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50份加工型辣椒DH系苗期耐低温弱光综合评价
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作者 王春萍 李怡斐 +5 位作者 张世才 杨小苗 段敏杰 雷开荣 黄启中 黄任中 《中国蔬菜》 北大核心 2024年第6期48-54,共7页
以前期利用花药培养技术创制的50份加工型辣椒DH系为试验材料,以SPAD值、F_(v)/F_(m)、根系直径、茎叶干质量、根系干质量、整株干质量和根冠比7个指标的耐低温弱光指数为评价指标,采用模糊隶属函数和聚类分析法对其进行耐低温弱光综合... 以前期利用花药培养技术创制的50份加工型辣椒DH系为试验材料,以SPAD值、F_(v)/F_(m)、根系直径、茎叶干质量、根系干质量、整株干质量和根冠比7个指标的耐低温弱光指数为评价指标,采用模糊隶属函数和聚类分析法对其进行耐低温弱光综合评价。结果表明:50份DH系的耐低温弱光模糊隶属函数综合指数范围在0.20~0.76之间,聚类分析可将其分为两大类,根据耐低温弱光指数特点和模糊隶属函数综合指数可确定第Ⅱ类有7份DH系为耐低温弱光材料,即H201605-8、H201604-4-1、H201612-4-1、H201605-7、H201612-4、H201605-34和H201604-18。50份加工型辣椒DH系间耐低温弱光性差异较大,可作为相关机理研究的试验材料;筛选出的7份耐低温弱光DH系为培育适合设施栽培的优良辣椒新品种提供了材料基础,也为定向培育抗非生物逆境辣椒种质新材料提供了参考。 展开更多
关键词 辣椒 dh 低温弱光 模糊隶属函数分析 聚类分析
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DHSEGATs:distance and hop-wise structures encoding enhanced graph attention networks 被引量:1
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作者 HUANG Zhiguo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第2期350-359,共10页
Numerous works prove that existing neighbor-averaging graph neural networks(GNNs)cannot efficiently catch structure features,and many works show that injecting structure,distance,position,or spatial features can signi... Numerous works prove that existing neighbor-averaging graph neural networks(GNNs)cannot efficiently catch structure features,and many works show that injecting structure,distance,position,or spatial features can significantly improve the performance of GNNs,however,injecting high-level structure and distance into GNNs is an intuitive but untouched idea.This work sheds light on this issue and proposes a scheme to enhance graph attention networks(GATs)by encoding distance and hop-wise structure statistics.Firstly,the hop-wise structure and distributional distance information are extracted based on several hop-wise ego-nets of every target node.Secondly,the derived structure information,distance information,and intrinsic features are encoded into the same vector space and then added together to get initial embedding vectors.Thirdly,the derived embedding vectors are fed into GATs,such as GAT and adaptive graph diffusion network(AGDN)to get the soft labels.Fourthly,the soft labels are fed into correct and smooth(C&S)to conduct label propagation and get final predictions.Experiments show that the distance and hop-wise structures encoding enhanced graph attention networks(DHSEGATs)achieve a competitive result. 展开更多
关键词 graph attention network(GAT) graph structure information label propagation
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利用小孢子培养技术创制红菜薹早熟DH系
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作者 赵丽芬 邓英 +2 位作者 付文苑 王青青 杨巍 《种子》 北大核心 2024年第1期137-145,共9页
为获得早熟型的双单倍体(DH)植株,加快早熟型红菜薹育种进程,本研究以15个早熟型红菜薹品种为试材,进行小孢子培养,观察小孢子发育过程并对再生植株进行倍性鉴定。结果表明,当花瓣/花药(P/A)长度比值为0.6~0.8时,红菜薹小孢子72%~78%处... 为获得早熟型的双单倍体(DH)植株,加快早熟型红菜薹育种进程,本研究以15个早熟型红菜薹品种为试材,进行小孢子培养,观察小孢子发育过程并对再生植株进行倍性鉴定。结果表明,当花瓣/花药(P/A)长度比值为0.6~0.8时,红菜薹小孢子72%~78%处于单核靠边期;共有6个基因型红菜薹出胚,其中出胚率最大的为gy21-55,平均出胚率为14.3胚/蕾;选取子叶形胚进行植株再生,成苗率在90%以上;利用流式细胞仪对再生植株进行倍性鉴定,平均自然加倍率达76.8%。gy21-40、gy21-55表现出早熟特性,与对照植株相比获得的DH植株可分别提早5 d和8 d抽薹。 展开更多
关键词 红菜薹 游离小孢子培养 植株再生 早熟型dh
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稀土Ce对DH36船板钢显微组织及耐腐蚀性能的影响研究
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作者 祝英杰 孟祥超 +3 位作者 刘香军 杨昌桥 王婷 杨吉春 《稀有金属与硬质合金》 CAS CSCD 北大核心 2024年第3期40-47,65,共9页
针对稀土对钢耐腐蚀性的影响规律及稀土夹杂对船板钢的局部腐蚀机理的研究不足,采用金相显微镜、扫描电子显微镜、激光共聚焦显微镜、电化学工作站研究了在3.5%NaCl溶液中稀土Ce含量对DH36船板钢显微组织和耐腐蚀性能的影响。结果表明,... 针对稀土对钢耐腐蚀性的影响规律及稀土夹杂对船板钢的局部腐蚀机理的研究不足,采用金相显微镜、扫描电子显微镜、激光共聚焦显微镜、电化学工作站研究了在3.5%NaCl溶液中稀土Ce含量对DH36船板钢显微组织和耐腐蚀性能的影响。结果表明,稀土Ce可以细化试验钢的晶粒尺寸,同时降低试验钢的珠光体片层间距。稀土Ce的加入将试验钢中的MnS和Al_(2)O_(3)+MnS夹杂转变为MnS+CeAlO_(3)、Mn-Al-O-Ce、Mn-S-Al-O-Ce夹杂。相比于未添加Ce和添加0.001 0%Ce的试验钢而言,Ce含量为0.009 2%时试验钢的腐蚀速率最低,团絮状腐蚀产物最少,腐蚀坑的尺寸与数量最小,表面粗糙程度较小,且初期仍具有金属光泽;稀土Ce的加入使得试验钢的腐蚀电位升高,腐蚀电流密度降低。腐蚀时间为5 d时,Ce含量为0.009 2%时试验钢的腐蚀电流密度最低(2.225×10^(-5 )A/cm^(2)),腐蚀电压最高(-1.057 V),耐腐蚀性能最佳。 展开更多
关键词 dh36船板钢 稀土Ce 夹杂物 腐蚀形貌 耐腐蚀性能
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Cooperative Channel and Optimized Route Selection in Adhoc Network 被引量:1
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作者 D.Manohari M.S.Kavitha +1 位作者 K.Periyakaruppan B.Chellapraba 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期1547-1560,共14页
Over the last decade,mobile Adhoc networks have expanded dramati-cally in popularity,and their impact on the communication sector on a variety of levels is enormous.Its uses have expanded in lockstep with its growth.D... Over the last decade,mobile Adhoc networks have expanded dramati-cally in popularity,and their impact on the communication sector on a variety of levels is enormous.Its uses have expanded in lockstep with its growth.Due to its instability in usage and the fact that numerous nodes communicate data concur-rently,adequate channel and forwarder selection is essential.In this proposed design for a Cognitive Radio Cognitive Network(CRCN),we gain the confidence of each forwarding node by contacting one-hop and second level nodes,obtaining reports from them,and selecting the forwarder appropriately with the use of an optimization technique.At that point,we concentrate our efforts on their channel,selection,and lastly,the transmission of data packets via the designated forwarder.The simulation work is validated in this section using the MATLAB program.Additionally,steps show how the node acts as a confident forwarder and shares the channel in a compatible method to communicate,allowing for more packet bits to be transmitted by conveniently picking the channel between them.We cal-culate the confidence of the node at the start of the network by combining the reliability report for thefirst hop and the reliability report for the secondary hop.We then refer to the same node as the confident node in order to operate as a forwarder.As a result,we witness an increase in the leftover energy in the output.The percentage of data packets delivered has also increased. 展开更多
关键词 Adhoc network confident FORWARDER one-hop optimized route selection secondary report channel selection
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Ce对DH36船板钢显微组织和力学性能的影响
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作者 刘亚一 刘香军 +1 位作者 杨昌桥 杨吉春 《稀有金属与硬质合金》 CAS CSCD 北大核心 2024年第3期34-39,共6页
为探究稀土Ce对DH36船板钢显微组织和力学性能的影响,采用真空感应炉熔炼不同Ce含量的DH36船板钢,利用场发射扫描电镜、显微硬度计、冲击试验机、电子万能试验机等设备研究了Ce对DH36船板钢组织、硬度、冲击性能、拉伸性能的影响。结果... 为探究稀土Ce对DH36船板钢显微组织和力学性能的影响,采用真空感应炉熔炼不同Ce含量的DH36船板钢,利用场发射扫描电镜、显微硬度计、冲击试验机、电子万能试验机等设备研究了Ce对DH36船板钢组织、硬度、冲击性能、拉伸性能的影响。结果显示:在DH36船板钢中加入Ce使铁素体和珠光体组织细化。含0.009%Ce的试验钢综合力学性能最好,硬度增幅最大,相比未加Ce的试验钢提升15.6%;抗拉强度由未添加Ce的581.97 MPa提升到643.80 MPa,提升10.6%;冲击功由未添加Ce的162.8 J提升到174.5 J,提升7.2%。加入稀土Ce后,试验钢的拉伸断口和冲击断口形貌得到改善,韧窝数量增多,断口表面的夹杂物类型发生改变,由大尺寸不规则夹杂物变成了小尺寸类球状稀土夹杂物,降低了有害夹杂物引起的应力集中,使断口表面的裂纹源明显减少。 展开更多
关键词 dh36船板钢 稀土Ce 显微组织 力学性能 断口形貌 韧窝 夹杂物
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Pluggable multitask diffractive neural networks based on cascaded metasurfaces 被引量:1
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作者 Cong He Dan Zhao +8 位作者 Fei Fan Hongqiang Zhou Xin Li Yao Li Junjie Li Fei Dong Yin-Xiao Miao Yongtian Wang Lingling Huang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第2期23-31,共9页
Optical neural networks have significant advantages in terms of power consumption,parallelism,and high computing speed,which has intrigued extensive attention in both academic and engineering communities.It has been c... Optical neural networks have significant advantages in terms of power consumption,parallelism,and high computing speed,which has intrigued extensive attention in both academic and engineering communities.It has been considered as one of the powerful tools in promoting the fields of imaging processing and object recognition.However,the existing optical system architecture cannot be reconstructed to the realization of multi-functional artificial intelligence systems simultaneously.To push the development of this issue,we propose the pluggable diffractive neural networks(P-DNN),a general paradigm resorting to the cascaded metasurfaces,which can be applied to recognize various tasks by switching internal plug-ins.As the proof-of-principle,the recognition functions of six types of handwritten digits and six types of fashions are numerical simulated and experimental demonstrated at near-infrared regimes.Encouragingly,the proposed paradigm not only improves the flexibility of the optical neural networks but paves the new route for achieving high-speed,low-power and versatile artificial intelligence systems. 展开更多
关键词 optical neural networks diffractive deep neural networks cascaded metasurfaces
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联合应用基因分型和DH3检测406例女性子宫颈HPV感染分析与临床意义
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作者 姜朋飞 沈思环 印洪林 《临床与实验病理学杂志》 CAS 北大核心 2024年第3期325-326,共2页
HPV属于球形无包膜的双链DNA病毒,能特异性引起人体皮肤黏膜的鳞状上皮增殖,可导致多种良恶性病变。HPV高危型持续感染是导致子宫颈癌发生的主要原因,其检测方法多种、多样,各有优缺点。本科室联合应用基因分型和第三代杂交捕获技术定... HPV属于球形无包膜的双链DNA病毒,能特异性引起人体皮肤黏膜的鳞状上皮增殖,可导致多种良恶性病变。HPV高危型持续感染是导致子宫颈癌发生的主要原因,其检测方法多种、多样,各有优缺点。本科室联合应用基因分型和第三代杂交捕获技术定量分型(daltonbio hybrid capture 3,DH3),可以准确检测子宫颈中HPV型别和病毒载量的高低,对子宫颈癌的筛查进行精准分流,现作简要介绍。1材料与方法1.1材料收集2021~2022年我院妇产科门诊和健康管理中心406例女性子宫颈标本,患者年龄18~76岁,中位年龄34岁。 展开更多
关键词 子宫颈 HPV 基因分型 dh3 联合应用
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Social-ecological perspective on the suicidal behaviour factors of early adolescents in China:a network analysis 被引量:1
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作者 Yuan Li Peiying Li +5 位作者 Mengyuan Yuan Yonghan Li Xueying Zhang Juan Chen Gengfu Wang Puyu Su 《General Psychiatry》 CSCD 2024年第1期143-150,共8页
Background In early adolescence,youth are highly prone to suicidal behaviours.Identifying modifiable risk factors during this critical phase is a priority to inform effective suicide prevention strategies.Aims To expl... Background In early adolescence,youth are highly prone to suicidal behaviours.Identifying modifiable risk factors during this critical phase is a priority to inform effective suicide prevention strategies.Aims To explore the risk and protective factors of suicidal behaviours(ie,suicidal ideation,plans and attempts)in early adolescence in China using a social-ecological perspective.Methods Using data from the cross-sectional project‘Healthy and Risky Behaviours Among Middle School Students in Anhui Province,China',stratified random cluster sampling was used to select 5724 middle school students who had completed self-report questionnaires in November 2020.Network analysis was employed to examine the correlates of suicidal ideation,plans and attempts at four levels,namely individual(sex,academic performance,serious physical llness/disability,history of self-harm,depression,impulsivity,sleep problems,resilience),family(family economic status,relationship with mother,relationship with father,family violence,childhood abuse,parental mental illness),school(relationship with teachers,relationship with classmates,school-bullying victimisation and perpetration)and social(social support,satisfaction with society).Results In total,37.9%,19.0%and 5.5%of the students reported suicidal ideation,plans and attempts in the past 6 months,respectively.The estimated network revealed that suicidal ideation,plans and attempts were collectively associated with a history of self-harm,sleep problems,childhood abuse,school bullying and victimisation.Centrality analysis indicated that the most influential nodes in the network were history of self-harm and childhood abuse.Notably,the network also showed unique correlates of suicidal ideation(sex,weight=0.60;impulsivity,weight=0.24;family violence,weight=0.17;relationship with teachers,weight=-0.03;school-bullying perpetration,weight=0.22),suicidal plans(social support,weight=-0.15)and suicidal attempts(relationship with mother,weight=-0.10;parental mental llness,weight=0.61).Conclusions This study identified the correlates of suicidal ideation,plans and attempts,and provided practical implications for suicide prevention for young adolescents in China.Firstly,this study highlighted the importance of joint interventions across multiple departments.Secondly,the common risk factors of suicidal ideation,plans and attempts were elucidated.Thirdly,this study proposed target interventions to address the unique influencing factors of suicidal ideation,plans and attempts. 展开更多
关键词 network ANALYSIS PREVENTION
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Activation Redistribution Based Hybrid Asymmetric Quantization Method of Neural Networks 被引量:1
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作者 Lu Wei Zhong Ma Chaojie Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期981-1000,共20页
The demand for adopting neural networks in resource-constrained embedded devices is continuously increasing.Quantization is one of the most promising solutions to reduce computational cost and memory storage on embedd... The demand for adopting neural networks in resource-constrained embedded devices is continuously increasing.Quantization is one of the most promising solutions to reduce computational cost and memory storage on embedded devices.In order to reduce the complexity and overhead of deploying neural networks on Integeronly hardware,most current quantization methods use a symmetric quantization mapping strategy to quantize a floating-point neural network into an integer network.However,although symmetric quantization has the advantage of easier implementation,it is sub-optimal for cases where the range could be skewed and not symmetric.This often comes at the cost of lower accuracy.This paper proposed an activation redistribution-based hybrid asymmetric quantizationmethod for neural networks.The proposedmethod takes data distribution into consideration and can resolve the contradiction between the quantization accuracy and the ease of implementation,balance the trade-off between clipping range and quantization resolution,and thus improve the accuracy of the quantized neural network.The experimental results indicate that the accuracy of the proposed method is 2.02%and 5.52%higher than the traditional symmetric quantization method for classification and detection tasks,respectively.The proposed method paves the way for computationally intensive neural network models to be deployed on devices with limited computing resources.Codes will be available on https://github.com/ycjcy/Hybrid-Asymmetric-Quantization. 展开更多
关键词 QUANTIZATION neural network hybrid asymmetric ACCURACY
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双向拉伸试样测试区域尺寸对DH780屈服行为的影响
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作者 胡钊 连昌伟 +4 位作者 何睿 陈博 侯泽然 林建平 李亚 《塑性工程学报》 CAS CSCD 北大核心 2024年第8期179-188,共10页
为了探究十字双向拉伸试样测试区域尺寸对高强钢屈服行为的影响,以DH780双相钢为研究对象,参考ISO标准十字试样,开展了不同测试区域尺寸试样的双向拉伸实验对比研究;为了使小型十字试样获得的实验结果与ISO标准试样相同,通过正交实验优... 为了探究十字双向拉伸试样测试区域尺寸对高强钢屈服行为的影响,以DH780双相钢为研究对象,参考ISO标准十字试样,开展了不同测试区域尺寸试样的双向拉伸实验对比研究;为了使小型十字试样获得的实验结果与ISO标准试样相同,通过正交实验优化了十字试样的几何尺寸。结果表明,在等双拉加载条件下,随着测试区域尺寸的减小,实验获得的双轴各向异性r值基本相同。而双轴等效屈服应力先减小后增大,其核心原因是不同尺寸试样中心测试区域的变形程度不同;对于测试区域尺寸为8 mm×8 mm的小型十字试样,其主要几何参数对实验结果的影响程度排序为:狭缝数量>臂间圆角半径>狭缝长度;优化后的8 mm×8 mm新试样与ISO标准30 mm×30 mm试样的实验屈服轨迹点相对差值相较于原始试样的6.90%减小到2.36%。 展开更多
关键词 dh780钢 屈服强度 双向拉伸实验 测试区域尺寸
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Biodiversity metrics on ecological networks: Demonstrated with animal gastrointestinal microbiomes 被引量:1
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作者 Zhanshan(Sam)Ma Lianwei Li 《Zoological Research(Diversity and Conservation)》 2024年第1期51-65,共15页
Biodiversity has become a terminology familiar to virtually every citizen in modern societies.It is said that ecology studies the economy of nature,and economy studies the ecology of humans;then measuring biodiversity... Biodiversity has become a terminology familiar to virtually every citizen in modern societies.It is said that ecology studies the economy of nature,and economy studies the ecology of humans;then measuring biodiversity should be similar with measuring national wealth.Indeed,there have been many parallels between ecology and economics,actually beyond analogies.For example,arguably the second most widely used biodiversity metric,Simpson(1949)’s diversity index,is a function of familiar Gini-index in economics.One of the biggest challenges has been the high“diversity”of diversity indexes due to their excessive“speciation”-there are so many indexes,similar to each country’s sovereign currency-leaving confused diversity practitioners in dilemma.In 1973,Hill introduced the concept of“numbers equivalent”,which is based on Renyi entropy and originated in economics,but possibly due to his abstruse interpretation of the concept,his message was not widely received by ecologists until nearly four decades later.What Hill suggested was similar to link the US dollar to gold at the rate of$35 per ounce under the Bretton Woods system.The Hill numbers now are considered most appropriate biodiversity metrics system,unifying Shannon,Simpson and other diversity indexes.Here,we approach to another paradigmatic shift-measuring biodiversity on ecological networks-demonstrated with animal gastrointestinal microbiomes representing four major invertebrate classes and all six vertebrate classes.The network diversity can reveal the diversity of species interactions,which is a necessary step for understanding the spatial and temporal structures and dynamics of biodiversity across environmental gradients. 展开更多
关键词 Biodiversity on network Hill numbers Animal gut microbiome network link diversity network species diversity network abundance-weighted link diversity
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Insights into microbiota community dynamics and flavor development mechanism during golden pomfret(Trachinotus ovatus)fermentation based on single-molecule real-time sequencing and molecular networking analysis 被引量:1
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作者 Yueqi Wang Qian Chen +5 位作者 Huan Xiang Dongxiao Sun-Waterhouse Shengjun Chen Yongqiang Zhao Laihao Li Yanyan Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期101-114,共14页
Popular fermented golden pomfret(Trachinotus ovatus)is prepared via spontaneous fermentation;however,the mechanisms underlying the regulation of its flavor development remain unclear.This study shows the roles of the ... Popular fermented golden pomfret(Trachinotus ovatus)is prepared via spontaneous fermentation;however,the mechanisms underlying the regulation of its flavor development remain unclear.This study shows the roles of the complex microbiota and the dynamic changes in microbial community and flavor compounds during fish fermentation.Single-molecule real-time sequencing and molecular networking analysis revealed the correlations among different microbial genera and the relationships between microbial taxa and volatile compounds.Mechanisms underlying flavor development were also elucidated via KEGG based functional annotations.Clostridium,Shewanella,and Staphylococcus were the dominant microbial genera.Forty-nine volatile compounds were detected in the fermented fish samples,with thirteen identified as characteristic volatile compounds(ROAV>1).Volatile profiles resulted from the interactions among the microorganisms and derived enzymes,with the main metabolic pathways being amino acid biosynthesis/metabolism,carbon metabolism,and glycolysis/gluconeogenesis.This study demonstrated the approaches for distinguishing key microbiota associated with volatile compounds and monitoring the industrial production of high-quality fermented fish products. 展开更多
关键词 Fermented golden pomfret Microbiota community Volatile compound Co-occurrence network Metabolic pathway
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A data-driven model of drop size prediction based on artificial neural networks using small-scale data sets 被引量:1
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作者 Bo Wang Han Zhou +3 位作者 Shan Jing Qiang Zheng Wenjie Lan Shaowei Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期71-83,共13页
An artificial neural network(ANN)method is introduced to predict drop size in two kinds of pulsed columns with small-scale data sets.After training,the deviation between calculate and experimental results are 3.8%and ... An artificial neural network(ANN)method is introduced to predict drop size in two kinds of pulsed columns with small-scale data sets.After training,the deviation between calculate and experimental results are 3.8%and 9.3%,respectively.Through ANN model,the influence of interfacial tension and pulsation intensity on the droplet diameter has been developed.Droplet size gradually increases with the increase of interfacial tension,and decreases with the increase of pulse intensity.It can be seen that the accuracy of ANN model in predicting droplet size outside the training set range is reach the same level as the accuracy of correlation obtained based on experiments within this range.For two kinds of columns,the drop size prediction deviations of ANN model are 9.6%and 18.5%and the deviations in correlations are 11%and 15%. 展开更多
关键词 Artificial neural network Drop size Solvent extraction Pulsed column Two-phase flow HYDRODYNAMICS
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Machine Learning-Based Alarms Classification and Correlation in an SDH/WDM Optical Network to Improve Network Maintenance
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作者 Deussom Djomadji Eric Michel Takembo Ntahkie Clovis +2 位作者 Tchapga Tchito Christian Arabo Mamadou Michael Ekonde Sone 《Journal of Computer and Communications》 2023年第2期122-141,共20页
The evolution of telecommunications has allowed the development of broadband services based mainly on fiber optic backbone networks. The operation and maintenance of these optical networks is made possible by using su... The evolution of telecommunications has allowed the development of broadband services based mainly on fiber optic backbone networks. The operation and maintenance of these optical networks is made possible by using supervision platforms that generate alarms that can be archived in the form of log files. But analyzing the alarms in the log files is a laborious and difficult task for the engineers who need a degree of expertise. Identifying failures and their root cause can be time consuming and impact the quality of service, network availability and service level agreements signed between the operator and its customers. Therefore, it is more than important to study the different possibilities of alarms classification and to use machine learning algorithms for alarms correlation in order to quickly determine the root causes of problems faster. We conducted a research case study on one of the operators in Cameroon who held an optical backbone based on SDH and WDM technologies with data collected from 2016-03-28 to “2022-09-01” with 7201 rows and 18. In this paper, we will classify alarms according to different criteria and use 02 unsupervised learning algorithms namely the K-Means algorithm and the DBSCAN to establish correlations between alarms in order to identify root causes of problems and reduce the time to troubleshoot. To achieve this objective, log files were exploited in order to obtain the root causes of the alarms, and then K-Means algorithm and the DBSCAN were used firstly to evaluate their performance and their capability to identify the root cause of alarms in optical network. 展开更多
关键词 Optical network ALARMS Log Files Root Cause Analysis Machine Learning
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Design of Evolutionary Algorithm Based Energy Efficient Clustering Approach for Vehicular Adhoc Networks
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作者 VDinesh SSrinivasan +1 位作者 Gyanendra Prasad Joshi Woong Cho 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期687-699,共13页
In a vehicular ad hoc network(VANET),a massive quantity of data needs to be transmitted on a large scale in shorter time durations.At the same time,vehicles exhibit high velocity,leading to more vehicle disconnections... In a vehicular ad hoc network(VANET),a massive quantity of data needs to be transmitted on a large scale in shorter time durations.At the same time,vehicles exhibit high velocity,leading to more vehicle disconnections.Both of these characteristics result in unreliable data communication in VANET.A vehicle clustering algorithm clusters the vehicles in groups employed in VANET to enhance network scalability and connection reliability.Clustering is considered one of the possible solutions for attaining effectual interaction in VANETs.But one such difficulty was reducing the cluster number under increasing transmitting nodes.This article introduces an Evolutionary Hide Objects Game Optimization based Distance Aware Clustering(EHOGO-DAC)Scheme for VANET.The major intention of the EHOGO-DAC technique is to portion the VANET into distinct sets of clusters by grouping vehicles.In addition,the DHOGO-EAC technique is mainly based on the HOGO algorithm,which is stimulated by old games,and the searching agent tries to identify hidden objects in a given space.The DHOGO-EAC technique derives a fitness function for the clustering process,including the total number of clusters and Euclidean distance.The experimental assessment of the DHOGO-EAC technique was carried out under distinct aspects.The comparison outcome stated the enhanced outcomes of the DHOGO-EAC technique compared to recent approaches. 展开更多
关键词 Vehicular networks CLUSTERING evolutionary algorithm fitness function distance metric
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Development of a convolutional neural network based geomechanical upscaling technique for heterogeneous geological reservoir 被引量:1
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作者 Zhiwei Ma Xiaoyan Ou Bo Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2111-2125,共15页
Geomechanical assessment using coupled reservoir-geomechanical simulation is becoming increasingly important for analyzing the potential geomechanical risks in subsurface geological developments.However,a robust and e... Geomechanical assessment using coupled reservoir-geomechanical simulation is becoming increasingly important for analyzing the potential geomechanical risks in subsurface geological developments.However,a robust and efficient geomechanical upscaling technique for heterogeneous geological reservoirs is lacking to advance the applications of three-dimensional(3D)reservoir-scale geomechanical simulation considering detailed geological heterogeneities.Here,we develop convolutional neural network(CNN)proxies that reproduce the anisotropic nonlinear geomechanical response caused by lithological heterogeneity,and compute upscaled geomechanical properties from CNN proxies.The CNN proxies are trained using a large dataset of randomly generated spatially correlated sand-shale realizations as inputs and simulation results of their macroscopic geomechanical response as outputs.The trained CNN models can provide the upscaled shear strength(R^(2)>0.949),stress-strain behavior(R^(2)>0.925),and volumetric strain changes(R^(2)>0.958)that highly agree with the numerical simulation results while saving over two orders of magnitude of computational time.This is a major advantage in computing the upscaled geomechanical properties directly from geological realizations without the need to perform local numerical simulations to obtain the geomechanical response.The proposed CNN proxybased upscaling technique has the ability to(1)bridge the gap between the fine-scale geocellular models considering geological uncertainties and computationally efficient geomechanical models used to assess the geomechanical risks of large-scale subsurface development,and(2)improve the efficiency of numerical upscaling techniques that rely on local numerical simulations,leading to significantly increased computational time for uncertainty quantification using numerous geological realizations. 展开更多
关键词 Upscaling Lithological heterogeneity Convolutional neural network(CNN) Anisotropic shear strength Nonlinear stressestrain behavior
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Discontinuity development patterns and the challenges for 3D discrete fracture network modeling on complicated exposed rock surfaces 被引量:1
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作者 Wen Zhang Ming Wei +8 位作者 Ying Zhang Tengyue Li Qing Wang Chen Cao Chun Zhu Zhengwei Li Zhenbang Nie Shuonan Wang Han Yin 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2154-2171,共18页
Natural slopes usually display complicated exposed rock surfaces that are characterized by complex and substantial terrain undulation and ubiquitous undesirable phenomena such as vegetation cover and rockfalls.This st... Natural slopes usually display complicated exposed rock surfaces that are characterized by complex and substantial terrain undulation and ubiquitous undesirable phenomena such as vegetation cover and rockfalls.This study presents a systematic outcrop research of fracture pattern variations in a complicated rock slope,and the qualitative and quantitative study of the complex phenomena impact on threedimensional(3D)discrete fracture network(DFN)modeling.As the studies of the outcrop fracture pattern have been so far focused on local variations,thus,we put forward a statistical analysis of global variations.The entire outcrop is partitioned into several subzones,and the subzone-scale variability of fracture geometric properties is analyzed(including the orientation,the density,and the trace length).The results reveal significant variations in fracture characteristics(such as the concentrative degree,the average orientation,the density,and the trace length)among different subzones.Moreover,the density of fracture sets,which is approximately parallel to the slope surface,exhibits a notably higher value compared to other fracture sets across all subzones.To improve the accuracy of the DFN modeling,the effects of three common phenomena resulting from vegetation and rockfalls are qualitatively analyzed and the corresponding quantitative data processing solutions are proposed.Subsequently,the 3D fracture geometric parameters are determined for different areas of the high-steep rock slope in terms of the subzone dimensions.The results show significant variations in the same set of 3D fracture parameters across different regions with density differing by up to tenfold and mean trace length exhibiting differences of 3e4 times.The study results present precise geological structural information,improve modeling accuracy,and provide practical solutions for addressing complex outcrop issues. 展开更多
关键词 Complicated exposed rock surfaces Discontinuity characteristic variation Three-dimensional discrete fracture network modeling Outcrop study Vegetation cover and rockfalls
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Influencer identification of dynamical networks based on an information entropy dimension reduction method
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作者 段东立 纪思源 袁紫薇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期375-384,共10页
Identifying critical nodes or sets in large-scale networks is a fundamental scientific problem and one of the key research directions in the fields of data mining and network science when implementing network attacks,... Identifying critical nodes or sets in large-scale networks is a fundamental scientific problem and one of the key research directions in the fields of data mining and network science when implementing network attacks, defense, repair and control.Traditional methods usually begin from the centrality, node location or the impact on the largest connected component after node destruction, mainly based on the network structure.However, these algorithms do not consider network state changes.We applied a model that combines a random connectivity matrix and minimal low-dimensional structures to represent network connectivity.By using mean field theory and information entropy to calculate node activity,we calculated the overlap between the random parts and fixed low-dimensional parts to quantify the influence of node impact on network state changes and ranked them by importance.We applied this algorithm and the proposed importance algorithm to the overall analysis and stratified analysis of the C.elegans neural network.We observed a change in the critical entropy of the network state and by utilizing the proposed method we can calculate the nodes that indirectly affect muscle cells through neural layers. 展开更多
关键词 dynamical networks network influencer low-dimensional dynamics network disintegration
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A multilayer network diffusion-based model for reviewer recommendation
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作者 黄羿炜 徐舒琪 +1 位作者 蔡世民 吕琳媛 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期700-717,共18页
With the rapid growth of manuscript submissions,finding eligible reviewers for every submission has become a heavy task.Recommender systems are powerful tools developed in computer science and information science to d... With the rapid growth of manuscript submissions,finding eligible reviewers for every submission has become a heavy task.Recommender systems are powerful tools developed in computer science and information science to deal with this problem.However,most existing approaches resort to text mining techniques to match manuscripts with potential reviewers,which require high-quality textual information to perform well.In this paper,we propose a reviewer recommendation algorithm based on a network diffusion process on a scholar-paper multilayer network,with no requirement for textual information.The network incorporates the relationship of scholar-paper pairs,the collaboration among scholars,and the bibliographic coupling among papers.Experimental results show that our proposed algorithm outperforms other state-of-the-art recommendation methods that use graph random walk and matrix factorization and methods that use machine learning and natural language processing,with improvements of over 7.62%in recall,5.66%in hit rate,and 47.53%in ranking score.Our work sheds light on the effectiveness of multilayer network diffusion-based methods in the reviewer recommendation problem,which will help to facilitate the peer-review process and promote information retrieval research in other practical scenes. 展开更多
关键词 reviewer recommendation multilayer network network diffusion model recommender systems complex networks
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