Wearable technology represents a new technological paradigm for promoting physical activity, enabling monitoring of performances and athletic gestures. In addition, they can be employed for remote health monitoring applications, allowing continuous acquisition of users’ vital signs directly at home, emergency alerting, and computer-assisted rehabilitation. Commonly, these devices depend on batteries which are not the better option since researchers aim for dispositive who need minimal human intervention. Energy harvesting devices can be useful to extract energy from the human body, especially by integrating them into the garments, giving health monitoring devices enough energy for their independent operation. This review work focuses on the main new wearable technologies and devices to scavenge energy from the human body. First, the most suitable energy sources exploitable for wearable applications are investigated. Afterward, an overview of the main harvesting technologies (piezoelect... [more]

Energy monitors are indispensable for achieving efficient electrical grids and even more so in the age of the Internet of Things (IoT), where electrical system data are monitored from anywhere in the world. This paper presents the development of a two-channel electrical parameter-monitoring system based on the M5 Stack Core2 kit. The acquisition of variables is done through PZEM 004T V3.0 sensors, and the data are sent to the ThingSpeak cloud database. Local readings are done through the LCD, and data re stored on a micro SD card. Remote monitoring is done through two applications, namely a web application and a mobile application, each designed for different purposes. To validate this proposal, a commercial device with IoT features (Gen 2 Vue Energy Monitor) is used, comparing the active power and active energy readings recorded continuously for 7 days. The results indicate an accuracy of up to 1.95% in power and 0.81% in energy, obtaining a low-cost compact product with multiple feat... [more]

CO2 is the most emitted greenhouse gas and is mainly produced by human activity. In fact, about 75% is emitted in cities and 40% of global carbon emissions is produced by the building sector. Therefore, buildings are very important in terms of CO2 emissions. This importance is also reflected in the works that have been developed on this subject. This manuscript reviews the research that has shown or calculated the amounts of CO2 emitted in buildings. For a better understanding of the scope of the investigations, a classification is presented. With this, it is intended to help researchers interested in this area by summarizing the studies carried out to date on the amounts of CO2 emitted depending on the type of building.

Fly ash from waste incineration and waste poplar bark from furniture manufacturing are domestic wastes. In this study, fly ash and poplar bark were used as raw materials to prepare activated carbon via carbonization, steam activation and reagent modification. The effects of the raw material mixing ratio, carbonization temperature, activator concentration and modifier concentration on the physicochemical properties of the semi-coke and activated carbon were investigated through experiments. The experiment showed that when the carbonization temperature was 300 °C, the steam concentration was 20%, the mixing ratio of the poplar bark and fly ash (B:F) was 5:1, and the modifier was 6% K2CO3 reagent and 9% CaCl2. The prepared activated carbon had a better yield, specific surface area and pore structure, and had an abundant surface functional group structure. This paper points out the direction for the industrial directional production of activated carbon adsorbents with excellent physical an... [more]

This work allows characterizing and classifying the consumption profiles of non-residential customers (without distributed generation) based on the consumption curves obtained from the records reported by 934 smart meters in the period from January to December 2019, and which belong to an electric power distribution company in Chile, SAESA Group S.A. To achieve the characterization and classification of the consumption profiles, three typical days are analyzed and determined, which correspond to working days (Monday to Friday), Saturdays, and Sundays or holidays. These three typical days are analyzed for each trimester of 2019. The data processing is carried out on the Power Bi and Matlab® platforms. In Power Bi, the data provided by the electricity company are worked, obtaining the average consumption curves for each client in each period of study considered, while in Matlab®, the visualization and classification of the curves is carried out using the K-means algorithm, to finally obt... [more]

The transformation of the European energy sector is becoming a priority for the European Union. This is indicated, for instance, in the European Union strategy known as the European Green Deal. According to the Green Deal, the area of ‘research and innovation’ is one which can counteract climate change. Universities can play a significant role in this by adopting a pedagogical approach aimed at mobilizing the spirit of innovation and entrepreneurship in young professionals. In addition to modifying curricula related to mining, energy, and environmental engineering, i.e., activities in recognized, traditional schemes, one prospective tool may be the involvement of students and PhD candidates in European initiatives such as the InnoEnergy PhD School (which is funded by the European Institute of Innovation and Technology). This paper aims to discuss the InnoEnergy PhD School programme as a possible instrument for mitigating the negative effects of energy transformation. The article analyz... [more]

Polymer and surfactant (S/P) binary flooding is a widely used chemical flooding technology for enhanced oil recovery (EOR). However, it is mostly used in the five-spot well pattern, and there is little research on the effect of well patterns on its flow law and EOR efficiency in the reservoir. In this paper, the flow intensity of S/P flooding in an inverted seven-spot well unit and its EOR efficiency are investigated. Based on the theoretical derivation and simulation, the flow distribution at different positions in the inverted seven-spot well pattern unit was calculated. The oil displacement efficiency was evaluated by simulating different flow intensities with various flow velocity. The microscopic residual oil of the core at the end of displacement was scanned and recognized. The 2D model was used to simulate the well pattern to clarify the EOR of S/P flooding. The results show that the swept area in the well unit can be divided into the strong swept region (>0.2 MPa); medium swept... [more]

Recent advancements in green building technologies (GBTs) have grown substantially, as an outcome of the environmental, economic and societal benefits. It has the potential to move toward sustainable development, specifically related to climate change. In GBTs, the main objective is to use energy, water and other resources in a balanced way, without using them extensively. This will improve the environmental conditions. Green buildings (GBs) are beneficial when it comes to energy consumption and emissions; low maintenance and operation costs; boosting health and productivity; etc. There is a lack of a critical review of the past or present research work in the area of the Green Building Technology (GBT) sector to identify the future roadmap for sustainable green building technologies. A critical review, with the help of proper research methodology, was identified. The scope of this study is to analyze the existing work on different issues, and find different key issues in green buildin... [more]

The solid-state transformer is the enabling technology for the future of electric power systems. The increasing relevance of this equipment demands higher standards for efficiency and losses reduction. The dual active bridge (DAB) topology is the most usual DC-DC converter used in the solid-state transformer, and is responsible for part of its switching losses. The traditional phase-shift modulation used on DAB converters presents significant switching losses during the operation with reduced loads. The alternative Triangular and Trapezoidal Modulations have been proposed in recent literature; however, there are limitations on the maximum power these techniques can deal with. This paper presents an adaptive model predictive control to select among these three techniques, according to the converter model, the one that minimizes the switching losses and allows the current demanded by the load. Moreover, an alternative cost function is proposed, including the output voltage and current. T... [more]

Power systems worldwide are experiencing rapid evolvements with a massive increase of renewable generation in order to meet the ambitious decarbonization targets. A significant amount of renewable generation is from Distributed Energy Resources (DERs), upon which the system operators often have limited visibility. This can bring significant challenges as the increasing DERs’ can lead to network constraints being violated, presenting critical risks for network security. Enhancing the visibility of DERs can be achieved via the provision of communication links, but this can be costly, particularly for real time applications. Digital Twin (DT) is an emerging technology that is considered as a promising solution for enhancing the visibility of a physical system, where only a limited set of data is required to be transmitted with the rest data of interest can be estimated via the DT. The development and demonstration of DTs requires realistic testing and validation enviorment in order to acc... [more]

Disruptive events, such as the winter storm of 2021 that left 40 million people in the U.S. without power, have revealed the potential danger of societal dependence on centralized energy sources. Localized energy grids (called microgrids (MGs)) can help add energy reliability and independence by using distributed generators (DGs) with photovoltaic (PV) energy sources and energy storage systems (ESSs). Such MGs can independently energize critical energy demand nodes (DNs) when isolated from the primary grid with renewable energy. The optimal sizes and assignments of PVDG/ESS units to the DNs during outages are crucial to increasing energy reliability. However, finding an optimal configuration−energy management strategy is difficult due to the investment costs, complexity of assignments, potential capacities, and uncertainties in the PV system output. In this research, we developed a simulation framework, augmented by genetic algorithms (GAs), to optimize costs and fulfill energy demands... [more]

The direct release of energy from the groundwater under the building of the Sobieski Family Palace in Lublin, Poland, and the obtainment of heat and cooling energy for Heating, Ventilation, and Air Conditioning systems (HVAC) provide an opportunity to reduce electricity and heat consumption and to limit CO2 emissions by 15−50%. The upgrade to the Sobieski Family Palace and the addition of new educational and administrative functions require state-of-the-art, energy-saving, and environmentally friendly solutions such as Fuel Cells and Hydrogen for Heating, Ventilation, and Air Conditioning (FCH HVAC) systems. As part of the program “Research for high-quality air in architecture and urban studies,” carried out since 2018 at the Institute of Architecture Planning, Department of Contemporary Architecture, Faculty of Civil Engineering and Architecture of the Lublin University of Technology, in 2021, further research was carried out in order to prepare for the potential implementation in 202... [more]

Micro hydropower (MHP) provides a viable renewable energy solution from which individuals, organisations and communities can also derive social value and benefits. Desk studies and literature reviews show limited studies that (a) quantify the social impact of MHPs in water networks and (b), establish evaluation methods for such analysis. To date, most studies relating to MHP projects have focused on physical and technological parameters, as well as cost and environmental factors that influence their design, installation, operation, and maintenance. Less attention has been given to the intangible social, political, and institutional considerations, which are also important for the acceptability and adoption of renewables such as MHPs, and for their performative longevity. This study addresses these gaps. The social return on investment (SROI) method was used as the basis to quantify the cost and social returns of three MHP demonstrators in a public and private water supply, and irrigati... [more]

The real-time speed estimation of induction motors (IMs) is important for the motors’ state monitoring and control. The utilization of rotor slot harmonics (RSHs) due to the inherent cogging effect is regarded as a promising way to realize the speed estimation of IMs. The key to the RSH-based speed estimation method is how to accurately and quickly identify the frequency of an RSH signal. However, as the RSH signal always consists of two side-frequency components that are adjacent to each other, it is actually improper to directly use the conventional phase-locked loop (PLL) method designed for single-frequency tracking. Furthermore, the form of the two side components in the frequency domain also leads to a significant amplitude fluctuation in the time-domain waveform of RSHs, thus resulting in the obvious frequency tracking errors of the conventional PLL method. In this paper, we proposed an improved PLL through harmonic separation to further improve the performance of the RSH-based... [more]

With the increasing awareness of environmental protection and the support of national policy, as well as the maturing of solar power generation technology, solar power generation has become one of the most promising renewable energies. However, due to changes in external factors such as season, time, weather, cloud cover, etc., solar radiation is uncertain, and it is difficult to predict energy output, even for the next hour. This inherent instability is a particularly difficult issue for the prediction of energy output in the effective operation of solar power systems. This paper proposes a grey wolf optimization (GWO)-based general regression neural network (GRNN), which is expected to provide more accurate predictions with shorter computational times. Therefore, a self-organizing map (SOM) is utilized to realize the weather clustering and the training of the GRNN with a GWO model. The performance of the proposed model is investigated using short-term and ultra-short-term forecasting... [more]

The combustion phenomena are always complex in nature due to the involvement of complex series and parallel reactions. There are various methods that are involved in analyzing combustion phenomena. Viscosity is the first and foremost factor that acts as the DNA of fuel. By evaluating the viscosity, it is possible initially to understand the combustion phenomena. Thermophysical and transport properties are helpful during the intensification of the combustion process. Combustion experiments are economically infeasible and time-consuming processes. Combustion simulations demand excellent computational facilities with detailed knowledge of chemical kinetics. So far, the majority of researchers have focused on analyzing coal combustion phenomena, whereas less work has been carried out on liquid fuels, especially biodiesel combustion analysis. Traditional engine testing provides only performance parameters, and it fails to have oversight of the thermodynamic aspects. The application of therm... [more]

The United Arab Emirates is moving towards the use of renewable energy for many reasons, including the country’s high energy consumption, unstable oil prices, and increasing carbon dioxide emissions. The usage of electric vehicles can improve public health and reduce emissions that contribute to climate change. Thus, the usage of renewable energy resources to meet the demands of electric vehicles is the major challenge influencing the development of an optimal smart system that can satisfy energy requirements, enhance sustainability and reduce negative environmental impacts. The objective of this study was to examine different configurations of hybrid renewable energy systems for electric vehicle charging in Abu Dhabi city, UAE. A comprehensive study was conducted to investigate previous electric vehicle charging approaches and formulate the problem accordingly. Subsequently, methods for acquiring data with respect to the energy input and load profiles were determined, and a techno-eco... [more]

The performance of droplets captured by the wire mesh demister in a seawater desalination system seriously affects the quality of water desalination. Therefore, it is of great significance to study the droplet impact in the wire mesh demister to improve the demister’s efficiency. In this paper, a two-dimensional model of the droplet impacting the wire is established. The processes of the droplet impacting a flat wire and a circular wire are simulated by using the VOF model in Fluent, and a comparative analysis is conducted. The results demonstrate that both wires experience spreading and splashing stages, but when the wire is circular, the length of the lifted lamella is longer, the peak force on the wall is larger, the splash’s start time is earlier, and the number of secondary droplets is greater; the variation rule of the force on the wall caused by the change of initial velocity is similar, and the increase in initial velocity will promote the occurrence of splash phenomenon, but t... [more]

Energy Efficient Building (EEB) design decisions that have traditionally been made in the later stages of the design process now often need to be made as early as the feasibility analysis stage. However, at this very early stage, the design frame does not yet provide sufficient details for accurate simulations to be run. In addition, even if the decision-makers consider an exhaustive list of options, the selected design may not be optimal, or carefully considered decisions may later need to be rolled back. At this stage, design exploration is much more important than evaluating the performance of alternatives, thus a more transparent and interpretable design support model is more advantageous for design decision-making. In the present study, we develop an EEB design decision-support model constructed by a transparent meta-model algorithm of simulations that provides reasonable accuracy, whereas most of the literature used opaque algorithms. The conditional inference tree (CIT) algorith... [more]

Based on the characteristics of low-permeability oil and gas reservoirs and the requirements for profile control and water plugging and for water cut decrease and production increase in the high water cut stage of the middle and late exploitation periods, ultrafine temperature-resistant and salt-tolerant swellable particles DS-1 suitable for low permeability oilfields were prepared by introducing N,N-dimethylacrylamide(DMAA) monomers into the 2-acrylamido-2-methylpropanesulfonic acid (AMPS)/acrylamide(AM)/N,N-dimethylbisacrylamide ternary crosslinking system. The median of initial particle size was 22.00 μm, and is compatible with formation pore throats. A static water absorption experiment showed that the particles can still maintain a high swelling ratio after 15 days at a high temperature and high mineralization degree, so they have long-term stability. The physical and chemical properties of the particles were analyzed microscopically using the infrared spectrum method and the scan... [more]

With the rapid development of the hydrogen energy industry, the number of hydrogen cylinders has reached a very large scale. At present, both domestic and international experiences of hydrogen cylinder inspection are zero, which makes the inspection work more challenging and unpredictable. In recent years, more and more attention has been paid to the responsibility of safety in production, but the research on the risk and safety of cylinder inspection institutions is very limited. In this paper, the Job safety analysis (JSA) method is used to carry out systematic risk identification, risk assessment, risk prevention, and other research work of the cylinder inspection station. After the JSA method and experience accumulation, the management strategy is continuously perfecting, and the security risk level is absolutely decreasing.

A method has been developed for producing mixed actinide oxides suitable for fabricating mixed nitride uranium plutonium fuel for fast neutron reactors. The method is based on the use of microwave radiation for the direct denitration of actinide nitrate solutions. The possibility of producing uranium, plutonium, and neptunium-mixed oxides was shown. A pilot installation for preparing actinide oxides by microwave denitration was designed and tested. Mixed oxides of uranium and cerium (for plutonium imitation) were successfully used to synthesize uranium cerium nitrides and produce fuel pellets. Compared with the precipitation (ammonia) method of producing mixed oxides, microwave denitration reduces the generation of secondary liquid radioactive waste by more than six times.

This paper presents a model to predict the number of refuelling trips by vehicles on any given day considering weather conditions and time of the year. The predicted refuelling trips were founded on count-based data, i.e., data that contain events that occur at a certain rate. The paper presents an algorithm developed using Python programming language and the statsmodels module to achieve this. The results indicate that the GP-1 model developed in this paper is statistically significant at the 95% confidence level as it was able to converge—however, precipitation and high ambient temperature conditions are considered statistically insignificant in this model. The viability of the model was further tested on the remaining 20% of the data. Sensitivity tests indicate that there is a good correlation between the actual trips and predicted trips when 70% of the data are used to train the model. Overall, the model presented can be used to predict the number of trips taken by vehicles to refu... [more]

The behavior of convective heat transfer in an enclosure filled with Cu−water nanofluid with a baffle has been numerically studied using the finite element method. The enclosure’s top and bottom walls were adiabatic, while the other two were maintained at various temperatures. The left hot wall had an effective thickness and a baffle was added to the bottom wall. The influence of different parameters like the nanoparticle’s concentration (ϕ), Rayleigh number (Ra), the thermal conductivity ratio of the thick wall (Kr), baffle angle (Ø), and the hot wall thickness (D) on the isotherm and fluid flow patterns were examined. The result showed that the average Nusselt number was enhanced, owing to the strength of the buoyancy force becoming more effective. Furthermore, as the baffle inclination angle increased, the maximum stream function at the core corresponded to the angle when it reached Ø=60°, then it gradually decreased to the minimum value as the baffle angle reached close to Ø=120°.

It is widely accepted that carbon capture and utilization technologies are an effective way of lowering the amount of greenhouse gases released into the atmosphere. A bibliometric analysis is presented in this article to investigate the development of carbon capture and utilization. The study was conducted to identify the trends in publishing, dominant contributing authors, institutions, countries, potential publishing sources, and the most cited publications in this research area. A total of 4204 articles published between 2007 and 2021 were analyzed, covering 13,272 authors, 727 journals, and 88 countries. The findings indicate that the most productive and influential authors have British and American affiliations. The United States, the United Kingdom, and China have conducted most studies on the aforementioned topic. Imperial College London, United Kingdom, has the highest number of publications in this field of research. Furthermore, the collaborative analysis was developed by cre... [more]