Volcanic eruptions are preceded by a series of detectable phenomena related to: i) rise of magma ... more Volcanic eruptions are preceded by a series of detectable phenomena related to: i) rise of magma and gas from deep, dike-filling intrusions, ii) increase in magma pressures within conduits, iii) inflation of volcanic edifices.. Ground deformation resulting from volcano inflation can be recorded by various techniques as the recent ground-based radar interferometry (GB-InSAR). Here we present GB-InSAR deformation data (interferograms) collected at Stromboli volcano (Aeolian Islands, Southern Italy) over the period 2008-2011 ...
This paper presents results from applying semi-automatic point cloud segmentation methods in the ... more This paper presents results from applying semi-automatic point cloud segmentation methods in the underground tunnels within the Military Shrine’s conservative restoration project in Cima Grappa (Italy). The studied area, which has a predominant underground development distributed in a network of tunnels, is characterized by diffuse rock collapsing. In such a context, carrying out surveys and other technical operations are dangerous activities. Considering safety restrictions and unreachable impervious tunnels, having approached the study area with the scan-line survey technique resulted in only partial rock mass characterization. Hence, the geo-mechanical dataset was integrated, applying a semi-automatic segmentation method to the point clouds acquired through terrestrial laser scanning (TLS). The combined approach allowed for remote performance of detailed rock mass characterization, even remotely, in a short time and with a limited operators presence on site. Moreover, it permitte...
Improved structure of liquid sampler (1) for underwater inspections comprising a hollow container... more Improved structure of liquid sampler (1) for underwater inspections comprising a hollow container body (10) having a longitudinal recess (15) in which it is slidingly mounted a piston (20). This divides the longitudinal recess (15) in a first containing chamber (30) hydraulically connected with the outside environment through at least one opening (31), and in a second containing chamber (40) equipped with at least one inlet mouth (41). Furthermore, a actuation device (60,70) is provided arranged to selectively arrange the or each inlet mouth (41) between a closed configuration, in which the second containing chamber (40) is hydraulically insulated from the outside environment and the first containing chamber (30) is flooded, and an open configuration, in which the second containing chamber (40) is hydraulically connected with the outside environment. The actuation device (60,70) is adapted, moreover, to cause a translation of the piston (20) in the longitudinal recess (15) from a fi...
Abstract. The work presents a survey campaign specifically designed to formulate an effective res... more Abstract. The work presents a survey campaign specifically designed to formulate an effective restoration project in a Cultural Heritage context, the Military Shrine in Cima Grappa (Italy). Several outputs have been generated by exploring the most advanced laser scanning survey technique and some specific point cloud analysis algorithms. A detailed geometrical 3D reconstruction of human-made and natural tunnels coating materials, a geo-mechanical survey of the rock mass, a map of rock collapses and cinematic analysis of instability processes.Integrating Laser Scanning technique with the Scan-line survey allowed to perform advanced analysis and rock-mass characterisation in a predominant subterranean developed area. Most of the tunnels and underground spaces displayed rock collapses and diffuse active instability processes that certainly could have drastically slowed down surveys and analysis. The adopted techniques allowed both to proceed in acquiring data end in delivering sound ou...
The terrestrial laser scanning (TLS) technique has been used to accurately reconstruct the 3-D sh... more The terrestrial laser scanning (TLS) technique has been used to accurately reconstruct the 3-D shape of the walls and bastions of the historic city of Mdina (Malta) and underlying terrain. By applying this technique it has also been possible to extract additional quantitative information regarding weathering and deformational processes affecting the structures. Thus, with the aim of identifying the main instability mechanisms, a detailed 3-D crack distribution map has been drawn and the main displacement vectors have been defined.
One of the most difficult challenge in the everyday practice to describe the canopy growing of fr... more One of the most difficult challenge in the everyday practice to describe the canopy growing of fruit trees in an orchard. Thephotosynthetic activity is the basic of the primer production of plants. The measurement of leaf area and determination of thephotosynthetic activity could be occurred with some elaborated methods between experimental conditions. In this article we present such anintegrated methodology, which is ideal to determine the geometric and spectral characteristic of fruit trees between field conditions.We havecarried out laser scanning technology to investigate the geometric-topological characteristics and parallel the active infra-red sensor to collectspectral data about an apple orchard. The surveys were worked out in an intensive apple orchard with drip irrigation system, protected by hailnet in Study and Regional Research Farm of the University of Debrecen near Pallag. This study shows the filtering and interpretation methodsof created data. The produced high accu...
An innovative wireless sensor network (WSN) based on Ultra-Wide Band (UWB) technology for 3D accu... more An innovative wireless sensor network (WSN) based on Ultra-Wide Band (UWB) technology for 3D accurate superficial monitoring of ground deformations, as landslides and subsidence, is proposed. The system has been designed and developed as part of an European Life+ project, called Wi-GIM (Wireless Sensor Network for Ground Instability Monitoring). The details of the architecture, the localization via wireless technology and data processing protocols are described. The flexibility and accuracy achieved by the UWB two-way ranging technique is analysed and compared with the traditional systems, such as robotic total stations (RTSs) and Ground-based Interferometric Synthetic Aperture Radar (GB-InSAR), highlighting the pros and cons of the UWB solution to detect the surface movements. An extensive field trial campaign allows the validation of the system and the analysis of its sensitivity to different factors (e.g., sensor nodes inter-visibility, effects of the temperature, etc.). The Wi-G...
Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, 2017
Remotely operated underwater vehicles are mobile robots increasingly used in underwater applicati... more Remotely operated underwater vehicles are mobile robots increasingly used in underwater applications; these devices are widely used and suitable for different scenarios, for example, for patrolling and monitoring and also for underwater interventions. In the last 30 years, the remotely operated underwater vehicles have become more and more advanced; at the same rate with the progressive technological development of these vehicles, the market of the specialized component industry is fast-increasing. Generally speaking, a remotely operated underwater vehicle allows to investigate areas inaccessible or too dangerous for human beings. The use of remotely operated underwater vehicles during a mission, with the related implication of support ships and specialized pilots, or the involvement of professional divers, is usually associated with high costs. The reduction of these costs is an important topic in the underwater robotic field and the easy piloting of these mobile robots is a crucia...
ABSTRACT At Stromboli volcano (Southern Italy), only few minor precursors (gas output) have been ... more ABSTRACT At Stromboli volcano (Southern Italy), only few minor precursors (gas output) have been identified for 'major' Strombolian explosions. We use ground-based interferometric synthetic aperture radar (GBInSAR) technology to monitor the displacement rate of the summit area of Stromboli. We analysed the 2009-2011 period. We analysed three major explosion-dominated periods: March-May 2009, November 2009-January 2010 and June-September 2011. The analysis of the displacement rate has been performed by dividing the summit zone monitored by the GBInSAR into three regions, corresponding to the edge of the craters area (1 and 2), and to the slope of the NE crater (3, Figs 1b and 3). Sector 3 is generally decorrelated in interferograms spanning more than 12 h due to the fast accumulation and remobilization of ejecta. During the three analysed anomalous periods, sector 3 is characterized by higher coherence and hence the increase in the displacement rate has been measured. Short-term interferograms (11 min) are used to measure the syn-explosive displacement and also to locate fast lava flows in sector 3, which are easily visible due to the high loss of coherence compared with the surrounding area. The ability of InSAR to measure volcano deformation depends on the persistence of phase coherence over appropriate time intervals on various types of volcanic deposits. Loss in coherence depends on chaotic ground movements (e.g. debris avalanches) while higher coherence is related to coherent displacements. An increase in the displacement of sector 3 has been observed since 20 March 2009, when the deformation pattern changed and the coherence of the radar image of that zone increased from low values (rolling of incoherent material on the cone slope) to values higher than >0.8 (coherence threshold). The deforming area was very localized and stable in its extent, involving approximately 15 × 103 m2 of the NE cone base. The maximum displacement rate was reached on the 27 March 2009 (0.35 mm h-1), 2 days before the lava outflow from the summit craters (29 March), but the displacement rate of the summit area remained high for the following 2 months, with peaks on 3 April (0.27 mm h-1), 14 April (0.3 mm h-1), 3 May (0.25 mm h-1) and 22 May (0.23 mm h-1). The peak of 3 May corresponds to the displacement related to the major explosion that also was observed in sectors 1 and 2. Displacement rates during the November 2009-January 2010 period were subject to a higher degree of variation than March-May 2009, with some peaks in correspondence with the major explosions and others, which occurred some days before them. In particular, an increase in displacement rate was observed starting from 2 November 2009 (0.56 mm h-1) that ended with the explosion of 8 November (0.6 mm h-1). Similar trends have been observed in the periods between (i) 19 and 23 November (0.25-0.3 mm h-1), (ii) 20 and 28 December (0.25-0.29 mm h-1), (iii) 6 and 9 January (0.24-0.29 mm h-1) and finally, (iv) 16 and 20 January 2010 (0.2-0.3 mm h-1). The GBInSAR revealed that displacements in sectors 1 and 2 occurred only during the 8 November 2009, 24 November 2009 and 21 January 2010 major explosions. Analysing the data before 20 June 2011, an increase in the displacement rate has been detected in sector 3 in the period 9-18 May. Displacements have been observed during the night between 8 and 9 May, with an increase in the displacement rate at the base of the NE crater area up to 0.38 mm h-1. The displacement rate reached its peak during the early morning of 10 May and then gradually decreased. The GBInSAR revealed displacements in the crater area (sectors 1 and 2) only during the 20 June and 5 July explosions. The occurrence of the 1-2 August 2011 lava flow from the NE cone on the SdF and its subsequent remobilization, promoting small-scale instability on the SdF, has also been recognized. Pulses of rapid expansion of sector 3, of variable duration and amplitude, appear in coincidence with periods of intense activity that include lava flows and major explosions. We associate this expansion with the pressurization of the magma column that is recharged by deep-derived gas, promoting the onset of 'major explosion-dominated' activity.
Volcanic eruptions are preceded by a series of detectable phenomena related to: i) rise of magma ... more Volcanic eruptions are preceded by a series of detectable phenomena related to: i) rise of magma and gas from deep, dike-filling intrusions, ii) increase in magma pressures within conduits, iii) inflation of volcanic edifices.. Ground deformation resulting from volcano inflation can be recorded by various techniques as the recent ground-based radar interferometry (GB-InSAR). Here we present GB-InSAR deformation data (interferograms) collected at Stromboli volcano (Aeolian Islands, Southern Italy) over the period 2008-2011 ...
This paper presents results from applying semi-automatic point cloud segmentation methods in the ... more This paper presents results from applying semi-automatic point cloud segmentation methods in the underground tunnels within the Military Shrine’s conservative restoration project in Cima Grappa (Italy). The studied area, which has a predominant underground development distributed in a network of tunnels, is characterized by diffuse rock collapsing. In such a context, carrying out surveys and other technical operations are dangerous activities. Considering safety restrictions and unreachable impervious tunnels, having approached the study area with the scan-line survey technique resulted in only partial rock mass characterization. Hence, the geo-mechanical dataset was integrated, applying a semi-automatic segmentation method to the point clouds acquired through terrestrial laser scanning (TLS). The combined approach allowed for remote performance of detailed rock mass characterization, even remotely, in a short time and with a limited operators presence on site. Moreover, it permitte...
Improved structure of liquid sampler (1) for underwater inspections comprising a hollow container... more Improved structure of liquid sampler (1) for underwater inspections comprising a hollow container body (10) having a longitudinal recess (15) in which it is slidingly mounted a piston (20). This divides the longitudinal recess (15) in a first containing chamber (30) hydraulically connected with the outside environment through at least one opening (31), and in a second containing chamber (40) equipped with at least one inlet mouth (41). Furthermore, a actuation device (60,70) is provided arranged to selectively arrange the or each inlet mouth (41) between a closed configuration, in which the second containing chamber (40) is hydraulically insulated from the outside environment and the first containing chamber (30) is flooded, and an open configuration, in which the second containing chamber (40) is hydraulically connected with the outside environment. The actuation device (60,70) is adapted, moreover, to cause a translation of the piston (20) in the longitudinal recess (15) from a fi...
Abstract. The work presents a survey campaign specifically designed to formulate an effective res... more Abstract. The work presents a survey campaign specifically designed to formulate an effective restoration project in a Cultural Heritage context, the Military Shrine in Cima Grappa (Italy). Several outputs have been generated by exploring the most advanced laser scanning survey technique and some specific point cloud analysis algorithms. A detailed geometrical 3D reconstruction of human-made and natural tunnels coating materials, a geo-mechanical survey of the rock mass, a map of rock collapses and cinematic analysis of instability processes.Integrating Laser Scanning technique with the Scan-line survey allowed to perform advanced analysis and rock-mass characterisation in a predominant subterranean developed area. Most of the tunnels and underground spaces displayed rock collapses and diffuse active instability processes that certainly could have drastically slowed down surveys and analysis. The adopted techniques allowed both to proceed in acquiring data end in delivering sound ou...
The terrestrial laser scanning (TLS) technique has been used to accurately reconstruct the 3-D sh... more The terrestrial laser scanning (TLS) technique has been used to accurately reconstruct the 3-D shape of the walls and bastions of the historic city of Mdina (Malta) and underlying terrain. By applying this technique it has also been possible to extract additional quantitative information regarding weathering and deformational processes affecting the structures. Thus, with the aim of identifying the main instability mechanisms, a detailed 3-D crack distribution map has been drawn and the main displacement vectors have been defined.
One of the most difficult challenge in the everyday practice to describe the canopy growing of fr... more One of the most difficult challenge in the everyday practice to describe the canopy growing of fruit trees in an orchard. Thephotosynthetic activity is the basic of the primer production of plants. The measurement of leaf area and determination of thephotosynthetic activity could be occurred with some elaborated methods between experimental conditions. In this article we present such anintegrated methodology, which is ideal to determine the geometric and spectral characteristic of fruit trees between field conditions.We havecarried out laser scanning technology to investigate the geometric-topological characteristics and parallel the active infra-red sensor to collectspectral data about an apple orchard. The surveys were worked out in an intensive apple orchard with drip irrigation system, protected by hailnet in Study and Regional Research Farm of the University of Debrecen near Pallag. This study shows the filtering and interpretation methodsof created data. The produced high accu...
An innovative wireless sensor network (WSN) based on Ultra-Wide Band (UWB) technology for 3D accu... more An innovative wireless sensor network (WSN) based on Ultra-Wide Band (UWB) technology for 3D accurate superficial monitoring of ground deformations, as landslides and subsidence, is proposed. The system has been designed and developed as part of an European Life+ project, called Wi-GIM (Wireless Sensor Network for Ground Instability Monitoring). The details of the architecture, the localization via wireless technology and data processing protocols are described. The flexibility and accuracy achieved by the UWB two-way ranging technique is analysed and compared with the traditional systems, such as robotic total stations (RTSs) and Ground-based Interferometric Synthetic Aperture Radar (GB-InSAR), highlighting the pros and cons of the UWB solution to detect the surface movements. An extensive field trial campaign allows the validation of the system and the analysis of its sensitivity to different factors (e.g., sensor nodes inter-visibility, effects of the temperature, etc.). The Wi-G...
Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment, 2017
Remotely operated underwater vehicles are mobile robots increasingly used in underwater applicati... more Remotely operated underwater vehicles are mobile robots increasingly used in underwater applications; these devices are widely used and suitable for different scenarios, for example, for patrolling and monitoring and also for underwater interventions. In the last 30 years, the remotely operated underwater vehicles have become more and more advanced; at the same rate with the progressive technological development of these vehicles, the market of the specialized component industry is fast-increasing. Generally speaking, a remotely operated underwater vehicle allows to investigate areas inaccessible or too dangerous for human beings. The use of remotely operated underwater vehicles during a mission, with the related implication of support ships and specialized pilots, or the involvement of professional divers, is usually associated with high costs. The reduction of these costs is an important topic in the underwater robotic field and the easy piloting of these mobile robots is a crucia...
ABSTRACT At Stromboli volcano (Southern Italy), only few minor precursors (gas output) have been ... more ABSTRACT At Stromboli volcano (Southern Italy), only few minor precursors (gas output) have been identified for 'major' Strombolian explosions. We use ground-based interferometric synthetic aperture radar (GBInSAR) technology to monitor the displacement rate of the summit area of Stromboli. We analysed the 2009-2011 period. We analysed three major explosion-dominated periods: March-May 2009, November 2009-January 2010 and June-September 2011. The analysis of the displacement rate has been performed by dividing the summit zone monitored by the GBInSAR into three regions, corresponding to the edge of the craters area (1 and 2), and to the slope of the NE crater (3, Figs 1b and 3). Sector 3 is generally decorrelated in interferograms spanning more than 12 h due to the fast accumulation and remobilization of ejecta. During the three analysed anomalous periods, sector 3 is characterized by higher coherence and hence the increase in the displacement rate has been measured. Short-term interferograms (11 min) are used to measure the syn-explosive displacement and also to locate fast lava flows in sector 3, which are easily visible due to the high loss of coherence compared with the surrounding area. The ability of InSAR to measure volcano deformation depends on the persistence of phase coherence over appropriate time intervals on various types of volcanic deposits. Loss in coherence depends on chaotic ground movements (e.g. debris avalanches) while higher coherence is related to coherent displacements. An increase in the displacement of sector 3 has been observed since 20 March 2009, when the deformation pattern changed and the coherence of the radar image of that zone increased from low values (rolling of incoherent material on the cone slope) to values higher than >0.8 (coherence threshold). The deforming area was very localized and stable in its extent, involving approximately 15 × 103 m2 of the NE cone base. The maximum displacement rate was reached on the 27 March 2009 (0.35 mm h-1), 2 days before the lava outflow from the summit craters (29 March), but the displacement rate of the summit area remained high for the following 2 months, with peaks on 3 April (0.27 mm h-1), 14 April (0.3 mm h-1), 3 May (0.25 mm h-1) and 22 May (0.23 mm h-1). The peak of 3 May corresponds to the displacement related to the major explosion that also was observed in sectors 1 and 2. Displacement rates during the November 2009-January 2010 period were subject to a higher degree of variation than March-May 2009, with some peaks in correspondence with the major explosions and others, which occurred some days before them. In particular, an increase in displacement rate was observed starting from 2 November 2009 (0.56 mm h-1) that ended with the explosion of 8 November (0.6 mm h-1). Similar trends have been observed in the periods between (i) 19 and 23 November (0.25-0.3 mm h-1), (ii) 20 and 28 December (0.25-0.29 mm h-1), (iii) 6 and 9 January (0.24-0.29 mm h-1) and finally, (iv) 16 and 20 January 2010 (0.2-0.3 mm h-1). The GBInSAR revealed that displacements in sectors 1 and 2 occurred only during the 8 November 2009, 24 November 2009 and 21 January 2010 major explosions. Analysing the data before 20 June 2011, an increase in the displacement rate has been detected in sector 3 in the period 9-18 May. Displacements have been observed during the night between 8 and 9 May, with an increase in the displacement rate at the base of the NE crater area up to 0.38 mm h-1. The displacement rate reached its peak during the early morning of 10 May and then gradually decreased. The GBInSAR revealed displacements in the crater area (sectors 1 and 2) only during the 20 June and 5 July explosions. The occurrence of the 1-2 August 2011 lava flow from the NE cone on the SdF and its subsequent remobilization, promoting small-scale instability on the SdF, has also been recognized. Pulses of rapid expansion of sector 3, of variable duration and amplitude, appear in coincidence with periods of intense activity that include lava flows and major explosions. We associate this expansion with the pressurization of the magma column that is recharged by deep-derived gas, promoting the onset of 'major explosion-dominated' activity.
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Papers by Francesco Mugnai