The radio spectra of reddened 2MASS QSOs: evidence for young radio jets

Multifrequency radio continuum observations (1.4-22 GHz) of a sample of reddened QSOs are presented. We find a high incidence (13/16) of radio spectral properties, such as low frequency turnovers, high frequency spectral breaks or steep power-law slopes, similar to those observed in powerful compact steep spectrum (CSS) and gigahertz-peaked spectrum (GPS) sources. The radio data are consistent with relatively young radio jets with synchotron ages <1e6-1e7yr. This calculation is limited by the lack of high resolution (milli-arcsec) radio observations. For the one source in the sample that such data are available a much younger radio age is determined, <2e3yr, similar to those of GPS/CSS sources. These findings are consistent with claims that reddened QSOs are young systems captured at the first stages of the growth of their supermassive black holes. It also suggests that expanding radio lobes may be an important feedback mode at the early stages of the evolution of AGN.Comment: 9 pages, to appear in MNRA

The Phoenix Deep Survey: The 1.4 GHz microJansky catalogue

The initial Phoenix Deep Survey (PDS) observations with the Australia Telescope Compact Array have been supplemented by additional 1.4 GHz observations over the past few years. Here we present details of the construction of a new mosaic image covering an area of 4.56 square degrees, an investigation of the reliability of the source measurements, and the 1.4 GHz source counts for the compiled radio catalogue. The mosaic achieves a 1-sigma rms noise of 12 microJy at its most sensitive, and a homogeneous radio-selected catalogue of over 2000 sources reaching flux densities as faint as 60 microJy has been compiled. The source parameter measurements are found to be consistent with the expected uncertainties from the image noise levels and the Gaussian source fitting procedure. A radio-selected sample avoids the complications of obscuration associated with optically-selected samples, and by utilising complementary PDS observations including multicolour optical, near-infrared and spectroscopic data, this radio catalogue will be used in a detailed investigation of the evolution in star-formation spanning the redshift range 0 < z < 1. The homogeneity of the catalogue ensures a consistent picture of galaxy evolution can be developed over the full cosmologically significant redshift range of interest. The 1.4 GHz mosaic image and the source catalogue are available on the web at http://www.atnf.csiro.au/~ahopkins/phoenix/ or from the authors by request.Comment: 16 pages, 11 figures, 4 tables. Accepted for publication by A

Observation of Microlensing towards the Galactic Spiral Arms. EROS II 2 year survey

We present the analysis of the light curves of 8.5 million stars observed during two seasons by EROS (Experience de Recherche d'Objets Sombres), in the galactic plane away from the bulge. Three stars have been found that exhibit luminosity variations compatible with gravitational microlensing effects due to unseen objects. The corresponding optical depth, averaged over four directions, is 0.38 (+0.53, -0.15) 10^{-6}. All three candidates have long Einstein radius crossing times ($\sim$ 70 to 100 days). For one of them, the lack of evidence for a parallax or a source size effect enabled us to constrain the lens-source % geometric configuration. Another candidate displays a modulation of the magnification, which is compatible with the lensing of a binary source. The interpretation of the optical depths inferred from these observations is hindered by the imperfect knowledge of the distance to the target stars. Our measurements are compatible with expectations from simple galactic models under reasonable assumptions on the target distances.Comment: 11 pages, 13 figures, accepted by A&A in Aug 9

An energy management platform for public buildings

This paper describes the development and implementation of an electronic platform for energy management in public buildings. The developed platform prototype is based on the installation of a network of wireless sensors using the emerging Long Range (LoRa) low power long-range wireless network technology. This network is used to collect sensor data, which is stored online and manipulated to extract knowledge and generate actions toward energy saving solutions. In this process, gamification approaches were used to motivate changes in the users' behavior towards more sustainable actions in public buildings. These actions and the associated processes can be implemented as public services, and they can be replicated to different public buildings, contributing to a more energy-sustainable world. The developed platform allows the monitoring and management of the heating/cooling, electric power consumption, and lighting levels. In order to validate the proposed electronic platform, sensor information was collected in the context of a university campus, which was used as an application scenario in public buildings.info:eu-repo/semantics/publishedVersio

An Android-based personalized public transportation advisor

This work presents the development of a mobile application which allows the user to access real time data related with public transportation information. This application combines the geographic user context and preferences with the data provided by a public transportation information system, fulfilling the necessities of today’s passengers and providing an incentive for the population to use the public transportation infrastructure. The proposed application, still in prototype stage, allows the user to benefit from real time access to public transportation data in a simple and intuitive form. Results from use cases and real world tests using data from a Brazilian bus fleet operator were employed to validate the operability and features of the developed prototype.info:eu-repo/semantics/acceptedVersio

Dynamics of fast pattern formation in porous silicon by laser interference

Patterns are fabricated on 290 nm thick nanostructured porous silicon layers by phase-mask laser interference using single pulses of an excimer laser (193 nm, 20 ns pulse duration). The dynamics of pattern formation is studied by measuring in real time the intensity of the diffraction orders 0 and 1 at 633 nm. The results show that a transient pattern is formed upon melting at intensity maxima sites within a time 1-µs) upon melting induced by homogeneous beam exposure and related to the different scenario for releasing the heat from hot regions. The diffraction efficiency of the pattern is finally controlled by a combination of laser fluence and initial thickness of the nanostructured porous silicon layer and the present results open perspectives on heat release management upon laser exposure as well as have potential for alternative routes for switching applications.Postprint (published version

IoT and blockchain paradigms for EV charging system

In this research work, we apply the Internet of Things (IoT) paradigm with a decentralized blockchain approach to handle the electric vehicle (EV) charging process in shared spaces, such as condominiums. A mobile app handles the user authentication mechanism to initiate the EV charging process, where a set of sensors are used for measuring energy consumption, and based on a microcontroller, establish data communication with the mobile app. A blockchain handles financial transitions, and this approach can be replicated to other EV charging scenarios, such as public charging systems in a city, where the mobile device provides an authentication mechanism. A user interface was developed to visualize transactions, gather users’ preferences, and handle power charging limitations due to the usage of a shared infrastructure. The developed approach was tested in a shared space with three EVs using a charging infrastructure for a period of 3.5 months.info:eu-repo/semantics/publishedVersio