scalability analysis
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Supply chain management (SCM) is essential for a company’s faster, efficient, and effective product life cycle. However, the current SCM systems are insufficient to provide product legitimacy, transaction privacy, and security. Therefore, this research proposes a secure SCM system for the authenticity of the products based on the Internet of Things (IoT) and blockchain technology. The IoT-enabled Quick Response (QR) scanner and the blockchain-integrated distributed system will allow all the SCM stakeholders to begin secure and private transactions for their products or services. Resulting, the consumer will receive an authentic and genuine product from the original producer. A lightweight asymmetric key encryption technique, i.e., elliptic curve cryptography (ECC) and Hyperledger Fabric-based blockchain technology with on-chain smart contracts are applied for distributed IoT devices to make the authentication process faster and lighter. Each SCM stakeholder is registered by the service provider and receives corresponding public and private keys, which will be used for the authentication process of the participants and IoT devices. The authenticated QR scanner records all transactions on the blockchain. Consequently, there will be no human intervention for the SCM transactions. The security and scalability analysis demonstrates that the proposed system is more secure and robust than other state-of-the-art techniques.

AbstractThis paper presents an investigation into the effect of faults on the scalability resilience of cloud-based software services. The study introduces an experimental framework using the Application-Level Fault Injection (ALFI) to investigate how the faults at the application level affect the scalability resilience and behaviour of cloud-based software services. Previous studies on scalability analysis of cloud-based software services provide a baseline of the scalability behaviour of such services, allowing to conduct in-depth scalability investigation of these services. Experimental analysis on the EC2 cloud using a real-world cloud-based software service is used to demonstrate the framework, considering delay latency of software faults with two varied settings and two demand scenarios. The experimental approach is explained in detail. Here we simulate delay latency injection with two different times, 800 and 1600 ms, and compare the results with the baseline data. The results show that the proposed approach allows a fair assessment of the fault scenario’s impact on the cloud software service’s scalability resilience. We explain the use of the methodology to determine the impact of injected faults on the scalability behaviour and resilience of cloud-based software services.

Abstract The Operating Room Scheduling (ORS) problem is the task of assigning patients to operating rooms (ORs), taking into account different specialties, lengths, and priority scores of each planned surgery, OR session durations, and the availability of beds for the entire length of stay (LOS) both in the Intensive Care Unit (ICU) and in the wards. A proper solution to the ORS problem is of primary importance for the healthcare service quality and the satisfaction of patients in hospital environments. In this paper we first present a solution to the problem based on Answer Set Programming (ASP). The solution is tested on benchmarks with realistic sizes and parameters, on three scenarios for the target length on 5-day scheduling, common in small–medium-sized hospitals, and results show that ASP is a suitable solving methodology for the ORS problem in such setting. Then, we also performed a scalability analysis on the schedule length up to 15 days, which still shows the suitability of our solution also on longer plan horizons. Moreover, we also present an ASP solution for the rescheduling problem, that is, when the offline schedule cannot be completed for some reason. Finally, we introduce a web framework for managing ORS problems via ASP that allows a user to insert the main parameters of the problem, solve a specific instance, and show results graphically in real time.

A reliable log system is a prerequisite for many applications. Financial systems need to have transactions logged in a precise manner, medical systems rely on having trusted medical records and security logs record system access requests in order to trace malicious attempts. Keeping multiple copies helps to achieve availability and reliability against such hackers. Unfortunately, maintaining redundant copies in a distributed manner in a byzantine setting has always been a challenging task, however it has recently become simpler given advances in blockchain technologies. In this work, we present a tamper-resistant log system through the use of a blockchain. We leverage the immutable write action and distributed storage provided by the blockchain as a basis to develop a secure log system, but we also add a privacy preserving layer that is essential for many applications. We detail the security and privacy aspects of our solution, as well as how they relate to performance needs in relevant settings. Finally, we implement our system over Hyperledger Fabric and demonstrate the system’s value for several use cases. In addition, we provide a scalability analysis for applying our solution in a large-scale system.

AbstractFull Adder (FA) circuits are integral components in the design of Arithmetic Logic Units (ALUs) of modern computing systems. Recently, there have been massive research interests in this area due to the growing need for low-power and high-performance computing systems. Researchers have proposed a variety of FA cells with diverse design techniques, each having its pros and cons. As a result, a systematic method for performance comparison of FA cells using a common simulation platform has become necessary. In this work, we present an extensive study of FA cells. We have compared the performance of thirty-three (33) existing 1-bit FA cells. The drive powers of these FA cells have been compared by applying a variety of load conditions. In addition, the 1-bit FA cells have been extended to 32-bit structures to test their scalability and to investigate their performance in wide-word structures. We have determined that twenty-one (21) of the thirty-three (33) FA cells cannot operate in a 32-bit structure, even though some of them exhibit excellent performance as a 1-bit cell. The main finding of this research is that the single-bit performance parameters of FA cells should not be considered as the main basis for performance comparison. Any FA cell should be analyzed in a multi-bit structure to determine its practical effectiveness.