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Biblioteka informuoja, 2024 Nr. 33 (677)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.33 (677)202
Biblioteka informuoja, 2024 Nr. 7 (651)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.7 (651)202
Evaluation of the organization’s performance towards green direction
No full textDisertacijoje nagrinėjamas organizacijų veiklos vykdymo žaliąja kryptimi aktualumas šiuolaikinės visuomenės žaliojo augimo ir darnaus vystymosi siekių kontekste bei veiklos vykdymo žaliąja kryptimi vertinimo organizaciniu lygmeniu problematika. Tyrimų objektas – organizacijos veiklos vykdymo žaliąja kryptimi vertinimas. Darbo tikslas – parengti teoriškai pagrįstą ir empiriškai patikrintą instrumentą, kuris leistų organizacijoms į(si)vertinti veiklos vykdymo žaliąja kryptimi situaciją bei priimti valdymo sprendimus, didinančius žaliųjų praktikų taikymą, tokiu būdu prisidedant prie žaliojo augimo bei darnaus vystymosi tikslų įgyvendinimo.
Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašai ir aštuoni priedai.
Pirmajame disertacijos skyriuje pagrįstos organizacijos veiklos vykdymo žaliąja kryptimi vertinimo instrumento kūrimo prielaidos. Antrajame disertacijos skyriuje išanalizuota esama organizacijos veiklos vertinimo žaliąja kryptimi metodinė bazė ir išgrynintas pjūvis organizacijos veiklos vertinimo žaliąja kryptimi instrumentui kurti, identifikuotos vertinamos kuria-mo instrumento dedamosios, sukurta vertinimo rezultatų matavimo skalė ir pasiūlytas teorinis organizacijos veiklos vertinimo žaliąja kryptimi instrumentas – organizacijos išteklių vertinimo žaliąja kryptimi įrankis. Trečiajame disertacijos skyriuje pateikti organizacijos išteklių vertinimo žaliąja kryptimi įrankio empirinio tyrimo rezultatai ir jų apibendrinimas. Apibendrinus empirinio tyrimo rezultatus bei atsižvelgus į ekspertų pastebėtus įrankio privalumus, trūkumus ir tobulinimo rekomendacijas, pateikta patikslinta galutinė įrankio versija bei papildyta jo praktinio taikymo metodika. Taip pat empirinio tyrimo metu nustačius rekomendacijų organizacijoms poreikį, parengtas rekomendacinio pobūdžio žaliųjų praktikų taikymo organizacijos išteklių valdyme gairių rinkinys. Skyriaus pabaigoje aptartos organizacijos išteklių vertinimo žaliąja kryptimi įrankio praktinio taikymo organizacijose perspektyvos ir galimos tolesnių tyrimų kryptys.
Disertacijos tema paskelbtos 7 publikacijos, trys iš jų – recenzuojamuose mokslo žurnaluose, įtrauktuose į duomenų bazes (viena – į Clasivate Analytics Web of Science, dvi – į Scopus). Disertacijos tema perskaityti 7 pranešimai Lietuvoje ir kitose šalyse vykusiose konferencijose.The dissertation investigates the relevance of the organization’s performance towards green direction in the context of the goals of green growth and sustainable development of modern society and examines the problematic aspects of evaluating an organization’s performance towards green direction at the organizational level. The object of research is the evaluation of the organization’s performance towards green direction. The dissertation aims to develop a theoretically based and empirically verified instrument that would allow organizations to evaluate the current situation of their performance towards green direction and to make management decisions that increase the application of green practices, thereby contributing to the implementation of green growth and sustainable development goals.
The dissertation consists of three parts, including an Introduction, three chapters, Conclusions, References, and eight Annexes.
The first chapter of the dissertation justifies the assumptions for the development of the instrument for the evaluation of the organization’s performance towards the green direction. The second chapter analyzes the existing methodical base for the evaluation of the organization’s performance towards green direction, identifies the perspective for the development of the instrument for its evaluation, proposes components of the instrument, creates a scale for measuring the evaluation results, and proposes a tool for the assessment of an organization’s resources towards green direction as a theoretical instrument for the evaluation of the organization’s performance towards green direction. The third chapter of the dissertation presents the results of the empirical research of the proposed tool. After summarizing the results of the empirical research and considering the advantages, disadvantages, and improvement recommendations of the tool observed by the experts, a revised final version of the tool is presented, and the methodology of its practical application is supplemented. In addition, the identified need for organizations to have recommendations resulted in a proposed set of guidelines for the application of green practices in the management of the resources of an organization. The chapter closes with a discussion of the perspectives on the practical application of the tool in organizations and possible directions for further research.
Seven articles on the dissertation’s topic were published, and three of them were published in peer-reviewed scientific journals included in databases (one in Clasivate Analytics Web of Science, and two in Scopus). The research results were presented at seven scientific conferences in Lithuania and abroad.Taip / Ye
Studies of sound absorption and sound transmission loss of hemp shives
No full textAtsižvelgiant į globalias tvarumo tendencijas, sintetinės garsą slopinančios medžiagos vis dažniau keičiamos natūralios kilmės medžiagomis. Viena iš tokių medžiagų – pluoštinės kanapės. Nors pasaulyje kanapių pluoštas ir spaliai yra pakankamai gerai ištirti, mokslininkai akcentuoja tyrimų poreikį atskirai kiekvienam regionui, kur auginamos pluoštinės kanapės, nes jų savybės labai skiriasi dėl aplinkos sąlygų įtakos įvairiose jų auginimo vietovėse. Šio tyrimo tikslas – ištirti Lietuvoje užaugintų pluoštinių kanapių spalių, spalių ir pluošto mišinio bei spalių blokelio garso sugerties ir garso izoliavimo savybes ir jų priklausomybę nuo tiriamų bandinių storio ir tankio. Eksperimentiniai tyrimai atliekami vadovaujantis standartiniais metodais ISO 10534-2 ir ASTM E2611-17. Nustatyta, kad didesnio storio kanapių spalių ir kanapių spalių su pluoštu bandiniai geriau sugeria garsą vidutiniuose ir žemuosiuose dažniuose. 150 kg/m3 tankio bandiniai daugeliu atvejų geriau sugeria garsą visame dažnių diapazone, lyginant su to paties storio 100 kg/m3 tankio bandiniais. Sumaišius kanapių spalius su dekortikuotu kanapių pluoštu, pagerėjo garso sugertis visoje dažnių juostoje.Taking into account global sustainability trends, synthetic sound-absorbing materials are increasingly being replaced by natural materials. One such material is hemp fiber. Although hemp fibers and shives are quite well researched worldwide, scientists emphasize the need for research tailored to each region where hemp fibers are grown, as their properties vary greatly due to environmental conditions in different growing locations. The aim of this study is to investigate the sound absorption and sound insulation properties of hemp shives, shive and fiber mixtures, and shive blocks grown in Lithuania, and their dependence on the thickness and density of the samples tested. Experimental studies are conducted following standard methods ISO 10534-2 and ASTM E2611-17. It has been found that samples of thicker hemp shives and hemp shives with fiber better absorb sound at medium and low frequencies. Samples with a density of 150 kg/m3 generally absorb sound better across the entire frequency range compared to samples of the same thickness but with a density of 100 kg/m3. Mixing hemp shives with decorticated hemp fiber improved sound absorption across the entire frequency band.Taip / Ye
Person Detection in Thermal Images: A Comparative Analysis of YOLOv8 and YOLOv9 Models
No full textPerson detection in thermal imagery is crucial for surveillance and monitoring applications. We assess the performance of YOLOv8 and YOLOv9 models using a new thermal image dataset. Our study reveals that both models achieve high precision, with YOLOv8 showing a superior training time and inference speed compared to YOLOv9. Specifically, YOLOv8 models achieve precision rates of 89% to 90 %, outperforming YOLOv9 with precision ranging from 87% to 88%. Moreover, YOLOv8 models demonstrate faster training times and lower inference processing times, making them more suitable for real-time applications. Despite challenges such as false positives and false negatives, our findings provide valuable insights into improving the accuracy and efficiency of thermal-based person detection, thereby enhancing surveillance and monitoring systems.Taip / Ye
Enhancing regulatory clarity through insights on retroactive and retrospective applications of the unclaimed financial asset act in Kenya
No full textThis study delves into Kenya’s Unclaimed Financial Assets Act, examining its retrospective application in finance. While grounded in English Common Law, the Act faces hurdles in reporting and compliance due to its retroactive nature. Through analysis, it uncovers limitations and stresses stakeholder involvement, regulatory clarity, interpretation flexibility, and education for compliance. Its insights benefit policymakers and stakeholders grappling with unclaimed financial assets in Kenya’s regulatory evolution.Taip / Yes
Understanding sustainability transformation at corporations: terms and categorization
No full textSustainable business management transformation is associated with one of the biggest potentials for economic benefit and an increasing number of companies are joining the transitioning pathway. There is a research gap in both the definitions of sustainability transformation and the framework on how businesses manage skills, processes, and organizational activities to facilitate it. The focus of this research is to understand the scope of sustainability transformation in corporations, namely, how the concept of sustainability transformation has been defined and researched in the context of corporations due to their scale, impact, and exposure. Corporations are expected to lead toward true ecosystem value creation and as such, are of special interest and weight within the private sector. The research concludes that interpretations of sustainability transformation range from incremental to systemic changes, underlining the complexity of evaluating and implementing sustainability in a corporate environment.Taip / Yes
Exploring the relationship between government DEBT and real GDP: a panel ARDL analysis
No full textThis study explores the impact of government debt on real GDP in 37 high-income economies from 1990 to 2019, using quarterly data and panel ARDL models with the PMG estimator to distinguish between short-run and long-run effects. Despite identifying a non-linear relationship between government debt and real GDP, suggesting a long-term debt threshold of 95% to 110%, robustness checks using the Common Correlated Effects estimator to adjust for cross-sectional dependence find no significant long-term impact of government debt on real GDP. This conclusion calls into question the existence of a universal debt threshold affecting economic growth in high-income economies and contributes to the debate on the optimal level of government debt and its economic effects.Taip / Yes
Relationship between the dynamics of refugees from Ukraine and the volatility of tourism stocks: a time-frequency analysis
No full textThe Russia-Ukraine war has determined the reconfiguration of the tourism industry at the global level. This study explores the link between refugees from Ukraine and tourism stocks listed on the Bucharest Stock Exchange. The analysed period was between 01.01.2022 and 31.12.2022 to capture the extent of the studied phenomenon. The time series were processed by wavelet analysis. The main results are: i) there is a link between the dynamics of refugees in Ukraine and the volatility of tourism stocks; ii) volatility was significant in the first weeks after the start of the conflict in most of the analysed companies; iii) the highest volatility was recorded in companies located near the Ukraine border; iv) in 2023, the volatility generated by refugees from Ukraine is insignificant.Taip / Yes