By combining the aeroelastic and vortex-forced flutter modes of a thin plastic strip, its oscillation frequency can be confined to scale monotonically with fluid velocity. This principle has been used to produce a low-cost, mm-scale anemometer that measures air speed to ±(5% + 0.5m/s) from 118m/s. The device uses a 2mm slot-type photointerrupt detector to monitor the fundamental frequency of a ...

The transonic flutter of the aerodynamic control surfaces supersonic and hypersonic aircraft refers to those phenomena dynamic aeroelasticity, assessment whichin a flight experiment is dangerous. Since there still no universally accepted mathematical model occurrence this phenomenon, tests dynamic-like models in wind tunnels can be classified as basic safe methods for evaluating characteristics...

In this study, with the help of three-degree-of-freedom random forced vibration device developed independently by Tongji University, high-precision measurement bridge aerodynamic force under large torsional amplitude was realized, and a potential energy spectrum established in consideration evolution effect that varies reduced velocity. As result, new research strategy for nonlinear flutter gir...

Eyelets, capstans and cylindrical surfaces are often used in thread, fiber and paper handling machinery to guide the axially moving element. In addition to providing positional control, these “guides” introduce dry friction forces that alter the vibration and stability characteristics of the system. This paper examines the lateral response of a string that slides through an elastically supporte...

Studies were performed using bipolar atrial wire electrodes to record atrial electrograms and to pace the atria in 27 patients who developed atrial flutter after open heart surgery. Two types of atrial flutter, classic or type I atrial flutter, and type II atrial flutter, were identified. Both types of atrial flutter were characterized by uniformity of the beat-to-beat atrial cycle length, morp...

OBJECTIVE To develop new electrocardiographic (ECG) criteria for the differentiation between counterclockwise and clockwise atrial flutters. BACKGROUND Traditionally, the ECG differentiation between counterclockwise and clockwise atrial flutters is based on the flutter wave polarity in the inferior leads. However, determination of flutter wave polarity is subjective and sometimes difficult, e...

BACKGROUND Right atrial flutter cycle length can prolong in the presence of antiarrhythmic drug therapy. We hypothesized that the cycle length of right atrial isthmus dependent flutter would correlate with right atrial cross-sectional area measurements. METHODS 60 patients who underwent ablation for electrophysiologically proven isthmus dependent right atrial flutter, who were not on Class I ...

In the course of some experiments on anesthetized dogs and cats concerned with the production experimentally of ventricular flutter and ventricular fibrillation, Fastier and Smirk (1948) noted that R waves sometimes appeared on the descent of the antecedent T waves, shortly before the onset of veittricular flutter. The flutter was induced by a substance amarin * which had been found by one of u...

Atrial flutter (AFL) is a common arrhythmia in clinical practice. Several experimental models such as tricuspid regurgitation model, tricuspid ring model, sterile pericarditis model and atrial crush injury model have provided important information about reentrant circuit and can test the effect of antiarrhythmic drugs. Human atrial flutter has typical and atypical forms. Typical atrial flutter ...

Certain characteristics of aconitine-induced auricular arrhythmias in dogs and the responses of aconitine-induced flutter to various experimental procedures and to drugs are described. In certain experiments there was evidence that a secondary flutter mechanism had developed which, in some instances, resembled flutter of circus-movement origin. When aconitine-induced and circus-movement flutter...