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Green and mild synthesis of Ca-MOF/COF functionalized silica microspheres in an acid-base tunable deep eutectic solvent for multi-mode chromatography
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作者 Yuanfei Liu Wanjiao Wei +5 位作者 Xu Liu Rui Hua Yanjuan Liu Yuefei Zhang Wei Chen Sheng Tang 《Chinese Chemical Letters》 2026年第1期547-551,共5页
Metal organic framework(MOF) assembled with coordination bonds has the disadvantage of poor stability that limits its application in the field of stationary phase,while covalent organic framework(COF)assembled through... Metal organic framework(MOF) assembled with coordination bonds has the disadvantage of poor stability that limits its application in the field of stationary phase,while covalent organic framework(COF)assembled through covalent bonds exhibits excellent structural stability.It has been shown that the stationary phases prepared by combining MOF and COF can make up for the poor stability of MOF@SiO_(2),and the MOF/COF composites have superior chromatographic separation performance.However,the traditional methods for preparing COF/MOF based stationary phases are generally solvent thermal synthesis.In this study,a green and low-cost synthesis method was proposed for the preparation of MOF/COF@SiO_(2) stationary phase.Firstly,COF@SiO_(2) was prepared in a choline chloride/ethylene glycol based deep eutectic solvent(DES).Secondly,another acid-base tunable DES prepared by mixing p-toluenesulfonic acid(PTSA)and 2-methylimidazole in different proportions was introduced as the reaction solvent and reactant for rapid synthesis of MOF/COF@SiO_(2).Compared with the toxic transition metal-based MOFs selected in most previous studies,a lightweight and non-toxic S-zone metal(calcium) based MOF was employed in this study.PTSA and calcium will form the calcium/oxygen-containing organic acid framework in acidic DES,which assembles with terephthalic acid dissolved in basic DES to form MOF.The strong hydrogen bonding effect of DES can facilitate rapid assembly of Ca-MOF.The obtained Ca-MOF/COF@SiO_(2) can be used for multi-mode chromatography to efficiently separate multiple isomeric/hydrophilic/hydrophobic analytes.The synthesis method of Ca-MOF/COF@SiO_(2) is green and mild,especially the use of acid-base tunable DES promotes the rapid synthesis of non-toxic Ca-MOF/COF@silica composites,which offers an innovative approach of greenly synthesizing novel MOF/COF stationary phases and extends their applications in the field of chromatography. 展开更多
关键词 Metal organic framework Covalent organic framework Deep eutectic solvent Silica composites multi-mode chromatography
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Multi-mode luminescence anti-counterfeiting and visual iron(Ⅲ)ions RTP detection constructed by assembly of CDs&Eu3+in porous RHO zeolite
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作者 Siyu Zong Xiaowei Yu +2 位作者 Yining Yang Xin Yang Jiyang Li 《Chinese Chemical Letters》 2025年第6期567-572,共6页
Carbon dots(CDs)-based composites have shown impressive performance in fields of information encryption and sensing,however,a great challenge is to simultaneously implement multi-mode luminescence and room-temperature... Carbon dots(CDs)-based composites have shown impressive performance in fields of information encryption and sensing,however,a great challenge is to simultaneously implement multi-mode luminescence and room-temperature phosphorescence(RTP)detection in single system due to the formidable synthesis.Herein,a multifunctional composite of Eu&CDs@p RHO has been designed by co-assembly strategy and prepared via a facile calcination and impregnation treatment.Eu&CDs@p RHO exhibits intense fluorescence(FL)and RTP coming from two individual luminous centers,Eu3+in the free pores and CDs in the interrupted structure of RHO zeolite.Unique four-mode color outputs including pink(Eu^(3+),ex.254 nm),light violet(CDs,ex.365 nm),blue(CDs,254 nm off),and green(CDs,365 nm off)could be realized,on the basis of it,a preliminary application of advanced information encoding has been demonstrated.Given the free pores of matrix and stable RTP in water of confined CDs,a visual RTP detection of Fe^(3+)ions is achieved with the detection limit as low as 9.8μmol/L.This work has opened up a new perspective for the strategic amalgamation of luminous vips with porous zeolite to construct the advanced functional materials. 展开更多
关键词 Carbon dots ZEOLITE Host-vip assembly multi-mode luminescence Phosphorescence detection Information encryption
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Strength through unity:Alkaline phosphatase-responsive AIEgen nanoprobe for aggregation-enhanced multi-mode imaging and photothermal therapy of metastatic prostate cancer
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作者 Ze Wang Hao Liang +7 位作者 Annan Liu Xingchen Li Lin Guan Lei Li Liang He Andrew K.Whittaker Bai Yang Quan Lin 《Chinese Chemical Letters》 2025年第2期261-268,共8页
Prostate cancer(PCa)is characterized by high incidence and propensity for easy metastasis,presenting significant challenges in clinical diagnosis and treatment.Tumor microenvironment(TME)-responsive nanomaterials prov... Prostate cancer(PCa)is characterized by high incidence and propensity for easy metastasis,presenting significant challenges in clinical diagnosis and treatment.Tumor microenvironment(TME)-responsive nanomaterials provide a promising prospect for imaging-guided precision therapy.Considering that tumor-derived alkaline phosphatase(ALP)is over-expressed in metastatic PCa,it makes a great chance to develop a theranostics system with ALP responsive in the TME.Herein,an ALP-responsive aggregationinduced emission luminogens(AIEgens)nanoprobe AMNF self-assembly was designed for enhancing the diagnosis and treatment of metastatic PCa.The nanoprobe exhibited self-aggregation in the presence of ALP resulted in aggregation-induced fluorescence,and enhanced accumulation and prolonged retention period at the tumor site.In terms of detection,the fluorescence(FL)/computed tomography(CT)/magnetic resonance(MR)multi-mode imaging effect of nanoprobe was significantly improved post-aggregation,enabling precise diagnosis through the amalgamation of multiple imaging modes.Enhanced CT/MR imaging can achieve assist preoperative tumor diagnosis,and enhanced FL imaging technology can achieve“intraoperative visual navigation”,showing its potential application value in clinical tumor detection and surgical guidance.In terms of treatment,AMNF showed strong absorption in the near infrared region after aggregation,which improved the photothermal treatment effect.Overall,our work developed an effective aggregation-enhanced theranostic strategy for ALP-related cancers. 展开更多
关键词 AIE Prostate cancer ALP responsive Enhanced multi-mode imaging Enhanced photothermal therapy
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Learning-Based Delay Sensitive and Reliable Traffic Adaptation for DC-PLC and 5G Integrated Multi-Mode Heterogeneous Networks
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作者 Tian Gexing Wang Ruiqiuyu +6 位作者 Pan Chao Zhou Zhenyu Yang Junzhong Zhao Chenkai Chen Bei Yang Sen Shahid Mumtaz 《China Communications》 2025年第4期65-80,共16页
Low-carbon smart parks achieve selfbalanced carbon emission and absorption through the cooperative scheduling of direct current(DC)-based distributed photovoltaic,energy storage units,and loads.Direct current power li... Low-carbon smart parks achieve selfbalanced carbon emission and absorption through the cooperative scheduling of direct current(DC)-based distributed photovoltaic,energy storage units,and loads.Direct current power line communication(DC-PLC)enables real-time data transmission on DC power lines.With traffic adaptation,DC-PLC can be integrated with other complementary media such as 5G to reduce transmission delay and improve reliability.However,traffic adaptation for DC-PLC and 5G integration still faces the challenges such as coupling between traffic admission control and traffic partition,dimensionality curse,and the ignorance of extreme event occurrence.To address these challenges,we propose a deep reinforcement learning(DRL)-based delay sensitive and reliable traffic adaptation algorithm(DSRTA)to minimize the total queuing delay under the constraints of traffic admission control,queuing delay,and extreme events occurrence probability.DSRTA jointly optimizes traffic admission control and traffic partition,and enables learning-based intelligent traffic adaptation.The long-term constraints are incorporated into both state and bound of drift-pluspenalty to achieve delay awareness and enforce reliability guarantee.Simulation results show that DSRTA has lower queuing delay and more reliable quality of service(QoS)guarantee than other state-of-the-art algorithms. 展开更多
关键词 DC-PLC and 5G integration multi-mode heterogeneous networks traffic adaptation traffic admission control traffic partition
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Multi-mode acceleration optimization control for adaptive cycle engine based on variable geometry components
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作者 Yifan WANG Haoying CHEN +1 位作者 Xuankai LIU Haibo ZHANG 《Chinese Journal of Aeronautics》 2025年第9期3-25,共23页
The acceleration and mode transition performance are two significant performances of Adaptive Cycle Engine(ACE).However,separating the processes of acceleration and mode transition will slow down the response speed of... The acceleration and mode transition performance are two significant performances of Adaptive Cycle Engine(ACE).However,separating the processes of acceleration and mode transition will slow down the response speed of thrust.Therefore,this paper proposes a multi-mode acceleration optimization control method that simultaneously performs ACE acceleration and mode transition.Firstly,an ACE component model with inlet flow characteristics was established,and the performance before and after mode transition were analyzed.Secondly,the principle of ACE acceleration optimization was analyzed,and the Front Variable Area Bypass Injector(FVABI)and Mode Selection Valve(MSV)were adopted in the acceleration process.Finally,based on the Sequential Quadratic Programming(SQP)algorithm,considering the degradation effects of engine components,we optimize the acceleration control plan for fuel and variable geometry mechanisms.The simulation results show that at the subsonic cruise point,the ACE multi-mode acceleration optimization control method can shorten the acceleration time from idle to middle state by 30.33%,and accelerate the thrust response speed by 33.72%.When the compressor flow rate of ACE deteriorates by 2% and the high-pressure turbine efficiency deteriorates by 4%,the adaptive acceleration control plan increases the high-pressure speed by 2.13% and thrust by about 6.82%;within the flight envelope,the acceleration time is reduced by more than 25%,and the thrust response speed is increased by more than 20%. 展开更多
关键词 Adaptive cycle engine Mode transition Multivariate acceleration plan Sequential quadratic planning Variable geometry components
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Electrospun Nanofibrous Transition Metal-based Bifunctional Electrocatalysts Toward Overall Water Splitting
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作者 YIN Yongting LU Xiaofeng 《高等学校化学学报》 北大核心 2026年第1期87-107,共21页
Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen e... Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen evolution reaction(HER)and the anodic oxygen evolution reaction(OER).Transition metal-based catalysts have garnered significant research interest as promising alternatives to noble-metal catalysts,owing to their low cost,tunable composition,and noble-metal-like catalytic activity.Nevertheless,systematic reviews on their application as bifunctional catalysts for overall water splitting(OWS)are still limited.This review comprehensively outlines the principal categories of bifunctional transition metal electrocatalysts derived from electrospun nanofibers(NFs),including metals,oxides,phosphides,sulfides,and carbides.Key strategies for enhancing their catalytic performance are systematically summarized,such as heterointerface engineering,heteroatom doping,metal-nonmetal-metal bridging architectures,and single-atom site design.Finally,current challenges and future research directions are discussed,aiming to provide insightful perspectives for the rational design of high-performance electrocatalysts for OWS. 展开更多
关键词 Electrospinning Nanofibers transition metal-based catalyst Overall water splitting Performance optimization
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Anomalous Hall effect and Lifshitz transition in Fe_(3)Sn_(2)nanosheets
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作者 Xue Yang Jijian Liu +14 位作者 Xinyi Zheng Lei Xu Lihong Hu Sicheng Zhou Siyuan Zhou Ximing Zhang Bingbing Tong Jie Shen Zhaozheng Lyu Xiunian Jing Fanming Qu Peiling Li Jiadong Zhou Guangtong Liu Li Lü 《Chinese Physics B》 2026年第1期287-293,共7页
Fe_(3)Sn_(2),a ferromagnetic metal with a kagome lattice,serves as an ideal platform for exploring topological electronic states and Berry curvature due to its unique band structure.However,systematic reports on the t... Fe_(3)Sn_(2),a ferromagnetic metal with a kagome lattice,serves as an ideal platform for exploring topological electronic states and Berry curvature due to its unique band structure.However,systematic reports on the transport properties of Fe_(3)Sn_(2)nanosheets remain scarce.We present temperature-dependent transport property measurements of Fe_(3)Sn_(2)nanosheets synthesized via chemical vapor deposition on Si/SiO_(2)substrates.The samples exhibit a robust anomalous Hall effect from 40 K to 300 K,along with a magnetoresistance sign reversal at 40 K at high magnetic fields,indicating a spin reorientation from in-plane to out-of-plane.Notably,a sharp crossover in the dominant transport contribution from electrons to holes near 200 K is observed,accompanied by distinct anomalous Hall behaviors in the two regimes,indicating a temperature-induced Lifshitz transition within the multi-band system.This divergence is potentially linked to a topological reconstruction of the Fermi surface across the transition.Our findings highlight the tunability of topological transport in two-dimensional kagome magnets and provide new insights into the interplay between band topology,dimensionality and magnetic order. 展开更多
关键词 kagome materials anomalous Hall effect FERROMAGNETISM Lifshitz transition
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Tracking a High-Tech Transition--How technology is powering Guangdong’s manufacturing transformation
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作者 HU FAN 《ChinAfrica》 2026年第1期30-32,共3页
The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them w... The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them was not a typical exhibition hall,but a building shaped like a gleaming stainless-steel cooking pot. 展开更多
关键词 othello kitchenware museum TECHNOLOGY industrial strength high tech transition guangdong manufacturing transformation
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Paeonol suppresses epithelial-mesenchymal transitiondriven posterior capsular opacification through activation of AMPK signaling
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作者 Qing Wang Qing-Yu Li +6 位作者 Jing Yang Jun Ma Ji-Hua Ping Zheng Wang Dai-Jie Wang Xia Hua Xiao-Yong Yuan 《International Journal of Ophthalmology(English edition)》 2026年第2期219-229,共11页
AIM:To determine whether paeonol(Pae),a naturally occurring phenolic compound,can serve as an effective pharmacological inhibitor of posterior capsular opacification(PCO).METHODS:A rat model of cataract surgery—induc... AIM:To determine whether paeonol(Pae),a naturally occurring phenolic compound,can serve as an effective pharmacological inhibitor of posterior capsular opacification(PCO).METHODS:A rat model of cataract surgery—induced PCO was established,and Pae was administered via anterior chamber injection to evaluate its preventive effect on capsular opacification and fibrotic remodeling.Histological and immunohistochemical analyses were performed to assess epithelial-mesenchymal transition(EMT)—related changes in lens epithelial cells(LECs).Ex vivo lens capsule cultures were employed to examine the expression of Vimentin and Zonula Occludens-1(ZO-1)by immunofluorescence and immunohistochemistry.In the human LEC line SRA01/04,EMT marker expression at both mRNA and protein levels was analyzed following transforming growth factor beta 2(TGF-β2)stimulation,with Pae treatment.Western blotting and immunofluorescence were used to investigate the effect of Pae on TGF-β/Smad signaling and AMP-activated protein kinase(AMPK)activation.Molecular docking was performed to predict Pae–AMPK binding,and rescue experiments with AMPK inhibition were conducted to validate the mechanistic pathway.RESULTS:Pae significantly reduced capsular opacification and fibrotic remodeling in the rat PCO model compared with controls.In LECs,Pae markedly suppressed TGF-β2–induced EMT,evidenced by decreased expression of mesenchymal markers,such as Vimentin,Fibronectin,Collagen 1A1,α-SMA and preserved epithelial junctional protein ZO-1.Mechanistically,Pae was predicted to directly interact with the catalytic pocket of AMPK,which was experimentally confirmed by enhanced AMPK phosphorylation and nuclear translocation(P<0.05).This activation disrupted canonical TGF-β/Smad signaling,leading to suppression of EMT.Rescue experiments using AMPK inhibition abrogated the anti-EMT effect of Pae,further validating the AMPK-dependent mechanism.CONCLUSION:Pae exerts a potent inhibitory effect on PCO formation by blocking EMT of LECs through direct activation of AMPK and subsequent disruption of TGF-β/Smad signaling. 展开更多
关键词 posterior capsular opacification PAEONOL epithelial-mesenchymal transition AMP-activated protein kinase transforming growth factor beta
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How Does Urban Public Transit Accessibility Affect Housing Prices?A Comprehensive Analysis with Geographical Detector Combined and Geographically Weighted Regression
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作者 TANG Jingjing HAN Huiran +3 位作者 YANG Chengfeng XU Lingyi GENG Hui LI Lei 《Chinese Geographical Science》 2026年第1期127-143,共17页
The accessibility of urban public transit directly influences residents’quality of life,travel behavior,and social equity.Its correlation with housing prices has garnered significant attention across disciplines such... The accessibility of urban public transit directly influences residents’quality of life,travel behavior,and social equity.Its correlation with housing prices has garnered significant attention across disciplines such as geography,economics,and urban planning.Although much existing research focuses on the impact of individual transportation facilities on housing prices,there is a notable gap in comprehensive analyses that assess the influence of overall urban transit accessibility on housing market dynamics.This study selected the main urban area of Hefei,China,as a case to investigate the spatial distribution of housing prices and evaluate public transit accessibility in 2022.Employing techniques such as the optimized parameter geographical detector and local spatial regression models,the study aimed to elucidate the effects and underlying mechanisms of urban transit accessibility on housing prices.The findings revealed that:1)housing prices in Hefei exhibited a clustered spatial pattern,with high prices concentrated in the city center and lower prices in peripheral areas,forming three distinct high-price hotspots with a‘belt-like’distribution;2)public transit accessibility showed a‘coreperiphery’structure,with accessibility declining in a‘circumferential’pattern around the city center.Based on the‘housing price-accessibility’dimension,four categories were identified:high price-high accessibility(37.25%),high price-low accessibility(19.07%),low price-high accessibility(21.95%),and low price-low accessibility(21.73%);3)the impact of transit accessibility on housing prices was spatially heterogeneous,with bus travel showing the strongest explanatory power(0.692),followed by automobile,subway,and bicycle travel.The interaction of these transportation modes generated a synergistic effect on housing price differentiation,with most influencing factors contributing more than 25%.These findings offer valuable insights for optimizing the spatial distribution of public transit infrastructure and improving both urban housing quality and residents’living standards. 展开更多
关键词 public transit accessibility housing prices geographically weighted regression geographical detector Hefei City China
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Structural phase transition and quasi-layered active-ion distribution suppress concentration quenching in Tb^(3+)-activated KBi(MoO_(4))_(2)
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作者 Mengyu Zhang Shujing Pan +4 位作者 Haitang Hu Wenzhi Su Yong Zou Shoujun Ding Qingli Zhang 《Chinese Physics B》 2026年第1期295-304,共10页
Conventional Tb^(3+)-doped phosphors typically suffer from concentration quenching once the doping level exceeds a critical threshold.Consequently,the development of Tb^(3+)phosphors with intrinsic resistance to conce... Conventional Tb^(3+)-doped phosphors typically suffer from concentration quenching once the doping level exceeds a critical threshold.Consequently,the development of Tb^(3+)phosphors with intrinsic resistance to concentration quenching has become a key research focus.In this work,we successfully synthesized KBi(MoO_(4))_(2):x Tb^(3+)(x=0-100 at%)(denoted as KBM:x Tb^(3+))phosphors via a high-temperature solid-state reaction.Remarkably,no concentration quenching was observed across the entire doping range.This anti-quenching behavior originates from the large Tb^(3+)-Tb^(3+)interionic distance(>5Å)inherent to the quasi-layered crystal structure,which effectively suppresses multipole-interaction-mediated energy migration.At full Tb^(3+)substitution(x=100 at%),the material undergoes a structural phase transition from the monoclinic KBM phase to the triclinicα-KTb(MoO_(4))_(2)(α-KTM)phase.Theα-KTM phosphor exhibits excellent thermal stability(activation energy=0.6129 eV)and a single-exponential decay profile,whereas KBM:x Tb^(3+)(x<100%)display double-exponential decay behaviors,attributed to dual energy transfer pathways.These findings provide new insights into the luminescence mechanisms of high-concentration rare-earth-doped systems and offer guidance for designing nextgeneration anti-quenching phosphors. 展开更多
关键词 Tb^(3+)doping layered crystal structure anti-concentration quenching structural phase transition
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Time varying congestion pricing for multi-class and multi-mode transportation system with asymmetric cost functions
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作者 钟绍鹏 邓卫 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期77-82,共6页
This paper considers the problem of time varying congestion pricing to determine optimal time-varying tolls at peak periods for a queuing network with the interactions between buses and private cars.Through the combin... This paper considers the problem of time varying congestion pricing to determine optimal time-varying tolls at peak periods for a queuing network with the interactions between buses and private cars.Through the combined applications of the space-time expanded network(STEN) and the conventional network equilibrium modeling techniques,a multi-class,multi-mode and multi-criteria traffic network equilibrium model is developed.Travelers of different classes have distinctive value of times(VOTs),and travelers from the same class perceive their travel disutility or generalized costs on a route according to different weights of travel time and travel costs.Moreover,the symmetric cost function model is extended to deal with the interactions between buses and private cars.It is found that there exists a uniform(anonymous) link toll pattern which can drive a multi-class,multi-mode and multi-criteria user equilibrium flow pattern to a system optimum when the system's objective function is measured in terms of money.It is also found that the marginal cost pricing models with a symmetric travel cost function do not reflect the interactions between traffic flows of different road sections,and the obtained congestion pricing toll is smaller than the real value. 展开更多
关键词 time varying congestion pricing ASYMMETRIC MULTI-CLASS multi-mode MULTI-CRITERIA
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大学英语的Multi-Mode教学模式
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作者 郑洁雯 《中国科教创新导刊》 2007年第27期224-224,226,共2页
针对目前高职院校大学英语教学普遍存在的问题,结合全国性大学英语教学需要改革的迫切要求,笔者对所在院校研究并应用的Multi-Mode教学模式进行分析说明,其关键性在于培养学生自主学习的积极性,较好地落实教学任务,提高学生参加英语等... 针对目前高职院校大学英语教学普遍存在的问题,结合全国性大学英语教学需要改革的迫切要求,笔者对所在院校研究并应用的Multi-Mode教学模式进行分析说明,其关键性在于培养学生自主学习的积极性,较好地落实教学任务,提高学生参加英语等级考试的通过率。 展开更多
关键词 multi-mode教学模式 编串故事 多媒体教学 写作
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Multi-mode diagnosis of a gas turbine engine using an adaptive neuro-fuzzy system 被引量:9
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作者 Houman HANACHI Jie LIU Christopher MECHEFSKE 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第1期1-9,共9页
Gas Turbine Engines (GTEs) are vastly used for generation of mechanical power in a wide range of applications from airplane propulsion systems to stationary power plants. The gaspath components of a GTE are exposed ... Gas Turbine Engines (GTEs) are vastly used for generation of mechanical power in a wide range of applications from airplane propulsion systems to stationary power plants. The gaspath components of a GTE are exposed to harsh operating and ambient conditions, leading to several degradation mechanisms. Because GTE components are mostly inaccessible for direct measure- ments and their degradation levels must be inferred from the measurements of accessible parameters, it is a challenge to acquire reliable information on the degradation conditions of the parts in different fault modes. In this work, a data-driven fault detection and degradation estima- tion scheme is developed for GTE diagnostics based on an Adaptive Neuro-Fuzzy Inference System (ANFIS). To verify the performance and accuracy of the developed diagnostic framework on GTE data, an ensemble of measurable gas path parameters has been generated by a high-fidelity GTE model under (a) diverse ambient conditions and control settings, (b) every possible combination of degradation symptoms, and (c) a broad range of signal to noise ratios. The results prove the competency of the developed framework in fault diagnostics and reveal the sensitivity of diagnostic results to measurement noise for different degradation symptoms. 展开更多
关键词 Fault detection multi-mode diagnosis Measurement noise Real-time diagnosis
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Signal classification method based on data mining formulti-mode radar 被引量:10
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作者 qiang guo pulong nan jian wan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第5期1010-1017,共8页
For the multi-mode radar working in the modern electronicbattlefield, different working states of one single radar areprone to being classified as multiple emitters when adoptingtraditional classification methods to p... For the multi-mode radar working in the modern electronicbattlefield, different working states of one single radar areprone to being classified as multiple emitters when adoptingtraditional classification methods to process intercepted signals,which has a negative effect on signal classification. A classificationmethod based on spatial data mining is presented to address theabove challenge. Inspired by the idea of spatial data mining, theclassification method applies nuclear field to depicting the distributioninformation of pulse samples in feature space, and digs out thehidden cluster information by analyzing distribution characteristics.In addition, a membership-degree criterion to quantify the correlationamong all classes is established, which ensures classificationaccuracy of signal samples. Numerical experiments show that thepresented method can effectively prevent different working statesof multi-mode emitter from being classified as several emitters,and achieve higher classification accuracy. 展开更多
关键词 multi-mode radar signal classification data mining nuclear field cloud model membership.
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3D FEM simulation of responses of LWD multi-mode resistivity imaging sonde 被引量:5
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作者 Kang Zheng-Ming Ke Shi-Zhen +3 位作者 Li Xin Mi Jin-Tai Ni Wei-Ning Li Ming-Yu 《Applied Geophysics》 SCIE CSCD 2018年第3期401-412,共12页
A new multi-mode resistivity imaging sonde, with toroidal coils as source, can conduct three resistivity measurements: azimuthal resistivity, lateral resistivity, and bit resistivity measurements. Thus, the logging ti... A new multi-mode resistivity imaging sonde, with toroidal coils as source, can conduct three resistivity measurements: azimuthal resistivity, lateral resistivity, and bit resistivity measurements. Thus, the logging time and cost are greatly saved. The toroidal coils are simplified as an extended voltage dipole and the response equations are derived for a homogenous formation. Based on 3D FEM, the depth of investigation(DOI), vertical resolution, circumferential azimuthal capacity, borehole diameter, mud resistivity, thickness of target formation, and the resistivity of the surrounding formation and mud invasion are simulated. The results suggest that the three measurement modes of the new sonde are different in vertical resolutions and DOIs. The circumferential detection ability of the azimuth button depends on the contrast between the anomaly and formation resistivity and the open angle of the anomaly. Whether the borehole is truncated at the bit or not has a great influence on the simulation results. The borehole and mud invasion affect the apparent resistivity in all modes, but the effects of resistivity of surrounding formation and thickness of the target formation are only corrected for lateral resistivity measurement. 展开更多
关键词 3D FEM LWD multi-mode RESISTIVITY imaging detection characteristics ENVIRONMENTAL effects
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Multi-mode process monitoring based on a novel weighted local standardization strategy and support vector data description 被引量:9
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作者 赵付洲 宋冰 侍洪波 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第11期2896-2905,共10页
There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because the... There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because their presumptions are that sampled-data should obey the single Gaussian distribution or non-Gaussian distribution. In order to solve these problems, a novel weighted local standardization(WLS) strategy is proposed to standardize the multimodal data, which can eliminate the multi-mode characteristics of the collected data, and normalize them into unimodal data distribution. After detailed analysis of the raised data preprocessing strategy, a new algorithm using WLS strategy with support vector data description(SVDD) is put forward to apply for multi-mode monitoring process. Unlike the strategy of building multiple local models, the developed method only contains a model without the prior knowledge of multi-mode process. To demonstrate the proposed method's validity, it is applied to a numerical example and a Tennessee Eastman(TE) process. Finally, the simulation results show that the WLS strategy is very effective to standardize multimodal data, and the WLS-SVDD monitoring method has great advantages over the traditional SVDD and PCA combined with a local standardization strategy(LNS-PCA) in multi-mode process monitoring. 展开更多
关键词 multiple operating modes weighted local standardization support vector data description multi-mode monitoring
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A Multi-mode Electronic Load Sensing Control Scheme with Power Limitation and Pressure Cut-off for Mobile Machinery 被引量:2
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作者 Min Cheng Bolin Sun +1 位作者 Ruqi Ding Bing Xu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第1期157-170,共14页
In mobile machinery,hydro-mechanical pumps are increasingly replaced by electronically controlled pumps to improve the automation level,but diversified control functions(e.g.,power limitation and pressure cut-off)are ... In mobile machinery,hydro-mechanical pumps are increasingly replaced by electronically controlled pumps to improve the automation level,but diversified control functions(e.g.,power limitation and pressure cut-off)are integrated into the electronic controller only from the pump level,leading to the potential instability of the overall system.To solve this problem,a multi-mode electrohydraulic load sensing(MELS)control scheme is proposed especially considering the switching stability from the system level,which includes four working modes of flow control,load sensing,power limitation,and pressure control.Depending on the actual working requirements,the switching rules for the different modes and the switching direction(i.e.,the modes can be switched bilaterally or unilaterally)are defined.The priority of different modes is also defined,from high to low:pressure control,power limitation,load sensing,and flow control.When multiple switching rules are satisfied at the same time,the system switches to the control mode with the highest priority.In addition,the switching stability between flow control and pressure control modes is analyzed,and the controller parameters that guarantee the switching stability are obtained.A comparative study is carried out based on a test rig with a 2-ton hydraulic excavator.The results show that the MELS controller can achieve the control functions of proper flow supplement,power limitation,and pressure cut-off,which has good stability performance when switching between different control modes.This research proposes the MELS control method that realizes the stability of multi-mode switching of the hydraulic system of mobile machinery under different working conditions. 展开更多
关键词 Hydraulic control Load sensing multi-mode Power limitation Mobile machinery
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Digital Communication Using Multi-mode Chaotic Lasers 被引量:2
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作者 WULiang ZHUShi-Qun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第2期225-230,共6页
The digital communication in a system of two multi-mode solid state chaotic lasers is investigated theoretically. If the usual method working well in a single-mode laser system is applied to a multi-mode laser system,... The digital communication in a system of two multi-mode solid state chaotic lasers is investigated theoretically. If the usual method working well in a single-mode laser system is applied to a multi-mode laser system, the memory effect of the two nearest digits can cause high rate of mistakes when the digits are decoded through the subtraction of receiver output from the transmittal. By introducing the deviations of two nearest maximum and minimum fluctuationsof the signal to decode the digit, the message can be decoded correctly. Also, this communication method does not critically depend on the quality of the chaotic synchronization of the two multi-mode lasers. 展开更多
关键词 digital communication multi-mode lasers chaotic synchronization
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Adaptive Learning-Based Delay-Sensitive and Secure Edge-End Collaboration for Multi-Mode Low-Carbon Power IoT 被引量:3
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作者 Haijun Liao Zehan Jia +6 位作者 Ruiqiuyu Wang Zhenyu Zhou Fei Wang Dongsheng Han Guangyuan Xu Zhenti Wang Yan Qin 《China Communications》 SCIE CSCD 2022年第7期324-336,共13页
Multi-mode power internet of things(PIoT)combines various communication media to provide spatio-temporal coverage for low-carbon operation in smart park.Edge-end collaboration is feasible to achieve the full utilizati... Multi-mode power internet of things(PIoT)combines various communication media to provide spatio-temporal coverage for low-carbon operation in smart park.Edge-end collaboration is feasible to achieve the full utilization of heterogeneous resources and anti-eavesdropping.However,edge-end collaboration-based multi-mode PIoT faces challenges of mutual contradiction in communication and security quality of service(QoS)guarantee,inadaptability of resource management,and multi-mode access conflict.We propose an Adaptive learning based delAysensitive and seCure Edge-End Collaboration algorithm(ACE_(2))to optimize multi-mode channel selection and split device power into artificial noise(AN)transmission and data transmission for secure data delivery.ACE_(2) can achieve multi-attribute QoS guarantee,adaptive resource management and security enhancement,and access conflict elimination with the combined power of deep actor-critic(DAC),“win or learn fast(WoLF)”mechanism,and edge-end collaboration.Simulations demonstrate its superior performance in queuing delay,energy consumption,secrecy capacity,and adaptability to differentiated low-carbon services. 展开更多
关键词 multi-mode low-carbon PIoT edge-end collaboration multi-attribute QoS guarantee security enhancement adaptive deep actor-critic
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