Identifying collapsed buildings

THE WORK TO RECOVER AND REBUILD FOLLOWING an earthquake requires reliable information on the condition of structures in the affected areas. In developed areas, efforts to gather this information can be time-consuming and prone to errors, often resulting in incomplete or inaccurate information. A new, software-based methodology to recognize collapsed buildings utilizes classification of satellite images combined with height variation information. The methodology was demonstrated in a full-scale, real-life scenario by a team led by Prof. Valerio Baiocchi of the University of Rome. According to Baiocchi, the team’s work was intended to demonstrate the methodology on actual data available for the entire city of L’Aquila in the Abruzzo region of central Italy, in an actual and complete simulation of quick damage assessment in a real emergency. The team utilized satellite imagery of the city of L’Aquila, which experienced a magnitude 6.3 earthquake on April 6, 2009. The work demonstrated a robust classification of collapsed structures that was completed quickly and with good confidence

A new methodology to manage Italian geodetic datums of the cadastral systems and of the historic maps

Cadastral maps represent the result of the highest scale survey of any region. They are not topographic maps. Their goal is to show the property system of the mapped area, so any topographic element that is important for this aspect is shown while others often omitted. Historical cadastral sheets provide valuable information about not only the natural and built environment but also about some aspects of the society of the time of the survey. Because of their high scale, their creation is extremely expensive. Even the updating of the cadastre claims considerable funds from the state budgets. That is why the coordinate system, the geodetic basis of a cadastral work is rarely changed. Re-ambulation is often made on the basis of the older version, following their geodetic and topographic 'skeleton'. The main period of the cadastral works in Europe was the first two thirds of the nineteenth century. Countries that gained their independency after this period have quite complicated cadastral systems, more or less preserving the political distribution of their lands of the time of cadastral mapping. Besides Germany, Italy provides the best example to this. Concerning Italy, the complete unification of the country was in 1870. To this time, a large part of the Apennine Peninsula was covered by cadastral surveys, mainly carried out by Piedmont, the Kingdom of Naples, and the Papal State as reported by Frazzica et al. (Geophysical Research Abstracts 11:4791, 2009). After the WWI, territorial gains from the former Habsburg Empire resulted three new cadastral systems to be incorporated (one of them 'lost' after WWII). Together with them, nowadays, Italy has 31 major ("grandi origini") and more than 800 smaller, local ("piccole origini") cadastral systems; all of them have its own projection origin (Fig. 1; Baiocchi et al. 2011). At some smaller parts of the country, the modern national map grid system was later introduced and applied as reported by Moncada (1948), Bonifacino (1953), and Giucucci (Rivista del Catasto e dei Servizi Tecnici Erariali 8(2):109-113, 1953). Fortunately, the story of the related geodetic datums was simplified prior to nowadays. Of course, the abovementioned systems had several trigonomentric networks as geodetic bases. In the first decades of the twentieth century, however, the Italian Institute of Military Geography (Istituto Geografico Militare; I.G.M) developed four geodetic networks, all on the Bessel 1841 ellipsoid; the Genova 1902 (Fig. 2), the old Monte Mario (Fig. 3), the Castanea delle Furie 1910, and the Guardia Vecchia (Fig. 4) datums, for northern, central, and southern Italy and Sardinia, respectively (Mori 1922). However, these systems were independent ones; afterward, one of them, the Genova 1902 datum, was extended to cover other parts of the country. Outside of northern Italy, the original area of this datum, the coordinates of the basepoint, and the cadastral system origins were transformed from the locally valid network to Genova 1902 datum. The present paper aims to estimate the accuracy of this extension of that system and to describe the parameters of the other systems for GIS applications, thus offering a tool for future, higher accuracy methods to fit the cadastral maps of southern Italy and Sardinia to modern grids. This can be useful also to convert some older technical maps that were referred to the same geodetic datums. © 2013 Società Italiana di Fotogrammetria e Topografia (SIFET)

Horizontal accuracy assessment of very high resolution Google Earth images in the city of Rome, Italy

Google Earth (GE) has recently become the focus of increasing interest and popularity among available online virtual globes used in scientific research projects, due to the free and easily accessed satellite imagery provided with global coverage. Nevertheless, the uses of this service raises several research questions on the quality and uncertainty of spatial data (e.g. positional accuracy, precision, consistency), with implications for potential uses like data collection and validation. This paper aims to analyze the horizontal accuracy of very high resolution (VHR) GE images in the city of Rome (Italy) for the years 2007, 2011, and 2013. The evaluation was conducted by using both Global Positioning System ground truth data and cadastral photogrammetric vertex as independent check points. The validation process includes the comparison of histograms, graph plots, tests of normality, azimuthal direction errors, and the calculation of standard statistical parameters. The results show that GE VHR imageries of Rome have an overall positional accuracy close to 1 m, sufficient for deriving ground truth samples, measurements, and large-scale planimetric maps

Evaluation of the damages caused by seismic events: First tests on supporting traditional multispectral classification with DSM

Seismic damages, as a roof entirely collapsed on the ground, are very difficult to be found using only multispectral classification algorithms. The availability of high resolution stereopairs from satellite disclose new possible fields of application to estimate changes and transformations of areas following catastrophic events. Combining both techniques it is obviously possible only when stereoscopic and multispectral images are available. In this case, as for all monitoring studies, it is necessary to compare the present situation to the pre-seismic one. The pre-seismic situation can be advantageously studied by classic photogrammetric techniques based on aerial frames, that are available in archives managed by photogrammetric companies and local government agencies. But it is also possible to extract the pre-seismic morphology from digital maps, containing the three-dimensional characteristics of the buildings. The present research tries to: a) improve the digital surface model extracted from Ikonos satellite images covering an area of central Italy (Foligno, Umbria), through a pre-treatment of images and a manual editing b) study the best DSM models to improve the detection of height difference, mainly in urban areas, and evaluate the results of the classification of land cover as further data to detect changes in building shape. DSM obtained by three-dimensional maps have been compared with DSM extracted directly from aerial stereo-pairs using different approaches. In the area under study a seismic event happened in September of the '97 causing relevant damages to different urbanized centres of the area

Dispersal and Repulsion of Entomopathogenic Nematodes to Prenol.

Chemosensory cues are crucial for entomopathogenic nematodes (EPNs)-a guild of insect-killing parasitic nematodes that are used as biological control agents against a variety of agricultural pests. Dispersal is an essential element of the EPN life cycle in which newly developed infective juveniles (IJs) emerge and migrate away from a resource-depleted insect cadaver in order to search for new hosts. Emergence and dispersal are complex processes that involve biotic and abiotic factors, however, the elements that result in EPN dispersal behaviors have not been well-studied. Prenol is a simple isoprenoid and a natural alcohol found in association with EPN-infected, resource-depleted insect cadavers, and this odorant has been speculated to play a role in dispersal behavior in EPNs. This hypothesis was tested by evaluating the behavioral responses of five different species of EPNs to prenol both as a distal-chemotactic cue and as a dispersal cue. The results indicate that prenol acted as a repulsive agent for all five species tested, while only two species responded to prenol as a dispersal cue

Touch-stimulation increases host-seeking behavior in Steinernema Carpocapsae.

Previous research demonstrated that Steinernema carpocapsae infective juveniles (IJs) exposed to a host cuticle were more attracted toward certain host-associated volatile odors. We wanted to test the specificity of attraction that results from exposure to host cuticle. Host recognition behavior was analyzed after stimulating IJs by allowing them to physically interact with Galleria mellonella cuticles. The subsequent behavioral response and the proportion of the population participating in chemotaxis to multiple host odors were measured. We found that exposure to host cuticles resulted in a significantly higher percentage of the population participating in host-seeking behavior, with threefold more nematodes participating in chemotaxis. We tested whether exposure to live or dead host cuticle resulted in a different response and found that a higher percentage of IJs exposed to a live host cuticle participated in chemotaxis than IJs exposed to a dead host cuticle, but that IJs exposed to a dead host demonstrated significantly higher participation than was observed for non-stimulated IJs. To test whether the increase in IJ participation in host-seeking behaviors after exposure to a live host cuticle was specific, we exposed stimulated IJs to a known repulsive odor, a neutral odor, and two predicted attractants. We found that stimulation of IJs through physical contact with a host cuticle induces a specific enhancement of host-seeking behavior to host-specific odors rather than a general increased chemotactic response to all volatile stimuli. However, the nematodes displayed an enhanced response to multiple host-specific odors. Future work should focus on the mechanism through which contact with live host cuticle stimulates increased behavioral response.Previous research demonstrated that Steinernema carpocapsae infective juveniles (IJs) exposed to a host cuticle were more attracted toward certain host-associated volatile odors. We wanted to test the specificity of attraction that results from exposure to host cuticle. Host recognition behavior was analyzed after stimulating IJs by allowing them to physically interact with Galleria mellonella cuticles. The subsequent behavioral response and the proportion of the population participating in chemotaxis to multiple host odors were measured. We found that exposure to host cuticles resulted in a significantly higher percentage of the population participating in host-seeking behavior, with threefold more nematodes participating in chemotaxis. We tested whether exposure to live or dead host cuticle resulted in a different response and found that a higher percentage of IJs exposed to a live host cuticle participated in chemotaxis than IJs exposed to a dead host cuticle, but that IJs exposed to a dead host demonstrated significantly higher participation than was observed for non-stimulated IJs. To test whether the increase in IJ participation in host-seeking behaviors after exposure to a live host cuticle was specific, we exposed stimulated IJs to a known repulsive odor, a neutral odor, and two predicted attractants. We found that stimulation of IJs through physical contact with a host cuticle induces a specific enhancement of host-seeking behavior to host-specific odors rather than a general increased chemotactic response to all volatile stimuli. However, the nematodes displayed an enhanced response to multiple host-specific odors. Future work should focus on the mechanism through which contact with live host cuticle stimulates increased behavioral response

Integrated surveying for the archaeological documentation of a neolithic site

It has been tested the applicability of integrated surveys (remote sensing, digital photogrammetry and terrestrial laser scanning (TLS)) in order to verify, through gradual and successive steps, how geomatic techniques can get 3D results with metric value combined with a quality content for an archaeological site. In particular, the data have been collected during the excavation campaign of Neolithic archaeological site in Taranto. The possibilities to scan articulated forms, in the presence of curve, concavity and convexity, and jutting parts rotate, characterized by alterations, through the acquisition of a dense points cloud makes the technique TLS needed in archaeology. Through the photogrammetric technique the laser data has been integrated concerning some details found on the site for which it has been required a higher degree of detail. The photogrammetric data has been acquired with the calibrated camera. The processing of the acquired data and their integration has been made possible to study an important archeological site, in its totality, from small scale (general site framework) to large scale (3D model with a high degree of detail) and to structure a multi-temporal database for simplified data management

Adaptive conflict-free optimization of rule sets for network security packet filtering devices

Packet filtering and processing rules management in firewalls and security gateways has become commonplace in increasingly complex networks. On one side there is a need to maintain the logic of high level policies, which requires administrators to implement and update a large amount of filtering rules while keeping them conflict-free, that is, avoiding security inconsistencies. On the other side, traffic adaptive optimization of large rule lists is useful for general purpose computers used as filtering devices, without specific designed hardware, to face growing link speeds and to harden filtering devices against DoS and DDoS attacks. Our work joins the two issues in an innovative way and defines a traffic adaptive algorithm to find conflict-free optimized rule sets, by relying on information gathered with traffic logs. The proposed approach suits current technology architectures and exploits available features, like traffic log databases, to minimize the impact of ACO development on the packet filtering devices. We demonstrate the benefit entailed by the proposed algorithm through measurements on a test bed made up of real-life, commercial packet filtering devices