Results of the Advanced Space Structures Technology Research Experiments (ASTREX) hardware and control development

Future DOD, NASA, and SDI space systems will be larger than any spacecraft flown before. The economics of placing these Precision Space Systems (PSS) into orbit dictates that they be as low in mass as possible. This stringent weight reduction creates structural flexibility causing severe technical problems when combined with the precise shape and pointing requirements associated with many future PSS missions. Development of new Control Structure Interaction (CSI) technologies which can solve these problems and enable future space missions is being conducted at the Phillips Laboratory, On-Location Site, CA

Development of a Standard Set of Indicators and Metrics for Artificial Intelligence (AI) and Expert System (ES) Software Development Efforts

The purpose of this research was to identify a standard set of indicators and metrics that can be used by program managers to improve their abilities to direct development efforts involving Artificial Intelligence (AI) and Expert Systems (ES). This research addresses two objectives. The first objective is to identify an appropriate set of software indicators and metrics to be used by government program offices for the management of development efforts involving software systems for AI and ES. The second objective is to demonstrate how the resources of the National Software Data and Information Repository (NSDIR) can be used in order to minimize the cost of the research endeavor and to demonstrate the value of the NSDIR as an information resource. A literature search identified a set of indicators and metrics that could be used by managers of AI and ES software development efforts. Data concerning Al and ES software development efforts were collected from the NSDIR. Unfortunately, substantiated conclusions regarding the value of the data in regards to AI and ES development efforts were unobtainable. The study did produce a recommended set of indicators and metrics that could serve as a feasible starting point for managers to use in the tailoring process for selecting indicators and metrics for AI and ES software development efforts

Modeling, system identification, and control of ASTREX

The modeling, system identification and controller design aspects of the ASTREX precision space structure are presented in this work. Modeling of ASTREX is performed using NASTRAN, TREETOPS and I-DEAS. The models generated range from simple linear time-invariant models to nonlinear models used for large angle simulations. Identification in both the time and frequency domains are presented. The experimental set up and the results from the identification experiments are included. Finally, controller design for ASTREX is presented. Simulation results using this optimal controller demonstrate the controller performance. Finally the future directions and plans for the facility are addressed

Empiricism, theoretical concepts and the development of the British golf club before 1914

Golf took the concept of the club from traditional voluntary organizations along with the ideas of committee structures, mechanisms for ensuring exclusivity and a place, both geographically and socially, for communal conviviality. It became one of the fastest growing recreational activities of late nineteenth and early twentieth-century Britain and the first participant sport to expend and invest large sums of money. By means of a model constructed around the development of the British golf club before 1914, this paper offers a new approach to examining the history of associativity in sport. It uses five concepts of capital – physical, financial, cultural, social, and human – and argues that their formation in the context of club development should not be explored in isolation of each other