Research on the Friction Properties of DP600 Stainless Steel as a Function of Bending Angle and Pin Diameter

[EN] The rapid evolution of materials and manufacturing processes, driven by global competition and new safety and environmental regulations has had an impact on automotive structures (Body In White; BIW) manufacturing. The need for lighter vehicles, with more equipment, that are safer and eco-friendly at the same time, relates to the entire life cycle of the car. Car and steelmakers agree that weight reduction is possible, and the solution involves the use of new advanced high-strength steels. Thinner and stronger materials lead to higher demands on stamping, the most used manufacturing in BIW parts. The use of advanced high-strength steels raises new challenges, especially concerning the lubrication between the die and the sheet. To study the lubrication conditions of the stamping process, a sheet metal forming a simulator was developed. The simulator consists of two cylinders that pull the strip of steel and a pin in between. The angle between the cylinders can be adjusted from 0 to 90 degrees, which allows analysis of the effect of the stamping angle. The pull force and velocity can be set and measured, and the peripheric pin velocity, the strain, and the strain velocity can be measured as well. In this work, the tribological properties of Dual-Phase 600 stainless steel using different processing conditions have been analyzed. To this end, a factorial experiments design with twelve parameters that compare the behavior of different angles and diameters was run. The results showed that the friction coefficient increases by increasing the bending angle and decreases with pin diameter.Sanchez-Caballero, S.; Sellés, M.; Pla-Ferrando, R.; Segui Llinares, VJ.; Peydro, MA. (2021). Research on the Friction Properties of DP600 Stainless Steel as a Function of Bending Angle and Pin Diameter. Materials Proceedings. 3(1):1-7. https://doi.org/10.3390/IEC2M-09248173

Validity of a self-reported diagnosis of depression among participants in a cohort study using the Structured Clinical Interview for DSM-IV (SCID-I).

Abstract Background: Depression assessment in population studies is usually based on depressive symptoms scales. However, the use of scales could lead to the choice of an arbitrary cut-off point depending on the sample characteristics and on the patient diagnosis. Thus, the use of a medical diagnosis of depression could be a more appropriate approach. Objective: To validate a self-reported physician diagnosis of depression using the Structured Clinical Interview for DSM-IV (SCID-I) as Gold Standard and to assess the factors associated to a valid self-reported diagnosis. Methods: The SUN Project is a cohort study based on university graduates followed-up through postal questionnaires. The response to the question included in the questionnaire: Have you ever been diagnosed of depression by a physician? was compared to that obtained through the SCID-I applied by a psychiatrist or a clinical psychologist. The percentages of confirmed depression and non-depression were assessed for the overall sample and according to several characteristics. Logistic regression models were fitted to ascertain the association between different factors and a correct classification regarding depression status. Results: The percentage of confirmed depression was 74.2%; 95% confidence interval (95% CI) =63.3-85.1. Out of 42 participants who did not report a depression diagnosis in the questionnaire, 34 were free of the disease (%confirmed non-depression=81.1%; 95% CI=69.1- 92.9). The probability of being a true positive was higher among ex- smokers and non-smokers and among those overweight or obese but the differences were not statistically significant. Conclusion: The validity of a self-reported diagnosis of depression in the SUN cohort is adequate. Thus, this question about depression diagnosis could be used in further investigations regarding this disease in this graduate cohort study

Study of the mechanical properties of recycled abs and recovery throught mixing with SEBS

Recovery of recycled acrylonitrile butadiene styrene (ABS) through mixing with styrene-ethylene/butylene- styrene (SEBS) has been studied in this paper. To simulate recycled ABS, virgin ABS was processed through 5 cycles, at extreme processing temperatures, 220 oC and 260 oC. The virgin ABS, the virgin SEBS, the recycled ABS and the mixtures were mechanically characterized after the various cycles of reprocessing in order to evaluate their corresponding properties and correlate them with the number of cycles undergone. The results show that tensile strength of ABS remains practically constant as the number of reprocessing cycles increases, while in the material injected with SEBS the tensile strength decreases. Concerning the Charpy notched impact strength; the values of the ABS reprocessed at 220 oC remain more or less unchanged, while the values for 260 oC show a significant decrease. The adhesion of the SEBS causes, in both cases, an increase in impact strength.Peydro, MA.; Juárez Varón, D.; Sanchez-Caballero, S.; Pla-Ferrando, R. (2014). Study of the mechanical properties of recycled abs and recovery throught mixing with SEBS. Annals of The University of Oradea. Fascicle of Management and Technological Engineering. (1):83-86. http://hdl.handle.net/10251/57748S8386

Gear train optimization using evolutionary algorithms

[EN] This paper shows a genetic algorithm (GA)-based optimization procedure for gear trains design. Gear design uses simultaneous discrete (P.E. pitch) and continuous variables nonlinearly related. However, unlike GAs, most optimization methods are only suited for continuous design variables. This paper uses GAs as a tool to achieve not only the optimal design, but also a series of near-optimal designs. To achieve this objective, first the optimization problem is formulated. It must be multiobjective (maximum strength, minimum energetic losses, etc) and restricted. A mechanism to transform the constrained problem into unconstrained thought penalty functions is proposed. Recommendations on the objective function and penalty terms are also suggested. Next a design variables coding and decoding method, as well the genetic operators of reproduction, crossover and mutation are presented. Finally, it is analyzed an example in which the developed genetic algorithm has been used, comparing the obtained results from a previous optimization.[ES] En el presente artículo se expone un procedimiento de diseño de transmisiones de engranajes basado en los Algoritmos Genéticos (GA). En el diseño de engranajes se emplean simultáneamente variables continuas y discretas (p.e. el paso) relacionadas entre sí de forma no lineal. Sin embargo, a diferencia de los GAs, la mayoría de métodos de optimización sólo funcionan adecuadamente con variables de diseño continuas. El presente trabajo emplea los GAs como una herramienta que nos permita encontrar no sólo un diseño óptimo, sino también un conjunto de diseños cercanos al mismo. Para lograr este objetivo, en primer lugar se formula el problema de optimización. Este debe ser multiobjetivo (máxima resistencia, mínimas pérdidas energéticas, etc.) y restringido, proponiéndose un mecanismo para transformar el problema restringido en no restringido mediante el empleo de funciones de penalización. También se proponen recomendaciones sobre la elección de la función objetivo y los términos de penalización de la misma. Seguidamente se plantea el método de codificación y decodificación de las variables de diseño, así como los operadores génicos de reproducción, cruce y mutación. Finalmente se analiza un ejemplo en el que se implementa el algoritmo genético expuesto, comparando los resultados con los obtenidos en una optimización previa.Sanchez-Caballero, S.; Sellés Cantó, MÁ.; Peydro, MA.; Pla-Ferrando, R. (2013). Optimización de transmisiones de engranajes mediante algoritmos evolutivos. 3c Tecnologia. (7):1-17. http://hdl.handle.net/10251/36305S117

Nuevas técnicas de optimización de estructuras

La optimización de estructuras ha sido objeto de un intenso estudio durante los últimos cincuenta años. Aunque la Programación Matemática fue inicialmente la técnica más empleada, ha sido reemplazada por un conjunto de técnicas meta heurísticas. Entre ellas los Algoritmos Genéticos es la técnica más importante. Este trabajo realiza una pequeña descripción de cada una de estas así como sus principales trabajos e inconvenientes. Finalmente, se analiza la estructura más empleada como banco de pruebas para posteriormente mostrar y comentar los mejores resultados obtenidos hasta la fecha.Sanchez-Caballero, S.; Sellés Cantó, MÁ.; Pla-Ferrando, R.; Peydro, MA. (2012). Nuevas técnicas de optimización de estructuras. 3C Tecnología. 1(3):1-19. http://hdl.handle.net/10251/30123S1191

Biomimetic Citrate-Coated Luminescent Apatite Nanoplatforms for Diclofenac Delivery in Inflammatory Environments

Luminescent nanoparticles are innovative tools for medicine, allowing the imaging of cells and tissues, and, at the same time, carrying and releasing different types of molecules. We explored and compared the loading/release ability of diclofenac (COX-2 antagonist), in both undoped-and luminescent Terbium3+ (Tb3+)-doped citrate-coated carbonated apatite nanoparticles at different temperatures (25, 37, 40 °C) and pHs (7.4, 5.2). The cytocompatibility was evaluated on two osteosarcoma cell lines and primary human osteoblasts. Biological effects of diclofenac-loadednanoparticles were monitored in an in vitro osteoblast’s cytokine–induced inflammation model by evaluating COX-2 mRNA expression and production of PGE2. Adsorption isotherms fitted the multilayer Langmuir-Freundlich model. The maximum adsorbed amounts at 37 °C were higher than at 25 °C, and particularly when using the Tb3+-doped particles. Diclofenac-release efficiencies were higher at pH 5.2, a condition simulating a local inflammation. The luminescence properties of diclofenac-loaded Tb3+-doped particles were affected by pH, being the relative luminescence intensity higher at pH 5.2 and the luminescence lifetime higher at pH 7.4, but not influenced either by the temperature or by the diclofenac-loaded amount. Both undoped and Tb3+-doped nanoparticles were cytocompatible. In addition, diclofenac release increased COX-2 expression and decreased PGE2 production in an in vitro inflammation model. These findings evidence the potential of these nanoparticles for osteo-localized delivery of anti-inflammatory drugs and the possibility to localize the inflammation, characterized by a decrease in pH, by changes in luminescence

A schizophrenia-like psychotic disorder secondary to an arachnoid cyst remitted with neurosurgical treatment of the cyst

We describe a case of delusional psychosis that was terminated by neurosurgical removal of a large arachnoid cyst. The patient was suffering his first psychotic episode and had symptoms typical of schizophrenia. The case underscores the importance of considering that an arachnoid cyst can induce psychopathological symptoms, even those of schizophrenia. Indeed, such symptoms may be the cyst's only clinical manifestation. In addition, the case highlights the importance of doing a structural imaging test when confronted with a first episode of psychosis, especially if the episode is relatively late in appearance. Such imaging may lead to a diagnosis that in turn can enable a definitive neurosurgical resolution of the psychosis

Tools for BIM-GIS integration (IFC georeferencing and conversions): Results from the GeoBIM benchmark 2019

The integration of 3D city models with Building Information Models (BIM), coined as GeoBIM, facilitates improved data support to several applications, e.g., 3D map updates, building permits issuing, detailed city analysis, infrastructure design, context-based building design, to name a few. To solve the integration, several issues need to be tackled and solved, i.e., harmonization of features, interoperability, format conversions, integration of procedures. The GeoBIM benchmark 2019, funded by ISPRS and EuroSDR, evaluated the state of implementation of tools addressing some of those issues. In particular, in the part of the benchmark described in this paper, the application of georeferencing to Industry Foundation Classes (IFC) models and making consistent conversions between 3D city models and BIM are investigated, considering the OGC CityGML and buildingSMART IFC as reference standards. In the benchmark, sample datasets in the two reference standards were provided. External volunteers were asked to describe and test georeferencing procedures for IFC models and conversion tools between CityGML and IFC. From the analysis of the delivered answers and processed datasets, it was possible to notice that while there are tools and procedures available to support georeferencing and data conversion, comprehensive definition of the requirements, clear rules to perform such two tasks, as well as solid technological solutions implementing them, are still lacking in functionalities. Those specific issues can be a sensible starting point for planning the next GeoBIM integration agendas

Review of current Severe Accident Management (SAM) approaches for Nuclear Power Plants in Europe

The Fukushima accidents highlighted that both the in-depth understanding of such sequences and the development or improvement of adequate Severe Accident Management (SAM) measures are essential in order to further increase the safety of the nuclear power plants operated in Europe. To support this effort, the CESAM (Code for European Severe Accident Management) R&D project, coordinated by GRS, started in April 2013 for 4 years in the 7th EC Framework Programme of research and development of the European Commission. It gathers 18 partners from 12 countries: IRSN, AREVA NP SAS and EDF (France), GRS, KIT, USTUTT and RUB (Germany), CIEMAT (Spain), ENEA (Italy), VUJE and IVS (Slovakia), LEI (Lithuania), NUBIKI (Hungary), INRNE (Bulgaria), JSI (Slovenia), VTT (Finland), PSI (Switzerland), BARC (India) plus the European Commission Joint Research Center (JRC). The CESAM project focuses on the improvement of the ASTEC (Accident Source Term Evaluation Code) computer code. ASTEC,, jointly developed by IRSN and GRS, is considered as the European reference code since it capitalizes knowledge from the European R&D on the domain. The project aims at its enhancement and extension for use in severe accident management (SAM) analysis of the nuclear power plants (NPP) of Generation II-III presently under operation or foreseen in near future in Europe, spent fuel pools included. In the frame of the CESAM project one of the tasks consisted in the preparation of a report providing an overview of the Severe Accident Management (SAM) approaches in European Nuclear Power Plants to serve as a basis for further ASTEC improvements. This report draws on the experience in several countries from introducing SAMGs and on substantial information that has become available within the EU “stress test”. To disseminate this information to a broader audience, the initial CESAM report has been revised to include only public available information. This work has been done with the agreement and in collaboration with all the CESAM project partners. The result of this work is presented here.JRC.F.5-Nuclear Reactor Safety Assessmen