Abstract:Layer wind force interference characteristic of disturbed building is studied by rigid model pressure test, and this paper presents the along wind layer wind force interference characteristic. A study is made of the distribution of along wind layer wind force and its interference factors by arranging interfering building in different positions. The fitting formulas describing the characteristic of along wind mean layer wind force interference factors for side by side and tandem arrangement are obtained. The results show that the distribution laws of layer wind force and layer wind force interference factors change with the position of the interfering building. Maximum interference factors of along wind mean layer wind force and root mean square(RMS) layer wind force are found to be 1.08 and above 1.5 respectively.

Abstract:This paper, based on a model experiment of 1/2 reduced scale, reveals the stress mechanism of exposed steel anchor box cable tower anchorage and analyzes the effect of the prestress. The results show that the exposed steel anchor box cable tower anchorage is suitable for the cable stayed bridge of small span. In the condition of no crack occurred in the concrete tower wall, prestress does not change the distribution of the horizontal cable force between the steel anchor box and the concrete tower wall. Prestress can obviously reduce the tensile stress of concrete tower wall and then improve the performance in crack resistance. However, prestress will also reduce the ratio of utilization of steel anchor box and add the shearing force of studs.

Abstract:Fast Lagrangian analysis of continua in three dimension (FLAC3D) was employed to investigate the effect on pile foundation after a staged excavation, which considered the relative slip between pile and soil and also realized the dynamic process of excavation, and the model was verified by the results of axial force changing in pile shaft, the maximum tension force in pile and its location through the comparative analysis between the measurement and calculate after the excavation, and then the impact on the bearing capacity of pile foundation was discussed. Results show that pile foundation is in tension state after excavation, the maximum tension is increasing and the location is moving downward with the excavation depth; the bearing capacity changes significantly after excavation, the normal stress along pile shaft decreases sharply after excavation, especially on the pile top, which will cause the loss of bearing capacity in pile foundation.

Abstract:Taking one large deep excavation as the research background, this paper compares the effect of deformation control of the frame top down scheme and the traditional top down scheme through centrifugal model tests. In addition, it further studies the relationship between the maximum wall deflections and the maximum ground settlements, as well as the size and scope of ground settlements. The test results show that the excavation induced maximum ground settlements using frame top down method δvm is 0.35～0.7 times of the excavation induced maximum wall deflection δhm, and unsupported exposure time has some effect on δvm/δhm. The predicted results by empirical prediction method based on measured data is much different from the test results. Excavation induced performance using frame top down and traditional top down construction schemes is similar, and the excavation induced performance using frame top down scheme can be controlled effectively. The conclusion of this paper has significant referential meaning for designs and constructions of actual engineering.

Abstract:Beach nourishment project, involving both beach nourishment and submerged sandbars construction, will be carried out on Tiger Rock Beach. Based on finite volume method, the software Mike 21 is employed to establish a 2D flow and wave model of study area. Simulation results of the models are minutely verified by a comparison with the measured hydrodynamic data in 2011. Furthermore, the model efficiency is evaluated. Results show that the computation processes of tidal level, current coincide fairly well with field data, and with a high accuracy. This paper focuses on the influence of beach nourishment project to the surrounding current and wave. The levee of the submerged sandbars, where is the largest variation of velocity and significant wave height occur, is an additional sand source for artificial filled sands backyard with the long term dynamic loads. For the weak current and little wave change, the beach nourishment combining artificial filled sands and submerged sandbars is advantageous to save filled sands on the beach.

Abstract:A 3D finite element model of a base disengaging pavement structure was built for dynamic analysis. The effects of disengaging area, gap height and base cracking on deflection basin were analyzed and characteristics of deflection basin for a base disengaging structure were compared with other base damages. According to a correlation analysis, DR4 and AREA4 were proposed as judging index for identification of base disengagement. Based on an assumption of defects dispersion, relationship between disengaging area and equivalent modulus decrease was analyzed and an empirical model in estimating disengaging area was put forward.

Abstract:The relationship between the rutting life of asphalt pavement and its average temperature, temperature gradient were analyzed. The distribution of compression stresses for asphalt surface layer was discussed. Based on the pavement temperature field data collected at 90 areas in China over the years, the corresponding rutting equivalent temperatures were calculated and analyzed, the correlation between the standard rutting equivalent temperature and annual average temperature and difference of the highest and lowest monthly average temperature were summarized. Hence, the standard rutting equivalent temperatures for asphalt pavement at 738 areas in China were calculated, for design purpose, a contour map of the standard rutting equivalent temperatures was initially proposed. Moreover, the influences of various factors in the non standard conditions on the rutting equivalent temperature for asphalt pavement were analyzed, and a set of approximate formulas were given accordingly. At last, through a comparative study, the reliability of the calculation method and corresponding results were validated.

Abstract:Accorling to the characteristics of the panel data of the pavement condition index(PCI) field data collected from different sections, a two linear mixed effect model was established with an extension of a three order polynomial by employing the fixed effect and random effect as random parameters to predict the airport pavement performance. The parameters were estimated by the mixed effects approach. Results indicate pavement sections’ heterogeneity may be captured not only through mixed effect but through random effect as well, which makes up traditional regression model’s deficiency and provides a more appropriate method for analyzing multi sections pavement performance data. At the same time, the effect model can use multi sections pavement information and improve individual’s estimation, therefore, it can estimate individual pavement condition which has little time series with a significant higher accuracy in predicting specific pavement conditions in comparison with ordinary least squares(OLS).

Abstract:Coordinated control on arterial need to know about the relationship of transmission and change in the upstream and downstream on arterial. The traditional prediction of travel time or arrival distribution does not provide sufficient reference. According to the road conditions, some critical sections on arterial are defined. The arrival flow profile on critical sections are drawn by collecting actual vehicle detection data or simulation experiment data and the statistics of the arrival distribution at different periods corresponding to the intervals by time step. The impact of arrival flow profile by segment dispersion and signal control is analyzed. On the basis of the speed cumulative probability distribution, transition matrix is calculated, and the prediction method of arrival flow profile considering segment dispersion is proposed. Based on an analysis of the traffic dispersion process on green and the queuing on red, the prediction method of arrival flow profile considering signal control is proposed. Simulation studies show that the relative error of the predicted arrival flow profile is smaller, which validates the prediction methods.

Abstract:Oxidation of Microcystin LR (MC LR) in background of Microcystis aeruginosa intracellular organic matter (IOM) and extracellular organic matter (EOM) by potassium permanganate was studied. MC LR degradation followed second order kinetic with the rate constants of 368.3 and 400.2 (mol·L-1)-1·s-1 in EOM and IOM background respectively. Meanwhile, pre oxidation of Microcystis aeruginosa by potassium permanganate was studied. The impacts of permanganate dosage and reaction time on quantum yield, release of intracellular MC LR and other featured organic matter were investigated. The release of intracellular MC LR and decrease of quantum yield both followed second order kinetic with turning point at permanganate exposure respectively. Permanganate mainly reacted with EOM and the cell bounded organic matter before exposure value arriving quantum yield turning point. Thereafter, permanganate directly reacted with cell wall of algae causing the rapid reduce of quantum yield with the rate constant greatly increased from 0.49~2.35 (mol·L-1)-1·s-1 to 5.00 ~19.38 (mol·L-1)-1·s-1. Similarly, MC LR was slightly released while permanganate exposure value below release turning point, where algae cells kept relatively integrated. Subsequently, algae damage occurred after the release turning point, inducing mass of intracellular MC LR release with the rate constant greatly increased from 0.55~1.45 (mol·L-1)-1·s-1 to 0.96~14.45 (mol·L-1)-1·s-1. Humus like peak was observed emerging at quantum yield turning point and becoming evident at release turning point, which is very similar to the pattern of quantum yield dropping and intracellular MC LR releasing.

Abstract:The investigation mainly focused on the utilization of fatty acid ester by B. subtilis ATCC 6633 to synthesize lipopeptide. The results show that lipopeptide can be synthesized by using 6 kinds of edible oil as carbon source. When olein, the main composition of edible oil, was chosen as the carbon source , the yield of lipopeptide was enhanced from 95 mg·L-1 to 183.5 mg·L-1 under the action of glutamic acid (Glu). Through stable isotope probing, it was confirmed that glycerol, the hydrolysis product of olein, was of better use by the bacteria . With Glu addition, the utilization rate of fatty acid ester was improved and more carbon source was used to synthesize lipopeptide ,while Glu was mainly used to synthesize the bacteria, thus biomass and the yield of lipopeptide were enhanced.

Abstract:Urban water supply network is of critical infrastructure. In the process of water distribution network planning, operation management and optimization scheduling, it needs to understand the hydraulic and water quality status of water distribution network comprehensively. The establishment of water distribution network hydraulic model is the most effective method. In this study, Sobol’ sensitivity analysis method is selected to analyze the parameter sensitivity in the model, then a real water supply network is taken as an example for automatic calibration. The results show that with Sobol’ sensitivity analysis method and NSGA Ⅱ algorithm, calibrating the pipe friction factors which have higher sensitivity, can reduce the number of decision variables and calibrating time.

Abstract:The paper presents an algorithm for the location of sudden bursts in combination with both continuous monitoring of pressure and hydraulic model computation. The Cuckoo Search, genetic algorithm and particle swarm approaches were employed to identify the location of leakage. Their performances were compared. The results show that the Cuckoo Search has a better performance in terms of searching speed and parameter requirement among the three optimization algorithms. The case study results reveal the potential of the proposed burst location identification technique in a real life water distribution system.

Abstract:A lightweight material with cement and expanded polystyrene (EPS) is prepared by compressing semi dry materials molding. The stress strain curve is achieved by compression test. The absorptions of impact force and impact energy during impaction are tested by a self made device when two different impact energies are applied. Relationship between impact force absorption, impact energy absorption and cement dosage is analyzed. Effect of fiber and latex on absorption is discussed. The results figure out that this material has a different fracture from normal EPS concrete. Upon compression, the material will reach strain of 0.6 without brittle fracture which represents brilliant toughness. Impact force absorption decreases first and then increases with the rising of cement dosage, while adding fiber and latex can lead to higher absorption. Impact force absorption increases first and then decreases with the rising of cement dosage, while adding fiber and latex can lead to higher absorption on low cement dosage but lower absorption on high cement dosage. The influence law and mechanism of various factors are analyzed in detail.

Abstract:In order to facilitate the development and application of air entraining agents (AEA) in the high performance concrete, entrained air void structure parameters of 28 d concrete were measured by image analysis method. The relationship between the air void size distribution and strength of concrete was studied with the method of grey connection analysis. In addition, the effect of air voids on the paste aggregate interfacial transition zone (ITZ) was analyzed by Microhardness. The results show that the correlation between different pore size range and the compressive strength is negative. The effect of air void size distribution on 28 days compressive strength is different: under the condition of similar total porosity, with the increase of the porosity of the air void size, ranging from 10 μm to 200 μm, and the decrease of the porosity, ranging from 200 μm to 1 600 μm, the average air void diameter and mean free spacing are decreased; as well as the width of ITZ. On the contrary, the microhardness of the ITZ is increased while the compressive strength loss is decreased.

Abstract:Unregulated emissions of CO2,CH4,N2O,SO2 and aldehydes were tested on a common rail China stage V diesel engine fueled with diesel(D100) and butanol diesel blends. Without any modification to the engine, five different blends were tested to analyze the effect to unregulated emission by the ratio. The volume ratios of butanol were 0,10%,20%,30% and 50% respectively. The results show that in comparison with D100, the blends’ emission of CO2,N2O,SO2 and aldehydes increase and all of them present a trend of rise under the full load condition.With the ratio increasing, all of the fuels have a low emission of CH4. At the maximum torque speed 1 400 r·min-1 and rated speed 2 200 r·min-1, the blends’ emission of CO2,N2O,SO2 and aldehydes increase with the increasing of the load,CH4 is below 1.0×10-6.

Abstract:The research on two stage spray strategy of quick start of one gasoline direct injection（GDI）engine is studied by using the computational fluid dynamics (CFD) method. The result shows that，earlier first injection timing will cause much more oil film on the surface of piston and less fuel evaporation which may lead to dilute mixture in cylinder and the ignition requirements can’t be met. Then later first injection timing may result in more rich mixture being detained in the exhaust valve pit which will lead to more hydrocarbon emissions. The first spray timing should be set from 270° CA BTDC(before top dead center) to 240° CA BTDC. Compared to the first injection, the influence on oil film of second spray timing during compression process is little. The injection timing earlier 90° CA BTDC may cause more crash between droplets and cylinder liner. According to the simulation results, the second injection timing should be set after 90° CA BTDC.

Abstract:The frontal view, top view and cross sections of low drag car body were parameterized with control points and curves. Then the two dimension car body was optimized by design of experiments and local refinement methods. The global optimum results were obtained. Two three dimension car bodies without wheels were built based on the optimized two dimension car bodies，and their coefficients of aerodynamic drag were as low as 0.057 and 0.089 respectively. They could serve as low brag basic bodies for the future research of an ideal car. The agreement between test results and numerical results indicates that this parametric modeling method of low drag car body is feasible.

Abstract:The frictional squeal of brake shows significant uncertainty characteristics. A bench test was carried out on a vibro acoustics test rig of brake to study the uncertainty of the brake squeal. So, a novel squeal confirmation and determination method based on time frequency analysis results, which could show the squeal variations in the domains of time, frequency and amplitude together, was presented. An uncertainty analysis flow chart was also established, in which statistical indexes of squeal frequency and sound pressure level, and probability density evaluation of frequency based on Quantile Quantile Plot（QQ plot）, were given. And a judgment method of frequency doubling was devised based on numerical multiple and occurrence concurrence, as well as the uncertainty statistical analysis method with a consideration of the frequency doubling. All the methods established were applied to the uncertainty analysis of brake squeal. It is found that, both squeal frequency and sound pressure level are dispersed, and each squeal has its own statistical results. The probability density of either squeal frequency approximates to normal distribution, while the frequency decreases as the corresponding sound pressure level increases. There are both the same and different squeal frequencies under drag module and in stop module, whose frequency and sound pressure level statistics are also different.

Abstract:Focusing on the dividable batch tasks running in the cloud computing environment, a study is made of the resource virtualization based on time division multiplexing in order to ensure a fair opportunity for users in cloud computing with multi tenants and satisfy the requirements as much as possible. Computational resource in cloud system is viewed as the time multiplexing object. According to users’ requirements, the appropriate multiplexing cycle and time slices are determined with the proposed strategies. Furthermore, a detailed performance analysis for different strategies is made. Theoretical analysis and simulations prove the time division multiplexing resource management method to be valid.

Abstract:Based on the scalable vector graphics(SVG) format, an analysis was made of the temporal geographic information system(GIS) field, especially current research status of geographic element query, and then a comparative study was made with the existing extensible markup language(XML) query methods. A SVG grammar rules based research was proposed. In combination with the LISA Ⅱ query technology, a query model and the corresponding algorithm applicable for the GIS data geographic element of the improved rules SVG format were proposed. A combination query was achieved by defining keyword query syntax regular expressions and the keyword query “&” and “or” operation rules. In addition, the number of nodes was reduced, and the query efficiency improved by defining the entity element node. Study results show that the model achieves geographic elements queries of SVG format map, including various combinations queries on the entire map and various combinations queries of layers. As a result, the technical bottleneck of query is solved based on SVG format map elements. Lots of data validate this query model is effective.

Abstract:We propose a nonmonotone guadratic programming free(QP free) infeasible method without using a penalty function and a filter for inequality constrained nonlinear optimization problems. This iterative method is based on the solution of nonsmooth equations obtained by the multipliers and the nonlinear complementarity problem(NCP) function for the Karush Kuhn Tucker(KKT) first order optimality conditions. Locally, each iteration of this method can be viewed as a perturbation of the mixed Newton quasi Newton iteration on both primal and dual variables for the solution of KKT optimality conditions. We do not use a penalty function and a filter on nonmonotone line searches to avoid the estimation of the penalty parameter and the storage of the filter. The step size is selected so that either the value of the objective function or the measure of the constraint violations is sufficiently nonmonotone reduced. The trial step is more flexibly accepted. It does not demand the strict feasibility of the iterations including the initial point. This method is implementable and globally convergent. Without the second order correction we prove that the method has superlinear convergence rate.

Abstract:This paper presents a differential flow concerning the global optimization with polynomials. Along the flow which leads to a global minimizer there is posed a mixed difference algorithm with Newton method. An error analysis of the algorithm is given with a numerical example to demonstrate the mixed difference method.

Abstract:Cadzow filtering is a well known denoising technique in the seismic signal processing. This method first transforms the data measured in seismic remote sensing into a complex Block Hankel Hankel Block (BHHB) matrix， then it reduces the noise via singular value decomposition (SVD). Usually, the structure of BHHB matrix is ignored in the SVD computation， so that the computational time and memory storage are high especially when the size of matrix is large. This paper presents a fast and stable SVD algorithm for complex BHHB matrices. The fast SVD algorithm consists of two stages: Lanczos bidiagonalization (or tridiagonalization for symmetric BHHB matrix) and diagonalization using twisted factorization. By exploiting the structure of BHHB matrix, the SVD can be accelerated by a fast matrix vector multiplication based on the 1 D Fast Fourier Transform(FFT). Compared to the multi dimensional FFT implementation, the proposed method requires much less memory with the similar computational cost. Numerical experiments support this claim. Finally, the fast SVD method is applied to some seismic examples with the Cadzow filtering technique to reduce noises. It turns out that the proposed method is better than the prediction filtering and it is cost efficient in the speed and memory usage in seismic data processing, especially for large problems.

Abstract:TiO2 coated diatomite samples were prepared by sol gel method first, and then the Diatomite/TiO2/TiOx pearlescent pigments with uniform smooth and dense coating layer were prepared by precursor precipitation. The effects of pH and calcination temperature on the morphologies of the final Diatomite/TiO2/TiOx products were studied. The results show that when pH value of the solution is 5.0, black titanium oxide particles are small, well dispersed, and the pearlescent pigments have a smooth and dense coating layer of titanium oxides on their surface. When the calcination temperature is 650 ℃, the coating particles are still small, resulting in the smooth and dense coating layer of titanium oxides. However, when the calcination temperature is 700 ℃, coating layer is still smooth and dense, but the coating particles become large.