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121.
122.
S M Sheikholeslami 《Pramana》1997,48(3):837-848
We study here the Cabibbo enhanced charmed baryon decays in theSU(4) semidynamical model. The weak Hamiltonian 20″ + 15 + 45 + 45* can have the parity violating amplitude for charmed baryon
decays. Decay width and α for some modes are also calculated. 相似文献
123.
This study is devoted to fuzzy rule based modelling of multiple-input single-output nonlinear numerical relationships. The model under investigation is viewed as a collection of conditional statements “if state Ωi then y = gi(x, ai)”, i = 1, 2,…, N with Ωi being a fuzzy relation defined in the space of the input variables. In contrast to the commonly encountered identification approach that is dwelled upon discrete experimental data, the one proposed in this study is concerned with explicitly articulated nonlinear input-output relationship. The main thrust is in the development of a fuzzy partition of the input variables completed through a sequence of fuzzy relations rather than Cartesian products of fuzzy sets. This approach allows us to maintain the number of necessary rules under control and avoid a combinatorial explosion otherwise inevitable in situations of highly multivariable functions. Introduced are criteria of separability and function variability whose objective is to guide a distribution and granularity of the linguistic labels forming the condition part of the rules. 相似文献
124.
Antonio Jiménez-Martínez 《International Journal of Game Theory》2006,34(3):425-442
We propose a two-person game-theoretical model to study information sharing decisions at an interim stage when information is incomplete. The two agents have pieces of private information about the state of nature, and that information is improved by combining the pieces. Agents are both senders and receivers of information. There is an institutional arrangement that fixes a transfer of wealth from an agent who lies about her private information. In our model, we show that (1) there is a positive relation between information revelation and the amount of the transfers, and (2) information revelation has a collective action structure, in particular, the incentives of an agent to reveal decrease with respect to the amount of information disclosed by the other. 相似文献
125.
Paul Marriott 《Annals of the Institute of Statistical Mathematics》2007,59(1):95-110
Local mixture models have proved useful in many statistical applications. This paper looks at ways in which the local assumption,
which is used in an asymptotic approximation, can be relaxed in order to generate a much larger class of models which still
have the very attractive geometric and inferential properties of local mixture models. The tool used to develop this large
class of models is the Karhunen–Loève decomposition. Computational issues associated with working with these models are also
briefly considered. 相似文献
126.
Dipak Ghosh Argha Deb Swarup Ranjan Sahoo Kanchan Kumar Patra Prabir Kumar Haldar Jayita Ghosh 《Czechoslovak Journal of Physics》2002,52(6):789-794
An analysis of data of target fragments of 28Si-AgBr (at 14.5 AGeV) reveals the existence of emission asymmetry in the azimuthal plane, which is found to depend on the number of target fragments. The comparison with the data of 32S-AgBr (at 200 AGeV) and 16O-AgBr (at 60 AGeV) interactions indicates that emission asymmetry depends on the projectile mass and energy. 相似文献
127.
128.
The pre-scission neutrons measured in the reactions 16O+181Ta and 19F+178Hf are studied via a Langevin equation coupled with a statistical decay model.We find that because of the mass asymmetry of different entrance channels,the spin distributions of compound nuclei would be different,consequently,the measured neutrons in these two reactions would also different.This means that the entrance channel will affect the particle emission in the fission process of hot nuclei. 相似文献
129.
Nigel J. Newton 《Journal of statistical physics》2008,133(4):711-737
This paper connects non-equilibrium statistical mechanics and optimal nonlinear filtering. The latter concerns the observation-conditional
behaviour of Markov signal processes, and thus provides a tool for investigating statistical mechanics with partial observations. These allow entropy
reduction, illustrating Landauer’s Principle in a quantitative way.
The joint process comprising a signal and its nonlinear filter is irreversible in its invariant distribution, which therefore
corresponds to a non-equilibrium stationary state of the associated joint system. Macroscopic entropy and energy flows are identified for this state. Since these are driven by observations internal to the system, they do not cause entropy increase, and so the joint system makes statistical mechanical sense in reverse
time.
Time reversal yields a dual system in which the signal and filter exchange roles. Despite the structural similarity of the original and dual systems,
there is a substantial asymmetry in their complexities. This reveals the direction of time, despite the systems being in stationary
states that do not produce entropy.
This work was partially supported by Leverhulme Trust Research Fellowship 2003/0426, by MURI Grant F49620-02-1-0325 (Complex
Adaptive Networks for Co-operative Control), by ARO-MURI Grant DAAD19-00-1-0466 (Data Fusion in Large Arrays of Microsensors
(sensor web)) and by NSF-ITR Grant CCR-0325774 Collaborative Research: New Approaches to Experimental Design and Statistical
Analysis of Genomic and Structural Biological Data from Multiple Sources. 相似文献
130.
K. C. Chu 《Journal of Optimization Theory and Applications》1978,25(1):139-160
This paper investigates the problem of unconstrained optimization when there is only partial information on the random parameters in the objective function. The relation between the optimization performance and the available information is established. The best information structure design with fixed rank is described. The designing procedure is set up in such a way that successive information augmentation or deletion can be considered. The procedure can also be extended to multiperson decision problems. 相似文献