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1
March, Alan Charles. "Computer automation of a novel ion-exchange process for the simultaneous recovery of lysozyme and avidin from chicken egg albumen". Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/29660.
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A three-column ion-exchange system was designed, fabricated and computer-automated to accommodate a novel 'elution looping' process developed by Dr. Tim Durance (U.B.C. Department of Food Science) during his doctoral studies on the recovery of lysozyme and avidin. This processing technique enhances the simultaneous recovery of these two pharmaceutically important proteins from chicken egg albumen. The processing system prototype was sized to handle throughput rates between approximately five and 300 liters per day of albumen to facilitate both laboratory and small commercial scale work. Very efficient use is made of the ion-exchange resin due to a two-column cascaded feed arrangement.
The processing control software was designed to provide flexibility and ease of operation in setting up new and existing method files, allowing for the selection of any column or group of columns to use and providing a 'staged-shutdown' approach toward handling columns fouled with congealed albumen during unattended operation. This approach attempts to maximize the productivity of the system even when one or two of the columns has become fouled with congealed albumen.Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate
2
Tailony, Ra'uf. "Ion exchange glass strengthening using microwave processing". University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1449764292.
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Yiu, Lai Kuen Candy. "Chinese character synthesis : towards universal Chinese information exchange". HKBU Institutional Repository, 2003. http://repository.hkbu.edu.hk/etd_ra/477.
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Shen, Mengzhe y 沈梦哲. "Parametric wavelength exchange and its application in high speed optical signal processing". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B42841616.
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Shen, Mengzhe. "Parametric wavelength exchange and its application in high speed optical signal processing". Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B42841616.
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Demos, Antonis Angelos. "The analysis of continuous time exchange rate data : testing and information processing". Thesis, Birkbeck (University of London), 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364528.
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ISHIKAWA, Yoshiharu y Fengrong LI. "Query Processing in a Traceable P2P Record Exchange Framework". Institute of Electronics, Information and Communication Engineers, 2010. http://hdl.handle.net/2237/14955.
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Heijmans, Franciscus R. C. "A computer simulation of the pulmonary microvascular exchange system - alveolar flooding". Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25099.
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Previous models of the pulmonary microvascular exchange system (28,29) have been restricted to the study of fluid and solute exchange between the pulmonary microcirculation, interstitial tissue space, and lymphatics. In severe pulmonary edema the capacities of the lymphatics and tissue space are exceeded. The fluid and solutes entering the interstitium from the circulation will, then, be transported Into the air space. The accumulation of fluid in the air space impairs the diffusion of gas (oxygen and carbon dioxide) between the air space and blood circulation; if this fluid accumulation is excessive a patient's health may be compromised.
In this thesis severe pulmonary edema is studied by including the air space as a fourth compartment into the interstitial model developed by Bert and Pinder (29).
A computer simulation of the four compartment (alveolar) model was developed on a digital computer. Tests of the model were made to study the effect of the parameters which were introduced into the alveolar model. These parameters include: a filtration coefficient that describes the alveolar membrane fluid conductivity, an extravascular fluid volume that represents the point at which fluid enters the air space, the alveolar fluid pressure at the onset of fluid flow into the air space, and the rate of alveolar fluid pressure change relative to an alveolar fluid volume change. For each case the dynamic response of the exchange system was recorded. In addition, two types of pulmonary edema were simulated: 1) hydrostatically induced edema, and 2) edema induced by changes to the fluid and solute permeability of the porous membrane separating the circulatory and interstitial compartments.
Due to the limited data available on the interaction of the air space with the other three compartments of the pulmonary microvascular exchange system, only partial verification of the appropriate range of values of the alveolar model parameters and the predictions of the simulations was possible. The alveolar model developed in this thesis is an initial approximation but appears to provide a satisfactory approach for the inclusion of the air space in the pulmonary microvascular exchange system.Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate
9
Martello, Rosanna. "Cloud storage and processing of automotive Lithium-ion batteries data for RUL prediction". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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Lithium-ion batteries are the ideal choice for electric and hybrid vehicles, but the high cost and the relatively short life represent an open issue for automotive industries. For this reason, the estimation of battery Remaining Useful Life (RUL) and the State of Health (SoH) are primary goals in the automotive sector. Cloud computing provides all the resources necessary to store, process and analyze all sensor data coming from connected vehicles in order to develop Predictive Maintenance tasks. This project describes the work done during my internship at FEV Italia s.r.l. The aims were designing an architecture for managing the data coming from a vehicle fleet and developing algorithms able to predict the SoH and the RUL of Lithium-ion batteries. The designed architecture is based on three Amazon Web Services: Amazon Elastic Compute Cloud, Amazon Simple Storage Service and Amazon Relational Database Service. After data processing and the feature extraction, the RUL and SoH estimations are performed by training two Neural Networks.
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Oller, Moreno Sergio. "Data processing for Life Sciences measurements with hyphenated Gas Chromatography-Ion Mobility Spectrometry". Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/523539.
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Recent progress in analytical chemistry instrumentation has increased the amount of data available for analysis. This progress has been encompassed by computational improvements, that have enabled new possibilities to analyze larger amounts of data. These two factors have allowed to analyze more complex samples in multiple life science fields, such as biology, medicine, pharmacology, or food science.
One of the techniques that has benefited from these improvements is Gas Chromatography - Ion Mobility Spectrometry (GC-IMS). This technique is useful for the detection of Volatile Organic Compounds (VOCs) in complex samples. Ion Mobility Spectrometry is an analytical technique for characterizing chemical substances based on the velocity of gas-phase ions in an electric field. It is able to detect trace levels of volatile chemicals reaching for some analytes ppb concentrations. While the instrument has moderate selectivity it is very fast in the analysis, as an ion mobility spectrum can be acquired in tenths of milliseconds. As it operates at ambient pressure, it is found not only as laboratory instrumentation but also in-site, to perform screening applications. For instance it is often used in airports for the detection of drugs and explosives. To enhance the selectivity of the IMS, especially for the analysis of complex samples, a gas chromatograph can be used for sample pre-separation at the expense of the length of the analysis.
While there is better instrumentation and more computational power, better algorithms are still needed to exploit and extract all the information present in the samples. In particular, GC-IMS has not received much attention compared to other analytical techniques. In this work we address some of the data analysis issues for GC-IMS: With respect to the pre-processing, we explore several baseline estimation methods and we suggest a variation of Asymmetric Least Squares, a popular baseline estimation technique, that is able to cope with signals that present large peaks or large dynamic range. This baseline estimation method is used in Gas Chromatography - Mass Spectrometry signals as well, as it suits both techniques. Furthermore, we also characterize spectral misalignments in a several months long study, and propose an alignment method based on monotonic cubic splines for its correction. Based on the misalignment characterization we propose an optimal time span between consecutive calibrant samples.
We the explore the usage of Multivariate Curve Resolution methods for the deconvolution of overlapped peaks and their extraction into pure components. We propose the use of a sliding window in the retention time axis to extract the pure components from smaller windows. The pure components are tracked through the windows. This approach is able to extract analytes with lower response with respect to MCR, compounds that have a low variance in the overall matrix
Finally we apply some of these developments to real world applications, on a dataset for the prevention of fraud and quality control in the classification of olive oils, measured with GC-IMS, and on data for biomarker discovery of prostate cancer by analyzing the headspace of urine samples with a GC-MS instrument.Els avenços recents en instrumentació química i el progrés en les capacitats computacionals obren noves possibilitats per l’anàlisi de dades provinents de diversos camps en l’àmbit de les ciències de la vida, com la biologia, la medicina o la ciència de l’alimentació. Una de les tècniques que s’ha beneficiat d’aquests avenços és la cromatografia de gasos – espectrometria de mobilitat d’ions (GC-IMS). Aquesta tècnica és útil per detectar compostos orgànics volàtils en mostres complexes. L’IMS és una tècnica analítica per caracteritzar substàncies químiques basada en la velocitat d’ions en fase gasosa en un camp elèctric, capaç de detectar traces d’alguns volàtils en concentracions de ppb ràpidament. Per augmentar-ne la selectivitat, un cromatògraf de gasos pot emprar-se per pre-separar la mostra, a expenses de la durada de l’anàlisi. Tot i disposar de millores en la instrumentació i més poder computacional, calen millors algoritmes per extreure tota la informació de les mostres. En particular, GC-IMS no ha rebut molta atenció en comparació amb altres tècniques analítiques. En aquest treball, tractem alguns problemes de l’anàlisi de dades de GC-IMS: Pel que fa al pre-processat, explorem algoritmes d’estimació de la línia de base i en proposem una millora, adaptada a les necessitats de l’instrument. Aquest algoritme també s’utilitza en mostres de cromatografia de gasos espectrometria de masses (GC-MS), en tant que s’adapta correctament a ambdues tècniques. Caracteritzem els desalineaments espectrals que es produeixen en un estudi de diversos mesos de durada, i proposem un mètode d’alineat basat en splines cúbics monotònics per a la seva correcció i un interval de temps òptim entre dues mostres calibrants. Explorem l’ús de mètodes de resolució multivariant de corbes (MCR) per a la deconvolució de pics solapats i la seva extracció en components purs. Proposem l’ús d’una finestra mòbil en el temps de retenció. Aquesta millora permet extreure més informació d’analits. Finalment utilitzem alguns d’aquests desenvolupaments a dues aplicacions: la prevenció de frau en la classificació d’olis d’oliva, mesurada amb GC-IMS i la cerca de biomarcadors de càncer de pròstata en volàtils de la orina, feta amb GC-MS.
11
Ligozio, Kevin. "Jini distributed key exchange and file transfer service with digital signatures /". Online version of thesis, 2004. https://ritdml.rit.edu/dspace/handle/1850/2812.
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Kammerer, Judith [Verfasser]. "Selective Polyphenol Recovery from By-Products of Plant Foodstuff Processing by Adsorption and Ion Exchange Technology / Judith Kammerer". Aachen : Shaker, 2011. http://d-nb.info/1071529005/34.
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Nallanchakravarthula, Sriramkumar. "Trading system design and implementation in OCEAN (Open Computation Exchange and Arbitration Network)". [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE0000579.
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Peintner, Daniel [Verfasser] y Harald [Akademischer Betreuer] Kosch. "Efficient Exchange and Processing of Semi-structured Data in the Embedded Domain / Daniel Peintner. Betreuer: Harald Kosch". Passau : Universitätsbibliothek der Universität Passau, 2014. http://d-nb.info/1064541186/34.
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MANOSSO, HELENA C. "Desenvolvimento de eletrodos de troca iônica eletroquímica para o tratamento de rejeitos contendo íons crômio ou césio". reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11439.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
16
Hoffman, John Jared. "PPerfGrid: A Grid Services-Based Tool for the Exchange of Heterogeneous Parallel Performance Data". PDXScholar, 2004. https://pdxscholar.library.pdx.edu/open_access_etds/2664.
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This thesis details the approach taken in developing PPerfGrid. Section 2 discusses other research related to this project. Section 3 provides general background on the technologies utilized in PPerfGrid, focusing on the components that make up the Grid services architecture. Section 4 provides a description of the architecture of PPerfGrid. Section 5 details the implementation of PPerfGrid. Section 6 presents tests designed to measure the overhead and scalability of the PPerfGrid application. Section 7 suggests future work, and Section 8 concludes the thesis.
17
Guamán, Novillo Ana Verónica. "Multivariate Signal Processing for Quantitative and Qualitative Analysis of Ion Mobility Spectrometry data, applied to Biomedical Applications and Food Related Applications". Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/349210.
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There are several applications where the measurement of VOC results to be useful, such as: toxic leaks, air quality measurements, explosive detection, monitoring of food and beverages quality, diagnosis of diseases, etc. Some of this applications claim for fast responses or even real time responses. In this context, there are few analytical techniques for performing gas phase analysis, among of them Ion Mobility Spectrometry (IMS).
IMS is a fast analytical device based on the time of flight of ions in a drift tube. The response of IMS lasts typically few seconds, but it can be even less than a second. This fast response has drifted its use towards novel applications, such as biomedical and food applications (bio-related applications). Nonetheless, it has also brought the need to analyze complex spectra with hundreds of compounds. In fact, tackling this disadvantage is the main focus of this thesis, where new algorithms for enhancing the IMS performance are investigated when are applied to bio-related applications.
Nonlinear behavior and charge competitions of IMS responses are important issues that need to be addressed. Both effects have a direct impact in the IMS spectra interpretation —especially when real dataset are studied. Additionally, the use of univariate spectra analysis, where peaks information is extracted manually, becomes unfeasible in bio-related applications. In this context, this work introduces multivariate methodologies focused on quantitative and qualitative analysis.
In the case of quantitative analysis, calibration models were built using univariate methodology, Partial Leas Squares (PLS) and Multivariate Curve Resolution techniques (MCR). The quantitative analysis aims tackling the main issues of IMS such as non linearities and mixture effect. Definitely, univariate techniques provides poor or overoptimistic results that minimize the impact of the IMS use. The results show a really improvement on the performance when multivariate techniques were used. Regarding the results between MCR and PLS, the main difference is the interpretability that offers MCR.
In the case of qualitative analysis, two different approaches were planned for building models for classes' discrimination. The first approach consisted on building a model through principal component analysis and linear discriminant analysis, besides of using robust cross validation methodology for obtaining reliable results. This methodology were implemented in samples of wine, where main motivation was found discrimination regarding to their origin. The results were fully satisfactory because the model was able to separate four groups with a high accuracy rate. The second approach involves the use of Multivarite Curve Resolution — Lasso algorithm for extracting pure components of samples from rats' breath and then use a feature selection technique for obtaining the most representative features subset. In this case, the objective of the application was to find a model that discriminate rats with sepsis from control rats. The results shows there were few pure components of IMS that generate a discriminatory model that means there are specific compounds in the breath linked with the disease.
Summarizing, the following proposal has as main objective resolving open issues in stand-alone IMS that are applied to the analysis of bio-related applications. Two major investigation lines were proposed in this thesis: (i) qualitative analysis and (ii) quantitative analysis. The qualitative analysis covers pre-processing algorithms and the developing of new methodologies for building models in bio-related applications. The quantitative analysis are focused on highlighting the importance of the use of multivariate techniques instead of univariate techniques. In order to reach the objectives of this thesis, a set of datasets were created, which are detailed on the content of this thesis. The results and main conclusions are deeply explained in the extended proposal.El objetivo de esta tesis es el desarrollo de nuevas metodologías en el procesado de señal multivariante en espectros IMS. En este trabajo se ha realizado una comparación entre tres espectrómetros IMS. Esta labor comparativa, mediante procesado multivariante, es prácticamente inédita en este ámbito. En este caso se realizó un estudio con 3 aminas y se determinó el límite de detección. Los resultados mostraron que los 3 espectrómetros tuvieron un rendimiento similar, a pesar de que sus condiciones de operación son distintas. Se propuso una técnica específica para eliminar ruido de baja frecuencia acoplado al espectro de IMS. Se observó que utilizar PCA o ICA (métodos multivariantes) mejora notablemente la relación señal ruido si se compara con las técnicas convencionales. Se ha estudiado el alineamiento de los espectros y se han propuesto soluciones basadas en los diferentes métodos del estado del arte. Se ha evidenciado que incluir compuestos de referencia para garantizar que el proceso de alineamiento es el adecuado es ventajoso. En el caso de que esto no fuese posible se aconseja realizar el alineamiento por etapas, primero un alineamiento en una misma muestra, y luego entre muestras. Se realizaron modelos cualitativos para diferenciar o discriminar clases a partir de medidas de IMS. Se propusieron dos modelos multivariantes con técnicas de validación cruzada. Los resultados obtenidos muestran el gran potencial de IMS en este sentido. Se evaluó el rendimiento cuantitativo de los IMS al utilizar métodos multivariantes y fueron comparados con métodos univariantes habituales en el ámbito de IMS. De los resultados obtenidos se observó que los modelos univariantes no son capaces de resolver comportamientos típicos de IMS como son el comportamiento no lineal y el efecto en mezclas. En este sentido las técnicas multivariantes mostraron mejores prestaciones. Se comparó la utilización de técnicas multivariantes que proyectan los datos en un nuevo subespacio como lo es PLS con técnicas de deconvolución como lo es MCR en sus dos versiones ALS y Lasso. Los resultados obtenidos fueron bastante similares, sin embargo MCR ofrece una ventaja importante ya que permite interpretar de mejor manera los resultados.
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Zhang, Mingqiang. "Morphological Characterization and Analysis of Ion-Containing Polymers Using Small Angle X-ray Scattering". Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/77256.
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Small angle X-ray scattering (SAXS) has been widely used in polymer science to study the nano-scale morphology of various polymers. The data obtained from SAXS give information about sizes and shapes of macromolecules, characteristic distances of partially ordered materials, pore sizes, and so on. The understanding of these structural parameters is crucial in polymer science in that it will help to explain the origin of various properties of polymers, and guide design of future polymers with desired properties.
We have been able to further develop the contrast variation method in SAXS to study the morphology of Nafion 117CS containing different alkali metal ions in solid state. Contrast variation allows one to manipulate scattering data to obtain desired morphological information. At room temperature, only the crystalline peak was found for Na⁺-form Nafion, while for Cs⁺-form Nafion only the ionic peak was observed. The utilization of one dimensional correlation function on different counterion forms of Nafion further demonstrates the necessity of contrast variation method in obtaining more detailed morphological information of Nafion. This separation of the ionic peak and the crystalline peak in Nafion provides a means to independently study the crystalline and ionic components without each other's effect, which could be further applied to other ionomer systems.
We also designed time resolved SAXS experiments to study the morphological development during solution processing Nafion. As solvent was removed from Nafion dispersion through evaporation, solid-state morphological development occurred through a variety of processes including phase-inversion, aggregation of interacting species (e.g., ionic functionalities), and crystallization of backbone segments. To probe the real-time morphological development during membrane processing that accurately simulates industrial protocols, a unique sample cell has been constructed that allows for through-film synchrotron SAXS data acquisition during solvent evaporation and film formation. For the first time, this novel experiment allows for a complete analysis of structural evolution from solution/dispersion to solid-state film formation, and we were able to show that the crystallites within Nafion develop later than the formation of ionic domains, and they do not reside in the cylindrical particles, but are dispersed in solution/dispersion.
Besides bulk morphology of Nafion, we have also performed Grazing Incident SAXS to study the surface morphology of Nafion. We were able to manipulate the surface morphology of Nafion via neutralizing H⁺-form Nafion with different large organic counterions, as well as annealing Nafion thin films under different temperatures. This not only allows to obtain more detailed information of the nano-structures in Nafion thin films, but also provides a means to achieve desired morphology for better fuel cell applications.
We have also been able to study the polymer chain conformation in solution via measuring persistence length by utilizing solution SAXS. Different methods have been applied to study the SAXS profiles, and the measured persistence lengths for stilbene and styrenic alternating copolymers range from 2 to 6 nm, which characterizes these copolymers into a class of semi-rigid polymers. This study allows to elucidate the steric crowding effect on the chain stiffness of these polymers, which provides fundamental understanding of polymer chain behaviors in solution.
Self-assembling in block copolymers has also been studied using SAXS. We established a morphological model for a multiblock copolymer used as a fuel cell material from General Motors®, and this morphological model could be used to explain the origins of the mechanical and transport properties of this material. Furthermore, several other block copolymers have been studied using SAXS, which showed interesting phase separated morphologies. These morphological data have been successfully applied to explain the origins of various properties of these block copolymers, which provide fundamental knowledge of structure-property relationship in block copolymers.Ph. D.
19
Davis, Brian Edward. "Characterization and calibration of stereolithography products and processes". Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/17677.
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MANOSSO, HELENA C. "Utilizacao dos trocadores inorganicos ZrP e TiP no tratamento de rejeitos industriais e radioativos". reponame:Repositório Institucional do IPEN, 2001. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10919.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
21
Lynn, Charity M. "Accuracy models for SLA build style decision support". Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/16832.
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Hibberd, Christopher J. "Development of non-vacuum and low-cost techniques for Cu(In, Ga)(Se, S)2 thin film solar cell processing". Thesis, Loughborough University, 2009. https://dspace.lboro.ac.uk/2134/5840.
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Solar photovoltaic modules provide clean electricity from sunlight but will not be able to compete on an open market until the cost of the electricity they produce is comparable to that produced by traditional methods. At present, modules based on crystalline silicon wafer solar cells account for nearly 90% of photovoltaic production capacity. However, it is anticipated that the ultimate cost reduction achievable for crystalline silicon solar cell production will be somewhat limited and that thin film solar cells may offer a cheaper alternative in the long term. The highest energy conversion efficiencies reported for thin film solar cells have been for devices based around chalcopyrite Cu(In, Ga)(Se, S)2 photovoltaic absorbers. The most efficient Cu(In, Ga)(Se, S)2 solar cells contain absorber layers deposited by vacuum co-evaporation of the elements. However, the cost of ownership of large area vacuum evaporation technology is high and may be a limiting factor in the cost reductions achievable for Cu(In, Ga)(Se, S)2 based solar cells. Therefore, many alternative deposition methods are under investigation. Despite almost thirty companies being in the process of commercialising these technologies there is no consensus as to which deposition method will lead to the most cost effective product. Non-vacuum deposition techniques involving powders and chemical solutions potentially offer significant reductions in the cost of Cu(In, Ga)(Se, S)2 absorber layer deposition as compared to their vacuum counterparts. A wide range of such approaches has been investigated for thirty years and the gap between the world record Cu(In, Ga)(Se, S)2 solar cell and the best devices containing non-vacuum deposited absorber layers has closed significantly in recent years. Nevertheless, no one technique has demonstrated its superiority and the best results are still achieved with some of the most complex approaches. The work presented here involved the development and investigation of a new process for performing one of the stages of non-vacuum deposition of Cu(In, Ga)(Se, S)2 absorber layers. The new process incorporates copper into an initial Group III-VI precursor layer, e.g. indium gallium selenide, through an ion exchange reaction performed in solution. The ion exchange reaction requires only very simple, low-cost equipment and proceeds at temperatures over 1000°C lower than required for the evaporation of Cu under vacuum. In the new process, indium (gallium) selenide initial precursor layers are immersed in solutions containing Cu ions. During immersion an exchange reaction occurs and Cu ions from the solution exchange places with Group III ions in the layer. This leads to the formation of an intimately bonded, laterally homogeneous copper selenide – indium (gallium) selenide modified precursor layer with the same morphology as the initial precursor. These modified precursor layers were converted to single phase chalcopyrite CuInSe2 and Cu(In, Ga)Se2 by annealing with Se in a tube furnace system. Investigation of the annealing treatment revealed that a series of phase transformations, beginning at low temperature, lead to chalcopyrite formation. Control of the timing of the Se supply was demonstrated to prevent reactions that were deemed detrimental to the morphology of the resulting chalcopyrite layers. When vacuum evaporated indium (gallium) selenide layers were used as initial precursors, solar cells produced from the absorber layers exhibited energy conversion efficiencies of up to 4%. While these results are considered promising, the devices were characterised by very low open circuit voltages and parallel resistances. Rapid thermal processing was applied to the modified precursor layers in an attempt to further improve their conversion into chalcopyrite material. Despite only a small number of solar cells being fabricated using rapid thermal processing, improvements in open circuit voltage of close to 150mV were achieved. However, due to increases in series resistance and reductions in current collection only small increases in solar cell efficiency were recorded. Rapid thermal processing was also used to demonstrate synthesis of single phase CuInS2 from modified precursor layers based on non-vacuum deposited indium sulphide. Non-vacuum deposition methods provide many opportunities for the incorporation of undesirable impurities into the deposited layers. Analysis of the precursor layers developed during this work revealed that alkali atoms from the complexant used in the ion exchange baths are incorporated into the precursor layers alongside the Cu. Alkali atoms exhibit pronounced electronic and structural effects on Cu(In, Ga)Se2 layers and are beneficial in low concentrations. However, excess alkali atoms are detrimental to Cu(In, Ga)Se2 solar cell performance and the problems encountered with cells produced here are consistent with the effects reported in the literature for excess alkali incorporation. It is therefore expected that further improvements in solar cell efficiency might be achieved following reformulation of the ion exchange bath chemistry.
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CHEPCANOFF, VERA. "Separacao e recuperacao de cromio e outros elementos de valor em solucoes de trabalho e residuos industriais de galvanoplastia por troca ionica". reponame:Repositório Institucional do IPEN, 2001. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10909.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
24
Tessier, Sean Michael. "Ontology-based approach to enable feature interoperability between CAD systems". Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41118.
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Data interoperability between computer-aided design (CAD) systems remains a major obstacle in the information integration and exchange in a collaborative engineering environment. The standards for CAD data exchange have remained largely restricted to geometric representations, causing the design intent portrayed through construction history, features, parameters, and constraints to be discarded in the exchange process. In this thesis, an ontology-based framework is proposed to allow for the full exchange of semantic feature data. A hybrid ontology approach is proposed, where a shared base ontology is used to convey the concepts that are common amongst different CAD systems, while local ontologies are used to represent the feature libraries of individual CAD systems as combinations of these shared concepts. A three-branch CAD feature model is constructed to reduce ambiguity in the construction of local ontology feature data. Boundary representation (B-Rep) data corresponding to the output of the feature operation is incorporated into the feature data to enhance data exchange.
The Ontology Web Language (OWL) is used to construct a shared base ontology and a small feature library, which allows the use of existing ontology reasoning tools to infer new relationships and information between heterogeneous data. A combination of OWL and SWRL (Semantic Web Rule Language) rules are developed to allow a feature from an arbitrary source system expressed via the shared base ontology to be automatically classified and translated into the target system. These rules relate input parameters and reference types to expected B-Rep objects, allowing classification even when feature definitions vary or when little is known about the source system. In cases when the source system is well known, this approach also permits direct translation rules to be implemented. With such a flexible framework, a neutral feature exchange format could be developed.
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SORDO, FILHO GIOVANNI del. "Estudo da adsorção de íons metálicos em caulinita para água de reuso". reponame:Repositório Institucional do IPEN, 2015. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26394.
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Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Andén, Olivia. "Structural basis of modulation by pH and calcium in a ligand-gated ion channel". Thesis, KTH, Genteknologi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299889.
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Pentameriska ligandstyrda jonkanaler (pLGICs) är avgörande för omvandlingen av kemisk till elektrisk signalöverföring i djurs nervsystem. Dysfunktion i dessa kanaler har visat sig vara kopplad till flera sjukdomar inklusive epilepsi, schizofreni, Alzheimers och autism, vilket gör dem till en måltavla för en mängd olika läkemedel. Att studera eukaryota kanaler är dock mycket utmanande, så upptäckten av prokaryota homologer, som är mycket lättare att studera, har därmed bidragit mycket till förståelsen för struktur och funktion hos proteiner i denna familj. I detta projekt producerades och renades en prokaryotisk pLGIC kallad DeCLIC från Escherichia coli. Strukturell bestämning av kanalen genomfördes med användning av kryo-elektronmikroskopi vid lågt pH och i närvaro av kalcium. En elektrontäthet med 3.4 Å upplösning uppnåddes och jämfördes med tidigare bestämda strukturer vid olika förhållanden i ett försök att bestämma hur proteinets struktur moduleras av kalcium och pH. Resultaten visar flera skillnader i kanalens konformation i närvaro och frånvaro av kalcium såväl som vid olika pH-värden. Dessutom antyder analys av den bestämda elektrontätheten ett möjligt intermediärt tillstånd vid lågt pH i närvaro av kalcium.Pentameric ligand-gated ion channels (pLGICs) are crucial for the conversion of chemical to electrical signaling in the nervous system of mammals. Dysfunction in these channels has been found to be connected to several diseases including epilepsy, schizophrenia, Alzheimer’s, and autism, making them the target of a wide variety of therapeutic agents. However, studying eukaryotic channels is challenging so the discovery of prokaryotic homologs that are much easier to study has thus greatly helped in the understanding of the structure and function in this family of proteins. In this project, a prokaryotic pLGIC called DeCLIC was produced and purified from Escherichia coli. Structural determination of the channel was pursued using cryo-electron microscopy at a low pH and in the presence of calcium. An electron density at 3.4 Å resolution was achieved and compared to previously determined structures at different conditions in an attempt to determine the structural modulation of calcium and pH. Results show multiple differences in channel conformation in the presence and absence of calcium as well as in different pH conditions. Furthermore, analysis of the determined electron density suggests a possible intermediate state at low pH in the presence of calcium.
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YAMAURA, MITIKO. "Particao de actinideos e de produtos de fissao de rejeito liquido de alta atividade". reponame:Repositório Institucional do IPEN, 1999. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10731.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Mashima, Daisuke. "Safeguarding health data with enhanced accountability and patient awareness". Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45775.
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Several factors are driving the transition from paper-based health records to electronic health record systems. In the United States, the adoption rate of electronic health record systems significantly increased after "Meaningful Use" incentive program was started in 2009. While increased use of electronic health record systems could improve the efficiency and quality of healthcare services, it can also lead to a number of security and privacy issues, such as identity theft and healthcare fraud. Such incidents could have negative impact on trustworthiness of electronic health record technology itself and thereby could limit its benefits.
In this dissertation, we tackle three challenges that we believe are important to improve the security and privacy in electronic health record systems. Our approach is based on an analysis of real-world incidents, namely theft and misuse of patient identity, unauthorized usage and update of electronic health records, and threats from insiders in healthcare organizations. Our contributions include design and development of a user-centric monitoring agent system that works on behalf of a patient (i.e., an end user) and securely monitors usage of the patient's identity credentials as well as access to her electronic health records. Such a monitoring agent can enhance patient's awareness and control and improve accountability for health records even in a distributed, multi-domain environment, which is typical in an e-healthcare setting. This will reduce the risk and loss caused by misuse of stolen data. In addition to the solution from a patient's perspective, we also propose a secure system architecture that can be used in healthcare organizations to enable robust auditing and management over client devices. This helps us further enhance patients' confidence in secure use of their health data.
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Corell, Simon. "A Recurrent Neural Network For Battery Capacity Estimations In Electrical Vehicles". Thesis, Linköpings universitet, Medie- och Informationsteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-160536.
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This study is an investigation if a recurrent long short-term memory (LSTM) based neural network can be used to estimate the battery capacity in electrical cars. There is an enormous interest in finding the underlying reasons why and how Lithium-ion batteries ages and this study is a part of this broader question. The research questions that have been answered are how well a LSTM model estimates the battery capacity, how the LSTM model is performing compared to a linear model and what parameters that are important when estimating the capacity. There have been other studies covering similar topics but only a few that has been performed on a real data set from real cars driving. With a data science approach, it was discovered that the LSTM model indeed is a powerful model to use for estimation the capacity. It had better accuracy than a linear regression model, but the linear regression model still gave good results. The parameters that implied to be important when estimating the capacity were logically related to the properties of a Lithium-ion battery.En studie över hur väl ett återkommande neuralt nätverk kan estimera kapaciteten hos Litium-ion batteri hos elektroniska fordon, när en en datavetenskaplig strategi har använts.
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Pomareda, Sesé Victor. "Signal Processing Approaches to the Detection and Localization of Gas Chemical Sources using Partially Selective Sensors". Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/119727.
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Due to recent progress, higher-order chemical instrumentation provides large amounts of data which need automated processing in order to extract relevant information. In most cases, the raw signals or spectra are too complex for manual analysis. The ability to detect, identify and quantitate chemical substances in gas phase in field operations is required in a huge number of applications. Among them, I would like to highlight the need for chemical sensing on diverse humanitarian, safety and security applications. In these cases, it becomes extremely important to continuously monitor the environments where chemicals are spread in order to be ready to act when abnormal events are discovered.
In most critical scenarios the sample can not just be taken to the laboratory and analyzed, since an immediate answer is needed. In some other scenarios, the exploration of the area must be performed because the localization of the gas source or material of interest is unknown. This exploration can be performed using multiple mobile sensors in order to localize the chemical source or material.
Different sensing technologies have been successfully used to detect and identify different chemical substances (gases or volatile compounds). These compounds could be either toxic or hazardous, or they can be signatures of the materials to be detected, for instance, explosives or drugs.
Among these technologies, mobility based analyzers provide fast responses with high sensitivity.
However, IMS instruments are not exempt of problems. Typically, they provide moderate selectivity, appearing overlapped peaks in the spectra. Moreover, the presence of humidity makes peaks wider, thus worsening the resolving power and the resolution. Furthermore, the response of IMS is non-linear as substance concentration increases and more than one peak can appear in the spectra due to the same compound.
In the present thesis, these problems are addressed and applications using an Ion Mobility Spectrometer (IMS) and a Differential Mobility Analyzer (DMA) are shown. It is demonstrated that multivariate data analysis tools are more effective when dealing with these technologies.
For the first time, multivariate data analysis tools have been applied to a novel DMA. It is shown that DMA could be established as a good instrumentation for the detection of explosives and the detection and quantitation of VOCs.
Furthermore, Multivariate curve resolution Alternating Least Squares (MCR-ALS) is shown to be suitable to analyze IMS spectra qualitatively when interfering chemicals appear in the spectra and even when their behaviour is non-linear. Partial Least Squares (PLS) methods are demonstrated to work properly for the quantitative analysis of these signals; from this analysis the chemical concentrations of the target substances are obtained.
It is also demonstrated in this thesis that the quantitative measurements from these sensors can be integrated in a gas source localization algorithm in order to improve the localization of the source in those scenarios where it is required. It is shown that the new proposal works significantly better in cases where the source strength is weak. This is illustrated presenting results from simulations generated under realistic conditions.
Moreover, real-world data were obtained using a mobile robot mounting a photo ionization detector (PID). Experiments were carried out under forced ventilation and turbulences in indoors and outdoors environments. The results obtained validate the simulation results and confirm that the new localization algorithm can effectively operate in real environments.Debido a los progresos recientes, la instrumentación química genera mayores volúmenes de datos los cuales requieren de un procesado automático con la finalidad de extraer la información relevante, ya que un análisis manual no suele ser viable debido a la elevada complejidad de los datos. La habilidad de detectar, identificar y cuantificar sustancias químicas en fase gas en operaciones de campo es requerida en un gran número de aplicaciones. Entre ellas, aplicaciones humanitarias y de seguridad. En estos casos, la monitorización continua de los entornos es extremadamente importante, ya que se debe estar alerta de eventos anormales. En los escenarios más críticos, debe realizarse una exploración del área porque la posición de la fuente de gas de interés es desconocida. Esta exploración puede realizarse usando múltiples robots. Diferentes tecnologías de sensores se han aplicado con éxito a la detección e identificación de diferentes sustancias químicas (gases o compuestos volátiles). Estos compuestos pueden ser tóxicos, peligrosos, o precursores de explosivos o drogas. De entre estas tecnologías, los analizadores basados en movilidad iónica (IMS) proporcionan rápidas respuestas con gran sensibilidad. Sin embargo, estos instrumentos no están exentos de problemas. Típicamente, proporcionan una moderada selectividad, apareciendo picos solapados en los espectros. Además, la presencia de humedad provoca que los picos se ensanchen, así empeorando la resolución. Además, la respuesta de IMS es no lineal al incrementar la concentración y es posible que más de un pico debido al mismo compuesto aparezca en el espectro. En la presente tesis se trata con estos problemas y se demuestra que las herramientas de análisis de datos multivariantes son más efectivas que las herramientas típicas univariantes al tratar con tecnologías de movilidad iónica (IMS y DMA), especialmente para el análisis cualitativo y cuantitativo de sus espectros. Además, se demuestra que las medidas cuantitativas pueden integrarse de manera efectiva en un algoritmo de localización de fuentes químicas. Los resultados obtenidos (simulaciones realistas y datos reales) muestran que el algoritmo desarrollado durante la tesis puede funcionar especialmente bien en situaciones en las que la potencia de emisión de la fuente a detectar sea débil.
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VASCONCELLOS, MARI E. de. "Aproveitamento de ítrio e lantânio de um carbonato de terras raras de baixo teor em cério, de um carbonato de ítrio e de um óxido de terras ítricas". reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11383.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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SENEDA, JOSE A. "Separação e recuperação de chumbo-208 dos resíduos de tório terras raras gerados na unidade piloto de purificação de nitrato de tório". reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11424.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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BABINSKI, MARLY. "Idades isocronicas Pb/Pb e geoquimica isotopica de Pb das rochas carbonaticas do grupo Bambui na porcao sul da bacia do Sao Francisco". reponame:Repositório Institucional do IPEN, 1993. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10339.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares, Sao Paulo
34
Rogstadius, Jakob. "Visualizing the Ethiopian Commodity Market". Thesis, Linköping University, Department of Science and Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-19564.
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The Ethiopia Commodity Exchange (ECX), like many other data intensive organizations, is having difficulties making full use of the vast amounts of data that it collects. This MSc thesis identifies areas within the organization where concepts from the academic fields of information visualization and visual analytics can be applied to address this issue.Software solutions are designed and implemented in two areas with the purpose of evaluating the approach and to demonstrate to potential users, developers and managers what can be achieved using this method. A number of presentation methods are proposed for the ECX website, which previously contained no graphing functionality for market data, to make it easier for users to find trends, patterns and outliers in prices and trade volumes of commodieties traded at the exchange. A software application is also developed to support the ECX market surveillance team by drastically improving its capabilities of investigating complex trader relationships.Finally, as ECX lacked previous experiences with visualization, one software developer was trained in computer graphics and involved in the work, to enable continued maintenance and future development of new visualization solutions within the organization.
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QUEIROZ, CARLOS A. da S. "Terras raras: fracionamento, purificação e controle analítico". reponame:Repositório Institucional do IPEN, 1988. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11634.
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Dissertacao (Mestrado)
IEA/D
Instituto de Quimica, Universidade de Sao Paulo - IQ/USP
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Boutiche, Mohamed. "Stabilité physico-chimique des smectites et de l'illite en présence de solutions chargées en électrolytes : étude expérimentale à 150°C". Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL057N.
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Les interactions chimiques entre des solutions utilisées dans les boues de forage, et différents types d'argiles ont été étudiées dans des conditions P, T proches de celles des forages (150°C) afin de déterminer les conséquences éventuelles sur la stabilité des argilites. Le travail a été conduit essentiellement de manière expérimentale, en utilisant différentes solutions: eau pure, NaOH (pH 8, 10, 12), KCl (0,1, 1, 2 mol. /l), eau de mer et K₂CO₃, et des argiles à forte et faible proportion de feuillets gonflants (smectite (Na, Na-Ca, Ca) interstratifiés illite-smectite). Les produits de réaction ont été étudiés par diffraction des rayons X, et microsonde électronique. Les feuillets de smectites montrent une série de transformations (échange en site interfoliaire, fermeture de feuillets, hydrolyse), qui ne conduisent pas cependant à la formation de nouveaux minéraux sauf dans le cas de traitement en présence de K₂CO₃ à 150°C (formation de zéolites). L’échange du cation interfoliaire est fonction de la nature du cation, de la concentration des cations dans les solutions, des constantes d'échange et du rapport liquide/solide. Dans les solutions diluées (<1 mol. /l), l'échange est partiel et a pour conséquence l'obtention de smectites à garnitures interfoliaires mixtes qui présentent des états d'hydratation variés. L'hydrolyse, plus forte pour la smectite sodique que la calcique, conduit à une perte du fer octaédrique
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Adeogun, Oluseun. "Informatics for devices within telehealth systems for monitoring chronic diseases". Thesis, Cranfield University, 2011. http://dspace.lib.cranfield.ac.uk/handle/1826/6493.
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Preliminary investigation at the beginning of this research showed that informatics on point-of-care (POC) devices was limited to basic data generation and processing. This thesis is based on publications of several studies during the course of the research. The aim of the research is to model and analyse information generation and exchange in telehealth systems and to identify and analyse the capabilities of these systems in managing chronic diseases which utilise point-of-care devices. The objectives to meet the aim are as follows: (i) to review the state-of-the-art in informatics and decision support on point-of-care devices. (ii) to assess the current level of servitization of POC devices used within the home environment. (iii) to identify current models of information generation and exchange for POC devices using a telehealth perspective. (iv) to identify the capabilities of telehealth systems. (v) to evaluate key components of telehealth systems (i.e. POC devices and intermediate devices). (vi) to analyse the capabilities of telehealth systems as enablers to a healthcare policy. The literature review showed that data transfer from devices is an important part of generating information. The implication of this is that future designs of devices should have efficient ways of transferring data to minimise the errors that may be introduced through manual data entry/transfer. The full impact of a servitized model for point-of-care devices is possible within a telehealth system, since capabilities of interpreting data for the patient will be offered as a service (c.f. NHS Direct). This research helped to deduce components of telehealth systems which are important in supporting informatics and decision making for actors of the system. These included actors and devices. Telehealth systems also help facilitate the exchange of data to help decision making to be faster for all actors concerned. This research has shown that a large number of capability categories existed for the patients and health professionals. There were no capabilities related to the caregiver that had a direct impact on the patient and health professional. This was not surprising since the numbers of caregivers in current telehealth systems was low. Two types of intermediate devices were identified in telehealth systems: generic and proprietary. Patients and caregivers used both types, while health professionals only used generic devices. However, there was a higher incidence of proprietary devices used by patients. Proprietary devices possess features to support patients better thus promoting their independence in managing their chronic condition. This research developed a six-step methodology for working from government objectives to appropriate telehealth capability categories. This helped to determine objectives for which a telehealth system is suitable.
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Sule, Pushkar Anant. "Studies of chemical speciation of trace metals in natural waters using an on-line electrochemical cell and ion exchange system". Thesis, 1991. http://hdl.handle.net/1957/38060.
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Jamal, Yousuf 1973. "Investigating the Use of Ion Exchange Resins for Processing Biodiesel Feedstocks". Thesis, 2012. http://hdl.handle.net/1969.1/148043.
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Ion exchange resins, commonly used in water treatment, demonstrate promise for the production of biodiesel from biomass feedstocks. The goal of this presented PhD research is to investigate novel uses of ion exchange resins for processing biodiesel feedstocks. Specifically, this research explored using ion exchange resins to remove free fatty acids (FFA) from soybean and waste cooking oils, catalyze transesterification of soybean oil, and catalyze in-situ conversion of dried algal biomass to biodiesel and other recoverable organics.
The effect of temperature, moisture content, mixing rate, and resin drying on deacidification of soybean oil with 5% oleic acid feedstock was explored using Dowex Monosphere MR-450 UPW within a batch reactor. The resins were observed to remove up to 83 +/- 1.3% of FFA from soybean oil with less than 5% moisture content while operated at a 20% resin loading at 50 degrees C while mixing at 550 rpm. Once operation characteristics impacting deacidification were evaluated, a series of experiments were carried out to demonstrate the use of mixed bed resin to remove FFA from waste cooking oils. An investigation of wash solutions capable of regenerating the resins was also carried out. Using methanol to regenerate the resins resulted in more than 40% FFA removal over three regeneration cycles, highlighting the utility of resin regeneration as a cost saving measure.
Transesterification of soybean oil on Amberlyst A26-OH, a basic ion exchange resin, in the presence of excess methanol was carried out to determine the mechanism of the reaction occurring on the surface. A batch reactor approach was used and reactions were carried out with and without FFA present in the soybean oil feed stock at a 20% resin loading at 50 degrees C while mixing at 550 rpm. When FFA was present in the feedstock and methanol is present in excess, the rate constant for methanol consumption increased. Based upon model fitting, the rate constant of methanol consumption was determined to be 2.08 x 10^-7 /sec with FFA absent and 5.39 x 10^-4/sec when FFA is present when the Eley-Rideal model was used to fit the data.
In-situ conversion of dried algal biomass to biodiesel and other recoverable organics was investigated using a batch reaction system with 1 gram of algae. The system was operated with 40:60 methanol:hexane as the solvent system operated at 50 degrees C while mixing at 550 rpm over a range of catalyst loadings. The highest observed ester yield, approximately 60% yield (37 mg_ester/g_algae), was observed when air dried algae was reacted with a 20% resin. An evaluation of the reaction products showed a mixture of esters, phytol, alcohols, and ketones; highlighting the complexity of the reactions occurring during in-situ biomass conversion.
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Herdan, David Errol. "A cryptographically secure protocol for key exchange". Thesis, 2014. http://hdl.handle.net/10210/12037.
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M.Sc. (Computer Science)Since the emergence of electronic communication, scientists have strived to make these communication systems as secure as possible. Classical cryptographical methods provided secrecy, with the proviso that the courier delivering the keys could be trusted. This method of key distribution proved to be too inefficient and costly. 'Cryptographical renaissance' was brought about with the advent of public key cryptography, in which the message key consists of a pair of mathematically complementary keys, instead of the symmetric keys of its forerunner. Classical cryptographical techniques were by no means obsolete, as the idea of using 'hybrid' systems proved to be very effective, by using the tedious public key techniques to allow both parties to share a secret, and the more efficient symmetric algorithms to actually encrypt the message. New technology leads, however, to new difficulties and the problems of key management now arose. Various protocols started emerging as solutions to the key distribution problem, each with their own advantages and disadvantages. The aim of this work is to critically review these protocols, analyse the shortfalls and attempt to design a protocol which will overcome these shortfalls. The class of protocol reviewed are the so-called 'strong authentication' protocols, whereby interaction between the message sender and recipient is required.
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Galeb, Abduljalil D. S. "Use of ion-exchange and direct osmotic concentration technologies for processing cantaloupe juice". Thesis, 1993. http://hdl.handle.net/1957/26050.
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Jamal, Yousuf. "Applications of Highly Cross Linked Mixed Bed Ion Exchange Resins in Biodiesel Processing". 2009. http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-6984.
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Biofuels are a promising solution to society's quest for sustainable
energy. In the transportation sector, biodiesel is the leading alternative diesel
fuel currently in use today. However, the current global and domestic production
of biodiesel is far below the petro-diesel consumption and demand. To
increase the availability of biodiesel in the market, new methods of biodiesel
production must be developed to take advantage of the plentiful low quality
waste derived feed stocks that currently present problems to biodiesel
production using conventional methods. This research presents one new
approach based upon using heterogeneous highly cross linked mixed bed solid
phase catalysts to facilitate the production of biodiesel from feed stocks with
high concentrations of free fatty acids (FFA). The performance of the
heterogeneous mixed bed catalysts method developed in this research was
evaluated and optimized for catalyst concentration and reaction duration while
the mixing rate, reaction temperature, initial FFA composition of the feed stock
and the alcohol-to-oil molar ratio were kept constant.
The presented method reduces the FFA content of the starting feed
stock while limiting the release of water into the reaction. Through
experimentation, it was found that FFA removal with the mixed bed resin is due
to ion exchange with the quaternary ammonium functional group and not
catalysis to form esters. A model describing the heterogeneous processing method is presented. The outcome of this research is the development of a new
processing method that can be used to create biodiesel from poor quality raw
feed stock materials.
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Van, Niekerk G. J. "A model for transparent data exchange in layered manufacturing". Thesis, 2008. http://hdl.handle.net/10210/855.
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The primary aim of this dissertation is to provide a platform and format-neutral exchange mechanism for Layered Manufacturing (LM) and Telemanufacturing. The current exchange standard is the Stereolithography (STL) file format. The format is notoriously prone to error and frequently causes problems during the process-planning stage. The format exclusively uses a triangular boundary representation as a mathematical model and therefore lacks accuracy for models that exhibit curved features [Van00]. The goal of this thesis is therefore two-fold. Firstly, a short-term solution needs to be implemented as a stopgap measure, while a long-term solution is realised. The long-term solution will hopefully fill the communication gap caused by the STL format. A short-term solution needs to extend the capabilities of the STL format. This will compensate for the discrepancies and will allow the STL format to keep up with the requirements of the industry, while a more permanent solution is developed. In this thesis, a stopgap measure in the form of STL-Extended is proposed. STL-Extended or STL-E is a technique that redefines the semantic properties of redundant information in the existing STL file. This allows additional information to be embedded within a STL file and facilitates the storage of models more accurately. The main aim of STL-E is to remain backwards compatible with legacy hardware and software. Although this does not address the flaws that the format exhibits, it provides the most transparent integration possible. A long-term solution is proposed in the form of the Data Exchange Framework for Layered Manufacturing (DEF4LM or just DEF). This is not a new LM file format, but a platform that would allow any format that is used by the industry to potentially become an exchange standard between designer and bureau. In essence, the platform redefines the mathematical model (representation technique) as the common denominator between abstractions, as opposed to the computer model (file format). DEF4LM constitutes a four-layer architecture, which includes the Data Layer, Implementation Layer, System Layer and the Application Layer. The Data Layer represents the actual computer model being used and serves as the carrier medium for the model. The Implementation Layer consists of a descriptor and a properties file. These two elements are used to describe the syntax and the semantics of a specific file format. The various data structures are extracted and passed to the System Layer, which in turn, passes the extracted data structures to the Application Layer. The Application Layer includes the LM process-planning system, as well as the hardware and controlling software. A complementary study also conducted as part of this thesis, investigates the feasibility of a genetic algorithm to generate tool-paths for extrusion-based LM technology. The technique evolves unique tool-paths and is guided by a fitness function that includes elements that optimise for surface quality and material deposition.Prof. E.M. Ehlers
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Kaever, Peter, Wolfgang Oertel, Axel Renno, Peter Seidel, Markus Meyer, Markus Reuter y Stefan König. "A Versatile Sensor Data Processing Framework for Resource Technology". 2021. https://htw-dresden.qucosa.de/id/qucosa%3A75233.
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Die Erweiterung experimenteller Infrastrukturen um neuartige Sensor eröffnen die Möglichkeit, qualitativ neuartige Erkenntnisse zu gewinnen. Um diese Informationen vollständig zu erschließen ist ein Abdecken der gesamten Verarbeitungskette von
der Datenauslese bis zu anwendungsbezogenen Auswertung erforderlich. Eine Erweiterung bestehender wissenschaftlicher Instrumente beinhaltet die strukturelle und zeitbezogene Integration der neuen Sensordaten in das Bestandssystem. Das hier vorgestellte Framework bietet durch seinen flexiblen Ansatz das Potenzial, unterschiedliche Sensortypen in unterschiedliche, leistungsfähige Plattformen zu integrieren. Zwei unterschiedliche Integrationsansätze zeigen die Flexibilität dieses Ansatzes, wobei einer auf die Steigerung der Sensitivität einer Anlage zur Sekundärionenmassenspektroskopie und der andere auf die Bereitstellung eines Prototypen zur Untersuchung von Rezyklaten ausgerichtet ist. Die sehr unterschiedlichen Hardwarevoraussetzungen und Anforderungen der Anwendung bildeten die Basis zur Entwicklung eines flexiblen Softwareframeworks. Um komplexe und leistungsfähige Applikationsbausteine bereitzustellen wurde eine Softwaretechnologie entwickelt, die modulare Pipelinestrukturen mit Sensor- und Ausgabeschnittstellen sowie einer Wissensbasis mit entsprechenden Konfigurations- und Verarbeitungsmodulen kombiniert.:1. Introduction
2. Hardware Architecture and Application Background
3. Software Concept
4. Experimental Results
5. Conclusion and OutlookNovel sensors with the ability to collect qualitatively new information offer the potential to improve experimental infrastructure and methods in the field of research technology. In order to get full access to this information, the entire range from detector readout data transfer over proper data and knowledge models up to complex application functions has to be covered. The extension of existing scientific instruments comprises the integration of diverse sensor information into existing hardware, based on the expansion of pivotal event schemes and data models. Due to its flexible approach, the proposed framework has the potential to integrate additional sensor types and offers migration capabilities to high-performance computing platforms. Two different implementation setups prove the flexibility of this approach, one extending the material analyzing capabilities of a secondary ion mass spectrometry device, the other implementing a functional prototype setup for the online analysis of recyclate. Both setups can be regarded as two complementary parts of a highly topical and ground-breaking unique scientific application field. The requirements and possibilities resulting from different hardware concepts on one hand and diverse application fields on the other hand are the basis for the development of a versatile software framework. In order to support complex and efficient application functions under heterogeneous and flexible technical conditions, a software technology is proposed that offers modular processing pipeline structures with internal and external data interfaces backed by a knowledge base with respective configuration and conclusion mechanisms.:1. Introduction 2. Hardware Architecture and Application Background 3. Software Concept 4. Experimental Results 5. Conclusion and Outlook
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Mukherjee, Parna. "Relative permeation of ions in reverse osmosis processes using ion exchange selectivity data : theoretical approach and experimental validation /". Diss., 2002. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3073985.
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Blakney, Gregory Terrell. "Investigations of biological interactions by hydrogen deuterium exchange Fourier transform ion cyclotron mass spectrometry novel methods, automated analysis and data reduction /". Thesis, 2003. http://wwwlib.umi.com/cr/utexas/fullcit?p3110730.
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Santos, Bjorn Sanchez. "Liquid-phase Processing of Fast Pyrolysis Bio-oil using Pt/HZSM-5 Catalyst". Thesis, 2013. http://hdl.handle.net/1969.1/149605.
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Recent developments in converting biomass to bio-chemicals and liquid fuels provide a promising sight to an emerging biofuels industry. Biomass can be converted to energy via thermochemical and biochemical pathways. Thermal degradation processes include liquefaction, gasification, and pyrolysis. Among these biomass technologies, pyrolysis (i.e. a thermochemical conversion process of any organic material in the absence of oxygen) has gained more attention because of its simplicity in design, construction and operation. This research study focuses on comparative assessment of two types of pyrolysis processes and catalytic upgrading of bio-oil for production of transportation fuel intermediates. Slow and fast pyrolysis processes were compared for their respective product yields and properties. Slow pyrolysis bio-oil displayed fossil fuel-like properties, although low yields limit the process making it uneconomically feasible. Fast pyrolysis, on the other hand, show high yields but produces relatively less quality bio-oil.
Catalytic transformation of the high-boiling fraction (HBF) of the crude bio-oil from fast pyrolysis was therefore evaluated by performing liquid-phase reactions at moderate temperatures using Pt/HZSM-5 catalyst. High yields of upgraded bio-oils along with improved heating values and reduced oxygen contents were obtained at a reaction temperature of 200°C and ethanol/HBF ratio of 3:1. Better quality, however, was observed at 240 °C even though reaction temperature has no significant effect on coke deposition. The addition of ethanol in the feed has greatly attenuated coke deposition in the catalyst. Major reactions observed are esterification, catalytic cracking, and reforming. Overall mass and energy balances in the conversion of energy sorghum biomass to produce a liquid fuel intermediate obtained sixteen percent (16 wt.%) of the biomass ending up as liquid fuel intermediate, while containing 26% of its initial energy.
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Sarurkar, Vishram A. "An Algorithm For Isolating Targeted Ions In Paul Traps". Thesis, 1998. http://etd.iisc.ernet.in/handle/2005/2186.
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Song, Zhibin. "Modeling and simulation of heat of mixing in li ion batteries". Thesis, 2015. http://hdl.handle.net/1805/7971.
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Indiana University-Purdue University Indianapolis (IUPUI)Heat generation is a major safety concern in the design and development of Li ion batteries (LIBs) for large scale applications, such as electric vehicles. The total heat generation in LIBs includes entropic heat, enthalpy, reaction heat, and heat of mixing. The main objective of this study is to investigate the influence of heat of mixing on the LIBs and to understand whether it is necessary to consider the heat of mixing during the design and development of LIBs. In the previous research, Thomas and Newman derived methods to compute heat of mixing in LIB cells. Their results show that the heat of mixing cannot be neglected in comparison with the other heat sources at 2 C rate. In this study, the heat of mixing in different materials, porosity, particle sizes, and charging/discharging rate was investigated. A COMSOL mathematical model was built to simulate the heat generation of LIBs. The LIB model was based on Newman’s model. LiMn2O4 and LiCoO2 were applied as the cathode materials, and LiC6 was applied as the anode material. The results of heat of mixing were compared with the other heat sources to investigate the weight of heat of mixing in the total heat generation. The heat of mixing in cathode is smaller than the heat of mixing in anode, because of the diffusivity of LiCoO2 is 1 ×10-13 m2/s, which is larger than LiC6's diffusivity 2.52 × 10-14 m2/s. In the comparison, the heat of mixing is not as much as the irreversible heat and reversible heat, but it still cannot be neglected. Finally, a special situation will be discussed, which is the heat of mixing under the relaxation status. For instance, after the drivers turn off their vehicles, the entropy, ix enthalpy and reaction heat in LIBs will stop generating, but the heat will still be generated due to the release of heat of mixing. Therefore, it is meaningful to investigate to see if this process has significant influence on the safety and cycle life of LIBs.
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Henderson, Macey Leigh. "Living kidney donor follow-up in a statewide health information exchange: health services utilization, health outcomes and policy implications". Diss., 2016. http://hdl.handle.net/1805/11007.
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Indiana University-Purdue University Indianapolis (IUPUI)Living donors have contributed about 6,000 kidneys per year in the past 10 years, but more than 100,000 individuals are still waiting for a kidney transplant. Living kidney donors undergo a major surgical procedure without direct medical benefit to themselves, but comprehensive follow-up information on living donors’ health is unfortunately limited. Expert recommendations suggest capturing clinical information beyond traditional sources to improve surveillance of co-morbid conditions from living kidney donors. Currently the United Network for Organ Sharing is responsible for collecting and reporting follow-up data for all living donors from U.S. transplant centers. Under policy implemented in February of 2013, transplant centers must submit follow-up date for two years after donation, but current processes often yield to incomplete and untimely reporting. This dissertation uses a statewide Health Information Exchange as a new clinical data source to 1) retrospectively identify a cohort of living kidney donors, 2) understand their follow-up care patterns, and 3) observe selected clinical outcomes including hypertension, diabetes and post-donation renal function.