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1.
The development of digital transformation in the construction industry has led to the increasing adoption of smart contracts. As programmable applications to automatically write, verify, and enforce transaction conditions, smart contracts can be used in different areas mainly to improve automation level, information security, and built digital environment enhancement. However, the smart contract is commonly mentioned as a blockchain appendage, while its unique connotation and value in the construction industry have not been recognized. Therefore, this study carries out a systematic review based on 81 research articles published from 2014 to 2021 on smart contract applications in construction to explore and highlight their potentials under domain-specific requirements. Results are analyzed according to research type categorization and domain codification. Eight research domains are identified, where the three most highly explored domains are contract and payment, supply chain and logistics, and information management. The integration of smart contracts with other innovative concepts and advanced technologies is analyzed. The applicability, benefits, and challenges of smart contract applications regarding different research domains are discussed. 相似文献
2.
Pengcheng Li Xiuxia Xu Junjie Zhao Pragati Awasthi Xusheng Qiao Jincheng Du Xianping Fan Guodong Qian 《中国稀土学报(英文版)》2022,40(2):169-192
Significant developments have been made in the past few decades for lanthanide(Ln)ions doped fluorosilicate glass-ceramics(Flusi-GCs).As novel generation of luminescence materials with a wide range of applications,Flusi-GCs as a single host combine the advantages of glass and ceramics/crystals as well as fluorides and silicates.In this review,the chemical design principles and experimental procedures of Flusi-GCs are summarized in detail.Flusi-GCs are categorized as those containing PbxCd1-xF2,RF3(R=Y,La,Gd),MF2(M=Ca,Sr,Ba),xMF2-yRF3(R=Y,La-Lu),mAF-nRF3(A=Li,Na,K),KTF3(T=Zn,Mn)and K2 SiF6 nanocrystals(NCs).Theoretical breakthroughs mainly by molecular dynamic(MD)simulation have been recapitulated as efficient routes for composition-design,nano-crystallization-prediction,and performance-optimization of Flusi-GCs containing target fluoride NCs.Essential research progresses pertaining photonic applications have been made in random lasers,communication amplifiers,optical fibers,spectral converters,white light-emitting-diodes(WLEDs),and thermal sensors.In the end,we propose three future research directions for Flusi-GCs. 相似文献
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大数据场景下,远程云服务器通常被部署用于数据处理与价值挖掘,但在面对时延敏感型或需要动态频繁交互的业务时,该种处理模式显得力不从心.作为对云计算模式的补充,雾计算因其可有效降低任务处理时延、能耗与带宽消耗而备受关注;同时,面向雾计算的计算迁移机制因其能有效缓解节点的处理负担并改善用户体验而成为领域研究焦点.在雾计算模式下,为了更好地满足计算密集型任务对时延与能耗的要求,基于区块链赋能物联网场景,本文提出了一种联合资源分配与控制的智能计算迁移方案.具体地,规划了一个在时延、能耗与资源约束下的最小化所有任务完成总成本的优化问题,其总成本构成综合考量了时延、能耗和挖掘成本,通过对通信、计算资源与迁移决策的联合优化,实现总成本的最小化.为完成任务迁移,终端以矿工的身份向雾节点挖掘(租借)计算资源,所提出的基于区块链技术的激励机制可充分调动终端和雾节点参与计算迁移的积极性并保障交易过程的安全性,设计的奖励分配规则可保证成功挖掘资源终端收获奖励的公平性.为解决上述规划的优化问题(即混合整数非线性规划问题),提出了一个联合通信、计算与控制的智能计算迁移算法,该算法融合深度确定性策略梯度算法思想,设计了基于反梯度更新的双“行动者-评论家”神经网络结构,使训练过程更加稳定并易于收敛;同时,通过对连读动作输出进行概率离散化运算,使其更加适用于混合整数非线性规划问题的求解.最后,仿真结果表明本文方案能以较快的速度收敛,且与其他三种基准方案相比,本文方案的总成本最低,例如,与其中性能最好的基于深度Q学习网络的计算迁移方案相比,总成本平均可降低15.2%. 相似文献
4.
Ali Alkhalifah 《计算机系统科学与工程》2022,42(2):639-658
Owing to constant changes in user needs, new technologies have been introduced to keep pace by building sustainable applications. Researchers and practitioners are keen to understand the factors that create an attractive user interface. Although the use of cross-platform applications and services is increasing, limited research has examined and evaluated cross-platforms for developing mobile applications for different operating systems. This study evaluates cross-platform features, identifying the main factors that help to create an attractive user adaptation when building sustainable applications for both Android and iOS. Flutter and React Native were selected so end-users could test their features using the cross-platform usability assessment model. Usability, satisfaction, and navigation were tested to measure the cross-platform adaptation and end-user experience. The data were analyzed using hybrid structural equation modeling (SEM) and artificial neural network (ANN) approaches. The study results show that usability and navigation both have a positive effect on adaptation on Flutter and React Native, while satisfaction only has an effect on Flutter. The navigation variable was also the most significant predictor of adaptation for both models. This study has several implications and makes contributions to the research field, to developers, and to end-users. 相似文献
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转炉残极加料机是贵冶转炉重要辅助设备之一。本文分析了贵溪冶炼厂熔炼车间转炉残极加料机运行过程存在的问题。从设备管理角度出发,分析故障原因并提出改进措施。同时改变现有残极加入的方式,顺应时代趋势,实现自动化、岗位无人化操作并在一定程度上得到应用。 相似文献
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介绍了国内无底层取向电工钢生产技术水平、产量和用途,简述了无底层取向电工钢作为取向电工钢超/极薄带母料及应用于制作大型发电机组铁心、风电等电机铁心和变压器铁心等的情况。 相似文献