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S. Russell

Publications and source records attributed to S. Russell.

Progress of chemical characterization of asteroid Ryugu samples

It is believed that meteorites come from asteroids. Samples of asteroid (25143) Itokawa returned by the JAXA Hayabusa mission revealed that S-type asteroids are composed of materials consistent with the ordinary chondrite class[1,2]. The JAXA Hayabusa 2 [3]spacecraft launched on December 3rd, 2014 towards an asteroid (162173) Ryuguto clarify relationships between C-type asteroids and the carbonaceous chondrite class. Remote sensing observations from Hayabusa 2 show that (1) the albedo of Ryugu is darker than those of every known meteorite class[4, 5], (2) an absorption band at 2.72 μm indicates that phyllosilicates are ubiquitous on Ryugu [5],(3) the strength and shape of the absorption band feature suggests that Ryugu materials experienced heating above 300 °C[6], and (4) thermal inertia suggests that Ryugu materials are more porous than every known carbonaceous chondrite[7]. These results suggest that carbonaceous chondrite class materials are plausible for Ryugu materials, but no known carbonaceous chondrite completely matches the results obtained from Ryugu. *Complete abstract available in attached document

Lan Anh Ngoc Nguyen↗

The Emphasis of Design Patterns in Expressing Expert Knowledge From A Technical Solution – A Framework for Continued Research

Digital Engineering is a transformative strategy that leverages an integrated model-based approach to improve communication, decision making, design understanding, and acquisition efficiency of system development. As modern systems are derived from pre-existing systems, harvesting expert knowledge from proven systems in a useful, model-based way will reduce the experiential learning and cognition required for new system development, contributing to a Digital Engineering transformation. Motivated by performance gains observed during a multi-year, sequential development activity, this survey reviews knowledge, architecture, and pattern literature to establish a framework for research of architectural methods for expert knowledge identification and description using Model Based System Engineering. The multi-year sequential development activity is offered as the experimental system of interest for this research. This work aims to enable a digital engineering strategy that improves concept phase decision making, accelerates knowledge acquisition from lessons learned repositories, and eases the burden of generational knowledge loss.

Lithium Ion↗