This paper deals with Mckean-Vlasov backward stochastic differential equations with weak monotonicity coefficients.We first establish the existence and uniqueness of solutions to Mckean-Vlasov backward stochastic diff...This paper deals with Mckean-Vlasov backward stochastic differential equations with weak monotonicity coefficients.We first establish the existence and uniqueness of solutions to Mckean-Vlasov backward stochastic differential equations.Then we obtain a comparison theorem in one-dimensional situation.展开更多
In this paper,we introduce the notion of G_(C)-X-injective modules,where X denotes a class of left S-modules and C represents a faithfully semidualizing bimodule.Under the condition that X satisfies certain hypotheses...In this paper,we introduce the notion of G_(C)-X-injective modules,where X denotes a class of left S-modules and C represents a faithfully semidualizing bimodule.Under the condition that X satisfies certain hypotheses,some properties and some equivalent characterizations of G_(C)-X-injective modules are investigated,and we also show that the triple(■,cores■,■)is a weak co-AB-context.As an application,two complete cotorsion pairs and a new model structure in Mod S are given.展开更多
Weak measurement offers a powerful framework for probing nonclassical features of quantum mechanics,with anomalous weak values serving as operational signatures of contextuality.While the anomalous weak value verifica...Weak measurement offers a powerful framework for probing nonclassical features of quantum mechanics,with anomalous weak values serving as operational signatures of contextuality.While the anomalous weak value verification of quantum contextuality has been predominantly investigated in the single-photon regime and analyzed under approximation condition of infinitesimally small perturbation strength.This study releases the approximation condition and takes into account the impact of perturbation strength on the rigor of the verification.And the investigation on the verification of contextuality is extended to the multi-photon scenarios for observing the influence of the correlation between photons on the verification.Without the limitation of infinitesimally small probability of disturbance,anomalous weak values are identified as necessary for contextuality to emerge,thereby refining the criterion proposed by Pusey[Phys.Rev.Lett.113200401(2014)].In the multi-photon scenarios,the emergence of contextuality also depends strongly on both the photon number and the photon-number distribution state.In particular,contextuality is found to be maximized when the single-photon component dominates and the second-order correlation is lower.These results highlight the critical role of photon statistics in experimental tests of contextuality via anomalous weak values.展开更多
Weakly Supervised Semantic Segmentation(WSSS),which relies only on image-level labels,has attracted significant attention for its cost-effectiveness and scalability.Existing methods mainly enhance inter-class distinct...Weakly Supervised Semantic Segmentation(WSSS),which relies only on image-level labels,has attracted significant attention for its cost-effectiveness and scalability.Existing methods mainly enhance inter-class distinctions and employ data augmentation to mitigate semantic ambiguity and reduce spurious activations.However,they often neglect the complex contextual dependencies among image patches,resulting in incomplete local representations and limited segmentation accuracy.To address these issues,we propose the Context Patch Fusion with Class Token Enhancement(CPF-CTE)framework,which exploits contextual relations among patches to enrich feature repre-sentations and improve segmentation.At its core,the Contextual-Fusion Bidirectional Long Short-Term Memory(CF-BiLSTM)module captures spatial dependencies between patches and enables bidirectional information flow,yield-ing a more comprehensive understanding of spatial correlations.This strengthens feature learning and segmentation robustness.Moreover,we introduce learnable class tokens that dynamically encode and refine class-specific semantics,enhancing discriminative capability.By effectively integrating spatial and semantic cues,CPF-CTE produces richer and more accurate representations of image content.Extensive experiments on PASCAL VOC 2012 and MS COCO 2014 validate that CPF-CTE consistently surpasses prior WSSS methods.展开更多
The 6D pose estimation of objects is of great significance for the intelligent assembly and sorting of industrial parts.In the industrial robot production scenarios,the 6D pose estimation of industrial parts mainly fa...The 6D pose estimation of objects is of great significance for the intelligent assembly and sorting of industrial parts.In the industrial robot production scenarios,the 6D pose estimation of industrial parts mainly faces two challenges:one is the loss of information and interference caused by occlusion and stacking in the sorting scenario,the other is the difficulty of feature extraction due to the weak texture of industrial parts.To address the above problems,this paper proposes an attention-based pixel-level voting network for 6D pose estimation of weakly textured industrial parts,namely CB-PVNet.On the one hand,the voting scheme can predict the keypoints of affected pixels,which improves the accuracy of keypoint localization even in scenarios such as weak texture and partial occlusion.On the other hand,the attention mechanism can extract interesting features of the object while suppressing useless features of surroundings.Extensive comparative experiments were conducted on both public datasets(including LINEMOD,Occlusion LINEMOD and T-LESS datasets)and self-made datasets.The experimental results indicate that the proposed network CB-PVNet can achieve accuracy of ADD(-s)comparable to state-of-the-art using only RGB images while ensuring real-time performance.Additionally,we also conducted robot grasping experiments in the real world.The balance between accuracy and computational efficiency makes the method well-suited for applications in industrial automation.展开更多
Adhesively bonded joints are widely used in modern lightweight structures due to their high strengthto-weight ratio and design flexibility.However,the reliable non-destructive evaluation of bond integrity remains a si...Adhesively bonded joints are widely used in modern lightweight structures due to their high strengthto-weight ratio and design flexibility.However,the reliable non-destructive evaluation of bond integrity remains a significant challenge.This study presents a numerical investigation of adhesively bonded joints with different adhesive properties using ultrasonic guided waves.The main focus of the investigation is to evaluate the feasibility of using guided waves to assess bond integrity,particularly for detecting challenging weak bonds.For this purpose,a theoretical analysis of dispersion curves was conducted,revealing that the S0 Lamb wave mode is significantly sensitive to variations in adhesive properties in the 300-700 kHz frequency range.Finite element modelling was used to analyse the propagation of guided waves in two scenarios:an adhesively bonded aluminum structure and a more complex configuration-adhesively bonded lap joints.The Short-Time Fourier Transform(STFT)was used to process the obtained results and determine the group velocities of guided waves.By analysing the group velocity characteristics,their dependence on the adhesive properties was identified.In the first scenario,a clear separation of S0 modes from A0 modes was observed in the STFT analysis,with a decrease in group velocity as adhesive stiffness increased.For the more complex lap joint scenario,the separation between A0 and S0 modes was less distinct.However,the analysis of the average group velocity shows a dependence of average group velocity on adhesive properties.This is similar to the first scenario.There is a decrease in average group velocity as adhesive stiffness increases.The results obtained demonstrate that guided wavebased methods have a high potential for non-destructive evaluation of adhesively bonded structures,including the detection of weak bonds.展开更多
Weakly supervised semantic segmentation(WSSS)is a tricky task,which only provides category information for segmentation prediction.Thus,the key stage of WSSS is to generate the pseudo labels.For convolutional neural n...Weakly supervised semantic segmentation(WSSS)is a tricky task,which only provides category information for segmentation prediction.Thus,the key stage of WSSS is to generate the pseudo labels.For convolutional neural network(CNN)based methods,in which class activation mapping(CAM)is proposed to obtain the pseudo labels,and only concentrates on the most discriminative parts.Recently,transformer-based methods utilize attention map from the multi-headed self-attention(MHSA)module to predict pseudo labels,which usually contain obvious background noise and incoherent object area.To solve the above problems,we use the Conformer as our backbone,which is a parallel network based on convolutional neural network(CNN)and Transformer.The two branches generate pseudo labels and refine them independently,and can effectively combine the advantages of CNN and Transformer.However,the parallel structure is not close enough in the information communication.Thus,parallel structure can result in poor details about pseudo labels,and the background noise still exists.To alleviate this problem,we propose enhancing convolution CAM(ECCAM)model,which have three improved modules based on enhancing convolution,including deeper stem(DStem),convolutional feed-forward network(CFFN)and feature coupling unit with convolution(FCUConv).The ECCAM could make Conformer have tighter interaction between CNN and Transformer branches.After experimental verification,the improved modules we propose can help the network perceive more local information from images,making the final segmentation results more refined.Compared with similar architecture,our modules greatly improve the semantic segmentation performance and achieve70.2%mean intersection over union(mIoU)on the PASCAL VOC 2012 dataset.展开更多
The deep tunnels are prone to mud and water inrush disasters when crossing water-rich weak zones.A good understanding the hydromechanical behavior of the water-rich weak zone in deep tunnels is the prerequisite for de...The deep tunnels are prone to mud and water inrush disasters when crossing water-rich weak zones.A good understanding the hydromechanical behavior of the water-rich weak zone in deep tunnels is the prerequisite for determining the limit support pressure on the tunnel face.However,the seepage forces within the water-rich weak zone are not well estimated in existing models.To overcome this,an analytical model is proposed in this study to determine the limit support pressure of a deep tunnel crossing the water-rich weak zone.The seepage force in the water-rich weak zone is obtained by solving a group of Laplace equations about the hydraulic head,avoiding complex physical and mathematical approximation in existing models.Besides,the seepage boundary conditions in the water-rich weak zone are considered at the nodes on the Neumann boundary and the Dirichlet boundary.The effectiveness of the proposed model is then validated by numerical simulations and engineering practice.It shows that the proposed model has higher accuracy and wider applicability in estimating the hydraulic head.The proposed model can be used for stability analysis of tunnel faces.展开更多
Tourism’s link to the Sustainable Development Goals has been a continuing emphasis,adding momentum to longstandingefforts to ensure tourism’s sustainability.Tourism transport is one of the largest sources of anthrop...Tourism’s link to the Sustainable Development Goals has been a continuing emphasis,adding momentum to longstandingefforts to ensure tourism’s sustainability.Tourism transport is one of the largest sources of anthropogenic carbonemissions,driving global ecological change with profound consequences for ecosystem functioning and biodiversity.Large-scale infrastructure projects such as railway expansion are increasingly promoted for their potential to reducetourism-related carbon dioxide emissions,yet their spatial ecological impacts on regional carbon cycles and ecosystemservices remain poorly understood.This study introduces the concept of Tourism Transport Ecological Efficiency(TTEE)to assess the relationship between human infrastructure,carbon emissions,and ecological sustainability.Using panel datafrom China’s railway expansion between 2011 and 2018,the study provides spatially explicit evidence of how transportinfrastructure shapes tourism’s ecological footprint.Results show that non-Eastern regions experienced a greater increasein TTEE(8.7%)compared to Eastern regions(5.5%),highlighting regional disparities in tourism transport ecologicalsustainability.Railway density had a significant positive direct effect on TTEE,particularly pronounced in non-Easternregions.Additionally,a significant indirect effect of railway density in nearby regions was identified.These findings revealthe interconnected ecological impacts of transport systems and underscore the importance of regionally targeted railwayinvestment strategies.By bridging infrastructure development with ecological processes,this study advances understandingof how tourism transport can be aligned with global carbon reduction goals and ecosystem protection.展开更多
We propose an optimization method based on evolutionary computation for the design of broadband high-efficiency current-biased reverse load-modulation power amplifiers(CB-RLM PAs).First,given the reverse load-modulati...We propose an optimization method based on evolutionary computation for the design of broadband high-efficiency current-biased reverse load-modulation power amplifiers(CB-RLM PAs).First,given the reverse load-modulation characteristics of CB-RLM PAs,a comprehensive objective function is proposed that combines multi-state impedance trajectory constraints with in-band performance deviations.For the saturation and 6 dB power back-off(PBO)states,approximately optimal impedance regions on the Smith chart are derived using impedance constraint circles based on load-pull simulations.These regions are used together with in-band performance deviations(e.g.,saturated efficiency,6 dB PBO efficiency,and saturated output power)for matching network optimization and design.Second,a multi-objective evolutionary algorithm based on decomposition with adaptive weights,neighborhood,and global replacement is integrated with harmonic balance simulations to optimize design parameters and evaluate performance.Finally,to validate the proposed method,a broadband CB-RLM PA operating from 0.6 to 1.8 GHz is designed and fabricated.Measurement results show that the efficiencies at saturation,6 dB PBO,and 8 dB PBO all exceed 43.6%,with saturated output power being maintained at 40.9–41.5 dBm,which confirms the feasibility and effectiveness of the proposed broadband high-efficiency CB-RLM PA optimization and design approach.展开更多
The weak and broken roof,explosive control and other problems seriously restrict the promotion of non coal pillar self-forming roadway technology.In order to solve such problems,a new method of non coal pillar self-fo...The weak and broken roof,explosive control and other problems seriously restrict the promotion of non coal pillar self-forming roadway technology.In order to solve such problems,a new method of non coal pillar self-forming roadway through non-blasting roof cutting and pressure relief was proposed in this study.A systematic research system of"theoretical analysis-physical experiment-engineering verification"was constructed with the 9103 working face of Longmenta Coal Mine as the research object.Firstly,the theoretical analysis was conducted to reveal the roof cutting mechanics mechanism of rock mass weakened by dense drilling,establish the design criteria for key drilling parameters,and obtain the key design parameters of dense drilling in the test working face.Secondly,the physical model test was conducted to make clear that the dense drilling method can directionally cut off the goaf roof along the set position,reducing the stress and deformation of the roadway surrounding rock.Finally,the field engineering tests were conducted,and monitoring results showed that the pressure relief effect of the dense drilling method was comparable to that of the directional blasting method,achieving non coal pillar self-forming roadway mining under non blasting conditions.展开更多
This study aims to explore how the Wei River Basin can enhance the efficiency of horizontal ecological compensation to promote high-quality and sustainable development in the Yellow River Basin.To achieve this,a four-...This study aims to explore how the Wei River Basin can enhance the efficiency of horizontal ecological compensation to promote high-quality and sustainable development in the Yellow River Basin.To achieve this,a four-stage DEA(Data Envelopment Analysis)method was employed to evaluate the efficiency of ecological compensation in six prefecture-level cities within the Wei River Basin from 2001 to 2022.In addition,the K-prototype clustering analysis method was integrated to assess the regional differences in ECE(ecological compensation efficiency).The findings indicate:(1)the ecological compensation efficiency in the upstream areas of the Wei River Basin is significantly higher than in the downstream regions;(2)the influence of factors such as the proportion of the tertiary industry,population density and residents’disposable income on the efficiency of ecological compensation is significant;(3)after excluding environmental factors,the overall ecological compensation efficiency showed a significant improvement.Based on these insights,it is recommended that the provinces of Shaanxi and Gansu further establish a robust compensation fund operation mechanism,build a cross-regional ecological compensation upstream-downstream coordination system,and strengthen inter-basin economic cooperation mechanisms to promote dual-driven development through technological advancement and scale benefits,thereby advancing ecological protection and sustainable development in the Wei River Basin.展开更多
Evaluating the effectivenes s of forest restoration projects is crucial for designing adaptive restoration strategies.However,existing studies have primarily focused on ecological outcomes while overlooking cost input...Evaluating the effectivenes s of forest restoration projects is crucial for designing adaptive restoration strategies.However,existing studies have primarily focused on ecological outcomes while overlooking cost inputs.This gap can lead to increased uncertainties in restoration planning.Here we investigated forest dynamics in China's Upper Yangtze River Basin(UYRB)using kernel Normalized Difference Vegetation Index(kNDVI),Leaf Area Index(LAI),Gross Primary Productivity(GPP),Ku-band Vegetation Optical Depth(Ku-VOD)time series and climate data from1982 to 2020.Subsequently,we employed a residual trend analysis integrating temporal effects to determine the relative contributions of climate change and human activities to forest dynamics before and after the implementation of forest restoration engineering in 1998.Additionally,we developed an Afforestation Efficiency Index(AEI)to quantitatively assess the cost efficiency of afforestation projects.Results indicated that forest in the UYRB showed sustained increases during 1982-2020,with most areas experiencing greater growth after 1998 than before.Temporal effects of climatic factors influenced over 42.7%of the forest,and incorporating time-lag and cumulative effects enhanced climate-based explanations of forest variations by 1.61-24.73%.Human activities emerged as the dominant driver of forest dynamics post 1998,whereas climate variables predominated before this period.The cost-effectiveness of forest restoration projects in the UYRB typically ranges from moderate to high,with higher success predominantly observed in the northeastern and eastern counties,while the central,western,and northwestern counties mainly showed relatively low efficiency.These findings stress the need for assessing forest restoration outcomes from both ecological and cost perspectives,and can offer valuable insights for optimizing the layout of forest restoration initiatives in the UYRB.展开更多
The goal of the present work is to demonstrate the potential of Artificial Neural Network(ANN)-driven Genetic Algorithm(GA)methods for energy efficiency and economic performance optimization of energy efficiency measu...The goal of the present work is to demonstrate the potential of Artificial Neural Network(ANN)-driven Genetic Algorithm(GA)methods for energy efficiency and economic performance optimization of energy efficiency measures in a multi-family house building in Greece.The energy efficiency measures include different heating/cooling systems(such as low-temperature and high-temperature heat pumps,natural gas boilers,split units),building envelope components for floor,walls,roof and windows of variable heat transfer coefficients,the installation of solar thermal collectors and PVs.The calculations of the building loads and investment and operating and maintenance costs of the measures are based on the methodology defined in Directive 2010/31/EU,while economic assumptions are based on EN 15459-1 standard.Typically,multi-objective optimization of energy efficiency measures often requires the simulation of very large numbers of cases involving numerous possible combinations,resulting in intense computational load.The results of the study indicate that ANN-driven GA methods can be used as an alternative,valuable tool for reliably predicting the optimal measures which minimize primary energy consumption and life cycle cost of the building with greatly reduced computational requirements.Through GA methods,the computational time needed for obtaining the optimal solutions is reduced by 96.4%-96.8%.展开更多
Weakly solvating electrolytes(WSEs)promote the formation of anion-driven solid electrolyte interphases(SEI),enabling stable lithium metal batteries.However,current strategies involving alkylated modification,steric hi...Weakly solvating electrolytes(WSEs)promote the formation of anion-driven solid electrolyte interphases(SEI),enabling stable lithium metal batteries.However,current strategies involving alkylated modification,steric hindrance incorporation,coordinated oxygen(O)regulation,and selective fluorination face poor-diversity interfacial chemistry,high cost,or environmental concerns.Here,we propose a heteroatom-substitution strategy to design a WSE composed of lithium bis(fluorosulfonyl)imide(LiFSI)and 1,4-oxathiane(OTA)as a single solvent.Substituting oxygen with sulfur in conventional 1,4-dioxane(1,4-DX)generates OTA with a modulated dipole and charge distribution,weakening Li^(+)-OTA coordination while promoting anion-involved solvation sheath.This unique solvation structure triggers the formation of an inorganic-rich SEI with sulfur-containing species,enabling high Li plating/stripping coulombic efficiency and stable Li‖Li symmetric cells cycling for 1000 h.Benefiting from the superior interfacial chemistry and wettability of the electrolyte to the LiFePO_(4) cathode,full cells exhibit exceptional cycling stability even at low negative-to-positive(N/P)ratios,A pouch cell coupled with3.58 mAh cm^(-2) LiFePO_(4) and 20μm Li(N/P~1.15)maintains 88.77%capacity after 150 cycles.This work shows a fluorine-free solvent design paradigm for advanced WSEs,providing novel insights toward stable LMBs.展开更多
Towards the development of highly efficient electrochromic coatings,the crystallinity,morphology(e.g.size and shape)of electrochromic nanomaterials,and their charge insertion capacities play a significant role.Herein,...Towards the development of highly efficient electrochromic coatings,the crystallinity,morphology(e.g.size and shape)of electrochromic nanomaterials,and their charge insertion capacities play a significant role.Herein,we report the structure-dependent colouration effciency in electrochromic coatings based on the use of 0D,1D and 2D tungsten trioxide(WO_(3))nanostructures.A series of WO_(3)with different nanostructures were prepared and used as working electrodes to fabricate electrochromic devices for smart windows applications.Facile spray coating was applied on fluorine-doped tin oxide(FTO)substrate to make~70%transparent working electrodes to investigate their charge insertion capacities,electrochromic active surface area,and colouration efficiency.Results showed that the 2D WO_(3)nanoflakes displayed the highest diffusion coefficient for the intercalation of 1.52×10^(-10)cm^(2)/s with an increased electrochemical active surface area of 25.10 mF/cm^(2),a large modulation of optical reflectance(42.63%)with 3.79 s shorter response time for bleaching and a greater colouration efficiency(CE)value(89.29 cm^(2)/C)at 700 nm compared to the CE value for 1D WO_(3)(of 22 cm^(2)/C)and 0D WO_(3)(8 cm^(2)/C).The outcome of this study provides a new insight and valuable contribution to design an efficient electrochromic coating by controlling and optimising the nanostructures of selective electrochromic materials.展开更多
This work is devoted to the study of initial boundary value problem for k-component system of semilinear wave equations with several fundamental boundary conditions(namely,the Dirichlet,Neumann,and Robin boundary cond...This work is devoted to the study of initial boundary value problem for k-component system of semilinear wave equations with several fundamental boundary conditions(namely,the Dirichlet,Neumann,and Robin boundary conditions).Blow-up results and lifespan estimates of solutions to the problem with two different types of weak damping terms and power nonlinearities in the sub-critical and critical cases on exterior domain are obtained.The test function technique is performed in the proofs.It is worth observing that our results in Theorem 1.1 in this article contain the results in[6]as a special case whenθ=0.To the best of our knowledge,the results in Theorems 1.1-1.2 are new.展开更多
In maize production,the development of density-tolerant and lodging-resistant varieties has made dense planting an effective strategy for achieving high and stable yields,with superior hybrids serving as a prerequisit...In maize production,the development of density-tolerant and lodging-resistant varieties has made dense planting an effective strategy for achieving high and stable yields,with superior hybrids serving as a prerequisite for successful highdensity cultivation.However,the photosynthetic mechanisms underlying improved density tolerance in maize hybrids released across different eras in China remain unclear.This study investigates 40 years of breeding progress toward enhanced photosynthetic traits under varying planting densities and elucidates the physiological and ecological bases of improved density tolerance in maize hybrids.A three-year field experiment was conducted from 2019 to 2021 to compare eight major Chinese hybrids from four decadal cohorts under three planting densities:45,000(D1),67,500(D2),and 90,000(D3)plants ha^(-1).At high density(D3),modern hybrids exhibited a more optimal canopy architecture and superior leaf photosynthetic performance compared to older hybrids,despite a slight reduction in specific leaf nitrogen.Notably,modern hybrids(2000s)were able to maintain higher net photosynthetic rates and photosynthetic nitrogen use efficiency(PNUE)at D3,resulting in the highest grain yield(GY),which was 118.47%greater than that of older hybrids(1970s).Leaf area duration after anthesis,total chlorophyll content,key photosynthetic enzyme activities,and maximum quantum efficiency of PSII photochemistry were all positively correlated with GY.Among these,PNUE showed the strongest correlation with grain yield and thus represents a key indicator for optimizing maize hybrids.Based on these findings,breeders should continue selecting hybrids under high-density and suboptimal conditions,focusing on optimizing population architecture and enhancing photosynthetic capacity while fine-tuning leaf nitrogen status to develop high-yielding,density-tolerant hybrids capable of sustaining long-term increases in maize grain yield.展开更多
Oil and gas pipelines are a vital long-distance liquid and natural gas carrier,but their functionality is being assessed from a two-fold perspective of power economy and environmentalism.This review concurs on the way...Oil and gas pipelines are a vital long-distance liquid and natural gas carrier,but their functionality is being assessed from a two-fold perspective of power economy and environmentalism.This review concurs on the way these outcomes are interdependent throughout the pipeline lifecycle by contending that the efficiency,emissions,reliability,and environmental risk are jointly determined through the shared design decisions,operating plans,integrity platforms,and monitoring and response plans.Our initial conceptualization is pipeline systems and performance measures,which are characterized by boundary and comparability issues of particular energy consumption,methane intensity,and release consequence measures.Next,we look at hydraulic and station optimization,focusing on the need to look at the importance of equipment performance at part loads,constraints consciousness dispatch,and transient management to prevent the erosion of integrity levels by efficiency gains.The integrity management is appraised as one of the key enablers of stewardship that connects the corrosion prevention,in-line inspection and verification,and the risk-based mitigation to less likely failure,less disruptive interventions,and reduced emissions during maintenance.We compare the leak and spill prevention,detection,quantification,and response of the SCADA(supervisory control and data acquisition)-based computational monitoring,distributed sensing,as well as aerial/satellite,focusing on the validation,characterization of uncertainty,and the operational parameters modulating the time-to-detect and isolation performance.Environmental impacts of the lifecycle,not related to releases,are explained,such as routing and construction disturbance,management of right-of-way,station externalities,decommissioning,and climate resilience.Lastly,we assess new technologies,such as continuous monitoring networks,electrification,superior materials,and multi-objective decision-making that collaborates to increase energy,reliability,and environmental performance in heterogeneous pipeline networks.展开更多
基金Supported by the National Natural Science Foundation of China(12001074)the Research Innovation Program of Graduate Students in Hunan Province(CX20220258)+1 种基金the Research Innovation Program of Graduate Students of Central South University(1053320214147)the Key Scientific Research Project of Higher Education Institutions in Henan Province(25B110025)。
文摘This paper deals with Mckean-Vlasov backward stochastic differential equations with weak monotonicity coefficients.We first establish the existence and uniqueness of solutions to Mckean-Vlasov backward stochastic differential equations.Then we obtain a comparison theorem in one-dimensional situation.
文摘In this paper,we introduce the notion of G_(C)-X-injective modules,where X denotes a class of left S-modules and C represents a faithfully semidualizing bimodule.Under the condition that X satisfies certain hypotheses,some properties and some equivalent characterizations of G_(C)-X-injective modules are investigated,and we also show that the triple(■,cores■,■)is a weak co-AB-context.As an application,two complete cotorsion pairs and a new model structure in Mod S are given.
基金Project supported by the National Natural Science Foun-dation of China(Grant Nos.62371199 and 62071186)the Natural Science Foundation of Guangdong Province,China(Grant No.2024A1515012427)+1 种基金the Quantum Science Strate-gic Initiative Project of Guangdong Province,China(Grant No.GDZX2305001)the Key Laboratory Project of Guangdong Province,China(Grant No.2020B1212060066).
文摘Weak measurement offers a powerful framework for probing nonclassical features of quantum mechanics,with anomalous weak values serving as operational signatures of contextuality.While the anomalous weak value verification of quantum contextuality has been predominantly investigated in the single-photon regime and analyzed under approximation condition of infinitesimally small perturbation strength.This study releases the approximation condition and takes into account the impact of perturbation strength on the rigor of the verification.And the investigation on the verification of contextuality is extended to the multi-photon scenarios for observing the influence of the correlation between photons on the verification.Without the limitation of infinitesimally small probability of disturbance,anomalous weak values are identified as necessary for contextuality to emerge,thereby refining the criterion proposed by Pusey[Phys.Rev.Lett.113200401(2014)].In the multi-photon scenarios,the emergence of contextuality also depends strongly on both the photon number and the photon-number distribution state.In particular,contextuality is found to be maximized when the single-photon component dominates and the second-order correlation is lower.These results highlight the critical role of photon statistics in experimental tests of contextuality via anomalous weak values.
文摘Weakly Supervised Semantic Segmentation(WSSS),which relies only on image-level labels,has attracted significant attention for its cost-effectiveness and scalability.Existing methods mainly enhance inter-class distinctions and employ data augmentation to mitigate semantic ambiguity and reduce spurious activations.However,they often neglect the complex contextual dependencies among image patches,resulting in incomplete local representations and limited segmentation accuracy.To address these issues,we propose the Context Patch Fusion with Class Token Enhancement(CPF-CTE)framework,which exploits contextual relations among patches to enrich feature repre-sentations and improve segmentation.At its core,the Contextual-Fusion Bidirectional Long Short-Term Memory(CF-BiLSTM)module captures spatial dependencies between patches and enables bidirectional information flow,yield-ing a more comprehensive understanding of spatial correlations.This strengthens feature learning and segmentation robustness.Moreover,we introduce learnable class tokens that dynamically encode and refine class-specific semantics,enhancing discriminative capability.By effectively integrating spatial and semantic cues,CPF-CTE produces richer and more accurate representations of image content.Extensive experiments on PASCAL VOC 2012 and MS COCO 2014 validate that CPF-CTE consistently surpasses prior WSSS methods.
基金supported by the Knowledge Innovation Program of Wuhan-Shuguang Project(Grant No.2023010201020443)the School-Level Scientific Research Project Funding Program of Jianghan University(Grant No.2022XKZX33)the Natural Science Foundation of Hubei Province(Grant No.2024AFB466).
文摘The 6D pose estimation of objects is of great significance for the intelligent assembly and sorting of industrial parts.In the industrial robot production scenarios,the 6D pose estimation of industrial parts mainly faces two challenges:one is the loss of information and interference caused by occlusion and stacking in the sorting scenario,the other is the difficulty of feature extraction due to the weak texture of industrial parts.To address the above problems,this paper proposes an attention-based pixel-level voting network for 6D pose estimation of weakly textured industrial parts,namely CB-PVNet.On the one hand,the voting scheme can predict the keypoints of affected pixels,which improves the accuracy of keypoint localization even in scenarios such as weak texture and partial occlusion.On the other hand,the attention mechanism can extract interesting features of the object while suppressing useless features of surroundings.Extensive comparative experiments were conducted on both public datasets(including LINEMOD,Occlusion LINEMOD and T-LESS datasets)and self-made datasets.The experimental results indicate that the proposed network CB-PVNet can achieve accuracy of ADD(-s)comparable to state-of-the-art using only RGB images while ensuring real-time performance.Additionally,we also conducted robot grasping experiments in the real world.The balance between accuracy and computational efficiency makes the method well-suited for applications in industrial automation.
基金supported by the Research Council of Lithuania(LMTLT),agreement no.S-MIP-22-5.
文摘Adhesively bonded joints are widely used in modern lightweight structures due to their high strengthto-weight ratio and design flexibility.However,the reliable non-destructive evaluation of bond integrity remains a significant challenge.This study presents a numerical investigation of adhesively bonded joints with different adhesive properties using ultrasonic guided waves.The main focus of the investigation is to evaluate the feasibility of using guided waves to assess bond integrity,particularly for detecting challenging weak bonds.For this purpose,a theoretical analysis of dispersion curves was conducted,revealing that the S0 Lamb wave mode is significantly sensitive to variations in adhesive properties in the 300-700 kHz frequency range.Finite element modelling was used to analyse the propagation of guided waves in two scenarios:an adhesively bonded aluminum structure and a more complex configuration-adhesively bonded lap joints.The Short-Time Fourier Transform(STFT)was used to process the obtained results and determine the group velocities of guided waves.By analysing the group velocity characteristics,their dependence on the adhesive properties was identified.In the first scenario,a clear separation of S0 modes from A0 modes was observed in the STFT analysis,with a decrease in group velocity as adhesive stiffness increased.For the more complex lap joint scenario,the separation between A0 and S0 modes was less distinct.However,the analysis of the average group velocity shows a dependence of average group velocity on adhesive properties.This is similar to the first scenario.There is a decrease in average group velocity as adhesive stiffness increases.The results obtained demonstrate that guided wavebased methods have a high potential for non-destructive evaluation of adhesively bonded structures,including the detection of weak bonds.
文摘Weakly supervised semantic segmentation(WSSS)is a tricky task,which only provides category information for segmentation prediction.Thus,the key stage of WSSS is to generate the pseudo labels.For convolutional neural network(CNN)based methods,in which class activation mapping(CAM)is proposed to obtain the pseudo labels,and only concentrates on the most discriminative parts.Recently,transformer-based methods utilize attention map from the multi-headed self-attention(MHSA)module to predict pseudo labels,which usually contain obvious background noise and incoherent object area.To solve the above problems,we use the Conformer as our backbone,which is a parallel network based on convolutional neural network(CNN)and Transformer.The two branches generate pseudo labels and refine them independently,and can effectively combine the advantages of CNN and Transformer.However,the parallel structure is not close enough in the information communication.Thus,parallel structure can result in poor details about pseudo labels,and the background noise still exists.To alleviate this problem,we propose enhancing convolution CAM(ECCAM)model,which have three improved modules based on enhancing convolution,including deeper stem(DStem),convolutional feed-forward network(CFFN)and feature coupling unit with convolution(FCUConv).The ECCAM could make Conformer have tighter interaction between CNN and Transformer branches.After experimental verification,the improved modules we propose can help the network perceive more local information from images,making the final segmentation results more refined.Compared with similar architecture,our modules greatly improve the semantic segmentation performance and achieve70.2%mean intersection over union(mIoU)on the PASCAL VOC 2012 dataset.
基金support from the National Natural Science Foun-dation of China(Grant Nos.U24A20599 and 42277173)the National Science and Technology Major Project of China(Grant No.2024ZD1004300)is gratefully acknowledged.
文摘The deep tunnels are prone to mud and water inrush disasters when crossing water-rich weak zones.A good understanding the hydromechanical behavior of the water-rich weak zone in deep tunnels is the prerequisite for determining the limit support pressure on the tunnel face.However,the seepage forces within the water-rich weak zone are not well estimated in existing models.To overcome this,an analytical model is proposed in this study to determine the limit support pressure of a deep tunnel crossing the water-rich weak zone.The seepage force in the water-rich weak zone is obtained by solving a group of Laplace equations about the hydraulic head,avoiding complex physical and mathematical approximation in existing models.Besides,the seepage boundary conditions in the water-rich weak zone are considered at the nodes on the Neumann boundary and the Dirichlet boundary.The effectiveness of the proposed model is then validated by numerical simulations and engineering practice.It shows that the proposed model has higher accuracy and wider applicability in estimating the hydraulic head.The proposed model can be used for stability analysis of tunnel faces.
文摘Tourism’s link to the Sustainable Development Goals has been a continuing emphasis,adding momentum to longstandingefforts to ensure tourism’s sustainability.Tourism transport is one of the largest sources of anthropogenic carbonemissions,driving global ecological change with profound consequences for ecosystem functioning and biodiversity.Large-scale infrastructure projects such as railway expansion are increasingly promoted for their potential to reducetourism-related carbon dioxide emissions,yet their spatial ecological impacts on regional carbon cycles and ecosystemservices remain poorly understood.This study introduces the concept of Tourism Transport Ecological Efficiency(TTEE)to assess the relationship between human infrastructure,carbon emissions,and ecological sustainability.Using panel datafrom China’s railway expansion between 2011 and 2018,the study provides spatially explicit evidence of how transportinfrastructure shapes tourism’s ecological footprint.Results show that non-Eastern regions experienced a greater increasein TTEE(8.7%)compared to Eastern regions(5.5%),highlighting regional disparities in tourism transport ecologicalsustainability.Railway density had a significant positive direct effect on TTEE,particularly pronounced in non-Easternregions.Additionally,a significant indirect effect of railway density in nearby regions was identified.These findings revealthe interconnected ecological impacts of transport systems and underscore the importance of regionally targeted railwayinvestment strategies.By bridging infrastructure development with ecological processes,this study advances understandingof how tourism transport can be aligned with global carbon reduction goals and ecosystem protection.
基金supported by the National Natural Science Foundation of China(Nos.62171204,62171129,62001192).
文摘We propose an optimization method based on evolutionary computation for the design of broadband high-efficiency current-biased reverse load-modulation power amplifiers(CB-RLM PAs).First,given the reverse load-modulation characteristics of CB-RLM PAs,a comprehensive objective function is proposed that combines multi-state impedance trajectory constraints with in-band performance deviations.For the saturation and 6 dB power back-off(PBO)states,approximately optimal impedance regions on the Smith chart are derived using impedance constraint circles based on load-pull simulations.These regions are used together with in-band performance deviations(e.g.,saturated efficiency,6 dB PBO efficiency,and saturated output power)for matching network optimization and design.Second,a multi-objective evolutionary algorithm based on decomposition with adaptive weights,neighborhood,and global replacement is integrated with harmonic balance simulations to optimize design parameters and evaluate performance.Finally,to validate the proposed method,a broadband CB-RLM PA operating from 0.6 to 1.8 GHz is designed and fabricated.Measurement results show that the efficiencies at saturation,6 dB PBO,and 8 dB PBO all exceed 43.6%,with saturated output power being maintained at 40.9–41.5 dBm,which confirms the feasibility and effectiveness of the proposed broadband high-efficiency CB-RLM PA optimization and design approach.
基金Project(2024YFC2909500)supported by the National Key Research and Development Program of ChinaProjects(42377148,52204164)supported by the National Natural Science Foundation of ChinaProject(2022XJSB03)supported by the Fundamental Research Funds for the Central Universities,China。
文摘The weak and broken roof,explosive control and other problems seriously restrict the promotion of non coal pillar self-forming roadway technology.In order to solve such problems,a new method of non coal pillar self-forming roadway through non-blasting roof cutting and pressure relief was proposed in this study.A systematic research system of"theoretical analysis-physical experiment-engineering verification"was constructed with the 9103 working face of Longmenta Coal Mine as the research object.Firstly,the theoretical analysis was conducted to reveal the roof cutting mechanics mechanism of rock mass weakened by dense drilling,establish the design criteria for key drilling parameters,and obtain the key design parameters of dense drilling in the test working face.Secondly,the physical model test was conducted to make clear that the dense drilling method can directionally cut off the goaf roof along the set position,reducing the stress and deformation of the roadway surrounding rock.Finally,the field engineering tests were conducted,and monitoring results showed that the pressure relief effect of the dense drilling method was comparable to that of the directional blasting method,achieving non coal pillar self-forming roadway mining under non blasting conditions.
基金funded by the Gansu Soft Science Planning Project(Grant No.25JRZA170).
文摘This study aims to explore how the Wei River Basin can enhance the efficiency of horizontal ecological compensation to promote high-quality and sustainable development in the Yellow River Basin.To achieve this,a four-stage DEA(Data Envelopment Analysis)method was employed to evaluate the efficiency of ecological compensation in six prefecture-level cities within the Wei River Basin from 2001 to 2022.In addition,the K-prototype clustering analysis method was integrated to assess the regional differences in ECE(ecological compensation efficiency).The findings indicate:(1)the ecological compensation efficiency in the upstream areas of the Wei River Basin is significantly higher than in the downstream regions;(2)the influence of factors such as the proportion of the tertiary industry,population density and residents’disposable income on the efficiency of ecological compensation is significant;(3)after excluding environmental factors,the overall ecological compensation efficiency showed a significant improvement.Based on these insights,it is recommended that the provinces of Shaanxi and Gansu further establish a robust compensation fund operation mechanism,build a cross-regional ecological compensation upstream-downstream coordination system,and strengthen inter-basin economic cooperation mechanisms to promote dual-driven development through technological advancement and scale benefits,thereby advancing ecological protection and sustainable development in the Wei River Basin.
基金supported by the National Natural Science Foundation of China(42071238)the Jiuzhaigou Post-Disaster Restoration and Reconstruction Program(5132202020000046)+1 种基金the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)the Ministry of Science and Technology of the People's Republic of China(2019QZKK0402)。
文摘Evaluating the effectivenes s of forest restoration projects is crucial for designing adaptive restoration strategies.However,existing studies have primarily focused on ecological outcomes while overlooking cost inputs.This gap can lead to increased uncertainties in restoration planning.Here we investigated forest dynamics in China's Upper Yangtze River Basin(UYRB)using kernel Normalized Difference Vegetation Index(kNDVI),Leaf Area Index(LAI),Gross Primary Productivity(GPP),Ku-band Vegetation Optical Depth(Ku-VOD)time series and climate data from1982 to 2020.Subsequently,we employed a residual trend analysis integrating temporal effects to determine the relative contributions of climate change and human activities to forest dynamics before and after the implementation of forest restoration engineering in 1998.Additionally,we developed an Afforestation Efficiency Index(AEI)to quantitatively assess the cost efficiency of afforestation projects.Results indicated that forest in the UYRB showed sustained increases during 1982-2020,with most areas experiencing greater growth after 1998 than before.Temporal effects of climatic factors influenced over 42.7%of the forest,and incorporating time-lag and cumulative effects enhanced climate-based explanations of forest variations by 1.61-24.73%.Human activities emerged as the dominant driver of forest dynamics post 1998,whereas climate variables predominated before this period.The cost-effectiveness of forest restoration projects in the UYRB typically ranges from moderate to high,with higher success predominantly observed in the northeastern and eastern counties,while the central,western,and northwestern counties mainly showed relatively low efficiency.These findings stress the need for assessing forest restoration outcomes from both ecological and cost perspectives,and can offer valuable insights for optimizing the layout of forest restoration initiatives in the UYRB.
文摘The goal of the present work is to demonstrate the potential of Artificial Neural Network(ANN)-driven Genetic Algorithm(GA)methods for energy efficiency and economic performance optimization of energy efficiency measures in a multi-family house building in Greece.The energy efficiency measures include different heating/cooling systems(such as low-temperature and high-temperature heat pumps,natural gas boilers,split units),building envelope components for floor,walls,roof and windows of variable heat transfer coefficients,the installation of solar thermal collectors and PVs.The calculations of the building loads and investment and operating and maintenance costs of the measures are based on the methodology defined in Directive 2010/31/EU,while economic assumptions are based on EN 15459-1 standard.Typically,multi-objective optimization of energy efficiency measures often requires the simulation of very large numbers of cases involving numerous possible combinations,resulting in intense computational load.The results of the study indicate that ANN-driven GA methods can be used as an alternative,valuable tool for reliably predicting the optimal measures which minimize primary energy consumption and life cycle cost of the building with greatly reduced computational requirements.Through GA methods,the computational time needed for obtaining the optimal solutions is reduced by 96.4%-96.8%.
基金the financial support from the National Natural Science Foundation of China,China(Grant Nos.52502258 and 52162030)the Yunnan Fundamental Research Projects,China(Grant Nos.202501AT070298,202401AU070163 and 202401AT070368)+5 种基金the Yunnan Engineering Research Center Innovation Ability Construction and Enhancement Projects,China(Grant No.2023-XMDJ-00617107)the Expert Workstation Support Project of Yunnan Province,China(Grant Nos.202405AF140069 and 202505AF350019)the University Service Key Industry Project of Yunnan Province,China(Grant No.FWCY-ZD2024005)the Shenzhen Science and Technology Program,China(Grant No.KJZD20230923114107014)the Scientific Research Foundation of Kunming University of Science and Technology,China(20220122)the Analysis and Test Foundation of Kunming University of Science and Technology,China(Grant No.2023T20220122)。
文摘Weakly solvating electrolytes(WSEs)promote the formation of anion-driven solid electrolyte interphases(SEI),enabling stable lithium metal batteries.However,current strategies involving alkylated modification,steric hindrance incorporation,coordinated oxygen(O)regulation,and selective fluorination face poor-diversity interfacial chemistry,high cost,or environmental concerns.Here,we propose a heteroatom-substitution strategy to design a WSE composed of lithium bis(fluorosulfonyl)imide(LiFSI)and 1,4-oxathiane(OTA)as a single solvent.Substituting oxygen with sulfur in conventional 1,4-dioxane(1,4-DX)generates OTA with a modulated dipole and charge distribution,weakening Li^(+)-OTA coordination while promoting anion-involved solvation sheath.This unique solvation structure triggers the formation of an inorganic-rich SEI with sulfur-containing species,enabling high Li plating/stripping coulombic efficiency and stable Li‖Li symmetric cells cycling for 1000 h.Benefiting from the superior interfacial chemistry and wettability of the electrolyte to the LiFePO_(4) cathode,full cells exhibit exceptional cycling stability even at low negative-to-positive(N/P)ratios,A pouch cell coupled with3.58 mAh cm^(-2) LiFePO_(4) and 20μm Li(N/P~1.15)maintains 88.77%capacity after 150 cycles.This work shows a fluorine-free solvent design paradigm for advanced WSEs,providing novel insights toward stable LMBs.
基金the funding by the ARC Research Hub for Advanced Manufacturing with 2D Materials(ARC IH210100025)。
文摘Towards the development of highly efficient electrochromic coatings,the crystallinity,morphology(e.g.size and shape)of electrochromic nanomaterials,and their charge insertion capacities play a significant role.Herein,we report the structure-dependent colouration effciency in electrochromic coatings based on the use of 0D,1D and 2D tungsten trioxide(WO_(3))nanostructures.A series of WO_(3)with different nanostructures were prepared and used as working electrodes to fabricate electrochromic devices for smart windows applications.Facile spray coating was applied on fluorine-doped tin oxide(FTO)substrate to make~70%transparent working electrodes to investigate their charge insertion capacities,electrochromic active surface area,and colouration efficiency.Results showed that the 2D WO_(3)nanoflakes displayed the highest diffusion coefficient for the intercalation of 1.52×10^(-10)cm^(2)/s with an increased electrochemical active surface area of 25.10 mF/cm^(2),a large modulation of optical reflectance(42.63%)with 3.79 s shorter response time for bleaching and a greater colouration efficiency(CE)value(89.29 cm^(2)/C)at 700 nm compared to the CE value for 1D WO_(3)(of 22 cm^(2)/C)and 0D WO_(3)(8 cm^(2)/C).The outcome of this study provides a new insight and valuable contribution to design an efficient electrochromic coating by controlling and optimising the nanostructures of selective electrochromic materials.
基金Supported by Fundamental Research Program of Shanxi Province(20210302123045,20210302123182)National Natural Science Foundation of China(11601446)。
文摘This work is devoted to the study of initial boundary value problem for k-component system of semilinear wave equations with several fundamental boundary conditions(namely,the Dirichlet,Neumann,and Robin boundary conditions).Blow-up results and lifespan estimates of solutions to the problem with two different types of weak damping terms and power nonlinearities in the sub-critical and critical cases on exterior domain are obtained.The test function technique is performed in the proofs.It is worth observing that our results in Theorem 1.1 in this article contain the results in[6]as a special case whenθ=0.To the best of our knowledge,the results in Theorems 1.1-1.2 are new.
基金supported by the National Natural Science Foundation of China(32071960)the National Key Research and Development Program of China(2018YFD0300603)。
文摘In maize production,the development of density-tolerant and lodging-resistant varieties has made dense planting an effective strategy for achieving high and stable yields,with superior hybrids serving as a prerequisite for successful highdensity cultivation.However,the photosynthetic mechanisms underlying improved density tolerance in maize hybrids released across different eras in China remain unclear.This study investigates 40 years of breeding progress toward enhanced photosynthetic traits under varying planting densities and elucidates the physiological and ecological bases of improved density tolerance in maize hybrids.A three-year field experiment was conducted from 2019 to 2021 to compare eight major Chinese hybrids from four decadal cohorts under three planting densities:45,000(D1),67,500(D2),and 90,000(D3)plants ha^(-1).At high density(D3),modern hybrids exhibited a more optimal canopy architecture and superior leaf photosynthetic performance compared to older hybrids,despite a slight reduction in specific leaf nitrogen.Notably,modern hybrids(2000s)were able to maintain higher net photosynthetic rates and photosynthetic nitrogen use efficiency(PNUE)at D3,resulting in the highest grain yield(GY),which was 118.47%greater than that of older hybrids(1970s).Leaf area duration after anthesis,total chlorophyll content,key photosynthetic enzyme activities,and maximum quantum efficiency of PSII photochemistry were all positively correlated with GY.Among these,PNUE showed the strongest correlation with grain yield and thus represents a key indicator for optimizing maize hybrids.Based on these findings,breeders should continue selecting hybrids under high-density and suboptimal conditions,focusing on optimizing population architecture and enhancing photosynthetic capacity while fine-tuning leaf nitrogen status to develop high-yielding,density-tolerant hybrids capable of sustaining long-term increases in maize grain yield.
文摘Oil and gas pipelines are a vital long-distance liquid and natural gas carrier,but their functionality is being assessed from a two-fold perspective of power economy and environmentalism.This review concurs on the way these outcomes are interdependent throughout the pipeline lifecycle by contending that the efficiency,emissions,reliability,and environmental risk are jointly determined through the shared design decisions,operating plans,integrity platforms,and monitoring and response plans.Our initial conceptualization is pipeline systems and performance measures,which are characterized by boundary and comparability issues of particular energy consumption,methane intensity,and release consequence measures.Next,we look at hydraulic and station optimization,focusing on the need to look at the importance of equipment performance at part loads,constraints consciousness dispatch,and transient management to prevent the erosion of integrity levels by efficiency gains.The integrity management is appraised as one of the key enablers of stewardship that connects the corrosion prevention,in-line inspection and verification,and the risk-based mitigation to less likely failure,less disruptive interventions,and reduced emissions during maintenance.We compare the leak and spill prevention,detection,quantification,and response of the SCADA(supervisory control and data acquisition)-based computational monitoring,distributed sensing,as well as aerial/satellite,focusing on the validation,characterization of uncertainty,and the operational parameters modulating the time-to-detect and isolation performance.Environmental impacts of the lifecycle,not related to releases,are explained,such as routing and construction disturbance,management of right-of-way,station externalities,decommissioning,and climate resilience.Lastly,we assess new technologies,such as continuous monitoring networks,electrification,superior materials,and multi-objective decision-making that collaborates to increase energy,reliability,and environmental performance in heterogeneous pipeline networks.