Journals Published by Vilnius Tech
Not a member yet
12596 research outputs found
Sort by
Evaluation of heavy metal pollution in groundwater resources of Konaro area, Iranshahr, SE Iran: implication for ophiolitic rocks impact
Get PDFThis study, it has been attempted to investigate the heavy metals pollution in groundwater resources of Konaro area. Accordingly, eight representative groundwater samples from wells and qanat were collected in December 2017 from rural settlements commonly used for irrigation and drinking. Analysis of lead, zinc, iron, chromium, copper and nickel as heavy metals was conducted by the ICP-MS approach. The results of analyzes indicate that the concentration of heavy metals in the groundwater of the study area is lower than the permissible limit. Results of HEI, HPI, and Cd contamination indices show that 62.5% of samples in the Konaro area fall into the medium pollution group, and the rest of the samples fall into the low pollution group due to their heavy metals content. Studies show that all samples of groundwater in the Konaro area have low to moderate contamination and that the overall contamination rate is not dangerous. Correlations between heavy metals indicators demonstrate that HPI is strongly correlated with HEI and Cd also HEI with Cd. Therefore, it is evident that all of the indices are important and reliable to study the risk of heavy metals pollution in the Konaro ophiolitic area. Pollution evaluation indices and statistical analysis confirm that the low to medium level of heavy metals in Konaro groundwater samples is owing to the lack of acidity, poor agriculture and poor urbanization around the river and thus the lack of contamination of the aquifer
Sustainable recovery plan for an urban-rural community affected by the Fundão Dam disaster in Brazil
Get PDFThe rupture of Fundão Dam spilled contaminated tailings across the Doce river basin, severely damaging municipalities such as the urban Barra Longa and the rural Gesteira. The wave of tailings led to the sediment deposition in rivers margins, causing the loss of riparian forests and cropping areas. Sediment analyses confirmed the presence of toxic compounds (sodium and ether amine) and a very low fertility. In consequence, there was a sharp decline in agro-pastoral production in Gesteira, leading to land abandonment and rural exodus. In the urban area of Barra Longa, the wave of tailings damaged the urban floodplain and the square, which were rehabilitated using grey infrastructure. Alternatively, we proposed a new landscape recovery plan for both Barra Longa and Gesteira based on Nature and Community-based solutions that contemplate the inclusion of green infrastructure, the remediation of toxic compounds, the restoration of soil fertility, permeability and stabilization, riparian forest rehabilitation and the recovery of agro-pastoral productivity, ultimately aiming at reducing the flood risk and land abandonment
Study on suitability assessment method of vegetation restoration species in disturbed sites of transmission line engineering construction
Get PDFScreening species that can adapt to the disturbed habitats resulting from transmission line construction is of great practical significance for the ecological restoration of primary vegetation degradation caused by such construction. Therefore, a suitability evaluation method for vegetation restoration species in disturbed areas of transmission line engineering construction is studied to improve the ecological restoration. Based on the principles of stability and durability, adapting to local conditions and trees, and comprehensive and dominant screening, an index system for evaluating the adaptability of vegetation restoration species is established. Determine the subjective weight of evaluation index by G1 method and G2 method. The objective weight of evaluation index is determined by improving entropy weight method and deviation method. Through the optimal combination weighting method, the final evaluation index weight is obtained by combining subjective weight and objective weight. Using cloud model combined with index weight to calculate the certainty of each index. According to the principle of maximum certainty, the evaluation grade corresponding to the maximum certainty is selected as the final suitability evaluation result. The experiments have demonstrated that the suitability evaluation index system of this method exhibits high reliability, and it can effectively determine the weights of the suitability evaluation indices and complete the suitability assessment for vegetation restoration species. Among these species, Elymus chinensis, Panicum miliaceum, Brassica napus, arugula, and rye exhibit the most promising ecological restoration effects
Assessment of sustainable road transport in Lithuania
Get PDFRoad transport plays an important role in our lives. In Lithuania, passenger road transport accounted for more than 47% in 2022, and freight road transport more than 87% of the transport sector. Up to 15% of the Lithuanian population works in this sector (in 2020). However, road transport is one of the most polluting. In 2021, it represented 72% of all greenhouse gas emissions from EU domestic and international transport. In order to solve this problem, the EU plans to ban the sale of vehicles with internal combustion engines by 2035. So, the question arises: what challenges will the country’s transport sector face, what measures/innovations will it adopt to reduce greenhouse gas emissions? To answer this question, the article analyzes the road transport sector and identifies measures to improve the sustainability of the sector, increase turnover, and observes the impact of those measures on road transport turnover. The purpose of the research is to determine the factors affecting the circulation of passengers and cargo by road transport based on scientific literature and to empirically verify their influence on the sustainability of the country. In order to achieve the set goal, the analysis is carried out in two blocks: the study of the turnover of road transport cargo and the study of the turnover of road transport passengers. The following methods are used for the research: correlation regression analysis, forecasting. The research results are important for policy makers and practitioners in the context of sustainable transport development
Emergent approach to business resilience: a study of Ukrainian enterprises
Get PDFThis study aims to profile the emergent behavioral responses of small and medium-sized enterprises (SMEs) in Ukraine to radical market changes and identify the cause-effect relationships that ensure their resilience through an emergent approach to strategic management. The article analyzes the results of a survey of 500 enterprises within the project “Advisory Support to SMEs in Ukraine Amid the Military Crisis”, implemented by CMC-Ukraine with support from Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ). Data were analyzed using MS Excel and RStudio. The study found that strategic decision-making profiles varied by sector. Grouping responses by functional areas (marketing, operations, finance, HR, digitalization) helped identify emergent strategy frameworks for different company clusters. These best practices were applied in the project “Access to Finance and Support for the Resilience of SMEs in Ukraine”, funded by Deutsche Sparkassenstiftung für Internationale Kooperation, which ran from February to August 2023
Exploring future scenarios for Latvia’s regional business incubators
Get PDFThe research demonstrates that since 2007, the business incubator programs administered by the Investment and Development Agency of Latvia (LIAA) have significantly boosted regional entrepreneurship in Latvia. These programs provide essential support to young entrepreneurs, promote employment, stimulate entrepreneurship, and enhance the quality of life in the regions. Additionally, they increase export capacity and tax revenues. In this period, business incubators have been operated by the state, universities and private companies. The research analyzed future scenarios for the further development of regional business incubators in Latvia. Using the Analytic Hierarchy Process (AHP) and expert assessments, the study considered Latvia’s economic and social goals and strategic directions for regional development, underscoring the critical role of business incubators in promoting regional entrepreneurship and societal well-being. The research explored the possibility of transferring the administration of regional incubators to private companies, universities, or municipalities, which could impact regional economic development. A detailed assessment of previous LIAA programs concluded that various organizations, including private companies and universities, could effectively manage regional business incubators, fostering innovation and new product creation
Convergence analysis of a class of iterative methods: a unified approach
Get PDFIn this paper, we study the convergence of a class of iterative methods for solving the system of nonlinear Banach space valued equations. We provide a unified local and semi-local convergence analysis for these methods. The convergence order of these methods are obtained using the conditions on the derivatives of the involved operator up to order 2 only. Further, we provide the number of iterations required to obtain the given accuracy of the solution. Various numerical examples including integral equations and Caputo fractional differential equations are considered to show the performance of our methods
Co-governance of online car-hailing operation based on passenger feedback
Get PDFThe illegal operation of online car drivers is a recurring issue that has garnered significant societal attention. The literature has investigated this problem primarily from the perspectives of the government, platforms, and drivers, while the mechanisms for co-governance among different stakeholders in addressing illegal online car-hailing operations have received limited focus. Additionally, the role of passengers in the online car-hailing process has not been sufficiently explored, leading to a lack of systematic research conclusions and inherent limitations. To analyse the evolutionary equilibrium strategies of participants under various scenarios and their influencing factors, a tripartite evolutionary game model involving passengers, drivers, and online car-hailing platforms was constructed. The decision-making behaviours of these stakeholders were examined through numerical simulation. The results indicate that by strengthening investigations and addressing illegal behaviours, online car-hailing platforms can significantly reduce the likelihood of drivers′ illegal operations. Furthermore, increasing the amount of guarantee deposits can increase drivers′ respect for regulations. Additionally, improving passenger satisfaction can be achieved by increasing compensation for participation in co-governance and increasing promotional rewards from platforms, thereby enhancing service quality. Strengthened supervision strategies not only boost platforms′ social reputation and management efficiency but also create positive incentives for strict supervision through penalty income. This study provides a theoretical foundation for optimizing the supervision of the online car-hailing industry, emphasizing the critical roles of strict supervision, positive incentives, and public participation in elevating service standards. The findings enrich the theoretical understanding of online car-hailing market supervision and offer innovative co-governance strategies aimed at fostering the healthy development of the online car-hailing market
Blockchain-based secure communication for UAV networks: a decentralized approach to GNSS spoofing detection
Get PDFEnsuring secure communication in Unmanned Aerial Vehicle (UAV) networks is a critical challenge due to vulnerabilities such as GNSS (Global Navigation Satellite System) spoofing, jamming, and unauthorized data manipulation. This research investigates the feasibility of blockchain technology as a decentralized and immutable framework for enhancing UAV communication security. A blockchain-based GNSS spoofing detection system is designed, implemented, and validated within a simulated environment integrating AirSim, Ethereum blockchain (Ganache), smart contract (Solidity), and Python-based UAV simulations. The proposed system employs a consensus mechanism among UAVs to detect anomalous GNSS data and mitigate spoofing attacks in real-time. Performance evaluation metrics – transaction latency, blockchain throughput, gas consumption, detection accuracy, storage usage, and energy consumption – demonstrate the system’s capability to securely validate UAV location data. Findings indicate that blockchain ensures data integrity and resilience against cyber threats, though challenges related to transaction latency, scalability and computational overhead persist. The study contributes to the field of aerospace cybersecurity and IoT-based UAV networks by proposing an innovative approach to autonomous, trustless UAV coordination. Future work will focus on optimizing the consensus mechanism and reducing blockchain resource consumption to enhance real-world applicability
The role of outdoor advertising in consumer behaviour in implementing the goals of sustainable development: a case study of Lithuania
Get PDFThe article discusses the possibilities of managing consumer behavior in the context of implementing the goals of sustainable development formation through outdoor advertising and the assessment of the impact of outdoor advertising on consumer behaviour formation. Research objective – to determine the impact of outdoor advertising in consumer behaviour in implementing the goals of sustainable development. The research methods employed include descriptive analysis, quantitative analysis, and statistical techniques. The research was conducted from September 10, 2024, to September 24, 2024, based on a Lithuanian case study (N = 396). When applying a quantitative research strategy the obtained highest average estimates show that illuminated signs, advertising on outdoor video screens and large format posters in advertisements spread the message and have a great impact on consumer behaviour when implementing the goals of sustainable development. It was also found out that according to the majority of participants, the images in advertising (pictures, paintings, etc.), advertising design and outdoor advertising originality, as well as advertising content and its informative nature are the factors shaping consumer behaviour when implementing the goals of sustainable development. The use of a convenience sample, coupled with an imbalance in terms of gender and age distribution, limited the generalizability of the conclusions. There- fore, the spheres of further researches could be expanded with more representative samples and including the elements of qualitative method into the survey (e.g., open questions, group discussion (in Focus group) etc.), regression modelling and factor analysis would provide more insights and supplement quantitative conclusions. The research results provided valuable in- sights about the role of different types of outdoor advertising and its impact on consumers of different ages when implementing the goals of sustainable development and on the basis of the Lithuanian case could be easily extrapolated to other contexts while expanding the spheres of further researches, both at the national level and with cross-border samples