für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The book focuses on electromagnetic absorbing and shielding properties of multilayer materials. Nanomaterials are widely used and composite materials` dielectric characterization is deeply discussed. Very little academic literature exists on how to model(design) an electromagnetic absorber using matrix formalism of microwave propagation through multilayer materials. This book therefore, provides an interesting approach to the absorber`s design in which different branches of science are applied and where all of them are used to optimize the `quasi perfect absorber`: nanotechnology, electromagnetic wave propagation theory, composite materials manufacturing, evolutionary computation. With respect to the present literature, the method presented in this book computes the absorbing capability of materials, taking into account for the reflection and transmission coefficients, considering also oblique incidence of the electromagnetic field. Theoretical modeling of absorbers is experimentally validated. At the end of the book the electromagnetic shielding performance of carbon-carbon material and of high weight percentage carbon nanotubes based composite materials are throughly analyzed. ····· 1036189325
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray It presents a basic meaning for the distribution networks in united systems including city power systems and their classification. All components are inserted & their logic is illustrated. Renewable energy support is proposed while most important factors are studied. Power factor, voltage drop, power loss and load curves (with harmonics) are analyzed however, the coding systems were presented in details. Two major examples as a project style have been investigated with results. LAN, fire fighting and Telephone wiring are accounted. ····· 1036189057
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Bangladesh lacks sufficient electricity generation capacity and electricity grid networks to electrify the whole nation and has never enjoyed 100% electrification. Currently, electricity generation per capita in Bangladesh is the lowest in the world, about 154 kWh/per year. There is a huge unmet commercial demand for energy as the shortfall of power generation capacity is estimated to be around 2500 MW for the next five years.A recent survey found only 32 percent of rural firms with access to electricity compared to 60 percent in urban areas. The Southern region, including Chittagong, accounts for another 20 percent. The rest is fairly evenly split among the western, northwestern, and central zones. Most generation plant, are also located close to Dhaka, with smaller plants near the gas fields or other load centers approximately 70 percent of overall transmission capacity is in the Dhaka region. Most reasonable forecasts suggest that Bangladesh would need at least one utility-scale plant in the 500 to 700 MW range every year to catch up with demand. But efficient incessant supply of electricity is an obligation for the balanced regional growth and development of Bangladesh. ····· 1036188743
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray A comparison of the radial distribution of output HPM power produced by a relativistic magnetron driven by a traditional solid cathode and recently invented transparent cathode was performed. The transparent cathode was found to improve relativistic magnetron operation by providing faster start of microwave oscillations at a predetermined mode without mode competition. Comparison of output microwave pulses produced by the microwave pulse compressor equipped with a mechanically operated switch and a fast gas-discharge switch showed that the latter one sufficiently shortens the rise time of the output microwave pulse. Results of this research suggest that: i) the use of a transparent cathode in relativistic and, probably, nonrelativistic magnetrons provides better mode selection by locking the desired magnetron oscillations in a shorter period of time, and ii) the use of a faster switch (as fast as possible) in a waveguide of a microwave pulse compressor shortens the rise time of the compressed output microwave pulse. ····· 1036188611
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This book represents different types of renewable energy, the behavior of renewable energy.The world is hunger of energy. The conventional energy is decreasing day by day. The use and necessity of renewable energy is discussed with respect to all over the world. A wind farm consists of several wind turbines.It is essential to connect the wind farm. Wind energy and wind firm are also discussed then it covers essential topics about wind turbine systems such as wind turbine generation system, wind power output, mechanical power extracted from wind.The speed of wind is not constant as well as the generated voltage is not also constant.Finally a wind farm integrated power system is designed and in simulation it is tried to keep the voltage constant by controlling the pitch angle of the wind turbine. ····· 1036188395
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Many developments in finite-difference time domain (FDTD) computational modelling of Maxwell s equations and computed tomography (CT) imagery have caused important progress in heat delivery method, temperature monitoring, and thermal dosimetry. Electromagnetic hyperthermia method in the treatment of cancer is an application which had been revealed by these developments. The objective of electromagnetic hyperthermia is to destroy the tumor or cancer cells by achieving the highest possible temperature in the tumor or cancer cells without exceeding 42ºC in the surrounding healthy tissues. Many studies have shown that high temperatures can damage and kill cancer cells. Electromagnetic field is supplied to induce a temperature increase on tumor or cancer cells. In this thesis, the electromagnetic power deposition within the discretized cells is observed by solving the Maxwell s equations with FDTD. Further the thermal process is investigated by solving the Pennes bio-heat transfer equation with finite difference method. Moreover, this thesis is serving as an introduction for electromagnetic hyperthermia in the human issues. To that end an extensive study is planned. ····· 1036187974
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray A repetitive control method for output voltage control of a three phase uninterruptible power supply (UPS) with isolation transformer is investigated. In the method voltage control loop is employed in the stationary dq frame. The controller eliminates the periodic errors on the output voltages due to inverter voltage nonlinearity and load disturbances. The controller design and implementation details are given. The controller is implemented on a 5-kVA UPS prototype which is constructed in laboratory. Linear and nonlinear loads for balanced and unbalanced load operating conditions are considered. The steady-state and dynamic performance of the control method are investigated in detail. The theory of the control strategy is verified by means of simulations and experiments. ····· 1036187942
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Different films of silicon oxynitride (SiOxNy) were grown using a glass-assisted CO2 laser technique. The samples were prepared on P- type silicon substrates (111) at temperatures from (750, 800, 850 oC) using two different gases of NH3 and O2 as the source of nitrogen and oxygen in open air. Fourier Transform Infrared (FTIR) Spectroscopy, Reflectometry, Spectroscopic Ellipsometry and C-V measurements were used for films characterization. FTIR spectra shows a strong stretching bond of Si-N at wave number range from (700-1000 cm-1) depending on the films composition, and Si-O stretching bond at wave number around (1088 cm1). The peak position and the corresponding full width at half maxima (FWHM) for Si-O stretching bond have been also analyzed. The Reflectometry was used to measure the refractive index which is equal to 1.66 for SiOxNy film growing at 750 oC. It was found that the samples are non uniform in their thickness (16-142 nm) and the refractive index of the films is graded (1.44-1.97) through the Spectroscopic Ellipsometry. The C-V characterization, dielectric constant and flat band voltage (VFB) were determined at high frequency of 1MHz. ····· 1036187892
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Magnetostatics of thin wires is a specific branch of theoretical physics. Its main equation always contains a source, which can only be an endless curve in form. The field of an arc, which has endpoints, is not defined, therefore, there exists only entire field of an entire endless wire. This feature of the subject does not allow to employ the method of Green`s functions, which requires that a wire is divided into small pieces. Therefore, only entire filed of an endless wire exists, therefore, such a wire plays the role of the `elementary` source. In this book an approach is outlined, which allows to construct magnetic fields of a quite broad variety of curves. ····· 1036187595
für 61.20€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Electromagnetic acoustic transducers (EMATs) are non-contact, non-destructive testing devices for conducting specimens. The efficiency of EMATs is inherently low and methods for increasing it have been the subject of intense research. In publications, the finite element (FE) technique has been applied to the diffusion equation in order to model EMATs. However, electromagnetic theory indicates that the diffusion equation must be solved for the magnetic vector potential (MVP) in conjunction with an equation for the total current. An existing FE formulation considering the two equations becomes unstable when modeling transient inputs in EMAT transmitters. The limitation posed by the instability prompted the development of an improved FE formulation, which solves the two equations and is suitable for the modeling of EMATs.The objective of the research work described in this thesis is to properly and accurately model EMATs, so that their efficiency could be improved at the design stage. The thesis describes the governing equations of EMATs, improved techniques for their solution, and the application of these techniques to the analysis of such devices. ····· 1036187487
für 53.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The capability of non-interfering measurements together with the vast range of detection schemes allows application of optical spectroscopy in a variety of experiments. The aim of this work was the development and application of some of these new spectroscopic methods for the study and diagnostics of gases and plasma. In the dielectric barrier discharge the interest was focused on the description of the excited electronic states population variations during the period of discharge by the use of the fast broad-band emission spectroscopy. The application of the Cavity ring-down spectrometer to detect the singlet oxygen in the microwave plasma afterglow is described as second application in plasma. In the field of new methods the work describes the development of a new laser source - Vertical external cavity surface emitting laser and of a small, fast, robust and low-cost NO2 and NO3 detector based on the Incoherent broad-band cavity enhanced absorption spectroscopy. The dissertation should be useful mainly for the readers thinking about the application of these methods in their experiments as well as to anyone who is interested to discover more about their physical background. ····· 1036187468
für 71.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This book, Nonlinear Interactions of femtosecond pulses with transparent media, is an attempt to disseminate few important results obtained recently that enables the readers to understand the rich physics involved in the light-matter interactions in femtosecond (fs) regime. With the high intensities available from fs laser pulses, the subject becomes much richer, as the pulse itself affects and is affected by the material it propagates through, in dramatic ways. Interactions representing both these classes form the subject of this book. Considering the vast nature of this subject we limit ourselves in this book to the second and third order nonlinear phenomena namely, supercontinuum generation, mulitphoton absorption and surface enahanced third order processes demonstrated with four-wave mixing at surfaces. ····· 1036187195
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Electrical mismatching losses in photovoltaic systems are of great interest to system designers. In this book, an adaptive photovoltaic (PV) system is proposed based on novel flexible switch matrixes that form different possible topologies. This system maximizes the generated power in real-time for utility interactive systems in a modified inverter configuration. The proposed system uses fewer components and achieves maximum efficiency during shading and module mismatches by reconfiguring the PV modules based on real-time solar insolation, current operational conditions, and maximum efficiency criterion. Simulation tools are used to demonstrate that the proposed topologies provide improvement in efficiency over existing traditional PV systems. Furthermore, a prototype has been designed and developed. Experimental results for efficiency comparison between traditional PV system configurations are described in this work. Potential improvement using the proposed adaptive configuration is analyzed. The overall results validate the adaptive system and its benefits for a wide range of applications. ····· 1036187160
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Modeling and design of a single photon detector and its various characteristics are presented. It is a type of avalanche photo diode (APD) designed to suit the requirements of a Quantum Key Distribution (QKD) detection system. The device is modeled to operate in a gated mode at liquid nitrogen temperature for minimum noise and maximum gain. Different types of APDs are compared for best performance. The APD is part of an optical communication link, which is a private channel to transmit the key signal. The encrypted message is sent via a public channel. The optical link operates at a wavelength of 1.55 m. The design is based on InGaAs with a quantum efficiency of more than 75% and a multiplication factor of 1000. The calculated dark current is below 10-12A with an overall signal to noise ratio better than 18dB. The device sensitivity is better than -40dBm, which is more than an order of magnitude higher than the dark current, corresponding to a detection sensitivity of two photons in pico-second pulses. ····· 1036187079
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Organic light emitting diode technology is evolving rapidly with commercial applications in recent years. OLED materials and design are moving into an advanced stage with optimising techniques becoming more important. This work presents the use of porphyrin materials for organic electronics, specifically for organic light emitting diodes using phosphorescent emission. The porphyrins show interesting photophysical properties which allow for an exploitation of the normally forbidden triplet energy states to achieve a significant enhancement in the device efficiency. This research presents a simple host-guest system where this concept is demonstrated. Various porphyrin structures are synthesised and tuned for OLED performance, from this, we can learn how chemical structure relates to the exciton dynamics and their resulting light emission. It is hoped that this work outlines a possible route to phosphorescent OLED technologies. ····· 1036187057
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray For taking into account electromagnetic wave propagation within a transformer a length unit inductance is proposed to be connected in series to the length unit turn-to-turn capacitance and a unit length inductance is proposed to be connected in series to the unit length layer-to-layer capacitance within the distributed and quasi distributed parameter model of transformers. As a result the model is able to take into account the wave propagation along the turn-to-turn and layer-to-layer capacitance current path of the coil. This model is able to meet the circuit regularity requirements as well. The quasi distributed parameter model contains several identical lumps for modelling the wave propagation but being easily applicable for the practical use with circuit simulator software. A high frequency model of transformer shielding is proposed for the use with circuit simulator software modelling the high frequency behaviour of the shielding. A comprehensive model containing the proposed elements can help in evaluating electromagnetic compatibility (EMC) of a future transformer during its design period. ····· 1036186995
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Due to some of their advantages, HVDC systems become more and more popular in power systems. Up to now, many HVDC models have been developing. Each HVDC model has its own function and control scheme base on purposes of application. Before practical application, these HVDC have to be tested for the feasibility of these HVDC models in term of technical criteria by using power system simulation programs such as Pss/e, EMTP and EMTDC. Pss/e is a popular commercial programme for power system simulation using RMS value. This paper will show you how to make an HVDC user defined model. The control scheme of the HVDC and the case study will be presented in this thesis. ····· 1036186856
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray The field of plasmonics has offered the promise to combine electronics and photonics at the nanometer scale for ultrafast information processing speeds and compact integration of devices. Various plasmonic waveguide schemes were proposed with the potential to achieve switching functionalities and densely integrated circuits using optical signals instead of electrons. Among these, the hybrid plasmonic waveguide stands out thanks to two sought-out properties: long propagation lengths and strong modal confinement. In this work, hybrid plasmonic waveguides and passive devices were theoretically investigated and experimentally demonstrated on an integrated silicon platform. A thin silicon dioxide gap between a gold conductive layer and a silicon core provides subwavelength confinement of light inside the gap. A long propagation length of 40 m was experimentally measured. A system of taper coupler connects the plasmonic waveguide to conventional photonic waveguides at a high efficiency of 80%. Passive devices were also fabricated and characterized, including S-bends and Y-splitters. ····· 1036186809
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray In the time of current trend of increasing energy consumption, the wind-power engineering may compensate considerable part of required electric energy. Rapid wind-power engineering development is considered to be one of the important sources of human need satisfaction. Conventional wind turbine control strategies are dedicated to ensure high energy conversion efficiency under varying wind conditions. The challenge in wind power control engineering is to design an adaptive wind turbine control strategy, which provides the dynamic system stability and the effectiveness of energy conversion. The aim of this book is to design and implement the control algorithm, which implies the electromagnetic torque control in order to adapt the rotor speed and keep high energy conversion efficiency. Wind turbine operation is considered in the partial-load regime. The stability of the purposed control system is studied using linear control theory concepts. The effectiveness of the wind energy conversion is proved by the simulation results in MATLAB Simulink environment. ····· 1036186722
für 44.10€ kaufen ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Advanced epitaxial techniques such as molecular beam epitaxy or metal-organic chemical vapour deposition have made it possible to grow interfaces between two semiconductors flat up to one atomic monolayer. The possibility of fabricating a heterostructure of strictly-defined parameters, a quasi-two-dimensional nature and sharp density of states, has stimulated both theoretical and experimental research and shortly found many applications including LEDs, lasers, high electron mobility transistors, IR photodetectors, etc. In this work a detailed study of optical properties of excitons in double quantum wells subject to magnetic and electric fields is presented. Starting from the well-known Luttinger formulae we developed an efficient way to solve the Schrödinger equation of a coulombically-bound pair electron-hole forming an exciton. The results are illustrated on relevant figures, giving an opportunity to better understand the effects of external fields on the studied system. The book should shed light on methods used for calculations of magnetooptical properties and may be useful to anyone who is interested in theoretical or experimental research on semiconductor quantum structures. ····· 1036186562
····· lezzter Preis 49.50€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Ausführlich und exakt präsentiert Otto Henker einen für Studieneinsteiger konzipierten Einblick in die Brillenlehre. Auf Grundlage seiner Vorlesungen und in gut verständlicher Sprache gibt der angesehene Jenaer Professor zunächst einen Überblick über die physikalischen Eigenschaften des Lichts und des menschlichen Auges an sich, bevor er anhand zahlreicher Abbildungen minutiös die Beschaffenheit und Anwendung diverser Brillentypen und -gläser erläutert. Nach wie vor ein Standardwerk für angehende Optiker.Otto Henker war Anfang der 1920er Jahre Mitbegründer des Optischen Museums in Jena und förderte die Entstehung der dortigen Optikerschule. Zudem arbeitete er als Leiter der Abteilung medizinisch-optischer Geräte in den Jenaer Zeiss-Werken. ····· 1036174592
····· lezzter Preis 44.10€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Today the world is looking towards the efficient energy generation from renewable energy sources because of extinction of fossil fuels.Wind energy is a promising source of green energy.But the problem associated with this kind of energy id due to varying wind speeds the out put is also varying so it is not possible to integrate it to grid.Here Induction generators are dominantly used because of their advantages in variable speed torque characteristics.In this book an attempt is made to discuss different types of generators used in wind energy and different topologies for control of voltage and frequency of Self Excited induction generator are discussed and new promising methods are proposed for low cost power generation. ····· 1036125963
····· lezzter Preis 71.10€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray This book has investigated radioclimatological study in a clear-air environment as applicable to terrestrial line of sight link design problems. Radioclimatological phenomena are adequately reviewed both for the precipitation effect and clear-air effect. The research focuses more on the clear-air effect of radioclimatological studies. Two Southern African countries chosen for case study in the report are Botswana and South Africa. To this end, radiosonde data gathered in Maun, Botswana and Durban, South Africa are used for model formulation and verification. The data used in the book ranges from three years to ten years in these two stations. Three to ten years of refractivity data gathered in Botswana and South Africa is used for the model formulation. On the other hand, eight months signal level measurement data recorded from the terrestrial line of sight link set up between Howard College and Westville Campuses of the University of KwaZulu-Natal, Durban South Africa is used for model verification. ····· 1036125488
····· lezzter Preis 53.10€ ···· Rheinberg-Buch.de - Bücher, eBooks, DVD & Blu-ray Spintronics is an area of electronics that studies the design of electronic devices based on the spin properties of electrons, taking advantage of their full potential. To date, despite the extended theoretical work done on this class of components, models are mainly physical and, due to their extreme complexity, cannot be implemented in circuit simulators. The aim of this work is to address the critical problems of modeling spintronic devices in a compact form. The main goal is to make a bridge between a purely physical description and a more electrical counterpart of spintronic elements in order to enable their use in Computer Assisted Design tools, just as for CMOS devices. The first part of the book gives an introduction to the different kinds of spin-orbit interactions, the materials used for realizing spintronic devices and the main spin-based devices currently developed. The second part is then dedicated to the modeling of simple transistor structures where the current depends on spin-polarized carriers. Moreover, a brief outlook on possible future spintronic devices is given. ····· 1036125431· 1 ·· 2 ·· 3 ·· 4 ·· 5 ·· 6 ·· 7 ·· 8 ·· 9 ·
Affiliate Marketing
AdHoc MeldungenAffiliate & PublisherAdvertiser & MerchantAcademyAntwortenArtikelsucheAdventskalender
AffilitivProduktdatenPreisvergleich
