an essential requirement for an operating pem fuel cell is providing proper water content in the membrane. to avoid water flooding an appropriate water balance is required. here, an analytic model of a planar membrane humidifier for pem fuel cell is proposed where the effect of dimensional parameters includes membrane thickness, membrane area and channel hydraulic diameter are investigated. a n...

objectives our aim was to study the relation between vac and the parameters of myocardial mechanics using three-dimensional speckle-tracking echocardiography (3dste). patients and methods we studied 68 normal participants (mean age, 35 ± 12.2 y; 36 [53%] males). vac was measured by the ratio of arterial elastance (ea) to ventricular elastance (ees). the peak systolic value of longitudinal strai...

investment casting is a versatile manufacturing process to produce high quality parts with high dimensional accuracy. the process begins with the manufacture of wax patterns. the dimensional accuracy of the model affects the quality of the finished part. the present study investigated the control and optimization of dimensional deviations in wax patterns. a mold for an h-shaped wax pattern was ...

normal 0 false false false en-us x-none ar-sa stereolithography process limits wider applications due to low dimensional accuracy comparing with cnc. to improve accuracy and reduce part distortion, understanding the physics involved in the relationship between the setup input parameters and the part dimensional accuracy is prerequisite. in this paper, a model is proposed to find and optimize im...

We show that the three-dimensional (3-D) motion parameters of a rigid planar patch can be determined by computing the singular value decomposition (SVD) of a 3 X 3 matrix containiig the eight so called “pure parameters.” Furthermore, aside from a scale factor for the translation parameters, the number of solutions is either one or two, depending on the multiplicity of the singular values of the...

Investment casting is a versatile manufacturing process to produce high quality parts with high dimensional accuracy. The process begins with the manufacture of wax patterns. The dimensional accuracy of the model affects the quality of the finished part. The present study investigated the control and optimization of dimensional deviations in wax patterns. A mold for an H-shaped wax pattern was ...

This study investigates the free vibration of the Two-Dimensional Functionally Graded Annular Plates (2D-FGAP). The theoretical formulations are based on the three-dimensional elasticity theory with small strain assumption. The Two-Dimensional Generalized Differential Quadrature Method (2D-GDQM) as an efficient and accurate semi-analytical approach is used to discretize the equations of motion ...