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Your search keyword '"Zhang, Dehai"' showing total 2 results
Start Over Author "Zhang, Dehai" Topic differential equations Publication Year Range Last 10 years
2 results on '"Zhang, Dehai"'

1. An improved gray prediction model for China’s beef consumption forecasting.

Author

Zeng, Bo, Li, Shuliang, Meng, Wei, and Zhang, Dehai

Subjects
BEEF industry, PREDICTION models, SUPPLY & demand, FOOD consumption, GOVERNMENT policy, ANIMAL products, VECTOR error-correction models
Abstract

To balance the supply and demand in China's beef market, beef consumption must be scientifically and effectively forecasted. Beef consumption is affected by many factors and is characterized by gray uncertainty. Therefore, gray theory can be used to forecast the beef consumption, In this paper, the structural defects and unreasonable parameter design of the traditional gray model are analyzed. Then, a new gray model termed, EGM(1,1,r), is built, and the modeling conditions and error checking methods of EGM(1,1,r) are studied. Then, EGM(1,1,r) is used to simulate and forecast China’s beef consumption. The results show that both the simulation and prediction precisions of the new model are better than those of other gray models. Finally, the new model is used to forecast China’s beef consumption for the period from 2019–2025. The findings will serve as an important reference for the Chinese government in formulating policies to ensure the balance between the supply and demand for Chinese beef. [ABSTRACT FROM AUTHOR]

Published
2019
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2. A novel triangular boundary crack front element for 3D crack problems based on 8-node serendipity element.

Author

Xie, Guizhong, Zhou, Fenglin, Zhang, Dehai, Wen, Xiaoyu, and Li, Hao

Subjects
*BOUNDARY element methods, *DIFFERENTIAL equations, *ASYMPTOTIC distribution
Abstract

This paper developed a novel 6-node triangular boundary crack front element for 3D crack problems. The developed element method was constructed based on an 8-node serendipity element and a distance function that defines the distance from arbitrary point inside the element to the crack front. The specially constructed shape function captures the square-root asymptotic behavior of the distribution of the displacement nearby the crack front. In order to employ the crack front element in the dual boundary element method, conversion from conforming triangular crack front elements to non-conforming triangular ones was performed through a matrix transformation. In the implementation of dual boundary element method, a displacement extrapolation method is adopted to compute the stress intensity factor at the crack front. Finally, three examples were presented to verify the efficiency of our proposed crack front element. In all the numerical examples, the presented crack front element exhibits high accuracy and efficiency in the examples. [ABSTRACT FROM AUTHOR]

Published
2019
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