In single particle reconstruction (SPR) from cryo-electron microscopy (EM), the 3D structure of a molecule needs to be determined from its 2D projection images taken at unknown viewing directions. Zvi Kam showed already in 1980 that the autocorrelation function of the 3D molecule over the rotation group SO(3) can be estimated from 2D projection ...
Creator:
Zhang, Teng (University of Central Florida)
Created:
2016-11-15
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk we will discuss low-complexity algorithms for solving large-scale convex optimization problems. Such algorithms include: gradient projection, proximal gradient, Iterative Shrinkage-Thresholding (ISTA), Nesterov's acceleration, and Alternating Direction Method of Multipliers (ADMM). The emphasis of the discussion will be placed on th...
Creator:
Zhang, Shuzhong (University of Minnesota, Twin Cities)
Created:
2016-08-01
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk we will introduce conic optimization models, in particular second-order cone programming (SOCP) and semidefinite programming (SDP). We will discuss various applications of these new optimization models. Conic duality theory will be introduced as well. Finally we will introduce the so-called central path following method for solving ...
Creator:
Zhang, Shuzhong (University of Minnesota, Twin Cities)
Created:
2016-08-03
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
In this talk we discuss computational issues related to low-rank tensor completion and decomposition problems. Computing the so-called CP rank of a given tensor is already notoriously difficult, let alone the completion or decomposition models where the CP-rank plays the role of a regularization function. In this talk, we introduce various matri...
Creator:
Zhang, Shuzhong (University of Minnesota, Twin Cities)
Created:
2018-05-17
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
This talk presents two parts of results related to tensor computations. The first part is on a new matricization approach, resulting in lower and upper approximations for the CP-rank. In this part, theoretical properties of the new ranks (to be called the M-ranks) will be discussed, with applications to solve the low CP-rank tensor completion pr...
Creator:
Zhang, Shuzhong (University of Minnesota, Twin Cities)
Created:
2016-01-28
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Deep generative networks have achieved great success in high dimensional density approximation, especially for approximating the distributions of natural images and languages. In this talk, we propose to leverage their approximation capability to approximate posterior distributions in Bayesian Inverse Problems (BIPs). To train deep generative ne...
Creator:
Zhang, Pengchuan (Microsoft Research)
Created:
2018-10-22
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
A dynamic treatment regime is a sequence of decision rules, each corresponding to a decision point, that determine that next treatment based on each individual’s own available characteristics and treatment history up to that point. We show that identifying the optimal dynamic treatment regime can be recast as a sequential optimization problem ...
Creator:
Zhang, Min (University of Michigan)
Created:
2018-11-09
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Conformational searching is a core task in inverse molecularkinematics. Algorithmic improvements affecting either the speed orquality of conformational searching will have a profound impact onapplications including ligand-receptor docking, ab initio predictionof protein structure, and protein folding. In this talk, we focus on aspecific geometry...
Creator:
Zhang, Ming (University of Texas)
Created:
2007-06-01
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
Divergence functions, as a proximity measure on a smooth manifold and often surrogate to the (symmetric) metric function, play an important role in machine learning, statistical inference, optimization, etc. This talk will review the various geometric structures induced from a divergence function defined on a manifold. Most importantly, a Rieman...
Creator:
Zhang, Jun (University of Michigan)
Created:
2013-10-28
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.
The locomotion of most fish and birds is realized by flapping wings or fins transverse to the direction of travel. Here, we study experimentally the dynamics of a wing that is flapped up and down but is free to move in the horizontal direction. In this table-top prototype experiment, we show that flapping flight occurs abruptly at a critical fla...
Creator:
Zhang, Jun (New York University)
Created:
2006-06-28
Contributed By:
University of Minnesota, Institute for Mathematics and its Applications.