Search results for "ground"

Life cycle analysis of innovative building materials based on circular coffee ground supply chain

2022

The construction sector is widely recognized as one of the most polluting mainly due to its intensive exploitation of natural resources and large energy consumption to produce traditional building materials. In the last years, alternative building materials have been developed with the aim to reduce the environmental burden of this sector. In particular, the use of geopolymer mortars as alternative cementitious materials is gaining increasing acceptance among scientists. Numerous laboratory studies demonstrate their suitability for construction applications, highlighting the potential environmental benefits that can be obtained from their large-scale production. This study aims to perform a…

Android tool to evaluate grounding resistance

2015

In the absence of sources of rapidly varying field, the study of the potential distribution determined, in a linear medium, by a geometrically complex grounding may be conducted by applying the method of superposition of the effects, known as method of subareas of Maxwell. Such approach can be usefully employed in an educational tool intended for students of electrical engineering.

Safety Concerns on Ground Fault Application Transfer Phenomenon in HV Installations

2007

When a fault to ground occurs in HV/MV substations supplied by a combined overhead-cable line, most of the fault current can be transferred and injected into the soil several kilometers far away from the fault location. This phenomenon is called "fault application transfer" and mostly concerns transition stations, where cables are connected to the overhead line. If the transition station is a dead-end steel pole structure, usually accessible to the general public, the local ground electrode could be inadequate to maintain ground potential rise within safety limits. Hence, dangerous touch and step voltages may appear at exposed locations. In the paper results of various computer simulations …

Ground Fault Current Distribution in Substations Supplied by Nonuniform Multi-Section Lines

2007

he paper presents a general method for computing the distribution of substation ground fault current. The feeding line can be entirely homogeneous along its whole length or consisting of two or more different sections, i.e. part overhead and part underground cable. Based on the two-port theory, the proposed method allows to take into account all the relevant conductively and inductively coupled parameters which take part to the distribution of the fault current and can be easily implemented in a computer program. Numerical examples demonstrate the high efficiency of the proposed method.

Practical tables for the design of the grounding systems in distribution networks in presence of metallic interconnection

2009

The present paper deals with the dependence of the ground current, due to a single-line-to-ground fault in a secondary substation, on the electrical and geometrical parameters of a Medium Voltage distribution network in which a metallic interconnection between the grounding systems is realized. Examining different situations, some easy-to-use tables are provided for a practical approach to the design of the ground electrodes of the secondary substations in these networks. The relevance of the work is due to the lack in the international standards of specific indications on how to consider the presence of the interconnection elements in distribution networks.

Guidelines and Conceptual Design of the Grounding System of the DTT Experimental Facility

2022

The Divertor Tokamak Test (DTT) is an experimental nuclear fusion reactor currently under construction at the ENEA research center in Frascati and whose first plasma is expected in 2025. The present article shows the conceptual philosophy and the guidelines behind the design of the grounding system of the DTT. The article focuses on the main target of the grounding system and on the main technical standards to refer to for the design.

Rateless Codes Performance Analysis in Correlated Channel Model for GEO Free Space Optics Downlinks

2012

Fading mitigation coding techniques for space to ground free space optical communications

2014

Grounding concepts as emerging clusters in multiple conceptual spaces

2018

A novel framework for symbol grounding in artificial agents is presented, which relies on the key idea that concepts "emerge" implicitly at the perceptual level as clusters of points with similar features forming homogeneous regions in multiple perceptual Conceptual Spaces (pCS). Such spaces describe percepts such as color, texture, shape, and position that in turn are the properties of the objects populating the agent's environment. Objects are represented in a suitable object Conceptual Space where all their features are composed together again using clustering in pCSs. Symbols will be learned from such a tensor space. A detailed description of both the framework and its theoretical found…

Palmprint principal lines extraction

2014

The palmprint recognition has become a focus in biological recognition and image processing fields. In this process, the features extraction (with particular attention to palmprint principal line extraction) is especially important. Although a lot of work has been reported, the representation of palmprint is still an open issue. In this paper we propose a simple, efficient, and accurate palmprint principal lines extraction method. Our approach consists of six simple steps: normalization, median filtering, average filters along four prefixed directions, grayscale bottom-hat filtering, combination of bottom-hat filtering, binarization and post processing. The contribution of our work is a new…