最新刊期
卷 41 ， 期 2 ， 2009
- 摘要：Abstract:In order to make data communicate mutully between optical software and FEA software,data processing and transformation algorithm between optical and mechanical analyses were given in optical-mechanical system. Zernike polynomials were used as interface tools. On the basis of the study on Zernike fitting process, a visual optical-mechanical interface process was developed. All functions in the program were explained. A reflect mirror in the telescope was taken as example. The optical/mechanical analysis was made at last. The results proved the effective and extensive performance of the interface program.关键词：optical-mechanical;integrated anlysis;Zernike polynomials;optical-mechanical interface
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发布时间：2023-11-28 - 摘要：Abstract:The Set Pair Analysis (SPA) has been introduced into the relation analysis of hydrological variables.The connection degree of SPA can display the detail related structure of hydrological variables,the property and ratio of all relations from the related structure have been probed. Based on the above results,an approach of selecting main impact factors of depended hydrological variable has been suggested,which was applied to the analysis of runoff regressive function.The case studied results showed that the relation analysis of hydrological variables based on the set pair principle is more effective,impersonal and reasonable than the relation coefficient.It can be applied to the science of hydrology and water resources.关键词：relation analysis of hydrological variables;set pair analysis;recognition of impact factor;connection degree
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发布时间：2023-11-28 - 摘要：Abstract:As a discontinuous media element,contact surface element is commonly used to simulate discontinuous deformation between different medium and the tangential stiffness coefficient will have great effect on results of numerical computation.Taking concrete impermeable wall as research object, Duncan Chang nonlinear elastic soil model and Goodman contact model are introduced. Through different values of tangential stiffness coefficient,finite element method is used to study distribution laws of deformation and stress of impermeable wall.Research results show that compressive and tensile stress will be lowered when tangential stiffness coefficient is reduced, thus stress state of impermeable wall will be improved and abrupt change of stress between overlay and rock layer will be minished, which is propitious to unleash performance and safety of impermeable wall.关键词：foundation pit;slurry;impermeable wall;contact element;tangential stiffness coefficient;sensitivity analysis
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发布时间：2023-11-28 - 摘要：Abstract:This paper is the study on velocities of the flow in straight channel with emergent, rigid vegetation. The flow is assumed to be steady and uniform. The vertical profiles of stream wise velocities are simulated using a new model which is based on the mixing length concept, given by analyzing the relevant forces acting on the volumetric element surrounding the considered vegetation elements. This model fully takes into account the vegetation group’s influences on the mixing length，drag coefficient and Darcy Weisbach friction factor. Great advantage of the model are that the physical concept is clear，the form is simple, and the friction velocity can be evaluated directly. The numerical simulations have been tested against the data obtained experimentally by this paper and Rowinski respectively with emergent，rigid vegetation. The results indicate the new mixing length model in this paper is effective and reasonable.关键词：vertical velocity distributions;emergent vegetation;the mixing length;friction velocity
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发布时间：2023-11-28 - 摘要：Abstract:In the study, the mechanism of Eutrophication generation in Three Gorges Reservoir is theoretically analyzed. One dimensional hydraulic and eutrophication model based on the Xiangxi branch is developed and the influence of the hydrodynamic condition on algae primary birthrate based on the model is researched.Comparisons of the factors of TP、TN、chla along the branch in the spring,2005,with experimental data indicate that the simulated results behave well,especially, the results of TP、TN were better than those of chla.Much higher chla in the reservoir anabranch than in the upstream shows the evidence of algae breaking out.The developed model can be used to predict the distribution of Eutrophication in similar Channel Type Reservoirs.关键词：channel-type reservoirs;eutrophication;reservoir operation;developing model
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发布时间：2023-11-28 - 摘要：Abstract:In order to clarify the mechanical characteristics on friction reduction by coupling flexible tubes with turbulent flow,experimental investigation was performed on effects of turbulent drag reduction by using sleeve structured flexible tubes.The speciality of pressure fluctuating on inner wall surface of the flexible tubes and the speciality of the displacement fluctuating on the external wall surface are studied, by using the strain gauge and pressure sensor. The results are as following. The thinner the flexible tubes and the bigger the Reynolds numbers, the bigger the turbulent drag reduction rates are, and at the Reynolds numbers of about 18000, the rates of drag reduction of the sleeve structured flexible tubes with thickness of 2 mm, 3 mm, 4 mm are about 12%, 10%, 9%. The intensity of the pressure fluctuation on the inner wall surface is greatly weakened in comparison with the rigid tube, the displacement fluctuation phase on the outer wall surface of the tubes is the same as the pressure fluctuation on inner wall, so the greatly weakened intensity of pressure fluctuation can be supposed to be the main cause of drag reducing.关键词：flexible tube;turbulent friction drag reduction;fluctuating pressure;fluctuating displacement
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发布时间：2023-11-28 - 摘要：Abstract:For studying cumulative effects to water temperature of diversion cascade plant, the water temperature distribution of every cascade plant were predicted using the vertical one-dimensional water temperature model and warming rate in this paper. By analyzing the forecasting result, three forms of cumulative effects to water temperature were gained, namely (1)Operation of first reservoir changed downriver water temperature distribution, induces water temperature delay phenomena: In the spring warming postponed, In the autumn cooling delayed. The water temperature delay phenomenon was transferred by diversion, so the water temperature delay phenomena of downriver cascade plant was more obvious. (2) Water temperature of plant tended to flat. Flat phenomenon of water temperature in the plant became more obvious from first cascade to last cascade. (3)Longitudinal water temperature change was reduced. The results provided scientific foundation for environmental impact assessment of river basin development.
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发布时间：2023-11-28 - 摘要：Abstract:In order to solve the problems of high velocity near bottom, unstable flow pattern, in conventional stilling basin, based on physical model test of the Qingshanzui Project in Chuxiong, Yunnan, China, a new type of stilling basin -- Stilling Basin with Shallow-water Cushion (SBSC) was proposed, and its hydraulic performances such as the flow pattern, velocity distribution, pressure distribution on bottom and energy dissipation have been studied through the model experiment. The experimental results indicated that the SBSC is favorable for decreasing the velocity near bottom, changing the flow pattern and improving the hydraulic performances in the stilling basin, so that it can stabilize the flow pattern and increase the rate of energy dissipation. The SBSC is of high energy dissipation rate with a low construction cost comparing with the conventional stilling basin.关键词：stilling basin with shallow-water cushion;hydraulic performances;Energy dissipation
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发布时间：2023-11-28 - 摘要：Abstract:The correlation of wet and dry year of runoff between the water-exporting and water-importing area of western route south-to-north water transfer project was analyzed by SPA ,with description of identical, discrepancy and contrary to wet, normal and dry year. The results showed the connected structure is reasonable between sets and more than ten years’ cycle and quqsi-3 years cycle of runoff exist in the water-exporting and water-importing area . Each hydrological station among water-exporting and water-importing area keeped close correlation with wet, normal and dry year respectively. Adjustment reservoirs will be laid out in somewhere of water-exporting and water-importing area in order to rationally reserve abundant water and reduce unfavorable impact on lower reaches of the water-exporting rivers. Set Pair Analysis ( SPA) is an effective and new way to deal with the uncertainty problem.关键词：western route of south-to-north water transfer project;set pair analysis;runoff encountering analysis
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发布时间：2023-11-28 - 摘要：Abstract:ABSTRACT：During carrying on the energy-saving and emission-reduction policy, actively studying the mode of energy generation scheduling optimization has been widespread concern on the power department. Hydraulic coupling between hydropower plants, time of delay with downstream flow and possible factors such as wasting water, must take into account in the optimal scheduling of cascade hydropower plants containing hydro and thermal electric plants. Present a multi-objective model considering environment protection and saving energy. This model takes total operation costs of thermal power plants, contaminative gas emission and spilling water of hydroelectric power plants as optimal objectives. Solve this problem with heuristic agent method. The simulation results show that this proposal model increases generation benefits of hydroelectric power plants, reduces operation costs of thermal power plants, advances comprehensive benefits of power systems, and provides a novel research thought for hydrothermal power systems short-term optimal scheduling problems.关键词：energy-saving and emission-reduction;generation dispatching;hydro and thermal electric plants;agent
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发布时间：2023-11-28 - 摘要：Abstract:As a new fashion river regulation building, the effect of pile permeable spur dike to flow and bed needed dependable quantitative research. Based on previous research, and combined indoor experiment, the characteristics of flow nearby pile permeable spur dike and the local scour were analyzed. The local water head loss of permeable spur was considered of superposition which included the water head loss of the current through spur like a water screen and the water head loss of main current cross section extending suddenly. The energy equation was built up based this, and the calculation formula for backwater height of the permeable spur was obtained. Based on this research, through the association theory analysis and experiment, this problem of scour depth was discussed in this paper. Superposed model of flow nearby spur was built firstly, and then the formula of spur head flow velocity distribution is derived. At last, a theory formula of scouring depth around 900 pile permeable spur dike was built. These formulas had explicit mathematical modes and physical conception, and the calculated result fitted the experiment data well. All the researches above could supply technical grounds to the design.关键词：permeable spur dike;backwater height;scouring depth;pervious rate
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发布时间：2023-11-28 - 摘要：Abstract:Based on the result of regionalization of Ecological Restoration in China, each of ecological restoration Region was given a full consideration for its characters of soil erosion, social economy and physical geography conditions by using the data bases of national country (2861 counties). Based on the analysis of the suitable conditions,the different emphasis of the different regions for ecological restoration and the relevant restore measure were put forward. According to the different feasibility ecological restoration types, and based on the analysis of typical successful and fail examples of ecological restoration, it was concluded that only based on the respect for principle of the zone, combining natural restoration and manual measures by the ecological restoration area division is the better way to exert the ecosystem’s ability of self organizing and self corresponding, speed up the restoration of degradation ecosystem.关键词：soil and water conservation;ecological restoration;regionalization;measures
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发布时间：2023-11-28 - 摘要：Abstract:The problems of “curse of dimensionality” will be resulted from the application of stochastic dynamic programming(SDP) to the optimization operation of a multi reservoir system and it is difficult to apply SDP to multi annual regulating reservoirs. A multistage decomposition combination optimization method(MDCOM) is presented to the optimal operation of multi reservoir system, which contains a SDP operation measure with even release flows for the multi annual regulating reservoirs. The method decomposes the optimal operation problems of multi reservoir system into the optimization operation of each single reservoir with SDP in the first stage. An improved genetic algorithm simulated annealing hybrid algorithm is proposed to combine and optimize the results of the each single reservoir in the second stage. In a case study of long middle term optimal operation on generation electricity of a 3 reservoir system in series in Wujiang River, Guizhou Province, a mean annual generation electricity of 9.472 billion kW·h for the multi reservoir system is achieved, which is bigger than that from GA, SA or SDP applied respectively. The MDCOM also runs faster than the SDP. The results obtained from these applications have proved that the MDCOM is a new promising search algorithm for multi reservoir optimization problems.关键词：optimization operation of multi reservoir system;multi annual regulation reservoir;stochastic dynamic programming;genetic algorithm simulated annealing hybrid algorithm
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发布时间：2023-11-28 - 摘要：Abstract:In this article, according to the characteristics of the comprehensive ultilization reservoirs and the water users, a multi objective optimization mathematical model for comprehensive ultilization of reservoirs is established, and the method based on group decision making theory for solving this model is presented. The method transfers the multi objective optimization into a number of single models constituting the no inferior solution set of the model, and then obtains the best satisfied solution from the no inferior solution set with group decision making theory.The model and the method were applied in the optimal operation of ZiPingPu reservoir in Sichuan, and the results are satisfactory.关键词：reservoirs;optimal operation;multiobject;group decision making
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发布时间：2023-11-28 - 摘要：Abstract:Abstract: A semi-analytical and semi-numerical approach for earthquake induced interior hydrodynamic force on rectangular hollow bridge pier was developed. Based on linear radiation wave theory, eigenfunction expansion method was used to format the potential of rigid movement and that of elastic vibration. Then interior hydrodynamic forces were got. The coupling kinetic equations were solved by FEM with beam elements. This method is a relatively simple and efficient approach Examples were presented to discuss the influence of earthquake induced interior hydrodynamic force on rectangular hollow pier. The results illustrated the accuracy of this method.关键词：rectangular hollow bridge pier;earthquake;interior hydrodynamic force;linear radiation wave theory
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发布时间：2023-11-28 - 摘要：Abstract:Rock failure process presents a characteristic of self organized criticality. A method which use self-organized extent parameter α to express stress transfer among units and stress concentration in local units is put forward. Based on the theory that the failure strength of rock units obey second power Weibull distribution, a mechanical model is established with renormalization group theory, and the critical probability of rock failure, pc, was derived. Results indicate that the failure of units is independent and stochastic, and the system evolves to a stable state when the failure probability of unit, p, is less than the critical failure probability pc. When p is higher than pc, the failure of units focus on the macroscopic transfixion tension split plane, which is a dynamic attractor of self organized criticality. The critical failure probability pc and the unit capacity of bearing external load F is related to initial condition. pc as well as F/F0, decreasing with the increase of self organized extent parameter α, and furthermore, F/F0<1. The failure stress of units decreases due to stress transfer.关键词：Self-organized Criticality;far away from equilibrium;critical failure probability;stress transfer
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发布时间：2023-11-28 -
Analysis of Hydrodynamic Coefficients of the Submerged Floating Tunnel Subjected to Homogeneous Flow
摘要：Abstract:For exploration of section shape and aspect ratio influencing on hydrodynamic parameters of submerged floating tunnel tubes, flow fields around submerged floating tunnel tubes with eight type cross sections were simulated using renormalization group k-ε turbulence model with ADINA program. The changing rules of lift coefficient and drag coefficient of the submerged floating tunnel tubes were analyzed. It was shown that curvature of tube surface was one important parameter affecting flow field. Lift coefficients and drag coefficients can be reduced obviously with the reduction of aspect ratio and the application of more flat curvature sections. The changes of pressure become more complicated on the square and rectangular sections which were disadvantage to the stability of submerged floating tunnel structure. Lift coefficient and drag coefficient can be reduced obviously with the design of polygonal section and curved section in the condition of the same area.关键词：submerged floating tunnel;homogeneous flow;lift coefficient;drag coefficient;numerical simulation- 3068
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发布时间：2023-11-28 - 摘要：Abstract:Using industrial titanyl sulfate solution as Ti source, the precursor of mesoporous TiO2 was synthesized via supra-molecular self-assembly route under composite templates (CTAB/P123), which induced hydrolysis and condensation of titanium. Mesoporous TiO2 was obtained after template removal by ozone oxidation, multiple extraction and multi-step calcinations. The samples were characterized by XRD, particle size distribution, N2 absorption and desorption method and FT-IR. The precursor, intermediate and product were all anatase mesostructure, with high specific surface area and hexagonal arrangement. The total titania content and crystallization were increased going with template removal, and mesoporous TiO2 had a narrow pore size distribution, with SBET of 281.5m2/g, average pore diameter of 3.23nm. Catalysis performance of mesoporous TiO2 was strengthened by specific surface area increase, anatase crystal improvement and small amount of SO42- absorption and bonding. And results showed TiO2 samples with high activity on photocatalytic oxidation of methylene blue and esterification for ethyl acetate.关键词：mesoporous titania;industrial titanyl sulfate;composite templates;photocatalsis;esterification
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发布时间：2023-11-28 - 摘要：Abstract:The digestion kinetics of low-grade phosphate ores in intital operation has been investigated under the non-steady state, where concentration of phosphoric acid is variable. A new model equation is presented according to the concentration variation of phosphoric acid in the bulk liquid phase. The kinetics behavior of the digestion process was studied in the ranges 323K～358K.The obtained results show that rate constant of reaction and the weight fraction of phosphate ores conversion increase with reaction temperature rising. The activation energy has been calculated to be 71.86KJ/mol while the pre-exponential factor is 6.521×106. Comparing with experimental data and theoretical calculating value, it indicates that the model fits the experimental data perfectly. The conclusion may provide theoretical base for optimizing process conditions and devising reactors.关键词：low-grade phosphate ores;digestion;kinetics
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发布时间：2023-11-28 - 摘要：Abstract:The performance of two Anammox upflow biofilm filters (UBF) was investigated using synthetic wastewater. Results showed that the Anammox UBFs became unstable under high nitrogen loading rate. Performance deterioration was observed when the nitrogen loading rate exceeded the maximum removal capacity of the reactors. Effluent pH was increased to 8.50~9.05 because of Anammox reaction, which were higher than the optimum pH range of Anammox bacteria, i.e. 6.70~8.30, resulting in direct inhibition of Anammox bacteria and subsequent destabilization of the two Anammox UBFs. Unfortunately, deficiency of free nitrous acid [only (1.9±4.3)×10-5-(2.2±2.5)×10-5 mg•L-1] and excess of free ammonia (as high as 178.1 mg•L-1), both of which were the substrates of Aanammox bacteria, were induced by high pH, resulting in starvation effect of free nitrous acid and toxicity of free ammonia to Anammox bacteria, strengthening instability of the Anammox UBFs. Moreover, the performance of the bioreactors can not recover automatically. Tap water was used necessarily to rinse the bioreactors to wash out the residues. After that, performance recovery can be reached quickly by applying low nitrogen loading rate.关键词：Anammox;stability;pH;free ammonia;free nitrous acid
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发布时间：2023-11-28 - 摘要：Abstract:Houttuynia cordata Thunb (HCT) is selected to absorb Cadmium from soil polluted by Cadmium seriously. The present study shows HCT’s hyper accumulation to Cadmium in soil, and the important roles microbial play in the process of absorption. The accumulation rate is 2.86% when Cadmium’s content is 5 mg•kg-1 in soil, while 1.63% when Cadmium’s content is 10 mg•kg-1. After 72 days’ growth, the number of bacteria in soil is approximately a quarter of that existed before cultivation, so is the number of mildew. But the number of actinomyces increases numerously just when Cadmium was added, and then back to the former level. On the combined effect of HCT and rhizospheric microbes, soil micro-ecosystem could maintain stability well. But a further research of interaction mechanism among HCT’s rhizosphere, actinomyces and Cadmium, is needed. The technology of combined remediation of plant and microbial on heavy metal contaminated soil could really achieve from the perspective of ecological restoration of soil, will have a great prospect.关键词：Houttuynia cordata Thunb;cadmium;phytoremediation;baccumulation;Actinomycosis
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发布时间：2023-11-28 - 摘要：Abstract:The spatio-temporal variation of non-point source pollutants in Lake Wuli has been studied through analysing production process of non-point source pollutants. The results show that: (1) the concentration of pollutants reached a peak immediately for the continuous rainfall, and then reduced gradually along with the time. At the begin of rainfall limiting factor for pollutant concentration in runoff water is splash erosion force, while it changed to pollution amount on underlying surface during the mid-late period. (2)The curve of the pollutant concentration seemed serrate for the intermittent rainfall because this kind of rainfall generally last for a long time, during which there are accumulated new pollutant in some drainage basins. (3)The monthly variation curve of pollutants concentration seemed serrate, influenced by accumulation and attenuation of the pollutants, former rainfall, and the intensity of the rainfall, et al. (4) The spatial variation of pollutants was influenced by the characteristics of the ground, sources of Pollutant, pollutant degree, et al.关键词：Wuli Lake;non-point source;spatio-temporal variation
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发布时间：2023-11-28 - 摘要：Abstract:A two-step method was used to prepare poly L-lactide(PLLA)/ β-calcium metaphosphate (β-CMP) fracture fixation composites. The mechanical strength of these composites is tested and the factors which will affect the mechanical strength were analyzed. The experimental results showed that the bending strength and Young’s modulus of composites prepared by the two-step method were much better than those prepared by the two-step method, reached a maximum of 126.33 MPa and 4.36 GPa, which are close to those of the cortical bone and can meet the request of internal fixation for human bone fractures.关键词：poly-L-lactide (PLLA);β-Calcium metaphosphate (β-CMP);fracture fixation;two-step method
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发布时间：2023-11-28 - 摘要：Abstract:Disubstitued thiophene intermediate and monomer were synthesized by the nucleophilic substitution and transetherification reactions. Poly(3,4-dioctyloxythiophene), a soluble conjugated polymer, was synthesized by electrochemical oxidation polymerization. Characterizations of the intermediate, monomer and polymer were performed by 1H-NMR spectroscopy, fourier transform infrared spectroscopy, and gel permeation chromatography. The process of the electrochemical polymerization, electrochemical redox behaviors and electrochromis of the polymer were investigated by the cyclic voltammetry, potentiostatic method and spectroelectrochemical measurement. The polymer film showed stable redox properties, and its redox potentials were between 580mV and 960mV. It was found to exhibit electrochromic behaviors, and switched electrochemically between clear violet reduced and light blue oxidized states. The triplet peaks were observed between 450nm and 650nm in the UV-vis spectra of this polymer, and the maximum contrast transmittance at 600nm was 18.1%.
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发布时间：2023-11-28 - 摘要：Abstract:Nitrogen is the main impurity in nature and synthetic diamond. In order to synthesize the diamond with the same order nitrogen concentration of nature diamond, diamonds with high concentration nitrogen were synthesized using NaN3 added pure α-Fe catalyst and graphite in cubic anvil high pressure apparatus. The nitrogen concentration in diamond was measured by FTIR fitted with a Hyperion 3000 microscope. The concentrations of nitrogen in diamonds increase with the increase of the concentration of NaN3 and are up to approximate 2200 μg/g of single substitutional nitrogen. However, to date, it was reported that the highest concentration in diamond synthesized with conventional metal solvent catalysts by HPHT was 800 μg/g. The nitrogen concentration of synthetic diamond increase with the increase of NaN3 content when the content of NaN3 are small than 0.7％.关键词：pure α-Fe catalyst;nitride;nitrogen;diamond
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发布时间：2023-11-28 -
Dielectric Properties of 0.68 Pb(Mg1/3Nb2/3)O3-0.32 PbTiO3 Ceramics with Lithium Salt Sintering Aids
摘要：Abstract:Relaxor ferroelectric 0.68 Pb(Mg1/3Nb2/3)O３-0.32 PbTiO３ ［PMN-PT］ ceramics with lithium salts (Li2CO３，LiNO３，LiF) sintering aids were prepared by the columbite precursor method. The phase composition of the ceramic samples was investigated by X ray diffraction (XRD), and the dielectric properties of these ceramics were measured. The results showed that pure perovskite phase is obtained for all the specimens. The dielectric loss decreases and other dielectric properties have not distinctly changed for the PMN-PT ceramics with Li2CO３ or LiNO３ addition, but the dielectric loss increases, the peak of dielectric constants is broaden, the dielectric relaxor characteristic is obvious and the Curie temperature descends for the PMN-PT ceramics with LiF addition. Moreover, the peak of dielectric constants and dielectric loss for polarized PMN-PT ceramics with lithium salts sintering aids shows double peaks. The first peak is the transition between rhombohedra ferroelectric phase and tetragonal ferroelectric phase, which is about 80 ℃; and the second peak is the transition between tetragonal ferroelectric phase and paraelectric phase, which is about 130 ℃ for the sample with LiF addition and about 150 ℃ for the others. However, the sample with Li2CO３ or LiNO３ addition may only have cationic (Li＋) substitution at B site of PMNT with oxygen vacancies formation, but the sample with LiF addition may have anionic (F-) substitution with lead vacancies formation, which may be compensated with oxygen vacancies formed by cationic (Li＋) substitution.- 2270
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发布时间：2023-11-28 - 摘要：Abstract:A new Bi-based (Bi0.5Na0.5)TiO3-based lead-free piezoelectric ceramics with perovskite structure, (1-x-y)BNT–xBKT– yBiFeO3, was prepared by a conventional ceramic sintering technique. The relation between composition and dielectric properties and the relation between composition and frequency were investigated. It was found that the dielectric constant and dielectric loss of unpoled samples is higher that those of poled samples. The dielectric properties of unpoled samples varied insignificant with the increase content of BiFeO3 and those of poled samples increased with the increase content of BiFeO3. The dielectric constant and dielectric loss of unpoled and poled samples increased with the increase content of BKT. The dielectric constant decreased and dielectric loss increased with increasing frequency, and the increase and decrease trend became slowly with increasing frequency.关键词：sodium bismuth titanate;dielectric properties;perovskites structure;ferroelectrics
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发布时间：2023-11-28 - 摘要：Abstract:In this work， poly acrylic acid humidity-controlling composite material was modified by Polyvinyl alcohol，Attapulgite and CaCl2， and then kinetic experiments of moisture absorption/release on the modified and unmodified humidity-controlling composite materials were carried out with the help of batch adsorption/desorption experiment. The thermal decomposition temperature and structure of humidity-controlling composite material were estimated separately by means of TG-DTA and FTIR， and the effects of modification on the moisture absorption/release of humidity-controlling composite material were discussed. Results showed that: （1）The composite of Organic Humidity Controlling Materials, inorganic melt and inorganic mineral was a better way to prepare high effective humidity-controlling material;(2)Compared with the unmodified humidity-controlling composite material， the moisture content and the hygroscopic rate of the humidity-controlling composite material modified by CaCl2 was respectively two and six times of that of the unmodified humidity-controlling composite material at RH<80%; (3) The moisture release rates of the humidity-controlling composite material modified by CaCl2 increased， and all humidity-controlling composite materials were not decomposed when the temperature is below 350℃.关键词：humidity-controlling material, moisture absorption/release properties,absorption of water vapour,poly acrylic acid,composite material
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发布时间：2023-11-28 - 摘要：Abstract:Traditional Gene Expression Programming (GEP) can not discover all optimum solutions for specific multimodal function. To solve this problem, the niche technology was applied to GEP. The limitation of the existing optimization for multimodal function based on GEP was analyzed. A modification strategy with niche radius named AMNR (Adaptive Modification with Niche Radius) and an algorithm named NGEP-MFO (Multimodal Function Optimization based on Niche GEP) were proposed. The application domain of traditional GEP was extended. Experiments showed that compared with traditional GEP, NGEP-MFO can improve the successful ration and accuracy greatly when identifying all optimum solutions.关键词：Gene Expression Programming (GEP);Niche;Multimodal Function Optimization;multiobjective optimization
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发布时间：2023-11-28 - 摘要：Abstract:Current GEP research lacks theoretical foundation. This baffles the developing of GEP. To remedy this issue, this study, defined schema and relative concepts over GEP, analyzed the mechanisms for operators in GEP via probability method, gave proof for the schema theorem over GEP, validated theoretical results by extensive experiments and demonstrates the practical application of schema theorem over GEP. The schema theorem proposed in this paper provides quantitative standard for GEP algorithm’s improving.关键词：gene expression programming;GEP schema;schema theorem for GEP
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发布时间：2023-11-28 - 摘要：Abstract:Existing deep web information extraction methods focused on extracting the templates of well structured pages. But many deep web pages are ill structured.To handle ill structured pages, a new method was proposed.First, the concept of pseudo attributes and their semantic match were proposed.To extract the records’ information is to acquire the semantic match of the records’ pseudo attributes. Then, the records’ pseudo attributes model and their matching algorithm were proposed.Finally, the record’s wrapper model and generation algorithm were proposed. Experiment results showed that the wrapper can achieve a precision of 93% and recall of 91% for ill structured deep web pages.关键词：deep web;information extraction;pseudo attributes;semantic match
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发布时间：2023-11-28 - 摘要：Abstract:Traditional noise removal arithmetic required that the signal-noise-ratio of the image is high, noise removed image by the traditional noise removal arithmetic loss large amounts of edge and texture information in the image. This paper presents a novel procedure for the low signal-noise-ratio (SNR) image noise removal on the local edge-preserving function which makes up the limitation of the traditional methods. Firstly, adaptive median filter is used to remove the part of salt-and-pepper noise and to preserve the edge and texture information in the image. Secondly, local edge-preserving function is built on basic of analyzing the relation of pixels in the local image block. Lastly, a minimization problem is solved by the Poly-Ribière-Polak (PRP) method in order to remove the Gaussian noise and the remnant salt-and-pepper noise in the image. Comparing the results of removing noise, noise removal efficient by our method is better. Especially when the PSNR of the image is 5.4db, the PSNR of the result image is 24.3db.关键词：Noise Removal, low SNR image, local edge-preserving function, PRP method
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发布时间：2023-11-28 - 摘要：Abstract:Accurate object subtraction is a fundamental step of video surveillance and synthesis vision applications. However, segmentation with intensity information alone is prone to fail for objects with diffuse edges, in clutter, or under occlusion. In this work, a novel segmentation method is presented for object with deformation in monocular videos. First, we formulate shape prior term as a distance of deformation by explicitly estimating integral motion of the whole contour, which can then be incorporated with spatial-temporal image information under Markov random field energies framework to be minimized by the Graph Cut algorithm. Then we proposed the concept of dynamic shape to characterize the highly variable nonlinear shape priors. The deformation is represented in an orthogonal basis learned by principal component analysis from training sets and the latent variables are expressed as autoregressive model. Simultaneously, both the orthogonal basis decomposition and the autoregressive model parameters are updated on-line to capture model evolutions. Finally, Promising experimental results demonstrate the potentials of the proposed segmentation framework with respect to noise, clutter, and partial occlusions.关键词：Video surveillance, object segmentation, dynamic shape model, Graph cut
- 3407
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- 816
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- 0
发布时间：2023-11-28 - 摘要：Abstract:Some immune optimization algorithms inspired by the biological immune system, for example the clonal selection theory, the immune network algorithm have been presented, but these algorithms are lack of fast convergence speed, high robustness and are difficult for attaining the optimal solution of optimization problems. The complement system, which represents a chief component of innate immunity, not only participates in inflammation but also acts to enhance the adaptive immune response. In order to improve the capability of immune system resolving optimization problems, a novel immune algorithm based on the complement activation theory-an immune complement optimization algorithm (ICOA) was presented. In ICOA, two complement operators: cleave operator and bind operator are presented firstly, cleave operator cleaved a complement individual into two sub-individuals, while bind operator binded two complement individuals together to form a big complement individual. Then,the convergence, robustness of ICOA were analyzed theoretically,which proved that ICOA could converge to the optimal solution and had high robustness.Finally, the experiments results of ICOA compared with the standard clonal selection algorithm (CSA) showed that the optimal solution,convergence rate, robustness of ICOA were better than of CSA.关键词：artificial immune system;complement activation theory;optimization;complement operator;convergence
- 2592
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- 326
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- 1
发布时间：2023-11-28 - 摘要：Abstract:In order to improve the scalability of GSI which is restricted by PKI’s certification mechanism, a grid security architecture named IBGSI(ID-based GSI) was proposed in which PKI signature scheme was substituted by HIBC signature scheme. Furthermore, TLS handshake protocol was improved to fit for HIBC scheme. At last, IBGSI’s protocol architecture was defined by designing a set of entity interaction operation sequences. In this paper, hierarchical identity architecture, authentication architecture and protocol architecture were researched on about IBGSI. The result showed that IBGSI have advantages of lightweight and efficiency of IBC and advantages of security service of GSI, as well as easy to deploy.
- 2969
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- 488
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- 1
发布时间：2023-11-28 - 摘要：Abstract:In mobile communication systems, users in good channel state were allocated excessive resources by most of scheduling algorithms when dealing with real-time traffics, while users in bad channel state got relatively few scheduling chances. In order to guarantee the delay requirements of real-time traffics and achieve fairness among different users, a packet scheduling algorithm for real-time traffics was proposed in orthogonal frequency division multiple access (OFDMA) systems. In scheduling processes, the expired data packet discarding strategy was adopted to save system resources. Users in good channel state were scheduled in larger intervals, and cumulative packets were sent in one scheduling interval using high order modulation and coding schemes (MCS). Thus users in bad channel state were given more chances to be scheduled. Simulation results showed that the proposed algorithm could meet delay requirements for real-time traffics, and had a better performance in enhancing fairness among users than modified-largest weighted delay first (M-LWDF) and proportional fair (PF) algorithms.关键词：Orthogonal frequency division multiple access;Real-time traffics;quality of service;Packet scheduling
- 2732
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- 830
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- 0
发布时间：2023-11-28 - 摘要：Abstract:In decentralized wireless sensor networks,the final estimation fusion was accomplished in limited bandwidth channel network,in which each sensor often transmitted a few bits to the fusion center because of various constrains.In order to design a scheme to quantify the observation and to get the fusion estimation from the received bits,the estimation fusion problem was changed into that of decision fusion.The interval was divided into subintervals,each subinterval was assigned a hypothesis,suitable cost coefficients of each hypothesis was selected to form the Bayes cost functional,and a mapping from estimation fusion to decision fusion was constructed.The results of simulation proved the theoretical analysis.关键词：decentralized sensor networks;sensor compress rule;fusion rule;estimation fusion;decision fusion
- 2829
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- 508
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- 1
发布时间：2023-11-28 - 摘要：Abstract:Not simply to import data from non-secret computer to the secret computer through universal removable storage devices, but also to prevent classified information in the secret computer leaking through the universal removable storage devices, a data secure import system based on the technology of data diode was designed. The system's hardware and software design were presented, in which the data diode technology to the data import for removable storage device were innovatively applied. The implementation method based on dual fiber transceiver was shown, the impact on the data import reliability was analyzed, and several methods which can improve the reliability of the data import were proposed, such as "slicing-resending", "slicing-writing disk", etc. The design and methods can effectively enhance the system’s reliability and are important reference for the realization of secure import system.关键词：removable storage device;secure import;data diode
- 2559
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- 474
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- 1
发布时间：2023-11-28 - 摘要：Abstract: To improve the chaotic characteristics of Lü system, a new four-dimensional continuous autonomous chaotic system, which can display a novel 4-scroll robust chaotic attractor, is established by adding a linear state feedback controller. By numerical simulating with phase portrait, Lyapunov exponent spectrum, bifurcation diagram and Poincaré mapping, this paper verifies that new system is chaotic in a wider control parameter range and robust with a positive and almost unchanged maximum Lyapunov exponent. This system can evolve from 4-scroll to 2-scroll chaotic attractor as the variation of control parameter. By adding a simple linear integration circuit to a chaotic Lü system, the new chaotic system is implemented by an experimental circuit. It is demonstrated that the experimental observations are remarkable consistent with the results given by numerical simulations.
- 2887
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- 690
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- 3
发布时间：2023-11-28 -
RESEARCH ON METHOD FOR COMPUTER AIDED ASSEMBLY OF MODULAR FIXTURE BASED ON RECONFIGURATION PRINCIPLE
摘要：Abstract:This paper developed a CAD system of modular fixture based on reconfigurable core components by lead reconfigurability theory into modular fixture assembly because of the analysis that modular fixture are reconfigured by different core components. This system makes some fixed and parameterized structure, which can fulfill certain functions as core components, and constructed modular fixture components library. Introduce a store method for typical path and a workflow of the construct design module. The application this system has proved that it can finish the task of modular fixture assembly well.关键词：modular fixture, reconfigurability, assembly ,core component- 2749
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- 334
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- 1
发布时间：2023-11-28 - 摘要：Abstract:Time, quality, cost and service are the key factors that affect the competitive power of modern manufacturing. Therefore, it is necessary to design a reasonable and high efficient optimal disposition tactic of manufacturing resource to respond user’s manufacturing resource requirement. In this system, UML was used to classify and model manufacturing resource, WSDL was used to description and encapsulation manufacturing resource. The model and tactic based on Secondary fuzzy comprehensive evaluation was presented to optimal allocate manufacturing resource. Finally, an example was used to describe the whole course of resource optimal allocation. The results show that the system can search the optimal resource node which meet the evaluating indicator of time, quality, cost and servece in user’s manufacturing task.关键词：Manufacturing grid;Manufacturing resource node;Resource optimal allocation;Secondary fuzzy comprehensive evaluation
- 2475
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- 336
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- 3
发布时间：2023-11-28 - 摘要：Abstract: In order to improve the reliability and safety of the Electric Power-Steering System (EPS) system, this paper adopts the integrity robust fault- tolerant control strategy on the design of the feedback controller for EPS System . Based on the Lyapunov stability theory and Lyapunov functions, the paper firstly researches the rule of robust fault- tolerant control which has function integrity for the sensor failure in the linear continuous system which also has some degree of the uncertainty of parameter fluctuation. this paper gives the sufficient -and- necessary conditions for the system itself robustly be stabilized and its design method and steps are given. Then, by applying such integrity robust fault- tolerant controller for the EPS system ,the data simulation results shows that the EPS close-loop system not only has not sensitive for the sensor failure ,which means that EPS system can stably work under some sensor failure condition, but also has robust stability for limited parameter uncertainty.关键词：fault-tolerant control;robustness;integrity;sensor failure;Electric Power-Steering System
- 3313
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- 1376
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- 0
发布时间：2023-11-28
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