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Structural analysis of the Jupiter and Camelot areas, Southern North SeaFullarton, Lisa Diane January 2000 (has links)
No description available.
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An Enhanced Algorithm to Find Dominating Set Nodes in Ad Hoc Wireless NetworksNanuvala, Naresh 04 December 2006 (has links)
A wireless ad hoc network is a collection of wireless mobile nodes forming a temporary network without the aid of any established infrastructure or centralized administration. A connection is achieved between two nodes through a single hop transmission if they are directly connected or multi-hop transmission if they are not. The wireless networks face challenges to form an optimal routing protocol. Some approaches are based on a dominating set, which has all the nodes either in the set or within its neighborhood. The proposed algorithm is an enhancement of the distributed algorithm proposed by Wu and Li. The simulation results from the new algorithm are compared to results from Wu and Li’s algorithm. The simulation results show that the average dominating set of nodes decreased considerable after applying the new algorithm. The decrease in number of dominate set nodes is not very much noticeable in low density space.
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A Microfluidic, Extensional Flow Device for Manipulating Soft ParticlesMotagamwala, Ali Hussain 05 December 2013 (has links)
A computer-controlled microfluidic extensional flow device is developed for trapping and manipulating micron-sized hard and soft particles. The extensional flow is generated in a diamond-shaped cross-slot that has each corner connected to a pressure-controlled liquid reservoir. By employing an imaging-based control algorithm, a particle can be made to move to an arbitrary position within the slot by adjusting the reservoir pressures and hence the fluid flow rates into/out of the slot. Thus, a soft particle can be trapped indefinitely at a point within the slot, and a known hydrodynamic force can be applied to study the dynamics of stretching and breakup of the particle. Alternatively, adhesion or coalescence dynamics of soft particles may be investigated by effecting a controlled collision between two particles. The device is validated by measuring the low interfacial tension of a compatibilized oil-water interface.
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A Microfluidic, Extensional Flow Device for Manipulating Soft ParticlesMotagamwala, Ali Hussain 05 December 2013 (has links)
A computer-controlled microfluidic extensional flow device is developed for trapping and manipulating micron-sized hard and soft particles. The extensional flow is generated in a diamond-shaped cross-slot that has each corner connected to a pressure-controlled liquid reservoir. By employing an imaging-based control algorithm, a particle can be made to move to an arbitrary position within the slot by adjusting the reservoir pressures and hence the fluid flow rates into/out of the slot. Thus, a soft particle can be trapped indefinitely at a point within the slot, and a known hydrodynamic force can be applied to study the dynamics of stretching and breakup of the particle. Alternatively, adhesion or coalescence dynamics of soft particles may be investigated by effecting a controlled collision between two particles. The device is validated by measuring the low interfacial tension of a compatibilized oil-water interface.
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Petrologia e geoquímica do Plúton Pilõezinhos, domínio central, Província Borborema.LIMA, Jefferson Valdemiro de 25 July 2016 (has links)
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Previous issue date: 2016-07-25 / CAPES / O Plúton Pilõezinhos (PP) compreende uma intrusão alongada, de ~ 100 km2, no
Domínio Central (Subprovíncia Transversal) da Província Borborema e caracterizada por
sienogranito e monzogranito equigranular a porfirítico, contendo raros enclaves e xenólitos. O
PP intrude metassedimentos brasilianos e ortognaisses tonianos, num contexto estrutural
gerado pela movimentação sincrônica das zonas de cisalhamento Remígio-Pocinhos (ZCRP)
de direção E-W e cinemática destral, e Matinhas de direção NE-SW e cinemática sinistral. Os
granitos do PP apresentam química mineral caracterizada por fases máficas enriquecidas em
halogênios e em Fe, com biotitas ricas na molécula de siderofilita e anfibólios com
composição variando de hastingsita a Fe-tchermakita. São classificados quimicamente como
granitos aluminosos e ferro-potássicos com alto teor de álcalis totais. Apresentam alto
conteúdo de HFSE e ETR, com exceção do Eu, que apresenta uma anomalia negativa
característica de granitos tipo-A. O contexto estrutural, associado às feições mineralógicas e
químicas sugere que são granitos tipo-A2. Dados de U-Pb em zircões por LA-ICP-MS
indicam que esses granitos foram colocados, a 566 ± 3 Ma. As condições termobarométricas
de cristalização, definidas a partir dos dados de química mineral são: temperatura variando de
745 a 1003,7 °C e pressão de 4,28 a 5,95 Kbar, que corresponde a profundidades de 15 a 20
km, próximo ao limite crosta média/crosta superior. A mineralogia máfica rica em ferro e a
presença de ilmenita primária sugerem cristalização sob condições de baixa fO2 (abaixo do
tampão FMQ). As assinaturas químicas e isotópicas obtidas nesses granitos (εHf = -16,0 a 18,6
e εNd = -14,73 a –15,81) sugerem origem a partir de fusão parcial de material
infracrustal, entretanto os valores TDM determinados para o PP (1,9 a 2,03 Ga por Sm-Nd e
1,74 a 1,86 Ga por Lu-Hf ) são mais baixos que os observados no embasamento da região
estudada, sugerindo pequena contribuição de material juvenil. A partir de comparações
químicas e isotópicas com outros granitoides e rochas do embasamento, foi definido que o
material crustal envolvido na formação do PP corresponde aos gnaisses tonalíticos do
Complexo Serrinha Pedro Velho, enquanto que o componente juvenil se assemelha ao mesmo
material que participou da origem do Plúton Curral de Cima, intrusão tonalítica alojada a leste
na mesma zona de cisalhamento. O modelamento químico, associado a feições petrográficas
sugere cristalização fracionada como um processo atuante durante a evolução magmática
desses granitos. Em relação ao mecanismo de transporte, o magma granítico que gerou o PP
ascendeu desde a crosta inferior até um nível crustal mais superficial através das estruturas de
cisalhamento, por meio do mecanismo chamado fluxo penetrativo, onde o elevado conteúdo
de halogênio pode ter facilitado este processo. Esses granitos são semelhantes aos do
Complexo Solânea, intrudidos a norte da ZCRP, no Domínio Norte da Província Borborema,
sugerindo não haver fortes diferenças entre esses dois domínios, ou estes apresentam a mesma
assinatura isotópica, e evoluíram juntos durante o Ediacarano. Ambas as intrusões são
comparáveis aos granitoides transalcalinos Fe-K do leste da Nigéria, sugerindo que esse tipo
de magmatismo esteja relacionado a um evento extensivo associado a zonas de cisalhamento
transtensionais durante a consolidação do Supercontinente Gondwana, que se estende desde a
Borborema até o lado Africano de Gondwana na Nigéria oriental. / The Pluton Pilõezinhos (PP) comprises an elongate intrusion, ~ 100 km2, located in the
Central domain (transversal subprovince) of the Borborema Province and characterized by
equigranular to porphyritic, syenogranite and monzogranite containing rare enclaves and
xenoliths. The PP intrude in Brasiliano metasediments and Tonian orthogneisses, in a
structural context related to the synchronic movement of the E-W-striking dextral RemigioPocinhos
Shear Zone and the NE-SW-striking dextral Matinhas Shear Zone. These granites
have mineral chemistry characterized by mafic assemblage enriched in halogens and Fe, with
siderophillite-rich biotite and amphibole with composition ranging from hastingsite to Fetschermakite.
They are classified chemically as ferro-potassic, aluminous granites, with high
content of total alkalis. They have high content of HFSE and REE, except Eu, which display
an negative anomaly characteristic of granites type-A. The structural context associated the
mineralogical and chemical features suggest that are A2-type granites. U-Pb data on zircons
by LA-ICP-MS indicate that these granitic rocks were emplaced to 566 ± 3 Ma. The
crystallization conditions defined from the mineral chemical data are: temperature ranging
from 745 to 1003.7 °C and pressure from 4.28 to 5.95 kbar, corresponding to depths of 15 to
20 km, close to the intermediate crust/ upper crust limit. The Fe-rich mafic mineralogy and
the presence of primary ilmenite suggest crystallization under conditions of low fO2 (below
the FMQ buffer). The chemical and isotopic signatures evidenced in these granitic rocks (εHf
= -16.0 to -18.6 and the εNd = -14.73 to -15.81) suggest originating from partial melting of
infracrustal material, however TDM values determined for the PP (1.9 to 2.03 Ga from Sm-Nd
and 1.74 to 1.86 Ga from Lu-Hf) are lower than those observed in the basement of the study
area, suggesting small contribution of juvenile material. From chemical and isotopic
comparisons with other granitoids and basement rocks it was defined that the crustal material
involved in the formation of PP corresponds to tonalitic gneiss of Serrinha Pedro Velho
Complex, while the junenile component is similar to the same material which gave rise to
Curral de Cima Pluton, tonalitic intrusion housed to the east in the same shear zone. The
chemical modeling, combined with petrographic features suggests fractional crystallization as
an active process during the magmatic evolution these granitoids. In relation to the transport
mechanism, the granitic magma of PP ascended from the lower crustal to a shallower crustal
through the shear structures, by the mechanism called pervasive flow where the high halogen
content may have facilitated this process. These granites are similar to Solânea Complex,
intruded the northern the ZCRP in Central domain of the Borborema Province, suggesting no
strong differences between these two subprovinces, or these two have the same isotopic
signature, and evolved together during the Ediacaran. Both intrusions are comparable to
transalkaline, Fe-K granitoids of the eastern Nigeria, suggesting that this type of magmatism
is associated with an extensive event related with transtensional shear zones in the
consolidation of Gondwana Supercontinent, which extends from the Borborema to the
African side of Gondwana in eastern Nigeria.
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Investigating the effect of a weak lower crust on Basin and Range extensional historyChristopher Calvelage (10897515) 22 July 2021 (has links)
The deformation mechanisms responsible for the extension and rifting in Basin and Range extension over the past ~36 Ma, and their relative importance remain debated. Slab rollback, lithospheric body forces, and relative plate motions have all been shown to contribute, but the relative importance of each mechanism is not fully understood. Here, we build three-dimensional (3D) steady state geodynamic models to simulate the full tectonic reconstruction of Basin and Range extension and compare these results with known geologic field observations and other detailed reconstructions of surface deformation. Our modeling approximates lithospheric deformation through Stokes flow in a spherical cap of variable viscosities. By applying reconstructed boundary conditions, crustal thickness, and surface elevation at 17 Ma, and varying lithospheric viscosity we map out the predicted response of the surface motions and lower crustal flow for different assumed lithospheric viscosity contrasts and investigate the origin of core complex formation. Comparisons between predicted model deformation and geologic field observations from metamorphic core complexes and exposed fluorite deposits indicate: (1) The primary driving force of the formation of geologic features in the western US is regional gravitational collapse focused in the lower crust. Plate motions are second order by comparison at this time period and act to rotate velocities near the plate boundary. (2) A weak lower crust facilitates metamorphic core complex formation and extension in the Nevadaplano. Lateral extrusion of the lower crust serves as a mechanism for both core complex formation and the flattening of the Moho that is observed at present day. (3) Lower crustal flow is a contributes to the rotation and tilt of the Colorado Plateau and formation of the Rio Grande Rift.
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Modeling of Extensional Behaviour of PolymersPocher, John 10 1900 (has links)
The use of polymeric materials in the manufacturing industry has vastly increased since the 1950’s. Because of the large amounts of material involved in modern processing operations, attempts have been made over the years to numerically simulate the processes, in the hope of optimizing operating parameters. However, in contrast to other, more traditional materials such as steel or glass, there is not a well understood connection between the microscopic structure and the (highly non-linear) macroscopic physical response of polymers. Because of this lack of microscopic cause - macroscopic effect knowledge, many descriptions of the physical response of polymers are largely phenomenological ones; that is, the equations used to model the stress/strain response make no attempt to convey information about the microscopic structure of the material.</p> <p> In the present work, five constitutive equations - Mooney-Rivlin, Ogden, G’Sell Two-term Polynomial and K-BKZ - are used to model the stress/strain response of two different polymers commonly used in thermoforming and blowmolding operations, ABS and HDPE, to uniaxial elongation and equibiaxial extension. The models are compared to experimental stress/strain data obtained from an industrial source, and the applicability of their predictions are investigated with regards to variations in strain, strain rate and temperature. Lastly, since the vast majority of real processes involve biaxial, not uniaxial, deformations, the ability of the models to predict equibiaxial response using parameters fit solely to uniaxial data is considered, in order to investigate the possibility of being able to forego the need for expensive, difficult biaxial tests. / Thesis / Master of Engineering (MEngr)
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LAYERED POLYMERIC SYSTEMS:NEW PROCESSING METHODS AND NOVEL MECHANICAL DESIGN IN EXTENSIONAL RHEOLOGYHarris, Patrick James 09 February 2015 (has links)
No description available.
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Entry flow of viscoelastic fluids at macro- and micro-scaleSousa, Patrícia Catarina Saraiva de January 2010 (has links)
Tese de doutoramento. Engenharia Química e Biológica. Faculdade de Engenharia. Universidade do Porto. 2010
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Piezo-on-Silicon Microelectromechanical ResonatorsHumad, Shweta 12 July 2004 (has links)
This thesis reports on the use of sputter-deposited zinc-oxide as a transduction mechanism to actuate and sense single crystal silicon (SCS) microelectromechanical (MEMS) resonators. Low frequency prototypes of piezo-on-silicon resonators with operating frequencies in the range of hundreds of kHz were implemented using micromechanical single crystal silicon clamped-clamped beam resonators. The resonators reported here extend the frequency of this technology into very high frequency (VHF range) by using in-plane length extensional bulk resonant modes. This thesis outlines the design, implementation and characterization of high-frequency single crystal silicon (SCS) block resonators with piezoelectric electromechanical transducers. The resonators are fabricated on 4m thick SOI substrates and use sputtered ZnO as the piezo material. The centrally supported block resonators operate in their first and higher order length extensional bulk modes with high quality factor (Q). Measurement results are in good agreement with the developed ANSYS simulations.
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