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- Eriksson, Jörgen, et al.
(författare)
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Parallellpublicering av konferensartiklar : principer, tillämpningar och tillgänglighet i svenska publiceringsdatabaser
- 2012
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Projektets huvudsyfte har varit att undersöka kvalitetsgranskade konferensartiklars tillgänglighet samt konferensers OA- och publiceringspolicies för att på så sätt klarlägga olika aspekter vad det gäller parallellpublicering i svenska publiceringsdatabaser. För ändamålet har projektdeltagarna undersökt ett urval konferenser och konferensartiklar via sina publiceringsdatabaser under ett specifikt tidsintervall och beskrivit dem utifrån ett gemensamt schema.Undersökningen har visat att publiceringsdatabaserna fyller en viktig funktion för att synliggöra konferenspublikationer. Vi har funnit att minst ca. 50 % av konferensartiklarna kan publiceras som post-prints i våra publiceringsdatabaser. Därför är det av stor vikt att fortsätta arbetet med att utnyttja de lokala publiceringsdatabaserna som publiceringskanal och att inte bara använda dem som ett verktyg för parallellpublicering och primärpublicerat material, som avhandlingar och rapporter, utan även som en källa framförallt för konferensartiklar ”utan hem”, som vi nu vet utgör en stor del av vårt undersökningsmaterial (ca. 15 %).Mellan 20-25 % av de undersökta artiklarna fanns i något slags öppet OA-arkiv; ca. hälften av dessa fanns i någon av projektdeltagarnas egen publiceringsdatabas. Detta talar för att den egna publiceringsdatabasen är en viktig faktor för öppen tillgänglighet.Ca. 10% av konferenserna i studien hade en uttrycklig OA-policy eller gav uttryck för en sådan genom att öppet tillgängliggöra konferensartiklar på sina konferenssajter. Ett stort problem när det gäller parallellpublicering av konferensartiklar är just bristen på information om OA-policy.Konferenspubliceringslandskapet är komplicerat och parallellpubliceringen av dokument härifrån är mycket tidskrävande. Vi skulle framför allt önska en liknande policy-resurs som SHERPA/RoMEO för konferenser. Men för närvarande finns inget annat alternativ än att lusläsa konferensernas upphovsrättsinformation till författarna och av denna försöka dra slutsatser om ev. parallellpublicering.För att underlätta framtida hantering och klassificering av konferensartiklar i svenska publicerings-databaser, framför allt med tanke på ev. framtida nationella bibliometriska analyser via SwePub, föreslås ett antal rekommendationer.
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| 2. |
- Gunnarsson, Tommy, 1978-
(författare)
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MICROWAVE IMAGING OF BIOLOGICAL TISSUES: applied toward breast tumor detection
- 2007
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Microwave imaging is an efficient diagnostic modality for non-invasively visualizing dielectric contrasts of non-metallic bodies. An increasing interest of this field has been observed during the last decades. Many application areas in biomedicine have been issued, recently the breast tumor detection application using microwave imaging.Many groups are working in the field at the moment for several reasons. Breast cancer is a major health problem globally for women, while it is the second most common cancer form for women causing 0.3 % of the yearly female death in Sweden. Medical imaging is considered as the most effective way of diagnostic breast tumors, where X-ray mammography is the dominating technique. However, this imaging modality still suffers from some limitations. Many women, mostly young ones, have radiographically dense breasts, which means that the breast tissues containing high rates of fibroglandular tissues. In this case the density is very similar to the breast tumor and the diagnosis is very difficult. In this case alternative modalities like Magnetic Resonance Imaging (MRI) with contrast enhancement and Ultrasound imaging are used, however those are not suitable for large scale screening program.Another limitation is the false-negative and false-positive rate using mammography, in general 5–15 % of the tumors are not detected and many cases have to go though a breast biopsy to verify a tumor diagnosis. At last the mammography using breast compression sometimes painful, and utilizing ionizing X-rays. The big potential in microwave imaging is the reported high contrast of complex permittivity between fibroglandular tissues and tumor tissues in breasts and that it is a non-ionizing method which probably will be rather inexpensive.The goal with this work is to develop a microwave imaging system able to reconstruct quantitative images of a female breast. In the frame of this goal this Licentiate thesis contains a brief review of the ongoing research in the field of microwave imaging of biological tissues, with the major focus on the breast tumor application. Both imaging algorithms and experimental setups are included. A feasibility study is performed to analyze what response levels could be expected, in signal properties, in a breast tumor detection application. Also, the usability of a 3D microwave propagation simulator, (QW3D), in the setup development is investigated. This is done by using a simple antenna setup with a breast phantom with different tumor positions. From those results it is clear that strong responses are obtained by a tumor presence and the diffracted responses gives strong information about inhomogeneities inside the breast. The second part of this Licentiate thesis is done in collaboration between Mälardalen University and Supélec. Using the existing planar 2.45 GHz microwave camera and the iterative non-linear Newton Kantorovich code, developed at Département de Recherches en Electromagnétisme (DRE) at Supélec, as a starting point, a new platform for both real-time qualitative imaging and quantitative images of inhomogeneous objects are investigated. The focusing is related to breast tumor detection. For the moment the tomographic performance of the planar camera is verified in simulations through a comparison with other setups. Good calibration is observed, but still experimental work concerning phantom development etc. is needed before experimental results on breast tumor detection may be obtained.
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| 3. |
- Henriksson, Tommy, 1978-
(författare)
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CONTRIBUTION TO QUANTITATIVE MICROWAVE IMAGING TECHNIQUES FOR BIOMEDICAL APPLICATIONS
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation presents a contribution to quantitative microwave imaging for breast tumor detection. The study made in the frame of a joint supervision Ph.D. thesis between University Paris-SUD 11 (France) and Mälardalen University (Sweden), has been conducted through two experimental microwave imaging setups, the existing 2.45 GHz planar camera (France) and the multi-frequency flexible robotic system, (Sweden), under development. In this context a 2D scalar flexible numerical tool based on a Newton-Kantorovich (NK) scheme, has been developed. Quantitative microwave imaging is a three dimensional vectorial nonlinear inverse scattering problem, where the complex permittivity of an object is reconstructed from the measured scattered field, produced by the object. The NK scheme is used in order to deal with the nonlinearity and the ill-posed nature of this problem. A TM polarization and a two dimensional medium configuration have been considered in order to avoid its vectorial aspect. The solution is found iteratively by minimizing the square norm of the error with respect to the scattered field data. Consequently, the convergence of such iterative process requires, at least two conditions. First, an efficient calibration of the experimental system has to be associated to the minimization of model errors. Second, the mean square difference of the scattered field introduced by the presence of the tumor has to be large enough, according to the sensitivity of the imaging system. The existing planar camera associated to a flexible 2D scalar NK code, are considered as an experimental platform for quantitative breast imaging. A preliminary numerical study shows that the multi-view planar system is quite efficient for realistic breast tumor phantoms, according to its characteristics (frequency, planar geometry and water as a coupling medium), as long as realistic noisy data are considered. Furthermore, a multi-incidence planar system, more appropriate in term of antenna-array arrangement, is proposed and its concept is numerically validated. On the other hand, an experimental work which includes a new fluid-mixture for the realization of a narrow band cylindrical breast phantom, a deep investigation in the calibration process and model error minimization, is presented. This conducts to the first quantitative reconstruction of a realistic breast phantom by using multi-view data from the planar camera. Next, both the qualitative and quantitative reconstruction of 3D inclusions into the cylindrical breast phantom, by using data from all the retina, are shown and discussed. Finally, the extended work towards the flexible robotic system is presented.
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| 4. |
- Linde, Peter, et al.
(författare)
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Accessibility and self-archiving of conference articles : A study on a selection of Swedish institutional repositories
- 2011
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Ingår i: Information Services and Use. - Guimarães : IOS Press. - 0167-5265 .- 1875-8789. ; 31:3-4, s. 259-269, s. 123-
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Tidskriftsartikel (refereegranskat)abstract
- The main purpose of this project has been to examine the accessibility of refereed conference articles and the OA- and publishing policies of conferences in order to in this way elucidate different aspects concerning self-archiving in Swedish institutional repositories. For this purpose, the project participants have examined a number of conferences and references to conference articles via their institutional repositories during a specific time period and described these from the perspective of a common scheme. The study has showed that the local institutional repositories fill an important role to make conference publications visible. We have found that ca. 50% of the conference papers can be published as postprints in our institutional repositories. We have noticed that ca. 15% or the studied conference articles are not available at all. It is, therefore, of great importance to use local institutional repositories as a publishing channel, not only for primary published material such as dissertations and reports, but also as a source for finding these conference articles "without a home". Between 20-25% of the examined articles were found in some type of OA archive; ca. half of these were found in one of the project participants' own institutional repositories. This indicates that the publishing database of respective higher education institution is an important factor for open accessibility. Ca. 10% of the conferences in the study had an explicit OA policy or expressed such a policy by openly making conference articles accessible on their conference sites. A big problem when it comes to self-archiving of conference articles is the lack of information about OA policy. The landscape of conference publishing is complex and the self-archiving of documents from conferences is very time-consuming. Above all, we would wish a policy resource for conferences similar to the SHERPA/RoMEO. At present, however, there is no other alternative than scrutinizing the conferences' copyright information to the authors and from this attempt to draw conclusions about possible self-archiving. To facilitate the future handling and classification of conference articles in Swedish institutional repositories a number of recommendations are suggested.
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