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© Copyright 2022 The Author(s). In this paper, the impact of the non-linearity of the propagation medium on the extended η - μ fading distribution is studied. In particular, the extended α - η - μ fading model in which the parameter α represents the non-linearity of the propagation environment is presented via providing the exact and asymptotic of the statistical properties, namely, the probability density function (PDF), cumulative distribution function (CDF), and generalized-moment generating function (G-MGF). To this effect, exact closed-form mathematically tractable expressions of the outage probability (OP), average symbol error probability (ASEP), amount of fading (AoF), channel quality estimation index (CQEI) and effective rate (ER) are obtained. The asymptotic behaviour at high average signal-to-noise (SNR) values is also analysed to gain further insights into the influence of the index α on the performance metrics of the wireless communication systems. Moreover, the average channel capacity (ACC) under different adaptive transmission techniques, such as, optimum rate and adaptation (ORA), capacity of the channel with inversion and fixed rate (CIFR), and truncated inversion and fixed rate (TIFR) are derived. The validation of the derived expressions is verified via comparing the numerical results with the Monte-Carlo simulations as well as some previous works for different scenarios.

The infallible imams of Shi'a have a special interest in human values ​​and have repeatedly advised people to adhere to moral virtues. In this study, a collection of ethical narratives of the fifth Imam of Shi'a, Imam Muhammad Bāqir (AS), has been presented, in which verse or verses of the Qur'an have been manifested. These narratives are then analyzed. The verses of the Qur’an have been expressed in the words of Imam Bāqir (AS) in various ways, including: adduce, citation, allusion, adaptation, or expression of instance. This research pursues several goals: First: Understanding how Imam Bāqir (AS) has used the Qur’an in his speech. Second: a detailed understanding of the subject of these narratives and the interpretation of the verses in which they are mentioned; Third: The relationship between the above verses and the narrative text. In the 14 hadiths of Imam Bāqir (AS), about 30 verses of the Qur'an have been manifested which have yielded important results from their analysis. Including: All the Imams in general and Imam Bāqir (AS) in particular, pay great attention to the Quran. And teach people to seek every true idea and belief from the verses of the Qur'an, to question the master and have a scientific debate and controversy, to bring their evidence from the Qur'an as the most important scientific and religious source, and to ignore the word that has no Qur'anic reason, and not to suffice the appearance of Qur'an and pay attention to its hidden meaning. Some of the ethical virtues that Imam Muhammad Bāqir (AS) has explained include: flexibility in accepting the right, believers' dignity, public relations, rationality in public relations, avoiding the vain and futile word, avoiding many questions, avoiding nonsense and slander toward people, avoiding illicit relationships and short-change.

In this research, a mechanochemically activated geopolymer (MG) grout is adopted to activate slag, fly ash, sodium hydroxide, and sodium silicate by dry grinding in a ball mill for 2 h, after which water is the only additive required to initiate the geopolymerization reaction. A conventionally activated geopolymer (CG) grout was also evaluated for comparison purposes. Twenty-four different slag and fly ash mixtures have been prepared at different slag/fly ash ratios (0S100F, 50S50F, 75S25F, and 100S0F) at three different molarities of sodium hydroxide (1.25, 2.5, and 3.75) to assess the behavior of both MG grout and CG grout. A series of tests were examined, such as rheological characteristics, setting time, bleeding, unconfined compressive strength (UCS), ultrasonic pulse velocity (UPV), and scanning electron microscopy (SEM). The experimental results showed that the mechanochemical activation technique reduced the rheological characteristics and fresh properties (setting time and bleeding) of geopolymer grout compared to the conventional activation process. Considering mechanical properties, both UCS and UPV of MG grout were higher than that of CG grout. Furthermore, slag content and sodium hydroxide concentration significantly affected the rheological, fresh, and mechanical properties of all geopolymer grouts regardless of the activation method. Both the rheological characteristics and mechanical properties were increased considerably with the increase in molar concentration and slag content. Whereas the bleeding capacity and setting time dramatically reduced with the increase of molar concentration and slag content.

Data availability statement: The data that support the findings of this study are available from the corresponding author upon reasonable request. Copyright © 2022 The Authors. In this letter, probability density function (PDF) of the sum and maximum of non-identical fluctuating two-ray (FTR) variates are derived in terms of the power and exponential functions. To this effect, novel mathematically tractable expressions of the outage probability (OP) and average bit error probability (ABEP) for both the maximal ratio combining (MRC) and selection combining (SC) diversity receptions are provided. The numerical results are affirmed by the Monte-Carlo simulations for different scenarios.

This paper introduces a smart data packet routing protocol (SMART) based on swarm technology for mobile ad hoc networks. The main challenge facing a routing protocol is to cope with the dynamic environment of mobile ad hoc networks. The problem of finding best route between communication end points in such networks is an NP problem. Swarm algorithm is one of the methods used solve such a problem. However, copping with the dynamic environment will demand the use of a lot of training iterations. We present a new infrastructure where data packets are smart enough to guide themselves through best available route in the network. This approach uses distributed swarm learning approach which will minimize convergence time by using smart data packets. This will decrease the number of control packets in the network as well as it provides continues learning which in turn provides better reaction to changes in the network environment. The learning information is distributed throughout the nodes of the network. This information can be used and updated by successive packets in order to maintain and find better routes. This protocol is a hybrid Ant Colony Optimization (ACO) and river formation dynamics (RFD) swarm algorithms protocol. ACO is used to set up multi-path routes to destination at the initialization, while RFD mainly used as a base algorithm for the routing protocol. RFD offers many advantages toward implementing this approach. The main two reasons of using RFD are the small amount of information that required to be added to the packets (12bytes in our approach) and the main idea of the RFD algorithm which is based on one kind of agent called drop that moves from source to destination only. This will eliminate the need of feedback packets to update the network and offers a suitable solution to change data packet into smart packets. Simulation results shows improvement in the throughput and reduction in end to end delay and jitter compared to AODV and AntHocNet protocols.

A theory to allocate a wavelength in the tree networks coordinated arrangement in m-arity networks is proposed. Wavelength required equations to support all-to-all unicasting in the network according to its depth are presented. Three cases are examined: when nodes are only targets, sources or target and source in the same time. The trade-off between wavelength cost and wavelength conversion cost is considered; therefore, concentration is on wavelength allocation without conversion.

The construction of light-trees is one of the principal sub-problems for all-optical multicast technology in wavelength division multiplexing (WDM) networks. In this paper a new algorithm proposed to maximize quality of service by minimizing dispersion on the converted wavelength. Network cost is significantly reduced by decreasing number of wavelengths and Number of wavelength converters utilized to produce multicast services. The simulation results show that the proposed algorithms have a better performance when compared to existing optimal algorithms.

The accuracy for any spectrum sensing technique in cognitive radio (CR) is affected by the transmission channel parameters such as the signal to noise ratio (SNR). In this paper, a special approach is used to estimate the SNR in the received primary user (PU) signal. This approach is based on using filter bank transform which is called hybrid slantlet transform (HST). This transform decomposes the input PU signal into some sub-bands where some of these sub-bands give the approximate signal power with low noise affects and the others give the approximate noise power. The results for this approach are compared with iterated discrete wavelet transform (DWT) approach. Moreover, these results are shown the superior for HST approach in comparison with iterated DWT approach in reduction of the system complexity computational that it is reduced by 9.75%.

In recent years, Wireless Mesh Networks (WMNs) considered as a practical solution for last-mile broadband wireless internet access. In this mode of wireless ad hoc networks, nodes may play the role of APs or Mesh Routers (MRs) to offer a short way to packets to find their destinations. However, as each node in WMNs has to transmit extra relayed traffic as well as its own; the capacity of such networks is limited by traffic congestion. To alleviate such a problem, Cognitive Radio (CR) technology can be used in which mesh nodes are allowed to use the available frequency bands that are not utilized by any licensed user. However, using this technology will impose several challenges influence the performance of the network. Interference between simultaneous transmissions, fading and environmental noise are the most important challenges that have been discussed widely in the research field. In this paper, we present a cooperative sensing scheme with interference mitigation for WMNs. In particular, we investigate the impact of false-alarm and missed-detection probabilities on the MAC layer performance. We propose a sensing strategy in which the MRs (unlicensed users) can use the available licensed spectrum without causing harmful interference with the licensed users. The simulation results have shown that the proposed scheme can improve the throughput of CR mesh networks.

Dynamic wavelength allocation (DWA) in multicast (MC) switching is investigated in this paper. The aim for this investigation is to maximize the network capacity and minimize the blocking probability in the wavelength division multiplexer network (WDM). By using light splitters (LS) and wavelength converters (WC) in the joint nodes, the WDM network is improved and the wavelength reuse was increased. The result shows that our optimization has increased the network capacity by about 41% compared with previous work.

Dynamic wavelength allocation (DWA) in multicast (MC) switching has been investigated in this paper. The aim for this investigation is to maximize the network capacity and minimize the blocking probability in the wavelength division multiplexing network (WDM). By using light splitters (LS) and wavelength converters (WC) in the joint nodes, the WDM network has been improved. By using our multicast switch the power, delay and desperation have been reduced. The results show that our new algorithm called Highest Number of Destinations (HND) has increased the network capacity compared with previous work.