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During the past two decades, a number of two-terminal switching devices have been demonstrated in the literature. They typically exhibit hysteric behavior in the current-to-voltage characteristics. These devices have often been also referred to as memristive devices. Their capacity to switch and exhibit electrical hysteresis has made them well-suited for applications such as data storage, in-memory computing, and in-sensor computing or in-memory sensing. The aim of this perspective paper is to is twofold. Firstly, it seeks to provide a comprehensive examination of the existing research findings in the field and engage in a critical discussion regarding the potential for the development of new non-Von-Neumann computing machines that can seamlessly integrate sensing and computing within memory units. Secondly, this paper aims to demonstrate the practical application of such an innovative approach in the realm of cancer medicine. Specifically, it explores the modern concept of employing multiple cancer markers simultaneously to enhance the efficiency of diagnostic processes in cancer medicine.

Droplet-based microfluidics is a modular platform in high-throughput single-cell and small sample analyses. However, this droplet microfluidic system was widely fabricated using soft lithography or glass capillaries, which is expensive and technically demanding for various applications, limiting use in resource-poor settings. Besides, the variation in droplet size is also restricted due to the limitations on the operating forces that the paper-based platform is able to withstand. Herein, we develop a fully integrated paper-based droplet microfluidic platform for conducting droplet generation and cell encapsulation in independent aqueous droplets dispersed in a carrier oil by incorporating electric fields. Through imposing an electric field, the droplet size would decrease with increasing the electric field and smaller droplets can be produced at high applied voltage. The droplet diameter can be adjusted by the ratio of inner and outer flow velocities as well as the applied electric field. We also demonstrated the proof of concept encapsulation application of our paper device by encapsulating yeast cells under an electric field. Using a simple wax printing method, carbon electrodes can be integrated on the paper. The integrated paper-based microfluidic platform can be fabricated easily and conducted outside of centralized laboratories. This microfluidic system shows great potential in drug and cell investigations by encapsulating cells in resource-limited environments., (© 2021 Wiley-VCH GmbH.)

Abstract The insulation performance of oil paper insulation is significantly affected by moisture such that monitoring moisture content is important. However, it is difficult to obtain the moisture content accurately due to its dynamic change under multi physical fields. Studying the moisture transportation in oil paper insulation under multi physical fields becomes a vital method in solving the problem. A multi physical model describing moisture migration was proposed, which considered the effects of temperature on moisture in different existing states in oil‐immersed paper (OIP). The temperature distribution formed a vapour pressure gradient to drive moisture migration and affected migration speed. Then, experiments and simulations of moisture migration were performed, which showed that the experiments were in good agreement with simulation. The results revealed that the temperature gradient caused uneven moisture distribution and the increased temperature reduced OIP moisture content. The established model could fully characterise moisture migration under temperature gradient, which provided a theoretical reference for predicting the risk of partial dampness and evaluating insulation performance.

Abstract Various dielectric response processes in the oil‐paper insulation are sensitively affected by the insulating states (ageing degrees and moisture contents). However, the existing research is still incomplete in revealing the microscopic mechanisms of various dielectric response processes in oil‐paper insulation with different insulating states. Given this issue, the genetic algorithm is first adopted to extract the Dissado–Hill (D–H) model parameters by simulating the frequency domain spectroscopy (FDS) of oil‐paper insulation. Then, the change laws of the extracted D–H model parameters are adopted to reveal the microscopic mechanisms of various dielectric response processes. Microscopic mechanisms of four dielectric response processes are studied, which are quasi‐dc relaxation, loss peak relaxation, optical frequency relaxation, and DC conductance. Meanwhile, due to the dielectric response processes being dominated by various polar particles (methanol, ethanol, furfural, and water molecule), the contents of various ageing by‐products dissolved in the insulating oil are measured to support the above analysis. In this respect, a dielectric theoretical reference for the FDS technique to research the insulating states of oil‐paper insulation is provided.

Abstract The main part of oil‐immersed power equipment is oil‐paper insulation. At lower ambient temperatures, transformer oil will become viscous. As a result, compared to those at room temperature or operating temperature, the frequency domain dielectric properties of oil‐paper insulation at low temperatures are drastically different. For evaluating the insulation condition of electrical equipment, it is essential to accurately determine their dielectric properties. This paper described the FDS test, the DC conductivity test, and the transformer oil viscosity test, which was carried out in a laboratory environment for different ageing of oil‐immersed pressboard and transformer oil at 233–373 K. The effects of temperature on the dielectric properties at the competing mechanisms of polarisation and conductivity loss were clarified based on variations of the FDS curves. Considering the viscosity change of ageing transformer oil at low temperatures, the Arrhenius and VFT viscosity equations were used to achieve a fitting calculation in the different temperature zones. Based on the molecular/ion transition model in the force field and electric field, the characterisation relationships between the dynamic viscosity, DC conductivity, and test temperature of transformer oil were established. The limitations of conventional transformer oil equivalent dielectric relaxation models over a wide temperature range were finally clarified by combining the test findings of the DC conductivity over a wide temperature range with observed and simulated calculations. This paper provides an essential theoretical reference when using the FDS test to diagnose the insulation performance of oil‐immersed power equipment in extremely cold regions.

Abstract Oil‐paper insulation material is an essential component for oil‐filled transformers, and polyimide (PI) insulation paper is a novel material in the field of electricity. The improvement of insulation class for insulation paper has gained significant attention in recent years. In this study, SiO2 nanoparticles were modified with a silane coupling agent (KH550), and the KH550‐SiO2 was added to the fibre membrane through in situ polymerisation. The chemical composition and microcosmic characteristics of the PI porous fibre membrane were characterised using FT‐IR and SEM FT‐IR and SEM. Consequently, the dielectric constant of the composite paper was reduced to 2.3 upon adding 3 wt% of KH550‐SiO2, and the dielectric strength reached its maximum value of 85 kV/mm. The results demonstrate that the insulation performance of the KH550‐SiO2/PI composite was significantly improved due to the incorporation of nano‐SiO2. This establishes an efficient approach for achieving excellent electrical and thermal properties in practical applications using the KH550‐SiO2/PI fibre membrane.

Abstract The moisture generated by the ageing of the oil‐paper insulating system can easily lead to the deterioration of the performance of the insulating paper. In order to alleviate the impact of moisture on the performance of the insulating paper, we developed a kind of lipophilic hydrophobic self‐repairing cellulose insulating paper (new insulating paper) based on the ternary system of polytetrafluoroethylene, fluorocarbon surfactant and fluorinated alkyl silane, and accelerated thermal ageing test for 45 days at 130°C was carried out. The experimental results show that the new insulating paper with excellent lipophilic property can realise hydrophobic self‐repairing through heat treatment after physical damage. The tensile strength and elongation at break of the new insulating paper increased by 5%–8% and 6.25%–27% respectively compared with the original cellulose insulating paper. At the end of ageing, the relative dielectric constant and dielectric loss factor of new insulating paper are 10.4% and 9.9% lower than that of the original cellulose insulating paper, while the breakdown voltage is 6.8% higher. The acid and moisture content produced during the ageing process of the insulating oil impregnated with new insulating paper are also less, indicating that the coating can delay the ageing of the insulating paper.

Abstract The ionic transport process is an important counterpart to charge transport in oil‐paper insulation, and it significantly impacts oil flow electrification at the oil‐paper interface. Despite this, the dynamics of this phenomenon and the underlying mechanisms remain unclear, particularly at the molecular level. To understand this fundamental aspect, we conduct Molecular Dynamics study on the transport behaviour of an impurity ion in different oil‐paper insulation models under various external electric fields. Different influence factors, such as external electric fields, temperatures, and local structural characteristics, are investigated in relation to the corresponding ionic mobility in different polymer models. According to the simulations, ionic mobility and its response to electric fields are higher in weaker electrostatic models. As a result, mineral oil exhibits the highest ionic mobility and the most substantial enhancement of ionic mobility by external electric fields, followed by vegetable oil, oil‐paper blends, and insulating paper. This significant deviation in ionic mobility between oil and paper leads to the formation of an electric double layer near the oil‐paper interface. The underlying physical mechanisms of different ionic mobility and its response to the electric field in different polymer models could be explained by the different polymer structural influences in terms of interaction energy and coordination numbers in a static manner, as well as by the interactions between the impurity ion and its surrounding atoms in terms of lifetime correlation functions and velocity autocorrelation functions in a dynamic manner. In addition, the influence of temperature on ionic mobility in mineral and vegetable oil is examined, and their activation energies are calculated. Advancing in the fundamental understanding of the dynamics of the ion transport process in oil‐paper insulation is vital to improving their insulating properties for oil‐impregnated power transformers.

Abstract Engineering experience shows that for transformers with long service life and serious moisture exposure, the inter‐turn paper insulation inside the winding will precipitate bubbles under the condition of electric field and conductor heating, which will endanger the equipment insulation. In order to explore the influence factors of bubbles formation in the moist insulating paper of transformers, based on the existing research on the influence of moisture content and gas dissolution in transformer oil, this study further considers the influence of air pressure (AP) and electric field and establishes an experimental platform to change the air pressure and electric field, thereby studying the formation characteristics of bubbles in oil‐paper insulation. The results show that air pressure and electric field can affect the initial temperature, volume, and shape of bubble formation. From 0 to −0.05 MPa for air pressure, the initial temperature of bubble generation decreased by 41°C, its maximum two‐dimensional projected area increased by 418.4% with more severe distortion, and the breakdown voltage decreased. When the AC voltage applied on the needle plate electrode increased from 0 to 10 kV, the initial temperature of bubble formation increased by 29°C, and the maximum two‐dimensional projection area increased by 336.6%.

Abstract Frequency domain dielectric spectroscopy (FDS) is an effective method reflecting the changes of ageing status of silicone oil‐immersed insulation paper. For better evaluating the ageing status of silicone oil‐immersed insulation paper, an evaluation method was studied by analysing the ageing kinetic model and results of FDS. First, the method to separate the different polarization losses and conductivity loss from the results of FDS was studied. Then, based on the idea of ageing correction translation coefficient and time‐varying pre exponential factor, the zero order ageing dynamic model was modified, which combines the ageing kinetic model with the results of FDS. Finally, the evaluation method for the degree of polymerisation (DP) of silicone oil‐immersed paper was proposed, and experiments were conducted to obtain the parameters in the modified model and then to verify the proposed method. The results show that the proposed method can be used to evaluate the DP effectively.

Abstract Furfural content in oil is considered as an effective parameter to evaluate the ageing state of oil‐immersed transformers. In previous thermal ageing experiments at 130°C, we found that moisture increment in oil‐paper system makes more furfural distribute in oil. However, the microcosmic mechanism of moisture effect on furfural diffusion from paper to oil is still unknown, and the furfural equilibrium law at transformers' typical operating temperatures is also unclear, resulting in the unreliability of the existed furfural evaluation model. To elucidate the above problems, molecular dynamics simulation and furfural equilibrium experiments at 60°C were carried out at different moisture contents. The results show that high moisture content makes part of furfural diffuse from paper to oil indeed. Supposing moisture content increases from 1% to 2%, mass fraction of furfural in oil may increase from 32.98% to 49.83%, leading to furfural content in oil increases from 0.76 mg/L to 1.06 mg/L when the degree of polymerisation of insulation paper is about 524, which increased by 39.5%. The increase in moisture content makes cellulose form hydrogen bonds with H2O preferentially, decreasing the hydrogen bonds interaction between cellulose and furfural. Thus, partial furfural falls off cellulose and diffuses into oil, leading to an increase in furfural content in oil. To eliminate the moisture interference, a corrected furfural assessment model based on the moisture equilibrium curve has been constructed, which can accurately evaluate the ageing state of insulation paper regardless of the moisture influence.

Abstract Organophilic groups of coupling agents can be the key factor for the electrical performance of Boron Nitride (BN)/meta‐aramid composite paper. In this article, four types of triethoxy‐silane coupling agents with different organophilic groups, including mercapto‐propyl (MP), glycidylether‐propyl (GP), amino‐propyl (AP) and trideca‐fluoro‐octyl (TFO) were studied. The structural and electrical properties of modified papers were compared, and the molecular simulation was conducted to reveal the interface interaction of modified BN and aramid. The results show that AP, GP and MP follow the same mechanism, improving the electrical performance by modifying the interface stability and paper structure, and the ranks of improving effects are AP, MP and GP. While, TFO mainly relies on the fluorine components to implement the electrical reinforcement, which compensates for the shortcoming in the paper structure. By choosing TFO and filler content of 15 wt%, the optimal breakdown strength of the paper can be increased to 28.17 kV/mm, 1.8 times that of the paper doped with the hydroxylated BN.

Abstract In order to improve the sensitivity and accuracy of oil‐paper insulation partial discharge detection by the fibre‐optic Fabry–Perot (FP) ultrasonic sensor, this work studied the ultrasonic signal’s frequency characteristics of typical oil‐paper insulation partial discharges and the vibration characteristics of the FP sensor’s diaphragm in the liquid environment. Based on the works above, a multifrequency FP sensor array is proposed, consisting of several FP sensors with different resonant frequencies to detect partial discharges. The experimental results show that the liquid environment has a significant effect on the vibration characteristics of the FP sensor’s diaphragm, and the sensitivity and accuracy of partial discharge detection can be improved based on the multifrequency FP sensing array, which can also be applied in the pattern recognition and localisation of partial discharges.

Abstract Cellulose insulation paper is the main component of oil‐paper insulation systems in oil‐immersed transformers. However, the poor thermal conductivity and thermal stability of the cellulose can lead to thermal ageing. It is critical to address this issue by improving the performance of cellulose, nano‐SiC‐modified cellulose models were established by molecular simulation, while nano‐SiC composite papersheets were prepared based on the simulation results, and the effects of different contents of nano‐SiC on the papersheets were investigated. Macroscopically, doping nano‐SiC particles can enhance the thermal stability of cellulose; compared with the unmodified papersheet, the thermal conductivity and tensile strength of the modified papersheets are increased by 44.3% and 42.8%, respectively. The degree of polymerisation of the modified papersheet decreased more slowly than that of the unmodified papersheet under accelerated thermal ageing, showing that the modified papersheet has better anti‐ageing properties. Microscopically, with the addition of nano‐SiC, the simulations showed that the mean square displacement of the cellulose decreases dramatically and the distribution of the free volume becomes difficult to disperse, which corresponds to the decrease in porosity in the experiments. As a result, this research provides a way for improving the thermal‐mechanical properties of cellulose that has practical application significance.

Abstract The ageing kinetic model is regarded as an effective tool to describe the degradation of transformer paper insulation. However, the temperature of the transformer winding is unevenly distributed, and the existing ageing kinetic models only depend on experimental data of accelerated thermal ageing at a constant temperature. Given this issue, this work proposes an improved second‐order kinetic model accounting for the non‐uniform thermal field. First, oil‐paper insulation samples with different ageing stages are prepared under the non‐uniform thermal field. Then, the sample's experimental data of moisture dispersion and distribution of degree of polymerisation are collected. On this basis, the improved second‐order kinetic model is derived to simulate insulating paper's ageing process subjected to an axial temperature gradient. Further, the relationship of the parameters in the improved second‐order kinetic model with the temperature and moisture content at different winding heights is obtained. Finally, the proposed model is validated, and the results show that the proposed model is more scientific than the traditional models to describe the degradation of paper insulation. In that respect, this work illustrates an improved second‐order kinetic model to provide a reference for the ageing assessment/life prediction of transformer paper insulation under the non‐uniform thermal field.

Abstract In order to elucidate mechanical impacts affecting the insulation strength of thermal‐ageing oil‐impregnated pressboards, we perform mechanical degradation experiments of impacting forces that are represented as the winding‐suffered stresses on thermal‐ageing oil‐paper insulation in transient short‐circuit of transformer. Water content, degree of polymerisation (DP), partial discharge inception voltage and AC breakdown field strength are tested and analysed for diverse thermal‐ageing levels. An analytical model of mechanical degradation is established by relating dielectric breakdown strength to mechanical impact. Mechanical impacts result in less water content in thermal‐aging oil‐impregnated pressboards while causing reduction and increment of DP, respectively, in mildly and severely aged oil‐impregnated pressboards. Partial discharge inception voltage and dielectric breakdown strength vary significantly with the numbers of impact cycles, showing a maximum value under low‐intensity impact and decreasing monotonously under high‐intensity impact. High‐intensity mechanical impacts will evidently exacerbate the thermal deterioration process of oil‐impregnated pressboards, which is primarily attributed to cellulose fibre fractures in pressboard cracks produced by equivalent tensile stress of mechanical impacts. It is acceptable for mildly aged oil‐impregnated pressboards to suffer low‐intensity mechanical impacts that will alleviate insulation degradation by restraining partial discharge in smaller oil‐gaps and prolonging breakdown discharge pathways along impact‐caused cracks.

The increasing demand for world paper consumption stimulates the growth of paper and pulp industries and lead to high carbon emission. Electricity and thermal energy are critically demanded by the paper and pulp industries. The premises utilizing grid electricity are carbon intensive as the grid energy mainly generates electricity from burning coal. Alternative energy resources that are less carbon-intensive such as natural gas and solar energy, can be used to generate electricity to fulfil the energy demand of the pulp and paper industry and mitigate carbon emissions. This study implemented cogeneration natural gas boilers and solar energy to substitute the dependency on grid electricity from Tenaga National Berhad as they are less carbon intensive than coal fuel. Carbon and economic analysis were conducted on the case studies that replaced grid electricity supply from TNB by implementing cogeneration natural gas boilers and solar energy. The results show that the total savings/kWh of energy produced from cogeneration natural gas boiler range from 0.155 MYR/kWh to 0.164 MYR/kWh. The total savings per kWh of energy produced from solar energy is higher, which was 0.207 MYR/kWh of solar energy produced. Solar has better operation cost savings per unit of electricity generated, but a limited installation area restricts the implementation. In the future, the increasing efficiency of solar technology will make the option viable while achieving more cost savings and carbon emission reduction. [ABSTRACT FROM AUTHOR]

Abstract The charge transport and accumulation in oil–paper can cause the insulation degradation. So far, the most widely used model to simulate space charge transport and accumulation is the bipolar charge transport (BCT) model, which can well simulate the space charge dynamics. However, there are two shortcomings in the algorithms for solving the BCT model. One is that there is almost no use of vectorisation technology, which may increase the complexity of the algorithm, the other is the usage of fixed step size which might bring extra computation cost. In view of this, an adaptive time‐stepping transient upstream finite element method (FEM) is developed to solve the BCT model considering trapping/detrapping, as well as the recombination phenomenon under DC condition in this article. Then, a vectorisation technology is used in the method to optimise the algorithm. Moreover, the adaptive time‐stepping method is introduced in simulation to reduce computation time and calculation amount. Simulation results are obtained by programing and later presented, which are basically consistent with the corresponding experimental results. Therefore, the proposed method is expected to promote the optimization design of the oil–paper insulation system.

Under the background of cap-and-trade mechanisms, this article constructs a game model of the electricity supply chain, which is dominated by electricity generators and followed by electricity sellers, taking into account the situation of electricity generators investing in renewable energy and energy storage under the grandfathering mechanism (GM) and benchmarking mechanism (BM). By comparing the equilibrium solutions in different cases, the research finds that (1) compared with the grandfathering mechanism, the benchmarking mechanism has more investment in renewable energy and higher energy storage quality; (2) in the consumer market, compared with GM, the electricity price and the electricity demand are higher under BM; (3) an increase in the renewable energy preference coefficient or carbon price will lead to an increase in the electricity wholesale price, renewable energy investment, energy storage quality, electricity price, and electricity demand. Further, an increase in the energy storage cost coefficient or renewable energy investment cost coefficient will result in lower electricity wholesale price, renewable energy investment, energy storage quality, electricity price, and electricity demand; and (4) the profit of the generator under GM is higher than that under BM when the total carbon quota is larger, while the profit of the generator under BM is higher than that under GM when the unit carbon quota is larger., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Attributable to the prosperous production growth of palm oil in Malaysia, the generated palm oil mill effluent (POME) poses a high threat owing to its highly polluted characteristic. Urged by the escalating concern of environmental conservation, POME pollution abatement and potential energy recovery from the effluent are flagged up as a research topic of interest. In this study, a cutting-edge photocatalytic fuel cell (PFC) system with employment of ZnO/Zn nanorod array (NRA) photoanode, CuO/Cu cathode, and persulfate (PS) oxidant was successfully designed to improve the treatment of POME and simultaneous energy production. The photoelectrodes were fabricated and characterized by field emission scanning electron microscopy with energy (FESEM), X-ray diffraction (XRD), energy-dispersive X-ray (EDX), and Brunauer, Emmett, and Teller analysis (BET). Owing to the properties of strong oxidant of PS, the proposed PFC/PS system has exhibited exceptional performance, attaining chemical oxygen demand (COD) removal efficiency of 96.2%, open circuit voltage (V oc ) of 740.0 mV, short circuit current density (J sc ) of 146.7 μA cm -2 , and power density (P max ) of 35.6 μW cm -2 . The pre-eminent PFC/PS system performance was yielded under optimal conditions of 2.5 mM of persulfate oxidant, POME dilution factor of 1:20, and natural solution pH of 8.51. Subsequently, the postulated photoelectrocatalytic POME treatment mechanism was elucidated by the radical scavenging study and Mott-Schottky (M-S) analysis. The following recycling test affirmed the stability and durability of the photoanode after four continuous repetition usages while the assessed electrical energy efficiency revealed the economic viability of PFC system serving as a post-treatment for abatement of POME. These findings contributed toward enhancing the sustainability criteria and economic viability of palm oil by adopting sustainable and efficient POME post-treatment technology., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Although, Spain does not obtain an official arctic strategy, it was mentioned in the paper for Spanish Polar Strategy that the Arctic region has become one of the country's national interests. The government of Spain is also deeply concerned about the problem of climate change and how it affects economic and social aspects of life. When addressing the Arctic energy issue we must make a prior delimitation, since it does not propose to study in detail, and only in general description, the internal functioning of the Arctic energy systems, that is, the one that serves to supply their populations with lighting, water, gas or electricity. [ABSTRACT FROM AUTHOR]

Purpose: High permittivity dielectric pads are known to be effective for tailoring the RF field and improving image quality in high field MRI. Despite a number of studies reporting benign specific absorption rate (SAR) effects, their "universal" safety remains an open concern. In this work, we evaluate the impact of the insulation material in between the pad and the body, using both RF simulations as well as phantom experiments., Methods: A 3T configuration with high permittivity material was simulated and characterized experimentally in terms of B 1 + fields and RF power absorption, both with and without electrical insulation in between the high permittivity material and the sample. Different insulation conditions were compared, and electromagnetic analyses on the induced current density were performed to elucidate the effect., Results: Increases in RF heating of up to 49% were observed experimentally in a tissue-mimicking phantom after removing the material insulation. The B 1 + magnitude and RF transceive phase were not affected. Simulations indicated that an insulation thickness of 0.5-2 mm should be accounted for in numerical models in order to ensure reliable results., Conclusion: A reliable RF safety assessment of high permittivity dielectric pads requires accounting for the insulating properties of the plastic encasing. Ignoring the electrical insulation can lead to erroneous results with substantial increases in local SAR at the interface. Conversely, the material insulation does not need to be modeled to predict the B 1 + effects during the design of the pad geometry., (© 2023 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.)

From a spatial perspective, this paper constructs a spatial Durbin model based on the adjacent weight matrix to analyze the impact of environmental regulation on the development of renewable energy in 30 provinces (autonomous regions and municipalities directly under the Central Government) in China from 2007 to 2020. The results show that (1) both environmental regulation and renewable energy development have positive spatial autocorrelation and form relatively similar spatial agglomeration areas, specifically showing the characteristics of "high-high" agglomeration in resource-rich areas and "low-low" agglomeration in resource-scarce areas. (2) Environmental regulation significantly promotes the development of local renewable energy and has a significant spatial spillover effect on the development of renewable energy in neighboring provinces. (3) The moderating effect results show that renewable energy installed capacity and electricity demand play an inverse moderating role between environmental regulation and renewable energy development. (4) From the perspective of different regions, the impact of environmental regulation on the development of renewable energy is heterogeneous. Based on the research conclusions, this paper finally provides corresponding policy suggestions from three aspects: regional cooperation, technical support, and differentiation., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Large-scale wind power integration has raised concerns about the reliability and stability of power systems. The rotor circuit of a doubly fed induction generator (DFIG) is highly vulnerable to unexpected voltage dips, which can cause considerable electromotive force in the circuit. Consequently, the DFIG must fulfil the fault-ride through (FRT) criteria to ensure the system's performance and contribute to voltage regulation during severe grid outages. This paper provides a hybrid solution for DFIG wind turbines with FRT capabilities, using both a modified switch-type fault current limiter (MSFTCL) and a direct current (DC) chopper. The proposed system has the merit of keeping the rotor current and the DC-link voltage within the permissible limits, enhancing the FRT capability of generators. Moreover, the boundness of supply voltage into its reference value ensures dynamic stability during symmetric and asymmetric grid failures. Further, electromagnetic torque variations are significantly reduced during fault events. Finally, the performance validation of the proposed scheme is performed in a simulation setup, and the results are compared with the existing sliding mode control (SMC) and proportional-integral (PI) controller-based approaches. The comparison results show that a hybrid strategy with advanced controllers provides superior performance for all critical parameters.

Bangladesh government is in the final stage of setting up one nuclear power plant with two units at Rooppur, Ishwardi, each having 1200 MW capacity, to be launched in 2023 to meet the energy shortage urgently. The financial cost of the project is the US $12.65 billion. The primary purpose of this paper is to calculate the economic cost of setting up this plant by using the estimation method developed by Du and Parsons (2009), MIT (2003; 2009; 2018), and Singh et al.  (2018). It has been found that the economic cost is amounted to 9.36 cents/kWh for the capacity of 2400 MW. In contrast, for a similar plant in Kudankulam, Tamil Nadu, India, the corresponding cost figure is 5.36 cents/kWh for 2000 MW. Even though it seems costlier than India, the study suggests that policymakers should prefer nuclear power, as it is cost-competitive, considering the production cost of other electricity facilities. The main advantage of nuclear power is cost-competitive baseload power generation with zero carbon emission. This nuclear power plant (NPP) project is expected to boost the energy sector of Bangladesh by transforming the country from an energy deficit country into an energy surplus country., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

As modern society becomes ever more dependent on the availability of electric power, the costs that could arise from individual and social vulnerability to large outages of long duration (LLD-outages) increases. During such an outage, even a small amount of power would be very valuable. This article compares individual and collective strategies for providing limited amounts of electric power to residential customers in a hypothetical New England community during a large electric power outage of long duration. We develop estimates of the emergency load required for survival and assess the cost of strategies to address outages that last 5, 10, and 20 days in either winter or summer. We find that the cost of collective solutions could be as much as 10 to 40 times less than individual solutions (less than $2 per month per home). However, collective solutions would require community-wide coordination, and if local distribution system lines are destroyed, only individual back-up systems could provide contingency power until those lines are repaired. Costs might be reduced if more robust distributed generation were employed that could be operated continuously with the ability to sell power back to the grid. Our cost-effectiveness analysis only assesses what could be done, developing estimates of preparedness cost. A decision about what should be done would require additional input from a range of stakeholders as well as some form of analytical deliberative process., (© 2021 Society for Risk Analysis.)

In this paper, a systematic literature review is presented, through a survey of the main digital databases, regarding modelling methods for Short-Term Load Forecasting (STLF) for hourly electricity demand for residential electricity and to realize the performance evolution and impact of Artificial Intelligence (AI) in STLF. With these specific objectives, a conceptual framework on the subject was developed, along with a systematic review of the literature based on scientific publications with high impact and a bibliometric study directed towards the scientific production of AI and STLF. The review of research articles over a 10-year period, which took place between 2012 and 2022, used the Preferred Reporting Items for Systematic and Meta-Analyses (PRISMA) method. This research resulted in more than 300 articles, available in four databases: Web of Science, IEEE Xplore, Scopus, and Science Direct. The research was organized around three central themes, which were defined through the following keywords: STLF, Electricity, and Residential, along with their corresponding synonyms. In total, 334 research articles were analyzed, and the year of publication, journal, author, geography by continent and country, and the area of application were identified. Of the 335 documents found in the initial research and after applying the inclusion/exclusion criteria, which allowed delimiting the subject addressed in the topics of interest for analysis, 38 (thirty-eight) documents were in English (26 journal articles and 12 conference papers). The results point to a diversity of modelling techniques and associated algorithms. The corresponding performance was measured with different metrics and, therefore, cannot be compared directly. Hence, it is desirable to have a unified dataset, together with a set of benchmarks with well-defined metrics for a clear comparison of all the modelling techniques and the corresponding algorithms. [ABSTRACT FROM AUTHOR]

Since the discovery that applying electrical stimulation can promote cell growth, proliferation, and tissue regeneration, research on bio-piezoelectric materials is being actively conducted. In this study, a composite material was prepared by mixing polyvinylidene fluoride (PVDF), a conventional piezoelectric polymer, and silk fibroin (SF), a natural piezoelectric material that recently attracting attention. These two polymers were fabricated into a composite fiber mat using electrospinning technology. To find optimal conditions, SF was added in various ratios to prepare electrospun PVDF/SF mats. The characteristics of these PVDF/SF composite mats were then analyzed through various evaluations and in vitro studies. It was confirmed that PVDF and SF were successfully mixed through scanning electron microscope images and structural analysis such as x-ray diffractometer and Fourier transform infrared. The results revealed that adding an appropriate amount of SF could improve the tensile strength, enhance cell proliferation rate, and generate a voltage similar to that of a conventional PVDF-only electrospinning mat. Such fabricated electrospun PVDF/SF composite mats are expected to be useful in the bio-piezoelectric field because they can maintain piezoelectricity while compensating for the shortcomings, such as low physical properties, of a PVDF electrospun mat., (© 2021 John Wiley & Sons Ltd.)

Because nanomaterials are highly reactive and electronically sensitive towards a variety of drug molecules, they are thought of as efficient drug sensors. In the present research study, an aluminum carbide (C 3 Al) monolayer is employed and its interaction is examined with cyclophosphamide (CP) by performing DFT computations. The C 3 Al monolayer is highly reactive and sensitive towards CP according to the computations. CP interacts with the C 3 Al monolayer with the adsorption energy of -31.39 kcal/mol. A considerable charge transfer (CT) indicates an enhancement in the conductivity. Also, the charge density is explained based on the electron density differences (EDD). The decrease in CP/C 3 Al energy gap (E g ) by approximately 52.91% is due to the remarkable effect of adsorption on the LUMO and the HOMO levels. Therefore, due to the decrease in E g which can generate an electrical signal, the electrical conductivity is considerably increased. These results suggest that the C 3 Al monolayer can be employed as a proper electronic drug sensor for CP. Also, the recovery time for the desorption process of CP form the surface of C 3 Al is 351 s at 598 K., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The rapid urbanization and industrialization of India have caused a demand-supply gap in the electrical sector, leading to higher electric bills. Lower-income households face the worst energy poverty in the country. Sustainable strategies like corporate social responsibility are the most effective way to combat the energy crisis. This study aims to assess the contribution of corporate social responsibility (CSR) to energy poverty alleviation (EPA) by developing the role of mediating variables such as assessment of renewable energy resource (RER), feasibility of sustainable energy supply (SES), and sustainable energy development (SED). We used hybrid research methodology such as partial least squares structural equation modeling (PLS-SEM) to analyze the collected data from professionals, economic experts, and directors in the country in 2022. The study proved that CSR directly affects energy poverty alleviation. Besides, the findings suggest RER, SES, and SED significantly lead the energy poverty alleviation. The findings of this study will divert the attention of policymakers, stakeholders, and economists toward the corporate social responsibility to mitigate the energy crisis in Indian context. A mediating role of a renewable energy resource (RER) as a value-added contribution to this study can be strengthened more in future research. Based on the results, the study illustrates that CSR acts as a catalyst to alleviate energy poverty., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Graphite, an allotrope of carbon, is also a moderately good conductor of electricity. The shading pencil lead consists of graphite mixed with clay and, therefore, can conduct electricity, allowing one to construct and demonstrate different properties and the underlying concepts of circuit elements. The grade displayed on the pencil relates to the graphite-to-clay ratio, with higher B grades indicating a higher graphite-to-clay ratio. In this paper, the main objective is to show the dependence of resistance and capacitors on different physical parameters and to calculate the value of π electrically. The materials used in this activity are readily available, affordable, and suitable for demonstration purposes. The materials used to perform these activities are shading pencils of different grades, A-4 size papers, crocodile clips, and an LCR meter. [ABSTRACT FROM AUTHOR]

Water is the most fundamental need for better yield in agriculture. Worldwide, diesel and electricity are typically used to pump water which contributes to atmospheric pollution. Besides, a power outage affects the irrigation process badly. Without water, the crop may wither away, causing a substantial economic loss. This paper discusses the resilience of a solar PV system during a power outage. HOMER Pro software was used to perform the techno-economic analysis of solar-based irrigation for four major divisions of Bangladesh, while 1-hour power outage was assigned in REopt lite to model the survivability of the system against the grid outage. The simulation outcomes showed that the energy cost is $0.1496/kWh, $0.1502/kWh, $0.1557/kWh, and $0.1576/kWh for Rajshahi, Sylhet, Dhaka, and Chattogram, respectively. About 45% of excess electricity can be stored after fulfilling all requirements. The system is more economical than a microgrid-based water pumping system and a diesel-based system, and the photovoltaic system is technically and economically suitable to pump water if the nearest grid connection is impossible. When connected to the main utility grid, the system can survive without grid power for several hours, subject to daytime outages., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

With the development of green logistics and the promotion of new energy vehicle development policies domestically and abroad, electric vehicles have been put into logistics and distribution as an alternative to traditional fuel vehicles. The Electric Vehicle Routing Problem (EVRP) has attracted widespread attention from the academic community. This paper comprehensively examines the latest research progress on electric vehicle routing models and solution algorithms in logistics and distribution. Firstly briefly introduces EVRP models considering battery losses; secondly, based on the composition of the EVRP objective function and constraints, EVRP models are classified into four types: EVRP considering load and battery life constraints, EVRP with a time window and considering charging strategies, the study of vehicle routing problems for hybrid fleets, and EVRP combined with charging/swapping station location. Then, briefly introduce exact algorithms, traditional heuristics, meta-heuristics, and hybrid algorithms for solving EVRP models. Moreover, it analyzes the main meta-heuristics that are more widely used. Finally, this review points out the development trend of EVRP theoretical methods., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)