Vilnius Gediminas Technical University
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SOCIALINIS VERSLAS: KÛRIMO IR PLËTROS POREIKIAI
No full textThis theoretical article dealt with social business and
its creation and development processes. Current
problems of the creation and development of social
business are discussesd in details.
The essence of social business is described in detail,
main fundamental notions are defined. The role of
the social business and its creation and development
in the life of contemporary society is revealed.
Importance and significance of the social business and
its creation and development processes in the context
of contemporary aspirations of the harmony and
sustainability are displayed. The principles and
regularities of the creation and development of social
business are described in details. The impact of the processes of globalization, knowledge-based society and
knowledge economy creation, of the processes of
European integration and the European Union’s
development on the social business and its creation
and development is revealed. Priorities of the scientific
research on the social business and its creation and
development are described
High-low Strategy of Portfolio Composition using Evolino RNN Ensembles
No full textStrategy of investment is important tool enabling better investor’s decisions in uncertain finance market. Rules of portfolio selection help investors balance accepting some risk for the expectation of higher returns. The aim of the research is to propose strategy of constructing investment portfolios based on the composition of distributions obtained by using high–low data. The ensemble of 176 Evolino recurrent neural networks (RNN) trained in parallel investigated as an artificial intelligence solution, which applied in forecasting of financial markets. Predictions made by this tool twice a day with different historical data give two distributions of expected values, which reflect future dynamic exchange rates. Constructing the portfolio, according to the shape, parameters of distribution and the current value of the exchange rate allows the optimization of trading in daily exchange-rate fluctuations. Comparison of a high-low portfolio with a close-to-close portfolio shows the efficiency of the new forecasting tool and new proposed trading strategy
Gaisrų gesinimo ir gelbėjimo automobilių kėbulo elementų patikimumo tyrimas
No full textŠiame straipsnyje pateiktas gaisrų gesinimo ir gelbėjimo automobilių kėbulo elementų patikimumo tyrimas. Darbas atliktas išanalizavus mokslinę literatūrą, kurioje nagrinėjami gaisrinių automobilių kėbulo elementų konstrukciniai ypatumai, įvertinant pagrindinių kėbulo elementų patikimumą. Išnagrinėtos jėgos, veikiančios gaisrinių automobilių kėbulo elementus, nustatytos silpnosios konstrukcijos vietos, vertinant pagrindinius konstrukcinius elementus (porėmį, kėbulą). Remiantis sudarytais skaitiniais modeliais (Solidworks programinio paketo aplinkoje), atliktas gaisrinio automobilio kėbulo konstrukcijos pagrindinių elementų stiprumo charakteristikų įvertinimas, modeliuojant apkrovas pavojinguose pjūviuose. Darbo pabaigoje pateikiama rezultatų analizė bei pasiūlymai
Tackling projects on sustainability: a Lithuanian case study
No full textCompanies are increasingly coming under strong global pressure to incorporate sustainability considerations into their project decision-making process. This is where project managers play a vital role. However, how project managers approach sustainability in their daily work still has to be explored. Therefore, this article seeks to determine whether and to what extent project managers take into account sustainability in project management decision making. Research was carried out in Lithuania, selecting two industries: construction and automotive. The case study revealed that project managers in Lithuania still do not give much regard to sustainability when making their decisions. Only a limited number of sustainability criteria are taken into account by project managers in their decisions. Research also showed that a project manager gives more consideration to sustainability in project management decision making than a project team member
Spoof plasmons affected by the corrugated structures
No full textAs reported by Ritchie, the fundamental optical excitations that are confined to a metal/dielectric interface are referred as the surface plasmon polaritons. In the present study, we report on a theoretical investigation of the dispersion relation of surface plasmon polaritons on the periodically corrugated surfaces. Tunability of these structures can be enhanced further changing the employed material
Vartotojų sukuriamų srautų balansavimas heterogeninio korinio ryšio tinkluose
Get PDFDisertacijoje nagrinėjami heterogeninių korinio ryšio tinklų talpos ir paslaugų kokybės užtikrinimo klausimai, taikant vartotojų srauto balansavimą. Pagrindiniai tyrimo objektai yra vartotojų sukuriamo balso ir duomenų srauto balansavimas tinkle. Srauto balansavimas yra svarbi sritis šių dienų telekomunikacijose, kai perduodamų duomenų srautai auga milžiniškais tempais. Įvairiapusiška ir lanksti vartotojų srauto balansavimo metodika leidžia efektyviai valdyti srautą tinkle, sumažinant tinklo apkrovą ir investicijas. Pagrindinis disertacijos tikslas – ištirti išplėstines vartotojų srautų balansavimo galimybes korinio ryšio sistemose. Darbe siekiama įvertinti srauto balansavimo įtaką tinklo vartotojams bei tinklui.
Darbe sprendžiami du pirmieji uždaviniai apima: balso paslaugų vartotojų srauto analizę, pagal vartotojų buvimo vietą, bei balso srauto balansa-vimą, taikant tarpsisteminius srauto balansavimo metodus. Kiti du uždaviniai siejami su vartotojų siunčiamo duomenų srauto augimu, kuris sukelia tinklo ląstelių persipildymą. Duomenų srauto valdymui taikomi paslaugų klasifikavimo pagal QoS ir tarpsluoksnio balansavimo metodai, kurie remiasi mažomis ląstelėmis.
Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašai, priedai, reziumė anglų kalba.
Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas bei uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Pabaigoje pristatomos disertacijos tema autoriaus paskelbtos publikacijos bei disertacijos struktūra. Pirmasis skyrius yra skirtas literatūros analizei. Jame aptariama srautų balansavimo samprata bei poreikis. Skyriuje pateikiama išsami srauto balansavimo metodų apžvalga, analizuojami konkretūs balso ir duomenų balansavimo būdai. Antrame skyriuje nagrinėjamas balso srauto pasiskirstymas realus korinio ryšio tinkle pagal surinktus metaduomenis. Skyriuje pateiktos srauto charakteristikos. Iš tinklo veiklos rodiklių nustatyta balso balansavimo įtaka tinklui ir vartotojams. Trečiasis skyrius atskleidžia duomenų srauto QoS prioriteto reikšmę paslaugų kokybei vienodomis ir skirtingomis ryšio kanalo sąlygomis. Tarpsluoksnio srauto balansavimo atveju pateiktas femto zoną reprezentuojantis modelis ir įvertinta ryšio paslaugų vartotojų patiriama paslaugų kokybė femto zonose. Tyrimai atliekami realiomis radijo aplinkos sąlygomis.
Disertacijos tema paskelbti 7 moksliniai straipsniai recenzuojamuose mokslo leidiniuose: 4 straipsniai mokslo žurnaluose referuojamuose kitose tarptautinėse duomenų bazėse ir 3 straipsniai konferencijų medžiagose. Di-sertacijos tema perskaityti 7 pranešimai Lietuvos ir užsienio šalių konferencijose
Strypinės armatūros išdėstymo įtaka betoninių elementų deformacijoms ir pleišėjimui
Get PDFThe aim of this work is to investigate the arrangement effect of bar reinforcement to deformations and cracking behaviour of concrete elements subjected to short-term loading. The study experimentally verifies the effective concrete area concept and analyses peculiarities of cracking process of reinforced concrete (RC) members with the emphasis on arrangement of the bar reinforcement. The test results of 9 beams and 119 ties with different reinforcement and loading layouts are reported.
Results of the beam tests do not reveal a clear correlation between the crack widths and the crack spacing when the reinforcement layout changes, while the number of the reinforcement layers correlates with the flexural stiffness.
An iterative procedure has been proposed for localizing the end effect in the ties. This procedure allows identifying the representative geometry for assessing the cracking parameters of RC ties. It was observed that scatter of the experimental outputs increases with the concrete cover.
Specific equipment has been developed for tests of the ties with multi-ple reinforcement bar. The test results (maximum and average crack spacings) are practically independent of the reinforcement parameters, while the Eurocode 2 and the Model Code 2010 predictions of the maximum crack spacing are dependent on the ratio of the bar diameter to the reinforcement ratio. These results enable formulating a hypothesis that the crack parameters (spacing and width) are mainly dependent on the geometry of the con-crete prism and, particularly, the cover depth.
Deformation behaviour of the ties with multiple reinforcement bars was also modelled with nonlinear finite element software ATENA. The results of numerical simulations and physical tests indicate that the strain gra-dient in the concrete varies not only along the bar, but also within the cover. The outputs support a conclusion that the “effective area” concept has a limited application related with the loading conditions, stress-strain state, cover, and configuration of the unreinforced area.
The thesis is composed of three chapters: literature survey, experimental
programs, and discussion of the results. The literature survey is focused on the effects responsible for deformation and cracking performance of rein-forced concrete members. The experimental study deals with deformations and cracking of
flexural and tensile elements with different arrangement of the reinforcement in the tension zone. The last chapter discusses predominant characteristics of serviceability performance of flexural and tensile reinforced concrete members. The author have published 14 articles on the topic of the dissertation (five of them in the journals with an Impact Factor and three in the conference proceedings reffered by the Clarivate Analytics Web of Science)
Messages of architectural objects
No full textThe article aims at revealing the role of architecture in programming
ethically significant content in the observer’s consciousness.
The concepts of intext and metatext are very helpful in this situation. The
knowledge about semantization levels, different types of metalanguage that
work in the programming of mind, about the role of metalogic information
that is adjusting attitudes is crucial. Original criterion system and certain
instruments of such evaluation analysis were created using theoretical methods:
abstraction, analogy, generalization, reasoning, synthesis. Moreover,
methods of phenomenology and semantic analysis were applied
Evaluation of park and ride facilities at communication corridors in a middle-sized city
No full textRapid rise in car ownership in cities of Lithuania, particularly in capital Vilnius, has multiplied continuous traffic jams in the streets of the city and thus increased necessity of development of effective urban solutions designated for optimising transportation in urban areas and reducing negative transport effects. In order to lay down foundation for building a successful remedy Vilnius city municipality administration is planning to submit an application to receiving financial support for the implementation of the Park-and-Ride (hereinafter P&R) scheme for Vilnius within the framework of the European Union (hereinafter EU) Structural Assistance for the period 2014-2020. Multiple criteria decision-making methodology for selecting beneficial sites of P&R lots and for outlining desirable directions of development of the city of Vilnius with incorporated P&R facilities was employed in the paper. The methodology uses a set of descriptive criteria for planning the P&R scheme; expert evaluation was used for estimation of weights of significance of the chosen criteria
A new fuzzy hybrid multi-criteria decision-making approach to solve personnel assessment problems. Case study: director selection for estates and economy office
No full textPersonal selection is known as one of the most important parts of human resource management. Economic performance of organisations depends on effective and proper management. Hybrid fuzy multi-criteria decision-making approachpresented in the paper take into consideration the quantitative or objective criteria but also the ones appear to be qualitative or subjective. Such methods are mainly designed to evaluate and compare alternatives, are independent of the assessment models that are used (since they are mainly based on expert judgement), and therefore represent a practical tool to assist decision-making in complex projects