Filters
Results 1 - 10 of 16703
Results 1 - 10 of 16703.
Search took: 0.043 seconds
Sort by: date | relevance |
Anderson, David E.; Wezensky, Mark W.
Oak Ridge National Laboratory, Spallation Neutron Source (United States). Funding organisation: SC USDOE - Office of Science (United States)2012
Oak Ridge National Laboratory, Spallation Neutron Source (United States). Funding organisation: SC USDOE - Office of Science (United States)2012
AbstractAbstract
[en] The Spallation Neutron Source (SNS) has been in operation since 2006 and routinely operates at 1 MW of beam power. At 1 MW, the High Voltage Converter Modulators (HVCMs) are delivering 8-11 MW pulsed power to the Klystrons for up to 1185 us at 60 Hz. The pulsed output of the modulator has a substantial voltage droop operating in open-loop mode. Achieving 1.4 MW operations require an increase in the output pulse width of the HVCM, resulting in loss of LLRF control margin due to modulator voltage reduction at the end of the pulse. Initially, the HVCM was designed with a pulse width modulation scheme for droop compensation but early operations at full duty revealed this technique unreliable. Increasing the output voltage of the modulator would likely compromise system reliability. This paper proposes the use of alternate modulation schemes to address the voltage droop. The effect of frequency modulation and phase modulation on voltage droop is studied. Experimental results will also be presented.
Primary Subject
Source
1 Jan 2012; vp; 2012 International Paricle Accelerator Conference; New Orleans, LA (United States); 20-25 May 2012; KC0402010; ERKCSNR; AC05-00OR22725; Available from Oak Ridge National Laboratory (ORNL); Spallation Neutron Source
Record Type
Miscellaneous
Literature Type
Conference
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Wang, Y.; Ball, M.; Brabson, B.; Budnick, J.; Caussyn, D.D.; Chao, A.W.; Collins, J.; Derenchuk, V.; Dutt, S.; East, G.; Ellison, M.; Friesel, D.; Hamilton, B.; Huang, H.; Jones, W.P.; Lee, S.Y.; Li, D.; Liu, J.Y.; Minty, M.G.; Ng, K.Y.; Pei, X.; Riabko, A.; Sloan, T.; Syphers, M.; Yan, Y.T.; Zhang, P.L.1994
AbstractAbstract
[en] The response of particles trapped in one-dimensional resonance islands to betatron tune modulation resembles, yet is not equivalent to, that of a parametric resonant system. Experimental data obtained at Indiana University Cyclotron Facility for the fourth-order resonance islands have confirmed this characteristic feature. The beam, driven by betatron tune modulation, was observed to travel from near the center of resonance islands toward the separatrix. The experimental data are characterized by the onset of a large response at a critical modulation amplitude and frequency, which are compared with theoretical models. Possible future experiments are suggested
Primary Subject
Record Type
Journal Article
Journal
Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; ISSN 1063-651X;
; CODEN PLEEE8; v. 49(6); p. 5697-5705

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
No abstract available
Primary Subject
Record Type
Journal Article
Journal
Applied Optics; v. 13(8); p. 1755-1757
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
No abstract available
Original Title
Gestion de la configuracion en sistemas AM-FM
Primary Subject
Source
Empresarios Agrupados, A.I.E., Madrid (Spain); 534 p; ISBN 84-604-8403-3;
; Dec 1993; p. 99-111; 3. Meeting of Intergraph Users - Mapping and Utilities Group; Barcelona (Spain); 13 May 1992

Record Type
Report
Literature Type
Conference
Report Number
Country of publication
Reference NumberReference Number
Related RecordRelated Record
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] The modulation transfer function of a microdensitometer was measured by scanning a transmission sinusoidal test pattern by means of the microdensitometer and modulations at the various discrete spatial frequencies were measured from the profile of the image. The modulation versus spatial frequency data were fitted to a sin function and the MTF of the microdensitometer was estimated from the fitted curve. The MTF of the microdensitometer was sin (aφμ)/(aφμ) where a=0.0155 mm and μ is the spatial frequency in cycles/mm. Correction factor for the MTF of screen-film system at 10 cycles/mm was 1.04 suggesting only small error would result if one neglects the degradation by the microdensitometer (author)
Primary Subject
Source
4 refs, 3 figs, 1 tab
Record Type
Journal Article
Journal
Jurnal Fizik UTM; ISSN 0128-8644;
; v. 5(1); p. 1-8

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] For intensity-modulated radiation therapy (IMRT), a simple technique is described which splits any NxN matrix I of fluences into two mathematically equivalent matrices IA and IB summing to 2I, each of which requires considerably fewer segments to deliver IMRT using the jaws-plus-mask technique (Webb 2002b). When IA and IB are delivered alternately at fractions throughout the treatment, the total number of field segments required is between 1/2 and 2/3 that of delivering matrix I when unadjusted. (author)
Primary Subject
Secondary Subject
Source
S0031-9155(02)37733-9; Available online at the Web site for the journal Physics in Medicine and Biology (ISSN 1361-6560) http://www.iop.org/; Country of input: International Atomic Energy Agency (IAEA)
Record Type
Journal Article
Journal
Physics in Medicine and Biology; ISSN 0031-9155;
; v. 47(17); p. N217-N222

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Kota, J.; Levy, E.H.; Owens, A.J.
Conference papers. 17. International cosmic ray conference, Paris, 13-25 July 19811981
Conference papers. 17. International cosmic ray conference, Paris, 13-25 July 19811981
AbstractAbstract
No abstract available
Primary Subject
Source
CEA, 75 - Paris (France); International Union of Pure and Applied Physics; 544 p; ISBN 2-7272-0059-5;
; 1981; v. 3 p. 201; Commissariat a l'Energie Atomique; Paris, France; 17. International cosmic ray conference; Paris, France; 13 - 25 Jul 1981; Sold by Reidel, Dordrecht, Netherlands; Published in abstract form only.

Record Type
Book
Literature Type
Conference
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] A blank extender module used to mount an instrument module in front of its console for repair or test purposes has been equipped with a rotatable mount and means for locking the mount at various angles of rotation for easy accessibility. The rotatable mount includes a horizontal conduit supported by bearings within the blank module. The conduit is spring-biased in a retracted position within the blank module and in this position a small gear mounted on the conduit periphery is locked by a fixed pawl. The conduit and instrument mount can be pulled into an extended position with the gear clearing the pawl to permit rotation and adjustment of the instrument
Original Title
Patent
Source
4 Nov 1975; 4 p; US PATENT DOCUMENT 3,917,369; PAT-APPL-500,708.
Record Type
Patent
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Gold, R.E.; Dodson-Prince, H.W.; Hedeman, E.R.; Roelof, E.C.
Conference papers. 17. International cosmic ray conference, Paris, 13-25 July 19811981
Conference papers. 17. International cosmic ray conference, Paris, 13-25 July 19811981
AbstractAbstract
No abstract available
Primary Subject
Secondary Subject
Source
CEA, 75 - Paris (France); International Union of Pure and Applied Physics; 544 p; ISBN 2-7272-0059-5;
; 1981; v. 3 p. 214; Commissariat a l'Energie Atomique; Paris, France; 17. International cosmic ray conference; Paris, France; 13 - 25 Jul 1981; Sold by Reidel, Dordrecht, Netherlands; Published in abstract form only.

Record Type
Book
Literature Type
Conference
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
No abstract available
Primary Subject
Source
CEA, 75 - Paris (France); International Union of Pure and Applied Physics; 544 p; ISBN 2-7272-0059-5;
; 1981; v. 3 p. 339; Commissariat a l'Energie Atomique; Paris, France; 17. International cosmic ray conference; Paris, France; 13 - 25 Jul 1981; Sold by Reidel, Dordrecht, Netherlands; Published in abstract form only.

Record Type
Book
Literature Type
Conference
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
1 | 2 | 3 | Next |