One of the most important issues in area of health and hygiene is location-allocation of organ harvesting centers and transplant centers according to coordination between supply and demand. In this paper, a mathematical model is presented for location-allocation of organ harvesting centers and transplant centers. The proposed model does not only minimize the present value of the total system co...

Dynamic channel resource allocation (DCA) exploiting wideband multiuser diversity can provide data transmission with very high spectral efficiency by scheduling at each dimension (time, frequency, space) the user with the best channel conditions. The main issue arising from this allocation is fairness. Base station or users have to wait until their channel is most favorable to transmit. It is c...

In this thesis, we develop efficient algorithms for the jointly optimal power and chan­ nel resource allocation in different wireless cooperative multiple access systems. In addition, in some cases insight into the structure of the optimal allocation enables the development of modified cooperation schemes with better performance, and efficient algorithms are developed for jointly optimal power ...

The secure communication that multiple OFDMA-based cell-edge mobile stations (MS) can only transmit confidential messages to base station (BS) through an untrusted intermediate relay (UR) is discussed. Specifically, with the destination-based jamming (DBJ) scheme and fixed MS transmission power assumption, our focus is on the joint BS and US power allocation to maximize system sum secrecy rate....

In this paper, we address the problem of QoS (Quality of Service) provisioning for multi-user video streaming over multiple heterogeneous wireless networks based on the distributed, cross-layer design framework. By jointly considering the rate allocation and the Joint Source-Channel Coding (JSCC), our proposal aims at maximizing the QoS provisioning under the given resource constraint. At first...

Secured communications in the presence of eavesdropper node is grave for the successful operations in the wireless relay networks. In the proposed work, choose two hop wireless relay networks to enhance security against the eavesdropper node. This paper considers four node networks, they are one source, and three decode and forward relay, one destination and one eavesdropper node. To transmit t...