This study examines the connection between academic achievement and student attendance in early morning engineering classes, offering insights into the benefits and difficulties of early course scheduling. The study c...
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Sampling and communication are both crucial for coordination in multi-agent systems(MASs), with sampling capturing raw data from the environment for control decision making, and communication ensuring the data is shar...
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Sampling and communication are both crucial for coordination in multi-agent systems(MASs), with sampling capturing raw data from the environment for control decision making, and communication ensuring the data is shared effectively for synchronized and informed control decisions across agents. However, practical MASs often operate in environments where continuous and synchronous data samplings and exchanges are impractical, necessitating strategies that can handle intermittent sampling and communication constraints. This paper provides a comprehensive survey of recent advances in distributed coordination control of MASs under intermittent sampling and communication, focusing on both foundational principles and state-of-the-art techniques. After introducing fundamentals, such as communication topologies,agent dynamics, control laws, and typical coordination objectives, the distinctions between sampling and communication are elaborated, exploring deterministic versus random, synchronous versus asynchronous, and instantaneous versus sequential scenarios. A detailed review of emerging trends and techniques is then presented, covering time-triggered, event-triggered,communication-protocol-based, and denial-of-service-resilient coordination control. These techniques are analyzed across various attack models, including those based on data loss, sampled data, time constraints, and topology switching. By synthesizing these developments, this survey aims to equip researchers and practitioners with a clearer understanding of current challenges and methodologies, concluding with insights into promising future directions.
Event-triggered control(ETC) offers an efficient strategy for significantly reducing communication and computation resources in networked systems by triggering control updates only when necessary. This study provides ...
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Event-triggered control(ETC) offers an efficient strategy for significantly reducing communication and computation resources in networked systems by triggering control updates only when necessary. This study provides an overview of recent advances in ETC. First, data-driven(or model-free) ETC, which has gained significant attention in recent years, is reviewed for linear systems with and without unknown disturbances. Second, co-design issues are deeply analyzed for both state feedback and dynamic output feedback control. Third, the separation principle is thoroughly examined in the context of event-triggered observer-based output feedback control. Fourth, some insightful discussions are made on the ideal execution property of event-triggered schemes, as well as the modeling of ETC under packet dropouts. Finally, several challenging issues for future research are outlined.
Highway safety researchers focus on crash injury severity,utilizing deep learning—specifically,deep neural networks(DNN),deep convolutional neural networks(D-CNN),and deep recurrent neural networks(D-RNN)—as the pre...
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Highway safety researchers focus on crash injury severity,utilizing deep learning—specifically,deep neural networks(DNN),deep convolutional neural networks(D-CNN),and deep recurrent neural networks(D-RNN)—as the preferred method for modeling accident *** learning’s strength lies in handling intricate relation-ships within extensive datasets,making it popular for accident severity level(ASL)prediction and *** prior success,there is a need for an efficient system recognizing ASL in diverse road *** address this,we present an innovative Accident Severity Level Prediction Deep Learning(ASLP-DL)framework,incorporating DNN,D-CNN,and D-RNN models fine-tuned through iterative hyperparameter selection with Stochastic Gradient *** framework optimizes hidden layers and integrates data augmentation,Gaussian noise,and dropout regularization for improved *** and factor contribution analyses identify influential *** on three diverse crash record databases—NCDB 2018–2019,UK 2015–2020,and US 2016–2021—the D-RNN model excels with an ACC score of 89.0281%,a Roc Area of 0.751,an F-estimate of 0.941,and a Kappa score of 0.0629 over the NCDB *** proposed framework consistently outperforms traditional methods,existing machine learning,and deep learning techniques.
This study evaluates the effectiveness of corn cob charcoal, an agricultural waste product, as a carbon source in the pack carburizing process. The corn cob charcoal was prepared by burning, grinding into powder, and ...
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This study evaluates the effectiveness of corn cob charcoal, an agricultural waste product, as a carbon source in the pack carburizing process. The corn cob charcoal was prepared by burning, grinding into powder, and sieving. The resulting charcoal powder was then combined with calcium carbonate powder to form the carburizing mixture. AISI 1020 low-carbon steel specimens underwent pack carburization at temperatures of 960, 980, and 1,000 °C for 60, 90, and 120 min, respectively. The specimens were subsequently austenitized at 780 °C for 15 min, quenched in water, and tempered at 180 °C for 1 h. The results indicate significant effects on yield strength, tensile strength, and Young’s modulus, with R2 values demonstrating a high level of explanatory power. However, while temperature significantly influences % elongation, time does not. Additionally, the diffusion coefficient, calculated using Fick’s second law from the microhardness profile, increased with carburizing temperature and time.
This paper presents a novel approach of establishing a multichannel optical communication link, combining optical fiber cable (OFC) and free space optics (FSO) technology. By leveraging multiple lengths of optical fib...
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This study aims to investigate the influence of various vegetation patches with varying porosities on the hydraulic properties of a vegetated open channel under subcritical flow *** research work investigated three ty...
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This study aims to investigate the influence of various vegetation patches with varying porosities on the hydraulic properties of a vegetated open channel under subcritical flow *** research work investigated three types of vegetation patches:Rigid,flexible,and a combination of the *** total five vegetation patches with three different porosities for each patch were *** of these vegetation patches on various hydraulic parameters such as backwater rise,energy reduction,water surface slope in the vegetation patch,hydraulic jump formation on the downstream side of the vegetation patch,reduction in fluid force index(RFI),moment index(RMI),overflow volume(ΔQ)were *** findings revealed that the backwater rise increased in the case of rigid patch as the initial Froude number increased,whereas it decreased in the case of flexible and combined vegetation *** was observed that as the porosity increased from low(P_(r)=0.90)to high(P_(r)=0.99),the backwater rise decreased for all vegetation *** relative energy reduction rate increased for the rigid patch and showed a reverse trend for the flexible and combined vegetation patches with increasing initial Froude *** the combined vegetation arrangement,the energy reduction values were highest for the alternate rigid and flexible(ARF)vegetation patches and lowest for the longitudinal rigid and flexible(LRF)vegetation *** study identified the presence of a hydraulic jump downstream of the vegetation patch,as indicated by the Froude number in the range of 1.0–*** study also found that RFI,RMI,ΔQ had the highest values of 19.05%,19.05%,80.20%.The results of this study provide insight into the impact of vegetation patches with varying porosities on open-channel flow characteristics and can help develop sustainable vegetation management strategies.
All-vanadium flow batteries(VFBs) are one of the most promising large-scale energy storage *** an operando quantitative analysis of the polarizations in VFBs under different conditions is essential for developing hi...
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All-vanadium flow batteries(VFBs) are one of the most promising large-scale energy storage *** an operando quantitative analysis of the polarizations in VFBs under different conditions is essential for developing high power density ***,we employ an operando decoupling method to quantitatively analyze the polarizations in each electrochemical and chemical reaction of VFBs under different catalytic *** show that the reduction reaction of V3+presents the largest activation polarization,while the reduction reaction of VO2+primarily contributes to concentration polarizations due to the formation of the intermediate product V2O3+.Additionally,it is found that the widely used electrode catalytic methods,incorporating oxygen functional groups and electrodepositing Bi,not only enhance the reaction kinetics but also exacerbate concentration polarizations simultaneously,especially during the discharge ***,in the battery with the high oxygen-containing electrodes,the negative side still accounts for the majority of activation loss(75.3%) at 200 mA cm-2,but it comes down to 36,9% after catalyzing the negative reactions with *** work provides an effective way to probe the limiting steps in flow batteries under various working conditions and offers insights for effectively enhancing battery performance for future developments.
The urgent need to mitigate climate change impacts and achieve net zero emissions has led to extensive research on carbon dioxide(CO_(2))-capture *** study focuses on the kinetics of CO_(2)capture using solid adsorben...
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The urgent need to mitigate climate change impacts and achieve net zero emissions has led to extensive research on carbon dioxide(CO_(2))-capture *** study focuses on the kinetics of CO_(2)capture using solid adsorbents specifically through thermal gravimetric analysis(TGA).The research explores the principles behind TGA and its application in analyzing adsorbent performance and the significance of kinetics in optimizing CO_(2)-capture *** adsorbents have gained significant attention due to their potential for efficient and cost-effective CO_(2)***,three different types of adsorbents,namely calcium-,tin-,and zirconium-based ones(quicklime:CaO,potassium stannate:K_(2)SnO_(3),and sodium zirconate:Na_(2)ZrO_(3)),in adsorbing high-temperature carbon dioxide were investigated;their quality and performance by various factors such as price,stability,non-toxicity,and efficiency are *** diffusion models and geometrical contraction models were the best-fitted models to explain the kinetic of these solid adsorbents for high-temperature CO_(2)sorption;it means the morphology is important for solid adsorbent *** minimum energy needed to start a reaction for K_(2)SnO_(3),Na_(2)ZrO_(3),and CaO,is 73.55,84.33,and 86.23 kJ·mol^(-1),respectively;with the lowest value being for potassium *** high-temperature CO_(2)adsorption performance of various solid adsorbents in regard with the rate of reaction followed the order of K_(2)SnO_(3)>CaO>>Na_(2)ZrO_(3),based on experiments and kinetic studies.
The urgent demand for clean energy solutions has intensified the search for advanced storage materials, with rechargeable alkali-ion batteries(AIBs) playing a pivotal role in electrochemical energy storage. Enhancing ...
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The urgent demand for clean energy solutions has intensified the search for advanced storage materials, with rechargeable alkali-ion batteries(AIBs) playing a pivotal role in electrochemical energy storage. Enhancing electrode performance is critical to addressing the increasing need for high-energy and high-power AIBs. Next-generation anode materials face significant challenges, including limited energy storage capacities and complex reaction mechanisms that complicate structural ***-based materials have emerged as promising candidates for AIBs due to their inherent advantages. Recent research has increasingly focused on the development of heterojunctions as a strategy to enhance the performance of Sn-based anode materials. Despite significant advances in this field, comprehensive reviews summarizing the latest developments are still sparse. This review provides a detailed overview of recent progress in Sn-based heterojunction-type anode materials. It begins with an explanation of the concept of heterojunctions, including their fabrication, characterization, and classification. Cuttingedge research on Sn-based heterojunction-type anodes for AIBs is highlighted. Finally, the review summarizes the latest advancements in heterojunction technology and discusses future directions for research and development in this area.
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