In this paper, we describe the BBN BYBLOS system used for the 1998 Hub-4E primary and Hub-4Sp evaluation benchmarks, and discuss the improvements made to the system in 1998. We focus on the techniques that were new in this year’s system, including processing of the acoustic training data, test segmentation, revised cepstral normalization and Vocal Tract Length Normalization (VTLN), band-specifi...

Capacitated versions of Vertex Cover and Dominating Set have been studied intensively in terms of polynomial time approximation algorithms. Although the problems Dominating Set and Vertex Cover have been subjected to considerable scrutiny in the parameterized complexity world, this is not true for their capacitated versions. Here we make an attempt to understand the behavior of the problems Cap...

The airlines reorganization will accelerate the switch of the Chinese mainland civil aviation system from a former point-to-point (PP) structure to a hub-and-spoke (HS) network. In such a context, the major efforts of our paper are put into identifying hub airports in mainland China. We first analyze the HS network’s competitive advantages and find four desirable hub characteristics. A three-le...

Many graph problems seek subsets of their vertices that maximize or minimize objective functions on the vertices. Among these are the capacitated p-median problem, the geometric connected dominating set problem, the capacitated k-center problem, and the traveling tourist problem. Prior genetic algorithms research in this area applied a simple mutation of an allele by random replacement. Recentl...

Let $G$ be a finite non-abelian $p$-group and $L(G)$ denotes the absolute center of $G$. Also, let $Aut^{L}(G)$ and $Aut_c(G)$ denote the group of all absolute central and the class preserving automorphisms of $G$, respectively. In this paper, we give a necessary and sufficient condition for $G$ such that $Aut_c(G)=Aut^{L}(G)$. We also characterize all finite non-abelian $p$-groups of order $p^...

IEEE 802.16, also known as WiMAX (Worldwide Inter-operability for Microwave Access), is a new wireless access technology for current increasing demand of wireless high-speed broadband service. Efficient and effective deployment of such a network to service an area of users with certain traffic demands is an important network planning problem. This network planning can be formulated in a similar...