Some old and new constructions of the tilde geometry (the flag transitive connected triple cover of the unique generalized quadrangle W(2) of order (2, 2)) are discussed. Using them, we prove some properties of that geometry. In particular, we compute its generating rank, we give an explicit description of its universal projective embedding and we determine its homogeneous embeddings.

Mercury's geological history has been dominated by global contraction caused secular cooling of the planet's interior. This had a profound effect on expression volcanism and tectonism, expressions these two surface evolutionary processes are deeply intertwined. Here, we use case studies from Hokusai quadrangle Mercury to gain insight into interplay between which review throughout this paper. We...

Haifeng Huang1,2, Huajiang Ouyang1,3, Hongli Gao1, Liang Guo1, Dan Li1, Juan Wen1 1 School of Mechanical Engineering, Southwest Jiaotong University, 111 Section One, North Second Ring Road, 610031, Chengdu, China, [email protected] 2 School of Transportation and Logistics, Southwest Jiaotong University, 111 Section One, North Second Ring Road, 610031, Chengdu, China 3 School of Engineeri...

The spider genus Dendrolycosa Doleschall, 1859 was recently revised by Jäger (2011), who described four new species and now comprises 15 known species found from Tanzania to Phillipines and south to New Caledonia (Platnick 2012). Ten of the 15 Dendrolycosa species are known only from females and two only from males. In the present paper, the male of Dendrolycosa cruciata (Roewer, 1955) is descr...