Applied Mechanics and Materials Vols. 84-85

Abstract: According to the application, structural features and technical requirements of 320/50t-22m large quenching crane, the bridge girder of crane were optimized. Vertical stiffness of the main beam and frame stiffness were mainly calculated, moreover, track subsidence caused by the main beam’s torsion and the fatigue stress of the main beam were checked. A guideline and reference for the future design of similar cranes were provided, thus the paper has some application value.

Abstract: Inner flow field numerical simulation model of conical nozzle was established. The relationship between conical nozzle structural parameters and its performance were obtained with simulation research. Simulation results show that the maximum outlet velocity of conical nozzle and the fluctuation range of radial velocity at outlet are determined by its convergence angle α and slenderness ratio C_p. With the increasing of α, the maximum outlet velocity of nozzle is increased at first and then reduced. When α is small, the fluctuation range of radial velocity at outlet is minute. When α is big, the fluctuation range of radial velocity at outlet is dramatic. With the increasing of C_p, the maximum outlet velocity of nozzle is increased at first and then reduced. When C_p is small, the fluctuation range of radial velocity at outlet is obvious. When C_p is big, the fluctuation range of radial velocity at outlet is minute. The optimal structural parameters of the nozzle are α = 40°, C_p =30°. Experiments of conical nozzle performance with different α were carried out. Experimental results show that ejection range of water jet is maximal when α = 40°.

Abstract: The present solutions of well cementing are mostly designed by designers’ experience and calculation which can not predict the engineering quality after application of the designs. Meanwhile some questions in the designs can not be solved before construction. On the basis of detailed evaluation of every influential factor according to construction and environmental conditions, this article provides cementing fuzzy neural network model by means of 2nsoftEditor neural network modeling tools, and the stable software systems with the combination of artificial neural network and fuzzy logic rules are expected to improve the credibility of cementing quality prediction. Construction practice shows that cementing quality prediction with application of fuzzy neural network system before cementing can greatly reduce the cementing costs and improve the cementing success ratio.

Abstract: With the increase request of strip quality, the roller eccentricity has become the important factor of influencing product quality. On the practical model of Cold-rolling Mill of 300, this paper establishes eccentricity compensation control practice of Cold-rolling Mill of 300 which applies wavelet transform method. Based on mufti-resolution decomposition of roll force signal by use of wavelets, eccentricity signals are separated from disturbances and noise,and self-optimization is employed to real-time control the roller eccentricity. The results show that the method is effective.

Abstract: Tungsten carbide (WC) is often induction welded to tougher and economical material, such as martensitic type 420 stainless steels (SS 420), to form a hybrid cutting tool stock. However, undesired softening in the SS 420 next to the fusion interface usually occurs. This softening is due to localized carbide precipitation in SS 420 matrix arising from heating during the induction brazing process. The aim of the present work is to investigate the soft zone of the SS 420 weldment by controlling the heat input during induction brazing. The result showed that cooling rate has a great effect on softening of the SS 420 weldment during induction brazing.

Abstract: There were a lot of common points in turning the slender trapezoidal thread and the triangular thread on the common lathe, but there were also respective special features, because the trapezoidal thread used in machinery's transmission spot, the accuracy requirement was high, and during the machining, it was more complicated to turn the slender trapezoidal thread on the common lathe than the triangular thread. As long as control its processing rule, and adopts the correct processing method, we definitely may machine the high accuracy thread, this article elaborates ways and means of machining trapezoidal thread on slender axis, the machining of the trapezoidal thread for the slender axle can provide the experience and reference basis for such parts in the future. Introduction

Abstract: The development of the various scanning probe microscopy techniques has revolutionized the study of surface structure up to atomic scale. Among these techniques, Nanoeducator as scanning force microscope or SFM has been developed to allow the accomplishment of various measuring techniques both for scanning tunneling microscope (STM) and non-contact atomic force microscope (AFM). However, there is no exact guidance how to fabricate cantilever to gather the good image. In order to achieve the better cantilever for students, this paper emphasizes on tip’s processing by altering etching length parameter as tip plays an important role to achieve better quality image during scanning operation. This paper also provides a guide for undergraduate student to know better about this machine as well as the principle behind it for them to acquire better quality image for their works. It was found that the number of turning of tungsten and etching time could produce good tip of cantilever. It is recommended for lecturers, students and technician to consider about turning and time of etching to produce a better tip of cantilever in Nanoeducator.

Abstract: A new finite element simulation model based on two trochoidal tool-paths was constructed, and was used to simulate a full immersed milling with three flutes cutter. In this FEM model, the special method used here is to construct two trochoidal curves at the beginning with an offset value which is just equal to the feed value per tooth. These two linked trochoidal curves represent tool paths generated by two flutes respectively so as to construct the workpiece model. Cutting forces in the feed direction and in the normal direction were analyzed in detail. A verifying experiment shows this simulation is credible in general. This method can also be applied into situations of milling with more flutes such as face milling.

Abstract: Potential knowledge useful for traffic management optimization is hidden in a huge amount of data. Previous works use the prior data pattern labels to train the artificial neural network to attain the intelligent data mining models. The performance of the models suffers from the experts’ experience. To relieve the impact of the human factor, a new hybrid intelligent data mining model is proposed in this work based on self-organizing map (SOM) and support vector machine (SVM). The SOM was firstly used to capture the clustering information of the database through an unsupervised manner. Then the identified samples were treated as input to train the SVM. To optimize the SVM model, the particle swarm optimization (PSO) algorithm was employed to tune the SVM parameters and hence the satisfactory SVM data mining model was obtained. 2000 practical data sets from the Intelligent Transportation Systems (ITS) were applied to the validation of the proposed mining model. The analysis results show that the proposed method can extract the underlying rules of the testing data and can predict the future traffic state with the accuracy beyond 97%. Hence, the new SOM-PSO-SVM data mining model can provide practical application for the ITS.

Abstract: Based on the RFID (Radio Frequency Identification Devices), this paper presents new research work of signal timing intersection in the aspects of the key points of design, the main parameter and timing methods. Finally, the intersection of signal timing of fuzzy control method based on RFID is proposed through comparative analysis of the intersection of several traditional signal timing methods.