Advanced Materials Research Vols. 108-111

Abstract: Mathematical model for skeleton stress-strain curve under dynamic loading (SSSC) is one important issue to study the dynamic behavior of soft soil. Based on mechanism of developing process, primary mathematical behavior that SSSC model should meet is analyzed. Mathematical investigation on two conventional SSSC models, namely hyperbolic model and exponential model, is conducted. Dynamic stress index is proposed and employed to signalize the shortcomings of two conventional models. A composite tangent-exponent model for SSSC with three parameters is established, which is a monotone increasing and up limited function. The new model can overcome conventional shortcomings. Finally, good agreement between investigated and new model fitted data has been found out.

Abstract: In this paper, some results on the dividend payments prior to ruin in the classical surplus process with stochastic interest are derived. An integro-differential equation with a boundary conditions satisfied by the expected present value of dividend payments is derived and solved. Furthermore, closed-form expressions for exponential claims are given.

Abstract: In this paper, we study the Gerber-Shiu discounted penalty function. We shall consider the case where the discount interest process and the occurrence of the claims are driven by two distinguished Markov process, respectively. Moreover, in this model we also consider the influence of a premium rate which varies with the level of free reserves. Using backward differential argument, we derive the integral equation satisfied by the expected discounted penalty function via differential argument when interest process in every state is perturbed by standard Wiener process and Poisson process. In some special cases, closed form expression for these quantities are obtained.

Abstract: This paper describes the method of radioactivity measurement to eliminate the outliers in experiment. The value of radon concentration can cause deviation in the process of transmission because the FH-463 is interfered in the process of measurement by external factors such as electromagnetic waves etc. It makes measurements vary greater than the Expectations. And it can only process 10% or less Outlier when using Grubbs’ criterion directly. In order to meet the Radon Concentration for inspection, the paper makes some necessary improvement on the criterion to adapt itself and estimates the sample data with linear regression. The experimental results show that the method is very convenient to reject the data with deviation more effective. The method in this paper can also be used in other fields.

Abstract: Since the 20th century, the environment’s getting worse and has been given more attention to. Many countries have given the laws to protect the environment.In the meantime, the perfect third part reverse logistics can provide the logistics service of all the owner of goods needs, with its profession serving and helping enterprise to enhance labor productivity, reduce cost, develop core competencies. On the other hand, using the third part reverse logistics enterprise is helping a enterprise exaltation the performance also bringing many new risk problems. This paper use the fuzzy comprehensive analysis method to judge the outsourcing risks of reverse logistics. And set forth to builds up a risk factor gathers, adopt the power value factor judgment method to made sure weighting of the evaluation index sign, build up comment gathers, construct and a adjudicated matrix in an experts investigating method, then get fuzzy result of outsourcing risks of reverse logistics by calculating.

Abstract: In this paper, the problem of adaptive stabilization of an underwater navigator with unknown parameters both in the state vector-field and the input vector-field has been considered. By employing the control Lyapunov function method and parameter projection techniques, a direct adaptive controller is designed to complete the globally adaptive stability of the navigator. Simulations are provided to illustrate the effectiveness of our proposed method.

Abstract: The paper uses the multi variable decision tree technology based on rough set to establish a mine effective decision-making model and realize the evaluation of effectiveness for coal mining enterprises. This technology not only effectively reduces the height of the tree, but also takes into account the readability of the classification, thus provides an effective and feasible technical means to the decision-making for enterprise management and improves the management level of coal enterprises.

Abstract: Maintenance is an important part of the product lifecycle management. As important equipment widely used in machine industry, disassembly and maintenance of reducer is crucial. In this paper, according to position and assembly relationship of all parts of reducer in 3D and the basic principles of disassembly, a disassembly relationship matrix was defined. The matrix can well express the disassemblity of the every part in model. Then, a generation algorithm of disassembly sequence was proposed based on and operations. Finally disassembly sequence of reducer was generated in VB.

Abstract: In view of the defect that network DEA (data envelopment analysis) can not establish the model of multi-index synchronously, we proposed multi-index network DEA evaluation method. Cost-type, fixed-type and income-type indices were managed suitably to form inputs and outputs. The linear programming model and its dual model of multi-index network DEA were set up. The correlative definition and theorem of the hybrid model were given. The paper proved that the decision making unit (DMU) being multi-index network DEA efficient is also multi-index DEA efficient when the model doesn’t consider the subsystems, and the subsystems of the DMU are all multi-index DEA efficient synchronously. These results enrich DEA efficient theory further. An example indicated that the hybrid evaluation method can solve multi-index problem efficiently, it can also provide improved information between inefficient DMU and optimum values. The new measure can be a good tool of systems analysis.

Abstract: The Strength Pareto Evolutionary Algorithm (SPEA) is adopted to find time-jerk synthetic optimal trajectory of a hexapod robot in the joint space. In order to get the optimal trajectory, cubic splines are employed and derived under the constraint condition of via points to assure overall continuity of velocity and acceleration. Taken both the execution time and minimax approach of jerk as objectives, and expressed the kinematics constraints as upper bounds on the absolute values of velocity and acceleration, the mathematic model of time-jerk synthetic optimal trajectory planning is built. Finally, SPEA is adopted to optimize the stair-climbing trajectory of a hexapod robot, the simulation results show that this method can solve the trajectory planning problem effectively, and the stair-climbing trajectory can meet the contradictory objective functions of high speed and low robot vibration well.