in this paper, a hierarchical p-hub median problem is considered that all the nodes and arcs on the network have limited capacities. proposed model has three-level where the complete network at the top level consists of the central hubs. the second and third levels consist of hub and demand nodes respectively, which are connected through star networks. also, delivery time restriction is taken i...

We report a case of a 68-year-old female who was a known case of diabetes mellitus and chronic liver disease and presented with complaints of dry cough and other constitutional symptoms since one month. During initial investigations, the patient was found to have peripheral blood eosinophilia. Upon investigating further,the patient was found to have mediastinal lymphadenopathy and fine-needle a...

in this paper, we present a binary-linear optimization model to prevent the spread of an infectious disease in a community. the model is based on the remotion of some connections in a contact network in order to separate infected nodes from the others. by using this model we nd an exact optimal solution and determine not only the minimum number of deleted links but also their exact positions. ...

A p-hub center network design problem is definition of some nodes as hubs and allocation of non-hub nodes to them wherein the maximum travel times between any pair of nodes is minimized. The distinctive feature of this study is proposing a new mathematical formulation for modeling costs in a p-hub center problem. Here, instead of considering costs as a linear function of distance, for the first...

Cooperation is the foundation of many protocols in wireless networks. Without cooperation, the performance of a network significantly decreases. Hence, all nodes in traditional networks are required to cooperate with each other. In this paper, instead of traditional networks, a network of rational and autonomous nodes is considered, which means that each node itself can decide whe...

Convergent product is an assembly shape concept integrating functions and sub-functions to form a final product. To conceptualize the convergent product problem, a web-based network is considered in which a collection of base functions and sub-functions configure the nodes and each arc in the network is considered to be a link between two nodes. The aim is to find an optimal tree of functionali...

background: this study assessed the optimal timing of computed tomography for detection of metastatic disease in locoregional lymph nodes in patients with rectal cancer who have undergone chemoradiotherapy. materials and methods: this observational retrospective study was performed in a single institution. all patients with locally advanced rectal cancer treated with chemoradiotherapy, followed...