Dynamic Equivalence of Control Systems and Infinite Permutation Matrices

To each dynamic equivalence of two control systems is associated an infinite permutation matrix. We investigate how such matrices are related to the existence of dynamic equivalences

Development of Low Density Flexible Carbon Phenolic Ablators

Phenolic Impregnated Carbon Ablator (PICA) was the enabling TPS material for the Stardust mission where it was used as a single piece heatshield. PICA has the advantages of low density (0.27g/cm3) coupled with efficient ablative capability at high heat fluxes. Under the Orion program, PICA was also shown to be capable of both ISS and lunar return missions however some unresolved issues remain for its application in a tiled configuration for the Orion-specific design. In particular, the problem of developing an appropriate gap filler resulted in the Orion program selecting AVCOAT as the primary heatshield material over PICA. We are currently looking at alternative architectures to yield flexible and more conformal carbon phenolic materials with comparable densities to PICA that will address some of the design issues faced in the application of a tiled PICA heat shield. These new materials are viable TPS candidates for upcoming NASA missions and as material candidates for private sector Commercial Orbital Transportation Services (COTS). This presentation will discuss flexible alternatives to PICA and include preliminary mechanical and thermal properties as well as arc jet and LHMEL screening test results

Higher Education: Can Debt Beat Savings?

This paper investigates the possible opportunity cost of using standard college savings plans against the advantages of using debt to pay for college. In addition, it presents a practical argument for using debt in place of college savings plans in certain instances. By doing so, investors may not only be able to mitigate the difficulty of saving, but also realize greater financial benefit in the long run

Emmy Temianka Correspondence; (Stackpole)

This collection contains material pertaining to the life, career, and activities of Henri Temianka, violin virtuoso, conductor, music teacher, and author. Materials include correspondence, concert programs and flyers, music scores, photographs, and books.https://digitalcommons.chapman.edu/emmy_temianka_correspondence/1012/thumbnail.jp

All I could to save Our state Black Virginians\u27 participation in the Great War

Historians have started to devote more attention to the drastic changes experienced by African Americans during the First World War. Recent works that have investigated blacks’ participation in the army and activism during the war have focused on broad national movements, without taking into account the regional and local differences found at the state level. Through investigation of the Virginia War History Commission questionnaires, black newspapers, and other sources, a more complex view of black experience in Virginia during the war emerges. The unique political and racial landscape of the state, labeled as the “Virginia Way,” meant blacks faced higher rates of conscription, placement in all black service battalions, and rough conditions at camps both in Virginia and in France. However, these sources also point to a black community that understood the bureaucratic and racist implications of the war, and actively tried to better their situation

Henri Temianka Correspondence; (stackpole)

https://digitalcommons.chapman.edu/temianka_correspondence/2876/thumbnail.jp

Henri Temianka Photographs, Publicity

https://digitalcommons.chapman.edu/paganini_quartet_photos/1018/thumbnail.jp

Henri Temianka Photographs, Publicity

https://digitalcommons.chapman.edu/paganini_quartet_photos/1013/thumbnail.jp