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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
401

Governo eletrônico e inovação de processo : estudo de caso do portal do Estado do Rio Grande do Sul

Kiekow, Andrea Simoni 31 August 2017 (has links)
A administração pública, em suas esferas de atuação, utiliza-se de mecanismos para intensificar e facilitar relações entre cidadãos e governos, por intermédio de inovações de processo. Com a utilização da internet, percebe-se a modernização e aproximação dos segmentos da sociedade com o governo, permitindo ofertar serviços públicos de forma eficiente e efetiva. Em vista disso, o presente estudo teve por objetivo identificar a percepção dos gestores públicos municipais na utilização do portal eletrônico do Estado do Rio Grande do Sul quanto à inovação de processo. Para tanto, foi realizada pesquisa aplicada, quantitativa, descritiva por meio de survey, com 62 gestores municipais dos 497 municípios do Rio Grande do Sul. Como resultados observou-se que o portal eletrônico possibilita melhorias nos serviços públicos e agilidade, auxilia na elaboração de políticas públicas, melhora a interação da sociedade com o governo e a transparência dos atos públicos. Além disso, o portal eletrônico é visto como inovação de processos, que minimiza gastos da administração pública e dos usuários, e possibilita melhorias nos processos para o cidadão. Identificou-se ainda por meio de análise fatorial, que os fatores agruparam-se em três fatores, sendo eles tecnologia, processos, e interação, não apresentando diferenças entre os resultados dos grupos por mesorregiões do Rio Grande do Sul. Por fim, observou-se ainda que há correlação significativa entre Tecnologia e Processos (0,680), Tecnologia e a Interação (0,740), e Processos e a Interação (0,616), indicando que quanto melhores os resultados de um dos fatores na gestão pública, melhores serão os resultados dos demais fatores. / The public administration, in its spheres of action, uses mechanisms to intensify and facilitate relations between citizens and governments, through process innovations. With the use of the Internet, the modernization and approximation of the segments of society with the government is perceived, allowing to offer public services in an efficient and effective way. In view of this, the present study aimed to identify the perception of municipal public managers in the use of the electronic portal of the State of Rio Grande do Sul regarding process innovation. For that, a quantitative descriptive survey was carried out with 62 municipal managers from the 497 municipalities of Rio Grande do Sul. As a result, it was observed that the electronic portal allows improvements in public services and agility, helps in the elaboration of Enhances society's interaction with government and the transparency of public acts. In addition, the e-portal is seen as process innovation, which minimizes public administration and user spending, and enables process improvements for the citizen. It was also identified by means of factorial analysis, that the factors were grouped in three factors, being technology, processes, and interaction, not presenting differences between the results of the groups by mesoregions of Rio Grande do Sul. Finally, it was observed although there is a significant correlation between Technology and Processes (0.680), Technology and Interaction (0.740), and Processes and Interaction (0.616), indicating that the better the results of one of the factors in public management, the better the results of the other factors.
402

Design multi-dispositivo em contextos de uso alternado e migração de tarefas / Multi-device design in contexts of interchange and task migration

Oliveira, Rodrigo de 30 May 2008 (has links)
Orientador: Heloisa Vieira da Rocha / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-11T08:22:19Z (GMT). No. of bitstreams: 1 Oliveira_Rodrigode_D.pdf: 16111521 bytes, checksum: 6c77c064d781230212b6c88feb0bcb6c (MD5) Previous issue date: 2008 / Resumo: Com a miniaturização dos componentes digitais e o vasto desenvolvimento tecnológico dos últimos anos, a sociedade tem presenciado a redefinição dos "computadores pessoais" pelo advento dos dispositivos móveis. Além da inovação, eles introduziram o desafio do design multi-dispositivo para as aplicações desktop. Enquanto algumas abordagens criaram interfaces móveis sem aproveitar qualquer modelo, outras buscaram adaptações automáticas visando reduzir a sobrecarga de designo Em ambas, o foco do design deixou de ser o usuário, tornando as interfaces tão diferentes ao ponto de comprometerem a usabilidade na realização de uma mesma tarefa em vários dispositivos. Esta tese afirma que não existe uma abordagem de design multi-dispositivo capaz de garantir boa usabilidade em todos os contextos porque o usuário pode escolher apenas uma forma de acesso à aplicação ou alternar seu uso por meio de vários dispositivos. No primeiro caso, o usuário aprende a usar a interface para realizar suas tarefas, sendo relevante uma abordagem que aproveite os recursos do dispositivo e trate suas limitações. No segundo, o usuário já conhece uma das interfaces, o que gera uma expectativa no uso das demais. Logo, é necessário combinar abordagens com objetivos diferentes para atender ao usuário de acordo com o seu contexto de uso. Neste sentido, propõe-se o design multi-dispositivo por meio da preservação de uma hierarquia de prioridades de consistência definida em três níveis. Enquanto os dois primeiros dão suporte à expectativa do usuário em contextos de uso alternado (propensos à execução de tarefas em dispositivos diferentes) e migração de tarefas (iniciando tarefas com um dispositivo e concluindo com outro), o terceiro nível garante a personalização das tarefas de maior interesse visando eficiência e satisfação de uso em um dispositivo específico. A avaliação desta metodologia foi feita por meio de um experimento com três interfaces de pocket PC construídas a partir de uma aplicação desktop do domínio de Educação a Distância: a primeira delas era uma réplica da original (Migração Direta), a segunda não mantinha consistência de layout e era baseada em um processo de design personalizado adequado ao dispositivo (Linear) e a terceira aplicava apenas os dois primeiros níveis da hierarquia de prioridades (Overview). Os resultados da avaliação subjetiva mostraram que a abordagem Overview foi capaz de manter o modelo mental do usuário com maior precisão por preservar os atributos de facilidade, eficiência e segurança de uso na interação inter-dispositivo. Além disso, os resultados medidos para a eficácia (exatidão das respostas) e eficiênciá (tempo médio de execução das tarefas) foram iguais ou melhores com essa abordagem. Por outro lado, os usuários revelaram uma preferência pela personalização de tarefas presente na abordagem Linear. Este resultado dá suporte à proposta desta tese, mostrando que a eficácia gerada pelos dois primeiros níveis da hierarquia de prioridades (percepção e execução das tarefas) deve ser combinada com o terceiro nível de personalização. Para isso, sugere-se a disponibilização de padrões de interface criados pelo designer para escolha do usuário durante a interação. Essa combinação deve garantir usabilidade no acesso a uma aplicação feito sempre por um mesmo dispositivo ou em contextos de uso alternado e migração de tarefas / Abstract: With the miniaturization of digital components and the vast technological development of the past years, society has remarked the redefinition of "personal computers" by the advent of modern mobile devices. Besides the innovation, these handhelds also introduced the challenge to develop multi-device interfaces for today's desktop applications. While some created mobile interfaces from scratch to get the best from the devices, others looked for automatic adaptations to reduce the load imposed to the designeI. In both cases, the user wasn't the focus anymore, which resulted interfaces so different from each other to the point of compromising usability when peHorming one task on many devices. This thesis claims that there is no multi-device approach capable to provi de full usability in every context because the user may choose only one interface to access the application or interchange its use via many devices. In the first case, the user learns to perform tasks with the given device, which makes relevant an approach that takes advantage of its resources and solves its limitations. In the second, the user already knows one of the available interfaces, which generates an expectation for the others. Therefore, it is necessary to combine approaches with different goals and suit the user according to the appropriate context. In this sense, we propose multi-device design via maintenance of a consistency priorities hierarchy defined in three levels. The first two levels give support to the user's expectation in contexts of interchange (prone to task execution with different devices) and task migration (starting tasks with one device and finishing with other). On the other side, the third level provides task personalization according to the user's interest towards higher efficiency and satisfaction of use with a specific device. The evaluation of this methodology was conducted by an experiment with three pocket PC interfaces designed from an e-learning desktop application: the first interface was an exact replica of the original desktop version (Direct Migration), the second didn't maintain layout consistency and was based in a personalized design process adequate to the device (Linear) while the third applied only the first two levels of the consistency priorities hierarchy (Overview). The subjective evaluation results pointed the Overview approach as the best to maintain the user's mental model by preserving easiness, efficiency and safety of use on inter-device interaction. Additionally, both measured efficacy (task result accuracy) and efficiency (task execution mean time) were the same or even better with this approach. On the other hand, users revealed their preference for the task personalization present in the Linear approach. This result gives support to our proposal, corroborating that the efficacy generated by the first two levels of the consistency priorities hierarchy (task perception and execution) should be combined with the third level of personalization. This could be done by letting designers create interface patterns and make them available to users during interaction. Such combination should guarantee usability while constantly accessing one application through the same device or in contexts of alternated use and task migration / Doutorado / Doutor em Ciência da Computação
403

Um framework para adaptação de conteúdo e navegação em portais de governo eletrônico / A framework for content and navigation adaptation in electronic government portals

Viana, Giovanni Bogéa, 1981- 21 August 2018 (has links)
Orientador: Maria Beatriz Felgar de Toledo / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-21T17:36:38Z (GMT). No. of bitstreams: 1 Viana_GiovanniBogea_D.pdf: 4687841 bytes, checksum: d213ca93eb3113229d6c6c30545c9515 (MD5) Previous issue date: 2012 / Resumo: Um dos objetivos do governo eletrônico é possibilitar acesso a dados oficiais a todos os públicos. No entanto, não basta que os dados estejam formalmente disponíveis, é preciso que sejam compreensíveis. Essa compreensão, por sua vez, não é homogênea entre os diversos públicos. Cada indivíduo possui limitações e características próprias, que levam a diferentes expectativas de como as informações devem ser disponibilizadas. Esta Tese apresenta um framework para tratar as diferentes classificações que os dados podem ter dependendo de quem está consultando a informação. Teve como motivação uma pesquisa realizada com usuários de um importante sítio de governo eletrônico no Brasil, o Portal da Transparência. Seu aspecto inovador é permitir que as diferentes classificações sejam apresentadas de acordo com o público, possibilitando uma maior inclusão digital / Abstract: One of the e-government goals is to enable public access of official information to all citizens. However, it is not enough to formally present the data, but they have to be truly understandable. This understanding, in turn, is not homogeneous for various audiences. Each individual has his own characteristics and limitations, which leads to different expectations on how information should be available. This Thesis presents a framework to address the different classifications of data that may exist depending on who is getting the information. It was based on a survey with users of an important e-government site in Brazil, the Transparency Portal1. Its novel aspect is allowing data presentation in different ways according to the classifications expected by groups of individuals to achieve a better digital inclusion / Doutorado / Ciência da Computação / Doutor em Ciência da Computação
404

Um método para avaliação remota e automatizada de usabilidade de aplicações Web / A method for remote and automatic usability evaluation of Web applications

Vargas, Ariel, 1981- 05 October 2012 (has links)
Orientador: Heloísa Vieira da Rocha / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-20T14:48:06Z (GMT). No. of bitstreams: 1 Vargas_Ariel_D.pdf: 20092407 bytes, checksum: a759e10b287a819834ba069524f29fee (MD5) Previous issue date: 2012 / Resumo: Observar as ações de usuários interagindo com a interface de uma aplicação computacional é a base de métodos tradicionais de avaliação de usabilidade, como os testes com usuários e a observação em campo. Apesar de populares e eficientes na descoberta de problemas, esses métodos tradicionais são considerados bastante caros, devido aos custos de envolver usuários, de preparar a infra-estrutura e especialmente da própria execução dos métodos e análise de seus resultados. A qualidade dos resultados da execução desses métodos depende da escolha dos usuários participantes da avaliação, que precisam ser representativos de todos os perfis de usuários da aplicação avaliada. Na Web, devido à diversidade e característica distribuída dos usuários, a obtenção de usuários representativos dos diversos perfis torna-se bastante difícil. Nos métodos tradicionais de avaliação, especialistas em usabilidade analisam a interação de cada usuário interagindo com a aplicação, para encontrar problemas de usabilidade. Esta análise depende do conhecimento e esforço desses especialistas para encontrar problemas na aplicação avaliada. Desse modo, os métodos tradicionais, se utilizados em grande escala de usuários, tornam-se demasiadamente caros devido a seus custos e tempo de execução. Outra característica importante das aplicações Web é sua constante evolução, o que necessita de avaliações de usabilidade periódicas e constantes, para verificar se alterações não prejudicam sua usabilidade. Da mesma forma, os métodos tradicionais de avaliação de usabilidade tornam-se demasiadamente caros, se utilizados em avaliações constantes da usabilidade de aplicações Web. Nesse contexto, esta tese buscou, na automatização do processo de avaliação de usabilidade, uma alternativa para diminuir as dificuldades mencionadas anteriormente em se avaliar a usabilidade de aplicações Web, especialmente em sua fase de manutenção. Assim, esta tese defende a hipótese de que, utilizando-se um método de avaliação de usabilidade fundamentado na captura e análise da interação de usuários de maneira remota e automatizada, é possível diminuir as dificuldades existentes nos métodos tradicionais na fase de manutenção de uma aplicação Web, possibilitando ainda: a análise da interação de usuários em campo e em grande escala de usuários; a identificação de padrões de interação dos usuários com a aplicação; uma avaliação com baixo custo de execução, favorecendo a realização de avaliações periódicas de usabilidade de uma aplicação Web. Neste sentido, esta tese apresenta o desenvolvimento do WebHint, um método remoto e automatizado de avaliação de usabilidade para aplicações Web. O método proposto nesta tese foi aplicado em três estudos de usabilidade que validaram o WebHint como uma alternativa viável para a realização de avaliações remotas e automatizadas de usabilidade de aplicações Web / Abstract: Observing users interacting with user interfaces is the basis of traditional usability evaluation methods as user tests and field observation. In spite of their popularity and efficiency in finding usability problems, these traditional methods are considered expensive, due to the costs of involving users in the evaluation, preparing the infrastructure and specially, due to the costs of executing the methods and analyzing the results. The quality of the results obtained with these methods depends on the users participating of the evaluation, who need to represent all the user's profiles of the evaluated application. In the Web, due to the diversity and distributed location of the users, it is difficult to obtain representative users. In traditional methods, usability experts analyze the behavior of each user interacting with the application in order to detect usability problems. This subjective analysis depends on the knowledge and work of the expert to find the problems. This way, the traditional methods became too expensive when it is necessary to involve high number of users in the evaluation. Another important aspect of Web applications is their frequent evolvement, which requires usability evaluations performed frequently to avoid usability problems caused by changes on the applications. The same way, the traditional methods are too expensive to be performed in a regular basis. In that context, this thesis proposes an automatic method for usability evaluation, as an alternative approach to deal with the difficulties mentioned above. This way, this thesis supports the hypothesis that is possible to decrease the difficulties regarding to the traditional methods through a usability evaluation method based on the automatic capture and analysis of user's interaction. Thus, this thesis, presents the development of the WebHint, a remote and automatic usability evaluation method for Web applications. The proposed method was applied in three usability studies, and their results validated the WebHint as a feasible alternative to perform remote and automatic usability evaluations of Web applications / Doutorado / Ciência da Computação / Doutor em Ciência da Computação
405

Mobile phones interaction techniques for second economy people

Edim, Azom Emmanuel January 2010 (has links)
Second economy people in developing countries are people living in communities that are underserved in terms of basic amenities and social services. Due to literacy challenges and user accessibility problems in rural communities, it is often difficult to design user interfaces that conform to the capabilities and cultural experiences of low-literacy rural community users. Rural community users are technologically illiterate and lack the knowledge of the potential of information and communication technologies. In order to embrace new technology, users will need to perceive the user interface and application as useful and easy to interact with. This requires proper understanding of the users and their socio-cultural environment. This will enable the interfaces and interactions to conform to their behaviours, motivations as well as cultural experiences and preferences and thus enhance usability and user experience. Mobile phones have the potential to increase access to information and provide a platform for economic development in rural communities. Rural communities have economic potential in terms of agriculture and micro-enterprises. Information technology can be used to enhance socio-economic activities and improve rural livelihood. We conducted a study to design user interfaces for a mobile commerce application for micro-entrepreneurs in a rural community in South Africa. The aim of the study was to design mobile interfaces and interaction techniques that are easy to use and meet the cultural preferences and experiences of users who have little to no previous experience of mobile commerce technology. And also to explore the potentials of information technologies rural community users, and bring mobile added value services to rural micro-entrepreneurs. We applied a user-centred design approach in Dwesa community and used qualitative and quantitative research methods to collect data for the design of the user interfaces (graphic user interface and voice user interface) and mobile commerce application. We identified and used several interface elements to design and finally evaluate the graphical user interface. The statistics analysis of the evaluation results show that the users in the community have positive perception of the usefulness of the application, the ease of use and intention to use the application. Community users with no prior experience with this technology were able to learn and understand the interface, recorded minimum errors and a high level of v precision during task performance when they interacted with the shop-owner graphic user interface. The voice user interface designed in this study consists of two flavours (dual tone multi-frequency input and voice input) for rural users. The evaluation results show that community users recorded higher tasks successes and minimum errors with the dual tone multi-frequency input interface than the voice only input interface. Also, a higher percentage of users prefer the dual tone multi-frequency input interface. The t-Test statistical analysis performed on the tasks completion times and error rate show that there was significant statistical difference between the dual tone multi-frequency input interface and the voice input interface. The interfaces were easy to learn, understand and use. Properly designed user interfaces that meet the experience and capabilities of low-literacy users in rural areas will improve usability and users‟ experiences. Adaptation of interfaces to users‟ culture and preferences will enhance information services accessibility among different user groups in different regions. This will promote technology acceptance in rural communities for socio-economic benefits. The user interfaces presented in this study can be adapted to different cultures to provide similar services for marginalised communities in developing countries
406

Implementation of a facebook crawler for opinion monitoring and trend analysis purposes: a case study of government service delivery in Dwesa

Mfenyana, Sinesihle Ignetious January 2014 (has links)
The Internet has shifted from the Web 1.0 era to the Web 2.0 era. In the contemporary era of web 2.0, the Internet is being used to build and reflect social relationships among people who share similar interests and activities. This is done through services such as Social Networking Sites (Facebook, Twitter etc.) and the web blogs. Currently, there is a very high usage of Social Networking Sites (SNSs) and blogs where people share their views, opinions, and thoughts. This leads to the production of a lot of data by people who post such content on SNSs. As a result, SNSs and blogs become the ideal platforms for opinion monitoring and the trend analysis. These SNSs and Blogs could be used by service providers for tracking what the public thinks or requires. The reason being, having such knowledge can help in decision making and future planning. If service providers can keep track of such views, opinions or thoughts with regard to the services they provide, they can better their understanding about the public or clients’ needs and improve the provision of relevant services. This research project presents a system prototype for performing opinion monitoring and trend analysis on Facebook. The proposed system crawl Facebook, indexes the data and provides user interface (UI) where end users can search and see the trending of a topics of their choice. The system prototype could also be used to check the trending topics without having to search. The main objective of this research project was to develop a framework that will contribute in improving the way government officials, companies or any service providers and normal citizens communicate regarding services they provide. This research project is premised on the conceptualization that if the government officials, companies or any service providers can keep track of the citizen’s opinions, views and thoughts with regards to services they provide it can help improve the delivery of such services. This research and the implementation of the trend analysis tool is undertaken in the context of the Siyakhula Living Lab (SLL), an Information and Communication Technologies for Development (ICTD) intervention for Dwesa marginalized community.
407

Learning in Partially Observable Markov Decision Processes

Sachan, Mohit 21 August 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Learning in Partially Observable Markov Decision process (POMDP) is motivated by the essential need to address a number of realistic problems. A number of methods exist for learning in POMDPs, but learning with limited amount of information about the model of POMDP remains a highly anticipated feature. Learning with minimal information is desirable in complex systems as methods requiring complete information among decision makers are impractical in complex systems due to increase of problem dimensionality. In this thesis we address the problem of decentralized control of POMDPs with unknown transition probabilities and reward. We suggest learning in POMDP using a tree based approach. States of the POMDP are guessed using this tree. Each node in the tree has an automaton in it and acts as a decentralized decision maker for the POMDP. The start state of POMDP is known as the landmark state. Each automaton in the tree uses a simple learning scheme to update its action choice and requires minimal information. The principal result derived is that, without proper knowledge of transition probabilities and rewards, the automata tree of decision makers will converge to a set of actions that maximizes the long term expected reward per unit time obtained by the system. The analysis is based on learning in sequential stochastic games and properties of ergodic Markov chains. Simulation results are presented to compare the long term rewards of the system under different decision control algorithms.
408

A comparison of geocoding baselayers for electronic medical record data analysis

Severns, Christopher Ray 16 January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Identifying spatial and temporal patterns of disease occurrence by mapping the residential locations of affected people can provide information that informs response by public health practitioners and improves understanding in epidemiological research. A common method of locating patients at the individual level is geocoding residential addresses stored in electronic medical records (EMRs) using address matching procedures in a geographic information system (GIS). While the process of geocoding is becoming more common in public health studies, few researchers take the time to examine the effects of using different address databases on match rate and positional accuracy of the geocoded results. This research examined and compared accuracy and match rate resulting from four commonly-used geocoding databases applied to sample of 59,341 subjects residing in and around Marion County/ Indianapolis, IN. The results are intended to inform researchers on the benefits and downsides to their selection of a database to geocode patient addresses in EMRs.
409

Optimising the usability of content rich e-learning material: an eye tracking experiment

Mpofu, Bongeka 11 1900 (has links)
This research was aimed at the optimisation of the usability of content-rich computer and mobile based e-learning material. The goal was to preserve the advantages of paper based material in designing optimised modules that were mobile and computer-based, but at the same time avoiding the pitfalls of converting traditional paper based learning material for use on screen. A mobile eye tracker was used to analyse how students studied similar course content on paper, and on mobile device. Screen based eye tracking was also used to analyse how participants studied corresponding content on a desktop screen. Eye movements which were recorded by an eye tracker revealed the sequences of fixations and saccades on the text that was read by each participant. By analysing and comparing the eye gaze patterns of students reading the same content on three different delivery platforms, the differences between these platforms were identified in terms of their delivery of content rich, text based study material. The results showed that more students read online content on a computer screen than on mobile devices. The inferential analysis revealed that the differences in reading duration, comprehension, linearity and fixation count on the three platforms were insignificant. There were significant differences in saccade length. This analysis was used to identify strong aspects of the respective platforms and consequently derive guidelines for using these aspects optimally to design content rich material for delivery on computer screen and mobile device. The limitations of each platform were revealed and guidelines for avoiding these were derived / Computing / M.A. (Computing)
410

Brain-computer interfaces for inducing brain plasticity and motor learning: implications for brain-injury rehabilitation

Babalola, Karolyn Olatubosun 08 July 2011 (has links)
The goal of this investigation was to explore the efficacy of implementing a rehabilitation robot controlled by a noninvasive brain-computer interface (BCI) to influence brain plasticity and facilitate motor learning. The motivation of this project stemmed from the need to address the population of stroke survivors who have few or no options for therapy. A stroke occurs every 40 seconds in the United States and it is the leading cause of long-term disability [1-3]. In a country where the elderly population is growing at an astounding rate, one in six persons above the age of 55 is at risk of having a stroke. Internationally, the rates of strokes and stroke-induced disabilities are comparable to those of the United States [1, 4-6]. Approximately half of all stroke survivors suffer from immediate unilateral paralysis or weakness, 30-60% of which never regain function [1, 6-9]. Many individuals who survive stroke will be forced to seek institutional care or long-term assistance. Clinicians have typically implemented stroke rehabilitative treatment using active training techniques such as constraint induced movement therapy (CIMT) and robotic therapy [10-12]. Such techniques restore motor activity by forcing the movement of weakened limbs. That active engagement of the weakened limb movement stimulates neural pathways and activates the motor cortex, thus inducing brain plasticity and motor learning. Several studies have demonstrated that active training does in fact have an effect on the way the brain restores itself and leads to faster rehabilitation [10, 13-15]. In addition, studies involving mental practice, another form of rehabilitation, have shown that mental imagery directly stimulates the brain, but is not effective unless implemented as a supplemental to active training [16, 17]. Only stroke survivors retaining residual motor ability are able to undergo active rehabilitative training; the current selection of therapies has overlooked the significant population of stroke survivors suffering from severe control loss or complete paralysis [6, 10]. A BCI is a system or device that detects minute changes in brain signals to facilitate communication or control. In this investigation, the BCI was implemented through an electroencephalograph (EEG) device. EEG devices detect electrical brain signals transmitted through the scalp that corresponded with imagined motor activity. Within the BCI, a linear transformation algorithm converted EEG spectral features into control commands for an upper-limb rehabilitative robot, thus implementing a closed-looped feedback-control training system. The concept of the BCI-robot system implemented in this investigation may provide an alternative to current therapies by demonstrating the results of bypassing motor activity using brain signals to facilitate robotic therapy. In this study, 24 able-bodied volunteers were divided into two study groups; one group trained to use sensorimotor rhythms (SMRs) (produced by imagining motor activity) to control the movement of a robot and the other group performed the 'guided-imagery' task of watching the robot move without control. This investigation looked for contrasts between the two groups that showed that the training involved with controlling the BCI-robot system had an effect on brain plasticity and motor learning. To analyze brain plasticity and motor learning, EEG data corresponding to imagined arm movement and motor learning were acquired before, during, and after training. Features extracted from the EEG data consisted of frequencies in the 5-35Hz range, which produced amplitude fluctuations that were measurably significant during reaching. Motor learning data consisted of arm displacement measures (error) produced during an motor adaptation task performed daily by all subjects. The results of the brain plasticity analysis showed persistent reductions in beta activity for subjects in the BCI group. The analysis also showed that subjects in the Non-BCI group had significant reductions in mu activity; however, these results were likely due to the fact that different EEG caps were used in each stage of the study. These results were promising but require further investigation. The motor learning data showed that the BCI group out-performed non-BCI group in all measures of motor learning. These findings were significant because this was the first time a BCI had been applied to a motor learning protocol and the findings suggested that BCI had an influence on the speed at which subjects adapted to a motor learning task. Additional findings suggested that BCI subjects who were in the 40 and over age group had greater decreases in error after the learning phase of motor assessment. These finding suggests that BCI could have positive long term effects on individuals who are more likely to suffer from a stroke and possibly could be beneficial for chronic stroke patients. In addition to exploring the effects of BCI training on brain plasticity and motor learning this investigation sought to detect whether the EEG features produced during guided-imagery could differentiate between reaching direction. While the analysis presented in this project produced classification accuracies no greater than ~77%, it formed the basis of future studies that would incorporate different pattern recognition techniques. The results of this study show the potential for developing new rehabilitation therapies and motor learning protocols that incorporate BCI.

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