CONSTRUCTIVE AND PROBABILISTIC ANALYSIS OF EXCAVATED PILES WITH LOST METALLIC SHIRT

This work brings in its scope some analyzes around the constructive methodology of a case study that refers to the implantation of a dolphin (a structure that in this case has the purpose of mooring ships) at Pier III, located in Ponta da Madeira Maritime Terminal, in the city of São Luís, Maranhão, and with a focus on the process of building its infrastructure, more precisely the adopted foundation. This type of work, being port and in a maritime environment is called offshore, the foundation used in this case is the deep type, more precisely called piles excavated with a lost metallic shirt whose constructional scope will be detailed in this work, from the driving from shirts to concreting the piles that made up the system. The theme is approached from a practical and theoretical point of view, with a probabilistic study of the load capacity of foundations based on geometrical data from surveys carried out in the region, in order to define results that include any variability of the location and guarantee functionality and safety necessary for the foundation to achieve the project's objectives and be optimized throughout its useful life. The analysis of the probability of rupture was made using the semi-empirical method of Aoki-Velloso, combined with the First Order Second Moment method in order to compare the result achieved with the established parameter values. The work also aims to serve as a basis for future guidance and guidance on the topic, which does not have such a vast bibliography, mainly in view of the installation of new similar projects in the region and in other locations.

Mitral Valve Atlas for Artificial Intelligence Predictions of MitraClip Intervention Outcomes

Severe mitral regurgitation (MR) is a cardiac disease that can lead to fatal consequences. MitraClip (MC) intervention is a percutaneous procedure whereby the mitral valve (MV) leaflets are connected along the edge using MCs. The outcomes of the MC intervention are not known in advance, i.e., the outcomes are quite variable. Artificial intelligence (AI) can be used to guide the cardiologist in selecting optimal MC scenarios. In this study, we describe an atlas of shapes as well as different scenarios for MC implantation for such an AI analysis. We generated the MV geometrical data from three different sources. First, the patients' 3-dimensional echo images were used. The pixel data from six key points were obtained from three views of the echo images. Using PyGem, an open-source morphing library in Python, these coordinates were used to create the geometry by morphing a template geometry. Second, the dimensions of the MV, from the literature were used to create data. Third, we used machine learning methods, principal component analysis, and generative adversarial networks to generate more shapes. We used the finite element (FE) software ABAQUS to simulate smoothed particle hydrodynamics in different scenarios for MC intervention. The MR and stresses in the leaflets were post-processed. Our physics-based FE models simulated the outcomes of MC intervention for different scenarios. The MR and stresses in the leaflets were computed by the FE models for a single clip at different locations as well as two and three clips. Results from FE simulations showed that the location and number of MCs affect subsequent residual MR, and that leaflet stresses do not follow a simple pattern. Furthermore, FE models need several hours to provide the results, and they are not applicable for clinical usage where the predicted outcomes of MC therapy are needed in real-time. In this study, we generated the required dataset for the AI models which can provide the results in a matter of seconds.

Structural Design and Control of a Morphing Winglet to optimize the Aerodynamic Performance of the CRJ-700 Aircraft. Part 2 – Control

In this study, the morphing technology was applied on winglets for the CRJ-700 transport regional aircraft with the aim to improve its aerodynamic performance. The LARCASE Virtual Research Simulator VRESIM is equipped with highest Level D certified flight data for the CRJ-700. The flight and geometrical data of the CRJ-700 were used to quantify the aerodynamic benefits of the CRJ-700 equipped with a morphing winglet versus its reference winglet. The structural design and the mechanism allowing its rotation were used to allow the orientation of the winglet with angles between 90° and -90°. The control of the orientation of the morphing winglet with its mechanism was finally carried out using the Matlab/ Simulink interface. Therefore, a new concept of morphing winglet was obtained in this research.

Rock Mass Characterization by UAV and Close-Range Photogrammetry: A Multiscale Approach Applied along the Vallone dell’Elva Road (Italy)

Geostructural rock mass surveys and the collection of data related to discontinues provide the basis for the characterization of rock masses and the study of their stability conditions. This paper describes a multiscale approach that was carried out using both non-contact techniques and traditional support techniques to survey certain geometrical features of discontinuities, such as their orientation, spacing, and useful persistence. This information is useful in identifying the possible kinematics and stability conditions. These techniques are extremely useful in the case study of the Elva valley road (Northern Italy), in which instability phenomena are spread across 9 km in an overhanging rocky mass. A multiscale approach was applied, obtaining digital surface models (DSMs) at three different scales: large-scale DSM of the entire road, a medium-scale DSM to assess portions of the slope, and a small-scale DSM to assess single discontinuities. The georeferenced point cloud and consequent DSMs of the slopes were obtained using an unmanned aerial vehicle (UAV) and terrestrial photogrammetric technique, allowing topographic and rapid traditional geostructural surveys. This technique allowed us to take measurements along the entire road, obtaining geometrical data for the discontinuities that are statistically representative of the rock mass and useful in defining the possible kinematic mechanisms and volumes of potentially detachable blocks. The main purpose of this study was to analyse how the geostructural features of a rock mass can affect the stability slope conditions at different scales in order to identify road sectors susceptible to different potential failure mechanisms using only kinematic analysis.

VGI3D: an Interactive and Low-Cost Solution for 3D Building Modelling from Street-Level VGI Images

Applications in smart cities are inseparable from the usage of three-dimensional (3D) building models. However, the cost of generating and constructing 3D building models with semantic information is high both in time and in labour. To solve this problem, we developed a web-based interactive system, VGI3D, with the ambition of becoming a VGI platform to collect 3D building models with semantic information by using the power of crowdsourcing. VGI3D is a platform-independent software program that is composed of a spatially relational database (PostgreSQL/PostGIS) for the storage and management of spatially geometrical data and other software modules, allowing users to import, analyse, reconstruct, visualise, modify and export 3D building models according to the OBJ/CityGML standard. In this paper, we present the VGI3D in detail, focusing on relevant technical implementations, and report the results of limited usability testing aimed at optimising the system and user experience. After limited expert and non-expert participants’ testing, we proved the usefulness of VGI3D and its promising value for the 3D modelling community.

Validation of Aero-Load Estimator for Convair 880 Aircraft Flight Simulator Benchmark with Electro-Hydrostatic Actuators

Simulating an aircraft model using of high fidelity models of subsystems for its primary and secondary flight control actuators requires measuring or estimating aero-load data acting on flight control surfaces. One solution would be to incorporate the data recorded from flight tests, which is a time-consuming and costly process. This paper proposes another solution based on the validation of an aero-loads estimator or on the hinge moments predictor for fully electrical aircraft simulator benchmark. This estimator is based on an aerodynamic coefficient calculation methodology, inspired by Roskam’s method that uses the geometrical data of the wing and control surfaces airfoils. The hinge moment values are found from two-dimensional lookup tables where the deflections of the control surfaces, aircraft altitude, and aircraft angles of attack are the input vectors of the tables; and the resulting hinge moment coefficients are the output vectors. The resulting hinge moment coefficients of the Convair 880 primary flight control surfaces are compared to those of its recorded flight test data; the results from the new software solution were found to be very accurate. Hinge moment lookup tables are integrated in the Convair 880 high fidelity flight simulation benchmark using mathematical models of energy-efficient Electro-Hydrostatic Actuators (EHA). Autopilot controls are designed for the roll, pitch, attitude and yaw damper motions using Proportional Integral (PI) controller scheduled for different flight conditions. Several different aircraft simulation scenarios are evaluated to demonstrate the efficacy and accuracy of the predicted hinge moment results.

Segmentation of Change in Surface Geometry Analysis for Cultural Heritage Applications

This work proposes a change-based segmentation method for applications to cultural heritage (CH) imaging to perform monitoring and assess changes at each surface point. It can be used as a support or component of the 3D sensors to analyze surface geometry changes. In this research, we proposed a new method to identify surface changes employing segmentation based on 3D geometrical data acquired at different time intervals. The geometrical comparison was performed by calculating point-to-point Euclidean distances for each pair of surface points between the target and source geometry models. Four other methods for local distance measurement were proposed and tested. In the segmentation method, we analyze the local histograms of the distances between the measuring points of the source and target models. Then the parameters of these histograms are determined, and predefined classes are assigned to target surface points. The proposed methodology was evaluated by considering two different case studies of restoration issues on CH surfaces and monitoring them over time. The results were presented with a colormap visualization for each category of the detected change in the analysis. The proposed segmentation method will help in the field of conservation and restoration for the documentation and quantification of geometrical surface change information. This analysis can help in decision-making for the assessment of damage and potential prevention of further damage, and the interpretation of measurement results.

Is it Possible to Derive the Dresdner Correction Formula Using a Finite Element Program?

Introduction The aim was to construct a model cornea by CAD and finite element software to find out how the intraocular pressure compares to the forces for applanation at the outside of the model cornea. These data were to be compared to the Dresdner correction formula. Thereby, it was possible to find out whether the model was plausible and to find hints as to why a correction for how the intraocular pressure depends on the corneal thickness is necessary at all. Methods Using the open-source software FreeCad and geometrical data for the cornea of the literature, an average cornea was constructed. On this average cornea, a finite element analysis was performed using the free software z88aurora. The intraocular pressure was measured by applanation of the outer cornea. The necessary forces were analysed. Results In this model, the intraocular pressure had to be corrected depending on the corneal thickness. The correction factor was kmean; finite elements = 19.17 – 0.0334*corneal thickness. The necessary correction did not exclusively depend on the relation between the endothelial area and the area of the outer cornea: for this relation alone the correction would have been karea-relation = 1.0361 – 0.0006*corneal thickness. Discussion The model correction formula was close to the Dresdner formula. The relation between endothelial area and the area of the outer cornea could only explain about half of the necessary correction.

Mechanism of Actions of Dexamethasone against COVID-19 predicted by Alpha Shape Analysis of Binding Sites

Background: COVID-19 emerged in late 2019 and became a pandemic disease with severe mortality and morbidity. No specific remedy exists at present, but some drugs, such as Dexamethasone, have shown clinical benefits against the causative agent, the SARS-CoV-2 virus. Objective: To analyze the binding affinity between drugs and an SARS-CoV-2 protein through geometrical methods and to study the theoretical effectiveness of Dexamethasone as a potential treatment for COVID-19. Method: The binding affinity of Dexamethasone to the target SARS-CoV-2 protein was compared with those of different inhibitors. Drug molecules were docked to the SARS-CoV-2 main protease, and the system was simulated by molecular dynamics, allowing alpha shape analysis to extract geometrical features, such as the matching rates of atoms, solid angles, and the distances between atoms at interfaces. Binding affinities between drugs and the main protease were assessed by these geometrical data and the free energy of binding. Results: The behaviour of Dexamethasone was similar to other inhibitors. The efficacy of Dexamethasone as a treatment may be due to it being a glucocorticoid and its properties as a potent inhibitor. Conclusion: This study revealed the mechanism of action of Dexamethasone and provided a geometrical method to distinguish among potential drugs for the treatment of COVID-19.

BIM DESIGN LEAD FOR RESTORATION OF SHIPWRECK MUSEUM IN KYRENIA CASTLE IN CYPRUS

The paper deals with the application of Building Information Modelling (BIM) to the documentation and preservation of Archaeological Heritage. illustrating the implemantation process to a case study. The work process started from the historical analysis tighether with the geometric capturing of the built morphology. A 3D model was created by combining laser scans and a digital photogrammetric survey. To maka all 3D data sets interoperable, it was developed a BIM project execution plan focused on the restoration of Shipwreck Museum in the Kyrenia Castle in Cyprus. The HBIM approach not only allows ti represent the existing historic fabric with an effective visualization but also to lead a complex analysis of designed interventions in various scenarios. All the additional information besides the geometrical data were stored into the HBIM able ti document the manteinance and ti help the future works. It will be illustrated the procedure and the methodology by presenting the outcomes of the research.