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Based on the contingency theory, this paper uses the panel data of 41 A-share listed companies in China from 2016 to 2019 to convert the product-level data from C-CSI database into enterprise-level data, and then extracts the listed companies involved by using fixed effect model and random effect model respectively. This paper analyzes the impact of information technology investment on customer satisfaction, tests the moderating effect of environmental turbulence and marketing intensity, and carries out a robustness analysis to ensure the reliability of the research results. The results show that: (1) IT investment has a positive impact on customer satisfaction. (2) Environmental turbulence negatively moderates the relationship between the two, but IT investment still positively affects customer satisfaction. (3) Marketing intensity positively adjusts the negative adjustment relationship between IT and CS caused by environmental turbulence. In short, increasing marketing intensity under the condition of environmental turbulence can alleviate the new negative adjustment caused by environmental turbulence. The conclusion of the study provides some experience for enterprises to make IT investment decisions under the current global situation.

For a given frequency response, there exists a lower theoretical limit to the total thickness of a nonmagnetic multilayer absorber. In order to break through the limit, an absorber with multilayer resistive FSS and magnetic absorbing material is proposed. Simulated results show a 19.7% reduction in the total thickness in comparison with the lower theoretical limit of a nonmagnetic absorber by adding a piece of magnetic absorbing material. Then an experimental absorber is fabricated and measured. The measured results show that the magnetic absorbing material makes an improvement on the reflection performance of 7dB at most. Besides, simulations are carried out to analyze the probable causes of the disagreement between the simulated results and the measured results.

With the in-depth deployment of software-defined networks in various business scenarios, controller deployment problem has become a hot issue for software-defined network. At the same time, with the development of the private network of the smart grid, the demand for security, real-time and reliability of the grid transmission service has been continuously improved. In order to solve the problem of wide distribution of power grid system, large amount of data and high delay requirements, we propose an SDN controller deployment scheme based on simulated annealing-genetic hybrid algorithm. This algorithm combines the simulated annealing algorithm and the genetic algorithm. After the simulated annealing algorithm is used to quickly search for a better solution, the positive feedback information is used to narrow down the maximum number of searches and find the optimal path faster. Finally, simulation experiments show that this algorithm can achieve a lower cost controller deployment solution while ensuring the delay between the switch and the controller, and the time required for deployment is shorter.

With the development of modern communication technology, the traditional power grid can no longer meet the needs of massive electricity data collection and processing. Adapting to this change, the Information-Centric Networking is combined with the power communication network. We studied several cache strategies in Information-Centric Networking and then proposed an improved cache scheme based on betweenness and hops. Finally, the improved cache strategy is compared with three other strategies. The simulation results showed that the repetition rate of content traffic is effectively reduced and the performance of power network can be optimized using the improved strategy.

To carry out large-scale teacher training through MOOCs is an important way for teacher professional education in the network age. To make the development of MOOCs more adapt to the characteristics of teachers, we should investigate the teachers' learning pattern in MOOCs. This article uses the teacher professional ability enhancement course "Micro-class Design and Production" as a sample, which is delivered through "iCourse", a platform for Chinese higher education elaborate open courses. Through the analysis of the typical learning data within the course, i.e., the registration rate and the completion rate of the students, the utilization of the learning resources and the interactive behavior on the course discussion board, the author found the behavioral characteristics and patterns of the teachers demonstrated through their learning in the MOOC. In the paper, the authors also proposed corresponding suggestions for the improvement of curriculum development quality.

With the continuous digitalization and informationization in power communication network, the demands of processing, storage, and forwarding large amounts of power data are increasing. Adapting to this change, the software defined network, which has high flexibility and programmability, is combined with the power communication network and changed the traditional network architecture. This paper studies in the routing mechanism based on SDN and proposes a genetic ant colony (GAC) routing algorithm, which combines the advantages of genetic algorithm and ant colony algorithm. After getting several preferable solutions produced by rapid search in large scale network, GAC algorithm makes full use of positive feedback to narrow the maximum search times, and then finds the optimal path quickly. Finally, after comparing the GAC routing algorithm with two smart routing strategies, the simulation results show that the speed of the algorithm is improved as well as the efficiency, so that the performance of power communication network can be optimized using the GAC routing algorithm.

Composites are widely used in aviation, aerospace and other fields because of their high specific strength, high specific stiffness and easy molding. However, in the process of using the concentrated stress, heavy shocks may form different degrees of damage. Especially, the internal delamination will reduce the stability and safety of the structure. Based on the analysis of damage location and damage degree, the size of delamination of composite is studied. The Explicit module of ABAQUS software is used to carry out finite element simulation to obtain the propagation signals of different delamination sizes. A model of between signal and delamination size is established based on support vector machines. It is proved that this method can precisely identify the size of the delamination.

In this paper, the scattering principium and the two-dimensional distribution of Bragg lobes are discussed. Based on theoretical calculation, how to avoid Bragg lobes in principal plane by tilting the antenna aperture is researched. In order to verify the correctness of the theoretical analysis, monostatic RCS of a 20×20 array with different tilting angles are simulated. A good agreement between theoretical analysis and simulation can be observed. The simulated results show that appropriate tilting angle has an obviously effect on the RCS reduction.

In order to solve the enormous pressure of the stereo video surveillance mass data storage and transmission, the human visual system(HVS) is introduced into the stereo video compressing coding by researchers, but the perception mechanism of inter-view and the inherent characteristics of monitoring the scene are neglected, hence the coding efficiency is affected. Therefore, this paper puts forward the surveillance-oriented binocular stereo video attention model for video coding. Firstly, the paper analyzes the binocular competition perception mechanism of stereo video, then, it builds up an attention model of binocular stereo video coding framework, lastly, it is applied perception rate allocation. It is expected that in the case of the same subjective quality, this research can reduce 20% of the coding bitrates to meet the professional needs of video surveillance system from 2D to stereo upgrade and updating.

In this paper, the method of splitting plane wave finite-difference time-domain (SP-FDTD) algorithm is presented for the initiation of plane wave sources in symplectic finite-difference time-domain (SFDTD) scheme. By splitting the fields on one-dimensional (1D) grid and using the nature of numerical plane wave in FDTD, an efficient plane wave sources is simulated on 1D grid, and a perfect match is achieved for a plane wave propagating at any angle forming an integer grid cell ratio. Numerical examples show the valid of the proposed method.

Most of the 3D's data acquisition for buildings is a huge project, while the existing 2D data has not been fully exploited. This paper puts forward a method based on the existing 2D vector data to construct the simulated 3D map service. The key technique is to introduce the city 2D building's attribute “height” as elevation data, then based on the elevation data and the 2D geometric data, the simple 3D model can be constructed. After that, using the projection transformation and shear transformation to convert the simple 3D models to 2D data which have 3D visualization effect. Finally drawing the processed building data in 2D plane to achieve the 3D viewing effect. The proposed method is rapid flexible simplify and enhances people's sense of geospatial cognition.

Combining the character of landscape and the theory of Markov chain, this paper inferred the forecast model of fuzzy weight Markov chain. The new model which was called FWMC to predict the future value of cultivated land demand in land use planning. Factors to consider in driving conditions was used in this model, the real response to landscape pattern change position using a weighted Markov transfer based on prior forecast model. This developed the predictable method of Markov chain and widened the practice range. Finally, the rate of change of landscaper cover was simulated by using existing data. The author applied GIS technology and mathematics model to calculate the change of Jiangsu' landscape for many years. The results provided the scientific basis for the development of sustainable economy. And these showed that the new method was more scientific and practical than traditional predictive models.

Multi-factor of regional social relates to the landscape pattern, Model can simulate the drive mechanism can result by computer simulation . This paper inferred the forecast model of fuzzy weight Markov chain. The new model which is called FWMC to predict the future, combining the character of landscape and the theory of Markov chain, value of cultivated land demand in land use planning. Factors to consider in driving conditions is used in this model, the real response to landscape pattern change position using a weighted Markov transfer based on prior forecast model . This developed the predictable method of Markov chain and widened the practice range . Finally, by using existing data to simulate the rate of change of landscape cover. Changes in landscape structure simulation predicted The author applies GIS technology and mathematics model to calculate the change of Jiangsu’ landscape for many years. The results provided the scientific basis for the development of sustainable economy. And show that the new method is more scientific and practical than traditional predictive models.

The flow distribution property of gas-solid two-phase in Y-Shaped branch pipe was expatiated. The pneumatic conveying experiments for millet and micro-glass bead with density 1340 kg/m3 and 2510kg/m3, average particle diameter 2mm were carried out at horizontal Y-shaped branch pipe which were designed with one branch being unchanged (keeping 15°) and the other being changeable (the angle values are 5°, 10°, 15°, 20°, 25°, 30° respectively ). The flow distribution property was expressed by the ratio of the solid mass flowing in the changeable branch vs. the total mass of solid.

Image segmentation plays an important role in both qualitative and quantitative analysis of medical ultrasound images. Recently cluster ensemble techniques have been shown to be effective in image segmentation, but selecting ensemble approaches to combine multiple clusterers is critical problem in image segmentation with cluster ensemble. In this paper a new ensemble approach with the spectral graph theory is proposed. Specifically, base clusterers are obtained by K-means cluster algorithm firstly. Secondly, the similarities matrix is constructed based on results of base clusterers. Thirdly, the image is segmented using cluster ensemble approach which integrates K-means clusters using improved spectral cluster algorithm based on the similarities matrix. Experimental results show that the proposed method performs better than some existing cluster ensemble techniques without high computational cost.