Optimization and reduction of costs in management of distribution and transportation of commodity are one of the main goals of many organizations. Using suitable models in supply chain in order to increase efficiency and appropriate location for support centers in logistical networks is highly important for planners and managers. Graph modeling can be used to analyze these problems and many oth...

according to the low efficiency of irrigation and drainage networks and water distribution in iran, simulating water flow and sensitivity structures and networks is considered as a new approach to evaluate the performance hydroelectric projects in the country. in this study, because of reduced water supply and distribution, especially in downstream irrigation and drainage networks varamin to ev...

Several of the most important conservation prioritization approaches select markedly different areas at global and regional scales. They are designed to maximize a certain biodiversity dimension such as coverage of species in the case of hotspots and complementarity, or composite properties of ecosystems in the case of wilderness. Most comparisons between approaches have ignored the multidimens...

Spatial interaction models commonly partition the study area into a number of zones and model the interaction between all zone pairs. For many applications this implies that the computational demands, both in terms for processing time and memory allocation, are quadratic to the number of zones. These practical implications compel modellers to reduce the number of zones and trade accuracy for ef...

extended abstract abstract pressure management is an effective method for water demand management. for evaluation of the effects of pressure changes on leakage level of water networks, the favad equation is usually used. however, in this equation, exponent of pressure parameter (n) needs to be determined. for estimation of n, either some information about the leak opening is necessary or networ...

The tight junction is an intricate seal between adjoining epithelial cells that also separates the apical and basolateral membranes within these cells. A paper in this issue of Cell by Umeda et al. (2006) demonstrates that loss of the ZO scaffolding proteins prevents the formation of tight junctions but surprisingly does not perturb apico-basal polarity.