| 1. |
- Al-Rawi, Mohammed, et al.
(författare)
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Algorithms for the Detection of First Bottom Returns and Objects in the Water Column in Side-Scan Sonar Images
- 2017
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Ingår i: OCEANS '17 A Vision for our Marine Future OCEANS '17. - Aberdeen, United Kingdom. - 9781509052783
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Konferensbidrag (refereegranskat)abstract
- Underwater imaging has become an active research area in recent years as an effect of increased interest in underwater environments and is getting potential impact on the world economy, in what is called blue growth. Since sound propagates larger distances than electromagnetic waves underwater, sonar is typically used for underwater imaging. One interesting sonar image setting is comprised of using two parts (left and right) and is usually referred to as sidescan sonar. The image resulted from sidescan sonars, which is called waterfall image, usually has to distinctive parts, the water column and the image seabed. Therefore, the edge separating these two parts, which is called the first bottom return, is the real distance between the sonar and the seabed bottom (which is equivalent to sensor primary altitude). The sensory primary altitude can be measured if the imaging sonar is complemented by interferometric sonar, however, simple sonar systems have no way to measure the first bottom returns other than signal processing techniques. In this work, we propose two methods to detect the first bottom returns; the first is based on smoothing cubic spline regression and the second is based on a moving average filter to detect signal variations. The results of both methods are compared to the sensor primary altitude and have been successful in 22 images out of 25.
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| 2. |
- Al-Rawi, M. S., et al.
(författare)
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Intensity normalization of sidescan sonar imagery
- 2016
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Ingår i: 2016 6th International Conference on Image Processing Theory, Tools and Applications, IPTA 2016. - 9781467389105
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Konferensbidrag (refereegranskat)abstract
- Sonar imaging is currently the exemplary choice used in underwater imaging. However, since sound signals are absorbed by water, an image acquired by a sonar will have gradient illumination; thus, underwater maps will be difficult to process. In this work, we investigated this phenomenon with the objective to propose methods to normalize the images with regard to illumination. We propose to use MIxed exponential Regression Analysis (MIRA) estimated from each image that requires normalization. Two sidescan sonars have been used to capture the seabed in Lake Vattern in Sweden in two opposite directions west-east and east-west; hence, the task is extremely difficult due to differences in the acoustic shadows. Using the structural similarity index, we performed similarity analyses between corresponding regions extracted from the sonar images. Results showed that MIRA has superior normalization performance. This work has been carried out as part of the SWARMs project (http://www.swarms.eu/).
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| 3. |
- Hansson, Therese, et al.
(författare)
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Enhetliga analyser av narkotika i urin krävs för rättssäkerheten.
- 2015
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Ingår i: Läkartidningen. - 0023-7205. ; 112
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Tidskriftsartikel (refereegranskat)abstract
- Drugs of abuse testing is used in various areas of society for detection and follow-up of drug use. In routine laboratory drug testing, immunoassays are employed for initial screening of specimens to indicate the presence of drugs. To confirm a positive screening test, a secondary analysis by mass spectrometry is performed. The »cut-off« is the pre-defined concentration threshold of a drug or drug metabolite above which the sample is considered positive. A reading below this level implies a negative test result. Swedish drug testing laboratories currently employ varying cut-offs to distinguish between a positive and a negative test result. Because a positive drug test may have serious legal consequences to the individual, it is of importance that testing is performed and judged equally, regardless of where it is performed. A national harmonization of cut-offs is therefore warranted. Based on data from four major Swedish drug testing laboratories, and considering the recommendations in international guidelines, a proposal for national harmonization of urine cut-offs for the most common set of drugs of abuse is presented.
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| 4. |
- Oldsjö, Fredrik, et al.
(författare)
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Hur kan vi förbättra bedömningen av pedagogisk skicklighet? : Erfarenheter från den nationella sakkunnigkursen
- 2018
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Ingår i: nu2018 - Det akademiska lärarskapet.
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Konferensbidrag (refereegranskat)abstract
- Pedagogisk skicklighet anses av många vara svårbedömd men under det senaste dryga decenniet har en mer reflekterad praktik kring dessa bedömningar börjat utvecklas. En åtgärd för att stödja en sådan utveckling har varit satsningen på en nationell sakkunnigkurs, där universitetslärare från många olika lärosäten har mötts för att utveckla sin kompetens i och utbyta erfarenheter om kollegial bedömning av pedagogisk skicklighet.Genom ett samarbete mellan flera lärosäten i Sverige har sedan 2010 en nationell kurs för pedagogiskt sakkunniga anordnats vid sex tillfällen (http://www.swednetwork.se/ny-kurs-forpedagogiskt-sakkunniga-under-vt-17/). Det övergripande syftet med kursen är att stärka bedömningen av pedagogisk skicklighet genom att främja professionella bedömningsprocesser och sakkunnigutlåtanden av hög kvalitet.Kursen riktar sig till personer i akademien som vill utveckla sin förmåga att bedöma pedagogisk skicklighet vid tjänstetillsättning, ansökan om befordran, ansökan om docentur eller ansökan till en pedagogisk karriärväg. Hittills har 125 deltagare från 24 lärosäten i Sverige genomgått kursen. Bland deltagarna märks lärare som anlitas som pedagogiskt sakkunniga, ordförande och ledamöter i lärarförslagsnämnder, samt högskolepedagogiskt ansvariga som utvecklar eller samordnar lokala pedagogiska meriteringsvägar.Kursen omfattar två veckors arbete och syftar till att utveckla deltagarnas förmåga att bedöma pedagogisk skicklighet genom granskning av underlag i form av pedagogiska portföljer eller motsvarande. Varje deltagare får under kursens gång granska fem olika ansökningar och ska skriva två sakkunnigutlåtanden över tidigare ej bedömda underlag som sedan delges portföljförfattarna. Deltagarna delas in i grupper som leds av en mentor och får i grupperna löpande diskutera de frågor som uppstår i arbetet med olika portföljer och olika lärosätesspecifika kriterier för pedagogisk skicklighet. Vilka brister finns i den aktuella dokumentationen av pedagogisk skicklighet och hur kan sakkunnigutlåtandet stimulera till vidare utveckling av den pedagogiska meritportföljen och till ökad förståelse generellt av hur en fungerande och autentisk dokumentation bör se ut? Hur bör ett sakligt och tydligt utlåtande utformas för att på bästa sätt ge återkoppling till uppdragsgivare och sökande lärare?Kursledare och mentorer för respektive deltagargrupper är personer med gedigen erfarenhet av att som sakkunnig bedöma pedagogisk skicklighet. Kursledarna är verksamma vid olika lärosäten och representerar för närvarande Lunds universitet, Mälardalens högskola, Stockholms universitet, Umeå universitet och Uppsala universitet. Kursledarna har drivit kursen med stöd av sina respektive lärosäten och av det nationella högskolepedagogiska nätverket Swednet.Presentationen kommer att beröra följande frågeställningar:Vad är för- och nackdelarna med att kursen bidrar till utvecklingen av en nationell samsyn i bedömningen av pedagogisk skicklighet?Hur påverkas bedömningen av ämnesdidaktik och forskningsanknytning av att kursens deltagare är från olika discipliner?Vad innebär det att diskutera bedömning av pedagogisk skicklighet för sig, utan att samtidigt diskutera bedömning av vetenskaplig skicklighet?Frågorna diskuteras utifrån utvärderingar av genomförda kurser som illustrerar deltagarnas åsikter om kursen och hur de i efterhand ser på värdet av kursen.ReferenserMeizlish, Deborah & Kaplan, Matthew (2008). “Valuing and Evaluating Teaching in Academic Hiring: A Multidisciplinary, Cross-Institutional Study”. I The Journal of Higher Education, Vol. 79, No. 5, pp. 489-512.Olsson, Thomas & Roxå, Torgny (2013). “Assessing and rewarding excellent academic teachers for the benefit of an organization”. I European Journal of Higher Education , 3:1, pp. 40-61.Ryegård, Åsa & Apelgren, Karin & Olsson, Thomas (Red.) Att belägga, bedöma och belöna pedagogisk skicklighet. Uppsala: 2010. https://gupea.ub.gu.se/bitstream/2077/22232/1/gupea_2077_22232_1.pdfTrevitt, Chris & Stocks, Claire (2012). “Signifying authenticity in academic practice a framework for better understanding and harnessing portfolio assessment”. I Evaluation in Higher Education, 37:2, pp. 245-257.
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| 5. |
- Olsson, Thomas, et al.
(författare)
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How can we improve assessment of pedagogical competence? : Experiences from a national Swedish course.
- 2018
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Ingår i: ISSOTL18 - Toward a Learning Culture. ; , s. 121-122
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Konferensbidrag (refereegranskat)abstract
- Assessment of pedagogical competence is often considered difficult and challenging, but during the last 10‐15 years a more reflected and scholarly practice has developed (Ryegård et al., 2010; Olsson & Roxå, 2013). In Sweden, this development has been supported on a national level by offering a course for prospective assessors organized through a cooperation between several universities. The course has been given on six occasions since 2010 and academics from different disciplines, faculties and universities meet (on campus and online) to develop their assessment skills and exchange experiences about peer‐review based assessment of pedagogical competence. The overall aim of the course is to strengthen the assessment of pedagogical competence by promoting professional assessment processes and expert assessments of high quality. The course is aimed for academics who want to develop their ability to assess pedagogical competence as part of assessments of applications for appointment, promotion or teaching awards. Among the participants we find teachers who act as pedagogical experts, chairpersons and members of teacher appointment committees, as well as university teachers who develop or coordinate local pedagogical reward systems. So far, 125 participants from 24 universities have completed the course.The presentation will address the following issues: The course could contribute to the development of a national consensus in the assessment of pedagogical competence. Which are the advantages and disadvantages of this development? How is the assessment of teaching and learning in the disciplines (subject didactics) and connections to research affected by the fact that the participants in the course are from different disciplines? What does it mean to discuss assessment of pedagogical competence without discussing assessment of scientific competence at the same time? Which are the shortcomings in the documentation and how can the expert assessment and feedback stimulate further development of the portfolio and an increased understanding of how an authentic documentation could be presented? How should a clear assessment of high quality be formulated to give feedback to universities as well as applicants (Meizlish & Kaplan, 2008; Trevitt & Stocks, 2012)? These questions are discussed based on evaluations of completed courses that illustrate participants’ views on the course and how they afterwards reflect on the value of the course.Course leaders and mentors are academics with extensive experience in assessing pedagogical competence. The course leaders have given the course with the support of their respective universities and the national educational network Swednet (a member of ICED).
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| 6. |
- Sakthivel, Priya, et al.
(författare)
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Circulating soluble CTLA-4 is related to inflammatory markers in the 70 year old population
- 2010
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Ingår i: Scandinavian Journal of Clinical and Laboratory Investigation. - : Informa UK Limited. - 0036-5513 .- 1502-7686. ; 70:4, s. 237-243
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Measurement of inflammatory mediators is an important tool to assess inflammation. We have, therefore, conducted a survey within the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study to evaluate the inter-relationship between soluble CTLA-4 (sCTLA-4) and other inflammatory markers. MATERIALS AND METHODS: This is a population-based study, designed to quantify the circulating serum levels of sCTLA-4 and other inflammatory markers such as CRP and pro-inflammatory cytokines and chemokines by in-house ELISA, Immuno-turbidimetry and multiplex ELISA, respectively. A total of 1016 Swedish Caucasians aged 70 years old were recruited. The statistical analysis was performed by ANOVA. RESULTS: The levels of sCTLA-4 were directly related to the levels of pro-inflammatory cytokines such as IL-6, IL-1alpha, IL-1beta, TNF-alpha, IFN-gamma and chemokines such as IL-8. However, the levels of sCTLA-4 were inversely related to the levels of MCP-1. Also, we could not demonstrate any relation between the levels of sCTLA-4 and CRP or soluble adhesion molecules. CONCLUSIONS: Circulating sCTLA-4 could be used as a biomarker for inflammation, potentially reflecting dysregulated T lymphocytes.
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| 7. |
- Österblom, Henrik, et al.
(författare)
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Human-induced trophic cascades and ecological regime shifts in the Baltic Sea
- 2007
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Ingår i: Ecosystems (New York. Print). - : Springer Science and Business Media LLC. - 1432-9840 .- 1435-0629. ; 10:6, s. 877-889
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Tidskriftsartikel (refereegranskat)abstract
- The ecosystems of coastal and enclosed seas are under increasing anthropogenic pressure worldwide, with Chesapeake Bay, the Gulf of Mexico and the Black and Baltic Seas as well known examples. We use an ecosystem model (Ecopath with Ecosim, EwE) to show that reduced top-down control (seal predation) and increased bottom-up forcing (eutrophication) can largely explain the historical dynamics of the main fish stocks (cod, herring and sprat) in the Baltic Sea between 1900 and 1980. Based on these results and the historical fish stock development we identify two major ecological transitions. A shift from seal to cod domination was caused by a virtual elimination of marine mammals followed by a shift from an oligotrophic to a eutrophic state. A third shift from cod to clupeid domination in the late 1980s has previously been explained by overfishing of cod and climatic changes. We propose that the shift from an oligotrophic to a eutrophic state represents a true regime shift with a stabilizing mechanism for a hysteresis phenomenon. There are also mechanisms that could stabilize the shift from a cod to clupeid dominated ecosystem, but there are no indications that the ecosystem has been pushed that far yet. We argue that the shifts in the Baltic Sea are a consequence of human impacts, although variations in climate may have influenced their timing, magnitude and persistence.
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