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Investigation of Elastic and Dynamic Paper Properties
No full textBaigiamajame magistro darbe atliktas popieriaus elastinių bei dinaminių savybių teorinis bei eksperimentinis tyrimas. Teorinio tyrimo metu buvo nustatyti skirtingos struktūros popieriaus be rašalo dangos bei popieriaus, padengto dažų sluoksniu, savieji dažniai. Eksperimento metu buvo nagrinėjamos tų pačių popieriaus lapų elastinės savybės. Atliktas gautų rezultatų palyginimas Darbo apimtis - 57 lapai be priedų, 41 iliustracijos ir 24 lentelėsIn the final master thesis, theoretical and experimental research of elastic and dynamic properties of paper was performed. In the theoretical research, different structures of own frequencies has been identified of ink-free coated paper and ink-coated paper. In the experimental research, the dynamic and elastic properties of the same sheets of paper were analyzed. Comparison of the obtained results has been made. Thesis consists of 57 pages without appendixes, 41 pictures and 24 tables
Evaluation of biofiltration materials for H2S removal
No full textH2S concentrations in Biogas are limited by environmental regulations. Hence, there are multiple purification methods as biological filtration are developed to meet the standards. In a typical biofiltration process, a bed of organic or inorganic porous materials is forced through a humid gaseous stream that contains the H2S pollutant, because it helps microbial growth and serves as the deck for the bioprocess, and is the most important part of a biofilter and the whole process of Biogas purification from H2S. An ideal packing medium ought to possess a number of characteristics, including a high mechanical resistance, the capacity to provide essential nutrients to a diverse microbial population, a large buffer capacity, a suitable moisture-holding capacity, a high specific area, and high porosity. The physicochemical properties and H2S removal efficiency of the biochar, compost, expanded schist, and waste of cellular concrete will be discussed and compared in this study.Taip / Ye
The impact of Nordic foreign direct investment on innovation and knowledge transfer in the Baltic countries
No full textThe FDI from the Nordic countries dominate in the Baltic Countries. The Nordic companies invest in various business sectors including the industry and high-tech. Nordic countries are one of the leaders in innovation, patent, industry design and trademark registration. Internalization theories state that host countries benefit from the foreign capital due to “know-how”. The technology and knowledge transfer from the foreign capital companies are defined as even driving force for the economic growth. Thus, the aim of the article is to determine the impact of FDI from the Nordic countries on stimulation of innovations in the Baltic Countries and the interlinkages with the economic growth. The article applies, descriptive statistics and correlation-regression modelling. The findings of the research full fills the gaps in internalization and knowledge transfer theories
The influence of the construction of a shock absorber on damping characteristics
No full textBaigiamojo darbo tyrimų objektas yra automobilių pakabose naudojami vienvamzdžiai amortizatoriai ir šiuose amortizatoriuose esantys plokšteliniai vožtuvai. Darbe yra pateikiama tyrimo apžvalga ir pagrindimas. Remiantis jėgų metodo principais, sudaromas vienvamzdžio amortizatoriaus ir amortizatoriuose naudojamo plokštelinio vožtuvo matematinis modelis, skirtas nustatyti vožtuvo plokštelių deformacijas ir kontaktines jėgas, susidarančias amortizatoriaus eksploatacijos metu, nuo kurių priklauso amortizatoriaus sukuriamos slopinimo jėgos dydis ir slopinimo charakteristika. Aprašytas modelis pateikiamas programinio paketo „Matlab/Simulink“ aplinkoje. Modelio adekvatumo tikrinimas ir praktinio panaudojimo galimybės yra tiriamos specializuotu elektromechaniniu amortizatorių bandymų stendu atliekant eksperimentinius tyrimus, teoriniu ir eksperimentiniu būdais gautų rezultatų lyginimą ir analizę, pateikiamos darbo išvados. Darbą sudaro įvadas, 3 skyriai, išvados, literatūros sąrašas ir priedai. Magistro darbo apimtis – 95 lapai be priedų, 37 paveikslai, 15 lentelių, 76 literatūros šaltiniai, 3 priedai.The research object of this Master‘s thesis is the monotube shock absorbers used in the suspensions of vehicles and shim valves used in these shock absorbers. The review and grounding of the research is presented in the work. Based on the principles of the forces‘ method, a mathematical model of the monotube shock absorber and the shim valve used in the shock absorbers is designed for determining the deformations of valve shims and contact forces, which form during the exploitation of the shock absorber, that influence the value of damping force created by the shock absorbers and the damping characteristic. The described model is presented in the environment of software package “Matlab/Simulink“. The adequacy of the model is examined and the possibilities of practical use are researched by doing experimental tests using the specialised electromechanic shock absorber test stand, comparison and analysis of the results obtained through theoretical and experimental methods, and the work conclusions are presented. The work consists of introduction, 3 chapters, conclusions, bibliography and appendixes. The length of Master‘s thesis – 95 pages without appendixes, 37 figures, 15 tables, 76 sources of literature, 3 appendixes
Application of generalized linear mixed models in the repeated measures analysis
No full textBaigiamajame magistro darbe atlikta realių medicinos srities duomenų, surinktų pagal pakartotinių matavimų schemą, statistinė analizė, kurios tikslas – įvertinti cerebriniu paralyžiumi sergančių vaikų pakartotinio gydymo botulino injekcijomis efektyvumą. Teorinėje darbo dalyje pateikta išsami statistinių metodų, skirtų pakartotinių matavimų duomenims, apžvalga. Praktinėje dalyje, naudojant apibendrintųjų tiesinių modelių ir apibendrintųjų tiesinių mišriųjų modelių klasę bei programinį paketą R, sudaryti bei palyginti klasikiniai ir mišrūs binariniai logistiniai, ranginiai logistiniai bei tiesiniai mišrieji modeliai, įvertinantys taikyto gydymo efektyvumą atskiriems gydytų vaikų būseną nusakantiems požymiams. Darbą sudaro 5 dalys: įvadas, teorinė dalis, tiriamoji dalis, išvados, literatūra. Darbo apimtis – 59 p. teksto be priedų, 11 iliustracijų, 21 lentelė, 42 bibliografiniai šaltiniai. Atskirai pridedami darbo priedai.This thesis examines the medical data collected under the repeated measurements scheme. The main aim of the thesis is to evaluate the treatment efficiency of children with cerebral palsy. The theoretical part of the paper considers a detailed review about statistical methods for repeated measures data. In turn, in order to evaluate the treatment efficiency for separate indications for children, the models of classical and mixed binary logistic, classical and mixed ordinal logistic as well as linear mixed models were evaluated and compared in the practical part. The classes of Generalized Linear Models and Generalized Linear Mixed Models were being investigated. The data analysis and evaluation of models were performed using a software R . The thesis consists of: 59 p. text without appendixes, 11 pictures, 21 tables, 42 bibliographical entries. Appendixes included
On the study of ellipsoidal nanowire metamaterials for biomedical applications
No full textNanowire metamaterials play a pivotal role in a wide variety of applications including antennas research field and cancer detection in clinical practice. In the following we make a step forward by investigating properties of surface waves at the boundary of ellipsoidal nanowire metamaterial, specifically, we study effective properties of the ellipsoidal medium. The former could result in a possible application in clinical practice dealing with the cancer detection especially by having a deep insight into derived medium treatment approach due to the chosen model having similarities with the real biological systems containing cancer cells as the ellipsoidal inclusions. The future prospects could include translation of the obtained effective medium properties applying effective medium approximation models into cancer detection in clinical practice. The ultimate goal is to treat the investigated biological medium from the perspectives of the metamaterial theory.iss. 11vol. 5
Use of Long Persistent Phosphor in Energetics
No full textBaigiamajame magistro darbe analizuojamos ilgašvyčių fosforų spinduliuojamos šviesos trukmės priklausomybės nuo jų temperatūros bei sužadinimo laiko. Parodyta, kad Zn3Ga2Ge2O10:0,5%Cr3+ fosforas puikiai tinka šviesos surinkimui bei saugojimui. Nustatytos dvi charakteringos emisijos gesimo trukmės, sparčioji (šimtų milisekundžių eilės) ir lėtoji (šimtų sekundžių). Tiek šaldant fosforą, tiek ir ilginant jo apšvitos laiką, abi trukmės ilgėja. Tai rodo, kad šio fosforo sukauptą šviesos energiją galima akumuliuoti ir panaudoti vėliau norimu laiku. Darbą sudaro 5 dalys: įvadas, literatūros apžvalga, tyrimų metodika, rezultatai ir jų analizė, išvados ir rekomendacijos, literatūros sąrašas. Darbo apimtis – 36 p. teksto be priedų, 21 iliustr., 6 lent., 22 bibliografiniai šaltiniai.The master thesis analyzes dependence of persistent phosphor emission duration on temperature and time of excitation. It is shown that Zn3Ga2Ge2O10:0,5%Cr3+ phosphorous is perfect for light accumulation and storage. Two characteristic emission decay time constants, fast (hundreds of milliseconds) and a slow (hundreds of seconds) have been determined. Cooling of the phosphorus as well as longer excitation time cause increase of the both time constants. This shows that light energy accumulated by the phosphorus can be stored and then used at desired time. The work consists of 5 sections: introduction, literature review, experimental, results and discussion, conclusions and recommendations and list of references. Thesis consists of 36 pages of text without appendixes, 21 figures, 6 tables, 22 positions in list of references
Mokslo institucijų MTTP veiklos integravimo į pramonės įmonių veiklą gerinimas
No full textIn this Master‘s degree Thesis a problem of collaboration difficulties between scientific institutions and industrial enterprises is analysed. Current literature on the subject and current situation of the subject is reviewed and assessed. Research was done to assess the possitive impact of R&D and innovations to industrial companies and confirm the need for collaboration. Data from Lithuanian, Estonian and Latvian countries was evaluated. Further research was mainly done usig data gathered from Lithuanian industry companies. Research was conducted using quantitative research methods and statistical data analysis. Structure: Introduction, Literature review and assessement of current situation, Research and result analysis, Concept model presentation, Model implementation, Possible future of the model, Conclusions, References, Annexes. Volume of thesis – 65 p., 23 pictures, 2 tables, 50 referenceBaigiamojo darbo temoje nagrinėta pramonės įmonių ir mokslo institucijų bendradarbiavimo sunkumų problema. Buvo apžvelgta ir išanalizuota literatūra šia tema bei įvertinta dabartinė situacija. Tyrimų tikslas buvo įvertinti teigiamą MTEP ir inovacijų naudą pramonės įmonėms ir patvirtinti poreikį bendradarbiavimo vystymui. Įvertinti Lietuvos, Latvijos ir Estijos pramonės įmonių duomenys. Tolimesnis tyrimų etapas buvo atliekamas surenkant informaciją iš Lietuvos pramonės įmonių ir apdorojant rezultatus statistiniais metodais. Struktūra. Įvadas, Literatūros apžvalgą, analizė ir dabartinės situacijos vertinimas, Tyrimai ir rezultatų analizė, Koncepcinio modelio pristatymas, Modelio įdiegimas, Modelio ateities plėtros planai, Išvados, Literatūros sąrašas, Priedai. Baigiamojo darbo apimtis - 66 p., 23 paveikslėliai, 2 lentelės, 51 literatūros šaltinis
The research of pipeline residual strength
No full textDarbe nagrinėjama magistralinių dujotiekių mechaninių pažeidimų įtaka saugiam jų eksploatavimui. Įmonėms, prižiūrinčioms magistralinius dujotiekius Lietuvoje ir kitose pasaulio šalyse, ši problema yra aktuali ir šiuo metu kelianti problemų. Atlikta literatūros apžvalga, pagal kurią susisteminta informacija apie pagrindinius mechaninius pažeidimus, jų būdingus bruožus ir įtaką vamzdyno eksploataciniams parametrams. Kiekvienam pažeidimui pasiūlytas esamas analizės metodas. Ištirta magistralinio dujotiekio Kaunas–Kaliningradas dalis, kuri buvo pašalinta kaip neatitinkanti eksploatacinių parametrų. Tyrimams naudotas kietumo matavimas, smūginio tąsumo bandymas, mikrostruktūros tyrimas pasitelkiant optinį mikroskopą. Taip pat tiriamasis objektas buvo atkurtas kompiuterinės programos, veikiančios baigtinių elementų metodu, „Ansys“ erdvėje. Darbą sudaro įvadas, literatūros apžvalga, atlikti eksperimentai, išvados ir literatūros sąrašas. Darbo apimtis – 56 puslapių aiškinamasis raštas be priedų.The paper examines the transmission pipeline mechanical damage influence for the safe operation. For businesses, supervising the main gas pipeline in Lithuania and other countries of the world are affected and are currently posing problems. Was performed the literature review in which systematic information on major mechanical damage, their attributes and the influence of the operating parameters of the pipeline. For each damage type was proposed current method of analysis. Was made investigation of the main gas pipeline Kaunas-Kaliningrad, part of which was removed to fulfill the operational parameters. Research used hardness measurement, impact testing, microstructure study using an optical microscope. As well as the research object has been restored to a computer program, operating in the finite element method, in ANSYS environment. Structure: introduction, literature review, experiments, conclusion and references. Thesis consist of: 56 p. text without appendixes, 44 pictures, 8 tables, 29 bibliographical entries. Appendixes included
Leveraging digital learning and work-based learning to enhance employee skills in small and medium enterprises
No full textSmall and medium enterprises (SMEs) play a critical role in the European economy, accounting for the majority of businesses and employment opportunities. However, with rapidly changing technology and global competition, it is becoming increasingly important for SMEs to stay competitive. This paper explores the role of digital learning and work-based learning (WBL) in helping European SMEs remain competitive in the 21st century. Digital learning and work-based learning are two of the most innovative and influential approaches to education and training in the 21st century. Both approaches leverage technology and real-world experience to help students and workers acquire the skills they need to succeed in their careers. The paper argues that by leveraging technology and real-world experience, SMEs can upskill their employees and stay ahead of the curve. The paper concludes that a combination of digital learning and work-based learning has the potential to transform the way SMEs approach employee development, allowing them to remain competitive in a rapidly changing business landscape. This paper utilizes a mixed-methods approach, incorporating both a literature review and the results of a survey, to explore the role of digital learning and work-based learning.Taip / YesI