Generalized scalar operators were introduced by C. Foia~ [4] and a detailed study of such operators can be found in the monograph [3]. An important subclass consists of regular generalized scalar operators which enjoy properties not shared by all generalized scalar operators. For example, the sum and product of commuting generalized scalar operators S and T need not be generalized scalar operat...

After extensive investigation on the Floquet second-order topological insulator (FSOTI) in two dimension (2D), here we propose driving schemes to systematically engineer hierarchy of first-order insulator, FSOTI, and third-order three (3D). Our protocols allow these phases showcase regular $0$, anomalous $\pi$, hybrid $0$-$\pi$-modes a unified phase diagram, obtained for both 2D 3D systems, whi...

In this paper we study various simplicial complexes associated to the commutative structure of a finite group G. We define NC(G) (resp. C(G)) as the complex associated to the poset of pairwise non-commuting (resp. commuting) sets of nontrivial elements in G. We observe that NC(G) has only one positive dimensional connected component, which we call BNC(G), and we prove that BNC(G) is simply conn...

The spatial distribution of households and firms, or urban spatial structure, is a core element of the study of urban economics and the crucial determinant of commuting patterns. This paper examines developments in the analysis of urban spatial structure and commuting that are related to the urban labour market that is the analysis of labour supply and labour demand in a spatial context. These ...

BACKGROUND Increasing active transport behavior (walking, cycling) throughout the life-course is a key element of physical activity promotion for health. There is, however, a need to better understand the correlates of specific domains of walking and cycling to identify more precisely at-risk populations for public health interventions. In addition, current knowledge of interactions between dom...

An unsettled conjecture of V. Bergelson and I. Håland proposes that if (X,A, μ,T) is an invertible weak mixing measure preserving system, where μ(X) < ∞, and if p1, p2, . . . , pk are generalized polynomials (functions built out of regular polynomials via iterated use of the greatest integer or floor function) having the property that no pi , nor any pi − p j , i 6= j, is constant on a set of p...

In this paper the dynamical noninvariance group SO(4, 2) for a hydrogen-like atom is derived through two different approaches. The first one is by an established traditional ascent process starting from the symmetry group SO(3). This approach is presented in a mathematically oriented original way with a special emphasis on maximally superintegrable systems, N-dimensional extension and little gr...

We study the distribution Pi(n)(D) of airway diameters D as a function of generation N in asymmetric airway trees of mammalian lungs. We find that the airway bifurcations are self-similar in four species studied. Specifically, the ratios of diameters of the major and minor daughters to their parent are constants independent of N until a cutoff diameter is reached. We derive closed form expressi...

This paper documents a little-noticed feature of US labor markets—very large variation in the labor supply of married women across cities. We focus on cross-city differences in commuting times as a potential explanation for this variation. We start with a model in which commuting times introduce non-convexities into the budget set. Empirical evidence is consistent with the model’s predictions: ...