Trip packing in petrol stations replenishment

This paper considers a generalized version of the trip packing problem that we encountered as a sub-problem of the petrol stations replenishment problem. In this version we have to assign a number of trips to a fleet composed of a limited number of non-identical tank-trucks. Each trip has a specific duration, working time of vehicles is limited and the net revenue of each trip depends on the truck used. The paper provides a mathematical formulation of the problem and proposes some construction, improvement and neighbourhood search solution heuristics. A set of benchmark problem instances is created in a way that reflects real-life situations and used to analyse the performance of the proposed heuristics. A real-life case is also used to further assess the proposed heuristics.     

An ordinal approach to the study of intergenerational opportunities for standard of living: the case of Latin America

This paper looks at the intergenerational transmission of opportunities for standard of living in Latin America. It proposes to study this question on the basis of an ordinal approach. This ordinal approach borrows recent ideas on the way to compare opportunity sets, that is, to rank matrices giving, for example, the distribution of individuals by level of education of their parents and the standard of living (income) of the group to which they belong. Such comparisons are based on the use of the concepts of rank and Generalized Lorenz Dominance. The empirical illustration is based on the data of the 2006 Latinobarómetro survey which covered 18 Latin American countries and the standard of living of individuals (children) was derived from an algorithm allowing one to compute the order of acquisition of durable goods and access to services.     

加拿大与美国都市圈内政府治理差异分析

本文探讨地方公共机构尤其是地方行政机构如何改变其结构和手段,以应对新的地区化和都市化的挑战。通过分析35个美国和加拿大的城市群,评估政府机构在多大程度上采用了怎样的方法去规划、实施和监督都市化政策,并重点研究都市圈机构和都市圈的财税政策。     

Age-specific mortality trends in France and Italy since 1900: Period and cohort effects

Although France and Italy currently exhibit very similar expectations of life, their mortality patterns by age and sex are not the same. The differences were much greater at the beginning of the century than they are now. Graphical presentation of the data since 1900 by age, period and birth cohort is used to explore in detail the differences in trends and to bring out, in particular, differences between the two countries in period and cohort effects. In addition to providing more details on well-known period effects — the secular decline in mortality in both countries (with Italy largely ‘catching up’ with France), and the immediate effects of the world wars — similarities and differences in cohort effects are also apparent. The two countries exhibit clear differences not only in terms of immediate casualties of the wars, but also in terms of the long-term impact of unfavourable wartime living conditions on the cohorts most affected.