Search results for "Power"
showing 10 items of 5099 documents
Bearing fault detection based on time-frequency representations of vibration signals
2015
To prevent failures of a rolling bearing in the gearbox drive system, acceleration sensors are used to detect fault-related signals of the bearing. It is a big challenge to observe and identify signals caused by bearing defects in the time domain or the frequency spectrum by a conventional Fourier analysis. The time-frequency representation of the fault-related signals implemented by the windowed Fourier transform is studied in this work. It is shown that the fault characteristic frequencies can be clearly identified in the time-frequency spectrum if a fault occurs in the bearing of the gearbox at different speeds. Otherwise, the shaft frequency and its multiples are the main harmonics in t…
Making a difference in women's lives? : case study of women's empowerment programme in Rajasthan
2015
The study is placed in an Indian NGO working for women’s empowerment by the means of informal education, vocational trainings and awareness-raising activities. The goal is to find out to what extent this NGO managed to reach gender justice in practice. The evaluation answers to the questions of what the understanding of gender equality and empowerment was among the people working for the NGO, what the conditions of the chosen participants were and how they influenced participation and then how successful the NGO was in terms of changing gender division of labour and women’s cultural value. My theoretical framework is focused on the Empowerment (GAD) approach, and the gender planning framewo…
Microfinance and women empowerment : to what extent has access to loans led to a change in gender responsibilities at the household level: a case stu…
2014
Master thesis in development management - University of Agder 2014 Microfinance has been recognized internationally as a great strategy in promoting women’s empowerment. Currently development practitioners, international donors, policy makers, Governments, and Non-governmental organizations have introduced microfinance programs to reach out with financial services to the low-income earners, especially women. This is based on the conception that women have better repayment records and also if credit is placed in women’s hands, it leads to improvement in the wellbeing of entire household. This study therefore aimed at assessing the extent to which access to loans by women can lead to a change…
There is more to accommodation of the eye than simply minimizing retinal blur
2017
Eyes of children and young adults change their optical power to focus nearby objects at the retina. But does accommodation function by trial and error to minimize blur and maximize contrast as is generally accepted? Three experiments in monocular and monochromatic vision were performed under two conditions while aberrations were being corrected. In the first condition, feedback was available to the eye from both optical vergence and optical blur. In the second, feedback was only available from target blur. Accommodation was less precise for the second condition, suggesting that it is more than a trial-and-error function. Optical vergence itself seems to be an important cue for accommodation.
Assortment, but not knowledge of assortment, affects cooperation and individual success in human groups
2017
The success or failure of human collective action often depends on the cooperation tendencies of individuals in groups, and on the information that individuals have about each other's cooperativeness. However, it is unclear whether these two factors have an interactive effect on cooperation dynamics. Using a decision-making experiment, we confirm that groups comprising individuals with higher cooperation tendencies cooperate at a higher level than groups comprising individuals with low cooperation tendencies. Moreover, assorting individuals with similar cooperation tendency together affected behaviour so that the most cooperative individuals tended to cooperate more and the least cooperativ…
Radon measurements in the SE and NE flank of Mt. Etna (Italy)
2007
Abstract Soil Radon has been monitored at two fixed sites located in the northeastern and southeastern flank of Mt. Etna. In this study we report the comparison between in-soil Radon concentration trend recorded in the SE flank and that one recorded in the NE one, where an in-soil Radon detection system is operating since 2001. The aim of this work was to implement the investigation area finding a suitable radon detection site, in the south-east flank of Mt. Etna, in order to better understand possible links between Radon anomalies and volcano dynamic. Radon data collected in NE and SE sites were compared with the volcanic tremor, frequency of occurrence of earthquakes and seismic strain-re…
Radiative heat power at Stromboli volcano during 2000–2011: Twelve years of MODIS observations
2012
Abstract Twelve years of night-time MODIS (Moderate Resolution Imaging Spectroradiometer) observations, has been analysed to detect and quantify the radiative heat power emitted by Stromboli volcano (from March 2000 to September 2011). Using an accurate background subtraction of the MODIS signal at 4 μm, we were able to discriminate two main regimes of thermal radiation, related to different levels of volcanic activity. Effusive eruptions (occurred on December 28, 2002 and February 27, 2007) radiated at an average of ~ 186 MW with a frequency of alert detection of 50–95%. Conversely, during the typical strombolian activity, an average of ~ 9 MW is radiated, with a frequency of alert detecti…
Melt extraction and accumulation from partially molten rocks
2004
Current models for melt segregation and ascent are not adequate to accurately describe transport and accumulation in combination. We propose that transport is discontinuous and in batches, and that accumulation occurs by stepwise merging of batches. A simple numerical model of jostling spheres that merge when they touch was used to represent stepwise accumulation and transport of batches by propagation of hydrofractures. Results of the numerical model indicate that such a system may quickly develop into a self-organised critical (SOC) state. In this state, the distribution of melt batch volumes can be described by a power law, with an exponent m that lies between 2/3 and 1. Once a self-orga…
Sediment transport mechanisms and selective removal of soil particles under unsteady-state conditions in a sheet erosion system
2022
Abstract Selective removal of particles and nutrients by water erosion is a key factor in soil erosion studies. Most agricultural soils are located on gentle slopes where fertility is high; however, until now, the main attention on sediment transport mechanisms was paid to high-slope gradients, where soil erosion is intense, but soils are less productive. Despite the importance of sediment size distribution (SSD) and transport mechanisms under unsteady-state conditions, few studies have been done on this issue. Higher sediment concentrations in the early stages of the runoff indicate the need to deal with unsteady-state conditions. To address this issue, sheet erosion experiments were done …
Alternative energy scenarios for small islands: A case study from Salina Island (Aeolian Islands, Southern Italy)
2012
Abstract The Aeolian archipelago is made up of seven main islands situated in the Tyrrhenian sea (Sicily Italy). They represent a suitable scenario for the development of a sustainable energy production system, that could easily be reproduced on other Mediterranean Islands. The fact that these islands depend on the mainland for energy supplies and the high cost of bringing fuel in tanker boats are factors that should strongly encourage the use of renewable energy source technologies. Taking into account the European Commission guidelines, this paper sets out to evaluate potential energy production using photovoltaic and small scale wind power, in order to verify their contribution to overal…