[Objective] The aim was to research prevention effects of 25％ azoxys trobin suspending agent to cucumber downy mildew.[Method] The test,including control group and four treatment groups with 450,600,and 750 g/hm2 25...[Objective] The aim was to research prevention effects of 25％ azoxys trobin suspending agent to cucumber downy mildew.[Method] The test,including control group and four treatment groups with 450,600,and 750 g/hm2 25％ azoxystrobin suspending agents,and 80％ mancozeb wettable powder,was carried out in 2012 and 2013 consecutively to test the prevention effects of 25％ azoxystrobin suspending agent to cucumber downy mildew.[Result] The prevention effects were significant of 25％ azoxystrobin suspending agent to cucumber downy mildew in the range of 70.0％-83.6％,and it is recommended 25％ azoxystrobin suspending agent at 600 g/hm2 be spread before plants diseased or in initial stage.In the whole stage,it was spread once every 7 d,totaling 3 times.[Conclusion] The research provides references for wide application of 25％ azoxystrobin suspending agent in production.展开更多
Performance test of a high precise accelerometer or an inertial sensor on the ground is inevitably limited by the seismic noise. A torsion pendulum has been used to investigate the performances of an electrostatic acc...Performance test of a high precise accelerometer or an inertial sensor on the ground is inevitably limited by the seismic noise. A torsion pendulum has been used to investigate the performances of an electrostatic accelerometer, where the test mass is suspended by a fiber to compensate for its weight, and this scheme demonstrates an advantage, compared with the high-voltage levitation scheme, in which the effect of the seismic noise can be suppressed for a few orders of magnitude in low frequencies. In this work, the capacitive electrode cage is proposed to be suspended by another pendulum, and theoretical analysis shows that the effects of the seismic noise can be further suppressed for more than one order by suspending the electrode cage.展开更多
To overcome the shortcomings of pouring sands, a thickener with the ability to suspend sands was developed. It is mixed with sands to form densified slurry, and can insure the sands against deposition, jamming pipelin...To overcome the shortcomings of pouring sands, a thickener with the ability to suspend sands was developed. It is mixed with sands to form densified slurry, and can insure the sands against deposition, jamming pipelines and de- hydration. The chemical structure of the thickener is introduced in this paper and the production process is studied. The main processes include immersion, decomposition, dilution and addition of additives. In order to produce a thickener with high viscosity to suspend sands, key factors must be controlled in each process: the immersion time is 2 h; the mass fraction of formaldehyde is 0.01% and mass of NaCO3 accounts for 15% of dry material; the water temperature is 65 ℃ in summer and 72 ℃ in winter and the decomposition time is 2 h in the reaction; the densified decomposition so- lution should be diluted to 1% mass fraction; the additives of calcium ions and pH indicators must be added to the di- luted liquid; the mass fraction of CaCl2 is 0.048% and the pH value of the solution is 7.5. The thickener is a gel with three-dimensional network structure, a liquid with non-Newtonian behaviour and the characteristics of pseudo-plastic material, a solution with little resistance and the ability to revive its oral primary viscosity. It has been successfully ap- plied in Shendong Mines and has great value and wide-spread prospective use.展开更多
Different from conventional switched reluctance motor(SRM),bearingless SRM not only provides torque but also supplies levitation force for free-friction of rotor.In order to make sure that bearingless SRM can steadily...Different from conventional switched reluctance motor(SRM),bearingless SRM not only provides torque but also supplies levitation force for free-friction of rotor.In order to make sure that bearingless SRM can steadily levitates in static and dynamic rotating operation,it is necessary to analyze suspending force.Therefore,suspending force performance of an improved bearingless SRM with permanent magnets in stator yoke is comprehensively investigated in this paper.Basic structure and operation principle with permanent magnets in stator yoke are introduced firstly.Furthermore,mathematical model is built up for design of suspending force.In addition,parametric analysis for levitation performance is implemented.Finally,validity of proposed method is verified by experimental results.展开更多
The southern part of the Ningxia Hui Autonomous Region in China was infamous for its poverty and serious soil erosion caused by over population. In order to alleviate poverty and backwardness, a plan was worked out: t...The southern part of the Ningxia Hui Autonomous Region in China was infamous for its poverty and serious soil erosion caused by over population. In order to alleviate poverty and backwardness, a plan was worked out: to remove 200,000 people to the north plain by developing newly irrigated land during the period of 1983-1992. The plan has been in operation for eight and half years to date. About 200,000 people have been removed from the poor southern part to the newly developed area, and 800,000 mu (1/ 15 ha) of desert land has been cultivated. Most of the migrants have been lifted out of poverty and the people’s life in the south is being improved. During the immigration process, a model, called 'Suspending Village', has been developed. In the article, the whole process of the development and the strategies are discussed.展开更多
Ningxia is located in the Northwest China. The Huanghe (Yellow River) flowsthrough from its middle--west to the north. It is a province in which the Chinese Muslim--Hui Nationality is concentrated, with about one thir...Ningxia is located in the Northwest China. The Huanghe (Yellow River) flowsthrough from its middle--west to the north. It is a province in which the Chinese Muslim--Hui Nationality is concentrated, with about one third of the total population, hence theNingxia Hui Autonomous Region. From 1983 to 1992, more than 200000 people展开更多
As a nonlinear,strong coupling and multi-variable system,the drive performance of bearingless switched reluctance motor(BLSRM)is always limited by its complicated electromagnetic properties.Generally,conventional PID ...As a nonlinear,strong coupling and multi-variable system,the drive performance of bearingless switched reluctance motor(BLSRM)is always limited by its complicated electromagnetic properties.Generally,conventional PID methods are used to achieve the basic control requirement in wide industrial applications,however its inherent operating principle limits its use on suspending control of BLSRM.In this paper,the suspending force system,which is separately controlled from torque system,is built based on an adaptive fuzzy PID controller to limit the rotor eccentric displacement with proper generation of radial force.When compared with a system adopted using conventional PID method for suspending force control,the proposed adaptive fuzzy PID method has superior performance in shortening the response time,reducing the maximum eccentric displacement error and higher speed range of operation due to its online self-turning of controller parameters.Both in simulation and experimental cases,comparison of results of the above two methods validates the effectiveness of the adaptive fuzzy PID controller for BLSRM drive system.展开更多
We report herein a rational approach for fabricating metal suspending nanostructures by nanoimprint lithography(NIL) and isotropic reactive ion etching(RIE).The approach comprises three principal steps:(1) mold fabric...We report herein a rational approach for fabricating metal suspending nanostructures by nanoimprint lithography(NIL) and isotropic reactive ion etching(RIE).The approach comprises three principal steps:(1) mold fabrication,(2) structure replication by NIL,and(3) suspending nanostructures creation by isotropic RIE.Using this approach,suspending nanostructures with Au,Au/Ti or Ti/Au bilayers,and Au/Ti/Au sandwiched structures are demonstrated.For Au nanostructures,straight suspending nanostructures can be obtained when the thickness of Au film is up to 50 nm for nano-bridge and 90 nm for nano-finger patterns.When the thickness of Au is below 50 nm for nano-bridge and 90 nm for nano-finger,the Au suspending nanostructures bend upward as a result of the mismatch of thermal expansion between the thin Au films and Si substrate.This leads to residual stresses in the thin Au films.For Au/Ti or Ti/Au bilayers nanostructures,the cantilevers bend toward Au film,since Au has a larger thermal expansion coefficient than that of Ti.While in the case of sandwich structures,straight suspending nanostructures are obtained,this may be due to the balance of residual stress between the thin films.展开更多
Molten salt reactors,being the only reactor type among Generation Ⅳ advanced nuclear reactors that utilize liquid fuels,offer inherent safety,high-temperature,and low-pressure operation,as well as the capability for ...Molten salt reactors,being the only reactor type among Generation Ⅳ advanced nuclear reactors that utilize liquid fuels,offer inherent safety,high-temperature,and low-pressure operation,as well as the capability for online fuel reprocessing.However,the fuel-salt flow results in the decay of delayed neutron precursors(DNPs)outside the core,causing fluctuations in the effective delayed neutron fraction and consequently impacting the reactor reactivity.Particularly in accident scenarios—such as a combined pump shutdown and the inability to rapidly scram the reactor—the sole reliance on negative temperature feedback may cause a significant increase in core temperature,posing a threat to reactor safety.To address these problems,this paper introduces an innovative design for a passive fluid-driven suspended control rod(SCR)to dynamically compensate for reactivity fluctuations caused by DNPs flowing with the fuel.The control rod operates passively by leveraging the combined effects of gravity,buoyancy,and fluid dynamic forces,thereby eliminating the need for an external drive mechanism and enabling direct integration within the active region of the core.Using a 150 MWt thorium-based molten salt reactor as the reference design,we develop a mathematical model to systematically analyze the effects of key parameters—including the geometric dimensions and density of the SCR—on its performance.We examine its motion characteristics under different core flow conditions and assess its feasibility for the dynamic compensation of reactivity changes caused by fuel flow.The results of this study demonstrate that the SCR can effectively counteract reactivity fluctuations induced by fuel flow within molten salt reactors.A sensitivity analysis reveals that the SCR’s average density exerts a profound impact on its start-up flow threshold,channel flow rate,resistance to fuel density fluctuations,and response characteristics.This underscores the critical need to optimize this parameter.Moreover,by judiciously selecting the SCR’s length,number of deployed units,and the placement we can achieve the necessary reactivity control while maintaining a favorable balance between neutron economy and heat transfer performance.Ultimately,this paper provides an innovative solution for the passive reactivity control in molten salt reactors,offering significant potential for practical engineering applications.展开更多
The reference paper 1 shows a primary approach to the assessment methods of disaster economic loss. In this paper, the prediction and assessment of indirect losses of disaster of production suspending and cutting in e...The reference paper 1 shows a primary approach to the assessment methods of disaster economic loss. In this paper, the prediction and assessment of indirect losses of disaster of production suspending and cutting in enterprises are studied and the prediction and assessment models are given. The methods can be applied not only to pre disaster prediction of losses caused by production suspending and cutting in enterprises, but also to after disaster losses assessment.展开更多
The transport of suspended particulate matter is a crucial aspect of studies on sediment source-to-sink processes.However,research on its transport patterns in high-erosion areas of low-latitude seas remains limited.T...The transport of suspended particulate matter is a crucial aspect of studies on sediment source-to-sink processes.However,research on its transport patterns in high-erosion areas of low-latitude seas remains limited.To elucidate modern land-sea interaction processes controlled by the monsoon climate,this study investigates the seasonal transport patterns and control mechanisms of suspended particulate matter in the western Sunda Shelf.Results reveal significant seasonal variations in the spatial distribution of suspended particulate matter concentrations,with elevated levels observed during autumn compared with spring.These differences are directly attributed to the East Asian monsoon,including seasonal monsoon precipitation and the associated transport dynamics.During the northeast monsoon,the Malay Peninsula serves as a primary source for the western sea area,with terrestrial materials from its rivers transported to the northern Gulf of Thailand.This transport pattern shifts to an S-shaped,clockwise circulation during upwelling events.Conversely,in the southwest monsoon,rivers in the northern Gulf of Thailand become the predominant sources for the Sunda Shelf,with terrestrial materials carried by clockwise currents toward the eastern Malay Peninsula.When upwelling occurs off the southern Indochina Peninsula,one branch heads toward the South China Sea and the other toward the southern tip of the Malay Peninsula.The seasonal variation in material sources is further supported by the distribution of clay minerals and the discrimination results of rare earth element proxies,including(La/Sm)UCC-(Gd/Yb)UCCand(La/Yb)UCC-(Gd/Yb)UCC,in surface sediments from the Sunda Shelf and surrounding marine areas.展开更多
The application of photocatalytic technology in algae killing is limited by the non-floatability and difficulty in recycling of the photocatalysts.Loading photocatalyst on magnetic or floatable carriers is the most po...The application of photocatalytic technology in algae killing is limited by the non-floatability and difficulty in recycling of the photocatalysts.Loading photocatalyst on magnetic or floatable carriers is the most popular method for overcoming the above inadequacies.In this work,a CdZnS/TiO_(2) membrane photocatalyst with adjustable suspended depth(include floating)and flexible assembly is designed,which is less prone to dislodgement due to in situ synthesis and has a wider range of applicability than previously reported photocatalysts.The photocatalytic removal of Microcystis aeruginosa revealed that the suspended depth and distribution format of the CdZnS/TiO_(2) membrane photocatalysts have striking effects on the photocatalytic removal performance of Microcystis aeruginosa,the photocatalytic removal efficiency of CdZnS/TiO_(2)-2 membrane photocatalysts for Microcystis aeruginosa could reach to 98.6%in 60 min when the photocatalysts assembled in the form of 3×3 arrays suspended at a depth of 2 cm from the liquid surface.A tiny amount of TiO_(2) loading allows the formation of Z-Scheme heterojunction,resulting in accelerating the separation efficiency of photogenerated carriers,preserving the photogenerated electrons and holes with stronger reduction and oxidation ability and inhabiting the photo-corrosion of CdZnS.展开更多
Accurate daily suspended sediment load(SSL)prediction is essential for sustainable water resource management,sediment control,and environmental planning.However,SSL prediction is highly complex due to its nonlinear an...Accurate daily suspended sediment load(SSL)prediction is essential for sustainable water resource management,sediment control,and environmental planning.However,SSL prediction is highly complex due to its nonlinear and dynamic nature,making traditional empirical models inadequate.This study proposes a novel hybrid approach,integrating the Adaptive Neuro-Fuzzy Inference System(ANFIS)with the Gradient-Based Optimizer(GBO),to enhance SSL forecasting accuracy.The research compares the performance of ANFIS-GBO with three alternative models:standard ANFIS,ANFIS with Particle Swarm Optimization(ANFIS-PSO),and ANFIS with Grey Wolf Optimization(ANFIS-GWO).Historical SSL and streamflow data from the Bailong River Basin,China,are used to train and validate the models.The input selection process is optimized using the Multivariate Adaptive Regression Splines(MARS)method.Model performance is evaluated using statistical metrics such as Root Mean Square Error(RMSE),Mean Absolute Error(MAE),Mean Absolute Percentage Error(MAPE),Nash Sutcliffe Efficiency(NSE),and Determination Coefficient(R^(2)).Additionally,visual assessments,including scatter plots,Taylor diagrams,and violin plots,provide further insights into model reliability.The results indicate that including historical SSL data improves predictive accuracy,with ANFIS-GBO outperforming the other models.ANFIS-GBO achieves the lowest RMSE and MAE and the highest NSE and R^(2),demonstrating its superior learning ability and adaptability.The findings highlight the effectiveness of nature-inspired optimization algorithms in enhancing sediment load forecasting and contribute to the advancement of AI-based hydrological modeling.Future research should explore the integration of additional environmental and climatic variables to enhance predictive capabilities further.展开更多
Urban transportation systems are facing severe challenges due to the rapid growth of the urban population,especially in China.Suspended monorail system(SMS),as a sky rail transportation form,can effectively alleviate ...Urban transportation systems are facing severe challenges due to the rapid growth of the urban population,especially in China.Suspended monorail system(SMS),as a sky rail transportation form,can effectively alleviate urban traffic congestion due to its independent right-of-way and minimal ground footprint.However,the SMS possesses a special traveling system with unique vehicle structure and bridge configuration,which results in significant differences in both the mechanisms and dynamics problems associated with train–bridge interaction(TBI)when contrasted with those of traditional railway systems.Therefore,a thorough understanding of the SMS dynamics is essential for ensuring the operational safety of the system.This article presents a state-of-the-art review of the TBI modeling methodologies,critical dynamic features,field tests,and practice of the SMS in China.Firstly,the development history,technical features,and potential dynamics problems of the SMS are briefly described,followed by the mechanical characteristics and mechanisms of the train–bridge interactive systems.Then,the modeling methodology of the fundamental elements in the suspended monorail TBI is systematically reviewed,including the suspended train subsystem,bridge subsystem,train–bridge interaction relationships,system excitations,and solution method.Further,the typical dynamic features of the TBI under various operational scenarios are elaborated,including different train speeds,a variety of line sections,and a natural wind environment.Finally,the first new energy-based SMS test line in the world is systematically introduced,including the composition and functionality of the system,the details of the conducted field tests,and the measured results of the typical dynamic responses.At the end of the paper,both the guidance on further improvement of the SMS and future research topics are proposed.展开更多
The flux of dissolved inorganic nitrogen(DIN),predominantly nitrate(NO_(3)^(-))and ammonium(NH_(4)^(+)),from land to coastal waters via rivers is commonly estimated simply by multiplying water flux with nitrogen conce...The flux of dissolved inorganic nitrogen(DIN),predominantly nitrate(NO_(3)^(-))and ammonium(NH_(4)^(+)),from land to coastal waters via rivers is commonly estimated simply by multiplying water flux with nitrogen concentration.Understanding DIN fluxes in gated estuaries is critical as these systems often serve as hotspots for nutrient transformations,influencing coastal water quality and ecosystem health.However,the subsequent interactions involving NO_(3)^(-)and NH_(4)^(+)adsorption or desorption on suspended sediments are often overlooked.To better understand the impact of these interactions on the overall NO_(3)^(-)and NH_(4)^(+)sorption or desorption and subsequently,the mobility and transport to the coastal zone,we conducted a series of NO_(3)^(-)and NH_(4)^(+)adsorption and desorption experiments.These experiments involved varying suspended sediment concentrations,particle sizes,salinities,and sea-salt ions to assess their potential effects.Results indicate that desorption of NO_(3)^(-)and NH_(4)^(+)from suspended sediments is more prominent than adsorption,with NH_(4)^(+)desorption being particularly significant.Notably,at low suspended particle concentrations and high salinity,NH_(4)^(+)desorption from sediments increased markedly,which further amplified in polyhaline conditions.This effect could result from ion pairing between NH_(4)^(+)and seawater anions,along with competition from seawater cations for sediment cation exchange sites,enhancing NH_(4)^(+)diffusion from estuarine sediments,and the elevated NH_(4)^(+)release could promote DIN transport to nearshore waters,especially in gated estuaries where sediment resuspension occurs.Given the critical role of NH_(4)^(+)in estuarine nitrogen cycling,ignoring these dynamics could lead to underestimations of DIN transport in river-estuary systems.Therefore,incorporating sediment dynamics into DIN flux estimations is crucial for accurately assessing nitrogen transport in gated estuaries.展开更多
This study investigates the nonlinear resonance responses of suspended cables subjected to multi-frequency excitations and time-delayed feedback.Two specific combinations and simultaneous resonances are selected for d...This study investigates the nonlinear resonance responses of suspended cables subjected to multi-frequency excitations and time-delayed feedback.Two specific combinations and simultaneous resonances are selected for detailed examination.Initially,utilizing Hamilton’s variational principle,a nonlinear vibration control model of suspended cables under multi-frequency excitations and longitudinal time-delayed velocity feedback is developed,and the Galerkin method is employed to obtain the discrete model.Subsequently,focusing solely on single-mode discretization,analytical solutions for the two simultaneous resonances are derived using the method of multiple scales.The frequency response equations are derived,and the stability analysis is presented for two simultaneous resonance cases.The results demonstrate that suspended cables exhibit complex nonlinearity under multi-frequency excitations.Multiple solutions under multi-frequency excitation can be distinguished through the frequency–response and the detuning-phase curves.By adjusting the control gain and time delay,the resonance range,response amplitude,and phase of suspended cables can be modified.展开更多
Aiming at the pain points of visually impaired people during travel,this research innovatively transforms an industrial quadruped robot into a guide dog device.By transplanting the PCS-9180 motion control system(1.7 m...Aiming at the pain points of visually impaired people during travel,this research innovatively transforms an industrial quadruped robot into a guide dog device.By transplanting the PCS-9180 motion control system(1.7 m/s,IP66),and integrating a multi-modal perception network with a lightweight YOLO11 model.Tests show that the pass-through rate in complex terrains is 98%,the response delay is 0.3 seconds,and the cost is 50%that of a guide dog.The research verifies the social value of the transformation of industrial robot technology.展开更多
Controllably tuning the sensing performance of flexible mechanical sensors is important for them to realize on-demand sensing of various mechanical stimuli in different application scenarios.However,current regulating...Controllably tuning the sensing performance of flexible mechanical sensors is important for them to realize on-demand sensing of various mechanical stimuli in different application scenarios.However,current regulating strategies focus on the construction process of individual sensors,the response performance of the as-formed sensors is still hard to autonomously tune with external stimulus changes like human skin.Here,we propose a new strategy that realizes post-tuning of the sensing performance by introducing a temperature-dependent phase transition elastomer into the sensing film.Through an interfacially confined photopolymerization reaction,a graphene-based phase-transition elastomeric(GPTE)film with a robust interface and excellent conductivity is well-formed at the water/air interface.Benefiting from the crystallization-melt dynamic switching in the elastomer network,the GPTE film could experience the reversible transformation between soft(1.65 MPa)and stiff(12.27MPa)states,showing huge changes of elastic modulus up to seven times near the phase transition temperature(28.5℃).Furthermore,the GPTE film is designed into a suspended perceptual configuration realizing the dynamic detection of 3D deformation adapted to temperature changes with up to 3.5-fold difference in response sensitivity.Finally,the self-adaptive sensing behavior of temperature-mediated 3D deformation is demonstrated by the effective detection of the dynamic stimulation process of cold and hot water droplets by the GPTE suspended film.The proposed strategy of phase transition-induced post-tuning of sensing performance could greatly facilitate flexible mechanical sensors towards a more intelligent one.展开更多
Mesoscale eddies are widespread in the global ocean,significantly influencing the physical,chemical,and biological structures of water column.Based on the CTD data and suspended particulate matter(SPM)data collected a...Mesoscale eddies are widespread in the global ocean,significantly influencing the physical,chemical,and biological structures of water column.Based on the CTD data and suspended particulate matter(SPM)data collected at 36 hydrographic stations during a field cruise in southern Mozambique Channel,combined with satellite altimeter observations,we identified a series of mesoscale eddies traversing the Mozambique Channel.Our hydrographic measurements,coupled with in situ chlorophyll fluorescence data,reveal that these eddies significantly influence thermohaline structure and chlorophyll distribution,which in turn affects primary productivity and SPM concentrations in the upper ocean.The cyclonic eddies facilitate the upwelling of cold subsurface water,leading to a shallowing of the pycnocline and the creation of a low-temperature anomaly with variable salinity anomalies at different depths.Conversely,anticyclonic eddies submerge warm surface water,deepening the pycnocline,and resulting in a high-temperature anomaly accompanied by distinct salinity patterns.Significantly,a coastal anticyclonic eddy was observed to intercept terrestrial material from the Delagoa Bight,redirecting it west of 36°E.This study presents unique and quasi-synchronous CTD datasets capturing mesoscale eddy impacts,and provided valuable insights into SPM variability within the often-neglected southern Mozambique Channel.展开更多
Ocean remote sensing satellites provide observations with high spatiotemporal resolution.However,the influence of clouds,fog,and haze frequently leads to significant data gaps.Accurate and effective estimation of thes...Ocean remote sensing satellites provide observations with high spatiotemporal resolution.However,the influence of clouds,fog,and haze frequently leads to significant data gaps.Accurate and effective estimation of these missing data is highly valuable for engineering and scientific research.In this study,the radial basis function(RBF)method is used to estimate the spatial distribution of total suspended matter(TSM)concentration in Hangzhou Bay using remote sensing data with severe data gaps.The estimation precision is validated by comparing the results with those of other commonly used interpolation methods,such as the Kriging method and the basic spline(B-spline)method.In addition,the applicability of the RBF method is explored.Results show that the estimation of the RBF method is significantly close to the observation in Hangzhou Bay.The average of the mean absolute error,mean relative error,and root mean square error in all the experiments is evidently smaller than those of the Kriging and B-spline interpolations,indicating that the proposed method is more appropriate for estimating the spatial distribution of the TSM in Hangzhou Bay.Finally,the TSM distribution in the blank observational area is predicted.This study can provide some reference values for handling watercolor remote sensing data.展开更多
文摘[Objective] The aim was to research prevention effects of 25％ azoxys trobin suspending agent to cucumber downy mildew.[Method] The test,including control group and four treatment groups with 450,600,and 750 g/hm2 25％ azoxystrobin suspending agents,and 80％ mancozeb wettable powder,was carried out in 2012 and 2013 consecutively to test the prevention effects of 25％ azoxystrobin suspending agent to cucumber downy mildew.[Result] The prevention effects were significant of 25％ azoxystrobin suspending agent to cucumber downy mildew in the range of 70.0％-83.6％,and it is recommended 25％ azoxystrobin suspending agent at 600 g/hm2 be spread before plants diseased or in initial stage.In the whole stage,it was spread once every 7 d,totaling 3 times.[Conclusion] The research provides references for wide application of 25％ azoxystrobin suspending agent in production.
基金Supported by the National Natural Science Foundation of China under Grant No 11235004
文摘Performance test of a high precise accelerometer or an inertial sensor on the ground is inevitably limited by the seismic noise. A torsion pendulum has been used to investigate the performances of an electrostatic accelerometer, where the test mass is suspended by a fiber to compensate for its weight, and this scheme demonstrates an advantage, compared with the high-voltage levitation scheme, in which the effect of the seismic noise can be suppressed for a few orders of magnitude in low frequencies. In this work, the capacitive electrode cage is proposed to be suspended by another pendulum, and theoretical analysis shows that the effects of the seismic noise can be further suppressed for more than one order by suspending the electrode cage.
基金Projects 50274068 Supported by National Natural Science Foundation of China and 20020290001 by Research Fund for Doctoral Program of HigherEducation
文摘To overcome the shortcomings of pouring sands, a thickener with the ability to suspend sands was developed. It is mixed with sands to form densified slurry, and can insure the sands against deposition, jamming pipelines and de- hydration. The chemical structure of the thickener is introduced in this paper and the production process is studied. The main processes include immersion, decomposition, dilution and addition of additives. In order to produce a thickener with high viscosity to suspend sands, key factors must be controlled in each process: the immersion time is 2 h; the mass fraction of formaldehyde is 0.01% and mass of NaCO3 accounts for 15% of dry material; the water temperature is 65 ℃ in summer and 72 ℃ in winter and the decomposition time is 2 h in the reaction; the densified decomposition so- lution should be diluted to 1% mass fraction; the additives of calcium ions and pH indicators must be added to the di- luted liquid; the mass fraction of CaCl2 is 0.048% and the pH value of the solution is 7.5. The thickener is a gel with three-dimensional network structure, a liquid with non-Newtonian behaviour and the characteristics of pseudo-plastic material, a solution with little resistance and the ability to revive its oral primary viscosity. It has been successfully ap- plied in Shendong Mines and has great value and wide-spread prospective use.
基金This work was supported by the National Natural Science Foundation of China under Grant 51777004.
文摘Different from conventional switched reluctance motor(SRM),bearingless SRM not only provides torque but also supplies levitation force for free-friction of rotor.In order to make sure that bearingless SRM can steadily levitates in static and dynamic rotating operation,it is necessary to analyze suspending force.Therefore,suspending force performance of an improved bearingless SRM with permanent magnets in stator yoke is comprehensively investigated in this paper.Basic structure and operation principle with permanent magnets in stator yoke are introduced firstly.Furthermore,mathematical model is built up for design of suspending force.In addition,parametric analysis for levitation performance is implemented.Finally,validity of proposed method is verified by experimental results.
文摘The southern part of the Ningxia Hui Autonomous Region in China was infamous for its poverty and serious soil erosion caused by over population. In order to alleviate poverty and backwardness, a plan was worked out: to remove 200,000 people to the north plain by developing newly irrigated land during the period of 1983-1992. The plan has been in operation for eight and half years to date. About 200,000 people have been removed from the poor southern part to the newly developed area, and 800,000 mu (1/ 15 ha) of desert land has been cultivated. Most of the migrants have been lifted out of poverty and the people’s life in the south is being improved. During the immigration process, a model, called 'Suspending Village', has been developed. In the article, the whole process of the development and the strategies are discussed.
文摘Ningxia is located in the Northwest China. The Huanghe (Yellow River) flowsthrough from its middle--west to the north. It is a province in which the Chinese Muslim--Hui Nationality is concentrated, with about one third of the total population, hence theNingxia Hui Autonomous Region. From 1983 to 1992, more than 200000 people
文摘As a nonlinear,strong coupling and multi-variable system,the drive performance of bearingless switched reluctance motor(BLSRM)is always limited by its complicated electromagnetic properties.Generally,conventional PID methods are used to achieve the basic control requirement in wide industrial applications,however its inherent operating principle limits its use on suspending control of BLSRM.In this paper,the suspending force system,which is separately controlled from torque system,is built based on an adaptive fuzzy PID controller to limit the rotor eccentric displacement with proper generation of radial force.When compared with a system adopted using conventional PID method for suspending force control,the proposed adaptive fuzzy PID method has superior performance in shortening the response time,reducing the maximum eccentric displacement error and higher speed range of operation due to its online self-turning of controller parameters.Both in simulation and experimental cases,comparison of results of the above two methods validates the effectiveness of the adaptive fuzzy PID controller for BLSRM drive system.
基金Supported by the National Natural Science Foundation of China (Grant No. 20573002)the Major State Basic Research Development Program of China (973Pprogram) (Grant No. 2001CB6105)
文摘We report herein a rational approach for fabricating metal suspending nanostructures by nanoimprint lithography(NIL) and isotropic reactive ion etching(RIE).The approach comprises three principal steps:(1) mold fabrication,(2) structure replication by NIL,and(3) suspending nanostructures creation by isotropic RIE.Using this approach,suspending nanostructures with Au,Au/Ti or Ti/Au bilayers,and Au/Ti/Au sandwiched structures are demonstrated.For Au nanostructures,straight suspending nanostructures can be obtained when the thickness of Au film is up to 50 nm for nano-bridge and 90 nm for nano-finger patterns.When the thickness of Au is below 50 nm for nano-bridge and 90 nm for nano-finger,the Au suspending nanostructures bend upward as a result of the mismatch of thermal expansion between the thin Au films and Si substrate.This leads to residual stresses in the thin Au films.For Au/Ti or Ti/Au bilayers nanostructures,the cantilevers bend toward Au film,since Au has a larger thermal expansion coefficient than that of Ti.While in the case of sandwich structures,straight suspending nanostructures are obtained,this may be due to the balance of residual stress between the thin films.
基金supported by Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2020261)Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA02010000)the Young Potential Program of Shanghai Institute of Applied Physics,Chinese Academy of Sciences(No.SINAP-YXJH-202412).
文摘Molten salt reactors,being the only reactor type among Generation Ⅳ advanced nuclear reactors that utilize liquid fuels,offer inherent safety,high-temperature,and low-pressure operation,as well as the capability for online fuel reprocessing.However,the fuel-salt flow results in the decay of delayed neutron precursors(DNPs)outside the core,causing fluctuations in the effective delayed neutron fraction and consequently impacting the reactor reactivity.Particularly in accident scenarios—such as a combined pump shutdown and the inability to rapidly scram the reactor—the sole reliance on negative temperature feedback may cause a significant increase in core temperature,posing a threat to reactor safety.To address these problems,this paper introduces an innovative design for a passive fluid-driven suspended control rod(SCR)to dynamically compensate for reactivity fluctuations caused by DNPs flowing with the fuel.The control rod operates passively by leveraging the combined effects of gravity,buoyancy,and fluid dynamic forces,thereby eliminating the need for an external drive mechanism and enabling direct integration within the active region of the core.Using a 150 MWt thorium-based molten salt reactor as the reference design,we develop a mathematical model to systematically analyze the effects of key parameters—including the geometric dimensions and density of the SCR—on its performance.We examine its motion characteristics under different core flow conditions and assess its feasibility for the dynamic compensation of reactivity changes caused by fuel flow.The results of this study demonstrate that the SCR can effectively counteract reactivity fluctuations induced by fuel flow within molten salt reactors.A sensitivity analysis reveals that the SCR’s average density exerts a profound impact on its start-up flow threshold,channel flow rate,resistance to fuel density fluctuations,and response characteristics.This underscores the critical need to optimize this parameter.Moreover,by judiciously selecting the SCR’s length,number of deployed units,and the placement we can achieve the necessary reactivity control while maintaining a favorable balance between neutron economy and heat transfer performance.Ultimately,this paper provides an innovative solution for the passive reactivity control in molten salt reactors,offering significant potential for practical engineering applications.
文摘The reference paper 1 shows a primary approach to the assessment methods of disaster economic loss. In this paper, the prediction and assessment of indirect losses of disaster of production suspending and cutting in enterprises are studied and the prediction and assessment models are given. The methods can be applied not only to pre disaster prediction of losses caused by production suspending and cutting in enterprises, but also to after disaster losses assessment.
基金the Basic Scientific Fund for National Public Research Institutes of China(No.2023Q03)the National Natural Science Foundation of China(Nos.42476078,42306091)+2 种基金the National Programme on Global Change and Air-Sea Interaction(Nos.GASI-04-HYDZ-02,GASI-02-SCS-CJB01)the China-Malaysia Cooperation Project‘Effect on Variability of Seasonal Monsoon on Sedimentary Process in Peninsular Malaysia Waters’the China-Thailand Cooperation Project‘Research on Vulnerability of Coastal Zone’。
文摘The transport of suspended particulate matter is a crucial aspect of studies on sediment source-to-sink processes.However,research on its transport patterns in high-erosion areas of low-latitude seas remains limited.To elucidate modern land-sea interaction processes controlled by the monsoon climate,this study investigates the seasonal transport patterns and control mechanisms of suspended particulate matter in the western Sunda Shelf.Results reveal significant seasonal variations in the spatial distribution of suspended particulate matter concentrations,with elevated levels observed during autumn compared with spring.These differences are directly attributed to the East Asian monsoon,including seasonal monsoon precipitation and the associated transport dynamics.During the northeast monsoon,the Malay Peninsula serves as a primary source for the western sea area,with terrestrial materials from its rivers transported to the northern Gulf of Thailand.This transport pattern shifts to an S-shaped,clockwise circulation during upwelling events.Conversely,in the southwest monsoon,rivers in the northern Gulf of Thailand become the predominant sources for the Sunda Shelf,with terrestrial materials carried by clockwise currents toward the eastern Malay Peninsula.When upwelling occurs off the southern Indochina Peninsula,one branch heads toward the South China Sea and the other toward the southern tip of the Malay Peninsula.The seasonal variation in material sources is further supported by the distribution of clay minerals and the discrimination results of rare earth element proxies,including(La/Sm)UCC-(Gd/Yb)UCCand(La/Yb)UCC-(Gd/Yb)UCC,in surface sediments from the Sunda Shelf and surrounding marine areas.
基金financially supported by the Natural Science Foundation of ShanDong(Nos.ZR2023QD152 and ZR2021MD002).
文摘The application of photocatalytic technology in algae killing is limited by the non-floatability and difficulty in recycling of the photocatalysts.Loading photocatalyst on magnetic or floatable carriers is the most popular method for overcoming the above inadequacies.In this work,a CdZnS/TiO_(2) membrane photocatalyst with adjustable suspended depth(include floating)and flexible assembly is designed,which is less prone to dislodgement due to in situ synthesis and has a wider range of applicability than previously reported photocatalysts.The photocatalytic removal of Microcystis aeruginosa revealed that the suspended depth and distribution format of the CdZnS/TiO_(2) membrane photocatalysts have striking effects on the photocatalytic removal performance of Microcystis aeruginosa,the photocatalytic removal efficiency of CdZnS/TiO_(2)-2 membrane photocatalysts for Microcystis aeruginosa could reach to 98.6%in 60 min when the photocatalysts assembled in the form of 3×3 arrays suspended at a depth of 2 cm from the liquid surface.A tiny amount of TiO_(2) loading allows the formation of Z-Scheme heterojunction,resulting in accelerating the separation efficiency of photogenerated carriers,preserving the photogenerated electrons and holes with stronger reduction and oxidation ability and inhabiting the photo-corrosion of CdZnS.
基金supported by the National Natural Science Foundation of China(52350410465)the General Projects of Guangdong Natural Science Research Projects(2023A1515011520).
文摘Accurate daily suspended sediment load(SSL)prediction is essential for sustainable water resource management,sediment control,and environmental planning.However,SSL prediction is highly complex due to its nonlinear and dynamic nature,making traditional empirical models inadequate.This study proposes a novel hybrid approach,integrating the Adaptive Neuro-Fuzzy Inference System(ANFIS)with the Gradient-Based Optimizer(GBO),to enhance SSL forecasting accuracy.The research compares the performance of ANFIS-GBO with three alternative models:standard ANFIS,ANFIS with Particle Swarm Optimization(ANFIS-PSO),and ANFIS with Grey Wolf Optimization(ANFIS-GWO).Historical SSL and streamflow data from the Bailong River Basin,China,are used to train and validate the models.The input selection process is optimized using the Multivariate Adaptive Regression Splines(MARS)method.Model performance is evaluated using statistical metrics such as Root Mean Square Error(RMSE),Mean Absolute Error(MAE),Mean Absolute Percentage Error(MAPE),Nash Sutcliffe Efficiency(NSE),and Determination Coefficient(R^(2)).Additionally,visual assessments,including scatter plots,Taylor diagrams,and violin plots,provide further insights into model reliability.The results indicate that including historical SSL data improves predictive accuracy,with ANFIS-GBO outperforming the other models.ANFIS-GBO achieves the lowest RMSE and MAE and the highest NSE and R^(2),demonstrating its superior learning ability and adaptability.The findings highlight the effectiveness of nature-inspired optimization algorithms in enhancing sediment load forecasting and contribute to the advancement of AI-based hydrological modeling.Future research should explore the integration of additional environmental and climatic variables to enhance predictive capabilities further.
基金supported by the National Natural Science Foundation of China(Grant Nos.52202483,52108476,and 52388102)。
文摘Urban transportation systems are facing severe challenges due to the rapid growth of the urban population,especially in China.Suspended monorail system(SMS),as a sky rail transportation form,can effectively alleviate urban traffic congestion due to its independent right-of-way and minimal ground footprint.However,the SMS possesses a special traveling system with unique vehicle structure and bridge configuration,which results in significant differences in both the mechanisms and dynamics problems associated with train–bridge interaction(TBI)when contrasted with those of traditional railway systems.Therefore,a thorough understanding of the SMS dynamics is essential for ensuring the operational safety of the system.This article presents a state-of-the-art review of the TBI modeling methodologies,critical dynamic features,field tests,and practice of the SMS in China.Firstly,the development history,technical features,and potential dynamics problems of the SMS are briefly described,followed by the mechanical characteristics and mechanisms of the train–bridge interactive systems.Then,the modeling methodology of the fundamental elements in the suspended monorail TBI is systematically reviewed,including the suspended train subsystem,bridge subsystem,train–bridge interaction relationships,system excitations,and solution method.Further,the typical dynamic features of the TBI under various operational scenarios are elaborated,including different train speeds,a variety of line sections,and a natural wind environment.Finally,the first new energy-based SMS test line in the world is systematically introduced,including the composition and functionality of the system,the details of the conducted field tests,and the measured results of the typical dynamic responses.At the end of the paper,both the guidance on further improvement of the SMS and future research topics are proposed.
基金Supported by the Tianjin Key R&D Program(No.21YFSNSN00220)。
文摘The flux of dissolved inorganic nitrogen(DIN),predominantly nitrate(NO_(3)^(-))and ammonium(NH_(4)^(+)),from land to coastal waters via rivers is commonly estimated simply by multiplying water flux with nitrogen concentration.Understanding DIN fluxes in gated estuaries is critical as these systems often serve as hotspots for nutrient transformations,influencing coastal water quality and ecosystem health.However,the subsequent interactions involving NO_(3)^(-)and NH_(4)^(+)adsorption or desorption on suspended sediments are often overlooked.To better understand the impact of these interactions on the overall NO_(3)^(-)and NH_(4)^(+)sorption or desorption and subsequently,the mobility and transport to the coastal zone,we conducted a series of NO_(3)^(-)and NH_(4)^(+)adsorption and desorption experiments.These experiments involved varying suspended sediment concentrations,particle sizes,salinities,and sea-salt ions to assess their potential effects.Results indicate that desorption of NO_(3)^(-)and NH_(4)^(+)from suspended sediments is more prominent than adsorption,with NH_(4)^(+)desorption being particularly significant.Notably,at low suspended particle concentrations and high salinity,NH_(4)^(+)desorption from sediments increased markedly,which further amplified in polyhaline conditions.This effect could result from ion pairing between NH_(4)^(+)and seawater anions,along with competition from seawater cations for sediment cation exchange sites,enhancing NH_(4)^(+)diffusion from estuarine sediments,and the elevated NH_(4)^(+)release could promote DIN transport to nearshore waters,especially in gated estuaries where sediment resuspension occurs.Given the critical role of NH_(4)^(+)in estuarine nitrogen cycling,ignoring these dynamics could lead to underestimations of DIN transport in river-estuary systems.Therefore,incorporating sediment dynamics into DIN flux estimations is crucial for accurately assessing nitrogen transport in gated estuaries.
基金supported in part by the National Natural Science Foundation of China(Grant No.12432001)Natural Science Foundation of Hunan Province(Grant Nos.2023JJ60527,2023JJ30152,and 2023JJ30259)the Natural Science Foundation of Changsha(KQ2202133).
文摘This study investigates the nonlinear resonance responses of suspended cables subjected to multi-frequency excitations and time-delayed feedback.Two specific combinations and simultaneous resonances are selected for detailed examination.Initially,utilizing Hamilton’s variational principle,a nonlinear vibration control model of suspended cables under multi-frequency excitations and longitudinal time-delayed velocity feedback is developed,and the Galerkin method is employed to obtain the discrete model.Subsequently,focusing solely on single-mode discretization,analytical solutions for the two simultaneous resonances are derived using the method of multiple scales.The frequency response equations are derived,and the stability analysis is presented for two simultaneous resonance cases.The results demonstrate that suspended cables exhibit complex nonlinearity under multi-frequency excitations.Multiple solutions under multi-frequency excitation can be distinguished through the frequency–response and the detuning-phase curves.By adjusting the control gain and time delay,the resonance range,response amplitude,and phase of suspended cables can be modified.
文摘Aiming at the pain points of visually impaired people during travel,this research innovatively transforms an industrial quadruped robot into a guide dog device.By transplanting the PCS-9180 motion control system(1.7 m/s,IP66),and integrating a multi-modal perception network with a lightweight YOLO11 model.Tests show that the pass-through rate in complex terrains is 98%,the response delay is 0.3 seconds,and the cost is 50%that of a guide dog.The research verifies the social value of the transformation of industrial robot technology.
基金supported by the National Key Research and Development Program of China(No.2022YFC2805200)the National Natural Science Foundation of China(No.52373094)+4 种基金Zhejiang Provincial Natural Science Foundation(No.LR25E030004)Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2023313)Sino-German Mobility Program(No.M-0424),Ningbo Major Research and Development Plan Project(No.20241ZDYF020148)Ningbo International Cooperation(No.2023H019)Ningbo Science&Technology Bureau(No.2024QL003)。
文摘Controllably tuning the sensing performance of flexible mechanical sensors is important for them to realize on-demand sensing of various mechanical stimuli in different application scenarios.However,current regulating strategies focus on the construction process of individual sensors,the response performance of the as-formed sensors is still hard to autonomously tune with external stimulus changes like human skin.Here,we propose a new strategy that realizes post-tuning of the sensing performance by introducing a temperature-dependent phase transition elastomer into the sensing film.Through an interfacially confined photopolymerization reaction,a graphene-based phase-transition elastomeric(GPTE)film with a robust interface and excellent conductivity is well-formed at the water/air interface.Benefiting from the crystallization-melt dynamic switching in the elastomer network,the GPTE film could experience the reversible transformation between soft(1.65 MPa)and stiff(12.27MPa)states,showing huge changes of elastic modulus up to seven times near the phase transition temperature(28.5℃).Furthermore,the GPTE film is designed into a suspended perceptual configuration realizing the dynamic detection of 3D deformation adapted to temperature changes with up to 3.5-fold difference in response sensitivity.Finally,the self-adaptive sensing behavior of temperature-mediated 3D deformation is demonstrated by the effective detection of the dynamic stimulation process of cold and hot water droplets by the GPTE suspended film.The proposed strategy of phase transition-induced post-tuning of sensing performance could greatly facilitate flexible mechanical sensors towards a more intelligent one.
基金Supported by the Taishan Scholar Project of Shandong Province (Nos.TS20190913,tsqn202211054)the Fundamental Research Funds for the Central Universities (No.202241007)the Youth Innovation Team Program in Colleges and Universities of Shandong Province (No.2022KJ045)
文摘Mesoscale eddies are widespread in the global ocean,significantly influencing the physical,chemical,and biological structures of water column.Based on the CTD data and suspended particulate matter(SPM)data collected at 36 hydrographic stations during a field cruise in southern Mozambique Channel,combined with satellite altimeter observations,we identified a series of mesoscale eddies traversing the Mozambique Channel.Our hydrographic measurements,coupled with in situ chlorophyll fluorescence data,reveal that these eddies significantly influence thermohaline structure and chlorophyll distribution,which in turn affects primary productivity and SPM concentrations in the upper ocean.The cyclonic eddies facilitate the upwelling of cold subsurface water,leading to a shallowing of the pycnocline and the creation of a low-temperature anomaly with variable salinity anomalies at different depths.Conversely,anticyclonic eddies submerge warm surface water,deepening the pycnocline,and resulting in a high-temperature anomaly accompanied by distinct salinity patterns.Significantly,a coastal anticyclonic eddy was observed to intercept terrestrial material from the Delagoa Bight,redirecting it west of 36°E.This study presents unique and quasi-synchronous CTD datasets capturing mesoscale eddy impacts,and provided valuable insights into SPM variability within the often-neglected southern Mozambique Channel.
基金supported by the Open Funds for Hubei Key Laboratory of Marine Geological Resources,China University of Geosciences(No.MGR202308)the Natural Science Foundation of Shandong Province(No.ZR2020MD085)+3 种基金the National Natural Science Foundation of China(No.41821004)the Taishan Scholar Program(No.tstp2022114)the Shandong Provincial Natural Science Foundation(No.DKXZZ202206)the National Key Research and Development Program of China(No.2016YFC1402404).
文摘Ocean remote sensing satellites provide observations with high spatiotemporal resolution.However,the influence of clouds,fog,and haze frequently leads to significant data gaps.Accurate and effective estimation of these missing data is highly valuable for engineering and scientific research.In this study,the radial basis function(RBF)method is used to estimate the spatial distribution of total suspended matter(TSM)concentration in Hangzhou Bay using remote sensing data with severe data gaps.The estimation precision is validated by comparing the results with those of other commonly used interpolation methods,such as the Kriging method and the basic spline(B-spline)method.In addition,the applicability of the RBF method is explored.Results show that the estimation of the RBF method is significantly close to the observation in Hangzhou Bay.The average of the mean absolute error,mean relative error,and root mean square error in all the experiments is evidently smaller than those of the Kriging and B-spline interpolations,indicating that the proposed method is more appropriate for estimating the spatial distribution of the TSM in Hangzhou Bay.Finally,the TSM distribution in the blank observational area is predicted.This study can provide some reference values for handling watercolor remote sensing data.
