Dissertations / Theses on the topic 'The Model of Accommodation'
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Urs, Raksha. "Investigation of Accommodation and Presbyopia using Ultrasound Imaging during Ex Vivo Simulated Accommodation." Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_dissertations/360.
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The goal of this project is to obtain quantitative images of the lens and the ciliary body to validate EVAS-II (Second generation Ex Vivo Accommodation Simulator). To accomplish this goal it was necessary to develop methods, instrumentation and image processing techniques to acquire 3D images in EVAS-II, using UBM (Ultrasound Bio Microscope), and to apply these techniques to non-human primate eyes. The lens studies included measurement of speed of sound in the lens to reconstruct accurate images of the lens, development of instrumentation to measure the un-distorted lens shape and development of a mathematical model to quantify the whole lens shape. Speed measurements showed that the speed of sound exhibits a gradient profile in the equatorial plane, similar to refractive index and protein distributions in the lens. Lens shape measurements showed that the UBM can be used to accurately measure thickness, diameter, cross-sectional area, volume and surface area of the lens. The ciliary body studies included development of instrumentation and algorithms to obtain 3-D images of tissue in EVAS-II and development of methodology to quantify ciliary body movement during stretching. Studies showed that the accommodation process in young baboon eyes in EVAS-II is comparable to the in vivo process in rhesus monkeys. The UBM can be used to obtain reliable quantitative information about the lens and the ciliary body. 3-D UBM enables monitoring of ciliary body motion of the entire accommodative apparatus.
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Rich, Barbara Sharon. "Development of an in vitro model for accommodation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq28982.pdf.
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Aristidou, Chrystalleni. "Issues in the accommodation of model uncertainty in macro-econometric modelling." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/36130/.
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This thesis deals with different types of uncertainty in various macroeconomic contexts and investigates ways in which these can be accommodated by adopting flexible techniques that allow a robust inference in estimation, testing and prediction. This thesis covers a wide range of aspects in macroeconomic analysis, including the choice of an appropriate unit root test, inference when the presence of breaks and the autocorrelation properties of data are unknown, characterisation of inflation dynamics when structural and specification uncertainty are present, as well as model uncertainty in forecasting when real-time data are available. Chapter 1 presents the general motivations and describes the main research objectives and methodology for each chapter, providing a thesis outline at the same time. Chapter 2 examines the behaviour of OLS-demeaned/ detrended and GLS-demeaned/ detrended unit root tests that employ stationary covariates in situations where the magnitude of the initial condition of the time series under consideration may be nonnegligible. We show that the asymptotic power of such tests is very sensitive to the initial condition; OLS- and GLS- based tests achieve relatively high power for large and small magnitudes of the initial condition, respectively. Combining information from both types of test via a simple union of rejections strategy is shown to effectively capture the higher power available across all initial condition magnitudes. In Chapter 3, we consider a two-step procedure for estimating level break size(s) when the presence of the structural break(s) is uncertain and when the order of integration of the data is unknown. In other words, we deal with uncertainty over the appropriate filtering of the data, as well as structural uncertainty over the existence of a break. Our approach is motivated by the well known interplay between the unit roots and structural changes: Evidence in favour of unit roots can be a manifestation of structural changes and vice versa. The proposed procedure is shown to exhibit substantial accuracy gains in estimating the level break-size and breakpoint. Chapter 4 provides a characterisation of U.S. inflation dynamics within a generalised Phillips Curve framework that accommodates uncertainties about the duration a given Phillips Curve holds and the specification of the relationship, in addition to parameter and stochastic uncertainties accommodated within a typical Phillips Curve analysis. Our approach is based on an innovative method to deal with such uncertainties based on Bayesian model averaging techniques. Employing data for the U.S. in the period 1950q1- 2012q4, the estimated version of the "meta" Phillips Curve provides an interesting characterisation of inflation dynamics which is in accordance with a number of distinguished studies. Chapter 5 investigates the extent to which nowcast and forecast performance is enhanced by the use of real-time datasets that incorporate past data vintages and survey data on expectations in addition to the most recent data. The paper proposes a modelling framework and evaluation procedure which allow a real-time assessment and a final assessment of the use of revisions and survey data judged according to a variety of statistical and economic criteria. Both survey data and revisions data are found to be important in calculating density forecasts in forecasting the occurrence of business cycle events. Through a novel "fair bet" exercise, it is shown that models that incorporate survey and/or revisions data achieve higher profits in decision-making. The analysis also highlights the need to focus on future growth and inflation dynamics relevant to decision-makers rather than relying on simple point forecasts.
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Choh, Vivian Cheng-Pei. "A physiological model to measure optical and biophysical changes during avian accommodation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ65228.pdf.
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Carlin, Paul. "Modelling vergence, accommodation and their interaction." Thesis, Glasgow Caledonian University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241881.
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The vergence and accommodation systems, which are examples of physiological control systems, enable us to acquire and maintain clear single images of objects at a variety of distances in our visual world. Vergence and accommodation systems are interact with one each other and have both visual and non-visual components thus adding to their complexity. This thesis reviews the evolution of control theory models of vergence and accommodation from the 1960's to the present day and has outlined several properties of the systems which require further study. The thesis introduces the concept of Fuzzy Logic Control (FLC) to models of oculomotor control. FLC offers a new approach to modelling natural control systems and produces more realistic models than those obtained using conventional control theory techniques. Several characteristics of the vergence and accommodation systems were investigated with the aim of incorporating experimental data into control theory models using conventional techniques and FLC. The accommodation response to anisometropic stimuli was measured objectively. No evidence of a non-consensual response was found, from which it can be concluded that accommodation is consensual. A control theory model of binocular accommodation was simulated to illustrate the control strategies adopted by the accommodation during anisometropic stimulation. A Virtual Reality (VR) stimulus was used to investigate the possibility of adaptation of the crosslink components of vergence and accommodation by placing different demands on the vergence and accommodation systems. Crosslink behaviour was altered as a result of the VR stimulus which suggests that the links between vergence and accommodation (accommodative vergence and vergence accommodation) are amenable to adaptation. Control theory models were used to illustrate the effects of the VR stimulus on vergence and accommodation. The effect of proximity was investigated by measuring accommodation responses in the presence and absence of proximal cues. The effect of proximal cues under closed loop conditions was found to be minimal which suggests that proximal cues are only effective when visual cues are reduced. The results were extended to include the vergence system and a FLC model of proximal vergence and accommodation was implemented. Simulation of the model produced similar findings to a previous study which supports the use of FLC in models of oculomotor control. Voluntary vergence and accommodation were measured objectively under open loop conditions in a group of naive subjects. All subjects were able to produce voluntary responses corresponding to near and far. The ability of subjects to distinguish intermediate distances was more varied. The results show that voluntary responses can be produced without training and it is suggested that voluntary vergence and accommodation may be an important mode of response. The results were included in a control model of voluntary vergence and accommodation using FLC. The work presented provides support for the use of Fuzzy Logic in models of oculomotor control which can be used to improve models and complement existing models using conventional techniques.
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Kim, Sara. "International Students' Cross-cultural Communication Accommodation through Language Approximation and Topic Selection Strategies on Facebook and Its Relationship to the Students' Acculturation Attitude, Psychological Adjustment, and Socio-cultural Adaptation." Thesis, The University of Arizona, 2015. http://hdl.handle.net/10150/596088.
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Language use and communicative behaviors are important indicators of sojourners' adjustment. The current research was conducted to understand international students' communication behavior on Facebook during their adjustment period in the US and its relationship to the students' acculturative attitude (identification with heritage and mainstream culture), current psychological adjustment level, socio-cultural adaptation level, and target audience on Facebook. Two main theories provided the theoretical framework of the study: Giles' communication accommodation theory (1973) and Berry's acculturation model (1984). Snowball and convenience samples were used to recruit 178 international students from different universities across the US. A mixed approach of online survey and content analysis was used to test the hypotheses and research questions. The results showed that during the stay in the US, international students accommodate their language and topic choice towards their American peers on Facebook. Particularly, it was found that language accommodation levels increase as the students' length of stay in the US increases. The results also demonstrate that international students use Facebook mainly to communicate with friends who reside in the US. When students had higher levels of mainstream identification, they were likely to target American friends as their audience on Facebook and thus have more language and topic accommodation. Additionally, acculturation attitude (heritage and mainstream identification) predicted the students' language accommodation level. Lastly, the study showed that there is a positive relationship between language accommodation and sociocultural adjustment. The findings of the study not only expand the scope of communication accommodation theory and acculturation model, but also enhance understanding of international students' online communication patterns, their purposes, and practical consequences upon their adjustment in the US. This is important because it can be useful in finding ways to improve the students' experience in the US.
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Hadj, nacer Mustafa. "Tangential momentum accommodation coefficient in microchannels with different surface materials (measurements and simulations)." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4764/document.
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Cette thèse est consacrée à l'étude des écoulements de gaz raréfiés à travers divers micro-conduits de type circulaire et rectangulaire dans des conditions isotherme et stationnaire. L'objectif de la thèse est de contribuer à l'étude de l'interaction gaz-surface notamment en déterminant le coefficient d'accommodation de la quantité de mouvement pour différent matériaux de surface (Or, Silice, Acier inoxydable et Sulfinert) associés à différents types de gaz (hélium, azote, argon et dioxyde-de-carbone). Afin d'atteindre cet objectif, on adopte un triple point de vue : expérimental, théorique et numérique. L'aspect expérimental est réalisé par des mesures de débit massique à travers les micro-conduits, en utilisant la méthode dite « à volume constant ». L'aspect théorique original est développé à travers une nouvelle approche basée sur la résolution de l'équation de Stokes. Cette approche a permis d'écrire une expression analytique de débit massique en régime de glissement, qui prenne en compte les effets bidimensionnels dans une section de conduit rectangulaire. Cette approche complètement explicite, est conduite au deuxième ordre. Enfin l'aspect numérique permet de calculer le débit massique, en régimes transitionnel et moléculaire libre, en résolvant numériquement l'équation cinétique BGK linéarisée. La comparaison des mesures de débit massique avec l'équation analytique, en régime de glissement, ou avec les calculs numériques, en régimes transitionnel et moléculaire libre, nous a permis de déduire des coefficients de glissement et les coefficients d'accommodation correspondant à chaque couple gaz-surface dans tous les régimes de raréfactionThis thesis is devoted to the study of rarefied gas flows through micro-channels of various cross sections (circular and rectangular) under isothermal and stationary conditions. The objective of this thesis is to contribute to the study of gas-surface interaction by determining the tangential momentum accommodation coefficient for different surface materials (gold, silica, stainless steel and Sulfinert) and associated to various gases (helium, nitrogen, argon and carbon-dioxide). To achieve this goal three aspects are considered: experimental, theoretical and numerical. The experimental aspect is considered by measuring the mass flow rate through microchannels using the constant volume technique. The theoretical aspect is considered by the development of a new approach based on the Stokes equations. This approach yields to the analytical expression of the mass flow rate in the slip regime, which takes into account the second order effects. The last aspect, numerical, is considered by the numerical simulations of the mass flow rate in the transitional and free molecular flow regimes by solving the linearized BGK kinetic model. The comparison between the measured mass flow rates and the analytically expressions in the slip regime or with the results of numerical simulations in the transitional and free molecular regimes enabled to deduce the tangential momentum accommodation coefficients corresponding to each pair gas-surface in all flow regimes
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Soloninka, John William. "Accommodation in an urban agricultural education program in Ohio: a case study." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1070283391.
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Borja, David. "Dynamic Optical Model of the Primate Crystalline Lens and Implications for the Restoration of Accommodation." Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_dissertations/355.
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The human crystalline lens is a complex, inhomogeneous and dynamic optical element which enables the eye to adjust focus in a process known as accommodation. Age related changes in the optical and mechanical properties of the lens cause a loss in accommodative ability leading to a condition known as presbyopia. Several experimental surgical techniques are under development for the correction of presbyopia. The goal of this dissertation is to better understand the relationship between the crystalline lens shape, its non-uniform refractive index gradient and its optical power and their changes with age and accommodation. In this study direct lens power and shape measurements were acquired on isolated lenses, and on lenses mounted in a lens stretching system designed to simulate accommodation. Several lens shape and power measurement techniques were developed for this study including a Scheimpflug camera system optimized for imaging the crystalline lens. Direct measurements of lens shape and power were used to develop an age-dependent optical-mechanical model of the lens during accommodation. The study shows that the normal growth of the lens is a major contributor to the progressive loss of accommodation amplitude, independent of changes in the elastic properties of the lens. These findings suggest that accommodation can be restored by refilling the lens with a material having a uniform refractive index.
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Wilkins, Hugh Charles, and n/a. "A Structural Model of Satisfaction and Brand Attitude in Hotels." Griffith University. Griffith Business School, 2006. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20061023.160143.
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This thesis is about the customer experience in hotels. The thesis evaluates the customer experience in relation to the antecedents of behavioural loyalty. Behavioural loyalty is evaluated in relation to customer satisfaction, brand trust and brand attitude. Customer satisfaction is also evaluated in relation to the antecedents of hotel performance, service quality and perceived value. The broad research underpinning this research is: How do consumers perceive and relate to luxury and first class hotel brands? The hotel industry is a large and highly diverse industry that includes a wide range of property styles, uses and qualities (Chon & Sparrowe, 2000; Go & Pine, 1995; Olsen, 1996; Powers & Barrows, 1999). The industry covers the spectrum of small, medium and large enterprises (Brotherton, 2003; Jones, 2002) and makes a significant contribution to national and international economies. The research incorporated data collection in three stages. The first stage was a qualitative study of consumers who self selected as first class or luxury consumers. The data from the focus groups were used to develop items for inclusion in a survey instrument. The focus groups data, together with information gathered from a literature review, were used to develop scales across a number of hotel performance dimensions. In addition scales were included in the survey instrument on customer satisfaction, perceived value, brand trust, brand attitude and behavioural loyalty. The second stage of the research was a pilot study with the survey instrument being distributed to a convenience sample. The data collected at this stage were used to purify and refine the survey instrument. The final stage was data collected from consumers in a number of Australian hotels. The resultant data set comprised 693 completed and useable responses. The data were examined using exploratory and confirmatory factor analyses to confirm the hotel performance and other dimensions. The resultant dimensions showed good psychometric properties. A number of hypotheses were proposed in the thesis and examined using structural equation modelling. Although two hypotheses were rejected the resultant structural model showed strong relationships between the dimensions included. The research identified that service quality is a strong contributor to behavioural loyalty. The stronger pathway from service quality to behavioural loyalty was through customer satisfaction ( = 0.63) although the pathway through brand attitude ( = 0.22) was also significant. Both customer satisfaction and service quality had a significant effect on brand trust and service quality also influenced brand attitude. A number of recommendations for further research were made. These included the replication of this study in different geographic and industry contexts.
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Fonod, Robert. "Model-based Fault Diagnosis and Fault Accommodation for Space Missions : Application to the Rendezvous Phase of the MSR Mission." Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0199/document.
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Les travaux de recherche traités dans cette thèse s’appuient sur l’expertise des actionsmenées entre l’Agence spatiale européenne (ESA), l’industrie Thales Alenia Space (TAS) et le laboratoirede l’Intégration du Matériau au Système (IMS) qui développent de nouvelles générations d’unités intégréesde guidage, navigation et pilotage (GNC) avec une fonction de détection des défauts et de tolérance desdéfauts. La mission de référence retenue dans cette thèse est la mission de retour d’échantillons martiens(Mars Sample Return, MSR) de l’ESA. Ce travail se concentre sur la séquence terminale du rendez-vous dela mission MSR qui correspond aux dernières centaines de mètres jusqu’à la capture. Le véhicule chasseurest l’orbiteur MSR (chasseur), alors que la cible passive est un conteneur sphérique. L’objectif au niveaude contrôle est de réaliser la capture avec une précision inférieure à quelques centimètres. Les travaux derecherche traités dans cette thèse s’intéressent au développement des approches sur base de modèle de détectionet d’isolation des défauts (FDI) et de commande tolérante aux défaillances (FTC), qui pourraientaugmenter d’une manière significative l’autonomie opérationnelle et fonctionnelle du chasseur pendant lerendez-vous et, d’une manière plus générale, d’un vaisseau spatial impliqué dans des missions située dansl’espace lointain. Dès lors que la redondance existe dans les capteurs et que les roues de réaction ne sontpas utilisées durant la phase de rendez-vous, le travail présenté dans cette thèse est orienté seulementvers les systèmes de propulsion par tuyères. Les défaillances examinées ont été définies conformément auxexigences de l’ESA et de TAS et suivant leurs expériences. Les approches FDI/FTC présentées s’appuientsur la redondance de capteurs, la redirection de contrôle et sur les méthodes de réallocation de contrôle,ainsi que le FDI hiérarchique, y compris les approches à base de signaux au niveau de capteurs, les approchesà base de modèle de détection/localisation de défauts de propulseur et la surveillance de sécuritéde trajectoire. Utilisant un simulateur industriel de haute-fidélité, les indices de performance et de fiabilitéFDI, qui ont été soigneusement choisis accompagnés des campagnes de simulation de robustesse/sensibilitéMonte Carlo, démontrent la viabilité des approches proposéesThe work addressed in this thesis draws expertise from actions undertaken between the EuropeanSpace Agency (ESA), the industry Thales Alenia Space (TAS) and the IMS laboratory (laboratoirede l’Intégration du Matériau au Système) which develop new generations of integrated Guidance, Navigationand Control (GNC) units with fault detection and tolerance capabilities. The reference mission isthe ESA’s Mars Sample Return (MSR) mission. The presented work focuses on the terminal rendezvoussequence of the MSR mission which corresponds to the last few hundred meters until the capture. Thechaser vehicle is the MSR Orbiter, while the passive target is a diameter spherical container. The objectiveat control level is a capture achievement with an accuracy better than a few centimeter. The research workaddressed in this thesis is concerned by the development of model-based Fault Detection and Isolation(FDI) and Fault Tolerant Control (FTC) approaches that could significantly increase the operational andfunctional autonomy of the chaser during rendezvous, and more generally, of spacecraft involved in deepspace missions. Since redundancy exist in the sensors and since the reaction wheels are not used duringthe rendezvous phase, the work presented in this thesis focuses only on the thruster-based propulsionsystem. The investigated faults have been defined in accordance with ESA and TAS requirements andfollowing their experiences. The presented FDI/FTC approaches relies on hardware redundancy in sensors,control redirection and control re-allocation methods and a hierarchical FDI including signal-basedapproaches at sensor level, model-based approaches for thruster fault detection/isolation and trajectorysafety monitoring. Carefully selected performance and reliability indices together with Monte Carlo simulationcampaigns, using a high-fidelity industrial simulator, demonstrate the viability of the proposedapproaches
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Nannelli, Martina. "Competitiveness and Sustainability in the Sharing Economy Era. Opportunities and challenges from the Tourism and Hospitality Accommodation Industry." Doctoral thesis, Università degli studi di Trento, 2021. http://hdl.handle.net/11572/299831.
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The Sharing Economy is an innovative social, economic and technological paradigm which is shaping worldwide production and consumption patterns of many industries. Its strength relies on factors of competitiveness such as the use of idle capacity, temporary access to resources without transfer of ownership, the flexibility and adaptability of its models, and the participation of a growing number of players allowed by peer-to-peer digital platforms. From the management perspective, the conditions for lasting competitiveness lies on sustainability, the paradigm integrating the supply, demand, and technological dimensions in a holistic, or ecosystem, perspective. Tourism is among the industries making extensive use of sharing digital platforms and experiencing changes that foster the sustainability debate.
The PhD Thesis aims to investigate the relationships between competitiveness and sustainability in the tourism and hospitality accommodation industry in the Sharing Economy Era. Its investigation is multifaced and is addressed through three studies adopting a post-modernist perspective that builds on qualitative approaches and strategies for data collection and analysis.
The Part I of the Thesis explores the Sharing Economy concept’s evolution and the sustainability issues through an in-depth review of the literature. Results reveal the leading economic-technological evolution of the paradigm over the social one, and its dual links with sustainability in relation to the extensive use of peer-to-peer digital platforms. Therefore, the evolution of the Sharing Economy activities have shown that today competitiveness is built on the interactions of an ever-increasing number of actors and factors, both off-line and on-line, within a complex ecosystem for the creation of – shared – value. The tourism industry strongly challenges this relationship between extended competition and sustainability.
The Part II evaluates the competitiveness model and its evolution during the Sharing eTourism Era in the tourism and hospitality accommodation sector introducing an ecosystem perspective for the creation and distribution of shared value. Specifically, it investigates how the non-traditional and informal tourist services have affected the structure of the industry and have altered the competition among the actors, through semi-structured in-depth interviews. Results show that competitiveness is given by the balance among the complex interactions of internal and external ecosystem’s actors and factors. On a micro level this imply that businesses must adopts an ecosystem vision compensating for negative externalities which translate into the adoption of Business Models promoting sustainability for the creation of sustainable shared value. Therefore, the Part III investigates through the use of an illustrative case study how peer-to-peer digital platforms in the tourist accommodation service can boost profitability while strengthening economic, social and environmental sustainability by applying the innovative Business Model for Sustainability.
The research sheds light on the complex Sharing Economy literature and lays the theoretical foundations for the implementation of managerial strategies aimed at promoting extended sustainable competition-cooperation.
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Cozza, Vanessa Michelle. "Latino/as in Higher Education: Modes of Accommodation in First-Year Writing Programs." Bowling Green State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1306882228.
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MOUSTAGHFIR, ABDELKRIM. "Catalycite et accommodation dans un gaz de relaxation vibrationnelle. Modele numerique et etude experimentale." Aix-Marseille 1, 1991. http://www.theses.fr/1991AIX11337.
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Ce memoire presente une etude numerique et experimentale sur les phenomenes d'accommodation et de catalycite, dans le cas de la reflexion d'une onde de choc sur le fond d'un tube a choc. Les resultats d'origine numerique font apparaitre, l'influence des coefficients d'accommodation et du coefficient d'echange sur les profils dans la couche limite (temperature, ecart local a l'equilibre de l'energie de vibration), ainsi que leur influence sur les parametres parietaux tels que, les flux de chaleur propres a chaque mode, le flux total qui en resulte et enfin l'elevation de temperature parietale. Cette derniere grandeur est accessible experimentalement. D'autre part, les resultats experimentaux donnant l'evolution temporelle de l'elevation de temperature parietale en fond du tube a choc sont compares aux resultats obtenus numeriquement. Cette etude comparative nous a permis de deduire le coefficient d'accommodation dans le cas d'un gaz monoatomique argon , et les coefficients d'accommodation (translation-rotation et vibration), ainsi que le coefficient d'echange intermodes pour des gaz polyatomiques azote, gaz carbonique
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Gharsallaoui, Hajer. "Reconfiguration de lois de commande et accommodation active des modes de fonctionnement pour les systèmes plats." Thesis, Ecole centrale de Lille, 2010. http://www.theses.fr/2010ECLI0022/document.
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Les travaux de recherche entrent dans le cadre de la reconfiguration de lois de commande des systèmes dynamiques présentant divers modes de fonctionnement afin d’assurer les performances désirées. Deux approches d’accommodation ont été proposées pour la commande de ces systèmes dynamiques : une approche passive qui présente un régulateur à paramètres fixes ne garantissant pas les mêmes performances pour différents modes de fonctionnement et une approche active dans laquelle les paramètres du système de commande peuvent être mis à jour selon le mode de fonctionnement détecté. C’est cette deuxième approche basée sur une représentation multi-modèles du système qui a été retenue dans nos travaux.Les erreurs de modélisation correspondant aux variations de conditions de fonctionnement, sont dans ce cas détectées par un algorithme de détection et de localisation de variations de modes de fonctionnement. Il s’en suit une reconfiguration d’une loi de commande par platitude en utilisant le principe de commutation. Cette approche garantit la régulation et la poursuite d’une trajectoire de référence. Pour sa mise en œuvre, un banc de régulateurs, conçu par platitude, a été élaboré pour les modèles discrets plats obtenus autour des divers points de fonctionnement.La détection des modes de fonctionnement est effectuée par une génération de résidus en utilisant un ensemble d’observateurs de type Luenberger dont les gains sont calculés en utilisant l’outil LMI.L'étude de la stabilité ainsi que l'introduction de dispositifs d'anti-emballement liés à la commutation entre les régulateurs, ont été considérés dans l'approche proposéeThe work presented in this memory concerns the control reconfiguration of dynamical systems with variation of operating modes in order to ensure the desired performances. For the control of dynamic systems, two approaches of accommodation have been proposed. The passive approach presents a controller with fixed parameters that doesn’t ensure the same performance for different operating modes and an active approach in which the controller settings can be updated according to the variation of the detected operating mode. Our work has therefore focused on this second approach based on multi-models system representation. The modelling errors corresponding to the variations of operating conditions are detected in this case by detection and localization algorithm, consequently, a reconfiguration strategy based on flatness-based switching control is proposed. This approach guarantees the control and the tracking of a reference trajectory. In fact, we have synthesised a discrete flatness-based multi-controllers associated for each operating model obtained from different operating points. Detection of operating modes is done by a residual generation by using Luenberger observers which gains are calculated using the LMI tool. Study of the stability as well as the use of anti-windup devices related to switching between controllers; have been considered in the proposed approach
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Kmelnitsky, Vitaly M. "Automated On-line Diagnosis and Control Configuration in Robotic Systems Using Model Based Analytical Redundancy." Digital WPI, 2002. https://digitalcommons.wpi.edu/etd-theses/167.
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Because of the increasingly demanding tasks that robotic systems are asked to perform, there is a need to make them more reliable, intelligent, versatile and self-sufficient. Furthermore, throughout the robotic system?s operation, changes in its internal and external environments arise, which can distort trajectory tracking, slow down its performance, decrease its capabilities, and even bring it to a total halt. Changes in robotic systems are inevitable. They have diverse characteristics, magnitudes and origins, from the all-familiar viscous friction to Coulomb/Sticktion friction, and from structural vibrations to air/underwater environmental change. This thesis presents an on-line environmental Change, Detection, Isolation and Accommodation (CDIA) scheme that provides a robotic system the capabilities to achieve demanding requirements and manage the ever-emerging changes. The CDIA scheme is structured around a priori known dynamic models of the robotic system and the changes (faults). In this approach, the system monitors its internal and external environments, detects any changes, identifies and learns them, and makes necessary corrections into its behavior in order to minimize or counteract their effects. A comprehensive study is presented that deals with every stage, aspect, and variation of the CDIA process. One of the novelties of the proposed approach is that the profile of the change may be either time or state-dependent. The contribution of the CDIA scheme is twofold as it provides robustness with respect to unmodeled dynamics and with respect to torque-dependent, state-dependent, structural and external environment changes. The effectiveness of the proposed approach is verified by the development of the CDIA scheme for a SCARA robot. Results of this extensive numerical study are included to verify the applicability of the proposed scheme.
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Barnhart, Tei. "Conceptual frameworks and models for effective delivery of distance education : a planning aid tool derived from multiple case studies." Thesis, Loughborough University, 2002. https://dspace.lboro.ac.uk/2134/6837.
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Moravec, Ladislav. "Motel u Novomlýnských nádrží." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240242.
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Diploma thesis deals with the complex design documentation of newly-built motel near the Novomlýnských ponds with separate buildings. The building is situated near the D52 motorway in the cadastral Perná. The motel is designed for temporary accommodation, eating and recreation. It is a two-storey building with flat roof and without a basement. Besides the main building, there are also four bungalows. The building is designed with traditional building materials. The hotel is desingned for visitors with limited mobility and orientation.
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Nilagiri, Vinay Kumar. "Subjective measurement of the Stiles-Crawford effect." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/212371/1/Vinay%20Kumar_Nilagiri_Thesis.pdf.
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The Stiles-Crawford effect (SCE) is the differential effectivity of light entering the eye at different positions in the pupil. Its parameters are directionality (rate of change across the pupil) and peak location in the pupil. Using a spatial light modulation system, I investigated influences of field size, accommodation (focusing), and flicker frequency on the subjectively-measured SCE. SCE directionality increased with increase in field size, while peak location shifted temporally in the pupil with increase in focusing, but the SCE was not affected by a range of flicker frequencies. The field size results support a photoreceptor absorption model of the SCE.
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Hart, Linda Louise. "Accommodation : a novel." Thesis, University of Canterbury. Humanities, 2009. http://hdl.handle.net/10092/2550.
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Mazubane, Ewart Mphilisi. "A strategic entrepreneurial model to develop females for tourism related businesses." Thesis, Nelson Mandela Metropolitan University, 2009. http://hdl.handle.net/10948/1188.
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Since the inception of the new dispensation, entrepreneurship has been identified as one of the key enablers of economic participation. For this reason the government has established strategic institutions and mandated them to promote entrepreneurship in the country with the aim of increasing economic participation and entrepreneurial activities. One of the key and the fastest growing industries that have been identified as needing attention with regards to increasing participation of the women entrepreneurs is the tourism industry. There is now a noticeable growth of women entrepreneurs in this industry. They are found running bed and breakfasts (B&Bs) and conducting tours in urban areas as well as townships and rural areas. This is further evident if one looks at the value chain in the tourism sector. However, women entrepreneurs that are found in this sector are facing specific challenges that hinder their progress towards achieving sustainable businesses, especially those running or intending to run B&B businesses. Some of these challenges are sector related and some are just inherent to pursuing an entrepreneurial journey. The participation of women in the mainstream of entrepreneurship presents unique challenges as well. Women were never allowed to participate fully in the entrepreneurial activities. The latter still contributes to the challenges faced by women in their journey towards developing and operating sustainable businesses irrespective of the industry in which they operate in. Based on the above discussion, the main problem statement of this study is: To develop a strategic entrepreneurial model to enable female entrepreneurs to operate sustainable B&B businesses in the tourism industry.
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Winn, Barry. "Studies in binocular accommodation." Thesis, Glasgow Caledonian University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378073.
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A study of the binocular accommodation response is presented for normal and amblyopic observers to selected stimulus conditions using a binocular infra-red optometer and a commercially-available autorefractor. The work reviews the neural control of the near triad and discusses the historical development of models of mutual interaction between accommodation and convergence, presenting experimental evidence to support or refute each proposition. The basic characteristics of the accommodation response are reviewed along with the influencing factors. A central feature of this work is the evaluation of the correlation present between the eyes for both step-wise changes in target vergence and steady-state viewing. Reaction times for visually normal subjects were found to be similar to those found by previous workers and were independent of both size and direction of the step change. Response times for a mean step size of approximately 2.5D exhibited a marked degree of intersubject variability, particularly for the decreasing response and were step-size dependent. Eye dominancy was not found to be a significant factor in the overall response time. The binocular accommodation responses were found to have a high level of correlation to step-wise changes in target vergence. This in, itself, is perhaps not surprising in view of the anatomical similarities between the eyes and the relatively large dioptric changes induced. To obtain a clearer picture of the control of accommodation assessment of the microfluctuations was necessary. A high degree of correlation between amblyopic eyes and their fellow normal eyes is reported for both reaction and response times, although response times are longer than those for normal eyes. Reaction times for four subjects were not significantly different to those of the dominant eye. The subject presenting with the deepest amblyopia did have a significantly increased reaction time and a relationship with minimum angle of resolution is considered. Steady-state viewing shows the microfluctuations to have a high level of coherence, suggesting the control of accommodation to be at or above the point at which the IIIrd nerves are conjoint. Increasing target vergence causes an increase in the rms amplitude of the microfluctuations, binocular viewing not influencing the response characteristics. As target luminance decreased, rms values and low frequency drifts increased. Amblyopic eyes show an increase in the magnitude of the low frequency components of the microfluctuations for moderate to high stimulus vergences. The presence of different behaviour to that observed in normals supports a role for the microfluctuations. The response of amblyopic eyes to coloured stimuli results in an increase of the low frequency component to targets at the extremities of the visual spectrum, furthering the argument for a positive role for the fluctuations. The steady-state response to coloured stimuli differed from that found in normal eyes in that the appropriate response to overcome the chromatic interval was not observed for moderate to high stimulus vergences. The overall anomalous response could not use the additional information provided by coloured targets. Finally the detectibility of defocus was tested with sine waves and using signals derived from the microfluctuations. The threshold of detection for the microfluctuations is similar to that for sine waves, but is thought to be due to the presence of discontinuities and abrupt shifts in the response level. This adds support to Crane's(1966) hypothesis of 'accommodative saccades'.
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Rai, Gurjeet Kaur. "Accommodation and intraocular pressure." Thesis, Aston University, 2007. http://publications.aston.ac.uk/14645/.
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The relationship between accommodation and intraocular pressure (IOP) has not been addressed as a research question for over 20 years, when measurement of both of these parameters was less advanced than today. Hence the central aim of this thesis was to evaluate the effects of accommodation on lOP. The instrument of choice throughout this thesis was the Pulsair EasyEye non-contact tonometer (NCT) due principally to its slim-line design which allowed the measurement of lOP in one eye and simultaneous stimulation of accommodation in the other eye. A second reason for using the Pulsair EasyEye NCT was that through collaboration with the manufacturers (Keeler, UK) the instrument's operational technology was made accessible. Hence, the principle components underpinning non-contact lOP measures of 0.1mmHg resolution (an order of magnitude greater than other methods) were made available. The relationship between the pressure-output and corneal response has been termed the pressure-response relationship, aspects of which have been shown to be related to ocular biometric parameters. Further, analysis of the components of the pressure-response relationship together with high-speed photography of the cornea during tonometry has enhanced our understanding of the derivation of an IOP measure with the Pulsair EasyEye NCT. The NCT samples the corneal response to the pressure pulse over a 19 ms cycle photoelectronically, but computes the subject's lOP using the data collected in the first 2.34 ms. The relatively instantaneous nature of the lOP measurement renders the measures susceptible to variations in the steady-state lOP caused by the respiratory and cardiac cycles. As such, the variance associated with these cycles was minimised by synchronising the lOP measures with the cardiac trace and maintaining a constant pace respiratory cycle at 15 breathes/minute. It is apparent that synchronising the lOP measures with the peak, middle or trough of the cardiac trace significantly reduced the spread of consecutive measures. Of the 3 locations investigated, synchronisation with the middle location demonstrated the least variance (coeflicient of variation = 9.1%) and a strong correlation (r = 0.90, p = <0.001) with lOP values obtained with Goldmann contact tonometry (n = 50). Accordingly IOP measures synchronised with the middle location of the cardiac cycle were taken in the RE while the LE fixated low (L; zero D), intermediate (I; 1.50 D) and high (H; 4 D) accommodation targets, Quasi-continuous measures of accommodation responses were obtained during the lOP measurement period using the portable infrared Grand Seiko FR-5000 autorefractor. The lOP reduced between L and I accommodative levels by approximately 0.61 mmHg (p <0.00 I). No significant reduction in IOP between L and H accommodation levels was elicited (p = 0.65) (n = 40). The relationship between accommodation and lOP was characterised by substantial inter-subject variations. Myopes demonstrated a tendency to show a reduction in IOP with accommodation which was significant only with I accommodation levels when measured with the NCT (r = 0.50, p = 0.01). However, the relationship between myopia and lOP change with accommodation reached significance for both I (r = 0.61, p= 0.003) and H (r = 0.531, p= 0.0 1) accommodation levels when measured with the Ocular blood Flow Analyser (OBFA). Investigation of the effects of accommodation on the parameters measured by the OBFA demonstrated that with H accommodation levels the pulse amplitude (PA) and pulse rate (PR) responses differed between myopes and emmetropes (PA: p = 0.03; PR: p = 0.004). As thc axial length increased there was a tendency for the pulsatile ocular blood flow (POBF) to reduce with accommodation, which was significant only with H accommodation levels (r = 0.38, p = 0.02). It is proposed that emmetropes arc able to regulate the POBF responses to changes in ocular perfusion pressure caused by changes in lOP with I (r = 0.77, p <0.001) and H (r = 0.73, p = 0.001) accommodation levels. However, thc relationship between lOP and POBF changes in the myopes was not correlated for both I (r = 0.33, p = 0.20) and H (r = 0.05, p = 0.85) accommodation levels. The thesis presents new data on the relationships between accommodation, lOP and parameters of the OBFA,: and provides evidence for possible lOP and choroidal blood flow regulatory mechanisms. Further the data highlight possible deficits in the vascular regulation of the myopic eye during accommodation, which may play a putative role in the aetiology of myopia development.
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Dettner, Alexander. "Accommodation Of Religion : Arguments For The Permissibility And Desirability Of Accommodation Of Religion." Thesis, Uppsala universitet, Juridiska institutionen, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-192500.
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Sarotte, Camille. "Improvement of monitoring and reconfiguration processes for liquid propellant rocket engine." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS348/document.
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La surveillance et l'amélioration des modes de fonctionnement des systèmes propulsifs des lanceurs représentent des défis majeurs de l'industrie aérospatiale. En effet, une défaillance ou un dysfonctionnement du système propulsif peut avoir un impact significatif pour les clients institutionnels ou privés et entraîner des catastrophes environnementales ou humaines. Des systèmes de gestion de la santé (HMS) pour les moteurs fusée à ergols liquides (LPREs), ont été mis au point pour tenir compte des défis actuels en abordant les questions de sureté et de fiabilité. Leur objectif initial est de détecter les pannes ou dysfonctionnements, de les localiser et de prendre une décision à l’aide de Redlines et de systèmes experts. Cependant, ces méthodes peuvent induire de fausses alarmes ou des non-détections de pannes pouvant être critiques pour la sécurité et la fiabilité des opérations. Ainsi, les travaux actuels visent à éliminer certaines pannes critiques, mais aussi diminuer les arrêts intempestifs. Les données disponibles étant limitées, des méthodes à base de modèles sont essentiellement utilisées. La première tâche consiste à détecter les défaillances de composants et/ou d'instruments à l'aide de méthodes de détection et de localisation de fautes (FDI). Si la faute est considérée comme mineure, des actions de « non-arrêt » sont définies pour maintenir les performances de l'ensemble du système à un niveau proche de celles souhaitées et préserver les conditions de stabilité. Il est donc nécessaire d’effectuer une reconfiguration robuste (incertitudes, perturbations inconnues) du moteur. Les saturations en entrée doivent également être prises en compte dans la conception de la loi de commande, les signaux de commande étant limités en raison des caractéristiques ou performances des actionneurs physiques. Les trois objectifs de cette thèse sont donc : la modélisation des différents sous-systèmes principaux d’un LPRE, le développement d’algorithmes de FDI sur la base des modèles établis et la définition d’un système de reconfiguration du moteur en temps réel pour compenser certains types de pannes. Le système de FDI et Reconfiguration (FDIR) développé sur la base de ces trois objectifs a ensuite été validé à l’aide de simulations avec CARINS (CNES) et du banc d’essai MASCOTTE (CNES/ONERA)Monitoring and improving the operating modes of launcher propulsion systems are major challenges in the aerospace industry. A failure or malfunction of the propulsion system can have a significant impact for institutional or private customers and results in environmental or human catastrophes. Health Management Systems (HMS) for liquid propellant rocket engines (LPREs), have been developed to take into account the current challenges by addressing safety and reliability issues. Their objective was initially to detect failures or malfunctions, isolate them and take a decision using Redlines and Expert Systems. However, those methods can induce false alarms or undetected failures that can be critical for the operation safety and reliability. Hence, current works aim at eliminating some catastrophic failures but also to mitigate benign shutdowns to non-shutdown actions. Since databases are not always sufficient to use efficiently data-based analysis methods, model-based methods are essentially used. The first task is to detect component and / or instrument failures with Fault Detection and Isolation (FDI) approaches. If the failure is minor, non-shutdown actions must be defined to maintain the overall system current performances close to the desirable ones and preserve stability conditions. For this reason, it is required to perform a robust (uncertainties, unknown disturbances) reconfiguration of the engine. Input saturation should also be considered in the control law design since unlimited control signals are not available due to physical actuators characteristics or performances. The three objectives of this thesis are therefore: the modeling of the different main subsystems of a LPRE, the development of FDI algorithms from the previously developed models and the definition of a real-time engine reconfiguration system to compensate for certain types of failures. The developed FDI and Reconfiguration (FDIR) scheme based on those three objectives has then been validated with the help of simulations with CARINS (CNES) and the MASCOTTE test bench (CNES/ONERA)
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Larsson, Magdalena. "Beliefs regarding accommodation of dialects." Thesis, Linnéuniversitetet, Institutionen för språk och litteratur, SOL, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-16867.
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The aim of this paper is to investigate non-linguists' ideas about dialect accommodation. That is to say, the research questions concern people's beliefs about whether they accommodate their dialects to their interlocutors. In addition, one research question concerns people's suggestions as to why they adjust their speech and if differences between native and foreign languages can be found. The investigation was carried out as an informant survey and a total of 26 participants, between the ages 20 and 30, answered the questions. The data were analysed and discussed from a sociolinguistic and a sociopsychological perspective, with the theory CAT as a foundation for the interpretations. The results show that people believed they change their speech depending on conversation partner. This was thought of as subconscious behaviour and was mainly reflected upon afterwards. Furthermore, comments from the questionnaire concern changes in speech when talking to friends, when the interlocutor's dialect is distinct and when the informants visit a different geographical area. In addition, the informants have ideas about efficient communication when it comes to comprehensibility between the conversation partners' vocabularies as well as being on the same communicative level. The results from a native language accommodation situation and a foreign language accommodation situation showed similar ideas. That is to say, people's perceptions about accommodation did not differ much depending on what language they used.
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Flitcroft, Daniel Ian. "Sensory control of ocular accommodation." Thesis, University of Oxford, 1988. http://ora.ox.ac.uk/objects/uuid:9533e285-150f-4bc9-90d8-4a4a870a7f0e.
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Ransdell, Amanda OD. "Ciliary Muscle and Sustained Accommodation." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1427279533.
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Qin, Tongran. "Buoyancy-thermocapillary convection of volatile fluids in confined and sealed geometries." Diss., Georgia Institute of Technology, 2016. http://hdl.handle.net/1853/54939.
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Convection in a layer of fluid with a free surface due to a combination of thermocapillary stresses and buoyancy is a classic problem of fluid mechanics. It has attracted increasing attentions recently due to its relevance for two-phase cooling. Many of the modern thermal management technologies exploit the large latent heats associated with phase change at the interface of volatile liquids, allowing compact devices to handle very high heat fluxes. To enhance phase change, such cooling devices usually employ a sealed cavity from which almost all noncondensable gases, such as air, have been evacuated. Heating one end of the cavity, and cooling the other, establishes a horizontal temperature gradient that drives the flow of the coolant. Although such flows have been studied extensively at atmospheric conditions, our fundamental understanding of the heat and mass transport for volatile fluids at reduced pressures remains limited. A comprehensive and quantitative numerical model of two-phase buoyancy-thermocapillary convection of confined volatile fluids subject to a horizontal temperature gradient has been developed, implemented, and validated against experiments as a part of this thesis research. Unlike previous simplified models used in the field, this new model incorporates a complete description of the momentum, mass, and heat transport in both the liquid and the gas phase, as well as phase change across the entire liquid-gas interface. Numerical simulations were used to improve our fundamental understanding of the importance of various physical effects (buoyancy, thermocapillary stresses, wetting properties of the liquid, etc.) on confined two-phase flows. In particular, the effect of noncondensables (air) was investigated by varying their average concentration from that corresponding to ambient conditions to zero, in which case the gas phase becomes a pure vapor. It was found that the composition of the gas phase has a crucial impact on heat and mass transport as well as on the flow stability. A simplified theoretical description of the flow and its stability was developed and used to explain many features of the numerical solutions and experimental observations that were not well understood previously. In particular, an analytical solution for the base return flow in the liquid layer was extended to the gas phase, justifying the previous ad-hoc assumption of the linear interfacial temperature profile. Linear stability analysis of this two-layer solution was also performed. It was found that as the concentration of noncondensables decreases, the instability responsible for the emergence of a convective pattern is delayed, which is mainly due to the enhancement of phase change. Finally, a simplified transport model was developed for heat pipes with wicks or microchannels that gives a closed-form analytical prediction for the heat transfer coefficient and the optimal size of the pores of the wick (or the width of the microchannels).
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Coetzee, Anrike. "The future of student accommodation : the development potential of accommodation in the Hatfield Student Village." Diss., University of Pretoria, 2019. http://hdl.handle.net/2263/73329.
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Over the past decade, the demand for student housing in the Hatfield Student Village, situated between the Hatfield and Hillcrest campuses of the University of Pretoria, has grown to a point, where the demand greatly overshadows the supply. Local developers, who recognised the need for housing among students, have made great progress in filling this gap. It has come to a point, where the University of Pretoria has the second largest supply of student housing in South Africa, after the University of Cape Town.
This study has sought to determine whether there is still development potential for student housing in the Hatfield area, and also to develop a 10-year masterplan for the future development of accommodation in the Hatfield and Hillcrest areas.
Prominent development companies in the student-housing industry were contacted; and interviews were conducted with 8 high-ranking individuals in 8 different companies. The interviews determined the developers’ appetites for the further development of student accommodation in an area, which is already highly competitive. Interviews were also conducted with various role-players in Hatfield, such as the CEO of Hatfield CID, as well as prominent Estate Agents working in the area. Further data were collected on the various occupancy levels in the existing student accommodation, in order to determine the need for future development.
The results showed that developers have developed the area to supply about 11 315 beds to the market. With 4 178 beds in line to enter the market within the next 5 to 10 years, the supply will be much larger than the demand. Opportunity must be given to the economy to recover; and thereafter, further development of student accommodation must concentrate on providing units for low-income students.
A 10-year masterplan, divided into short-, medium- and long-term time periods, provides a potential road-map to follow, for the future of student accommodation in the Hatfield Student Village. The plan elaborates on future development and the type of development, which would ensure a successful student community for the University of Pretoria.Dissertation (MSc)--University of Pretoria, 2019.
Construction Economics
MSc (Real Estate)
Unrestricted
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Taylor, John. "Accommodation, refractive surgery and ocular aberrations." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/accommodation-refractive-surgery-and-ocular-aberrations(e457724c-b681-4957-ae7d-6ccdb2f0765d).html.
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The principal work in this thesis describes the investigation of the impact that alterations to ocular aberrations following refractive surgery have on the accommodative mechanism. A series of prospective studies were conducted with healthy adults (n=36) that had chosen to undergo refractive surgery at Manchester Royal Eye Hospital. A variety of monocular accommodative functions were assessed prior to surgery and then at one and three months following surgery on the same cohort of patients. Accommodative functions included amplitude of accommodation, accommodative facility (at 6m and 0.4m) including positive and negative response times, and accommodative stimulus-response functions. Dynamic accommodation responses were examined in a subgroup (n=10) at three months following refractive surgery and compared to an age-matched emmetropic control group (n=10) to evaluate differences in latency, amplitude, time constant and peak velocity of accommodation and disaccommodation. During the studies, ocular aberrations were concurrently measured to determine whether alterations to aberrations could help explain any observed changes in accommodative functions. Evaluation of visual, refractive and questionnaire outcome measures indicated that the patient cohort underwent successful surgery. Following surgery, significant alterations to a number of accommodative functions were discovered. Mean subjective ocular amplitude of accommodation increased by approximately 0.50D (p<0.05), mean stimulus-response function gradient decreased by approximately 10% (p<0.05) and distance facility rate increased by approximately 2-3 cycles/minute (p<0.05). Significant correlation was found between the change in accommodative stimulus-response function gradient, and the change in spherical aberration following surgery (p<0.05). Significant differences were also found in the parameters of accommodative dynamics, although some of these factors may be explained by refractive error differences between the refractive surgery patients (pre-operative myopes) and the emmetropic control group. The results suggest that alterations to aberrations following refractive surgery may be capable of influencing elements of the accommodation response. Additional studies were conducted to investigate the changes in aberrations during accommodation (n=31 subjects), and explore the contribution of the tear film (n=19 subjects) to higher order aberrations in eyes that have undergone refractive surgery. The results suggested that the rate of change in aberrations during accommodation is not affected by refractive surgery, but that the pattern of aberrations induced by post-blink tear film changes may differ in patients that have undergone refractive surgery. A further study is presented which investigated the form of the accommodative stimulus-response function to grating target of different spatial frequencies in groups of myopic (n=10) and emmetropic (n=10) participants recruited from among the staff and students at The University of Manchester. Both refractive groups appeared to show similar accommodative behavior, however the dominant feature of the data in both groups was between subject variation.
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Mucke, Sven. "Visual suppression during dynamic ocular accommodation." Thesis, Glasgow Caledonian University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.547426.
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Hudon, Tamara. "Bilingual Infants' Accommodation of Accented Speech." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/26163.
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Infant word recognition is sometimes hindered by variability in the speech input. Previous research has shown that, at 9 months, monolinguals do not generalize wordforms across native- and accented-speakers (Schmale & Seidl, 2009). In the current study however, it was predicted that bilingual infants would be advantaged in accommodating for accented speech due to experience with phonetic variability across their two phonological systems. It was also predicted that this hypothesized ability would be restricted to accommodating for an accent derived from a familiar language (e.g., French-English bilinguals would accommodate for French-accented English but not Mandarin-accented English), since this type of variability would be consistent with the language sounds to which infants were regularly exposed.
Study 1 set the experimental stage by identifying native and non-native speakers with similar voices, as perceived by a group of adults. This was done in order to restrict variability across speakers to differences in accent, rather than biological differences in voice (e.g., a higher or lower pitched voice). Following speaker selection, acoustic measurements of vowels and word stress placement were taken to compare native and non-native speakers and confirmed several expected deviations between native and accented speech. Study 2 tested the hypothesis that bilingual infants would be advantaged in accommodating for these deviations when the accent is derived from a familiar phonology. Using a headturn preference procedure (HPP), 9- and 13-month-old English-learning monolinguals and French-English learning bilingual infants were tested on their ability to recognize familiarized English wordforms across a native- and French-accented speaker. Bilinguals in both age groups succeeded in generalizing wordforms across speakers, however monolingual infants failed regardless of age. Study 3 tested whether bilinguals’ success would persist when the accented speaker’s first language was unfamiliar. Infants in this study failed as a group to generalize across native- and Mandarin-accented productions of English wordforms. However, bilinguals who received balanced exposure to their two languages performed better in accommodating for Mandarin accented speech than unbalanced bilinguals. This hints at a general ability to ignore irrelevant phonetic information, perhaps due to an advantage in cognitive control.
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Szostek, Nicola. "Assessment of ocular accommodation in humans." Thesis, University of Plymouth, 2017. http://hdl.handle.net/10026.1/9883.
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Accommodation is the change in the dioptric power of the eye altering the focus from distance to near. Presbyopia is the loss of accommodative function that occurs with age. There are many techniques used to measure accommodation, however, there is little consensus as to how clinical data should be collected and analysed. The overarching theme of this thesis is the in vivo examination of accommodation and how lifestyle can affect the onset of presbyopia. An open-field autorefractor with badal adaption was used to examine accommodative dynamic profiles under varying demands of vergence. From this data a new metric for assessing the time for accommodative change was derived. Furthermore this thesis describes a bespoke automated accommodative facility instrument that was developed to provide further assessment of accommodative speeds. Defocus curves are used for assessing accommodation and depth-of-focus; the work presented explores the use of non-linear regression models to define the most appropriate method of assessing defocus curves in phakic subjects, and pseudophakic subjects implanted with an extended depth-of-focus intraocular lens. Using an absolute cut-off criteria of +0.30logMAR improved the repeatability and reliability of the depth-of-focus metrics over a cut-off criteria relative to the best corrected visual acuity. A swept-source anterior segment optical coherence tomographer (AS-OCT) was used to image the morphology of the ciliary muscle during accommodation. The accuracy of ciliary muscle measurements was improved when using reference points on the sclera to align the AS-OCT scan. The use of a ciliary muscle area metric demonstrated poor repeatability and reliability when compared to the traditional assessment of muscle morphology via thickness measurements. Physiological ageing in the crystalline lens occurs in line with ageing in other structures in the body. The methods for assessing accommodative function examined in previous chapters, were used to examine whether lifestyle factors which affect the rate of systemic ageing, such as smoking, also affect accommodative function. Although being a current smoker and having greater central adiposity was associated with a slower time for accommodative change, further research is required before these findings can be applied to the target population.
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Arey, Dale Simon. "Accommodation for the peri-parturient sow." Thesis, University of Aberdeen, 1990. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU032002.
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Prior to giving birth, sows are normally confined in crates. One of the current aims in pig production is to develop an alternative farrowing system in which the sows are unconfined and grouped together. The aim of the new system is to improve the welfare of the sow and litter whilst maintaining high levels of productivity. Four studies were conducted to document the nest building and social behaviour of sows so that the system can be designed to suit their needs. The fifth study compared the productivity of unconfined individual and grouped sows with confined sows. Study 1. Six sows were housed in a pen which contained a sand floor and straw dispenser. Nine and a half hours before farrowing the sows displayed rooting, pawing and straw carrying and removed 23 kg straw to build a nest with hollow, straw lining and nest rim. Six sows were presented with similar nests. Nest building behaviour was affected by feeding behaviour. Study 2. Sixteen sows were presented with a hollow (H), a mattress (M), a nest box (B) which represented the 3 nest features and a control (C). Farrowing site preference was (H) 6, (M) 6, (B) 4 and (C) 0. In trial 2, (C) was replaced by a straw area (S), all 16 sows farrowed in (S) when it contained 4.5-18 kg straw. At 2.25 kg preference was (H) 1, (M) 3, (B) 1, (S) 3. Nest building behaviour was not affected by the amount of straw in (S).Study 3. Four previously confined and 3 unconfined sows were housed in a pen which included a straw (S), a central food (F) and a control (C) area. Entry into (S) and (C) was contingent on 10 panel presses. Food was delivered into (F) every 2 hours. The sows pressed the panel for (S) more than (C). Nest builidng behaviour was affected by feeding behaviour. Confined sows tended to show more behaviour associated with the straw. In trial 2, 5 sows were housed in pen which included a straw (S), a central (C) and a food (F) area. Cost of entry into (S) and (F) was gradually increased. Food was delivered into (F) every 45 mins. The fall in work rates for straw and food were similar as the cost was increased. The work rate for straw was increased 24 hours before farrowing. Study 4. Twenty-two sows were paired with an unfamiliar conspecific in pens which contained 2 strawed lying areas. As farrowing approached, the sows spent less time lying together and the aggressive behaviour of 12 dominant prepartal sows increased significantly. The level of aggression was significantly reduced in 11 dominant prepartal sows paired with unfamiliar conspecifics in modified pens and between 9 pairs of pre-partal sows which were familiar with each other. Sows were observed to lie together at farrowing and to farrow in more than one lying area. Study 5. Appetite and piglet mortality was compared for 43 sows in straw pens, 51 sows housed with pen-mates in straw pens and 50 sows in farrowing crates. Appetite was not reduced during the periparturient period or affected by pen type. There was no difference in the number of piglets which died during the first 24 hours after farrowing in the 3 pen types. Sows in farrowing crates tended to have more stillborn piglets.
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Farmer, Henry Keith. "Managing maintenance of multiple domestic accommodation." Thesis, Loughborough University, 2003. https://dspace.lboro.ac.uk/2134/34238.
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Buildings rarely fail within a short time of commissioning; most become unsatisfactory gradually, over a period of many years, as the design becomes obsolete and/or inadequate maintenance and improvements fail to keep pace with demand. Maintenance work is thus necessary to keep a building in an acceptable minimum condition. The industrialised building methods much used in the 1960s were frequently innovative and, at that time, unproven methods of construction. When these are added to the list of 'traditional build' failure contributors, the need for additional and regular maintenance is increased. Various factors contribute to domestic accommodation buildings ceasing to be Satisfactory—to fail in their purpose of providing a safe, warm and dry environment for the occupants. To the layperson, bad workmanship by the builders, poor quality materials, poor design and inadequate maintenance are common causes for complaint. This research investigated the cost of maintenance for buildings of multiple domestic accommodation, methods used to organise maintenance planning and budgeting, and considered whether the use of industrialised building methods had affected that cost. The current and anticipated future use of Planned Preventative Maintenance, together with other management methods, as tools for minimising maintenance cost is also examined. A method for introducing a system of planned preventative maintenance that is specifically tailored to individual buildings from a common pattern was developed as an output of this research. 'Designing out' the need for maintenance requires an understanding of maintenance activity cost centres (i.e. where does the money go and what elements of maintenance account for the greatest expenditure?). The way that building professionals perceive potential maintenance cost requirements is therefore investigated and comparison made with actual costs for the same elements of maintenance.
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Suryawardani, I. Gusti Ayu Oka. "Tourism leakage of accommodation in Bali." Thesis, Paris 1, 2015. http://www.theses.fr/2015PA010071/document.
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Le tourisme est le fer de lance de l'économie balinaise. Mais, les fruits de cette économie du tourisme ne bénéficient pas à toutes les classes de la société balinaise. Cela est dû, entre autres, au manque à gagner lorsque cette industrie importe par exemple des produits ou des services pour répondre aux besoins des touristes (alimentation pour la restauration par exemple). Le calcul du manque à gagner pour l'économie balinaise n’a jamais été fait auparavant. Pour cela, cette recherche est nécessaire. Les objectifs de la recherche étaient : de calculer le manque à gagner pour l'économie balinaise dans le secteur du logement pour les touristes en micro-économie (niveau industriel) ; d'estimer le manque à gagner pour le tourisme balinais dans le secteur de l'hébergement touristique en macroéconomie (au niveau provincial) ; d'évaluer l'impact de la subvention gouvernementale et la réduction des importations dans l' industrie du tourisme, les opportunités d'emploi et la distribution des revenus ; d'évaluer la perception et le choix des touristes internationaux face aux offres de produits importés et locaux, et aussi d'évaluer l'opinion des touristes sur le constat : est-ce que les dépenses des touristes pendant leur voyage à Bali bénéficient à la société balinaise ? ; et d'évaluer les opinions des gestionnaires des hôtels sur l'utilisation des produits importés et des produit locaux pour la consommation des touristes ; de créer une stratégie afin de minimiser le manque à gagner dans le secteur du tourisme pour l'économie balinaise. La recherche est basée sur les approches quantitatives et qualitatives. Les données primaires ont été recueillies par la méthode du sondage sur quatre destinations touristiques, à savoir : Kuta, Nusa Dua, Sanur et Ubud, auprès d'un échantillon de 79 hôtels selon la méthode de probabilité proportionnelle à la taille qui est divisée en trois échantillons en grappes : hôtels classés 1, 2 et 3 étoiles ; hôtels classés 4 & 5 étoiles et hôtels privés (non-chain) ou appartenant à une chaine hôtelière (chain) ; hôtels non-classés. Nombre de répondants 600 touristes internationaux qui étaient en vacances à ce moment-là. Le calcul du manque à gagner dans l'analyse micro a été mené selon la méthode d'Unluonen et. al. (2011), tandis que l'analyse macro a été faite selon la méthode de Thorbecke (1988) en utilisant l'approche de la matrice de comptabilité sociale (MCS) de la province de Bali de l'année 2010. La perception et le choix des touristes internationaux vis-à-vis des produits importés et locaux ont été analysé selon le logiciel JMP tandis que les stratégies de la minimisation du manque à gagner dans l'économie touristique balinaise ont été créées selon la méthode de l'ISM (interpretive Structural Modelling). [...] Les touristes internationaux choisissent de façon significative les produits locaux et ils sont prêts à dépenser leur argent au bénéfice des populations locales. Les gestionnaires des hôtels sont prêts à utiliser les produits locaux tant que l’offre est suffisante pour remplacer les produits importés. Les stratégies pour minimiser le manque à gagner pour le tourisme à Bali : optimiser les potentiels des produits locaux ; développer l'agriculture et l' élevage, réduire les produits importés pour la consommation des touristes, augmenter l'exportation des produits locaux, augmenter la qualité des produits locaux ainsi que la qualité des ressources humaines locales, renforcer la société locale, inciter le gouvernement à mettre en œuvre une politique de minimisation du manque à gagner dans l'économie touristique, limiter les investissements étrangers dans le secteur du logement touristique, stabiliser les fluctuations des taux de change, augmenter le rôle du Ministère des affaires étrangères, du ministère de l'industrie, du Ministère du commerce ainsi que le rôle du Ministère du tourisme et de l'économie créative afin de réduire ledit manque à gagnerTourism has become the leading economic sector in Bali Province of Indonesia. However, the economic impacts of tourism have not been convinced to be full y beneficial for Balinese community. One of the reasons is tourism leakage that occurs when the industry imports both products and services to support tourism industry in Bali. So far, the amount of tourism leakage in Bali has not been calculated yet. Therefore, there is a need to ascertain the current amount of leakage in Bali tourism. The objectives of the study are: (i) to calculate the amount of tourism leakage from accommodation sector in Bali at micro (industrial) level; (ii) to calculate the amount of tourism leakage from accommodation sector in Bali at macro (regional) level; (iii) to evaluate the impacts of government subsidies and import reduction by accommodation sector on tourism leakage, job opportunity and income distribution; (iv) to evaluate the perception and preference of foreign tourists on imported and local products as well as the willingness of foreign tourists to spend their money to benefit of Balinese people; (v) to evaluate the points of view of hotel managers related to imported and local products as well as their willingness in reducing the use of imported product and (vi) to develop strategies in minimizing tourism leakage in accommodation in Bali. Research was designed through quantitative and qualitative approaches. Data was collected by using survey method at four main tourist destinations in Bali, namely: Kuta, Nusa Dua, Sanur and Ubud. There were 79 hotels selected based upon probability proportional to size sampling method which consists of three clusters namely 1,2,3 Star-rated, 4&5 Star-rated either chain and non-chain and Non Star-rated hotels. The number of respondents was 600 foreign tourists were selected as respondents. Calculation of tourism leakage on micro analysis was undertaken by using a method developed by Unluonen, et. al. (2011), meanwhile, on macro analysis was carried out by using a method proposed by Thorbecke ( 1988) which was based on the Social Accounting Matrix (SAM) of Bali 2010. Perception and preference of foreign tourists on imported and local products were analyzed by using JMP program, meanwhile, Interpretative Structural Modelling (ISM) was undertaken to develop strategies. The results show that based on the micro analysis, the highest tourism leakage of accommodation sector in Bali is at 4&5 Star-rated chain hotels (51.0 %), followed by 4&5 Star-rated non-chain hotels (22.7 %), 1,2&3 Star-rated hotels (12.0 %), Non-star rated hotels (8.8 %), and with the average leakage of 18.8 %. Based on macro analysis, tourism leakage of accommodation sector in Bali are as follow: (i) Leakage of Non Star-rated hotels is 2.0 %; (ii) Leakage of 1,2&3 Star-rated hotels is 15.7 %; (iii) Leakage of 4&5 Star-rated non-chain hotels is 7.1 %, (iv) Leakage of 4&5 Star-rated chain hotels is 55.3%; and (v) Average leakage of all types of accommodation is 19.5%. Foreign tourists significantly look for local products and are willing to spend their money for Balinese people. Hotel managers are willing to use local product as long as local products are available to substitute the imported products. Strategies for minimization tourism leakage are optimizing the potential of local products, develop agriculture and livestock; reduce the use of imported products for tourists, improve quality of local products and human resources, empower community, urge government to develop and implement supporting policies in minimizing tourism leakage, establish policy on restriction of foreign investment on accommodation in Bali, improve the role of Ministry of Foreign Affairs, Ministry of Industry, Ministry of Trade and Ministry of Tourism and Creative Economy. 7 Ps of marketing mix on service: product, price, place, promotion, people, process and physical evidence need to be implemented in order to support sustainable tourism in Bali
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Aldossari, Hussain Mubarak D. "Accommodation effects on peripheral ocular biometry." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/95486/1/Hussain%20Mubarak%20D_Aldossari_Thesis.pdf.
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The effect of near work on the biometric properties of the eye, including the eye’s length and the thickness of the posterior vascular layer were investigated. Short-sighted eyes had greater increases in length and greater thinning of the vascular layer when focused on close objects than did normally-sighted eyes. These changes occurred across the horizontal meridian of the eye and were greatest at the posterior pole. These ocular effects of focusing may partly explain the influence of close work on development of short-sightedness.
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Wu, Monica S. "Family Accommodation in Adults with Obsessive-Compulsive Disorder: Psychometric Properties of the Family Accommodation Scale - Patient Version." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5407.
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Family accommodation is a salient construct within the context of obsessive-compulsive disorder (OCD) and occurs in a large majority of affected individuals and their families. Accommodating behaviors can manifest in various ways, including participation in the patient's rituals, modifying everyday routines, facilitating compulsive behaviors, or providing reassurance. It has been repeatedly linked to negative outcomes, such as attenuated treatment response, increased obsessive-compulsive symptom severity, higher levels of family distress, and lower levels of functioning. As such, it is of significant clinical importance to have a standardized measure that is able to be used in research and clinical practice.
The Family Accommodation Scale for Obsessive-Compulsive Disorder (FAS) was the initial attempt at a measure to systematically assess for family accommodation in patients with OCD, with different clinician-rated and self-reported versions completed by the relative arising thereafter. However, to date, there is not a patient-reported version of the instrument. Existing measures focus on reports from the relative (e.g., the patient's significant other, parent), overlooking information from the patient themselves. Additionally, adult patients with OCD often present to clinical services alone, frequently making it impractical to obtain information from their relative. As such, it is important to have a standardized patient-reported measure to examine the accommodating behaviors.
The present study sought to evaluate the psychometric properties of the Family Accommodation Scale for Obsessive-Compulsive Disorder - Patient Version (FAS-PV). A large majority of the participants (88.5%) endorsed at least one type of accommodating behavior in the previous week. Provision of reassurance and waiting for completion of compulsions were the most frequently reported behaviors, while helping with personal tasks and making excuses/lying due to OCD-related impairment were the least frequently endorsed. The FAS-PV demonstrated good internal consistency and test-retest reliability, as well as good convergent/divergent validity. The FAS-PV did not significantly differ from the relative-reported measure of family accommodation in terms of internal consistency or mean scores. Ultimately, the FAS-PV demonstrated sound psychometric properties and utility in assessing family accommodation from the patient's perspective.
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Gunnarsson, Nathalie. "Competitive, Accommodative or Neither? : An Examination of two Swedish Parties Competitiveness while in Opposition and Support Party Status." Thesis, Linnéuniversitetet, Institutionen för statsvetenskap (ST), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-90999.
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This research aims to contribute to the knowledge gap about opposition and support parties’ competitive behaviour in minority situations where no party have a majority in the parliament. Two Swedish parties - the Centre Party and the Left Party - will be examined to answer the two overarching research questions. Namely, 1) how does the competitive behaviour of parties vary in relation to a party’s role as a support party or opposition party? And 2) does the result support the cartel party thesis or the model of classic opposition? The competitive behaviour was measured in regards to counter proposals, standpoints and reservations on the governmental propositions. This was done through a quantitative content analysis of committee reports during four terms of office. The results indicate that both parties were more competitive during their time in opposition compared to in support status. This supports the model of classic opposition and rejects the cartel party thesis.
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Ljubimova, Darja. "Numerical modelling of the human eye accommodation /." Stockholm : Department of Mechanics, Royal Institute of Technology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4078.
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Clarke, Jacqueline R. "Sustainable tourism : marketing of farm tourist accommodation." Thesis, Oxford Brookes University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261392.
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Khosravi, Bahram. "The influence of ocular astigmatism on accommodation." Thesis, University of Manchester, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312103.
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Rabie, E. P. "Biometry of the crystalline lens during accommodation." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378316.
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Paolinelli, Irene. "Reasons for the choice of sustainable accommodation." Master's thesis, Instituto Superior de Economia e Gestão, 2020. http://hdl.handle.net/10400.5/20656.
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Mestrado em MarketingEste estudo visa compreender as razões de escolha de um alojamento sustentável. Os conceitos explorados são os antecedentes para o comportamento turístico sustentável, nomeadamente quais as atitudes, motivações, valores e estilo de vida influenciam as escolhas de viagens sustentáveis. Adota-se uma abordagem de investigação exploratória e uma investigação qualitativa mono método. Os dados são recolhidos através de entrevistas em profundidade semi-estruturadas a viajantes que escolheram alojamentos sustentáveis durante as suas viagens. Além disso, foram entrevistados também alguns gestores de estabelecimentos turísticos sustentáveis localizados em Portugal, especialmente nas proximidades de Lisboa. Pretende-se determinar quais são os fatores que mais influenciam esta escolha e definir o significado de um alojamento sustentável. O estudo procura contribuir para a área académica do consumo sustentável e do comportamento sustentável do consumidor no campo do turismo. Para além disso, fornece insights para o sector hoteleiro com o intuito de aperfeiçoar a oferta dos serviços e as estratégias de comunicação integradas.
This study aims to understand the reasons for the choice of sustainable accommodation. The concepts explored are the antecedents towards sustainable tourist behaviour, namely which attitudes, motivations, values, lifestyle influence sustainable travel choices. It adopts an exploratory research approach and a mono method qualitative research design. Data are collected through semi-structured in-depth interviews to travellers staying in sustainable accommodation and to managers of sustainable tourist establishments based in Portugal, in particular, nearby the Lisbon Area. It is intended to determine which factors influence this choice the most and to define sustainable accommodation. The study seeks to contribute to the academic area of green consumption and sustainable consumer behaviour in the tourism field. Moreover, it provides insights to the hospitality sector to focus better on the services offer and integrated communication strategies.
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Randhawa, Parminder. "Pharmacological and physiological manipulation of ocular accommodation." Thesis, Aston University, 2017. http://publications.aston.ac.uk/30401/.
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The primary aim of this thesis was to investigate in-vivo changes to ocular morphology during ocular accommodation, with particular attention to ciliary muscle changes, using pharmacological agents and physiological stimuli. To determine the optimum target for accommodation studies, accommodative responses to different stimuli were investigated. Insignificant differences in accommodative responses to a letter target and Maltese cross were found. Anterior Segment Optical Coherence Tomography (AS-OCT) and semi-automated software were used for in-vivo investigation of ciliary muscle morphology. As expected, anti-muscarinic agents reduced the accommodative amplitude, the greatest effect evident with cyclopentolate hydrochloride 1%, which was, in turn, associated with a reduced forward movement of the ciliary muscle, possibly due to the restricted movement of radial and longitudinal fibres. Pilocarpine nitrate 2% induced a contractile shortening and anterior thickening of the ciliary muscle in both pre-presbyopic and presbyopic eyes. However, pilocarpine does not seem to be a super-stimulus for accommodation. Comparison between cyclopentolate and pilocarpine ciliary muscle morphology further supported the concept that anterior movement of ciliary muscle mass is essential to elicit higher accommodative amplitudes. Ciliary muscle asymmetry was identified between horizontal and vertical meridians. The findings confirmed a longer ciliary muscle in axial elongated eyes, however, only within the temporal, nasal, and superior muscle quadrants. Nevertheless, during accommodation, anterior thickening and contractile shortening of the muscle was evident for all four quadrants. The effect of accommodation on posterior eye conformation revealed a homogenous elongation of the posterior pole, with the greatest expansion occurring along the inferior-nasal quadrant, rather than the visual axis. The possibility of a vitreous role in accommodation is discussed. The studies presented herein suggest a forward movement of ciliary muscle mass is necessary for accommodation. Further research is required to establish whether a mechanical restriction occurs to the muscle with increasing age, resulting in presbyopia. Moreover, investigations are required to explore the variation in ciliary muscle morphology in eyes with ametropia, as well as the likely role of the vitreous in accommodation.
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Vial, Vazquez Andrea Celeste. "A Role-Based Theory of Prejudice Accommodation." Thesis, Yale University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10957350.
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This dissertation developed and tested a role-based framework drawing from role theory to understand how external factors contribute to the spread of bias in organizations. Using experimental social psychological methods, the twelve studies in this dissertation investigated why other people's prejudices can sometimes influence individuals' decisions and behaviors due to the demands of the decision maker role. Role theory posits that there are certain expectations associated with specific roles, and the roles that people occupy can determine their attitudes and behaviors. Across studies, participants placed in a decision-making role in charge of hiring selections accommodated the prejudices of relevant third parties in their decisions (i.e., the "third-party prejudice effect''). Specifically, consistent with the proposed model, in the studies described in Chapter 2, individuals in charge of selection decisions were significantly less likely to select a woman when a relevant third party was prejudiced against women. Chapter 3 extended this inquiry to novel, fictional groups, generalizing the third-party prejudice effect beyond the context of gender bias.
According to a role-based framework, concerns relevant to the decision maker role become highly salient in contexts of third-party prejudice, motivating those in charge of hiring selections to accommodate this prejudice in order to accomplish role-relevant goals. In particular, in the context of hiring selections, decision makers accommodate third-party prejudice without coercion because they engage in two types of considerations, focused (a) on maximizing performance (i.e.. task-focused concerns). and (b) on avoiding conflict or facilitating relations among the parties involved (i.e., interpersonal concerns). These task-focused and interpersonal concerns are relevant to the decision maker role and reflect well-established distinctions between instrumental and socioemotional dimensions of group processes. This proposed mechanism was experimentally supported. revealing that task-focused and interpersonal concerns significantly mediated the effect both in the context of gender prejudice (Chapter 2) as well as in a novel groups context (Chapter 3). Furthermore, in Chapter 2, experimentally reducing role-relevant concerns by manipulating task-focused considerations significantly reduced the accommodation of third-party prejudice against women.
In line with the notion that roles impact behavior above and beyond individual-level attitudes and beliefs, participants in two studies accommodated prejudice against women in their selections regardless of their personal endorsement of modern sexism and traditional gender stereotypes (Chapter 2). Participants similarly accommodated third-party prejudice against groups about which they knew very little, in contexts in which pre-existing biases or the endorsement of cultural stereotypes had little bearing on their selections (Chapter 3). Moreover, consistent with the proposition that roles shape behavior more strongly than social identity, participants across studies accommodated third-party prejudice in their decisions even when such prejudice was directed toward a social category in-group. A role-based framework can illuminate the institutional factors that produce social disparities, and can contribute to a growing understanding of the reasons why members of underrepresented groups sometimes appear to treat each other poorly in organizational contexts.
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Lossing, Laura Ashley Eisele. "Changes in Ciliary Muscle Thickness with Accommodation." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306365302.
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Zehner, Gregory F. "Prediction of anthropometric accommodation in aircraft cockpits /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488203857251563.
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Hogan, Robert E. "Aspects of tonic accommodation and tonic vergence." Thesis, Aston University, 1985. http://publications.aston.ac.uk/14586/.
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Under conditions of reduced visual stimulation, the systems of accommodation and vergence tend towards physiological resting states that are intermediate within their functional range. The terms tonic accommodation (TA) and tonic vergence (TV) are used in the study to describe these stimulus-free, intermediate adjustments and to represent the systems as being in a state of innervational tonicity. The literature relating to TA and TV and the various experiments of this thesis are reviewed. Methodology has been developed enabling the determination of TA and TV under conditions of total darknessl laser optometry for TA and ~ernier-alignment for TV. The thesis describes a series of experiments designed to investigate various aspects of TA and TV, and their role in ametropia, binocular vision and their adaptation to sustained visual tasks. Measurements of TA were also utilised to investigate the effect of various autonomic effector drugs on the ciliary muscle. The effects of ethanol on binocular function are shown to be directly proportional to the .initial level of TVJ which is itself unaffected. These results support the concept of TV as the reference point for normal vergence responses. The results of the pharmacological investigations indicate the presence of a small but significant, beta-receptor mediated inhibitory sympathetic input to the ciliary muscle, and that the wide distribution in TA is a consequence of inter-observer variations in parasympathetic, rather than sympathetic tone. Following interaction with visual tasks of t5mins duration, the levels of TA and TV are found to be biased in the direction of, and proportional to, the task position: except during near-task viewing where the task-to-TA stimulus-distance exceeds 1.5D (for TA) and 3.5deg (for TV). Under these conditions the expected level of bias is attenuated, Adaptive models are discussed, proposing TA and TV as the reference points of the accommodative and vergence system.