We present an efficient modal method to calculate the two-dimensional Green’s function for electromagnetics in curvilinear coordinates. For this purpose the coordinate transformation based differential method, introduced for the numerical analysis of surface-relief gratings, is directly used with perfectly matched layers (PMLs). The covariant formalism Maxwell’s equations, very convenient for t...

Chen et al. (2010) propose a unified method – coordinate-independent sparse estimation (CISE) – that is able to simultaneously achieve sparse sufficient dimension reduction and screen out irrelevant and redundant variables efficiently. However, its attractive features depend on appropriate choice of the tuning parameter. In this note, we re-examine the Bayesian information criterion (BIC) in su...

Short description: We developed a unified framework for percutaneous therapies utilizing localization frames and implemented an application using CT imaging and a robot. Description: The planning and execution of percutaneous therapies are very diverse. We investigated those that make use of a localization frame. When using a so called stereotacic frame, a base is rigidly attached to the patien...

In this paper, we study optimization methods consisting of iteratively minimizing surrogates of an objective function. By proposing several algorithmic variants and simple convergence analyses, we make two main contributions. First, we provide a unified viewpoint for several first-order optimization techniques such as accelerated proximal gradient, block coordinate descent, or FrankWolfe algori...

We describe a hybrid measured/calculated method for attenuation correction in positron emission tomography (PET). This unified reconstruction/segmentation method is based on a penalized weighted least-squares (PWLS) objective function that is minimized using iterative coordinate-descent (ICD). Two penalty functions are compared; one for a discrete object parameterization, the other for a contin...

We introduce an R package named picasso, which implements a unified framework of pathwise coordinate optimization for a variety of sparse learning problems (Sparse Linear Regression, Sparse Logistic Regression and Sparse Poisson Regression), combined with efficient active set selection strategies. Besides, the package allows users to choose different sparsityinducing regularizers, including the...

In this paper, the static and free vibration analysis of laminated shells is performed by radial basis functions collocation, according to a sinusoidal shear deformation theory (SSDT). The SSDT theory accounts for through-the-thickness deformation, by considering a sinusoidal evolution of all displacements with the thickness coordinate. The equations of motion and the boundary conditions are ob...

The growing amount of high dimensional data in different machine learning applications requires more efficient and scalable optimization algorithms. In this work, we consider combining two techniques, parallelism and Nesterov’s acceleration, to design faster algorithms for L1-regularized loss. We first simplify BOOM [11], a variant of gradient descent, and study it in a unified framework, which...

We suggest a simple grand unified theory where the fifth dimensional coordinate is compactified on an S1/(Z2 × Z ′ 2) orbifold. This model is based on the supersymmetric flipped SU(5) × U(1) grand unified theory, which can realize not only the triplet-doublet splitting but also the natural fermion mass hierarchies. The triplet-doublet splitting is realized by S1/(Z2 × Z ′ 2) orbifolding, which ...