<p> Being the second most important cause of death in women, breast cancer attracted great interest from many research groups in different fields developing techniques to prevent, detect or cure it. Due to the fact that this disease can be treated if it is detected in early stages, many projects in this field have focused on early breast cancer detection. Modern imaging technologies have helped in the detection of this cancer but they still have high false positive or negative rates indicating a great need for more research in early breast cancer detection.</p> <p> In 2002 the Federal Communication Commission allowed usage of 3.1 - 10.6 GHz frequency range for short-range medical and personal applications, and this has stimulated much research on one of the most interesting technologies for medical imaging. With the aid of advances in complementary metal-oxide-semiconductor technology as well as wireless communications, this imaging technology has steadily grow, and now, it has it has many attractive characteristics that makes it a perfect substitute for conventional imaging systems.</p> <p> This thesis reports on the design of some key circuits for an ultra-wideband transceiver architecture that can be used for medical imaging and especially for breast cancer detection. In this work, we concentrated on the receiver and two of its major blocks, namely, a low noise amplifier and a mixer are designed, simulated, fabricated and tested. Both of these circuits are designed in 0 .13 μm technology and Cadence tools are used for simulation and layout. </p> <p> First, a low noise amplifier is designed based on a common-source configuration with inductive degeneration and a third order Chebyshev input matching network. Using precise zero-pole analysis, two inductors have been added to the main architecture of amplifier to improve its gain bandwidth product. The designed circuit shows a very good performance in terms of all of design parameters. Voltage gain with a peak value of 18.6 dB and very acceptable flatness is achieved. Also the noise figure of this circuit had an average of 4.7dB and a minimum value of 3.3dB. Input and output impedance matching shows very satisfying performance for the whole range of 3.1 to 10.6 GHz. Moreover, linearity of the circuit shows a very good performance compared with other works with IIP3 of -0.996 dBm. Finally, all of these specifications are achieved while consuming only 4.01 mW and occupying 1.3 mm2 of chip area.</p> <p> Second, an ultra-wideband mixer is designed to work as a multiplier in this configuration, and to perform a critical function in correlation block. The mixer is designed for both super- and sub-threshold modes of MOSFET operation, and in both modes, it shows very acceptable performance. While super-threshold mixer shows much better characteristics in terms of gain, noise and linearity, the very low power consumption of sub-threshold circuit along with its reasonable performance in terms of gain, noise and linearity makes both circuits excellent designs for niche applications. Excellent conversion gain of 22.54dB is achieved for super-threshold circuit together with minimum noise figure of 7.4 dB and IIP3 of 2.67 dBm, while consuming 6.67 mW and having excellent input impedance matching all over the bandwidth. On the other hand, the sub-threshold circuit dissipates only 623 μW, with 13.44 dB of conversion gain and minimum noise figure of 7.67 and IIP3 of -7.47 dBm. This circuit has excellent input matching all over the UWB frequency range.</p> / Thesis / Master of Applied Science (MASc)

No

The death of one�s parents, irrespective of the age at which it occurs, is generally regarded as a life experience of considerable significance. The last few years of an elderly person�s life are often characterized by increasing frailty, declining health and loss of independence. Responsibility for the spiritual and physical care of parents during that period is undertaken by many adult children. Current research in this area is generally informed by the requirements of social policy, which, by identifying and addressing the inherent difficulties in this so-called informal caring, is designed to support carers in the community. The research reported in this thesis represents a departure from this mode of inquiry and seeks, rather, to explore the existential aspects of caring in this particular situation, from the carer�s perspective. To achieve this objective, an existential phenomenological approach informed principally by the philosophies of Heidegger and Merleau-Ponty, and the adaptation of these philosophies by Schutz, Giorgi and van Manen to social science research, was developed to suit the particular requirements of the topic. In addition to the author�s autobiographic material, primary sources include conversations with five people who had been principal carers for their parents during their final illnesses. In all cases caring had ended with the parent�s death at least one year before the conversations took place. The principal secondary sources are Simone de Beauvoir�s memoir, A Very Easy Death, and Philip Roth�s account of his father�s illness and death, Patrimony: A True Story. In addition, the argument is supported throughout by reference to other literary works. From these sources a number of major existential themes, including temporality, hope, suffering, and knowing the body, have been explored in depth, in conjunction with relevant existential theories. Synthesis of these topics suggests that in this particular circumstance, for the people involved in the study, the phenomenon of caring can be understood as an unconditional engagement with the life and concerns of their parent at the end of life, and can be interpreted within an existential framework as representing an authentic way of Being.

The death of one�s parents, irrespective of the age at which it occurs, is generally regarded as a life experience of considerable significance. The last few years of an elderly person�s life are often characterized by increasing frailty, declining health and loss of independence. Responsibility for the spiritual and physical care of parents during that period is undertaken by many adult children. Current research in this area is generally informed by the requirements of social policy, which, by identifying and addressing the inherent difficulties in this so-called informal caring, is designed to support carers in the community. The research reported in this thesis represents a departure from this mode of inquiry and seeks, rather, to explore the existential aspects of caring in this particular situation, from the carer�s perspective. To achieve this objective, an existential phenomenological approach informed principally by the philosophies of Heidegger and Merleau-Ponty, and the adaptation of these philosophies by Schutz, Giorgi and van Manen to social science research, was developed to suit the particular requirements of the topic. In addition to the author�s autobiographic material, primary sources include conversations with five people who had been principal carers for their parents during their final illnesses. In all cases caring had ended with the parent�s death at least one year before the conversations took place. The principal secondary sources are Simone de Beauvoir�s memoir, A Very Easy Death, and Philip Roth�s account of his father�s illness and death, Patrimony: A True Story. In addition, the argument is supported throughout by reference to other literary works. From these sources a number of major existential themes, including temporality, hope, suffering, and knowing the body, have been explored in depth, in conjunction with relevant existential theories. Synthesis of these topics suggests that in this particular circumstance, for the people involved in the study, the phenomenon of caring can be understood as an unconditional engagement with the life and concerns of their parent at the end of life, and can be interpreted within an existential framework as representing an authentic way of Being.

Breast cancer is a major health problem across the globe. Many incidences in the underdeveloped nations go unreported, due to non-availability or lack of access to breast screening programs. Mammography, the current gold standard for breast screening, comes with several inherent limitations in terms of cost, radiation exposure, and associated discomfort. The cost of equipment and personnel alone puts mammography out of reach for most developing nations. Hence, there is a great and growing need for an adjunct breast screening modality, within reach of general masses, especially in the overpopulated, underdeveloped countries. Digital Image Elasto Tomography (DIET) is intended to be a low cost, radiation free, noninvasive and portable breast cancer screening modality that will be accessible to the general population and will encourage more women to undergo breast screening. The DIET imaging concept induces mechanical vibrations into a breast and its surface motion is captured with digital cameras and reconstructed in 3D, for elastic characterization of the breast tissues. Ex-vivo trials and limited in-vivo trials show promise in breast cancer diagnostic evaluation. The current DIET system is, as noted, functional, but not suitable for wide scale screening. There are significant development issues in hardware, software and algorithms required to improve its speed of testing and quality of diagnostic results. The main aim of this thesis is to overcome these issues taking the DIET system from the lab to a more directly useful and usable system. This thesis presents a complete design development and analysis of the DIET clinical system, developing a prototype suitable for large-scale in-vivo trials, to establish the sensitivity and specificity of this novel technology. The major components of this research are development, of the imaging array to capture surface motion, strobe illumination for reliable image capture, actuation system to vibrate the breast harmonically, remote positioning of the actuator, ergonomic design of the imaging device, and the development of a graphical interface for easy operation of the system. Moreover, anthropomorphic silicone breast phantoms suitable for diagnostic evaluation of elastographic imaging modalities, including DIET and MRE are also presented. A new approach in software based DIET diagnosis through separate modal analysis, focusing on the second natural frequency of the breast, is also presented. Finally, the new DIET technology developed is validated ex-vivo, using two different diagnostic techniques. The trials results are positive and demonstrate viability of this new technology for commercialization. All of these aspects have advanced the clinical and technological future of this overall DIET system concept. The overall thesis makes several technical advances necessary to advance the DIET concept from a purely research concept to clinical feasibility. These advances are coupled within an advanced design to create an all new clinical prototype system. The final, validated result shows the clinical potential, both ex-vivo and in-vivo, and clinical feasibility of the DIET concept and this research.

Pavement rutting is one of the major asphalt pavement surface distresses affecting pavement structure integrity and driving safety and is also a required performance measure specified in the Highway Performance Monitoring System (HPMS). Manual rutting measurement is still conducted by many state Departments of Transportation (DOTs), like Georgia DOT; however, it is time-consuming, labor-intensive, and dangerous. Although point-based rut bar systems have been developed and utilized by state DOTs to measure rutting conditions, they often underestimate rut depth measurements. There is an urgent need to develop an automated method to accurately and reliably measure rutting conditions. With the advance of sensing technology, emerging 3D line laser imaging technology is capable of collecting high-resolution 3D range data at highway speed (e.g., 100 km/h) and, therefore, holds a great potential for accurately and repeatedly measuring pavement rutting condition. The main contribution of this research includes a methodology, along with a series of methods and procedures, for the first time, developed utilizing emerging 3D line laser imaging technology to improve existing 1D rut depth measurement accuracy and repeatability and to measure additional 2D and 3D rutting characteristics. These methods and procedures include: (1) a threshold-based outlier removal method employing the multivariate adaptive regression splines (MARS) technique to remove outliers caused by non-rutting features, such as wide transverse cracks and potholes; (2) a modified topological-ordering-based segment clustering (MTOSC) method to optimally partition the continuous roadway network into segments with uniform rutting condition; (3) an overlapping-reducing heuristic method to solve large-scale segmentation problems; (4) a network-level rutting condition assessment procedure for analyzing 3D range data to statistically interpret the pavement rutting condition in support of network-level pavement management decisions; (5) an isolated rut detection method to determine the termini, maximum depth, and volume of isolated ruts in support of project-level maintenance operations. Comprehensive experimental tests were conducted in the laboratory and the field to validate the accuracy and repeatability of 1D rut depth obtained using the 3D range data. Experimental tests were also conducted in the laboratory to validate the accuracy of 3D rut volume. Case studies were conducted on one interstate highway (I-95), two state routes (SR 275 and SR 67), and one local road (Benton Blvd.) to demonstrate the capability of the developed methods and procedures. The results of experimental tests and case studies show that the proposed methodology is promising for improving the rutting measurement accuracy and reliability. This research is one of the initial effort in studying the applicability of this emerging sensing technology in pavement management. And the outcomes of this research will play a key role in advancing state DOTs’ existing pavement rutting condition assessment practices.

Submitted by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2016-04-14T17:34:26Z No. of bitstreams: 1 Dissertação. Mariana Ramos Pitta Lima. 2015.pdf: 1479737 bytes, checksum: 7c0a70d47fe34eb6897746d012ce177f (MD5) / Approved for entry into archive by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2016-04-18T12:42:34Z (GMT) No. of bitstreams: 1 Dissertação. Mariana Ramos Pitta Lima. 2015.pdf: 1479737 bytes, checksum: 7c0a70d47fe34eb6897746d012ce177f (MD5) / Made available in DSpace on 2016-04-18T12:42:34Z (GMT). No. of bitstreams: 1 Dissertação. Mariana Ramos Pitta Lima. 2015.pdf: 1479737 bytes, checksum: 7c0a70d47fe34eb6897746d012ce177f (MD5) / Este artigo analisa as práticas e os significados em torno da ultrassonografia obstétrica (USG) realizada em mulheres com abortamento em ―MPS‖, uma maternidade pública em Salvador, Bahia, Brasil. Especificamente, explora as noções de Pessoa acionadas pelos sujeitos nas relações com a produção de imagens durante exame de USG, com base na análise de registros de observação participante, durante três meses, na sala em que o exame é realizado. A partir desse enfoque, buscamos identificar as noções de ‗gravidez‘, ‗concepto‘ e ‗feto-pessoa‘ constituídas pelos ecografistas e pelas mulheres com abortamento nas interações observadas. O artigo mostra como a USG ocupa um lugar central no itinerário abortivo das mulheres. Sua realização é uma prática incorporada e definidora de condutas na atenção ao abortamento nesse hospital público da rede SUS. Para os profissionais, todas as usuárias do serviço de USG estudado que chegam com sangramento são suspeitas a priori de terem provocadas um aborto – até provado o contrário. A etnografia revelou que nesse contexto se constitui três categorias distintas de ‗mulheres com aborto‘, cujo acionamento depende da interpretação da imagem ecográfica da condição e do conteúdo do útero. São mulheres com aborto completo, sem qualquer resto embrionário; mulheres com abortamento incompleto com alguns restos; e mulheres com ameaça de aborto com fetos ainda vivos. A forma de significar o estado de saúde e a condição moral de uma mulher com suspeita de aborto se relaciona com a presença ou não de um feto vivo no seu útero, além da idade gestacional em que a suspeita de abortamento ou o aborto aconteceu. Concluímos que, do ponto de vista simbólico, mulheres e profissionais colaboram ao produzir, a partir da interpretação da imagem ecográfica, um conhecimento sobre a gravidez, entendida como um processo que envolve estágios distintos. Quando as evidencias ecográficas indicam que houve (provavelmente) um aborto nos estágios iniciais de uma gravidez, os próprios profissionais colaboram com as mulheres em desativar o processo semiótico que levaria à atribuição de um sentido de natureza humana ao concepto. Por outro lado, quanto mais tarde se interrompeu uma gestação, mais provável é que o processo de significação sobre as imagens sustente a ideia de que ali havia Pessoa. Nesse caso e, sobretudo quando se detectou presença de um feto com vida, mais enfática se torna a condenação moral do ato do abortamento. A moral hegemônica sobre aborto e sua criminalização modulam as construções simbólicas e as práticas em torno do exame de USG em mulheres com abortamento.

No / X-radiography of textile objects reveals hidden features as well as unexpected components and materials. This non-destructive technique throws light on construction, manufacturing techniques, use, wear, repair, patterns of decay and dating. X-radiography improves artefact documentation and interpretation as well as guiding conservation approaches by enhancing understanding. This book explores techniques for X-raying textiles. It describes approaches to image interpretation and explains how, through digitisation and digital image manipulation, maximum information can be realised. Case studies include archaeological, ecclesiastical and ethnographic textiles, items of dress and accessories, upholstery, quilts, embroideries, dolls and toys. Museum professionals will find this stimulating book an essential guide for developing their own practice or commissioning textile X-radiographs.

Although current head imaging technologies such as magnetic resonance imaging (MRI) and computed tomography (CT) are capable of providing accurate diagnosis of brain injuries such as stroke and brain tumour, they have several limitations including high cost, long scanning time, bulky and mostly stationary. On the other hand, radar-based microwave imaging technology can offer a low cost, non-invasive and non-ionisation method to complement these existing imaging techniques. Moreover, a compact and wearable device for microwave head imaging is required to facilitate frequent or real-time monitoring of a patient by providing more comfort to the patient. Therefore, a wearable head imaging device would be a significant advantage compared to the existing wideband microwave head sensing devices which typically utilise rigid antenna structure. Furthermore, the wearable device can be integrated into different microwave imaging setups such as real-time wearable head imaging systems, portable systems and conventional stationary imaging tools for use in hospitals and clinics. This thesis presents the design and development of wearable devices utilising flexible antenna arrays and compact radio frequency (RF) switching circuits for wideband microwave head imaging applications. The design and characterisation of sensing antennas using flexible materials for the wearable head imaging device are presented in the first stage of this study. There are two main variations of monopole antennas that have been developed in this research, namely trapezoidal and elliptical configurations. The antennas have been fabricated using different flexible substrate materials such as flexible FR-4, polyethylene terephthalate (PET) and textile. Wideband performances of the antennas have been achieved by optimising their co-planar waveguide feeding line structures. Importantly, the efficiencies of the fabricated antennas have been tested using a realistic human head phantom by evaluating their impedance matching performances when operating in close proximity to the head phantom. The second stage of the study presents the development of wearable antenna arrays using the proposed flexible antennas. The first prototype has been built using an array of 12 flexible antennas and a conformal absorbing material backed with a conductive sheet to suppress the back lobe radiation of the monopole antennas. Additionally, the absorber also acts as a mounting base to hold the antennas where the wearable device can be comfortably worn like a hat during the measurement and monitoring processes. The effect of mutual coupling between adjacent antennas in the array has been investigated and optimised. However, the use of the absorbing material makes the device slightly rigid where it can only be fitted on a specific head size. Thus, a second prototype has been developed by using a head band to realise a stretchable configuration that can be mounted on different sizes of human heads. Furthermore, due to the stretchable characteristic of the prototype, the antennas can be firmly held in their positions when measurements are made. In addition, fully textile based sensing antennas are employed in this prototype making it perfectly suitable for monitoring purposes. Low cost and compact switching circuits to provide switching mechanism for the wearable antenna array are presented in the third stage of this study. The switching circuit is integrated with the antenna array to form a novel wearable microwave head imaging device eliminating the use of external bulky switching network. The switching circuit has been built using off-the-shelf components where it can be controlled wirelessly over Bluetooth connection. Then, a new integrated switching circuit prototype has been fabricated using 6-layer printed circuit board (PCB) technology. For the purpose of impedance matching for the radio-frequency (RF) routing lines on the circuit, a wideband Microstrip-to-Microstrip transition is utilised. The final stage of this study investigates the efficacy and sensitivity of the proposed wearable devices by performing experiments on developed realistic human head phantoms. Initially, a human head phantom has been fabricated using food-based ingredients such as tap water, sugar, salt, and agar. Subsequently, lamb's brains have been used to improve the head phantom employed in the experiments to better mimic the heterogeneous human brain. In terms of imaging process, an interpolation technique developed using experimental data has been proposed to assist the localisation of a haemorrhage stroke location using the confocal delay-and-sum algorithm. This new technique is able to provide sensible accuracy of the location of the blood clot inside the brain. The wearable antenna arrays using flexible antennas and their integrations with compact and low cost switching circuits reported in this thesis make valuable contribution to microwave head imaging field. It is expected that a low-cost, compact and wearable radar-based microwave head imaging can be fully realised in the future for wide range of applications including static scanning setup in hospitals, portable equipment in ambulances and as a standalone wearable head monitoring system for remote and real-time monitoring purposes.

O foco central desta tese consiste em procurar compreender um fenômeno que se verifica na atualidade em torno das imagens ultra-sonográficas fetais. O que era a princípio e em princípio uma tecnologia de imagem médica, inventada com propósitos diagnósticos, gradualmente transformou-se em objeto de consumo e lazer. Para investigar o fenômeno, a pesquisa teórica aborda como foram construídos o olhar e o observador modernos, e de que modo as tecnologias de imageamento médico incidem na construção social do corpo. Outro aspecto teórico consiste na investigação, de um ponto de vista sócio-histórico, acerca da produção da gravidez e do feto como temas médicos, e de que modo a tecnologia de ultra-som aplicada à obstetrícia está situada na articulação de vários processos: o da construção de um novo olhar, o das reconfigurações do corpo, o da medicalização da gestação e do feto e, finalmente, o da construção do feto como Pessoa antes de seu nascimento. Estudos antropológicos produzidos no exterior, ao longo da década de 1990, apontaram que o fenômeno envolvendo as imagens fetais encontrava-se inscrito nos e delimitado pelos códigos socioculturais específicos de onde ocorriam. A inexistência de pesquisas acerca do tema, no contexto brasileiro, foi o ponto de partida para uma investigação empírica. Foi realizada uma observação antropológica de ultra-sonografias obstétricas, em abordagem etnográfica, em três clínicas privadas de imagem, ao longo de 2003, no Rio de Janeiro, visando compreender como tal fenômeno se dava, de que modo era produzido e significado pelos atores e quais os desdobramentos de tais práticas, modelados por especificidades culturais locais. O trabalho de campo evidenciou que a ultra-sonografia obstétrica caracteriza-se por ser uma tecnologia de imagem interativa, em contraste com outras técnicas de imageamento médico, uma peculiaridade que propicia a construção de diversos significados a partir das imagens fetais cinzentas e esfumaçadas. A produção do prazer de ver o feto é a pedra de toque que une o útil ao agradável, e o consumo de imagens é um ponto de articulação de diversas questões expostas ao longo da tese. Pode-se pensar nesta situação como parte de um panopticismo que devassa corpos femininos e fetais, em um mesmo processo normatizando-os e construindo novos sujeitos calcados em corporalidades virtuais. / The central focus of this thesis consists of seeking to understand a phenomenon which is presently taking place in the area of fetal ultrasound images. What began as a medical imaging technology, invented for diagnostic purposes, gradually became an object of consumption and leisure. In order to investigate this phenomenon, the theoretical investigation looks at how the modern mode of seeing and the observer were constructed, and in what way technologies of medical imaging impact the social construction of the body. Another theoretical aspect consists of the investigation, from a socio-historical point of view, of the production of pregnancy and of the fetus as medical subjects, and in what way the technology of ultra-sound applied to obstetrics is situated at the nexus of various processes: the process of constructing a new mode of seeing, of the reconfigurations of the body, of the medicalization of gestation and of the fetus, and, finally, of the construction of the fetus as a person before its birth. Anthropological studies carried out abroad, during the nineties, show that the phenomenon involving fetal images was inscribed in and delimited by the specific socio-cultural codes where the imaging was done. The lack of research in this area in the Brazilian context was the point of departure for an empirical investigation. An anthropological observation of obstetric ultra-sounds, with an ethnographic approach, was carried out in three private imaging clinics, during the course of 2003, in Rio de Janeiro, with the intention of understanding how this phenomenon took place, in what way it was produced and signified by those involved, and what were the ramifications of these practices, modeled by local cultural particularities. The field work showed that obstetric ultrasonography can be characterized as an interactive imaging technique, in contrast to other medical imaging techniques, a peculiarity which lends itself to the construction of various significations having as their origin gray and hazy fetal images. The production of the pleasure of seeing the fetus is the touchstone which links the useful to the pleasing, and the consumption of images is point of connection for various questions raised in the thesis. One can think of this situation as part of a panopticism which scans female and fetal bodies, at one and the same time normatizing them and constructing new subjects shaped by virtual corporalities.