Search results for "Metro"
showing 10 items of 620 documents
The metrological characterization of the static meters for reactive energy in the presence of harmonic distortion
2007
For the electricity metering for billing purposes in distribution systems, the static meters are substituting the traditional inductive meters. Thus, the evaluation of the performances of such equipments is required, also in the presence of disturbances affecting the power systems. With respect to this, this paper analyzes the main aspects related to the metrological characterization of the static meters for reactive energy in the presence of harmonic distortion. Particular attention is given to the reference standard meters, that are not considered by the actual in-force Standards. The analysis is supported by several experimental tests.
An harmonic test condition for the metrological characterization and the operating principle identification of reactive static meters
2008
This paper faces the problem of the metrological characterization of the static meters for reactive energy in the presence of harmonic distortion. Starting from the only available accuracy test condition in the presence of harmonics introduced in the Standards for active static meters, an experimental approach is proposed for the verification of such meters in the presence of harmonic distortion, as well as for the individuation of their operating principle. A theoretical validation of the obtained results is presented by means of a comparison with a standard and a commercial static meter with a known operating principle.
Development of a high-accuracy PC-based wattmeter with commercial data acquisition boards
2011
This paper presents the development of a high accuracy sampling wattmeter, which makes use of two commercial data acquisition boards (DAQs) connected to a common personal computer. Commercial software is also used for data processing and implementation of the virtual instrument. The set up of the PC-based wattmeter is described and a preliminary evaluation of its metrological performances is made by means of two series of experimental tests, which were carried out with an electric power standard and a high performance multifunction calibrator. © 2011 IEEE.
A PC-based wattmeter for accurate measurements in sinusoidal and distorted conditions: Setup and experimental characterization
2012
This paper presents the development of a high-accuracy sampling wattmeter, which can be employed with both sinusoidal and distorted input signals. The proposed personal computer (PC)-based system is a simple, portable, and low-cost solution because it is based on two commercial data acquisition boards connected to a common PC. Owing to this solution, the voltage is sensed directly, avoiding expensive voltage dividers, while the current is sensed by means of a noninductive current shunt. Commercial software is also used for data processing and implementation of the virtual instrument. The setup of the PC-based wattmeter is described, with a detailed description of the correction strategy of …
The Area Of The Strait Reading Theories And Strategies For A Metropolitan Dimension
2016
Abstract Extending across a peninsular strip going from Gioia Tauro to Melito Porto Salvo on the Calabrian side, and from Milazzo to Giardini Naxos on the Sicilian side, the Strait of Sicily sees theAspromonte massif and the Peloritani mountain range as two facing stage sets of land sketching in the gulf a water piazza of a landscaping room. Described in the proposal by Giuseppe and Alberto Samona, Ludovico Quaroni, Antonio Quistelli, Sergio Musmeci, Paolo D’Orsi Villani and Leonardo Urbani, it outlines, in the county seats of Reggio Calabria and Messina, the prevalence of a Euclidean space, identifiable in the exact metrics given by the recurrence of the measuring step of the blocks drawn …
The joy of teaching and learning in academia – teachers’ perspectives from three countries
2021
All over the world, the educational landscape has changed dramatically over the last year, impacting the way we teach and learn. It is time for reflecting and searching for new ways to support each other, during these pandemic times and beyond; time to co-construct creative partnerships and to innovate new ways to co-create. Change is an inevitable part of teaching and learning but the adaptations currently required are of unprecedented scale. How can we teach and learn with joy in today’s academia? How can we support each other, as teachers, in more creative ways? These two reflective questions were at the base of the study, which was conducted by university teachers from three countries: …
The Role of Geographic Technologies in the Measure of Spatial Equity. Twenty-First Century Solutions for Old Geographical Issues
2019
In Western societies, the development of the Welfare State has been accompanied by the proposal of different models of spatial organisation that help to improve spatial equity, this being a priority object of all public policy because it clearly contributes to the achievement of a greater social cohesion. Geography has contributed, from Christaller to the present, to propose territorial models that help to optimise the location of activities and services, using spatial statistics and digital cartography. At present, the study of spatial equity is again receiving the attention of the academy, in particular as regards the provision of public services and facilities in urban and metropolitan a…
Presión arterial: ¿esfigmomanómetro manual o digital?
2008
El presente es un estudio prospectivo y comparativo entre la medición de la presión arterial obtenida de manera manual con esfigmomanómetro aneroide y la obtenida mediante monitor automático. El desarrollo de la práctica se realizó sobre un grupo de 100 pacientes hospitalizados en el servicio de Neurocirugía y Otorrinolaringología del Consorcio Hospital General de Valencia durante el primer trimestre del año 2007, mediante mediciones secuenciales y efectuadas por el mismo observador con ambos aparatos bien calibrados. Se observó mediante el método de correlación bivariada de Pearson que no existen diferencias estadísticamente significativas entre las presiones tomadas por ambos aparatos det…
Crisis económica y desarrollo metropolitano. Una propuesta de investigación
2015
[EN] The metropolitan areas have undergone deep transformations linked to neo-liberal globalization, whose effects have been disseminated with uneven intensity depending on their specific local paths. The current economic crisis and the austerity policies applied in the European periphery shows their contradictions and causes new social and spatial asymmetries that are best reflected in these large urban areas, modifying their development paths. This paper proposes an interpretation on the territorial dimension of the economic crisis, discusses some of its main metropolitan manifestations and proposes various lines of research. The effect of the financialisation in the production of urban s…
Gigabit Ethernet backbones with active loops
2001
The current standard Ethernet switches are based on the Spanning Tree (ST) protocol. Their most important restriction is that they can not work when the topology has active loops. In fact, the ST protocol selects a tree from the real topology by blocking the links that are not involved in the tree. This restriction produces a network traffic unbalancing behavior saturating those link near the root switch while rest of links will be idle or with a very low utilization. This paper proposes a new transparent switch protocol for Gigabit Ethernet backbones that considerably improves the performance of current ones. The proposed protocol is named ALOR for Active Loops and Optimal Routing. ALOR pr…