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Interpersonal Dimensions of Goal Pursuit: Goal Support, Shared Goals, Communal Strength, and Generativity in Relationship to Self-Determination TheoryMollica, Christine 14 December 2008 (has links)
Self-Determination Theory (SDT) research on goal pursuit indicates that people with intrinsic goal pursuits experience greater well-being than those with extrinsic goal pursuits. Three nutriments have been suggested by SDT that facilitate intrinsic motivation: autonomy, competence and relatedness. These nutriments, considered social conditions by SDT, have been understudied. However, recent SDT research and the small literature on goal support in relationships suggest that social aspects of goal pursuit are quite relevant and warrant further investigation. This study examined interpersonal dimensions of goal pursuit including Goal Support, Shared Goals, Communal Strength and Generativity. This interpersonal cluster was examined in the context of "active involvement with others" in order to enrich our understanding of the link between goal pursuit and psychological well-being. This study was the first to explore these interpersonal dimensions of goal pursuit and well-being in the context of SDT. Correlations explored the relationships among the interpersonal dimensions and regression analyses were used to explore moderating effects the interpersonal dimensions had on the relationship between self-concordant (intrinsic/extrinsic) goal pursuit and well-being. Shared goal orientation was the only dimension to act as a moderator. Implications include continuing to identify the active role of others in one's goal pursuits and adding further understanding to the relationship between goal pursuit and well-being.
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Risco geotÃcnico: uma abordagem estocÃstica para anÃlise da estabilidade de taludes da Barragem Olho dâÃgua no Estado do Cearà / Geotechnical risk: a stochastic approach to stability analysis of slopes Dam Eye Water in the State of CearÃFranklim Rabelo de Araujo 29 November 2013 (has links)
nÃo hà / A evoluÃÃo das anÃlises de estabilidade de taludes na Engenharia GeotÃcnica
segue de perto o desenvolvimento da MecÃnica dos Solos. Escorregamentos de
taludes sÃo uma das formas mais frequentes de movimento de massa. No caso de
barragens de terra, trÃs dificuldades sÃo encontradas quando se analisa a
estabilidade de taludes: a) a variabilidade dos parÃmetros de resistÃncia do solo; b)
dificuldades de se prever as condiÃÃes de fluxo de Ãgua e as pressÃes
piezomÃtricas resultantes, e c) dificuldade de antecipaÃÃo das formas mais
provÃveis de ruptura, as superfÃcies potenciais a elas associadas e os mecanismos
de ruptura envolvidos. Essas dificuldades refletem diretamente no nÃmero de falhas
em barragens de terra, que responde por 66% dos acidentes em barragens em todo
o mundo. Dados da AgÃncia Nacional de Ãguas apontam que entre 2002 e 2010
foram registrados 800 incidentes com barragens. Como acidentes de grandes
proporÃÃes, cita-se a ruptura da barragem de rejeitos de Cataguazes (MG), em
marÃo de 2003, que deixou milhÃes de pessoas por semanas sem abastecimento,
em razÃo do lanÃamento de soda cÃustica no rio ParaÃba do Sul, bem como o
rompimento da barragem de AlgodÃes, em maio de 2009, no PiauÃ. Dessa forma, em
razÃo das inÃmeras incertezas nos projetos das barragens, Ã necessÃria a utilizaÃÃo
de metodologia que leve em consideraÃÃo a variabilidade dos componentes
envolvidos nas anÃlises de estabilidade de taludes, uma vez que essas incertezas
nÃo sÃo consideradas nos mÃtodos determinÃsticos. A anÃlise probabilÃstica de
estabilidade de taludes, utilizando o mÃtodo de Monte Carlo, torna-se uma
importante ferramenta durante a construÃÃo, enchimento e operaÃÃo de barragens
de terra. PropÃe este trabalho uma metodologia simplificada para estimar os
parÃmetros hidrÃulicos do solo mediante a retroanÃlise das condiÃÃes de fluxo,
comparando as cargas piezomÃtricas medidas no maciÃo, com as calculadas por um
programa de computaÃÃo comercial, para, em seguida, estimar a probabilidade de
falha nos taludes da barragem de terra. A probabilidade de falha do talude de
jusante, anÃlise na condiÃÃo de cheia mÃxima e anÃlise de estabilidade do talude de
montante na condiÃÃo de rebaixamento rÃpido, foram realizadas para o caso da
barragem Olho dâÃgua, no Estado do CearÃ. / The evolution of slope stability analysis in geotechnical engineering has followed
closely the development of soil mechanics . Slope landslides are one of the most
frequent forms of mass movement . In the case of earth dams, three difficulties are
encountered when analyzing the slope stability: a) the variability of soil strength
parameters, b) difficulty of predicting the conditions of water flow and resulting
piezometric pressures, and c) difficulty in predicting the most probable forms of
rupture, the potential surfaces associated to them, and the rupture mechanisms
involved . These difficulties reflect directly on the number of failures recorded with
dams, which accounts for 66 % of accidents in dams around the world. Data from the
National Water Agency of Brazil show that between 2002 and 2010, 800 incidents
were recorded dams. As major accidents, the rupture of tailings in Cataguazes dam
in the state of Minas Gerais in March 2003, which left millions of people without water
for weeks , due to leakage of caustic soda in the ParaÃba do Sul river , as well as the
failure in the AlgodÃo Dam, in May 2009, in Piauà state in northeastern Brazil may be
mentioned . Thus, because of the many uncertainties in the projects of dams, the use
of a methodology that takes into account the variability of the components involved in
the analysis of slope stability of dams is necessary, since these uncertainties are not
considered in deterministic methods. The probabilistic analysis of slope stability using
the Monte Carlo method, turns out to be an important evaluating tool during
construction, filling and operation of earth dams. This work proposes a simplified
methodology for estimating soil hydraulic parameters, by means of back-analysis of
seepage conditions, comparing the pressure heads measured by standpipe
piezometer in the dam, together with those calculated by commercial computing
program to, then, estimate the dam slopes probability of failures. The reliability
analysis of the downstream slope of the dam in the high level of water condition was
done, such as the backslope stability analysis during rapid drawdown of the Olho
dâÃgua dam in the State of CearÃ, Brazil.
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Hill-Fort Sites and Tumuli in the Shkodra Plain Region of Northern Albania: A Geospatial PerspectiveLambert, Dora Jane 09 December 2016 (has links)
The objective of this research was to determine the environmental and social factors that led to the shift of settlement patterning from agro-pastoral in the late Neolithic to hillort sites at the turn of the Early Bronze Age and why burial mounds (tumuli) were erected further than anticipated from corresponding hillort sites in the Shkodra Plain region in Northern Albania. Geospatial techniques were used to examine 168 tumuli and seven hillort sites. These were mapped to examine visibility, viewshed, slope, and potential prehistoric networks. Based on the landscape visibility GIS results, it was found that hillort sites and tumuli were part of an social landscape that thrived on trade. It was determinable that the shift of the social landscape was related to Northern trade routes and probable changes in paleo-lake levels. This new evidence provides insight to Albanian prehistoric culture and has implications to related studies in the Balkans.
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Biodegradabilní kostní implantáty / Biodegradable bone implantsGalanová, Zuzana January 2018 (has links)
This master thesis is focused on producing orthopaedic implant materials and measuring their corrosion properties. It describes the bone and its structure, types, bone ossification and healing. It defines functions of orthopaedic implants and mentions the types of implants – biodegradable and non-biodegradable. The thesis interprets what corrosion is, what categories of corrosion exist and how does the corrosion influence orthopaedic implants. Preparing the solution of stimulated body fluid and manufacturing samples of different metal combinations (of iron, manganese, phosphorus, magnesium, silver and zinc) is included in this thesis, together with corrosion measurements, microscopic observations, EDAX analysis, metallographic analysis, microhardness testing of samples and pH changes measurements of solutions, and the results are interpreted and explained.
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'n Vergelykende studie tussen Pt en Pd vir die elektro-oksidasie van waterige SO₂ asook ander model elektrochemiese reaksies / Adri YoungYoung, Adri January 2014 (has links)
The pressure on clean and sustainable energy supplies is increasing. In this regard energy conversion by electrochemical processes plays a major role, for both fuel cell reactions and electrolysis reactions. The sulphur dioxide oxidation reaction (SOR) is a common reaction found in the Hybrid Sulphur Cycle (HyS) and the HyS is a way to produce large-scale hydrogen (H2). The problem with the use of the HyS and fuel cells is the cost involved as large amounts of Pt are required for effective operation. The aim of the study was to determine whether there was an alternative catalyst which was more efficient and cost-effective than Pt. The oxygen reduction reaction (ORR), the ethanol oxidation reaction (EOR) and SOR were studied by means of different electrochemical techniques (cyclovoltammetry (CV), linear polarization (LP) and rotating disk electrode (RDE)) on polycrystalline platinum (Pt) and palladium (Pd). The SRR and EOR are common reactions occurring at the cathode and anode, respectively, in fuel cells and these reactions have been investigated extensively. The reason for studying the reactions was as a preparation for the SOR.
This study compared polycrystalline Pt and Pd for the different reactions, with the main focus on the SOR as Pd is considerably cheaper than Pt, and for the SOR polycrystalline Pd has by no means been investigated intensively. Polycrystalline Pt and Pd were compared by different electrochemical techniques and analyses. The Koutecky-Levich and Levich analyses were used to (i) calculate the number of e- involved in the relevant reaction, (ii) to determine whether the reaction was mass transfer controlled at high overpotentials and (iii) whether the reaction mechanism changed with potential. Next the kinetic current density ( k) was calculated from Koutecky-Levich analyses, which was further used for Tafel slope analyses. If it was not possible to carry out the analyses, the activation energy (Ea) was used to determine the electrocatalytic activity of the catalyst. The electrocatalytic activity was also determined by comparing onset potentials (Es), peak potentials (Ep) and limited/maximum current density ( b/ p) of each catalyst. This study was only a preliminary study for the SOR and therefore, further studies are certainly required. It seemed Pd shows better electrocatalytic activity than Pt for the SRR in an alkaline electrolyte because of similar Es, but Pd produced a higher cathodic current density. Pt showed a lower Es than Pd for the SRR in an acid electrolyte, but Pd delivered a higher cathodic current density. This, therefore, means that the SRR in an acid electrolyte is kinetically more favourable on Pd than on Pt. For the EOR better electrocatalytic activity was obtained with Pd than with Pt in an alkaline electrolyte due to higher current densities at lower potentials and Pd showed lower Ea values than Pt in the potential range normally used for fuel cells. Pd was inactive for EOR in an acid electrolyte, while a reaction occurred on Pt. A possible reason for this observation may be due to the H2 absorbing strongly on Pd thus blocking the active positions on the electrode surfaces, preventing further reaction. Pd showed higher electrocatalytic activity for the SOR due to lower Es and higher current densities at low potentials.
From the RDE studies it was established that the SRR in an alkaline electrolyte on polycrystalline Pt and Pd was mass transfer controlled at low potentials (high overpotentials), but the SRR in an acid electrolyte was only mass transfer controlled on Pt. The SOR was not mass transfer controlled on polycrystalline Pt and Pd at high potentials (high overpotentials). These assumptions were confirmed by Levich analysis.
Using Koutecky-Levich analysis, it was determined that the reaction mechanism on polycrystalline Pt and Pd changed with potential for SRR in an alkaline electrolyte and the SOR. For the SRR in an acid electrolyte the reaction mechanism remained constant with changes in potential on polycrystalline Pd, but the reaction mechanism on polycrystalline Pt changed with potential. These assumptions were confirmed by the number of e-, calculated using Koutecky-Levich analyses. Levich and Koutecky-Levich analyses were not performed for EOR as an increase in rotation speed did not produce an increase in current density.
Tafel slope analyses were conducted by making use of overpotentials and k, where possible. As in the case of ethanol, it was not possible to execute Koutecky-Levich analyses and, therefore, it was not possible to perform Tafel slope analyses using k. Tafel slope analyses for the EOR was therefore performed with normal current densities at 0 rotations per minute (rpm). The reaction mechanisms on Pt and Pd for the SRR in alkaline and acidic electrolytes differed due to different Tafel slopes. Pt and Pd displayed similar Tafel slopes for the EOR in alkaline electrolyte, thus suggesting that the reaction mechanisms on Pt and Pd were the same. For the SOR it seemed that the reaction mechanism on Pt and Pd were similar because of similar Tafel slopes. This was only a preliminary and comparative study for polycrystalline Pt and Pd, and the reaction mechanism was not further studied by means of spectroscopic techniques. / MSc (Chemistry), North-West University, Potchefstroom Campus, 2014
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'n Vergelykende studie tussen Pt en Pd vir die elektro-oksidasie van waterige SO₂ asook ander model elektrochemiese reaksies / Adri YoungYoung, Adri January 2014 (has links)
The pressure on clean and sustainable energy supplies is increasing. In this regard energy conversion by electrochemical processes plays a major role, for both fuel cell reactions and electrolysis reactions. The sulphur dioxide oxidation reaction (SOR) is a common reaction found in the Hybrid Sulphur Cycle (HyS) and the HyS is a way to produce large-scale hydrogen (H2). The problem with the use of the HyS and fuel cells is the cost involved as large amounts of Pt are required for effective operation. The aim of the study was to determine whether there was an alternative catalyst which was more efficient and cost-effective than Pt. The oxygen reduction reaction (ORR), the ethanol oxidation reaction (EOR) and SOR were studied by means of different electrochemical techniques (cyclovoltammetry (CV), linear polarization (LP) and rotating disk electrode (RDE)) on polycrystalline platinum (Pt) and palladium (Pd). The SRR and EOR are common reactions occurring at the cathode and anode, respectively, in fuel cells and these reactions have been investigated extensively. The reason for studying the reactions was as a preparation for the SOR.
This study compared polycrystalline Pt and Pd for the different reactions, with the main focus on the SOR as Pd is considerably cheaper than Pt, and for the SOR polycrystalline Pd has by no means been investigated intensively. Polycrystalline Pt and Pd were compared by different electrochemical techniques and analyses. The Koutecky-Levich and Levich analyses were used to (i) calculate the number of e- involved in the relevant reaction, (ii) to determine whether the reaction was mass transfer controlled at high overpotentials and (iii) whether the reaction mechanism changed with potential. Next the kinetic current density ( k) was calculated from Koutecky-Levich analyses, which was further used for Tafel slope analyses. If it was not possible to carry out the analyses, the activation energy (Ea) was used to determine the electrocatalytic activity of the catalyst. The electrocatalytic activity was also determined by comparing onset potentials (Es), peak potentials (Ep) and limited/maximum current density ( b/ p) of each catalyst. This study was only a preliminary study for the SOR and therefore, further studies are certainly required. It seemed Pd shows better electrocatalytic activity than Pt for the SRR in an alkaline electrolyte because of similar Es, but Pd produced a higher cathodic current density. Pt showed a lower Es than Pd for the SRR in an acid electrolyte, but Pd delivered a higher cathodic current density. This, therefore, means that the SRR in an acid electrolyte is kinetically more favourable on Pd than on Pt. For the EOR better electrocatalytic activity was obtained with Pd than with Pt in an alkaline electrolyte due to higher current densities at lower potentials and Pd showed lower Ea values than Pt in the potential range normally used for fuel cells. Pd was inactive for EOR in an acid electrolyte, while a reaction occurred on Pt. A possible reason for this observation may be due to the H2 absorbing strongly on Pd thus blocking the active positions on the electrode surfaces, preventing further reaction. Pd showed higher electrocatalytic activity for the SOR due to lower Es and higher current densities at low potentials.
From the RDE studies it was established that the SRR in an alkaline electrolyte on polycrystalline Pt and Pd was mass transfer controlled at low potentials (high overpotentials), but the SRR in an acid electrolyte was only mass transfer controlled on Pt. The SOR was not mass transfer controlled on polycrystalline Pt and Pd at high potentials (high overpotentials). These assumptions were confirmed by Levich analysis.
Using Koutecky-Levich analysis, it was determined that the reaction mechanism on polycrystalline Pt and Pd changed with potential for SRR in an alkaline electrolyte and the SOR. For the SRR in an acid electrolyte the reaction mechanism remained constant with changes in potential on polycrystalline Pd, but the reaction mechanism on polycrystalline Pt changed with potential. These assumptions were confirmed by the number of e-, calculated using Koutecky-Levich analyses. Levich and Koutecky-Levich analyses were not performed for EOR as an increase in rotation speed did not produce an increase in current density.
Tafel slope analyses were conducted by making use of overpotentials and k, where possible. As in the case of ethanol, it was not possible to execute Koutecky-Levich analyses and, therefore, it was not possible to perform Tafel slope analyses using k. Tafel slope analyses for the EOR was therefore performed with normal current densities at 0 rotations per minute (rpm). The reaction mechanisms on Pt and Pd for the SRR in alkaline and acidic electrolytes differed due to different Tafel slopes. Pt and Pd displayed similar Tafel slopes for the EOR in alkaline electrolyte, thus suggesting that the reaction mechanisms on Pt and Pd were the same. For the SOR it seemed that the reaction mechanism on Pt and Pd were similar because of similar Tafel slopes. This was only a preliminary and comparative study for polycrystalline Pt and Pd, and the reaction mechanism was not further studied by means of spectroscopic techniques. / MSc (Chemistry), North-West University, Potchefstroom Campus, 2014
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