79 research outputs found
Bioethics as mental health? the core response on typhoon rai in southern leyte, philippines
Super Typhoon Rai recently devastated the Philippines in December of 2021 and consequently disrupted its public and mental health interventions. With glocality standing at the interface between the global and the local, the objective of the study is to gather the core mental health response of those affected by the Typhoon in the province of Southern Leyte. As a methodology, the paper utilized face-to-face and online qualitative investigation from selected key informants in the province’s towns and islands. The paper is significant since it aims to add to the existing discussion from a province not reported in recent literature from disasters. This study preliminarily enables the emergence of glocal emergency bioethics as a link to disaster mental health
Prediction of attenuated guided waves propagation in carbon fiber composites using Rayleigh damping
In this work, a predictive model of attenuated guided wave propagation in carbon fiber–reinforced polymer using Rayleigh damping is developed. After a brief introduction, this article reviews the theory of guided waves in anisotropic composite materials. It follows with a discussion of the piezoelectric wafer active sensors, which are lightweight and inexpensive transducers for structural health monitoring applications. Experiments were performed on a carbon fiber–reinforced polymer panel to measure the dispersion curves and the piezoelectric wafer active sensors tuning curves. Lamb wave damping coefficient was modeled using the multi-physics finite element method and compared with experimental results. A discussion about the capability to simulate, with multi-physics finite element method commercial software, guided wave in composite material using the Rayleigh damping is developed. This article ends with conclusion, and suggestions for further work are also presented
Guided Wave Propagation in Composite Laminates Using Piezoelectric Wafer Active Sensors
Piezoelectric wafer active sensors (PWAS) are lightweight and inexpensive transducers that enable a large class of structural health monitoring (SHM) applications such as: (a) embedded guided wave ultrasonics, i.e., pitch-catch, pulse-echo, phased arrays; (b) high-frequency modal sensing, i.e., electro-mechanical impedance method; and (c) passive detection. The focus of this paper is on the challenges posed by using PWAS transducers in the composite laminate structures as different from the metallic structures on which this methodology was initially developed. After a brief introduction, the paper reviews the PWAS-based SHM principles. It follows with a discussion of guided wave propagation in composites and PWAS tuning effects. Then, the mechanical effect is discussed on the integration of piezoelectric wafer inside the laminate using a compression after impact. Experiments were performed on a glass fibre laminate, employing PWAS to measure the attenuation coefficient. Finally, the paper presents some experimental and multi-physics finite element method (MP-FEM) results on guided wave propagation in composite laminate specimens
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