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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Potatisfibers inverkan på bröd : hur påverkas deg och bröd av potatisfiberns malningsgrad? / The impact of using potato fiber in bread : how does the potato fiber grind affect dough and bread?

Rothman, Emma, Erlandsson, Jakob January 2019 (has links)
Introduktion: Potatisfibern utgör ca 1 % av potatisens vikt och är en restprodukt vid tillverkningen av potatisstärkelse. Idag tillsätter flera välkända livsmedelsföretag potatisfiber i sina produkter. Den främsta anledningen till detta är för att fibern kan binda vätska 7–12 gånger sin egen vikt vilket kan ge en ekonomisk fördel. Syfte: Syftet med studien är att jämföra hur grovmalen respektive finmalen potatisfiber påverkar utvalda egenskaper i degen och brödet med särskilt fokus på brödets lagringsstabilitet. Metod: Pilottester Observationer av degegenskaper Mätning av vätskeförlust och brödvolym Instrumentell färgmätning med en kolorimeter Sensorisk bedömning av lagringsstabilitet   Resultat: Pilottester av båda malningsgraderna av potatisfibern visade att vid en jämförelse av olika förbehandlingar så som skållning, blötläggning och tillsats direkt i degen, gav direkt tillsats av potatisfiber i degen flest fördelar, främst gällande mjukheten i degen. Vid observationen fanns en synlig färgskillnad mellan bröden med tillsatts potatisfiber och referensbrödet men detta säkerställdes inte vid den instrumentella färgmätningen. Brödens volym och vattenhållande förmåga påverkades inte av tillsats av potatisfiber. Den sensoriska bedömningen visade en upplevd torrhetskänsla för bröd med tillsatt potatisfiber (båda malningsgraderna) när det testades mot ett referensbröd. Den finmalda fibern påverkade lagringsstabiliteten mer än den grovmalda fibern gjorde.   Slutsats: Malningsgraden gav inga märkbara skillnader på de utvalda deg- och brödegenskaperna. Potatisfiber hade inte tillräckligt stor påverkan på deg eller bröd för att antas vara lönsam att tillsätta vid brödbakning. / Introduction: The potato fiber constitutes about 1 % of the weight of the potato and is a residual product in the manufacture of potato starch. Today, several well-known companies add potato fiber to their products. The main reason for this is because the fiber can bind liquid 7–12 times its own weight, which gives an economic advantage. Aim: The aim of this study is to investigate how the grind of potato fiber affects selected characteristics in dough and bread, with particularly focus on the storage stability of the bread. Method: Pilot tests Observations of dough characteristics Measure of water exchange and bread volume Instrumental color measurement with a colorimeter Sensory evaluation of storage stability   Results: Pilot tests with both grinds of potato fiber showed that when comparing pre-treatments such as scalding, soaking and direct addition into the dough, a direct addition resulted with the most advantages, mainly regarding the softness of the dough. During the observations there was a visible difference in color between the potato fiber loaves and the reference loaf, which was not ensured in the instrumental color measurement. The volume and water retention in the bread was not affected by an addition of potato fiber. The sensory evaluation showed a perceived dryness for bread with added potato fiber (both grinds), when tested against a reference bread. The finely ground fiber affected the storage stability more than the coarse grounded fiber did. Conclusion: The grind gave no notable differences on the selected properties of dough and bread. The impact that grind had on dough characteristics and the finished bread were small.
92

Efeito da adição de amido resistente de milho e enzimas sobre as propriedades da massa de pão e as propriedades físicas do pão de forma. / Effect of the addition of resistant starch and enzymes on the rheological properties of bread dough and physical properties of pan bread.

Altuna, Luz 29 September 2015 (has links)
O amido resistente de milho (ARM) não é digerido em humanos fornecendo benefícios para a saúde tais como redução do colesterol, do índice glicêmico e fermentação no cólon. Porém, a substituição parcial de farinha de trigo (FT) por ARM em massa de pão resulta na diluição do glúten prejudicando a qualidade do produto. Massa de pão foi produzida com 12,5 g/100g de ARM e os efeitos das enzimas glicose-oxidase (Gox), tranglutaminase (TG) e xilanase (HE) na massa foram estudados. Massa produzida sem ARM e sem enzimas foi considerada padrão e massa produzida com ARM e sem enzimas foi considerada controle para comparação. Uma metodologia foi desenvolvida para medir o torque durante o amassamento em grande escala, utilizando um reômetro dinâmico adaptado. As propriedades reológicas foram avaliadas nos testes de medidas descritivas de textura, adesividade Chen-Hoseney, extensão uniaxial Kieffer, extensão biaxial e testes oscilatórios em reômetro. Pão produzido de acordo com as formulações padrão, controle e ótima foi avaliado com relação ao volume específico (VEP), firmeza do miolo, cor e análise sensorial para o atributo preferência. As três enzimas testadas influenciaram positivamente o torque máximo atingido durante o amassamento que variou entre (8,36 e 9,38) N m. Gox e TG apresentaram efeito positivo na altura máxima desenvolvida pela massa medida em reofermentógrafo enquanto que o efeito da HE foi negativo. Uma formulação com ARM e enzimas apresentou desempenho de panificação similar a massa padrão (altura máxima ajustada igual a (45,5 ± 3,9) mm), correspondente a adição de (4, 2,5 e 0,5) mg/100g de TG, Gox e HE respectivamente (ótima). A formulação ótima apresentou adesividade, trabalho de adesão, coesividade, dureza, resiliência, resistência à extensão e extensibilidade similares a massa padrão e diferentes da massa controle. As enzimas aumentaram o índice de strain hardening reduzido pela adição de ARM. Para o pão de forma, o VEP variou entre (3,16 e 3,64) cm3/g (diferença não significativa) e o pão produzido com a formulação ótima foi o mais escolhido como preferido. Durante o armazenamento por até 7 dias, o ARM diminuiu a taxa de envelhecimento do pão enquanto que as enzimas apresentaram efeito oposto. Em geral, a substituição parcial de FT por ARM reduziu a elasticidade da massa diminuindo a qualidade do pão enquanto que as enzimas minimizaram esse efeito. / Resistant starch (RS) is not digested by humans providing benefits for health such as reduction of blood LDL cholesterol levels, reduction of post-prandial blood glucose and fermentation in the colon. However, partial replacement of wheat flour (WF) with RS prejudices bread quality due to gluten dilution. Dough was formulated with 12.5 g/100g of RS and the effects of the enzymes glucose-oxidase (Gox), tranglutaminase (TG) and xylanase (HE) were studied. Dough produced without RS or enzymes was considered as regular and dough produced with RS and without enzymes was considered as control for comparison. A methodology was developed to measure torque during dough mixing in large scale using a dynamic rheometer. With respect to dough rheology, tests performed included texture profile analysis, Chen-Hoseney stickiness, Kieffer uniaxial extension, biaxial extension and oscillatory tests in rheometer. Bread was produced from regular, control and optimum formulations and the quality was assessed concerning specific volume, firmness, color and preference by sensory panel. The three enzymes tested influenced positively the maximum torque during mixing which varied between (8.36 and 9.38) N m. Gox and TG showed positive effects on the maximum height developed by dough measured in rheofermentometer while HE showed a negative one. A formulation with RS and baking performance similar to regular dough was found (adjusted maximum height equal to (45.5 ± 3.9) mm), corresponding to (4, 2.5 and 0.5) mg/100g of TG, Gox and HE respectively (optimum). The optimum formulation showed stickiness, work of adhesion, cohesiveness, hardness, resilience, resistance to extension and extensibility, similar to the regular dough and statistically different from control dough. Strain hardening index was reduced by the addition of RS and increased by the addition of enzymes. Regarding bread tests, specific volume of bread varied between (3.16 e 3.64) cm3/g (not significant difference) and the bread produced with theoptimum dough was the most preferred by the sensory panel. During 7 days of storage, RS reduced the aging rate while enzymes had the opposite effect. In general, WF replacement by RS reduced dough elasticity affecting the bread quality while enzymes helped minimizing this effect.
93

Étude de la confiance dans les transactions « m-banking » : cas de « Orange money » au Mali / Study of trust in mobile banking : case of Orange money in Mali

Sagara, Cheick Oumar 06 October 2015 (has links)
L’étude de la confiance dans le domaine des sciences de l’information et de la communication revêt une importance capitale pour cette discipline au carrefour des autres. Elle permet d’affiner mais aussi de compléter les connaissances pour une meilleure appréhension des phénomènes informationnels et communicationnels. La confiance du fait de sa nature jugée trop théorique, reste très peu mobilisée dans les recherches comme une variable explicative des phénomènes de l’information et de la communication.L’objectif de ce travail est de mesurer le niveau de confiance des utilisateurs dans « orange money ». Ce service de transaction monétaire par téléphone mobile fait désormais partie de la gamme des services proposés à la population malienne par la société de télécommunication Orange Mali. En vue d’atteindre cet objectif, un questionnaire a été administré auprès de 309 citadins dans le district de Bamako (Mali).Les résultats issus du traitement et de l’analyse des données collectées montrent que, les répondants ont un niveau élevé de confiance dans les transactions monétaires sur téléphone mobile. Cependant, il ressort de ces résultats une méfiance généralisée des participants à l’enquête à donner leurs informations personnelles à Orange Mali. L’ensemble de ces résultats sont interprétés dans un chapitre dédié.Le présent de thèse s’articule autour de dix chapitres. Il se compose de trois grandes parties dont la première est consacrée à la présentation des concepts théoriques de la confiance, le contexte économique et social. La deuxième partie se focalise sur l’analyse des données et l’interprétation des résultats de l’étude. La troisième partie est focalisée à la mise en perspectives des principaux résultats de ce travail. / The study of trust in the field of information and communication science is of paramount importance in this discipline at the crossroad of others research field. It helps to refine and to supplement the knowledge to a better understanding of informational and communicational phenomena. Trust due to it theoretical aspects, is rarely mobilized in research as an explanatory variable in information and communication sciences.The objective of this work is to measure the level of trust of "Orange Money" users. This money transfer system based on mobile phone is now part of the range of services offered by the company of telecommunications Orange Mali to Malian populations. In order to achieve this, a questionnaire was administered to 309 citizens in the district of Bamako, the main city of Mali.Results from the processing of collected data show a high level of confidence of users in monetary transactions by mobile phone. However, the result shows a general distrust of survey participants to give their personal information to Orange Mali. All these results are interpreted in a dedicated chapter.The present thesis focuses on ten chapters organized into three parts: the first is devoted to the presentation of theoretical concepts on trust, economic and social context. The second part focuses on the analysis, processing and interpretation of data collected on our field survey. And finally, in the third part, we try to put into perspective the results.
94

Recuperação de metais a partir da lama vermelha / Reclamation of metals from red mud

Aguirre, Marcos 25 August 2015 (has links)
Submitted by Bruna Rodrigues (bruna92rodrigues@yahoo.com.br) on 2016-09-15T19:43:41Z No. of bitstreams: 1 TeseMA.pdf: 4330905 bytes, checksum: 6cb5f6465c74b22135d461ab86d86511 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-16T19:55:34Z (GMT) No. of bitstreams: 1 TeseMA.pdf: 4330905 bytes, checksum: 6cb5f6465c74b22135d461ab86d86511 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-16T19:55:39Z (GMT) No. of bitstreams: 1 TeseMA.pdf: 4330905 bytes, checksum: 6cb5f6465c74b22135d461ab86d86511 (MD5) / Made available in DSpace on 2016-09-16T19:55:47Z (GMT). No. of bitstreams: 1 TeseMA.pdf: 4330905 bytes, checksum: 6cb5f6465c74b22135d461ab86d86511 (MD5) Previous issue date: 2015-08-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / This paper describes an integrated process for recovering aluminum, iron, titanium, sodium and silica from red mud through a hydrometallurgical treatment sequence. The disposal of red mud, which is the largest waste produced by the aluminum industry, causes considerable environmental problems, and impacts costs greatly. This work presents a proposal to deal with it. Firstly, red mud is subjected to calcination at the 500-600°C range (thermal activation) so as to modify the structure of the metals present in red mud and make the attack with sulfuric acid easier. Next, the red mud is mixed with sulfuric acid and calcinated at 250- 300 °C (acid calcination). After digestion, the metal sulfates in the cake are dissolved by leaching with water and separated from the silica by filtration . Two routes to recuperate the leached metals are presented here, and the second one is analyzed economically. In this second method, silica is separated by filtration and all other metals in the leached solution are precipitated through a hydrometallurgical process in the form of their oxides. The remaining products present high purity level, thus being more easily marketed. / Este documento descreve um processo integrado para a recuperação de alumínio, ferro, titânio,sódio e sílica numa sequência de tratamento hidrometalúrgico da lama vermelha. A eliminação de lama vermelha, que é a maior resíduos produzidos pela indústria de alumínio, provoca consideráveis problemas ambientais e impactos custa muito. Este trabalho apresenta uma proposta para lidar com eles. Em primeiro lugar, a lama vermelha é submetida a calcinação no intervalo de 500-600 ° C(ativação térmica), para modificar a estrutura de metais presentes na lama vermelha, o que facilita o ataque com ácido sulfúrico. Em seguida, a lama vermelha e misturada ,com ácido sulfúrico, e levada à calcinação com ácido sulfúrico, a 250- 300 ° C (calcinação ácida). Após a digestão, os sulfatos de metal no bolo são dissolvidos por lixiviação com água, e separados da silica por filtração. São apresentados dois métodos para recuperação dos metais que foram lixiviados,sendo que a segunda alternativa, apresentada é avaliada ecônomicamente. A sílica é separada por filtração , e todos metais da solução lixiviada , são separados por processos hidrometalurgicos, na forma dos seus respectivos óxidos, apresentam grande pureza ,sendo facilmente comercializáveis
95

Constru??o e an?lise de desempenho de um forno/fog?o solar tipo caixa constru?do a partir de uma sucata de pneu

Gomes, Jailton Weber 24 April 2009 (has links)
Made available in DSpace on 2014-12-17T14:57:55Z (GMT). No. of bitstreams: 1 jailtonWG.pdf: 3426096 bytes, checksum: a6ff181ad34e9b5be394de7ebee923b3 (MD5) Previous issue date: 2009-04-24 / An alternative box-type solar cooker built starting from the scrap of a tire and a scrap of old office chair is presented, which principles functions are the effect greenhouse and the concentration. The tire served as structure for making of is the baking enclosure where the absorber (roasting pan 20x30cm) of the solar is located, being re-covered for a glass blade for the generation of the greenhouse effect isolated lateral and having deep its and for a composite the plaster base and EPS. Segments of plain mirrors had been placed in the laterals of the oven/cook for the concentration of the radiation and a reflecting parable was introduced in the baking enclosure for the exploitation of the incident reflected radiation inside of the oven/cook. The oven/cook is mobile to allow one better aiming of exactly in relation to the apparent movement of the sun. The thermal economic and of materials viabilities of the stove/cook in study will be demonstrate. The average internal temperature of the absorber was around 152,3?C and the internal temperature around 110?C. Will demonstrate that toits low cost and good thermal performance, represents basic characteristics for the viability of large use of such archetype, mainly for cooking the decreases and averages temperatures. One will reveal that the archetype in study is competitive with the box-type solar cooker conceived in the whole world / Apresenta-se um forno/fog?o solar alternativo de baixo custo para ser utilizado nas opera??es de assar e cozinhar, que foi constru?do a partir de uma sucata de pneu. O pneu foi cortado na parte superior para aumentar a ?rea de capta??o da radia??o solar incidente. Utilizou- se comp?sito a base de gesso, EPS (poliestireno expandido) triturado e ?gua para revestir internamente a carca?a do pneu e o fundo da mesma para minimizar as perdas t?rmicas. Ser?o estudadas tr?s configura??es, onde ser?o utilizados dois tipos de par?bolas refletoras. Uma confeccionada a partir de uma tampa de prote??o de uma sucata de ventilador e outra a partir de uma urupema, peneira usada para comidas de milho. Acima da cobertura de vidro foi colocada uma estrutura com espelhos planos para refletir os raios incidentes para o interior do forno/fog?o solar. A estrutura de sustenta??o do forno/fog?o solar, com os movimentos necess?rios ao acompanhamento do movimento aparente do sol foi confeccionada utilizando uma sucata de cadeira girat?ria. O forno/fog?o solar proposto apresenta maior viabilidade para a opera??o de assar. Obteve-se uma temperatura m?xima no absorvedor em torno de 160? e interna em torno de 120?C. Demonstrar-se-? as viabilidades t?rmica, econ?mica e de materiais do forno/fog?o solar proposto
96

Efeito da adição de amido resistente de milho e enzimas sobre as propriedades da massa de pão e as propriedades físicas do pão de forma. / Effect of the addition of resistant starch and enzymes on the rheological properties of bread dough and physical properties of pan bread.

Luz Altuna 29 September 2015 (has links)
O amido resistente de milho (ARM) não é digerido em humanos fornecendo benefícios para a saúde tais como redução do colesterol, do índice glicêmico e fermentação no cólon. Porém, a substituição parcial de farinha de trigo (FT) por ARM em massa de pão resulta na diluição do glúten prejudicando a qualidade do produto. Massa de pão foi produzida com 12,5 g/100g de ARM e os efeitos das enzimas glicose-oxidase (Gox), tranglutaminase (TG) e xilanase (HE) na massa foram estudados. Massa produzida sem ARM e sem enzimas foi considerada padrão e massa produzida com ARM e sem enzimas foi considerada controle para comparação. Uma metodologia foi desenvolvida para medir o torque durante o amassamento em grande escala, utilizando um reômetro dinâmico adaptado. As propriedades reológicas foram avaliadas nos testes de medidas descritivas de textura, adesividade Chen-Hoseney, extensão uniaxial Kieffer, extensão biaxial e testes oscilatórios em reômetro. Pão produzido de acordo com as formulações padrão, controle e ótima foi avaliado com relação ao volume específico (VEP), firmeza do miolo, cor e análise sensorial para o atributo preferência. As três enzimas testadas influenciaram positivamente o torque máximo atingido durante o amassamento que variou entre (8,36 e 9,38) N m. Gox e TG apresentaram efeito positivo na altura máxima desenvolvida pela massa medida em reofermentógrafo enquanto que o efeito da HE foi negativo. Uma formulação com ARM e enzimas apresentou desempenho de panificação similar a massa padrão (altura máxima ajustada igual a (45,5 ± 3,9) mm), correspondente a adição de (4, 2,5 e 0,5) mg/100g de TG, Gox e HE respectivamente (ótima). A formulação ótima apresentou adesividade, trabalho de adesão, coesividade, dureza, resiliência, resistência à extensão e extensibilidade similares a massa padrão e diferentes da massa controle. As enzimas aumentaram o índice de strain hardening reduzido pela adição de ARM. Para o pão de forma, o VEP variou entre (3,16 e 3,64) cm3/g (diferença não significativa) e o pão produzido com a formulação ótima foi o mais escolhido como preferido. Durante o armazenamento por até 7 dias, o ARM diminuiu a taxa de envelhecimento do pão enquanto que as enzimas apresentaram efeito oposto. Em geral, a substituição parcial de FT por ARM reduziu a elasticidade da massa diminuindo a qualidade do pão enquanto que as enzimas minimizaram esse efeito. / Resistant starch (RS) is not digested by humans providing benefits for health such as reduction of blood LDL cholesterol levels, reduction of post-prandial blood glucose and fermentation in the colon. However, partial replacement of wheat flour (WF) with RS prejudices bread quality due to gluten dilution. Dough was formulated with 12.5 g/100g of RS and the effects of the enzymes glucose-oxidase (Gox), tranglutaminase (TG) and xylanase (HE) were studied. Dough produced without RS or enzymes was considered as regular and dough produced with RS and without enzymes was considered as control for comparison. A methodology was developed to measure torque during dough mixing in large scale using a dynamic rheometer. With respect to dough rheology, tests performed included texture profile analysis, Chen-Hoseney stickiness, Kieffer uniaxial extension, biaxial extension and oscillatory tests in rheometer. Bread was produced from regular, control and optimum formulations and the quality was assessed concerning specific volume, firmness, color and preference by sensory panel. The three enzymes tested influenced positively the maximum torque during mixing which varied between (8.36 and 9.38) N m. Gox and TG showed positive effects on the maximum height developed by dough measured in rheofermentometer while HE showed a negative one. A formulation with RS and baking performance similar to regular dough was found (adjusted maximum height equal to (45.5 ± 3.9) mm), corresponding to (4, 2.5 and 0.5) mg/100g of TG, Gox and HE respectively (optimum). The optimum formulation showed stickiness, work of adhesion, cohesiveness, hardness, resilience, resistance to extension and extensibility, similar to the regular dough and statistically different from control dough. Strain hardening index was reduced by the addition of RS and increased by the addition of enzymes. Regarding bread tests, specific volume of bread varied between (3.16 e 3.64) cm3/g (not significant difference) and the bread produced with theoptimum dough was the most preferred by the sensory panel. During 7 days of storage, RS reduced the aging rate while enzymes had the opposite effect. In general, WF replacement by RS reduced dough elasticity affecting the bread quality while enzymes helped minimizing this effect.
97

Multiplatform Game Development Using the Unity Engine / Multiplatform Game Development Using the Unity Engine

Jašek, Roman January 2014 (has links)
Tato práce se zabývá možnostmi herního vývoje pro víceré platformy pomocí enginu Unity 3D. Rozebírá různé aspekty multiplatformního vývoje na počítačích i mobilních zařízeních. Důraz je kladen na analýzu tvorby her současně pro více platforem a problémy spojené s tímhle přístupem. Práce poskytuje možnosti řešení problémů, které vyvstanou při použití tohohle postupu, pomocí nástrojů, které poskytuje Unity 3D. Analýza se zabývá zejména na zvyšování výkonu her za použití metod dostupných na všech platformách vybraných pro testování. Tyhle vylepšení zahrnují způsoby jak snížit práci ve scéně a naopak zvýšit počet vykreslení za sekundu při zachování stejné vizuální kvality. Práce také nabízí pohled do minulosti tohoto odvětví a předpoklady o jeho příštím směrování.
98

An Online Input Estimation Algorithm For A Coupled Inverse Heat Conduction-Microstructure Problem

Ali, Salam K. 09 1900 (has links)
<p> This study focuses on developing a new online recursive numerical algorithm for a coupled nonlinear inverse heat conduction-microstructure problem. This algorithm is essential in identifying, designing and controlling many industrial applications such as the quenching process for heat treating of materials, chemical vapor deposition and industrial baking. In order to develop the above algorithm, a systematic four stage research plan has been conducted. </P> <p> The first and second stages were devoted to thoroughly reviewing the existing inverse heat conduction techniques. Unlike most inverse heat conduction solution methods that are batch form techniques, the online input estimation algorithm can be used for controlling the process in real time. Therefore, in the first stage, the effect of different parameters of the online input estimation algorithm on the estimate bias has been investigated. These parameters are the stabilizing parameter, the measurement errors standard deviation, the temporal step size, the spatial step size, the location of the thermocouple as well as the initial assumption of the state error covariance and error covariance of the input estimate. Furthermore, three different discretization schemes; namely: explicit, implicit and Crank-Nicholson have been employed in the input estimation algorithm to evaluate their effect on the algorithm performance. </p> <p> The effect of changing the stabilizing parameter has been investigated using three different forms of boundary conditions covering most practical boundary heat flux conditions. These cases are: square, triangular and mixed function heat fluxes. The most important finding of this investigation is that a robust range of the stabilizing parameter has been found which achieves the desired trade-off between the filter tracking ability and its sensitivity to measurement errors. For the three considered cases, it has been found that there is a common optimal value of the stabilizing parameter at which the estimate bias is minimal. This finding is important for practical applications since this parameter is usually unknown. Therefore, this study provides a needed guidance for assuming this parameter. </p> <p> In stage three of this study, a new, more efficient direct numerical algorithm has been developed to predict the thermal and microstructure fields during quenching of steel rods. The present algorithm solves the full nonlinear heat conduction equation using a central finite-difference scheme coupled with a fourth-order Runge-Kutta nonlinear solver. Numerical results obtained using the present algorithm have been validated using experimental data and numerical results available in the literature. In addition to its accurate predictions, the present algorithm does not require iterations; hence, it is computationally more efficient than previous numerical algorithms. </p> <p> The work performed in stage four of this research focused on developing and applying an inverse algorithm to estimate the surface temperatures and surface heat flux of a steel cylinder during the quenching process. The conventional online input estimation algorithm has been modified and used for the first time to handle this coupled nonlinear problem. The nonlinearity of the problem has been treated explicitly which resulted in a non-iterative algorithm suitable for real-time control of the quenching process. The obtained results have been validated using experimental data and numerical results obtained by solving the direct problem using the direct solver developed in stage three of this work. These results showed that the algorithm is efficiently reconstructing the shape of the convective surface heat flux. </p> / Thesis / Doctor of Philosophy (PhD)
99

Construction and Evaluation of a Numerical Model for Heat Transfer in a Ladle During Pre-heating : A Finite Volume Approach to the Diffusion Equation using Julia

Bjurstam, Gustaf January 2023 (has links)
Heat transfer is key to understanding many processes in engineering. At a steel mill heat transfer is absolutely crucial to understanding most of the processes. One such a process is the pre-heating of a freshly relined ladle. The goal of this project was to develop code which could solve the diffusion equation, in an arbitrary three-dimensional geometry, subject to Dirichlet, Robin, Neumann, and certain kinds of non-linear boundary conditions. In order to approximate the solution the code uses a cell centred finite volume methodology. In order to verify the computational correctness of the code it was used on three simple cases where analytic solutions are known, a rarity for three-dimensional boundary value problems. A mathematical model for the heat conduction inside a ladle at Ovako’s site in Hofors was developed. The model was evaluated based on measurements on the outside of the ladle as well as from a temperature probe inside the bottom of the ladle. The model was found to adequately agree with the measured temperature. The code can thus be used to find a more optimal heating regiment of the ladle, possibly reducing emissions. / Värmeöverföring är nyckeln till att förstå många processer inom teknik. På ett stålverk är värmeöverföring helt avgörande för att förstå de flesta av processerna. En sådan process är förvärmning av en nymurad skänk. Målet med detta projekt var att utveckla en kod som kunde lösa diffusionsekvationen i en godtycklig tredimensionell geometri under Dirichlet-, Robin-, Neumann- och vissa typer av icke-linjära randvillkor. För att approximera lösningen använder koden en cellcentrerad finita volymmetodik. För att verifiera kodens beräkningsmässiga korrekthet användes den i tre enkla fall där analytiska lösningar är kända, vilket är en sällsynthet för tredimensionella randvärdesproblem. En matematisk modell för värmeledningen i en skänk vid Ovakos anläggning i Hofors utvecklades. Modellen utvärderades utifrån mätningar på utsidan av skänken samt från ett termoelement inuti botten av skänken. Modellen visade sig stämma väl överens med den uppmätta temperaturen. Koden kan därför användas för att hitta ett mer optimalt uppvärmningsschema för skänken, vilket eventuellt kan minska utsläppen från processen.
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烘培業廠務管理資訊系統之建立以個案公司為例 / The process of building producing Management Information System of Baking - by case company

王友讓, Wang, Yue-Lang Unknown Date (has links)
生產管理是烘焙業經營的核心功能,生產主管於日常運作中管理之主要項目為1. 技術資訊管理2. 物料需求及存貨管理3. 進度控制管理4. 成本管理5. 製程安排管理。以西點麵包單店之管理角度言之,1. 配方表2. 製作技術3. 製程安排4. 生產成本5. 原物料管理為其最關心事。   個人電腦在台灣已經被普遍運用,以電腦處理資訊是必然趨勢,烘焙業中之連鎖店,因其規模經濟可引進電腦化,一般街坊為數甚多之西點麵包店,則仍沿襲「老闆-伙計」之管理方式,又因投資效益及經營者能力問題,雖知電腦之運用可幫助管理之進步,但是連標準化作業之建立皆屬不易,更不論電腦化之提昇。   本文主要之目的,即以經營西點麵包店之實務管理經驗,運用目前普遍使用之EXCEL軟體,於個人電腦建立廠務管理資訊系統,以提供西點麵包店業者1. 標準建立2. 管理輔助之管理工具。   本研究結果顯示;麵包店可經由標準化、電腦化的管理過程,提昇經營的效益,除了利潤成果外更可因顧客滿意而建立永續經營的基礎。

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