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NASA’s long range vision for space exploration includes human and robotic missions to extraterrestrial bodies including the moon, asteroids and the martian surface. All feasible extraterrestrial landing sites in the solar system are smaller and have gravitational fields of lesser strength than Earth’s gravity field. Thus, a need exists for evaluating autonomous and human-piloted landing techniques in these reduced-gravity situations. A small-scale, free-flying, reduced-gravity simulation vehicle was designed by a group of senior mechanical engineering students with the help of faculty and graduate student advisors at Utah State University during the 2009-2010 academic year. The design reproduces many of the capabilities of NASA’s 1960s era lunar landing research vehicle using small, inexpensive modern digital avionics instead of the large, expensive analog technology available at that time. The final vehicle design consists of an outer maneuvering platform and an inner gravity offset platform. The two platforms are connected through a set of concentric gimbals which allow them to move in tandem through lateral, vertical, and yawing motions, while remaining independent of each other in rolling and pitching motions. A small radio-controlled jet engine was used on the inner platform to offset a fraction of Earth’s gravity (5/6th for lunar simulations), allowing the outer platform to act as though it is flying in a reduced-gravity environment. Imperative to the stability of the vehicle and fidelity of the simulation, the jet engine must remain in a vertical orientation to not contribute to lateral motions. To this end, a thrust vectoring mechanism was designed and built that, together with a suite of sensors and a closed loop control algorithm, enables precise orientation control of the jet engine. Detailed designs for the thrust vectoring mechanisms and control avionics are presented. The thrust vectoring mechanism uses thin airfoils, mounted directly behind the nozzle, to deflect the engine’s exhaust plume. Both pitch and yaw control can be generated. The thrust vectoring airfoil sections were sized using the two-dimensional airfoil section compressible-flow CFD code, XFOIL, developed at the Massachusetts Institute of Technology. Because of the high exhaust temperatures of the nozzle plume, viscous calculations derived from XFOIL were considered to be inaccurate. XFOIL was run in inviscid flow mode and viscosity adjustments were calculated using a Utah State University-developed compressible skin friction code. A series of ground tests were conducted to demonstrate the thrust vectoring system’s ability to control the orientation of the jet engine. Detailed test results are presented.

Short range thrusting projectiles are one of the various threats against armored vehicles and helicopters on the battlefield. Developing a countermeasure for this kind of projectiles is very crucial since they are vast in number and easy to operate on the battlefield. A countermeasure may consist of fire point prediction of the projectile and attack the launcher of it, or it may be the impact point prediction of the projectile and apply a hard-kill counter measure on its way to the ally target. For both of the countermeasure concepts, dynamics and parameters of the projectile must be estimated precisely. In this thesis, dynamic models for thrusting and ballistic flight modes of thrusting projectile are obtained. Three different tracking filters are suggested for precise tracking of the projectiles and their estimation performances are compared. These filters are the Extended Kalman Filter (EKF), the Particle Filter (PF) and the Marginalized Particle Filter (MPF).

Construction of semi-automatic equipment DCR 231 means for company Mubea saving money in long-range target. This economy profit rises with time period of the equipment active usage. The equipment is designed as a universal tool of automatic production step for inserting reinforcement tubes into tubular stabilizer bars. Inserting of these tubes into the both stabilizer ends brings higher strength of supported areas. Benefit of stabilizer bar reinforcement only on its ends is a lower mass leads to reduction of the whole axle mass. The equipment in global scale helps to reduce the costs connected with daily vehicle usage.

An ongoing debate concerning Neandertal ecology is whether or not they utilized long range weaponry. The anteroposteriorly expanded cross-section of Neandertal humeri have led some to argue they thrusted their weapons, while the rounder cross-section of Late Upper Paleolithic modern human humeri suggests they threw their weapons. We test the hypothesis that Neandertal humeri were built to resist strains engendered by thrusting rather than throwing using finite element models of one Neandertal, one Early Upper Paleolithic (EUP) human and three recent human humeri, representing a range of cross-sectional shapes and sizes. Electromyography and kinematic data and articulated skeletons were used to determine muscle force magnitudes and directions during three positions of spear throwing and three positions of spear thrusting. Maximum von Mises strains were determined at the 35% and 50% cross-sections of all models. During throwing and thrusting, von Mises strains produced by the Neandertal humerus fell roughly within or below those produced by the modern human humeri. The EUP humerus performed similarly to the Neandertal, but slightly poorer during spear thrusting. This implies the Neandertal and EUP human humeri were just as well adapted at resisting strains during throwing as recent humans and just as well or worse adapted at resisting strains during thrusting as recent humans. We also did not find any correlation between strains and biomechanical metrics used to measure humeral adaptation in throwing and thrusting (retroversion angle, Imax/Imin, J). These results failed to support our hypothesis and suggest they were capable of using long distance weaponry.

Η παρούσα μελέτη παρουσιάζει νέα στοιχεία που αφορούν την τεκτονική και στρωματογραφία του φλύσχη της Νότιας Aιτωλοακαρνανίας και έχει ως στόχο να ερμηνεύσει την τεκτονική εξέλιξη της περιοχής και την κινηματική των επωθήσεων. Γεωλογικά δεδομένα που προέκυψαν από την τεκτονική και στρωματογραφική ανάλυση καθώς και από την ανάλυση αεροφωτογραφιών συνδυάστηκαν με σεισμικές τομές. Οι μεγάλης κλίμακας επωθήσεις της Πίνδου και του Γαβρόβου, που σχηματίζουν ένα προελαύνον προς την προχώρα σύστημα επωθήσεων, δρουν συγχρόνως για μεγάλο διάστημα του Ολιγοκαίνου. Η επώθηση Γαβρόβου χαρακτηρίζεται από σημαντική μετατόπιση (>10 χλμ.), μικρούς ρυθμούς βράχυνσης, και από πολύπλοκη ιστορία προέλασης που περιλαμβάνει και επωθήσεις εκτός ακολουθίας. Επωθήσειςν ΒΒΔ-ΒΔ διεύθυνσης ελέγχουν την τοπογραφία της περιοχής και συνείσφερουν σημαντικά στην πάχυνση του φλύσχη. Η υπέρθεση του φλύσχη ενέτεινε την βύθιση της λεκάνης και την υποβύθιση τμημάτων του φλοιού κάτω από την επώθηση. Η έναρξη της κλαστικής ιζηματογένεσης λαμβάνει χώρα στο Πριαμπόνιο, ενώ το τέλος της προσδιορίστηκε στο Ανώτερο Ολιγόκαινο. Στην Ιόνια λεκάνη η κατώτερη ακολουθία ιζημάτων του φλύσχη αντιστοιχεί σε αποθέσεις εξωτερικού ριπιδίου ενώ η ανώτερη σε αποθέσεις εσωτερικού ριπιδίου-κατωφέρειας. Στην λεκάνη Γαβρόβου επικρατούν κυρίως αποθέσεις εσωτερικού-μέσου ριπιδίου. Τα αποτελέσματα που προκύπτουν από την παρούσα διατριβή υποδηλώνουν ότι το κλασσικό μοντέλο του προελαύνοντος προς την προχώρα συστήματος επωθήσεων, που έχει προταθεί για τις Εξωτερικές Ελληνίδες χρειάζεται σημαντικές τροποποιήσεις. / This study demonstrates new structural and stratigraphic data derived from the syn-orogenic clastic deposits in the Etoloakarnania area, in order to define the structural evolution and the movement history of thrust faults in the area. Geological data derived from structural, stratigraphic analysis and interpretation of air photos combine with data from seismic lines. The crustal-scale Pindos and Gavrovo thrusts,which formed a foreland propagating sequence, acted simultaneously for a long period of Oligocene. The Gavrovo thrust is characterized by significant displacement (>10 km), low shortening rates and a complex propagation history, involving out-of-sequence thrusting. NNW to NW-directed thrusts control the topography of the region and cause a significant thickening of the flysch. The superposition of flysch enhanced further subsidence and underthrusting. The clastic sedimentation began in the Priabonian and lasted till the Late Oligocene. In the Ionian basin the lower part of the clastic sequence corresponds to outer fan deposits, while the upper part corresponds to inner fan-slope deposits. In addition, inner to middle fan associations predominate in the Gavrovo basin. The results of this study show that the classic model of a foreland propagating thrust sequence for the External Hellenides needs significant modifications.

Le bassin de Jaca (Pyrénées espagnoles) est un exemple classique de bassins d’avant pays, où les grandes lignes du remplissage sédimentaire, ainsi que la chronologie des failles ont été très étudiées. Il reste toutefois à mieux comprendre la paléo-hydrologie et l’histoire thermique du bassin, de manière à proposer un modèle de circulation des fluides pendant sa mise en place et sa déformation (Paléocène-Oligocène). Pour ce faire, ce travail propose d’analyser la répartition de la fracturation, d’étudier les conditions de formation des veines syn-tectoniques et de caractériser la maturité de la matière organique sur l’ensemble du paléobassin d’avant-pays de Jaca, des zones internes vers les zones externes.L’analyse pétrographique, géochimique et microthermométrique des veines montre que la grande majorité des fluides minéralisateurs sont à l’équilibre isotopique et thermique avec l’encaissant. Dans le détail, nous avons identifié 2 événements principaux de formation de veines dans la zone interne du bassin (Sierras Interiores), que nous proposons d’associer au fonctionnement des failles majeures dans le socle. Nous suggérons que les fluides circulent le long des niveaux de décollements et sont expulsés sur de courtes distances (< 10 km), au travers des réseaux de fractures, vers le bassin d’avant-pays. Le reste du bassin enregistre principalement des fluides locaux, parfois associés à l’infiltration d’eau météorique. L’analyse des températures d’enfouissement (50°C à 250°C), qui inclut des données de Δ47, montre une organisation N-S relativement homogène depuis les Sierras Interiores (fenêtre à gaz) jusqu’aux Sierras Exteriores (immature), avec des anomalies longitudinales marquées. Les modélisations thermiques 1D sur 9 puits virtuels suggèrent que les températures maximales vers les Sierras Interiores peuvent résulter d’un enfouissement sédimentaire, dont une grande partie est érodée actuellement. Nous proposons que ces parties érodées correspondent à des dépôts tardi-orogéniques conglomératiques déposés à proximité de la zone axiale. Les données suggèrent une répartition non homogène de ces dépôts selon un axe E-W, impliquant des transferts sédimentaires plus complexes qu’habituellement discutés. Au vu de nos résultats et des précédentes études, le modèle paléohydrologique et thermique du bassin de Jaca, et à plus grande échelle, de la chaîne plissée sud-pyrénéenne, est compartimenté à la fois dans l’espace et dans le temps, en lien avec à la propagation latérale et frontale de la déformation, qui contrôle l’ouverture du système. Le modèle paléohydrologique et thermique de la chaîne plissée sud-pyrénéenne constitue donc un potentiel analogue aux chaînes plissées dont le raccourcissement résulte d’une convergence oblique. / The Jaca basin (Spanish Pyrenees) is a classical example of a foreland basin, where the sedimentary filling and the calendar of thrust activation have been extensively studied. It remains to understand the paleohydrology and the thermal history of the basin, so as to provide a fluid flow model related to its formation and deformation (Paleoecene-Oligocene). To do this, this work proposes to analyze the distribution of fracturing, to study the conditions of formation of syn-tectonic veins and to characterize the maturity of organic matter throughout the Jaca foreland basin, from hinterland to external areas.Petrographical, geochemical and microthermometric analysis of veins show that the vast majority of mineralizing fluids are at the isotopic and thermal equilibrium with the host-rock. In detail, we identified two main events of vein precipitation in the inner part of the basin (Sierras Interiores), probably related to major basement thrust activations. We suggest that fluids flow along decollement levels and are expelled over short distances (<10 km), through fracture networks towards the foreland basin. The other part of the basin mainly record local fluids, sometimes associated with the infiltration of meteoric water. Analysis of burial temperatures (50 °C to 250 °C), which includes Δ47 data, shows a relatively homogeneous N-S organization from the Sierras Interiores (gas window) to Sierras Exteriores (immature), with strong longitudinal anomalies. Thermal 1D modelling of 9 virtual wells suggest that the maximum temperatures of Sierras Interiores result from sedimentary accumulation, whose a large amount is now eroded. We propose that this eroded thickness corresponds to late-orogenic conglomeratic deposits near the axial zone. The data suggest an inhomogeneous distribution of the deposits along an E-W axis, involving more complex sedimentary transfers than usually discussed. Given our results and previous studies, the paleohydrological and thermal model of the Jaca basin, and on a larger scale, of the South Pyrenean fold and thrust belt, is compartmentalized both in space and in time, in response to the propagation of and oblique deformational front, which controls the opening of the system. The paleohydrological and thermal model of the South Pyrenean fold and thrust belt is therefore a potential analogue to fold and thrust belt including shortening due to an oblique convergence.