The form of distribution for the annual minimum flow series | |
| Author | Devkota, Laxmi Prasad |
| Call Number | AIT Thesis no. WA-92-14 |
| Subject(s) | Hydraulics--Mathematical models Distribution (Probability theory) |
| Note | A thesis submitted in partial fulfillment of the requirements for the Degree of Master of Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | Disposal of the sewage , municipal and industrial water supply, irrigation , operation of t he run of the river power plant and maintenance of t he suitable conditions for fish during the dry period requires the information on the low flow. The inference about the probability distribution that is closely followed by the annual minimum flow series is first required to determine t he M-day T-year low flow. Such information is only directly available for sites with long term gaging records. Only a few studies have been made which probability distribution is suitable to fit t he annual minimum flow series. In this study, the records of twenty gaging stations from different parts of Nepal were taken into account to determine the best fitted distribution for one day, seven days and thirty days annual minimum flow data as a required step towards a more comprehensive low flow analysis. Five probability distributions viz. GEV , EV l , LN2 , P3 and LP3 were fit ted to one day, seven days and thirty days minimum flow series of the outlier detected data. Commonly used criteria, such as K-S test , rmse, bias, standard error, efficiency and correlation coefficient were used to distinguish the best fitting distribution among t he considered five distributions. GEV distribution with PWM method of parameter estimation has been found to be t he best fitting distribution for Nepal both for regional and national basis. GEV distribution fitted with PWM remained superior by all criteria whether the river is purely rainfed or both rainfed and snow fed. For P3 and LP3 distributions, MOM method turned out t he preferable method of parameter estimation to MML. |
| Year | 1992 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Water Resources Research Engineering (WA) |
| Chairperson(s) | Hjorth, Peder ;Nophadol In - na |
| Examination Committee(s) | Huynh Ngoc Phien |
| Scholarship Donor(s) | NORAD. |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1992 |