To solve the/a problem of the Minimal Supersymmetric Standard Model （MSSM）, a single field S is added to build the Next Minimal Supersymmetric Standard Model （NMSSM）. Vacuum enlarged with non-zero vevs of the neut...To solve the/a problem of the Minimal Supersymmetric Standard Model （MSSM）, a single field S is added to build the Next Minimal Supersymmetric Standard Model （NMSSM）. Vacuum enlarged with non-zero vevs of the neutral-even CP is the combination of Hu, Hd and S. In the NMSSM, the Higgs sector is increased to 7 （compared with 5 hogs in the MSSM）, including three Higgs-which are the even-CP hi,2,3 （mh1〈 mh2〈 mh3）, two Higgs-which are odd-CP a1,2 （ma1 〈 ma2） and a couple of charged Higgs H^±. The decays Higgs into Higgs is one of the remarkable new points of the NMSSM. In this paper, we study the decays H^± into W^± and at. The decay width is calculated to one loop vertex correction. The numerical results are also described together with evaluations.展开更多
LSQR, a Lanczos bidiagonalization based Krylov subspace iterative method, and its mathematically equivalent conjugate gradient for least squares problems(CGLS) applied to normal equations system, are commonly used for...LSQR, a Lanczos bidiagonalization based Krylov subspace iterative method, and its mathematically equivalent conjugate gradient for least squares problems(CGLS) applied to normal equations system, are commonly used for large-scale discrete ill-posed problems. It is well known that LSQR and CGLS have regularizing effects, where the number of iterations plays the role of the regularization parameter. However, it has long been unknown whether the regularizing effects are good enough to find best possible regularized solutions. Here a best possible regularized solution means that it is at least as accurate as the best regularized solution obtained by the truncated singular value decomposition(TSVD) method. We establish bounds for the distance between the k-dimensional Krylov subspace and the k-dimensional dominant right singular space. They show that the Krylov subspace captures the dominant right singular space better for severely and moderately ill-posed problems than for mildly ill-posed problems. Our general conclusions are that LSQR has better regularizing effects for the first two kinds of problems than for the third kind, and a hybrid LSQR with additional regularization is generally needed for mildly ill-posed problems. Exploiting the established bounds, we derive an estimate for the accuracy of the rank k approximation generated by Lanczos bidiagonalization. Numerical experiments illustrate that the regularizing effects of LSQR are good enough to compute best possible regularized solutions for severely and moderately ill-posed problems, stronger than our theory, but they are not for mildly ill-posed problems and additional regularization is needed.展开更多
Focusing on the singularities of a spacecraft using control moment gyros(CMGs)to do the large angle maneuvers,a new mixture steering law is proposed to avoid the singularities.According to this method,if the CMGs are ...Focusing on the singularities of a spacecraft using control moment gyros(CMGs)to do the large angle maneuvers,a new mixture steering law is proposed to avoid the singularities.According to this method,if the CMGs are far away from the singularity,the Moore-Penrose pseudo-inverse steering law(MP)is used directly.If the CMGs are close to the singularity,instead of solving the inverse matrix,a set of optimal gimbal angles are sought for the singular measurement to reach the maximum,which can avoid the singularities.Simulations show that the designed steering law enables the spacecraft to carry out the large angle maneuver and avoid the singularities simultaneously.展开更多
文摘To solve the/a problem of the Minimal Supersymmetric Standard Model （MSSM）, a single field S is added to build the Next Minimal Supersymmetric Standard Model （NMSSM）. Vacuum enlarged with non-zero vevs of the neutral-even CP is the combination of Hu, Hd and S. In the NMSSM, the Higgs sector is increased to 7 （compared with 5 hogs in the MSSM）, including three Higgs-which are the even-CP hi,2,3 （mh1〈 mh2〈 mh3）, two Higgs-which are odd-CP a1,2 （ma1 〈 ma2） and a couple of charged Higgs H^±. The decays Higgs into Higgs is one of the remarkable new points of the NMSSM. In this paper, we study the decays H^± into W^± and at. The decay width is calculated to one loop vertex correction. The numerical results are also described together with evaluations.
基金supported by National Basic Research Program of China (Grant No. 2011CB302400)National Natural Science Foundation of China (Grant No. 11371219)
文摘LSQR, a Lanczos bidiagonalization based Krylov subspace iterative method, and its mathematically equivalent conjugate gradient for least squares problems(CGLS) applied to normal equations system, are commonly used for large-scale discrete ill-posed problems. It is well known that LSQR and CGLS have regularizing effects, where the number of iterations plays the role of the regularization parameter. However, it has long been unknown whether the regularizing effects are good enough to find best possible regularized solutions. Here a best possible regularized solution means that it is at least as accurate as the best regularized solution obtained by the truncated singular value decomposition(TSVD) method. We establish bounds for the distance between the k-dimensional Krylov subspace and the k-dimensional dominant right singular space. They show that the Krylov subspace captures the dominant right singular space better for severely and moderately ill-posed problems than for mildly ill-posed problems. Our general conclusions are that LSQR has better regularizing effects for the first two kinds of problems than for the third kind, and a hybrid LSQR with additional regularization is generally needed for mildly ill-posed problems. Exploiting the established bounds, we derive an estimate for the accuracy of the rank k approximation generated by Lanczos bidiagonalization. Numerical experiments illustrate that the regularizing effects of LSQR are good enough to compute best possible regularized solutions for severely and moderately ill-posed problems, stronger than our theory, but they are not for mildly ill-posed problems and additional regularization is needed.
基金supported by the National Natural Sciences Foundation of China(Grant No.11172036)the Excellent Young Scholars Rearch Fund of Beijing Institute of Technology(Grant No.2012YG0101)
文摘Focusing on the singularities of a spacecraft using control moment gyros(CMGs)to do the large angle maneuvers,a new mixture steering law is proposed to avoid the singularities.According to this method,if the CMGs are far away from the singularity,the Moore-Penrose pseudo-inverse steering law(MP)is used directly.If the CMGs are close to the singularity,instead of solving the inverse matrix,a set of optimal gimbal angles are sought for the singular measurement to reach the maximum,which can avoid the singularities.Simulations show that the designed steering law enables the spacecraft to carry out the large angle maneuver and avoid the singularities simultaneously.
