Search results for "Space."
showing 10 items of 21534 documents
Decoupled control scheme of grid-connected split-source inverters
2017
Grid-connected power conversion systems for renewable energy sources must fulfill several requirements, e.g., the high efficiency, the reduced cost and complexity, and, quite often, the boost capabilities that is usually achieved using a front-end dc–dc boost converter before the inversion stage, leading to a two-stage architecture. Meanwhile, single-stage power conversion systems, which perform the boosting operation within the inversion one, offer some potential advantages, in terms of reducing the complexity and the volume of the whole system. Among several proposed options, the split-source inverter (SSI) has been recently proposed by Abdelhakim et al. as an alternative option with some…
Relationship between volume and energy of vector fields
2001
Abstract A unified study of energy and volume functionals is presented here by determining the critical points of a functional that extends simultaneously energy and volume and that is defined on the product of the manifold of smooth maps C∞(M,N) times the manifold M of riemannian metrics on M. The restriction of this functional to different submanifolds of the space of vector fields X (M)× M is also considered, and used to study several functionals generalizing volume and energy or total bending of vector fields
Cybersecurity Attacks on Software Logic and Error Handling Within ADS-B Implementations: Systematic Testing of Resilience and Countermeasures
2022
Automatic Dependent Surveillance-Broadcast (ADS-B) is a cornerstone of the next-generation digital sky and is now mandated in several countries. However, there have been many reports of serious security vulnerabilities in the ADS-B architecture. In this paper, we demonstrate and evaluate the impact of multiple cyberattacks on ADS-B via remote radio frequency links that affected various network, processing, and display subsystems used within the ADS-B ecosystem. Overall we implemented and tested 12 cyberattacks on ADS-B in a controlled environment, out of which 5 attacks were presented or implemented for the first time. For all these attacks, we developed a unique testbed that consisted of 1…
Behavioural, ecological, and evolutionary aspects of diversity in frog colour patterns
2017
The role of colours and colour patterns in behavioural ecology has been extensively studied in a variety of contexts and taxa, while almost overlooked in many others. For decades anurans have been the focus of research on acoustic signalling due to the prominence of vocalisations in their communication. Much less attention has been paid to the enormous diversity of colours, colour patterns, and other types of putative visual signals exhibited by frogs. With the exception of some anecdotal observations and studies, the link between colour patterns and the behavioural and evolutionary ecology of anurans had not been addressed until approximately two decades ago. Since then, there has been eve…
From ‘no dogs here!’ to ‘beware of the dog!’ : restricting dog signs as a reflection of social norms
2019
Signs in public space reflect ‘normalcy’ in a community. The authors ask what restricting signs tell us about a society? In order to explore the system and variation in the ways dog signs manifest different norms and control, they compare two different data sets: dog signs in a Northern European town, Jyväskylä in Finland, and two Eastern European villages in Romania. They apply a qualitative methodology based on visual communication, geosemiotics and linguistic landscape studies. The focus of the article is on the resources of addressing and the visual semiotics of the image. The investigated communities seem to create a complementary distribution of what they regulate that is also displa…
Una más de la familia. Au pairs atrapadas entre el capital humano y la economía moral
2018
In contemporary societies we are witnessing an expansion of the messages of human capital. These messages have as their central dimension idea of the self-entrepreneur, which implies a deepening in the logic of activation, while blurring the wage relations. In this scenario, young people with university degrees are becoming a favourite target in the offensive of human capital. The penetration of these human capital messages can be seen in the discourses of young university students who have been forced to leave the country during the crisis. In the present text we approach the discourses of young women who came out as au pairs. The characteristics of this figure place it in a space halfway …
MR2541232 (2010j:60101) Yong, Jiao; Lihua, Peng; Peide, Liu Atomic decompositions of Lorentz martingale spaces and applications. J. Funct. Spaces App…
2010
In this paper atomic decomposition theorems of martingales are considered. In particular, three atomic decomposition theorems for Lorentz martingale spacesHs p,q, Qp,q andDp,q, where 0 < p < 1, and 0 < q 1, are proved. As a consequence of these decompositions, the authors obtain a sufficient condition for a sublinear operator T, defined on the previous Lorentz martingale spaces Hs p,q, Qp,q and Dp,q and taking values in Lorentz spaces Lr, to be bounded. Also, a restricted weak-type interpolation theorem is established.
Los paisajes de la globalización, la elección de la ciudad-expo 2008. ¿Qué pasa con la gobernanza urbana frente a las estrategias económicas y espaci…
2005
Am 16. Dezember 2004 wählte das Bureau international des expositions (B.I.E.) Spanien und seine Kandidatenstadt, die Metropole Saragossa, als Organisationsland für die nächste internationale Ausstellung „International Exhibition of Zaragoza Spain 2008: Water and Sustainable Development“. Wir analysieren zunächst die Entwicklung "der Wege" der Kandidaturen zur Wahl der Gastgeberstadt der Internationalen Ausstellung 2008, dann greifen wir in einem zweiten Mal den gesamten Vorgang der Ausarbeitung, Begründung und Durchführung der Internationalen Ausstellung 2008 in Saragossa auf im Kontext der Globalisierung neue städtische Formen und Formen des Regierens hervorbringen, indem alle finanziellen…
Search for inelastic scattering of WIMP dark matter in XENON1T
2021
We report the results of a search for the inelastic scattering of weakly interacting massive particles (WIMPs) in the XENON1T dark matter experiment. Scattering off $^{129}$Xe is the most sensitive probe of inelastic WIMP interactions, with a signature of a 39.6 keV de-excitation photon detected simultaneously with the nuclear recoil. Using an exposure of 0.89 tonne-years, we find no evidence of inelastic WIMP scattering with a significance of more than 2$\sigma$. A profile-likelihood ratio analysis is used to set upper limits on the cross-section of WIMP-nucleus interactions. We exclude new parameter space for WIMPs heavier than 100 GeV/c${}^2$, with the strongest upper limit of $3.3 \time…
3D Visualization of Engendering Collaborative Leadership in the Space
2011
The paper focuses on collaborative leadership in education and how to illustrate its engendering process in a three-dimensional space. This complex and fluid process is examined as distributed and pedagogical within a large Finnish vocational upper secondary educational organization. As a consequence, the notion of distributed pedagogical leadership is used when collaborative leadership in education is studied. Collaborative leadership is argued to consist of the innermost substance of a professional learning community, as characteristics or qualities of a group of people working together for specific purposes. Therefore, collaborative leadership naturally involves actors, activities, and c…