最新刊期
卷 38 ， 期 1 ， 2006
- 摘要：Abstract:On the basis of the field data of water temperature, a new formula for estimating water temperature of river by using meteorological factors is put forward by using the method of least squares. The new formula can be used to estimate the water temperature of river where there is no water temperature monitoring data, and can provide the scientific foundation for environmental impact assessment of river basin development.关键词：water temperature;air temperature;humidity;wind speed
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发布时间：2023-11-28 - 摘要：Abstract:Basin eco-environmental quality evaluation is an important adjust and control measure for coordinating pressure, state and response factors of basin eco-environmental system, and achieving basin sustainable development.The difficulty is how to determine weights of evaluation indexes with reason, and how to effectively deal with fuzziness and randomness existing in the evaluation process. For this reason, a fuzzy pattern recognition model based on maximum information entropy principle and genetic algorithm was proposed, which formed a new model, named EFPR EQEB for short. The applied result of Chaohu basin shows that as a method for basin eco-environmental quality evaluation with distinct concept of mathematics and physics, EFPR-EQEB is concise and general. Its computation result is objective and reasonable, so it can be widely applied in different resources and environment comprehension evaluation.关键词：basin eco-environmental quality evaluation;fuzzy pattern recognition;maximum information entropy principle;Genetic algorithm;Chaohu basin
- 1952
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- 46
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- 9
发布时间：2023-11-28 - 摘要：Abstract:In order to investigate the nonlinear deformation of aluminum bending members, the influencing factor analysis of loaddeflection relationship was presented adopting finiteelement analysis (FEA) methods. The loaddeflection curves of 126 aluminum bending members were calculated considering structural dimensions, material properties and load distribution. The theoretical formula of loaddeflection curves was deduced from the momentcurvature relationship proposed in EC 9, some loaddeflection curves were evaluated by numerical integrating. The differences between the results of FEA method and of theoretical method were discussed. The coefficients of the theoretical formula were modified by FEA results using nonlinear fitting method. The semiempirical formula for computing the loaddeflection curve of aluminum bending members was then proposed. The result shows that the influence of nonlinear material properties of aluminum alloy should be considered when computing the deformation of aluminum bending members, and the calculating methods of this paper are comparatively accurate.关键词：aluminum bending members;load-deflection relationship;finite-element analysis;theoretical calculation;non-linear fitting
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发布时间：2023-11-28 - 摘要：Abstract:The hydraulic inverse problems can be applied in many fields such as comprehensive ecological improvement, groundwater resources protection, hydraulic engineering, ocean engineering etc. This paper broaden the concept of the inverse problems from synthesizing, controlling, classification and connect inputting, recognizing the system parameter to parameter control, source control, boundary control, initial control and shape control. In the solution of inverse problem, the paper advances some new theories such as pulse-spectrum method, discreticise-optimization method, perturbation method and modern controlling method etc. Based on these new methods, a series detailed steps to setting different problems are listed.关键词：inverse problems;hydraulic;pulse-spectrum method;discreticise-optimization method;controlling metho
- 1828
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- 28
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发布时间：2023-11-28 - 摘要：Abstract:In order to strengthen flood risk management in a river basin, to upgrade the capability of flood control, and to reduce the losses of lives and properties in urban areas, a numerical simulation model was proposed in this study on the basis of 2D shallow water equations. A satisfactory result has been obtained by applying it into the Fuji River basin in the central Japan. Results indicate that the numerical simulation model proposed can be adopted not only in risk management of a river basin, but also in the study of real time operations of rescue jobs and evacuation routes in a municipal region suffering from a serious flooding event.关键词：shallow water equations;flood;inundated area;inundated waterdepth
- 1718
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- 2
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发布时间：2023-11-28 - 摘要：Abstract:Some formulas now insue cannot correctly predict sediment transport rate at Yichang Station of Yangtze River. This paper statistically analyzed 246 sets of the observed data from 1959 to 1964 and 1973 to 1974 at Yichang station,and regarded sand bed load as uniform sand.Based on the analysis of the forces acting on the grain particle and sediment rolling incipient model,the calculation formula for incipient velocity of sand bed-load was established.The coefficient K in the formula varies with the discharge and follows the exponential distribution.In the meantime, the formulas of sand bed-load transport rate were established.The formulas were verified by the observed data of Yichang station in 1975.Calculated values according to the formulas were in good agreement with the observed data.关键词：Yichang station;sand bed-load;incipient velocity;sediment transport rate
- 1685
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- 28
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发布时间：2023-11-28 - 摘要：Abstract:In order to scientifically allocate replaced water from east-route and mid-route of the South to North Water Transfer Project, which is allocated initially to downstream regions of yellow river,and again to the upstream and midstream areas, based on analysis on TOPSIS,this paper pointed out the problem that short distance may be coinstantaneous between the scheme to ideal solution and that to opposite ideal solution. “Vertical distance” is proposed to replace Euclid distance, at the same time, TOPSIS model is improved and applied. Through calculating distance between allocation water indexes of upstream and midstream areas of yellow river and ideal solution, the percentage and the amount of allocation water can be gained. The outcome can be used to provide decision basis with allocation water proposed in the paper.And the study result is important to mitigate inconsistency between supply and demand in yellow river watershed.关键词：TOPSIS;replaced water;allocation;standard deviation
- 1953
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- 24
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发布时间：2023-11-28 - 摘要：Abstract:In the geomechanical model test where the temperature analogous material is applied, mechanical parameters and thermal physical properties are changed by changing temperature. And it's influence degree will determine the reliability of the test result. In this paper model test and numerical analysis are used to study the temperature characteristics of the material. The analysis shows that the influence degree of the test displacement made by the change of thermal physical property is 6%, and the influence degree of stress is -6%～9%. The adaptation of temperature range is less than 75 ℃.关键词：geomechanical model test;temperature analogous material;thermal physical property
- 1703
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- 6
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发布时间：2023-11-28 - 摘要：Abstract:To prevent cavitation damage of hydraulic structures with high speed flows，forced aeration device is commonly adopted as an economical and effective engineering technique. During engineering protecting of the side walls with high speed flows and low pressure areas tend to be neglected. In paper based on theoretic study and model experiment，preventing cavitation damage of the dragon raise head spillway tunnel side walls was studied，an aerator with a sudden widen（ie. lateral deflector）and a vertical drop was put forward to bottom of anti-arc. This type aerator eliminates un-airflow area in the side-walls. The air entrainment quantity is obviously affected by lateral deflector. The lateral air chamber is an important aeration mechanism when the lateral air chamber is connected to the bottom cavity，which prevent cavitation damage of sidewalls and soleplates effectively.关键词：High head;Dragon-Rraise-Head free flow spillway tunnel;Protecting side-walls cavition damage by aeration
- 1805
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- 26
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发布时间：2023-11-28 - 摘要：Abstract:It is the purpose of this paper to design a high-performance locking-free low-order plate element, based on the Hellinger-Reissner variational principle of Mindlin-Reissner plates. By means of the energy optimization condition，we present a 7-parameter bending moment field, and assume that the equilibrium equations associating bending moments with shear forces are satisfied strictly within the elements. With the aid of a reduced interpolation operator, we obtain an accurate locking free quadrilateral hybrid element. The numerical experiments reveal that the proposed plate element possesses good properties despite distorted meshes, and is free of shear locking in the case of very thin plates.关键词：Mindlin-Reissner plates;Mixed/hybrid methods;locking free;energy optimization
- 1531
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发布时间：2023-11-28 - 摘要：Abstract:A new method for the determination of boron by low pressure strong acid cation-exchange exclusion chromatography and the conductivity detector was proposed. The chromatographic column was filled with strong acid cation-exchange resin with improved granularity and degree of sulfonic, and mannitol-nitric acid-water was used as eluent. The method needn't a suppressor column, and the chromatographic conditions of separation and detection were modified. The detection limit was 5.0×10-5 mol/L, and the linear range was 0.2×10-3～5.0×10-3 mol/L for boron, with RSD=2.0%(n=11). The method was applied to the determination of boron in industrial waste water with satisfactory results.关键词：low pressure ion chromatography;boron;retention behavior;industrial waste water
- 1675
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发布时间：2023-11-28 - 摘要：Abstract:Degradation regularity of Linear Alkylbenzene Sulfonates（LAS） was studied in the reaction stage during the treatment wastewater from synthetic detergent production by SBR process, and the primary analysis of bio-degradation kinetics of LAS was reported.The results showed that after aerating for about 6 hours, the concentration of LAS in the wastewater can reach national effluent standard under such experimental conditions(initial concentration of LAS ≤ 90 mg/L；temperature range:（23.0±0.5）?℃). Bio-degradation process of LAS can be simulated well by both Monod model and the first order reaction equation under the condition of low substrate concentration. The corresponding kinetic parameters were determined.关键词：SBR;synthetic detergent;linear alkylbenzene sulfonates;kinetics
- 1918
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- 2
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发布时间：2023-11-28 - 摘要：Abstract:An ethanol sensor was developed useing polymer membrane and optical fiber technology．The sensitive membrane for the optical fiber ethanol sensor was prepared from polyvinylidene fluoride(PVDF) under optimized conditions．The performance of the PVDF membrane optical fiber sensor was investigated by determining the concentration of ethanol．The optical fiber ethanol sensor was linear in a wide range of ethanol concentration of 0～60% (v/v) and had a fast response time(T＜ 30 s)．The relative standard deviation for 50% ethanol was 0.3% (n=6)and the lifetime exceeded six month. Signals were steady and not easily interfered．The sensor was used to determine the ethanol content in wine specimen and the results were consistent with those by gas chromatography and pycnometer methods．
- 1471
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发布时间：2023-11-28 - 摘要：Abstract:Artificial Neural Network (ANN) was used to build a predictive model of the combined effects of independent variables (pH, temperature, hydrolysis time, enzyme/substrate ratio and the concentration of substrate) for antioxidant peptides production. Optimum operating conditions for the maximum antioxidant capability were reported as: 1)the hydrolysate which could scavenge the radical DPPH· most effectively were hydrolyzed for 4.8h with Alcalase at pH?7.5 and 60?℃, muscle∶water=1∶1.9, enzyme/substrate =0.2%; 2)the hydrolysate which could scavenge the radical OH· most effectively were hydrolyzed for 6?h with Alcalase at pH?7.5 and 60?℃，muscle∶water=1∶1.4, enzyme/substrate =0.16%; 3)the hydrolysate which could scavenge the radical O2·- most effectively were hydrolysis for 4.3?h at pH?7.5 and 60?℃, muscle∶water=1∶1, enzyme/substrate =0.2%. The results showed that ANN is very helpful tool for the bioactive peptides production.关键词：ANN;optimization;bighead carp;radical scavenging capability
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发布时间：2023-11-28 - 摘要：Abstract:Using the characteristics of the genetic algorithm and the immune algorithm, an immune-genetic algorithm was presented for solving TSP (traveling salesman problem) more effectively. The energy function and adjusting mechanism of antibody concentration were introduced into this algorithm .The mathematical formulas of antibody ,antigen ,antibody concentration and energy function for solving TSP were established. The procedure of solving TSP was described. The experimental results showed that this algorithm procure has the shorter route and faster convergence than the other algorithms for the same TSP, including traditional artifical neural network ,genetic algorithm and simplex immune algorithm.关键词：immune-genetic;energy function;antibody concentration;TSP
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发布时间：2023-11-28 - 摘要：Abstract:A novel reduction method of high dimensions based on artificial neural network was proposed for the effect reduction of Chinese traditional medicine prescription. Based on the similarity information between properties, it created a property distance matrix.The matrix was loaded into an artificial neural network, and through training the artificial neural network, it got the reduce result of high dimensions. Based on the new method, a prescription analyze system of Chinese traditional medicine was implemented. The efficiency of the new method was proved by experiments in effect reduction of Chinese traditional medicine.关键词：ANN;high dimensions reduction;similarity;prescription effect;vector;similarity distance
- 2039
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- 18
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- 14
发布时间：2023-11-28 - 摘要：Abstract:In order to improve the precision and increase the speed of Chinese personal name recognition, a new model based on artificial immune system for Chinese personal name recognition was proposed.The concepts of “self", “non self", “antibody" and “antigen" were defined. The mechanisms of immune learning, immune recognition and immune memory were built.The correlative algorithm was presented. The results showed that the novel method is more effective in some aspects than the traditional ones based on statistics, corpus, and decision tree. Thus, it provides a good solution to the field of text mining.关键词：artificial immune;text mining;name recognition
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发布时间：2023-11-28 - 摘要：Abstract:By analyzing the degree of freedom for the cut graphs and the split graphs,a sufficient and necessary condition for split graphs completion was presented.A lower limit of the number of elements in the set of primitives for minimal cut graphs in 2D and 3D was proposed,which is a lower limit of connectivity of structurally well-constraint graphs.关键词：geometric constraint solving;connectivity;cut graph;split graph;decomposition
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发布时间：2023-11-28 - 摘要：Abstract:Embedded systems are composed of hardware and software. Many functions of the systems can be realized by either software or hardware. In order to partition the system according to function and performance requirements, such as cost, size, power consumption and timing, a hardware/software co-synthesis for SoC design was proposed, the corresponding mathematical model was presented, hardware/software co-synthesis was translated into optimal paths of directed graphs, and the feasible solutions were got in the whole solution space by conditional traversal. This method, which evaluates many performance factors and works in reuse of IP cores and software components, worked automatically and overcame the deficiency of the traditional methods. Finally, an example of the sender of audio and video subsystem of a PDA platform illustrated the practicability and effectiveness of the approach.关键词：SoC;co-synthesis;partition;IP core;software component
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发布时间：2023-11-28 - 摘要：Abstract:To formulate a model that can evaluate the effectiveness of information system safety measurements,the relativity between safety measures counting certain risks (1∶n or m∶1) was studied.Supposing that the effectiveness of different safety measures has abstract function relation,the function was extended into power series by normalization, introduced all possible mathematical relativity,and eliminated redundant relativity by F-statistic and Gram-Schmidt orthography algorithm.By regression analysis,we get the high precision evaluation model than the line evalution model.关键词：safety measures;composition independency;composition complementary;composition repellency;F-statistic;Gram-Schmidt orthography algorithm
- 1822
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- 9
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发布时间：2023-11-28 - 摘要：Abstract:The advantages and latent defects of Ao-Chen-Bai and Yuan Ding’s group signature schemes were analyzed respectively,and defaults were found in Yuan Ding’s scheme and then an improved group signature scheme was developed in accordance with the formal definition of group signature. While reserving the advantages of those currently existing schemes,this scheme is capable of resisting forgery attack,and thus can be used to build more security systems.关键词：group signature;discrete logarithm;forgery attack;unlinkability
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- 20
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发布时间：2023-11-28 - 摘要：Abstract:To increase antibody generating speed in artificial immune system, a chaos negative selection algorithm was presented which is based on the chaotic character of immune system. Over spread character of chaos sequence was used to generate candidate set of detector firstly, and then the chaos disturbance was used to get some individuals directly and reduce search space, additionally chaos initial value sensitivity was used to overcome redundancies. The experimental results showed that the algorithm noy only retains the diversity of population but also increases the generating efficiency of detector.关键词：chaos;negative selection;artificial immune;detector
- 1900
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- 12
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发布时间：2023-11-28 - 摘要：Abstract:The net-grid type analog fractance circuit for 1/2 order fractional calculus was put forward and analyzed.The equivalent conversion between T type,Π type,T type primary fractance circuit and 1/2 order net-grid type analog primary fractance circuit,the equivalent conversion between syntony crystalloid,cross-linked variable transformer and 1/2 order net-grid type analog primary fractance circuit,and the frequency characteristic of 1/2 order net grid type analog fractance circuit were disserted.Any fractional order bionic neural-type pulse oscillator was generated with analog fractance circuit.The results of computer simulation showed that the fractional order bionic neural-type pulse wave accurately simulates actual biology neural-type pulse wave’s shape characteristic by and large.关键词：fractional calculus;syntony crystalloid;fractional order neural-type pulse oscillator;hysteretic neural-type pulse oscillator;electro-neurogram
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发布时间：2023-11-28 - 摘要：Abstract:Doubletalk detection (DTD) is used to sense whether the far-end speech is corrupted by the near-end speech in echo cancellation. In order to improve the performance of doubletalk detection, the output of an adaptive acoustic echo canceller (AEC), instead of a far end speech, and the output of a microphone were employed to form detection statistics. By taking advantage of the strong correlativity between the output of the AEC and the output of the microphone when the near-end speech is absent, the detection performance was improved and the computational complexity was decreased. Simulation results showed that better performance of this algorithm compared with the performance of other cross-correlation based algorithms can be achieved.关键词：doubletalk detection(DTD);cross-correlation;acoustic echo cancellation(AEC);adaptive filter
- 2406
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- 36
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发布时间：2023-11-28 - 摘要：Abstract:The biodegradable polyetheresteramide-based polyurethane (PEEA-U) copolymers were prepared by melt polycondensation method from ε-caprolactone, 6-aminocaproic acid, poly(ethylene glycol), and toluene diisocyanate (TDI). The polymers were characterized by1H-NMR, FTIR, and the thermal properties were studied by DSC and TGA/DTG analysis. With the addition of TDI, the melting temperature and the enthalpy increased . The hydrolytic degradation behavior of these copolymers were also studied.The results showed that with the decrease of the pH from 9.10 to 4.02, the degradation rate increases rapidly, and the degradation rate of the PEEA-U-E is slower than that of PEEA-U-0, which might be due to the difference in the macromolecular weight and the crystallinity of the copolymers.关键词：biodegradable;polyetheresteramide copolymer;polyurethane
- 1446
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- 2
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- 1
发布时间：2023-11-28 - 摘要：Abstract:The influence of deforming aging on the structure and property of Fe17Mn5Si8Cr5Ni0.5NbC alloy was studied using SEM and TEM. The result showed that, after deforming Fe17Mn5Si8Cr5Ni0.5NbC by 10%, it produces a great amount of γ/ε interface and stacking fault which improves the intensity of matrix and suppresses the occurrence of the plastic deformation of cannot athwart. When the fault partially reserved, it provides more nuclei for stress induced ε martensite, and the shape memory effect and recovery stress of the alloy were improved. The deformed shape recovery ratio of aging promotes much more 22％～40％ than the undeformed aging, and also the greatest recovery stress promotes to around 35％～143％ when heating, and recovery stress of room temperature promotes to around 10％～38％.关键词：deforming aging;carbide;shape memory alloy;shape recovery ratio;recovery stress
- 2147
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- 2
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- 2
发布时间：2023-11-28 - 摘要：Abstract:The monodispersed cross linked GMA-DVB particles were prepared by dispersion polymerization using PVPK as stabilizer, water/alcohol mixture as reaction medium and BPO as initiator. The influence of different ratio of water/alcohol, the proporition of the monomer and medium, the concentration of the initiation and the effect of mix speed on the micropheres' shape, yield, diameter and its distribution was investigated. Polymerization process was tracked and observed by microscope to summarize and grope the polymerization mechanism of dispersion polymerization. The monodispersed cross linked GMA-DVB particles have the diameter of 3～5?μm.关键词：dispersion polymerization;monodisperse;polymer microspheres;polymerization mechanism
- 1676
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- 4
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发布时间：2023-11-28 - 摘要：Abstract:In order to supply laser-light-source which owns the trait of high stabilization of frequency beat-wave interferomete mechanism of thermal frequency stabilizing of double-longitudinal mode was studied. Based on the mechanism, the length of laser tube was controlled by controlling the discharging electrical current of laser as mainly controlling way and using advanced faradic way as little controlling way, which is a original creation. The fuzzy PID controller was designed to stabilize laser frequency based on the fuzzy controlling theories and expert systems, which doesn't need to found the mode of researched objects. The fuzzy PID controller has a quit adaptive ability for time lag, non-linearity and timeliness. The experiment results of the frequency stabilizing system demonstrated that the precision of frequency stabilizing has little change, but the time of advance heating is obviously shortened and the ability of anti-jamming obviously strengthened. Even if a strong jam acts on the system, it also can soon come back after getting ride of the jam.关键词：thermal frequency stabilization;fuzzy control;PID controller;double-wavelength laser
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发布时间：2023-11-28
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