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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.
71

Help in Overweight/Obesity Prevention Effort (HOPE) Study – A Study to Identify Resiliency Factors to Childhood Obesity and Comparison Between Body Mass Index and Figure Rating Scales

Hanson, Rebecka L. 01 May 2011 (has links)
Obesity results from a complex interaction between diet, physical activity, and the environment. The purposes of this study were to identify behaviors associated with resilience to childhood obesity, and to compare the sensitivity of the Figure Rating Scales (FRS) in reflecting Body Mass Index (BMI). Fifty health professionals in nutrition and 35 low-income, parent-and-child pairs completed the study. Children aged 6-11, perceived as “normal-weight” by their parents, were recruited. Five children had a measured BMI above the 85th percentile. Using a picture-sort method, each participant responded to a series of questions about 13 childhood obesity-related messages. Results included comparison between health professionals, parents, and children about 1) familiarity toward each message, 2) frequency in following the recommendation, 3) perception of ease for others to follow, and 4) perception of effectiveness to help prevent childhood obesity. Health professionals and parents had similar familiarity regarding all 13 messages. However, in terms of practicality, health professionals and parents differed significantly in eight messages that they reported “always taught/followed,” seven messages that they “sometimes taught/followed,” and two messages that they “seldom or never taught/followed.” In most messages, children’s observation about what the family followed differed from what parents reported following. In terms of ease for others to follow “Watch portion sizes” and “Tell children to eat all of the meal before getting dessert,” health professionals and parental perception differed significantly. In terms of effectiveness in childhood obesity prevention, health professionals and parents agreed on 12 of 13 messages. Health professionals did not find message “Tell children to eat all of the meal before getting dessert” to be effective in preventing childhood obesity, whereas parents did. FRS and measured BMI were significantly correlated among health professionals (r=0.75), parents (r=0.72), and children (r=0.53 for children ages 8-11, r=0.64 when a mother selected a silhouette for her child). For different subgroups, parent-and-child silhouette selection was closely correlated (r= 0.84). However, correlation between child’s BMI percentile and silhouette was nonsignificant in most subgroups (r= 0.47). In conclusion, FRS was effective among adults and older children (aged ≥8) in reflecting BMI but not among younger children (aged 6-7).
72

An Industrial Training Approach to a National Manpower Development Effort: A Proposal

Cuayo, Leonisa M. 01 May 1976 (has links)
The objective of this thesis is to propose an approach or a process by which a national industrial training system can be instituted for the Philippines; and specifying the role which the National Manpower and Youth Council should play in the undertaking. The thesis outlines some of the general features of the manpower development systems in several selected countries, followed by an outline of the Philippine manpower development system, and the environment in which the Industrial training system in the Philippines would operate. The existing organization of the National Manpower and Youth Council is described and a plan of action for the creation of a new system outlined. The plan of action includes a detailed outline of the steps necessary for the successful creation of a pilot industry training board and a discussion of the subsequent requirements and strategy needed to develop the entire national training system.
73

Estimation of fish biomass indices from catch-effort data : a likelihood approach

Roa-Ureta, Ruben, n/a January 2009 (has links)
Two dimensional stocks of fish can be assessed with methods that mimic the analysis of research survey data but that use commercial catch-effort data. This finite population approach has scarcely been used in fisheries science though it brings about very large sample sizes of local fish density with models of only moderate levels of complexity. The extracted information about the status of the stock can be interpreted as biomass indices. Statistical inference on finite populations has been the locus of a highly specialized branch of sampling-distribution inference, unique because observable variables are not considered as random variables. If statistical inference is defined as "the identification of distinct sets of plausible and implausible values for unobserved quantities using observations and probability theory" then it is shown that Godambe's paradox implies that the classical finite populations approach is inherently contradictory as a technique of statistical inference. The demonstration is facilitated by the introduction of an extended canonical form of an experiment of chance, that apart from the three components identified by Birnbaum, also contains the time at which the experiment is performed. Realization of the time random variable leaves the likelihood function as sole data-based mathematical tool for statistical inference, in contradiction with sampling-distribution inference and in agreement with direct-likelihood and Bayesian inference. A simple mathematical model is introduced for biomass indices in the spatial field defined by the fishing grounds. It contains three unknown parameters, the natural mortality rate, the probability of observing the stock in the area covered by the fishing grounds, and mean fish density in the sub-areas where the stock was present. A new theory for the estimation of mortality rates is introduced, using length frequency data, that is based on the population ecology analogue of Hamilton-Jacobi theory of classical mechanics. The family of equations require estimations of population growth, individual growth, and recruitment pattern. Well known or new techniques are used for estimating parameters of these processes. Among the new techniques, a likelihood-based geostatistical model to estimate fish density is proposed and is now in use in fisheries science (Roa-Ureta and Niklitschek, 2007, ICES Journal of Marine Science 64:1723-1734), as well as a new method to estimate individual growth parameters (Roa-Ureta, In Press, Journal of Agricultural, Biological, and Environmental Statistics). All inference is done only using likelihood functions and approximations to likelihood functions, as required by the Strong Likelihood principle and the direct-likelihood school of statistical inference. The statistical model for biomass indices is a hierarchical model with several sources of data, hyperparameters, and nuisance parameters. Even though the level of complexity is not low, a full Bayesian formulation is not necessary. Physical factors, mathematical manipulation, profile likelihoods and estimated likelihoods are used for the elimination of nuisance parameters. Marginal normal and multivariate normal likelihood functions, as well as the functional invariance property, are used for the hierarchical structure of estimation. In this manner most sources of information and uncertainty in the data are carried over up the hierarchy to the estimation of the biomass indices.
74

Aspects of the Effort-reward imbalance model of psychosocial stress in the working life

Fahlén, Göran January 2008 (has links)
<p>Fahlén, G. (2008). Aspects on the Effort-reward Imbalance model of psychosocial stress in the work environments. Sundsvall, Sweden: Mid Sweden University, Department of Health Sciences. ISBN 978-91-85317-94-3.</p><p>Since the late 1970s, work related stress has increasingly been recognized as an important determinant for ill-health and disease. One of the most influential stress models is the Effort-Reward Imbalance model (ERI), which stipulates that an imbalance between the perceived effort spent at work and rewards received results in noxious stress. Those with a coping behaviour called Work-related Overcommitment (WOC), including an inability to withdraw from work obligations are especially vulnerable. The model has shown strong explanatory value for a large numbers of harmful health outcomes.</p><p>The general aim of this thesis was to contribute to the development of the ERI model by exploring the properties of this model in relation to its theoretical assumptions, construct, and application and to improve the knowledge of validity of the ERI-model.</p><p>The study sample that was used in three papers emanated from the WOLF study (Work, Lipids and Fibrinogen). The analyses were confined to the subset of individuals who answered the ERI questions (n=1174) with complete answers. In one paper, data from the SKA study (Sick leave, Culture and Attitudes) were used and they comprised all employees at the Swedish Social Insurance Agency responsible for management and compensation of illness in the working population (n=5700). All data are based on questionnaires.</p><p>The results indicate that ERI and WOC are risk factors for sleep disturbances and fatigue. A palpable threshold effect was seen between quartile three and four. Since these symptoms are strongly stress related, our results support the utility of the ERI and WOC scales in assessing stress in working life.</p><p>Agreement between single questions in the original and an approximate instrument for measuring ERI were low, whereas the agreement between the two ERI scales was reasonable. When approximate instruments are used, questions and scales must be presented thoroughly to facilitate comparisons and the results should be interpreted with caution. Today there are no reasons to use such instruments in the ERI model.</p><p>One statement in the ERI model is that individuals with the coping behaviour characterised as WOC are particularly vulnerable to an imbalance between perceived effort and reward; i.e., that ERI and WOC interact. No such effect was shown in relation to disturbed sleep and fatigue. There is no convincing evidence that ERI and WOC interact in synergy. Analysis demonstrated that WOC was relatively stable in perceived unchanged conditions as measured by the original, more comprehensive instrument as well as by the present, shortened instrument. Positively or negatively perceived changes in ERI correspond to changes in WOC. This result suggests that WOC, at least in part, may act as not only a coping strategy but also as an outcome from ERI. Taken together, these results concerning WOC, suggest that studies to clarify the role of the WOC dimension are needed.</p><p>The ERI model states that, when individuals stay in unfavourable conditions characterised as ERI, because there are few alternatives on the labour market or when the individual is at risk of being laid off or of facing downward mobility, they are in a “locked in position” (LIP). A strong association between LIP and ERI was shown, supporting this statement.</p> / <p>Fahlén, G. (2008). Aspects on the Effort-reward Imbalance model of psychosocial stress in the work environments. Sundsvall, Sweden: Mid Sweden University, Department of Health Sciences. ISBN 978-91-85317-94-3.</p><p>Arbetsrelaterad stress har sedan slutat av sjuttiotalet alltmer blivit uppmärksammat som en viktig bestämningsfaktor för ohälsa. En av de mest inflytelserika stressmodellerna är Ansträngning-belönings modellen (Effort-reward imbalance, ERI) som stipulerar att en obalans mellan ansträngning och belöning i arbetet orsakar en skadlig stress och att de som har ett särskilt coping-beteende som kännetecknas bland annat av oförmåga att dra sig tillbaka från sitt arbete (Work related overcommitment WOC) är särskilt sårbara. Modellen har visat ett starkt förklaringsvärde för många negativa hälsoutfall.</p><p>Det övergripande syftet med avhandlingen var att bidra till utvecklingen av ERI-modellen genom att utforska modellens egenskaper i relation till de teoretiska antagandena, uppbyggnad och tillämpning samt att öka kunskapen om modellens validitet.</p><p>Den epidemiologiska studie som användes i tre artiklar var WOLF-studien (WOrk, Lipids and Fibrinogen) där analyserna genomfördes på den delmängd som hade svarat på ERI-frågorna (n=1174) och som hade kompletta svar. För en artikel användes material från SKA-studien (Sjukskrivning, Kultur och Attityder) och omfattade de som arbetade med ohälsoärenden vid Försäkringskassan (n=5700) i samtliga fall användes data från frågeformulär.</p><p>Resultaten visade att ERI och WOC utgör riskfaktorer för störd sömn och dagtrötthet. En tydlig tröskeleffekt kunde skönjas mellan tredje och fjärde kvartilen. Eftersom dessa symptom är starkt stressrelaterade, gav resultaten stöd för användbarheten av ERI och WOC instrumenten för att skatta stress i arbetslivet.</p><p>Överensstämmelsen mellan enskilda frågor i orginalinstrumentet för ERI och ett approximativt var låg, medan överensstämmelsen mellan de två ERI skalorna bedömdes som rimlig. När approximativa instrument används bör frågor och skalor presenteras utförligt för att jämförelser ska underlättas och resultaten bör tolkas med försiktighet.</p><p>En utgångspunkt i ERI-modellen är att individer som har ett coping-beteende som karakteriseras som WOC är särskilt sårbara för en obalans mellan ansträngning och belöning, d.v.s. att ERI och WOC interagerar i synergi. Ingen sådan effekt kunde styrkas i relation till störd sömn och dagtrötthet. Det saknas också övertygande bevis för att en sådan effekt finns. WOC-måttet är relativt stabilt i oförändrade arbetsförhållanden i såväl orginalinstrumentet som i det nuvarande förkortade. Upplevda positiva eller negativa förändringar i ERI påverkade WOC i samma riktning. Resultaten indikerade att WOC, åtminstone delvis kan utgöra ett utfall av ERI, inte endast en copingstrategi. Dessa resultat gör att studier för att tydliggöra WOC-dimensionens roll i ERI modellen är önskvärda.</p><p>En annan utgångspunkt i modellen är att en av de situationer man stannar i ogynnsamma arbetsförhållanden kännetecknade av ERI, är att man har små möjligheter att byta arbete beroende på att man har få möjligheter på arbetsmarknaden eller är utsatt för risk att bli uppsagd eller att få sämre arbete, man är ”inlåst”. Resultaten visade på en stark association mellan inlåsning och ERI och gav därmed stöd åt antagandet.</p>
75

Utmattningsdepression : En studie om det moderna arbetslivets relation till psykisk ohälsa utifrån fem kvalitativa intervjuer

Dahlin, Erica, Forslund, Emma January 2010 (has links)
<p><strong>The purpose of this essay is to try to understand the relationship between the structures of modern working life and the development of burnout. By using the method of qualitative interviews we wanted to see if the Effort-Reward Imbalance Model could be applied to the data we had collected. Two questions have been highlighted in our research: </strong><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p></p><ol><p> </p><li>• Is it possible to establish a relationship between the structures of modern working life and the development of burnout among the subjects interviewed? </li><p> </p><li>• Is it possible to explain the development of burnout among our interviewed subjects through the Effort-Reward Imbalance Model?  </li><p> </p><p> </p></ol><p>Our theoretical frames are the general theories of the modern society and the modern working life as developed by Anthony Giddens, Ulrich Beck and Zygmunt Bauman. We have also used Johannes Siegrist’s medical-sociological Effort-Reward Imbalance Model (ERI-Model). Our main findings are that the characteristics of modern working life mostly have had a negative affect on the lives of four of the five interviewed subjects. Hence, modern working life is one contributing factor to the development of burnout among our interviewed subjects. Four of five interview subjects fulfilled the three hypotheses postulated by the Effort-Reward Imbalance Model. This indicates that these individuals are at an increased risk of developing poor health. It also indicates that an imbalance between efforts and rewards as well as an imbalance between internal and external factors at the workplace might have contributed to their development of burnout.</p><p> </p><p> </p><p> </p><p> </p>
76

Noise Reduction Schemes for Digital Hearing Aids and their Use for the

Marzinzik, Mark, Mark.Marzinzik@ePost.de 19 December 2000 (has links)
No description available.
77

Aspects of the Effort-reward imbalance model of psychosocial stress in the working life

Fahlén, Göran January 2008 (has links)
Fahlén, G. (2008). Aspects on the Effort-reward Imbalance model of psychosocial stress in the work environments. Sundsvall, Sweden: Mid Sweden University, Department of Health Sciences. ISBN 978-91-85317-94-3. Since the late 1970s, work related stress has increasingly been recognized as an important determinant for ill-health and disease. One of the most influential stress models is the Effort-Reward Imbalance model (ERI), which stipulates that an imbalance between the perceived effort spent at work and rewards received results in noxious stress. Those with a coping behaviour called Work-related Overcommitment (WOC), including an inability to withdraw from work obligations are especially vulnerable. The model has shown strong explanatory value for a large numbers of harmful health outcomes. The general aim of this thesis was to contribute to the development of the ERI model by exploring the properties of this model in relation to its theoretical assumptions, construct, and application and to improve the knowledge of validity of the ERI-model. The study sample that was used in three papers emanated from the WOLF study (Work, Lipids and Fibrinogen). The analyses were confined to the subset of individuals who answered the ERI questions (n=1174) with complete answers. In one paper, data from the SKA study (Sick leave, Culture and Attitudes) were used and they comprised all employees at the Swedish Social Insurance Agency responsible for management and compensation of illness in the working population (n=5700). All data are based on questionnaires. The results indicate that ERI and WOC are risk factors for sleep disturbances and fatigue. A palpable threshold effect was seen between quartile three and four. Since these symptoms are strongly stress related, our results support the utility of the ERI and WOC scales in assessing stress in working life. Agreement between single questions in the original and an approximate instrument for measuring ERI were low, whereas the agreement between the two ERI scales was reasonable. When approximate instruments are used, questions and scales must be presented thoroughly to facilitate comparisons and the results should be interpreted with caution. Today there are no reasons to use such instruments in the ERI model. One statement in the ERI model is that individuals with the coping behaviour characterised as WOC are particularly vulnerable to an imbalance between perceived effort and reward; i.e., that ERI and WOC interact. No such effect was shown in relation to disturbed sleep and fatigue. There is no convincing evidence that ERI and WOC interact in synergy. Analysis demonstrated that WOC was relatively stable in perceived unchanged conditions as measured by the original, more comprehensive instrument as well as by the present, shortened instrument. Positively or negatively perceived changes in ERI correspond to changes in WOC. This result suggests that WOC, at least in part, may act as not only a coping strategy but also as an outcome from ERI. Taken together, these results concerning WOC, suggest that studies to clarify the role of the WOC dimension are needed. The ERI model states that, when individuals stay in unfavourable conditions characterised as ERI, because there are few alternatives on the labour market or when the individual is at risk of being laid off or of facing downward mobility, they are in a “locked in position” (LIP). A strong association between LIP and ERI was shown, supporting this statement. / Fahlén, G. (2008). Aspects on the Effort-reward Imbalance model of psychosocial stress in the work environments. Sundsvall, Sweden: Mid Sweden University, Department of Health Sciences. ISBN 978-91-85317-94-3. Arbetsrelaterad stress har sedan slutat av sjuttiotalet alltmer blivit uppmärksammat som en viktig bestämningsfaktor för ohälsa. En av de mest inflytelserika stressmodellerna är Ansträngning-belönings modellen (Effort-reward imbalance, ERI) som stipulerar att en obalans mellan ansträngning och belöning i arbetet orsakar en skadlig stress och att de som har ett särskilt coping-beteende som kännetecknas bland annat av oförmåga att dra sig tillbaka från sitt arbete (Work related overcommitment WOC) är särskilt sårbara. Modellen har visat ett starkt förklaringsvärde för många negativa hälsoutfall. Det övergripande syftet med avhandlingen var att bidra till utvecklingen av ERI-modellen genom att utforska modellens egenskaper i relation till de teoretiska antagandena, uppbyggnad och tillämpning samt att öka kunskapen om modellens validitet. Den epidemiologiska studie som användes i tre artiklar var WOLF-studien (WOrk, Lipids and Fibrinogen) där analyserna genomfördes på den delmängd som hade svarat på ERI-frågorna (n=1174) och som hade kompletta svar. För en artikel användes material från SKA-studien (Sjukskrivning, Kultur och Attityder) och omfattade de som arbetade med ohälsoärenden vid Försäkringskassan (n=5700) i samtliga fall användes data från frågeformulär. Resultaten visade att ERI och WOC utgör riskfaktorer för störd sömn och dagtrötthet. En tydlig tröskeleffekt kunde skönjas mellan tredje och fjärde kvartilen. Eftersom dessa symptom är starkt stressrelaterade, gav resultaten stöd för användbarheten av ERI och WOC instrumenten för att skatta stress i arbetslivet. Överensstämmelsen mellan enskilda frågor i orginalinstrumentet för ERI och ett approximativt var låg, medan överensstämmelsen mellan de två ERI skalorna bedömdes som rimlig. När approximativa instrument används bör frågor och skalor presenteras utförligt för att jämförelser ska underlättas och resultaten bör tolkas med försiktighet. En utgångspunkt i ERI-modellen är att individer som har ett coping-beteende som karakteriseras som WOC är särskilt sårbara för en obalans mellan ansträngning och belöning, d.v.s. att ERI och WOC interagerar i synergi. Ingen sådan effekt kunde styrkas i relation till störd sömn och dagtrötthet. Det saknas också övertygande bevis för att en sådan effekt finns. WOC-måttet är relativt stabilt i oförändrade arbetsförhållanden i såväl orginalinstrumentet som i det nuvarande förkortade. Upplevda positiva eller negativa förändringar i ERI påverkade WOC i samma riktning. Resultaten indikerade att WOC, åtminstone delvis kan utgöra ett utfall av ERI, inte endast en copingstrategi. Dessa resultat gör att studier för att tydliggöra WOC-dimensionens roll i ERI modellen är önskvärda. En annan utgångspunkt i modellen är att en av de situationer man stannar i ogynnsamma arbetsförhållanden kännetecknade av ERI, är att man har små möjligheter att byta arbete beroende på att man har få möjligheter på arbetsmarknaden eller är utsatt för risk att bli uppsagd eller att få sämre arbete, man är ”inlåst”. Resultaten visade på en stark association mellan inlåsning och ERI och gav därmed stöd åt antagandet.
78

Integrating dependencies into the technology portfolio: a feed-forward case study for near-earth asteroids

Taylor, Christianna Elizabeth 15 November 2011 (has links)
Technology Portfolios are essential to the evolution of large complex systems. In an effort to harness the power of new technologies, technology portfolios are used to predict the value of integrating them into the project. This optimization of the technology portfolio creates large complex design spaces; however, many processes operate on the assumption that their technology elements have no dependency on each other, because dependencies are not well defined. This independence assumption simplifies the process, but suggests that these environments are missing out on decision power and fidelity. Therefore, this thesis proposed a way to explain the variations in Portfolio recommendations as a function of adding dependencies. Dependencies were defined in accordance with their development effort figures of merit and possible relationships. The thesis then went on to design a method to integrate two dependency classes into the technology portfolio framework to showcase the effect of incorporating dependencies. Results indicated that Constraint Dependencies reduced the portfolio or stayed the same, while Value Dependencies changed the portfolio optimization completely; making the user compare two different optimization results. Both indicated that they provided higher fidelity with the inclusion of the information added. Furthermore, the upcoming NASA Near-Earth Asteroid Campaign was studied as a case study. This campaign is the plan to send humans to an asteroid by 2025 announced by President Obama in April 2010. The campaign involves multiple missions, capabilities, and technologies that must be demonstrated to enable deep-space human exploration. Therefore, this thesis capitalized on that intention to show how adopting technology in earlier missions can act as a feed-forward method to demonstrate technology for future missions. The thesis showed the baseline technology portfolio, integrated dependencies into the process, compared its findings to the baseline case, and ultimately showed how adding higher fidelity into the process changes the user's decisions. Findings concerning the Near-Earth Asteroid Campaign, the use of dependencies to add fidelity and implications for future work are discussed.
79

The Effects of Viewing Angle on the Acquisition, Retention and Recognition of a Complex Dance Sequence

Smith, Jenna 30 January 2013 (has links)
The benefits of observing a model when acquiring a new motor skill are well known, however, there is little research on the influence of viewing angle of the model. The purpose of the present experiment was to assess whether a looking-glass (face on) or subjective (facing away) viewing angle would result in different acquisition and retention levels when learning a complex Zumba dance sequence. Greater cognitive effort was expected during the looking-glass condition, consequently resulting in slower acquisition but greater physical performance scores and error recognition/identification. Thirty females were evenly divided into the looking-glass or subjective group and began with the pre-test phase to assess degrees of motivation, self-efficacy, and physical performance. Participants were then lead through six acquisition dances, within which they performed the to-be-learned sequence 18 times. An assessment of cognitive effort followed, then post-test performances and error recognition/identification scores were obtained to conclude the study. While both the looking-glass and subjective conditions demonstrated equal rates of acquisition (p>.05), the looking-glass group performed significantly fewer errors during the post-test (p<.05) and were significantly better at identifying errors when a video of the dance sequence was shown from the same viewing angle as the acquisition phase (p<.05). No differences were reported between the two conditions with respect to cognitive effort (p>.05). Based on the results of this study, the looking-glass viewing angle appears to result in better learning of a dance sequence, but cannot be explained by cognitive effort.
80

Mental Workload Measurement Using the Intersaccadic Interval

Pierce, Eldon Todd 22 September 2009 (has links)
Mental workload is commonly defined as the proportion of a person's total mental capacity in use at a given moment. A measure of mental workload would have utility in a number of rehabilitation medicine applications, but no method has been adequately examined for these purposes. A candidate measure is the intersaccadic interval (ISI), which is the duration between two successive saccades. Previous studies indicate that ISI length may be linked to mental workload, but this link is poorly understood for tasks that are not primarily visual. Therefore, the current study was an investigation of ISI and workload intensity in three non-visual tasks: mental arithmetic, verbal fluency, and audio perception. Workload was manipulated through changes in task difficulty as well as study participant motivation level. An analysis of eye movements and other experimental workload measures indicated a significant association between audio perceptual workload and ISI length.

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