asylum System for a large scale influx. The prima facie refugee status determination is put here as an opposite to individualized refugee status determination, which is assumed by the western doctrine and practice to be the only possible way of determining refugee status under the 1951 Convention. Even though individualized refugee status determination may be an appropriate tool in times of relatively low number of refugees, as it has been the case for a long time at the European continent, it may be different in situations of mass influx of refugees. Such individualized refugee status determination is very costly and lengthy procedure and as such not very suitable for situation of mass influx of refugees. To answer the question of whether the prima facie refugee status...
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Vad kan man när man kan läsa noter? : hur erfar gymnasieelever fenomenet notläsning?Högquist, Marcus January 2014 (has links)
Utgångspunkten för den här uppsatsen var att undersöka vad som är kunnandet inom fenomenet notläsning. Den här uppsatsen ska ses som ett led i att undersöka detta och syftet med arbetet var att undersöka hur gymnasieelever erfar fenomenet notläsning, och då främst elever med en musikalisk bakgrund inom genrer som i första hand inte använder sig av noter vid instudering av musikaliskt material. Uppsatsen har därmed ett tydligt elevperspektiv och intresserar sig för elevernas olika uppfattningar. Uppsatsen använder sig av observationer och intervjuer som metod och resultaten av dessa ligger till grund för en fenomenografisk analys, vars utfall diskuteras relaterat till tidigare forskning inom området. Resultaten visar att eleverna uppfattar notläsning som ett fenomen vars kunnande består av flera olika kunskaper och förmågor. Detta leder vidare till resonemang om att identifiera de viktiga aspekterna av kunnandet och att erbjuda elever möjlighet att urskilja dessa aspekter i undervisningen samt att kunskaperna och förmågorna är beroende av varandra för ett musikaliskt resultat. Resultaten visar att eleverna uppfattar att kunnandet dels har likheter med andra kunnande, som språk och matematik, men också att det är ett unikt kunnande. Undersökningen visar också på noternas roll och funktion som kommunikationsmedel och arbetsmaterial för olika musikutövare.
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Aquinas on Motion:Porter, Nicholas January 2023 (has links)
Thesis advisor: Eileen Sweeney / Motion is the central phenomenon that Aristotle's physics endeavors to explain, and the whole superstructure of his natural philosophy is bound to it. This was certainly understood by Thomas Aquinas, who produced a most careful and thorough account of the Aristotelian theory of motion. What is rarely recognized is that in so doing he developed and improved that theory in a number of respects. This dissertation is a study of the theory of physical motion in Aquinas. It has two principal results. The first regards the concept of motion itself. Aquinas accepts Aristotle's definition of motion, but gives his own explanation of it, one which employs non-Aristotelian ideas like participation, and places motion in a more general and cohesive system of relations between non-being and being. The second regards what is called natural motion, i.e., that which inanimate matter exhibits of its own accord. How Aquinas explains this has rarely been understood and has frequently been misunderstood. I provide a thorough, systematic treatment that sets forth the principles underlying Aquinas's theory of natural motion, explains in what sense such motion is said to be caused, and notes – what commentators are prone to overlook – the critical role played by analogy as an aid to grasp the causality of natural motion. Chapter 1 briefly introduces Aquinas as a medieval "physicist", i.e., natural philosopher, specifies the scope of the dissertation, and lays out the path to be followed in the succeeding chapters. Chapter 2 summarizes what Aristotle says about motion in his Physics. His definition of motion is presented, and the terms in which it is given are analyzed. As the definition is famously perplexing, and its meaning a matter of debate, the opinions of a number of modern commentators are reviewed. After having explained the primacy that Aristotle assigns to locomotion and the connection he establishes between motion and time, the chapter concludes with a section on the causes of motion. This covers Aristotle's arguments for the eternity of motion, his denial of pure self-motion, introduces his views on animal, natural, and violent motion, and concludes with the first mover and first motion reached at the end of the Physics. Chapter 3 is a short introduction to the tradition of Aristotelian commentary. It contains brief reviews of some of what Simplicius, John Philoponus, Averroes, and Avicenna say about the Aristotelian theory of motion, with especial attention given to those aspects of it with which they disagree or which they find troublesome. The next three chapters are devoted to Aquinas. Chapter 4 covers how Aquinas interprets Aristotle's definition of motion and how he integrates it into his own metaphysics. The chapter begins with two preparatory notes. First, it introduces Aquinas as a commentator, and stresses the importance of having the context of the commentary tradition in mind when reading Aquinas, because he belongs to it and approached Aristotle in much the same way as earlier commentators. This has the consequence that his own developments are somewhat concealed, since what he says in his commentary on the Physics is presented as straightforward exposition, without any suggestion of originality. Second, modern readers are cautioned not to import modern senses of "motion" unwittingly into Aquinas, as this leads to confusion. The point is made that his Latin usage is regular and well-defined. After this, Aquinas's interpretation of the definition of motion is presented and what he means by calling it "imperfect act" is explained. This involves a sophisticated theory of the order of act to act, and incorporates the Neoplatonic language of participation and perfection. The next section of the chapter presents some of the analyses that Aquinas makes of motion, including its mental character and categorization. It is noteworthy, yet in fact quite unnoticed, that Aquinas provides a subtle and inventive solution to a modern debate over the proper interpretation of the definition of motion (the so-called "process" vs. "non-process" debate) which reconciles the two sides. Finally, I present a visual analogy as an aid for grasping how motion fits into a larger Thomistic metaphysical scheme concerning the relationship between non-being and being. Chapter 5 treats Aquinas's account of natural motion. It begins by noting some of the problems involved with Aristotle's explanation of natural motion, including, critically, that of the cause of such motion. It then highlights the work of James Weisheipl, who rejected a motor coniunctus interpretation of natural motion and offered in its stead his own, one which has since become well-known. But a careful examination of what Aquinas says shows that Weisheipl's interpretation of him is incorrect, and must also be rejected. The chapter then lays out (1) the principles of motion and their schematic organization; (2) Aquinas's theory of efficient causality and how we are to understand his denial of the possibility of action at a distance; (3) his use of analogies to indicate how we are to understand the efficient cause of natural motion; and then finally (4) shows, first, how the multiplicity and variation of the analogies lead commentators to misread Aquinas, and, then, how they illuminate other aspects of his theory of motion. Chapter 6 treats, in turn, the much debated principle that "everything that is moved is moved by another", and then the arguments that Aquinas gives for the existence of an unmoved mover, which he takes to be God. With regard to the first, it is pointed out that the theory of inertia is not nearly so fatal to the principle as many historians of science assume. Indeed, understood in light of what was said about Aquinas's understanding of the efficient causality involved in natural motion in the preceding chapter, it is compatible with inertia. However, a review of the three arguments Aquinas takes from Aristotle purporting to prove the principle are all found to be subject to serious objections. Greatest attention is given to the argument drawn from the claim that a thing cannot simultaneously be in act and in potency in the same respect. With regard to the second, it is shown that what Aquinas has to say about the unmoved mover is perplexed and inconsistent. Aquinas accepts two series of arguments from Aristotle, one from the Physics that concludes to a first moving cause, another from the Metaphysics that concludes to a final cause. From the former, Aquinas constructs his own argument from motion, most famously presented as the prima via, but at times he attempts to combine the two Aristotelian series. It is shown that these attempts at harmonization involve Aquinas in inconsistencies. What the prima via revision concludes to is also discussed. An important observation is that the prima via is manifestly intended by Aquinas to be an argument from physical motion. Yet numerous commentators, perceiving its weakness, attempt to recast it in a non-physical form, such that "motion" no longer signifies what Aquinas intends. The chapter ends with some cautious remarks on the state of these highly controversial topics. Chapter 7 concludes the dissertation, first, with a brief recapitulation of some of its major points, and then with some speculation as to what use its results may have for future scholarship. / Thesis (PhD) — Boston College, 2023. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Philosophy.
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L’oggetto in generale. L’orgoglio dell’ontologia da Clauberg a Leibniz / L’objet en général. L’orgueil de l’ontologie de Clauberg à Leibniz / The object in general. The pride of ontology from Clauberg to LeibnizRagni, Alice 30 September 2016 (has links)
Par le néologisme ontologia (1606), on indique à l’époque moderne la science générale, autre que la théologie, dont l’objet est l’ens quatenus ens est avec ses propriétés transcendantales. De cette tradition, qui voit le jour dans le cadre de la Schulmetaphysik, ce travail examine l’âge « post-claubergien », c’est à dire les années qui suivent la diffusion et la réception de l’Ontosophia (1647) de Johannes Clauberg et notamment la troisième et dernière édition de son écrit, la Metaphysica de ente (1664), qui témoigne de son adhésion au cartésianisme. Cette phase de la Schulmetaphysik est marquée par la question de l’organisation de la métaphysique sur la base de la « dissociation », non plus de la « partition », entre la doctrine générale de l’étant (ontologia ou ontosophia) et la science des substances immatérielles (pneumatica ou pneumatologia). Cette « canonisation » de l’ontologie est attestée dans les lexiques philosophiques, mais elle est confirmée aussi par les critiques qui sont adressées à l’« ontologisation » de la métaphysique et jusqu’au rejet leibnizien de l’ontologie. Les traités d’ontologie suivent la tendance à une restriction de leur objet selon son fundamentum in re (« ontologie réelle ») ou à une extension de cet objet au pure intelligibile (« ontologie noétique »). On examine en dernier lieu la question de l’identité de l’ontologie et de la prima philosophia et, de celle-ci, le caractère de science post-physique. En ce sens, Jean-Baptiste Du Hamel et Ehrenfried Walter von Tschirnhaus, figures étrangères au contexte réformé et protestant, s’engagent dans des tentatives originales de légitimation non seulement « horizontale » (formelle), mais aussi « verticale » (subjective) de l’ontologie. / In early modern philosophy the neologism ontologia (1606) comes to indicate the general science, other than theology, whose object is the ens quatenus ens est, along with its transcendental properties. The present work analyses the “Post-Claubergian” period of the ontology tradition, which originated in the Sculmetaphysik context. These were the years that followed the circulation and reception of Johannes Clauberg’s Ontosophia (1647) and what would become its third and last edition, Metaphysica de ente (1664), which included the new elements of Clauberg’s Cartesianism. This period of the Schulmetaphysik is connected mainly to the question of the organization of metaphysics, based on the “dissociation”, and no longer “partition”, between the general science of being (ontologia or ontosophia) and the science of immaterial substances (pneumatica or pneumatologia). The “canonization” of ontology is attested by philosophical lexicons, but also by the criticism directed to the “ontologization” of metaphysics, up to Leibniz’s refusal of ontology. Treatises of ontology tend to limit their object on the basis of its fundamentum in re (“real ontology”) or to extend it to the pure intelligibile (“noetic ontology”). Finally, this study considers the question of the identity of ontology with prima philosophia and the nature of this latter as a post-physical science. In this sense, Jean-Baptiste Du Hamel and Ehrenfried Walter von Tschirnhaus, both stranger to the Protestant and Riformed scolastic context, provide an original attempt to establish ontology not only “horizontally” (formally), but also “vertically” (subjectively).
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Diane Di Prima: The Muffled Voice of the Beat GenerationGoggans, Heather 08 1900 (has links)
The Beat rejection of conventional values meant a rejection of marriage, family, and a nine-to-five job, and few women were prepared to make that kind of radical shift in a society that condemned women for behaving the way the Beats behaved. Though she has faced difficulty in getting published, Beat writer Diane Di Prima has been publishing steadily for the past forty years. Di Prima has also lived the life of a Beat, wandering the country, avoiding nine-to-five work and supporting herself with grants, teaching and poetry readings. In spite of her success and adherence to the Beat lifestyle, Di Prima has given birth to five children, all of whom she took with her in her travels. Diane Di Prima has always faced the particular challenge of gaining the acceptance of her male peers amid indifference and hatred toward her sex while not allowing these men to go unanswered.
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Sekunda vista : Konsten att snabbinterpretera / Secunda vista : the art of fast musical interpretationWettergren, Sandra January 2022 (has links)
Syftet med denna studie är att utforska och utveckla min förmåga att sjunga utryckfullt när det ges kort instuderingstid. Ambitionen är att förbereda mig inför ett så kallat sekunda vista-prov där gestaltning av text och musik är i förgrunden. Hur ser processen ut när jag försöker utveckla min förmåga att väva samman text och musik vid ett ge- staltningsprov med kort förberedelsetid? Under sammanlagt 6 veckor övades olika färdigheter rörande sekunda vista, prima vista, gehör, textlig och kroppslig gestaltning. Övningen skedde dagligen med stöd från en egen utformad lista: Träna intervall utan ord, sjunga intervall utan ord men med olika uttryck, sjunga korta melodifraser utan ord med olika uttryck, läsa korta fraser och gestalta texten, sjunga korta fraser och gestalta texten musikaliskt samt med en mobil-app kallad Ella. I slutet av varje vecka spelades en kortare tysk romans in där 40 minuter gavs som förberedelsetid. Roman- sen skulle för mig vara sedan tidigare helt okänd. I sammanfattningen av studiens ge- nomförande kan det konstateras att jag främst lägger fokus på att sjunga rätt toner, att sjunga med god sångteknik och att jag försöker få med ett kroppsligt uttryck vilket då blir på viss bekostnad av det musikaliska uttrycket. / The purpose of this study is to explore and develop my ability to sing expressively when given a short rehearsal time. The ambition is to prepare myself for a so-called secunda vista-test where the performance of text and music is in the spotlight. What does the process look like when I try to develop my ability to weave together text and music with very short preparation time? For a total of 6 weeks, various skills were practiced concerning secunda vista, prima vista, aural training, textual and physical ex- pression. The practice took place daily with the support of a prepared list: Practice intervals without words, sing intervals without words but with different expressions, sing short melodic phrases without words with different expressions, read short phrases and shape the text, sing short phrases, and shape the text musically, and with a mobile app called Ella. At the end of each week a short German lied was recorded where 40 minutes were given as preparation time. The lied was to me completely un- known before. In the summary of the study, it can be identified that my focus is mainly on singing the right notes, singing with good singing technique, and trying to get a physical expression, which then becomes at some expense of the musical expression.
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Televizní zpravodajství o koronavirové epidemii 2020 jako možný svět / Broadcast coverage of the coronavirus epidemic 2020 as a possible worldBergerová, Michaela January 2021 (has links)
This diploma thesis explores the theory of possible worlds and its relation to broadcast during the coronavirus pandemic. It perceives news, especially broadcast, as a possible world. Using narrative analysis, this thesis describes the characteristics of two possible worlds that arose during the first wave of the coronavirus pandemic on Czech Television and television Prima. The main goal of this research is to examine what kind of possible worlds have these two TV stations constructed in their main news programs and to point out how these two possible worlds differed. My diploma thesis should primarily contribute to a clear comparison of how the depiction of the coronavirus pandemic differed by individual television channels in the first half of 2020.
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"Jag glömmer bort vad tonerna heter" : att läsa a prima vista på gitarrEk, Viktor January 2017 (has links)
Syftet med denna studie är att undersöka hur musikhögskolestudenter med inriktning gitarrpedagog läser a prima vista. För att undersöka detta gjordes ett experiment där jag skrev tre olika notexempel som tre blivande gitarrpedagoger ur årskurs 1 på en musikhögskola fick spela. Detta observerades genom videoobservationer för att kunna analyseras med utgångspunkt i variationsteorin i efterhand. Som bakgrund för studien har jag tagit fram forskning om bland annat gitarrens uppbyggnad, gehör, notläsningsstrategier och notläsning i jämförelse med läsinlärning. Resultatet visade bland annat att förmåga att utläsa tonhöjd och att välja fingersättning var det som informanterna hade mest problem med. I diskussionsdelen diskuteras resultatet i förhållande till bakgrunden men även ur ett didaktiskt perspektiv.
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Abordagem do problema de cutting stock na indústria florestalParra Gálvez, Juan Leandro Andrés January 2014 (has links)
Em diferentes países a indústria da floresta é considerada um setor estratégico que contribui fortemente na geração de matéria-prima, tributos, geração de empregos e produtos para exportação. Neste setor industrial, o segmento de madeira serrada destaca-se pelos volumes de atividade econômica que movimenta e sua ligação com outros setores econômicos como a construção civil ou a indústria de móveis. A partir da crise econômica dos anos 2008-2009, que atingiu fortemente o mercado de exportação, as empresas de serrado da madeira desses países estão envolvidas em ser mais eficientes no processo de corte da matéria-prima. Estas empresas enfrentam o problema de cortar peças de madeira retangulares regulares, de clientes do mercado interno ou externo, a partir de estoque de toras. A complexidade deste problema que precisa atenção é que o corte na matéria-prima é sobre uma superfície de característica circular utilizando o padrão de corte" Cant Sawing". Este padrão especifica as peças laterais e centrais para o corte desde a superficie de uma tora de madeira. A presente tese apresenta uma formulação matemática para o problema. Dois diferentes métodos de solução foram desenvolvidos para resolução do problema. O primeiro está baseado no método de programação linear inteira, e o segundo em um método de aproximação, que usa a metaheurística "Simulated Annealing". Estes métodos de solução são executados por etapas. Primeiro os padrões de corte são determinados considerando o estoque de matéria-prima e as demandas dos clientes. Na segunda etapa, o processo de otimização é executado para estabelecer os padrões de corte adequados para cada tipo de matéria-prima, os quais deveriam ser utilizados na linha de produção, com o objetivo de diminuir as perdas de madeira no processo de serrado dos produtos retangulares a partir das toras. Os resultados conseguidos mediante os métodos foram comparados com dados reais, com o objetivo de incrementar a eficiência visando diminuir os custos operativos do processo. Dados reais de uma serraria do Rio Grande do Sul foram utilizados para validar o modelo, e em valor diminuiu as perdas em 6, 2%, em comparação com o método manual utilizado pela empresa. / In severa! countries the forest industry is considered as a strategic economic sector, which strongly contributes for raw material production, collection of taxes, and for increases on job generation and on the manufacture of products for export. In this industry sector, the sawn timber segment stood out due to its volumes of economic activity as well as dueto its relationships with certain sectors, as construction or furniture industries. Since the 2008-2009 global financiai crisis, which has strongly struck the export markets, the sawmills have been involved into a search of higher leveis of efficiency on the process of sawing the raw material. These companies face the problem of regular sawing rectangular pieces of wood, from their stocks of wood logs for different clients of their respective domestic and export markets. The complexity of this problem, is based on the fact that the cutting process on the raw material is made from a circular surface, using the "Cant Sawing" pattern. This pattern defines the lateral and central pieces for cutting from the surface of wood log.The present thesis describes a mathematical formulation for such a problem. Two different solution methods were developed to solve this problem. The first one is based an integer programming based-method, and the second one is an approximation method, which uses the simulated annealing metaheuristic. This solution method is run in stages. First, the sawing patterns are to be determined, considering the available stock of raw material as well as the customer demands. On the second stage, the optimization process is developed in order to achieve the most adequate sawing patterns to each kind of raw material, which are to be used in the production line, with the goal of reducing the losses of wood along the process of sawing the final products. The attained results by using the developed methods were tested with real data, and present values, aiming at increasing the efficiency on reducing the process operational costs process. Real data for a sawmill in Rio Grande do Sul, Brasil were used to validate model, and in value, reduces 6, 2% the losses when compareci with the manual method used by the company.
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