24 research outputs found
Deep Space Systems Technology Program Future Deliveries
NASA is in a period of frequent launches of low cost deep space missions with challenging performance needs. The modest budgets of these missions make it impossible for each to develop its own technology, therefore, efficient and effective development and insertion of technology for these missions must be approached at a higher level than has been done in the past. The Deep Space Systems Technology Program (DSST), often referred to as X2000, has been formed to address this need. The program is divided into a series of "Deliveries" that develop and demonstrate a set of spacecraft system capabilities with broad applicability for use by multiple missions. The First Delivery Project, to be completed in 2001, will provide a one MRAD-tolerant flight computer, power switching electronics, efficient radioisotope power source, and a transponder with services at 8.4 GHz and 32 GHz bands. Plans call for a Second Delivery in late 2003 to enable complete deep space systems in the 10 to 50 kg class, and a Third Delivery built around Systems on a Chip (extreme levels of electronic and microsystems integration) around 2006. Formulation of Future Deliveries (past the First Delivery) is ongoing and includes plans for such developments as highly miniaturized digital/analog/power electronics, optical communications, multifunctional structures, miniature lightweight propulsion, advanced thermal control techniques, highly efficient radioisotope power sources, and a unified flight ground software architecture to support the needs of future highly intelligent space systems. All developments are targeted at broad applicability and reuse, and will be commercialized within the US
Episodic-like memory in wild free-living blue tits and great tits
Episodic-like memory in non-human animals represents the behavioral characteristics of human episodic memory—the ability to mentally travel backward in time to “re-live” past experiences. A focus on traditional model species of episodic-like memory may overlook taxa possessing this cognitive ability and consequently its evolution across species. Experiments conducted in the wild have the potential to broaden the scope of episodic-like memory research under the natural conditions in which they evolved. We combine two distinct yet complementary episodic-like memory tasks (the what-where-when memory and incidental encoding paradigms), each targeting a different aspect of human episodic memory, namely the content (what-where-when) and process (incidental encoding), to comprehensively test the memory abilities of wild, free-living, non-caching blue tits (Cyanistes caeruleus) and great tits (Parus major). Automated feeders with custom-built programs allowed for experimental manipulation of spatiotemporal experiences on an individual-level basis. In the what-where-when memory experiment, after learning individualized temporal feeder rules, the birds demonstrated their ability to recall the “what” (food type), “where” (feeder location), and “when” (time since their initial visit of the day) of previous foraging experiences. In the incidental encoding experiment, the birds showed that they were able to encode and recall incidental spatial information regarding previous foraging experiences (“where” test), and juveniles, but not adults, were also able to recall incidentally encoded visual information (“which” test). Consequently, this study presents multiple lines of converging evidence for episodic-like memory in a wild population of generalist foragers, suggesting that episodic-like memory may be more taxonomically widespread than previously assumed
Does gender determine journalists' professional views? A reassessment based on cross-national evidence
Research into journalism and gender to date has found somewhat contradictory evidence as to the ways in which women and men practice journalism. While some scholars claim that women have inherently different concepts and practices of journalism and that this has led to a feminization of journalism, others have found little evidence to suggest that men and women differ significantly in terms of their role conceptions. While numerous studies have been conducted into this issue around the world, few have taken a truly comparative approach. This paper presents results from a large-scale comparative survey into gender differences in journalists’ professional views in 18 diverse countries around the world. Results suggest that women and men do not differ in any meaningful ways in their role conceptions on neither the individual level, in newsrooms dominated by women, nor in socio-cultural contexts where women have achieved a certain level of empowerment