Widespread and long-term effects of droughts has caused it to be known as the worst natural disaster that causes water and food deficiency in affected areas. One of the popular indexes in recognizing and monitoring of drought is Standardized Precipitation Index (SPI) that its efficiency has been approved in the world. Trend detection is very important to manage water resources. The Mann-Kendall...

     Knowledge of river discharge and water-quality trend can be useful for planning and management of water resources. Due to the fact that the river base flow is supplied by ground water, considering of base flow for managing environmental demand. The Mann-Kendall's test is one of the approaches which is used for investigating of the trend in time series. In this study, the Mann-Kendall's tes...

the rationale behind the present study is that particular learning strategies produce more effective results when applied together. the present study tried to investigate the efficiency of the semantic-context strategy alone with a technique called, keyword method. to clarify the point, the current study seeked to find answer to the following question: are the keyword and semantic-context metho...

this thesis basically deals with the well-known notion of the bear-invariant of groups, which is the generalization of the schur multiplier of groups. in chapter two, section 2.1, we present an explicit formula for the bear-invariant of a direct product of cyclic groups with respect to nc, c>1. also in section 2.2, we caculate the baer-invatiant of a nilpotent product of cyclic groups wuth resp...

the present study is paid to the evaluation of the welfare program of the unemployment insurance in iran. the main purpose which was the main reason for performing this thesis, was the unemployment insurance plan’s challenges in iran such as financial problems of this plan, prolongation of the credit receipt for some insured people, unemployment slow exiting from the unemployment insurance fund...

     Due to the important role of non-point source pollution in water resources management, in this study time series modeling was applied to forecast water quality parameters and L-THIA model (one type of non-point source pollution models) was applied to estimate water pollutants. The purpose of this study was to compare results of L-THIA model and ARIMA models in Namrood sub-basin located in ...

In this research wavelet coherence measure is implemented for evaluating the relations and effect of rainfall parameters over many years on runoff fluctuations that is for testing proposed linkages between two time series. In this way, monthly Hydro climatological as 3 rainfall stations, one runoff in the outlet of Ardabil plain were used. The results illustrate that 8-12 and 8-16 month modes o...