Ces travaux de thèse portent sur la caractérisation des milieux poreux fortement déformables afin de modéliser le transfert réalisé au cours du séchage. La théorie de consolidation de Biot traduit le couplage hydromécanique se produisant durant la déshydratation d’un milieu poreux déformable. Le modèle de Cáceres s’appuie sur cette théorie et sur la loi classique de Darcy. Il est adapté aux grandes déformations du squelette solide et utilise un tenseur de contraintes de décomposition Terzaghi. Une simulation de la déshydratation par l’intermédiaire de ce modèle nécessite au préalable le renseignement de celui-ci en termes de caractéristiques thermophysiques. Deux dispositifs expérimentaux ont été mis en place : l’un mesurant la relaxation de charge, l’autre réalisant la pressurisation dynamique (DP). La 1ère expérience nous a permis de caractériser la perméabilité, le coefficient de Poisson et le module d’Young en fonction de la teneur en eau du gel. La 2ème expérience a révélé l’importance de la prise en considération de la compressibilité de la phase solide dans la modélisation du séchage du gel d’agar ainsi que, la nécessité de corriger la valeur du module de compressibilité de l’eau contenant du gaz dissout. Suite à cette étape expérimentale, nous avons concentré nos efforts sur la modélisation liée à notre étude. Tout d’abord, la DP étant conforme à l’hypothèse de faibles déformations, un modèle numérique basé sur les équations de Biot a été réalisé afin de valider les paramètres mesurés et de corriger la valeur estimée de la perméabilité. Un second modèle traduit le couplage thermo-hydro-mécanique lors du séchage convectif d’un milieu poreux fortement déformable comme les gels d’agar et d’alumine. Ce dernier s’appuie sur la théorie de Biot et d’une part s’adapte aux fortes déformations et d’autre part utilise l’approche eulérienne. Ce modèle constitue donc un compromis entre les modèles de Biot et de Cáceres et s’appuie sur l’étude thermodynamique de Coussy ce qui est une avancée dans la modélisation des gels déformables. / This thesis focuses on the characterization of strongly deformable porous media in order to model the transfer taking place during drying. The theory of consolidation of Biot reflects the hydro-mechanical coupling occurring during dehydration of a deformable porous medium. Cáceres developed a model based on this theory and on the classical Darcy’s law. It is suitable for large deformations of the solid skeleton and the stress tensor is decomposed according to the so-called Terzaghi’s principle. A simulation using this model requires the information in thermo-physical terms of characteristics. Two experimental setups were developed : one measuring the relaxation charge, the other called dynamic pressurization (DP). The first experiment allowed us to characterize the permeability, Poisson’s ratio and Young’s modulus as functions of water content of the gel. The second experiment showed the importance of taking into account the compressibility of the solid phase in the modeling of the drying of agar gel as well as the effect of the existence of bubbles on the bulk modulus of the water. The establishment of two models followed this experimental study. First, the DP is consistent with the hypothesis of small deformations, a numerical model based on Biot’s equations was carried out to validate the parameters measured and to correct the estimated value of the permeability. A second model reflects the thermo-hydro-mechanical coupling in the convective drying of highly deformable porous media such as agar gel and alumina. The latter is based on the Biot’s theory and on the thermodynamics study of Coussy. It uses the Euler’s method while staying adapted to large deformations.

Margretelund wastewater treatment plant (WWTP) operated by the water utility Roslagsvatten AB, wasbuilt in 1956 and is located in Åkersberga town, Stockholm County, Sweden. Margretelund WWTP waslast renovated in 1999, and has been operated with the same physical, chemical, and biological processessince then. Due to issues with increased phosphorus emissions connected to increased concentration ofeffluent total suspended solids (TSS), Roslagsvatten would like to optimize the operation of their dissolvedair flotation (DAF) process and the author was tasked to conduct a study about the subject. The specificaim of the study was to propose one method for optimization with available means to reduce effluentTSS concentration during high flow rates for the present DAF process at Margretelund WWTP.Achieving the aim required an historical analysis of Margretelund WWTP’s DAF process and aninvestigation of the effect influent flow rate and effluent recycle rate (ERR) had on effluent TSSconcentration. The increase of effluent TSS was believed to be caused by increased flow rates frominfiltration and inflow (recorded to 32% of total volume the year 2020) affecting the dissolved air flotation(DAF) process.The literature study design parameters for a dissolved air flotation process, specifically the recycle flowpressurization configuration, generated information about which parameters to take into considerationwhen optimizing a DAF unit. Analysis of historic effluent measurements at Margretelund showed that42% of all samples analysed between January 2015 – January 2021 were below 10 mg/l TSS. Eachhistorical increase of surface load has brought a decreased effluent recycle rate (ERR) and consequentlyan increasing percentage of samples exceeding 10 mg/l. A Pearson correlation presented a negativecorrelation with both ERR and surface load in relation to effluent TSS concentration. This resulted inthe selection of the experimental factors ERR and surface load to be investigated in this study.Margretelunds WWTP’s DAF design of ERR being 10-15% and the design surface load of 4 m/h wasthe base values for the experimental runs. Increases of ERR percentage was done during the experimentfor four different surface loads (2.5, 4, 5 and 6 m/h), with five steps between 15% up to 35% ERR inone of the three parallel DAF units in Margretelund WWTP. TSS in the effluent was constantlymonitored using a TSS sensor. Influent TSS was measured at Roslagsvatten’s accredited laboratory in a24h composite sample with 1 hour for each sub-sample.The results showed that both the highest and the lowest ERR settings tested provided the lowest averageeffluent TSS concentrations. However, a decreased surface load was found to lower effluent TSSconcentration and ERR providing only minor differences within each surface load. Largest surface loadpossible was found to be 5 m/h, for an ERR of 15 or 35%. Surface load less than 5 m/h provided aconcentration under 10 mg/l for all ERR setting. / Margretelund avloppsreningsverk (ARV) placerat i Åkersberga, Stockholms län, byggdes 1956 och drivs av Roslagsvatten AB. Margretelund ARV har sedan 1956 renoverats vid två tillfällen senast 1999. Samma reningsprocess för fysisk, kemisk och biologisk rening har använts sedan senaste renoveringen. Roslagsvatten har haft problem med oönskat tillskottsvatten (motsvarade 32% av total volym 2020) som har påverkat deras flotationsprocess negativt gällande rening av suspenderat material. Detta har till slut lett till förhöjda utsläppsvärden av fosfor som finns bundet i det suspenderade materialet. Denna studie har utförts av författaren på efterfrågan av Roslagsvatten, med syfte att presentera optimeringsåtgärder till styrning av flotationsprocessen vid höga flöden. För att uppnå målet med studien gjordes en historisk analys av Margretelunds flotationsprocess samt undersökningar om hur variationer i inkommande flöde samt recirkuleringsgrad har påverkat koncentration av utgående suspenderat material.Teori undersöktes och information insamlades angående designparametrar gällande optimering av flotationsprocesser, mer specifikt en flotationsprocess med recirkulerat trycksatt flöde för avskiljning av susp. Analys av historiska utsläppsvärden från Margretelund ARV’s flotationsprocess visade på att 42% av proverna analyserade mellan januari 2015-januari 2021 låg under 10 mg/l för utgående suspenderat material. Varje historisk ökning av ytbelastning påvisade en minskande recirkuleringsgrad samt en ökande andel prover som översteg koncentrationen 10 mg/l. Utifrån en Pearson korrelation visades en negativ korrelationen för både ytbelastning och recirkulationsgrad gentemot koncentration av utgående suspenderat material. Både recirkuleringsgrad och ytbelastning valdes därför till denna studies experimentella faktorer. Flotationsprocessen på Margretelund ARV’s var designad för en recirkuleringsgrad på 10–15% vid ytbelastning på 4 m/h, och valdes som basvärde för experimentet. Fem olika grader av recirkulation testades för fyra olika ytbelastningar (2.5, 4, 5 och 6 m/h) i intervallet 15–35% i en av tre parallella flotations bassänger på Margretelund ARV. Koncentration utgående suspenderat material mättes kontinuerligt med en sensor. Inkommande koncentration bestämdes genom ett dygnsprov som analyserades av Roslagsvattens ackrediterade laboratorium.Ett resultat från experimenten var att både den högsta och lägsta inställningen av recirkuleringsgrad visade de lägsta medelvärdena för utgående koncentration av suspenderat material. Dock, visade resultaten att en minskande ytbelastning resulterade i lägre koncentrationer av utgående suspenderat material. Vidare sågs att recirkuleringsgraden enbart hade en låg påverkan på koncentrationerna för varje ytbelastning. Den högsta möjliga ytbelastningen utan att överstiga 10 mg/l visades vara 5 m/h med recirkuleringsgraderna 15% och 35%.

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The design of complex systems such as a launcher, or subsystems like its pressurization system, is known to be fastidious and expensive especially in the space domain. However, the recent emergence of new actors in this domain has been a game changer, binding these systems to fulfil more and more requirements (cheap, efficient, rapidly produced, aesthetic, environmentally friendly…) in order to compete with the market. For these reasons, engineers now need more than ever to consider the full picture of a system or subsystem in order to optimize it. In this context, this document aims to present the method and the results obtained in the optimization of the pressurization system of a reusable rocket first stage named Themis 3. The modelling of the pressurization system has been realized through a software called Geeglee. In order to cover as many impacts of this system as possible, an important part of the rocket stage has been considered and modelled (from the pressurization gases to the propellant tanks, passing by the pressurant and propellant feeding lines). Three High Level Requirements (HLR) have been identified as of major importance for the trade-off in the design of the pressurization system: the total mass impact, the total Recursive Cost (RC) impact and the total Non-Recursive Cost (NRC) impact. This optimization has in particular permitted to confirm some well-known results, so to say that exogenous pressurization systems represent a smaller mass impact on the vehicle, at the expense of a higher RC compared with autogenous systems. / Utformningen av komplexa system, som till exempel en bärraket, eller delsystem som dess trycksättningssystem, är känd för att vara krävande och kostsam, särskilt inom rymdteknikområdet. Den senaste tidens uppkomst av nya aktörer på detta område har dock förändrat spelregler då dessa system tvingas uppfylla allt fler krav (billiga, effektiva, snabbt producerade, estetiska, miljövänliga etc.) kunna vara konkurrenskraftiga på marknaden. Av dessa skäl måste ingenjörer nu mer än någonsin beakta hela bilden av ett system eller delsystem för att kunna optimera det. I detta sammanhang syftar detta dokument till att presentera metoden och resultaten från optimeringen av trycksättningssystemet för en återanvändbar rakets första steg som heter Themis 3. Modelleringen av trycksättningssystemet har genomförts med hjälp av ett systemmodelleringsverktyg som kallas Geeglee. För att täcka in så många effekter av detta system som möjligt har en viktig del av raketsteget beaktats och modellerats (från trycksättningsgaserna till drivmedelstankarna, via tryck- och drivmedelsmatningsledningarna). Tre krav på hög nivå har identifierats som mycket viktiga för avvägningen vid utformningen av trycksättningssystem konstruktion: den totala masspåverkan, den totala icke-rekursiva kostnaden och den totala rekursiva kostnaden. Denna optimering har framför allt gjort det möjligt att bekräfta vissa välkända resultat, dvs. att exogena trycksättningssystem ger en mindre masspåverkan på fordonet, på bekostnad av en högre RC jämfört med autogena system.

A prosthetic socket worn by an amputee must serve a wide variety of functions, from stationary support to the transfer of forces necessary to move. Fit and comfort are important factors in determining the therapeutic effectiveness of a socket. A socket that does not fit the subject well will cause movement problems and potentially long-term health issues. Because a subject's residual limb changes volume throughout the day, it is desirable that the socket adapt to accommodate volume changes to maintain fit and comfort. This thesis presents research to manufacture adaptive sockets using selective laser sintering (SLS). This additive manufacturing process allows freedom to design a socket that has both compliant areas that can adapt to changes to the residual limb, as well as rigid regions to provide necessary support for the limb. A variety of concepts are discussed that are intended for manufacture by SLS, and that feature flexible inner membranes in various configurations. For each concept the membrane will be inflated or deflated to match the limb’s change in volume and the thesis also presents a study to determine SLS machine parameters for optimal build results. A series of experiments was created to understand the ability of SLS manufactured plastics to be inflated and the possible performance. / text

Lors des accidents de la route, les lésions de l’abdomen mettent des vies en jeu et nécessitent un traitement médical long et coûteux. Il est important d’offrir une meilleure prévention des lésions abdominales traumatiques. Des modèles numériques de corps humain ont été développés afin de comprendre les mécanismes lésionnels. L’objectif de cette thèse est de contribuer au développement d’un modèle numérique de foie humain pour la prédiction de lésions hépatiques en cas de choc.Dans un premier temps, une caractérisation morphologique du foie a été réalisée sur 78 scanners et a mis en évidence l’existence de 4 morphotypes. Ensuite, des expérimentations ont mis en évidence l’influence de la pressurisation des vaisseaux sur la déformation de la capsule et ont permis d’identifier la déformation à rupture locale lors d’un choc.Enfin, les modèles numériques des 4 morphotypes identifiés ont été construits pour simuler les essais de décélération réalisés dans la partie expérimentale. / In road accidents, lesions of the abdomen are life-threatening, and require a long and expensive medical treatment. It is important to offer a better prevention of traumatic abdominal injuries. Numerical models of the human body have been developed to understand the mechanisms of injury. The aim of this thesis is to contribute to the development of a numerical model of human liver for the prediction of liver lesions in case of shock.First, a morphological characterization of the liver was performed on 78 healthy patient scanners and highlight the existence of 4 morphotypes.Then, experiments were carried out to highlight the influence of this pressurization of the vessels on the strain state of the Glisson capsule and to identify the local ultimate strain during an impact.Finally, the numerical models of the 4 identified morphotypes were constructed and used to simulate the deceleration tests performed in the experimental part.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-08-15T17:18:32Z No. of bitstreams: 1 2016 - Fernando Morais Rodrigues.pdf: 2322673 bytes, checksum: 8f5b741d438f97ba0f77ff0820d05b50 (MD5) / Made available in DSpace on 2017-08-15T17:18:32Z (GMT). No. of bitstreams: 1 2016 - Fernando Morais Rodrigues.pdf: 2322673 bytes, checksum: 8f5b741d438f97ba0f77ff0820d05b50 (MD5) Previous issue date: 2016-11-25 / The aim of this study was to evaluate the effect of high hydrostatic pressure on physical, chemical, microbiological and sensory characteristics of Minas Frescal cheese produced with reduced sodium content. Initially a literature review was presented on the main techniques used to reduce the sodium content. After identifying the optimal salt concentration of Minas Frescal cheese it was studied the effect of information regarding the excessive salt intake on health towards the consumer preference by means of survival analysis and by the acceptance in structured 9-point hedonic scales. Subsequently it was evaluated the effect of salt concentration and the salting method on production yield, physicochemical composition (moisture, ash, protein, fat), titrable acidity, pH, minerals (sodium and calcium content) and sensory characteristics (hedonic test and check-all-that-apply (CATA) of ?Minas Frescal? cheese. For both the experimental design involved the factorial combination of varying concentrations of sodium chloride (0.2, 1.6 and 3.0%) and salting method (salting and sant in the milk mass). Finally it was investigated the combined effect of pressurizing at different pressures (300, 400 and 500MPa / 5 min) and salt content (40, 70 and 100% NaCl) where 100% of NaCl is equivalent to 1.6% of NaCl content/volume of milk (this content set out in Chapter 3) on the physic-chemical, microbiological and sensorial characteristics (perception of salty taste) of Minas Frescal cheese, by using a complete factorial experimental design 2^2 with triplicate at the midpoint. From the data collected parametric models were obtained allowing the estimation of the optimum salt concentration: 3.2 +/- 0.4 (%NaCl). For the cheese with such salt concentration it was obtained 21.5% of consumer rejection, of which 8.3% for considering the Minas Frescal cheese of being "little salty" and 13.2% for considering it ?too salty?. Information on the health hazards due to excessive sodium intake was not significant (p>0.05) for the consumers. Either the effect of salt concentration and/or method of salting either individually or their interaction resulted in significant differences for the parameters moisture, ash, protein and minerals (p<0.05). The salt concentration showed the highest influence on the response variables evaluated in this study. The yield statistically varied among the treatments (p<0.05), and was influenced by the level of sodium, while calcium concentration and also the yield were affected by the salting method, salt concentration and interaction of the parameters (p<0.05). The yield values for different treatments were statistically different (p<0.05). With respect to the sensory analysis the salting methods influenced the acceptance only for the cheeses elaborated with 3.0% NaCl (p<0.05). Salt concentration (1.6%) for both salting methods achieved the highest average acceptance. Significant differences for the physical and chemical microbiological and sensory parameters (p < 0.05) were observed. The physical-chemical response variables more influenced by the treatments were: sodium content, calcium content, NaCl content, salt content, moisture, DPPH, proteolysis and antihypertensive activity. Higher levels of pressure and salt content resulted in further reduction in the microbial population. Bioactive properties (antihypertensive activity and antioxidant activity) of the Minas Frescal cheese was confirmed by the analyses. Regarding the sensory analysis no increase in the perception of salty taste occurred due to the high pressure treatments evaluated. / O objetivo do presente estudo foi avaliar o efeito da Alta Press?o Hidrost?tica sob as caracter?sticas f?sico-qu?micas, microbiol?gicas e sensoriais em queijo Minas Frescal produzido com teor reduzido de s?dio. Inicialmente apresentou-se uma revis?o de literatura sobre as principais t?cnicas utilizadas na redu??o do teor de s?dio. Ap?s, identificou-se a concentra??o ?tima de sal no queijo Minas Frescal e avaliou-se o efeito da informa??o sobre os malef?cios do consumo excessivo de sal ? sa?de na prefer?ncia do consumidor pelo produtos, por meio de an?lise de sobreviv?ncia e teste de aceita??o em escala hed?nica estruturada de nove pontos. Posteriormente, abordou-se o efeito da concentra??o de sal e o m?todo de salga sob o rendimento, composi??o centesimal (umidade, RMF, prote?na, gordura), acidez total, pH, minerais (s?dio e c?lcio) e caracter?sticas sensoriais com base em teste hed?nico de aceita??o e Check All That Apply (CATA) do queijo Minas Frescal. Para tanto, o delineamento experimental compreendeu a combina??o fatorial das vari?veis concentra??o de cloreto de s?dio (0,2; 1,6 e 3,0%) e m?todo de salga (salga no leite ou salga na massa. Por ?ltimo, investigou-se o efeito combinado da pressuriza??o (300, 400 e 500MPa / 5 min) e teores de sal (40, 70 e 100% NaCl) onde 100% de NaCl foi equivalente ao teor de 1,6% de NaCl /volume de leite (teor este definido no Cap?tulo 3) sob as caracter?sticas f?sicoqu?micas, microbiol?gica e sensorial (percep??o do gosto salgado) do queijos Minas Frescal, empregando-se delineamento experimental fatorial completo 2^2 com triplicata no ponto central. A partir dos dados processados, foram obtidos modelos param?tricos que permitiram estimar a concentra??o ?tima de sal para os queijos: 3,2 +/- 0,4 (%NaCl). Para esta concentra??o, houve 21,5% de rejei??o por parte dos consumidores, dos quais 8,3% por o queijo frescal estar ?pouco salgado?, e 13,2% de rejei??o por estar ?muito salgado?. A informa??o sobre os malef?cios ? sa?de do consumo excessivo de s?dio n?o foi significativo (p>0,05). J? para o efeito da concentra??o de sal e/ou m?todo de salga, foram observadas diferen?as significativas para os par?metros umidade, cinzas, prote?na e minerais (p<0,05). A concentra??o de cloreto de s?dio (%) apresentou maior influ?ncia sobre as vari?veis de resposta avaliadas. Os valores de rendimento para os diferentes tratamentos diferiram estatisticamente (p<0,05). O teor de s?dio, c?lcio e o rendimento foram afetados pelo m?todo de salga, concentra??o de sal e intera??o de ambos (p<0,05). Com rela??o ? an?lise sensorial, os m?todos de salga influenciaram a aceita??o apenas para os queijos elaborados com 3,0% de NaCl (p<0,05). Concentra??o intermedi?ria deste sal (1,6 %) para ambos os m?todos de salga alcan?aram as maiores m?dias de aceita??o. Para o efeito da Alta Press?o hidrost?tica,diferen?as significativas para os par?metros f?sico-qu?micos (p<0,05), microbiol?gicos e sensoriais foram observadas. As vari?veis de resposta f?sico-qu?micas mais influenciadas pelos tratamentos foram: s?dio, c?lcio, NaCl, %NaCl na umidade, atividade antioxidante, prote?lise e atividade antihipertensiva. Maiores n?veis de press?o e teor de sal resultaram em maior redu??o do n?mero de microrganismos analisados, conforme preconizado pela legisla??o. Propriedades bioativas (Atividade anti-hipertensiva e Atividade antioxidante) foram confirmadas atrav?s das an?lises realizadas. Com rela??o ? an?lise sensorial, n?o houve aumento da percep??o do gosto salgado para os tratamentos avaliados.

The objective with this thesis is to build a Black-Box model of the tank pressurization system in JAS 39 Gripen. This model is intended to be used in an existing diagnosis system for the security control in the tank pressurization system. The tank pressurization system is a MIMO system. This makes the identification process more complicated when the best model is to be chosen. In this master's thesis the identification procedure for a MIMO system can be followed. Testing of the diagnosis system with the created Black-Box model shows that the model seems to be good enough. The diagnosis system takes the right decisions in the performed simulations. This shows that system identification might be a good alternative to physical modelling for a real-time model. The disadvantage with the Black-Box model is that it is less accurate in steady-state than the physical model used before is. The advantage is that it is faster than the physical model. The diagnosis system and the model developed in this thesis are not directly applicable on the real system today. The model has to be redesigned on the real system, this is also the case for the diagnosis system. The diagnosis system also has to be redesigned, so general flight cases, not only the security control can be supervised. However, experiences and choices like input and output signals, and choice of sample interval can be reused from this thesis when a new model might be developed.

<p>The objective with this thesis is to build a Black-Box model of the tank pressurization system in JAS 39 Gripen. This model is intended to be used in an existing diagnosis system for the security control in the tank pressurization system. The tank pressurization system is a MIMO system. This makes the identification process more complicated when the best model is to be chosen. In this master's thesis the identification procedure for a MIMO system can be followed. Testing of the diagnosis system with the created Black-Box model shows that the model seems to be good enough. The diagnosis system takes the right decisions in the performed simulations. This shows that system identification might be a good alternative to physical modelling for a real-time model. The disadvantage with the Black-Box model is that it is less accurate in steady-state than the physical model used before is. The advantage is that it is faster than the physical model. The diagnosis system and the model developed in this thesis are not directly applicable on the real system today. The model has to be redesigned on the real system, this is also the case for the diagnosis system. The diagnosis system also has to be redesigned, so general flight cases, not only the security control can be supervised. However, experiences and choices like input and output signals, and choice of sample interval can be reused from this thesis when a new model might be developed.</p>