CIMNE Verification of the validation analysis of Xfinas elements database

In order to validate the Xfinas code a very comprehensive series of test examples were solved by Prof Ki-Du Kim and his co-workers. A collection of the more representative benchmarks were chosen at CIMNE for testing the good behavior of every element implemented in the software. The aim of the validation work carried out at CIMNE has been to asses the accuracy of the Xfinas program. This was done studying the whole validation process carried out by Prof Ki-Du Kim’s team in detail. For this purpose we have chosen at CIMNE randomly the different benchmarks to be reproduced between those of the validation manual (VM from now on). In every example we checked the agreement of the results with the Xfinas validation data

Advancing the Boundaries of Formal Argumentation: Reflections on the AI3 2021 Special Issue

This article reflects on the Special Issue based on invited papers from the 5th Workshop on Advances in Argumentation in Artificial Intelligence (AI3 2021), showcasing the latest advancements in the field made by the Italian community on argumentation, as well as other researchers worldwide. This Special Issue highlights the importance of advancing logical-based AI approaches, such as formal argumentation, in the continuously expanding landscape of Artificial In- telligence. Papers in this Special Issue cover a diverse range of topics, including argument game-based proof theories, analysis of legal cases, decomposability in abstract argumentation, meta-argumentation approaches, explanations for model outputs using causal models, representation of natural argumentative discourse, and Paraconsistent Weak Kleene logic-based belief revision. By em- phasizing these innovative research contributions, this article underscores the need for continued progress in the field of Formal Argumentation to complement and enhance the ongoing developments in AI

A coupled Eulerian-Pfem model for the simulation of overtropping in rockfill dams

Rockfill dams are nowadays often preferred over concrete dams because of their economic advantages, their flexible and thank to the great advance achieved in geosciences and geomechanics. Unfortunately their behavior in case of overtopping is still an open issue. In fact very little is known on this phenomenon that in most cases leads to the complete finite failure o the structure with catastrophic consequences in term of loss of lives and economic damage. The principal aim of the present work is the development of a computational method to simulate the overtopping and the beginning of failure of the downstream shoulder of a rockfill dam. The whole phenomenon is treated in a continuous framework. The fluid free surface problem outside and inside the rockfill slop e is treated using a unique Eulerian fixed mesh formulation. A level set technique is employed to track the evolution of the free surface. The traditional Navier-Stokes equations are modified in order to automatically detect the presence of the porous media. The non-linear seepage is evaluated using a quadratic form of the resistance law for which the Ergun's coefficients have been chosen. &nbsp

A modified Finite Element formulation for the imposition of the slip boundary condition over embedded volumeless geometries

This work describes a novel formulation for the simulation of Navier-Stokes problems including embedded objects. The new proposal is based on the use of a modified finite element space, which replaces the standard one within the elements intersected by the immersed geometry. The modified space is able to exactly reproduce the jumps happening at the embedded boundary while preserving the conformity across the faces intersected by the embedded object. The paper focuses particularly on the imposition of a slip boundary condition on the surface of the embedded geometry, proposing a new technique for the application of such constraint. The new proposal is carefully benchmarked using the results of a body fitted technique and of an alternative embedded approach. Potential applications of interest are also presented

A stabilized mixed implicit Material Point Method for non-linear incompressible solid mechanics

In this work a stabilized mixed formulation for the solution of non-linear solid mechanics problems in nearly-incompressible conditions is presented. In order to deal with high material deformation, an implicit Material Point Method is chosen. Such choice allows avoiding the classical limitations of the Finite Element Method, e.g., element tangling and extreme mesh distortion. The proposed mixed formulation, with displacement and pressure as primary variables, is tested through classical benchmarks in solid and geo-mechanics where a Neo-Hookean, a J2 and a Mohr-Coulomb plastic law are employed. Further, the stabilized mixed formulation is compared with a displacement-based formulation to demonstrate how the proposed approach gets better results in terms of accuracy, not only when incompressible materials are simulated, but also in the case of compressible ones

Video display operator complaints: A 10-year follow-up of visual fatigue and refractive disorders

Visual fatigue and discomfort are very common complaints for video display operators (VDTs). The aim of our study was to study work-related visual symptoms in relation to refractive disorders and psychosocial factors in 3054 public employees by way of follow-ups for 10 years with periodic medical examinations with eye evaluation in the period 2000-2009. Factors related to visual fatigue were evaluated in the follow-up using generalized equation estimation. Visual fatigue was very common in VDT operators (64.03%). During the follow-up, no relationship between visual fatigue and age, sex, seniority of work, visual acuity and refractory disorders was found. Visual fatigue was significantly associated with anxiety perception in a dose-related matter (odds ratio (OR) 7.40, confidence interval (CI) 95% 1.77-31.3), psychosocial factors (OR 1.03, CI 95% 1.01-1.07), use of lenses (OR 1.34, CI 95% 1.09-1.64) and time of VDT usage (OR 1.27, CI 95% 1.04-1.53). This study confirmed that visual fatigue is common in VDT users and is related to anxiety perception, time of VDT usage, use of lenses and stress. No relationship was found between visual fatigue and refractory disorders or visual acuit

Landslide run-out simulations with depth-averaged models and integration with 3D impact analysis using the Material Point Method

Landslides pose a significant threat to human safety and the well-being of com- munities, making them one of the most challenging natural phenomena. Their potential for catastrophic consequences, both in terms of human lives and economic impact, is a major con- cern. Additionally, their inherent unpredictability adds to the complexity of managing the risks associated with landslides. It is crucial to continuously monitor areas susceptible to landslides. In situ detection systems like piezometers and strain gauges play a vital role in accurately mon- itoring internal pressures and surface movements in the targeted areas. Simultaneously, satel- lite surveys contribute by offering detailed topographic and elevation data for the study area. However, relying solely on empirical monitoring is insufficient for ensuring effective manage- ment of hazardous situations, especially in terms of preventive measures. This study provides advanced simulations of mudflows and fast landslides using particle depth-averaged methods, specifically employing the Material Point Method adapted for shallow water (Depth Averaged Material Point Method). The numerical method has been parallelized and validated through benchmark tests and real-world cases. Furthermore, the investigation extends to coupling the depth-averaged formulation with a three-dimensional one in order to have a detailed description of the impact phase of the sliding material on barriers and membranes. The multidimensional approach and its validation on real cases provide a robust foundation for a more profound and accurate understanding of the behavior of mudflows and fast landslides

Contact allergy to methylchloroisothiazolinone/methylisothiazolinone in north-eastern Italy: a temporal trend from 1996 to 2016

BACKGROUND: Methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI) (Kathon\uae CG) is a common preservative used in industrial products, owing to its strong biocide effect. Contact allergy to MCI/MI has been reported in different occupations, including mechanics, hairdressers and healthcare workers. OBJECTIVE: To retrospectively analyse the temporal trend of MCI/MI sensitization in north-eastern Italy and to evaluate the associations with occupations in our geographical area. METHODS: From 1996 to 2016, 27 381 patients with suspected allergic contact dermatitis were patch tested in eight departments of Dermatology or Occupational Medicine in north-eastern Italy. Individual characteristics were collected through a standardized questionnaire. RESULTS: The overall prevalence of MCI/MI sensitization was 4.2%, with the highest prevalence found in women and in patients younger than 25 years. MCI/MI sensitization was significantly associated with atopic eczema (OR: 1.34, 95% CI: 1.10-1.70), hand/forearm dermatitis (OR: 1.20, 95% CI: 1.05-1.36) and face dermatitis (OR 1.30, 95% CI: 1.10-1.40). There was a significant association between MCI/MI sensitization and chemical processing workers (OR 1.74, 95% CI: 1.03-2.94), while mechanics and healthcare workers resulted more sensitized to this hapten only in the last 3 years. CONCLUSIONS Sensitization to MCI/MI is rising in the last years in Triveneto region, the 'epidemic' of sensitization to MCI/MI is mainly driven by extra-occupational dermatitis, and sensitization in some occupational groups is emerging only in the last years. A full labelling is compulsory for all products that contain isothiazolinones, to permit to identify the culprit agent

Diaminodiphenylmethane Sensitization in north-eastern Italy from 1996 to 2012

BACKGROUND: 4,4'-Diaminodiphenylmethane (DDM) is an aromatic amine used as a hardener, insulator and anticorrosive. Exposure implies risk of being sensitized and developing contact dermatitis. OBJECTIVE: The aim of this study was to determine the occurrence of contact sensitization to DDM among patients with contact dermatitis and the role of occupational exposure. PATIENTS AND METHODS: From 1996 to 2012, 24 056 consecutive patients with suspected allergic contact dermatitis were patch tested in north-eastern Italy. Individual characteristics were collected through a standardized questionnaire in eight departments of dermatology and occupational medicine. RESULTS: The overall prevalence of DDM sensitization was 2.5% (n = 599) with a decreasing trend in considered years. Trieste area had the higher prevalence of sensitization (3.2%). Mechanics and chemical industry workers had a significant higher risk of being sensitized to DDM. CONCLUSION: DDM sensitization is decreasing in years and is associated with some occupational exposures

Hydraulic and stability analysis of the supporting layer of wedge-shaped blocks

Presented at the Protections 2016: 2nd international seminar on dam protection against overtopping: concrete dams, embankment dams, levees, tailings dams held on 7th-9th September, 2016, at Colorado State University in Fort Collins, Colorado, USA. The increasing demand for dam and levee safety and flood protection has motivated new research and advancements and a greater need for cost-effective measures in overtopping protection as a solution for overtopping concerns at levees and dams. This seminar will bring together leading experts from practice, research, development, and implementation for two days of knowledge exchange followed by a technical tour of the Colorado State University Hydraulic Laboratory with overtopping flume and wave simulator. This seminar will focus on: Critical issues related to levees and dams; New developments and advanced tools; Overtopping protection systems; System design and performance; Applications and innovative solutions; Case histories of overtopping events; Physical modeling techniques and recent studies; and Numerical modeling methods.Includes bibliographical references.Wedge shaped blocks (WSB) are attracting increasing attention as protection against overtopping for earth and rock-fill dams. However, there are limited examples of application and some aspects of the technology merit additional research and improvement. One key issue is the design of drainage and supporting layer for WSB protections. During overtopping, part of the overflow leaks through the joints between blocks, hence circulating through the granular material. The permeability and thickness of the supporting layer must be sufficient to prevent the flow from generating pressure on the bottom side of the blocks, which contributes to its destabilization. However, it must also be structurally stable to avoid undesirable deformations on the downstream face. Both the material permeability and the layer thickness determine the hydraulic behavior of this element. These, together with the weight of the blocks and the slope of the downstream face, directly influence mass and block stability. These aspects should be taken into account for the numerical modeling of seepage through the supporting layer. To this end, an application of the open source software Kratos Multi-physics was employed. A parametric study was conducted to quantify the influence of each design variable in the safety factor against mass sliding of the supporting and drainage layer