Traffic Alert and Collision Avoidance System (TCAS): Cockpit Display of Traffic Information (CDTI) investigation. Phase 1: Feasibility study

The possibility of the Threat Alert and Collision Avoidance System (TCAS) traffic sensor and display being used for meaningful Cockpit Display of Traffic Information (CDTI) applications has resulted in the Federal Aviation Administration initiating a project to establish the technical and operational requirements to realize this potential. Phase 1 of the project is presented here. Phase 1 was organized to define specific CDTI applications for the terminal area, to determine what has already been learned about CDTI technology relevant to these applications, and to define the engineering required to supply the remaining TCAS-CDTI technology for capacity benefit realization. The CDTI applications examined have been limited to those appropriate to the final approach and departure phases of flight

Non-point sources and point sources for nutrient and fecal microbe contamination in a typical upland stream: Tates Creek, Madison County, Kentucky

Tates Creek (Madison County, Kentucky) is characterized by an oversupply of nutrients and fecal microbe contamination. Its watershed is dominated by pastureland and immature woodlands with scattered settlements served by septic systems, whereas, 5% of the watershed drains urban areas of Richmond, Kentucky. Creek waters are eutrophic and commonly display levels of Escherichia coli deemed unfit for human contact by United States Environmental Protection Agency standards. Both point and non-point sources existed for stream contaminants. A secondary sewage treatment plant (STP) discharged effluent into the creek until mid-2011 and was a point source for nitrate and phosphate. Pastureland likely contributes dissolved nutrients as well. High ammonium levels occurred sporadically, only sometimes related to plant discharge. After plant shutdown, nutrient levels downstream of the former STP decreased markedly for nitrate and phosphate, but phosphate then became the principal nutrient contaminant, suggesting that nitrogen may be the limiting nutrient within the stream ecosystem. Fecal microbes enter the stream from the sewer system serving the town of Richmond, from cattle farming, and from large developments served by septic systems. We cannot demonstrate any fecal contamination from single residence septic systems. KEY WORDS: stream, water quality, nutrient, ammonium, nitrate, phosphorus, E. col

Project-based science instruction for general-education undergraduates and seventh graders: Practices, proficiency, and pitfalls

For three semesters we conducted a general-education course designed for both undergraduates and seventh-graders in which students investigated contaminant sources and water quality of a local stream. The middle school students attend a local, county school that draws its students from disadvantaged areas of the town of Richmond, Kentucky. Undergraduates were general-education honors students with little predilection toward science. The instructors guided undergraduates through the project, and our honors students then mentored the middle-schoolers in their scientific endeavors. Both sets of students serially investigated the chemical and biological properties of a typical upland stream (Tates Creek, Madison County, Kentucky) impacted by anthropogenic activities as dictated by land use. Students measured water properties such as temperature, conductivity, pH, and oxygen content then sampled stream waters to quantify dissolved nutrient concentration, fecal microbes (Escherichia coli), and stream macroinvertebrates. Nutrients (ammonium, NH4+; nitrate, NO3-; phosphate, PO43-) were measured by colorimetry and E. coli were counted using rapid-assay, IDEXX methods. Students also assessed water quality by classifying and counting macroinvertebrates, and using an established water quality index. Students then summarized their findings with group presentations. Middle-schoolers researched aspects of anthropogenic contamination and stream ecology to present their work as poster projects at an event on the campus of Eastern Kentucky University. Undergraduates gave group presentations in class following the format of an oral presentation at a scientific conference. Courses with embedded projects are challenging from logistical, fiscal, and pedagogical standpoints. Assessment of overall course effectiveness continues, but several aspects emerge. The course seemed most effective for middle-schoolers where teachers saw students actively engage in all aspects of the project, even those students who are generally disinterested in science. Results from undergraduates were mixed. Honors students enjoyed mentoring the seventh graders, but did not fully grasp the impact and nuances of project finding

Mindin\u27 my bus\u27ness

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