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1
Moazzami, Farzad. "Capacity Enhancement in Aeronautical Channels by MIMO Technology." International Foundation for Telemetering, 2011. http://hdl.handle.net/10150/595803.
Повний текст джерелаАнотація:
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, NevadaThis paper shows how the application of MIMO (multiple-input multiple-output) communication methods can enhance telemetry systems. The main contribution of MIMO to the communication systems is improving spectral efficiency by exploiting spatial diversity of multiple antennas. For communications using high order QAM modulated signals, a blind MIMO equalizer is proposed in earlier works. In this work the possibility of adapting blind MIMO equalizer to iNET problems is explored. In addition, MIMO equalization is adapted to operate as a successive interference cancellation (SIC) scheme to improve the quality of received signal in a high interference environment by capturing and cancelling the interferer.
2
Messina, Giuseppe. "Advanced Techniques for Image Analysis and Enhancement." Thesis, Università degli Studi di Catania, 2011. http://hdl.handle.net/10761/190.
Повний текст джерелаАнотація:
The research activities, described in this thesis, have been mainly focused on images analysis and quality enhancement. Specifically the research regards the study and development of algorithms for color interpolation, contrast enhancement and red-eye removal, which have been exclusively oriented to mobile devices. Furthermore an images analysis for forgeries identification and image enhancement, usually directed by investigators (Forensic Image Processing) has been conducted. The thesis is organized in three main parts: Image Processing for Embedded Devices; Image Analysis and Enhancement; Forensics Image Processing.Le attivita' di ricerca, descritte in questa tesi, sono state principalmente focalizzate sull'analisi delle immagini ed il miglioramento della qualita'. In particolare la ricerca riguarda lo studio e lo sviluppo di algoritmi di interpolazione del colore, miglioramento del contrasto e rimozione degli occhi rossi, che sono stati esclusivamente sviluppati per l'utilizzo su dispositivi "mobile". Inoltre e' stata documentata un analisi delle immagini per l'identificazione dei falsi e per il miglioramento della qualita' immagini, a fini investigativi (Forensics Image Processing). La tesi e' organizzata in tre parti: Image Processing for Embedded Devices; Image Analysis and Enhancement; Forensics Image Processing.
3
Sezgin, Emre. "Itmem - Information Technology Management Enhancement Model: Assessment Of Information Technology Use In Organizations." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612353/index.pdf.
Повний текст джерелаАнотація:
This study proposes a new model for the assessment of information technology (IT) use in public and private companies, which is called ITMEM- Information Technology Management Enhancement Model. This model aims to assist decision making processes in information technology management. For this purpose, a tool is developed to explore strengths and weaknesses of a company in IT use. The model was developed upon a three-folded structure including (1) academic studies in technology management, (2) best practices which are developed for control over operations and processes including COBIT, CMMI and ITIL, and (3) standards about IT management and IT security. The conceptual framework of ITMEM is based on technology management process assessment model of M.J. Gregory. Methodological triangulation approach is adopted for the model for retrieving valid and reliable results. Triangulation consists of (1) semi structured interview, (2) presented company documents and (3) questionnaire developed upon relevant academic researches, best practices and standards. ITMEM was practiced on ten domestic and experienced companies in software &development and manufacturing industries which were appraised in or in progress of being appraised in CMMI. The study revealed the benefits and deficiencies of IT use in the company. It also provided information for decision makers about IT value within companies, and demonstrated the effects of best practices and standards over IT use.The reported findings should be valuable assets to researchers studying on IT management and IT use in organizations.
4
Su, Yu-Hao. "Power Enhancement of Piezoelectric Technology based Power Devices by Using Heat Transfer Technology." Thesis, Cachan, Ecole normale supérieure, 2014. http://www.theses.fr/2014DENS0025/document.
Повний текст джерелаАнотація:
L’objectif de cette étude est d’améliorer les performances des transformateurs piézoélectriques en terme de courant de sortie et de puissance pour des applications d’alimentation DC/DC, grâce à la gestion de l’échauffement. Le courant de sortie des transformateurs piézoélectriques, et donc la puissance transmise, sont directement liés à la vitesse de vibration qui pour des valeurs élevées engendre des pertes et une forte élévation de température. Cette élévation excessive de la température a comme conséquence le changement des caractéristiques du transformateur et plus particulièrement la diminution du facteur de qualité Q. Ainsi cela entraine une limite structurelle de la puissance transmise du transformateur. Une solution pour augmenter le courant de sortie est l’utilisation d’un redresseur doubleur de courant, qui grâce à 2 inductances permet, à courant de charge donné, de diminuer la vitesse de vibration du transformateur, mais ne permet pas de régler le problème d’échauffement du transformateur. Dans cette thèse nous proposons des moyens d’évacuation de la chaleur ainsi que le choix de l’environnement dans lequel le transformateur devra fonctionner. L’influence de différents systèmes de refroidissement d’un convertisseur DC/DC à base transformateur piézoélectrique est étudiée. L’étude thermique du transformateur piézoélectrique multicouche polarisé en épaisseur et ayant des électrodes circulaires met en évidence un comportement non linéaire. Une plaque vibrante piézoélectrique est d’abord envisagée pour créer un flux d’air qui augmente l’évacuation de chaleur par convection, puis un module de refroidissement utilisant l’effet thermoélectrique. Les mesures montrent que la première solution est plus avantageuse car elle améliore sensiblement les performances du transformateur pour un coût énergétique très faible. Une étude thermique par éléments finis complète cette étude, montrant que l’approche par schéma électrique est pertinente. La puissance que peut délivrer le transformateur sur une charge optimale est encore augmentée. Enfin, ce travail montre qu’en combinant les dispositifs de refroidissement tout en respectant la condition de température inférieure à 55°C, le rendement du convertisseur reste raisonnable (70%) et la puissance disponible peut doubler dans le meilleur des casThe objective of this study was to increase the output current and power in a piezoelectric transformer (PT) based DC/DC converter by adding a cooling system. It is known that the output current of PT is limited by temperature build-up because of losses especially when driving at high vibration velocity. Excessive temperature rise will decrease the quality factor Q of piezoelectric component during the operational process. Simultaneously the vibration energy cannot be increased even if under higher excitation voltage. Although connecting different inductive circuits at the PT secondary terminal can increase the output current, the root cause of temperature build-up problem is not solved.This dissertation presents the heat transfer technology to deal with the temperature build-up problem. With the heat transfer technology, the threshold vibration velocity of PT can be increased and thus the output current and output power (almost three times).Furthermore, a comparison between heat transfer technology and current-doubler rectifier applied to the piezoelectric transformer based DC/DC converter was also studied. The advantages and disadvantages of the proposed technique were investigated. A theoretical-phenomenological model was developed to explain the relationship between the losses and the temperature rise. It will be shown that the vibration velocity as well as the heat generation increases the losses. In our design, the maximum output current capacity can increase 100% when the operating condition of PT temperature is kept below 55°C. The study comprises of a theoretical part and experimental proof-of-concept demonstration of the proposed design method
5
Geving, Brad David. "Enhancement of stereolithography technology to support building around inserts." Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/16799.
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6
Claudel, Remi. "Seakeeping enhancement bylengthening a ship." Thesis, KTH, Marina system, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-234835.
Повний текст джерелаАнотація:
In this study, a tentative assessment of a passive solution for pitch decrease, namely the increase in length of the studied ship, is made. The hull form of the lengthened version of the ship is derived from the reference hull form after utilization of Lackenby’s sectional area curve transformation through a prismatic coefficient change (Reference [3]), and utilization of a sectional area curve “swinging” induced by a change of longitudinal position of the centre of buoyancy. Following this, and after a complementary mass estimate of the lengthened version, seakeeping calculations are made and show a significant decrease in pitch, from almost 35% for low sea states to 20% for relatively high sea states. To conclude this study, operability for classic NATO frigate missions have been calculated and the decrease in pitch induces a slight gain in operability for the lengthened version.
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Mohammed, Afzal U. R. "Solubility enhancement of poorly water soluble drugs using liposome technology." Thesis, Aston University, 2005. http://publications.aston.ac.uk/11022/.
Повний текст джерелаАнотація:
The aim of this work is to investigate the various parameters that could control the encapsulation of lipophilic drugs and investigate the influence of the physical properties of poorly water-soluble drugs on bilayer loading. Initial work investigated on the solubilisation of ibuprofen, a model insoluble drug. Drug loading was assessed using HPLC and UV spectrophotometric analysis. Preliminary studies focused on the influence of bilayer composition on drug loading to obtain an optimum cholesterol concentration. This was followed up by studies investigating the effect of longer alkyl chain lipids, unsaturated alkyl chain lipids and charged lipids. The studies also focused on the effects of pH of the hydration medium and addition of the single chain surfactant a-tocopherol. The work was followed up by investigation of a range of insoluble drugs including flurbiprofen, indomethacin, sulindac, mefenamic acid, lignocaine and progesterone to investigate the influence of drugs properties and functional group on liposomal loading. The results show that no defined trend could be obtained linking the drug loading to the different drug properties including molecular weight, log P and other drug specific characteristics. However, the presence of the oppositely charged lipids improved the encapsulation of all the drugs investigated with a similar effect obtained with the substitution of the longer chain lipids. The addition of the single chain surfactant a-tocopherol resulted in enhancement of drug loading and possibly is governed by the log P of the drug candidate. Environmental scanning-electron microscopy (ESEM) was used to dynamically follow the changes in liposome morphology in real time during dehydration thereby providing a alternative assay of liposome formulation and stability. The ESEM analysis clearly demonstrated ibuprofen incorporation enhanced the stability of PC:Chol liposomes.
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Cheng, Liang. "Innovative ground enhancement by improved microbially induced CaCO3 precipitation technology." Thesis, Cheng, Liang (2012) Innovative ground enhancement by improved microbially induced CaCO3 precipitation technology. PhD thesis, Murdoch University, 2012. https://researchrepository.murdoch.edu.au/id/eprint/15329/.
Повний текст джерелаАнотація:
The possibility of using microbiological processes to improve the mechanical properties of soil by undisturbed in-situ application has gained attention over recent years. This study has contributed to the technology of biocement, based on microbially induced carbonate precipitation (MICP), for the purpose of soil reinforcement application. MICP involves both the hydrolysis of urea by bacterial urease enzyme and calcium carbonate precipitation in the presence of dissolved calcium ions.
Other previously published approaches were based on saturated flow (submersed flow), which is accomplished by pumping solutions from an injection point to a recovery point which is limited exclusively to water saturated soil. This work describes a new variation of in-situ soil reinforcement technology by using surface percolation via – for example – spray irrigation onto dry, free draining ground, such as dunes or dykes.
In order to accomplish bacterial immobilization by surface percolation, it was necessary to alternately percolate bacterial suspension and cementation solution (CaCl2 and urea) to form sequential solution layers within the sand columns. By allowing Ca2+ ions diffusion between each layer bacterial immobilization could be enhanced from 30% to 80%. For a limited number of about 3 to 4 treatments this novel application method of cementation allowed homogeneous strength over the depth of the entire 1 m sand column.
Although the strength was homogenous, CaCO3 analysis showed that about 3 times less crystals were precipitated in the top layer compared to the bottom layers suggesting differences in efficiency of the calcite crystal to provide strength. This work demonstrated that this efficiency of calcite crystals was related to the pore water content of the continuously drained column with less water content enabling more efficient strength formation.
The geotechnical properties of bio-cemented sand samples under different degrees of saturation confirmed that higher strength could be obtained at lower degrees of saturation. To our knowledge, this study was the first study to demonstrate that the calcite crystals formed under a lower degree of saturation had more crystals formed in the contact points, contributing to the strength of the cemented samples. These preferred crystal formation was caused by the retained cementation solution situated in the form of menisci between sand particles at low degree of saturation. Scanning electron microscopy supported the idea that lower water contents lead to selective positioning of crystals at the bridging points between sand grains.
After biocementation treatment, fine sand samples exhibited significant increase in cohesion from 1.1 to 280 kPa and friction angle from 23o to 41o. Similar improvements were also obtained for coarse sand samples. Overall, fine sand sample indicated higher cohesion but lower friction angle than coarse sand samples having similar CaCO3 content.
The performance of cementation in large (2 m) laboratory scale trials indicated that subsequent treatments of more 4 times in fine sand caused clogging close to the injection end, resulting in limited cementation depth less than 1 m. This clogging problem was not observed in the 2 m treated coarse sand column, which had strength varying between 850 to 2067 kPa. This showed that the surface percolation technology was more applicable for coarse sand soil.
The laboratory large scale application (80 L) of fine sand cementation indicated that relatively homogenous cementation in the horizontal direction could be achieved with 80% of cemented sand having strength between 2 to 2.5 MPa. This suggested that although the liquid infiltration flow paths could not be controlled in the surface percolation method, self-adjusting flow paths were triggered by the changed internal flow resistance caused by the precipitated crystals, favoring the homogeneous cementation.
A simple mathematical model demonstrated that the cementation depth is dependent on the infiltration rate of cementation solution and the immobilized urease activity. Higher infiltration rate and lower urease activity will enable in deeper cementation. The model also predicted that repeated treatments will enhance sand clogging close to the injection point.
The traditional production of ureolytic bacteria used for biocementation is very expensive, because of strictly sterile processing. This study described the sustainable, non-sterile production of urease enzyme using activated sludge as inoculum. By using selective conditions (high pH and high ammonia concentration) for the target ureolytic bacteria plus the presence of urea as the enzyme substrate, highly active ureolytic bacteria, physiologically resembling Bacillus pasteurii were enriched and continuously produced from chemostat operation of the bioreactor. When using a pH of 10, and about 0.17 M urea in a yeast extract based medium ureolytic bacteria developed under aerobic chemostat operation at hydraulic retention times of about 10 h with urease levels of about 60 U/ml culture. This activity is six times higher than required for successful biocementation. The protein rich yeast extract medium could be replaced by commercial milk powder or by lysed activated sludge, which could make the industrial production less costly.
A method of in-situ production of urease activity was developed. This method involved providing selective growth medium to allow ureolytic bacteria to proliferate and produce urease activity in-situ of sand column. The aerobic ureolytic bacteria inoculum could only be enriched in unsaturated coarse sand column, where sufficient oxygen was available. However, high urease activities of 20 and 10 U/mL were obtained by growing soil bacteria under aerobic and anaerobic conditions respectively. The successful enrichment of highly urease active bacteria under anaerobic conditions could allow the in-situ production of urease activity at water logged soils. The in-situ produced urease activities by the enriched soil ureolytic bacteria were sufficient to allow successful cementation of fine (>500 kPa) and coarse (>1000 kPa) sand columns. The strength and CaCO3 analysis indicated that the common obstacle of surface clogging in deeper fine sand column was avoided, explained by avoiding bacterial accumulation at the top of the column.
In combination, all findings of the present study imply that the cost of MICP technology can be reduced by optimizing the conditions for effective crystals precipitation by providing low saturation conditions when the cementation is operated. The cost reduction can also be achieved by producing urease activity more economically by omitting the requirement of sterilization (non-sterile cultivation) and bioreactor (in-situ growth). These are expected to make this technology more readily acceptable for field applications.
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Lin, Qingfen. "Enhancement, Extraction, and Visualization of 3D Volume Data." Doctoral thesis, Linköping : Univ, 2003. http://www.bibl.liu.se/liupubl/disp/disp2003/tek824s.pdf.
Повний текст джерела
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Mansour, Heba Fathy. "Dissolution rate enhancement of poorly water-soluble drugs using lyophilisation technology." Thesis, University of Strathclyde, 2010. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=14503.
Повний текст джерела
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Austin-Crowe, Joseph W. "Analogue-to-digital conversion and image enhancement using neuron-mos technology." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2000. https://ro.ecu.edu.au/theses/1342.
Повний текст джерелаАнотація:
This thesis describes the development of two novel circuits that use a newly developed technology, that of neuron-MOS, for the purposes of analogue-to-digital conversion and image enhancement. Neuron-MOS has the potential to reduce both the complexity and number of transistors required for analogue and digital circuits. A reduced area, low transistor-count- analogue-to-digital converter that is suitable for inclusion in a massively parallel array of identical image processing elements is developed. Supporting the function of the array some fundamental image enhancement operations, such as edge enhancement, are examined exploiting the unique features of neuron-MOS technology.
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Baccare, Grace. "Genetic Enhancement, Hyperagency, and Humanity. An Investigation of the Implications." Thesis, Boston College, 2018. http://hdl.handle.net/2345/bc-ir:108028.
Повний текст джерелаАнотація:
Thesis advisor: Jeffrey BloechlThe genetic enhancement the human genome would be humanity’s most extreme attempt in the quest for hyperagency, and will have negative implications for our sense of humanity. Hyperagency is an extreme over-expression of our own human agency; everything is transparent, subject to our control and manipulation, and in accordance with our own interests. Modern era philosophical theories in subjectivity and agency have developed, evolved, and responded to advancements in science and technology over the past few centuries, and have all contributed to the current shift in understanding of our own humanity, influencing the rise of hyperagency in the postmodern world. The act of manipulating an organism’s genetic material for the purposes of changing and modifying its characteristics is referred to as genetic modification. The term genetic enhancement is more specifically indicative of the process of modifying nonpathological, or non-disease related genes. Genetic enhancement, in the form of germline engineering especially, exhibits a dangerous attitude of hyperagency that will have negative consequences for humanity as a whole. Hyperagency not only disrupts our sense of reverence before mystery and depth but also threatens our sense of morality in relating to the world. If continued, practices in hyperagency such as genetic enhancement will lead us to lose our sense of humanity altogether
Thesis (BA) — Boston College, 2018
Submitted to: Boston College. College of Arts and Sciences
Discipline: Departmental Honors
Discipline: Philosophy
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Adie, Steven G. "Enhancement of contrast in optical coherence tomography : new modes, methods and technology." University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0127.
Повний текст джерелаАнотація:
This thesis is concerned with exploiting the native optical coherence tomography (OCT) contrast mechanism in new ways and with a new contrast mechanism, in both cases to enhance the information content of the tomographic image. Through experiments in microsphere solutions, we show that static speckle contains information about local particle density when the effective number of scatterers in the OCT resolution volume is less than about five. This potentially provides contrast enhancement in OCT images based on local scatterer density, and we discuss the experimental conditions suited to utilising this in biological tissue. We also describe the corrupting effects of multiple scattering, a ubiquitous phenomenon in OCT, on the information content of the static speckle. Consequently, we detail the development of polarisation-based metrics for characterising multiple scattering in OCT images of solid biological tissues. We exploit a detection scheme used for polarisation-sensitive contrast for a new purpose. We present experiments demonstrating the behaviour of these metrics in liquid phantoms, and in biological tissues, ranging from homogeneous non-birefringent to highly heterogeneous and birefringent samples. We discuss the conditions under which these metrics could be used to characterise the relative contribution of single and multiple scattering and, thus, aid in the study of penetration depth limits in OCT. We present a study of a new contrast mechanism - dynamic elastography which seeks to determine the dynamic mechanical properties of tissues. We present a framework for describing the OCT signal in samples undergoing vibrations, and perform experiments at vibration frequencies in the order of tens to hundreds of Hertz, to confirm the theory, and demonstrate the modes of measurement possible with this technique. These modes of measurement, including acoustic amplitude-sweep and frequency-sweep, could provide new information about the local mechanical properties of a sample. We describe a technological advancement enabling, in principle, measurements of local tissue refractive index contrast much deeper within a sample, than is possible with conventional OCT imaging. The design is based on measurement of the optical path length through tissue filling a fixed-width channel situated at the tip of a needle. The needle design and calibration is presented, as well as measurements of scattering phantoms and various biological tissues. This design potentially enables the use of refractive index-based contrast enhancement in the guidance of breast biopsy procedures.
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Pastor, Alberto Claudio Miano. "Description of grains hydration kinetics and its enhancement using the ultrasound technology." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-05012016-164029/.
Повний текст джерелаАнотація:
The present work had as objective to study the hydration process of grains and its possible enhancement using the ultrasound technology. For that, it was studied the hydration kinetics of different grains (Andean lupin, Adzuki beans, sorghum grains and corn kernels) correlating the morphology with mathematical models and the mass transfer mechanisms. Moreover, the effect of the soaking water temperature and the grain initial moisture content were studied to complement the description of this process. The ultrasound application was studied for improving the hydration process, describing the possible mechanisms (direct and indirect effects) that improve the mass transfer process. Therefore, it was established the way by how water enters in the studied grains, demonstrating that the water transfer into the grains is a complex phenomenon and takes place not only due to diffusional mechanisms, but also by capillarity. In addition, suitable mathematical models were proposed and used to explain the processes, describing their parameters according to the grains morphology and the mass transfer mechanisms. Further, it was determined how ultrasound enhances the mass transfer and in which conditions the direct (inertial flow and sponge effect) and the indirect effects (micro channels formation by acoustic cavitation) take place in the process, maximizing the effect of this technology. Finally, it was demonstrated that the ultrasound technology enhanced the hydration process for corn kernels, reducing significantly the process time in approximately 35 %, without modifying the thermal, structural and rheological properties of their starch. In conclusion, the present work improved the description of the grain hydration phenomenon and proved that the ultrasound technology can be used to enhance this process without changing its main industrial component. It is highlighted that the obtained results are thus high desirable for both the industrial and academic point of view.O presente trabalho teve como objetivo estudar o processo de hidratação de grãos e sua possível melhora usando a tecnologia do ultrassom. Estudou-se a cinética de hidratação de diferentes grãos (tremoço andino, feijão Adzuki, grãos de sorgo e grãos de milho) correlacionando a morfologia com modelos matemáticos e os mecanismos de transferência de massa. Também foi estudado o efeito da temperatura e o conteúdo de umidade inicial do grão para complementar a descrição deste processo. Estudou-se a aplicação do ultrassom no processo de hidratação descrevendo-se os possíveis mecanismos (efeito diretos e indiretos) que melhoram a transferência de massa. Como resultado, foi estabelecida a forma como a água entra nos grãos estudados, demostrando que a transferência de água dentro dos grãos é um fenômeno complexo e que acontece por difusão e capilaridade. Foram propostos e utilizados modelos matemáticos apropriados para explicar os processos, descrevendo os parâmetros de acordo com a morfologia dos grãos e os mecanismos de transferência de massa. Ainda, determinou-se como o ultrassom melhora a transferência de massa e em que condições do processo acontecem os efeitos diretos (fluxo inercial e efeito esponja) e efeitos indiretos (formação de micro canais pela cavitação acústica), maximizando o efeito dessa tecnologia. Finalmente, demonstrou-se que a tecnologia do ultrassom melhora o processo de hidratação de grãos de milho, diminuindo significativamente o tempo do processo em cerca de 35 % sem alterar as propriedades térmicas, reológicas e estruturais do seu amido. Como conclusão, o presente trabalho melhorou a descrição de como os grãos são hidratados, demonstrando que o ultrassom pode ser usado para melhorar o processo de hidratação de grãos sem alterar os seus principais produtos industriais. Ressalta-se que os resultados obtidos são desejáveis tanto do ponto de vista acadêmico quanto industrial.
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Haug, Knut Hallvard Sverre. "Engineering humans : cultural history of the science and technology of human enhancement." Thesis, Birkbeck (University of London), 2016. http://bbktheses.da.ulcc.ac.uk/210/.
Повний текст джерелаАнотація:
This thesis investigates the technological imaginary of human enhancement: how it has been conceived historically and the scientific understanding that has shaped it. Human enhancement technologies have been prominent in popular culture narratives for a long time, but in the past twenty years they have moved out of science fiction to being an issue for serious discussion, in academic disciplines, political debate and the mass media. Even so, the bioethical debate on enhancement, whether it is pharmacological means of improving cognition and morality or genetic engineering to create smarter people or other possibilities, is consistently centred on technologies that do not yet exist. The investigation is divided into three main areas: a chapter on eugenics, two chapters on cybernetics and the cyborg, and two chapters on transhumanism. All three areas of enhancement thinking have a corresponding understanding of and reference to evolutionary theory and the human as a category. Insofar as ‘enhancement’ is a vague and relative turn, the chapters show how each approach wrestles with how to formulate what is good and desirable. When this has inevitably proven difficult, the technologies themselves dictate what and how ‘enhancement’ comes about. Eugenics treats the human in terms of populations – as a species, but also in abstract categories such as nation and race. I follow the establishment of eugenics from the development of a statistical understanding of measuring human aptitude, with emphasis on the work of Francis Galton and the formulation of the regression to the mean. The following two chapters on cybernetics and the cyborg analyses how the metaphor of the body as machine has changed relative to what is meant by ‘machine’: associated with Cartesian dualism, cybernetics marked a shift in how we understand the term. Through a reading of the original formulation of the cyborg, I connect it to evolutionary adaptationism and a cybernetic ‘black box’ approach. The last two chapters look at a more recent approach to enhancement as a moral imperative, transhumanism. Since some transhumanists seek to ground themselves philosophically as the inheritors to Enlightenment humanism, the concept of ‘morphological freedom’ is central, representing an extension of humanistic principles of liberty brought into an age which privileges information over matter. The final chapter looks at how the privileging of information leads to a universal computational ontology, and I specifically look at the work of Ray Kurzweil, a prominent transhumanist, and how the computationalist narrative creates a teleological understanding of both human worth and evolution.
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Oh, Jay J. "The Imago Dei and its implications for germ-line genetic enhancement technology." Theological Research Exchange Network (TREN), 1997. http://www.tren.com.
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Kerns, David L., and Glenn C. Wright. "Insecticidal and Yield Enhancement Qualities of Surround Particle Film Technology in Citrus." College of Agriculture, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/226092.
Повний текст джерелаАнотація:
Surround WP was evaluated at various spray volumes to determine if volumes lower than the label recommended volume of 250 gallon per acre would provide equivalent citrus thrips control and yield enhancement potential. All the spray volumes evaluated (50, 100, 150, and 250 gpa) appeared to be equally effective. It appears that as long as the spray coverage appears to be visually adequate, then coverage is sufficient. Application of Surround WP led to some increase in fruit size, particularly for the first harvest.
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Sorensen, Meghan Marie. "Student Attitudes toward Social Media Technology as an Enhancement to Language Acquisition." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3783.
Повний текст джерелаАнотація:
Language students today have grown up with a plethora of technology tools at their fingertips, which has in some cases earned them the title of "digital native". 'Students' high use of technology outside the classroom has led teachers and researchers to believe that technology could be highly effective for language learners when used appropriately. Yet little is known about how students actually react to technology-based tools for language learning purposes. This study seeks to not only understand student attitudes toward technology in general, but also to see how those attitudes might affect student attitudes toward online language learning tools in a social media context. Using a design-based research approach, we implemented a curriculum that utilizes a social networking environment in which students could consume authentic language samples and practice using the language in a controlled environment. Through the analysis of pre and post surveys, it was discovered that age was the most significant predictor of student attitudes toward technology, but that the extent to which students use technology proves to be a more significant predictor when other variables are factored in. Furthermore, it was discovered that general attitudes toward technology do affect the ways in which students will react to a technology-based curriculum. Nevertheless, the way in which a curriculum is presented can be a stronger factor in predicting how the curriculum will be received.
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Al-Atta, Ammar Jaber. "Supercritical water oxidation of hazardous waste : process enhancement and reactor design." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/53356/.
Повний текст джерелаАнотація:
The work presented in this thesis is focused on two specific areas of supercritical water oxidation (SCWO). Firstly, the design and testing of an innovative anticorrosive reactor design that can be used for the SCWO of hazardous organic waste. Secondly, exploiting the merits of counter current mixing reactor in combining two processes; Supercritical water oxidation (SCWO) and supercritical water hydrothermal synthesis (SCWHS) in one reactor. In Chapter 1, an introduction to supercritical fluid and supercritical water oxidation is given, followed by a brief account of the main problems associated with SCWO. This includes a review of the experience to date, with different reactor designs for corrosion control. This Chapter also provide an introduction to hydrothermal methodology and continuous flow reactor design for nanoparticle production, along with the aims and objective of this PhD. Chapter 2 details the components and construction of the experimental rigs used in this thesis. Additionally, this Chapter presents the principles behind the main analytical techniques used throughout this work, along with the definition of some important parameters. Chapter 3 reports the use of a physical modelling approach to assess mixingdynamics inside three different types of reactor where supercritical water is mixed with a second colder, waste containing, effluent flow. Physical or `pseudo'modelling was used to simulate the general flow patterns and mixing regimes in transparent pseudo reactors (to allow visualization). Towns water was used to simulate the supercritical water flow and 40% w/w aqueous sucrose solution to simulate the cold aqueous effluent flow. This visual technique allowed the quantification of mixing efficiency, as well as identification of issues such as flow recycling, stagnant zones, and other inconsistencies in the mixing dynamics. An upwards co-current protected wall reactor arrangement provided the `best' mixing i.e. with minimal wall contact during the downstream oxidation process. A combined process of SCWO and SCWHS in a continuous counter current reactor is the focus of Chapter 4. Acrylic acid was chosen as a model compound to represent an organic wastewater and the effects of the reaction temperature, residence time, oxidant ratio and acrylic acid concentration on chemical oxygen demand (COD) were all investigated. Two different experimental configurations for oxidant delivery were carried out in `pre-heated' and `non-preheated' oxidant configurations. With a stoichiometric excess of 100% oxygen, COD reduction levels of 80% (non-preheated) and 15% (preheated) were achieved with very short residence times. SCWHS was achieved through the addition of small amounts of various soluble metal salts in the cold up flow resulted in nanoparticles forming which increased the reaction rate and hydrothermal oxidation efficiency. The addition of small amounts of chromium nitrate (>5mM) results in nearly 100% COD reduction at 380C and residence times of 0.75 seconds. The potential economic benefits of combining the two processes together, in the different configurations, were also evaluated. In Chapter 5, The results of the catalytic oxidation in supercritical water of a non-biodegradable and highly toxic organic compound (phenol) are presented. The reactions were studied in a continuous counter current reactor through the in-situ formation of Fe2O3 catalyst. The preliminary results showed that catalytic non-preheated oxidant configuration resulted in increased COD removal when compared to other oxidant delivery methods. It was shown that temperatures below 400C could be used to decompose these compounds into final product and that complete conversion of COD could likely be expected within less than 1 second. It was demonstrated that SCWO combined with SCWHS is a feasible and cost-effective alternative for the destruction of contaminants in water. In Chapter 6, A laboratory-scale protected wall reactor rig was designed, constructed, tested, and operated to validate the pseudo modelling for application to SCWO. SEM, SEM/EDS, and XRD results showed that 1 meter long protected wall reactor was divided into two regions. 25% of the reactor length was protected by the flow of clean supercritical water. Near complete removal of the organic content of 2,4-DCP was obtained at mild operating conditions. To conclude, a summary of the work detailed in this thesis is delivered in Chapter 7. The most pertinent findings from this work are put forward, followed by a discussion of future work which could lead on from this thesis.
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Peng, Xiaodong. "Liquid air energy storage : process optimization and performance enhancement." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8615/.
Повний текст джерелаАнотація:
Liquid Air Energy Storage (LAES) aims to large scale operations a~d-:_has caught the attention due to the advantages of high energy density, a highly competitive capital cost, no geographical constraints and environmental friendliness. However, the situation is getting more challenging due to its disappointed performance in the current configuration. This thesis focuses increase the system performance of the LAES technology, particularly through developing novel thermodynamic cycles for an increased use of the thermal energy and system optimization strategies. The improvements to the LAES mainly aim at two points: increasing power output by using compression heat and rising the liquification rate through external cold sources. To effectively use the heat, three integrated LAES systems with the Organic Rankine Cycle (ORC) are proposed, termed LAES-ORC-VCRC system, LAES-ORC-ARC system and LAES-ORC system respectively according to different cooling methods. External cold sources, such as Liquefied Natural Gas (LNG), can be used to enhance air liquefication, and hence two integrated LAES systems, termed the LAES-LNG and the LAES-LNG-CS, are investigated and optimized.
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Wen-Fwu, Tsai Filip. "Single Channel Spectrum-based Speech Enhancement Using Neural Networks." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254410.
Повний текст джерелаАнотація:
The ability to communicate is fundamental to form a relationship, and it is anecessity for a well-functioning society. Since a major part of our daily communicationtakes place orally, the ability to perceive speech is important. However,it is not always as easy to perceive the message, especially when the level of backgroundnoise partially masks the speech. For a person with hearing impairment,the situation gets even worse.The impact of background noise is also challenging other domains, and one ofthose is regarding virtual assistants, which have recently become more commondue to the technological advancements. Since virtual assistants have allowedus to interact with our technological devices in our daily lives, the dependencythat they work becomes more critical. This dependency especially holds whenwe are required to interact with them by speech. Still, in both suggested cases,background noise remains an issue to some degree. Hence, the possibility toreduce the noise influence is likely to have a significant role in how our societydevelops.In this report, we evaluate the possibility of reducing background noise.To do it, we proposed a new neural network architecture which is based on theprinciples of extreme learning machine. Considering that this report works withspectrum-based speech, appropriate constraints to ensure non-negativity in ouroptimization problem has been carried out. Moreover, different configurationsapplied to the architecture have been observed, which includes unprocessed vs.pre-processed features, masking filter, and stacking several single architecturelayers.The results show that the proposed architecture with the unprocessed, noisyspeech, input performs better than an input pre-processed by a well-knownmethod. Another finding observed was that relaxation in constraint yieldedbetter performance of a noisy speech than based on a non-negative convexconstrainedsolution.Att kunna kommunicera är fundamentalt för att forma relationer och är däraven nödvändighet för att få till ett fungerande samhälle. Eftersom en betydande del av den dagliga kommunikationen sker muntligt blir betydelsen av att kunna uppfatta vad som sägs betydelsefullt. Att kunna uppfatta vad som sägs är dock inte alltid helt enkelt, framförallt när ljudnivån av bakgrundsstim delvis maskerar talet. Desto svårare blir det för människor som har någon form av hörselskada.Effekterna av bakgrundsbrus framför även utmaningar inom andra områden. Ett av dessa områden är gällande virtuella assistenter, som blivit allt vanligare på grund av de tekniska framstegen. I och med att virtuella assistenter har möjliggjort möjligheten att för oss interagera med våra tekniska apparater, blir det allt viktigare att de fungerar. Detta gäller framför allt i de situationer där vi dessutom krävs att kommunicera muntligt med en virtuell assistent. Frågan som kvarstår är hur bakgrundsstim ska reduceras då bakgrundsstim i de båda ovannämnda fallen försvårar förståelseförmågan i olika omfattningar. Med detta sagt antyds möjligheten att kunna reducera bakgrundsstim ha stor betydelse för hur samhället kommer att utvecklas.I denna rapport kommer vi att utvärdera möjligheten att reducera bakgrundsstim. För att uppnå detta kommer vi att framföra en ny artificiella neurala nät arkitektur baserade utifrån id´eer från extrem inlärande maskin (eng. extreme learning machine). I och med att bearbetning sker på spektrumbaserat tal kommer lämpliga bivillkor appliceras för att garantera icke-negativ utsignal vid formulering av optimeringsproblem som har tagits fram. Vidare har olika sammansättningar undersökts, vilket inkluderar förarbetat kontra ickeförarbetat spektrum som insignal, filtrering och sammankoppling av flera lager av en viss arkitektur.Utifrån de erhållna resultaten visar det sig att den förslagna arkitekturen med insignal av ett icke-förarbetat brusigt tal presterar bättre än när insignalenär förädlad genom en välkänd metod inom detta område. Ett annat fynd som också har observerats är att lättnad i bivillkor resulterade till förbättring av ettbrusigt tal än när bivillkoret grundar sig i en icke-negativ konvex lösning.
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Hall, Stephen Thomas. "Enhancement of magnetic susceptibility by leaching and application in mineral separation." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=71807.
Повний текст джерелаАнотація:
Enhancement of the magnetic susceptibility of pyrite particles is observed following a mild oxidative pressure leach. This increase is studied for a range of experimental conditions. The increase in susceptibility is attributed to the formation of a thin layer of ferromagnetic oxides. This layer of leach reaction products has been extensively studied using various analytical techniques. The species identified are (gamma)-Fe(,2)O(,3) and Fe(,3)O(,4), which supports a previously postulated reaction model.This leach treatment significantly increases the magnetic susceptibility of coal-pyrite permitting improved high-gradient magnetic desulfurization of a high pyritic sulfur coal.
The leach treatment also enhances the magnetic susceptibility of other iron-containing mineral sulfides. However, application of this leach pretreatment in sulfide/sulfide separations is limited due to galvanic coupling effects which passivate the susceptibility increase reaction. In the presence of oxides, coal and probably other non-sulfides passivation does not occur and the susceptibility of the iron-bearing sulfide increases. The potential exists for the application of the leach as a pretreatment in enhancing fine iron-containing sulfide/non-sulfide magnetic separations.
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Lee, Deok-Hyung (Doug). "Mechanisms of surface hardness enhancement in ion-implanted amorphous carbon." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/19639.
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Wang, Ruonan. "Enhancement/depletion-mode HEMT technology for III-nitride mixed-signal and RF applications /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?ECED%202008%20WANG.
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Cheng, Tik-sang Steve, and 鄭滌生. "Information technology for service enhancement in shopping mall: a case study of MegaBox." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B42905436.
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Dissanayake, Mevan C. "Evaluation of IMETTM Technology for Enhancement of Wastewater Sludge Digestion." Youngstown State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1403531914.
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Cheng, Tik-sang Steve. "Information technology for service enhancement in shopping mall a case study of MegaBox /." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B42905436.
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Karelid, Mikael. "Image Enhancement over a Sequence of Images." Thesis, Linköping University, Department of Electrical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-12523.
Повний текст джерелаАнотація:
This Master Thesis has been conducted at the National Laboratory of Forensic Science (SKL) in Linköping. When images that are to be analyzed at SKL, presenting an interesting object, are of bad quality there may be a need to enhance them. If several images with the object are available, the total amount of information can be used in order to estimate one single enhanced image. A program to do this has been developed by studying methods for image registration and high resolution image estimation. Tests of important parts of the procedure have been conducted. The final results are satisfying and the key to a good high resolution image seems to be the precision of the image registration. Improvements of this part may lead to even better results. More suggestions for further improvementshave been proposed.
Detta examensarbete har utförts på uppdrag av Statens Kriminaltekniska Laboratorium (SKL) i Linköping. Då bilder av ett intressant objekt som ska analyseras på SKL ibland är av dålig kvalitet finns det behov av att förbättra dessa. Om ett flertal bilder på objektet finns tillgängliga kan den totala informationen fråndessa användas för att skatta en enda förbättrad bild. Ett program för att göra detta har utvecklats genom studier av metoder för bildregistrering och skapande av högupplöst bild. Tester av viktiga delar i proceduren har genomförts. De slutgiltiga resultaten är goda och nyckeln till en bra högupplöst bild verkar ligga i precisionen för bildregistreringen. Genom att förbättra denna del kan troligtvis ännu bättre resultat fås. Även andra förslag till förbättringar har lagts fram.
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Hassan, Faiza. "Heterogeneous catalysis in supercritical fluids : the enhancement of catalytic stability to coking." Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/3166/.
Повний текст джерелаАнотація:
Catalytic deactivation caused by coking was studied in ZSM5 and zeolite Y catalysts during the isomerisation of 1-hexene under sub and supercritical conditions. The effects of varying temperature and pressure, from 220–250 °C and 10-70 bar respectively, on conversion and coke deposition were studied in both zeolites. TGA, DRIFTS, nitrogen sorption isotherms for fresh and coked catalysts and catalyst acidity measurements were compared. In ZSM5 the catalyst was stable for 96 hours. TGA and DRIFTS results show coke deposits were mainly polyolefinic and the amount decreases considerably from 18.8 wt% in the subcritical region to 10 wt% in the supercritical region. In zeolite Y, decay in conversion was observed with the rate of deactivation being slower at supercritical conditions at 235 °C and 40 bar. Naphthalene hydrogenation on NiMo/γ-Al2O3 catalyst was also studied. The effect of temperature, pressure, varying naphthalene feed concentration and operating in sub and supercritical conditions were studied. Coke deposit decreased by 38 wt% in the supercritical region. SC CO2 (Tc 31.04 °C, Pc 73.8 bar) was also used to re-activate the coked catalysts. This resulted in recovering 93% of the catalytic activity and 37% of the coke was effectively extracted by SC CO2.
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Sunnegårdh, Johan. "Iterative Enhancement of Non-Exact Reconstruction in Cone Beam CT." Thesis, Computer Vision, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2577.
Повний текст джерелаАнотація:
Contemporary algorithms employed for reconstruction of 3D volumes from helical cone beam projections are so called non-exact algorithms. This means that the reconstructed volumes will contain artifacts irrespective of the detector resolution and number of projections angles employed in the process.
It has been proposed that these artifacts can be suppressed using an iterative scheme which comprises computation of projections from the already reconstructed volume as well as the non-exact reconstruction itself.
The purpose of the present work is to examine if the iterative scheme can be applied to the non-exact reconstruction method PI-original in order to improve the reconstruction result. An important part in this implementation is a careful design of the projection operator, as a poorly designed projection operator may result in aliasing and/or other artifacts in the reconstruction result. Since the projection data is truncated, special care must be taken along the boundaries of the detector. Three different ways of handling this interpolation problem is proposed and examined.
The results show that artifacts caused by the PI-original method can indeed be reduced by the iterative scheme. However, each iteration requires at least three times more processing time than the initial reconstruction, which may call for certain compromises, smartness and/or parallelization in the innermost loops. Furthermore, at higher cone angles certain types of artifacts seem to grow by each iteration instead of being suppressed.
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Palm, Niklas. "Enhancement of short-term forecasts : A study of a pharmaceutical distributor." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-62437.
Повний текст джерелаАнотація:
Forecasts are used to predict the uncertain outcome of a variable. These predictions are made to get an understanding of likely future scenarios which allows planning in advance. Forecasts are commonly used in inventory control systems to estimate the future demand. This estimation along with the estimated precision of the forecast can be used to determine adequate safety stocks. In extension, forecasts of the future demand can be used to support decisions regarding the replenishment of inventories. This thesis involves forecasting of the demand of pharmaceutical drugs. In particular, drugs that are referred to as generics. The demand of generics can fluctuate heavily due to the substitution system and can therefore be troublesome to forecast. The main objective of this thesis is to design a suitable forecast approach for the demand of generics, and to examine how these forecasts can be used to control the replenishment of inventories. The project was executed at a pharmaceutical drug distributor and hopes to enlighten some new techniques that can be used to improve the handling of generics. To achieve the objective of this thesis, the initial focus was on the current state. The currently used methods where studied and compared with theories and methods described in literature. Assumptions and theories on which the currently used methods are based on could thus be identified. These assumptions where later assessed as either reasonable or unreasonable. Finally, a new forecast approach was designed to account for the insights gained from evaluating the current methods. The result of this thesis is a forecast approach suitable to forecast the demand of generics that account for the fluctuation in demand which occurs due to the substitution system. It assumes that the demand has a constant demand model, but an alternative method suitable for the trend model is also given. It is proposed that tracking signals are used to monitor the forecast such that systematic errors are identified. Furthermore, the literature review indicates that alternatives to the current method used to determine the reorder point should be considered for occasionally demanded generics.
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McCormick, Sean Eli. "Transcendence: An Ethical Analysis of Enhancement Technologies." Cleveland State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=csu1464233924.
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Morgan, Fearghal John. "A investigation of the manufacture and characterisation of enhancement-type buried channel M.O.S. transistors." Thesis, Queen's University Belfast, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254322.
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Alsoqyani, Faihan Saleh. "Supercritical water oxidation of nitrogen-containing organic compounds : process enhancement using isopropyl alcohol." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7296/.
Повний текст джерелаАнотація:
The research in this thesis aimed to study efficiency and viability of supercritical water oxidation (SCWO) technology in treating diluted N,N-dimethylformamide (DMF), 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and ammonia containing model wastewaters that were selected due to their hazard, wide usage in industry and having different degrees of refractoriness. A lab-scale SCWO tubular reactor was operated to obtain necessary data to investigate the destruction of selected compounds at certain operating conditions in addition to studying the oxidation kinetics of DMF and DBU. Also, Isopropyl Alcohol was used to enhance the destruction of treating DMF, DBU and ammonia. Results showed that temperature was the most influential variable where near complete TOC removal was obtained during DMF and DBU oxidation at 525oC and 250 bars. Temperatures of 400-550oC were not enough to achieve a significant destruction for ammonia. Organic concentrations and oxidant ratios also showed positive effects on the destruction of DMF, DBU and ammonia. IPA showed an essential role to destroy DMF, DBU and ammonia when used where a TOC removal of 99.4% and 99.2% was achieved for DMF and DBU respectively at 525oC and 250 bars and maximum TN removal of 97% was obtained at 550oC and 250 bars during ammonia oxidation. Also the presence of IPA reduced the activation energy of treated compounds where the values were 21.9 and 25.7 kJ/mol for DMF and DBU, respectively. Also it was found that oxygen has an influence and with oxygen order of 0.38 and 0.32 for DMF and DBU respectively.
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Cofino, Jonathan M., and Armando Barreto. "Using Sonic Enhancement to Augment Non-Visual Tabular Navigation." FIU Digital Commons, 2014. http://digitalcommons.fiu.edu/etd/1570.
Повний текст джерелаАнотація:
More information is now readily available to computer users than at any time in human history; however, much of this information is often inaccessible to people with blindness or low-vision, for whom information must be presented non-visually. Currently, screen readers are able to verbalize on-screen text using text-to-speech (TTS) synthesis; however, much of this vocalization is inadequate for browsing the Internet. An auditory interface that incorporates auditory-spatial orientation was created and tested. For information that can be structured as a two-dimensional table, links can be semantically grouped as cells in a row within an auditory table, which provides a consistent structure for auditory navigation. An auditory display prototype was tested.
Sixteen legally blind subjects participated in this research study. Results demonstrated that stereo panning was an effective technique for audio-spatially orienting non-visual navigation in a five-row, six-column HTML table as compared to a centered, stationary synthesized voice. These results were based on measuring the time- to-target (TTT), or the amount of time elapsed from the first prompting to the selection of each tabular link. Preliminary analysis of the TTT values recorded during the experiment showed that the populations did not conform to the ANOVA requirements of normality and equality of variances. Therefore, the data were transformed
using the natural logarithm. The repeated-measures two-factor ANOVA results show that the logarithmically-transformed TTTs were significantly affected by the tonal variation method, F(1,15) = 6.194, p= 0.025. Similarly, the results show that the logarithmically transformed TTTs were marginally affected by the stereo spatialization method, F(1,15) = 4.240, p=0.057. The results show that the logarithmically transformed TTTs were not significantly affected by the interaction of both methods, F(1,15) = 1.381, p=0.258. These results suggest that some confusion may be caused in the subject when employing both of these methods simultaneously. The significant effect of tonal variation indicates that the effect is actually increasing the average TTT. In other words, the presence of preceding tones increases task completion time on average. The marginally-significant effect of stereo spatialization decreases the average log(TTT) from 2.405 to 2.264.
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Van, Niekerk Elizabeth Catharina. "In vitro antimalarial efficacy enhancement of selected antibiotics with PheroidTM technology / E.C. van Niekerk." Thesis, North-West University, 2010. http://hdl.handle.net/10394/4999.
Повний текст джерелаАнотація:
The Plasmodium falciparum parasite, carried by Anopheles mosquitoes, is currently a global problem due to the rising incidence of resistance of the parasite to available antimalaria drugs. Resistance and difficult treatment groups, including pregnant woman and young children, are pressing for the development of new, safe and effective prophylactic and treatment antimalarials. Because of the extensive process of developing new drugs, researchers and health care professionals have turned to combination therapy where a fast acting antimalarial is combined with slower acting drugs, such as antibiotics.
The macrolide antibiotics, erytbromycin and azithromycin, have been studied to a limited extent for their potential antimalarial effect. Certain advantages, such as their safety profile (especially that of azithromycin) in pregnancy and administration to young children, motivates continual research into the advancement of the effect these drugs exude on malaria. Drug delivery systems contribute to the efficacy of medicines, conquering several difficulties of treatment with oral medication. Pheroid™ technology is a patented drug delivery system, mainly consisting of plant and essential fatty acids, and has been demonstrated to entrap, carry and deliver pharmacologically active compounds and other useful molecules.
This study compared the in vitro effects of the macrolide antibiotics on the growth of a chloroquine-resistant strain (RSA 11) of Plasmodium falciparum to the effects of the macrolides entrapped in Pheroid™ vesicles on the same strain over and extended observation period of 144 hours. ELISA assays were conducted by analysing the HRP II (histidine-rich protein) levels on a pre-coated microtitre plate. The effects of the type of formulation, concentration and time were compared.
The in vitro difference between erythromycin alone and entrapped in Pheroid™ vesicles were found to be statistically significant (p = 0.000000) while the effects of both formulations did not seem to be concentration dependant (p = 0.628424). Prolonged exposure was also statistically meaningful (p = 0.008268), though it seems that exposure need not exceed 96 hours. The type of formulation, in the case of azithromycin (azithromycin alone vs. azitbromycin entrapped in Pheroid™ vesicles), proved statistically significant (P = 0.002572), while neither formulation seemed concentration dependant (P = 0.427731). Prolonged exposure was found to be statistically insignificant for azithromycin (P = 0.221941).Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2010.
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Jebari, Karim. "Human enhancement and technological uncertainty : Essays on the promise and peril of emerging technology." Doctoral thesis, KTH, Filosofi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-156724.
Повний текст джерелаАнотація:
Essay I explores brain machine interface (BMI) technologies. These make direct communication between the brain and a machine possible by means of electrical stimuli. This essay reviews the existing and emerging technologies in this field and offers an inquiry into the ethical problems that are likely to emerge. Essay II, co-written with professor Sven-Ove Hansson, presents a novel procedure to engage the public in deliberations on the potential impacts of technology. This procedure, convergence seminar, is a form of scenario-based discussion that is founded on the idea of hypothetical retrospection. The theoretical background and the results of the five seminars are presented. Essay III discusses moral bioenhancement, an instance of human enhancement that alters a person’s dispositions, emotions or behavior. Moral bioenhancement could be carried out in three different ways. The first strategy is behavioral enhancement. The second strategy, favored by prominent defenders of moral enhancement, is emotional enhancement. The third strategy is the enhancement of moral dispositions, such as empathy and inequity aversion. I argue that we ought to implement a combination of the second and third strategies. Essay IV considers the possibility and potential desirability of sensory enhancement. It is proposed that existing sensory modalities in vertebrate animals are proof of concept of what is biologically possible to create in humans. Three considerations on the normative aspects of sensory enhancement are also presented in this essay. Essay V rejects disease prioritarianism, the idea that the healthcare system ought to prioritize the treatment of diseases. Instead, an approach that focuses on what medicine can accomplish is proposed. Essay VI argues that from the idea that species have an intrinsic value and that humanity has a collective responsibility to protect animal species from extinction, the conclusion that we ought to recreate species follows. Essay VII argues that unknown existential risks have not been properly addressed. It proposes a heuristic for doing so, and a concrete strategy. This strategy consists in building refuges that could withstand a large number of catastrophic events.QC 20141204
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Hussain, Atif. "Enhancement of hygrothermal properties of bio-based thermal insulation materials via sol-gel technology." Thesis, University of Bath, 2018. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.767569.
Повний текст джерелаАнотація:
This study involves the modification of a bio-based aggregate, hemp shiv, using functionalised silica-based coatings. This is the first time sol-gel technology is used in the treatment of hemp shiv to develop sustainable thermal insulation building materials with enhanced hygrothermal properties. Bio-based materials such as hemp shiv have a tendency to absorb large amounts of water due to their hydrophilic nature and highly porous structure. In contrast, the high porosity of hemp shiv provides excellent moisture buffering and thermal insulating properties. In this work, the hydrophilicity of the hemp shiv was reduced without compromising its moisture buffering ability. A detailed investigation into the physical and chemical properties, surface roughness, porosity and microstructure of hemp shiv is presented. Application of coatings on hemp shiv was found to alter the properties of hemp shiv. The focus of this work was to particularly enhance the water-resistance of hemp shiv without significantly altering the morphology and microstructure of hemp shiv. The coatings were formulated by the cohydrolysis and polycondensation of tetraethoxyorthosilicate (TEOS). The effect of methytriethoxysilane (MTES) and hexadecyltrimethoxysilane (HDTMS) as functionalising agents in the coating was evaluated. The impact of precursors and their concentration in the coating formulation showed varying results on the hydrophobicity and roughness of hemp shiv. Furthermore, the porosity of hemp shiv was affected by the number of coating layers thereby blocking the pores responsible for the moisture buffering behaviour of hemp shiv. The selected coating formulation was found to increase the hydrophobicity of hemp shiv providing water contact angles up to 118° and reducing the water absorption rates by 250% without showing a significant reduction in the moisture absorption capacity. Novel thermal insulation building composites were developed using the coated hemp shiv in both a silica and a starch-based matrix. The composites were characterised for their hygrothermal, physical and mechanical properties where it was found that the sol-gel coating reduced water absorption capacity without affecting the moisture buffering ability of the composites. The newly designed light weight high performance composites have potential as sustainable thermal insulators and can establish innovative concepts for global application.
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Yi, Congwen. "Reliability study of enhancement-mode AIGaN/GaN HEMT fabricated with fluorine plasma treatment technology /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?ECED%202008%20YI.
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Gamble, Maria. "Digital enhancement of senior secondary dance assessment." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2021. https://ro.ecu.edu.au/theses/2426.
Повний текст джерелаАнотація:
This research examined the use and effects of digital technology in supporting and enhancing practical high stakes assessments in a senior secondary dance course in Western Australia (WA). The participants comprised twenty students from one school who were enrolled in ATAR Dance for 2016/17 and ten WA secondary dance education experts. A mixed method embedded design allowed for the analysis of both qualitative and quantitative results to gain perspective and understanding of using digital technology to facilitate the current Western Australia Certificate of Education (WACE)/Australia Tertiary Admissions Rank (ATAR) dance examination as well as the preparation for it and marking of it. An existing assessment application prototype from Edith Cowan University was used and further developed into the dance assessment application (the DAapp) in the study.
Student participants were asked to perform their usual school based practical dance assessment, whilst the markers were asked to assess the performances in either live (traditional format of examination) or digital (using the application to view the captured performances) contexts. An alternate interview was also administered to the students as part of a workshop where they (and their classroom teacher) explored the ways in which the technology might be used to support the examination, the preparation for it and marking of it. The study was enriched by a survey and focus group interviews.
Amongst the participants was a shared desire to use technology where possible to support and enhance learning as well as increase a shared understanding of the assessment challenges. While the teachers and markers were bound by historical practices, viewpoints, and the dominant summative model, they were willing to explore new possibilities. Not only does this research contribute to an under researched area of assessment, it provides strategies to enhance the preparation of and enactment of assessment in dance performance.
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Williams, Stephannia P. "Hydroentanglement Process as a Finishing Treatment for the Enhancement of Knitted Fabrics." NCSU, 2006. http://www.lib.ncsu.edu/theses/available/etd-04072006-140923/.
Повний текст джерелаАнотація:
This research involves the application of hydroentangling technology as a means of significantly improving knitted fabric properties. In the past, various efforts have been made, directed at improving the dimensional stability and physical properties of woven and knitted fabrics through the finishing technique of hydroentanglement. In such applications, warp and filling fibers in fabrics are hydroentangled at crossover points to effect enhancement in fabric cover. The process parameters of hydroentangling are investigated and optimized to achieve desired results. Potential benefits include enhanced fabric durability, stability, and appearance.
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Sumair, Faisal Ahmed. "Preparation and characterisation of eutectic nanofluids for heat transfer enhancement in flat plate solar collectors." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/48390/.
Повний текст джерелаАнотація:
Use of thermal energy storage (TES) materials in solar collectors is known to be the most effective way of storing thermal energy. The most conventional and traditional heat storage element is water. However, due to low thermal conductivity (TC) in vapor state its applications as a heat storage medium are limited. An alternative option is to utilize organic and inorganic TES materials as they both operate at low and medium temperature ranges. Organic TES materials such as paraffins are non-corrosive and possess high latent heat capacity. On the contrary, inorganic TES materials possess high density and appreciable specific heat capacity (SHC). Due to rapid progress and advancement in nanotechnology, varieties of nanomaterials were dispersed in various base fluid(s) to enhance thermo-physical properties. Here the current status and future development trends of TES materials has been presented. Furthermore, an extensive research on enhancement of TC and SHC of various TES material doped with nanomaterials has been discussed. Enhancement in heat capacity (HC) and thermal conductivity (TC) with dispersion of graphene (GE) nanoparticles in low temperature molten salt was investigated. Three different nanoparticle concentrations (0.01, 0.05 and 0.1 wt. %) were dispersed in molten salt composed of 5.76% NaNO3, 21.36% KNO3, 24.84% Ca(NO3)2, 41.08% CsNO3 and LiNO3 7.44% by weight. Doping of GE resulted in enhanced HC ranging from 5-13%, whereas, TC showed enhancement up to 2.44%, with respect to GE concentration. Various theoretical models were tested to predict TC and HC of GE doped molten salt. Maxwell and Hamilton-Crosser TC models show good agreement with experimental results with deviation of ±3% while Nan’s TC model over predicted TC value. Conventional HC equation fits well with the experimental data with deviation < 14%. Thus, the results obtained show the potential of GE doped molten salt as thermal energy storage (TES) medium in various heat transfer applications. This work also investigates the rheological and corrosion properties of graphene (GE) dispersed in eutectic salts. It was observed that doping of GE has significantly enhanced the viscosity of base salt. This enhancement in GE dispersed eutectic salt is mainly due to the presence of solid GE sheets and its coagulation in eutectic salts. Various concentrations of GE and temperature ranges were studied here. Eutectic salt dispersed GE behaved as non-Newtonian fluid at 70, 80 and 90 oC except at 200 oC, where it behaved as a Newtonian fluid. Viscosity of nanosuspension was predicted using Einstein’s equation. Furthermore, corrosion studies using ASTM D130 method were performed to analyse the effects of base fluid on copper and stainless steel (SS304) at elevated temperatures. Fourier transform infrared spectrometer (FTIR) result shows that the presence of all nitrate bonds in synthesized base salt and GE dispersed base salt. X-ray diffraction depicts that the doping of GE in eutectic salt does not alter the crystal structure of nitrate molecules. EDX results confirm that both Cu and SS304 material were corroded. SS304 exhibited constant corrosion with an increase in GE concentration dispersed in eutectic salt, whereas copper exhibited an increase in corrosion rate with an increase in GE concentration. Kinetic studies have been carried out for molten salt and GE dispersed molten salt. It was concluded that dispersion of GE has not altered decomposition rate of nitrate of ions. In application, we have fabricated and tested two types of solar collectors, i.e., solar thermal collector and photo-voltaic/thermal collector for TES material. Test was carried out to confirm the thermal performance of both solar collectors under water, base salt and GE dispersed base salt as TES. Results proved that in both types of solar collectors, all three concentrations of GE (0.01, 0.05 and 0.1 wt. %) dispersed base salt were having high thermal performance than water and base salt. Thus, it was concluded that GE dispersed molten salt can be successfully used as TES material in both solar collectors.
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Lamine, Slim 1965. "A predictive model of shelf life enhancement for meat packed under modified atmospheres." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277920.
Повний текст джерелаАнотація:
A dynamic model of fresh beef packaged under modified atmospheres has been developed. This model links the change in meat color with the permeation of gases (O₂, CO₂, N₂) through the packaging film. Its viability is demonstrated with experimental data using muscle semimembranosus with which it was shown that color change of the meat surface and the change of headspace gas concentration were well described by the model. Moreover, the model parameters were obtained independently of the model itself through the literature. A major result of the model showed that surface color is independent of oxygen concentration above 5%. Moreover, under aseptic conditions and ambient atmosphere concentrations, shelf-life of muscle semimembranosus was shown to be 11 days with this value possibly being a minimum.
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McCloskey, Edward Daniel. "Q-Enhanced LC Resonators for Monolithic, Low-Loss Filters in Gallium Arsenide Technology." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/31959.
Повний текст джерелаАнотація:
The rapid development of wireless applications has created a demand for low-cost, compact, low-power hardware solutions. This demand has driven efforts to realize fully integrated, "single-chip" systems. While substantial progress had been made in the integration of many RF and baseband processing elements through the development of new technologies and refinements of existing technologies, progress in the area of fully monolithic filters has been limited due to the losses (low Qs) associated with integrated passive elements in standard IC processes.
The work in this thesis focuses on the development low-loss, Q-enhanced LC filters in GaAs E/D-SAGFET technology. This thesis presents a methodology for designing Q-enhanced LC resonators and low-loss, monolithic LC filters based on these resonators.
The first phase of this work focused on the Q-enhancement of LC resonator structures using FET-based active negative resistance circuits. Three passive resonators were designed, fabricated, and measured to determine their loss and frequency response. Furthermore, six Q-enhanced resonators were designed, fabricated, and measured to compare the performance of various negative resistance circuit designs.
In the second phase of this work, four of these Q-enhanced resonator designs were used to implement fully-integrated second-order Butterworth bandpass filters. Each filter was designed for a 60 MHz, -3 dB bandwidth centered at 1.88 GHz, corresponding to the North American PCS transmit band. The best filter design achieves 0 dB of passband insertion loss while consuming 16 mA of current from a 3 V source (48 mW). Passband gain (up to 15 dB) can be achieved with increased bias current before instability is encountered. The filter provides more than 30 dB of rejection at 1.7 and 2 GHz and more than 70 dB of rejection below 1.5 GHz. In the filter passband, the noise figure is 12 dB and the output 1 dB compression point is -18 dBm. These Q-enhanced LC filters have potential application as image-reject filters in GaAs integrated transceiver designs.Master of Science
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Jonsson, Åsa. "Enhancement of Dry Content in Coating Solution for Functional Packaging." Thesis, Linköping University, Department of Physics, Chemistry and Biology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-16576.
Повний текст джерелаАнотація:
The main goal for a packaging is to protect the product inside. Typical packaging nowadays is made of layers of paper and barriers consisting of plastics or aluminum foil. A problem with the barrier used today is the environmental thinking. Xylophane® is an environmental friendly and biodegradable alternative to the current barrier material used in packaging. It consists of the natural carbohydrate xylan and additives. Xylophane® is an efficient barrier to oxygen, grease and aroma and can prolong the shelf life of sensitive food.
The raw material xylan is water soluble and Xylophane® can be coated on paper, board and plastics without using other solvents. A problem with the drying process is the amount of energy needed and the consumption needs to be decreased. Also, the drying capacity of the equipment to be used is often limited and the amount of water to be dried off is critical for the success of the coating process. By increasing the dry content of Xylophane® without increasing the viscosity too much, the drying process can be more effective. In this thesis, studies were made of using a filler as an additive to increase the dry content without destroying the barrier properties.
With an experimental design, a suitable relationship between the ingredients xylan (X), plasticizer (P) and filler (F) was found. Xylan is the main component and is needed to get a good oxygen barrier. The plasticizer decreases the oxygen barrier properties but is needed to make the material more flexible. The filler is positive for the barrier properties. The chosen composition was X:P = 7:3 and X:F = 1:1. Some extra experiments were made to find a reasonable value of the dry content. Dry contents around 18 % work well with temperatures at and above 45°C, but to manage to perform coating at room temperature the dry content needs to be lower.
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Van, Huyssteen Este. "Efficacy enhancement of the antimalarial drugs, mefloquine and artesunate, with PheroidTM technology / E. van Huyssteen." Thesis, North-West University, 2010. http://hdl.handle.net/10394/5050.
Повний текст джерелаАнотація:
Malaria is currently one of the most imperative parasitic diseases in developing countries. Artesunate has a short half-life, low aqueous solubility and resultant poor and erratic absorption upon oral administration, which translate to low bioavailability. Mefloquine is eliminated slowly with a terminal elimination half-life of approximately 20 days and has neuropsychiatric side effects. Novel drug delivery systems have been utilised to optimise chemotherapy with currently available antimalarial drugs. Pheroid™ technology is a patented drug delivery system which has the ability to capture, transport and deliver pharmaceutical compounds. Pheroid™ technology may play a key role in ensuring effective delivery and enhanced bioavailability of novel antimalarial drugs. The aim of this study was to evaluate the possible efficacy and bioavailability enhancement of the selected antimalarial drugs, artesunate and mefloquine, in combination with Pheroid™ vesicles.
The in vitro efficacy of artesunate and mefloquine co-formulated in the oil phase of Pheroid™ vesicles and entrapped in Pheroid™ vesicles 24 hours after manufacturing were investigated against a 3D7 chloroquine-sensitive strain of Plasmodium falciparum. Parasitemia (%) was quantified with flow cytometry after incubation periods of 48 and 72 hours. Drug sensitivity was expressed as 50% inhibitory concentration (IC50) values. An in vivo bioavailability study with artesunate and mefloquine was also conducted in combination with Pheroid™ vesicles, using a mouse model. A sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to analyse the drug levels. C57 BL6 mice were used during this study. The selected antimalarial drugs were administered at a dose of 20 mg/kg with an oral gavage tube. Blood samples were collected by means of tail bleeding.
The in vitro drug sensitivity assays revealed that artesunate, co-formulated in the oil phase of Pheroid™ vesicles and evaluated after a 48 hour incubation period, decreased the IC50 concentration significantly by 90%. Extending the incubation period to 72 hours decreased the IC50 concentration of artesunate, also co-formulated in the oil phase of Pheroid ™ vesicles significantly by 72%. No statistically significant differences between the reference and Pheroid™ vesicle groups were achieved when artesunate was entrapped 24 hours after manufacturing of Pheroid™ vesicles. Mefloquine co-formulated in the oil phase of Pheroid™ vesicles and evaluated after a 48 hour incubation period decreased the IC50 concentration by 36%. Extending the incubation period to 72 hours increased the efficacy of the Pheroid™ vesicles and the IC50 concentration was significantly decreased by 51%. In contrast with the results obtained with artesunate, entrapment of mefloquine in Pheroid™ vesicles 24 hours after manufacturing decreased the IC50 concentration significantly by 66%.
The LC-MS/MS method was found to be sensitive, selective and accurate for the determination of artesunate and its active metabolite, dihydroartemisinin (DHA) in mouse plasma and mefloquine in mouse whole blood. Most of the artesunate plasma concentrations were below the limit of quantification in the reference group and relatively high outliers were observed in some of the samples. The mean artesunate levels of the Pheroid™ vesicle group were lower compared to the reference group, but the variation within the Pheroid™ vesicle group lessened significantly. The mean DHA concentrations of the Pheroid™ vesicle group were significantly higher. DHA obtained a higher peak plasma drug concentration with the Pheroid™ vesicle group (173.0 ng/ml) in relation to the reference group (105.0 ng/ml) and at a much faster time (10 minutes in Pheroid™ vesicles in contrast to 30 minutes of the reference group). Pharmacokinetic models could not be constructed due to blood sampling per animal limitation. The incorporation of mefloquine in Pheroid™ vesicles did not seem to have improved results in relation to the reference group. No statistical significant differences were observed in the pharmacokinetic parameters between the two groups. The relative bioavailability (%) of the Pheroid™ vesicle incorporated mefloquine was 7% less bioavailable than the reference group.Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2010.
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Jao, Irwin Yui-Wen. "Capability enhancement through cross-border contract manufacturing alliances : a study of Taiwanese information technology firms." Thesis, London Business School (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244179.
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Cheng, Chun Fai. "Modeling of polysilicon thin-film transistors formed by grain enhancement technology-metal-induced lateral crystallization /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202004%20CHENG.
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Bengtsson, Martin, and Emil Ågren. "Image enhancement of license plates in images using Super Resolution." Thesis, Linköpings universitet, Medie- och Informationsteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-121682.
Повний текст джерелаАнотація:
Bildgruppen på enheten för dokument och informationsteknik hos SKL har ett behov av att kunna förbättra bilder med extremt låg upplösning. Detta bildmaterial kan komma från diverse övervakningskameror där det intressanta objektet endast utgör en väldigt liten del, i detta fall registreringsskyltar på förbipasserande bilar. Att skapa en högupplöst bild av en registreringsskylt utav ett fåtal lågupplösta bilder är ett välkänt problem med ett flertal förslag på metoder och lösningar. I denna rapport kommer vi att undersöka vilka metoder som passar bäst vid bildförbättring av registreringsskyltar. Vi kommer även att skapa ett användargränssnitt där man kan läsa in en bild och välja mellan att automatiskt hitta registreringsskylten i bilden eller att manuellt klippa ut den. Efter att man erhållit en bild innehållandes endast registreringsskylten ska de olika implementerade bildförbättringsmetoderna kunna användas. Slutligen diskuteras vilka för- och nackdelar de respektive metoderna har. Förslag på eventuella förbättringar och hur man kan utveckla dessa metoder vidare presenteras därtill.
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Hozhabr, Sassan. "Enhancement of interfacial adhesion in polymer blends of polypropylene and poly (ethylene vinyl alcohol copolymer)." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60598.
Повний текст джерелаАнотація:
In the present study a blend system containing polypropylene (PP) and ethylene vinyl alcohol copolymer (EVOH) was considered. Maleic anhydride grafted polypropylene (MAH-g-PP) was used to improve adhesion at the interface. The preliminary work was conducted in a batch mixer and then extended to a single and a twin screw extruders.The results in the batch mixer demonstrated that blends containing high levels of MAH have well bonded morphology and impact strengths comparable to pure materials. Statistical analysis of the results showed that at processing temperature of 200$ sp circ$C and mixing time of 13 minutes, the highest impact strength and largest elongation at break were obtained.
In the extruder the morphological studies revealed the presence of a layered structure in the core region of the samples when a slit die was employed. The oxygen permeability of extruded samples with EVOH content higher than 20vol% resembled multi-layer systems.
Impact strength of extruded ribbons drastically improved by increasing the maleation level to 0.2wt% and precompounding the virgin resins in a twin screw extruder. Morphological observations however, revealed some disruption in the layered structure and consequently decline of oxygen barrier properties.