Abstract: The purpose of this paper was to generate several possible configurations of micro/nano-positioning stage with bridge-type mechanism based on graph theory. The structural characteristics of stage were discussed first. Then, these modules made up of micro/nano-positioning stage were abstracted. Thus the stage could be described with a tree-graph. According to the spanning tree theory, several possible configurations of stage are enumerated correspondingly. Subsequently, the configuration synthesis of six bridge-type mechanisms was investigated and 720 results were obtained. Rules for generating structures with symmetry are established. On the basis of this, several innovative structures are presented. Furthermore, the result of this paper provides a practicable approach for the structural design of stage and the design method based on graph theory is effective.
Abstract: An increasing number of manufacturing enterprises commence to adopt flexible assembly line to meet the demands of the rapidly changing market. RFID technology is employed to collect the real-time production information in workshop and overcome difficulty to identify key production objects. In this paper, based on the RFID tag data model of smart objects, an RFID application solution on flexible assembly line is proposed, and an RFID-enabled manufacturing executing system is designed, which is integrated with the RFID-enabled real-time data capture system for flexible assembly line. In addition, the framework and integrated operation mode of corresponding RFID-enabled MES are established. The results of application in a motorcycle assembly line show obvious improvement in both production efficiency and quality.
Abstract: This paper introduces the Granger causality test to the analysis of the relationship between coastal ports and port cities manufacturing technology economy in China, verifying the role of coastal ports in promoting the port city economy not having yet been full. The development of Chinese coastal ports efficiency since 2000 to 2009 is analyzed through Data Envelopment Analysis (DEA), which can be concluded that the technical efficiency reached low in the decade. Especially after 2004 most of the coastal ports were inefficient, and most of the inefficiency, which increased in the size, came from pure technical and scale inefficiency. On this basis, this paper analyzes the problems of the present port construction in China, and puts forward the countermeasures of its harmonious development.
Abstract: Based on the scattering theory of elastic waves, employing the wave function expansion method, the scattering and the dynamic stresses concentration of SH wave by circular tunnel with lining are investigated. The analytical solution of the problem is derived, and the numerical solution of the dynamic stress concentration factors around the lining is presented. The effects of the shear elasticity of the surrounding rock and the lining, the wave number on the dynamic stress concentration factors are analyzed. Analysis has shown that the shear elasticity of the surrounding rock and the wave number are factors that influence dynamic stress concentration factor, and provide important theoretical foundation for the earthquake evaluation of lining.
Abstract: Supplier selection is a critical and demanding task for companies that participate in B2B manufacturing e-commerce. In this paper, we propose anintegrated analytic hierarchy process- data envelopment analysis (AHP-DEA) for multiple criteria supplier selection. The proposed AHP–DEA methodology uses the AHP to determine the weights of criteria, the dataenvelopment analysis (DEA) method to determine the values of the linguistic terms. A numerical example demonstrates the application of the proposed method.
Abstract: Load distribution of the flexspline under alternating dynamic loads is complicated, and it’s difficult to measure the stress of the flexspline by experiment. To study the intensity of the flexspline, operating process of a harmonic drive is simulated based on the contact theory and the explicit algorithm of the finite element method. The parameterized finite element grid of the whole harmonic drive model is realized by Matlab, and then the assembly process of the vave generator is simulated by ABAQUS. Meanwhile, the distribution of the flexspline stress and the load characteristics of the flexspline tooth during dynamic transmission process of a harmonic drive are analyzed. The fatigue fracture position on the flexspline is forecasted according to the simulation results at last.
Abstract: In this paper, built mathematical model on Flow Shop scheduling, put forward a RNA genetic algorithm based on DNA computing to solve the Flow Shop scheduling problems. Adopt RNA four digit system encoding method based on DNA computing and RNA computing operator in genetic algorithm. It resolved the encoding scheme and convergence problem which exists in the conventional genetic algorithm. Under some constraint conditions, this genetic algorithm got simulated. Simulation results showed that this algorithm has a better optimum searching and seeking abilities, made the scheduling results comparatively reasonable and expanded the application of DNA computing.
Abstract: Continuous casting process is a traditional and widely-used technique in producing the cathode of electric lead. In this paer, soft-sensors based on a support vector regression （SVR, in short）model and an artificial neural networks （ANNs, in short）model respectively, were presented for the estimation of the lead slices thickness in the process.Experiments had been performed on the continuous casting machine to obtain the data used for training and testing of the soft-sensors. For the continuous casting process, the soft-sensors proposed here represents a viable and inexpensive on-line sensors.The study results indicate that a good prediction accuracy of the slice thickess can be provided by the soft-sensors, and even a better performance can be achieved by using pre-processing procedures to the input data, it also shows that the SVR model is an attractive alternative to ANNs model for the soft-sensors, when the number of samples is relatively small.
Abstract: Taking Yangshan sea-area of the Qiqu archipelago as an example, a 2D numerical model of tidal currents is established to study the change of the current field and the influence of branch blocking in different stages of northern port construction, including tide process, velocity and tidal prism, in the main channel waters and the branches. Verifications with the observed data indicate that the simulated results can reflect the current fields in the region. Based on the numerical model it is rechecked and researched the influence of branch blocking in different stages of northern port construction on the changing processes of hydrodynamic, including tide process, velocity and tidal prism, in the main channel waters and the branches. The paper is to provide the scientific basis for the construction of Yangshan Port’s subsequent engineering.