385 research outputs found
MISSISSIPPI PERIOD OCCUPATIONAL AND POLITICAL HISTORY OF THE MIDDLE SAVANNAH RIVER VALLEY
Research focusing on the political economy of Mississippian mound centers in the middle Savannah River valley has prompted a reevaluation of current interpretations regarding societal complexity. I conclude the clearest expression of classic Mississippian riverine-adaptation is evident at centers immediately below the Fall Line with their political ties to chiefdom centers in the Piedmont, and especially Etowah. By contrast, those centers on the interior Coastal Plain were politically autonomous with minimal signatures in social ranking. The scale of appropriated labor and resulting level of surplus production, necessitated by upland settlement on the Aiken Plateau, fostered social contradictions making communally-oriented and decentralized societies more sustainable than hierarchical forms
Lunar ISRU Energy Storage and Electricity Generation
The survival of the astronauts and their equipment is the priority for any long-term exploration mission
to the Moon. The provision of energy during the long lunar nights is a critical part of these missions.
Several approaches have recently been considered to store and provide energy on the Moon by means of
ISRU (In-Situ Resource Utilisation). We present a review of the energy requirements for a long mission
scenario, and a trade-off analysis of the potentially suitable technologies for an ISRU-based system able
to store heat and generate electricity. The most promising combinations of technologies are presented.Peer ReviewedPostprint (published version
Simulation of a full ISRU-based system for energy storage and electricity generation on the Moon
The survival of the crew and assets during the lunar night is one of the biggest challenges in the exploration of the Moon. The storage and supply of energy are key elements for the success of a mission. We present numerical simulations of a system based on ISRU that stores solar energy during the day and generates electricity during the night. We carried out analyses of each subsystem as well as simulations of the full system. Estimates of the performance of the system in terms of power output and mass of the system are presented.This work was financially supported by the European Space Agency (ESA) through contract 4000124000/18/NL/AF.Peer ReviewedPostprint (published version
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