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Modeling of AC Losses in High-speed PMSM Windings:Methods,Challenges,and Prospects 被引量:1
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作者 Kaiwei He Wenxiang Zhao +1 位作者 Zhongze Wu Jinghua Ji 《CES Transactions on Electrical Machines and Systems》 2025年第2期163-176,共14页
High-speed permanent magnet synchronous motors(PMSMs)have recently been widely applied in various applications.However,due to the increased rotor speed and operating frequency increase,the winding AC losses rise subst... High-speed permanent magnet synchronous motors(PMSMs)have recently been widely applied in various applications.However,due to the increased rotor speed and operating frequency increase,the winding AC losses rise substantially,posing risks to the safety operation.Accurate modeling of the AC losses has therefore become critical at the motor initial design stage.This paper reviews the main modeling methods for AC copper losses in PMSMs,including analytical methods,finite element methods,and hybrid modeling methods.The advantages and disadvantages of each method are analyzed in detail,and key issues in the modeling process are discussed.Finally,future research directions in AC copper loss modeling are explored,providing new insights for motor design and performance optimization. 展开更多
关键词 Permanent magnet synchronous motor AC copper loss Motor windings High-speed motor
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Evaluation of plasma antioxidant activity in women with early pregnancy losses
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作者 Olga Gennadievna Tishkova Lydmila Vasilievna Dikareva +2 位作者 Nadezhda Titovna Berberova Maria Alexandrovna Polovinkina Victoria Pavlovna Osipova 《Journal of Biomedical Research》 2025年第6期651-654,共4页
Dear Editor,Early pregnancy loss is a condition whose relevance is determined not only by high incidence but also by the frequency of this pathology progressing into habitual miscarriage.According to the American Preg... Dear Editor,Early pregnancy loss is a condition whose relevance is determined not only by high incidence but also by the frequency of this pathology progressing into habitual miscarriage.According to the American Pregnancy Association,non-developing pregnancy(NDP),one of the forms of pregnancy loss,accounts for half of all miscarriages in the early stages[1]. 展开更多
关键词 habitual miscarriage pregnancy loss non developing pregnancy early pregnancy loss plasma antioxidant activity pregnancy lossaccounts
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An Optimization Method for Reducing Losses in Distribution Networks Based on Tabu Search Algorithm
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作者 Jiaqian Zhao Xiufang Gu +1 位作者 Xiaoyu Wei Mingyu Bao 《Journal of Electronic Research and Application》 2025年第2期181-190,共10页
With the continuous growth of power demand and the diversification of power consumption structure,the loss of distribution network has gradually become the focus of attention.Given the problems of single loss reductio... With the continuous growth of power demand and the diversification of power consumption structure,the loss of distribution network has gradually become the focus of attention.Given the problems of single loss reduction measure,lack of economy,and practicality in existing research,this paper proposes an optimization method of distribution network loss reduction based on tabu search algorithm and optimizes the combination and parameter configuration of loss reduction measure.The optimization model is developed with the goal of maximizing comprehensive benefits,incorporating both economic and environmental factors,and accounting for investment costs,including the loss of power reduction.Additionally,the model ensures that constraint conditions such as power flow equations,voltage deviations,and line transmission capacities are satisfied.The solution is obtained through a tabu search algorithm,which is well-suited for solving nonlinear problems with multiple constraints.Combined with the example of 10kV25 node construction,the simulation results show that the method can significantly reduce the network loss on the basis of ensuring the economy and environmental protection of the system,which provides a theoretical basis for distribution network planning. 展开更多
关键词 Distribution network loss reduction measures ECONOMY Optimization model Tabu search algorithm
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Mitigating voltage losses and strain in perovskite solar cells through precise microscopic arrangement of chemical monomers
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作者 Mei-Han Liu Xin-Xuan Yang +7 位作者 Le-Xin Wang Lin Fan Mao-Bin Wei Hui-Lian Liu Xiao-Yan Liu Jing-Hai Yang Feng-You Wang Li-Li Yang 《Rare Metals》 2025年第9期6199-6210,共12页
Organic-inorganic halide perovskite solar cells(PSCs)have attracted substantial attention as their superior photovoltaic performance.Nevertheless,due to the solution fabrication process,the distribution of the chemica... Organic-inorganic halide perovskite solar cells(PSCs)have attracted substantial attention as their superior photovoltaic performance.Nevertheless,due to the solution fabrication process,the distribution of the chemical monomer in the precursor is difficult to orderly control,culminating in the generation of stress and non-radiative recombination in the annealed films.This results in the degradation of open-circuit voltage(V_(oc))and power conversion efficiency(PCE)of the cells,deteriorating the stability of the PSCs.To address these challenges,we precisely control the microscopic arrangement of chemical monomers in the precursor and the crystallization kinetics of the films by introducing the 1,4-benzenedicarboximidamide dihydrochloride(TAD)molecule.The-C=N functional groups in the TAD can anchor on the[PbI_(6)]^(4-)monomers,and the distance between the two-C=N functional groups is slightly smaller than the Pb-Pb space of the[PbI_(6)]^(4-)monomers,promoting the dominance growth of the(001)plane.The approach effectively minimizes recombination loss from stress-induced defects,yielding a remarkably low voltage loss(V_(loss))of 0.32 V and offering a reliable method to overcome the detrimental strains in PSCs. 展开更多
关键词 Perovskite solar cells Structural properties Residual strain releasing Defect passivation Voltage loss
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The effect of a radial electric field on the neoclassical tearing mode driven losses of energetic trapped ions
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作者 Hugo E FERRARI Youwen SUN +2 位作者 Kaiyang HE Ricardo FARENGO Pablo L GARCÍA-MARTÍNEZ 《Plasma Science and Technology》 2025年第6期122-129,共8页
A rotating neoclassical tearing mode(NTM)can increase the trapped ion losses when the frequency of the NTM is close to the precessional frequency of the trapped particles.When an equilibrium electric field,produced by... A rotating neoclassical tearing mode(NTM)can increase the trapped ion losses when the frequency of the NTM is close to the precessional frequency of the trapped particles.When an equilibrium electric field,produced by the rotation of the plasma and the density gradient,is present,the average precessional frequency of the trapped ions changes and so does the mode frequency corresponding to the maximum loss rate.Our results show that when an electric field with a value of 11.2 kV/m at q=2 is included the maximum of the trapped ion losses increases from 27% to 30% based on EAST equilibrium. 展开更多
关键词 ion losses neoclassical tearing modes fast particles TOKAMAK plasma rotation radial electric field
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Changes in factor profiles deriving from photochemical losses of volatile organic compounds:Insight from daytime and nighttime positive matrix factorization ana
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作者 Baoshuang Liu Tao Yang +9 位作者 Sicong Kang Fuquan Wang Haixu Zhang Man Xu Wei Wang Jinrui Bai Shaojie Song Qili Dai Yinchang Feng Philip K.Hopke 《Journal of Environmental Sciences》 2025年第5期627-639,共13页
Substantial effects of photochemical reaction losses of volatile organic compounds(VOCs)on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data ... Substantial effects of photochemical reaction losses of volatile organic compounds(VOCs)on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data resolved profiles.Hourly speciated VOC data measured in Shijiazhuang,China from May to September 2021 were used to conduct study.The mean VOC concentration in the daytime and at nighttime were 32.8 and 36.0 ppbv,respectively.Alkanes and aromatics concentrations in the daytime(12.9 and 3.08 ppbv)were lower than nighttime(15.5 and 3.63 ppbv),whereas that of alkenes showed the opposite tendency.The concentration differences between daytime and nighttime for alkynes and halogenated hydrocarbonswere uniformly small.The reactivities of the dominant species in factor profiles for gasoline emissions,natural gas and diesel vehicles,and liquefied petroleum gas were relatively low and their profiles were less affected by photochemical losses.Photochemical losses produced a substantial impact on the profiles of solvent use,petrochemical industry emissions,combustion sources,and biogenic emissions where the dominant species in these factor profiles had high reactivities.Although the profile of biogenic emissions was substantially affected by photochemical loss of isoprene,the low emissions at nighttime also had an important impact on its profile.Chemical losses of highly active VOC species substantially reduced their concentrations in apportioned factor profiles.This study results were consistent with the analytical results obtained through initial concentration estimation,suggesting that the initial concentration estimation could be the most effective currently availablemethod for the source analyses of active VOCs although with uncertainty. 展开更多
关键词 Volatile organic compounds Dispersion normalization Photochemical loss Factor profile Positive matrix factorization
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Methodology for Detecting Non-Technical Energy Losses Using an Ensemble of Machine Learning Algorithms
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作者 Irbek Morgoev Roman Klyuev Angelika Morgoeva 《Computer Modeling in Engineering & Sciences》 2025年第5期1381-1399,共19页
Non-technical losses(NTL)of electric power are a serious problem for electric distribution companies.The solution determines the cost,stability,reliability,and quality of the supplied electricity.The widespread use of... Non-technical losses(NTL)of electric power are a serious problem for electric distribution companies.The solution determines the cost,stability,reliability,and quality of the supplied electricity.The widespread use of advanced metering infrastructure(AMI)and Smart Grid allows all participants in the distribution grid to store and track electricity consumption.During the research,a machine learning model is developed that allows analyzing and predicting the probability of NTL for each consumer of the distribution grid based on daily electricity consumption readings.This model is an ensemble meta-algorithm(stacking)that generalizes the algorithms of random forest,LightGBM,and a homogeneous ensemble of artificial neural networks.The best accuracy of the proposed meta-algorithm in comparison to basic classifiers is experimentally confirmed on the test sample.Such a model,due to good accuracy indicators(ROC-AUC-0.88),can be used as a methodological basis for a decision support system,the purpose of which is to form a sample of suspected NTL sources.The use of such a sample will allow the top management of electric distribution companies to increase the efficiency of raids by performers,making them targeted and accurate,which should contribute to the fight against NTL and the sustainable development of the electric power industry. 展开更多
关键词 Non-technical losses smart grid machine learning electricity theft FRAUD ensemble algorithm hybrid method forecasting classification supervised learning
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Model-Based Decentralized Dynamic Periodic Event-Triggered Control for Nonlinear Systems Subject to Packet Losses
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作者 Chengchao Li Xudong Zhao +2 位作者 Wei Xing Ning Xu Ning Zhao 《IEEE/CAA Journal of Automatica Sinica》 2025年第9期1908-1919,共12页
This paper studies the problem of designing a modelbased decentralized dynamic periodic event-triggering mechanism(DDPETM)for networked control systems(NCSs)subject to packet losses and external disturbances.Firstly,t... This paper studies the problem of designing a modelbased decentralized dynamic periodic event-triggering mechanism(DDPETM)for networked control systems(NCSs)subject to packet losses and external disturbances.Firstly,the entire NCSs,comprising the triggering mechanism,packet losses and output-based controller,are unified into a hybrid dynamical framework.Secondly,by introducing dynamic triggering variables,the DDPETM is designed to conserve network resources while guaranteeing desired performance properties and tolerating the maximum allowable number of successive packet losses.Thirdly,some stability conditions are derived using the Lyapunov approach.Differing from the zero-order-hold(ZOH)case,the model-based control sufficiently exploits the model information at the controller side.Between two updates,the controller predicts the plant state based on the models and received feedback information.With the model-based control,less transmission may be expected than with ZOH.Finally,numerical examples and comparative experiments demonstrate the effectiveness of the proposed method. 展开更多
关键词 Decentralized dynamic periodic event-triggering mechanism(DDPETM) hybrid system approach model-based control networked control system successive packet losses
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Author correction:Unraveling the efficiency losses and improving methods in quantum dotbased infrared up-conversion photodetectors
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作者 Jiao Jiao Liu Xinxin Yang +3 位作者 Qiulei Xu Ruiguang Chang Zhenghui Wu Huaibin Shen 《Opto-Electronic Science》 2025年第12期73-74,共2页
Correction to:Opto-Electronic Science https://www.oejournal.org/oes/article/doi/10.29026/oes.2024.230029 published online 21 March 2024.After the publication of this article1,it was brought to our attention that the i... Correction to:Opto-Electronic Science https://www.oejournal.org/oes/article/doi/10.29026/oes.2024.230029 published online 21 March 2024.After the publication of this article1,it was brought to our attention that the inset image and absorption spectrum in Fig.1(b)contained a mistake,probably leading to misunderstandings.The inset image and the absorption spectrum in Fig.1(b)were not based on the specific batch of PbS colloidal quantum dots(CQDs)used in this work. 展开更多
关键词 pbs colloidal quantum dots cqds used inset image quantum dots opto electronic science efficiency losses infrared up conversion absorption spectrum PHOTODETECTORS
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Cross-sectional analysis of hearing loss,age and tinnitus severity in a web-recruited cohort of 610 subjects
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作者 María Cuesta Pedro Cobo 《Journal of Otology》 2026年第1期38-49,共12页
Tinnitus:the hearing of a sound that has not been produced by any external or internal source,is a rather heterogeneous hearing disorder.Background/Objectives:Hearing loss has been shown to be the main risk factor for... Tinnitus:the hearing of a sound that has not been produced by any external or internal source,is a rather heterogeneous hearing disorder.Background/Objectives:Hearing loss has been shown to be the main risk factor for tinnitus while emotional disorders are risk factors for developing intrusive or bothersome tinnitus.Moreover,aging has also been identified as another risk factor.The aim of this paper was to analyse the correlation between hearing loss,age and tinnitus severity in a cohort of 610 tinnitus sufferers.Methods:Age,audiometric(hearing condition)and tinnitus(time duration and severity)data were assessed and analysed for all subjects just after recruiting(baseline).Furthermore,the average hearing loss(HL)curves of the participants for age groups were compared to these with the corresponding Age Related HL(ARHL).Results:For most of the age groups,the measured HL curves exceeded in 10-20 dB those of the ARHL.The average age of tinnitus onset(age minus tinnitus duration)was found to be 44-46 years in both men and women.Weak correlation between audiometric feature and tinnitus distress was observed.Conclusions:Hearing loss has been shown to be a clear risk factor for triggering tinnitus(86%of participants were hearing impaired).In this cohort,average measures of hearing loss showed,at most,weak associations with tinnitus-related distress,suggesting that non-audiological factors may play a predominant role. 展开更多
关键词 TINNITUS Age Hearing loss Tinnitus-related distress
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Neurobrucellosis:An Uncommon but Important Cause of Sensorineural Hearing Loss:a case report
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作者 Karim Messaoudi Walid Yacine Mohamed Cherif 《Journal of Otology》 2026年第1期22-26,共5页
Background:Brucellosis is a zoonotic infection common in Mediterranean countries and the Middle East.Neurological involvement,although rare,can lead to severe complications,including sensorineural hearing loss(SNHL).T... Background:Brucellosis is a zoonotic infection common in Mediterranean countries and the Middle East.Neurological involvement,although rare,can lead to severe complications,including sensorineural hearing loss(SNHL).This case is particularly noteworthy as it highlights irreversible auditory nerve damage in brucellosis,emphasizing the importance of early diagnosis and treatment to prevent permanent neurological consequences.The novelty of this case lies in the severity of auditory involvement despite timely treatment.Case Presentation:A 43-year-old male farmer of Maghrebi origin presented with neurobrucellosis complicated by severe,irreversible bilateral sensorineural hearing loss.The patient initially reported symptoms of hearing loss and dizziness,which were confirmed to be associated with auditory nerve involvement.Wright's serology and polymerase chain reaction(PCR)testing confirmed brucellosis.Despite appropriate and prolonged antibiotic therapy,including drugs that penetrate the meningeal barrier and act intracellularly,the patient's auditory impairment remained permanent.The patient is currently a candidate for cochlear implantation to manage his severe hearing loss.Neurological symptoms did not improve with treatment,but cochlear implantation may offer a potential solution to his hearing deficit.Conclusions:This case highlights the importance of early recognition and intervention in brucellosis cases,particularly those with neurological involvement.Delayed diagnosis and treatment can result in irreversible neurological damage.It also underscores the potential for cochlear implantation in patients with severe,irreversible sensorineural hearing loss caused by neurobrucellosis.Cochlear implantation offers an important solution for patients with brucellosis-related hearing deficits,improving their quality of life despite the neurological damage caused by the infection. 展开更多
关键词 BRUCELLOSIS ZOONOSIS Sensorineural hearing loss DIZZINESS
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Association of conventional chromosomal polymorphic variants in 580 couples with idiopathic recurrent pregnancy loss:A retrospective cohort study
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作者 Sunny Kumar Jignesh Kumar Patel Amit Roy Chowdhury +2 位作者 Shagufa Sheikh Purna Chandra Mahapatra Birendranath Banerjee 《Asian pacific Journal of Reproduction》 2026年第1期11-22,共12页
Objective:To investigate the potential link between chromosomal polymorphisms in couples who had a medical history of idiopathic recurrent pregnancy loss.Methods:Cytogenetic investigation was conducted with mitogen(Ph... Objective:To investigate the potential link between chromosomal polymorphisms in couples who had a medical history of idiopathic recurrent pregnancy loss.Methods:Cytogenetic investigation was conducted with mitogen(Phytohemagglutinin-M,Gibco)stimulated blood T lymphocytes by Giemsa trypsin Giemsa banding and Ag-NOR banding on 580 couples with a history of idiopathic recurrent pregnancy loss and 240 couples from the general population.Thirty good chromosomal spreads were captured,karyotyped,and analyzed.The karyotypes were designated using the International System for Human Cytogenomic Nomenclature 2024.Pearson Chi-square test was used to compare the frequency of chromosomal polymorphism variations in the idiopathic recurrent pregnancy loss group with the general population group.Results:A conventional cytogenetic investigation revealed that 45.43%of couples experiencing idiopathic recurrent pregnancy loss presented with various types of chromosomal polymorphic variants,compared to 11.88%in the general population.The overall frequency of these chromosomal polymorphic variants was significantly higher in the idiopathic recurrent pregnancy loss group compared to the general population group(OR 9.97,95%CI 6.99-14.21;P<0.05).Additionally,the prevalence of polymorphic variants was higher among males(49.14%)than females(41.72%)(P=0.01).Conclusions:Chromosomal polymorphic analysis may play a crucial role in the assessment and careful clinical management of cases with idiopathic recurrent pregnancy loss,especially when no other conclusive reasons are identified during the initial evaluation.Therefore,heteromorphism should not be overlooked while investigating the causes of idiopathic recurrent pregnancy loss. 展开更多
关键词 Polymorphic variants Chromosomal anomalies Repeated pregnancy loss Cytogenetic investigation
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A relay-based probabilistic prediction model for multi-fidelity scenarios in total pressure loss of a compressor cascade with micro-textured surfaces
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作者 Liyue WANG Cong WANG +2 位作者 Xinyue LAN Haochen ZHANG Gang SUN 《Chinese Journal of Aeronautics》 2026年第1期55-65,共11页
The micro-riblet structures have been demonstrated effective in controlling the Total Pressure Loss(TPL)of aero-engine blades.However,due to the considerable scale gap between micro-texture and an actual aero-engine b... The micro-riblet structures have been demonstrated effective in controlling the Total Pressure Loss(TPL)of aero-engine blades.However,due to the considerable scale gap between micro-texture and an actual aero-engine blade,wind tunnel tests and numerical simulations with massive grids directly describing the global flow field are costly for aerodynamic evaluation.Furthermore,the fine micro surface structure brings unavoidable manufacturing errors,and the probability prediction contributes to gaining the confidence interval of the results.Therefore,a novel relay-based probabilistic model for multi-fidelity scenarios in the TPL prediction of a compressor cascade with micro-riblet surfaces is proposed to trade off accuracy and efficiency.Combined with the low-fidelity flow data generated by an aerodynamic solution strategy using the boundary surrogate model and the high-fidelity flow data from the experiment,the relay-based modeling has been achieved through knowledge transferring,and the confidence interval can be provided by the Gaussian Process Regression(GPR)model.The TPL of compressor cascades with micro-riblet surfaces under different surface structures at March number Ma=0.64,0.74,0.84 have been evaluated using the Relay-Based Probabilistic(RBP)model.The results illustrate that the RBP model could provide higher accuracy than the Single-Fidelity-Data-Driven(SFDD)prediction model,which show the promising potential of multi-fidelity scenarios data fusion in the aerodynamic evaluation of multi-scale configurations. 展开更多
关键词 Knowledge transfer Micro-riblet Multi-fidelity surrogate Probability prediction model Total pressure loss
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Influence of long-term livestock manure substitution on water erosion and labile organic carbon lateral loss on subtropical sloping croplands
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作者 Keke Hua Bo Zhu +5 位作者 Zhibin Guo Daozhong Wang Linchuan Zhan Lin Jin Hirohiko Nagano Kazuyuki Inubushi 《Journal of Integrative Agriculture》 2026年第2期481-492,共12页
The lateral transport of labile organic carbon represents a critical pathway for soil organic carbon(SOC) loss,reducing organic carbon sequestration and increasing the risk of waterbody pollution.Livestock manure appl... The lateral transport of labile organic carbon represents a critical pathway for soil organic carbon(SOC) loss,reducing organic carbon sequestration and increasing the risk of waterbody pollution.Livestock manure application on croplands serves as a common fertilizer reduction practice to sustain crop yields,enhance SOC sequestration,and reduce water erosion.However,limited quantitative assessments have examined the effects of livestock manure substitution on labile organic carbon lateral loss and fluxes in long-term experiments.This study conducted a three-year field investigation on subtropical sloping croplands to assess the impact of livestock manure substitution on dissolved organic carbon(DOC) and particulate organic carbon(POC) loss via surface runoff,interflow and eroded sediments.There are four treatments:no fertilization(CK);chemical nitrogen fertilizer(SF),40% nitrogen substitution with pig manure(PMF),and 100% nitrogen substitution from pig manure(PM).Compared to SF treatment,long-term livestock manure substitution in PMF and PM treatments significantly(P<0.05) reduced annual cumulative surface runoff fluxes by 13.5 and 21.6%,respectively.Manure applications decreased annual sediment fluxes by 12.9 and 19.1%,respectively.Soil water stable aggregates for mean weight diameter(MWD) increased significantly by 37.7 and 73.6%.Annual cumulative POC loss flux via eroded sediment under PMF and PM treatments increased significantly(P<0.05) by 61.1 and 47.9%,respectively.The labile organic carbon loss fluxes,including DOC and POC losses,under PMF and PM treatments increased significantly(P<0.05) by 11.9 and 31.4%,respectively.These results demonstrate that while water erosion intensity decreases due to enhanced soil aggregate stability,the risk of labile organic carbon loss increases after long-term livestock manure substitution in subtropical sloping croplands.Future research should examine labile organic carbon lateral migration under various soil types and slope gradients for livestock manure application in subtropical agricultural ecosystem croplands to better understand extreme rainfall effects. 展开更多
关键词 hydrological carbon loss runoff and sediment organic manure sloping croplands
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Overexpression of OsCAX2 in indica rice reduces cadmium accumulation in grains without yield loss
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作者 Zhi Hu Wenli Zou +4 位作者 Huijing Ye Jie Ma Lijun Meng Jingguang Chen Guoyou Ye 《Journal of Integrative Agriculture》 2026年第1期390-393,共4页
Highlights OsCAX2 is localized to tonoplast,and cadmium induces its expression.OsCAX2 overexpression reduces cadmium concentration in indica rice grains by 49.1%.Cadmium(Cd)exposure poses significant health risks to h... Highlights OsCAX2 is localized to tonoplast,and cadmium induces its expression.OsCAX2 overexpression reduces cadmium concentration in indica rice grains by 49.1%.Cadmium(Cd)exposure poses significant health risks to humans,and the International Agency for Research on Cancer has classified it as a Group I carcinogen.Cadmium undergoes minimal metabolism in the human body;consequently,prolonged Cd^(2+)exposure can cause severe damage to multiple organs including the liver,kidneys,lungs,bones,and immune system(Shao et al.2024).Rice,one of the three global staple crops,and Cd exposure in humans primarily occurs the consumption of contaminated rice grains.The contribution of rice to the total dietary Cd intake is over 50% for non-smoking Asian populations(Chen et al.2018;Shi et al.2020). 展开更多
关键词 GRAIN cadmium accumulation yield loss cadmium concentration indica rice grains OscAX TONOPLAST cadmium induction
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Extreme Attitude Prediction of Amphibious Vehicles Based on Improved Transformer Model and Extreme Loss Function
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作者 Qinghuai Zhang Boru Jia +3 位作者 Zhengdao Zhu Jianhua Xiang Yue Liu Mengwei Li 《哈尔滨工程大学学报(英文版)》 2026年第1期228-238,共11页
Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instabili... Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instability,occur frequently in both experimental and operational data.This infrequency causes events to be overlooked by existing prediction models,which lack the precision to accurately predict inclination attitudes in amphibious vehicles.To address this gap in predicting attitudes near extreme inclination points,this study introduces a novel loss function,termed generalized extreme value loss.Subsequently,a deep learning model for improved waterborne attitude prediction,termed iInformer,was developed using a Transformer-based approach.During the embedding phase,a text prototype is created based on the vehicle’s operation log data is constructed to help the model better understand the vehicle’s operating environment.Data segmentation techniques are used to highlight local data variation features.Furthermore,to mitigate issues related to poor convergence and slow training speeds caused by the extreme value loss function,a teacher forcing mechanism is integrated into the model,enhancing its convergence capabilities.Experimental results validate the effectiveness of the proposed method,demonstrating its ability to handle data imbalance challenges.Specifically,the model achieves over a 60%improvement in root mean square error under extreme value conditions,with significant improvements observed across additional metrics. 展开更多
关键词 Amphibious vehicle Attitude prediction Extreme value loss function Enhanced transformer architecture External information embedding
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基于PolyLoss函数的不平衡犯罪隐语文本增强方法
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作者 李文邦 颜靖华 董泽 《数据与计算发展前沿(中英文)》 2026年第1期158-167,共10页
【目的】为解决犯罪隐语数据集存在的不平衡问题,进一步提升对犯罪隐语文本的分类效果。【方法】对于长文本,提出SimPoly方法;对于短文本,提出EDAPoly方法。【结果】实验结果表明,SimPoly和EDAPoly方法在解决犯罪隐语数据集不平衡问题... 【目的】为解决犯罪隐语数据集存在的不平衡问题,进一步提升对犯罪隐语文本的分类效果。【方法】对于长文本,提出SimPoly方法;对于短文本,提出EDAPoly方法。【结果】实验结果表明,SimPoly和EDAPoly方法在解决犯罪隐语数据集不平衡问题上显著提升了分类模型的表现,相较于未进行文本增强的基线方法,在准确率、召回率和F1分数等指标上均有明显提升。【结论】不仅为罪隐语识别技术的实际应用提供了一种有效的解决方案,也为类似的不平衡文本分类任务提供了新的思路和支持。 展开更多
关键词 犯罪隐语 文本增强 损失函数 不平衡文本处理
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Characteristics of Nitrogen and Phosphorus Losses in Different Crop Rotation Systems in the North of Erhai Lake Basin 被引量:9
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作者 汤秋香 任天志 +5 位作者 雷宝坤 翟丽梅 胡万里 张继宗 林涛 刘宏斌 《Agricultural Science & Technology》 CAS 2012年第10期2206-2212,共7页
[Objective] Nitrogen and phosphorus losses of surface runoff in various crop rotation systems in the north of Erhai Lake basin were studied with the objective to provide references for risk evaluation of environmental... [Objective] Nitrogen and phosphorus losses of surface runoff in various crop rotation systems in the north of Erhai Lake basin were studied with the objective to provide references for risk evaluation of environmental pollution and formulating countermeasures to control the nonpoint source pollution from agriculture.[Method] Water samples collected in four typical crop rotation systems distributed in seven towns(townships) in the north of Erhai Lake basin were investigated,as well as the fertilizer input,to explore the dynamic change of nitrogen and phosphorus content in surface water of farmland and ditch water,and the correlation between fertilizer input and the concentrations of nitrogen and phosphorus in the surface water of farmland and in the ditch water.[Result] The results showed that nitrogen loss in surface water of farmland in different crop rotation systems differed greatly,and the risk of nitrogen loss was 38% lower in broad bean-rice crop rotation than that in garlic-rice crop rotation.The water soluble nitrogen was the primary form of nitrogen loss.The content of water soluble nitrogen was significantly higher in garlic-rice crop rotation than that in the other rotation systems,and the concentrations of nitrogen in the surface water of farmland in different crop rotation systems followed the sequence below:garlic-rice crop rotationryegrass-rice crop rotationbroad bean-rice crop rotationrape-rice crop rotation.The loss of phosphorus in the surface water of farmland was relatively low and phosphorus combined with silt was the primary form for phosphorus loss.There was no significant difference of the loss of various forms of phosphorus in different crop rotation systems.The contents of total nitrogen and total phosphorus in the surface water of farmland were higher than that in ditch water,with increasing rates of total nitrogen and total phosphorus in ditch water of 72% and 82%,respectively.Topdressing was the critical reason for the high concentrations of nitrogen and phosphorus in the surface water,which also caused the increasing load to the ditch water.[Conclusion] Both the nitrogen and phosphorus loss were the highest in garlic-rice crop rotation.Reasonable crop rotation systems should be established based on both the environmental and economic benefits.This study provided references for controlling the nonpoint source pollution of farmland and improving the water quality of Erhai Lake. 展开更多
关键词 The northe areas of Erhai Lake basin FARMLAND Crop rotation Nitrogen and phosphorus losses
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Experimental study of an insert and its influence on churning losses in a high-speed electro-hydrostatic actuator pump of an aircraft 被引量:12
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作者 Junhui ZHANG Ying LI +2 位作者 Bing XU Min PAN Qun CHAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第8期2028-2036,共9页
The speed of an Electro-Hydrostatic Actuator(EHA) pump can recently reach 20000 r/min, and its churning losses increase obviously with an increasing speed, which results in low efficiency and thus increasing heat in a... The speed of an Electro-Hydrostatic Actuator(EHA) pump can recently reach 20000 r/min, and its churning losses increase obviously with an increasing speed, which results in low efficiency and thus increasing heat in aircraft EHA systems. In order to reduce churning losses at high speeds, more attention should be given to the design of an insert. In this paper, the effect of an insert with different design parameters on churning losses is investigated through Computational Fluid Dynamics(CFD) simulation and experiments by calculating the difference between churning losses torques of the test pump with and without the insert based on a high-speed churning losses test rig.Analytical results show that the gap between the insert and the cylinder is critical for churning losses reduction. It is found that the churning losses of the test pump can be reduced with a decreasing gap between the cylinder block and the insert at high speeds. This is because the insert can decrease the turbulence occurrence at high speeds. The results can be used for flow field analysis and optimization of the high-speed EHA pump and provide a new method for improving efficiency of high-speed EHA pumps. 展开更多
关键词 CHURNING losses Efficiency Electro-hydrostatic actuator PUMP High speed INSERT
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Resonance suppression and electromagnetic shielding effectiveness improvement of an apertured rectangular cavity by using wall losses 被引量:6
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作者 焦重庆 朱弘钊 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第8期404-409,共6页
The cavity-mode resonance effect could result in significant degradation of the shielding effectiveness (SE) of a shielding enclosure around its resonance frequencies. In this paper, the influence of coated wall los... The cavity-mode resonance effect could result in significant degradation of the shielding effectiveness (SE) of a shielding enclosure around its resonance frequencies. In this paper, the influence of coated wall loss on the suppression of the resonance effect is investigated. For this purpose, an equivalent circuit model is employed to analyze the SE of an apertured rectangular cavity coated with an inside layer of resistive material. The model is developed by extending Robinson's equivalent circuit model through incorporating the effect of the wall loss into both the propagation constant and the characteristic impedance of the waveguide. Calculation results show that the wall loss could lead to great improvement on the SE for frequencies near the resonance but almost no effect on the SE for frequencies far away from the resonance. 展开更多
关键词 electromagnetic shielding rectangular cavity wall losses resonance effect
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