Background and Objectives: Blockchain technology as a distributed and tamper-proof data ledger is attracting more and more attention from various fields around the world. Due to the continuously growing of the blockchain in both transaction data and the number of nodes joining the network, Scalability emerges as a challenging issue. Methods: In this survey, the existing Scalability solutions in the blockchain are discussed under five categories including on-chain Scalability, off-chain Scalability, scalable consensus mechanisms, DAG-based Scalability, and horizontal Scalability through sharding. Meanwhile, the novelties they have created on the fundamental layers of the blockchain architecture are investigated.Results: As a result, the advantages and disadvantages of the discussed mechanisms are pointed out, and a comparison between them in terms of different Scalability metrics such as throughput, latency, bandwidth, and storage usage is presented. Therefore, this study provides a comprehensive understanding of the various aspects of blockchain Scalability and the available Scalability solutions. Finally, the research directions and open issues in each category are argued to motivate further improvement efforts for blockchain Scalability in the future.Conclusion: Scalability allows blockchain system to sustain its performance as it grows up. Lack of Scalability has a negative effect on the mass adoption of the blockchain in practical environments. This paper presents a profound analysis of the existing Scalability solutions, the issues and challenges they address, and the ones that are not resolved yet. Consequently, it inspires novel ideas for more scalable and efficient blockchains in the future.

Since their invention, microwaves have found significant use in different fields, including medicines and food processing, as well as sterilization of microorganisms for use in biomedical treatment and research. Various scientific studies have demonstrated microwave application’, s capability as clean technology and a veritable solution for producing a pure and desirable drug candidate in bionutraceuticals processing....

The Scalability of a single gateway LoRa network depends on different parameters such as interference and noise. The scheme of spreading factor allocation can control the interference and noise. This article analyzes the impact of the interference of the concurrent transmission with the same spreading factor (co-SF) and different spreading factor (inter-SF) on the Scalability of the LoRa network. The interference has been modeled as the Poisson point process. The proposed scheme considers the success probabilities and device density (SPD) in each area in determining the width and boundaries of SF areas. The simulation results showed that the proposed SPD scheme had improved 13. 20% over the EIB method in terms of success probability under joint co-SF and inter-SF interference. Also, the coverage probability under the joint impact of cumulative co-SF and inter-SF interference of the SPD and EIB methods is compared in the clean and noisy conditions. The probability of coverage in EIB degrades more than SPD as the Scalability increases. Also, the uplink performance of the proposed SPD scheme has been studied in the absence of any interference under AWGN. SPD has a higher success probability under AWGN than EIB.