Introduction Echo-planar imaging (EPI) is a group of fast data acquisition methods commonly used in fMRI studies. It acquires multiple image lines in k-space after a single excitation, which leads to a very short scan time. A well-known problem with EPI is that it is more sensitive to distortions due to the used encoding scheme. Source of distortion is inhomogeneity in the static B0 field that ...

Given two-dimensional Riemannian manifolds $$\mathcal {M},\mathcal {N}$$ , we prove a lower bound on the distortion of embeddings {M}\rightarrow \mathcal in terms areas’ discrepancy $$V_{\mathcal {N}}/V_{\mathcal {M}}$$ for certain class functionals. For {M}} \ge 1/4$$ homotheties, provided they exist, are unique energy minimizing maps attaining bound, while \le there non-homothetic minimize...

With the evolution of technology, the maintenance of sophisticated systems is of concern for system engineers and system designers. The maintenance cost of the system depends in general on the replacement and repair policies. The system replacement may be in a strictly periodic fashion or on a random basis depending upon the maintenance policy. At failure, the repair of the system may be perfor...

Conventional algorithms for blind source separation do not necessarily work well for real-world data. One of the reasons is that, in actual applications, the mixing matrix is often almost singular at some part of frequency range and it can cause a certain computational instability. This paper proposes a new algorithm to overcome this singularity problem. The algorithm is based on the minimal di...

BACKGROUND The tuberous breast syndrome is a condition that affects young women and can bring on serious disorders of self-esteem. There are numerous surgical techniques to correct this condition, but most of them include the use of breast implants to replace lack of volume. Nowadays, patients are increasingly becoming more demanding to get a definitive solution with minimal aesthetic sequelae...