This paper investigates the distributed continuoustime aggregative optimization problem for second-order multiagent systems,where the local cost function is not only related to its own decision variables,but also to t...This paper investigates the distributed continuoustime aggregative optimization problem for second-order multiagent systems,where the local cost function is not only related to its own decision variables,but also to the aggregation of the decision variables of all the agents.By using the gradient descent method,the distributed average tracking(DAT)technique and the time-base generator(TBG)technique,a distributed continuous-time aggregative optimization algorithm is proposed.Subsequently,the optimality of the system's equilibrium point is analyzed,and the convergence of the closed-loop system is proved using the Lyapunov stability theory.Finally,the effectiveness of the proposed algorithm is validated through case studies on multirobot systems and power generation systems.展开更多
Dear Editor,This letter studies the distributed Nash equilibrium seeking problem of aggregative game,in which the decision of each player obeys second-order dynamics and is constrained by nonidentical convex sets.To s...Dear Editor,This letter studies the distributed Nash equilibrium seeking problem of aggregative game,in which the decision of each player obeys second-order dynamics and is constrained by nonidentical convex sets.To seek the generalized Nash equilibrium(GNE),a projectionbased distributed algorithm via constant step-sizes is developed with linear convergence.In particular,a variable tracking technique is incorporated to estimate the aggregative function,and an event-triggered mechanism is designed to reduce the communication cost.Finally,a numerical example demonstrates the theoretical results.展开更多
In this paper,we investigate the distributed Nash equilibrium(NE)seeking problem for aggregative games with multiple uncertain Euler–Lagrange(EL)systems over jointly connected and weight-balanced switching networks.T...In this paper,we investigate the distributed Nash equilibrium(NE)seeking problem for aggregative games with multiple uncertain Euler–Lagrange(EL)systems over jointly connected and weight-balanced switching networks.The designed distributed controller consists of two parts:a dynamic average consensus part that asymptotically reproduces the unknown NE,and an adaptive reference-tracking module responsible for steering EL systems’positions to track a desired trajectory.The generalized Barbalat’s Lemma is used to overcome the discontinuity of the closed-loop system caused by the switching networks.The proposed algorithm is illustrated by a sensor network deployment problem.展开更多
Game theory-based models and design tools have gained substantial prominence for controlling and optimizing behavior within distributed engineering systems due to the inherent distribution of decisions among individua...Game theory-based models and design tools have gained substantial prominence for controlling and optimizing behavior within distributed engineering systems due to the inherent distribution of decisions among individuals.In non-cooperative settings,aggregative games serve as a mathematical framework model for the interdependent optimal decision-making problem among a group of non-cooperative players.In such scenarios,each player's decision is influenced by an aggregation of all players'decisions.Nash equilibrium(NE)seeking in aggregative games has emerged as a vibrant topic driven by applications that harness the aggregation property.This paper presents a comprehensive overview of the current research on aggregative games with a focus on communication topology.A systematic classification is conducted on distributed algorithm research based on communication topologies such as undirected networks,directed networks,and time-varying networks.Furthermore,it sorts out the challenges and compares the algorithms'convergence performance.It also delves into real-world applications of distributed optimization techniques grounded in aggregative games.Finally,it proposes several challenges that can guide future research directions.展开更多
To broaden the frequency width and increase the damping coefficient of a dynamic pressure damper, we designed an aggregative dynamic pressure damper (ADPD). Combined with the advantages of traditional dynamic pressure...To broaden the frequency width and increase the damping coefficient of a dynamic pressure damper, we designed an aggregative dynamic pressure damper (ADPD). Combined with the advantages of traditional dynamic pressure dampers (TDPD), ADPD can not only increase the damping coefficient in wide frequency range for valve control system, but also absorb partial pressure pulsations and impacts in the low and high frequency fields. Based on the theoretical research and the analysis compared with TDPD, we concluded that the ADPD was superior to the TDPD in the middle high frequency field, and the main parameters influencing the performance of the damper were the damping stiffness, orifice flow coefficient, pre-charge pressure, and the volume of the damper accumulator.展开更多
To analyze China’s fluctuating situation of the factor input and aggregative productivity is not only the main method to seek the source of the economic growth but also the main way to weigh the level of economic gro...To analyze China’s fluctuating situation of the factor input and aggregative productivity is not only the main method to seek the source of the economic growth but also the main way to weigh the level of economic growth quality.As to economic growth ofa country,the improvementofthe productivity is extremely important.The growth of the output can be realized through two kinds of ways: increasing the quantity of factor input of or improving the efficiency of the input and output.There fore, the level of economic growth quality does not mainly depend on the amount of invested factor,but the importance of improving the productivity since resources are rare. The relative improvement of efficiency in use of the invested factor marks the economic growing quality.So,in order to understand the economic growth quality of China to some extent, it must analyze Chinese factor input and aggregative productivity. This is the main topic that this text will be probed into.展开更多
BACKGROUND At the end of 2019,a new epidemic of viral pneumonia emerged in China and was determined to be caused by a novel coronavirus,which was named coronavirus disease 2019(COVID-19)by the World Health Organizatio...BACKGROUND At the end of 2019,a new epidemic of viral pneumonia emerged in China and was determined to be caused by a novel coronavirus,which was named coronavirus disease 2019(COVID-19)by the World Health Organization.The epidemic quickly spread,causing a worldwide pandemic.Scientists and clinicians across the globe have shifted their research efforts towards understanding the virus itself and its epidemiology.CASE SUMMARY In mid-January 2020,a Chinese family made a visit to a local city,and within the next 2 wk one after another fell ill with COVID-19.At the beginning of their first illness onset,the family had eaten in a restaurant,which led to the subsequent illness onset in another two families.All cases were diagnosed as COVID-19 by real-time fluorescent reverse transcription-polymerase chain reaction.Epidemiological investigation showed that the transmission chain was complete.CONCLUSION This chain of social exposure highlights the danger of group aggregative behavior for spread of COVID-19.展开更多
Enteroaggregative Escherichia coli (EAggEC) strains cause the persistent diarrhea in infants and compromised hosts in developing countries. These strains are currently defined as E. coli that adheres to HEp-2 cells in...Enteroaggregative Escherichia coli (EAggEC) strains cause the persistent diarrhea in infants and compromised hosts in developing countries. These strains are currently defined as E. coli that adheres to HEp-2 cells in an aggregative adherence (AA) pattern. In this study, we compared 4 different rapid methods for the detection of EAggEC using a PCR assay, clump formation test, glass slide adherence assay, and the HEp-2 cell adherence assay. Out of 683 E. coli strains isolated from diarrheal stool samples, we detected 17 aggR and/or clump-positive strains, and identified 2 aggR-positive, clump-negative strains and 2 aggR-negative, clump-positive strains. All the aggR positive and clump positive strains also showed positive results in glass slide adherence and HEp-2 cell adherence assays. From all these results, we suggest the following procedure for the rapid identification of EAggEC strains: first, screen E. coli strains with the clump formation test and subsequently perform the glass slide adherence assay to observe AA for confirmation.展开更多
Generally,energy trading in smart grid is realized by microgrids.Correspondingly,energy trading in energy internet relies on small-scale energy systems,named as Weenergies(WEs).Previous works on the distributed energy...Generally,energy trading in smart grid is realized by microgrids.Correspondingly,energy trading in energy internet relies on small-scale energy systems,named as Weenergies(WEs).Previous works on the distributed energy trading focused on the trading platform or trading mechanism based on distributed communication.However,most ignored the fact that there is no express delivery of energy trading,and the transmission of energy depends on a fixed physical topology.Energy transactions without considering the transmission distance will increase the difficulty of energy scheduling and the transmission cost of energy.Aiming at this problem,an aggregation game among WEs is proposed for two-way multi-energy trading,and a distributed algorithm is designed to solve the Nash equilibrium.Since each WE only needs to communicate with its neighbors to exchange information,this distributed process reduces communication burden and improves information security.Furthermore,a multi-energy transmission optimization model is established to determine the transmission path of the transmission energy,which can minimize the transmission cost.Subsequently,to reduce the influence of real-time fluctuations of renewable energy and load,a receding horizon control algorithm is designed to improve the reliability of the proposed game.Finally,the effectiveness in dealing with two-way multi-energy trading of the proposed strategy is verified through simulations on the five connected WEs.展开更多
In this paper,the authors propose a distributed gradient tracking algorithm with compressed communication to address an aggregative optimization problem under communication constraints.The problem involves minimizing ...In this paper,the authors propose a distributed gradient tracking algorithm with compressed communication to address an aggregative optimization problem under communication constraints.The problem involves minimizing the sum of local cost functions,where each cost function depends on both local and global state variables.The authors aim to solve this optimization problem through local computation and efficient communication among agents in a network,without the need for a central coordinator.The proposed algorithm combines the variable tracking method to estimate global state variables and a compressed communication scheme to reduce communication costs during the optimization process.Among which,the compressed scheme can encompass both biased and unbiased compressors.Despite the loss of some transmitting information due to quantization,the proposed algorithm can still achieve the exact optimal solution with a linear convergence rate.The authors validate the theoretical results through simulation experiments on an optimal placement problem.展开更多
Distributed Nash equilibrium seeking of aggregative games is investigated and a continuous-time algorithm is proposed.The algorithm is designed by virtue of projected gradient play dynamics and aggregation tracking dy...Distributed Nash equilibrium seeking of aggregative games is investigated and a continuous-time algorithm is proposed.The algorithm is designed by virtue of projected gradient play dynamics and aggregation tracking dynamics,and is applicable to games with constrained strategy sets and weight-balanced communication graphs.The key feature of our method is that the proposed projected dynamics achieves exponential convergence,whereas such convergence results are only obtained for non-projected dynamics in existing works on distributed optimization and equilibrium seeking.Numerical examples illustrate the effectiveness of our methods.展开更多
Many architectural research studies have focused on creating new materials to reduce the exploitation of non-renewable natural resources,achieve sustainable development,and reduce carbon emissions.Desert sand(DS)has a...Many architectural research studies have focused on creating new materials to reduce the exploitation of non-renewable natural resources,achieve sustainable development,and reduce carbon emissions.Desert sand(DS)has attracted interest from researchers who have conducted numerous experimental investigations as a possible replacement for river sand.The idea of utilising DS in place of natural fine aggregates in construction has been demonstrated in the literature.However,to analyse and gain confidence in using DS in concrete,a thorough study of its various properties is needed.Therefore,this study addresses the morphological,chemical,and physical characteristics of DS from multiple perspectives.This review presents a study on the durability of desert sand concrete(DSC)and the use of DS cement-based products,and highlights investigations on the design of mix proportions and fresh and hardened properties of DSC.Research issues are emerging around the use of DS in engineered cementitious composites(ECC)materials and the investigation of desert sand powder(DSP)as mineral admixtures.Many issues need to be resolved quickly,which is crucial for the use of DS.In summary,research on DS is still in its early stages,and no systematic research results have been obtained at present.This review makes several recommendations and attempts to explain why DS will likely be widely used as a building material in the future.展开更多
Raman imaging,as a molecular spectroscopy technique,has been widely studied and applied in research fields such as life sciences and food safety due to its excellent specificity and high resolution.However,its develop...Raman imaging,as a molecular spectroscopy technique,has been widely studied and applied in research fields such as life sciences and food safety due to its excellent specificity and high resolution.However,its development still faces challenges such as weak signals,slow acquisition speed,and insufficient penetration depth.In recent years,the rapid development of aggregate science has provided new insights for addressing these limitations.Aggregation-induced emission(AIE)materials exhibit enhanced signals in the aggregated state,which may compensate for the inherent weak Raman signals.This article reviews the cutting-edge progress of Raman imaging technology and its current status in cross-disciplinary research with aggregate science,emphasizing the strategy of constructing AIE-Raman dual-responsive probes through molecular engineering to achieve functional complementarity between fluorescence localization and Raman quantification,thereby significantly improving detection sensitivity and specificity.These probes have demonstrated single-cell resolution and high spatiotemporal accuracy in applications such as tumor surgical navigation,diagnosis and treatment of drug-resistant bacteria,and dynamic monitoring of organelles.We also analyze the bottlenecks in this field,such as biological safety and the complexity of molecular design,and outline the future development directions,including intelligent responsive probes,artificial intelligence-assisted analysis,and multimodal fusion platforms.The integration of Raman imaging and AIE sheds new light in the field of medical imaging.展开更多
In modern construction,Lightweight Aggregate Concrete(LWAC)has been recognized as a vital material of concern because of its unique properties,such as reduced density and improved thermal insulation.Despite the extens...In modern construction,Lightweight Aggregate Concrete(LWAC)has been recognized as a vital material of concern because of its unique properties,such as reduced density and improved thermal insulation.Despite the extensive knowledge regarding its macroscopic properties,there is a wide knowledge gap in understanding the influence of microscale parameters like aggregate porosity and volume ratio on the mechanical response of LWAC.This study aims to bridge this knowledge gap,spurred by the need to enhance the predictability and applicability of LWAC in various construction environments.With the help of advanced numerical methods,including the finite element method and a random circular aggregate model,this study critically evaluates the role played by these microscale factors.We found that an increase in the aggregate porosity from 23.5%to 48.5%leads to a drastic change of weakness from the bonding interface to the aggregate,reducing compressive strength by up to 24.2%and tensile strength by 27.8%.Similarly,the increase in the volume ratio of lightweight aggregate from 25%to 40%leads to a reduction in compressive strength by 13.0%and tensile strength by 9.23%.These results highlight the imperative role of microscale properties on the mechanical properties of LWAC.By supplying precise quantitative details on the effect of porosity and aggregate volume ratio,this research makes significant contributions to construction materials science by providing useful recommendations for the creation and optimization of LWAC with improved performance and sustainability in construction.展开更多
Neurodegenerative diseases are chronic,age-related disorders characterized by a relentless,irreversible,and selective loss of neurons in motor,sensory,or cognitive systems(Gao et al.,2019).Despite their heterogeneity,...Neurodegenerative diseases are chronic,age-related disorders characterized by a relentless,irreversible,and selective loss of neurons in motor,sensory,or cognitive systems(Gao et al.,2019).Despite their heterogeneity,a common pathological feature across many of these diseases is the accumulation of aggregate-prone proteins.Particularly,the cytoplasmic aggregation in neurons of the Transactive response DNA-binding protein 43(TDP-43).展开更多
In this paper,we consider the Nash equilibrium(NE)seeking problem for aggregative games and design a distributed heavy-ball algorithm to solve it.This algorithm has faster convergence rate than the well-known distribu...In this paper,we consider the Nash equilibrium(NE)seeking problem for aggregative games and design a distributed heavy-ball algorithm to solve it.This algorithm has faster convergence rate than the well-known distributed first-order algorithms for aggregative games.In order to seek the NE,each player needs to exchange information with its neighbours as well as a cen-tral aggregation.For aggregative games,the aggregative term can be either linear or nonlinear in this paper.Furthermore,we consider the generalised Nash equilibrium seeking problem for aggregative games by taking into account the linear coupled constraints among players,and modify our initial algorithm to include game constraints.展开更多
To explore mix proportion design of RAC with aggregates tightly packed,the dry and wet packing density of recycled coarse aggregates mixture system and recycled coarse and fine aggregates were tested,then the influenc...To explore mix proportion design of RAC with aggregates tightly packed,the dry and wet packing density of recycled coarse aggregates mixture system and recycled coarse and fine aggregates were tested,then the influence of replacement rate and particle size ratio on the packing density of particle system was explored,the packing density prediction model of recycled coarse aggregates based on particle morphology was constructed,and the mix proportion optimization for recycled aggregate concrete with dry-wet packing model was carried out.The experimental results show that,with the increasing of recycled aggregate replacement rate or fine-grained volume ratio,the dry packing density of recycled coarse aggregates decreases gradually.With the increasing of replacement rate,the particle gradation can be optimized by increasing coarsegrained volume ratio.There is a significant effect for particle morphology parameter K and the particle size ratio on the packing density of the binary mixed system,and the packing density prediction model of recycled coarse aggregates based on particle morphology was constructed.The maximum increase in compressive strength and tensile strength of RAC with mix proportion optimized by the dry-wet packing model are 12.94%and 11.09%,and the cementitious materials is reduced by 21.83%,then the superiority of the mix proportion optimization of RAC with the dry-wet close packing model is confirmed.The results of this paper can provide a theoretical basis for the mix proportion design of RAC.展开更多
To promote the application of green recycled construction materials in civil engineering,this study presents a statistical damage constitutive model for polypropylene fiber recycled fine aggregate concrete(PRFAC),base...To promote the application of green recycled construction materials in civil engineering,this study presents a statistical damage constitutive model for polypropylene fiber recycled fine aggregate concrete(PRFAC),based on the strain equivalence principle and the assumption that microelement strength follows a Weibull statistical distribution.The proposed model incorporates the Drucker-Prager failure criterion.By examining the influence of Weibull distribution parameters m and S_(0)on the stress-strain response,empirical relationships were established between the fine aggregate replacement ratio and the distribution parameters.This enabled the derivation of a theoretical stress-strain curve accounting for variable recycled fine aggragate(RFA)replacement ratios.The experimental results show that the proposed model exhibits high agreement with measured data and effectively captures the increased brittleness of PRFAC with higher RFA replacement ratios.Moreover,increasing the replacement rate accelerates internal crack propagation,reduces deformability and toughness,and significantly hastens the accumulation of internal damage in PRFAC.展开更多
Freeze-thaw cycles(FTCs)have an important effect on soil aggregate stability by altering soil structures,thereby influencing soil wind and water erosion on the eastern Qinghai-Tibet Plateau.However,the effects of FTCs...Freeze-thaw cycles(FTCs)have an important effect on soil aggregate stability by altering soil structures,thereby influencing soil wind and water erosion on the eastern Qinghai-Tibet Plateau.However,the effects of FTCs on the stability of these soils remain unclear.Here,we conducted freeze-thaw simulations in laboratory to investigate the effects of FTCs(0 to 15 cycles)on the wet-and dry-sieving aggregate stability of undisturbed sandy loam from Maqu county,which was treated with different initial soil moisture contents(1%to 25%in increments of 4%)and initial aggregate diameters(<2,2-5,5-10,and 10-15 mm).Results show that soil aggregates with initial diameters larger than 2 mm exhibit higher soil organic carbon contents(1.45%-1.57%)and silt contents(34.63%-35.52%)than those smaller than 2 mm(0.93%and 31.38%,respectively).The stability of both wet-and dry-sieving aggregates increases with larger initial diameters.Increasing initial soil moisture content from 1%to 25%reduces aggregate stability,with reductions of 2.4%-88.0%for wet-sieving aggregates and 2.1%-25.5%for dry-sieving aggregates(>2 mm).With increasing FTCs,wet-sieving aggregate(>2 mm)stability exhibits a fluctuating upward trend,with increases of 79.2%-87.4%after 15 FTCs,while dry-sieving aggregate(>2 mm)stability decreases significantly(5.7%-21.7%)upon the first FTC and remains unchanged thereafter.The stability of both the wet-and dry-sieving aggregates smaller than 2 mm remains unchanged with increasing FTCs(p>0.05).SOC content decreases by 22.3%on average with increasing FTCs from 1 to 15 and shows no significant correlations with wet-and dry-sieving aggregate stability.Higher silt content(r=0.39,p<0.05)and lower sand content(r=-0.38,p<0.05)enhances the wet-sieving aggregate stability of sandy loam.Frequent FTCs tend to improve wet-sieving aggregate stability but reduce dry-sieving aggregate stability in the sandy loam.The findings provide certain guidance for preventing freeze-thaw-induced wind erosion.展开更多
Protein aggregates,mitochondrial import stress and neurodegenerative disorders:A salient hallmark of several neurodegenerative diseases,including Parkinson’s disease,is the abundance of protein aggregates(Goiran et a...Protein aggregates,mitochondrial import stress and neurodegenerative disorders:A salient hallmark of several neurodegenerative diseases,including Parkinson’s disease,is the abundance of protein aggregates(Goiran et al.,2022).This molecular event is believed to lead to activation of stress pathways ultimately resulting in cellular dysfunction(Eldeeb et al.,2022).Accordingly,many lines of research investigations focused on dampening the formation of protein aggregates or augmenting the clearance of protein aggregates as a potential therapeutic strategy to counteract the progression of neurodegenerative diseases,albeit with little success(Costa-Mattioli and Walter,2020).Cell stress cues such as the accumulation of protein aggregates lead to the activation of stress response pathways that aid cells in responding to the damage.Despite the notion that the transient activation of these pathways helps cells cope with stressors,persistent activation can induce unwanted apoptosis of cells and reduce overall tissue strength as well as lead to an accumulation of aggregation-prone proteins(Hetz and Papa,2018).Mutations in proteins involved in stress signaling termination can cause conditions like ataxia and early-onset dementia(Conroy et al.,2014).Therefore,it is crucial for stress response signaling to be turned off once conditions have improved.Nevertheless,the mechanisms by which cells silence these signals are still elusive.展开更多
基金supported by the National Key Research and Development Program of China(2025YFE0213100)the National Natural Science Foundation of China(62422315,62573348)+1 种基金the Natural Science Basic Research Program of Shaanxi(2025JC-YBMS-667)the“Shuang Yi Liu”Construction Foundation(25GH02010366)。
文摘This paper investigates the distributed continuoustime aggregative optimization problem for second-order multiagent systems,where the local cost function is not only related to its own decision variables,but also to the aggregation of the decision variables of all the agents.By using the gradient descent method,the distributed average tracking(DAT)technique and the time-base generator(TBG)technique,a distributed continuous-time aggregative optimization algorithm is proposed.Subsequently,the optimality of the system's equilibrium point is analyzed,and the convergence of the closed-loop system is proved using the Lyapunov stability theory.Finally,the effectiveness of the proposed algorithm is validated through case studies on multirobot systems and power generation systems.
基金supported by the National Natural Science Foundation of China(62473048,61925303,62088101,62273195,U19B2029).
文摘Dear Editor,This letter studies the distributed Nash equilibrium seeking problem of aggregative game,in which the decision of each player obeys second-order dynamics and is constrained by nonidentical convex sets.To seek the generalized Nash equilibrium(GNE),a projectionbased distributed algorithm via constant step-sizes is developed with linear convergence.In particular,a variable tracking technique is incorporated to estimate the aggregative function,and an event-triggered mechanism is designed to reduce the communication cost.Finally,a numerical example demonstrates the theoretical results.
基金supported by the Research Grants Council of the Hong Kong Special Administration Region under the Grant No.14201621。
文摘In this paper,we investigate the distributed Nash equilibrium(NE)seeking problem for aggregative games with multiple uncertain Euler–Lagrange(EL)systems over jointly connected and weight-balanced switching networks.The designed distributed controller consists of two parts:a dynamic average consensus part that asymptotically reproduces the unknown NE,and an adaptive reference-tracking module responsible for steering EL systems’positions to track a desired trajectory.The generalized Barbalat’s Lemma is used to overcome the discontinuity of the closed-loop system caused by the switching networks.The proposed algorithm is illustrated by a sensor network deployment problem.
基金supported in part by the Fundamental Research Funds for the Central Universities(SWU-XDJH202312)the National Natural Science Foundation of China(62173278)the Chongqing Science Fund for Distinguished Young Scholars(2024NSCQJQX0103).
文摘Game theory-based models and design tools have gained substantial prominence for controlling and optimizing behavior within distributed engineering systems due to the inherent distribution of decisions among individuals.In non-cooperative settings,aggregative games serve as a mathematical framework model for the interdependent optimal decision-making problem among a group of non-cooperative players.In such scenarios,each player's decision is influenced by an aggregation of all players'decisions.Nash equilibrium(NE)seeking in aggregative games has emerged as a vibrant topic driven by applications that harness the aggregation property.This paper presents a comprehensive overview of the current research on aggregative games with a focus on communication topology.A systematic classification is conducted on distributed algorithm research based on communication topologies such as undirected networks,directed networks,and time-varying networks.Furthermore,it sorts out the challenges and compares the algorithms'convergence performance.It also delves into real-world applications of distributed optimization techniques grounded in aggregative games.Finally,it proposes several challenges that can guide future research directions.
文摘To broaden the frequency width and increase the damping coefficient of a dynamic pressure damper, we designed an aggregative dynamic pressure damper (ADPD). Combined with the advantages of traditional dynamic pressure dampers (TDPD), ADPD can not only increase the damping coefficient in wide frequency range for valve control system, but also absorb partial pressure pulsations and impacts in the low and high frequency fields. Based on the theoretical research and the analysis compared with TDPD, we concluded that the ADPD was superior to the TDPD in the middle high frequency field, and the main parameters influencing the performance of the damper were the damping stiffness, orifice flow coefficient, pre-charge pressure, and the volume of the damper accumulator.
文摘To analyze China’s fluctuating situation of the factor input and aggregative productivity is not only the main method to seek the source of the economic growth but also the main way to weigh the level of economic growth quality.As to economic growth ofa country,the improvementofthe productivity is extremely important.The growth of the output can be realized through two kinds of ways: increasing the quantity of factor input of or improving the efficiency of the input and output.There fore, the level of economic growth quality does not mainly depend on the amount of invested factor,but the importance of improving the productivity since resources are rare. The relative improvement of efficiency in use of the invested factor marks the economic growing quality.So,in order to understand the economic growth quality of China to some extent, it must analyze Chinese factor input and aggregative productivity. This is the main topic that this text will be probed into.
基金The Guangzhou Science and Technology Program Key Projects,No.201704030132.
文摘BACKGROUND At the end of 2019,a new epidemic of viral pneumonia emerged in China and was determined to be caused by a novel coronavirus,which was named coronavirus disease 2019(COVID-19)by the World Health Organization.The epidemic quickly spread,causing a worldwide pandemic.Scientists and clinicians across the globe have shifted their research efforts towards understanding the virus itself and its epidemiology.CASE SUMMARY In mid-January 2020,a Chinese family made a visit to a local city,and within the next 2 wk one after another fell ill with COVID-19.At the beginning of their first illness onset,the family had eaten in a restaurant,which led to the subsequent illness onset in another two families.All cases were diagnosed as COVID-19 by real-time fluorescent reverse transcription-polymerase chain reaction.Epidemiological investigation showed that the transmission chain was complete.CONCLUSION This chain of social exposure highlights the danger of group aggregative behavior for spread of COVID-19.
文摘Enteroaggregative Escherichia coli (EAggEC) strains cause the persistent diarrhea in infants and compromised hosts in developing countries. These strains are currently defined as E. coli that adheres to HEp-2 cells in an aggregative adherence (AA) pattern. In this study, we compared 4 different rapid methods for the detection of EAggEC using a PCR assay, clump formation test, glass slide adherence assay, and the HEp-2 cell adherence assay. Out of 683 E. coli strains isolated from diarrheal stool samples, we detected 17 aggR and/or clump-positive strains, and identified 2 aggR-positive, clump-negative strains and 2 aggR-negative, clump-positive strains. All the aggR positive and clump positive strains also showed positive results in glass slide adherence and HEp-2 cell adherence assays. From all these results, we suggest the following procedure for the rapid identification of EAggEC strains: first, screen E. coli strains with the clump formation test and subsequently perform the glass slide adherence assay to observe AA for confirmation.
基金supported by the National Key Research and Development Program of China(2018YFA0702200)National Natural Science Foundation of China(No.62073065).
文摘Generally,energy trading in smart grid is realized by microgrids.Correspondingly,energy trading in energy internet relies on small-scale energy systems,named as Weenergies(WEs).Previous works on the distributed energy trading focused on the trading platform or trading mechanism based on distributed communication.However,most ignored the fact that there is no express delivery of energy trading,and the transmission of energy depends on a fixed physical topology.Energy transactions without considering the transmission distance will increase the difficulty of energy scheduling and the transmission cost of energy.Aiming at this problem,an aggregation game among WEs is proposed for two-way multi-energy trading,and a distributed algorithm is designed to solve the Nash equilibrium.Since each WE only needs to communicate with its neighbors to exchange information,this distributed process reduces communication burden and improves information security.Furthermore,a multi-energy transmission optimization model is established to determine the transmission path of the transmission energy,which can minimize the transmission cost.Subsequently,to reduce the influence of real-time fluctuations of renewable energy and load,a receding horizon control algorithm is designed to improve the reliability of the proposed game.Finally,the effectiveness in dealing with two-way multi-energy trading of the proposed strategy is verified through simulations on the five connected WEs.
基金supported by the National Key Research and Development Program of China under Grant No.2022YFA1004701the National Natural Science Foundation of China under Grant No.72271187+1 种基金the Fundamental Research Funds for the Central Universitiespartially by Shanghai Municipal Science and Technology Major Project under Grant No.2021SHZDZX0100。
文摘In this paper,the authors propose a distributed gradient tracking algorithm with compressed communication to address an aggregative optimization problem under communication constraints.The problem involves minimizing the sum of local cost functions,where each cost function depends on both local and global state variables.The authors aim to solve this optimization problem through local computation and efficient communication among agents in a network,without the need for a central coordinator.The proposed algorithm combines the variable tracking method to estimate global state variables and a compressed communication scheme to reduce communication costs during the optimization process.Among which,the compressed scheme can encompass both biased and unbiased compressors.Despite the loss of some transmitting information due to quantization,the proposed algorithm can still achieve the exact optimal solution with a linear convergence rate.The authors validate the theoretical results through simulation experiments on an optimal placement problem.
基金This work was partially supported by the National Natural Science Foundation of China under Grant 61903027,72171171,62003239Shanghai Municipal Science and Technology Major Project under Grant 2021SHZDZX0100Shanghai Sailing Program under Grant 20YF1453000.
文摘Distributed Nash equilibrium seeking of aggregative games is investigated and a continuous-time algorithm is proposed.The algorithm is designed by virtue of projected gradient play dynamics and aggregation tracking dynamics,and is applicable to games with constrained strategy sets and weight-balanced communication graphs.The key feature of our method is that the proposed projected dynamics achieves exponential convergence,whereas such convergence results are only obtained for non-projected dynamics in existing works on distributed optimization and equilibrium seeking.Numerical examples illustrate the effectiveness of our methods.
文摘Many architectural research studies have focused on creating new materials to reduce the exploitation of non-renewable natural resources,achieve sustainable development,and reduce carbon emissions.Desert sand(DS)has attracted interest from researchers who have conducted numerous experimental investigations as a possible replacement for river sand.The idea of utilising DS in place of natural fine aggregates in construction has been demonstrated in the literature.However,to analyse and gain confidence in using DS in concrete,a thorough study of its various properties is needed.Therefore,this study addresses the morphological,chemical,and physical characteristics of DS from multiple perspectives.This review presents a study on the durability of desert sand concrete(DSC)and the use of DS cement-based products,and highlights investigations on the design of mix proportions and fresh and hardened properties of DSC.Research issues are emerging around the use of DS in engineered cementitious composites(ECC)materials and the investigation of desert sand powder(DSP)as mineral admixtures.Many issues need to be resolved quickly,which is crucial for the use of DS.In summary,research on DS is still in its early stages,and no systematic research results have been obtained at present.This review makes several recommendations and attempts to explain why DS will likely be widely used as a building material in the future.
文摘Raman imaging,as a molecular spectroscopy technique,has been widely studied and applied in research fields such as life sciences and food safety due to its excellent specificity and high resolution.However,its development still faces challenges such as weak signals,slow acquisition speed,and insufficient penetration depth.In recent years,the rapid development of aggregate science has provided new insights for addressing these limitations.Aggregation-induced emission(AIE)materials exhibit enhanced signals in the aggregated state,which may compensate for the inherent weak Raman signals.This article reviews the cutting-edge progress of Raman imaging technology and its current status in cross-disciplinary research with aggregate science,emphasizing the strategy of constructing AIE-Raman dual-responsive probes through molecular engineering to achieve functional complementarity between fluorescence localization and Raman quantification,thereby significantly improving detection sensitivity and specificity.These probes have demonstrated single-cell resolution and high spatiotemporal accuracy in applications such as tumor surgical navigation,diagnosis and treatment of drug-resistant bacteria,and dynamic monitoring of organelles.We also analyze the bottlenecks in this field,such as biological safety and the complexity of molecular design,and outline the future development directions,including intelligent responsive probes,artificial intelligence-assisted analysis,and multimodal fusion platforms.The integration of Raman imaging and AIE sheds new light in the field of medical imaging.
基金supported by National Science Foundation of China(10972015,11172015)the Beijing Natural Science Foundation(8162008).
文摘In modern construction,Lightweight Aggregate Concrete(LWAC)has been recognized as a vital material of concern because of its unique properties,such as reduced density and improved thermal insulation.Despite the extensive knowledge regarding its macroscopic properties,there is a wide knowledge gap in understanding the influence of microscale parameters like aggregate porosity and volume ratio on the mechanical response of LWAC.This study aims to bridge this knowledge gap,spurred by the need to enhance the predictability and applicability of LWAC in various construction environments.With the help of advanced numerical methods,including the finite element method and a random circular aggregate model,this study critically evaluates the role played by these microscale factors.We found that an increase in the aggregate porosity from 23.5%to 48.5%leads to a drastic change of weakness from the bonding interface to the aggregate,reducing compressive strength by up to 24.2%and tensile strength by 27.8%.Similarly,the increase in the volume ratio of lightweight aggregate from 25%to 40%leads to a reduction in compressive strength by 13.0%and tensile strength by 9.23%.These results highlight the imperative role of microscale properties on the mechanical properties of LWAC.By supplying precise quantitative details on the effect of porosity and aggregate volume ratio,this research makes significant contributions to construction materials science by providing useful recommendations for the creation and optimization of LWAC with improved performance and sustainability in construction.
基金funded by the“Instituto de Salud Carlos III”(PI 17-000134,PI 20-0155,PI23/00176)the“Diputaciode Lleida”(PP10601-PIRS2021)to MPO+2 种基金Also from the“Diputaciode Lleida”(PP10605-PIRS2021)the“Generalitat de Catalunya”:Agency for Management of University and Research Grants(2021SGR00990)to RPSupport was also received in the form of a FUNDELA Grant,“RedELA-Plataforma Investigacion”and the“Fundacio Miquel Valls”(Jack Van den Hoek donation)(to MPO)。
文摘Neurodegenerative diseases are chronic,age-related disorders characterized by a relentless,irreversible,and selective loss of neurons in motor,sensory,or cognitive systems(Gao et al.,2019).Despite their heterogeneity,a common pathological feature across many of these diseases is the accumulation of aggregate-prone proteins.Particularly,the cytoplasmic aggregation in neurons of the Transactive response DNA-binding protein 43(TDP-43).
基金supported by NSFC[grant numbers 61663026,61963028,62066026,61866023]Jiangxi NSF[grant number 20192BAB207025].
文摘In this paper,we consider the Nash equilibrium(NE)seeking problem for aggregative games and design a distributed heavy-ball algorithm to solve it.This algorithm has faster convergence rate than the well-known distributed first-order algorithms for aggregative games.In order to seek the NE,each player needs to exchange information with its neighbours as well as a cen-tral aggregation.For aggregative games,the aggregative term can be either linear or nonlinear in this paper.Furthermore,we consider the generalised Nash equilibrium seeking problem for aggregative games by taking into account the linear coupled constraints among players,and modify our initial algorithm to include game constraints.
基金Funded by joint Funds of the National Natural Science Foundation of China(No.U1904188)the Key Research Project of Henan Province for Colleges and Universities(No.26A560009)+3 种基金the Jiaozuo City Science and Technology Planning Project(No.2025210099)the Henan Provincial Science and Technology Research Project(No.252102320305)the Natural Science Foundation of Henan Province(No.252300421917)the Project by Key Laboratory of Intelligent Construction and Safety Operation and Maintenance of Underground Engineering in Henan Province(No.KFKT2024-01)。
文摘To explore mix proportion design of RAC with aggregates tightly packed,the dry and wet packing density of recycled coarse aggregates mixture system and recycled coarse and fine aggregates were tested,then the influence of replacement rate and particle size ratio on the packing density of particle system was explored,the packing density prediction model of recycled coarse aggregates based on particle morphology was constructed,and the mix proportion optimization for recycled aggregate concrete with dry-wet packing model was carried out.The experimental results show that,with the increasing of recycled aggregate replacement rate or fine-grained volume ratio,the dry packing density of recycled coarse aggregates decreases gradually.With the increasing of replacement rate,the particle gradation can be optimized by increasing coarsegrained volume ratio.There is a significant effect for particle morphology parameter K and the particle size ratio on the packing density of the binary mixed system,and the packing density prediction model of recycled coarse aggregates based on particle morphology was constructed.The maximum increase in compressive strength and tensile strength of RAC with mix proportion optimized by the dry-wet packing model are 12.94%and 11.09%,and the cementitious materials is reduced by 21.83%,then the superiority of the mix proportion optimization of RAC with the dry-wet close packing model is confirmed.The results of this paper can provide a theoretical basis for the mix proportion design of RAC.
基金The National Natural Science Foundation of China(No.52168022).
文摘To promote the application of green recycled construction materials in civil engineering,this study presents a statistical damage constitutive model for polypropylene fiber recycled fine aggregate concrete(PRFAC),based on the strain equivalence principle and the assumption that microelement strength follows a Weibull statistical distribution.The proposed model incorporates the Drucker-Prager failure criterion.By examining the influence of Weibull distribution parameters m and S_(0)on the stress-strain response,empirical relationships were established between the fine aggregate replacement ratio and the distribution parameters.This enabled the derivation of a theoretical stress-strain curve accounting for variable recycled fine aggragate(RFA)replacement ratios.The experimental results show that the proposed model exhibits high agreement with measured data and effectively captures the increased brittleness of PRFAC with higher RFA replacement ratios.Moreover,increasing the replacement rate accelerates internal crack propagation,reduces deformability and toughness,and significantly hastens the accumulation of internal damage in PRFAC.
基金supported by National Natural Science Foundation of China(Grant No.42201080)Young Scientific and Technological Talents Program of Shaanxi Province(Grant No.2025ZC-KJXX-57)Special Scientific Research Program of the Shaanxi Provincial Department of Education(Grant No.21JK0967)。
文摘Freeze-thaw cycles(FTCs)have an important effect on soil aggregate stability by altering soil structures,thereby influencing soil wind and water erosion on the eastern Qinghai-Tibet Plateau.However,the effects of FTCs on the stability of these soils remain unclear.Here,we conducted freeze-thaw simulations in laboratory to investigate the effects of FTCs(0 to 15 cycles)on the wet-and dry-sieving aggregate stability of undisturbed sandy loam from Maqu county,which was treated with different initial soil moisture contents(1%to 25%in increments of 4%)and initial aggregate diameters(<2,2-5,5-10,and 10-15 mm).Results show that soil aggregates with initial diameters larger than 2 mm exhibit higher soil organic carbon contents(1.45%-1.57%)and silt contents(34.63%-35.52%)than those smaller than 2 mm(0.93%and 31.38%,respectively).The stability of both wet-and dry-sieving aggregates increases with larger initial diameters.Increasing initial soil moisture content from 1%to 25%reduces aggregate stability,with reductions of 2.4%-88.0%for wet-sieving aggregates and 2.1%-25.5%for dry-sieving aggregates(>2 mm).With increasing FTCs,wet-sieving aggregate(>2 mm)stability exhibits a fluctuating upward trend,with increases of 79.2%-87.4%after 15 FTCs,while dry-sieving aggregate(>2 mm)stability decreases significantly(5.7%-21.7%)upon the first FTC and remains unchanged thereafter.The stability of both the wet-and dry-sieving aggregates smaller than 2 mm remains unchanged with increasing FTCs(p>0.05).SOC content decreases by 22.3%on average with increasing FTCs from 1 to 15 and shows no significant correlations with wet-and dry-sieving aggregate stability.Higher silt content(r=0.39,p<0.05)and lower sand content(r=-0.38,p<0.05)enhances the wet-sieving aggregate stability of sandy loam.Frequent FTCs tend to improve wet-sieving aggregate stability but reduce dry-sieving aggregate stability in the sandy loam.The findings provide certain guidance for preventing freeze-thaw-induced wind erosion.
文摘Protein aggregates,mitochondrial import stress and neurodegenerative disorders:A salient hallmark of several neurodegenerative diseases,including Parkinson’s disease,is the abundance of protein aggregates(Goiran et al.,2022).This molecular event is believed to lead to activation of stress pathways ultimately resulting in cellular dysfunction(Eldeeb et al.,2022).Accordingly,many lines of research investigations focused on dampening the formation of protein aggregates or augmenting the clearance of protein aggregates as a potential therapeutic strategy to counteract the progression of neurodegenerative diseases,albeit with little success(Costa-Mattioli and Walter,2020).Cell stress cues such as the accumulation of protein aggregates lead to the activation of stress response pathways that aid cells in responding to the damage.Despite the notion that the transient activation of these pathways helps cells cope with stressors,persistent activation can induce unwanted apoptosis of cells and reduce overall tissue strength as well as lead to an accumulation of aggregation-prone proteins(Hetz and Papa,2018).Mutations in proteins involved in stress signaling termination can cause conditions like ataxia and early-onset dementia(Conroy et al.,2014).Therefore,it is crucial for stress response signaling to be turned off once conditions have improved.Nevertheless,the mechanisms by which cells silence these signals are still elusive.
