Three-layer composite ingot of 4045/3004/4045 aluminum alloys was prepared by direct-chill semi-continuous casting process,the temperature field distribution near the composite interface,macro-morphology,microstructur...Three-layer composite ingot of 4045/3004/4045 aluminum alloys was prepared by direct-chill semi-continuous casting process,the temperature field distribution near the composite interface,macro-morphology,microstructure and composition distribution of the composite interface were investigated.The results show that semi-solid layer with a certain thickness forms near the interface due to the effect of cooling plate,which ensures successful implementation of casting the composite ingot.Two different aluminum alloys are well bonded metallurgically.The mechanical properties of composite interface were measured,the tensile and shearing strengths of composite interface are 105 and 88 MPa,respectively,which proves that the composite interface is a kind of metallurgical bonding.展开更多
一、作为哲学的AI for Process(一)郭为的哲学思想1.郭为是谁郭为是谁?他是一位哲学家。顺便说,他同时还领导着神州数码。为什么说郭为是哲学家呢?因为他在著作中谈到高深的哲学,如“数据如水,奔流不息,无界融合”。他引述古希腊哲学家...一、作为哲学的AI for Process(一)郭为的哲学思想1.郭为是谁郭为是谁?他是一位哲学家。顺便说,他同时还领导着神州数码。为什么说郭为是哲学家呢?因为他在著作中谈到高深的哲学,如“数据如水,奔流不息,无界融合”。他引述古希腊哲学家赫拉克利特所说的“万物流转”,又说“你不能两次踏进同一条河流,因为新的水不断地流过你的身旁”,他所表达的意思是“世界上唯一不变的就是变化”。展开更多
Under the high-intensity ultrasonic field,AZ80 magnesium alloy was semi-continuously cast.The effects of ultrasonic intensity on the as-cast microstructures and mechanical properties were investigated.The results show...Under the high-intensity ultrasonic field,AZ80 magnesium alloy was semi-continuously cast.The effects of ultrasonic intensity on the as-cast microstructures and mechanical properties were investigated.The results show that the microstructures of the alloy cast under high-intensity ultrasonic field are fine and uniform,and the grains are equiaxed,rose-shaped or globular with an average size of 257μm.High-intensity field significantly decreases the grain size,changes the morphologies of theβ-Mg17Al12 phases and reduces their area fraction.It is also shown that a proper increase in ultrasonic intensity is helpful to obtain fine,uniform and equiaxed as-cast microstructures.The optimum ultrasonic parameters are that frequency is 20 kHz and ultrasonic intensity is 1 368 W.The mechanical tests show that the mechanical properties of the as-cast AZ80 magnesium alloy billets cast under ultrasonic field are greatly improved,and with increasing the ultrasonic intensity,the mechanical properties of the entire alloy billets are much higher and more uniform than those of the alloy without ultrasonic field.展开更多
Al-based TiC particle-reinforced composites with varying TiC concentrations were fabricated through semi-continuous casting.The effects of TiC particles on the alloys’microstructure,grain boundary segregation,and mec...Al-based TiC particle-reinforced composites with varying TiC concentrations were fabricated through semi-continuous casting.The effects of TiC particles on the alloys’microstructure,grain boundary segregation,and mechanical properties were systematically analyzed.Moreover,the mechanisms by which TiC particles contribute to grain refinement,suppression of grain boundary segregation,and enhancement of hardness and wear resistance were discussed.The results demonstrate that TiC particles act as heterogeneous nucleation sites forα-Al within the Al-Cu-Mn alloys,leading to a refinement of grain size.As the TiC particle’s content increases,the grain size of the alloy drops at first and then elevates,transitioning from coarse dendritic crystals to fine equiaxed grains.At a TiC content of 1.3wt.%,the alloy exhibits the smallest grain size,reducing from 139±42μm without TiC to 90±38μm.Beyond this concentration,grain coarsening is observed.The incorporation of TiC particles effectively mitigates Cu segregation at grain boundaries,thereby enhancing the homogeneity of the Al-Cu-Mn matrix alloys.Additionally,the addition of TiC particles promotes hardness and wear resistance.Both hardness and wear resistance exhibit an initial increase followed by a decrease with increasing TiC content from 0 to 1.8wt.%.展开更多
Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim ...Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of signifi cant,novel,and high-impact research in the fi elds of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics.展开更多
Wire arc additive manufacturing(WAAM)has emerged as a promising approach for fabricating large-scale components.However,conventional WAAM still faces challenges in optimizing microstructural evolution,minimizing addit...Wire arc additive manufacturing(WAAM)has emerged as a promising approach for fabricating large-scale components.However,conventional WAAM still faces challenges in optimizing microstructural evolution,minimizing additive-induced defects,and alleviating residual stress and deformation,all of which are critical for enhancing the mechanical performance of the manufactured parts.Integrating interlayer friction stir processing(FSP)into WAAM significantly enhances the quality of deposited materials.However,numerical simulation research focusing on elucidating the associated thermomechanical coupling mechanisms remains insufficient.A comprehensive numerical model was developed to simulate the thermomechanical coupling behavior in friction stir-assisted WAAM.The influence of post-deposition FSP on the coupled thermomechanical response of the WAAM process was analyzed quantitatively.Moreover,the residual stress distribution and deformation behavior under both single-layer and multilayer deposition conditions were investigated.Thermal analysis of different deposition layers in WAAM and friction stir-assisted WAAM was conducted.Results show that subsequent layer deposition induces partial remelting of the previously solidified layer,whereas FSP does not cause such remelting.Furthermore,thermal stress and deformation analysis confirm that interlayer FSP effectively mitigates residual stresses and distortion in WAAM components,thereby improving their structural integrity and mechanical properties.展开更多
Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental con...Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental concept drift,gradually alter the behavior or structure of processes,making their detection and localization a challenging task.Traditional process mining techniques frequently assume process stationarity and are limited in their ability to detect such drift,particularly from a control-flow perspective.The objective of this research is to develop an interpretable and robust framework capable of detecting and localizing incremental concept drift in event logs,with a specific emphasis on the structural evolution of control-flow semantics in processes.We propose DriftXMiner,a control-flow-aware hybrid framework that combines statistical,machine learning,and process model analysis techniques.The approach comprises three key components:(1)Cumulative Drift Scanner that tracks directional statistical deviations to detect early drift signals;(2)a Temporal Clustering and Drift-Aware Forest Ensemble(DAFE)to capture distributional and classification-level changes in process behavior;and(3)Petri net-based process model reconstruction,which enables the precise localization of structural drift using transition deviation metrics and replay fitness scores.Experimental validation on the BPI Challenge 2017 event log demonstrates that DriftXMiner effectively identifies and localizes gradual and incremental process drift over time.The framework achieves a detection accuracy of 92.5%,a localization precision of 90.3%,and an F1-score of 0.91,outperforming competitive baselines such as CUSUM+Histograms and ADWIN+Alpha Miner.Visual analyses further confirm that identified drift points align with transitions in control-flow models and behavioral cluster structures.DriftXMiner offers a novel and interpretable solution for incremental concept drift detection and localization in dynamic,process-aware systems.By integrating statistical signal accumulation,temporal behavior profiling,and structural process mining,the framework enables finegrained drift explanation and supports adaptive process intelligence in evolving environments.Its modular architecture supports extension to streaming data and real-time monitoring contexts.展开更多
The aging process is an inexorable fact throughout our lives and is considered a major factor in develo ping neurological dysfunctions associated with cognitive,emotional,and motor impairments.Aging-associated neurode...The aging process is an inexorable fact throughout our lives and is considered a major factor in develo ping neurological dysfunctions associated with cognitive,emotional,and motor impairments.Aging-associated neurodegenerative diseases are characterized by the progressive loss of neuronal structure and function.展开更多
The complexity of the seismicity pattern for the subduction zone along the oceanic plate triggered the outer rise events and revealed cyclic tectonic deformation conditions along the plate subduction zones.The outer r...The complexity of the seismicity pattern for the subduction zone along the oceanic plate triggered the outer rise events and revealed cyclic tectonic deformation conditions along the plate subduction zones.The outer rise earthquakes have been observed along the Sunda arc,following the estimated rupture area of the 2005 M_(W)8.6 Nias earthquakes.Here,we used kinematic waveform inversion(KIWI)to obtain the source parameters of the 14 May 2021 M_(W)6.6 event off the west coast of northern Sumatra and to define the fault plane that triggered this outer rise event.The KIWI algorithm allows two types of seismic source to be configured:the moment tensor model to describe the type of shear with six moment tensor components and the Eikonal model for the rupture of pure double-couple sources.This method was chosen for its flexibility to be applied for different sources of seismicity and also for the automated full-moment tensor solution with real-time monitoring.We used full waveform traces from 8 broadband seismic stations within 1000 km epicentral distances sourced from the Incorporated Research Institutions for Seismology(IRIS-IDA)and Geofon GFZ seismic record databases.The initial origin time and hypocenter values are obtained from the IRIS-IDA.The synthetic seismograms used in the inversion process are based on the existing regional green function database model and were accessed from the KIWI Tools Green's Function Database.The obtained scalar seismic moment value is 1.18×10^(19)N·m,equivalent to a moment magnitude M_(W)6.6.The source parameters are 140°,44°,and−99°for the strike,dip,and rake values at a centroid depth of 10.2 km,indicating that this event is a normal fault earthquake that occurred in the outer rise area.The outer rise events with normal faults typically occur at the shallow part of the plate,with nodal-plane dips predominantly in the range of 30°-60°on the weak oceanic lithosphere due to hydrothermal alteration.The stress regime around the plate subduction zone varies both temporally and spatially due to the cyclic influences of megathrust earthquakes.Tensional outer rise earthquakes tend to occur after the megathrust events.The relative timing of these events is not known due to the viscous relaxation of the down going slab and poroelastic response in the trench slope region.The occurrence of the 14 May 2021 earthquake shows the seismicity in the outer rise region in the strongly coupled Sunda arc subduction zone due to elastic bending stress within the duration of the seismic cycle.展开更多
Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening pa...Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening particles also deteriorates the processability and it is of great importance to establish accurate processing maps to guide the thermomechanical processes to enhance the formability.In this study,we performed particle swarm optimization-based back propagation artificial neural network model to predict the high temperature flow behavior of 0.25wt%Al2O3 particle-reinforced Cu alloys,and compared the accuracy with that of derived by Arrhenius-type constitutive model and back propagation artificial neural network model.To train these models,we obtained the raw data by fabricating ODS Cu alloys using the internal oxidation and reduction method,and conducting systematic hot compression tests between 400 and800℃with strain rates of 10^(-2)-10 S^(-1).At last,processing maps for ODS Cu alloys were proposed by combining processing parameters,mechanical behavior,microstructure characterization,and the modeling results achieved a coefficient of determination higher than>99%.展开更多
Overweight and obesity has been a major public health problem globally.It was estimated that more than 2.1 billion adults were affected by overweight or obese in 2021 worldwide,about one fifth of whom lived in China^(...Overweight and obesity has been a major public health problem globally.It was estimated that more than 2.1 billion adults were affected by overweight or obese in 2021 worldwide,about one fifth of whom lived in China^([1]).By 2050,the country is forecast to remain the one with the largest population of overweight and obese globally^([1]),if no effective strategies were applied on overweight/obesity control.展开更多
In this study,an automated multimodal system for detecting,classifying,and dating fruit was developed using a two-stage YOLOv11 pipeline.In the first stage,the YOLOv11 detection model locates individual date fruits in...In this study,an automated multimodal system for detecting,classifying,and dating fruit was developed using a two-stage YOLOv11 pipeline.In the first stage,the YOLOv11 detection model locates individual date fruits in real time by drawing bounding boxes around them.These bounding boxes are subsequently passed to a YOLOv11 classification model,which analyzes cropped images and assigns class labels.An additional counting module automatically tallies the detected fruits,offering a near-instantaneous estimation of quantity.The experimental results suggest high precision and recall for detection,high classification accuracy(across 15 classes),and near-perfect counting in real time.This paper presents a multi-stage pipeline for date fruit detection,classification,and automated counting,employing YOLOv11-based models to achieve high accuracy while maintaining real-time throughput.The results demonstrated that the detection precision exceeded 90%,the classification accuracy approached 92%,and the counting module correlated closely with the manual tallies.These findings confirm the potential of reducing manual labour and enhancing operational efficiency in post-harvesting processes.Future studies will include dataset expansion,user-centric interfaces,and integration with harvesting robotics.展开更多
Covert timing channels(CTC)exploit network resources to establish hidden communication pathways,posing signi cant risks to data security and policy compliance.erefore,detecting such hidden and dangerous threats remain...Covert timing channels(CTC)exploit network resources to establish hidden communication pathways,posing signi cant risks to data security and policy compliance.erefore,detecting such hidden and dangerous threats remains one of the security challenges. is paper proposes LinguTimeX,a new framework that combines natural language processing with arti cial intelligence,along with explainable Arti cial Intelligence(AI)not only to detect CTC but also to provide insights into the decision process.LinguTimeX performs multidimensional feature extraction by fusing linguistic attributes with temporal network patterns to identify covert channels precisely.LinguTimeX demonstrates strong e ectiveness in detecting CTC across multiple languages;namely English,Arabic,and Chinese.Speci cally,the LSTM and RNN models achieved F1 scores of 90%on the English dataset,89%on the Arabic dataset,and 88%on the Chinese dataset,showcasing their superior performance and ability to generalize across multiple languages. is highlights their robustness in detecting CTCs within security systems,regardless of the language or cultural context of the data.In contrast,the DeepForest model produced F1-scores ranging from 86%to 87%across the same datasets,further con rming its e ectiveness in CTC detection.Although other algorithms also showed reasonable accuracy,the LSTM and RNN models consistently outperformed them in multilingual settings,suggesting that deep learning models might be better suited for this particular problem.展开更多
With the increasing complexity of industrial automation,planetary gearboxes play a vital role in largescale equipment transmission systems,directly impacting operational efficiency and safety.Traditional maintenance s...With the increasing complexity of industrial automation,planetary gearboxes play a vital role in largescale equipment transmission systems,directly impacting operational efficiency and safety.Traditional maintenance strategies often struggle to accurately predict the degradation process of equipment,leading to excessive maintenance costs or potential failure risks.However,existing prediction methods based on statistical models are difficult to adapt to nonlinear degradation processes.To address these challenges,this study proposes a novel condition-based maintenance framework for planetary gearboxes.A comprehensive full-lifecycle degradation experiment was conducted to collect raw vibration signals,which were then processed using a temporal convolutional network autoencoder with multi-scale perception capability to extract deep temporal degradation features,enabling the collaborative extraction of longperiod meshing frequencies and short-term impact features from the vibration signals.Kernel principal component analysis was employed to fuse and normalize these features,enhancing the characterization of degradation progression.A nonlinear Wiener process was used to model the degradation trajectory,with a threshold decay function introduced to dynamically adjust maintenance strategies,and model parameters optimized through maximum likelihood estimation.Meanwhile,the maintenance strategy was optimized to minimize costs per unit time,determining the optimal maintenance timing and preventive maintenance threshold.The comprehensive indicator of degradation trends extracted by this method reaches 0.756,which is 41.2%higher than that of traditional time-domain features;the dynamic threshold strategy reduces the maintenance cost per unit time to 55.56,which is 8.9%better than that of the static threshold optimization.Experimental results demonstrate significant reductions in maintenance costs while enhancing system reliability and safety.This study realizes the organic integration of deep learning and reliability theory in the maintenance of planetary gearboxes,provides an interpretable solution for the predictive maintenance of complex mechanical systems,and promotes the development of condition-based maintenance strategies for planetary gearboxes.展开更多
Large-scale Mg-8Gd-4Y-1Zn-Mn(wt.%)alloy ingot with a diameter of 315 mm and a length of 2410 mm was prepared through semi-continuous casting.Chemical composition,microstructure and mechanical properties at different l...Large-scale Mg-8Gd-4Y-1Zn-Mn(wt.%)alloy ingot with a diameter of 315 mm and a length of 2410 mm was prepared through semi-continuous casting.Chemical composition,microstructure and mechanical properties at different locations of the samples with as-cast,T4 and T6 heat-treated states,respectively,were investigated.No obvious macro segregation has been detected in the high-quality alloy ingot.The main eutectic structures at all different locations are composed ofα-Mg,Mg3RE-type,Mg5RE-type and LPSO phases.At the edge of ingot,the unusual casting twins including 10-12 extension twins and 10-11 compression twins were observed due to the intensive internal stress.In T4 heat-treated alloy,the micro segregation was eliminated.The remained phases wereα-Mg and LPSO phase.Combined with the remarkable age-hardening response,T6 samples exhibits improved mechanical properties at ambient temperature,which derives from the dense prismaticβ'precipitates and profuse basalγ'precipitates.展开更多
Continuous and semi-continuous mining technology has become the main trend of modern surface mines in the world. According to the deposit characteristics of coal basin in China and Chinese situation,this paper discuss...Continuous and semi-continuous mining technology has become the main trend of modern surface mines in the world. According to the deposit characteristics of coal basin in China and Chinese situation,this paper discussed the new semi-continuous technology── shovel - transfer wagon-belt conveyor and its application prospect in large surface coal mines in China.展开更多
Mg-1.5Zn-0.2Zr-xCe (x=0, 0.1, 0.3, 0.5, mass fraction, %) alloys were prepared by conventional semi-continuous casting. The effect of rare earth Ce on the microstructure of Mg-1.5Zn-0.2Zr-xCe alloys was studied and th...Mg-1.5Zn-0.2Zr-xCe (x=0, 0.1, 0.3, 0.5, mass fraction, %) alloys were prepared by conventional semi-continuous casting. The effect of rare earth Ce on the microstructure of Mg-1.5Zn-0.2Zr-xCe alloys was studied and the distribution of Ce was analyzed by optical microscopy (OM), X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The results indicate that Ce element exists in the form of Mg12Ce phase and has an obvious refining effect on the microstructure of test alloys. As the Ce content increases, the grain size reduces, the grain boundaries turn thinner, and the distribution of Mg12Ce precipitates becomes more and more dispersed. The Mg-1.5Zn-0.2Zr alloy with 0.3%Ce has the best refinement effect. From center to periphery of the ingot, the amount of granular precipitates in the grain reduces. In longitudinal section of the ingot, some relative long columnar grains appear.展开更多
The microstucture, mechanical properties and fracture behaviors of semi-continuous cast Mg-8Gd- 3Y-0.5Zr （wt.%, GW83K） alloy after different heat treatments were investigated. Almost all the eutectic compounds were ...The microstucture, mechanical properties and fracture behaviors of semi-continuous cast Mg-8Gd- 3Y-0.5Zr （wt.%, GW83K） alloy after different heat treatments were investigated. Almost all the eutectic compounds were dissolved into the matrix and there was no evident grain growth after optimum solution treatment at 500 ~C for 4 h. Further ageing at low temperatures led to significant precipitation hardening, which strengthened the alloy. Peak-aged at 200℃, the alloy had the highest ultimate tensile strength （UTS） and lowest elongation at 395 MPa and 2.8%, respectively. When aged at 225℃ for 15 h, the alloy exhibited prominent mechanical performance with UTS and elongation of 363 MPa and 5.8 %, respectively. With regard to microstructure and tensile properties, the processes of 500℃, 4 h ＋ 225℃, 15 h are selected as the optimal heat treatment conditions. The alloy under different conditions shows different fracture behaviors： in the as-cast alloy, a quasi-cleavage pattern is observed; after solution treatment, the alloy exhibits a trans-granular quasi-cleavage fracture; after being peak-aged at 200℃ and 225℃, the fracture mode is a mixed mode of trans-granular and inter-granular fracture, in which the inter-granular mode is dominant in the alloy peak-aged at 200℃.展开更多
The massive consumption of fossil energy force s people to find new source s of energy.Syngas fermentation has become a hot research field as its high potential in renewable energy production and sustainable developme...The massive consumption of fossil energy force s people to find new source s of energy.Syngas fermentation has become a hot research field as its high potential in renewable energy production and sustainable development.In this study,trophic anaerobic acetogen Morella thermoacetica was successfully immobilized by calcium alginate embedding method.The ability of the immobilized cells on production of acetic acid through syngas fermentation was compared in both airlift and bubble column bioreactors.The bubble column bioreactor was selected as the better type of bioreactor.The production of acetic acid reached 32.3 g·L^(-1) in bubble column bioreactor with a space-time yield of 2.13 g·L^(-1)·d^(-1).The immobilized acetogen could be efficiently reused without significant lag period,even if exposed to air for a short time.A semi-continuous syngas fermentation was performed using immobilized cells,with an average space-time acetic acid yield of 3.20 g·L^(-1)·d^(-1).After 30 days of fermentation,no significant decrea se of the acetic acid production rate was observed.展开更多
An innovative method called semi-continuous equal channel angular extrusion （SC-ECAE） has been devel- oped to produce ullrafine grained steel by inducing severe plastic deformation. In contrast to the external force...An innovative method called semi-continuous equal channel angular extrusion （SC-ECAE） has been devel- oped to produce ullrafine grained steel by inducing severe plastic deformation. In contrast to the external forces that are exerted on specimens in traditional ECAE, the driving forces are applied on the dies in the novel SC EACE process. Commercial interslitial-free steel sheets with width of 160 mm and tbickness of 2 mm were processed re peatedly to various passes at room temperature using this method. The microstructural evolution was characterized using high-resolution electron backscatter diffraction （EBSD）, and the mechanical properties were investigated by tensile testing. The EBSD images indicated that the fraction of high angle boundaries （HABs） began to increase gradually after four passes; after six passes, elongated HAB structures with nearly submicron-scale average spacings were formed. The tensile testing results showed that strengthening was accompanied by a decrease in tensile ductili- ly, but no significant anisotropy was observed. After 10 passes, a final HAB fraction of about 90% and an overall grain size of 0.55 μm, yield strength of 638.7 MPa, an ultimate tensile strength （UTS） of 710.3 MPa, and a totfd elongation of 12.0 % were obtained.展开更多
基金Project (2005CB623707) supported by the National Basic Research Program of China
文摘Three-layer composite ingot of 4045/3004/4045 aluminum alloys was prepared by direct-chill semi-continuous casting process,the temperature field distribution near the composite interface,macro-morphology,microstructure and composition distribution of the composite interface were investigated.The results show that semi-solid layer with a certain thickness forms near the interface due to the effect of cooling plate,which ensures successful implementation of casting the composite ingot.Two different aluminum alloys are well bonded metallurgically.The mechanical properties of composite interface were measured,the tensile and shearing strengths of composite interface are 105 and 88 MPa,respectively,which proves that the composite interface is a kind of metallurgical bonding.
文摘一、作为哲学的AI for Process(一)郭为的哲学思想1.郭为是谁郭为是谁?他是一位哲学家。顺便说,他同时还领导着神州数码。为什么说郭为是哲学家呢?因为他在著作中谈到高深的哲学,如“数据如水,奔流不息,无界融合”。他引述古希腊哲学家赫拉克利特所说的“万物流转”,又说“你不能两次踏进同一条河流,因为新的水不断地流过你的身旁”,他所表达的意思是“世界上唯一不变的就是变化”。
基金Projects(2007CB613701,2007CB613702)supported by the National Basic Research Program of ChinaProjects(50974037,50904018)supported by the National Natural Science Foundation of China+1 种基金Project(NCET-08-0098)supported by New Century Excellent Talents in University of ChinaProjects(N09040902,N090209002)supported by the Special Foundation for Basic Scientific Research of Central Colleges
文摘Under the high-intensity ultrasonic field,AZ80 magnesium alloy was semi-continuously cast.The effects of ultrasonic intensity on the as-cast microstructures and mechanical properties were investigated.The results show that the microstructures of the alloy cast under high-intensity ultrasonic field are fine and uniform,and the grains are equiaxed,rose-shaped or globular with an average size of 257μm.High-intensity field significantly decreases the grain size,changes the morphologies of theβ-Mg17Al12 phases and reduces their area fraction.It is also shown that a proper increase in ultrasonic intensity is helpful to obtain fine,uniform and equiaxed as-cast microstructures.The optimum ultrasonic parameters are that frequency is 20 kHz and ultrasonic intensity is 1 368 W.The mechanical tests show that the mechanical properties of the as-cast AZ80 magnesium alloy billets cast under ultrasonic field are greatly improved,and with increasing the ultrasonic intensity,the mechanical properties of the entire alloy billets are much higher and more uniform than those of the alloy without ultrasonic field.
基金supported by the Advanced Materials-National Science and Technology Major Project(Grant No.2025ZD0611400).
文摘Al-based TiC particle-reinforced composites with varying TiC concentrations were fabricated through semi-continuous casting.The effects of TiC particles on the alloys’microstructure,grain boundary segregation,and mechanical properties were systematically analyzed.Moreover,the mechanisms by which TiC particles contribute to grain refinement,suppression of grain boundary segregation,and enhancement of hardness and wear resistance were discussed.The results demonstrate that TiC particles act as heterogeneous nucleation sites forα-Al within the Al-Cu-Mn alloys,leading to a refinement of grain size.As the TiC particle’s content increases,the grain size of the alloy drops at first and then elevates,transitioning from coarse dendritic crystals to fine equiaxed grains.At a TiC content of 1.3wt.%,the alloy exhibits the smallest grain size,reducing from 139±42μm without TiC to 90±38μm.Beyond this concentration,grain coarsening is observed.The incorporation of TiC particles effectively mitigates Cu segregation at grain boundaries,thereby enhancing the homogeneity of the Al-Cu-Mn matrix alloys.Additionally,the addition of TiC particles promotes hardness and wear resistance.Both hardness and wear resistance exhibit an initial increase followed by a decrease with increasing TiC content from 0 to 1.8wt.%.
文摘Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of signifi cant,novel,and high-impact research in the fi elds of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics.
基金National Key Research and Development Program of China(2022YFB4600902)Shandong Provincial Science Foundation for Outstanding Young Scholars(ZR2024YQ020)。
文摘Wire arc additive manufacturing(WAAM)has emerged as a promising approach for fabricating large-scale components.However,conventional WAAM still faces challenges in optimizing microstructural evolution,minimizing additive-induced defects,and alleviating residual stress and deformation,all of which are critical for enhancing the mechanical performance of the manufactured parts.Integrating interlayer friction stir processing(FSP)into WAAM significantly enhances the quality of deposited materials.However,numerical simulation research focusing on elucidating the associated thermomechanical coupling mechanisms remains insufficient.A comprehensive numerical model was developed to simulate the thermomechanical coupling behavior in friction stir-assisted WAAM.The influence of post-deposition FSP on the coupled thermomechanical response of the WAAM process was analyzed quantitatively.Moreover,the residual stress distribution and deformation behavior under both single-layer and multilayer deposition conditions were investigated.Thermal analysis of different deposition layers in WAAM and friction stir-assisted WAAM was conducted.Results show that subsequent layer deposition induces partial remelting of the previously solidified layer,whereas FSP does not cause such remelting.Furthermore,thermal stress and deformation analysis confirm that interlayer FSP effectively mitigates residual stresses and distortion in WAAM components,thereby improving their structural integrity and mechanical properties.
文摘Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental concept drift,gradually alter the behavior or structure of processes,making their detection and localization a challenging task.Traditional process mining techniques frequently assume process stationarity and are limited in their ability to detect such drift,particularly from a control-flow perspective.The objective of this research is to develop an interpretable and robust framework capable of detecting and localizing incremental concept drift in event logs,with a specific emphasis on the structural evolution of control-flow semantics in processes.We propose DriftXMiner,a control-flow-aware hybrid framework that combines statistical,machine learning,and process model analysis techniques.The approach comprises three key components:(1)Cumulative Drift Scanner that tracks directional statistical deviations to detect early drift signals;(2)a Temporal Clustering and Drift-Aware Forest Ensemble(DAFE)to capture distributional and classification-level changes in process behavior;and(3)Petri net-based process model reconstruction,which enables the precise localization of structural drift using transition deviation metrics and replay fitness scores.Experimental validation on the BPI Challenge 2017 event log demonstrates that DriftXMiner effectively identifies and localizes gradual and incremental process drift over time.The framework achieves a detection accuracy of 92.5%,a localization precision of 90.3%,and an F1-score of 0.91,outperforming competitive baselines such as CUSUM+Histograms and ADWIN+Alpha Miner.Visual analyses further confirm that identified drift points align with transitions in control-flow models and behavioral cluster structures.DriftXMiner offers a novel and interpretable solution for incremental concept drift detection and localization in dynamic,process-aware systems.By integrating statistical signal accumulation,temporal behavior profiling,and structural process mining,the framework enables finegrained drift explanation and supports adaptive process intelligence in evolving environments.Its modular architecture supports extension to streaming data and real-time monitoring contexts.
文摘The aging process is an inexorable fact throughout our lives and is considered a major factor in develo ping neurological dysfunctions associated with cognitive,emotional,and motor impairments.Aging-associated neurodegenerative diseases are characterized by the progressive loss of neuronal structure and function.
基金supported by the National Natural Science Foundation of China(Grant No.42130312)。
文摘The complexity of the seismicity pattern for the subduction zone along the oceanic plate triggered the outer rise events and revealed cyclic tectonic deformation conditions along the plate subduction zones.The outer rise earthquakes have been observed along the Sunda arc,following the estimated rupture area of the 2005 M_(W)8.6 Nias earthquakes.Here,we used kinematic waveform inversion(KIWI)to obtain the source parameters of the 14 May 2021 M_(W)6.6 event off the west coast of northern Sumatra and to define the fault plane that triggered this outer rise event.The KIWI algorithm allows two types of seismic source to be configured:the moment tensor model to describe the type of shear with six moment tensor components and the Eikonal model for the rupture of pure double-couple sources.This method was chosen for its flexibility to be applied for different sources of seismicity and also for the automated full-moment tensor solution with real-time monitoring.We used full waveform traces from 8 broadband seismic stations within 1000 km epicentral distances sourced from the Incorporated Research Institutions for Seismology(IRIS-IDA)and Geofon GFZ seismic record databases.The initial origin time and hypocenter values are obtained from the IRIS-IDA.The synthetic seismograms used in the inversion process are based on the existing regional green function database model and were accessed from the KIWI Tools Green's Function Database.The obtained scalar seismic moment value is 1.18×10^(19)N·m,equivalent to a moment magnitude M_(W)6.6.The source parameters are 140°,44°,and−99°for the strike,dip,and rake values at a centroid depth of 10.2 km,indicating that this event is a normal fault earthquake that occurred in the outer rise area.The outer rise events with normal faults typically occur at the shallow part of the plate,with nodal-plane dips predominantly in the range of 30°-60°on the weak oceanic lithosphere due to hydrothermal alteration.The stress regime around the plate subduction zone varies both temporally and spatially due to the cyclic influences of megathrust earthquakes.Tensional outer rise earthquakes tend to occur after the megathrust events.The relative timing of these events is not known due to the viscous relaxation of the down going slab and poroelastic response in the trench slope region.The occurrence of the 14 May 2021 earthquake shows the seismicity in the outer rise region in the strongly coupled Sunda arc subduction zone due to elastic bending stress within the duration of the seismic cycle.
基金financial support of the National Natural Science Foundation of China(No.52371103)the Fundamental Research Funds for the Central Universities,China(No.2242023K40028)+1 种基金the Open Research Fund of Jiangsu Key Laboratory for Advanced Metallic Materials,China(No.AMM2023B01).financial support of the Research Fund of Shihezi Key Laboratory of AluminumBased Advanced Materials,China(No.2023PT02)financial support of Guangdong Province Science and Technology Major Project,China(No.2021B0301030005)。
文摘Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening particles also deteriorates the processability and it is of great importance to establish accurate processing maps to guide the thermomechanical processes to enhance the formability.In this study,we performed particle swarm optimization-based back propagation artificial neural network model to predict the high temperature flow behavior of 0.25wt%Al2O3 particle-reinforced Cu alloys,and compared the accuracy with that of derived by Arrhenius-type constitutive model and back propagation artificial neural network model.To train these models,we obtained the raw data by fabricating ODS Cu alloys using the internal oxidation and reduction method,and conducting systematic hot compression tests between 400 and800℃with strain rates of 10^(-2)-10 S^(-1).At last,processing maps for ODS Cu alloys were proposed by combining processing parameters,mechanical behavior,microstructure characterization,and the modeling results achieved a coefficient of determination higher than>99%.
文摘Overweight and obesity has been a major public health problem globally.It was estimated that more than 2.1 billion adults were affected by overweight or obese in 2021 worldwide,about one fifth of whom lived in China^([1]).By 2050,the country is forecast to remain the one with the largest population of overweight and obese globally^([1]),if no effective strategies were applied on overweight/obesity control.
基金supported by the Deanship of Scientific Research,Vice Presidency for Graduate Studies and Scientific Research,King Faisal University,Saudi Arabia,Grant No.KFU250098.
文摘In this study,an automated multimodal system for detecting,classifying,and dating fruit was developed using a two-stage YOLOv11 pipeline.In the first stage,the YOLOv11 detection model locates individual date fruits in real time by drawing bounding boxes around them.These bounding boxes are subsequently passed to a YOLOv11 classification model,which analyzes cropped images and assigns class labels.An additional counting module automatically tallies the detected fruits,offering a near-instantaneous estimation of quantity.The experimental results suggest high precision and recall for detection,high classification accuracy(across 15 classes),and near-perfect counting in real time.This paper presents a multi-stage pipeline for date fruit detection,classification,and automated counting,employing YOLOv11-based models to achieve high accuracy while maintaining real-time throughput.The results demonstrated that the detection precision exceeded 90%,the classification accuracy approached 92%,and the counting module correlated closely with the manual tallies.These findings confirm the potential of reducing manual labour and enhancing operational efficiency in post-harvesting processes.Future studies will include dataset expansion,user-centric interfaces,and integration with harvesting robotics.
基金This study is financed by the European Union-NextGenerationEU,through the National Recovery and Resilience Plan of the Republic of Bulgaria,Project No.BG-RRP-2.013-0001.
文摘Covert timing channels(CTC)exploit network resources to establish hidden communication pathways,posing signi cant risks to data security and policy compliance.erefore,detecting such hidden and dangerous threats remains one of the security challenges. is paper proposes LinguTimeX,a new framework that combines natural language processing with arti cial intelligence,along with explainable Arti cial Intelligence(AI)not only to detect CTC but also to provide insights into the decision process.LinguTimeX performs multidimensional feature extraction by fusing linguistic attributes with temporal network patterns to identify covert channels precisely.LinguTimeX demonstrates strong e ectiveness in detecting CTC across multiple languages;namely English,Arabic,and Chinese.Speci cally,the LSTM and RNN models achieved F1 scores of 90%on the English dataset,89%on the Arabic dataset,and 88%on the Chinese dataset,showcasing their superior performance and ability to generalize across multiple languages. is highlights their robustness in detecting CTCs within security systems,regardless of the language or cultural context of the data.In contrast,the DeepForest model produced F1-scores ranging from 86%to 87%across the same datasets,further con rming its e ectiveness in CTC detection.Although other algorithms also showed reasonable accuracy,the LSTM and RNN models consistently outperformed them in multilingual settings,suggesting that deep learning models might be better suited for this particular problem.
基金funded by scientific research projects under Grant JY2024B011.
文摘With the increasing complexity of industrial automation,planetary gearboxes play a vital role in largescale equipment transmission systems,directly impacting operational efficiency and safety.Traditional maintenance strategies often struggle to accurately predict the degradation process of equipment,leading to excessive maintenance costs or potential failure risks.However,existing prediction methods based on statistical models are difficult to adapt to nonlinear degradation processes.To address these challenges,this study proposes a novel condition-based maintenance framework for planetary gearboxes.A comprehensive full-lifecycle degradation experiment was conducted to collect raw vibration signals,which were then processed using a temporal convolutional network autoencoder with multi-scale perception capability to extract deep temporal degradation features,enabling the collaborative extraction of longperiod meshing frequencies and short-term impact features from the vibration signals.Kernel principal component analysis was employed to fuse and normalize these features,enhancing the characterization of degradation progression.A nonlinear Wiener process was used to model the degradation trajectory,with a threshold decay function introduced to dynamically adjust maintenance strategies,and model parameters optimized through maximum likelihood estimation.Meanwhile,the maintenance strategy was optimized to minimize costs per unit time,determining the optimal maintenance timing and preventive maintenance threshold.The comprehensive indicator of degradation trends extracted by this method reaches 0.756,which is 41.2%higher than that of traditional time-domain features;the dynamic threshold strategy reduces the maintenance cost per unit time to 55.56,which is 8.9%better than that of the static threshold optimization.Experimental results demonstrate significant reductions in maintenance costs while enhancing system reliability and safety.This study realizes the organic integration of deep learning and reliability theory in the maintenance of planetary gearboxes,provides an interpretable solution for the predictive maintenance of complex mechanical systems,and promotes the development of condition-based maintenance strategies for planetary gearboxes.
基金financially supported by the National Key Research and Development Program of China(No.2016YFB0301100)the Natural Science Foundation Commission of China(Nos.51571044 and 51874062)+2 种基金the Chongqing foundation and advanced research project(No.cstc2019jcyjzdxmX0010)the Fundamental Research Funds for the Central Universities(Nos.2018CDGFCL0005 and 2019CDXYCL0031)the financial support from the China Scholarship Council(No.201906050113)。
文摘Large-scale Mg-8Gd-4Y-1Zn-Mn(wt.%)alloy ingot with a diameter of 315 mm and a length of 2410 mm was prepared through semi-continuous casting.Chemical composition,microstructure and mechanical properties at different locations of the samples with as-cast,T4 and T6 heat-treated states,respectively,were investigated.No obvious macro segregation has been detected in the high-quality alloy ingot.The main eutectic structures at all different locations are composed ofα-Mg,Mg3RE-type,Mg5RE-type and LPSO phases.At the edge of ingot,the unusual casting twins including 10-12 extension twins and 10-11 compression twins were observed due to the intensive internal stress.In T4 heat-treated alloy,the micro segregation was eliminated.The remained phases wereα-Mg and LPSO phase.Combined with the remarkable age-hardening response,T6 samples exhibits improved mechanical properties at ambient temperature,which derives from the dense prismaticβ'precipitates and profuse basalγ'precipitates.
文摘Continuous and semi-continuous mining technology has become the main trend of modern surface mines in the world. According to the deposit characteristics of coal basin in China and Chinese situation,this paper discussed the new semi-continuous technology── shovel - transfer wagon-belt conveyor and its application prospect in large surface coal mines in China.
基金Project(2007CB613702) supported by the National Basic Research Program of ChinaProject(CSTD2006AA4012) supported by the Key Technologies R&D Program of the Chongqing Science and Technology Commission
文摘Mg-1.5Zn-0.2Zr-xCe (x=0, 0.1, 0.3, 0.5, mass fraction, %) alloys were prepared by conventional semi-continuous casting. The effect of rare earth Ce on the microstructure of Mg-1.5Zn-0.2Zr-xCe alloys was studied and the distribution of Ce was analyzed by optical microscopy (OM), X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The results indicate that Ce element exists in the form of Mg12Ce phase and has an obvious refining effect on the microstructure of test alloys. As the Ce content increases, the grain size reduces, the grain boundaries turn thinner, and the distribution of Mg12Ce precipitates becomes more and more dispersed. The Mg-1.5Zn-0.2Zr alloy with 0.3%Ce has the best refinement effect. From center to periphery of the ingot, the amount of granular precipitates in the grain reduces. In longitudinal section of the ingot, some relative long columnar grains appear.
基金financially supported by the National Natural Science Foundation of China(51074106)the National Key Technology R&D Program of China(2011BAE22B01-5)
文摘The microstucture, mechanical properties and fracture behaviors of semi-continuous cast Mg-8Gd- 3Y-0.5Zr （wt.%, GW83K） alloy after different heat treatments were investigated. Almost all the eutectic compounds were dissolved into the matrix and there was no evident grain growth after optimum solution treatment at 500 ~C for 4 h. Further ageing at low temperatures led to significant precipitation hardening, which strengthened the alloy. Peak-aged at 200℃, the alloy had the highest ultimate tensile strength （UTS） and lowest elongation at 395 MPa and 2.8%, respectively. When aged at 225℃ for 15 h, the alloy exhibited prominent mechanical performance with UTS and elongation of 363 MPa and 5.8 %, respectively. With regard to microstructure and tensile properties, the processes of 500℃, 4 h ＋ 225℃, 15 h are selected as the optimal heat treatment conditions. The alloy under different conditions shows different fracture behaviors： in the as-cast alloy, a quasi-cleavage pattern is observed; after solution treatment, the alloy exhibits a trans-granular quasi-cleavage fracture; after being peak-aged at 200℃ and 225℃, the fracture mode is a mixed mode of trans-granular and inter-granular fracture, in which the inter-granular mode is dominant in the alloy peak-aged at 200℃.
基金supported by the National Key Research and Development Program of China (2019YFA0905000)the National Natural Science Foundation of China (21536004, 21922804, 21776085, and 21871085)the Fundamental Research Funds for the Central Universities (22221818014)。
文摘The massive consumption of fossil energy force s people to find new source s of energy.Syngas fermentation has become a hot research field as its high potential in renewable energy production and sustainable development.In this study,trophic anaerobic acetogen Morella thermoacetica was successfully immobilized by calcium alginate embedding method.The ability of the immobilized cells on production of acetic acid through syngas fermentation was compared in both airlift and bubble column bioreactors.The bubble column bioreactor was selected as the better type of bioreactor.The production of acetic acid reached 32.3 g·L^(-1) in bubble column bioreactor with a space-time yield of 2.13 g·L^(-1)·d^(-1).The immobilized acetogen could be efficiently reused without significant lag period,even if exposed to air for a short time.A semi-continuous syngas fermentation was performed using immobilized cells,with an average space-time acetic acid yield of 3.20 g·L^(-1)·d^(-1).After 30 days of fermentation,no significant decrea se of the acetic acid production rate was observed.
文摘An innovative method called semi-continuous equal channel angular extrusion （SC-ECAE） has been devel- oped to produce ullrafine grained steel by inducing severe plastic deformation. In contrast to the external forces that are exerted on specimens in traditional ECAE, the driving forces are applied on the dies in the novel SC EACE process. Commercial interslitial-free steel sheets with width of 160 mm and tbickness of 2 mm were processed re peatedly to various passes at room temperature using this method. The microstructural evolution was characterized using high-resolution electron backscatter diffraction （EBSD）, and the mechanical properties were investigated by tensile testing. The EBSD images indicated that the fraction of high angle boundaries （HABs） began to increase gradually after four passes; after six passes, elongated HAB structures with nearly submicron-scale average spacings were formed. The tensile testing results showed that strengthening was accompanied by a decrease in tensile ductili- ly, but no significant anisotropy was observed. After 10 passes, a final HAB fraction of about 90% and an overall grain size of 0.55 μm, yield strength of 638.7 MPa, an ultimate tensile strength （UTS） of 710.3 MPa, and a totfd elongation of 12.0 % were obtained.
