Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a nove...Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system emergence.To address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating laws.Finally,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”.展开更多
In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relat...In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relationship and functions of the integrated database,the intelligent thermal control system and the efficient liquid cooling system in the ATMS are elaborated upon.For the complex thermal field regulation system and extreme space thermal environment,a modular simulation and thermal field planning method are proposed,and the feasibility of the planning algorithm is verified by numerical simulation.A solar array liquid cooling system is developed,and the system simulation results indicate that the temperatures of the solar arrays meet the requirements as the spacecraft flies by perihelion and aphelion.The advanced thermal management study supports the development of the SCOPE program and provides a reference for the thermal management in other deep-space exploration programs.展开更多
To investigate the complex macro-mechanical properties of coal from a micro-mechanical perspective,we have conducted a series of micro-mechanical experiments on coal using a nano-indentation instrument.These experimen...To investigate the complex macro-mechanical properties of coal from a micro-mechanical perspective,we have conducted a series of micro-mechanical experiments on coal using a nano-indentation instrument.These experiments were conducted under both dynamic and static loading conditions,allowing us to gather the micro-mechanical parameters of coal for further analysis of its micro-mechanical heterogeneity using the box counting statistical method and the Weibull model.The research findings indicate that the load–displacement curves of the coal mass under the two different loading modes exhibit noticeable discreteness.This can be attributed to the stress concentration phenomenon caused by variations in the mechanical properties of the micro-units during the loading process of the coal mass.Consequently,there are significant fluctuations in the micro-mechanical parameters of the coal mass.Moreover,the mechanical heterogeneity of the coal at the nanoscale was confirmed based on the calculation results of the standard deviation coefficient and Weibull modulus of the coal body’s micromechanical parameters.These results reveal the influence of microstructural defects and minerals on the uniformity of the stress field distribution within the loaded coal body,as well as on the ductility characteristics of the micro-defect structure.Furthermore,there is a pronounced heterogeneity in the micromechanical parameters.Furthermore,we have established a relationship between the macro and micro elastic modulus of coal by applying the Mori-Tanaka homogenization method.This relationship holds great significance for revealing the micro-mechanical failure mechanism of coal.展开更多
Students'demand for online learning has exploded during the post-COvID-19 pandemic era.However,due to their poor learning experience,students'dropout rate and learning performance of online learning are not al...Students'demand for online learning has exploded during the post-COvID-19 pandemic era.However,due to their poor learning experience,students'dropout rate and learning performance of online learning are not always satisfactory.The technical advantages of Beyond Fifth Generation(B5G)can guarantee a good multimedia Quality of Experience(QoE).As a special case of multimedia services,online learning takes into account both the usability of the service and the cognitive development of the users.Factors that affect the Quality of Online Learning Experience(OL-QoE)become more complicated.To get over this dilemma,we propose a systematic scheme by integrating big data,Machine Learning(ML)technologies,and educational psychology theory.Specifically,we first formulate a general definition of OL-QoE by data analysis and experimental verification.This formula considers both the subjective and objective factors(i.e.,video watching ratio and test scores)that most affect OLQoE.Then,we induce an extended layer to the classic Broad Learning System(BLS)to construct an Extended Broad Learning System(EBLS)for the students'OL-QoE prediction.Since the extended layer can increase the width of the BLS model and reduce the redundant nodes of BLS,the proposed EBLS can achieve a trade-off between the prediction accuracy and computation complexity.Finally,we provide a series of early intervention suggestions for different types of students according to their predicted OL-QoE values.Through timely interventions,their OL-QoE and learning performance can be improved.Experimental results verify the effectiveness oftheproposed scheme.展开更多
Geophysical fluid dynamics(GFD)is an interdisciplinary field that studies the large-scale motion of fluids in the natural world.With a wide range of applications such as weather forecasts and climate prediction,GFD em...Geophysical fluid dynamics(GFD)is an interdisciplinary field that studies the large-scale motion of fluids in the natural world.With a wide range of applications such as weather forecasts and climate prediction,GFD employs various research approaches including in-situ observations,satellite measurements,numerical simulations,theoretical analysis,artificial intelligence,and physical model experiments in laboratory.Among these approaches,rotating tank experiments provide a valuable tool for simulating naturally-occurring fluid motions in laboratories.With proportional scaling and proper techniques,scientists can reproduce multi-scale physical processes of stratified fluids in the rotation system,which allows for the simulation of essential characteristics of fluid motions in the atmosphere and oceans.In this review,rotating tanks of various scales in the world are introduced,as these tanks have been actively used to explore fundamental scientific questions in ocean and atmosphere dynamics.To illustrate the GFD experiments,three representative cases are presented to demonstrate the frontier achievements in the the GFD study by using rotating tank experiments:mesoscale eddies in the ocean,convection processes,and plume dynamics.Detailed references for the experimental procedures are provided.Future studies are encouraged to further explore the utilization of rotating tanks with improvements in experimental design and integration of other research methods.This is a promising direction of GFD to help enhance our understanding of the complex nature of fluid motions in the natural world and to address the challenges posed by global environmental changes.展开更多
Fine grains migration is a primary cause of landslides and debris flows.This study investigates the effect of fine-grain migration on slope failure through flume experiments,focusing on the spatiotemporal characterist...Fine grains migration is a primary cause of landslides and debris flows.This study investigates the effect of fine-grain migration on slope failure through flume experiments,focusing on the spatiotemporal characteristics and mechanisms of slope stability.A series of artificial rainfall flume experiments with varying rainfall intensities and slopes were conducted using soil samples collected from Wei Jia Gully.The experiments monitored pore-water pressure,grain migration,and failure sequences.Grain-size distribution parameters(μand Dc)were analyzed to understand the migration path and accumulation of fine grains.The experiments reveal that fine-grain migration significantly alters soil structure,leading to random blockage and interconnection of internal pore channels.These changes result in fluctuating pore-water pressure distributions and uneven fine-grain accumulation,critical factors in slope stability.Slope failures occur randomly and intermittently,influenced by fine-grain content in runoff and resulting pore-water pressure variations.This study highlights that fine-grain migration plays a vital role in slope stability,with significant implications for predicting and mitigating slope failures.The stochastic nature of fine-grain migration and its impact on soil properties should be incorporated into predictive models to enhance their accuracy and reliability.展开更多
The analysis of Greenhouse Effect experiments in the public domain indicated that the lab tests were primarily centered around illustrating the mechanics of conventional greenhouses. They used high-energy visible ligh...The analysis of Greenhouse Effect experiments in the public domain indicated that the lab tests were primarily centered around illustrating the mechanics of conventional greenhouses. They used high-energy visible light (such as sunlight), rather than addressing the Greenhouse Effect, which involves low-energy infrared radiation emitted by the Earth’s surface. Studies with argon, a non-greenhouse gas with similar density to CO2, showed thermal heat transfer as the dominant factor in the temperature profiles, with radiation absorption being undetected. The same conclusion was drawn by another study, which measured infrared back radiation. Experiments using exaggerated CO2 concentrations inadvertently illustrated the principle of the Popper Falsification Test by disproving the Greenhouse Effect applicable to CO2 within the troposphere. A straightforward kitchen test showed that a microwave oven cannot be used as a model for the Greenhouse Effect.展开更多
From 2019 to 2021,China Seismic Experimental Site has built twelve 300 m deep well multi-measurement comprehensive observation stations in the cross-fault area of the Aninghe-Zemuhe fault zone,integrating BBVS120 very...From 2019 to 2021,China Seismic Experimental Site has built twelve 300 m deep well multi-measurement comprehensive observation stations in the cross-fault area of the Aninghe-Zemuhe fault zone,integrating BBVS120 very broadband borehole seismometer,RZB four-gauge borehole strainmeter and geothermometer with resolution up to 0.0001℃.The borehole diameter is 150 mm and the inner diameter of the sleeve is 130 mm.The multi-item integrated observation system is divided into two parts:underground and surface.The downhole part is mainly composed of sensor and power supply signal isolation.展开更多
This study presents the ballistic limit velocity of small caliber projectiles against SS400 steel plate derived from live-fire ballistic experiments. Four different small caliber projectiles were tested against SS400 ...This study presents the ballistic limit velocity of small caliber projectiles against SS400 steel plate derived from live-fire ballistic experiments. Four different small caliber projectiles were tested against SS400 steel plates of 9 mm, 10 mm, and 12 mm thicknesses. The ballistic limit velocity was calculated using two standard methods, MIL-STD-662F and NIJ-STD-0101.06, and additionally using a support vector machine algorithm. The results show a linear relationship between the plate thickness and ballistic limit velocity. Further, the relative penetration performance among five different small caliber projectiles was analyzed using the Penetration Performance Ratio(PPR) introduced in this study, which suggests the potential of PPR to predict the ballistic limit velocity of other untested materials and/or different projectiles.展开更多
Physical chemistry experiments are an important branch of chemical experiments.In view of problems and shortcomings in physical chemistry experiment teaching of food quality and safety major in Chengdu University,the ...Physical chemistry experiments are an important branch of chemical experiments.In view of problems and shortcomings in physical chemistry experiment teaching of food quality and safety major in Chengdu University,the teaching methods of physical chemistry experiment course of food quality and safety major were explored and practiced,aiming to arouse students enthusiasm for experiments and cultivate their ability of independent learning,comprehensive thinking and independent problem solving.展开更多
Background:Primary biliary cholangitis(PBC)is a chronic biliary autoimmune liver disease characterized by intrahepatic cholestasis.Swertia mussotii Franch.(SMF)is a Tibetan medicine with hepatoprotective and anti-infl...Background:Primary biliary cholangitis(PBC)is a chronic biliary autoimmune liver disease characterized by intrahepatic cholestasis.Swertia mussotii Franch.(SMF)is a Tibetan medicine with hepatoprotective and anti-inflammatory activities.In this study,the therapeutic effect and potential mechanisms of SMF on PBC were investigated by bioinformatics analysis and in vitro experimental validation,with the aim of promoting the progress of SMF and PBC research.Methods:We first explored the therapeutic effects and key targets of SMF on PBC using a network pharmacology approach,further screened the core targets using the GSE79850 dataset,and finally validated the results using molecular docking techniques and in vitro experiments.Results:By bioinformatics analysis,we identified core targets of SMF for PBC treatment(STAT3,JAK2,TNF-α,and IL-1β)and important signaling pathways:JAK-STAT,TNF,and PI3K-AKT.The molecular docking results showed that the significant components of SMF had good binding properties to the core targets.In vitro experiments showed that SMF extracts improved the extent of epithelial-mesenchymal transition in human intrahepatic biliary epithelial cells and had a significant reversal effect on epithelial-mesenchymal transition process markers and potential targets in PBC.Conclusion:SMF may exert its therapeutic effects on PBC by acting on important targets such as STAT3,JAK2,TNF-α,IL-1β,Vimentin,and E-cadherin and the pathways in which they are involved.展开更多
This paper explores the integration of simulation technology in Engineering Mechanics(EM)teaching in vocational colleges.A case study was conducted using the tensile test as an example,and digital resources,such as co...This paper explores the integration of simulation technology in Engineering Mechanics(EM)teaching in vocational colleges.A case study was conducted using the tensile test as an example,and digital resources,such as colored Mises stress nephograms,were obtained.These resources were integrated into the original curriculum to conduct teaching experiments.The results show that the use of digital resources significantly improved the quality of teaching in EM.The integration of simulation technology in EM teaching provides a promising direction for the improvement of vocational education and the cultivation of high-quality skilled talents.The development and application of more simulation-based teaching cases should be studied by scholars.展开更多
Globally,many lakes are drying up,leaving exposed lakebeds where wind erosion releases dust and sand rich in salt and harmful heavy metals into the atmosphere.Therefore,understanding the characteristics and spatial di...Globally,many lakes are drying up,leaving exposed lakebeds where wind erosion releases dust and sand rich in salt and harmful heavy metals into the atmosphere.Therefore,understanding the characteristics and spatial distribution of playa surface crusts is important to recognize the manifestation of salt dust storms.The objective of this study was to explore the playa surface crust types as well as their spatial distribution and evolution of Qehan Lake in Inner Mongolia Autonomous Region,China to understand the salt dust release potential of different types of playa surface crusts.Various crust characteristics were investigated by field sampling in Qehan Lake,and playa surface crusts were further divided into five types:vegetated areas,salt crusts,clay flats,curly crusts,and margins.It should be noted that curly crusts were distributed in clay flats and covered only a small area in Qehan Lake.The spatial distribution characteristics of playa surface crust types were obtained by supervised classification of remote sensing images,and the salt dust release potential of crusts was explored by the wind tunnel experiments.The field investigation of Qehan Lake revealed that playa surface crust types had a circum-lake band distribution from the inside to the outside of this lake,which were successively vegetated areas,clay flats,salt crusts,and margins.The spatial distribution patterns of playa surface crust types were mainly controlled by the hydrodynamics of the playa,soil texture,and groundwater.There was a significant negative correlation between crust thickness and electrical conductivity.The results of the wind tunnel experiments showed that the initial threshold of friction wind velocity for the salt dust release was higher in clay flats(0.7–0.8 m/s)than in salt crusts(0.5–0.6 m/s).Moreover,the particle leap impact processes occurring under natural conditions may reduce this threshold value.Salinity was the main factor controlling the difference in the initial threshold of friction wind velocity for the salt dust release of clay flats and salt crusts.This study provides a scientific reference for understanding how salt dust is released from a lakebed,which may be used for ecological restoration of dry salt lakes.展开更多
[Objectives]The quality of pear wine is directly affected by parameter control in the production process, especially in the fermentation stage. The fermentation parameters of pear wine were controlled by studying the ...[Objectives]The quality of pear wine is directly affected by parameter control in the production process, especially in the fermentation stage. The fermentation parameters of pear wine were controlled by studying the effects of fermentation parameters on the product, in order to optimize the fermentation parameters. [Methods]The fermentation conditions of pear wine were optimized by single factor experiments and an orthogonal experiment. [Results] The optimum fermentation conditions of pear wine were nitrogen source 1.0 g/L, fermentation temperature 20 ℃, and pH of fermentation liquid 4.3. The pear wine brewed was full, mellow and harmonious, and had a unique style. The ethanol content of the pear wine was 12.33 through physical and chemical analysis. [Conclusions] This study provides theoretical basis and technical support for the industrial production and promotion of pear wine.展开更多
For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is compulsory.Thus,process analytical technology(PAT)that allows deeper insight into the proc...For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is compulsory.Thus,process analytical technology(PAT)that allows deeper insight into the process and results in a mathematical description of the process behavior as a simple function based on the most important process factors can help to achieve higher production efficiency and quality.The present study aims at characterizing a well-known industrial process,the transesterification reaction of rapeseed oil with methanol to produce fatty acid methyl esters(FAME)for usage as biodiesel in a continuous micro reactor set-up.To this end,a design of experiment approach is applied,where the effects of two process factors,the molar ratio and the total flow rate of the reactants,are investigated.The optimized process target response is the FAME mass fraction in the purified nonpolar phase of the product as a measure of reaction yield.The quantification is performed using attenuated total reflection infrared spectroscopy in combination with partial least squares regression.The data retrieved during the conduction of the DoE experimental plan were used for statistical analysis.A non-linear model indicating a synergistic interaction between the studied factors describes the reactor behavior with a high coefficient of determination(R^(2))of 0.9608.Thus,we applied a PAT approach to generate further insight into this established industrial process.展开更多
Objective:Based on network pharmacology and molecular docking technology to explore the mechanism of Professor Cao Enze's application of Panax notoginseng in the treatment of membranous nephropathy.Methods:TCMSP d...Objective:Based on network pharmacology and molecular docking technology to explore the mechanism of Professor Cao Enze's application of Panax notoginseng in the treatment of membranous nephropathy.Methods:TCMSP database was used to obtain the effective components and corresponding target information of Panax notoginseng,and Gene Cards database was used to obtain the disease target genes of membranous nephropathy.The intersection targets of the two were taken and the Venn diagram was drawn.The STRING database was used to obtain the protein interaction relationship,and the PPI network diagram was constructed by Cytoscape 3.9.1 software to screen out the core targets of Panax notoginseng in the treatment of membranous nephropathy.GO function and KEGG pathway enrichment analysis were performed using the David database to obtain the potential pathway of Panax notoginseng in the treatment of membranous nephropathy.Finally,Autodock software was used to verify the molecular docking of the main active components of the drug with the core targets.Results:A total of 7 effective components such as quercetin,ginsenoside rh2,Mandenol and Stigmasterol were retrieved,and 127 potential targets of Panax notoginseng in the treatment of membranous nephropathy were screened out.By PPI network topology analysis,23 core targets such as JUN,TP53,RELA,AKT1 and MAPK1 were screened out.GO functional enrichment analysis contained 703 biological processes,55 cell components and 121 molecular functions,and KEGG signal pathway enrichment analysis enriched 171 signal pathways.The results of molecular docking showed that there was a strong binding ability between the main core targets and the main components of Panax notoginseng.Conclusion:Through network pharmacology,it is concluded that Panax notoginseng treats membranous nephropathy through multiple targets and multiple pathways,which provides a theoretical basis for subsequent basic research.展开更多
This article investigates the dynamic relationship between technology and AI(artificial intelligence)and the role that societal requirements play in pushing AI research and adoption.Technology has advanced dramaticall...This article investigates the dynamic relationship between technology and AI(artificial intelligence)and the role that societal requirements play in pushing AI research and adoption.Technology has advanced dramatically throughout the years,providing the groundwork for the rise of AI.AI systems have achieved incredible feats in various disciplines thanks to advancements in computer power,data availability,and complex algorithms.On the other hand,society’s needs for efficiency,enhanced healthcare,environmental sustainability,and personalized experiences have worked as powerful accelerators for AI’s progress.This article digs into how technology empowers AI and how societal needs dictate its progress,emphasizing their symbiotic relationship.The findings underline the significance of responsible AI research,which considers both technological prowess and ethical issues,to ensure that AI continues to serve the greater good.展开更多
As critical measures to educate and cultivate people’s morality,“Ideology and Politics of Course”has gradually become the focus in actual undergraduate education research in universities.Targeting the single ideolo...As critical measures to educate and cultivate people’s morality,“Ideology and Politics of Course”has gradually become the focus in actual undergraduate education research in universities.Targeting the single ideological and political education mode and students’lack of interest in experimental courses,this paper,through various links,including pre-class preview,in-class teaching,and after-class data analysis,takes the common emitter single tube amplifier experiment as an example to organically integrate the excavated ideological and political elements with practical operation and carry out teaching case design and practice;realize the improvement of students’learning initiative and problem-analysis ability;and achieve the purpose of cultivating people throughout the whole process and in a comprehensive direction.展开更多
基金the National Key Research and Development Program of China(2021YFF0900800)the National Natural Science Foundation of China(61972276,62206116,62032016)+2 种基金the New Liberal Arts Reform and Practice Project of National Ministry of Education(2021170002)the Open Research Fund of the State Key Laboratory for Management and Control of Complex Systems(20210101)Tianjin University Talent Innovation Reward Program for Literature and Science Graduate Student(C1-2022-010)。
文摘Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system emergence.To address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating laws.Finally,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”.
文摘In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relationship and functions of the integrated database,the intelligent thermal control system and the efficient liquid cooling system in the ATMS are elaborated upon.For the complex thermal field regulation system and extreme space thermal environment,a modular simulation and thermal field planning method are proposed,and the feasibility of the planning algorithm is verified by numerical simulation.A solar array liquid cooling system is developed,and the system simulation results indicate that the temperatures of the solar arrays meet the requirements as the spacecraft flies by perihelion and aphelion.The advanced thermal management study supports the development of the SCOPE program and provides a reference for the thermal management in other deep-space exploration programs.
基金Projects(U23B2093,52274245)supported by the National Natural Science Foundation of ChinaProject(KFJJ22-15M)supported by the Opening Project of State Key Laboratory of Explosion Science and Technology,China。
文摘To investigate the complex macro-mechanical properties of coal from a micro-mechanical perspective,we have conducted a series of micro-mechanical experiments on coal using a nano-indentation instrument.These experiments were conducted under both dynamic and static loading conditions,allowing us to gather the micro-mechanical parameters of coal for further analysis of its micro-mechanical heterogeneity using the box counting statistical method and the Weibull model.The research findings indicate that the load–displacement curves of the coal mass under the two different loading modes exhibit noticeable discreteness.This can be attributed to the stress concentration phenomenon caused by variations in the mechanical properties of the micro-units during the loading process of the coal mass.Consequently,there are significant fluctuations in the micro-mechanical parameters of the coal mass.Moreover,the mechanical heterogeneity of the coal at the nanoscale was confirmed based on the calculation results of the standard deviation coefficient and Weibull modulus of the coal body’s micromechanical parameters.These results reveal the influence of microstructural defects and minerals on the uniformity of the stress field distribution within the loaded coal body,as well as on the ductility characteristics of the micro-defect structure.Furthermore,there is a pronounced heterogeneity in the micromechanical parameters.Furthermore,we have established a relationship between the macro and micro elastic modulus of coal by applying the Mori-Tanaka homogenization method.This relationship holds great significance for revealing the micro-mechanical failure mechanism of coal.
基金supported by Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX20_0733)Education Reform Foundation of Jiangsu Province(Grant No.2021JSJG364)+1 种基金Key Education Reform Foundation of NJUPT(Grant No.JG00220JX02,JG00218JX03,JG00215JX01,JG00214JX52)the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘Students'demand for online learning has exploded during the post-COvID-19 pandemic era.However,due to their poor learning experience,students'dropout rate and learning performance of online learning are not always satisfactory.The technical advantages of Beyond Fifth Generation(B5G)can guarantee a good multimedia Quality of Experience(QoE).As a special case of multimedia services,online learning takes into account both the usability of the service and the cognitive development of the users.Factors that affect the Quality of Online Learning Experience(OL-QoE)become more complicated.To get over this dilemma,we propose a systematic scheme by integrating big data,Machine Learning(ML)technologies,and educational psychology theory.Specifically,we first formulate a general definition of OL-QoE by data analysis and experimental verification.This formula considers both the subjective and objective factors(i.e.,video watching ratio and test scores)that most affect OLQoE.Then,we induce an extended layer to the classic Broad Learning System(BLS)to construct an Extended Broad Learning System(EBLS)for the students'OL-QoE prediction.Since the extended layer can increase the width of the BLS model and reduce the redundant nodes of BLS,the proposed EBLS can achieve a trade-off between the prediction accuracy and computation complexity.Finally,we provide a series of early intervention suggestions for different types of students according to their predicted OL-QoE values.Through timely interventions,their OL-QoE and learning performance can be improved.Experimental results verify the effectiveness oftheproposed scheme.
基金Supported by the National Key Research and Development Program of China(Nos.2017YFA0604100,2016YFC1402004,2017YFC1404200)the Program for Innovation Research and Entrepreneurship Team in Jiangsu Provincethe National Natural Science Foundation of China(Nos.41476022,41490643)。
文摘Geophysical fluid dynamics(GFD)is an interdisciplinary field that studies the large-scale motion of fluids in the natural world.With a wide range of applications such as weather forecasts and climate prediction,GFD employs various research approaches including in-situ observations,satellite measurements,numerical simulations,theoretical analysis,artificial intelligence,and physical model experiments in laboratory.Among these approaches,rotating tank experiments provide a valuable tool for simulating naturally-occurring fluid motions in laboratories.With proportional scaling and proper techniques,scientists can reproduce multi-scale physical processes of stratified fluids in the rotation system,which allows for the simulation of essential characteristics of fluid motions in the atmosphere and oceans.In this review,rotating tanks of various scales in the world are introduced,as these tanks have been actively used to explore fundamental scientific questions in ocean and atmosphere dynamics.To illustrate the GFD experiments,three representative cases are presented to demonstrate the frontier achievements in the the GFD study by using rotating tank experiments:mesoscale eddies in the ocean,convection processes,and plume dynamics.Detailed references for the experimental procedures are provided.Future studies are encouraged to further explore the utilization of rotating tanks with improvements in experimental design and integration of other research methods.This is a promising direction of GFD to help enhance our understanding of the complex nature of fluid motions in the natural world and to address the challenges posed by global environmental changes.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA23090202)the Key Science and Technology Projects of Transportation Industry(Grant No.2021-MS4-104)the National Key Research and Development Program of China(Grant No.2019YFC1509900).
文摘Fine grains migration is a primary cause of landslides and debris flows.This study investigates the effect of fine-grain migration on slope failure through flume experiments,focusing on the spatiotemporal characteristics and mechanisms of slope stability.A series of artificial rainfall flume experiments with varying rainfall intensities and slopes were conducted using soil samples collected from Wei Jia Gully.The experiments monitored pore-water pressure,grain migration,and failure sequences.Grain-size distribution parameters(μand Dc)were analyzed to understand the migration path and accumulation of fine grains.The experiments reveal that fine-grain migration significantly alters soil structure,leading to random blockage and interconnection of internal pore channels.These changes result in fluctuating pore-water pressure distributions and uneven fine-grain accumulation,critical factors in slope stability.Slope failures occur randomly and intermittently,influenced by fine-grain content in runoff and resulting pore-water pressure variations.This study highlights that fine-grain migration plays a vital role in slope stability,with significant implications for predicting and mitigating slope failures.The stochastic nature of fine-grain migration and its impact on soil properties should be incorporated into predictive models to enhance their accuracy and reliability.
文摘The analysis of Greenhouse Effect experiments in the public domain indicated that the lab tests were primarily centered around illustrating the mechanics of conventional greenhouses. They used high-energy visible light (such as sunlight), rather than addressing the Greenhouse Effect, which involves low-energy infrared radiation emitted by the Earth’s surface. Studies with argon, a non-greenhouse gas with similar density to CO2, showed thermal heat transfer as the dominant factor in the temperature profiles, with radiation absorption being undetected. The same conclusion was drawn by another study, which measured infrared back radiation. Experiments using exaggerated CO2 concentrations inadvertently illustrated the principle of the Popper Falsification Test by disproving the Greenhouse Effect applicable to CO2 within the troposphere. A straightforward kitchen test showed that a microwave oven cannot be used as a model for the Greenhouse Effect.
基金funded by National Key Research and Development Project(Grant No.2022YFC2204301)the Special Fund of the Institute of Earthquake Forecasting,China Earthquake Administration(Grant No.CEAIEF2022030105).
文摘From 2019 to 2021,China Seismic Experimental Site has built twelve 300 m deep well multi-measurement comprehensive observation stations in the cross-fault area of the Aninghe-Zemuhe fault zone,integrating BBVS120 very broadband borehole seismometer,RZB four-gauge borehole strainmeter and geothermometer with resolution up to 0.0001℃.The borehole diameter is 150 mm and the inner diameter of the sleeve is 130 mm.The multi-item integrated observation system is divided into two parts:underground and surface.The downhole part is mainly composed of sensor and power supply signal isolation.
文摘This study presents the ballistic limit velocity of small caliber projectiles against SS400 steel plate derived from live-fire ballistic experiments. Four different small caliber projectiles were tested against SS400 steel plates of 9 mm, 10 mm, and 12 mm thicknesses. The ballistic limit velocity was calculated using two standard methods, MIL-STD-662F and NIJ-STD-0101.06, and additionally using a support vector machine algorithm. The results show a linear relationship between the plate thickness and ballistic limit velocity. Further, the relative penetration performance among five different small caliber projectiles was analyzed using the Penetration Performance Ratio(PPR) introduced in this study, which suggests the potential of PPR to predict the ballistic limit velocity of other untested materials and/or different projectiles.
文摘Physical chemistry experiments are an important branch of chemical experiments.In view of problems and shortcomings in physical chemistry experiment teaching of food quality and safety major in Chengdu University,the teaching methods of physical chemistry experiment course of food quality and safety major were explored and practiced,aiming to arouse students enthusiasm for experiments and cultivate their ability of independent learning,comprehensive thinking and independent problem solving.
基金supported by the Key project of Chinese Academy of Sciences(Grant No.ZDRW-ZS-2020-2)Innovation Platform Program of Qinghai Province(2021-ZJ-T02),Key Laboratory Project of Qinghai Province(2022-ZJ-Y05)+1 种基金the Natural Science Foundation of China(Grant No.82171863)China Postdoctoral Science Foundation funded project(2021M701642).
文摘Background:Primary biliary cholangitis(PBC)is a chronic biliary autoimmune liver disease characterized by intrahepatic cholestasis.Swertia mussotii Franch.(SMF)is a Tibetan medicine with hepatoprotective and anti-inflammatory activities.In this study,the therapeutic effect and potential mechanisms of SMF on PBC were investigated by bioinformatics analysis and in vitro experimental validation,with the aim of promoting the progress of SMF and PBC research.Methods:We first explored the therapeutic effects and key targets of SMF on PBC using a network pharmacology approach,further screened the core targets using the GSE79850 dataset,and finally validated the results using molecular docking techniques and in vitro experiments.Results:By bioinformatics analysis,we identified core targets of SMF for PBC treatment(STAT3,JAK2,TNF-α,and IL-1β)and important signaling pathways:JAK-STAT,TNF,and PI3K-AKT.The molecular docking results showed that the significant components of SMF had good binding properties to the core targets.In vitro experiments showed that SMF extracts improved the extent of epithelial-mesenchymal transition in human intrahepatic biliary epithelial cells and had a significant reversal effect on epithelial-mesenchymal transition process markers and potential targets in PBC.Conclusion:SMF may exert its therapeutic effects on PBC by acting on important targets such as STAT3,JAK2,TNF-α,IL-1β,Vimentin,and E-cadherin and the pathways in which they are involved.
基金Science and Technology Key Project of Beijing Polytechnic(Project number:2024X008-KXZ)。
文摘This paper explores the integration of simulation technology in Engineering Mechanics(EM)teaching in vocational colleges.A case study was conducted using the tensile test as an example,and digital resources,such as colored Mises stress nephograms,were obtained.These resources were integrated into the original curriculum to conduct teaching experiments.The results show that the use of digital resources significantly improved the quality of teaching in EM.The integration of simulation technology in EM teaching provides a promising direction for the improvement of vocational education and the cultivation of high-quality skilled talents.The development and application of more simulation-based teaching cases should be studied by scholars.
基金funded by the National Natural Science Foundation of China (42067013, 41571090)
文摘Globally,many lakes are drying up,leaving exposed lakebeds where wind erosion releases dust and sand rich in salt and harmful heavy metals into the atmosphere.Therefore,understanding the characteristics and spatial distribution of playa surface crusts is important to recognize the manifestation of salt dust storms.The objective of this study was to explore the playa surface crust types as well as their spatial distribution and evolution of Qehan Lake in Inner Mongolia Autonomous Region,China to understand the salt dust release potential of different types of playa surface crusts.Various crust characteristics were investigated by field sampling in Qehan Lake,and playa surface crusts were further divided into five types:vegetated areas,salt crusts,clay flats,curly crusts,and margins.It should be noted that curly crusts were distributed in clay flats and covered only a small area in Qehan Lake.The spatial distribution characteristics of playa surface crust types were obtained by supervised classification of remote sensing images,and the salt dust release potential of crusts was explored by the wind tunnel experiments.The field investigation of Qehan Lake revealed that playa surface crust types had a circum-lake band distribution from the inside to the outside of this lake,which were successively vegetated areas,clay flats,salt crusts,and margins.The spatial distribution patterns of playa surface crust types were mainly controlled by the hydrodynamics of the playa,soil texture,and groundwater.There was a significant negative correlation between crust thickness and electrical conductivity.The results of the wind tunnel experiments showed that the initial threshold of friction wind velocity for the salt dust release was higher in clay flats(0.7–0.8 m/s)than in salt crusts(0.5–0.6 m/s).Moreover,the particle leap impact processes occurring under natural conditions may reduce this threshold value.Salinity was the main factor controlling the difference in the initial threshold of friction wind velocity for the salt dust release of clay flats and salt crusts.This study provides a scientific reference for understanding how salt dust is released from a lakebed,which may be used for ecological restoration of dry salt lakes.
基金Supported by High-efficiency Eco-agricultural Innovation Project of Taishan Industrial Leading Talent Project (LJNY202001)Liaocheng Scientific Research Project (GPY-2021-05-001)。
文摘[Objectives]The quality of pear wine is directly affected by parameter control in the production process, especially in the fermentation stage. The fermentation parameters of pear wine were controlled by studying the effects of fermentation parameters on the product, in order to optimize the fermentation parameters. [Methods]The fermentation conditions of pear wine were optimized by single factor experiments and an orthogonal experiment. [Results] The optimum fermentation conditions of pear wine were nitrogen source 1.0 g/L, fermentation temperature 20 ℃, and pH of fermentation liquid 4.3. The pear wine brewed was full, mellow and harmonious, and had a unique style. The ethanol content of the pear wine was 12.33 through physical and chemical analysis. [Conclusions] This study provides theoretical basis and technical support for the industrial production and promotion of pear wine.
文摘For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is compulsory.Thus,process analytical technology(PAT)that allows deeper insight into the process and results in a mathematical description of the process behavior as a simple function based on the most important process factors can help to achieve higher production efficiency and quality.The present study aims at characterizing a well-known industrial process,the transesterification reaction of rapeseed oil with methanol to produce fatty acid methyl esters(FAME)for usage as biodiesel in a continuous micro reactor set-up.To this end,a design of experiment approach is applied,where the effects of two process factors,the molar ratio and the total flow rate of the reactants,are investigated.The optimized process target response is the FAME mass fraction in the purified nonpolar phase of the product as a measure of reaction yield.The quantification is performed using attenuated total reflection infrared spectroscopy in combination with partial least squares regression.The data retrieved during the conduction of the DoE experimental plan were used for statistical analysis.A non-linear model indicating a synergistic interaction between the studied factors describes the reactor behavior with a high coefficient of determination(R^(2))of 0.9608.Thus,we applied a PAT approach to generate further insight into this established industrial process.
基金2022 Anhui Provincial Health Research Project (No.AHWJ2022b041)2021 Anhui Provincial Key Medical and Health Specialty Construction Project (No.Anhui Health Letter 2021-273)。
文摘Objective:Based on network pharmacology and molecular docking technology to explore the mechanism of Professor Cao Enze's application of Panax notoginseng in the treatment of membranous nephropathy.Methods:TCMSP database was used to obtain the effective components and corresponding target information of Panax notoginseng,and Gene Cards database was used to obtain the disease target genes of membranous nephropathy.The intersection targets of the two were taken and the Venn diagram was drawn.The STRING database was used to obtain the protein interaction relationship,and the PPI network diagram was constructed by Cytoscape 3.9.1 software to screen out the core targets of Panax notoginseng in the treatment of membranous nephropathy.GO function and KEGG pathway enrichment analysis were performed using the David database to obtain the potential pathway of Panax notoginseng in the treatment of membranous nephropathy.Finally,Autodock software was used to verify the molecular docking of the main active components of the drug with the core targets.Results:A total of 7 effective components such as quercetin,ginsenoside rh2,Mandenol and Stigmasterol were retrieved,and 127 potential targets of Panax notoginseng in the treatment of membranous nephropathy were screened out.By PPI network topology analysis,23 core targets such as JUN,TP53,RELA,AKT1 and MAPK1 were screened out.GO functional enrichment analysis contained 703 biological processes,55 cell components and 121 molecular functions,and KEGG signal pathway enrichment analysis enriched 171 signal pathways.The results of molecular docking showed that there was a strong binding ability between the main core targets and the main components of Panax notoginseng.Conclusion:Through network pharmacology,it is concluded that Panax notoginseng treats membranous nephropathy through multiple targets and multiple pathways,which provides a theoretical basis for subsequent basic research.
文摘This article investigates the dynamic relationship between technology and AI(artificial intelligence)and the role that societal requirements play in pushing AI research and adoption.Technology has advanced dramatically throughout the years,providing the groundwork for the rise of AI.AI systems have achieved incredible feats in various disciplines thanks to advancements in computer power,data availability,and complex algorithms.On the other hand,society’s needs for efficiency,enhanced healthcare,environmental sustainability,and personalized experiences have worked as powerful accelerators for AI’s progress.This article digs into how technology empowers AI and how societal needs dictate its progress,emphasizing their symbiotic relationship.The findings underline the significance of responsible AI research,which considers both technological prowess and ethical issues,to ensure that AI continues to serve the greater good.
基金This paper was supported by the 2021 School-Level Education Reform Project of Hainan Tropical Ocean University Fund(RHYjg2021sz03).
文摘As critical measures to educate and cultivate people’s morality,“Ideology and Politics of Course”has gradually become the focus in actual undergraduate education research in universities.Targeting the single ideological and political education mode and students’lack of interest in experimental courses,this paper,through various links,including pre-class preview,in-class teaching,and after-class data analysis,takes the common emitter single tube amplifier experiment as an example to organically integrate the excavated ideological and political elements with practical operation and carry out teaching case design and practice;realize the improvement of students’learning initiative and problem-analysis ability;and achieve the purpose of cultivating people throughout the whole process and in a comprehensive direction.