1. introduction as strongly accepted among climatologists, climate change is a result of human activities. there is disagreement about how to define climate change, because of tremendous difference of climate changes in scale, intensity and occurrence time in various regions. recently there have been several observation analyses involving daily and extreme daily temperature trend and variabilit...

the aim of this paper is detection of exist of significance climatic trend in west-half of iran. it’s used monthly data of 16 climatic variables on 12 selected synoptic stations in period of 50 years statistic(1951-2000). the variables divided to two temperature and humid groups. the analysis methodology of the study is based on multivariable statistical analysis and box- jenkins forecasting mo...

A number of objective functions in clustering problems can be described with submodular functions. In this paper, we introduce the minimum average cost criterion, and show that the theory of intersecting submodular functions can be used for clustering with submodular objective functions. The proposed algorithm does not require the number of clusters in advance, and it will be determined by the ...

precipitation is one of important parameters of climatology and atmospheric science that have more importance in human life. recently, extensive flood and drought entered many damage to most parts of the world. precipitation forecasting and alerts management role is responsible for these problems. today, artificial neural networks are one of developed method that applied for estimate and predic...

Some of the following problems look similar to the MAD Triangulation problem, but we have not found any deep connections: •Minimum Average Distance Spanning Subgraph in a budgeted version [2] was studied in the context of network design (minimizing average routing time). The problem is NP-complete even with unit weights. •Minimum Average Distance Spanning Tree [1]. NP-completeness is implied by...

In this paper, we have examined the effect of climate variables on the yield average and variability of major grain crops (rice, maize, and wheat) in Iran from 1983 to 2014. For this purpose, we made use of the Just and Pope Production Function crop yields panel data. The results revealed that the influences of climate variables were different in the crops. The time trend positively influenced ...