Pixel lensing: Microlensing towards M31

Pixel lensing is gravitational microlensing of unresolved stars. The main target explored up to now has been the nearby galaxy of Andromeda, M31. The scientific issues of interest are the search for dark matter in form of compact halo objects, the study of the characteristics of the luminous lens and source populations and the possibility of detecting extra-solar (and extra-galactic) planets. In the present work we intend to give an updated overview of the observational status in this field.Comment: Invited article for the GRG special issue on gravitational lensing (Ph. Jetzer, Y. Mellier and V. Perlick Eds.

Information support and interactive planning in the digital factory : approach and industry-driven evaluation

In the modern world we are continuously surrounded by information. The human brain has to analyse and interpret this information to transform into useable knowledge that is then used in decision making activities. The advent and implementation of Industry 4.0 will make it a requirement for systems within factories to interact and share large quantities of information with each other. This large volume of information will make it even more difficult for the human resources within the factory to sift through the large amount of information required since there is a limit to the information that our brains can cope with. Just in time information retrieval (JITIR) within the digital factory environment aims to provide support to the human stakeholders in the system by proactively yet non-intrusively providing the required information at the right time based on the users context. This paper will therefore provide an insight into the cognitive difficulties experienced by humans in the digital factory and how JITIR can tackle these challenges. By validating the JITIR concept, several industry scenarios have been evaluated: an exemplary model, concerning the machine tool industry, is presented in the paper. The results of this research are a set of guidelines for the development of a digital factory support tool.peer-reviewe

Modeling of system knowledge for efficient agile manufacturing : tool evaluation, selection and implementation scenario in SMEs

In the manufacturing world, knowledge is fundamental in order to achieve effective and efficient real time decision making. In order to make manufacturing system knowledge available to the decision maker it has to be first captured and then modelled. Therefore tools that provide a suitable means for capturing and representation of manufacturing system knowledge are required in several types of industrial sectors and types of company’s (large, SME). A literature review about best practice for capturing requirements for simulation development and system knowledge modeling has been conducted. The aim of this study was to select the best tool for manufacturing system knowledge modelling in an open-source environment. In order to select this tool, different criteria were selected, based on which several tools were analyzed and rated. An exemplary use case was then developed using the selected tool, Systems Modeling Language (SysML). Therefore, the best practice has been studied, evaluated, selected and then applied to two industrial use cases by the use of a selected opens source tool.peer-reviewe

Mobile robot trajectory analysis with the help of vision system

© Springer Nature Switzerland AG 2019. We present a vision-based motion analysis method for single and multiple mobile robots which allows quantifying the robot's behaviour. The method defines how often and for how much each of the robots turn and move straight. The motion analysis relies on the robot trajectories acquired online or offline by an external camera and the algorithm is based on iteratively performed a linear regression to detect straight and curved paths for each robot. The method is experimentally validated with the indoor mobile robotic system. Potential applications include remote robot inspection, rescue robotics and multi-robotic system coordination

Reduction of current harmonics in grid-connected PV inverters using harmonic compensation - conforming to IEEE and IEC standards

This paper deals with the reduction of harmonics generated by Grid-Connected PV Inverters to conform to the harmonic limits set by the IEEE and IEC standards. An analysis of the current harmonics present in the output current of a grid-connected inverter will be presented. The inverter will be current controlled by a Proportional-Resonant (PR) current controller. The design and testing of the PR current controller will be presented. This paper will also deal with the application of harmonic compensation to make the inverter compliant to the standards, by using selective harmonic compensators in addition to the Proportional-Resonant (PR) controller. Both simulation and experimental results will be presented. Testing was carried out on a Grid-Connected PV Inverter which was designed and constructed for this research.peer-reviewe

Advanced experiential placements : challenges and opportunities for preceptors

The Doctorate in Pharmacy course offered by the University of Malta in collaboration with the University of Illinois, Chicago, offers six-week advanced experiential placements. Preceptors for the placement at Medicines Information guide international post-graduate doctorate students through an advanced clinical experiential education.peer-reviewe