منابع مشابه
Ptah: Validation Driven Software Development
We describe the motivation and concepts of a validation driven software development process (PTAH). It extends the use-case driven approach defined by Jacobsen et al. (1992) and the unified process described by Jacobsen et al. (1999) by actively integrating end users into the requirements specification and its direct evaluation. Our experience in software projects clearly shows that even graphi...
متن کاملDeep Impact : Excavating Comet Tempel
Introduction: On 4 July 2005, Deep Impact delivered 19 GJoules of kinetic energy to the nucleus of comet Tempel 1, taking numerous images and spectra of the comet before, during, and after the impact. The preliminary analysis of the data has already lead to significant, new understanding of cometary properties and behavior [1] and this talk will summarize the present state of our understanding ...
متن کاملDeep Impact: excavating comet Tempel 1.
Deep Impact collided with comet Tempel 1, excavating a crater controlled by gravity. The comet's outer layer is composed of 1- to 100-micrometer fine particles with negligible strength (<65 pascals). Local gravitational field and average nucleus density (600 kilograms per cubic meter) are estimated from ejecta fallback. Initial ejecta were hot (>1000 kelvins). A large increase in organic materi...
متن کاملA ' Hearn , Deep Impact : Excavating Comet Tempel
http://www.sciencemag.org/cgi/content/full/310/5746/258 version of this article at: including high-resolution figures, can be found in the online Updated information and services, http://www.sciencemag.org/cgi/content/full/1118923/DC1 can be found at: Supporting Online Material found at: can be related to this article A list of selected additional articles on the Science Web sites http://www.sc...
متن کاملThe Coma of Comet 9p/tempel 1
As comet 9P/Tempel 1 approaches the Sun in 2004–2005, a temporary atmosphere, or “coma,” will form, composed of molecules and dust expelled from the nucleus as its component icy volatiles sublimate. Driven mainly by water ice sublimation at surface temperatures T > 200 K, this coma is a gravitationally unbound atmosphere in free adiabatic expansion. Near the nucleus (≤102 km), it is in collisio...
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ژورنال
عنوان ژورنال: Journal of Association of Arab Universities for Tourism and Hospitality
سال: 2018
ISSN: 1687-1863
DOI: 10.21608/jaauth.2018.47947