The shopping experience in Omni-CHANNEL distributions is influenced by the physical environment of the buyer, delivery time, and the cost of production to distribution of the goods which have a significant impact on customer loyalty and customer satisfaction. This study presents a system dynamics approach to identify the variables affecting the three aspects of customer satisfaction, cost, and delivery time, as well as the relationships among these variables in omni-CHANNEL distribution. By reviewing previous studies and expert opinions identifying important variables, followed by generating different scenarios in the Vensim software, the optimal values of the important variables are estimated. It is observed that by approaching the values of the fourth scenario – increase in the amount of market competitiveness indices, customer referral rate, marketing costs, technology etc. and decrease in the maintenance costs – the highest customer satisfaction and the lowest cost and delivery time can be achieved.

In this paper the secrecy problem in the cognitive state-dependent interference CHANNEL is considered. In this scenario we have a primary and a cognitive transmitter-receiver pairs. The cognitive transmitter has the message of the primary sender as side information. In addition, the state of the CHANNEL is known at the cognitive encoder. Hence, the cognitive encoder uses this side information to cooperate with the primary transmitter. The message of the cognitive encoder must be secret at the primary receiver, i.e., the primary receiver act as an eavesdropper for the cognitive transmitter. An achievable rate region and an outer bound on the rate region in this CHANNEL are derived. The results are extended to the previous works as special cases.

In this paper optimization of frequency offset estimation technique based on CHANNEL estimation, which is desirable for frequency selective CHANNELs and hasfast convergence speed, for using in HF CHANNEL is addressed. Because of time variations coherence time in HF CHANNEL is short, which leads to a severe degradation in the performance of above technique in this CHANNEL. An optimization of said technique is proposed in which after removing coarse frequency offset estimation and knowing residual frequency offset range, incorrect estimations can be removed and others can be averaged to give final correct estimate. Simulation is conducted underCHANNEL parameters with respect to MIL-STD-188-110B. the results show that proposed optimization result in improved performance of frequency offset estimation technique based on CHANNEL estimation.

We study an entangled two-mode coherent state within the framework of 2×2-dimensional Hilbert space. We investigate the problem of quantum teleportation of a superposition coherent state via an entangled coherent CHANNEL. By three different measures with the titles ``minimum assured fidelity (MASF)” , ``average teleportation fidelity” and ``optimal fidelity (f)” we study the quality of this kind of teleportation. Decoherence properties of the entangled coherent state due to CHANNEL losses are analysed. For a symmetric noise CHANNEL, the degradation of optimal fidelity and degree of entanglement are calculated. Also by two different measures with the titles ``concurrence” and ``entanglement of formation” we study the amount of entanglement of a decohered quantum CHANNEL and discuss its details. We demonstrate that entanglement of the decohered entangled coherent state is reduced but not throughly lost. Finally we find that the optimal fidelity of the decohered entangled coherent state is more than the classical limit and the decohered entangled coherent state may be useful for quantum teleportation.

The progress of the technology in the recent decades has caused the video transmission by communication CHANNELs to meet high demands. Therefore, many methods have been proposed to improve the quality of the video under CHANNEL errors. The aim of this paper is to increase the Peak Signal to the Noise Ratio (PSNR) for video reconstructed by the receiver. This is achieved by increasing CHANNEL encoder rate but in constant transmission rate. In the proposed method the video frames’ parts containing more energy are coded by the local CHANNEL coding inside the source encoder. Then, the resulted data is embedded in the low power frames’ parts. The proposed method is able to increase the CHANNEL coding rates without increasing the amount of the information for any frame. This method provides more robustness for video frames against CHANNEL errors. The proposed method is tested for different source coding rates and several Signals to Noise Ratio (SNRs) for CHANNEL and the obtained results are compared with a new method.

In this paper, the designing of a parallel CHANNEL queuing system is considered in which it is desirable to serve the customers immediately upon their arrival. To design such a service facility, the first and the second moments of the number of customers are obtained in an infinite CHANNEL server under the assumption that the arrival process has a general probability structure and the service times of customers are independent and identically distributed random variables. With the knowledge about the above two moments, one can obtain the approximate number of CHANNELs such that the queue length becomes zero.    

Dropping probability of handoff calls and blocking probability of new calls are two important QoS measures for cellular networks. Since the dropping probability of handoff calls is more important, call admission policies are used to maintain the upper bound of dropping probability of handoff calls. The fractional guard CHANNEL policy (FG) is a general call admission policy and includes most prioritized CHANNEL allocation schemes such as guard CHANNEL (GC), limited fractional guard CHANNEL (LFG), and uniform fractional CHANNEL policy (UFC) policies. Since the input traffic is not a stationary process and its parameters are unknown a priori, the optimal value of UFC parameter is not known in advance and possibly varies as traffic conditions change. In this paper, we propose two adaptive algorithms based on learning automata for finding the optimal value of UFC parameter. To evaluate the proposed algorithms, the computer simulations are conducted. The simulation results show that for some range of input traffic, the performance of the proposed algorithms is close to the performance of the uniform fractional CHANNEL policy which knows the traffic parameters a priori.