Dissertations / Theses: 'Integrated coil'

1

Tobgay, Sonam. "Novel concepts for RF surface coils with integrated receivers." Link to electronic thesis, 2004. http://www.wpi.edu/Pubs/ETD/Available/etd-0419104-141545.

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2

Altwieb, Miftah Omar. "Modelling and optimisation of heat exchanger integrated in fan coil unit." Thesis, University of Huddersfield, 2018. http://eprints.hud.ac.uk/id/eprint/34544/.

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The Fan Coil Unit (FCU) is an integral part of heating, ventilation and air conditioning systems used in residential and commercial buildings. One main component of this device is a multi-tube and fin heat exchanger. Improvement of thermal performance in such heat exchangers is vital for improved performance of FCU. Performance improvements in the FCUs are mainly limited by available technology, manufacturing capabilities and overall cost effectiveness of the design. Better thermal performance usually comes at a cost of higher pressure drop or more expensive materials and manufacturing costs. In this thesis, a global framework for design and optimisation was developed taking into account overall costs of design, manufacturing and operation. Full 3D CFD models of multi-tube and fins heat exchanger were developed to investigate complex and non-uniform flow on water and air sides of the device. The CFD models were developed to enable local heat transfer analysis within the FCU. Experimental setup to evaluate performance of the heat exchanger has been designed and built. Different configurations of heat exchanger were tested experimentally and numerically, including the baseline configuration, so called plain fins. More efficient design of louvre fins and and fins with vortex generating mechanism (perforation in the fin surfaces) were also investigated. Best thermal performance was found to be for the perforated louvre fins. CFD model was validated against experimental results and obtained data was used to create a novel semi-analytical prediction model for Fanning friction factor (f) and Colburn factor (j). Appropriate costs calculation model was also developed and employed for total costs estimation of the FCU over the period of 15 years. The framework proposed in this thesis for optimised design and development strategy of heat exchangers resulted in development of a novel design which offers significant improvements in comparison to the current design. This new optimised design of the heat exchanger (with perforation in louvre fins) increased thermal performance by additional 10% while the total costs increased by only 6%.

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Rata, Mihaela. "Endocavitary applicator of therapeutic ultrasound integrated with RF receiver coil for high resolution MRI-controlled thermal therapy." Phd thesis, Université Claude Bernard - Lyon I, 2009. http://tel.archives-ouvertes.fr/tel-00692346.

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This thesis presents technical and methodological developments aiming tooffer a viable alternative for the treatment of digestive cancers (rectum and esophagus). Compared to the standard methods of therapy, the high intensity contact ultrasound guided by MRI is a less invasive approach. MRI offers 2 advantages: good spatial resolution, and real-time temperature control. This treatment method requires efficacy and safety. Three prototypes of RF coil integrated with ultrasound transducers were built in order to increase the spatial and temporal resolution ofthe MR images, and the accuracy of the temperature measurement. The integrated coils showed a better sensitivity compared to a standard extracorporeal coil. Anatomical (voxel 0.4x0.4x5 mm3)and thermometry (voxel 0.75x0.75x8 mm3, 2s/image) high resolution MR images were acquired in-vivo. The temperature was measured, within a radius of 20 mm from the balloon, with a standard deviation <1°C. The flow artifacts caused by the water circulating inside the cooling balloon could be shifted out of the region of interest. The temperature evolution was controlled automatically, at different depths, with one control point per beam. The controller showed a good accuracy during in-vivo experiments (standard deviation less than 5%). The phased-arrayultra sound transducer permits the successive activation of multiple beams during the same dynamic of sonication. Simulations were conducted in order to offer an optimal treatment planning for a defined tumor. A new design of ultrasound transducer with 256 elements with revolution symmetry, based on a natural geometrical focalization, was proposed.

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Kızıldağ, Eren C. "Improved magnetic resonance chemical shift imaging at 3 Tesla using a 32-channel integrated RF-shim coil array." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/108976.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 87-93).
In vivo chemical shift imaging is an imaging modality which uses the so-called chemical-shift phenomenon to quantitate brain metabolites spatially, therefore renders the study of brain metabolism and neurodegenerative diseases possible and eases diagnosis of tumors. However, the method is highly vulnerable to local main magnetic field (Bo) inhomogeneities arising from magnetic susceptibility differences which is predominantly present in air-tissue interfaces. Such magnetic field inhomogeneities result in number of imaging artifacts including chemical shift displacement of metabolites, spectral line broadening as well as complicated water and lipid suppression; which reduce spectral quality. The main goal of this work is to compensate Bo imperfections and therefore mitigate aforementioned artifacts to earn enhanced spectral quality with the aid of a recently introduced, novel, 32-channel integrated RF-shim coil hardware. Experimental results indeed demonstrate sharper spectral lines with narrower line widths and improved water suppression performance in the regions with poor BO conditions with the application of the shim coil hardware.
by Eren C. Kizildag.
S.M.

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5

Haemer, Gillian. "Optimizing Radio Frequency Coil Performance for Parallel Magnetic Resonance Imaging at Ultra High Field| Evaluation and Optimization of Integrated High Permittivity Materials." Thesis, New York University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10751718.

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In the time since magnetic resonance imaging (MRI) was introduced, scientific progress has allowed for a factor-of-ten increase in static magnetic (B₀) field strength, and has developed MR into a clinical workhorse. This increase in B₀ field strength has the potential to provide significant gains to the inherent signal-to-noise ratio of resulting images. However, this progress has been limited by degradations in the spatial homogeneity of the radiofrequency magnetic fields used for nuclear excitation (B₁), which have wavelengths comparable to the dimensions of the human body in modern high-field MRI. Techniques to improve homogeneity, including B₁-shimming and parallel transmission, require multi-element radiofrequency (RF) transmit arrays. Increasing B₀ field strength is also associated with an increase in the deposition of RF energy into the subject, clinically measured and regulated as Specific energy Absorption Rate (SAR), deposited in tissue during image acquisition. High permittivity materials (HPMs) have the potential to augment RF coil performance outside of B₁-shimming or parallel transmission methods. The use of HPM pads placed in existing RF coils has also been shown to provide a potential reduction of array SAR in nuclear excitation, as well as potential performance benefits in signal reception. However, the question of how best to strategically use these materials in the space between the coil and the sample in order to maximize benefit and alleviate any potential problems has not yet been thoroughly addressed.

The contributions presented in this dissertation demonstrate the potential utility of the integration of HPMs into transmit-receive RF coils, as an integral component of the hardware design. A framework to quickly choose the relative permittivities of integrated materials, optimized relative to an absolute standard (rather than relative to a different design) is introduced, and used to demonstrate that readily available material properties can provide significant improvements in multi-element transmit performance. A subsequent analysis of practical effects and limitations of these materials on the RF coil resonance properties is performed, including the description of a unique adverse resonance splitting phenomenon and how to avoid it. A transmit/receive RF coil design is built and evaluated, first on its own experimentally, and then in simulation with a helmet-shaped high permittivity material former to examine the benefits and challenges associated with HPM integration into RF coils.

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Black, Justin Durant. "Evaluation and Development of Actuators for Lamina Emergent Mechanisms with Emphasis on Flat Solenoids." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3208.

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Lamina emergent mechanisms (LEMs) can provide a way to meet the demand for more compact and inexpensive mechanisms. Previous research has developed LEM designs and identified applications for them, but many applications would benefit from suitable actuation techniques. This thesis presents the design considerations and a variety of applicable methods for internal and external LEM actuation in the macro scale. Integrated LEM actuator possibilities have been identified, each with its advantages and disadvantages depending on the application. Shape memory alloys are especially compatible with LEMs. Traditional actuators have also been discussed as a way of actuating a LEM from the outside for cases in which space constraints allow it. The feasibility of new internal actuators using basic actuation principles, especially flat solenoids, has been explored. The magnetic field distribution along the axis of a high-aspect-ratio solenoid has been derived. Analytical and experimental results show that the output force of a high-aspect-ratio solenoid is suitable for LEMs. A pseudo-solenoid conceptual prototype was manufactured and evaluated, revealing challenges for which solutions have been recommended.

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7

Thelin, Peter. "Design and Evaluation of a Compact 15 kW PM Integral Motor." Doctoral thesis, KTH, Electrical Systems, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3322.

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This thesis deals with the integral motor of tomorrow, and particularly with a variable speed, sensorless permanent magnet synchronous motor with an integrated converter. The rated power is 15 kW at 1500 r/min. The outer dimensions are approximately the same as for the equivalent standard induction motor.

Control strategies for pumps and fans, i.e. suitable loads for variable speed motors, are briefly described. The huge energy savings that can be made by reducing the speed instead of throttling/choking the flow are pointed out. Compared to installing an induction motor with a separate converter, a PM integral motor will probably pay-off in less than a year.

A totally analytical expression for calculating the airgap flux density of permanent magnet motors with buried magnets is derived. The analytical expression includes axial leakage, and iron saturation of the most narrow part of the magnetic circuit of the machine.

A computer program for optimization of PM motors with buried magnets has been developed. It was used to design the manufactured prototype PM integral motor, and the parameters are investigated with analytical and/or FEM calculations. The optimization program is also used to suggest nearoptimum pole numbers for desired powers (4-37 kW) and speeds (750- 3000 r/min) of inverter-fed PM motors. Results show that compact buried PM motors should have relatively large airgaps and high NdFeB-magnet masses to improve the efficiency. Ferrite magnets are unsuitable.

Measurements on the manufactured PM motor, the novel concept of stator integrated filter coils, and the complete PM integral motor are presented. Special attention was given to temperature and overall efficiency measurements.

The rotor cage losses were investigated by time-stepping FEM. Four short circuit fault conditions were also examined in order to evaluate the risks of demagnetization of the buried magnets.

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8

Корчака, Микола Олександрович. "Інтегральні сенсори струму на ефекті Холла з магнітною компенсацією напруження." Master's thesis, КПІ ім. Ігоря Сікорського, 2020. https://ela.kpi.ua/handle/123456789/40371.

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Дисертація складається зі вступу, п’яти розділів, висновків, списку використаних джерел. Загальний обсяг дисертації становить 94 сторінки, у тому числі 85 сторінок основного тексту, 65 рисунків, 25 таблиць, список використаних джерел із 56 найменувань. Метою дисертаційної роботи є розробка напівпровідникового інтегрального сенсора струму на ефекті Холла зі схемою компенсації дії напруження, яка використовує інтегровано котушку індуктивності. При розв’язанні поставлених у роботі завдань для розробки і проєктування інтегрального сенсора струму на ефекті Холла використано теорію електричних кіл, теорію авторегулювання та керування. Математичні розрахунки виконано у програмному середовищі MATLAB. Симуляції електричних кіл проведено у програмному середовищі Cadence Virtuoso. Під час симуляцій використано методи Монте-Карло для статистичного врахування випадкових процесів під час виготовлення напівпровідникових інтегральних мікросхем. В результаті роботи було спроєктовано інтегральний сенсор струму на ефекті Холла з схемою компенсацією дії напруження, яка дозволяє забезпечити незмінність чутливості елемента Холла в межах не більше 1% впродовж тривалої експлуатації пристрою. Новизна роботи полягає в тому, що схема компенсації реалізовано повністю в аналоговій частині і не потребує додаткових обрахунків в цифровій частині сенсора. Результати роботи можуть бути використані не лише для сенсорів струму на ефекті Холла, але і для інших інтегральних схем, які використовують елементи Холла, наприклад для відстеження об’єктів у просторі, вимірювання швидкості та напрямку обертання двигуна, для безконтактного перемикання. Для подальших дослідження необхідно виготовити прототип спроєктованого сенсора на кремнії і продовжити аналіз його характеристик.
The thesis consists of an introduction, five sections, conclusions, a list of sources used. The total volume of the thesis is 94 pages, including 85 pages of the main text, 65 figures, 25 tables, a list of used sources from 56 titles. The purpose of the thesis is to develop a semiconductor integrated current sensor on the Hall effect with a voltage compensation circuit that uses an integrated inductor. The theory of electric circuits, the theory of self-regulation and control is used in solving the tasks set in the work for the development and design of an integrated current sensor on the Hall effect. Mathematical calculations were performed in the MATLAB software environment. Simulations of electric circuits were performed in the Cadence Virtuoso software environment. During the simulations, Monte Carlo methods were used to statistically consider random processes in the manufacture of semiconductor integrated circuits. As a result of work the integrated current sensor on Hall effect with the scheme of stress compensation which allows to provide invariability of sensitivity of a Hall element within no more than 1% during long operation of the device was designed. The novelty of the work is that the compensation scheme is implemented entirely in the analog domain and does not require additional calculations in the digital part of the sensor. The results can be used not only for Hall effect current sensors, but also for other integrated circuits that use Hall elements, such as tracking objects position, measuring the speed and direction of rotation of the motor, for contactless switching. For further research it is necessary to make a prototype of the designed sensor on silicon and to continue the analysis of its characteristics.

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9

Khan, Muneeb Ullah. "Contribution to the design and fabrication of an integrated micro-positioning system." Thesis, Compiègne, 2014. http://www.theses.fr/2014COMP1671/document.

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L’objectif de la thèse est de développer un dispositif de micro positionnement intégrant à la fois les actionneurs et les capteurs. Un dispositif a été conçu afin de réaliser des déplacements dans les plans sur une course millimétrique. Le dispositif compact ne nécessite pas de système de guidage additionnel et selon le mode d’utilisation de ces moteurs, il est capable de réaliser des translations dans le plan ou des rotations autour d’un axe perpendiculaire au plan. Le dispositif comprend quatre moteurs électromagnétiques linéaires fixés orthogonalement sur une structure en forme de croix. Chaque moteur consiste en une paire de bobines planes entrelacées fixe et une barre ’aimants mobile. Un capteur de déplacement intégré dans la structure en croix permettant de mesurer le déplacement de celle-ci a été conçu et fabriqué. Ce capteur est constitué d’une tête de mesure à fibres optiques placé face à un réseau en silicium réalisé par des techniques de microfabrication. Afin de minimiser les erreurs d’assemblage, la structure en croix a également été micro fabriquée. Le dispositif est capable de réaliser un déplacement de 10 mm et une rotation de ±11° autour de l’axe perpendiculaire au plan du dispositif. La résolution de déplacement du dispositif est de 1,4 µm avec une précision de 31 nm en boucle fermée. Le dispositif peut également atteindre une vitesse de déplacement de 12 mm/s
The objective of thesis is to develop an integrated micro positioning system for micro applications. A unique micro positioning system design capable to deliver millimeter level strokes with pre-embedded auto guidance feature in micro application has been realized. The design integrates, a stack of orthogonally arranged four electromagnetic linear motors. Each linear motor consists of a fixed planar electric drive coil and mobile permanent magnet array. The optimal design of the system delivers a small footprint size. In addition, to measure and control the displacement, a high resolution compact optical displacement measurement sensor has been designed and fabricated in silicon material using microfabrication technology. Furthermore, a light weight silicon cross structure was fabricated using dry etching technology to reduce components assembly errors. The device is capable to deliver 10 mm displacement stroke with a rotation of ±11° about an axis perpendicular to the plane of the device. The displacement resolution of the device is 1.4 µm with a precision of 31 nm in closed loop control. The device can realize displacement with a speed of 12 mm/s

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10

Wimmer, Christopher Lance. "Optimization of Integrated Coal Cleaning and Blending Systems." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/50493.

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The fundamental requirement for a coal preparation plant is to transform low value runof- mine (ROM) material into high value marketable products. The significant aspect relative to the plant is that any gain in efficiency flows almost entirely to the "bottom line" for the operation. The incremental quality concept has gained wide acceptance as the best method to optimize the overall efficiency of the various cleaning circuits. Simply stated, the concept requires that all the cleaning circuits operate as near as possible to the same incremental quality. To ensure optimal efficiency, a plant that receives ROM feed from multiple sources must develop a strategy to operate at the same incremental quality, which yields wide ranges in product qualities from the individual ROM coals. In order to provide products that meet contract specifications, clean coal stockpiles can be utilized to accept coals with various qualities, such as "premium," " low," and "filler" qualities, with shipments formulated from the stockpiles to meet product specifications. A more favorable alternative is raw coal blending to produce the specified clean coal qualities. This study will review the incremental quality concept and present case studies in applying the concept to meet product specifications.
Master of Science

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11

Roxas, Jennifer Lising, and Jennifer Lising Roxas. "Novel Virulence Strategies of Enteropathogenic Escherichia Coli: An Integrated Study." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/625671.

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Enteropathogenic Escherichia coli (EPEC) is a Gram-negative bacteria responsible for significant morbidity and mortality in young children. EPEC elaborates a type III secretion system (T3SS), which translocates bacterial effector proteins into the host intestinal epithelial cell. To this date, 23 effector proteins are known to be secreted by EPEC. Over the past two decades, traditional studies uncovered the functions of some of these effector proteins. While there was an initial rise in the EPEC effector function discoveries, we now observe a plateau in the identification of host-EPEC interactions. Thus, the aim of my dissertation is to define novel virulence strategies in EPEC pathogenesis, and to demonstrate how traditional reductionist and global systems biology approaches can be utilized in uncovering functions of individual effectors, as well as the complex interplay of effectors in modulating host functions. Specifically, we defined the novel cytoprotective function of a T3SS effector EspZ. We further illustrated the complex interplay of EPEC effectors by defining how EPEC utilizes EspZ and EspF to dynamically regulate the prosurvival epidermal growth factor receptor signaling pathway. Finally, by integrating comparative proteomics and traditional reductionist approaches, we identified a novel function for EspH, and defined the mechanism by which EspH perturbs epithelial cell structure and function.

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12

Ehrle, Rainer R. "Funktions- und Strukturanalyse eines integralen Cytoplasmamembranproteins /." [S.l.] : [s.n.], 1997. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB6564363.

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13

Basu, Kohinoor. "Feasibility of an Integrated Thin Seam Coal Mining and Waste Disposal System." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/9578.

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The depletion of more attractive thicker and easily accessible coal seams in the central Appalachia will direct attention towards the extraction of coal seams thinner than 28 in. This thesis investigates the feasibility of an integrated mining and backfilling system applicable to thin seams. Two conceptual mining systems, namely Auger mining and Self Advancing Miner, have been proposed for this purpose. Both these systems are designed to remotely mine coal from the seams. Several attempts were made in the past to mine coal in a similar fashion but were not very successful due to several problems inherent to thin seams. The lack of effective steering techniques, accurate coal/rock interface and pillar thickness detection techniques were the main shortcomings of the systems. These problems were addressed in the proposed conceptual mining systems. Several coal/rock interface and rib thickness detection techniques currently available in the market or in the prototype stage have been discussed. Recent developments in coal/rock interface detection and direction sensing techniques have good potential in alleviating the previously encountered problems. Sensitivity analyses have been performed to assess the of effect critical mining parameters on the production potential of these systems. The self advancing miner has been found to be more promising than auger mining. Conceptual panels and face layouts for both systems have been included. Two types of filling methods namely pneumatic and hydraulic are considered applicable under thin seam conditions. A backfilling technique using rubber hoses for fill placement can be applied with both methods. Sensitivity analysis have been performed to establish the relationship between face operation cost, filling cost per ton and development cost per foot. Resulting analyses indicate that panel cost per short ton of coal is more sensitive to filling cost than on development cost.
Master of Science

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14

Frumerie, Clara. "Functional characterization of a phage integrase and its possible use in gene therapy /." Stockholm : Department of genetics, microbiology and toxicology, Stockholm university, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-397.

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15

Altekruse, Sean Fitzgerald. "Characterization of Climical and Commensal Escherichia coli Isolates from an Integrated Turkey Operation." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/29668.

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Pathogenic E. coli infections cause approximately one quarter of disease losses in commercial turkey flocks. A small subgroup of E. coli causes most infections. Epidemiologic studies of this disease have been hindered by a lack of reliable markers to discriminate between pathogenic and fecal E. coli and by the diversity of poultry strains. Reliance on antimicrobials to control E. coli infections has caused widespread antimicrobial resistance. One hundred five clinical E. coli were obtained, and 1104 isolates were collected from fecal specimens of 20 flocks in an integrated turkey operation. Biochemical fingerprinting and antimicrobial susceptibility tests were performed on all isolates, and somatic antigen serologic testing and PCR for potential virulence genes were conducted on 299 strains including all clinical isolates and fecal isolates that had similar traits to clinical isolates. Most avian E. coli infections were caused by a few clonal strains that were uncommon in normal fecal flora. The potential virulence genes iss, K1 and tsh were detected more frequently among clinical than fecal isolates; however, the pattern of occurrence did not suggest that these genes were useful markers for identifying pathogenic strains. Syndromes consistent with colibacillosis were the most commonly reported illness and principal rationale for antimicrobial therapy in sampled flocks. Most clinical E. coli isolates were resistant to gentamicin, sulfamethoxazole and tetracycline. Although resistance to fluoroquinolones and Î²-lactam antibiotics occurred less frequently, the potential for resistance to emerge to these antimicrobials was evident. A Bayesian model to estimate sample size confirmed the diversity of avian fecal E. coli strains. Studies are needed to define risk factors for infection with and identify markers for avian pathogenic E. coli strains. These research priorities are complementary and may lead to the identification of new interventions to prevent this important infectious disease of poultry.
Ph. D.

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Chakraborty, Amal. "An integrated computer simulator for surface mine planning and design." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/90920.

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In the increasingly competitive coal market, it is becoming more important for coal operators to develop mathematical models for surface mining which can estimate mining costs before the actual mining begins. The problem becomes even more acute with the new reclamation laws, as they affect surface coal mining methods, productivity, and costs. This study presents a computer simulator for a mountaintop removal type of surface mining operation. It will permit users to compare the costs associated with different overburden handling and reclamation plans. It may be used to minimize productivity losses, and, perhaps, to increase productivity and consequently to reduce operating costs through design and implementation of modified mountain top removal methods.
M.S.

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Harton, Renee M. "Characterization of polygrama green photopolymer for Compact Optoelectronic Integrated Neural (COIN) coprocessor applications." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44461.

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Includes bibliographical references (leaves 33-34).
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2008.
The research described in this thesis is a portion of a larger project within the Photonic Systems Group at MIT to design Compact Optoelectronic Integrated Neural (COIN) co processor [13]. The choice of photopolymers is critical in determining the performance of COIN processors as we look at ways to increase the diffraction efficiency. The focus of this research was to optically characterize Polygrama Green, a photopolymer that is sensitive to green light (514 nm). We were able to plot diffraction efficiency versus the exposure energy density for a series of gratings. We found the maximum diffraction efficiency to be that of the 678 mJ/cm2 grating with a value of 29.5%. We were able to fit the data to a sin2(x) curve with a X2- value of 20.79. We concluded that this somewhat high X2-value is due to our low number of data points. However, using Kogelnik's equation and the measured diffraction efficiency of each grating, we were also able to calculate the An, of each grating. This analysis shows that Polygrama Green seems to be a promising candidate for the photopolymer used in subsequent optoelectronic neural network applications.
by Renee M. Harton.
S.B.

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18

Maneya, George Jameson. "An integrated study of coal geology and potential environmental impact assessment at Mchenga Coal Mine in Livingstonia Coalfield in Malawi." Thesis, University of Fort Hare, 2012. http://hdl.handle.net/10353/480.

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This study was carried out on the main coal-producing and the extensively block-faulted area of Mchenga Coal Mine, southeast of the 90 km2 intracratonic Livingstonia Coalfield in the north of Malawi. It was initiated against the background of indistinct information on coal geology, shortage of energy and potential environmental threats due to mine activities. The study aimed at integrating investigations of characterization of the lithostratigraphy, coal seam correlation, coal quality determination, examination of the mineralogy and geochemistry of coal and hosts rocks, assessment of water quality and providing information for mining and potential environmental and water quality impact assessment in the study area. The methodologies used in this study include literature review, field visits, mapping, sites selection and characterization, borehole logging, geochemical analyses, data processing and interpretation. The geochemical analyses include proximity analysis of coal quality, microscopy and X-ray Diffraction for mineralogy and petrology, X-ray Fluorescence (XRF) for rock geochemistry and Atomic Absorption Spectrometry for determination water geochemistry. The results have shown that a) The Coal Measures comprises of four to six coal seams in different localities, and the occurrence is flat and gently dipping southeast and are correlated. Thicknesses of the coal seams vary from 0.10m to 3.0m with some notable lateral and horizontal variations. Thick and workable seams occupy the lower portion of the Coal Measures and are exposed along the North Rumphi River bank; b) Coal quality belongs to sub-bituminous ‘A’ to ‘C’ on ASTM classification (1991), being characterised by low moisture content (0.8 to 1.3 wt percent) and sulphur content (0.49 to 0.85 wt percent), high ash content (9.0 to 17 wt percent) and volatile matter (24 to 32.9 wt percent), fixed carbon (53.6 to 62.6 wt percent), calorific value (7,015 to 7,670 kcal/kg); c) Mineral matters constitute approximately 9.55 to 38.34 wt percent of the coal samples, predominantly clays (interstratified illite/smectite and kaolinite) with varying proportions of quartz, mica and feldspars, as well as minor calcite and pyrite and their geochemistry, being characterised by enrichment of SiO2 from 5.37 to 20.56 wt percent, Al2O3 (2.63 to 11.21 wt percent) and K2O (0.32 to 3.65 wt percent) with trace concentrations of CaO (0.04 to 0.41 wt. percent), MgO (0.08 to 0.65 wt percent) and P2O5 (0.018 to 0.037 wt percent) and Na2O concentration notably below 0.01 wt percent; d) Calcite and pyrite constitute minor concentration in both sandstones and shales; e) Water quality in the area is characterised as two groups of acidic (pH 3.3-6.4) and near-neutral to slightly alkaline (pH 6.9-7.3) and low pH, high TDS, SO42- and EC are noted at the coal crusher plant which points out to high leaching of trace elements such as Pb and Fe. Na++K+ are dominant in upper sections of North Rumphi and Mhlepa Rivers. Ca2+ cations are dominant at crusher plant, underground mine and lower section of Mhlepa; f) Based on the geochemistry analysis, Na and trace elements such as Ti, V, Mn, Fe, Zn, Rb, Sr and Zr from coal and host rocks have the ability to contribute significantly to deterioration in the ground and surface water quality in the study area. It can be concluded that the coals of the Livingstonia Coalfield belong to Gondwana group deposited in sub-basin with multiple seams embedded in sandstone and shale host rocks.

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19

Gregory, Sean. "Development of instrumentation for the investigation of surface regeneration for candle filters." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=2238.

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Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains xii, 102 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 80-81).

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Weyer, Vanessa Derryn. "Surface-strip coal mine rehabilitation risk assessment : the development of an integrated rehabilitation risk assessment model for use in South Africa and Australia." Thesis, University of Pretoria, 2020. http://hdl.handle.net/2263/77899.

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Surface-strip coal mine rehabilitation planning in South Africa and Australia is immature. Rehabilitation risk assessment, despite being advocated by leading practice guidelines and in some instances by legislation, is conducted with minimum requirements often met by rehabilitation professionals. Specialist data is gathered during mine approval and for the environmental impact assessment process. However, the focus of this is toward assessing mining impacts and not for rehabilitation risk assessment. Quantitative, integrated, multi-disciplinary rehabilitation risk assessment is seldom undertaken. This thesis provides a methodology towards the development of a quantitative, integrative, multi-disciplinary rehabilitation risk assessment model. Its purpose being to 'profile' surface-strip coal mine sites, in terms of their rehabilitation risk and potential for rehabilitation failure, from the outset of mine operations, with adjustments possible progressively during mine operations. The methodology was developed by first reviewing techniques suitable for the development of the model, as well as techniques developed by others. Bayesian networks (BN) were found to be the most suited. A R2AIN framework was then provided as a process towards developing several BN risk event models that can amalgamate to form a synthesis rehabilitation risk assessment model. A case study soil compaction BN model was used to demonstrate the framework in South Africa and Australia. The case study showed that it is possible to integrate and quantify rehabilitation risk, and most importantly to segregate risk into discrete contributing multidisciplines for analysis. Risk percentages can be calculated per multi-discipline, per mine phase, per site, to aid site risk ‘profiling’. It is recommended that further risk event BN models be prioritised for development and that a rehabilitation risk assessment model be developed to synthesise these into one model. This will require continuous improvements in the method, to build confidence, including extensive risk event and synthesis BN model evaluation and testing; improved BN input node states and values; and simplification of the conditional probability table construction method. Adaptation to other mining types, development activities and other regions should be investigated, as well as spatial linkages to geographic information systems. This research contribution improves upfront mine rehabilitation planning and decision making, providing improved tools and techniques than what currently exist.
Thesis (PhD)--University of Pretoria, 2020.
Geography, Geoinformatics and Meteorology
PhD
Unrestricted

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21

Alali, Walid Qasim. "Longitudinal study of antimicrobial resistance among Escherichia coli isolated from integrated multi-site cohorts of humans and swine." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2434.

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22

Flynn, Zara Nicole. "Dynamic characterisation of the caving process around longwall coal mines using integrated microseismology and numerical modelling." Thesis, University of Liverpool, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250537.

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23

Long, Henry A. III. "Analysis of Biomass/Coal Co-Gasification for Integrated Gasification Combined Cycle (IGCC) Systems with Carbon Capture." ScholarWorks@UNO, 2011. http://scholarworks.uno.edu/td/1371.

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In recent years, Integrated Gasification Combined Cycle Technology (IGCC) has become more common in clean coal power operations with carbon capture and sequestration (CCS). Great efforts have been spent on investigating ways to improve the efficiency, reduce costs, and further reduce greenhouse gas emissions. This study focuses on investigating two approaches to achieve these goals. First, replace the subcritical Rankine steam cycle with a supercritical steam cycle. Second, add different amounts of biomass as feedstock to reduce emissions. Finally, implement several types of CCS, including sweet- and sour-shift pre-combustion and post-combustion. Using the software, Thermoflow®, this study shows that utilizing biomass with coal up to 50% (wt.) can improve the efficiency, and reduce emissions: even making the plant carbon-negative when CCS is used. CCS is best administered pre-combustion using sour-shift, and supercritical steam cycles are thermally and economically better than subcritical cycles. Both capital and electricity costs have been presented.

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24

Kim, Hyung Rae. "Coal-Direct Chemical Looping Combustion Process for In-Situ Carbon Dioxide Capture – Operational Experience of Integrated 25-kWth Sub-Pilot Scale Unit." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1352996758.

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25

Durazo, Jacqueline Nicole. "The impacts of cleaner energy policies on coal-dependent Appalachia and our response options." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/113512.

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Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Through conducting an extensive literature review of current policies, interviewing Appalachian residents, and surveying the energy and employment landscapes both regionally and nationally, this thesis aims to shed light on the effect cleaner energy policies have on employment in the Appalachian region. Most importantly, it aims to explain how we as a nation can help support policies that promote employment in sectors other than coal, which has perpetuated poverty and financial insecurity. Understanding past trends and potential future forecasts, while also establishing clear communication with the community in order to ensure proper integration of their needs, will help guide the creation of successful public policy. This work will explain how and which industries we as a nation moving forward should support in order to promote employment in the region in more diverse, sustainable, and healthy ways. Furthermore, there is a growing local entrepreneurial spirit among Appalachia's residents. This passion could be utilized to bolster support moving forward for policies that encourage diversified sources of income such as abandoned land mine reclamation, agriculture, manufacturing the parts for renewable energy technology, and more. This thesis outlines the necessary steps and suggests methods to take for that to happen, such as taking into account the local needs of each county, integrating their feedback from the beginning and at every stage of the development cycle, and ultimately connecting the somewhat isolated region with the rest of the national and global market.
by Jacqueline N. Durazo.
S.M. in Engineering and Management

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Sander, Frank [Verfasser]. "Thermodynamic Analysis of Coal Fired Power Generation Cycles with Integrated Membrane Reactor and CO2 Capture / Frank Sander." Aachen : Shaker, 2012. http://d-nb.info/1069047252/34.

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27

Haneburger, Ina Maria Suntka. "Insights into the molecular signal perception mechanism of the membrane-integrated transcriptional activator CadC of Escherichia coli." Diss., Ludwig-Maximilians-Universität München, 2011. http://nbn-resolving.de/urn:nbn:de:bvb:19-160780.

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28

Tadele, Wegene Haile. "Design of optoelectronic activation, local memory and weighting circuits for Compact Integrated Optoelectronic Neural (COIN) Co-processor." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/106739.

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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2015.
Cataloged from PDF version of thesis. Pages 7 and 8 are missing.
Includes bibliographical references (pages 99-103).
The Compact Integrated Optoelectronic Neural (COIN) Co-processor, a prototype of artificial neural network implemented in hybrid optics and optoelectronic hardware, aims to implement a multi-layer neural network algorithm by performing parallel and efficient neural computations. In this thesis, we design and implement optoelectronic thresholding (activation), weighting and memory circuits for the COIN processor. The first version involved the design of fixed thresholding and weighting functions. The second version incorporated a local capacitive memory element as well as variable weighting schemes. The third version introduces an additional flexibility for variable thresholding by changing the bias voltages of control transistors. A 9x9 array of proof of concept printed circuit board (PCB) with an area of 4.5x 4.5 in² and total power consumption of 1.37W was designed and tested for version-I optoelectronic neuron architecture. A spice simulation was performed for the last two versions for integrated circuit (IC) implementation. The work developed in this thesis provides some guidance on the design of optoelectronic neural activation function for the realization of the embodiment of the fully integrated COIN Co-processor to be built in the future.
by Wegene Haile Tadele.
M. Eng.

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29

Sridhar, Deepak. "Oxygen Carrier Development and Integrated Process Demonstration for Chemical Looping Gasification Systems." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1338322340.

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30

Li, Fei. "Modelling and optimisation of post-combustion carbon capture process integrated with coal-fired power plant using computational intelligence techniques." Thesis, University of Newcastle upon Tyne, 2018. http://hdl.handle.net/10443/4013.

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Coal-fired power plants are the major source of CO2 emission which contributes significantly to global climate change. An effective way to reduce CO2 emission in coal-fired power plants is post-combustion carbon dioxide (CO2) capture (PCC) with chemical absorption. The aim of this project is to carry out some research in model development, process analysis, controller design and process optimization for reliable, optimal design and control of coal-fired supercritical power plant integrated with post-combustion carbon capture plant. In this thesis, three different advanced neural network models are developed: bootstrap aggregated neural networks (BANNs) model, bootstrap aggregated extreme learning machine (BAELM) model and deep belief networks (DBN) model. The bootstrap aggregated model can offer more accurate predictions than a single neural network, as well as provide model prediction confidence bounds. However, both BANNs and BAELM have a shallow architecture, which is limited to represent complex, highly-varying relationship and easy to converge to local optima. To resolve the problem, the DBN model is proposed. The unsupervised training procedure is helpful to get the optimal solution of supervised training. The purpose of developing neural network models is to find a best model which can be used in the optimization of the CO2 capture process precisely. This thesis also presents a comparison of centralized and decentralized control structures for post-combustion CO2 capture plant with chemical absorption. As for centralized configuration, a dynamic multivariate model predictive control (MPC) technique is used to control the post-combustion CO2 capture plant attached to a coal-fired power plant. When consider the decentralized control structures based on multi-loop proportional-integral-derivative (PID) controllers, two different control schemes are designed using relative disturbance gain (RDG) analysis and dynamic relative gain array (DRGA) analysis, respectively. By comparing the two control structures, the MPC structure performs better in terms of closed-loop settling time, integral squared error, and disturbance injection.

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van, Der Meer Willem Arie. "A thermofluid network-based methodology for integrated simulation of heat transfer and combustion in a pulverized coal-fired furnace." Doctoral thesis, Faculty of Engineering and the Built Environment, 2021. http://hdl.handle.net/11427/33045.

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Coal-fired power plant boilers consist of several complex subsystems that all need to work together to ensure plant availability, efficiency and safety, while limiting emissions. Analysing this multi-objective problem requires a thermofluid process model that can simulate the water/steam cycle and the coal/air/flue gas cycle for steady-state and dynamic operational scenarios, in an integrated manner. The furnace flue gas side can be modelled using a suitable zero-dimensional model in a quasi-steady manner, but this will only provide an overall heat transfer rate and a single gas temperature. When more detail is required, CFD is the tool of choice. However, the solution times can be prohibitive. A need therefore exists for a computationally efficient model that captures the three-dimensional radiation effects, flue gas exit temperature profile, carbon burnout and O2 and CO2 concentrations, while integrated with the steam side process model for dynamic simulations. A thermofluid network-based methodology is proposed that combines the zonal method to model the radiation heat transfer in three dimensions with a one-dimensional burnout model for the heat generation, together with characteristic flow maps for the mass transfer. Direct exchange areas are calculated using a discrete numerical integration approximation together with a suitable smoothing technique. Models of Leckner and Yin are applied to determine the gas and particle radiation properties, respectively. For the heat sources the burnout model developed by the British Coal Utilisation Research Association is employed and the advection terms of the mass flow are accounted for by superimposing a mass flow map that is generated via an isothermal CFD solution. The model was first validated by comparing it with empirical data and other numerical models applied to the IFRF single-burner furnace. The full scale furnace model was then calibrated and validated via detailed CFD results for a wall-fired furnace operating at full load. The model was shown to scale well to other load conditions and real plant measurements. Consistent results were obtained for sensitivity studies involving coal quality, particle size distribution, furnace fouling and burner operating modes. The ability to do co-simulation with a steam-side process model in Flownex® was successfully demonstrated for steady-state and dynamic simulations.

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Clubbe, Richard. "Serine integrase-based 'landing pad' systems for chromosomal integrations of heterologous genes in Escherichia coli." Thesis, University of Glasgow, 2018. http://theses.gla.ac.uk/30585/.

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Due to its long history of industrial applications, extensively studied biology and rapid growth rates, Escherichia coli is an important cell factory for metabolic engineering and an increasingly popular chassis organism for synthetic biology. Serine integrases, which function naturally to incorporate bacteriophage DNA into the host genome, represent a powerful and flexible tool for the genomic integration of heterologous genes or pathways into host organisms. In the system described here, serine integrase enzymes are used to recombine two pairs of non-identical attachment sites, located on a chromosomally-integrated “landing pad” (LP) and an introduced “donor cassette”, resulting in cassette exchange of a transgene into a known locus on the E. coli genome. In this work, a landing pad was designed for φC31 integrase, consisting of two φC31 attB sites, both with differing central dinucleotide pairs, in a head-to-head orientation flanking an erythromycin resistance marker gene. This φC31 LP was inserted into the E. coli genome, replacing the non-essential pepA gene, by recombineering. Cassette exchange experiments were then performed, in which a temperature-sensitive plasmid carrying a donor cassette consisting of corresponding attP sites to the φC31 LP attB sites flanking an antibiotic resistance marker was transformed under the inducible expression of φC31 integrase. Serine integrases recombine their target sites in a highly unidirectional reaction. The reverse excision reaction, between integration product sites attL and attR, can only proceed with the addition of the integrase-associated recombinational directionality factor (RDF). Using in vitro recombination assays, TG1 integrase was shown to have very highly controlled directionality. Addition of the TG1 RDF gp25 strongly activates attL-attR recombination, taking recombination activity from a background level of 9% to 72% recombination of the substrate. TG1 gp25 also strongly inhibits attP-attB recombination, decreasing recombination from 77% to 8%. This demonstrates its potential as a highly controllable recombinase for synthetic biology. This work also investigated cross-reactivity of integrases and their non-cognate RDFs, showing that the TG1 RDF gp25 is able to activate φC31 integrase attL- attR recombination, however does not similarly inhibit φC31 attP-attB.

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33

Alam, Mohammad Masroor. "An integrated approach to dust control in coal mining face areas of a continuous miner and its computational fluid dynamics modeling /." Available to subscribers only, 2006. http://proquest.umi.com/pqdweb?did=1203573831&sid=2&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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34

Arya, Sampurna N. "INVESTIGATION OF THE EFFECTIVENESS OF AN INTEGRATED FLOODED-BED DUST SCRUBBER ON A LONGWALL SHEARER THROUGH LABORATORY TESTING AND CFD SIMULATION." UKnowledge, 2018. https://uknowledge.uky.edu/mng_etds/40.

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Dust generation at an underground coal mine working face continues to be a health and safety issue. Prolonged exposure to high concentrations of airborne respirable dust can cause a debilitating and often fatal respiratory disease called Black Lung. In addition, the deposition of float dust in mine return airways poses a serious safety hazard if not sufficiently diluted with inert rock dust. A localized methane explosion can transition into a self-propagating dust explosion. Since dust is a byproduct of various mining activities, such as cutting and loading, crushing, and transportation, the dust-related issues cannot be totally eliminated. However, the adverse health effects and safety concerns can be minimized if a significant amount of the generated dust is removed from the ventilation air by a mechanical device, such as a dust scrubber. Over the last three decades, flooded-bed dust scrubbers integrated into continuous miners have been successfully applied for capturing and removing airborne dust generated at the working face. According to the National Institute for Occupational Safety and Health (NIOSH), a flooded-bed scrubber can achieve more than 90% capture and cleaning efficiencies under optimum conditions. Although flooded-bed scrubbers have proven useful in the vast majority of cases, they have not yet been successfully applied to a longwall face. In the United States, numerous attempts have been made to reduce dust concentration at a longwall face through the application of a scrubber; but, none were successfully implemented. Encouraged by the successful use of a flooded-bed scrubber system at continuous miner faces, this research revisits the flooded-bed scrubber concept for a longwall shearer. For this investigation, a full-scale physical model of a Joy 7LS longwall shearer, modified with an integrated flooded-bed dust scrubber, was designed and fabricated at the University of Kentucky. The scope of work for this research was limited to capturing and cleaning dust generated near the shearer headgate drum only. The mock-up was transported to, and assembled in, the full-scale longwall dust gallery at the NIOSH Pittsburgh Research Laboratory (PRL). Tests were conducted to examine: (1) the effect of the scrubber on headgate-drum dust reduction and (2) the combined effect of the scrubber and splitter sprays on headgate drum dust reduction. Analysis of test results for the scrubber-alone condition indicates a significant dust reduction of up to 57% in the return airway and 85% in the test gallery walkway, whereas the combination of scrubber and splitter-arm sprays shows dust reduction of up to 61% and 96% in the return and walkway, respectively. These results indicate that a flooded-bed scrubber integrated into a longwall shearer can be used as a viable technique to reduce a large portion of airborne dust at a longwall face. Subsequently, a Computational Fluid Dynamics (CFD) model of the longwall gallery and shearer was developed and validated using the results of the experimental study. The CFD simulation results are in good agreement with the experimental results with a maximum of 9.7% variation. This validated CFD model can be used in future research to predict the effects of modifications to the scrubber system, including modifications to the scrubber inlet, to optimize the scrubber design, and to evaluate the effectiveness of adding a tailgate drum dust scrubber.

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35

Haneburger, Ina Maria Suntka [Verfasser], and Kirsten [Akademischer Betreuer] Jung. "Insights into the molecular signal perception mechanism of the membrane-integrated transcriptional activator CadC of Escherichia coli / Ina Maria Suntka Haneburger. Betreuer: Kirsten Jung." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2011. http://d-nb.info/1041224400/34.

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36

Olaleye, Akeem Kehinde. "Modelling and operational analysis of coal-fired supercritical power plant integrated with post-combustion carbon capture based on chemical absorption under UK grid requirement." Thesis, University of Hull, 2015. http://hydra.hull.ac.uk/resources/hull:13227.

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Fossil-fuel fired power plants are subjected to stringent operational regime due to the influx of renewable resources and the CO2 emission reduction target. This study is aimed at modelling and analysis of supercritical coal-fired power plant (SCPP) integrated with post-combustion CO2 capture (PCC) and its response electricity grid demand constraints. Current status of dynamic modelling of SCPP integrated with PCC was reviewed to identify the gaps in knowledge. It was observed that no accurate dynamic model of an SCPP integrated with PCC had been reported in open literature. A steady state model of the SCPP integrated with PCC was developed with Aspen Plus®. The model was validated with the reference plant and it was found that the relative error is about 1.6%. The results of the conventional and advanced exergetic analysis showed that the energy/exergy consumption and the efficiency of the integrated system can be improved by recovering the avoidable exergy destruction in the whole system. Dynamic models of SCPP once-through boiler based on lumped parameter and distributed parameter approaches were compared. The distributed parameter model gave a more accurate prediction of the SCPP boiler dynamics at different load levels. Analysis of the strategies for operating the SCPP under the UK grid requirement as regards to primary frequency response was performed using the validated SCPP model. The results show that using turbine throttling approach, extraction stop or condensate stop individually was not sufficient to meet the grid requirement. A combination of turbine throttling, extraction stop and/or condensate stop can achieve a 10% increase in maximum continuous rating (MCR) of the power plant within 10 seconds to 30 seconds of primary frequency change as required by the UK grid. The dynamic model of SCPP was integrated with a validated and scaled-up model of PCC. Analysis of the strategies for operating the SCPP integrated with PCC under the UK grid requirement as regards to primary frequency response was undertaken. The results show that the stripper stop mechanism is not sufficient for the 10% MCR required for the primary response. The results show that the combination of stripper stop mechanism with extraction stop can meet the 10% MCR requirement for integrated plant operating at above 75% of its full capacity. The throttling and stripper stop configuration only barely meets the demand at full load capacity. The condensate stop combination with the stripper stop mechanism on the other hand could not meet the frequency response requirement at any load level.

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37

Krawczynski, Lukasz. "Sequence Stratigraphic Interpretation integrated with 3-D Seismic Attribute Analysis in an Intracratonic Setting: Toolachee Formation, Cooper Basin, Australia." Queensland University of Technology, 2004. http://eprints.qut.edu.au/16087/.

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This study integrates sequence stratigraphy of the Late Permian Toolachee Formation in the non-marine intracratonic Permian-Triassic Cooper Basin, Australia with 3-D seismic attribute analysis to predict the extent of depositional environments identified on wireline and well core data. The low resolution seismic data (tuning thickness 23 - 31 m) comprised of six seismic horizons allowed the successful testing of sequence stratigraphic interpretations of the productive Toolachee Formation that were based on wireline data. The analysis of 29 well logs and three 20 m core intervals resulted in the identification of eleven parasequences that comprise the building blocks of an overall transitional systems tract, characterised by a gradual increase in accommodation. The parasequences reflect cyclic transitions between braided and meandering fluvial systems as a result of fluctuations in sediment flux, possibly driven by Milankovitch climatic-forcing. The seismic horizon attribute maps image mostly the meandering fluvial bodies within the upper parts of the parasequences, but some maps image the lower amalgamated sand sheets and show no channel structures. Categorisation of the fluvial bodies in the overbank successions reflects a gradual decrease in sinuosity, channel width, and channel belt width up-section, supporting the overall increase in accommodation up-section. Similar acoustic impedance values for shales and sands do not suggest successful seismic forward modelling between the two lithologies. Geological interpretations suggest most imaged channel fill to be made up predominantly of fine sediments, as channel avulsion and abandonment is common and increases with time. Seismic forward modelling resulted in the interpretation of carbonaceous shale as a possible channel fill, supporting the geological interpretations. The three major identified fluvial styles; braided, meanders, and distributaries are potential targets for future exploration. Extensive sand sheets deposited from braided fluvial systems require structural traps for closure. Meandering and anastomosing channel systems represent excellent stratigraphic traps, such as the basal sands/gravels of laterally accreted point bars.

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Smith, Adam N. "Reduced Chemical Weed Control Options in Virginia for Corn and Turfgrass and Characterization of Sorghum halepense Expressing Multiple Resistance to Nicosulfuron and Glyphosate." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/56957.

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Sustainable weed control in managed agricultural systems requires the judicious use of multiple weed control tactics and prevents over-reliance on any one tactic. In this context, sustainable weed management plays a critical role in the mitigation of one of agriculture's most pressing problems- herbicide resistance. Research conducted in Virginia sought to explore the effects of integrating multiple weed management tactics in corn and cool-season turfgrass. Additionally, research was conducted to confirm nicosulfuron and glyphosate herbicide resistance in Virginia johnsongrass and elucidate the molecular mechanisms conferring those resistances. Rye and hairy vetch cover crop residues, combined with reduced rates of preemergence herbicide and postemergence glyphosate applications, were shown to provide sufficient weed control and corn yield. Cover crop type or residue level did not augment weed control in corn production systems, but the use of glyphosate was essential for late-season weed control. Rye and vetch biculture as a cover crop increased corn yield compared to rye cover crop alone. In cool-season turfgrass, the addition of reduced preemergence herbicide rates to corn gluten meal, an organic herbicide product, reduced crabgrass 25%. Moreover, control was dependent on herbicide choice. Herbicides applied at half of recommended labeled rates or less did not control crabgrass at a commercially-acceptable level, regardless of corn gluten meal addition. In field experiments, Virginia johnsongrass expressed resistance to nicosulfuron and glyphosate. Glyphosate at 0.88 kg ae ha-1 controlled johnsongrass 65%. Nicosulfuron at 0.14 kg ai ha-1 controlled the same population 10%. Greenhouse experiments confirmed differential sensitivity of putative herbicide-resistant johnsongrass seedlings to nicosulfuron and glyphosate when compared to a susceptible population. Herbicide resistance was not conferred via target-site mutation. Five ALS-gene site mutations were confirmed absent in Virginia johnsongrass, while three others were located in coding regions that could not be elucidated in johnsongrass. Further investigations showed glyphosate resistance was not conferred via reduction in herbicide absorption or translocation. The susceptible johnsongrass caused an increase in a polar metabolite at Rf = 0.17 with concomitant reduction in glyphosate over time. Although the mechanism is not clear, these data suggests that glyphosate resistance in johnsongrass may be associated with differential metabolism.
Ph. D.

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39

Long, Henry A. III. "Development and Thermodynamic Analysis of an Integrated Mild/Partial Gasification Combined Cycle (IMPGC) Under Green and Brown Field Conditions With and Without Carbon Capture." ScholarWorks@UNO, 2018. https://scholarworks.uno.edu/td/2538.

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Coal is a very prominent energy source in the world, but it is environmentally unattractive due to its high sulfur and ash content as well as its alleged contribution towards climate change, but it is affordable, abundant, and has high energy content. Thus, utilizing coal in a cleaner and more efficient way has become necessary. One promising clean coal technology involves fully gasifying coal into synthesis gas, cleaning it, and feeding it into a high-efficiency combined cycle, such as an Integrated Gasification Combined Cycle (IGCC). Inspired by the recent success of warn gas cleanup (WGCU), mild and partial gasification are proposed as less energy intensive options. This Integrated Mild/Partial Gasification Combined Cycle (IMPGC) could significantly save energy and improve efficiency. The objective of this study is to investigate the capabilities of IMPGC as both a new plant and a retrofit option for traditional coal power plants with and without carbon capture. I MPGC relies on the principles of mild and partial gasification and the recently available WGGU technology with the following benefits: a.) completely negate the need for syngas cooling; b.) significantly reduce the energy needed to fully thermally crack the volatiles and completely gasify the char as in the IGCC system; c.) preserve the high chemical energy hydro-carbon bonds within the feedstock to allow more efficient combustion in the gas turbine; d.) reduce the size of gasifier and piping to reduce the costs; and e.) enable retrofitting of an old coal power plant by preserving the existing equipment. The software used (Thermoflex®) was first validated with established cases from the U.S. Department of Energy. For new plants, the results show that IMPGC’s efficiency is 8 percentage points (20%) higher than IGCC, 8 points higher than a modern subcritical Rankine cycle, and 3-4 points higher than an ultra-supercritical (USC) cycle. When retrofitting older plants, a minimum improvement of over 4 points is predicted. When carbon capture is involved, IMPGC’s efficiency becomes 10 points better than a subcritical plant and 8 points better than a USC plant. Emissions wise, IMPGC is better than IGCC and much better than Rankine cycle plants.

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Rieger, Mathias. "Advanced modeling and simulation of integrated gasification combined cycle power plants with CO2-capture." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2014. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-150522.

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The objective of this thesis is to provide an extensive description of the correlations in some of the most crucial sub-processes for hard coal fired IGCC with carbon capture (CC-IGCC). For this purpose, process simulation models are developed for four industrial gasification processes, the CO-shift cycle, the acid gas removal unit, the sulfur recovery process, the gas turbine, the water-/steam cycle and the air separation unit (ASU). Process simulations clarify the influence of certain boundary conditions on plant operation, performance and economics. Based on that, a comparative benchmark of CC-IGCC concepts is conducted. Furthermore, the influence of integration between the gas turbine and the ASU is analyzed in detail. The generated findings are used to develop an advanced plant configuration with improved economics. Nevertheless, IGCC power plants with carbon capture are not found to be an economically efficient power generation technology at present day boundary conditions.

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Åberg, Anna. "New insights into the role of ppGpp and DksA through their effect on transcriptional regulation of housekeeping and colonization related genes of Escherichia coli /." Umeå : Univ, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1669.

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42

Basu, Piyali. "A novel whole system integrated genomics approach to identify key genetic components which facilitate synthetic design of a genetically engineered strain of Escherichia coli K12 with enhanced isobutanol tolerance." Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/13712.

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There has been an increased global interest in biofuels which provide a renewable and sustainable alternative to fossil fuels. Isobutanol is an attractive and superior alternative to the currently produced bioethanol possessing several key advantages. Previous work focuses on strategies for metabolic optimisation of carbon utilisation. However, existing solutions reach a stage where the amount of alcohol produced reaches toxic thresholds for bacteria. This inhibits growth and reduces carbohydrate consumption resulting in lower product yields rendering the biofuel production process uneconomical. In this project, a novel strategy has been adopted which uses a whole system integrated genomics approach consisting of expression profiling, selection to create isobutanol-adapted lineages, next generation sequencing, and comparative behavioural genomics to interrogate the system thoroughly and identify critical determinants of resistance to isobutanol. These were used in the highly-defined model species, E. coli K12 to deliver results of the adaptive mechanisms which take place across the entire genome. 41 gene candidates (4 previously identified in literature) were identified to play a role in isobutanol tolerance. These candidates belong to a range of functional groups such as carbohydrate metabolism, oxidative stress response, osmotic stress response; but also identified novel membrane-associated functions such as the Tol-Pal system, BAM complex and colanic acid production. The results also identify critical genes with unknown functions. The results support previous notions that central carbon metabolism shifts from aerobic to anaerobic metabolism in the presence of isobutanol, but also shows there is a transitionary phase where mixed acid fermentation pathways are utilised. This shift was previously thought to be mediated by the ArcA-ArcB two-component system. However, these results suggest the inactive 2Fe-2S core of the anaerobic-regulator Fnr is re-activated by Fe2+ to form the 4Fe-4S core transported by the FeoAB ferrous iron transport system. The strategy also identified the Tol-Pal system and show it is essential to grow in the presence of isobutanol, which is responsible for the maintaining the integrity of the cell envelope structure and increasing the rate of cell division. The BAM complex is responsible for folding and assembly of outer membrane proteins (OMP) and OMP membrane permeability- this system was found to be important for growth in isobutanol, and SurA, which is the primary OMP assembly pathway provided tolerance which was specific to isobutanol. Colanic acid, an extracellular polysaccharide is produced when the cell experiences stress, and provides protection by forming a physical barrier around the cell. The results show that the presence of colanic acid plays a large role in allowing E. coli to grow in presence of isobutanol, and its role becomes essential at critical concentrations. The results also show deletion of the negative regulator of the colanic acid gene cluster improves growth at critical and growth-inhibiting concentrations. When consolidated, these results facilitated knowledge-led based design and subsequently led to the identification of components for a synthetic design schedule, which lists the genetic manipulations proposed to exploit E. coli to enhance isobutanol tolerance.

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43

Couve-Deacon, Elodie. "Epidémiologie et régulation des intégrons de classe 1 chez Acinetobacter Baumannii." Thesis, Limoges, 2017. http://www.theses.fr/2017LIMO0116/document.

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Acinetobacter baumannii est un pathogène opportuniste qui prend une importance clinique croissante du fait de l’acquisition de multi-résistance. Nous avons étudié chez A. baumannii les caractéristiques et la régulation des intégrons de classe 1 (IM1) qui sont des systèmes génétiques favorisant l’acquisition, l’expression et la dissémination des gènes de résistance aux antibiotiques. Nous avons montré qu’il existe une prédominance des promoteurs des cassettes Pc fort in vivo dans une collection d’isolats cliniques et d’environnement hospitalier et in silico dans les IM1 chez A. baumannii. Nous avons aussi montré que l’expression des Pc chez A. baumannii est 4 fois plus faible que chez E. coli, quel que soit le variant de Pc. Deux explications sont possibles pour la sélection des Pc forts chez A. baumannii : (i) la nécessité d’avoir un niveau d’expression suffisant en clinique pour survivre à la pression de sélection antibiotique et (ii) la nécessité d’une régulation de l’expression de l’intégrase, représentant un coût biologique important. En effet, A. baumannii ne possède pas le système de répression par LexA existant chez E. coli. Nos résultats ouvrent le champ de l’étude de la régulation des IM1 chez A. baumannii et ainsi l’identification de nouvelles voies d’action pour lutter contre l’antibio-résistance
Acinetobacter baumannii is an opportunistic pathogen of increasing clinical importance due to the acquisition of multi-resistance. We studied in A. baumannii the characteristics and regulation of class 1 integrons (IM1), which are genetic systems that favor the acquisition, expression and dissemination of antibiotic resistance genes. We have shown that there is a predominance of strong Pc cassette promoters, in vivo, in a collection of clinical and hospital environment isolates, and in silico, from A. baumannii IM1 published in NCBI. We have also shown that the expression of Pc in A. baumannii is 4-fold lower than in E. coli, regardless of the Pc variant. Explanations that can be raised for the selection of strong Pc in A. baumannii are: (i) the need for a sufficient level of antibiotic resistance expression to survive the selection pressure in clinical environment; and (ii) the need for regulation of the integrase expression, which is of significant biological cost. Indeed A. baumannii does not have the LexA repression system existing in E. coli. Our results open the field of the study of IM1 regulation in A. baumannii and thus the identification of new pathways to fight antibiotic resistance

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44

Kvasnička, Tomáš. "Informační systémy v oblasti ekologie." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-124736.

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This thesis compares the environmental information systems and the providing of environmental information from the government institutions. The objective of this work is to analyze current information systems under the Integrated environmental information system (JISZP) and verify the hypothesis that all these information systems are integrated. The further goal is to prove whether or not the Act No. 123/1998 is fulfilled in practice. The first part contains an analysis of JISZP systems according to various criteria. The second part maps the legislation of information providing and verifies the compliance with the Law No. 123/1998. The final part contains an evaluation and recommendations for further action.

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45

Fränzel, Benjamin [Verfasser], Dirk [Gutachter] Wolters, and Christian [Gutachter] Herrmann. "Integrale Membranproteine im Fokus quantitativer Proteomforschung für medizinische Anwendungen und biotechnologische Fragestellungen am Beispiel von Corynebacterium glutamicum und Escherichia coli / Benjamin Fränzel ; Gutachter: Dirk Wolters, Christian Herrmann ; Fakultät für Chemie und Biochemie." Bochum : Ruhr-Universität Bochum, 2010. http://d-nb.info/1211174077/34.

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46

Johansson, Carolina. "Mechanisms and DNA Specificity in Site-specific Recombination of Integron Cassettes." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl [distributör], 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7429.

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47

Lee, Po-Chien, and 李波前. "Integrated design and control of linear amplifier and voice coil motor." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/45326301124924823646.

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碩士
正修科技大學
機電工程研究所
97
Precision positioning has been played a very important role in industry applications. However, when the positioning accurate is highly demanded, the nonlinear characteristic of transmission mechanism, such as backlash, friction and hysteresis, will induce many difficult control issues. Therefore, this thesis proposes one-dimensional linear actuator design by integrating voice coil motor and flexure mechanism, to eliminate the phenomenon that high-precision positioning system must face to the nonlinearity.Based on to dsPIC 16-bit signal processor, this thesis also develops an intelligent digital linear motor drive, which is the integration design of single-chip set, PWM power electronic circuit, CANbus interface circuit, current/voltage interface circuit and so on. Using the technique of real-time network control, the proposed linear actuator can reduce the complexity of multi-axis motion application. Finally, a PID controller design is provided according to the pole-placement technique. Positioning of the proposed integrated mechanism design and control scheme is effectively verified by the experimental results through the application of MATLAB/Simulink/Real-Time Windows Target.

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48

Fernandes, Filipa Rodrigues Filipe. "Development of an Ignition Coil Integrated System to Monitor the Spark Plugs Wear." Master's thesis, 2016. http://hdl.handle.net/10362/85394.

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Automotive industry is undergoing significant changes to answer new emission limits and cost restrictions. These lead to unfavourable operating conditions for the components (including spark plugs and ignition coils): overheating, higher pressures, downsizing and leaner air/fuel mixtures. Consequently, the ignition coil integrated system is being asked for stronger and multiple sparks and longer burning times. In response, rare precious metals (iridium, platinum, tungsten) must be utilized, resulting in a cost increase thereof. Hence, it is a main interest to monitor these high quality components. In this work, Paschen Law is used to find a relation between the electrodes gap (ultimately related to wear conditions) and breakdown voltage. Thereby, this thesis is mainly focused on developing a method to monitor the referred voltage. In a transistor-ized coil ignition (TCI) system, the microcontroller can measure a time which is directly proportional to the breakdown voltage. That information is collected coil-internally and communicated to the ECU. The latter carries out statistical data analysis along with re-al-time pressure, load and speed data. After laboratory and car tests, it was proved that the secondary current sensing circuit may also serve as a breakdown voltage sensor, eliminating the need for any cost increase rather than development costs concerning mass production of ignition coils.

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Ding, Hong-wei, and 丁泓瑋. "Design of Rogowski Coil Integrator for Welding Current Measurements." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/96841950216759410961.

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碩士
逢甲大學
自動控制工程學系
101
The key technology in developing the on-line quality monitoring system for resistance welding is the Rogowski coil for measuring the welding current. Rogowski coil is constituted by the coil body and the integrator. This study assumes using a commercially available Rogowski coil body and attempts to design an integrator for the coil body in order to measure the welding current for three kinds of resistance welding power supplies: AC type, capacitive discharge type and DC inverter type. Firstly, the influence of the Rogowski coil frequency response on measuring the welding current and in designing the integrator is studied. If the Rogowski coil has large enough bandwidth, then the integrator can be designed without regarding the Rogowski coil frequency response. The suitability of passive RC integrator, active integrator and compound integrator is investigated. It is found that the passive RC integrator is an imperfect integrator in low frequency region and the active integrator has limited input voltage level in its operational amplifier. Therefore, a single RC integrator or a single active integrator cannot be applied. A compound integrator is designed by combining a RC integrator and an active integrator in series. However, the performance of the compound integrator depends on the exact matching of the parameters of the passive RC integrator and the active integrator. The aforementioned problem will be analyzed and verified through simulation and experiments.

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50

Wu, Jie. "Inductive links with integrated receiving coils for mems and implantable applications." 2003. http://etd.nd.edu/ETD-db/theses/available/etd-09302003-162720/.

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Thesis (Ph. D.)--University of Notre Dame, 2003.
Thesis directed by Gary H. Bernstein for the Department of Electrical Engineering. "September 2003." Includes bibliographical references (leaves 196-213).

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