| 11. |
|
|
| 12. |
|
|
| 13. |
|
|
| 14. |
- Vidmar, T., et al.
(författare)
-
Equivalence of computer codes for calculation of coincidence summing correction factors - Part II
- 2016
-
Ingår i: Applied Radiation and Isotopes. - : Elsevier BV. - 0969-8043 .- 1872-9800. ; 109, s. 482-486
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to check for equivalence of computer codes that are capable of performing calculations of true coincidence summing (TCS) correction factors. All calculations were performed for a set of well-defined detector parameters, sample parameters and decay scheme data. The studied geometry was a point source of Ba-133 positioned directly on the detector window of a low-energy (n-type) detector. Good agreement was established between the TCS correction factors computed by the different codes.
|
|
| 15. |
- Diedrichs, Ben, et al.
(författare)
-
Crosswind stability of high-speed train on a high embankment
- 2007
-
Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit. - 0954-4097 .- 2041-3017. ; 221:2, s. 205-225
-
Tidskriftsartikel (refereegranskat)abstract
- This work presents aerodynamic results of crosswind stability obtained numerically and experimentally for the leading control unit (class 808) of Deutsche Bahn AG's high-speed train Inter-CityExpress 2. The train model is on top of a 6 m high embankment in accordance with the proposed European code for interoperable trains, the so-called technical specifications for interoperability. The purpose of the study is to convey the predictive accuracy that typical steady-state computational fluid dynamics-Reynolds average Navier-Stokes methods (industry standard) return and to contribute to the understanding of the aerodynamics for the current application. Attention is drawn to the aerodynamics around the train and embankment when subjected to a steady block profile crosswind of 30 degrees yaw angle on the basis of the onset velocity far upstream the embankment. The Re (Reynolds number) of the embankment cases is 4.6 x 10(6). Calculated results are obtained with the commercial code STAR-CD, with exclusively hexahedral meshes with a total cell count of 13.5 x 10(6). Results are obtained when the train stands on the windward and leeward tracks on top of the embankment. These results are first compared with a flat ground case from a previous study. Then experimental data are obtained in a high-pressure wind tunnel with a model scale of 1:100. Re effects are compensated by raising the ambient pressure by a factor of 60, which increases the air density and thus the Re by a similar factor. Calculated results are in fair agreement with the experiments, where both the calculations and the experiments predict the leeward case to be the more critical one. In addition, the related consequences on the mechanical behaviour, i.e. the stability of the car, are briefly addressed by means of a quasi-static mechanical analysis. The results of the present study indicate that the 6 m high embankment concerning the current train reduces the permissible crosswind speed with approximately 20 per cent.
|
|
| 16. |
|
|
| 17. |
|
|
| 18. |
- Ghandi, Reza, et al.
(författare)
-
Surface-passivation effects on the performance of 4H-SiC BJTs
- 2011
-
Ingår i: IEEE Transactions on Electron Devices. - 0018-9383 .- 1557-9646. ; 58, s. 259-265
-
Tidskriftsartikel (refereegranskat)abstract
- In this brief, the electrical performance in terms of maximum current gain and breakdown voltage is compared experimentally and by device simulation for 4H-SiC BJTs passivated with different surface-passivation layers. Variation in bipolar junction transistor (BJT) performance has been correlated to densities of interface traps and fixed oxide charge, as evaluated through MOS capacitors. Six different methods were used to fabricate SiO2 surface passivation on BJT samples from the same wafer. The highest current gain was obtained for plasma-deposited SiO2 which was annealed in N2O ambient at 1100 °C for 3 h. Variations in breakdown voltage for different surface passivations were also found, and this was attributed to differences in fixed oxide charge that can affect the optimum dose of the high-voltage junction-termination extension (JTE). The dependence of breakdown voltage on the dose was also evaluated through nonimplanted BJTs with etched JTE.
|
|
| 19. |
- Granéli, C., et al.
(författare)
-
Urinary tract anomalies and urinary tract dysfunction in children with Hirschsprung disease—Is follow-up indicated?
- 2019
-
Ingår i: Journal of Pediatric Surgery. - : Elsevier BV. - 0022-3468. ; 54:10, s. 2012-2016
-
Tidskriftsartikel (refereegranskat)abstract
- Background/Purpose: Urinary tract function in children with Hirschsprung disease (HD) is rarely considered. Aim: to evaluate the prevalence of urinary tract anomalies and dysfunction in children with HD compared to controls. Methods: This was an observational cross sectional case–control study. Children with HD who underwent transanal endorectal pull-through technique (TERPT) from 2005 to 2017 were invited to participate. Ultrasound of the urinary tract was performed postoperatively. Children > 4 years were asked to answer a urinary tract function questionnaire. Controls were age-matched healthy children. Ethical approval was obtained. Results: Seventy two children with HD and TERPT were included. Ultrasound was performed in 58 children (83%) post-TERPT. Ten anomalies were diagnosed in six children (10%). Structural anomalies included abnormal kidney size (7%), renal agenesis (2%), prominent calyces (2%) and renal pelvis anomaly (25). Probable acquired anomalies included hydronephrosis (2%), hydroureter (2%) and parenchymal damage (2%). One child had a prior nephrectomy owing to a Wilms’ tumor. All 37 children > 4 years (27 boys and 10 girls), median aged 8 years (range 4–12), answered the questionnaire as did 284 healthy controls (144 boys and 140 girls). Boys with HD reported a higher frequency of enuresis: 65% versus 9% (p = 0.001) and urinary tract infections: 18% versus 3% (p = 0.012). Girls with HD reported enuresis more frequently (60%) than healthy girls (7%) (p = 0.001). Children with HD with constipation reported enuresis more frequently (p = 0.038). Conclusions: Urinary tract anomalies and dysfunction deserve attention in the follow-up of children with HD. We suggest screening for urinary tract anomalies and urinary tract symptoms in follow-up of children with HD. Type of study: Treatment study. Level: III.
|
|
| 20. |
|
|
