Indiana University-Purdue University Indianapolis (IUPUI) / This thesis presents a comprehensive study of the effects of material, geometric and operational parameters on flat belt-drives steady-state belt stresses, belt slip, and belt-drive efficiency. The belt stresses include: belt rubber shear, normal, axial and lateral stresses; reinforcements tension force; and tangential and normal belt-pulley contact stresses. Belt slip is measured using the driven over driver pulleys’ angular velocity ratio. Each parameter was varied over a range to understand its impact on the steady-state belt-drive response. The material parameters studied are belt axial stiffness and damping, belt bending stiffness and damping, and belt-pulley friction coefficient. The geometric parameters studied are pulley center distance, pulleys diameter ratio, and belt thickness. The operational parameters studied are the driver pulley angular velocity and the driven pulley opposing torque (load). A high-fidelity flexible multibody dynamics parametric model of a two-pulley belt-drive system was created using a commercial multibody dynamics code. In the model the belt’s rubber matrix is represented using three-dimensional brick elements and the belt’s reinforcements are represented using one dimensional beam elements at the top surface of the belt. An asperity-based Coulomb friction model is used for the friction forces between the pulley and belt. The pulleys are modeled as rigid bodies with a cylindrical contact surface. The equations of motion are integrated using an explicit solution procedure. Unlike prior models which use one-dimensional truss or beam elements for the belt, the present model uses a three-dimensional belt model which introduces the effect of the thickness of the belt rubber matrix (modeled using brick elements). This enables a more accurate prediction of the belt stresses and slip than prior models. This thesis resolves in more details the complex stick-slip friction behavior of an axially flexible belt coupled with the shear effects of a flexible rubber cushion and at the same time shows the effect of the main system parameters on this stick-slip behavior. Some of the important conclusions of the thesis include: (1) the driver pulley has two distinct contact zones - a negative traction zone and a positive traction zone - while only one traction zone is present over the driven pulley; (2) the width of the negative traction zone on the driver pulley increases with the belt-pulley coefficient of friction and decreases with the belt axial stiffness; (3) the maximum belt tension and normal contact stress occur on the driver pulley and increase with the belt thickness, belt axial stiffness, and coefficient of friction; (4) belt-drive energy efficiency increases with the belt axial stiffness, and decreases with belt thickness, belt bending damping, belt operating speed, and operating torque load. The belt-drive modeling methodology presented in this thesis which enables accurate prediction of the belt stresses and slip can in turn be used to more accurately predict the fatigue life, wear life, and energy efficiency of belt-drives.

Die Arbeit befasst sich mit der Simulation von Zweiwellen-Zahnriemengetrieben und deren Vorspannmethoden, insbesondere mit der relativ neuen Methode Spannring (ROLL-RING®). Das Ziel der vorliegenden Arbeit ist es, ein analytisches Simulationsmodell zu entwickeln, mit dem grundlegende Erkenntnisse über das statische und dynamische Verhalten solcher ringgespannten Zahnriemengetriebe gewonnen werden können. Für einen exemplarischen Vergleich der Vorspannmethoden, werden außerdem analytische Simulationsmodelle für Zahnriemengetriebe ohne Spannelement und mit federgespannter Rolle erstellt. Als weiteren Bestandteil der vorliegenden Arbeit wird eine Dimensionierungsvorschrift für ringgespannte Zahnriemengetriebe abgeleitet, bei der sowohl statische als auch dynamische Vorgänge im Getriebe berücksichtigt werden können. Anschließend wird der Einfluss der relevanten Parameter auf das Verhalten des ringgespannten Getriebes untersucht. Alle erstellten Simulationsmodelle werden sowohl experimentell an Versuchsständen als auch mittels FEM-Vergleichsrechnung validiert. Die dafür benötigten Getriebeparameter wurden ebenfalls experimentell ermittelt. Abschließend folgt der exemplarische Vergleich der Vorspannmethoden anhand von drei Simulationsbeispielen und einem experimentellen Vergleich des Wirkungsgrads. / This dissertation deals with the simulation of two-shaft timing belt drive and its pre-tension methods. Special attention is given to the relatively new method tensioning ring (ROLL-RING®). The target of the present work is to develop an analytical simulation model, with this fundamental understanding of the static and dynamic behavior of such ring-tensioned timing belt drives can be gained. For an exemplary comparison of pre-tension methods, analytical simulation models for synchronous belt drive without pre-tension element and with tensioner pulley with spring will be created. As another part of the present work a dimensioning specification for ring-tensioned toothed belt drives was deduced. This specification can be considered in both static and dynamic processes in the transmission. Then, the influence of relevant parameters on the behavior of the ring-tensioned timing belt drives is researched. All created simulation models will vali-date both experimental and FEM using comparative calculation. The parameters re-quired for the transmission were also experimentally determined. Finally, the exemplary comparison of pre-tensioned methods basis of three examples of simulation and an ex-perimental comparison of energy conversion efficiency follow.

No description available.

The recent discovery of objects near the 5:1 Neptune resonance prompts the study of the size, structure, and surface properties of this population to determine if these parameters are consistent with a ‘Nice model’ type evolution of the outer Solar System. Previous TNO discovery surveys have primarily targeted the ecliptic plane, where discovery of high inclination objects such as the 5:1 resonators is unlikely, and theoretical work on the evolution of the outer Solar System has focused on structure in and around the main Kuiper belt and largely ignored the distant resonant TNOs. I tracked these objects for several semesters, measured their positions accurately, and determined precise orbits. Integrating these orbits forward in time revealed that three objects are 5:1 resonators, and one object is not resonant but may have been resonant in the past. I constrained the structure of the 5:1 resonance population based on the three detections and determined that the minimum population in this resonance was much larger than expected, 1900(+3300,−1400) with H < 8. I compared this large population with the orbital distribution of TNOs resulting from a Nice model evolution and determined that the population in the real 5:1 resonance is ~20–100 times larger than the model predicts. However, the structure of the 5:1 resonance in this model was consistent with the orbital distribution I determined based on the detections. The orbital distribution of the scattering population in the Nice model is consistent with other models and survey results, leading to the conclusion that the 5:1 resonance cannot be a steady state transient population produced via resonance sticking from the scattering objects. To test the origin of the 5:1 resonators, I measured the objects’ surface colors in multiple wavelength ranges and compared their surface reflectance to TNOs from a large color survey, ColOSSOS. The 5:1 resonators have a consistent selection criteria to the TNOs from the ColOSSOS survey, so these samples have known selection biases and can be usefully compared to each other. The surfaces of the three 5:1 resonators showed three different spectral reflectance shapes, indicating that these three objects do not share a common formation location. The surface properties and orbital distribution of current 5:1 resonators are consistent with the remnant of a large captured population, partially resupplied by the scattering objects. However, the scattering event which produced this large 5:1 population remains unexplained. / Graduate

Thesis (MSc (Earth Sciences))--University of Stellenbosch, 2010. / ENGLISH SUMMARY: Regional mapping of the Stinkbank granite in the south Central Zone of the Damara Belt, focused on an area of ca. 150 km2 in the SW parts of the granite along well exposed sections of the Khan River to the SW of the town of Usakos. The granite forms part of the regionally widespread granite suite of Salem-type granites that intruded at ca. 550-540 Ma into amphibolite-facies rocks of the Damara Supergroup. The Stinkbank granite is intrusive into the regional-scale, NE-trending D2 Kransberg syncline, cored by schists of the Kuiseb Formation and surrounded by marble units of the Karibib Formation. The granite comprises three major lithotypes that have intruded in sequence. The earliest granites are represented by biotite-rich megacrystic granites, followed by leucocratic megacrystic granites and a final stage of voluminous, garnetiferous and tourmaline-bearing, medium-grained leucogranites. Contact relationships with the wall rocks are, for the most part, concordant, documenting the largely sheet-like geometry of the granites. Internal contacts between different granite phases are well preserved and indicate that the granites have intruded as shallowly-dipping, largely concordant sheets. Intrusive contact relationships and petrographic and geochemical characteristics indicate that each of the three major granite phases represented a distinct emplacement pulse. Successive emplacement of the granite sheets point to the assembly of the Stinkbank granite from the top down, with younger sheets intruding structurally below earlier emplaced granite sheets. This has created a pseudostratigraphy within the Stinkbank granite. The mapping of the internal contacts shows that the granite sheets were progressively folded into NE-trending, upright folds, parallel to D2 folds in the surrounding wall rocks. NE-trending magmatic and solid-state foliations in all granite phases are axial planar to the folds and underline the syntectonic emplacement of the Stinkbank granite during the D2 NW-SE subhorizontal shortening. Based on the intrusive relationships and the progressive deformation of granite phases, an intrusive sequence can be developed for the Stinkbank granite. The earliest granite phases were emplaced during the onset of the regional D2 deformation, parallel to the subhorizontal bedding. Continued granite sheeting led to the vertical growth of the sheet-like granite and bending of the wall rocks above the inflating granite sheets, leading to the laccolithic geometry of the SW parts iii of the Stinkbank granite. Progressive deformation, folding of the granite sheets and fold amplification resulted in fold interference patterns in the SW parts of the Stinkbank granite. The Stinkbank granite represents a mid-crustal granite with well-preserved granite sheeting that was assembled during regional deformation. Granite sheeting and progressive deformation illustrate the interplay between (1) regional strains, and (2) the orientation and presence of pre-existing wall-rock anisotropies (bedding) and their significance for the magmatic assembly and progressive deformation of the granite. / AFRIKAANSE OPSOMMING: Regionale kartering van die Stinkbank graniet in die suidelike Sentrale Sone (sSS) van die Damara Gordel. Die studie fokus op die area van ongeveer 150 km2 in die SW dele van die graniet, langs n goed blootgestelde seksie van die Khan Rivier, SW van Usakos. Die graniet vorm deel van n wydverspreide suite van Salem- tipe graniete wat tussen 550-540 Ma in die amfiboliet fasies gesteentes van die Damara Supregroep ingedring het. Die Stinkbank graniet kom voor in regionale –skaal , NE – neigende D2 Kransberg Sinklinorium, wat bestaan uit skis van die Kuiseb Formasie en marmer van die Karibib Formasie. Die graniet bestaan uit drie hoof fases wat in volgorde ingedring het. Die oudste graniet is die biotiet-ryke megakristiese graniet, gevolg deur die leukokratiese megakristiese graniet en laastens die leukograniet. Kontak verhoudings met die wandgesteentes is grootendeels konkordant en dit dui op die feit dat die graniet uit lae bestaan. Die interne kontakte tussen die verskillende graniete is goed preserveer en dui aan dat die graniete voorkom as vlak lêende lae. Kontakverhoudings, petrografie en geochemiese karakteristieke dui aan dat elk van die die drie tiepes graniet uniek is. Die volgorde van intrusie van die Stinkbank graniet het voorgekom van bo na onder. Dit het n “skyn-stratigrafie” tot gevolg gehad. Kartering van die interne kontakte tussen die graniete het getoon dat die graniet lae is deurentyds gevou na NE- neigende, regop voue, parallel aan die D2 voue in die omringende wandegesteentes. NE- neigende magmatiese en soliede stadium foliasies in al die graniete is asvlak planêr aan die voue en dui ook op die syn-tektoniese intrusie van die Stinkbank graniet gedurende die D2 , NW-SE subhorisontale verkorting. Intrusiewe verhoudings en die progressiewe deformasie van die graniet, dui dat n volgorde verkry kan word vir die Stinkbank graniet. Die oudste graniet fase het ingedring gedurende die begin van die streekse D2 deformasie, parallel aan die subhorisontale gelaagdheid. Aanhoudende graniet-lae intrusies het gely tot die groei van n laag-ryke graniet en die buiging van die omliggende wangesteentes om dit n lakoliet vorm te gee in die SW dele van die Stinkbank graniet. Progressiewe deformasie, vouing van graniet lae en vergroting van voue het tot vou-interferensie patrone in die SW dele van die Stinkbank graniet tot gevolg gehad. Die Stinkbank graniet stel n middel- kors graniet met goed gepreserveerde gelaagdheid, wat gedurende regional deformasie ingedring het, voor. Graniet lae en progressiewe deformasie illustreer die verhouding tussen (1) regionale spanning en (2) die orientasie en teenwoordigheid van voorafbestaande wandgesteente anisotropie (gelaagdheid) en hulle belangrikheid vir die opbou en deformasie van die graniet.

The thin-skinned structures of the late Paleozoic Ouachita thrust belt intersect the basement structures of the Southern Oklahoma aulacogen beneath the Mesozoic strata of the Gulf Coastal Plain in southeastern Oklahoma. The Ouachita thrust belt forms a large northwest-directed salient which extends primarily in the subsurface from central Mississippi northwestward to Arkansas and eastern Oklahoma, and from there, southwestward toward central Texas. Kinematics are complicated in the center of the Ouachita salient, where the average southwesterly strike of thrust faults is nearly perpendicular to average trend of compressional basement structures in the Southern Oklahoma aulacogen (Arbuckle uplift) and Muenster arch. Furthermore, the frontal fault of the Ouachita thrust belt curves sharply eastward around the southeastern end of the Arbuckle uplift, and bends sharply to the west between the Arbuckle uplift and the Muenster arch farther south in Texas. Nine new interpreted structural cross sections show the structural complexity of the area where the Ouachita thrust belt intersects the Arbuckle uplift and Muenster arch. Detailed study of the structural geology of the Ouachita Mountains and Arkoma basin indicates that along-strike changes in structural style evidently are related to along-strike changes in mechanical stratigraphy (relative thicknesses of weak units, in contrast to stiff units). The middle part of the Stanley Group (Formation) evidently serves as a wavelength transition and/or volume compensation zone. Along-strike change in stratigraphic level of detachments and abrupt eastward thickening of the Atoka Formation along the Ouachita thrust front strongly affected the structural style of the Ouachita thrust belt. Regional stratigraphy, palinspastic restorations of the footwall cutoff of the Ti Valley fault, and an abrupt change in character of seismic reflectors indicate an abrupt facies transition in the Middle Ordovician-Mississippian succession along the southeastern flank of the Arbuckle uplift and southwestward toward the deep southeastern part of the Ardmore basin. Out-of-syncline structures in the Bryan smallscale salient, distinct sub-thrust angular unconformities imaged on seismic profiles, and sediment dispersal patterns in the early Atokan-Desmoinesian strata of the northern Fort Worth basin (south of the Muenster arch) all indicate that the Tishomingo-Belton and Muenster structures were pre-thrust structural highs.

The deformed Permian Dun Mountain Ophiolite Belt (DMOB) forms the basement of the Dun Mountain-Maitai terrane and is traceable through the entire length of New Zealand. The DMOB contains a variably serpentinised mantle portion and a crustal portion containing gabbros, dolerites, cross cutting dikes and extrusives, together they are similar to oceanic crust. The initial crustal portion, however, is atypical when compared to other ophiolites, being thin and lacking a sheeted dike complex, but has well spaced inclined intrusive sheets and sills. At least four post-Permian deformation periods affect the DMOB; collision and rotation during emplacement of the DMOB on the Gondwana margin, compression during Mesozoic orogenies, extensional deformation during the Gondwana break-up and transpressive deformation related to the modern plate boundary through New Zealand. Structural work in the Northern Bryneira Range focused on well preserved outcrops to investigate crustal growth and contemporaneous deformation during the Permian. Structural evidence of Permian deformation was determined by examination of pseudostratigraphy, structures constrainable to the Permian, and the geometric relationships with the overlying Maitai sedimentary sequence. Crosscutting by intrusive phases was used to determine a chronological order of crustal growth and deformation episodes. It was concluded that all deformation was extensional and that two major phases of magmatism were separated by a period of deformation and were followed by ongoing syn-sedimentary deformation during the deposition of the Maitai Group. After removal of Mesozoic rotation, the resulting orientations of paleo-horizontal markers and diverse orientations of intrusive sheets were analysed. Two hypothesises were tested to assess the origin of inclined intrusive sheets: a) that the diverse orientations were the result of tectonic rotation coeval with the intrusion of dikes. b) that primary orientations of the sheets had been diverse. Results show that the sheets were intruded with diverse orientations, probably related to variation in the principle horizontal stress over time. Further rotation of the assemblage of sheets occurred during the last stages of magmatism and during the subsequent period of sedimentation. The last stage probably relates to large scale normal faulting during the development of the sedimentary basin. iii

Since the 1970s, waves of deindustrialization have dramatically transformed the urban Rust Belt. The plight of cities in this region is well documented by scholars. The story they present upholds central assumptions in theories of urban growth, mainly new cities grow in new economic regions at the expense of others. This dissertation challenges this notion by addressing the following question: What are the different economic trajectories Rust Belt cities have taken over the course of global economic restructuring from 1970 to 2000? In this research, 69 Rust Belt cities are classified into three different categories based on their performance on a quality of life index over this time period: stable, struggling, and devastated. Then, conventional quantitative methods are used to map changes in employment trends onto the cities in each category. This step provides a general picture of economic restructuring experiences in these cities, which shows all lose manufacturing employment, but increases in business services employment distinguishes stable cities while increases in professional services employment distinguishes devastated cities. Next, an innovative methodology is used to identify different kinds of economic transitions for different types of cities. The analysis shows larger, stable cities have been able to reorganize their local economies into producer service-based economies. It also indicates manufacturing remains central to the local economies in smaller, stable cities, and finally, all devastated cities are developing healthcare-based local economies. Finally, two stable and two devastated cities are examined in-depth to provide a detailed description of local economic transformations. The stable cities have combined local R&D facilities with a strong infrastructure of specialty manufacturers to become high-tech production sites. This change has fueled business services development in these cities. Devastated cities are holding onto old manufacturing while greatly expanding hospital-based employment. Overall, this dissertation makes a contribution by using multiple and innovative methods to develop a rich portrait of the economic reorganization of the urban Rust Belt. This portrait questions central assumptions in theoretical understandings of urban growth and serves as a foundation for an examination of the causes of successful local economic transformation.

The American Cordillera, a major mountain belt spanning>15000 km along the western margins of North and South America, formed as a result of crustal shortening and magmatism during ocean-continent convergence. These mountains were the loci of addition and redistribution of continental crust. The contributions presented here address the style, timing, and kinematics of underthrusting of continental crust in the retroarc of the central Andes as well as the rapid burial and metamorphism of forearc rocks that contributed to magmatism in the Canadian Cordillera. This work involved geological mapping and structural analysis coupled with geo- and thermochronological analysis. In the central Andes, results confirm a southward transition in structural style and magnitude of Cenozoic shortening that coincides with the disappearance of a thick Paleozoic basin that accommodated major Cenozoic shortening. U-Pb and (U-Th)/He results also demonstrate that thrust belt kinematics in northwestern Argentina were greatly influenced by pre-orogenic heterogeneities in Cretaceous rift architecture. Results from western Canada reveal that rapid underthrusting of forearc rocks occurred during Late Cretaceous time, likely associated with an episode of shallow subduction. This event did not result in basement-involved foreland uplifts thought to be a signature of shallow subduction in the western United States and central Argentina. Taken together, this work has the major implication that variations in the pre-orogenic upper crustal architecture strongly influence the behavior of the continental lithosphere during orogenesis, a result that challenges geodynamic models that largely neglect upper plate heterogeneities.

Rust Belt and Other Stories is a collection of stories exploring characters in the bleak moments when social oppression challenge the perceived meaning of their lives. The disenchantments are influenced by distinctive settings, which set the tone for the stories. Place is an active force shaping the protagonists and adding to the nuance of character relationships, dialogue and philosophical outlooks.