Girts Karnitis

Intelligent integration of information from semistructured web data sources on the basis of ontology and meta-models

As computer users face an increasing amount of various semi-structured information sources, the issue of correlating, integration and presenting related information to users becomes all the more important. As a solution, we propose the semi-structured data universal data browser, which, in its operations, makes use of descriptions of data sources that are presented in the form of meta-models or ontologies, ensuring the users ability to use information from the data sources. Information from semi-structured data sources is analyzed, transformed and stored in the semi-structured data universal data browser database, which is based on meta-models. The ontologies of information in each data source are preserved, and they are mutually linked to logical and global ontologies through the use of mapping. As an example, we use the integration of information on Internet homepages about products and their classifications

Heterogeneous database browsing in WWW based on meta model of data sources

This paper describes a development principle and technique for a simple universal multiple database browser. The browser operates by getting information from metamodel of data sources and actual data from legacy data sources. Every element such as entity, field, and relation is mapped to some component of HTML page with appropriate structure and layout. Many templates of information layouts can be created allowing to dynamical changing of HTML page to acceptable user interface. The wrappers are used to provide browser with actual data and to act as mediators between data sources and browser. This approach allows to quickly describing new data sources, creating wrappers, making modifications later and managing data browsing in a simple unified style. The browser architecture is flexible enough to incorporate data sources with a variety of data models and query capabilities by various protocols. It is possible to select logically tied information from all available legacy data sources.

Models of Event Driven Systems

This paper provides the business process modeling approach based on usage of Domain Specific Languages (DSL). The proposed approach allows us to create executable information systems’ models and extends the concept of Event Driven Architecture (EDA) with the business process execution description. It lets us apply principles of the Model Driven Development (MDD) in order to create the information system which complies with the model. The proposed approach provides a set of advantages in information systems development, use and maintenance: bridges the gap between business and IT, an exact specification, which is easily to implement into information system, up-to-date documentation etc. The practical experience proves the viability of the proposed approach.

Semantics for Managing Systems in Heterogeneous and Distributed Environment

The problem of legacy systems collaboration is being solved. Particularly we look at the collaboration as workflow in a distributed and heterogeneous environment. Attention is paid to the description of semantics for workflow process definition languages. There are many solutions how semantics can be decomposed into logical fragments, but the problem of obtaining reusable components that are easy to compile into desired specific semantics still remains. We evolve the division of semantics by semantic aspects whose description is based on abstract data types (pre-built components) and connectors (meta-programs to produce the glue code) between them. This paper offers a way in which semantic aspects are linked with the intermediate representation of a program, and performing of semantics is provided. We mix together various semantics aspects to get a desirable semantics.

Modelling of Adequate Costs of Utilities Services

The paper propose methodology for benchmark modelling of adequate costs of utilities services, which is based on the data analysis of the factual cases (key performance indicators of utilities as the predictors). The proposed methodology was tested by modelling of Latvian water utilities with three tools: (1) a classical version of the multi-layer perceptron with error back-propagation training algorithm was sharpened up with task-specific monotony tests, (2) the fitting of the generalized additive model using the programming language R ensured the opportunity to evaluate the statistical significance and confidence bands of predictors, (3) the sequential iterative nonlinear regression process with minimizing mean squared error provided the notion of the impact of each predictor on the searched regularity. The quality of models is high: the adjusted determination coefficient is greater than 0.75, explained deviance exceeds 0.80, while the correlation between the respective modelled values exceeds even 0.95.

Transparent Model for State Management

To ensure optimum governance of the state (regions, sectors, specific activities) all management system units (tasks, functions and services, normative environment, institutional framework, budget funding) have to operate in strong cooperation and consistency, which should be defined by corresponding documents. Unfortunately this logical relevance does not always exist. Documents and information are weakly connected, because of the huge complexity of units that objectively hinders implementation of the strong linkage and seriously weakens management quality. The situation can be radically improved by usage of ontological methodology for development of the back-office of the management system—strict structuring of objects and their decomposition in elementary logical units to form different hierarchies of information. Each hierarchy displays some aspect of information. Connection of related units of the information from different documents (hierarchies) creates a full graph of relevant information; it enables processing and usage of management information in static and dynamic regimes—definition and concretization of normative acts, institutional structure, funding—passage and execution of tasks, etc. Analysis of information from different aspects, checking its consistency, and making appropriate decisions on this base is becoming possible, thus minimizing threats to well-functioning and development of the country. Two case studies illustrate the current usage of the proposed principles. Complexity of the informative model requires appropriate level of IT support. Requirements as well as short descriptions of developed IT tools are included; they are oriented on usage by non-IT specialists (civil servants). Projections of further activities for improvement features of the model and consummation of IT tools are mentioned.