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Bike Lane Project Implementation for Sustainable Transportation in Tuguegarao City: A Technical and Economic Perspective
No full textThe Philippines is perennially confronted with transport problems, with 11.7 million registered vehicles resulting in highly congested, poorly mobile roadways. In line with the Philippine Development Plan, which focuses on creating intermodal terminals and sheltered bike lanes to promote sustainable transportation, this study examines the technical and financial feasibility of implementing bike lanes within Tuguegarao City. Employing a mixed-methods research design, the study assessed current road conditions and traffic flow and collected insights from stakeholders. The qualitative data were collected using structured survey questionnaires, while the quantitative analysis used traffic volume data to calculate the level of service (LOS). The findings show that health and environmental benefits motivate bicycle use, while the lack of dedicated lanes and safe parking spaces discourages its adoption. However, there is high public support for bike lane implementation (mean rating: 4.48). Infrastructure constraints suggest that upgrading should precede construction. LOS results (B and D) confirm the viability of shared roads to improve traffic performance. Economic analysis also showed that the cost of bicycle investments can be recouped in 14 months through transportation benefits. These results indicate a high level of public desire to transition to cycling, provided that facilitating infrastructure and safe, dedicated cycling lanes are in place
Recent developments in detecting and localizing weaknesses in structures for high-fidelity digital twins
Get PDFGiven that all materials exposed to the environment and/or undergoing loads eventually age and fail, the task of trying to detect and localize weaknesses in structures is common to many fields. Traditionally, manual inspection was the only way of carrying out this task, aided by ultrasound, X-ray, or vibration analysis techniques. The advent of accurate, abundant and cheap sensors, together with detailed, high-fidelity computational models in an environment of digital twins has opened the possibility of enhancing and automating the detection and localization of weaknesses in structures. The procedures proposed here are based on measured forces and displacements/strains, and formulate the determination of material properties (or weaknesses) as an optimization problem for the strength factor. These procedures belong to the more general class of inverse problems where structural properties are sought based on a desired cost functional. The use of adjoint formulations and smoothing of gradients to quickly localize damaged regions makes the problem tractable. Recent developments include: extension to nonlinear materials, incorporation of uncertainty, and transient problems. Several examples show the viability, accuracy and efficiency of the proposed methodology and its potential use for high fidelity digital twins
Front tracking with a twist: the eXtreme mesh deformation approach (X-MESH)
Get PDFThe arbitrary Eulerian Lagrangian (ALE) formulation is a common approach for tracking fronts in finite element simulations. It is, however, difficult to track fronts over long distances because the mesh quality becomes poor on one side of the front. Moreover, traditional ALE front tracking cannot cope with changes in the front topology. To remedy the above problems (at least the first one), remeshing is required from time to time to maintain correct mesh approximation capability on both sides of the front. This remeshing requires projection of the field and updating of the database in the simulation, which is detrimental to the speed and accuracy. We introduce a new approach in which the set of nodes located on the front evolves over time allowing the front to migrate through the mesh. Topological changes are easily considered. For example, a front can nucleate, propagate and merge with other fronts as it propagates. For the new approach to work properly, we must accept that some elements become very small and possibly of zero measure. This means that the elements can deform in extreme ways, hence the acronym X-MESH. Surprisingly, as we shall show, this situation does not prevent simulations from being carried out. In short, X-MESH simply uses node movements to propagate fronts over long distances, even in the event of topological changes. The mesh topology remains unchanged during simulation. The size and sparsity of the finite element matrices are therefore fixed throughout the simulation, and no field projection is required. As the simulation progresses, nodes arrive and depart from the front. X-MESH's capability will be demonstrated for several important applications in mechanics and physics, such as front tracking in the Stefan phase change model or the simulation of immiscible two-phase flows. The work is funded by a European Research Council (ERC) Synergy Grant whose co-pI is Professor J-F. Remacle also at UCLouvai
A Comparative Study of a Conventional and Modern Transport-Velocity SPH Scheme in a Reactive Mass Transfer Problem
Get PDFThe advection-diffusion equation is fundamental to modeling mass transfer in various engineering applications, including solute transport in catalytic reactors, pollutant dispersion in environmental flows, and drug delivery in biological tissues. These problems often span a wide range of transport regimes, making accurate and robust numerical solutions essential for predictive modeling and design. In this work, we investigate two Weakly Compressible Smoothed Particle Hydrodynamics (WCSPH) approaches, a conventional SPH and a modern SPH with transport velocity, for modeling mass transport in a Laminar Flow Reactor (LFR), which includes advection, diffusion, and reaction effects. The study examines three Peclet numbers (Pe = 10, 1000, and 100,000), corresponding to diffusion-influenced, mixed, and advection-dominated transport regimes, respectively. Numerical results are benchmarked against COMSOL Multiphysics®. The modern SPH method demonstrates improved performance over the conventional SPH in low to moderate Peclet regimes, exhibiting reduced particle disorder, enhanced stability, and more accurate diffusion resolution. At high Peclet numbers, both approaches yield comparable results, though the modern SPH shows improved convergence and outlet concentration predictions. These findings highlight the potential of the implemented modern SPH approach for improved modeling of mass transfer in chemical reactors, particularly in diffusion-sensitive applications
Desarrollo de la tecnología de calandrado para la reutilización de residuos de pre-preg multiaxiales no curados procedentes del sector aeronáutico
No full textEsta investigación se centra en aprovechar los residuos de pregreg multicapa sin curar generados durante la producción de componentes aeronáuticos, con especial énfasis en los procesos de AFP (Automatic Fibre Placement) y ATL (Automatic Tape Laying). Estos residuos, que presentan características repetitivas en cuanto a tamaño, forma y apilado, se procesan mediante un sistema mecánico de calandrado para darle una segunda vida al material. Este método desarrollado por FIDAMC está basado en preparar los residuos de ATL de prepreg sin curar en tiras longitudinales orientadas en la dirección predominante. Posteriormente, estas tiras se procesan mediante calandrado en condiciones específicas de temperatura, velocidad y ratios de reducción de espesor en diferentes pasos. Como resultado, se obtiene un material reusado intermedio manipulable para la fabricación de nuevas piezas. Este material se ha caracterizado física-química y mecánicamente para optimizar sus propiedades mecánicas y asegurar su viabilidad como material reusado. Aunque las piezas aeroespaciales de material compuesto deben cumplir estrictos requisitos de seguridad, existen aplicaciones no críticas donde se pueden emplear materiales más ecológicos y económicos, como la fibra de carbono reusada. Esto permite una reducción significativa del impacto ambiental y de los costes asociados. Para estudiar la viabilidad de fabricación con este material, se ha fabricado un demostrador de costilla de borde de ataque del elevador (elevator) del estabilizador horizontal (HTP) mediante el proceso de termoconformado. Este estudio pretende demostrar el desarrollo y aplicación de nuevos materiales reusados, los cuales pueden ser utilizados en piezas semi-estructurales en el sector aeronáutico, o bien, en el sector transporte, en general. Se ha estudiado el material mediante una caracterización físico-química (micrografía, DSC, digestión y porosidad) y mecánica (tracción, compresión, ILSS, G1C, IPSS, CAI, OHC y FHC), así como otros métodos de caracterización avanzada. También se ha estudio su viabilidad de fabricación mediante la producción de un componente de geometría compleja. Además, se han propuesto diferentes alternativas para mejorar la calidad el material y ampliar el abanico de aplicación. Los resultados obtenidos confirmaron el potencial del material reusado para aplicaciones no críticas, demostrando que cumple con los requisitos funcionales de este tipo de componentes y recorriendo el camino hacia una mayor sostenibilidad en el sector
Real-Time Detection of Authority-Bearing Constructions Under Strict Causal Masking
Get PDFThis datasheet defines a benchmark for real-time detection of authority-bearing constructions under strict causal masking, where models access only left context. It measures how accurately and quickly a system identifies linguistic signals of authority without future tokens. Authority-bearing constructions are treated as Type-0 productions within a regla compilada, binding syntactic and operational constraints to decisions. Three hypotheses guide the study: a compact causal detector with an authority lexicon can achieve reliable precision at low latency; performance depends on construction family and register rather than sentiment; limited buffers can improve stability without breaking causality. Multilingual datasets (English, Spanish, optional French, German, Portuguese) include transcripts, hearings, and policy texts segmented into token streams. Tasks involve streaming span detection and stance classification, evaluated at multiple latency checkpoints and causal budgets (b ∈ {32, 64, 128}). Metrics cover streaming F1, AUCL, and stability index.Baselines (oracle, lexicon-only, sentiment) and strict no-lookahead validation ensure isolation of causal effects. The benchmark shows how form, not intent, governs real-time authority recognition, enabling evaluation of models for compliance and human-in-the-loop systems without right-context access. Acknowledgment / Editorial Note This article is published with editorial permission from LeFortune Academic Imprint, under whose license the text will also appear as part of the upcoming book AI Syntactic Power and Legitimacy. The present version is an autonomous preprint, structurally complete and formally self-contained. No substantive modifications are expected between this edition and the print edition. LeFortune holds non-exclusive editorial rights for collective publication within the Grammars of Power series. Open access deposit on SSRN is authorized under that framework, if citation integrity and canonical links to related works (SSRN: 10.2139/ssrn.4841065, 10.2139/ssrn.4862741, 10.2139/ssrn.4877266) are maintained
