Results 251 to 260 of about 13,241 (300)

Object shape virtualization in impedance tomography

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, 2009
PurposeThe purpose of this paper is to introduce a method for increasing imaging quality in impedance tomography. The paper presents an optical method of shape virtualization, processing algorithm draft and results of virtualization for sample objects.Design/methodology/approachIn impedance tomography the image reconstruction algorithms must yield ...
Tomasz Grzywacz, Jan Sikora, Stefan Wójtowicz   +2 more
openaire   +1 more source

Virtual Impedance Method for Mutual Coupling Compensation

IEEE Transactions on Antennas and Propagation, 2021
The radiation pattern of an antenna within an array environment is modified by mutual coupling to neighboring elements, which can create unknown phase and amplitude variation on the order of 10° and 5 dB. This uncertainty in the element patterns results in beamforming errors, which can be particularly problematic for applications requiring precise ...
Carl Pfeiffer, Fikadu Dagefu, Boris Tomasic, Jeffrey N. Twigg, Bae-Ian Wu   +4 more
openaire   +1 more source

Virtual Impedance Analyzer Design and Implementation

Second International Conference on Innovative Computing, Informatio and Control (ICICIC 2007), 2007
In this research, the structure and design of virtual impedance analyzers are studied. The construction process is also described and introduced. This programmable virtual impedance analyzer is achieved by software part, Labview, hardware part, DAQ card and some external circuits.
Kai-chao Yao, Chin-wen Liao, Li-ling Chao, Fu-yu Lin   +3 more
openaire   +1 more source

An Islanding Microgrid Power Sharing Approach Using Enhanced Virtual Impedance Control Scheme

IEEE Transactions on Power Electronics, 2013
In order to address the load sharing problem in islanding microgrids, this paper proposes an enhanced distributed generation (DG) unit virtual impedance control approach. The proposed method can realize accurate regulation of DG unit equivalent impedance
Jinwei He, Yun Wei Li, Josep M Guerrero
exaly   +2 more sources

Virtual Impedance Adaptive Study of Parallel Virtual Synchronous Generators

2019 22nd International Conference on Electrical Machines and Systems (ICEMS), 2019
As the increasing of the capacity of the micro grid, it is difficult for a single VSG-controlled inverter to meet the requirements of micro grid use. VSG operating in parallel has become the main solution, and the problem of equalization in the division has naturally become the focus of research.
Chunxue Wen, Yaozhi Huang, Qi Xiong
openaire   +1 more source

Virtual Impedance Design Considerations for Virtual Synchronous Machines in Weak Grids

IEEE Journal of Emerging and Selected Topics in Power Electronics, 2020
Most renewable energy sources (RESs) are interfaced to electricity grids via voltage-source converters (VSCs). To facilitate the integration, the controllers based on the emulation of synchronous generators have been increasingly used. This control technique is commonly referred to as Virtual Synchronous Machine (VSM) and recent studies have shown that
Alberto Rodriguez-Cabero, Javier Roldan-Perez, Milan Prodanovic   +2 more
openaire   +1 more source

Virtual Impedance Control for Safe Human-Robot Interaction

Journal of Intelligent & Robotic Systems, 2015
Collision avoidance is essential for safe robot manipulation. Especially with humans around, robots should work only when safety can be robustly guaranteed. In this paper, we propose using virtual impedance control for reactive, smooth, and consistent collision avoidance that interferes minimally with the original task.
Sheng-Yen Lo, Ching-An Cheng, Han-Pang Huang   +2 more
openaire   +1 more source

A Control Method for Parallel Inverter with Adaptive Virtual Impedance

2018 5th International Conference on Systems and Informatics (ICSAI), 2018
Aiming at the influence that the difference of line impedance of multi-inverter parallel system to accuracy of uniform power distribution in system, this paper proposes a control method based on adaptive virtual impedance and variable droop coefficient. Based on the research of adaptive virtual impedance link, variable droop coefficients control method
Ben Nie, Xiangming Li
openaire   +1 more source

Virtual Biopsies in Barrett's Esophagus Using an Impedance Probe

Annals of the New York Academy of Sciences, 1999
Abstract: Preliminary results of electrical impedance measurements in squamous and columnar epithelia in rat and human tissues are presented. The aim of this work is to show the possibility of differentiating these two types of epithelia in terms of their electrical characteristics. For the measurements, we employed a 1.95m‐long, 3.2‐mm‐diameter, four‐
C A, González-Correa, B H, Brown, R H, Smallwood, N, Kalia, C J, Stoddard, T J, Stephenson, S J, Haggie, D N, Slater, K D, Bardhan   +8 more
openaire   +2 more sources

Control of mobile manipulator using a virtual impedance wall

Proceedings 2002 IEEE International Conference on Robotics and Automation (Cat. No.02CH37292), 2003
We present a method for controlling mobile manipulators for assist systems. The mobile manipulator should provide good manipulability and stability at any time. Most of mobile assist systems have a heavy mobile base for stability. We propose an approach for motion control of a mobile manipulator to remove unnecessary movement of the mobile base. In our
Tomohito Takubo, Hirohiko Arai, Kazuo Tanie   +2 more
openaire   +1 more source