Knowing loss coefficients of duct fittings is crucial for designing a duct network for HVAC systems. Traditionally, the coefficients have been obtained using experimental measurements according to AHSRAE Standard 120, a process which is time consuming and expensive. An alternative is to use CFD, but this has uncertainty due to the approximations used in modeling turbulence. This study first val...

Hydrophobic surfaces with microscale roughness can be rendered ultrahydrophobic by the addition of sub-micron scale roughness. A simple yet highly effective concept of fabricating hierarchical structured surfaces using a single-step deep reactive ion etch process is proposed. Using this method the complexities generally associated with fabrication of two-tier roughness structures are eliminated...

In this study, the release of gentamicin as a function of time was measured for six different gentamicin-loaded bone cements and related with the surface roughness, porosity and wettability of the cements. Initial release rates varied little between the six bone cements (CMW1, CMW3, CMW Endurance, CMW 2000, Palacos, and Palamed) and ranged from 8.6 to 14.1 microg/cm2/h. The total amounts of gen...

This paper presents a technique for measuring surface roughness (Ra), using photometric stereo method. The method utilizes three or more images of the measured surface from the same view point, taken sequentially under different illumination conditions. The scenes captured by the camera were reconstructed by the least square method to obtain surface normal from surface topography. Three-dimensi...

We theoretically investigate the effect of fabrication-related disorders on subwavelength metal-dielectric-metal plasmonic waveguides. We use a Monte Carlo method to calculate the roughness-induced excess attenuation coefficient with respect to a smooth waveguide. For small roughness height, the excess optical power loss due to disorder is small compared to the material loss in a smooth wavegui...

Micro flexible rolling aims to fabricate submillimeter thick strips with varying thickness profile, where the surface quality of products is mainly determined by initial workpiece surface roughness and subsequent surface asperity flattening process, which is affected by process parameters during rolling. This paper shows a 3D finite element model for flexible rolling of a 250 μm thick workpiece...

This paper presents a technique for measuring surface roughness (Ra), using photometric stereo method. The method utilizes three or more images of the measured surface from the same viewpoint, taken sequentially under different illumination conditions. The scenes captured by the camera were reconstructed by the least square method to obtain surface normal from surface topography. Three-dimensio...

Hydrophobic surfaces with microscale roughness can be rendered ultrahydrophobic by the addition of sub-micron-scale roughness. A simple yet highly effective concept of fabricating hierarchical structured surfaces using a single-step deep reactive ion etch process is proposed. Using this method the complexities generally associated with the fabrication of two-tier roughness structures are elimin...

The overall object of this paper is a systematic study of gaseous flows and thermal transport in twodimensional microand nano-channels using direct simulation Monte Carlo (DSMC) method. In the flow study, a validation of DSMC code was conducted by simulating a continuum flow in microchannel and the results show that the discrepancy of friction coefficient from theoretical prediction is well bel...

A Functional Virtual Prototyping full vehicle model for a tri-axial heavy-duty truck is built, and the nonlinearity of suspension dampers and tires is also considered. With the trajectory of full vehicle gravity center, longitudinal tire force of front wheel, longitudinal acceleration, lateral acceleration, yaw rate and pitch angle as the evaluation indexes of brake property, the influences of ...