In a recent paper by Lyon et al. (Flow through Collapsible Tubes at Low Reynolds Numbers. Circ Res 47: 68-73, 1980), the authors contend that waterfall models adequately predict flow through a Starling resistor only for Reynolds numbers <1. Their basic conclusion was that caution should be used when applying waterfall models to the mammalian circulatory system since Reynolds numbers are usually...

INTRODUCTION Continuous positive airway pressure (CPAP) is used in air ambulances to treat patients with impaired oxygenation. Differences in mechanical principles between CPAP devices may affect their performance at different ambient air pressures, as will occur in an air ambulance during flight. METHODS Two different CPAP systems, a threshold resistor device and a flow resistor device, at s...

We propose the notion of {\it resistance of a graph} as an accompanying notion of the structure entropy to measure the force of the graph to resist cascading failure of strategic virus attacks. We show that for any connected network $G$, the resistance of $G$ is $\mathcal{R}(G)=\mathcal{H}^1(G)-\mathcal{H}^2(G)$, where $\mathcal{H}^1(G)$ and $\mathcal{H}^2(G)$ are the one- and two-dimensional s...

The flow-resistive characteristics of a variety of commercially available expiratory positive-pressure valve systems used to provide continuous positive airway pressure (CPAP) and positive end-expiratory pressure were evaluated. One flow-resistor and seven threshold-resistor expiratory pressure valve systems were set at 5, 10, 15, 20, and 25 cm H2O of expiratory pressure, and sinusoidal exhaled...

We demonstrate the novel and compact implementation of literal gates with one literal window and two literal windows using only resonant tunneling diodes (RTDs). The proposed circuit consists of only three RTDs and one resistor for one literal window and four RTDs and one resistor for two literal windows, with the configuration of a series-connected RTD pair and a series-connected RTD and a res...

INTRODUCTION Fluid responsiveness prediction is difficult in spontaneously breathing patients. Because the swings in intrathoracic pressure are minor during spontaneous breathing, dynamic parameters like pulse pressure variation (PPV) and systolic pressure variation (SPV) are usually small. We hypothesized that during spontaneous breathing, inspiratory and/or expiratory resistors could induce h...

BACKGROUND Positive-expiratory-pressure (PEP) therapy uses positive airway pressure generated by a either a fixed-orifice resistor or a threshold resistor. We hypothesized that tubing diameter and length, and the diameter of the PEP bottle's air-escape orifice would impact the PEP pressure delivered to the airway and determine whether the PEP bottle acts as a threshold resistor or a fixed-orifi...

-Memristor is the fourth fundamental passive element after resistor, inductor and capacitor. Memristor is memory resistor which is two terminal device. This semiconductor device is statistically proved by a student in china Leon Chua in 1971. And discovered by scientist. R.Stanley Williams and its team in April 30,2008 in lab of HP. It consist a semiconductor of titanium dioxide in which one ha...

An approach by Stephen is used to investigate the critical properties of randomly diluted resistor networks near the percolation threshold by means of renormalized field theory. We reformulate an existing field theory by Harris and Lubensky. By a decomposition of the principal Feynman diagrams we obtain a type of diagrams which again can be interpreted as resistor networks. This new interpretat...

The ancient Babylonians had an iterative technique for numerically approximating the values of square roots. Their method can be physically implemented using series and parallel resistor networks. A recursive formula for the equivalent resistance Req is developed and converted into a nonrecursive solution for circuits using geometrically increasing numbers of identical resistors. As an example,...