Improved Ballistic Wind Prediction Using Projectile Tracking Data

The United States Air Force AC-130 gunships have been in operation since the Vietnam War and have seen frequent use during recent conflicts. They are able to employ gun weapon systems from above a target in a way that maximizes possible time on target. When firing, the gun operators must deal with miss distances caused by winds acting on the projectile in flight. Operators currently perform a “tweak” to predict a ballistic wind affecting fired rounds which is then used in the fire-control to correct for the real winds and bring shots onto target. This correction, a single-point wind prediction, is made using only the initial state of the gun and aircraft and the final impact location. This thesis explores the possibility of using a round tracking sensor to track a projectile as it falls and produce a multipoint ballistic wind which would be better at correcting for true winds than a single-point ballistic wind. An algorithm for a multipoint wind prediction method is described and simulation are run using it and a single-point prediction method against measured wind profiles. The results of the single-point and multipoint ballistic winds are compared to the measured winds to test for a goodness of fit. The results are also tested for stability that when used the ballistic wind remains valid even if the aircraft and gun change state from the initial state when the ballistic wind was predicted. The results show that a multipoint ballistic wind that is a better fit and more stable ballistic wind than a single-point ballistic wind is possible using the algorithm presented. Also, the multipoint ballistic wind can be produced with very few data points along the trajectory of the projectile

Alien Registration- Kenney, William A. (Anson, Somerset County)

https://digitalmaine.com/alien_docs/8972/thumbnail.jp

The modern reputation of Samuel Johnson

Thesis (Ph.D.)--Boston UniversityMore attention is now being paid Samuel Johnson than at any time since the years immediately following his death. The object of this dissertation is to clarify his reputation as man and as writer through systematizaton of the majority of the almost two thousand studies written since 1887, the year that George Birkbeck Hill published his edition of Boswell's Life. The vitality of Johnson's reputation can be seen in many ways. The latter half of the eighteenth century has been called "The Age of Johnson." Critics have traditionally considered him a literary dictator, although it is now known that England has never had a man who could claim such absolute power over her letters. Homage has been paid him through the founding of clubs, the making of pilgrimages to sites associated with him, and the collecting of souvenirs. He has been compared and contrasted with diverse figures from history and fiction. Apocryphal stories have been told about him, and he has often been the subject of imaginary conversations, plays, and novels. Johnson has been made symbolic of the eighteenth century by many who think of the period as a time of peace and contentment. [TRUNCATED

Historic low‐level phosphorus enrichment in the Great Lakes inferred from biogenic silica accumulation in sediments

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109982/1/lno2006511part20728.pd

Generic Spacecraft Model for Real-Time Simulation

Generic Spacecraft is the name of an evolving library of software that provides for simulation of a generic spacecraft that can orbit the Earth and land on the Moon (and, eventually, on Mars). This library is incorporated into the Langley Standard Realtime Simulation in C++ (LaSRS++) software framework. The generic-spacecraft simulation serves as a test bed for modeling spacecraft dynamics, propulsion, control systems, guidance, and displays. The Generic Spacecraft library supplements the LaSRS++ framework with an interface that facilitates the connection of new models into the LaSRS++ simulation by eliminating what would otherwise be the necessity of writing additional C++ classes to record data from the models and code to display values on graphical user interfaces (GUIs): The library includes routines for integrating new models into the LaSRS++ framework, identifying model inputs and outputs with full descriptions and units identified, recording data, and automatically generating graphical user interfaces (GUIs). The library is designed to be used in a manner similar to that of LaSRS++ software components for simulating vehicles other than the generic spacecraft. The user specifies (1) a spacecraft and individual models to be constructed and (2) connections between individual model inputs and outputs