A Microgravity investigation was conducted on an excavated foundation located in the Technical University of Tehran. The aim was the detection of subsurface cavities or other anomalous conditions that threaten the stability of the foundation. The survey consists of 420 gravity stations. The positive coarse grain alluvium saturated by surplus water and negative cavity anomalies have been detected based on the Bouguer and second vertical derivative maps. The depth of the sources has also been determined. To confirm the results an inversion 2D-modelling is also applied to residual anomalies. Some of the shallow accessible anomalies have been confirmed in the field by excavation.

In this paper, the fluid characteristics of pitching sloshing under Microgravity condition are investigated. A numerical method by solving the Navier-Stokes equations to study three-dimensional (3-D) nonlinear liquid sloshing is developed with OpenFOAM, a Computational Fluid Dynamics (CFD) tool. The computational method is validated against existing experimental data in rectangular tank under ordinary gravitational field. However under low gravity conditions, the sloshing liquid shows seemingly chaotic behavior and a considerable volume of liquid attaches on the sidewall due to the effect of surface tension, which is verified in simulation experiment. Besides, the nonlinear liquid behaviors in hemi-spherically bottom tank are firstly studied in this paper. It is found that the wave evolution becomes divergent with the decrease of gravitational acceleration. The natural frequency reaches a constant magnitude quickly with the increase of liquid height and then increases again until the filling level exceeds 70%. Meanwhile, the liquid dynamics of forced pitching sloshing under resonant and off-resonant condition are demonstrated respectively. The numerical techniques for 3-D simulation are hopeful to provide valuable guidance for efficient liquid management in space.

Cosmic rays in the atmosphere can cause leukemia and other diseases in the astronauts. Changing in Microgravity weight make some unwanted effects on cells of the immune system and hematopoiesis. However, the activity of the body organisms is random in different people, but it can be simulate by special models. There are many different models of hematopoiesis that are simulated the effect of Microgravity in the bone marrow. In this study, a self-developed code is used for investigation of absorbed dose effects on declining health of the tissue, blood and lymph, due to cosmic rays in space. The simulation was implemented for different kinds of input dose to body with different time duration. This phenomenon is surveyed for two cases: with considering to effect of production and reproduction of the cells and Microgravity and without considering them. The results show effect of production and reproduction of the cell and Microgravity can be improve or damage of normal cell about centesimal percent. Also, it can be initiate the anemia and the leukemia on the human at long time.

In this work, the rising of a single bubble in a quiescent liquid under Microgravity condition was simulated. In addition to general studies of Microgravity effects, the initiation of hydrodynamic convection, solely due to the variations of interface curvature (surface tension force) and thus the generation of shearing forces at the interfaces was also studied. Then, the variation of surface tension due to the temperature gradient (Marangoni convection), which can initiate the onset of convection even in the absence of buoyancy, was studied. The related unsteady incompressible full Navier-Stokes equations were solved using a finite difference method with a structured staggered grid. The interface was tracked explicitly by connected marker points via a hybrid front capturing and tracking method. A one field approximation was used where one set of governing equations is only solved in the entire domain and different phases are treated as one fluid with variable physical properties, while the interfacial effects are accounted for by adding appropriate source terms to the governing equations. Also, a Multi-grid technique, in the context of the projection method, improved convergences and computational stiffness. The results show that the bubble moves in a straight path under Microgravity condition, compared to the zigzag motion of bubbles in the presence of gravity. Also, in the absence of gravity, the variation of surface tension force due to interface curvature or temperature gradient can still cause the upward motion of the bubble. This phenomenon was explicitly shown in the results of this paper.

The risk of leukemia and other radiation oriented diseases for astronauts increases with exposure to cosmic radiation. During the space missions, the blood and immune system change and the bones are affected by osteoporosis. In this research, a model, based on the human blood system, is presented for the study of the Microgravity and the space radiation effects on the blood cells. This model is used to study the changes in the blood platelets. The reduced platelets are simulated by the Microgravity effect and space radiation. Then, the obtained results were compared with actual data. The results show that the platelets concentration is changed and the platelets are reduced by the Microgravity and space radiation. The platelets have been reduced about 1.6% due to space radiation and Microgravity effects and 1.3% for only the space radiation that it in agreement with the actual data. Therefore, for long space mission, it is necessary to consider reduced platelets, beside the other medical consideration.

It is henceforth a commonplace; the science-fiction would be a refractory genre by nature against the definitive assimilation to the literary mainstream. We can say that the usual thematic of the genre, to which is added the irresistible propensity to prospect the future in all its forms, immunizes the SF against the “academic confinement” to the benefit of other forms of confinement. Indeed, the SF belongs to the great family of the paraliterature where the more or less listed subgenres are waiting to receive a likely definition. Popular genre which relies on a remarkable poetic, the SF is an open place to the imagination, to the verbal and the figurative creativity. It owns itself its subgenres, among other things, the space opera which was, in a way, the original matrix of the speculative fiction and of its contemporary imitators. The Sternberg’s work did not have a special vocation to feed the already rich world of the science-fiction. It constitutes however a new step liable to bring a touch of self-reflexivity, we will notice that, to the history of this genre. French: “Le Navigateur” de Jacques Sternberg ou la phylogenese parodiee du space opera C’est dorenavant un lieu commun, la science-fiction serait un genre par nature refractaire a l’assimilation definitive au mainstream litteraire. Nous dirons que les thematiques habituelles du genre, auxquelles viennent se meler l’irresistible propension a prospecter l’avenir sous toutes ses formes, immunisent la SF contre “l’enfermement academique” au profit d’un enfermement d’un autre genre. En effet, celle-ci appartient, comme on le sait, a la grande famille de la paralitterature ou se cotoient les sous-genres plus ou moins repertories en attente de recevoir un semblant de definition. Genre populaire s’appuyant sur une poetique singuliere, la SF est un lieu ouvert a l’imagination, a la creativite verbale et figurative. Elle possede elle-meme ses sous-genres, entre autres, le space opera qui fut en quelque sorte la matrice originelle de la fiction speculative et de ses emules contemporaines. L’oeuvre sternbergienne n’eut guere pour vocation de nourrir le repertoire deja riche de la science-fiction. Elle constitue neanmoins une etape non repertoriee susceptible d’apporter, nous le constaterons, une touche d’auto-reflexivite a l’histoire du genre.Keywords: Jacques Sternberg, Nouvelle, Science-Fiction, space Opera, Aventure, Fiction Speculative