529 research outputs found
Family finance and doorstep trading: social and economic wellbeing of elderly Ghanaian female traders
Ghana's female traders frequently "gift" their working businesses to their daughters or other junior female relatives as a means of providing for their old age. This occupational gifting customarily ensures the ageing trader social and economic support in her later years as she is assured of an exchange of financial and other forms of assistance. However, the gifting of the working business to a daughter does not mean the end of the woman's trading career. As she grows older the trader scales down the level of her business activities and frequently ends up trading with little capital on the doorstep of her home. This career structure provides the ageing woman with a strong economic and social definition amongst her kin and facilitates her active integration into the household unit. Continued trading inhibits social marginalization. Fifty elderly women traders were interviewed about the practice of occupational gifting. A key finding was that although the practice is still widespread it is in decline. Alternative ways of ensuring the active integration of elderly women into the contemporary African urban household are considered
Acceptability with general orderings
We present a new approach to termination analysis of logic programs. The
essence of the approach is that we make use of general orderings (instead of
level mappings), like it is done in transformational approaches to logic
program termination analysis, but we apply these orderings directly to the
logic program and not to the term-rewrite system obtained through some
transformation. We define some variants of acceptability, based on general
orderings, and show how they are equivalent to LD-termination. We develop a
demand driven, constraint-based approach to verify these
acceptability-variants.
The advantage of the approach over standard acceptability is that in some
cases, where complex level mappings are needed, fairly simple orderings may be
easily generated. The advantage over transformational approaches is that it
avoids the transformation step all together.
{\bf Keywords:} termination analysis, acceptability, orderings.Comment: To appear in "Computational Logic: From Logic Programming into the
Future
Refining Nodes and Edges of State Machines
State machines are hierarchical automata that are widely used to structure complex behavioural specifications. We develop two notions of refinement of state machines, node refinement and edge refinement. We compare the two notions by means of examples and argue that, by adopting simple conventions, they can be combined into one method of refinement. In the combined method, node refinement can be used to develop architectural aspects of a model and edge refinement to develop algorithmic aspects. The two notions of refinement are grounded in previous work. Event-B is used as the foundation for our refinement theory and UML-B state machine refinement influences the style of node refinement. Hence we propose a method with direct proof of state machine refinement avoiding the detour via Event-B that is needed by UML-B
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