The Cops and Robbers game as originally defined independently by Quilliot and by Nowakowski andWinkler in the 1980s has beenmuch studied, but very few results pertain to the algorithmic and complexity aspects of it. In this paper we prove that computing the minimumnumber of cops that are guaranteed to catch a robber on a given graph is NP-hard and that the parameterized version of the problem i...

Communities of Practices (CoPs) are informal structures within organizations that bind people together through informal relationships and the sharing of expertise and experience. As such, they are effective tools for the creation and sharing of organizational knowledge, and, increasingly, organizations are adopting them as part of their knowledge management strategies. In this paper, we examine...

We theoretically analyze the Cops and Robber Game for the first time in a multidimensional grid. It is shown that in an n-dimensional grid, at least n cops are necessary if one wants to catch the robber under all possible initial configurations. We also present a set of cop strategies for which n cops are provably sufficient to catch the robber.

Cryptosporidiosis is predominantly caused by two closely related species of protozoan parasites the zoonotic Cryptosporidium parvum and anthroponotic Cryptosporidium hominis which diverge phenotypically in respect to host range and virulence. Using comparative genomics we identified two genes displaying overt heterogeneity between species. Although initial work suggested both were species speci...

Communities of practice (CoPs) are increasingly recognised as an important mechanism through which goods are created. Current conceptualisations of CoPs don’t, however, acknowledge adequately the inherent tensions between practices and the organisations within which they function. This failure leads to an inadequate understanding of ways in which organisations should interact with relevant CoPs...

This paper reviews prior research on individual participation in online communities of practice (CoPs). It examines how the concept of CoP has been applied in IS and what theories have been applied to explain knowledge sharing behaviours in online CoPs. To integrate findings in prior empirical IS studies, the paper drew on literature on relationship marketing to re-conceptualize participation i...

The COPS (Classification Of Protein Structures) web server provides access to the complete repertoire of known protein structures and protein structural domains. The COPS classification encodes pairwise structural similarities as quantified metric relationships. The resulting metrical structure is mapped to a hierarchical tree, which is largely equivalent to the structure of a file browser. Exp...

In this short paper we study the game of cops and robbers, which is played on the vertices of some fixed graph G. Cops and a robber are allowed to move along the edges of G, and the goal of cops is to capture the robber. The cop number cðGÞ of G is the minimum number of cops required to win the game. Meyniel conjectured a long time ago thatOð ffiffiffi n p Þ cops are enough for any connectedG o...

In this paper, we study the vertex pursuit game of Cops and Robbers where cops try to capture a robber loose on the vertices of a graph. The minimum number of cops required to win on a given graph G is the cop number of G. We present asymptotic results for the game of Cops and Robbers played on a random graph G(n, p) focusing on the case when the cop number does not grow with the size of a grap...