989 research outputs found
ReLambro. Il fiume nuova infrastruttura ecologica della metropoli milanese
Lo studio raccoglie gli esiti di tre anni di progetto per la rete ecologica del Lambro Milanese cofinanziato da Fondazione Cariplo, con partner Politecnico di Milano, Ersaf (capofila), Legambiente Lombardia, PLIS Media Valle Lambro. Sviluppato in forma multidisciplinare come un documento di ricerca e azione, si propone con un vero e proprio documento di riferimento per tutti i soggetti che vogliono operare sul Lambro, o più in generale in ambiti fluviali in contesti urbani, fornendo uno strumento pratico da utilizzare per le azioni di riqualificazione fluviale e ambientale, nell’ottica di migliorare la funzionalità eco-sistemica del territorio e costruire e rafforzare la connessione ecologica a tutela della biodiversità
Theory and Application of Roscoe Pound\u27s Sociological Jurisprudence: Crime Prevention or Control?
The current interest in reforming the administration of justice has been triggered by a number of factors including the 1967 report of the President\u27s Commission on Law Enforcement and the Administration of Justice and the treatment afforded arrestees during the civil disorders of the past few years. The nation is alarmed at the reported annual increases in crime, and this alarm was manifested in the 1968 presidential election when law and order became a major issue. Superficially the answer may seem clear: more effective enforcement of the law and, when necessary, more stringent laws. The critical issue, however, is a jurisprudential-philosophical one: ought the proper approach to crime essentially be its prevention through methods such as the rehabilitation of criminal offenders, or its control through efficient administrative procedures? This is not a new question in jurisprudence, but it remains an important and unresolved one. This article will examine an analytical approach to this problem which was developed and applied by Roscoe Pound, one of America\u27s most eminent jurists. After describing and interpreting Pound\u27s concept of sociological jurisprudence, we will relate it generally to the reform of criminal justice administration and analyze Pound\u27s attempt to apply his theory as -Director of the Cleveland Crime Survey of 1921. Finally, we will compare the recommendations of that Cleveland study and the recent report of the President\u27s Commission in a modest effort to assess their impact on the administration of criminal justice and to draw some lessons for future reform endeavors
Innovative 3-D Printing Processing Techniques for Flexible and Wearable Planar Rectennas
This work demonstrates the use of a low-cost, lossy, flexible substrate processed by novel 3-D printing techniques which significantly mitigate its intrinsic losses, thus providing performance comparable to those of traditional substrates. These processing techniques are applied to both microstrip and coplanar waveguide structures; they are first derived theoretically, starting from the electromagnetic theory of modes propagation, then numerically validated by full-wave analysis, and finally experimentally verified. The design of a miniaturized 868 MHz rectenna, adopting a coplanar-fed patch antenna based on the proposed fabrication approach, is presented. By means of nonlinear/electromagnetic co-design, the antenna is directly matched to the rectifier. A 30-dB power range starting from -20 dBm is considered. Direct matching allows to get rid of a dedicated matching network and its associated losses, resulting in a slight efficiency increase and a significant reduction of the overall dimensions. Finally, the 3-Dprinted prototype is presented: the overall rectenna performance proves that design freedom enabled by 3-D printing paves the way to the use of low-cost flexible dielectric materials, even with poor electromagnetic properties, to realize wearable battery-free wireless nodes
Focusing RF-on demand by logarithmic frequency-diverse arrays
The radiating systems exploiting the frequency diversity of the antennas are powerful architectures, that can have a big impact on wireless power transmission applications, but their characterization is merely theoretical. This paper offers a deep and critical numerical analysis of frequency- diverse arrays and shows the advantages of the family with logarithmic distribution of the frequency for radio-frequency energy focusing goals. For the first time, these systems are analyzed through a Harmonic Balance-based simulation combined with the full-wave description of the array made of eight planar monopoles: the rigorous results confirm the potentialities of these complex radiating systems, in particular show how the time-dependency of the radiating mechanism can be favorably deployed
Modeling and simulation of nuclear hybrid energy systems architectures
The transition toward a low-carbon energy system and the increasing penetration of variable renewable energy (VRE) sources translate into a pressing need for dispatchable and low-carbon power sources. Nuclear hybrid energy systems (NHES) exploit the synergies between nuclear power and other energy sources together with energy storage devices and a variety of electric and non-electric applications. The expected benefits range from a high flexibility being able to supporting an increasing penetration of the VRE while complying with the grid demand and constraints to an increased profitability brought by the production of commodities beyond electricity (e.g., hydrogen, heat, etc.). A dedicated framework must be developed to evaluate different NHES configurations, particularly with regard to the complex interconnections among the tightly coupled components. In this work, illustrative examples of NHES components were selected and modeled with the object-oriented modeling language Modelica and implemented in the Dymola simulation environment. The technologies considered in this study are a Small Modular Reactor (SMR) based on pressurized water technology, a thermal energy storage (TES) system, and an alkaline electrolyzer for hydrogen production. The dynamic models are then collected in a new Modelica library and assembled into a variety of NHES topologies using a plug-and-play approach. The time-dependent behavior of the NHES layout can be simulated under different operational contexts, enabling the monitoring of key process variables, supporting system design, exploring alternative control strategies, and analyzing different scenarios. The NHESs are investigated in two exemplary scenarios – one representing typical load conditions and the other featuring high VRE penetration – in order to demonstrate the viability of the proposed approach as an initial effort toward the development of a holistic framework for analyzing NHES. The dynamic models effectively met the analysis requirements, for instance, by tracking the production of commodities throughout each operational transient, which is an essential result for evaluating the performance of NHES. In this regard, efficiency is adopted as the figure of merit to compare the different NHES architectures, with simulation results indicating significant overall efficiency improvements in NHES incorporating TES and using nuclear heat to drive non-electric applications
An all-in-one dual band blade antenna for ads-b and 5g communications in uav assisted wireless networks
This paper is aimed at the characterization and manufacturing of an SMA coaxial fed com-pact blade antenna with dual frequency characteristics for broadband applications on board of Unmanned Air Vehicles (UAVs). This antenna is linearly polarized, and it combines the benefits of Automatic Dependent Surveillance-Broadcast (ADS-B) and 5th Generation (5G) communications in one single element, covering both the 1.030–1.090 GHz and the 3.4–3.8 GHz bands thanks to a bent side and a ‘C’ shaped slot within the radiation element. Starting from the simulation outcomes on an ideal ground plane, the results are here extended to a bent ground plane and on two UAV com-mercial CAD models. Details of manufacturing of the antenna in both aluminium and FR-4 substrate materials are presented. The comparison between measurements and simulations is discussed in terms of return loss, bandwidth, gain, and radiation pattern. Results show an antenna with a low profile and a simple structure that can be employed in various wideband communication systems, suiting future UAV assisted 5G networks while being perfectly compliant with forthcoming ADS-B based Detect-And-Avoid (DAA) technologies in Unmanned Aerial Traffic Management (UTM)
Microwave Devices for Wearable Sensors and IoT
The Internet of Things (IoT) paradigm is currently highly demanded in multiple scenarios and in particular plays an important role in solving medical-related challenges. RF and microwave technologies, coupled with wireless energy transfer, are interesting candidates because of their inherent contactless spectrometric capabilities and for the wireless transmission of sensing data. This article reviews some recent achievements in the field of wearable sensors, highlighting the benefits that these solutions introduce in operative contexts, such as indoor localization and microwave sensing. Wireless power transfer is an essential requirement to be fulfilled to allow these sensors to be not only wearable but also compact and lightweight while avoiding bulky batteries. Flexible materials and 3D printing polymers, as well as daily garments, are widely exploited within the presented solutions, allowing comfort and wearability without renouncing the robustness and reliability of the built-in wearable sensor
Large-scale shifts in phytoplankton groups in the Equatorial Pacific during ENSO cycles
The El Niño Southern Oscillation (ENSO) drives important changes in the marine productivity of the Equatorial Pacific, in particular during major El Niño/La Niña transitions. Changes in environmental conditions associated with these climatic events also likely impact phytoplankton composition. In this work, the distribution of four major phytoplankton groups (nanoeucaryotes, Prochlorococcus, Synechococcus, and diatoms) was examined between 1996 and 2007 by applying the PHYSAT algorithm to the ocean color data archive from the Ocean Color and Temperature Sensor (OCTS) and Sea-viewing Wide Field-of-view Sensor (SeaWiFS). Coincident with the decrease in chlorophyll concentrations, a large-scale shift in the phytoplankton composition of the Equatorial Pacific, that was characterized by a decrease in Synechococcus and an increase in nanoeucaryote dominance, was observed during the early stages of both the strong El Niño of 1997 and the moderate El Niño of 2006. A significant increase in diatoms dominance was observed in the Equatorial Pacific during the 1998 La Niña and was associated with elevated marine productivity. An analysis of the environmental variables using a coupled physical-biogeochemical model (NEMO-PISCES) suggests that the Synechococcus dominance decrease during the two El Niño events was associated with an abrupt decline in nutrient availability (−0.9 to −2.5 μM NO3 month−1). Alternatively, increased nutrient availability (3 μM NO3 month−1) during the 1998 La Niña resulted in Equatorial Pacific dominance diatom increase. Despite these phytoplankton community shifts, the mean composition is restored after a few months, which suggests resilience in community structure
Comparison between BNP values measured in capillary blood samples with a POCT method and those measured in plasma venous samples with an automated platform
Letter to the Editor. Our data suggest that it is possible
to measure BNP in fresh finger-stick samples of capillary
whole blood with an acceptable reproducibility,
and within 10 – 20 min to obtain results close correlated
to those measured by the automated platform in plasma
blood samples collected from a vein. The measurement
of BNP in fresh finger-stick samples of capillary whole
blood with this POCT method is in particular indicated for
the management of HF patients at home and for the BNP
assay in neonates and children
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