最新刊期
卷 48 ， 期 5 ， 2016
- 摘要：Abstract:Aiming at the stability problems of the surrounding rock mass in the underground caverns at the Houziyan hydropower station subject to excation，based on the discrete element theory,the numerical simulation of excavation of the underground powerhouse caverns was performed using PFC2Dsoftware.The influences of the controlling structural planes on surrounding rock mass deformation and failure were simulated,and the damage evolution law was reproduced.Moreover,a high resolution microseismic monitoring system was adopted to real time monitor and analyze the microseismic activity in deep underground caverns.Then the results of numerical simulation were compared with microseismic monitoring.The results showed that excavation damage zone of surrounding rock mass was closely related to faults,and the surrounding rock mass damaged regions obtained from numerical simulation was in good agreement with those revealed by microseismic monitoring.Therefore the approach of combining numerical simulation and microseismic monitoring was proven to be very promising for evaluating the excavation damage zones and predicting the potential instability of surrounding rock mass in the underground caverns subjected to excavation.关键词：underground group caverns;rock mass stability;numerical simulation;microseismic monitoring;partical flow code
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发布时间：2023-11-14 - 摘要：Abstract:In order to apply flaring gate pier to the bottom flow dissipation with low Froude number to enhance the dissipation energy,the energy dissipation mechanism and effect were researched through the combination of hydraulic model test and numerical simulation.The calculated result of numerical simulation was in good agreement with the result of hydraulic model test.It was shown that the incomplete flaring gate pier had little influence on the discharge capacity.Besides,the incomplete flaring gate pier did not increase the fluctuating pressure of stilling pool base slab,but increased the velocity gradient in stilling basin to achieve the effect of additional energy dissipation.So that the incomplete flaring gate pier was a meaningful reference to the arrangement of middle and small hydraulic complex.关键词：flaring gate pier;low Froude number;bottom flow dissipation;model test;numerical simulation
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发布时间：2023-11-14 - 摘要：Abstract:By using the roughness height conception developed by Cheng,a representative roughness height for loose packed sediments was developed.Then, the results were compared with the published experimental data and the coefficient inkv was determined.By drawing f-r/kvfigure,a new friction formula was proposed.The new relationship is useful for consolidating various measured data including the traditional open channel flow data.关键词：mountain rivers;Darcy friction factor;loose packed sediment;roughness height
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发布时间：2023-11-14 - 摘要：Abstract:Drop pit is a kind of bed form developed in rill erosion process,and it is the result from the interaction between rill erosion process and flow characteristics.Six slopes (2°,4°,6°,8°,10°,12°) and five discharges(8,16,24,32,40 L/min) were combined in erosion experiment.Results showed that the average depths of drop pit increased with the increase of slope while average spacing of drop pit decreased.The development coefficient of drop pit increased with the rise of slope,and it was ranged from 1.01 and 1.14 with a positive relationship with SP.With the same slope,the energy dissipation efficiency of drop pit showed a linear decrease trend with the increase of discharge,and it showed a power function increase trend with the rise of slope and SP.The energy dissipation efficiency ranged from 87.28％ and 98.58％.Research results showed that the development and mechanism of drop pit played an important role in flow characteristics and erosion sediment yield.关键词：drop pit;ladder deep pools;drop pit development coefficient SP;energy dissipation efficiency
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发布时间：2023-11-14 - 摘要：Abstract:To ascertain the vertical distribution of the matric suction in unsaturated soil by a source term’s 1D steady flow,a general solution was found with Gardner model.In addition,two particular solutions under the conditions of no source term and constant source term were also obtained,and the vertical distribution of the matric suction in unsaturated silt soil was analyzed under different surface flux boundary conditions and by different source terms.The results showed that the matric suction in unsaturated silt soil,when adopting constant source term,could be controlled with a specific discharge from the surface,a source term,a soil saturated infiltration coefficient and others.Under hydrostatic conditions,the matric suction and the distance from water table had a linear relationship.However,the relationship was non linear in non hydrostatic conditions.The specific discharge,when applying the constant source terms in the same direction of water flow,increased from the groundwater level to surface.Under the condition of evaporation,the matric suction by a constant source term was less than that with no source term at the same surface flow rate,whereas the result was the reverse when in the infiltration conditions.关键词：1D steady flow;source sink term;matric suction;vertical distribution;analytical solution
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发布时间：2023-11-14 - 摘要：Abstract:According to limitations of traditional reliability analysis on the identification of failure pattern of isolated bridges,a distinguish method based on IDA analysis and Weighted RSR method,combined with improved Park Ang damage model,was presented to estimate the statistical failure pattern of isolated bridges,which could provide a basis for the optimization of structural design.A finite element model for an isolated continuous bridge with six spans was developed within the environment of opensees,and then analyzed to obtain a statistic failure pattern.The obtained failure pattern was compared with the weakest failure mode of the isolated bridge.The weakest failure mode was optimized by selection of an optimal flexion weight ratio.The results showed that the isolation bearings on middle pears fail firstly,and all the bearings fail before piers.The optimal flexion weight ratio of this isolated bridge was 7%,which made the failurePGA increased by 0.05g.关键词：isolated bridge;damage model;failure pattern;IDA analysis;OpenSEES
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发布时间：2023-11-14 - 摘要：Abstract:Constrained least square method(LSM) was introduced to conduct three or more components hydrograph separation with stable isotopes considering that just one tracer was needed,while more than one independent tracers were required by end member mixing approaches (EMMA).Isotope hydrograph separation of Hailuogou glacier which lays the east edge of the Qinghai Tibet Plateau was analyzed as a case study.With isotope monitoring data(δ18O，δ18H),the application of the constrained least square method showed that approximately 73%,18%,and 9% of the stream flow was recharged by snowmelt,groundwater and precipitation,respectively.The results were similar to EMMA and previous studies.Through analysis,the new method reduced the uncertainty of EMMA when complementary tracer was added.Hence,the results could be used as a corroboration of other research methods关键词：hydrograph separation;least square method;stable isotopes;HaiLuogou Glacier;EMMA
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发布时间：2023-11-14 - 摘要：Abstract:For studying the difference of diffusive characteristics between mixture and uniform particles,sets of flume experiments were conducted.The trajectories of particles with different size were extracted under various particles and hydraulic conditions by using HD camera tecnology.Dxo Viewpoint was applied on image correction,besides,displacement datas of particles were extracted by ImageJ.The relationship between the variance of displacements and time from the data was analyzed.The results showed that,firstly,particles would present different diffusion characteristics at different time scales,for different hydraulic conditions and the ranges of particles.Secondly,the diffusion characteristics of mixture particles would always tend to be ballistic movement (β=2) on large time scale,which corresponded to a sorting phenomenon resulting from the heterogeneity of particle.Thirdly,the stronger the particle’s heterogeneity,the faster sorting phenomenon occured,and lastly in the nature rivers,sorting phenomenon would be more obvious due to the much more larger scale than flume experiments.关键词：mixture;bed load transport;tracing;ballistic;sorting
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发布时间：2023-11-14 - 摘要：Abstract:An energy dissipation model of “X shaped flaring gate piers + bottom flow dissipation” was put forward to the problem of low energy dissipation rate for small Fr value in stilling basin. X shaped flaring gate piers were placed at the water inlet of the stilling basin to disperse water flow and increase energy dissipation rate.Through the experiment, some hydraulic parameters were observed, including the water flow patterns,the depths of the water surface line along the stilling basin,the time average pressures,the pulsant pressure characteristics and so on.Experiments showed that the water flow forms a mode of “bottom flow +stretching flow in vertical +flow of jet”,the water flow fall into the stilling basin dispersely,which took full use of the interact water flow of each other.The lengths of hydraulic jump was 6.8 to 13.3 times to the different values of the initial flow depth and conjugate flow depth;the time average pressure on crest was toally change smoothly;the root mean square of the pulsant pressure was 0.03 to 0.18 times to the inlet water.Compared with the traditional stilling basin,energy dissipation rate improved 2 to 3 times.For small Fr value in stilling basin,“X shaped flaring gate piers +bottom flow dissipation” is a worth recommending method.关键词：stilling basin;X shaped flaring gate piers;bottom flow dissipation;energy dissipation rate
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发布时间：2023-11-14 - 摘要：Abstract:Based on GIS raster data model,the search method of the most dangerous three dimensional slope sliding surface with random search to determine the initial surface and pattern searh to determine the final surface was proposed.Combined with the search method,the program of slope stability with the analysis of 3D rigid body method was developed and verified by a numerical example to demonstrate the stability and rationality of program.The search illuminated that the search method not only avoided the situation that safety factor appears in local extremum in search progress of critical slip surface,but also improved the search efficiency of slip suerface and the program was highly accurate and stable.Furthermore,based on monitoring data of Shiziping Dam,the three dimensional stability analysis of the dam slope was carried out by the program.The search illuminated that the safety coefficient of dam slope was high under operating conditions and dam slope was in stable state.关键词：three dimensional rigid body method(slope3D SCU);joint search;three dimensional stability of dam slope;GIS platform
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发布时间：2023-11-14 - 摘要：Abstract:In order to bridge the semantic gap in automatic image labeling,and effectively leverage image features,two feature selection algorithms based on distance constraint sparse / group sparse coding (DCSC/DCGSC) were presented to solve the problem of image semantic labeling.Considering that feature atoms similarity may have different contribution to the semantic similarity between images,a distance constraint regularization was defined and integrated with sparse/group sparse coding for feature selection,which encourages the feature atoms with sparsity/group sparsity and more similar to the semantic discrimination to be enforced.Given a test image,the K Nearest Neighbors (KNN) can be found using the learned feature weights from the training images and labels can be transfered.Experimental results on Corel5K showed that DCGSC outperforms other related method with the average precision of 32%, average recall of 34%,and the numbers of total labels recalled of 151.For images represented with single type of feature,DCSC also helps to improve the annotation performance, which validates the effectivity of distance constraint for image labeling.关键词：automatic image labeling;distance constraint;sparse coding;group sparse coding;feature selection;K nearest neighbor
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发布时间：2023-11-14 - 摘要：Abstract:In order to improve classification performance and exploit label correlations,AdaBoost.MLR algorithm was proposed.Cosine similarity was adopted to capture the complex correlations among labels in AdaBoost.MLR algorithm,a supplementary label matrix was incorporated,which augments the incomplete original label matrix by exploiting the label correlations,label space was divided into three parts of label set,relevant label set and irrelevant label set,weight update rule was modified according to correlations among labels and the results of weak learner.AdaBoost.MLR algorithm was able to solve multi class classification problem specially,label similarity matrix,instead of cosine similarity,was constructed by the classification results of temporary strong learner combined by previous trained weak learners.The experimental results illustrated that the proposed algorithm was superior to existing algorithms,and the classification performance was improved significantly on datasets had complex correlations among labels.
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发布时间：2023-11-14 - 摘要：Abstract:Aiming at the pairing issue for flight plan which contains a airspace phase but without SSR(secondary surveillance radar) code,a novel method based on SSR code set for matching plan and track was proposed.Firstly,the boundary search algorithm was used to extract the contour of track,then for computing the matching confident factor the planned trajectory of flight plan was splited into route phase and airspace phase,and compared with the presettable threshold to determine the partnership between flight plan and track.At the same time,a novel time series classification learning method based on the trajectory of historical track was presented to deal with the issue of long term flight plan because of its property of invariance plan trajectory.The result of the application of a large scaled flow management system proved that the proposed algorithm can not only solve the pairing problems of the general flight plan,but also solve the flight plan without SSR code with a good adaptability.关键词：flight plan;pairing;SSR code set;contour of track;confidence degree of couple;classification learning
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发布时间：2023-11-14 - 摘要：Abstract:In order to provide interdisciplinary patent knowledge for designer in product innovative design process,a Chinese patent text classification method was proposed based on functional basis.Because functional basis has so many categories and the number of training sets for patent text is less,multiple binary classification algorithm and EM semi supervised learning algorithm were adopted to classify Chinese patent text.Compared with the results of naive Bayesian (NB) fully supervised classification experimental,by using the orthogonal experimental design,the selection of features and data sets were considered according to the accuracy of classification,the classifying accuracy rate of the first class reached above 80% which was in accordance with application requirements.This study provided core technologies for the construction of patent knowledge base based on functional basis in product innovative design system.关键词：innovation design;functional base;text classification;naive Bayesian;semi supervised learning
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发布时间：2023-11-14 - 摘要：Abstract:A method of multiple ontology mapping based on reference ontology,called MOM RO,was put forward.In the process of mapping multiple ontologies,MOM RO extracted the shared concept set from sets of source ontologies,and created a reference ontology.Then,the reference ontology was used to create a uniform vector space model (VSM).Then concepts in source ontologies were represented as vectors in the VSM.In this way,the similarity of concepts was calculated by the Euclidean distance of the corresponding vectors.Finally,the mappings among source ontologies were created.Experimental results indicated that MOM RO performs encouragingly well when creating mappings among multiple ontologies.关键词：ontology mapping;similarity;reference ontology;vector space model
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发布时间：2023-11-14 - 摘要：Abstract:In order to enhance the exploitation ability of the basic artificial bee colony (ABC),a rosenbrock ABC with elite region learning (ERABC) was proposed.The proposed ERABC utilized an enhanced search strategy with elite region learning to maintain the population diversity.Moreover,the rosenbrock’s rotational direction method was employed to improve the exploitation ability.The proposed ERABC was tested on 20 benchmark functions including unimodal,multimodal,and shifted functions.The effects of the improved strategy in ERABC were experimentally investigated.Furthermore,ERABC was compared with some state of the art ABC variants and several related evolutionary algorithms.The experimental results indicated that ERABC enhances the convergence speed and exploitation ability.〖关键词：artificial bee colony;elite region learning;search strategy;rosenbrock method
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发布时间：2023-11-14 - 摘要：Abstract:In order to deal with related images and non related images effectively in content based image retrieval (CBIR),a method of greedy learning based on optimum path forest classification(OPF),named as GL OPF,was proposed.Firstly,feature vectors of query images and the images in database were extracted by Gabor wavelet transform.Then,the relevance feedback of images was obtained by GL OPF active learning,generating training set of tags.Finally,prototype sets of relevance and unrelated were formed by further evaluation of OPF classifier of mark sets,and the most relevant query images would return after every iteration.The effectiveness of proposed method was verified by experiments on the three image databases Caltch101,Corel and Pascal.The experimental results showed that in eight iterations,the query precision of GL OPF rises more than that of other three methods.In addition,the running and query time of GL OPF is almost the same as that of OPF.关键词：content based image retrieval;optimum path forest classification;greedy learning;Gabor wavelet;relevance feedback
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发布时间：2023-11-14 - 摘要：Abstract:In order to solve the problem of the hard balance of the accuracy and speed in motion estimation of flotation surface bubbles,a fast motion estimation algorithm combined of bubble tracking and phase correlation technique was proposed.Firstly,the two continuous images in a sequence were preprocessed by zooming out on gray value minimum.Then the high gray value area of each bubble was extracted to complete the bubble tracking based on image segmentation method.Phase correlation was finally used to obtain the motion vectors of the bubbles.Block phase correlation method was further employed to obtain the detailed displacement feature for each block.Simulation results verified the estimation efficiency and accuracy of the proposed algorithm.Experimental results on a lead zinc flotation plant showed that the proposed algorithm can obtain real time motion vectors, and the detailed motion feature of each block can be obtained by the block phase correlation method.The bubbles motion data of each flotation cell showed the following characteristics.The bubble displacement motion of each flotation cell is in a certain cycle.The displacement motion distribution curve and the turbulence degree distribution curve of the same level flotation cell are the similar, and maintaining a certain degree of bubble movement turbulence can improve the grade of concentrate.关键词：Flotation;motion estimation;phase correlation;bubble tracking
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发布时间：2023-11-14 - 摘要：Abstract:Aimed at problems of feature redundancy caused by the fact that feature correlation was seldom considered in the feature ranking methods,a feature ranking model with redundancy control was proposed.Maximum discrimination ability and minimum redundancy of a feature subset were used as the objective functions of the very model so as to reduce the redundancy among features,and greed and non linear programming methods were employed to solve the model.Experiments were conducted on 9 public datasets and compared with feature ranking,and the result showed that the model can obtain a better classification accuracy and less feature size on most datasets.When non linear programming method is employed,the model can yield a feature subset,on benefit for determining the feature size.This model can be used when correlation exists among features.关键词：feature selection;feature ranking;feature redundancy;nonlinear programming
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发布时间：2023-11-14 - 摘要：Abstract:In order to solve underdamping oscillation of doubly fed induction generator (DFIG) aroused by grid fault,a flux damping control method for DFIG based on equivalent rotor voltage was proposed.State equation of the stator flux linkage was established.The oscillation frequency and damping ratio of stator flux linkage by means of solving the characteristic root was analyzed.The rotor voltage feedforward compensation with the addition of the stator flux linkage derivative feedback compensation could get equivalent rotor voltage reference.The mechanism about how to improve underdamping character of stator flux linkage and accelerate the speed of attenuation of transient flux dc component was proposed.The simulation results demonstrated that the proposed method suppressed the oscillation of the stator flux linkage and enhanced the DFIG voltage fault ride through capability.关键词：doubly fed induction generator;equivalent rotor voltage;underdamping;derivative feedback
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发布时间：2023-11-14 - 摘要：Abstract:In order to get an accurate and reliable model of the rise of temperature of connection fitting in value hall of UHVDC,a method of fuzzy system combined ant colony algorithm was used.After analyzing the characteristics of basic ant colony algorithm and gradient descent algorithm,an improved ant colony algorithm was put forward by combining basic ant colony algorithm and gradient descent algorithm,in which gradient descent algorithm was processed after basic ant colony algorithm. Through training data obtained from experiment,the fuzzy system was trained by basic ant colony algorithm,gradient descent algorithm and improved ant colony algorithm respectively.The convergence effect of improved ant colony algorithm was better than that of other two algorithms.All models were tested by testing data obtained from experiment,and the prediction effect of the fuzzy system trained by improved ant colony algorithm was best of all models.The prediction results showed that if training data obtained from experiment was enough,the fuzzy system trained by improved ant colony algorithm was reliable to predict the rise of temperature of connection fitting.关键词：connection fitting in value hall;fuzzy system;basic ant colony algorithm;gradient descent algorithm;improved ant colony algorithm
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发布时间：2023-11-14 - 摘要：Abstract:A new concept of hydrokinetic turbine using dual oscillating hydrofoils to extract energy from water currents(tidal or gravitational) was presented,which is particularly well suited for riverbeds and shallow waters near the coasts due to its rectangular extraction plane.The corresponding mathematical model and mesh model were established.A domain dynamic mesh strategy was used on fluid domain within sliding interface to make it move with the airfoil.The software Fluent was used to solve the turbulent flow around the airfoil.The influence of the reduced frequency,pitching amplitude and Reynolds number on the NACA0015 oscillating airfoil in aerodynamic characteristics and energy extraction performance was studied in the paper.Results showed that the reduced frequency,pitching amplitude and Reynolds number could influence boundary layer separation and vortex structure around the hydrofoils,affecting lift characteristics,drag characteristics,pitching characteristics and energy extraction performance.Reduced frequency and pitching amplitude had a greater influence on the time averaged power coefficient and energy extraction performance.With the reduced frequency of 0.14,pitching amplitude of 75° and Reynolds number of 5×105, the hydrodynamic and energy extraction performance could be better.The efficiency of energy extraction could reach 40%.关键词：dual hydrofoils;reduced frequency;pitching amplitude;energy extraction
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发布时间：2023-11-14 - 摘要：Abstract:For the problem of dynamic characteristic of aerostatic spindle,the finite element model considering the rarefaction effect was established.The modal and harmonic response of the spindle were analyzed.First,based on the finite element method to the spindle modeling,replacing the bearing with COMBIN 14 spring element,the stiffness of bearing and damp calculated under the rarefaction effects and traditional condition were served as the stiffness of spring,respectively.According to the actual working condition,the modal analysis in both cases were carried out.Then harmonic response analysis of spindle were also researched in the two situations to verify the results of modal analysis.Finally,Modal experiment of spindle by hammer exciting was performed to inspect the results of modal analysis and harmonic response.Experimental results indicated that the error of the first order natural frequency value of the spindle under the rarefaction effects is only 3.6% compared to the value of the test, while the error of the first order natural frequency value of the spindle under traditional scale is about 15% compared to the value of the test, which provides a certain basis for further optimization design and precision control of spindle system.关键词：aerostatic spindle;rarefied effects;modal analysis;dynamic performance
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发布时间：2023-11-14 - 摘要：Abstract:In view of the characteristics of parameter perturbation and uncertainty for drive system of hydraulic press,the mathematical model of drive system was established and a hybrid multi level robust control scheme that employed inner loop pressure tracking and outer loop velocity control was proposed.The outer loop velocity output tracking controller and prefilter were designed by using the Quantitative Feedback Theory.In the inner loop level,a nonlinear disturbance observer based upon radial basic function neural network was developed to track desired pressure with system uncertainties.Also,the ability of disturbance rejection for the disturbance observer was proved based on Lyapunov stability theorem.Simulation results show that the presented control strategy can improve the dynamic performance of the driven system and restrain the system uncer tainty evidently.Furthermore,the proposed approach is able to realize the smoothness with strong robust stability during the velocity switching transient period effectively.关键词：robust control;uncertain systems;disturbance rejection;quantitative feedback theory;hydraulic press;velocity control;Neural network
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发布时间：2023-11-14 - 摘要：Abstract:In order to improve the life of filtering reducer,a new structure is designed that gear tooth is slotted and tooth slotting is filled with red copper,hard aluminum alloys,nylon 1010 and nitrile rubber.Reducer finite element model (FEM) in different meshing locations is established based on a meshing model of planetary transmission with small tooth number difference,by which the meshing force in different engaging position is calculated.A mixed lubrication model is established by considering the roughness of tooth surface to calculate the lubrication status with different rotation speeds.The results of FEM analysis show that filler materials can increase the number of meshing pairs and decrease the meshing fore significantly.And maximum contact force decreases with the reduction of elastic modulus of filler materials.Lubrication calculation results show that filler materials can improve the lubrication performance effectively. Filler materials can increase the average film thickness in contact interface.The contact area ration is decreased by filler material when rotating speed is less than 1 500 r/min,as rotating speed exceeds 1 500 r/min,the decrease is not obvious.When speed is more than 1 500 r/min, Filler materials can reduce the maximum contact stress in engage in and engage out point,however,the variation of maximum contact stress is irregular with the variation of the elastic modul关键词：filtering reducer;fillers;meshing force;lubrication status;finite element model
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发布时间：2023-11-14 - 摘要：Abstract:In order to solve the problem that the magnetic field strength distribution in the working gaps is not uniform and the braking torque per 1 m3is small in magnetorheological (MR) transmission,a novel MR brake configuration featuring double layer gaps and several coils arranged along the circumferential direction were proposed.An exact closed form expression of the braking torque was derived,and the magnetic circuit modeling was established to estimate the magnetic field strength in the gaps.Then,BOBYQA method was used to optimize the structural sizes,and the magnetic field strength distribution was conducted.Simulation was compared with the calculation of magnetic circuit.The results showed that the magnetic circuit modeling can guide the structure design,and the torque per 1 m3generated by the designed MR brake is about 2.3×104Nm/m3.The research results provides a theoretical reference for the design of double layer multi coil MR brake.关键词：magnetorheological (MR) brake;multi coil;magnetic circuit;magnetic field strength;braking torque
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发布时间：2023-11-14 - 摘要：Abstract:In order to study the influence of the standing wave levitation stability with adding a resonant tube to ultrasonic standing wave levitation device,two ultrasonic standing wave devices model are designed.The combinations of the transmitter and the reflector in these two devices are concave concave and concave flat,respectively.And the two kinds of standing wave levitation way of the resonant tube and the non introduced tube are simulated and experimentally studied.The distributions of relative time average potential and relative acoustic levitation force in the two suspension ways are obtained by ANSYS and MATLAB co simulation,and the results show that the standing wave levitation stability can be improved by the introduction of the resonance tube whose radius is 1.023λ.Finally,the tests of liquid drops are made in the case of resonant tube and non resonant tube by setting up the experiment system,and the result show that the time of the levitation stability of resonant tube is longer than that of the non resonance tube when the liquid drop is suspended.Thus,the conclusion can be verified that introducing the resonant tube can effectively enhance the standing wave levitation stability in the ultrasonic standing wave levitation device in accordance with simulation result.关键词：standing wave levitation;simulation analysis;levitation stability;levitation force;resonant tube
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发布时间：2023-11-14 - 摘要：Abstract:Using Xe lamp light as experimental light source to imitate the sunlight illumination, the shrinkage temperatures(Ts)of fur products and toxic substances content were researched.Under the conditions of temperature 50 ℃,RH50% and irradiance(SI) 800 W/m2, some indicators of fur products were measured during the different lighting time,such as shrinkage temperature(Ts),Cr(Ⅵ),formaldehyde,phenol and aniline.Experimental results showed that the content of Cr(Ⅵ) and aniline increased in comparation with the content of formaldehyde and Ts values decreased as lighting time went on.In addition,the content of p关键词：Xe lamp light aging;shrinkage temperature;Cr(Ⅵ);formaldehyde;phenol;aniline
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发布时间：2023-11-14
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