Abstract:Data of material property uncertainty, geometrical uncertainty, calculation model uncertainty for overall stability design and load bearing capacity of short columns for Q235, Q345 coldformed thickwalled square and rectangular steel tubes were collected and on this basis, seismic and nonseismic design reliability analysis was conducted through the firstorder secondmoment method. Finally, the resistance partial factor and seismic adjustment coefficient of bearing capacity under strength and overall stability design for Q235 and Q345 coldformed thickwalled steel members were proposed for the reference in current revising of related design codes.

Abstract:A structural analysis was conducted on semi-rigid timber portal frame; formulas were derived in terms of the internal force and lateral stiffness, and the influence of the semirigid joint was discussed. Meanwhile, experimental tests were carried out on three fullscale timber portal frames and five bolted timber connections to study the lateral performance of the frames and the moment resistance of the connections. For consistency, the connections from the portal frames and the connections for bending tests were of the same configuration. Finally, a comparative analysis was made to verify the derived formulas.

Abstract:The uniform flow past two dimensional square cylinders with blockage ratios 4.2%, 10%, 16.7%, 20% and 25% were numerically investigated by largeeddy simulation (LES). The aerodynamic forces and pressure distributions of the cylinders with these blockage ratios were discussed. The blockage effects on flow field characteristics and instantaneous vorticity were investigated. The results show that when the blockage ratio increases from 4.2% to 25%, the average drag coefficient， fluctuating lift coefficient and Strouhal number increase by 27.6%, 43.6% and 31%, respectively. The mean suction pressure coefficients and fluctuating pressure coefficients on the side and leeward surfaces of the cylinder both increase with the blockage ratios. The blockage effects on the flow characteristics around the cylinders are significant. Furthermore, for high blockage ratios, periodic and alternating vortices are observed in the vicinity of the walls and mix with the vortices shedding from the cylinders.

Abstract:The cellular automaton (CA)based floor field model has been widely applied to addressing the issues concerning the 2D evacuation. It is found that the existing floor field models mainly focus on the behavioral features based on the location of the exit and following others in the lead, but the influence of fire expansion and local congestion is not fully considered, resulting in the inability to precisely simulate the evacuation process in such scenarios. In reality, the moving directions of occupants are heavily dependent on the expansion of fire, while the moving needs of occupants are remarkably influenced by the congestion in the adjacent pedestrian flow. Correspondingly, in this paper, the fire scenario based moving direction is proposed to describe the moving direction affected by fireinduced panic; the pedestrian flow based expected velocity is proposed to address the moving need affected by local congestions, in a bid to modify the present models. The parameter analysis based on the proposed model indicates that the overall evacuation time and the average death toll vary when considering the scenario based moving intention and expected velocity; the overall evacuation time will be underestimated while the average death toll will be overestimated if these two behavior features are not incorporated.

Abstract:Aiming at the situation that Boeing Bump will be the new method to evaluate airport pavement roughness in China, an analysis was made of the limitations to Boeing Bump's application. Boeing Bump was introduced in detail and the procedure of Boeing Bump Index (BBI) was developed meantime, based on ADAMS/Aircraft, the virtual prototype of typical aircraft was modeled, and with the field longitudinal profiles of 37 runways around the world, some problems of BBI and its criteria were explored. The results show that BBI has no ability to deal with multiple bumps on the runway, and is supposed to combine with some reaction evaluation index; some reasons, including the most unfavorable taxiing speed, single evaluation index and single evaluation aircraft, will make the criteria too loose, and the criteria of BBI should be corrected appropriately.

Abstract:An accelerated pavement test using 1/3 model mobile load simulator(MMLS3) on a 1/3 proportional pavement structure model has been conducted to study the antireflective cracking performance of geotextile under the combination of tensile and shear effect due to traffic load. The strain and crack propagation has been monitored during the test. Results show that: for geotextile group, the load cycles of crack initiation and penetration are 3.55 and 3.25 times as much as nongeotextile group, respectively. The total strain and elastic strain of geotextile group are higher than non geotextile group before crack initiation because of the reduction of interlayer adhesion. However, geotextile can help retard crack initiation by increasing the composite fracture energy combined with surface layer; after cracking, geotextile assists surface layer to endure the tensile and shear effect under traffic load with its increasing tensile deformation and tensile resistance, so the total strain and elastic strain of geotextile group decrease; after crack penetration, geotextile suppresses the horizontal propagation of the crack and the vertical displacement of the pavement structure by maintaining the connection of structure across the crack. Therefore, the total strain and elastic strain of geotextile group remain stable at 180×10-6 and 9×10-6 respectively. By contrast, the total strain and elastic strain of non-geotextile group exceed 600×10-6 and 8×10-6 respectively and continue to grow with the expansion of crack.

Abstract:Firstly, clumps were generated by using the convex hull algorithm and the Bubble Pack algorithm to simulate coarse aggregate particles. Then, asphalt mixture virtual samples were constructed by assembling virtual coarse aggregate particles and virtual asphalt mortars and creating voids based on the PFC 5.0 3D. Finally, the virtual triaxial shear test based on the servo control principle was carried out, and the laboratory test data and the virtual test data were compared and analyzed. The results show that based on the PFC 5.0 3D, when the clumps being used to characterize the coarse aggregate particles in the virtual sample of the asphalt mixture, not only the precision of clumps is controlled but also the surface structure characteristic is more realistic. The threedimension discrete element numerical model of asphalt mixture can effectively describe the mechanical behavior of asphalt mixture.

Abstract:Based on the realistic driving behavior data collected by Shanghai Naturalistic Driving Study, an automatic extraction algorithm was developed and 4 734 cutin events were identified. This study aims to make indepth analyses on the characteristics of cutin preparation, execution and its impacts on the following vehicle. The results show that cutins are mostly motivated by avoiding slow preceding vehicles in the original lane. Cutin duration and turn signal usage of the Chinese drivers are both less than those of the United States, which shows a more aggressive driving style. About 15% of the followers accelerate with a speed change rate of more than 10% in response to cutin behavior for their discourtesy or intolerance. Compared to freeways and expressways, the cutin behavior on surface roads has a greater impact on the following vehicles and it is more dangerous with higher risks.

Abstract:The intersitevehicle imbalance is a major puzzle which has seriously hindered the development of electric vehiclesharing. A set of reasonable vehicle scheduling scheme can solve this puzzle. Firstly, the minimum cost of scheduling demands model based on satisfying all the consumers’ demands was constructed with the genetic algorithm to solve the model. Secondly, after obtaining scheduling demands, a mixed integer programming model was proposed to optimize the dispatchers’ routes, and the branch and bound algorithm was used to solve the model. Finally, taking orders data of five specified sites as input for a case calculation. The calculation results indicate that in the situation of increased demand, if artificial scheduling strategy is adopted, the ability to accept orders can be increased by 60%. In addition, it can save 60% of the cost input comparing with increasing the number of parking spaces and vehicles.

Abstract:Unreasonable site location selection of intercity railway stations usually results in high investment and poor attraction of passenger volume. For that the previous studies neglected or simplified the calculation of broadsense travel utility in a city (a part of tripchain utility), the paper proposes an innovative model on the basis of the tripchain characteristics and employs the logit model to estimate the probabilities of various travel modes along the trip chain. A bi-level objective function based on the trip chain is developed to maximize the incomes of intercity rail operations (the upper level) and minimize the costs of passenger travels (the lower level). The improved particle swarm algorithm is utilized to find the optimum solutions. The results of the case study on the railway site location selections in Zhuhai City indicate that the Pareto optimum of model suggests the contradictive relationship between the objective functions at the upper and the lower levels, which is essential to identify the optimum tradeoff among the various demands of the rail stations. The model serves to provide a reasonable decisionmaking procedure for the planning of the railway site location selections in the future.

Abstract:Passenger choice behavior, which causes dynamic changes of the passenger flow distribution and leads to the spread of congestion, is one of the key factors of bottleneck for passenger transport capacity. An association network of facilities is set up based on the analysis of passenger service chain in station. Then the passenger flow distribution model with node capacity constraints is established considering the passenger choice behavior. The dynamic penalty function is introduced to solve this model. Based on the result of the solution, the identification of bottleneck for passenger transport capacity through the index of affected degree of nodes is proposed. Finally, a case study of Lujiabang Road Station in Shanghai is carried out and compared with the simulation results of StaPass, verifying the feasibility and accuracy of this approach, which can help to analyze the passenger flow distribution of metro station in different scenarios.

Abstract:In order to realize passenger pedestrian facilities flow assignment which conforms to pedestrian streamline network characteristics in the urban rail transit station, directional delaynode time impedance and node passenger flow direction were introduced into shortest path identification process. The above shortest path identification process was added to the method of successive averages and passenger flow assignment algorithm was constructed which is suitable for pedestrian streamline network in urban rail transit station. Corresponding passenger flow assignment software was developed by using C#.NET and Matlab in AutoCAD and the method to get node passenger flow direction was built in the development process. The example shows that the above algorithm can realize pedestrian facilities passenger flow assignment in urban rail station considering the directional delaynode time impedance, and, compared with TransCAD and VISUM, the above software conforms to pedestrian streamline network characteristics and is easy to operate.

Abstract:Line balancing problem and buffer allocation problem are often studied separately, but there is a complex interaction between them. Considering stochastic assembly line, the operating time variability exacerbates the interaction between the two problems. Optimizing sequentially is difficult to get the global optimal solution. Therefore, it is necessary to solve the two problems simultaneously. The probability distribution of operating time is measured as station complexity based on information entropy. An integrated optimization model is established. The optimization objectives are as follows: maximizing of the production rate and minimizing of the smoothness index of standard workstation time, the smoothness index of workstation complexity and total buffer capacities. Parametric modeling simulation is used to calculate production rate. An improved genetic algorithm is put forward to obtain integrated optimization solution. An instance of a gearbox assembly line is calculated and verified, which proves the effectiveness of the method.

Abstract:Based on the analysis of the performance of the classical mobility models and the characteristic in Ocean Fishing Vessel Opportunistic Networks (OFVON), this paper presents a Smooth Turn SemiMarkov Smooth Mobility Model (STSMS). An analysis is also made of the equation of node motion and stationary average speed, and then the trajectories and stationary average speed of nodes are proved by simulation. The results of simulation show that STSMS the established STSMS well coincides with the characteristic of node mobility and has not the attenuation characteristics as time increases. Thus，STSMS model can be applied to simulation of OFVON.

Abstract:Based on the Соколов ЯЕ ejector design method, the geometric parameters of ejectors were determined by the three kinds of selected working condition. Each ejector computational fluid dynamics (CFD) model was established in ANSYS/Fluent .The ejector cycle test model was established in Simulink, based on which the CFD model was used to carry out the simulation under six sets of load currents. Twodimension cubic spline interpolation was used to obtain the twodimension characteristic curve of the ejectors and primary fluid constraints were calculated. Finally, twoejector anode recirculation system was proposed. The simulation results show that the proposed twoejector system can meet the requirement of 0~300 A operating condition with a better circulation effect.

Abstract:In order to explore the feasibility of using binary zeotropic mixtures to replace pure fluids, a subcritical organic Rankine cycle thermodynamic model based on mixtures was established. A screening method of mixtures was proposed on the basis of the boiling point difference. The net power output was selected as the optimization target for the evaporation parameter and mass ratio. For different heat source temperatures, the best mixtures were selected. The system performance parameters and energy loss distribution of the best mixtures and pure fluids are compared. The results show that the net power output of the best mixture is greater than that of the best pure fluid at the same heat source temperature with an increment ranging from 0.13% to 5.04%, which mainly results from mixtures’ smaller latent heat of vaporization and cooling temperature glide closing to cooling water temperature rise. The inlet temperature and pressure of the expander with mixtures are lower than those of pure fluids, and the decrement can reach up to 9.93% and 27.08% respectively. Compared with the best pure fluids, the best mixtures have lower exergy loss in the expander and condenser, which makes the total exergy loss of mixtures lower than that of pure fluids.

Abstract:The paper tries to put forward the application of mathematical analysis to odor tracing research of vehicle components and raw materials. The tracing of odor of vehicle polyvinyl chloride artificial leather was studied with a method based on the rough set theory, the fuzzy mathematics theory and the objective multiattribute weight distribution analysis. The results show that the weight distribution of each attribute is 0.082 3(flame retardant), 0.432(foaming agent), 0.082 7(light stabilizer), 0.221(heat stabilizer) and 0.182(resin). The foaming agent is the primary cause of polyvinyl chloride artificial leather odor. Then the mechanism of odor formation by blowing agents was analyzed by gas chromatographymass spectrometry, which confirmed that the mathematical analysis method based on rough set theory could screen large quantities of data and complete data mining for useful information from the odor intensity value which was subjective and fuzzy. Weight allocation was acquired by introducing the concept of attribute importance, thus the main cause of odor of PVC artificial leather formula was found.

Abstract:Based on a thirdparty platform for evaluating supplier sustainability, transnational companies can effectively monitor how much efforts and improvements their global suppliers have made in sustainability. However, methods on the basis of the platform for evaluating and calculating the weights of indexes and values suffered from a lack of accuracy. A stochastic analytical hierarchy process (SAHP) method and the triangular fuzzy number were adopted to optimize the evaluation model. Besides, a practical case about the sustainability assessment of suppliers was analyzed by the original method and the improved method separately. The comparative results show that the proposed model successfully differentiates the sustainable performance of suppliers and obtains a distinct rank.

Abstract:Combined with a class of actual production decisionmaking needs, a multimode project scheduling problem based on project splitting decision was proposed. In order to minimize the resource investment, an integrated optimization model including project splitting and multimode resource investment model was build. Considering the characteristics of the model, a doublelayer optimization algorithm, including project splitting algorithm and multimode resource investment project scheduling algorithm, was presented. The project splitting algorithm obtained a reasonable resolution scheme by moving jobs among different subprojects and the multimode resourcebased project scheduling algorithm determined the priority rules by analyzing the influence of different jobs on time constraints and resource constraints. The data experiment was carried out by using the Project Scheduling Problem Library(PSPLIB) standard example. Results validated the algorithm.

Abstract:A collaborative design based on building information model (BIM) technology is the orientation of architecture, engineering and construction industry. This paper focuses on the information exchange problems in collaborative design, such as timeliness, completeness and accuracy. Based on the advantages of two kinds of collaborative design methods, such as document linkage and working set of building information model (BIM) technology, and the case study of modular housing design, an analysis is made of the design collaboration technology roadmap, at last, an efficient collaborative model and working characteristics within profession and inter-profession are obtained. From the prospects of software applications and project management, the process framework of BIM multidisciplinary collaborative design is explored, so as to provide a useful method for multi-disciplinary and efficient coordination in the architectural design stage.