Photocatalytic nitrogen fixation (PNF) is a promising alternative to the Haber-Bosch process.It achieves green ammonia production by utilizing solar energy for nitrogen fixation under mild conditions.While nanoscale p...Photocatalytic nitrogen fixation (PNF) is a promising alternative to the Haber-Bosch process.It achieves green ammonia production by utilizing solar energy for nitrogen fixation under mild conditions.While nanoscale photocatalysts offer enhanced performance due to their high surface area and abundant active sites,their small size makes them difficult to recover and prone to agglomeration.These bottlenecks severely limit industrial application.A promising solution is to immobilize the catalysts onto support surfaces.This paper provides a systematic review of recent advances in the design of immobilized photocatalysts for ammonia synthesis.It begins by outlining the key benefits of immobilization strategies,particularly in improving catalyst stability,recyclability,and overall photocatalytic performance.The working mechanisms and features of various immobilization techniques are then categorized and explained,covering physical adsorption/deposition,chemical bonding,in situ growth,and hybrid physico-chemical methods.Supported materials and common substrate types are also summarized.Furthermore,the widely used configurations of photoreactors suitable for immobilized systems are introduced.Finally,the review identifies current research limitations and challenges,and offers perspectives on future developments in the field of immobilized photocatalysis.展开更多
The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometr...The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometric distortions, leading to a diminution in the predictive accuracy of the distorted similitude. To address this challenge, this study formulates a novel set of scaling laws, tailored to account for the intricate geometric distortions associated with elastic rings. The proposed scaling laws are formulated based on the intrinsic deformation characteristics of elastic rings, rather than the traditional systemic governing equations. Numerical and experimental cases are conducted to assess the efficacy and precision of the proposed scaling laws, and the obtained results are compared with those achieved by traditional methods. The outcomes demonstrate that the scaling laws put forth by this study significantly enhance the predictive capabilities for deformations of elastic rings.展开更多
Aiming at the problem of dynamic instability of hard-brittle jointed rock surrounding in deep tunnel/roadway engineering,combining with the support concepts of"coupling rigidity with flexibility"and"ove...Aiming at the problem of dynamic instability of hard-brittle jointed rock surrounding in deep tunnel/roadway engineering,combining with the support concepts of"coupling rigidity with flexibility"and"overcoming rigidity by flexibility",the prevention and control method with"rigid-flexible coupling(R-F-C)"was put forward.Through numerical simulation calculation,the impact damage process,acoustic emission(AE)evolution characteristics,and element stress/displacement evolution characteristics of unsupported surrounding rock structure model,rigid supporting surrounding rock structure model,and"R-F-C"supporting surrounding rock structure model under horizontal bidirectional impact loading were compared and analyzed.Based on the theory of stress wave propagation,the dynamic instability catastrophe mechanism of three kinds of supporting structure models induced by horizontal bidirectional impact loading was revealed.Based on the Mohr-Coulomb strength theory,the stress discrimination methods of dynamic catastrophe of surrounding rock induced by horizontal bidirectional impact loading under three kinds of supporting structures were proposed.Combined with the above numerical simulation study,the explosion impact physical and mechanical test of"R-F-C"surrounding rock supporting plate structure was further designed and carried out.Finally,combined with the"conceptual model of ball-cliff potential energy instability",the energy driving theory and energy transformation mechanism of impact-induced rockburst under three kinds of supporting structures were discussed deeply.The research results provided a scientific basis for further promoting the effective application of"R-F-C"supporting structure in the prevention and control of dynamic instability of deep tunnel/roadway surrounding rock.展开更多
The primary goal of this study is to provide an efficient numerical tool to analyze the seismic performance of nailed walls.Modeling such excavation supports involves complexities due partly to the interaction of supp...The primary goal of this study is to provide an efficient numerical tool to analyze the seismic performance of nailed walls.Modeling such excavation supports involves complexities due partly to the interaction of support with soil and partly because of the amplification of seismic waves through an excavation wall.Consequently,innovative modeling is suggested herein,incorporating the calibration of the soil constitutive model in a targeted range of stress and strain,and the detection of a natural period of complex systems,including soil and structure,while benefiting from Rayleigh damping to filter unwanted noises.The numerical model was achieved by simulating a previous centrifuge test of the excavation wall,manifested at the pre-failure state.Notably,the calibration of the soil constitutive model through empirical relations,which replaces the numerical reproduction of an element test,more accurately simulated the soil-nail-wall interaction.Two factors were crucial to a successful result.First,probing the natural period of the complicated geometry of the model by applying white noises.Second,considering Rayleigh damping to withdraw unwanted noises and thus assess their permanent effects on the model.Rayleigh damping was applied instead of filtering the obtained results.展开更多
Autism spectrum disorder is a developmental disorder impacting a child’s social interactions,behaviors,and communication skills.One of the crucial aspects of autism care,which is often overlooked,is the parent’s men...Autism spectrum disorder is a developmental disorder impacting a child’s social interactions,behaviors,and communication skills.One of the crucial aspects of autism care,which is often overlooked,is the parent’s mental health status while trying to improve and overcome challenges faced by their child.A study by Lu et al examined the effectiveness of remote family psychological support courses on the mental health status of parents having children with autism spectrum disorder.It was found that the integration of these remote psychological courses with conventional care had a positive impact on the parents by reducing their stress levels,leading to an increase in their competence,and hence they could engage effectively in child therapy.However,a long-term study is necessary to assess whether these interventions have a sustained effect.The study emphasizes the need for developing such culturally sensitive intervention models on a global scale,making them accessible to all and improving autism care support.展开更多
To study the influence of support timing and support strength on the mechanical properties and deformation damage characteristics of a single-sided unloaded rock mass,a true triaxial perturbation unloaded rock testing...To study the influence of support timing and support strength on the mechanical properties and deformation damage characteristics of a single-sided unloaded rock mass,a true triaxial perturbation unloaded rock testing system was used to conduct rock damage tests on sandstone with different support timing and strength paths.Based on the acoustic emission monitoring system,the spatial and temporal evolution characteristics of the whole process of rock body loaded instability under two stress paths were studied,and the mechanism of the reinforcing effect of stress support on the unloaded rock mass was analyzed.The results show that,within the scope of this study,both earlier applications of shoring and an increase in shoring strength can effectively improve the ultimate bearing capacity of the unloaded rock,which increases the ultimate bearing capacity of the unloaded rock mass by 60.31% and 54.96%,respectively;There is a phenomenon of rebound deformation of the rock mass during sudden changes in stress(single-sided unloading,stress support),which shows opposite expansion and compression platforms on the stress−strain curve;The crack evolution of unloaded rock under different stress support conditions shows the state law of"initial crack activation→middle steady state expansion→late main crack penetration",and the lagging support significantly accelerates the crack evolution from local activation to main penetration;The single-sided unloading and stress-supporting stages have less influence on the unloading deformationsσ_(1u),σ_(2u) and support deformationsσ_(1) t,σ_(2t) in theσ_(1) andσ_(2)directions,while they show significant response characteristics toσ_(3u),σ_(vu) and σ_(3) t,σ_(vt),and with the increase of the support strength,the stress-supporting stagesσ_(3) t,σ_(vt) gradually increase and exceed the deformations generated by the unloading stagesσ_(3u),σ_(vu);The increase of support strength can effectively compensate for the rock stress loss caused by unloading,which makes the maximum,minimum,and volumetric strain support coefficients during the loading and unloading of the rock body increase gradually while the effect on the intermediate principal strain support coefficient is small;During loading,the support strength of rock masses seeks a new bearing area by regulating stress equilibrium states.This process primarily manifests as a shift in the locations of the crushing zone and the main bearing area,accompanied by a corresponding transformation in failure patterns.Consequently,the rock mass transitions from asymmetric three-zone damage under no or weak support to approximate symmetric three-zone damage under strong support.Simultaneously,the main load-bearing area of the rock mass shifts from deep bearing in the unsupported to middle bearing under strong support as the support strength increases.展开更多
Modern intelligent systems,such as autonomous vehicles and face recognition,must continuously adapt to new scenarios while preserving their ability to handle previously encountered situations.However,when neural netwo...Modern intelligent systems,such as autonomous vehicles and face recognition,must continuously adapt to new scenarios while preserving their ability to handle previously encountered situations.However,when neural networks learn new classes sequentially,they suffer from catastrophic forgetting—the tendency to lose knowledge of earlier classes.This challenge,which lies at the core of class-incremental learning,severely limits the deployment of continual learning systems in real-world applications with streaming data.Existing approaches,including rehearsalbased methods and knowledge distillation techniques,have attempted to address this issue but often struggle to effectively preserve decision boundaries and discriminative features under limited memory constraints.To overcome these limitations,we propose a support vector-guided framework for class-incremental learning.The framework integrates an enhanced feature extractor with a Support Vector Machine classifier,which generates boundary-critical support vectors to guide both replay and distillation.Building on this architecture,we design a joint feature retention strategy that combines boundary proximity with feature diversity,and a Support Vector Distillation Loss that enforces dual alignment in decision and semantic spaces.In addition,triple attention modules are incorporated into the feature extractor to enhance representation power.Extensive experiments on CIFAR-100 and Tiny-ImageNet demonstrate effective improvements.On CIFAR-100 and Tiny-ImageNet with 5 tasks,our method achieves 71.68%and 58.61%average accuracy,outperforming strong baselines by 3.34%and 2.05%.These advantages are consistently observed across different task splits,highlighting the robustness and generalization of the proposed approach.Beyond benchmark evaluations,the framework also shows potential in few-shot and resource-constrained applications such as edge computing and mobile robotics.展开更多
The neutral surface of a concave thin mirror is too close to the mirror surface,which makes it difficult to effectively mount the flexible structure and increases the mirror surface shape error.To address this problem...The neutral surface of a concave thin mirror is too close to the mirror surface,which makes it difficult to effectively mount the flexible structure and increases the mirror surface shape error.To address this problem,we design a flexible support structure including connectors,a support plate,and flexible structures,and construct an equivalent mirror by installing connectors and a support plate on the back of the mirror.While ensuring that the neutral surface of the equivalent mirror is moved away from the mirror surface,we optimize the support structure so that the rotary center of the flexible structure is located on the neutral surface of the equivalent mirror,avoiding the tilting moment.Following design and modeling of the structure,we analyze the static and dynamic characteristics using a finite element simulation,finding a root-mean-square(RMS)value for the surface shape error of 9.28 nm under the coupled effects of 1g gravity load,4℃ temperature rise,and 0.005 mm unevenness assembly error,with a fundamental frequency of 170.75 Hz,which all meet the design requirements.Finally,we carry out a surface shape error test of the mirror assembly,confirming it to meet the design index requirement of the mirror assembly.Simulation and test results verify the reliability and effectiveness of our proposed support structure.展开更多
Objective:To explore the clinical effect of personalized nutritional support in elderly women with gestational diabetes(GDM),and explore its impact on the incidence of maternal complications and pregnancy outcomes.Met...Objective:To explore the clinical effect of personalized nutritional support in elderly women with gestational diabetes(GDM),and explore its impact on the incidence of maternal complications and pregnancy outcomes.Methods:A total of 90 elderly pregnant women with gestational diabetes who were delivered in our hospital from January 2023 to January 2024 were selected as the research objects.They were randomly divided into an observation group and a control group,with 45 cases in each group.The control group only received routine pregnancy care and basic nutrition guidance,while the observation group received personalized nutrition support on this basis.Compare the blood glucose control,incidence of pregnancy complications,pregnancy outcomes,and neonatal outcomes between two groups of parturient.Result:After intervention,the fasting blood glucose(FPG),2-hour postprandial blood glucose(2hPG),and glycated hemoglobin(HbA1c)of the observation group were significantly lower than those of the control group,and the differences were statistically significant(p<0.05);The incidence of complications such as gestational hypertension syndrome,polyhydramnios,premature rupture of membranes,and postpartum hemorrhage in the observation group was significantly lower than that in the control group,and the difference was statistically significant(p<0.05);The cesarean section rate in the observation group was significantly lower than that in the control group,and the incidence of adverse neonatal outcomes such as fetal distress,macrosomia,neonatal asphyxia,and neonatal hypoglycemia in the observation group was significantly lower than that in the control group,with statistical significance(p<0.05).Conclusion:Individualized nutritional support for elderly women with gestational diabetes can effectively improve the level of maternal blood sugar control,reduce the incidence of complications during pregnancy,and improve the outcome of pregnancy and neonatal outcomes,which is of high clinical value.展开更多
The advantages of genome selection(GS) in animal and plant breeding are self-evident.Traditional parametric models have disadvantage in better fit the increasingly large sequencing data and capture complex effects acc...The advantages of genome selection(GS) in animal and plant breeding are self-evident.Traditional parametric models have disadvantage in better fit the increasingly large sequencing data and capture complex effects accurately.Machine learning models have demonstrated remarkable potential in addressing these challenges.In this study,we introduced the concept of mixed kernel functions to explore the performance of support vector machine regression(SVR) in GS.Six single kernel functions(SVR_L,SVR_C,SVR_G,SVR_P,SVR_S,SVR_L) and four mixed kernel functions(SVR_GS,SVR_GP,SVR_LS,SVR_LP) were used to predict genome breeding values.The prediction accuracy,mean squared error(MSE) and mean absolute error(MAE) were used as evaluation indicators to compare with two traditional parametric models(GBLUP,BayesB) and two popular machine learning models(RF,KcRR).The results indicate that in most cases,the performance of the mixed kernel function model significantly outperforms that of GBLUP,BayesB and single kernel function.For instance,for T1 in the pig dataset,the predictive accuracy of SVR_GS is improved by 10% compared to GBLUP,and by approximately 4.4 and 18.6% compared to SVR_G and SVR_S respectively.For E1 in the wheat dataset,SVR_GS achieves 13.3% higher prediction accuracy than GBLUP.Among single kernel functions,the Laplacian and Gaussian kernel functions yield similar results,with the Gaussian kernel function performing better.The mixed kernel function notably reduces the MSE and MAE when compared to all single kernel functions.Furthermore,regarding runtime,SVR_GS and SVR_GP mixed kernel functions run approximately three times faster than GBLUP in the pig dataset,with only a slight increase in runtime compared to the single kernel function model.In summary,the mixed kernel function model of SVR demonstrates speed and accuracy competitiveness,and the model such as SVR_GS has important application potential for GS.展开更多
This study investigated the effects of parental involvement,parenting stress,and social support on the social skills of school-aged children(6-18 years old)with intellectual disabilities(ID).Data were collected from 2...This study investigated the effects of parental involvement,parenting stress,and social support on the social skills of school-aged children(6-18 years old)with intellectual disabilities(ID).Data were collected from 280 Chinese parents(mothers=70.0%,fathers=30.0%)of children with ID through purposive sampling and analyzed using partial least squares structural equation modeling(PLS-SEM).The results indicated that parental involvement not only directly enhanced children’s social skills but also indirectly improved them by alleviating parenting stress,which acted as a partial mediator.Contrary to the stress-buffering hypothesis,social support did not moderate the negative impact of parenting stress on social skills.Theoretically,this study contributes by validating ecological systems theory through a shift in focus from individual deficits to family systems,while also challenging the conventional view of stress-buffering theory.Accordingly,parent-support programs should integrate practical involvement training with systematic stress reduction and provide tailored assistance such as behavior-management training and respite care.展开更多
In-situ enlargement of super-large-span tunnels can intensify excavation-induced unloading in the surrounding rock,increasing deformation demand and failure risk during construction.This study combines laboratory mode...In-situ enlargement of super-large-span tunnels can intensify excavation-induced unloading in the surrounding rock,increasing deformation demand and failure risk during construction.This study combines laboratory model tests with FLAC3D simulations to evaluate the stabilizing role of prestressed anchor cables and to establish an energy-balance framework for support optimization.Comparative model tests of existing and enlarged tunnel sections,with and without anchors,show that reinforcement increases load-carrying capacity,reduces displacement,and confines damage to more localized zones.The numerical simulations reproduce displacement fields,shear-strain localization,and plastic-zone evolution with good agreement against the experimental observations.The energy framework is implemented in the in-situ simulations by quantifying unloading-related energy release in the rock mass and reinforcement work contributed by the anchors,and by introducing an energy release–reinforcement ratio as a stability indicator.Parametric analyses indicate that anchor length,spacing,and prestress influence stability in a nonlinear manner,with diminishing returns once reinforcement extends beyond the mechanically dominant deformation zone.An efficient parameter window is identified that improves deformation and yielding control while avoiding unnecessary reinforcement.The results provide an energy-consistent and design-oriented basis for prestressed anchorage selection in large-span tunnel expansion.展开更多
Intervention strategies to control non-point source nitrogen(N)and phosphorus(P)pollution in agriculture are expensive and there is a trade-off between engineering cost and treatment effectiveness.Implementing strateg...Intervention strategies to control non-point source nitrogen(N)and phosphorus(P)pollution in agriculture are expensive and there is a trade-off between engineering cost and treatment effectiveness.Implementing strategies often result in unsatisfactory outcomes and massive engineering costs when managing diffusive pollution in agricultural catchments.To address this issue,this paper proposes a robust,handy,catchment N&P decision support system(CNPDSS),an Android-based smartphone system integrated with a web-based geographic information system(GIS).The CNPDSS aims to provide artificial intelligence-driven decisions that minimize N&P loadings and engineering costs for mitigating pollution in agricultural catchments.It consists of four components:a general user interface(GUI),GIS,N&P pollution modeling(NPPM),and a DSS.The CNPDSS simplifies the GUI and integrates GIS modules to create a user-friendly interface,enabling non-professional users to operate the system easily through intuitive actions.The NPPM uses straightforward empirical models to predict N&P loadings,enhancing efficiency by avoiding excessive parameters.Taking into account the N&P movement pathway in the catchment,the DSS incorporates three control measures:source reduction in farmland(before migration stage),process retention by ecological ditch(midway transport stage),and down-end purification by constructed wetland(waterbody discharge stage),to formulate a comprehensive ternary controlling strategy.To optimize the cost-effectiveness of any proposed N&P control strategies for sub-catchments,a differential evolution algorithm(DEA)is employed in CNPDSS to carry out a dual-objective decision-making optimization computation.In this study,the CNPDSS is applied to a case study in an agricultural catchment in Central China to develop the most cost-effective ternary N&P control strategies that ensure the catchment water quality within Criterion Ⅲ of the Chinese Surface Water Quality Standard GB3838-2002 is met(total N concentration≤1.0 mg L^(-1)and total P concentration≤0.2 mg L^(-1)).Our results demonstrate that the CNPDSS is feasible and also possesses an adaptive design and flexible architecture to enable its generalization and extension to support strong hands-on applications in other catchments.展开更多
Andrew Wangota,a 48-year-old Ugandan farmer,has been using agrivoltaics technology,a solar technology that uses agricultural land for both food production and solar power generation,on his farm in Bunashimolo Parish,B...Andrew Wangota,a 48-year-old Ugandan farmer,has been using agrivoltaics technology,a solar technology that uses agricultural land for both food production and solar power generation,on his farm in Bunashimolo Parish,Bukyiende Subcounty in Uganda where he has been cultivating plantain,coffee and Irish potatoes for the past 16 years.展开更多
Parkinson’s disease(PD)is a debilitating neurological disorder affecting over 10 million people worldwide.PD classification models using voice signals as input are common in the literature.It is believed that using d...Parkinson’s disease(PD)is a debilitating neurological disorder affecting over 10 million people worldwide.PD classification models using voice signals as input are common in the literature.It is believed that using deep learning algorithms further enhances performance;nevertheless,it is challenging due to the nature of small-scale and imbalanced PD datasets.This paper proposed a convolutional neural network-based deep support vector machine(CNN-DSVM)to automate the feature extraction process using CNN and extend the conventional SVM to a DSVM for better classification performance in small-scale PD datasets.A customized kernel function reduces the impact of biased classification towards the majority class(healthy candidates in our consideration).An improved generative adversarial network(IGAN)was designed to generate additional training data to enhance the model’s performance.For performance evaluation,the proposed algorithm achieves a sensitivity of 97.6%and a specificity of 97.3%.The performance comparison is evaluated from five perspectives,including comparisons with different data generation algorithms,feature extraction techniques,kernel functions,and existing works.Results reveal the effectiveness of the IGAN algorithm,which improves the sensitivity and specificity by 4.05%–4.72%and 4.96%–5.86%,respectively;and the effectiveness of the CNN-DSVM algorithm,which improves the sensitivity by 1.24%–57.4%and specificity by 1.04%–163%and reduces biased detection towards the majority class.The ablation experiments confirm the effectiveness of individual components.Two future research directions have also been suggested.展开更多
The roadway support in many places of Jiulongkou Colliery, Fengfeng Mining Bureau, such as in the Permanent transportation roadway, was failed or locally caved, which seriously affected the colliery’s coal production...The roadway support in many places of Jiulongkou Colliery, Fengfeng Mining Bureau, such as in the Permanent transportation roadway, was failed or locally caved, which seriously affected the colliery’s coal production performance and safety. Based on analysis of supporting objects for roadway repairing, this paper proposes the supporting parameters and condruction technics. The industrial ted of 70m long roadway repairing shows that the proposed parameters and technics of bolt shotcrete and mesh support for roadway repairing are reasouable, bring good technical and economic results for the colliery, and the repairing is successful.展开更多
This paper presents a semi-active strategy for seismic protection of a benchmark cable-stayed bridge with consideration of multiple-support excitations. In this control strategy, Magnetorheological (MR) dampers are pr...This paper presents a semi-active strategy for seismic protection of a benchmark cable-stayed bridge with consideration of multiple-support excitations. In this control strategy, Magnetorheological (MR) dampers are proposed as control devices, a LQG-clipped-optimal control algorithm is employed. An active control strategy, shown in previous researches to perform well at controlling the benchmark bridge when uniform earthquake motion was assumed, is also used in this study to control this benchmark bridge with consideration of multiple-support excitations. The performance of active control system is compared to that of the presented semi-active control strategy. Because the MR fluid damper is a con-trollable energy- dissipation device that cannot add mechanical energy to the structural system, the proposed control strategy is fail-safe in that bounded-input, bounded-output stability of the controlled structure is guaranteed. The numerical results demonstrated that the performance of the presented control design is nearly the same as that of the active control system; and that the MR dampers can effectively be used to control seismically excited cable-stayed bridges with multiple-support excitations.展开更多
A device for supporting soft rock masses combined with a constant resistance structure characterized by constant resistance and large deformation at the end of a steel bar, known as the constant resistance and large d...A device for supporting soft rock masses combined with a constant resistance structure characterized by constant resistance and large deformation at the end of a steel bar, known as the constant resistance and large deformation（CRLD） bolt, has recently been developed to counteract soft rock swelling that often occurs during deep mining. In order to further study the mechanical properties of the CRLD bolt, we investigated its mechanical properties by comparison with the conventional strength bolt（rebar） using static pull tests on many aspects, including supporting capacity, elongation, radial deformation, and energy absorption. The tests verified that the mechanical defects of the rebar, which include the decrease of bolt diameter, reduction of supporting capacity, and emergence and evolution of fracture until failure during the whole pull process, were caused by the Poisson＇s ratio effect. Due to the special structure set on the CRLD bolt, the bolt presents a seemingly unusual phenomenon of the negative Poisson＇s ratio effect, i.e., the diameter of the constant resistance structure increases while under-pulling. It is the very effect that ensures the extraordinary mechanical properties, including high resistance, large elongation, and strong energy absorption. According to the comparison and analysis of numerical simulation and field test, we can conclude that the CRLD bolt works better than the rebar bolt.展开更多
Thin-walled parts are widely used in the aerospace industry owing to their light weight and high specific strength.However,due to the low rigidity of thin-walled parts,elastic deformation and chatter easily occur,whic...Thin-walled parts are widely used in the aerospace industry owing to their light weight and high specific strength.However,due to the low rigidity of thin-walled parts,elastic deformation and chatter easily occur,which seriously affect the machining accuracy and workpiece surface quality.To solve this problem,several supporting technologies have been reported in recent years.This paper reviews the recent research progress of flexible supporting technologies in the aerospace field by classifying them based on different principles and characteristics.The principle,progress,advantages,and limitations of the technologies are expounded by systematic comparison and summarized.Finally,the challenges and future development trends of flexible supporting technology,which will provide guidelines for further research,are discussed.展开更多
基金support for carrying out this work was provided by the Doctoral Research Foundation of Weifang University(2024BS20)Science and Technology Development Plan Foundation of Weifang(2024GX017).
文摘Photocatalytic nitrogen fixation (PNF) is a promising alternative to the Haber-Bosch process.It achieves green ammonia production by utilizing solar energy for nitrogen fixation under mild conditions.While nanoscale photocatalysts offer enhanced performance due to their high surface area and abundant active sites,their small size makes them difficult to recover and prone to agglomeration.These bottlenecks severely limit industrial application.A promising solution is to immobilize the catalysts onto support surfaces.This paper provides a systematic review of recent advances in the design of immobilized photocatalysts for ammonia synthesis.It begins by outlining the key benefits of immobilization strategies,particularly in improving catalyst stability,recyclability,and overall photocatalytic performance.The working mechanisms and features of various immobilization techniques are then categorized and explained,covering physical adsorption/deposition,chemical bonding,in situ growth,and hybrid physico-chemical methods.Supported materials and common substrate types are also summarized.Furthermore,the widely used configurations of photoreactors suitable for immobilized systems are introduced.Finally,the review identifies current research limitations and challenges,and offers perspectives on future developments in the field of immobilized photocatalysis.
基金Project supported by the National Natural Science Foundation of China(Nos.52405095,12272089,and 92360305)the Guangdong Basic and Applied Basic Research Foundation of China(No.2023A1515110557)+4 种基金the Natural Science Foundation of Liaoning Province of China(No.2023-BSBA-102)the Open Fund of National Key Laboratory of Particle Transport and Separation Technology of China(No.WZKF-2024-6)the Open Project of Guangxi Key Laboratory of Automobile Components and Vehicle Technology of China(Nos.2024GKLACVTKF07 and 2024GKLACVTKF06)the Basic Research Projects of Liaoning Provincial Department of Education of China(No.JYTQN2023162)the Fundamental Research Funds for the Central Universities of China(No.N2403022)。
文摘The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometric distortions, leading to a diminution in the predictive accuracy of the distorted similitude. To address this challenge, this study formulates a novel set of scaling laws, tailored to account for the intricate geometric distortions associated with elastic rings. The proposed scaling laws are formulated based on the intrinsic deformation characteristics of elastic rings, rather than the traditional systemic governing equations. Numerical and experimental cases are conducted to assess the efficacy and precision of the proposed scaling laws, and the obtained results are compared with those achieved by traditional methods. The outcomes demonstrate that the scaling laws put forth by this study significantly enhance the predictive capabilities for deformations of elastic rings.
基金Project(2023AH051167)supported by the Natural Science Research Project of Anhui Educational Committee,ChinaProject(AHBP2024B-04)supported by the Foundation of Anhui Engineering Research Center of New Explosive Materials and Blasting Technology,China+1 种基金Project(GXZDSYS2023103)supported by the Open Fund for Anhui Key Laboratory of Mining Construction Engineering,ChinaProjects(52274071,52404155)supported by the National Natural Science Foundation of China。
文摘Aiming at the problem of dynamic instability of hard-brittle jointed rock surrounding in deep tunnel/roadway engineering,combining with the support concepts of"coupling rigidity with flexibility"and"overcoming rigidity by flexibility",the prevention and control method with"rigid-flexible coupling(R-F-C)"was put forward.Through numerical simulation calculation,the impact damage process,acoustic emission(AE)evolution characteristics,and element stress/displacement evolution characteristics of unsupported surrounding rock structure model,rigid supporting surrounding rock structure model,and"R-F-C"supporting surrounding rock structure model under horizontal bidirectional impact loading were compared and analyzed.Based on the theory of stress wave propagation,the dynamic instability catastrophe mechanism of three kinds of supporting structure models induced by horizontal bidirectional impact loading was revealed.Based on the Mohr-Coulomb strength theory,the stress discrimination methods of dynamic catastrophe of surrounding rock induced by horizontal bidirectional impact loading under three kinds of supporting structures were proposed.Combined with the above numerical simulation study,the explosion impact physical and mechanical test of"R-F-C"surrounding rock supporting plate structure was further designed and carried out.Finally,combined with the"conceptual model of ball-cliff potential energy instability",the energy driving theory and energy transformation mechanism of impact-induced rockburst under three kinds of supporting structures were discussed deeply.The research results provided a scientific basis for further promoting the effective application of"R-F-C"supporting structure in the prevention and control of dynamic instability of deep tunnel/roadway surrounding rock.
基金supported by the International Institute of Earthquake Engineering and Seismology(IIEES) as technical project No.760
文摘The primary goal of this study is to provide an efficient numerical tool to analyze the seismic performance of nailed walls.Modeling such excavation supports involves complexities due partly to the interaction of support with soil and partly because of the amplification of seismic waves through an excavation wall.Consequently,innovative modeling is suggested herein,incorporating the calibration of the soil constitutive model in a targeted range of stress and strain,and the detection of a natural period of complex systems,including soil and structure,while benefiting from Rayleigh damping to filter unwanted noises.The numerical model was achieved by simulating a previous centrifuge test of the excavation wall,manifested at the pre-failure state.Notably,the calibration of the soil constitutive model through empirical relations,which replaces the numerical reproduction of an element test,more accurately simulated the soil-nail-wall interaction.Two factors were crucial to a successful result.First,probing the natural period of the complicated geometry of the model by applying white noises.Second,considering Rayleigh damping to withdraw unwanted noises and thus assess their permanent effects on the model.Rayleigh damping was applied instead of filtering the obtained results.
文摘Autism spectrum disorder is a developmental disorder impacting a child’s social interactions,behaviors,and communication skills.One of the crucial aspects of autism care,which is often overlooked,is the parent’s mental health status while trying to improve and overcome challenges faced by their child.A study by Lu et al examined the effectiveness of remote family psychological support courses on the mental health status of parents having children with autism spectrum disorder.It was found that the integration of these remote psychological courses with conventional care had a positive impact on the parents by reducing their stress levels,leading to an increase in their competence,and hence they could engage effectively in child therapy.However,a long-term study is necessary to assess whether these interventions have a sustained effect.The study emphasizes the need for developing such culturally sensitive intervention models on a global scale,making them accessible to all and improving autism care support.
基金Projects(2023 YFC 2907602,2022 YFF 1303302)supported by the National Key Research and Development Project of ChinaProject(52342404)supported by the National Natural Science Foundation of China+2 种基金Project(GXXT-2021-075)supported by the University Synergy Innovation Program of Anhui Province,ChinaProject(2022AH010053)supported by Excellent Scientific Research and Innovation Team of Universities in Anhui Province,ChinaProject(2022xscx080)supported by Anhui Provincial Department of Education Graduate Student Academic Innovation Fund,China。
文摘To study the influence of support timing and support strength on the mechanical properties and deformation damage characteristics of a single-sided unloaded rock mass,a true triaxial perturbation unloaded rock testing system was used to conduct rock damage tests on sandstone with different support timing and strength paths.Based on the acoustic emission monitoring system,the spatial and temporal evolution characteristics of the whole process of rock body loaded instability under two stress paths were studied,and the mechanism of the reinforcing effect of stress support on the unloaded rock mass was analyzed.The results show that,within the scope of this study,both earlier applications of shoring and an increase in shoring strength can effectively improve the ultimate bearing capacity of the unloaded rock,which increases the ultimate bearing capacity of the unloaded rock mass by 60.31% and 54.96%,respectively;There is a phenomenon of rebound deformation of the rock mass during sudden changes in stress(single-sided unloading,stress support),which shows opposite expansion and compression platforms on the stress−strain curve;The crack evolution of unloaded rock under different stress support conditions shows the state law of"initial crack activation→middle steady state expansion→late main crack penetration",and the lagging support significantly accelerates the crack evolution from local activation to main penetration;The single-sided unloading and stress-supporting stages have less influence on the unloading deformationsσ_(1u),σ_(2u) and support deformationsσ_(1) t,σ_(2t) in theσ_(1) andσ_(2)directions,while they show significant response characteristics toσ_(3u),σ_(vu) and σ_(3) t,σ_(vt),and with the increase of the support strength,the stress-supporting stagesσ_(3) t,σ_(vt) gradually increase and exceed the deformations generated by the unloading stagesσ_(3u),σ_(vu);The increase of support strength can effectively compensate for the rock stress loss caused by unloading,which makes the maximum,minimum,and volumetric strain support coefficients during the loading and unloading of the rock body increase gradually while the effect on the intermediate principal strain support coefficient is small;During loading,the support strength of rock masses seeks a new bearing area by regulating stress equilibrium states.This process primarily manifests as a shift in the locations of the crushing zone and the main bearing area,accompanied by a corresponding transformation in failure patterns.Consequently,the rock mass transitions from asymmetric three-zone damage under no or weak support to approximate symmetric three-zone damage under strong support.Simultaneously,the main load-bearing area of the rock mass shifts from deep bearing in the unsupported to middle bearing under strong support as the support strength increases.
基金supported by the Gansu Provincial Natural Science Foundation(grant number 25JRRA074)the Gansu Provincial Key R&D Science and Technology Program(grant number 24YFGA060)the National Natural Science Foundation of China(grant number 62161019).
文摘Modern intelligent systems,such as autonomous vehicles and face recognition,must continuously adapt to new scenarios while preserving their ability to handle previously encountered situations.However,when neural networks learn new classes sequentially,they suffer from catastrophic forgetting—the tendency to lose knowledge of earlier classes.This challenge,which lies at the core of class-incremental learning,severely limits the deployment of continual learning systems in real-world applications with streaming data.Existing approaches,including rehearsalbased methods and knowledge distillation techniques,have attempted to address this issue but often struggle to effectively preserve decision boundaries and discriminative features under limited memory constraints.To overcome these limitations,we propose a support vector-guided framework for class-incremental learning.The framework integrates an enhanced feature extractor with a Support Vector Machine classifier,which generates boundary-critical support vectors to guide both replay and distillation.Building on this architecture,we design a joint feature retention strategy that combines boundary proximity with feature diversity,and a Support Vector Distillation Loss that enforces dual alignment in decision and semantic spaces.In addition,triple attention modules are incorporated into the feature extractor to enhance representation power.Extensive experiments on CIFAR-100 and Tiny-ImageNet demonstrate effective improvements.On CIFAR-100 and Tiny-ImageNet with 5 tasks,our method achieves 71.68%and 58.61%average accuracy,outperforming strong baselines by 3.34%and 2.05%.These advantages are consistently observed across different task splits,highlighting the robustness and generalization of the proposed approach.Beyond benchmark evaluations,the framework also shows potential in few-shot and resource-constrained applications such as edge computing and mobile robotics.
基金supported by the National Natural Science Foundation of China(12473085).
文摘The neutral surface of a concave thin mirror is too close to the mirror surface,which makes it difficult to effectively mount the flexible structure and increases the mirror surface shape error.To address this problem,we design a flexible support structure including connectors,a support plate,and flexible structures,and construct an equivalent mirror by installing connectors and a support plate on the back of the mirror.While ensuring that the neutral surface of the equivalent mirror is moved away from the mirror surface,we optimize the support structure so that the rotary center of the flexible structure is located on the neutral surface of the equivalent mirror,avoiding the tilting moment.Following design and modeling of the structure,we analyze the static and dynamic characteristics using a finite element simulation,finding a root-mean-square(RMS)value for the surface shape error of 9.28 nm under the coupled effects of 1g gravity load,4℃ temperature rise,and 0.005 mm unevenness assembly error,with a fundamental frequency of 170.75 Hz,which all meet the design requirements.Finally,we carry out a surface shape error test of the mirror assembly,confirming it to meet the design index requirement of the mirror assembly.Simulation and test results verify the reliability and effectiveness of our proposed support structure.
文摘Objective:To explore the clinical effect of personalized nutritional support in elderly women with gestational diabetes(GDM),and explore its impact on the incidence of maternal complications and pregnancy outcomes.Methods:A total of 90 elderly pregnant women with gestational diabetes who were delivered in our hospital from January 2023 to January 2024 were selected as the research objects.They were randomly divided into an observation group and a control group,with 45 cases in each group.The control group only received routine pregnancy care and basic nutrition guidance,while the observation group received personalized nutrition support on this basis.Compare the blood glucose control,incidence of pregnancy complications,pregnancy outcomes,and neonatal outcomes between two groups of parturient.Result:After intervention,the fasting blood glucose(FPG),2-hour postprandial blood glucose(2hPG),and glycated hemoglobin(HbA1c)of the observation group were significantly lower than those of the control group,and the differences were statistically significant(p<0.05);The incidence of complications such as gestational hypertension syndrome,polyhydramnios,premature rupture of membranes,and postpartum hemorrhage in the observation group was significantly lower than that in the control group,and the difference was statistically significant(p<0.05);The cesarean section rate in the observation group was significantly lower than that in the control group,and the incidence of adverse neonatal outcomes such as fetal distress,macrosomia,neonatal asphyxia,and neonatal hypoglycemia in the observation group was significantly lower than that in the control group,with statistical significance(p<0.05).Conclusion:Individualized nutritional support for elderly women with gestational diabetes can effectively improve the level of maternal blood sugar control,reduce the incidence of complications during pregnancy,and improve the outcome of pregnancy and neonatal outcomes,which is of high clinical value.
基金supported by the China Agriculture Research System of MOF and MARAthe National Natural Science Foundation of China (31872337 and 31501919)the Agricultural Science and Technology Innovation Project,China (ASTIP-IAS02)。
文摘The advantages of genome selection(GS) in animal and plant breeding are self-evident.Traditional parametric models have disadvantage in better fit the increasingly large sequencing data and capture complex effects accurately.Machine learning models have demonstrated remarkable potential in addressing these challenges.In this study,we introduced the concept of mixed kernel functions to explore the performance of support vector machine regression(SVR) in GS.Six single kernel functions(SVR_L,SVR_C,SVR_G,SVR_P,SVR_S,SVR_L) and four mixed kernel functions(SVR_GS,SVR_GP,SVR_LS,SVR_LP) were used to predict genome breeding values.The prediction accuracy,mean squared error(MSE) and mean absolute error(MAE) were used as evaluation indicators to compare with two traditional parametric models(GBLUP,BayesB) and two popular machine learning models(RF,KcRR).The results indicate that in most cases,the performance of the mixed kernel function model significantly outperforms that of GBLUP,BayesB and single kernel function.For instance,for T1 in the pig dataset,the predictive accuracy of SVR_GS is improved by 10% compared to GBLUP,and by approximately 4.4 and 18.6% compared to SVR_G and SVR_S respectively.For E1 in the wheat dataset,SVR_GS achieves 13.3% higher prediction accuracy than GBLUP.Among single kernel functions,the Laplacian and Gaussian kernel functions yield similar results,with the Gaussian kernel function performing better.The mixed kernel function notably reduces the MSE and MAE when compared to all single kernel functions.Furthermore,regarding runtime,SVR_GS and SVR_GP mixed kernel functions run approximately three times faster than GBLUP in the pig dataset,with only a slight increase in runtime compared to the single kernel function model.In summary,the mixed kernel function model of SVR demonstrates speed and accuracy competitiveness,and the model such as SVR_GS has important application potential for GS.
文摘This study investigated the effects of parental involvement,parenting stress,and social support on the social skills of school-aged children(6-18 years old)with intellectual disabilities(ID).Data were collected from 280 Chinese parents(mothers=70.0%,fathers=30.0%)of children with ID through purposive sampling and analyzed using partial least squares structural equation modeling(PLS-SEM).The results indicated that parental involvement not only directly enhanced children’s social skills but also indirectly improved them by alleviating parenting stress,which acted as a partial mediator.Contrary to the stress-buffering hypothesis,social support did not moderate the negative impact of parenting stress on social skills.Theoretically,this study contributes by validating ecological systems theory through a shift in focus from individual deficits to family systems,while also challenging the conventional view of stress-buffering theory.Accordingly,parent-support programs should integrate practical involvement training with systematic stress reduction and provide tailored assistance such as behavior-management training and respite care.
基金funded by the National Key R&D Program of China,China(No.2024YFF0507903)the National Key Research and Development Program of China(Grant No.2024YFF0507904)the National Natural Science Foundation of China,China(Grant No.52379114).These supports are gratefully acknowledged.
文摘In-situ enlargement of super-large-span tunnels can intensify excavation-induced unloading in the surrounding rock,increasing deformation demand and failure risk during construction.This study combines laboratory model tests with FLAC3D simulations to evaluate the stabilizing role of prestressed anchor cables and to establish an energy-balance framework for support optimization.Comparative model tests of existing and enlarged tunnel sections,with and without anchors,show that reinforcement increases load-carrying capacity,reduces displacement,and confines damage to more localized zones.The numerical simulations reproduce displacement fields,shear-strain localization,and plastic-zone evolution with good agreement against the experimental observations.The energy framework is implemented in the in-situ simulations by quantifying unloading-related energy release in the rock mass and reinforcement work contributed by the anchors,and by introducing an energy release–reinforcement ratio as a stability indicator.Parametric analyses indicate that anchor length,spacing,and prestress influence stability in a nonlinear manner,with diminishing returns once reinforcement extends beyond the mechanically dominant deformation zone.An efficient parameter window is identified that improves deformation and yielding control while avoiding unnecessary reinforcement.The results provide an energy-consistent and design-oriented basis for prestressed anchorage selection in large-span tunnel expansion.
基金financially supported by the National Key Research and Development Program of China(2024YFD1700104 and 2022YFE0209200-03)the National Natural Science Foundation of China(42161144002 and 41977156)+3 种基金the Guangxi Natural Science Foundation,China(2022GXNSFBA035625)the Guangxi Technology Base and Talent Subject,China(Guike AD22035927)the Shandong Key Research and Development Project,China(2022TZXD0045)the State Key Laboratory of Earth System Numerical Modeling and Application,Institute of Atmospheric Physics,Chinese Academy of Sciences。
文摘Intervention strategies to control non-point source nitrogen(N)and phosphorus(P)pollution in agriculture are expensive and there is a trade-off between engineering cost and treatment effectiveness.Implementing strategies often result in unsatisfactory outcomes and massive engineering costs when managing diffusive pollution in agricultural catchments.To address this issue,this paper proposes a robust,handy,catchment N&P decision support system(CNPDSS),an Android-based smartphone system integrated with a web-based geographic information system(GIS).The CNPDSS aims to provide artificial intelligence-driven decisions that minimize N&P loadings and engineering costs for mitigating pollution in agricultural catchments.It consists of four components:a general user interface(GUI),GIS,N&P pollution modeling(NPPM),and a DSS.The CNPDSS simplifies the GUI and integrates GIS modules to create a user-friendly interface,enabling non-professional users to operate the system easily through intuitive actions.The NPPM uses straightforward empirical models to predict N&P loadings,enhancing efficiency by avoiding excessive parameters.Taking into account the N&P movement pathway in the catchment,the DSS incorporates three control measures:source reduction in farmland(before migration stage),process retention by ecological ditch(midway transport stage),and down-end purification by constructed wetland(waterbody discharge stage),to formulate a comprehensive ternary controlling strategy.To optimize the cost-effectiveness of any proposed N&P control strategies for sub-catchments,a differential evolution algorithm(DEA)is employed in CNPDSS to carry out a dual-objective decision-making optimization computation.In this study,the CNPDSS is applied to a case study in an agricultural catchment in Central China to develop the most cost-effective ternary N&P control strategies that ensure the catchment water quality within Criterion Ⅲ of the Chinese Surface Water Quality Standard GB3838-2002 is met(total N concentration≤1.0 mg L^(-1)and total P concentration≤0.2 mg L^(-1)).Our results demonstrate that the CNPDSS is feasible and also possesses an adaptive design and flexible architecture to enable its generalization and extension to support strong hands-on applications in other catchments.
文摘Andrew Wangota,a 48-year-old Ugandan farmer,has been using agrivoltaics technology,a solar technology that uses agricultural land for both food production and solar power generation,on his farm in Bunashimolo Parish,Bukyiende Subcounty in Uganda where he has been cultivating plantain,coffee and Irish potatoes for the past 16 years.
基金The work described in this paper was fully supported by a grant from Hong Kong Metropolitan University(RIF/2021/05).
文摘Parkinson’s disease(PD)is a debilitating neurological disorder affecting over 10 million people worldwide.PD classification models using voice signals as input are common in the literature.It is believed that using deep learning algorithms further enhances performance;nevertheless,it is challenging due to the nature of small-scale and imbalanced PD datasets.This paper proposed a convolutional neural network-based deep support vector machine(CNN-DSVM)to automate the feature extraction process using CNN and extend the conventional SVM to a DSVM for better classification performance in small-scale PD datasets.A customized kernel function reduces the impact of biased classification towards the majority class(healthy candidates in our consideration).An improved generative adversarial network(IGAN)was designed to generate additional training data to enhance the model’s performance.For performance evaluation,the proposed algorithm achieves a sensitivity of 97.6%and a specificity of 97.3%.The performance comparison is evaluated from five perspectives,including comparisons with different data generation algorithms,feature extraction techniques,kernel functions,and existing works.Results reveal the effectiveness of the IGAN algorithm,which improves the sensitivity and specificity by 4.05%–4.72%and 4.96%–5.86%,respectively;and the effectiveness of the CNN-DSVM algorithm,which improves the sensitivity by 1.24%–57.4%and specificity by 1.04%–163%and reduces biased detection towards the majority class.The ablation experiments confirm the effectiveness of individual components.Two future research directions have also been suggested.
文摘The roadway support in many places of Jiulongkou Colliery, Fengfeng Mining Bureau, such as in the Permanent transportation roadway, was failed or locally caved, which seriously affected the colliery’s coal production performance and safety. Based on analysis of supporting objects for roadway repairing, this paper proposes the supporting parameters and condruction technics. The industrial ted of 70m long roadway repairing shows that the proposed parameters and technics of bolt shotcrete and mesh support for roadway repairing are reasouable, bring good technical and economic results for the colliery, and the repairing is successful.
文摘This paper presents a semi-active strategy for seismic protection of a benchmark cable-stayed bridge with consideration of multiple-support excitations. In this control strategy, Magnetorheological (MR) dampers are proposed as control devices, a LQG-clipped-optimal control algorithm is employed. An active control strategy, shown in previous researches to perform well at controlling the benchmark bridge when uniform earthquake motion was assumed, is also used in this study to control this benchmark bridge with consideration of multiple-support excitations. The performance of active control system is compared to that of the presented semi-active control strategy. Because the MR fluid damper is a con-trollable energy- dissipation device that cannot add mechanical energy to the structural system, the proposed control strategy is fail-safe in that bounded-input, bounded-output stability of the controlled structure is guaranteed. The numerical results demonstrated that the performance of the presented control design is nearly the same as that of the active control system; and that the MR dampers can effectively be used to control seismically excited cable-stayed bridges with multiple-support excitations.
基金supported by National Key Research and Development Program(2016YFC0600901)the National Natural Science Foundation of China(Grant Nos.51374214,51134005 and 51574248)+1 种基金the Special Fund of Basic Research and Operating of China University of Mining&Technology,Beijing(Grant Nos.2009QL03)the State Scholarship Fund of China
文摘A device for supporting soft rock masses combined with a constant resistance structure characterized by constant resistance and large deformation at the end of a steel bar, known as the constant resistance and large deformation（CRLD） bolt, has recently been developed to counteract soft rock swelling that often occurs during deep mining. In order to further study the mechanical properties of the CRLD bolt, we investigated its mechanical properties by comparison with the conventional strength bolt（rebar） using static pull tests on many aspects, including supporting capacity, elongation, radial deformation, and energy absorption. The tests verified that the mechanical defects of the rebar, which include the decrease of bolt diameter, reduction of supporting capacity, and emergence and evolution of fracture until failure during the whole pull process, were caused by the Poisson＇s ratio effect. Due to the special structure set on the CRLD bolt, the bolt presents a seemingly unusual phenomenon of the negative Poisson＇s ratio effect, i.e., the diameter of the constant resistance structure increases while under-pulling. It is the very effect that ensures the extraordinary mechanical properties, including high resistance, large elongation, and strong energy absorption. According to the comparison and analysis of numerical simulation and field test, we can conclude that the CRLD bolt works better than the rebar bolt.
基金supported by National Natural Science Foundation of China(No.51975096,No.51905075)China Postdoctoral Science Foundation(No.2019M661090)Liao Ning Revitalization Talents Program(No.XLYC1807230)。
文摘Thin-walled parts are widely used in the aerospace industry owing to their light weight and high specific strength.However,due to the low rigidity of thin-walled parts,elastic deformation and chatter easily occur,which seriously affect the machining accuracy and workpiece surface quality.To solve this problem,several supporting technologies have been reported in recent years.This paper reviews the recent research progress of flexible supporting technologies in the aerospace field by classifying them based on different principles and characteristics.The principle,progress,advantages,and limitations of the technologies are expounded by systematic comparison and summarized.Finally,the challenges and future development trends of flexible supporting technology,which will provide guidelines for further research,are discussed.
