四、城市地面(The floor of the city) 圣玛可广场就象世界上所有的城市空间一样,有着优美的铺砌,它们经过精心设计,使步行成为美的感受。脚下的地坪对步行者来说,是非常直接的个人感受,但不幸的是,现代城市建设者已经忘记了走过地面可...四、城市地面(The floor of the city) 圣玛可广场就象世界上所有的城市空间一样,有着优美的铺砌,它们经过精心设计,使步行成为美的感受。脚下的地坪对步行者来说,是非常直接的个人感受,但不幸的是,现代城市建设者已经忘记了走过地面可能得到的视觉和触觉质量。城市地坪可以铺砌图案,有质感,有色彩,如同一张富丽的地毯。此外,地面铺砌材料强烈地影响其适用性、舒适感和美观。铺砌的质感能引导步行者的活动力和行动,甚至使他们的流向渠化;防止他们进入某些特定地段,或使他们速度放慢。光滑的地面材料鼓励人走,而粗糙的地面则抑制人行走;虽然走路的人中未必总有穿尖细跟高跟鞋的女士,但是,即使穿平跟鞋走在粗糙的地面上也得放慢速度。展开更多
The paper provides an interpretation of Leibniz＇s account of space that extends beyond the predominant interpretations in terms of the relativity of space, and the latter is mainly understood through the differential...The paper provides an interpretation of Leibniz＇s account of space that extends beyond the predominant interpretations in terms of the relativity of space, and the latter is mainly understood through the differential perspective of each monad＇s extrinsic denominators. This is attained by a thorough explication of the principle of indiscernibles, the abolition of the principle of locality, the advanced conception ofentelecheia in late Leibniz, and the character of the perception of each monad, which allow to discover in Leibniz＇s idea of space the notion of the hologram, and the holographic interconnectedness of things in the Universe.展开更多
Let G be a p-group (p odd prime) and let X = Cay(G, S) be a 4-valent connected Cayley graph. It is shown that if G has nilpotent class 2, then the automorphism group Ant(X) of X is isomorphic to the semidirect product...Let G be a p-group (p odd prime) and let X = Cay(G, S) be a 4-valent connected Cayley graph. It is shown that if G has nilpotent class 2, then the automorphism group Ant(X) of X is isomorphic to the semidirect product GR x Ant(G,S), where GR is the right regular representation of G and Aut(G,S) is the subgroup of the automorphism group Aut(G) of G which fixes S setwise. However the result is not true if G has nilpotent class 3 and this paper provides a counterexample.展开更多
Restricted edge connectivity of a graph G is defined to be the minimum size |U| of a set U of edges such that G-U is disconnected and G-U contains no trivial component K1. The high order edge connectivity Ni, i1, is t...Restricted edge connectivity of a graph G is defined to be the minimum size |U| of a set U of edges such that G-U is disconnected and G-U contains no trivial component K1. The high order edge connectivity Ni, i1, is the number of edge outsets of size i. TO determine all Ni, i 1, for a general graph is NP-hard. In this paper, the authors evaluated the restricted edge connectivity and the high order edge connectivity Ni, 1 i -1, for any connected Abelian Cayley graphs explicitly.展开更多
We investigate here various kinds of semi-product subgroups of Poincar6 group in the scheme of Cohen-Glashow＇s very special relativity along the deformation approach by Gibbons- Gomis-Pope. For each proper Poincar6 s...We investigate here various kinds of semi-product subgroups of Poincar6 group in the scheme of Cohen-Glashow＇s very special relativity along the deformation approach by Gibbons- Gomis-Pope. For each proper Poincar6 subgroup which is a semi-product of proper lorentz group with the spacetime translation group T（4）, we investigate all possible deformations and obtain all the possible natural representations inherited from the 5 - d representation of Poincar6 group. We find from the obtained natural representation that rotation operation may have additional accompanied scale transformation when the original Lorentz subgroup is deformed and the boost operation gets the additional accompanied scale transformation in all the deformation cases. The additional accompanied scale transformation has a strong constrain on the possible invariant metric function of the corresponding geometry and the field theories in the spacetime with the corresponding geometry.展开更多
The second Poincard kinematical group serves as one of new ones in addition to the known possible kinematics. The geometries with the second Poincard symmetry is presented and their properties are analyzed. On the geo...The second Poincard kinematical group serves as one of new ones in addition to the known possible kinematics. The geometries with the second Poincard symmetry is presented and their properties are analyzed. On the geometries, the new mechanics based on the principle of relativity with two universal constants （c, l） can be established.展开更多
文摘四、城市地面(The floor of the city) 圣玛可广场就象世界上所有的城市空间一样,有着优美的铺砌,它们经过精心设计,使步行成为美的感受。脚下的地坪对步行者来说,是非常直接的个人感受,但不幸的是,现代城市建设者已经忘记了走过地面可能得到的视觉和触觉质量。城市地坪可以铺砌图案,有质感,有色彩,如同一张富丽的地毯。此外,地面铺砌材料强烈地影响其适用性、舒适感和美观。铺砌的质感能引导步行者的活动力和行动,甚至使他们的流向渠化;防止他们进入某些特定地段,或使他们速度放慢。光滑的地面材料鼓励人走,而粗糙的地面则抑制人行走;虽然走路的人中未必总有穿尖细跟高跟鞋的女士,但是,即使穿平跟鞋走在粗糙的地面上也得放慢速度。
文摘The paper provides an interpretation of Leibniz＇s account of space that extends beyond the predominant interpretations in terms of the relativity of space, and the latter is mainly understood through the differential perspective of each monad＇s extrinsic denominators. This is attained by a thorough explication of the principle of indiscernibles, the abolition of the principle of locality, the advanced conception ofentelecheia in late Leibniz, and the character of the perception of each monad, which allow to discover in Leibniz＇s idea of space the notion of the hologram, and the holographic interconnectedness of things in the Universe.
基金the National Natural Science Foundation of China (No.10071002) andCom2MaC-KOSEF.
文摘Let G be a p-group (p odd prime) and let X = Cay(G, S) be a 4-valent connected Cayley graph. It is shown that if G has nilpotent class 2, then the automorphism group Ant(X) of X is isomorphic to the semidirect product GR x Ant(G,S), where GR is the right regular representation of G and Aut(G,S) is the subgroup of the automorphism group Aut(G) of G which fixes S setwise. However the result is not true if G has nilpotent class 3 and this paper provides a counterexample.
文摘Restricted edge connectivity of a graph G is defined to be the minimum size |U| of a set U of edges such that G-U is disconnected and G-U contains no trivial component K1. The high order edge connectivity Ni, i1, is the number of edge outsets of size i. TO determine all Ni, i 1, for a general graph is NP-hard. In this paper, the authors evaluated the restricted edge connectivity and the high order edge connectivity Ni, 1 i -1, for any connected Abelian Cayley graphs explicitly.
文摘We investigate here various kinds of semi-product subgroups of Poincar6 group in the scheme of Cohen-Glashow＇s very special relativity along the deformation approach by Gibbons- Gomis-Pope. For each proper Poincar6 subgroup which is a semi-product of proper lorentz group with the spacetime translation group T（4）, we investigate all possible deformations and obtain all the possible natural representations inherited from the 5 - d representation of Poincar6 group. We find from the obtained natural representation that rotation operation may have additional accompanied scale transformation when the original Lorentz subgroup is deformed and the boost operation gets the additional accompanied scale transformation in all the deformation cases. The additional accompanied scale transformation has a strong constrain on the possible invariant metric function of the corresponding geometry and the field theories in the spacetime with the corresponding geometry.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 10775140,10705048,10731080,10975141,11175245,11075206the President Fund of GUCASthe Fundamental Research Funds for the Central Universities under Grant No. 105116
文摘The second Poincard kinematical group serves as one of new ones in addition to the known possible kinematics. The geometries with the second Poincard symmetry is presented and their properties are analyzed. On the geometries, the new mechanics based on the principle of relativity with two universal constants （c, l） can be established.
