Communities in PRCR
Select a community to browse its collections.
- Colecciones de la Albizu University
- Colecciones digitales de Atenas College
- Colecciones de los Centros Sor Isolina Ferré
- Materiales utilizados para la certificación.
Recent Submissions
Design of an Integrated Biomonitoring System for IVA/EVA Suits Using the Patient Assessment System (PAS)
(Polytechnic University of Puerto Rico, 2026) Raimundi Rivera, Roberto C.; Nieves Castro, Rafael A.
Advancing human spaceflight toward exploration-class missions requires autonomous health monitoring systems that operate without real time support from Earth. This article presents the design and validation of an integrated hardware platform for biomonitoring in IVA/EVA suits. The system is based on the Patient Assessment System framework and integrates sensors for heart rate, oxygen saturation, respiratory rate, and temperature. A centralized embedded
microcontroller performs local acquisition, signal processing, storage, and alert generation. Experimental and simulation results demonstrate acceptable accuracy, real-time response, and improved signal quality after motion compensation. The proposed design supports autonomous physiological assessment in constrained environments and provides a scalable foundation for future wearable biomedical systems for space and remote operations. Keywords — Biomonitoring, Embedded Systems, EVA Suits, Wearable Systems.
Development and Characterization of a Citric Acid-crosslinked Cassava Starch Hydrogel Functionalized with Aloe Vera for Potential Tissue Repair Applications
(Polytechnic University of Puerto Rico, 2026) Gutiérrez Reyes, Yvvonna; Rondón Contreras, Jairo J
This study presents the development and characterization of a bio-based hydrogel synthesized from cassava starch and citric acid through a green approach and functionalized with Aloe vera. The material was prepared using a two-stage thermal curing process (110 °C for 1 h followed by 140 °C for 30 min) and evaluated for physicochemical, electrical, and antibacterial properties. FTIR-ATR analysis indicated the formation of ester linkages associated with starch–citric acid crosslinking. Swelling analysis revealed limited aqueous stability, with several formulations showing mass loss rather than consistent swelling. Surface pH values ranged from 2.02 to 3.55, indicating a strongly acidic profile associated with residual citric acid. Electrical characterization showed a formulation-dependent response related to ionic transport within the hydrogel matrix. A qualitative reduction in Escherichia coli growth was observed; however, quantitative antibacterial analysis was not performed. Overall, the results demonstrate the influence of formulation composition on hydrogel behavior and highlight the need for further optimization and biological validation. Keywords ⎯ Aloe Vera, Cassava Starch, Citric Acid, Impedance Spectroscopy.
Potable Water Tank Management and Risk Mitigation for a Federal Healthcare Facility
(Polytechnic University of Puerto Rico, 2026) Irizarry Vega, Julio Angel; Cruzado Vélez, Héctor J.
A federal healthcare facility depends on a reliable potable water system to support patient care, sanitation, and daily operations. This project developed a structured engineering management approach for inspecting, monitoring, and maintaining a potable water tank. The methodology integrated laboratory testing, structural inspection, risk evaluation, maintenance verification, and operational planning to improve regulatory compliance and system reliability. Results demonstrated that organized inspection workflows and preventive maintenance activities can reduce operational risks and improve long-term maintenance planning. Key Terms ⎯ Engineering Management, Potable Water Tank, Risk Mitigation, Water Quality Monitoring
Proactive Obsolescence Management for Critical Control Components in STATCOM Systems
(Polytechnic University of Puerto Rico, 2026) Quiñones Kientz, Juan S.; Cruzado Vélez, Héctor J.
Obsolescence of critical control components has become a significant challenge in STATCOM manufacturing, where prolonged lead times and unavailability of spare parts increase the risk of unplanned downtime and elevated emergency costs. This project focused on the embedded control computer (CC-002) and high-frequency switching gate card (GC-002), which exhibited risk scores. The objective was to develop a proactive obsolescence management policy using the PDCA cycle. A risk prioritization matrix was constructed from ERP and CMMS data using lead time, failure rate, and downtime impact, followed by a formal multi-criteria decision analysis incorporating emergency procurement cost, cost-benefit calculations, and lifecycle costing. The analysis identified aftermarket equivalents as the preferred short-term mitigation strategy and produced a comprehensive policy that includes early warning indicators, a structured decision framework, and measurable KPIs. The resulting policy and supporting tools provide a framework that addresses supply chain vulnerability and is expected to enhance operational resilience and cost efficiency in STATCOM production. Keywords cost-benefit analysis, decision tree, risk prioritization matrix, supply chain resilience.
Optimización del proceso de manejo de materiales desde la solicitud hasta la entrega en proyectos de construcción
(Polytechnic University of Puerto Rico, 2026) Cabreja de la Cruz, Juan F.; Cruzado Vélez, Héctor J.
La gestión ineficiente de materiales en programas de construcción dispersos genera atrasos, errores y sobrecostos que comprometen el cronograma del proyecto. Este estudio aplicó la metodología DMAIC para optimizar el proceso de solicitud y entrega de materiales del Programa de Reconstrucción del PRDOH, el cual opera con 80 casos activos en 15 municipios. El análisis inicial identificó que el 71% de las solicitudes se procesaban mediante canales informales, con un tiempo promedio de 4.3 días en casos con atraso y un 46% de casos superando el criterio de tres días. A partir del criterio base de cinco días, se estableció como meta una reducción mínima del 30%, con criterio de éxito de tres días o menos. Se estandarizó el flujo mediante un formulario digital y se implementó Smartsheet como plataforma centralizada. En los 43 casos procesados bajo el nuevo flujo, el tiempo promedio se redujo a 1.8 días, una reducción del 58%, con un 97% de cumplimiento.