INTRODUCTION Sci-Hub is a useful web portal for people working in science as it provides access to millions of free scientific articles. Satisfaction and usage should be explored in the Latino student population. The objective of this study was to evaluate the use, knowledge, and perception of the scientific contribution of Sci-Hub in medical students from Latin America. METHODOLOGY A multice...

the hub location decision is a long term investment and any changes in it take considerable time and money. in real situations, some parameters are uncertain hence, deterministic models cannot be more efficient. the ability of two-stage stochastic programming is to make a long-term decision by considering effects of it in short term decisions simultaneously. in the two-stage stochastic programm...

in this paper we present the problem of designing a three level hub center network. in our network, the top level consists of a complete network where a direct link is between all central hubs.  the second and third levels consist of star networks that connect the hubs to central hubs and the demand nodes to hubs and thus to central hubs, respectively. we model this problem in an incomplete net...

The present paper deals with a variant of hub location problems (HLP): the uncapacitated single allocation p-Hub median problem (USApHMP). This consists to jointly locate facilities and allocate demand nodes these selected facilities. objective function is minimize routing demands between any origin destination pair nodes. known be NP-hard. Based on artificial immune systems (AIS) framework, th...

In this paper we consider a capacitated single allocation p-hub median problem (CSApHMP) which is to determine the location of p hubs, the allocation of non-hub nodes to hubs in the logistics network. This problem is formulated as an integer programming model with the objective of minimizing the sum of total transportation cost and fixed cost of the selected p hubs. Since the CSApHMP is NP-hard...

in this paper smart operation of micro energy hub is presented. energy hub system consists of certain energy hubs and interconnectors that are coordinated by energy hub system operator. an energy hub contains several converters and storages to serve demanded services in most efficient manner from available energy carriers. in this paper, the flexibility of energy delivery point is enhanced u...

This paper proposes a new lower bounding procedure for the Uncapacitated Single Allocation p-Hub Median Problem based on Lagrangean relaxation. For solving the resulting Lagrangean subproblem, the given problem structure is exploited: it can be decomposed into smaller subproblems that can be solved efficiently by combinatorial algorithms. Our computational experiments for some benchmark instanc...

The goals of hub location problems are finding the location of hub facilities and determining the allocation of non-hub nodes to these located hubs. In this work, we discuss the multi-modal single allocation capacitated p-hub covering problem over fully interconnected hub networks. Therefore, we provide a formulation to this end. The purpose of our model is to find the location of hubs and the ...