the existing works considering the flow-based discount factor in the hub and spoke problems, assume that increasing the amount of flow passing through each edge of network continuously decreases the unit flow transportation cost. although a higher volume of flow allows for using wider links and consequently cheaper transportation, but the unit of flow enjoys more discounts, quite like replacing...

BACKGROUND Monitoring and managing carbon stocks in forested ecosystems requires accurate and repeatable quantification of the spatial distribution of wood volume at landscape to regional scales. Grid-based forest inventory networks have provided valuable records of forest structure and dynamics at individual plot scales, but in isolation they may not represent the carbon dynamics of heterogene...

tobacco is planted extensively in golestan province and high volume of its stem wastes remained without using and it is burned. as a useful purpose of these wastes and to reduce the environmental problems, in this the mechanical properties of polypropylene composites reinforced with tobacco stalk flour were studied. for this purpose, the tobacco stalk flour as the reinforcement, in three levels...

Secure supply of wood remains a challenge partly due to resource conservation efforts that have failed to focus on the sawn wood supply chain as a whole. This study investigated the influence of sawn wood commodity chain profile on its performance. Data were collected from the production and distribution chain of 35 production units selected randomly. Production batches comprising of at least f...

lack of forest management plan and forest road network caused that the traditional tree felling and processing was developed in hyrcanian forest. in this system, trees are felled, limbed and topped motor-manually. felled trees are processed with chainsaws into lumber and/or pulpwood. in order to evaluate this system, lumber processing was studied in two compartments of namkhaneh district in khe...

The possibility of using water insoluble fraction from biomass pyrolysis oil as additive in synthesis of Wood-Plastic novolac has been proved by using Differential Scanning Calorimetry (DSC) and Fourier Transformed Infra Red (FT-IR) spectroscopy. Synthesis of novolac with different concentrations (10, 20 and 30 wt %) of water insoluble fraction were performed. It was found that mechanical p...

the province of bushehr is located in southern area of iran and north of persian gulf. solid waste management in bushehr’s villages was the aim of this research. for the sake of this study, 21 villages scattered all over the province were selected. field studies showed that about 646 grams of residential solid waste per capita is generated in selected villages every day. there are 322 shops i...