in this paper, a model based on gmdh type neural network, is used to predict gas price in the spot market while using oil spot market price, gas spot market price, gas future market price, oil future market price and average temperature of the weather. the results suggest that gmdh neural network model, according to the root mean squared error (rmse) and direction statistics (dstat) statistics ...

social network analysis used to study the relationship between stakeholders and actors in natural resource management has become a scientific approach. the purpose of this study was analysis of information exchange network among organizations engage in the sustainable management of natural resources. results of social network analysis revealed that there is weak relationship among organizations...

Abstract: In this research, at first, the natural frequencies of a cracked beam are obtained analytically, then, location and depth of a crack in beam is identified by neural network method. The research is applied on a beam with an open crack for three different boundary conditions. For this purpose, at first, the natural frequencies of the cracked beam are obtained analytically, to get the ex...

social learning and knowledge generation are two key factors to achieve successful natural resources co-management. social learning can be beneficial by broadcasting and transmitting experiences and problem solving ideas in a group of people. social learning networks can transmit knowledge and experiences from one node to another in the network. social learning can produce a suitable learning a...

An Ant Colony Optimization (ACO) algorithm is proposed for optimal tree-structured natural gas distribution network. Design of pipelines, facilities, and equipment systems are necessary tasks to configure an optimal natural gas network. A mixed integer programming model is formulated to minimize the total cost in the network. The aim is to optimize pipe diameter sizes so that the location-alloc...

the main aim of this paper is to find the optimum shape of arch dams subjected to multiple natural frequency constraints by using an efficient methodology. the optimization is carried out by charged system search algorithm and its enhanced version. computing the natural frequencies by finite element analysis (fea) during the optimization process is time consuming. in order to reduce the computa...

urban landscape structural analysis; focused on the remnant patch mosaic network as the component with closest interdependency with air and water related processes was undertaken to find and propose environmental planning suggestions.assessments demonstrate that remnant patch mosaic network structure of tehran is still restorable. with appropriate corrective measures based on the natural lay ou...