Development of an acoustic measurement system of the Modulus of Elasticity in trees, logs and boards

The objective of this Bachelor’s Thesis is to develop a portable electronic device capable of quantifying the stiffness of the wood of standing trees, logs and boards using non-destructive testing (NDT) by means of acoustic wave analysis. As an indicator of stiffness, the Modulus of Elasticity (MOE) is used, a standard figure in the industry. This way, wood from forestry can be characterized and classified for different purposes. This Thesis is part of LIFE Wood For Future, a project of the University of Granada (UGR) financed by the European Union’s LIFE programme. LIFE Wood For Future aims to recover the cultivation of poplar (populus sp.) in the Vega de Granada, by proving the quality of its wood through innovative structural bioproducts. Recovering the poplar groves of Granada would have great benefits for the Metropolitan Area: creation of local and sustainable jobs, improvement of biodiversity, and increase in the absorption of carbon dioxide in the long term, helping to reduce the endemic air pollution of Granada. This Final Degree Project has been developed in collaboration with the ADIME research group of the Higher Technical School of Building Engineering (ETSIE) and the aerospace electronics group GranaSat of the UGR. The goal of the developed device, named Tree Inspection Kit (or TIK), is to be an innovative, portable and easy-to-use tool for non-destructive diagnosis and classification of wood by measuring its MOE. TIK is equipped with the necessary electronics to quantify the Time of Flight (ToF) of an acoustic wave that propagates inside a piece of wood. In order to do this, two piezoelectric probes are used, nailed in the wood and separated a given distance longitudinally. The MOE can be derived from the propagation speed of the longitudinal acoustic wave if the density of the is known. For this reason, this device has the possibility of connecting a load cell for weighing logs or boards to estimate their density. It also has an expansion port reserved for future functionality. A methodology based on the Engineering Design Process (EDP) has been followed. The scope of this project embraces all aspects of the development of an electronic product from start to finish: conceptualization, specification of requirements, design, manufacture and verification. A project of this reach requires planning, advanced knowledge of signal analysis, electronics, design and manufacture of Printed Circuit Boards (PCB) and product design, as well as the development of a firmware for the embedded system, based on a RTOS. Prior to the design of the electronics, a Reverse Engineering process of some similar products of the competition is performed; as well as an exhaustive analysis of the signals coming from the piezoelectric sensors that are going to be used, and the frequency response characterization of the piezoelectric probes themselves. This project has as its ultimate goal the demonstration of the multidisciplinary knowledge of engineering, and the capacity of analysis, design and manufacturing by the author; his skill and professionalism in CAD and EDA software required for these tasks, as well as in the documentation of the entire process.El presente Trabajo de Fin de Grado tiene como objetivo el desarrollo de un dispositivo electrónico portátil capaz de cuantificar la rigidez de la madera de árboles en pie, trozas y tablas usando ensayos no destructivos (Non-Destructive Testing, NDT) por medio del análisis de ondas acústicas. Como indicador de la rigidez se usa el Módulo de Elasticidad (MOE), una figura estándar en la industria. Este TFG forma parte de LIFE Wood For Future, un proyecto de la Universidad de Granada (UGR) financiado por el programa LIFE de la Unión Europea. LIFEWood For Future tiene como objetivo recuperar el cultivo del chopo (populus sp.) en la Vega de Granada demostrando la viabilidad de su madera a través de bioproductos estructurales innovadores. Recuperar las choperas de Granada tendría grandes beneficios para la zona del Área Metropolitana: creación de puestos de trabajo locales y sostenibles, mejora de la biodiversidad, e incremento de la tasa de absorción de dióxido de carbono a largo plazo, contribuyendo a reducir la contaminación endémica del aire en Granada. Este Trabajo de Fin de Grado se ha desarrollado con la colaboración del grupo de investigación ADIME de la Escuela Técnica Superior de Ingeniería de Edificación (ETSIE) y el grupo de electrónica aeroespacial GranaSat de la UGR. El objetivo del dispositivo, denominado Tree Inspection Kit (TIK), es ser una herramienta innovadora, portátil y fácil de usar para el diagnóstico y clasificación no destructiva de la madera por medio de su MOE. TIK está dotado de la electrónica necesaria para medir el tiempo de tránsito (ToF) de una onda acústica que se propaga en el interior de una pieza de madera. Para ello, se utilizan dos sondas piezoeléctricas clavadas en la madera y separadas longitudinalmente una distancia conocida. De la velocidad de propagación de la onda longitudinal se puede derivar el MOE, previo conocimiento de la densidad del material. Por ello, este dispositivo cuenta con la posibilidad de conectarle una célula de carga y pesar trozas o tablas para estimar su densidad. También tiene un puerto de expansión reservado para funcionalidad futura. Se ha seguido una metodología basada en el Proceso de Diseño de Ingeniería (Engineering Design Process, EDP), abarcando todos los aspectos del desarrollo de un producto electrónico de principio a fin: conceptualización, especificación de requisitos, diseño, fabricación y verificación. Un proyecto de este alcance requiere de planificación, conocimientos avanzados de análisis de señales, de electrónica, de diseño y fabricación de Placas de Circuito Impreso (PCB) y de diseño de producto, así como el desarrollo de un firmware para el sistema empotrado, basado en un RTOS. Previo al diseño de la electrónica, se realiza un proceso de Ingeniería Inversa (Reverse Engineering) de algunos productos similares de la competencia; al igual que un exhaustivo análisis de las señales provenientes de los sensores piezoeléctricos que van a utilizarse y la caracterización en frecuencia de las propias sondas piezoeléctricas. Este proyecto tiene como fin último la demostración de los conocimientos multidisciplinares propios de la ingeniería y la capacidad de análisis, diseño y fabricación por parte del autor; su habilidad y profesionalidad en el software CAD y EDA requerido para estas tareas, así como en la documentación de todo el proceso.Unión Europe

Clinical Implementation of Bone Regeneration and Maintenance

Bone healing and regeneration is a complex process that can become impaired by disease or the size of a bone fracture or defect. In these instances, bone grafting can be used to aid the regeneration process. Bone grafting materials can be divided into autologous, allogenic, xenogeneic, and alloplastic, and are used to fill the defect/fracture void, thereby providing stability and supporting the infiltration of surrounding bone. This book will cover the most important fundamentals of bone grafting and provide an overview of current and future trends in bone graft research. Over the course of this book, the reader will learn about the most recent advancements in bone tissue biomaterials, the different fabrication techniques of bone tissue scaffolds, and the interaction of bone graft implant materials with the body by their induced cell and tissue reactions. Overall, this book provides an insight into bone grafting and the requirements for successful bone regeneration

Visible Light Communication (VLC)

Visible light communication (VLC) using light-emitting diodes (LEDs) or laser diodes (LDs) has been envisioned as one of the key enabling technologies for 6G and Internet of Things (IoT) systems, owing to its appealing advantages, including abundant and unregulated spectrum resources, no electromagnetic interference (EMI) radiation and high security. However, despite its many advantages, VLC faces several technical challenges, such as the limited bandwidth and severe nonlinearity of opto-electronic devices, link blockage and user mobility. Therefore, significant efforts are needed from the global VLC community to develop VLC technology further. This Special Issue, “Visible Light Communication (VLC)”, provides an opportunity for global researchers to share their new ideas and cutting-edge techniques to address the above-mentioned challenges. The 16 papers published in this Special Issue represent the fascinating progress of VLC in various contexts, including general indoor and underwater scenarios, and the emerging application of machine learning/artificial intelligence (ML/AI) techniques in VLC

Imaging Sensors and Applications

In past decades, various sensor technologies have been used in all areas of our lives, thus improving our quality of life. In particular, imaging sensors have been widely applied in the development of various imaging approaches such as optical imaging, ultrasound imaging, X-ray imaging, and nuclear imaging, and contributed to achieve high sensitivity, miniaturization, and real-time imaging. These advanced image sensing technologies play an important role not only in the medical field but also in the industrial field. This Special Issue covers broad topics on imaging sensors and applications. The scope range of imaging sensors can be extended to novel imaging sensors and diverse imaging systems, including hardware and software advancements. Additionally, biomedical and nondestructive sensing applications are welcome

Symmetry in Chaotic Systems and Circuits

Symmetry can play an important role in the field of nonlinear systems and especially in the design of nonlinear circuits that produce chaos. Therefore, this Special Issue, titled “Symmetry in Chaotic Systems and Circuits”, presents the latest scientific advances in nonlinear chaotic systems and circuits that introduce various kinds of symmetries. Applications of chaotic systems and circuits with symmetries, or with a deliberate lack of symmetry, are also presented in this Special Issue. The volume contains 14 published papers from authors around the world. This reflects the high impact of this Special Issue

NASA patent abstracts bibliography: A continuing bibliography. Section 2: Indexes (supplement 04)

For abstract, see N74-20609

The 1992 4th NASA SERC Symposium on VLSI Design

Papers from the fourth annual NASA Symposium on VLSI Design, co-sponsored by the IEEE, are presented. Each year this symposium is organized by the NASA Space Engineering Research Center (SERC) at the University of Idaho and is held in conjunction with a quarterly meeting of the NASA Data System Technology Working Group (DSTWG). One task of the DSTWG is to develop new electronic technologies that will meet next generation electronic data system needs. The symposium provides insights into developments in VLSI and digital systems which can be used to increase data systems performance. The NASA SERC is proud to offer, at its fourth symposium on VLSI design, presentations by an outstanding set of individuals from national laboratories, the electronics industry, and universities. These speakers share insights into next generation advances that will serve as a basis for future VLSI design

NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 22)

Entries for over 4000 patents and patent applications citations for the period May 1969 through December 1982 are listed. Subject, invention, source, number, and accession number indexes are included

NASA patent abstracts bibliography: A continuing bibliography. Section 2: Indexes (supplement 46)

A subject index is provided for over 5600 patents and patent applications for the period May 1969 through December 1994. Additional indexes list personal authors, corporate authors, contract numbers, NASA case numbers, U.S. patent class numbers, U.S. patent numbers, and NASA accession numbers