Editorial

This volume of the Bulletin LIBRARIES and the next intended as a means of inspiration. Inspiration to propose ideas to offer to the community library paths to adapt to global culture and technology which revolves around the progress of information and communication systems. Ideas that move us to innovate, to make mistakes and correct them.Because the information age it is also of creativity. Creativity is the competitive advantage of professional and modern organizations. Ideas to change attitudes toward open to new projects that facilitate the transformation and to the challenge of "going global". Inspiration to measure and produce constructive thinking to help us define new goals by the desire to create and share knowledge.

A test method for analysing disturbed ethernet data streams

Ethernet connections, which are widely used in many computer networks, can suffer from electromagnetic interference. Typically, a degradation of the data transmission rate can be perceived as electromagnetic disturbances lead to corruption of data frames on the network media. In this paper a software-based measuring method is presented, which allows a direct assessment of the effects on the link layer. The results can directly be linked to the physical interaction without the influence of software related effects on higher protocol layers. This gives a simple tool for a quantitative analysis of the disturbance of an Ethernet connection based on time domain data. An example is shown, how the data can be used for further investigation of mechanisms and detection of intentional electromagnetic attacks. © 2015 Author(s).

Motion compensation with minimal residue dispersion matching criteria

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnoloigia, 2016.

Propuesta de un marco de referencia simplificado para la implementación de un Gobierno de TI en Pymes de Servicios en Colombia

El siguiente trabajo de grado propone un modelo simplificado de gobierno y gestión de las tecnologías de información en las pequeñas y medianas empresas de servicios en Colombia, a partir de la selección e integración de procesos enunciados por algunos de los marcos de trabajo y buenas prácticas de TI que gozan de un reconocimiento generalizado -- En concreto, se han tomado elementos de COBIT 5, ISO/IEC 20000, ITIL V3, CMMI 1.3, PMBOK 5 e ISO/IEC 27000 -- Para el diseño del modelo propuesto se han identificado cada uno de los procesos dispuestos por los diferentes marcos de referencia -- Acto seguido se ha procedido a identificar todos los procesos comunes entre los diferentes modelos de gestión, seleccionando aquellos que se consideran imprescindibles en la generación de valor y evitando aquellos que complejizaran la gestión para el foco de nuestro alcance -- Los procesos identificados y seleccionados fueron agrupados bajo áreas de proceso, las cuales, a su vez, describen subprocesos que tienen un propósito declarado y unas estrategias de gestión y actividades propuestas, que seguidas, satisfacen el objetivo establecido para cada uno de los subprocesos, y en conjunto, suponen un modelo de gobierno de TI adecuado para las pequeñas y medianas empresas prestadoras de servicios en Colombia

Testing the level of interactivity of institutional websites: From museums 1.0 to museums 2.0

The Internet has changed the way in which organizations communicate with their publics, and museums are not an exception. The consolidation of Web 2.0 has not only given museums access to a powerful new tool for disseminating information, but has involved significant changes in the relationship between institutions and their publics, facilitating and enhancing the interaction between them. The overall objective of this paper is to analyze the degree of interactivity implemented in the websites of major international art museums, in order to assess if museums are evolving towards more dialogic systems with relation to their publics. The results indicate that museums still have a low level of interactivity on their websites, both in the tools used to present information and the resources available for interaction with virtual visitors. But it has also observed that museums are progressively implementing interactive and dialogic sources, suggesting a clear trend towards new ways of managing these platforms in order to establish more participatory and collaborative communication systems with virtual users.

Un modelo de indicadores de gestión de comunicación organizacional para la Universidad de Antioquia: un aporte a la gestión estratégica de la comunicación en instituciones universitarias

El presente trabajo tiene como propósito formular un sistema de indicadores de comunicación que se constituya en un instrumento valioso para el ejercicio de planeación, seguimiento y evaluación de la gestión comunicativa al interior de la Universidad de Antioquia -- Además de la mejora continua del proceso de comunicación institucional y una toma de decisiones más efectiva, se espera que la implementación del sistema de indicadores permita un posicionamiento estratégico del área de comunicaciones en articulación con sus diferentes dependencias, al valorar con mayor claridad su contribución al logro de los objetivos estratégicos planteados por la Alma Máter -- Para el logro de dicho objetivo trazaron tres etapas -- La primera comprende un estado del arte en el que se incluyen los aportes teóricos sobre la medición y la evaluación de la comunicación en las organizaciones, la información de contexto requerida sobre la institución objeto de estudio y un diagnóstico sobre el estado de la comunicación en la misma, basado en estudios elaborados previamente por la institución -- La segunda etapa corresponde al trabajo de campo, que parte de una combinación de técnicas investigativas cuantitativas (encuesta) y cualitativas (grupo focal) -- Con el análisis de la información obtenida en tales fases, al final se formula una propuesta de indicadores de cumplimiento, satisfacción e impacto para cada uno de los asuntos de trabajo del proceso de comunicación institucional proyectado en la actualidad por la Universidad de Antioquia

Solution to reduce nonlinearity in LTE RoF system for an efficient das topology:a brief review

In this paper, a review on radio-over-fiber (RoF) technology is conducted to support the exploding growth of mobile broadband. An RoF system will provide a platform for distributed antenna system (DAS) as a fronthaul of long term evolution (LTE) technology. A higher splitting ratio from a macrocell is required to support large DAS topology, hence higher optical launch power (OLP) is the right approach. However, high OLP generates undesired nonlinearities, namely the stimulated Brillouin scattering (SBS). Three different aspects of solving the SBS process are covered in this paper, where the solutions ultimately provided an additional 4 dB link budget.

Real-time PMU monitoring of an IEEE 5-Bus Network implemented on OPAL system

This thesis studies the state-of-the-art of phasor measurement units (PMUs) as well as their metrological requirements stated in the IEEE C37.118.1 and C37.118.2 Standards for guaranteeing correct measurement performances. Communication systems among PMUs and their possible applicability in the field of power quality (PQ) assessment are also investigated. This preliminary study is followed by an analysis of the working principle of real-time (RT) simulators and the importance of hardware-in-the-loop (HIL) implementation, examining the possible case studies specific for PMUs, including compliance tests which are one of the most important parts. The core of the thesis is focused on the implementation of a PMU model in the IEEE 5-bus network in Simulink and in the validation of the results using OPAL RT-4510 as a real-time simulator. An initial check allows one to get an idea about the goodness of the results in Simulink, comparing the PMU data with respect to the load-flow steady-state information. In this part, accuracy indices are also calculated for both voltage and current synchrophasors. The following part consists in the implementation of the same code in OPAL-RT 4510 simulator, after which an initial analysis is carried out in a qualitative way in order to get a sense of the goodness of the outcomes. Finally, the confirmation of the results is based on an examination of the attained voltage and current synchrophasors and accuracy indices coming from Simulink models and from OPAL system, using a Matlab script. This work also proposes suggestions for an upcoming operation of PMUs in a more complex system as the Digital Twin (DT) in order to improve the performances of the already-existing protection devices of the distribution system operator (DSO) for a future enhancement of power systems reliability.

Efficient wireless coverage of in-building environments with low electromagnetic impact

The city of tomorrow is a major integrating stake, which crosses a set of major broad spectrum domains. One of these areas is the instrumentation of this city and the ubiquity of the exchange of data, which will give the pulse of this city (sensors) and its breathing in a hyper-connected world within indoor and outdoor dense areas (data exchange, 5G and 6G). Within this context, the proposed doctorate project has the objective to realize cost- and energy- effective, short-range communication systems for the capillary wireless coverage of in-door environments with low electromagnetic impact and for highly dense outdoor networks. The result will be reached through the combined use of: 1) Radio over Fiber (RoF) Technology, to bring the Radio Frequency (RF) signal to the different areas to be covered. 2) Beamforming antennas to send in real time the RF power just in the direction(s) where it is really necessary.

Televisioni in transito: modelli produttivi e immaginari urbani di mobilita

Il termine go-tv fa riferimento a i sistemi di videocomunicazione collocati a bordo di mezzi di trasporto e in ambienti collegati, ad alto transito di passeggeri. Limitando l’analisi al territorio italiano, la ricerca intende ricostruire le coordinate storiche del suo sviluppo, inquadrandolo entro il più ampio contesto dei media contemporanei. Da un punto di vista teorico, sono considerati sia il legame del mezzo con l’ambiente urbano, sia le interconnessioni tra comunicazione, mobilità e trasporti, riflesse nel particolare statuto sociale e topologico chiamato in causa dai suoi luoghi di consumo. Dall’approvvigionamento alla messa in onda dei contenuti, cardine speculativo del lavoro è la disamina, su base esplorativa, delle consuetudini commerciali e professionali sottese a questo speciale canale di distribuzione audiovisiva, nel quadro di apposite pratiche d’azienda, campionate nel solco degli studi sulla produzione mediale. Tre sono gli snodi principali del progetto: la proposta di una definizione univoca del fenomeno, condivisibile dai diversi attori coinvolti nella filiera, una prima modellizzazione del suo profilo mediale e una mappatura dei principali casi di go-tv rinvenibili a livello nazionale, arricchita da una serie di studi di caso.

NB-IoT via non terrestrial networks

Massive Internet of Things is expected to play a crucial role in Beyond 5G (B5G) wireless communication systems, offering seamless connectivity among heterogeneous devices without human intervention. However, the exponential proliferation of smart devices and IoT networks, relying solely on terrestrial networks, may not fully meet the demanding IoT requirements in terms of bandwidth and connectivity, especially in areas where terrestrial infrastructures are not economically viable. To unleash the full potential of 5G and B5G networks and enable seamless connectivity everywhere, the 3GPP envisions the integration of Non-Terrestrial Networks (NTNs) into the terrestrial ones starting from Release 17. However, this integration process requires modifications to the 5G standard to ensure reliable communications despite typical satellite channel impairments. In this framework, this thesis aims at proposing techniques at the Physical and Medium Access Control layers that require minimal adaptations in the current NB-IoT standard via NTN. Thus, firstly the satellite impairments are evaluated and, then, a detailed link budget analysis is provided. Following, analyses at the link and the system levels are conducted. In the former case, a novel algorithm leveraging time-frequency analysis is proposed to detect orthogonal preambles and estimate the signals’ arrival time. Besides, the effects of collisions on the detection probability and Bit Error Rate are investigated and Non-Orthogonal Multiple Access approaches are proposed in the random access and data phases. The system analysis evaluates the performance of random access in case of congestion. Various access parameters are tested in different satellite scenarios, and the performance is measured in terms of access probability and time required to complete the procedure. Finally, a heuristic algorithm is proposed to jointly design the access and data phases, determining the number of satellite passages, the Random Access Periodicity, and the number of uplink repetitions that maximize the system's spectral efficiency.

Radiation characteristics enhancement of planar structures using metasurfaces

In this thesis, the focus is on utilizing metasurfaces to improve radiation characteristics of planar structures. The study encompasses various aspects of metasurface applications, including enhancing antenna radiation characteristics and manipulating electromagnetic (EM) waves, such as polarization conversion and anomalous reflection. The thesis introduces the design of a single-port antenna with dual-mode operation, integrating metasurfaces. This antenna serves as the front-end for a next-generation tag, functioning as a position sensor with identification and energy harvesting capabilities. It operates in the lower European Ultra-Wideband (UWB) frequency range for communication/localization and the UHF band for wireless energy reception. The design aims for a low-profile stack-up that remains unaffected by background materials. Researchers worldwide are drawn to metasurfaces due to their EM wave manipulation capabilities. The thesis also demonstrates how a High-Impedance Surface (HIS) can enhance the antenna's versatility through metasurface application, including conformal design using 3D-printing technology, ensuring adaptability for various deformation and tracking/powering scenarios. Additionally, the thesis explores two distinct metasurface applications. One involves designing an angularly stable super-wideband Circular Polarization Converter (CPC) operating from 11 to 35GHz with an impressive relative impedance bandwidth of 104.3%. The CPC shows a stable response even at oblique incidences up to 40 degrees, with a Peak Cross-Polarization Ratio (PCR) exceeding 62% across the entire band. The second application focuses on an Intelligent Reflective Surface (IRS) capable of redirecting incoming waves in unconventional directions. Tunability is achieved through an artificially developed ferroelectric material (HfZrO) and distributed capacitive elements (IDC) to fine-tune impedance and phase responses at the meta-atom level. The IRS demonstrates anomalous reflection for normal incident waves. These innovative applications of metasurfaces offer promising advancements in antenna design, EM wave manipulation, and versatile wireless communication systems.

Performance Analysis of Topological Quantum Error Correcting Codes

In the last few years there has been a great development of techniques like quantum computers and quantum communication systems, due to their huge potentialities and the growing number of applications. However, physical qubits experience a lot of nonidealities, like measurement errors and decoherence, that generate failures in the quantum computation. This work shows how it is possible to exploit concepts from classical information in order to realize quantum error-correcting codes, adding some redundancy qubits. In particular, the threshold theorem states that it is possible to lower the percentage of failures in the decoding at will, if the physical error rate is below a given accuracy threshold. The focus will be on codes belonging to the family of the topological codes, like toric, planar and XZZX surface codes. Firstly, they will be compared from a theoretical point of view, in order to show their advantages and disadvantages. The algorithms behind the minimum perfect matching decoder, the most popular for such codes, will be presented. The last section will be dedicated to the analysis of the performances of these topological codes with different error channel models, showing interesting results. In particular, while the error correction capability of surface codes decreases in presence of biased errors, XZZX codes own some intrinsic symmetries that allow them to improve their performances if one kind of error occurs more frequently than the others.

Analysis on the implementation of V2X communications for PTWs

Inter-vehicular communications have been gaining momentum throughout the last years and they now occupy a prominent position among the objectives of car manufacturers. Motorcycle manufacturers want to keep pace with the 4 wheels world in order to make Powered Two-wheelers (PTW) integral part of the future connected mobility. The requirements for implementing inter-vehicular communication systems for motorcycles are the subjects of discussion in this thesis. The first purpose of this thesis is to introduce the reader to the world of vehicle-to-everything (V2X) communications, focusing on the Cooperative Intelligent Transport Systems (C-ITS) and the two main current technologies: ITS-G5, which is based on IEEE 802.11p, and cellular vehicle-to-everything (C-V2X). The evolution of these technologies will be also treated. Afterwards, the core of this work is presented: the analysis of the system architecture, including hardware, security, HMI, and peculiar challenges, for implementing V2X systems in motorcycles.