Past studies have shown that the effects of selective auditory attention are evident in medial olivocochlear (MOC) activity, manifested as the contralateral suppression (CS) of transient evoked otoacoustic emissions (TEOAEs). This finding suggests the use of TEOAEs in the design of an auditory-based access technology as a potential access solution for children with severe disabilities. Thirteen participants with normal hearing threshold and normal middle ear function completed this study. The participants were instrumented with a TEOAE ear probe and presented with a contralateral acoustic stimulus. They were instructed to alternate auditory attention conditions as visually cued by symbols on an LCD display. Attentive and non-attentive conditions were detected with an overall accuracy of 70.17 +/- 12.54% at 2.44 +/- 0.3 bits per minute in a participant-specific classifier, and 65.92 +/- 13.91% in a participant-independent classifier. Detection of auditory attention exceeded random chance levels for 11 of 13 participants.

This article provides an overview of Internet shutdowns in Pakistan, which have become an increasingly common phenomenon, with 41 occurring between 2012 and 2017. It argues that to understand how shutdowns became normalized in Pakistan, it is necessary to look at the specific dynamics of how the shutdowns take place. In doing so, the concept of communicative ruptures develops to better understand intentional government shutdowns of communications. The article argues that strategic prevention of mobilization is key for short-term shutdowns, whereas long-term shutdowns can be better explained by looking at disciplinary mechanisms and denying the existence of "others". The article then discusses Internet shutdowns in the wider context of authoritarian practices before concluding with the urgent need for further research on this topic, both in Pakistan and beyond.

The widespread integration of the computer into the mainstream of daily life presents a challenge to various sectors of society, and the incorporation of this technology into the realm of the older individual with visual impairments is a relatively uncharted field of study. This study was undertaken to acquire the perceptions of the impact of the training and issuance of the access of technology upon participants’ quality of life. The study adopted a qualitative research approach employing phenomenological, descriptive, and cross-case components in order to understand the experience of older (over 40) veterans who were legally blind, had completed Computer Access Technology (CATS) training, and had been issued assistive technology. The 9 respondents were selected from veterans who had been through the CATS program and were known to the researcher in an attempt to maximize the range of ages, military experience, and origin of vision loss. This study employed semi-structured interviews that were recorded and later transcribed verbatim. Through content analysis, the participants’ responses, originally in 20 categories, were consolidated into 3 categories, which correlated to the questions of this study. During this process, an emergent category, “Background and History of the Participants,” evolved, resulting in a total of 4 categories. The categories reflected the background and history of participants, the impact of blind rehabilitation, current computer usage in daily tasks, and participants’ comments and recommendations. The results demonstrated that the CATS training had a profound impact on the participants upon their return to their homes. The impact included the restored ability to communicate with family and friends, the development of new interests and abilities, the re-establishment of self-worth, a sense of independence, and the feeling of being normal and not a “freak.” 7 of the 9 participants had already returned for additional CATS training during the research process. Of the remaining 2, 1 received on-the-job training, and the final participant would consider returning if his vision deteriorated. Various participants had returned or remained in the workforce, and others performed volunteer work. 6 envision further study through correspondence courses, more CATS training or on their own.

Functional neuroimaging techniques such as near-infrared spectroscopy (NIRS) have been studied in brain-computer interface (BCI) development. Previous research has suggested that the addition of a second brain-monitoring modality may improve the accuracy of a NIRS-BCI. The objective of this study was to determine whether the classification accuracies achievable by a multimodal BCI, which combines NIRS and transcranial Doppler ultrasonography (TCD) signals, can exceed those attainable using a unimodal NIRS-BCI or TCD-BCI. Nine able-bodied subjects participated in the study. Simultaneous measurements were made with NIRS and TCD instruments while participants were prompted to perform a verbal fluency task or to remain at rest, within the context of a block-stimulus paradigm. In five of nine (55.6%) participants, classification accuracies with the NIRS-TCD system were significantly higher (p<0.05) than with NIRS or TCD systems alone. Our results suggest that multimodal neuroimaging may be a promising approach towards improving the accuracy of future BCIs.

Functional neuroimaging techniques such as near-infrared spectroscopy (NIRS) have been studied in brain-computer interface (BCI) development. Previous research has suggested that the addition of a second brain-monitoring modality may improve the accuracy of a NIRS-BCI. The objective of this study was to determine whether the classification accuracies achievable by a multimodal BCI, which combines NIRS and transcranial Doppler ultrasonography (TCD) signals, can exceed those attainable using a unimodal NIRS-BCI or TCD-BCI. Nine able-bodied subjects participated in the study. Simultaneous measurements were made with NIRS and TCD instruments while participants were prompted to perform a verbal fluency task or to remain at rest, within the context of a block-stimulus paradigm. In five of nine (55.6%) participants, classification accuracies with the NIRS-TCD system were significantly higher (p<0.05) than with NIRS or TCD systems alone. Our results suggest that multimodal neuroimaging may be a promising approach towards improving the accuracy of future BCIs.

Las redes inal´ambricas actuales exhiben caracter´ısticas heterog´eneas de acceso m´ultiple mediante el despliegue, la coexistencia y la cooperaci´on de varias Tecnolog ´ıas de Acceso Radio (RAT2). En este escenario, la prestaci´on de servicios multimedia garantizando una cierta calidad de servicio (QoS3) es obligatoria. El objetivo global de las redes heterog´eneas de acceso inal´ambrico consiste en sustentar la realizaci´on del concepto ABC (del ingl´es Always Best Connected), en el que un usuario est´a siempre conectado a la RAT que mejor satisface sus necesidades de servicio en cualquier momento, en cualquier lugar, de cualquier modo. En este sentido, las estrat´egias de gesti´on de recursos radio comunes [del ingl´es, Common Radio Resource Management (CRRM)] se dise˜nan para proporcionar una utilizaci´on eficiente de los recursos radio y de espectro radioel´ectrico dentro de la red heterog´enea, ofreciendo un mejor rendimiento en comparaci´on con la realizaci´on independiente de RRM en cada RAT. Adem´as, los recursos de espectro asignados a cada una de las RATs deben ser utilizado de manera eficiente, ya que se trata de un recurso escaso y costoso. En este sentido, conceptos y metodolog´ıas de radio cognitiva (del ingl´es Cognitive Radio o CR) se han aplicado a la gesti´on del espectro, permitiendo una compartici´on dinamico-oportunista del mismo. En estos casos, el espectro sujeto a licencia se abre hacia el acceso de usuarios sin licencia siempre que no perjudiquen y que el funcionamiento libre de interferencias est´e garantizado. Esta tesis analiza estrategias de gesti´on de recursos radio y de espectro para ofrecer un uso mayor y eficiente de los escasos recursos radio y de espectro con el objetivo final de aumentar al m´aximo la capacidad de usuario, garantizando los requerimientos de QoS. En concreto, estas tesis se centra primero en como seleccionar una RAT al inicio de una llamada/sesi´on (en adelante, selecci´on inicial de RAT) en una red de acceso heterog´enea. Un modelo de Markov ha sido desarrollado para definir la asignaci´on de m´ultiples servicios (multi-servicio) en m´ultiples RATs (multi-acceso). En este marco, varias pol´ıticas de selecci´on de RAT son propuestas y evaluadas, gen´ericamente clasific´andose en pol´ıticas basadas en servicio (SB4) y basadas en balanceo de carga (LB5). Adem´as, el rendimiento de las pol´ıticas de selecci´on de RATs en escenarios de acceso limitado debido a la deficiente cobertura radio, la falta de disponibilidad de terminales multi-modo y la incompatibilidad entre RAT y servicios tambi´en es evaluada. Principios espec´ıficos para la asignaci´on de servicios a RATs ser´an provistos en los escenarios antes mencionados con el objetivo general de aumentar la capacidad de usuarios, garantizando los requisitos m´ınimos de calidad de servicio. Finalmente, la congesti´on en el acceso radio tambi´en se trata en este escenario multi-acceso/multi-servicio y el impacto de la selecci´on de RAT evaluado. Los principios para la asignaci´on inicial de RAT con tal de evitar la congesti´on radio ser´an tambi´en proporcionados. En segundo lugar, esta tesis investiga sobre la forma de maximizar el uso eficiente del espectro sujeto a licencia (o licenciado) por medio del acceso din´amicooportunista de espectro a usuarios sin licencia. En este sentido, se concibe un modelo de Markov para captar el problema del uso compartido de espectro entre usuarios con y sin licencia. Un modelo basado en sensado de espectro se propone con el fin de detectar porciones de espectro no utilizados (en ingl´es white spaces) que pueden ser usados por los usuarios sin licencia mientras este siga libre. En este marco, los beneficios obtenidos de la compartici´on del espectro son investigados y las ventajas que implican evaluadas. En concreto, se eval´ua el rendimiento obtenido al ajustar el punto de funcionamiento (en ingl´es operating point ) del mecanismo de sensado, el cual determina los errores de no-detecci´on y falsa-alarma. Por otra parte, sistemas de canalizaci´on de espectro fijos versus adaptativos ser´an propuestos y analizados bajo dos disciplinas de servicio diferentes, cuya duraci´on (o tiempo de permanencia en el sistema) esta basada en tiempo y en contenido respectivamente. / Current wireless networks exhibit heterogeneous multi-access features by means of the coexisting and cooperative deployment of several Radio Access Technologies (RATs). In this scenario, the provision of multimedia services with ensured Quality of Service (QoS) is mandatory. The overall goal of heterogeneous wireless access networks is to enable the realization of the Always Best Connected concept in which a user is seamlessly connected to the RAT best suiting its service requirements anytime, anywhere, anyhow. In this sense, Common Radio Resource Management (CRRM) strategies are devoted to provide an efficient utilization of radio resources within the heterogeneous network offering improved performances as opposed to performing stand-alone RRM in each RAT. In addition, allocated spectrum resources to each RAT must be efficiently utilized since it is a scarce and expensive resource. In this respect, cognitive radio concepts and methodologies have been applied to spectrum management by enabling dynamic/opportunistic spectrum sharing. In these scenarios, licensed spectrum is opened towards unlicensed access provided a non-harmful operation is guaranteed. This dissertation discusses both radio resource and spectrum management strategies to provide an utmost and efficient use of scarce radio/spectrum resources with the overall goal of maximizing user capacity while guaranteeing QoS constraints.Specifically, the thesis is first focused on how to select an appropriate RAT upon call/session initiation (henceforth, initial RAT selection) in a heterogeneous access network. A Markovian framework is developed to such extent supporting the allocation of multiple service-type users (multi-service) on multiple RATs (multi-access). Under this framework, several RAT selection policies are proposed and evaluated, broadly categorized into service-based (SB) and load-balancing (LB). In addition, the performance of RAT selection policies in access-limited scenarios due to poor radio coverage, non multi-mode terminal availability and RAT-service incompatibility is also evaluated. Specific guiding principles for the allocation of services on several RATs are provided in the abovementioned scenarios with the overall goal of increasing user capacity while guaranteeing minimum QoS requirements. Finally, radio access congestion is also addressed in this multi-access/multi-service scenario and the impact RAT selection assessed. Suitable allocation principles avoiding congestion are also provided.Secondly, this dissertation investigates on how to efficiently maximize the use of licensed spectrum by means of dynamic/opportunistic unlicensed spectrum access. Hereof, a Markovian framework is also devised to capture the problem of licensed spectrum sharing towards unlicensed users. A sensing-based spectrum awareness model is proposed in order to detect unused spectrum (so-called white spaces) which may be accessed by unlicensed users while remaining unused. Under this framework, the benefits of spectrum sharing are investigated and the involved gains assessed. Specifically, the sensing-throughput tradeoff and the adjustment of the sensing mechanism’s operating point, which tradeoffs missed-detection and false-alarm errors, is evaluated. Moreover, fixed vs. adaptive spectrum channelization schemes are proposed and analyzed under two different service disciplines considering time-based and volume-based content delivery.

This study investigated the perceptions of students, the instructor and the laboratory assistant about the use of remote access technology in group projects of programming language courses. Their perceptions are investigated in terms of three aspects: effects of the use of this technology on their motivation, the perceived usefulness and the perceived ease of use of this technology. A central shared project server was installed for group project studies of students. To access to the central project server, Microsoft Remote Desktop Connection, which is a remote access technology, was used. The data were collected from 2nd grade university students by using a computer attitude scale and a questionnaire developed by the researcher. Also, interviews were conducted with the course instructor and the laboratory assistant. Descriptive statistics, frequency distributions and descriptive analysis methods were used to analyze the results. In results, the high percentage of indecisive students, which is between 38% and 48%, was noticeable. It was concluded that by increasing the length of usage of the system this high ratio may be decreased to reasonable levels. On the other hand, high number of the rest of the students reported positive perceptions. They expressed that remote access technology is a useful and also easy to use technology. It is concluded that students, the instructor and the laboratory assistant accepted the use of this new technology in their learning environment. Also, like instructor and the laboratory assistant, they stated that it affected their motivation towards the group projects in a positive way.

Although Indonesia’s electrification ratio reached 99.2% in 2020, it has shown stagnating electrification since 2018. This is because most of the remaining areas that need to be electrified are remote and have unique characteristics that hamper implementation of microgrids for providing energy access. Furthermore, not only the deployment but also the long-term sustainability of microgrids is crucial for ensuring continuity of energy access. This paper aims to investigate the scaling and sustainability challenges of remote microgrid development in Indonesia by analyzing microgrids in the Maluku and North Maluku provinces. This study is a two-part publication; the first part focuses on identifying challenges in Indonesia’s remote microgrid development, while the second part focuses on potential technology solutions. In the first part, an assessment of energy access within a multi-tier framework was conducted, which was then analyzed using a multi-dimensional (institutional, social, technical, economic, environmental, and policy) approach adapted from the literature. The framework was expanded by mapping the challenges onto specific phases of the microgrid development, which is intended to be helpful for the parties involved in specific phases. It is shown that the challenges related to unclear land status, lack of social engagement, preliminary survey, technical and practical knowledge, and O&M procedures—especially for remote microgrids with renewable energy sources—are the most prominent issues. Additionally, issues caused by electrical events and environmental conditions such as relatively humid and high-temperatures, and uncontrolled vegetation, rodents, insects, and lizards are often found. Furthermore, a high-level technological outlook to address some of these issues is presented.

The purpose of this thesis was to explore the potential of near-infrared spectroscopy (NIRS) as an access channel by establishing reliable signal detection to verify the existence of signal differences associated with changes in activity. This thesis focused on using NIRS to measure brain activity from the prefrontal cortex during an auditory Go-No-Go task. A singular spectrum analysis change-point detection algorithm was applied to identify transition points where the NIRS signal properties varied from previous data points in the signal, indicating a change in brain activity. With this algorithm, latency values for change-points detected ranged from 6.44 s to 9.34 s. The averaged positive predictive values over all runs were modest (from 49.41% to 67.73%), with the corresponding negative predictive values being generally higher (48.66% to 78.80%). However, positive and negative predictive values up to 97.22% and 95.14%, respectively, were achieved for individual runs. No hemispheric differences were found.

The purpose of this thesis was to explore the potential of near-infrared spectroscopy (NIRS) as an access channel by establishing reliable signal detection to verify the existence of signal differences associated with changes in activity. This thesis focused on using NIRS to measure brain activity from the prefrontal cortex during an auditory Go-No-Go task. A singular spectrum analysis change-point detection algorithm was applied to identify transition points where the NIRS signal properties varied from previous data points in the signal, indicating a change in brain activity. With this algorithm, latency values for change-points detected ranged from 6.44 s to 9.34 s. The averaged positive predictive values over all runs were modest (from 49.41% to 67.73%), with the corresponding negative predictive values being generally higher (48.66% to 78.80%). However, positive and negative predictive values up to 97.22% and 95.14%, respectively, were achieved for individual runs. No hemispheric differences were found.