We consider a memoryless single station service system with servers S = {m1, . . . , mK}, and with job types C = {a, b, . . .}. Service is skill based, so that server mi can serve a subset of job types C(mi). Waiting jobs are served on a first come first served basis, while arriving jobs that find several idle servers are assigned to a feasible server randomly. We show that there exist assignme...

Global System for Mobile Communications (GSM) supports full-rate and half-rate calls. In this paper, we propose analytical and simulation models to study the performance of four channel assignment schemes for GSM half-rate and full-rate traac. Our study indicates that among the four schemes, the repacking scheme has the best performance for mixing half-rate and full-rate traac. We also observe ...

in this paper, a new approach was presented for bus network design which took the effects of three out of four stages of the bus planning process into account. the presented model consisted of three majors steps 1- network design procedure (ndp), 2- frequency determination and assignment procedure (fdap), and 3- network evaluation procedure (nep). genetic algorithm (ga) was utilized to solve th...

With the characteristic of spatial diversity and low cost, cooperative system is a tendency for the future communications. In the wireless communication system, there exist degradation factors such as signal fading, multipath transmission, signal inferences, bandwidth limitation and so on. In addition to these degradation factors, the wireless transmission is not a secure environment. The infor...

Recently, there is a growing interest in the industry to replace traditional straight assembly lines with U-shaped lines for more flexibility and higher productivity. Due to mathematical and computational complexity, assembly line balancing problems are known to be NP hard in nature. Therefore, many meta-heuristics have been proposed to find optimal solution for these problems. This paper prese...

In this paper we consider WDM networks with a tunable transmitter and a fixed-wavelength receiver at each station (similar results hold when the transmitter is fixed and the receiver is tunable). Traditionally, each station is required to be able to access all wavelength channels used in the network. Such requirement limits the number of wavelengths that can be exploited in a WDM network up to ...

Decentralized magnetic indoor localization is a sophisticated method for processing sampled magnetic data directly on a mobile station (MS), thereby decreasing or even avoiding the need for communication with the base station. In contrast to central-oriented positioning systems, which transmit raw data to a base station, decentralized indoor localization pushes application-level knowledge into ...

Considering a multihop cellular system with one relay per sector, an effective modeling for the joint base-station/relay assignment, rate allocation, and routing scheme is proposed and formulated under a single problem for the downlink. This problem is then formulated as a multidimensional multichoice knapsack problem (MMKP) to maximize the total achieved throughput in the network. The well-kno...

The hypercube is a widely used interconnection topology as it presents a lot of attractive properties. Recently, the hypercube has been proposed as a virtual topology for TWDM multihop lightwave networks based on optical passive star couplers. However, in most of previous works, each station in the network has only one fixed or tunable transmitter and one fixed or tunable receiver. The tunable ...