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Quantum discord and its dynamics for multipartite systems
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作者 罗嘉欣 郭琼 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期168-175,共8页
Quantum discord, one of the famous quantum correlations, has been recently generalized to multipartite systems by Radhakrishnan et al. Here we give analytical solutions of the quantum discord for a family of N-qubit q... Quantum discord, one of the famous quantum correlations, has been recently generalized to multipartite systems by Radhakrishnan et al. Here we give analytical solutions of the quantum discord for a family of N-qubit quantum states. For the bipartite system, we derive a zero quantum discord which will remain unchanged under the phase damping channel. For multiparitite systems, it is found that the quantum discord can be classified into three categories and the quantum discord for odd-partite systems can exhibit freezing under the phase damping channel, while the freezing does not exist in the even-partite systems. 展开更多
关键词 quantum discord multipartite systems decoherence channels frozen discord
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Robust adaptive leaderless consensus of unknown non-minimum phase linear multi-agent systems subject to disturbances and/or unmodeled dynamics
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作者 Wenji Cao Gang Feng 《Journal of Automation and Intelligence》 2024年第2期92-100,共9页
This article investigates the problem of robust adaptive leaderless consensus for heterogeneous uncertain nonminimumphase linear multi-agent systems over directed communication graphs. Each agent is assumed tobe of un... This article investigates the problem of robust adaptive leaderless consensus for heterogeneous uncertain nonminimumphase linear multi-agent systems over directed communication graphs. Each agent is assumed tobe of unknown nominal dynamics and also subject to external disturbances and/or unmodeled dynamics. Anovel distributed robust adaptive control strategy is proposed. It is shown that the robust adaptive leaderlessconsensus problem is solved with the proposed control strategy under some sufficient conditions. Two examplesare provided to demonstrate the efficacy of the proposed control strategy. 展开更多
关键词 Cooperative control Non-minimum phase Leaderless consensus Multi-agent systems Robust adaptive control
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ZIF-67/CS对阳离子染料孔雀石绿的吸附性能研究
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作者 娄杰 付秋平 +4 位作者 余磊 云驰 李霜颖 罗丹 李茂海 《现代化工》 CAS CSCD 北大核心 2024年第6期168-174,共7页
针对传统吸附剂与水相分离困难的问题,设计并制备了一种环境友好、成本低廉的壳聚糖复合材料ZIF-67/CS。针对吸附剂对孔雀石绿(MG)污染物的吸附性能,考察了污染物浓度、接触时间、吸附剂用量、pH和离子强度对其吸附性能的影响。利用XRD... 针对传统吸附剂与水相分离困难的问题,设计并制备了一种环境友好、成本低廉的壳聚糖复合材料ZIF-67/CS。针对吸附剂对孔雀石绿(MG)污染物的吸附性能,考察了污染物浓度、接触时间、吸附剂用量、pH和离子强度对其吸附性能的影响。利用XRD、SEM、FT-IR、TG等对其结构、形貌及热稳定性进行了表征。结果表明,在吸附实验中,303.15 K时ZIF-67/CS对MG的吸附等温线符合Temkin等温吸附模型;吸附动力学拟合结果表明,ZIF-67/CS对MG的吸附行为符合拟二级吸附动力学模型;吸附热力学结果表明吸附过程是自发的、吸热的。ZIF-67/CS对MG的吸附是一个复杂的化学吸附过程,主要由速率决定。 展开更多
关键词 ZIF-67/cs ZIF-67 壳聚糖 孔雀石绿 吸附
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基于MCS-SBL算法的配电网故障定位方法
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作者 周群 刘梓琳 +2 位作者 冷敏瑞 印月 何川 《电力系统及其自动化学报》 CSCD 北大核心 2024年第3期30-38,共9页
配电网拓扑结构复杂,传统方法往往需要大量测点信息且难以实现快速有效的故障定位,本文提出基于少量测点信息的故障定位方法。首先,利用等效原理建立一个欠定的故障节点电压方程;其次,利用多重测量向量模型的贝叶斯压缩感知算法求解方程... 配电网拓扑结构复杂,传统方法往往需要大量测点信息且难以实现快速有效的故障定位,本文提出基于少量测点信息的故障定位方法。首先,利用等效原理建立一个欠定的故障节点电压方程;其次,利用多重测量向量模型的贝叶斯压缩感知算法求解方程,根据重构稀疏电流矩阵的非零元素位置求解故障区域,实现故障定位;最后,在IEEE33节点配电系统上进行仿真实验,结果表明,所提方法仅需要少量测点的故障前后正序电压分量便可有效定位故障,计算速度较快,并且基本不受故障类型、过渡电阻的影响,同时适用于单故障和多重故障的场景,具有较强的抗噪能力。 展开更多
关键词 配电网 故障定位 多重测量向量模型 稀疏电流 压缩感知
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用于碳酸盐岩储层裂缝检测的GWO-CS-BP算法及应用研究
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作者 李琼 张宇 石林坤 《石油物探》 CSCD 北大核心 2024年第4期833-845,共13页
碳酸盐岩储层中的裂隙是油气的运移通道和储集空间,对于油气勘探、开发和评价都具有重要的指导意义。针对研究区碳酸盐岩储层裂缝检测的难题,提出灰狼布谷鸟优化BP算法(GWO-CS-BP),该算法是将GWO-CS(grey wolf-cuckoo search algorithm)... 碳酸盐岩储层中的裂隙是油气的运移通道和储集空间,对于油气勘探、开发和评价都具有重要的指导意义。针对研究区碳酸盐岩储层裂缝检测的难题,提出灰狼布谷鸟优化BP算法(GWO-CS-BP),该算法是将GWO-CS(grey wolf-cuckoo search algorithm)与BP(back propagation)相结合形成的裂隙检测方法。将含裂缝信息的相干、曲率、倾角、方位角和构型张量等属性作为GWO-CS-BP神经网络的输入数据,在工区地质资料约束下根据测井数据获得裂缝发育水平评价指标,进而对研究区裂缝发育水平进行评价并划分等级。研究区碳酸盐岩储层裂缝发育水平检测结果表明,GWO-CS-BP算法能够综合各属性特点对研究区的裂缝发育水平特征进行二次误差控制,获得裂缝发育水平评价指标f s并将研究区裂缝发育水平划分为3个等级及4个裂缝存在区域。其中,当研究区裂缝发育水平参数的值适中时,即f s的值大于4.0且小于5.8时,C区域最有利于油气的聚集,高产井的分布数量较多。利用GWO-CS-BP算法对研究区的裂缝发育水平进行了精细评价,并得出裂隙发育水平参数f s,实现了GWO-CS算法改进的BP神经网络在裂缝检测中的有效应用。 展开更多
关键词 地震属性 裂缝检测 GWO-cs优化算法 BP神经网络 碳酸盐岩储层
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Cs/O沉积Na_(2)KSb光电阴极表面的第一性原理研究
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作者 王麒铭 张益军 +5 位作者 王兴超 王亮 金睦淳 任玲 刘晓荣 钱芸生 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第8期341-349,共9页
Na_(2)KSb光电阴极在光电倍增管、图像增强器、真空电子源等领域具有重要应用.为指导高灵敏度Na_(2)KSb光电阴极的制备,采用第一性原理计算方法,研究不同表面取向和原子终止面的Na_(2)KSb表面模型,获得稳定且最有利于电子发射的表面结构... Na_(2)KSb光电阴极在光电倍增管、图像增强器、真空电子源等领域具有重要应用.为指导高灵敏度Na_(2)KSb光电阴极的制备,采用第一性原理计算方法,研究不同表面取向和原子终止面的Na_(2)KSb表面模型,获得稳定且最有利于电子发射的表面结构.基于该表面进一步研究了不同覆盖度下的Cs原子沉积和Cs/O原子共沉积对Na_(2)KSb表面电子结构和光学性质的影响.对比表面能、吸附能和吸附前后的功函数结果表明,Na_(2)KSb(111)K表面具有优越的电子发射能力以及良好的稳定性.当Na_(2)KSb(111)K表面吸附2/4单层的Cs原子和1/4单层O原子时,获得最大功函数下降量0.16 eV.表面吸附Cs/O原子有利于电荷往表面上方转移,并产生电荷累积,能形成有效表面偶极矩.通过分析能带结构和态密度,发现吸附Cs原子对导带底存在额外的能带贡献,且引入O原子吸附后价带发生上移.此外,吸附Cs/O原子有利于增强表面近红外光吸收,但是会导致表面紫外和可见光吸收变差. 展开更多
关键词 Na_(2)KSb 光电阴极 cs/O沉积 功函数 偶极矩
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Integrative multi-omics and systems bioinformatics in translational neuroscience:A data mining perspective 被引量:1
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作者 Lance M.O'Connor Blake A.O'Connor +2 位作者 Su Bin Lim Jialiu Zeng Chih Hung Lo 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第8期836-850,共15页
Bioinformatic analysis of large and complex omics datasets has become increasingly useful in modern day biology by providing a great depth of information,with its application to neuroscience termed neuroinformatics.Da... Bioinformatic analysis of large and complex omics datasets has become increasingly useful in modern day biology by providing a great depth of information,with its application to neuroscience termed neuroinformatics.Data mining of omics datasets has enabled the generation of new hypotheses based on differentially regulated biological molecules associated with disease mechanisms,which can be tested experimentally for improved diagnostic and therapeutic targeting of neurodegenerative diseases.Importantly,integrating multi-omics data using a systems bioinformatics approach will advance the understanding of the layered and interactive network of biological regulation that exchanges systemic knowledge to facilitate the development of a comprehensive human brain profile.In this review,we first summarize data mining studies utilizing datasets from the individual type of omics analysis,including epigenetics/epigenomics,transcriptomics,proteomics,metabolomics,lipidomics,and spatial omics,pertaining to Alzheimer's disease,Parkinson's disease,and multiple sclerosis.We then discuss multi-omics integration approaches,including independent biological integration and unsupervised integration methods,for more intuitive and informative interpretation of the biological data obtained across different omics layers.We further assess studies that integrate multi-omics in data mining which provide convoluted biological insights and offer proof-of-concept proposition towards systems bioinformatics in the reconstruction of brain networks.Finally,we recommend a combination of high dimensional bioinformatics analysis with experimental validation to achieve translational neuroscience applications including biomarker discovery,therapeutic development,and elucidation of disease mechanisms.We conclude by providing future perspectives and opportunities in applying integrative multi-omics and systems bioinformatics to achieve precision phenotyping of neurodegenerative diseases and towards personalized medicine. 展开更多
关键词 Multi-omics integration systems bioinformatics Data mining Human brain profile reconstruction Translational neuroscience
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基于绿色低共熔溶剂CS-1的TATB新型纯化方法与机理
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作者 左依文 陈建波 +2 位作者 刘晓峰 刘渝 索志荣 《含能材料》 EI CAS CSCD 北大核心 2024年第7期745-753,共9页
为了解决TATB因溶解性差不适用于常规纯化方法的问题,采用反萃取技术,选用对TATB具有良好溶解性的新型绿色低共熔溶剂(CS-1),以水为反萃取剂,进行了TATB的纯化;对比了该法与其它纯化方法的不同,系统优化了该法中反萃取剂加入量、洗涤次... 为了解决TATB因溶解性差不适用于常规纯化方法的问题,采用反萃取技术,选用对TATB具有良好溶解性的新型绿色低共熔溶剂(CS-1),以水为反萃取剂,进行了TATB的纯化;对比了该法与其它纯化方法的不同,系统优化了该法中反萃取剂加入量、洗涤次数及干燥方式等条件对TATB的纯化影响,构建了纯度为(99.7±0.2)%,回收率为92.5%的TATB高效分离与绿色纯化方法。研究同时采用光谱过程监测和理论计算模拟,基于CS-1溶剂的TATB纯化动力学,探讨了基于氢键竞争和络合物解离的TATB纯化机制。 展开更多
关键词 1 3 5-三氨基-2 4 6-三硝基苯 cs-1溶剂 反萃取技术 纯化机制
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About the Thermodynamics and Aging of Self-Organizing Systems
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作者 Jorge Barragán Sebastián Sánchez 《Advances in Aging Research》 2023年第4期56-66,共11页
We know that the total daily energy dissipation increases in complex organisms like the humans. It’s very probable that this increase in total energy dissipation is related to the progressive increase in mass. But we... We know that the total daily energy dissipation increases in complex organisms like the humans. It’s very probable that this increase in total energy dissipation is related to the progressive increase in mass. But we also know that day by day the dissipation of energy per unit mass decreases in these organisms. We intend to verify if this decrease is only an expression of the second law of thermodynamics, or if it is related to the increase in mass that occurs in these organisms. For this, we set ourselves the following objectives: verify the correlation between total energy dissipation and the evolution of body mass, and verify the correlation between the dissipation of energy per unit of mass and the evolution of body mass. As a result of the data analysis, we found a high degree of correlation between total energy dissipation and the evolution of body mass. And we also found a high correlation between the energy dissipated per unit of mass and the evolution of body mass. We can conclude that self-organization produces not only an increase in mass, but also a decline in energy dissipation per unit mass beyond what is expected by the second law of thermodynamics. 展开更多
关键词 Body Mass Energy Dissipation Neutral Operator Structural Geometry Information Density Inertial systems Non-Inertial systems
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Mo掺杂对笼目超导体CsV_(3)Sb_(5)结构和电磁性能的影响
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作者 李映 向峻杰 +1 位作者 杨帆 陈永亮 《广州化工》 CAS 2024年第8期115-118,141,共5页
新型笼目金属CsV_(3)Sb_(5)(A=K, Rb, Cs)作为一个具有多种电子序耦合与竞争的平台,其丰富的物理特性备受关注。本文用新开发的以CsCl为辅助熔剂制备了不同掺Mo含量的Cs(V_(1-x)Mo_(x))3Sb5多晶样品,并通过对XRD数据进行Rietveld分析获... 新型笼目金属CsV_(3)Sb_(5)(A=K, Rb, Cs)作为一个具有多种电子序耦合与竞争的平台,其丰富的物理特性备受关注。本文用新开发的以CsCl为辅助熔剂制备了不同掺Mo含量的Cs(V_(1-x)Mo_(x))3Sb5多晶样品,并通过对XRD数据进行Rietveld分析获得了其晶格结构信息,通过测量各样品的磁化强度及电阻率随温度变化关系,对其磁性和电输运性质进行了表征和分析。结果表明,随着Mo的掺入,母相CsV_(3)Sb_(5)的晶格常数a和晶胞体积略微增大,锑烯层中的Sb2原子会逐渐偏离笼目层。同时,体系的超导电性被抑制,而电荷密度波转变温度却增大,二者呈相互竞争关系。 展开更多
关键词 笼目金属 cs(V_(1-x)Mo_(x))_(3)Sb_(5) 晶格结构 电磁性质
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Computational Experiments for Complex Social Systems:Experiment Design and Generative Explanation 被引量:1
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作者 Xiao Xue Deyu Zhou +5 位作者 Xiangning Yu Gang Wang Juanjuan Li Xia Xie Lizhen Cui Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期1022-1038,共17页
Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a nove... Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system emergence.To address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating laws.Finally,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”. 展开更多
关键词 Agent-based modeling computational experiments cyber-physical-social systems(CPSS) generative deduction generative experiments meta model
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Hybridization of Metaheuristics Based Energy Efficient Scheduling Algorithm for Multi-Core Systems
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作者 J.Jean Justus U.Sakthi +4 位作者 K.Priyadarshini B.Thiyaneswaran Masoud Alajmi Marwa Obayya Manar Ahmed Hamza 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期205-219,共15页
The developments of multi-core systems(MCS)have considerably improved the existing technologies in thefield of computer architecture.The MCS comprises several processors that are heterogeneous for resource capacities,... The developments of multi-core systems(MCS)have considerably improved the existing technologies in thefield of computer architecture.The MCS comprises several processors that are heterogeneous for resource capacities,working environments,topologies,and so on.The existing multi-core technology unlocks additional research opportunities for energy minimization by the use of effective task scheduling.At the same time,the task scheduling process is yet to be explored in the multi-core systems.This paper presents a new hybrid genetic algorithm(GA)with a krill herd(KH)based energy-efficient scheduling techni-que for multi-core systems(GAKH-SMCS).The goal of the GAKH-SMCS tech-nique is to derive scheduling tasks in such a way to achieve faster completion time and minimum energy dissipation.The GAKH-SMCS model involves a multi-objectivefitness function using four parameters such as makespan,processor utilization,speedup,and energy consumption to schedule tasks proficiently.The performance of the GAKH-SMCS model has been validated against two datasets namely random dataset and benchmark dataset.The experimental outcome ensured the effectiveness of the GAKH-SMCS model interms of makespan,pro-cessor utilization,speedup,and energy consumption.The overall simulation results depicted that the presented GAKH-SMCS model achieves energy effi-ciency by optimal task scheduling process in MCS. 展开更多
关键词 Task scheduling energy efficiency multi-core systems fitness function MAKESPAN
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Foundations and Applications of Information Systems Dynamics
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作者 Jianfeng Xu Zhenyu Liu +4 位作者 Shuliang Wang Tao Zheng Yashi Wang Yingfei Wang Yingxu Dang 《Engineering》 SCIE EI CAS CSCD 2023年第8期254-265,共12页
Although numerous advances have been made in information technology in the past decades,there is still a lack of progress in information systems dynamics(ISD),owing to the lack of a mathematical foundation needed to d... Although numerous advances have been made in information technology in the past decades,there is still a lack of progress in information systems dynamics(ISD),owing to the lack of a mathematical foundation needed to describe information and the lack of an analytical framework to evaluate information systems.The value of ISD lies in its ability to guide the design,development,application,and evaluation of largescale information system-of-systems(So Ss),just as mechanical dynamics theories guide mechanical systems engineering.This paper reports on a breakthrough in these fundamental challenges by proposing a framework for information space,improving a mathematical theory for information measurement,and proposing a dynamic configuration model for information systems.In this way,it establishes a basic theoretical framework for ISD.The proposed theoretical methodologies have been successfully applied and verified in the Smart Court So Ss Engineering Project of China and have achieved significant improvements in the quality and efficiency of Chinese court informatization.The proposed ISD provides an innovative paradigm for the analysis,design,development,and evaluation of large-scale complex information systems,such as electronic government and smart cities. 展开更多
关键词 System-of-systems engineering Information theory Information measurement Information systems dynamics Judicial informatization
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储液式CCS耦合P2G的综合能源系统低碳经济调度
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作者 李欣 李涵文 +3 位作者 陈德秋 李新宇 鲁玲 郭攀锋 《电力系统及其自动化学报》 CSCD 北大核心 2024年第5期105-113,共9页
为应对电转气P2G(power-to-gas)和碳捕集系统CCS(carbon capture system)在可再生能源出力不足时耦合失效的问题,考虑对常规CCS引入CO_(2)储液罐以加强P2G和CCS的耦合。首先,构建储液式CCS和P2G的耦合模型,利用储液罐将CCS捕集的CO_(2)... 为应对电转气P2G(power-to-gas)和碳捕集系统CCS(carbon capture system)在可再生能源出力不足时耦合失效的问题,考虑对常规CCS引入CO_(2)储液罐以加强P2G和CCS的耦合。首先,构建储液式CCS和P2G的耦合模型,利用储液罐将CCS捕集的CO_(2)时移至可再生能源富足时段,供P2G再利用;其次,构建储液式CCS与P2G耦合的电热气综合能源系统日前优化调度模型;最后,以北方某工业园区为例进行仿真。结果证明所提模型可以充分利用CCS捕集的CO_(2),从而获得更好的经济和环境效益。 展开更多
关键词 电热气综合能源系统 储液式碳捕集系统 电转气 低碳经济调度
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ISO25000-Related Metrics for Evaluating the Quality of Complex Information Systems
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作者 Antonia Stefani Bill Vassiliadis 《Journal of Computer and Communications》 2023年第9期18-43,共26页
Evaluating complex information systems necessitates deep contextual knowledge of technology, user needs, and quality. The quality evaluation challenges increase with the system’s complexity, especially when multiple ... Evaluating complex information systems necessitates deep contextual knowledge of technology, user needs, and quality. The quality evaluation challenges increase with the system’s complexity, especially when multiple services supported by varied technological modules, are offered. Existing standards for software quality, such as the ISO25000 series, provide a broad framework for evaluation. Broadness offers initial implementation ease albeit, it often lacks specificity to cater to individual system modules. This paper maps 48 data metrics and 175 software metrics on specific system modules while aligning them with ISO standard quality traits. Using the ISO25000 series as a foundation, especially ISO25010 and 25012, this research seeks to augment the applicability of these standards to multi-faceted systems, exemplified by five distinct software modules prevalent in modern information ecosystems. 展开更多
关键词 Software Quality Information systems Quality Standards Quality Metrics ISO25000
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基于HFACS模型的军事演训活动风险评估指标体系构建
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作者 欧朝敏 张志华 +2 位作者 刘燕 姜江 刘润普 《国防科技》 2024年第2期97-107,142,共12页
基于人因分析与分类系统(HFACS)分析军事演训活动的全面风险,考虑联合军事演训和新域新质作战力量的特点,并突出演训活动的战斗力标准。在改进HFACS模型分析框架的基础上,逐层次细化拆解,建立初步的风险评估指标库,并结合专家知识运用... 基于人因分析与分类系统(HFACS)分析军事演训活动的全面风险,考虑联合军事演训和新域新质作战力量的特点,并突出演训活动的战斗力标准。在改进HFACS模型分析框架的基础上,逐层次细化拆解,建立初步的风险评估指标库,并结合专家知识运用风险矩阵对指标库进行优化。构建人为因素视角下涵盖战斗力的风险、组织管理的风险、不安全行为的前提条件的风险和不安全行为的风险等4个方面以及包含战斗精神、新型主战武器、智能装备等在内的15项极高风险指标、20项高风险指标和8项中风险指标的风险评估指标体系。 展开更多
关键词 军事演训活动 风险评估 指标体系 人因分析与分类系统
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Propagation Characteristics of Ultrasonic Guided Waves in Grouted Rockbolt Systems with Bond Defects under Different Confining Conditions
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作者 Shuisheng Yu Jin Chen +2 位作者 Yawei Wang Honghao Yang Shucan Lu 《Journal of Modern Physics》 CAS 2023年第5期722-740,共19页
A rockbolt acting in the rock mass is subjected to the combined action of the pull-out load and confining pressure, and the bond quality of the rockbolt directly affects the stability of the roadway and cavern. Theref... A rockbolt acting in the rock mass is subjected to the combined action of the pull-out load and confining pressure, and the bond quality of the rockbolt directly affects the stability of the roadway and cavern. Therefore, in this study, confining pressure and pull-out load are applied to grouted rockbolt systems with bond defects by a numerical simulation method, and the rockbolt is detected by ultrasonic guided waves to study the propagation law of ultrasonic guided waves in defective rockbolt systems and the bond quality of rockbolts under the combined action of pull-out load and confining pressure. The numerical simulation results show that the length and location of bond defects can be detected by ultrasonic guided waves under the combined action of pull-out load and confining pressure. Under no pull-out load, with increasing confining pressure, the low-frequency part of the guided wave frequency in the rockbolt increases, the high-frequency part decreases, the weakening effect of the confining pressure on the guided wave propagation law increases, and the bond quality of the rockbolt increases. The existence of defects cannot change the strengthening effect of the confining pressure on the guided wave propagation law under the same pull-out load or the weakening effect of the pull-out load on the guided wave propagation law under the same confining pressure. 展开更多
关键词 Grouted Rockbolt systems Bond Defect Pull-Out Load Confining Pressure Ultrasonic Guided Wave
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两种高氮化合物对CS混合燃烧剂性能的影响
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作者 严霄 刘勇 +2 位作者 景黄丽 吴莹 侯帅 《火工品》 CAS CSCD 北大核心 2024年第3期60-64,共5页
为提高燃烧型CS催泪弹的性能,通过在CS混合燃烧剂中添加不同含量的新型高氮含能材料5,5’-偶氮四唑铵盐(AZT)和5,5’-联四唑铵盐(BTA)制备了改性混合燃烧剂。采用气相色谱法测定改性混合燃烧剂的CS气化率,通过DSC测试改性混合燃烧剂的... 为提高燃烧型CS催泪弹的性能,通过在CS混合燃烧剂中添加不同含量的新型高氮含能材料5,5’-偶氮四唑铵盐(AZT)和5,5’-联四唑铵盐(BTA)制备了改性混合燃烧剂。采用气相色谱法测定改性混合燃烧剂的CS气化率,通过DSC测试改性混合燃烧剂的相容性,并测试其撞击感度、摩擦感度。结果表明:一定添加量的AZT和BTA能够提高CS气化率;AZT与CS混合燃烧剂相容,BTA与CS混合燃烧剂不相容;在撞击感度和摩擦感度测试条件下AZT改性混合燃烧剂均不发火。研究表明AZT可用作CS混合燃烧剂的添加剂组分。 展开更多
关键词 催泪弹 高氮化合物 cs混合燃烧剂 气化率 性能
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BC/CS复合水凝胶的3D打印工艺研究
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作者 杨晓宇 张治国 李全胜 《传感器与微系统》 CSCD 北大核心 2024年第2期52-56,共5页
以细菌纤维素(BC)和壳聚糖(CS)为基质的水凝胶同时具有细菌纤维素的高生物相容性和壳聚糖的抗菌性能,在伤口敷料、组织工程等领域获得了广泛的应用,但其3D打印仍面临困难。本文利用BC和CS的物理特性和其交联机制,制备出可用于3D打印的BC... 以细菌纤维素(BC)和壳聚糖(CS)为基质的水凝胶同时具有细菌纤维素的高生物相容性和壳聚糖的抗菌性能,在伤口敷料、组织工程等领域获得了广泛的应用,但其3D打印仍面临困难。本文利用BC和CS的物理特性和其交联机制,制备出可用于3D打印的BC/CS复合水凝胶油墨,同时使用纳米粘土作为流变改性剂,提升水凝胶的自支撑能力。对于交联方法,不再采用传统的浸泡方式,使用喷雾器将戊二醛溶液均匀喷洒在打印样品表面,既不会破坏样品的结构,也可以达到交联的目的。接着,构建了一种适合BC/CS复合水凝胶打印的3D打印系统,并在此基础上研究分析了喷头挤出压力、移动速度、打印高度对水凝胶精度的影响。本文提出的方法有望实现BC/CS复合水凝胶的墨水直写(DIW)打印提供指导。 展开更多
关键词 细菌纤维素 壳聚糖 3D打印 墨水直写 自支撑
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多模态视域下高职课程思政4Cs融合式教学研究——以外贸专业课程为例
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作者 陈丹丹 《邢台职业技术学院学报》 2024年第1期26-30,共5页
高职外贸专业既有语言类专业的人文性、思想性特点、又兼具商贸类专业的社会性、实践性特点。从教学模式的中观层面和教学设计的微观层面展开研究,以课程思政为引领,基于高职教育“以就业为导向”的类型属性,结合外贸类专业的学科特点,... 高职外贸专业既有语言类专业的人文性、思想性特点、又兼具商贸类专业的社会性、实践性特点。从教学模式的中观层面和教学设计的微观层面展开研究,以课程思政为引领,基于高职教育“以就业为导向”的类型属性,结合外贸类专业的学科特点,以4Cs为理论依据,以多模态教学内容为载体构建高职外贸专业融合式教学模式,并探讨多模态教学对学生知识技能发展和思政育人成果的三重影响,对高职课程思政建设有积极促进作用。 展开更多
关键词 4cs教学原则框架 多模态 课程思政 高职 外贸专业
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