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21.
22.
何天祥 《数学的实践与认识》2011,41(11)
根据区域产业分工理论,运用区位商测定区域专业化程度.然后,基于复杂系统结构熵理论,从产业在区际和区内聚集分布信息出发,融合行业路径和地区路径分析法于一体,提出并证明了可以用区位结构熵全面衡量产业在空间上的分布状况.在此基础上,构建一维区域分工指数,综合测定区域分工水平.最后,以我国工业空间分布为例,例证了该方法是合理的、可行的,具有一定的推广和应用价值. 相似文献
23.
24.
Klaus D. Wutzke Kerstin V. Schmidek 《Isotopes in environmental and health studies》2017,53(6):553-562
A resistant starch (RS) mixture (MIX) consisting of fibre of potatoes (FP) and wrinkled pea starch (WPS), and high amylose maize starch (HAMS) were supplemented in adults to evaluate their effects on fat oxidation by means of a 13CO2-breath test. Sixteen subjects received a regular diet either without or with the supplementation of MIX and HAMS in randomised order. After administration of a [U-13C]algal lipid mixture, exhaled air was collected over 14?h in 0.5- and 1-h intervals. The 13C abundances were measured by nondispersive infrared spectroscopy. In comparison to the dry run (DR), supplementation with MIX and with HAMS increased the cumulative percentage dose recovery: (DR: 16.7?%, MIX: 16.9?%, HAMS: 18.0?%), but without statistical significance. The colonic degradation of MIX and HAMS to short-chain fatty acids tends to lower the formation of carbohydrate-derived acetyl-CoA and contributes to a postprandial lipid oxidation increase by using fat-derived acetyl-CoA as a compensatory fuel source. 相似文献
25.
Let X be a closed, oriented Riemannian 4-manifold. Suppose that a cyclic group Z(
p
(p is prime) acts on X by an orientation preserving isometry with an embedded Riemann surface as fixed point set. We study the representation of Z
p
on the Spinc-bundles and the Z
p-invariant moduli space of the solutions of the Seiberg–Witten equations for a Spinc-structure X. When the Z
p
action on the determinant bundle det L acts non-trivially on the restriction L| over the fixed point set , we consider -twisted solutions of the Seiberg-Witten equations over a Spinc-structure ' on the quotient manifold X/Z
p
X', (0,1). We relate the Z
p
-invariant moduli space for the Spinc-structure on X and the -twisted moduli space for the Spinc-structure on X'. From this we induce a one-to-one correspondence between these moduli spaces and calculate the dimension of the -twisted moduli space. When Z
p
acts trivially on L|, we prove that there is a one-to-one correspondence between the Z
p
-invariant moduli space M(
Zp
and the moduli space M (") where ' is a Spinc-structure on X' associated to the quotient bundle L/Z
p
X'. vskip0pt When p = 2, we apply the above constructions to a Kahler surface X with b
2
+
(X) > 3 and H
2(X;Z) has no 2-torsion on which an anti-holomorphic involution acts with fixed point set , a Lagrangian surface with genus greater than 0 and []2H
2(H ;Z). If
K
X
2 > 0 or K
X
2
= 0 and the genus g()> 1, we have a vanishing theorem for Seiberg–Witten invariant of the quotient manifold X'. When K
X
2
= 0 and the genus g()= 1, if there is a Z
2-equivariant Spinc-structure on X whose virtual dimension of the Seiberg–Witten moduli space is zero then there is a Spinc-structure " on X' such that the Seiberg-Witten invariant is ±1. 相似文献
26.
We consider the Riemannian universal covering of a compact manifold M = X/ and assume that is amenable. We show the existence of a (nonrandom) integrated density of states for an ergodic random family of Schrödinger operators on X. 相似文献
27.
Belmesnaoui Aqzzouz 《Applied Categorical Structures》2002,10(6):603-616
We define the -product of a -space by a quotient Banach space. We give conditions under which this -product will be monic. Finally, we define the
c
-product of a Schwartz b-space by a quotient Banach space and we give some examples of applications. 相似文献
28.
29.
We study the class of cyclically presented groups which contain Fibonacci groups and Sieradski groups. Conditions are specified for these groups to be finite, pairwise isomorphic, or aspherical. As a partial answer to the question of Cavicchioli, Hegenbarth, and Repov, it is stated that there exists a wide subclass of groups with an odd number of generators cannot appear as fundamental groups of hyperbolic three-dimensional manifolds of finite volume. 相似文献
30.
Let R be a commutative ring without nil-factor. In this paper, we discuss the problem of quasi-valuation ring presented in the reference “Wang Shianghaw, On quasi-valuation ring, Northeast People‘s Univ. Natur. Sci. J., (1)(1957), 27-40”,when the quotient field of R is an algebraic number field or an algebraic function field, and we obtain a characterization of quasi-valuation rings. 相似文献