− Static expansion systems are used to generate known pressures in the high and medium vacuum range. In these systems the volume ratios are the crucial parameters and have to be determined very accurately. For this task different methods can be used. We have used the gas accumulation method with a dead weight pressure balance, a force-balanced piston gauge (FPG) and a differential pressure tran...

This work investigates evaporation kinetics — the relation between the surface temperature and pressure during excimer laser ablation. Nickel targets are ablated by excimer laser pulses in a laser fluence range between 1 and 6 J/cm2, with the upper limit exceeding the threshold of phase explosion (5 J/cm2). The surface pressure is determined with a polyvinylidene fluoride (PVDF) piezoelectric t...

Hot surface ignition was examined using a variety of heat sources in a series of premixed hydrocarbon, hydrogen, and air mixtures. Building off previous work, hexane-air, heptane-air and hydrogen-air experiments were performed in addition to the eventual hexane-hydrogen-air mixtures. Using high-speed schlieren photography, thermocouples, and a fast-response pressure transducer, flame characteri...

According to previous investigations by Leanderson, Sundberg, & von Euler, subglottal pressure in singing is adapted to pitch and loudness. Thus, wide musical intervals and great, sudden changes of loudness were found to be associated with substantial and precise pressure changes. In this study, we will focus on the significance to subglottal pressure of smaller, but equally important effects, ...

We studied 50 patients with fractures of the femoral neck, 33 intracapsular and 17 extracapsular. Intraosseous pressure was measured by a transducer within the bone to quantify blood flow, and intracapsular pressure by a needle introduced into the joint space. The mean intracapsular pressure was lower in the extracapsular fractures. In these, the mean intraosseous pressure in the femoral head w...

This work presents a single-chip sub-mm3 wireless pressure sensor suitable for tire pressure monitoring. The dynamic behavior and safety of an automobile tire is closely dependent on its inflation pressure: maintaining the manufacturerrecommended pressure is essential to prevent tire failure, provide stability, improve fuel efficiency and tire-life, and to reduce CO2 emissions [1]. Thus, Tire-P...

This paper presents a theoretical model of the dynamics of liquid flow in an angular accelerometer comprising a porous transducer in a circular tube of liquid. Wave speed and dynamic permeability of the transducer are considered to describe the relation between angular acceleration and the differential pressure on the transducer. The permeability and streaming potential coupling coefficient of ...

Transducer arrays are commonly analyzed by the finite element method (FEM) with high accuracy, but it is costly, particularly when having flexible surrounding structures. In this study, we developed an equivalent circuit (EC)-based model of array transducers structures for effective analysis. The impedance matrix was first constructed coupling electrical, mechanical impedance, and acoustic radi...

This study aimed to develop an optimal methodology for the design of a miniaturized, 1–3 piezoelectric composite focused ultrasound transducer. Miniaturized (FUS) devices, generally guided through catheters, have received considerable attention in biomedical and fields as they can overcome technical restrictions typical FUS transducers. However, miniaturized transducers cannot readily generate ...

Several approaches for simulating ultrasound are available. The main tools are Finite or Boundary element methods and the spatial impulse response methods. Finite and Boundary Element methods are the most flexible but also the most computationally expensive tools available. On the other hand the spatial impulse response is restricted only to linear acoustic problem, but with low computational d...