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Self-Powered Medical Devices for Vibration Suppression
No full textThis paper presents a non-invasive, self-powered system that can be used in the suppression of vibrations medically affecting people. Mechanical vibratory signals are picked up by piezoelectric sensors. Magnitude and frequency information is given as a voltage. Electronic circuitry filters, amplifies and gates the signal before either storing or manipulating and feeding the signal back to piezoelectric actuators, at the required phase and amplitude to suppress the vibrations. Outcomes of the paper show the use of different flexible piezoelectric materials to effectively increase energy storage and reduce vibrations.
Advances in low power electronics have provided a means of solely powering devices from piezoelectric harvested energy, especially with the advent of piezoelectric ceramic fibre composites. Energy harvesting has been implemented in hand cranked radios, shake powered flashlights, wind farms, and solar energy. Through the use of standard electronic techniques acquired power can be converted, stored and regulated. Piezoelectric fibre composites are capable of extracting energy from mechanical forces with the aim of collecting a portion of the mechanical energy associated with normal activates and utilising this in the creation of a self powered device to suppress low level vibrations
Modulation of size, shape and surface charge of chitosan nanoparticles with reference to antimicrobial activity
No full textChitosan is extensively used in medicine and medical textiles for drug delivery and other applications because of its biocompatibility, biodegradability and inherent antimicrobial properties. In this study, we demonstrated a manipulating route with suitable process conditions to synthesize chitosan nanoparticles which are expected to have the best antibacterial activity for medical application. Ionotropic cross-linking using sodium tripolyphosphate (TPP) was the chosen route for synthesis of chitosan nanoparticles. It was interesting to observe that pH of the chitosan and TPP solution has a significant role in controlling the nanoparticle shape and size and thus can be fine tuned to achieve optimum antimicrobial activity. Solution pH of both chitosan and TPP was demonstrated to be the most critical factor in controlling particle size, surface charge and even shape as revealed by the SEM and TEM micrograph. It was also found that variation in size, shape and surface charge of chitosan nanoparticles resulted in significant variation in their antibacterial activity. The study demonstrated that best antimicrobial activity against bacteria S. aureus was achieved when the chitosan nanoparticles were synthesized at chitosan solution pH fixed at 6.0 and the TPP solution pH at 8.9. These observations can be used to fine tune the synthesis of chitosan nanoparticles for their application as an effective antimicrobial agent in polymers and textiles for their noble use in medical field
Relaciones mediadas por el sonido entre jugadores en el entorno de juegos multijugador
No full textEste ensayo examina la relación entre el jugador y los efectos de sonido diegéticos en entornos de juego inmersivos para ordenadores, y a su vez, la manera en la que esta relación, en gran parte, pone en contexto al jugador dentro del mundo virtual del juego. Esta contextualización presupone una percepción basada principalmente en los sonidos de los objetos y los acontecimientos del mundo, lo que en el entorno del juego multijugador conduce finalmente a la comunicación entre los jugadores por medio del sonido diegético. El compromiso de los jugadores con - y la inmersión en - el ambiente acústico del juego es el resultado de una relación con el sonido mediada tecnológicamente. El motor del juego, por ejemplo, produce una gama de sonidos del entorno o del medio ambiente y casi todas las acciones del jugador tienen un sonido correspondiente. Una variedad de relevantes teorías y disciplinas, como la teoría del cine sonoro y la sonificación, se usan para construir nuestra base metodológica, y nos servimos de ejemplos como el del subgénero del «First-Person Shooter». Este tipo de juegos incluye las series «Doom» y «Quake», la serie «Half-Life» y sus derivados y juegos posteriores como «Left 4 Dead». La combinación del ambiente acústico, la posición interactiva del jugador - con la encarnación virtual de sus brazos protésicos - en el medio ambiente y las relaciones sonoras entre los jugadores produce la ecología acústica. Una exposición de esta comunicación multijugador, la ecología acústica resultante y la inmersión del jugador, es el objetivo principal del ensayo.This essay examines the relationship between player and diegetic sound FX in immersive computer game environments and how this relationship leads, in large part, to the contextualization of the player within the virtual world of the game. This contextualization presupposes a primarily sonically-based perception of objects and events in the world and, in a multi-player game, this ultimately leads to communication between players through the medium of diegetic sound. The players' engagement with, and immersion in, the game's acoustic environment is the result of a relationship with sound that is technologically mediated. The game engine, for example, produces a range of environmental or ambient sounds and almost every player action has a corresponding sound. A variety of relevant theories and disciplines are assessed for the methodological basis of the points raised, such as film sound theory and sonification, and, throughout, the First-Person Shooter sub-genre is used as an exemplar. Such games include the "Doom" and "Quake" series, the "Half-Life" series and derivatives and later games such as "Left 4 Dead". The combination of the acoustic environment, the interactive placement of the player - as embodied by his virtual, prosthetic arms - in the environment and the sonic relationships between players produces the acoustic ecology. An exposition of this multi-player communication and the resultant acoustic ecology and player immersion, is the main objective of the essay
Applying for research funding
No full textIn part 5 of a series on practical aspects of research, Jan Bogg, Maria Flynn and Julie Prescott outline some considerations for cardiovascular nurses to address when seeking funds for their research. They also offer general guidance to nurses planning to submit a grant application
'A pen man finds a use for every bit of wood': Fabians, leeks, carrots and spuds
No full textA short ethnographic study of an East Lancashire allotment site monitored and administrated by the Borough Council revealed a variety of activities partially related to self sufficiency. It is suggested that the approaches adopted by plot holders within a twenty-first century context reflect in many ways the early principles of collective socialism and the ownership of land by the public for the public good without the interference of private capitalism as advocated by the early Fabian Society pioneers. The study revealed plot holders reflected a diversity of socio-economic groups and there was a commonality of purpose and will to share produce and ideas. Cooperation not competition is the norm and the profit motive largely redundant and swamped by a shared perception of creating an environment conducive to well-being. Interviews revealed a high level of satisfaction in growing produce for themselves as well as other families, materials and resources shared without any anticipation or expectation of financial remuneration. It is argued such a context reflects the principles of the early Fabian movement for a reconstruction of society 'in accordance with the highest moral possibilities'. It is further argued that the context does not reflect a 'green' idyll for the middle classes adopting an alternative self sufficiency agenda but rather a small example of egalitarian agronomy
Grid Integration Strategy for Multifunctional Grid Front-End based Distributed Generation
No full textIn the future, distributed generation (DG) needs to be enabled to actively participate in control of grid voltage and frequency. An efficient grid integration strategy is required to interconnect the DG to conventional power systems and to improve the power quality and reliability (PQR) as well. The main task of the interconnected system is to control and maintain frequency and voltage of the power system in an acceptable range. This task has been currently operated using synchronous generators in many interconnected power systems. The power dispatch, frequency control and voltage control, power exchange and power optimization are already managed in conventional power supply systems. Therefore, the control strategy of the conventional power systems can be adapted to DG technologies through their interface unit to the grid, namely the inverter. The inverter is the primary interface unit between the energy source and the grid. This paper presents an adaptable and flexible control strategy for inverters as grid front-end based DG. The proposed control strategy can be a basic strategy to implement the DG system into existing conventional power systems
A Data Model for Describing and Exchanging Personal Achieved Learning Outcomes (PALO)
No full textEmployers seek people that match particular qualifications and graduates seek jobs that match their qualifications. This market is currently managed primarily using paper certificates and heterogeneous university management systems that capture achieved learning outcomes as well as corporate information systems that capture required qualifications. In light of trends toward increased student mobility, employability and lifelong learning, this situation is less than satisfactory. Therefore, in this paper, the authors propose a schema that facilitates interoperable storage and management of Personal Achieved Learning Outcomes (PALO) based on a common data model. This paper presents use case scenarios and implementations addressing these challenges and demonstrating the added value of using such a common model
Deus ex natura or non-stick pan? Competing discourses in Kenneth Grahame's The wind in the willows
No full textAluminum "Egg-Box" Panel as an Energy Absorber for Pedestrian Protection
No full textThis paper evaluates the quasi-static performance of lightweight aluminum "egg-box" panels which have an improved architecture specifically designed to increase the energy absorption capability. In its entirety, the egg-box panel structure investigated herein is made up of arrays of positive and negative frusta. To understand the collapse mechanism and the factors influencing the energy absorption thereof, compressive tests were conducted under similar test conditions on two single frusta, one constrained in situ and the other separated from the egg-box panel exposing the free free edges. Their load-displacement histories show characteristics that are similar, with a rise in load to a point where they plateau at a steady state load for the entire collapse time. But the energy absorbed by the in situ constrained frustum is 80% greater than that separated from the egg-box panel with free free edges