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The vertical and horizontal dimensions in the social construction of leadership: A case study on the social media followers of the Croatian politicians Zoran Milanović and Miro Bulj /
No full textThis research examines the social construction of political leadership by social media followers of two Croatian politicians, president Zoran Milanović, and the mayor of Sinj, Miro Bulj, within the context of celebrity politics and populism. Through the interaction between theory and analysis, we integrate elements that construct leadership into what we distinguish as vertical (extraordinary) and horizontal (ordinary) dimensions, adding populism as an element of both dimensions. This analysis is grounded in the qualitative content analysis of 20 interviews with the two politicians’ Facebook followers, empirically showing that neither one of the elements is dominating the construction of leadership, putting the focus on the importance of the balance between the dimensions of verticality and horizontality, with modesty allowing for the mediation between the extraordinary and the ordinary. Equally important is the followers position that a perfect balance between verticality and horizontality (and a perfect leader) cannot be achieved. In short, leadership is shown to be paradoxical but not contradictory, as it is an always imperfect reconciliation of the horizontal and vertical dimensions.iss. 6vol. 1
Foam glass granule usage in tile glue mixtures that use a reduced portland cement amount
No full textIn the last few years, ceramic tiles and tiles from natural rock with higher measurements were used. A huge amount of tile glue is used for high-measurement tile gluing due to a special gluing technology, which is characterized by a thicker glue layer. Due to this, a higher and higher amount of tile glue is used up during decorating. Regular tile glue mixture uses up to about 50–60% cement (according to mixture mass). In carried-out experiments, a lower amount of cement was used in tile glue mixture production (30%). Additionally, 5%, 10%, 15%, 20% and 25% of sand was replaced with small foam glass granules. These granules are made from glass waste. By using foam glass granules, lighter tile glue mixtures were produced, while reducing the cement amount can lower energy usage and CO2 emissions into the atmosphere. The main properties of tile glue were investigated as follows: flow of mixture, density, compressive strength, bending strength, tensile-adhesive strength, slip and water absorption. The properties obtained during the research prove that newly produced tile glue mixtures fulfill all requirements given to these types of mixtures. A total of 25% of foam glass granule from filler mass can be used in tile glue production.iss. 3vol. 1
Investigation of Primary Sludge Hydrolysis Process
No full textSiekiant užkirsti kelią eutrofikacijos procesui, taikomi griežti reikalavimai biogeninėms medžiagoms valytose nuotekose. Biologiškai skaidomų organinių medžiagų trūkumas yra viena iš priežasčių, dėl kurios azoto ir fosforo junginiai iš nuotekų šalinami neefektyviai. Pirminio dumblo hidrolizės procesas yra vienas iš būdų, kurio metu galima pagaminti lengvai biologiškai skaidomų organinių medžiagų ir taip užtikrinti reikalaujamą biogeninių medžiagų pašalinimą iš nuotekų. Šio darbo tikslas laboratorinėmis sąlygomis nustatyti pirminio dumblo hidrolizės proceso dumblo išbuvimo trukmės reikšmę, kuriai esant susidaro optimalus organinių medžiagų kiekis, ir įvertinti susidariusių organinių medžiagų poveikį biogeninių medžiagų šalinimo iš nuotekų procesui. Pirminio dumblo hidrolizės tyrimams naudotas pirminis dumblas iš Vitebsko (Baltarusija) nuotekų valyklos ir Vilniaus nuotekų valyklos. Pirminio dumblo hidrolizės proceso efektyvumui nustatyti buvo analizuota pirminio dumblo išbuvimo trukmė, ChDStirp., BDS7, TGLRR susidarymas, BSM suskaidymas. Tyrimai atlikti esant 20,8 ?C vidutinei temperatūrai, 7,35 pradinei pH reikšmei. Nustatyta rekomenduojama optimali dumblo išbuvimo trukmė – 6 paros. Pagal minėtas sąlygas tyrimo Nr. 1 ir tyrimo Nr. 3 metu ChDStirp. susidarymo efektyvumas lygus 69,5 %, TGLRR susidarymo efektyvumas lygus 71,4 %. Šie rezultatai pasiekti, kai BSM suskaidymas buvo apie 5 %. Laboratoriniais pirminio dumblo hidrolizės tyrimais nustatytą optimalią ChDS reikšmę pritaikius Vitebsko miesto išorinio anglies šaltinio poreikio skaičiavimui nustatyta, kad dėl pirminio dumblo hidrolizės proceso ChDS reikšmė padidėjo 3 %: pradinė ChDS reikšmė buvo 501 mg/l, po hidrolizės proceso – 516 mg/l. Darbą sudaro šios dalys: įvadas, keturi skyriai, išvados ir siūlymai, literatūros sąrašas. Darbo apimtis – 61 p. teksto be priedų, 18 iliustr., 11 lent., 48 bibliografiniai šaltiniai.In order to prevent eutrophication process strict effluent requirements for nutrients are applied. The lack of readily biodegradable organic matter usually is a factor for non-efficient removal of nutrients form wastewater. Hydrolysis of primary sludge is one of the method to produce readily biodegradable organic matter and ensure the more efficient nutrient removal and low-cost maintenance of wastewater treatment. Therefore, the aim of this research is to determine the importance of the sludge retention time of primary sludge hydrolysis process in the laboratory conditions, which results in the optimal amount of organic matter, and allows to assess the effect of the organic matter produced on the process of biogenetic discharges from wastewater. Primary sludge from primary settlers of Vitebsk WWTP, Belarus (Investigation No. 1, Investigation No. 3) and Vilnius WWTP, Lithuania (Investigation No. 2) was used for primary sludge hydrolysis investigation. Primary sludge hydrolysis was performed to determinate the retention time, formation of SCOD, BOD, SCVFA and reduction of VSS. The results of investigations were performed in the average temperature of 20.8 ?C with initial pH value of 7.35. The recommended retention time of 6 days for primary sludge hydrolysis was determined. Under the abovementioned conditions the efficiency of SCOD formation was equal to 69.5 %, the efficiency of SCVFA formation was equal to 71,4 %. This result was achieved with 5 % of VSS reduction. By applying the optimal value of COD determined by laboratory analysis of primary sludge to the calculation of the need for the external carbon source in the Vitebsk city, it was determined that the COD value increased by 3 % due to the primary sludge hydrolysis process: initial COD value was 501 mg/l, after hydrolysis process – 516 mg/l. Work comprises the following components: introduction, 3 sections, conclusions, recommendations and references. Work is of 61 p. of test without appendixes, 18 pictures, 11 tables and 48 references
How does environmental data from ESG concept affect stock returns: Case of the European Union and US capital markets
No full textThis article examines the environmental, social, and governance (ESG) performance of firms, with a focus on the environmental pillar of the ESG concept. It is believed that the price of equities as well as sector-specific characteristics may be affected by ESG data. It also contributes to the argument that environmental performance and governance quality are related. The purpose of this paper is to statistically validate the separated environmental data from the ESG concept and investigate its impact on the equity price in the EU and the United States. Using simple linear regressions and a fixed effect panel data model, the association between environmental score and governance score, as well as equity price and environmental score, was estimated. This study examines the 500 largest US corporations comprising the S&P 500 index (S&P) and the 600 largest EU companies comprising the STOXX Europe 600 index (STOXX) (SXXP). This article analyzes ESG statistics for the period 2015–2020. The results indicate that a higher government score has a favorable effect on environmental pledges and that changes in stock price depend in part on environmental data. The novel contribution of this paper is that the results suggest a sector-specific contribution to the model, and it would be fascinating to analyze sector disparities and their ESG-related policies in greater detail.iss. 2vol.
Microwave Medical Imaging System for Brain Injury Diagnosis
No full textMikrobangų medicininio vaizdinimo sistema smegenų traumoms diagnozuoti. Magistro baigiamasis darbas elektronikos inžinerijos laipsniui. Vilniaus Gedimino technikos universitetas. Vilnius, 2019, 71 p., 47 iliustr., 7 lent., 34 bibl., 5 priedai. Darbo tikslas – sukurti sistemą, sudarytą iš aparatinės ir programinės įrangos, kuri gebėtų atvaizduoti žmogaus smegenyse esančias smegenų traumas ar netipinius pakitimus. Atlikus analogiškų sistemų analizę pasirinktas naudoti spektrinis metodas. Suprojektuotos plačiajuostės antenos ir jų aukštadažnis perjungiklis. Signalai generuoti ir priimti naudojant VNA. Jo automatizuoto valdymo kodas ir spektrinis metodas realizuotas „Matlab“ programiniame pakete. Iškeltas tikslas yra įvykdytas. Sukurta ir ištirta mikrobangų medicininio vaizdinimo sistema. Veikimas įrodytas naudojant dirbtinius galvos maketus.Microwave Medical Imaging System for Brain Injury Diagnosis. Master‘s thesis in electronic engineering. Vilnius Gediminas Technical University, 2019, 71 p., 47 pictures, 7 tables, 34 bibliographical entries, 5 appendixes. The study focuses on the development of a microwave imaging system to create images of the human brain interior for medical application using frequency-based imaging algorithm. Compact RF switching system is proposed. An array of twelve wide band antennas were connected to the system and its overall performance was evaluated. VNA is used to generate and acquire microwave signals. The code was written in MATLAB. The performance of the system are tested via experiments on phantoms. The results of the investigation prove that the system which has been developed meets all the requirements of the task
Investigation of weldability of structural S355 and duplex 1.4462 steels
No full textBaigiamajame magistro darbe nagrinėjama konstrukcinio mažaanglio plieno S355 ir duplex plieno 1.4462 virintinės jungties suvirinamumas, tyrimui naudojant 3 skirtingas pridėtines medžiagas ir skirtingus plokštelių briaunų paruošimus. Tyrimą atliekant ardomosios ir neardomosios kontrolės metodais. Buvo išmatuotos deformacijos po suvirinimo, atlikta apžiūrimoji kontrolė, atlikta skvarbiųjų dažalų kontrolė, makrostruktūros tyrimas, kietumo matavimas. Gauti tyrimų rezultatai, nubraižyti priklausomybių grafikai ir pateiktos išvados. Darbą sudaro: įvadas, literatūros apžvalga, tyrimo metodai, rezultatų analizė, tyrimo rezultatai, išvados, literatūros sąrašas.The final master's thesis examines the weldability of the welded joint of structural low-carbon steel S355 and duplex steel 1.4462, using 3 different additive materials and different plate edge preparations. Investigating by destructive and non-destructive control methods. Deformations after welding were measured, visual control was performed, control of penetrating dyes was performed, macrostructure study, hardness measurement was performed. Research results were obtained, dependency graphs were drawn, and conclusions were presented. The work consists of introduction, literature review, research methods, analysis of results, research results, conclusions, bibliography
Diagnostics of pre-fault conditions using the impact of electrolytic capacitor aging on power supply dynamics
No full textThe modern power electronics is indistinctive to questions on a reliability. The electrolytic capacitors despites their excessive properties in terms of affordability, power density to volume and weight, remains an element that can cause device fail. The paper is dedicated to a solution to diagnostics, monitoring and prediction of remain lifetime of electrolytic capacitors. The main idea is that ESR (Equivalent Series Resistance) of capacitor grows while capacitor is getting to the end of the lifespan. ESR in combination with the capacitance is forming a Left Half-Plane zero and thus change in listed parameters is affecting overall transfer function. This paper uses buck converter as an example. The data for capacitors models is obtained from real accelerated aging experimental results. Modelling at different lifespan periods shows change in response to disturbance. The paper proposes to use band-pass filter to get signal that is easy to process further. The paper also has a little discussion on potential uses of the signal and their advantages and disadvantages
Features selection for classification of speech emotions
No full textMagistro baigiamasis darbas informatikos inžinerijos laipsniui. Vilniaus Gedimino technikos universitetas. Vilnius, 2017, 70 p., 12 iliustr., 11 lent., 39 bibl., 2 priedų. Baigiamajame magistro darbe siekiama ištirti emocingos šnekos akustinių požymių atrankos metodus, pasiūlyti sprendimus požymių daugiamatiškumui sumažinti. Dėl didelio emocingos šnekos signalo charakteristikų skaičiaus emocijų klasifikavimo patikimumas būna žemas, todėl verta mažinti analizuojamų požymių rinkinį. Šiam tikslui pasiekti naudojami įvairūs požymių atrankos metodai. Baigiamajame darbe požymių atrankai pritaikyti aplanko tipo metodai. Eksperimentiškai ištirti 5 požymių rinkiniai: pilna požymių aibė ir 4 suformuoti, naudojant aplanko metodo atrankos algoritmus. Geriausiai klasifikavimo rezultatai gauti naudojant nuoseklios paieškos algoritmus – didžiausias klasifikavimo tikslumas pasiektas naudojant mažiausius požymių rinkinius.Master's thesis informatics engineering degree. Vilnius Gediminas Technical University. Vilnius, 2017, 70 p., 12 pic., 11 tables, 39 references, 2 additives The master thesis aims are to explore the application of feature selection techniques for emotional speech classification and to offer solutions for feature dimensionality reduction. High dimensionality of the features sets can result in low accuracy classification of the speech emotions, therefore the feature sets should be reduced. Various feature selection techniques are used for this purpose. The feature wrapping selection techniques were analyzed in this work. An experimental study of 5 different feature sets were performed: a full feature set and 4 wrapping selection based sets were employed for speech emotion classification task. The best results were obtained by using sequential selection algorithms: the highest classification accuracy was achieved by using lowest order feature set
Research of Learning Efficiency for Children with Autism Spectrum Disorders in different Education Forms
No full textBaigiamajame magistro darbe nagrinėjamos autizmo spektro sutrikimų turinčių vaikų mokymosi problemos. Sudaryta metodika vaikų mokymosi efektyvumui tirti. Pagal iškeltas hipotezes prieš tyrimą, pateikiami rezultatai bei sudarytos rekomendacijos vaiko mokymosi efektyvumui, naudojant FM bevielę ryšio sistemą, užtikrinti. Darbą sudaro 6 dalys: įvadas, teorinė mokslo darbų analizė, tyrimo metodikos sudarymas, tyrimo rezultatai ir rekomendacijų pateikimas, išvados, literatūros sąrašas. Darbo apimtis – 51 p. teksto be priedų, 29 iliustr., 3 lent., 30 literatūros šaltinių.A final thesis presents learning problems of children with autism spectrum disorders. A methodology was developed to research the effectiveness of children's learning. According to the hypothesis described before the study, the results and recommendations for the effectiveness of the child's learning using FM wireless communication system are provided. Structure: introduction, definitions, theoretical analysis of scientific works, creation of research methodology, research results and presentation of recommendations, conclusions, references. Thesis consist of: 51 p. text without appendixes, 29 pictures, 3 tables, 30 bibliographical entries
The corporate social responsibility disclosure of the Romanian banking system during the COVID-19 pandemic
No full textThe present paper explores the CSR informational asymmetry of the Romanian banking sector during the COVID-19 pandemic, using multiple case studies. The research results outline that the CSR activity was not properly exploited by the banks during the pandemic, strengthening the increasing visibility of the economic performance as part of the corporate social responsibility approach. The research methodology was organised in a three-step process: a content analysis, computation of a CSR scorecard based on Global Reporting Initiative guidelines and testing the effect of the CSR disclosure on the banks’ resilience during pandemic. The regression analysis positively relates the CSR score to the banks’ performance, suggesting that 29.8% variation in total net assets is explained by the independent variable CSR score. The main findings of the paper are significant in the banks’ transition to digital banking, assisting decision makers from banks in implementing appropriate CSR disclosure mechanisms.Taip / YesI