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Powe宿命论量表的汉化及信效度检验 被引量:1
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作者 沈芳 杨福军 +1 位作者 谭秋 付艳芬 《全科护理》 2024年第12期2194-2198,共5页
目的:汉化Powe宿命论量表(Powe Fatalism Inventory, PFI),并在结直肠癌高危人群中进行信效度检验。方法:依据Beaton跨文化调试指南对量表进行翻译、回译、跨文化调试及预试验形成中文版Powe宿命论量表。于2022年9月18日—2023年2月18... 目的:汉化Powe宿命论量表(Powe Fatalism Inventory, PFI),并在结直肠癌高危人群中进行信效度检验。方法:依据Beaton跨文化调试指南对量表进行翻译、回译、跨文化调试及预试验形成中文版Powe宿命论量表。于2022年9月18日—2023年2月18日选取348例云南省10所医院的肿瘤科及其中1所医院的普外科和消化内科40~74岁的结直肠癌高危人群进行问卷调查,验证量表的信效度。结果:中文版Powe宿命论量表共4个维度,15个条目,分别为先定(7个条目)、死亡的必然性(3个条目)、悲观(3个条目)、恐惧(2个条目)。总量表的Cronbach′s α系数为0.853,各维度的Cronbach′s α系数为0.582~0.836;总量表的折半信度为0.845,总量表的重测信度为0.823,各维度的重测信度为0.514~0.794。验证性因子分析结果显示,模型拟合度良好。结论:中文版Powe宿命论量表具有良好的信度和效度,可以用来测量结直肠癌高危人群的癌症宿命论水平。 展开更多
关键词 宿命论 癌症 结直肠癌 高危人群 powe宿命论量表
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PowerPlex 16 HS试剂盒在陈旧血样DNA检验中的应用
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作者 周密 唐涛 +2 位作者 张韩秋 丁仁杰 王成权 《中国法医学杂志》 CSCD 北大核心 2011年第3期224-225,共2页
PowerPlex16HS系统是对16个STR基因座进行联合扩增试剂盒,对PCR抑制物的耐受性较强,适于直接扩增^[1-2]。本文作者在公安部的打拐专项行动中,采用该试剂盒,对保存近10年的300份陈旧血样进行DNA检验,取得了较好的效果。
关键词 法医物证学 陈旧血样 直接扩增 powe rPlex16 Hs试剂盒
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PowerPoint课件中插入Flash动画及其存取与播放 被引量:2
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作者 田丰 《中国现代教育装备》 2006年第12期127-129,共3页
本文总结了PowerPoint课件中插入Flash动画及其存取与播放的一些方法技巧。
关键词 powe rPoint FLASH动画 插入 存取 播放
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用PowerPoint制作平抛运动的演示课件 被引量:1
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作者 熊天信 《中国现代教育装备》 2009年第5期31-32,共2页
本文介绍应用PowerPoint 2003制作平抛运动的演示课件,给出了详细的制作过程和方法,课件效果较好,制作过程简单易学,对于只学习过PowerPoint的教师不失为一个较好的方法。
关键词 平抛运动 powe rPoint 2003 课件
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Research on Impact Mechanism and Power System of Urbanization in West China 被引量:1
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作者 WU Xiao, ZHANG Pei College of Architecture, Xi’an University of Architecture and Technology, Xi’an 710055, China 《Asian Agricultural Research》 2011年第12期56-61,共6页
Based on the current situation of urbanization development in West China, this paper analyses main factors responsible for sluggish urbanization in West China as follows: impact of environment factor, impact of popula... Based on the current situation of urbanization development in West China, this paper analyses main factors responsible for sluggish urbanization in West China as follows: impact of environment factor, impact of population quality and quantity, lagging of public product service, stagnancy of technological development, backwardness of slow growth, and rigidity of system building. And then this paper analyses the restriction mechanism of urbanization in West China: at the superficial level, the constraints of urbanization in West China arise from the shortage of capital; at the profound level, the backward culture contributes to the constraints of urbanization in West China. The thread of resolving restriction mechanism of urbanization in West China is put forward from system, economy and culture. On the basis of this thread, we construct the power system for the development of urbanization in West China. The power system for urbanization in West China should be propelled by "four forces", namely, pull of external forces, cohesive strength of regional market environment, expansion power inside countryside, traction of industrial structure adjustment. Innovation is the engine of impetus for urbanization in West China; spatial clustering and modernization of industry is the major driving force for urbanization; the government behaviour, driving of foreign investment, great projects and other forces are supplementary power. Via the main power, we should take the market as medium to achieve the role of power in promoting urbanization. 展开更多
关键词 WEST China URBANIZATION RESTRICTION MECHANISM powe
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Predictive power of statistical significance
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作者 Thomas F Heston Jackson M King 《World Journal of Methodology》 2017年第4期112-116,共5页
A statistically significant research finding should not be defined as a P-value of 0.05 or less, because this definition does not take into account study power. Statistical significance was originally defined by Fishe... A statistically significant research finding should not be defined as a P-value of 0.05 or less, because this definition does not take into account study power. Statistical significance was originally defined by Fisher RA as a P-value of 0.05 or less. According to Fisher, any finding that is likely to occur by random variation no more than 1 in 20 times is considered significant. Neyman J and Pearson ES subsequently argued that Fisher's definition was incomplete. They proposed that statistical significance could only be determined by analyzing the chance of incorrectly considering a study finding was significant(a Type Ⅰ?error) or incorrectly considering a study finding was insignificant(a Type Ⅱ error). Their definition of statistical significance is also incomplete because the error rates are considered separately, not together. A better definition of statistical significance is the positive predictive value of a P-value, which is equal to the power divided by the sum of power and the P-value. This definition is more complete and relevant than Fisher's or Neyman-Peason's definitions, because it takes into account both concepts of statistical significance. Using this definition, a statistically significant finding requires a P-value of 0.05 or less when the power is at least 95%, and a P-value of 0.032 or less when the power is 60%. To achieve statistical significance, P-values must be adjusted downward as the study power decreases. 展开更多
关键词 Statistical significance Positive predictive value BIOSTATISTICS Clinical signifcance powe
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Echoes of the Lisbon Maru
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作者 LI WENYU 《China Today》 2025年第9期32-35,共4页
ON May 20,2025,eighteen descendants of British prisoners of war(POWs)rescued in the Lisbon Maru incident arrived on Dongji Island in east China’s Zhejiang Province,after a long transoceanic journey.They joined descen... ON May 20,2025,eighteen descendants of British prisoners of war(POWs)rescued in the Lisbon Maru incident arrived on Dongji Island in east China’s Zhejiang Province,after a long transoceanic journey.They joined descendants of the local fishermen who had saved their ancestors 83 years ago,gathering to witness the unveiling of a memorial erected in honor of the fishermen’s extraordinary bravery.At its center,the memorial bears the inscription:“Love knows no boundaries;Friendship transcends time.” 展开更多
关键词 lisbon maru incident prisoners war pows rescued Zhejiang province Dongji Island DESCENDANTS British prisoners war MEMORIAL transoceanic journeythey
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Three key policy areas in urgent need of improvement for advancing China’s energy transition
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作者 Peng Li Jing Zhang 《iEnergy》 2025年第2期77-78,共2页
Remarkable achievements of the new energy industry policy framework over the past two decades Over the past two decades,the industry policy framework centered on the Renewable Energy Law has effectively facilitated th... Remarkable achievements of the new energy industry policy framework over the past two decades Over the past two decades,the industry policy framework centered on the Renewable Energy Law has effectively facilitated the leapfrog development of China’s new energy sector.During this period,policy incentives were primarily focused on promoting the rational scaling of the industry,thereby driving rapid technological upgrades and iterations.This,in turn,enabled a significant reduc-tion in the cost of new energy power generation.In this process,policy played a pivotal role in two key areas:first,by providing per-kilowatt-hour subsidies to bridge the cost gap between new energy and conventional power sources;and second,by exempting the system cost of new energy grid-connected operation through a full guaranteed purchase system. 展开更多
关键词 new energy new energy pow policy framework renewable energy law energy transition new energy industry industry policy framework
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PoW管理系统下客户端动态升级策略及其对网络加速的影响
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作者 赵炜 《中国宽带》 2025年第1期157-159,共3页
随着区块链技术的快速发展,工作量证明(Proof of Work, PoW)共识机制作为其核心组成部分,在确保网络安全性与去中心化方面扮演着重要的角色。PoW管理系统的稳定性和效率直接影响到整个区块链网络的性能和可扩展性,如何应用和优化客户端... 随着区块链技术的快速发展,工作量证明(Proof of Work, PoW)共识机制作为其核心组成部分,在确保网络安全性与去中心化方面扮演着重要的角色。PoW管理系统的稳定性和效率直接影响到整个区块链网络的性能和可扩展性,如何应用和优化客户端软件的动态升级策略变得尤为关键。本文从PoW共识机制的基本原理出发,分析PoW管理系统下的客户端动态升级策略,进而探讨其对网络加速的影响,以期为实现更高效、更安全的区块链网络提供理论支持和实践指导。 展开更多
关键词 PoW共识机制 客户端动态升级 网络加速 区块链技术
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Game theory attack pricing for mining pools in blockchain-based IoT
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作者 Yourong Chen Hao Chen +3 位作者 Zhenyu Xiong Banteng Liu Zhangquan Wang Meng Han 《Digital Communications and Networks》 SCIE CSCD 2024年第4期973-988,共16页
The malicious mining pool can sacrifice part of its revenue to employ the computing power of blockchain network.The employed computing power carries out the pool mining attacks on the attacked mining pool.To realize t... The malicious mining pool can sacrifice part of its revenue to employ the computing power of blockchain network.The employed computing power carries out the pool mining attacks on the attacked mining pool.To realize the win-win game between the malicious mining pool and the employee,the paper proposes an Employment Attack Pricing Algorithm(EAPA)of mining pools in blockchain based on game theory.In the EAPA,the paper uses mathematical formulas to express the revenue of malicious mining pools under the employment attack,the revenue increment of malicious mining pools,and the revenue of the employee.It establishes a game model between the malicious mining pool and the employee under the employment attack.Then,the paper proposes an optimal computing power price selection strategy of employment attack based on model derivation.In the strategy,the malicious mining pool analyzes the conditions for the employment attack,and uses the derivative method to find the optimal utilization value of computing power,employees analyze the conditions for accepting employment,and use the derivative method to find the optimal reward value of computing power.Finally,the strategy finds the optimal employment computing power price to realize Nash equilibrium between the malicious mining pool and the employee under the current computing power allocation.The simulation results show that the EAPA could find the employment computing power price that realizes the win-win game between the malicious mining pool and the employee.The EAPA also maximizes the unit computing power revenue of employment and the unit computing power revenue of honest mining in malicious mining pool at the same time.The EAPA outperforms the state-of-the-art methods such as SPSUCP,DPSACP,and FPSUCP. 展开更多
关键词 Game theory Blockchain PoW Mining pool Employment attack
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A Systematic Literature Review on Blockchain Consensus Mechanisms’ Security: Applications and Open Challenges
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作者 Muhammad Muntasir Yakubu Mohd Fadzil B Hassan +5 位作者 Kamaluddeen Usman Danyaro Aisha Zahid Junejo Muhammed Siraj Saidu Yahaya Shamsuddeen Adamu Kamal Abdulsalam 《Computer Systems Science & Engineering》 2024年第6期1437-1481,共45页
This study conducts a systematic literature review(SLR)of blockchain consensus mechanisms,an essential protocols that maintain the integrity,reliability,and decentralization of distributed ledger networks.The aim is t... This study conducts a systematic literature review(SLR)of blockchain consensus mechanisms,an essential protocols that maintain the integrity,reliability,and decentralization of distributed ledger networks.The aim is to comprehensively investigate prominent mechanisms’security features and vulnerabilities,emphasizing their security considerations,applications,challenges,and future directions.The existing literature offers valuable insights into various consensus mechanisms’strengths,limitations,and security vulnerabilities and their real-world applications.However,there remains a gap in synthesizing and analyzing this knowledge systematically.Addressing this gap would facilitate a structured approach to understanding consensus mechanisms’security and vulnerabilities comprehensively.The study adheres to Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines and computer science standards and reviewed 3749 research papers from 2016 to 2024,excluding grey literature,resulting in 290 articles for descriptive analysis.The research highlights an increased focus on blockchain consensus security,energy efficiency,and hybrid mechanisms within 60%of research papers post-2019,identifying gaps in scalability,privacy,and interoperability for future exploration.By synthesizing the existing research and identifying the key trends,this SLR contributes to advancing the understanding of blockchain consensus mechanisms’security and guiding future research and structured innovation in blockchain systems and applications. 展开更多
关键词 Blockchain consensus mechanisms supply chain management proof of work(PoW) proof of stake(PoS) practical byzantine fault tolerance(PBFT)
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面向能源区块链的分布式电力交易系统设计
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作者 谢文 嵇士杰 +2 位作者 纪鹏 齐宇蓉 王赢方 《微型电脑应用》 2024年第8期96-99,共4页
研究能源区块链驱动的分布式电力交易系统设计。通过整合POW共识算法的电力交易工作流程、能源区块链平台的架构探索以及优化电力交易流程,探讨分布式电力市场的可行性和经济潜力。研究结果表明,太阳能光伏发电功率与挖矿成本之间存在... 研究能源区块链驱动的分布式电力交易系统设计。通过整合POW共识算法的电力交易工作流程、能源区块链平台的架构探索以及优化电力交易流程,探讨分布式电力市场的可行性和经济潜力。研究结果表明,太阳能光伏发电功率与挖矿成本之间存在密切联系,需要根据光照和功率波动调整电力交易策略以降低成本。改进的连续双向拍卖模式通过智能合约提高了交易效率,同时区块链技术确保了交易的安全和透明性,可以为未来电力市场的可持续性和创新提供参考。 展开更多
关键词 能源区块链 分布式电力交易系统 POW共识算法
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高压直流换流站分合闸控制装置故障分析 被引量:17
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作者 冯鸫 杨洁民 罗海志 《高电压技术》 EI CAS CSCD 北大核心 2008年第8期1751-1754,共4页
为了减少直流输电系统投切交流滤波器过程中产生的带有直流分量的涌流和操作电压,以及减少投切换流变压器和站用变压器产生的励磁涌流,兴仁换流站采用了分合闸控制POW装置控制其分合。介绍了POW装置的工作原理、控制策略,讨论了实际运行... 为了减少直流输电系统投切交流滤波器过程中产生的带有直流分量的涌流和操作电压,以及减少投切换流变压器和站用变压器产生的励磁涌流,兴仁换流站采用了分合闸控制POW装置控制其分合。介绍了POW装置的工作原理、控制策略,讨论了实际运行中POW装置出现的多种故障,分析了POW装置出现故障的原因,并对POW装置的运行维护提出了建议。结合一年的运行经验,对比未安装之前,投切交流滤波器减少了60%操作电压,投切变压器减少了80%的励磁涌流。结果表明,使用POW装置效果较好。 展开更多
关键词 高压直流输电 选相分合闸 分合闸控制 POW装置 断路器 励磁涌流
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基于新型区块的售票系统的设计与实现 被引量:3
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作者 陈梅 张文冲 +1 位作者 钱育蓉 李自臣 《信息技术》 2020年第8期28-33,38,共7页
以电影院售票系统为例,将区块链技术应用于传统电影院售票系统,设计并实现了基于新型区块的电影院售票系统。在以太坊上实验结果表明,新型区块存储的数据量高于传统区块存储数据量3.95倍。基于新型区块的电影院售票系统,改进了传统电影... 以电影院售票系统为例,将区块链技术应用于传统电影院售票系统,设计并实现了基于新型区块的电影院售票系统。在以太坊上实验结果表明,新型区块存储的数据量高于传统区块存储数据量3.95倍。基于新型区块的电影院售票系统,改进了传统电影院售票系统存在的数据被篡改、虚假票房、偷税漏税等缺陷,为区块链技术在售票系统中的应用提供参考。 展开更多
关键词 区块链 POW共识机制 防篡改 以太坊 新型区块
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一种基于区块链PoS共识算法的改进研究 被引量:12
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作者 钟增胜 《重庆工商大学学报(自然科学版)》 2021年第4期36-41,共6页
区块链共识算法保证了区块链中的区块按时间戳有序生成,算法优劣直接影响区块链系统性能。PoS共识算法是一种区块链公有链采用的主流共识算法,但生成区块的时间具有随机性,有些情况下区块间隔时间过长,不能满足商业应用场景需要;针对Po... 区块链共识算法保证了区块链中的区块按时间戳有序生成,算法优劣直接影响区块链系统性能。PoS共识算法是一种区块链公有链采用的主流共识算法,但生成区块的时间具有随机性,有些情况下区块间隔时间过长,不能满足商业应用场景需要;针对PoS共识算法生成区块的速度存在的性能局限,改进设计的Silkworm算法,通过智能合约对最快生成区块时间和最慢生成区块时间进行定义,结合Raft算法进行主节点选举;在有交易的情况下,当PoS共识算法未在定义的最快时间内生成区块时,Silkworm算法确保由主节点自动快速生成区块;在无交易情况下,当PoS共识算法未在定义的最慢时间内生成区块时,Silkworm算法也由主节点生成区块。而当主节点关闭或出故障时,PoS共识算法仍然生效正常生成区块。通过实验验证:Silkworm算法能较大提升基于PoS共识算法的区块链的性能,保证了区块链的安全性和健壮性,更能满足商业应用场景的需要。 展开更多
关键词 区块链 共识算法 POS PoW RAFT
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区块链技术与应用前瞻综述 被引量:517
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作者 何蒲 于戈 +1 位作者 张岩峰 鲍玉斌 《计算机科学》 CSCD 北大核心 2017年第4期1-7,15,共8页
区块链技术是一种去中心化、去信任化的分布式数据库技术方案。该数据库由参与系统的所有节点集体维护,具有去中心化、不可篡改、透明、安全等特性。区块链技术归功于比特币应用,它作为比特币的底层技术支持,是比特币系统的核心支撑。... 区块链技术是一种去中心化、去信任化的分布式数据库技术方案。该数据库由参与系统的所有节点集体维护,具有去中心化、不可篡改、透明、安全等特性。区块链技术归功于比特币应用,它作为比特币的底层技术支持,是比特币系统的核心支撑。区块链技术具有广阔的发展前景,从关键技术、内容、原理、瓶颈、应用和前景几个方面进行介绍,对相关研究问题进行探讨。 展开更多
关键词 区块链 比特币 MERKLE树 POW共识 智能合约
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The Research and Development to Glasses to See the Cancer Cells
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《科技传播》 2014年第4期15-15,共1页
Cancer cells are notoriously difficult to see,even under high-powered magnification(放大).The glasses are designed to make it easier for surgeons to distinguish cancer cells from healthy cells,helping to ensure that n... Cancer cells are notoriously difficult to see,even under high-powered magnification(放大).The glasses are designed to make it easier for surgeons to distinguish cancer cells from healthy cells,helping to ensure that no stray tumor cells are left behind during surgery."We’re in the early stages of this technology,and more development and testing will be done,but we’re certainly 展开更多
关键词 DISTINGUISH encouraged HELPING GLASSES behind powe
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基于有向无环图的高效区块链共识算法 被引量:11
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作者 王壹铭 初剑峰 +1 位作者 王永军 陈彦东 《吉林大学学报(理学版)》 CAS 北大核心 2020年第5期1167-1172,共6页
针对传统区块链共识算法存在效率低和大量资源浪费的问题,提出一种使用基于ID分类的有向无环图数据结构取代传统区块链链式数据结构的算法,解决了传统区块链项目无法在短时间内确认大量交易的问题.该算法使用基于ID分类的有向无环图数... 针对传统区块链共识算法存在效率低和大量资源浪费的问题,提出一种使用基于ID分类的有向无环图数据结构取代传统区块链链式数据结构的算法,解决了传统区块链项目无法在短时间内确认大量交易的问题.该算法使用基于ID分类的有向无环图数据结构能更简单地达成共识,适用于多用户在同一时间进行交易确认.该共识算法与传统区块链项目相比能在更短的时间内确认交易,从而可节省大量的硬件资源,且提升区块链对交易的处理效率. 展开更多
关键词 区块链 共识算法 工作量证明(PoW) 股权证明(PoS) 实用拜占庭容错(PBFT)
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基于Go语言的区块链模型设计与实现
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作者 刘敏娜 尹成 姚波 《数字技术与应用》 2021年第2期159-161,共3页
研究区块链技术原理、特点及POW工作量证明算法,构建基于Go语言的区块链模型,实现挖矿、交易数据打包、区块上链等操作。为了保证交易数据的安全性,模型对区块数据哈希校验,检验数据是否被篡改。在仿真实验中,使用Postman软件对指定端... 研究区块链技术原理、特点及POW工作量证明算法,构建基于Go语言的区块链模型,实现挖矿、交易数据打包、区块上链等操作。为了保证交易数据的安全性,模型对区块数据哈希校验,检验数据是否被篡改。在仿真实验中,使用Postman软件对指定端口进行post和get操作,实验结果证明,模型能完成工作量计算,能够实现交易数据上链等操作。 展开更多
关键词 区块链 POW 交易数据 哈希运算
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基于信用模型的工作量证明算法 被引量:11
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作者 王缵 田有亮 +1 位作者 李秋贤 杨新欢 《通信学报》 EI CSCD 北大核心 2018年第8期185-198,共14页
提出了一种基于信用模型的共识协议。首先,该共识协议借鉴了个人信用风险评估的思想,设计了一种基于BP神经网络的节点信用度模型。其次,构造了一种分片轮转模型,它可以根据节点的信用度高低分割搜索空间产生新区块,同时对协议所面临的... 提出了一种基于信用模型的共识协议。首先,该共识协议借鉴了个人信用风险评估的思想,设计了一种基于BP神经网络的节点信用度模型。其次,构造了一种分片轮转模型,它可以根据节点的信用度高低分割搜索空间产生新区块,同时对协议所面临的可能攻击进行分析,修复了协议存在的漏洞。最后,仿真实验表明共识协议既能有效地降低新区块产生过程中重复计算的巨大资源消耗,也能抑制大型矿池的产生,使整个区块链系统变得更加安全可靠。 展开更多
关键词 PoW共识 BP神经网络 信用度模型 搜索空间 区块链
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