Search results for " void"

Effect of Polarity Reversal on the Partial Discharge Phenomena

2020

In the field of High Voltage Direct Current (HVDC) transmission, the space charge accumulation phenomenon and the Partial Discharges (PD) phenomena are considered the main causes of dielectric ageing. During the years, the degradation effect of both phenomena under constant DC stress has been widely studied by several researchers. In case of polarity reversal, typically carried out to control bi-directional power flow between interconnected High Voltage transmission systems, the space charge movement may not synchronously follow the electric field polarity. This could make the moment of reversing polarity a very critical one, where space charge injected during preceding polarity produces hi…

Acoustic Wave Behavior in a Specimen Containing an Air Void Defect

2019

The PEA method is the most used technique for the space charge measurements. As is well known, this method uses pressure waves to detect the charges accumulated in solid dielectrics. Based on its working principle, the generated acoustic waves travel within PEA cell and the specimen under test in order to be finally detected by the piezoelectric sensor. For a multilayer specimen and, in particular, in case of different materials that make up the specimen, the acoustic wave reflection is inevitable. Considering that, in several cases, the reflected waves could be detected by the piezoelectric sensor before than the main signals, the PEA cell output profile could results distorted. Based on t…

Water retention and swelling behaviour of granular bentonites for application in Geosynthetic Clay Liner (GCL) systems

2016

Geosynthetic Clay Liner (GCL) systems are used as efficient hydraulic barriers in landfills for the disposal of hazardous municipal wastes. Along with geotextiles, bentonite materials are chosen as one of the primary components of GCLs due to their high retention, adsorption, and swelling capacities. GCLs are manufactured using bentonites at a high total suction and hydrated through the uptake of liquid from the subsoil and the confined material as soon as they are installed. Bentonites may exhibit considerable volume change upon wetting. Depending on the confinement stress, the void ratio may significantly increase with a decrease in suction, particularly at higher degrees of saturation. T…

Impact of cosmic inhomogeneities on SNe observations

2009

We study the impact of cosmic inhomogeneities on the interpretation of SNe observations. We build an inhomogeneous universe model that can confront supernova data and yet is reasonably well compatible with the Copernican Principle. Our model combines a relatively small local void, that gives apparent acceleration at low redshifts, with a meatball model that gives sizeable lensing (dimming) at high redshifts. Together these two elements, which focus on different effects of voids on the data, allow the model to mimic the concordance model.

Architettura in alzato. Questioni di territorio, paesaggio, ambiente

2021

Negata alla tipologia l’architettura del Sud nel saggio riconosce una specifica identità e perfetta eccezionalità nell’essenza del luogo. Se la facciata istituisce un rapporto con l’estetica del paesaggio, i temi che essa sottende definiscono altre significative relazioni. L’ordinamento logico delle membrature, la chiarezza geometrica e il rigore dei rapporti rimandano ad una architettura che si misura, ed è misura stessa, del territorio e della sua morfologia. A sua volta, lo spessore della facciata esprime la relazione con l’ambiente e interpreta in maniera poetica i condizionamenti climatici, intervenendo sul controllo della luce, sui vuoti nei paramenti murari, sulla determinazione dell…

The Line: committing and commemorating ‘the crime without a name’

2018

This article analyses Gina Shmukler’s verbatim play The Line (2012) and argues for another look at the testimonies captured from witnesses, survivors and perpetrators of the violence targeting foreign and perceived as foreign persons in South Africa that escalated in 2008 and in 2015. It is a narrative analysis of the play that uses Gregory H. Stanton’s Ten Stages of Genocide model and the United Nations Convention on Genocide to investigate the theatrical representation of the violence. This account argues that the events that are captured in the play and that inspired it should be reconsidered as acts of genocide. In the absence of an official acknowledgement of the events as genocide, pe…

A study on Norwegian companies in China: Challenges & successful strategies

2016

Master thesis Business Administration BE501 - University of Agder 2016 This paper examines what governmental and cultural challenges Norwegian companies face when entering and doing business in China. In addition, this paper also discusses what strategies to implement to overcome these challenges. With China becoming a bigger player in the global marketplace, this is an important matter not only for companies across the world but also for Norwegian companies. Through a qualitative research method with semi-structured interviews, the research is conducted on four Norwegian companies who does business in China. The findings shows that there are many variables affecting the choice of entry mod…

Filling the void about sperm function knowledge and how the -omics approach can close the circle.

2013

Discrepancy between power-Doppler voiding urosonography and voiding cystourethrography is not relevant for the management of primary vesicoureteric r…

2006

The aim of this study was to assess if discrepancy between power-Doppler voiding urosonography (PD-VUS) and voiding cystourethrography (VCUG) affects the management of patients with primary vesicoureteric reflux (VUR).Fifty-six children with suspected or known VUR were assessed both by PD-VUS and VCUG. Two independent observers, both pediatric surgeons, each aware of the results of only one imaging modality, advised children's management according to present care standards. Agreement between diagnostic findings at the two imaging modalities and between therapeutic advice of the two observers was evaluated using kappa statistics.PD-VUS diagnosed VUR in 3 patients and 6 ureteral units more th…

Fundamental characterisation of reclaimed asphalts: The importance of testing homogeneous specimens

2013

This study highlights the importance of defining appropriate specimen manufacturing procedures when assessing the fundamental properties of reclaimed asphalt (RA) mixes for further modelling purposes. Two gyratory compactor procedures were used: the first leading to specimens with a non-uniform air voids distribution and the second tailored to obtain homogeneous specimens. The study was performed by using three stone mastic asphalts incorporating up to 30% of RA but designed to have identical properties. A detailed characterisation of the loose mixes and binders, an X-ray computer tomography micro-structural study of the manufactured specimens and a further mechanical characterisation showe…