The finite element method (FEM) plays a valuable role in computer modeling and is beneficial to the mechanicaldesign of various structural parts. However, the elements produced by conventional FEM are easily inaccurat...The finite element method (FEM) plays a valuable role in computer modeling and is beneficial to the mechanicaldesign of various structural parts. However, the elements produced by conventional FEM are easily inaccurate andunstable when applied. Therefore, developing new elements within the framework of the generalized variationalprinciple is of great significance. In this paper, an 8-node plane hybrid finite element with 15 parameters (PHQ8-15β) is developed for structural mechanics problems based on the Hellinger-Reissner variational principle.According to the design principle of Pian, 15 unknown parameters are adopted in the selection of stress modes toavoid the zero energy modes.Meanwhile, the stress functions within each element satisfy both the equilibrium andthe compatibility relations of plane stress problems. Subsequently, numerical examples are presented to illustrate theeffectiveness and robustness of the proposed finite element. Numerical results show that various common lockingbehaviors of plane elements can be overcome. The PH-Q8-15β element has excellent performance in all benchmarkproblems, especially for structures with varying cross sections. Furthermore, in bending problems, the reasonablemesh shape of the new element for curved edge structures is analyzed in detail, which can be a useful means toimprove numerical accuracy.展开更多
The Tumor, Node, Metastasis(TNM) staging system,adopted by the Union for International Cancer Control(UICC) and the American Joint Committee on Cancer(AJCC), has been recently revised, with the new 8^(th) edition of t...The Tumor, Node, Metastasis(TNM) staging system,adopted by the Union for International Cancer Control(UICC) and the American Joint Committee on Cancer(AJCC), has been recently revised, with the new 8^(th) edition of the staging manual being published in January 2017. This edition has few but important evidencebased changes to the TNM staging system used for lung cancer. Radiologists should be aware of the updated classification system to accurately provide staging information to oncologists and oncosurgeons. In this article, we discuss the rationale, illustrate the changes with relevance to Radiology, and review the clinical implications of the 8^(th) edition of the UICC/AJCC TNM staging system with regards to lung cancer.展开更多
基金the National Natural Science Foundation of China(No.11572210).
文摘The finite element method (FEM) plays a valuable role in computer modeling and is beneficial to the mechanicaldesign of various structural parts. However, the elements produced by conventional FEM are easily inaccurate andunstable when applied. Therefore, developing new elements within the framework of the generalized variationalprinciple is of great significance. In this paper, an 8-node plane hybrid finite element with 15 parameters (PHQ8-15β) is developed for structural mechanics problems based on the Hellinger-Reissner variational principle.According to the design principle of Pian, 15 unknown parameters are adopted in the selection of stress modes toavoid the zero energy modes.Meanwhile, the stress functions within each element satisfy both the equilibrium andthe compatibility relations of plane stress problems. Subsequently, numerical examples are presented to illustrate theeffectiveness and robustness of the proposed finite element. Numerical results show that various common lockingbehaviors of plane elements can be overcome. The PH-Q8-15β element has excellent performance in all benchmarkproblems, especially for structures with varying cross sections. Furthermore, in bending problems, the reasonablemesh shape of the new element for curved edge structures is analyzed in detail, which can be a useful means toimprove numerical accuracy.
文摘The Tumor, Node, Metastasis(TNM) staging system,adopted by the Union for International Cancer Control(UICC) and the American Joint Committee on Cancer(AJCC), has been recently revised, with the new 8^(th) edition of the staging manual being published in January 2017. This edition has few but important evidencebased changes to the TNM staging system used for lung cancer. Radiologists should be aware of the updated classification system to accurately provide staging information to oncologists and oncosurgeons. In this article, we discuss the rationale, illustrate the changes with relevance to Radiology, and review the clinical implications of the 8^(th) edition of the UICC/AJCC TNM staging system with regards to lung cancer.
