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Since the end of the Cold War, California's defense complex has scurried to beat swords into plowshares-and now bombers into bridges. With $6 million from the Federal Highway Administration, engineers at the University of California at San Diego (UCSD) plan to erect a 150-meter bridge out of advanced composite materials of the type originally designed for the B-2 bomber. The four-lane span, to arc over Interstate 5 near campus, will be the longest bridge ever built from composite materials, says Gilbert Hegemier, a project leader at UCSD. The 3-year project will also serve, he hopes, as the "technical driver for what we think is a new industry." Polymeric matrix composites, made by impregnating fabrics woven from high-strength carbon threads with an epoxy such as vinyl ester, have a stiffness-to-weight ratio 10 times that of the steel used in construction. That means easier-to-handle materials that could push the limit on long-span bridges and allow speedy erection of buildings.
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Manufacturing in the United States is in trouble. That's bad news not just for the country's economy but for the future of innovation.
This document is part of the “How-To Guide for Most Common Measurements” centralized resource portal. This tutorial provides a detailed guide for measurement and device considerations to take temperature measurements using thermocouples. Get an introduction to thermocouples, which are inexpensive sensing devices widely used with PC-based data acquisition systems. Also review some specific thermocouple examples and learn how thermocouples work and ways to integrate them into a data acquisition measurement system.
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