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GNSS Antenna Caused Near-Field Interference Effect in Precise Point Positioning Results

/GLONASS observations from ASG-EUPOS network, Artificial Satellites , 49(4), 211-223. Dilßner F., Seeber G. Wübbena G., Schmitz M. (2008). Impact of Near-Field Effects on the GNSS Position Solution, Proceedings ION GNSS-08, Savannah, Georgia. Georgiadou Y., Kleusberg A. (1988). On carrier Signac signal multipath effects in relative GPS positioning, Manuscripta Geodaetica , 13, 172-179. Granström C., Johansson J. (2007). Site Dependent Effects in High-Accuracy Applications of GNSS. Proceedings of the Symposium of the IAG Subcommission for Europe (EUREF), June 6

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Numerical Simulations of Blast Loads from Near-Field Ground Explosions in Air

äggblad H., Numerical simulations of blast loads and structural deformation from near-field explosions in air , International Journal of Impact Engineering, 2011, 38, 597–612. [5] J ohnson G.R., C ook W.H., A constitutive model and data for metals subjected to large strains, high strain rates and high temperatures , Proceedings of the 7th International Symposium on Ballistics, The Hague, The Netherlands, 23 Apr. 1983. [6] F lis L., S perski M., Badania odporności osłon warstwowych zbudowanych ze stali kadłubowych na ostrzał pociskami 12,7 mm , ZN AMW

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Dipole Near Field Analysis – A Closed Form Calculation in Cartesian Coordinates

Abstract

This article deals with analytical calculation of the near-field of an electric dipole in Cartesian coordinate system in a closed form. Results of the analytical calculation are verified by numerical method.

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Exposimetric Characterization of the Near-Field of a Portable Transceiver Emitting in the Ultrahigh Frequency Range and Simulation of the Electromagnetic Power Deposited in a Ferrimagnetic Biological Tissue Present in Such a Field

Abstract

A portable radiocommunication device usually face-held during its use was chosen for characterizing its electromagnetic near-field distribution in air. Set to emit on a frequency of 440 MHz for digital voice communication with a maximum input power of 5 W, its antenna parameters were analyzed and the maps of field strengths were depicted up to distances of 20 cm from the device by using of a dual-sensor exposimeter. Since the occupational exposure safety limit for incident field levels was exceeded closer than 12 cm from the transceiver (for the magnetic field component), it became interesting to quantify the power loss in an alleged case of a brain containing also magnetite particles. Up to the present, only the electric field component was of interest when investigating biological effects of such exposures. With the new evidence from 2016, that human brain contains four orders of magnitude more magnetite nanocrystals than it was known before, a question rises in connection to the magnetic response of tissues impinged by fields with significant magnitudes and covering the hundreds of MHz frequency range. Starting from this question, we set-up a simulation in which a tissue with ferromagnetic content was mimicked for initial dosimetric computations

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Investigating the Performance of Viscoelastic Dampers (VED) Under Nearfield Earthquakes with Directivity Feature

. - LAI, M. L.: Seismic Behavior of Steel Frame with Added Viscoelastic Dampers. Journal of Structural Engineering, ASCE, Vol. 121, Iss. 10, 1995, pp. 1418 - 1426. [10] Iranian code of practice for seismic resistant design of buildings standard (4th ed.), 2015, Tehran: BHRC. [11] VATANSHENAS, A.: Investigation of PTMD system affected by Parkfield near-field Earthquake. Journal of Modern Applied Science, Vol. 11, Iss. 4, 2017, pp. 70 - 79.

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Using Persistence Spectrum for Realistic Exposure Assessment to Time Varying Radiofrequency Signals

., Bragard G., Picard D. and Chauvin S., Mobile telephones: A comparison of radiated power between 3G VoIP calls and 3G VoCS calls, Journal of Exposure Science and Environmental Epidemiology (2015) 25, pp. 80–83 [5] Paljanos, A., Miclăuș, S., Bechet, P., &Munteanu, C. (2016). Assessment of mobile phone user exposure to UMTS and LTE signals: comparative near-field radiated power levels for various data and voice application services. Journal of Electromagnetic Waves and Applications, 30(9), 1101–1115. https://doi.org/10.1080/09205071.2016.1167634 [6

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Shielding Efficiency of a Fabric Based on Amorphous Glass-Covered Magnetic Microwires to Radiation Emitted by a Mobile Phone in 2G and 3G Communication Technologies

Abstract

A dual band mobile phone model was used to check the shielding properties of an amorphous ferromagnetic textile against the radiation emitted by the handset. Two frequencies belonging to the 2nd and 3rd generation of mobile emission technologies were used, 897 MHz and 1950 MHz. The specific absorption rate (SAR) of energy deposition in a human head phantom was measured in standardized conditions. The textile contained micrometric-diameter wires of a ferromagnetic mixture embedded in a thin glass coat and weaved in a specific way. A set of fabric orientations and configurations (layering) were provided in the experiment in order to achieve a better shielding to the phone’s radiation. Compared with the non-shielded handset, SAR deposited in the head while using the fabric-covered phone could be decreased up to 30 % of its initial value – in case of 2G technology and up to 24 % – in case of 3G technology. This type of material shows one of the highest shielding efficiencies of the electric-field component in near-field exposure conditions reported until now. A cubic curve of SAR decrease in depth of the head was revealed in both uncovered and covered handset, the effect of shielding being larger at the higher frequency.

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Characterizing and Testing a Fabric Containing Amorphous Glass-Coated Ferromagnetic Microwires for its Magnetic and Electric Shielding Properties in the Frequency Range (1-3) Ghz

Abstract

By applying a non-standardized methodology and by using electric- and magnetic-field probes of small dimensions (< 1cm), we experimentally characterized the electromagnetic shielding properties of a fabric containing ferromagnetic microwires weaved on a single direction. Electronic microscopy and X-ray spectroscopy revealed the structure, dimensions and chemical elements content of the amorphous magnetic material. Electric shielding factor proved to be very low in the investigated frequency range, but magnetic shielding factor was high, especially when the weaving direction of the magnetic wires corresponded to the polarization direction of the emitting antenna, and showed some resonances. The magnetic shielding efficiency, if checked against an increasing incident magnetic flux density, proved not to change up to 200 nT. The investigated fabric have been previously proved to be very efficient in shielding the field emitted by a mobile phone in its near field, but present results show that near and far field shielding properties are different.

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A New Approach for Acoustic Field Interpolation

. 5. http://www.bksv.com/ 6. Kim, B. K., J. G. Ih. On the Reconstruction of Vibro-Acoustic Field over the Surface Enclosing an Interior Space Using the Boundary Element Method. – Journal of the Acoustical Society of America, Vol. 100 , 1996, No 5, pp. 3003-3016. 7. Schuhmacher, A., J. Hald, K. B. Rasmussen, P. C. Hansen. Sound Source Reconstruction Using Inverse Boundary Element Calculations. – Journal of the Acoustical Society of America, Vol. 113 , 2003, No 1, pp. 114-126. 8. Hald, J. Patch Near-Field Acoustical Holography Using a New

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Vibration-based Key Exchange among Multiple Smart Devices on the Desk

References [1] Diffie, W., Hellman, M. (1976). New directions in cryptography. IEEE transactions on Information Theory , 22(6), 644–654 [2] Gu, W., Yang, Z., Shangguan, L., Ji, X., Zhao, Y. (2014, September). ToAuth: Towards Automatic Near Field Authentication for Smartphones. In 2014 IEEE 13th International Conference on Trust, Security and Privacy in Computing and Communications (pp. 229–236). IEEE. [3] Halevi, T., Ma, D., Saxena, N., Xiang, T. (2012, September). Secure proximity detection for NFC devices based on ambient sensor data. In

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