近年来,大语言模型(Large Language Models,LLMs)在情感对话中展现了令人惊叹的能力,并且在实现目标方面表现出较强的能力。然而,现有研究主要集中在通过情感共鸣式的回复提供安慰,而不是通过这些回复实现特定的现实目标。为了填补这一...近年来,大语言模型(Large Language Models,LLMs)在情感对话中展现了令人惊叹的能力,并且在实现目标方面表现出较强的能力。然而,现有研究主要集中在通过情感共鸣式的回复提供安慰,而不是通过这些回复实现特定的现实目标。为了填补这一研究空白,提出了一个名为SPEAKSMART的基准,其涵盖5个场景,用于评测LLMs在对话中通过高度共情的回复实现现实目标的能力。随后,引入了一个基于提供者满意度和请求者满意度的二维评测框架。利用SPEAKSMART对多种LLMs进行了评测,并设计了基线方法,以增强其在对话中生成具有说服力的共情回复的能力。实验结果表明,Claude3和LLaMA3-70B在不同场景中的表现最佳,而其他LLMs则有提升空间,这为增强LLMs处理需要高度共情回复以实现目标的现实任务的能力奠定了基础。展开更多
The corrosion behavior and microstructure characteristics of metal inert gas(MIG)welded dissimilar joints of the 6005A alloy modified with Sc(designated as 6005A+Sc)and the 5083 alloy were investigated using corrosion...The corrosion behavior and microstructure characteristics of metal inert gas(MIG)welded dissimilar joints of the 6005A alloy modified with Sc(designated as 6005A+Sc)and the 5083 alloy were investigated using corrosion tests and microscopy techniques.Results show that the dissimilar joints exhibit strong stress corrosion cracking(SCC)resistance,maintaining substantial strength during slow strain rate tensile tests.Notably,the heat-affected zone(HAZ)and base metal(BM)on the 6005A+Sc side show superior performance in terms of inter-granular corrosion(IGC)and exfoliation corrosion(EXCO)compared to the corresponding zones on the 5083 side.The lower corrosion resistance of the 5083-BM and the 5083-HAZ can be attributed to the presence of numerous Al_(2)Mg_(3)phases and micro-scaled Al_(6)(Mn,Fe)intermetallics,mainly distributed along the rolling direction.Conversely,the enhanced corrosion resistance of the 6005A+Sc-BM and the 6005A+Sc-HAZ can be attributed to the discontinuously distributed grain boundary precipitates(β-Mg_(2)Si),the smaller grain size,and the reduced corrosive current density.展开更多
On September 5,2022,at least 10,855 landslides had been triggered by a magnitude Mw 6.7(Ms 6.8)earthquake on the eastern margin of the Tibetan Plateau.Unfortunately,a detailed analysis of the spatial patterns of lands...On September 5,2022,at least 10,855 landslides had been triggered by a magnitude Mw 6.7(Ms 6.8)earthquake on the eastern margin of the Tibetan Plateau.Unfortunately,a detailed analysis of the spatial patterns of landslides in the eastern margin of the Baryan Har block is lacking.The observations show that the highest landslide concentrations are distributed along the seismogenic fault(Moxi fault)and Dadu River valley,coinciding with the effects of the hanging wall and microepicenter.Seismogenic tectonics controlled the regional distribution of new landslides,and the local topography influenced the detailed positions on the slopes.The total landslide mass wasting volume was 223.1×10^(6)m^(3),and the maximum occurred in the Wandong Basin(value of 74×10^(6)m^(3)).Thirty landslide dams were temporarily existing.Although some local collapses occurred at the toe of the Hailuogou glacier,seismic shaking had no obvious influence on the overall stability of the glacier.A post debris flow assessment indicates that some large basins contained much loose material and that some steep small basins had high debris flow susceptibility.On the eastern margin of the Bayan Har block,the landslide-triggering thrust and strike-slip events both follow the distributions of the hanging wall.展开更多
This study selected 45 A-share listed companies that have paid dividends for five consecutive years from 2019 to 2024,with an average dividend yield of at least 3%,as the sample.Using a panel data model,the effect of ...This study selected 45 A-share listed companies that have paid dividends for five consecutive years from 2019 to 2024,with an average dividend yield of at least 3%,as the sample.Using a panel data model,the effect of the cash dividend ratio on stock pricing was analyzed.The empirical results indicated a significant positive relationship between the cash dividend ratio and stock price.Furthermore,stocks with high dividend payouts demonstrated greater resilience during macroeconomic downturns,while notable differences were observed across industries.These findings provide a theoretical foundation for investors in making informed decisions and offer practical guidance for listed companies in formulating effective dividend policies.展开更多
This study employs leadership contingency theory and resource dependency theory,utilizing financial data from Shanghai and Shenzhen A-share listed companies between 2012 and 2021.Ultimately,data samples from 4,742 com...This study employs leadership contingency theory and resource dependency theory,utilizing financial data from Shanghai and Shenzhen A-share listed companies between 2012 and 2021.Ultimately,data samples from 4,742 companies were selected to empirically examine the impact and moderating role of female executives on corporate digital transformation.Findings reveal that the proportion of female executives positively promotes corporate digital transformation.Further analysis indicates that female executives drive digital transformation by enhancing corporate innovation investment and risk control capabilities.Supported by the heterogeneity analysis,it shows that this effect is more pronounced in high-tech industries,non-state-owned enterprises,and companies in economically developed regions.This study provides a gender-perspective theoretical explanation for the drivers of digital transformation and offers practical insights for optimizing corporate executive teams.展开更多
Unmanned Aerial Vehicles(UAVs)have been considered to have great potential in supporting reliable and timely data harvesting for Sensor Nodes(SNs)from an Internet of Things(IoT)perspective.However,due to physical limi...Unmanned Aerial Vehicles(UAVs)have been considered to have great potential in supporting reliable and timely data harvesting for Sensor Nodes(SNs)from an Internet of Things(IoT)perspective.However,due to physical limitations,UAVs are unable to further process the harvested data and have to rely on terrestrial servers,thus extra spectrum resource is needed to convey the harvested data.To avoid the cost of extra servers and spectrum resources,in this paper,we consider a UAV-based data harvesting network supported by a Cell-Free massive Multiple-Input-Multiple-Output(CF-mMIMO)system,where a UAV is used to collect and transmit data from SNs to the central processing unit of CF-mMIMO system for processing.In order to avoid using additional spectrum resources,the entire bandwidth is shared among radio access networks and wireless fronthaul links.Moreover,considering the limited capacity of the fronthaul links,the compress-and-forward scheme is adopted.In this work,in order to maximize the ergodically achievable sum rate of SNs,the power allocation of ground access points,the compression of fronthaul links,and also the bandwidth fraction between radio access networks and wireless fronthaul links are jointly optimized.To avoid the high overhead introduced by computing ergodically achievable rates,we introduce an approximate problem,using the large-dimensional random matrix theory,which relies only on statistical channel state information.We solve the nontrivial problem in three steps and propose an algorithm based on weighted minimum mean square error and Dinkelbach’s methods to find solutions.Finally,simulation results show that the proposed algorithm converges quickly and outperforms the baseline algorithms.展开更多
In semiconductor precision packaging and other applications involving alignment of automated equipment,the nonlinear motion caused by structural characteristics and friction effects on torque-type rotating motion stag...In semiconductor precision packaging and other applications involving alignment of automated equipment,the nonlinear motion caused by structural characteristics and friction effects on torque-type rotating motion stages seriously affects output accuracy and stability.To solve this problem,the motion characteristics of a rotating stage and the mechanism by which friction nonlinearity influences accuracy are analyzed in detail.In addition,a compound control strategy based on a kinematic model and the Stribeck friction model is designed.A friction disturbance observer based on output position feedback is improved for simple parameter tuning.Finally,an experimental system is constructed to carry out validation tests,including identification of nonlinear characteristics and performance comparisons.The experimental results show that the linear tracking error of the torque-type rotating stage is less than 1.47µm after adoption of the proposed model-based composite control strategy,and the corresponding rotary angle deviation is less than 0.0153°.The linearity of output motion is increased to 97.59%and the error compensation effect is improved by 51.6%compared with the PID control method.The experimental results confirm that the analysis method adopted here and the proposed compensation strategy can effectively reduce frictional nonlinearity and improve motion accuracy.The proposed method can also be applied to other precision electromechanical systems.展开更多
Current research on robot calibration can be roughly classified into two categories,and both of them have certain inherent limitations.Model-based methods are difficult to model and compensate the pose errors arising ...Current research on robot calibration can be roughly classified into two categories,and both of them have certain inherent limitations.Model-based methods are difficult to model and compensate the pose errors arising from configuration-dependent geometric and non-geometric source errors,whereas the accuracy of data-driven methods depends on a large amount of measurement data.Using a 5-DOF(degrees of freedom)hybrid machining robot as an exemplar,this study presents a model data-driven approach for the calibration of robotic manipulators.An f-DOF realistic robot containing various source errors is visualized as a 6-DOF fictitious robot having error-free parameters,but erroneous actuated/virtual joint motions.The calibration process essentially involves four steps:(1)formulating the linear map relating the pose error twist to the joint motion errors,(2)parameterizing the joint motion errors using second-order polynomials in terms of nominal actuated joint variables,(3)identifying the polynomial coefficients using the weighted least squares plus principal component analysis,and(4)compensating the compensable pose errors by updating the nominal actuated joint variables.The merit of this approach is that it enables compensation of the pose errors caused by configuration-dependent geometric and non-geometric source errors using finite measurement configurations.Experimental studies on a prototype machine illustrate the effectiveness of the proposed approach.展开更多
As emerging pollutants,microplastics have recently received considerable attention owing to detection in various organisms and environments.Mass production and widespread use of plastic products increase their potenti...As emerging pollutants,microplastics have recently received considerable attention owing to detection in various organisms and environments.Mass production and widespread use of plastic products increase their potential risks to humans owing to their persistent,mobile,and toxic properties.Numerous methods have been used to identify and quantify the various forms of microplastics,however,unified standards do not exist.In this review,we systematically summarize the sources,migration,transformation,and analytical methods for microplastics in diverse ecosystems,particularly the most recent sampling and identification techniques.Additionally,the environmental effects and health hazards of microplastics on aquatic and terrestrial systems,as well as human beings are discussed.We also present management strategies for reducing microplastics in a broader social and policy context.This review aims to provide an overview of the migration,transformation,sampling,analysis,and environmental effects of microplastics,which addresses knowledge gaps in microplastic pollution and provides proposals for key research gaps.展开更多
文摘【目的】了解植物枝叶性状间的权衡关系,为进一步揭示植物在不同环境胁迫下采取的资源分配策略提供参考。【方法】以原始阔叶红松(Pinus koraiensis)林中的优势或常见的12种阔叶植物为研究对象,采用单因素方差分析或非参数秩和检验对不同生活型植物或物种间的性状进行差异性分析,以标准化主轴估计(standardized major axis estimation,SMA)对枝叶性状间相关关系进行研究。【结果】不同生活型阔叶植物的枝叶性状有相似的变异趋势,其中枝横截面积和出叶强度变异程度均高于30%,枝干质量变异高于20%,而单叶干质量、总叶面积和单叶面积变异均低于15%;乔木的单叶面积、总叶面积和单叶干质量均显著高于灌木;乔木枝横截面积与单叶面积之间为正异速生长关系,灌木为正等速生长关系;乔木和灌木枝横截面积与总叶面积之间均为正等速生长关系,仅部分物种存在正异速生长关系;乔木和灌木出叶强度与单叶面积、单叶干质量之间为负异速生长关系,仅部分乔木物种呈负等速生长关系。【结论】不同生活型植物间枝叶性状以异速生长关系为主,异速生长更有利于植物生存策略的调节,不同生活型阔叶植物枝叶性状的权衡模式取决于生长方式。
文摘近年来,大语言模型(Large Language Models,LLMs)在情感对话中展现了令人惊叹的能力,并且在实现目标方面表现出较强的能力。然而,现有研究主要集中在通过情感共鸣式的回复提供安慰,而不是通过这些回复实现特定的现实目标。为了填补这一研究空白,提出了一个名为SPEAKSMART的基准,其涵盖5个场景,用于评测LLMs在对话中通过高度共情的回复实现现实目标的能力。随后,引入了一个基于提供者满意度和请求者满意度的二维评测框架。利用SPEAKSMART对多种LLMs进行了评测,并设计了基线方法,以增强其在对话中生成具有说服力的共情回复的能力。实验结果表明,Claude3和LLaMA3-70B在不同场景中的表现最佳,而其他LLMs则有提升空间,这为增强LLMs处理需要高度共情回复以实现目标的现实任务的能力奠定了基础。
基金financially supported by the Science and Technology Innovation Program of Hunan Province,China(No.2023RC3055)the Natural Science Foundation of Hunan Province,China(Nos.2023JJ30671,2020JJ4114)+5 种基金the Natural Science Foundation of Changsha City,China(No.Kq2208264)National Key Project of Research and Development Plan of China(Nos.2021YFC1910505,2021YFC1910504)the Young Core Teacher Foundation of Hunan Province,China(No.150220001)Key Research and Development Program of Guangdong Province,China(No.2020B010186002)the National Natural Science Foundation of China(No.51601229)the Key-Area Research and Development Program of Foshan City,China(No.2230032004640).
文摘The corrosion behavior and microstructure characteristics of metal inert gas(MIG)welded dissimilar joints of the 6005A alloy modified with Sc(designated as 6005A+Sc)and the 5083 alloy were investigated using corrosion tests and microscopy techniques.Results show that the dissimilar joints exhibit strong stress corrosion cracking(SCC)resistance,maintaining substantial strength during slow strain rate tensile tests.Notably,the heat-affected zone(HAZ)and base metal(BM)on the 6005A+Sc side show superior performance in terms of inter-granular corrosion(IGC)and exfoliation corrosion(EXCO)compared to the corresponding zones on the 5083 side.The lower corrosion resistance of the 5083-BM and the 5083-HAZ can be attributed to the presence of numerous Al_(2)Mg_(3)phases and micro-scaled Al_(6)(Mn,Fe)intermetallics,mainly distributed along the rolling direction.Conversely,the enhanced corrosion resistance of the 6005A+Sc-BM and the 6005A+Sc-HAZ can be attributed to the discontinuously distributed grain boundary precipitates(β-Mg_(2)Si),the smaller grain size,and the reduced corrosive current density.
基金supported by the National Natural Science Foundation of China(Grant Nos.U22A20603 and U21A2008)the Science Technology Research Program of the Institute of Mountain Hazards and Environment,Chinese Academy of Sciences(Grant No.IMHE-ZYTS-03).
文摘On September 5,2022,at least 10,855 landslides had been triggered by a magnitude Mw 6.7(Ms 6.8)earthquake on the eastern margin of the Tibetan Plateau.Unfortunately,a detailed analysis of the spatial patterns of landslides in the eastern margin of the Baryan Har block is lacking.The observations show that the highest landslide concentrations are distributed along the seismogenic fault(Moxi fault)and Dadu River valley,coinciding with the effects of the hanging wall and microepicenter.Seismogenic tectonics controlled the regional distribution of new landslides,and the local topography influenced the detailed positions on the slopes.The total landslide mass wasting volume was 223.1×10^(6)m^(3),and the maximum occurred in the Wandong Basin(value of 74×10^(6)m^(3)).Thirty landslide dams were temporarily existing.Although some local collapses occurred at the toe of the Hailuogou glacier,seismic shaking had no obvious influence on the overall stability of the glacier.A post debris flow assessment indicates that some large basins contained much loose material and that some steep small basins had high debris flow susceptibility.On the eastern margin of the Bayan Har block,the landslide-triggering thrust and strike-slip events both follow the distributions of the hanging wall.
文摘This study selected 45 A-share listed companies that have paid dividends for five consecutive years from 2019 to 2024,with an average dividend yield of at least 3%,as the sample.Using a panel data model,the effect of the cash dividend ratio on stock pricing was analyzed.The empirical results indicated a significant positive relationship between the cash dividend ratio and stock price.Furthermore,stocks with high dividend payouts demonstrated greater resilience during macroeconomic downturns,while notable differences were observed across industries.These findings provide a theoretical foundation for investors in making informed decisions and offer practical guidance for listed companies in formulating effective dividend policies.
文摘This study employs leadership contingency theory and resource dependency theory,utilizing financial data from Shanghai and Shenzhen A-share listed companies between 2012 and 2021.Ultimately,data samples from 4,742 companies were selected to empirically examine the impact and moderating role of female executives on corporate digital transformation.Findings reveal that the proportion of female executives positively promotes corporate digital transformation.Further analysis indicates that female executives drive digital transformation by enhancing corporate innovation investment and risk control capabilities.Supported by the heterogeneity analysis,it shows that this effect is more pronounced in high-tech industries,non-state-owned enterprises,and companies in economically developed regions.This study provides a gender-perspective theoretical explanation for the drivers of digital transformation and offers practical insights for optimizing corporate executive teams.
基金supported in part by the Jiangsu Provincial Key Research and Development Program(No.BE2022068-2)in part by the National Natural Science Foundation of China under Grant 62201285+1 种基金in part by Young Elite Scientists Sponsorship Program by CAST under Grant 2022QNRC001in part by the Postgraduate Research&Practice Innovation Program of Jiangsu Province under Grant KYCX23_1012.
文摘Unmanned Aerial Vehicles(UAVs)have been considered to have great potential in supporting reliable and timely data harvesting for Sensor Nodes(SNs)from an Internet of Things(IoT)perspective.However,due to physical limitations,UAVs are unable to further process the harvested data and have to rely on terrestrial servers,thus extra spectrum resource is needed to convey the harvested data.To avoid the cost of extra servers and spectrum resources,in this paper,we consider a UAV-based data harvesting network supported by a Cell-Free massive Multiple-Input-Multiple-Output(CF-mMIMO)system,where a UAV is used to collect and transmit data from SNs to the central processing unit of CF-mMIMO system for processing.In order to avoid using additional spectrum resources,the entire bandwidth is shared among radio access networks and wireless fronthaul links.Moreover,considering the limited capacity of the fronthaul links,the compress-and-forward scheme is adopted.In this work,in order to maximize the ergodically achievable sum rate of SNs,the power allocation of ground access points,the compression of fronthaul links,and also the bandwidth fraction between radio access networks and wireless fronthaul links are jointly optimized.To avoid the high overhead introduced by computing ergodically achievable rates,we introduce an approximate problem,using the large-dimensional random matrix theory,which relies only on statistical channel state information.We solve the nontrivial problem in three steps and propose an algorithm based on weighted minimum mean square error and Dinkelbach’s methods to find solutions.Finally,simulation results show that the proposed algorithm converges quickly and outperforms the baseline algorithms.
基金funded by the European Union’s Horizon 2020 Research and Innovation Program under the Marie Sklodowska-Curie Grant Agreement(Grant No.101026104)by the National Natural Science Foundation of China(Grant No.U20A6004)in part by the State Key Laboratory of Precision Electronics Manufacturing Technology and Equipment(Grant No.JMDZ202314).
文摘In semiconductor precision packaging and other applications involving alignment of automated equipment,the nonlinear motion caused by structural characteristics and friction effects on torque-type rotating motion stages seriously affects output accuracy and stability.To solve this problem,the motion characteristics of a rotating stage and the mechanism by which friction nonlinearity influences accuracy are analyzed in detail.In addition,a compound control strategy based on a kinematic model and the Stribeck friction model is designed.A friction disturbance observer based on output position feedback is improved for simple parameter tuning.Finally,an experimental system is constructed to carry out validation tests,including identification of nonlinear characteristics and performance comparisons.The experimental results show that the linear tracking error of the torque-type rotating stage is less than 1.47µm after adoption of the proposed model-based composite control strategy,and the corresponding rotary angle deviation is less than 0.0153°.The linearity of output motion is increased to 97.59%and the error compensation effect is improved by 51.6%compared with the PID control method.The experimental results confirm that the analysis method adopted here and the proposed compensation strategy can effectively reduce frictional nonlinearity and improve motion accuracy.The proposed method can also be applied to other precision electromechanical systems.
基金Supported by National Natural Science Foundation of China(Grant Nos.52325501,U24B2047).
文摘Current research on robot calibration can be roughly classified into two categories,and both of them have certain inherent limitations.Model-based methods are difficult to model and compensate the pose errors arising from configuration-dependent geometric and non-geometric source errors,whereas the accuracy of data-driven methods depends on a large amount of measurement data.Using a 5-DOF(degrees of freedom)hybrid machining robot as an exemplar,this study presents a model data-driven approach for the calibration of robotic manipulators.An f-DOF realistic robot containing various source errors is visualized as a 6-DOF fictitious robot having error-free parameters,but erroneous actuated/virtual joint motions.The calibration process essentially involves four steps:(1)formulating the linear map relating the pose error twist to the joint motion errors,(2)parameterizing the joint motion errors using second-order polynomials in terms of nominal actuated joint variables,(3)identifying the polynomial coefficients using the weighted least squares plus principal component analysis,and(4)compensating the compensable pose errors by updating the nominal actuated joint variables.The merit of this approach is that it enables compensation of the pose errors caused by configuration-dependent geometric and non-geometric source errors using finite measurement configurations.Experimental studies on a prototype machine illustrate the effectiveness of the proposed approach.
基金supported by the National Natural Science Foundation of China(Nos.21906179 and 22074098)Sichuan Science and Technology Program(No.2021ZYD0047)the Fundamental Research Funds for the Central Universities.
文摘As emerging pollutants,microplastics have recently received considerable attention owing to detection in various organisms and environments.Mass production and widespread use of plastic products increase their potential risks to humans owing to their persistent,mobile,and toxic properties.Numerous methods have been used to identify and quantify the various forms of microplastics,however,unified standards do not exist.In this review,we systematically summarize the sources,migration,transformation,and analytical methods for microplastics in diverse ecosystems,particularly the most recent sampling and identification techniques.Additionally,the environmental effects and health hazards of microplastics on aquatic and terrestrial systems,as well as human beings are discussed.We also present management strategies for reducing microplastics in a broader social and policy context.This review aims to provide an overview of the migration,transformation,sampling,analysis,and environmental effects of microplastics,which addresses knowledge gaps in microplastic pollution and provides proposals for key research gaps.
