Interfacial solar-driven water evaporation offers a sustainable route to clean water production,but faces critical challenges of salt accumulation and organic contamination in complex industrial wastewater treatment.T...Interfacial solar-driven water evaporation offers a sustainable route to clean water production,but faces critical challenges of salt accumulation and organic contamination in complex industrial wastewater treatment.To address these challenges,we engineered a multifunctional 3D-printed hydrogel evaporator with vertically aligned grid architectures and hierarchical porosity.This unique structure promotes rapid water replenishment and Marangoni-driven salt back-diffusion through millimeter-scale channels,effectively preventing salt crystallization.By integrating carbon black and the metal-organic framework PCN-224 into the printing ink,we constructed a dual-functional photothermal-photocatalytic system.This synergistic combination not only enhances light absorption and photothermal conversion but also significantly reduces the water evaporation enthalpy.Coupled with heat-accelerated reaction kinetics,the system achieves efficient broad-spectrum photocatalytic degradation of organic pollutants.The resultant composite evaporator attains a high water evaporation rate of 2.04 kg m-2h-1under one-sun illumination,maintaining stable performance across a wide salinity range.Simultaneously,it degraded 96.5%of rhodamine B within 60 min under 1.5 kW m-2irradiation.展开更多
Battery management systems(BMSs) play a vital role in ensuring efficient and reliable operations of lithium-ion batteries.The main function of the BMSs is to estimate battery states and diagnose battery health using b...Battery management systems(BMSs) play a vital role in ensuring efficient and reliable operations of lithium-ion batteries.The main function of the BMSs is to estimate battery states and diagnose battery health using battery open-circuit voltage(OCV).However,acquiring the complete OCV data online can be a challenging endeavor due to the time-consuming measurement process or the need for specific operating conditions required by OCV estimation models.In addressing these concerns,this study introduces a deep neural network-combined framework for accurate and robust OCV estimation,utilizing partial daily charging data.We incorporate a generative deep learning model to extract aging-related features from data and generate high-fidelity OCV curves.Correlation analysis is employed to identify the optimal partial charging data,optimizing the OCV estimation precision while preserving exceptional flexibility.The validation results,using data from nickel-cobalt-magnesium(NCM) batteries,illustrate the accurate estimation of the complete OCV-capacity curve,with an average root mean square errors(RMSE) of less than 3 mAh.Achieving this level of precision for OCV estimation requires only around 50 s collection of partial charging data.Further validations on diverse battery types operating under various conditions confirm the effectiveness of our proposed method.Additional cases of precise health diagnosis based on OCV highlight the significance of conducting online OCV estimation.Our method provides a flexible approach to achieve complete OCV estimation and holds promise for generalization to other tasks in BMSs.展开更多
THE More Electric Aircraft(MEA)/All Electric Aircraft(AEA)system is being widely recognized as the future for the aerospace industry to meet the power demands of increasing electric loads,reduce aircraft emissions,imp...THE More Electric Aircraft(MEA)/All Electric Aircraft(AEA)system is being widely recognized as the future for the aerospace industry to meet the power demands of increasing electric loads,reduce aircraft emissions,improve fuel economy,and lower the cost of the total system.展开更多
Accurate delineation of grape berry boundaries is essential for phenotypic measurement and growth assessment.This study proposes a multi-source feature fusion network(MFFNet)for instance segmentation of grape berries ...Accurate delineation of grape berry boundaries is essential for phenotypic measurement and growth assessment.This study proposes a multi-source feature fusion network(MFFNet)for instance segmentation of grape berries in dense clusters with frequent overlaps and blurred edges.MFFNet employs two parallel branches for feature extraction:a Swin Transformer backbone to capture hierarchical semantic features and an edge-detection branch that predicts an edge probability map to provide boundary cues.To address the substantial scale variation within a single image,the multilevel semantic features were enhanced using Adaptive Spatial Feature Fusion(ASFF).The edge probability map was introduced twice into the ASFFenhanced multi-scale features.First,edge cues were injected into the highest-resolution fused feature map to strengthen global boundary awareness across the cluster.Second,during mask generation,edge cues were reintroduced within each candidate instance region to refine local contours and improve the separation in the adhered areas.Experiments on a custom dataset collected in Yinchuan,Ningxia,showed that MFFNet achieved an mAP50boxof 93.4%and mAP50maskof 93.4%,outperforming representative baselines,including Mask2Former and HTC.The proposed model remained stable on images with severe berry overlap and indistinct edges,supporting practical grape growth monitoring.展开更多
Quantifying individual health status from increasingly accumulated omics data is essential for both early prevention and intervention of diseases,which attracts great attention from communities of biology and medicine...Quantifying individual health status from increasingly accumulated omics data is essential for both early prevention and intervention of diseases,which attracts great attention from communities of biology and medicine.Most of the existing approaches mainly classify individuals into different catalogues or classes based on phenotypes and biomarkers.However,an individual's health status from a dynamical systems viewpoint can be viewed as a non-equilibrium steady state,which can generally be characterized by two key features,i.e.(1)homeostatic potential that represents the ability of homeostatic resilience to withstand perturbations or maintain functions at the current state/phenotype of this individual and(2)phe-notypic potential that represents the state/phenotype of the individual on the whole process from health to disease.Here,we proposed a health state manifold(HSM)method derived from dynamic network biomarker method and diffusion map theory to quantify individual health status with the characterization of such two features in a robust and accurate manner based on multi-omics data.To verify our method,HSM method was applied to the quantification of diabetes mellitus(rat subjects)and the Roux-en-Y Gastric Bypass(human subjects)for both disease progression process and recovery process,which demonstrated its effectiveness and potential for personalized medicine and preventive medicine.展开更多
Large-scale renewable energy integration decreases the system inertia and restricts frequency regulation. To maintain the frequency stability, allocating adequate frequency-support sources poses a critical challenge t...Large-scale renewable energy integration decreases the system inertia and restricts frequency regulation. To maintain the frequency stability, allocating adequate frequency-support sources poses a critical challenge to planners. In this context, we propose a frequency-constrained coordination planning model of thermal units, wind farms, and battery energy storage systems (BESSs) to provide satisfactory frequency supports. Firstly, a modified multi-machine system frequency response (MSFR) model that accounts for the dynamic responses from both synchronous generators and grid-connected inverters is constructed with preset power-headroom. Secondly, the rate-of-change-of-frequency (ROCOF) and frequency response power are deduced to construct frequency constraints. A data-driven piecewise linearization (DDPWL) method based on hyperplane fitting and data classification is applied to linearize the highly nonlinear frequency response power. Thirdly, frequency constraints are inserted into our planning model, while the unit commitment based on the coordinated operation of the thermal-hydro-wind-BESS hybrid system is implemented. At last, the proposed model is applied to the IEEE RTS-79 test system. The results demonstrate the effectiveness of our co-planning model to keep the frequency stability.展开更多
In order to accurately predict the content and variation trend of dissolved gas in trans-former oil and guide the condition maintenance of power transformers,a combined prediction model based on multi-information fusi...In order to accurately predict the content and variation trend of dissolved gas in trans-former oil and guide the condition maintenance of power transformers,a combined prediction model based on multi-information fusion is proposed and its effectiveness is analysed.First of all,based on the possibility of pathological and missing historical sample data,a detection and filling method based on variable weight combination samples is established.Second,the authors propose two models.Aiming at the non-linear and non-stationary characteristics of gas content,a univariate decomposition prediction mode HBA-VMD-TCN which based on the Honey Badger algorithm,variational mode decomposition and time convolutional network(TCN)is established.Then the multi-variate Informer prediction model is established for gas content affected by multiple variables.Third,the cross-entropy theory is used to determine the weight coefficients of the two models,and the multi-information fusion combined prediction model is formed.Finally,on the basis of the above,a method to determine the time step and the position information of the transition point adaptively in the process of prediction is proposed to further improve the prediction accuracy.The results show that,through a series of simulation experiments of model comparison and transformer anomaly prediction,the accuracy and effectiveness of the combined prediction model are verified.展开更多
The common analytical models for the no-load iron loss of permanent magnet(PM)motors usually neglect the iron loss caused by the rotating magnetic field in the tooth tips and the harmonics of the magnetic fields in th...The common analytical models for the no-load iron loss of permanent magnet(PM)motors usually neglect the iron loss caused by the rotating magnetic field in the tooth tips and the harmonics of the magnetic fields in the teeth and yokes.This paper presents an analytical model for no-load iron loss of a fractional-slot surface-mounted permanent magnet motor.According to the existing analytical model of the magnetic field distribution in the slotted air gap,the magnetic flux densities considering the harmonics of the stator tooth and yoke are both derived based on the continuity of magnetic flux.Due to the complexity of the magnetic field in the tooth tip,the tangential flux density of the tooth tip is approximated by an equivalent sine wave and the radial component is regarded to be the same as that of the corresponding tooth.After obtaining the magnetic fields in stator different regions,the analytical iron loss is calculated by using the Bertotti model and the orthogonal decomposition model.A 20-pole/24-slot PM synchronous motor is taken as an example.The maximum error between the analytical model and finite element model(FEM)is 5.46%,which verifies the validity of the proposed method.展开更多
1.Introduction Electric vehicles(EVs)are playing an increasingly important role in decarbonizing the transportation sector.They constitute a promising solution to a set of global challenges such as climate change and ...1.Introduction Electric vehicles(EVs)are playing an increasingly important role in decarbonizing the transportation sector.They constitute a promising solution to a set of global challenges such as climate change and air pollution.EVs are an integration of a wide spectrum of techniques,such as battery monitoring,battery safety and vehicle energy management.In this regard,the EV development still faces significant challenges,which necessitate innovations in EV technologies.Given this,Green Energy and Intelligent Transportation(GEITS)organizes a special issue of“Key Technologies for Electric Vehicles”that attempts to advance knowledge in the area of EVs and provides a platform for researchers and engineers to share recent research results and discuss critical challenges in this field.A wide spectrum of topics are discussed,including but not limited to the following.展开更多
It is a worldwide challenge to achieve an efficient cleaning of heavy oil at ambient temperature.Conventional cleanup methods for high-viscosity oil spills exhibit low absorption efficiency and have severe practical o...It is a worldwide challenge to achieve an efficient cleaning of heavy oil at ambient temperature.Conventional cleanup methods for high-viscosity oil spills exhibit low absorption efficiency and have severe practical operating limits.Herein,inspired by the passive transport process in the Salvinia cucullata,a solar-heated and joule-heated textile-based absorber using the scalable electrostatic flocking technique.Benefiting from the efficient photothermal and electrothermal conversion effects,the textile-based absorber,with oleophilic and aligned channels,facilitates thermal conduction and hence enhances heavy oil absorption.The absorber is highly efficient for organic solvents(chloroform and dichloromethane)and low-viscosity oils(silicone oil,gasoline,and diesel oil).The surface temperature of the textile absorber rises rapidly to 92°C(114°C)in 120 s(240 s)under one sun irradiation(or 5 V voltage),resulting in a sharp drop in the viscosity of the heavy oil and then achieving an ultrahigh absorption rate(2647 kg h-1m-2)and fast equilibrium time(25 s).Rapid absorption rate significantly reduces spill cleanup time and spill spreading area,hence alleviating the environmental harm caused by oil spills as much as possible.The proposed solar-heated and joule-heated textile-based absorbers with aligned channels show great potential for efficient heavy oil absorption.展开更多
The successful market uptake of all-electric propulsion systems is closely related to the performance metrics of the electrical motor used within.In light of this,various road-maps have been set for the next two decad...The successful market uptake of all-electric propulsion systems is closely related to the performance metrics of the electrical motor used within.In light of this,various road-maps have been set for the next two decades by aerospace and automotive bodies targeting ambitious future targets of the motor's power densities and efficiencies.In achieving motors with such step-improvement performance metrics,often the thermal management is a key challenge.In this paper,a cooling structure for a propulsion motor of solar unmanned aircraft is proposed which combines the stator windings with heat pipes,and which is shown to simultaneously improve the heat dissipation as well as the efficiency.This paper firstly determines the heat transfer characteristic of the heat pipe experimentally which is then used in the development of a bespoke thermal network model of the motor.The effects of the cooling structure on the motor's temperature rise,copper losses,torque,and efficiency are studied in detail.Finally,a prototype is developed and a test platform is built.The experimental results are consistent with the analytical result,verifying the correctness of the thermal network model and the benefits of the proposed mechanism.Compared to the motor without heat pipes,the temperature rise of the motor is reduced by 35%,while its efficiency is improved by a significant 1.5%.展开更多
Skin,as the outmost layer of human body,is frequently exposed to environmental stressors including pollutants and ultraviolet(UV),which could lead to skin disorders.Generally,skin response process to ultraviolet B(UVB...Skin,as the outmost layer of human body,is frequently exposed to environmental stressors including pollutants and ultraviolet(UV),which could lead to skin disorders.Generally,skin response process to ultraviolet B(UVB)irradiation is a nonlinear dynamic process,with unknown underlying molecular mechanism of critical transition.Here,the landscape dynamic network biomarker(lDNB)analysis of time series transcriptome data on 3D skin model was conducted to reveal the complicated process of skin response to UV irradiation at both molecular and network levels.The advanced l-DNB analysis approach showed that:(i)there was a tipping point before critical transition state during pigmentation process,validated by 3D skin model;(ii)13 core DNB genes were identified to detect the tipping point as a network biomarker,supported by computational assessment;(iii)core DNB genes such as COL7A1 and CTNNB1 can effectively predict skin lightening,validated by independent human skin data.Overall,this study provides new insights for skin response to repetitive UVB irradiation,including dynamic pathway pattern,biphasic response,and DNBs for skin lightening change,and enables us to further understand the skin resilience process after external stress.展开更多
Obtaining continuous and high-quality soil moisture(SM) data is important in scientific research and applications,especially for agriculture, meteorology, and environmental monitoring. With the continuously increasing...Obtaining continuous and high-quality soil moisture(SM) data is important in scientific research and applications,especially for agriculture, meteorology, and environmental monitoring. With the continuously increasing number of artificial satellites in China, the acquisition of SM data from remote sensing images has received increasing attention.In this study, we constructed an SM inversion model by using a deep belief network(DBN) to extract SM data from Fengyun-3 D(FY-3 D) Medium Resolution Spectral Imager-Ⅱ(MERSI-Ⅱ) imagery;we named this model SM-DBN.The SM-DBN consists of two subnetworks: one for temperature and the other for SM. In the temperature subnetwork, bands 1, 2, 3, 4, 24, and 25 of the FY-3 D MERSI-Ⅱ imagery, which are relevant to temperature, were used as inputs while land surface temperatures(LST) obtained from ground stations were used as the expected output value when training the model. In the SM subnetwork, the input data included LSTs generated from the temperature subnetwork, normalized difference vegetation index(NDVI), and enhanced vegetation index(EVI);and the SM data obtained from ground stations were used as the expected outputs. We selected the Ningxia Hui Autonomous Region of China as the study area and used selected MERSI-Ⅱ images and in-situ observation station data from 2018 to 2019 to develop our dataset. The results of the SM-DBN were validated by using in-situ SM data as a reference, and its performance was also compared with those of the linear regression(LR) and back propagation(BP) neural network models. The overall accuracy of these models was measured by using the root mean square error(RMSE) of the differences between the model results and in-situ SM observation data. The RMSE of the LR, BP neural network, and SM-DBN models were 0.101, 0.083, and 0.032, respectively. These results suggest that the SM-DBN model significantly outperformed the other two models.展开更多
In the originally published version of this article(p.822),there was an error in the second affiliation of author Chengming Zhang.The erroneous affiliation was given as‘University of the Chinese Academy of Sciences’...In the originally published version of this article(p.822),there was an error in the second affiliation of author Chengming Zhang.The erroneous affiliation was given as‘University of the Chinese Academy of Sciences’.This has now been corrected to‘University of Chinese Academy of Sciences’.展开更多
Summary of main observation and conclusion Chloride is generally regarded as a harmful species for the heterogeneous catalysts, especially Au catalysts. In this work, a series of active Au/NiOx catalysts were successf...Summary of main observation and conclusion Chloride is generally regarded as a harmful species for the heterogeneous catalysts, especially Au catalysts. In this work, a series of active Au/NiOx catalysts were successfully prepared with co‐precipitation method by tracking the concentrations of chloride in the re‐dispersed aqueous solutions. For methyl esterification of alcohols, the highest active Au/NiOx catalysts could be prepared from aqueous solutions containing 8‐13 ppm chloride, the yield of methyl benzoate of catalyst Au/NiOx‐9 was 99%. The catalyst structures and the role of chloride in catalysts were explored by ICP, BET, XPS, TEM and EXAFS characterizations. It was found that the appropriate amount of residual chloride in Au catalysts was beneficial to their catalytic activities. Especially for Au/NiOx‐9, the appropriate amount of residual chloride had positive effects on the physicochemical properties of Au/NiOx catalyst, the position of Au nanoparticles (NPs) located on NiOx crystallites and the ratio of Au^δ+/Au^0 in catalyst, which together resulted in its high reactivity.展开更多
基金funded by the National Natural Science Foundation of China(NSFC)52003045National Natural Science Foundation of China(NSFC)52573058+3 种基金the Fundamental Research Funds for the Central Universities 2232023G-01the Shanghai Frontier Science Research Center for Modern Textiles,Shanghai Sailing Program 20YF1400700the Application Fundamental Projects of China National Textile and Apparel Council,the Shanghai Committee of Science and Technology,China(No.24ZR1400600)the Donghua University Discipline Innovation Field Cultivation Project,xkcx-202518.
摘要Interfacial solar-driven water evaporation offers a sustainable route to clean water production,but faces critical challenges of salt accumulation and organic contamination in complex industrial wastewater treatment.To address these challenges,we engineered a multifunctional 3D-printed hydrogel evaporator with vertically aligned grid architectures and hierarchical porosity.This unique structure promotes rapid water replenishment and Marangoni-driven salt back-diffusion through millimeter-scale channels,effectively preventing salt crystallization.By integrating carbon black and the metal-organic framework PCN-224 into the printing ink,we constructed a dual-functional photothermal-photocatalytic system.This synergistic combination not only enhances light absorption and photothermal conversion but also significantly reduces the water evaporation enthalpy.Coupled with heat-accelerated reaction kinetics,the system achieves efficient broad-spectrum photocatalytic degradation of organic pollutants.The resultant composite evaporator attains a high water evaporation rate of 2.04 kg m-2h-1under one-sun illumination,maintaining stable performance across a wide salinity range.Simultaneously,it degraded 96.5%of rhodamine B within 60 min under 1.5 kW m-2irradiation.
基金This work was supported by the National Key R&D Program of China(2021YFB2402002)the Beijing Natural Science Foundation(L223013)the Chongqing Automobile Collaborative Innovation Centre(No.2022CDJDX-004).
摘要Battery management systems(BMSs) play a vital role in ensuring efficient and reliable operations of lithium-ion batteries.The main function of the BMSs is to estimate battery states and diagnose battery health using battery open-circuit voltage(OCV).However,acquiring the complete OCV data online can be a challenging endeavor due to the time-consuming measurement process or the need for specific operating conditions required by OCV estimation models.In addressing these concerns,this study introduces a deep neural network-combined framework for accurate and robust OCV estimation,utilizing partial daily charging data.We incorporate a generative deep learning model to extract aging-related features from data and generate high-fidelity OCV curves.Correlation analysis is employed to identify the optimal partial charging data,optimizing the OCV estimation precision while preserving exceptional flexibility.The validation results,using data from nickel-cobalt-magnesium(NCM) batteries,illustrate the accurate estimation of the complete OCV-capacity curve,with an average root mean square errors(RMSE) of less than 3 mAh.Achieving this level of precision for OCV estimation requires only around 50 s collection of partial charging data.Further validations on diverse battery types operating under various conditions confirm the effectiveness of our proposed method.Additional cases of precise health diagnosis based on OCV highlight the significance of conducting online OCV estimation.Our method provides a flexible approach to achieve complete OCV estimation and holds promise for generalization to other tasks in BMSs.
摘要THE More Electric Aircraft(MEA)/All Electric Aircraft(AEA)system is being widely recognized as the future for the aerospace industry to meet the power demands of increasing electric loads,reduce aircraft emissions,improve fuel economy,and lower the cost of the total system.
基金funded by the Fengyun Satellite Application Pioneer Program(PhaseⅢ)(Grant No.FY-APP-2024.0301)the Science Foundation of Shandong(Grant No.ZR2021MD097)+1 种基金the Natural Science Foundation of Ningxia(Grant No.2024AAC03419)Shandong Provincial Meteorological Bureau Innovation Team Special Project(Grant No.2024sdcxtd04).
摘要Accurate delineation of grape berry boundaries is essential for phenotypic measurement and growth assessment.This study proposes a multi-source feature fusion network(MFFNet)for instance segmentation of grape berries in dense clusters with frequent overlaps and blurred edges.MFFNet employs two parallel branches for feature extraction:a Swin Transformer backbone to capture hierarchical semantic features and an edge-detection branch that predicts an edge probability map to provide boundary cues.To address the substantial scale variation within a single image,the multilevel semantic features were enhanced using Adaptive Spatial Feature Fusion(ASFF).The edge probability map was introduced twice into the ASFFenhanced multi-scale features.First,edge cues were injected into the highest-resolution fused feature map to strengthen global boundary awareness across the cluster.Second,during mask generation,edge cues were reintroduced within each candidate instance region to refine local contours and improve the separation in the adhered areas.Experiments on a custom dataset collected in Yinchuan,Ningxia,showed that MFFNet achieved an mAP50boxof 93.4%and mAP50maskof 93.4%,outperforming representative baselines,including Mask2Former and HTC.The proposed model remained stable on images with severe berry overlap and indistinct edges,supporting practical grape growth monitoring.
基金National Key Research and Development Program of China with Grant no.2022YFA1004800Shanghai Municipal Science and Technology Major Project with Grant no.23JS1401300+5 种基金Moonshot Research and Development Program with Grant no.JPMJMS2021The research funds of Hangzhou Institute for advanced study,UCAS with Grant no.Nos.2024HIAS-P004,2022ZZ01013Strategic Priority Research Program of the Chinese Academy of Sciences with Grant no.XDB38040400National Natural Science Foundation of China(NSFC)with Grant nos.12131020,31930022,T2341007,T2350003,42450135,42450084,12326614,12426310Natural Science Foundation of Zhejiang Province with Grant no.LZ22C060001The Zhejiang Province Vanguard Goose-Leading Initiative no.2025C01114.
摘要Quantifying individual health status from increasingly accumulated omics data is essential for both early prevention and intervention of diseases,which attracts great attention from communities of biology and medicine.Most of the existing approaches mainly classify individuals into different catalogues or classes based on phenotypes and biomarkers.However,an individual's health status from a dynamical systems viewpoint can be viewed as a non-equilibrium steady state,which can generally be characterized by two key features,i.e.(1)homeostatic potential that represents the ability of homeostatic resilience to withstand perturbations or maintain functions at the current state/phenotype of this individual and(2)phe-notypic potential that represents the state/phenotype of the individual on the whole process from health to disease.Here,we proposed a health state manifold(HSM)method derived from dynamic network biomarker method and diffusion map theory to quantify individual health status with the characterization of such two features in a robust and accurate manner based on multi-omics data.To verify our method,HSM method was applied to the quantification of diabetes mellitus(rat subjects)and the Roux-en-Y Gastric Bypass(human subjects)for both disease progression process and recovery process,which demonstrated its effectiveness and potential for personalized medicine and preventive medicine.
基金This work was supported by the National Key R&D Program of China (No. 2016YFB0900100)the National Natural Science Foundation of China (No. 51807116).
摘要Large-scale renewable energy integration decreases the system inertia and restricts frequency regulation. To maintain the frequency stability, allocating adequate frequency-support sources poses a critical challenge to planners. In this context, we propose a frequency-constrained coordination planning model of thermal units, wind farms, and battery energy storage systems (BESSs) to provide satisfactory frequency supports. Firstly, a modified multi-machine system frequency response (MSFR) model that accounts for the dynamic responses from both synchronous generators and grid-connected inverters is constructed with preset power-headroom. Secondly, the rate-of-change-of-frequency (ROCOF) and frequency response power are deduced to construct frequency constraints. A data-driven piecewise linearization (DDPWL) method based on hyperplane fitting and data classification is applied to linearize the highly nonlinear frequency response power. Thirdly, frequency constraints are inserted into our planning model, while the unit commitment based on the coordinated operation of the thermal-hydro-wind-BESS hybrid system is implemented. At last, the proposed model is applied to the IEEE RTS-79 test system. The results demonstrate the effectiveness of our co-planning model to keep the frequency stability.
基金National Natural Science Foundation of China,Grant/Award Number:51977179。
摘要In order to accurately predict the content and variation trend of dissolved gas in trans-former oil and guide the condition maintenance of power transformers,a combined prediction model based on multi-information fusion is proposed and its effectiveness is analysed.First of all,based on the possibility of pathological and missing historical sample data,a detection and filling method based on variable weight combination samples is established.Second,the authors propose two models.Aiming at the non-linear and non-stationary characteristics of gas content,a univariate decomposition prediction mode HBA-VMD-TCN which based on the Honey Badger algorithm,variational mode decomposition and time convolutional network(TCN)is established.Then the multi-variate Informer prediction model is established for gas content affected by multiple variables.Third,the cross-entropy theory is used to determine the weight coefficients of the two models,and the multi-information fusion combined prediction model is formed.Finally,on the basis of the above,a method to determine the time step and the position information of the transition point adaptively in the process of prediction is proposed to further improve the prediction accuracy.The results show that,through a series of simulation experiments of model comparison and transformer anomaly prediction,the accuracy and effectiveness of the combined prediction model are verified.
基金Supported by the Major Science and Technology Project Servo Drive and Motor Test Specification and Standard Research and Test Platform(2012ZX04001051).
摘要The common analytical models for the no-load iron loss of permanent magnet(PM)motors usually neglect the iron loss caused by the rotating magnetic field in the tooth tips and the harmonics of the magnetic fields in the teeth and yokes.This paper presents an analytical model for no-load iron loss of a fractional-slot surface-mounted permanent magnet motor.According to the existing analytical model of the magnetic field distribution in the slotted air gap,the magnetic flux densities considering the harmonics of the stator tooth and yoke are both derived based on the continuity of magnetic flux.Due to the complexity of the magnetic field in the tooth tip,the tangential flux density of the tooth tip is approximated by an equivalent sine wave and the radial component is regarded to be the same as that of the corresponding tooth.After obtaining the magnetic fields in stator different regions,the analytical iron loss is calculated by using the Bertotti model and the orthogonal decomposition model.A 20-pole/24-slot PM synchronous motor is taken as an example.The maximum error between the analytical model and finite element model(FEM)is 5.46%,which verifies the validity of the proposed method.
基金Beijing Natural Science Foundation(Grant No.L223013)National Natural Science Foundation of China(Grant No.52107222).
摘要1.Introduction Electric vehicles(EVs)are playing an increasingly important role in decarbonizing the transportation sector.They constitute a promising solution to a set of global challenges such as climate change and air pollution.EVs are an integration of a wide spectrum of techniques,such as battery monitoring,battery safety and vehicle energy management.In this regard,the EV development still faces significant challenges,which necessitate innovations in EV technologies.Given this,Green Energy and Intelligent Transportation(GEITS)organizes a special issue of“Key Technologies for Electric Vehicles”that attempts to advance knowledge in the area of EVs and provides a platform for researchers and engineers to share recent research results and discuss critical challenges in this field.A wide spectrum of topics are discussed,including but not limited to the following.
基金Acknowledgements Fundamental Research Funds for the Central Universities 2232023G-01,The project was funded by the National Natural Science Foundation of China(NSFC)52003045,Shanghai Frontier Science Research Center for Modern Textiles,Shanghai Sailing Program 20YF1400700,and the Application Fundamental Projects of China National Textile and Apparel Council.
摘要It is a worldwide challenge to achieve an efficient cleaning of heavy oil at ambient temperature.Conventional cleanup methods for high-viscosity oil spills exhibit low absorption efficiency and have severe practical operating limits.Herein,inspired by the passive transport process in the Salvinia cucullata,a solar-heated and joule-heated textile-based absorber using the scalable electrostatic flocking technique.Benefiting from the efficient photothermal and electrothermal conversion effects,the textile-based absorber,with oleophilic and aligned channels,facilitates thermal conduction and hence enhances heavy oil absorption.The absorber is highly efficient for organic solvents(chloroform and dichloromethane)and low-viscosity oils(silicone oil,gasoline,and diesel oil).The surface temperature of the textile absorber rises rapidly to 92°C(114°C)in 120 s(240 s)under one sun irradiation(or 5 V voltage),resulting in a sharp drop in the viscosity of the heavy oil and then achieving an ultrahigh absorption rate(2647 kg h-1m-2)and fast equilibrium time(25 s).Rapid absorption rate significantly reduces spill cleanup time and spill spreading area,hence alleviating the environmental harm caused by oil spills as much as possible.The proposed solar-heated and joule-heated textile-based absorbers with aligned channels show great potential for efficient heavy oil absorption.
基金the Natural Science Foundation for Outstanding Young Scholar[grant numbers 52122704]the National Natural Science Foundation of China[grant numbers U2141224 and 52077044].
摘要The successful market uptake of all-electric propulsion systems is closely related to the performance metrics of the electrical motor used within.In light of this,various road-maps have been set for the next two decades by aerospace and automotive bodies targeting ambitious future targets of the motor's power densities and efficiencies.In achieving motors with such step-improvement performance metrics,often the thermal management is a key challenge.In this paper,a cooling structure for a propulsion motor of solar unmanned aircraft is proposed which combines the stator windings with heat pipes,and which is shown to simultaneously improve the heat dissipation as well as the efficiency.This paper firstly determines the heat transfer characteristic of the heat pipe experimentally which is then used in the development of a bespoke thermal network model of the motor.The effects of the cooling structure on the motor's temperature rise,copper losses,torque,and efficiency are studied in detail.Finally,a prototype is developed and a test platform is built.The experimental results are consistent with the analytical result,verifying the correctness of the thermal network model and the benefits of the proposed mechanism.Compared to the motor without heat pipes,the temperature rise of the motor is reduced by 35%,while its efficiency is improved by a significant 1.5%.
基金partially supported by the National Natural Science Foundation of China(31930022,31771476,12026608,12042104,and 11871456)the Strategic Priority Project of CAS(XDB38040400)+1 种基金the National Key R&D Program of China(2017YFA0505500)JST Moonshot R&D program(JP MJMS2021 to L.C.).
摘要Skin,as the outmost layer of human body,is frequently exposed to environmental stressors including pollutants and ultraviolet(UV),which could lead to skin disorders.Generally,skin response process to ultraviolet B(UVB)irradiation is a nonlinear dynamic process,with unknown underlying molecular mechanism of critical transition.Here,the landscape dynamic network biomarker(lDNB)analysis of time series transcriptome data on 3D skin model was conducted to reveal the complicated process of skin response to UV irradiation at both molecular and network levels.The advanced l-DNB analysis approach showed that:(i)there was a tipping point before critical transition state during pigmentation process,validated by 3D skin model;(ii)13 core DNB genes were identified to detect the tipping point as a network biomarker,supported by computational assessment;(iii)core DNB genes such as COL7A1 and CTNNB1 can effectively predict skin lightening,validated by independent human skin data.Overall,this study provides new insights for skin response to repetitive UVB irradiation,including dynamic pathway pattern,biphasic response,and DNBs for skin lightening change,and enables us to further understand the skin resilience process after external stress.
基金Supported by the Science Foundation of Shandong(ZR2017MD018)Key Research and Development Program of Ningxia(2019BEH03008)+3 种基金Open Research Project of the Key Laboratory for Meteorological Disaster MonitoringEarly Warning and Risk Management of Characteristic Agriculture in Arid Regions(CAMF-201701 and CAMF-201803)Arid Meteorological Science Research Fund Project by the Key Open Laboratory of Arid Climate Change and Disaster Reduction of China Metrological Administration(IAM201801)Science Foundation of Ningxia(NZ12278)。
摘要Obtaining continuous and high-quality soil moisture(SM) data is important in scientific research and applications,especially for agriculture, meteorology, and environmental monitoring. With the continuously increasing number of artificial satellites in China, the acquisition of SM data from remote sensing images has received increasing attention.In this study, we constructed an SM inversion model by using a deep belief network(DBN) to extract SM data from Fengyun-3 D(FY-3 D) Medium Resolution Spectral Imager-Ⅱ(MERSI-Ⅱ) imagery;we named this model SM-DBN.The SM-DBN consists of two subnetworks: one for temperature and the other for SM. In the temperature subnetwork, bands 1, 2, 3, 4, 24, and 25 of the FY-3 D MERSI-Ⅱ imagery, which are relevant to temperature, were used as inputs while land surface temperatures(LST) obtained from ground stations were used as the expected output value when training the model. In the SM subnetwork, the input data included LSTs generated from the temperature subnetwork, normalized difference vegetation index(NDVI), and enhanced vegetation index(EVI);and the SM data obtained from ground stations were used as the expected outputs. We selected the Ningxia Hui Autonomous Region of China as the study area and used selected MERSI-Ⅱ images and in-situ observation station data from 2018 to 2019 to develop our dataset. The results of the SM-DBN were validated by using in-situ SM data as a reference, and its performance was also compared with those of the linear regression(LR) and back propagation(BP) neural network models. The overall accuracy of these models was measured by using the root mean square error(RMSE) of the differences between the model results and in-situ SM observation data. The RMSE of the LR, BP neural network, and SM-DBN models were 0.101, 0.083, and 0.032, respectively. These results suggest that the SM-DBN model significantly outperformed the other two models.
摘要In the originally published version of this article(p.822),there was an error in the second affiliation of author Chengming Zhang.The erroneous affiliation was given as‘University of the Chinese Academy of Sciences’.This has now been corrected to‘University of Chinese Academy of Sciences’.
摘要Summary of main observation and conclusion Chloride is generally regarded as a harmful species for the heterogeneous catalysts, especially Au catalysts. In this work, a series of active Au/NiOx catalysts were successfully prepared with co‐precipitation method by tracking the concentrations of chloride in the re‐dispersed aqueous solutions. For methyl esterification of alcohols, the highest active Au/NiOx catalysts could be prepared from aqueous solutions containing 8‐13 ppm chloride, the yield of methyl benzoate of catalyst Au/NiOx‐9 was 99%. The catalyst structures and the role of chloride in catalysts were explored by ICP, BET, XPS, TEM and EXAFS characterizations. It was found that the appropriate amount of residual chloride in Au catalysts was beneficial to their catalytic activities. Especially for Au/NiOx‐9, the appropriate amount of residual chloride had positive effects on the physicochemical properties of Au/NiOx catalyst, the position of Au nanoparticles (NPs) located on NiOx crystallites and the ratio of Au^δ+/Au^0 in catalyst, which together resulted in its high reactivity.