Research on QoS Testing Methods of Virtual-Real Mixed Networks

Lizhen Zhao

Abstract: Based on the actual needs of network QoS testing in network engineering, a typical network topology was designed. Using network simulators, virtual machines, and real physical networks, a virtual real hybrid tested network topology was constructed. Combined with NTP network time protocol, Cisco SLA protocol, and ICS and routing technology in Win10 system, a tested network environment with virtual real mutual access was simulated and constructed. On this basis, different types of data streams in actual networks were simulated to detect the main performance parameters of network operation, and verifies a low-cost network QoS testing method.

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Research on the construction and application methods of course knowledge graph in online course teaching platform environment

Mingyu Zhao

Abstract: With the rapid development of artificial intelligence technology, knowledge graph technology has received widespread attention in various fields. The use of educational knowledge graph technology to promote curriculum and teaching reform has become an important research direction for the development of digital and smart education in education. The article constructed course knowledge graph in ChaoXing online course platform environment to explore the construction mode and application methods. The course knowledge graph indexes and analyzes teaching resources and learning behavior data based on knowledge points, providing students with an autonomous learning environment and learning path planning ability, and teachers with teaching data management and evaluation methods based on knowledge points, which helps to improve the quality of online course teaching and resource construction.

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A high-order entropy stable finite volume scheme for shallow water equations over bottom topography

Xiangpeng Meng, Zhonghua Yao, Rendi Liu, Shouguo Qian, Gang Li

Abstract: This article develops a high-order accurate, entropy-stable finite volume scheme for the shallow water equations over non-flat bottom topography. First, we construct a second-order accurate, well-balanced, semi-discrete entropy-conservative scheme, which satisfies the entropy identity for the given entropy pair and maintains the still-water steady states exactly. The key idea is to ensure that both the discretization of the flux gradient and the source term match each other. Second, affordable entropy-conservative fluxes for the second-order entropy-conservative schemes are critical for the ultimate high-order scheme. A high-order, well-balanced, semi-discrete entropy-conservative scheme is then achieved by using the second-order entropy-conservative schemes as a building block. Third, the high-order accurate, well-balanced, semi-discrete entropy-stable schemes are proposed by adding a suitable dissipation term to the existing entropy-conservative scheme. This is done using a weighted essentially non-oscillatory reconstruction of the scaled entropy variables to suppress the numerical oscillations of the entropy-conservative scheme. Finally, the semi-discrete scheme is integrated in time using the Runge-Kutta method to achieve the final scheme. Extensive numerical results strongly indicate that the proposed scheme satisfies the discrete entropy inequality, is well-balanced, maintains high-order accuracy for smooth solutions, and can capture small perturbations near the steady state.

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