We present an algorithm for characterising the generalised Dirichlet to Neumann map for moving initial-boundary value problems. This algorithm is derived by combining the so-called global relation, which couples the initial and boundary values of the problem, with a new method for inverting certain one-dimensional integrals. This new method is based on the spectral analysis of an associated ODE...

In boundary labeling, each point site in a rectangular map is connected to a label outside the map by a leader, which may be a rectilinear or a straight-line segment. Among various types of leaders, the so-called type-opo leader consists of three segments (from the site to its associated label) that are orthogonal, then parallel, and then orthogonal to the side to which the label is attached. I...

We study hyperbolic maps depending on a parameter ε. Each of them has an invariant Cantor set. As ε tends to zero, the map approaches the boundary of hyperbolicity. We analyze the asymptotics of scaling function of the invariant Cantor set as ε goes to zero. We show that there is a limiting scaling function of the limiting map and this scaling function has dense jump discontinuities because the...

The goal is to collect pearls (small golden circles) by sliding a droplet of water (large blue circle) over them in a grid map. The map contains obstacles (square blocks). In each move, the droplet slides in one of the four directions to the maximal extent, until it is stopped by an obstacle. 7 Moves! left (1st pearl) up, left (2nd pearl) down, right, up, left (3rd pearl) The map contains only ...

Separation of the B component of a cosmic microwave background (CMB) polarization map from the much larger E component is an essential step in CMB polarimetry. For a map with incomplete sky coverage, this separation is necessarily hampered by the presence of ambiguous modes which could be either E or B modes. I present an efficient pixel-space algorithm for removing the ambiguous modes and sepa...

In this paper we study families of multi-modal 1D maps following the setting of Wang and Young [20]. Under a mild combinatoric assumption, we prove that for generic one parameter families of 1D maps containing a Misiurewicz map, parameters of non-uniformly expanding maps, the measure abundance of which was proved previously in [20], are accumulation points of paramaters admitting super-stable p...

The purpose of this note is to establish, in a categorical manner, the universality of the Geroch-Kronheimer-Penrose causal boundary when considering the types of causal structures that may profitably be put on any sort of boundary for a spacetime. Actually, this can only be done for the future causal boundary (or the past causal boundary) separately; furthermore, only the chronology relation, ...

Weak instruments arise when the instruments in linear instrumental variables (IV) regression are weakly correlated with the included endogenous variables. In generalized method of moments (GMM), more generally, weak instruments correspond to weak identification of some or all of the unknown parameters. Weak identification leads to GMM statistics with nonnormal distributions, even in large sampl...