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Evaluating the unavailability of interconnected power and communication networks with open-source tools on a petascale cluster
No full textIn reliability engineering, unavailability is defined as the probability that a system is not operational at a given point in time, typically due to failure or maintenance. A critical gap in reliability analysis by systematically evaluating the time-dependent unavailability of real interconnected power and communication networks in the Czech Republic is addressed in this work. These networks are modelled as acyclic graphs using open-source R packages. Unlike previous studies relying on commercial tools, the research presented here offers a novel, reproducible, and scalable framework. The main contribution lies in the innovative application and benchmarking of ftaproxim, an R package based on proxel simulation, which models ageing components during their entire life using various probabilistic distributions. This approach contrasts with traditional tools such as the FaultTree package, which are limited to asymptotic unavailability analysis. Here presented work evaluates both R packages on a real infrastructure model and compares their performance and computational efficiency on the Barbora supercomputer cluster against commercial software (Matlab). It is demonstrated how ftaproxim’s tolerance and time-step parameters can be tuned for robust computational efficiency and accuracy, an aspect previously unexplored. The results of the presented study show that unavailability computations can be completed in approximately 5 h under optimal settings, with absolute errors ranging from 1.0× 10−4to 9.6× 10−4when compared to commercial solutions. This integrated approach, combining open-source tools, high
Computational Study of Nozzle Configuration Effects on Heat Transfer and Flow Characteristics in Aero-Engine Swirling Anti-Icing Systems
No full textEngine inlet icing persists as a critical hazard to aviation operational safety, compromising aerodynamic performance and potentially inducing catastrophic engine failure. Aero-engine swirling anti-icing systems inject high-temperature bleed air into an annular chamber at the engine’s leading edge through tangentially positioned nozzles. This high-velocity jet entrains low-temperature air within the chamber, establishing a circulatory flow that effectively heats the lip surface to prevent ice formation. This study employs computational fluid dynamics (CFD) method to systematically evaluate the flow and heat transfer characteristics of four distinct nozzle configurations within an aero-engine anti-icing chamber: conical single-orifice, diffuser-equipped, elliptical dual-orifice, and elliptical quad-orifice nozzles. Results indicate that the conical single-orifice nozzle exhibits the highest entrainment efficiency due to its concentrated jet structure, whereas the diffuser-equipped nozzle demonstrates 16.4%– 18.1% lower efficiency, attributable to premature kinetic energy dissipation. At identical bleed air flow rates, the diffuser-equipped nozzle yields the lowest circulation velocity and pressure loss, necessitating minimal bleed air pressure. The elliptical quad-orifice nozzle optimally mitigates hot and cold spots via multi-jet energy dispersion, achieving a maximum 34.7% reduction in lip surface temperature differentials compared to the conical single-orifice design within the analyzed bleed air mass flow rate range. Nozzle configurations exert limited influence on the average Nusselt number, with a maximum relative deviation of 5.48% observed across all nozzle configurations when compared to established empirical correlations.OPEN ACCESS Received: 11/07/2025 Accepted: 21/08/2025 Published: 15/12/202
COL·LABORACIÓ EMPRESARIAL PUBLICOPRIVADA EN LA TRANSFORMACIÓ URBANA DE GRANS CIUTATS EUROPEES: EL DISTRICTE DE CIUTAT VELLA A BARCELONA (1988-2002)
No full textAquesta comunicació analitza l’impacte dels acords de col·laboració publicoprivats en els processos de renovació de grans ciutats europees postindustrials durant l'últim quart del segle XX, mitjançant l’estudi de cas del districte de Ciutat Vella, Barcelona. S'examina la gestió de PROCIVESA (Promoció de Ciutat Vella S.A; 1988-2002), una companyia mixta pionera al sud d’Europa en la transformació socioeconòmica i física d’àrees urbanes greument deteriorades. A través d’una metodologia qualitativa i marcs teòrics propis de la Història Econòmica i Empresarial, s’avalua la trajectòria de l'empresa durant els catorze anys d’activitat, destacant els èxits, els reptes i els efectes de les seves intervencions sobre un teixit urbà viu. Aquest estudi contribueix, des d'un àmbit local, als debats acadèmics internacionals sobre l'aplicació de figures organitzacionals creatives i innovadores, com la col·laboració publicoprivada, per a la resolució de problemes urbans en contextos d’alta complexitat
Catalan Long-Term Care system reaches the majority of age: What have we learned?
Get PDFAlmost 20% of the Catalan population is aged 65 years or older. By 2050, this percentage is estimated to reach 29%. In addition, this population cohort is associated with the longest life expectancy among OECD countries, yet only half of the total life expectancy at 65 is expected to be healthy life expectancy (OECD, 2024). Far from healthy ageing, in 2021, around 66% of the Spanish elderly do not self-rate their health as good or very good, and 49% report limitations in carrying out activities of daily living. In this context, the Long-Term Care (LTC) system—representing the fourth pillar of the welfare state—is being consolidated, reaching the majority of age. The first goal of this communication is to present the main features of the system and compare and contrast it with European counterparts. Secondly, we aim to provide the main insights learned from a diverse range of system’s analyses. With respect to the financial sustainability of the Spanish LTCS, underfunding and suboptimal design has increased the burden on families through higher co-payments. Despite this limited capacity, it has been remarked on the significant economic impact through job creation. Regarding the effects of Spanish LTCS on beneficiaries and their families, the introduction of Spanish LTC has reduced hospitalizations, primarily driven by conditions that could be avoided if LTC is adequately provided. In addition, LTC benefits have reduced the level of savings, increased the supply of informal caregivers, caregivers’ wellbeing and the probability of early retirement among caregivers. Last but not least, research has also analysed the implementation and design of Spanish LTC. While navigating the system is not associated with socioeconomic horizontal inequity, access to different types of benefits (and their mode of provision) shows evidence of socioeconomic horizontal inequity. Furthermore, the COVID-19 pandemic has highlighted critical weaknesses in nursing home care, including underfunding and inadequate staffing, which have contributed to high fatality rate
Validation of the AI-Readiness and Market Dynamics Disruption Index (AIM-DDI) Framework: A Case Study of Its Application in the Beauty Cluster
Get PDFThe adoption of artificial intelligence (AI) is transforming and disrupting industries by driving innovation, enhancing operational efficiency, and reshaping market dynamics. However, organizations often struggle to balance internal readiness with external market alignment, creating a critical need for comprehensive frameworks to guide AI integration. This study introduces and validates the AI-Readiness and Market Dynamics Disruption Index (AIM-DDI), a holistic tool for evaluating organizational AI maturity. By combining internal factors, such as strategy, talent, and governance, with external elements, including customer expectations, industry disruption potential, and regulatory environments, the AIM-DDI provides actionable insights for navigating AI-driven transformation. The research validates the AIM-DDI scale and questionnaire, leveraging data from 765 organizations to identify distinct AI maturity profiles. Cronbach’s Alpha Analysis , Exploratory and Confirmatory Factor Analyses confirm the framework’s validity, while cluster analysis reveals strategic pathways for organizations at various stages of AI readiness. The findings highlight the importance of aligning internal capabilities with external pressures to achieve competitive advantage and sustainable growth. We also apply the AIM-DDI framework within the Beauty Clusters Industry Association in Spain data as business case. This study offers valuable contributions for academics, practitioners, and policymakers aiming to leverage AI as a driver of industry evolution
Sistemas de Gestión de la Calidad.
No full textEsta comunicación pretende dar a conocer la Norma Internacional de Gestión de la Calidad 1 (NIGC1-ES), su evolución desde la Norma Internacional de Control de Calidad 1, su relación con algunos aspectos de la regulación de Prevención de Blanqueo de Capitales y Financiación del Terrorismo y, fundamentalmente, los paralelismos entre la NIGC1 y la norma UNE-EN ISO 9001, de aplicación en cualquier tipo de organización.
Los foros internacionales que han desarrollado dichas normas con el objetivo común de proporcionar confianza en la actividad y outputs de las organizaciones que las aplican, no pueden ser, no obstante, más dispares: las normas ISO se gestan en los comités de trabajo de la International Organization for Standarization que les presta sus siglas, mientras que las normativas para la firmas de auditoría son publicadas por la IFAC (International Federation of Accountants) y desarrolladas en el seno del IAASB (International Auditing and Assurance Standards Board)
Research on Master Production Schedule Optimization of Fast-Moving Consumer Goods Companies Based on the APO-NSAGA Algorithm
Get PDFThis study addresses several issues related to the Master Production Schedule (MPS) in companies, such as over-reliance on manual scheduling by planners, failure to consider the overall perspective of the company, lack of consideration for the impact of seasonal demand fluctuations on the MPS, overlooking potential losses due to stockouts and the resulting loss of market share, inability to adjust the MPS in a timely manner to respond to complex and rapidly changing market demands, and the suboptimal outcomes of the manually compiled production plans. To address these problems, an MPS model is established with the goals of optimizing equipment utilization balance, production costs, inventory costs, and delay costs while comprehensively considering the annual product demand. Subsequently, the artificial protozoan optimization nondominated sorting adaptive genetic algorithm (APO-NSAGA) is developed based on the artificial protozoan optimization (APO) and the non-dominated sorting genetic algorithm (NSGA-II). In this algorithm, autotrophic, heterotrophic, and dormancy behaviors are used to enhance the local search capability and guide the algorithm’s evolutionary process. A self-adaptive crossover and mutation operator, which adjusts according to the number of iterations, is designed to allow the algorithm to converge faster in the early stages of operation and better preserve population diversity and high-fitness individuals in the later stages, thus improving algorithm performance. Finally, through simulation examples, an analysis is conducted on the monthly production volume of the company’s three major product categories, as well as the monthly production, available sales, and demand quantities, end-of-month inventory, stock-to-sales ratio, and inventory turnover rate of five typical products. The results demonstrate that the MPS obtained using the proposed model and algorithm achieves comprehensive optimization.OPEN ACCESS Received: 22/07/2024 Accepted: 01/11/2024 Published: 07/04/202
Synthesis of hybrid acrylic-polyurethane biobased systems for adhesive applications
No full textHybrid acrylic/water-based polyurethane systems have been synthesized by a polymerization process in which acrylic monomers have been used as solvents in polyurethane systems. The polymerization has been carried out in four main stages The first stage in which a prepolymer has been obtained, a second stage in which the chain extension has been carried out. In the third stage has obtained the phase inversion and finally in the last stage has been carried out the synthesis of acrylic monomers. Polymerization was monitored by ATR-FTIR and gravimetry. The effect of incorporating a bifunctional chain extender and replacing a conventional PPG polyol with two types of commercial biopolyols (Priplast 1900, 48% renewable and Priplast 3294, 100% renewable) was analyzed. It has been proven that the addition of a second bifunctional chain extender improves the adhesive properties of the hybrid system, an effect that is enhanced by the use of biopolyols. It has been proven that the use of bio-based polyols is possible since they do not significantly reduce thermal properties, making it feasible to obtain a material with 20% renewable content
Comprehensive approach, basic-clinical-psychosocial, for respiratory diseases (SARS-CoV-2 model)
No full textClinical manifestations in patients affected by severe acute respiratory syndrome coronavirus 2 have been reported and its management has been suggested and followed by different international protocols. Due to the nature of the pandemic, the World Health Organization was active from the beginning of the epidemiological event and the different national entities throughout the world shared success stories in relation to treatment. Considering diagnostic and treatment tools, not only for this viral manifestation in the world, it is advisable to make a comprehensive evaluation of the challenge faced by health administration entities. The study and management of the medical event from different fields of knowledge offers a greater number of possibilities in the health management system, which can lead to a more efficient treatment of the disease. This review is highlights the importance of the analysis of SARS-CoV-2, focused on clinical, molecular and psychosocial aspects. With the search equations developed in different databases and search engines, more than 1,450 documents were found that had common characteristics. With the use of delimitation tools, 47 documents were analyzed and reported, highlighting the importance of a multidimensional analysis of an epidemiological event