Bakgrund Volleyboll är en fysiskt ansträngande idrott som framför allt ställer höga krav på utövarens explosivitet, snabbhet och styrka, där behovet av förmågorna varierar beroende på spelarposition. Med beaktande av den begränsade mängd studier som undersöker olika prestationsförmågor mellan spelarpositioner hos kvinnliga volleybollspelare finns det ett behov av ytterligare studier som undersöker dessa aspekter. Syfte Undersökningens primära syfte var att statistiskt analysera fysiska prestationsförmågor under säsong hos kvinnliga volleybollspelare på semi-elitnivå med målet att identifiera lämpliga tester för populationen. Det sekundära syftet var att kartlägga och beskriva de fysiska prestationsförmågorna hos populationen. Metod Tvärsnittsundersökning med kvantitativ ansats. Datainsamlingen bestod av fem fältbaserade fysiska tester samt tre maximala styrketester. Tio (n=10) aktiva kvinnliga volleybollspelare på semi-elitnivå deltog i undersökningen. Resultat I analysen noterades vissa signifikanta korrelationer mellan testerna. 3 RM Squat korrelerade statistiskt med Vertikal Hoppförmåga (r= 0,668, p= 0,035) samt 3 RM Hip Thrust (r= 0,721, p= 0,019). 3 RM Hip Thrust korrelerade inte mot något av hopptesterna. För Standing Long Jump (SLJ) noterades ingen signifikant korrelation mot övriga tester. Ett starkt signifikant samband konstaterades mellan Sittande Stöt Med Medicinboll (SMBT) och 3 RM Bänkpress (r= 0,775, p= 0,008). RAST och Beep-testet korrelerade signifikant mot varandra (r= 0,690, p= 0,040), dock inte mot övriga tester. I kartläggningen noterades skillnader i prestationsförmåga hos populationen, där de största skillnaderna observerades hos centerspelarna i styrketesterna och VJT.  Slutsats VJT och 3 RM Squat tycks vara de mest lämpliga testerna för utvärdering av hopp och styrkeförmåga hos kvinnliga volleybollspelare under säsong. Även SMBT och 3 RM Bänkpress verkar vara lämpliga test för utvärdering av prestationsförmåga för övre extremiteterna. RAST-testet var inte ett användbart test för populationen, Beep-testet kan dock användas för att kartlägga konditionsnivån. Med beaktning till resultatet av undersökningen förefaller kartläggning av kvinnliga volleybollspelares prestationsförmågor under säsong genom lämpliga tester vara viktigt för att kunna identifiera skillnader i prestationsförmågor mellan olika spelarpositioner och inom samma spelarposition. / Background Volleyball is a physically demanding sport which puts a high demand on the player's anaerobic, speed, and muscular capabilities, where the requirement for these capabilities is dependant on the player's position. Considering the small number of studies examining physical capabilities in various player positions in female volleyball, more studies examining these aspects are needed.  Aim The primary aim of the study was to statistically analyze physical capabilities during the season in female volleyball players at the sub-elite level to identify appropriate tests for the population. The secondary aim was to map and describe the physical capabilities of the population. Method A Cross-sectional study with a quantitative approach was conducted. The subjects performed five field-based physical tests and three maximal muscular tests. Ten (n=10) female volleyball players at the sub-elite level participated in the study. Results Significant correlations were noted between some of the tests. 3 RM Squat correlated significantly with Vertical Jump Test (VJT) (r= 0,668, p= 0,035) and 3 RM Hip Thrust (r= 0,721, p= 0,019). 3 RM Hip Thrust did not correlate with any of the jump tests. No significant correlation was noted between the Standing Long Jump (SLJ) and other tests. A strong correlation was observed between the Seated Medicine Ball Toss Test (SMBT) and 3 RM Bench press (r= 0,775, p= 0,008). The RAST and Beep-test correlated significantly but not against any other test. (r= 0,690, p= 0,040). Differences in physical capabilities were observed in the mapping, where the largest differences were noted in the middle-blocker position for the maximum strength tests and VJT. Conclusion VJT and 3 RM Squat seem to be the most appropriate tests for evaluating jump and strength capabilities in the lower extremities. In addition, the SMBT and 3 RM Bench press both seem to be appropriate tests for evaluating performance in the upper extremities. The RAST-test does not seem to be a useful test for the population, the Beep-test however can be used to evaluate aerobic performance. Based on the findings of this study, mapping physical capabilities in female volleyball players through appropriate tests during the season seems to be important in order to detect differences in physical capabilities between player positions and within player positions.

No description available.

<p>Autonomous guidance and control techniques for low-thrust spacecraft under multi-body dynamics via reinforcement learning</p>

Hall-effect thrusters (HETs) are among the most commonly used propulsion systems for attitude and orbit control of satellites. As an arrangement in a cluster or individually, equipped with a mechanical suspension, thrust in all three spatial directions can be generated, but requires additional mechanisms and components. Therefore, the Technische Universität Dresden (TU Dresden) is currently working on a concept for developing a Hall-effect thruster with integrated thrust vector control, which would allow steering in all three spatial directions with just a single thruster. This new concept is intended to work solely by influencing the ion beam and should not have any additional mechanical components. The HET will come with a segmented anode to set different electrical potentials at the anode and cause an inhomogeneous distribution of the electric field within the discharge channel, which results in an inhomogeneous force vector distribution at the exit plane. It is assumed that this will generate turning moments around the center of gravity. Deliberately causing those turning moments can therefore be used for steering with just one thruster. This work presents the concept of the propulsion system, gives an outlook on the advantages of its technology and shows capabilities for space applications.

The Late Cretaceous Trail Member of the Ericson Sandstone represents a regionally extensive fluvial system that transported sediments from the Sevier fold and thrust belt and Uinta Mountain uplift to the Western Interior Seaway. The Trail Member is a petroleum reservoir target that has unpredictable production rates due to the unknown behavior and connectivity of channel sandstones. The abundant outcrop, wellbore, and core data available allows for a comprehensive analysis of how the fluvial architecture, connectivity, and reservoir quality change along 65 km of depositional dip. Observations made at Flaming Gorge and Clay Basin (most landward field locations) suggest a highly mobile fluvial system that was influenced by both autogenic channel clustering and allogenic forcing. Evidence is seen for movement along the Sevier fold and thrust belt and early Laramide uplift of the Uinta Mountains. Specifically, three zones identify temporal tectonic changes throughout deposition of the Trail Member. The Upper and Lower Trail zones represent times of low accommodation as the fluvial system must avulse and move laterally to find available space. The Middle Trail zone represents a higher accommodation setting with internal autogenic channel clustering. This shows that on a finer timescale, autogenic processes control sediment distribution, while on a longer timescale, external drivers, specifically tectonics, control the distribution of sediment in the Trail fluvial system. Significant changes were observed within the Trail Member towards the basin. At Northern Colorado, lenticular, fluvial-dominated sands are still common, preserved organic and woody material, mud cracks, and increased bioturbation are observed that are not present elsewhere. The sandstone channels are slightly wider, have more common occurrences of low flow-regime sedimentary structures such as ripples and mud cracks, and appear to be more individually isolated with thin fine-grained material surrounding the channels. On a larger scale, photogrammetric analysis shows a rapid lateral change (0.3 km) from a sand-rich, channel-dominated expression to a mud-rich, channel-poor character. These observations suggest a lower energy fluvial system focused within a possible incised valley showing that the fluvial system is being influenced primarily by eustatic forces, rather than tectonics. Subsurface data from twelve wells located north of the Northern Colorado locality show a rapid (15 km) increase in thickness (97 m to 182 m) and decrease in net-to-gross (89.3% to 65.3%). Early subsidence of the Washakie sub-basin just east of the wells could account for the rapid increase in accommodation. Another possible explanation for the rapid thickness increase to the northeast could be the presence of an incised valley. These possibilities show the complexity of the environment within which the Trail Member fluvial system deposited sediments.

No description available.

Die elektromagnetische Dynamik von axialen Magnetlagern ist im besonderen Maße von den eingesetzten Materialien abhängig. Axiale Flussverläufe machen eine Blechung von Stator und Rotor unwirksam und hohe induzierte Spannungen rufen im Magnetkreis wirbelstrombedingte Gegenfelder hervor. Zusätzliche kompensierende Magnetisierungsströme lassen den messbaren Strom der Steuerspule dem kraftbildenden Hauptfluss vorauseilen. Steigende Anforderungen an die Regeldynamik erfordern daher den Einsatz schwach elektrisch leitfähiger Kernmaterialien (Soft Magnetic Composites) oder eine Berücksichtigung der auftretenden Wirbelstromeffekte in der Regelstrecke unter Anwendung von Systemen gebrochenrationaler Ordnung. Beide Optionen werden in diesem Beitrag aus analytischer Sicht gegenübergestellt und ihre Anwendungsfälle diskutiert.

<p>Detta examensarbete har utförts på Fläktwoods AB i Växjö, som producerar stora axialfläktar för olika industriapplikationer. Syftet är att öka kunskapen om fettsmorda axiella kullager genom FE analyser.</p><p>Projektet har genomförts i fem delsteg för att avgöra påverkan av en eller några få parametrar i taget. De studerade parametrarna är: elementstorlek, kontaktstyvhet, last, lagergeometri (dvs. oskulation), ickelinjär geometri och ickelinjära materialegenskaper (dvs. plasticitet).</p><p>Slutsatsen är att elementstorleken bör väljas fint nog för att ge ett jämnt resultat men grovt nog för att beräkningstiden skal vara rimlig. Kontaktstyvheten har inte stor, men tydlig, inverkan på kontakttrycket och penetrationen. Förändringar av oskulationen leder till förändringar i kontaktellipsens form medan olika laster inte påverkar formen på ellipsen, utan snarare storleken. När det handlar om plasticitet är sträckgränsen den viktigaste faktorn att beakta.</p> / <p>This thesis project was carried out at Fläktwoods AB in Växjö who produces large axial fans for different industry applications. The purpose is to increase the knowledge of grease lubricated axial ball bearings through FE analyses.</p><p>The project was executed into five sub steps to determine the influence of one or few parameters at a time. The studied parameters are: mesh density, contact stiffness, load, bearing geometry (i.e. osculation), geometrical nonlinearity and material nonlinearity (i.e. plasticity).</p><p>It is concluded that the mesh density should be selected fine enough to give a smooth result but course enough to give a reasonable calculation time. The contact stiffness has not a major, but a clear, impact on the contact pressure and penetration. Changes of the osculation lead to changes of the contact ellipse shape and applying different load level does not affect the shape of the ellipse but rather the size. When dealing with plasticity the yield strength is the most important factor to take in consideration.</p>

Ce travail de thèse concerne une transversale complète des Pyrénées centro-occidentales, où on a combiné la thermochronologie basse température (traces de fission sur apatites, TFA) avec une analyse structurale détaillée pour décrire les mouvements verticaux associés à l'évolution du système chevauchant, et pour déterminer l'influence de ce dernier sur le cycle sédimentation/enfouissement/exhumation des dépôts synorogéniques du bassin d'avant-chaine sud (bassins de Jaca et Ainsa). L'analyse TFA complète les données déjà publiées dans la Zone Axiale et la Zone Nord-Pyrénéenne, et constitue la première étude de ce genre dans un bassin d'avant-chaîne pyrénéen. Les données TFA sur la transversale du bassin sud-pyrénéen montrent une diminution vers le sud du degré d'effacement des traces de fission, traduisant la diminution vers le sud de la quantité d'enfouissement, supérieure à 5 km au nord et inférieure à 3 km au sud dans l'hypothèse un géotherme de 25°.km-1. Le contexte géologique montre que l'enfouissement est principalement lié à l'accumulation des dépôts synorogéniques. Les données TFA de la partie nord du bassin montrent un refroidissement d'âge Oligocène supérieur-Miocène inferieur (moyen). Par ailleurs, une nouvelle interprétation de profils de sismiques réflexion dans le bassin de Jaca montre que le chevauchement d'Oturia s'enracine dans le chevauchement de socle de Bielsa, responsable de l'exhumation tectonique hors-séquence du bord sud de la Zone Axiale au Miocène inférieur (-moyen) (Jolivet et al., 2007). Ces résultats attestent donc de l'exhumation tectonique hors-séquence au Miocène inférieur (Burdigalien- ?Langhien) de la partie nord du bassin d'avant-chaine sud-pyrénéen. Des données TFA obtenues dans la Zone Axiale et la Zone Nord-Pyrénéenne confirment la migration générale vers le sud du système chevauchant, et mettent également en évidence la réactivation tectonique hors-séquence du bord nord de la Zone Axiale à l'Oligocène terminal-Miocène inférieur. L'ensemble de ces résultats atteste donc de la réactivation en « pop-up » de la parties interne des Pyrénées centre-ouest à l'Oligocène supérieur-Miocène inférieur (Burdigalien- ?Langhien), postérieurement au scellement du front sud-pyrénéen (Aquitanien- ?Burdigalien) classiquement considéré comme marquant la fin de la compression pyrénéenne. Ces données nous ont permis de proposer un nouveau modèle d'évolution crustale des Pyrénées centro-occidentales en 3 grandes étapes : (i) du Crétacé supérieur à l'Eocène moyen, le prisme est caractérisé par une absence de relief, en lien avec l'inversion de structures extensives crétacées conduisant à l'accrétion de petites écailles crustales ; (ii) la période Eocène supérieur-Oligocène correspond à la collision continentale proprement dite, et est marquée par la création d'importants reliefs associés à l'accrétion d'épaisses unités crustales ; (iii) au Miocène inférieur, la partie interne du prisme pyrénéen est réactivée. / In this work on a complete transect of the west-central Pyrenees, we combine low temperature thermochronology (apatite fission tracks, AFT) with a detailed structural analysis to describe vertical movements related to the thrusting system evolution, and to determine the influence of the latter on the sedimentation/burial/exhumation cycle of the synorogenic deposits of the southern foreland basin (Jaca and Ainsa basins). AFT analysis from a transect of the south-Pyrenean basin show the southward decrease of the fission track reset level from the southern edge of the Axial Zone to the South-Pyrenean frontal thrust, implying the southwards decrease of the burial amount from more than 5km in the north to less than 3km in the south assuming an average geothermal gradient of 25°C.km-1. The structural setting of the Jaca basin attests that the burial of the synorogenic sediments was mainly due to the sedimentary accumulation. AFT data from the northern part of the basin display a late Oligocene-early (middle) Miocene cooling event. New interpretation of industrial seismic reflection profiles across the Jaca basin suggests that the Oturia thrust is rooted in the Bielsa basement thrust, responsible for the early (-middle) Miocene out-of-sequence tectonic reactivation of the southern flank of the Axial Zone (Jolivet et al., 2007). These results reveal a lower Miocene (Burdigalian -?Langhian) out-of-sequence episode of tectonic activity of the interior of the south-Pyrenean foreland basin. AFT data from the Axial Zone and the North-Pyrenean Zone confirm the general southward migration of the thrusting system, and also bring evidence of the late Oligocene-lower Miocene out-of-sequence tectonic reactivation of the northern flank of the Axial Zone. All these results attest of a late Oligocene-lower Miocene (Burdigalian-?Langhian) 'pop-up' reactivation of the inner part of the west-central Pyrenees, younger than the sealing of the south-Pyrenean front (Aquitanian-?Burdigalian) which is classically considered to mark the end of the Pyrenean compression. These results lead us to propose a new crustal scale evolution model of the west-central Pyrenees in 3 stages: (i) From the Late Cretaceous to the middle Eocene, the orogenic prism is characterised by the absence of relief, related to the inversion of Cretaceous extensional structures leading to the accretion of thin crustal units; (ii) The late Eocene-Oligocene stage corresponds to the continental collision, marke d by the creation of important relief associated with the accretion of thick crustal units; (iii) During the early Miocene, the inner part of the Pyrenean wedge is tectonically reactivated.

In Old West Norse there is mention of an Arctic skin and osier boat, which was paddled with Old West Norse (húð)keipr, diminutive keipull, formed on Germanic *kaip- ’bend, unfold’ according to the construction method. In East Norse there was a corresponding wooden boat, e.g. Swedish själ-myndrick, formed on mynda verb ‘paddle’ (&lt; Primitive Norse *mundian ‘aim at a certain goal, take aim’). In the provinces south of this verb’s area of distribution there occurs instead svepa verb ’paddle’ (&lt; Primitive Germanic *swaipōn ‘swing’). The earliest instances of Nordic rowing navigation are found in Norway and Denmark. Instances of rowing in the Baltic area are found on some picture stones from about the 6th century. But oarlocks with a grommet were probably used already for the steering oar in the paddled boats of the Bronze Age. An early oarlock (with a grommet) is that made of a goose-necked piece of wood, Old Swedish hār, Old West Norse hár (&lt; *hanhu-, *hanha- ‘branching, fork of a branch’) and Old West Norse keipr (&lt; *kaip- ‘something with a crooked or bent (-back) shape’. The word hár exists as a first element in Old Swedish hā-band ‘oar-loop’, Old West Norse há-bora ‘oar-port’ etc. Old West Norse keipr ‘oarlock’ has no ancient compounds. East Nordic hamna (&gt; Finnish hamina), Old Danish hafnæ (Old Frisian hevene) and West Nordic hamla (Faroese homla, Old English hamele, hamule) ‘oar-loop’ occurred early on the oarlock with a grommet; hamna may be a derivation of the stem in Primitive Norse *haƀan verb ‘hold (fast)’, alternatively *hafna- ‘clasp something’; hamla derives from a Germanic *hamilōn with the meaning ‘bridling band’. Centrally in the Nordic area hamna (Danish havne) and hamla ‘oar-loop’ were also used denominatively with the meaning ‘row pushing in a hamna/hamla (oar-loop)’. In addition there is the Swedish dialectal sväva (~ sveva, svävja) ‘row (back, break etc.) with pushing rowing’ and in the group of older verbs for rowing there is East Swedish hopa &lt; Primitive Norse *hōƀian ‘fix one’s eyes upon a certain goal (in the distance)’. With word formations on Germanic *þulna- ‘wooden plug’ there arose from the Middle Ages and in the North Sea countries a new terminology for the oarlock: Norse tull, toll ‘oarlock with a thole pin’. Even younger concepts are tullgång ‘oarlock with two thole pins’, årklyka, årgaffel ‘oar crutch’. A distinctive trait of Old Swedish hār and hamna, Old West Norse hár and hamla and keipr and other common words for the oarlock is in these words the shift of meaning ‘oarlock of a specific kind’ &gt; ‘almost any kind of oarlock’. Finally, the question arises whether or not the word svear of a tribe by Lake Mälaren could be tied to the paddling through a connection to the stem of the verbs svepa and sväva. / <p>Ingår även i serie: Studier till en svensk dialektgeografisk atlas, 8</p>