Paper provides technical means of digitized approximation of sensing area coverage subsystem in WSN (wireless sensor networks). Approximate coverage versus to complete cover is acceptable for some applications and the use of approximations can extend the network lifetime. The digitized approximation is considered as an alternative to the analytic, set cover, Voronoi diagram based and other tech...

This paper presents empirical evidence on how education is related to income distribution in a panel data set covering a broad range of countries for the period between 1960 and 1990. The findings indicate that educational factors—higher educational attainment and more equal distribution of education—play a significant role in making income distribution more equal. The results also confirm the ...

Local sourcing from indigenous firms by multinational enterprises (MNEs) is an important channel through which the former may benefit from the positive externalities generated by the latter. Employing a special survey data set covering 493 multinational subsidiaries in China for the period 1999-2005, this paper investigates the determinants of local sourcing. It is found that the extent to whic...

Abstract. A general greedy approach to construct coverings of compact metric spaces by metric balls is given and analyzed. The analysis is a continuous version of Chvátal’s analysis of the greedy algorithm for the weighted set cover problem. The approach is demonstrated in an exemplary manner to construct efficient coverings of the n-dimensional sphere and n-dimensional Euclidean space to give ...

The Set Cover problem has as input a set R of m items, a set C of n subsets of R and a weight function w : C → IR. The task is to choose a subset C ′ ⊆ C of minimum weight whose union contains all items of R. The sets R and C can be represented by an m × n binary matrix A that consists of a row for every item in R and a column for every subset of R in C, where an entry ai,j is 1 iff the ith ite...

Bright Minds, Big Rent: Gentrification and the Rising Returns to Skill* In 1980, housing prices in the main US cities rose with distance to the city center. By 2010, that relationship had reversed. We propose that this development can be traced to greater labor supply of high-income households through reduced tolerance for commuting. In a tractlevel data set covering the 27 largest US cities, y...

We give improved hitting-sets for two special cases of Read-once Oblivious Arithmetic Branching Programs (ROABP). First is the case of an ROABP with known variable order. The best previously known hitting-set for this case had size (nw) where n is the number of variables and w is the width of the ROABP. Even for a constant-width ROABP, nothing better than a quasi-polynomial bound was known. We ...

This work deals with the Set Cover with Pairs Problem (SCPP) which is a generalization of the Set Cover Problem (SCP). In the SCPP the elements have to be covered by specific pairs of objects, instead of a single object. We propose a new mathematical formulation using extended variables that is capable of consistently solve instances with up to 500 elements and 500 objects. We also developed an...

In this note we provide a simpler proof of a probabilistic analysis of the set cover problem given in [6]. We also prove these results using the language of high probability instead of using convergence in probability or convergence almost everywhere, making the previous results more precise.