This paper proposes a cooperative query answering approach that relaxes query conditions to provide approximate answers by utilizing similarity relationships between data values. The proposed fuzzy abstraction hierarchy (FAH) represents a similarity relationship based on the integrated notion of data abstraction and fuzzy relations. Based on FAH, the authors develop query relaxation operators like query generalization, approximation, and specialization of a value. Compared with existing approaches, FAH supports more effective information retrieval by processing various kinds of cooperative queries through elaborate relaxation control and providing ranked query results according to fitness scores. Moreover, FAH reduces maintenance cost by decreasing the number of similarity relationships to be managed.

User profile data (for example, age and sex) is usually self-reported by users, so it is prone to human errors or biases. For example, a user can be reluctant to provide a company with private information such as his/her actual age upon subscription, thus the user either does not fill in the age column or put in some random numbers to avoid unwanted privacy intrusion. However, inaccurate or uncertain user profile data undermines the integrity of a company's marketing or operational intelligence. Targeting customers based on uncertain user profile data will not be as effective as targeting customers based on accurate user profile data. Thus companies perform preprocessing on user profile data as part of effort to maintain the accuracy of their user profile data. This paper presents a study of preprocessing uncertain user profile data based on a proposed simple collaborative learning algorithm. We demonstrate that a user's accurate profile information can be inferred from profile information of the user's social network neighbors. Particularly, we address the issue of how a communication service company can verify whether a user's reported age is true or not. We implement a simple collaborative learning algorithm using mobile network data. The dataset contains anonymized user data from a large Korean mobile company, capturing 174,071 users' demographic profiles and their communication histories. To construct a mobile social network among users, we collect 3G voice call histories including 561,787 unique call receivers who belong to the same service carrier. Results reveal that the prediction accuracy of the proposed method based on voice network data is 97% which is very high compared to 53%, the best accuracy by among competing methods and indicates that our method effectively detects users with great discrepancy between self-reported age and actual age.

Query relaxation is one of the crucial components for approximate query answering. Query relaxation has extensively been investigated in terms of categorical data; few studies, however, have been effectively established for both numerical and categorical data. In this article, we develop a query relaxation method by exploiting hierarchical quantified data abstraction, and a novel method is proposed to quantify the semantic distances between the categorical data so that the query conditions for categorical data are effectively relaxed. We additionally introduce query relaxation algorithms to modify the approximate queries into ordinary queries, which are followed by a series of examples to represent the modification process. Our method outperformed the conventional approaches for the various combinations of complex queries with respect to the cost model and the number of child nodes.

In knowledge management systems (KMS), managing explicit knowledge is comparatively easy using in-formation technology such as databases. However, tacit knowledge, usually possessed by human experts in unstructured forms such as know-how and experiences, is hard to systemize. Recent research has shown that it is more effective to provide search mechanisms for experts than to directly search for specific knowledge itself in KMS to pinpoint experts with needed knowledge in the organizations so that users can acquire the knowledge from the found experts. In this article, we propose an intelligent search framework to provide search capabilities for experts who not only match search conditions exactly but also belong to the similar or related subject fields according to the user’s needs. In enabling intelligent searches for experts, the Fuzzy Abstraction Hierarchy (FAH) framework has been adopted. Based on FAH, searching for experts with similar or related expertise is facilitated using the subject field hierarchy defined in the system. While adopting FAH, a text categorization approach based on Vector Space Model is also utilized to overcome the limitation of the original FAH framework. To test applicability and practicality of the proposed framework, the prototype system, “Knowledge Portal for Researchers in Science and Technology” sponsored by the Ministry of Science and Technology (MOST) of Korea, has been developed.

Process information sharing is a beneficial tool through which participating organizations in a virtual enterprise can improve their customer services and business performance. However, autonomy and agility of the organizations have placed limitations in the development of process information sharing, which the previous research has not satisfactorily addressed. This paper proposes a federated process framework and its system architecture that provide a conceptual design for effective implementation of process information sharing supporting the autonomy and agility of the organizations. First, in terms of autonomy, the federated process framework supports a flexible sharing policy to control the amount of shared data so that the framework can be applied to a wide variety of practical situations from loosely-coupled cases to tightly-coupled cases. Second, in terms of agility, the system architecture based on the federated process framework supports the entire life cycle of process information sharing by allowing sufficient adaptability to the changes of business environments. We develop the framework using an object-oriented database and Extensible Markup Language to accommodate all the constructs and their interactions within object-oriented message exchange model.

As database users adopt a query language to obtain information from a database, a more intelligent query answering system is increasingly needed. Relational databases are exact in nature, but effectiveness of decision support would improve significantly if the query answering system returns approximate answers rather than a null information response when there is no matching data available. This paper proposes an abstraction hierarchy as a framework to practically derive such approximate answers from ordinary everyday databases. It provides a knowledge abstraction database to facilitate the approximate query answering. The knowledge abstraction database specifically adopts an abstraction approach to extract semantic data relationships from the underlying database, and uses a multi-level hierarchy for coupling multiple levels of abstraction knowledge and data values. In cooperation with the underlying database, the knowledge abstraction database allows the relaxation of query conditions so that the original query scope can be broadened and thus information approximate to exact answers can be obtained. Conceptually abstract queries can also be posed to provide a less rigid query interface. A prototype system has been implemented at KAIST and is being tested with a personnel database system to demonstrate the usefulness and practicality of the knowledge abstraction database in ordinary database systems.