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Satellite navigation systems are more and more used in geomatics. This penetration has not always taken into account the relative safety and security aspects and the consequent threats to the humans. This work focuses on these aspects that are often overlooked in geomatics. After a brief introduction on the evolution of satellite navigation systems and on future trends, the related safety and security risks are analyzed and possible countermeasures (Integrity, Awareness, and Protection) are discussed. [ABSTRACT FROM AUTHOR]

Multifunction radars based on active phased arrays are well known and widely studied systems. The concepts of bistatic architecture, conformal array and digital beam forming (DBF) are combined in this paper to define a novel multifunction radar for point defense. The conical shape of the antenna overcomes the significant limitations in the azimuth coverage of 360° of fixed-faces phased arrays due to the beam scanning up to 45°. The usage of separate transmit/receive arrays and the DBF technique adds the operational flexibility and the possibility of multiple simultaneous functions, with an optimal time-energy resources exploitation. After a short description of its technological demonstrator, some significant design trade-off, and operating aspects of the proposed architecture, called d-Radar, are described, showing the main differences with respect to the classical, four faces, and phased-array multifunction radar architecture. It is described how the operating modes can be made more and more similar to a “staring” or “ubiquitous” radar permitting an instantaneous detection and location of short-range, low-elevation targets for sea and ground operations. Finally, some remarks about the resources management and scheduling are shown with the results from a case of study. [ABSTRACT FROM PUBLISHER]

The article discusses an interpretation of the behavior of the apostle John and his dialog with Jesus at the Last Supper as depicted in the Gospel of John. It focuses on the unique situation of John as the beloved disciple and as the only one to be told the name of Jesus' traitor, Judas. According to the author this establishes an intimate bond between Jesus and John by which John comes to understand Jesus' love for Judas. The author reflects on the meaning of compassionate love and discipleship.

Radioastronomy and radiointerferometry operations below 20–30 MHz are severely hampered on the Earth surface by a number of reasons. The main two are the existence of the ionosphere acting as a rejecting filter for frequencies lower than about 20 MHz, and the presence in that spectral region of a strong electromagnetic pollution due to man-made activities (communications, broadcasting and radio frequency heating). Relevant advantages may be reached transferring those scientific investigations on the Moon and mostly on its “far side”. The paper presents these advantages and outlines some possible solutions. Three components are presented; the first one refers to the antenna and the antennae array to be realised on the hidden lunar surface. The second one deals with the receiver-transmitter to be deployed at each antenna with the needed synchronisation system since the phase must be preserved. The last one suggests some possible links needed to connect the lunar network to a data-collecting network, or to another interferometric station, space borne or on the Earth. The paper reflects the results of a thesis discussed at Politecnico di Torino. [ABSTRACT FROM AUTHOR]