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This paper discusses the optimization problem of improved error back propagation（BP） algorithm for mathematics teaching quality evaluation. K-means clustering is used to collect data for teaching quality assessment, and the clustering center of samples is determined. The weight and threshold of mathematics teaching quality evaluation index are determined to optimize the teaching quality evaluation. MATLAB simulation results show that under the error conditions of 0.1, 0.01 and 0.001, the accuracy and efficiency of the improved BP algorithm for teaching quality evaluation are better than the standard BP algorithm, which is basically consistent with the expected teaching quality objectives. Therefore, the improved BP algorithm can accurately evaluate the teaching quality and reduce the influence of other factors on the teaching quality evaluation results. [ABSTRACT FROM AUTHOR]

Fuzzy analytic hierarchy process has been widely used in many fields, but Thomas L. Saaty, the architect of AHP, questioned the validity of fuzzy AHP and had published three articles which show the invalidity of using fuzziness with the AHP. In this paper, we review Saaty's comments on fuzzy AHP from three aspects: fuzzy AHP is lack of mathematical validity; the judgments in AHP are themselves already fuzzy and fuzzy them again has no meaning; improving inconsistency need not improve the validity of the outcome. Through this paper, we do further analysis on both AHP and fuzzy. We hope it will make some help for decision-makers when using AHP. [ABSTRACT FROM AUTHOR]

The paper studies the optimal production and order policies with deteriorating items for a two-echelon supply chain system consisted of one manufacturer and one retailer. In a finite planning horizon, manufacturer adopts make-to-order policy to satisfy the demand of retailer. The learning effects in production and order processes are considered. A mathematical model is established for this two-echelon supply chain system. The objective is to decide the optimal decision variables, including the optimal production quantities, the optimal number of order and the optimal order time so as to minimize the total cost of the system. Via analyzing the cost structure of the system, this paper proves the existence and uniqueness of the optimal policy by using the technique of relaxing order times to continuous variable, and proposes the method to solve the optimal policy. Finally, the paper presents a numerical example to illustrate the applications of theoretical results. [ABSTRACT FROM AUTHOR]

Based on the knowledge of electrocardiology, electrophysiology and related subjects, this paper introduces some important methods for analyzing ECG of arrhythmias or difficult ECGs combining with author's clinical experience of many years. These methods embrace understanding arrhythmias with concepts such as refractory period, reentry and decremental conduction, identifying ventricular tachycardia using depolarized vector, and analyzing arrhythmias by mathematical methods. Grasping and using these methods can be very helpful for analyzing and understanding ECGs as well as improving the diagnostic level of difficult ECGs. [ABSTRACT FROM AUTHOR]

In this paper, the implicit Runge-Kutta Scheme is derived to solve the NS equations, and its characters of stability, precision and efficiency are studied respectively. Some benchmark cases are calculated to validate the capabilities of the numerical program. The results show that the implicit R-K method given in this paper has high stability, high precision and high efficiency, which make it suitable to compute the unsteady reactive nonequilibrium flow. [ABSTRACT FROM AUTHOR]

Based on analysis of previous studies of topological relations between spatial objects, this paper reviews the research contents and methods for describing relations between certain spatial objects, and for topological relations between uncertain spatial objects. Potential research problems in topological relations between spatial objects are discussed. [ABSTRACT FROM AUTHOR]

In the process of multiple attribute evaluation using traditional multi-attribute decision method, some problems such as that the evaluation results are close to each other, the evaluation values differ to each other scarcely, the difference between these evaluations is not obvious and so on can easily occur in practice. Although the multiple attribute decision model based on maximizing deviation can enlarge the evaluation values discrepancy for the optimizing and ranking of the decision making schemes, it only considers the variable weight caused by the discrepancy of the attribute values and neglects the weight of the evaluation indicator itself in practice, causing that the evaluation results easily deviate the actual results. In view of this, the paper makes further amendments to the multi-attribute decision making model based on maximizing deviation. After considering the weighted weight and the weight of the evaluation attribute completely, the author designs an improved maximizing deviation decision making model and applies the model to the comprehensive effectiveness evaluation of the multi-mission planning of near space system, which can provide decision support for the selection and optimization of the multi-mission planning schemes of near space system. Finally, the model is proved to have certain applicability by the case analysis. [ABSTRACT FROM AUTHOR]

In this paper, a two-stage method of transit hub location optimization is proposed. Firstly, alternative hub locations are determined by evaluating the attractiveness of each alternative location. The attractiveness of alternative location can be obtained by three aspects: the accessibility, the aggregation of transit lines and the layout of transit lines. Based on the alternative hub location set, considering the benefit of passenger and operator, a multi-objective model is presented to design transit hub location in a city. Then, a multi-objective genetic algorithm is also developed to solve the model. Finally, the data of Dalian city is used to validate the two-stage method for transit hub location optimization. The results show that the chosen alternative locations are almost cover main land use of Dalian city by using the attractiveness-based model. This indicates that the attractiveness-based model is a feasible and efficient way to determine alternative hub locations. Furthermore, the solution of the transit hub location optimization accords with the actual conditions of Dalian city. This indicates that the proposed multi-objective model and algorithm can consider the quantity, location and cost of transit hubs. [ABSTRACT FROM AUTHOR]