530 research outputs found
Rare semileptonic decay of meson In QCD
The rare semileptonic decay
is analyzed, by using the three-point QCD sum rules. Taking into account the
two-gluon condensate contributions, the transition form factors related to this
decay are calculated and are used to determine the total decay width and
branching fraction. Our findings may be approved by future experiments.Comment: 15,
Environmental impacts of irrigated and rain-fed barley production in Iran using life cycle assessment (LCA)
Current intensive grain crops production is often associated with environmental burdens. However, very few studies deal with the environmental performance of both current and alternative systems of barley production. This study was undertaken to evaluate energy consumption and environmental impacts of irrigated and rain-fed barley production. Additionally, three alternative scenarios were examined for irrigated barley fields including conservation tillage and biomass utilization policies. The findings showed that around 25 GJ/ha energy is needed in order to produce 2300 kg/ha irrigated barley and 13 GJ/ha for 1100 kg/ha rain-fed barley. Life cycle assessment (LCA) results indicated that irrigated farms had more environmental impacts than rain-fed farms. Electricity generation and consumption had the highest effect on the abiotic depletion potential, human toxicity potential, freshwater and marine aquatic ecotoxicity potential. However, alternative scenarios revealed that using soil conservation tillage systems and biomass consumption vs. gas for electricity generation at power plants can significantly mitigate environmental impacts of irrigated barley production similar to the rain-fed conditions while higher yield is obtained
Blockchain for secured IoT and D2D applications over 5G cellular networks : a thesis by publications presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Computer and Electronics Engineering, Massey University, Albany, New Zealand
Author's Declaration: "In accordance with Sensors, SpringerOpen, and IEEE’s copyright policy, this thesis contains the accepted and published version of each manuscript as the final version. Consequently, the content is identical to the published versions."The Internet of things (IoT) is in continuous development with ever-growing popularity. It brings significant benefits through enabling humans and the physical world to interact using various technologies from small sensors to cloud computing. IoT devices and networks are appealing targets of various cyber attacks and can be hampered by malicious intervening attackers if the IoT is not appropriately protected. However, IoT security and privacy remain a major challenge due to characteristics of the IoT, such as heterogeneity, scalability, nature of the data, and operation in open environments. Moreover, many existing cloud-based solutions for IoT security rely on central remote servers over vulnerable Internet connections. The decentralized and distributed nature of blockchain technology has attracted significant attention as a suitable solution to tackle the security and privacy concerns of the IoT and device-to-device (D2D) communication. This thesis explores the possible adoption of blockchain technology to address the security and privacy challenges of the IoT under the 5G cellular system.
This thesis makes four novel contributions. First, a Multi-layer Blockchain Security (MBS) model is proposed to protect IoT networks while simplifying the implementation of blockchain technology. The concept of clustering is utilized to facilitate multi-layer architecture deployment and increase scalability. The K-unknown clusters are formed within the IoT network by applying a hybrid Evolutionary Computation Algorithm using Simulated Annealing (SA) and Genetic Algorithms (GA) to structure the overlay nodes. The open-source Hyperledger Fabric (HLF) Blockchain platform is deployed for the proposed model development. Base stations adopt a global blockchain approach to communicate with each other securely. The quantitative arguments demonstrate that the proposed clustering algorithm performs well when compared to the earlier reported methods. The proposed lightweight blockchain model is also better suited to balance network latency and throughput compared to a traditional global blockchain.
Next, a model is proposed to integrate IoT systems and blockchain by implementing the permissioned blockchain Hyperledger Fabric. The security of the edge computing devices is provided by employing a local authentication process. A lightweight mutual authentication and authorization solution is proposed to ensure the security of tiny IoT devices within the ecosystem. In addition, the proposed model provides traceability for the data generated by the IoT devices. The performance of the proposed model is validated with practical implementation by measuring performance metrics such as transaction throughput and latency, resource consumption, and network use. The results indicate that the proposed platform with the HLF implementation is promising for the security of resource-constrained IoT devices and is scalable for deployment in various IoT scenarios.
Despite the increasing development of blockchain platforms, there is still no comprehensive method for adopting blockchain technology on IoT systems due to the blockchain's limited capability to process substantial transaction requests from a massive number of IoT devices. The Fabric comprises various components such as smart contracts, peers, endorsers, validators, committers, and Orderers. A comprehensive empirical model is proposed that measures HLF's performance and identifies potential performance bottlenecks to better meet blockchain-based IoT applications' requirements. The implementation of HLF on distributed large-scale IoT systems is proposed. The performance of the HLF is evaluated in terms of throughput, latency, network sizes, scalability, and the number of peers serviceable by the platform. The experimental results demonstrate that the proposed framework can provide a detailed and real-time performance evaluation of blockchain systems for large-scale IoT applications.
The diversity and the sheer increase in the number of connected IoT devices have brought significant concerns about storing and protecting the large IoT data volume. Dependencies of the centralized server solution impose significant trust issues and make it vulnerable to security risks. A layer-based distributed data storage design and implementation of a blockchain-enabled large-scale IoT system is proposed to mitigate these challenges by using the HLF platform for distributed ledger solutions. The need for a centralized server and third-party auditor is eliminated by leveraging HLF peers who perform transaction verification and records audits in a big data system with the help of blockchain technology. The HLF blockchain facilitates storing the lightweight verification tags on the blockchain ledger. In contrast, the actual metadata is stored in the off-chain big data system to reduce the communication overheads and enhance data integrity. Finally, experiments are conducted to evaluate the performance of the proposed scheme in terms of throughput, latency, communication, and computation costs. The results indicate the feasibility of the proposed solution to retrieve and store the provenance of large-scale IoT data within the big data ecosystem using the HLF blockchain
Sustainable and efficient energy consumption of corn production in Southwest Iran: combination of multi-fuzzy and DEA modeling
A motion cueing algorithm based on model predictive control using terminal conditions in urban driving scenario
Calculating the Cost of Co2e Emitted to Generate the Required Electricity: Case Study of Lecture Rooms in the Faculty of Engineering- Universiti Putra Malaysia.
Malaysia is endowed with abundant supplies of non-renewable energy resources, especially oil and gas. However, its current oil and gas reserves are expected to be depleted within the next few years. If new oil fields are not found, Malaysia will have its oil depleted around 2030.Malaysia has actively participated and involved in key conventions regarding environment and sustainable development, such as Montreal Protocol and Kyoto Protocol. University Putra Malaysia (UPM) as one of the largest universities in Malaysia should try to make its energy consumption as efficient as possible and Faculty of Engineering may be the pioneer in this regard. As the result of this study we can see that only for generating the required electricity for the eight lecture rooms at faculty of engineering about RM 45 per day is the cost of Co2e emissions. In this study authors will calculate the cost of Co2e Emitted to Generate the Required Electricity for the Lecture Rooms in the Faculty of Engineering of Universiti Putra Malaysia
Sustainability of wheat production in Southwest Iran : A fuzzy-GIS based evaluation by ANFIS
Funding Information: The financial support provided by Jahrom University, Iran, is gratefully acknowledged. Acknowledgements Publisher Copyright: © 2017 The Author(s). This open access article is distributed under a Creative Commons Attribution (CC-BY) 4.0 license.Peer reviewedPublisher PD
Improving purchasing performance by implementation of QMS process management approach in a manufacturing company
Process oriented approach in quality management system has been introduced with ISO9001:2000. The international standard promotes the adoption of a process approach when developing, implementing and improving the effectiveness of a QMS to enhance customer satisfaction by meeting customer requirement. The advantage of process approach is to link all parties in scope of business of the organization from suppliers, internal departments of organization to gather to make B2B communication and integration. In this paper, the process approach is defined based on QMS requirement. Supply department was proposed for implementation of process. Purchasing process was designed as a linkage between supplier and internal company departments. Performance indicators were developed and measured accordingly. It shows that process management can improve delivery capability, quality and monitor price of supplied parts by suppliers
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