Band 3, Heft 2

A characterization of the equilibrium of information flow networks and the dynamics of network formation are studied under the premise of local information flow. The main result of this paper is that it gives the dynamic formation procedure in the local information flow network. The research shows that core-periphery structure is the most representative equilibrium network in the case of the local information flow without information decay whatever the cost of information is homogeneous or heterogeneous. If the profits and link costs of local information flow networks with information decay are homogeneous empty network and complete network are typical equilibrium networks, which are related to the costs of linking.

This paper tests the inflation hedging ability of four categories of important financial assets in China: Commodity futures, real estate, gold and industry stock and select the assets that have significant inflation hedging effect. Then the authors construct the mean-variance model under the inflation factor, using the selected assets to construct the inflation hedging portfolio, solving the model and obtain the optimal investment strategy with inflation protection function. The result shows that the portfolio constructed by the model have more stable real returns and its inflation hedging ability can be even better if the short selling restriction of stocks is eliminated.

The cost of materials is the largest proportion of a construction project’s total budget. If the materials cannot be delivered to the construction site on time, completely and with acceptable quality, the project’s duration and cost will be greatly affected. Based on the generalized project risk element transmission theory and system dynamics, a system dynamics model was developed to capture dynamics of procurement risk elements transmission during construction projects and how various procurement risk elements affect the project’s duration and cost by simulation. In this paper, procurement risk element is considered as the uncertain factors in procurement. Based on these results, it is concluded that the developed model can provide important information for risk managers and project managers addressing procurement risk.

Scientific and technological talent has become one of the key elements to accelerate economic development all over the world. The internal mechanism of the promoting of economic growth by scientific and technological talent gathering has been analyzed using mathematical modeling methods based on two regional cases. Further the conclusion has been extended to multi-location application. The scientific and technological talent gathering index has been introduced in the application. The data used was accessed from China Population Statistics Yearbook, Science and Technology of China Statistical Yearbook and China Statistical Yearbook. The regional concentration index of scientific and technological talent in different regions has been calculated based on the data. Findings of the research affirmed the positive correlation between scientific and technological talent gathering and regional economic growth. Finally recommendations to promote regional scientific and technological talent aggregation have been proposed.

Based on singularly perturbed bilinear quadratic problems, this paper proposes to decompose the full-order system into two subsystems of a slow-time and fast-time scale. Utilizing the fixed point iterative algorithm to solve cross-coupled algebraic Riccati equations, equilibrium strategies of the two subsystems can be obtained, and further the composite strategy of the original full-order system. It was proved that such a composite strategy formed an o ( ε ) (near) Stackelberg equilibrium, and a numerical result of the algorithm was presented in the end.

In this paper, a new approach to rolling bearing diagnosis is proposed, which applied orthogonal matching pursuit with pulse atoms. Solving orthogonal matching pursuit with pulse atoms (OMP_PA) is an NP-hard problem. With the help of multi-population genetic algorithm, better solution is obtained, and the shortcoming of sensitiveness to parameters setting in genetic algorithm is improved. According to the comparisons with other algorithms, OMP_PA could precisely extract the pulse components, and the interferential components are almost filtered. The experiments show that, OMP_PA could determine the fault location of bearings, and clearly displayed the vibration model. In conclusion, it provides a new way to the diagnosis for bearings.

Several observations in real economic systems have shown the evidence of non-Gaussianity behavior, and one of mathematical models to describe these behaviors is Poisson noise. In this paper, stationary probability density of a nonlinear business cycle model under Poisson white noise excitation has been studied analytically. By using the stochastic averaged method, the approximate stationary probability density of the averaged generalized FPK equations are obtained analytically. The results show that the economic system occurs jump and bifurcation when there is a Poisson impulse existing in the periodic economic system. Furthermore, the numerical solutions are presented to show the effectiveness of the obtained analytical solutions.

Conventional GM(1,1) model shows some limitations which affect directly to the model applicability as well as prediction accuracy. In order to improve the disadvantages existing in the original grey model, the authors analyze the translation transformation approach to optimize the raw sequence for grey modeling. This paper mainly carries on the proof of the existence of translation transformation from the perspective of smooth ratio and gives the method to solve the best step size of translation transformation. Then, the authors applied the grey models optimized by translation transformation to analyze the problem of the consumption of rural residents in China. As a result, the authors find GM(1,1) model optimized by translation transformation has characteristics of higher accuracy and simple calculation process and an important practical application in residents consumption.