Query Resolution Research Articles

Development of a multicenter interventional cardiology database: the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) experience.

The technical challenges in the development of a quality-controlled registry of percutaneous coronary interventions (PCIs) are currently unknown. This article describes the authors' experience in the development of a regional, quality-controlled PCI registry. In 1996, 16 centers in Michigan were invited to participate in a multicenter PCI registry. Nine centers agreed to a pilot data collection and, as of July 2001, eight centers are still actively collecting data. An Oracle database was developed by the coordinating center. A common data collection form and a standard set of definitions were agreed on during several meetings. Data validity was insured through review of each form by a trained nurse, by automatic database diagnostic routines, and by site visits that included a review of the catheterization laboratory logs and a review of randomly selected charts. The average number of forms requiring query resolution was 33% in 1997 (range 7-76%), and it decreased to 5% in 1999 (range 1.4-10%). The most commonly queried variables were outcomes prior to discharge, lesion category, lesion complexity, date of birth, device used, gender, postprocedural percent stenosis, presence of left main disease, and MI date. Invalid dates, identification of the doctor, the presence of duplicate forms, and of duplicate outcomes were additional common queries generated by the internal diagnostic routines. In conclusion, the number of queries and diagnostic reports generated in the database suggests that the development of a quality-controlled PCI registry requires the institution of a careful diagnostic and data quality assessment system.

Neurological teleconsultation for general practitioners.

A neurology teleconsulting network was implemented between a university hospital in Lisbon and five nearby health centres. PCs equipped for videoconferencing were installed, connected by ISDN lines at 128 kbit/s. Fifty-three general practitioners (GPs) were surveyed. The survey showed that the GPs had difficulties in using computers, but they had definite intentions to use teleconsultation for neurology cases and 83% of the respondents stated that they would probably use the technique. During the study, 90 neurology teleconsultations took place over 55 weeks. The average consultation rate was 1.6 teleconsultations per week (SD 1.3, range 0-6). The conferences lasted 10-45 min. Longer teleconsultations were mainly due to technical difficulties in using computers on the part of users with a low level of computer literacy. The patients were 42 males and 46 females, with a mean age of 38 years (SD 20, range 1-84); two patients were discussed twice. The benefits consisted mainly of advice on patient medication, diagnosis and the prevention of unnecessary specialist consultations or laboratory examinations. Doctor-doctor teleconsultation allows the rapid resolution of queries which otherwise cause stress to patients and increase the cost and complexity of care.

Constructing Multilevel Metadata Networks for Sharing Dispersed and Transient Information in a Mobile Environment

An intelligent multi-user mechanism has been prototyped at the Information System Collaboratory of the Pennsylvania State University, which is capable of resolving global queries with differing and overlapping information needs, spatial scalability and temporal assumptions. The sources of information for this prototype are mechanical damage monitoring sensors embedded in equipment at plant sites, on-board ships or aircrafts, archived historical and diagnostic databases like those available through NALCOMIS (NAVMASSO document J-004 EM-001C, 1995) logistics and maintenance databases at depots, interactive electronic technical manuals stored in databases, dynamic models of damage, and models of operational performance. The concept-of-operation includes mobile access to this information by equipment maintainers on-board ships, aircrafts and other mobile platforms. Real-time interoperation of these system components and databases, under dynamic equipment operating conditions of thermo-mechanical and environmental stress, requires complex interactions of internal representations of sensor data, performance requirements, resources and equipment models, with rich semantics. To support such interactions, following the work of Bright, Hurson and Pakzad (Bright, Hurson, and Pakzad, Transactions on Database Systems, Vol. 19, No. 2, pp. 212–253, 1994) local schema terms of available data sources are organized as the leaf nodes in a semantic network of metadata. The physical nodes of the network are partitioned into a top-down multi-level search control structure of increasing precision and decreasing semantic aggregation. Each physical node supports search through all lower layers of metadata in connected tree configurations. The resulting multilayered semantic network is modeled as a Thesaurus of terms T and relationships R. A relationship in R may be crisp or fuzzy. The DTIC (Defense Technical Information Center) thesaurus for equipment maintenance was used as a starting point in this work. It was further enhanced by application specific terms and endowed with a distance function. This distance function is used to formulate user adaptable Graphic User Interfaces (GUI) for making quality of service tradeoffs in the resolution of global queries. Step-by-step construction of the thesaurus as a multilevel metadata network, its scalability, dynamic adaptation through usage, and tolerance of semantic imprecision in query resolution are discussed in this paper. Furthermore, performance metrology for evaluating quality of service in global query resolution is also developed (Phoha, in Proceedings of the NIST Workshop on Advancing Measurements and Testing for Information Technology, Gaithersburg, MD, Oct. 1998). This work was funded by DARPA for the past four years under grant DE-FC36-94G010064, for establishing a National Information Infrastructure Testbed for Electronic Commerce in equipment health monitoring, failure diagnosis and prognosis services.

Fuzzy temporal constraint logic: a valid resolution principle

In this work we propose a fuzzy temporal constraint logic. First of all, we provide the formal language which will allow the expression of well-formed formulas related to the temporal events by means of temporal constraints. Secondly, we introduce a valid resolution principle in order to solve the queries in this logic. Finally, we will show that this resolution principle is a generalization of the resolution principle proposed for a possibilistic logic with fuzzy predicates (Dubois and Prade, Internat. J. Approx. Reason. 4 (1990) 1–21). All this will serve to reason within a context of the theoretical model of the temporal reasoning proposed by Marı́n and Barro (Fuzzy Temporal Constraint Network, FTCN) (Marı́n et al., Cybernet. Systems 25(2) (1994) 207–215). This model underlies a module for the resolution of temporal queries. This module belongs to a diagnostic and intelligent monitoring system of patients, based on temporal reasoning. The system is applied to the patients admitted in the Intensive Care Units with severe ischemic cardiopathy, submitted to continuous monitoring of the electrical and mechanical signals of the heart. However, what is exposed here in this document is not limited to a field of application in particular, but instead, it is completely general.

A query resolution engine to handle a path operator with multiple paths

An end-user query of a Geographical Information System (GIS) can formally be defined as the application of a set of operators (spatial or not). Geographical Information Systems used for Transportation (GIS-T) must provide a path evaluation operator. For example, an end-user query may involve a selection based on alphanumeric criteria, an evaluation of path, and a spatial intersection. This composition of operators and the fact that the evaluation of a path may not provide a unique result impose the definition of a query resolution model or a database query language able to support this composition. In this paper we present a query resolution model. The use of multi-criteria analysis and the definition of aggregates in a query (nearly mandatory) may involve ambiguities in the final presentation of the results to an end-user. The formal modeling of query results must take into account this risk. The philosophies of a query definition and the presentation of the results may be different (e.g., formular vs visual). The management of query results must take into account the data model associated with the query results, the results themselves (metabase/database), and the interpretation. The interpretation avoids errors due to visual ambiguities of an operator with an aggregate function.

Compressing Integers for Fast File Access

Fast access to files of integers is crucial for the efficient resolution of queries to databases. Integers are the basis of indexes used to resolve queries, for example, in large internet search systems, and numeric data forms a large part of most databases. Disk access costs can be reduced by compression, if the cost of retrieving a compressed representation from disk and the CPU cost of decoding such a representation is less than that of retrieving uncompressed data. In this paper we show experimentally that, for large or small collections, storing integers in a compressed format reduces the time required for either sequential stream access or random access. We compare different approaches to compressing integers, including the Elias gamma and delta codes, Golomb coding, and a variable-byte integer scheme. As a conclusion, we recommend that, for fast access to integers, files be stored compressed.

Massive query resolution for rapid selective dissemination of information

The tasks of choosing documents from a new collection and categorizing the choices, both on the basis of a body of standing queries, are known variously as selection and routing, selective dissemination of information (SDI), and information filtering. The combined operation of selecting and labeling documents naturally separates into two processes: feature scanning and query resolution. The first process examines a document for features and their locations; the second takes the findings from the first process, looks for satisfaction of combinations specified in the queries, and marks the document accordingly. When the body of queries is large, query resolution can become a significant factor in total processing speed. This paper outlines an efficient approach to performing query resolution on massive Boolean queries, suitable for implementation on a desktop computer. Algorithms are sketched in pseudo-code and experimental results are reported.

A Survey of Technologies for Parsing and Indexing Digital Video1

In the future we.envision systems that will provide video information delivery services to customers on a very large scale. These systems must provide customers with mechanisms to select programs of their choice from live broadcasts. Customers should also be provided with easy means of browsing and accessing prerecorded digital data (e.g., distributed digital multimedia libraries), and downloading data from other information sources. To be viable for such large information sets, these systems must understand customer preferences and tailor the available information to the customer's needs. To support this vision, a number of issues must be addressed and obstacles overcome. Intuitive interfaces, powerful query formulation and evaluation techniques, comprehensive data models, and flexible presentation functionalities must be developed. To realize these components, an effective query evaluation engine with the capabilities of query resolution in different content-specific formats (e.g., by graphics, by image, by sound) and in different domain-specific models (e.g., database of movies, database of newsclips) should be present. Additionally, the digital video database will require an efficient indexing system for easy access to the stored information. In this paper we discuss existing research trends in this area and requirements for future data delivery systems. An overview of video indexing is presented followed by a discussion on current indexing techniques.

X.500 Index DSAs and scaling issues for an indexed white pages directory service

This paper introduces the notion of X.500 Index DSAs. These are DSAs which hold indexes to entries held in the distributed X.500 directory. An Index DSA provides a similar enhancement to distributed X.500 to the one that archie provides for FTP. Index DSAs are created to provide specific services that are hard to provide in a fully distributed directory. An Index DSA is not technically different from an ordinary DSA, except that it does not provide references to parts of the DIT it does not hold. A pragmatic difference is that Index DSAs effectively hold pointers to entries, rather than the entries themselves. The paper then examines whether Index DSAs really can solve a critical white pages search problem, which is that if a user is unable to restrict the scope of a query to one organisation, then there is no systematic way of restricting the scope of the query to a small number of servers. The analysis is based on using a sample of past queries made within the UK DIT. The paper examines whether Index DSAs allow us to prune the search space sufficiently to allow efficient country-wide searches. The paper also examines whether there are substantial differences in query resolution effectiveness between using a single Index DSA and using a small set of hierarchically organised Index DSAs.

Knowledge Modularization for Adaptive Decision Modeling

Existing research has shown that theorem proving techniques of predicate calculus can be used as effective tools for query resolution in decision support systems. Implementation of these techniques however require searching large axiom sets leading to dead ends and backtracking. In this paper we use a mathematical programming approach to partition axiom sets into modules for efficient query resolution. The method is based on a two-stage analysis of the domain specific knowledge regarding queries types. The first stage analyzes the queries to determine the information requirement on the axiom set. The second stage determines the optimal modularization of the axiom set using this information. The advantage of our approach is that by selecting the appropriate modules for query resolution only a subset of axioms are considered in the resolution process. This approach works significantly better than the traditional methods when the axiom set can be partitioned into non-overlapping modules based on the commonality of a given query set. In the case of module overlap, the math program assigns the axioms to one of the overlapping modules maximizing overall query resolution efficiency of the system. An adaptive component performs dynamic reorganization of the modules when the query set is time variant. Real time issues of query resolution with modularized axiom set are briefly discussed. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.

The INA: a simple query language with only attribute names

Current query languages, such as SQL, assume that the user is familiar with the database schema including the attribute names, types, and relation associations. When a user has imperfect knowledge of this information (or when he balks at the data-processing orientation of the required statements), he normally asks an experienced analyst to perform his and hoc query. The Intelligent Navigational Assistant (INA) was developed for the U S Army as a prototype query tool that permits the users to specify requests using only domain terms familiar to them. Once a request is made, it is converted into SQL for processing 1,2 To facilitate query formulation, the INA supports an interface that allows the user to identify attributes without relation associations (i.e., treats the data model as a universal relation). Because an attribute may appear in many relations, one of the principal tasks of the INA is the determination of the appropriate relation bindings. To aid in the selection of terms, the INA maintains a user vocabulary and provides facilities for browsing the vocabulary and examining term definitions. Thus, the INA has two primary functions it provides an easy-to-use interface for query definition, and it converts a request into SQL. The INA prototype has been implemented as a PC-resident knowledge-based system linked to a host-based DBMS. Its knowledge base is the logical schema of the target database, and the query transformation relies on the dependencies implicit in that schema. Supporting the knowledge-processing functions are the query definition interface, various tools to manage the target data model description, and facilities for communicating with other computers. The system was developed using TEDIUM@@@@, 3 and the user interface and query resolution mechanism are extensions of earlier work with Tequila 4 (which accessed the semantically-richer TEDIUM@@@@ data model) Work on the INA began in 1987 and was terminated in 1988. The system was demonstrated as a prototype with an Army-supplied logical model consisting of approximately 40 relations and 200 attributes. After query definition, reformation, and user acceptance, the SQL queries were submitted to the mainframe for processing. In those tests, the INA often produced better queries than those manually coded by analysts. The INA currently is undergoing a beta test with a much larger database schema. Its algorithms are described in reference 5, and reference 3 contains details regarding its implementation and semantic data model. Current research includes the development of improved query resolution algorithms based on an enriched semantic data model

Representing modeling knowledge in an intelligent decision support system

Knowledge representation for data, models, and other decision support system (DSS) elements is a complex and ever-adapting task. The representation scheme for an intelligent DSS will need to provide general problem-solving model management activities as well as a mechanism for refining and testing the applicability of these models for each problem instance it encounters. We present traditional knowledge representation alternatives, and demonstrate why a multi-level scheme is superior for DSS use. We advance a two-level scheme, joining the advantages of connection graphs for the generalized analytical requirements and a frame component for problem-specific query resolution.

A microprogrammed search controller for a text scanning processor

The objective of the research in this paper is the design of a non-numeric processor to be used in the scanning of textual information brought in from serial storage. Source text progresses through a linear array of 32 cells each cell capable of holding one character. With all cells operating in parallel, character subsequences in the source stream can be compared with character strings in any one of 16 registers associated with the cellular array. Various modules associated with the array are used to aid the query resolution process. The overall design emphasizes speed of execution and versatility of operation.

The Baptist Western Association 1653–1658

The identification of a tract without title-page or caption title in the Library of the Society of Friends in London, together with the location in the Library of the Baptist College, Bristol, of another tract of which no copy was known to exist, makes it possible for the first time to summarise fully the beginnings of the Baptist Western Association. The Association's activity, apart from days spent in waiting upon God in fasting and prayer, was twofold: the resolution of queries submitted by the churches represented; and the issuing of circular letters of exhortation to the churches. Circular letters issued from nine of the Association's first ten meetings are printed in the first of the tracts mentioned, queries submitted and resolved at nine of the meetings in the second. From other sources we know that in 1655 the Association ordained as its superintendent Thomas Collier, the editor of both tracts; and that in 1656 it issued aConfession of the Faith. An assembly of ‘messengers’ or representatives of churches in the South-Western counties of England, meeting normally once in the spring and once in the autumn, the Western Association was a pioneer among those regional associations of churches which have ‘always been a feature of Baptist life’. Correct information concerning its meetings and leaders, and the churches represented, is thus desirable. The fifty-seven queries, moreover, with the answers they received, throw light upon issues then the concern of many beyond Baptist circles.