Low Resistance Polycrystalline Diamond Thin Films Deposited by Hot Filament Chemical Vapour Deposition

Polycrystalline diamond thin films with outgrowing diamond (OGD) grains were deposited onto silicon wafers using a hydrocarbon gas (CH4) highly diluted with H2 at low pressure in a hot filament chemical vapour deposition (HFCVD) reactor with a range of gas flow rates. X-ray diffraction (XRD) and SEM showed polycrystalline diamond structure with a random orientation. Polycrystalline diamond films with various textures were grown and (111) facets were dominant with sharp grain boundaries. Outgrowth was observed in flowerish character at high gas flow rates. Isolated single crystals with little openings appeared at various stages at low gas flow rates. Thus, changing gas flow rates had a beneficial influence on the grain size, growth rate and electrical resistivity. CVD diamond films gave an excellent performance for medium film thickness with relatively low electrical resistivity and making them potentially useful in many industrial applications

Surface Electromyography for Direct Vocal Control

This paper introduces a new method for direct control using the voice via measurement of vocal muscular activation with surface electromyography (sEMG). Digital musical interfaces based on the voice have typically used indirect control, in which features extracted from audio signals control the parameters of sound generation, for example in audio to MIDI controllers. By contrast, focusing on the musculature of the singing voice allows direct muscular control, or alternatively, combined direct and indirect control in an augmented vocal instrument. In this way we aim to both preserve the intimate relationship a vocalist has with their instrument and key timbral and stylistic characteristics of the voice while expanding its sonic capabilities. This paper discusses other digital instruments which effectively utilise a combination of indirect and direct control as well as a history of controllers involving the voice. Subsequently, a new method of direct control from physiological aspects of singing through sEMG and its capabilities are discussed. Future developments of the system are further outlined along with usage in performance studies, interactive live vocal performance, and educational and practice tools

Operational transresistance amplifier based PID controller

This paper presents Operational transresistance amplifier (OTRA) based proportional-integral- derivative (PID) controller with independent electronic tuning of proportional, integral, and derivative constants. The configuration can be made fully integrated by implementing the resistors using matched transistors operating in the linear region. Theoretical propositions are verified through SPICE simulations using 0.18 µm process parameters from MOSIS (AGILENT). In order to demonstrate the workability of the proposed controller, its effect on step response of an OTRA based second order system is analyzed and presented

Analysis of current and potential sensor network technologies and their incorporation as embedded structural system

This document provides a brief overview of the actual wireless ad hoc sensor networks technologies and standards available, especially in view of their possible implementation for shipping container protection and monitoring within the framework of the STEC Action aiming at analyzing possible technical solutions to improve the security of the millions of containers moving in and out of Europe. Examples of applications and research projects are reported from the literature to give insights on the possibility of implementation of wireless sensor networks in real world scenarios.JRC.G.5-European laboratory for structural assessmen

Dynamic Tuning MQP

Cyther V3 looks to improve Cyther V2, a mechatronic string instrument equipped with ten strings and a set of solenoids to actuate the strings. The goal of this project was to create a next generation Cyther equipped with a system that can autonomously tune each string during a performance, expanding on the types of musical expressions Cyther V2 was capable of. The tuning system senses string tension, estimates pitch, adjusts the tension, and corrects for errors in estimation using optical pickups. The frequency analysis accuracy and speed, and the tuning accuracy and speed of the new autonomous tuning system was analyzed for a single string to determine the quality of the new autonomous tuning system...

Biology Inspired Approach for Communal Behavior in Sensor Networks

Research in wireless sensor network technology has exploded in the last decade. Promises of complex and ubiquitous control of the physical environment by these networks open avenues for new kinds of science and business. Due to the small size and low cost of sensor devices, visionaries promise systems enabled by deployment of massive numbers of sensors working in concert. Although the reduction in size has been phenomenal it results in severe limitations on the computing, communicating, and power capabilities of these devices. Under these constraints, research efforts have concentrated on developing techniques for performing relatively simple tasks with minimal energy expense assuming some form of centralized control. Unfortunately, centralized control does not scale to massive size networks and execution of simple tasks in sparsely populated networks will not lead to the sophisticated applications predicted. These must be enabled by new techniques dependent on local and autonomous cooperation between sensors to effect global functions. As a step in that direction, in this work we detail a technique whereby a large population of sensors can attain a global goal using only local information and by making only local decisions without any form of centralized control

A Combination of Ion Implantation and High-Temperature Annealing: The Origin of the 265 nm Absorption in AlN

The commonly observed absorption around 265 nm in AlN is hampering the outcoupling efficiency of light-emitting diodes (LEDs) emitting in the UV-C regime. Carbon impurities in the nitrogen sublattice (CN) of AlN are believed to be the origin of this absorption. A specially tailored experiment using a combination of ion implantation of boron, carbon, and neon with subsequent high-temperature annealing allows to separate the influence of intrinsic point defects and carbon impurities regarding this absorption. Herein, the presented results reveal the relevance of the intrinsic nitrogen-vacancy defect VN. This is in contradiction to the established explanation based on CN defects as the defect causing the 265 nm absorption and will be crucial for further UV-LED improvement. Finally, in this article, a new interpretation of the 265 nm absorption is introduced, which is corroborated by density functional theory (DFT) results from the past decade, which are reviewed and discussed based on the new findings