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A biodegradable blend foaming material of poly (butylene adipate-co-terephthalate) (PBAT)/poly (propylene carbonate) (PPC) was successfully prepared by chemical foaming agent and screw extrusion method. First, PBAT was modified by bis(tert-butyl dioxy isopropyl) benzene (BIBP) for chain extension, and then the extended PBAT (E-PBAT) was foamed with PPC using a twin (single) screw extruder. By analyzing the properties of the blends, we found that Young's modulus increased from 58.8 MPa of E-PBAT to 244.7 MPa of E-PBAT/PPC50/50. The viscosity of the polymer has a critical influence on the formation of cells. Compared with neat PBAT (N-PBAT), the viscosity of E-PBAT increased by 3396 Pa/s and E-PBAT/PPC 50/50 increased by 8836 Pa/s. Meanwhile, the dynamic mechanical analysis (DMA) results showed that the storage modulus (E') at room temperature increased from 538 MPa to 1650 MPa. The various phase morphologies (“sea-island”, “quasi-co-continuous” and “co-continuous”) and crystallinity of the blends affected the spread velocity of gas and further affected the foaming morphology in E-PBAT/PPC foam. Therefore, through the analysis of phase morphology and foaming mechanism, we concluded that the E-PBAT/PPC70/30 component has both excellent strength and the best foaming performance.

Poly (butylene adipate-co-terephthalate) (PBAT)/thermoplastic starch (TPS) films with additives (maleic anhydride (MA) and titanate coupling agent (TC)) were prepared. The thermal, mechanical, morphological, hydrophobic and biodegradable properties of the films were tested. With the addition of MA and TC, the compatibility and dispersibility of the composite demonstrate enormous improvement, which enhanced the mechanical properties of the films. The tensile strengths of PBAT/TPS films increased from 13.1 to 26.7 MPa in the machine direction (MD) and from 8.3 to 17.2 MPa in the transverse direction (TD). The Young’s modulus increased from 101.5 to 155.6 MPa in MD and from 84.3 to 120.7 MPa in TD. Meanwhile, the biodegradation test showed that the PBAT/TPS films had a higher aging resistance in the presence of MA/TC. These findings gave PBAT/TPS films great applications for designing and manufacturing biodegradation package in life.

Biodegradable poly(propylene carbonate) (PPC)/epoxidized soybean oil (ESO) blends with different component ratios were prepared by melt blending to improve the performance of PPC. The phase morphology, thermal properties, rheological properties and mechanical properties of the blends were investigated in detail. SEM examination revealed good interfacial adhesion between PPC matrix and ESO. According to DSC and DMA, as the content of ESO increased, the glass transition temperature of the PPC component increased, indicating that there was a strong interfacial interaction between the PPC matrix and ESO. The interfacial interaction may be caused by ring-opening reaction between the hydroxyl end groups of PPC and the epoxy groups of ESO, which restricted the chain movement of PPC matrix. The disappearance of the epoxy groups in FTIR indicated that the interfacial interaction between the two phases was due to the ring-opening reaction between PPC and ESO. With the addition of ESO, the thermal stabilities were enhanced. With the increasing ESO content, the modulus gradually decreased. However, the strength at yield, the strength at break and the elongation at break were increased for the PPC/ESO blends, suggesting that the enhancement of the strength and toughness of PPC was achieved by the incorporation of ESO. The rheological measurement revealed that the complex viscosity, storage modulus and loss modulus of PPC were increased with the increasing ESO content at low frequency, which indicated that the addition of ESO enhanced the melt strength of PPC instead of plasticizing PPC.

The accuracy of the rubber constitutive model characterizing experiment data has a crucial influence on the mechanical analysis of rubber structures. In this paper, a new improved hyperelastic constitutive model is proposed, and the model is derived into the stress-strain forms of uniaxial tension, equibiaxial tension and pure shear. Based on the experimental data of filled rubber, the material parameters of each deformation state are obtained by using the newly proposed rubber hyperelastic constitutive model, and the uniaxial tensile (UT), Equibiaxial tension (ET) and Pure shear (PS) specimens are simulated and calculated in the finite element software. the stress state of each finite element specimen is analyzed and the obtained simulation data are compared with the experimental data. It is found that the new model can accurately characterize the hyperelastic mechanical properties of the experimental specimens in different deformation states. At the same time, the reasons for the deviation from the experimental data in the process of plane tensile simulation are analyzed and explained comprehensively. The reliability and accuracy of the classical rubber constitutive relations of polynomial models and eight-chain model are studied. the results show that different hyperelastic models have different ability to describe the hyperelastic behavior in different deformation states. the hyperelastic constitutive model proposed in this paper can be easily embedded into finite element software and has the advantages of accurate results, few material parameters and simple testing.

Shale gas fracturing flowback water (SGFFW) contains a high concentration of colloids and organics which can cause severe water flux decline for membrane distillation (MD). It is desirable to identify the key foulants for MD fouling/wetting for real SGFFW treatment. In this study, coagulation and membrane filtrations with different molecular weight cut-off (MWCO) were applied to try to separate the different fractions of pollutants and evaluate their contributions to MD flux decline. The organics with a molecular weight of 20 kDa, which also belonged to humic acid-like components, protein-like components and fulvic acid-like components removed by coagulation could effectively mitigate MD fouling. However, the rest of the fractions of high molecular weight components of 20 kDa and low molecular weight components (i.e., 200 Da) removed by the UF membrane, had a less significant effect on the water flux of MD. Despite the further removal of small molecular weight compounds and Ca2+/Mg2+ by NF, negligible change for the water flux could be observed, indicating that the rest of the aromatic protein (21.2%) could still cause severe wetting for the MD membrane. In addition, SEM-EDS demonstrated that the combination of organic fouling and crystallization of Ca and Ba contributed to the fouling of the MD membrane. These studies demonstrated that the removal of high molecular weight organics by coagulation and removal of aromatic protein with the molecular weight of 200 Da might be vital for the alleviation of MD fouling or wetting.

In the fields of traffic modeling, objects (i.e., various vehicles) are usually represented using multimodal features. However, two problems remain unsolved on how to utilize these multimodal features better: 1) The missing features because of noise and 2) The curse of dimensionality. In this paper, we addressed these two problems by integrating the multimodal features on the Grassmann manifold. By defining grouping criteria on the multimodal features, the feature vectors are grouped into a set of subspaces, and are further treated as a point on the Grassmann manifold. To deal with the missing features L2-Hausdorff distance, a metric that compares multimodal feature vectors of different number of subspaces, is computed first. And then a kernel matrix is computed. Furthermore, based on the kernel matrix, we proposed a supervised as well as an unsupervised feature selection criterion to obtain t h e representative features on in the Reproducing Kernel Hilbert Space (RKHS). This has alleviated the curse of dimensionality to a significant extent. Experimental results on three different multimodal datasets show that the proposed feature integration technique can outperform the state-of-the-art methods

Multiple person tracking is a very useful task in intelligent video surveillance, which is hindered by many challenges such as the variations of illumination, the irregular changes of human shapes and the particle occlusions. To tackle these challenges, in this paper, we propose a new online learning tracking system to generate the complete trajectory for each tracking object. In detection stage, we build a classifier for each tracking object by online learning in order to provide more accurate detection results. Online learning could real-time update the classifier for an accurately tracking results in the future. In the tracklet generation stage, we apply the spatiotemporal constrain to generate a set of reliable tracklets. Finally, we propose a new Part-based matching method to get the correlation between different tracklets and apply linear programming and greedy algorithm to handle the data association problem to generate the complete trajectory for each tracking object. In particular, our approach is able to cast the multiple cameras tracking problem as a data association problem. The experiments on our proposed method demonstrate state-of-the-art performance in multiple person tracking.

Graphene-based composites now has been payed more and more attention to because it can make up many shortcomings of the pure single-layer graphene.In many papers ,there are one same phenomenon said that graphene can not be well dispersed in matrix since it’s high specific surface area and high surface energy.In this work,we reported the preparation of ZnO/graphene nanocomposites through the way of situ-reaction in the surface of graphite oxide.Then,the nanocomposites were characterized by X-ray diffraction (XRD), Fourier Transform-Infared spectroscopy (FTIR),transmission electron microscopy (TEM), and thermogravimetry (TG). The results indicated that the graphene oxide had been reduced by hydrazine hydrate and the ZnO crystal attached to the surface of graphene well.The ZnO/graphene nanocomposites can be expected to be dispersed in some kinds of rubber to improve their electric and thermal conductivities in the following experiments.

Graphene/NR composite was prepared in emulsion blending and the multilayer graphene was about 4-8 layers. Different mass fraction of this kind of graphene was mixed into NR in this work.The thermal conductivity of this compositive system was respected to be improved apparently since the high thermal conductivity of graphene. In this work, TEM(Transmission electron microscope) was used to observe the structure and morphology of the multilayer graphene. NETZSCH LFA was used to research the change of thermal conductivity with the fraction of grahene changing. DSC(differential scanning calorimetry) was used to research the structure change in the series of composites. The TEM results showed that the graphene we used is 4-5 layers. LFA had proved that the multilayer graphene has affected the thermal conductivity of matrix greatly and DSC also provided evidence to support the same views.

Because Tire not only impact on the handling stability of vehicle but also impact on the ride comfort, it is more practical significant that tire vertical stiffness parameters on handling stability and ride of vehicle impact is considered synthetically than considering handling stability and ride singly. In this paper, full vehicle model was built on the basis of ADAMS/Car. The vertical stiffness of tire was only changed and other parameters remain unchanged, then full vehicle analysis was carried out to get the simulation curves. The impact of the vertical stiffness of tires on the handling and stability and ride comfort was obtained from the curves of simulation. The tires of optimized vertical stiffness can be obtained from the comparison of simulation results. Analytical results can be conductive to designing and producing the tire.

A new experimental apparatus has been developed for measuring the thermal conductivity of liquid by the two transient hot-wire method, which is based on the theory of one-dimensional unsteady heat conduction in infinite medium. The glass tubes, the heating line source and temperature measurement devices are designed in this experiment. As the temperature controller, low-temperature bath provides a constant water bath environment and current calibrator is the power source. Wheatstone bridge is used to test the relation between the temperature changes and resistance. Data acquisition and control unit is data acquisition devices of the Wheatstone bridge. As the temperature coefficient of platinum wire resistance is calibrated. It can be used to measure 32 groups of data from 10°C to 40°C at the every 10°C according to the experimental steps.

Because the brake and turn of automobile is completed by transmitting the force and torque to the ground through the tire, tires can influence the handling and stability of automobile. The impact of the unloaded radius of tire on the handling and stability of automobile was studied on the basis of ADAMS/CAR in this paper. The unloaded radius of tire was only changed and other parameters remain unchanged, then full vehicle analysis was carried out to get the simulation curves. The impact of the unloaded radius of tires on the handling and stability of automobile was obtained from the curve of simulation. The results of simulation are conducive to designing the shape and dimension of tires.

The three-dimensional axial symmetry FEA (finite-element analysis) model is established for 165/70R13 type tire based on ANSYS Workbench FEA software, and numerical simulation at temperature field is implemented, which reflects the temperature distribution at each part of tire intuitively, and has a certain guiding significance of improving tire structure and design.

Rolling resistance can impact on the fuel economy and dynamics of automobile. Numerical simulation can predict the rolling resistance and reduce the experimental cost. So, a simulation model was established base on ANSYS to compute the rolling resistance. Firstly, the 3D model finite element model of a radial tire was setup to solve the strain and stress of a rolling tire. Secondly ,the temperature field of tire was analyzed in line with the analytical result of the strain and stress. Thirdly, the rolling energy loss was calculated to solve the rolling resistance. The simulation method is conducive to the structural design of tire and computation or prediction of the rolling resistance of tire.

Macpherson front suspension model was established by ADAMS/CAR software. The simulation of the parallel wheel traveling and the dynamic analysis of suspension was carried out when the vertical stiffness of tire is 170N/mm and 190N/mm, respectively. Simulation result shows that the enhancement of the vertical stiffness of tire has no influence on the alignment parameters of the front wheel of suspension, but can increase the arm of force of kingpin caste and the stiffness of suspension, decreases the dive, lift and scrub radius, improve the steering returnability and the handling and stability. Analytical result can be used to direct the design of the suspension and tire of automobile.

Thermal conductivity of rubber composites filled with CNTs (carbon nanotubes) and N234 CB (carbon black) were investigated. Result indicated that Thermal conductivity of NR (natural rubber) filled with CNTs is higher than that of NR filled with CB in the case of the same filling amount. CNTs can better improve the performance of thermal conduct of rubber composites than CB. The more the filling content of CNTs is, the higher thermal conductivity of NR composites.

A simulation model is established base on ANSYS software in line with the generating mechanism of the rolling resistance, and then the analytical process of rolling resistance is present. Fourier Series is applied to fit the strain and stress, and order 31 Fourier function is chosen to fit the curves of stress and strain of each element in the rolling course of tire. 2D and 3D finite element model of a 7.00-14 16 PR bias tire is established to solve the strain and stress in a rolling cycle. The rolling resistance of 7.00-14 16 PR bias tire in the case of the rated working condition is simulated and compared with the related empirical equation. The simulation result is basically consistent with that obtained by the empirical equation. The simulation method is conducive to the structural design of tire and computation or prediction of rolling resistance of tire.

The basic and dynamic mechanical properties and thrermal conductivity of rubber composites filled with carbon nanotubes (CNTs) and various particle-sized carbon blacks (CB) were investigated. Results indicated that tear strength and modulus at a definite elongation of rubber composites filled with CNTs were enhanced compared to the conventional CB filler. However, tensile strength and elongation at break became lower. Thermal conductivity of rubber composites partly filled with CNTs is higher than those filled with CB. Rubber filled with the combination of CNTs and the bigger CB particles was beneficial to improve wet-resistant performance and roll resistance of elastomer such as tire.