No description available.

Made available in DSpace on 2014-06-12T15:56:57Z (GMT). No. of bitstreams: 2 arquivo3096_1.pdf: 4031500 bytes, checksum: 3cfbafa985058f2171a93b3e230c2c35 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009 / Desde equipamentos de vigillância por vídeo a câmeras digitais e telefones celulares, a detecção de rostos e uma funcionalidade que esta rapidamente ganhando peso no projeto de interfaces de usuario mais inteligentes e tornando a interação homem-maquina cada vez mais natural e intuitiva. Com isto em mente, fabricantes de chips estão embarcando esta tecnologia na sua nova geração de processadores de sinal de imagem (ISP) desenvolvidos especificamente para uso em aparelhos celulares. O foco deste trabalho foi analisar um algoritmo para detecção de rostos para suportar a definição da arquitetura mais adequada a ser usada na solução final. Um algoritmo inicial baseado na tecnica de Cascata de Caracteristicas Simples foi usado como base para este trabalho. O algoritmo inicial, como especificado, leva quase quarenta segundos para processar um unico quadro de imagem no processador alvo, tempo este que inviabilizaria o uso desta solução. Focando na implementação de um novo ISP, o algoritmo foi completamente reescrito, otimizado e propriamente mapeado na plataforma alvo, ao ponto onde um fator de aceleração de 167x foi atingido e uma imagem de pior caso agora leva menos de 250 milissegundos para ser processada. Este numero e ainda mais baixo se for considerada a media em um conjunto maior de imagens ou um vídeo, caindo para cerca de 100 milissegundos por quadro de imagem processado. Não obstante, performance não foi o unico alvo, tambem a quantidade de memoria necessaria foi dramaticamente reduzida. Isto tem um impacto direto na area de silicio requerida pelo circuito e conseq uentemente menores custos de producao e consumo de potência, fatores criticos em um sistema para aplicações moveis. E importante ressaltar que a qualidade não foi deixada de lado e em todas as otimizações realizadas, tomou-se o cuidado de verificar que a qualidade de detecção não tinha sido impactada. Este documento apresenta a pesquisa feita e os resultados obtidos. Começa por uma breve introdução ao assunto de Visão Computacional e aos desafios de projetar uma solução de detecção de rostos. Apos esta introdução, o algoritmo que serviu como base para este trabalho e apresentado juntamente com as otimizações mais relevantes ao nivel algoritmico para melhorar a performance. Na sequência, instruções customizadas desenvolvidas para acelerar a execução do algoritmo na solução final são apresentadas e discutidas

The phenomenon of rapid increment of the mobile phones can be utilized through supporting patients, such as those who have tuberculosis, for treatment adherence. This utilization will enable these patients to directly communicate their needs and requirements or receive health information such as reminder messages from healthcare facilities. However, the current mobile interventions, such as text messaging and speech reminder systems have limited use for people with low literacy levels. To overcome these challenges, this study proposed that the mobile graphic-based reminders be used to support tuberculosis patients to improve compliance with treatment regimens, especially for semi-literate and illiterate patients. A review of the literature and initial investigation study were carried out. The findings from the review were useful in understanding both the current practice of tuberculosis treatment regimens and the patients' needs and requirements. These findings, in addition, were referred in the choices of the components of the mobile graphic-based reminders to be implemented. A visual aid for communication theory was applied to the design and development of graphic-based reminder prototypes. An application prototype was implemented for the Android platform. Experiments were conducted to investigate the effects of an application prototype in supporting tuberculosis treatment. To measure the effect, the recovery rate was measured based on the effect of: (1) the graphic-based reminder group versus the control group; and (2) the graphic-based reminder group versus the speech-based reminder group. Data was collected using application event logs, interviews, field notes and audio recordings. It was found that treatment adherence of patients in the graphic-based group was higher than in the speech-based or in the control groups. It was further noted that the number of reminder responses in the graphic-based group was higher than in the speech-based group. Additionally, it was observed that patients in the graphic-based group responded sooner after receiving reminder messages compared to those in the speech-based group. The qualitative feedback also indicated that most patients not only found graphic-based reminders more useful to supporting their treatment than speech-based reminders and traditional care but believed that the application met their needs. This study provides empirical evidence that graphic-based reminders, designed for and based on patients' needs and requirements, can support the treatment of tuberculosis for patients of all literacy levels.

Surveillance cameras are integral in assisting law enforcement by collecting video information that may help officers detect people for whom they are looking. While surveillance cameras record the area covered by the camera, unlike humans, they cannot "understand" what is happening. My research uses multiple curvilinear regression models to accurately place differentially corrected GPS points with submeter accuracy onto a camera image. Optimal results were achieved after splitting the image into four zones with the focus on calibrating each area separately. This resulted in adjusted R2 values as high as 99.8 percent, indicating that high quality GPS points can form a good manual camera calibration. To ascertain whether or not a lesser quality GPS point associated with a social media application would allow location of the person sending the message, I used an iPhone 5s to do a follow up. Using the zone-based calibration equations on GPS point locations from an iPhone 5s show that the locations collected are less accurate than differentially corrected GPS locations, but there is still a decent chance of being able to locate the correct person in an image based off that person's location. That chance, however, depends on the population density inside the image. Pedestrian density tests show that about 70-80 percent of the phone locations in a low-density environment could be used to locate the correct person that sent a message while 30-60 percent of the phone locations could be used in that manner in a high-density environment. / Master of Science

Throughout the developing world, the mobile phone has been heralded as a tool that can empower and lift women out of vulnerable situations. While many scholars and development professionals believe that phones empower women, some contend that phones amplify disparities for people who are not well-positioned in society. To better understand how the diffusion of phones has impacted women, this thesis examines the relationship between mobile phones and socially constructed gender-based inequalities in agro-pastoralist Maasai communities in northern Tanzania. Grounded in perspectives from scholarship on women's empowerment and rural liveihoods, I ask: (1) how do women access and use phones?; and (2) how are women's phone uses embedded in existing social relations? This research relies on semi-structured interviews and household surveys conducted in the summer of 2018 to identify Maasai women's perspectives on phones, social relations, and power. Through inductive and deductive qualitative content analysis, findings indicate that phone access is fluid. There are a multitude of relationships between phones and empowerment, and these relationships are not only a function of a woman's personal choice and characteristics, but often more importantly her position in the household, the household norms her husband controls, and her husband's attributes. These results help show how women's empowerment in patriarchal societies, which may be afforded by new technologies, is guarded by men and subject to their discretions. This study highlights the importance of engaging men and women in discussions of and interventions surrounding women's empowerment. / Master of Science / Mobile phones are used throughout the world, even in rural, developing areas. Both men and women are adopting cell phones that can provide access to greater amounts and different types of information that was previously inaccessible. Some development professionals and scholars argue that mobile phones are a tool that can empower marginalized communities, like women. Others contend that mobile phones fail to transform the lives of women due to existing gender inequalities. My research seeks to answer the question: do mobile phones empower women by increasing access to resources and enhancing decision-making power? This research is situated in northern Tanzania in predominately ethnically Maasai communities where patriarchal (system controlled by men) and polygynous (marriage of one man with several women) practices essentially give men the power to determine the responsibilities, roles, and rights of all community members. These practices are embedded in important traditions that help Maasai communities cope with stress and maintain or enhance life now and for future generations. The widespread adoption of mobile phones creates an opportunity for novelty in these traditional norms. To understand how Maasai women may use mobile phones to challenge traditional practices that permit gender inequalities, this study conducted interviews and surveys with women in ten rural communities to examine: if and how women access and use mobile phones; the opportunities and challenges that mobile phones present; how women leverage phones to access resources and practice agency (having options and the ability to define and act on goals); and how social position in the household interacts with processes of empowerment that phones may permit. Findings show that there is no single relationship between mobile phones and empowerment, but rather a multitude of relationships that are influenced by social position both in and out of the household. This study illustrates the importance of considering local socio-cultural norms and engaging men in development interventions for women’s empowerment.

<p>In recent years mobile phones have become very popular in India, even among the poorer parts of the population. Our aim was to study how this has affected the small businesses. During the fall of 2007 we made 44 interviews with various businessmen in two states in northern India, Rajasthan and Orissa. During the study we found that the access to mobile phones had had altered the way business is handeled on many levels. The businessmen had gotten more customers, more time on their hands and they had changed they way they handeled supplies and suppliers. The ultimate effect of this was an increase in personal income.</p>

The older population is increasing, as is life expectancy. Technical devices are becoming more widespread and used for many everyday tasks. Knowledge about new technology is important to remain as an active and independent part of the society. However, if an old user group should have equal access to this technology, new demands will be placed on the design of interfaces and devices. With respect to old users it is and will be important to develop technical devices and interfaces that take the age-related decline in physical and cognitive abilities into account. The aim of this work was to investigate to what extent the age-related cognitive decline affects performance on different computer-related tasks and the use of different interfaces. With respect to the use of computer interfaces, two studies were conducted. In the first study, the information was presented with a hierarchical structure. In the second study the information was presented as a 3D-environment, and it was also investigated how an overview map could support navigation. The third study examined the age-related cognitive decline in the use of a small mobile phone display with a hierarchical information structure. The results from the studies showed that the most pronounced age-related difference was found in the use of the 3D-environment. Within this environment, prior experience was found to have the largest impact on performance. Regarding the hierarchical information structures, prior experience seemed to have a larger impact on performance of easy tasks, while age and cognitive abilities had a larger impact on performance of more complex tasks. With respect to navigation aids, the overview map in the 3D-environment did not reduce the age-differences; however, it contributed to a better perceived orientation and reduced the feeling of being lost.

Thesis advisor: Timothy Duket / What is the relationship between inequality and the prevalence of mobile phones in a society? It is obvious that being poor is a barrier to owning a mobile phone, but what about simply being poorer than those around you? Stories abound about the benefits mobile phones bring to the poor in developing countries. For example, in Bangladesh's Narshingdi district, mobile phones have made it possible for families who once struggled to survive, to earn more than enough to eat well and live comfortably. These isolated villagers who grow crops or raise livestock can use their village cell phone to speak directly to wholesalers and are able to get better prices for their goods in the marketplace (Ahmed, 2000). In Cote d'Ivoire coffee growers share mobile phones to follow hourly changes in coffee prices in order to sell at the most profitable time (Lopez, 2000). But how likely will these poor people be to access a mobile phone if they are significantly poorer than the “rich” in their countries. In place where there is such a disparity, does unequal income distribution make it less likely that someone will own a cell phone, or does something about the condition make adopting this technology even more widespread? As it turns out, the results of this study indicate that the higher the level of inequality in a country, the more likely someone living there is to own a cell phone. While this result seems counterintuitive, I will discuss in detail a few ways to explain it after giving some background on the subject. / Thesis (BA) — Boston College, 2003. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Economics. / Discipline: College Honors Program.

The effects of mobile phone-like electromagnetic radiation on the human brain activity are examined. The research focuses on both radio frequency (RF) exposures and the much less studied low frequency (ELF) exposures (less than 40 kHz) arising from the battery operation of GSM handsets. The first single blind study recruited a small sample of twelve human volunteers. The eyes closed resting EEG activity is monitored after radio frequency exposure. With SAR levels of 2 W/kg, results reveal no statistical changes in any of the examined frequency bands for neither pulsed modulated RF signals nor continuous wave RF signals. In the second double blind study, a sample of 72 volunteers is recruited and an improved protocol comprised of separate pulsed RF, continuous RF and pulsed ELF exposures is employed. Exposures are delivered through a custom made handset capable of independent RF and ELF exposures. Findings include a reduced alpha band frequency activity during pulsed radio frequency and low frequency radiations exposures but no changes under the continuous RF radiation. Changes are present both during as well as after exposure, while greater changes are observed during exposures. The study of some non linear measures of the resting EEG revealed no changes under any of the active exposures. As the observed changes are very close to the normal EEG variation during resting conditions, their biological significance and health impact is not immediately obvious. However, their mere demonstration points to a low level interaction mechanism which may deserve further study.

This thesis aims to determine whether RF pulsed exposures from mobile phones can influence nervous function within the human brain and heart. In order to address this objective, a robust double-blind study to investigate mobile phone exposures on nervous response has been undertaken by means of analysis of electrophysiological test measures of brain wave activity and heart responses. Generally, test measurements of the electroencephalogram (EEG), the electrocardiogram (ECG), and the pulse plethysmogram (PPG) (for indications of blood pressure response) have been undertaken whilst participants are exposed and sham exposed to various GSM mobile phone radiofrequency and low-frequency protocols. In initial work, both standby and full-power mode GSM exposures have been investigated (Chapter 3 - EEG investigated only), while pulsed 900 MHz and 1800 MHz continuous wave exposures have been investigated in the final experimental work involving 100 test participants (Ch apter 8 - EEG, ECG, and PPG measures are investigated). Four predominant outcomes are determined from the final experimental work conducted. These main outcomes specifically include: 1. A new 'characteristic' finding in the EEG alpha band (8-13 Hz) as due to 900 MHz exposures is observed from almost all recording sites, over both brain hemispheres. Notably, this response only appears at 900 MHz, though is not observable for the 1800 MHz exposure; 2. An EEG effect due to both pulsed 900 MHz and 1800 MHz exposures notably appearing at 16 Hz is a new critical finding and is observed across both hemispheres. Most importantly, at this beta rhythm only a decreasing tendency in EEG power can be noted for the 900 MHz exposure tested but only an increasing tendency in EEG power may be noted at 1800 MHz, suggesting that the direction of the effect in EEG power may be dependent on the RF component; 3. Effects at 900 MHz on the contralateral side to exposure at central, temporal, and parietal sites appear to indicate a common median difference response between sham and exposure EEG spectral power density, which does not appear on the ipsilateral side to exposure; 4. As consistent with most previously published research, 900 MHz or 1800 MHz exposures pulsed at 217 Hz do not appear to alter heart rate, heart rate variability (HRV), or blood pressure variability (BPV). To reduce confounding factors and errors in experimental results, several novel approaches were developed as described (Chapters 4 - 8). These approaches include the development and testing of an experimental handset to support multiple mobile phone signals, a comparative analysis of 900 MHz and 1800 MHz exposures (near the health protection limits) on the same group of participants in simultaneous experiments, development of a statistical analysis approach to EEG that addresses both type 1 and type 11 errors at high resolution, and quantification of potential effects of EEG recording leads on SAR and electric field distribution (at both 900 MHz and 1800 MHz) inside a SAM phantom and realistic computational head model. Outcomes of this research address forefront international health concerns regarding almost 2-billion mobile phone users worldwide.