This paper mainly deals with two mainstreams in teaching listening comprehension:bottom-up processing approach and top-down processing approach.In the first part of the essay the importance of listening comprehension ...This paper mainly deals with two mainstreams in teaching listening comprehension:bottom-up processing approach and top-down processing approach.In the first part of the essay the importance of listening comprehension in language learning will be demonstrated briefly.Then the author will go on to explore the nature of top-down and bottom-up approaches in teaching listening.Lastly,at the third part of the essay,the author shall try to discuss the possibility of applying these approaches into practice,that is,when and why one of them is more useful.Furthermore in this section,a more integrated view will be introduced.展开更多
Many approaches to teaching reading are available now.However,what these approaches are and how to select one from them is still puzzling many English teachers.The paper analyses three current perspectives on how to t...Many approaches to teaching reading are available now.However,what these approaches are and how to select one from them is still puzzling many English teachers.The paper analyses three current perspectives on how to teach reading and discusses how these affect the way reading is taught and gives an evaluation of these approaches.展开更多
An interactive strategies-based approach to reading teaching involves both bottom-up and top-down skills,which if developed conjointly,will not only improve students'reading comprehension and reading rate but also...An interactive strategies-based approach to reading teaching involves both bottom-up and top-down skills,which if developed conjointly,will not only improve students'reading comprehension and reading rate but also facilitate their ability of writing.展开更多
We propose a forward approach to study the performance of liquidation strategies under sequential model parameter updates.The forward liquidation program consists of pasting forward in time and in a time-consistent fa...We propose a forward approach to study the performance of liquidation strategies under sequential model parameter updates.The forward liquidation program consists of pasting forward in time and in a time-consistent fashion a series of optimal liquidation problems.They are triggered at the parameter shift instances,thus entirely eliminating model error,and last at most till the next parameter update.However,due to the nature of the model dynamics,solutions may cease to exist in finite time,even before the subsequent parameter update.Furthermore,forward liquidation strategies may never lead to full liquidation,even though they maximize the average utility of revenue and always preserve time-consistency.In juxtaposition,the traditional approach delivers full liquidation at the sought horizon but encounters considerable model error,generates value erosion,and is time-inconsistent.展开更多
Flexible electronics offer a multitude of advantages,such as flexibility,lightweight property,portability,and high durability.These unique properties allow for seamless applications to curved and soft surfaces,leading...Flexible electronics offer a multitude of advantages,such as flexibility,lightweight property,portability,and high durability.These unique properties allow for seamless applications to curved and soft surfaces,leading to extensive utilization across a wide range of fields in consumer electronics.These applications,for example,span integrated circuits,solar cells,batteries,wearable devices,bio-implants,soft robotics,and biomimetic applications.Recently,flexible electronic devices have been developed using a variety of materials such as organic,carbon-based,and inorganic semiconducting materials.Silicon(Si)owing to its mature fabrication process,excellent electrical,optical,thermal properties,and cost efficiency,remains a compelling material choice for flexible electronics.Consequently,the research on ultra-thin Si in the context of flexible electronics is studied rigorously nowadays.The thinning of Si is crucially important for flexible electronics as it reduces its bending stiffness and the resultant bending strain,thereby enhancing flexibility while preserving its exceptional properties.This review provides a comprehensive overview of the recent efforts in the fabrication techniques for forming ultra-thin Si using top-down and bottom-up approaches and explores their utilization in flexible electronics and their applications.展开更多
Ecological restoration policies and their implementation are influenced by ecological and socioeconomic drivers.Top-down approach-based spatial planning,emphasizing hierarchical control within government structures,an...Ecological restoration policies and their implementation are influenced by ecological and socioeconomic drivers.Top-down approach-based spatial planning,emphasizing hierarchical control within government structures,and without a comprehensive consideration of social–ecological interactions may result in implementation failure and low efficiency.Although many researchers have indicated the necessity to engage social–ecological interactions between stakeholders in effective planning processes,socioeconomic drivers of ecological restoration on a large scale are difficult to quantify because of data scarcity and knowledge limitations.Here,we established a new ecological restoration planning approach linking a social–ecological system framework to large-scale ecological restoration planning.The new spatial planning approach integrates bottom-up approaches targeting stakeholder interests and provides social considerations for stakeholder behavior analysis.Based on this approach,a meta-analysis is introduced to recognize key socioeconomic and social–ecological factors influencing large-scale ecological restoration implementation,and a stochastic model is constructed to analyze the impact of socioeconomic drivers on the behavior of authorities and participants on a large scale.We used the Yangtze River Basin-based Conversion of Cropland to Forest Program(CCFP),one of the largest payments for ecosystem service programs worldwide,to quantify the socioeconomic impacts of large-scale ecological restoration programs.Current CCFP planning without socioeconomic considerations failed to achieve large-scale program goals and showed low investment efficiency,with 19.71% of the implemented area reconverting to cropland after contract expiry.In contrast,spatial matching between planned and actual restoration increased from 61.55% to 81.86% when socioeconomic drivers were included.In addition,compared to that with the current CCFP implementation,the cost effectiveness of spatial planning with social considerations improved by 46.94%.Thus,spatial optimization planning that integrates both top-down and bottom-up approaches can result in more practical and effective ecological restoration than top-down approaches alone.Our new approach incorporates socioeconomic factors into large-scale ecological restoration planning with high practicality and efficiency.展开更多
Uncertainty widely exists in engineering structures,making it necessary to update the finite element(FE)modeling with uncertainty.An updating approach for the FE model of structural dynamics with interval uncertain pa...Uncertainty widely exists in engineering structures,making it necessary to update the finite element(FE)modeling with uncertainty.An updating approach for the FE model of structural dynamics with interval uncertain parameters is proposed in this work.Firstly,the correlations between the updating parameters and the output qualities of interest are uncorrelated by the principal component analysis(PCA),and the massive samples of major principal components are obtained using the Monte Carlo simulation.Then,the massive samples of updating parameters and output qualities are obtained by reversing transformation in the PCA,and the new samples of updating parameters are re-chosen by combining the massive samples with the experimental intervals of the qualities of interest.Next,the 95%CI of the updating parameters is estimated by the nonparametrie kernel density estimation approach,which are regarded as the intervals of updating parameters.Lastly,the proposed approach is validated in simple rectangular plates and the transport mirror system.The updating results evidently demonstrate the feasibility and reliability of the proposed approach.展开更多
文摘This paper mainly deals with two mainstreams in teaching listening comprehension:bottom-up processing approach and top-down processing approach.In the first part of the essay the importance of listening comprehension in language learning will be demonstrated briefly.Then the author will go on to explore the nature of top-down and bottom-up approaches in teaching listening.Lastly,at the third part of the essay,the author shall try to discuss the possibility of applying these approaches into practice,that is,when and why one of them is more useful.Furthermore in this section,a more integrated view will be introduced.
文摘Many approaches to teaching reading are available now.However,what these approaches are and how to select one from them is still puzzling many English teachers.The paper analyses three current perspectives on how to teach reading and discusses how these affect the way reading is taught and gives an evaluation of these approaches.
文摘An interactive strategies-based approach to reading teaching involves both bottom-up and top-down skills,which if developed conjointly,will not only improve students'reading comprehension and reading rate but also facilitate their ability of writing.
文摘We propose a forward approach to study the performance of liquidation strategies under sequential model parameter updates.The forward liquidation program consists of pasting forward in time and in a time-consistent fashion a series of optimal liquidation problems.They are triggered at the parameter shift instances,thus entirely eliminating model error,and last at most till the next parameter update.However,due to the nature of the model dynamics,solutions may cease to exist in finite time,even before the subsequent parameter update.Furthermore,forward liquidation strategies may never lead to full liquidation,even though they maximize the average utility of revenue and always preserve time-consistency.In juxtaposition,the traditional approach delivers full liquidation at the sought horizon but encounters considerable model error,generates value erosion,and is time-inconsistent.
基金supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. RS-2024-00353768)the Yonsei Fellowship, funded by Lee Youn Jae. This study was funded by the KIST Institutional Program Project No. 2E31603-22-140 (K J Y). S M W acknowledges the support by National Research Foundation of Korea (NRF) grant funded by the Korea government (Grant Nos. NRF-2021R1C1C1009410, NRF2022R1A4A3032913 and RS-2024-00411904)
文摘Flexible electronics offer a multitude of advantages,such as flexibility,lightweight property,portability,and high durability.These unique properties allow for seamless applications to curved and soft surfaces,leading to extensive utilization across a wide range of fields in consumer electronics.These applications,for example,span integrated circuits,solar cells,batteries,wearable devices,bio-implants,soft robotics,and biomimetic applications.Recently,flexible electronic devices have been developed using a variety of materials such as organic,carbon-based,and inorganic semiconducting materials.Silicon(Si)owing to its mature fabrication process,excellent electrical,optical,thermal properties,and cost efficiency,remains a compelling material choice for flexible electronics.Consequently,the research on ultra-thin Si in the context of flexible electronics is studied rigorously nowadays.The thinning of Si is crucially important for flexible electronics as it reduces its bending stiffness and the resultant bending strain,thereby enhancing flexibility while preserving its exceptional properties.This review provides a comprehensive overview of the recent efforts in the fabrication techniques for forming ultra-thin Si using top-down and bottom-up approaches and explores their utilization in flexible electronics and their applications.
基金the National Natural Science Foundation of China(41925005 and 72022014)the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(2019QZKK0307)。
文摘Ecological restoration policies and their implementation are influenced by ecological and socioeconomic drivers.Top-down approach-based spatial planning,emphasizing hierarchical control within government structures,and without a comprehensive consideration of social–ecological interactions may result in implementation failure and low efficiency.Although many researchers have indicated the necessity to engage social–ecological interactions between stakeholders in effective planning processes,socioeconomic drivers of ecological restoration on a large scale are difficult to quantify because of data scarcity and knowledge limitations.Here,we established a new ecological restoration planning approach linking a social–ecological system framework to large-scale ecological restoration planning.The new spatial planning approach integrates bottom-up approaches targeting stakeholder interests and provides social considerations for stakeholder behavior analysis.Based on this approach,a meta-analysis is introduced to recognize key socioeconomic and social–ecological factors influencing large-scale ecological restoration implementation,and a stochastic model is constructed to analyze the impact of socioeconomic drivers on the behavior of authorities and participants on a large scale.We used the Yangtze River Basin-based Conversion of Cropland to Forest Program(CCFP),one of the largest payments for ecosystem service programs worldwide,to quantify the socioeconomic impacts of large-scale ecological restoration programs.Current CCFP planning without socioeconomic considerations failed to achieve large-scale program goals and showed low investment efficiency,with 19.71% of the implemented area reconverting to cropland after contract expiry.In contrast,spatial matching between planned and actual restoration increased from 61.55% to 81.86% when socioeconomic drivers were included.In addition,compared to that with the current CCFP implementation,the cost effectiveness of spatial planning with social considerations improved by 46.94%.Thus,spatial optimization planning that integrates both top-down and bottom-up approaches can result in more practical and effective ecological restoration than top-down approaches alone.Our new approach incorporates socioeconomic factors into large-scale ecological restoration planning with high practicality and efficiency.
基金the Science Challenge Project(Grant No.TZ2018007)the National Key Research and Development Program of China(Grant No.2016YFB0201005)the National Natural Science Foundation of China(Grant No.11472256).
文摘Uncertainty widely exists in engineering structures,making it necessary to update the finite element(FE)modeling with uncertainty.An updating approach for the FE model of structural dynamics with interval uncertain parameters is proposed in this work.Firstly,the correlations between the updating parameters and the output qualities of interest are uncorrelated by the principal component analysis(PCA),and the massive samples of major principal components are obtained using the Monte Carlo simulation.Then,the massive samples of updating parameters and output qualities are obtained by reversing transformation in the PCA,and the new samples of updating parameters are re-chosen by combining the massive samples with the experimental intervals of the qualities of interest.Next,the 95%CI of the updating parameters is estimated by the nonparametrie kernel density estimation approach,which are regarded as the intervals of updating parameters.Lastly,the proposed approach is validated in simple rectangular plates and the transport mirror system.The updating results evidently demonstrate the feasibility and reliability of the proposed approach.
基金supported by the National Natural Science Foundation of China(12071452,72091212,11601500)USTC Research Funds of the Double First-Class Initiative(YD2040002013).
