Search results for "programming."

2020

Abstract Interest in studying information systems discontinuance has been increasing lately, yet there is no consensus on what it means. To improve the situation, we conduct a comprehensive review of current literature on IS discontinuance and identify 55 studies published during 1991–2017 that specifically focus on the topic. Our conceptual analysis disentangles the process, content, and context of the phenomenon, revealing that over the course of a typical IS lifecycle, IS discontinuance may materialize at least in five distinct forms: rejection, regressive discontinuance, quitting, temporary discontinuance, and replacement. After elaborating their distinctions, we discuss their theoretic…

The visual query language CQL for transitive and relational computation

2000

Abstract Classification query language (CQL) is a high-level visual query language with a great expressive power. In CQL the processing of ordinary relations and classifications based on transitive relationships is integrated seamlessly. Relations and classifications are represented in the visual interface in a uniform way through relation and classification skeletons. All query formulation in CQL is QBE-like – based on the intuitive way of filling constants and sample values into the skeletons. In order to guarantee great expressive power, relational and classification expressions can be nested freely with each other at unlimited nesting levels. Recursive definition of transitive processin…

PASSIM – an open source software system for managing information in biomedical studies

2007

Abstract Background One of the crucial aspects of day-to-day laboratory information management is collection, storage and retrieval of information about research subjects and biomedical samples. An efficient link between sample data and experiment results is absolutely imperative for a successful outcome of a biomedical study. Currently available software solutions are largely limited to large-scale, expensive commercial Laboratory Information Management Systems (LIMS). Acquiring such LIMS indeed can bring laboratory information management to a higher level, but often implies sufficient investment of time, effort and funds, which are not always available. There is a clear need for lightweig…

Multiple UAV cooperative path planning via neuro-dynamic programming

2004

In this paper, a team of n unmanned air-vehicles (UAVs) in cooperative path planning is given the task of reaching the assigned target while i) avoiding threat zones ii) synchronizing minimum time arrivals on the target, and iii) ensuring arrivals coming from different directions. We highlight three main contributions. First we develop a novel hybrid model and suit it to the problem at hand. Second, we design consensus protocols for the management of information. Third, we synthesize local predictive controllers through a distributed, scalable and suboptimal neuro-dynamic programming (NDP) algorithm.

Flexible pattern discovery with (extended) disjunctive logic programming

2005

The post-genomic era showed up a wide range of new challenging issues for the areas of knowledge discovery and intelligent information management. Among them, the discovery of complex pattern repetitions in string databases plays an important role, specifically in those contexts where even what are to be considered the interesting pattern classes is unknown. This paper provides a contribution in this precise setting, proposing a novel approach, based on disjunctive logic programming extended with several advanced features, for discovering interesting pattern classes from a given data set.

Errors and Complications in SQL Query Formulation

2018

SQL is taught in almost all university level database courses, yet SQL has received relatively little attention in educational research. In this study, we present a database management system independent categorization of SQL query errors that students make in an introductory database course. We base the categorization on previous literature, present a class of logical errors that has not been studied in detail, and review and complement these findings by analyzing over 33,000 SQL queries submitted by students. Our analysis verifies error findings presented in previous literature and reveals new types of errors, namely logical errors recurring in similar manners among different students. We…

Towards a Better Understanding of the Dynamics of Platform as a Service Business Models

2014

Platform as a Service (PaaS) solutions are changing the way software is produced, distributed, used, and priced. However, there has been little research into understanding the dynamics of PaaS business models and how these business models should be designed to establish a flourishing ecosystem around these platforms. Using design science research (DSR) we first identified the main design elements of PaaS business models as well as their relationships by investigating 24 PaaS providers. The resulting classification scheme as well as the qualitative systems dynamics model (in form of a causal loop diagram (CLD)) facilitates a better understanding of the adoption dynamics of PaaS business mode…

Computing Platform for Virtual Economic Activities Index

2018

The authors enter three economic activity indices, which are calculated from the data in the virtual space on basis of Mobile Operator Call Description Records, Internet Log Files and News Portal audience textual comments and remarks analysis. The article provides the computing facility and the software specification for the Big Data computational platform. Indicates the need to comply this platform with strategy of data privacy requirements solutions and the visualization of results with data geographical mapping.

Schema-Based Visual Queries over Linked Data Endpoints

2019

We present the option to use the schema-based visual query tool ViziQuer over realistic Linked Data endpoints. We describe the tool meta-schema structure and the means for the endpoint schema retrieval both from an OWL ontology and from a SPARQL endpoint. We report on a store of the endpoint-specific schemas and the options to support the schema presentation to the end-user both as a class tree within the environment and as external visual diagram.

Export of Relational Databases to RDF Databases: A Case Study

2010

The vast amount of business information nowadays is stored in relational databases. For the Semantic Web vision to become a reality, we need ways how to exploit this data in form of RDF triples. The universal and commonly accepted solution for this problem still does not exist. In most cases, mapping languages are used for specification of correspondences between OWL ontology and DB schema. At the same time, these languages generally are not well suited for specification of mappings in cases when there is a substantial difference between OWL ontology and DB schema. In this paper, we describe a new model transformation-based method for specification of correspondences between the elements of…