Time maintenance of user clocks via the tracking and data relay satellite system

A system is described which uses the Tracking and Data Relay Satellite System (TDRSS) itself to compare the user satellite clock with a clock at the White Sands station that is referenced to Universal Time Coordinated (UTC). No command of the spacecraft by the system is required, and actual on-board clock corrections are made by the spacecraft control center at its discretion. Computer models were constructed using basic orbital parameters for user and TDRS satellites. With only first-order corrections and simple averaging techniques for constant clock rates, error measurement precision of better than one microsecond was obtained. More sophisticated computations should allow considerable improvement over this

Potential-vorticity inversion and the wave-turbulence jigsaw: some recent clarifications

Two key ideas stand out as crucial to understanding atmosphere-ocean dynamics, and the dynamics of other planets including the gas giants. The first key idea is the invertibility principle for potential vorticity (PV). Without it, one can hardly give a coherent account of even so important and elementary a process as Rossby-wave propagation, going beyond the simplest textbook cases. Still less can one fully understand nonlinear processes like the self-sharpening or narrowing of jets – the once-mysterious "negative viscosity" phenomenon. The second key idea, also crucial to understanding jets, might be summarized in the phrase "there is no such thing as turbulence without waves", meaning Rossby waves especially. Without this idea one cannot begin to make sense of, for instance, momentum budgets and eddy momentum transports in complex large-scale flows. Like the invertibility principle the idea has long been recognized, or at least adumbrated. However, it is worth articulating explicitly if only because it can be forgotten when, in the usual way, we speak of "turbulence" and "turbulence theory" as if they were autonomous concepts. In many cases of interest, such as the well-studied terrestrial stratosphere, reality is more accurately described as a highly inhomogeneous "wave-turbulence jigsaw puzzle" in which wavelike and turbulent regions fit together and crucially affect each other's evolution. This modifies, for instance, formulae for the Rhines scale interpreted as indicating the comparable importance of wavelike and turbulent dynamics. Also, weakly inhomogeneous turbulence theory is altogether inapplicable. For instance there is no scale separation. Eddy scales are not much smaller than the sizes of the individual turbulent regions in the jigsaw. Here I review some recent progress in clarifying these ideas and their implications

Fluorine gas as a cleaning agent for Apollo bulk-sample containers

A technique has been developed for cleaning Apollo bulk sample containers using fluorine gas as the cleaning agent

A Uganda Case Study: Using Non-Formal Education to Increase the Quality of Education

Education is a universal right because it determines a person’s future. Education is becoming more important as the youth population continues to increase exponentially in sub-Saharan Africa. Current research shows that the international community needs to focus on the education sector to improve development. One type of education proven to aid in low-resource countries is non-formal education because it is flexible enough to fit the needs of students in communities. Youth empowerment has become a popular method for non-formal education because of its ability to transform a community. Uganda is a developing country with one of the largest youth populations in the world and education is lagging to improve quality of life. The project in this study will discover if non-formal education can become a solution for increasing the quality of education at Musana Nursery and Primary School by having a flexible afterschool program curriculum catered to students’ needs as they continue their education pathway

The Principalship - A Look to the Past and Projections for the Future

Over the years, the principalship has become increasingly specialized with diverse organizational arrangements

Alien Registration- Mcintyre, Marie E. (Lincoln, Penobscot County)

https://digitalmaine.com/alien_docs/7368/thumbnail.jp

Book Review

Reviewing Alfred Avins, The Law of AWOL, Oceana Publications, 195