Dissertations / Theses: 'Kinetic researches'

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Eliasson, Bengt. "Numerical simulation of kinetic effects in ionospheric plasma." Licentiate thesis, Uppsala : Dept. of Information Technology, Univ, 2001. http://www.it.uu.se/research/reports/lic/2001-004/2001-004-nc.pdf.

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Arant, Charles. "Kinetic Problem Solving." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6997.

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Government leaders stand to benefit from improved program management capabilities within their organizations. Often, they are faced with crisis situations that require a rapid-fire, precise, effective problem solving process. Some of these programs are more severe or complex than others. With time and certainty of the solution as constraints, efficient program management supporting the Defense Acquisition Life Cycle remains an enigma for organizations at best and a hazard at worst. Program management dealing with crisis problem solving, which is characterized by critical events and high cost, is a real-time process where requirements are identified and resolved to achieve a desired goal, with the path to the goal blocked by known or unknown obstacles. Program management that deals with crisis problem solving situations are plagued by several issues. The crisis situation is likely one not previously encountered; therefore, solutions from past experiences cannot be drawn upon to solve the problem (Heichal, 1992). An individual not experienced or trained often feels the situation is too complex, information is incomplete, time is short, and failure consequences are extreme (Hockey, 1986). Managers who face these dilemmas must have responsive, failure-proof processes in place. This dissertation explores program management as it deals with problem solving processes in time-critical contexts, including task consolidation and resource selection, with the critical objective of improving crisis event management. The intent is to focus on processes that can be improved in crisis problem solving, specifically time needed to execute current problem solving processes, and introduce a kinetic problem solving approach to increase the momentum of implementing the solutions during crisis situations. This flexibility is facilitated by the researcher’s genuine desire to improve the organizational situation (rather than merely study it) and a client’s willingness to share the details of how they will use the technology and lessons learned.

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Воронова, Анастасія Сергіївна. "Синтез та каталітичні властивості мезопоруватих нікель-кобальтових шпінелей та їх композитів." Master's thesis, КПІ ім. Ігоря Сікорського, 2019. https://ela.kpi.ua/handle/123456789/29007.

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У контексті сучасного пошуку та досліджень альтернативних джерел енергії електрохімічні системи зберігання та перетворення енергії займають значну нішу. Відкритим для дослідження питанням, пов'язаним з електрохімічними джерелами енергії, є розробка та пошук ефективних, екологічно чистих та економічно ефективних каталізаторів для паливних елементів. Перспективним напрямком у цій сфері є дослідження змішаних оксидних каталізаторів, зокрема каталізаторів зі структурою шпінелі. Сполукою, що привертає значну увагу у цій області є Ni-, Co-шпінель складу NiCo2O4 та її різноманітні композитні матеріали із поруватими носіями з розвиненою поверхнею. Об’єкт дослідження – нікель-кобальтові шпінелі та їх композити з багатошаровими вуглецевими нанотрубками та активованим вугіллям. Предмет дослідження – синтез, фізико-хімічні властивості нікель-кобальтових шпінелей та їх композитів з багатошаровими вуглецевими нанотрубками та активованим вугіллям. Метод дослідження – експериментальний. У ході роботи досліджено структурні характеристики, морфологію поверхні та фазовий склад зразків за допомогою методів низькотемпературної адсорбції-десорбції азоту, скануючої електронної мікроскопії, інфрачервоної спектроскопії та рентгеноструктурного аналізу. Каталітичну активність синтезованих зразків досліджено в модельних рідинно-фазних гетерогенно-каталітичних реакціях гідролізу борогідриду натрію та розкладання пероксиду водню. Іоннообмінні характеристики поверхні синтезованих зразків досліджено методом pH-потенціометричного титрування. У якості методу синтезу запропоновано простий на технологічний метод співосадження. Синтезовано чисті нікель-кобальтові шпінелі, а також та їх композити з багатошаровими вуглецевими нанотрубками та активованим вугіллям. Як показали отримані дані, синтезовані зразки володіють усіма властивостями ефективного каталізатора, який може бути використаний в електрохімічних джерелах енергії. Синтезовані композитні матеріали можна застосовувати у різноманітних електрохімічних пристроях зберігання та перетворення енергії, в тому числі у борогідридних паливних комірках прямої дії.
In the context of modern search and investigation of alternative energy sources, electrochemical energy storage and convertion systems occupy a significant niche. Open for research issue, related to electrochemical energy sources, is the development and search of efficient, environmentally friendly and cost-effective catalysts for fuel cells. A promising direction in this area is the study of mixed oxide catalysts, namely catalysts with a spinel structure. The compound that attracts considerable attention in this area is the Ni-, Co-spinel of the NiCo2O4 composition and its various composite materials with the developed surface carrier. The object of the study is Ni-, Co-spinels and their composites with multiwalled carbon nanotubes and activated carbon. The subject of the study is the synthesis, physical and chemical properties of Ni-, Co-spinels and their composites with multiwalled carbon nanotubes and activated carbon. The research method is experimental. During the work, the structural characteristics and surface morphology of the samples were investigated using methods of low-temperature N2 adsorption-desorption, scanning electron microscopy and X-ray diffration. The catalytic activity of the synthesized samples was investigated in the course of a model liquid-phase heterogeneous-catalytic reaction of sodium borohydride hydrolysis and decomposition of hydrogen peroxide. The ion exchange characteristics of the synthesized samples surface were investigated during pH-tertiometric titration. A simple and technological method of co-precipitation was proposed as a synthesis method. Pure nickel cobaltite and its composites with active carbon and carbon nanotubes were synthesized. As the obtained data showed, the synthesized samples possess all the properties of an effective catalyst that can be used in electrochemical energy sources. The synthesized composite materials can be used in a variety of electrochemical storage and energy conversion devices, including direct borohydride fuel cells.

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Brown, Darryl Edward. "Kinetic models for the Pt/CeO₂ catalysed water-gas shift reaction." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/27914.

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As the global population grows, so does the world's demand for energy. Consequently, there exists an increased interest in the development of fuel cells for power generation due to their low greenhouse gas emissions. For fuel cells to be a successful power source, a reliable hydrogen source is required. Ultimately, the goal is for hydrogen to be supplied from renewable energy technology however, this type of technology is currently not mature enough to meet the continuous demand of the world's energy systems. Producing hydrogen from fossil fuels can be seen as a temporary solution while further advances are made in developing renewable hydrogen infrastructure. A fuel processing train, therefore, remains an important alternative to producing hydrogen. A fuel processing train converts fossil fuels into hydrogen for use in fuel cells and eliminates the need for hydrogen storage as hydrogen is produced on demand. Currently, the water-gas shift (WGS) reactor is one of the largest components in a fuel processing train and thus opportunity exists to reduce the size of this reactor. To design future WGS catalysts and an optimised fuel processor, the reaction kinetics taking place must be understood and quantified. In this study, kinetic measurements were conducted at 2 bar(a) and across a temperature range of 270 - 300 °C using 16 parallel fixed bed reactors (high throughput experimentation) over a 0.5 wt% Pt/CeO₂ catalyst. The feed composition was varied over the ranges 2 - 12 mol% CO, 20 - 45 mol% H₂O, 4 - 15 mol% CO₂ and 25 - 55 mol% H₂. An online micro gas chromatograph (μGC) was used to analyse the dry gas composition. Fitting of experimental data to various kinetic models was accomplished with the gPROMS software package. An initial evaluation of several Langmuir-Hinshelwood (LH) type mechanisms to two data sets obtained from literature was undertaken to evaluate the strengths and weaknesses of different kinetic expressions. The results of the initial evaluation indicate that a dual-site mechanism with an intermediate species results in the best fit for reducible supports, while a single site mechanism offers a better fit for non-reducible supports. For both kinetic models, the formation of the intermediate species is most likely to be the rate determining step. A power-rate law empirical rate expression and a LH type rate expression were both found to predict the WGS outlet composition well within 10 % error at 2bar(a). The apparent activation energy of the reaction was determined to be 110 kJ/mol. This value was confirmed to be constant, throughout the range of conditions evaluated, by means of a classical Arrhenius analysis. Simulations of increasing total system pressure, using both the empirical and "best fitting" LH model, indicate a significant pressure effect for the LH type equation, whereas the power-rate law empirical equation predicts a small, negative effect on the reaction rate with increaseing pressure. Consequently, further experiments were conducted to determine the true effect of pressure. It was found that increasing system pressure increased the WGS reaction rate, which has also been reported by Twigg (1989:288). Only the LH type rate expression was able to predict this. It is therefore recommended that either the power-rate law empirical rate expression or the LH type rate expression be used to predict the WGS outlet composition when operating below 2 bar(a). Furthermore, when predicting reaction rates outside of the window in which the rate equations were derived, it is recommended that the LH model be used as it is expected to give a better prediction as it is based on fundamental steps.

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Cleverly, Douglas Robert. "Bile salt-stimulated human milk lipase characterisation and kinetic studies." Thesis, University of Auckland, 1992. http://hdl.handle.net/2292/2329.

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Chapter One begins with an introduction to enzymology and leads into a discussion on BSSL beginning with the physical properties and the source of the enzyme. The literature concerning the kinetic properties of BSSL is reviewed, followed by a discussion on how the structure of enzymes influences their catalytic activity and specificity. The use of X-ray crystallographic techniques is addressed as a means of elucidating the three dimensional structure of enzymes. The chemicals, apparatus and standard methodologies used in this present investigation are described in Chapter Two. The means by which kinetic data measured for an enzyme-substrate system are analysed and compared are also discussed. Chapter Three describes the purification of bile salt-stimulated human milk lipase (BSSL) from whole human milk. A detailed study of the activity of the purified protein has been conducted against both lipid and ester substrates in order to monitor the progress of the purification. A further determination of the physical properties of the protein has also been conducted. Results from these studies have identified the protein as BSSL. In Chapter Four the methods used for determining the partial amino acid sequence of the enzyme are described. This study has revealed interesting homologies with enzymes from other species. The sequence of that part of the enzyme which includes the active site has been determined and has been found to be identical to the consensus sequence found in the active site of pancreatic lipase, serine proteases and cholinesterases. It may therefore be postulated that the similarity observed for some of the kinetic behaviour of enzymes arises from homology in their amino acid sequences and, in particular, those portions of the protein comprising the active site. The use of kinetic isotope effects, to gain insight as to the mechanism of BSSL catalysed hydrolysis of lipid substrates, is the subject of Chapter Five. A mechanism has been proposed which explains the observed effects and takes into account information from the literature. The mechanism also incorporates findings made from the amino acid sequence study and the literature reports on the residues involved in catalysis. Chapter Six begins within a literature survey of detergent less microemulsions and continues with an account of the kinetic properties of BSSL in this new and novel medium in which enzymic reactions involving substrates of low water solubility may be conducted. The advantage of this medium is that it allows one to monitor the reaction by spectrophotometric means. In more traditional methods of assay of lipid substrates this is not normally possible. This advantage has also been exploited in the study of the kinetics of BSSL against triolein in reversed micelles, which is the subject of Chapter Seven. A detailed description is given of an FT-IR technique which allows one to monitor the course of reaction of biologically important substrates.

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Shaw, Rebecca Custis Riehl. "Combining combustion simulations with complex chemical kinetics." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648248.

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White, James. "A kinetic study of the behaviour of plasminogen activating enzymes towards synthetic substrates." Thesis, Queen's University Belfast, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235843.

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Mbiya, Wilbes. "Kinetics and Mechanism of S-Nitrosation and Oxidation of Cysteamine by Peroxynitrite." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1413.

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Cysteamine (CA), which is an aminothiol drug medically known as Cystagon® was studied in this thesis. Cysteamine was reacted with a binary toxin called peroxynitrite (PN) which is assembled spontaneously whenever nitric oxide and superoxide are produced together and the decomposition of peroxyinitrite was monitored. PN was able to nitrosate CA in highly acidic medium and excess CA to form S-nitrosocysteamine (CANO) in a 1:1 with the formation of one mole of CANO from one mole of ONOOH. In excess oxidant (PN) the following 1:2 stoichiometric ratio was obtained; ONOO- + 2CA → CA-CA + NO2- + H2O . In alkali medium the oxidation of CA went through a series of stages from sulfenic acid, sulfinic acid and then sulfonic acid which was followed by the cleavage of the C-S bond to form a reducing sulfur leaving group, which is easily oxidized to sulfate. The nitrosation reaction was first order in peroxynitrite, thus implicating it as a nitrosating agent in highly acidic pH conditions. Acid catalyzes nitrosation reaction, whitst nitrate catalyzed and increased the amount of CANO product, This means that the nitrosonium cation, NO+ which is produced from the protonation of nitrous acid(in situ) as also contributing to the nitrosation of CA species in highly acidic environments. The acid catalysis at constant peroxynitrite concentrations suggests that the protonated peroxynitrous acid nitrosates at a much higher rate than the peroxynitrite and peroxynitrous acid. Bimolecular rate constants for the nitrosation of CA, was deduced to be 10.23 M-1 s-1. A linear correlation was obtained between the initial rate constants and the pH. The oxidation of CA was modeled by a simple reaction scheme containing 12 reactions.

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Brown, Michael Duane. "An investigation of fine coal grinding kinetics." Thesis, Virginia Tech, 1986. http://hdl.handle.net/10919/45752.

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In recent years, a great deal of interest has been shown in developing methods for preparing super—clean coal containing less than 2% ash and 0.5% sulfur. New techniques for recovering fine coal, such as micro—bubble flotation, can achieve the desired result provided mineral matter is sufficiently liberated. To achieve sufficient liberation, however, it is often necessary to grind to a mean particle size finer than 10 microns. Since conventional ball mills are highly inefficient in this fine size range, the stirred ball mill has been proposed as a more suitable means for ultrafine grinding.
Master of Science

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Poisl, W. Howard. "Sintering kinetics of the superconducting YBa₂Cu₃O compound." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/29752.

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The effect of oxygen partial pressure and temperature on the solid state sintering kinetics of the superconducting ceramic YBa₂Cu₃O₇₋₈ has been investigated. The isothermal contraction behavior of YBa₂Cu₃O₇₋₈ in the temperature range 930 - 960°C with oxygen partial pressures varying from 0.001 to 1.0 atmospheres was studied. The change in the unit cell lattice parameters of YBa₂Cu₃O₇₋₈ over this oxygen partial pressure range was also determined in order to evaluate its effect on the sintering behavior. The sintering kinetics of YBa₂Cu₃O₇₋₈ were investigated through the variation of the isothermal steady state contraction rate with respect to oxygen partial pressure at different temperatures. Isothermal contraction rates between 930 and 955°C reached a maximum at some critical oxygen partial pressure, PO₂CRIT, with decreasing contraction rates both above and below this oxygen partial pressure. This behavior was not observed for YBa₂Cu₃O₇₋₈ sintered at 960°C. SEM micrographs of the fracture surface of these samples suggest that a liquid phase was formed at this temperature. The unit cell volume and a-lattice parameter of YBa₂Cu₃O₇₋₈ decreased with decreasing oxygen partial pressure, while the c-lattice parameter increased. The activation energy for sintering at oxygen partial pressures above PO₂CRIT has been estimated to be approximately 191 kJ/mole, which is similar to oxygen ion diffusion in this compound, indicating that for oxygen partial pressures above PO₂CRIT, oxygen diffusion is the rate controlling mechanism for mass transport. The activation energy for sintering below PO₂CRIT was found to be ∽130 kJ/mole, which could also be due to oxygen ion diffusion. Several possible factors have been considered for the sintering behavior of YBa₂Cu₃O₇₋₈ for oxygen partial pressures below PO₂CRIT. These are formation of copper vacancies, positive hole creation, and lattice strain effect. However, although the oxygen partial pressure dependence on the sintering rate can be correlated with either the formation of Cu²⁺ vacancies in the lattice or hole formation, neither of these mechanisms are considered to be probable. Mathematically, the contraction rate was found to depend exponentially on the lattice strain (Δɛlat), ie. έ∞еΔɛlat. The significance of this relationship is not clearly understood. Intuitively, it appears that as the vacancies are created due to the removal of oxygen ions from the lattice, the lattice is not contracting to the extent needed to accommodate the vacancies. This elastic strain hinders the migration of the oxygen vacancies through the lattice, thus affecting the sintering rate of the YBa₂Cu₃Ox compound below PO₂CRIT.
Applied Science, Faculty of
Materials Engineering, Department of
Graduate

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Chermak, John Alan. "The kinetics and thermodynamics of clay mineral reactions." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54505.

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The diagenesis of rocks during burial occurs in response to changing temperature, pressure, and solution composition. Due to their geologic abundance, high surface area, and reactivity clay minerals are important participants in the diagenesis of clastic rocks. The kinetic and thermodynamic stability of clays is in general poorly understood. This dissertation research measured the rate of transformation of kaolinite to muscovite/illite and developed a method to estimate clay mineral thermodynamic stability. Clastic rock diagenesis is controlled by the rates of silicate mineral growth and transformation. Marine mudstones commonly contain large proportions of kaolinite which reacts during diagenesis to form muscovite/illite and/or chlorite. Batch reactor experiments were used to measure the reaction rate of 1.5 kaolinite + K⁺ = muscovite + H⁺ + 1.5 H₂O using the initial rate method and a fitted form of the integrated rate equation. Experiments were performed at temperatures ranging from 250° to 307°C with solutions of 0.5 - 2.0 m KCl. These results can then be extrapolated to diagenetic temperatures using the Arrhenius equation. ln addition, a technique was developed to estimate the ΔG_f0 and ∆H_f0 of silicate minerals. Silicate minerals have been shown to act as a combination of basic polyhedral units (Hazen 1985 and 1988). This work showed that their thermodynamic properties could be modeled as the sum of polyhedral contributions. A multiple linear regression model was used to find the contribution of the oxide and hydroxide components (gᵢ and hᵢ) to the ΔG_f0 and ∆H_f0 of a selected group of aluminosilicate minerals at 298 K. The ΔG_f0 and ∆H_f0 of other silicate minerals can be estimated from a weighted sum of the contribution of each oxide and hydroxide component (gᵢ and hᵢ). These results can be also used to estimate the ΔG_f0 of silicate minerals at higher temperatures (up to =600 K) by using the equation, gᵢ(T)= hᵢ(298) - T((hᵢ(298)-gᵢ(298))/298)
Ph. D.

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Gélinas, Marc Paul. "Kinematic comparison of same and opposite-field hitting in baseball." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61873.

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Blumoff, Sonja. "Oxygen Uptake Kinetics in Severe Intensity Exercise." Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2539/.

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The purpose of this study was to describe mathematically the oxygen uptake kinetics during cycle ergometry, and to examine the effect of intensity on the kinetic responses within the severe domain. Sixteen volunteers performed a series of exercise tests at a range of intensities selected to elicit fatigue in ~3 to 10 min. A simple mono-exponential model effectively described the response across all intensities. There was a positive correlation between the response time and the time to fatigue, demonstrating that the maximal oxygen uptake was achieved faster at higher intensities within the severe domain. Models incorporating two components effectively described the responses only in tests lasting 8 min or more. It was concluded that there is a second, slow component in the oxygen uptake response only at the lower intensities within the severe domain.

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Liu, Yuanlong. "The statistical validity of using ratio variables in human kinetics research." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0019/NQ46373.pdf.

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Angelis, Georgios. "Novel spatiotemporal image reconstruction for high resolution PET imaging in neuroscience." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/novel-spatiotemporal-image-reconstruction-for-high-resolution-pet-imaging-in-neuroscience(8a251bc6-3ba6-48e2-8a7e-7fb0c0726ba0).html.

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Positron emission tomography (PET) is a widely used molecular imaging modality,which offers quantitative information about many biochemical processes in vivo. In particular, the dynamic PET data provide physiologically meaningful parametricimages after the estimation of the parameters of a model that best describes thekinetic behaviour of the injected radiotracer. Spatiotemporal 4D image reconstructionalgorithms estimate these physiological parameters directly from the raw sinogramdata, where the noise distribution can be more accurately modelled and thus leading tostatistically more reliable parameter estimates. In this thesis a novel direct parametricimage reconstruction algorithm is introduced, which is based on the expectationmaximisation (EM) framework and is applicable to any spatiotemporal model. Themethod is evaluated for the spectral analysis model, which is a linear temporal modeland a two-tissue compartment model, which is a nonlinear temporal model. Inaddition, the method is evaluated for a linear spatial model and in particular the modelthat is normally used to describe the blurring components in image-based resolutionmodelling. Finally, the performance of gradient-based 3D reconstruction algorithmswas also assessed as an alternative to the well-established EM-based algorithms.

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Messenger, John. "The stoichiometry and kinetics of biological heat generation in the aerobic stage of dual digestion." Doctoral thesis, University of Cape Town, 1991. http://hdl.handle.net/11427/22165.

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Over the past 10 years the Water Research Commission (WRC) has recognized the potential benefits of the dual digestion system for South Africa where anaerobic digestion is the preferred method of sludge stabilization. Accordingly, from 1981 to 1984 under WRC sponsorship, the Johannesburg City Council (JCC) undertook a pilot plant study into the performance of the autothermal thermophilic aerobic reactor oxygenated with pure oxygen. As a consequence of the encouraging results obtained in this study (Trim and McGlashan, 1984; Trim, 1984), in 1987 the WRC and Milnerton Municipality supported a frill scale evaluation of dual digestion ( 45 ma pure oxygen oxygenated aerobic reactor and 600 ma anaerobic digestor) at Milnerton's Potsdam Wastewater Treatment Works, with scientific and academic input by the Division of Water Technology of the CSIR and the Department of Civil Engineering, of UCT. In this evaluation a number of important considerations needed to be addressed such as (1) oxygen requirements and oxygen utilization efficiency with pure oxygen and air oxygenation, (2) minimum retention time that can be achieved in the aerobic reactor and in the anaerobic digestor without comprormsmg the attainment of thermophilic temperature in the reactor and VS removal, gas production and sludge stability in the digestor, (3) temperature control of the aerobic reactor and anaerobic digestor, ( 4) efficacy of pathogen inactivation and mode of operation to prevent recontamination, (5) dewaterability of the anaerobically digested sludge, (6) operation and economic evaluation of the system. In this thesis, the results obtained pertaining to operation and performance of the Milnerton aerobic reactor are presented in detail. Also, the observed results are generalized and, based on the observed general principles, a design procedure and a simulation algorithm and computer programme for pure oxygen and air oxygenated reactors are developed, in accordance with objectives (1) to (3) above.

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Elder, Ileana. "Kinetic and structural studies on the activation of the proton transfer in catalysis by carbonic anhydrase." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0006645.

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Thesis (Ph.D.)--University of Florida, 2004.
Typescript. Title from title page of source document. Document formatted into pages; contains 116 pages. Includes Vita. Includes bibliographical references.

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Brown, Christopher A. "Aspects of the calcium carbonate-water interface." Thesis, University of Oxford, 1992. http://ora.ox.ac.uk/objects/uuid:0d9222b6-2d2a-4f3d-a0f9-61f91433dd02.

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The channel flow method has established the net dissolution kinetics of calcite single crystals at high pH (7.7-9.7) and varying bulk Ca²⁺ concentrations (0-10 mM), using wide ranges of solution flow rates (10^-3-0.3 cm³ s^-1). Literature rate equations were in poor agreement with experiment. Modelling with the following mechanism, where Ca²⁺ and CO₃^2- undergo Langmuirian adsorption: Ca²⁺_(aq) ⇄ Ca²⁺_(ads) CO^2-3 (aq) ⇄ CO^2-_{3 (ads)} Ca(sup>2+(ads) + CO^2-_{3 (ads)} ⇄ CaCO_{3 (ads)} CaCo_{3 (ads)} → CaCo_{3 (lattice)} and the consequent rate law J_net/mol cm^{-2s^-1 = k_pK_CaK_CO₃ {K_sp - [Ca²⁺]_o[CO^2-₃]_o (1 + K_Ca[Ca²⁺]_o)(1 + K_{CO₃[CO^2-₃]_o) gave excellent agreement with experiment under all conditions studied. This mechanism is shown to explain all literature streaming potential, electrophoresis and kinetic salt effect data. Dissolution of calcite under the above conditions was strongly inhibited by Mg²⁺ and fully deprotonated forms of succinic acid, 2-sulphobutanedioic acid, phthalic acid and maleic acid. Mechanisms were established; for the maleate dianion, the inhibition was due to the blocking of the dissolution sites at which CaCO₃ units are incorporated into the crystal lattice. For the other ions, inhibition arose from competitive Langmuirian adsorption either between CO₃^{2-^{and the anions, or between Ca²⁺ and Mg²⁺. A new method to quantify the inhibited dissolution of particulate CaCO₃ (=10 μm) via enhanced mass transport of solution to the rotating disc electrode, due to the rotation of the particles in the diffusion layer, has been established. Good agreement was found with that measured independently using the channel flow cell. A.c. impedance spectroscopy has been used to characterise scaled (CaCO₃) steel tubes. Results provide scope for (i) monitoring scale growth, and (ii) use in safety control devices for alerting to the scaling of pipe-work.}}}}

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Fang, Yu-Hua. "Quantification of Pharmacokinetics in Small Animals with Molecular Imaging and Compartment Modeling Analysis." Cleveland, Ohio : Case Western Reserve University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1238635584.

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Thesis (Ph.D.)--Case Western Reserve University, 2009
Department of Biomedical Engineering Abstract Title from OhioLINK abstract screen (viewed on 10 April 2009) Available online via the OhioLINK ETD Center

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Sacco, John D. "Validation of a System to Analyze Jump Kinetics during Musculoskeletal Rehabilitation." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1248456224.

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CUERO, NÚÑEZ TRINIDAD, and MOHAMED MOHAMED YASSEEN ELGHANDOUR MONA. "Moringa oleifera leaf meal as protein feed in goat’s diets: biomethane and carbon dioxide and fermentation kinetics”." Tesis de maestría, Universidad Autónoma del Estado de México, UAEM, 2017. http://hdl.handle.net/20.500.11799/67722.

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Durante la fermentación ruminal de los piensos, se producen grandes cantidades de gases de efecto invernadero (GEI) que hace en el ganado uno de los productores de gases de efecto invernadero más importantes. La Organización de las Naciones Unidas para la agricultura y la alimentación (FAO, 2006) informó que el sector ganadero representa aproximadamente el 18% del metano (CH4) y el 9%de las producciones de dióxido de carbono (CO2). Se han hecho muchos intentos para mitigar la emisión de ch4 de rumiantes, incluyendo la inclusión de levaduras (Elghandour et.al., 2017), sal de ácidos orgánicos, enzimas exógenas y aceites esenciales con resultados prometedores.

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Vallur, Aarthy C. "Kinetic analysis of the contribution of base flipping to the substrate specificity and catalytic activity of human alkyladenine dna glycosylase." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0008300.

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Thesis (Ph.D.)--University of Florida, 2004.
Typescript. Title from title page of source document. Document formatted into pages; contains 135 pages. Includes Vita. Includes bibliographical references.

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Adigun, Risikat Ajibola. "Insight into the Reactivity of Metastasis Inhibitor, Imidazolium trans-[tetrachloro (dimethyl sulfoxide)(imidazole)ruthenate(III)], with Biologically-active Thiols." PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/378.

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Imidazolium trans-[tetrachloro (dimethyl sulfoxide)(imidazole)ruthenate(III)], NAMI-A, is an experimental metastasis inhibitor whose specific mechanism of activation and action remains to be elucidated. In the nucleophilic and reducing physiological environment; it is anticipated that the most relevant and available reductants upon introduction of NAMI-A as a therapeutic agent will be the biologically-relevant free thiols. The kinetics and mechanisms of interaction of NAMI-A with biologically-active thiols cysteamine, glutathione, cysteine and a popular chemoprotectant, 2-mercaptoethane sulfonate (MESNA) have been studied spectrophotometrically under physiologically-relevant conditions. The reactions are characterized by initial reduction of NAMI-A with simultaneous formation of dimeric thiol and subsequent ligand exchange with water to various degrees as evidenced by Electospray Ionization Mass Spectrometry. Stoichiometry of reactions shows that one molecule of NAMI-A reacted with one mole of thiol to form corresponding disulfide cystamine, dimeric MESNA, oxidized glutathione and cystine. Observed rate constants, ko, for the reaction of NAMI-A with cysteamine, MESNA, GSH and cysteine were deduced to be 6.85 + 0.3 x 10-1, 9.4 + 0.5 x 10-2 , 7.42 + 0.4 x 10-3 and 3.63 + 0.3 x 10-2 s-1 respectively. Activation parameters determined from Arrhenius plots are indicative of formation of associative intermediates prior to formation of products. A negative correlation was obtained from the Brønsted plot derived from observed rate constants and the pKa of the different thiols demonstrating significant contribution of thiolate species towards the rate. In conclusion, interactions of NAMI-A with biologically-active thiols are kinetically and thermodynamically favored and should play significant roles in in vivo metabolism of NAMI-A.

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Ghazala, Suad. "Degradation kinetics of quality factors, their verification and optimization in a thermoprocessed simulated food system." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74358.

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A novel simulated food model (ascorbic acid, thiamine and a mixture of glucose and glycine) incorporating celite was developed. Basic kinetic parameters were established and the analysis of this data led to a reconsideration of the fundamental aspects relating the TDT and Arrhenius systems of evaluating kinetic parameters and their meaning. Heat penetration data was obtained for both conduction and convection systems, with the conduction system being characterized by parameters calculated from the heat penetration data. Stainless steel micro-capsules were used to isolate and obtain centerpoint nutrient destruction and compared it to the predictions of two computer models. Computer models were tested and verified for the conduction system and an optimization technique based on a multi-factor objective function evaluated.
Celite simulated a typical conduction system and the kinetics of quality factor degradation varied depending on composition. Centerpoint capsules worked well in evaluating nutrient destruction and provided a means for verifying computer simulations. Predictions from the Teixeira and Ball models indicated that the Teixeira model was a better process predictor. Multi-factor objective functions for maximizing nutrient retention were shown to work well in defining optimal conditions using the Teixeira program, while those based on the Ball model were indeterminate.

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Duz, Serkan. "3d Kinematic Analysis Of Three Different Punches In Amateur Boxing." Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613156/index.pdf.

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The main objective of this study was to determine differences, if any, in three-dimensional (3D) kinematic characteristics of the three principal punches (the jab, hook and uppercut) executed by novice, intermediate and elite level amateur boxers. Specifically, the kinematic variables related to the displacement, linear velocity and acceleration of the upper body segments, translational hand acceleration and vertical ground reaction force generated by boxers were analyzed. The subjects of this study composed of 10 novice, 9 intermediate, and 11 elite level amateur boxers. Ages of the subjects ranged from 18 to 34 years old. All subjects executed their punches toward a head-high target on a standard practice bag. The motions were captured with PhaseSpace real time optical tracking system with 8 high speed cameras at 240 fps. Then, the motions captured were analyzed to quantify the kinematic factors associated with each punch. The results showed that the uppercut punch generated larger linear shoulder, elbow and wrist velocity compared to the jab punch. Similarly, the uppercut punch generated larger linear shoulder, elbow and wrist acceleration compared to the hook and jab punches. Moreover, the uppercut and hook punches generated larger translational hand acceleration compared to the jab punch. As a conclusion, the results for all kinematic variables demonstrated that the type of punch executed was the major determinant of the magnitude of each factor studied. Moreover, the technique employed can significantly affect the resulting displacement, linear velocity and acceleration, and translational hand acceleration of the fist.

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Gokhale, Dipen P. "Kinematic analysis and animation of a variable geometry truss robot." Thesis, Virginia Tech, 1987. http://hdl.handle.net/10919/45677.

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In this thesis, forward and inverse kinematic equations are developed for a parallel, closed-loop manipulator known as the Variable Geometry Truss or VGT for short. Widely recognized as adaptive or collapsing structures for space and military applications, VGTs have not received due consideration as robotic manipulators. VGTs undoubtedly represent an important sector of future manipulator applications. VGTs are typically constructed using repeating identical cells or modules and they have exceptional stiffness to weight ratios.

The data obtained from solving the forward kinematic equations is used for animation of the VGT. For animation, three dimensional graphics software, graPHIGS is used. Additionally, the kinematic analysis equations are used to map out workspace of the VGT. An experiment is also carried out to verify the computational results.

Master of Science

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27

Pilson, Richard Adair. "The effect of temperature on denitrification kinetics and biological excess phosphorus removal in nutrient removal activated sludge systems in temperate climates (12°C - 20°C)." Master's thesis, University of Cape Town, 1995. http://hdl.handle.net/11427/22577.

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Filamentous bulking in nutrient (N & P) removal activated sludge systems is a problem of considerable magnitude - three quarters of 45 plants surveyed were found to have bulking sludges to the extent that sludge settleability (DSVI) was adversely affected. If filamentous organism proliferation could be controlled and thereby sludge settleability improved to below DSVI of 100 ml/g, then with provision for factors such as additional aeration capacity, between 50% and 7 5% more wastewater could be treated in existing nutrient removing activated sludge plants. Anoxic-aerobic (AA) or low F/M filaments appear to proliferate in activated sludge plants that incorporate biological nitrogen removal. From earlier research, Casey et al. (1992a) showed that the cause for AA filament proliferation lay in the denitrification behaviour of the N removal systems. They hypothesized that filamentous and floe-forming organisms have different denitrification behaviour - the former reducing nitrate only as far as nitrite whereas the latter reducing nitrate all the way to nitrogen gas via the denitrification intermediates nitrite, nitric oxide (NO) and nitrous oxide (N₂O). If nitrate and nitrite removal to nitrogen gas is not complete in the anoxic reactor, then, when conditions become aerobic, the accumulated denitrification intermediates, in particular NO, inhibit oxygen uptake in the floc-formers. The filaments do not experience this inhibition because by reducing nitrate only to nitrite, no denitrification intermediates accumulate in their cytoplasmic membrane and consequently they can successfully compete against the floe-formers and proliferate in the N removal systems. If denitrification is complete, no residual intracellular denitrification intermediates remain in the floc-formers. Therefore, when conditions become aerobic, the floc-formers are not inhibited in their oxygen uptake and can successfully compete against the filamentous organisms which cause the bulking.

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Концевой, А. Л., and С. А. Концевой. "Розрахунок кінетичних параметрів за дериватографічними даними." Thesis, Сумський державний університет, 2016. http://essuir.sumdu.edu.ua/handle/123456789/54457.

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Дериватографічне дослідження базується на нагріві зразка з постійною швидкістю зростання температури. Це дозволяє виявити і вивчити особливості екзо- і ендотермічних процесів хімічного перетворення. Крива термогравіметричного (ТГ) аналізу описує втрату маси зразка від температури (тобто отримана в неізотермічних умовах) і може замінити серію ізотермічних кривих залежності ступеня перетворення від часу, що дозволяє вивчити кінетичні закономірності процесу (топохімічного, наприклад).

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29

Mozdarani, Hossein. "Kinetics of X-ray induced chromatid aberrations in irradiated Gâ†2 normal human and ataxia-telangiectasia cells and the influence of DNA repair inhibitors." Thesis, University of St Andrews, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329904.

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30

Tinmark, Fredrik. "Analysis of elite golfers' kinematic sequence in full and partial shots." Thesis, Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:gih:diva-466.

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Aim
The purposes of the present study were, to determine if partial and full-swing shots performed by skilled golfers were organized in a proximal-to-distal sequencing (PDS) pattern and to examine the speed-summation effect at pelvis, upper torso and hand segments.

Method
Three-dimensional kinematic recordings of pelvis, upper torso, and hand were made while forty-seven skilled golfers stroke three different clubs a range of submaximal and maximal shot distances.

Results
This study showed a clear proximal-to-distal temporal relationship of movement onset and peak angular speed at the pelvis, upper torso and hand segments in the golf swing. The same temporal structure was evident at all test conditions, among different gender and level of expertise. Further, results revealed a summation effect of angular velocity from proximal-to-distal, with each succeeding segment generating a larger rotational speed than the proximal segment. However, the increment in speed from proximal-to-distal was different among gender and level of expertise. Conclusions The temporal relation of segment kinematics suggests a common PDS organization in partial and full-swing shots for skilled golfers. A speed-summation effect of segmental angular speed indicates that participants did utilize interaction torques in a proximal-to-distal manner. The role of the observed PDS organization and speed-summation effect in partial shots might be to improve accuracy and, potentially, golfers should concentrate on speed initially in learning the golf swing.

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Demetriou, Christodoulos S. "A PC implemented kinematic synthesis system for planar linkages." Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/101343.

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The purpose of this thesis is to develop a PC implemented kinematic synthesis system for four-bar and six-bar planar linkages using Turbo Pascal. CYPRUS is an interactive program that calculates and displays graphically the designed four-bar and six-bar linkages. This package can be used for three and four position synthesis of path generation, path generation with input timing, body guidance, and body guidance with input timing linkages. The package can also be used for function generation linkages where the user may enter a set of angle pairs or choose one of the following functions: tangent, cosine, sine, exponential, logarithmic, and natural logarithmic. The above syntheses can be combined to design linkages that produce more complex motion. For each kinematic synthesis case the code calculates a certain number of solutions. Then the designer chooses the most suitable solution for the particular application at hand. After a mechanism is synthesized, it can be animated for a check of the mechanical action. Watching this animation allows the designer to judge criteria such as clearances, forces, velocities and acceleration of the moving links. The software operates on an IBM PC or any other PC compatible. The language used is Turbo Pascal, an extremely effective tool and one of the fastest high level languages in compilation and execution time.
M.S.

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32

Lewer, N. "Bradford Non-Lethal Weapons Research Project (BNLWRP). Research Report 1." University of Bradford, 1997. http://hdl.handle.net/10454/3960.

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yes
The NLW database illustrates the extensive and eclectic literature regarding NLWs which covers the last few decades. It currently contains over 250 entries. It is important to have access not only to the more recent material, but also to earlier sources since many of the general debates and controversies have already been rehearsed, and lessons learnt from them are still relevant today. Yet, it is also vital to follow new developments of NLWs closely because rapidly changing technology is producing weapons whose implications for integration into military and civil police forces have yet to be clearly defined and understood. Of particular interest are not only NLW applications for war fighting, but opportunities for deployment in peace enforcement and peace keeping missions. These technologies span many bases including: psycho-chemicals; unmanned weapons platforms and delivery systems; biogenetics; acoustic and microwave weapons; biological and chemical weapons; laser systems; kinetic energy ballistics; dual purpose (lethal/non-lethal) weapons; and, sprays and foams which inhibit movement. The database will keep up to date on these developments and future reports will highlight new issues and debates surrounding them. With these rapid technological advances come a series of associated dangers and concerns including: the ethics of use; implications for weapons control and disarmament treaties; military doctrine; public accountability and guidelines; dangers of misuse and proliferation; and, research and development strategies. Using the database, and drawing from military and non-military sources, this report will select the main current issues and debates within the non-lethal community. Bearing in mind that many operations undertaken by military forces are now more akin to policing actions (such as peace support operations) there are lessons to be learnt by military units from civil police experience. There still remains a tension between perceived benign and malign intent both in NLW operational use and non-lethal research and development.

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33

Milani-Nejad, Nima. "Regulation of Cardiac Contraction in Health and Disease: Studies from Animal Models to Humans." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397225239.

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Tester, Jefferson W. "Fundamental studies of oxidation kinetics and salt precipitation in supercritical water: final NASA project report, volume 1: research summary." MIT Energy Lab, 1992. http://hdl.handle.net/1721.1/27221.

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35

Fazenbaker, Lisa Diane. "An In-Vitro Kinematic Biomechanical Evaluation of Two Surgical Techniques in Adolescent Idiopathic Scoliosis." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1335999724.

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He, Xingyu. "Long-term Light-activated Drug Delivery Systems." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1613752062550859.

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37

Xu, Mengyuan. "The Role of Shelterin Proteins in Telomere DNA Protection and Regulation." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1585760345643995.

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Nesbitt, Rebecca J. "Establishing Design Criteria for Anterior Cruciate Ligament Reconstruction." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1428048607.

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39

Herfat, Mohammadsafa T. "Characterizing the Ovine Stifle Model as a Preclinical Biomechanical Surrogate for the Human Knee." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1307104704.

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40

Speirs, Monique Merilyn. "Development and Use of Lipidomics and Proteomics Methods to Identify and Measure Pro-Survival Metabolic Pathways in Cancer." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7601.

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Throughout society’s continual war against cancer, we have attempted pharmacological intervention only to find that tumors develop modes of resistance. It is well known that genetics play an integral role in cancer. Technological advances have greatly improved our ability to study cancer biochemistry beyond the genome by measuring changes in the expression and activity of RNA, proteins, and lipids in experimental models and human patients. As our techniques and technology to perform cancer research progresses, it is becoming more evident that cancer cells develop stress tolerance mechanisms at multiple levels within the central dogma, including altering mRNA expression, enzyme concentrations, and functional activity of cellular proteins and lipids. In the first chapter, I review previous discoveries demonstrating the importance of metabolic reprogramming in cancer cells and how shifts in metabolic pathways contribute to cancer progression and therapeutic challenges. I discuss how mass spectrometry is a multifunctional research tool that can be used to identify global shifts in gene expression, identify oncogenic roles of specific metabolites and corresponding metabolic pathways, conduct enzyme activity assays, and understand the effects of drugs on cell signaling and metabolic flux through specific pathways. While metabolic reprogramming is a complex and multifaceted concept, the following chapters focus on two specific stress tolerance pathways of lipid and protein metabolism we have shown to significantly promote cancer cell evolution, proliferation, and drug resistance in models of human pancreatic and colon cancer. I describe novel mass spectrometry-based lipidomics and proteomics methods we developed to measure and determine the biological impact of these pathways in each model. I discuss the contributions we have made toward increasing general knowledge of metabolic reprogramming networks in cancer and how they may be targeted in more specific and effective manners to sensitize cancers to therapeutic drugs. Specifically, the second chapter entails our study of a pro-survival lipid metabolic pathway driven by the sphingolipid modifying enzyme sphingosine kinase in a panel of differentially reprogrammed pancreatic cancer subclones. The third chapter describes our novel kinetic proteomics approach to identify how the cellular degradation system autophagy is used to selectively remodel the proteome of colon tumor cells in a xenograft mouse model of colon cancer. Lastly, I discuss how these and other projects completed during my graduate work lay a foundation for ongoing research to further our fundamental understanding of cancer metabolism and treatment development.

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Perdomo, Joana L. "Mathematical Modeling of Blood Coagulation." Scholarship @ Claremont, 2016. https://scholarship.claremont.edu/hmc_theses/71.

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Blood coagulation is a series of biochemical reactions that take place to form a blood clot. Abnormalities in coagulation, such as under-clotting or over- clotting, can lead to significant blood loss, cardiac arrest, damage to vital organs, or even death. Thus, understanding quantitatively how blood coagulation works is important in informing clinical decisions about treating deficiencies and disorders. Quantifying blood coagulation is possible through mathematical modeling. This review presents different mathematical models that have been developed in the past 30 years to describe the biochemistry, biophysics, and clinical applications of blood coagulation research. This review includes the strengths and limitations of models, as well as suggestions for future work.

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42

Chung, Jae-Hoon. "Regulation of Human Cardiac Muscle Contraction and Relaxation in Health and Disease." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1522851185767187.

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43

Misko, Tessianna Misko. "The Natural and Pharmacological Inhibition of Ribonucleotide Reductase." Case Western Reserve University School of Graduate Studies / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case1537128885029723.

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44

Lobb, Kevin Alan. "Camphor derivatives in asymmetric synthesis: a synthetic, mechanistic and theoretical study." Thesis, Rhodes University, 2008. http://hdl.handle.net/10962/d1006770.

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A series of 3,3-ethylenedioxy-exo- and endo- bornyl esters have been prepared and subjected to α-benzylation using lithium diisopropylamide and benzyl bromide. In the exo-series of esters the diastereofacial selectivity of benzylation was found to improve (up to 34% d.e.) as the steric bulk of the O-alkyl group increased, whereas in the endo-series, a surprising decrease in stereoselectivity was observed as the steric bulk increased – an observation attributed to flexibility of the metal-coordinated endo-enolate system, compared to the relative rigidity of the exo analogues. The conformational options for each series was explored at the density functional theory level. Reductive cyclization of a range of specially prepared N-carbobenzyloxy-amino acid esters has been shown to afford the corresponding derivatives, contrary to previous reports that the cyclization is limited to the glycine derivative. The cyclization sequence has been explored in detail, and the yield has been shown to be critically dependent on the stereochemistry of the α-amino acid moiety. Moreover, it seems that reductive cyclization occurs more readily with the endo- rather than the exo-bornyl N-CBZ-amino acid esters. Molecular modelling of relevant transition states at the DFT levels indicates that L-amino acid-derived systems should cyclize preferably in the exo-series and D-amino acid-derived systems should cyclize preferably in the endo series. Studies of alkylation of an iminolactone system have reported an interesting anomaly - exo-methylation is observed while endo-alkylation predominates for larger alkyl groups. This has been studied in detail at the DFT level, and the anomaly is attributed to thermodynamic control in the methyl case, whereas kinetic control is the norm in this system. Preliminary computer modelling of the intramolecular rearrangement of a 3,3-xylylbornyl system at the HF/STO-3G level raised doubts concerning the structure assigned by Evans to one of the rearrangement products, prompting an X-ray crystallographic analysis and leading to the revision of its structure from a pinene to a camphene derivative. The previously elusive spiro[bornane-3,2’-indan]-2-exo-tosylate has been successfully isolated, and the kinetics of its ready decomposition to the two camphene products has been followed by 1H NMR spectroscopy. The endo-tosylate analogue, on the other hand, was found to be remarkably stable. Kinetic data obtained for rearrangement of this exo-bornyl tosylate have indicated the operation of tandem autocatalytic and pseudo-first-order transformations leading sequentially to the two isomeric camphene products. An extensive coset analysis of all possible rearrangement processes of the initially-formed cation formed from decomposition of the exo-tosylate has afforded a graph containing 336 classical cations (modelled at the AM1 and B3LYP levels) and 526 transition-state complexes (modelled at the AM1 level). This analysis afforded a viable 4-step classical mechanism connecting the first camphene product with the second. A more realistic study, involving non-classical carbocations, has afforded a graph of all possible (classical and non-classical) cations that could be formed by rearrangment of the initiallyformed cation. The resulting graph confirms that the only energetically feasible path corresponds to the classical mechanism, but simply involves two steps, including a novel, concerted Wagner-Meerwein – 6,2-hydride shift – Wagner-Meerwein rearrangement.

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45

Gizer, Gökhan [Verfasser]. "Role of Additives on the Kinetic and Thermodynamic Properties of Mg(NH2)2+LiH Reactive Hydride Composite / Gökhan Gizer ; Helmholtz-Zentrum Geesthacht, Institute of Materials Research, Department of Nanotechnolgy." Hamburg : Helmut-Schmidt-Universität, Bibliothek, 2020. http://d-nb.info/1213040604/34.

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46

Baity, Sean Marshall. "Development of a Next-generation Experimental Robotic Vehicle (NERV) that Supports Intelligent and Autonomous Systems Research." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/36102.

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Recent advances in technology have enabled the development of truly autonomous ground vehicles capable of performing complex navigation tasks. As a result, the demand for practical unmanned ground vehicle (UGV) systems has increased dramatically in recent years. Central to these developments is maturation of emerging mobile robotic intelligent and autonomous capability. While the progress UGV technology has been substantial, there are many challenges that still face unmanned vehicle system developers. Foremost is the improvement of perception hardware and intelligent software that supports the evolution of UGV capability. The development of a Next-generation Experimentation Robotic Vehicle (NERV) serves to provide a small UGV baseline platform supporting experimentation focused on progression of the state-of-the-art in unmanned systems. Supporting research and user feedback highlight the needs that provide justification for an advanced small UGV research platform. Primarily, such a vehicle must be based upon open and technology independent system architecture while exhibiting improved mobility over relatively structured terrain. To this end, a theoretical kinematic model is presented for a novel two-body multi degree-of-freedom, four-wheel drive, small UGV platform. The efficacy of the theoretical kinematic model was validated through computer simulation and experimentation on a full-scale proof-of-concept mobile robotic platform. The kinematic model provides the foundation for autonomous multi-body control. Further, a modular system level design based upon the concepts of the Joint Architecture for Unmanned Systems (JAUS) is offered as an open architecture model providing a scalable system integration solution. Together these elements provide a blueprint for the development of a small UGV capable of supporting the needs of a wide range of leading-edge intelligent system research initiatives.
Master of Science

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47

Jamieson, Quentin. "The Inactivation Mechanisms of Shaker IR and Kv2.1 Potassium Channels: Lessons from Pore Mutation." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1396357775.

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48

Tkachuk, M. M. "Research of the non-equilibrium of the diffuse layer for the description of the electrochemical kinetics near the rotating disk electrode by numerical solutions of the strict boundary problem." Thesis, БДМУ, 2022. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/19546.

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49

Abramo, Kristin N. "Building the Interphase Nucleus: A study on the kinetics of 3D chromosome formation, temporal relation to active transcription, and the role of nuclear RNAs." eScholarship@UMMS, 2020. https://escholarship.umassmed.edu/gsbs_diss/1099.

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Following the discovery of the one-dimensional sequence of human DNA, much focus has been directed on microscopy and molecular techniques to learn about the spatial organization of chromatin in a 3D cell. The development of these powerful tools has enabled high-resolution, genome-wide analysis of chromosome structure under many different conditions. In this thesis, I focus on how the organization of interphase chromatin is established and maintained following mitosis. Mitotic chromosomes are folded into helical loop arrays creating short and condensed chromosomes, while interphase chromosomes are decondensed and folded into a number of structures at different length scales ranging from loops between CTCF sites, enhancers and promoters to topologically associating domains (TADs), and larger compartments. While the chromatin organization at these two very different states is well defined, the transition from a mitotic to interphase chromatin state is not well understood. The aim of this thesis is to determine how interphase chromatin is organized following mitotic chromosome decondensation and to interrogate factors potentially responsible for driving the transition. First, I determine the temporal order with which CTCF-loops, TADs, and compartments reform as cells exit mitosis, revealing a unique structure at the anaphase-telophase transition never observed before. Second, I test the role of transcription in reformation of 3D chromosome structure and show that active transcription is not required for the formation of most interphase chromatin features; instead, I propose that transcription relies on the proper formation of these structures. Finally, I show that RNA in the interphase nucleus can be degraded with only slight consequences on the overall chromatin organization, suggesting that once interphase chromatin structures are achieved, the structures are stable and RNA is only required to reduce the mixing of active and inactive compartments. Together, these studies further our understanding of how interphase structures form, how these structures relate to functional activities of the interphase cell, and the stability of chromatin structures over time.

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50

Outada, Nisrine. "Complex Systems in Biology and Soft Sciences : Modeling by Hyperbolic and Kinetic Equations, Analytic and Numerical Problems A critical analysis towards research perspectives Reply to comments on “Modeling human behavior in economics and social science” A critical analysis towards research perspectives Reply to comments on “Modeling human behavior in economics and social science”." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS448.

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Cette thèse a pour objectif de développer une approche mathématique pour la modélisation des systèmes vivants en mettant l’accent sur les équations hyperboliques et cinétiques décrivant les systèmes multicellulaires en biologie, la dynamique de foule, et les comportements collectifs des individus en sciences sociales et économiques considérées comme des sciences comportementales, appelées parfois “sciences douces”. Plus précisément, les points traités dans cette thèse ont été les suivants : 1) Le développement de ce qu’on appelle la théorie cinétique des particules actives pour la dérivation d’une structure mathématique pour la modélisation des systèmes vivants, qui tient compte des caractéristiques et complexités de ces systèmes complexes, où la dynamique des entités est développée aussi sur la variable d’espace. Cette structure mathématique générale offre un cadre conceptuel pour la dérivation des modèles spécifiques correspondant à des classes de systèmes bien définies et remplace les approches classiques utilisées pour modéliser les systèmes inertes qui s’avèrent inappropriés pour la modélisation des systèmes vivants. 2) Le développement de méthodes mathématiques pour la dérivation de modèles à l’échelle macroscopique de type Keller-Segel et de type Cattaneo à partir d’une description cinétique basée sur la théorie des particules actives, ainsi que le développement et l’implémentation des schémas numériques préservant la limite asymptotique, en particulier des méthodes de volumes finis pour les systèmes de lois de conservations sont utilisées pour l’approximation des modèles macroscopiques. 3) L’application à la modélisation, l’analyse qualitative et les simulations des systèmes sociaux. Plus précisément les applications ont été adressées aux systèmes sociaux-économiques et à la dynamique comportementale de la foule en mettant en œuvre l’évacuation d’un espace dangereux où la géométrie est complexe et en tenant compte de la propagation du stress. Des simulations numériques ont été obtenues par un développement approprié des méthodes de Monte Carlo. 4) L’étude de la convergence de développement de Hilbert pour la dérivation d’équations macroscopiques à partir de la description mésoscopique basée sur la théorie cinétique des particules actives, et l’analyse qualitative liée à l’existence et l’unicité des solutions des systèmes cinétiques
This thesis tackles the challenging aim of developing a mathematical theory of living systems with focus on hyperbolic and kinetic equations, to multicellular systems in biology, crowd dynamics, and social sciences and economy viewed as behavioral sciences, occasionally called soft sciences. In more details, the following topics have been tackled: 1) Development of the theory and application of the kinetic theory of the scalled active particles, with the main objective of deriving a general mathematical structure, consistent with the complexity features of living systems, where the dynamics are developed over the space variable. This structure offers the conceptual background for the derivation of specific models corresponding to well-defined classes of systems and substitutes the field theories, which classically offers the natural support in the sciences of the inert matter that cannot be applied in the case of living systems. Applications have also motivated development of simulation tools. 2) Mathematical methods to derive macroscopic tissue equations, of Keller– Segel and Cattaneo type, from the underlying description at the microscopic scale delivered by kinetic type models and development of computational schemes towards simulations both of kinetic transport models and hyperbolic macroscopic models. In more details, finite volume methods for hyperbolic conservative laws equations have been developed for the simulations of macroscopic models. 3) Applications to modeling, qualitative analysis, and simulations of social systems. Applications have been addressed to social systems and behavioral crowd dynamics with a special focus on evacuation dynamics from venues with complex geometry with special focus to a dy- namics, where panic propagates. Simulations have been obtained by a suitable developments of the socalled Monte Carlo particle methods. 4) Analytical problems generated by the convergence of the Hilbert approach to the derivation of macroscopic equations from the kinetic theory approach, and a qualitative analysis related to existence and uniqueness of the solutions of the initial value problems of the kinetic systems

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Dissertations / Theses on the topic 'Kinetic researches'

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