Criteria of strong nearest-cross points and strong best approximation pairs

[EN] The concept of strong nearest-cross point (strong n.c. point) is introduced, which is the generalization of strong uniqueness of best approximation from a single point. The relation connecting to localization is discussed. Some criteria of strong n.c. points are given. The strong best approximation pairs are also studied.The corresponding author Jingshi Xu was supported by the NNSF (No. 60474070) of ChinaPan, W.; Xu, J. (2006). Criteria of strong nearest-cross points and strong best approximation pairs. Applied General Topology. 7(1):41-50. https://doi.org/10.4995/agt.2006.1931SWORD41507

Tris(ethyl­enediamine-κ2 N,N′)cobalt(III) aqua­tris­(oxalato-κ2 O 1,O 2)indate(III)

In the cation of the title compound, [Co(C2H8N2)3][In(C2O4)3(H2O)], the CoIII atom is coordinated by six N atoms from three ethyl­enediamine mol­ecules. The CoIII—N bond lengths lie in the range 1.956 (4)–1.986 (4) Å. In the anion, the InIII atom is seven-coordinated by six O atoms from three oxalate ligands and by a water mol­ecule. The cations and anions are linked by extensive O—H⋯O and N—H⋯O hydrogen bonds, forming a supermolecular network

Permanence and almost periodic solution of a multispecies Lotka-Volterra mutualism system with time varying delays on time scales

In this paper, we consider the almost periodic dynamics of a multispecies Lotka-Volterra mutualism system with time varying delays on time scales. By establishing some dynamic inequalities on time scales, a permanence result for the model is obtained. Furthermore, by means of the almost periodic functional hull theory on time scales and Lyapunov functional, some criteria are obtained for the existence, uniqueness and global attractivity of almost periodic solutions of the model. Our results complement and extend some scientific work in recent years. Finally, an example is given to illustrate the main results.Comment: 31page