Alfonso F. Cardenas

Analysis and performance of inverted data base structures

The need to envision and architecture data base systems in a hierarchical level by level framework is stressed. The inverted data base (file) organization is then analyzed, considering implementation oriented aspects. The inverted directory is viewed realistically as another large data base which itself is subjected to inversion. Formulations are derived to estimate average access time (read only) and storage requirements, formalizing the interaction of data base content characteristics, logical complexity of queries, and machine timing and blocking specifications identified as having a first-order effect on performance. The formulations presented are necessary to be used in conjunction with any index selection criteria to determine the optimum set of index keys.

Knowledge-based image retrieval with spatial and temporal constructs

A knowledge-based approach to retrieve medical images by feature and content with spatial and temporal constructs is developed. Selected objects of interest in an image are segmented and contours are generated. Features and content are extracted and stored in a database. Knowledge about image features can be expressed as a type abstraction hierarchy (TAH), the high-level nodes of which represent the most general concepts. Traversing TAH nodes allows approximate matching by feature and content if an exact match is not available. TAHs can be generated automatically by clustering algorithms based on feature values in the databases and hence are scalable to large collections of image features. Since TAHs are generated based on user classes and applications, they are context- and user-sensitive. A knowledge-based semantic image model is proposed to represent the various aspects of an image objects characteristics. The model provides a mechanism for accessing and processing spatial, evolutionary and temporal queries. A knowledge-based spatial temporal query language (KSTL) has been developed that extends ODMGs OQL and supports approximate matching of features and content, conceptual terms and temporal logic predicates. Further, a visual query language has been developed that accepts point-click-and-drag visual iconic input on the screen that is then translated into KSTL. User models are introduced to provide default parameter values for specifying query conditions. We have implemented the KMeD (Knowledge-based Medical Database) system using these concepts.

PICQUERY: a high level query language for pictorial database management

A reasonably comprehensive set of data accessing and manipulation operations that should be supported by a generalized pictorial database management system (PDBMS) is proposed. A corresponding high-level query language, PICQUERY, is presented and illustrated through examples. PICQUERY has been designed with a flavor similar to QBE as the highly nonprocedural and conservational language for the pictorial database management system PICDMS. PICQUERY and a relational QBE-like language would form the language by which a user could access conventional relational databases and at the same time pictorial databases managed by PICDMS or other robust PDBMS. This language interface is part of an architecture aimed toward data heterogeneity transparency over pictorial and nonpictorial databases. >

The knowledge-based object-oriented PICQUERY/sup +/ language

PICQUERY/sup +/, a high-level domain-independent query language for pictorial and alphanumeric database management, is introduced. The PICQUERY/sup +/ language and its underlying stacked image data model are enhanced with major advances that include: convenient specification of the data domain space among a multimedia database federation, visualization of underlying data models, knowledge-based hierarchies, and domain rules, understanding of high-level abstract data types, ability to perform data object matches based on imprecise or fuzzy descriptors, imprecise relational correlators, and temporal and object evolutionary events, specification of alphanumeric and image processing algorithms on data, and specification of alphanumeric and image visualization methods for user presentation. The power of PICQUERY/sup +/ is illustrated using examples drawn from the medical imaging domain. A graphical menu-driven user interface is demonstrated for this domain as an example of the menu interface capabilities of PICQUERY/sup +/. >

Evaluation and selection of file organization—a model and system

This work first discusses the factors that affect file (data base) organization performance, an elusive subject, and then presents a methodology, a model and a programmed system to estimate primarily total storage costs and average access time of several file organizations, given a specific data base, query characterization and device-related specifications. Based on these estimates, an appropriate file structure may be selected for the specific situation. The system is a convenient tool to study file structures and to facilitate as much as possible the process of data base structure design and evaluation.

KMeD: a knowledge-based multimedia medical distributed database system

Abstract The objectives of the Knowledge-Based Multimedia Medical Distributed Database System (KMeD) are to: query medical multimedia distributed databases by both image content and alphanumeric content; model the temporal, spatial, and evolutionary nature of medical objects; formulate queries using conceptual and imprecise medical terms and support cooperative processing; develop a domain-independent, high-level query language and a medical domain user interface to support KMeD functionality; and provide analysis and presentation methods for visualization of knowledge and data models. Using rules derived from application and domain knowledge, approximate and conceptual queries may be answered. These concepts are validated in a testbed linked with radiology image databases. The joint research between the UCLA Computer Science Department and the School of Medicine assures that the prototype system is of direct interest to medical research and practice. The results of this research are extensible to other multimedia database applications.

A unified data model for representing multimedia, timeline, and simulation data

This paper describes a unified data model that represents multimedia, timeline, and simulation data utilizing a single set of related data modeling constructs. A uniform model for multimedia types structures image, sound, video, and long text data in a consistent way, giving multimedia schemas and queries a degree of data independence even for these complex data types. Information that possesses an intrinsic temporal element can all be represented using a construct called a stream. Streams can be aggregated into parallel multistreams, thus providing a structure for viewing multiple sets of time-based information. The unified stream construct permits real-time measurements, numerical simulation data, and visualizations of that data to be aggregated and manipulated using the same set of operators. Prototypes based on the model have been implemented for two medical application domains: thoracic oncology and thermal ablation therapy of brain tumors. Sample schemas, queries, and screenshots from these domains are provided. Finally, a set of examples is included for an accompanying visual query language discussed in detail in another document.

Database Structure and Manipulation Capabilities of a Picture Database Management System (PICDMS)

The database structure and data manipulation capabilities of a generalized PICture Database Management System (PICDMS) are presented. They are based on a dynamic, stacked-image, logical database structure that uses gridded, rather than topological, data representation. A prototype PICDMS has been designed and implemented. A commercial version is being used as a generator of image processing programs. The system has novel capabilities for nonprogrammer users: it is able to 1) build multiple-variable databases from photographs and other two-dimensional data sources such as maps, drawings, etc., and 2) manipulate such data using simple logical commands. Physical organization and accessing strategies are outlined. A summary of the PICDMS data manipulation capabilities is presented and a subset of operations is illustrated with brief examples. A comprehensive example displays PICDMS capabilities and the programming advantages it possesses over other approaches.

Manipulating Data Structures in Pictorial Information Systems

Spatial data handling systems generally use either topological or grid image data structures. It makes little sense for these systems to be incompatible.

PDEL—a language for partial differential equations

Conventional computer methods available to solve continuous system problems characterized by partial differential equations are very time-consuming and cumbersome. A convenient, easy to learn and to use, high level problem oriented language to solve and study partial differential equation problems has been designed; a practical translator for the language has also been designed, and a working version of it has been constructed for a significant portion of the language. This <italic>P</italic>artial <italic>D</italic>ifferential <italic>E</italic>quation <italic>L</italic>anguage, PDEL, is outlined, and the highlights of the translator are briefly summarized.