The rotary subwoofer is a novel acoustic transducer capable of projecting infrasonic signals at high sound pressure levels. The projector produces higher acoustic particle velocities than conventional transducers which translate into higher radiated sound pressure levels. This paper characterizes measured performance of a rotary subwoofer and presents a model to predict sound pressure levels.

BACKGROUND To eliminate the influence of hydrostatic pressure, proper transducer positions for central venous pressure and pulmonary artery wedge pressure are at the uppermost blood levels of right atrium (RA) and left atrium (LA). This study was performed to investigate accurate reference levels of central venous pressure and pulmonary artery wedge pressure in the supine position. METHODS Ch...

This paper presents the experimental study of pressure and velocity fluctuations and their interdependence, in the turbulent flow impinging on arrangements of yawed circular cylinders simulating inclined tube banks with square arrangement and a pitch to diameter ratio of 1.26. Measurements were performed with hot-wires and a pressure transducer. Behaviour of fluctuating quantities is described ...

The paper is devoted to the analysis of operating cycle a high-pressure injection pump used in common rail systems. investigation based on experimental activities, and it carried out novel set-up that allows measurements instantaneous pressure piston working chamber. A single plunger has been equipped with piezo-resistive transducer which for measurement signal during operation test rig. descri...

The objective of this paper is to report the state-of-the-art of unsteady pressure measurements in pumps. Though optical techniques seem in some aspects more attracting, unsteady pressure measurements can give a detailed insight in static as well as dynamic operating behaviour of pumps. A brief description of wall mounted pressure transducers and of probes fitted with miniature pressure transdu...

CONTEXT A potential variable that could affect rate of temperature elevation with ultrasound is the pressure (mass) that is applied to the transducer head during application. Added pressure could compress the tissue, affecting density and the transmission of ultrasound energy. Little research has been completed to determine the effects of the amount of pressure applied during therapeutic ultras...

Objective(s) Calcium-channel blockers have an important role in the treatment of several cardiovascular disorders. Derivatives of 1, 4-dihydropyridine are one of the most potent calcium antagonists. In this study four novel ', 4-dihydropyridine calcium channel blockers were synthesized and their hypotensive properties were investigated in male rats. Materials and Methods Four 1, 4-dihydropyr...

Measurements of the spatial distribution of the time-averaged second-order pressure in a plane standing wave in atmospheric air are reported. Several measurement pitfalls are identified, and solutions are described. These include accounting for slight nonlinearity of the piezoresistive transducer and careful mounting of the transducer. Streaming causes extra complication when a capillary-connec...

IMPORTANCE To our knowledge, this is a report of the first implantation of a wireless intraocular pressure transducer (WIT) in a human eye. OBJECTIVE To report preliminary safety data on the WIT. DESIGN, SETTING, AND PARTICIPANT In an institutional setting, a patient with open-angle glaucoma consented to be the recipient of the WIT in one eye in an interventional study design. INTERVENTIO...

A one-dimensional (1D) Fourier-Bessel series method for computing and tuning (beamforming) the linear lossless field of flat pulsed wave annular arrays is developed and supported with both numerical simulation and experimental verification. The technique represents a new method for modeling and tuning the propagated field by linking the quantized surface pressure profile to a known set of limit...