In this paper, we consider a kind of area preserving non-local flow for convex curves in the plane. We show that the flow exists globally, the length of evolving curve is non-increasing, and the curve converges to a circle in C∞ sense as time goes into infinity.

We propose a segmentation method for vector fields that employs geometrical curve attributes to classify the behavior of the integral curves. In particular, we assign to a given spatio-temporal position the attribute value associated with the integral curve initiated at that point. With this attribute information, our segmentation strategy first performs a region classification. Then, connected...

Thus Tf(x) can be viewed as averaging the function f over the curve t → γ(x, t) with respect to the fractional integral kernel k(t). The condition γ(x, 0) = x is a way of saying the curve at x is ”centered at x”, and the condition that ∂γ ∂t (x, t) 6= 0 ensures that the averaging is smooth. In fact, the arguments of this paper will go through with k(t) replaced by k(x, t) satisfying appropriate...

The determination of hemodynamic significance of coronary artery lesions from cardiac computed tomography angiography (CCTA) based on flow simulations has the potential to improve CCTA’s specificity, thus resulting in improved clinical decision making. Accurate coronary lumen segmentation required for flow simulation is challenging due to several factors. Specifically, the partial-volume (PV) e...

AIM We assessed the management and outcomes of non-ST segment elevation myocardial infarction (NSTEMI) patients randomly assigned to fractional flow reserve (FFR)-guided management or angiography-guided standard care. METHODS AND RESULTS We conducted a prospective, multicentre, parallel group, 1 : 1 randomized, controlled trial in 350 NSTEMI patients with ≥1 coronary stenosis ≥30% of the lume...

Two novel methods for image feature extraction based on fractional differentiation are presented in this paper. The first method is the feature extraction of fusing multi-direction CRONE operators. In this method, the fractional differential CRONE mask is generalized to eight directions at first for extracting image features; then the extracted features are tested by the statistic method and fu...

polarization for au/pb(zr ti )o /yba cu o ferroelectric capacitor has been studied and measured by pulse method. a sequence of pulses with amplitudes varying from 0 to 10 volts in 2 volt steps is applied and a conventional polarization curve is obtained by integrating the charge flow from the polarization switching induced by the voltage ramp. a value of 25?c/cm2 is measured for the saturated p...

BACKGROUND The Fractional Flow Reserve Versus Angiography for Multivessel Evaluation (FAME) 2 trial demonstrated a significant reduction in subsequent coronary revascularization among patients with stable angina and at least 1 coronary lesion with a fractional flow reserve ≤0.80 who were randomized to percutaneous coronary intervention (PCI) compared with best medical therapy. The economic and ...

OBJECTIVES This study sought to assess the impact of a wide range of mean right atrial pressure (Pra) on fractional flow reserve (FFR) measurements. BACKGROUND FFR invasively assesses the ischemic potential of coronary stenoses. FFR is calculated as the ratio of mean distal coronary pressure (Pd) to mean aortic pressure (Pa) during maximal hyperemia. The Pra is considered to have little impac...

A mathematical model based on viscoelastic fluid (fractional Oldroyd-B model) flow is considered for the peristaltic flow of chyme in small intestine, which is assumed to be in the form of an inclined cylindrical tube. The peristaltic flow of chyme is modeled more realistically by assuming that the peristaltic rush wave is a sinusoidal wave, which propagates along the tube. The governing equati...