So a 5d fluid is introduced to balance the gravity from the two branes . and a class of exact bulk solutions is obtained . by requiring a 4d effective curvature to have a minimum , the compactification size of the extra dimension is discussed 为平衡两个膜之间的引力,我们在bulk中引入了五维流体并得出了一族bulk精确解;由有效四维曲率的极小值条件,我们讨论了额外维的紧致大小。
2.
In this paper , the best contribution is to discover that the cofinalities of elements of minimal linearly compactification of go - space exactly reflect the properties of go - space . thus we can set up the relation between go - space and ordinals and resolve some problems which are not resolved by predecessors 但对go -空间的研究还有许多尚待解决的问题,本文的主要工作是发现了go -空间的最小线性序紧化中点的共尾数能很好的反映go空间的性质,从而把go -空间和序数联系了起来,解决了前人遗留的一系列问题。
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Reviewing exiting concepts and theories about agricultural supply chain , a classification criterion is presented , in consideration of complexity , of compactification , of reliability , and of optimization . based on existing eoq , a new two - stage model and its solution are given . this model takes into account the seasonal variety of products demand 本文首先回顾了有关农业供应链和农产品库存的相关概念、库存理论和农业库存模型研究的现状;分别从供应链的复杂度、供应链节点企业集中程度、供应链的可靠度和优化目标不同四个方面提出了供应链结构的分类标准。
4.
Witten ' s open string field theory formulate the interaction of bosonic open strings in the language of noncommutative geometry . compactification of matrix theory on the noncommutative torus was argued to correspond to supergravity with constant background three form tensor field . more generally , it has been realised that noncommutative gauge theory arises in the worldvolume theory on d - brane in the presence of a constant background b field in string theory Witten的开弦场论用非对易几何描述了玻色开弦的相互作用;在非对易torus上的矩阵理论的紧化对应于带有常数三形式张量场的超引力;更为普遍的,非对易规范理论可以自然地产生在带有常数b背景场的三维d - brane上。