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Comprehensive status evaluation and prediction of blast furnace based on cascade system and combined model
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作者 Zhen Zhang Jue Tang +3 位作者 Quan Shi Mansheng Chu Mingyu Wang Zhifeng Zhang 《International Journal of Minerals,Metallurgy and Materials》 2025年第12期2942-2957,共16页
The comprehensive status of blast furnaces was one of the most important factors affecting their economy,quality,and longev-ity.The blast furnace comprehensive status had the nature of“black box,”and it was“unpredi... The comprehensive status of blast furnaces was one of the most important factors affecting their economy,quality,and longev-ity.The blast furnace comprehensive status had the nature of“black box,”and it was“unpredictable.”In this study,a blast furnace com-prehensive status score and prediction method based on a cascade system and a combined model were proposed to address this issue.A dual cascade evaluation system was developed by integrating subjective and objective weighting methods.The analytic hierarchy process,coefficient of variation,entropy weight method,and impart combinatorial games were jointly employed to determine the optimal weight distribution across indicators.Categorized statuses(raw material,gas flow,furnace body,furnace cylinder,and iron-slag)were evaluated.Based on the five categories of the status data,the second cascade was applied to upgrade the quantitative evaluation of the comprehens-ive status.The weights of the different categories were 0.22,0.15,0.22,0.21,and 0.20,respectively.According to the data analysis,the results of the comprehensive status score closely matched the on-site production logs.Based on the blast furnace smelting period,the maximal information coefficient method was applied to the 100 parameters that were most relevant to the comprehensive status.A com-bined prediction model for a comprehensive status score was designed using bidirectional long short-term memory(BiLSTM)and categorical boosting(CatBoost).The test results indicated that the combined model reduced the mean absolute error by an average of 0.275 and increased the hit rate by an average of 5.65 percentage points compared to BiLSTM or CatBoost alone.When the er-ror range was±2.5,the combined model predicted a hit rate of 91.66%for the next hour’s comprehensive status score,and its high accur-acy was deemed satisfactory for the field.SHapley Additive exPlanations(SHAP)and regression fitting were applied to analyze the lin-ear quantitative relationship between the key variables and the comprehensive status score.When the furnace bottom center temperature was increased by 10℃,the comprehensive status score increased by 0.44.This method contributes to a more precise management and control of the comprehensive status of the blast furnace on-site. 展开更多
关键词 blast furnace comprehensive status machine learning cascade evaluation system combined prediction model
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Conjugated microporous polymers-scaffolded enzyme cascade systems with enhanced catalytic activity 被引量:1
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作者 Zhenhua Wu Jiafu Shi +6 位作者 Boyu Zhang Yushuai Jiao Xiangxuan Meng Ziyi Chu Yu Chen Yiran Cheng Zhongyi Jiang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期213-223,共11页
Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs... Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs)are constructed through co-entrapping glucose oxidase(GOx)and horseradish peroxidase(HRP),in which hydrogen peroxide(H_(2)O_(2)) is the intermediate product.The interplay of low-resistance mass transfer pathway and appropriate pore wall-H_(2)O_(2) interactions facilitates the directed transfer of H_(2)O_(2),resulting in 2.4-fold and 5.0-fold elevation in catalytic activ-ity compared to free ECSs and separated ECSs,respectively.The substrate channeling effect could be regulated by altering the mass ratio of GOx to HRP.Besides,I-ECSs demonstrate excellent stabili-ties in harsh environments and multiple recycling. 展开更多
关键词 BIOCATALYSIS IMMOBILIZATION Enzyme cascade system Substrate channeling effect Conjugated microporous polymers
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DISOPE distributed model predictive control of cascade systems with network communication 被引量:1
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作者 Yan ZHANG Shaoyuan LI 《控制理论与应用(英文版)》 EI 2005年第2期131-138,共8页
A novel distributed model predictive control scheme based on dynamic integrated system optimization and parameter estimation (DISOPE) was proposed for nonlinear cascade systems under network environment. Under the d... A novel distributed model predictive control scheme based on dynamic integrated system optimization and parameter estimation (DISOPE) was proposed for nonlinear cascade systems under network environment. Under the distributed control structure, online optimization of the cascade system was composed of several cascaded agents that can cooperate and exchange information via network communication. By iterating on modified distributed linear optimal control problems on the basis of estimating parameters at every iteration the correct optimal control action of the nonlinear model predictive control problem of the cascade system could be obtained, assuming that the algorithm was convergent. This approach avoids solving the complex nonlinear optimization problem and significantly reduces the computational burden. The simulation results of the fossil fuel power unit are illustrated to verify the effectiveness and practicability of the proposed algorithm. 展开更多
关键词 cascade systems Dynamic integrated system optimization and parameter estimation (DISOPE) Model predictive control (MPC) Distributed control system (DCS) Autonomous agents Fossil fuel power unit (FFPU)
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Thermodynamics-guided two-way interlocking DNA cascade system for universal multiplexed mutation detection
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作者 Wei Zhang Liquan Liu +6 位作者 Yangwei Liao Wan Shu Xiaofeng Tang Kejun Dong Zhihao Ming Xianjin Xiao Hongbo Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第1期334-338,共5页
Detection of point mutations in driver genes is of great significance for the early diagnosis,treatment,and prognostic evaluation of cancer.However,current detection methods do not offer versatility,specificity,and ra... Detection of point mutations in driver genes is of great significance for the early diagnosis,treatment,and prognostic evaluation of cancer.However,current detection methods do not offer versatility,specificity,and rapid performance simultaneously.Thus,multiple mutation detection processes are necessary,which results in long processing times and high costs.In this study,we developed a thermodynamics-guided two-way interlocking DNA cascade system for universal multiplexed mutation detection(TTI-CS).This strategy is based on the DNA probe,which changes the thermodynamic balance of the DNA cascade by the designed bubble structure,thereby achieving a good distinction between mutant and wild-type DNA.The designed method greatly shortens the detection time through two-way intrusion.In addition,this method only changes two inexpensive trigger and bridge sequences,which replace the specific and expensive nucleic acid probes used in analyses based on traditional DNA probe methods,thereby enabling multiple detections.We performed the detection of synthetic single-stranded DNA for the five mutation points and successfully detected in endometrial cancer specimens.The detection limit of this method is0.1%,which better meets the needs of clinical low-abundance multiple mutation detection.Overall,TTI-CS is currently one of the best methods for detecting multiple mutation detections. 展开更多
关键词 Nucleic acid probes DNA cascade system UNIVERSALITY Low-abundance Multiple mutation detection
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Cascade Tank Water Quality Management: A Case Study in Thirappane Tank Cascade System, Sri Lanka
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作者 N.S.Abeysingha S.P.Dissanayake +1 位作者 S.Sumanaweera S.S.K.De Silva 《Journal of Environmental & Earth Sciences》 2021年第1期59-70,共12页
Tank cascade system(TCS)is a series of tanks located in a meso-catchment and has been accepted as a Globally Important Agricultural Heritage System found in Sri Lanka.Ecosystem components of the TCS play a major role ... Tank cascade system(TCS)is a series of tanks located in a meso-catchment and has been accepted as a Globally Important Agricultural Heritage System found in Sri Lanka.Ecosystem components of the TCS play a major role in purifying water within the system.This study attempted to investigate the water quality status and the farmers’willingness to rehabilitate the ecosystem components of the Thirappane TCS.Drinking and irrigation water quality parameters were tested in 34 locations and drinking and irrigation water quality indexes were calculated.Participatory rural appraisal and a questioner survey were conducted to gather social data.Water of TCS was observed to be appropriate for irrigation but not for drinking during the Maha cropping season.Based on the results of the Nitrate(as NO_(3)^(-))and Total Phosphate(as PO_(4)^(3-)),water of TCS can be categorized as eutrophic.Presence of ecosystem features of tank cascade system,annual income of the respondents,satisfaction on the quality of water for drinking,and the awareness about the tank cascade system significantly influenced the participatory decisions of the community on the rehabilitation of TCS.This study shall be an example and an eye opener to formulate sustainable tank cascade management plan. 展开更多
关键词 Drinking water quality Irrigation water quality Social survey Tank cascade system Watershed management
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Reliability Analysis of a Redundant Cascade System by Using Markovian Approach
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作者 Nalabolu Swathi Tallapureddy Sumathi Uma Maheswari 《Journal of Applied Mathematics and Physics》 2015年第7期911-920,共10页
In the present work, it is assumed that the n-components are arranged in the hierarchial order. The n-cascade system surviving with loss of m components by k number of attacks is studied;the general equation for the r... In the present work, it is assumed that the n-components are arranged in the hierarchial order. The n-cascade system surviving with loss of m components by k number of attacks is studied;the general equation for the reliability is obtained for the above said system;and the system reliability is computed numerically for 6-cascade system for 2-number of attacks. 展开更多
关键词 cascade system REDUNDANCY Reliability MARKOV Process k ATTACKS
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Transient Voltage Characteristics and Support Strategy of Hybrid Cascaded HVDC System Under Sending-end AC System Fault
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作者 Jiangshan Liu Fengting Li +4 位作者 Chunya Yin Lu Han Gaohang Zhang Ruikang Chen Wan Liu 《Protection and Control of Modern Power Systems》 2026年第1期53-67,共15页
During sending-end faults in the hybrid cascaded HVDC(HC-HVDC)system,the transient voltage drop characteristics under the interaction of the AC/DC hybrid system remain unclear,and the reactive power support provided b... During sending-end faults in the hybrid cascaded HVDC(HC-HVDC)system,the transient voltage drop characteristics under the interaction of the AC/DC hybrid system remain unclear,and the reactive power support provided by the HC-HVDC to the sending-end AC system requires further investigation.To address this problem,the reactive power interaction coupling mechanism between the sending-end AC system and the HC-HVDC is revealed,and the transient voltage mathematical model considering fault severity and duration is established.Under the dynamic change of the AC system voltage,the difference between the reactive power provided only by the reactive power compensation devices and by the combined modular multilevel converters(MMC)and reactive power compensation devices is analyzed.It is concluded that using MMC to provide a proportion of reactive power enhances the reactive power support to the AC system during faults.Then,the transient voltage model considering the reactive power support of MMC is established,and the critical reactive power consumption of line commutated converter(LCC)is quantified.It is concluded that the reactive power consumption of LCC exceeding its critical value deteriorates the transient voltage.A coordinated support strategy for the sending-end AC system based on reactive power support of MMC and reactive power regulation of LCC is proposed.It can effectively address the challenge of weakened reactive power support to the AC system due to voltage drop,thereby preventing the unbalanced reactive power from deteriorating the transient voltage,and realizing active support of the tran-sient voltage.Finally,a simulation model is established on the PSCAD/EMTDC platform,and the simulation results validate the effectiveness of the proposed strategy in supporting the transient voltage,under different fault types,durations,severities,and locations. 展开更多
关键词 Hybrid cascaded HVDC transient voltage cooperative control reactive power
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A novel thermophilicα-glucan phosphorylase enables molecular weight-tunable amylose biosynthesis from cellobiose via a dual-enzyme cascade system
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作者 Wei Gao Ru Yang +2 位作者 Mengli Li Ming Miao Tao Zhang 《Food Bioscience》 2025年第11期2306-2318,共13页
Non-food cellulose bioconversion to amylose offers a promising avenue for sustainable biomanufacturing while maximizing non-food biomass utilization.Nevertheless,currentα-glucan phosphorylases(αGPs)exhibit insuffici... Non-food cellulose bioconversion to amylose offers a promising avenue for sustainable biomanufacturing while maximizing non-food biomass utilization.Nevertheless,currentα-glucan phosphorylases(αGPs)exhibit insufficient thermostability and suboptimal catalytic performance,thereby limiting their feasibility for industrial implementation.In this study,a novel thermostableαGP from Dictyoglomus sp.NZ13-RE01(DspαGP)was identified and characterized through computational genome mining.The specific enzyme activity of DspαGP was 36.3±2.1 U/mg under the optimal conditions of temperature 70℃and pH 5.0.The enzyme thermal melting temperature(T_(m))was 82.26℃,and the residual activity retained 55.5%after stored at 70℃for 12 h.These results demonstrated the enzyme an exceptional catalytic efficiency and remarkable thermal stability.Kinetic analysis revealed superior substrate specificity toward maltotriose and maltotetraose with kcat/Km values of 1.96 and 1.83 mM^(-1)s^(-1),respectively.Integration of DspαGP with Clostridium thermocellum cellobiose phosphorylase established a dual-enzyme cascade system capable of synthesizing amylose with tunable molecular weight(7392-16,632 g/mol)by adjusting the cellobiose/G4 ratio,a conversion efficiency of 35.67%was achieved,significantly surpassing existing systems.Site-directed mutagenesis combined with molecular docking revealed that conserved residues Gly32,Arg364,Lys370,Tyr432,and Lys464 play critical roles in substrate binding and catalytic processes.This study provides enhanced process efficiency and operational stability for sustainable carbohydrate bioconversion applications and promoting valorization of non-edible cellulose resources. 展开更多
关键词 α-Glucan phosphorylase Thermostable enzymes Enzymatic cascade Amylose biosynthesis Tunable molecular weight
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Laponite cascade assembly activated reversible multicolor luminescence supramolecular hydrogel with near-infrared emission
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作者 Rong Zhang Yong Chen +1 位作者 Zhiyi Yu Yu Liu 《Chinese Chemical Letters》 2026年第1期306-313,共8页
Photo-responsive supramolecular assembly especially supramolecular hydrogels with tunable luminescence show a promising application potential in writable information recording and display materials.Herein,we report ph... Photo-responsive supramolecular assembly especially supramolecular hydrogels with tunable luminescence show a promising application potential in writable information recording and display materials.Herein,we report photo-responsive reversible multicolor supramolecular hydrogel with near-infrared emission,which is constructed by cucurbit[7]uril(CB[7]),cyanostilbene derivative(DAC)and Laponite XLG(LP)via supramolecular cascade assembly.Compared with the free vip molecule DAC,the confinement of macrocycle CB[7]achieve effective near-infrared fluorescence in the aqueous phase from scratch,and the subsequent cascade assembly with LP further restrict the molecular rotation of the DAC,which not only result in a substantial enhancement of the fluorescence intensity,but is also endowed with light-controlled fluorescence on/off both in the solution and hydrogel states.Further,8-hydroxy-1,3,6-pyrenetrisulfonic acid trisodium salt(HPTS)is introduced in the cascade assembly to fabricated photocontrollable reversible multicolor luminescence supramolecular hydrogel between red and green induced by Förster resonance energy transfer,which is successfully employed in reversible multiple information encryption. 展开更多
关键词 Supramolecular cascade system Multicolor luminescence Photo-responsiveness CUCURBITURIL Dynamic anti-counterfeiting
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Post-translational control of biotic stress-related nicotine biosynthesis by a MAP kinase signaling cascade 被引量:1
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作者 Yan Zhou Yongliang Liu +5 位作者 Ruiqing Lyu Sanjay Kumar Singh Xueyi Sui Xin Hou Sitakanta Pattanaik Ling Yuan 《The Crop Journal》 2026年第1期201-213,共13页
The evolutionarily conserved mitogen-activated protein kinase(MAPK)cascades relay extracellular signals into cells,triggering a variety of cellular responses.We previously revealed NtMPK4 as a positive regulator of ni... The evolutionarily conserved mitogen-activated protein kinase(MAPK)cascades relay extracellular signals into cells,triggering a variety of cellular responses.We previously revealed NtMPK4 as a positive regulator of nicotine biosynthesis;however,its upstream regulation remains unclear.Here,we characterized a MAPK cascade,comprising NtMEKK1b,NtMPKK2a,and NtMPK4,that promotes nicotine biosynthesis.This signaling module transduces external cues,including jasmonate and pathogen elicitors such as flg22,into post-translational modifications that enhance transcriptional activity and pathway gene expression.NtMPKK2a physically interacts with and phosphorylates NtMPK4 in vivo,confirming its role as an upstream kinase.RNAi-mediated silencing of NtMPKK2a significantly reduced the expression of nicotine pathway genes and decreased nicotine accumulation,whereas induced-overexpression of NtMPKK2a upregulated nicotine pathway genes and increased nicotine contents in tobacco hairy roots.Overexpression of NtMPKK2a in tobacco cells enhanced the transactivation activity of a NIC2-locus Ethylene Response Factor NtERF221 on Putrescine N-methyltransferase(NtPMT)promotor,further supporting its role in promoting nicotine biosynthesis.Furthermore,we identified NtMEKK1b,a tobacco MEKK that interacts with NtMAPKK2a in yeast cells.Knock-down of NtMEKK1b in transgenic tobacco plants attenuated the expression of nicotine pathway genes and reduced nicotine contents,whereas induced-overexpression of NtMEKK1b upregulated gene expression and nicotine accumulation.Our findings uncover a previously uncharacterized MAPK cascade module,NtMEKK1b-NtMPKK2a-NtMPK4,that regulates nicotine biosynthesis,highlighting the importance of posttranslational regulation in nicotine biosynthesis. 展开更多
关键词 Nicotine biosynthesis Specialized metabolites MAPK cascade Post-translational regulation Alkaloid biosynthesis Structural modeling
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Deterministic cascade evolution in coal and gas outbursts:From early acoustic signatures to system-wide failure
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作者 Yang Lei Zhijie Wen +2 位作者 Liang Wang Ting Ren Yujun Zuo 《International Journal of Mining Science and Technology》 2025年第6期975-987,共13页
Coal and gas outbursts constitute a critical hazard in underground mining operations,characterized by rapid transitions from localized instability to catastrophic failure.Understanding the relationship between initial... Coal and gas outbursts constitute a critical hazard in underground mining operations,characterized by rapid transitions from localized instability to catastrophic failure.Understanding the relationship between initial characteristics and final outburst scale remains a fundamental challenge in geomechanics.This study conceptualizes outbursts as deterministic cascade systems through integrated physical simulations combining high-sensitivity infrasound monitoring with energy analysis under controlled gas pressure(0.5–1.0 MPa)and confining stress(5–10 MPa)conditions.Our complementary analytical algorithms—the absolute amplitude integral and predominant period function—revealed characteristic step-wise patterns in outburst development.Quantitative analysis established a robust correlation(R2=0.91)between initial acoustic response and final outburst intensity.Energy analysis demonstrated that gas expansion dominates the outburst process(91.81%–99.09%of total energy),with desorption gas contributing 59.1%–77.7%.Time-frequency analysis showed systematic frequency migration from high(12–15 Hz)to low(4–8 Hz)bands during outburst progression,reflecting hierarchical spatial scale expansion.The concentrated energy release(>20%of total)within initial 0.2 s provides a mechanistic basis for the deterministic nature of outburst evolution.These mechanistic insights establish a quantitative framework for developing physics-based monitoring protocols and risk assessment methodologies applicable to underground coal mining operations. 展开更多
关键词 Coal and gas outburst Energy analysis cascade INFRASOUND Gas desorption
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Electronic thermal conductivity of tungsten-based systems during collision cascade processes
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作者 Jiong-Rong Wang Bi-Cai Pan 《Nuclear Science and Techniques》 2025年第5期167-176,共10页
The thermal conductivity of plasma-facing materials(PFM)exposed to intense radiation is a critical concern for the reliable usage of materials in fusion reactors.However,limited research has been performed regarding t... The thermal conductivity of plasma-facing materials(PFM)exposed to intense radiation is a critical concern for the reliable usage of materials in fusion reactors.However,limited research has been performed regarding the thermal conductivity of structures that rapidly change in a short time during collision cascade processes under irradiation.In this study,we employed the tight-binding(TB)method to investigate the electronic thermal conductivity(κ_(e))of tungsten-based systems during various cascading processes.We found thatκ_(e) values sharply decrease within the initial 0.3 picoseconds and then partially recover at a slow pace;this is closely linked to the evolution of defects and microstructural distortions.The increase in the initial kinetic energy of the primary knock-on atom and the presence of a high concentration of hydrogen atoms further decrease theκ_(e) values.Conversely,higher temperatures have a significant positive effect onκ_(e).Furthermore,the presence of a grain boundary∑5[001](130)substantially reducesκ_(e),whereas the absorption effect of point defects by the grain boundary has little influence onκ_(e) during cascades.Our findings provide a theoretical basis for evaluating changes in the thermal conductivity performance of PFMs during their usage in nuclear fusion reactors. 展开更多
关键词 Electronic thermal conductivity Collision cascade TUNGSTEN Plasma-facing materials Tight-binding calculations
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Cascade explicit tube model predictive controller:application for a multi-robot system
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作者 Ehsan Soleimani Amirhossein Nikoofard Erfan Nejabat 《Control Theory and Technology》 2025年第2期237-252,共16页
In recent years,there has been a growing demand for more efficient and robust control strategies in cooperative multi-robot systems.This paper introduces the cascade explicit tube model predictive controller(CET-MPC),... In recent years,there has been a growing demand for more efficient and robust control strategies in cooperative multi-robot systems.This paper introduces the cascade explicit tube model predictive controller(CET-MPC),a control architecture designed specifically for distributed aerial robot systems.By integrating an explicit model predictive controller(MPC)with a tube MPC,our approach significantly reduces online computational demands while enhancing robustness against disturbances such as wind and measurement noise,as well as uncertainties in inertia parameters.Further,we incorporate a cascade controller to minimize steady-state errors and improve system performance dynamically.The results of this assessment provide valuable insights into the effectiveness and reliability of the CET-MPC approach under realistic operating conditions.The simulation results of flight scenarios for multi-agent quadrotors demonstrate the controller’s stability and accurate tracking of the desired path.By addressing the complexities of quadrotors’six degrees of freedom,this controller serves as a versatile solution applicable to a wide range of multi-robot systems with varying degrees of freedom,demonstrating its adaptability and scalability beyond the quadrotor domain. 展开更多
关键词 Explicit model predictive control(MPC) Tube MPC cascade controller QUADROTOR Multi-agent system Distributed formation control
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Leader-Following Consensus for a Class of Nonlinear Cascaded Multi-Agent Systems
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作者 LI Xianda KANG Jianling 《Journal of Donghua University(English Edition)》 2025年第2期213-218,共6页
This paper focuses on the problem of leaderfollowing consensus for nonlinear cascaded multi-agent systems.The control strategies for these systems are transformed into successive control problem schemes for lower-orde... This paper focuses on the problem of leaderfollowing consensus for nonlinear cascaded multi-agent systems.The control strategies for these systems are transformed into successive control problem schemes for lower-order error subsystems.A distributed consensus analysis for the corresponding error systems is conducted by employing recursive methods and virtual controllers,accompanied by a series of Lyapunov functions devised throughout the iterative process,which solves the leaderfollowing consensus problem of a class of nonlinear cascaded multi-agent systems.Specific simulation examples illustrate the effectiveness of the proposed control algorithm. 展开更多
关键词 cascaded multi-agent system distributed control CONSENSUS recursive method
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Nickel-Catalyzed Reductive Cascade Arylalkylation of Alkenes with Cyclosulfonium Salts
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作者 Zhang Yunyi Yan Hanbing +4 位作者 Zhu Xianjin Shi Yongjia Li Junxin Yang Daoshan Li Xufeng 《有机化学》 北大核心 2026年第2期653-663,共11页
Nickel-catalyzed reductive cross-coupling(RCC)reactions between alkenes and alkyl electrophiles are undoubtedly the attractive approaches to new functionalized heterocycles.However,the alkylation reagents are still ra... Nickel-catalyzed reductive cross-coupling(RCC)reactions between alkenes and alkyl electrophiles are undoubtedly the attractive approaches to new functionalized heterocycles.However,the alkylation reagents are still rather limited for the arylalkylation of tethered alkenes via RCC reactions.Thus,developing more robust methods to access heterocycles from stable and readily available starting materials under RCC conditions is still highly challenging and desirable.A new nickelcatalyzed reductive arylalkylation of tethered alkenes with cyclosulfonium salts as C(sp^(3))electrophiles to access the sulfurcontaining oxindoles is developed.This tandem ring-opening/cyclization/reductive coupling protocol enables the efficient construction of various oxindoles bearing all-carbon quaternary centers under mild conditions with broad functional group tolerance.Notably,many drug derivatives are readily functionalized using the developed protocol. 展开更多
关键词 nickel catalysis reductive coupling ALKYLATION C—C bond cascade reaction
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Comparing of small and large optimal tapered cascades for supplying enriched uranium for fresh fuel production in the equilibrium cycle of a nuclear power reactor
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作者 S.L.Mirmohammadi J.Safdari A.A.Ghorbanpour Khamseh 《Nuclear Science and Techniques》 2026年第3期208-234,共27页
One of the main issues in designing optimum tapered cascades for uranium enrichment for annual fuel production in a power reactor is whether to employ large(fat)or small(thin)cascades.What will be the permissible and ... One of the main issues in designing optimum tapered cascades for uranium enrichment for annual fuel production in a power reactor is whether to employ large(fat)or small(thin)cascades.What will be the permissible and optimal ranges of the number of machines that can be used in a cascade?For the first time,the permissible and optimal ranges of the number of gas centrifuges that can be utilized in a cascade were investigated using two types of centrifuges,and the performance of small and large tapered cascades was discussed.The particle swarm optimization algorithm(PSO)has been used to optimize tapered cascades.The results show:(1)For the first centrifuge,41 cascades(91≤n≤4897)and for the second centrifuge,49 cascades(18≤n≤3839)with small and large sizes can be used in enrichment facilities,and the best cascade for them has 530(with 23 stages)and 39(with 7 stages)centrifuges,respectively.(2)For both centrifuges,when 600≤n(number of centrifuges=n),the large cascade performance changes are relatively insignificant.(3)For both types of gas centrifuges,the annual los s of separation power in enrichment facilities is approximately 1.25%-4.82%of the total separation work required. 展开更多
关键词 Small tapered cascade(thin) Large tapered cascade(fat) Enriched uranium fuel Power reactor PSO algorithm
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Orchestrating ion desolvation and transport via biomimetic dual-cascade separator for dendrite-free lithium metal anodes
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作者 Yuliang Gao Zihan Liu +3 位作者 Yaodong Huo Mengjing Li Shifeng Huang Tuotuo Ma 《Journal of Energy Chemistry》 2026年第3期886-894,共9页
Lithium(Li)dendrites,resulting from poor ion desolvation and transport behavior at the anode/electrolyte interface during electrodeposition,severely impede the practicality of Li metal anodes.Inspired by the transmemb... Lithium(Li)dendrites,resulting from poor ion desolvation and transport behavior at the anode/electrolyte interface during electrodeposition,severely impede the practicality of Li metal anodes.Inspired by the transmembrane cascade transport mechanism of biological ion pumps,we design a biomimetic dual-cascade separator(BDS)based on gradient pore core–shell Gd_(2)O_(3)@ZIF-7 nanoparticles to stabilize Li metal anodes.The mesoporous Gd_(2)O_(3)core,via Lewis acidic surface,weakens Li^(+) -solvent interactions,thereby reconstructing the solvation structure and achieving pre-desolvation.The microporous ZIF-7 shell then promotes final desolvation through strong confinement effect and N-rich site coordination,while its nanochannels homogenize Li^(+) transport.This synergistic meso/microporous gradient creates a unique dual-cascade effect for ion desolvation and transport.Consequently,BDS achieves a low desolvation energy barrier,a high Li^(+) transference number(0.71),and dendrite-free Li deposition.The average Coulombic efficiency rises from 72.7%to 98.4%,the cycling performance of the Li||Li symmetrical cell improves by 3.2 times,and the capacity retention of LiFePO_4(LFP)||Li full cell increases from 38.3%to73.4%after 500 cycles.This work offers a novel separator design concept,deepens Li deposition understanding,and guides separators from passive protection to active regulation. 展开更多
关键词 Lithium metal anodes DENDRITES SEPARATORS Solvation structure cascade effect
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Observation of Typhoon Trami(2024)-induced energy cascade from near-inertial waves to diurnal internal tides
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作者 Letian Chen Ze Zhang +4 位作者 Yifei Jiang Xiaojiang Zhang Jiagen Li Weimin Zhang Huizan Wang 《Atmospheric and Oceanic Science Letters》 2026年第2期74-81,共8页
Energy transfers among internal waves in the northern South China Sea are not well characterized,particularly during typhoons,owing to the lack of in situ observations.Based on high-resolution mooring data collected d... Energy transfers among internal waves in the northern South China Sea are not well characterized,particularly during typhoons,owing to the lack of in situ observations.Based on high-resolution mooring data collected during Typhoon Trami(2024),this study reveals the occurrence of robust vertical energy redistribution among diurnal internal tides(D1 ITs)and near-inertial waves(NIWs).Strikingly,the typhoon not only amplified the NIW energy but also triggered an unexpected surge in the D1 IT energy.The observed average net energy transfer rate of 1×10^(-7) W kg^(−1) from typhoon-forced NIWs to D1 ITs occurred at water depths of 120-170 m.Further bispectral analysis indicated that the energy transfer is driven by nonlinear wave—wave interaction.These results reveal the existence of a new energy transfer pathway—from atmospheric forcing to D1 ITs—and redefine the redistribution of the internal wave energy during extreme weather events. 展开更多
关键词 Tropical cyclones Mooring observation Near-inertial waves Energy cascade Diurnal internal tides South China Sea
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Visible-light induced cascade sulfonation/cyclization reaction in water towards sulfonated dihydroisoquinolino[1,2-b]quinazolinones
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作者 Jun Huang Jiangping Qin +3 位作者 Caijin Ban Jingmei Yuan Jing Yang Guoping Yang 《Chinese Chemical Letters》 2026年第2期415-418,共4页
A visible-light induced cascade sulfonation/cyclization reaction of 3-allyl-2-arylquinazolinones employing water as an environmentally friendly solvent was revealed.This transition metal-free protocol,using 9-mesityl-... A visible-light induced cascade sulfonation/cyclization reaction of 3-allyl-2-arylquinazolinones employing water as an environmentally friendly solvent was revealed.This transition metal-free protocol,using 9-mesityl-10-methylacridinium perchlorate as the photocatalyst,represents a masterly tactic for the synthesis of sulfonated dihydroisoquinolino[1,2-b]quinazolinones featuring mild conditions,facile operation,and broad substrate scope. 展开更多
关键词 Environmentally friendly solvent SULFONATION Radical cascade cyclization VISIBLE-LIGHT QUINAZOLINONE
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SMAD7 regulates the canonical Wnt signaling through TGF-β cascade crosstalk and SMAD7/β-CATENIN transcription factor complex formation during tooth regeneration
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作者 Qiuyu Chen Zhi Liu +4 位作者 Bohuai Zhou Cheng Liang Yiping Chen Weidong Tian Tian Chen 《International Journal of Oral Science》 2026年第1期103-114,共12页
Tooth morphogenesis is orchestrated by a complex interplay of signaling pathways and transcription factors that control cell proliferation,apoptosis,and differentiation,with the Wnt/β-catenin signaling pathway playin... Tooth morphogenesis is orchestrated by a complex interplay of signaling pathways and transcription factors that control cell proliferation,apoptosis,and differentiation,with the Wnt/β-catenin signaling pathway playing a pivotal role.However,the comprehensive regulatory mechanisms of Wnt/β-catenin signaling remain largely unclear.Smad7,a key antagonist of the TGF-βsuperfamily,is essential for maintaining tissue homeostasis and ensuring proper cellular function.Our previous study has demonstrated that Smad7 knockout in mice leads to impaired proliferative property of tooth germ cells,resulting in small molars.Here,we identified SMAD7 expression in human dental papilla and dental pulp,colocalized with β-CATENIN and cell proliferationrelated proteins.RNA sequencing analysis revealed a significant reduction in Wnt signaling activity in Smad7-deficient mouse tooth germs.Using lentivirus transfection,we established SMAD7-knockdown human dental papilla stem cells,which manifested remarkably blunt proliferation rate,along with diminished Wnt signaling activity.In vivo transplantation investigations further revealed the indispensable role of SMAD7 in dentin formation.Mechanistically,we revealed that β-CATENIN interacts with P-SMAD2/3 and SMAD7 through co-immunoprecipitation and yeast two-hybrid assays.Inhibition of TGF-β pathway or disruption of SMAD7/β-CATENIN transcription factor complex formation potently impacted Wnt/β-catenin activities,indicating both direct and indirect regulatory mechanisms.These findings highlight the critical role of SMAD7 in the proliferation and diffe rentiation of human dental stem cells,which could contribute to dental tissue regeneration and engineering. 展开更多
关键词 Dental stem cells Wnt catenin signaling signaling pathways transcription factors Tooth regeneration tooth morphogenesis maintaining tissue homeostasis TGF cascade
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