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Tuning the phase separation in La_(0.325)Pr_(0.3)Ca_(0.375)MnO_3 using the electric double-layer field effect
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作者 崔丽敏 李洁 +5 位作者 张玉 赵璐 邓辉 黄克强 李贺康 郑东宁 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期528-534,共7页
Electric double-layer field effect experiments were performed on ultrathin films of La0.325Pr0.3Ca0.375MnO3, which is noted for its micrometer-scale phase separation. A clear change of resistance up to 220% was observ... Electric double-layer field effect experiments were performed on ultrathin films of La0.325Pr0.3Ca0.375MnO3, which is noted for its micrometer-scale phase separation. A clear change of resistance up to 220% was observed and the characteristic metal-insulator transition temperature Tp was also shifted. The changes of both the resistance and Tp, suggest that the electric field induced not only tuning of the carrier density but also rebalancing of the phase separation states. The change of the charge-ordered insulating phase fraction was estimated to be temperature dependent, and a maximum of 16% was achieved in the phase separation regime. This tuning effect was partially irreversible, which might be due to an oxygen vacancy migration that is driven by the huge applied electric field. 展开更多
关键词 electric double-layer field effect MANGANITES phase separation
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SEPARATED FLOW AROUND BENT-NOSE BICONIC IN HYPERSONIC FLOW
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作者 N.Arai S.Sakaguchi +1 位作者 Y.Wada S.Ogawa 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1991年第2期126-132,共7页
This article investigates the separated flow around the bent-nose biconic, in which the second ordered TVD(Total Variation Diminishing) method is applied. The governing cqua-tion is a thin layer Navier-Stokes equation... This article investigates the separated flow around the bent-nose biconic, in which the second ordered TVD(Total Variation Diminishing) method is applied. The governing cqua-tion is a thin layer Navier-Stokes equation. The surface pressure distribution at the leeward side is a little higher in the vicinity of the symmetrical plane. This seems to be caused by the development of the vortex at the leeward side due to the separated flow. The location of a separation line and the size are in very good agreement with the experiment. Also the secondary separation is captured very clearly. 展开更多
关键词 AOTV separated FLOW AROUND BENT-NOSE BICONIC IN HYPERSONIC FLOW LINE very
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Chemical Selectivity of Laser Ion Source for on-Line Mass Separator
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作者 Zhao, Zhizheng Yang, Yongfeng +1 位作者 Cai, Xicheng Somerville, L.P. 《Chinese journal of nuclear physics》 EI 1997年第1期48-52,共5页
Thulium(Tm)atoms are resonantly ionized in a hot tube by stepwise excitations us-ing three dye lasers pumped by a series of copper vapor pulsed at a 10 kHz rate.The chemicalselectivity of the laser ion source is measu... Thulium(Tm)atoms are resonantly ionized in a hot tube by stepwise excitations us-ing three dye lasers pumped by a series of copper vapor pulsed at a 10 kHz rate.The chemicalselectivity of the laser ion source is measured as a function of temperature of the tubes made ofTa,Nb-Zr and TaC.The chemical selectivity rises from 50 to 10000 with decreasing tube temp-erature and strongly depends on the tube material.A chemical selectivity of about 10000 withhigh efficiencies is obtained with the Nb-Zr and TaC tubes.Such a laser ion source can be usedin on-line mass separator to obtain isobarically pure ion beams. 展开更多
关键词 Laser ION SOURCE Chemical SELECTIVITY ON-LINE MASS separATOR
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Microfluidic Analytical System with On-Line Luminol Chemiluminescence Detection Based on Annular Flow of Phase Separation Multiphase Flow
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作者 Junki Manai Kei Nishiyama Kazuhiko Tsukagoshi 《Journal of Analytical Sciences, Methods and Instrumentation》 2017年第2期29-39,共11页
Microfluidic analytical system was developed based on annular flow of phase separation multiphase flow with a ternary water-hydrophilic/hydrophobic organic solvent solution. The analytical system was combined with on-... Microfluidic analytical system was developed based on annular flow of phase separation multiphase flow with a ternary water-hydrophilic/hydrophobic organic solvent solution. The analytical system was combined with on-line luminol chemiluminescence detection for catechin analysis. The water (10 mM phosphate buffer, pH 7.3)-acetonitrile-ethyl acetate mixed solution (3:8:4, volume ratio) containing 60 μM luminol and 2 mM hydrogen peroxide as a carrier was fed into the capillary tube (open-tubular fused-silica, 75 μm inner diameter, 110 cm effective length) at a flow rate of 1.0 μL·min-1. The carrier solution showed stable chemiluminescence as a baseline on the flow chart. Eight catechins were detected as negative peaks for their antioxidant potential with different detection times. The system was applied to analyze the amounts of catechin in commercially available green tea beverages. 展开更多
关键词 Microfluidic ANALYTICAL SYSTEM Phase separation Multiphase Flow CATECHIN ON-LINE LUMINOL Chemiluminescence DETECTION
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Influence of secondary lining thickness on mechanical behaviours of double-layer lining in large-diameter shield tunnels
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作者 Shimin Wang Xuhu He +3 位作者 Xiaoyu Peng Ya Wang Zhengxin Li Zihan 《Underground Space》 SCIE EI CSCD 2024年第5期130-150,共21页
In large-diameter shield tunnels,applying the double-layer lining structure can improve the load-bearing properties and maintain the stability of segmental lining.The secondary lining thickness is a key parameter in t... In large-diameter shield tunnels,applying the double-layer lining structure can improve the load-bearing properties and maintain the stability of segmental lining.The secondary lining thickness is a key parameter in the design of a double lining structure,which is worth being explored.Based on an actual large-diameter shield tunnel,loading model tests are carried out to investigate the effect of the secondary lining thickness on the mechanical behaviours of the double lining structure.The test results show that within the range of secondary lining thicknesses discussed,the load-bearing limit of the double-layer lining increases with growing secondary lining thickness.As a passive support,the secondary lining acts as an auxiliary load-bearing structure by contacting the segment.And changes in secondary lining thickness have a significant effect on the contact state between the segment and secondary lining,with both the contact pressure level and the contact area between the two varying.For double-layer lining structures in large-diameter shield tunnels,it is proposed that the stiffness of the secondary lining needs to be matched to the stiffness of the segment,as this allows them to have a coordinated deformation and a good joint load-bearing effect. 展开更多
关键词 Large-diameter shield tunnels double-layer lining structure Secondary lining thickness Stiffness matching Similar model test
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Absorption linewidth inversion with wavelength modulation spectroscopy 被引量:3
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作者 颜悦 杜振辉 +1 位作者 李金义 王瑞雪 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期368-373,共6页
For absorption linewidth inversion with wavelength modulation spectroscopy(WMS), an optimized WMS spectral line fitting method was demonstrated to infer absorption linewidth effectively, and the analytical expressio... For absorption linewidth inversion with wavelength modulation spectroscopy(WMS), an optimized WMS spectral line fitting method was demonstrated to infer absorption linewidth effectively, and the analytical expressions for relationships between Lorentzian linewidth and the separations of first harmonic peak-to-valley and second harmonic zero-crossing were deduced. The transition of CO_2 centered at 4991.25 cm^(-1) was used to verify the optimized spectral fitting method and the analytical expressions. Results showed that the optimized spectra fitting method was able to infer absorption accurately and compute more than 10 times faster than the commonly used numerical fitting procedure. The second harmonic zero-crossing separation method calculated an even 6 orders faster than the spectra fitting without losing any accuracy for Lorentzian dominated cases. Additionally, linewidth calculated through second harmonic zero-crossing was preferred for much smaller error than the first harmonic peak-to-valley separation method. The presented analytical expressions can also be used in on-line optical sensing applications, electron paramagnetic resonance, and further theoretical characterization of absorption lineshape. 展开更多
关键词 absorption linewidth wavelength modulation spectroscopy absorption spectroscopy spectral line fitting separation of harmonics
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Interaction Between Line Soliton and Algebraic Soliton for Asymmetric Nizhnik-Novikov-Veselov Equation 被引量:1
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作者 RUAN Hang-Yu LI Zhi-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1547-1552,共6页
Starting from the variable separation approach, the algebraic soliton solution and the solution describing the interaction between line soliton and algebraic soliton are obtained by selecting appropriate seed solution... Starting from the variable separation approach, the algebraic soliton solution and the solution describing the interaction between line soliton and algebraic soliton are obtained by selecting appropriate seed solution for (2+1)-dimensional ANNV equation. The behaviors of interactions are discussed in detail both analytically and graphically. It is shown that there are two kinds of singular interactions between line soliton and algebraic soliton: 1) the resonant interaction where the algebraic soliton propagates together with the line soliton and persists infinitely; 2) the extremely repulsive interaction where the algebraic soliton affects the motion of the line soliton infinitely apart. 展开更多
关键词 variable separation approach the interaction between line soliton and algebraic soliton (2+1)-dimensional ANNV equation
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Breakthrough in the China's Separation Technology for Extraction of Rare Earth Elements
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作者 HAO Ziguo FEI Hongcai +1 位作者 LIU Lian Susan TURNER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第6期1743-1744,共2页
Separation technology of rare earth elements (REEs), as the critical step in the separation process, had long been fraught with technical difficulty. A research project conducted by Baotou Shibo Rare Earth Extracti... Separation technology of rare earth elements (REEs), as the critical step in the separation process, had long been fraught with technical difficulty. A research project conducted by Baotou Shibo Rare Earth Extraction & Equipment Co. Ltd., Baotou REE Research Institute, and Baotou Steel & REE Group Hi-Tech Co. Ltd (Inner Mongolia), has successfully solved the problem using a centrifugal extractor and advanced techniques to achieve a key breakthrough. 展开更多
关键词 LINE Breakthrough in the China’s separation Technology for Extraction of Rare Earth Elements REE
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SOLID-STATE VARIABLE-TEMPERATURE NMR STUDY ON THE PHASE SEPARATION OF POLYETHER POLYURETHANE ZWITTERIONOMERS
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作者 杨光 陈群 +2 位作者 王源身 杨昌正 邬学文 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1994年第4期302-308,共7页
Polyether-polyurethane zwitterionomers based on 4, 4'-diphenylmethane diisocyanate(MDI), methyl diethanolamine (MDEA), and polytetramethylene oxide glycol (PTMO) werestudied with variable-temperature wide-line ~1H... Polyether-polyurethane zwitterionomers based on 4, 4'-diphenylmethane diisocyanate(MDI), methyl diethanolamine (MDEA), and polytetramethylene oxide glycol (PTMO) werestudied with variable-temperature wide-line ~1H NMR. It is found that upon ionization, degree ofphase separation in the polymer system decreased at first due to the loss of hard segmentregularity, while further ionization increased the degree of phase separation through increasinghard phase cohesion and difference of polarity between hard and soft segments. 展开更多
关键词 Polyether polyurethane Variable temperature Wide-line NMR Phase separation
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Generalization of Some Problems with <i>s</i>-Separation
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作者 Beih El-Sayed El-Desouky Mohamed Moustafa Gad Shimaa El-Eraqy 《Applied Mathematics》 2015年第1期1-6,共6页
In this article we apply and discuss El-Desouky technique to derive a generalization of the problem of selecting k balls from an n-line with no two adjacent balls being s-separation. We solve the problem in which the ... In this article we apply and discuss El-Desouky technique to derive a generalization of the problem of selecting k balls from an n-line with no two adjacent balls being s-separation. We solve the problem in which the separation of the adjacent elements is not having odd and even separation. Also we enumerate the number of ways of selecting k objects from n-line objects with no two adjacent being of separations m, m + 1, …, pm, where p is positive integer. Moreover we discuss some applications on these problems. 展开更多
关键词 Probability Function ss-separation s-Successions n-Line n-Circle
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The Independence-Separation Problem on the 3-D Rook’s Graph
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作者 Paul A. Burchett 《Open Journal of Discrete Mathematics》 2016年第3期167-173,共7页
Both independence and independence-separation problems on chessboard graphs have been studied in detail, with hundreds of papers in the broader independence category, and several on the independence-separation problem... Both independence and independence-separation problems on chessboard graphs have been studied in detail, with hundreds of papers in the broader independence category, and several on the independence-separation problem variant for chessboard graphs. In this paper, the inde-pendence-separation problem is considered on the d-dimensional rook’s graph. A lower bound of k, for , is found for the independence-separation number on the d-dimensional rook’s graph, denoted by . For the case where , it is found that when n is odd and , . Conjecture and discussion are added. 展开更多
关键词 CHESS Independence-separation Number Independence Number p-Dimensional Grid-Line Graphs p-Dimensional Rook’s Graph
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基于稀疏编码的复杂机械振动信号盲分离方法
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作者 王金东 王畅 +3 位作者 赵海洋 李彦阳 曹威龙 黄飞虎 《噪声与振动控制》 CSCD 北大核心 2024年第1期168-173,186,共7页
复杂机械振动信号激励源较多,故源信号之间互为相关源,且较难满足统计独立特性,导致传统盲源分离方法分离效果不佳。对此,提出一种基于信号稀疏编码的机械振动信号盲分离方法。盲源分离的关键在于对混合矩阵的精确估计,然而机械振源中... 复杂机械振动信号激励源较多,故源信号之间互为相关源,且较难满足统计独立特性,导致传统盲源分离方法分离效果不佳。对此,提出一种基于信号稀疏编码的机械振动信号盲分离方法。盲源分离的关键在于对混合矩阵的精确估计,然而机械振源中相关成分的存在严重影响混合矩阵的估计。对此,首先对观测信号进行短时傅里叶变换,增加信号稀疏性;然后利用稀疏编码筛选出具备直线聚类特性的时频观测点,利用K均值(K-means)聚类法找到聚类中心;最后利用所提筛选规则找到估计的混合矩阵,重构出源信号。通过对往复压缩机故障数据的分析,验证了所提方法有效性。 展开更多
关键词 振动与波 盲源分离 相关源 稀疏编码 直线聚类 压缩机故障信号
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同心分注井在线电动验封仪研制及应用
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作者 张福涛 《石油地质与工程》 CAS 2024年第4期101-104,111,共5页
随着油田开发的不断深入,分层注水仍是补充地层能量、实现油田稳产、提高采收率的主要开发方式,原有同心分层注水井验封技术存在仪器定位难、密封件易损坏、验封效率低等问题,采用设计和试验相结合的研究方法,研制了同心分注井在线电动... 随着油田开发的不断深入,分层注水仍是补充地层能量、实现油田稳产、提高采收率的主要开发方式,原有同心分层注水井验封技术存在仪器定位难、密封件易损坏、验封效率低等问题,采用设计和试验相结合的研究方法,研制了同心分注井在线电动验封仪,并配套测调、验封一体多功能地面控制系统,集成流量、上/下压力等多参数测试技术,实现了一次下井、多层验封测试。试验表明,验封仪的坐卡/解卡性能、胶筒坐封/解封性能、整机承压能力、密封承压能力均能达到要求,现场应用效果良好,有效解决了验封效率不高等问题,提高了分层注水测试效率和合格率,为提升油田精细注水效果提供了可靠的工艺技术。 展开更多
关键词 分注井 在线实时 电动 多层验封
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渤海某重质油田采出液短流程回注工艺侧线应用研究
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作者 王亚儒 邵琦 薛金伟 《石化技术》 CAS 2024年第6期93-96,共4页
含油废水的处理是海上油气田开采平台运行的关键环节之一。为提高经济效益和油水分离的效率,开发了高效微气浮(AMFD)除油分离器,小型组合纤维聚结(CFC)油水分离器和介质颗粒聚结过滤技术(MPE)分离器。并在中海石油渤海某海上平台进行了... 含油废水的处理是海上油气田开采平台运行的关键环节之一。为提高经济效益和油水分离的效率,开发了高效微气浮(AMFD)除油分离器,小型组合纤维聚结(CFC)油水分离器和介质颗粒聚结过滤技术(MPE)分离器。并在中海石油渤海某海上平台进行了小规模连续性工业侧线试验,验证了设备在实际工业应用环境中的油水分离性能。结果表明,相比于平台原处理流程,“AMFD+CFC+MPE”流程总停留时间减少87%,取消了破乳剂和清水剂的使用,同时减少了22%的反向破乳剂使用量,效率提高了74.14%。出水各项指标满足平台回注水标准,处理效果优于平台原流程。 展开更多
关键词 海上平台 油水分离 侧线试验 生产水除油
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加胶内衬复合钢管制造工艺探索及质量评价
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作者 杨勤祥 廖青云 《钢管》 CAS 2024年第1期60-63,共4页
通过在内衬复合钢管两层之间添加特殊黏合剂,并根据胶黏剂特性采用适当的加热温度和复合工艺提高两层之间的黏结强度的方法解决了铺管船Reel-Lay铺设方法卷曲时衬管的分离和起皱问题。试制的φ273.1 mm×(12.7+3)mm规格L450+316L内... 通过在内衬复合钢管两层之间添加特殊黏合剂,并根据胶黏剂特性采用适当的加热温度和复合工艺提高两层之间的黏结强度的方法解决了铺管船Reel-Lay铺设方法卷曲时衬管的分离和起皱问题。试制的φ273.1 mm×(12.7+3)mm规格L450+316L内衬复合钢管的黏结强度达到30 MPa以上。对试制样品进行弯曲半径R为8.19 m和9.56 m的弯曲试验评价,基、衬管没有分离和起皱。结果表明,这种两层之间加胶的工艺方法可以满足海上Reel-Lay铺设钢管的卷曲要求。 展开更多
关键词 内衬复合钢管 卷曲铺设 加胶 分离 起皱
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基于膜脱气的光声光谱系统在线实时监测变压器油中溶解气体含量的方法构建
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作者 刘启迪 吴哲 +2 位作者 施运杏 王天伟 韩毓旺 《理化检验(化学分册)》 CAS CSCD 北大核心 2024年第6期549-555,共7页
对变压器油中溶解气体含量进行快速实时监测可以有效对变压器潜在故障做出预警诊断,因此进行了题示研究。利用高透气性的Teflon-AF2400膜组件与高灵敏光声光谱检测器搭建了一套油中溶解气体在线监测系统,系统最短检测时间为2.5 min。构... 对变压器油中溶解气体含量进行快速实时监测可以有效对变压器潜在故障做出预警诊断,因此进行了题示研究。利用高透气性的Teflon-AF2400膜组件与高灵敏光声光谱检测器搭建了一套油中溶解气体在线监测系统,系统最短检测时间为2.5 min。构建了理论脱气模型并从气室体积、油温和油中常见变压器故障气体(CO、C_(2)H_(2)、C_(2)H_(4)、C_(2)H_(6)、CH_(4))体积分数角度论证了模型的准确度。模型可在20 min内实现故障气体脱气平衡体积分数的预测,缩小气室体积或升高油温,该时间还可进一步减小。当变压器油中故障气体体积分数急剧变化,20 min内所建模型所得的预测平衡体积分数和实测平衡体积分数的相对偏差小于7.0%。 展开更多
关键词 变压器油 溶解气体 油气分离膜 光声光谱 模型 在线实时监测
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脱硫胺液除油新技术的工业侧线试验
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作者 张百庆 吴红梅 《炼油与化工》 CAS 2024年第1期26-29,共4页
为解决炼油厂脱硫胺液带油、影响净化干气产品质量及下游硫磺回收装置运行等问题,某炼油厂采用AMFD自适应高效除油技术+MPE颗粒除油脱固技术+CFC组合纤维深度破乳3级分离除油技术,进行了15 d工业侧线试验。试验结果表明:通过该技术设备... 为解决炼油厂脱硫胺液带油、影响净化干气产品质量及下游硫磺回收装置运行等问题,某炼油厂采用AMFD自适应高效除油技术+MPE颗粒除油脱固技术+CFC组合纤维深度破乳3级分离除油技术,进行了15 d工业侧线试验。试验结果表明:通过该技术设备净化,胺液中油含量由3.5%降至1%,除油效果显著,提高了循环胺液的品质,保障了干气脱硫及硫磺回收装置的稳定运行,具有较高的工业化价值。 展开更多
关键词 胺液 油水分离 侧线试验
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滇中引水工程现浇仰拱全工序施工装备设计与应用
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作者 薛江松 尹建坤 陈宏明 《隧道建设(中英文)》 CSCD 北大核心 2024年第3期605-616,共12页
为实现敞开式TBM掘进与现浇仰拱同步施工,提升现浇仰拱衬砌质量,缩短工程工期,结合长大敞开式TBM水工隧洞现浇仰拱施工边界条件,研制大跨径现浇仰拱全工序施工装备。从功能要求、主桥、支腿、前后爬坡轨、行走系统、仰拱衬砌等方面对现... 为实现敞开式TBM掘进与现浇仰拱同步施工,提升现浇仰拱衬砌质量,缩短工程工期,结合长大敞开式TBM水工隧洞现浇仰拱施工边界条件,研制大跨径现浇仰拱全工序施工装备。从功能要求、主桥、支腿、前后爬坡轨、行走系统、仰拱衬砌等方面对现浇仰拱全工序施工装备开展详细设计,提出将主桥行车路面抬高,在主桥下部设置11个长度12 m功能作业区的创新思路,并在现场进行充分验证。工程实践表明:1)全工序现浇仰拱装备主桥支撑系统、行走驱动系统、模板浇筑系统使用效果初步达到设计预期;2)全工序现浇仰拱装备组装效率高、整体移动便捷、与现场施工工序契合度高、人员作业空间大,劳动强度低,施工进度最高可达到240 m/月,有效提升了TBM施工现浇仰拱技术的发展水平;3)全工序施工装备作为水工隧洞全新的工装,开创了新的施工工艺。但是该装备使本来狭窄的隧道显得更为拥挤,掘进施工交通流量受限,导致浇筑混凝土、钢筋、轨排的运输与TBM掘进物料运输之间的矛盾逐步显现,保障施工通道和TBM掘进有效进度匹配性的问题有待进一步研究。 展开更多
关键词 水工隧洞 敞开式TBM 现浇仰拱 全工序同步作业 步进式行走 分离式衬砌
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基于线谱特征保持的单枚浮标多目标信号分离算法
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作者 李大卫 吴明辉 +2 位作者 单志超 宋广明 蔡召鹏 《系统工程与电子技术》 EI CSCD 北大核心 2024年第6期1892-1898,共7页
针对单枚被动全向声纳浮标多目标信号的分离问题,提出联合非负矩阵分解(non-negative matrix factorization,NMF)和快速独立成分分析(fast independent component analysis,FastICA)的多目标信号盲分离算法。首先,基于空间与谱间相关性... 针对单枚被动全向声纳浮标多目标信号的分离问题,提出联合非负矩阵分解(non-negative matrix factorization,NMF)和快速独立成分分析(fast independent component analysis,FastICA)的多目标信号盲分离算法。首先,基于空间与谱间相关性优化NMF算法,以增强NMF算法对水声信号调制线谱特征的适应性,提高对线谱的保持优势;然后,以NMF基矩阵优势结合FastICA算法实现水声多目标信号的盲分离。仿真信号实验结果表明,所提算法取得了较高的信号分离精度,可以较好地保持信号的调制特征,同时对分离信号进行了一定的降噪增强,更好地保证了后续目标识别的特征支撑。 展开更多
关键词 被动全向声纳浮标 多目标信号盲分离 非负矩阵分解 快速独立成分分析 线谱特征保持
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分相分段法在台区线损治理中的应用
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作者 王泓力 《集成电路应用》 2024年第4期404-405,共2页
阐述分相分段法在低压台区线损治理中的优势,分析分相分段法在低压台区线损治理中的应用,包括调整供电量行为、确保综合线损统计考核与电量调整相结合、及时处理未计算线路的台区状况。
关键词 分相分段法 台区线损 电量调整
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