How has the informality of urban slums exposed a gap in policy formulation and research questions in the wake of the coronavirus disease 2019(COVID-19)pandemic?This paper seeks to identify the appropriate questions an...How has the informality of urban slums exposed a gap in policy formulation and research questions in the wake of the coronavirus disease 2019(COVID-19)pandemic?This paper seeks to identify the appropriate questions and policy frame that would assist future researchers and policymakers on the subject of pandemics in densely populated urban settlements.The authors argue that the nexus between asking the appropriate questions and developing appropriate policy response measures during a pandemic can significantly impact the outcome of the response.The paper examines how the government of Kenya's response to the COVID-19 pandemic reveals a deep-rooted socio-economic and cultural inequality when"blanket"policies are adopted without taking into consideration the tnique dynamics characterizing the society.The findings show that the effectiveness of implementing COVID-19 containment policies such as lockdowns,the cession of movement,working from home,distance learning,and social distancing are affected by other factors such as the nature of jobs,one's income levels,where someone lives,cultural beliefs,access to water,sanitation,intemet,and medical facilities.This means that a significant number of people within the society experience a double tragedy from the pandemic and impact of government response measures.Yet most of the existing literature has focused on the causes,spread,and impact of the pandemic on health institutions,economies,and public health with little emphasis on the impact on policy measures especially on the vulnerable segments of the society.This paper,therefore,looks at the question of how the various public health intervention strategies disrupt or construct the livelihood of the already complex informal settlement.It provides policymakers and researchers with a number of questions that can frame policy and research during a pandemic with important consideration to urban informality.展开更多
Related to the academic topic on innovation and development of information-communication industries,a dualist distinction between formal and informal economy has drawn a lot of research interests in the academy circle...Related to the academic topic on innovation and development of information-communication industries,a dualist distinction between formal and informal economy has drawn a lot of research interests in the academy circle in recent years.In this essay,we discussed the background of Shenzhen’s leapfrog development as a Chinese economic special zone thanks to several policy advantages and the endeavor of itself as a principal part in the framework of China’s market economy reform.Despite the problem of informal economy for citizen’s living,we mainly focused on the positive effect of Shenzhen’s informal economy as flexibility of capital-labor effective coordination.Based on the analysis of the evolution of Shenzhen’s city construction and industrial development,and the analysis on the four development stages that Shenzhen had witnessed,we expect more practical and theoretical summary of its experience for all the developing countries.展开更多
The study on informality has experienced a shift from describing the spatial characteristics toward exploring the connotation of urban governance in recent years. This paper takes urban villages in Shenzhen, a typical...The study on informality has experienced a shift from describing the spatial characteristics toward exploring the connotation of urban governance in recent years. This paper takes urban villages in Shenzhen, a typical informal settlement in China, as cases to analyze the two urban village governance modes of redevelopment and in situ upgrading and reveals the dynamics of the governance mode transformation. Through the lens of informality, this study focuses on the interaction among the government, the market, and former property owners on tenure legalization. The study finds that first of all, informality is the core of the transformation of urban village governance in Shenzhen. By strategically making use of informality, the government adopted different modes of urban village governance to fulfill the demands of urban development at different phases. Second, in the process of formalizing informal settlements through redevelopment, although the institutional framework is relatively complete, the boundary between informality and formality still changes continuously in property titling. While in the new governance mode of in situ upgrading in recent years, the government creates "special areas" in informal settlements via approving their de facto tenure security, so as to attract market force to upgrade physical environment and social management. Through revealing the mechanism in the blurred area between informality and formality, this paper responds to the dualistic argument on the informality theory, deepens the idea of taking informality as a flexible urban governance strategy in developing countries, and provides new thoughts for governance of informal settlements in China and other developing countries.展开更多
Experimental therapies targeting immune and stromal cells,such as mast cells,cancer-associated fibroblasts,dendritic cells,and tumor endothelial cells,in the treatment of gastrointestinal solid tumors pose new and com...Experimental therapies targeting immune and stromal cells,such as mast cells,cancer-associated fibroblasts,dendritic cells,and tumor endothelial cells,in the treatment of gastrointestinal solid tumors pose new and complex surgical and medico-legal challenges.These innovative treatments require that informed consent not be limited to simple acceptance of the medical procedure,but instead reflect a true relational and cognitive process grounded in understanding,free choice,and the ability to revoke consent at any time.In particular,it is essential that the patient understands the experimental nature of the therapy,its development stage,potential benefits and risks,as well as the implications for their health and personal dignity.In the case of stromal cell-based treatments,which may exert complex immunomodulatory effects or activate angiogenic pathways that are not yet fully understood,patients must be made fully aware that they are participating in a non-standardized therapy whose outcomes,whether beneficial or harmful,cannot yet be predicted with certainty.This requires particularly careful medical communication,using simple yet scientifically accurate explanations delivered in appropriate language,along with a final verification of the patient’s actual understanding.展开更多
People read many things online these days.It's an easy way to get a lot of information fast.They look at news,see posts and watch videos.But how much of the information is true?Some things online are fake.So it...People read many things online these days.It's an easy way to get a lot of information fast.They look at news,see posts and watch videos.But how much of the information is true?Some things online are fake.So it's important to check the facts before you believe or share anything.You can ask people or look at other sources first.Check newspapers or official websites.Always think carefully before you believe something online.展开更多
1 General information Journal of Geographical Sciences is an international academic journal that publishes papers of the highest quality in physical geography, natural resources, environmental sciences, geographic inf...1 General information Journal of Geographical Sciences is an international academic journal that publishes papers of the highest quality in physical geography, natural resources, environmental sciences, geographic information sciences, remote sensing and cartography. Manuscripts come from different parts of the world.展开更多
Human activities have significantly impacted the land surface temperature(LST),endangering human health;however,the relationship between these two factors has not been adequately quantified.This study comprehensively ...Human activities have significantly impacted the land surface temperature(LST),endangering human health;however,the relationship between these two factors has not been adequately quantified.This study comprehensively constructs a Human Activity Intensity(HAI)index and employs the Maximal Information Coefficient,four-quadrant model,and XGBoostSHAP model to investigate the spatiotemporal relationship and influencing factors of HAI-LST in the Yellow River Basin(YRB)from 2000 to 2020.The results indicated that from 2000 to 2020,as HAI and LST increased,the static HAI-LST relationship in the YRB showed a positive correlation that continued to strengthen.This dynamic relationship exhibited conflicting development,with the proportion of coordinated to conflicting regions shifting from 1:4 to 1:2,indicating a reduction in conflict intensity.Notably,only the degree of conflict in the source area decreased significantly,whereas it intensified in the upper and lower reaches.The key factors influencing the HAI-LST relationship include fractional vegetation cover,slope,precipitation,and evapotranspiration,along with region-specific factors such as PM_(2.5),biodiversity,and elevation.Based on these findings,region-specific ecological management strategies have been proposed to mitigate conflict-prone areas and alleviate thermal stress,thereby providing important guidance for promoting harmonious development between humans and nature.展开更多
Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instabili...Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instability,occur frequently in both experimental and operational data.This infrequency causes events to be overlooked by existing prediction models,which lack the precision to accurately predict inclination attitudes in amphibious vehicles.To address this gap in predicting attitudes near extreme inclination points,this study introduces a novel loss function,termed generalized extreme value loss.Subsequently,a deep learning model for improved waterborne attitude prediction,termed iInformer,was developed using a Transformer-based approach.During the embedding phase,a text prototype is created based on the vehicle’s operation log data is constructed to help the model better understand the vehicle’s operating environment.Data segmentation techniques are used to highlight local data variation features.Furthermore,to mitigate issues related to poor convergence and slow training speeds caused by the extreme value loss function,a teacher forcing mechanism is integrated into the model,enhancing its convergence capabilities.Experimental results validate the effectiveness of the proposed method,demonstrating its ability to handle data imbalance challenges.Specifically,the model achieves over a 60%improvement in root mean square error under extreme value conditions,with significant improvements observed across additional metrics.展开更多
Quantum control allows a wide range of quantum operations employed in molecular physics,nuclear magnetic resonance and quantum information processing.Thanks to the existing microelectronics industry,semiconducting qub...Quantum control allows a wide range of quantum operations employed in molecular physics,nuclear magnetic resonance and quantum information processing.Thanks to the existing microelectronics industry,semiconducting qubits,where quantum information is encoded in spin or charge degree freedom of electrons or nuclei in semiconductor quantum dots,constitute a highly competitive candidate for scalable solid-state quantum technologies.In quantum information processing,advanced control techniques are needed to realize quantum manipulations with both high precision and noise resilience.In this review,we first introduce the basics of various widely-used control methods,including resonant excitation,adabatic passage,shortcuts to adiabaticity,composite pulses,and quantum optimal control.Then we review the practical aspects in applying these methods to realize accurate and robust quantum gates for single semiconductor qubits,such as Loss–DiVincenzo spin qubit,spinglet-triplet qubit,exchange-only qubit and charge qubit.展开更多
Recommending personalized travel routes from sparse,implicit feedback poses a significant challenge,as conventional systems often struggle with information overload and fail to capture the complex,sequential nature of...Recommending personalized travel routes from sparse,implicit feedback poses a significant challenge,as conventional systems often struggle with information overload and fail to capture the complex,sequential nature of user preferences.To address this,we propose a Conditional Generative Adversarial Network(CGAN)that generates diverse and highly relevant itineraries.Our approach begins by constructing a conditional vector that encapsulates a user’s profile.This vector uniquely fuses embeddings from a Heterogeneous Information Network(HIN)to model complex user-place-route relationships,a Recurrent Neural Network(RNN)to capture sequential path dynamics,and Neural Collaborative Filtering(NCF)to incorporate collaborative signals from the wider user base.This comprehensive condition,further enhanced with features representing user interaction confidence and uncertainty,steers a CGAN stabilized by spectral normalization to generate high-fidelity latent route representations,effectively mitigating the data sparsity problem.Recommendations are then formulated using an Anchor-and-Expand algorithm,which selects relevant starting Points of Interest(POI)based on user history,then expands routes through latent similarity matching and geographic coherence optimization,culminating in Traveling Salesman Problem(TSP)-based route optimization for practical travel distances.Experiments on a real-world check-in dataset validate our model’s unique generative capability,achieving F1 scores ranging from 0.163 to 0.305,and near-zero pairs−F1 scores between 0.002 and 0.022.These results confirm the model’s success in generating novel travel routes by recommending new locations and sequences rather than replicating users’past itineraries.This work provides a robust solution for personalized travel planning,capable of generating novel and compelling routes for both new and existing users by learning from collective travel intelligence.展开更多
With the growing advancement of wireless communication technologies,WiFi-based human sensing has gained increasing attention as a non-intrusive and device-free solution.Among the available signal types,Channel State I...With the growing advancement of wireless communication technologies,WiFi-based human sensing has gained increasing attention as a non-intrusive and device-free solution.Among the available signal types,Channel State Information(CSI)offers fine-grained temporal,frequency,and spatial insights into multipath propagation,making it a crucial data source for human-centric sensing.Recently,the integration of deep learning has significantly improved the robustness and automation of feature extraction from CSI in complex environments.This paper provides a comprehensive review of deep learning-enhanced human sensing based on CSI.We first outline mainstream CSI acquisition tools and their hardware specifications,then provide a detailed discussion of preprocessing methods such as denoising,time–frequency transformation,data segmentation,and augmentation.Subsequently,we categorize deep learning approaches according to sensing tasks—namely detection,localization,and recognition—and highlight representative models across application scenarios.Finally,we examine key challenges including domain generalization,multi-user interference,and limited data availability,and we propose future research directions involving lightweight model deployment,multimodal data fusion,and semantic-level sensing.展开更多
Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to thei...Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to their small gyromagnetic ratios.A promising approach to achieving high nuclear spin polarization is transferring the polarization of electrons to nuclear spins.The nitrogen-vacancy(NV)center in diamond has emerged as a highly effective medium for this purpose,and various hyperpolarization protocols have been developed.Among these,the pulsed polarization(PulsePol)method has been extensively studied due to its robustness against static energy shifts of the electron spin.In this work,we present a novel polarization protocol and uncover a family of magic sequences for hyperpolarizing nuclear spins,with PulsePol emerging as a special case of our general approach.Notably,we demonstrate that some of these magic sequences exhibit significantly greater robustness compared to the PulsePol protocol in the presence of finite half𝜋pulse duration of the protocol,Rabi and detuning errors.This enhanced robustness positions our protocol as a more suitable candidate for hyper-polarizing nuclear spins species with large gyromagnetic ratios and also ensures better compatibility with high-efficiency readout techniques at high magnetic fields.Additionally,the generality of our protocol allows for its direct application to other solid-state quantum systems beyond the NV center.展开更多
The development of quantum materials for single-photon emission is crucial for the advancement of quantum information technology.Although significant advancements have been witnessed in recent years for single-photon ...The development of quantum materials for single-photon emission is crucial for the advancement of quantum information technology.Although significant advancements have been witnessed in recent years for single-photon sources in the near-infrared band(λ∼700–1000 nm),several challenges have yet to be addressed for ideal single-photon emission at the telecommunication band.In this study,we present a droplet-epitaxy strategy for O-band to C-band single-photon source-based semiconductor quantum dots(QDs)using metal-organic vaporphase epitaxy(MOVPE).By investigating the growth conditions of the epitaxial process,we have successfully synthesized InAs/InP QDs with narrow emission lines spanning a broad spectral range of λ∼1200–1600 nm.The morphological and optical properties of the samples were characterized using atomic force microscopy and microphotoluminescence spectroscopy.The recorded single-photon purity of a plain QD structure reaches g^((2))(0)=0.16,with a radiative recombination lifetime as short as 1.5 ns.This work provides a crucial platform for future research on integrated microcavity enhancement techniques and coupled QDs with other quantum photonics in the telecom bands,offering significant prospects for quantum network applications.展开更多
为了保证运维阶段桥梁结构安全,提升桥梁运维工作的效率,开展公路混凝土梁式桥运维阶段建筑信息模型(building information modeling,BIM)技术应用研究。在对公路桥梁现行编码体系进行扩展的基础上,提出1种参数化快速建模方法,以快速完...为了保证运维阶段桥梁结构安全,提升桥梁运维工作的效率,开展公路混凝土梁式桥运维阶段建筑信息模型(building information modeling,BIM)技术应用研究。在对公路桥梁现行编码体系进行扩展的基础上,提出1种参数化快速建模方法,以快速完成桥梁构件族的创建与整体模型的集成。借助Autodesk Revit软件应用程序编程接口(application programming interface,API),采用C#语言,开发公路混凝土梁式桥智慧运维状态评估系统,以实际工程应用进行验证分析。研究结果表明:全面统一的桥梁信息编码体系,能够提高桥梁信息统计与检索效率;提出的快速建模方法能够显著减少建模工作量,建模时间较传统建模方法可减少60%,并保证模型的准确性与规范性;运维状态评估系统能够实现养护数据的充分利用与桥梁评定工作的自动化,通过对桥梁运维信息的有效组织,实现服役性能的长期追踪,从而确保运营期桥梁结构状态安全稳定。研究结果可为公路混凝土梁式桥运维管理提供技术支撑,提升桥梁运维的数字化水平。展开更多
文摘How has the informality of urban slums exposed a gap in policy formulation and research questions in the wake of the coronavirus disease 2019(COVID-19)pandemic?This paper seeks to identify the appropriate questions and policy frame that would assist future researchers and policymakers on the subject of pandemics in densely populated urban settlements.The authors argue that the nexus between asking the appropriate questions and developing appropriate policy response measures during a pandemic can significantly impact the outcome of the response.The paper examines how the government of Kenya's response to the COVID-19 pandemic reveals a deep-rooted socio-economic and cultural inequality when"blanket"policies are adopted without taking into consideration the tnique dynamics characterizing the society.The findings show that the effectiveness of implementing COVID-19 containment policies such as lockdowns,the cession of movement,working from home,distance learning,and social distancing are affected by other factors such as the nature of jobs,one's income levels,where someone lives,cultural beliefs,access to water,sanitation,intemet,and medical facilities.This means that a significant number of people within the society experience a double tragedy from the pandemic and impact of government response measures.Yet most of the existing literature has focused on the causes,spread,and impact of the pandemic on health institutions,economies,and public health with little emphasis on the impact on policy measures especially on the vulnerable segments of the society.This paper,therefore,looks at the question of how the various public health intervention strategies disrupt or construct the livelihood of the already complex informal settlement.It provides policymakers and researchers with a number of questions that can frame policy and research during a pandemic with important consideration to urban informality.
文摘Related to the academic topic on innovation and development of information-communication industries,a dualist distinction between formal and informal economy has drawn a lot of research interests in the academy circle in recent years.In this essay,we discussed the background of Shenzhen’s leapfrog development as a Chinese economic special zone thanks to several policy advantages and the endeavor of itself as a principal part in the framework of China’s market economy reform.Despite the problem of informal economy for citizen’s living,we mainly focused on the positive effect of Shenzhen’s informal economy as flexibility of capital-labor effective coordination.Based on the analysis of the evolution of Shenzhen’s city construction and industrial development,and the analysis on the four development stages that Shenzhen had witnessed,we expect more practical and theoretical summary of its experience for all the developing countries.
基金funded by the National Natural Science Fund of China(No.51578304)PhD Dissertation Scholarship of Urban Development and Land Policy Research Center,Peking University–Lincoln Institute of Land Policy(No.DS03-20180901-GXY)+3 种基金the National Social Science Fund of China(No.16CRK020)the Humanity and Social Science Research Youth Foundation of China’s Ministry of Education(No.15YJCZH016)the Social Science Foundation of Beijing,China(No.15SHC043)the Horizon 2020 Research&Innovation Program(No.770141)
文摘The study on informality has experienced a shift from describing the spatial characteristics toward exploring the connotation of urban governance in recent years. This paper takes urban villages in Shenzhen, a typical informal settlement in China, as cases to analyze the two urban village governance modes of redevelopment and in situ upgrading and reveals the dynamics of the governance mode transformation. Through the lens of informality, this study focuses on the interaction among the government, the market, and former property owners on tenure legalization. The study finds that first of all, informality is the core of the transformation of urban village governance in Shenzhen. By strategically making use of informality, the government adopted different modes of urban village governance to fulfill the demands of urban development at different phases. Second, in the process of formalizing informal settlements through redevelopment, although the institutional framework is relatively complete, the boundary between informality and formality still changes continuously in property titling. While in the new governance mode of in situ upgrading in recent years, the government creates "special areas" in informal settlements via approving their de facto tenure security, so as to attract market force to upgrade physical environment and social management. Through revealing the mechanism in the blurred area between informality and formality, this paper responds to the dualistic argument on the informality theory, deepens the idea of taking informality as a flexible urban governance strategy in developing countries, and provides new thoughts for governance of informal settlements in China and other developing countries.
文摘Experimental therapies targeting immune and stromal cells,such as mast cells,cancer-associated fibroblasts,dendritic cells,and tumor endothelial cells,in the treatment of gastrointestinal solid tumors pose new and complex surgical and medico-legal challenges.These innovative treatments require that informed consent not be limited to simple acceptance of the medical procedure,but instead reflect a true relational and cognitive process grounded in understanding,free choice,and the ability to revoke consent at any time.In particular,it is essential that the patient understands the experimental nature of the therapy,its development stage,potential benefits and risks,as well as the implications for their health and personal dignity.In the case of stromal cell-based treatments,which may exert complex immunomodulatory effects or activate angiogenic pathways that are not yet fully understood,patients must be made fully aware that they are participating in a non-standardized therapy whose outcomes,whether beneficial or harmful,cannot yet be predicted with certainty.This requires particularly careful medical communication,using simple yet scientifically accurate explanations delivered in appropriate language,along with a final verification of the patient’s actual understanding.
文摘People read many things online these days.It's an easy way to get a lot of information fast.They look at news,see posts and watch videos.But how much of the information is true?Some things online are fake.So it's important to check the facts before you believe or share anything.You can ask people or look at other sources first.Check newspapers or official websites.Always think carefully before you believe something online.
文摘1 General information Journal of Geographical Sciences is an international academic journal that publishes papers of the highest quality in physical geography, natural resources, environmental sciences, geographic information sciences, remote sensing and cartography. Manuscripts come from different parts of the world.
基金Shanxi Province Graduate Research Practice Innovation Project,No.2023KY465Project on the Reform of Graduate Education and Teaching in Shanxi Province,No.2021YJJG146+1 种基金Research Project of Shanxi Provincial Cultural Relics Bureau,No.22-8-14-1400-119National Key R&D Program of China,No.2021YFB3901300。
文摘Human activities have significantly impacted the land surface temperature(LST),endangering human health;however,the relationship between these two factors has not been adequately quantified.This study comprehensively constructs a Human Activity Intensity(HAI)index and employs the Maximal Information Coefficient,four-quadrant model,and XGBoostSHAP model to investigate the spatiotemporal relationship and influencing factors of HAI-LST in the Yellow River Basin(YRB)from 2000 to 2020.The results indicated that from 2000 to 2020,as HAI and LST increased,the static HAI-LST relationship in the YRB showed a positive correlation that continued to strengthen.This dynamic relationship exhibited conflicting development,with the proportion of coordinated to conflicting regions shifting from 1:4 to 1:2,indicating a reduction in conflict intensity.Notably,only the degree of conflict in the source area decreased significantly,whereas it intensified in the upper and lower reaches.The key factors influencing the HAI-LST relationship include fractional vegetation cover,slope,precipitation,and evapotranspiration,along with region-specific factors such as PM_(2.5),biodiversity,and elevation.Based on these findings,region-specific ecological management strategies have been proposed to mitigate conflict-prone areas and alleviate thermal stress,thereby providing important guidance for promoting harmonious development between humans and nature.
基金Supported by the National Defense Basic Scientific Research Program of China.
文摘Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instability,occur frequently in both experimental and operational data.This infrequency causes events to be overlooked by existing prediction models,which lack the precision to accurately predict inclination attitudes in amphibious vehicles.To address this gap in predicting attitudes near extreme inclination points,this study introduces a novel loss function,termed generalized extreme value loss.Subsequently,a deep learning model for improved waterborne attitude prediction,termed iInformer,was developed using a Transformer-based approach.During the embedding phase,a text prototype is created based on the vehicle’s operation log data is constructed to help the model better understand the vehicle’s operating environment.Data segmentation techniques are used to highlight local data variation features.Furthermore,to mitigate issues related to poor convergence and slow training speeds caused by the extreme value loss function,a teacher forcing mechanism is integrated into the model,enhancing its convergence capabilities.Experimental results validate the effectiveness of the proposed method,demonstrating its ability to handle data imbalance challenges.Specifically,the model achieves over a 60%improvement in root mean square error under extreme value conditions,with significant improvements observed across additional metrics.
基金support by the National Natural Science Foundation of China(Nos.12174379,E31Q02BG)the Chinese Academy of Sciences(Nos.E0SEBB11,E27RBB11)+1 种基金the Innovation Program for Quantum Science and Technology(No.2021ZD0302300)Chinese Academy of Sciences Project for Young Scientists in Basic Research(No.YSBR-090)。
文摘Quantum control allows a wide range of quantum operations employed in molecular physics,nuclear magnetic resonance and quantum information processing.Thanks to the existing microelectronics industry,semiconducting qubits,where quantum information is encoded in spin or charge degree freedom of electrons or nuclei in semiconductor quantum dots,constitute a highly competitive candidate for scalable solid-state quantum technologies.In quantum information processing,advanced control techniques are needed to realize quantum manipulations with both high precision and noise resilience.In this review,we first introduce the basics of various widely-used control methods,including resonant excitation,adabatic passage,shortcuts to adiabaticity,composite pulses,and quantum optimal control.Then we review the practical aspects in applying these methods to realize accurate and robust quantum gates for single semiconductor qubits,such as Loss–DiVincenzo spin qubit,spinglet-triplet qubit,exchange-only qubit and charge qubit.
基金supported by the Chung-Ang University Research Grants in 2023.Alsothe work is supported by the ELLIIT Excellence Center at Linköping–Lund in Information Technology in Sweden.
文摘Recommending personalized travel routes from sparse,implicit feedback poses a significant challenge,as conventional systems often struggle with information overload and fail to capture the complex,sequential nature of user preferences.To address this,we propose a Conditional Generative Adversarial Network(CGAN)that generates diverse and highly relevant itineraries.Our approach begins by constructing a conditional vector that encapsulates a user’s profile.This vector uniquely fuses embeddings from a Heterogeneous Information Network(HIN)to model complex user-place-route relationships,a Recurrent Neural Network(RNN)to capture sequential path dynamics,and Neural Collaborative Filtering(NCF)to incorporate collaborative signals from the wider user base.This comprehensive condition,further enhanced with features representing user interaction confidence and uncertainty,steers a CGAN stabilized by spectral normalization to generate high-fidelity latent route representations,effectively mitigating the data sparsity problem.Recommendations are then formulated using an Anchor-and-Expand algorithm,which selects relevant starting Points of Interest(POI)based on user history,then expands routes through latent similarity matching and geographic coherence optimization,culminating in Traveling Salesman Problem(TSP)-based route optimization for practical travel distances.Experiments on a real-world check-in dataset validate our model’s unique generative capability,achieving F1 scores ranging from 0.163 to 0.305,and near-zero pairs−F1 scores between 0.002 and 0.022.These results confirm the model’s success in generating novel travel routes by recommending new locations and sequences rather than replicating users’past itineraries.This work provides a robust solution for personalized travel planning,capable of generating novel and compelling routes for both new and existing users by learning from collective travel intelligence.
基金supported by National Natural Science Foundation of China(NSFC)under grant U23A20310.
文摘With the growing advancement of wireless communication technologies,WiFi-based human sensing has gained increasing attention as a non-intrusive and device-free solution.Among the available signal types,Channel State Information(CSI)offers fine-grained temporal,frequency,and spatial insights into multipath propagation,making it a crucial data source for human-centric sensing.Recently,the integration of deep learning has significantly improved the robustness and automation of feature extraction from CSI in complex environments.This paper provides a comprehensive review of deep learning-enhanced human sensing based on CSI.We first outline mainstream CSI acquisition tools and their hardware specifications,then provide a detailed discussion of preprocessing methods such as denoising,time–frequency transformation,data segmentation,and augmentation.Subsequently,we categorize deep learning approaches according to sensing tasks—namely detection,localization,and recognition—and highlight representative models across application scenarios.Finally,we examine key challenges including domain generalization,multi-user interference,and limited data availability,and we propose future research directions involving lightweight model deployment,multimodal data fusion,and semantic-level sensing.
基金supported by the National Natural Science Foundation of China (Grant Nos.12475012,62461160263 for P.W.,and 62276171 for H.L.)Quantum Science and Technology-National Science and Technology Major Project of China (Project No.2023ZD0300600 for P.W.)+3 种基金Guangdong Provincial Quantum Science Strategic Initiative (Grant Nos.GDZX240-3009 and GDZX2303005 for P.W.)Guangdong Basic and Applied Basic Research Foundation (Grant No.2024-A1515011938 for H.L.)Shenzhen Fundamental ResearchGeneral Project (Grant No.JCYJ20240813141503005 for H.L.)the Talents Introduction Foundation of Beijing Normal University (Grant No.310432106 for P.W.)。
文摘Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to their small gyromagnetic ratios.A promising approach to achieving high nuclear spin polarization is transferring the polarization of electrons to nuclear spins.The nitrogen-vacancy(NV)center in diamond has emerged as a highly effective medium for this purpose,and various hyperpolarization protocols have been developed.Among these,the pulsed polarization(PulsePol)method has been extensively studied due to its robustness against static energy shifts of the electron spin.In this work,we present a novel polarization protocol and uncover a family of magic sequences for hyperpolarizing nuclear spins,with PulsePol emerging as a special case of our general approach.Notably,we demonstrate that some of these magic sequences exhibit significantly greater robustness compared to the PulsePol protocol in the presence of finite half𝜋pulse duration of the protocol,Rabi and detuning errors.This enhanced robustness positions our protocol as a more suitable candidate for hyper-polarizing nuclear spins species with large gyromagnetic ratios and also ensures better compatibility with high-efficiency readout techniques at high magnetic fields.Additionally,the generality of our protocol allows for its direct application to other solid-state quantum systems beyond the NV center.
基金supported by the National Natural Science Foundation of China (Grant Nos.12494604,12393834,12393831,62274014,6223501662335015)the National Key R&D Program of China (Grant No.2024YFA1208900)。
文摘The development of quantum materials for single-photon emission is crucial for the advancement of quantum information technology.Although significant advancements have been witnessed in recent years for single-photon sources in the near-infrared band(λ∼700–1000 nm),several challenges have yet to be addressed for ideal single-photon emission at the telecommunication band.In this study,we present a droplet-epitaxy strategy for O-band to C-band single-photon source-based semiconductor quantum dots(QDs)using metal-organic vaporphase epitaxy(MOVPE).By investigating the growth conditions of the epitaxial process,we have successfully synthesized InAs/InP QDs with narrow emission lines spanning a broad spectral range of λ∼1200–1600 nm.The morphological and optical properties of the samples were characterized using atomic force microscopy and microphotoluminescence spectroscopy.The recorded single-photon purity of a plain QD structure reaches g^((2))(0)=0.16,with a radiative recombination lifetime as short as 1.5 ns.This work provides a crucial platform for future research on integrated microcavity enhancement techniques and coupled QDs with other quantum photonics in the telecom bands,offering significant prospects for quantum network applications.
