Scipedia
Not a member yet
33380 research outputs found
Sort by
Invasive Lionfish in Atlantic Reef Ecosystems: A Bibliometric Review of Contemporary Research and the Vulnerability of Certain Prey Species.
No full textInvasive lionfish (''Pterois volitans'' and ''Pterois miles'') have become a significant threat to Atlantic marine ecosystems, outcompeting native species through rapid reproduction and predation. This bibliometric study of contemporary research examines the growing research interest in lionfish since their introduction to the Atlantic in the late 20th century through an analysis of academic publications from 1980 to 2020 comparing lionfish studies with research on seven different Atlantic grouper species (Epinephelinae), which served as controls due to their shared ecological trophic level. While lionfish-focused research has steadily increased, statistical analysis (paired t-tests) showed no significant difference in publication rates compared to grouper studies. Additionally, an analysis of five observational studies on lionfish stomach contents revealed a preference for small, schooling, pelagic fish, such as grunts (Haemulidae), particularly those active during twilight hours. Lionfish consume prey at alarming rates in Atlantic reef ecosystems, uhindered by the biotic factors of native predators or parasites. Their diet overlaps with native mesopredators, including the economically valuable groupers, further threatening these species by depleting juvenile populations and monopolizing resources.The findings highlight lionfish as a growing ecological and economic concern for Atlantic marine ecosystems. Their unprecedented proliferation underscores the urgent need for targeted interventions to mitigate their impact on biodiversity and support the resilience of native marine communities
Fundamental Theorems and Wave Dynamics in Rotating Thermoelastic Diffusion with Multi-Phase Delays and Temperature-Dependent Properties
Full text linkThe current study uses a novel mathematical formulation of temperaturedependent thermoelastic diffusion with multi-phase delays in a rotating frame of reference (TDMR). Higher order time derivatives are included for the diffusing mass flux, the gradient of chemical potential, the gradient of temperature, and the TDMR model of heat flow vector in Fourier’s and Fick’s laws. The fundamental theorems (energy, uniqueness, reciprocity, and variational criterion) are examined using the preliminary equations for the simulated model TDMR. Reciprocity theorem applications are taken for particular scenarios including body forces, heat sources, and chemical potential sources. It has been noted that the variational criteria and these theorems are mostly influenced by the field variables’ susceptibility and the variations in the parameters of higher-order temporal derivatives. The two-dimensional example of the assumed model’s planar wave propagation is also provided. Four connected longitudinal waves have been identified: the primary (P) wave, secondary (S) wave, thermal (T) wave, and chemical potential (CP) wave. Wave properties such as phase velocity and attenuation coefficient are estimated numerically and displayed visually. A few special examples are also investigated and connected with the established outcomes. This work provides a foundation for further research into basic issues in thermoelastic continua under various physical field factors. Numerous applications in material science, geomechanics, soil dynamics, and the electronic sector can be made of the current findings.OPEN ACCESS Received: 22/02/2025 Accepted: 11/04/2025 Published: 30/06/202
A methodology to estimate the fiber tow position during the fiber placement manufacturing processes of FRP laminates to homogenize the laminate’s permeability
Full text linkEuropean Efficiency Schemes for Domestic Gas Boilers: Estimation of Savings in Heating of Settlements
Full text linkThis article aims to evaluate the seasonal efficiency of natural gas boilers used in European households, highlighting the cost effectiveness, environmental benefits, and user comfort associated with higher-efficiency models, particularly those based on condensing technology. The study applies a standardized algorithm used in European energy labeling schemes to calculate the seasonal efficiency of household gas boilers. It further includes a comparative analysis of selected boiler models available on the Serbian market and outlines a step-by-step method for estimating gas savings when replacing older, less efficient boilers with modern units. Condensing boilers demonstrate significantly higher seasonal efficiency than standard models by recovering additional heat from exhaust gases. These improved boilers produce lower greenhouse gas emissions and offer annual fuel savings of approximately 10% to 30%, depending on the boiler’s age, system design, and usage patterns. The results also confirm the direct correlation between seasonal efficiency and annual fuel consumption, validating the use of efficiency-based cost comparisons. The analysis focuses on residential gas boilers available in the Serbian market, although the models examined are commonly distributed across Europe. The findings highlight the important role of energy efficiency labels—based on a standardized algorithm—in guiding boiler selection, helping consumers and policymakers make informed decisions that promote energy savings and reduce environmental impact. This article contributes to the theoretical and practical understanding of gas boiler efficiency by integrating algorithm-based evaluation with market data and user-centered considerations. It offers actionable insights for consumers, energy advisors, and policymakers in the context of Europe’s energy transition. Verifying the efficiency calculations of gas boilers requires a careful combination of theoretical methods, measured data, and adherence to standards
Iber v3. Reference manual and GUI. Non-Newtonian shallow flows calculation module
No full textIber is a two-dimensional hydraulic model for the simulation of free surface flow in rivers and estuaries, and the simulation of environmental processes in fluvial hydraulics. Since the release of the first version of Iber, which included a hydrodynamic calculation engine fully coupled with sediment transport processes and turbulence, it has evolved to become a free surface flow modelling tool for highly complex environmental processes. This document presents the developments made for version 3, specifically, for the new calculation module for the simulation of shallow non-Newtonian flows called IberNNF. The shallow water equations are solved using an ad-hoc numerical scheme focused on the simulation of this type of flow in nature (e.g., steep slopes, irregular geometries). The graphical user interface (GUI) has been adapted to the module's new features to achieve a simple and user-friendly workflow
Non-Neutral by Design: Why Generative Models Cannot Escape Linguistic Training
Full text linkThis article investigates the structural impossibility of semantic neutrality in large language models (LLMs), using GPT as a test subject. It argues that even under strictly formal prompting conditions, such as invented symbolic systems or syntactic proto-languages, GPT reactivates latent semantic structures drawn from its training corpus. The analysis builds upon prior work on syntactic authority, post-referential logic, and algorithmic discourse (Startari, 2025), and introduces empirical tests designed to isolate the model from known linguistic content. These tests demonstrate GPT’s consistent failure to interpret or generate structure without semantic interference. The study proposes a falsifiable framework to define and detect semantic contamination in generative systems, asserting that such contamination is not incidental but intrinsic to the architecture of probabilistic language models. The findings challenge prevailing narratives of user-driven interactivity and formal control, establishing that GPT(and similar systems) are non-neutral by design
Welding thermoplastic composites using resistive heating: tooling design, joining procedure and demonstrator manufacturing
No full textThermoplastic welding technology is a long-established technology in the industry where the efficiency of the welded joint can be approached to the properties of the base material by fast, automated and reversible joining. The joining of two thermoplastic compounds can be done by fusion bonding and reconsolidation of the pieces in the joining line. The most promising fusion bonding techniques, and nowadays with more presence in the aeronautical sector, are resistance welding, induction welding, ultrasonic welding and laser welding. Among these methods, the advantage of resistance welding is that the heat is produced exactly at the interface to be welded, avoiding unwanted heating in other parts of the piece. This method is based on the application of an electrically conductive implant between the two parts to be welded under pressure that generates heat with the passage of current. The objective of this work was to develop a resistance welding system for the joining of a thermoplastic composite assembly. A demonstrator of a representative element of the aeronautical sector was manufactured in carbon fiber and PPS composite material consisting of a skin to which two L-shaped brackets made of the same material as the skin were welded. The welding process carried out and the electrical and thermal parameters obtained show the repeatability of this process. This technology could be easily scalable for the welding of larger elements and different geometries
AUTOMATED MANUFACTURING OF THERMOPLASTIC COMPOSITES FOR HYDROGEN STORAGE
No full textThe research work is focused on developing thermoplastic composites by automated tape laying process (ATL) having acceptable gas permeability levels to store hydrogen H2 in linerless composite material tanks at cryogenic temperatures. Carbon fibre (CF) with polyamide 11 (PA11) matrix was used to manufacture composites using automated tape laying process. The manufactured composites treated in autoclave and tested for hydrogen permeability at room temperature. The results show that autoclave cured CF/PA11 composites meet the set permeability requirements for composite hydrogen storage vessel designed for pressure of 6 bar. 
Desafíos y estrategias de optimización en la soldadura ultrasónica continua robótica de CFR-TP
No full textLa soldadura ultrasónica continua robótica (cUSW) es una técnica prometedora para unir termoplásticos reforzados con fibra de carbono (CFR-TP), que ofrece alta eficiencia y tiempos de procesamiento rápidos. Sin embargo, mantener la calidad de la soldadura y la robustez del proceso presenta desafíos significativos. Las características de la soldadura, como la resistencia de la unión y el rendimiento a largo plazo, se ven fuertemente influenciadas por parámetros clave durante las fases de generación de calor y consolidación. Comprender las interacciones entre el sistema robótico y el proceso de soldadura ultrasónica es esencial, ya que impactan directamente en la calidad y consistencia de la soldadura. El robot debe controlar con precisión el movimiento del sonotrodo durante la fase de generación de calor para mantener una fuerza constante, precisión de trayectoria y uniformidad de velocidad, asegurando una transferencia de energía eficiente y una fusión uniforme. Durante la consolidación, tanto la velocidad como la fuerza son cruciales, controlando la disipación de calor para reducir la temperatura de la interfaz por debajo del punto de cristalización y prevenir defectos. Para abordar estos desafíos, es esencial la monitorización en tiempo real de los parámetros clave del proceso. La integración avanzada de sensores y las estrategias de control basadas en datos permiten ajustes dinámicos para optimizar las condiciones de soldadura y prevenir defectos. Este artículo explora los desafíos asociados con la soldadura ultrasónica continua robótica de CFR-TP y analiza técnicas de monitoreo y estrategias de control para mejorar la consistencia de la soldadura y la confiabilidad del proceso
Regulatory Legitimacy Without Referents: On the Syntax of AI Generated Legal Drafts
Full text linkThis article analyzes how AI-generated legal texts simulate legitimacy without referencing a sovereign authority. Based on a provenance-verified corpus of machine-generated documents, including contracts, terms of service, and automated policy clauses, the study shows that the legislator is structurally displaced by recurring patterns of passive voice, normative conditionals, and chains of subordinate clauses. The result is legalidad sin fuente (sourceless legality), where the appearance of regulatory authority is produced by syntactic form rather than institutional attribution. Comparing these drafts with traditional legislative writing, the article outlines a typology that instantiates autoridad no referencial and identifies a dual risk: loss of authority traceability and an accountability gap in the binding effects of these texts. This syntactic delegation constitutes a paradigm of regla compilada, situated within the tradition of formal grammars, in which language enacts governance without a governing subject