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Rheological and stability analysis of cement pastes incorporating silica-based wastes

Particuology 2024年第6期89卷 144-152页

作者： julia da rosa marti.s Janaíde Cavalcante Rocha dachamir Hotza Luciano senff Graduate Program in Materials science and Engineering(PPGMAT) Federal University of Santa Catarina(UFSC)Florianópolis88040-900SCBrazil Graduate Program in Civil Engineering(PPGEC) Federal University of Santa Catarina(UFSC)Florianópolis88040-900SCBrazil Graduate Program in Chemical Engineering(POsENQ) Federal University of Santa Catarina(UFSC)Florianópolis88040-900SCBrazil Department of Mobility Engineering Federal University of Santa Catarina(UFSC)Joinville89219-600SCBrazil

This study investigates the influence of waste characteristics,especially zeta potential,on the properties of cement pastes and *** focus is to evaluate the impact of the zeta potential of cement particles and waste materials on the sedimentation speed,rheology,and hardening time of stabilized cement *** Cement II F 40,retarder additive,silica,and fly ash were used in the *** pastes were prepared,and during the stabilization period,their rheological properties and pH were *** zeta potential and sedimentation speed of the cement and waste particles were measured at the pH that the pastes presented during the entire stabilization *** the stabilization period,the pastes were subjected to the hardening time *** zeta potential analyses revealed diverse values for the different powder types,with the cement particles exhibiting a zeta potential of−3.0 mV,the silica particles exhibiting−10.5 mV,and the fly ash particles exhibiting−20.3 *** influence of the high zeta potential modulus was observed on the sedimentation speed,with the solution containing fly ash exhibiting a speed of 40.01μm/s,whereas the solution containing only cement exhibited a speed of 99.38μm/*** the pastes,the results indicate that the presence of fly ash particles with a significantly negative zeta potential led to a 16%reduction in hardening time compared to particles with a lower modulus of zeta *** tests showed that the inclusion of fly ash particles prevented the formation of *** the zeta potential influenced agglomerate formation and hardening time,it was found to have no effect on yield stress or viscosity.

关键词： Wastes Zeta potential setting time Rheometry

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Resource management at the network edge for federated learning

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Digital Communications and Networks 2024年第3期10卷 765-782页

作者： silvana Trindade Luiz F.Bittencourt Nelson L.s.da Fonseca Institute of Computing State University of CampinasCampinasBrazil

Federated learning has been explored as a promising solution for training machine learning models at the network edge,without sharing private user *** limited resources at the edge,new solutions must be developed to leverage the software and hardware resources as the existing solutions did not focus on resource management for network edge,specially for federated *** this paper,we describe the recent work on resource manage-ment at the edge and explore the challenges and future directions to allow the execution of federated learning at the *** such as the discovery of resources,deployment,load balancing,migration,and energy effi-ciency are discussed in the paper.

关键词： Resource management Edge computing Federated learning Machine learning

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Capsule endoscopy and panendoscopy:A journey to the future of gastrointestinal endoscopy

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World Journal of Gastroenterology 2024年第10期30卷 1270-1279页

作者： Bruno rosa JoséCotter Department of Gastroenterology Hospital da Senhora da OliveiraGuimarães 4835-044Portugal Life and Health sciences Research Institute School of MedicineUniversity of MinhoBraga 4710-057Portugal ICVs/3B's PT Government Associate LaboratoryBraga 4710-057Portugal

In 2000,the small bowel capsule revolutionized the management of patients with small bowel ***,the technological development achieved by the new models of double-headed endoscopic capsules,as miniaturized devices to evaluate the small bowel and colon[pan-intestinal capsule endoscopy(PCE)],makes this non-invasive procedure a disruptive concept for the management of patients with digestive *** technology is expected to identify which patients will require conventional invasive endoscopic procedures(colonoscopy or balloon-assisted enteroscopy),based on the lesions detected by the capsule,i.e.,those with an indication for biopsies or endoscopic *** use of PCE in patients with inflammatory bowel diseases,namely Crohn’s disease,as well as in patients with iron deficiency anaemia and/or overt gastrointestinal(GI)bleeding,after a non-diagnostic upper endoscopy(esophagogastroduodenoscopy),enables an effective,safe and comfortable way to identify patients with relevant lesions,who should undergo subsequent invasive endoscopic *** recent development of magnetically controlled capsule endoscopy to evaluate the upper GI tract,is a further step towards the possibility of an entirely non-invasive assessment of all the segments of the digestive tract,from mouth-to-anus,meeting the expectations of the early developers of capsule endoscopy.

关键词： Non-invasive endoscopy Panendoscopy Magnetically controlled capsule endoscopy Crohn’s disease Digestive bleeding

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ENsO impacts on litter stocks and water holding capacity in secondary forests in eastern Amazonia

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Journal of Forestry Research 2024年第1期35卷 83-89页

作者： julia Isabella de Matos Rodrigues Walmer Bruno Rocha marti.s Victor Pereira de Oliveira Myriam suelen da silva Wanzerley Hélio Brito dos santos Júnior Francisco de Assis Oliveira Graduate Program in Forestry sciences Av.Presidente Tancredo Neves2501BelémPará66077-530Brazil Federal Rural University of Amazonia Av.Presidente Tancredo Neves2501BelémPará66077-530Brazil Federal Rural University of Amazonia Tv.Pau-AmareloCapitão PoçoPará68650-000Brazil National Institute of Amazonia Research Av.Constelação Cruzeiro do SulManausAmazonas 69060-062Brazil

Among the impacts of climate change,there is the intensification of phenomena such as the El Niño south-ern Oscillation(ENsO)responsible for El Niño and La Niñ***,understanding their effects on the functional pro-cesses of forests is ***,this study evaluated the effects of ENsO on litter stock and water holding capac-ity(WHC)in a successional forest in eastern *** occurred in periods with the most rainfall in El Niño(2019)and least in La Niña(2021)*** permanent plots were used to sample *** effects were evident for WHC,higher during El Niñ***,this influence was not clear for litter,as only in the rainy season effects were *** was a positive correlation of WHC with precipitation and humidity,while litter stocks were negatively correlated with temperature and wind *** the subject of this study requires long-term assessments,preliminary results suggests that,depending on the intensity of ENsO,forest functional processes can be strongly impacted and *** conclusion reinforces warnings by the scientific community about the impacts of climate change on the maintenance of litter stocks,decomposition and,consequently,the biogeochemical cycle and essential ecosystem services for the maintenance of Amazonia *** need to develop long-term research to understand the effects of climatic change on litter stocks and water holding capacity is highlighted,especially in Amazonia.

关键词： seasonality Climate change succession ecosystem Biogeochemical cycle Amazonia biodiversity

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Analysis of a passive ankle exoskeleton for reduction of metabolic costs during walking

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Defence Technology（防务技术） 2024年第7期37卷 62-68页

作者： Luís Quinto Pedro Pinheiro sergio B.Goncalves Ivo Roupa Paula simoes Miguel Tavares da silva CINAMIL Academia MilitarInstituto Universitario MilitarLisbonPortugal IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal

Modern conflicts demand substantial physical and psychological exertion,often resulting in fatigue and diminished combat or operational *** exoskeletons have been developed recently to address these challenges,presenting various limitations that affect their operational or everyday *** article evaluates the performance of a dual-purpose passive ankle exoskeleton developed for the reduction of metabolic costs during walking,seeking to identify a force element that could be applied to the target *** on the 6-min walk test,twenty-nine subjects participated in the study using three different force *** results indicate that it is possible to reduce metabolic expenditure while using the developed ***,the comfort and range of motion results verify the exoskeleton's suitability for use in uneven terrain and during extended ***,the choice of the force element should be tailored to each user,and the control system should be adjustable to optimise the exoskeleton's performance.

关键词： Ankle passive exoskeleton Metabolic cost reduction Dual-use exoskeleton Gait Biomechanics

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Influence of previous plane of nutrition on molecular mechanisms regulating the expression of urea and water metabolism related genes in the rumen and kidney of finishing crossbred Angus steers

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Animal Nutrition 2024年第2期17卷 232-243页

作者： Aghata E.Moreira da silva Arturo Macias Franco Bradley s.Ferguson Mozart A.Fonseca College of Agriculture Biotechnology&Natural Resources University of Nevada Department of Animal and Range sciences Clayton Livestock Research Center New Mexico State University

This study aimed to understand how molecular mechanisms controlling water and urea metabolism at the finishing phase can be affected by previous plane of nutrition of crossbred Angus beef steers. Twentyfour(n = 24) animals were randomly distributed into either a moderate(MP) or high plane of nutrition during the background phase for 85 d. Animals were then blocked by their previous plane and were moved onto a 105-d finishing phase in a 2 × 2 factorial arrangement. The forage-finished group received only high-quality alfalfa hay, whereas the grain-fed group received a high grain diet(80% whole corn and20% alfalfa hay). By the end of the finishing phase, animals were harvested and tissue samples from the rumen and kidney were collected. Changes in gene expression of aquaporins(AQP)-2,-3,-4,-7, ATP1A1,ATP1B1, sGK1, CLIC1(kidney and rumen), UT-A1(kidney only) and UT-B(rumen only), were assayed via real-time q PCR; 18s r RNA was used as an endogenous control. One-way ANOVA followed by Tukey's post hoc analysis was conducted. When animals were from MP, forage-finishing increased the relative abundance of AQP3(P ≤ 0.05), AQP7(P ≤ 0.05), ATP1B1(P ≤ 0.05), and sGK1(P ≤ 0.05) in the kidney when compared to grain-fed animals. In the rumen, for the MP group, AQP7 was differentially expressed in both treatments at the finishing phase(P ≤ 0.01), with forage-finished steers having the highest expression of AQP7. For the MP group, UT-B had a tendency of presenting a higher expression on grainfed animals(P = 0.075). Overall, these results suggest that previous plane can impact expression of genes associated with water and urea metabolism during the finishing phase, namely AQP3, AQP7, ATP1B1, and sGK1 in the kidney, and AQP7 and UT-B in the rumen. The greatest impact observed on gene expression changes of investigated genes at the finishing phase was reflective of animals backgrounded on the moderate previous plane.

关键词： Gene expression Aquaporin sodium channel Urea transporter

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study on 6-DOF active vibration-isolation system of the ultra-precision turning lathe based on GA-BP-PID control for dynamic loads

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Advances in Manufacturing 2024年第1期12卷 33-60页

作者： Bo Wang Zhong Jiang Pei-da Hu Department of Precision Instrument Tsinghua UniversityBeijing100084People’s Republic of China Institute of Machinery Manufacturing Technology China Academy of Engineering PhysicsMianyang621900SichuanPeople’s Republic of China

The vibration disturbance from an external environment affects the machining accuracy of ultra-precision machining *** active vibration-isolation systems(AVIs)have been developed based on static *** a vibration-isolation load changes dynamically during ultra-precision turning lathe machining,the system parameters change,and the efficiency of the active vibration-isolation system based on the traditional control strategy *** solve this problem,this paper proposes a vibration-isolation control strategy based on a genetic algorithm-back propagation neural network-PID control(GA-BP-PID),which can automatically adjust the control parameters according to the machining ***-isolation simulations and experiments based on passive vibration isolation,a PID algorithm,and the GA-BP-PID algorithm under dynamic load machining conditions were *** experimental results demonstrated that the active vibration-isolation control strategy designed in this study could effectively attenuate vibration disturbances in the external environment under dynamic load *** design is reasonable and feasible.

关键词： Ultra-precision diamond turning lathe Active vibration isolation six degrees of freedom Dynamic load Genetic algorithm-back propagation neural network-PID(GA-BP-PID)control

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Dragonfly Interaction Algorithm for Optimization of Queuing Delay in Industrial Wireless Networks

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Journal of Bionic Engineering 2024年第1期21卷 447-485页

作者： sanjay Bhardwaj da-Hye Kim Dong-seong Kim Department of IT Convergence Engineering ICT Convergence Research CenterKumoh National Institute of TechnologyGumiSouth Korea

In industrial wireless networks,data transmitted from source to destination are highly *** often leads to the queuing of the data,and poor management of the queued data results in excessive delays,increased energy consumption,and packet ***,a nature-inspired-based Dragonfly Interaction Optimization Algorithm(DMOA)is proposed for optimization of the queue delay in industrial wireless *** term“interaction”herein used is the characterization of the“flying movement”of the dragonfly towards damselflies(female dragonflies)for *** a result,interaction is represented as the flow of transmitted data packets,or traffic,from the source to the base *** includes each and every feature of dragonfly movement as well as awareness of the rival dragonflies,predators,and damselflies for the desired optimization of the queue *** features are juxtaposed as noise and interference,which are further used in the calculation of industrial wireless metrics:latency,error rate(reliability),throughput,energy efficiency,and fairness for the optimization of the queue *** analysis,convergence analysis,the Wilcoxon test,the Friedman test,and the classical as well as the 2014 IEEE Congress of Evolutionary Computation(CEC)on the benchmark functions are also used for the evaluation of DMOA in terms of its robustness and *** results demonstrate the robustness of the proposed algorithm for both classical and benchmarking functions of the IEEE CEC ***,the accuracy and efficacy of DMOA were demonstrated by means of the convergence rate,Wilcoxon testing,and ***,fairness using Jain’s index in queue delay optimization in terms of throughput and latency,along with computational complexity,is also evaluated and compared with other *** results show that DMOA exceeds other bio-inspired optimization algorithms in terms of fairness in queue delay management and average packet *** proposed a

关键词： Dragonfly damselfly Interaction Queuing delay Optimization Industrial wireless networks

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seasonal Variation of the sea surface Temperature Growth Rate of ENsO

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Advances in Atmospheric sciences 2024年第3期41卷 465-477页

作者： Xinyi XING Xianghui FANG da PANG Chaopeng JI Department of Atmospheric and Oceanic sciences and Institute of Atmospheric sciences Fudan UniversityShanghai 200438China shanghai Frontiers science Center of Atmosphere-Ocean Interaction Shanghai 200438China shanghai Key Laboratory of Ocean-land-atmosphere Boundary Dynamics and Climate Change Fudan UniversityShanghai 200438China

El Ni?o–southern Oscillation(ENsO) exhibits a distinctive phase-locking characteristic, first expressed during its onset in boreal spring, developing during summer and autumn, reaching its peak towards winter, and decaying over the next spring. several studies have demonstrated that this feature arises as a result of seasonal variation in the growth rate of ENsO as expressed by the sea surface temperature(ssT). The bias towards simulating the phase locking of ENsO by many state-of-the-art climate models is also attributed to the unrealistic depiction of the growth rate. In this study, the seasonal variation of ssT growth rate in the Ni?o-3.4 region(5°s–5°N, 120°–170°W) is estimated in detail based on the mixed layer heat budget equation and recharge oscillator model during 1981–2020. It is suggested that the consideration of a variable mixed layer depth is essential to its diagnostic process. The estimated growth rate has a remarkable seasonal cycle with minimum rates occurring in spring and maximum rates evident in autumn. More specifically, the growth rate derived from the meridional advection(surface heat flux) is positive(negative) throughout the year. Vertical diffusion generally makes a negative contribution to the evolution of growth rate and the magnitude of vertical entrainment represents the smallest contributor. Analysis indicates that the zonal advective feedback is regulated by the meridional immigration of the intertropical convergence zone, which approaches its southernmost extent in February and progresses to its northernmost location in september, and dominates the seasonal variation of the ssT growth rate.

关键词： ssT growth rate intertropical convergence zone zonal advective feedback mixed layer depth ENsO seasonal variation

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Leaf habit differentiation explains trait tradeoffs across savanna woody plants

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Forest Ecosystems 2024年第3期11卷 287-295页

作者： Yangsiding Wang da Yang German Vargas G. Guangyou Hao Jennifer s.Powers Yan Ke Qin Wang Yunbing Zhang Jiaolin Zhang CAs Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of sciences Beijing 100049China school of Biological sciences University of UtahSalt Lake CityUT 84112USA CAs Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of Ecology Evolution and BehaviorUniversity of MinnesotaSt PaulMN 55108USA

Identifying how leaf habit subdivisions link to the fast–slow and avoidance–tolerance trait tradeoffs can provide new insight into divergence in ecophysiological strategies among plant functional groups. Here, we tested a hypothesis that the differentiation across deciduous, semi-deciduous and evergreen woody species contributes to physiological trait tradeoffs in a dry-hot valley savanna. We investigated 11 photosynthetic, morphological and hydraulic traits of 24 species including 8 deciduous, 10 semi-deciduous and 6 evergreen species. Deciduous species were grouped in the fast and avoidance side associated with high values of maximum photosynthetic rates,stomatal conductance and leaf size, while evergreen species were grouped in the slow and tolerance side associated with high photosynthetic water use efficiency, leaf mass per area, sapwood density, Huber value, leaf water potential at turgor loss point and water potential causing 50% loss of stem hydraulic conductance. semideciduous species generally had intermediate trait values and represented different physiological characteristics when compared to deciduous and evergreen species. The physiological trait tradeoffs showed a close linkage to the differentiation of these three leaf habits. Our findings clearly reveal trait tradeoffs related to fast–slow and avoidance–tolerance strategies among diverse savanna plants, suggesting a syndrome in multiple ecophysiology strategies across different leaf habits.

关键词： Dry-hot habitat Gas exchange Hydraulics Phenology Tolerance Valley savanna

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