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Dissertations / Theses on the topic 'Bearing life'

Author: Grafiati
Published: 4 June 2021
Last updated: 17 February 2022

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1

Biboulet, Nans. "Influence of indentations on rolling bearing life." Phd thesis, INSA de Lyon, 2008. http://tel.archives-ouvertes.fr/tel-00663264.

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Les lubrifiants contiennent des particules qui sont à la fois initialement présentes dans le lubrifiant et dans le mécanisme (fabrication, stockage ) ; générées durant le rodage, par usure ou corrosion ; ou bien issues de sources externes. Les particules détériorent les surfaces en créant des indents lorsqu'elles sont piégées dans les contacts. Ces indents augmentent le risque de rupture par fatigue en induisant des perturbations de pression et de contraintes. Ce travail est basé sur une étude des contacts indentés secs et lubrifiés (EHD). L'équation de Reynolds en fluide Newtonien est utilisée. Les techniques mutigrilles et multi-intégration sont employées. L'objectif de ce travail est de proposer un modèle de prédiction des perturbations des champs de pression et de contraintes, et finalement un modèle de réduction de durée de vie des contacts indentés en fonction de la géométrie des indents et des conditions de contact.
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2

Riddle, Paul W. "Equipped to share : a curriculum for workplace evangelism /." Online full text .pdf document, available to Fuller patrons only, 2003. http://www.tren.com.

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3

Thompson, Jeffery Will. "A personal testimony workshop for the First Baptist Church of Chelsea, Oklahoma." Theological Research Exchange Network (TREN), 1996. http://www.tren.com.

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4

Marr, Carroll D. "Developing and implementing a lifestyle evangelism program with a select group of adult members of Zoar Baptist Church, Baton Rouge, Louisiana." Theological Research Exchange Network (TREN), 1997. http://www.tren.com.

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5

Miles, J. Matthew. "Developing a program of holistic evangelism for the First Baptist Church of Stillwater, Oklahoma." Online full text .pdf document, available to Fuller patrons only, 2001. http://www.tren.com.

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6

Rasiulis, Nicolas. "Freestyle Bearing: Work, Play, and Synergy in the Practice of Everyday Life Among Mongolian Reindeer Pastoralists." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34449.

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Approximately 200 people, mostly Dukhas of Tuvan ancestry, live nomadically with reindeer, horses, and dogs as ‘Tsaatans’ in the taiga of northern Mongolia. How do they effectively realize their livelihoods? Does qualifying corporeal manners, or bearings, in which livelihood practices are performed in the moments of actualization offer insight into ways in which longer-term decision-making processes like nomadic settlement and livestock management are embodied? Informed by a phenomenological approach in anthropology during nearly four months of cooperative co-habitation with Tsaatan mentors, I argue that Tsaatans effectively realize livelihood practices as they cheerfully embody poised improvisation and acrobatics in both skillful discernment and movement. Simultaneously anticipating and performing diverse tasks in playful cooperation with friends, family and other animals along nomadic lifestyles in a wilderness habitat involves persistent, sensory-rich, versatile manipulation of environmental materials, as well as extensive geographic knowledge and frequent experiences of risk in remote, rugged terrain and powerful meteorological conditions impossible to completely avoid. These lifestyles catalyze the development of quick-witted and materially sensitive resilience with which people are capable of corresponding with beings, materials, and situations, and thereby of continuing to develop ancestral traditions of reindeer husbandry in a rapidly changing social, economic, technological and geo-political context.
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7

Johnstone, Nicola. "How load bearing can influence cognitive performance : investigated using mobile electroencephalography (EEG) recordings in real-life settings." Thesis, University of Surrey, 2018. http://epubs.surrey.ac.uk/845540/.

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Physical load carriage is an essential duty for military personnel. Physical load carriage induces psychological and physiological effects, but the influence of load carriage on brain activity and subsequent cognitive performance is largely unknown. This due to difficulties in disentangling the subtle behavioural effects under load carriage in complex occupational settings. To investigate how load carriage influences cognition directly, continuous measures of brain activity must be obtained in realistic settings. Mobile EEG is ideally suited to this task. Across four studies, mobile EEG recordings were used to assess to what extent load carriage influences attention. Four objectives were defined. 1. To evaluate mobile EEG as a viable tool in real-life settings (studies 1-4). 2. Investigate the influence of walking on attentional processes (study 1, selective attention; study 2, change detection). 3. Establish the impact of load carriage on brain activity during walking (study 3). 4. Assess the interaction of load carriage on attentional processes during walking (study 4). Interpretations of resulting data were conceptualised in the proposed dynamic resource allocation model of cognitive performance. Successful application of Mobile EEG was evident and found signal quality comparable to EEG recorded in a laboratory. Moreover, walking influenced attentional processes in an indirect way, moderated by the environment and concurrent perceptual load. While a steady state neural index of walking was recorded in a natural setting, this was invulnerable to load carriage effects. Further, and most pressing for this thesis, load carriage had little influence on neural indices of attention. Despite this, there is some indication from the data that fatigue plays a prominent role in the interaction of load carriage and cognitive function, and further exploring the neural underpinnings of motivation may prove fruitful in future studies of load carriage and cognitive function.
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8

Hari, Rohit. "KNOWLEDGE DISCOVERY USING DATA ANALYSIS TECHNIQUES AND INVERSE EXTREME VALUE STATISTICS TO BETTER PREDICT LIFE OF A BEARING." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366304299.

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9

Kucukyilmaz, Ali. "Experimental Investigation Of Residual Stresses Introduced Via Shot Peening And Their Effect On Fatigue Life Of Ball Bearings." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/2/12611494/index.pdf.

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In this study, residual stresses introduced via application of shot peening on the raceways of bearing rings and their effect on the fatigue life was investigated experimentally. For improvement of residual compressive stress state, shot peening operation with different parameters was utilized. Residual stress measurements were conducted via X-ray diffraction technique. Optimization of residual stress state during the production of ball bearings is the main target of this study. Process parameters for shot peening and super-finishing were studied for determination of the parameters that induce the most favorable residual stress state. The fatigue life of ball bearings were determined by life cycle tests and tabulated to show the results of the study. The results of the thesis are believed to help for optimization of residual stress distribution and improvement of service life of ball bearings.
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10

Eroglu, Baris. "Inner Ring Fatigue Analysis Of Rolling Element Bearings." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12610421/index.pdf.

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Rolling element bearings are the one of the most widely used machine elements in the industry. The most important criterion in bearing selection is the endurance life. The first attempts on the prediction of the endurance life of rolling elements bearings are done by Lundberg and Palmgren in 1950s (Harris, 1999). Their work adopted as an ANSI, ABMA and ISO standard which is widely used in industry today. The basic assumption of Lundberg-Palmgren formulation is that no matter how small the load applied on rolling element bearing, all material in the stressed volume is subject to fatigue failure. In this study, four main life theories
Weibull, Lundberg-Palmgren, Ioannides-Harris, and Zaretsky on rolling element bearings have been investigated. Three-dimensional finite element models of a bearing&rsquo
s inner ring and rolling element have been prepared. The stress fields within the inner ring and the ball with respect to the applied load are obtained numerically. The fatigue life of the inner ring has been predicted by two methods that are widely used for fatigue analysis
Total Life Analysis (S-N method) and Crack Initiation Analysis (&
#56256
&
#56624
-N method). Obtained results are compared with ISO formulation. As a result of the investigation, S-N and &
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&
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-N methods are determined to give more conservative results than ISO method for higher loads that cause stresses above the fatigue limit of the material. The used methods for bearing life prediction recognize the existence of the fatigue limit stress. Hence as the stresses within an operating bearing do not exceed the limit stress, the bearing can achieve infinite life. It is also observed that load variation has a direct influence on the bearing life. When the load significantly changes from the levels which create stress above the fatigue limit to the levels that result stress is below the fatigue limit, the bearing would have higher endurance life than predicted by ISO method.
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11

Ammerman, Leah. "Quality of Life After Cardiac Valve Replacement Surgery." Honors in the Major Thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1200.

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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information.
Bachelors
Health and Public Affairs
Nursing
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12

Mitchell, Kevin G. "Equipping a volunteer group at First Baptist Church, Wolfe City, Texas, to develop "personal crisis testimonies" which express thanks to God for his faithfulness in providing strength for recovering from difficulties so that participants will use their experiences in comforting others who are hurting and witnessing to the lost /." Theological Research Exchange Network (TREN) Access this title online, 2005. http://www.tren.com.

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13

Siegel, David. "Evaluation of Health Assessment Techniques for Rotating Machinery." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1250282528.

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14

Hjerpe, Stefan. "Längdmätning i engreppsskördare." Thesis, Växjö University, School of Technology and Design, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-1534.

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Detta examensarbete har gjorts på uppdrag av SP Maskiner AB och berör längdmätningsenheten på skördaraggregatet SP451LF. Pulsgivaren i den befintliga längdmätningen anses inte nå en acceptabel livslängd och därför skall ett sensorlager prövas som ersättare.

Uppdraget består i att söka ett lämpligt sensorlager, dimensionera en komplett mäthjulslagring samt att ta fram ett konstruktionsförslag till prototyp på längdmätning.

Arbetet begränsas av att den omkonstruerade längdmätningen skall passa på SP451LF aggregatet. Det betyder att längdmätningens infästning mot aggregatet inte får förändras och dess yttermått måste hållas inom de gränser som aggregatets chassi tillåter.


This diploma work has been done on commission by SP Maskiner AB and affects the length meter unit on the single-grip harvester SP451LF. The pulse encoder in the present length meter has too short duration why a sensor-bearing will be tested as replacement.

The tasks are to find a suitable sensor-bearing unit, to dimension a complete measuring wheel bearing and create a construction proposal for a prototype of a length meter.

The diploma work is limited by the fact that the reworked length meter has to fit into the SP451LF harvester. That means that the length meter’s contact points on the harvester’s frame are not to be altered.

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15

Park, Ah-Hyung Alissa. "Carbon dioxide sequestration chemical and physical activation of aqueous carbonation of Mg-bearing minerals and pH swing process /." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1124272324.

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Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains xx, 176 p.; also includes graphics (some col.). Includes bibliographical references (p. 169-176). Available online via OhioLINK's ETD Center
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16

Lindvall, Erik. "“The purpose of life is finding the largest burden that you can bear and bearing it.” : A study of the making of meaning among Jordan Peterson supporters." Thesis, Uppsala universitet, Teologiska institutionen, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-377506.

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The aim of this thesis is to study, understand and explain the theories and work of the Canadian psychologist Jordan Peterson, whose controversial statements and lectures have made him a darling of certain factions of the political right, as he portrays himself as an enemy of progressive ideology. With a focus on understanding and explaining Peterson and how he provides meaning to his followers, the study will go through Peterson’s work in his two books Maps of Meaning and 12 Rules for Life in order to analyze their content and the follower’s reaction to the books as well as Peterson’s persona as a whole.   To analyze these works, hermeneutic methods based on the work of finnish theologian Björn Vikström will be utilized. The texts will be analyzed on a textual and intertextual level, but the role of the author as well as the readers will also be put under scrutiny in order to elaborate on many aspects of Peterson’s writing. To analyze how he provides meaning to his followers and the definition of the terms lifestance and meaning, the work of Swedish theologian Carl Reinhold Bråkenhielm will be referenced and compared to Peterson’s work.   While Vikström and Bråkenhielm will be the main sources of intertextual comparison with Jordan Peterson, they will also be supplemented with the work of other established theologians such as Hjalmar Sundén and others to further understand and compare the making of meaning undertaken by Jordan Peterson to other academic studies in the field of making meaning.
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17

Campanha, Marcos Vilodres. "Estudo sobre a vida útil de rolamentos fixos de uma carreira de esferas." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3151/tde-31032008-180633/.

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O presente trabalho destina-se à discussão sobre o cálculo de vida útil de rolamentos. Mostrando o avanço do processo de cálculo ao longo das décadas até o mais alto grau de desenvolvimento atual. A preocupação do texto é demonstrar de forma simples e objetiva as divergências que existem entre a formulação teórica e a real vida dos rolamentos, no que tange a fadiga de contato. Neste contexto foram realizados testes, em máquina especialmente destinada ao ensaio da fadiga de rolamentos. Variando-se para as duas séries de ensaios, apenas, a temperatura (aproximadamente 85°C e 110°C). Os resultados obtidos indicam que a vida real dos rolamentos apresenta grande divergência se comparada com a vida útil calculada, principalmente, no regime com maior temperatura. Atribui-se a esta disparidade, a ausência de cálculos precisos quanto à correlação da vida útil com o fator l, que é uma forma de se calcular o espaçamento entre as superfícies de contato, e o não emprego do cálculo do fator de carga, na formulação da vida útil de rolamentos.
The present work has the purpose of discussing the life of rolling bearings, describing the evolution of bearing life calculation until its current state of the art. Our focus is to demonstrate, simply and objectively, the inconsistencies occurring between the actual life of rolling bearings and their theoretical fatigue life estimation. For such purpose, tests were developed in a special bearing test rig to assess bearing fatigue. Two test sets were carried out with temperature being the only variation (approximately 85°C and 110°C). Results obtained from these tests suggest that the real life of rolling bearings is indeed very different from calculated bearing life, especially under higher temperature. Such disparity can be attributed to the lack of a precise computation of the relationship between bearing real life and the l factor - which determines the thickness of lubricant separating raceways and balls - as well as to the failure to compute the load factor in bearing life estimation.
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18

Vacula, Jan. "Jednoválcový čtyřdobý motor motokrosového motocyklu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-231761.

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This diploma thesis is focused on construction of one-cylinder four stroke engine designed for motocross competition. The target was create the 3D model, which has foundation on the thermodynamic simulation. Kinematics of timing mechanism was designed in Lotus Simulation. For checking the main bearings life calculation was performed.
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19

Prášilová, Alena. "Výzkum a vývoj ložisek pro trakční motory." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229429.

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This master’s thesis deals with construction design of cylindrical roller bearing for traction motor and design of life test tool for designed bearing. At the thesis beginning there is an overview of new trends in design of cylindrical roller bearing, according to new trends is designed a new construction design of cylindrical roller bearing. Other part of thesis is strain stress analysis, which assesses an optimal inclination of collar faces and optimal raceway modification of hybrid bearing rings. At the end life test will be analyzed.
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20

Froelich, Carey D. "Equipping Christians at University Baptist Church to use a dialogical model to foster spiritual growth among persons alienated from God." Online full text .pdf document, available to Fuller patrons only, 2002. http://www.tren.com.

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21

Mertz, David Hunter. "Lift-off performance in flexure pivot pad and hybrid bearings." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3197.

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22

Sajeva, Lisa. "Predizione del tempo rimanente di vita di un impianto mediante Hidden Markow Model." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13846/.

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In this thesis we investigate the main methods used in the literature for the automation of conditio-base maintenance and then see a pratical application concerning bearing system. In the specifics we first analyze the row signal of vibration decomposing whit a wavelet packet transform then, we select the best level and index in term of characteristics. For create a model of failure we use the method of Hidden Markov Model. At least we compare the model generated with other level and index of decomposition to demonstrate that our choice was the best.
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23

Zhang, Cheng. "Defect detection and life prediction of rolling element bearings." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/17658.

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24

Clements, Shaun. "On line vibration of a flexible rotor/bearing system." Thesis, University of Strathclyde, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302866.

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25

Buttress, Adam James. "Physicochemical behaviour of artificial lime stabilised sulfate bearing cohesive soils." Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/14463/.

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Soil stabilisation is a useful civil engineering technique that enables the insitu material to be used as part of an engineered structure. Stabilised layers are used in road foundation; working platforms and for slope stabilisation and sea defences. Chemical stabilisation involves the use of a hydraulic binder (and sometimes additional pozzolans). Commonly, quicklime (CaO) or slaked-lime (Ca(OH)2) is used. On mixing into the ground, this reacts with the aluminosilicates of the clay fraction, reducing its overall water content and plasticity. Further additions increase the insitu pH. Above pH 10.4, the aluminosilicates become soluble in the pore solution. They are then able to form a range of insoluble mineral hydrates which constitute a cementitious matrix. This results in both an increase in mechanical strength and a decrease in dimensional stability. If the insitu material contains sulfur bearing mineralogies, these can react with the hydraulic binder and the aluminosilicates to form expansive minerals. If this occurs after the initial setting and hardening of the stabilised layer has occurred, it can lead to severe dimensional instability and mechanical weakening. This is termed sulfate heave and the principal agent of this heave is a hydrous calcium sulfoaluminate hydrate, ettringite (AFt). The fundamental processes of ettringite formation and associated expansion are little understood in stabilised soils. This research used a range of artificial sulfate bearing, lime stabilised blended soil samples subject to two immersion tests used for material suitability assessment in the UK. The physicochemical response (in terms of dimensional heave and mechanical weakening) was assessed as a function of soil composition and the environmental conditions imposed by the two immersion tests. The fundamental microstructure and phase composition was characterised using a range of analytical techniques (XRD, SEM-EDX, dTGA). The relationship between the observed macro-physical properties and underlying chemical environment and microstructure was explored. Key findings include that the mechanism of ettringite formation and expansion was found to be governed by the fundamental structure of the bulk clay. This explained the greater swell response of the kaolin based soils compared to those of the montmorillonite. The SEM-EDX analysis identified a primitive, Ca-rich, AFt phase termed ‘ball ettringite’, in stabilised soils. This has only relatively recently been reported in studies of cement mortars. Also, small amounts of sulfate in the bulk soil actually increase soil strength. It was suggested that the preferential formation of monosulfate (AFm) plays an important role in this mechanism. The introduction of water to the pore solution is key to the formation of ettringite. This was evidenced by X-Ray CT of the damage caused to soil specimens on immersion, as well as low angle XRD studies of the principal AFt peak. Based on the limited testing undertaken one of the immersion tests (European accelerated volumetic swell test, EN13286-49), appears to be more onerous than the other (UK CBR linear swell test, BS1924-2).
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26

Cazan, Alfy Morales. "Maternal transfer of metals in live-bearing fish (Cyprinodontiformes| Poeciliinae)." Thesis, University of Louisiana at Lafayette, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3622929.

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This study assessed the occurrence and impacts of maternal metal transfer in live-bearing fish. The occurrence was investigated in two different species (Gambusia affinisand Heterandria formosa), while the impacts were studied only in G. affinis. Occurrence and impacts were addressed by exposing gravid females for 10 days to 0.15 μM of copper or cadmium, transferring the fish to clean water, monitoring their reproduction and collecting newborn offspring for further analyses of their health and reproductive success.

Maternal transfer of copper and cadmium occured in both study species. Metal levels decreased in subsequent broods and in broods born later after a female's exposure. Metal exposure impacted the reproductive success of exposed-females; effects included smaller broods and more broods were aborted broods or contained dead offspring. Many effects remained for second broods developing well after the exposure.

The maternal metal exposure also impacted the offspring's health. Newborn offspring were smaller at birth, had reduced calcium levels, had a lowered metal tolerance, and had cellular membrane damage. When these offspring grew up, they had an increased rate of malformations, a smaller size at sexual maturity, increased gestation time and fewer broods. In spite of the impacts on life history parameters found in the laboratory, effects on population dynamics were very limited for greenhouse mesocosm populations established with the offspring of exposed females.

Effects for the essential metal (copper) and the nonessential metal (cadmium) were generally similar. A few effects, like those on body size, were evident for copper but not for cadmium. However, several of the more severe impacts, like the increase in malformations and reductions in the number of broods, were greatest for the offspring of the cadmium-exposed females.

This is the first report demonstrating negative impacts resulting from a short-term maternal metal exposure in live-bearing fishes. Effects were evident not just for reproduction of exposed-females but also for their offspring's health and reproduction. The latter continued beyond the offspring that were developing during exposure. This study demonstrated that the internal development in live-bearing fish may not spare the developing young from impacts caused by a metal-contaminated environment.

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27

Vaculka, Miroslav. "Návrh metodiky výpočtu životnosti valivého ložiska." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241927.

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This master’s thesis deals with a fatigue analysis of a roller bearing. The fatigue analysis consists of determining service-life of a roller bearing using a stress-strain analysis with finite element method and subsequent numeric calculation using software fe-safe with application of Brown-Miller multiaxial fatigue criterion. Service-life of a roller bearing is determined by number of cycles to failure in the form of pitting formation which is consequence of contact fatigue. According to calculations was found an inappropriateness of Brown-Miller criterion for high-cycle contact fatigue. Test of other available criteria was performed. Principal-Strain criterion provided the best match with ISO 281 standard.
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28

Jackson, Latonya. "The Effects of 17alpha-ethinylestradiol in the Live-Bearing Fish Heterandria formosa." Thesis, University of Louisiana at Lafayette, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10163310.

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This study assed the impacts of 17α-ethinylestradiol in Heterandria formosa. These impacts were addressed through chronic, life-cycle exposures of individuals and populations of least killifish to 0, 5, or 25ng/L EE2. Development, growth, reproduction, survival, and population dynamics were monitored and evaluated for EE2 effects on their health, reproductive success, and population sustainability.

Exposing pairs of least killifish to EE2 resulted in similar increases in time-to-sexual maturity for both sexes. The EE2-exposure had a sex-dependent effect on body size, with standard lengths and wet weights of females significantly reduced and standard lengths of males markedly increased. Offspring production decreased by 50% and 75% for fish exposed to 5 and 25ng/L EE2 respectively. Sexual development was even further delayed in EE2-exposed offspring of exposed fish. EE2-exposure also affected the gonadal and liver development in least killifish. Males exposed to EE2 had delayed sperm maturation and severe intersex (a phenomenon in which eggs and sperm are produced within the same male). These effects were more severe at the 5ng/L than at the 25ng/L EE2 concentration. Exposing females to EE2 resulted in delayed egg maturation. Furthermore, EE2 exposure resulted in changes in liver morphology in both males and females. For both the delay in egg maturation and the changes in liver morphology, the effects were strongest at the higher EE2 concentration.

Effects of chronic EE2-exposure on populations were assessed at the 5ng/L concentration. EE2-exposure caused significant reductions in population size and population growth rates, and caused other changes in population dynamics. Exposed populations had a pronounced female-biased sex ratio and significantly reduced abundances of males and newborns. These responses were observed within one breeding season.

This is the first report demonstrating a variety of negative impacts resulting from chronic EE2-exposure in least killifish at both the individual and population levels. Effects were evident in all stages of development and in all life history stages. This study demonstrated that, similar to the case for other fish, live-bearing fish are likely to be severely affected when their environment becomes contaminated by EE2 and that steps are needed to prevent exposure to this endocrine disrupting chemical.

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29

Jennings, Emily C. "A Holobiont Characterization of Reproduction in a Live-bearing Cockroach, Diploptera punctata." University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1554215396831703.

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30

Craig, Mark. "Advanced condition monitoring to predict rolling element bearing wear using multiple in-line and off-line sensing." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/185079/.

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31

Rachamalla, Vishnu V. "A model of stabilizer roll bearing for a continuous hot-dip galvanizing line." Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4948.

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Thesis (M.S.)--West Virginia University, 2006.
Title from document title page. Document formatted into pages; contains x, 82 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 74-75).
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32

Cartwright, Sarah A. "The effect of surface, wheel, and bearing type on the physiological response of in-line skating /." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68077.

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The purpose of this study was to determine the physiological response of an in-line submaximal skate on two surfaces using two wheel types and two bearing types. The variables measured were V0$ sb2$ and HR. Ten male varsity hockey players volunteered as subjects. The subjects, after being assigned one of two wheel types with varying durometers, skated the submaximal test twice for each surface (concrete and asphalt) using a different type of bearing (precision and semi-precision) each time. These results were compared to a similar on-ice submaximal skating test session.
Results revealed no significant difference between in-line skating with wheels of 78 and 82 Shore A durometers (p $<$.05) with both V0$ sb2$ and HR as markers. A significant difference was found between in-line skating with precision and semi-precision bearings with V0$ sb2$ as a marker (p $<$.05), however, not with HR as a marker (p = 0.31). On-ice skating was significantly different from in-line skating on concrete and asphalt surfaces for both physiological markers. In-line skating on asphalt and concrete surfaces resulted in similar physiological responses. It was concluded that hockey players training with in-line skates obtain the same training benefits using either wheel durometers, but will have greater oxygen costs when training with semi-precision bearings than training with precision bearings.
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33

Lee, Wey-Jen. "Behavior of Connection with Beam Bearing on Bottom Flange of Girder." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/35529.

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An analytical investigation was conducted to study the behavior of a bottom flange bearing beam-to girder connection subjected to patch loading. This connection would be useful with deep deck (thickness greater than 3 in.) composite slabs as well as with commonly used deck where floor-to-floor height needs to be minimized. Five girder specimens were loaded until yielding during the initial phase of the research. The analysis section consists of the yield line theory and finite element study that were used to develop a model to predict the collapse loads of the girder sections. These results from the model were then compared to the experimental loads. A design procedure utilizing the proposed model and future work recommendations are then presented.
Master of Science
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34

Mohn, Douglas M. "Impact of Gypsum Bearing Water On Soil Subgrades Stabilized With Lime or Portland Cement." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1430836216.

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35

Vosper, Hayley. "Modelling of flow in air-riding bearings with lift generating features." Thesis, University of Nottingham, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.718987.

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Air-riding thrust bearings are comprised of a solid, annular rotor and stator in relative rotational motion separated by a thin air film, often with a pressure difference across the annulus. Lift-generating features may be in the form of geometric structures added to the surface of the rotor/stator and are designed to enhance the dynamic properties of the fluid film and increase the efficiency of the bearing. This thesis is focussed on modelling the air film in air-riding bearings and the effects of lift-generating features on the dynamic performance. A review of the relevant literature highlighted a lack of current models incorporating fully periodic boundary conditions and a limited understanding of flow near abrupt geometrical features such as steps. A local analysis was undertaken at a geometric step in an axisymmetric bearing, and matched asymptotically to a classical Reynolds equation based flow model. The effects of the step were measured to first order and gave justification to a widely used patching method. The asymptotic analysis was extended to azimuthal step orientations and yielded similar results. The steady Reynolds equation was solved with fully periodic boundary conditions for a range of bearing geometries and both incompressible/compressible flow models. Analytical methods were used where available and a verified finite element method was implemented using Matlab. Extensive results in the form of pressure and streamline plots were presented alongside key bearing quantities for a range of parameters. The motion of flexible lift-generating features in the form of rigid, hinged pads was coupled with a transient flow model and subjected to periodic axial oscillations of the rotor. The dynamic response of the fluid and pads was calculated and displayed for a range of relevant flow quantities. The numerical models in this thesis are also valuable for optimization of bearing geometry and related parameters.
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36

Huq, Fazul, and dpmeng@bigpond com. "Development of Life Prediction Models for Rolling Contact Wear in Ceramic and Steel Ball Bearings." RMIT University. Aerospace, Mechanical and Manufacturing Engineering, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080215.145624.

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The potential for significant performance increases, using ceramic materials in un-lubricated rolling element bearing applications, has been the subject of research over the past two decades. Practical advantages over steel include increased ability to withstand high loads, severe environments and high speeds. However, widespread acceptance has been limited by the inability to predict wear life for ceramic bearing applications. In this thesis, the rolling contact wear of 52100 bearing steel and Over-aged Magnesia-Partially-Stabilised Zirconia (OA-Mg-PSZ) ceramic are examined using a newly developed rolling contact wear test rig. The new wear test rig simulates the system geometry of an un-lubricated hybrid (ceramic and steel) ball bearing. The new wear test rig is versatile in that it allows low cost samples to be utilised resulting in a larger number of samples that can be tested. Wear samples of 52100 bearing steel and OA-Mg-PSZ produced by the new wear test rig were examined for mass loss and wear depth. The wear behavior of both the steel and ceramic material showed a dependence on operating variables time and load. Load was varied between 300N to 790N. Typical mass loss after 1 hour of testing 52100 bearing steel at 790N was 0.03 grams as compared to OA-Mg-PSZ which was 0.001 grams. The rolling contact wear of the OA-Mg-PSZ was an order of magnitude lower than that of the 52100 bearing steel. The wear mechanism for 52100 bearing steel was typical of plastic deformation and shearing near and below the surface of rolling contact. Once cracks extend to reach the surface, thin flat like sheets are produced. In OA-Mg-PSZ the wear mechanism initially is that of plastic deformation on the scale of the surface asperities with asperity polishing occurring followed by lateral cracks and fatigue spallation. Results obtained using the new rolling contact wear test rig led to the establishment of a new equation for wear modeling of 52100 bearing steel and OA-Mg-PSZ ceramic materials.
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37

Shiroishi, Jason William. "Bearing condition diagnostics via multiple sensors using the high frequency resonance technique with adaptive line enhancer." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/17779.

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38

Duran, Heriberto C. "ASSESSMENT OF LIVE LOAD DEFLECTIONS IN A SIMPLE SPAN COMPOSITE BRIGDE WITH PRESTRESSED PRECAST CONCRETE GIRDERS." OpenSIUC, 2016. https://opensiuc.lib.siu.edu/theses/1862.

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The purpose of this study is to investigate how accurately the distribution factor method estimates the live load deflections under the principles of the 2012 AASHTO LRFD Bridge Design Specifications (AASHTO LRFD specifications) compared to the results of the NISA finite element analysis software. The simple span bridge model analyzed is developed very similarly to the design example of the PCI Bridge Design Manual. The main difference is a shorter span length and smaller AASHTO-PCI bulb tee sections. Three main finite element models are created to estimate the live load deflections under the recommended live load conditions as per AASHTO LRFD specifications. The first model is simulated with simple support conditions. The purpose of this model is two-fold: compare the deflections to the distribution factor method and to the deflections of the second model that is simulated with elastomeric steel reinforced bearing pads. Thus, the stiffnesses of the elastomeric bearing pads of the second model are varied within the AASHTO LRFD specifications acceptable limits and under low temperature conditions the stiffness is increased accordingly for two cases. The purpose is to investigate if the stiffness have any significant affect on the deflections of the girders. Then a third model is created to investigate if the removal of the intermediate diaphragms have any affect on the deflections. The results of the first and second models, including the models with the allowed varied stiffnesses of the bearing pads, found only the interior girders deflecting up to 4% more and the exterior girders were deflecting up to 5.55% less than the estimates of the distribution factor method. In the case when the diaphragms are removed, the deflections of the inner most interior girders are deflecting up to 10.85% more compared to the same girders of the model which includes the intermediate diaphragms and the bearing pads. In the unique case of the second model where the bearing pads may stiffen significantly under low temperatures, the girders are deflecting up to 23% less than when at room temperature conditions. All these findings and other summarized results are discussed in greater detail in this study.
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39

Veith, Gabriele Helene. "Engineering properties of sulphate-bearing clay soils stabilised with lime-activated ground granulated blast furnace slag (GGBS)." Thesis, University of South Wales, 2000. https://pure.southwales.ac.uk/en/studentthesis/engineering-properties-of-sulphatebearing-clay-soils-stabilised-with-limeactivated-ground-granulated-blast-furnace-slag-gcbs(65f3da02-94cc-4db6-887c-8d94bead65b4).html.

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This research studied the effects of the addition of ground granulated blast furnace slag (ggbs), activated by 2% calcium hydroxide (Ca(OHh, on the strength, permeability and porosity development of a laboratory prepared clay mix (kaolinite with and without 6% gypsum) and a natural sulphide-bearing clay soil, Lower Oxford Clay. Based on shear, compressive and indirect tensile strength testing, it was found that an increase in the stabiliser slag/lime ratio results in substantial strength increase even after short curing periods (up to 12 weeks). This increase in strength is more pronounced if curing is at elevated temperatures (30 °C). The presence of sulphates (6% gypsum=2.73% SO3) resulted in an accelerated increase in the strength development for stabilised kaolinite, which was comparable to that of stabilised Lower Oxford Clay. In the absence of sulphates, large ggbs additions were only activated effectively at higher curing temperatures (20 and 30 °C) after curing periods of 24 weeks and beyond, although it is suggested that 2% lime creates a sufficiently alkaline environment for activation. The degree of slag activation and thus the subsequent cementation process was reflected by an increase in the percentage of the pore volume occupied by pores with a radius ::s;0.0Sμm, which is usually associated with the pore fraction characteristic of cementitious gels. The increase in slag addition, for kaolinite mixes, was accompanied by a reduction in total porosity. Specimens made from Lower Oxford Clay exhibited a significant increase in pore volume at higher slag additions. This is interpreted as being due to the creation of pore space resulting from restrained shrinkage of gels by inert particles during drying in this coarser, natural clay. No significant trend in the effect of curing temperature on the pore size distribution could be identified from the data. The development of permeability, however, showed some sensitivity to curing temperature. Results from specimens cured at 20 and 30 °C showed an accelerated reduction in their k-values in comparison to samples which had been cured at 10 °C. However, little correlation between measured permeability and exhibited pore size distribution could be established which is believed to be due to the strong influence of shrinkage during drying prior to mercury intrusion porosimetry in the dimensionally semi-stable soil system. The volume stability of stabilised specimens during frost action was assessed in a series of 12 freeze-thaw cycles, which were carried out in accordance to the German proposal for a European Pre-Standard. Generally an increase in the curing period prior to frost action and higher overall sample porosity resulted in relatively better performance during frost action. The influence of the slag/lime and slag/gypsum ratio on the swelling potential upon soaking was assessed in long-term soaking tests and the underlying causes were identified by findings from microstructural investigations including SEM and TG analysis. These results contributed to a better understanding of the slag activation process. In an alkaline environment slag hydration appears to be triggered earlier by sulphate, due to the more intensive disturbance of a thin protective layer of cementitious products on the slag grains. Disruption of this layer, for example by ettringite formation, exposes more unreacted slag grain surface, which will subsequently start to hydrate. Findings were complemented by two case studies, one which investigated the cause of substantial heave on a German highway on a microscale and the other which assessed the technical performance and the economic implications of a full-scale trial utilising the stabilisation technique with lime and ggbs for a temporary diversion. The overall findings from the projects indicate that soil stabilisation with lime and ggbs is, particularly for soils with significant sulphate/sulphide content, a feasible and environmentally friendly alternative to the classic soil stabilisation methods.
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40

Gong, Yu. "The mechanical properties and microstructures of vanadium bearing high strength dual phase steels processed with continuous galvanizing line simulations." Thesis, University of Pittsburgh, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10075903.

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For galvanized or galvannealed steels to be commercially successful, they must exhibit several attributes: (i) easy and inexpensive processing in the hot mill, cold mill and on the coating line, (ii) high strength with good formability and spot weldability, and (iii) good corrosion resistance. At the beginning of this thesis, compositions with a common base but containing various additions of V or Nb with or without high N were designed and subjected to Gleeble simulations of different galvanizing(GI), galvannealing(GA) and supercooling processing. The results revealed the phase balance was strongly influenced by the different microalloying additions, while the strengths of each phase were somewhat less affected. Our research revealed that the amount of austenite formed during intercritical annealing can be strongly influenced by the annealing temperature and the pre-annealing conditions of the hot band (coiling temperature) and cold band (% cold reduction). In the late part of this thesis, the base composition was a low carbon steel which would exhibit good spot weldability. To this steel were added two levels of Cr and Mo for strengthening the ferrite and increasing the hardenability of intercritically formed austenite. Also, these steels were produced with and without the addition of vanadium in an effort to further increase the strength. Since earlier studies revealed a relationship between the nature of the starting cold rolled microstructure and the response to CGL processing, the variables of hot band coiling temperature and level of cold reduction prior to annealing were also studied. Finally, in an effort to increase strength and ductility of both the final sheet (general formability) and the sheared edges of cold punched holes (local formability), a new thermal path was developed that replaced the conventional GI ferrite-martensite microstructure with a new ferrite-martensite-tempered martensite and retained austenite microstructure. The new microstructure exhibited a somewhat lower strength but much high general and local formabilities. In this thesis, both the physical and mechanical metallurgy of these steels and processes will be discussed. This research has shown that simple compositions and processes can result in DP steels with so-called Generation III properties.

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41

Murbach, Junior Eduardo [UNESP]. "Avaliação de Ciclo de Vida em processo de fabricação de rolamentos." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/138119.

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Este trabalho se propôs a realizar Avaliação de Ciclo de Vida em Processo de Fabricação de Rolamento de Agulhas, com intuito de identificar impacto ambiental nas etapas do processo de fabricação para eventual direcionamento de ações de melhorias em ternos ambientais, produtivos, e a título informativo. Foram mapeados processos de fabricação dos componentes do rolamento: anel interno, gaiola plástica de agulhas, agulhas e montagem. Os processos de fabricação apresentaram impactos ambientais nas categorias de combustíveis fósseis, respiráveis inorgânicos, alterações no clima, uso da terra, carcinogênicos, acidificação, ecotoxicidade e minerais, utilizando-se software SimaPro® e o método Eco-Indicator 99. Houve a identificação dos impactos ambientais provenientes de cada etapa do processo de fabricação de forma individual e global.
This scientific research offered to perform Life Cycle Assessment in Needles Bearing Process Manufacturing, with focus to identify environmental impacts in process manufacturing steps to eventual guidance of environmentally improvements actions, productivity, and informative notice as well. Manufacturing process components’ were identified inner ring, plastic cage, needles. The manufacture process presents environmental impacts in categories of fossil fuels, inorganic respirable, climate change, land use, carcinogens, acidification, ecotoxicity, minerals, according to software SimaPro® and method Eco-Indicator 99. The environmental impacts were identified concern to each manufacture process steps as individual and global conception.
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42

Sharma, Rajnikant. "Bearing-Only Cooperative-Localization and Path-Planning of Ground and Aerial Robots." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2884.

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In this dissertation, we focus on two fundamental problems related to the navigation of ground robots and small Unmanned Aerial Vehicle (UAVs): cooperative localization and path planning. The theme running through in all of the work is the use of bearing only sensors, with a focus on monocular video cameras mounted on ground robots and UAVs. To begin with, we derive the conditions for the complete observability of the bearing-only cooperative localization problem. The key element of this analysis is the Relative Position Measurement Graph (RPMG). The nodes of an RPMG represent vehicle states and the edges represent bearing measurements between nodes. We show that graph theoretic properties like the connectivity and the existence of a path between two nodes can be used to explain the observability of the system. We obtain the maximum rank of the observability matrix without global information and derive conditions under which the maximum rank can be achieved. Furthermore, we show that for the complete observability, all of the nodes in the graph must have a path to at least two different landmarks of known location. The complete observability can also be obtained without landmarks if the RPMG is connected and at least one of the robots has a sensor which can measure its global pose, for example a GPS receiver. We validate these conditions by simulation and experimental results. The theoretical conditions to attain complete observability in a localization system is an important step towards reliable and efficient design of localization and path planning algorithms. With such conditions, a designer does not need to resort to exhaustive simulations and/or experimentation to verify whether a given selection of a control strategy, topology of the sensor network, and sensor measurements meets the observability requirements of the system. In turn, this leads to decreased requirements of time, cost, and effort for designing a localization algorithms. We use these observability conditions to develop a technique, for camera equipped UAVs, to cooperatively geo-localize a ground target in an urban terrain. We show that the bearing-only cooperative geo-localization technique overcomes the limitation of requiring a low-flying UAV to maintain line-of-sight while flying high enough to maintain GPS lock. We design a distributed path planning algorithm using receding horizon control that improves the localization accuracy of the target and of all of the UAVs while satisfying the observability conditions. Next, we use the observability analysis to explicitly design an active local path planning algorithm for UAVs. The algorithm minimizes the uncertainties in the time-to-collision (TTC) and bearing estimates while simultaneously avoiding obstacles. Using observability analysis we show that maximizing the observability and collision avoidance are complementary tasks. We provide sufficient conditions of the environment which maximizes the chances obstacle avoidance and UAV reaching the goal. Finally, we develop a reactive path planner for UAVs using sliding mode control such that it does not require range from the obstacle, and uses bearing to obstacle to avoid cylindrical obstacles and follow straight and curved walls. The reactive guidance strategy is fast, computationally inexpensive, and guarantees collision avoidance.
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43

Du, Preez Rudolph C. "Effect of lime additions and bulk chromium content on chromium deportment in smelter matte-slag systems." Thesis, Stellenbosch : Stellenbosch University, 2010. http://hdl.handle.net/10019.1/17459.

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Thesis (MScEng) –Stellenbosch University, 2010
ENGLISH ABSTRACT: More mining houses are turning their attention to the processing of ore mined from the UG2 reef. This is mainly due to the depletion of the Merensky reef or the low availability of ore from the Platreef. With the higher UG2 ore concentration in the process feed, companies experience more problems with the processing of the ore due to its high chrome content. Although there are various possible solutions to the problems experienced in the processing of UG2 ore, very little of thise solutions are actually implemented in the industry. When smelting chrome-bearing ore, the chrome can go to any of three phases: matte phase, spinel phase or glass phase. If it reports to the furnace matte phase it can lead to problems in the down stream processing. When chrome forms part of the spinel phase it forms a solid, refractory-like material which, to an extent, is an unwanted material inside the furnace. Lastly the chrome can report to the glass phase (liquid phase) which is the more desireable phase to which chrome should report to since it will have little or no impact on downstream processing. There were four main objectives for this research project namely to conduct a literature review to understand the problem of chrome in the smelting process, to do an experimental simulation of a matte and slag phase in one crucible, to interpret the experimental results and compare the experimental results to thermodynamic predictions obtained using FactSageTM. From literature the following aspects were found to be important: Silica structures Research has shown that silica incorporates different metal ions into its structures. When the metal ions are incorporated into the silica structures they are seen as part of the glass phase. By incorporating cations such as chromium into the silica structure the structure is able to maintain its neutral electrical charge. Basicity of slag Oxides once melted will either donate or accept oxide ions. The group of oxides that are in excess will determine whether that specific slag is acidic or non acidic. This is important to our study since the basicity can determine the stability of the spinel phase. Partial pressures The partial pressure of the system is important since it forms part of the equilibrium constant calculations - meaning that partial pressures determine the stability of certain species. Currently different arguments exist as to how the sulphur pressure inside a molten bath is maintained. What is important, however, is that for the system in this research project a log oxygen partial pressure of -8 and a log sulphur partial pressure of -3.5 was chosen. These values were based on previous research done on PGM and copper smelting processes. Chrome deportment Previous research on chrome deportment shows a relationship between temperature and the amount of chromium dissolving into the glass phase as well as an increased chromium(II)oxide solubility (when compared to chromium(III)oxide) in a silicate melt. Regarding slag chemistry and chrome deportment very little work has been published for the system found in the PGM industry but it is mentioned that by adjusting certain slag additives (alumina, lime and silica) the chrome deportment can be manipulated. The scope of this project was to investigate the effect of chromium, lime and silica on chrome deportment. More specifically, the effect of lime. The reason being that lime was originally added as 10%wt of the feed stream in the processing of Merensky ore to act as a fluxing agent. With the new furnace design and higher power densities the slag are maintained at 200oC to 350oC higher than when Merensky ore was smelted. With these higher slag temperatures fluxing agents will play a smaller role meaning that lime additions become less important. Literature studies also showed that additional lime in a slag system can stabilize the spinel structure (which is an unwanted phase). Removing lime would be advantageous out of a chrome presepective as well as an economic point of view. The research was conducted in three sections namely the determination of the time required for this particular system to reach equilibrium, the investigation of different additives on chrome deportment using a controlled atmosphere and synthetic slags and, lastly, a comparison of the experimental results obtained to thermodynamic predictions. For the equilibration studies reaction time periods of 4,7,11 and 16 hours were used. From the results it was found that the alumina crucible dissolved into the glass phase continually. This indicated that equilibrium was not reached. However, a reaction time, rather than an equilibrium time, was chosen where the species and phases had enough time to react. This was based on literature, on observations of species diffusing between the matte and slag phase as well as on two-point analysis (diffusion gradients). A reaction time of nine hours was chosen With the reaction time fixed, the effect of different slag additives on chrome deportment was investigated. For the addition of chrome it was seen that an 1.5%wt increase in the starting material increased the chrome content of the slag phase by 0.025%wt. For the same increase in chromium in the starting materials the chrome content of the spinel phase increased by 2.1% indicating that chromium has a tendency to report to the spinel phase. The increase in chromium had a minor effect on the chrome content of the matte phase, however, since the chrome content only increased from 0.025%wt to 0.028%wt. Plotting the results showed that increasing the lime in the starting material decreases the chromium content in the glass phase. For the 39%wt silica system the chromium content in the glass phase decreased from 0.75%wt to 0.46%wt for an increase in the lime content from 1.7%wt to 7.3%wt. The same trend was seen for the 33%wt silica system. For the spinel phase an increase of 1.27%wt was seen when the lime content of the starting materials was increased from 1.7%wt to 10.1%wt for a 33%wt silica system. The same increase in lime increased the chrome content of the matte phase from 0.03%wt to 0.06%wt for a 33%wt silica system. Silica also proved to affect chrome deportment. Increasing the silica content of the starting materials from 25%wt to 39%wt increased the amount of chromium in the glass phase from 0%wt to 0.46%wt for a 10%wt lime system. The same effect is seen for a lower lime content except that more chromium were incorporated into the silica structure. A silica increase from 32.4%wt to 39%wt resulted in a chromium decrease from 5.2%wt to 0% in the spinel phase for a 10%wt lime system. The same trend was seen for the 1.5%wt lime system. An increase in the silica levels lead to an increase in the chrome level of the matte phase. When silica is increased from 32%wt to 39%wt the chrome content of the matte phase increased from 0.06%wt to 0.07%wt. The last part of the research project entailed the comparison of the trends observed with the experimental results to trends obtained from thermodynamic predictions. FactSageTM is a program that uses model equations to predict the Gibbs free energies for different phases. The program is therefore also able to predict the amount of different phases present at equilibrium. This is called thermodynamic ”optimization”. In section 6 trends that were observed from FactSageTM results are compared to the trends found in the experimental results. It is important to note that it is only trends that are evaluated and not actual values since FactSageTM calculations are for a system that is at equilibrium and (as explained above) this system is not at complete equilibrium. The comparison however was good. Several trends found in the experimental results were confirmed by the results from FactSageTM. These included the relationships of chromium fed versus chromium spinel, lime fed versus chromium spinel, lime fed versus chromium in glass, silica fed versus chromium in glass, silica fed versus chromium in spinel and silica fed versus chromium in matte. To conclude, slag additions can be used to manipulate chrome deportment to an extent. Secondly, FactSageTM can be used for thermodynamic predictions but a proper understanding as well as some form of validation of the specific system investigated is still needed. Due to time constraints and the difficulty of experimentally simulating this multi-phase system in the lab, only a few parameters were investigated. In order to obtain a more complete understanding of the system the effect of partial pressures and temperature should also be investigated.
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44

Igue, Roberto T. "Experimental Investigation of a lift augmented ground effect platform." Wright-Patterson AFB, OH : Air Force Institute of Technology, 2005. http://handle.dtic.mil/100.2/ADA440437.

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45

Weinberger, Andreas. "Systèmes modèles de membranes et potentiel de pénétration de polypeptides." Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-01065966.

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Les vésicules géantes unilamellaires (GUV) permettent d'étudier efficacement les interactions entre les lipides et les peptides. Dans ce manuscrit, il a été montré que les interactions attractives lipides-peptides sont supprimées par l'attachement de polypeptides de type élastine (ELP) sur des peptides riches en arginine et peuvent être modulées par l'auto-assemblage en micelles ainsi que par le nombre de groupements arginine dans la séquence des peptides capables de pénétrer les cellules. De plus, une nouvelle méthode pour former des GUV à partir de systèmes complexes en seulement quelques minutes a été développée. Cette méthode est basée sur le gonflement d'un film de PVA sous une bicouche lipidique. Elle supprime la dégradation des molécules pendant la formation des GUV de lipides synthétiques, tels que des glycolipides et des phospholipides portant des groupements amides, où les méthodes traditionnelles ne réussissent pas à produire des vésicules non endommagées.
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46

Collins, William Norfleet. "Live Load Testing and Analysis of the Southbound Span of U.S. Route 15 over Interstate-66." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/34364.

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As aging bridges around the United States begin to near the end of their service lives, more funding must be allocated for their rehabilitation or replacement. The Federal Highway Administrationâ s (FHWA) Long-Term Bridge Performance (LTBP) Program has been developed to help bridge stakeholders make the best decisions concerning the allocation of these funds. This is done through the use of high quality data obtained through numerous testing processes. As part of the LTBP Pilot Program, researchers have performed live load tests on the U.S. Route 15 Southbound bridge over Interstate-66. The main performance and behavior characteristics focused on are service strain and deflection, wheel load distribution, dynamic load allowance, and rotational behavior of bridge bearings. Data from this test will be used as a tool in developing and refining a plan for long-term bridge monitoring. This includes identifying the primarily loaded girders and their expected range of response under ambient traffic conditions. Information obtained from this test will also aid in the refinement of finite element models by offering insight into the performance of individual bridge components, as well as overall global behavior. Finally, the methods and results of this test have been documented to allow for comparison with future testing of this bridge, which will yield information concerning the changes in bridge behavior over time.
Master of Science
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47

Hall, Charles. "Ex vivo reprogramming of tumor-reactive immune cells from FVBN202 mice bearing lung metastatic mammary carcinoma: an immunotherapeutic opportunity revealed against recurrence." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/3176.

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Metastatic breast cancer treatment has seen few advances in recent years, yet treatment resistance continues to rise, causing disease recurrence. A pilot study was performed to determine the efficacy of ex vivo expansion and reprogramming of tumor-reactive immune cells from experimental metastatic tumor-sensitized mice. Also, phenotypic changes in tumors due to metastasis or tumor microenvironment influences were characterized. Metastatic neu+ mouse mammary carcinoma (mMMC) and its distant relapsing neu-antigen-negative variant (mANV) were investigated in FVBN202 mice. Tumor-reactive central memory CD8+ T cells and activated NK/NKT cells were successfully reprogrammed and expanded during 6-day expansion from mMMC- and/or mANV-sensitized mice, resulting in tumor-specific cytotoxicity. mMMC exhibited a flexible neu-expression pattern and acquired stem-like, tumorigenic phenotype following metastasis while mANV remained stable except decreased tumorigenicity. Myeloid-derived suppressor cell (MDSC) levels were not increased. Adoptive cellular therapy (ACT) with reprogrammed tumor-reactive immune cells may prove effective prophylaxis against metastatic or recurrent breast cancer.
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48

Li, Kai. "Collapse Experiments and Assessment of Masonry Wall Buildings." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1503265342241364.

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49

Beyer, Thibault. "Semi-analytical modeling of damage under contact loading : Application to heterogeneous materials." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI045/document.

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Les pieds d’aubes de soufflantes de turboréacteurs étant soumis à des sollicitations de type fretting, l’introduction de matériaux composites dans la nouvelle génération de moteur d’avion a rendu nécessaire le développement d’outils permettant de modéliser le contact entre des matériaux hétérogènes. En particulier, le comportement tribologique et l’endommagement de ces matériaux est encore mal compris. La mise en place de méthodes numériques capable de prédire les endommagements dans le contact permettrait de mieux prédire la durée de vie des pièces en service et de garantir la sécurité des passagers. Cette thèse porte sur le développement de méthodes semi-analytiques pour la modélisation de l’endommagement dans des conditions de fretting et de roulement
The blade/disk interface in turbofan is subject to fretting loading. Fan blade of the new generation of aircraft engines are made of woven composite materials. The introduction of these new kind of materials create the need for a new numerical tool able to simulate the contact between heterogeneous materials. The tribological behavior and the damage mechanism associated with these kind of material are still not well understood. The developpment of new numerical tool able to model the damage in the contact area would allow to predict the life of engines parts and to guarantee the security of passengers. This PhD is about the developpment of semi-analytical methods for modeling the damage in fretting and rolling contact conditions with some applications to heterogeneous materials
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50

Medard, Fabien. "Contribution à la modélisation prédictive des comportements hautes fréquences des moteurs de traction." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAT029/document.

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La diminution drastique des temps de commutation des convertisseurs MLI, due aux technologies émergentes comme le SiC (Carbure de Silicium), engendre un nombre important de phénomènes hautes fréquences dans les moteurs électriques notamment des tensions inter-spires et des courants de paliers. Ces travaux portent sur l'établissement d'un modèle impédant prédictif, valable sur une large bande de fréquence, fournissant les valeurs des tensions et des courants dangereux pour les moteurs. Pour cela, une maquette à échelle réduite a été étudiée dans un premier temps pour comprendre les phénomènes et offrir un cas simplifié de modélisation. Un bobinage en circuit imprimé a été fabriqué à cet effet. Un modèle de ligne a été développé et offre des résultats satisfaisants en prenant en compte les effets dus à la montée en fréquence. La même démarche de modélisation a été adoptée dans le cas du moteur réel dans la suite des travaux. Des campagnes de mesures sur un moteur instrumenté ont permis d'observer la propagation des ondes dans le bobinage. Une bobine a également été instrumentée pour offrir un accès au potentiel de chaque spire. Un modèle présenté dans la littérature a été approfondi en proposant une méthode d'identification des paramètres à partir de quelques points de mesures. Ce modèle sert de comparaison avec le modèle prédictif établi à la fin de ces travaux. La dernière partie de ces travaux s'intéresse à la modélisation du même moteur de traction. Un modèle de ligne dont les valeurs de paramètres ont été issues de calculs analytiques ou de simulations numériques a été réalisé tout en évitant d'avoir recours à des mesures. Ce modèle a donc un comportement prédictif puisque les données d'entrées sont pour la plus grande majorité uniquement géométriques. Il donne accès aux valeurs de tensions dans le bobinage et à l'amplitude des éventuels courants de paliers. Ce modèle peut alors servir d'outil d'aide à la conception des machines électriques en montrant les conséquences des choix de géométries
In PWM converter, emerging technologies, like Sic and GAN, tend to decrease the rise time commutation which increases the occurrence of high frequency phenomenon such as bearing currents and voltage between coils. In this thesis, we aim to develop a predictive model able to give the currents and voltages amplitudes of those parasites. To simplify the understood of the phenomenon, a mock-up was built. It consists of a winding coil in a flexible PCB which represents the wave propagation in a real winding. Therefore, a first model was developed taking into account the effects produced by an increasing frequency. The model gives good results. It will be used in the real traction motor. Measures on a modified motor allowed observing the wave propagation across the coil. Those measures results will be compared to our motor model ones. A model found in the literature has also been studied. For this model, we built a parameters identification method based on several measurement points. This model will also be a compared to our motor model. The last part of this work explains the method used to build the predictive model. A line model is used to give an access to the winding. All parameters have been found with analytical formulations or with numerical simulations to avoid the use of measures. This model gives an access to a voltage between coils and to bearings currents. It can be used during the conception of motor to predict those problems
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