Evasive maneuver subsequent to CSM/LM ejection from the S-4B in earth orbit - Project Apollo

Apollo 9 evasive maneuver after command service module/lunar module ejection from Saturn S-4B stage in earth orbi

Playing it safe: developing young children’s understanding of digital networks

Teaching tech through play-based learning can help children to start exploring the digital environment and develop their skills and competence from a very young age. For www.parenting.digital, Dan Donahoo, Senior Advisor at the Alannah & Madeline Foundation, talks about the development of the programme Playing IT Safe – a tool which aims to help parents, carers and educators teach pre-school children how to stay safe online through activities and play. It encourages and supports parents to model safe practices by co-viewing and co-playing with their children and helps educators to scaffold children’s learning by adapting the activities to children’s needs. So how is Playing IT Safe teaching children the skills they need for a digital future and what is the right age to start educating children about digital technology use

NASA/DOD earth orbit shuttle traffic models based on end to end loading of payloads

An analysis of the spacecraft configurations and space missions for the Earth Orbit Shuttle traffic model based on an end-to-end loading of payloads is presented. Two possible reusable tugs are considered. The space missions are described with respect to the following: (1) number of earth orbit shuttle flights by inclination, (2) total payloads to orbit, (3) energy stages required, and (4) characteristics of reusable tug

NASA/DOD earth orbit shuttle traffic models based on side by side loading of payloads

An analysis of the spacecraft configurations and space missions for the Earth Orbit Shuttle traffic model based on side-by-side loading of payloads is presented. The reusable tugs to be employed for the mission are examined. The space missions are described with respect to the following: (1) number of Earth Orbit Shuttle flights by inclination, (2) total payloads to orbit, (3) energy states required, and (4) characteristics of reusable tug

An Ongoing Treasure Hunt: One Library’s Practical Experiences Documenting Post-Cancellation Perpetual Access

Albertsons Library embarked on a practical effort this past year to document post-cancellation perpetual access for those electronic journal titles that had been or were part of large package purchases. Documenting entitled content was challenging and hampered by limits to accounting records maintained at the library and university; a change in the library’s integrated library system (ILS); limited or incomplete access to third-party subscription agent order and payment records; and changes or the demise of consortia. Decisions were made to work with the known more recent electronic journal content purchased, and to work backwards from there. Procedures for creating standardized perpetual access documentation by title was devised for use in the ILS cataloging module as well as the library’s electronic resource management system. By creating a method for documenting perpetual access, institutions are able to support claims for access purchased by the library, even as content shifts from one publisher to another

Contamination of spacecraft by recontact of dumped liquids

Liquids partially freeze when dumped from spacecraft producing particles which are released into free space at various velocities. Recontact of these particles with the spacecraft is possible for specific particle sizes and velocities and, therefore, can become contamination for experiments within the spacecraft or released experiments as a result of waste and potable water dumped from Space Shuttle. An examination of dump characteristics was conducted on STS-29 using both on-board video records and ground based measurements. A preliminary analysis of data from this flight indicates particle velocities are in the range of 30 to 75 ft/sec and recontact is possible for limited particle sizes

Analysis of Performance of Dynamic Multicast Routing Algorithms

In this paper, three new dynamic multicast routing algorithms based on the greedy tree technique are proposed; Source Optimised Tree, Topology Based Tree and Minimum Diameter Tree. A simulation analysis is presented showing various performance aspects of the algorithms, in which a comparison is made with the greedy and core based tree techniques. The effects of the tree source location on dynamic membership change are also examined. The simulations demonstrate that the Source Optimised Tree algorithm achieves a significant improvement in terms of delay and link usage when compared to the Core Based Tree, and greedy algorithm

Determination of Boron in Organoboron Compounds

Analytical Chemistr