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This paper presents several demonstrators that utilize advanced additive manufacturing (AM) to rapidly prototype antennas, RF components for microwave and mm-wave applications. Antenna substrates with tailored permittivity; lenses, reflectarray with locally varied dielectric properties; and metamaterials can be fabricated by using extrusion based AM processes such as fused filament fabrication method to realize high gain antenna systems with low material cost, time-saving and low impact to the environment.

In this paper we discuss the integration of a communication model in the MOBOT assistive robotic platform and its evaluation by target users. The MOBOT platform envisions the development of cognitive robotic assistant prototypes that act proactively, adaptively and interactively with respect to elderly humans with slight walking and cognitive impairments. The respective multimodal action recognition system has been developed to monitor, analyze and predict user actions with a high level of accuracy and detail. The robotic platform incorporates a human-robot communication model that has been defined with semantics of human actions in interaction, their capture and their representation in terms of behavioral patterns, to achieve an effective, natural interaction, aiming to support elderly users of slight walking and cognitive inability. The platform has been evaluated in a series of validation experiments with end users, the procedure and results of which are also presented in this paper.

The Fluorescence Explorer (FLEX) mission has been recently selected as the 8th Earth Explorer by the European Space Agency (ESA). It will be the first mission specifically designed to measure from space vegetation fluorescence emission, by making use of very high spectral resolution imaging spectroscopy techniques. Vegetation fluorescence is the best proxy to actual vegetation photosynthesis which can be measurable from space, allowing an improved quantification of vegetation carbon assimilation and vegetation stress conditions, thus having key relevance for global mapping of ecosystems dynamics and aspects related with agricultural production and food security. The FLEX mission carries the FLORIS spectrometer, with a spectral resolution in the range of 0.3 nm, and is designed to fly in tandem with Copernicus Sentinel-3, in order to provide all the necessary spectral / angular information to disentangle emitted fluorescence from reflected radiance, and to allow proper interpretation of the observed fluorescence spatial and temporal dynamics.

This paper reports on work related to the modelling of Human-Robot Communication on the basis of multimodal and multisensory human behaviour analysis. A primary focus in this framework of analysis is the definition of semantics of human actions, i.e. verbal and non-verbal signals, in a specific context with distinct Human-Robot interaction states. These states are captured and represented in terms of communicative behavioural patterns that influence, and in turn are adapted to the interaction flow with the goal to feed a multimodal human-robot communication system. This multimodal HRI model is defined upon, and ensures the usability of a multimodal sensory corpus acquired as a primary source of data retrieval, analysis and testing of mobility assistive robot prototypes.

In an age, of accelerating challenges, towards a new digital era of cultural heritage dissemination, the convergence of information and telecommunication technologies have given us significant advantages in promoting the cultural content in all over the world. It is quite clear that we are facing a real challenge of capturing one or several methods in designing and developing new ways of improving real or web visitor's experience in archeological and other cultural interesting areas. By this point of view, this paper proposes a new interactive approach, in real-presence viewing, recording and analyzing the live interaction between people and cultural exhibits, artifacts or other intellectual creations by combining WiFi-RFID technologies and data mining techniques, called Eye-View.

Previous work in the framework of the MOBOT European project has led to acquisition of a multimodal sensory corpus that is intended to become the primary source of data retrieval, data analysis and testing of the mobility assistive robot prototypes currently under development within the project. The rich and multi-layered annotation of this corpus is a key factor for the usability of the acquired dataset. To this end, in this paper we report on the definition of the adopted annotation scheme, focusing on annotation tiers applied to audio-gestural signals intended to provide the ground truth dataset for the training and evaluation of visual and audio recognition algorithms, and also form the basis for the definition of the project's multimodal human-robot communication model.

The continuous increase of illegal migration flows to southern European countries has been recently in the spotlight of European Union due to numerous deadly incidents. Another common issue that the aforementioned countries share is the Mediterranean wildfires which are becoming more frequent due to the warming climate and increasing magnitudes of droughts. Different ground early warning systems have been funded and developed across these countries separately for these incidents, however they have been proved insufficient mainly because of the limited surveyed areas and challenging Mediterranean shoreline and landscape. In 2011, the Greek Government along with European Commission, decided to support the development of the first Hellenic Civil Unmanned Aerial Vehicle (HCUAV), which will provide solutions to both illegal migration and wildfires. This paper presents the challenges in the electronics and software design, and especially the under development solutions for detection of human and fire activity, image mosaicking and orthorectification using commercial off-the-shelf sensors. Preliminary experimental results of the HCUAV medium altitude remote sensing algorithms, show accurate and adequate results using low cost sensors and electronic devices.

In this paper we deal with the problem of finding more effective ways of asking questions to a user gathering personalised information which will allow for an effective profiling regarding the educational various aspects of its navigation. Our aim is to discover new ways of filling questionnaires by web users, using intelligent information gathering system (IIGS) in relation to the dissemination of cultural content. Our approach is two folded, on one set we have to develop new “questioning techniques”, which will increase response rates, and on the other side use the most appropriate analytical methods in measuring effectiveness of a questioning technique and methods of comparing various technique.

Under sun-light illumination, the shape of the atmospheric oxygen bands (O 2 -B, 687 nm and O 2 -A, 760 nm) of the vegetation radiance is modified by chlorophyll fluorescence. However for far-range measurements, atmospheric effects also modify this shape. In this study, measurements in O 2 -A and O 2 -B absorption bands have been performed at different altitudes up to 3123 m over bare soil and wheat fields. It is observed that bands depth increase significantly with altitude. In O 2 -B band, the total magnitude of variation is of the same order of magnitude as the change induced by vegetation fluorescence, while it is much greater in O 2 -A band. We used MODTRAN 4 to correct measurements from these atmospheric effects and to retrieve ground level band depths. It is found that the variation of corrected band depth with altitude is greatly reduced. These results show that MODTRAN 4 can be used to account for atmospheric effects. We also showed that an accurate evaluation of the contribution of environment is needed to correct band depth from atmospheric effects, especially in the O 2 -B band.

There is an increasing need for automatic tools and techniques for application parallelization. Within the ALMA toolset, programs written in Scilab are automatically parallelized for execution on embedded multicore platforms. In this paper, key parts of the coarse grain parallelism optimization are presented. The coarse grain parallelism optimization considers the hierarchical task graph of a program and produces an optimized parallel schedule.

Today's reconfigurable multicore architectures become more and more complex. They consist of several processing units, not necessarily identical, different interconnecting modules, memories and possibly other components. Programming such kind of architectures requires deep knowledge of the underlying hardware and is thus very time consuming and error prone. On the other hand, automated tool chains that target multicore architectures are typically tailored to one specific architecture type and require a platform-specific programming model. Within the EU FP7 project Architecture oriented paraLlelization for high performance embedded Multicore systems using scilAb (ALMA) we address this shortcoming by a flexible tool chain featuring platform-independence on the architecture level as well as on the programming model. Thus, the tool chain is kept retarget able by using a novel architecture description language (ADL) for multiprocessor system on chip devices. Applications are expressed using the Scilab programming language allowing the end user to develop optimized programs without specific knowledge of the target architectures. Thereby, the ADL guides the code generation of the integrated tool flow through coarse- and fine grain parallelism extraction, parallel code optimizations and multicore simulations.

Examination timetabling for universities is a difficult optimization problem with its main objective being to produce the best possible schedule for every student participating. Metaheuristics are a common way of coping with this problem mainly due to their flexibility in adapting to complex real world situations. In this contribution, Grid resources are exploited in order to locate solutions that might have been unreachable in a reasonable time using the processing power of a single computer.

This paper describes the ERMIS system, specially designed to support the fleet and personnel scheduling and management issues, as well as to support various business collaboration issues for a helicopter taxi company. The implemented system offers a web-based interface for the flying and stationary personnel and a software application running on a PDA with GSM and GPS capabilities for the pilots. The information flow and the business processes of the ERMIS system are based on XML Web Services which makes the system open and interoperable with other company-owned information systems.

This paper describes the architecture and design evolution of an application-specific service platform following the Web services and grid related developments. The adoption of Web services standards for the various components of a scheduling service provider named SchedSP-WS is the main contribution of this paper. The use of grid standards for the seamless integration of the service provider and the computational infrastructure is also presented

Time-resolved measurements of the laser-induced chlorophyll fluorescence emission of vegetation detected by two different techniques are described. Fluorescence decay time measurements using single photon counting and picosecond laser pulse excitation have been used to analyze the fluorescence heterogeneity of plant leaves. The fluorescence is described by lifetimes of 10-40, 80-150, 400-500, and 700-1000 ps. By closing the reaction centers via application of the herbicide DCMU, the lifetimes of the two slowest components increase by a factor of about three. Another possible method to monitor the fluorescence after picosecond excitation could be a streak camera detection system. Measurements performed on the slow decay component of stressed and unstressed plants are presented. >

Remote sensing of photosynthesis by fluorosensing and related techniques is a complementary approach to gas exchange and circulation models that helps to monitor accurately the spatial and temporal changes in biosphere primary production. Although important advances have been made in the fields of fluorosensing during the past ten years, a comprehensive review of the different techniques available and their scope is lacking. The aim of the present review is to examine the emerging techniques in order to evaluate their potential for application at different integration levels, from leaf canopy, and from ground measurements to satellite detection. It is also intended to highlight the actual limitations and the necessary preparatory steps towards a space mission. Finally, the information that could be obtained from satellite measurements will be reviewed.