Abstract:Flac 2D was used to simulate pile installation and the subsequent consolidation, considering one dimensional consolidation in clay. The parameters selected for Flac code, such as initial effective stress and shear modulus of different stress history before installation, were analyzed. The effective stress and excess pore pressure of different overconsolidation ratio after installation were obtained. After the complete dissipation of excess pore pressure, the effective stress field around pile was generated. The effects of stress history, initial water content, initial shear modulus on undrained shear strength of soil were investigated, and the influence of soil structure on excess pore pressure after installation, and on radial effective stress and undrained shear strength after consolidation was also discussed. The traditional cavity expansion theory takes it as a plane strain assumption, which ignores the three dimensional nature of this problem.

Abstract:The computation of earth pressure against rigid retaining wall usually adopts classical Rankine or Coulomb's theory, which can only get limit state of earth pressure, but in many practical cases, the earth pressure against retaining wall is in the non-limit state. So, this paper presented an analysis of the backfill under the mode of translation based on the improved thin-layer element method and the relationship between friction angle and displacement variation. The distribution of earth pressure, resultant force and its action point of a retaining wall under non- limit state were obtained. The optimal solution of earth pressure was obtained by using PSO (particle swarm optimization) to search the potential slip surface, on which the inclination angle of the segment for the thin layer element was extracted as a valuable. Then, the effects of the internal frictional angle, wall displacement on the distribution of earth pressure, resultant force, action point and potential slip surface were discussed. Finally, the results of the proposed method were compared with laboratory test data, which shows that the calculated results have a good agreement with the experimental observations.

Abstract:On the basis of the mechanism of rock creep, the rock creep process was regarded as the superposition of linear and nonlinear rock creep process according to its phase characteristic. An elastic-plasticity damage cell model, which can describe the nonlinear or accelerated rock creep process, was developed by introducing the damage theory and the law of damage proposed by Kachanov. Connected with Kelvin cell model, which can preferably simulate the linear or the decelerated rock creep process, a rock creep model reflecting the features of the full rock creep process was obtained. The accelerated rock creep process was established and its simple and feasible parameter determination method was put forward. A new technique simulating the full rock creep process was developed, which can simulate the rock deformation process from decelerated to accelerated creep, and its parameters are few and easy to be determined. Finally, it shows that the model or technique proposed is reasonable and feasible after a comparison between the model and the experimental curves.

Abstract:Similarity principle was applied to obtain the certain conditions of strength similarity among reinforced concrete column and beam under axial compression, and compression with large eccentricity. The theoretical values of the reinforcement ratio and the thickness of concrete cover were derived, and by selecting the thickness of concrete cover of the model on the bearing capacity, the influence of similar errors was analyzed. The analysis shows that the same reinforcement ratio with the prototype is appropriate for the model test in the reinforced concrete member model test. For axial compression column, the thickness of the concrete cover of the model does not have any error. For the reinforced concrete beam, the thickness of the concrete cover of the model takes prototype protective layer thickness divided by 0.5 times the proportional coefficient. The error can be controlled within 10%. For large bias column, it is suggested that the thickness of the concrete cover takes prototype protective layer thickness in addition to scale coefficient.

Abstract:Firstly, the super-elastic deformation behavior of shape memory alloy was studied through material test, and its stress-strain curves were equivalent to multi-linear model to obtain its calculation parameters. Then, a new enhanced energy dissipation SMA damper was proposed, with its structure, working principle, design methods, and restoring force model also being introduced and elaborated. Finally, a total of three analytical models were established including a conventional steel frame, a steel frame setting diagonal SMA cables and a steel frame installing new SMA damper. Through the seismic time-history analysis, the seismic performance of these three models was comprehensively investigated. The results show that the hysteresis loop of the new SMA damper is full and the new SMA damper performs perfect energy dissipation capability. Moreover, the proposed SMA damper effectively suppresses structural displacement response and inter-story drift angle response under rare earthquakes.

Abstract:An adaptive control strategy for the CVD sky-hook control strategy of a 7DOF full car was proposed. An algorithm for identifying road unevenness was obtained via the mean square of the suspension travel under variable road input and vehicle speed. And then, all optimal control parameters under different driving conditions were optimized off line by the genetic algorithm. At last , the optimal control parameters were applied on an online control system, which has demonstrated that the adaptive CVD control strategy can improve the ride comfort in “soft” driving mode, handling stability in “sport” driving mode and safety in “safe” driving mode.

Abstract:In order to reveal the cavitation mechanism of diesel injection process, a numerical model has been developed to investigate the cavitation processes in injector nozzle according to the conservation of mass, momentum and the basic rules of the mixture fraction balance. Then, the numerical simulation results of cavitation effect were analyzed. It is discovered that the atomization performance of high pressure injection nozzle becomes poor and the vapor volume fraction and the thickness of cavitation in the injector nozzle decrease, and the radius of the nozzle inlet rounding lip tends to increase. The numerical study also points out that the amplitude of inlet pressure is reduced with the small variations of outlet mass flow, which is better for the accurate control of injection quantity. The nozzle internal cavitation phenomenon is strengthened at elevated fuel temperature and injection pressure conditions. However, increasing the injection pressure is more conducive to enhancement atomization.

Abstract:In view of the disadvantages of traditional double closed-loop vector current control (VCC), such as slow dynamic response, pool decoupling performance and high current harmonic distortion, a transient mathematical model for the VSC-HVDC system in d-q synchronous reference frame was developed. Then, a double integral sliding mode direct power control strategy (DISM-DPC) combining the features of direct power control (DPC) and integral sliding mode control (ISMC) was proposed. Double integral sliding mode decoupling based on the deviations of instantaneous active and reactive power were designed, and the corresponding control laws were derived. Finally, the simulation model of the system was established by PSCAD/EMTDC, and the results show that the method can achieve power decoupling, improve the dynamic and static quality and robustness of the system with simple algorithm, and effectively reduce chattering caused by switching action.

Abstract:The datas of Neural Progenitor Cells chip and Embryonic Stem Cells ChIP-Seq from NCBI were analyzed to explore the function of RFX1. A comprehensive analysis showed that RFX1 binding sites spread across each chromosome. Most of them resided in chromosomes 1, 2, 4, 5, 7, 9 and 11, but the least in chromosome Y. And genome wide localization prediction showed that RFX1 binding sites ubiquitously and generally existed throughout the genome. 53.2% of these sequences were distributed in promoter, 22.5 % in the intergentic, 13.1% in the body, and 11.2% in the enhancer in the mouse genome. In addition, the biological processes of RFX1 target genes were analyzed. The majority of the affected biological processes were mainly cellular and metabolic.

Abstract:Rare-earth-doped zinc oxide nanoparticles have been prepared with three different experimental methods, including precipitation method, alkali corrosion method and template method. The produced samples were analyzed on the upconversion optical properties. The structure analysis was performed on the samples by X-ray diffraction (XRD); the scanning electron microscope (SEM) was used to observe the powder's morphology and to estimate the particle size; the upconversion spectrum of sample was tested by fluorescence spectrometer and then the mechanism analysis was carried out. The results show that, the optical properties of nanoparticles are related to the size of particles. It has been proved that the smaller hollow spheres have better optical performance than that of the larger solid spheres. For hollow spheres, it is in favor of red upconversion when the size is smaller. On the contrary, it is in favor of green upconversion.

Abstract:In order to address distortion caused by cooling speed for aluminum profile in water spray quenching processing, a finite element model for cooling process in water spray of the extruded aluminum profile was developed on the basis of the FLUENT and ANSYSWORKBENCH software platform. The temperature field, the residual stress and the strain of cross section in quenching processing were analyzed under three runs with different water spray speeds. After process parameters were optimizated, the results showed that the nozzle size speed of the section profiles in different parts was more reasonable, and the distribution of temperature and equivalent stress was more uniform. It presented the smallest equivalent stress and strain of cross section. Finite element analysis can help improve nozzle distribution and spray velocity in the quenching process of the aluminum profile, which can provide guidance for practical production in industry.

Abstract:An adaptive chaotic hill-climbing particle swarm optimization was presented in order to overcome the unability to find all extreme points, local optimum and slow convergence speed at later time caused by Particle Swarm Optimization (PSO) in multimodal function optimization. An improved PSO was proposed , and the population of diversity was measured by entropy. A dynamic chaos mechanism was used to increase the diversity when there is a lack of population diversity, and a hill-climbing method was introduced to improve the convergence speed of PSO in later period. Four kinds of typical multimodal functions were chosen to test the performance of the improved algorithm in solving complex multimodal function optimization problems. The results show that the improved algorithm has better performance than the existing algorithms.

Abstract:Sentence semantic similarity algorithms based on HowNet ignored the fact that different words have different contribution weight to sentence similarity value, and therefore, the similarity result is not quite reasonable. In order to solve this problem, we proposed an improved algorithm based on word frequency. The algorithm calculates the similarity between words based on HowNet, both considering the distance and the height of primitives. Then, a frequency function of words in corpus as a weight factor is embedded into the sentence semantic similarity algorithm, which reduces the proportion value that the high frequency words devote to sentence similarity calculation. The sentence semantic similarity experiment results show that the improved algorithm is much better in rationality as well as in matching with people's subjective judgment.

Abstract:The problem of city garbage disposal was investigated under an environment of polymorphic uncertainty. In some settings, a class of management of solid garbage disposal was formulated as an interval fuzzy optimization model. Possibility degree operator for the order of interval numbers was firstly defined in axiomatic method, and for given weight coefficients and confidence levels, a deterministic equivalent formulation for the original model was obtained on the basis of such a definition. Then the problem was solved in the ordinary linear programming method. The model and the solution method were applied into a practical management problem, and the results indicate that the model and the solution method are effective.

Abstract:Because of the multiple characteristics of t-blocking sets in finite projective spaces，we can not get the precise value in a general t-blocking set．There is a famous Ball theorem dealing with the lower bound of the t-blocking set．This article has improved the conditions and conclusion of Ball theorem and we have obtained a new lower bound of t-blocking set in the PG(2,q)．

Abstract:To address the problem of modelling under the condition of random parameters using Probit quantile regression, this paper proposed Bayesian Probit quantile regression model based on the Metropolis-Hastings algorithm. According to the Probit quantile structure, the M-H algorithm was ulitized to simulate the posterior marginal distribution by choosing the prior distribution of the parameters. The model posterior distribution in the different quantile points was obtained by using Monte Carlo simulation, and at the same time, Probit quantile regression, smoothed Probit quantiel regression and Bayesian probit quantile regression method were used to estimate the parameters of the model and to compare the differences from the estimation of parameters, respectively. The research shows that Bayesina Probit quantile regression comprehensively describes the influencing factors of discrete variables, and the estimation of parameters is more accurate and efficient.

Abstract:Based on the data from household survey in Hunan, Fujian, and Jiangxi, this paper applied contingent valuation method (CVM) to analyze the WTP of policy forest insurance. By using 364 valid questionnaires, the paper estimated the farmers' WTP for policy forest insurance. They are 3.61 yuan/acre in Hunan, 2.18 yuan/ acre in Fujian, and 1 yuan/acre in Jiangxi. Then, the paper analyzed factors which influence farmers' WTP by using Cox proportional hazard model, and concluded that, when the family size is bigger, the soil yield is lower and the forest area is bigger, attention to policy forest insurance is more, and then, farmers' WTP for policy forest insurance will be higher. Besides, Men' WTP for policy forest insurance is higher than women. Finally, the following suggestions are given: first, strengthening the publicity of policy forest insurance, second, improving policy forest insurance system based on local conditions, improving insurance companies' service levels and enhancing the management of policy forest insurance market and finally, promoting the establishment of rural financial system.