Directly Indecomposables in Semidegenerate Varieties of Connected po-Groupoids

We study varieties with a term-definable poset structure, "po-groupoids". It is known that connected posets have the "strict refinement property" (SRP). In [arXiv:0808.1860v1 [math.LO]] it is proved that semidegenerate varieties with the SRP have definable factor congruences and if the similarity type is finite, directly indecomposables are axiomatizable by a set of first-order sentences. We obtain such a set for semidegenerate varieties of connected po-groupoids and show its quantifier complexity is bounded in general

Efectividad de la fototerapia en la hiperbilirrubinemia neonatal

Introducción: La ictericia neonatal es la pigmentación amarilla de la piel causada por aumento de bilirrubina en sangre. Los tratamientos más utilizados para la hiperbilirrubinemia han sido la fototerapia y, la fototerapia más fenobarbital. Objetivo: Identificar las mejores evidencias para mejorar el uso y la efectividad de la fototera-pia en el tratamiento de la hiperbilirrubinemia neonatal. Métodos: Se realizó una búsqueda de artículos publicados de 2007 a 2014 con las siguientes palabras clave, hiperbilirrubinemia neonatal, fototerapia de halógenos, fototerapia LEDS, en la Biblioteca Cochrane, en las Bases de datos REDALyC, Scielo, Medline, CINAHL y CUIDEN. Se iden-tificaron 28 artículos relacionados con la efectividad de la fototerapia. Se realizó un análisis de los artículos encontrados. Resultados: La fototerapia con luz de LED tiene mayor eficacia en el control de bilirrubina sobre la fototerapia de halógeno y fibra óptica (diferencia de medias 0.43, IC 95%: 1.91 a 1.05 h). Las sábanas blancas alrededor de la cuna de calor radiante aumentan la eficacia de la fototera-pia; respecto a la protección de los genitales, la literatura menciona que si los niveles de bili-rrubina están muy altos se deberá quitar el pañal, solo cuando se utiliza la fototerapia de LEDS. Con cualquiera de los dispositivos de fototerapia se deberá utilizar protección ocular; se precisa que los cubre bocas o ese tipo de material no es útil para la aplicación de esta.Conclusiones:La fototerapia de mayor efectividad es de LEDS, las sábanas blancas aumentan la efectividad de la fototerapia, se puede quitar el pañal del neonato cuando la bilirrubina haya incrementado

Continuous Plasma density measurement in TJ-II infrared interferometer-Advanced signal processing based on FPGAs

This work presents the behavioral simulation in an FPGA of a novel processing system for measuring line average electronic density in the TJ-II stellarator diagnostic, Infra-Red Two-Color Interferometer. Line average electronic density is proportional to phase difference between probing and reference signals of the interferometer, as the Appleton–Hartree cold plasma model states. The novelty of the approach is the development of a real time measuring system where research work has been carried out in two ways: a new interpolation algorithm and the implementation of a new specific processor on an FPGA. The main goal of this new system is to measure line plasma electronic density for several channels in real time, also it will be useful to eliminate intermediate mixing frequency stages (the output signals coming from the interferometer are going to be directly sampled) and finally to generate real time density signals for control purposes in TJ-II and in other diagnostics. This device is intended to be the new data acquisition-processing system for the future six channel infrared interferometer that requires at least 14 input signals. The knowledge acquired could be useful in the design of W7-X and ITER IR-interferometer data acquisition and processing systems

Numerical Modelling of Ballistic Impact Response at Low Velocity in Aramid Fabrics

[EN] In this study, the effect of the impact angle of a projectile during low-velocity impact on Kevlar fabrics has been investigated using a simplified numerical model. The implementation of mesoscale models is complex and usually involves long computation time, in contrast to the practical industry needs to obtain accurate results rapidly. In addition, when the simulation includes more than one layer of composite ply, the computational time increases even in the case of hybrid models. With the goal of providing useful and rapid prediction tools to the industry, a simplified model has been developed in this work. The model offers an advantage in the reduced computational time compared to a full 3D model (around a 90% faster). The proposed model has been validated against equivalent experimental and numerical results reported in the literature with acceptable deviations and accuracies for design requirements. The proposed numerical model allows the study of the influence of the geometry on the impact response of the composite. Finally, after a parametric study related to the number of layers and angle of impact, using a response surface methodology, a mechanistic model and a surface diagram have been presented in order to help with the calculation of the ballistic limit.This research was funded by the Ministry of Economy and Competitiveness from Spain, grant number BES-2012-055162 and the international collaborations subprogram under the reference EEBB-I-2016-11586.Feito-Sánchez, N.; Loya, J.; Muñoz-Sánchez, A.; Das, R. (2019). Numerical Modelling of Ballistic Impact Response at Low Velocity in Aramid Fabrics. Materials. 12(13):1-15. https://doi.org/10.3390/ma121320871151213Tabiei, A., & Nilakantan, G. (2008). Ballistic Impact of Dry Woven Fabric Composites: A Review. Applied Mechanics Reviews, 61(1). doi:10.1115/1.2821711Lim, C. ., Tan, V. B. ., & Cheong, C. . (2002). Perforation of high-strength double-ply fabric system by varying shaped projectiles. International Journal of Impact Engineering, 27(6), 577-591. doi:10.1016/s0734-743x(02)00004-0Tan, V. B. ., Lim, C. ., & Cheong, C. . (2003). Perforation of high-strength fabric by projectiles of different geometry. International Journal of Impact Engineering, 28(2), 207-222. doi:10.1016/s0734-743x(02)00055-6Shim, V. P. W., Tan, V. B. C., & Tay, T. E. (1995). Modelling deformation and damage characteristics of woven fabric under small projectile impact. International Journal of Impact Engineering, 16(4), 585-605. doi:10.1016/0734-743x(94)00063-3Park, Y., Kim, Y., Baluch, A. H., & Kim, C.-G. (2014). Empirical study of the high velocity impact energy absorption characteristics of shear thickening fluid (STF) impregnated Kevlar fabric. International Journal of Impact Engineering, 72, 67-74. doi:10.1016/j.ijimpeng.2014.05.007Taraghi, I., Fereidoon, A., & Taheri-Behrooz, F. (2014). Low-velocity impact response of woven Kevlar/epoxy laminated composites reinforced with multi-walled carbon nanotubes at ambient and low temperatures. Materials & Design, 53, 152-158. doi:10.1016/j.matdes.2013.06.051Nilakantan, G., Merrill, R. L., Keefe, M., Gillespie, J. W., & Wetzel, E. D. (2015). Experimental investigation of the role of frictional yarn pull-out and windowing on the probabilistic impact response of kevlar fabrics. Composites Part B: Engineering, 68, 215-229. doi:10.1016/j.compositesb.2014.08.033López-Gálvez, H., Rodriguez-Millán, M., Feito, N., & Miguelez, H. (2016). A method for inter-yarn friction coefficient calculation for plain wave of aramid fibers. Mechanics Research Communications, 74, 52-56. doi:10.1016/j.mechrescom.2016.04.004Duan, Y., Keefe, M., Bogetti, T. A., Cheeseman, B. A., & Powers, B. (2006). A numerical investigation of the influence of friction on energy absorption by a high-strength fabric subjected to ballistic impact. International Journal of Impact Engineering, 32(8), 1299-1312. doi:10.1016/j.ijimpeng.2004.11.005Cunniff, P. M. (1992). An Analysis of the System Effects in Woven Fabrics under Ballistic Impact. Textile Research Journal, 62(9), 495-509. doi:10.1177/004051759206200902Pan, N., Lin, Y., Wang, X., & Postle, R. (2000). An Oblique Fiber Bundle Test and Analysis. Textile Research Journal, 70(8), 671-674. doi:10.1177/004051750007000803Ha-Minh, C., Imad, A., Boussu, F., & Kanit, T. (2016). Experimental and numerical investigation of a 3D woven fabric subjected to a ballistic impact. International Journal of Impact Engineering, 88, 91-101. doi:10.1016/j.ijimpeng.2015.08.011Chocron Benloulo, I. S., Rodríguez, J., Martínez, M. A., & Sánchez Gálvez, V. (1997). Dynamic tensile testing of aramid and polyethylene fiber composites. International Journal of Impact Engineering, 19(2), 135-146. doi:10.1016/s0734-743x(96)00017-6Cheeseman, B. A., & Bogetti, T. A. (2003). Ballistic impact into fabric and compliant composite laminates. Composite Structures, 61(1-2), 161-173. doi:10.1016/s0263-8223(03)00029-1Rodriguez, J., Chocron, I. S., Martinez, M. A., & Sánchez-Gálvez, V. (1996). High strain rate properties of aramid and polyethylene woven fabric composites. Composites Part B: Engineering, 27(2), 147-154. doi:10.1016/1359-8368(95)00036-4Garcia, C., Trendafilova, I., & Zucchelli, A. (2018). The Effect of Polycaprolactone Nanofibers on the Dynamic and Impact Behavior of Glass Fibre Reinforced Polymer Composites. Journal of Composites Science, 2(3), 43. doi:10.3390/jcs2030043Garcia, C., & Trendafilova, I. (2019). Triboelectric sensor as a dual system for impact monitoring and prediction of the damage in composite structures. Nano Energy, 60, 527-535. doi:10.1016/j.nanoen.2019.03.070ARUNIIT, A., KERS, J., GOLJANDIN, D., SAARNA, M., TALL, K., MAJAK, J., & HERRANEN, H. (2011). Particulate Filled Composite Plastic Materials from Recycled Glass Fibre Reinforced Plastics. Materials Science, 17(3). doi:10.5755/j01.ms.17.3.593Ramaiah, G. B., Chennaiah, R. Y., & Satyanarayanarao, G. K. (2010). Investigation and modeling on protective textiles using artificial neural networks for defense applications. Materials Science and Engineering: B, 168(1-3), 100-105. doi:10.1016/j.mseb.2009.12.029Lopes, C. S., Seresta, O., Coquet, Y., Gürdal, Z., Camanho, P. P., & Thuis, B. (2009). Low-velocity impact damage on dispersed stacking sequence laminates. Part I: Experiments. Composites Science and Technology, 69(7-8), 926-936. doi:10.1016/j.compscitech.2009.02.009Duan, Y., Keefe, M., Bogetti, T. A., & Cheeseman, B. A. (2005). Modeling the role of friction during ballistic impact of a high-strength plain-weave fabric. Composite Structures, 68(3), 331-337. doi:10.1016/j.compstruct.2004.03.026Rao, M. P., Duan, Y., Keefe, M., Powers, B. M., & Bogetti, T. A. (2009). Modeling the effects of yarn material properties and friction on the ballistic impact of a plain-weave fabric. Composite Structures, 89(4), 556-566. doi:10.1016/j.compstruct.2008.11.012Nilakantan, G., Keefe, M., Wetzel, E. D., Bogetti, T. A., & Gillespie, J. W. (2011). Computational modeling of the probabilistic impact response of flexible fabrics. Composite Structures, 93(12), 3163-3174. doi:10.1016/j.compstruct.2011.06.013Nilakantan, G., & Gillespie, J. W. (2012). Ballistic impact modeling of woven fabrics considering yarn strength, friction, projectile impact location, and fabric boundary condition effects. Composite Structures, 94(12), 3624-3634. doi:10.1016/j.compstruct.2012.05.030Nilakantan, G., Wetzel, E. D., Bogetti, T. A., & Gillespie, J. W. (2012). Finite element analysis of projectile size and shape effects on the probabilistic penetration response of high strength fabrics. Composite Structures, 94(5), 1846-1854. doi:10.1016/j.compstruct.2011.12.028Nilakantan, G., Wetzel, E. D., Bogetti, T. A., & Gillespie, J. W. (2013). A deterministic finite element analysis of the effects of projectile characteristics on the impact response of fully clamped flexible woven fabrics. Composite Structures, 95, 191-201. doi:10.1016/j.compstruct.2012.07.023Nilakantan, G., & Nutt, S. (2014). Effects of fabric target shape and size on the V50 ballistic impact response of soft body armor. Composite Structures, 116, 661-669. doi:10.1016/j.compstruct.2014.06.002Grujicic, M., Bell, W. C., Arakere, G., He, T., & Cheeseman, B. A. (2009). A meso-scale unit-cell based material model for the single-ply flexible-fabric armor. Materials & Design, 30(9), 3690-3704. doi:10.1016/j.matdes.2009.02.008Grujicic, M., Arakere, G., He, T., Bell, W. C., Glomski, P. S., & Cheeseman, B. A. (2009). Multi-scale ballistic material modeling of cross-plied compliant composites. Composites Part B: Engineering, 40(6), 468-482. doi:10.1016/j.compositesb.2009.02.002Barauskas, R., & Abraitienė, A. (2007). Computational analysis of impact of a bullet against the multilayer fabrics in LS-DYNA. International Journal of Impact Engineering, 34(7), 1286-1305. doi:10.1016/j.ijimpeng.2006.06.002Ha-Minh, C., Boussu, F., Kanit, T., Crépin, D., & Imad, A. (2011). Analysis on failure mechanisms of an interlock woven fabric under ballistic impact. Engineering Failure Analysis, 18(8), 2179-2187. doi:10.1016/j.engfailanal.2011.07.011Ha-Minh, C., Imad, A., Kanit, T., & Boussu, F. (2013). Numerical analysis of a ballistic impact on textile fabric. International Journal of Mechanical Sciences, 69, 32-39. doi:10.1016/j.ijmecsci.2013.01.014Park, Y., Kim, Y., Baluch, A. H., & Kim, C.-G. (2015). Numerical simulation and empirical comparison of the high velocity impact of STF impregnated Kevlar fabric using friction effects. Composite Structures, 125, 520-529. doi:10.1016/j.compstruct.2015.02.041Chu, T.-L., Ha-Minh, C., & Imad, A. (2016). A numerical investigation of the influence of yarn mechanical and physical properties on the ballistic impact behavior of a Kevlar KM2 ® woven fabric. Composites Part B: Engineering, 95, 144-154. doi:10.1016/j.compositesb.2016.03.018Das, S., Jagan, S., Shaw, A., & Pal, A. (2015). Determination of inter-yarn friction and its effect on ballistic response of para-aramid woven fabric under low velocity impact. Composite Structures, 120, 129-140. doi:10.1016/j.compstruct.2014.09.063Nilakantan, G., & Gillespie, J. W. (2013). Yarn pull-out behavior of plain woven Kevlar fabrics: Effect of yarn sizing, pullout rate, and fabric pre-tension. Composite Structures, 101, 215-224. doi:10.1016/j.compstruct.2013.02.018Nilakantan, G., & Nutt, S. (2014). Effects of clamping design on the ballistic impact response of soft body armor. Composite Structures, 108, 137-150. doi:10.1016/j.compstruct.2013.09.017Rao, M. P., Nilakantan, G., Keefe, M., Powers, B. M., & Bogetti, T. A. (2009). Global/Local Modeling of Ballistic Impact onto Woven Fabrics. Journal of Composite Materials, 43(5), 445-467. doi:10.1177/0021998308097684Nilakantan, G., Keefe, M., Bogetti, T. A., Adkinson, R., & Gillespie, J. W. (2010). On the finite element analysis of woven fabric impact using multiscale modeling techniques. International Journal of Solids and Structures, 47(17), 2300-2315. doi:10.1016/j.ijsolstr.2010.04.029Nilakantan, G., Keefe, M., Bogetti, T. A., & Gillespie, J. W. (2010). Multiscale modeling of the impact of textile fabrics based on hybrid element analysis. International Journal of Impact Engineering, 37(10), 1056-1071. doi:10.1016/j.ijimpeng.2010.04.007Ha-Minh, C., Kanit, T., Boussu, F., & Imad, A. (2011). Numerical multi-scale modeling for textile woven fabric against ballistic impact. Computational Materials Science, 50(7), 2172-2184. doi:10.1016/j.commatsci.2011.02.029Lozano-Mínguez, E., Palomar, M., Infante-García, D., Rupérez, M. J., & Giner, E. (2018). Assessment of mechanical properties of human head tissues for trauma modelling. International Journal for Numerical Methods in Biomedical Engineering, 34(5), e2962. doi:10.1002/cnm.2962Palomar, M., Lozano-Mínguez, E., Rodríguez-Millán, M., Miguélez, M. H., & Giner, E. (2018). Relevant factors in the design of composite ballistic helmets. Composite Structures, 201, 49-61. doi:10.1016/j.compstruct.2018.05.076Moure, M. M., Feito, N., Aranda-Ruiz, J., Loya, J. A., & Rodriguez-Millan, M. (2019). On the characterization and modelling of high-performance para-aramid fabrics. Composite Structures, 212, 326-337. doi:10.1016/j.compstruct.2019.01.049Abtew, M. A., Boussu, F., Bruniaux, P., Loghin, C., & Cristian, I. (2019). Ballistic impact mechanisms – A review on textiles and fibre-reinforced composites impact responses. Composite Structures, 223, 110966. doi:10.1016/j.compstruct.2019.11096

Ultrasonic characterization of the pulmonary venous wall: echographic and histological correlation

Background: Pulmonary vein isolation with radiofrequency catheter ablation techniques is used to prevent recurrences of human atrial fibrillation. Visualization of the architecture at the venoatrial junction could be crucial for these ablative techniques. Our study assesses the potential for intravascular ultrasound to provide this information. Methods and Results: We retrieved 32 pulmonary veins from 8 patients dying from noncardiac causes. We obtained cross-sectional intravascular ultrasound (IVUS) images with a 3.2F, 30-MHz ultrasound catheter at intervals on each vein. Histological cross-sections at the intervals allowed comparisons with ultrasonic images. The pulmonary venous wall at the venoatrial junction revealed a 3-layered ultrasonic pattern. The inner echogenic layer represents both endothelium and connective tissue of the media (mean maximal thickness, 1.4±0.3 mm). The middle hypoechogenic stratum corresponds to the sleeves of left atrial myocardium surrounding the external aspect of the venous media. This layer was thickest at the venoatrial junction (mean maximal thickness, 2.6±0.8 mm) and decreased toward the lung hilum. The outer echodense layer corresponds to fibro-fatty adventitial tissue (mean maximal thickness, 2.15±0.36 mm). We found a close agreement among the IVUS and histological measurements for maximal luminal diameter (mean difference, -0.12±1.3 mm) and maximal muscular thickness (mean difference, 0.17±0.13 mm) using the Bland and Altman method. Conclusions: Our experimental study demonstrates for the first time that IVUS images of the pulmonary veins can provide information on the distal limits and thickness of the myocardial sleeves and can be a valuable tool to help accurate targeting during ablative procedures

Analysis of the Machinability of Carbon Fiber Composite Materials in Function of Tool Wear and Cutting Parameters Using the Artificial Neural Network Approach

[EN] Local delamination is the most undesirable damage associated with drilling carbon fiber reinforced composite materials (CFRPs). This defect reduces the structural integrity of the material, which affects the residual strength of the assembled components. A positive correlation between delamination extension and thrust force during the drilling process is reported in literature. The abrasive effect of the carbon fibers modifies the geometry of the fresh tool, which increases the thrust force and, in consequence, the induced damage in the workpiece. Using a control system based on an artificial neural network (ANN), an analysis of the influence of the tool wear in the thrust force during the drilling of CFRP laminate to reduce the damage is developed. The spindle speed, feed rate, and drill point angle are also included as input parameters of the study. The training and testing of the ANN model are carried out with experimental drilling tests using uncoated carbide helicoidal tools. The data were trained using error-back propagation-training algorithm (EBPTA). The use of the neural network rapidly provides results of the thrust force evolution in function of the tool wear and cutting parameters. The obtained results can be used by the industry as a guide to control the impact of the wear of the tool in the quality of the finished workpiece.The Ministry of Economy and Competitiveness of Spain, projects DPI2017-89197-C2-1-R and DPI2017-89197-C2-2-R] and the Ministry of Science, Innovation and Universities, grant number [FJCI-2017-34910], funded this research.Feito-Sánchez, N.; Muñoz-Sánchez, A.; Diaz-Alvarez, A.; Loya, J. (2019). Analysis of the Machinability of Carbon Fiber Composite Materials in Function of Tool Wear and Cutting Parameters Using the Artificial Neural Network Approach. Materials. 12(17):1-13. https://doi.org/10.3390/ma12172747S1131217Huang, X. (2009). Fabrication and Properties of Carbon Fibers. Materials, 2(4), 2369-2403. doi:10.3390/ma2042369Yang, Y., Jiang, Y., Liang, H., Yin, X., & Huang, Y. (2019). Study on Tensile Properties of CFRP Plates under Elevated Temperature Exposure. Materials, 12(12), 1995. doi:10.3390/ma12121995Liu, D., Tang, Y., & Cong, W. L. (2012). A review of mechanical drilling for composite laminates. Composite Structures, 94(4), 1265-1279. doi:10.1016/j.compstruct.2011.11.024Hocheng, H., & Tsao, C. . (2003). Comprehensive analysis of delamination in drilling of composite materials with various drill bits. Journal of Materials Processing Technology, 140(1-3), 335-339. doi:10.1016/s0924-0136(03)00749-0Hocheng, H., & Tsao, C. C. (2006). Effects of special drill bits on drilling-induced delamination of composite materials. International Journal of Machine Tools and Manufacture, 46(12-13), 1403-1416. doi:10.1016/j.ijmachtools.2005.10.004Hocheng, H., & Tsao, C. C. (2005). The path towards delamination-free drilling of composite materials. Journal of Materials Processing Technology, 167(2-3), 251-264. doi:10.1016/j.jmatprotec.2005.06.039Davim, J. ., & Reis, P. (2003). Study of delamination in drilling carbon fiber reinforced plastics (CFRP) using design experiments. Composite Structures, 59(4), 481-487. doi:10.1016/s0263-8223(02)00257-xSardiñas, R. Q., Reis, P., & Davim, J. P. (2006). Multi-objective optimization of cutting parameters for drilling laminate composite materials by using genetic algorithms. Composites Science and Technology, 66(15), 3083-3088. doi:10.1016/j.compscitech.2006.05.003Fernandes, M., & Cook, C. (2006). Drilling of carbon composites using a one shot drill bit. Part I: Five stage representation of drilling and factors affecting maximum force and torque. International Journal of Machine Tools and Manufacture, 46(1), 70-75. doi:10.1016/j.ijmachtools.2005.03.015Fernandes, M., & Cook, C. (2006). Drilling of carbon composites using a one shot drill bit. Part II: empirical modeling of maximum thrust force. International Journal of Machine Tools and Manufacture, 46(1), 76-79. doi:10.1016/j.ijmachtools.2005.03.016Feito, N., Diaz-Álvarez, A., Cantero, J. L., Rodríguez-Millán, M., & Miguélez, H. (2015). Experimental analysis of special tool geometries when drilling woven and multidirectional CFRPs. Journal of Reinforced Plastics and Composites, 35(1), 33-55. doi:10.1177/0731684415612931Feito, N., Díaz-Álvarez, J., Díaz-Álvarez, A., Cantero, J., & Miguélez, M. (2014). Experimental Analysis of the Influence of Drill Point Angle and Wear on the Drilling of Woven CFRPs. Materials, 7(6), 4258-4271. doi:10.3390/ma7064258Iliescu, D., Gehin, D., Gutierrez, M. E., & Girot, F. (2010). Modeling and tool wear in drilling of CFRP. International Journal of Machine Tools and Manufacture, 50(2), 204-213. doi:10.1016/j.ijmachtools.2009.10.004Abrão, A. M., Rubio, J. C. C., Faria, P. E., & Davim, J. P. (2008). The effect of cutting tool geometry on thrust force and delamination when drilling glass fibre reinforced plastic composite. Materials & Design, 29(2), 508-513. doi:10.1016/j.matdes.2007.01.016Rawat, S., & Attia, H. (2009). Wear mechanisms and tool life management of WC–Co drills during dry high speed drilling of woven carbon fibre composites. Wear, 267(5-8), 1022-1030. doi:10.1016/j.wear.2009.01.031Fernández-Pérez, J., Cantero, J. L., Díaz-Álvarez, J., & Miguélez, M. H. (2017). Influence of cutting parameters on tool wear and hole quality in composite aerospace components drilling. Composite Structures, 178, 157-161. doi:10.1016/j.compstruct.2017.06.043Tsao, C. C., & Hocheng, H. (2007). Effect of tool wear on delamination in drilling composite materials. International Journal of Mechanical Sciences, 49(8), 983-988. doi:10.1016/j.ijmecsci.2007.01.001Chen, W.-C. (1997). Some experimental investigations in the drilling of carbon fiber-reinforced plastic (CFRP) composite laminates. International Journal of Machine Tools and Manufacture, 37(8), 1097-1108. doi:10.1016/s0890-6955(96)00095-8Murphy, C., Byrne, G., & Gilchrist, M. D. (2002). The performance of coated tungsten carbide drills when machining carbon fibre-reinforced epoxy composite materials. Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture, 216(2), 143-152. doi:10.1243/0954405021519735Fernández-Pérez, J., Cantero, J., Díaz-Álvarez, J., & Miguélez, M. (2019). Hybrid Composite-Metal Stack Drilling with Different Minimum Quantity Lubrication Levels. Materials, 12(3), 448. doi:10.3390/ma12030448Tsao, C. ., & Hocheng, H. (2004). Taguchi analysis of delamination associated with various drill bits in drilling of composite material. International Journal of Machine Tools and Manufacture, 44(10), 1085-1090. doi:10.1016/j.ijmachtools.2004.02.019Palanikumar, K., Prakash, S., & Shanmugam, K. (2008). Evaluation of Delamination in Drilling GFRP Composites. Materials and Manufacturing Processes, 23(8), 858-864. doi:10.1080/10426910802385026Mohan, N. S., Kulkarni, S. M., & Ramachandra, A. (2007). Delamination analysis in drilling process of glass fiber reinforced plastic (GFRP) composite materials. Journal of Materials Processing Technology, 186(1-3), 265-271. doi:10.1016/j.jmatprotec.2006.12.043Srinivasa Rao, B., Rudramoorthy, R., Srinivas, S., & Nageswara Rao, B. (2008). Effect of drilling induced damage on notched tensile and pin bearing strengths of woven GFR-epoxy composites. Materials Science and Engineering: A, 472(1-2), 347-352. doi:10.1016/j.msea.2007.03.023Enemuoh, E. U., El-Gizawy, A. S., & Chukwujekwu Okafor, A. (2001). An approach for development of damage-free drilling of carbon fiber reinforced thermosets. International Journal of Machine Tools and Manufacture, 41(12), 1795-1814. doi:10.1016/s0890-6955(01)00035-9Saravanan, M., Ramalingam, D., Manikandan, G., & Kaarthikeyen, R. R. (2012). Multi Objective Optimization of Drilling Parameters Using Genetic Algorithm. Procedia Engineering, 38, 197-207. doi:10.1016/j.proeng.2012.06.027Feito, N., Milani, A. S., & Muñoz-Sánchez, A. (2015). Drilling optimization of woven CFRP laminates under different tool wear conditions: a multi-objective design of experiments approach. Structural and Multidisciplinary Optimization, 53(2), 239-251. doi:10.1007/s00158-015-1324-yKrishnaraj, V., Prabukarthi, A., Ramanathan, A., Elanghovan, N., Senthil Kumar, M., Zitoune, R., & Davim, J. P. (2012). Optimization of machining parameters at high speed drilling of carbon fiber reinforced plastic (CFRP) laminates. Composites Part B: Engineering, 43(4), 1791-1799. doi:10.1016/j.compositesb.2012.01.007Krishnamoorthy, A., Rajendra Boopathy, S., Palanikumar, K., & Paulo Davim, J. (2012). Application of grey fuzzy logic for the optimization of drilling parameters for CFRP composites with multiple performance characteristics. Measurement, 45(5), 1286-1296. doi:10.1016/j.measurement.2012.01.008Abhishek, K., Datta, S., & Mahapatra, S. S. (2014). Optimization of thrust, torque, entry, and exist delamination factor during drilling of CFRP composites. The International Journal of Advanced Manufacturing Technology, 76(1-4), 401-416. doi:10.1007/s00170-014-6199-3El Kadi, H. (2006). Modeling the mechanical behavior of fiber-reinforced polymeric composite materials using artificial neural networks—A review. Composite Structures, 73(1), 1-23. doi:10.1016/j.compstruct.2005.01.020Altinkok, N., & Koker, R. (2004). 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