Web-Based Toolkit for Performance Simulation and Analysis of Power Line Communication Networks

AMIs (Advanced Metering Infrastructures) present an important role in Smart City environments, especially from the point of view of distribution and customers, offering control and monitoring capabilities. The use of PLC (Power Line Communication) technology offers a wide range of advantages in AMI, including not needing to deploy an additional communication infrastructure. However, the electrical network was not initially designed for communications, as these networks pose problems depending on the connected loads, such as network impedance variation, frequency selectivity or noise. For this reason, the use of simulators is proposed to facilitate the deployments based on PLC networks, and analysis and diagnosis tools for the identification of problems in operating networks are also required. This paper presents a toolkit for evaluating and analyzing the performance of PLC networks. This toolkit is composed of SimPRIME, a simulator for the evaluation of NB-PLC PRIME (PoweR line Intelligent Metering Evolution) networks’ performance; SimBPL, a simulator for the evaluation of MV-BPL (Broadband Power Line over Medium Voltage) cells’ performance; and PRIME Analytics, a forensics tool that allows diagnosis of communication problems in PRIME operational networks based on traffic traces. The toolkit has been developed throughout several research projects in close collaboration with DSOs (Distribution System Operators) and equipment manufacturers, so they provide solutions to actual problems of these industry key players and have been adapted to facilitate their use. As a result, the tools are accessible through web applications to increase their usability, portability, and scalability. These applications represent the first steps in offering PLC simulation and analysis as a service that could benefit the research community, academia, and industry.

Illuminating the blind spot of sub-mesoscale phenomena with a dense station network

<p>Between June and August 2020 an observational network of 103 autonomous ground-based stations covered the greater area (50 km × 35 km) of Hamburg (Germany) within the framework of the FESST@HH field experiment. The purpose of the experiment was to conduct meteorological measurements at sub-mesoscale resolution (500 m to 5 km) to observe phenomena that typically remain unresolved in operational networks. The experimental design focuses on studying cold pools that form through evaporation underneath precipitating clouds and spread on the Earth’s surface.</p><p>During the experiment 82 low-cost APOLLO (Autonomous cold POoL LOgger) stations sampled air temperature and pressure at 1 s resolution to adequately capture the rapid signals of horizontally propagating cold-pool fronts. A secondary network of 21 autonomous weather stations with commercial sensors provided additional information on relative humidity, wind speed and precipitation at 10 s resolution. This work introduces the novel type of instruments, describes the generated data set, and presents first results of the experiment.</p><p>Over the three-month period the FESST@HH network experienced more than 30 cold-pool events of different strength and size. Case studies demonstrate that the observations allow to capture the internal structure and growth of a cold pool and to infer its vertical depth based on the hydrostatic assumption. The data set does not only provide novel insights into the life cycle of cold pools, but also opens new perspectives on phenomena like the urban heat island. Moreover, the experiment may serve as a prototype for the design of future observational networks, including citizen science approaches.</p>

Architecture for integrating vertical customer’s programmability control of network functions and connectivity in a slice-as-a-service schema

Network slicing will permit offering to vertical customers tailored end-to-end logical networks in an on-demand fashion, on top of a common telecom infrastructure, achieving a Slices-as-a-Service (SlaaS) business model. This is possible due to the progressive introduction of network softwarization techniques, such as programmability and virtualization, into existing operational networks, enabling dynamic and flexible provision of slices. Those vertical customers could require the control not only of the network functions composing the end-to-end service, but also of the connectivity among them, e.g., for influencing the paths for steering traffic among function instances. However, this can be problematic since decisions from one vertical customer can collide with decisions from others. One aspect not yet sufficiently investigated is how to permit vertical customers to jointly control the service functions and the underlay connectivity, in such a way that could operate the allocated slice as if it was actually a dedicated network entirely for them. This paper explores some architectural proposition in this respect illustrated with some potential use cases and it provides an example of the provision of SlaaS for a vertical customer.

Sub-mesoscale cold-pool observations during FESST@HH 2020

<p>Cold pools are areas of cool downdraft air, that form through evaporation underneath precipitating clouds and spread on the surface as density currents. Their importance for the development and maintenance of convection is long known. Modern Large-Eddy simulations with a grid spacing of 1 km or less explicitly resolve cold pools, however, they lack reference data for an adequate validation. Available operational networks are too coarse and, therefore, miss the horizontal structure and dynamics of cold pools.</p><p>The pioneering field experiment FESST@HH aims to shed light on this observational blind spot. During summer 2020 a dense network of 102 ground-based stations covering the greater area of Hamburg (Germany) realized meteorological measurements at sub-mesoscale resolution (Δx < 2 km, Δt ≤ 10 s), that provide novel insights into previously unobserved features of cold pools. Over three months more than 30 cold-pool events of different strength and size from various types of convection were detected. Analyses of prominent cases suggest a strong relationship between the local perturbations in air temperature and pressure within a cold pool, that allows inference about its vertical depth based on the hydrostatic assumption. Furthermore, temporary decoupling of horizontal variability in these signals reveal the presence of local non-hydrostatic pressure perturbations caused by convective downdrafts. The presented work will help to better understand the characteristics and life cycle of cold pools and to identify potential biases in convection-permitting simulations.</p>

Migration and the geopolitics of Boko Haram terrorism in Nigeria

Terrorism is increasingly becoming a major threat to global peace and security given the changing geopolitical terrain on which it is enacted. This has given rise to new metageographies of geopolitics characterised by intricate operational networks used by terrorists to achieve their goals. Closely linked to the growing problem of terrorism is globalisation, which has altered our understanding of the geopolitical behaviour of states in the international system. Although it has not removed state boundaries, globalisation has also opened states up for flows and exchanges. Terrorist groups are part of these flows and they have been able to exploit this new geopolitical situation through the recruitment of migrants and the development of terrorist networks across state boundaries. Boko Haram in Nigeria is a typical example of a terrorist group that has evolved into a sophisticated terrorist sect with illegal migrant recruits and transnational networks through the changing geopolitics brought on by globalisation. This article therefore explores the metageography of Boko Haram in Nigeria and how this is aided by migration and social networking occasioned by globalisation. It does so by examining the various structures of the sect, and the nature of its networks. By using the mutual or collective interest theory, the article attempts an explanation of how Boko Haram operates as a group with linkages to diverse transnational terrorist groups bound by a common group interest; anti-Westernisation and global Islamisation. It concludes that Boko Haram has developed a decentralised but sophisticated transnational network which makes it even more difficult for the Nigerian government to deal with its spread.

Avaliação do Processo para Embarcar uma Rede Neural Baseada em YOLO Utilizando um Acelerador de Hardware Dedicado

Object Detection is a challenging task in computer vision, but Deep Neural Networks (DNN) have made great progress in this area. This work presents the process and the results obtained in the attempts to embed a YOLO V3 model in a Neural Compute Engine, the Movidius Stick. Experiments were carried out with a Tensorflow model that is converted to Movidius (using OpenVINO) including an evaluation of the Movidius stick connected to a Raspberry Pi3. The application uses aerial images of power distribution towers captured by a drone. Although there are some fully operational networks for Neural Compute Engines, there are some difficulties in porting new networks to the platform, with gains in performance, but with losses in accuracy.

Sub-mesoscale observations of cold pools during FESSTVaL

<p>Cold pools are areas of cool downdraft air that form through evaporation underneath precipitating clouds and spread on the surface as density currents. Their importance for the development and maintenance of convection is long known. Modern Large-Eddy simulations with a grid spacing of 1 km or less are able to explicitly resolve cold pools, however, they lack reference data for an adequate validation. Available point measurements from operational networks are too coarse and, therefore, miss the horizontal structure and dynamics of cold pools.</p><p>The upcoming measurement campaign FESSTVaL (Field Experiment on Sub-mesocale Spatio-Temporal Variability in Lindenberg) aims to test novel measurement strategies for the observation of previously unresolved sub-mesoscale boundary layer structures and phenomena, such as cold pools. The key component of the experiment during this summer will be a dense network of ground-based measurements within 15 km around the Meteorological Observatory Lindenberg near Berlin. The network of 100 low-cost APOLLO (Autonomous cold POoL LOgger) stations allows to record air pressure and temperature with a spatial and temporal resolution of 100 m and 1 s, respectively. We present first results from a test campaign during last summer that successfully demonstrated the ability of the proposed network stations to observe cold pool dynamics on the sub-mesoscale.</p>