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[en] The degree of nuclear stopping is studied by comparing the proton rapidity spectra in central collisions of 4496Ru + 4096Zr and 4096Zr + 4496Ru at incident beam energy of 400A MeV. The rapidity dependence of the proton yield ratio in two colliding systems evidences the incomplete mixing of projectile and target nucleons and the transparency. The IQMD transport model with the free nucleon-nucleon cross-section filtered by the geometrical acceptance of the FOPI detector overestimates the degree of nuclear stopping. (author)
Journal
Genshikaku Kenkyu; ISSN 0367-4169; 
; v. 44(2); p. 13-21
; v. 44(2); p. 13-21
[en] This paper reports that power reactor benchmark calculations using the advanced code package CASMO-3/SIMULATE-3 with new models have been performed for nine cycles of Chinshan Unit 1 and six cycles of Kuosheng Unit 1. The fuel reload designs include gadolinia as a burnable absorber, natural uranium axial blankets, and fuel from different vendors. The calculated results for cold critical tests and traversing in-core probe (TIP) responses are compared with measured data. These comparisons show that the new modeling accurately predicts important physics parameters for power reactors, and it is more accurate than the conventional model. However, more studies of the TIP adaption model are needed in order to gain more experience for its application
Journal
No abstract available
Journal
Transactions of the American Nuclear Society; ISSN 0003-018X; ; v. 44 p. 537-538
; v. 44 p. 537-538
[en] The Studsvik Core Management System (CASMO-3/SIMULATE-3) has been validated for application to steady-state reactor physics analyses for pressurized water reactors by demonstrating its ability to obtain accurate and reliable results for various conditions and applications. The analyses validated include global reactivity calculations such as boron letdown, low-power physics test predictions, detailed pin by pin power distribution, as well as in-core detector reaction rate calculations. The calculated results have been compared to measured data of 13 cycles for Maanshan Units 1 and 2 as well as measured critical experiments, and the accuracies of the method have been quantified. The validation results indicate that the Taiwan Power Company's steady-state reactor physics methodology performs to a level of accuracy sufficient for the intended applications, and the accuracies in general are slightly better than the world-wide applications
Journal
[en] Qualification efforts have been performed by the Taiwan Power Company (TPC) and the Institute of Nuclear Energy Research (INER) for the three-dimensional spatial kinetics code ARROTTA for light water reactor (LWR) core transient analysis. Together TPC and INER started a 5-yr project in 1989 to establish independent capabilities to perform reload design and transient analysis utilizing state-of-the-art computer programs. As part of the effort, the ARROTTA code was chosen to perform multidimensional kinetics calculations such as rod ejection for pressurized water reactors and rod drop for boiling water reactors (BWR). To qualify ARROTTA for evaluation of the Final Safety Analysis Report licensing basis core transients, ARROTTA has been benchmarked for the static core analysis against plant measured data and SIMULATE-3 predictions, and for the kinetic analysis against available benchmark problems. The static calculations compared include critical boron concentration, core power distribution, and control rod worth. The results indicate that ARROTTA predictions match very well with plant measured data and SIMULATE-3 predictions. The kinetic benchmark problems validated include the Nuclear Energy Agency Committee on Reactor Physics rod ejection problem, the three-dimensional Langenbuch-Maurer-Werner LWR rod withdrawal/insertion problem, and the three-dimensional linear regression analysis BWR transient benchmark problem. The results indicate that ARROTTA's accuracy and stability are excellent as compared with other space-time kinetics codes. It is therefore concluded that ARROTTA provides accurate predictions for multidimensional core transients for LWRs
Journal
[en] The first real size Resistive Plate Chamber (RPC) prototype of ME2/1 for the forward region of the Compact Muon Solenoid (CMS) detector was constructed at Korea Detector Laboratory (KODEL). The parallel resistive electrodes of the double gap RPC were made of bakelite whose resistivity was 5x109 Ω cm. The prototype was tested at the Gamma Irradiation Facility (GIF) of CERN in an environment of the background intensity ranging up to 1 kHz/cm2/gap. We report that the full efficiency of 98% has been achieved with time resolution of about 1 ns. These results demonstrate that such a double gap RPC is suitable for the muon trigger in the future experiments
Journal
Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment; ISSN 0168-9002; ; CODEN NIMAER; v. 443(1); p. 31-36
; CODEN NIMAER; v. 443(1); p. 31-36
[en] Aim: In order to clarify the significance of myocardial substrate utilization of energy metabolism in correlation with perfusion and function, we analyzed myocardial PET and SPECT data as a polar map, and compared those with systolic wall thickening map generated from ECG gated PET. Methods: The study included SPECT imaging of 123I 15-(p-iodophenyl)-3-methyl-pentadecanoic acid (BMIPP) and PET imaging of 13N ammonia (NH3) and 18F 2-fluoro-2-deoxy-D-glucose (FDG) in patients with coronary artery disease. ECG gated PET data were acquired for NH3 study with 10 equal samplings of cardiac cycle for 10 min. Based on the circumferential profile analysis of the short axis images, the standard polar map was generated for BMIPP, NH3, and FDG. Wall thickening (WT) map was calculated as percent increase of the counts on polar map. Results: WT map was well correlated with contrast left ventriculography (LVG). WT showed a significant positive correlation only with BMIPP, but no correlation with NH3 nor FDG. Among the segments with decreased BMIPP uptake, the segments with increased FDG accumulation demonstrated significantly better WT than those with less FDG accumulation. Conclusion: Combined analysis of BMIPP SPECT with ECG gated PET permitted direct comparison of myocardial perfusion, substrate utilization and regional wall motion. Close correlation of BMIPP uptake and systolic wall thickening map suggested the significance of fatty acid utilization as major energy substrate to maintain myocardial function. (orig.)
[de]
Einleitung: Um die Signifikanz der myokardialen Substratutilisation des Energiemetabolismus in Korrelation zu Perfusion und Funktion zu erklaeren, analysierten wir Herz-PET- und -SPECT-Daten, die in Form von Polarplots vorlagen, und verglichen diese mit Plots der systolischen Wanddickenaenderung, die aus EKG-getriggerten PET-Studien abgeleitet wurden, ueber eine auf Counts basierende Technik. Methoden: Neun Patienten mit Myokardinfarkt wurden mit 123I BMIPP-SPECT, N-13-Ammonium- und FDG-PET untersucht. EKG-getriggerte Daten wurden fuer die NH3-Studien mit 10 gleichlangen Zeitperioden pro RR-Zyklus fuer 10 Minuten aufgenommen. Die Daten wurden auch mit denen der Laevokardiographie (LVG) verglichen. Basierend auf der Analyse der zirkumferentiellen Profile der Kurzachsenschnitte wurde ein standardisierter Polarplot fuer die BMIPP-, NH3- und FDG-Szintigraphien erstellt. Wanddickenplots (WT) wurden als der prozentuale Anstieg der Counts folgenden Plots berechnet: (ES-ED)/EDx100. Die Analyse wurde fuer neun ROIs, die ueber den Polarplots plaziert wurden durchgefuehrt. Ergebnisse: Der WT-Plot korrelierte gut mit der LVG. WT zeigte nur mit BMIPP eine positive signifikante Korrelation (r=0,675, p<0,001) und keine mit NH3 und FDG. Unter den Segmenten mit vermindertem BMIPP-Uptake zeigten diejenigen mit erhoehter FDG-Aufnahme eine signifikant bessere WT, verglichen mit denen mit verminderter FDG-Akkumulation. Schlussfolgerungen: Die kombinierte Analyse der BMIPP-SPECT und der EKG-getriggerten PET erlaubt die simultane Bildgebung von Perfusion, Metabolismus und regionaler Wandbewegung. Die enge Korrelation zwischen der BMIPP-Aufnahme und der systolischen Wandverdickung legt signifikant nahe, dass die Utilisation freier Fettsaeuren als Hauptenergiesubstrat dient, um die myokardiale Funktion aufrechtzuerhalten. (orig.)Journal
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