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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

The role of transcendent nature and awe experiences on positive environmental engagement

Davis, Nora 27 October 2016 (has links)
<p> Despite a rich popular narrative that awe-inspiring nature experiences promote environmental behavior, empirical work on this subject is lacking. Recent research has determined that individuals often experience the emotion awe in nature, and that this emotion can lead to reliable shifts in cognition, interpersonal perception, and social behavior. In addition, although research has found that nature exposure can shift environmental behavior, the emotional pathways underlying this association, such as awe, are not yet clear. The current investigation explores through two studies the relationship between transcendent nature and awe experiences with environmental behavior. In study 1 (N = 405), a pre-post online survey assessed (1) the effect of describing a past nature-based transcendent experience in a value-based model of environmental behavior; and (2) what qualities of this experience, such as awe, were most prominent descriptively and as predictors in the model. Regression analyses revealed that describing a nature-based transcendent experience significantly improved the model, and increased participant&rsquo;s openness to change values pre-post. Moreover, a sense of awe was the most prominent experience quality and was positively related to environmental behavior.</p><p> Study 2 employed an experimental design to more concretely explore the role of the transcendent emotion awe in nature on environmental behavior and engagement. A 2x3 factorial design (N = 277) explored whether two factors - (1) reading a climate change message or no message, and (2) viewing videos of awe-inspiring nature, an awe-inspiring built environment, or calming nature - influenced participant&rsquo;s emotional state and environmental behavior intentions, including an in-situ measure of whether they signed a climate change petition presented outside of the building after leaving the lab session. Participants reported feeling less relaxed and interested after reading a climate message in the built (awe) condition compared to the nature conditions. Also, participants in the awe-nature condition reported feeling more relaxed when they were given the climate message to read. Although no significant interactions for environmental behavior intention emerged, for the in-situ measure, participants who viewed nature rather than awe videos were over three times more likely to sign the climate petition.</p><p> Overall, the results of study 1 suggest the theoretical value and interventional benefits of integrating transcendent nature experiences and the emotion awe into value-based models of environmental behavior. The results of study 2 begin to suggest that pro-environmental behavior may depend more on the setting participants are exposed to (nature versus built) rather than on the emotions induced by those settings, such as awe. Implications on education and nature protection policy and practices are discussed.</p>
52

Estimating reliability with discrete growth models

Chandler, James D. 03 1900 (has links)
Approved for public release; distribution is unlimited / Determining the reliability of newly designed systems is one of the most important functions of the acquisition process in the military. Tracking the growth in reliability of a system as it is developed and modified repeatedly is an important part of the acquisition process. This thesis extends and expands a reliability growth simulation program written previously. It analyzes the capabilities and limitations of two discrete reliability growth models to determine which models are most applicable in estimating system reliability under a variety of different growth patterns. Negative growth patterns are also considered. The result ot this thesis is a FORTRAN simulation which enables a more accurate estimate of system reliability using test data generated during the development phase of an acquisition program. Keywords: Theses; Charts; Mathematical models. (Author) / http://archive.org/details/estimatingreliab00chan / Captain, United States Army
53

Multilevel flow modelling as a generalized modelling technique

Bracher, Stephen 18 August 2016 (has links)
A project report submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering by course work and a project Johannesburg, 1993 / With the increasing size and complexity of industrial plants there is a growing need for modelling techniques and tools that can be used to aid the operator in the daily running of the plant. This research investigates a modelling technique, known as multilevel flow modelling (MFM) and assesses its suitability for fault diagnostic applications. A rule base for measurement validation, alarm analysis and fault diagnosis is developed which is independent of the process structure and the number of sensors used, so as not to Lose the generality of the modelling technique. A case study Shows that it is feasible to use MFM for fault diagnosis and that this technique has the flexibility to accommodate alterations.
54

After the degree: research psychology in the 'real world'

Rascher, Candice Lee January 2016 (has links)
A research project submitted in partial fulfillment of the requirements for the degree of BA Masters (Research Psychology) in the Faculty of Humanities, University of the Witwatersrand, February/May 2016. / Research psychology is one of the five categories in which one can register as a psychologist with the Health Professions Council of South Africa (HPCSA). It is, however, the most under-represented and under-researched category of the five. Many people who are eligible to register choose not to, but presumably still obtain employment. This raises questions regarding what these people are doing and what influenced their decisions to register or not to register. The aims of this research study were thus to track former research psychology masters students and gain an understanding of the different career paths this degree led them to, and why they chose to pursue a particular path. In addition, this research aimed to determine whether or not former research psychology masters students registered with the HPCSA as a research psychologist, and their reasons for doing so or not doing so, thus enabling evaluation of the relevance of the category among those with potential eligibility to occupy it. This study also sought to evaluate the degree of transformation in this division of psychology, and provide valuable career information for students interested in studying this degree. A sample of 122 former research psychology masters students was obtained through a purposive snowballing sampling technique. The respondents completed an online survey consisting of a mixture of forced choice and open ended questions. Results showed that it does not seem to be of paramount importance to be registered as a research psychologist with the HPCSA to conduct research that is considered valuable to the community, or, more broadly, to do the kind of jobs that this degree would qualify one to do. Respondents were able to pursue a variety of different career paths despite their registration status. These career paths included working in academia, health/social research, marketing and corporate research, monitoring and evaluation and psychometrics. Results also showed that there is some evidence for the transformation of psychology, with a slightly more diverse group of students in recent years, however not enough to show significance
55

The Role of Basic Psychological Needs in Determining Well-Being: A Study of Diverse Samples of Emerging Adults

Unknown Date (has links)
Suggestions from the self-determination theory and extant literature suggest the fulfillment of basic psychological needs (i.e., autonomy, competence, and relatedness) is necessary for well-being and to prevent ill-being. Autonomy is the perception that an individual is the source of their own behavior and can act in ways congruent with his or her sense of self. Competence is the sense of confidence one has in his or her abilities to be effective in their interactions within the environment. Relatedness is the sense of connection to important others, that one cares for and is cared for by others. Emerging adulthood is a unique developmental stage marked by instability, in which many common psychological disorders (i.e., ill-being) reach their peak. This dissertation explored the interconnections between basic psychological needs and well- and ill-being during emerging adulthood, using two distinct samples. The first study used a latent profile approach to identify subgroups of emerging adults based on their levels of basic psychological need satisfaction and frustration; the subgroups, known as profiles, were then compared with regard to their reports of well-being (i.e., life satisfaction and vocational identity) and ill-being (i.e., anxiety and depression). Using latent profile analysis, a two-profile solution was found using an exploratory sample of college students (N = 177). The first profile had significantly lower levels of basic psychological need satisfaction and higher levels of basic psychological need frustration than the second profile, both seem to generally reflect the theoretical notion that needs exist on a continuum from satisfied to frustrated. The two-profile structure was verified using a confirmatory sample of college students (N = 375). Significant group differences were then found using a multivariate analysis of variance (MANOVA), in that members of the profile with lower levels of basic psychological need satisfaction and higher basic psychological need frustration had significantly lower levels of life satisfaction and vocational identity and higher levels of anxiety and depression. Implications for theorists, clinicians, and college administrators and educators are discussed. The second study examined the role of an autonomy-thwartive environment, specifically hostile deployment experiences, and its' influence on soldiers' competence, conceptualized as performance, and mental health, as well as how these relationships differ based on relational environments. A sample of combat-exposed soldiers between the ages of 18 and 25 from the restricted military personnel Army Study to Assess Risk and Resilience among Servicemembers (STARRS) dataset (N = 5,284) was used. Findings suggested that higher levels of hostile deployment experiences were found to be related to a greater likelihood of anxiety, depression, and posttraumatic stress disorder (PTSD). Higher levels of hostile deployment experiences were also linked to poorer military performance. Poorer military performance was, in turn, related to a greater likelihood of anxiety, depression, and PTSD. Using moderated mediation structural equation modeling, buffering effects of the detrimental impact of hostile deployment experiences were found for both unit cohesion and interpersonal relational experiences. Implications for those working with military service personnel, specifically marriage and family therapists, are focused on ways to bolster unit cohesion and healthy interpersonal relationships as a protective factor for young service members. / A Dissertation submitted to the Department of Family and Child Sciences in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Spring Semester 2017. / March 20, 2017. / Basic Psychological Needs, Emerging Adults, Mental Health, Military, Relationships, Well-being / Includes bibliographical references. / Mallory Lucier-Greer, Professor Directing Dissertation; John Reynolds, University Representative; Ming Cui, Committee Member; Lenore McWey, Committee Member.
56

GENERALIZED FRACTIONAL PROGRAMMING

Unknown Date (has links)
Consider the nonlinear programming problem that involves the product of two functionals and that takes the form: / Maximize / P(x) = {(phi)(,1)(x)}('(alpha)(,1)) (.) {(phi)(,2)(x)}('(alpha)(,2)) / subject to / g(x) (LESSTHEQ) 0 / where x (epsilon) R('n), (alpha)(,1), (alpha)(,2) (epsilon) R, (phi)(,i)((.)), i = 1, 2, and each component of g((.)) (epsilon) R('m), are scalar functions, continuously differentiable. / Kuhn-Tucker type necessary conditions for optimality are established, following the Dubovitskii-Milyutin formalism and a duality theory is developed, which represents an extension of that for the Nonlinear Fractional Programming problem (for which (alpha)(,1) = 1 and (alpha)(,2) =-1) as well as the ordinary Nonlinear Programming problem (with (alpha)(,1) = 1 and (phi)(,2)(x) (TBOND) 1). / As an extension from the finite dimensional case, a new class of Continuous Nonlinear Programming problems is introduced, including, in particular, the class of Continuous Fractional Programming problems, which encounters applications on the study of aerodynamic shapes, particularly that of flap top wings in hypersonic flow. As a representative of this class, we consider the problem / Maximize / (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) / subject to / (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) / where (alpha)(,1), (alpha)(,2) (epsilon) R, z(t) is an n-dimensional vector function with each component p-integrable on {0, T}, T finite 1 < p < (INFIN); f(z(t), t) and g(z(t), t) are m- and -dimensional vector functions, respectively; c(t) and H(t, s) are, respectively, m x 1 and m x time dependent matrices whose entries are p-integrable on {0, T} and {0, T} x {0, T}, respectively; (phi)(,i)((.), t), i = 1, 2, and each component of f and g are scalar functions, continuously differentiable in its first argument throughout {0, T}. / Following the same approach as the finite case, Kuhn-Tucker type necessary conditions and a duality theory are developed, extending those of the ordinary Continuous Programming problem, for which (alpha)(,1) = 1 and (alpha)(,2) = 0. / Source: Dissertation Abstracts International, Volume: 42-06, Section: B, page: 2492. / Thesis (Ph.D.)--The Florida State University, 1981.
57

THE STABILITY OF CONTINUOUS PROGRAMMING

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 41-01, Section: B, page: 0323. / Thesis (Ph.D.)--The Florida State University, 1980.
58

SOLUTIONS TO CONTINUOUS TIME PROGRAMMING PROBLEMS

Unknown Date (has links)
Consider the linear continuous time programming problem / (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) / subject to / (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) / and / z(t) (GREATERTHEQ) 0, t (ELEM) {0, T}. / The vector function z(t) maps {0, T} into R('n), a(t) is an n-dimensional row-vector and c(t) is an m-dimensional column vector. The matrices B(t) and K(t, s) are of dimension mxn. / We show that under certain conditions the optimal solution contains at most m positive elements, for almost all t (ELEM) {0, T}. This makes it possible to express the solution as an infinite matrix series. One property of the solutions is that the vector function z(t) is not necessarily smooth for all t at optimum. Rather, different components may be positive over different intervals. The points at which the change occurs are called join points. We show that all join points are natural, that is they occur when a variable goes to zero either in the original problem or in an associated dual problem. / Our approach leads to a confirmation of a conjecture about the smoothness of solutions between join points. We also prove a conjecture which had been made about the behavior of the solutions as t (--->) (INFIN). / The previous developments lead to an algorithm for the problem. The algorithm makes use of the simplex method to obtain solutions using a matrix series. The method is incorporated in a computer program and examples are given. / We discuss the nonlinear problem and prove a theorem on the convergence of a penalty function approach on a precompact metric space. / Source: Dissertation Abstracts International, Volume: 42-10, Section: B, page: 4168. / Thesis (Ph.D.)--The Florida State University, 1981.
59

CONTRIBUTIONS TO THE THEORY OF CONTINUOUS TIME PROGRAMMING

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 36-06, Section: B, page: 2989. / Thesis (Ph.D.)--The Florida State University, 1975.
60

CONTRIBUTIONS TO DUALITY THEORY IN CONTINUOUS NONLINEAR PROGRAMMING

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 38-09, Section: B, page: 4420. / Thesis (Ph.D.)--The Florida State University, 1977.

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