5589315
Chromatic uniqueness of the complements of certain forests
Abstract A tree is called a tree of T -shape if its degree sequence is (1,1,1,2,2, …, 2,3). In this paper, we prove that the complement of the disjoint union of any number copies of a kind of tree of T -shape is chromatically unique by studying its adjoint polynomial.
17735073
On problems and conjectures on adjointly equivalent graphs
For a graph G, let h(G,x) denote its adjoint polynomial and @b(G) denote the minimum real root of h(G,x). Two graphs H and G are said to be adjointly equivalent if h(H,x)=h(G,x). Let F"1={G|@b(G)>-4} and F"2={G|@b(G)>=-4}. In this paper, we give a necessary and sufficient condition for two graphs H and G in F"i to be adjointly equivalent, where i=1,2. We also solve some problems and conjectures proposed by Dong et al. (Discrete Math. 258 (2002) 303-321).
1352172
Spectral Sequencing Based on Graph Distance
The construction of linear mesh layouts has found various applications, such as implicit mesh filtering and mesh streaming, where a variety of layout quality criteria, e.g., span and width, can be considered. While spectral sequencing, derived from the Fiedler vector, is one of the best-known heuristics for minimizing width, it does not perform as well as the Cuthill-Mckee (CM) scheme in terms of span. In this paper, we treat optimal mesh layout generation as a problem of preserving graph distances and propose to use the subdominant eigenvector of a kernel (affinity) matrix for sequencing. Despite the non-sparsity of the affinity operators we use, the layouts can be computed efficiently for large meshes through subsampling and eigenvector extrapolation. Our experiments show that the new sequences obtained outperform those derived from the Fiedler vector, in terms of spans, and those obtained from CM, in terms of widths and other important quality criteria. Therefore, in applications where several such quality criteria can influence algorithm performance simultaneously, e.g., mesh streaming and implicit mesh filtering, the new mesh layouts could potentially provide a better trade-off.
30610002
INQUIRY-BOUNDED MINING OF IMPRECISE DATA FOR ADAPTIVE INFORMATION MONITORING
Information monitoring (IM) is an essential activity for management and control. Generally speaking, an IM system aims to continuously check for information updates. Once an update is detected, it triggers suitable actions such as exception validation, exception handling, and user notification. Since information sources (e.g., individual persons and servers) often cannot notify the IM system of updates, the IM system needs to actively inquire about the current status of the items being monitored. However, data inquiry may be costly, and uncontrolled inquiry may even exhaust the information sources. IM should thus be conducted under an inquiry-bounded constraint (i.e., limiting the number of inquiries). Under such a constraint, an IM system should inquire the right targets at the right time by adapting to the update behavior (i.e., rough update frequency at each time period) of each information item. This requirement brings a significant challenge to the design of the IM system: mining the imprecise data that is sampled in an inquiry-bounded manner. The data is imprecise in the sense that information sources often cannot indicate when, how many, and how frequently updates really happened. We tackle the challenge by developing a scalable multiagent model in which each agent performs autonomous mining and cooperative monitoring. It significantly outperforms state-of-the-art IM techniques in capturing a higher percentage of updates in a timelier manner by conducting fewer inquiries.
22077737
Collaborative Multiagent Adaptation for Business Environmental Scanning Through the Internet
Businesses should promptly respond to their dynamic environments. Environmental scanners are thus essential for the businesses to discover and monitor environmental information of interest (IOI). In this paper, we explore user-centered, continuous and resource-bounded environmental scanning (UCRES). Upon receiving information preferences of managers, new IOI should be continuously detected in a timely and complete manner without consuming too much resource (e.g. bandwidths of computer networks and services of information servers). We develop a multiagent framework AESA to tackle the challenges of UCRES. Each agent is a simple entity. All agents collaboratively adapt their population and resource consumption to several dynamic aspects of UCRES: information preferences of individual users, resource limitation of environmental scanning, distribution of IOI in the environments, and update behaviors of the IOI. The delivery of AESA to businesses may constantly provide a larger amount of important and timely IOI without exhausting the Intranet and the Internet communities.
5842841
Incremental mining of information interest for personalized web scanning
Businesses and people often organize their information of interest (IOI) into a hierarchy of folders (or categories). The personalized folder hierarchy provides a natural way for each of the users to manage and utilize his/her IOI (a folder corresponds to an interest type). Since the interest is relatively long-term, continuous web scanning is essential. It should be directed by precise and comprehensible specifications of the interest. A precise specification may direct the scanner to those spaces that deserve scanning, while a specification comprehensible to the user may facilitate manual refinement, and a specification comprehensible to information providers (e.g. Internet search engines) may facilitate the identification of proper seed sites to start scanning. However, expressing such specifications is quite difficult (and even implausible) for the user, since each interest type is often implicitly and collectively defined by the content (i.e. documents) of the corresponding folder, which may even evolve over time. In this paper, we present an incremental text mining technique to efficiently identify the user's current interest by mining the user's information folders. The specification mined for each interest type specifies the context of the interest type in conjunctive normal form, which is comprehensible to general users and information providers. The specification is also shown to be more precise in directing the scanner to those sites that are more likely to provide IOI. The user may thus maintain his/her folders and then constantly get IOI, without paying much attention to the difficult tasks of interest specification and seed identification.
8117936
Adaptive Agents for Effective Information Monitoring
Information motoring is an essential basis for management and decision making in various domains. Once an information update is detected, suitable procedures may be triggered to identify potential problems and opportunities. In this paper, we define effective information monitoring (EIM) and explore how adaptive agents may cooperate with each other in order to achieve their collective goal of EIM. Since each information item may be updated by various entities (e.g. information servers) at any time, EIM calls for a multiagent system that may detect more information updates in a timely manner using a controlled amount of system resources (e.g. loading of related information servers and the Intranet). To achieve EIM, the agents should adapt themselves to the dynamically changing behaviors of the information items being monitored. They learn to issue requests of using system resources and concede to those agents that are more likely to detect updates at the time of negotiation. The framework is theoretically ...