Made available in DSpace on 2016-04-18T21:36:01Z (GMT). No. of bitstreams: 2 Douglas Marquezin Felippe1.pdf: 1519362 bytes, checksum: 40709b1c88a4aa5d83632f3034ffa9cf (MD5) Douglas Marquezin Felippe2.pdf: 3740401 bytes, checksum: c124e8cef0b0b36e025714367db7c937 (MD5) Previous issue date: 2010-02-23 / Fundo Mackenzie de Pesquisa / Heat treatment processes are related to control heating and quenching with the aim of improving physical properties, such as: hardness, abrasion resistance, toughness, among others. During the heat treatment process, the quenching media are of great importance steps, because it extracts heat from the part with the achieve of obtaining specification properties. However, the hardening process causes undesired distortion that can be related to the permanent residual stress in the parts, generated during quenching. Some conventional hardening heat treatments do not have the control of the position during quenching, this control is usually applied in induction heat treatment, improving the homogeneity of heat exchange in the quenching process, suggesting lower distortion. The induction process can be a sustainable one, because the heating is applied just in the part. This survey compared both metallurgical and mechanical properties between two heat treatment processes of DIN 100Cr6 steel bearings: conventional and induction. With the result of this survey, it is intended, to change the conventional heat treatment process for the induction process in bearing manufacturing, with the objective of reducing the typical out-of-roundness from the conventional heat treatment process, and a reduction the bearing manufactured costs. / A têmpera compreende operações de aquecimento e resfriamento controlado, que objetivam melhorias nas propriedades físicas como dureza, resistência à abrasão, tenacidade entre outras. Durante o processo de têmpera, o meio de resfriamento é uma das etapas mais críticas, pois extrai calor da peça com o objetivo de obter as propriedades desejadas. Porém, o processo de têmpera gera deformações não desejadas, que podem estar relacionadas às tensões residuais que ficam permanentes na peça, introduzidas durante o resfriamento. Alguns tratamentos térmicos de têmpera convencional não têm controle da posição da peça durante o resfriamento. Este controle é normalmente utilizado em processos de têmpera por indução, melhorando a homogeneidade da extração de calor durante o resfriamento, sugerindo menores índices de deformação. O processo por indução pode ser considerado sustentável, pois o aquecimento é localizado apenas no componente. Este trabalho comparou as propriedades metalúrgicas e mecânicas entre dois processos de têmpera de rolamentos do aço DIN 100Cr6: convencional e por indução. Como resultado deste trabalho, pode-se substituir o tratamento térmico com aquecimento convencional pelo tratamento térmico com aquecimento por indução para a manufatura de rolamento, com objetivo de redução da deformação de ovalização característica do processo de tratamento térmico convencional.

Magister Psychologiae - MPsych / Cape Town is suffering from high rates of alcohol and other drug (AOD) problems. Despite the need for effective treatment, there are insufficient AOD treatment facilities available, with barriers to AOD treatment being particularly pronounced among historically disadvantaged communities (HDCs). In addition, the high drop-out rate of patients from AOD treatment, and the finding that retention in treatment is predictive of positive outcomes, increases the necessity of retaining people who enter AOD treatment.This study therefore aimed to identify those patient-level factors impacting on the successful completion of and retention in AOD treatment. In particular, the study aimed to describe the relationship between treatment process factors (therapeutic alliance,motivation, treatment satisfaction, social support), demographic and psychological variables, and treatment completion and retention. The Texas Christian University (TCU) Treatment Model, which conceptualises the AOD treatment process, provided the theoretical framework for the study. Using a quantitative design, secondary data analysis was conducted on a section of data that was originally collected by the Medical Research Council (MRC) via a cross-sectional survey. The sample consisted of 434 individuals from HDCs who had previously entered AOD treatment. Multiple regression analyses revealed that the therapeutic alliance, treatment satisfaction, abstinence-specific social support and depression were significant predictors of treatment completion, while race,therapeutic alliance, abstinence-specific social support and anxiety were predictive of the time spent in treatment. These predictors were positively associated with treatment completion and time in treatment. Black Africans spent significantly less days in treatment than Coloured individuals, although both groups were equally likely to complete treatment. The results suggest that by strengthening the therapeutic alliance,social support and treatment satisfaction, treatment completion and retention can be improved. This can be achieved by training, ongoing monitoring of these factors during treatment, and greater involvement of supportive social networks in a patient’s recovery. The findings also point towards the need for improved service delivery for Black Africans, who confront many barriers to accessing inpatient AOD treatment.

The onset and development of addiction in people with ADHD (Attention Deficit Hyperactivity Disorder) can be predicted by various factors. An essential factor linking the comorbidity of ADHD and the risk of developing substance abuse is increased vulnerability due to neuropsychological deficits and a wide range of biopsychosocial problems that occur from childhood to adulthood. The occurrence of dual diagnoses in substance users treated in residential treatment in therapeutic communities has a major impact on intrapsychic and interpersonal abilities, cognitive and executive functions, and on the ability to manage a treatment program primarily intended for clients without comorbid load. Current research on ADHD in substance users points to a high prevalence of ADHD associated with specific treatment complications and an increased drop-out rate. The aim of the monothematic dissertation, which is based on the results of pre-research and main research project (Study I. - IV.), Is an overview of key findings in terms of ADHD prevalence, ADHD diagnosis in therapeutic communities, treatment complications and gender specifics in treatment and overview. main findings on the development of motivation and specific needs of clients with ADHD. The output of the dissertation is a summary of outputs and...

There is a current lack of accurate tools to determine the concentration of cyanobacteria in situ.  Besides, cyanobacterial blooms have to be carefully monitored in reservoirs as they are more frequent because of climate change and can lead to potential released of toxins, along with other components. This project investigates the possible use of fluorescent probes to measure the concentration of different types of organic matter released by the algae. Three different species of toxic cyanobacteria were chosen to carry out this research as they are representative of the local harmful blooms found across Australia. Furthermore, the efficiency of two different chemicals (powdered activated carbon, also known as PAC, and alum) used in drinking water treatment plants were investigated, in order to determine a method for automatic dosage adjustment in water treatment plant. The organic matter was characterized by LC-OCD and fluorescence spectroscopy and statistical analysis such as principal component analysis was performed on the generated data. General characterization of the different species was firstly performed and globally, similar comportments were observed among the three cyanobacteria species. There is indeed a general increase in the release of organic material throughout the cell’s growth phase. Results from the jar tests showed that PAC mainly targeted humic-like substances and building blocks, which are middle size particles. The average removal rate obtained was 40µg/L per mg/L of PAC added into the water. Therefore, there is indication that the decreased efficiency for the removal of the taste and odor compounds observed in certain plants can be partially attributed to direct competition of organic matter adsorption onto PAC instead of a blockage of the PAC pores by larger particles. On the other hand, alum was able to remove large particles, particularly biopolymers and also humic-substances. However, a great increase of the low molecular weight molecules at very high doses of alum was seen, which suggest that a too high dose of alum is toxic for the algae cells. Based on the bench scale testing the recommended dose of 50 mg/L seems to be optimum for the studied water treatment plant. Specific ultraviolet absorbance and dissolved organic carbon measurements were also investigated and good correlations were found between the concentration of humic-like substances and absorbance, confirming that they are good measure to assess the content of organic matter in the water. However, as the slope coefficient of the linear trend varied between the species, it was not possible to obtain a common conversion factor for all the species. Finally, one fluorophore was found in common to all the samples and is characterized by the excitation-emission wavelength: 240/440 nm. Correlations with the chromatography’s results were investigated and this component seems to match the biopolymers and humic-like substances concentrations. Furthermore, its intensity decreases continuously with the addition of PAC whereas a drop was observed at the lower doses of alum. In regards on these findings, a method for automatic chemicals dosing from the fluorescence measures was proposed. / Detta examensarbete handlar om hur dricksvattenkvalitet kan kontrolleras och övervakas i vattenreningsverk. Nu existerar  inte någon exakt metod för att bestämma koncentrationen av cyanobakterier i vatten då det finns många olika arter. Men det är viktigt att övervaka algers tillväxt in i vattenreningsverk för de kan släppa ut skadliga ämnen till dricksvattnet. De tre arter som studerats i detta projekt är giftiga. Det organiska materialet i råvattnet kan också blockera membranporer eller leda till n biprodukter, som är cancerframkallande. Till sist konkurrerar några organiska substansen med smak- och luktföreningar för adsorptionsställena hos det pulverformiga aktiverade kolet. Därför är smaken och luktföreningarna inte väl borttagna, vilket leder till kundernas klagomål. Cyanobakterier måste övervakas noggrant.                            För att bestämma biologisk och kemisk egenskap hos vatten används flera tekniker för närvarande. I examensarbetet har undersökningar med vätskekromatografi och fluorescensteknik företagits. Kromatografi användes för att klassificera den organiska substansen i mindre grupper: biopolymerer, humus substanser, byggstenar och neutralmolekyler med låg molekylvikt (LMVN). Statistisk analys med R, inklusive huvudkomponentanalys företogs på insamlade data. Fluorescensdata registrerades också och visas i en excitationsutsläppsmatris.                            Experimenten reproducerade en behandlingsprocess och undersökte effektiviteten hos två kemikalier: pulveriserat aktivt kol (PAK) och alun. Resultaten visade att humusämnen   och dess byggstenar var väl borttagna av PAK medan även biopolymerer och humusämnen var väl bortagna av alun. Emellertid var en för hög dos av alun skadlig eftersom det ledde till en ökad frisättning av LMVN. I synnerhert kunde PAK ta bort 40µg/L av både humusämnen och dess byggstenar per mg/L av PAK tillagd. Det föreslår att de är de viktigaste konkurrenterna och att endast direkt konkurrens för adsorptionsställena sker. Om det fanns blockeringsfenomen, skulle det också finnas en minskning för biopolymererna. Den optimala doseringen av alun som bestämdes för det undersökta vattenreningsverket var 50 mg/L. Det kunde ta bort 60-70% av biopolymerer och 40-50% av humusämnen.                            Specifik ultraviolett absorbans och fluorescens registrerades. Båda visade riktigt bra korrelationer med humusämnen, vilket gör de till bra verktyg för att bedöma vattenkvaliteten. Men det kräver fortfarande att arten av cyanobakterie urskiljs eftersom koefficientens lutningar var olika. De kan därför vara ett verktyg för att mäta koncentrationen av organisk material, men arten måste vara känd. Fluorescencedata visade en topp vid 440 nm. En parallellfaktoranalys utfördes på data och endast en komponent hittades gemensam i alla prover. Därför studerades den maximala fluorescensintensiteten hos denna komponent. Å ena sidan kunde vi observera en kontinuerlig minskning av intensiteten när PAK tillsattes. Det är därför möjligt att veta hur man justerar den kemiska doseringen från fluorescensintensiteterna. I slutet av examensarbetet föreslås en metod för automatisk kemisk dosering. Fluorescensprober kan ännu inte exakt indikera cellkoncentrationen. Men med flera sonder som riktar sig till olika våglängder kan de redan vara till stor hjälp för styrning vid vattenverk.

Aerated treatment wetlands are an increasingly recognized nature–based technology for thetreatment of domestic and industrial wastewater. As biodegradation is the most importanttreatment mechanism in aerated wetlands, these systems heavily rely on mechanical aerationmediated oxygen transfer to supply the dissolved oxygen demand of the associated microbialcommunity. In the last decade, research on aerated wetlands has evolved, however, majorquestions on aeration, the associated oxygen transfer and the quantitative link to treatmentperformance still remain unknown. Answering these questions can further improve aeratedwetland design to optimize treatment efficacy and economical efficiency. This dissertation investigated the link of oxygen transfer to the air flow rate of aerationand elucidated the associated impact on treatment performance for organic carbon and nitrogenin horizontal flow aerated wetlands. Therefore, a numerical process model includingone dimensional reactive transport was developed. This model describes the main processesinvolved in horizontal flow aerated wetlands: water flow, heat transport, transport of solubleand particulate wastewater pollutants, biodegradation by a network of bacterial communitiesand oxygen transfer through mechanical aeration. For model calibration and validation, pilot–scale experiments in horizontal flow aerated wetlands treating real wastewater were conducted.These included conservative tracer experiments as well as monitoring steady–state operationat variable air flow rates and aeration interruption. In general, the model was able to simulate conservative tracer transport as well as treatmentperformance for organic carbon and nitrogen at steady–state operation and aeration interruptionwith sufficient accuracy. A local sensitivity analysis of the calibrated parameters revealedporosity, hydraulic permeability and dispersion length as well as the oxygen transfer coefficientkLa as most important. When operating the wetland systems at steady–state, aeration provideda mostly aerobe environment, except at the influent zone. However, when aeration wasinterrupted, anaerobe process started to take over and treatment performance declined within3–4 days. The modeling elucidated that methanogenic and sulphate reducing bacteria can playa significant role for organic carbon removal during aeration interruption. Moreover, the modelrevealed a non–linear declining relationship of the air flow rate with oxygen transfer coefficientkLa and of kLa with treatment performance. The alteration of oxygen transfer by wastewaterpollutant concentration was then investigated in a laboratory–scale column experiment. Basedon this experiment, an empirical equation describing the inhibitory effect of soluble chemicaloxygen demand (CODs) on the oxygen transfer coefficient kLa was derived and incorporatedinto the process model. With the extended model several simulation scenarios were analyzedto quantify the impact of the inhibited oxygen transfer on treatment performance. It turnedout that the reduction of oxygen transfer by CODs will, most likely, be relevant only at highinfluent wastewater strength (CODs 300 mg L-1), low aeration (air flow rate 50 L m-2h-1) or when the aerated wetland design includes zoned aeration. With respect to secondarytreatment of domestic effluents at similar strength using a spatially uniform aeration, an airflow rate of approximately 150–200 L m-2 h-1 can be recommended as a reasonable compromisebetween treatment efficiency and robustness. If zoned aeration is intended (e.g. to create a redox zonation), however, the air flow rate should be increased to approximately 400 L m-2 h-1 to supress the inhibition of oxygen transfer by CODs concentration. Furthermore, the air flow rate at steady–state operation (50–500 L m-2 h-1) did not substantially affect the response in effluent concentrations for organic carbon and nitrogen. This means that at steady–state air flow rates of 50–500 L m-2 h-1 operation, treatment efficacy during aeration interruption will deteriorate and recover in a similar time. In conclusion, this dissertation provides quantitative insights into the mechanisms of aeration and treatment performance for organic carbon and nitrogen in horizontal flow aerated treatment wetlands. The findings obtained can support aerated treatment wetland design for research experiments and engineering applications. Therefore, this dissertation represents a significant advancement in the field of aerated treatment wetland research.

L’objectif de ce travail est d’une part (i) étudier le comportement de la biomasse notamment la production d’EPS en présence des composés pharmaceutiques (un agent anticancéreux et cinq antibiotiques); et d’autre part, (ii) étudier les EPS dans le contexte de décantation des boues en présence d’agents fongiques et en situations réelles dans des stations d’épuration. L’étude en présence de l’agent anticancéreux a été réalisée dans des bioréacteurs à membranes. La présence de l’agent anticancéreux a induit l’augmentation de la production d’EPS agissant comme un mécanisme de protection microbienne qui était à l’origine du colmatage des membranes. L’effet de cinq antibiotiques a été évalué en réacteur batch. La famille des macrolides a montré un effet plus important sur l’activité microbienne avec une augmentation significative de la production d’EPS associée à un mécanisme de protection. La décantation des boues en présence des cultures fongiques a été conduite en réacteur pilote. Une amélioration spectaculaire de la décantation a été liée à une meilleure cohésion au sein des flocs imputable en grand partie à l’augmentation de la production d’EPS. Enfin, le diagnostic du procédé de traitement des eaux a été établi sur trois stations d’épuration des papeteries grâce à une double approche d’une part l’analyse physico-chimique des boues et d’autre part, l’exploitation statistique d’analyse en composantes principales (ACP) des paramètres technologiques enregistrées dans chaque station. Nous avons tenté d’exprimer sous forme de régressions linéaires ou polynomiales de deuxième degré, la décantation en fonction d’une quantité réduite des paramètres mesurés / The objective of this work is firstly, i) to study the microbial behaviour of the biomass especially the production of the EPS in the presence of pharmaceutical compounds (an anticancer product and five antibiotics); and secondly, ii) to study EPS in the context of the sludge settling in wastewater treatment plants. The study in the presence of the anticancer product was done in membrane bioreactors. The presence of the anticancer product provoked the production of the EPS as the protection mechanism which is at the origin of the membrane fouling.The effect of five antibiotics was evaluated in batch reactors. The family of macrolides showed the most important effect on the microbial activity with a significant increase of the EPS production which was associated with a protection mechanism.Sludge settling in the presence of fungi was carried out in a pilot reactor. The spectacularly improvement of the sludge settleability was related with a better cohesion inside of the flocs attributed to an increase of the EPS production.Finally, the diagnosis of different wastewater treatment processes was established in three paper mill wastewater treatment plants thanks to the double approach used here, the physico-chemical analysis of the sludge and the statistical analysis by principal components analysis of the different parameters recorded in each plant. We tried to describe the parameter related to the settling behaviour by linear or polynomial regressions of second degree in function of a reduced number of the measured parameters

Les systèmes réels sont généralement de nature non-linéaire, et leurs modélisations etsurveillance restent une tâche difficile à accomplir. Néanmoins, avec les progrès technologiqueson dispose maintenant d'un atout de taille sur ces systèmes qui est les données.Ce travail présente une technique de diagnostic de défaut et de modélisation basée en grandepartie sur la méthode d'apprentissage automatique « Les Machines à Vecteurs de Support,SVM » qui est basée sur les données. La méthodologie proposée est appliquée à différentessystèmes multivariables et non linéaires, à savoir : un procédé de traitement des eaux usées, unsystème éolien et un réacteur chimique parfaitement agité.L'objectif de cette thèse de doctorat est d'examiner la possibilité d'extraire le maximumd'information à partir de données afin de surveiller efficacement le comportement de systèmesréels et de détecter rapidement tout défaut qui peut compromettre leur bon fonctionnement. Lamême méthode est utilisée pour la modélisation des différents systèmes. Plusieurs défis ont étérelevés tels que la complexité du comportement des systèmes, le grand nombre de mesuresvariant à différentes échelles de temps, la présence de bruit et les perturbations. Une méthodegénérique de diagnostic de défauts est proposée par la génération des caractéristiques de chaquedéfaut suivie d’une étape d'évaluation de ces caractéristiques avec une amélioration du transfertde connaissances en modélisation.Dans cette thèse ont a démontré l'utilité de l'outil Machines à Vecteurs de Support, enclassification par la construction de modèles de décision SVM dédiés à l'évaluation descaractéristiques de défaut, et aussi en tant qu'estimateur non linéaire/ou pour la modélisation parl'utilisation des machines à vecteurs de support dédiés pour la régression (SVR).La combinaison de SVM et d’une méthode basée sur le modèle "observateur" a été aussi étudiéeet a été nécessaire dans certains cas pour garantir un bon diagnostic de défauts. / Real systems are usually nonlinear and their modeling and monitoring remains adifficult task. However, with advances in technology and the availability of big amounts of data,we have a facility to operate these systems.This work presents a methodology for fault diagnosis and modeling which is in large part basedon the method of Support Vector Machines (SVM) which data-based. The proposedmethodology is applied to various nonlinear multivariable systems including: wastewatertreatment processes, wind turbines and stirred tank reactors.The objective of this PhD is to examine the possibility of extracting the maximum of informationfrom data to effectively monitor the behavior of real systems and rapidly detect any faults whichmay impair their proper functioning. The same method is used for modeling the differentsystems. Several challenges were identified and surmounted such as the complexity of thesystem behavior, large amount of data varying at different time scales, the presence of noise anddisturbances. A generic method of fault diagnosis is proposed for the generation of the faultcharacteristics followed by an evaluation of these characteristics as well as an improved transferof knowledge in modeling.In this thesis the usefulness of the tool Support Vector Machines in Classification has beendemonstrated by the construction of decision models dedicated to evaluating the characteristicsof faults, and also its usefulness for modeling/ or as estimator for the nonlinear systems usingsupport vector machines dedicated for regression (SVR).The combination of SVM and a method based on models “observer” was also considered andwas found to be interesting in some cases to ensure proper fault diagnosis.