The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The present study examined how the expression of enhanced green fluorescent protein (eGFP) and human cardiac actin (ACTC) in zebrafish Danio rerio influences embryonic heart rate (RH) and the swim performance and metabolic rate of adult fish. Experiments with the adults involved determining the critical swimming speed (Ucrit, the highest speed sustainable and measure of aerobic capacity) while measuring...
Diffusion equation based modeling has been proposed for mapping the reverberant component of the electromagnetic field in enclosures at high frequencies. Preliminary evaluation of the electromagnetic diffusion model using a dimensional reduction approach showed promising results compared to measurements. Here we develop a full three-dimensional diffusion model of the experimental canonical test cases...
It is important when considering the shielding effectiveness (SE) of an enclosure to take into account any contents the enclosure may have. Contents such as printed circuit boards (PCBs) will absorb electromagnetic energy and so affect the SE of the enclosure. Previously, it has been shown that the absorption cross section (ACS) of PCBs and the transmission cross section of apertures can be used in...
The errors, due to stair-cased meshing, in the Shielding Effectiveness (SE) of cavities modelled with thin boundaries, in the Finite-Difference Time-Domain (FDTD) method, are examined. The errors in SE are found to be associated with the error in the surface area of the cavity caused by the use of a stair-cased mesh. An empirical solution is demonstrated, which improves the stair-cased model accuracy...
In reverberant electromagnetic environments such as reverberation chambers, shielding enclosures, vehicles and buildings, the electromagnetic energy density is often assumed to be uniform and the direction of arrival of electromagnetic waves (Poynting vector) and their polarisation is assumed uniformly distributed. This is the basis of the power balance method for electromagnetic coupling analysis...
We present a new face centered approach to the collocation of the fields for the application of a surface impedance boundary condition (SIBC). This approach deals with the ambiguities in the surface normal that arise at the edges on stair-cased surfaces.. The accuracy of the new scheme is compared to edge based and conformal approaches using both planar sheet and spherical shell test cases. Stair-casing...
Shielding effectiveness (SE) is an important measure of how well an enclosure reduces the electromagnetic (EM) field incident upon it. Commonly, when the shielding effectiveness of an enclosure is stated it is for the case when the enclosure is empty. Including contents such as printed circuit boards (PCBs) in the enclosure will affect the shielding effectiveness as the PCB absorbs EM energy. One...
Knowledge of the absorption cross section (ACS) of a printed circuit board (PCB) is essential when defining an enclosure's shielding effectiveness as it will determine how a PCB affects the internal electromagnetic (EM) field inside the enclosure. In this paper we show how the ACS changes when a PCB is in the vicinity of the enclosure walls by making measurements in a small reverberation chamber....
This paper describes work undertaken to understand how the structure of a nonwoven carbon fibre material determines its shielding effectiveness, including the effects of fibre orientation, and contact resistance. In order to facilitate understanding of the material behaviour, software has been written to generate Monte Carlo Models (MCMs) of the material structure. The results of our MCMs are compared...
The electromagnetic environment inside an equipment enclosure at high frequencies is strongly dependent on the absorption of energy by the contents. This effect is neglected by current shielding measurement standards. Here we extended the concept of shielding measurements using surrogate “representative contents” proposed at lower frequencies into the regime were the enclosure is electrically large...
The Absorption Cross Section (ACS) of Printed Circuit Boards (PCBs) can be used to help determine how PCBs affect the internal electromagnetic (EM) field in a shielded enclosure and thus the enclosure shielding effectiveness. Stacked PCBs inside densely populated enclosures may not have the same ACS as the sum of the individual PCBs due to ‘shadowing’ effects. In this paper ACS measurement results...
The plane-wave shielding effectiveness of conductive non-woven fabrics is dominated by the sheet conductance over a wide range of frequencies until the effects of skin depth, and apertures start to influence the performance (typically at 1–10 GHz depending on the areal density). This paper describes models for determining the sheet conductance from knowledge of the type, quantity, orientation and...
This paper describes a cost-efficient Intentional EMI Detection system and gives a brief overview of the identification and location system being developed as part of the STRUCTURES project.
This paper describes the effect of high temperature ageing on the electromagnetic emissions of a number of PIC microcontrollers. The aged devices show a measureable shift in the frequency of emissions. Shift in the voltage-current characteristics of the device output pins has also been observed.
This paper considers the shielding effectiveness of nonwoven materials in the 1–8.5 GHz range using parametric semi-empircal models and experimental techniques. A range of materials based on metalised carbon fibres are considered with weights between 10 and 75 g/m², thicknesses between 50 and 400μm, and measured shielding effectiveness between 35 and 100dB. A numerical model is presented and compared...
A novel design for a dual mode antenna, intended for use in reverberation chambers, is evaluated numerically using method-of-moments simulations. The transition region between a low frequency monopole mode and a high frequency exponential taper mode in the band 200 MHz to 1 GHz is investigated and the basic design of the antenna is shown to be near optimal for a lower operational frequency of 200...
In this paper, a Genetic Algorithm (GA) is used to build macro models of small structures, such as joints and apertures, for use in large-scale computer simulations for aircraft electromagnetic compatibility (EMC) testing and certification. The field penetrating the structure is approximated by radiated fields of electric and magnetic dipole moment array. A GA is applied to determine the dipole moment...
This paper provides an example of a reverberant environment application. A metallic box in different configurations has been simulated with CST STUDIO SUITE™ and the calculated results have been compared to measurements.
This paper describes a methodology for the construction of macro models of small structures used in large-scale simulations for aircraft electromagnetic compatibility (EMC) testing and certification. The methodology aims to provide macro-model parameters using field transformation of data obtained from detailed simulation or measurement of the feature of interest. This paper concentrates on the measurement...
Welcome to York and welcome to EMC Europe 2011. I hope you have a fruitful and successful conference and that you enjoy your stay in our historic city.
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.