An Africa strategy for IIMI

Irrigation management / Policy / Africa

Private irrigation in Sub-Saharan Africa: regional Seminar on Private Sector Participation and Irrigation Expansion in Sub-Saharan Africa, Accra, Ghana, 22-26 October 2001

Irrigation management / Privatization / Irrigated farming / Financing / Irrigation systems / Gender / Women / Government managed irrigation systems / Farmer managed irrigation systems / Rice / Horticulture / Technology transfer / Pumps / Drip irrigation / Filtration / Capacity building / Urban agriculture / Poverty / Water users associations / Agricultural credit

Indicators of the performance of irrigation water distribution systems

Water distribution / Performance evaluation / Indicators / Equity

Changing Bases: Multistage Optimization for Matroids and Matchings

This paper is motivated by the fact that many systems need to be maintained continually while the underlying costs change over time. The challenge is to continually maintain near-optimal solutions to the underlying optimization problems, without creating too much churn in the solution itself. We model this as a multistage combinatorial optimization problem where the input is a sequence of cost functions (one for each time step); while we can change the solution from step to step, we incur an additional cost for every such change. We study the multistage matroid maintenance problem, where we need to maintain a base of a matroid in each time step under the changing cost functions and acquisition costs for adding new elements. The online version of this problem generalizes online paging. E.g., given a graph, we need to maintain a spanning tree $T_t$ at each step: we pay $c_t(T_t)$ for the cost of the tree at time $t$, and also $| T_t\setminus T_{t-1} |$ for the number of edges changed at this step. Our main result is an $O(\log m \log r)$-approximation, where $m$ is the number of elements/edges and $r$ is the rank of the matroid. We also give an $O(\log m)$ approximation for the offline version of the problem. These bounds hold when the acquisition costs are non-uniform, in which caseboth these results are the best possible unless P=NP. We also study the perfect matching version of the problem, where we must maintain a perfect matching at each step under changing cost functions and costs for adding new elements. Surprisingly, the hardness drastically increases: for any constant $\epsilon>0$, there is no $O(n^{1-\epsilon})$-approximation to the multistage matching maintenance problem, even in the offline case

Irrigated agriculture in Southeast Asia beyond 2000: Proceedings of a Workshop held at Langkawi, Malaysia, 5 to 9 October 1992

Water management / Irrigated farming / Institution building / Technology / Training / Policy / Research / Education / Social aspects / Economic aspects / Sustainability / Priority setting / South East Asia / Indonesia / Malaysia / Philippines / Thailand

Water management in a tank cascade irrigation system in Sri Lanka: First seasonal report of TARC-IIMI Joint Project 1991/1992 Maha Season

Water management / Tank irrigation / Small scale systems / Irrigation management / Crop-based irrigation / Water balance / Water conveyance / Sri Lanka / Thirappane

Developmental biographies of Olympic super-elite and elite athletes – a multidisciplinary pattern recognition analysis

This multidisciplinary study used pattern recognition analyses to examine the developmental biographies of 16 Great British Olympic and World Champions (‘Super-Elite’) and 16 matched international athletes who had not won major medals (‘Elite’). Athlete, coach and parent interviews (260 total interview hours) combined in-depth qualitative and quantitative methods. A combination of demographics, psychosocial characteristics, coach and family relationships, practice, competition, and performance development discriminated Super-Elite from Elite athletes with > 90% accuracy. Compared to Elite athletes, Super-Elite athletes were characterized by: (1) An early critical negative life experience in close proximity to significant positive sport-related events; (2) higher relative importance of sport over other aspects of life, stronger obsessiveness/perfectionism, and sport-related ruthlessness/selfishness; (3) conjoint outcome and mastery focus, and use of counterphobic and/or ‘total preparation’ strategies to maintain/enhance performance under pressure; (4) coaches who better met their physical and psychosocial needs; (5) coming back after severe performance setbacks during adulthood, and career ‘turning points’ leading to enhanced determination to excel; (6) more pronounced diversified youth sport engagement, and prolonged extensive sport-specific practice and competitions; and (7) continued performance improvement over more years during adulthood, eventually attaining their (first) gold medal after 21 ± 6 practice years. The findings are discussed relative to potential causal interactions and theoretical implications

The Great British Medalists Project: A Review of Current Knowledge on the Development of the World’s Best Sporting Talent

The literature base regarding the development of sporting talent is extensive, and includes empirical articles, reviews, position papers, academic books, governing body documents, popular books, unpublished theses and anecdotal evidence, and contains numerous models of talent development. With such a varied body of work, the task for researchers, practitioners and policy makers of generating a clear understanding of what is known and what is thought to be true regarding the development of sporting talent is particularly challenging. Drawing on a wide array of expertise, we address this challenge by avoiding adherence to any specific model or area and by providing a reasoned review across three key overarching topics: (a) the performer; (b) the environment; and (c) practice and training. Within each topic sub-section, we review and calibrate evidence by performance level of the samples. We then conclude each sub-section with a brief summary, a rating of the quality of evidence, a recommendation for practice and suggestions for future research. These serve to highlight both our current level of understanding and our level of confidence in providing practice recommendations, but also point to a need for future studies that could offer evidence regarding the complex interactions that almost certainly exist across domains