An improved image registration method is proposed based on mutual infor- mation with hybrid optimizer. Firstly, mutual information measure is combined with morphological gradient information. The essence of the gradie...
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An improved image registration method is proposed based on mutual infor- mation with hybrid optimizer. Firstly, mutual information measure is combined with morphological gradient information. The essence of the gradient information is that locations a large gradient magnitude should be aligned, but also the orientation of the gradients at those locations should be similar. Secondly, a hybrid optimizer combined PSO with powell algorithm is proposed to restrain local maxima of mutual information function and improve the registration accuracy to sub-pixel level. Lastly, muhlresolution data structure based on Mallat decomposition can not only improve the behavior of registration function, but also improve the speed of the algorithm. Experimental results demonstrate that the new method can yield good registration result, superior to traditional optimizer with respect to smoothness and attraction basin as well as convergence speed.
A hybrid optimal algorithm, named the SAA-PA in brief, based on the simulated annealing algorithm （SAA） and the powell algorithm （PA） is proposed. The proposed algorithm puts the random search strategy of the SAA ...
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A hybrid optimal algorithm, named the SAA-PA in brief, based on the simulated annealing algorithm （SAA） and the powell algorithm （PA） is proposed. The proposed algorithm puts the random search strategy of the SAA into the PA, which can prevent optimizing courses from trapping in local optima. The SAA-PA can effectively solve multimodal optimization in the distributed multi-pump Raman amplifier （DMRA）. Optimal results show that, under the conditions of the on-off gain of 10 dB, the gain bandwidth of larger than 80 nm and the fiber length of 80 km, the gain ripple of less than 1.25 dB can be designed from the DMRA with only four backward pumps after the optimization of the proposed SAA-PA. Compared with the pure SAA, the SAA-PA can attain a lower gain ripple with the same number of pumps. Also, the relationship between the optimal signal bandwidth and the number of pumps can be simulated numerically with the SAA-PA.
Multimodality medical image registration gives insight to anatomical and functional information, which assist diagnosis and therapy planning in medicine. Registration and consecutive visualization all
Multimodality medical image registration gives insight to anatomical and functional information, which assist diagnosis and therapy planning in medicine. Registration and consecutive visualization all
The goal of source localization in the brain is to estimate a set of parameters that can represent the characteristics of the source. One of the parameters is the source number. In order to determine the dipole number...
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The goal of source localization in the brain is to estimate a set of parameters for representing source characteristics;one of such parameters is the source number. We here propose a method combining the powell algori...
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The goal of source localization in the brain is to estimate a set of parameters for representing source characteristics;one of such parameters is the source number. We here propose a method combining the powell algorithm with the information criterion method for determining the optimal dipole number. The potential errors can be calculated by the powell algorithm with the concentric 4-sphere head model and 32 electrodes, then the number of dipoles is determined by the information criterion method with the potential errors mentioned above. This method has the advantages of a high identification accuracy of dipole number and a small number of EEG data because in this method: (1) only one EEG topography is used in the computation, (2) 32 electrodes are used to obtain the EEG data, (3) the optimal dipole number can be obtained by this method. In order to prove our method to be efficient, precise and robust to noise, 10% white noise is introduced to test this method theoretically. Some investigations are presented here to show our method is an advanced approach for determining the optimal dipole number.
Information from the many kinds of spectroscopy used by chemists and physicists is fundamental to our understanding of the structure of materials. Numerical techniques have an important role to play in the augmentatio...
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Information from the many kinds of spectroscopy used by chemists and physicists is fundamental to our understanding of the structure of materials. Numerical techniques have an important role to play in the augmentation of the instrumentation and technology available in the laboratory, but are frequently viewed as separate from the laboratory procedures. We describe an integrated PC-based approach for obtaining directly the parameter estimates of transition types in piezo-spectroscopic measurements of crystalline materials. Typically, the analyses in question are required to handle complex secular matrices, to distinguish between components in the experimental results, and to identify the transition types as rapidly and as efficiently as possible. The method described, based on providing a discrete shell to the powell algorithm, is shown to give both accurate identification of the transition type in the case, of new data and improved fits (i.e. reduction in residual variation) when compared with results obtained via standard procedures. In addition it is flexible with respect to the language used and possesses a high degree of portability. We illustrate the success of the approach using (i) data previously reported on the solution of a trigonal defect which includes both mixing of states and spin orbit interactions and (ii) new data obtained for a defect related to beryllium impurities in silicon.
Three optimization procedures are examined for their utilization in determining the optimum density matrix for a single determinant wave function. The total energy of a molecular system is written as a function of the...
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Three optimization procedures are examined for their utilization in determining the optimum density matrix for a single determinant wave function. The total energy of a molecular system is written as a function of the density matrix and then optimized subject to the constraints of idempotency and total electron population. This direct calculation of the density matrix (DCDM) method was studied in an attempt to have a formalism which would avoid convergence problems associated with the self-consistent field (SCF) cycle, and which would be applicable to large molecular systems. The optimization procedures studied were the powell algorithm, Gauss-Jordan reduction, and dynamic programming. Computational factors studied include convergence criteria, stepsize, and weight factors for constraint equation penalty functions. The application considered is for HF. An ab-initio SCF method was used to obtain initial values for the density matrix, and its SCF results were compared to corresponding DCDM predictions. Approximations of the quadratic two-electron energy contributions will be necessary to apply dynamic programming, but this appears to be the method most applicable to large molecular systems if an acceptable approximation can be found. Gauss-Jordan reduction is an applicable technique, but probably not for large molecular systems. BOTM appears to be the method most applicable without introducing approximations, but weight factors for the penalty functions will have to be more efficiently determined as Lagrange multipliers, and this addition would result in a technique probably not applicable to large molecular systems.
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