327 research outputs found

    Software-Defined Lighting.

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    For much of the past century, indoor lighting has been based on incandescent or gas-discharge technology. But, with LED lighting experiencing a 20x/decade increase in flux density, 10x/decade decrease in cost, and linear improvements in luminous efficiency, solid-state lighting is finally cost-competitive with the status quo. As a result, LED lighting is projected to reach over 70% market penetration by 2030. This dissertation claims that solid-state lighting’s real potential has been barely explored, that now is the time to explore it, and that new lighting platforms and applications can drive lighting far beyond its roots as an illumination technology. Scaling laws make solid-state lighting competitive with conventional lighting, but two key features make solid-state lighting an enabler for many new applications: the high switching speeds possible using LEDs and the color palettes realizable with Red-Green-Blue-White (RGBW) multi-chip assemblies. For this dissertation, we have explored the post-illumination potential of LED lighting in applications as diverse as visible light communications, indoor positioning, smart dust time synchronization, and embedded device configuration, with an eventual eye toward supporting all of them using a shared lighting infrastructure under a unified system architecture that provides software-control over lighting. To explore the space of software-defined lighting (SDL), we design a compact, flexible, and networked SDL platform to allow researchers to rapidly test new ideas. Using this platform, we demonstrate the viability of several applications, including multi-luminaire synchronized communication to a photodiode receiver, communication to mobile phone cameras, and indoor positioning using unmodified mobile phones. We show that all these applications and many other potential applications can be simultaneously supported by a single lighting infrastructure under software control.PhDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/111482/1/samkuo_1.pd

    A novel method to assess human population exposure induced by a wireless cellular network

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    <p>This paper presents a new metric to evaluate electromagnetic exposure induced by wireless cellular networks. This metric takes into account the exposure induced by base station antennas as well as exposure induced by wireless devices to evaluate average global exposure of the population in a specific geographical area. The paper first explains the concept and gives the formulation of the Exposure Index (EI). Then, the EI computation is illustrated through simple phone call scenarios (indoor office, in train) and a complete macro urban data long-term evolution scenario showing how, based on simulations, radio-planning predictions, realistic population statistics, user traffic data, and specific absorption rate calculations can be combined to assess the index.</p

    Easing the Transition from Inspiration to Implementation: A Rapid Prototyping Platform for Wireless Medium Access Control Protocols

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    Packet broadcast networks are in widespread use in modern wireless communication systems. Medium access control is a key functionality within such technologies. A substantial research effort has been and continues to be invested into the study of existing protocols and the development of new and specialised ones. Academic researchers are restricted in their studies by an absence of suitable wireless MAC protocol development methods. This thesis describes an environment which allows rapid prototyping and evaluation of wireless medium access control protocols. The proposed design flow allows specification of the protocol using the specification and description language (SDL) formal description technique. A tool is presented to convert the SDL protocol description into a C++ model suitable for integration into both simulation and implementation environments. Simulations at various levels of abstraction are shown to be relevant at different stages of protocol design. Environments based on the Cinderella SDL simulator and the ns-2 network simulator have been developed which allow early functional verification, along with detailed and accurate performance analysis of protocols under development. A hardware platform is presented which allows implementation of protocols with flexibility in the hardware/software trade-off. Measurement facilities are integral to the hardware framework, and provide a means for accurate real-world feedback on protocol performance

    Medium Access Control Layer Implementation on Field Programmable Gate Array Board for Wireless Networks

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    Triple play services are playing an important role in modern telecommunications systems. Nowadays, more researchers are engaged in investigating the most efficient approaches to integrate these services at a reduced level of operation costs. Field Programmable Gate Array (FPGA) boards have been found as the most suitable platform to test new protocols as they offer high levels of flexibility and customization. This thesis focuses on implementing a framework for the Triple Play Time Division Multiple Access (TP-TDMA) protocol using the Xilinx FPGA Virtex-5 board. This flexible framework design offers network systems engineers a reconfigiirable platform for triple-play systems development. In this work, MicorBlaze is used to perform memory and connectivity tests aiming to ensure the establishment of the connectivity as well as board’s processor stability. Two different approaches are followed to achieve TP-TDMA implementa­tion: systematic and conceptual. In the systematic approach, a bottom-to-top design is chosen where four subsystems are built with various components. Each component is then tested individually to investigate its response. On the other hand, the concep­tual approach is designed with only two components, in which one of them is created with the help of Xilinx Integrated Software Environment (ISE) Core Generator. The system is integrated and then tested to check its overall response. In summary, the work of this thesis is divided into three sections. The first section presents a testing method for Virtex-5 board using MicroBlaze soft processor. The following two sections concentrate on implementing the TP-TDMA protocol on the board by using two design approaches: one based on designing each component from scratch, while the other one focuses more on the system’s broader picture

    Measurement Design of Sensor Node for Landslide Disaster Early Warning System

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    Landslide is one of the most frequent disaster happened in Indonesia. It can occur due to some major factors, e.g.; high rainfall and soil moisture. In order to predict the occurrence of landslide disaster, data sensing system of these factors are acquired. A prototype of data acquisition is proposed. The prototype provides sensors for sensing of four parameters, which are MPU 6050 sensor, tipping bucket with reed switch, two of FC-28 humidity sensors, and 801s sensor, to measure slope, rainfall, moisture, and ground vibration, respectively. This system is also equipped with the process of data retrieval or log data in real-time with SD Card in the process directly and delivery via the server via SIM900. From the sensor test results, which are obtained from reading value of each sensor, the system shows low error values of 0.165, 0, 0, 0.39, and 0.71, for MPU6050, tipping bucket, 801S, and the two of FC-28 sensors, respectively

    Architecture of the regional satellite augmentation system for maritime applications

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    This paper describes architecture of regional satellite augmentation system (RSAS) in the function of the maritime space communications, navigation and surveillance (CNS) and global navigation satellite systems (GNSS) networks for enhanced safety and surveying of oceangoing ships, management and tracking of cargo, security of Mariners onboard commercial and passenger ships, yachts, sea platforms and other types of craft. The RSAS network are designed to improve vessel management and transport operation because of the enormous expansion of the world's merchant fleet. However, this network with a special ship tracking system can also improve the protection of merchant ships and their crews against piracy, violence, robbery and terrorist attacks. The international maritime organization (IMO) and shipping flag states have project for development of the international ship and port security (ISPS) and design to implement an approaching and port control system (APCS) by special code for all merchant vessels including determination, tracking and positioning of all ships movements in and out of the seaport area. The Maritime RSAS and CNS systems are integration components of the global satellite augmentation systems (GSAS) of two operational GNSS-1 military networks, such as the US global position system (GPS) and Russian global satellite navigation system (GLONASS). In this paper are also introduced the special effects of the ships RSAS networks and coastal movement guidance and control (CMGC) system for maritime application at sea and in seaports areas

    Design of a High Capacity, Scalable, and Green Wireless Communication System Leveraging the Unlicensed Spectrum

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    The stunning demand for mobile wireless data that has been recently growing at an exponential rate requires a several fold increase in spectrum. The use of unlicensed spectrum is thus critically needed to aid the existing licensed spectrum to meet such a huge mobile wireless data traffic growth demand in a cost effective manner. The deployment of Long Term Evolution (LTE) in the unlicensed spectrum (LTE-U) has recently been gaining significant industry momentum. The lower transmit power regulation of the unlicensed spectrum makes LTE deployment in the unlicensed spectrum suitable only for a small cell. A small cell utilizing LTE-L (LTE in licensed spectrum), and LTE-U (LTE in unlicensed spectrum) will therefore significantly reduce the total cost of ownership (TCO) of a small cell, while providing the additional mobile wireless data offload capacity from Macro Cell to small cell in LTE Heterogeneous Networks (HetNet), to meet such an increase in wireless data demand. The U.S. 5 GHz Unlicensed National Information Infrastructure (U-NII) bands that are currently under consideration for LTE deployment in the unlicensed spectrum contain only a limited number of 20 MHZ channels. Thus in a dense multi-operator deployment scenario, one or more LTE-U small cells have to co-exist and share the same 20 MHz unlicensed channel with each other and with the incumbent Wi-Fi. This dissertation presents a proactive small cell interference mitigation strategy for improving the spectral efficiency of LTE networks in the unlicensed spectrum. It describes the scenario and demonstrate via simulation results, that in the absence of an explicit interference mitigation mechanism, there will be a significant degradation in the overall LTE-U system performance for LTE-U co-channel co-existence in countries such as U.S. that do not mandate Listen-Before-Talk (LBT) regulations. An unlicensed spectrum Inter Cell Interference Coordination (usICIC) mechanism is then presented as a time-domain multiplexing technique for interference mitigation for the sharing of an unlicensed channel by multi-operator LTE-U small cells. Through extensive simulation results, it is demonstrated that the proposed usICIC mechanism will result in 40% or more improvement in the overall LTE-U system performance (throughput) leading to increased wireless communication system capacity. The ever increasing demand for mobile wireless data is also resulting in a dramatic expansion of wireless network infrastructure by all service providers resulting in significant escalation in energy consumption by the wireless networks. This not only has an impact on the recurring operational expanse (OPEX) for the service providers, but importantly the resulting increase in greenhouse gas emission is not good for the environment. Energy efficiency has thus become one of the critical tenets in the design and deployment of Green wireless communication systems. Consequently the market trend for next-generation communication systems has been towards miniaturization to meet this stunning ever increasing demand for mobile wireless data, leading towards the need for scalable distributed and parallel processing system architecture that is energy efficient, and high capacity. Reducing cost and size while increasing capacity, ensuring scalability, and achieving energy efficiency requires several design paradigm shifts. This dissertation presents the design for a next generation wireless communication system that employs new energy efficient distributed and parallel processing system architecture to achieve these goals while leveraging the unlicensed spectrum to significantly increase (by a factor of two) the capacity of the wireless communication system. This design not only significantly reduces the upfront CAPEX, but also the recurring OPEX for the service providers to maintain their next generation wireless communication networks

    Intrusion detection system in software-defined networks

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    Mestrado de dupla diplomação com a UTFPR - Universidade TecnolĂłgica Federal do ParanĂĄSoftware-Defined Networking technologies represent a recent cutting-edge paradigm in network management, offering unprecedented flexibility and scalability. As the adoption of SDN continues to grow, so does the urgency of studying methods to enhance its security. It is the critical importance of understanding and fortifying SDN security, given its pivotal role in the modern digital ecosystem. With the ever-evolving threat landscape, research into innovative security measures is essential to ensure the integrity, confidentiality, and availability of network resources in this dynamic and transformative technology, ultimately safeguarding the reliability and functionality of our interconnected world. This research presents a novel approach to enhancing security in Software-Defined Networking through the development of an initial Intrusion Detection System. The IDS offers a scalable solution, facilitating the transmission and storage of network traffic with robust support for failure recovery across multiple nodes. Additionally, an innovative analysis module incorporates artificial intelligence (AI) to predict the nature of network traffic, effectively distinguishing between malicious and benign data. The system integrates a diverse range of technologies and tools, enabling the processing and analysis of network traffic data from PCAP files, thus contributing to the reinforcement of SDN security.As tecnologias de Redes Definidas por Software representam um paradigma recente na gestĂŁo de redes, oferecendo flexibilidade e escalabilidade sem precedentes. À medida que a adoção de soluçÔes SDN continuam a crescer, tambĂ©m aumenta a urgĂȘncia de estudar mĂ©todos para melhorar a sua segurança. É de extrema importĂąncia compreender e fortalecer a segurança das SDN, dado o seu papel fundamental no ecossistema digital moderno. Com o cenĂĄrio de ameaças em constante evolução, a investigação de medidas de segurança inovadoras Ă© essencial para garantir a integridade, a confidencialidade e a disponibilidade dos recursos da rede nesta tecnologia dinĂąmica e transformadora. Esta investigação apresenta uma nova abordagem para melhorar a segurança nas redes definidas por software atravĂ©s do desenvolvimento de um sistema inicial de deteção de intrusĂ”es. O IDS oferece uma solução escalĂĄvel, facilitando a transmissĂŁo e o armazenamento do trĂĄfego de rede com suporte robusto para recuperação de falhas em vĂĄrios nĂłs. AlĂ©m disso, um mĂłdulo de anĂĄlise inovador incorpora inteligĂȘncia artificial (IA) para prever a natureza do trĂĄfego de rede, distinguindo efetivamente entre dados maliciosos e benignos. O sistema integra uma gama diversificada de tecnologias e ferramentas, permitindo o processamento e a anĂĄlise de dados de trĂĄfego de rede a partir de ficheiros PCAP, contribuindo assim para o reforço da segurança SDN

    A survey of temporal knowledge discovery paradigms and methods

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    With the increase in the size of data sets, data mining has recently become an important research topic and is receiving substantial interest from both academia and industry. At the same time, interest in temporal databases has been increasing and a growing number of both prototype and implemented systems are using an enhanced temporal understanding to explain aspects of behavior associated with the implicit time-varying nature of the universe. This paper investigates the confluence of these two areas, surveys the work to date, and explores the issues involved and the outstanding problems in temporal data mining

    Exploring e-learning adoption in nurse education: a socio-cultural case study using Q and Bourdieu

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    This research study employed Q-methodology (Q) to explore the factors influencing e-learning adoption in a nurse education context, and Bourdieu’s Theory of Practice (TOP) to analyse these findings using a case study of one school of nursing in the UK. E-learning adoption has been limited in nurse education despite a wide body of literature promoting its use for improved learning outcomes. Most research studies to date have used surveys to explore the overarching factors influencing academics to adopt e-learning across higher education more generally, but these findings have not identified the underlying issues influencing their responses to these factors, nor do they allow a deep analysis of discipline-specific factors. This study identified four groups (Factors) of academics each responding differently towards e-learning in their teaching. The first group represented the ‘e-advocates’ who saw technology as having the potential to improve nurse education by giving more control to learners and preparing future nurses for their evolving role in health care. The second group represented the ‘humanists’ who although sharing similar pedagogical beliefs as the first group had not been motivated to engage with technology because of the value they placed on human interaction. The third group was described as the ‘sceptics’ who had had previous negative experiences with e-learning and were unconvinced about technology’s ability to improve learning outcomes. Finally, the fourth factor, the ‘pragmatics,’ although ostensibly positive in their views towards e-learning, held different pedagogical beliefs from the three other groups and felt it was their responsibility to cover certain content in a face-to-face setting. The unique combination of Q and Bourdieu’s TOP enabled a deeper analysis of the four groups’ views and the socio-cultural context shaping them, thus providing new insights into academics’ responses to e-learning. Moving beyond the binary labels commonly attributed to those considered either ‘early adopters’ or ‘laggards,’ the findings make a contribution to the e-learning adoption literature by revealing a wider breadth of views and responses towards technology. Moreover, this study showed that internal beliefs determined the extent to which external factors were perceived as influential. This serves to explain why some individuals overcome certain barriers to e-learning adoption whilst others succumb to them. The findings from this study will inform policy-makers, e-learning strategists and professional development staff on how to more effectively present and promote e-learning
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