Dissertations / Theses on the topic 'Selective filtration'

Mestrado em Biotecnologia - Biotecnologia Alimentar
The present study proposes the development of electrospun fibrous membranes with high selectivity and affinity for patulin retention throughout the apple juice clarification process. Nanostructured bi- and tridimensional materials can be obtained by electrospinning with very large surface-to-volume ratio, high porosity and interconnectivity, making them very attractive for a large number of applications including separation processes. Other remarkable methodology is the molecular imprinting. This is a technique that creates molecularly imprinted cavities with memory capacity from the interaction between a template molecule and a functional monomer or polymer segment for binding specific target molecules. The main objective of this work is the development of new nanofibrous membranes with affinity and performance to remove patulin from apple juice during its processing. The strategy implemented to reach the proposed objective combines molecular imprinting and electrospinning processes. The main polymer poly(ethylene terephthalate) (PET) was blended with chitosan (Chi) and polyallylamine (PAA) to constitute the base of electrospun membranes. The patulin analogs, 6-hydroxynicotinic acid and 5-indanol, were used as template molecules for molecular imprinting and thereby enhance retention capacity of the non-woven electrospun fibrous membranes. The clean-up of patulin analogs reached retention levels of 10 % by PET-Chi membranes and 80 % by PET-PAA membranes. Furthermore, the PET-Chi membranes demonstrated high stability and improved mechanical properties when compared with those of PET alone and good performance as a filter for juice clarification.
O presente estudo propõe o desenvolvimento de membranas nanofibrosas com elevada afinidade e seletividade para a retenção de micotoxinas durante o processo de clarificação do sumo de maçã. Através de electrofiação obtém-se nanomateriais bi- e tridimensionais com alto rácio superfície-volume, elevada porosidade e interconectividade, características que potenciam a aplicação destes materiais em inúmeras áreas incluindo em processos de separação. Outra metodologia aplicada neste estudo foi a impressão molecular. Esta técnica permite a criação de cavidades molecularmente impressas a partir da interação entre a molécula molde e o monómero ou polímero funcional para a ligação especifica de determinada molécula alvo. O principal objectivo deste trabalho é o desenvolvimento de novas membranas com afinidade e performance para a remoção da patulina durante o processamento do sumo de maçã. As estratégias implementadas para alcançar este propósito combinam os dois processos anteriores: electrofiação e impressão molecular. O polímero poli(etileno tereftalato) (PET) serviu de base para a formação da membrana fibrosa por electrofiação, na qual foram incorporados outros polímeros como a quitosana (Q) e a polialilamina (PAA). Por sua vez, os análogos da patulina - ácido 6- hidroxinicotinico e 5-indanol - foram usados como moléculas molde para a impressão molecular de modo a aumentar a capacidade de retenção das membranas nanofibrosas. Deste modo, foram alcançados níveis de retenção dos análogos da patulina de 10 % para as membranas PET/quitosana e de 80 % para as membranas PET/PAA. Para além disso, as membranas PET/quitosana demonstraram elevada estabilidade com melhoria das propriedades mecânicas face à membrana de PET e também apresentaram boa performance como filtro para a clarificação do sumo de maçã.

The preferential grazing of an organism on certain particles from the environment (selective feeding) impacts particle compositions and distributions in aquatic systems. Historically, selective feeding has been examined almost exclusively through the lens of particle size. In this dissertation, I investigated size-based selection alongside particle shape, adhesive interactions, and the mechanical operation of the filter to characterize the selective-feeding capabilities of marine mucous-mesh filter-feeders (the planktonic appendicularian Oikopleura dioica and the benthic ascidians Herdmania momus and Styela plicata). I used high-speed videography to describe the feeding-filter mechanics of O. dioica and tested its capacity for size-based particle selection. I show for the first time how pulsatile flow coupled with elasticity of the filter facilitates prey detachment. Using synthetic beads, I showthat the food-concentrating filter selectively retains smaller particles because of their increased adhesion. Appendicularian houses may therefore retain particles size-selectively, which counters the historically-held assumption that appendicularians are non-selective grazers. I synthesized ellipsoidal microbeads to test the effect of particle length-to-width ratios on the capture efficiency of O. dioica and S. plicata. Both grazers retained ellipsoidal particles according to their minimum diameter. I identified the kinematic mechanism for retention patterns of ellipsoidal particles using high-speed videography and endoscopy of particle interactions with the mucous filters of O. dioica and H. momus, respectively. In the filters of both animals, ellipsoids oriented parallel to fluid streamlines and the minimum dimension of the particle intercepted the filters. I provide the first mesh-scale observations of particle capture by H. momus, show how particle shape influences hydrosol filtration by S. plicata, and suggest that ascidian filtration may not be adequately described by simple sieving.

Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 37-39).
Sepsis kills millions of people worldwide each year and occurs when microorganisms enter the bloodstream of an infected host. The presence of microorganisms in the bloodstream triggers the body to produce many inflammatory proteins, known as cytokines, that cause damage to blood vessels and vital organs. This leads to capillary leak, failing organs, and often death. We have developed a novel approach to modulate the inflammatory response, using antibody-modified conduits (AMCs) to filter harmful cytokines selectively from the circulation and in a time-specific manner. Here, we characterize variables that affect AMC performance to determine optimal AMC conditions for later use downstream.
by Morgan K. Moroi.
S.B.

Les hydrogels sont des matériaux polymères hydrophiles qui retiennent de grandes quantités d’eau tout en conservant une structure tridimensionnelle, ce qui les rend adaptés à des applications biomédicales et de filtration. Ce manuscrit se concentre sur les membranes d’hydrogels fabriquées à partir de polyéthylène glycol diacrylate (PEGDA) réticulé par UV en présence de chaînes de polyéthylène glycol (PEG) et d’un photoamorceur. Les membranes PEGDA/PEG sont sélectionnées pour leur robustesse mécanique et leur perméabilité élevée qui peut être ajustée en fonction de la concentration et de la masse molaire du PEG. Une caractéristique importante de ces membranes est que les chaînes de PEG restent piégées dans la matrice, permettant ainsi de les fonctionnaliser pour une filtration sélective. Notre étude montre que les membranes PEGDA/PEG peuvent retenir sélectivement de petites molécules formant des liaisons hydrogène. Nous fonctionnalisons également les membranes avec de l’acide polyacrylique (PAA) pour les rendre sélectives aux colorants chargés positivement. Les membranes PEGDA/PEG/PAA s’avèrent efficaces pour la rétention du bleu de méthylène et de la rhoda- mine B. La sélectivité de ces membranes est réversible par ajustement du pH, permettant ainsi de les rincer et de les réutiliser. L’analyse structurelle des membranes par diffusion de neutrons aux petits angles (SANS) révèle que les chaînes de PEG conservent une structure gaussienne dans la matrice de PEGDA, mais avec des rayons de giration et des longueurs de corrélation plus élevés qu’en solution, suggérant des contraintes topologiques comme des greffages chimiques ou des enchevêtrements. Une observation clé est que le rapport surface/volume de la matrice de PEGDA diminue avec l’ajout de PEG, indiquant la formation de cavités plus grandes, ce qui explique l’augmentation de la perméabilité observée. Lorsque la concentration en PEG dépasse une certaine valeur critique (C∗), le rapport surface/volume augmente, suggérant une diminution de la taille des cavités d’eau et, par conséquent, de la perméabilité. Nous développons également un modèle théorique pour prédire la perméabilité des hydrogels PEGDA/PEG en fonction de la masse molaire et de la concentration en PEG pour C < C∗, qui correspond bien aux mesures expérimentales
Hydrogels are hydrophilic polymer materials that retain large amounts of water while maintaining a three- dimensional structure, making them suitable for biomedical and filtration applications. This manuscript focuses on hydrogel membranes made from polyethylene glycol diacrylate (PEGDA) crosslinked by UV in the presence of polyethylene glycol (PEG) chains and a photoinitiator. PEGDA/PEG membranes are selected for their me- chanical robustness and high permeability, which can be adjusted based on the concentration and molecular weight of PEG. An important feature of these membranes is that the PEG chains remain trapped in the ma- trix, allowing them to be functionalized for selective filtration. Our study shows that PEGDA/PEG membranes can selectively retain small molecules forming hydrogen bonds. We also functionalize the membranes with polyacrylic acid (PAA) to make them selective for positively charged dyes. PEGDA/PEG/PAA membranes prove effective in retaining methylene blue and rhodamine B. The selectivity of these membranes is reversible by adjusting the pH, allowing them to be rinsed and reused. Structural analysis of the membranes by small- angle neutron scattering (SANS) reveals that the PEG chains maintain a local gaussian structure within the PEGDA matrix, but with larger radii of gyration and correlation lengths than in solution, suggesting topolo- gical constraints such as chemical grafting or entanglements. A key observation is that the surface-to-volume ratio of the PEGDA matrix decreases with the addition of PEG, indicating the formation of larger cavities, which explains the observed increase in permeability. When the PEG concentration exceeds a certain critical value (C∗), the surface-to-volume ratio increases, suggesting a decrease in the size of the water cavities and consequently in permeability. We also develop a theoretical model to predict the permeability of PEGDA/PEG hydrogels as a function of the molecular weight and concentration of PEG for C < C∗, which corresponds well with experimental measurements

The Best MPhil Thesis in the Faculties of Dentistry, Engineering, Medicine and Science (University of Hong Kong), Li Ka Shing Prize,2003-2005
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Surgery
Master
Master of Philosophy

This thesis is concerned with internal redox reactions of metal complexes and the application of such reactions in the selective filtration of tobacco smoke. The reactions of Fe(II), Fe(III) and Cu(II) quinoneoximic complexes and of some other complexes of these metals with Lewis bases (e.g. Ph3P and py) have been investigated. From the results obtained and from a critical consideration of analogous reactions reported in the literature the behaviour of metal chelates towards Lewis bases has been assessed. It has been established that the reaction between a metal chelate and a Lewis base may lead to: (i) Adduct formation, (ii) condensation and (iii) to an internal redox reaction, M(chel)n LB[over arrow] M(chel)n-1(LB)x + chel* The latter is favoured when the metal in M(chel)n has a stable lower oxidation state, by Lewis bases capable of E[eta]—bonding and by chelating ligands exerting a strong ligand field. The type of behaviour shown by chel* has been considered. The dissociated radical may: (i) Abstract a hydrogen atom to give the protonated ligand, (ii) dimerise, (iii) undergo coupling or degradation. A detailed investigation of the reactions of Fe(l-nqo)3 and Fe(2-nqo)3 with Ph3P (including kinetic studies) showed that these complexes undergo internal redox reactions to give iron(II) complexes and products arising from the deoxygenation of the nqo* radical. Mechanisms for these resctions have been proposed. The behaviour of quinoneoximic complexes of iron towards the Lewis base CO has been examined both directly and indirectly by studying the behaviour of nqoH towards Fe(CO)5 or Fe(CO)5/PhNH2. Fe(CO)5 and 1-nqoH or 2-nqoH afforded complexes of the type Fe(nqo)2, without formation of CO adducts or deoxygenation products. In the presence of PhNH2 complexes of type Fe(nqo)2 and Fe(nqo-A)2 resulted, where nqo-A is a species arising from the coupling of the nqo ligand with PhNH2. Both systems also afforded various organic products. On the basis of Mossbauer and other techniques oligomeric structures have been suggested for the complexes Fe(nqo)2 and Fe(nqo-A)2. Whereas CO did not react with Fe(nqo)2 or Fe(nqo)2.2py, it reacted with Fe(nqo)3, possibly via an internal redox process. For Fe(2-nqo)3 products arising from a deoxygenated ligand and a complex tentatively formulated as the nitrene species, Fe(2-nq)2, were isolated. The reactivity of the Fe(nqo), complexes towards CO has been successfully utilised in the selective filtration of tobacco smoke. Both Fe(1-nqo)3, and Fe(2-nqo)3 were shown to be capable of significantly reducing the level of CO in tobacco smoke under smoking conditions when supported on suitable filters. Reduction of the levels of other Lewis bases in tobacco smoke, e.g. nicotine and furfural, was observed. The complexes Fe(nqo)2, Fe(nqo)2.2py and Fe(nqo)3 reacted readily with NO to give complicated mixtures, but their effectiveness in removing NO from tobacco smoke has not been unambiguously established.

Sepsis, commonly referred to as blood poisoning, is a serious medical condition characterized by a whole-body inflammatory state caused by microbial infection. Rapid treatment is crucial, however, traditional culture-based diagnostics usually takes 2-5 days.  The overall aim of the thesis is to develop microfluidic based sample preparation strategies, capable of isolating bacteria from whole blood for rapid sepsis diagnostics.  Although emerging technologies, such as microfluidics and “lab-on-a-chip” (LOC) devices have the potential to spur the development of protocols and affordable instruments, most often sample preparation is performed manually with procedures that involve handling steps prone to introducing artifacts, require skilled technicians and well-equipped, expensive laboratories.  Here, we propose the development of methods for fast and efficient sample preparation that can isolate bacteria from whole blood by using microfluidic techniques with potential to be incorporated in LOC systems. We have developed two means for high throughput bacteria isolation: size based sorting and selective lysis of blood cells. To process the large blood samples needed in sepsis diagnostics, we introduce novel manufacturing techniques that enable scalable parallelization for increased throughput in miniaturized devices. The novel manufacturing technique uses a flexible transfer carrier sheet, water-dissolvable release material, poly(vinyl alcohol), and a controlled polymerization inhibitor to enable highly complex polydimethylsiloxane (PDMS) structures containing thin membranes and 3D fluidic networks. The size based sorting utilizes inertial microfluidics, a novel particles focusing method that operates at extremely high flow rates. Inertial focusing in flow through a single inlet and two outlet, scalable parallel channel devices, was demonstrated with filtration efficiency of >95% and a flowrate of 3.2 mL/min. Finally, we have developed a novel microfluidic based sample preparation strategy to continuously isolate bacteria from whole blood for downstream analysis. The method takes advantage of the fact that bacteria cells have a rigid cell wall protecting the cell, while blood cells are much more susceptible to chemical lysis. Whole blood is continuously mixed with saponin for primary lysis, followed by osmotic shock in water. We obtained complete lysis of all blood cells, while more than 80% of the bacteria were readily recovered for downstream processing. Altogether, we have provided new bacteria isolation methods, and improved the manufacturing techniques and microfluidic components that, combined offer the potential for affordable and effective sample preparation for subsequent pathogen identification, all in an automated LOC format.
QC 20120611

This thesis deals with the reduction of oxides of nitrogen (NOx) which are part of the exhaust gas combustion devices. The focus is on reduction of NOx by selective catalytic reduction (SCR) and catalyst filtration. The first part of this work deals with the formation of NOx, their hazards and related legislation. The following is an overview of the available technologies to reduce NOx in the flue gas and comparison of this methods. The following section describes the experimental catalytic filtration unit INTEQ II, where the first real experiment selective catalytic reduction of NOx with ammonia was realized. We have verified the operability of the experimental units and achieve up to 80% efficiency SCR. The final section describes the progress of the experiment and its results. It is recommended a few minor adjustments to improve stabile operation of unit INTEQ II.

Gegenstand dieser Arbeit ist die Herstellung nicht hierarchischer und hierarchischer, poröser Polymermembranen mittels eines Templatverfahrens. Bei der Herstellung der hierarchischen Membranen wird eine Stützschicht mit mikrometergroßen Mulden und eine aktive Membranschicht mit submikrometergroßen Poren in einem Arbeitsschritt und aus einem Material erzeugt. Als Template für die Poren der nicht hierarchischen Membranen bzw. Mulden der hierarchischen Membran in der Stützschicht dienen Flüssigkeitstropfen. Diese werden auf Substraten mit Bereichen unterschiedlicher Benetzbarkeit erzeugt. Die Substrate werden anschließend mit einer Polymerlösung überschichtet, welche im Falle der hierarchischen Membranen sphärische, monodisperse Siliziumdioxidpartikel enthält. Die Siliziumdioxidpartikel ordnen sich bevorzugt in der Grenzfläche zwischen den Templattropfen und der Polymerlösung an. Nach Verdunsten des Lösungsmittels, Entfernen des Substrats und ggf. der Siliziumdioxidpartikel werden poröse Polymermembranen erhalten. Die nicht hierarchischen weisen Poren in der Größe der Templattropfen aus. Die hierarchischen Membranen zeigen dagegen eine Stützstruktur mit mikrometergroßen Mulden, entstanden durch die Templattropfen und eine Schicht auf der Oberseite der Membran mit submikrometergroßen Poren, die durch die Siliziumdioxidpartikel gebildet wurden. Außerdem wird gezeigt, wie das dargelegte Verfahren auf die Herstellung von Membranen aus dem Monomer VISIOMER HEMA-TMDI übertragen werden konnte

Cette thèse porte sur l'intensification de l'extraction de polyphénols à partir de produits à base de pomme (chair, peau et marc) par ultrasons (US) et sur la purification d'extraits de peau de pomme par adsorption/désorption et technologie membranaire. L'extraction sélective des polyphénols issus des produits de la pomme a été analysée. Les données obtenues ont démontré la possibilité d’une régulation fine de l’extraction sélective de la matière soluble, de la catéchine et des composés polyphénoliques totaux en utilisant différentes températures, protocoles UAE, mélanges éthanol/aqueux. La sélectivité de l'extraction de la catéchine dépendait également du type de tissu (chair, peau ou marc) et de la variété de pomme (verte ou rouge). Le phénomène de cavitation généré par les ultrasons pourrait augmenter l'extraction de composants précieux des pelures de fruits en endommageant les membranes cellulaires des échantillons et en accélérant ainsi le transfert de chaleur et de masse. D’autre part, les solvants eau-gaz pourraient améliorer l'efficacité d'extraction des polyphénols des peaux de pomme en renforçant le phénomène de cavitation généré par les ultrasons. L'efficacité de la purification de polyphénols d'extraits de pelure de pomme par adsorption/désorption assisté par ultrasons (adsorbant polyaromatique Amberlite XAD-16) et par électrofiltration sur membrane a été mise en évidence. Les données obtenues ont démontré que la sonication facilitait significativement la cinétique d’adsorption, la capacité d’adsorption accrue et augmentation de l’énergie d’activation de l’adsorption des polyphénols. En outre, le taux de désorption a été positivement affecté par la sonication au cours de l'étape d'adsorption. Par ailleurs, les résultats ont montré que l’électrofiltration sur membrane permettait de purifier les polyphénols dans l’espace anodique (+) et d’obtenir un volume plus important de filtrats
This thesis focuses on the intensification of polyphenols extraction from apple products (flesh, peel, and pomace) by ultrasound (US) and the purification of apple peel extracts by adsorption/desorption and membrane technology. The selective extraction of phenolic contents from apple products has been analyzed. The obtained data evidenced the possibility of fine regulation of selective extraction of soluble matter, catechin and total polyphenolic compounds using different temperatures, ultrasound-assisted extraction (UAE) protocols, ethanol/aqueous mixtures. The selectivity of catechin extraction was also depended on the type of the tissue (flesh, peel or pomace) and apple variety (green or red). The cavitation phenomenon generated by ultrasound could increase extraction of valuable components from fruit peels by damaging cell membranes of samples and accelerating heat and mass transfer by disrupted cell walls of samples. Meanwhile, the gas water solvents could enhance the extraction efficiency of polyphenols and antioxidant activity from apple peels by enhancing cavitation phenomenon generated by ultrasound. The efficiency of polyphenols purification from apple peel extracts with adsorption/desorption process by ultrasound treatment with the polyaromatic amberlite adsorbent XAD-16 and with membrane electro-filtration were studied. The obtained data demonstrated that the sonication significantly facilitated adsorption kinetics and increased activation energy of polyphenols adsorption. In addition, the desorption ratio was positively affected by the sonication during the adsorption step. On the other hand, the results demonstrated that the membrane electro-filtration allowed the purification of polyphenols in the anode (+) space and obtaining larger volume of filtrates

Analysis of the regional energy supply, shows that suitable alternative may be a combination of primary energy sources with the municipal solid waste to energy plant. Starting from the fact that the regional thermal energy needs are characterized by smaller power demand, but relatively significant seasonal fluctuations in heat supply. These factors limit the processing performance of the considered waste to energy plant that could be included in the system of regional energy supply. The aim of the thesis was to propose adequate treatment capacity for regional waste to energy plant and explore alternative solutions in off-gas cleaning for exhaust gases generated during incineration of MSW. The balance sheets of two alternative solutions off gas cleaning are part of the thesis, both in terms of material and energy consumption. Presented evaluation of economic demands alternative arrangement of off gas cleaning includes operating costs and the impact on earnings from energy production.

Структура й обсяг дипломної роботи Магістерська дисертація складається зі вступу, шести розділів, висновку, переліку посилань з 30 найменувань, 2 додатків і містить 23 рисунки, 22 таблиці. Повний обсяг магістерської дисертації складає 77 сторінок, з яких перелік посилань займає 2 сторінки. Актуальність теми. Цифрова фільтрація – це те, без чого сьогодні не обходиться ніхто. Такі речі як мобільні телефони, медичні пристрої, розумні транспортні засоби, радарні станції, телекомунікації можуть робити різноманітні речі, такі як програвання аудіо і відео, обробка фотографій, прийом і передача сигналів по комп’ютерній мережі, оцінка власного перебування в просторі – все це було б неможливим без цифрової фільтрації. Цифрові фільтри задаються такими характеристиками як порядок, частота зрізу, гарантоване затухання, нерівномірність. І щоб забезпечити головну задачу фільтру – виділення корисного сигналу, потрібно забезпечити гарантоване затухання сигналу на частотах зрізу, і максимально прибрати нерівномірність в полосі пропускання. І забезпечити це можливо знайшовши правильний набір коефіцієнтів передавальної функції цифрового фільтру. Функція що оптимізується в даному випадку –це гарантоване затухання. Але вона містить багато екстремумів. Класичним методам оптимізації важко працювати в таких умовах. Проте методи глобальної оптимізації тут допомагають. Одним з таких методів є генетичний алгоритм. Зв’язок роботи з науковими програмами, планами, темами Дисертаційна робота магістра виконувалась у КПІ ім. Ігоря Сікорського у відповідності з планом наукових досліджень кафедри АПЕПС. Мета дослідження. Метою дослідження є створення продукту, що дозволятиме проектувати цифровий фільтр з оптимальними характеристиками передавальної функції за рахунок генетичного алгоритму. Для реалізації поставленої мети були сформульовані наступні завдання дослідження, що визначили логіку дослідження та його структуру: •Аналіз літератури стосовно проектування цифрових фільтрів з оптимальними параметрами і літератури стосовно методів глобальної оптимізації багатовимірних функцій; •Адаптація і реалізація генетичного алгоритму для оптимізації коефіцієнтів передавальної функції цифрового фільтра в полосі пропускання і полосах фільтрування; •Розробити програмне забезпечення для проектування цифрових фільтрів на основі частотної вибірки з оптимізацією коефіцієнтів передавальної функції; •. Розробити сховище даних спроектованих фільтрів для збереження оптимальних коефіцієнтів передавальної функції для заданих параметрів цифрового фільтру. Об’єктом дослідження є передавальна функція цифрового фільтра з частотною вибіркою. Предмет дослідження є оптимізація коефіцієнтів передавальної функції цифрового фільтра з частотною вибіркою за допомогою генетичного алгоритму. Методи дослідження: При вирішенні задач роботи застосовувались наступні методи: • Генетичний алгоритм; • Частотна вибірка. Наукова новизна одержаних результатів. Модифікований метод генетичного алгоритму для оптимізації передавальної функції цифрового фільтру. Практичне значення одержаних результатів роботи полягає в тому що її можна використати для проектування оптимальних цифрових фільтрів з частотною вибіркою.
The structure and volume of the thesis. The master's thesis consists of an introduction, six sections, conclusion, a list of links of 30 titles, 2 appendices and contains 23 drawings, 22 tables. The full volume of the master's thesis is 77 pages, of which the list of links occupies 2 pages. Actuality of theme. Digital filtering is something that nobody can do today. Things like mobile phones, medical devices, smart vehicles, radar stations, telecommunications can do a variety of things, such as audio and video playback, photo processing, receiving and transmitting signals over a computer network, evaluating your own space would be impossible without digital filtering. The digital filters are given such characteristics as order, cutoff frequency, guaranteed damping, non-uniformity. And to provide the main task of the filter - the selection of useful signal, itis necessary to provide a guaranteed attenuation of the signal at the cutoff frequencies, and to remove as much as possible the irregularity in the bandwidth. And to ensure this is possible by finding the right set of coefficients of the transfer function of the digital filter. The optimized function in this case is a guaranteed damping. But it contains many extremes. Classical optimization methods are difficult to work under such conditions. However, global optimization techniques are helpful here. One such method is the genetic algorithm. Relationship with academic programs, plans, themes. The dissertation work of the master was carried out in KPI them. Igor Sikorsky in accordance with the plan of scientific research of the Department of APEPPS. The aim of the study. The purpose of the study is to create a product that will allow the design of a digital filter with the optimal characteristics of the transfer function due to the genetic algorithm. To achieve this goal the following objectives were formulated research following tasks the logic and structure: • Analysis of literature on design of digital filters with optimal parameters and literature on methods of global optimization of multidimensional functions; • Adaptation and implementation of a genetic algorithm to optimize the coefficients of the transfer function of a digital filter in the bandwidth and filtering bands; • Develop software for designing digital filters based on frequency sampling with optimization of transmission coefficients; • Design a data filter repository to store optimal transfer coefficients for a given digital filter parameter. Object is a transfer function of a digital filter with frequency sampling. The subject is the optimization of the coefficients of the transfer function of a digital filter with frequency sampling by means of a genetic algorithm. Methods: The following methods were used in solving the problems of work: • Genetic algorithm; • Frequency sampling. Scientific novelty of the results. A modified genetic algorithm method to optimize the transfer function of a digital filter. The practical significance of the results of job is that it can be used to design optimal frequency-sampled digital filters.

The diploma thesis is divided into four main parts. The first part deals with the issue of waste management and its energy utilization in waste incineration. Processed harmful substances produced by incineration as well as emission limits. It deals with the types of catalytic carriers, their description, production and more detailed processing of ceramic foam VUKOPOR. The second part is devoted to technologies utilizing catalytic processes and a more detailed specification of the process. In the third part there is processed the calculation methods for pressure losses for individual types of carriers. Fourth, the most extensive part describes the INTEQII experimental device, its technology and construction, as well as the principle of the practical part, measuring of the pressure losses of carriers. It includes the evaluation of pressure losses in separate categories of carriers, such as the bed, HoneyComb and VUKOPOR ceramic foam. Subsequently, a comparison of the pressure losses of all carriers is made relative to the reference size of 1 m. The impact of bonding of VUKOPOR foam samples on the size of pressure losses is discussed. At the end of this section, the suitability of calculation methods for individual carriers is evaluated, depending on the experimental pressure loss data.

The stainless steel industry is an industry which manufactures one of the most used ma-terials in the world. Even though the vast size of the industry many might not reflect werethe steel comes from when buying their IKEAcutlery etc. But in fact this industry is moreintricate and complex than one might think.During the manufacturing process, the steelgoes through several processes. One of thoseprocesses is done by treating the steel withstrong acid. This chemical process is calledpickling. The pickling process is what createsthe characteristic smooth and shiny surface ofa product made in stainless steel.This thesis is about the development of a testunit that is able to effectively test the ASRA(Acid Sludge Removal Apparatus) filter cloths.The ASRA is a filtration system developed by Scanacon in Stockholm that filtrates and puri-fies acid that is used during the pickling pro-cess of a steel manufacture process. Today, it is complicated, time consuming and dangerous totest and evaluate different filter cloths in orderto find the cloth that provides the best result,since the tests has to be conducted on the realsystems. The aim of this thesis was therefore tosolve these problems. Scanacon wanted to findan alternative solution, that would not includeinteraction with the real filtration system. Theyalso wanted a portable and safe solution. To solve the problem a iterative design pro-cess called RDCD which stands for research, design, create & delivery was developed. Theprocesses was heavily influenced by the CDIO process (Conceive, Design, Implement & Ope-rate). After the research phase was conducted it was decided that a small filter analysis productwould be the best way to solve the problem. The product was then developed one com-ponent at a time. During the project several prototypes and test was created and conductedin order to validate the design.The result is a small filtration unit speciallydesigned to simulate the ASRA system. Theproduct is able to rapidly test various filtercloths in an easy way, without putting the user in harm’s way. After the tests has been perfor-med can the user can identify which cloth that worked the best. The product is small enoughto be possible to be carried in a hard case bag,which in turn affords portability.
Stålindustrin är en industri som tillverkar ettav de mest använda materialen i världen. Trotsindustrins enorma storlek är det kanske intemånga som reflekterar varifrån stålet kommerifrån när man köper exempelvis IKEA bestick.Men faktum är att den här industrin är mycketmer invecklad och komplex än vad man kan tro. Under tillverkningsprocessen går stålet ige-nom flera processer. En av de här processerna genomförs genom att behandla stålet med starksyra. Den kemiska processen kallas för betningoch är det som ger en produkt tillverkad i stålden karaktäristiska lena och glänsande ytan. Den här examensrapporten handlar om ut-vecklandet av en test enhet som effektivt kan testa filter dukarna till ASRA (Acid SludgeRemoval Apparatus) systemet. ASRA systemetär ett filtreringssystem utvecklat av Scanaconi Stockholm som filtrerar och renar syran som används under betningsprocessen vid stål-tillverkning. Idag är det komplicerat, tidskrä-vande och farligt att testa och utvärdera olika filterdukar för att ta reda på vilken duk somger bäst resultat, eftersom att testerna måstegenomföras på de riktiga systemen. Målet fördet här examensarbetet var därför att lösa dehär problemen. Scanacon ville ha en alternativlösning som inte kräver interaktion med deriktiga systemen. De ville också ha en portabeloch säker lösning. För att lösa problemet utvecklades en itera-tiv designprocess kallad RDCD som står för research, design, create & delivery. Processen var tungt influerat av CDIO (Conceive, De-sign, Implement & Operate) processen. Efter att researchfasen var genomförd bestämdesdet att en liten filteranalysatorprodukt var detbästa sättet att lösa problemet på. Produktenutvecklades sedan en komponent i taget. Underprojektets gång har flera prototyper byggts och flera tester genomförts för att validera designen. Resultatet är en liten filtreringsenhet som är specialdesignad för att simulera ASRA syste-met. Produkten kan snabbt testa oliak filterdu-kar på ett enkelt sätt, utan utsätta användaren för fara. Efter att testerna genomförts kananvändaren identifiera vilken duk som funkatbäst. Produkten är tillräckligt liten för att fåplats i en hårdplast väska, vilket ger produktenden efterfrågade portabiliteten.

碩士
中原大學
化學工程研究所
103
The membrane permeate flux will decrease with the increasing operating time mainly because of the resistance generated by fouling on the membrane surface and pore. In order to identify the change of membrane fouling, several data-driven modeling methods, such as partial least squares (PLS) and artificial neural networks (ANNs), have been used to identify the fouling change. However, the PLS model is linear, so it is insufficient to capture the nonlinear relationship in the fouling mechanism. Although ANN is able to model the nonlinear relationship, it is still difficult to determine the network topology for a complex modeling task. Additionally, both PLS and ANN models are deterministic, which means that the probabilistic information for its prediction is not provided. In this work, a novel probabilistic method named Gaussian process regression (GPR) is proposed to model the complex nonlinear fouling mechanism. The GPR model can simultaneously provide the prediction uncertainty, e.g., the prediction variance. As a result, the model can be updated in a simple and efficient manner without adding unnecessary data samples when the fouling changes. The superiority of the proposed method is demonstrated through several experiments. The membrane fouling will be influenced by operation flux, operation time and other factors. The membrane fouling should be cleaned up at the appropriate time. However, membrane filtration is a decay procedure because feed materials may adhere to the pores of the membrane and the membrane would be not completely cleaned up. The membrane operation leads to a significant loss in separation performance and the high energy increases the operation cost if operation flux or time is not proper. The traditional method designs the operation condition only based on the physical models. The models may not be adequately built in advance. In this work, the distributed prediction of the GPR model is utilized to develop an active design based on the combination of the physical and the GPR model, especially for incomplete models. Unlike most of the past research, the design is based on the expected improvement strategy which is able to exploit information from the current data as well as to explore uncharted regions. The cost of the operations would be kept as low as possible while the favorable design performance can be guaranteed. The superiority of the hybrid models and the active learning design is demonstrated using simulation and experiments. The results show the proposed methods yield better prediction performance and lower operation costs and they are more efficient than the other conventional methods.

The lack of safe drinking water worldwide has drawn the attention of decision makers to riverbank filtration (RBF) for its many advantages in purifying surface water. This study provides an overview of the hydrogeologic, fluvial, and environmental influences on the performance of RBF systems and aims to develop a model for RBF site selection. Using multi-attribute utility theory (MAUT), this study structured the RBF siting problem and assessed a multiplicative utility function for the decision maker. In a case study, geostatistical methods were used to acquire the necessary data and geographic information systems (GIS) were used to screen sites suitable for RBF implementation. Those suitable sites were then evaluated and ranked using the multi-attribute utility model. The result showed that sites can be identified as most preferred among the selected suitable sites based on their expected utility values. This study definitively answers the question regarding the capability of MAUT in RBF site selection. Further studies are needed to verify the influences of the attributes on the performance of RBF systems.:Abstract iii Zusammenfassung iv Acknowledgments v Table of Contents vi List of Tables viii List of Figures x Definition of terms xiii 1. Abbreviations xiii 2. Symbols xiii Part I Introduction 1 1. Introduction 2 2. Statement of purpose 2 3. Research questions 3 4. Overview of methodology 3 5. Organization of the dissertation 3 Part II Fundamentals and Literature Review 5 1. The definition of bank filtration 6 2. The Significance of RBF 7 2.1 RBF in drinking water supply 7 2.2 Benefits of RBF for China 14 3. RBF Site Selection 19 3.1 RBF site selection model 20 3.2 Definition of successful RBF sites 24 4. Factors Affecting RBF Site Selection 26 4.1 River hydrology/hydraulics 27 4.2 Geology 28 4.3 Land cover 36 4.4 Well field location 36 4.5 Water quality 37 4.6 Aquifer properties 38 4.7 Distance to river 41 4.8 Riverbed characteristics 43 5. Effect of Clogging on Yield 46 6. Summary 51 Part III Developing a Multi-attribute Utility Model for RBF Site Selection 53 1. Introduction 54 2. Objectives and Attributes 54 3. Assessment of the Utility Function 57 3.1 Investigation of the qualitative preference structure 58 3.2 Assessment of component utility function 62 3.3 Assessment of the scaling constants 63 4. Results 67 5. Discussion 69 6. Summary 74 Part IV Case Study 75 1. Introduction 76 2. Materials and Methods 78 2.1 GIS data collection 78 2.1.1 Geologic data 79 2.1.2 Land cover data 79 2.1.3 Groundwater quality data 80 2.1.4 Aquifer properties data 80 2.1.5 Surface water area data 80 2.1.6 Surface water quality data 81 2.1.7 Streambed material data 81 2.2 Kriging the saturated thickness 91 2.3 Aggregation of all constraint maps 103 3. Results 105 3.1 Kriging 105 3.2 Suitable sites 105 4. Discussion 109 4.1 A discussion of the kriging results 109 4.2 A discussion of the multi-attribute utility model results 117 5. Summary 122 Part V Conclusions and Recommendations 123 1. Conclusion and Recommendation 124 Appendix 1 Environmental quality standards for surface water (GB 3838-2002) 125 Appendix 2 Quality standard for groundwater (GB14848-93) 127 Appendix 3 Explanation to Germany’s RBF site location data 130 Appendix 4 Layer information of drillings 133 Appendix 5 Streambed materials used by Schälchli (1993) 141 Appendix 6 Interview and questionnaires 143 Appendix 7 Surface water area of Jilin City 150 Bibliography 152