117 research outputs found
From Pentecost to 'inner healing': religious change and Pentecostal developments in the post-socialist Lithuanian Catholic milieu
No full textSaulius Matulevicius, Vytautas Magnus University.
Saulius Matulevicius is a PhD student at the University of Vytautas Magnus, Sociology department. He studies Pentecostal Christianity and its vernacular developments. His field of interest in anthropology covers religion, secularisation, secularist politics and the post-secular, death and mourning, also media and organisational anthropology. He also is a lecturer at the ISM University of Management and Economics and Vytautas Magnus University.In this article the author describes the religious change that took place in the Catholic milieu of post-Soviet Lithuania. Following the arrival of global Pentecostal trends to the country a Catholic form of Pentecostalism, known as Catholic Charismatic Renewal (CCR) also arrived. The author describes what changes the CCR brought and how the Pentecostal developments paved the way for this other movement to emerge. Dynamic developments of the CCR unexpectedly took a turn towards the discourse and practice of healing, which triggered the emergence of another movement, known as the Inner Healing Movement (IHM). Being inseparable from its Pentecostal roots the movement, nevertheless, has become a vernacular, specifically Catholic, practice which no longer seeks for the signs of Pentecostal authenticity but redefines the Pentecostal message, directing it towards healing discourses and practices
Theoretical study of direct and indirect single ionisation by electron impact.
No full textThe dissertation analyses the processes of single ionisation with electron impact using the distorted wave approximation. The work focuses on W5+, W25+, W26+, Fe3+ and Se3+ ions. The atomic data of these ions are important and have practical application perspectives for understanding and controlling astrophysical processes and thermonuclear plasma dynamics. The direct and indirect ionisation processes of ions are analysed, and the cross sections of the ionisation effect are determined. The correlation effects of Fe3+ and W5+ ions were also investigated and the experimental data of these ions and Se3+ ion were explained for the first time. The introduction discusses the importance of plasma studies and the need to investigate ionisation in iron, selenium, and tungsten. The work aims to investigate the processes of single ionisation by electron impact using the distorted wave method and to propose more accurate methods. The main theory is discussed in the theoretical chapter: electron impact ionization, wave functions, radiation and Auger transitions, resonant excitation-double autoionisation process, distorted wave approximation, cross section scaling coefficient, correlation effects, modelling of metastable states. The dissertation concludes with the main conclusions that are related to the defended statements. The dissertation is prepared in English, its volume is 103 pages. The dissertation consists of content, the list of author's publications and conference papers, the list of abbreviations used in the dissertation, introduction, theory overview, the results section, conclusions, and the list of used literature with 98 sources. The dissertation contains 33 illustrations, 5 tables and 1 appendix
Tiesioginės ir netiesioginės viengubos jonizacijos elektronų smūgiais tyrimas.
No full textThe dissertation analyses the processes of single ionisation with electron impact using the distorted wave approximation. The work focuses on W5+, W25+, W26+, Fe3+ and Se3+ ions. The atomic data of these ions are important and have practical application perspectives for understanding and controlling astrophysical processes and thermonuclear plasma dynamics. The direct and indirect ionisation processes of ions are analysed, and the cross sections of the ionisation effect are determined. The correlation effects of Fe3+ and W5+ ions were also investigated and the experimental data of these ions and Se3+ ion were explained for the first time. The introduction discusses the importance of plasma studies and the need to investigate ionisation in iron, selenium, and tungsten. The work aims to investigate the processes of single ionisation by electron impact using the distorted wave method and to propose more accurate methods. The main theory is discussed in the theoretical chapter: electron impact ionization, wave functions, radiation and Auger transitions, resonant excitation-double autoionisation process, distorted wave approximation, cross section scaling coefficient, correlation effects, modelling of metastable states. The dissertation concludes with the main conclusions that are related to the defended statements. The dissertation is prepared in English, its volume is 103 pages. The dissertation consists of content, the list of author's publications and conference papers, the list of abbreviations used in the dissertation, introduction, theory overview, the results section, conclusions, and the list of used literature with 98 sources. The dissertation contains 33 illustrations, 5 tables and 1 appendix
ŠILUMOS SIURBLIO DARBO REŽIMŲ ANALIZĖ
No full textEfektyviam šildymo sistemos su šilumos siurbliais darbui didelę įtaka turi tikslus šilumos siurblio sistemos parinkimas. Projektavimo metu svarbu atsižvelgti į sistemos įrengimo ir eksploatavimo išlaidas. Skaičiuojant eksploatacines išlaidas reikia žinoti, kokiomis sąlygomis ir kokiu režimu dirbs šilumos siurblys ir koks galėtų būti jo sezoninis naudingumo koeficientas (angl. SPF – seasonal performance factor). Darbe nagrinėjamos realiai veikiančio šilumos siurblio energijos sąnaudos. Nustatyta, kad faktinis šilumos siurblio naudingumo koeficientas SPF atitinka standartų reikalavimus. Remiantis faktiniais duomenimis atliekama šilumos siurblio darbo režimų analizė. Nagrinėjami šie režimai: monovalentis, monoenergis, dvivalentis–alternatyvus ir dvivalentis–lygiagretus. Kaip papildomas (alternatyvus) šilumos šaltinis pasirenkamas gamtinių dujų katilas. Nustatyta, kad didžiausias elektros poreikis pastato šildymui yra monoenergio režimo atveju, mažiausias – dvivalenčio–alternatyvaus (0 °C). Didžiausios gamtinių dujų sąnaudos yra dvivalenčio–alternatyvaus (0 °C) režimo atveju, mažiausios – dvivalenčio–lygiagretaus (-5 °C). Didžiausia šilumos kaina yra dvivalenčio–alternatyvaus (0 °C) režimo atveju, mažiausia – monovalenčio režimo atveju. Didžiausios pradinės investicijos reikalingos monovalenčio režimo atveju, mažiausios – monoenergio.</jats:p
Research of characteristics of a phase change material based thermal energy storage unit
No full textDisertacijoje taikant analitinį modelį, skaitinį modeliavimą ir eksperimentinius tyrimus tiriamas fazinio virsmo medžiagos pagrindu veikiantis šilumos kaupimo
įrenginys.
Darbe sprendžiami keli pagrindiniai uždaviniai, susiję su fazinio virsmo medžiagų termofizikinių savybių, šilumokaičio geometrijos ir šilumnešio parametrų įtaka fazinio virsmo medžiagos (FVM) pagrindu veikiančio šilumos kaupimo renginio veikimo charakteristikoms.
Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašai ir du priedai.
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. Įvado pabaigoje pristatomos disertacijos tema autoriaus paskelbtos publikacijos ir pranešimai konferencijose bei disertacijos struktūra.
Pirmasis skyrius skirtas literatūros analizei. Skyriaus pabaigoje formuluojamos išvados ir tikslinami disertacijos uždaviniai.
Antrajame skyriuje pateikta FVM pagrindu veikiančio šilumos kaupimo
įrenginio tyrimų metodika, kurios pagrindu atliekamas kompleksinis tyrimas,
apimantis skaitinį modeliavimą, analitinių išraiškų taikymą ir eksperimentus.
Trečiajame skyriuje pateikti FVM pagrindu veikiančio šilumos kaupimo
įrenginio tyrimų rezultatai. Analizuojami skaitinio modeliavimo rezultatai, nagrinėjant temperatūros pasiskirstymą ir fazės virsmo trukmę pasirinktuose FVM šilumos kaupimo įrenginio taškuose ir plokštumoje. Atliekamas šilumos atidavimo koeficiento nustatymas taikant analitines išraiškas, gauti rezultatai lyginami su eksperimentiniais. Aprašomi ir analizuojami eksperimentinių tyrimų, apimančių FVM tankio kitimo, šilumokaičio geometrijos, šilumnešio masinio debito ir temperatūros įtaką įrenginio veikimo charakteristikoms, rezultatai.Daktaro disertacij
Editing experimental prose: the case of saulius tomas kondrotas.
No full textThe agent of an editor due to the specifics of this role in the literary field is often regarded as ‘invisible’ or ‘secret’. The aim of this bachelor’s thesis is to analyse editorial input in the process of creating prose texts, therefore a triangle of relationships between author, editor and text is examined. The research is carried through an edited typescript of the novel ‘Žalčio žvilgsnis’, written by Saulius Tomas Kondrotas. The material indicates novelty of the author, which was not recognized by the editor because of editor’s or publisher’s stylistic automatism. Correspondingly, the author of this thesis hypothesizes that these are signs of cultural or philosophical friction, hence they are used to examine the presumption. Theory and methods that had been chosen as a base for the research are the principles of textual criticism. Previous studies and reviews of the novel ‘Žalčio žvilgsnis’ are applicable, too
Fazinio virsmo medžiagos charakteristikų šilumos kaupiklyje skaitinis modeliavimas / Simulation of the phase change materials’ characteristics in a thermal energy storage
No full textIn order to use efficiently residual, waste or renewable energy, the application of phase change materials (PCM) grows in building energy systems. At the same time, this poses new technological challenges in choosing specific materials, system design solutions, because it requires a specific knowledge of the heat transfer process during the phase change. The aim of the work is to investigate the heat transfer in a PCM based thermal energy storage unit using the COMSOL Multiphysics software. In the analysis, the properties of the material were evaluated during the phase change. This allowed to determine that the thermal conductivity of the material is of great importance for the intensification of heat transfer. In addition, the analysis of several points in the analyzed object revealed that the phase change does not occur in the surface layer of the PCM during the period under consideration. In order to avoid that, additional solutions such as integrating heat-conductive materials into the PCM or increasing the surface area of the heat transfer could be used.
Santrauka
Siekiant efektyviai išnaudoti perteklinę, atliekinę ar atsinaujinančių energijos išteklių gaminamą energiją, vis dažniau taikomas fazinio virsmo medžiagų (FVM) panaudojimas pastato energetinėse sistemose. Kartu tai kelia naujus technologinius iššūkius pasirenkant konkrečias medžiagas, sistemų projektinius sprendinius, nes reikia gerai išmanyti šilumos mainų procesą vykstant fazės virsmui. Šiame darbe siekiama ištirti šilumos mainus šilumos kaupiklyje su fazinio virsmo medžiagomis naudojantis COMSOL Multiphysics programa. Analizės metu įvertintos medžiagos savybės vykstant fazės virsmui. Tai leido nustatyti, kad medžiagos šilumos laidumo koeficientas turi didelę reikšmę šilumos mainų intensyvinimui. Be to, atskirų taškų analizė tyrimo objekte atskleidė, kad per nagrinėjamąjį laikotarpį FVM paviršiniame sluoksnyje fazės virsmas neįvyksta. Siekiant to išvengti, galimi papildomi sprendimai, tokie kaip šilumai laidžių medžiagų integravimas į FVM arba šilumos mainų paviršiaus ploto didinimas.
Reikšminiai žodžiai: šilumos kaupimas, fazinio virsmo medžiaga (FVM), fazinio virsmo šiluma, šilumos mainai, skaitinis modeliavimas, COMSOL Multiphysics
Experimental and Theoretical Investigation of the Natural Convection Heat Transfer Coefficient in Phase Change Material (PCM) Based Fin-and-Tube Heat Exchanger
No full textLatent heat thermal energy storage systems allow storing large amounts of energy in relatively small volumes. Phase change materials (PCMs) are used as a latent heat storage medium. However, low thermal conductivity of most PCMs results in long melting (charging) and solidification (discharging) processes. This study focuses on the PCM melting process in a fin-and-tube type copper heat exchanger. The aim of this study is to define analytically natural convection heat transfer coefficient and compare the results with experimental data. The study shows how the local heat transfer coefficient changes in different areas of the heat exchanger and how it is affected by the choice of characteristic length and boundary conditions. It has been determined that applying the calculation method of the natural convection occurring in the channel leads to results that are closer to the experiment. Using this method, the average values of the heat transfer coefficient (have) during the entire charging process was obtained 68 W/m2K, compared to the experimental result have = 61 W/m2K. This is beneficial in the predesign stage of PCM-based thermal energy storage units.This article belongs to the Special Issue Energy Storage Systems and Conversion Processe
Investigation of the influence of mass flow rate on phase change material behaviour
No full textThe paper presents an experimental study of the influence of heat transfer fluid (HTF) mass flow rate on phase change materials (PCM) behaviour. The experimental study was performed on a specially designed test bench. Research object – PCM based thermal energy storage unit which consists of a stainless steel tank with dual circuit tube-fin copper heat exchanger. The tank (storage volume) was filled with phase change material RT82. The experiment was carried out using three different mass flow rates of HTF: high – 0.25 kg/s, medium – 0.125 kg/s, low – 0.05 kg/s. The analysis showed that in the case of high and medium mass flow rates the melting/solidification process highly depends on the temperature of inlet HTF. Influence of mass flow rate is higher in the case of low mass flow rate.
Article in Lithuanian.
Šilumnešio debito įtakos fazinio virsmo medžiagos veikimui tyrimas
Santrauka
Straipsnyje pateikiamas šilumnešio masės debito įtakos šilumai kaupti naudojamų fazinio virsmo medžiagų (FVM) veikimui eksperimentinis tyrimas. Tyrimas buvo atliekamas specialiai pagamintame testavimo stende. Tiriamasis objektas – FVM šilumos kaupimo įrenginys, sudarytas iš nerūdijančiojo plieno talpyklos ir dviejų kontūrų varinio šilumokaičio (vamzdelių) su varinėmis plokštelėmis. Talpykla užpildyta fazinio virsmo medžiaga RT82. Tyrimas atliekamas keičiant šilumnešio masinį debitą. Pasirinktos trys vertės: didžiausia – 0,25 kg/s, vidutinė – 0,125 kg/s ir mažiausia – 0,05 kg/s. Nustatyta, kad, esant didžiausiam ir vidutiniam debitams, FVM lydymosi / kietėjimo proceso trukmei didžiausią įtaką turi tiekiamojo šilumnešio temperatūra, esant mažiausiam debitui vyksta didesnė debito įtaka proceso trukmei.
Reikšminiai žodžiai: šilumos kaupimas, fazinio virsmo medžiaga (FVM), fazinio virsmo šiluma, šilumokaitis, šilumnešio srautas, testavimo stendas
- …
