最新刊期
卷 40 ， 期 5 ， 2008
- 摘要：Abstract:High and low of annual runoff is related to amount of annual runoff and its distribution in a year. The traditional annual runoff classification only takes into account of amount of annual runoff, and ignores the distribution of runoff in a year. In order to overcome the drawbacks of the traditional annual runoff classification methods, a new approach to runoff classification: Set pair analysis method (SPA), has been proposed in this paper. Both amount of runoff and its distribution in a year have been taken into account in the approach. The key of SPA method is to calculate the connective degree of the set pair which is constructed with the classification set of monthly runoff in a year and the standard set, A case study, the classification of annual runoff at a hydrological station of Jinsha River, has been researched. The results show that the presented method is concise and the results of classification are feasible.关键词：annual runoff classification;set pair analysis;degree of connection
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发布时间：2023-11-28 - 摘要：Abstract:The nonlinear dynamic model of a thermo-mechanical coupling viscoelastic rectangular plate with temperature field and subjected to both actions of an alternating periodic transverse external excitation and in plane uniform distributed force is established.The model,which talce into account of the influence of thermal conduction,is obtained by means of the constitutive description of thermo-viscoelastic material obeying the Boltzman’s superposition principle and the dynamic equilibrium equation of the rectangular plate on the basis of the Karman theory for thin plates with large deflection and the thermo-viscoelastic energy theory.It may be converted to a nonlinear differential integral dynamic system by using Galerkin’s method.The study indicates that:1) If the effect of heat expand and thermal conduction are ignored, the model can be reduced to the one of the viscoelastic plate；2) Letting the thermal conductive coefficient be zero and the heat expand coefficient being not equal to zero,the model is the same as the dynamic model of a viscoelastic plate with the influent of heat expand;3) If the effect of viscosity is ignored,namely,the model does not include the integral items,the model can be simplified to the thermo-mechanical coupling dynamic model of elastic plate关键词：viscoelastic plate;thermo-mechanical coupling;differential-integral dynamical system;nonlinear dynamic model
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发布时间：2023-11-28 - 摘要：Abstract:In this paper, the cracks situated along a straight line were investigated, and using complex stress functions, the stress intensity factors were formulated.For the two cases of only two collinear cracks and a single crack inside an infinite plate, the exact solutions of stress intensity factors were presented. Finally, by using the two collinear crack model and a single crack model, a new fracture criterion for brittle materials under compression was developed based on the traditional fracture criterion. In some special cases, this new crack propagation criterion can be simplified, and the results were very interesting, especially, for the case of materials without pre existing macrocracks, the new crack propagation criterion was identical with the well known Coulomb Mohr criterion.关键词：stress intensity factor;fracture criterion;crack surface friction;fracture toughness;two collinear cracks
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发布时间：2023-11-28 - 摘要：Abstract:A projection pursuit dynamic cluster model is developed, and it is used in water resources assessment for the first time.The projection pursuit dynamic cluster model combines projection pursuit principle with dynamic cluster method.Firstly,multifactor assessment problem can be converted into single factor (projected characteristic value) assessment problem according to linear projection.Secondly,a new projection index on the basis of dynamic cluster rule is constructed, which avoids the problem of parameter calibration in the assessment process successfully.In projection pursuit dynamic cluster model, the assessment results obtained from the characteristics of data set are more objective and less subjective.Finally,a case study of water resources assessment is conducted.A comparison of the water resources assessment for river basins along the coast of Liaoning Province shows that the results from the projection pursuit dynamic cluster model are reasonable and effective.The projection pursuit dynamic cluster model is a new method for water resources assessment and also a new approach to multi factor assessment.关键词：water resources assessment;indicator system;projection pursuit;dynamic cluster;projection index
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发布时间：2023-11-28 - 摘要：Abstract:Physics experiments on large scale uniform and non-uniform granular mixtures avalanche were carried out and the results proved that internal cause of SOC effect was most probably the structure characteristics of the system but not the size of granular or the scale of system. Furthermore, the stress transmission and stress distribution of uniform and non-uniform granular mixtures were simulated with discrete element method. According to the contrast between uniform and non uniform granular mixtures from three parameters of Shannon entropy, porosity and coordination number,it was found that the stuffing of granular matter in the non uniform granular system is more sufficient, so the system is more stable and it can show SOC. Meanwhile, there is no distinct difference of fractal dimension between the uniform and non uniform granular mixtures and thus the fractal could not be thought as the criterion of SOC.关键词：non-uniformity;Self-organized Criticality;granular mixtures;avalanche
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发布时间：2023-11-28 - 摘要：Abstract:Developing nationwide ecological restoration researches for soil and water conservation are proposed in China. In this paper, optimal conditions of ecological restoration were analyzed abide by the principle of heterogeneity, zonation, grade, conjugacy, primary factor and county land integrity. The special mapping database was developed, based on the raw materials of 2861 counties. With the application of GIS, choosing the key actors, such as climate, vegetation, soil, physiognomy, the types of soil erosion, and population density, the national area, except Tai Wan and maritime space, was divided into 4 first level ecological restoration domains and 14 second level ecological restoration regions by the way of adopting superposed analytical method and superincumbent partition method. Humid and Sem humid ecological restoration domains have better natural conditions for afforestation. Arid and Semi arid ecological restoration domains are only fit for afforestation in brush fire area.关键词：soil and water conservation;ecological restoration;principle;indices;regionalization
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发布时间：2023-11-28 - 摘要：Abstract:The constant downstream depth method of operation will be used by the middle route of the South-to North water diversion project, but the canal system operated by this method has a bad response and recovery property when combined with the downstream operation concept which is a demand-oriented operation. Combining discharge active compensation according to the real time downstream water demand and feedback control of the real time target water level, a new canal system operation method of constant downstream depth is designed. Based on canal hydraulics characteristics, a mathematical model of canal system operated by this method is constituted. As an example, the simulation of automatic operation of the emergency sector of the South to North water diversion project is carried out and the results show that the operation of this new method has a good response and recovery property,thus overcome the incompatible problem between the traditional constant downstream depth method and demand oriented operation concept.关键词：downstream operation;constant downstream depth;discharge active compensation;South-to-North water diversion project
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发布时间：2023-11-28 - 摘要：Abstract:Soil erosion is a very complicated physical process and its physical mechanism is very complex so that it is difficult to describe by mathematical expression. Compensatory fuzzy neural network (CFNN) is a complex system of compensatory fuzzy logic (CFL) and artificial neural network (ANN). It has higher systematic stability and error tolerance. Base on the dynamic and physical behavior of soil erosion, the present paper modified the CFNN to predict soil erosion on slope land. MATLAB computer program had emulated using the observed data at somewhere Station of Water and Soil Conservation in Sichuan province. The system error was 0.0517, and difference between predicted and the observed values was less than 10%. The results indicate that the modified CFNN is much more precision than traditional artificial neural network. It provides a vital tool for soil erosion modeling and predicting.关键词：compensatory fuzzy neural network;soil erosion;slope
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发布时间：2023-11-28 - 摘要：Abstract:There is obvious difference of transport mechanism between the uniform and non uniform sediment, in this paper, the incipient motion of non-uniform sediment is theoretically studied, based on the method of probability theory combined with mechanics, the mean of sediment particle’s force arm and the expression for the probability of incipient motion with shelter-exposure effects to be considered are derived. There is a discontinuity point in Han’s fine sediment distribution function, based on the sediment motion mechanism and L-S integral property, author bears out that it does not influence the mean of force arm. Once the incipient probability is built, the incipient velocity can be determined. From the experiment for the incipient motion of non uniform sediment with colored sand conducted by Han, the coefficients in the computational formula are determined. Verifications with Han’s experiment data show that the theoretical formula is better than Han’s. The computed results fully reflect the characteristics of threshold motion of non-uniform sediment.Finally the formula of uniform sediment is established, as a special case.关键词：relative exposure degree;force arm;L-S integral;incipient probability
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发布时间：2023-11-28 - 摘要：Abstract:Based on Biot’s consolidation theory seepage-stress coupling field is computed to investigate the influence of the seepage and the entity mixed model is improved,considering the hydraulic exchange between the structural plane and the rock mass in normal direction, in which the variation of steel stress is used to reflect the change of stress state in the structure. Then sensitivity analysis is done to investigate the maximum water pressure acting on the exterior surface of tunnel liner considering influencing factors such as the crack width in concrete of tunnel liner, the permeability of surrounding rock and the occurrence of structural plane in rock mass. The analysis results reveal that the tensile stress of rebar decreases in the coupling analysis step. It is also found that the maximum water pressure acting on the exterior surface of tunnel liner is the most sensitive to the crack width and insensitive to the occurrence of structural plane. But the occurrence of structural plane has great effect on the distribution of water pressure.关键词：hydraulic tunnel;seepage-stress coupling field;Biot’s consolidation theory;sensitivity analysis;structural plane
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发布时间：2023-11-28 - 摘要：Abstract:Different expressions were proposed for the computation of dissolved gas levels in the stilling basin and the river. Through high speed jet test and the device designed by authors TDG generation processes was analyzed deeply. It was found shows that the huge energy takes air bubbles into the bottom of the stilling basin during spill release, which makes air solubility increase along the depth of stilling basin,therefore the water in the bottom of the stilling basin can dissolve more gas than surface. Through strong turbulence in stilling basin the water with high concentration TDG mixes with the low concentration water, so dissolved gas in the part of water in stilling basin become supersaturation. It was also found that the velocity of supersaturation TDG increase with the levels of disorder without aerating.关键词：total dissolved gas;supersaturation;saturation;shot flow;turbulence
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发布时间：2023-11-28 - 摘要：Abstract:The properties of concrete are greatly influenced by tunnel fire.Therefore, based on ISO834 fire curve, compressive experiments were conducted to study the compressive strength variations with increasing temperatures up to 700 ℃, and the formula which shows the coupling correlation between compressive strength and temperature variation based on standing time was established.Then microstructural observations of the concrete specimens by means of scanning electron microscopy (SEM) were obtained. Results showed that the compressive strength gradually decreased with increasing temperatures. These test results can be used for accurately analyzing and investigating the behavior of concrete with different temperatures, cooling modes and standing time.关键词：Tunnel fire;fire curve;concrete;compressive strength
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发布时间：2023-11-28 - 摘要：Abstract:Abstract: In order to prepare the pavement concrete with freeze-deicing salt resistance, the freeze-deicing salt resistant agent (ASN) was researched and developed. According to the CDF test method, the freeze-deicing salt resistance of the pavement concrete with ASN agent was studied. The results showed that the scaled mass of ordinary performance concrete decreased by 56%, the dynamic modulus of elasticity loss rate decreased by 68% and the scaled mass of high performance concrete decreased by 75%, the dynamic modulus of elasticity loss rate decreased by 42% after 56 cycles due to the freeze-deicing salt resistant agent added into the concrete. Scaling mark on the concrete surface was hardly detected. SEM demonstrated that microstructure of concrete was dense and micro-cracks did not occur. So the ASN agent can greatly improve the pavement concrete in freeze-deicing salt resistance.
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发布时间：2023-11-28 - 摘要：Abstract:The method of grey relational entropy was used to analyze the phosphorus release in the anaerobic zone of the SUFR system. The results showed that the rotational speed，the pitch angle of the guiding vane，d/D， and the layers of multistage vane play important roles in the anaerobic zone. The decreasing effect sequence of the four factors is: the rotational speed＞the pitch angle of the guiding vane＞the layers of multistage vane＞d/D. This method was useful to the practical operation of the SUFR system in the Three Gorge Reservoir Region.关键词：spiral up flow reactor;phosphorus release under anaerobic condition;parameters of the guiding vane;grey relational entropy
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发布时间：2023-11-28 - 摘要：Abstract:Polyarylene sulfide sulfone (PASS) belongs to a new generation of heat resistant engineering thermoplastics and has already been used as an excellent membrane material. The preparation of PASS separation membrane by means of immersion precipitation method (L-S method) and the phase diagram of the PASS/solvent/non solvent system were studied. Solubility order of the solvents to PASS according to ternary phase diagrams is NMP>phenol/tetrachloroethane>DMF. Precipitating ability of non solvent is H2O>glycerine> glycol>isopropanol>grain alcohol>1, 2-propaanediol in order. The prepared membrane has unsymmetrical structure which contains a thin porous layer and a thick support layer with finger like bores. The formation mechanism of the finger like bores is attributed to the delay in the phase separation of the cast solution.关键词：polyarylene sulfide sulfone (PASS);membrane;phase diagram;morphology
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发布时间：2023-11-28 - 摘要：Abstract:To analyze the fire resistance of the prestressed structures at high temperature, 27 steel strands members were tensioned at high temperatures. The mechanical properties such as stress-strain curve, yield strength,tensile strength, modulus of elasticity of steel strand at high temperatures and its mechanics models were obtained. The material model can be used to analyze prestressed structure’s response at elevated temperature. At last, the application scope of material model was declared.关键词：high temperature steel strand material property material model
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发布时间：2023-11-28 - 摘要：Abstract:Using powder metallurgy technique, the TiC/Fe matrix composite was fabricated in situ. The microstructure of the composite was investigated using X ray diffraction(XRD) and scanning electron microscope(SEM). The differential thermal analysis (DTA) and high temperature X ray diffraction were applied to study the reaction principle of the Fe Ti C system. The wear resistance of TiC/Fe matrix composite was examined on a MM 200 wear test machine. The results showed that the synthesized composite consists of fine TiC particles, Fe3C andα Fe as the binder phase. TiC particles exhibit fine size and homogeneous distribution in the matrix.The reaction principle is as follows: first, allotropic changing α Feγ Fe at 765.6 ℃; secondly, the formation of compound Fe2Ti at 1078.4 ℃ through the eutectic reaction between Ti and Fe; thirdly, thereaction between carbon and melted Fe2Ti causing the formation of TiC at 1138.2 ℃. Under the condition of dry sliding with heavy loads, TiC/Fe matrix composite shows better wear-resistance.关键词：in situ synthesis;TiC/Fe matrix composite;microstructure;reaction principle;wear resistance
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发布时间：2023-11-28 - 摘要：Abstract:Polymer-matrix giant magnetostrictive composites were prepared by combining Tb0.30Dy0.7Fe1.95 / epoxy and making use of home-made and simple compression molding device. The bonding process and the structure of the molding device were introduced. The properties of the composites were studied. The microstructure, density, high-frequency responsing property, mechanical property, magnetostriction and compressive stress effect were characterized by the scanning electronic microscope (SEM), Archimedes displacement method, Agilent 4294A dynamic impedance analyzer, YE-300 type of electronic universal testing machine, standard strain gauge technique respectively. The results show that the composite had many advantages such as homogeneous and compact microstructure, low porosity, high magnetostriction, good property reproducibility and so on. The raw materials were not ejected out off the mould chamber during the molding process. The magnetostriction of the composite was 820×10-6 and 1006×10-6 respectively when 0MPa and 1MPa preload-stress was applied. And the composite had higher cut-off frequency. The preparation method had lots of advantages such as low cost, simple device and process and high properties and so on, and appropriate for industrial applications. The property improving mechanism of the composites was explained.关键词：bonding;giant magnetostrictive materials;molding device;preparation process;property
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发布时间：2023-11-28 - 摘要：Abstract:In order to solve the problem that Gene Expression Programming (GEP) has not still turn up trumps to the mining rapidity and precision of RFID and Economy Statistical Time Sequence Data in symbol regression and class domain, the definition of Statistical-Gene, Statistical-Chromosome, Statistical fitness and the integration amelioration to traditional GEP time Sequence model were proposed. The novel mining algorithm of single-variable and multi-variable time sequence mining algorithm were given to heighten the mining rapidity and precision of GEP economy time sequence model. The effectiveness of new algorithm was demonstrated by extensive experiments and the result showed that the mining rapidity of multi-variable time sequence mining algorithm was rapidness and the forecast precision was heighten up 5% compared with traditional GEP and single variable GEP time sequence mining algorithm. New algorithm was appropriate for RFID and other economy system as well.关键词：economy statistical time sequence forecast model;single-variable GEP time sequence;multi-variable time sequence;Gene Expression Programming function mining
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发布时间：2023-11-28 - 摘要：Abstract:In order to improve the survivability of the database, a remote backup method(MMDRB) was presented. The local database was monitored in real time, and the data changes of it were encapsulated into records, which were put into a mass buffer. Then, records in the mass buffer were sent to several remote one-level databases asynchronously, and the data changes were replayed on the remote one-level databases. And also, the data changes of the remote one-level databases were monitored and replicated to several remote two-level databases. The multi-point and multi-hop remote backup of the local database was achieved. The proposed method had the features of multi-point and multi-hop backup, good real-time capability, fine backup granularity and low network requirement. The theoretical analysis and the experiment results showed that this method was a new good approach of database remote backup.关键词：disaster backup, disaster tolerance of database, remote replication, asynchronous replication
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发布时间：2023-11-28 - 摘要：Abstract:In order to solve the user anonymous authentication problem in mobile IP registration, a mobile IP registration protocol with user anonymous authentication was proposed. Using the Diffie Hellman key exchange scheme, the mobile node (MN) generates the dynamic session key shared with the home agent (HA). MN encrypts the MN’s real identity with the session key to construct its temporary identity (TID) in the registration request message; HA decrypts the received TID to get the MN’s real identity. The user anonymity and location moving untractability are achieved due to the dynamic TID. The asymmetric and symmetric cryptography are employed for mobile entity authentications. Theoretical analysis demonstrated that the proposed protocol accomplishes both strong anonymity and mutual authentication among three mobile IP entities. Compared with the anonymous wireless authentication protocol proposed by Peng et al., the proposed protocol reduces the computation load at the MN.关键词：mobile IP;anonymous authentication;registration
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发布时间：2023-11-28 - 摘要：Abstract:A method of multi-channel support for DMAC in WSNs was propossed.The channel assignment was based on the local information of nodes. The multi-channel DMAC protocol implemented channel distribution before message collecting from source nodes to sink node and made broadcasting possible in DMAC. Analysis and simulation result showed that this multi-channel protocol decreases the latency without increasing energy consumption.关键词：multi-channel;low latency;energy efficiency;MAC;WSN;DMAC
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发布时间：2023-11-28 - 摘要：Abstract:An important problem before the parameters identification of biological inverse problems, that is, the determination of the position of measuring points,was discussed.The Bayesian theory was applied to define the probability of the samples by the posterior probability of the undetermined parameter and the information entropy was used to describe the measured information.The “contribution” of different measuring points was expressed by the evaluation factor that was defined by information entropy.The calculation result of single species biological model showed that the tendency of reconstruction error of the undetermined parameter can be reflected by the evaluation factor that could also describe the contribution of every measuring area.关键词：inverse problems;information entropy;bayesian method;evaluation factor
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发布时间：2023-11-28 - 摘要：Abstract:he Turbo-BLAST detection can effectively cancel the spatial interference from the conventional V-BLAST (Vertical Bell Lab’s Layered Space Time) system. On the basis of analyzing the algorithm principle of Turbo BLAST,the performances of serial Turbo-BLAST system and parallel Turbo BLAST system were researched and compared over quasi-static Rayleigh fading channel.Meanwhile,their suitable application situations,existing shortcoming and improvement in need were also pointed. The simulation results showed that the serial Turbo BLAST system is better than parallel Turbo-BLAST system under same spectrum efficiency,whereas the latter can be used for adaptive transmissions.关键词：Turbo-BLAST;iterative detection;interference cancellation;minimum mean square error;Soft Input Soft Output(SISO);Multiple-Input Multiple-Output(MIMO)
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发布时间：2023-11-28 - 摘要：Abstract: To enhance stability of the MANET network with hierarchical structure and reduce the cost for calculation and communication, an improved weight-based clustering algorithm is proposed. According to the algorithm, the energy and motion of the nodes are considered, and the comparative average velocity is adopted as the most weight so as to enhance the stability of the clustering architecture and reduce the cost of clustering maintenance and improve the operating efficiency of the network. The simulation tests proved the effectiveness of this approach.关键词：MANET,Clustering Architecture,Clustering Algorithm,Weight
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发布时间：2023-11-28 - 摘要：Abstract:Conventional KNN (K-nearest Neighbor) algorithm requires large computational consumption when training samples are large. To address this concern, a novel immune-based data reduction approach was proposed and applied to solve color recognition of license plates. Antigenic determinant, immune cells, etc, were defined and computational method of affinity was given. In the process of multi-species parallel learning, clone selection and mutation, immune tolerance, immune memory and other mechanisms were employed to implement data reduction on each training antigen set. Then the reduced representative detectors were used to perform color recognition of license plates during the second immune response stage, integrated with KNN approach. Experiments were conducted on two data sets, compared with three data reduction approaches based on histograms,and results showed that the proposed algorithm can perform data reduction task effectively, with the reduction rates of 98.87% and 95.48%, respectively,and the overall accuracies of 97.45% and 94.73%,关键词：data reduction;Artificial Immune System (AIS);color recognition;KNN
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发布时间：2023-11-28 - 摘要：Abstract: In order to improve the performances of particle swarm optimization（PSO）on convergence rate and accurate, a hierarchical structure poly-particle swarm optimization（HSPPSO） approach using the hierarchical structure concept of control theory was presented. In the bottom layer, parallel optimization calculation was performed on poly-particle swarms. In the top layer, each particle swam in the bottom layer was treated as a particle of the single particle swarm. The best position found by each particle swarm in the bottom layer was regard as the best position of single particle of the top layer. The result of optimization on the top layer was fed back to the bottom layer. If some particles trended to local extremum in PSO algorithm implementation, the particle velocity was updated and re-initialized. The test of proposed method on four typical functions showed that HSPPSO performs better than PSO both on convergence rate and accurate solutions. The HSPPSO proposed in this paper provided a new idea for large scale system optimization problem.关键词：Poly-Particle Swarm;particle swarm optimization;Hierarchical Structure;Evolutionary Computation
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发布时间：2023-11-28 - 摘要：Abstract:Contraposing the distance between the theoretic correcting capacity and the actual correcting capacity of TPC, on the base of studying the encoding and constructing methods of the TPC, this paper analysed the theoretic correcting capacity and the actual correcting capacity of TPC，and indicated that if the two component codes had error-correcting capacity t, the TPC had error-correcting capacity (t+1)2+t. An improved iterative decoding algorithm which could be used after usual decoding algorithms to improve the decoding performance was brought forward，and it can correct some errors which usual decoding algorithms could detect but could not correct. The simulation result showed that the improved iterative decoding algorithm could lower the BER, especially when the SNR was low.关键词：Turbo product code;Correcting capacity;Improved iterative decoding algorithm
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发布时间：2023-11-28 - 摘要：Abstract:In order to effectively classify mechanical components in embedded system, a novel method was proposed to extract edge features of mechanical component images since mechanical components have comparatively obvious edge features. First, the Kirsch operator was used to extract the edge of mechanical component binary image. Then the edge image was divided into several areas with the centroid as the center, and the modified normalized central moments of each area were calculated. The vectors including these central moments were constructed to be the edge features of mechanical components. In the experiments, the means clustering algorithm was used to classify the components based on the extracted edge features, and the effectiveness was proved by the results.关键词：mechanical components image;edge feature;central moment;means clustering algorithm
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发布时间：2023-11-28 - 摘要：Abstract:In order to improve the measurement accuracy of pulmonary function and reduce clinical diagnosis errors of respiratory diseases，the precision controlled lung simulator was used for pulmonary lung function measurement calibration. The lung simulation device’s basic structure and principle, the method of calculating gas volume, and work mode were described. The volume errors on flow linearity and all kinds of work mode was studied. The spirometer was calibrated by the lung simulator and its volume relative errors were less than 3.5% for the flow linearity and vital capacity and forced vital capacity, less than 2% for minute ventilation and less than 10.5% for maximum voluntary ventilation. Based on the test data and the analysis, calibrated pulmonary function test values were within the ATS and ERS standards, and this reaches on calibration purposes for the spirometer. Experimental study of lung simulator application provides reference for the extensive use of lung simulation devices. It is the first time in domestic metrology to provide quality control, measurement calibration and traceability for the spirometer device.关键词：lung simulation device;spirometer equipment;respiratory pattern
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发布时间：2023-11-28 - 摘要：Abstract:A rotatable wheeled mobile robot applied in special rough environment, such as climbing slop and turning a somersault was stadied. The climbing capacity and the dynamic modeling of turning state were analyzed. Some factors affecting the maximum angle of climbing slop were obtained. The dynamic modeling of turning states was inferred by Alembert Principle. Some parameters are analyzed combining driving ability. The robot’s condition of overthrow and reset was gained. The designing the wheeled mobile robot, which can run successfully in a complicated environment, and developing its adaptability关键词：mobile robot;rotatable;climbing slop;dynamic modeling
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发布时间：2023-11-28 - 摘要：Abstract:Different hydraulic servo control system would be obtained through changing load based on cylinder controlled by servo valve.Load pressure-flux characteristics of asmmetrical cylinder controlled by servo-valve was analyzed. Flux continuity equation of cylinder controlled by servo valve and the balance equation of hydraulic cylinder were pat fprward,The dynamic characteristics mathematics model for position control system in cylinder controlled by servo-valve was deduced .SIMULINK module of MATLAB language software was used to carry through dynamic characteristics simulation analysis for position control system in cylinder controlled by servo-valve.The results were validated through experiment，and showed that mathemati model and simulation results were closed to practice work situation,and could satisfy analysis needs to different hydraulic servo control system load characteristics关键词：hydraulic servo control;cylinder controlled by servo-valve;mathematics model;MATLAB;simulation
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发布时间：2023-11-28
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