Advanced Materials Research Vols. 317-319

Abstract: The multi-tension loading in the optimized tensile split Hopkinson bar tests for pure copper sheets was used to investigating growth and coalescence of drilled voids in pure copper sheets, recorded by a high-speed camera. The results of scanning electron microscopical investigation of the microvoid evolution in recovered pure copper sheets showed void coalescence mechanisms which are similar to that of visualized drilled voids. The semi-empirical relation [8] for void shape evolution under quasi-static tension was compared with our computed results revealing the dynamic and clustering effects on void growth. The possibility of application of Thomason model[9] and Considere’s condition[10] for void coalescence to thermoviscoplatic constitutive model was explored under impact tension. The main effects affecting dynamic growth and coalescence of voids were presented including the geometry (void size, shape, orientation, spacing), the material properties (dynamic constitutive model) and the stress state (impact tension condition).

Abstract: In virtue of fuzzy matrix and fuzzy linear transformation, not only the fuzzy comprehensive ability’s quantitative value is got, but also single fuzzy ability’s quantitative value is got. The type of software personnel can be distinguished by comparing the fuzzy integrated ability assessing value of software personnel with pre-set threshold, pointed out statistic improvement for project in the process of confirming factors, in order to enhancing the accuracy of the estimate results. And an analysis of specific application instance of improved COCOMO model verified the validity of the improved model.

Abstract: In this paper, the flexible modeling capabilities of ANSYS and the excellent nonlinear solving ability of ABAQUS were multiplied for simulating the deep 3D-excavation. The results illustrated that both advantages of two numerical analysis softwares were combined. The complex stresses and deformations of the deep 3D-excavation were exactly simulated. The approximate solutions show that this method could analyze the coupling effects between the soils and the walls of the 3D-excavation. It was a successful application of using advanced CAE technologies into geotechnical engineering.

Abstract: A steel mill uses four functionally identical heavy vehicles manufactured by two different manufacturers. The information of failure time and downtime is available. This paper aims to compare the field reliability of the vehicles based on the field repair reports. A cost model is developed to comprehensively evaluate the overall performance of the vehicle. The preventive maintenance frequency of the vehicle is determined based on an empirical approach. The study is useful for the manufacturer to have a clear picture on the competability of its product and is also useful for the user to select an appropriate model of vehicles.

Abstract: Focusing on the requirements of safety and reliability of fuze setback arming device of rocket-assisted projectile, a zigzag groove setback device with two degree of freedom was designed with Inventor 6. The dynamic simulation is developed under environment of VisualNastran. The optimum parameters of up inertia-cylinder mass, down inertia-cylinder mass, up inertia-spring rigidity and down inertia-spring rigidity were tested by orthogonal method and simulated. The results indicate that this setback device can effectively differentiate setback overload in launch and impact overload at service handling; credible arming time of fuze is about 128ms when the even overload of the rocket engine is 100g; the optimum mass of up inertia-cylinder and down inertia-cylinder are respectively 3.19g and 1.41g, the optimum rigidity of up inertia-spring and down inertia-spring are respectively 32.7 N/m and 21.8 N/m.

Abstract: This paper investigates the network security problem which is complex to evaluate. The key of this evaluation is to establish the factors and weights. Traditional methodologies cannot get rid of the key issues, resulting incorrect evaluation. In order to improve the accuracy, this paper proposes an evaluation model which is based on analytical hierarchy process (AHP) to evaluate the network security in the real-life background. There are several steps. First, evaluation factors are set up through Delphi method. Second, the weights are determined by AHP. Third, the evaluation is executed. Finally, the real-life cases are used to verify the model. The verification indicates that AHP enables to evaluate the network security efficiently in terms of objectiveness, high accuracy and comprehensiveness.

Abstract: With the development of the simulative theory and calculation method of drainage pipe network, urban drainage pipe network model gradually become an indispensable part of the urban drainage system management. The characteristics of modern drainage pipelines,the content of drainage pipelines system model, the problems of combining GIS with drainage pipelines and how to solve them are briefly described in this paper.

Abstract: When the idea of service has redefined the way that a warehouse is operated and facilitated the emergence of public warehouse as a new logistic mode, in recent years, the maturity of RFID technology and its applications have brought deeply impact to the warehouse once again. In this paper, a conceptual framework about how to use RFID in the public warehouse is proposed. The main functions of the framework, working flow of a public warehouse and its management style of are illustrated. At last, some key enabling technologies are described in detail, that is, RFID tag and reader configuration, task pool model and task implementation mathod.

Abstract: The electronic or pneumatic multi-section and multi-probe gauges are widely used for diameter and coaxiality measurements due to their high measurement efficiency in workshops. However, their measurement accuracy is determined mainly by the manufacturing errors of the assembly coaxiality master, therefore, how to establish coaxiality measurement datum reference is the key technology. The physical coaxiality masters are expected to be the impossible "zero error datum reference". The higher manufacturing accuracy of the masters, the more expensive for their manufacturing costs. A novel mathematical method on the basis of error separation principle was proposed in order to separate the manufacturing errors of the master. The basic principle is that the eccentric error of the coaxiality master can be expressed as the first harmonic function and the ideal zero-error datum reference could be established by the mathematical method of two sampling operations in phase difference of 180° in coaxiality master for gauge initialization. This method can be called as "mathematical datum reference" for coaxiality measurement. Experimental results indicate that the coaxiality measurement results of the multi-section and multi-probe gauge by the novel mathematical method coincide with those of the three-coordinate measuring machine and the maximum difference of both is about 0.0014 mm. The new coaxiality measurement principle can separate the datum error of the coaxiality master theoretically and can improve the coaxiality measurement accuracy greatly with the common accuracy coaxiality master.

Abstract: The paper presents a contactless mobile payment method based on security TF card and NFC technology, with which we can use the security TF card, instead of a special SIM card that support SWP protocol, as a security module to store the user’s important information (e.g. transaction data) in mobile payment. And because security TF card can be distributed by non-telecom operators, the method can obtain a more extensive support by units and institutions other than telecom operators. then it is meaningful to the development of NFC technology.