0000000000073864

AUTHOR

Janis Barzdins

How to Comprehend Large and Complicated Systems

The basic problem at early analysis stage of the development life cycle is how to quickly comprehend a large and complicated system. One of the ways to comprehend such a system is to build an object model, as it was suggested by the pioneers of object modelling approach such as J.Rumbaugh1 and J.Martin2. In up-to-date terminology it means building a UML class diagram. The authors have got convinced in their everyday practice on extreme efficiency of this type of modelling, though at the same time a significant experience for this job is also required. To make this job easier, a modelling methodology must be developed. The goal of this paper is, on the one hand, to give some methodological r…

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Pini Language and PiniTree Ontology Editor: Annotation and Verbalisation for Atomised Journalism

We present a new ontology language Pini and the PiniTree ontology editor supporting it. Despite Pini language bearing lot of similarities with RDF, UML class diagrams, Property Graphs and their frontends like Google Knowledge Graph and Protege, it is a more expressive language enabling FrameNet-style natural language annotation for Atomised journalism use case.

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Metamodel specialization based DSL for DL lifecycle data management

A new Domain Specific Language (DSL) based approach to Deep Learning (DL) lifecycle data management (LDM) is presented: a very simple but universal DL LDM tool, still usable in practice (called Core tool); and an advanced extension mechanism, that converts the Core tool into a DSL tool building framework for DL LDM tasks. The method used is based on the metamodel specialisation approach for DSL modeling tools introduced by authors.

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Self-service Ad-hoc Querying Using Controlled Natural Language

The ad-hoc querying process is slow and error prone due to inability of business experts of accessing data directly without involving IT experts. The problem lies in complexity of means used to query data. We propose a new natural language- and semistar ontology-based ad-hoc querying approach which lowers the steep learning curve required to be able to query data. The proposed approach would significantly shorten the time needed to master the ad-hoc querying and to gain the direct access to data by business experts, thus facilitating the decision making process in enterprises, government institutions and other organizations.

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Export of Relational Databases to RDF Databases: A Case Study

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…

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Towards efficient inductive synthesis of expressions from input/output examples

Our goal through several years has been the development of efficient search algorithm for inductive inference of expressions using only input/output examples. The idea is to avoid exhaustive search by means of taking full advantage of semantic equality of many considered expressions. This might be the way that people avoid too big search when finding proof strategies for theorems, etc. As a formal model for the development of the method we use arithmetic expressions over the domain of natural numbers. A new approach for using weights associated with the functional symbols for restricting search space is considered. This allows adding constraints like the frequency of particular symbols in t…

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Model transformation language MOLA

The paper describes a new graphical model transformation language MOLA. The basic idea of MOLA is to merge traditional structured programming as a control structure with pattern-based transformation rules. The key language element is a graphical loop concept. The main goal of MOLA is to describe model transformations in a natural and easy readable way.

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Using Attribute Grammars for Description of Inductive Inference Search Space

The problem of practically feasible inductive inference of functions or other objects that can be described by means of an attribute grammar is studied in this paper. In our approach based on attribute grammars various kinds of knowledge about the object to be found can be encoded, ranging from usual input/output examples to assumptions about unknown object's syntactic structure to some dynamic object's properties. We present theoretical results as well as describe the architecture of a practical inductive synthesis system based on theoretical findings.

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Incorporating hypothetical knowledge into the process of inductive synthesis

The problem of inductive inference of functions from hypothetical knowledge is investigated in this paper. This type of inductive inference could be regarded as a generalization of synthesis from examples that can be directed not only by input/output examples but also by knowledge of, e. g., functional description's syntactic structure or assumptions about the process of function evaluation. We show that synthesis of this kind is possible by efficiently enumerating the hypothesis space and illustrate it with several examples.

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Learning formulae from elementary facts

Since the seminal paper by E.M. Gold [Gol67] the computational learning theory community has been presuming that the main problem in the learning theory on the recursion-theoretical level is to restore a grammar from samples of language or a program from its sample computations. However scientists in physics and biology have become accustomed to looking for interesting assertions rather than for a universal theory explaining everything.

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Towards a theory of inductive inference

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Databases and Information Systems

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Towards Integrated Computer Aided Systems and Software Engineering Tool for Information Systems Design

The paper starts with a brief overview of the current situation in the world of CASE tools for information systems. Then there follows the outline of the basic ideas and principles of integrated CASE tool GRADE. The most outstanding characteristics of GRADE are that the tool is based on a unified specification language GRAPES and that it supports all information system development phases including analysis, requirements specification, design and implementation.

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Inductive inference of recursive functions: complexity bounds

This survey includes principal results on complexity of inductive inference for recursively enumerable classes of total recursive functions. Inductive inference is a process to find an algorithm from sample computations. In the case when the given class of functions is recursively enumerable it is easy to define a natural complexity measure for the inductive inference, namely, the worst-case mindchange number for the first n functions in the given class. Surely, the complexity depends not only on the class, but also on the numbering, i.e. which function is the first, which one is the second, etc. It turns out that, if the result of inference is Goedel number, then complexity of inference ma…

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Modeling and Query Language for Hospitals

So far the traditional process modeling languages have found a limited use in the hospital settings. One of the reasons behind this delay has been the lack of clear definition of the sequence of activities that are carried out in the hospital. We propose a new modeling language (as a profile of UML Class diagrams) that captures all the useful features from various UML diagrams and can be used in modeling of the hospitals. Based on the modeling language, we have developed an easy-to-perceive graphical query language, which allows the physicians to retrieve directly from the various hospital databases information they need to better understand the flow of clinical processes.

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Graphical modeling and query language for hospitals

Abstract Background So far there has been little evidence that implementation of the health information technologies (HIT) is leading to health care cost savings. One of the reasons for this lack of impact by the HIT likely lies in the complexity of the business process ownership in the hospitals. The goal of our research is to develop a business model-based method for hospital use which would allow doctors to retrieve directly the ad-hoc information from various hospital databases. Methods We have developed a special domain-specific process modelling language called the MedMod. Formally, we define the MedMod language as a profile on UML Class diagrams, but we also demonstrate it on example…

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Towards Axiomatic Basis of Inductive Inference

The language for the formulation of the interesting statements is, of course, most important. We use first order predicate logic. Our main achievement in this paper is an axiom system which we believe to be more powerful than any other natural general purpose discovery axiom system. We prove soundness of this axiom system in this paper. Additionally we prove that if we remove some of the requirements used in our axiom system, the system becomes not sound. We characterize the complexity of the quantifier prefix which guaranties provability of a true formula via our system. We prove also that if a true formula contains only monadic predicates, our axiom system is capable to prove this formula…

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Metamodel specialization for graphical modeling language support

Most of current modeling languages are based on graphical diagrams. The concrete graphical syntax of these languages typically is defined informally -- by text and diagram examples. Only recently, starting from UML 2.5, a formalism is offered for defining the graphical syntax of UML. This formalism is based on Diagram Definition standard by OMG, where the main emphasis is on enabling diagram interchange between different tools implementing the given language. While this is crucial for standardized languages such as UML, this aspect is not so important for domain specific languages. In this paper an approach is offered for simple direct definition of concrete graphical syntax by means of met…

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Editor Definition Language and Its Implementation

Universal graphical editor definition language based on logical metamodel extended by presentation classes is proposed. Implementation principles of this language, based on Graphical Diagramming Engine are described.

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Towards DSL for DL Lifecycle Data Management

A new method based on Domain Specific Language (DSL) approach to Deep Learning (DL) lifecycle data management tool support is presented: a very simple DL lifecycle data management tool, which however is usable in practice (it will be called Core tool) and a very advanced extension mechanism which in fact converts the Core tool into domain specific tool (DSL tool) building framework for DL lifecycle data management tasks. The extension mechanism will be based on the metamodel specialization approach to DSL modeling tools introduced by authors. The main idea of metamodel specialization is that we, at first, define the Universal Metamodel (UMM) for a domain and then for each use case define a …

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Towards efficient inductive synthesis: Rapid construction of local regularities

Given several input/output examples of some function we can state the problem: what is the “simplest” function which complies with these examples. This problem is well studied and is known to be very hard in the general case. In this paper we address a special case of the problem, when the target function can be expressed as a simple composition of known functions. We propose a new inductive synthesis algorithm for this case and show that it is efficient enough to synthesize complex geometry formulas.

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Metamodel Specialization for DSL Tool Building

Most of domain-specific tool building and especially diagram editor building nowadays involves some usage of metamodels. However normally the metamodel alone is not sufficient to define an editor. Frequently the metamodel just defines the abstract syntax of the domain, mappings or transformations are required to define the editor. Another approach [8] is based on a fixed type metamodel, there an editor definition consists of an instance of this metamodel to be executed by an engine. However there typically a number of functionality extensions in a transformation language is required. The paper offers a new approach based on metamodel specialization. First the metamodel specialization based …

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OWL Orthogonal Extension

It is critical for knowledge bases to capture the reality in direct and intuitive way. OWL ontology language was designed for this goal. In this paper we study the limitations of the OWL open world semantics for the task of knowledge capture and retrieval. We propose a new mechanism based on the closed world semantics that alleviates part of the limitations. Further we describe a system where both OWL and the new mechanisms interoperate together. Finally, we outline some immediate applications and further research directions.

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Model Transformation Languages and Their Implementation by Bootstrapping Method

In this paper a sequence of model transformation languages L0, L1, L2 is defined. The first language L0 is very simple, and for this language it is easy to build an efficient compiler to C++. The next language L1 is an extension of L0, and it contains powerful pattern definition facilities. The last language L2 is of sufficiently high level and can be used for implementation of traditional pattern-based high level model transformation languages, as well as for the development of model transformations directly. For languages L1 and L2 efficient compilers have been built using the bootstrapping method: L1 to L0 in L0, and L2 to L1 in L1. The results confirm the efficiency of model transformat…

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Automatic construction of test sets: Theoretical approach

We consider the problem of automatic construction of complete test set (CTS) from program text. The completeness criterion adopted is C1, i.e., it is necessary to execute all feasible branches of program at least once on the tests of CTS. A simple programming language is introduced with the property that the values used in conditional statements are not arithmetically deformed. For this language the CTS problem is proved to be algorithmically solvable and CTS construction algorithm is obtained. Some generalizations of this language containing counters, stacks or arrays are considered where the CTS problem remains solvable. In conclusion the applications of the obtained results to CTS constr…

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Learning with confidence

Herein we investigate learning in the limit where confidence in the current conjecture accrues with time. Confidence levels are given by rational numbers between 0 and 1. The traditional requirement that for learning in the limit is that a device must converge (in the limit) to a correct answer. We further demand that the associated confidence in the answer (monotonically) approach 1 in the limit. In addition to being a more realistic model of learning, our new notion turns out to be a more powerful as well. In addition, we give precise characterizations of the classes of functions that are learnable in our new model(s).

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From Databases to Ontologies

This chapter introduces the UML profile for OWL as an essential instrument for bridging the gap between the legacy relational databases and OWL ontologies. We address one of the long-standing relational database design problems where initial conceptual model (a semantically clear domain conceptualization ontology) gets “lost” during conversion into the normalized database schema. The problem is that such “loss” makes database inaccessible for direct query by domain experts familiar with the conceptual model only. This problem can be avoided by exporting the database into RDF according to the original conceptual model (OWL ontology) and formulating semantically clear queries in SPARQL over t…

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On speeding up synthesis and prediction of functions

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Inductive inference of recursive functions: Complexity bounds

This survey includes principal results on complexity of inductive inference for recursively enumerable classes of total recursive functions. Inductive inference is a process to find an algorithm from sample computations. In the case when the given class of functions is recursively enumerable it is easy to define a natural complexity measure for the inductive inference, namely, the worst-case mindchange number for the first n functions in the given class. Surely, the complexity depends not only on the class, but also on the numbering, i.e. which function is the first, which one is the second, etc. It turns out that, if the result of inference is Goedel number, then complexity of inference ma…

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