35387631
A lower bound on connectivities of matroid base graphs
Abstract The connectivity of a graph G and the corank of a matroid M are denoted by κ ( G ) and ϱ , respectively. It is shown that if a graph G is the base graph of a simple matroid M , then κ ( G )⩾2 ϱ and the lower bound of 2 ϱ is best possible.
1047063
Generalization of matching extensions in graphs
Abstract Let G be a graph with vertex set V(G) . Let n, k and d be non-negative integers such that n+2k+d⩽|V(G)|−2 and |V(G)|−n−d is even. A matching which covers exactly |V(G)|−d vertices of G is called a defect - d matching of G . If when deleting any n vertices of G the remaining subgraph contains a matching of k edges and every k -matching can be extended to a defect- d matching, then G is called a (n,k,d) - graph . In this paper a characterization of (n,k,d) -graphs is given and several properties (such as connectivity, minimum degree, hierarchy, etc.) of (n,k,d) -graphs are investigated.
11215369
A note on the least number of edges of 3-uniform hypergraphs with upper chromatic number 2
The upper chromatic number @g@?(H) of a hypergraph H=(X,E) is the maximum number k for which there exists a partition of X into non-empty subsets X=X"1@?X"2@?...@?X"k such that for each edge at least two vertices lie in one of the partite sets. We prove that for every n>=3 there exists a 3-uniform hypergraph with n vertices, upper chromatic number 2 and @?n(n-2)/3@? edges which implies that a corresponding bound proved in [K. Diao, P. Zhao, H. Zhou, About the upper chromatic number of a co-hypergraph, Discrete Math. 220 (2000) 67-73] is best-possible.
5451258
Toughness and Perfect Matchings in Graphs
11364817
A class of mobile motion prediction algorithms for wireless mobile computing and communications
This paper describes a class of novel mobile motion prediction algorithms for supporting global mobile data accessing. Traditionally, mobility and routing management includes functions to passively keep track of the location of the users/terminals and to maintain connections to the terminals belonging to the system. To maintain uninterrupted high-quality service for distributed applications, it is important that a mobile system be more intelligent and can anticipate the change of the location of its user. We propose an aggressive mobility and routing management scheme, called predictive mobility management. A class of mobile motion prediction algorithms predicts the “future” location of a mobile user according to the user's movement history, i.e., previous movement patterns. By combining this scheme with mobility agent functions, the service and user routing data are actually pre-connected and pre-assigned at the locations to which the user is moving. Thus, the user can immediately receive service or data with virtually the same efficiency as at the previous location, i.e., without encountering a large “data structure handover” delay before service or data is available.
14839466
Algorithms for large-scale genotyping microarrays
MOTIVATION
Analysis of many thousands of single nucleotide polymorphisms (SNPs) across whole genome is crucial to efficiently map disease genes and understanding susceptibility to diseases, drug efficacy and side effects for different populations and individuals. High density oligonucleotide microarrays provide the possibility for such analysis with reasonable cost. Such analysis requires accurate, reliable methods for feature extraction, classification, statistical modeling and filtering.


RESULTS
We propose the modified partitioning around medoids as a classification method for relative allele signals. We use the average silhouette width, separation and other quantities as quality measures for genotyping classification. We form robust statistical models based on the classification results and use these models to make genotype calls and calculate quality measures of calls. We apply our algorithms to several different genotyping microarrays. We use reference types, informative Mendelian relationship in families, and leave-one-out cross validation to verify our results. The concordance rates with the single base extension reference types are 99.36% for the SNPs on autosomes and 99.64% for the SNPs on sex chromosomes. The concordance of the leave-one-out test is over 99.5% and is 99.9% higher for AA, AB and BB cells. We also provide a method to determine the gender of a sample based on the heterozygous call rate of SNPs on the X chromosome. See http://www.affymetrix.com for further information. The microarray data will also be available from the Affymetrix web site.


AVAILABILITY
The algorithms will be available commercially in the Affymetrix software package.
6438586
A mobile virtual-distributed system architecture for supporting wireless mobile computing and communications
This paper describes a novel mobile virtual-distrubuted system architecture for supporting global mobile computing and communications. the principal contribution of this paper is to innovatively apply virtual memory concepts to mobile systems by deploying mobile-floating agents to de-couple services and resources from the underlying network and allow them to move around following their mobile users. The mobile-floating agents maintain data structures associated with a mobile user. By combining the mobile-floating agent functions with a predictive mobility management algorithm and location-aware caching and prefetching, services and user data structure are pre-connected and pre-assigned at the locations to which the user is moving. Thus, the users can maintain their data structures or immediately receive service with virtually the same efficiency as at the previous location.
1940922
On the scalability of network management information for inter-domain light-path assessment
We investigate the necessary amount of network management information for light-path assessment to dynamically set up end-to-end light-paths across administrative domains in optical networks. Our focus is on the scalability of partial management information. We pose light-path assessment as a decision problem, and define the performance as the Bayes probability of an erroneous decision. We then characterize the scalability of management information as its growth rate with respect to the total resources of the network to achieve a desired performance. Scalability is achieved if the management information needed is only a negligible fraction of the total network resources. Specifically, we consider in this work one type of partial information that grows only logarithmically with the number of wavelengths supported per link. We derive an upper bound for the Bayes error in terms of the blocking probability when a new call is presented at the entrance of the network. We evaluate the upper bound using both independent and dependent models of wavelength usage for intra- and inter-domain calls. Our study shows that there exists a "threshold effect": The Bayes error decreases to zero exponentially with respect to the load when the load is either below or above a threshold value; and is nonnegligible when the load is in a small duration around the threshold. This suggests that the partial information considered can indeed provide the desired performance, and a small percentage of erroneous decisions can be traded off to achieve a large saving in the amount of management information.
232914
Active and real-time functionalities for electronic brokerage design
In this position paper, we discuss an architecture for developing next generation electronic brokerages using active and real-time functionalities. These electronic brokerages support timeliness requirements and allow users to express complex preferences. User preferences can be conveniently captured as event-condition-action (ECA) rules. The design allows pro-active monitoring of user preferences and execution of actions in a timely manner. A proof-of-concept prototype is implemented using Java in the context of online trading. The prototype consists of three major components: rule validator, active rule manager and event monitor.