Because of their high strength to weight ratio, stiffened steel plates are often used in light structures where plates are placed into compression. The stability of steel plates stiffened with longitudinal tee-shaped stiffeners and subjected to uniaxial compression or combined axial compression and out-of-plane bending formed the basis for this research project. The research was conducted to develop a simple approach to assess the post-buckling behaviour of stiffened steel plates and provide a limit states design procedure that accounts for the post-buckling stability in the assessment of the resistance factor. The behaviour of stiffened plates was investigated using a finite element model that had been validated through comparison with test results. An exhaustive parametric study, including 1440 finite element analyses, was conducted to investigate the strength and behaviour of stiffened steel plates. A virtual work model was developed to explain the effect of the formation of a plastic hinge mechanism on the post-buckling strength and behaviour. Combined with the numerical results, the theoretical model confirms that the plastic hinge mechanism can cause a sudden loss of capacity. The required lateral deflection for a plastic hinge development can be calculated using the virtual work model for prediction of the unstable behaviour. Based on a better understanding of the behaviour of stiffened steel plates, a set of design equations were developed to calculate the strength of stiffened steel plate subjected to compression in the direction of the stiffener and out-of-plane bending. The proposed design equations were compared with current design guidelines through a comparison of the design approaches with the finite element analysis results. The proposed method showed much better accuracy than the current design approaches. A reliability analysis was conducted to provide appropriate resistance factors for limit states design. Due to the complexity of the design formulas, the Monte Carlo simulation technique was used to generate the statistical distributions of the predicted strength. The second-moment method was used to calculate the resistance factors for different values of safety index. The resistance factor varied from 0.90 to 0.65 for values of safety index from 2.5 to 4.5, respectively. / Structural Engineering

Communication technologies have become a central characteristic of workplace functioning. The literature has suggested that the use of these technologies fundamentally changes the manner in which team members interact. The present study sought to reorganize previous research on the impact of virtuality on team emergent states and behavioral processes to elucidate how different degrees of team virtuality shape team functioning, and to investigate the manner in which these relationships differ according to team type, team membership stability, and publication year. Findings from 174 studies (total number of teams = 9204; total N approximately 26,050) suggest that there is not a strong relationship between team virtuality and emergent states and behavioral processes. However, moderator analyses revealed that a reliance on highly virtual tools may be most detrimental to action teams and ad hoc teams. Moreover, findings demonstrate that the degree to which virtuality shapes team transition and action process may be changing over time.

The bistable spherical compliant mechanism (BSCM) is a novel device capable of large, repeatable, out-of-plane motion, characteristics that are somewhat difficult to achieve with surface micromachined microelectromechanical systems. An improved pseudo-rigid-body model (PRBM) to predict the behavior of the BSCM is presented. The new model was used to analyze seven different versions of the device, each with a different compliant joint length. The new model, which adds torsion, is compared with a finite element analysis (FEA) beam model. The new model more closely approximates the results yielded by FEA than previous models used to analyze the BSCM. Future work is needed to quantify stress-stiffening interactions between bending and torsion. Both FEA and the current models show that increasing the length of the compliant segment decreases the amount of force required to actuate the device.

This thesis improves a previous kinematic analysis and develops the elastic portion of the analysis of a curved compliant beam. This analysis is used to develop a Pseudo-Rigid-Body Model for the curved compliant beam. The Pseudo-Rigid-Body Model consist of kinematic and elastic parameters which can be used to simplify the computation of the large deflections of the beam as it undergoes spherical motion. The kinematic parameters that are developed are the characteristic radius, Gamma*length, the parametric angle coefficient, c_theta, and the kinematic parametrization limit, Capital_theta_max(Gamma). The elastic parameters developed are the stiffness coefficient, K_theta, and the elastic parameterization limit, Capital_theta_max(K). Additionally, curve fit parameters are developed which enable the calculation of the stress in curved beam as it deflects.

D. Tech. Informatics / In the world of information and communications technology (ICT), collaboration plays a central and significant role towards development and economic growth. Collaboration is relevant for all spheres, starting with individuals, organizations, private businesses, governments, and specifically research institutions which focus on research and innovation. In the academia, e-collaboration has become part of the survival strategy and is also essential to ensure continuity, competitiveness, growth and maturity. ARIs (Academic and Research Institutions) must plan on how e-collaboration is applied and improved in organizations. The main research objective for this study was to propose an e-Collaboration Maturity Model for ARIs. In support of this four secondary objectives were listed as follows: To investigate collaboration initiatives and technology amongst ARIs; To understand the driving forces and challenges towards Collaboration amongst ARIs; To explore the themes of e-Collaboration; To review maturity and assessment models.

No description available.

Newly qualified educators in Botswana face many challenges not least of which occurs when they are posted to rural schools a distance from other teachers and information resources. The Government of Botswana has committed itself to enhancing the ICT infrastructure for use in both the economic and educational endeavours of the country. Research conducted in first world countries show that Communities of Practice can take place in a virtual environment and that these can facilitate knowledge sharing and management. This research was conducted to investigate if a Virtual Community of Practice (VCoP), guided by the educational theories of Constructivism and Connectivism, could facilitate information and knowledge sharing among art teachers in dispersed location in the Botswana context. Using Reeves and Hedberg’s (2003) Development Research model, 13 art teachers, who were located in different parts of the country, participated in knowledge sharing through a Virtual Community of Practice. This study analysed the specific needs of art educators, interrogated the literature for best practices, formed a VCoP, and analysed how participants used it and reports on their comments The research findings indicate that educators would be enthusiastic about the use of such a facility if there was a perceivable benefit especially in breaking down the geographical induced communication barriers that they face at the moment. The research does not propose the replacement of existing face-to-face workshops, meetings and other communication fora, but rather suggests a VCoP can complement them by allowing discussions to continue beyond such meetings. It is contended that a carefully structured and supported VCoP can improve information and knowledge sharing significantly among educators and other stakeholders in Botswana. / Thesis (M.A.)-University of KwaZulu-Natal, Durban, 2009.

Dissertation (Ph.D.)--Auburn University, 2006. / Abstract. Includes bibliographic references.

Thesis (M.App.Psy.)--University of Waikato, 2008. / Title from PDF cover (viewed February 25, 2009) Includes bibliographical references (p. 59-71)

Thesis (Ph.D.) - Carleton University, 2005. / Includes bibliographical references (p. 433-448). Also available in electronic format on the Internet.