http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : St. Gundacker (검색결과 3 건)
- 무료
- 기관 내 무료
- 유료
-
Bayesian Based Uncertainties of Neutron-Induced Reaction Cross Sections of Mn-55
H. Leeb,St. Gundacker,D. Neudecker,Th. Srdinko,V. Wildpaner 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.23
The extreme conditions in a future fusion reactor require a careful selection of materials with regard to activation and aging. Of particular interest for a proper choice is the availability of high quality evaluated nuclear cross section data files for structural materials which comprise reliable covariance matrices and cover the energy range up to at least 60 MeV, the envisaged end of the relevant spectrum of the future IFMIF facility. In this contribution emphasis is given to the generation of cross section covariance matrices for a new evaluated data file for neutron-induced cross sections of Mn-55 between 1 and 150 MeV. The evaluated file takes into account experimental data of the EXFOR data base and is generated by Bayesian statistics via the code GENEUS. Due to the scarcity of experimental data beyond 20 MeV, the prior, based on the nuclear model set of TALYS-1.0, plays an essential role for the reliability of the file in this energy regime. Therefore much effort was devoted to an optimized choice of the model parameters for the range 20 ≤ Z ≤ 28. Employing the recent formalisms a prior including parameter uncertainties and model defects was evaluated by GENEUS and used as a starting point of the evaluation process. In addition a careful analysis of experimental data was performed to estimate the covariance matrices of the experiments, which are used by GENEUS in the Bayesian procedure. The quality and the specific features of the evaluated data file and associated uncertainties are discussed.
-
Comparison of Covariance Matrices Obtained by Different Methods
D. Neudecker,St. Gundacker,Th. Srdinko,V. Wildpaner,H. Leeb 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.23
At present significant efforts in nuclear data evaluation are focused on the generation of evaluated data files which include also uncertainty information in form of covariance matrices. Several methods for the generation of covariance matrices have been worked out, ranging from Monte Carlo variation of model parameters to detailed Bayesian techniques. In this contribution cross section covariance matrices for neutron-induced reactions on Pb-208 obtained by Monte Carlo variations of model parameters are compared with the corresponding matrices obtained by strict Bayesian techniques as implemented in the code package GENEUS. Both evaluations rely on the same nuclear model, <i>i.e.</i>, TALYS-1.0, with the same parameters and account for a similar set of experimental data. Thus the comparison directly reflects the features of the different methods and allows conclusions on the reliability of the extracted uncertainty information.
-
The GENEUS Project - Development of an Evaluation Tool
H. Leeb,St. Gundacker,D. Neudecker,Th. Srdinko,V. Wildpaner 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.23
GENEUS is an acronym for 'General Nuclear Data Evaluation and Uncertainty System'. The project aims at the development of a software toperform nuclear data evaluations of cross section data within the framework ofBayesian statistics. The evaluation procedure starts with the generation ofthe prior on the basis of a given set of nuclear models. Especially, thea-priori covariance matrices due to parameter uncertainties and model defectsare determined employing the recently developed formalisms. After selection ofthe experimental data and the generation of covariance matrices associatedwith experiments a Bayesian procedure is employed to obtain evaluated datafiles, which are provided in tabular and ENDF-formatted form. Special care istaken to include correlations between experiments and a proper treatment ofsystematic errors. GENEUS is planned as an almost automatic evaluation packagewith a user-friendly handling. As a special feature it includes asoftware, which facilitates the selection of experimental data and thegeneration of associated covariance matrices. The modular concept of GENEUSallows the inclusion of up-to-date model codes, e.g. TALYS-1.0. In thiscontribution we present the concept of the code and its basic numericalimplementation, which in its first version is restricted to neutron-inducedcross sections. The specific features and capabilities of the code package areshown by the example of successfully performed evaluations with this first version ofGENEUS.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
