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Design and production by additive technologies and research of inertia sensors
No full textBaigiamajame darbe atlikta inercinių daviklių panaudojimo apžvalga ir esamų konstrukcijų analizė. Pasiūlyti 2D ir 3D tipo inerciniai davikliai ir sukurti veikiantys pavyzdžiai. Pasiūlyta 2D inercinių daviklių gamybos technologija masinei gamybai. Atlikti 3D inercinių daviklių įvairių storių kontaktų stipruminiai bandymai. Nustatyti 3D inercinių daviklių kritiniai metimo aukščiai naudojant suprojektuotą laisvo kritimo stendą. Bandymai buvo filmuoti naudojant greitaeigę vaizdo kamerą. Palyginti eksperimentinių ir skaičiuojamųjų įtempimų rezultatai. Darbą sudaro 7 dalys: įvadas, sukurtų inercinių daviklių apžvalga, darbe siūlomi inerciniai davikliai, tyrimai, išvados ir pasiūlymai, literatūros sąrašas, priedai. Darbo apimtis: 52 psl. teksto be priedų, 40 iliustracijų, 29 lentelių, 22 bibliografinių šaltinių. Atskirai pridedami darbo priedai.The final Master thesis includes an overview of the use of inertial sensors and analysis of existing designs. Proposed 2D and 3D type inertial sensors and made working examples. The technology for producing 2D inertia sensors for mass production is proposed. Strength tests of various thickness contacts of 3D inertial sensors were performed. Critical throwing heights of 3D inertia sensors were determined using a designed free fall stand. The tests were filmed using a high-speed camera. The results of experimental and computational stress were compared. Master thesis consists of 7 parts: introduction, overview of created inertial sensors, inertial sensors, research, conclusions and suggestions, references, appendixes. Master thesis consists of 52 p. text without appendixes, 40 pictures, 29 tables, 22 bibliographical entries. Appendixes are included separately
Managerial opportunities in application of business intelligence in construction companies
No full textIn construction projects, managers make multiple decisions every day. Most of these decisions are relatively unimportant; some of them are critical and could lead to the success or failure of a construction project. To ensure construction companies make effective managerial decisions, decision making requires performing an initial technical and economic analysis, comparing different decision-making solutions, using a planning system, and ensuring project implementation based on the provided plans. Therefore, the use of powerful systems such as business intelligence (BI), which play a central role in management and decision-making, is essential in project-based companies. The current study aims to determine and evaluate the main managerial opportunities in the application of BI in project-based construction companies using a descriptive survey approach. An empirical research questionnaire consisting of 60 factors and 7 categories was adopted. The questionnaire, after confirming its validity and reliability, was distributed to 100 experts engaged in 5 active project-based construction companies who were familiar with BI topics. To analyse the data, a one-sample t-test and the Friedman test were performed using the SPSS software. The findings indicated that the importance of the identified opportunities for the use of BI in project-based construction companies is above average and that, in the case of using BI in such companies, these opportunities can be used to improve project performance. The results of the current study can help managers and other stakeholders as an effective decision-making tool to better implement BI in project-based companies.iss. 6vol. 2
Stimulation of Human Mesenchymal Stem Cell Chondrogenic Differentiation Applying Electroconductive Polymers
No full textŠiame tyrime nagrinėjamas polipirolo (Ppy) ir polipirolo su aukso nanodalelėmis (Ppy/Au) poveikis žmogaus mezenchiminių kamieninių ląstelių (MKL) chondrogeninei diferenciacijai in vitro. MKL yra daugiagalės kamieninės ląstelės, gebančios diferencijuoti į įvairių audinių ląsteles, įskaitant adipocitus, osteoblastus ir chondrocitus. Šios ląstelės yra naudojamos kaulinių ir kremzlinių audinių inžinerijoje bei regeneracinėje medicinoje. Sąnario kremzlė, kuri yra sunkiai pažaidas atstatantis audinys ir turinti polinkį į osteoartritą, yra tyrimų objektas. Kadangi nėra efektyvių osteoartritą gydančių vaistų, bandoma taikyti kamieninių ląstelių terapijas, naudojant MKL su elektrai laidžių polimerų pagalba. Vienas iš populiariausių elektrai laidžių polimerų biomedicinoje yra Ppy, kuris gali būti gaminamas karkasų ar mikro- ir nanodalelių formomis. Ppy pasižymi geru biosuderinamumu, lankstumu ir stabilumu bei yra naudojamas vaistų ir baltymų pernašai. Elektrinė stimuliacija su Ppy struktūromis rodo teigiamą poveikį ląstelių funkcijoms ir jų diferenciacijai. Šiame tyrime siekiama išsiaiškinti Ppy ir Ppy/Au poveikį MKL chondrogeninei diferenciacijai in vitro, įvertinant jų įtaką augimo veiksnių ir užląstelinio užpildo sintezei bei viduląstelinio kalcio jonų koncentracijos pokyčiui. Tyrimo rezultatai rodo, kad Ppy ir Ppy/Au stiprina chondrogeninį atsaką MKL ir chondrocitų ląstelėse, o elektrinė stimuliacija papildomai skatina šį procesą. Šie rezultatai suteikia naujų žinių apie Ppy ir Ppy/Au naudojimą chondrogeninės diferenciacijos in vitro metu, taip pat patvirtina elektrinės stimuliacijos potencialą naudojant Ppy ir Ppy/Au chondrogeninei diferenciacijai skatinti. Darbą sudaro aštuonios dalys: įvadas, literatūros apžvalga, metodai, rezultatai ir jų aptarimas, išvados, literatūros sąrašas, padėka ir priedai. Darbo apimtis – 53 p. teksto be priedų, 20 iliustr., 2 lent., 51 bibliografiniai šaltiniai. Atskirai pridedami darbo priedai.This study investigates the effect of polypyrrole (Ppy) nanoparticles and polypyrrole nanoparticles with gold (Ppy/Au) on the chondrogenic differentiation of human mesenchymal stem cells (MSCs) in vitro. MSCs are multipotent stem cells capable of differentiating into various cell types, including adipocytes, osteoblasts, and chondrocytes. These cells have been widely used in bone and cartilage tissue engineering and regenerative medicine. The focus of this research is on the articular cartilage, a tissue with limited self-healing capacity and commonly affected by osteoarthritis (OA). Given the lack of effective pharmacological treatments for OA, stem cell therapies using MSCs are being explored. Polypyrrole, an electrically conductive polymer widely used in biomedicine, is studied in this context. Ppy can be synthesized as layers or micro- and nanoparticles in neutral aqueous solutions. It exhibits excellent biocompatibility, flexibility, and stability and has been shown to facilitate drug delivery and promote the proliferation and differentiation of neurons and stem cells. However, the application of Ppy nanoparticles in promoting chondrogenic differentiation of MSCs has not been previously investigated. Therefore, this study presents novel findings regarding the potential effects of Ppy and Ppy/Au on the chondrogenic differentiation of MSCs, both in the absence and presence of electrical stimulation. The research demonstrates the biocompatibility and viability of MSCs and chondrocytes with Ppy nanoparticles. Additionally, the combination of Ppy and electrical stimulation enhances the synthesis of growth factors and extracellular matrix, as well as increases intracellular calcium ion secretion. Overall, the research highlights the potential of Ppy and Ppy/Au nanoparticles in promoting chondrogenic differentiation. The thesis consists of 53 p. text without appendices, 20 pictures, 2 tables, and 51 bibliographical entries. Appendices are included
Detection of Malicious Code Using an Immune System Model
No full textBaigiamajame magistro darbe pritaikomas biologinės imuninės sistemos modelis, skirtas informacijos ir informacinių sistemų saugos, kenksmingam programiniam kodui atpažinti. Visų pirma atliekamas teorinis tyrimas: surenkama ir išanalizuojama susijusi informacija ir išskiriami labiausiai šiam darbui tinkantys dirbtinės imuninės sistemos algoritmai. Pagal išanalizuotą informaciją parengiamas modelio projektas, kuris sudarytas iš duomenų gavybos, negatyvios atrankos ir klonavimo atrankos veikimo principų ir darbo eigos aprašymo. Toliau vykdomas praktinis modelio realizavimas, o naudojami parametrai aprašomi šiame darbe. Gauti rezultatai apibendrinami, pateikiami komentarai, įžvalgos bei galimi tolimesni darbai. Bendras, vidutinis modelio tikslumas klasifikuojant anomalijų turinčius duomenis - 67,4%, anomalijų neturinčius duomenis - 67,9%. Dokumento apimtis - 54 psl., be priedų, 25 iliustracijos, 9 lentelės, 18 bibliografinių šaltinių.The model of the biological immune system is applied in the final master's thesis to identify malicious software code for information and information systems security. In particular, a theoretical study is carried out: relevant information is collected and analyzed, and the most suitable algorithms of the artificial immune system are singled out. Based on the analyzed information, a draft model is prepared, which consists of a description of the operating principles and workflow of data mining, negative selection and cloning selection. The practical implementation of the model is continued, and the parameters used are described in this work. The obtained results are summarized, comments, insights and possible further work are provided. The overall, average accuracy of the model in classifying malware data was 67.4%, and data without anomalies were 67.9%. The volume of this document is 54 pages, without appendixes, 25 illustrations, 9 tables, 18 bibliographical entries
Web page content block identification with extended block properties
No full textWeb page segmentation is one of the most influential factors for the automated integration of web page content with other systems. Existing solutions are focused on segmentation but do not provide a more detailed description of the segment including its range (minimum and maximum HTML code bounds, covering the segment content) and variants (the same segments with different content). Therefore the paper proposes a novel solution designed to find all web page content blocks and detail them for further usage. It applies text similarity and document object model (DOM) tree analysis methods to indicate the maximum and minimum ranges of each identified HTML block. In addition, it indicates its relation to other blocks, including hierarchical as well as sibling blocks. The evaluation of the method reveals its ability to identify more content blocks in comparison to human labeling (in manual labeling only 24% of blocks were labeled). By using the proposed method, manual labeling effort could be reduced by at least 70%. Better performance was observed in comparison to other analyzed web page segmentation methods, and better recall was achieved due to focus on processing every block present on a page, and providing a more detailed web page division into content block data by presenting block boundary range and block variation data.iss. 9vol. 1
The role of East Asia in current issues focus on value chain management of logistics and transport market
No full textCharacter of China modern supply chain circumstance accentuated, essential value logistics features outlined. Principally the main attention in research issues are focused on concept of empirical analysis of China logistics value, the criteria for evaluation the technological development supply chain management and economic impact assessment for a dynamic system, compilation of a survey questionnaire procurement processes specialists, identification respondents groups, monitoring SWOT and PESTL analysis production chain process, investigation analysis distribution systems documents, mathematical statistical study value chain MANOVA research and evaluation of logistics management strategic business trends. Findings and contribution of this article presented, outlined that East Asia value chain transportation management in the supply chain transportation system is very important topic for future research analysis. It is found that value chain transportation management is a flexible and in high level organized in their different logistics processes
Gainers and losers of euro adoption: the case of the Baltic states
No full textIn this paper we analyse the effects of the adoption of euro on the economies of the three Baltic countries. We employ the difference-in-differences approach to estimate the impact of the currency changeover on the product prices in the Baltic states. We also examine which specific demographic groups of consumers (by their age, education and income levels) were the most sensitive for the currency changeover. Our results suggest that the greatest euro-related price increase in the Baltic countries was related to the products belonging to the 4th and the 5th price quantiles, especially services. We also find that in the Baltic countries consumers groups which reacted to the adoption of euro the most sensitively were better educated people between 30 and 49 years. However, the impact of currency changeover for the consumers seems to be country specific.Taip / Yes
Evaluation of Augmented Reality Commerce Apps in Terms of Use Experience
No full textBaigiamajame magistro darbe nagrinėjama papildytos realybės komercinių mobiliųjų programėlių vertinimo vartotojo patirties atžvilgiu problematika. Išnagrinėjus mokslinę literatūrą pateikta papildytos realybės apibrėžtis, samprata, išanalizuotas jos sektorius pasaulyje ir Lietuvoje, nagrinėjami šios technologijos komunikaciniai aspektai ir taikymas komerciniuose procesuose, taip pat analizuota mobilioji papildyta realybė ir jos programėlės bei šios technologijos kuriamo informacinio proceso vertinimo metodai. Pasitelkus UEQ metodą, buvo įvertinta papildytos realybės mobiliųjų programėlių „Inkhunter“ ir „Arilyn“ vartotojo patirtis, atliktas ekspertinis vertinimas. Pagal gautus tyrimo rezultatus suformuoti siūlymai vertintų programėlių gerinimui ir gairės naujų papildytos realybės mobiliųjų programėlių kūrimui. Darbą sudaro 6 dalys: įvadas, 3 dalys teksto, išvados ir literatūros sąrašas. Darbo apimtis – 72 p. teksto be priedų, 25 pav., 6 lent. ir 78 bibliografiniai šaltiniai. Atskirai pridedami darbo priedaiIn this final master thesis evaluation of augmented reality mobile apps in terms of user experience problem is analyzed. By analyzing scientific literature, augmented reality definitions and concept are presented, its sector in the world and Lithuania are reviewed. Adding to that, augmented reality communicative aspects, application in commerce processes as well as mobile augmented reality, its apps and evaluations methods are analyzed. By using UEQ method, augmented reality mobile apps “Inkhunter” and “Arilyn” were evaluated in terms of user experience, also expert evaluation were conducted. According to results of the research, recommendations for evaluated apps and guidelines for new augmented reality apps creation were presented. Structure: introduction, 3 parts of the text, conclusions and references. Thesis consists of: 72 pages of text without appendixes, 25 pictures, 6 tables, 78 bibliographic entries. Appendixes are included
Analysis of Agile Methods Usage in Information Security Audit Process
No full textDarbe analizuojamas informacijos saugos audito procesas ir „Agile“ metodo pritaikymo galimybės tobulinti tradicinį informacijos saugos audito procesą. Teorinėje darbo dalyje pateikiami tradicinio informacijos saugos metodo etapai, jų sugretinimas su Krioklio metodu, taikomu valdant projektus. Tradicinio metodo analizė atskleidė šio metodo trūkumus, tokius kaip, detalus audito planavimas jau audito pradžioje, ar vengimas keisti audito planą audito metu. Bandymai optimizuoti šį metodą tik iš dalies sprendžia šias problemas, iki šiol nesiūlyta metodo transformacija. „Agile“ metodo analizė patvirtino šio metodo taikymo informacijos saugos audito procese prielaidas, siekiant jį atlikti efektyviau. Praktinėje dalyje pasiūlomas patobulintas informacijos saugos audito metodas, paremtas „Agile“ DSDM „Atern“ metodu. Siūlomas metodas išbandytas praktiškai, o gauti efektyvumo rezultatai palyginami su tradicinio metodo efektyvumo kriterijais. Atliktas eksperimentas patvirtino, kad siūlomas informacijos saugos audito metodas vertinant skiriamų išteklių prasme yra efektyvesnis nei tradicinis metodas. Darbą sudaro 6 dalys: įvadas, informacijos saugos audito ir „Agile“ metodų analizė, siūlomo informacijos saugos audito, paremto „Agile“ principais, metodo aprašymas, siūlomo metodo išbandymas, išvados ir literatūros sąrašas. Darbo apimtis – 55 p. teksto be priedų, 12 pav., 10 lent., 42 bibliografiniai šaltiniai.The thesis analyzes the information security audit process and the possibility to improve it using Agile approach. The theoretical part of the work presents the traditional information security method, align it with the Waterfall approach. The analysis of traditional method revealed the limitations of this approach, such as detailed audit planning needed at the beginning of the audit, any change of the audit plan is complicated. Attempts to optimize this method only partially solves these problems. There was no offers to transform the method before. Agile method analysis has confirmed assumptions that this method can be used in information security audit process in order to make it more efficient. In the practical part of this work is offered improved information security audit method based on Agile DSDM Atern method. The proposed method was tested in practice, and the performance results were compared with the traditional method performance results. An experiment has confirmed that the proposed method of information security audit is more effective of the resources allocated than the traditional method. Structure: introduction, analysis of informacion security audit and Agile methods, proposing information security audit method, based on Agile principles, testing of propsed method, conclusions references. Thesis consist of: 55 p. text without appendixes, 12 pictures, 10 tables, 42 bibliographical entries
Analysis of poverty indicators
No full textBaigiamajame magistro darbe supažindinama su pagrindiniais skurdo rodikliais: skurdo rizikos riba, skurdo rizikos lygiu, skurdo rizikos gyliu ir kvintilinių sumų santykiu. Vertinamos šių rodiklių dispersijos veidrodinės savirankos metodu. Rodiklių vertinimui naudojami 2012 metų Europos socialinio tyrimo duomenys. Rodikliai vertinami Lietuvos, Estijos ir Švedijos populiacijoms. Pateikiama informacija apie duomenų pertvarkymą bei papildomų duomenų kūrimą, naudojami atitinkami imties planai. Įvertinti rodikliai lyginami su Eurostato internetiniame puslapyje skelbiamais rezultatais. Pateikiamos baigiamojo darbo išvados. Darbą sudaro 2 dalys: įvadas, skurdo rodiklių apibrėžimai ir jų vertinimo metodai, Estijos, Lietuvos, Švedijos skurdo rodiklių vertinimas ir jų palyginimas, išvados, literatūros sąrašas, priedas – programos kodas. Darbo apimtis – 34 p. teksto be priedų, 2 iliustr., 15 lent., 9 bibliografiniai šaltiniai. Atskirai pridedami darbo priedai.Estimation of the main poverty indicators such as at-risks-of-poverty rate, at-risks-of-poverty threshold, at-risks-of-poverty gap and quantile share ratio is presented in the master thesis. The bootstrap method is applied for estimation of variance for estimators. European Social Survey data of 2012 is used in the thesis. Indicators are estimated for populations of Lithuania, Estonia and Sweden. The estimates of indicators are compared with the results published by Eurostat. The final conclusions are presented. Structure: introduction, definitions and estimators of poverty indicators, poverty indicators estimates for populations of Lithuania, Estonia and Sweden populations, conclusions, references. Thesis consists of: 34 p. text without appendixes, 2 pictures, 15 tables, 9 bibliographical entries. Appendix is included