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Big prisons : a study for the effects of the Israeli wall on Ni’lin village, in comparison with the effects of Berlin wall on Leipzig through Human Rights perspectiveKamhaui, Nida January 2009 (has links)
<p>George Gregory wrote in his book ‘The Colonial Presents’ in defining the Post colonialism; since the last decades of the 20th century, Andreas Huyssen suggested that the ‘present future to present pasts’ became the post-colonialism, which is a whole commitment to a future that is free from colonial power, and the growth in the disposition is part of the criticism of continuity between the colonial past and present colonial rule. But they almost denied the capacities that belong to the colonial past are confirmed and activated again in the colonial present. And this is appearing in many histories of the colonialism, but post-colonialism came to distinguish from these projects or histories by the tight relation between culture and power.</p><p>Building up Apartheid walls is a result to the colonial and Post colonial projects. As wall entered the political concept, we can see many built Apartheid walls through history.</p><p>The Essay’s main aim is to study two selective walls; the Israeli wall in Palestine and Berlin wall, from human rights perspective, which can let readers to have fair information about those two walls, and their effects on people’s lives that live or lived beside those walls.</p><p>A discussion will follow the illustrated information which I took them from many references which include direct information about those two walls.</p><p>My results are that these two Apartheid walls affect and undermine people’s rights who are living beside and around those walls.</p>
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Cellulose biosynthesis inhibitors modulate defense transcripts and regulate genes that are implicated in cell wall re-structuring in arabidopsisMortaji, Zahra 01 June 2011 (has links)
The cell wall is a multifunctional structure which is implicated in plant growth and development as well as responding to any environmental changes including biotic and abiotic stresses. One of the practical approaches in cell wall integrity studies is the modification of the quality and quantity of particular cell wall components or destroying the specific step in cell wall synthesis pathway using Cellulose Biosynthesis Inhibitors (CBIs). In this case, chemical screen for swollen organ phenotype has proved to be an important technique to identify the genes that are directly or indirectly involved in cellulose biosynthesis.
In the present research, a number of synthetic CBIs were obtained through a chemical library screen from Chembridge Company for the root swollen phenotype which is believed to be the response to a defect in cellulose biosynthesis. Therefore, a genome-wide expression profiling based on Affymetrix ATH1 GeneChip arrays (contains 22810 probe sets) were applied to investigate the altered transcriptome of four different CBIs including CBI-15, 18, 22, and 27 and isoxaben in 5 day-old Arabidopsis thaliana seedlings. The results of this project revealed overlapped up and down-regulated genes as well as discriminate responses to each CBI. The most striking modification were found in genes involve in response to the stress as well as cell wall integrity and restructuring. Thus, the identification of regulated genes under CBIs treatment suggests a robust candidate group of genes that likely to be correlated to cell wall biosynthesis. / UOIT
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The <i>Aspergillus nidulans</i> Galf biosynthesis pathway is a promising drug targetEl-Ganiny, Amira Mohamed Mohamed Ali 09 June 2011
Human systemic fungal infections are increasing, and causing high morbidity and mortality. Treatment is challenging because fungi share many metabolic pathways with mammals. Current antifungals are losing effectiveness due to drug resistance. In immunocompromised patients Aspergillus fumigatus causes systemic aspergillosis, the most important airborne fungal disease. Mortality from aspergillosis exceeds 50% even with aggressive treatment. We need novel antifungal drug targets. Fungal cell wall components are promising targets for antifungal therapy as they are essential for fungi and absent from humans.
The sugar galactofuranose (Galf) is a 5-memberd ring form of galactose that is found in the cell walls of many fungi, but not in mammals. I used molecular biology and microscopy techniques to characterize Galf biosynthesis enzymes in the model species A. nidulans. I studied three enzymes that catalyze sequential steps in Galf biosynthesis: UgmA, UgtA and UgeA. UDP-galactopyranose mutase (UgmA) creates UDP-galactofuranose (UDP-Galf) from UDP galactopyranose (UDP-Galp) in the cytoplasm. The UDP-Galf transporter (UgtA) moves UDP Galf into membrane bound organelles for incorporation into cell wall compartments. Upstream of UgmA, UDP-glucose/galactose epimerase (UgeA) interconverts UDP-glucose into UDP-Galp, the UgmA substrate. Neither UgmA nor UgtA has a human counterpart; UgeA is in the Leloir galactose metabolism pathway that found in many organisms from bacteria to humans.
None of UgeA, UgmA and UgtA is essential for viability of A. nidulans, but deleting any one of them substantially reduces colony growth and sporulation (Figure i). Wild type and Galf defective strains (ugeA∆, ugmA∆ and ugtA∆) were quantified for colony growth, cell morphometry, spore formation and germination, as well as wall architecture. The abundance of these proteins was regulated using the alcA promoter. Galf content was assessed by immunolocalization in the Galf defective strains, showing that those strains lacked immunodetectable Galf. Gene products were localized with fluorescent protein tags; both UgmA and UgeA were cytoplasmic, whereas UgtA was Golgi localized. Wall surfaces were imaged and force-probed using transmission electron microscopy and atomic force microscopy. Overall, Galf deletion strains had aberrant wall maturation, and poorly consolidated surfaces. Our results indicate that Galf is necessary for abundant sporulation, wild type growth and full maturation of Aspergillus cell wall.
Galf deletion strains were assessed for sensitivity to antifungal agents in clinical use. They were significantly more sensitive to caspofungin and amphotericin B that target cell wall synthesis and cell membrane chemistry, respectively. Thus, anti-Galf drugs (once created) may be useful in combination with existing antifungal drugs. In summary, Galf biosynthesis pathway appears to be promising as an antifungal drug development target.
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Design Guidelines for Test Level 3 (TL-3) Through Test Level 5 (TL-5) Roadside Barrier Systems Placed on Mechanically Stabilized Earth (MSE) Retaining WallSaez Barrios, Deeyvid 1980- 14 March 2013 (has links)
The use of Mechanically Stabilized Earth (MSE) wall structures has increased dramatically in recent years. Traffic barriers are frequently placed on top of the MSE wall to resist vehicular impact loads. The barrier systems are anchored to the concrete in case of rigid pavement. Nevertheless, in case of flexible pavement, the barriers are constructed in an L shape so that the impact load on the vertical part of the L can be resisted by the inertia force required to uplift the horizontal part of the L. The barrier must be designed to resist the full dynamic load but the size of the horizontal part of the L (moment slab) is determined using an equivalent static load.
Current design practice of barriers mounted on top of MSE retaining wall is well defined for passenger cars and light trucks. However, the information of this impact level is extrapolated to heavy vehicle impact. Therefore, the bases of this research is to develop design procedure and to help understand the dynamic behavior of a barrier-moment slab system on top of an MSE wall when subjected to heavy vehicle impact loads.
In a first part, numerical analyses were conducted to better understand the behavior of the barrier-moment slab system when subjected to heavy vehicle impact loads. The full-scale impact simulations were used to develop the recommendation for designing and sizing the barrier-moment slab system.
In a second part, the barrier-moment slab systems defined to contain heavy vehicle impact loads were placed on top of an MSE wall model to study the kinematic behavior of the system. Loads in the soil reinforcing strips and displacements on the barriers and wall components are evaluated to define recommendation for design of strip reinforcements against pullout and yielding.
In a third part, a full-scale crash test on a barrier-moment slab system on top of an instrumented 9.8 ft. (3 m) high MSE wall is described and analyzed. The MSE wall and barrier system were adequate to contain and redirected the vehicle and, therefore, it served as verification of the proposed recommendation.
Finally, conclusions are drawn on the basis of the information presented herein.
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Cortical microtubules and physical properties of cellulose microfibrils during primary cell wall formation in Arabidopsis thalianaFujita, Miki 05 1900 (has links)
Growth anisotropy, in which cells grow predominantly in one direction, is common in plant cells, and an essential event for plant form and function. The direction and degree of growth anisotropy are governed by the mechanical properties of the primary cell wall. When aligned in a parallel manner, cellulose microfibrils accommodate great resistance in the direction of their alignment to expansion driven by isotropic turgor pressure. Using the Arabidopsis thaliana inflorescence stem as a model system, field emission scanning electron microscopy (FESEM) analysis demonstrated that the establishment of parallel arrangement of microfibrils is closely correlated with anisotropic cell expansion. In the novel anisotropy 1 (any1) mutant allele of the primary cellulose synthase CesA1, growth defects were correlated with random cellulose microfibril patterns in some inflorescence stem tissues.
Microtubules have been considered to be the most likely candidates for controlling the orientation of cellulose microfibrils. Recent studies have indeed demonstrated a close association of the plasma membrane-localized cellulose-synthase-complexes (CSCs) that produce cellulose and cortical microtubules. Despite this close association, microtubule disruption did not cause cellulose microfibrils to lose parallel alignment in the radial and inner periclinal walls of cells in the inflorescence stem, suggesting that microtubules influence mechanical properties of cellulose microfibrils other than orientation. X-ray diffraction analysis demonstrated that cellulose crystallinity in wild-type plants declines at the growth-promoting temperature of 29°C, whereas crystallinity fails to adapt and remains high in mor1-1, the temperature-sensitive mutant whose microtubule arrays become disorganized at its restrictive temperature (29°C). This finding suggests that organized microtubules are involved in reducing cellulose crystallinity that normally accompanies increased cell expansion.
Live-cell imaging of CSCs by tracking a yellow fluorescent protein (YFP)-tagged CesA6 subunit in hypocotyl cells demonstrated that dynamic and well-organized microtubules affect the velocity, the direction of movement, and the density of CSCs, suggesting that there is a close relationship between microtubules and CSCs. Together with the finding that microtubules also control the distribution of COBRA, a GPI-anchored wall protein that is essential for growth anisotropy, I discuss the variety of roles microtubules play in anisotropic growth.
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Catalysts for steam reforming of Ethanol in a catalytic wall reactorTorres Rivero, José Antonio 22 February 2008 (has links)
La energía se ha convertido en una necesidad vital para garantizar el desarrollo de las sociedades modernas. Entre las diferentes posibles alternativas para producir energía, el hidrogeno presenta varias características que lo convierten en un atractivo vector energético: primero, se trata de una tecnología más eficiente para transformar la energía química en electricidad -por ejemplo, utilizando pilas de-combustible, las cuales también reducen de manera significativa los niveles de emisión de CO2 -; en segundo lugar, el hidrogeno puede ser producido a partir de una amplia variedad de materias primas, incluyendo recursos renovables y no renovables. Sin embargo, las tecnologías para producir hidrogeno para applicaciones con pilas de combustible aun requieren de un esfuerzo en investigación y desarrollo.El objetivo principal de esta tesis fue de evaluar técnicamente las opciones para preparar y utilizar catalizadores en placas insertados en un reactor de pared catalítica para producir hidrogeno mediante el reformado por vapor de etanol bajo condiciones de alta eficiencia térmica. Para completar el objetivo general y los objetivos específicos, se diseño un plan experimental sistemático, compuesto de tres partes: documentación, experimentación y simulación numérica. La información utilizada se puede clasificar en tres ramas: primero, una revisión detallada de las características generales que presentan las técnicas de reformado, seguido por una revisión descriptiva del reformado por vapor de etanol, enfocado en los principales aspectos de la preparación de catalizadores y la realización de la reacción química. A continuación en segundo lugar, se presenta una descripción acerca de reactores estructurados y los métodos para preparar catalizadores. Por último, en tercer lugar, se expone una explicación centrada en los materiales, equipos y métodos empleados para explorar el rendimiento de los catalizadores. Esta parte incluye la descripción de: algunas de las técnicas analíticas más comunes para caracterizar y evaluar tanto catalizadores como compuestos químicos y la descripción de las herramientas utilizadas en la simulación numérica.El primer bloque de simulación numérica tiene como fin evaluar las posibles restricciones termodinámicas por medio de análisis específicos basados en el equilibrio termodinámico, tanto del reactor como del proceso integrado. Luego, se ejecuta un mapeo del conjunto de condiciones operacionales, compuesto por cuatro variables principales: (temperatura, relación vapor carbón, presión y factor de recobro de hidrogeno en el separador de membrana). Ello con el fin de garantizar una operación auto-térmica del procesador de combustible. Se compara la habilidad y la ventaja entre los diferentes tipos de catalizadores publicados en trabajos previos en base a las condiciones termodinámicas ideales determinadas en el análisis termodinámico.Para los catalizadores en polvo, se realizo experimentos de caracterización y reacción mediante el empleo de un reactor de lecho fijo. Se ha efectuado un estudio sistematico para comparar la actividad y la selectividad de dos tipos de catalizadores, bajo condiciones moderadas de temperatura y relación vapor carbón. Los catalizadores basados en níquel (Ni/La2O3-Al2O3) y cobalto (Co-Fe/ZnO y Co-Mn/ZnO) han sido preparados y probados a las siguientes condiciones: temperatura en el rango de 400-500°C, relación vapor carbono entre 2 y 4, tiempo de contacto desde 4.3 hasta 1100 min·gcat molEtOH-1, cubriendo un rango de conversión de etanol desde 20 hasta 100%. Se ha efectuado un diseño de análisis multifactorial para establecer la influencia de las variables (temperatura, relación vapor carbón, tiempo de contacto y formulación del catalizador) en términos de la conversión de etanol y la selectividad hacia los diferentes productos.Por último, se ha efectuado la caracterización, simulación y experimentación utilizando una configuración de reactor de pared catalítica. Primero, se emplea un modelo en 2D para analizar las características principales del reactor de pared catalítica diseñado y construido para realizar la reacción sobre las placas con catalizador previamente preparadas. En segundo lugar, se expone de manera detallada el método seguido para preparar dos tipos diferentes de placas catalíticas. Estas placas con catalizador son caracterizadas de manera similar al método empleado con los catalizadores en polvo. Luego, se ha realizado un estudio sistemático para comparar la actividad y la selectividad de los dos tipos de placas catalíticas. Por último, mediante un modelo 1D se revelan aspectos fundamentales de la configuración del reactor de pared catalítica utilizando una configuración con dos canales paralelos, en los cuales se ejecutan una reacción endotérmica y otra exotérmica respectivamente.La principal conclusión de este trabajo es que el reformado por vapor de etanol puede ser realizado bajo condiciones de alta eficiencia térmica si se emplea un diseño basado en un reactor de pared catalítica con recobro de calor integrado a una unidad de separación para la purificación del hidrogeno. Las placas catalíticas han demostrado ser un elemento fundamental en este tipo de reactor porque incrementan de manera significativa el transporte de calor que se requiere para sostener las reacciones endotérmicas. / Energy has become a fundamental necessity to guarantee modern society development. Among different alternatives possible to produce energy, hydrogen presents several characteristics which make it an attractive energy vector: first, more efficient processes to transform chemical energy into electricity -such as Fuel Cells that, in addition, will help to reduce significantly CO2 emission levels-; and second, hydrogen can be produced from a large variety of feed stocks, including fossil and renewable resources. However, as hydrogen production technologies for Fuel Cell applications are not available commercially yet, it still requires additional R&D efforts.The principal objective of this thesis was to evaluate technical feasibility for preparing and using catalytic plates in a Catalytic Wall Reactor configuration to produce hydrogen by Steam Reforming of Ethanol under conditions of high thermal efficiency. To fulfill the overall and specific objectives, a systematic experimental plan was designed and executed. It was composed of three main parts: documentation, experimentation and numerical simulation. Background information is divided into three branches, first a detailed overview of technical features for reforming technology, followed by a descriptive review of Steam Reforming of Ethanol key aspects for catalysts preparation and reaction performance. Third is presented a comprehensive examination on structured reactor and catalyst preparation methods. In this part is exposed a detailed explanation of materials, equipments, and methods employed for screening catalyst and evaluating catalytic reactor performance. Also, is presented employed techniques for catalyst characterization and fluid analysis. Finally are described tools for numerical simulation.First component of numerical simulations evaluates possible thermodynamic constrains through specific analyses based on thermodynamic equilibrium of reactor and integrated fuel processor. Then, is performed a mapping for the set of four operational variables (temperature, steam to carbon ratio, pressure, and hydrogen recovery in the membrane separator), that allow an auto-thermal operation of the fuel processor. The suitability and advantages of the different catalysts preparations that are known from recent publications are discussed on the basis of the operation conditions determined on the thermodynamic analysis.Experimental work is performed for powder catalyst characterization and catalytic experimentation using a Packed Bed Reactor (PBR). It has conducted a systematic study to compare the activity and selectivity of two types of catalyst at moderate temperature and steam to carbon (SC) ratios. Nickel-based catalysts (Ni/La2O3-Al2O3) and novel Co-based catalysts (Co-Fe/ZnO and Co-Mn/ZnO) have been prepared and tested at temperatures of 400 and 500 °C, Steam to Carbon (SC) molar ratios of 2 and 4, and contact times from 4.3 to 1100 min·gcat molEtOH-1, covering a range of ethanol conversion from 20 to 100%. A multifactorial design analysis has been conducted to establish the significance of temperature, SC ratio, contact time and catalyst formulation on ethanol conversion and selectivity towards the different reaction products.At last, it is carried out the catalytic plate characterization, simulation and experimentation using a Catalytic Wall Reactor configuration. First, is used a 2D modeling to analyze main characteristics of the Catalytic Wall Reactor designed and constructed to perform reactions on the prepared catalytic plates. Prepared catalytic plates are characterize in a similar way to that employed for the powder catalysts. After that, it was conducted a systematic study to compare the activity and selectivity of two types of catalytic plates. 1D model reveals main aspects on thermal performance for a theoretical Catalytic Wall Reactor using two co-current channels with endothermic and exothermic reactions respectively.Main conclusion from this work is that Steam Reforming of Ethanol can be performed at high thermal efficiency if the design of the fuel processor is based on structured catalytic wall reactors with integrated heat recovery coupled to a separation unit for hydrogen purification. Catalytic plates have proven to be a key component on CWR because improves significantly the heat transfer which is required to sustain endothermic reactions.
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The <i>Aspergillus nidulans</i> Galf biosynthesis pathway is a promising drug targetEl-Ganiny, Amira Mohamed Mohamed Ali 09 June 2011 (has links)
Human systemic fungal infections are increasing, and causing high morbidity and mortality. Treatment is challenging because fungi share many metabolic pathways with mammals. Current antifungals are losing effectiveness due to drug resistance. In immunocompromised patients Aspergillus fumigatus causes systemic aspergillosis, the most important airborne fungal disease. Mortality from aspergillosis exceeds 50% even with aggressive treatment. We need novel antifungal drug targets. Fungal cell wall components are promising targets for antifungal therapy as they are essential for fungi and absent from humans.
The sugar galactofuranose (Galf) is a 5-memberd ring form of galactose that is found in the cell walls of many fungi, but not in mammals. I used molecular biology and microscopy techniques to characterize Galf biosynthesis enzymes in the model species A. nidulans. I studied three enzymes that catalyze sequential steps in Galf biosynthesis: UgmA, UgtA and UgeA. UDP-galactopyranose mutase (UgmA) creates UDP-galactofuranose (UDP-Galf) from UDP galactopyranose (UDP-Galp) in the cytoplasm. The UDP-Galf transporter (UgtA) moves UDP Galf into membrane bound organelles for incorporation into cell wall compartments. Upstream of UgmA, UDP-glucose/galactose epimerase (UgeA) interconverts UDP-glucose into UDP-Galp, the UgmA substrate. Neither UgmA nor UgtA has a human counterpart; UgeA is in the Leloir galactose metabolism pathway that found in many organisms from bacteria to humans.
None of UgeA, UgmA and UgtA is essential for viability of A. nidulans, but deleting any one of them substantially reduces colony growth and sporulation (Figure i). Wild type and Galf defective strains (ugeA∆, ugmA∆ and ugtA∆) were quantified for colony growth, cell morphometry, spore formation and germination, as well as wall architecture. The abundance of these proteins was regulated using the alcA promoter. Galf content was assessed by immunolocalization in the Galf defective strains, showing that those strains lacked immunodetectable Galf. Gene products were localized with fluorescent protein tags; both UgmA and UgeA were cytoplasmic, whereas UgtA was Golgi localized. Wall surfaces were imaged and force-probed using transmission electron microscopy and atomic force microscopy. Overall, Galf deletion strains had aberrant wall maturation, and poorly consolidated surfaces. Our results indicate that Galf is necessary for abundant sporulation, wild type growth and full maturation of Aspergillus cell wall.
Galf deletion strains were assessed for sensitivity to antifungal agents in clinical use. They were significantly more sensitive to caspofungin and amphotericin B that target cell wall synthesis and cell membrane chemistry, respectively. Thus, anti-Galf drugs (once created) may be useful in combination with existing antifungal drugs. In summary, Galf biosynthesis pathway appears to be promising as an antifungal drug development target.
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Capillary fiber mode energy distribution and the conditions of excitationLu, Hong-Jie 31 July 2011 (has links)
Purpose of this research is that capillary optic fiber transmission and energy distribution of internal energy.
Contains only single from the initial silica capillary fiber energy transfer within the simulation, and then changing the different input conditions (different incident angles, multi- mode and single mode) optical observation of the capillary wall modes and modal distribution between hole mode. Mode simulation, containing only the capillary in the simple addition of a layer of high-dielectric fiber optic ring to change its transmission mechanism, by analog control of its high dielectric ring geometry (thickness) of air holes the size of its hole mode can simulate the type of transmission mode number. By single-and double- layer energy transfer capillary mode simulation and modal changes in different input conditions, and further understanding of the capillary mode fiber transmission characteristics.
Combining the concept of adding fiber coupler and single-mode optical fiber capillary to produce a new original, and then by capillary tube method to make thick plugs can be more convenient and rapid production of a new type of coupler components.
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Thermal study of vulnerable atherosclerotic plaqueKim, Taehong 15 May 2009 (has links)
Atherosclerotic plaques with high probability of rupture show the presence of
a hot spot due to the accumulation of inflammatory cells. This study utilizes two
and three dimensional (2-D and 3-D) arterial geometries containing an atherosclerotic
plaque experiencing different levels of inflammation and uses models of heat transfer
analysis to determine the temperature distribution in the plaque region.
The 2-D studies consider three different vessel geometries: a stenotic straight
artery, a bending artery and an arterial bifurcation which model a human aorta, a
coronary artery and a carotid bifurcation, respectively. The 3-D model considers
a stenotic straight artery using realistic and simplified geometries. Three different
blood flow cases are considered: steady-state, transient state and blood flow reduction.
In the 3-D model, thermal stress produced by local inflammation is estimated
to determine the effect of inflammation over plaque stability. For fluid flow and
heat transfer analysis, Navier-Stokes equations and energy equation are solved; for
structural analysis, the governing equations are expressed in terms of equilibrium
equation, constitutive equation, and compatibility condition, which are are solved
using the multi-physics software COMSOL 3.3 (COMSOL, Inc.).
Our results indicate that the best location to measure plaque temperature in
the presence of blood flow is recommended between the middle and the far edge of
the plaque. The blood flow reduction leads to a non-uniform temperature increase
ranged from 0.1 to 0.25 oC in the plaque/lumen interface. In 3-D realistic model, the multiple measuring points must be considered to decrease the potential error in
temperature measurement even within 1 or 2 mm at centerline region of plaque. The
most highly thermal stressed regions with the value of 1.45 Pa are observed at the
corners of lipid core and the plaque/lumen interface.
The mathematical model developed provides a tool to analyze the factors affecting
heat transfer at the plaque surface. The results may contribute to the understanding
of the relationship between plaque temperature and the likelihood of rupture,
and also provide a tool to better understand arterial wall temperature measurements
obtained with novel catheters.
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Investigation of high-frequency propagation channels through pipes and ducts for building interior reconnaissanceWhitelonis, Nicholas John, 1984- 12 July 2012 (has links)
Recently, there is strong interest in the through-wall sensing capabilities of radar for use in law enforcement, search and rescue, and urban military operations. Due to the high attenuation of walls, through-wall radar typically operates in the low GHz frequency region, where resolution is limited. It is worthwhile to explore other means of propagating radar waves into and back out of a building’s interior for sensing applications. One possibility is through duct-like structures that are commonly found in a building, such as metal pipes used for plumbing or air conditioning ducts. The objective of this dissertation is to investigate techniques to acquire radar images of targets through a pipe.
First, using the pipe as an electromagnetic propagation channel is studied. A modal approach previously developed for computing the radar cross-section of a circular duct is modified to compute the transmission through a pipe. This modal approach for transmission is validated against measured data. It is also shown that a pipe is a high-pass propagation channel. The modal analysis is then extended to two-way, through-pipe propagation for backscattering analysis. The backscattering from a target is observed through a pipe in simulation and measurement.
Next, methods to form two-dimensional radar images from backscattering data collected through a pipe are explored. Four different methods previously developed for free-space imaging are applied to the problem of imaging through a pipe: beamforming, matched filter processing, MUSIC, and compressed sensing. In all four methods it is necessary to take into account the propagation through the pipe in order to properly generate a focused radar image. Each method is demonstrated using simulation and validated against measurement data. The beamforming and matched filter methods are found to suffer from poor cross-range resolution. To improve resolution, the MUSIC algorithm is applied and shown to give superior resolution at the expense of more complicated data collection. The final method, compressed sensing, is shown to achieve good cross-range resolution with simpler data collection. A comparison of the tradeoffs between the four methods is summarized and discussed.
Two additional extensions are studied. First, a method for computing the transmission through an arbitrary pipe network using the generalized scattering matrix approach is proposed and implemented. Second, a new method for computing joint time-frequency distributions based on compressed sensing is applied to analyze the backscattering phenomenology from a pipe. / text
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