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Found 6412 publications
Enhanced discrete bacterial memetic evolutionary algorithm - An efficacious metaheuristic for the traveling salesman optimization
Publication Name: Information Sciences
Publication Date: 2018-09-01
Volume: 460-461
Issue: Unknown
Page Range: 389-400
Description:
In this paper we present a novel universal metaheuristic, Discrete Bacterial Memetic Evolutionary Algorithm (DBMEA), which is based on the combination of the Bacterial Evolutionary Algorithm and local search techniques, used for solving NP-hard optimization problems. The algorithm was tested on a series of symmetric Traveling Salesman Problems (TSP) and Traveling Salesman Problem with time windows (TSPTW) benchmarks. The size of the symmetric TSP benchmarks went up to 5 000 cities. In all cases the DBMEA algorithm produced optimal or near-optimal solutions and the difference from the known best values was within 0.16%. While for large size problems it was much faster than the Concorde solver, it was found to be slower compared to the Helsgaun-Lin-Kernighan heuristic, which is the most efficient TSP solver method. With some slight modifications the same algorithm was also tested on TSP with time windows (TSPTW) benchmark instances. In most cases the DBMEA procedure found the known best solutions, and it was again the second fastest method compared with the state-of-the-art techniques for the TSPTW. DBMEA is called efficacious because it is a universal method. It can be efficiently applied to various NP-hard optimization problems and, as in all cases, it results in the optimal or a very near-optimal solutions, while its runtime is very predictable in terms of the size of the problem, and the topology of the instance does not affect its runtime significantly. Even though heuristics developed for a particular type of problem might perform better for that restricted class, our novel method proposed here is universally applicable and may be deployed successfully for optimizing other discreet NP-hard graph search and optimization problems as well.
Open Access: Yes
Ecological footprint at the micro-scale-how it can save costs: The case of ENPRO
Publication Name: Resources
Publication Date: 2018-09-01
Volume: 7
Issue: 3
Page Range: Unknown
Description:
The Ecological Footprint (EF) has become a very popular alternative indicator of development in the last three decades. It can be widely used to show the unsustainability of total and individual levels of consumption in countries. But can EF be a meaningful indicator at the micro level as well This paper presents an argument on this issue. Based on a literature review including our own analysis and the correlation of EF with GDP and other alternative indicators, EF is evaluated at the macro level. Then, an original case study is presented, underpinning the applicability of EF on the company level, linking the ordinary corporate carbon footprinting with the EF method. Based on the findings, micro level EF calculations can help organizations in finding fields of intervention (inefficiencies and emission hotspots). EF accounting can also be used to evaluate the economic benefits of such measures after their realization.
Open Access: Yes
Therapeutic role of physical activity in relationship between chronic pain and sleep quality in musculoskeletal disorders
Publication Name: Orvosi Hetilap
Publication Date: 2026-02-01
Volume: 167
Issue: 8
Page Range: 300-308
Description:
Musculoskeletal diseases represent a major public health problem worldwide, as they are associated with pain, reduced musculoskeletal function, and diminished quality of life. They affect more than 1.7 billion people globally, and their prevalence continues to rise due to ageing, obesity, sedentary lifestyle, and psychosocial factors. Chronic pain is the most common complaint, which may appear as an independent condition or as a consequence of other diseases such as osteoarthritis, spondylosis, or rheumatoid arthritis. Pain and sleep disturbances are closely and mutually related: inadequate sleep increases pain sensitivity, reduces the efficiency of pain processing, and contributes to the persistence of chronic pain. The aim of this review study is to examine the relationship between pain, the most common symptom of degenerative joint and spinal diseases and sleep quality. Sleep disorders are highly prevalent in certain musculoskeletal diseases and predict a subsequent decline in functional status. Therapeutic options include balneotherapy and complex physiotherapy, both of which have been shown to reduce pain and improve musculoskeletal function. Several studies have reported long-term benefits of balneotherapy, mud therapy, and aquatic physiotherapy. In addition, regular moderate-intensity physical activity plays a key role in reducing pain and improving functional status and sleep quality. Monitoring physical activity using questionnaire-based methods and objective wearable devices enables a more accurate assessment, safe planning, and continuous tracking of physical activity levels. Overall, a multimodal, individualized therapeutic approach is the most effective in the management of musculoskeletal diseases, targeting the simultaneous improvement of pain, sleep, and lifestyle-related factors. Orv Hetil. 2026; 167(8): 300–308.
Open Access: Yes
Effect of Self-driving Buses on Vehicle Scheduling
Publication Name: Advances in Intelligent Systems and Computing
Publication Date: 2021-01-01
Volume: 1278
Issue: Unknown
Page Range: 21-29
Description:
We are more and more close to the time when a higher number of autonomous vehicles are appearing in road traffic. The number of unanswered questions does not diminish but grow. One such issue is the role of autonomous vehicles in public transport. When talking about autonomous vehicles we often think of only cars and we think less about self-driving buses. But the economic potential inherent in autonomous buses is huge. In the Hungarian vehicle and crew scheduling practice (and also in other countries) the one driver-one vehicle control is typical. This method closely links the vehicles and the drivers. Vehicles should therefore adapt to the rest time of the crew and the employment rules. Unused reserves are generated in the system. Autonomous vehicles can release this overcapacity. Thanks to that, fewer vehicles can carry out public transport tasks and we can save extra rides. It also provides a solution to the lack of drivers, which is a basic problem in many countries. In our study we show the reserves that can be recovered from the system in the case of three Hungarian cities (Eger, Dunaújváros, Győr). We show how much savings can be achieved by running autonomous buses in European cities with a population of 45 000, 54 000 and 130 000 inhabitants. The results are promising. In smaller cities we could achieve about 20% of economical savings but in bigger cities 40% is also realistic. Our statements are based on only rough calculations and they try to help in preparation for the future.
Open Access: Yes
QUALITY OF SCIENTIFIC ACTIVITY AS A DETERMINANT OF SOCIO-ECONOMIC DEVELOPMENT
Publication Name: Economics and Sociology
Publication Date: 2022-01-01
Volume: 15
Issue: 3
Page Range: 301-318
Description:
The purpose of this work is to identify the functional links between key indicators of scientific activity and socio-economic development and to check whether the quality of scientific activity and the dynamics of innovative development are the key determinants of socio-economic progress. Following the chosen methodology, the paper forms an array of input data that characterizes the level of scientific and innovative activity, economic and social development. The principal component method is used to identify the most relevant indicators from each group and to introduce three latent variables that denote each group separately. A system of simultaneous structural equations is obtained as a result of establishing functional relationships between manifest and latent variables and building a structural model. In addition, the paper determines two clusters of the studied countries to confirm the obtained results through structural modelling. The study is conducted for 35 European countries based on 33 indicators, which characterize the quality of scientific activity, economic and social development during 2014-2020. The obtained system of structural equations confirms the hypothesis regarding the importance of scientific activity quality in terms of ensuring the socio-economic development of the country.
Open Access: Yes
Gender-Inclusive Rural Tourism: Women’s Participation in the Panji Ecovillage Homestay, North Bali
Publication Name: Jurnal Kajian Bali
Publication Date: 2025-12-05
Volume: 15
Issue: 3
Page Range: 1267-1299
Description:
Women of the Farmers Group in Panji Village, North Bali, do not only support their families through agricultural work but also convert spare rooms in their homes into homestays, forming the Women Ecovillage Homestay Group. Through this community, they learn collectively to engage in and benefit from village tourism. This initiative illustrates how rural women contribute simultaneously to economic improvement and cultural preservation. This study examines their roles in community-based tourism (CBT) and their contribution to small-scale sustainable tourism, emphasizing gender-inclusive village development. Fieldwork was carried out intermittently from 2023 to 2025 as part of a community service program, enabling continuous observation of participation and empowerment processes. Using action research, the researcher applied and tested strategies developed through FGDs with key stakeholders. The findings show that women in Panji Village play a central role in sustaining tourism by managing homestays while safeguarding cultural identity, offering a model for inclusive and gender-responsive rural tourism development.
Open Access: Yes
Experimental Analysis of a Turbocharger: Influence of Oil Supply Temperature and Pressure on the Bifurcation Phenomenon in Subsynchronous Frequencies
Publication Name: Lubricants
Publication Date: 2025-03-01
Volume: 13
Issue: 3
Page Range: Unknown
Description:
This study presents an experimental analysis of a turbocharger equipped with a semi-floating bearing system, with a particular focus on the bifurcation phenomenon within the subsynchronous vibration spectrum. A predefined design of experiments (DoE) methodology was employed to determine the measurement domains to be analyzed, where the primary input parameters included the lubricant supply temperature and pressure values. The bifurcation phenomenon in relation to the physical parameters of the system is observed via vibration and displacement sensors in two directions, enabling the collection of subsynchronous frequency data for further insights into the influence of lubricant parameters on the rotor system. While the nonlinear effect of oil temperature is well studied in the literature. However, the combined effect of oil supply temperature and pressure was not yet examined, which was the focus of the present study. This paper aims to investigate its coupled effects on the bifurcation phenomenon associated with both lubricant temperature and pressure. The occurrence of the introduced phenomenon is further examined to enhance the understanding of the uncharted behavior of turbocharger rotors and other rotor-bearing-based machinery.
Open Access: Yes
Investigation of glued insulated rail joints with special fiber-glass reinforced synthetic fishplates using in continuously welded tracks
Publication Name: Pollack Periodica
Publication Date: 2018-08-01
Volume: 13
Issue: 2
Page Range: 77-86
Description:
In this paper the authors partially summarize the results of a research on glued insulated rail joints with fiber-glass reinforced plastic fishplates (brand: Apatech) related to own executed laboratory tests. The goal of the research is to investigate the application of this new type of glued insulated rail joint where the fishplates are manufactured at high pressure, regulated temperature, glass-fiber reinforced polymer composite plastic material. The usage of this kind of glued insulated rail joints is able to eliminate the electric fishplate circuit and early fatigue deflection and it can ensure the isolation of rails' ends from each other by aspect of electric conductivity.
Open Access: Yes
An S-graph based approach for multi-mode resource-constrained project scheduling with time-varying resource capacities
Publication Name: Chemical Engineering Transactions
Publication Date: 2018-01-01
Volume: 70
Issue: Unknown
Page Range: 1165-1170
Description:
The Resource-Constrained Project Scheduling Problem (RCPSP) is a general problem class of scheduling problems. It even contains the well-known job shop scheduling problem as a special case. In these problems, jobs demand different amounts from multiple resources at once. The goal is to minimize completion time while satisfying resource capacity constraints throughout the schedule. The RCPSP has several variations and generalizations, one of which is the multi-mode problem. Multiple operation modes are given for jobs, differing in resource usages and execution times. Another generalization is where resources have time-varying capacities instead of a constant limit. The S-graph framework was developed for batch process scheduling and used successfully in various applications. The advantages of this approach motivate research to extend its capabilities to more general problem classes and apply it in various specialized case studies. The authors have previously presented an extension of the S-graph framework for RCPSP and its multi-mode generalization. In this work, a further extension is proposed for handling time-varying capacities. The method relies on a model transformation technique and recent algorithmic developments of the framework.
Open Access: Yes
DOI: 10.3303/CET1870195
