560 research outputs found

    Geomatics supporting knowledge of cultural heritage aimed at recovery and restoration

    Get PDF
    The study presented aims a practical contribution to the use of the Terrestrial Laser Scanner and the Close Range Photogrammetry geomatic techniques and to their integration for the knowledge and development of the historical-architectural heritage, both in the step of planning a restorative conservation project, and in the subsequent step of the restoration works. In particular, these techniques and their integration were applied at the process of study, planning and execution of the restoration of the San Giovanni Battista church in Fonni (Sardinia, Italy), founded in the 16th century. The building, due to structural problems and humidity infiltrations, was subject to a serious intervention for consolidation and conservative restoration.In the first phase of the work, preliminary to the design, a TLS survey was made that allowed to obtain an accurate 3D model of the church. In a second phase, during the restoration work, CRP surveys were carried out and the accuracy of this technique was verified through a comparison with TLS surveys. The integration of the two techniques to improve the texture of point clouds detected with TLS was also tested

    Functional models and extending strategies for ecological networks

    Get PDF
    Complex network analysis is rising as an essential tool to understand properties of ecological landscape networks, and as an aid to land management. The most common methods to build graph models of ecological networks are based on representing functional connectivity with respect to a target species. This has provided good results, but the lack of a model able to capture general properties of the network may be seen as a shortcoming when the activity involves the proposal for modifications in land use. Similarity scores, calculated between nature protection areas, may act as a building block for a graph model intended to carry a higher degree of generality. The present work compares several design choices for similarity-based graphs, in order to determine which is most suitable for use in land management

    Laboratory tests on hydraulic lime mortar reinforced with jute fibres

    Get PDF
    Background: Considering the high seismic vulnerability of masonry buildings located in the Italian territory, the implementation of seismic retrofit programs is strongly needed.. With consideration for sustainable interventions, it is evident that the retrofit techniques to protect the historical heritage should be carried out with innovative green compound materials, such as mortars reinforced with natural fibres. Objective: In the current paper, laboratory tests on lime mortars strengthened with raw jute fibres have been performed. Methods: The workability of the fibre-reinforced mixture has been assessed through shaking table tests, and the mechanical resistances of standard specimens have been evaluated by bending and compression tests. Results: Considering the hygroscopic nature of jute, it has been identified that the optimal water/lime ratio and the maximum water percentage are absorbed by jute fibres. From the results, how the spreading of the mixture, which is indicative of the mortar consistency, changes with the water/lime ratio, has been evaluated. From bending tests, the effective behaviour of fibres, which provide a stitching effect of the failure crack in the investigated fibre-reinforced lime mortars, has been observed. Conclusion: Finally, the results of compression tests have shown that the examined fibre-reinforced mortars can be effectively used as building products according to the actual Italian technical code NTC 2018

    TERRESTRIAL LASER SCANNER FOR MONITORING THE DEFORMATIONS AND THE DAMAGES OF BUILDINGS

    Get PDF
    scanner provides the ability to detect the geometric 3D model of a building without any physical contact with the structure. Knowledge of the 3D model will give the opportunity to study the deformation and quantify the damages. Three case studies are presented relating to damaged and/or unsafe buildings: Sivillier Castle (Villasor - Sardinia- Italy), the Bell Tower of Mores (Sardinia-Italy) and industrial building (Cagliari - Italy). The first two cases concern buildings of historical and architectural importance that present a state of compromised conservation; the last, an industrial building compromised by fire. In all cases, a laser scanner survey was carried out that not only provided valuable information but also highlighted structural metric deformation and degradation

    Perbedaan Hasil Belajar Siswa Menggunakan Metode Pembelajaran Kooperatif Tipe Student Facilitator And Explaining dengan Metode Pembelajaran Ceramah pada Mata Pelajaran Ekonomi Kelas XI SMA Negeri 4 Padang

    Full text link
    The background of this research is the lower of student economics result in the class XI SMA N 4 Padang, 2013 / 2014 period. This matter is caused by the lack of student activity in learning process. The aim of this research is to know how the Difference Result of Student learning by using study Co-Operative method of Student Facilitator and Explaining type with Discourse Method in SMA N 4 Padang. Based on data analysis result is found average value 73,26 for class experiment and 62,77 for class control. From data analysis result is known value of thitung = 2,978 that is bigger than value of ttabel = 1,67 meaning raised to be hypothesis to be accepted at real level α = 0,05. This matter indicate that there are significant difference between student learning result by using study co-operative method of student explaining and facilitator type with discourse method. Its mean that the result of student economics learning by using study co-operative method of Student Facilitator And Explaining type is better than discourse method at class XI SMA N 4 Padang

    The Epidemiology of Fractures and Muskulo-Skeletal Traumas During COVID-19 Lockdown: A Detailed Survey of 17.591 Patients in a Wide Italian Metropolitan Area

    Get PDF
    Introduction: On 9 March 2020 the Italian Government declared a national lockdown to curb the spread of Covid-19. The aim of our study was to analyze the effects of such intervention on the traumatological emergency service, with particular emphasis on variations in trauma incidence and patients’ characteristics. Materials and Methods: An observational analysis was performed. Medical records were collected from 3 different trauma centers within a wide metropolitan area, and compared between 2 time periods: the full Italian lockdown period and the same period from the past year. The study population included all patients who were admitted to the Emergency Department (ED). For those who accessed for orthopedic reasons, the analyzed variables included the date of ED admission, age, gender, after visit discharge or hospitalization, place where the injury occurred, traumatic mechanism, diagnosis, relationship with sport activity, and time from injury/symptoms debut to ED access. Results: A total of 17591 ED accesses and 3163 ED trauma visits were identified. During the lockdown, ED trauma visits decreased by -59.8%, but required patient’s hospitalization significantly more frequently. The rate of ED trauma admissions in the elderlies significantly increased, together with the proportion of fragility fractures such as hip fractures. Road accident traumas (-79.6%) and sport-related injuries (-96.2%) significantly dropped. Admissions for less-severe reasons such as atraumatic musculoskeletal pain significantly decreased (-81.6%). Conclusions: The lockdown reduced the pressure on the Health System in at least 2 ways: directly, by curbing viral transmission and indirectly, by more than halving the ED trauma visits. Nonetheless, we observed an increased proportion of traumas in older patients, requiring hospitalizations, while the rate of less-severe cases decreased. This analysis may raise awareness of the effects of a lockdown on trauma services and may be helpful for those ones around the world who are now facing the emergency

    Importance of plants with extremely small populations (Psesps) in endemic-rich areas, elements often forgotten in conservation strategies

    Get PDF
    The distribution of the threatened fern Ophioglossum vulgatum L., a plant with extremely small populations (PSESPs) in Sardinia, is characterized by small disjunct populations with only a few individuals, and little is known about its status in the wild. To provide information for the conservation of O. vulgatum and with the aim to develop an in situ conservation strategy, we investigated its distribution, population size, and habitat. Field surveys confirmed that the species grows in only five localities. Two representative populations were selected for this study (Funtanamela and Gedili), and in each population, all plants were mapped and monitored monthly from April to August over an 8-year period. During the study, the populations had a very low number of reproductive plants and the populations appeared to be in decline, with the total number of plants per population slightly decreased in Gedili while a sharp reduction was recorded in Funtanamela due to wild boar threat. A fence was built in order to protect the site from further damage, but no noticeable signals of recovery were observed. The most urgent conservation requirement for this species is to preserve the threatened habitat of the remnant populations. Further field surveys and research are also required for an improved understanding of the species’ status

    Using Remote Monitoring And Machine Learning To Classify Slam Events Of Wave Piercing Catamarans

    Get PDF
    An onboard monitoring system can measure features such as stress cycles counts and provide warnings due to slamming. Considering current technology trends there is the opportunity of incorporating machine learning methods into monitoring systems. A hull monitoring system has been developed and installed on a 111 m wave piercing catamaran (Hull 091) to remotely monitor the ship kinematics and hull structural responses. Parallel to that, an existing dataset of a similar vessel (Hull 061) was analysed using unsupervised and supervised learning models; these were found to be beneficial for the classification of bow entry events according to key kinematic parameters. A comparison of different algorithms including linear support vector machines, naĂŻve Bayes and decision tree for the bow entry classification were conducted. In addition, using empirical probability distributions, the likelihood of wet-deck slamming was estimated given a vertical bow acceleration threshold of 1 in head seas, clustering the feature space with the approximate probabilities of 0.001, 0.030 and 0.25
    • …
    corecore