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Bukley, A. P.

Publications and source records attributed to Bukley, A. P..

Analyst-centered models for systems design, analysis, and development

Much has been written about the possible use of Expert Systems (ES) technology for strategic defense system applications, particularly for battle management algorithms and mission planning. It is proposed that ES (or more accurately, Knowledge Based System (KBS)) technology can be used in situations for which no human expert exists, namely to create design and analysis environments that allow an analyst to rapidly pose many different possible problem resolutions in game like fashion and to then work through the solution space in search of the optimal solution. Portions of such an environment exist for expensive AI hardware/software combinations such as the Xerox LOOPS and Intellicorp KEE systems. Efforts are discussed to build an analyst centered model (ACM) using an ES programming environment, ExperOPS5 for a simple missile system tradeoff study. By analyst centered, it is meant that the focus of learning is for the benefit of the analyst, not the model. The model's environment allows the analyst to pose a variety of what if questions without resorting to programming changes. Although not an ES per se, the ACM would allow for a design and analysis environment that is much superior to that of current technologies.

Bukley, A. P.

Effects of bearing deadbands on bearing loads and rotor stability

The Jeffcott model of a turbopump which was modified by adding deadband (clearance) effects along with fluid seal forces are currently understood. Equations of motion for the model were written in polar coordinates, and a constant side force was added to the model to account for the likely misalignment between bearings and seals. The force models and system equations of motion are described as well as limit cycle, and stability analyses. Studies of systems with rotor imbalance and with or without side effects were studied for three types of motion. Results show that: (1) deadband does not affect stability-in-the-large; (2) stability-in-the small is enhanced by deadband and side force; (3) bearings loads are highest for motion with synchronous or nonsynchronous periodic enclosing origin; (4) side force acting in concert with deadband effects may either increase or decrease bearing loads; and (5) bearing loads in a stable pump are determined primarily by rotor imbalance and side forces.

Glaese, J. R.