VGTU Journals (Vilnius Gediminas Technical University - Vilnius Tech)
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The approach to optimization of the structure of the repair process of aviation radio equipment
No full textThe Operation System (OS) of Aviation Radio Equipment (ARE) includes such elements as equipment, organizational structure, processes, documentation, personnel, measuring equipment, consumables and information resources, and others. When considering the problems of primary design and modernization of OSs, a large number of problems arise that can be solved with the help of intelligent decision support systems. During the operation of ARE, significant material resources are consumed, the amount of which is usually random. Therefore, during design, one of the main tasks is to ensure the minimum costs. This article considers the task of cost optimization within the organizational structure of the repair process. At the same time, the article provides analytical equations that allow to calculate and estimate operational costs for a given organizational structure, tariffs for repair and delivery of equipment components, and failure flow parameters. Attention is also paid to the task of rationalizing the organizational structure of the repair process, taking into account the efficiency of the decision-making procedures depending on the failure type (simple or complex). In addition, the article considers an example of several scenarios for the possible placement of repair enterprises in the airports of Ukraine during the post-war reconstruction period
The link between the shadow economy and the happiness economy in EU euro area countries
No full textPurpose – the aim of this study is to assess the relationship and influence between the shadow economy and the level of happiness in the Euro area economies of the European Union by highlighting the theoretical assumptions behind the concept and expression of the shadow economy and happiness.
Research methodology – to calculate the size of the shadow economy will be used Gutmann’s index. To calculate the happiness of the economies will used the Happiness Economy Index from the World Happiness Report (2022) including the following 6 indicators (GDP per capita, healthy life expectancy (that derives to life expectancy and mental health evaluation), social support, freedom index, generosity (do-nations to charity), and corruption index. To determine the relationship between the shadow and happiness economy, the Granger causality method.
Research limitations – the study’s limitations include data reliability and accuracy, methodological limitations, geographical and cultural differences, and time constraints. The estimation of the size of the shadow economy and the happiness economy index may contain inaccuracies, and the Granger causality method cannot fully confirm causality. The study is limited to the euro area countries of the European Union; therefore, the results may not be fully applicable to other countries. Additionally, the data may not fully capture long-term trends or developments.
Practical implications – the results of this study can help policymakers and economists better understand how to reduce the size of the shadow economy and thereby increase people’s happiness. The study’s findings indicate a positive correlation between a country’s Happiness Economy Index and the size of its shadow economy. This suggests that investing in people’s well-being can positively impact the formal economy. Furthermore, the study’s findings can inform the development of effective strategies to combat the informal economy. For instance, strategies such as enhancing social support, increasing the freedom index, and combating corruption can potentially reduce the size of the informal economy and improve the overall economic situation in a country.
Findings/Value – the research confirmed the hypothesis that the size of the shadow economy is smaller in countries with a higher happiness economy index. And Granger causality tests show that the shadow economy has a relatively strong effect on happiness in the EU euro area countries
Component definition innovation plan as a tool to allow flight simulator training device roadmapping
No full textThe use of flight simulators as a complement to pilot training offers significant advantages in reducing costs and risks associated with aircraft accidents, in addition to increasing safety and situational awareness during the practical phases of flight. However, the development of equipment to support pilot training has been carried out with an exclusive focus on this application, overlooking the exploration of alternative uses or new business opportunities that could diversify revenue streams and foster innovation. In this study, a method was developed to identify components that support the Technology Roadmapping process. The application phases are described, and each step is illustrated with a case study on developing a flight simulator training device. The results present potential markets, products, technologies, resources, and partners, forming a framework for innovation planning in aeronautical flight training. Specifically, the potential for implementing affordable full-motion flight simulators is examined, including applications in amusement parks for leisure, incentive flights for new crew, providing a passenger flight experience in the context of advanced air mobility, and, primarily, referencing flight centers to enhance airmanship skills and flight safety
Is digital technology innovation a panacea for carbon reduction?
No full textThis paper analyses the impact of digital technological innovation on the carbon emission intensity of enterprises and conducts an empirical test based on the data of listed enterprises in China from 2009 to 2021. The study finds that (1) digital technological innovation can significantly reduce carbon emission intensity. (2) Enterprises’ digital attention and investment can significantly increase their operating income but not reduce carbon emissions. Digital technology patents can significantly reduce carbon emissions in the short term. In the long run, even new digital technologies will have a carbon rebound effect once they are deployed on a large scale. Therefore, digital technology innovation is still challenging in the long run to realize the synergy effect of “increasing production and reducing carbon.” (3) Mechanism tests show that digital technology innovation can reduce carbon intensity by improving operational efficiency, promoting cleaner production, and improving human capital. (4) If the government pays moderate attention to digital development, digital technological innovation by enterprises can significantly reduce carbon intensity. Meanwhile, this effect is more significant in regions with higher levels of intellectual property protection. Digital technology innovation can significantly reduce carbon intensity for mature, high-tech, and technology-intensive enterprises.
First published online 18 November 202
Is the process of graduation of least developed countries (LDCS) suitable and sufficient?
No full textMillions of people are living in the Least Developed Countries (LDCs), the poorest of the poor. Getting them out of that situation is one of humanity’s most urgent tasks. Since 1971, the United Nations has recognized LDCs as a category of countries characterized by, among others, dependence on international trade, rapid population growth, low literacy, an unskilled labor force and poorly developed institutions. This research analyzes the patterns in the evolution of a group of LDCs that have led them to graduation. This paper assesses whether the established way to leave this group of countries is realistic and foundational for future progress. The paper is organized as follows: Section 1 is a brief introduction on LDCs and their characteristics, Section 2 presents the method applied to obtain the results, focusing on criteria that must be met; Section 3 provides the results for the countries in the graduation process; Section 4 includes a discussion and comments on the results; Section 5 summarizes the main findings and draws conclusions. Additionally, a bibliographical review of the literature consulted is provided.
First published online 18 March 202
Economic consequences of the phenomenon of uberization on the example of the services of selected carriers in the transport industry
No full textUberization is a process, phenomenon, trend, and direction that emerged in the 21st century economy thanks to Uber Technologies, Inc., which was the first to introduce a mobile application that connects drivers and passengers. Although the name of the trend was not formalized by the Uber corporation, it appeared a few years later to describe certain dependencies that emerged in the economy and that gained importance not only in the field of transportation services, but also in the field of finance, in the labor market, or in relation to the real estate market. The purpose of the study was to determine the impact of the progressive phenomenon of uberization on the competitiveness of the transportation industry in the pre-pandemic period and in the post-pandemic period. The study assumed the hypothesis that carpooling services, which are one of the important models of uberization, implemented in Poland through the BlaBlaCar app, can be a significant competitor to transportation services provided through traditional forms and models of communication, i.e., train and bus connections. The results of the study showed that BlaBlaCar services are a cheaper alternative to other means of transportation, i.e., public transport (Polskie Koleje Państwowe, PKP Intercity) and bus connections, although not always. As a rule, their competitiveness is higher for those routes and trips where there are many drivers offering free space in the car. On the other hand, on the routes less frequently visited by BlaBlaCar drivers, fares with a BlaBlaCar driver are higher than rail and bus fares. The considerations of the article meet the objectives of the cognitive goal and the application goal and showed that uberization in the transport industry is a significant phenomenon that is still developing and, in the future, may threaten traditional forms of transport, i.e., rail and bus travel
Harmonization of marine gravity data in Eastern Baltic
No full textMarine gravity datasets covering areas of state scale typically are made up of data that has been surveyed over multiple campaigns. These campaigns often take place many years apart, are of varying resolution and accuracy. This is due to ship-borne campaigns being much more expensive and time consuming than the ones on land; because of this, there is added value in validating and possibly correcting older data sets.
Over the course of recent BalMarGrav marine gravity project, dense, high quality gravity data was obtained covering most of the Latvian exclusive economic zone. The new data have been compared to campaigns, both as means of new data validation, and to check for possible biases among older data sets. Purpose of this research is to further the effort, to provide wider coverage of old marine gravity points, to test automated gravity point digitization, and to perform inter-campaign comparisons, using new, filtered and more precise data.
Data recovered during this research covers the previous data gaps between sets used in previous research. Using a more complete data coverage can improve new campaign data set validation and provide insights on inter-campaign biases within older data. Recovered data cover shallow coastal areas, where gravity mapping was not done over BalMarGrav project. Thus, by applying correctional values geoid errors can be minimized in the problematic transition zone between terrestrial and marine data.
Survey reports containing 20th century marine gravity point data were digitized, using optical character recognition. Gravity point values were transferred to sea surface and transformed to modern reference frames. Both modern and historic marine gravity data were filtered for gross errors and bias tracks. Data set robustness was checked, using leave-one-out cross validation. After processing, a comparison was made between old and new data.
Results present re-processed and filtered marine gravity datasets, and their comparison statistics. Comparison statistics before and after filtering reveal the increased accuracy and precision of filtered data. Mean comparison values reveal inter-campaign biases and provide correction values, which can increase data accuracy for use as input in future research and surface modelling
Does China’s housing supply-demand relationship impact urban innovation capability
No full textUnlike existing literature that explores the impact of house prices on urban innovation, this paper skillfully examines the relationship between the housing market and urban innovation from the perspective of the housing supply-demand (S-D) relationship. Utilizing panel data from 284 prefecture-level cities in China spanning from 2005 to 2020, this study investigates the respective impacts of housing supply, housing demand, and their interplay on urban innovation capacity (UIC). Our findings indicate that housing supply positively influences UIC, with a coefficient of 0.060; specifically, for every 1% increase in housing supply, UIC increases by 0.06%. Similarly, housing demand also significantly affects UIC, with a coefficient of 0.060, suggesting that a 1% increase in housing demand corresponds to a 0.060% rise in UIC. However, we observe a significant negative effect of the housing S-D relationship on UIC, with a coefficient of –0.049, indicating that an increase in the housing S-D ratio detrimentally impacts urban innovation. Furthermore, our analysis reveals that as the housing supply-demand ratio rises, house prices also tend to increase. Additionally, we identify heterogeneity in our results, indicating variations in the housing supply-demand ratio’s impact on the innovation capacity of cities across different regions
A new e-commerce model for free-riding behavior in decentralized supply chains
No full textThe complexity of consumer free-riding behavior is a current significant problem, as modern online purchasing channels sharply compete with the traditional ones. The purpose of this study is to examine the impact of showrooming behavior by free-rider consumers on product valuation within a decentralized supply chain. Also, we examine how the consumers’ use of the benefits of the experience achieved in the offline channel to buy from the online channel influences their product valuation in a decentralized supply chain and influences the profits’ level of offline retailers. We develop an e-commerce model for product valuation when customers visit a brick-and-mortar unit for products and then buy them online. Results have indicated that the free-riding customers’ product valuation is between online and offline customer product valuations and the price at which the customer becomes a showrooming customer is influenced not only by the offline price, but also by the degree of the online channel acceptance and the shopping services value factor. This study has managerial consequences in decision-making of sellers, especially for traditional stores which to maximize the profit must optimize the offline additional services, to reduce the phenomenon of free-riding and at the same time not to generate additional costs
Single real estate developers’ innovations in housing design: an historical exploration based on China Vanke Co. Ltd.
No full textThis paper focuses on the practices, innovations and design regarding housing supply developed by a single Chinese private real estate company, China Vanke Co. Ltd. between 1979 and 2016. In the last 5 decades, China experienced a period of rapid urbanization, accompanied by the introduction of numerous economic and institutional reforms impacting the nation’s model of housing supply. Significant changes disrupted the urban housing sector in the country, shifting the main supply system from a public welfare model to a market-driven one. Within this time span, most new residential properties were developed and marketed by large real estate enterprises, which became crucial players in establishing the new housing market. While there is an extensive body of literature examining China’s housing market formation and progression, most of these studies focus on the economic and social aspects of housing, including factors such as affordability, inequality, governance, preferences and choices. Single real estate firms’ innovations, as well as the links between housing designs and market supply and demand, have yet to be thoroughly explored. This latter area represents thus the main focus of this paper. Expanding from the specific case of Vanke, this paper seeks to discuss the innovative processes of a real estate enterprise and the role of a single company in shaping new housing designs, based on supply and demand transformations