MICROFICHE REFERENCE LIBFUUW - Cd3wd.com

162of other water ladder designs, with a variety of prime movers and transmissionsneeds to be studied also to better evaluate its application andprovide criteria for selection.With such studies as the two above serving as basic examples, similarresearch into the performance of other water lifters needs to be conducted.As mentioned throughout this paper, data on many devices is either nonexistentor available in only a limited quantity and quality for a scatteredor narrow range of capacities, heads, and designs. A survey study isinitially needed to determine the present levels of usage and possiblebenefits of modification for each type of water lifter. In this manner,a priority for detailed performance studies can be made to organize athorough research program. Through the review of references for this paper,some specific lifters which have a lack of data, but would appear to benefitfrom such studies include: (a) the mot, particularly the circular motdriven by other than animal power; (b) the counterpoise lift and doon,with emphasis on counterweight placement and weight to minimize manualeffort without the present trial-and-error construction techniques; (c)the picottah; (d) the bellows (as partially undertaken by IRRI); and (e)all screw and wheel devices with particular attention to presenting performanceas a function of size, power, and speed of operation (i.e., rpm).Among the missing data on most of these devices is cost. Some basic costparameters such as cost of construction or initial purchase, and of operation,need to be established to provide a practical component for the selectionprocess (Section 5.3).These studies must include a thorough program encompassing a surveyof user's needs, design, testing and evaluation. Such a program wasundertaken by Battelle Institute on its AID hand pump and serves as a good