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71.
预测分析再生混凝土各组分对再生混凝土宏观力学参数的影响是开展再生混凝土基本力学性能的一种方式.为了分析再生混凝土各组分对再生混凝土宏观力学参数的影响,根据再生混凝土的细观结构组成,建立了细观等效模型,利用扭转变形、细观夹杂理论、弹性等效思想和M-T模型方法,推导了由原生骨料、老界面层、老水泥砂浆、新界面层和新水泥砂浆等组成的再生混凝土的宏观力学参数预测模型.预测结果表明,随着再生骨料的取代率增加,水泥砂浆的含量不断增加,再生混凝土孔隙率也随之增大,导致再生混凝土的Poisson比随之增大,弹性模量、剪切模量和体积模量不断降低.模型的预测结果较好地反映了再生混凝土宏观力学参数随再生骨料取代率的增加不断变化的这一趋势,也为再生混凝土宏观力学参数的预测提供了一条简单实用的新方法,有利于再生混凝土基本力学性能的研究分析. 相似文献
72.
We propose a Lyapunov control design to achieve specific (or a family of) unitary time-evolution operators, i.e., quantum gates in the Schrödinger picture by tracking control. Two examples are presented. In the first, we illustrate how to realize the Hadamard gate in a single-qubit system, while in the second, the controlled-NOT (CNOT) gate is implemented in two-qubit systems with the Ising and Heisenberg interactions. Furthermore, we demonstrate that the control can drive the time-evolution operator into the local equivalence class of the CNOT gate and the operator keeps in this class forever with the existence of Ising coupling. 相似文献
73.
Based on an idea of Rosenblatt, the methods of interpolation theory are used to establish moment inequalities and equivalence relations for measures of dependence between two or more families of random variables. A couple of “interpolation” theorems proved here appear to be new. 相似文献
74.
75.
76.
In this paper, we establish some new Foxby equivalences between some Gorenstein subcategories in the Auslander class 𝒜C(R) and that in the Bass class ?C(S) in a general setting. Our results provide a unification and generalization of some known results and generate some new Foxby equivalences of categories. 相似文献
77.
Manuel Abad Cecilia Rossana Cimadamore José Patricio Díaz Varela 《Central European Journal of Mathematics》2009,7(2):299-309
In this paper, every monadic implication algebra is represented as a union of a unique family of monadic filters of a suitable
monadic Boolean algebra. Inspired by this representation, we introduce the notion of a monadic implication space, we give
a topological representation for monadic implication algebras and we prove a dual equivalence between the category of monadic
implication algebras and the category of monadic implication spaces.
相似文献
78.
令R是左Gorenstein环.我们构造了奇点反导出模型范畴和奇点余导出模型范畴(见文[Models for singularity categories,Adv Math.,2014,254:187-232])之间的Quillen等价.作为应用,给出了投射,内射模的正合复形的同伦范畴之间的一个具体的等价■. 相似文献
79.
Frederick?M.?KronzEmail author Tracy?A.?Lupher 《International Journal of Theoretical Physics》2005,44(8):1239-1258
It has been maintained that the physical content of a model of a system is completely contained in the C∗-algebra of quasi-local observables
that is associated with the system. The reason given for this is that the unitarily inequivalent representations of
are physically equivalent. But, this view is dubious for at least two reasons. First, it is not clear why the physical content
does not extend to the elements of the von Neumann algebras that are generated by representations of
. It is shown here that although the unitarily inequivalent representations of
are physically equivalent, the extended representations are not. Second, this view detracts from special global features
of physical systems such as temperature and chemical potential by effectively relegating them to the status of fixed parameters.
It is desirable to characterize such observables theoretically as elements of the algebra that is associated with a system
rather than as parameters, and thereby give a uniform treatment to all observables. This can be accomplished by going to larger
algebras. One such algebra is the universal enveloping von Neumann algebra, which is generated by the universal representation
of
; another is the direct integral of factor representations that are associated with the set of values of the global features.
Placing interpretive significance on the von Neumann algebras mentioned earlier sheds light on the significance of unitarily
inequivalent representations of
, and it serves to show the limitations of the notion of physical equivalence. 相似文献
80.