Abstract:To study the applicability of the forward analysis method based on uniform design under incomplete metrical information, a steel truss is designed and its model parameters are updated. The principal factors of model updating are analyzed and determined on condition that a few of data is measured. The mechanical characteristics of the steel truss joints are simulated by a kind of beam with variable cross-section. The value range of identification results is determined by confidence interval. Three kinds of uniform design program, which are the full-factor program, the nesting program and the multistep program, are used to correct the design parameters of the steel truss. The results show that the model updating factors and their levels determined by above methods are accurate and effective, and the results of model updating by the multistep uniform design program is the most reasonable one. When the mechanical model of a real structure is updated, the factors of model updating should be determined accurately and draw a clear distinction between the primary and the secondary. Multi small-scale uniform design programs should be constructed. And the model should be updated with multistep using these small-scale programs to reduce workloads and avoid irrational model updating solutions. At last, based on the lessons and experiences of the study, a set of methods and its calculation procedure, which are suit for model updating of large complicated structures, are summarized and described.

Abstract:Focus on the problem that the prestressed stress loss due to friction is great, for the reason that the prestressed concrete structures are super long in length and the force is complicated, in the paper, the hybrid reinforcement by both bonded and unbonded strands, the scheme of sectional stretching of the strands and straight bonded strands are proposed to reduce the loss of prestressed stress due to friction. Calculation result shows that the hybrid reinforcement by both bonded and unbonded strands and the scheme of sectional stretching of the strands can reduce prestressed loss, crack width and deflection. In order to determine the area of non-prestressed steel bar and prestressed steel bar, the crack width control method using improved nominal tensile stress is applied. Taking the ratio of prestressed strength as known condition to ensure total reicforcement ratio not exceed the limit. Compression reinforcements are set in compression zones in the ends of beams to meet the requirement relative of the heights equivalent compression zones for taking the dimendions of beams cross sections as constant.

Abstract:To efficiently reduce building energy wasting, and to provide the energy conservation material and good airtightness enclosure to building field, rice-hull mortar is researched and developed as a material for wall. The strength, density, thermal conductivity and freezing resistance are studied by experiments. The rice-hull mortar lightweight composite wall panel is composed by compositing rice-hull mortar, steel bar and rock wool panel, and the fire resistance, and the sound insulation and heat-insulating properties are studied. The experimental result shows that this wall panel has good properties in fire resistance, sound insulation and heat-insulating, it can satisfy the related code for physical and mechanical properties. The design method and structural measures of rice-hull mortar lightweight composite wall panel are put forward, and the economic benefit of the wall panel is analyzed.

Abstract:The aim of this article is to investigate the effect of Fe₂O₃ contents on the characteristics of lightweight aggregate that is made from sewage sludge and river sediment. The physical characteristics, compressive strength, morphological structures and crystalline phases of lightweight aggregate were studied, and the results showed that the lightweight aggregate with higher bulk density, higher apparent density, and lower water absorption could be obtained at Fe₂O₃ contents between 3.5％-7％. The SEM analysis points out that the surface of lightweight aggregate exhibits more vitrification phenomenon as the Fe₂O₃ contents increase, the dense surface of lightweight aggregate with evenly distributed micro porous can be found at Fe₂O₃ contents=5％. The lightweight aggregate with stronger compressive strength (more than 14 MPa) can be obtained when Fe₂O₃ contents are between 3.5％-7％. The XRD analysis implies that the main crystal phase in the lightweight aggregate are quartz, albite-anorthite, kyanite and hematite, and the silicate crystals with stable structure are the main crystal in the internal of lightweight aggregate. As the Fe₂O₃ contents increase, more Fe₂O₃ will transform to hematite with crystal structure. The results indicate that the Fe₂O₃ contents between 3.5％-7％ are appropriate in the process of making lightweight aggregate from sewage sludge and river sediment.

Abstract:The distribution of functional bacteria alone the bio-filter of a up-flow biological aerated CANON reactor was investigated using PCR-DGGE techniques based on the diversity of amoA and 16S rDNA fragments and the identification and phylogeny were performed by molecular clone methods. Besides, the morphology was observed using scan electron microscope (SEM) in this study. The SEM photographs indicated a diverse morphology, of which spherical and elliptical (0.2-1.0 μm) were predominant. The PCR-DGGE results indicated a much better diversity and bigger population of ammonia oxidizing bacteria under a depth of 500 mm, while ANAMMOX bacteria showed a low diversity and the population increased in some degree from top to bottom along the filter. Phylogenetic analysis indicated that Nitrosococcus and Nitrosomonas related ammonia oxidizing bacteria and Candidatus Kuenenia stuttgariensis like ANAMMOX bacteria existed in the reactor. Based on the species traits and the distribution of functional bacteria along the filter, some strategies should be made to improve the partition function and change the filter material, aiming at enhancing nitrogen removal and impact resistance of the reactor.

Abstract:To improve the dewaterability of residual sludge and increase the dosage of flocculant, the residual sludge from one sewage treatment plant was studied by analyzing the impact of combination of microwave pretreatment technology and PAM on the sludge dewawtering. The results showed that proper coupling technique could improve the effect of sludge dewatering considerably compared to PAM. There was significantly decrease in the value of sludge’s tcs, sludge’s water content after centrifugation and sludge’s specific resistance, from 37.3 s,83.68％,1.72×10⁹ s²·g-1 (only by PAM) to 16.7 s,78.16％,0.35×10⁹ s²·g-1, and the dosage of PAM reduced by about 33％. Appropriate combination of microwave and PAM could improve the sludge dewatering significantly.

Abstract:To investigate the influences of pumice chemical surface properties on catalytic ozonation, the decomposition rate of ozone in water was measured over pumice and the mechanism of ozone catalytic decomposition was discussed. The results showed that the pseudo-first order rate of ozone decomposition increased by 37.4 ％ for pumice catalysts. When t-BuOH was added, the rate constant decreased by 45.2 ％ for pumice catalysts, suggesting that the decomposition of ozone followed the mechanism of hydroxyl radical (·OH). The removal of ozone increased with the increasing of surface hydroxyl groups. High initial pH presented a positive effect in the ozone alone and ozone/pumice system. The pumice surface at nearly zero charged point was favorable for the decomposition of ozone in aqueous solution. Ozone aqueous decomposition in the presence of pumice takes place mainly on the natural material surface. The presence of metal oxides in pumice might catalyse ozone decomposition into more active radicals.

Abstract:To discover the kinetic law of ofloxacin oxidation by potassium permanganate in aquatic environment, this article studied the rate constant of reaction and the reaction influencing factors such as potassium permanganate dosage, pH value and temperature. The results showed that the oxidation reaction of ofloxacin by potassium permanganate in aqueous solution followed second-order kinetics. When potassium permanganate was excessive, pseudo-first-order rate and concentration of potassium permanganate followed the equation: Kobs=0.000 092［KMnO₄］-0.002 72. The second-order reaction rate constant was influenced by pH values. The rate of ofloxacin oxidation by potassium permanganate increased with the increasing of temperature, and the reaction activation energy Ea=30.463 3 kJ·mol-1,which revealed that the oxidation reaction between ofloxacin and potassium permanganate was feasible under usual water treatment condition.

Abstract:To explore the effect of different AMF microbial inoculum on the growth of Trifolium repens lawn, we chose two kinds of widely used strains, Glomus mosseae and Glomus intraradices, to study the promoting effect of single bacterium, mixed bacteria on Trifolium repens respectively. The results show that:Simple infliction of Glomus mosseae could obviously improve the infection rate to 53.84％;Trifolium repens has evident dependence on fungicides especially on mixed fungicides. Besides, the dependence of plant aerial parts are obviously higher than underground ones; AMF has apparent promotion on the growth rate of Trifolium repens. The mixed fungicides are better than single ones, the growth rate of plant height, the overground and underground biomass liveweight could be improved by 40.7％, 76.6％, 35.7％ respectively; AMF could effectively enhance the Trifolium repens’ absorption capabilities of nutriment in rhizosphere soil, improve the utilization rate of hydrolysable nitrogen, available phosphorus to 51.6％, 48％. Hydrolysable nitrogen is the main inhibiting factor restraining fungicide's promotion on the growth of Trifolium repens with microbial inoculum, the phosphatic fertilizer is not needed, but a few nitrogen fertilizer is.

Abstract:To explore the COD degradation characteristics of Jiamusi section at Songhua River, water mass tracing and Rhodamine-B tracing were used to investigate the COD model of the normal river flow season and icebound season of Jiamusi section. The corresponding characteristic parameters were identified, the diffusion characteristics of river water quality of the Jiamusi section were discussed, and the validity of the model was verified by the water quality mathematical model and water mass tracing. The results showed that by Rhodamine-B tracing, the transverse diffusion coefficient of the Jiamusi section was 0.41 m²/s, and the longitudinal diffusion coefficient is 43.51 m²/s. The COD attenuation coefficient K(20)=0.188; the COD model parameters were corrected at any temperature K(T)=0.188×1.109 8T-20. The relative error of the measured results and the simulation results were both within 10％, which proved that the COD model and the corresponding parameters were effective.

Abstract:To evaluate the effect of the byproduct of chlorine dioxide—chlorite on human, the neurimotor toxicological effects of sodium chlorite with the concentrations of 0,0 and 360 mg/L on the offspring rats was studied for three generation by using toxicological tests methods, such as muscle power and brain anatomical observation. The results show that no certain toxicological effect and dose-effect relationship in motor neurimotor system associated with chlorite was detected. Cerebellar lesions occurred in several offspring rat. No observed adverse effect was determined as the concentration is 30 mg/L, and the maximum contaminant level of chlorite in drinking water was 1.1 mg/L.

Abstract:Taking the section of Songhua River in Harbin for example in this paper, taking COD as evaluation factors, and using the economic utility model and AHP, the water environmental capacity value has been studied. The results show that, due to water capacity, the saved cost of wastewater treatment is 0.067 billion yuan/year, and the economic benefits is 9.417 billion yuan/year. The total value of the environmental capacity is 9.484 billion yuan/year. The economic benefits of the class II, III and IV are 3.3,4.802 and 11.32 billion yuan respectively. The maximum value of the environmental capacity belongs to the Class III water body, and is about 51％ of the total economic value.

Abstract:To control the regional land development intensity from the environmental protection point of view, proposed method for determining the regional maximum trip generation rate based on environmental air capacity. A part of regional atmospheric capacity calculated by A value method was shared for environmental air capacity. Road network capacity was equivalent conversion to vehicle pollutant emissions. Then adjusted the network traffic volume to let vehicle pollutant emissions was equal to environmental air capacity. After removed transit traffic, used OD matrix estimation theory and adjusted network traffic volume to estimate traffic trips of each traffic zone. According to total traffic trips and available land area, regional maximum trip generation rate was calculated out. A certain region was selected as a numerical example and the result shows that proposed method is effective. Considering environmental air capacity in land development, it helped to protect traffic environment from root cause.

Abstract:In order to improve the highway safety and reduce traffic accidents in the northern region in winter, speed limit of horizontal curve section on ice and snow pavement was studied. Appling theory of vehicle kinematic, and considering drivers’ driving characteristics at the curve of the road, vehicle’s turning characteristic were analyzed on the snow and ice pavement, and the vehicle’s kinematics model on horizontal curve section was established. Freight truck and passenger car were selected as experimental vehicles, and loose snow pavement, compacted snow pavement and ice pavement were selected as experimental pavement. The relation models were established between speed and horizontal curve design index. Selecting three kinds of curve sections with the superelevation value of 6％, 8％ and 10％, vehicle speed-limit control model was solved by Matlab simulation technology, the correlation of speed, circular curve radius and superelevation was analyzed. Safe driving speeds according to different circular curve radius were given on loose snow pavement, compacted snow and ice pavement. It can provide theoretical basis for determining scientific and reasonable speed limit value on highway horizontal curve section under the condition of ice and snow pavement.

Abstract:In order to compare physical and mechanical performance of the cement stable macadam roadbase material between vibration and compaction (static) forming methods, and clarifing reasons of strength difference. Vibration molding was applied for cement stable macadam in test, after curing the physical and mechanical indexes were measure, and comparied with that of the standard compaction (static compaction) specimens. Experiment results show that the relationship of optimum water content and maximum dry density between the vibration molding and standard compaction is inear, the maximum dry density of vibration molding increases 0.04 g/cm³ compare of that of standard compaction, increasing range at around 1.8％. The vibration molding specimens compressive strength increased by 70％ than that static compaction molding overall, 60％ increasing strength comes from skeleton embedded role. Based on the strength equivalent principle, the contant of cement can be saved 2％ to 3％ in cement stable macadam. According to the regression curves of different gradation, the slope of the curve present characterization of adaption for compaction methold, intercept represents the distribution in the aspects of quality in strength. Reseach indicate that for inorganic stabilized aggregate materials, vibration molding’s advantage is not only to improve dry density, but to enhance materials gradation structural effect fully.

Abstract:To improve the applicability of the conflict delay model between left-turn vehicle and straight vehicle in the opposite direction at two-phase intersection, the conflict delay was studied on the basis of M3 distribution. M3 distribution of time headway for straight vehicle is more suitable than negative exponent distribution at signalized intersection. The queue delay of left-turn vehicle and the affect of the number of straight queue vehicles on conflict delay at the beginning of green were considered when M3 distribution was used in this paper. Then a new conflict delay model at two-phase intersection was put forward and it proved effective. The result shows that the conflict delay model improved closely meets with reality and it proved effective. It consummates the theory of existing conflict delay calculation and can provide the theoretical basis for setting up signal phases further.

Abstract:According to load simulator, it is difficult to be accurately modeled. Redundancy torque affects the performance characteristics of load torque seriously. A new method of eliminating redundancy torque is proposed based on a dynamic fuzzy neural network(DFNN). The dynamic fuzzy neural network is the system to be automatic modeling and extracting fuzzy rules of the network, without strong of experts in the field of knowledge. The fuzzy neural network structure changes dynamically. The fuzzy rules form with the learning process. The control strategy is combining with the feed-forward feedback control and direct inverse control, updating algorithm, the network structure and parameters online, tracking of the controlled object inverse model changes. Its parallel the PID controller is to keep the function of the system stability and get a more rapid response and better tracking precision. The satisfactory result of the simulation shows that redundancy torque eliminates effectively, the performance of load simulator system is improved.

Abstract:The elevator group is scheduled by suitable algorithm according to different traffic mode, and the performance of the elevator group control system will be improved. The kernel fuzzy clustering(KFCM) algorithm based on particle swarm optimization(PSO) is proposed to identify the elevator traffic mode. The iterative process based on gradient descent in KFCM algorithm is replaced by PSO algorithm, which has stronger global search capability and local search capability. Meanwhile the sensitivity to initial value of the FCM algorithm is decreased. By using kernel method, the sample in the low-dimensional feature space is mapped into high-dimensional feature space. And the sample feature is optimized and can be linearly divided in high-dimensional feature space so that clustering could be performed efficiently. The elevator traffic flow data collected from some office building is regard as the test sample. The simulation results show that the algorithm proposed has better performance indices compared with FCM algorithm, and the clustering effect of elevator traffic flow is more exact.

Abstract:To achieve energy-saving, optimal dispatching of heat load in heating station with peak-shaving boiler is necessary. First, a dispatch model of integrated optimal energy-saving was built on the combination with the minimum heat energy consumption model and minimum operation cost model, this model can applicable to different heating mode. Then, a immune particle swarm algorithm(IPSO) was used to solve optimal dispatching problems, compared with PSO, this algorithm is not easy to fall into Premature and local extremum, the convergence speed is faster than PSO. An experiment results show the advantages of IPSO, optimal dispatching of heating station with peak-shaving boiler can achieve energy-saving.

Abstract:To improve the electrical properties of CaMnO₃ powders, the modified Ca1-xPr_xMnO₃(0≤x≤0.3) powders were prepared by the sol-gel auto-combustion route at different calcination temperatures and the effects of calcination temperature on the structure and electrical conductivity of the powders were characterized. It was indicated that the resistivity of modified powders represented the typical V type variation of firstly decreased and then increased with the increasing of calcination temperatures, and the resistivity was the lowest when the calcination temperature was at 1 000 ℃. The XRD analysis illustrated that with the increasing of calcination temperatures, the diffraction peaks of Ca1-xPr_xMnO₃ powders were moved to the small angles with the strengthening in intensity. The crystallography data calculated from XRD illustrated that the cell parameters which related to the resistivity of Ca1-xPr_xMnO₃ powders were affected by the calcination temperatures. When the calcination temperature was at 1 000 ℃, the crystal distortion was most distinct. The SEM analysis illustrated that the higher calcination temperature led to the larger size of grains, and the suitable grain size was good at decreasing the resistivity of Ca1-xPr_xMnO₃ powders. Moreover, the quantivalency of Mn was the lowest when the Ca1-xPr_xMnO₃ powders were calcined at 1 000 ℃. The grain boundary, grain size and the quantivalency of Mn together lead to the decreasing then increasing type variation of the resistivity of Ca1-xPr_xMnO₃ powders calcined at different temperatures.

Abstract:To improve the electrochemical performance of Li₂FeSiO₄ with low electric conductivity, the Li₂FeSiO₄/C composite materials were synthesized by a vacuum solid-state method. Compared with Li₂FeSiO₄, the carbon-doping samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and laser scattering technology (LS) respectively. There were no significant changes in the structure and morphology of the products before and after carbon doping, except for slight decrease of particle size and increase of Li₂SiO_3impurity. The results of constant current charge-discharge and capacity intermittent titration technique (CITT) showed that the crystal structure of Li₂FeSiO_4had been rearranged after several charge-discharge cycles (at least 5 cycles). Moreover, the improved Li+ conductive capacity enhanced the electrochemical performance of Li₂FeSiO₄ cathode. However, the effect of carbon-doping based on solid-state reaction on the quality needs to be further improved.

Abstract:To analyze the component and protein heat stability of yak milk fat globule membrane (MFGM), physical method was used to extract and separate MFGM from yak milk fat. The results show that the wash times to separate MFGM is very critical, and the optimum wash time is three. The yak MFGM mainly contains protein (26.93％) and lipids (70.34％), and there are other minor components in MFGM such as hexane, sialic acid and ash. The predominant amino acids in yak MFGM are Glu, Leu, Ser, Lys and Vla, and among these amino acids, the essential amino acids account 49.48％ of total amino acids. When heated to 60 ℃ the MFGM protein, especially for xanthine oxidase (XO) and Periodic acid Schiff 6/7 (PAS6/7), lose markedly. However, the SDS-PAGE under reducing conditions shows that the β-lactoglobulin and α-lactalbumin begin to associate with the MFGM at 60 ℃ the MFGM protein is heat unstable protein.

Abstract:Steel-concrete composite bridge decks with Π shape are widely used in cable-stayed bridges. Due to the bluff body shape, its aerodynamic properties are not as good as stream-line box decks’, and the shape should be optimized to enhance its wind-resistant performance. Based on a 300 m span cable-stayed bridge with Π shaped deck, a series of wind tunnel tests of section model are carried out in TJ-1 ABL wind tunnel, Tongji University. The aim of the tests is to select the best aerodynamic bridge deck shape from the three design shapes. After comparing the flutter and vortex-induced vibration aerodynamic performance of the three bridge deck shapes, some valuable conclusions are gotten. The influence of the bridge deck shape to the flutter aerodynamic performance is different with which to the vortex-induced vibration aerodynamic performance in some cases. By comparing with the results in uniform flow, turbulence flow can effectively reduced the risk and amplitude of the vortex-induced vibration due to the fluctuating components.

Abstract:To improve the seismic performance of new structure with assembly-situ walls, experiment and finite element analysis were applied to 2 models under vertical loads, the stress, cracks, deflection, failure patterns and out-of-plane displacement were studied. Results indicate that the structure shows superior strength and rigidity under normal loads, the out-of-plane instability does not happen but a lag appears as destruction. In addition, the composition between precast shell and cast-in-situ columns shows excellent connection performance and does not slip. The precast shell can significantly improve bearing properties. Meanwhile the “optimal size” section has capability to promote compressive behavior. In conclusion, the new structure is testified to meet reliability requirements; the out-of-plane instability does not appear in normal storey height structures under gravity loads.

Abstract:The influences of elastic bar and three-dimensional revolute joint are considered in the dynamic model to accurately predict the deployment performance of space deployable structure. The clearance joint was simplified by “T” shaped bars and the contact force was adopted by a nonlinear elastic-damper model. The deployment process of a truss unit was simulated with the ideal joint, three-dimensional clearance joint or the elastic bar. A corresponding device was designed, the correctness of theoretical analysis was verified by the experimental result, and the dynamic nonlinear performance of truss was affected. The simulation results show that not only the radial impact contact force, but also the axial contact force exist in the clearance joint, which affect the stability out of the truss plane. Because of the elastic vibration effects of bars, energy transfer occurs, the maximum contact force is reduced, and the number of contacts between the journal and bearing is increased.

Abstract:The elastic-plastic analyses were carried out for 50 moment resisting-chevron braced frames with weak beams for braced frame, in which the brace of out-of-plane slenderness between 30 and 150 and the moment-resisting frames with lateral resistance being respectively 25％ and 50％ of the total base shear are adopted. The results showed that the relative lateral force resisting capacity of the moment-resisting frames and the strength of beam of braced frame are the two key factors for behaviour of the dual lateral force resisting system. The analyses also indicated that the value of overstrength was larger for a dual system with stronger moment-resisting frame and the beam of braced frame. The solutions for the drift ratio of braced frames corresponding to the buckling of the brace in compression and the formations of plastic hinge in the beams of the braced frame and the moment-resisting frames were also derived. The results of these solutions are verified with those using finite element analyses. The study of this paper also shows that the contribution of the moment-resisting frame to the lateral force resistance of the system is limited when the buckling of the compressive brace always occurs; the tensile brace cannot reach its yielding load in the braced frame with weak beam.

Abstract:According to the catastrophe characteristics of the water supply systems when it damaged by emergency, a new vulnerability assessment model was proposed based on catastrophe theory. Taking the earthquake disaster as an example, firstly, according to the damage mechanism of water supply systems under earthquake and the historical earthquake data, the vulnerability assessment indicators was established. Secondly, according to the relationship among the control factors of water supply systems’ functions, the status function and control variables were determined. Thirdly, the cusp catastrophe mathematical model was established, and the normalized formula was derived and the vulnerability classification standard was determined. Then, based on the research results above, the new vulnerability assessment model of water supply systems was proposed. At last, the water supply system of north china was taking as a case study. Through application we could found that the model was theoretical and practical feasibility. It could be used to supply the decision support for the design of water supply systems.

Abstract:To improve the performance of particle filter,ensemble Kalman filter is proposed to construct proposal distribution. And an adaptive fusion model is applied for object tracking. Using ensemble Kalman analysis to build the posterior probability distribution by integrating latest observation information. New particles are resampled from the new proposal distribution. In the tracking process, color model and shape model are fused and updated adaptively. Experimental results show the new proposal distribution can reduce the root mean square error more effectively than traditional particle filter and extended Kalman particle filter. The adaptive fusion model is more stable than single color model. The new proposal and adaptive fusion model can enhance the estimation accuracy and improve the stability of the object tracking.

Abstract:In order to solve the optimal design problem of metropolitan bus transit network, a network optimization model was proposed, which had considered the urban traffic congestion. Firstly it analyzed the malpractices of the shortest path strategy in large cities and reasons of traffic jam. It studied complex network theory and proposed the bypass strategy based on edge betweenness. Through extending the edge betweenness, it defined effectivity edge betweenness and effectivity path. Then it proposed metropolis transit network optimization model based on edge betweenness and designed its algorithm. Take the street network of Changchun City for example to solve. The results show that with the changes of β, the average trip distance first decreases and then increases. When β=0, it is shortest. The average travel speed first is basically stable and then increases sharply. When β=1 the residents average travel time is shortest and the network efficiency is highest. At this time optimization model can rapid decrease the losses of network efficiency caused by traffic congestion.