Abstract An inevitable trend in wireless communications is the requirement for higher and higher data rates. At the same time, location awareness requires high accuracy for positioning ability. One option fulfilling both of these challenges is the use of an ultra wideband (UWB) physical layer technology due to its extremely large inherent bandwidth. From the two possible solutions to generate UWB signals, this thesis is focused on the singleband approach. This technique is closer to the original idea of impulse radio transmission than the other recently proposed multiband UWB approach. This thesis focuses on UWB coexistence with several selected radio systems; global positioning and cellular systems, and wireless local area networks. The topic was studied analytically and with experimental tests. The analytical part is divided into simulations and theoretical calculations. In the study, two different physical layer concepts, several modulation schemes and pulse waveforms have been used to find the best system performance under interference. From time hopping and direct sequence based approaches (TH and DS, respectively), the latter with binary pulse amplitude modulation was seen to outperform the former one in an interfered multipath channel if compared with bit error rate performance. Therefore, the theoretical calculations are addressed to the DS-UWB approach. The formulation defined makes it possible to rather easily calculate the upper bound for DS-UWB system performance in an AWGN channel and the results can be used to calculate reference bounds, for example, in receiver algorithm studies. The experimental part of the work focused on link level coexistence measurements between UWB and either IEEE802.11b or 3G networks. UWB can cause harmful performance degradation on the victim system if there are unrealistic numbers of active interferers in close vicinity of the victim receiver. However, increasing the separation between the UWB interferer and victim to 40 cm, or 70 cm, in the case of WLAN and 3G, respectively, the impact is insignificant. It was also shown that the activity factor of the UWB transmitter has a great impact on the victim system's performance degradation. UWB activity factors of less than about 5% can be tolerated by the studied victim systems.

<p>CAL (Computer Assisted Learning) programs are widespread today in schools and families due to the effectiveness of CAL programs in improving students’ learning and task performance. The flourishing of CAL programs in education has brought large amounts of students’ learning data including log data, performance data, mouse movement data, eye movement data, video data, etc. These data can present students’ learning or problem-solving processes and reflect underlying cognitive processes. These data are valuable resources for educators to comprehend students’ learning and difficulties. However, few data analysis methods can analyze and present CAL data for educators quickly and clearly. Traditional video analysis methods can be time-consuming. Current visualization analysis methods are limited to simple charts or visualizations of a single data type. In this dissertation, I propose a visual learning analytic approach to analyze and present students' problem-solving data from CAL programs. More specifically, a visualization system was developed to present students’ problem-solving data, including eye movement, mouse movement, and performance data, to help educational researchers understand student problem-solving processes and identify students’ problem-solving strategies and difficulties. An evaluation experiment was conducted to compare the visualization system with traditional video analysis methods. Seven educational researchers were recruited to diagnose students’ problem-solving patterns, strategies, and difficulties using either the visualization system or video. The diagnosis task loads and evaluators’ diagnosis processes were measured and the evaluators were interviewed. The results showed that analyzing student problem-solving tasks using the proposed visualization method was significantly quicker than using the video method. In addition, diagnosis using the visualization system can achieve results at least as reliable as the video analysis method. Evaluators’ preferences between the two methods are summarized and illustrated in the dissertation. Finally, the implications of the visual analytic approach in education and data visualization areas are discussed. </p>

The term “IoT” has evolved to encompass a wide range of diffuse concepts, but the common thread among the myriad definitions has been the convergence of technology to bring <i>advanced conveniences</i> to our every day, but complicated, lives. A long-term focus of the Collaborative Robotics Lab, and a particular focus of many with interests in consumer assistance, has been the kitchen, which acts as the “nerve center” of the home in many cultures. However, despite the grand vision of revolutionizing the kitchen and improving our lifestyles with technology, what today’s IoT-integrated appliances and kitchen-focused conveniences offer is mainly limited to a remote control. While remote control is certainly convenient, it still requires human planning in both cognitive and physical loads in performing cooking activities. The goal of this thesis is to build a framework of the network of IoT-enabled kitchen appliances, <i>TupperwareEarth</i> for the “Internet of Kitchen Things” integrated with an inference engine that utilizes ontology as a knowledge database. From simple clustering of sensor data to recommender systems that employ crowd-sourced preference data, the cognitive burden is reduced with proactive suggestions to high-level queries based upon the current kitchen state. Through the progression of the studies in the “Internet of Kitchen Things,” <i>TupperwareEarth </i>aims to reduce human planning that involves both cognitive and physical loads of burden by inferring solutions to the activities of daily kitchen living using ontological semantics.

Today a growing number of people need to work on laptops with wireless Internet connection. There are two common wireless Internet access solutions: wireless local area network (WLAN) via hotspot, and high speed wide area cellular network via mobile broadband device such as 3G/4G Universal Serial Bus (USB) dongle. USB dongle was the pioneer product in 3G/4G market, and it is still a popular device in many countries. Mobile broadband can offer both high speed access and mobility. Technically mobile broadband allows Internet connection as long as your mobile transceiver can access your cellular network operator’s network. However, in practice the data rates experienced by a user via mobile broadband are not comparable to the data rates that are available via WLAN. Moreover, mobile broadband has been implemented according to multiple different standards. Hence, in order to provide a user with locally optimal service requires that user must make use of heterogeneous networks. Furthermore, the variety of networks gets increasing due to the emergence of various 4G networks. The aim of this thesis is to explore how heterogeneous networks could be exploited to provide a user of a laptop computer with locally optimal service, while hiding the complexity of this heterogeneous service. The research focuses on the implications of integrating multiple network interfaces into a single USB dongle. Our research shows that multi-mode USB dongle is still needed in market, though there are competitions from smartphones and mobile WiFi devices. We point out that the PPP (Point to Point Protocol) based USB dongle should update to Ethernet USB protocols such as RNDIS (Remote Network Driver Interface Specification) or USB CDC (Communications Device Class) protocols. Furthermore, we suggest a USB dongle should be able to work as a WLAN access point to share Internet with other mobile devices, and it should also work as a WLAN client which can join other hotspots. If hotspot operators can authenticate USB dongles by SIM cards, then users can easily access a great number of hotspots belong to these operators. / Mer än någonsin behöver människan arbeta med bärbara datorer med anslutning till trådlöst Internet. Det finns två vanliga trådlösa Internet-anslutningar: trådlöst lokalt nätverk (WLAN på engelska) via en hotspot, eller höghastighets mobilnät via mobilt bredband som 3G/4G Universal Serial Bus (USB) dongel. USB dongeln var pionjär produkten inom 3G/4G marknaden, och den är fortfarande en populär enhet i många länder. Mobilt bredband kan erbjuda både tillgång till höga hastighet och bra mobilitet. Mobilt bredband tillåter, rent tekniskt, användaren hålla en Internet-anslutning så länge mobilen har tillgång till mobilnätets operatörsnät. Men i praktiken är datahastigheterna, som användaren upplever ha via det mobila bredbandet, inte jämförbar med de datahastigheter som är tillgängliga via WLAN. Dessutom har mobilt bredband implementerats enligt flera olika standarder. Således, för att förutse en användare med en optimal lokal tjänst, krävs det att användaren måste använda heterogena nätverk. Dessutom blir olika nätverk allt större på grund av uppkomsten av olika 4G-nät. Syftet med denna avhandling är att undersöka hur heterogena nätverk skulle kunna utnyttjas för att förutse en laptop användare med optimal lokal nätverksservice, samtidigt dölja komplexiteten för användaren om den heterogena tjänsten. Forskningen fokuserar på konsekvenserna av att integrera flera nätverksgränssnitt till en enda USB-dongel. Vår forskning visar att det fortfarande behövs en multi-mode USB dongel på marknaden, dock existerar det konkurrens från smartphones och mobila WiFi-enheter. Vi påpekar även i avhandlingen att PPP (Point-to-Point Protocol) baserade USB dongeln bör uppdateras till Ethernet USB-protokoll, såsom RNDIS (Remote Network Driver Interface Specification) eller USB CDC (Communications Device Class) protokoll. Vidare föreslår vi att en USB-dongel bör kunna fungera som en kopplingspunkt för att dela Internet med andra mobila enheter, och att den också bör fungera som en WLAN-klient som kan ansluta sig till andra hotspots. Om hotspot operatörer kan autentisera USB-donglar genom SIM-kort, så kan användarna enkelt få tillgång till ett stort antal hotspots som tillhör dessa operatörer.

<p>The web and digital technologies have been continuously growing in the recent five years. The data generated from the Internet of Things (IoT) devices are heterogeneous, increasing data storage and management difficulties. The thesis developed user-friendly data management system frameworks in the local environment and cloud platform. The two frameworks applied to two applications in the industrial field: the agriculture informatics system and the personal healthcare management system. The systems are capable of information management and two-way communication through a user-friendly interface. </p>

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / NASA and the Air Force are increasing the number of hypersonic and access-to-space programs creating a growing requirement for flight test ranges over large regional areas. A principal challenge facing these extended test ranges is the ability to provide continuous vehicle communications by filling the gaps in coverage between fixed ground stations. Consequently, there is a need for mobile range systems that provide a multitude of communication services under varying circumstances. This paper discusses the functional design and systems capabilities, as well as the mission support criteria, concerning NASA’s Mobile Operations Facility (MOF). The MOF will be deployed to Dugway Proving Grounds (DPG), Utah, in support of the X-33 single-stage-to-orbit (SSTO) demonstrator.

Uma das premissas fundamentais em redes fotônicas baseadas na tecnologia de multiplexação por comprimento de onda (WDM) é o controle dos caminhos ópticos. Um caminho óptico, ou caminho de luz, é uma conexão puramente óptica estabelecida entre dois nós da rede, que pode atravessar diversos nós intermediários. Para dar suporte eficiente à demanda exigida de uma rede WDM sobre a qual executam aplicações de alto desempenho, os caminhos ópticos devem ser estabelecidos e encerrados dinamicamente, de tal forma que as rotas e os comprimentos de onda escolhidos minimizem a probabilidade de ocorrência de bloqueios de conexão por falta de recursos disponíveis. O elemento central de uma rede WDM é o sistema que controla os comutadores ópticos, determina as rotas, aloca os comprimentos de onda, e estabelece, mantém e encerra as conexões ópticas entre os nós da rede. O objetivo deste trabalho é apresentar estratégias de roteamento e de atribuição de comprimentos de onda para redes fotônicas usando heurísticas baseadas em inteligência de enxame. Os resultados demonstram que as estratégias desenvolvidas apresentam baixa probabilidade de bloqueio de requisições e buscam, sempre que possível, os caminhos de menor custo. As estratégias desenvolvidas levam em conta o dinamismo da rede, sendo as decisões de caminho baseadas em dados atualizados em cada nó da rede em tempo real, sem a necessidade do conhecimento global do estado da rede em cada nó. / A fundamental aspect of photonic networks based on wavelength division multiplexing (WDM) technology is the control of optical paths. An optical path, or lightpath, is a purely optical connection established between two network nodes, which can pass through several intermediate nodes. To efficiently support the demands required from a WDM network that runs high performance applications, the optical paths should be established and finished dynamically, in such a way that the selected routes and wavelengths tend to minimize the blocking probability due to the lack of available resources. The central element of a WDM network is the system that controls the optical switches, determines routes, allocates the wavelengths, and establishes, maintains and finishes connections between optical network nodes. The purpose is to present strategies for routing and wavelength assignment over photonic networks using heuristics based on swarm intelligence. Results show that the developed strategies exhibit low blocking probability of requests and find the paths of minimum cost whenever possible. The strategies developed take into account the dynamics of the network, and decisions are based on updated data at each network node in real time without the need of a complete knowledge of network state at each node.

Uma das premissas fundamentais em redes fotônicas baseadas na tecnologia de multiplexação por comprimento de onda (WDM) é o controle dos caminhos ópticos. Um caminho óptico, ou caminho de luz, é uma conexão puramente óptica estabelecida entre dois nós da rede, que pode atravessar diversos nós intermediários. Para dar suporte eficiente à demanda exigida de uma rede WDM sobre a qual executam aplicações de alto desempenho, os caminhos ópticos devem ser estabelecidos e encerrados dinamicamente, de tal forma que as rotas e os comprimentos de onda escolhidos minimizem a probabilidade de ocorrência de bloqueios de conexão por falta de recursos disponíveis. O elemento central de uma rede WDM é o sistema que controla os comutadores ópticos, determina as rotas, aloca os comprimentos de onda, e estabelece, mantém e encerra as conexões ópticas entre os nós da rede. O objetivo deste trabalho é apresentar estratégias de roteamento e de atribuição de comprimentos de onda para redes fotônicas usando heurísticas baseadas em inteligência de enxame. Os resultados demonstram que as estratégias desenvolvidas apresentam baixa probabilidade de bloqueio de requisições e buscam, sempre que possível, os caminhos de menor custo. As estratégias desenvolvidas levam em conta o dinamismo da rede, sendo as decisões de caminho baseadas em dados atualizados em cada nó da rede em tempo real, sem a necessidade do conhecimento global do estado da rede em cada nó. / A fundamental aspect of photonic networks based on wavelength division multiplexing (WDM) technology is the control of optical paths. An optical path, or lightpath, is a purely optical connection established between two network nodes, which can pass through several intermediate nodes. To efficiently support the demands required from a WDM network that runs high performance applications, the optical paths should be established and finished dynamically, in such a way that the selected routes and wavelengths tend to minimize the blocking probability due to the lack of available resources. The central element of a WDM network is the system that controls the optical switches, determines routes, allocates the wavelengths, and establishes, maintains and finishes connections between optical network nodes. The purpose is to present strategies for routing and wavelength assignment over photonic networks using heuristics based on swarm intelligence. Results show that the developed strategies exhibit low blocking probability of requests and find the paths of minimum cost whenever possible. The strategies developed take into account the dynamics of the network, and decisions are based on updated data at each network node in real time without the need of a complete knowledge of network state at each node.

In this dissertation, routing protocols, load-balancing protocols, and efficient evaluation techniques for multi-hop mobile wireless networks are explored. With the advancements made in wireless communication and computer technologies, a new type of mobile wireless network, known as a mobile ad hoc network (MANET), has drawn constant attention. In recent years, several routing protocols for MANETs have been proposed. However, there still remains the need for mechanisms for better scalability support with respect to network size, traffic volume, and mobility. To address this issue, a new method for multi-hop routing in MANETs called Dynamic NIx-Vector Routing (DNVR) is proposed. DNVR has several distinct features compared to other existing on-demand routing protocols, which lead to more stable routes and better scalability. Currently, ad hoc routing protocols lack load-balancing capabilities. Therefore they often fail to provide good service quality, especially in the presence of a large volume of network traffic since the network load concentrates on some nodes, resulting in a highly congested environment. To address this issue, a novel load-balancing technique for ad hoc on-demand routing protocols is proposed. The new method is simple but very effective in achieving load balance and congestion alleviation. In addition, it operates in a completely distributed fashion. To evaluate and verify wireless network protocols effectively, especially to test their scalability properties, scalable and efficient network simulation methods are required. Usually simulation of such large-scale wireless networks needs a long execution time and requires a large amount of computing resources such as powerful CPUs and memory. Traditionally, to cope with this problem, parallel network simulation techniques with parallel computing capabilities have been considered. This dissertation explores a different type of method, which is efficient and can be achieved with a sequential simulation, as well as a parallel and distributed technique for large-scale mobile wireless networks.

<p>This dissertation details one of the first lines of inquiry into the rhetorical strategies used in scientific data analysis. The study primarily concerns the relationships between data work and knowledge making in the analysis of so-called “big data,” and how rhetoric and technical communication theories might inform those relationships. Hinging on five months embedded at a national science laboratory, this study uses ethnographic methods to detail the ways in which data analysis is neither purely data-driven and objective, nor purely situated in a local context or problem. Rather, data work requires both analytical processes and artful <i>techne</i> embedded in ongoing reflective praxis. As purely analytic, data work focuses on mathematical treatments, step by step procedures and rote formulas. As <i>techne</i>, data work requires interpretation. Rhetorical data analysis is not the opposite of data-driven work. Instead, rhetorical <i>techne</i> stands as the midpoint between the extremes of purely data-driven and purely context-driven analysis. Based on three cases that compare the practices of data novices, seasoned experts, and interdisciplinary teams, I argue that the ways in which scientists go about their data cleaning, collaboration, and analysis change based on their levels of expertise and the problem at hand. A number of principles that outline how data analysis is a form of rhetorical inscription are also defined, including the ways data dictionaries, model building and the construction of proxies intimately link scientific insights with language. The set of principles detailed in this dissertation are key areas that should be considered in both data science education and professional and technical writing curricula. Therefore, the project should be of particular interest to instructors and administrators in both Technical Writing and Data Science programs, as well as well as critical data studies scholars.</p>