Vilnius Gediminas Technical University
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Pro-Environmental Energy Behavior in the Military: Assessing Behavior Change Factors at a Selected Military Unit
No full textThe purpose of this study is to explore how pro-environmental energy behavior is manifested at a military unit and what behavioral change factors can enhance such behavior. The military unit represents an organization dominated by an exceptionally strong sense of community and belonging where individual pro-environmental energy behavior goes in line with a collective one. The application of Capability-Opportunity-Motivation-Behavior (COM-B) approach led to a better understanding of energy-saving behavior in the military as an organization where personnel are trained to increase their awareness of their peers’ behavior. Methods: The results were obtained using data collected from two independent samples of both professional soldiers and conscripts at a military unit of Lithuanian defense forces located in a fixed installation in the time frame of 2018–2019. The total sample of respondents (professional soldiers and conscripts) was N = 454. A series of statistical tests were performed at the 0.05 level of confidence. Results: An extended COM-B model for the analysis of pro-environmental energy behavior in the military was proposed and applied. The results show that the three behavioral change factors—capability, opportunity, and motivation—are first of all positively linked with the collective energy behavior at the military unit and only then with the individual soldier’s pro-environmental energy behavior. This is a new insight into the COM-B model as collective and individual behavior are identified as separate indicators and then combined into a single measurable construct. In addition, the results indicate that in the military unit, communality plays an important role in sustaining pro-environmental energy behavior, even if an individual behavior indicates low-involvement.This article belongs to the Special Issue Innovation in Energy Security and Long-Term Energy Efficienc
Compact Square-Wave Pulse Electroporator with Controlled Electroporation Efficiency and Cell Viability
No full textThe design and development of a compact square-wave pulse generator for the electroporation of biological cells is presented. This electroporator can generate square-wave pulses with durations from 3 μs up to 10 ms, voltage amplitudes up to 3500 V, and currents up to 250 A. The quantity of the accumulated energy is optimized by means of a variable capacitor bank. The pulse forming unit design uses a crowbar circuit, which gives better control of the pulse form and its duration, independent of the load impedance. In such cases, the square-wave pulse form ensures better control of electroporation efficiency by choosing parameters determined in advance. The device has an integrated graphic LCD screen and measurement modules for the visualization of the current pulse, allowing for express control of the electroporation quality and does not require an external oscilloscope for current pulse recording. This electroporator was tested on suspensions of Saccharomyces cerevisiae yeast cells, during which, it was demonstrated that the application of such square-wave pulses ensured better control of the electroporation efficiency and cell viability after treatment using the pulsed electric field (PEF).This article belongs to the Special Issue Information Technologies and ElectronicsThis work was partly funded by “Geozondas” Ltd. Implementing an EU structural investment project
01.2.1-MITA-T-851-02-0004 under measure “Inocekiai.
Effect of Laser Processing on Surface Properties of Additively Manufactured 18-Percent Nickel Maraging Steel Parts
No full textIn the present work, the experimental study on laser processing of additively manufactured (AM) maraging steel part surface was conducted. Nanosecond pulsed laser at ablation mode was used for surface modification in oxidizing atmosphere. The morphology, roughness, elemental and phase composition, microhardness and tribological properties of the processed surfaces were investigated. The obtained results revealed that pulsed laser processing under the ablation mode in air allows obtaining modified surface with uniform micro-texture and insignificant residual undulation, providing 3 times lower roughness as compared with the as-manufactured AM part. The intensive oxidation of surface during laser processing results in formation of the significant oxides amount, which can be controlled by scanning speed. Due to the presence of the oxide phase (such as Fe2CoO4 and Ti0.11Co0.89O0.99), the hardness and wear resistance of the surface were significantly improved, up to 40% and 17 times, respectively. The strong correlation between the roughness parameter Ra and mass loss during the tribological test testifies the significant role of the obtained morphology for the wear resistance of the surface.This article belongs to the Section Surface Characterization, Deposition and Modificatio
Design of Unimorph Type 3DOF Ultrasonic Motor
Get PDFA new design of 3 degrees of freedom (DOF) piezoelectric ultrasonic motor (USM) is introduced in this paper. The concept of this design is to incorporate a spherical rotor between two piezoelectric transducers. Each transducer is coupled with a flange, and it operates like a unimorph structure. Such a design of the transducer allows to increase the amplitude of the vibrations and to generate the higher torque and driving force used to achieve 3DOF rotary motion of the spherical rotor. The proposed USM may be used for humanoid robots, optomechanical systems, or small satellites. This USM consists of several components, is lightweight and reliable. Numerical analysis and experimental studies were performed to validate the feasibility of this drive, to find out proper resonant frequencies for the unimorph, and optimize the shape of the flange. Experimental studies were accomplished to validate the results of the numerical analysis and to validate the operating principles of the piezoelectric motor.This article belongs to the Special Issue Ultrasonic Transducers and Related Apparatus and ApplicationsThis research was funded by the European Regional Development Fund under a grant agreement with
the Research Council of Lithuania, grant number 01.2.2-LMT-K-718-01-0010
Inferring Effective Population Size and Divergence Time in the Lithuanian Population According to High-Density Genotyping Data
Get PDFThe prehistory of the Lithuanian population and genetic relationship to other populations are poorly studied. Thus, the Lithuanian population, as an object of study, is interesting due to its partial isolation with genetic distinctiveness within the European context and with preserved ancient genetic composition. The main objects of this study was to infer demographic parameters, effective population size (Ne), and divergence time using high-density single nucleotide polymorphism (SNP) genotyping data generated with the Illumina HumanOmmiExpress-12v1.1 array in 295 individuals from the Lithuanian population and to compare our data with other populations from the Human Genome Cell Line Diversity Panel (HGDP-CEPH). We also aimed to reconstruct past events between the main ethnolinguistic regions—Aukštaitija and Žemaitija of Lithuania. Historically, these regions probably developed as two independent Baltic tribes. Our results of Ne in the Lithuanian population through time demonstrated a substantial reduction of Ne over the 150,000–25,000 years before present (YBP). The estimated long-term Ne of the Lithuanian population is quite low—it equals 5404, which likely is a consequence of the bottlenecks associated with the last glacial period of 25,000–12,000 YBP in Europe. The obtained divergence time estimates between the study populations are in agreement with recent studies. The reconstructed past events in Aukštaitija and Žemaitija showed significant differences between these two regions of Lithuania.This article belongs to the Section Population and Evolutionary Genetics and GenomicsThis work was supported by the Research Council of Lithuania, grant no. S-MIP-20-07
Strong Coupling between Tamm and Surface Plasmons for Advanced Optical Bio-Sensing
No full textThe total internal reflection ellipsometry method was used to analyse the angular spectra of the hybrid Tamm and surface plasmon modes and to compare their results with those obtained using the conventional single SPR method. As such type of measurement is quite common in commercial SPR devices, more detailed attention was paid to the analysis of the p-polarization reflection intensity dependence. The conducted study showed that the presence of strong coupling in the hybrid plasmonic modes increases the sensitivity of the plasmonic-based sensors due to the reduced losses in the metal layer. The experimental results and analysis of the optical responses of three different plasmonic-based samples indicated that the optimized Tamm plasmons ΔRp(TP) and optimized surface plasmons ΔRp(SP) samples produce a response that is about five and six times greater than the conventional surface plasmon resonance ΔRp(SPR) in angular spectra. The sensitivity of the refractive index unit of the spectroscopic measurements for the optimized Tamm plasmon samples was 1.5 times higher than for conventional SPR, while for wavelength scanning, the SPR overcame the optimized TP by 1.5 times.This article belongs to the Special Issue Thin Films and Surface Optic
Planning development of construction by taking into account interests of the third parties
No full textDisertacijoje nagrinėjamos statybų plėtros planavimo, įvertinant trečiųjų asmenų interesus, problemos. Pagrindiniai tyrimo objektai yra teisinė investicinio statybos proceso reglamentavimo bazė; teritorijų planavimo teisiniai pažeidimai, planuojant statybos investicijas; pažeistų trečiųjų asmenų teisių gynimo proceso, įgyvendinant investicinius statybos projektus, modeliavimas; statybos planavimo sprendimų matematinis modeliavimas. Šie objektai yra svarbūs įgyvendinant statybos projektą, nes teisminio ginčo atsiradimas yra nepageidaujamas rizikos veiksnys, galintis sužlugdyti visą projektą.
Disertacijos tikslas – statybos planavimo sprendimų modeliavimas, įvertinant trečiųjų asmenų interesus, siekiant sumažinti teisminio ginčo atsiradimo riziką, įgyvendinant statybos investicinį projektą.
Disertaciją sudaro įvadas, keturi skyriai, rezultatų apibendrinimas, naudotos literatūros sąrašas, autorės publikacijų disertacijos tema sąrašas ir 3 priedai.
Įvade aptariama tiriamoji problema, darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas ir uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas, ginamieji teiginiai.
Kiekviename skyriuje apžvelgiama ir analizuojama mokslinė bei metodinė literatūra, atitinkanti kiekvieno skyriaus tematiką.
Pirmajame disertacijos skyriuje sprendžiamos sveikos ir harmoningos gyvenamosios bei darbo aplinkos išsaugojimo miestų plėtros metu problemos.
Antrajame disertacijos skyriuje nustatyti trečiųjų asmenų teisių pažeidimai, plėtojant statybas. Sudarytas trečiųjų asmenų teisių pažeidimų klasifikatorius. Suformuluota trečiųjų asmenų teisių pažeidimų samprata.
Trečiajame disertacijos skyriuje atliktas ginčo proceso dėl galbūt pažeistų trečiųjų asmenų teisių modeliavimas, taikant sprendimų medžio diagramą.
Ketvirtajame disertacijos skyriuje atliktas statybos planavimo sprendimų modeliavimas, įvertinant trečiųjų asmenų interesus, t. y. parengtas matematinis modelis asmens, investuojančio į statybas ir susiduriančio su visuomenės pasipriešinimu, siekiančio maksimalaus pelno galimoms elgesio strategijoms įvertinti. Sukurtas optimalių strategijų radimo uždavinys, naudojant daugiažingsnį optimizavimą, t. y. stochastinį dinaminį programavimą.
Disertacijos pabaigoje pateikiamos išvados ir literatūros šaltinių sąrašas.
Disertacijos tema paskelbti šeši moksliniai straipsniai: trys – mokslo žurnaluose, referuojamuose Mokslinės informacijos instituto (ISI) duomenų bazėse (ISI Web of Science leidiniuose); du – mokslo žurnaluose, referuojamuose kitose tarptautinėse duomenų bazėse, ir vienas – kituose leidiniuose. Disertacijos tema perskaityti trys pranešimai mokslinėse konferencijose Lietuvoje.Daktaro disertacij
Valuation of FinTech Innovation Based on Patent Applications
No full textThe financial services sector, perhaps more than any other, is being disrupted by advances in technology. The purpose of this study is to provide comprehensive data and evidence on value of the FinTech innovation event. First, a text-based filtering method for identifying FinTech patent applications is provided. Using machine learning applications, innovations are classified into major technology groups. The methodology for valuation of FinTech innovation is based on data of stock price changes. To assess the value impact, Poisson flow rates and stock price movements were combined. Further, to evaluate the effect of FinTech patents on the company’s value, a combination of CAR of patent application and Poisson intensities were used. Research findings provide evidence that FinTech innovations bring significant value for innovators and Blockchain being especially valuable. Such innovations as blockchain, robo-advising and mobile transactions are the most valuable for the financial sector. On one side of the spectrum, the financial industry can be affected more negatively by the innovation of nonfinancial startups that carry disruptive technology at their core. However, on the other side of the spectrum, market leaders who make significant investments in their innovations can evade most of these negative effects. This helped to form an overall view of FinTech innovations.This article belongs to the Special Issue Sustainability, Digital Transformation and Fintech: The New Challenges of the Banking Industr
Investigation of Position and Velocity Stability of the Nanometer Resolution Linear Motor Stage with Air Bearings by Shaping of Controller Transfer Function
No full textModern industrial enterprises require high accuracy and precision feedback systems to fulfil cutting edge requirements of technological processes. As demand for a highly accurate system grows, a thin gap between throughput and quality exists. The conjunction of ultrafast lasers and modern control strategies of mechatronic systems can be taken into account as an effective solution to reach both throughput and tolerances. In the present paper, the dynamic errors of the moving platform of the one degree of freedom stage, based on linear motor and air bearings, have been analyzed. A precision positioning system is investigated as a symmetric system which is based on symmetric linear motor. The goal of the present article is to investigate the controllers of the different architecture and to find the best controller that can ensure a stable and small dynamic error of the displacement of the stage platform at four different constant velocities of the moving platform. The relations between the controller order, velocity and the displacement dynamic error have been investigated. It is determined that higher-order controllers can reduce the dynamic error significantly at low velocities of the moving platforms: 1 and 5 mm/s. On the contrary, the low order controllers of 4th-degree polynomials of the transfer function can also provide small dynamic errors of the displacement of the platform.This article belongs to the Special Issue Symmetry in Optimization and Control with Real World Application
Discrete road traffic flow research method to determine the instantaneous noise level on the streets
Get PDFDisertacijoje nagrinėjami gatvių transporto srautai (TS) ir jų skleidžiamas triukšmo lygis (TL). Pagrindinis tyrimo objektas yra kelių transporto srautų gatvėse, jas supančios aplinkos ir transporto priemonių skleidžiamo momentinio triukšmo lygio sąveika. Triukšmas, viršijantis normas, kuris sklinda nuo TP, yra vienas svarbiausių veiksnių, turinčių neigiamą įtaką eismo dalyvių bei netoli gatvių esančių (gyvenančių, dirbančių, besimokančių, poilsiaujančių, besigydančių...) žmonių sveikatai, poilsiui, jis trukdo darbui. Išsami TS ir jo skleidžiamo triukšmo lygio analizė leidžia nustatyti TS dinaminių procesų įtaką triukšmo lygiui bei galimas tinkamas priemones jam sumažinti. Disertacijos tikslas – patobulinti diskretinį transporto srauto tyrimo metodą, leidžiantį įvertinti jų dinaminius procesus, turinčius įtakos skleidžiamam momentiniam triukšmo lygiui miesto gatvėse.
Disertacijoje nagrinėjamas šviesoforų signalų valdymo bei eismo įvykio įtaka TS dinaminiams procesams taikant patobulintą diskretinį transporto srauto tyrimo metodą (DTSTM). Transporto srauto skleidžiamas momentinis triukšmo lygis nustatomas įvertinant patobulinto diskretinio transporto srauto tyrimo metodo gautus rezultatus ir eksperimentinius triukšmo lygio duomenis, įvertinančius kelio dangos būklę, transporto priemonių važiavimo greitį ir kategoriją.
Disertaciją sudaro įvadas, keturi skyriai, bendrosios išvados, literatūros ir autoriaus publikacijų disertacijos tema sąrašai ir keturi priedai.
Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas bei uždaviniai, nurodomi tyrimų metodai ir įranga, 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 apžvalgai. Jame pateikti kitų tyrėjų duomenys ir rezultatų reikšmė transporto srautų bei triukšmo tyrimuose. Skyriaus pabaigoje formuluojamos išvados ir tikslinami disertacijos uždaviniai.
Antrajame skyriuje pateiktas patobulintas diskretinis transporto srauto tyrimo metodas ir sukurta momentinio triukšmo lygio tyrimo metodika.
Trečiajame skyriuje pateikti transporto srautų dinaminių procesų ir jų skleidžiamo triukšmo eksperimentinių tyrimų rezultatai.
Ketvirtajame skyriuje pateikta transporto srauto parametrų įtakos momentiniam triukšmo lygiui teorinio modeliavimo rezultatų analizė.
Disertacijos tema paskelbti 7 straipsniai: vienas – straipsnių rinkinyje, įtrauktame į Clarivate Analytics Web of Science duomenų bazę, du – recenzuojamame mokslo žurnale, du – tarptautinių konferencijų leidiniuose, referuojamuose Clarivate Analytics duomenų bazėje Proceedings, du – tarptautinės konferencijos leidinyje. Disertacijos tema perskaityti 4 pranešimai tarptautinėse konferencijose.Disertacij