scholarly journals 3D simulation studies of tokamak plasmas using MHD and extended-MHD models

1997 ◽  
Author(s):  
W. Park ◽  
Z. Chang ◽  
E. Fredrickson ◽  
G.Y. Fu ◽  
N. Pomphrey ◽  
...  
Keyword(s):  
3D Simulation ◽  
Tokamak Plasmas ◽  
Simulation Studies ◽  
Extended Mhd

Magnetic resonance imaging and 3D simulation studies of biofilm accumulation and cleaning on reverse osmosis membranes

2010 ◽  
Vol 88 (4) ◽  
pp. 401-408 ◽  
Author(s):  
S.A. Creber ◽  
T.R.R. Pintelon ◽  
D.A.W. Graf von der Schulenburg ◽  
J.S. Vrouwenvelder ◽  
M.C.M. van Loosdrecht ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Reverse Osmosis ◽  
3D Simulation ◽  
Simulation Studies ◽  
Resonance Imaging ◽  
Reverse Osmosis Membranes

scholarly journals Analysis of ELM stability with extended MHD models in JET, JT-60U and future JT-60SA tokamak plasmas

2017 ◽  
Vol 60 (1) ◽  
pp. 014032 ◽  
Author(s):  
N Aiba ◽  
S Pamela ◽  
M Honda ◽  
H Urano ◽  
C Giroud ◽  
...  
Keyword(s):  
Tokamak Plasmas ◽  
Extended Mhd

Benefits from Computerized Adaptive Testing as Seen in Simulation Studies

1999 ◽  
Vol 15 (2) ◽  
pp. 91-98 ◽  
Author(s):  
Lutz F. Hornke
Keyword(s):  
Measurement Error ◽  
Computerized Adaptive Testing ◽  
Test Procedure ◽  
Adaptive Testing ◽  
Parameter Estimates ◽  
Simulation Studies ◽  
Computerized Adaptive Test ◽  
Item Banks ◽  
Item Parameters ◽  
General Reliability

Summary: Item parameters for several hundreds of items were estimated based on empirical data from several thousands of subjects. The logistic one-parameter (1PL) and two-parameter (2PL) model estimates were evaluated. However, model fit showed that only a subset of items complied sufficiently, so that the remaining ones were assembled in well-fitting item banks. In several simulation studies 5000 simulated responses were generated in accordance with a computerized adaptive test procedure along with person parameters. A general reliability of .80 or a standard error of measurement of .44 was used as a stopping rule to end CAT testing. We also recorded how often each item was used by all simulees. Person-parameter estimates based on CAT correlated higher than .90 with true values simulated. For all 1PL fitting item banks most simulees used more than 20 items but less than 30 items to reach the pre-set level of measurement error. However, testing based on item banks that complied to the 2PL revealed that, on average, only 10 items were sufficient to end testing at the same measurement error level. Both clearly demonstrate the precision and economy of computerized adaptive testing. Empirical evaluations from everyday uses will show whether these trends will hold up in practice. If so, CAT will become possible and reasonable with some 150 well-calibrated 2PL items.

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