Pneumatically-driven left ventricular assist devices (LVADs) are widely used because they are lower in cost and simpler in operability in comparison with mechanically-driven devices. However, some problems such as the damage of their diaphragms in the devices have been pointed out. In this study, an evaluation program including FEM analysis, in which the NIPRO-LVAD is selected as a sample of a ...

[Purpose] This study aims to analyze the effect that moderate to severe chronic obstructive pulmonary disease (COPD) has on the respiratory synergist muscles. The results will provide basic data that can be used in the clinical management of COPD. [Subjects and Methods] The subjects in the study were 47 male patients with COPD between 55 and 70 years old who were treated in a medical institutio...

Film bulk acoustic resonators (FBARs) are widely applied in mass bio-sensing and pressure sensors, owing to their extreme sensitivity and integration ability, and ability to miniaturize circuits. A volatile organic compound (VOC) sensor with a polymer-coated diaphragm, using FBARs as a strain sensing element is proposed and optimized. This vapor sensor is based on organic vapor-induced changes ...

Studying complex thorax breating motion is an important research topic for accurate fusion of functional and anatomical data, radiotherapy planning or reduction of breathing motion artifacts. We investigate segmented CT lung, airway and diaphragm surfaces at several different breathing states between Functional Residual and Total Lung Capacity. In general, it is hard to robustly derive correspo...

Title of Document: THERMO-MECHANICAL DESIGN STUDY OF FIBER OPTIC PRESSURE SENSOR DIAPHRAGMS. Yasir Majeed, Master of Science, Mechanical Engineering, 2009 Directed By: Professor Abhijit Dasgupta, Department of Mechanical Engineering This thesis parametrically explores the nonlinear design sensitivity of a fiber optic pressure sensor (FOPS), based on selected thermo-mechanical failure mechanisms...

This paper presents a micro cell compression stimulator for evaluating real-time cellular responses to compression stimuli. The device was produced by a micro three-dimensional structure fabrication process using multiple exposures to the photoresist. The device consists of a pressure inlet port, cell inlet ports, a gasket, microchannels, cell culture chambers, and a diaphragm on the culture ch...

This paper describes vibration analysis using the finite element method for a small earphone, especially for the diaphragm shape with a low-rigidity. The viscoelastic diaphragm is supported by multiple nonlinear concentrated springs with linear hysteresis damping. The restoring forces of the nonlinear springs have cubic nonlinearity. The finite elements for the nonlinear springs with hysteresis...

Reinforcement of pit bottom soil has been utilized in subway deep foundation-pit engineering soft-soil areas. This study proposes an improved excavation model to better investigate the effect reinforcement at a on deformation subway’s foundation pits. The strength parameters reinforced could be obtained through cone penetration test before and after pit-bottom-soil reinforcement. results show t...

This paper describes the development of a new piezohydraulic actuator for broadband microjet flow control applications. The actuator utilizes a lead zirconate titanate (PZT) stack actuator and a hydraulic amplification design to achieve relatively large displacements in a compact actuator to control flow through a microjet orifice. Displacement amplification of 81 times the stack actuator displ...

This paper gives an overview of a deep drawing process by pressurized liquid medium separated from the sheet by a rubber diaphragm. Hydroforming deep drawing processing of sheet metal parts provides a number of advantages over conventional techniques. It generally increases the depth to diameter ratio possible in cup drawing and minimizes the thickness variation of the drawn cup. To explore the...