Browsing by Type "proceedings-article"

Now showing 1 - 20 of 69
  • Publication
    A Meta-Model Based Approach to UML Modelling
    (2008)
    Teilāns, Artis 
    ;
    Arnis Kleins
    ;
    Uldis Sukovskis
    ;
    Yury Merkuryev
    ;
    Ivars Meirans
    This paper is devoted to a meta-model based approach to UML systems modelling. The approach allows creating a system model by operating with artefacts from the problem domain, followed by generation of a UML model. The discussed approach is illustrated by generating UML models, using Use Case and Activity diagrams of the UML language.
    Scopus© Citations 5
  • Publication
    A Metamodel Based Approach for UML Notated Domain Specific Modelling Language
    (2011)
    Arnis Kleins
    ;
    Teilāns, Artis 
    ;
    Yuri Merkuryev
    ;
    Ojars Krasts
    This paper focuses on a metamodel based approach to Unified Modelling Language (UML systems modelling and simulation. The approach allows creating a system model by operating with artefacts from the problem domain. As a novelty for UML modelling, especially for simulation purposes, the presented meta-model is enriched by a set of stochastic attributes of modelled activities. Modelling process is ensured by developing UML based Domain Specific Language (DSL) that is suitable for the metamodel, where UML diagrams are complemented with attributes necessary for model simulation. A modelling tool prototype was developed with Microsoft Visual Studio using Microsoft Visualization and Modelling SDK. Elaborated models are stored in a modelbase which conforms to the described metamodel. Relevant DEVS simulation software will be developed for ability to run those models and analyse gathered results. The given approach facilitates increases of the productivity in development of domain specific modelling and simulation tools up to 10 times.
    Scopus© Citations 2
  • Publication
    Air ionizer and indoor plants interaction impact on ion concentration
    (2017)
    Natalija Siņicina
    ;
    Martinovs, Andris 
    The plants emit different types of volatile organic compounds (Bio VOC’s) and can improve air quality: they effectively remove organic pollutions and reduce the number of microorganisms in the air by releasing phytoncides. The lack of negative ions in the air can cause deterioration of the health of humans breathing it. At the same time, an air saturated with negative ions can improve the state of health and provide a comfortable environment. In this article, the influence of the plants (Cupressus macrocarpa) on the number of ions is proved, based on a series of experiments performed with applying high-voltage pulses (air ionizer). This work is devoted to the elaboration of the mathematical relationship between the air ions concentration and the factors influencing it. For this purpose an experimental stand was made, consisting of two equal compartments: one contained the plants while another one was used as a control without plants. It was concluded that the plants, in general, are able to stabilize the ion concentration and to reduce its fluctuations. The plants help to increase the concentration of negative ions and to decrease the concentration of positive ones.
  • Publication
    Analysis of factors affecting zero-waste food consumption in schools
    (2022)
    Deksne, Juta
    ;
    Litavniece, Lienīte
    ;
    Zvaigzne, Anda
    ;
    Lonska, Jeļena 
    ;
    Kodors, Sergejs
    The research aims to identify the factors affecting food waste and waste generation in schools and, consequently, barriers to zero-waste food consumption based on a systematic review of literature for the period 2015-2022. The research employed qualitative methods: systematic literature review, analysis and synthesis, as well as the monographic method. The literature review examined 1702 research papers and the abstracts. Using a PRISMA 2020 flow diagram, 54 papers were selected from the ScienceDirect, Scopus and Google Scholar databases for an in-depth analysis. Based on the literature review, 8 groups of factors that affected the generation of food waste in schools in the consumption process were identified: demographical, political, school food policy, environmental, socio-economic, personal/human, physical/human and geographical. The factors identified and aggregated might provide a basis for further discussions on zero-waste food consumption and food waste reduction in schools, as well as specific actions to optimize school food consumption and promote effective food and food waste management.
  • Publication
    ANALYSIS OF REMIGRATION POLICY IN THE BALTIC STATES
    (2022)
    Iveta Mietule
    ;
    Iluta Arbidane
    ;
    Kristine Sudnika
    ;
    Arvis Arbidans
    ;
    Nikola Elizabete Mietule
    The number of the country's population has significantly decreased in the Baltic States over the last fifteen years, experiencing the highest wave of emigration in the years of the economic crisis, when many residents went to other countries to ensure higher incomes and material well-being in general. In the Baltic States, emigrants are mainly people of working age. This has an impact on the labour market and the national economy as a whole. As the role of the labour force in the formation of the national economy is very high, it is important to make correct and balanced decisions about the measures aimed at returning the labour force to the country, forming the remigration policy. The aim of the study is to analyse the remigration policy in the Baltic States in the context of general migration trends. The current study proposes the following hypothesis - the remigration policy in the Baltic States has been developed according to similar principles and includes a similar set of measure. The following research methods support the study: logicalconstructive method, scientific induction method, statistical data analysis method and graphical data processing method.
  • Publication
    Artificial Neural Networks: What Can They Learn about Color Laser Marking?
    (2018)
    Pavels Cacivkins
    ;
    Lazov, Lyubomir 
    ;
    Teirumnieks, Edmunds 
    ;
    Martins Sperga
    ;
    Ingus Dilevka
    ;
    Artis Vitins
    Color laser marking paves the way for many useful applications in modern industry - traceability, anticounterfeiting, etc. Laser marking of materials is an inherently difficult problem with no clear functional relationship between many technological parameters on the input and the results of processing on the output. Some processes cannot be well defined without the use of examples. In this paper we discuss the novel method of training artificial neural networks using real experimental color laser marking data for prediction of results. We conclude the paper by discussing the other potential applications of proposed solution in the field of laser materials processing.
    Scopus© Citations 1
  • Publication
    ASSESSMENT OF THE STRATEGY OF THE LOCAL ACTION GROUP „PARTNERSHIP OF REZEKNE DISTRICT COMMUNITIES”
    (2015)
    Iveta MIETULE
    ;
    Anda ZVAIGZNE
    The paper is produced based on the authors’ research “Assessment of the Introduction of the Rural Development Programme 2007–2013 Activity “Local Development Strategy” by the Partnership of Rezekne District Communities and Proposals for its Further Development”. Research on the activity of local action groups (LAGs) and their influence on the overall development of regional territories became urgent in recent years, given the implementation of the European programme LEADER. The research object of the paper is a LAG – the Partnership of Rezekne District Communities – that is located in Latvia, Latgale region. The research aim is to assess the strategy of the local action group. The research employed the monographic and descriptive methods as well as analysis, synthesis, the graphic method, data grouping and a sociological research method – a questionnaire survey. A survey of project submitters identified three major fields in which it is planned to submit and implement projects in the next programming period in the LAG’s territory. They are: promotion of active recreation and sports; reconstruction of the territory; and organisation of and contribution to cultural events. The surveyed residents agreed with the following assertions regarding their lifestyle: an enhanced surrounding environment and natural, cultural and other significant historical objects foster tourism; the establishment and functioning of youth centres contribute to useful spending of leisure time by youths and their communication; the availability of sport and fitness equipment and of sports grounds increases local residents’ interest and wish to practise a healthy and physically active lifestyle. Based on the data acquired and the interpretation of findings, proposals were made for the further development of the territory as well as the research methodology was explained for the purpose of carrying out analogues research studies in the future.
  • Publication
    Attitudes toward the European Union 15 Years after Accession: Estonia, Latvia, Lithuania and Poland
    (2022)
    Iveta Graudina
    ;
    Iluta Arbidane
    ;
    Agate Viluma
    Within the EU program “Europe for Citizens”, the project "The 15th Anniversary of the EU Enlargement", implemented by four NGO from Estonia, Latvia, Lithuania, and Poland, the research on the attitudes of the population to the European Union and the issues related to the EU development. Among the concepts used in the research, the constructs of place attachment and social identity were chosen. Quantitative and qualitative data was collected, including 88 in-depth interviews and 467 questionnaires. Conclusions were drawn showing that national and place identity is stronger than construct of “European identity” among the respondents.
  • Publication
    CHANGES AND PROBLEMS OF WORK ORGANIZATION IN COVID-19 CONDITIONS IN LATVIA
    (2021)
    Iluta Arbidane
    ;
    Iveta Mietule
    ;
    Iveta Graudina
    ;
    Sanita Sinavska
    ;
    Anda Zvaigzne
    The spread of the Covid-19 pandemic introduced restrictions that challenged companies to restructure to stay in business. The company managers ability to initiate changes in work organization is crucial to ensure the companies existence and successful business continuity. The research aims to study the development trends and problems of work organization in Covid-19 conditions. To achieve the aim the legal framework for work organization was studied, changes in work organization in the Baltic States and the EU were analysed, and two surveys on changes in work organization one for employers and the other for employees were conducted. Monographic and document analysis methods, statistical data processing methods, sociological survey method were used in the research. The study analyses the development trends of work organization in the conditions of Covid-19, defines the problem questions, and makes proposals regarding solution of work organization problems.
  • Publication
  • Publication
    Comparative Evaluation of Four Methods for Exploratory Data Analysis
    (2021)
    Oleg Uzhga-Rebrov
    ;
    Grabusts, Pēteris 
    Research activities in many areas are associated with the use of various types of data. This data may contain important information, but this information is hidden in the data. In order to extract relevant information, this data must be subjected to appropriate processing and analysis. Data analysis allows to clarify the data structure and, if necessary, transform the data into a form that allows to extract the required information. In recent years powerful data analysis techniques have been developed. Typically, these methods are computationally complex and require the use of suitable software to implement. This paper summarizes and analyses four widely used methods of exploratory data analysis: principal component analysis, singular value decomposition, factor analysis, and linear discriminant analysis.
    Scopus© Citations 1
  • Publication
    CONCEPTUAL MODEL FOR THE DEVELOPMENT OF TEACHERS’ DIGITAL COMPETENCE
    (2021)
    Janis Dzerviniks
    ;
    Svetlana Usca
    ;
    Velta Lubkina
    ;
    Janis Poplavskis
    ;
    Aija Vindece
    The COVID-19 pandemic contributed to the fact that distance learning became a reality and the traditional school began to transform into an online and virtual school. The introduction of distance learning further raised the issue of the need for teachers to continuously improve their digital competences. In Latvia, digitization processes in general education are under development. A modern vision is a pupil, who is able to identify reliable information, cite sources, protect his/her intellectual property, express attitudes and ethical values, create his/her digital resources, and reflect on his/her learning and development. Digital transformation in education is an important process of change, which is based on the change of content, organizational forms, methods, teaching aids for work in the digital educational environment. Both the teacher's knowledge and skills and a positive attitude are important in the implementation of changes. Continuous professional development is important for teachers' digital growth, which includes the acquisition of knowledge and skills in the use of digital technologies in the initial study process, practice, starting professional activities, improving professionalism in the workplace in cooperation with colleagues, participation in competitiveness and personal development activities, as well as acquiring professional competence development programs. The paper analyzes the content of teachers' digital competence and describes a conceptual model for the development of teachers' digital competence in the cultural environment of Latvia.
  • Publication
    CREATIVE SELF-EFFICACY AND UNIVERSITY STUDENTS’ PROSPECTIVE EMPLOYABILITY: CASE OF LATVIA
    (2019)
    Svetlana Usca
    ;
    Inta Rimsane
    ;
    Iveta Mietule
    The labour market of the 21 st century demands not only occupation-specific skills but also employability skills, attributes, experiences, and dispositions. Theoretical knowledge of the prospective employees is not a quality indicator any more. Contemporary employers expect that university graduates have not only teamwork, problem-solving, communication, decision-making skills, but also personal initiatives, self-confidence, emotional intelligence, willingness to learn, creativity, ability to create innovative ideas and many more. Latvia is currently facing a shortage of creative workforce which is able to present and manage the innovative ideas. The goal of this study is to examine the university students’ awareness about the importance of the creativity and innovations in the prospective employability. The study covered 238 respondents from 4 higher education institutions that in Latvia offer the BA study programmes in pedagogy, economics, design, public relations and psychology. It turned out that 49 % of the students deny their ability to create new ideas which can prevent them from developing a successful career in future. The research concluded that in organising the study process in higher education institutions, attention should be paid not only to the acquisition of professional knowledge and skills, but also to the development of the personal aspects, for example, creative self-efficiency of future specialists. Global labour market requires a paradigm shift in the content of the study programmes and teaching methods of higher education institutions of Latvia. Recommendations for future research are also proposed.
  • Publication
    Decision Making Based on Possibility Theory
    (2022)
    Oleg Uzhga-Rebrov
    ;
    Grabusts, Pēteris 
    In decision-making problems under risk, one of the main tasks is to evaluate the probabilities of the occurrence of such random events that affect the outcomes of alternative decisions. In some specific situations, due to the lack of initial information, it is difficult or even impossible to perform such evaluation. In this article we present an alternative approach to choosing decisions under uncertainty. This approach is based on the possibility theory, which is at the intersection of various developed theories of uncertainty: the theory of fuzzy sets, the theory of evidence and the theory of probabilities. Evaluating the possibilities of relevant events is a simpler task than evaluating the probabilities of these events. The article presents the conceptual foundations of the possibility theory. The use of this theory for decision making is demonstrated with a simple illustrative example.
  • Publication
    Determination constants of 4-element reological model with rebound resilience method
    (2017)
    Martinovs, Andris 
    ;
    Svetlana Polukoshko
    ;
    Elvijs Apeinans
    ;
    Zaicevs, Edgars 
    In this paper an express-method and equipment for experimental determination of the 4-element rheological model constants (2 elastic modulus, 2 viscosity coefficients) for elastomers are developed. The method is based on rebound of falling hammer against an elastomer material. A mathematical model for describing this collision is elaborated and an algorithm for determination of the constants of the model was developed and realized in Matlab software. Time necessary for determination of the constants is until 5 minutes. It gives an opportunity to significantly accelerate the design and production process of elastomer-metal vibration isolator prototypes with defined parameters of stiffness and damping. The method allows to trace displacement, velocity and acceleration of the metal parts of the shock absorber throughout the collision; this may be realized with Matlab or an analogical program of numerical integration. For forecasting of the mechanical properties of the shock absorber during a long period (considering the aging of elastomer) it is necessary to know the rheological model parameter dependence on time, temperature, energy input and other factors; the proposed method allows to significantly accelerate these experimental studies.
    Scopus© Citations 2
  • Publication
    Development of Teachers' Digital Competence: Problems and Solutions in Latvia
    (2021)
    Svetlana Usca
    ;
    Janis Dzerviniks
    ;
    Velta Lubkina
    ;
    Aija Vindece
    ;
    Janis Poplavskis
    The data obtained from the Latvian National research programme “Life with COVID-19: Evaluation of the coming coronavirus crisis in Latvia and recommendations for social resilience in the future (CoLife)” show that the successful implementation of remote learning requires the improvement of teachers' digital competence. The professional development courses organized before the COVID-19 pandemic (their content, form) do not meet the needs of the real situation. It is necessary to look for new forms so that the content of professional development courses meets the needs of current general education teachers, including not only general skills characterizing digital competence, but also specific ones related to the level of education (age of learners) and field of study. The aim of the research: to identify the needs of general education teachers for the development of digital competence and to prepare proposals for the implementers of professional competence development courses. Research methods: online survey of 559 teachers, survey of 6 experts, quantitative data processing in SPSS program, content analysis of qualitative data. The research concluded that teachers' professional competence development courses should be practice-oriented, as close as possible to the technical capabilities of an educational institution, as well as considering the current needs of teachers, the field of subjects taught and the level of education at which they work.