VGTU Journals (Vilnius Gediminas Technical University - Vilnius Tech)
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A partially derivative-free cyclic block coordinate descent method for nonseparable composite optimization
No full textIn this paper, we address a composite optimization problem in which the objective function consists of two terms: the first presents a function with a gradient that satisfies a Lipschitz–Hölder composition, while the second one is a convex function. Under general settings, we propose and analyze a new coordinate descent method that can operate without the use of derivatives. The algorithm is an adaptation of the coordinate proximal gradient method, specifically designed to consider the composite form of the objective function. We perform a complete worst-case complexity analysis, assuming that the coordinates (or blocks of coordinates) are selected in a cyclic manner. In addition, we present academic numerical examples that illustrate the efficiency of our algorithm in practical problems
Blockchain-based secure communication for UAV networks: a decentralized approach to GNSS spoofing detection
No full textEnsuring 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
No full textThe 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
The role of creative leadership in change management
No full textThe problem that exists today is that it is extremely difficult to assess the influence of a leader on the change management system, since a significant number of his individual character traits or abilities are unknown, which contributes to this. It is important to establish which factors of creativity are more important than others. The key idea of the article is to demonstrate a methodical approach, how to evaluate and select the most effective qualities of creativity in a leader in order to increase the effectiveness of the change management system. The purpose of the article is to determine the level of importance of the factors of the leader’s creativity that influence change management in the organization. The object of the study is the level and structure of the leader’s creativity in the organization. The research methodology includes the method of analytic hierarchy process developed by Thomas L. Saaty, the method of expert review, which was strengthened by the Delphi method. As a result of the empirical analysis involving 40 experts from Ukraine and Poland, four key factors of leadership creativity were identified and ranked by influence: 1) openness to new ideas, 2) risk-taking ability, 3) flexibility of thinking, and 4) social interaction skills. Risk-taking ability emerged as the most influential factor in effective change management. After that, we presented the key directions of how they can be developed. These findings provide actionable recommendations for enhancing leader creativity in practical organizational settings. Rather than offering general advice for similar research, future research should test the applicability of this factor structure across different sectors, organizational sizes, and cultural contexts to validate and refine the proposed model
The influence of the human factor in decision-making in cyber security exercises
No full textCybersecurity is an interdisciplinary field that encompasses aspects of information technology, forensics, incident management, and the human factor. In cyber security, decision-making is influenced by the specialist’s technical knowledge, competencies, and professional experience. However, decisions made in extreme and complex situations are influenced by emotions, motivation, social skills, and cognitive abilities. Therefore, this paper investigated the human factor influencing decision-making of participants in cyber security exercises, and proposed a multidimensional decision-making framework. A study conducted by analyzing the data of the cyber security exercise “Amber Mist” showed that an integrated assessment of technical competencies and the human factor allows for a more accurate determination of the decision-making of a cyber security specialist and its prediction. It was determined that when analyzing decision-making in cyber security exercises, it is necessary to take the human factor into account. The results of the study can be used to improve methodologies and programs for training cyber security specialists.
Article in Lithuanian.
Žmogiškojo faktoriaus įtaka priimant sprendimus kibernetinės saugos pratybose
Santrauka
Kibernetinė sauga – tai tarpdisciplininė sritis, apimanti informacinių technologijų, kriminalistikos, incidentų valdymo aspektus bei žmogiškąjį faktorių. Kibernetinėje saugoje sprendimų priėmimą veikia specialisto techninės žinios, kompetencijos, profesinės veiklos patirtis. Tačiau ekstremaliose bei sudėtingose situacijose priimamus sprendimus veikia emocijos, motyvacija, socialiniai įgūdžiai, kognityviniai gebėjimai. Todėl šiame darbe buvo tiriamas žmogiškasis faktorius, darantis įtaką kibernetinės saugos pratybų dalyvių sprendimų priėmimui, ir pasiūlytas daugiamatis sprendimo priėmimo karkasas. Atliktas tyrimas analizuojant kibernetinių saugos pratybų „Gintarinė migla“ duomenis parodė, jog integruotas techninių kompetencijų ir žmogiškojo faktoriaus vertinimas leidžia tiksliau nustatyti kibernetinio saugumo specialisto sprendimų priėmimą ir jį prognozuoti. Nustatyta, kad analizuojant sprendimų priėmimą kibernetinės saugos pratybose būtina atsižvelgti į žmogiškąjį faktorių. Tyrimo rezultatai gali būti naudojami tobulinant kibernetinės saugos specialistų rengimo metodologijas ir programas.
Reikšminiai žodžiai: kibernetinės saugos pratybos, žmogiškasis faktorius, sprendimų priėmimas
The antecedents and consequences of sustainable involvement towards fair trade products: moderating effect of perceived consumer effectiveness
No full textThis research focuses on the role of personal values and consumer social responsibility in shaping enduring involvement and purchase intention of fair trade products, taking into account the moderating effect of perceived consumer effectiveness. This study aims to examine how these psychological and behavioral factors interact to influence consumer decisions regarding fair trade, and to identify under which conditions involvement translates into actual purchase intention. A study was conducted with 593 Tunisian consumers. The results of this study highlight the complexity of the relationship between enduring involvement and purchase behavior, revealing the influence of factors such as personal values and perceived consumer effectiveness. The study also shows that altruistic values are crucial for enduring involvement but are not sufficient to trigger purchase behavior. Furthermore, stimulation, as an individualistic value, positively impacts purchase intention. It was also found that fair trade consumers prioritize international solidarity over the geographical origin of the products. This research contributes, among other things, to addressing the gap in research concerning fair trade
Specific features of social development of territorial communities in Ukraine under martial law
No full textThe article presents the results from a study on the social development of specific communities in the Dnipro, Mykolaiv, Sumy, and Chernihiv regions of Ukraine under martial law. The purpose of the article is to present the results from an analysis of the current state of social protection for residents in territorial communities across the Dnipro, Mykolaiv, Sumy, and Chernihiv regions. The object of the article is the system of providing social services to citizens by municipal social institutions at the local level. The main provisions of the article are based on a survey of more than two hundred experienced employees of social institutions and facilities. It is shown that despite the military operations, local self-government bodies manage to fulfil the social obligations that the state has to its citizens. The article describes the main problems in the implementation of social policy at the local level: the devastating impact of war, professional burnout of specialists due to staff shortages and an increase in the volume of responsibilities, and an increase in the number of those who can apply for social assistance. It is proved that in the near future, the problems of protecting orphans, families in difficult life circumstances, and military personnel who will be dismissed from the Defence Forces of Ukraine will become more acute
Twice clustering based hybrid model for short-term passenger flow forecasting
No full textShort-term metro passenger flow prediction plays a great role in traffic planning and management, and it is an important prerequisite for achieving intelligent transportation. So, a novel hybrid Support Vector Regression (SVR) model based on Twice Clustering (TC) is proposed for short-term metro passenger flow prediction. The training sets and test sets are generated by TC with respect to values of passenger flow in different time periods to improve the prediction accuracy. Furthermore, each obtained cluster is decomposed by using the Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) algorithm and the Ensemble Empirical Mode Decomposition (EEMD) algorithm, respectively. The volatility of each component obtained after decomposition is further reduced. Then, the SVR model optimized by the Grey Wolf Optimization (GWO) algorithm is used to predict the decomposed components. Moreover, forecast based on one-month data from Xi’an Metro Line 2 Library Station (China). By comparing the prediction results of the TC condition, the Once Clustering (OC) condition and the non-clustering condition, it shows that the TC approach can adequately model the volatility and effectively improve the prediction accuracy. At the same time, experimental results show that the novel hybrid TC–CEEMDAN–GWO–SVR model has superior performance than Genetic Algorithm (GA) optimized SVR (SVR–GA) model and hybrid Back Propagation Neural Network (BPNN) model
Supporting the circular economy transition using the emergent role of the Internet of Things
No full textSupporting the circular economy transition using the emergent role of the Internet of Things. Technological and Economic Development of Economy, 30(2), pp. 338-343
Performance evaluation of sustainable energy alternatives to obtain efficient hybrid energy investments
No full textThis study evaluates the synergy of coalition for hybrid renewable energy (RWB) system alternatives. In this context, the alternative sources of hybrid RWB system are examined to illustrate the impact-relation directions among them with multi SWARA based on q-ROFs and golden cut. Next, the performances of renewable alternatives are measured in terms of the synergy of coalition with game theory and Shapley value. It is concluded that solar energy is the most suitable RWB alternative for synergy to increase efficiency in investments. However, biomass does not have a significant influence on providing synergy in energy investments. Therefore, solar energy should be prioritized for hybrid energy investments. Especially with the effect of technological developments, the efficiency of solar energy investments increases significantly. Thus, solar energy investments have become quite suitable for increasing the synergy in hybrid energy projects. Furthermore, necessary research should be conducted to make biomass energy more efficient