Revista Jurídica Digital UANDES
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Electrical & Mechanical Diagnostic Indicators of Wind Turbine Induction Generator Rotor Faults
No full textIn MW-sized wind turbines, the most widely-used generator is the wound rotor induction machine, with a partially-rated voltage source converter connected to the rotor. This generator is a significant cause of wind turbine fault modes. In this paper, a harmonic time-stepped generator model is applied to derive wound rotor induction generator electrical & mechanical signals for fault measurement, and propose simple closed-form analytical expressions to describe them. Predictions are then validated with tests on a 30 kW induction generator test rig. Results show that generator rotor unbalance produces substantial increases in the side-bands of supply frequency and slotting harmonic frequencies in the spectra of current, power, speed, mechanical torque and vibration measurements. It is believed that this is the first occasion in which such comprehensive approach has been presented for this type of machine, with healthy & faulty conditions at varying loads and rotor faults. Clear recommendations of the relative merits of various electrical & mechanical signals for detecting rotor faults are given, and reliable fault indicators are identified for incorporation into wind turbine condition monitoring systems. Finally, the paper proposes that fault detectability and reliability could be improved by data fusion of some of these electrical & mechanical signals
Exploring the holistic customer experience gestalt through its dimensions: a literature review
No full textCustomer experience is a focal topic for academics and practitioners, and has become a broad overarching construct within services and customer oriented research paradigms. However, customer experience research remains fragmented, lacking empirical grounding to its definition. A more complete customer experience definition could be better achieved by studying its component dimensions collectively and empirically. This review attempts to identify studies which contribute to the meaning of customer experience through: (i) consideration of its component dimensions, (ii) analysis of the different conceptualizations of these definitions and (iii) their empirical underpinnings.Since its conception three decades ago, customer experience has had five main types of dimensions associated to its composition (‘social’, ‘physical’, ‘sensorial’, ‘emotional’, and ‘cognitive’). These define customer experience conceptually but lack significant empirical grounding, motivating this review, and aiming to establish whether we can further refine our understanding of customer experience.A literature search was conducted pertaining to customer experience and its dimensions analysing the different conceptualizations of its meaning and empirical foundations. Using Scopus, Ebsco, and Google Scholar, journal articles and proceedings were gathered with the following terms and their synonyms: customer experience / engagement and the five dimensions. This work attempts to view customer experience through the lens of its dimensions thus each study was reviewed for its contribution to each dimension. Initial results will be discussed showing the identification of more than five dimensions with a lack of consistency in the terminology used to describe them and a limited number of empirical studies on the dimensions of customer experience, grounded in differing research disciplines.This review attempts to contribute to customer experience theory by identifying the extent of the empirical foundations of its dimensions. Practically this study will engage customer experience managers and executives by illustrating how they might better address customer experience from a better understanding of its constituent dimensions, and how the latter collectively makes up their customers holistic experience.This paper opens the door to more research into measuring and truly understanding the customer experience dimensions collectively. Theoretically more studies should consider the psychological roots of all the dimensions and explore the relevance of any additional ones. With advances in data analysis, and the greater understanding of, (i) the definitions of the dimensions of customer experience and (ii) their interaction and overlapping nature; new methodologies could be developed around verified models of the dimensions in order to provide a better understanding of customer experience.<br/
Enhancement of electrical conduction and phonon scattering in Ga<sub>2</sub>O<sub>3</sub>(ZnO)<sub>9</sub>-In<sub>2</sub>O<sub>3</sub>(ZnO)<sub>9</sub> compounds by modification of interfaces at the nanoscale
No full textResponse to: Prediction Models of Functional Outcomes for Individuals in the Clinical High-Risk State for Psychosis or With Recent-Onset Depression - A Multimodal, Multisite Machine Learning Analysis
No full textSimulation of fast space charge packets
No full textThe movement of space charge packets has been reported in polyethylene and epoxy resin under high electric fields by several groups, and has been characterized by the speed of propagation. A number of explanations of the formation and transport of slow space charge packets has been proposed.However, the mechanisms creating fast space charge packets are not clear. Dissado et al have suggested that the formation of fast charge packets is due to discontinuous electromechanical compression and charge injection at the electrode-insulation interface, and the transport of charge packets is related tocorresponding relaxation processes. In that model, charges travel in packets because of group polarization. This paper gives an alternative model considering the reduction of charge carrier activation energy due to charge density triggered polymer chain movement and subsequent chain relaxation times. It is shownthat the generation and transport of fast charge pulses are readily simulated by a bipolar charge transport model with three additional parameters: reduced activation energy, a charge density threshold, and a polymer chain relaxation time
Miniature Inspection Robot for Restricted Access eXploration (MIRRAX)
No full textThe MIRRAX remote inspection vehicle has been developed to explore and characterise enclosed legacy facilities on the Sellafield site which have limited access ports. Its reconfigurable design means that it can be deployed through a 150 mm port before changing its footprint shape to provide a stable platform for mobile characterisation. It can support both geometric and radiometric scanning
EURYPTERIDS FROM THE SILURIAN OF LESMAHAGOW HELD IN THE DONCASTER MUSEUM AND ART GALLERY
No full textA rediscovered collection of two dozen eurypterid fossil specimens, assigned to Slimonia acuminata and Erettopterus bilobus, is held in the Doncaster Museum and Art Gallery. The specimens are from the historically important Late Silurian Lesmahagow inlier of Lanarkshire, Scotland and are described herein. The material ranges from partial to complete specimens, with a wide range in size of both genera. Most specimens have either no or minimal damage. Some interesting features include the orientation and preservation of the eurypterids. Interestingly, the majority of the pterygotid specimens have their chelicerae attached to the body
Identification of Graphite Mechanical Behaviour & Dislocations by micro-Raman Microscopy
No full textUsing micro-Raman microscopy, we present graphite mechanical behaviour through the evolution of dislocation defect density and the resultant deformation (strain) in graphite components. The strengthening of the Raman-active G and D phonon modes observed in Raman spectrum under loading condition is attributed to an increase in number of dislocations in graphite structure. Increasing Raman peaks (IG & ID) strength linked with a generous number of dislocations indicates the potential capability of the Raman spectroscopy technique required to develop a mechanistic understanding of the complex mechanical behaviour of graphite for use in many industries and applications. Identification of deformation behaviour and a dislocation-mediated deformation process in graphite is the ultimate aim of our research to develop a better understanding of the graphite mechanical behaviour, important to clean nuclear fission energy technologies
