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The shoulder joint is a multi-axis synovial ball and socket joint, by having a loose connection it provides a wide degree of freedom; however this means the joint lacks robustness and is prone to damage most commonly from shoulder dislocations. A rotator cuff tear causes major problems in allowing the arm to be lifted beyond a 90˚ abduction position. It is common that this insufficiency aggravates arthritis problems that may have occurred due the rotator cuff tear problem. The study focuses on investigating, describing and quantifying the implant geometric properties to evaluate the joint contact characteristics and use the outcome in redesign the implant. The investigation presents results of finite element analysis on a heavy loading condition on a Verso (reverse) shoulder implant which is validated using experimental data on the same prosthesis. The results are validated within a 5% error margin. A Verso implant is modelled using MIMICS (materialise) and imported into ABAQUS (Simulia, Providence, USA) to analyse the distribution of stress, strain and displacement across the Humerus and Scapula. Details of interaction, boundary conditions, loads and material properties are all obtained from research and applied to the model to portray realistic behaviour. The resulting stress, strain and displacement from this simulation are indicated to show the magnitude and distribution across the entire bone region. This validates the benefits of a Verso implant compared to conventional and long stemmed reverse shoulder implants, as well as provide a basis from which improved designs can be built upon and allow further accurate methods to be developed in analysing shoulder implants effectively.

This thesis deals with a theoretical and an experimental exploration of squeeze film levitation (SFL) of light objects. The investigations aimed to find the important design parameters controlling this levitation mechanism and also to suggest an alternative way to implement SFL. The study, through computer modelling and experimental validation, focused on Poisson's contraction effect for generating SFL. A finite element model (ANSYS) was verified by experimental testing of five different plate designs. Each plate was subjected to a uniaxial plain stress by an arrangement of two hard piezoelectric actuators (PZT) bonded to the bottom of the plate and driven with DC or AC voltages. It was observed that pulsation of a dimple or crest shaped elastic deformation along the longitudinal axis in the central area of the plate was created because of Poisson's contraction. This Poisson's effect generated the squeeze-film between the plate and the levitated object. The separation distance between a floating lightweight object and the plate was analysed using computational fluid dynamics (ANSYS CFX) through creation of a modelling model for the air-film entrapped between the two interacting surfaces - a typical three-dimensional fluid-solid interaction system (FSI). Additionally, the levitation distance has been experimentally measured by a Laser Sensor. A satisfactory agreement has been found between model predictions and experimental results. Two levitation systems, one based on a horn transducer (Langevin type) and the other one in the form of a plain rectangular plate made of Aluminium and firmly fastened at both ends with a surface-mounted piezoelectric actuator, were compared in this thesis. Both devices were based on SFL mechanism. Evidently, the performances of both designs were greatly influenced by the design structure and in particular by the driving plate characteristics such as plate size and geometry as well as the driving boundary conditions. To this end, physical experiments were carried out and it was found that the device utilising horn-type transducer yields better levitation performance. Ultimately, the research explained the confusion between three approaches to non-contact levitation through literature review and also pointed out some essential parameters like piezoelectric actuators location, material of the driving structure, coupled-field between the actuators and the driving structure and the fluid-solid interface that was existed between the excited plate and the levitated object.

Negative interpersonal workplace behaviours are an important but relatively infrequently studied occupational-stressor. The present research investigated the connection between these behaviours and employee well-being. This work had two main goals. The first goal was to provide greater insight into when and why social interactions at work can be harmful to employee well-being. Consistent with this goal, theory and research were reviewed, and results from two field studies were presented suggesting that (1) disrespect is an important characteristic of interpersonal workplace events that can explain detriments to employee well-being, and (2) both individual and contextual moderators are relevant in this process. In a first study, disrespectful leader behaviours were shown to negatively relate to employee well-being independent of demanding, production-focused leader behaviours. In a second study, perceived disrespectfulness mediated the relationship between exposure to negative interpersonal behaviour and well-being; workplace norms, social support, control-related self-beliefs, and negative affectivity moderated associations within the mediation sequence. Given the importance placed on objective measurement methods in the occupational stress literature, the inherent difficulties in measuring social stressors objectively, and the widespread use of self-report instruments in the literature, the second main goal of this work was to approach greater objectivity in the measurements of self-reported negative interpersonal workplace interactions. A number of approaches were used toward this end, including the development of a more objective self-report measure of interpersonal workplace behaviours, as well as the use of aggregate variables and the investigation of moderated relations within multilevel frameworks. Implications of this work and directions for further research are discussed.

Negative interpersonal workplace behaviours are an important but relatively infrequently studied occupational-stressor. The present research investigated the connection between these behaviours and employee well-being. This work had two main goals. The first goal was to provide greater insight into when and why social interactions at work can be harmful to employee well-being. Consistent with this goal, theory and research were reviewed, and results from two field studies were presented suggesting that (1) disrespect is an important characteristic of interpersonal workplace events that can explain detriments to employee well-being, and (2) both individual and contextual moderators are relevant in this process. In a first study, disrespectful leader behaviours were shown to negatively relate to employee well-being independent of demanding, production-focused leader behaviours. In a second study, perceived disrespectfulness mediated the relationship between exposure to negative interpersonal behaviour and well-being; workplace norms, social support, control-related self-beliefs, and negative affectivity moderated associations within the mediation sequence. Given the importance placed on objective measurement methods in the occupational stress literature, the inherent difficulties in measuring social stressors objectively, and the widespread use of self-report instruments in the literature, the second main goal of this work was to approach greater objectivity in the measurements of self-reported negative interpersonal workplace interactions. A number of approaches were used toward this end, including the development of a more objective self-report measure of interpersonal workplace behaviours, as well as the use of aggregate variables and the investigation of moderated relations within multilevel frameworks. Implications of this work and directions for further research are discussed.

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Historically, “offender”-focused discourses have dominated the field of criminology while overlooking those family members who become subject to justice intervention by virtue of their familial bonds. In this qualitative study, unstructured interviews were conducted with eight nuclear family members of criminalized persons in Ontario and Quebec. Participant accounts reveal that the interviewed family members self-imposed significant moral and legal responsibilities for their relatives following criminal justice intervention and simultaneously experienced negative role re-evaluation driven by feelings of guilt, failure, and self-blame. Participants’ inherent lack of control over their criminalized relatives’ behaviours and the criminal justice system’s decisions exacerbate negative impacts of criminalization on non-criminalized relatives’ self-concepts. This lack of control increases the stress of criminal justice intervention while straining family resources. When relatives are justice-involved for prolonged period, the family becomes stuck in a constant state of stress and uncertainty, which may have lasting consequences on the family if left unmanaged. Criminal justice intervention as a disruptive event then reconfigures the family in ways that often leave lasting impacts on nuclear family relationships. This thesis engages with Boss’ (1999, 2006) theory of Ambiguous Loss to analyze participants’ experiences and demonstrate the consequences of criminalization on various nuclear family members in a Canadian context. To mitigate certain limitations of Boss’ (1999, 2006) theory, criminal justice intervention is first defined as a disruptive event that transforms family members’ known realities into threatening and uncertain environments. This thesis then explores the stress and strain that justice intervention places upon the family and applies the theory of Ambiguous Loss to understand criminalization as a source of ambiguous loss. Further, this thesis expands the scope of Boss’ (1999) theory beyond the experiences of certain populations (i.e. children of incarcerated parents) and discovers the limitations of this theory in the context of criminological research. It also opens the door for future research to apply this theory to criminalized populations.

Recently, the railway pavement structure system, as an integral part of the transport infrastructure, has been under fast development in some countries such as China, Turkey, and some European Union countries, particularly for the use of high-speed trains. In designing and constructing the railway pavement structure, it is necessary to take into account the infrastructure demand of the High-Speed Railway Lines (HSRL). Compared to traditional railway trains, HSRL can cause more significant problems to the ballast or base layer of commonly used ballasted railway pavements. The deteriorated ballast or base layer may further result in substructure degradation that may cause safety issues and catastrophic accidents. As a consequence, heavy goods or high-speed trains will affect railway efficiency. As a countermeasure, a railway pavement structure may be reinforced by geosynthetic materials in the ballast or base layer. In the literature, however, there is still a need to quantify the effect of geosynthetic materials, geogrid in particular, on the mechanical responses of railway pavement structures to HSRL loads, which is necessary knowledge in supporting the selection of appropriate material and placement location of geogrid. Therefore, the goal of this study is to investigate how a geogrid reinforcement layer can change the essential characteristics of a ballasted railway pavement structure, with focus on the material type and placement location of geogrid that can help minimize the rate of deterioration of the railway pavement structure system. This research attempts to validate the advantage of geogrid reinforcement through numerical simulation in a realistic railway setting. All technical literature on the use of geogrids in the railway system has been studied. A three-dimensional (3D) finite element model was constructed for the numerical simulation, in which three different types of geogrid placed at two different locations (i.e., within the ballast layer, between the ballast and the sub-ballast layer) within a railway pavement structure were analyzed under a range of vertical wheel loads. Therefore, four possible applications of geogrid reinforcement systems (G0: no-reinforcement; G1: reinforced with geogrid having the lowest density and Young’s modulus; G2: reinforced with geogrid having the intermediate Young’s modulus and density; G3: reinforced with geogrid having the highest density and Young’s modulus) were modeled to represent different situations in ballasted railway systems. Railway mechanical responses, such as vertical surface deflection, maximum principal stress and strain, and maximum shear stress were analyzed and compared among the four geogrid reinforcement scenarios and under four vertical wheel load levels (i.e., 75, 100, 150 and 200 kN). The advantages of such geosynthetics in ballast are indicated by result difference in the mechanical responses of railway pavement structures due to the use of different geogrid materials. The results also show that the reinforced structures have lower vertical surface deflection, lower maximum shear stress at the interface of sleeper and ballast, and maximum principal stress at the bottom of the ballast layer than a non-reinforced railway pavement structure. Consequently, the addition of geogrid into the ballast layer, and between the ballast and sub-ballast layer has been shown to reduce critical shear and principal stresses and vertical surface deflection in a ballasted railway pavement structure. Besides that, the results of the analysis confirm that geogrid reinforced layers exhibit higher resistance to deformation than the non-reinforced layers.

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