Orienteering is the following optimization problem: given an edge-weighted graph (directed or undirected), two nodes s, t and a time limit T , find an s-t walk of total length at most T that maximizes the number of distinct nodes visited by the walk. One obtains a generalization, namely orienteering with time-windows (also referred to as TSP with time-windows), if each node v has a specified ti...

We give new approximation algorithms for robot routing problems that are variants of the classical traveling salesperson problem (TSP). We are to find a path for a robot, moving at speed at most s, to visit a set V = {v1, . . . , vn} of sites, each having an associated time window of availability, [ri, di], between a release time ri and a deadline di. In the time-window prize collecting problem...

This paper presents a device proposal based on a junction between an absorbing semiconductor nanorod structure and another window semiconductor layer for solar cell application. The possibility of band gap tuning by varying the diameter of the nanorods along the length, higher absorption coefficient at nanodimensions, the presence of a strong electrical field at the nanorod-window semiconductor...

We consider the magnetic Schrödinger operator in a twodimensional strip. On the boundary of the strip the Dirichlet boundary condition is imposed except for a fixed segment (window), where it switches to magnetic Neumann1. We deal with a smooth compactly supported field as well as with the Aharonov-Bohm field. We give an estimate on the maximal length of the window, for which the discrete spect...

where C~ E R" ,xt R" , and gt E RP are the state, control, and measurement vectors, respectively. The initial state 5 is unknown. We assume that 5 E X and 5 E U , where X and U are compact sets. Now, let us consider a sliding-window observer. This means that, a t a given stage t and for a given temporal window of length N stages, we have to recovery c ~ ~ on the basis of the last N + 1 measurem...

Abstract Rolling-time-dummy (RTD) is a hedonic method used by number of countries to compute their official house price indexes (HPIs). The RTD requires less data and more adaptable than other methods, which makes it well suited for computing higher frequency HPIs (e.g., monthly or weekly). In this article, we address three key issues relating RTD. First, develop determining the optimal length ...