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Near real-time monitoring of carbon effects from continuous forest change in rapidly urbanizing region of China from 2000 to 2020
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作者 Dou Zhang Xiaojing Tang +5 位作者 Shuaizhi Lu Xiaolei Geng Zhaowu Yu Yujing Xie Si Peng Xiangrong Wang 《Forest Ecosystems》 2025年第4期688-700,共13页
Forest carbon sinks are crucial for mitigating urban climate change.Their effectiveness depends on the balance between gross carbon losses and gains.However,quantitative and continuous monitoring of forest change/dist... Forest carbon sinks are crucial for mitigating urban climate change.Their effectiveness depends on the balance between gross carbon losses and gains.However,quantitative and continuous monitoring of forest change/disturbance carbon fluxes is still insufficient.To address this gap,we integrated an improved spatial carbon bookkeeping(SBK)model with the continuous change detection and classification(CCDC)algorithm,long-term Landsat observations,and ground measurements to track carbon emissions,uptakes,and net changes from forest cover changes in the Yangtze River Delta(YRD)of China from 2000 to 2020.The SBK model was refined by incorporating heterogeneous carbon response functions.Our results reveal that carbon emissions(-3.88 Tg C·year^(-1))were four times greater than carbon uptakes(0.93 Tg C·year^(-1))from forest cover changes in the YRD during 2000-2020,despite a net forest cover gain of 10.95×10^(4) ha.These findings indicate that the carbon effect per hectare of forest cover loss is approximately 4.5 times that of forest cover gain.The asymmetric carbon effect suggests that forest cover change may act as a carbon source even with net-zero or net-positive forest cover change.Furthermore,carbon uptakes from forest gains in the YRD during 2000-2020 could only offset 0.28% of energy-related carbon emissions from 2000 to 2019.Urban and agricultural expansions accounted for 37% and 10% of carbon emissions,respectively,while the Grain for Green Project contributed to 45% of carbon uptakes.Our findings underscore the necessity of understanding the asymmetric carbon effects of forest cover loss and gain to accurately assess the capacity of forest carbon sinks. 展开更多
关键词 continuous forest cover change Asymmetric carbon effects continuous change detection and classification(CCDC)algorithm Improved spatial carbon bookkeeping(SBK)model Google Earth Engine(GEE)
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Electroacoustic tomography with dual-frequency array for real-time monitoring of electroporation
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作者 Luke Xu Yifei Xu Liangzhong Xiang 《Journal of Innovative Optical Health Sciences》 2026年第1期45-55,共11页
Electroacoustic Tomography(EAT)is an imaging technique that detects ultrasound waves induced by electrical pulses,offering a solution for real-time electroporation monitoring.This study presents EAT system using a dua... Electroacoustic Tomography(EAT)is an imaging technique that detects ultrasound waves induced by electrical pulses,offering a solution for real-time electroporation monitoring.This study presents EAT system using a dual-frequency ultrasound array.The broadband nature of electroacoustic signals requires ultrasound detector to cover both the high-frequency range(around 6MHz)signals generated by small targets and the low-frequency range(around 1MHz)signals generated by large targets.In our EAT system,we use the 6 MHz array to detect high-frequency signals from the electrodes,and the 1 MHz array for the electrical field.To test this,we conducted simulations using COMSOL Multiphysics^(®) and MATLAB's k-Wave toolbox,followed by experiments using a custom-built setup with a dual-frequency transducer and real-time data acquisition.The results demonstrated that the dual-frequency EAT system could accurately and simultaneously monitor the electroporation process,effectively showing both the treatment area and electrode placement with the application of 1 kV electric pulses with 100 ns duration.The axial resolution of the 6MHz array for EAT was 0.45 mm,significantly better than the 2mm resolution achieved with the 1MHz array.These findings validate the potential of dual-frequency EAT as a superior method for real-time electroporation monitoring. 展开更多
关键词 DUAL-FREQUENCY electroacoustic imaging real-time ELECTROPORATION
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PIDINet-MC:Real-Time Multi-Class Edge Detection with PiDiNet
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作者 Mingming Huang Yunfan Ye Zhiping Cai 《Computers, Materials & Continua》 2026年第2期1983-1999,共17页
As a fundamental component in computer vision,edges can be categorized into four types based on discontinuities in reflectance,illumination,surface normal,or depth.While deep CNNs have significantly advanced generic e... As a fundamental component in computer vision,edges can be categorized into four types based on discontinuities in reflectance,illumination,surface normal,or depth.While deep CNNs have significantly advanced generic edge detection,real-time multi-class semantic edge detection under resource constraints remains challenging.To address this,we propose a lightweight framework based on PiDiNet that enables fine-grained semantic edge detection.Our model simultaneously predicts background and four edge categories from full-resolution inputs,balancing accuracy and efficiency.Key contributions include:a multi-channel output structure expanding binary edge prediction to five classes,supported by a deep supervision mechanism;a dynamic class-balancing strategy combining adaptive weighting with physical priors to handle extreme class imbalance;and maintained architectural efficiency enabling real-time inference.Extensive evaluations on BSDS-RIND show our approach achieves accuracy competitive with state-of-the-art methods while operating in real time. 展开更多
关键词 Multi-class edge detection real-time LIGHTWEIGHT deep supervision
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Block-Wise Sliding Recursive Wavelet Transform and Its Application in Real-Time Vehicle-Induced Signal Separation
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作者 Jie Li Nan An Youliang Ding 《Structural Durability & Health Monitoring》 2026年第1期1-22,共22页
Vehicle-induced response separation is a crucial issue in structural health monitoring(SHM).This paper proposes a block-wise sliding recursive wavelet transform algorithm to meet the real-time processing requirements ... Vehicle-induced response separation is a crucial issue in structural health monitoring(SHM).This paper proposes a block-wise sliding recursive wavelet transform algorithm to meet the real-time processing requirements of monitoring data.To extend the separation target from a fixed dataset to a continuously updating data stream,a block-wise sliding framework is first developed.This framework is further optimized considering the characteristics of real-time data streams,and its advantage in computational efficiency is theoretically demonstrated.During the decomposition and reconstruction processes,information from neighboring data blocks is fully utilized to reduce algorithmic complexity.In addition,a delay-setting strategy is introduced for each processing window to mitigate boundary effects,thereby balancing accuracy and efficiency.Simulated signal experiments are conducted to determine the optimal delay configuration and to verify the algorithm’s superior performance,achieving a lower Root Mean Square Error(RMSE)and only 0.0249 times the average computational time compared with the original algorithm.Furthermore,strain signals from the Lieshi River Bridge are employed to validate the method.The proposed algorithm successfully separates the static trend from vehicle-induced responses in real time across different sampling frequencies,demonstrating its effectiveness and applicability in real-time bridge monitoring. 展开更多
关键词 Wavelet transform vehicle-induced signal separation real-time structure monitoring
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Effects of Continuous Care on Children with Enterostomy and Their Families in China
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作者 Shanwei Li Ying Wang Yan Tang 《Journal of Clinical and Nursing Research》 2026年第1期400-408,共9页
Background:Continuous care for children with enterostomy and their families has been gaining popularity in China.Objective:To evaluate the feasibility of continuous care for children with enterostomy and their familie... Background:Continuous care for children with enterostomy and their families has been gaining popularity in China.Objective:To evaluate the feasibility of continuous care for children with enterostomy and their families in China.Methods:The PubMed,Web of Science,Embase,Cochrane Library,EBSCO,CNKI,CBM,VIP,and WanFang were searched for clinical trials until December 30,2025.Two reviewers independently searched articles,evaluated quality and extracted data.This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA).Results:33 studies involving 2774 participants were included.The meta-analysis showed that continuous care strategy can significantly reduce the incidence of complications in children with enterostomy(OR=0.20,95%CI=0.16-0.26,p<0.001,I2=0%),effectively improve the family caregiver ability for enterostomy(MD=-10.34,95%CI=-13.82 to-6.85,p<0.001,I2=99%),shorten the time for family members to replace stoma bags(MD=-13.57,95%CI=-19.66 to-7.49,p<0.001,I2=100%),and alleviate negative emotions such as anxiety(SMD=-1.80,95%CI=-2.36 to-1.23,p<0.001,I2=92%)and depression(SMD=-1.54,95%CI=-2.04 to-1.04,p<0.001,I2=89%)in the families of the affected children.Conclusions:Continuous care can reduce complications of enterostomy in children,improve the family caregiver ability for enterostomy and alleviate negative emotions of family members such as anxiety and depression. 展开更多
关键词 continuous care Pediatric enterostomy Family members Enterostomy nursing META-ANALYSIS
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Synergistic design of ultra-wide low-frequency continuous bandgap metastructure for audible noise attenuation
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作者 Dongxu GUO Xiaolong ZHANG +2 位作者 Ruilan TIAN Xiangyang LI Minghao WANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第3期473-496,共24页
Local resonant acoustic metamaterials have broad applications in sound insulation,yet their single-configuration designs often exhibit limited and discontinuous bandgap widths,hindering full-frequency noise attenuatio... Local resonant acoustic metamaterials have broad applications in sound insulation,yet their single-configuration designs often exhibit limited and discontinuous bandgap widths,hindering full-frequency noise attenuation across the human auditory range.This study presents a double-phase fidget-spinner-shaped acoustic metamaterial(DFAM),specifically designed to achieve an ultra-broad,low-frequency continuous bandgap by means of synergistic structural optimization,enabling effective and robust control of audible noise.Based on Bloch's theorem and the finite element method,the dispersion relation of the DFAM structure is calculated and verified by the transmission loss curves.The propagation characteristics of sound waves within the structure are further analyzed for noise frequencies that fall within the passband.The influence of the geometric and physical parameters on the bandgap is investigated,and the corresponding transmission loss in the propagation direction is further calculated.A hybrid collaborative design strategy,leveraging multi-parameter optimization and bandgap complementarity,is developed to construct a metastructure with continuous bandgap coverage from 20 Hz to 1000 Hz.The resulting metastructure demonstrates exceptional broadband noise attenuation,achieving a total bandgap width of 876.3 Hz(87.63% of the target range)with the transmission loss up to-762.78 d B in a three-periodic arrangement.The simulation and experimental results for the transmission loss of the DFAM metastructure show strong agreement in the low-frequency range.This work provides a novel framework for designing ultra-wide low-frequency continuous bandgap metastructures,offering significant potential for noise mitigation in complex environments. 展开更多
关键词 acoustic metastructure local resonance continuous bandgap noise attenuation synergistic design
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Batch and continuous-flow asymmetric synthesis of d-pantothenic acid precursor enabled by immobilized ketoreductase mutant
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作者 Pan Hu Xiaofan Wu +6 位作者 Yi An Xianjing Zheng Liang Gao Yuan Tao Yajiao Zhang Zedu Huang Fener Chen 《Chinese Chemical Letters》 2026年第2期471-476,共6页
We report an immobilized enzyme-catalyzed batch and continuous-flow synthesis of optically pure ethyl(R)-pantothenate((R)-PaOEt),the direct precursor of d-pantothenic acid.Firstly,a ketoreductase mutant designated as ... We report an immobilized enzyme-catalyzed batch and continuous-flow synthesis of optically pure ethyl(R)-pantothenate((R)-PaOEt),the direct precursor of d-pantothenic acid.Firstly,a ketoreductase mutant designated as M2,carrying two-point mutations of F97L and M242F relative to the wild-type SSCR,was constructed by site-directed mutagenesis,exhibited simultaneously improved activity toward ethyl 2′-ketopantothenate(K-PaOEt)and isopropanol,and could effectively catalyze the stereoselective reduction of K-PaOEt to(R)-PaOEt by using isopropanol as the sacrificial co-substrate to regenerate NADPH.After screening six commercially available carriers,an amino resin LXTE-700 was identified as the best solid support for the immobilization of M2 via the glutaraldehyde activation method.Upon optimization of the immobilization process and reaction conditions,the fabricated immobilized enzyme M2@amino resin demonstrated excellent recyclability and reusability,with the complete conversion of K-PaOEt to(R)-PaOEt being still realized after 12 cycles of reuse.Finally,M2@amino resin-catalyzed synthesis of(R)-PaOEt was successfully implemented in continuous-flow,accomplishing a 6.3 times higher space-time yield than that with the batch synthesis(529.2 versus 84 g L^(-1) d^(-1)).Our developed flow biocatalysis system also features an outstanding operational stability,as evidenced by the 100%conversion rate achieved after 15 consecutive days of operation. 展开更多
关键词 Asymmetric synthesis continuous flow synthesis Enzyme immobilization KETOREDUCTASE D-Pantothenic acid
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Energy relief effect of real-time drilling to prevent rockburst in high-stress rock
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作者 Zhichao He Fengqiang Gong +2 位作者 Li Ren Weimin Yang Xuezhen Wu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1460-1475,共16页
To investigate the energy relief effect of real-time drilling in preventing rockburst in high-stress rock,a series of high-stress real-time drilling uniaxial compression tests were conducted on red sandstone specimens... To investigate the energy relief effect of real-time drilling in preventing rockburst in high-stress rock,a series of high-stress real-time drilling uniaxial compression tests were conducted on red sandstone specimens using the SG4500 drilling rig.Results showed that the mechanical behavior(i.e.peak strength and rockburst intensity)of the rock was weakened under high-stress real-time drilling and exhibited a downward trend as the drilling diameter increased.The real-time drilling energy dissipation index(ERD)was proposed to characterize the energy relief during high-stress real-time drilling.The ERD exhibited a linear increase with the real-time drilling diameter.Furthermore,the elastic strain energy of post-drilling rock showed a linear relationship with the square of stress across different stress levels,which also applied to the peak elastic strain energy and the square of peak stress.This findingreveals the intrinsic link between the weakening effect of peak elastic strain energy and peak strength due to high-stress real-time drilling,confirmingthe consistency between energy relief and pressure relief effects.By establishing relationships among rockburst proneness,peak elastic strain energy,and peak strength,it was demonstrated that high-stress real-time drilling reduces rockburst proneness through energy dissipation.Specifically,both peak elastic strain energy and rockburst proneness decreased with larger drill bit diameters,consistent with reductions in peak strength,rockburst intensity,and fractal dimensions of high-stress real-time drilled rock.These results validate the energy relief mechanism of real-time drilling in mitigating rockburst risks. 展开更多
关键词 Rock mechanics ROCKBURST real-time drilling Drilling energy relief Energy storage capacity Rockburst proneness
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Experimental study on real-time monitoring of surrounding rock 3D wave velocity structure and failure zone in deep tunnels
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作者 Hongyun Yang Chuandong Jiang +4 位作者 Yong Li Zhi Lin Xiang Wang Yifei Wu Wanlin Feng 《International Journal of Mining Science and Technology》 2026年第2期423-437,共15页
An innovative real-time monitoring method for surrounding rock damage based on microseismic time-lapse double-difference tomography is proposed for delayed dynamic damage identification and insufficient detection of a... An innovative real-time monitoring method for surrounding rock damage based on microseismic time-lapse double-difference tomography is proposed for delayed dynamic damage identification and insufficient detection of adverse geological conditions in deep-buried tunnel construction.The installation techniques for microseismic sensors were optimized by mounting sensors at bolt ends which significantly improves signal-to-noise ratio(SNR)and anti-interference capability compared to conventional borehole placement.Subsequently,a 3D wave velocity evolution model that incorporates construction-induced disturbances was established,enabling the first visualization of spatiotemporal variations in surrounding rock wave velocity.It finds significant wave velocity reduction near the tunnel face,with roof and floor damage zones extending 40–50 m;wave velocities approaching undisturbed levels at 15 m ahead of the working face and on the laterally undisturbed side;pronounced spatial asymmetry in wave velocity distribution—values on the left side exceed those on the right,with a clear stress concentration or transition zone located 10–15 m;and systematically lower velocities behind the face than in front,indicating asymmetric rock damage development.These results provide essential theoretical support and practical guidance for optimizing dynamic construction strategies,enabling real-time adjustment of support parameters,and establishing safety early warning systems in deep-buried tunnel engineering. 展开更多
关键词 Deep-buried tunnel Microseismic monitoring Wave velocity tomography Surrounding rock damage zone real-time monitoring
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A Hybrid Deep Learning Approach for Real-Time Cheating Behaviour Detection in Online Exams Using Video Captured Analysis
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作者 Dao Phuc Minh Huy Gia Nhu Nguyen Dac-Nhuong Le 《Computers, Materials & Continua》 2026年第3期1179-1198,共20页
Online examinations have become a dominant assessment mode,increasing concerns over academic integrity.To address the critical challenge of detecting cheating behaviours,this study proposes a hybrid deep learning appr... Online examinations have become a dominant assessment mode,increasing concerns over academic integrity.To address the critical challenge of detecting cheating behaviours,this study proposes a hybrid deep learning approach that combines visual detection and temporal behaviour classification.The methodology utilises object detection models—You Only Look Once(YOLOv12),Faster Region-based Convolutional Neural Network(RCNN),and Single Shot Detector(SSD)MobileNet—integrated with classification models such as Convolutional Neural Networks(CNN),Bidirectional Gated Recurrent Unit(Bi-GRU),and CNN-LSTM(Long Short-Term Memory).Two distinct datasets were used:the Online Exam Proctoring(EOP)dataset from Michigan State University and the School of Computer Science,Duy Tan Unievrsity(SCS-DTU)dataset collected in a controlled classroom setting.A diverse set of cheating behaviours,including book usage,unauthorised interaction,internet access,and mobile phone use,was categorised.Comprehensive experiments evaluated the models based on accuracy,precision,recall,training time,inference speed,and memory usage.We evaluate nine detector-classifier pairings under a unified budget and score them via a calibrated harmonic mean of detection and classification accuracies,enabling deployment-oriented selection under latency and memory constraints.Macro-Precision/Recall/F1 and Receiver Operating Characteristic-Area Under the Curve(ROC-AUC)are reported for the top configurations,revealing consistent advantages of object-centric pipelines for fine-grained cheating cues.The highest overall score is achieved by YOLOv12+CNN(97.15%accuracy),while SSD-MobileNet+CNN provides the best speed-efficiency trade-off for edge devices.This research provides valuable insights into selecting and deploying appropriate deep learning models for maintaining exam integrity under varying resource constraints. 展开更多
关键词 Online exam proctoring cheating behavior detection deep learning real-time monitoring object detection human behavior recognition
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Real-time decision support for bolter recovery safety:Long short-term memory network-driven aircraft sequencing
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作者 Wei Han Changjiu Li +4 位作者 Xichao Su Yong Zhang Fang Guo Tongtong Yu Xuan Li 《Defence Technology(防务技术)》 2026年第2期184-205,共22页
The highly dynamic nature,strong uncertainty,and coupled multiple safety constraints inherent in carrier aircraft recovery operations pose severe challenges for real-time decision-making.Addressing bolter scenarios,th... The highly dynamic nature,strong uncertainty,and coupled multiple safety constraints inherent in carrier aircraft recovery operations pose severe challenges for real-time decision-making.Addressing bolter scenarios,this study proposes an intelligent decision-making framework based on a deep long short-term memory Q-network.This framework transforms the real-time sequencing for bolter recovery problem into a partially observable Markov decision process.It employs a stacked long shortterm memory network to accurately capture the long-range temporal dependencies of bolter event chains and fuel consumption.Furthermore,it integrates a prioritized experience replay training mechanism to construct a safe and adaptive scheduling system capable of millisecond-level real-time decision-making.Experimental demonstrates that,within large-scale mass recovery scenarios,the framework achieves zero safety violations in static environments and maintains a fuel safety violation rate below 10%in dynamic scenarios,with single-step decision times at the millisecond level.The model exhibits strong generalization capability,effectively responding to unforeseen emergent situations—such as multiple bolters and fuel emergencies—without requiring retraining.This provides robust support for efficient carrier-based aircraft recovery operations. 展开更多
关键词 Carrier-based aircraft Recovery scheduling Deep reinforcement learning Long short-term memory networks Dynamic real-time decision-making
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Key points for the Chen's transpancreatic continuous U-suture technique for pancreaticojejunostomy
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作者 Yan Chen Qi Cheng +4 位作者 Lin Chen Erlei Zhang Shuai Xiang Changhai Li Xiaoping Chen 《Oncology and Translational Medicine》 2026年第1期4-9,共6页
1.Introduction.Pancreaticoduodenectomy is an essential surgical procedure for the treatment of malignant tumors in the pancreatic head,distal common bile duct,and duodenal papilla,and is widely used in clinical practi... 1.Introduction.Pancreaticoduodenectomy is an essential surgical procedure for the treatment of malignant tumors in the pancreatic head,distal common bile duct,and duodenal papilla,and is widely used in clinical practice.One of the primary determinants of surgical success is the durability of the pancreaticojejunal anastomosis. 展开更多
关键词 PANCREATICODUODENECTOMY surgical procedure malignant tumors pancreaticojejunal anastomosis durability surgical success transpancreatic continuous USuture technique
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Effect of ladle shroud immersion depth on unsteady three-phase flow in continuous casting tundish during ladle change-over process
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作者 Yu-Chao Yao Zhong-Qiu Liu +3 位作者 Yu-Ze Wei Ning Wang Jun Yang Bao-Kuan Li 《Journal of Iron and Steel Research International》 2026年第1期443-457,共15页
The transient phenomena of re-oxidation and slag entrapment occurring in the tundish during the ladle change-over process have been proven detrimental to clean steel production.Therefore,an unsteady three-phase turbul... The transient phenomena of re-oxidation and slag entrapment occurring in the tundish during the ladle change-over process have been proven detrimental to clean steel production.Therefore,an unsteady three-phase turbulence model,coupling velocity,temperature,and phase field was established to study the effect of the ladle shroud immersion depth on the slag eye formation,slag entrainment,slag dragging,air dragging,and flow characteristics during the ladle change-over process of a two-strand tundish.The results showed that reducing the immersion depth decreases the high-velocity region area under the slag layer in the quasi-steady process.During the emptying stage,as the molten bath level gradually decreases,the outlet temperature exhibits a trend of initially decreasing and subsequently increasing across all three shroud immersion depths.However,under a 210 mm shroud immersion depth,molten slag and air are dragged into the shroud,forming slag droplets and causing significant fluctuations,with a maximum scalar velocity of 0.0764 m/s at the monitoring point.In the filling stage,air and molten slag are dragged into the molten bath,forming bubbles and slag droplets at an immersion depth of 210 mm.Bubbles are observed within the molten slag layer,which can readily cause an emulsification phenomenon,making it easier to be dragged as slag droplets.Additionally,the slag eye area measured under 210 mm immersion depth at 45 s is 0.303 m^(2),while the maximum scalar velocity of 2.4259 m/s is detected at 12 s.At an immersion depth of 360 mm,the average area of the slag eye is minimized to 0.06268 m2,with corresponding variances of 0.006753,representing the optimal immersion depth. 展开更多
关键词 continuous casting tundish Ladle change-over Ladle shroud Immersion depth Three-phase flow Unsteady state
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Characterization of the formation of slag rims of mold powder during hypo-peritectic steel continuous casting based on full-sectional microstructures
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作者 Zhiqiang Peng Zibing Hou +2 位作者 Shuxian Xu Ping Tang Guanghua Wen 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期567-578,共12页
A full-sectional microstructure characterization method was developed to investigate the formation of coarse slag rims during the continuous casting of hypo-peritectic steel.The cross-sectional microstructural analysi... A full-sectional microstructure characterization method was developed to investigate the formation of coarse slag rims during the continuous casting of hypo-peritectic steel.The cross-sectional microstructural analysis of typical slag rims for two highly crystalline powders revealed that their formation was primarily driven by the solidification of the liquid slag.Distinct differences were observed in the microstructures of slag rims from the two powders.Powder A(characterized by a higher breaking temperature and viscosity)displayed alternating lamellar microstructures of coarse and fine phases,with the coarse phases composed of akermanite-gehlenite transition phases.In contrast,powder B(with a lower breaking temperature and viscosity)predominantly comprised regular akermanite-gehlenite crystals interspersed with a certain amount of glassy phases.Numerical simulations of a three-phase fluid flow coupled with heat transfer indicate that slag rim formation correlates with mold oscillation.Solidification of the liquid slag at the slag rim front predominantly occurs during the negative stroke of the mold oscillation.The average heating rate during the ascending stage of the mold reaches approximately 100 K·s^(−1),whereas the average cooling rate during the descending stage attains 400 K·s^(−1).This temperature variation leads to the formation of lamellar microstructures,whereas the ascending stage promotes the formation of coarse structures and thicker slag rims.Based on the powder properties,two distinct formation pathways exist for highly crystalline mold powders.For the powders with a higher breaking temperature,higher viscosity,and narrower solidification range(powder A),coarse microstructures and thicker slag rims were preferentially formed.For powders with lower breaking temperature and viscosity and wider solidification ranges(powder B),the liquid slag resisted rapid solidification,and the extended mushy zone allowed the partial liquid slag to persist at the slag rim front,promoting the formation of a thin slag rim.This study enhances the understanding of slag rim formation in highly crystalline mold powders and provides critical insights into the control of longitudinal surface cracks in hypo-peritectic steel. 展开更多
关键词 hypo-peritectic steel longitudinal surface crack continuous casting slag rim full-sectional microstructures mold powder
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Asymmetric flow in multi-mode continuous casting and rolling mold under electromagnetic braking
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作者 Jing-Pei Shi Xiao-Xian Shang +3 位作者 Xin-Yue Shi Zhan-Long Plao Cai-Jun Zhang Li-Guang Zhu 《Journal of Iron and Steel Research International》 2026年第1期159-179,共21页
The flow behavior of molten steel in the thin slab mold under high casting speed conditions was investigated,with a focus on the multi-mode continuous casting and rolling mold.A steel-slag two-phase flow model was est... The flow behavior of molten steel in the thin slab mold under high casting speed conditions was investigated,with a focus on the multi-mode continuous casting and rolling mold.A steel-slag two-phase flow model was established using large eddy simulation,the volume of fluid,and magnetohydrodynamics methods through numerical simulation.The maximum flow velocity and wave height at the steel-slag interface within the mold are critical evaluation criteria for analyzing asymmetric flow under varying casting speeds and electromagnetic braking.The results indicate that the asymmetric flows within the mold do not occur synchronously.The severity of the asymmetric flow correlates with the velocity difference across the steel-slag interface.A greater biased flow prolongs the time required to revert to a steady state.When the magnetic field intensity is set to 0.24 T and the magnetic pole position is at 390 mm from the steel-slag interface,this configuration can reduce the velocity of the steel-slag interface,thereby mitigating the asymmetric flow.Additionally,it can diminish the velocity,impact depth,and impact intensity on the narrow face of the jet,thus improving the distribution of velocity and turbulent kinetic energy within the mold.This configuration prolongs the time required for the steel-slag interface to transition from a stable state to its maximum velocity and shortens the time for the interface to return to stability from an unstable state.Moreover,it ensures the positional stability of the steel-slag interface,confining its position within−3 mm. 展开更多
关键词 Multi-mode continuous casting and rolling mold Asymmetric flow Steel-slag interface Turbulent kinetic energy Electromagnetic braking
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Micro-failure process and failure mechanism of brittle rock under uniaxial compression using continuous real-time wave velocity measurement 被引量:4
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作者 WU Zhi-jun WANG Zhi-yang +2 位作者 FAN Li-feng WENG Lei LIU Quan-sheng 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第2期556-571,共16页
In this study,the micro-failure process and failure mechanism of a typical brittle rock under uniaxial compression are investigated via continuous real-time measurement of wave velocities.The experimental results indi... In this study,the micro-failure process and failure mechanism of a typical brittle rock under uniaxial compression are investigated via continuous real-time measurement of wave velocities.The experimental results indicate that the evolutions of wave velocities became progressively anisotropic under uniaxial loading due to the direction-dependent development of micro-damage.A wave velocity model considering the inner anisotropic crack evolution is proposed to accurately describe the variations of wave velocities during uniaxial compression testing.Based on which,the effective elastic parameters are inferred by a transverse isotropic constitutive model,and the evolutions of the crack density are inversed using a self-consistent damage model.It is found that the propagation of axial cracks dominates the failure process of brittle rock under uniaxial loading and oblique shear cracks develop with the appearance of macrocrack. 展开更多
关键词 elastic wave velocity brittle rock failure uniaxial compression test continuous real-time measurement anisotropic damage evolution theory and modelling
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Real-Time Optimization Model for Continuous Reforming Regenerator 被引量:1
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作者 Jiang Shubao Jiang Hongbo +1 位作者 Li Zhenming Tian Jianhui 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2021年第3期90-103,共14页
An approach for the simulation and optimization of continuous catalyst-regenerative process of reforming is proposed in this paper.Compared to traditional method such as finite difference method,the orthogonal colloca... An approach for the simulation and optimization of continuous catalyst-regenerative process of reforming is proposed in this paper.Compared to traditional method such as finite difference method,the orthogonal collocation method is less time-consuming and more accurate,which can meet the requirement of real-time optimization(RTO).In this paper,the equation-oriented method combined with the orthogonal collocation method and the finite difference method is adopted to build the RTO model for catalytic reforming regenerator.The orthogonal collocation method was adopted to discretize the differential equations and sequential quadratic programming(SQP)algorithm was used to solve the algebraic equations.The rate constants,active energy and reaction order were estimated,with the sum of relative errors between actual value and simulated value serving as optimization objective function.The model can quickly predict the fields of component concentration,temperature and pressure inside the regenerator under different conditions,as well as the real-time optimized conditions for industrial reforming regenerator. 展开更多
关键词 catalytic reforming regenerator KINETICS model orthogonal collocation method real-time optimization
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Preliminary prospective study of real-time post-gastrectomy glycemic fluctuations during dumping symptoms using continuous glucose monitoring
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作者 Motonari Ri Souya Nunobe +6 位作者 Satoshi Ida Naoki Ishizuka Shinichiro Atsumi Rie Makuuchi Koshi Kumagai Manabu Ohashi Takeshi Sano 《World Journal of Gastroenterology》 SCIE CAS 2021年第23期3386-3395,共10页
BACKGROUND Although dumping symptoms constitute the most common post-gastrectomy syndromes impairing patient quality of life,the causes,including blood sugar fluctuations,are difficult to elucidate due to limitations ... BACKGROUND Although dumping symptoms constitute the most common post-gastrectomy syndromes impairing patient quality of life,the causes,including blood sugar fluctuations,are difficult to elucidate due to limitations in examining dumping symptoms as they occur.AIM To investigate relationships between glucose fluctuations and the occurrence of dumping symptoms in patients undergoing gastrectomy for gastric cancer.METHODS Patients receiving distal gastrectomy with Billroth-I(DG-BI)or Roux-en-Y reconstruction(DG-RY)and total gastrectomy with RY(TG-RY)for gastric cancer(March 2018-January 2020)were prospectively enrolled.Interstitial tissue glycemic profiles were measured every 15 min,up to 14 d,by continuous glucose monitoring.Dumping episodes were recorded on 5 patient-selected days by diary.Within 3 h postprandially,dumping-associated glycemic changes were defined as a dumping profile,those without symptoms as a control profile.These profiles were compared.RESULTS Thirty patients were enrolled(10 DG-BI,10 DG-RY,10 TG-RY).The 47 early dumping profiles of DG-BI showed immediately sharp rises after a meal,which 47 control profiles did not(P<0.05).Curves of the 15 late dumping profiles of DG-BI were similar to those of early dumping profiles,with lower glycemic levels.DGRY and TG-RY late dumping profiles(7 and 13,respectively)showed rapid glycemic decreases from a high glycemic state postprandially to hypoglycemia,with a steeper drop in TG-RY than in DG-RY.CONCLUSION Postprandial glycemic changes suggest dumping symptoms after standard gastrectomy for gastric cancer.Furthermore,glycemic profiles during dumping may differ depending on reconstruction methods after gastrectomy. 展开更多
关键词 Gastric cancer GASTRECTOMY Billroth-I reconstruction Roux-en-Y reconstruction Dumping syndrome continuous glucose monitoring
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Ultra-thin temperature controllable microwell array chip for continuous real-time high-resolution imaging of living single cells
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作者 Yuanyuan Wu Lei Zhao +3 位作者 Yaran Chang Liang Zhao Guangsheng Guo Xiayan Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第11期3446-3449,共4页
Single-cell imaging,a powerful analytical method to study single-cell behavior,such as gene expression and protein profiling,provides an essential basis for modern medical diagnosis.The coding and localization functio... Single-cell imaging,a powerful analytical method to study single-cell behavior,such as gene expression and protein profiling,provides an essential basis for modern medical diagnosis.The coding and localization function of microfluidic chips has been developed and applied in living single-cell imaging in recent years.Simultaneously,chip-based living single-cell imaging is also limited by complicated trapping steps,low cell utilization,and difficult high-resolution imaging.To solve these problems,an ultra-thin temperature-controllable microwell array chip(UTCMA chip)was designed to develop a living single-cell workstation in this study for continuous on-chip culture and real-time high-resolution imaging of living single cells.The chip-based on ultra-thin ITO glass is highly matched with an inverted microscope(or confocal microscope)with a high magnification objective(100×oil lens),and the temperature of the chip can be controlled by combining it with a home-made temperature control device.High-throughput single-cell patterning is realized in one step when the microwell array on the chip uses hydrophilic glass as the substrate and hydrophobic SU-8 photoresist as the wall.The cell utilization rate,single-cell capture rate,and microwell occupancy rate are all close to 100%in the microwell array.This method will be useful in rare single-cell research,extending its application in the biological and medical-related fields,such as early diagnosis of disease,personalized therapy,and research-based on single-cell analysis. 展开更多
关键词 Ultra-thin microchip Temperature controllable Living single cells One-step patterning continuous culture High-resolution imaging
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RESEARCH ON A REAL-TIME CONTROL SYSTEM OF LOW POWER DISSIPATION FOR CONTINUOUS CYCLIC PERITONEAL DIALYSIS(CCPD) CYCLER
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作者 Peng Yi Lu Songfang +1 位作者 Kong Hua Yang Zibin(Institute of Basic Medical Seiences,Chinese Academy of Medical SciencesSchool of Basic Medicine,Peking Union Medical College,Beijing 100005,China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1998年第1期22-25,共4页
A low power dissipation control system for continuous cyclic peritoneal dialysis (CCPD) cycler and its characteristics are reported. Combined withhemodialysis and renal transplantation, peritoneal dialysis is used mai... A low power dissipation control system for continuous cyclic peritoneal dialysis (CCPD) cycler and its characteristics are reported. Combined withhemodialysis and renal transplantation, peritoneal dialysis is used mainly for thetreatment of renal failure. CCPD has been developed during 1980's. It provided automatic dialysis procedures during the night to avoid interruptions in patients'dailyroutine. Furthermore,there is a remarkable decrease in peritonitis occurance usingCCPD. The control system is a critical part for CCPD cycler. The system is approvedto be reliable and flexible in practical experiments. When AC power failure,the system can still ensure the completion of dialysis. 展开更多
关键词 continuous CYCLIC PERITONEAL DIALYSIS (CCPD) control system SINGLE-CHIP MICROCOMPUTER low power dissipation
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