Search results for "Enna"

Performance Analysis of Cooperative V2V and V2I Communications Under Correlated Fading

2019

Cooperative vehicular networks will play a vital role in the coming years to implement various intelligent transportation-related applications. Both vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications will be needed to reliably disseminate information in a vehicular network. In this regard, a roadside unit (RSU) equipped with multiple antennas can improve the network capacity. While the traditional approaches assume antennas to experience independent fading, we consider a more practical uplink scenario where antennas at the RSU experience correlated fading. In particular, we evaluate the packet error probability for two renowned antenna correlation models, i.e., cons…

PHASER – A Phase-Shifting Antenna for Low-Power Directional Communication

2017

This paper describes the design and empirical evaluation of PHASER — a mote prototype for low-power directional communication in wireless sensor networks. PHASER has a modular design that includes three components: a low-power radio, an RF signal processing chip, and two off-the-shelf antennas. Directional communication is achieved by splitting the output signal from the low-power radio chip and controlling programmatically the phase of each signal as it transmitted to each antenna. The net effect of controlling the phase of the signals is that they generate patterns of constructive and destructive interference as signals propagate. PHASER is well-suited for wireless sensor networks as it d…

The Large Area Detector onboard the eXTP mission

2018

The eXTP (enhanced X-ray Timing and Polarimetry) mission is a major project of the Chinese Academy of Sciences (CAS) and China National Space Administration (CNSA) currently performing an extended phase A study and proposed for a launch by 2025 in a low-earth orbit. The eXTP scientific payload envisages a suite of instruments (Spectroscopy Focusing Array, Polarimetry Focusing Array, Large Area Detector and Wide Field Monitor) offering unprecedented simultaneous wide-band X-ray spectral, timing and polarimetry sensitivity. A large European consortium is contributing to the eXTP study and it is expected to provide key hardware elements, including a Large Area Detector (LAD). The LAD instrumen…

Baseline design of the filters for the LAD detector on board LOFT

2014

The Large Observatory for X-ray Timing (LOFT) was one of the M3 missions selected for the phase A study in the ESA's Cosmic Vision program. LOFT is designed to perform high-time-resolution X-ray observations of black holes and neutron stars. The main instrument on the LOFT payload is the Large Area Detector (LAD), a collimated experiment with a nominal effective area of ~10 m 2 @ 8 keV, and a spectral resolution of ~240 eV in the energy band 2-30 keV. These performances are achieved covering a large collecting area with more than 2000 large-area Silicon Drift Detectors (SDDs) each one coupled to a collimator based on lead-glass micro-channel plates. In order to reduce the thermal load onto …

The silver collection of San Gennaro treasure (Neaples): A multivariate statistic approach applied to X-ray fluorescence data

2021

Abstract In this work we report an X-ray fluorescence spectroscopy (XRF) study combined with a multivariate approach allowing to detect compositional differences and similarities among the alloys used in realization of silver collection of San Gennaro items collection. The San Gennaro treasure in Naples (Italy) represents, in fact, one of the most important silver collections in the world. The classification of the collection items is very complex, not only for the large number of objects, but also in consideration that between 1600 and 1700, in Naples, more than 350 laboratories were active, most of them specialized in specific art of work. As a consequence, a given collection object could…

Per l'interpretazione di Sisenna, "Miles. libri" fr. 6 P. = 4 B. H.

2002

Empowered by stigma? Pioneer organic farmers' stigma management strategies

2019

Abstract Pioneers of organic farming often faced social challenges as their innovative ideas on agriculture not only encountered opposition in the conventional farming community, but led to stigmatization of organic farmers as social deviants. In this study, we examine what kind of stigma management strategies pioneer organic farmers engage with in order to cultivate an alternative positive image of themselves. Our research is based on the interviews with 14 pioneer organic farmers. Based on a qualitative analysis of the interviews, we provide a model of those strategies that the creation from a stigmatized to valued identity requires. Our study increases the understanding of the institutio…

Influence of structure on the tissue dynamics of the human soleus muscle observed in MRI studies during isometric contractions.

2006

This article investigates how the internal structure of muscle and its relationship with tendon and even skeletal structures influence the translation of muscle fiber contractions into movement of a limb. Reconstructions of the anatomy of the human soleus muscle from the Visible Human Dataset (available from the National Library of Medicine), magnetic resonance images (MRI), and cadaver studies revealed a complex 3D connective tissue structure populated with pennate muscle fibers. The posterior aponeurosis and the median septum of the soleus form the insertion of the muscle and are continuous with the Achilles tendon. The distal extremities of the pennate muscle fibers attach to these struc…

Koulukiusaamisen ennaltaehkäseminen osana luokan toimintakulttuuria

2010

Teimme tapaustutkimuksen alkuopetuksen luokkaan, jossa tutkimme paljon huomiota saanutta ilmiötä koulukiusaamista. Tutkimme mitä kiusaaminen on oppilaiden ja opettajan mielestä, esiintyykö tutkimusluokassa kiusaamista, miten siihen puututaan ja kuinka luokanopettaja ennaltaehkäisee koulukiusaamisen syntymistä. Käytimme tutkimiseen kouluetnografista lähestymistapaa, johon sisältyi havainnointia, haastatteluja sekä sosiometrisen mittauksen toteuttaminen luokassa. Tutkimuksen tulokset osoittivat koulukiusaamisen olevan fyysistä tai henkistä kiusaamista, se voi olla näkyvää tai ulospäin hyvin huomaamatonta. Löysimme sosiometrisen mittauksen avulla kaksi kiusattua, joten sosiometrinen mittaus os…

The impact of spatial correlation on the statistical properties of the capacity of nakagami-m channels with MRC and EGC

2011

Published version of an article published in the journal: EURASIP Journal on Wireless Communications and Networking. Also available from the publisher at: http://dx.doi.org/10.1186/1687-1499-2011-116. OA In this article, we have studied the statistical properties of the instantaneous channel capacitya of spatially correlated Nakagami-m channels for two different diversity combining methods, namely maximal ratio combining (MRC) and equal gain combining (EGC). Specifically, using the statistical properties of the instantaneous signal-to-noise ratio, we have derived the analytical expressions for the probability density function (PDF), cumulative distribution function (CDF), level-crossing rat…