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Now showing 1 - 6 of 6
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    Sensory contribution from exracts of botanicals to distilled alcoholic beverages
    (National Sceince Council:Colombo, 1989) Wijeyaratna, W.M.M.S.U.; Samarajeewa, U.; Thattil, R.O.
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    Impact of production consumption, exports and stocks on the price of natural rubber in Sri Lanka
    (Rubber Research Institute. Agalawatta, 1997) Wijesuriya, B.W.; Thattil, R.O.
    The relationship between price of Natural Rubber (NR)with factors such as:production,consumption,exports and stocks are important in identifying the nature of competetion and therefore reveals the market structure for NR.This paper examines these relationships and also the seasonal variation of these factors,using time series statistical tools,viz Cross Correlation Functions (CCF)and seasonal indices. There is a marked seasonality in production with values below average during April to October (2nd and 3rd quarters).Prices tend to fall when the production rises.A similar phenomenon was observed between price and exports.However,the effect of production or exports on price is mild. A similar pattern of seasonal variation was observed for consumption and stocks of NR.More rubber is consumed during the latter part of the year.An accumulation of stocks was observed towards the end of the year.However,price of NR was not significantly related to consumption or stocks.This is mainly due to the fact that only a few buyers influence prices through their purchase and by adjustments of stocks as in an oligopolistic market.
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    Evaluation of performance of public schools:an application of GIS in education surveys
    (Postgraduate Institute of Agriculture, University of Peradeniya:Peradeniya, 2001) Satharasinghe, A.J.; Thattil, R.O.; Samita, S.; De Silva, R.P.
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    Methods of data analysis for intercropping systems under rubber
    (Rubber Research Institute. Agalawatta, 2001) Wijesuriya, W.; Thattil, R.O.
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    Evaluation of ISO recommendation on analysis of precision experiments for statistical quality control
    (Rubber Research Institute. Agalawatta, 1999) Wijesuriya, W.; Thattil, R.O.
    Application of appropriate statistical methods is an important task in any quality control process as various statistical approaches such as;sampling,experimentationand process control are involved in quality control lprocesses.This has become an essential practice in many areas since the introduction of ISO quality assurance scheme .This article focuses on precision experiments where several laboratories are compared for a standard measurement method.The whole plrocess of analysis and interpretation suggested by ISO is evauated and documented in a sequential order.In addition to the ISO recommendation,additional graphical methods are suggested for better judgement .The statisticans role as a member of the panel is also lpresented at each step of the quality control process.