Abstract:A modeled recycled concrete is proposed.According to the meso and microlevel mechanics parameters and constitutive relationships of the fivephase medium materials of recycled concrete,the failure mechanism of recycled concrete is numerically simulated.An investigation is made into the replacement of recycled coarse aggregate,the strength of the new or old hardened cement paste,the thickness of the old hardened cement paste,and the strength of interfacial transition zone (ITZ) on the mechanical properties of modeled recycled concrete under uniaxial compression.The results indicate that the strength of the new and old hardened cement paste have a remarkable influence on the initial elastic modulus and peak stress.The thickness of the old cement paste has some certain influence on the initial elastic modulus and peak strain.Furthermore,the influence of the strength of interfacial transition zones on the initial elastic modulus,peak stress and peak strain is not distinctive.

Abstract:The constitutive equation of postbuckling column is derived based on large deformation postulation to describe point contact and line contact respectively.The deformation of column can be regarded as the combined deformations of different typical small columns.The angle of rotation of the middle point in typical column is introduced in the constitutive equations of different typical columns.The results show that the constitutive equations in different contact state obey the same formulation,and the contact state depends on the value of new introduced variable.

Abstract:Aiming at the rodlike polypropylene fiber introduced from Japan and common steel fiber used in the shotcrete lining,this paper presents a study on changes of the shear strength of concrete with different matrix strength and fiber content through the shear test of 72 specimens divided into 18 groups.The results show that as the fibre content increases,the shear strength of the rodlike polypropylene fiber concrete increases at first and then drops down,while the shear strength of the steel fiber concrete increases.When the fibre content is within 0.5%,the shear strength increase of the rodlike polypropylene fiber concrete is close to that of the steel fiber concrete,when the fibre content exceeds 0.5%,the shear strength increase of the rodlike polypropylene fiber concrete is lower than that of the steel fiber concrete.The fibers improve more on the shear strength of the C30 concrete than the C50 concrete.Finally,fitting formulas on the shear strength of the fiber concrete are gained based on the theory of regression analysis,and the calculation results of the formulas are accordant with the experimental results well.

Abstract:Based on the flexural differential equation of elastic piles,a simplified analytical solution of an axially loaded single pile subjected to lateral soil movement is put forward.In this solution,the subsoil is simulated with the Winkler’s spring model and a twostage method proposed by Poulos is introduced to establish the equations.The flexural differential equation is solved by the finite difference method,which is more convenient and more adaptable for layered foundations.The method is validated by some typical examples calculated by other methods.Results show that the interactive effects between soil movement and the axial load have some influence on the behavior of piles by generating additional displacements and bending moments which may be quite different according to the properties of both piles and soil as well as boundary conditions of pile head.The boundary conditions of pile head have obvious influence on the distribution of displacement and stress of pile.An effective restrain at the head of pile can reduce the negative couple effects of axial load and lateral soil movement acting on the pile.The present method can be applied to practical engineering.

Abstract:The lateral displacement function of the gravity retaining wall was normalized through several excavations in Shanghai.The simplified formula of lateral deformation of gravity retaining wall was deduced through principle of minimum potential energy.Meanwhile,factors that affect deformation of gravity retaining wall were also analyzed.The simplified formula was adopted to calculate the lateral displacements of gravity retaining walls of ten excavations.The average relative error between the calculated results and the measured results is 13.5%,which proves that the method is suitable for calculating lateral displacement of gravity retaining wall.

Abstract:The structure of pores in the concretion of cement bentonite slurry is measured by mercuryinjection method,and the permeability coefficient of the concretion is measured by permeability test.According to the test results,the connections between the permeability and pore structure as well as the dosage of cenment and bentonite in the cement bentonite slurry are analyzed.The analysis reveals that the permeability of cementbentonite slurry concretion is controlled mainly by critical size of pores in the concretion.The smaller the critical size of pores,the stronger the permeability resistance of the concretion is,and other pore structure parameters have little influence on the permeability of the concretion.With the increase of the dosage of cement and bentonite,the critical pore size of the concretion will gradually decrease,and the dosage of cement has greater influence on the critical size of pores than that of bentonite.

Abstract:The experimental analysis of single pile jacked in layered ground is conducted to study the behavior of compaction effect during the pile pressing process.Through comparison and analysis of displacement field of different uniform soft and hard ground during pile penetration,the different displacement modes of soil located on different positions are obtained.Moreover,the tests reveal the soil displacement behavior produced by different positioning and the depth of the pile,especially at layered soil interfaces.The experimental results show that a lag effect existed between the maximum displacement and the pressed pile depth in the uniform ground.And,the maximum radial and vertical displacements appear at the soil interface,due to the difference of soft and hard soil mechanical properties,the changing laws of displacement show mainly that the soft soil become larger,the hand soil become smaller.The experimental results allow for a better understanding of the inherent mechanism of compaction of the jacked pile during the penetration process.These results are important for estimating the influence of pile installation and guiding pile design during construction projects.

Abstract:The relationship between conflicting traffic streams at road intersection is essentially a game,thus game theory is applicable in analysis of standards for setting traffic signal lights at road intersection.The competitions between auto streams,and that between auto stream and pedestrian stream were modeled respectively as twoparty symmetrical and twoparty asymmetrical chicken games.Mixed strategies Nash equilibrium for the chicken games were deducted and proved to be lower in social efficiency than that of pure strategy Nash equilibrium,signifying the necessity for introduction of traffic signal lights.Replicator dynamics in rationally bounded evolutionary game was applied to deducing the evolutional stable strategies (ESS) for the chicken games.The ESS analysis proved reasonableness of the mixed strategies of the games.The accident rates and their corresponding annual accident numbers from the games may be used as standards for setting traffic signal lights.A case study was conducted on standards for setting traffic signal lights in Shanghai.Finally,practical significance of parameters change of the chicken games was investigated.

Abstract:Simulation method was used for realtime estimation of performance indices at signalized intersection.The dynamic iterative relationship among vehicle delay,stops,and queues at intersection and signal status was modeled based on simulation step.Characteristics of traffic flow on link were simulated by cell transmission model (CTM) while those of evolution at intersection described by micro traffic state.Delay incurred by straightforward vehicle flow on an approach of a signalized intersection was researched.Results show that variance among several classical delay models will increase as degree of saturation increases.Analyses show that estimation result based on simulation step is basically in the range of variance among the classical delay models.For one intersection,time complexity of the iterative algorithm is O(n).

Abstract:A methodology for setting up a realtime traffic control microsimulation and calibrating the microsimulation model at signalized intersection was proposed. The optimum values for calibration parameters were obtained by minimizing the error between the simulated and field platoon dispersion graphs. The methodology was applied to the intersection of Caoan Road and North Jiasong Road in Jiading District of Shanghai by using particle swarm optimization (PSO). Experimental results show that this methodology can work out a valid solution by only 11 iterations which can make its error less than 2%. The methodology proves to be effective and efficient and also provides a basis for testing or developing traffic control models at signalized intersection.

Abstract:To improve efficiency and benefit for loadingtransportation system,a decisionmaking model for single vehicle loadingtransportation,under comprehensive consideration of the restraints of goods weight and volume as well as loading capacity of vehicle and timewindow,is developed.Based on an analysis of the adaptability for genetic algorithm application to the model as well as its possible problems or defects,technologies such as decimal coding and maximum preserved crossover operator as well as adaptive crossover mutation are adopted to inherit good properties of parents and improve the phenomenon of algorithm premature and stagnation as well as enhance its optimization performance.Constraint test subroutine for distribution weight,volume and delivery time window embedded in genetic algorithm in order to reduce the coding difficulty and improve solution’s accuracy.An example is given to explain the process.In the end,further research orientation is discussed.

Abstract:This study firstly defines the arteriality of roads as an indicator to describe the relative importance of road in network topology,and uses betweenness centrality to calculate the arteriality of each road.Then a new method of road hierarchy is proposed by quantitatively calculating the arteriality of each road in the network.Finally,the reasonability of this new method is verified by a comparative study of the results of conventional road hierarchy method and this new calculation method.

Abstract:To calculate all parameters of passenger flow distribution on urban rail transit (URT),the paper fiirst presents a method to predict the origindestination (OD) distribution.Then,based on an analysis of the law of passengers’ flow between platform and train,platformtrain passenger exchanging model is established.Finally,the realtime algorithm to predict passenger flow distribution on urban rail transit line is obtained,the algorithm is validated with a case study.

Abstract:To study the influence of differential subgrade settlement on the ballasted track settlement,a 1∶1 model test was designed.The differential subgrade settlement was simulated by designed void,and the dynamic train load was simulated by Centrifugal Exciter,then a study was made of the influence of differential subgrade settlement on the settlement of ballasted track before and after the sleeper is unsupported on the condition that the the settlement of ballasted track was stabilized.Experiment result shows that the curve of track settlement caused by differential subgrade settlement can be described by cosine function.When the area of differential subgrade settlement curve is small and doesn’t cause the sleeper to be unsupported,the ratio of the area of track settlement curve to differential subgrade settlement is 1.Based on those results,the calculation formula which is about ballasted track settlement caused by differential subgrade settlement is put forward,then the main causing factors are discussed.With the developing of differential subgrade settlement,once the ratio of the area of track settlement curve to the area of differential subgrade settlement is less than 1,the phenomenon that the sleeper is unsupported will appear and the ratio of area will decrease as the increase of differential subgrade settlement.

Abstract:Under the condition of inconsistent fault diagnosis information,fault diagnosis reasoning fusion strategy integrating rough sets and evidence theory method for trainground wireless communication unit of communicationbased train control (CBTC) is proposed.By using rough sets,redundant part of characteristic data is eliminated and irrelevant indispensable characters are extracted.Then,a decision network with different reduced levels is constructed to denote the fault diagnosis problems of the trainground wireless communication (TGWC) unit by way of the definition of the rule confidence and coverage degree.Finally,a fault identification mechanism based on evidence theory is presented to process fault data collected by various sensors and exactly match them with diagnosis rules.Results show that with the diagnosis model,the ability of model fault diagnosis is improved with strong practicality.

Abstract:The profile of ammonia monooxygenase encoding messenger ribonucleic acid (amoA mRNA) was examined due to inhibition by Cu2+ (10,20,50 mg·L-1) during a short reaction period(10hour).The test was performed by several continuously fed nitrification reactors and the realtime reverse transcriptionPCR method was applied to detect change character of amoA mRNA.The Cu2+could affect amoA mRNA copies in activated sludge,and higher concentration of Cu2+would lead to more inhibition for amoA mRNA level.The decrease of amoA mRNA was more early observed before decrease of nitrifying rate.After mRNA inhibition happened,a lagging time prior to notable decrease in nitrifying rate was detected.So the nitrification inhibition was likely performed thought impact on transcription of amoA mRNA by Cu2+.

Abstract:Effects of extracellular organic matter (EOM) on algae coagulation removal were investigated with different types of flocculants.Different flocculants varied in their effects on coagulation performance and algae removal efficiencies.EOM could both beneficial and harmful effects on the coagulation.At the beginning of coagulation,EOM unified the flocculant,and subsequently reduced the effective dosage and hindered the charge neutrality of the flocculant.In the later period of coagulation,EOM could strengthen the adsorption bridging and entrappingsweeping functions,and thus made the floc more closegrained and improved the settling property.Results show that EOM can aid the coagulant to remove algae when combining with flocculants.When the concentration of EOM fell within 3～5 mg ·L-1,the effects of coagulation on algae removal is optimal.In short,the addition of EOM can decrease the flocculant dosage and enhance the efficiency of algae removal when it is used properly.This study provides practical suggestions on the technical modifications of flocculants in blue algae removal.

Abstract:The combustion characteristics and the variation of incylinder reaction species were investigated for DIdiesel engines with various fuels (diesel,toluene,cetane,dodecane,nheptane and iheptane) using computational fluid dynamics (CFD) technique.Meanwhile,an analysis was made of the correlation between the rate of heat release and reaction species.The results show that,the model is reasonable and the calculated values of incylinder pressure keep in accordance with experimental ones in references.Compared to other fuels,for toluene,four species (H,N,OH and O) generated in combustion process,incylinder pressure,rate of heat release and accumulated heat release are the highest.In addition,as to various fuels,the amount of OH species generated is also the highest.

Abstract:In an airbreathing proton exchange membrane fuel cell (PEMFC),the air flow effect is different on the strongly coupled temperature and humidity,and uncertain on the stack voltage.To study the stack performance in detail,the inlet hydrogen pressure and the rotation rate of fans are investigated as effect factors,and the orthogonal experiments are carried out at the corresponding working points.The results show that,when the fans rate is above the optimal value,the air takes more water from the cathode away and the membrane becomes dried slowly,and then membrane impedance increases,therefore the stack voltage declines; in the other hand,when the fans rate is below the optimal value,the heat quantity carried out with air is reduced,making the cathode surface temperature higher,the air relative humidity decreases rapidly,and then the membrane dries quickly,therefore the stack voltage drops sharply.Therefore,there is an optimal fans rate value which makes the stack voltage highest at each working point.

Abstract:The safety of the railway vehicle is mainly evaluated by the wheel/rail interaction forces.A wheel/rail interaction forces continuously measuring system for a 1∶5th scale roller rig in Tongji University is developed.The finite element method analysis and experiment studies are carried out to find the desirable positions of strain gauge on 1∶5th scale wheelset.Then an instrumented wheelset for continuously measuring wheel/rail interaction forces of 1∶5th scale roller rig is developed.The lateral forces are measured directly from the strain gauges on the wheel plate.A simple cosine strain gauges bridge and a direct current strain gauges bridge are practised on left and right wheel respectively.The wheel/rail interaction vetical forces are indirectly calculated according to the axle bend moments and lateral forces on wheels.The output characteristics of all strain gauge bridges are obtained through static calibration and the prcision of cosine gauges bridges is better than that of direct current gauges bridge.Finally the wheel/rail interaction forces of 1∶5th roller rig are given by this measuring system.

Abstract:The sources of the flux error were analyzed,and the theoretic flux error region was proposed in the motor control based on the space vector pulsewidth modulation.The harmonic distortion factor formula was deduced through the ripple current on the microscopic level (switching period) and macroscopic level (fundamental period).Finally the formula was analyzed,and some essential characteristics of the random zerovector distribution pulsewidth modulation (RZDPWM) were revealed.The simulation results verify the theoretic analyses.The results show that the performance decreases with the modulation index reaching the maximum value,the meansquare value is highly dependent on the numerical characteristic of the random variable,and the random movement of the error triangle along the flux/current circle is the key element that makes the spectrum expanded.

Abstract:According to the energy transformation of the dielectric electro active polymer(DEAP) from mechanical energy to electric power,the electric power generation mechanism is studied on the DEAP.The mathematical model for simulating the deformation of dielectric elastomer is set up on the basis of the MooneyRivlin model,and the dynamic characteristic of the material is discussed under different working conditions.Meanwhile,DEAP is analyzed in the staticelectric field on the forces,scavenged energy equation and motion equation.With the Danfoss DEAP material,the prototype is set up for harvesting energy from the wind.Quantitative experiments and research as well as detailed analysis show that the DEAP can generate the electric energy harvesting from the environmental sources.

Abstract:The paper presents a line search filter sequential quadratic programming(SQP) method for inequality constrained optimization.Compared to traditional SQP methods,the advantages are that the quadratic programming (QP) subproblem is always consistent and the penalty function is not required by filter strategy.Under some mild conditions the global convergence can be induced.

Abstract:The paper presents a study of the existence of positive solutions for a class of nonlinear second order impulsive differential systems with two parameters and the nonexistence of positive solutions,where the nonlinear terms have different properties and their coefficients a1(t),a2(t) are LPintegrable.By applying the theory of the fixed point index and constructing a special cone,the existence theorem of positive solutions is proved when parameters λ and μ have different conditions,and the nonexistence theorem of positive solutions is proved while λ is sufficiently small.

Abstract:The heat equation on Khler manifolds with nonnegative and bounded bisectional curvature was studied.The gradient estimate of positive solutions and the complex Hessian estimate on it were obtained under a less condition.

Abstract:Helmholtz resonator is a sound resonant system,which can consume the external sound excitation.It’s an important sound absorption structure,and can be used as the sound absorption wall in the museum and cinema.A two dimensional array of Helmholtz Resonators was designed,and the finite element method was used to calculate the sound transmission properties.The results show that,such a structure may present the Bragg’s scattering mechanism,local resonance mechanism and the Helmholtz resonance mechanism.Compared to the two dimensional acoustic crystal which is composed of tubes without openings,the structure proposed possesses wider acoustic band gap.So,the noise barriers,acoustic lens can be designed based on such structures.

Abstract:This study treats large and complex project organization as a dynamic and complexrelated social network.An analysis was made of the difference of project management concepts from social and traditional perspectives and the organization network model factors of large and complex projects by social network analysis (SNA), meanwhile,a study was made of the related basic models and modeling methods.The related model was established based on empirical analysis of Expo 2010 Shanghai.Based on the calculation and analysis with Ucinet software as well as a comparative study with traditional formal organization structure,the paper presents the conclusion and suggestions on organization management and control.

Abstract:In order to solve the contradiction of the nontradable share in China’s securities market,some listed companies issue an innovative warrant to compensate the tradable share holders.This innovative warrant is tied up with the stock,as a result,the return of the stock can not be assumed to present a geometry Brownian motion.To price the innovative warrant,the structural approach is adopted and the assets of the firm is regarded as the basic variable,the pricing formulas are obtained for the innovative warrant in both the cases with or without insurance.Theoretical and numerical analysis are made of the impact of different market variables on the price of the innovative warrant.