| 1. |
- He, Guojing, 1964-, et al.
(författare)
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Assessment of a railway concrete arch bridge by numerical modelling and measurements
- 2008
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Ingår i: <em>Bridge Maintenance, Safety, Management, Health Monitoring and Informatics</em>. - Leiden : CRC Press. ; , s. 3733-3742
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Konferensbidrag (refereegranskat)abstract
- Two main railway concrete arch bridges have been investigated in northern Sweden: the Vindel Bridge over the Vindel River with a span of 110 m and the Långforsen Bridge over the Kalix River with a span of 90 m. The bridges were constructed in the 1950s with similar designs. In order to investigate the possibility to increase the axle load from 225 kN to 250kN, two 3-D Finite Element models with shell elements were developed and two field tests were carried out with passing trains and ambient vibrations. The measurement frequencies and mode shapes were studied with the stochastic subspace identification method in the time domain. Based on a comparison of the predictions of the FE analyses and the results of the field tests, the FE models were updated. It was found that it was possible to make good predictions of the actual dynamic response with reasonable assumptions of material properties and joint stiffness in the structure.
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| 2. |
- Bennitz, Anders, et al.
(författare)
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Dynamic behaviour of the Vindel River railway bridge
- 2006
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Ingår i: Condition Monitoring and Diagnostic Engineering Management. - Luleå : Luleå tekniska universitet. - 9789163188060 ; , s. 721-729
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Konferensbidrag (refereegranskat)abstract
- The Swedish Railway administration has launched several projects aimed at increasing the accessibility of the railway lines in northern Sweden to meet future demands. One of these lines connects the southern and northern parts of Sweden and constitutes one of the major arteries for the transportation of heavy goods. Major investment are planned to upgrade the load bearing capacity of this railway line. The work is mainly focused on the larger structures and their dynamical properties. These properties can be used to assess existing infrastructure and to evaluate the performance. Advantages are obvious since the existing structural integrity form the base for investments in structural repair and upgrade of bridges. The Vindel River Railway Bridge situated 55 kilometers northwest of Umeå came into focus when large motion was discovered during train passages. The behaviour of the bridge crossing the river of Vindeln has been measured two times. Measurements of displacements and acceleration of the bridge during train passages has been conducted, the first measurements was done to give more experience on the motion of the bridge and to try out new sensors. The second measurement gave more information about the bridge's motion, results that could be used to calibrate a 3D FE-Model of the bridge used in the study. Based on the measurements, eigenfrequencies in the range of 0 to 8 Hz could be detected, modal shapes up to the ninth order could be extracted, deflections and transverse displacements for different sets of train and different train speeds were also found. However, new measurements are planned for this summer and will hopefully reinforce the already attained result and give answers to some of the unresolved questions.
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| 3. |
- Borggren, Marie, et al.
(författare)
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Neutralizing Antibody Response and Antibody-Dependent Cellular Cytotoxicity in HIV-1-Infected Individuals from Guinea-Bissau and Denmark
- 2016
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Ingår i: AIDS Research and Human Retroviruses. - : Mary Ann Liebert Inc. - 0889-2229 .- 1931-8405. ; 32:5, s. 434-442
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Tidskriftsartikel (refereegranskat)abstract
- The development of therapeutic and prophylactic HIV vaccines for African countries is urgently needed, but the question of what immunogens to use needs to be answered. One approach is to include HIV envelope immunogens derived from HIV-positive individuals from a geographically concentrated epidemic with more limited viral genetic diversity for a region-based vaccine. To address if there is a basis for a regional selected antibody vaccine, we have screened two regionally separate cohorts from Guinea-Bissau and Denmark for neutralizing antibody activity and antibody-dependent cellular cytotoxicity (ADCC) against local and nonlocal circulating HIV-1 strains. The neutralizing activity did not demonstrate higher potential against local circulating strains according to geography and subtype determination, but the plasma from Danish individuals demonstrated significantly higher inhibitory activity than that from Guinea-Bissau individuals against both local and nonlocal virus strains. Interestingly, an opposite pattern was observed with ADCC activity, where Guinea-Bissau individual plasma demonstrated higher activity than Danish plasma and was specifically against the local circulating subtype. Thus, on basis of samples from these two cohorts, no local-specific neutralizing activity was detected, but a local ADCC response was identified in the Guinea-Bissau samples, suggesting potential use of regional immunogens for an ADCC-inducing vaccine.
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| 4. |
- Enochsson, Ola, et al.
(författare)
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Assessment and condition monitoring of a concrete railway bridge in Kiruna, Sweden
- 2006
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Ingår i: Bridge maintenance, safety, management, life-cycle performance and cost. - London : Taylor and Francis Group. - 0415403154
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Konferensbidrag (refereegranskat)abstract
- A two-span railway concrete trough bridge over Luossajokk in Kiruna in northern Sweden has been studied. The owner wanted to increase the axle loads from 250 to 300 kN in order to reduce freight costs for iron ore. Examples are given of methods used and results obtained from the assessment where bending, shear and fatigue were studied. Material properties, loads and load carrying capacity were evaluated using deterministic and probabilistic methods. It was shown that the bridge could carry the higher loads with a safety index β > 4.7 for reasonable assumptions of the load distributions. A measurement system was installed to check the actual level of critical strains and the worst positions of the train. Results are also given from a condition monitoring program 2001-2006, launched to periodically check the development of strains with time.
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| 5. |
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| 6. |
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| 7. |
- Enochsson, Ola, et al.
(författare)
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Dynamic amplification factors for a riveted steel bridge : assessment by monitoring of the Keräsjokk bridge in northern Sweden
- 2007
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Ingår i: Sustainable bridges. - Wrocław : Dolnoslaskie Wydawnictwo Edukacyjne. - 9788371251610 ; , s. 435-444
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Konferensbidrag (refereegranskat)abstract
- Measurements were carried out in order to improve an assessment of a riveted steel bridge from 1911. Dynamic Amplification factors, DAF, were estimated for different parts of the bridge by measurements of deflections and strains for a train passing over the bridge with different speeds. The measured dynamic amplification factors were considerably lower than the corresponding ones calculated according to available codes. Due to this it was possible to increase the axle load on the bridge from 22.5 to 25 tons.
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| 8. |
- He, Guojing, et al.
(författare)
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Numerical modeling and dynamic behavior of a railway concrete bridge over the Vindel River in Sweden
- 2006
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Ingår i: Bridge maintenance, safety, management, life-cycle performance and cost. - London : Taylor & Francis Group. - 0415403154 ; , s. 104-111
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Konferensbidrag (refereegranskat)abstract
- The Vindel Railway Bridge in northern Sweden is composed of a concrete deck, columns and an arch with a span of 110 m and a height of 22 m. In order to check the possibility to increase the axle load from 225 kN to 250 kN, the properties of the bridge needed to be evaluated. Especially, the dynamic behavior of the bridge is an important factor as it is affecting the load bearing capacity and the serviceability. In this paper, two types of three-dimensional (3-D) finite element models have been developed. One uses shell elements and the other uses beam elements. Based on the 3-D FE models, the effects of nonstructural mass, side spans and connection between columns and deck on the dynamic behavior are discussed. Furthermore, field test data from passing through train are compared with the results calculated by the models. The numerical simulations of the dynamic response coincide reasonably well with the field test data.
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| 9. |
- Iversen, Tor, et al.
(författare)
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Coordination of care in the Nordic countries
- 2016
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Ingår i: Nordic Journal of Health Economics. - : University of Oslo Library. - 1892-9729 .- 1892-9710. ; 4:1, s. 41-55
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Tidskriftsartikel (refereegranskat)abstract
- Coordination of health care exists at many different levels and in many different forms. We describe the similarities and differences in coordination mechanisms among the Nordic countries. In some respects, the Nordic countries approach coordination problems in similar ways although differences exist. The overall pattern shows that Finland and Sweden have less country-wide coordination compared with the other countries. There are many questions and few answers with regard to which mechanisms work best. Hence, coordination mechanisms in health care seem to be an important area for further research. We outline a few topics for future joint Nordic research in this area.
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| 10. |
- Nilsson, Martin P., et al.
(författare)
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Nordic anal cancer (NOAC) group consensus guidelines for risk-adapted delineation of the elective clinical target volume in anal cancer
- 2023
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Ingår i: Acta Oncologica. - : Taylor & Francis. - 0284-186X .- 1651-226X. ; 62:8, s. 897-906
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Tidskriftsartikel (refereegranskat)abstract
- Background: To date, anal cancer patients are treated with radiotherapy to similar volumes despite a marked difference in risk profile based on tumor location and stage. A more individualized approach to delineation of the elective clinical target volume (CTVe) could potentially provide better oncological outcomes as well as improved quality of life. The aim of the present work was to establish Nordic Anal Cancer (NOAC) group guidelines for delineation of the CTVe in anal cancer.Methods: First, 12 radiation oncologists reviewed the literature in one of the following four areas: (1) previous delineation guidelines; (2) patterns of recurrence; (3) anatomical studies; (4) common iliac and para-aortic recurrences and delineation guidelines. Second, areas of controversy were identified and discussed with the aim of reaching consensus.Results: We present consensus-based recommendations for CTVe delineation in anal cancer regarding (a) which regions to include, and (b) how the regions should be delineated. Some of our recommendations deviate from current international guidelines. For instance, the posterolateral part of the inguinal region is excluded, decreasing the volume of irradiated normal tissue. For the external iliac region and the cranial border of the CTVe, we agreed on specifying two different recommendations, both considered acceptable. One of these recommendations is novel and risk-adapted; the external iliac region is omitted for low-risk patients, and several different cranial borders are used depending on the individual level of risk.Conclusion: We present NOAC consensus guidelines for delineation of the CTVe in anal cancer, including a risk-adapted strategy.
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