The Architecture of Knowledge Testing Support System «Logit»

Показано варіант побудови інформаційної системи підтримки тестового контролю знань. Особливість підходу у відкритій моделі формування тесту, сплайн-моделі профілів та програмно-апаратній підтримці тестування. Очікуваним результатом є отримання інструментарію, який дасть можли-вість супроводжувати тест на всіх етапах його розробки, до створення за-кінченого інструменту для вимірювання знань.Представлен вариант построения информационной системы поддержки тестового контроля знаний. Особенность подхода в открытой модели формирования теста, сплайн-модели профилей и програмно-аппаратной поддержке тестирования. Ожидаемым результатом является получение инструментария, который позволит сопровождать тест на всех этапах его разработки, до создания законченного инструмента для измерения знаний.This paper presents a way of developing an information system to support the test control knowledge. Feature of the approach in an open model of the formation test, the spline model profiles, software and hardware support for testing. The expected result is to provide tools that will accompany the test at all stages of its development, to create a complete tool for measuring knowledge

Rapid Filling Analysis with an Entrapped Air Pocket in Water Pipelines Using a 3D CFD Model

A filling operation generates continuous changes over the shape of an air–water interface, which can be captured using a 3D CFD model. This research analyses the influence of different hydro-pneumatic tank pressures and air pocket sizes as initial conditions for studying rapid filling operations in a 7.6 m long PVC pipeline with an irregular profile, using the OpenFOAM software. The analysed scenarios were validated using experimental measurements, where the 3D CFD model was suitable for simulating them. In addition, a mesh sensitivity analysis was performed. Air pocket pressure patterns, water velocity oscillations, and the different shapes of the air–water interface were analysed

Different Experimental and Numerical Models to Analyse Emptying Processes in Pressurised Pipes with Trapped Air

In hydraulic engineering, some researchers have developed different mathematical and numerical tools for a better understanding of the physical interaction between water flow in pipes with trapped air during emptying processes, where they have made contributions on the use of simple and complex models in different application cases. In this article, a comparative study of different experimental and numerical models existing in the literature for the analysis of trapped air in pressurised pipelines subjected to different scenarios of emptying processes is presented, where different authors have develope, experimental, one-dimensional mathematical and complex computational fluid dynamics (CFD) models (two-dimensional and three-dimensional) to understand the level of applicability of these models in different hydraulic scenarios, from the physical and computational point of view. In general, experimental, mathematical and CFD models had maximum Reynolds numbers ranging from 2670 to 20,467, and it was possible to identify that the mathematical models offered relevant numerical information in a short simulation time on the order of seconds. However, there are restrictions to visualise some complex hydraulic and thermodynamic phenomena that CFD models are able to illustrate in detail with a numerical resolution similar to the mathematical models, and these require simulation times of hours or days. From this research, it was concluded that the knowledge of the information offered by the different models can be useful to hydraulic engineers to identify physical and numerical elements present in the air–water interaction and computational conditions necessary for the development of models that help decision-making in the field of hydraulics of pressurised pipelines

Three-dimensional simulation of transient flows during the emptying of pipes with entrapped air

Two-and three-dimensional analyses of transient flows considering the air-water interaction have been a challenge for researchers due to the complexity in the numerical resolution of the multiphase during emptying in pressurized water pipelines. The air-water dynamic interaction of emptying processes can be analyzed using thermodynamic and hydraulic laws. There is a lack in the current literature regarding the analysis of those phenomena using 3D models. In this research, several simulations were performed to study the complex details of two-phase flows. A 3D model was proposed to represent the emptying process in a single pipeline, considering a PVoF model and two-equation turbulence model. The model was numerically validated through 12 experimental tests and mesh sensitivity analysis. The pressure pulses of the air pockets were evaluated and compared with the experimental results and existing mathematical models, showing how the 3D models are useful for capturing more detailed information, such as pressure and velocity patterns of discrete air pockets, distribution of air and water velocity contours, and the exploration of temperature changes for an air pocket expansion

Three-dimensional analysis of air-admission orifices in pipelines during hydraulic drainage events

[EN] Air valves operate as protection devices in pipelines during drainage processes in order to mitigate vacuum pressures and control the transient flows. Currently, different authors have proposed one-dimensional models to predict the behaviour of orifices during filling and draining events, which offer good numerical results. However, the three-dimensional dynamic behaviour of air-admission orifices during drainage processes has not been studied in depth in the literature. In this research, the effects of air inflow on an orifice installed in a single pipe during drainage events are analysed using a three-dimensional computational fluid dynamics model by testing orifices with diameters of 1.5 and 3.0 mm. This model was validated with different experimental measurements associated to the vacuum pressure, obtaining good fits. The three-dimensional model predicts additional information associated to the aerodynamic effects that occur during the air-admission processes, which is studied. Subsonic flows are observed in different orifices with Mach numbers between 0.18 and 0.30. In addition, it is shown that the larger-diameter orifice ensures a more effective airflow control compared to the smaller-diameter orifice.This research was funded by grant No. INV03CI2214 of the Universidad Tecnologica de Bolivar.Paternina-Verona, DA.; Coronado-Hernández, OE.; Espinoza-Román, HG.; Besharat, M.; Fuertes-Miquel, VS.; Ramos, HM. (2022). Three-dimensional analysis of air-admission orifices in pipelines during hydraulic drainage events. Sustainability. 14(21):1-14. https://doi.org/10.3390/su142114600114142

Effects of orifice sizes for uncontrolled filling processes in water pipelines

The sizing of air valves during the air expulsion phase in rapid filling processes is crucial for design purposes. Mathematical models have been developed to simulate the behaviour of air valves during filling processes for air expulsion, utilising 1D and 2D schemes. These transient events involve the presence of two fluids with different properties and behaviours (water and air). The effect of air valves under scenarios of controlled filling processes has been studied by various authors; however, the analysis of uncontrolled filling processes using air valves has not yet been considered. In this scenario, water columns reach high velocities, causing part of them to close air valves, which generates an additional peak in air pocket pressure patterns. In this research, a two-dimensional computational fluid dynamics model is developed in OpenFOAM software to simulate the studied situations

Improving Pump Characteristics through Double Curvature Impellers: Experimental Measurements and 3D CFD Analysis

The outlet angle and shape of impeller blades are important parameters in centrifugal pump design. There is a lack of detailed studies related to double curvature impellers in centrifugal pumps in the current literature; therefore, an experimental and numerical analysis of double curvature impellers was performed. Six impellers were made and then assessed in a centrifugal pump test bed and simulated via 3D CFD simulation. The original impeller was also tested and simulated. One of the manufactured impellers had the same design as the original, and the other five impellers had a double curvature. Laboratory tests and simulations were conducted with three rotation speeds: 1400, 1700, and 1900 RPM. Head and performance curve equations were obtained for the pump–engine unit based on the flow of each impeller for the three rotation speeds. The results showed that a double curvature impeller improved pump head by approximately 1 m for the range of the study and performance by about 2% when compared to basic impeller. On the other hand, it was observed that turbulence models such as k-e and SST k-w reproduced similar physical and numerical results

Effects of Orifice Sizes for Uncontrolled Filling Processes in Water Pipelines

[EN] The sizing of air valves during the air expulsion phase in rapid filling processes is crucial for design purposes. Mathematical models have been developed to simulate the behaviour of air valves during filling processes for air expulsion, utilising 1D and 2D schemes. These transient events involve the presence of two fluids with different properties and behaviours (water and air). The effect of air valves under scenarios of controlled filling processes has been studied by various authors; however, the analysis of uncontrolled filling processes using air valves has not yet been considered. In this scenario, water columns reach high velocities, causing part of them to close air valves, which generates an additional peak in air pocket pressure patterns. In this research, a two-dimensional computational fluid dynamics model is developed in OpenFOAM software to simulate the studied situations.Aguirre-Mendoza, AM.; Paternina-Verona, DA.; Oyuela, S.; Coronado-Hernández, OE.; Besharat, M.; Fuertes-Miquel, VS.; Iglesias Rey, PL.... (2022). Effects of Orifice Sizes for Uncontrolled Filling Processes in Water Pipelines. Water. 14(6):1-11. https://doi.org/10.3390/w1406088811114

Serological proteome analysis reveals new specific biases in the IgM and IgG autoantibody repertoires in autoimmune polyendocrine syndrome type 1

Objective: Autoimmune polyendocrine syndrome type 1 (APS 1) is caused by mutations in the AIRE gene that induce intrathymic T-cell tolerance breakdown, which results in tissue-specific autoimmune diseases. Design: To evaluate the effect of a well-defined T-cell repertoire impairment on humoral self-reactive fingerprints, comparative serum self-IgG and self-IgM reactivities were analyzed using both one- and two-dimensional western blotting approaches against a broad spectrum of peripheral tissue antigens. Methods: Autoantibody patterns of APS 1 patients were compared with those of subjects affected by other autoimmune endocrinopathies (OAE) and healthy controls. Results: Using a Chi-square test, significant changes in the Ab repertoire were found when intergroup patterns were compared. A singular distortion of both serum self-IgG and self-IgM repertoires was noted in APS 1 patients. The molecular characterization of these antigenic targets was conducted using a proteomic approach. In this context, autoantibodies recognized more significantly either tissue-specific antigens, such as pancreatic amylase, pancreatic triacylglycerol lipase and pancreatic regenerating protein 1α, or widely distributed antigens, such as peroxiredoxin-2, heat shock cognate 71-kDa protein and aldose reductase. As expected, a well-defined self-reactive T-cell repertoire impairment, as described in APS 1 patients, affected the tissue-specific self-IgG repertoire. Interestingly, discriminant IgM reactivities targeting both tissue-specific and more widely expressed antigens were also specifically observed in APS 1 patients. Using recombinant targets, we observed that post translational modifications of these specific antigens impacted upon their recognition. Conclusions: The data suggest that T-cell-dependent but also T-cell-independent mechanisms are involved in the dynamic evolution of autoimmunity in APS 1

Polymer "ruthenium-cyclopentadienyl" conjugates - New emerging anti-cancer drugs

In this work, we aimed to understand the biological activity and the mechanism of action of three polymer-'ruthenium-cyclopentadienyl' conjugates (RuPMC) and a low molecular weight parental compound (Ru1) in cancer cells. Several biological assays were performed in ovarian (A2780) and breast (MCF7, MDA-MB-231) human cancer derived cell lines as well as in A2780cis, a cisplatin resistant cancer cell line. Our results show that all compounds have high activity towards cancer cells with low IC50 values in the micromolar range. We observed that all Ru-PMC compounds are mainly found inside the cells, in contrast with the parental low molecular weight compound Ru1 that was mainly found at the membrane. All compounds induced mitochondrial alterations. PMC3 and Ru1 caused F-actin cytoskeleton morphology changes and reduced the clonogenic ability of the cells. The conjugate PMC3 induced apoptosis at low concentrations comparing to cisplatin and could overcame the platinum resistance of A2780cis cancer cells. A proteomic analysis showed that these compounds induce alterations in several cellular proteins which are related to the phenotypic disorders induced by them.Our results suggest that PMC3 is foreseen as a lead candidate to future studies and acting through a different mechanism of action than cisplatin. Here we established the potential of these Ru compounds as new metallodrugs for cancer chemotherapy.This work was financed by the Portuguese Foundation for Science and Technology (Fundacao para a Ciencia e a Tecnologia, FCT) within the scope of projects UID/QUI/00100/2013 and PTDC/QUI-QIN/28662/2017. This work was supported by the strategic program UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) funded by national funds through the FCT I.P. and by the ERDF through the COMPETE2020 - Programa Operacional Competitividade e Internacionalizacao (POCI). Andreia Valente acknowledges the COST action CM1302 (SIPs), the Investigator FCT2013 Initiative for the project IF/01302/2013 (acknowledging FCT, as well as POPH and FSE - European Social Fund) and the Royal Society of Chemistry's Research Fund. Pierre Falson and Elisabeta Comsa warmly acknowledge Thibault Andrieu from the cytometry plateau of SFR bioscience -UMS 3444- at Lyon-Gerland, France for assistance on CytoF. This work was also supported by the Marie Curie Initial Training Network: FP7-PEOPLE-2012-ITN proposal no 317297 - acronym GLYCOPHARM and PITN-GA-2012-317297. The high resolution mass spectrometer at CIRE-PAIB was financed (SMHART project no3069) by the European Regional Development Fund (ERDF), the Conseil Regional du Centre, the French National Institute for Agricultural Research (INRA) and the French National Institute of Health and Medical Research (Inserm)