Advanced Materials Research Vol. 421

Abstract: In this article, the reliabilities of the electrical system and the fire control system of certain-type armored vehicle are studied based on the Copula function. First, the margin distribution is confirmed by the Weibull distribution, and then the Archimedes Frank Copula function is solved and validated, and finally, the reliability function and the failure rate of the system are obtained.

Abstract: Taking on the features of agility, intelligence, Internet and socialization in the wake of rapid expansion of global manufacture and cutthroat competition, to establish an e-intelligence maintenance system is crucial for manufacturing enterprise to reduce costs and increase profits in the global market. Based on the analysis of requirement for e-intelligence maintenance in manufacturing industry of our country, this paper puts forward a total solution to e- intelligence maintenance system. Moreover, it expounds in particular the system realizing technology, viz R&D methods and process to set up a framework based on .NET Framework. The key realizing technology is including grid-based computing model, system prototyping development, and development of personalized maintenance service kit.

Abstract: In order to the effects of structural sizes of a hyperbolic on its performance, sensitivity and accuracy analysis are performed in this paper. According to the structure feature and force exerted on the flexible hinge, the closed-form equations are formulated for compliances to characterize both the active rotation and all other in- and out-of-plane parasitic motions by using the Castigliano’s second theorem. Meanwhile, the accuracy equations are obtained using the Castigliano’s second theorem. According to the closed-form flexibility formulas, the effects of the four structural parameters, such as thickness, notch depth, length and width, on the flexibility of flexible hinge are analyzed, respectively. In order to study further the effects of the structural parameters on its flexibility, we derive the sensitivity equations, and the sensitivity analysis is carried out. Meanwhile, the accuracy analysis of the hyperbolic flexure hinge is performed. The analysis results have shown that the parameters have large influence on in-plane compliance, and have small effects on out-of-plane one. And the changes are larger within initial small range of parameters, while be small variation in larger size range. And the length has no effect of sensitivity.

Abstract: A three dimensional geometric model of a homemade selective laser sintering (SLS) system is simplified and imported into Ansys Finite Element Software for static and modal analysis. The analysis results show that the supporting base that holds up the laser system undergoes large deformations. The machining accuracy can hardly meet the high-precision requirements of sintered parts with complex internal and external geometries. A method is put forward for the structural optimization of the SLS system. The calculation results show that the bending deformation of the supporting base decreases by 73.2%, and the maximum stress also decreases significantly. It indicates that the high precision manufacturing can be achieved with the improved SLS system.

Abstract: A novel predictive control strategy is applied to dynamic supply chain management under networked manufacturing. The optimisation-based control scheme aims at a complete management framework for production-inventory systems that is based on model predictive control (MPC) and on a neural network time series forecasting model. The model proves to be very useful in production-inventory systems that is enough to keep production and inventory balance. A move suppression term that penalises the rate of change in the transported quantities through the network increases the system’s robustness. The results show that the proposed scheme can improve significantly the performance of the production-inventory system, due to the fact that more accurate predictions are provided to the formulation of the MPC optimization problem in real time.

Abstract: In an era of knowledge economy, building an internal knowledge baseis is one of basic conditions to improve competitiveness and to develop sustainablely for modern companies . In this paper, we develop a complete information dynamic game model on this problem and analyze the strategic behavior of the risk averse participators to find out the subgame perfect Nash equilibrium from perspective of individual employees. We also offer some managerial recommendations on how to balance individual interest and collective interests in modern companies. At last, a series of corresponding management enlightenments are given out based on the above analysis.

Abstract: The scale and complexity of search space are important factors deciding the solving difficulty of an optimization problem. The information of solution space may lead searching to optimal solutions. Based on this, an algorithm for combinatorial optimization is proposed. This algorithm makes use of the good solutions found by intelligent algorithms, contracts the search space and partitions it into one or several optimal regions by backbones of combinatorial optimization solutions. And optimization of small-scale problems is carried out in optimal regions. Statistical analysis is not necessary before or through the solving process in this algorithm, and solution information is used to estimate the landscape of search space, which enhances the speed of solving and solution quality. The algorithm breaks a new path for solving combinatorial optimization problems, and the results of experiments also testify its efficiency.

Abstract: Two graphs are introduced to describe the precedence and cluster constraints among stamping operations, i.e., operation precedence graph and operation adjacency graph. A graph colouring algorithm clusters the operations based on both the precedence and adjacency graphs to form joint operations. A joint operation matrix is then generated. A matrix based algorithm is presented to iteratively order the joint operations to generate the final sequence according to the index of priority for each operation. The algorithm is implemented in C++ and is fully integrated with SolidWorks CAD system. A case study is presented to illustrate the algorithm.

Abstract: It is an issue in the application of Non-Uniform Rational B-Spline (NURBS) how to achieve the characteristic parameters based on a given curve. In this work, the parameterization method of accumulated chord length is used to construct the knot vector. The tangent vector is chosen as the boundary condition. The characteristic parameters including the control points, the knot vector and the weights are calculated according to the key points and corresponding weights of a given curve. An example of NURBS interpolation for cranium is given based on a selective laser sintering (SLS) machine. The characteristic parameters are obtained with Rhino software. The NURBS interpolation for cranium is realized using these characteristic parameters in the SLS machine. The results show that the practical sintering curve is coincident with the given curve.

Abstract: We study the effect of force convection and temperature on the double dendrite growth during the solidification of binary alloy using a phase-field model. The mass and momentum conservation equations are solved using the Simple algorithm, and the thermal governing equation is numerically solved using an alternating implicit finite difference method. The results indicate that dendritic grows unsymmetrically under a forced flow, the growth velocity of the upstream tip is faster than the downstream tip. The downstream tip of the first dendrite and the upstream tip of the second dendrite are influenced each other, the upstream tip of the second dendrite will Coarsen, and the concentration at the boundary between them is the highest. Moreover, the interaction between the two dendrites is more and more obvious with the increasing of the temperature.