Abstract:By analyzing the advantages and disadvantages of commonly used calculation methods and introducing a nonlinear pile-soil interaction model, a method for calculating the internal forces of cantilever piles was proposed, which can consider the pile-soil interaction. Firstly, finite bar elements were used to discretize the pile structures, and then, elemental stiffness matrixes were calculated and incorporated into global stiffness matrix. Secondly, the nonlinear function relationship between earth pressure and pile displacement in or out of the foundation pit was assumed, and then the nonlinear function array of joint loads was established. Thirdly, the overall stiffness equation was formed according to the global stiffness matrix and nodal load function array, and was solved to obtain the nodal displacement array by using the Newton-Raphson method. Finally, the internal forces of pile and lateral earth pressure were calculated with the elemental stiffness equations and nodal displacement array. The example analysis shows that the proposed method is simple and convenient, fully reflecting the characteristics of nonlinear variation of earth pressure acting on piles, and revealing the mechanism of pile-soil interaction well. Therefore, it is suitable for the internal force calculation of cantilever piles.

Abstract:An experiment of debris flow was carried out to study the influence of grain size distribution on starting progress mode by using the self-developed small-scale model flume under the condition of artificial rainfall. By using coarse sand (1~2 mm) and fine sand (0.075~0.25 mm), the model was made according to the quality ratio. Model test study finds that, with fine content increasing from 20% to 100%，failure pattern changes from layered and clumpy slide to fluidized flow. By using GeoDog software to analyze displacement and a pore pressure gauge to measure pore pressure changes, we have found sliding plane developing in layered and clumpy slide, and pore pressure decreasing with crack generation, and increasing with water seeping into crack. There is no crack development in fluidized flow, and pore pressure momentarily drops to a small value when damage occurs. The average volume of the starting for fluidized flow is bigger than that for layered and clumpy slide. The formation mechanism for layered and clumpy slide is that water penetrates quickly, causing slope foot damage, and the slope collapses for losing support. For fluidized flow, the permeability coefficient is small, the soil of the back is highly saturated, and liquid causes the slope to decline rapidly. Based on the indoor model test of rainfall-induced debris flow, the formation mechanisms of debris flow modes were summarized.

Abstract:To investigate the seismic behavior of RC frames with energy conservation masonry infill walls, two RC frame models with two-floor single span, one with infill walls and the other without infill walls (bare frame), were tested with the pseudo-static experiment. The cracking distribution of frame with infill walls was described, and the load-displacement hysteretic curves, skeleton curves, rigidity degradation and strength degradation were discussed in comparison with the bare frame. The results show that the lateral load-bearing capacity and structural lateral stiffness of the RC frame, but not the ductility, can be increased by infilling walls in the frame.Due to the presence of the infill walls, the rigidity degradation and strength degradation of the frames will be sped up. However, there is still enough stiffness when the RC frame with infill walls is destroyed, which indicates the good resistance to collapse resistance of the frame with energy conservation masonry infill wall.

Abstract:In response to the problem of rigid link of anchorage point, which occurs to spatial cable fixed on the girder and the tower of cable-stayed bridge, on the basis of tangent stiffness matrix of nonlinear spatial truss element by differential method, and according to the characteristics of the forced rigid arm without deformation but rigid motion, the relationships between the total amount and increment of the displacement and the end force of ends of rigid arms in global coordinate system were presented by treating rigid arm as the spatial vector and employing its finite rotation formula and differential method. Then, the explicit expressions of nonlinear tangent stiffness matrix of spatial stay cable 3-D truss element with rigid arms on both ends were obtained. A finite element program based on the algorithm was developed to analyze the geometric nonlinear behaviors of cable-stayed bridge. Three examples, including spatial trussed structure with or without rigid arms and a cable-stayed bridge in construction process, were employed to perform spatial geometrical nonlinear analysis. The results show that the new algorithm can solve the rigid link of anchorage point completely, and it provides a powerful tool for refined geometrical nonlinear analysis of cable-stayed bridge.

Abstract:In order to increase the structural longitudinal stiffness and facilitate the swing method, the side girders of trough section of the cable-stayed bridge on the Kunming-Shanghai passenger line were inserted into the pylon so as to form the pier-tower-girder fixed region. For the (32+80+112) m single tower cable-stayed bridge, the structure and force of the fixed region are very complicated. The large general-purpose finite element software ANSYS was used to establish the pier-tower-girder fixed region model to study the stress distribution of the fixed region. The correctness of this model was verified. Based on this region model, the force transmission and stress distribution of the fixed region were investigated, and the effect of the local structural details on the fixed region stress was studied. The analysis results show that the global stress level of the fixed region is lower than the girder and tower, but there are stress concentration phenomena in the fixed region, such as the intersection point between the floor of the trough girder and upper tower, and the corner of the human tunnel in the fixed region. The degree of the stress concentration was relieved significantly by improving the structural details.

Abstract:The forecast of the current urban road travel time is mostly limited to single-source data and the prediction accuracy is not high. Based on the floating car GPS data and microwave detector traffic data, a model of travel time was built in the fusion method. Wavelet neural network was optimized by using genetic algorithms, which can solve the blindness and the randomness of selecting wavelet neural network initial parameter, thus greatly improving Web search efficiency and the speed of training. The predicted travel time is in good agreement with video observed data. The results show that the model is effective and reliable.

Abstract:The extension & compaction scanning algorithm based on LTI (Linear Travel-time Interpolation) ray tracing algorithm can properly trace the ray path of the direct wave, diffraction wave and echo's, but it has the following problems: low computational efficiency and slow convergence speed. Aiming at these problems and using the cross-scan mode to improve the algorithm, an improved extension & compaction scanning algorithm based on the cross-scan mode was presented. Theoretical analysis and the results of numerical calculation show that the improved algorithm not only maintains all the advantages of the extension & compaction scanning algorithm, but also has a higher computational efficiency. When the model is mesh more refined，the advantage of the improved algorithm is more significant in computational efficiency.

Abstract:The purpose of this paper was to study the vegetation cover and water level change functions of East Dongting Lake wetland. The vegetation cover corresponding to water level change was also investigated. After the preliminary treatment of TIMESAT, the normalized difference vegetation index (NDVI) time series was adopted to analyze the relationship between vegetation cover and water level in the divided zones (A, B, and C). Then, NDVI sample autocorrelation curve was used to show the differences of the three areas under study. Lastly, the spearman correlation coefficient (ρs) of NDVI time series corresponding to water level was used to discuss the effects of the Three Gorges Dam. The results indicated that, (1) all the NDVI time series under the impacts of water level formed an annual cyclical change style. Every cycle had two crests, one in April and the other in October. In the flood period, the curve formed a trough in July. Quadratic polynomial fitting showed that the critical water level of maximum vegetation cover was about 24 25m. (2) The degree of the effects of water level on vegetation cover was Zone A

Abstract:Hexachlorobenzene's (HCB's) estrogenicity change and potential mechanisms when mixing with a typical natural estrogen, 17-Estradiol (E2), were investigated. Human breast cancer cell MCF-7 increase examination was used. The results showed that HCB had very strong estrogenicity, but the mixture of HCB and E2 showed strong rivalry effect, i.e., E2 and HCB greatly weakened each other on endocrine disrupting effect. Mechanism analyses showed that E2 and HCB could interfere with the endocrine system via the endocrine receptor channel and the MAPK signal channel. The rivalry effect between E2 and HCB was unrelated with the traditional endocrine receptor channel, but depended strongly on the non-traditional ERK channel. E2 decreased the HCB activation of ERK protein, and decreased the expression of p-ERK protein, thus interrupting the transcription of MAPK signal. The transcription factor analyses showed that E2 weakened the function of HCB mainly by decreasing the expression of c-Myc protein.

Abstract:The yaw system of the megawatt-class wind turbine produced severe vibration in the process of work. A virtual prototype model of the yaw system was established in ADAMS based on the active yaw theory of the megawatt-class wind turbine. Vibration analysis results have shown that the first order natural frequency of torsional vibration of the yaw system is 17.6947Hz, the second order natural frequency is 55.8166Hz, the third order natural frequency is 85.1 412 Hz, and the fourth order natural frequency is 170.1823Hz. Dynamic analysis results have shown that the nacelle has to bear severe oscillation at the end of the yaw, the amplitude is as high as 0.15rad, and it will last 20s. The vibration of the yaw system can be reduced by adding a feedback control to the frame of the megawatt-class wind turbine.

Abstract:An improved operating strategy of genetic operator sorting genetic algorithm (GA) was used for the multi-objective optimization of crane's lifting path planning in three-dimensional space. First, space path planning of multiple degrees of freedom was transformed into that of planar path points planning by constructing mathematical models of crane's lifting scene and pose space. Second, the optimization targets, including the shortest lifting path, best security, minimum of movement changes, were determined. Then, suitable direction and step size of the insert operator and mutation operator were selected with the addition of a memory operator for multi-objective optimization. Experiments have demonstrated that this algorithm can take several factors into account and generate multiple paths to select at one time.

Abstract:Theoretical and experimental studies were carried out on a new type of self-compensating bi-conic hydrostatic bearing. The structure and operating principle of self-compensating bi-conic hydrostatic bearing was introduced. Theoretical models of the lubrication film were built with perturbation method, and the influence of rotor motion on the restrictor gap was taken into account for the self-compensation restricting equation. The model was solved in finite element method (FEM) and was validated with experiments. Load carrying capacity, fluid flow rate, stiffness and damping coefficients were studied. The results have shown that the self-compensating hydrostatic bearing has higher radial load carrying capacity than fixed-slot compensating bearing under the same condition，and it has high stiffness coefficients when used under low load.

Abstract:Wind tunnel test of a 7 500t floating crane was conducted with a 1∶200 scaling model. The balance force was measured to discuss structure response against different working conditions and wind inlet angle. 78 working conditions were considered according to 3 typical luffing angles, 2 possible wind field landscapes and 13 wind inlet angles. The test results were concluded to non-dimensional results. The results indicate that: 1) wind load along isometric direction (135°wind angle) reaches the highest point; 2) The smaller the luffing angle, the larger the wind load; 3) The wind field landscape plays a small role in wind response.

Abstract:To address the slow dynamic response, large overshoot and long stability time of yaw rate of a steer-by-wire vehicle in an emergency steering by the ideal steering ratio control, this paper proposed a yaw rate feedback control method on the basis of driver steering intention recognition. The proposed method focuses on normal steering and emergency steering. The vehicle was controlled according to the ideal steering ratio control in normal steering. And it was controlled according to the yaw rate feedback control superimposed on ideal steering ratio control in emergency steering. The method adopts driver steering intention recognition to determine in superimposing yaw rate feedback control. The driver steering intention recognition was modeled and implemented by using multi-dimensional Gauss Hidden Markov Model, offline parameter training and online recognition. The results have indicated that the driver steering intention recognition model has good precision and the method can effectively improve the transient steering response of the steer-by-wire vehicle.

Abstract:The coil copper resistance of the large-power rectifier transformer used in the metal smelting, chemical and electrolytic industries increases as the temperature increases, and so does the corresponding basic copper loss. The cooling system of the transformer ensures that the rectifier transformer runs under specified operation conditions of temperature rise. In addition, it reduces the windings' consumption by lowering the temperature. However, the application of cooling system will consume a sum of energy as well. It depends on whether the whole system reaches energetic minimum. This paper made a careful study on the relationship between the power dissipation of the rectifier transformer, the power consumption of the cooling system and temperature according to the operating data of an aluminum company. The research reveals the optimal temperature rise and cooling power for the minimum energy loss of the rectifier transformer, which paves a way for realizing the rectifier transformer's comprehensive energy saving.

Abstract:With the development of clean energy in the electric power system，wind power has been utilized in large scale , but its characteristics will deeply affect the stability of the power system. This paper compared the wind turbine structure of the doubly-fed induction generator (DFIG) and direct drive synchronous generator (DDSG), and analyzed their reduced order model. Wind power turbines were added to the system of two regional systems. The systems had good damping properties, but the systems' damping model was changed significantly. When wind power generator capacity increased in the system, doubly-fed induction generator could weaken the new local oscillation mode damping. Direct drive synchronous generator could enhance the region associated with a local oscillation damping.

Abstract:The composite insulator surface hydrophobicity detection is one of the primary means to determine its anti flashover performance. This paper introduces the sparse representation classification algorithm to classify composite insulator's hydrophobic image. It uses the smallest normal method to calculate the coefficient of sparse representation and searches the training sample image that best matches the test image by calculating the minimum residual image, therefore the test image's hydrophobic HC level is accurately identified. The algorithm has successfully avoided complicated feature extraction in general pattern recognition algorithms, thus providing a new way for composite insulator's hydrophobic image recognition and detection. The experimental results show that the method can be effectively applied in the composite insulator's hydrophobic image classification.

Abstract:A real-time on-line automatic debugging and measuring system for microcomputer compensated crystal oscillator (MCXO) was designed. The system integrates the S&A4220 temperature test chamber, a high precision frequency counter, a personal computer, and a special microcontroller based on C8051F061 with 8 measuring channels. The control program on PC was designed by means of Labview. All main technical parameters of MCXO can be measured automatically with this system. Within the temperature range (-40 ℃ to +85 ℃), the frequency-temperature stability of developed MCXO is ≤±7×10 -8 .

Abstract:Manganese sulfate solution with high iron content was obtained by leaching a kind of low-grade pyrolusite from Hunan Province with pyrites and concentrated sulfuric acid, or, in the two-ore-acid-leaching method. The methods of iron deep-removing from the manganese sulfate solution were studied. Various iron-removing methods were compared, such as neutralizing hydrolysis method, partial hydrolysis of goethite method, and ammonium jarosite process method, ammonium jarosite-goethite union method. The results showed that ammonium jarosite-goethite union method was most suitable for the removal of iron from the solution. The iron removal rate reached 99.96% at 90 ℃ in a 1 hour reaction. Meanwhile, the manganese loss rate was lower, the slag volume was smaller and the filtration was easier. The deep-removing of iron has laid a foundation for the preparation of high purified manganese sulfate solution.

Abstract:The synthesis of zinc porphyrins tailed by 4,4'-biphenyldiol and their spectral property studies were reported. The results showed that the maximum fluorescence emission wavelength of these zinc porphyrins tailed by 4,4'-biphenyldiol was about 650 nm, which was located in the visible light region, and was satisfied with the optical properties of the ideal photodynamictherapy drugs. The zinc porphyrins tailed by 4,4'-biphenyldiol will become an excellent photosensitizer.

Abstract:Based on the linear and geometric-plane features of linear programming, a special matrix was defined together with a transferring operation. A directionally iterating and transferring model of simplex's basis-vertex was given. With the help of this model, a two-step Vertex Steepest Extreme Direction Transition iteration algorithm for linear programming problem was proposed. In addition, by this simplex locally regularized method, the degenerated vertexes' iteration transition can be changed into the non-degenerate vertexes' iteration transition, thus eliminating the negative effect of vertex degeneration on vertex iteration transition processes.