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991.
For a given polyhedron K(?)M,the notation RM(K)denotes a regular neigh- borhood of K in M.The authors study the following problem:find all pairs(m,k) such that if K is a compact k-polyhedron and M a PL m-manifold,then R_M(f(K))≌R_M(g(K))for each two homotopic PL embeddings f,g:K→M.It is proved that R_S~(k 2)(S~k)(?)S~k×D~2 for each k(?)2 and some PL sphere S~k(?)S~(k 2)(even for any PL sphere S~k(?)S~(K 2)having an isolated non-locally flat point with the singularity S~(k-1)(?) S~(k 1)such thatπ_1(S~(k 1)-S~(k-1))(?)Z). 相似文献
992.
Chun-Gil Park 《数学物理学报(B辑英文版)》2003,23(1)
All C*-algebras of sections of locally trivial C* -algebra bundles over ∏i=1sLki(ni) with fibres Aw Mc(C) are constructed, under the assumption that every completely irrational noncommutative torus Aw is realized as an inductive limit of circle algebras, where Lki (ni) are lens spaces. Let Lcd be a cd-homogeneous C*-algebra over whose cd-homogeneous C*-subalgebra restricted to the subspace Tr × T2 is realized as C(Tr) A1/d Mc(C), and of which no non-trivial matrix algebra can be factored out.The lenticular noncommutative torus Lpcd is defined by twisting in by a totally skew multiplier p on Tr+2 × Zm-2. It is shown that is isomorphic to if and only if the set of prime factors of cd is a subset of the set of prime factors of p, and that Lpcd is not stablyisomorphic to if the cd-homogeneous C*-subalgebra of Lpcd restricted to some subspace LkiLki (ni) is realized as the crossed product by the obvious non-trivial action of Zki on a cd/ki-homogeneous C*-algebra over S2ni+1 for ki an integer greater than 相似文献
993.
Let An be the group of n×n even permutation matrices, and let Vn be the real linear space spanned by An. The purpose of this note is to characterize those linear operators φ on Vn satisfying φ(An)=An. This answers a question raised by C.K. Li, B.S. Tam, N.K. Tsing [Linear Algebra Appl., to appear]. 相似文献
994.
Yukari Oda Shokyoku Kanaoka Sadahito Aoshima 《Journal of polymer science. Part A, Polymer chemistry》2010,48(5):1207-1213
For the precision synthesis of primary amino functional polymers, cationic polymerization of a phthalimide‐containing vinyl ether monomer precursor, 2‐vinyloxyethyl phthalimide (PIVE), was examined using a base‐assisting initiating system. Living polymerization of PIVE in CH2Cl2 in the presence of 1,4‐dioxane as an added base yielded nearly monodispersed polymers (Mw/Mn < 1.1) and higher molecular weight polymers, which have never been obtained using other initiating systems. Furthermore, block copolymers with hydrophobic or hydrophilic groups could be prepared. The deprotection of the pendant phthalimide groups gave well‐defined pH‐responsive polymers with pendant primary amino groups. Dual‐stimuli–responsive block copolymers having a pH‐responsive polyamine segment and a thermosensitive segment self‐assembled in water in response to both pH and temperature. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1207–1213, 2010 相似文献
995.
Dmitrij V. Soroka Vyacheslav A. Soroka 《Physics letters. [Part B]》2012,707(1):160-162
An approach to the cosmological term problem is proposed, using the gauge semi-simple tensor extension of the D-dimensional Poincaré group as a basis. 相似文献
996.
997.
The present paper begins by deriving an instantaneous formulation for the backward-looking (reinforcement based learning) satisfaction balance model of Gray and Tallman (1984). This model is then used to generate interactional data from four simulated agents in a network interaction experiment. Because this initial model does not generate stable interaction structures in the network experiment, it is altered step by step in the direction of a forward-looking (agent with goals) model that has been shown to generate such stable interaction structures. The purpose of the modifications are to learn what aspects of the forward-looking model are needed to evolve a stable interaction structure, and to learn how these aspects may be incorporated into a model that remains essentially reinforcement based. 相似文献
998.
Peter Maier 《Geometriae Dedicata》2000,83(1-3):217-228
We describe necessary and sufficient conditions under which a topological translation structure obtained from a Lie group with planar partition can be turned into a stable plane, thereby proving a conjecture due to Stroppel. 相似文献
999.
John P. Lehoczky 《The Journal of mathematical sociology》2013,37(2):139-157
A class of models called interactive Markov chains is studied in both discrete and continuous time. These models were introduced by Conlisk and serve as a rich class for sociological modeling, because they allow for interactions among individuals. In discrete time, it is proved that the Markovian processes converge to a deterministic process almost surely as the population size becomes infinite. More importantly, the normalized process is shown to be asymptotically normal with specified mean vector and covariance matrix. In continuous time, the chain is shown to converge weakly to a diffusion process with specified drift and scale terms. The distributional results will allow for the construction of a likelihood function from interactive Markov chain data, so these results will be important for questions of statistical inference. An example from manpower planning is given which indicates the use of this theory in constructing and evaluating control policies for certain social systems. 相似文献
1000.
<正>Two new cage compounds,4-trinitroethyl-10-nitro-2,6,8,12-tetraacetylhexaazaisowurtzitane(3) and 4-trinitroethyl- 2,6,8,10,12-pentanitrohexaazaisowurtzitane(4),containing trinitromethyl group were synthesized by a novel method,and their structures were confirmed by IR,~1H NMR,MS and single crystal X-ray.DSC result shows that compound 4 has surprising thermal stability and could be a potential energetic compound. 相似文献