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In This Issue In This Issue Ready…set…fuse he fusion of two lipid membranes underlies a huge range of biological phenomena, from infection by enveloped viruses to the secretion of cellular proteins , but a central aspect of membrane fusion has remained mysterious: do the T proteins that mediate fusion act cooperatively or independently? On page 833, Markovic et al. argue that teamwork is the or...

The utilization of low-cost AGVs in the industry is increasing every day, but efficiency these systems low due to lack a central management system. Low-cost AGVs’ main characteristic navigation via magnetic sensors, which they follow tape on ground with low-level automation disadvantages are mainly only one circuit assignment and system intelligence. Therefore, this study, AGV pools were employ...

Given a flight schedule, which is a set of flight segments with specified departure and arrival times, and a set of aircraft:, the fleet assignment problem is to determine which aircraft type should fly each flight segment. The objective is to maximize revenue minus operating costs. In the basic fleet assignment problem considered by Hane et al. (1995) a daily, domestic fleet assignment prohlem...

The fleet size and mix vehicle routing problem (FSMVRP) is a class of combinatorial optimization problem with wide-ranging applications in practice. The purpose of this problem is to manage the routes as well as the type of vehicles. In this paper, we apply a bio-inspired algorithm based on the concept of membrane computing (named BIBMA) to solve FSMVRP. In BIBMA, a cell-like framework and rule...

The changing prices of bunker fuel open the door for substantial cost savings by adjusting the sailing speed of ships. A large ship may be burning up to 100 000 USD of bunker fuel per day, which may constitute more than 75% of its operating costs. Reducing the cruising speed by 20% reduces daily bunker consumption by 50%. However, in order to maintain liner service frequency and capacity, reduc...

In this paper we model and solve the multi-depot fleet size and mix vehicle routing problem (MDFSMVRP). This problem extends the multi-depot vehicle routing problem and the fleet size and mix vehicle routing problem, two logistics problems that have been extensively studied for many decades. This difficult transportation problem combines complex assignment and routing decisions under the object...

The growth of AVL (Automatic Vehicle Location) systems leads to huge amount of data about different parts of bus fleet (buses, stations, passenger, etc.) which is very useful to improve bus fleet efficiency. In addition, by processing fleet and passengers’ historical data it is possible to detect passenger’s behavioral patterns in different parts of the day and to use it in order to improve fle...

The generalized vehicle routing problem (GVRP) involves finding a minimum-length set of vehicle routes passing through a set of clusters, where eachcluster contains a number of vertices, such that the tour includes exactly onevertex from each cluster and satisfies capacity constraints. We consider aversion of the GVRP where the number of vehicles is a decision variable. This...