Psychological adaptation to ambient temperatures is fascinating and critical, both theoretically and practically, for energy efficiency in temperate climates. In this study, we investigated and compared the brain response (event-related potentials with a late positive component and latency ~300 milliseconds; labeled “P300” in the present study) and reaction times of Indonesian participants (n = 11), as tropical natives living in Japan, and Japanese participants (n = 9) in natural (i.e., hot during the summer and cold during the winter) and comfort conditions (with cooling and heating). Thermal comfort under contrasting conditions was studied using both instruments and subjective ratings. P300 potential and reaction time were measured before and after a Uchida−Kraepelin (U−K) test (30 summation lines). The results showed that P300 potential and latency did not change between the pre- and post-U−K test among conditions in any of the groups. Furthermore, Indonesian participants showed low... [more]

Citizens are beginning to play a key role in the development of the smart city concept, providing a wealth of information for the sustainable development of cities. For this research, we planned and conducted empirical studies to examine the areas influencing the quality of life from the point of view of municipalities. A questionnaire form was developed and a survey was conducted on a sample of 84 municipal offices in Poland. We tabulated, statistically processed and analysed the results and thoroughly investigated the areas influencing the quality of life, their impact and importance. We determined which areas of the city are included in municipal research and checked whether there was a need to expand these areas. We found that the people responsible for research in municipal offices are aware that the quality of life is influenced by many areas and conditions. However, these people only choose selected areas for research and have a problem with indicating what can be extended to th... [more]

Small Island Developing States (SIDSs) are faced with challenges such as reducing the share of fossil energy and waste landfilling. This work summarizes the main aspects of 53 SIDSs that constrain economic development, energy sources, and waste management strategies. An integrative bibliographical review is conducted to synthesize the state-of-the-art of waste-to-energy (WtE) strategies and compare the technologies in light of their suitability to SIDS. The findings show that considering the large amount of waste produced annually, WtE technologies are of the utmost importance to reduce ecological footprints (EFs) and greenhouse gas (GHG) emissions, and to increase the share of renewable energy with the installation of incineration plants with energy recovery to replace fossil fuel power plants. Although WtE is recommended for all SIDSs, the Atlantic, Indian Ocean, Mediterranean, and South China Sea (AIMS) countries exhibit higher population density (1509 inhab/km2) and a high share of... [more]

In this study, modern nitrogen steels used for the manufacture of rings for Honda engines (70CC, 90CC, CRF70F, XL70, XR70, C70, CT70, ATC70, CL70) as well as other transport tribotechnical units was investigated. Due to the present ecological situation in the world, new environmentally friendly lubricating fluids for nitrogen steels’ tribotechnical units and surface treatments have been proposed. The results of tribotechnical tests are presented in the form of diagrams, graphs and step polynomials obtained by mathematically describing the changes in wear intensity when the load changes for different lubricating fluids. Friction pairs were compared with ShellHF-E 46 (synthetic lubricating fluid), ShellHF-R (biological origin) and lubricating and cooling liquids with 1%, 3% and 5% vegetable oil concentrations. In tribocoupling it was found that hydrogen diffuses into the metal because the tribodestruction of lubricating coolants plays an active role in the destruction of friction surface... [more]

Energy-saving and efficiency represent a crucial role in achieving a clean environment as well as economic and social development, providing substantial benefits to stakeholders, including householders. Better cost savings can be achieved by simply changing behavior. However, real energy users lack proper technical energy knowledge, awareness, and education in most cases. In most countries, women are involved in a higher percentage of energy activities in household chores but have less gender participation in energy decisions. In this regard, a gender perspective effectively understands energy users’ pragmatic and strategic needs for energy-saving behavior improvement. Previous literature reviews have been focusing on specific aspects of energy sustainability; however, no review has focused on energy-saving from a gender perspective to the best of our knowledge. It aims to provide a systematic review of literature on energy-saving and management, highlighting the importance of gender r... [more]

The poor indoor air quality (IAQ) of severely polluted toilets is associated with increased risk of severe disease. This study aimed to evaluate the overall IAQ according to the contaminant removal efficiency, volume average concentration, and breathing zone control level. The characteristics of contaminant transmission in a non-flushing ecological toilet (NFET) were analyzed using the computational fluid dynamics (CFD) methodology, and the proposed model was further validated based on experimental measurements. Both an orthogonal experimental design and CFD were used to analyze factors such as exhaust fan position (EFP), air change rate per hour (ACH), natural vent location (NVL), and grid height (G-h). The EFP and ACH were demonstrated to be the dominant factors affecting the IAQ, whereas NVL and G-h were found to play key roles. Single-factor analysis based on the significance levels of the ACH, EFP, and NVL was conducted using the CFD methodology to define three exhaust behaviors—n... [more]

Many high speed applications employ a surface permanent magnet (PM) machine topology with a retaining sleeve due to its robustness and ability to achieve high overall peripheral speeds as well as efficiencies. One often overlooked feature in the mechanical design of such machines, which has not achieved sufficient attention to date is the anisotropic thermal expansion of rare earth magnets, the degree of which varies for different magnet technologies. This paper investigates the effects of the aforementioned on the mechanical design of a high speed PM spindle machine with NdFeB magnets. The maximum allowable interference is found to be limited by the working temperature of the magnets while the minimum required interference is increased due to their anisotropic thermal expansion. Based on this, appropriate conditions are formulated to integrate a Neodymium Iron Boron (NdFeB) PM in high speed rotors. These modifications considering the shaft together with the magnet anisotropic thermal... [more]

The environmental performance of a combined cooling, heating, and power system is analyzed in this study at a component-level using a SPECO-based exergoenvironmental analysis. The engine consumes natural gas and produces 168.6 kW net power. The waste heat is recovered by a LiBr-H2O absorption chiller and a heat exchanger, which are used for cooling and heating purposes. The energy system is assisted by a solar field. An environmental Life Cycle Assessment quantifies the environmental impacts of the system, and these data are combined with exergy evaluations. The highest total environmental impact rate, 23,740.16 mPt/h, is related to the internal combustion engine, of which pollutant formation is the primary source of environmental impact. Compared with a non-renewable energy system, the solar-assisted trigeneration system decreased the environmental impact per exergy unit of chilled water by 10.99%. Exergoenvironmental performance can be further improved by enhancing the exergy efficie... [more]

Current EU policy will force a significant reduction of hard coal mines in the near future due to environmental restrictions. There are also numerous non-coal underground mines that will be excavated in the next few years. Taking the above into consideration, it is worth starting to plan further steps in terms of reclamation of these facilities. Within this manuscript, both recently used and novel approaches to underground space reclamation have been reviewed. Selected methods of reclamation were analyzed in terms of their strengths and weaknesses, and the results were compared with the effect of a commonly used approaches (i.e., filling or flooding of underground space after mine termination). The analysis has been performed in the scope of sustainable development. Taking into account the opinion of many stakeholder groups and underground facilities, reuse was considered as an action aimed at fulfilling sustainable development goals and the circular economy concept. Based on numerous... [more]

The study examined the impact of different factors on greenhouse gas (GHG) emissions, by applying the extended STIRPAT model and decoupling analysis for Tunisia for the period 1990−2018. Furthermore, the study utilizes Tapio decoupling model, and the Auto-Regressive Distributed Lag (ARDL) bounds test approach to examine the relationship between the variables of greenhouse gas (GHG) emissions, economic growth, energy consumption, urbanization, innovation, and trade openness. The findings validated an inverted U-shape relationship between GDP and GHG emissions. In addition, we find that the consumption of renewable energy contributes to the reduction of GHG emissions in the long run. The findings call authority for the adaption of the regulatory framework relating to energy management, energy efficiency and the development of renewable energies, as well as to initiate energy market reforms, implement mitigation strategies and encourage investments in clean energies.

The development of the world economy goes hand in hand with increased energy consumption and global warming caused by greenhouse gases. These issues can be tackled by implementing promising technologies of power generation. They differ from the known ones in that new energy resources are involved, e.g., mixtures of various types of biomass, provided that hazardous gas emissions during the production process are minimized. The development of high-potential energy-efficient and environmentally friendly technologies which use biofuel in the energy industry requires scientific evidence for the mechanisms, conditions, and characteristics of physical and chemical processes during pyrolysis and gasification of biomass, including its multicomponent types. This article analyzes the world technologies and research findings in the field of biomass pyrolysis and gasification. The effect of a group of factors on the intensity and completeness of gasification and pyrolysis of biofuel compositions ha... [more]

The quality of outdoor air in many places, especially in urbanized areas, is bad; therefore, a series of studies aimed at assessing the impact of outdoor air parameters on indoor air quality was conducted. Four nurseries (three buildings) located in different parts of Poznań, Poland were selected as research sites. During the research period, the concentrations of CO2, PM2.5, and PM10 inside and outside the buildings over time were analyzed. Measurements outside the buildings were supplemented with an analysis of traffic near nurseries and an assessment of pollutant emissions from vehicles of various categories. Measurements were conducted during the COVID-19 pandemic in a weekly series during winter (December)—(W), spring (April)—(S), and at the end of spring (June)—(LS). Testing and analyses indicated poor indoor air quality in three out of four nurseries. To ensure indoor air quality at the proper level, it is necessary to supply rooms with outside air. Ventilating rooms by airing,... [more]

The paper places emphasis on primary energy resources, their covariation, and their correlation with socioeconomic factors and aims to provide a systematic analysis of their development over time. The analysis uses evidence from European Union (EU) country-level data and is based on visual analytics techniques. Different results from the same territories show that energy consumption does not always reflect or is due to climatological or meteorological conditions. Extensive use of visualization is adopted as a means of contributing to the understanding of energy use, some involved problems and concepts, and energy consumption trends over time. We present an approach that addresses the informatics challenges based on the integration of visualization software, data integration, and cluster analysis. Our cross-sectional energy review advocates that EU energy leaders are moving towards a low-carbon economy. The correlations of energy variables with economic and pollution effects are stronge... [more]

The aim of the manuscript was to present the collective results of research on the profitability of using various renewable sources in Poland with the greatest development potential. In the paper, the economic parameters of various investment projects were determined and calculated, i.e., Net Capital Value (NPV), Internal Rate of Return (IRR) and the Period of Return on Invested Capital (PBT). The economic assessment of the use of RES technologies was supplemented with the assessment of environmental benefits. The ecological criterion adopted in the study was the assessment of the potential and costs of reducing greenhouse gas emissions as a result of replacing fossil fuels with renewable energy technologies. On the basis of the constructed economic model to assess the profitability of investments, it has been shown that the analyzed projects will start to bring, depending on their type and technical specification, measurable economic benefits in the form of a reduction in the amount o... [more]

The need for advancements in residential construction and the hazard induced by the shrink−swell reactive soil movement prompted the development of the prefabricated footing system of this study, which was assessed and compared to a conventional waffle raft using a multi-criteria analysis. The assessment evaluates the structural performance, cost efficiency, and sustainability using finite element modelling, life cycle cost analysis, and life cycle assessment, respectively. The structural performance of the developed prefabricated system was found to have reduced the deformation and cracking by approximately 40%. However, the cost, GHG emission, and embodied energy were higher in the prefabricated footing system due to the greater required amount of concrete and steel than that of the waffle raft. The cost difference between the two systems can be reduced to as low as 6% when prefabricated systems were installed in a highly reactive sites with large floor areas. The life cycle assessme... [more]

Achieving zonal isolation along wellbores is essential for upholding the containment integrity of subsurface reservoirs and preventing fluid seepage to the environment. The sealing performance of Portland cements conventionally used to create barriers can be severely compromised by defects like fractures or micro-annuli along casing−cement−rock interfaces. A possible remediation method would be to circulate reactive fluids through compromised cement sections and induce defect clogging via mineral precipitation. We assess the sealing potential of two prospective fluids: sodium bicarbonate and sodium silicate solutions. Reactive flow-through experiments were conducted on 6-m-long cemented steel tubes, bearing ~20-μm-wide micro-annuli, at 50 °C and 0.3−6 MPa fluid pressure. For the sodium bicarbonate solution (90 g/kg-H2O), reactive flow yielded only a minor reduction in permeability, with values remaining within one order. Injection of sodium silicate solution (37.1 wt.%, SiO2:Na2O molar... [more]

Reducing the harmful effects on the environment and increasing the expression of sustainable development principles is one of the most topical challenges all around the world. Given the importance of logistics for the economy and the growing concern for the environment, the purpose of this article was to reveal a green logistics (GL) practice framework for sustainable development. Based on a systematic and comparative analysis of the scientific literature, the authors present a theoretical conceptual model for applying GL practices to sustainable development. In order to assess the expression of GL practices and their determinants in Lithuanian transport and logistics services companies, a quantitative questionnaire survey was conducted. Descriptive statistics, correlation, and regression analyses were used to analyze the data. The results made it possible to identify GL areas such as green transportation, green warehousing, green management, sustainable waste management, and the preva... [more]

Slow steaming is an operational measure in ocean-going vessels sailing at slow speeds. It can help climate mitigation efforts by cutting down marine fuel consumption and consequently reducing CO2 and other Greenhouse Gas Emissions (GHG). Due to climate change both the European Union (EU) and the International Maritime Organization (IMO) are analysing the inclusion of international shipping in the EU Emissions Trading System (ETS) in the near future or alternatively implementing a carbon tax. The paper proposes a methodology to decide the optimal speed of a vessel taking into account its characteristics and the factors that determine its economic results. The calculated cash flow can be used in valuation models. The methodology is applied for a case study for any container ship in a range from 2000 to 20,000 Twenty-foot Equivalent Units (TEU) on a leg of a round trip from Shanghai to Rotterdam. We calculate how speed reduction, CO2 emissions and ship owner’s earnings per year may vary b... [more]

The purpose of this paper is a multidimensional assessment of the diversification of economic development in EU countries in the context of the progress in the implementation of the concept of sustainable development in 2014 and 2019. The issues discussed in this article are topical and important, given that the spatial disparity of economic development in the EU has never been so pronounced as it is today. While there is a wealth of studies on economic development in the literature, research on the comprehensive approach to this problem in the relation of sustainable development appears to be rather scarce. The article emphasizes the role of energy in economic growth. Authors used taxonomic measures. They were constructed on the basis of selected methods of multidimensional comparative analysis. By using the Hellwig method and the TOPSIS method, taxonomic measures were constructed, and linear ordering of the EU countries was carried out. In addition, using the so-called threshold meth... [more]

The recycling of waste products is an important way to achieve global sustainable development. To analyze the impact of different objects of government subsidies on single-channel recycling based on recycling propaganda, four theory game models of single-channel recycling based on government subsidies and recycling propaganda are established. By comparing and analyzing the effects of different subsidies and propaganda strategies on the recycling of waste products in the four models, this article mainly draws the following conclusions: the government selecting different objects to subsidize has the same effect on the unit recycling price, quantity, and revenue of waste products; when the government subsidizes the processors, the consigned recycling price of waste products will increase, but when the government subsidizes recyclers, it will decrease; when the propagandist is determined, the optimal value of propaganda is related to the sensitivity of residents to the unit recycling price... [more]

The exploitations of deep-water wells often use directional well drilling to reach the target layer. Affected by special environments in deep water, the prediction of pressure loss of cement slurry is particularly important. This paper presents a prediction model of pressure loss suitable for deep-water directional wells. This model takes the complex interaction between the temperature, pressure and hydration kinetics of cement slurry into account. Based on the initial and boundary conditions, the finite difference method is used to discretize and calculate the model to ensure the stability and convergence of the result calculated by this model. Finally, the calculation equation of the model is used to predict the transient temperature and pressure loss of Wells X1 and X2, and a comparison is made between the predicted value and the monitoring data. The comparison results show that the maximum error between the temperature and pressure predicted by the model and the field measured valu... [more]

The photovoltaic cell surface in linear hybrid concentrated solar collectors receives non-uniform radiative flux, causing additional thermal stress due to hot spots and reducing its electrical performance and durability. The current study proposes a parametric methodology to determine the optimal receiver displacement required in a linear Cassegrain-type hybrid solar collector. The aim was to achieve a minimal non-uniformity distribution and a high radiative flux over the photovoltaic cells, considering optical errors close to real environment conditions and analyzing the heat transfer to determine the electrical and thermal efficiencies. The developed methodology was applied to analyze a case study with a receiver width of 0.125 m and rim angle of 80° and using a commercial silicon photovoltaic cell that supports up to 7000 W/m2. After applying the methodology, a hybrid solar collector with a concentration ratio of 13.0 and receiver displacement of 0.14 m is recommended. As a result,... [more]

The world is currently witnessing a rapid increase in sewage sludge (SS) production, due to the increased demand for wastewater treatment. Therefore, SS management is crucial for the economic and environmental sustainability of wastewater treatment plants. The recovery of nutrients from SS has been identified as a fundamental step to enable the transition from a linear to a circular economy, turning SS into an economic and sustainable source of materials. SS is often treated via anaerobic digestion, to pursue energy recovery via biogas generation. Anaerobically digested sewage sludge (ADS) is a valuable source of organic matter and nutrients, and significant advances have been made in recent years in methods and technologies for nutrient recovery from ADS. The purpose of this study is to provide a comprehensive overview, describing the advantages and drawbacks of the available and emerging technologies for recovery of nitrogen (N), phosphorus (P), and potassium (K) from ADS. This work... [more]

The increasingly frequent use of electric drives is a new direction of development in personal transport. Sometimes these drives take over the work of human muscles, and sometimes they only support them. This is particularly evident in means of transport such as bicycles and scooters, but also in transporting people with disabilities. This study questions whether this is the only right development direction, and explores the possibility of developing means of transport for the more effective use of human muscles by proposing new structural solutions. We identified that such an action favors the minimization of the environmental load generated by technical facilities and, at the same time, may be a response to social needs resulting from the principles of sustainable development. This paper presents the operation principle of the innovative Wheelchair Cam-thread Drive (WCD), followed by field tests, laboratory measurements and biomechanical analyses of the WCD, comparing it with a typic... [more]

The by-product gases from the blast furnace and converter of an integrated steelworks highly contribute to today’s global CO2 emissions. Therefore, the steel industry is working on solutions to utilise these gases as a carbon source for product synthesis in order to reduce the amount of CO2 that is released into the environment. One possibility is the conversion of CO2 and CO to synthetic natural gas through methanation. This process is currently extensively researched, as the synthetic natural gas can be directly utilised in the integrated steelworks again, substituting for natural gas. This work addresses the in situ methanation of real steelworks gases in a lab-scaled, three-stage reactor setup, whereby the by-product gases are directly bottled at an integrated steel plant during normal operation, and are not further treated, i.e., by a CO2 separation step. Therefore, high shares of nitrogen are present in the feed gas for the methanation. Furthermore, due to the catalyst poisons pr... [more]