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This article focuses on British migration to the Lot, a rural, inland department in the southwest of France. It first emphasizes the diversity among these lifestyle migrants by proposing a typology based on the position migrants occupy in the life course at the time of migration, identifying three different types of Britons living permanently in rural France: the family migrants, retirement migrants, and mid-life migrants. Each group of migrants hold in common their reasons for leaving Britain, the circumstances of their migration, and their position in the life course. The article then examines how the context of their lives before migration influences life in the Lot. In particular, it analyses the role of practical considerations in residential choice and degrees to which the migrants integrate into the local French population. By understanding the context of the migrants' lives before migration, certain aspects of their lives in the Lot are illuminated, helping to fragment stereotypes of expatriate populations and challenge the dominance of retirement migration within related literature. [ABSTRACT FROM AUTHOR]

Abstract: Launcher trajectory optimization is a complex task, especially when considering the specific problems arising in the study of reusable launch vehicles. Part of the difficulty comes from the different characteristics of the trajectory arcs which make up the vehicle''s mission (constraints and controls may not be the same). Another difficulty is the necessity, in some cases, of a global optimization between ascent and re-entry phases (branching optimisation). Finally, optimization tools devoted to this task should be polyvalent and robust, as the studies of reusable launch vehicles usually cover many different concepts, and also many different trajectory cases (such as abort scenarios). The purpose of this paper is to present different approaches used in France by CNES and ONERA to solve optimal control problems in the context of launcher trajectory optimization. These approaches, which are powerful implementations of classical optimization methods, were designed to cover the needs for both expendable and reusable launchers trajectory calculation. The first optimization tool presented is OPTAX, which uses an indirect shooting method. The second and third tools presented are CNES''s ORAGE and ONERA''s FLOP/OLGA, which use two different variants of the gradient method. The paper describes the equations and methodology behind these tools, and also presents their advantages and drawbacks. [Copyright &y& Elsevier]