Motor starting techniques for the 2 to 15 kW Brayton space power system

Motor starting techniques for 2-15 kW Brayton space power syste

fast indoor mapping to feed an indoor db for building and facility management

Abstract. Facility Management activities require to collect and organize a large amount of information about a building as, for example, geometry, MEP structures, lighting and antifire devices, typologies of furniture, paving characteristics, structures and more. Nowadays the data acquisition procedures for indoor environments are usually still carried on with old style approach, where surveyors have to manually map and acquire the data, walking along the sites with a poor level of digitalization The success story presented in the paper describes how using an Indoor Mobile Mapping approach (Zlot et al., 2014), it is possible to satisfy the need to acquire plant views of a large parts of buildings and, simultaneously, to record a 3D+Full resolution RGB images. Thanks to this fast acquisition it is later possible to feed a 2D/3D database, identifying the main objects needed to support a facility management process. The iMMS that has been used is based on SLAM approach, that allows the user to map and survey large sites also indoor, that means without the presence of GNSS signal and without the use of accurate and expense IMU devices. The data acquired in the field has been process with standard/commercial software that is usually used to create DB for outdoor mobile mapping.</p

Geometrical Description of Quantum Mechanics - Transformations and Dynamics

In this paper we review a proposed geometrical formulation of quantum mechanics. We argue that this geometrization makes available mathematical methods from classical mechanics to the quantum frame work. We apply this formulation to the study of separability and entanglement for states of composite quantum systems.Comment: 22 pages, to be published in Physica Script

Modification of magnetic and transport properties of manganite layers in Au/La_0.67Sr_0.33MnO_3/SrTiO_3 interfaces

The effect of gold capping on magnetic and transport properties of optimally doped manganite thin films is studied. An extraordinary suppression of conductivity and magnetic properties occurs in epitaxial (001) La_0.67Sr_0.33MnO_3 (LSMO) films grown on SrTiO_3 upon deposition of 2 nm of Au: in the case of ultrathin films of LSMO (4 nm thick) the resistivity increases by four orders of magnitude while the Curie temperature decreases by 180 K. Zero-field 55Mn nuclear magnetic resonance reveals a significant reduction of ferromagnetic double-exchange mechanism in manganite films upon the gold capping. We find evidence for the formation of a 1.9-nm thick magnetic "dead-layer" at the Au/LSMO interface, associated with the creation of interfacial non double-exchange insulating phases.Comment: 4 figure

Cu_{2}O as nonmagnetic semiconductor for spin transport in crystalline oxide electronics

We probe spin transport in Cu_{2}O by measuring spin valve effect in La_{0.7}Sr_{0.3}MnO_{3}/Cu_{2}O/Co and La_{0.7}Sr_{0.3}MnO_{3}/Cu_{2}O/La_{0.7}Sr_{0.3}MnO_{3} epitaxial heterostructures. In La_{0.7}Sr_{0.3}MnO_{3}/Cu_{2}O/Co systems we find that a fraction of out-of-equilibrium spin polarized carrier actually travel across the Cu_{2}O layer up to distances of almost 100 nm at low temperature. The corresponding spin diffusion length dspin is estimated around 40 nm. Furthermore, we find that the insertion of a SrTiO_{3} tunneling barrier does not improve spin injection, likely due to the matching of resistances at the interfaces. Our result on dspin may be likely improved, both in terms of Cu_{2}O crystalline quality and sub-micrometric morphology and in terms of device geometry, indicating that Cu_{2}O is a potential material for efficient spin transport in devices based on crystalline oxides.Comment: 15 pages, 10 figure

Using photo-elicitation to explore social representations of community multimedia centers in Mozambique.

Ten Mozambican Community Multimedia Centers (CMCs) were investigated by analyzing Social Representations of users and staff members. Photo-elicitation, an underexplored methodological approach in the domain of Information and Communication Technologies for Development (ICT4D), was employed to conduct the study, and a three-step qualitative content analysis was performed on both visual and textual data. Results tend to confirm and build upon outcomes from the existing literature on Public Access Venues (PAVs). Local communities value these centers because they bring social recognition to people working or learning there. The venues are associated with a symbolism that extends from the social recognition of the individual to the development and social inclusion of the whole community, which, because of the presence of the venue, does not feel left behind. In this vein, the study also shows that the importance of CMCs is often not related to the newest technology available, but to the technology that reaches the most of the community. The study also highlights neglected dimensions of CMCs, such as the importance of the exterior appearance of the venue, and the perception of a switch in their nature from static centers funded by third parties towards more entrepreneurial-driven ones. The presented research also contributes to the ICT4D field by proposing a promising research protocol, which is able to elicit representations otherwise difficult to obtain

Exploring the meanings of community multimedia centers in Mozambique : a social representations perspective

This article presents extensive research conducted in Mozambique that aims to deeply understand how different social groups understand community multimedia centers (CMCs), which are structures combining a community radio and a telecenter. The social representations theory was adopted to interpret narratives of 231 interviewees from 10 Mozambican provinces. Interviewees included representatives of initiating agencies, local staff members, CMC users (both the radio and telecenter components), users of only the community radio, and community members not using the CMCs. Following the analysis of transcribed interviews, six main clusters were identified, each of them shedding light on a specific understanding of a CMC. These are discussed according to a set of sociodemographic variables. This study suggests that the social representations theory is a valuable framework to provide an integrated view of ICT4D interventions by giving a voice to local perspectives without overlooking the initiating agencies’ expectations

Exploring the meanings of community multimedia centers in Mozambique: a social representation perspective

This article presents extensive research conducted in Mozambique that aims to deeply understand how different social groups understand community multimedia centers (CMCs), which are structures combining a community radio and a telecenter. The social representations theory was adopted to interpret narratives of 231 interviewees from 10 Mozambican provinces. Interviewees included representatives of initiating agencies, local staff members, CMC users (both the radio and telecenter components), users of only the community radio, and community members not using the CMCs. Following the analysis of transcribed interviews, six main clusters were identified, each of them shedding light on a specific understanding of a CMC. These are discussed according to a set of sociodemographic variables. This study suggests that the social representations theory is a valuable framework to provide an integrated view of ICT4D interventions by giving a voice to local perspectives without overlooking the initiating agencies' expectations