Abstract:Laboratory tests were carried out to investigate the performance of lime and fly-ash inorganic binder stabilized steel-slag and crushed-stone aggregate mixtures for pavement base. The test results and analyses indicate that the unconfined compressive strengths of the mixtures increase significantly with the increase of slag content. In other words, the slag can reduce the use of the inorganic binder. The moisture induced expansion rate of combined aggregate can be controlled by changing steel-slag content, which must be considered in the material design. The slag can increase the indirect tensile strengths and compressive moduli of the mixtures. A content of 50% slag in the aggregate can increase the strength and modulus by up to 24% and 21%, respectively, resulting in layer thickness reduction in the designed pavement structure. The slag can decrease the dry-shrinking coefficient of the mixtures. A content of 50% slag in the aggregate can decrease the coefficient by up to 27%, resulting in moisture loss induced cracking alleviation in pavement base. The existence of slag has little effect on the water scouring properties of the mixtures, which does not have to be considered in the material design.

Abstract:Fatigue cracking in bridge deck and damage with asphalt pavement are severe issues to orthotropic steel bridge plates. In terms of the concept of the amelioration of the stress condition of the pavement, an innovative composite bridge deck system composed of orthotropic steel decks and a Reactive Powder Concrete (RPC) layer was proposed. The longitudinal partition test and lateral bending tests clearly illustrate that the bending tensile strength of this composite deck structure considerably exceeds the design stress, and its weight is approximately equal to those of the traditional pavement. Furthermore, the results of lateral bending tests adequately demonstrate that the bending strength of this new system is dependent on the reinforcement ratio and the effective height of the section. As the reinforcement ratio is doubled and tripled,the bending strength is enhanced by 15 and 40 percent respectively. Similarly, the bending tensile strength increases by 30 to 50 percent on various reinforcement ratios when the effective sectional height is climbed by 20 percent. Consequently, the risk of crack or damage during bridge operation period will shrink substantially as the improvement of reinforcement ratios and the effective height of the section.

Abstract:Considering the influence of large deformation, the non-linear dynamic equations of a high pier under the foundation ellipse motion caused by Rayleigh wave by earthquake were established. By supposing the displacement shape function and applying the Galerkin method, the dynamic equations about time were obtained. By processing numerical calculation, the displacement response curves of the high pier under the foundation ellipse motion with different magnitude and the overall process from the transverse vibration to the instability of the high pier were given. The critical seismic acceleration and the instability time were obtained. The influence of different seismic peaks, the slenderness ratio and the weight of the bridge on the displacement response, the critical seismic acceleration and the instability time were analyzed.

Abstract:When a parallel arranging prestressed steel wire is used to strengthen concrete bending slabs, the cost is too high if the steel wire is covered with high tensile strength composite mortar. Aiming at this, a new strengthening method was proposed, in which was combined with pre-tensioning prestressing steel wire,and common high-strength cement mortar was used to replace post-tensioning the former mortar. This method can prestress on the tension zone of the concrete slab and cover the mortar layer. And the feasibility of the strengthening principle and construction technology were demonstrated by strengthening the experimental study and numerical analysis about the model test of a reinforced concrete bending slab, which shows that the premise is to spray epoxy interface agent on the joint surface in order to ensure that the joint surface does not produce detachment of the destruction. So this method can avoid using expensive high tensile strength composite mortar, the strengthening cost can be reduced, and the mechanical properties of cross-section after reinforcement can be enhanced.

Abstract:Based on market comparison approach, a new interval numbers grey fuzzy method of real estate appraisal was proposed.The interval number was used in real estate appraisal, and the gray system theory was used to choose the main factors influencing the real estate price. Finally, the fuzzy comprehensive judgment method was used to get real estate appraisal. An example shows that this method has higher precision and is effective and practical.

Abstract:An unsteady siphon flow model with two initial nature dynamic flows was established. The property of the unsteady siphon under different initial conditions was analyzed by applying Computational Fluid Dynamics (CFD). The siphon import cumulative momentum analysis results show that the dynamic initial flow conditions have an obvious impact on the property of unsteady siphon flow. Based on the results of CFD, an optimal solution of initial flow conditions was obtained by GA-ANN method. It provides a reference to the design of siphon runner and the research of unsteady siphon flow.

Abstract:Based on the seven point central dispersion relation preserving (DRP) space discretization scheme, and combined with five kinds of Runge-Kutta time integration scheme, the dissipation and dispersion errors induced by time and global discretization schemes, the effective wave number ranges, the error propagation of long distance, the accumulated error of low, middle and high frequency wave were analyzed by using traditional Von Neumann method and a new correct error propagation method from three aspects, i.e., error component, error propagation, and error accumulation. In addition, the advantage and disadvantage of all the combined schemes were compared by analyzing their stability and accuracy. The accuracy of ORK6 time integration scheme combined with seven point central space discretization scheme was the highest among these combination schemes. Finally, a few numerical tests were presented to show the accuracy of these schemes in simulation of one dimensional scalar and vector wave motion.

Abstract:Due to complex driving conditions in cities, it is hard to obtain the optimal economic performance with the rule-based strategy alone. An adaptive real time control strategy was proposed to adapt the various driving conditions and to improve fuel economy of a new series-parallel hybrid electric bus (SPHEB). This method consists of the Equivalent fuel Consumption Minimization Strategy and algorithm of driving pattern recognition in essence. The key role of ECMS is the equivalence factor, which is used to convert electrical power used into an equivalent fuel quantity. Four types of roadways were selected to present the characteristics of city driving cycle， and a driving pattern recognition approach was employed to obtain better estimation of the equivalence factor under different roadway types. The main idea of the adaptive real time control strategy is periodically updating the equivalence factor dependent on the corresponding driving condition. To validate the proposed strategy, a forward model was built on the basis of simulink. The simulation results demonstrate that the roadway types can be successfully recognized and the improvement of fuel economy is up to 8.55%, while the battery SOC is limited in the desired range.

Abstract:With the Wuhan-Guangzhou high speed railway traction substation as the research background, the effect of high-speed railway traction power supply system on real-time power grid operation was studied, and PSCAD was applied to build suitable traction power supply simulation system for high-speed railway. Jiles-Atherton ferromagnetic hysteresis principles were employed to establish transient model of the V/v traction transformer. The piecewise linear U-I curve of UMEC model was equivalent to the saturated characteristics of the iron core, and then, no-load closing simulation was done. On this basis, simulation of single-phase short circuit fault and switch-in with load was done in time of three-phase short circuit fault in line side. The simulation results verify the practicality and validity of the traction transformer's transient model and traction power supply simulation system, which provides a reliable theoretical basis for the related operation departments.

Abstract:A RF power amplifier was designed for WLAN 802.11 b/g 2.4 GHz based on 0.18 μm SiGe BiCMOS technology. The PA consists of three stage amplifiers working in Class AB. Adaptive bias circuit based on current mirror was used, with temperature compensation and linearization. The post-layout simulation results showed that the designed power amplifier had an output of 1 dB, a compression point of 27.73 dBm, a power gain of 25.67 dB, an S22 of less than -10 dB and an S12 of less than -60 dB in 2.4 GHz.

Abstract:The micro-arc oxidation of ZK60 magnesium alloy was carried out in silicate electrolyte systems with different electric parameters. Through experimental analysis, the results are as follows: Time has a greater impact on the corrosion resistance of the coatings. When the film grows to a certain thickness, the corrosion resistance of the coating declines with the increase of time. With the increase of current intensity, the morphology of the coating becomes rougher， the micro hole becomes bigger and micro cracks are evident. The concentration of KF in the electrolyte has a great influence on the quality of PEO films. With the concentration of 12 g/L KF in the electrolyte, the thickness of the film is nearly twice of the film without KF addition, and the corrosion resistance of the film has also been greatly improved. When the concentration of fluoride is too high, the film is easy to delaminate from the sample surface. The addition of nano-SiC particle in the electrolyte has no obvious effect on the corrosion and thickness of the micro arc films.

Abstract:Multiferroic Bi1-xDyxFeO3 with different amounts of doping Dy was prepared in the Sol-gel method. The phase，microstructure and morphology of the samples were characterized with XRD and SEM, respectively. The electromagnetic parameters and microwave absorbing properties were measured respectively in transmission/reflection technique and arc method under the network analyzer system. The optimal calcined temperature was confirmed on the basis of the analysis on the effects of calcined temperatures on microstructure and morphology. Further studies were carried out with regard to the influences of Dy-doped contents on microstructure, complex permitivity and permeability，electromagnetic loss mechanism and wave absorbing properties. The results indicate that the particles are short fibers in submicron and impurity phases disappear under the calcined temperature of 850 ℃. The doped Dy can effectively restrain the formation of the impurity phase, volatilization of Bi3+,and spiral spin magnetic structure. Therefore, the complex permitivity and relax strength of the permeability spectra are improved. Due to the coexistence and competition of dielectric and magnetic loss mechanism,Bi1-xDyxFeO3 with doping Dy can improve absorbing ability in high frequency ranges.

Abstract:To realize effective nitrogen and phosphorus removal and phosphorus recycle, a new system combining chemical phosphorus removal technology and anaerobic/anoxic/nitration (A2N) process was proposed. Experiments were done to compare the characteristics of nitrogen and phosphorus removal in A2N and A2N-induced crystallization (A2N-IC) processes. The results showed that, when the influent total phosphorus (TP) concentrations were 5.22~8.31 mg/L-1, the TP removal efficiencies of the A2N process and A2N-IC process were 87.4% and 99.6%, respectively. The TP removal efficiency and the stability of A2N-IC process were obviously better than that of A2N process. The ammonia removal efficiencies were 84.8% and 84.4%, and they were nearly the same. The main reason for the high stability and TP removal efficiency in the A2N-IC process was that chemical phosphorus removal provided assistance to the biological phosphorus removal. The product in the induced crystallization reactor was hydroxyapatite. Magnesium ammonium phosphate precipitation could not be formed.

Abstract:Fluent software was used to simulate the wind flow state and CO diffusion in submerged arc furnace during collapse, where a three dimensional k ~ ε model was adopted, and the effect of buoyancy was taken into consideration. The simulation results show that wind flow for each respiratory surface can be divided into three zones, namely, mainstream zone, eddy zone and stagnation zone. Eddy zones appear at chimney sites while stagnation zones can be found at the wall of mainstream outlet. From the analysis of CO diffusion and distribution at different wind velocities and directions, it can be concluded that CO concentration decreases from eddy center to periphery driven by mainstream entrainment. Regression analysis shows that ventilation time decreases exponentially with wind speed increase.

Abstract:A PDM (Parallel Data Mining) system was built based on Hadoop. PDM contains a large number of parallel data analysis algorithms based on MapReduce computational framework. These algorithms not only contain the classic algorithms of ETL, data mining, data statistical and text analysis, but also introduce SNA (social network analysis) based on graph mining. The principle and implementation of the parallel multiple linear regression algorithm and the multi-source shortest path algorithm were described and the “Message-passing model” proposed can effectively solve the problem that MapReduce is difficult to deal with the adjacency matrix structure. This paper also illustrates some typical applications of telecommunications, such as the “Business recommendation” based on parallel k-means and decision tree algorithms，the “Marketing key points discovery” based on parallel PageRank algorithm and the like. Finally, the results of performance test show that the proposed system is suitable for dealing with large scale data efficiently.

Abstract:Quick Response (QR) barcode is a quite common two dimensional barcode. Image preprocessing is a key step for the automatic recognition of QR barcode decoder. In order to lower the used threshold, a practical image preprocessing method was proposed for QR barcode recognition. It could increase the speed of recognition by this decoder so as to embed this algorithm into mobile terminals. It didn't utilize the traditional methods such as edge detection and line detection, but only the encoding characteristic of QR to locate, thus the influence of geometric distortion and background noise was reduced. Moreover, in order to improve the recognition rate, it used the rectification images to adaptively sample the QR code in terms of regions. Experiment results demonstrate that the proposed approach can overcome the influence of noise, inhomogeneous light and geometric distortion, and meet the requirements of real-time decoding.

Abstract:Based on the Petrochemical Industry, this paper put forward a decoupling model, and adopted LMDI (Log Mean Divisia Index) method to construct an influencing factor model of carbon dioxide emission, which explored the impacts of industry energy intensity, energy scale, energy efficiency and industrial structure on the carbon dioxide emissions from the Petrochemical Industry. The research indicates that Chinese Petrochemical Industry has gone through four stages: Strong negative decoupling (1999-2002), Expansive negative decoupling (2003-2007), Weak decoupling (2008-2009) and Strong decoupling (2010)，and has taken on low-carbon economical characteristics of"Strong decoupling".The result shows that energy intensity is a key factor influencing decoupling effect, while adjusting industrial structure has failed to show clear decoupling effect.

Abstract:Based on literature reviews and interviews with project managers, 20 factors were identified as critical success factors of construction supply chain under EPC, and the hypothesis was given. With development of questionnaire, the data was analyzed by the SPSS to verify the hypothesis, finding that 20 factors were critical and could be divided into five dimensions: strategy, cooperation, process, attitude and recourse. Finally, management strategies were suggested to improve the performance of construction supply chain.