CAREER: Framework for Integrating Embedded Sensors in Durability Analysis of FRP Composites in Civil Infrastructure

The CAREER proposal will develop a framework to characterize durability of composites in civil infrastructure by integrating fiber-optic embedded sensors with damage mechanics models and life prediction methods. To tackle this problem, a combined analytical and experimental methodology is proposed, as follows: 1) Integrate embedded sensors in composites fabrication by VARTM and filament winding; 2) Implement strain, temperature, moisture and chemical degradation fiber-optic sensors; 3) Evaluate the embedded sensor system with controlled damage; 4) Develop a damage mechanics model and life-prediction methodology for durability analysis based on interrogating senors; 5) Assess reliability of sensor data and scale to composite structures (bridge decks and pipe walls); and 6) Validate the durability methodology and synthesize into a health-monitoring protocol. The educational approach is two-fold encompassing student recruitment and advanced graduate education. First, and educational collaboration is being developed with an applied technology center at a high school in Maine. The objective is to introduce high school students to the engineering experience by collaborating with civil engineering juniors in a composite bridge design and fabrication project. Second, an advanced graduate course on composites in civil engineering will be developed

Numerical Modeling and Experimental Investigation of Effective Elastic Properties of the 3D Printed Gyroid Infill

A numerical homogenization approach is presented for the effective elastic moduli of 3D printed cellular infills. A representative volume element of the infill geometry is discretized using either shell or solid elements and analyzed using the finite element method. The elastic moduli of the bulk cellular material are obtained through longitudinal and shear deformations of a representative volume element under periodic boundary conditions. The method is used to analyze the elastic behavior of gyroid infills for varying infill densities. The approach is validated by comparing the Young’s modulus and Poisson’s ratio with those obtained from compression experiments. Results indicate that although the gyroid infill exhibits cubic symmetry, it is nearly isotropic with a low anisotropy index. The numerical predictions are used to develop semi-empirical equations of the effective elastic moduli of gyroid infills as a function of infill density in order to inform design and topology optimization workflows

Integration of Material Characterization, Thermoforming Simulation, and As-Formed Structural Analysis for Thermoplastic Composites

An improved simulation-based thermoforming design process based on the integration of material characterization and as-formed structural analysis is proposed. The tendency of thermoplastic composites to wrinkle during forming has made simulation critical to optimized manufacturing, but the material models required are complex and time consuming to create. A suite of experimental methods has been developed for measurement of several required properties of the molten thermoplastic composite. These methods have the potential to enhance thermoplastic composites manufacturing by simplifying and expediting the process. These material properties have been verified by application to thermomechanical forming predictions using commercial simulation software. The forming predictions showed improved agreement with experimental results compared to those using representative material properties. A tool for using thermoforming simulations to inform more accurate structural models has been tested on a simple case study, and produced results that clearly differ from those of models using idealized fiber orientations and thicknesses. This provides evidence that this type of as-formed analysis may be necessary in some cases, and may be further investigated as an open source alternative to commercial analysis software

Las energías renovables, concretamente la eólica, y el Impuesto sobre Transmisiones Patrimoniales

There are solid grounds on which to defend the idea that the administrative authority under which rights are recognized installation of wind turbine for electricity production is not subject to ITP, and he's not only not under lack of administrative concession in the strict sense, but also hint of activity of social benefits of public services, or comparable-in production, or wind power generation.Existen razones sólidas sobre las cuales defender la idea de que la autorización administrativa en virtud de la cual se reconocen derechos de instalación de parques de aerogeneradores para la producción de energía eléctrica no está sujeta al ITP, y no lo está no solo en virtud de la inexistencia de concesión administrativa en sentido estricto, sino tampoco de atisbo alguno de actividad prestacional de servicios públicos –o equiparables– en la producción, o sea, generación de energía eólica

Regulation of the PMP22 gene through an intronic enhancer

Successful myelination of the peripheral nervous system depends upon induction of major protein components of myelin, such as Peripheral Myelin Protein 22 (PMP22). Myelin stability is also sensitive to levels of PMP22, as a 1.4 Mb duplication on human chromosome 17, resulting in 3 copies of PMP22, is the most common cause of the peripheral neuropathy, Charcot-Marie-Tooth disease (CMT). The transcription factor Egr2/Krox20 is required for induction of high level expression of Pmp22 in Schwann cells but its activation elements have not yet been determined. Using chromatin immunoprecipitation analysis of the rat Pmp22 locus, we find a major peak of Egr2 binding within the large intron of the Pmp22 gene. Analysis of a 250 bp region within the largest intron showed that it is strongly activated by Egr2 expression in reporter assays. Moreover, this region contains conserved binding sites for not only Egr2 but also Sox10, which is also required for Schwann cell development. Our analysis shows that Sox10 is required for optimal activity of the intronic site as well as PMP22 expression. Finally, mouse transgenic analysis revealed tissue-specific expression of this intronic sequence in peripheral nerve. Overall, these data show that Egr2 and Sox10 activity are directly involved in mediating the developmental induction of Pmp22 expression

The use of deep learning to improve player engagement in a video game through a dynamic difficulty adjustment based on skills classification

The balance between game difficulty and player skill in the evolving landscape of the video game industry is a significant factor in player engagement. This study introduces a deep learning (DL) approach to enhance gameplay by dynamically adjusting game difficulty based on a player’s skill level. Our methodology aims to prevent player disengagement, which can occur if the game difficulty significantly exceeds or falls short of the player’s skill level. Our evaluation indicates that such dynamic adjustment leads to improved gameplay and increased player involvement, with 90% of the players reporting high game enjoyment and immersion levels

Effects of Fiber Orientation on the Coefficient of Thermal Expansion of Fiber-Filled Polymer Systems in Large Format Polymer Extrusion-Based Additive Manufacturing

Large format polymer extrusion-based additive manufacturing has been studied recently due to its capacity for high throughput, customizable bead size and geometry, and ability to manufacture large parts. Samples from three fiber-filled amorphous thermoplastic materials 3D printed using a Masterprint 3X machine from Ingersoll Machine Tools were studied, along with their neat counterparts. Characterization techniques included thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and thermo-mechanical analysis (TMA). TGA results showed that the fillers decreased the degradation temperature for most of the materials investigated, with a 30°C decrease for polycarbonate (PC) and a 12°C decrease for polyethylene terephthalate glycol (PETG). For all the materials used, heat capacity increases with increasing temperature. Moreover, results show that a highly conductive filler increases the heat capacity. In contrast, a material with a lower conductivity decreases the heat capacity indicated in the 15.2% and 2.54% increase for acrylonitrile butadiene styrene (ABS) and PC and a 27.68% decrease for PETG. The TMA data show that the printed bead exhibits directional properties consistent with an orthotropic material. Smaller strains and coefficient of thermal expansion (CTE) were measured along the bead direction and across the bead compared to the through bead thickness showing that fillers are predominantly oriented in the bead direction, which is consistent with the literature. CTE values through bead thickness and neat material are similar in magnitude, which corresponds to the CTE of the matrix material. The experimental results serve to characterize the effect of fiber filler on the part thermal strains in three principal directions and two-part locations during the extrusion and bead deposition of large-format polymer extrusion-based additive manufacturing technologies

A distributed system for microelectronic algorithms

Microelectronics tools tend to consume large amounts of memory and processor time. When circuit size outgrows the resources available on a station, its time for a scalable tool architecture. Applied to design rule checking of jlattened masks, this distributed; object-oriented architecture summons together the power of small, cheap desktop computers. The distributed system enables processing of larger circuits, assigning distinct parts of the problem to each machine. Larger circuits can be tested and testing time reduced as more computers are aggregated to the process