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Base on the design of seepage control, the three-dimensional non-steady saturated - unsaturated seepage finite element analysis program CNPM3D is used to establish the three-dimentional finite element seepage model of junction area during operating period. The seepage field of dam site area is studied under the different anti-seepage curtain arrangement scheme. Specifically, the seepage gradient and the seepage discharge of the panel, major material zone, foundation curtains and two sides abutment curtains are analyzed to evaluate the stability of the major district of dam area, in order to provide suggestions for choosing the seepage control standard in the next deepen design stage.The calculation results show that the panel and the impervious curtain anti-seepage effect is remarkable.Impervious curtain can greatly reduce the total seepage flow of the dam and its foundation.However the curtain deepened to 1Lu has little effect on seepage discharge. It is showed that the seepage prevention standards of 3 lu should be proposed in the deepen design stage for both security and economic benefit. The achievement and experience of this seepage prevention design should be taken into consideration for other similar projects.

The main dam of Banqiao reservoir consists of the concrete overflow dam and the earth dam in both sides, which are connected by concrete lateral key wall. Field observation shows that serious leakage problems exist at the connection of the overflow dam and the earth dam in right bank. According to the real size of structures, the FEM model are established to calculate and analysis the seepage field characteristics at the connection part. The potential ground water level shows that the reservoir water flowing to the downstream bypassing and passing through the lateral key wall and the anti-seepage curtain. And there exists partial seepage passage at the connection part. As the contact seepage gradient along the lateral key wall is uneven, the contact leakage at the connection part is not fully safe although the average contact seepage gradient is within the permissible range. Effective measures should be taken to solve the seepage defects at the connection part.

Two weak acid resins (WT-1, WT-2) with different pore structures were prepared through suspension polymerization from methyl acrylate (MA) and divinylbenzene (DVB). Cu2+ was employed as the adsorbate and bath experiments were carried out to investigate the adsorption performance of the two resins. The addition of porogen (toluene) enlarged the exchange capacity, specific surface area and average pore diameter of resins, leading to the faster adsorption rate and higher maximum adsorption capacity. The adsorption capacity increased 3.5~28.5% with the rise of porogen/monomer ratio from 0 to 30%. This work shows the porogen influence on the adsorption kinetics and thermodynamics of weak acid resins.

Two methods based on modal decomposition in circular cylinders are presented here. One is based on bi-orthogonality relation and the other is based on boundary discretization for mode matching. The two methods are comprised in numerical implementation and the efficiencies are evaluated.

For the leakage problem caused by geomembrane defect, the unstable saturated-unsaturated seepage theory and Galerkin finite element method have been adopted. So a three-dimensional finite element numerical model of an earth-rock dam with geomembrane anti-seepage system is simulated by the unstable saturated-unsaturated seepage finite element method. The influnence on seepage field for the varying degrees of geomembrane damage is analyzed, and the overall and local seepage field characteristics of the dam for geomembrane defect leakage are discussed. The results show that the numerical method provides an effective way to study the leakage problem of geomembrane defect.

Seepage failure is an important factor in causing dam-break of earth-rock dam, so the study of anti-seepage reinforcement for dilapidated reservoirs is always an important topic to earth-rock dam. Changli reservoir, since the completion, soil flow and failure by piping occur in dam slopes, the safety of downstream residents has been threatened both in life and property. Based on the comparisons of the effects of anti-seepage reinforcement schemes,the result shows that, for this clay dam, concrete cut-off wall can improve the seepage state obviously and has a higher operational stability. Thus, the concrete cut-off wall is designated as the recommended anti-seepage scheme for Changli reservoir.

Using an atmosphere simulation test platform，the performance of a common rail diesel engine when the engine was fueled with diesel fuel (B0) and different blending ratio of biodiesel (B10, B20, B30)．The results show that at the same altitude(81kPa), with the mixing ratio of biodiesel increases，the common rail diesel engine has higher brake specific fuel consumption and lower power，but it has lower smoke．The biodiesel has a litter influence on the brake specific fuel consumption and power of the common rail diesel engine. The power of B30 is reduced by 4.38% in comparison with B0 maximally. The brake specific fuel consumption of B30 is increased by 4.32% in comparison with B0 maximally. The smoke of B30 are reduced by 22.5％, 38.6%, 57.1% in comparison with B0 maximally.

To study the effect of the biodiesel on the performance of the high pressure common rail diesel engine performance, a experiment is conducted about the high pressure common rail diesel engine uses diesel fuel and different blending ratio of biodiesels. The results show that with the rising of the altitude, the engine power and the brake specific fuel consumption reduce, exhaust gas temperature increases; At the same altitude, the engine fueled with different blending ratio of bio-diesel has higher brake specific fuel consumption in comparison with fueled engine, but it has lower power, with the increase in bio-diesel blending ratio, engine power, fuel consumption increase.

In order to digitize the signal of high frequency or ultra-high frequency, clock distribution technology with the same frequency but different phase is utilized as a solution to this difficulty. The principles of high-speed analog-to-digit converter (ADC) by the lower rate ADC module, key technology and key module of the data acquisition systems are studied. From the aspects of system architecture, clock distribution module based on the AD9520, ADC module based on the AD9480 and data processing, the design method of ultra-high-speed ADC by clock distribution mode are explored. The results show that: driving many ADC modules with serial clocks of the same frequency but different phase in parallel to sample the same signal, the sampling frequency of the ADC system is the sum of each ADC sampling frequency. Four AD9480 modules are driven by four-way 250MHz clocks with phase fault 90°, respectively. And 1GHz samples per second can be attained, which is four times of the sampling frequency by monolithic AD9480.

For the echo of the laser signal was relatively weak and accompanied by a lot of noise in a foggy condition, a multi-pulse cumulative method for enhancing weak laser signal was proposed. The enhancement principle and method of multi-pulse signal accumulation was studied, and with it the weak signal was processed. The matched filter algorithm was used to extract the characteristics of laser echo signal, the original signal and the accumulated signal was processed by the matched filter, respectively, which greatly improves the signal to noise ratio (SNR). The experimental results show that: four separate laser signals accumulated together enhance SNR by twice; the accumulation of multi-pulse laser signal can effectively improve SNR, and the matched filter can strengthen the signal while suppressing noise.

with the difficulties of extracting the feature of faint laser signal reflecting from non-cooperative target in foggy conditions, the spatial correlation threshold filtering approach was proposed based on spatial correlation filtering. The thought, theory and implementation methods of the spatial correlation threshold filtering was elaborately studied, especially, the selection of the threshold for the filter was analyzed. A comparative study of threshold filtering, spatial correlation filtering and spatial correlation threshold filtering was carried out to verify the filtering effect for the laser signal reflecting in the foggy environment, the experiment results shows that: spatial correlation threshold filtering method has the most effective filtering. The processing results show that the new method can effectively eliminate noise and keep weak laser signal characteristics, which lays solid foundation for identification of target nature.

Based on the actual conditions of the project and related experience, the seepage model of diversion tunnel and its surrounding rock mass was built to analyze its seepage stability. The seepage field was calculated by using finite element method (FEM) and cut-off negative pressure method. Two typical cross-sections and working conditions were chosen to evaluate the seepage stability of the surrounding rock mass. According to the results, the seepage gradient is larger when one tunnel is filled with water while the other is empty. The maximum seepage gradient is less than the allowable seepage gradient, so the surrounding rock mass of the diversion tunnel can meet the demand of seepage stability.

Sizing of material flaw is addressed in the multipath scene, and a method is developed to detect an isolated sized flaw and estimate its height based on imaging theory of different path profiles. A signal model based on the multipath higher order reflections of the flaw is built to detect the sized flaw. Multipaths are predicted and identified on the basis of the direct reflection path, which is relatively easy to be identified using the conventional flaw detection techniques. Direct reflection path and combined path are applied to detect the flaw from the top, and multipath w is to detect its bottom of the flaw. Ultrasonic imaging is formed and synthesized by all the identified multipaths, which shows the size of the material flaw. Simulations and experimentations demonstrate that the flaw sizing can be calculated utilizing the time-of-arrivals of the multipath signals.

According to the actual engineering conditions of Haokou RCC Gravity Dam, the 3-D FEM model of the typical overflow dam section and its foundation is set up. Using the response spectrum method, the responses of earthquake acceleration, displacement and stress of the dam and their distribution laws were studied under the seismic loading, and the anti-sliding stability of dam is also analyzed. The calculation results show that under the design earthquake condition, the maximum principle stress response of dam body is 2.26MPa, which appears at the dam heel. The safety factor of stability against sliding on the face of the dam foundation is 1.43 and the stability against deep sliding is 3.2. So this dam section can meet the strength and stability requirements of standard, its earthquake-resistant safety could meet the requirements of standard.

Ultrasonic signature of flaw is studied in the multipath scene, and a method is developed to localize the flaw by only single mono/bi-static measurement. A signal model based on the concept of multipath is built to construct flaw position, of which multipath scenarios are reviewed for signature of flaw depth. Multipath scenarios may be identified by direct path, which is relatively easy to be detected. Algebraic solution is proposed to solve the multipath equations to obtain the position of the flaw depth. Experiments show that the solution of the flaw depth is valid.

This paper presents the design methods of CQU-DTU-B21 airfoil for wind turbine. Compared with the traditional method of inverse design, the new method is described directly by a compound objective function to balance several conflicting requirements for design wind turbine airfoils, which based on design theory of airfoil profiles, blade element momentum (BEM) theory and airfoil Self-Noise prediction model. And then an optimization model with the target of maximum power performance on a 2D airfoil and low noise emission of design ranges for angle of attack has been developed for designing CQU-DTU-B21 airfoil. To validate the optimization results, the comparison of the aerodynamics performance by XFOIL and wind tunnels test respectively at Re=3×106 is made between the CQU-DTU-B21 and DU93-W-210 which is widely used in wind turbines.

As one of the key structures of hydropower underground projects, buried high-pressure steel bifurcations have complex structures and undefined force states. Based on practical condition of the buried high-pressure steel bifurcation of Sandaowan Hydropower Station, a nonlinear three-dimensional finite element model with parametric design language is established to analyze the changing law of the stress of the lining affected by the dimension of the strengthened beams. It is proposed that to increase the height of the strengthened beams can be reduce the phenomenon of stress concentration effectively in the bifurcation, which can be served as a theory reference for the engineering design and construction.

The enhancive effects of lactic acid on the antibacterial activities of haw pectic oligosaccharides (HPOS) against the Gram positive bacteria Staphylococcus aureus, Bacillus subtilis and Streptococcus faecalis, were investigated. Both HPOS and lactic acid showed dose and pH dependent antibacterial activity against S. aureus and B. subtilis. S. faecalis was sensitive to the HPOS but was resistant to the lactic acid. The antibacterial activity of HPOS against these three bacteria could be enhanced by co-treatment with lactic acid. The results revealed that HPOS may be useful as a food preservative, and lactic acid was able to enhance the antibacterial activity of HPOS, allowing for a further improvement in its efficiency. This additive effect obtained with lactic acid would likely result in a reduction in the dosage necessary for food preservation.

Purple sweet potato pigment is a natural food pigment, the stability is important to its quality assurance. The effects of metal ions on the stability of purple sweet potato pigment were investigated. The results showed that Mg2+and Fe3+ were conductive to pigments stability in the initial storage, and with the concentration increased, the pigment was more stable. But K+, Ca2+, Na+, Cu2+, Mg2+ and Fe3+ had brought the color density, the color intensity and the preservation rate of purple sweet potato pigment down in the long-term storage.

According to the practical situation, the 3-D finite element model of Sandaowan underground powerhouse caverns on Taolai River is set up for analyzing the behaviors under earthquake action. Based on static stress field of the surrounding rock mass, and with the selection of appropriate seismic waves for dynamic time-history analysis method, the dynamic responses of underground powerhouse caverns are analyzed. It is shown that the time-history waveform of dynamic displacement of given points has a very similar variation regularity with that of acceleration, and the wave phases of both are almost synchronous. The dynamic displacements and principal stresses of the given points on rock walls are with the vibration of low-frequency characteristics, the acceleration response is with the vibration of high-frequency characteristics.

Subsurface drip irrigation (SDI) that has a wide application prospect is one of the high efficiency water-saving irrigation techniques. Research on regulation of soil-water dynamics in irrigation design parameters of SDI has important points in improving its irrigation design and guiding its practical function. In this study, soil wetting patterns were investigated in laboratory experiments which were operated at three different dripper discharges (0.76, 1.15 and 1.25 l h-1) and two different irrigation amounts (4.6 and 9.2 l). The results showed that, (1) with the increase of dripper discharges from 0.76 l h-1 to 1.25 l h-1, water content around the emitter are increasing from 0.225 cm3 cm-3 to 0.300 cm3 cm-3, (2) increasing the dripper discharge and irrigation amount increased the size of the wetted zone, (3) upward distance of the wetting front is less than downward distance and horizontal distance of the wetting front presents symmetry distribution at the same the dripper discharges and irrigation amount, (4) with the increase of irrigation amounts from 4.6 l to 9.2 l, water contents of the vertical and horizontal direction are increasing 10% to 20%.

Rare earth (RE) ternary complexes of Eu0.5Ln0.5(NPPD)3×DPQ (HNPPD = 1-(naphthalen-2-yl)-3-phenylpropane-1, 3-dione; DPQ = Dipyridobenzoquinone; Ln3+= Nd3+, Er3+, Ce3+, Dy3+), Eu1-xYx(NPPD)3×DPQ and Eu1-xLux(NPPD)3×DPQ (x= 0.0, 0.1, 0.3, 0.5, 0.7, 0.9) were synthesized by the reaction of RECl3×6H2O with HNPPD and DPQ in stoichiometry. The UV-vis and fluorescence properties of the complexes were investigated. The experimental results show that the luminescence efficiency of Eu3+complexes was enhanced by doping some other lanthanide ions.

Difficult in soil-water characteristic curve achieved, existence of non-uniqueness and indistinct in influence of unlinear deformation characteristics of soil about density and water content, deformation characteristics of unsaturated soil were studied difficultly with general triaxial test, thus direct application of unlinear Duncan-Chang model in unsaturated soil was restricted. General triaxial tests with combined dry density and water content are carried out, changing rules of parameters of Duncan-Chang model are summarized, mathematical functions between dry density, saturation and parameters of the model are established. Analysis shows that deformation characteristics of unsaturated clay are influenced obviously by saturation and dry density. Among them, the larger the saturation, the higher strain becomes under the condition of the same dry density and main stress difference, and the less the dry density, the higher strain becomes under the condition of the same saturation and main stress difference. Moreover, the main parameters of Duncan-Chang model keep close correction with dry density and saturation, and the both mutual effect can be expressed by multiplication. This shows that mechanical characteristics of unsaturated soil can be studied with general triaxial test, thus it will be used easily in project.

An analytical solution based on modal decomposition is presented to investigate Lamb wave scattering at plate end. Take boundary condition into biorthogonality relation, a matrix equation is established with all matrix elements have analytical expressions. The scattering feature is then expressed in matrix form, named as reflection matrix, which has explicit expression composed of those matrixes. Calculation examples have be implemented when antisymmetric modes are reflected. Scattering coefficients are figured out in a range when frequency-thickness product vary from 0 to 8kHzm, to prove the calculation efficiency. The calculation precision is very close to the least square method based on model discretization.

Multi-Sinks wireless sensor networks, a current research focus, has better stability and effectiveness compared to the traditional single-SINK structure. To solve the problem how to complete the tasks within the possibly shortest time, a task scheduling algorithm(DMTA) based on divisible load theory in multi-Sinks wireless sensor networks is proposed. In DMTA, the tasks are distributed to wireless sensor network based on the processing and communication capacity of each sensor by multiple Sinks respectively. By removing communications interference between each sensor, reduced task completion time and improved network resource utilization achieved. Simulation results show that DMTA reasonably distributes tasks to each node in wireless sensor networks, and effectively reduces the time-consuming of task completion.

Due to the popularity of knowledge discovery and data mining, in practice as well as among academic and corporate professionals, association rule mining is receiving increasing attention. The technology of data mining is applied in analyzing data in databases. This paper puts forward a new method which is suit to design the distributed databases.