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Sang Choi

Publications and source records attributed to Sang Choi.

5 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2022

Approaches To Humans-Mars Both Safe and Affordable

The fundamental differences regarding the Moon vs. Mars for humans include far longer missions and greater resources required for Mars. In humans-Mars planning, thus far the extant technologies and approaches have not enabled missions which are both fully safe/healthy for humans and affordable. Cost reductions are required to afford health and safety and to reduce their costs. This report suggests and examines a wide spectrum of approaches to improve the affordability of humans-Mars approaches to ensure human safety and health during long distance space exploration and pioneering-on-the-way to colonization with humans-Mars as the exemplar

Dennis M. Bushnell↗
NASA NTRSDate not supplied

TPSAS-NF1676L-16388-DND

The 60° rotated twin defect on {111} planes is one of the most common crystal structure defects in the cubic semiconductors. This defect has a sigma-3 grain boundary commonly called the sigma-3 twin defect on {111} plane. Sigma-3 twin defects are also frequently found in the group IV semiconductors (Si, Ge, C) in a diamond structure and other cubic zinc blende III-V and II-VI compound semiconductors such as GaP, InP, InGaAs, CdTd and ZnSe.

Yeonjoon Park↗