| 1001. |
- Gustafsson, Mats, et al.
(författare)
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An overview of stored electromagnetic energy
- 2014
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Ingår i: Proceedings - 2014 International Conference on Electromagnetics in Advanced Applications, ICEAA 2014. - 9781467357104 ; , s. 793-795
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Konferensbidrag (refereegranskat)abstract
- Although, the stored electromagnetic energy of an antenna is used to determine the antenna Q, it is difficult to define the stored energy. The stored energy can be estimated from the input impedance of the antenna, the electromagnetic fields around the antenna, and the current densities in the antenna structure. These estimates are similar but not equal for all antennas. Here, the different approaches to determine the stored energy are discussed.
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| 1002. |
- Gustafsson, Mats, et al.
(författare)
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Antenna Q and Stored Energy Expressed in the Fields, Currents, and Input Impedance
- 2015
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Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X .- 1558-2221. ; 63:1, s. 240-249
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Tidskriftsartikel (refereegranskat)abstract
- Although the stored energy of an antenna is instrumental in the evaluation of antenna Q and the associated physical bounds, it is difficult to strictly define stored energy. Classically, the stored energy is either determined from the input impedance of the antenna or the electromagnetic fields around the antenna. The new energy expressions proposed by Vandenbosch express the stored energy in the current densities in the antenna structure. These expressions are equal to the stored energy defined from the difference between the energy density and the far field energy for many but not all cases. Here, the different approaches to determine the stored energy are compared for dipole, loop, inverted L-antennas, and bow-tie antennas. We use Brune synthesized circuit models to determine the stored energy from the input impedance. We also compare the results with differentiation of the input impedance and the obtained bandwidth. The results indicate that the stored energy in the fields, currents, and circuit models agree well for small antennas. For higher frequencies, the stored energy expressed in the currents agrees with the stored energy determined from Brune synthesized circuit models whereas the stored energy approximated by differentiation of input impedance gives a lower value for some cases. The corresponding results for the bandwidth suggest that the inverse proportionality between the fractional bandwidth and Q-factor depends on the threshold level of the reflection coefficient.
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| 1003. |
- Gustafsson, Mats, et al.
(författare)
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Physical Bounds and Optimal Currents on Antennas
- 2012
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Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X .- 1558-2221. ; 60:6, s. 2672-2681
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Tidskriftsartikel (refereegranskat)abstract
- Physical bounds on the directivity Q-factor quotient and optimal current distributions are determined for antennas of arbitrary shape and size using an optimization formulation. A variational approach offers closed form solutions for small antennas expressed in the polarizability of the antenna structure. Finite sized antennas are solved using Lagrangian parameters in a method of moments formulation. It is also shown that the optimal charge density for a small antenna can be generated by several current densities. Numerical examples for small and large antennas are used to illustrate the results.
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| 1004. |
- Gustafsson, Mats, et al.
(författare)
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Physical bounds on the partial realized gain
- 2010
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Ingår i: [Host publication title missing]. ; , s. 1-6
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Konferensbidrag (refereegranskat)abstract
- An antenna identity, derived from the forward scattering sum rule, shows that the partial realized gain of an antenna is related to the polarizability of the antenna structure. The partial realized gain contains the mismatch, directivity, efficiency, and polarization properties of the antenna. The antenna identity expresses how the performance depends on the electrical size and shape of the antenna structure. It is also the starting point for several antenna bounds. In this paper, the identity, its associated physical bounds, and computational aspects of the polarizability dyadics are discussed.
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| 1005. |
- Gustafsson, Mats, et al.
(författare)
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Stored electromagnetic energy and antenna Q
- 2015
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Ingår i: Progress In Electromagnetics Research. - 1070-4698 .- 1559-8985. ; 150, s. 13-27
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Tidskriftsartikel (refereegranskat)abstract
- Decomposition of the electromagnetic energy into its stored and radiated parts is instrumental in the evaluation of antenna Q and the corresponding fundamental limitations on antennas. This decomposition is not unique and there are several proposals in the literature. Here, it is shown that stored energy defined from the difference between the energy density and the far field energy equals the energy expressions proposed by Vandenbosch for many but not all cases. This also explains the observed cases with negative stored energy and suggests a possible remedy to them. The results are compared with the classical explicit expressions for spherical regions where the results only differ by the electrical size ka that is interpreted as the far-field energy in the interior of the sphere.
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| 1006. |
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| 1007. |
- Gustavsson, Elin, et al.
(författare)
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Surrogate antigens as targets for proteome-wide binder selection
- 2011
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Ingår i: New Biotechnology. - : Elsevier BV. - 1871-6784 .- 1876-4347. ; 28:4, s. 302-311
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Tidskriftsartikel (refereegranskat)abstract
- In the last decade, many initiatives have been taken to develop antibodies for proteome-wide studies, as well as characterization and validation of clinically relevant disease biomarkers. Phage display offers many advantages compared to conventional antibody generation by immunization and hybridoma technology, since it is an unlimited resource of affinity reagents without batch-to-batch variation and is amendable for high throughput. One of the major bottlenecks to proteome-wide binder selection is the limited supply of suitable target antigens representative of the human proteome. Here, we provide proof of principle of using easily accessible, cancer-associated protein epitope signature tags (PrESTs), routinely generated within the Human Protein Atlas project, as surrogate antigens in phage selectionsfor the retrieval of target specific binders. These binders were subsequently tested in western blot, immunohistochemistry and protein microarray application to demonstrate their functionality.
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| 1008. |
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| 1009. |
- Hagbert, Pernilla, Dr, 1986-, et al.
(författare)
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Contemporary Co-housing in Europe: Towards Sustainable Cities?
- 2020
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- This book investigates co-housing as an alternative housing form in relation to sustainable urban development. Co-housing is often lauded as a more sustainable way of living. The primary aim of this book is to critically explore co-housing in the context of wider social, economic, political and environmental developments. This volume fills a gap in the literature by contextualising co-housing and related housing forms. With focus on Denmark, Sweden, Hamburg and Barcelona, the book presents general analyses of co-housing in these contexts and provides specific discussions of co-housing in relation to local government, urban activism, family life, spatial logics and socio-ecology. This book will be of interest to students and researchers in a broad range of social-scientific fields concerned with housing, urban development and sustainability, as well as to planners, decision-makers and activists.
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| 1010. |
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