Search results: Found 255

Listing 1 - 10 of 255 << page
of 26
>>
Sort by
Electrical Resistivity and Conductivity

Author:
ISBN: 9789535131854 9789535131861 Year: Pages: 124 DOI: 10.5772/65130 Language: English
Publisher: IntechOpen
Subject: Electrical and Nuclear Engineering
Added to DOAB on : 2019-10-03 07:51:50

Loading...
Export citation

Choose an application

Abstract

Motivated by the importance of electrical resistivity and conductivity, important experts in this field grasp most recent researches in this book. It addresses recent advances in electrical resistivity and conductivity modelling, measurement, estimation and sensing methods and implications. This book introduces innovative case studies for ""Electrical Resistivity Sensing Methods and Implications"", ""Resistivity Model of Frozen Soil and High-Density Resistivity Method for Exploration of Discontinuous Permafrost"", ""Measurement of Electrical Resistivity for Unconventional Structures"", ""Estimation of Hydrological Parameters from Geoelectric Measurements"" and ""Assessment of Cryoprotectant Concentration by Electrical Conductivity Measurement and Its Applications in Cryopreservation"". These recent advances are well prepared and presented in six chapters. These chapters are carefully selected to reflect current variable techniques, new concepts and methods related to the book's topic from different perspectives.

Simulation and Modelling of Electrical Insulation Weaknesses in Electrical Equipment

Author:
ISBN: 9781789237689 9781789237696 Year: Pages: 214 DOI: 10.5772/intechopen.72459 Language: English
Publisher: IntechOpen
Subject: Computer Science
Added to DOAB on : 2019-10-03 07:51:52

Loading...
Export citation

Choose an application

Abstract

Around 80% of electrical consumption in an industrialised society is used by machinery and electrical drives. Therefore, it is key to have reliable grids that feed these electrical assets. Consequently, it is necessary to carry out pre-commissioning tests of their insulation systems and, in some cases, to implement an online condition monitoring and trending analysis of key variables, such as partial discharges and temperature, among others. Because the tests carried out for analysing the dielectric behaviour of insulation systems are commonly standardised, it is of interest to have tools that simulate the real behaviour of those and their weaknesses to prevent electrical breakdowns. The aim of this book is to provide the reader with models for electrical insulation systems diagnosis.

Optimization and Control of Electrical Machines

Authors: --- ---
ISBN: 9781789234527 9781789234534 Year: Pages: 98 DOI: 10.5772/intechopen.71523 Language: English
Publisher: IntechOpen
Subject: Mechanical Engineering
Added to DOAB on : 2019-10-03 07:51:51

Loading...
Export citation

Choose an application

Abstract

Electrical machines are used in the process of energy conversion in the generation, transmission and consumption of electric power. In addition to this, electrical machines are considered the main part of electrical drive systems. Electrical machines are the subject of advanced research. In the development of an electrical machine, the design of its different structures is very important. This design ensures the robustness, energy efficiency, optimal cost and high reliability of the system. Using advanced techniques of control and new technology products has brought electrical machines into their optimal functioning mode. Different techniques of control can be applied depending on the goals considered. The aim of this book is to present recent work on the design, control and applications of electrical machines.

Electrical Power and Energy Systems for Transportation Applications

Authors: ---
ISBN: 9783038422426 9783038422075 Year: Pages: XX, 572 DOI: 10.3390/books978-3-03842-207-5 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Chemical Technology
Added to DOAB on : 2017-07-26 13:30:46
License:

Loading...
Export citation

Choose an application

Abstract

Electrical power and energy systems are at the forefront of application developments in renewable energy, smart grids, electric aircrafts, electric and hybrid vehicles and much more. The associated technologies and control methods are crucial to achieving global targets in energy efficiency and low-carbon operations, and will also contribute to key areas such as energy security. The greatest challenges occur when we combine new technologies at large-scale and often complex system level. The Special Edition will cover theoretical developments with special emphasis on applications in electrical power and energy systems. Topics covered include:Renewable Energy Systems: Energy management; hybrid systems; distributed systems; renewable sources and integration; transient energy storage, charging networks.Electrical Machines, Drives and Applications: AC and DC machines and drives; multiscale systems modeling; remote monitoring and diagnosis; electric and hybrid vehicles; energy conversion, vehicle to grid interaction.Power Electronic Systems: Converters and emerging technologies; modeling simulation and control; power factor correction; power supplies; active filters; reliability and fault tolerance.Electrical Power Generation Systems: Modeling and simulation of electrical power systems; load management; power quality; distribution reliability; distributed and islanded power systems, sensor networks, communication and control.Electrical Power Systems Modeling and Control: Modeling and control methodologies and applications; intelligent systems; optimization and advanced heuristics; adaptive systems; robust control.

Soft Magnetic Composites in Novel Designs of Electrical Traction Machines

Author:
ISBN: 9783731506195 Year: Pages: ix, 267 p. DOI: 10.5445/KSP/1000064348 Language: ENGLISH
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:02:01
License:

Loading...
Export citation

Choose an application

Abstract

Nowadays, the manufacturing of electrical machines based on electrical steel laminations has been well established worldwide. Compared with the electrical steel, the soft magnetic composites (SMC) shows magnetic isotropy and lower eddy current losses. Thus, it becomes an important impulse promoting the development of new topologies of electrical machine. The application of SMC in the electrical traction machine for hybrid electrical vehicle or electrical vehicle has been researched in the work.

Nano- and Microcomposites for Electrical Engineering Applications

ISBN: 9783038422921 9783038422938 Year: Pages: XVI, 286 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Chemistry (General)
Added to DOAB on : 2016-12-05 09:48:54
License:

Loading...
Export citation

Choose an application

Abstract

In a dedicated Special Issue, the journal Polymers has compiled papers on the current trends and research directions within the preparation, characterization and application of polymer-based composite materials in electrical engineering applications. In recent times, this type of material has evolved to become one of the most thoroughly investigated materials, stimulated by the demand for the resource-efficient assembly of generators, transformers, communication devices, etc. Novel composites are to be used as insulating materials with high thermal conductivity and excellent temperature stability, through which premature ageing and degradation of devices shall be avoided or at least reduced. This Special Issue comprises twelve contributions by internationally renowned researchers; to mention Petru V. Nothinger (University Politehnica of Bucharest), Alun S. Vaughan (University of Southampton), Stanislaw M. Gubanski (Chalmers University of Technology), Michael Muhr (Graz University of Technology), Johan J. Smit (TU Delft), and Ulf W. Gedde (KTH Royal Institute of Technology) as prominent examples. The state-of-the-art research and technology of the area ‘micro- and nanocomposites for electrical engineering applications’ has been summarized in three review articles, while the current research trends and the development and characterization of novel materials have been described in eight original research articles. Stimulated by the vivid current interest in this topic, this Special Issue of Polymers has additionally been compiled in a book version.

Charge Carrier Dynamics in Organometal Halide Perovskite Probed by Time-Resolved Electrical Measurements (Book chapter)

Author:
ISBN: 9789535122456 Year: DOI: 10.5772/61631 Language: English
Publisher: IntechOpen Grant: FP7 Ideas: European Research Council - 226136
Subject: Science (General)
Added to DOAB on : 2019-01-17 11:48:00
License:

Loading...
Export citation

Choose an application

Abstract

This chapter presents the fate of the charge carriers from the moment of its photogeneration in the perovskite to injection and transport into electrodes. Time-resolved electrical measurement techniques, terahertz (THz) spectroscopy and microwave (MW) conductivity, are primarily used to deconvolute ultrafast processes and to directly access behavior of charged species from the ps to µs timescales. Transient absorption and photoluminescence spectroscopy were also utilized to gain insight on carrier population dynamics and radiatively recombining charges. Photogenerated charged species were converted into highly mobile charges (µe = 12.5 cm2V-1s-1 and µh = 7.5 cm2V-1s-1) almost instantaneously (< 0.2 ps), while the remaining loosely bounded excitons dissociate into mobile charges after 2-3 ps. This high mobility is maintained for at least 1 ns as obtained by THz spectroscopy, while its lifetime is at least few tens of µs as measured by the MW conductivity technique. Lowering the temperature increases carrier mobilities with T-1.6.Dependence and a 75 meV barrier energy is required for temperature-activated recombination. Finally, injection of hole from MAPbI3 to Spiro-OMeTAD was found to be ultrafast and the state and population of dark holes dictate its recombination.

Electrical-field sensitive YBa?Cu?O??? detectors for real-time monitoring of picosecond THz pulses

Author:
Book Series: Karlsruher Schriftenreihe zur Supraleitung / Hrsg. Prof. Dr.-Ing. M. Noe, Prof. Dr. rer. nat. M. Siegel ISSN: 18691765 ISBN: 9783731507864 Year: Volume: 21 Pages: XIV, 199 p. DOI: 10.5445/KSP/1000081476 Language: ENGLISH
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:02:01
License:

Loading...
Export citation

Choose an application

Abstract

This work investigates the capability of the high-temperature superconductor YBCO to sense the evolution of the electrical field of THz pulses. A deposition process for ten unit-cell thin films and a sub-µm patterning process were developed to enable high sensitivities. The detector response to THz exctiations and its electrical-field sensitivity were studied. This unique characteristic allows for the investigation of instabilities of the THz radiation emitted from synchrotron storage rings.

Structure-Related Intrinsic Electrical States and Firing Patterns of Neurons With Active Dendrites

Author:
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889456086 Year: Pages: 296 DOI: 10.3389/978-2-88945-608-6 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Neurology
Added to DOAB on : 2019-01-23 14:53:43
License:

Loading...
Export citation

Choose an application

Abstract

Activity of the multi-functional networked neurons depends on their intrinsic states and bears both cell- and network-defined features. Firing patterns of a neuron are conventionally attributed to spatial-temporal organization of inputs received from the network-mates via synapses, in vast majority dendritic. This attribution reflects widespread views of the within-cell job sharing, such that the main function of the dendrites is to receive signals and deliver them to the axo-somatic trigger zone, which actually generates the output pattern. However, these views are now revisited due to finding of active, non-linear properties of the dendritic membrane practically in neurons of practically all explored types. Like soma and axon, the dendrites with active membrane are able to generate self-maintained, propagating depolarizations and thus share intrinsic pattern-forming role with the trigger zone. Unlike the trigger zone, the dendrites have complex geometry, which is subject to developmental, activity-dependent, or neurodegenerative changes. Structural features of the arborization inevitably impact on electrical states and cooperative behavior of its constituting parts at different levels of organization, from sub-trees and branches to voltage- and ligand-gated ion channels populating the dendritic membrane. More than two decades of experimental and computer simulation studies have brought numerous phenomenological demonstrations of influence of the dendritic structure on neuronal firing patterns. A necessary step forward is to comprehend these findings and build a firm theoretical basis, including quantitative relationships between geometrical and electrical characteristics determining intrinsic activity of neurons. The articles in this eBook represent progress achieved in a broad circle of laboratories studied various aspects of structure and function of the neuronal dendrites. The authors elucidate new details of dendritic mechanisms underlying intrinsic activity patterns in neurons and highlight important questions that remain open in this important domain of cellular and computational neuroscience.

Inter-cellular Electrical Signals in Plant Adaptation and Communication

Authors: --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889455218 Year: Pages: 120 DOI: 10.3389/978-2-88945-521-8 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Botany --- Physiology
Added to DOAB on : 2019-01-23 14:53:42
License:

Loading...
Export citation

Choose an application

Abstract

Plants use the Sun's energy to synthesize the basic biomolecules that make up all the organic matter of all organisms of terrestrial ecosystems, including ourselves. Therefore, understanding their adaptive mechanisms to variations of environmental factors, both biotic and abiotic, is fundamental, and particularly relevant in the current context of rapid climate change. Some of the most important adaptive mechanisms of plants are the electrical and chemical signaling systems for the exchange of information between proximally and distally located cells. These signalling systems allow plants to dynamically coordinate the activities of all cells under a diversity of situations. In this Research Topic, we present eight articles that bring up new hypothesis and data to understand the mechanisms of systemic electrical signaling and the central role that it plays in adapting the whole plant to different stresses, as well as new findings on intracellular calcium and nitric oxide-based signaling pathways under stress, which could be extrapolated to non-plant research.

Listing 1 - 10 of 255 << page
of 26
>>
Sort by