Search results for "pattern"
showing 10 items of 4203 documents
Thermal modelling of the ATHENA X-IFU filters
2018
Copyright 2018 Society of Photo-Optical Instrumentation Engineers (SPIE). One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited. The X-IFU instrument of the ATHENA mission requires a set of thermal filters to reduce the photon shot noise onto its cryogenic detector and to protect it from molecular contamination. A set of five filters, operating at different nominal temperatures corresponding to the cryostat shield temperatures, is currently baselined. The knowledge of the actual filter temperature profi…
Radio frequency shielding of thin aluminized plastic filters investigated for the ATHENA X-IFU detector
2018
Copyright 2018 Society of Photo-Optical Instrumentation Engineers (SPIE). One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited. The X-ray Integral Field Unit (X-IFU) is one of the two detectors of the ATHENA astrophysics space mission approved by ESA in the Cosmic Vision 2015-2025 Science Programme. The X-IFU consists of a large array of transition edge sensors (TES) micro-calorimeters covering a field of view of 5' diameter, sensitive in the energy range 0.2-12 keV, and providing a spectral resolution…
The focal plane assembly for the Athena X-ray Integral Field Unit instrument
2016
This paper summarizes a preliminary design concept for the focal plane assembly of the X-ray Integral Field Unit on the Athena spacecraft, an imaging microcalorimeter that will enable high spectral resolution imaging and point-source spectroscopy. The instrument's sensor array will be a ~ 3840-pixel transition edge sensor (TES) microcalorimeter array, with a frequency domain multiplexed SQUID readout system allowing this large-format sensor array to be operated within the thermal constraints of the instrument's cryogenic system. A second TES detector will be operated in close proximity to the sensor array to detect cosmic rays and secondary particles passing through the sensor array for off…
Observation of instability of faceted crystals in lipid monolayers
1998
Abstract The morphological instabilities of two-dimensional hexagonal crystals in lipid monolayers are studied. Fluorescence microscopy indicates that beyond a critical size the faceted crystal develops into dendrites with unusual tip growth behavior, which is not consistent with the current theory of dendritic growth. The morphological transitions in relation to the driving force for two-dimensional crystal growth are also studied.
From witnessing to recording – material objects and the epistemic configuration of science classes
2012
Drawing on concepts developed in actor-network theory and postphenomenology this article shows how material objects in the science classroom become part of epistemic configurations and thus co-shape science education. An ethnographic study on epistemic objects in science education is the basis for the analysis of two of these objects: experimental arrangements and the blackboard. While experimental arrangements configure students as witnesses of the fascinating otherness of material objects, the blackboard enacts students as recorders of semiotic representations. In the interplay of these socio-material enactments scientific knowledge receives its authority in the classroom. The perspective…
Viajeros étnicos, gestos exóticos y encuentros esporádicos: los tours mayas en Los Altos de Chiapas
2018
Este trabajo reflexiona sobre la interacción turista/anfitrión en los tours étnicos promovidos en la región Altos Tsotsil-Tseltal Chiapas, México. Las agencias turísticas promueven diferentes encuentros de los turistas con la población indígena donde se espera que los primeros cumplan con sus expectativas sobre el Otro exótico y los segundos se acoplen a los imaginarios que corren sobre sí mismos. Aquí, al contrario, interesa analizar un espacio turístico en constante construcción con la observación de tres lugares de protagonismo indígena: un mercado indígena en San Cristóbal de Las Casas, una iglesia en San Juan Chamula y una casa de tejedoras en Zinacantán, donde los roles sociales del v…
Do networks matter? Network involvement and policy learning in Nordic regions
2017
ABSTRACTThe capacities of regions to form networks are an important feature of regional cooperation. This article assesses why Nordic regions engage in network activities and what new organizational patterns of collaboration emerge. It draws on historical data from a 2006–2008 survey of elected regional politicians from the Nordic countries. The article argues that through this process, participation in cross-border networks matters for regional learning as measured by the policy-choices of regions.
Designing a New Method of Studying Feature-Length Films
2019
Measuring viewers’ experiences of films has become a critical issue for filmmakers because all kinds of audiences now have access to new releases from all over the world. Some approaches have focused on the cognitive level of the experience, while others have emphasized the structure of films. Additionally, some have used quantitative objective methods to examine audience reactions to short film sequences, while others have applied qualitative approaches to study feature-length films. However, an integrated method that combines the features of these approaches is needed. In this article, we describe a new method that combines quantitative and qualitative data to study viewers’ experiences o…
The culture in the era of clutural capitlaism: Trends and Controversies
2014
[EN] This article offers a reflection on the way in which the evolution of capitalism towards a cultural capitalism phase is propitiating the emergence of a new regime of production and reception of cultural products. To approach this task it is examined one of the most clearly observable trends in the evolution that western societies have experienced in the past decades, that is, the transformation of the market in the general pattern of the social activities and the entrance of capitalist patterns in the cultural sphere. The article finishes with a critical analysis of the most frequently consequences attributed to the evolution of capitalism in the cultural domain: the degradation of the…
Study and Evaluation of Pre-trained CNN Networks for Cultural Heritage Image Classification
2021
The classification of digital images is an essential task during the restoration and preservation of cultural heritage (CH). In computer vision, cultural heritage classification relies on the classification of asset images regarding a certain task such as type, artist, genre, style identification, etc. CH classification is challenging as various CH asset images have similar colors, textures, and shapes. In this chapter, the aim is to study and evaluate the use of pre-trained deep convolutional neural networks such as VGG16, VGG-19, ResNet50, and Inception-V3 for cultural heritage images classification using transfer learning techniques. The main idea is to start with CNN models previously t…