the purpose of resent research is to analysis and compares performance evaluation models of selected investment companies in tehran stock exchange market in the field of their portfolio management. the duration of research was between years 2009-2014. statistical society the research is consisting of all active investment companies in in tehran stock exchange market which were 30 companies. vol...

Taking the total volume of import and export trade of Ningbo port in 2004-2011 as the original data, a mathematical model of gray forecasting is established for the total volume of import and export trade of port. The paper predicts the total volume of import and export trade of Ningbo port in 2012-2015 during the 12th Five-Year Plan in accordance with the posterior variance testing. The analys...

As to the established gray model based on the linear time-variant and individual prediction model of ARIMA, this article constructs the combined forecasting model based on the gray model and the time series model by means of relative error weighing. This prediction indicates that both the gray model and ARIMA model exert efficient function on the Torpedo development cost prediction, and the com...

The prediction of regional sulfur dioxide (SO2) emission of thermal power belongs to gray system which has small amounts of samples and little information, so a appropriate forecasting method is essential. Based on thermal power industry SO2 emission data from state department authorities, considering the main factors of China's thermal power industry SO2 predicted emission, we established a co...

In this study, we developed a model of combined streamflow forecasting based on cross entropy to solve the problems of streamflow complexity and random hydrological processes. First, we analyzed the streamflow data obtained from Wudaogou station on the Huifa River, which is the second tributary of the Songhua River, and found that the streamflow was characterized by fluctuations and periodicity...

Accurate prediction of forthcoming oxygen concentration during waterless live fish transportation plays a key role in reducing the abnormal occurrence, increasing the survival rate in delivery operations, and optimizing manufacturing costs. The most effective ambient monitoring techniques that are based on the analysis of historical process data when performing forecasting operations do not ful...

The aim of this work was to develop a system based on modular neural networks and multi-feature texture analysis that will facilitate the automated interpretation of cloud images. This will speed up the interpretation process and provide continuity in the application of satellite imagery for weather forecasting. A series of infrared satellite images from the Geostationary satellite METEOSAT7 we...