in this article, multiple-product pvrp with pickup and delivery that is used widely in goods distribution or other service companies, especially by railways, was introduced. a mathematical formulation was provided for this problem. each product had a set of vehicles which could carry the product and pickup and delivery could simultaneously occur. to solve the problem, two meta-heuristic methods...

In this article, multiple-product PVRP with pickup and delivery that is used widely in goods distribution or other service companies, especially by railways, was introduced. A mathematical formulation was provided for this problem. Each product had a set of vehicles which could carry the product and pickup and delivery could simultaneously occur. To solve the problem, two meta-heuristic methods...

background: dental cobalt base alloys are biocompatible dental materials and have been widely used in dentistry. however, metals are bioinert and may not present bioactivity in human body. bioactivity is the especial ability to interact with human body and make a bonding to soft and hard tissues. the aim of the present research was fabrication and bioactivity evaluation of novel cobalt alloy/ f...

â â â  â â  abstract: â  china and asean have been maintaining a relationship both cooperative and competitive in the textile trade. due to its labor intensive feature and high dependence on foreign trade , the textile trade has received much attention after the 2008 financial crisis. the customs data (classified by the hs code) from year 2006-2009 is employed to research the impact of the cris...