Preservation of villages constructed on sliding areas - a case study from Karditsa Prefecture, Greece

Εντός των ορίων της Ελληνικής επικράτειας εντοπίζονται πολυάριθμα χωριά τα οποία εγκαταλείφθηκαν εξαιτίας του γεγονότος ότι είχαν θεμελιωθεί σε περιοχές που πλήττονταν από κατολισθήσεις. Πολλά από τα χωριά αυτά στις μέρες μας ανακατασκευάζονται προκειμένου να χρησιμοποιηθούν για εξοχικές κατοικίες. Η επιλογή των μέτρων προστασίας για την αντιμετώπιση των επιμέρους γεωτεχνικών προβλημάτων που προκαλούν οι κατολισθήσεις πρέπει να βασίζεται στις αρχές της ορθολογικής διαχείρισης των οικονομικών πόρων. Δηλαδή η κατασκευή ακριβών μέτρων υποστήριξης για την προστασία εγκαταλελειμμένων κατοικιών ή οικοπέδων ασήμαντης οικονομικής αξίας δεν είναι αποδεκτή. Στις περιπτώσεις ανακατασκευής τέτοιων χωριών πρέπει απαραιτήτως να προηγείται μελέτη γεωλογικής καταλληλότητας. Η συγκεκριμένη μελέτη μπορεί να εντοπίσει τις ασταθείς περιοχές και να υποδείξει τρόπους ανακατασκευής που να αποτρέπουν την επαναενεργοποίηση των κατολισθήσεων ή εφόσον επαναενεργοποιηθούν να αποτρέπουν την πρόκληση φθορών σε κατοικίες. Επιπλέον, η συγκεκριμένη μελέτη μπορεί να υποδείξει συνδυασμούς μέτρων ικανών να αναστείλουν τη δράση των παραγόντων που προκαλούν τα κατολισθητικά φαινόμενα με το μικρότερο δυνατό κόστος. Το Πετροχώρι της κοινότητας Αργιθέας του Νομού Καρδίτσας αποτελεί ένα τυπικό παράδειγμα ανακατασκεύαζα μενού χωριού το οποίο αντιμετωπίζει σοβαρά γεωτεχνικά προβλήματα λόγω των κατολισθητικών φαινομένων που πλήττουν ένα μεγάλο τμήμα του. Ο συνδυασμός των ήπιων και οικονομικών μέτρων προστασίας που προτείνονται για την αντιμετώπιση των προβλημάτων αυτών μπορεί να αποτελέσει αναφορά για ανάλογες περιπτώσεις περιστασιακώς κατοικίσημων χωριώνThe mountainous areas of the Greek dominion are occupied by many occasionally inhabitable villages that were deserted because of the fact that they were founded on areas affected by landslides. Many of those villages, during the last years, were reconstructed and their houses were turned into occasionally inhabitable country houses. The proposed support and protection measures for the reconstruction of those villages must follow the rules of the rational management of the financial sources. The construction of expensive retaining structures in order to protect deserted houses or building sites of insignificant value is inexcusable. In those cases the geological studies must precede all reconstruction activities. Those studies can provide detailed guide-lines in order to prevent the reactivation of the landslides and/or to reduce the implications in case of reactivation. Also, the geological studies can determine the necessary combination of the protection and support measures capable to block the preparatory and the triggering causal factors of the sliding movements. This way, the cost of the applied measures reduces to acceptable levels, compatible to the occasional use of those villages. Petroxori village (Argithea district, Karditsa prefecture) is a typical example of a village constructed on an unstable area that generated several geotechnical problems. The evaluation of those problems and the presentation of the proposed measures can be a useful reference for the confrontation of similar situation

Mooring chain climbing robot for NDT inspection applications

Inspection of mooring chains is an important but dangerous and costly procedure covering inspection above and below the waterline. The paper presents initial results from the RIMCAW project which aimed at designing and building an inspection robot able to climb mooring chains and deploy NDT technologies for scanning individual links thereby detecting critical defects. The paper focuses on the design and realisation of the inchworm type novel crawler developed and tested in the TWI Middlesbrough, UK water tank

A Novel Holonomic Mobile Manipulator Robot For Construction Sites

This article describes a novel mobile manipulator robot designed to work at height on construction sites. The robot comprises a mobile platform and a scissor lifter on which an ABB 6 dof manipulator is mounted. The mobile base is characterised by holonomic kinematics, provided by a novel designed omnidirectional wheel system that can travel directly and autonomously to desired poses. The robot was successfully tested in a construction site scenario to perform drilling tasks

A Search for Technosignatures Around 11,680 Stars with the Green Bank Telescope at 1.15-1.73 GHz

We conducted a search for narrowband radio signals over four observing sessions in 2020-2023 with the L-band receiver (1.15-1.73 GHz) of the 100 m diameter Green Bank Telescope. We pointed the telescope in the directions of 62 TESS Objects of Interest, capturing radio emissions from a total of ~11,680 stars and planetary systems in the ~9 arcminute beam of the telescope. All detections were either automatically rejected or visually inspected and confirmed to be of anthropogenic nature. In this work, we also quantified the end-to-end efficiency of radio SETI pipelines with a signal injection and recovery analysis. The UCLA SETI pipeline recovers 94.0% of the injected signals over the usable frequency range of the receiver and 98.7% of the injections when regions of dense RFI are excluded. In another pipeline that uses incoherent sums of 51 consecutive spectra, the recovery rate is ~15 times smaller at ~6%. The pipeline efficiency affects calculations of transmitter prevalence and SETI search volume. Accordingly, we developed an improved Drake Figure of Merit and a formalism to place upper limits on transmitter prevalence that take the pipeline efficiency and transmitter duty cycle into account. Based on our observations, we can state at the 95% confidence level that fewer than 6.6% of stars within 100 pc host a transmitter that is detectable in our search (EIRP > 1e13 W). For stars within 20,000 ly, the fraction of stars with detectable transmitters (EIRP > 5e16 W) is at most 3e-4. Finally, we showed that the UCLA SETI pipeline natively detects the signals detected with AI techniques by Ma et al. (2023).Comment: 22 pages, 9 figures, submitted to AJ, revise

COVERED INTEREST PARITY AND THE EFFICIENCY OF THE AUSTRALIAN DOLLAR FORWARD MARKET: A COINTEGRATION ANALYSIS USING DAILY DATA

This paper examines covered interest parity and speculative efficiency using cointegration techniques on a daily data set for Australian dollar/US dollar spot and forward rates and Australian and US interest rates. Cointegreation between the forward premium and the interest rate differential in both the 3 month and 6 month markets establishes covered interest parity as a possible long run equilibrium relationship for the sample period. However, both a well defined EC mechanism and the fact that past changes in the interest rate differential help predict the forward premium suggest the markets did not utilise all available information efficiently. Neither the 3 month not he 6 month forward rate cointegrate with the spot rate implying that these variables may have drifted apart over the sample period. Speculative efficiency may be rejected for these markets

COVERED INTEREST PARITY AND THE EFFICIENCY OF THE AUSTRALIAN DOLLAR FORWARD MARKET: A COINTEGRATION ANALYSIS USING DAILY DATA

This paper examines covered interest parity and speculative efficiency using cointegration techniques on a daily data set for Australian dollar/US dollar spot and forward rates and Australian and US interest rates. Cointegreation between the forward premium and the interest rate differential in both the 3 month and 6 month markets establishes covered interest parity as a possible long run equilibrium relationship for the sample period. However, both a well defined EC mechanism and the fact that past changes in the interest rate differential help predict the forward premium suggest the markets did not utilise all available information efficiently. Neither the 3 month not he 6 month forward rate cointegrate with the spot rate implying that these variables may have drifted apart over the sample period. Speculative efficiency may be rejected for these markets.