Performance analysis of incremental cooperative relaying system over composite multipath/shadowing fading channels

Since the performance metrics of digital communication systems over composite multipath/lognormal fading channels is intractable,a mixture Gamma (MG) fading model is used to approximate Nakagami-lognormal (NL) fading model.By using MG fading channel model,some exact closed-form expressions of the average error rate and outage probability for incremental cooperative relaying system are obtained,respectively,where per hop is independent and non-identically distributed.Finally,numerical and simulation results are shown to verify the accuracy of the analytical results.These results show that it is helpful to approximate the composite NL distribution by using the MG distribution in the performance analysis of cooperative relaying systems

Optimal Network Defense Decision-making Method Based on Delay-Time Differential Game

Abstract In the process of attack and defense, there will be a period of delay in the implementation of the decision-making and strategy, therefore, the paper is based on the theory of the dynamic and time-delay differential game theory, and puts forward the network security status evolution model, and puts forward the network attack defense delay differential game model, and the design of the method of the optimal defense strategy of the most optimal defense strategy is designed, and the optimal decision is achieved. Finally, the validity of the model and the algorithm is verified by experiment.</jats:p

Solubility of Na 2 O·xAl 2 O 3 in NaF-KF-AlF 3 -based low-temperature electrolyte

Abstract The solubility of Na2O·xAl2O3 in a NaF-KF-AlF3-based low-temperature electrolyte was investigated, and the influence of electrolyte temperature at 750 ℃, CR = 1.3–1.4, CaF2, and LiF on the alumina solubility was studied. The dissolution rate of alumina in the electrolyte was determined by measuring the alumina concentration in the electrolyte at different times with an oxygen analyzer. The results showed that in the NaF-KF-AlF3-based low-temperature electrolyte, the dissolution rate of alumina in Na2O·xAl2O3 was better than that of Al2O3. As the Na2O content in alumina increased, the dissolution rate increased. Similarly, a higher CR of NaF-KF-AlF3 increased the dissolution rate. When the temperature of the molten salt rose (750–850 oC), the dissolution rate of alumina in the electrolyte gradually accelerated. The dissolution rate of alumina in NaF-KF-AlF3 decreased after adding CaF2 and LiF. According to the kinetics analysis, the dissolution rate of alumina followed the zero-order reaction rate law from 0–5 min, which showed that it depended on the amount of alumina absorbed in the electrolyte in the first five minutes.</jats:p

Energy-efficient multi-cell resource allocation in cognitive radio-enabled 5G systems

Abstract In this paper, we propose an energy-efficient resource allocation (RA) algorithm in cognitive radio-enabled 5th generation (5G) systems, where the scenario including one primary system and multiple secondary cells is considered. Because of the high spectrum leakage of traditional orthogonal frequency division multiplexing (OFDM), alternative modulation schemes regarded as the potential air interfaces in 5G are analyzed, e.g., filter bank-based multi-carrier (FBMC), generalized frequency division multiplexing (GFDM), and universal filtered multi-carrier (UFMC). Our objective is to maximize the whole energy efficiency of secondary system defined by the ratio of the capacity to the total power consumption subject to some practical constraints. The general formulation leads to a non-convex mixed-integer nonlinear programming problem with fractional structure, which is challenging to solve due to its intractability and significant complexity. Therefore, we resort to an alternate optimization framework to optimize the variables of subcarrier assignment and power allocation, where successive convex approximation (SCA) is employed so that the general formulation is finally transformed into a solvable convex problem. Numerical results validate the effectiveness of the proposed RA algorithm, and the comparison with some existing RA algorithms is conducted. In addition, the performance of using different 5G candidate waveforms in the energy-efficient RA algorithm is also presented and discussed