The study introduces eco-friendly leaching agents as alternatives to traditional rare earth element(REE)extraction solvents,addressing environmental concerns associated with ammonium sulfate.Bio-based ionic liquids(IL...The study introduces eco-friendly leaching agents as alternatives to traditional rare earth element(REE)extraction solvents,addressing environmental concerns associated with ammonium sulfate.Bio-based ionic liquids(ILs),known for their non-toxic and biodegradable properties,were screened using the COSMO-RS software.Initially,105 ILs involving 7 cations and 15 anions were computationally screened to find the best ILs for REE extraction.The chosen criteria were based on hydrogen bond formation,affinity screening,hydrophobicity,viscosity,and eco-toxicity test.Based on the COSMO-RS screening,choline oleate,choline decanoate,and choline hexanoate exhibit high solubility for REEs,with a chemical potential of 17.60,17.01,and 18.37 kcal/mol at REE oxidation state+2.Choline glycinate,choline oleate,choline decanoate,choline hexanoate,choline lysinate,and choline leucinate were selected for their strong affinity to extract REE dissociate ions.Experimental results show slightly higher REE extraction from ammonium sulfate(3.17 ppm)compared to choline glycinate(3.15 ppm).For long-term applications,choline glycinate offers a promising eco-friendly and cost-effective alternative to traditional leaching agents,promoting economic feasibility and environmental friendliness.展开更多
Carbon capture and storage(CCS)remains one of the most feasible techniques for the control of Greenhouse gas emission levels.However,there will always be risks attached to the subsurface injection of CO_(2).These coul...Carbon capture and storage(CCS)remains one of the most feasible techniques for the control of Greenhouse gas emission levels.However,there will always be risks attached to the subsurface injection of CO_(2).These could be in the form of leakages from the injection wellbore due to completion failure;escape of the injected CO_(2)to neighboring aquifers due to the heterogeneous or fractured nature of the storage site;or seepage at the surface due to inadequacy of the sealing cap rock.While all these may occur,the most cost-effective and timely way to reduce the risk of leakages is by plugging the pathways.This is done using either traditional Cementous materials or more augmented sealants like organic gels and resins.A lot of studies in the literature have described this collection of materials within the context of CO_(2)conformance control.So also,there are reviews on the classification and description of these chemicals.This review provides a more systemic evaluation of these classes of chemicals.This is by providing critical analyses of how external factors like CO_(2),pH,brine salinity and hardness,rock mineralogy,pressure,temperature,and injectivity could affect the performance of different sealants that can be utilized.Based on these assessments,best practices for the application of the sealants,both at the testing stage in the laboratory and the pilot stage and field deployment,are suggested.展开更多
Geological CO_(2) storage is a promising strategy for reducing greenhouse gas emissions;however,its underlying multiphase reactive flow mechanisms remain poorly understood.We conducted steady-state imbibition relative...Geological CO_(2) storage is a promising strategy for reducing greenhouse gas emissions;however,its underlying multiphase reactive flow mechanisms remain poorly understood.We conducted steady-state imbibition relative permeability experiments on sandstone from a proposed storage site,comple-mented by in situ X-ray imaging and ex situ analyses using scanning electron microscopy(SEM)and energy-dispersive X-ray spectroscopy(EDS).Despite our use of a brine that was pre-equilibrated with CO_(2),there was a significant reduction in both CO_(2) relative permeability and absolute permeability during multiphase flow due to chemical reactions.This reduction was driven by decreased pore and throat sizes,diminished connectivity,and increased irregularity of pore and throat shapes,as revealed by in situ pore-scale imaging.Mineral dissolution,primarily of feldspar,albite,and calcite,along with precipitation resulting from feldspar-to-kaolinite transformation and fines migration,were identified as contributing factors through SEM-EDS analysis.This work provides a benchmark for storage in mineralogically complex sandstones,for which the impact of chemical reactions on multiphase flow properties has been measured.展开更多
A full-scale research study was conducted during the bored tunnelling of the Klang Valley Mass Rapid Transit-Putrajaya Line beneath an existing building structure in Kuala Lumpur,Malaysia.The primary objective was to ...A full-scale research study was conducted during the bored tunnelling of the Klang Valley Mass Rapid Transit-Putrajaya Line beneath an existing building structure in Kuala Lumpur,Malaysia.The primary objective was to investigate the tunnel-soil-pile interaction at various stages of tunnel excavation.This study combined field measurements and three-dimensional(3D)numerical analysis to understand the transient effects of TBM tunnelling on a loaded pile.An experimental pile was instrumented with vibrating wire strain gauges,an inclinometer,and distributed fibre optic sensors using Brillouin optical time domain analysis.The pile was pre-loaded and continuously monitored in real-time throughout the tunnel construction process.The 3D finite element modelling was used to simulate the pile’s transient responses based on actual tunnel boring machine(TBM)driving data.The study revealed that the zone of influence due to tunnelling effects extended from y¼2D to y¼4D,with the peak effect observed at y¼1D to 1.5D,where D represents the tunnel diameter.The analysis of axial load patterns highlighted transient responses,including tensile loads below the tunnel invert,which propagated upward and subsided due to negative skin friction.The maximum downdrag load observed reached 56%e71%of the pile’s working load.Additionally,pile movement patterns indicated outward deflections as the TBM approached and a return toward the tunnel post-passage,aligning with the predicted behaviour in a negative face loss scenario.This validated numerical framework provides a solid foundation for further parametric studies and enhances the understanding of tunnel-soil-pile interactions.展开更多
Polymeric materials have emerged as a promising alternative to electrolytic solutions in energy storage applications.However,high crystallinity and poor ionic conductivity are the main barriers restricting their daily...Polymeric materials have emerged as a promising alternative to electrolytic solutions in energy storage applications.However,high crystallinity and poor ionic conductivity are the main barriers restricting their daily application.In this study,we propose a polymer electrolyte system consisting of methylcellulose-polyvinyl alcohol(MC-PVA)blend as host material and lithium trifluoromethanesulfonate(LiCF_(3)SO_(3))as dopant,which was prepared using the solution-casting method.The electrochemical impedance spectroscopy(EIS)analysis revealed a maximum conductivity of 5.42×10^(−6) S cm^(−1) with 40 wt.%LiCF_(3)SO_(3).The key findings demonstrated that the variation in the dielectric loss(εi)and dielectric constant(εr)was significantly correlated with the variation in ionic conductivity.Fourier-transform infrared spectroscopy(FTIR)analysis was done to analyse the salt-polymer interaction by observing the shifting of selected bands.By deconvoluting FTIR spectra in the wavenumber range of 970–1100 cm^(−1),transport properties of electrolytes were investigated and found to be improved when the salt concentration was increased to 40 wt.%.Results from the X-ray diffraction(XRD)study suggested that the higher salt concentration promoted the formation of an amorphous phase,which is favourable for ionic conduction.Field emission scanning electron microscopy(FESEM)study demonstrated that the addition of salt altered the surface morphology of MC-PVA.展开更多
Unmanned aerial vehicles(UAVs)technology is rapidly advancing,offering innovative solutions for various industries,including the critical task of oil and gas pipeline surveillance.However,the limited flight time of co...Unmanned aerial vehicles(UAVs)technology is rapidly advancing,offering innovative solutions for various industries,including the critical task of oil and gas pipeline surveillance.However,the limited flight time of conventional UAVs presents a significant challenge to comprehensive and continuous monitoring,which is crucial for maintaining the integrity of pipeline infrastructure.This review paper evaluates methods for extending UAV flight endurance,focusing on their potential application in pipeline inspection.Through an extensive literature review,this study identifies the latest advancements in UAV technology,evaluates their effectiveness,and highlights the existing gaps in achieving prolonged flight operations.Advanced techniques,including artificial intelligence(AI),machine learning(ML),and deep learning(DL),are reviewed for their roles in pipeline monitoring.Notably,DL algorithms like You Only Look Once(YOLO)are explored for autonomous flight in UAV-based inspections,real-time defect detection,such as cracks,corrosion,and leaks,enhancing reliability and accuracy.A vital aspect of this research is the proposed deployment of a hybrid drone design combining lighter-than-air(LTA)and heavier-than-air(HTA)principles,achieving a balance of endurance and maneuverability.LTA vehicles utilize buoyancy to reduce energy consumption,thereby extending flight durations.The paper details the methodology for designing LTA vehicles,presenting an analysis of design parameters that align with the requirements for effective pipeline surveillance.The ongoing work is currently at Technology Readiness Level(TRL)4,where key components have been validated in laboratory conditions,with fabrication and flight testing planned for the next phase.Initial design analysis indicates that LTA configurations could offer significant advantages in flight endurance compared to traditional UAV designs.These findings lay the groundwork for future fabrication and testing phases,which will be critical in validating and assessing the proposed approach’s real-world applicability.By outlining the technical complexities and proposing specialized techniques tailored for pipeline monitoring,this paper provides a foundational framework for advancing UAV capabilities in the oil and gas sector.Researchers and industry practitioners can use this roadmap to further develop UAV-enabled surveillance solutions,aiming to improve the reliability,efficiency,and safety of pipeline monitoring.展开更多
Enhanced oil recovery(EOR)refers to themanymethodologies used to augment the volume of crude oil extracted froman oil reservoir.These approaches are used subsequent to the exhaustion of basic and secondary recovery me...Enhanced oil recovery(EOR)refers to themanymethodologies used to augment the volume of crude oil extracted froman oil reservoir.These approaches are used subsequent to the exhaustion of basic and secondary recovery methods.There are three primary categories of Enhanced Oil Recovery(EOR):thermal,gas injection,and chemical.Enhanced oil recovery methods may be costly and intricate;yet,they facilitate the extraction of supplementary oil that would otherwise remain in the reservoir.Enhanced Oil Recovery(EOR)may prolong the lifespan of an oil field and augment the total output from a specific field.The parameters influencing oil recovery are a significant problem in Enhanced Oil Recovery(EOR)systems,necessitating further examination of the components that impact them.This research examined the impact of permeability fluctuations on fluid dynamics inside a sandstone reservoir and presented a contemporary overview of the three phases of Enhanced Oil Recovery(EOR),including detailed explanations of the methodologies used and the processes facilitating oil recovery.The challenges faced with several common EOR mechanisms were identified,and solutions were suggested.Additionally,the modern trend of incorporating nanotechnology and its synergistic impacts on the stability and efficacy of conventional chemicals for enhanced oil recovery(EOR)was scrutinised and evaluated.Ultimately,laboratory results and field activities were examined.The study looked closely at hownanoparticlesmove through reservoirs and evaluated enhanced oil recovery(EOR),mobility ratio,and fluid displacement efficiency.This study offers comprehensive insights into the use of enhanced oil recovery techniques for sustainable energy generation.展开更多
Atrium spaces,common in modern construction,provide significant fire safety challenges due to their large vertical openings,which facilitate rapid smoke spread and reduce sprinkler effectiveness.Traditional smoke mana...Atrium spaces,common in modern construction,provide significant fire safety challenges due to their large vertical openings,which facilitate rapid smoke spread and reduce sprinkler effectiveness.Traditional smoke management systems primarily rely on make-up air to replace the air expelled through vents.Inadequate calibration,particularly with air velocity,can worsen fire conditions by enhancing oxygen supply,increasing soot production,and reducing visibility,so endangering safe evacuation.This study investigates the impact of make-up air velocity on smoke behaviour in atrium environments through 24 simulations performed using the FireDynamics Simulator(FDS).Scenarios include various fire intensities(1,3,5 MW)and make-up air velocities(1–3.5 m/s),with fire sources located at the centre,northeast,and southwest corners.The simulation model was validated using updated full-scale fire test data with polystyrene fuel,leading to heightened soot density and reduced smoke clear height.This Research design diverges from other studies that predominantly utilized propane pool fires and concentrated on axisymmetric(Fire at the center of the atrum),Northeast and Southeast corners of the atrium scenarios by using polystyrene-a widely accessible construction material and examining several asymetric fire sites,so providing a more authentic depiction of atrium fire settings.Research reveals that increased air velocities,especially when directed at the fire,result in greater soot density and reduced smoke clearance due to intensified combustion.The northeastern region consistently displayed high temperature readings,highlighting the importance of fire source positioning in smoke behaviour.The study recommends limiting make-up air velocity to 1 m/s to avert turbulence and guarantee safety.This research provides critical insights for fire safety design and aligns with the United Nations Sustainable Development Goals,namely SDG 9 and SDG 11,by promoting safer and more resilient construction practices in urban environments.展开更多
This study presents a detailed comparative analysis of three electron transport layer(ETL)materials for perovskite solar cells(PSCs),namely titanium dioxide(TiO_(2)),barium titanate(BaTiO_(3)or BTO),and strontium-dope...This study presents a detailed comparative analysis of three electron transport layer(ETL)materials for perovskite solar cells(PSCs),namely titanium dioxide(TiO_(2)),barium titanate(BaTiO_(3)or BTO),and strontium-doped barium titan-ate(Ba_(1−x)Sr_(x)TiO_(3)or BST),and their impact on the quantum efficiency(QE)and power conversion efficiency(PCE)of CH_(3)NH_(3)PbI_(3)(MAPbI_(3))PSCs.The optimized structure demonstrates that devices utilizing BST as an ETL achieved the highest PCE of 29.85%,exhibiting superior thermal stability with the lowest temperature coefficient of−0.43%/K.This temperature-induced degradation is comparable to that of commercially available silicon cells.Furthermore,BST-based ETLs show 29.50%and 26.48%higher PCE than those of TiO_(2)-based and BTO-based ETLs.The enhanced internal QE and favorable current density–voltage(J–V)characteristics of BST compared with those of TiO_(2)and BTO are attributed to its improved charge carrier separation,reduced recombination rates,and robust electrical characteristics under varied environmental conditions.Furthermore,the electric field and generation rate of the BST-based ETLs show a more favorable distribution than those of the TiO_(2)-based and BTO-based ETLs.These findings provide significant insights into the role of different ETLs in enhancing QE,indicating that BST is a superior ETL that enhances both the efficiency and stability of PSCs.This study contributes to the understanding of how perovskite-structured ETLs can be used to design and optimize highly efficient and stable photovoltaic devices.展开更多
The importance of organic geochemistry and basin modeling is widely recognized and used to understand the source rock potential and hydrocarbon generation history of the Mangahewa Formation,and thereby given the found...The importance of organic geochemistry and basin modeling is widely recognized and used to understand the source rock potential and hydrocarbon generation history of the Mangahewa Formation,and thereby given the foundational role in the petroleum exploration.This study utilized the total organic carbon(TOC)content and hydrogen index(HI)to investigate the dominant kerogen type and hydrogen richness for the significance of petroleum generative potential.The Mangahewa coals and carbonaceous shales exhibit an excellent source rocks,with high total organic content(TOC)of more than 22%.The coals and carbonaceous shales were also characterised by Type Ⅱ‒Ⅲ kerogen with Type Ⅲ kerogen,promising oiland gas-prones.The Mangahewa Formation reached the main oil generation,with vitrinite reflectances between 0.53%and 1.01%.Vitrinite reflectance was also used in developing themal models and reveal the transformation(TR)of 10‒50%kerogen to oil during the Late Miocene.The models also showed that the Mangahewa source rock has a significant oil generation and little expulsion competency,with a TR of up to 54%.These findings support the substantial oil-generating potential in the Taranaki Basin's southern graben and can be used as a guide when developing strategies for an oil exploration program.展开更多
Cyberbullying on social media poses significant psychological risks,yet most detection systems over-simplify the task by focusing on binary classification,ignoring nuanced categories like passive-aggressive remarks or...Cyberbullying on social media poses significant psychological risks,yet most detection systems over-simplify the task by focusing on binary classification,ignoring nuanced categories like passive-aggressive remarks or indirect slurs.To address this gap,we propose a hybrid framework combining Term Frequency-Inverse Document Frequency(TF-IDF),word-to-vector(Word2Vec),and Bidirectional Encoder Representations from Transformers(BERT)based models for multi-class cyberbullying detection.Our approach integrates TF-IDF for lexical specificity and Word2Vec for semantic relationships,fused with BERT’s contextual embeddings to capture syntactic and semantic complexities.We evaluate the framework on a publicly available dataset of 47,000 annotated social media posts across five cyberbullying categories:age,ethnicity,gender,religion,and indirect aggression.Among BERT variants tested,BERT Base Un-Cased achieved the highest performance with 93%accuracy(standard deviation across±1%5-fold cross-validation)and an average AUC of 0.96,outperforming standalone TF-IDF(78%)and Word2Vec(82%)models.Notably,it achieved near-perfect AUC scores(0.99)for age and ethnicity-based bullying.A comparative analysis with state-of-the-art benchmarks,including Generative Pre-trained Transformer 2(GPT-2)and Text-to-Text Transfer Transformer(T5)models highlights BERT’s superiority in handling ambiguous language.This work advances cyberbullying detection by demonstrating how hybrid feature extraction and transformer models improve multi-class classification,offering a scalable solution for moderating nuanced harmful content.展开更多
Energy efficiency stands as an essential factor when implementing deep reinforcement learning(DRL)policies for robotic control systems.Standard algorithms,including Deep Deterministic Policy Gradient(DDPG),primarily o...Energy efficiency stands as an essential factor when implementing deep reinforcement learning(DRL)policies for robotic control systems.Standard algorithms,including Deep Deterministic Policy Gradient(DDPG),primarily optimize task rewards but at the cost of excessively high energy consumption,making them impractical for real-world robotic systems.To address this limitation,we propose Physics-Informed DDPG(PI-DDPG),which integrates physics-based energy penalties to develop energy-efficient yet high-performing control policies.The proposed method introduces adaptive physics-informed constraints through a dynamic weighting factor(λ),enabling policies that balance reward maximization with energy savings.Our motivation is to overcome the impracticality of rewardonly optimization by designing controllers that achieve competitive performance while substantially reducing energy consumption.PI-DDPG was evaluated in nine MuJoCo continuous control environments,where it demonstrated significant improvements in energy efficiency without compromising stability or performance.Experimental results confirm that PI-DDPG substantially reduces energy consumption compared to standard DDPG,while maintaining competitive task performance.For instance,energy costs decreased from 5542.98 to 3119.02 in HalfCheetah-v4 and from1909.13 to 1586.75 in Ant-v4,with stable performance in Hopper-v4(205.95 vs.130.82)and InvertedPendulum-v4(322.97 vs.311.29).Although DDPG sometimes yields higher rewards,such as in HalfCheetah-v4(5695.37 vs.4894.59),it requires significantly greater energy expenditure.These results highlight PI-DDPG as a promising energy-conscious alternative for robotic control.展开更多
Integrating the photovoltaic/thermal(PV/T)system in green hydrogen production is an improvement in sustainable energy technologies.In PV/T systems,solar energy is converted into electricity and thermal energy simultan...Integrating the photovoltaic/thermal(PV/T)system in green hydrogen production is an improvement in sustainable energy technologies.In PV/T systems,solar energy is converted into electricity and thermal energy simultaneously using hot water or air together with electricity.This dual use saves a significant amount of energy and officially fights greenhouse gases.Different cooling techniques have been proposed in the literature for improving the overall performance of the PV/T systems;employing different types of agents including nanofluids and phase change materials.Hydrogen is the lightest and most abundant element in the universe and has later turned into a flexible energy carrier for transportation and other industrial applications.Issues,including the processes of Hydrogen manufacturing,preservation as well as some risks act as barriers.This paper provides an analysis of several recent publications on the efficiency of using PV/T technology in the process of green hydrogen production and indicates the potential for its increased efficiency as compared to conventional systems that rely on fossil fuels.Due to the effective integration of solar energy,the PV/T system can play an important role in the reduction of the levelized cost of hydrogen(LCOH)and hence play an important part in reducing the economic calculations of the decarbonized energy system.展开更多
Photocatalysis is a crucial technique for environmental cleanup and renewable energy generation.Polymer-based photocatalysts have attracted interest due to their adaptability,adjustable chemical characteristics,and en...Photocatalysis is a crucial technique for environmental cleanup and renewable energy generation.Polymer-based photocatalysts have attracted interest due to their adaptability,adjustable chemical characteristics,and enhanced light absorption efficiency.Unlike traditional inorganic photocatalysts,we can optimize polymeric systems to enhance photocatalytic efficiency and yield significant advantages in environmental remediation and energy conversion applications.This study talks about the latest developments in polymer-based photocatalysts and how important they are for cleaning water,breaking down pollutants,and making renewable energy through processes like hydrogen production and CO_(2) reduction.These materials are proficient in degrading harmful pollutants such as organic colours,insecticides,and medications,transforming them into innocuous byproducts.Moreover,its use in solar-driven water splitting for hydrogen production and CO_(2) reduction provides a sustainable solution to global energy and environmental issues.These photocatalysts are much more effective and last longer thanks to progress in polymer chemistry,nano-structuring,and hybridization with materials like semiconductors and metal nanoparticles.The research underscores the promise of polymer photocatalysts for extensive environmental applications due to their cost-efficiency,ease of separation,and reusability.Future research endeavors seek to optimize polymeric photocatalyst systems for improved stability and performance,hence advancing sustainable solutions for critical environmental and energy challenges.展开更多
The asphalt pavement industry is transforming because of the growing influence of artificial intelligence and industrial digitization.As a result of this shift,there is a stronger emphasis on advanced statistical appr...The asphalt pavement industry is transforming because of the growing influence of artificial intelligence and industrial digitization.As a result of this shift,there is a stronger emphasis on advanced statistical approaches like optimization tools like response surface methodology(RSM)and machine learning(ML)techniques.The goal of this paper is to provide a scientometric and systematic review of the application of RSM and ML applications in data-driven approaches such as optimizing,modeling,and predicting asphalt pavement performance to achieve sustainable asphalt pavements in support of numerous sustainable development goals(SDGs).These include Goals 9(sustainable infrastructure),11(urban resilience),12(sustainable construction strategies),13(climate action through optimized materials),and 17(multidisciplinary interaction).A thorough search of the ScienceDirect,Web of Science,and Scopus databases from 2010 to 2023 yielded 1249 relevant records,with 125 studies closely examined.Over the last thirteen years,there has been significant research growth in RSM and ML applications,particularly in ML-based pavement optimization.The study shows that the topic has a global presence,with notable contributions from Asia,North America,Europe,and other continents.Researchers have concentrated on utilizing sophisticated ML models such as support vector machines(SVM),artificial neural networks(ANN),and Bayesian networks for prediction.Also,the integration of RSM and ML provides a faster and more efficient method for analyzing large datasets to optimize asphalt pavement performance variables.Key contributors include the United States,China,and Malaysia,with global efforts focused on sustainable materials and approaches to reduce impact on the environment.Furthermore,the review demonstrates the integrated use of RSM and ML as transformative tools for improving sustainability,which contributes significantly to SDGs 9,11,12,13,and 17.Providing valuable insights for future research and guiding decision-making for soft computing applications for asphalt pavement projects.展开更多
This research extends the literature on the environmental Phillips curve(EPC)and environmental Kuznets curve(EKC)by focusing on the 38 member economies of the Organization for Economic Co-operation and Development(OEC...This research extends the literature on the environmental Phillips curve(EPC)and environmental Kuznets curve(EKC)by focusing on the 38 member economies of the Organization for Economic Co-operation and Development(OECD).Using panel data from 2000 to 2021,the study employs several econometric techniques,including fixed effects,feasible generalized least squares,two-stage least squares,and the generalized method of moments.Our primary findings reveal that unemployment has a significant negative impact on CO_(2)emissions,thereby supporting the validity of the EPC hypothesis within OECD countries.This suggests a trade-off between unemployment and reductions in CO_(2)emissions.Similarly,the results validate the EKC hypothesis,with further analysis indicating that the EKC exhibits an N-shaped curve-an important contribution to the literature on environmental dynamics in advanced economies.Additionally,the results show that both trade openness and renewable energy usage have significantly improved environmental quality in OECD economies.Finally,extensive causality testing identifies both one-way and two-way causal relationships among the key variables examined.These findings have important policy implications for the management of environmental quality and macroeconomic variables in the OECD context.展开更多
Cloud-based setups are intertwined with the Internet of Things and advanced,and technologies such as blockchain revolutionize conventional healthcare infrastructure.This digitization has major advantages,mainly enhanc...Cloud-based setups are intertwined with the Internet of Things and advanced,and technologies such as blockchain revolutionize conventional healthcare infrastructure.This digitization has major advantages,mainly enhancing the security barriers of the green tree infrastructure.In this study,we conducted a systematic review of over 150 articles that focused exclusively on blockchain-based healthcare systems,security vulnerabilities,cyberattacks,and system limitations.In addition,we considered several solutions proposed by thousands of researchers worldwide.Our results mostly delineate sustained threats and security concerns in blockchain-based medical health infrastructures for data management,transmission,and processing.Here,we describe 17 security threats that violate the privacy and data integrity of a system,over 21 cyber-attacks on security and QoS,and some system implementation problems such as node compromise,scalability,efficiency,regulatory issues,computation speed,and power consumption.We propose a multi-layered architecture for the future healthcare infrastructure.Second,we classify all threats and security concerns based on these layers and assess suggested solutions in terms of these contingencies.Our thorough theoretical examination of several performance criteria—including confidentiality,access control,interoperability problems,and energy efficiency—as well as mathematical verifications establishes the superiority of security,privacy maintenance,reliability,and efficiency over conventional systems.We conducted in-depth comparative studies on different interoperability parameters in the blockchain models.Our research justifies the use of various positive protocols and optimization methods to improve the quality of services in e-healthcare and overcome problems arising fromlaws and ethics.Determining the theoretical aspects,their scope,and future expectations encourages us to design reliable,secure,and privacy-preserving systems.展开更多
In underground coal mines, uncontrolled accumulation of methane and fine coal dust often leads to serious incidents such as explosion. Therefore, methane and dust dispersion in underground mines is closely monitored a...In underground coal mines, uncontrolled accumulation of methane and fine coal dust often leads to serious incidents such as explosion. Therefore, methane and dust dispersion in underground mines is closely monitored and strictly regulated. Accordingly, significant efforts have been devoted to study methane and dust dispersion in underground mines. In this study, methane emission and dust concentration are numerically investigated using a computational fluid dynamics(CFD) approach. Various possible scenarios of underground mine configurations are evaluated. The results indicate that the presence of continuous miner adversely affects the air flow and leads to increased methane and dust concentrations.Nevertheless, it is found that such negative effect can be minimized or even neutralized by operating the scrubber fan in suction mode. In addition, it was found that the combination of scrubber fan in suction mode and brattice results in the best performance in terms of methane and dust removal from the mining face.展开更多
The influence of surface-modified silica(SiO_2) nanoparticles on the stability and pore plugging properties of foams in porous media was investigated in this study. The pore plugging ability of foams was estimated fro...The influence of surface-modified silica(SiO_2) nanoparticles on the stability and pore plugging properties of foams in porous media was investigated in this study. The pore plugging ability of foams was estimated from the pressure drop induced during foam propagation in porous media. The results clearly showed that the modified Si02 nanoparticlestabilized foam exhibited high stability, and the differential pressure increased in porous media by as much as three times.The addition of SiO_2 nanoparticles to the foaming dispersions further mitigated the adverse effect of oil toward the foam pore plugging ability. Consequently, the oil recovery increased in the presence of nanoparticles by approximately 15%during the enhanced oil recovery experiment. The study suggested that the addition of surface-modified silica nanoparticles to the surfactant solution could considerably improve the conventional foam stability and pore plugging performance in porous media.展开更多
基金supported by Petronas Research Sdn Bhd(PRSB)with grant number(015M20-129)Centre of Research in Ionic Liquids(CORIL)Universiti Teknologi PETRONAS for the facilities and support provided。
文摘The study introduces eco-friendly leaching agents as alternatives to traditional rare earth element(REE)extraction solvents,addressing environmental concerns associated with ammonium sulfate.Bio-based ionic liquids(ILs),known for their non-toxic and biodegradable properties,were screened using the COSMO-RS software.Initially,105 ILs involving 7 cations and 15 anions were computationally screened to find the best ILs for REE extraction.The chosen criteria were based on hydrogen bond formation,affinity screening,hydrophobicity,viscosity,and eco-toxicity test.Based on the COSMO-RS screening,choline oleate,choline decanoate,and choline hexanoate exhibit high solubility for REEs,with a chemical potential of 17.60,17.01,and 18.37 kcal/mol at REE oxidation state+2.Choline glycinate,choline oleate,choline decanoate,choline hexanoate,choline lysinate,and choline leucinate were selected for their strong affinity to extract REE dissociate ions.Experimental results show slightly higher REE extraction from ammonium sulfate(3.17 ppm)compared to choline glycinate(3.15 ppm).For long-term applications,choline glycinate offers a promising eco-friendly and cost-effective alternative to traditional leaching agents,promoting economic feasibility and environmental friendliness.
基金Ministry of Science and Higher Education of the Russian Federation,Grant/Award Number:FSNM-2024-0005Korea Institute of Energy Technology Evaluation and Planning,Grant/Award Number:20225B10300080Yayasan UTP,Grant/Award Number:015LC0-526。
文摘Carbon capture and storage(CCS)remains one of the most feasible techniques for the control of Greenhouse gas emission levels.However,there will always be risks attached to the subsurface injection of CO_(2).These could be in the form of leakages from the injection wellbore due to completion failure;escape of the injected CO_(2)to neighboring aquifers due to the heterogeneous or fractured nature of the storage site;or seepage at the surface due to inadequacy of the sealing cap rock.While all these may occur,the most cost-effective and timely way to reduce the risk of leakages is by plugging the pathways.This is done using either traditional Cementous materials or more augmented sealants like organic gels and resins.A lot of studies in the literature have described this collection of materials within the context of CO_(2)conformance control.So also,there are reviews on the classification and description of these chemicals.This review provides a more systemic evaluation of these classes of chemicals.This is by providing critical analyses of how external factors like CO_(2),pH,brine salinity and hardness,rock mineralogy,pressure,temperature,and injectivity could affect the performance of different sealants that can be utilized.Based on these assessments,best practices for the application of the sealants,both at the testing stage in the laboratory and the pilot stage and field deployment,are suggested.
文摘Geological CO_(2) storage is a promising strategy for reducing greenhouse gas emissions;however,its underlying multiphase reactive flow mechanisms remain poorly understood.We conducted steady-state imbibition relative permeability experiments on sandstone from a proposed storage site,comple-mented by in situ X-ray imaging and ex situ analyses using scanning electron microscopy(SEM)and energy-dispersive X-ray spectroscopy(EDS).Despite our use of a brine that was pre-equilibrated with CO_(2),there was a significant reduction in both CO_(2) relative permeability and absolute permeability during multiphase flow due to chemical reactions.This reduction was driven by decreased pore and throat sizes,diminished connectivity,and increased irregularity of pore and throat shapes,as revealed by in situ pore-scale imaging.Mineral dissolution,primarily of feldspar,albite,and calcite,along with precipitation resulting from feldspar-to-kaolinite transformation and fines migration,were identified as contributing factors through SEM-EDS analysis.This work provides a benchmark for storage in mineralogically complex sandstones,for which the impact of chemical reactions on multiphase flow properties has been measured.
文摘A full-scale research study was conducted during the bored tunnelling of the Klang Valley Mass Rapid Transit-Putrajaya Line beneath an existing building structure in Kuala Lumpur,Malaysia.The primary objective was to investigate the tunnel-soil-pile interaction at various stages of tunnel excavation.This study combined field measurements and three-dimensional(3D)numerical analysis to understand the transient effects of TBM tunnelling on a loaded pile.An experimental pile was instrumented with vibrating wire strain gauges,an inclinometer,and distributed fibre optic sensors using Brillouin optical time domain analysis.The pile was pre-loaded and continuously monitored in real-time throughout the tunnel construction process.The 3D finite element modelling was used to simulate the pile’s transient responses based on actual tunnel boring machine(TBM)driving data.The study revealed that the zone of influence due to tunnelling effects extended from y¼2D to y¼4D,with the peak effect observed at y¼1D to 1.5D,where D represents the tunnel diameter.The analysis of axial load patterns highlighted transient responses,including tensile loads below the tunnel invert,which propagated upward and subsided due to negative skin friction.The maximum downdrag load observed reached 56%e71%of the pile’s working load.Additionally,pile movement patterns indicated outward deflections as the TBM approached and a return toward the tunnel post-passage,aligning with the predicted behaviour in a negative face loss scenario.This validated numerical framework provides a solid foundation for further parametric studies and enhances the understanding of tunnel-soil-pile interactions.
基金Universiti Teknologi PETRONAS for the financial support provided through the YUTP-FRG grant(015LC0-631).
文摘Polymeric materials have emerged as a promising alternative to electrolytic solutions in energy storage applications.However,high crystallinity and poor ionic conductivity are the main barriers restricting their daily application.In this study,we propose a polymer electrolyte system consisting of methylcellulose-polyvinyl alcohol(MC-PVA)blend as host material and lithium trifluoromethanesulfonate(LiCF_(3)SO_(3))as dopant,which was prepared using the solution-casting method.The electrochemical impedance spectroscopy(EIS)analysis revealed a maximum conductivity of 5.42×10^(−6) S cm^(−1) with 40 wt.%LiCF_(3)SO_(3).The key findings demonstrated that the variation in the dielectric loss(εi)and dielectric constant(εr)was significantly correlated with the variation in ionic conductivity.Fourier-transform infrared spectroscopy(FTIR)analysis was done to analyse the salt-polymer interaction by observing the shifting of selected bands.By deconvoluting FTIR spectra in the wavenumber range of 970–1100 cm^(−1),transport properties of electrolytes were investigated and found to be improved when the salt concentration was increased to 40 wt.%.Results from the X-ray diffraction(XRD)study suggested that the higher salt concentration promoted the formation of an amorphous phase,which is favourable for ionic conduction.Field emission scanning electron microscopy(FESEM)study demonstrated that the addition of salt altered the surface morphology of MC-PVA.
基金supported by the Yayasan Universiti Teknologi PETRONAS(YUTP)under Cost Center 015LC0-485.
文摘Unmanned aerial vehicles(UAVs)technology is rapidly advancing,offering innovative solutions for various industries,including the critical task of oil and gas pipeline surveillance.However,the limited flight time of conventional UAVs presents a significant challenge to comprehensive and continuous monitoring,which is crucial for maintaining the integrity of pipeline infrastructure.This review paper evaluates methods for extending UAV flight endurance,focusing on their potential application in pipeline inspection.Through an extensive literature review,this study identifies the latest advancements in UAV technology,evaluates their effectiveness,and highlights the existing gaps in achieving prolonged flight operations.Advanced techniques,including artificial intelligence(AI),machine learning(ML),and deep learning(DL),are reviewed for their roles in pipeline monitoring.Notably,DL algorithms like You Only Look Once(YOLO)are explored for autonomous flight in UAV-based inspections,real-time defect detection,such as cracks,corrosion,and leaks,enhancing reliability and accuracy.A vital aspect of this research is the proposed deployment of a hybrid drone design combining lighter-than-air(LTA)and heavier-than-air(HTA)principles,achieving a balance of endurance and maneuverability.LTA vehicles utilize buoyancy to reduce energy consumption,thereby extending flight durations.The paper details the methodology for designing LTA vehicles,presenting an analysis of design parameters that align with the requirements for effective pipeline surveillance.The ongoing work is currently at Technology Readiness Level(TRL)4,where key components have been validated in laboratory conditions,with fabrication and flight testing planned for the next phase.Initial design analysis indicates that LTA configurations could offer significant advantages in flight endurance compared to traditional UAV designs.These findings lay the groundwork for future fabrication and testing phases,which will be critical in validating and assessing the proposed approach’s real-world applicability.By outlining the technical complexities and proposing specialized techniques tailored for pipeline monitoring,this paper provides a foundational framework for advancing UAV capabilities in the oil and gas sector.Researchers and industry practitioners can use this roadmap to further develop UAV-enabled surveillance solutions,aiming to improve the reliability,efficiency,and safety of pipeline monitoring.
文摘Enhanced oil recovery(EOR)refers to themanymethodologies used to augment the volume of crude oil extracted froman oil reservoir.These approaches are used subsequent to the exhaustion of basic and secondary recovery methods.There are three primary categories of Enhanced Oil Recovery(EOR):thermal,gas injection,and chemical.Enhanced oil recovery methods may be costly and intricate;yet,they facilitate the extraction of supplementary oil that would otherwise remain in the reservoir.Enhanced Oil Recovery(EOR)may prolong the lifespan of an oil field and augment the total output from a specific field.The parameters influencing oil recovery are a significant problem in Enhanced Oil Recovery(EOR)systems,necessitating further examination of the components that impact them.This research examined the impact of permeability fluctuations on fluid dynamics inside a sandstone reservoir and presented a contemporary overview of the three phases of Enhanced Oil Recovery(EOR),including detailed explanations of the methodologies used and the processes facilitating oil recovery.The challenges faced with several common EOR mechanisms were identified,and solutions were suggested.Additionally,the modern trend of incorporating nanotechnology and its synergistic impacts on the stability and efficacy of conventional chemicals for enhanced oil recovery(EOR)was scrutinised and evaluated.Ultimately,laboratory results and field activities were examined.The study looked closely at hownanoparticlesmove through reservoirs and evaluated enhanced oil recovery(EOR),mobility ratio,and fluid displacement efficiency.This study offers comprehensive insights into the use of enhanced oil recovery techniques for sustainable energy generation.
文摘Atrium spaces,common in modern construction,provide significant fire safety challenges due to their large vertical openings,which facilitate rapid smoke spread and reduce sprinkler effectiveness.Traditional smoke management systems primarily rely on make-up air to replace the air expelled through vents.Inadequate calibration,particularly with air velocity,can worsen fire conditions by enhancing oxygen supply,increasing soot production,and reducing visibility,so endangering safe evacuation.This study investigates the impact of make-up air velocity on smoke behaviour in atrium environments through 24 simulations performed using the FireDynamics Simulator(FDS).Scenarios include various fire intensities(1,3,5 MW)and make-up air velocities(1–3.5 m/s),with fire sources located at the centre,northeast,and southwest corners.The simulation model was validated using updated full-scale fire test data with polystyrene fuel,leading to heightened soot density and reduced smoke clear height.This Research design diverges from other studies that predominantly utilized propane pool fires and concentrated on axisymmetric(Fire at the center of the atrum),Northeast and Southeast corners of the atrium scenarios by using polystyrene-a widely accessible construction material and examining several asymetric fire sites,so providing a more authentic depiction of atrium fire settings.Research reveals that increased air velocities,especially when directed at the fire,result in greater soot density and reduced smoke clearance due to intensified combustion.The northeastern region consistently displayed high temperature readings,highlighting the importance of fire source positioning in smoke behaviour.The study recommends limiting make-up air velocity to 1 m/s to avert turbulence and guarantee safety.This research provides critical insights for fire safety design and aligns with the United Nations Sustainable Development Goals,namely SDG 9 and SDG 11,by promoting safer and more resilient construction practices in urban environments.
基金funded by the Geran Universiti Penyelidikan(GUP),under the grant number GUP-2022-011 funded by the Universiti Kebangsaan Malaysia。
文摘This study presents a detailed comparative analysis of three electron transport layer(ETL)materials for perovskite solar cells(PSCs),namely titanium dioxide(TiO_(2)),barium titanate(BaTiO_(3)or BTO),and strontium-doped barium titan-ate(Ba_(1−x)Sr_(x)TiO_(3)or BST),and their impact on the quantum efficiency(QE)and power conversion efficiency(PCE)of CH_(3)NH_(3)PbI_(3)(MAPbI_(3))PSCs.The optimized structure demonstrates that devices utilizing BST as an ETL achieved the highest PCE of 29.85%,exhibiting superior thermal stability with the lowest temperature coefficient of−0.43%/K.This temperature-induced degradation is comparable to that of commercially available silicon cells.Furthermore,BST-based ETLs show 29.50%and 26.48%higher PCE than those of TiO_(2)-based and BTO-based ETLs.The enhanced internal QE and favorable current density–voltage(J–V)characteristics of BST compared with those of TiO_(2)and BTO are attributed to its improved charge carrier separation,reduced recombination rates,and robust electrical characteristics under varied environmental conditions.Furthermore,the electric field and generation rate of the BST-based ETLs show a more favorable distribution than those of the TiO_(2)-based and BTO-based ETLs.These findings provide significant insights into the role of different ETLs in enhancing QE,indicating that BST is a superior ETL that enhances both the efficiency and stability of PSCs.This study contributes to the understanding of how perovskite-structured ETLs can be used to design and optimize highly efficient and stable photovoltaic devices.
基金Supporting Project number(RSP2025R92)at King Saud University,Riyadh,Saudi Arabia,for their support.
文摘The importance of organic geochemistry and basin modeling is widely recognized and used to understand the source rock potential and hydrocarbon generation history of the Mangahewa Formation,and thereby given the foundational role in the petroleum exploration.This study utilized the total organic carbon(TOC)content and hydrogen index(HI)to investigate the dominant kerogen type and hydrogen richness for the significance of petroleum generative potential.The Mangahewa coals and carbonaceous shales exhibit an excellent source rocks,with high total organic content(TOC)of more than 22%.The coals and carbonaceous shales were also characterised by Type Ⅱ‒Ⅲ kerogen with Type Ⅲ kerogen,promising oiland gas-prones.The Mangahewa Formation reached the main oil generation,with vitrinite reflectances between 0.53%and 1.01%.Vitrinite reflectance was also used in developing themal models and reveal the transformation(TR)of 10‒50%kerogen to oil during the Late Miocene.The models also showed that the Mangahewa source rock has a significant oil generation and little expulsion competency,with a TR of up to 54%.These findings support the substantial oil-generating potential in the Taranaki Basin's southern graben and can be used as a guide when developing strategies for an oil exploration program.
基金funded by Scientific Research Deanship at University of Hail-Saudi Arabia through Project Number RG-23092.
文摘Cyberbullying on social media poses significant psychological risks,yet most detection systems over-simplify the task by focusing on binary classification,ignoring nuanced categories like passive-aggressive remarks or indirect slurs.To address this gap,we propose a hybrid framework combining Term Frequency-Inverse Document Frequency(TF-IDF),word-to-vector(Word2Vec),and Bidirectional Encoder Representations from Transformers(BERT)based models for multi-class cyberbullying detection.Our approach integrates TF-IDF for lexical specificity and Word2Vec for semantic relationships,fused with BERT’s contextual embeddings to capture syntactic and semantic complexities.We evaluate the framework on a publicly available dataset of 47,000 annotated social media posts across five cyberbullying categories:age,ethnicity,gender,religion,and indirect aggression.Among BERT variants tested,BERT Base Un-Cased achieved the highest performance with 93%accuracy(standard deviation across±1%5-fold cross-validation)and an average AUC of 0.96,outperforming standalone TF-IDF(78%)and Word2Vec(82%)models.Notably,it achieved near-perfect AUC scores(0.99)for age and ethnicity-based bullying.A comparative analysis with state-of-the-art benchmarks,including Generative Pre-trained Transformer 2(GPT-2)and Text-to-Text Transfer Transformer(T5)models highlights BERT’s superiority in handling ambiguous language.This work advances cyberbullying detection by demonstrating how hybrid feature extraction and transformer models improve multi-class classification,offering a scalable solution for moderating nuanced harmful content.
文摘Energy efficiency stands as an essential factor when implementing deep reinforcement learning(DRL)policies for robotic control systems.Standard algorithms,including Deep Deterministic Policy Gradient(DDPG),primarily optimize task rewards but at the cost of excessively high energy consumption,making them impractical for real-world robotic systems.To address this limitation,we propose Physics-Informed DDPG(PI-DDPG),which integrates physics-based energy penalties to develop energy-efficient yet high-performing control policies.The proposed method introduces adaptive physics-informed constraints through a dynamic weighting factor(λ),enabling policies that balance reward maximization with energy savings.Our motivation is to overcome the impracticality of rewardonly optimization by designing controllers that achieve competitive performance while substantially reducing energy consumption.PI-DDPG was evaluated in nine MuJoCo continuous control environments,where it demonstrated significant improvements in energy efficiency without compromising stability or performance.Experimental results confirm that PI-DDPG substantially reduces energy consumption compared to standard DDPG,while maintaining competitive task performance.For instance,energy costs decreased from 5542.98 to 3119.02 in HalfCheetah-v4 and from1909.13 to 1586.75 in Ant-v4,with stable performance in Hopper-v4(205.95 vs.130.82)and InvertedPendulum-v4(322.97 vs.311.29).Although DDPG sometimes yields higher rewards,such as in HalfCheetah-v4(5695.37 vs.4894.59),it requires significantly greater energy expenditure.These results highlight PI-DDPG as a promising energy-conscious alternative for robotic control.
基金funding support from Arabian Gulf University to cover any necessary publication fees.
文摘Integrating the photovoltaic/thermal(PV/T)system in green hydrogen production is an improvement in sustainable energy technologies.In PV/T systems,solar energy is converted into electricity and thermal energy simultaneously using hot water or air together with electricity.This dual use saves a significant amount of energy and officially fights greenhouse gases.Different cooling techniques have been proposed in the literature for improving the overall performance of the PV/T systems;employing different types of agents including nanofluids and phase change materials.Hydrogen is the lightest and most abundant element in the universe and has later turned into a flexible energy carrier for transportation and other industrial applications.Issues,including the processes of Hydrogen manufacturing,preservation as well as some risks act as barriers.This paper provides an analysis of several recent publications on the efficiency of using PV/T technology in the process of green hydrogen production and indicates the potential for its increased efficiency as compared to conventional systems that rely on fossil fuels.Due to the effective integration of solar energy,the PV/T system can play an important role in the reduction of the levelized cost of hydrogen(LCOH)and hence play an important part in reducing the economic calculations of the decarbonized energy system.
文摘Photocatalysis is a crucial technique for environmental cleanup and renewable energy generation.Polymer-based photocatalysts have attracted interest due to their adaptability,adjustable chemical characteristics,and enhanced light absorption efficiency.Unlike traditional inorganic photocatalysts,we can optimize polymeric systems to enhance photocatalytic efficiency and yield significant advantages in environmental remediation and energy conversion applications.This study talks about the latest developments in polymer-based photocatalysts and how important they are for cleaning water,breaking down pollutants,and making renewable energy through processes like hydrogen production and CO_(2) reduction.These materials are proficient in degrading harmful pollutants such as organic colours,insecticides,and medications,transforming them into innocuous byproducts.Moreover,its use in solar-driven water splitting for hydrogen production and CO_(2) reduction provides a sustainable solution to global energy and environmental issues.These photocatalysts are much more effective and last longer thanks to progress in polymer chemistry,nano-structuring,and hybridization with materials like semiconductors and metal nanoparticles.The research underscores the promise of polymer photocatalysts for extensive environmental applications due to their cost-efficiency,ease of separation,and reusability.Future research endeavors seek to optimize polymeric photocatalyst systems for improved stability and performance,hence advancing sustainable solutions for critical environmental and energy challenges.
文摘The asphalt pavement industry is transforming because of the growing influence of artificial intelligence and industrial digitization.As a result of this shift,there is a stronger emphasis on advanced statistical approaches like optimization tools like response surface methodology(RSM)and machine learning(ML)techniques.The goal of this paper is to provide a scientometric and systematic review of the application of RSM and ML applications in data-driven approaches such as optimizing,modeling,and predicting asphalt pavement performance to achieve sustainable asphalt pavements in support of numerous sustainable development goals(SDGs).These include Goals 9(sustainable infrastructure),11(urban resilience),12(sustainable construction strategies),13(climate action through optimized materials),and 17(multidisciplinary interaction).A thorough search of the ScienceDirect,Web of Science,and Scopus databases from 2010 to 2023 yielded 1249 relevant records,with 125 studies closely examined.Over the last thirteen years,there has been significant research growth in RSM and ML applications,particularly in ML-based pavement optimization.The study shows that the topic has a global presence,with notable contributions from Asia,North America,Europe,and other continents.Researchers have concentrated on utilizing sophisticated ML models such as support vector machines(SVM),artificial neural networks(ANN),and Bayesian networks for prediction.Also,the integration of RSM and ML provides a faster and more efficient method for analyzing large datasets to optimize asphalt pavement performance variables.Key contributors include the United States,China,and Malaysia,with global efforts focused on sustainable materials and approaches to reduce impact on the environment.Furthermore,the review demonstrates the integrated use of RSM and ML as transformative tools for improving sustainability,which contributes significantly to SDGs 9,11,12,13,and 17.Providing valuable insights for future research and guiding decision-making for soft computing applications for asphalt pavement projects.
文摘This research extends the literature on the environmental Phillips curve(EPC)and environmental Kuznets curve(EKC)by focusing on the 38 member economies of the Organization for Economic Co-operation and Development(OECD).Using panel data from 2000 to 2021,the study employs several econometric techniques,including fixed effects,feasible generalized least squares,two-stage least squares,and the generalized method of moments.Our primary findings reveal that unemployment has a significant negative impact on CO_(2)emissions,thereby supporting the validity of the EPC hypothesis within OECD countries.This suggests a trade-off between unemployment and reductions in CO_(2)emissions.Similarly,the results validate the EKC hypothesis,with further analysis indicating that the EKC exhibits an N-shaped curve-an important contribution to the literature on environmental dynamics in advanced economies.Additionally,the results show that both trade openness and renewable energy usage have significantly improved environmental quality in OECD economies.Finally,extensive causality testing identifies both one-way and two-way causal relationships among the key variables examined.These findings have important policy implications for the management of environmental quality and macroeconomic variables in the OECD context.
文摘Cloud-based setups are intertwined with the Internet of Things and advanced,and technologies such as blockchain revolutionize conventional healthcare infrastructure.This digitization has major advantages,mainly enhancing the security barriers of the green tree infrastructure.In this study,we conducted a systematic review of over 150 articles that focused exclusively on blockchain-based healthcare systems,security vulnerabilities,cyberattacks,and system limitations.In addition,we considered several solutions proposed by thousands of researchers worldwide.Our results mostly delineate sustained threats and security concerns in blockchain-based medical health infrastructures for data management,transmission,and processing.Here,we describe 17 security threats that violate the privacy and data integrity of a system,over 21 cyber-attacks on security and QoS,and some system implementation problems such as node compromise,scalability,efficiency,regulatory issues,computation speed,and power consumption.We propose a multi-layered architecture for the future healthcare infrastructure.Second,we classify all threats and security concerns based on these layers and assess suggested solutions in terms of these contingencies.Our thorough theoretical examination of several performance criteria—including confidentiality,access control,interoperability problems,and energy efficiency—as well as mathematical verifications establishes the superiority of security,privacy maintenance,reliability,and efficiency over conventional systems.We conducted in-depth comparative studies on different interoperability parameters in the blockchain models.Our research justifies the use of various positive protocols and optimization methods to improve the quality of services in e-healthcare and overcome problems arising fromlaws and ethics.Determining the theoretical aspects,their scope,and future expectations encourages us to design reliable,secure,and privacy-preserving systems.
基金financial support from McGill University-Canada and NSERC-Discovery Grant RGPIN-2015-03945
文摘In underground coal mines, uncontrolled accumulation of methane and fine coal dust often leads to serious incidents such as explosion. Therefore, methane and dust dispersion in underground mines is closely monitored and strictly regulated. Accordingly, significant efforts have been devoted to study methane and dust dispersion in underground mines. In this study, methane emission and dust concentration are numerically investigated using a computational fluid dynamics(CFD) approach. Various possible scenarios of underground mine configurations are evaluated. The results indicate that the presence of continuous miner adversely affects the air flow and leads to increased methane and dust concentrations.Nevertheless, it is found that such negative effect can be minimized or even neutralized by operating the scrubber fan in suction mode. In addition, it was found that the combination of scrubber fan in suction mode and brattice results in the best performance in terms of methane and dust removal from the mining face.
基金Ministry of Higher Education (Vot No. Q.J130000.2542.08H61)Universiti Teknologi (UTM) Malaysia for supporting this research
文摘The influence of surface-modified silica(SiO_2) nanoparticles on the stability and pore plugging properties of foams in porous media was investigated in this study. The pore plugging ability of foams was estimated from the pressure drop induced during foam propagation in porous media. The results clearly showed that the modified Si02 nanoparticlestabilized foam exhibited high stability, and the differential pressure increased in porous media by as much as three times.The addition of SiO_2 nanoparticles to the foaming dispersions further mitigated the adverse effect of oil toward the foam pore plugging ability. Consequently, the oil recovery increased in the presence of nanoparticles by approximately 15%during the enhanced oil recovery experiment. The study suggested that the addition of surface-modified silica nanoparticles to the surfactant solution could considerably improve the conventional foam stability and pore plugging performance in porous media.
