Attached
The thesis is concerned with a Statistical study of the quality of polypropylene woven sacks, manufactured at Mikechris Industries Limited, Liyanagemulla, Seeduwa, confirming to internationally accepted standard.
The above statistical study has two main aims
(I) to construct quality control charts:
(II) to prepare optimum sampling plans.
In the construction of quality control charts, mean and range charts were employed.
The other aspect of determining the optimum sampling size is established by making use of the Military Standards, and Dodge and Romig L T P D System. Further past information on the behaviour of the process and economy are made use of to develop Bayesian Sampling Schemes. Table giving the critical values and the optimum sample size as applicable to the above product covering appropriate range of values of various parameters have been included in the thesis.