Current conserving theory for frequency dependent noise power under dc bias

We have analyzed the spatio-temporal patterns of current self-oscillation under DC bias and terahertz frequency-dependent nonlinear dynamics in semiconducting single-walled zigzag carbon nanotubes (CNTs). It is found that different transport states, including periodic and chaotic, appear with the influence of an external AC signal. The global transitions between periodic and chaotic states are clearly resolved from Poincaré bifurcation diagram. When the driving frequency is fixed at inverse golden mean ratio times natural frequency, the nonlinear CNT system exhibits a more complex transition behavior than at other driving frequencies.

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INVESTIGATION OF THE EFFECTS OF DC BIAS ON SINGLE-PHASE SHELL TYPE TRANSFORMERS USING FREQUENCY-DEPENDENT RELUCTANCE BASED MODEL

IEEE Transactions on Magnetics ◽

10.1109/tmag.2021.3093697 ◽

2021 ◽

pp. 1-1

Author(s):

Sevket Canturk ◽

Murat E. Balci ◽

M. Hakan Hocaoglu ◽

A. Kerem Koseoglu

Keyword(s):

Single Phase ◽

Frequency Dependent ◽

Shell Type ◽

Dc Bias

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Comparison of DCO-OFDM, ADO-OFDM, HDC-OFDM and HNC-OFDM for Optical Wireless Communications

Journal of Optical Communications ◽

10.1515/joc-2018-0073 ◽

2018 ◽

Vol 0 (0) ◽

Cited By ~ 1

Author(s):

M. Rubaiyat Hossain Mondal

Keyword(s):

Orthogonal Frequency Division Multiplexing ◽

Peak Power ◽

Average Power ◽

Noise Power ◽

Optical Wireless ◽

Optical Wireless Communications ◽

Bias Level ◽

Dc Bias ◽

Optical Ofdm ◽

Hybrid Diversity

Abstract This paper presents a new form of orthogonal frequency division multiplexing (OFDM) termed as hybrid noise cancelled asymmetrically clipped optical OFDM (HNC-OFDM) for optical wireless communication. This HNC-OFDM is formed by combining the concepts of noise cancelled asymmetrically clipped optical OFDM and DC biased optical OFDM (DCO-OFDM). HNC-OFDM has the same bit error rate (BER) performance and dimming flexibility but less complexity compared to the recently developed hybrid diversity combined OFDM. The optimum DC bias level for HNC-OFDM, DCO-OFDM and asymmetrically clipped DC biased optical OFDM is shown to depend on the target BER, the constellation size, the received signal to noise power ratio, the proportion of DCO-OFDM element, the link type, equalization, etc. Simulations results show that with an optimum bias, HNC-OFDM can outperform others in an average power limited channel, while DCO-OFDM is a better choice for a peak power limited channel.

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Ultimate resolution and information in electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100086787 ◽

1991 ◽

Vol 49 ◽

pp. 496-497

Author(s):

D. Van Dyck

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Transfer Function ◽

Information Transfer ◽

Communication Channel ◽

Structural Information ◽

Information Rate ◽

Noise Power ◽

Signal Power ◽

Imaging Device

An (electron) microscope can be considered as a communication channel that transfers structural information between an object and an observer. In electron microscopy this information is carried by electrons. According to the theory of Shannon the maximal information rate (or capacity) of a communication channel is given by C = B log2 (1 + S/N) bits/sec., where B is the band width, and S and N the average signal power, respectively noise power at the output. We will now apply to study the information transfer in an electron microscope. For simplicity we will assume the object and the image to be onedimensional (the results can straightforwardly be generalized). An imaging device can be characterized by its transfer function, which describes the magnitude with which a spatial frequency g is transferred through the device, n is the noise. Usually, the resolution of the instrument ᑭ is defined from the cut-off 1/ᑭ beyond which no spadal information is transferred.

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Analysis of photographic emulsions for High-Voltage Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148095 ◽

1993 ◽

Vol 51 ◽

pp. 452-453 ◽

Cited By ~ 1

Author(s):

James R. Kremer ◽

Paul S. Furcinitti ◽

Eileen O’Toole ◽

J. Richard McIntosh

Keyword(s):

Electron Microscope ◽

Optical Density ◽

High Voltage ◽

Noise Power ◽

Limited Information ◽

Modulation Transfer ◽

Transmission Microscopy ◽

High Voltage Electron Microscopy ◽

Voltage Range ◽

Voltage Electron

Characteristics of electron microscope film emulsions, such as the speed, the modulation transfer function, and the exposure dependence of the noise power spectrum, have been studied for electron energies (80-100keV) used in conventional transmission microscopy. However, limited information is available for electron energies in the intermediate to high voltage range, 300-1000keV. Furthermore, emulsion characteristics, such as optical density versus exposure, for new or improved emulsions are usually only quoted by film manufacturers for 80keV electrons. The need for further film emulsion studies at higher voltages becomes apparent when searching for a film to record low dose images of radiation sensitive biological specimens in the frozen hydrated state. Here, we report the optical density, speed and relative resolution of a few of the more popular electron microscope films after exposure to 1MeV electrons.Three electron microscope films, Kodak S0-163, Kodak 4489, and Agfa Scientia 23D56 were tested with a JEOLJEM-1000 electron microscope operating at an accelerating voltage of 1000keV.

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Analysis of transients in frequency-dependent interconnections and planar circuits with nonlinear loads

IEE Proceedings H Microwaves Antennas and Propagation ◽

10.1049/ip-h-2.1992.0007 ◽

1992 ◽

Vol 139 (1) ◽

pp. 38 ◽

Cited By ~ 5

Author(s):

Q. Gu ◽

D.M. Sheen ◽

S.M. Ali

Keyword(s):

Nonlinear Loads ◽

Frequency Dependent ◽

Planar Circuits

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Erratum: Analysis of transients in frequency-dependent interconnections and planar circuits with nonlinear loads

IEE Proceedings H Microwaves Antennas and Propagation ◽

10.1049/ip-h-2.1992.0084 ◽

1992 ◽

Vol 139 (5) ◽

pp. 476

Author(s):

Q. Gu ◽

D.M. Sheen ◽

S.M. Ali

Keyword(s):

Nonlinear Loads ◽

Frequency Dependent ◽

Planar Circuits

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Analysis of magneto rheological elastomers for energy harvesting systems

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209350 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 439-446

Author(s):

Gildas Diguet ◽

Gael Sebald ◽

Masami Nakano ◽

Mickaël Lallart ◽

Jean-Yves Cavaillé

Keyword(s):

Magnetic Field ◽

Energy Harvesting ◽

Shear Strain ◽

Magnetic Induction ◽

Magnetic Particles ◽

Homogeneous Magnetic Field ◽

Electrical Signal ◽

Harvesting Systems ◽

Dc Bias ◽

Magneto Rheological

Magneto Rheological Elastomers (MREs) are composite materials based on an elastomer filled by magnetic particles. Anisotropic MRE can be easily manufactured by curing the material under homogeneous magnetic field which creates column of particles. The magnetic and elastic properties are actually coupled making these MREs suitable for energy conversion. From these remarkable properties, an energy harvesting device is considered through the application of a DC bias magnetic induction on two MREs as a metal piece is applying an AC shear strain on them. Such strain therefore changes the permeabilities of the elastomers, hence generating an AC magnetic induction which can be converted into AC electrical signal with the help of a coil. The device is simulated with a Finite Element Method software to examine the effect of the MRE parameters, the DC bias magnetic induction and applied shear strain (amplitude and frequency) on the resulting electrical signal.

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