Database.use.hdl: https://cris.mruni.eu/cris/handle/007/20876
Now showing 1 - 10 of 27
  • research article
    Engineering analysis with boundary elements. Oxford : Pergamon-Elsevier, 2013, Vol. 37, iss. 4., p. 788-804
    Various real-world processes usually can be described by mathematical models consisted of partial differential equations (PDEs) with nonlocal boundary conditions. Therefore, interest in developing computational methods for the solution of such nonclassical differential problems has been growing fast. We use a meshless method based on radial basis functions (RBF) collocation technique for the solution of two-dimensional Poisson equation with nonlocal boundary conditions. The main attention is paid to the influence of nonlocal conditions on the optimal choice of the RBF shape parameters as well as their influence on the conditioning and accuracy of the method. The results of numerical study are presented and discussed.
    WOS© IF 1.437WOS© AIF 1.403Scopus© SNIP 1.633
  • research article
    Kosareva, Natalja
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    Technological and economic development of economy. Vilnius : Technika, 2013, vol. 19, no. 1., p. 162-187
    The paper defines the notions of point, interval and triangular intuitionistic fuzzy numbers expressing the degree of membership and non-membership in the fuzzy set. The generalized fuzzy weighted average function is introduced according to operation rules on intuitionistic fuzzy numbers. In special cases, the generalized weighted average coincides with an arithmetic average or a geometric average. The generalized fuzzy weighted average function could be applied for solving problems in multiple criteria decision making. Research on the stability of the generalized weighted averaging operator of ranking alternatives was performed applying the Monte Carlo method. The aim of the conducted research is to establish the types of intuitionistic fuzzy numbers and the exponent values of the generalized weighted averaging operator having the least error probabilities considering alternatives ranking. Computations were performed involving 3, 4 and 5 experts. In the case of 5 experts, initial decision matrices having high, middle and low separability alternatives were examined. Decision matrices created by the experts were modelled generating random intuitionistic fuzzy numbers according to uniform and normal distribution. The example of applying such methodology was shown to solve a real problem of ranking possible redevelopment alternatives for derelict rural buildings.
      1WOS© IF 2.818WOS© AIF 1.244
  • research article
    Vaiškūnaitė, Rasa
    ;
    ;
    Špakauskas, Valdas
    Transport : journal of Vilnius Gediminas Technical University and Lithuanian Academy of Sciences. Vilnius : Technika, 2012, vol. 27, no. 2., p. 187-195
    Roads affect wildlife in different ways. Road construction increases fragmentation of habitats, influences landscape pattern and alters the physical environment. Roads act as barriers to animal movements, increase their mortality rates and cause other negative impacts on biodiversity. The current paper overviews the assessment of road impacts in Lithuania, reviews approaches applied to evaluation of road development impacts as well as analyses application of Lithuanian legal documents in the field. In Lithuania, assessment of possible effects inflicted by envisaged road construction is determined by the Law on Environmental Impact Assessment of Planned Economic Activities and orders of the Ministry of Environment. Although the legislation covers some aspects of biodiversity, little attention is given to the assessment of the impact on biodiversity; meanwhile the impact assessment of proposed economic activities on Natura 2000 sites is clarified more extensively. Lithuanian methodological guidelines on determination of environmental impact assessment procedures and principles for the road network do not comply with international requirements concerning the biodiversity impact assessment of roads. The practiced biodiversity impact assessment used for road development projects in Lithuania complies with minimum requirements used in developed countries. To fulfil international requirements on biodiversity conservation, it is necessary to amend the Lithuanian legislation on environmental impact assessment and issue guidelines on biodiversity protection in road development projects, The article proposes models for calculation of road pollution dispersion for evaluation of air quality next to the already existing and newly projected roads.
    WOS© IF 1.081WOS© AIF 1.197Scopus© SNIP 0.713
  • research article
    Computers and mathematics with applications. Kidlington : Pergamon, 2012, vol, 64, no 11., p. 3485-3499
    Nonlocal conditions arise in mathematical models of various physical, chemical or biological processes. Therefore, interest in developing computational techniques for the numerical solution of partial differential equations (PDEs) with various types of nonlocal conditions has been growing fast. We construct and analyse a weighted splitting finitedifference scheme for a two-dimensional parabolic equation with nonlocal integral conditions. The main attention is paid to the stability of the method. We apply the stability analysis technique which is based on the investigation of the spectral structure of the transition matrix of a finite-difference scheme. We demonstrate that depending on the parameters of the finite-difference scheme and nonlocal conditions the proposed method can be stable or unstable. The results of numerical experiments with several test problems are also presented and they validate theoretical results.
    WOS© IF 2.069WOS© AIF 1.446Scopus© SNIP 1.654
  • research article
    Brauers, Willem K.M.
    ;
    ;
    Baležentis, Tomas
    Technological and economic development of economy. Vilnius : Technika, 2012, vol. 18, iss. 4., p. 567-587
    It is the intention of the European Union to create a growing and sustainable European economy by 2020, a much more moderate target than the 2010 target of becoming the most competitive and dynamic knowledge-based economy in the world. This intention has to be supported by an adequate Optimization and Decision Support System. Therefore, MULTIMOORA is proposed. MULTIMOORA is a quantitative method, which compares multiple and optimum objectives, expressed in different units, as much as possible on a nonsubjective basis. In opposition to similar methods MULTIMOORA does not need normalization, being based on dimensionless measures. Importance of an objective can eventually be given by the stakeholders concerned. MULTIMOORA is composed of three approaches: Ratio System, Reference Point and Multiplicative Form Methods, all of the same importance and each controlling each other. Twenty two objectives, 10 originating from statistics and 12 from statistics and forecasts, important for the future, characterize the 27 EU-Countries economies as a preparation for 2020. Which of these countries are the best prepared for 2020? A Dominance Theory, summarizing the three obtained ordinal numbers per country, ranks the 27 countries for that purpose.
    WOS© IF 3.224WOS© AIF 1.193
  • research article;
    Jakovlev, Sergej
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    Adomaitis, Danielius
    ;
    Transport. Vilnius : Technika, 2012, vol. 27, no. 1., p. 40-48
    Over the last few years, a large number of researches have emerged and approached the use of mobile expert systems and other information management technologies in the area of intermodal container transportation and decision support. However, practitioner literature poorly analyzes the process of monitoring cargo transportation conditions, cargo information security and other important issues. The paper presents an emerging field of intermodal container transportation where the primary objective of the proposed mobile control system is to monitor cargo conditions during transportation in a real time manner and work as a decision support system. Also, the article evaluates potential risks involved in cargo transportation and therefore provides mobile cargo security assurance service. Computational results suggest using an optimum number of RFID and sensor readings to effectively manage the newly proposed elements of operation strategy in a conceptual strategy framework. The overall results indicate that the integration of risk management practice into transportation processes via a mobile control system increases intermodal container transportation mobility, safety and overall effectiveness.
    WOS© IF 1.081WOS© AIF 1.197Scopus© SNIP 0.713
  • research article;
    Baležentis, Tomas
    ;
    Misiūnas, Petras Algimantas
    Technological and economic development of economy. Vilnius : Technika, 2012, vol. 18, iss. 1., p. 34-53
    The aim of this study was to offer a novel procedure for integrated assessment and comparison of Lithuanian economic sectors on the basis of financial ratios and fuzzy MCDM methods. The complex of interrelated issues regarding integrated assessment of economic sectors is discussed in the paper. The object of research is financial indicators of different Lithuanian economic sectors. The proposed procedure for multi-criteria comparison of economic sectors encompasses: 1) the indicator system, 2) application of fuzzy MCDM methods, and 3) inter-sectoral comparison based on ranks provided by fuzzy MCDM methods. The research covers period of 2007–2010, starting at the very beginning of the economic recession and, hopefully, ending with the upcoming recovery. The application of the three MCDM methods was successful. The results suggested the best performing sector being that of forestry and logging. Furthermore, enterprises operating in trade sector, hospitality sector, mining and quarrying sector, information sector, or manufacturing sector can be considered as working more efficiently than an average Lithuanian enterprise. At the other end of spectrum, construction, real estate, and transportation sectors were those severely damaged by the economic crisis: they were ranked below the average alternative. Meanwhile, relatively low positions of utilities sectors may be caused by their specifics. Finally, the transport sector can be considered as the typical victim of economic downturn.
    WOS© IF 3.224WOS© AIF 1.193
  • Publication
    Iracionalumo apraiškos xx a. užsienio ir Lietuvos architektūroje
    [Irrationality in global and Lithuanian architecture of the 20th century]
    research article
    Mačiulis, Algimantas
    Urbanistika ir architektūra = Town planning and architecture. Vilnius : Technika, 2010, Nr. 34(3)., p. 151-160
    Straipsnyje analizuojamas iracionalumas kaip šiuolaikinės architektūros meninės išraiškos forma, aptariama iracionalumo sąvoka architektūros mene. Taip pat charakterizuojamos sociokultūrinės prielaidos, filosofinės, meno srovės, dariusios įtaką iracionalumo požymiams architektūroje. Nagrinėjami pasauliniai ir Lietuvos iracionaliosios architektūros analogai, apžvelgiamos iracionalumo apraiškos stilistinėje architektūros raidoje.
  • Publication
    Multi-agent-based human computer interaction of e-health care system for people with movement disabilities
    [Моделирование многоагентной oбoлoчки человеческо-компьютерного общения системы э-здоровья для людей с недугом по подвижности]
    research article
    Bielskis, Antanas-Andrius
    ;
    Denisov, Vitalij
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    Drungilas, Darius
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    ;
    Electronics and electrical engineering = Электроника и электротехника = Elektronika ir elektrotechnika. Kaunas : Technologija, 2010, no. 7 (103)., p. 77-82
    This paper presents further development of intelligent e-health care system for people with movement disabilities. The research results present the development of multi-agent-based human computer interaction model and its integration into the system of fuzzy neural control of speed of two wheelchair type robots to providing movement support for disabled individuals. An approach of filtering of skin conductance (SC) and electrocardiogram (ECG) signals using Nadaraya-Watson kernel regression smoothing in R tool for emotion recognition of disabled individuals is described and implemented in the system. The unsupervised clustering by self organizing maps (SOM) of data sample of physiological parameters extracted from SC and ECG signals noninvasively measured from disabled was proposed. It was implemented to reduce teacher noise as well as to increase of speed and accuracy of learning process of multi-layer preceptron (MLP), which was applied in the multi-agent-based human computer interaction model for online prediction of e-health care state of disabled individuals.
      10WOS© IF 0.659WOS© AIF 1.462
  • Publication
    Ensuring efficiency of electronic devices
    [Elektroninių įtaisų efektyvumo užtikrinimas]
    research article
    Elektronika ir elektrotechnika = Electronics and electrical engineering = Электроника и электротехника. Kaunas : Technologija, 2010, Nr. 1(97)., p. 15-18
    Electronic devices which that are inspected by using built-in test equipment are considered. The method of ensuring requirements of efficiency index of devices is analyzed. It is shown that the index of efficiency depends on simple index of reliability: mean time between failures and mean time of restoration. The method of ensuring requirements of time between failures provides distribution of serviceability requirements between parts of the device. The opportunities of exception of some failures from the general flow, multifunctional nature of device are taken into account. The method of ensuring requirements of mean time of restoration provides an estimation of separate components of the given index. The expediency of development of complete sets of stocks of components is considered. The question of necessity of specifying stocks of components according to the results of exploitation of devices is analyzed.
    WOS© IF 0.659WOS© AIF 1.462