Advanced Materials Research Vols. 255-260

Abstract: In order to study the short-time traffic flow prediction on high-grade highway, the article proposed a model based on wavelet analysis and RBF neural network. Aiming to the traffic flow’s characteristic of highway, the study focus on three facet: network topology, the difference of continuous flow and discontinuous flow , the flow of lanes’ uplink and downlink are not equal. Thus the article use the wavelet analysis to do data preprocessing, then structure the model of short-term traffic flow prediction based on RBF neural network. The experiment result shows that the new hybrid model adapt to high-grade highway, and model considering traffic flow characteristic is better than the model which is not. Meanwhile the model has the higher precision of prediction.

Abstract: According to the process feature of the coke dry quenching (CDQ), the factors of the destructive mechanism that influence the sequence function properties of the brick were analyzed. The countermeasures have been adopted for the defects of the bricks for CDQ, such as inferior thermal shock stability and short lifetime, etc. In order to search the effect of thermal expansion stress and mechanical load stress on the CDQ, the temperature field and stress field of the flue in the CDQ were analyzed according to the thermal elastic and plastic theory. The Drucker-Prager plasticity model combined with a tension cut-off criterion was described material behavior. All material properties were taken as temperature dependent. The result indicates that the support bracket under high gradient temperature will bring on the highest thermal stress, which is the main reason of fracture of the support bracket. The cycling temperature has the ability to cause repeated crack propagation throughout the whole service period. To solve this problem, the design of the structure, the method of the heat exchange and the properties of the materials will be improved. The obtained results give a good insight into the reasons of material failure and help to find counter-measures for prolonging the lifetime of CDQ.

Abstract: In order to study the influence of the geometry and material properties on the service life of converters, different geometry and material properties of the converters were analyzed by using finite element method in this paper. A mechanical and thermal coupling diagram was introduced to optimize the geometric figure and material properties of the converter by software ABAQUS. The damage of converters was investigated, especially in the lower brick layers of the wall (the bottom wall transition zone). The result indicates both the ladder of the converter with small steps and a proper inclination at the joint between the bottom and wall of converters can reduce the stresses, which make the refractory material damage decrease. The working lining with high conductivity and low thermal expansion will make the thermal stress of the converter lower, which reduces the crack of the converter. The relations between the obtained results and the corresponding lining design and the material properties give a good insight into the reasons of refractory material failure and help to find counter-measures.

Abstract: Under the background of the successively reformation of architecture design course in domestic universities, this paper aims at the teaching regularity of architecture building design courses and the characteristics of students, puts forward a set of effective architecture design teaching process and the reformation method from details, in order to improve the teaching quality and improve the students' comprehensive quality.

Abstract: In order to research and develop a suitable wire rope safety barrier for our country, which will be used as the highway flexible safety barrier for two model demonstrative project of science and technology of Changsha-Xiangtan Highway, the paper presents a new type of wire rope safety barrier, by way of designing the shape of the post, the diameter of the rope, the arrangement and the number of ropes etc., on the basis of the form of structure of the most advanced foreign existing wire rope safety barrier — BRIFEN. The first part is devoted to prove the reliability of the finite element simulation, by comparing the simulation results of the finite element model of BRIFEN with the collision test data, which is published by U.S. Federal Highway Administration. After discussion and analysis, the neotype wire rope safety barrier, which has many posts with C-shaped cross section and 5 ropes, is invented with the post equivalent method. The finite element model of the neotype barrier is established and simulated to determine the dimension of the post. The simulation results achieve the design objective that the maximum dynamic deformation is less than 1.2m when the barrier is impacted by the 10 tons of bus in the speed of 60 kilometers per hour, and provide an important reference for Vehicle Crash Test.

Abstract: Wheeled mobile robot is a typical non-integral system. The non-integral constraints of the system make the dynamics modeling and trajectory tracing more difficult. In the study and development of a wheeled mobile robot prototype SDLG-C, aiming at the characteristics of the non-integral constraints, the dynamics model has been built with the Newton-Euler method by directly integrate the non-integral constraints into the dynamics equations. Consequently, the Obstacle avoidance effects of the high frequency disturbance on the performances of the control system have been eliminated. Based on the behavior–based robot control technology, the intelligent avoiding barriers control system design of an autonomous mobile robot is presented. And the implementation technology of this scheme is introduced; Simulations and experiments are processed to evaluate the proposed algorithm. Both of them have successfully verified the feasibility of the modeling and the effectiveness of the Obstacle avoidance strategy.

Abstract: Using the image feedback system is an effective way to the realize sticking protective film automatically for the screen of mobile phone. System using CCD industrial camera as the testing core, get the image of the film and the screen continuously, and real-time detect the center location of the film and the screen. To accelerate the speed and accuracy of the detection, this design use Sobel’s edge detection algorithm for determining the position of the edge points.

Abstract: The equipment assembled in large steel structure is particular and complex, which must be assembled with a special process plan. Virtual assembly technology provides a feasible idea for equipment assembly. Assembly path planning is the key technology of Virtual assembly. We propose a method of assembly path planning based on the analysis of basic workflow in assembly path planning. Using our algorithm to assemble the equipment find encountered far fewer problems than previous.

Abstract: This paper presents an effort to apply the EKE (extended Kalman estimator) and LSE-UI (least squares estimation for unknown input) technique to detect structures damage with limited output measurements. This technique can be extended to detect structural local damage in complex structures based on substructure approach. Structural parameters and the unknown inputs are identified by a recursive algorithm based on sequential application of the extended Kalman estimator for the extended state vector and the least squares estimation for the unknown inputs. Only a limited number of measured acceleration responses of the benchmark structure subject to unmeasured excitation inputs are utilized. This structural damage detection method is applied to the ASCE SHM benchmark building to test its efficacy and provide a solution to the complex case of the Phase I benchmark problem. Damage detection results indicate that the proposed technique can detect and localize structural damage of the complex benchmark problem with good accuracy.

Abstract: The Bailey method put forward three very significant parameters CA, FAc and FAf, provided an effective way for the asphalt mixture gradation test, and it could evaluate the gradation of asphalt pavement core sample effectively. Based on the analysis of common gradation, the parameters of formula was revised, the application conditions of AC mixture and the parameter range for AC mixture was proposed, that based on the gradation which is standard recommended and the core samples in different pavement conditions. The results proposed theoretical basis for gradation examination correctly with the Bailey method.