An indicator variable was developed that may be used to visualize and detect bi–directionality in wind tunnel strain–gage balance calibration data. First, the calculation of the indicator variable is explained in detail. Then, an empirical criterion is proposed that may be used to decide which load components of a balance have bi–directional behavior. The criterion could be used, for example, t...

With the increasing focus on developing environmentally benign electronic packages, Pb-free alloys have received a great deal of attention. Mishandling of packages during manufacture, assembly or by the user may cause failure of the solder joint. A fundamental understanding of the behavior of Pb-free solders under mechanical shock conditions is lacking. Reliable experimental stress–strain data ...

As technology progresses towards smaller electronic packages, thermomechanical considerations pose a challenge to package designers. One area of difficulty is the ability to predict the fatigue life of the solder connections. To do this one must be able to accurately model the thermo-mechanical performance of the electronic package. As the solder ball size decreases, it becomes difficult to det...

− This article deals with the technical properties of fiber Bragg gratings with regard to their use as the strain-sensitive element in force transducers. Electrical strain gages are widely used in modern, precise force transducers. The electrical strain gage provides both outstanding technical properties and cost-effectiveness. Besides the electrical strain gage, the measurement principle of fi...

This paper describes the development of an innovative carbon nanotube-based non-woven composite sensor that can be tailored for strain sensing properties and potentially offers a reliable and cost-effective sensing option for structural health monitoring (SHM). This novel strain sensor is fabricated using a readily scalable process of coating Carbon nanotubes (CNT) onto a nonwoven carrier fabri...

The VIPTM compressor is a new, high-quality product line from the Dresser-Rand company. It incorporates a valve-in-piston cylinder. This is a unique design which results in higher efficiency and fewer parts. The VIP cylinder design is drastically different from the conventional reciprocating compressor cylinders in that the valve are an integral part of the piston assembly. Finite element analy...

Strain sensing characteristic of carbon nanotubes has been established in the past at nanoscale. In this study, it is shown that the carbon nanotube film sensors, made up of randomly oriented carbon nanotubes, can be used as strain sensors at macro level. A nearly linear trend between the change in voltage, measured using a movable four point probe, and strains, measured using conventional elec...