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Increasingly tighter budgets, changes in government role/function, declines in staff resources, and demands for increased accountability in the transportation field have brought unprecedented challenges for state transportation officials at all management levels. Systematic methodologies for effective management of a specific type of infrastructure (e.g., pavement and bridges) as well as for holistically managing all types of infrastructure assets are being developed to approach these challenges. In particular, the intrinsic characteristics of highway system make the use of multi-objective optimization techniques particularly attractive for managing highway assets. Recognizing the need for effective tradeoff tools and the limitations of state-of-practice analytical models and tools in highway asset management, the main objective of this dissertation was to develop a performance-based asset management framework that uses multi-objective optimization techniques and consists of stand-alone but logically interconnected optimization models for different management levels. Based on a critical review of popular multi-objective optimization techniques and their applications in highway asset management, a synergistic integration of complementary multi-criteria optimization techniques is recommended for the development of practical and efficient decision-supporting tools. Accordingly, the dissertation first proposes and implements a probabilistic multi-objective model for performance-based pavement preservation programming that uses the weighting sum method and chance constraints. This model can handle multiple incommensurable and conflicting objectives while considering probabilistic constraints related to the available budget over the planning horizon, but is found more suitable to problems with small number of objective functions due to its computational intensity. To enhance the above model, a hybrid model that requires less computing time and systematically captures the decision maker's preferences on multiple objectives is developed by combining the analytic hierarchy process and goal programming. This model is further extended to also capture the relative importance existent within optimization constraints to be suitable for allocations of funding across multiple districts for a decentralized state department of transportation. Finally, as a continuation of the above proposed models for the succeeding management level, a project selection model capable of incorporating qualitative factors (e.g. equity, user satisfaction) into the decision making is developed. This model combines k-means clustering, analytic hierarchy process and integer linear programming. All the models are logically interconnected in a comprehensive resource allocation framework. Their feasibility, practicality and potential benefits are illustrated through various case studies and recommendations for further developments are provided. ; Ph. D.

L'engouement soudain et récent à l'égard de l'union libre avant le mariage au Canada et dans les pays occidentaux industrialisés est un phénomène sans précédent. Cet article étudie le rôle de l'union de fait en tant qu'élément déterminant de la transition vers un premier mariage. Les données historiques de l'Enquête sociale générale de 1990 ont révélé que l'union de fait retarde le moment du premier mariage d'environ 26% chez les femmes et de 19% chez les hommes. Cette caractéristique reste importante et signifiante après correction du facteur de sélectivité relative à l'union de fait. L'analyse prouve également qu'il existe un phénomène d'autosélection en faveur de l'union de fait. Il semble que l'expérience de l'union libre en tant que telle influe sur les attitudes des individus à l'égard du mariage et diminue leur propension à se marier.The recent surge in premarital cohabitation in Canada and other Western industrial countries is unprecedented. This paper examines the role of cohabitational experiences as a determinant of the transition to first marriage. Using union history data from the 1990 General Social Survey, I find that cohabitational experiences delay the timing of first marriage by about 26% for women and 19% for men. This effect remains substantial and significant after I correct for the selectivity of cohabitation. The analysis also reveals evidence of selection into cohabitation. It appears that the experience of cohabiting itself affects the attitudes of individuals toward marriage and decreases their propensity to marry.

Previous research has indicated that premarital cohabitation decreases marital stability. This study examined the role of premarital cohabitation as a determinant of cohabitation after marital disruption. The author proposed that people who cohabited with their first spouse prior to marriage have a greater propensity to cohabit after marital disruption than people who did not cohabit before their first marriage. Event history analysis of the postmarital union experiences of women and men from the Canadian 1990 Family and Friends Survey (FFS) supports this proposition. It was found that the hazard rate of postmarital cohabitation was over 50% higher for premarital cohabitants than for noncohabitants. This was the case for both women and men. The implications of these results are discussed.

AbstractMulticulturalism promises equality and tolerance, yet racialized minorities in Canada continue to report experiences of discrimination. As Canada becomes increasingly culturally and racially diverse, it is important to understand what this discrimination means for sense of belonging in Canada. Using ordinary logistic regressions, we examine the effects of ethnocultural and racial discrimination on sense of belonging. Relying on a theoretical framework of the Rejection/Identification and Rejection/Disidentification models, we test the impacts of discrimination on national sense of belonging and on in‐group sense of belonging. We further examine the differential effects of discrimination on sense of belonging for white and non‐white Canadians. We find that discrimination negatively impacts both national and in‐group sense of belonging among both non‐white and white Canadians, although the impact is stronger among racialized minorities. Thus, we argue that discrimination reduces sense of belonging in Canada generally, but is more damaging to those who already occupy a marginalized social position. These findings have implications for our understanding of multiculturalism in Canada.

Throughout much of the developed world, increasing numbers of women are delaying their entry into motherhood. In this study we examine the determinants of first-births among women who were childless at aged 30 and older, and test a number of hypotheses based upon three perspectives that may explain this phenomenon. While we are concerned primarily with the effects of education and employment, we also include a number of other explanatory variables that may have impact upon delayed childbearing. Our results suggest that both school enrolment and employment tend to reduce the odds of a woman becoming a mother, while level of education increases the likelihood. We also find a significant interaction effect between education and employment, and speculate that how a woman utilizes her education determines how employment affects her chances of becoming a mother.

The substantial number of childless elderly in Canada and the United States raises important concerns about the nature of their family support, as well as their psychological well‐being. Although the (mixed) effects of childlessness on the mental health of the elderly are well documented in the literature, little is known about the social distribution of psychological distress and depression within this population: how well the childless elderly live, the status of their mental health, and what factors affect their psychological well‐being are all crucial questions that remain unanswered. This paper utilizes Pearlin et al.'s (1981) stress process model to examine psychological distress and depression among the childless elderly. Our empirical analysis uses a nationally representative sample of childless individuals aged 55 and over (N= 2,311) from the 1996‐1997 National Population Health Survey (NPHS), and generalized linear model (GLM) techniques. Generally, our results support the stress process model. We find that individual‐level stressors exert a strong and consistently negative impact on psychological distress and depression. We also find significant buffering effects of (perceived) social support.