Search results for "Power"
showing 10 items of 5099 documents
A portable system for multiple parameters monitoring: towards assessment of health conditions and stress level in the automotive field
2019
In this work, an electronic portable combo system able to synchronously acquire multiple signals, e.g. electrocardiographic (ECG), photoplethysmographic (PPG) and breathing waveforms, is presented. The realized system is also capable of showing in real time some physiological parameters which can be used for assessing health/stress status of the volunteer, such as heart rate and breathing frequency and their trends over time. Thanks to the use of non-invasive PPG probes, of batteries as power supply, and to the possibility to add in the future additional sensors to acquire other signals, the system could also be employed inside vehicles for assessing the status of the driver. Finally, the r…
A Cross-Sectional Analysis of Growth and Profit Rate Distribution: The Spanish Case
2022
We analyse the time evolution of the empirical cross-sectional distribution of firms’ profit and growth rates. In particular, we analyse the conditional properties of the empirical distributions depending on the size of the firms and the business cycle phase. In order to do so, we employ the Laplace distribution as a benchmark, further considering the Subbotin and Asymmetric Exponential Power (AEP hereafter) distributions, to capture the potential asymmetry and leptokurtosis of the empirical distribution. Our results show that the profit rates of large firms are characterised by an asymmetric Laplace distribution with parameters largely independent of the business cycle phase. Small firms, …
Ethical Ratings: A Systematic Analysis Oriented to Business Economics
2013
Abstract In a previous study we have researched the causes of the current global crisis, which manifests itself in financial terms, but whose origin is due to the ethical model of reference. Following these ethical issues, the aims and topics of the present paper are: producing a systematic analysis of the ethical indicators used in the current international practices; extrapolating the ethical ranking models with a high relevance in Business Economics and highlighting the strong limits of the methodology in current use.
Hedging spark spread risk with futures
2018
Abstract This paper discusses the spark spread risk management using electricity and natural gas futures. We focus on three European markets in which the natural gas share in the fuel mix varies considerably: Germany, the United Kingdom, and the Netherlands. We find that spark spread returns are partially predictable, and consequently, the Ederington and Salas (2008) minimum variance hedging approach should be applied. Hedging the spark spread is more difficult than hedging electricity and natural gas price risks with individual futures contracts. Whereas spark spread risk reduction for monthly periods produces values of between 20.05% and 48.90%, electricity and natural gas individual hedg…
A Power Sector in Transition Understanding Transition Towards a Cleaner Grid and how Distributed Energy Resources Affect the Design and Operation of …
2018
Important changes in the supply and the demand side of electricity apparatus are now underway, triggered by a combination of drivers dramatically affecting the transmission sector of power systems: greenhouse gas emissions, distributed generation, energy efficiency and the full integration of the European energy market. A variety of accelerating factors - including active consumer, aggregators, energy storage, e-vehicles, etc..- are creating a new era for the many stakeholders, incl. system operators, regional entities, industry and consumer organizations, producers or their trade bodies, Regulators, public decision makers and the society at large. Entraining this background, ENTSO-E and th…
EU transition in power sector
2019
Abstract In the past, much of Europe’s electricity grid network has been designed in consideration of the locations of conventional generation plants. However, a large share of today's renewables production – notably variable wind and solar – does not correspond to this grid architecture. Interconnectors, in addition to internal infrastructure, are key to creating new electricity corridors to connect areas of surplus to areas of scarcity. In this context, in 2014 the European Council, in recognizing that a fundamental role of transmission infrastructure is to enable the integration of areas of high renewable energy potential with main consumption areas, endorsed the proposal by the European…
Digital Trace Data in the Study of Public Opinion
2016
In this article, we examine the relationship between metrics documenting politics-related Twitter activity with election results and trends in opinion polls. Various studies have proposed the possibility of inferring public opinion based on digital trace data collected on Twitter and even the possibility to predict election results based on aggregates of mentions of political actors. Yet, a systematic attempt at a validation of Twitter as an indicator for political support is lacking. In this article, building on social science methodology, we test the validity of the relationship between various Twitter-based metrics of public attention toward politics with election results and opinion pol…
On the harvest of rainfall energy by means of piezoelectric transducer
2013
In this paper a detailed study on the harvest of the energy contained in rainfall by means of piezoelectric transducers is presented. Diverse studies agree on the level of suitable generated voltage on the electrodes of a piezoelectric transducer subjected to rainfall, but a complete characterization on the supplied power is still missing. This work, in order to limit optimistic forecasts, takes into account the behavior of the transducers subjected to real and also artificial rainfall, condition that has shown promising behavior in laboratory. In order to increase the energy harvesting and also define its limits different loads have been taken into account. Only commercial transducers have…
Medical Attendance in Air Transportation of Patients
1985
SummaryAir transportation missions of seriously ill or injured patients are subdivided into rescue missions and medical evacuation missions. In 1981, for rescue missions, 29 stationed rescue helicopters were available with an operation radius of 50 km. Their task consisted of securing the primary care for vital risk patients as soon as possible. Medical evacuation missions were realized by helicopter, ambulance aircraft, and airliner. Before take-off a medical briefing was held to diminish the transport-trauma. Patients with cardiopulmonary insufficiency are at risk as simultaneous appearance of acceleration, climbing rate, falling cabin pressure and emotional stress may produce serious com…
Psychophysical response to electrocutaneous stimulation.
1984
A method is presented to determine a reliable stimulus-sensation relationship particularly suitable for electrocutaneous stimulation. An experimental intensity-discrimination curve was obtained through simple psychophysical comparison tasks, and sensory response was inferred from integration of a JND's density function. The psychophysical response resembles a power law, although departures cannot be described in terms of a unique exponent. An estimate of binary information capacity per electrode is also given as a feature of a stimulation procedure that preserves a low value of the size-intensity product.