A description of model 3B of the multipurpose ventricular actuating system

The multipurpose ventricular actuating system is a pneumatic signal generating device that provides controlled driving pressures for actuating pulsatile blood pumps. Overall system capabilities, the timing circuitry, and calibration instruction are included

Electronic circuit detects left ventricular ejection events in cardiovascular system

Electronic circuit processes arterial blood pressure waveform to produce discrete signals that coincide with beginning and end of left ventricular ejection. Output signals provide timing signals for computers that monitor cardiovascular systems. Circuit operates reliably for heart rates between 50 and 200 beats per minute

Control system for an artificial heart

Inexpensive industrial pneumatic components are combined to produce control system to drive sac-type heart-assistance blood pump with controlled pulsatile pressure that makes pump rate of flow sensitive to venous /atrial/ pressure, while stroke is centered about set operating point and pump is synchronized with natural heart

Circuit for detecting initial systole and dicrotic notch

Circuitry is disclosed for processing an arterial pressure waveform to produce during any one cycle a pulse corresponding to the initial systole and a pulse corresponding to the dicrotic notch. In a first channel, an electrical analog of the arterial pressure waveform is filtered and then compared to the original waveform to produce an initial systole signal. In a second channel, the analog is differentiated, filtered, and fed through a gate controlled by pulses from the first channel to produce an electrical pulse corresponding to the dicrotic notch

Automatic controllers for the Apollo LCG Final report

Automatic controllers for liquid cooling garment of Apollo full pressure sui

On Setting Apartment Rental Rates: A Regression-Based Approach

This study presents a regression-based analysis of apartment rents for a cross-section of properties located in an "edge city" submarket. It attempts to provide a solution for owners and managers of apartments to the thorny problem of setting a property's rental rate. The approach used in this analysis differs from previous studies in at least three important respects: (1) vacancy is treated as part of the dependent variable, (2) the property-specific rental rate generated by the regression analysis is compared to the property's actual effective rent, and (3) each property in the submarket is ranked by the difference between its actual effective rent and its characteristic-adjusted effective rent. This is then followed by several observations concerning the advantages and disadvantages of such an analysis in a practical setting.

Threshold detection in an on-off binary communications channel with atmospheric scintillation

The optimum detection threshold in an on-off binary optical communications system operating in the presence of atmospheric turbulence was investigated assuming a poisson detection process and log normal scintillation. The dependence of the probability of bit error on log amplitude variance and received signal strength was analyzed and semi-emperical relationships to predict the optimum detection threshold derived. On the basis of this analysis a piecewise linear model for an adaptive threshold detection system is presented. Bit error probabilities for non-optimum threshold detection system were also investigated