Search results for "Planetary Science"

Towards a Dual-mode Adaptive MAC Protocol (DMA-MAC) for Feedback-based Networked Control Systems

2014

Abstract Automated control systems play an important part in many industrial domains and the medium used for communication between devices in these systems is in transition from wired to wireless for cost reasons. Control systems have strict requirements on delay, throughput, and reliability, that vary with time during operation. Addressing these requirements requires predictable and robust protocols to be employed, and they must be adaptive to the varying states of the controlled process. In this article, we propose a dual-mode adaptive medium access control protocol that caters for two main operation modes in control systems: the steady mode operation, and the transient mode operation. We…

Understanding the Impact of Trampling on Rodent Bones

2022

Experiments based on the premise of uniformitarism are an effective tool to establish patterns of taphonomic processes acting either before, or after, burial. One process that has been extensively investigated experimentally is the impact of trampling to large mammal bones. Since trampling marks caused by sedimentary friction strongly mimic cut marks made by humans using stone tools during butchery, distinguishing the origin of such modifications is especially relevant to the study of human evolution. In contrast, damage resulting from trampling on small mammal fossil bones has received less attention, despite the fact that it may solve interesting problems relating to site formation proces…

Reforma jurídico-administrativa, procedimiento electrónico y Administración local: análisis de la incidencia de las recientes transformaciones en las…

2020

Este trabajo aspira a identificar los elementos y rasgos del funcionamiento del procedimiento administrativo español que, en su conformación actual tras las reformas de los últimos años y especialmente tras las reformas de 2015, más han afectado al funcionamiento de las administraciones locales. En concreto, se identificarán aquellos elementos que, a pesar de haberse operado una reforma, son en el fondo manifestación de una clara continuidad con el modelo tradicional y ya consolidado, por un lado, así como, por otro, cuáles son las novedades más importantes efectivamente operadas con la reforma. Adicionalmente, se pretende explicar cómo se relacionan estas transformaciones con otros cambios…

Modeling an X-ray Flare on Proxima Centauri: evidence of two flaring loop components and of two heating mechanisms at work

2003

We model in detail a flare observed on Proxima Centauri with the EPIC-PN on board XMM-Newton at high statistics and high time resolution and coverage. Time-dependent hydrodynamic loop modeling is used to describe the rise and peak of the light curve, and a large fraction of the decay, including its change of slope and a secondary maximum, over a duration of more than 2 hours. The light curve, the emission measure and the temperature derived from the data allow us to constrain the loop morphology and the heating function and to show that this flare can be described with two components: a major one triggered by an intense heat pulse injected in a single flaring loop with half-length ~1.0 10^{…

Contribution of mode coupling and phase-mixing of Alfv\'en waves to coronal heating

2017

This research has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 647214) and from the UK Science and Technology Facilities Council. This work used the DiRAC Data Centric system at Durham University, operated by the Institute for Computational Cosmology on behalf of the STFC DiRAC HPC Facility (www.dirac.ac.uk. This equipment was funded by a BIS National E-infrastructure capital grant ST/K00042X/1, STFC capital grant ST/K00087X/1, DiRAC Operations grant ST/K003267/1 and Durham University. Context. Phase-mixing of Alfvén waves in the solar corona has been identified as one possible candid…

Competitive firms in thin regions in Norway: The importance of workplace learning

2015

The article departs from empirical studies of two competitive firms in an organisationally thin region in Norway. The main question in the article is how these firms have achieved global competitiveness. The article focuses its inquiry on how the firms organise their innovation activity, giving special attention to the firms' organisational learning and absorptive capacity. It is found that find that workplace learning enables the firms to utilise knowledge in uncommon ways. The learning rests on specific organisational traits in the firms, such as broad participation, long-term on-the-job training, the use of practice-based knowledge in innovation projects, and links to national and global…

“Nice to get to know you”

2020

Virtual exchange comprises online collaborative activities in facilitated, educational contexts across borders. This paper offers a multimodal approach to the study of social presence in students’ asynchronous online discourse in the context of virtual exchange. It draws on the Community of Inquiry model of online learning (Garrison 2017) and interprets social presence as the dynamic discursive process of social interaction and self-presentation. The data consists of screenshots collected in a closed Facebook group during the first assignment of a Czech-Finnish virtual exchange project in 2017. The study aims to explore how the method of multimodal discourse analysis can be used to describe…

Hypertext'99 doctoral consortium report

1999

How was the Turin Shroud Man crucified?

2014

As the literature is not exhaustive with reference to the way the Turin Shroud (TS) Man was crucified, and it is not easy to draw significant information from only a "photograph" of a man on a linen sheet, this study tries to add some detail on this issue based on both image processing of high resolution photos of the TS and on experimental tests on arms and legs of human cadavers. With regard to the TS Man hands, a first hypothesis states that the left hand of the TS Man was nailed twice at two different anatomical sites: the midcarpal joint medially to the pisiform between the lunate/pyramidal and capitate/uncinate bones (Destot's space) and the radiocarpal joint between the radio, lunate…

The Athena X-ray Integral Field Unit: a consolidated design for the system requirement review of the preliminary definition phase

2023

The Athena X-ray Integral Unit (X-IFU) is the high resolution X-ray spectrometer, studied since 2015 for flying in the mid-30s on the Athena space X-ray Observatory, a versatile observatory designed to address the Hot and Energetic Universe science theme, selected in November 2013 by the Survey Science Committee. Based on a large format array of Transition Edge Sensors (TES), it aims to provide spatially resolved X-ray spectroscopy, with a spectral resolution of 2.5 eV (up to 7 keV) over an hexagonal field of view of 5 arc minutes (equivalent diameter). The X-IFU entered its System Requirement Review (SRR) in June 2022, at about the same time when ESA called for an overall X-IFU redesign (i…