Guidance for an aeroassisted orbital transfer vehicle

The use of atmospheric drag for slowing satellite in high energy, high apogee orbits to a lower energy, lower apogee orbit about the Earth is investigated. The high energy orbit is assumed to intercept the Earth's atmosphere. Guidance for the atmospheric phase of the trajectory may be done using the aerodynamic forces generated by the passage through the atmosphere. This research was concerned with the investigation of several methods of guidance during the atmospheric phase to cause a significant reduction in the final velocity as the vehicle leaves the atmosphere. In addition, the velocity direction was controlled to exit to a desired target orbit. Lastly excess aerodynamic lift was used to effect a plane change between the entry orbit plane and the exit orbit plane to achieve a desired orbit plane. The guidance methods were applied to a 3 degree-of-freedom simulation which included an oblate Earth gravity model and a rotating atmosphere. Simulation results were compared on the basis of speed of computation of the guidance parameters and amount of added velocity necessary to achieve the desired orbit

Seasonal Occurrence of Pine Root Collar Weevil, \u3ci\u3eHylobius Radicis\u3c/i\u3e (Coleoptera: Curculionidae), in Red Pine Stands Undergoing Decline

A trapping scheme was devised for sampling the pine root collar weevil, Hylobius radicis, in mature red pine plantations in Wisconsin. Adult weevils were trapped throughout the 1986 field season, and the method appears sensitive enough to discern temporal and spatial trends. The number of weevils caught was higher in stands symptomatic of the general condition currently labelled Red Pine Decline and Mortality. In some stands there was a strong tendency for trap catches to be particularly high near certain trees. Seasonal trends and sex ratios were compared with published reports of H. radicis activity in Michigan

Mountain Men on Film

Excerpt: The mountain man of American folklore and history is a man between cultures. Like Janus, the doorkeeper god of the Romans, he is bifrontal, looking back at European, white civilization, and forward toward Indian civilization and culture

From the Iron Horse to Hell on Wheels: The Transcontinental Railroad in the Western

Excerpt: I\u27m crazy about trains! says Doc Holliday (Jason Robards) to his friend Wyatt Earp (James Garner) in Hour of the Gun (Sturges Ch. 6), explaining why he\u27s waiting on the Contention train. Of course he\u27s really there to help Earp get his revenge on Ike Clanton (Robert Ryan) - but then we never quite know with Doc Holliday

Exploring the Influence of Collaborative Capabilities on Focal Firm Product Outcomes ;the Mediating Role of Supplier Capabilities

As markets become more turbulent, dynamic, and competitive, and as customers become more sophisticated and demanding, the scope of capabilities and resources needed to meet customer needs, wants, and desires are less likely to be found in any one firm. Instead, firms must develop strong collaborative capabilities. Though the benefits of interfirm collaboration for focal firms (the firms responsible for the final offering) and suppliers are reasonably well understood, effectiveness and efficiency in collaboration remain elusive for many firms. It is likely that the collaborative capabilities of both focal firms and key suppliers contribute to effective collaboration, and that the collaborative capabilities of focal firms may influence the collaborative capabilities of suppliers, which in turn influence product-market outcomes. This dissertation proposes an integrative model drawing on three prominent streams in collaboration and supply chain research. In the proposed model, supplier collaborative capabilities mediate the association between focal-firm collaborative capabilities and operational product-market outcomes (closeness of the final offering to end-user needs and delivery performance). The model is founded in the knowledge-based and dynamic capabilities views of the firm, and tested empirically with data from a sample of managers from focal firms in industries producing relatively complex final products. Evidence is found of a relationship between focal-firm collaborative capabilities and supplier capabilities, and between supplier capabilities and product-market outcomes. This study contributes to scholarship and practice in interfirm collaboration by testing an integrative model drawn from three prominent streams of collaboration and supply chain research, by clarifying the dimensions of the collaborative communications construct and investigating its relationship with operational outcomes, by investigating the mediating role of supplier capabilities on product-market outcomes, and by extendi

Apaches and Comanches on Screen

Excerpt: A generally accurate appraisal of Western films might claim that Indians as hostiles are grouped into one undifferentiated mass. Popular hostile groups include the Sioux (without much differentiation between tribes or bands, the Apaches, and the Comanches)