Spelling suggestions: "subject:"mixedmethod"" "subject:"mixedmethods""
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Mixed framework for Darcy-Stokes mixturesTaicher, Abraham Levy 09 February 2015 (has links)
We consider the system of equations arising from mantle dynamics introduced by McKenzie (J. Petrology, 1985). In this multi-phase model, the fluid melt velocity obeys Darcy's law while the deformable "solid" matrix is governed by a highly viscous Stokes equation. The system is then coupled through mass conservation and compaction relations. Together these equations form a coupled Darcy-Stokes system on a continuous single-domain mixture of fluid and matrix. The porosity φ, representing the relative volume of fluid melt to the bulk volume, is assumed to be much smaller than one. When coupled with solute transport and thermal evolution in a time-dependent problem, the model transitions dynamically from a non-porous single phase solid to a two-phase porous medium. Such mixture models have an advantage for numerical approximation since the free boundary between the one and two-phase regions need not be determined explicitly. The equations of mantle dynamics apply to a wide range of applications in deep earth physics such as mid-ocean ridges, subduction zones, and hot-spot volcanism, as well as to glacier dynamics and other two-phase flows in porous media. Mid-ocean ridges form when viscous corner flow of the solid mantle focuses fluid toward a central ridge. Melt is believed to migrate upward until it reaches the lithospheric "tent" where it then moves toward the ridge in a high porosity band. Simulation of this physical phenomenon required confidence in numerical methods to handle highly heterogeneous porosity as well as the single-phase to two-phase transition. In this work we present a standard mixed finite element method for the equations of mantle dynamics and investigate its limitations for vanishing porosity. While stable and optimally convergent for porosity bounded away from zero, the stability estimates we obtain suggest, and numerical results show, the method becomes unstable as porosity approaches zero. Moreover, the fluid pressure is no longer a physical variable when the fluid phase disappears and thus is not a good variable for numerical methods. Inspired by the stability estimates of the standard method, we develop a novel stable mixed method with uniqueness and existence of solutions by studying a linear degenerate elliptic sub-problem akin to the Darcy part of the full model: [mathematical equation], where a and b satisfy a(0)=b(0)=0 and are otherwise positive, and the porosity φ ≥ 0 may be zero on a set of positive measure. Using scaled variables and mild assumptions on the regularity of φ, we develop a practical mass-conservative method based on lowest order Raviart-Thomas finite elements. Finally, we adapt the numerical method for the sub-problem to the full system of equations. We show optimal convergence for sufficiently smooth solutions for a compacting column and mid-ocean ridge-like corner flow examples, and investigate accuracy and stability for less regular problems / text
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Transnational Higher Education Networks for Learning and Teaching (TNLTs) in GeographyWakefield, Kelly January 2013 (has links)
Transnational Higher Education Networks for Learning and Teaching (TNLTs) in Geography are networks of academic geographers that facilitate a common interest in exchanging knowledge about higher education learning and teaching. Participation within these learning and teaching networks arguably provides benefits of information sharing but is often compromised by barriers such as finance and time. The aim of this study is to contribute to geographies of higher education by exploring academic networking practices for learning and teaching through geographers motivations, experiences and outcomes of participation alongside the role that technology plays in facilitating these. The subject of learning and teaching is an increasingly important area of study. The complex relationship between the practices of learning and teaching alongside research and administration duties within higher education has been previously explored yet little discussion is offered on academics who focus on learning and teaching practice. However, within the context of human geography research TNLTs as defined within this thesis have only received cursory treatment. This study situates TNLTs under the umbrella of geographies of higher education that are increasingly being studied with focuses on transnational academic mobility, international student mobility and international collaborations in higher education. This study sketches a conceptual framework for engaging in academic networking by bringing research together on TNLTs, Continuing Professional Development (CPD), higher education on a global scale, Communities of Practice (CoP) and the technology driven-network society that comprise five bodies of literature that have not been considered collectively before. Due to a lack of literature and previous work on TNLTs, this thesis applies grounded theorising that generated findings out of the data rather than testing a hypothesis. Such inductive methodology develops and constructs theory and is a useful approach to researching TNLTs because it also allows for a combination of different research methods. In this thesis, various ways to access TNLTs are blended to effectively study them, including both face-to-face and online surveys and interviews.
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Jobbcoachers personliga nätverk : en undersökning av kommunala jobbcoachers nätverk och hur kontakterna används för att få personer i sysselsättningKlockerud, Åsa, Krogh, Jessica January 2014 (has links)
Det finns mycket forskning som tyder på att nätverk är betydelsefullt på arbetsmarknaden. Forskningen har hittills fokuserat på de arbetssökande och vilken betydelse deras sociala nätverk har för att få ett jobb. I vår studie fokuserar vi däremot på de som sitter på ”andra sidan”. Uppsatsens fokus är de arbetsrelaterade nätverken hos fem kommunala jobbcoacher. Syftet med studien är att undersöka kommunala förmedlares sociala nätverk och på vilket sätt de använder nätverket i sitt uppdrag att coacha personer till någon form av sysselsättning. För att undersöka nätverken har vi utgått från tre frågeställningar: 1. Hur ser förmedlares arbetsrelaterade nätverk ut? 2. Vilka typer av länkar i nätverket anser förmedlare vara mest användbara i arbetsrelaterade frågor? 3. Hur sker kommunikationen mellan förmedlare och deras nätverkskontakter? För att försöka få svar på dessa frågor genomförde vi fem semi-strukturerade intervjuer. Vårt tillvägagångssätt för att studera dessa nätverk har utgått från en mixad metod där kvalitativ ansats blandas med kvantitativ ansats. För att kunna analysera datamaterialet och kunna säga något om strukturen och innehållet i nätverken har vi använt oss av teoretiska mått som ofta används i nätverksstudier. Resultatet visar bland annat att nätverken bland dessa fem förmedlare skiljer sig både på vilka kontakter som ingår i nätverken och på vilken sorts av kontakter de anser vara mest värdefulla i sin yrkesutövning. Många av de kontakter som förmedlarna anser vara viktiga för att få vetskap om lediga sysselsättningar är arbetskollegor som de träffar ofta och diskuterar arbetsrelaterade frågor med. Gemensamt var att de alla anser att de får vetskap om lediga sysselsättningar genom sina nätverk, vilket tyder på att de har effektiva nätverk. Däremot anser samtliga att de troligen kan använda sina nätverk i större utsträckning än de gör nu.
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A mixed method study of second cancer risk among cancer survivorsWilkins, Krista 22 September 2010 (has links)
Recent research shows that cancer survivors are at greater risk of developing cancer than the general population. Knowledge of the magnitude of second cancer risk and cancer-specific deaths among cancer survivors, factors that influence their second cancer risk, cancer survivors’ perceptions of second cancer risk and current practices and existing gaps in follow-up care is urgently needed if we hope to prepare survivors and their healthcare providers as to how best to monitor their long-term health. An exploratory mixed method study, guided by Kaplan and colleagues (2000) multilevel approach to the health determinants, was conducted to provide a detailed understanding of second cancer risks among cancer survivors. Data collection methods included: (1) qualitative survey of current practices in the follow-up care offered for cancer survivors across Canada, (2) population-based health databases (cancer registry and health insurance databases), and (3) qualitative interviews on cancer survivors’ perceptions of second cancer risks.
Coordinated follow-up services are not universally available across Canada. Yet, cancer survivors have a 4-7-fold increased risk of developing cancer compared to the general population in Nova Scotia and Manitoba. Second cancer risks varied by demographic and disease-related factors such as age at first cancer diagnosis, cancer type, treatment era, and time since diagnosis. Second cancer risk does not exist only as an epidemiological calculation. Second cancer risk, from the perspective of cancer survivors, is shaped by more intuitive conceptual models than statistical models of risk. The theme, Life After Cancer – Living with Risk, described survivors’ sense that second cancer risk is now a part of their everyday lives.
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A mixed method study of second cancer risk among cancer survivorsWilkins, Krista 22 September 2010 (has links)
Recent research shows that cancer survivors are at greater risk of developing cancer than the general population. Knowledge of the magnitude of second cancer risk and cancer-specific deaths among cancer survivors, factors that influence their second cancer risk, cancer survivors’ perceptions of second cancer risk and current practices and existing gaps in follow-up care is urgently needed if we hope to prepare survivors and their healthcare providers as to how best to monitor their long-term health. An exploratory mixed method study, guided by Kaplan and colleagues (2000) multilevel approach to the health determinants, was conducted to provide a detailed understanding of second cancer risks among cancer survivors. Data collection methods included: (1) qualitative survey of current practices in the follow-up care offered for cancer survivors across Canada, (2) population-based health databases (cancer registry and health insurance databases), and (3) qualitative interviews on cancer survivors’ perceptions of second cancer risks.
Coordinated follow-up services are not universally available across Canada. Yet, cancer survivors have a 4-7-fold increased risk of developing cancer compared to the general population in Nova Scotia and Manitoba. Second cancer risks varied by demographic and disease-related factors such as age at first cancer diagnosis, cancer type, treatment era, and time since diagnosis. Second cancer risk does not exist only as an epidemiological calculation. Second cancer risk, from the perspective of cancer survivors, is shaped by more intuitive conceptual models than statistical models of risk. The theme, Life After Cancer – Living with Risk, described survivors’ sense that second cancer risk is now a part of their everyday lives.
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Beliefs and Technology - Does One Lead to the Other? Evaluating the Effects of Teacher Self-Efficacy and School Collective Efficacy on Technology Use in the ClassroomStudnicki, Elaine 24 April 2012 (has links)
This exploratory mixed method study builds upon previous research to investigate the influence of teacher self- and collective efficacy on technology use in the classroom. This population was purposefully sampled to examine first- and second order technology barriers, instructional strategies, and human influences on technology. The quantitative finding was supported by qualitative analysis of the teacher interviews and led to the conclusion that even thought there were strong teacher tendencies towards a belief in using technology actual practice demonstrated a lack of productivity or transference of that belief into classroom practice. A high self- and collective efficacy had no effect on technology use in the classroom and a belief in technology did not lead to the use of technology.
<br>The study explored three research questions: 1) what is the effect of teacher self-efficacy on technology use in the classroom, 2) what is the effect of collective efficacy on technology use in the classroom, and 3) what is the relationship among teacher self-efficacy, collective efficacy, and barriers that inhibit technology use in a K-12 classroom setting? Thirty-five teachers in a New Jersey K-8 school district volunteered to take a 36-question survey. Three teachers were interviewed to corroborate the survey data.
<br> This study is unique in the combined analysis of self- and collective efficacy and technology. It raises several questions for future study. Teacher responses overwhelmingly identified first order or extrinsic barriers as impediments to technology. These included poor technical support, access, time issues, and a lack of vision and training. These barriers are decades old and have been acknowledged for as long as technology has been in the classroom. Why, despite thirty years of technology in education, do the same barriers that existed in the very beginning continue to be strong deterrents of technology use?
<br>Teachers identified administrators as the least influential on teacher practices. If this is so, how can there be such a high sense of collective efficacy? How much influence does the collective agency have on classroom teacher behavior? Specifically, at what point in a teacher's decision-making does the collective agency over-ride personal beliefs and what are the characteristics that contribute to this conflict and possible submissive behavior?
<br> Finally, are we seeking answers to the wrong questions? Is it possible that teachers and educational systems are not able to modify intrinsic and standard operating practices to utilize technology successfully? / School of Education / Instructional Technology (EdDIT) / EdD / Dissertation
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The contribution of social support to employee psychological well-being : an exploratory mixed-methods case studyKowalski, Tina Helen Parkin January 2013 (has links)
Stress and mental health issues are now the most common cause of workplace absence. Increasing evidence points to the need for organisations to take steps to enhance well-being at work for employees. Social support has been identified as one key factor affecting employee psychological well-being, however, the definition and conceptualisation of the term continues to be debated. To date, research examining the relationship between social support and well-being at work tends to be predominantly quantitative and to prioritise work-based sources of support above other sources of support. Few workplace interventions aimed at improving employee well-being appear to have a specific focus on enhancing social support. This thesis presents findings from a mixed-methods case study of a large, public sector organisation in Scotland. The study had four phases: an online survey (n=158), semi-structured interviews (n=31), a diary phase (n=11) and a final interview (n=11). Higher levels of social support were associated with a higher level of psychological well-being. Findings highlighted the importance of various work and non-work based sources of social support, such as peer support and support from friends, and various dimensions of support too, such as ‘distant vs. proximal’ support. Potential negative effects of social support were also identified, for example, when perceived as interfering. Women reported higher levels of support and of positive mental well-being than did men. Interview and diary data revealed a range of contextual, organisational and individual factors that affected both access to and availability of social support, and the relationship between social support and employee well-being. Recent organisational changes appeared to be particularly influential. Employee opinion regarding existing organisational well-being initiatives varied on the basis of whether the support was formal or informal and in terms of perceived versus received support. Social support was valued highly by respondents with regard to improving employee well-being. Open and honest communication, physical presence of support and familiarity with context-specific knowledge were of particular pertinence. This thesis contributes to knowledge in three ways. Substantively, the importance of examining social support more holistically is highlighted in order to better understand the relationship between social support and employee well-being. Methodologically, this mixed methods approach proved fruitful in generating a richness and depth of data largely untapped by previous, predominantly quantitative, studies. Finally, the findings have practical implications for HR personnel and policy makers as they offer an insight into the contribution of various sources and dimensions of social support to employee well-being, as understood by employees.
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The immigrant sibling: an exploration of acculturation and enculturation profilesQuan, Cindy 11 September 2018 (has links)
Acculturation and enculturation processes and sibling relationship quality are important constructs for understanding the psychosocial wellbeing of immigrant adolescents. In this thesis, I used a mixed-method approach to (a) understand how similar or different siblings’ cultural orientations are, (b) the role siblings may play in shaping one another’s cultural orientation, and (c) how changes in cultural orientation are related to sibling relationship quality. Quantitative data were collected from 31 adolescent sibling dyads at two time points, and qualitative data were collected from individual interviews with 16 young adults. Participants in both samples identified as having a Chinese cultural background and immigrated to Canada with their family before the age of 14. The results of the qualitative interviews suggested that siblings often perceived themselves as culturally similar, although the quantitative data were not congruent with that view. There was ample evidence that siblings influence one another’s cultural profiles. For example, in the quantitative data, higher cultural involvement by one sibling, especially in the Canadian dimension, predicted decreases in the other sibling’s involvement in that same domain 18 months later. These patterns were corroborated with themes derived through the interviews. The thematic analyses identified five factors that fostered similarities and differences in the cultural profiles of immigrant siblings, as well as four themes describing the perceived effects of being similar or different. The qualitative findings suggested that there are few cultural conflicts among siblings. Instead, siblings act as cultural mediators in parent-child conflicts, and they are in a unique position to understand and support each other. This study provided preliminary insight into how similar or different Chinese immigrant siblings are in a Canadian metropolitan context. Overall, the findings illustrate ways in which siblings play an important role in the family by supporting one another in adjusting to life in Canada. / Graduate
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A Study on Retention and Achievement: Assessment of International Students' Resilience and Coping StrategiesChin, Fui-Yee Phoebe 01 December 2016 (has links)
The purpose of this mixed-method study was to examine and to explore international students’ perceptions of resilience and how they coped with stress during their pursuit of a college degree. This study also explored forms of assistance international students received while studying at the university, how students capitalized on their own qualities to overcome obstacles, and to discover resilience factors that empowered international students despite challenges they encountered during the course of study. The researcher utilized two surveys, namely the Resilience Scale (RS) (Wagnild & Young, 1993) and the Coping Strategy Indicator (CSI) (Amirkhan, 1990), and a focus group interview to collect data for the study. The sample of the study consisted of 117 students for the RS, 106 students for the CSI, and 6 students for the focus group. All students were internationals from a Midwestern university in the United States. The findings of the study revealed that there was no significant difference in the RS scores for both undergraduate and graduate international students or for females and males respectively. The study also confirmed that there was no significant difference in the CSI scores for undergraduate and graduate international students. However, there was a significant difference between females and males in their CSI scores, suggesting that females were more likely than males to seek social support when they encountered challenges in life. Qualitative data from the focus group yielded meaningful insights on the obstacles that international students had to overcome, assistance international students received while in the United States, and protective factors students possessed in order to be successful in the university. The study also included a factor analysis of the data that confirmed a 3-factor structure of CSI (labeled respectively as Problem Solving, Seeking Social Support, and Avoidance). Even though factor analysis also verified the original 25-item 5-factor structure of RS, yielding a 5-factor structure of resilience (Meaningfulness, Equanimity, Self-Reliance, Perseverance, and Existential Aloneness), due to several cross loadings of the variables onto the factors, the analysis failed to verify the same variables contributed to the original 5-factor in RS. Plausible explanations for the discrepancy of the study of RS were explored.
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Influence de la passion du jeu chez les joueurs de poker : étude de recherche mixte / Influence of the gambling passion among poker players: a mixed method studyMorvannou, Adèle January 2017 (has links)
La santé publique s’inquiète des risques de problèmes de jeu chez les joueurs de poker (JdP). Alors que la littérature souligne l’importance de la passion chez les joueurs de hasard et d’argent, son influence chez les JdP est totalement méconnue. Jusqu’alors, l’emprunt d’un devis transversal est la règle pour l’ensemble des études s’étant intéressées à la passion chez des joueurs. Selon la littérature, deux formes de passion coexistent chez les joueurs, la passion obsessive (PO) et la passion harmonieuse (PH), leur intensité respective étant plus ou moins importante.
Cette étude mixte séquentielle comprend une première phase quantitative corrélationnelle transversale (n=159) et longitudinale (n=116), suivie d’une seconde phase qualitative descriptive (n=12) permettant d’approfondir et de contextualiser les données quantitatives. Cette étude, qui s’inscrit dans une étude plus large, comprend des joueurs qui se considèrent JdP, recrutés à travers le Québec et vise à : 1) évaluer l’association entre les deux formes de passion et les problèmes de jeu; 2) évaluer l’influence, un an plus tard, des deux formes de passion sur les problèmes de jeu; 3) étudier la pertinence du concept de passion et mieux comprendre les liens entre la passion et les problèmes de jeu selon les joueurs. La phase quantitative a fait l’objet d’analyses de régression logistique multivariées et la phase qualitative, une analyse de contenu thématique.
Les résultats transversaux et longitudinaux de la première phase quantitative sont concordants. Dans ces deux volets, la PO est positivement associée aux problèmes de jeu à un temps donné (p<.05) et la PO double le risque d’avoir des problèmes de jeu un an plus tard (p<.01) alors que la PH n’est pas associée. La phase qualitative appuie globalement les résultats quantitatifs. Les joueurs rencontrés se sont montrés enthousiastes à aborder la passion du poker et considèrent que le terme passion est pertinent pour aborder leur relation avec cette activité. Alors que la grande majorité a indiqué avoir été ou être encore passionnée de poker, ils associent la PO aux problèmes de jeu, même s’il est possible d’être passionné sans avoir de problèmes de jeu. Par ailleurs, la passion serait l’un des facteurs influençant les comportements de jeu, mais n’est pas nécessairement déterminante puisqu’un joueur peut continuer à jouer sans être passionné et à l’inverse être passionné sans nécessairement jouer fréquemment. Compte tenu de la pertinence pour les JdP de ce concept et de son influence sur les comportements de jeu, il est important de prévenir la passion obsessive. / Abstract : Public health is concerned about the risks of gambling problems among poker players.
While literature emphasizes the importance of passion among gamblers, its influence
among poker players is totally unknown. Until then, using a cross-sectional design is the
rule for all the studies interested in passion among gamblers. According to the literature,
two forms of passion coexist in players, obsessive passion (OP) and harmonious passion
(HP), with a variable intensity, respectively.
This sequential mixed method study includes a first cross-sectional (n = 159) and
longitudinal (n = 116) quantitative phase, followed by a second descriptive qualitative
phase (n = 12) allowing to deepen and contextualize the quantitative data. This study,
which is part of a broader study, includes players who consider themselves poker players,
recruited throughout Quebec and aims to: 1) assess the association between the two forms
of passion and gambling problems; 2) assess the influence, one year later, of the two forms
of passion on gambling problems; 3) study the relevance of the concept of passion and to
better understand the associations between passion and gambling problems according to the
poker players. Multivariate logistic regression and a thematic content analysis were used to
the quantitative and qualitative phases, respectively.
Cross-sectional and longitudinal results of the first quantitative phase are consistent. In
both cases, OP is positively associated with gambling problems at a given time (p <.05)
and PO doubles the risk of gambling problems a year later (p <.01) whereas PH is not
associated. The qualitative phase generally supports the quantitative results. Poker players
interviewed were enthusiastic to speak about the passion of poker and consider that the
term ‘passion’ is relevant to describe their relationship with this activity. While the vast
majority said they have been or still are passionate about poker, they associate the PO with
gambling problems, although it is possible to be passionate without having gambling
problems. Moreover, passion is one of the factors influencing gambling behaviours but is
not necessarily determinant since a poker player can continue to play without being
passionate and conversely being passionate without necessarily playing frequently. Given
the relevance of this concept for poker players and its influence on gambling behaviours, it
is important to prevent obsessive passion.
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