35812356
A Study of How Domain Knowledge Improves Knowledge-Based Learning Systems
Abstract A knowledge-based learning system is developed to demonstrate that intelligently selecting a subset of examples based on domain knowledge for rule induction can be more productive than using all provided examples. Knowledge-based learning uses an incomplete domain theory and examples to induce knowledge missing in the theory. Knowledge-based learning systems determine where knowledge is missing in a domain theory, select a relevant subset of examples to use in induction, and induce new rules or modify existing rules.
28843712
Generalized Recursive Splitting Algorithms for Learning Hybrid Concepts
This paper describes the Competitive Relation Learner (CRL), a generalized recursive splitting algorithm capable of producing a wide range of hybrid concept representations through the competitive application of multiple learning strategies, multiple decomposition strategies, and multiple decomposition evaluation strategies. Experimental results are reported that demonstrate CRL's ability to outperform several well known fixed-bias strategies.
208798481
A Discourse Model For Collaborative Design
A Discourse Model, including a structure and a process, is developed that provides software support for collaborative engineering design. Components of the structure include a workspace that incorporates frames, constraints, semantic networks, libraries of sharable design objects, agents, and a Virtual Workspace Language. Components of the process include procedures for identifying agent interest sets, applying state transformations to the design model, switching design contexts, identifying conflicts between designers, and tracking resolved conflicts. The model is implementation-independent and applicable to many research and commercial design environments currently available. An example scenario is provided in the Architecture/ Engineering/ Construction domain that illustrates collaboration during the conceptual design of a fire station.
37627056
SWIFT: system workbench for integrating and facilitating teams
There have been many R&D efforts in recent years to develop computer environments that directly enhance group problem-solving productivity. An example of such efforts is the computer-based virtual teaming technology (VTT) developed at the knowledge-based Engineering Sytems Research Laboratory (KESRL). The core software environment for KESRL's VTT is called SWIFT and is based on the knowledge processing technology (KPT) previously developed at KESRL to support various engineering design tasks. SWIFT is a flexible environment which enables the rapid development of collaborative applications, linking workers in distributed environments, of many domains. The paper presents the overall system architecture of SWIFT, and introduces the current and future R&D efforts at KESRL in realizing SWIFT for significant industrial applications.<<ETX>>
12858200
Building Robust Learning Systems by Combining Induction and Optimization
Each concept description language and search strategy has an inherent inductive bias, a preference for some hypotheses over others. No single inductive bias performs optimally on all problems. This paper describes a system that couples induction with optimization to carry out an efficient search of large regions of inductive bias space. Experimental results are reported demonstrating the system's capacity to choose optimal biases even for complex and noisy problems.
12297349
Creating and using models for engineering design: a machine-learning approach
An adaptive and interactive modeling system (AIMS) that integrates simulation, optimization and machine learning to help engineers make design decisions is described. AIMS views engineering decision making as a two-phase process of creating and then using models. The competitive relation learner and the induce-and-select optimizer, AIMS's two main components, and their roles in both phases of decision-making are discussed. AIMS's role in supporting the design of a diesel engine that outputs power within the 440- to 460-kW range and consumes the least amount of fuel is also discussed.<<ETX>>
1262760
Providing robust and ubiquitous security support for mobile ad-hoc networks
Providing security support for mobile ad-hoc networks is challenging for several reasons: (a) wireless networks are susceptible to attacks ranging from passive eavesdropping to active interfering, occasional break-ins by adversaries may be inevitable in a large time window; (b) mobile users demand "anywhere, anytime" services; (c) a scalable solution is needed for a large-scale mobile network. In this paper, we describe a solution that supports ubiquitous security services for mobile hosts, scales to network size, and is robust against break-ins. In our design, we distribute the certification authority functions through a threshold secret sharing mechanism, in which each entity holds a secret share and multiple entities in a local neighborhood jointly provide complete services. We employ localized certification schemes to enable ubiquitous services. We also update the secret shares to further enhance robustness against break-ins. Both simulations and implementation confirm the effectiveness of our design.
16579446
Mining Correlation between Motifs and Gene Expression
One of the major challenges in the post-genomic era is to determine all DNA-binding transcription factors (TFs) and their regulatory binding sites (motifs) within the genomes. To discover the relationship between the motifs and changes in gene expression, we propose a new algorithm, co-miner (correlation miner). Correlation rules are generated based on the expression profiles of genes with significant expression change through the time course of gene expression. Thus, we may consider the change in gene expression to be causatively associated with the transcription binding sites in the upstream sequences. In addition, we introduce partition and constraint pushing techniques to improve the performance and demonstrate their effectiveness by our experiments. By applying co-miner to a yeast dataset, the relationships between motifs and gene expression revealed by co-miner are confirmed in the literature.
14349319
Querying XML Documents from a Relational Database in the Presence of DTDs
Many researchers have investigated the problem of storing and querying XML documents using an RDBMS Two situations are considered in this approach based on whether or not an XML schema is available In a schema-oblivious relational approach, an XML schema is not available, or it is available but is not used The advantage of schema-oblivious relational approach is that no XML schema is required, and the fixed generic schema can be used to store XML documents with arbitrary structure However, since XML schema is not exploited, this approach usually implies a query engine where join operations dominate the query time and performance might suffer significantly On the other hand, rare work on the problem of schema-based XML-to-SQL query mapping has been published in the literature In this paper, we present an algorithm to address this problem.
96635
IPv4 address allocation and the BGP routing table evolution
The IP address consumption and the global routing table size are two of the vital parameters of the Internet growth. In this paper we quantitatively characterize the IPv4 address allocations made over the past six years and the global BGP routing table size changes during the same period of time. About 63,000 address blocks have been allocated since the beginning of the Internet, of which about 18,000 address blocks were allocated during our study period, from November 1997 to August 2004. Among these 18,000 allocations, 90% of them started being announced into the BGP routing table within 75 days after the allocation, while 8% of them has not been used up to now. Among all the address blocks that have ever been used, 45% of them were split into fragments smaller than the original allocated blocks; without these fragementations, the current BGP table would have been about half of its current size. Furthermore, we found that the evolution of BGP routing table consists of both the appearance of new prefixes and the disappearance of old prefixes. While the change of the BGP routing table size only reflects the combined results of the two processes, the dynamics of either process is much higher than that of the BGP table size. Finally, we classify routing prefixes into covering and covered ones, and examine their evolution separately. For the covered prefixes, which account for almost half of the BGP table size, we infer their practical motives such as multihoming, load balancing, and traffic engineering, etc., via a classification method.
14239575
Semantics based verification and synthesis of BPEL4WS abstract processes
We introduce a logic model to formally specify the semantics of workflows and their composite tasks described as BPEL4WS abstract processes. Based on the model, we present a set of inference rules to deduce the strongest postcondition and weakest precondition of a workflow and demonstrate that automatic workflow verification is possible due to the restrictions on data manipulation in an abstract process. We then sketch an algorithm that automatically synthesizes a workflow given its specification and a task library.