Expert Systems
Cross-Lingual Knowledge Validation Based Taxonomy Derivation from Heterogeneous Online Wikis
Wang, Zhigang (Tsinghua University) | Li, Juanzi (Tsinghua University) | Li, Shuangjie (Tsinghua University) | Li, Mingyang (Tsinghua University) | Tang, Jie (Tsinghua University) | Zhang, Kuo (Sogou Inc.) | Zhang, Kun (Sogou Inc.)
Creating knowledge bases based on the crowd-sourced wikis, like Wikipedia, has attracted significant research interest in the field of intelligent Web. However, the derived taxonomies usually contain many mistakenly imported taxonomic relations due to the difference between the user-generated subsumption relations and the semantic taxonomic relations. Current approaches to solving the problem still suffer the following issues: (i) the heuristic-based methods strongly rely on specific language dependent rules. (ii) the corpus-based methods depend on a large-scale high-quality corpus, which is often unavailable. In this paper, we formulate the cross-lingual taxonomy derivation problem as the problem of cross-lingual taxonomic relation prediction. We investigate different linguistic heuristics and language independent features, and propose a cross-lingual knowledge validation based dynamic adaptive boosting model to iteratively reinforce the performance of taxonomic relation prediction. The proposed approach successfully overcome the above issues, and experiments show that our approach significantly outperforms the designed state-of-the-art comparison methods.
Acquiring Comparative Commonsense Knowledge from the Web
Tandon, Niket (Max Planck Institute for Informatics) | Melo, Gerard de (Tsinghua University) | Weikum, Gerhard (Max Planck Institute for Informatics)
Applications are increasingly expected to make smart decisions based on what humans consider basic commonsense. An often overlooked but essential form of commonsense involves comparisons, e.g. the fact that bears are typically more dangerous than dogs, that tables are heavier than chairs, or that ice is colder than water. In this paper, we first rely on open information extraction methods to obtain large amounts of comparisons from the Web. We then develop a joint optimization model for cleaning and disambiguating this knowledge with respect to WordNet. This model relies on integer linear programming and semantic coherence scores. Experiments show that our model outperforms strong baselines and allows us to obtain a large knowledge base of disambiguated commonsense assertions.
A New Rational Algorithm for View Updating in Relational Databases
Delhibabu, Radhakrishnan, Behrend, Andreas
The dynamics of belief and knowledge is one of the major components of any autonomous system that should be able to incorporate new pieces of information. In order to apply the rationality result of belief dynamics theory to various practical problems, it should be generalized in two respects: first it should allow a certain part of belief to be declared as immutable; and second, the belief state need not be deductively closed. Such a generalization of belief dynamics, referred to as base dynamics, is presented in this paper, along with the concept of a generalized revision algorithm for knowledge bases (Horn or Horn logic with stratified negation). We show that knowledge base dynamics has an interesting connection with kernel change via hitting set and abduction. In this paper, we show how techniques from disjunctive logic programming can be used for efficient (deductive) database updates. The key idea is to transform the given database together with the update request into a disjunctive (datalog) logic program and apply disjunctive techniques (such as minimal model reasoning) to solve the original update problem. The approach extends and integrates standard techniques for efficient query answering and integrity checking. The generation of a hitting set is carried out through a hyper tableaux calculus and magic set that is focused on the goal of minimality. Keyword: AGM, Belief Revision, Knowledge Base Dynamics, Kernel Change, Abduction, Hyber Tableaux, Magic Set, View update, Update Propagation.
XML Matchers: approaches and challenges
Agreste, Santa, De Meo, Pasquale, Ferrara, Emilio, Ursino, Domenico
Schema Matching, i.e. the process of discovering semantic correspondences between concepts adopted in different data source schemas, has been a key topic in Database and Artificial Intelligence research areas for many years. In the past, it was largely investigated especially for classical database models (e.g., E/R schemas, relational databases, etc.). However, in the latest years, the widespread adoption of XML in the most disparate application fields pushed a growing number of researchers to design XML-specific Schema Matching approaches, called XML Matchers, aiming at finding semantic matchings between concepts defined in DTDs and XSDs. XML Matchers do not just take well-known techniques originally designed for other data models and apply them on DTDs/XSDs, but they exploit specific XML features (e.g., the hierarchical structure of a DTD/XSD) to improve the performance of the Schema Matching process. The design of XML Matchers is currently a well-established research area. The main goal of this paper is to provide a detailed description and classification of XML Matchers. We first describe to what extent the specificities of DTDs/XSDs impact on the Schema Matching task. Then we introduce a template, called XML Matcher Template, that describes the main components of an XML Matcher, their role and behavior. We illustrate how each of these components has been implemented in some popular XML Matchers. We consider our XML Matcher Template as the baseline for objectively comparing approaches that, at first glance, might appear as unrelated. The introduction of this template can be useful in the design of future XML Matchers. Finally, we analyze commercial tools implementing XML Matchers and introduce two challenging issues strictly related to this topic, namely XML source clustering and uncertainty management in XML Matchers.
A History of AI Research and Development in Thailand: Three Periods, Three Directions
Kawtrakul, Asanee (Kasetsart University) | Praneetpolgrang, Prasong (Sripatum University)
Thailand, a country of 65 million people, has had an active AI community for almost three decades. Research on Thai language processing and expert systems was then concentrated on at the laboratory. King Mongkut's University of Technology Thonburi also set up its own AI center -- as a The guest editor for this column was loosely affiliated group. Yuen Poovarawan was the pioneer in computer language processing of the Thai language. It is the National Electronics and Computer Technology now expanded to the Center of Excellence, supported Center (NECTEC) put together research development by National Electronics and Computer plans in AIrelated fields, for example, natural Technology Center (NECTEC), and focuses on language processing, expert systems, and merging together two types of technology: knowledge intelligent image processing.
Using Reactive Rules to Guide a Forward-Chaining Planner
Shanahan, Murray (Imperial College London)
This paper presents a planning technique in which a flawed set of reactive rules is used to guide a stochastic forward-chaining search. A planner based on this technique is shown to perform well on Blocks World problems. But the attraction of the technique is not only its high performance as a straight planner, but also its anytime capability. Using a more dynamic domain, the performance of a resource-bounded version of the planner is shown to degrade gracefully as computational resources are reduced.
A Comparison of Knowledge-Based GBFS Enhancements and Knowledge-Free Exploration
Valenzano, Richard Anthony (University of Alberta) | Sturtevant, Nathan R. (University of Denver) | Schaeffer, Jonathan (University of Alberta) | Xie, Fan (University of Alberta)
GBFS-based satisficing planners often augment their search with knowledge-based enhancements such as preferred operators and multiple heuristics. These techniques seek to improve planner performance by making the search more informed. In our work, we will focus on how these enhancements impact coverage and we will use a simple technique called epsilon-greedy node selection to demonstrate that planner coverage can also be improved by introducing knowledge-free random exploration into the search. We then revisit the existing knowledge-based enhancements so as to determine if the knowledge these enhancements employ is offering necessary guidance, or if the impact of this knowledge is to add exploration which can be achieved more simply using randomness. This investigation provides further evidence of the importance of preferred operators and shows that the knowledge added when using an additional heuristic is crucial in certain domains, while not being as effective as random exploration in others. Finally, we demonstrate that random exploration can also improve the coverage of LAMA, a planner which already employs multiple enhancements. This suggests that knowledge-based enhancements need to be compared to appropriate knowledge-free random baselines so as to ensure the importance of the knowledge being used.
GIPO: An Integrated Graphical Tool to Support Knowledge Engineering in AI Planning
Simpson, Ron M. (University of Huddersfield) | McCluskey, T. Lee (University of Huddersfield) | Zhao, Weihong (University of Huddersfield) | Aylett, Ruth S. (University of Salford) | Doniat, Christophe (University of Salford)
We describe a Graphical Interface for Planning with Objects called GIPO that has been built to investigate and support the knowledge engineering process in the building of applied AI planning systems. GIPO embodies an object centred approach to planning domain modelling. There are two reasons for providing knowledge engineering support for AI planning: (i) to apply a planning system to a new domain to test the planning system itself (ii) to tackle the end-user problem for the engineer who might be a domain expert but need not necessarily have a specialist knowledge of AI planning. Our research is primarily aimed at developing a method and tools to meet the requirements of the latter case (ii), although the benefits can also be enjoyed by planning experts.
On the measure of conflicts: A MUS-Decomposition Based Framework
Jabbour, Said, Ma, Yue, Raddaoui, Badran, Sais, Lakhdar, Salhi, Yakoub
Measuring inconsistency is viewed as an important issue related to handling inconsistencies. Good measures are supposed to satisfy a set of rational properties. However, defining sound properties is sometimes problematic. In this paper, we emphasize one such property, named Decomposability, rarely discussed in the literature due to its modeling difficulties. To this end, we propose an independent decomposition which is more intuitive than existing proposals. To analyze inconsistency in a more fine-grained way, we introduce a graph representation of a knowledge base and various MUSdecompositions. One particular MUS-decomposition, named distributable MUS-decomposition leads to an interesting partition of inconsistencies in a knowledge base such that multiple experts can check inconsistencies in parallel, which is impossible under existing measures. Such particular MUSdecomposition results in an inconsistency measure that satisfies a number of desired properties. Moreover, we give an upper bound complexity of the measure that can be computed using 0/1 linear programming or Min Cost Satisfiability problems, and conduct preliminary experiments to show its feasibility.
Knowledge Base of an Expert System Used for Dyslalic Children Therapy
Schipor, Ovidiu-Andrei, Pentiuc, Stefan-Gheorghe, Schipor, Doina-Maria
-- In order to improve children speech therapy, we develop a Fuzzy Expert System based on a speech therapy guide. This guide, write in natural language, was formalized using fuzzy logic paradigm. In this manner we obtain a knowledge base with over 150 rules and 19 linguistic variables. All these researches, including expert system validation, are part of TERAPERS project (financed by the National Agency for Scientific Research, Romania). I. INTRODUCTION The main objectives of speech therapy expert system develop by our team are [1]: - personalized therapy (the therapy must be in according with child's problems level, context and possibilities); - speech therapist assistant (the expert system offer some suggestion regarding what exercises are better for a specific moment and from a specific child); - (self) teaching (when system's conclusion is different that speech therapist's conclusion the last one must have the knowledge base change possibility).