9 research outputs found

    Energy-efficient wireless communication schemes and real-time middleware for machine-to-machine networks

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    Esta tesis estudia sistemas Machine-to-Machine (M2M) en los que se ejecutan tareas de manera autónoma sin, o con mínima intervención humana. Los sistemas M2M están formados por dispositivos desplegados en un entorno que recolectan información relacionada con una tarea y la envían a aplicaciones para su proceso. Las aplicaciones optimizan estas tareas y responden a los dispositivos con comandos de control. Idealmente, después de configurar las políticas de tareas, los humanos son excluidos del lazo de control. Un importante caso de uso en M2M es la automatización de la red eléctrica, también conocido como Smart Grid, que se trata en esta tesis. Muchos escenarios M2M requieren dispositivos de bajo bitrate, bajo coste y que puedan ser fácilmente desplegables y mantenidos. Una solución adecuada son los dispositivos inalámbricos, alimentados por batería y de capacidades limitadas (con reducida potencia de procesado y memoria). Un bajo mantenimiento requiere años de vida, que sólo pueden conseguirse con protocolos de comunicación altamente eficientes energéticamente. En esta tesis nos centramos principalmente en las capas MAC y de enlace (especialmente en esquemas Cooperative Automatic Repeat Request) para mejorar la eficiencia energética de los dispositivos. Proponemos y evaluamos extensiones de Cooperative MAC para varios estándares como IEEE 802.11, IEEE 802.15.4 y sus revisiones MAC. El transmisor radio de los dispositivos puede ponerse en estado de reposo cuando está inactivo, llevando a cortos periodos de activación (duty-cycle) en dispositivos de bajo bitrate, consiguiendo así un ahorro energético considerable. Dado que la capa MAC controla los estados de reposo de los transmisores radio, los esquemas de Duty-Cycle MAC son el pilar de las comunicaciones energéticamente eficientes. Por ello, en esta tesis diseñamos, analizamos y evaluamos esquemas Cooperative and Duty-Cycled ARQ (CDC-ARQ). CDC-ARQ se basa en la (re)transmisión dinámica de paquetes (dynamic packet forwarding) dependiendo del estado del canal inalámbrico. Cuantificamos las ganancias considerando enlaces inalámbricos de baja potencia con modelos realistas, que sufren efectos de apantallamiento (shadowing) desvanecimientos (fading) de canal, y presentamos las condiciones bajo las cuales CDC-ARQ consiguen mejores resultados que las técnicas estándar de forwarding. Finalmente, determinamos estrategias óptimas de selección de enlace y retransmisión para direct, multi-hop y CDC-ARQ forwarding. Los esquemas de comunicación inalámbricos energéticamente eficientes son adecuados, por ejemplo, para automatización de edificios y hogar, contribuyendo a un buen uso de la energía eléctrica en dichos escenarios. Después de considerar el entorno de dispositivos, la tesis se centra en las aplicaciones, al otro lado de los sistemas M2M. Las aplicaciones típicamente intercambian datos sobre amplias zonas con varios dispositivos remotos. Las técnicas de computación distribuida, estandarizadas e implementadas en plataformas middleware para sistemas M2M, facilitan este intercambio de datos. Los requisitos de comunicación de estas aplicaciones son diversos en términos de latencia, número de actualizaciones, número de dispositivos asociados, etc. Mientras que las soluciones middleware existentes tales como ETSI M2M satisfacen los requisitos de ciertas aplicaciones, dichas soluciones son inadecuadas para los requisitos de latencia de transmisión en tiempo real. Esta tesis propone y analiza modificaciones del ETSI M2M que mejoran el rendimiento en tiempo real. El análisis se ejemplifica con tres aplicaciones Smart Grid, una relacionada con la automatización del hogar y edificios, y las otras dos con la monitorización y control del flujo de potencia de la red eléctrica.This thesis studies emerging Machine-to-Machine (M2M) systems that execute automated tasks without, or with minimum human intervention. M2M systems consist of devices deployed in the field to collect task-related information and send it to remote applications for processing. The applications optimise the tasks and issue control commands back to the devices. Ideally, after configuring the task policies, humans are excluded from the control loop. A prominent and urgent M2M use case concentrates on the automation of the electric power grid, also known as Smart Grid, that is considered in the thesis. Many M2M scenarios require devices that are low-rate, low-cost and can be easily deployed and maintained. A fitting solution are wireless, battery-powered and resource-constrained devices (with limited processing power and memory). Low-maintenance requires years of lifetime, that can only be achieved with unprecedented energy efficiency of communication protocols. Specifically, we focus on the MAC and link layers in this thesis (especially on the Cooperative Automatic Repeat Request schemes) to improve the energy efficiency of the devices. Cooperative MAC extensions to the various standard technologies such as IEEE 802.11, IEEE 802.15.4 and its MAC amendments are proposed and evaluated. The radio transceiver of a device can be put to sleep state when inactive, yielding very low duty-cycles for low-rate devices, and thus achieving significant energy savings. Since the MAC layer controls the radio transceiver sleep states, duty-cycled MAC schemes are the cornerstone of the energy-efficient communication schemes. To that end, Cooperative and Duty-Cycled ARQ (CDC-ARQ) scheme has been designed, analysed and evaluated in this thesis. CDC-ARQ is based on dynamic packet forwarding depending on the current state of the wireless channel. The benefits are quantified by considering realistic wireless low-power links that experience shadowing and multipath fading channel effects. The conditions under which CDC-ARQ outperforms the standard forwarding techniques are presented. Finally, optimal link selection and retransmission strategies are determined for direct, multi-hop or CDC-ARQ forwarding. The studied energy-efficient wireless schemes are suitable e.g. for home and building automation which can contribute to the efficient use of the electric power in homes and buildings. After considering the device domain, the focus of this thesis turns to the applications at the other end of the M2M system. The applications typically exchange data over wide areas with many remote devices. Distributed computing techniques facilitate this data exchange, standardised and implemented in the middleware platform for M2M systems. The communication requirements of these applications are diverse in terms of data latency, update rate, number of associated devices etc. While the existing middleware solutions such as ETSI M2M fully support communication requirements of some applications, the solution is inadequate when it comes to the real-time latency constraint. Some suitable upgrades that improve the real-time performance of data exchange in ETSI M2M middleware are analysed in the thesis. The analysis is exemplified with three Smart Grid applications, one related to the home and building automation and the other two concerned with monitoring and control of the power flow in the electric grid

    Wireless Techniques for Body-Centric Cooperative Communications

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    Body-centric and cooperative communications are new trends in telecommunications field. Being concerned with human behaviour, body-centric communication networks, also known as Wireless Body Area Networks (WBANs), are suitable for a wide variety of applications. The advances in the miniaturisation of embedded devices to be placed on or around the body, foster the diffusion of these systems, where the human body is the key element defining communication characteristics. Cooperative communications paradigm, on the other hand, is one of the emerging technologies that promises significantly higher reliability and spectral efficiency in wireless networks. This thesis investigates possible applications of the cooperative communication paradigm to body-centric networks and, more generally, to Wireless Sensor Networks (WSNs). Firstly, communication protocols for WBANs are in the spotlight. Performance achieved by different approaches is evaluated and compared through experimentation providing guidelines for choosing appropriate protocol and setting protocol parameters to meet application requirements. Secondly, a cooperative Multiple Input Multiple Output (MIMO) scheme for WBANs is presented. The scheme, named B-MIMO, exploits the natural heterogeneity of the WBAN propagation channel to improve energy efficiency of the system. Finally, a WSN scenario is considered, where sensor nodes cooperate to establish a massive MIMO-like system. The analysis and subsequent optimisation show the advantages of cooperation in terms of energy efficiency and provide insights on how many nodes should be deployed in such a scenario

    Large space structures and systems in the space station era: A bibliography with indexes

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    Bibliographies and abstracts are listed for 1372 reports, articles, and other documents introduced into the NASA scientific and technical information system between January 1, 1990 and June 30, 1990. Its purpose is to provide helpful information to the researcher, manager, and designer in technology development and mission design according to system, interactive analysis and design, structural and thermal analysis and design, structural concepts and control systems, electronics, advanced materials, assembly concepts, propulsion, and solar power satellite systems

    Abstracts on Radio Direction Finding (1899 - 1995)

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    The files on this record represent the various databases that originally composed the CD-ROM issue of "Abstracts on Radio Direction Finding" database, which is now part of the Dudley Knox Library's Abstracts and Selected Full Text Documents on Radio Direction Finding (1899 - 1995) Collection. (See Calhoun record https://calhoun.nps.edu/handle/10945/57364 for further information on this collection and the bibliography). Due to issues of technological obsolescence preventing current and future audiences from accessing the bibliography, DKL exported and converted into the three files on this record the various databases contained in the CD-ROM. The contents of these files are: 1) RDFA_CompleteBibliography_xls.zip [RDFA_CompleteBibliography.xls: Metadata for the complete bibliography, in Excel 97-2003 Workbook format; RDFA_Glossary.xls: Glossary of terms, in Excel 97-2003 Workbookformat; RDFA_Biographies.xls: Biographies of leading figures, in Excel 97-2003 Workbook format]; 2) RDFA_CompleteBibliography_csv.zip [RDFA_CompleteBibliography.TXT: Metadata for the complete bibliography, in CSV format; RDFA_Glossary.TXT: Glossary of terms, in CSV format; RDFA_Biographies.TXT: Biographies of leading figures, in CSV format]; 3) RDFA_CompleteBibliography.pdf: A human readable display of the bibliographic data, as a means of double-checking any possible deviations due to conversion

    BEYOND ALL LIMITS : Procedings on International Conference on Sustainability in Architecture, Planning, and Design : 11-12, 13 May 2022

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    [Italiano]: Il volume raccoglie gli atti della seconda edizione del convegno “BEYOND ALL LIMITS. International Conference on Sustainability in Architecture, Planning, and Design”, tenutosi nei giorni 11 e 12 maggio 2022, presso il Complesso del Belvedere di San Leucio, sede di Officina Vanvitelli. Il convegno è stato promosso e organizzato dal Dipartimento di Architettura e Disegno Industriale dell'Università degli Studi della Campania “Luigi Vanvitelli”, in partnership con la Faculty of Architecture della Çankaya University di Ankara e la Faculty of Engineering della University of Strathclyde di Glasgow. L’obiettivo principale di questo convegno scientifico e multidisciplinare, che ha interessato i campi dell'architettura, della pianificazione e del design, è stato quello di affrontare il tema della sostenibilità all’interno dell'attuale dibattito internazionale scaturito dal New European Bauhaus (NEB)./[English]: This volume collects the Proceedings of the second edition of the conference “BEYOND ALL LIMITS. International Conference on Sustainability in Architecture, Planning, and Design”, held on May 11 and 12, 2022, at the San Leucio Belvedere Complex, home of Officina Vanvitelli. The conference was sponsored and organized by the Department of Architecture and Industrial Design of the University of Campania “Luigi Vanvitelli”, in partnership with the Faculty of Architecture of Çankaya University in Ankara and the Faculty of Engineering of the University of Strathclyde in Glasgow. The main objective of this scientific and multidisciplinary conference, which covered the fields of architecture, planning and design, was to address the issue of sustainability within the current international debate that has arisen from the New European Bauhaus (NEB)

    Empowering vulnerable women by participatory design workshops

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    This contribution addresses the issue of homeless women’s empowerment through design workshops and according to the capability approach. The paper presents small, ordinary stories of women that experience being designers. Besides the professional label, being a designer means to approach reality from the transformative perspective of pursuing a positive change. It also translates in claiming the space for the expression of a personal vision of the world, within a cooperative environment. It enables to experiment innovative strategies to solve problems and to pursue self-determination in practical activities

    Trial efficacy vs real world effectiveness in first line treatment of multiple myeloma

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    Background: Large randomized clinical trials (RCT) are the foundation of the registration of newly developed drugs. A potential problem with RCTs is that the inclusion/exclusion criteria will make the population different from the actual population treated in real life. Hence, it is important to understand how the results from the RCT can be generalized to a general population. Aims: The primary aim of the present study was to assess the generalizability of the large 1st line RCTs in Multiple Myeloma (MM) to the Nordic setting and to understand potential difference and magnitude in outcomes between RCTs and patients treated in standard care in the Nordics. Methods: A retrospective analysis was performed on an incident cohort of 2960 MM-patients from 24 hospitals in Denmark, Finland, Norway and Sweden. The database contained information on patient baseline characteristics, treatments and outcomes. Data from relevant 1st line MM RCTs was selected from the treatment MP (Waage, A., et al., Blood. 2010], MPT (Waage, A., et al., Blood. 2010) and VMP (San Miguel, J.F., et al., N Engl J Med, 2008) and baseline characteristics were compared to newly diagnosed Nordic MM treated patients. Potential difference in response and overall survival (OS) was estimated by adjusting the RWE population to the RCT population using matching adjusted indirect comparisons. Patients were matched on age (median approximated to mean), gender, calcium, beta2-microglobulin and ISS score 3. These variables were selected because they were reported in all trials and have previously been identified as having prognostic value. Results: Patients in the Nordic database treated with MP (n=880) had a response rate of (PD, NR, PR, VGPR, ≥nCR) of (13%, 39%, 38%, 6%, 4%). After matching (n=347), the response rate was slightly worse (12%, 43%, 36%, 6%, 3%). This can be compared to the response rate from the RCT of (7%, 53%, 33%, 3%, 4%). OS for Nordic MP treated patients was 2.67 years (2.25-3.17). After matching the OS was 3.37 years (2.86-3.96) and this can be compared to the trial with OS 2.40 years (2.23-2.66). Patients treated with MPT (n=283) in the Nordic countries had a response rate of (5%, 14%, 52%, 20%, 9%). After matching (n=179) the response rate was slightly changed to (6%, 20%, 50%, 13% 11%). The corresponding RCT response results were 14%, 29%, 34%, 10%, and 13% respectively. OS for Nordic MPT treated patients was 4.15 years (3.73- 4.74). After matching the OS was 4.28 years (3.98-NA) years and compared to 2.42 years (2.08-3.17) OS observed in the corresponding trial. Patients treated with VMP (n=59) in the Nordic countries had a response rate of (4%, 5%, 40%, 18%, 33%). After matching (n=31) the response rate was improved to (8%, 11%, 28%, 8%, 45%). This corresponding response rates shown in the trial are 1%, 23%, 33%, 8%, and 33% respectively. OS for Nordic MP treated patients was 4.86 years (3.79-NA). After matching the OS was 4.86 years (4.86-NA) and this can be compared to the trial with OS 4.70 years. Summary and Conclusions: Surprisingly Nordic treated MM patients do very well compared to, and even better than, patients treated in RCTs. Since the OS for all tested treatments improves after matching to the RCT baseline characteristics, patients recruited to the RCTs seems to be a bit better than ordinary Nordic patents. The database used in the present study, and the used method, can be valuable for generalizing the results to the Nordic setting and estimating potential difference for future RCTs and Nordic MM treated patients. Future research should include different data cuts to see whether the analyses are biased by differences subsequent treatments applied in RCTs and clinical practice

    Micro-costing study of rituximab subcutaneous injection versus intravenous infusion in dutch setting

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    Background: Rituximab for subcutaneous (SC) administration has recently been approved for use in common forms of diffuse large B-cell lymphoma (DLBCL). This form of rituximab is supplied in ready-to-use vials that do not require individual dose adjustment. It is expected that SC-injection will shorten the treatment time per administration of rituximab in comparison with currently available intravenous (IV) infusion. Aims: The goal of this study is to identify and compare all direct costs of IV and SC rituximab given to the DLBCL patients in the Netherlands. Methods: Using a prospective, observational, bottom up, micro-costing study we collected primary data on the direct medical costs of the preparation, administration and acquisition of rituximab. Drug costs and spillage, labor costs, material costs and remaining daycare costs were identified using standardized forms, structured using guideline prices and compared for the IV and SC forms of rituximab. Results: Measurements were done on 53 administrations (33 IV and 20 SC). The mean total costs of the IV infusion were €2174, and €1907 for the SC injection. The estimated difference of €267 per administration was mainly due to spillage costs and differences in chair time, related daycare costs and drug costs. Summary and Conclusions: Rituximab administered in the form of SC injection is less costly than its IV form. Taking into account their equal effectiveness, favorable pharmacoeconomic profile of SC rituximab can result in significant savings when transferred to the total DLBCL population in the Netherlands
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