Prisoner’s Dilemma is a master trope for relaying the permanent impasse or dilemma of cooperation versus defection.In Prisoner’s Dilemma Richard Powers narrates a multiform of dilemma mainly narrating Eddie Hobson’...Prisoner’s Dilemma is a master trope for relaying the permanent impasse or dilemma of cooperation versus defection.In Prisoner’s Dilemma Richard Powers narrates a multiform of dilemma mainly narrating Eddie Hobson’s traumatic history,along with Eddie’s attempt to carry out a strategy—Eddie’s ideal Hobstown which is supposed to cope with the confused dilemma.Pow⁃ers’strategic moral insights are revealed by assuming that each player feels sympathy for the other and a moral cooperative instead of antagonistic solution to the Prisoner’s Dilemma will be found.展开更多
Without cooperative behaviors, our society or organization falls into social dilemma situations where every member selects uncooperative （defective） behaviors, and the situation gets worse and worse. Such a situatio...Without cooperative behaviors, our society or organization falls into social dilemma situations where every member selects uncooperative （defective） behaviors, and the situation gets worse and worse. Such a situation in a society or an organization leads to violation of social or organizational rules, and at the worst case it suffers from serious accidents or scandals. Therefore, it is important for us to make efforts and take measures to elicit cooperative behaviors. It was demonstrated theoretically that altruism strategy and adaptive prediction and ascertainment strategy are in some cases better than rational strategy under the situation of social dilemma. We built up a mathematical model in order to examine how the probability of correctly predicting and ascertaining the behavior （cooperation or defection） of opponents and the mixture of （a） altruism （all cooperation） strategy, （b） individualism （all defection） strategy, and （c） adaptive prediction and ascertainment strategy affected the expected profit. Simulation results showed that the tit-for-tat strategy was better than the rational （individualism） strategy when the probability of correctly predicting and ascertaining defection of the opponent was considerably higher. As an application of the basic study above, it was explored, using a simulation method, how such a system as opening reputation or peer review in public could work satisfactorily to prevent defective behaviors in auction dealing. The result showed that the information on the handle name and the reputation effectively worked to prevent defective behaviors.展开更多
In this study,we examine the problem of predicting customer defection in a noncontractual setting.Motivated by recent work on machine learning using multiple time slices,we develop a novel training and testing framewo...In this study,we examine the problem of predicting customer defection in a noncontractual setting.Motivated by recent work on machine learning using multiple time slices,we develop a novel training and testing framework,the sliding multi-time slicing(SMTS)method.We apply this method to data from the largest marketplace in Greece,namely,Skroutz,considering the standard features that account for the important characteristics of customer activity and custom performance metrics aimed at capturing business-related goals established by the company.The dataset comprises customers over a relatively short period,since April 2018,the number of which has also exhibited a significant increase in recent months.Despite these difficulties and the inherent seasonality of customer defection,our results demonstrate that,with SMTS,developing models that outperform previous approaches and optimize decision-making is possible.We validate the approach to a benchmark dataset from the commerce sector and discuss the practical considerations and requirements of the proposed method.展开更多
In our society, it is a major issue to enhance cooperative behaviors. Without this, our society fall into social dilemma situations, and gets worse and worse. Such a situation in an organization leads to violation of ...In our society, it is a major issue to enhance cooperative behaviors. Without this, our society fall into social dilemma situations, and gets worse and worse. Such a situation in an organization leads to violation of social or organizational rules, and at the worst case it suffers from serious accidents or scandals. Therefore, it is important for organizational managers to make efforts and take measures to enhance cooperative behaviors. Although there seem to be many ways to constantly elicit cooperative behaviors, the punishment is one of the most effective measures for enhancing cooperation. This study focused on the effects of penalty and probability of the revelation of defection on the cooperation, and getting insight into how punishment strategy should be used to get rid of social dilemmas and enhance cooperation. This study conducted a simulation experiment to find the proper penal regulations condition that can suppress violations （defective behavior） in a 2-person prisoner＇s dilemma situation. The effects of probability of the revelation of defection and penalty to revelation on the cooperative behavior were identified with the interactive effect of both experimental factors. The defection （uncooperative behavior） decreased when the penalty to the defection was heavy and the probability of the revelation of defection was low than that when the penalty to the defection was light and the probability of the revelation of the defection was high.展开更多
Based on inspection data,the authors analyze and summarize the main types and distribution characteristics of tunnel structural defects.These defects are classified into three types:surface defects,internal defects,an...Based on inspection data,the authors analyze and summarize the main types and distribution characteristics of tunnel structural defects.These defects are classified into three types:surface defects,internal defects,and defects behind the structure.To address the need for rapid detection of different defect types,the current state of rapid detection technologies and equipment,both domestically and internationally,is systematically reviewed.The research reveals that surface defect detection technologies and equipment have developed rapidly in recent years.Notably,the integration of machine vision and laser scanning technologies have significantly improved detection efficiency and accuracy,achieving crack detection precision of up to 0.1 mm.However,the non-contact rapid detection of internal and behind-the-structure defects remains constrained by hardware limitations,with traditional detection remaining dominant.Nevertheless,phased array radar,ultrasonic,and acoustic vibration detection technologies have become research hotspots in recent years,offering promising directions for detecting these challenging defect types.Additionally,the application of multisensor fusion technology in rapid detection equipment has further enhanced detection capabilities.Devices such as cameras,3D laser scanners,infrared thermal imagers,and radar demonstrate significant advantages in rapid detection.Future research in tunnel inspection should prioritize breakthroughs in rapid detection technologies for internal and behind-the-structure defects.Efforts should also focus on developing multifunctional integrated detection vehicles that can simultaneously inspect both surface and internal structures.Furthermore,progress in fully automated,intelligent systems with precise defect identification and real-time reporting will be essential to significantly improve the efficiency and accuracy of tunnel inspection.展开更多
Perovskite quantum dot light-emitting diodes(Pe-QLEDs)have shown immense application potential in display and lighting fields due to their narrow full-width at half maximum(FWHM)and high photoluminescence quantum yiel...Perovskite quantum dot light-emitting diodes(Pe-QLEDs)have shown immense application potential in display and lighting fields due to their narrow full-width at half maximum(FWHM)and high photoluminescence quantum yield(PLQY).Despite significant advancements in their performance,challenges such as defects and ion migration still hinder their long-term stability and operational efficiency.To address these issues,various optimization strategies,including ligand engineering,interface passivation,and self-assembly strategy,are being actively researched.This review focuses on the synthesis methods,challenges and optimization of perovskite quantum dots,which are critical for the commercialization and large-scale production of high-performance and stable Pe-QLEDs.展开更多
The scratching mechanism of polycrystallineγ-TiAl alloy was investigated at the atomic scale using the molecular dynamics method,with a focus on the influence of different grain sizes.The analysis encompassed tribolo...The scratching mechanism of polycrystallineγ-TiAl alloy was investigated at the atomic scale using the molecular dynamics method,with a focus on the influence of different grain sizes.The analysis encompassed tribological characteristics,scratch morphology,subsurface defect distribution,temperature variations,and stress states during the scratching process.The findings indicate that the scratch force,number of recovered atoms,and pile-up height exhibit abrupt changes when the critical size is 9.41 nm due to the influence of the inverse Hall-Petch effect.Variations in the number of grain boundaries and randomness of grain orientation result in different accumulation patterns on the scratch surface.Notably,single crystal materials and those with 3.73 nm in grain size display more regular surface morphology.Furthermore,smaller grain size leads to an increase in average coefficient of friction,removed atoms number,and wear rate.While it also causes higher temperatures with a larger range of distributions.Due to the barrier effect of grain boundaries,smaller grains exhibit reduced microscopic defects.Additionally,average von Mises stress and hydrostatic compressive stress at the indenter tip decrease as grain size decreases owing to grain boundary obstruction.展开更多
In integrated circuit(IC)manufacturing,fast,nondestructive,and precise detection of defects in patterned wafers,realized by bright-field microscopy,is one of the critical factors for ensuring the final performance and...In integrated circuit(IC)manufacturing,fast,nondestructive,and precise detection of defects in patterned wafers,realized by bright-field microscopy,is one of the critical factors for ensuring the final performance and yields of chips.With the critical dimensions of IC nanostructures continuing to shrink,directly imaging or classifying deep-subwavelength defects by bright-field microscopy is challenging due to the well-known diffraction barrier,the weak scattering effect,and the faint correlation between the scattering cross-section and the defect morphology.Herein,we propose an optical far-field inspection method based on the form-birefringence scattering imaging of the defective nanostructure,which can identify and classify various defects without requiring optical super-resolution.The technique is built upon the principle of breaking the optical form birefringence of the original periodic nanostructures by the defect perturbation under the anisotropic illumination modes,such as the orthogonally polarized plane waves,then combined with the high-order difference of far-field images.We validated the feasibility and effectiveness of the proposed method in detecting deep subwavelength defects through rigid vector imaging modeling and optical detection experiments of various defective nanostructures based on polarization microscopy.On this basis,an intelligent classification algorithm for typical patterned defects based on a dual-channel AlexNet neural network has been proposed,stabilizing the classification accuracy ofλ/16-sized defects with highly similar features at more than 90%.The strong classification capability of the two-channel network on typical patterned defects can be attributed to the high-order difference image and its transverse gradient being used as the network’s input,which highlights the polarization modulation difference between different patterned defects more significantly than conventional bright-field microscopy results.This work will provide a new but easy-to-operate method for detecting and classifying deep-subwavelength defects in patterned wafers or photomasks,which thus endows current online inspection equipment with more missions in advanced IC manufacturing.展开更多
Selective catalytic reduction of NO_(x) with CO(CO-SCR)is a process that purifies both NO and CO pollutants through a catalytic reaction.Specifically,the cleavage of NO on the catalyst surface is crucial for promoting...Selective catalytic reduction of NO_(x) with CO(CO-SCR)is a process that purifies both NO and CO pollutants through a catalytic reaction.Specifically,the cleavage of NO on the catalyst surface is crucial for promoting the reaction.During the reaction,the presence of oxygen vacancies can extract oxygen from NO,thereby facilitating the cleavage of NO on the catalyst surface.Thus,the formation of oxygen vacancies is key to accelerating the CO-SCR reaction,with different types of oxygen vacancies being more conducive to their generation.In this study,Rh/CeCuO_(x) catalysts were synthesized using the co-crystallization and impregnation methods,and asymmetric oxygen vacancies were induced through hydrogen thermal treatment.This structuralmodification was aimed at regulating the behavior of NO on the catalyst surface.The Rh/Ce0.95Cu0.05O_(x)-H_(2) catalyst exhibited the best performance in CO-SCR,achieving above 90%NO conversion at 162℃.Various characterization techniques showed that the H_(2) treatment effectively reduced some of the CuO and Rh_(2)O_(3),creating asymmetric oxygen vacancies that accelerated the cleavage of NO on the catalyst surface,rather than forming difficult-to-decompose nitrates.This study offers a novel approach to constructing oxygen vacancies in new CO-SCR catalysts.展开更多
Phenanthrene(Phe)is one of the common polycyclic aromatic hydrocarbons in the environment,and recent studies show that it can cause cardiac developmental toxicity and immunotoxicity.However,it is still unknown whether...Phenanthrene(Phe)is one of the common polycyclic aromatic hydrocarbons in the environment,and recent studies show that it can cause cardiac developmental toxicity and immunotoxicity.However,it is still unknown whether it can affect the hematopoietic development in aquatic organisms.To address this question,zebrafish(Danio rerio)were chronically exposed to Phe at different concentrations.We found that Phe caused structural damage to the renal tubules in the kidney,induced malformed erythrocytes in peripheral blood,and decreased the proportion of myeloid cells in adult zebrafish,suggesting possible negative impacts that Phe posed to hematopoietic development.Then,using in situ hybridization technology,we found that Phe decreased the expression of primitive hematopoietic marker genes,specifically gata1 and pu.1,accompanied by an obstruction of primitive erythrocyte circulation.Furthermore,Phe impaired definitive hematopoiesis,increased aberrations of the transient hematopoietic site(PBI),and reduced the generation of hematopoietic stem cells,ultimately influencing the number of erythrocytes and myeloid cells.The findings suggested that Phe could induce hematopoietic toxicity in zebrafish embryos and pose unknown ecological risks.展开更多
Background:Congenital heart disease(CHD)results from abnormal heart development during fetal development,leading to life-threatening complications.This study aimed to evaluate the feasibility of applying myocardial pa...Background:Congenital heart disease(CHD)results from abnormal heart development during fetal development,leading to life-threatening complications.This study aimed to evaluate the feasibility of applying myocardial parametric mapping in post-mortem magnetic resonance imaging and to examine differences in the left ventricular myocardium between fetuses with CHD and controls.Methods:This prospective case–control study was conducted on 14 deceased fetuses with CHD(CHD group)and 24 fetuses without CHD(control group).Fetuses with CHD were further stratified into the cyanotic(n=9)and non-cyanotic(n=5)CHD groups.T1,T2,and proton density relaxation times of the left ventricular myocardium were calculated and compared using multiple-dynamic multiple-echo post-mortem magnetic resonance imaging technology.Results:The myocardial T2 relaxation time was significantly different between the groups(p=0.033),with no difference in T1 or proton density relaxation times between the groups.A one-way analysis of variance with Tukey's test showed that the mean cyanotic CHD group showed a longer myocardial T2 relaxation time than the control group(98.00013.143 vs.83.5429.491 ms,p=0.003).Additionally,the correlation coefficient in the CHD group was significantly different between the myocardial T2 relaxation time and peak systolic velocity of pulmonary artery on a fetal echocardiogram(r2=0.681,p=0.010).Conclusions:These results suggest that using myocardial alterations in the T2 relaxation time may provide a accurate early warning for myocardial injury and enable noninvasive recognition of cardiac involvement in fetuses with CHD.展开更多
As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially ...As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially in the context of an imbalance between osteoblast and osteoclast activities.Therefore,the development of new biomaterials has become the key.This article reviews various design strategies and their advantages and disadvantages for biomaterials aimed at osteoporotic bone defects.Overall,current research progress indicates that innovative design,functionalization,and targeting of materials can significantly enhance bone regeneration under osteoporotic conditions.By comprehensively considering biocompatibility,mechanical properties,and bioactivity,these biomaterials can be further optimized,offering a range of choices and strategies for the repair of osteoporotic bone defects.展开更多
To solve the problem of low detection accuracy for complex weld defects,the paper proposes a weld defects detection method based on improved YOLOv5s.To enhance the ability to focus on key information in feature maps,t...To solve the problem of low detection accuracy for complex weld defects,the paper proposes a weld defects detection method based on improved YOLOv5s.To enhance the ability to focus on key information in feature maps,the scSE attention mechanism is intro-duced into the backbone network of YOLOv5s.A Fusion-Block module and additional layers are added to the neck network of YOLOv5s to improve the effect of feature fusion,which is to meet the needs of complex object detection.To reduce the computation-al complexity of the model,the C3Ghost module is used to replace the CSP2_1 module in the neck network of YOLOv5s.The scSE-ASFF module is constructed and inserted between the neck network and the prediction end,which is to realize the fusion of features between the different layers.To address the issue of imbalanced sample quality in the dataset and improve the regression speed and accuracy of the loss function,the CIoU loss function in the YOLOv5s model is replaced with the Focal-EIoU loss function.Finally,ex-periments are conducted based on the collected weld defect dataset to verify the feasibility of the improved YOLOv5s for weld defects detection.The experimental results show that the precision and mAP of the improved YOLOv5s in detecting complex weld defects are as high as 83.4%and 76.1%,respectively,which are 2.5%and 7.6%higher than the traditional YOLOv5s model.The proposed weld defects detection method based on the improved YOLOv5s in this paper can effectively solve the problem of low weld defects detection accuracy.展开更多
Through strategies such as process optimization,solvent selection,and component tuning,the crystallization of perovskite materials has been effectively controlled,enabling perovskite solar cells(PSCs)to achieve over 2...Through strategies such as process optimization,solvent selection,and component tuning,the crystallization of perovskite materials has been effectively controlled,enabling perovskite solar cells(PSCs)to achieve over 25%power conversion efficiency(PCE).However,as PCE continues to improve,interfacial issues within the devices have emerged as critical bottlenecks,hindering further performance enhancements.Recently,interfacial engineering has driven transformative progress,pushing PCEs to nearly 27%.Building upon these developments,this review first summarizes the pivotal role of interfacial modifications in elevating device performance and then,as a starting point,provides a comprehensive overview of recent advancements in normal,inverted,and tandem structure devices.Finally,based on the current progress of PSCs,preliminary perspectives on future directions are presented.展开更多
Ensuring the consistent mechanical performance of three-dimensional(3D)-printed continuous fiber-reinforced composites is a significant challenge in additive manufacturing.The current reliance on manual monitoring exa...Ensuring the consistent mechanical performance of three-dimensional(3D)-printed continuous fiber-reinforced composites is a significant challenge in additive manufacturing.The current reliance on manual monitoring exacerbates this challenge by rendering the process vulnerable to environmental changes and unexpected factors,resulting in defects and inconsistent product quality,particularly in unmanned long-term operations or printing in extreme environments.To address these issues,we developed a process monitoring and closed-loop feedback control strategy for the 3D printing process.Real-time printing image data were captured and analyzed using a well-trained neural network model,and a real-time control module-enabled closed-loop feedback control of the flow rate was developed.The neural network model,which was based on image processing and artificial intelligence,enabled the recognition of flow rate values with an accuracy of 94.70%.The experimental results showed significant improvements in both the surface performance and mechanical properties of printed composites,with three to six times improvement in tensile strength and elastic modulus,demonstrating the effectiveness of the strategy.This study provides a generalized process monitoring and feedback control method for the 3D printing of continuous fiber-reinforced composites,and offers a potential solution for remote online monitoring and closed-loop adjustment in unmanned or extreme space environments.展开更多
For realizing the goals of“carbon peak”and“carbon neutrality”,lithium-ion batteries(LIB)with LiFePO_(4)as the cathode material have been widely applied.However,this has also led to a large number of spent lithium-...For realizing the goals of“carbon peak”and“carbon neutrality”,lithium-ion batteries(LIB)with LiFePO_(4)as the cathode material have been widely applied.However,this has also led to a large number of spent lithium-ion batteries,and the safe disposal of spent lithium-ion batteries is an urgent issue.Currently,the main reason for the capacity decay of LiFePO_(4)materials is the Li deficiency and the formation of the Fe^(3+)phase.In order to address this issue,we performed high-temperature calcination of the discarded lithium iron phosphate cathode material in a carbon dioxide environment to reduce or partially remove the carbon coating on its surface.Subsequently,mechanical grinding was conducted to ensure thorough mixing of the lithium source with the discarded lithium iron phosphate.The reaction between CO_(2)and the carbon coating produced a reducing atmosphere,reducing Fe^(3+)to Fe^(2+)and thereby reducing the content of Fe^(3+).The Fe^(3+)content in the repaired LiFePO_(4)material is reduced.The crystal structure of spent LiFePO_(4)cathode materials was repaired more completely compare with the traditional pretreatment method,and the repaired LiFePO_(4)material shows good electrochemical performance and cycling stability.Under 0.1 C conditions,the initial capacity can reach 149.1 m Ah/g.It can be reintroduced for commercial use.展开更多
Manganese-based chalcogenides have significant potential as anodes for sodium-ion batteries(SIBs) due to their high theoretical specific capacity, abundant natural reserves, and environmental friendliness. However, th...Manganese-based chalcogenides have significant potential as anodes for sodium-ion batteries(SIBs) due to their high theoretical specific capacity, abundant natural reserves, and environmental friendliness. However, their application is hindered by poor cycling stability, resulting from severe volume changes during cycling and slow reaction kinetics due to their complex crystal structure. Here, an efficient and straightforward strategy was employed to in-situ encapsulate single-phase porous nanocubic MnS_(0.5)Se_(0.5) into carbon nanofibers using electrospinning and the hard template method, thus forming a necklace-like porous MnS_(0.5)Se_(0.5)-carbon nanofiber composite(MnS_(0.5)Se_(0.5)@N-CNF). The introduction of Se significantly impacts both the composition and microstructure of MnS_(0.5)Se_(0.5), including lattice distortion that generates additional defects, optimization of chemical bonds, and a nano-spatially confined design. In situ/ex-situ characterization and density functional theory calculations verified that this MnS_(0.5)Se_(0.5)@N-CNF allevi- ates the volume expansion and facilitates the transfer of Na+/electron. As expected, MnS_(0.5)Se_(0.5)@N-CNF anode demonstrates excellent sodium storage performance, characterized by high initial Coulombic efficiency(90.8%), high-rate capability(370.5 m Ahg^(-1) at 10 Ag^(-1)) and long durability(over 5000 cycles at 5 Ag^(-1)). The MnS_(0.5)Se_(0.5)@N-CNF//NVP@C full cell, assembled with MnS_(0.5)Se_(0.5)@N-CNF as anode and Na_(3)V_(2)(PO_4)_(3)@C as cathode, exhibits a high energy density of 254 Wh kg^(-1) can be provided. This work presents a novel strategy to optimize the design of anode materials through structural engineering and Se substitution, while also elucidating the underlying reaction mechanisms.展开更多
Point defect engineering endows catalysts with novel physical and chemical properties,elevating their electrocatalytic efficiency.The introduction of defects emerges as a promising strategy,effectively modifying the e...Point defect engineering endows catalysts with novel physical and chemical properties,elevating their electrocatalytic efficiency.The introduction of defects emerges as a promising strategy,effectively modifying the electronic structure of active sites.This optimization influences the adsorption energy of intermediates,thereby mitigating reaction energy barriers,altering paths,enhancing selectivity,and ultimately improving the catalytic efficiency of electrocatalysts.To elucidate the impact of defects on the electrocatalytic process,we comprehensively outline the roles of various point defects,their synthetic methodologies,and characterization techniques.Importantly,we consolidate insights into the relationship between point defects and catalytic activity for hydrogen/oxygen evolution and CO_(2)/O_(2)/N_(2) reduction reactions by integrating mechanisms from diverse reactions.This underscores the pivotal role of point defects in enhancing catalytic performance.At last,the principal challenges and prospects associated with point defects in current electrocatalysts are proposed,emphasizing their role in advancing the efficiency of electrochemical energy storage and conversion materials.展开更多
High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors.However,simultaneously excellent performances,inclu...High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors.However,simultaneously excellent performances,including high figure of merit(FOM),insulation resistivity(ρ)and depolarization temperature(Td)are indispensable but hard to achieve in lead-free piezoceramics,especially operating at 250°C has not been reported before.Herein,well-balanced performances are achieved in BiFeO3–BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese doping.Due to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization,regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole,comprehensive excellent electrical performances(Td=340°C,ρ250°C>10^(7)Ωcm and FOM_(250°C)=4905×10^(–15)m^(2)N^(−1))are realized at the solid solubility limit of manganese ions.The HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250°C with high energy conversion efficiency(η=11.43%).These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements,paving a new way in developing selfpowered wireless sensors working in HT environments.展开更多
文摘Prisoner’s Dilemma is a master trope for relaying the permanent impasse or dilemma of cooperation versus defection.In Prisoner’s Dilemma Richard Powers narrates a multiform of dilemma mainly narrating Eddie Hobson’s traumatic history,along with Eddie’s attempt to carry out a strategy—Eddie’s ideal Hobstown which is supposed to cope with the confused dilemma.Pow⁃ers’strategic moral insights are revealed by assuming that each player feels sympathy for the other and a moral cooperative instead of antagonistic solution to the Prisoner’s Dilemma will be found.
文摘Without cooperative behaviors, our society or organization falls into social dilemma situations where every member selects uncooperative （defective） behaviors, and the situation gets worse and worse. Such a situation in a society or an organization leads to violation of social or organizational rules, and at the worst case it suffers from serious accidents or scandals. Therefore, it is important for us to make efforts and take measures to elicit cooperative behaviors. It was demonstrated theoretically that altruism strategy and adaptive prediction and ascertainment strategy are in some cases better than rational strategy under the situation of social dilemma. We built up a mathematical model in order to examine how the probability of correctly predicting and ascertaining the behavior （cooperation or defection） of opponents and the mixture of （a） altruism （all cooperation） strategy, （b） individualism （all defection） strategy, and （c） adaptive prediction and ascertainment strategy affected the expected profit. Simulation results showed that the tit-for-tat strategy was better than the rational （individualism） strategy when the probability of correctly predicting and ascertaining defection of the opponent was considerably higher. As an application of the basic study above, it was explored, using a simulation method, how such a system as opening reputation or peer review in public could work satisfactorily to prevent defective behaviors in auction dealing. The result showed that the information on the handle name and the reputation effectively worked to prevent defective behaviors.
文摘In this study,we examine the problem of predicting customer defection in a noncontractual setting.Motivated by recent work on machine learning using multiple time slices,we develop a novel training and testing framework,the sliding multi-time slicing(SMTS)method.We apply this method to data from the largest marketplace in Greece,namely,Skroutz,considering the standard features that account for the important characteristics of customer activity and custom performance metrics aimed at capturing business-related goals established by the company.The dataset comprises customers over a relatively short period,since April 2018,the number of which has also exhibited a significant increase in recent months.Despite these difficulties and the inherent seasonality of customer defection,our results demonstrate that,with SMTS,developing models that outperform previous approaches and optimize decision-making is possible.We validate the approach to a benchmark dataset from the commerce sector and discuss the practical considerations and requirements of the proposed method.
文摘In our society, it is a major issue to enhance cooperative behaviors. Without this, our society fall into social dilemma situations, and gets worse and worse. Such a situation in an organization leads to violation of social or organizational rules, and at the worst case it suffers from serious accidents or scandals. Therefore, it is important for organizational managers to make efforts and take measures to enhance cooperative behaviors. Although there seem to be many ways to constantly elicit cooperative behaviors, the punishment is one of the most effective measures for enhancing cooperation. This study focused on the effects of penalty and probability of the revelation of defection on the cooperation, and getting insight into how punishment strategy should be used to get rid of social dilemmas and enhance cooperation. This study conducted a simulation experiment to find the proper penal regulations condition that can suppress violations （defective behavior） in a 2-person prisoner＇s dilemma situation. The effects of probability of the revelation of defection and penalty to revelation on the cooperative behavior were identified with the interactive effect of both experimental factors. The defection （uncooperative behavior） decreased when the penalty to the defection was heavy and the probability of the revelation of defection was low than that when the penalty to the defection was light and the probability of the revelation of the defection was high.
文摘Based on inspection data,the authors analyze and summarize the main types and distribution characteristics of tunnel structural defects.These defects are classified into three types:surface defects,internal defects,and defects behind the structure.To address the need for rapid detection of different defect types,the current state of rapid detection technologies and equipment,both domestically and internationally,is systematically reviewed.The research reveals that surface defect detection technologies and equipment have developed rapidly in recent years.Notably,the integration of machine vision and laser scanning technologies have significantly improved detection efficiency and accuracy,achieving crack detection precision of up to 0.1 mm.However,the non-contact rapid detection of internal and behind-the-structure defects remains constrained by hardware limitations,with traditional detection remaining dominant.Nevertheless,phased array radar,ultrasonic,and acoustic vibration detection technologies have become research hotspots in recent years,offering promising directions for detecting these challenging defect types.Additionally,the application of multisensor fusion technology in rapid detection equipment has further enhanced detection capabilities.Devices such as cameras,3D laser scanners,infrared thermal imagers,and radar demonstrate significant advantages in rapid detection.Future research in tunnel inspection should prioritize breakthroughs in rapid detection technologies for internal and behind-the-structure defects.Efforts should also focus on developing multifunctional integrated detection vehicles that can simultaneously inspect both surface and internal structures.Furthermore,progress in fully automated,intelligent systems with precise defect identification and real-time reporting will be essential to significantly improve the efficiency and accuracy of tunnel inspection.
文摘Perovskite quantum dot light-emitting diodes(Pe-QLEDs)have shown immense application potential in display and lighting fields due to their narrow full-width at half maximum(FWHM)and high photoluminescence quantum yield(PLQY).Despite significant advancements in their performance,challenges such as defects and ion migration still hinder their long-term stability and operational efficiency.To address these issues,various optimization strategies,including ligand engineering,interface passivation,and self-assembly strategy,are being actively researched.This review focuses on the synthesis methods,challenges and optimization of perovskite quantum dots,which are critical for the commercialization and large-scale production of high-performance and stable Pe-QLEDs.
基金National Natural Science Foundation of China(52065036,52365018)Natural Science Foundation of Gansu(23JRRA760)+1 种基金Hongliu Outstanding Youth Foundation of Lanzhou University of TechnologyChina Postdoctoral Science Foundation(2023M733583)。
文摘The scratching mechanism of polycrystallineγ-TiAl alloy was investigated at the atomic scale using the molecular dynamics method,with a focus on the influence of different grain sizes.The analysis encompassed tribological characteristics,scratch morphology,subsurface defect distribution,temperature variations,and stress states during the scratching process.The findings indicate that the scratch force,number of recovered atoms,and pile-up height exhibit abrupt changes when the critical size is 9.41 nm due to the influence of the inverse Hall-Petch effect.Variations in the number of grain boundaries and randomness of grain orientation result in different accumulation patterns on the scratch surface.Notably,single crystal materials and those with 3.73 nm in grain size display more regular surface morphology.Furthermore,smaller grain size leads to an increase in average coefficient of friction,removed atoms number,and wear rate.While it also causes higher temperatures with a larger range of distributions.Due to the barrier effect of grain boundaries,smaller grains exhibit reduced microscopic defects.Additionally,average von Mises stress and hydrostatic compressive stress at the indenter tip decrease as grain size decreases owing to grain boundary obstruction.
基金funded by National Natural Science Foundation of China(Grant Nos.52130504,52305577,and 52175509)the Key Research and Development Plan of Hubei Province(Grant No.2022BAA013)+4 种基金the Major Program(JD)of Hubei Province(Grant No.2023BAA008-2)the Interdisciplinary Research Program of Huazhong University of Science and Technology(2023JCYJ047)the Innovation Project of Optics Valley Laboratory(Grant No.OVL2023PY003)the Postdoctoral Fellowship Program(Grade B)of China Postdoctoral Science Foundation(Grant No.GZB20230244)the fellowship from the China Postdoctoral Science Foundation(2024M750995)。
文摘In integrated circuit(IC)manufacturing,fast,nondestructive,and precise detection of defects in patterned wafers,realized by bright-field microscopy,is one of the critical factors for ensuring the final performance and yields of chips.With the critical dimensions of IC nanostructures continuing to shrink,directly imaging or classifying deep-subwavelength defects by bright-field microscopy is challenging due to the well-known diffraction barrier,the weak scattering effect,and the faint correlation between the scattering cross-section and the defect morphology.Herein,we propose an optical far-field inspection method based on the form-birefringence scattering imaging of the defective nanostructure,which can identify and classify various defects without requiring optical super-resolution.The technique is built upon the principle of breaking the optical form birefringence of the original periodic nanostructures by the defect perturbation under the anisotropic illumination modes,such as the orthogonally polarized plane waves,then combined with the high-order difference of far-field images.We validated the feasibility and effectiveness of the proposed method in detecting deep subwavelength defects through rigid vector imaging modeling and optical detection experiments of various defective nanostructures based on polarization microscopy.On this basis,an intelligent classification algorithm for typical patterned defects based on a dual-channel AlexNet neural network has been proposed,stabilizing the classification accuracy ofλ/16-sized defects with highly similar features at more than 90%.The strong classification capability of the two-channel network on typical patterned defects can be attributed to the high-order difference image and its transverse gradient being used as the network’s input,which highlights the polarization modulation difference between different patterned defects more significantly than conventional bright-field microscopy results.This work will provide a new but easy-to-operate method for detecting and classifying deep-subwavelength defects in patterned wafers or photomasks,which thus endows current online inspection equipment with more missions in advanced IC manufacturing.
基金supported by the support of the National Natural Science Foundation of China(Nos.22072141,22176185 and 52304429)the National Key Research and Development Program of China(Nos.2022YFB3504200,2021YFB3501900)+4 种基金the Natural Science Foundation of Jiangxi Province for Distinguished Young Scholars(No.20232ACB213004)Jiangxi Provincial Key Research and Development Program(No.20232BBG70012)Jiangxi Provincial Natural Science Foundation(No.20212BAB213032)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2018263)the Research Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences(No.E355C001).
文摘Selective catalytic reduction of NO_(x) with CO(CO-SCR)is a process that purifies both NO and CO pollutants through a catalytic reaction.Specifically,the cleavage of NO on the catalyst surface is crucial for promoting the reaction.During the reaction,the presence of oxygen vacancies can extract oxygen from NO,thereby facilitating the cleavage of NO on the catalyst surface.Thus,the formation of oxygen vacancies is key to accelerating the CO-SCR reaction,with different types of oxygen vacancies being more conducive to their generation.In this study,Rh/CeCuO_(x) catalysts were synthesized using the co-crystallization and impregnation methods,and asymmetric oxygen vacancies were induced through hydrogen thermal treatment.This structuralmodification was aimed at regulating the behavior of NO on the catalyst surface.The Rh/Ce0.95Cu0.05O_(x)-H_(2) catalyst exhibited the best performance in CO-SCR,achieving above 90%NO conversion at 162℃.Various characterization techniques showed that the H_(2) treatment effectively reduced some of the CuO and Rh_(2)O_(3),creating asymmetric oxygen vacancies that accelerated the cleavage of NO on the catalyst surface,rather than forming difficult-to-decompose nitrates.This study offers a novel approach to constructing oxygen vacancies in new CO-SCR catalysts.
基金supported by the National Natural Science Foundation of China(Nos.22276117 and 22076108)the Science and Technology Innovation Talent Team Project of Shanxi Province(No.202204051002024).
文摘Phenanthrene(Phe)is one of the common polycyclic aromatic hydrocarbons in the environment,and recent studies show that it can cause cardiac developmental toxicity and immunotoxicity.However,it is still unknown whether it can affect the hematopoietic development in aquatic organisms.To address this question,zebrafish(Danio rerio)were chronically exposed to Phe at different concentrations.We found that Phe caused structural damage to the renal tubules in the kidney,induced malformed erythrocytes in peripheral blood,and decreased the proportion of myeloid cells in adult zebrafish,suggesting possible negative impacts that Phe posed to hematopoietic development.Then,using in situ hybridization technology,we found that Phe decreased the expression of primitive hematopoietic marker genes,specifically gata1 and pu.1,accompanied by an obstruction of primitive erythrocyte circulation.Furthermore,Phe impaired definitive hematopoiesis,increased aberrations of the transient hematopoietic site(PBI),and reduced the generation of hematopoietic stem cells,ultimately influencing the number of erythrocytes and myeloid cells.The findings suggested that Phe could induce hematopoietic toxicity in zebrafish embryos and pose unknown ecological risks.
基金supported by Zhejiang Provincial Natural Science Foundation of China(Grant/Award number:ZCLTGY24H0401)Education Department of Zhejiang Province(Grant/Award number:Y202352970).
文摘Background:Congenital heart disease(CHD)results from abnormal heart development during fetal development,leading to life-threatening complications.This study aimed to evaluate the feasibility of applying myocardial parametric mapping in post-mortem magnetic resonance imaging and to examine differences in the left ventricular myocardium between fetuses with CHD and controls.Methods:This prospective case–control study was conducted on 14 deceased fetuses with CHD(CHD group)and 24 fetuses without CHD(control group).Fetuses with CHD were further stratified into the cyanotic(n=9)and non-cyanotic(n=5)CHD groups.T1,T2,and proton density relaxation times of the left ventricular myocardium were calculated and compared using multiple-dynamic multiple-echo post-mortem magnetic resonance imaging technology.Results:The myocardial T2 relaxation time was significantly different between the groups(p=0.033),with no difference in T1 or proton density relaxation times between the groups.A one-way analysis of variance with Tukey's test showed that the mean cyanotic CHD group showed a longer myocardial T2 relaxation time than the control group(98.00013.143 vs.83.5429.491 ms,p=0.003).Additionally,the correlation coefficient in the CHD group was significantly different between the myocardial T2 relaxation time and peak systolic velocity of pulmonary artery on a fetal echocardiogram(r2=0.681,p=0.010).Conclusions:These results suggest that using myocardial alterations in the T2 relaxation time may provide a accurate early warning for myocardial injury and enable noninvasive recognition of cardiac involvement in fetuses with CHD.
基金supported by the National Natural Science Foundation of China(Nos.82160419 and 82302772)Guizhou Basic Research Project(No.ZK[2023]General 201)。
文摘As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially in the context of an imbalance between osteoblast and osteoclast activities.Therefore,the development of new biomaterials has become the key.This article reviews various design strategies and their advantages and disadvantages for biomaterials aimed at osteoporotic bone defects.Overall,current research progress indicates that innovative design,functionalization,and targeting of materials can significantly enhance bone regeneration under osteoporotic conditions.By comprehensively considering biocompatibility,mechanical properties,and bioactivity,these biomaterials can be further optimized,offering a range of choices and strategies for the repair of osteoporotic bone defects.
基金supported by Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX24_4084).
文摘To solve the problem of low detection accuracy for complex weld defects,the paper proposes a weld defects detection method based on improved YOLOv5s.To enhance the ability to focus on key information in feature maps,the scSE attention mechanism is intro-duced into the backbone network of YOLOv5s.A Fusion-Block module and additional layers are added to the neck network of YOLOv5s to improve the effect of feature fusion,which is to meet the needs of complex object detection.To reduce the computation-al complexity of the model,the C3Ghost module is used to replace the CSP2_1 module in the neck network of YOLOv5s.The scSE-ASFF module is constructed and inserted between the neck network and the prediction end,which is to realize the fusion of features between the different layers.To address the issue of imbalanced sample quality in the dataset and improve the regression speed and accuracy of the loss function,the CIoU loss function in the YOLOv5s model is replaced with the Focal-EIoU loss function.Finally,ex-periments are conducted based on the collected weld defect dataset to verify the feasibility of the improved YOLOv5s for weld defects detection.The experimental results show that the precision and mAP of the improved YOLOv5s in detecting complex weld defects are as high as 83.4%and 76.1%,respectively,which are 2.5%and 7.6%higher than the traditional YOLOv5s model.The proposed weld defects detection method based on the improved YOLOv5s in this paper can effectively solve the problem of low weld defects detection accuracy.
基金supported by National Natural Science Foundation of China(52302229,62404072)the Key Lab of Modern Optical Technologies of Education Ministry of China,Soochow University(KJS2425)+1 种基金Doctoral Foundation of Henan Polytech-nic University(B2024-72)Science and Technology Research Project of Jiangxi Provincial Department of Education(Grant No.GJJ2400702).
文摘Through strategies such as process optimization,solvent selection,and component tuning,the crystallization of perovskite materials has been effectively controlled,enabling perovskite solar cells(PSCs)to achieve over 25%power conversion efficiency(PCE).However,as PCE continues to improve,interfacial issues within the devices have emerged as critical bottlenecks,hindering further performance enhancements.Recently,interfacial engineering has driven transformative progress,pushing PCEs to nearly 27%.Building upon these developments,this review first summarizes the pivotal role of interfacial modifications in elevating device performance and then,as a starting point,provides a comprehensive overview of recent advancements in normal,inverted,and tandem structure devices.Finally,based on the current progress of PSCs,preliminary perspectives on future directions are presented.
基金supported by National Key Research and Development Program of China(Grant No.2023YFB4604100)National Key Research and Development Program of China(Grant No.2022YFB3806104)+4 种基金Key Research and Development Program in Shaanxi Province(Grant No.2021LLRH-08-17)Young Elite Scientists Sponsorship Program by CAST(No.2023QNRC001)K C Wong Education Foundation of ChinaYouth Innovation Team of Shaanxi Universities of ChinaKey Research and Development Program of Shaanxi Province(Grant 2021LLRH-08-3.1).
文摘Ensuring the consistent mechanical performance of three-dimensional(3D)-printed continuous fiber-reinforced composites is a significant challenge in additive manufacturing.The current reliance on manual monitoring exacerbates this challenge by rendering the process vulnerable to environmental changes and unexpected factors,resulting in defects and inconsistent product quality,particularly in unmanned long-term operations or printing in extreme environments.To address these issues,we developed a process monitoring and closed-loop feedback control strategy for the 3D printing process.Real-time printing image data were captured and analyzed using a well-trained neural network model,and a real-time control module-enabled closed-loop feedback control of the flow rate was developed.The neural network model,which was based on image processing and artificial intelligence,enabled the recognition of flow rate values with an accuracy of 94.70%.The experimental results showed significant improvements in both the surface performance and mechanical properties of printed composites,with three to six times improvement in tensile strength and elastic modulus,demonstrating the effectiveness of the strategy.This study provides a generalized process monitoring and feedback control method for the 3D printing of continuous fiber-reinforced composites,and offers a potential solution for remote online monitoring and closed-loop adjustment in unmanned or extreme space environments.
基金supported by Heilongjiang Province Key R&D Program(No.GA22A014)。
文摘For realizing the goals of“carbon peak”and“carbon neutrality”,lithium-ion batteries(LIB)with LiFePO_(4)as the cathode material have been widely applied.However,this has also led to a large number of spent lithium-ion batteries,and the safe disposal of spent lithium-ion batteries is an urgent issue.Currently,the main reason for the capacity decay of LiFePO_(4)materials is the Li deficiency and the formation of the Fe^(3+)phase.In order to address this issue,we performed high-temperature calcination of the discarded lithium iron phosphate cathode material in a carbon dioxide environment to reduce or partially remove the carbon coating on its surface.Subsequently,mechanical grinding was conducted to ensure thorough mixing of the lithium source with the discarded lithium iron phosphate.The reaction between CO_(2)and the carbon coating produced a reducing atmosphere,reducing Fe^(3+)to Fe^(2+)and thereby reducing the content of Fe^(3+).The Fe^(3+)content in the repaired LiFePO_(4)material is reduced.The crystal structure of spent LiFePO_(4)cathode materials was repaired more completely compare with the traditional pretreatment method,and the repaired LiFePO_(4)material shows good electrochemical performance and cycling stability.Under 0.1 C conditions,the initial capacity can reach 149.1 m Ah/g.It can be reintroduced for commercial use.
基金financially supported by the National Natural Science Foundation of China (No. 22225902, U22A20436, 22209185)National Key Research&Development Program of China (2022YFE0115900, 2023YFA1507101, 2021YFA1501500)+1 种基金the Self-deployment Project Research Program of Haixi Institutes,Chinese Academy of Sciences (No. CXZX-2022-GH04, CXZX-2023-JQ08)Science and Technology Program of Fuzhou (2023-P-009)。
文摘Manganese-based chalcogenides have significant potential as anodes for sodium-ion batteries(SIBs) due to their high theoretical specific capacity, abundant natural reserves, and environmental friendliness. However, their application is hindered by poor cycling stability, resulting from severe volume changes during cycling and slow reaction kinetics due to their complex crystal structure. Here, an efficient and straightforward strategy was employed to in-situ encapsulate single-phase porous nanocubic MnS_(0.5)Se_(0.5) into carbon nanofibers using electrospinning and the hard template method, thus forming a necklace-like porous MnS_(0.5)Se_(0.5)-carbon nanofiber composite(MnS_(0.5)Se_(0.5)@N-CNF). The introduction of Se significantly impacts both the composition and microstructure of MnS_(0.5)Se_(0.5), including lattice distortion that generates additional defects, optimization of chemical bonds, and a nano-spatially confined design. In situ/ex-situ characterization and density functional theory calculations verified that this MnS_(0.5)Se_(0.5)@N-CNF allevi- ates the volume expansion and facilitates the transfer of Na+/electron. As expected, MnS_(0.5)Se_(0.5)@N-CNF anode demonstrates excellent sodium storage performance, characterized by high initial Coulombic efficiency(90.8%), high-rate capability(370.5 m Ahg^(-1) at 10 Ag^(-1)) and long durability(over 5000 cycles at 5 Ag^(-1)). The MnS_(0.5)Se_(0.5)@N-CNF//NVP@C full cell, assembled with MnS_(0.5)Se_(0.5)@N-CNF as anode and Na_(3)V_(2)(PO_4)_(3)@C as cathode, exhibits a high energy density of 254 Wh kg^(-1) can be provided. This work presents a novel strategy to optimize the design of anode materials through structural engineering and Se substitution, while also elucidating the underlying reaction mechanisms.
基金supported by the National Natural Science Foundation of China(U21A20281)the Special Fund for Young Teachers from Zhengzhou University(JC23557030,JC23257011)+1 种基金the Key Research Projects of Higher Education Institutions of Henan Province(24A530009)the Project of Zhongyuan Critical Metals Laboratory(GJJSGFYQ202336).
文摘Point defect engineering endows catalysts with novel physical and chemical properties,elevating their electrocatalytic efficiency.The introduction of defects emerges as a promising strategy,effectively modifying the electronic structure of active sites.This optimization influences the adsorption energy of intermediates,thereby mitigating reaction energy barriers,altering paths,enhancing selectivity,and ultimately improving the catalytic efficiency of electrocatalysts.To elucidate the impact of defects on the electrocatalytic process,we comprehensively outline the roles of various point defects,their synthetic methodologies,and characterization techniques.Importantly,we consolidate insights into the relationship between point defects and catalytic activity for hydrogen/oxygen evolution and CO_(2)/O_(2)/N_(2) reduction reactions by integrating mechanisms from diverse reactions.This underscores the pivotal role of point defects in enhancing catalytic performance.At last,the principal challenges and prospects associated with point defects in current electrocatalysts are proposed,emphasizing their role in advancing the efficiency of electrochemical energy storage and conversion materials.
基金supported by the National Natural Science Foundation of China(Grant Nos.52272103 and 52072010)Beijing Natural Science Foundation(Grant Nos.2242029 and JL23004).
文摘High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors.However,simultaneously excellent performances,including high figure of merit(FOM),insulation resistivity(ρ)and depolarization temperature(Td)are indispensable but hard to achieve in lead-free piezoceramics,especially operating at 250°C has not been reported before.Herein,well-balanced performances are achieved in BiFeO3–BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese doping.Due to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization,regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole,comprehensive excellent electrical performances(Td=340°C,ρ250°C>10^(7)Ωcm and FOM_(250°C)=4905×10^(–15)m^(2)N^(−1))are realized at the solid solubility limit of manganese ions.The HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250°C with high energy conversion efficiency(η=11.43%).These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements,paving a new way in developing selfpowered wireless sensors working in HT environments.
