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Based on the full analysis of draw-bar box types and functions, and summarizes the occupying larger space question of the box when placed in. Through the studies of the wide application of folding structure in the product, for a particular user, carries on the structure improvement design of rod boxes, not only to retain the existing functions commonly used, while achieving clothing classification, convenient placement, save space; embodies the idea connotation of green design, and highlights the importance of structure design for product innovation design.

Fast-steering mirror system demands higher accuracy and fast responding speed to track targets, but the conventional PID controllers cannot meet the demands. Instead, the fuzzy PID control can greatly improve the capturing and tracking capacities to high-speed dynamic targets. So we apply the fuzzy-PID controller in the positioning loop of the stabilized system, not only improving the transient process of the control system and decreasing the overshoot, but also enhancing the accuracy of tracking stabilization and response. At the end, simulations were performed to test the effectiveness of this method through the MATLAB platform. © (2014) Trans Tech Publications, Switzerland.

The buckle propagation phenomenon in offshore pipelines is an important subject of ocean engineering. The local buckling will easily propagate along the pipeline if the external hydrostatic pressure is high enough. The buckle propagation will seriously hinder the transmission of the oil. This paper focuses on the numerical calculation of buckle propagation pressure using ABAQUS software.

For layout space in the limited land resources and improving the utilization efficiency of urban transportation bridge and traffic conditions, in this paper, according to the request of four lanes of roof, two-way urban light rail traffic in the box, considering the requirements of pipeline layout, water supply and drainage, and fire escape, lighting, ventilated at the same time, based on the existing related specification, give full play to the characteristics of the concrete box girder, preliminarily design out of the single box three rooms inclined web box girder for double-deck traffic of urban bridge, in order to provide the reference design.

Gas emission is basically non-stationary time series, Based on this view, wavelet multi-resolution analysis was applied to the predication of gas emission. Firstly, the gas emission data was decomposed by wavelet multi-resolution analysis. Secondly, the single branch reconstruction of each layer was predicted by establishing AR forecasting model. Synthesized all of the results from every layers, the forecasting result was obtained. The simulation showed that predication for mine gas emission with the method of this paper has much higher accuracy than AR model forecasting model.

A full rang of external prestressing CFRP concrete box girder flexural performance have been tested. Crack distribution, deflection,strain distribution, stress increment of external CFRP have been measured. The results demonstrate that that as the load increase, the shear lag phenomenon on the upper and bottom plate of the box girder is more significantly; There is a certain friction Loss on the interface between CFRP and two steering block which arrange in the mid-span. If suitable element models and material constitutive laws are chose, the ANSYS program may simulate the fully flexural experimental process of the box girder, the result is well agree with the experimental result.

This paper reviews a long-term crude oil markets and trend of dynamic prices during 1986-2011. Based on the hypothesis that crude oil prices dynamics reflect the activity of a competitive market, a jump diffusion model is investigated to examine the empirical performance in a time series. Historical data analysis shows that crude oil prices were characterized by high volatility, high intensity jumps, and strong upward drift, and were concomitant with underlying fundamentals of crude oil markets and world economy. Furthermore, the model forecast that crude oil prices will still have an increasing trend, stay in jump for the next couple of years.

Nonlinear dynamic buckling for sandwich shallow conical shell structure under uniform triangular pulse is investigated. Based on the Reissner’s assumption and Hamiton’s principle, the nonlinear dynamic governing equation of sandwich shallow spherical shells is derived. The corresponding nonlinear dynamic response equations are obtained by Galerkin method and solved by Runge-Kutta method. Budiansky-Roth criterion expressed by displacements of rigid center is employed to determine the critical impact bucking load. The effects of geometric parameters and physical parameters on impact buckling are discussed.

In order to determine the statistical characteristics and distributive regularity of a light commercial vehicle’s braking performance, and further establish corresponding statistical models of vehicle braking performance, large sample testing and statistical analyzing of 220 vehicle’s braking performance are carried out with brake tester bed, as well as 6 braking performance’s optimal fitting distributions and the distributive parameters are obtained also. By means of the statistical characteristics and distributive regularity of the brake performance, the statistical models of the 6 braking performance are established, the model included the probability density function and the distributive function. The calculating results show that in all established models, the largest calculating error absolute value is 6.24%, and the smallest only 0.23%. This research will play an important guiding significance and role to truly evaluating vehicle brake safety performance, improving vehicle brake system design, manufacture, maintenance and repair, as well as revising the relevant limits of vehicle brake safety laws and regulations.

To solve the optimization problem of agricultural transport vehicles’ maintenance cycle, in the premise of periodic testing and diagnosing technical condition of vehicles, based on the Weibull distribution, and use renewal function H (t), the related mathematical model is established, which optimization objective is to make the costs required for vehicle detection, diagnosis and maintenance unit run time (or mileage) the lowest. By analyzing a large number of collected samples, we confirm the running fault of a certain type agricultural transport vehicles belonging to Weibull distribution, and find the optimal solution of built model. Vehicle running tests show that the results are accurate and reliable, can guide the vehicle transport operations.

Using comblike polymer PAALi-g-PEO as matrix, PAALi-g-PEO/LiClO4/LiTi2(PO4)3 polymer electrolyte was prepare by casting. XRD, IR, SEM were used to study the effects of LiTi2(PO4)3 Ultrafine Powder on the conductive properties of polymer electrolyte, and electrochemical impedance spectroscopy was used to test the ionic conductivity of polymer electrolyte. The results show that there is a " competitive complexation" between LiClO4 and LiTi2(PO4)3 with PAALi-g-PEO, which can improve the surface morphology of polymer electrolyte; the conductivity of the polymer electrolyte reaches to a maximum of 4.6 x 10-5S?cm-1, and is improved by 2 to 3 orders of magnitude compared with PEO/lithium salt system.

Six latticed concrete-filled steel tubular (CFST) wind turbine tower K-shape joints were carried on the static load test, which included the weld intersecting joint and gusset plate joint. The failure mechanism and characteristics on the two kinds of K-shape joints, the deformation development process after joints entered plastic stage and the stress state and distribution of joint intersection area were studied. The results show that the failure mode and mechanical behavior of CFST K-shape joints are greatly different from that of the hollow steel tube K-shape joints because of the existence of core concrete, the failure mode of the weld intersecting joints showed the local buckling of compression web member and that of the gusset plate joints presented as the compression buckling and tension tearing of the gusset plates, while the plastic deformation failure of tower column tube wall in joint area was not appear. It is also shown by test results that the stress distribution of tower column tube wall and gusset plate in joint intersection is extremely non-uniform, individual parts already enter plastic state but some other parts are still in elastic state. According to the failure mode and stress distribution conditions of the two kinds of K-shape joints, some design suggestions are drawn, which can provide reference for the latticed CFST wind turbine tower joints.

On the base of appraising synthetically of measuring and testing technique and the monitoring system of thickness, the article analyzed the demand of thickness deviation. It also determined the control core of single chip, and studied on the on-line monitoring system of the wood-based Panel thickness, which is measured by laser sensor and differential transformer sensor and based on the technique of wireless sensors in order to develop monitoring precision and automation standard of blank thickness in wood-based panel industry.

Through a lot of investigations and studies ,and refering to the current related technical specifications and relevant reference, and combining with the characteristics of the ordinary concrete box section component , single box double room concrete huge section box girder which can realize city bridges double traffic is devised creatively,considering of the need of structure and function. By choosing proper element type and material modle, the designed box grider is modeled by the nonlinear analysis software ANSYS. The shear lag effect of the concrete huge section box girder is studied by applying four load conditions including prestressed load, the upper and lower live load and double load. Parameter analysis are done, which include the load type and width-span ratio.And corresponding conclusions are drawn.