Meeting future workforce needs: FIRST Robotics in Clinton, Massachusetts

School and business partnerships can strengthen the workforce. The vehicle for one such collaboration is FIRST, a national robotics competition that a Massachusetts school district and plastics company Nypro Inc. have participated in since 1992: “the hardest fun ever.”Business and education

Tensile strength of composite sheets with unidirectional stringers and crack-like damage

The damage tolerance characteristics of metal tension panels with riveted and bonded stringers are well known. The stringers arrest unstable cracks and retard propagation of fatigue cracks. Residual strengths and fatigue lives are considerably greater than those of unstiffened or integrally stiffened sheets. The damage tolerance of composite sheets with bonded composite stringers loaded in tension was determined. Cracks in composites do not readily propagate in fatigue, at least not through fibers. Moreover, the residual strength of notched composites is sometimes even increased by fatigue loading. Therefore, the residual strength aspect of damage tolerance, and not fatigue crack propagation, was investigated. About 50 graphite/epoxy composite panels were made with two sheet layups and several stringer configurations. Crack-like slots were cut in the middle of the panels to simulate damage. The panels were instrumented and monotonically loaded in tension to failure. The tests indicate that the composite panels have considerable damage tolerance, much like metal panels. The stringers arrested cracks that ran from the crack-like slots, and the residual strengths were considerably greater than those of unstiffened composite sheets. A stress intensity factor analysis was developed to predict the failing strains of the stiffened panels. Using the analysis, a single design curve was produced for composite sheets with bonded stringers of any configuration

ECONOMICS AND ECOSYSTEM MANAGEMENT: DISCUSSION

Environmental Economics and Policy,

VALUATION OF GROUNDWATER QUALITY CONTINGENT VALUES, PUBLIC POLICY NEEDS, AND DAMAGE FUNCTIONS

In a departure from past contingent valuation research of groundwater quality, this paper estimates a damage function for nitrate exposures based on actual water test results of individual wells. From the perspective of reliability, it is argued that such a full information approach more closely represents the goal of valuation research in this area -to estimate the economic values that people would place on improving water quality if they were actually experiencing contaminated water. The adoption of a damage function approach linking willingness to pay to actual exposures is also more useful to policy makers at the study site because it potentially provides benefit information to a broad range of policy options. Finally, because the damage function is based on objective data that could be obtained from other sources such as local well test programs, such an approach may be desirable from a benefits transfer perspective. Damages, as measured by willingness to pay for protecting individual well supplies within a 10 mg/L NO,-N health standards are estimated to be a concave function of nitrate exposure levels.Resource /Energy Economics and Policy,

Groundwater Flow Demonstration Model Activities for Grades 6-12

This set of activities is designed to use a demonstration model available through the Uath County Cooperative Extension Services or from Project WET. They demonstrate such concepts as aquifers, groundwater flow, water table, the relationship between groundwater and surface water, recharge, and others. A glossary and standards correlations to the Utah Core Curriculum for Science are included. The physical model can be obtained through the Utah County Cooperative Extension Service, the Utah Water Resources Education Program, or for sale from Project WET (Water Education for Teachers). Educational levels: High school, Middle school