Logistics distribution optimization technology for chainassembly manufacturing enterprises

According to the demand on just in time(JIT)distribution of chain assembly manufacturing enterprise, cost optimization of backup storage and distribution betimes were analyzed. A backup storage optimization model was formulated and quantitative analysis of the JIT backup storage optimization technology for the process of logistics distribution was carried out. The optimized distribution technique to realize JIT distribution was studied, and the distribution model of logistics center and the distribution algorithm flow were established. Finally, the proposed models were applied in the planning and construction of a logistics center of an electric appliance set chain enterprise with satisfactory results.     

Deforming mechanisms in a non mandrel drawing process of an aluminum tube from circular to rectangular cross section

An elasto plastic finite element method (FEM) was used to study the deforming mechanisms of an aluminum tube drawn without a mandrel from a circular to a rectangular cross section. The simplified dynamics model and FE model of the non mandrel drawing process were established based on the FEM software deform 3D and simulations subsequently performed. Based on the simulation results, the influence of different semi die angles on the drawing load was summarized, and the proper values were found. As for the blank instability during the drawing process, the tangential stress distribution rule along the rectangle sides was acquired. The drawing die sizing section then was modified with a camber angle of 178° to eliminate instability. The touch boundary and touch stress distribution during drawing process also were analyzed. The aluminum tube produced by the optimized drawing die possesses eligible dimensions and smooth inner surfaces.     

Dynamic Properties of Saturated Clay and Undisturbed Silty Clay

The apparatus for static and dynamic universal triaxial and torsional shear soil testing was employed to perform stress-controlled cyclic torsional shear testing under isotropic consolidated conditions. We conducted a dynamic torsion test of a single hollow sample to obtain its dynamic property data at different effective confining pressures with saturated clay and disturbed silty clay. The results show that the maximum dynamic shear modulus Gmax and ξ obtained from single sample of the cyclic shear test approached those of the traditional method of dynamic torsional testing. We indicate that G/Gmax～ γ andξ/ξmax ～γ of the two soils are independent of confining pressure and testing methods. Each G and ξ can be obtained from the equations we provide. Furthermore, the single sample test method can diminish the differences between the samples during experimentation and effectively provide convenience with authentic experimental results.     

Mechanical Performance of a Vertical Seismic Isolation System Employing a Dish Spring

The base isolation technique has been widely used in different countries to reduce seismic disasters during earthquakes. But most of these devices are effective only in horizontal earthquake responses and do not work well in vertical earthquake responses. We propose a vertical seismic isolation system composed of a dish spring and a visco-elastic damper. To study the stiffness and damping performance of this isolation system, a series of tests under static and dynamic loads were performed. The results show that this system is effective in solving problems related to strong vertical bearing capacity and vertical damping of vertical isolation. The system has not only appropriate vertical stiffness and damper performance, but also excellent mechanical performance. In addition, it is compact, easy to manufacture, and can serve as an ideal vertical damping device.     

Piezoelectric Control of Lifting Surface Flutter

Piezoelectric material was used to establish a single input/single output (SISO) model of a lifting surface with distributed piezoelectric actuators and piezoelectric sensors. The flutter equations and state space equations of piezoelectric laminated structures were also derived. MATLAB, NASTRAN and other software programs compiled by the authors also were used to analyze the flutter and dynamic characteristics. The stability of the closed loop was analyzed for the SISO. The result indicates that the control law can be employed for flutter suppression.     

Energy Consumption Features for Large scale Public Office Buildings in Greater Guangzhou, P. R. China

The annual energy consumption of representative office buildings in Guangzhou, P. R. China, was surveyed over a three year period. Among the modern office buildings surveyed, two large scale office buildings were chosen to analyze the energy consumption features and monthly energy consumption trends. Based on the actual occupied area calculation, the total annual energy consumption of the two office buildings was 149.3 kWh/m2 and 115 kWh/m2, respectively. The air conditioning energy consumption in two office buildings accounted for 49.2% and 38.5% of the total energy consumption. The research results could be used as energy consumption sub databases or references for large scale public buildings in Guangzhou due to the accurate survey technique and representativeness of the survey objects. In addition, energy consumption in these office buildings was compared with levels described in other studies. Energy saving methods are proposed for buildings located in hot summer/warm winter climate zones.     

A 3D Visco elasto plastic Finite Element Analysis of the Asphalt Pavement Rutting Deformation

Based on the dynamic action between vehicles and pavement, a simplified model of vehicle dynamic loading caused by surface evenness was established. This research made it possible to find a Asphalt Pavement Rutting Prediction method based on the theory of visco elasto plasticity which is the basic theory of the dynamics, and finite element method (FEM). Asphalt pavement rutting was calculated and predicted, and the factors influencing rutting were analyzed and calculated. The good agreement between the calculation results and the testing road data indicate that the rutting prediction method is reasonable and reliable.     

Study on Vibration Performance of Engineered Wood Truss Joist Floors

In recent years wood trusses are widely used in buildings due to their excellent performance and ease of construction. As with solid lumber joists, however, the vibration of wood truss joist floors can cause occupants to feel discomfort. To understand the relationship between the vibration performance of wood truss joist floors and the perceptions of occupants, experimental and subjective evaluations were conducted on six truss joist floors. The results show there is close relationship between perceptions of occupants and the fundamental natural frequency, static deflection and vibration acceleration of truss joist floors. The installation of bracings and straps greatly improved the vibration performance of light truss joist floors. We suggest that two or more factors should be included in the design criteria for controlling wood floor vibration, such as static deflection and fundamental natural frequency. Peak acceleration can be adopted as a factor in the evaluation system of vibration performance of wood truss joist floors.     

a multi level fuzzy comprehensive evaluation analytical model of a regional manufacturing information engineering industry

Regional manufacturing information engineering industries are extremely large and complex systems. Based on the implemental integer effect and an evaluation requirement of regional manufacturing information engineering, we analyzed the objectives and characteristics of regional manufacturing information engineering, proposed a multiple evaluation index method of regional manufacturing information engineering. Based on a multiple integration evaluation method, we built a model to evaluate regional manufacturing information engineering. We proposed a measurement model for regional manufacturing information engineering based on multi level fuzzy comprehensive evaluation. Our quantitative research regarding the implementation effectiveness of regional manufacturing information engineering was based on fuzzy quantitative indicators. The model was grounded on collecting indexes of regional manufacturing industry information engineering, and used a fuzzy matrix to normalize the assessment results to a single fuzzy comprehensive evaluation level. Measurement was carried out step by step. Multi level comprehensive evaluation results for a regional manufacturing information engineering industry were obtained. The validity of the model was shown through application practice.     

Detecting a fault line under a single phase to ground of distribution network based on analysis of multi frequency bands

Addressing the problem of choosing a fault line under single phase to ground of distribution network, we presented a new criterion based on analysis of the development of fault line selection and a method using wavelet packets. The feature frequency band, or the combined feature frequency bands of each line, in which the transient capacity current was concentrated was chosen for maximum energy. Based on the principle that the transient capacity current's energy of the fault line was larger than the that of normal lines, fault line selection can be carried out adaptively by contrasting the energy of the transient capacity currents of all lines in each chosen frequency band. The simulation results and spot testing data shows the proposed method can detect the fault line in distribution networks precisely and reliably.