Background Cardiac gating in ultra high field (UHF) MRI is a challenging task due to the magnetohydrodynamic (MHD) effect [1]. The MHD effect is particularly severe at such field strengths and severely distorts the electrocardiogram (ECG). State-of-the-art ECG based gating methods which use the vectorcardiogram (VCG) [2] are thus prone to errors [1]. This work presents an approach which separat...

The study aim was to construct linear transformations for derivation of McFeeParungao vectorcardiogram (VCG) from 12 standard ECG or Frank VCG and to assess the accuracy of derived electric cardiac signals (ECS) and secondarily derived VCG parameters. A large archive of VCG data recorded in the McFee-Parungao lead system have been accumulated and analyzed in the Cardiology Research Complex (Mos...

EAELIER electrocardiographic recording procedures utilized the limb leads described by Waller and standardized by Einthoven. In 1913, Einthoven, Fahr, and de Waart made the first vectorial approach to the study of electrocardiographic potentials, using the standard limb leads to estimate the mean direction and magnitude of the electromotive forces produced by the heart in the plane denned by th...

We study mechanisms where a player’s strategy is one of his possible (payoff) types and at least one player is Knightian, that is, cannot distinguish which element of a “candidate set” with multiple types is his true type. We call such a mechanism Knightian truthful if, in all its rational plays, every player reports his own true type, if he knows it exactly, and a type in his candidate set, if...

At the very beginning of the semester, we saw an incredibly powerful tool in mechanism design: the VCG mechanism. You remember: the VCG mechanism lets us find the welfare-optimal solution for any social choice problem, and pair it with payments that makes truthful reporting of one’s preferences a dominant strategy for every player. Pretty impressive! Yet, one-shot direct revelation mechanisms a...

Consider an abstract social choice setting with incomplete information, where the number of alternatives is large. Albeit natural, implementing VCG mechanisms is infeasible due to the prohibitive communication constraints. However, if players restrict attention to a subset of the alternatives, feasibility may be recovered. This paper characterizes the class of subsets which induce an ex-post eq...