With the increasing popularity of blockchain applications, the security of data sources on the blockchain is gradually receiving attention. Providing reliable data for the blockchain safely and efficiently has become ...With the increasing popularity of blockchain applications, the security of data sources on the blockchain is gradually receiving attention. Providing reliable data for the blockchain safely and efficiently has become a research hotspot, and the security of the oracle responsible for providing reliable data has attracted much attention. The most widely used centralized oracles in blockchain, such as Provable and Town Crier, all rely on a single oracle to obtain data, which suffers from a single point of failure and limits the large-scale development of blockchain. To this end, the distributed oracle scheme is put forward, but the existing distributed oracle schemes such as Chainlink and Augur generally have low execution efficiency and high communication overhead, which leads to their poor applicability. To solve the above problems, this paper proposes a trusted distributed oracle scheme based on a share recovery threshold signature. First, a data verification method of distributed oracles is designed based on threshold signature. By aggregating the signatures of oracles, data from different data sources can be mutually verified, leading to a more efficient data verification and aggregation process. Then, a credibility-based cluster head election algorithm is designed, which reduces the communication overhead by clarifying the function distribution and building a hierarchical structure. Considering the good performance of the BLS threshold signature in large-scale applications, this paper combines it with distributed oracle technology and proposes a BLS threshold signature algorithm that supports share recovery in distributed oracles. The share recovery mechanism enables the proposed scheme to solve the key loss issue, and the setting of the threshold value enables the proposed scheme to complete signature aggregation with only a threshold number of oracles, making the scheme more robust. Finally, experimental results indicate that, by using the threshold signature technology and the cluster head election algorithm, our scheme effectively improves the execution efficiency of oracles and solves the problem of a single point of failure, leading to higher scalability and robustness.展开更多
临床数据交换标准协会(Clinical Data Interchange Standards Consortium,CDISC)创建的数据交换标准能极大地提高临床试验的数据质量和审评效率,被大多数国家所认可和推广。美国FDA和日本药品与医疗器械管理局已经明确规定新药临床试验...临床数据交换标准协会(Clinical Data Interchange Standards Consortium,CDISC)创建的数据交换标准能极大地提高临床试验的数据质量和审评效率,被大多数国家所认可和推广。美国FDA和日本药品与医疗器械管理局已经明确规定新药临床试验必须符合CDISC标准,我国国家药品监督管理局也鼓励使用该标准,但是目前国内临床试验申办方所递交的原始数据和注释病例报告表(annotated case report form,aCRF)绝大多数都不符合CDISC标准,其结构多变、标准化低,在很大程度上影响着新药的审评时间。本文介绍了基于研究数据表格模型(study data tabulation model,SDTM)的aCRF概念和意义,重点阐述了其制作流程和要求,分析了标准化aCRF在国内临床试验中的应用,旨在为推进我国临床试验数据的标准化工作提供借鉴。展开更多
为满足企业经营管理对财务月报准确、严谨、快速和高效报送的需求,设计一种基于SAP BW(SAP Business Warehouse)的财务快月报平台。针对现有报表在出具、调整和报送方面存在的突出问题,阐述该平台的总体框架和设计思路,以及报表展现和...为满足企业经营管理对财务月报准确、严谨、快速和高效报送的需求,设计一种基于SAP BW(SAP Business Warehouse)的财务快月报平台。针对现有报表在出具、调整和报送方面存在的突出问题,阐述该平台的总体框架和设计思路,以及报表展现和报表报送解决方案。实际应用结果表明,基于SAP BW的财务快月报平台既能满足财务报表的准确性要求,又能兼顾报表报送的严谨性和快速性,同时具有良好的可操作性和可推广性,可供同类项目的设计开发参考。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.62102449)the Central Plains Talent Program under Grant No.224200510003.
文摘With the increasing popularity of blockchain applications, the security of data sources on the blockchain is gradually receiving attention. Providing reliable data for the blockchain safely and efficiently has become a research hotspot, and the security of the oracle responsible for providing reliable data has attracted much attention. The most widely used centralized oracles in blockchain, such as Provable and Town Crier, all rely on a single oracle to obtain data, which suffers from a single point of failure and limits the large-scale development of blockchain. To this end, the distributed oracle scheme is put forward, but the existing distributed oracle schemes such as Chainlink and Augur generally have low execution efficiency and high communication overhead, which leads to their poor applicability. To solve the above problems, this paper proposes a trusted distributed oracle scheme based on a share recovery threshold signature. First, a data verification method of distributed oracles is designed based on threshold signature. By aggregating the signatures of oracles, data from different data sources can be mutually verified, leading to a more efficient data verification and aggregation process. Then, a credibility-based cluster head election algorithm is designed, which reduces the communication overhead by clarifying the function distribution and building a hierarchical structure. Considering the good performance of the BLS threshold signature in large-scale applications, this paper combines it with distributed oracle technology and proposes a BLS threshold signature algorithm that supports share recovery in distributed oracles. The share recovery mechanism enables the proposed scheme to solve the key loss issue, and the setting of the threshold value enables the proposed scheme to complete signature aggregation with only a threshold number of oracles, making the scheme more robust. Finally, experimental results indicate that, by using the threshold signature technology and the cluster head election algorithm, our scheme effectively improves the execution efficiency of oracles and solves the problem of a single point of failure, leading to higher scalability and robustness.
文摘临床数据交换标准协会(Clinical Data Interchange Standards Consortium,CDISC)创建的数据交换标准能极大地提高临床试验的数据质量和审评效率,被大多数国家所认可和推广。美国FDA和日本药品与医疗器械管理局已经明确规定新药临床试验必须符合CDISC标准,我国国家药品监督管理局也鼓励使用该标准,但是目前国内临床试验申办方所递交的原始数据和注释病例报告表(annotated case report form,aCRF)绝大多数都不符合CDISC标准,其结构多变、标准化低,在很大程度上影响着新药的审评时间。本文介绍了基于研究数据表格模型(study data tabulation model,SDTM)的aCRF概念和意义,重点阐述了其制作流程和要求,分析了标准化aCRF在国内临床试验中的应用,旨在为推进我国临床试验数据的标准化工作提供借鉴。
文摘为满足企业经营管理对财务月报准确、严谨、快速和高效报送的需求,设计一种基于SAP BW(SAP Business Warehouse)的财务快月报平台。针对现有报表在出具、调整和报送方面存在的突出问题,阐述该平台的总体框架和设计思路,以及报表展现和报表报送解决方案。实际应用结果表明,基于SAP BW的财务快月报平台既能满足财务报表的准确性要求,又能兼顾报表报送的严谨性和快速性,同时具有良好的可操作性和可推广性,可供同类项目的设计开发参考。
