Vitrimers are a novel generation of spacecraft materials. However, how to improve the atomic oxygen (AO) resistance of vitrimers remains un-explored, although it is critical for extending the lifetime of spacecraft at low earth orbit. Herein, we fabricate a series of AO resistance epoxy...

We examine the rounding phenomenon (called <i>window dressing</i>) in financial reporting of U.S. high-tech and low-tech firms. By requiring that investments in research and development be expensed as incurred, the generally accepted accounting principles provide low-tech firms with a larger set of...

Irrigation districts in Inner Mongolia face problems that are familiar to irrigation areas around the world: shortage of water resources, poor management of water, inefficient use of water resources, and imbalance of financial revenues and expenditures. Water user associations have been promoted...

The conic model proposed by Davidon (1980) [Davidon, WC (1980). Conic approximations and collinear scalings for optimizers. SIAM Journal on Numerical Analysis, 17, 268–281.] is an extension of quadratic model incorporating more information than quadratic model. In this paper, we propose a...