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Bibliometrics-based Research Hotspots and Development Trends in Eco-hydrology of Dammed Rivers
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作者 CHEN Yingyi FENG Mingming +2 位作者 SHI Guoqiang JIANG Mengyu JIANG Ming 《Chinese Geographical Science》 SCIE CSCD 2023年第6期1153-1164,共12页
Water conservation initiatives satisfy the demand for water supply,electricity generation,irrigation,and flood control.While helping humanity,they have also altered the ecosystem of natural rivers,impacted river ecolo... Water conservation initiatives satisfy the demand for water supply,electricity generation,irrigation,and flood control.While helping humanity,they have also altered the ecosystem of natural rivers,impacted river ecology,disrupted river continuity,and jeopardized the existence of aquatic creatures in rivers.Studying the impacts of dam construction on rivers can enhance our knowledge of river ecological and environmental concerns and help sustain the health of river ecosystems,thereby realizing the harmony between humans and water in both theoretical and practical aspects.This study used bibliometrics and constructed an author-keyword 2-mode matrix network using Co-Occurrence software to identify the hotspots and research trend in eco-hydrology of dammed rivers.We identified‘FLOW’‘SEDIMENT’‘QUALITY’and‘MODEL’as the research hotspots in the ecological impact of dammed rivers,and combined the related literatures,we highlight the research progress in the four directions.Then the research shortcomings and prospect were discussed,including strengthening the monitoring and analysis of critical ecological variables,enhancing the hydrological monitoring density for small rivers,strengthening the research of relationship between eutrophication and zooplankton,establishing multiscale approaches,and combining multi-sources information technologies to improve parameter accuracy in the model research. 展开更多
关键词 dammed river ECO-HYDROLOGY BIBLIOMETRICS ecological impact Co-Occurrence software
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Visible to near-infrared photodetector based on organic semiconductor single crystal
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作者 LI Xiang HU Jin-Han +7 位作者 ZHONG Zhi-Peng CHEN Yu-Zhong WANG Zhi-Qiang SONG Miao-Miao WANG Yang ZHANG Lei LI Jian-Feng HUANG Hai 《红外与毫米波学报》 北大核心 2025年第1期46-51,共6页
Organic semiconductor materials have shown unique advantages in the development of optoelectronic devices due to their ease of preparation,low cost,lightweight,and flexibility.In this work,we explored the application ... Organic semiconductor materials have shown unique advantages in the development of optoelectronic devices due to their ease of preparation,low cost,lightweight,and flexibility.In this work,we explored the application of the organic semiconductor Y6-1O single crystal in photodetection devices.Firstly,Y6-1O single crystal material was prepared on a silicon substrate using solution droplet casting method.The optical properties of Y6-1O material were characterized by polarized optical microscopy,fluorescence spectroscopy,etc.,confirming its highly single crystalline performance and emission properties in the near-infrared region.Phototransistors based on Y6-1O materials with different thicknesses were then fabricated and tested.It was found that the devices exhibited good visible to near-infrared photoresponse,with the maximum photoresponse in the near-infrared region at 785 nm.The photocurrent on/off ratio reaches 10^(2),and photoresponsivity reaches 16 mA/W.It was also found that the spectral response of the device could be regulated by gate voltage as well as the material thickness,providing important conditions for optimizing the performance of near-infrared photodetectors.This study not only demonstrates the excellent performance of organic phototransistors based on Y6-1O single crystal material in near-infrared detection but also provides new ideas and directions for the future development of infrared detectors. 展开更多
关键词 near-infrared photodetector organic semiconductor Y6-1O single crystal spectral response
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A Deep Learning-Based Salient Feature-Preserving Algorithm for Mesh Simplification
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作者 Jiming Lan Bo Zeng +2 位作者 Suiqun Li Weihan Zhang Xinyi Shi 《Computers, Materials & Continua》 2025年第5期2865-2888,共24页
The Quadric Error Metrics(QEM)algorithm is a widely used method for mesh simplification;however,it often struggles to preserve high-frequency geometric details,leading to the loss of salient features.To address this l... The Quadric Error Metrics(QEM)algorithm is a widely used method for mesh simplification;however,it often struggles to preserve high-frequency geometric details,leading to the loss of salient features.To address this limitation,we propose the Salient Feature Sampling Points-based QEM(SFSP-QEM)—also referred to as the Deep Learning-Based Salient Feature-Preserving Algorithm for Mesh Simplification—which incorporates a Salient Feature-Preserving Point Sampler(SFSP).This module leverages deep learning techniques to prioritize the preservation of key geometric features during simplification.Experimental results demonstrate that SFSP-QEM significantly outperforms traditional QEM in preserving geometric details.Specifically,for general models from the Stanford 3D Scanning Repository,which represent typical mesh structures used in mesh simplification benchmarks,the Hausdorff distance of simplified models using SFSP-QEM is reduced by an average of 46.58% compared to those simplified using traditional QEM.In customized models such as the Zigong Lantern used in cultural heritage preservation,SFSP-QEM achieves an average reduction of 28.99% in Hausdorff distance.Moreover,the running time of this method is only 6%longer than that of traditional QEM while significantly improving the preservation of geometric details.These results demonstrate that SFSP-QEMis particularly effective for applications requiring high-fidelity simplification while retaining critical features. 展开更多
关键词 Deep learning mesh simplification quadric error metrics(QEM) salient feature preservation point sampling
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Dynamic Characteristic Testing of Wind Turbine Structure Based on Visual Monitoring Data Fusion
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作者 Wenhai Zhao Wanrun Li +2 位作者 Ximei Li Shoutu Li Yongfeng Du 《Structural Durability & Health Monitoring》 2025年第3期593-611,共19页
Addressing the current challenges in transforming pixel displacement into physical displacement in visual monitoring technologies,as well as the inability to achieve precise full-field monitoring,this paper proposes a... Addressing the current challenges in transforming pixel displacement into physical displacement in visual monitoring technologies,as well as the inability to achieve precise full-field monitoring,this paper proposes a method for identifying the structural dynamic characteristics of wind turbines based on visual monitoring data fusion.Firstly,the Lucas-Kanade Tomasi(LKT)optical flow method and a multi-region of interest(ROI)monitoring structure are employed to track pixel displacements,which are subsequently subjected to band pass filtering and resampling operations.Secondly,the actual displacement time history is derived through double integration of the acquired acceleration data and subsequent band pass filtering.The scale factor is obtained by applying the least squares method to compare the visual displacement with the displacement derived from double integration of the acceleration data.Based on this,the multi-point displacement time histories under physical coordinates are obtained using the vision data and the scale factor.Subsequently,when visual monitoring of displacements becomes impossible due to issues such as image blurring or lens occlusion,the structural vibration equation and boundary condition constraints,among other key parameters,are employed to predict the displacements at unknown monitoring points,thereby enabling full-field displacement monitoring and dynamic characteristic testing of the structure.Finally,a small-scale shaking table test was conducted on a simulated wind turbine structure undergoing shutdown to validate the dynamic characteristics of the proposed method through test verification.The research results indicate that the proposed method achieves a time-domain error within the submillimeter range and a frequency-domain accuracy of over 99%,effectively monitoring the full-field structural dynamic characteristics of wind turbines and providing a basis for the condition assessment of wind turbine structures. 展开更多
关键词 Structural health monitoring dynamic characteristics computer vision vibration monitoring data fusion
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Experimental Research Progress and Transformation Strategy Analysis of Dunhuang Medical Prescriptions
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作者 DONG Xiaofei YANG Xiaoyi LI Yingcun 《Chinese Medicine and Culture》 2025年第4期450-466,共17页
Dunhuang medicine is an important part of Dunhuang studies,boasting rich and comprehensive connotations.It records more than 1,000 Dunhuang medical prescriptions,involving internal,external,gynecological,pediatric,Bud... Dunhuang medicine is an important part of Dunhuang studies,boasting rich and comprehensive connotations.It records more than 1,000 Dunhuang medical prescriptions,involving internal,external,gynecological,pediatric,Buddhist,and Daoist medicine,and has demonstrated good clinical effects.However,the mechanism of action of relevant Dunhuang medical prescriptions is still unclear,existing research lacks systematic review and summarization,which has limited their further development.At the same time,the inheritance,innovation,and transformation of Dunhuang medicine are critical issues for the development of Dunhuang medicine,which has important guiding significance for the future development of Dunhuang medicine.Therefore,this study systematically summarizes the experimental research progress of Dunhuang medical prescriptions[except for those contained in Fu Xing Jue Zang Fu Yong Yao Fa Yao(《辅行诀脏腑用药法要》The Guideline to Use Medicines for Zang-fu)],and seven such prescriptions were selected based on three criteria:well-preserved texts,no prior transmission to the outside world,and having extensive research and clinical application over the past decade.The findings indicate that this type of prescription is applicable to a broad spectrum of diseases and has a promising application prospect in health preservation and disease prevention,as it exerts therapeutic effects through multiple targets and pathways.Based on this,specific strategies for the transformation of Dunhuang characteristic prescriptions were proposed from three aspects:inheritance,innovative development,and transformation strategies,aiming to provide insights for the future development of Dunhuang medical prescriptions. 展开更多
关键词 Dunhuang medicine Dunhuang medical prescriptions Development and transformation of Dunhuang medicine Traditional Chinese medicine
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Development of an efficient and expedited cotyledon protoplast-based transient transformation system in Gossypium hirsutum L.
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作者 WANG Zhicheng CAO Shuaiting +6 位作者 CAI Qiuyan GUAN Zhenhui CHENG Hailiang PENG Fanjia LI Yujun ZUO Dongyun SONG Guoli 《Journal of Cotton Research》 2025年第3期352-364,共13页
Background Cotton is an important crop providing the most natural fibers all over the world. The cotton genomics community has utilized whole genome sequencing data to construct an elite gene pool in which functional ... Background Cotton is an important crop providing the most natural fibers all over the world. The cotton genomics community has utilized whole genome sequencing data to construct an elite gene pool in which functional genes are related to agronomic traits. However, the functional validation of these genes is hindered by time-consuming and inefficient genetic transformation methods. Thus, establishing a transient transformation system of high efficiency is necessary for cotton genomics.Results To improve the efficiency of transient transformation, we used the protoplasts isolated from the etiolated cotyledon as recipient. The enzymatic digestion buffer comprised 1.5%(w/v) cellulase, 0.75%(w/v) macerozyme, and 1% hemicellulase, osmotically buffered with 0.4 mol·L^(-1) mannitol. After 5 h of dark incubation at 25℃, uniform cotton protoplasts were successfully isolated with a yield of 4.6 × 10^(6) protoplasts per gram(fresh weight) and 95% viability. We incubated 100 μL protoplasts(2.5 × 10^(5)·m L^(-1)) with 15 μg plasmid in the solution of 0.4 mol·L^(-1) mannitol and 40% PEG 4000 for 15 min, ultimately achieving an optimal transient transfection efficiency of 71.47%.Conclusions This transient system demonstrated effective utility in cellular biology research through successful applications in subcellular localization analyses, bimolecular fluorescence complementation(Bi FC) verification, and prime editing vector validation. Through systematic optimization, we established an efficient and expedited protoplast-based transient transformation system and successfully applied this platform to cotton functional genomics studies. 展开更多
关键词 Cotton Cotyledon protoplast-based transient transformation Prime editing Protoplast isolation Transient expression
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Nonlinear rheological behavior of asphalt based on large amplitude oscillation shear test under different loading,aging,and modification conditions
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作者 Jiaqiu Xu Zijia Wang +3 位作者 Zepeng Fan Junfu Liu Guoyang Lu Dawei Wang 《Journal of Road Engineering》 2025年第1期48-64,共17页
To reveal the effects of environmental and loading conditions, as well as asphalt properties on the nonlinear rheological behavior of asphalt, the large amplitude oscillation shear(LAOS) test was introduced, and the F... To reveal the effects of environmental and loading conditions, as well as asphalt properties on the nonlinear rheological behavior of asphalt, the large amplitude oscillation shear(LAOS) test was introduced, and the Fourier transform rheology, Lissajous curve method, and the LAOS fatigue test have been applied to investigate the nonlinear rheological behavior of asphalt binders. The research results indicate that a decrease in temperature, an increase in shear frequency and strain level, the introduction of polymer modifiers, and the aging effect of asphalt can significantly increase the nonlinearity of asphalt, manifested by the higher relative magnitude of the third harmonic and zero-strain nonlinear coefficient. For the two polymer modifiers selected in this study, the 4%polyurethane modifier exhibits a higher nonlinear lifting effect than the 4% styrene-butadiene-styrene(SBS). The impact of long-term aging on nonlinear viscoelasticity is observably greater than that of short-term aging. The zero-strain nonlinear coefficient estimated based on the average value method can accurately characterize the nonlinear viscoelasticity of asphalt, which can serve as an effective supplement to the relative magnitude of the third harmonic. All asphalts exhibit shear thinning behavior under the test temperature of 24℃, and the decrease in test temperature, the increase in shear rate and strain level, the introduction of modifiers, and the aging effect of asphalt all exacerbate the shear thinning behavior of asphalt. In addition, the fatigue failure process of asphalt materials is accompanied by an increasing degree of nonlinearity. 展开更多
关键词 Nonlinear viscoelasticity Polymer modified asphalt Large amplitude shear oscillation Rheological behavior Shear thinning
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Stock return forecasting based on the proxy variables of category factors
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作者 Yuan Zhao Xue Gong +1 位作者 Weiguo Zhang Weijun Xu 《Financial Innovation》 2025年第1期3181-3228,共48页
Stock return prediction has been in the spotlight because it involves numerous factors.Improving the accuracy of stock return prediction and quantifying the impact of individual factors on forecasting remain challengi... Stock return prediction has been in the spotlight because it involves numerous factors.Improving the accuracy of stock return prediction and quantifying the impact of individual factors on forecasting remain challenging tasks.Motivated by these challenges,we propose a novel forecasting method that entails proxy variables of category factors and the random forest technique.This new method aims to quantify the information and importance of category factors,thereby enhancing the predictability of stock returns.Specifically,we categorize a large set of return predictors into several category factors.We then utilize the importance of the original variables to construct proxy variables for these category factors.Subsequently,we use the proxy variables to build a random forest model for predicting stock returns.Our empirical analysis results demonstrate that the proposed method effectively quantifies the importance of both the original factors and category factors.Furthermore,we find that the fundamental information factor consistently ranks as the most crucial category factor for stock return forecasting.Additionally,the proposed method exhibits a more robust and prominent prediction performance than competing models such as single-category-factor-based random forest models,dimension-reduction,and forecast-combination methods.Most importantly,the proposed method produces forecast results that can assist investors with understanding stock market dynamics and facilitate higher investment returns. 展开更多
关键词 Return prediction Category factors Dimension reduction Random forest
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Lightweight Human Pose Estimation Based on Multi-Attention Mechanism
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作者 LIN Xiao LU Meichen +1 位作者 GAO Mufeng LI Yan 《Journal of Shanghai Jiaotong university(Science)》 2025年第5期899-910,共12页
Human pose estimation has received much attention from the research community because of its wide range of applications.However,current research for pose estimation is usually complex and computationally intensive,esp... Human pose estimation has received much attention from the research community because of its wide range of applications.However,current research for pose estimation is usually complex and computationally intensive,especially the feature loss problems in the feature fusion process.To address the above problems,we propose a lightweight human pose estimation network based on multi-attention mechanism(LMANet).In our method,network parameters can be significantly reduced by lightweighting the bottleneck blocks with depth-wise separable convolution on the high-resolution networks.After that,we also introduce a multi-attention mechanism to improve the model prediction accuracy,and the channel attention module is added in the initial stage of the network to enhance the local cross-channel information interaction.More importantly,we inject spatial crossawareness module in the multi-scale feature fusion stage to reduce the spatial information loss during feature extraction.Extensive experiments on COCO2017 dataset and MPII dataset show that LMANet can guarantee a higher prediction accuracy with fewer network parameters and computational effort.Compared with the highresolution network HRNet,the number of parameters and the computational complexity of the network are reduced by 67%and 73%,respectively. 展开更多
关键词 human pose estimation attention mechanisms multi-scale feature fusion high-resolution networks
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Cross‑sectional anomalies and conditional asset pricing models based on investor sentiment: evidence from the Chinese stock market
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作者 Zhong‑Qiang Zhou Jiajia Wu +1 位作者 Ping Huang Xiong Xiong 《Financial Innovation》 2025年第1期2984-3007,共24页
This study examines a comprehensive set of 30 cross-sectional anomalies in the Chinese A-share market to investigate whether incorporating investor sentiment as conditioning information enhances the explanatory power ... This study examines a comprehensive set of 30 cross-sectional anomalies in the Chinese A-share market to investigate whether incorporating investor sentiment as conditioning information enhances the explanatory power of asset pricing models.Utilizing a long–short portfolio strategy and Fama–MacBeth cross-sectional regression,we find that trading-based anomalies outnumber accounting-based anomalies in the Chinese market.Our results demonstrate that conditional models significantly outperform their unconditional counterparts.Notably,investor sentiment is crucial for capturing the size anomaly when excluding observations from the COVID-19 pandemic period.Additionally,it substantially improves the ability of conditional Fama–French three-factor models to capture individual anomalies and enhances the return–prediction accuracy of conditional CAPMs.We suggest further investigating high-frequency investor sentiment-based conditional models to anticipate stock price fluctuations during extraordinary public health events. 展开更多
关键词 Cross-sectional anomalies Conditional asset pricing Investor sentiment
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Recent applications of EEG-based brain-computer-interface in the medical field 被引量:8
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作者 Xiu-Yun Liu Wen-Long Wang +39 位作者 Miao Liu Ming-Yi Chen Tânia Pereira Desta Yakob Doda Yu-Feng Ke Shou-Yan Wang Dong Wen Xiao-Guang Tong Wei-Guang Li Yi Yang Xiao-Di Han Yu-Lin Sun Xin Song Cong-Ying Hao Zi-Hua Zhang Xin-Yang Liu Chun-Yang Li Rui Peng Xiao-Xin Song Abi Yasi Mei-Jun Pang Kuo Zhang Run-Nan He Le Wu Shu-Geng Chen Wen-Jin Chen Yan-Gong Chao Cheng-Gong Hu Heng Zhang Min Zhou Kun Wang Peng-Fei Liu Chen Chen Xin-Yi Geng Yun Qin Dong-Rui Gao En-Ming Song Long-Long Cheng Xun Chen Dong Ming 《Military Medical Research》 2025年第8期1283-1322,共40页
Brain-computer interfaces(BCIs)represent an emerging technology that facilitates direct communication between the brain and external devices.In recent years,numerous review articles have explored various aspects of BC... Brain-computer interfaces(BCIs)represent an emerging technology that facilitates direct communication between the brain and external devices.In recent years,numerous review articles have explored various aspects of BCIs,including their fundamental principles,technical advancements,and applications in specific domains.However,these reviews often focus on signal processing,hardware development,or limited applications such as motor rehabilitation or communication.This paper aims to offer a comprehensive review of recent electroencephalogram(EEG)-based BCI applications in the medical field across 8 critical areas,encompassing rehabilitation,daily communication,epilepsy,cerebral resuscitation,sleep,neurodegenerative diseases,anesthesiology,and emotion recognition.Moreover,the current challenges and future trends of BCIs were also discussed,including personal privacy and ethical concerns,network security vulnerabilities,safety issues,and biocompatibility. 展开更多
关键词 Brain-computer interfaces(BCIs) Medical applications REHABILITATION COMMUNICATION Brain monitoring DIAGNOSIS
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基于区块链的粮食供需匹配机制构建研究
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作者 王琳 刘伊 《中国农机化学报》 北大核心 2026年第2期168-176,共9页
创新粮食供需匹配机制,是缓解现阶段我国粮食供需紧平衡、降低局部区域粮食供应风险和隐患的现实需求,更是畅通粮食国内大循环、提升粮食产业链供应链韧性的必要举措。基于粮食供需交易实践和区块链技术优势,构建基于区块链的粮食供需... 创新粮食供需匹配机制,是缓解现阶段我国粮食供需紧平衡、降低局部区域粮食供应风险和隐患的现实需求,更是畅通粮食国内大循环、提升粮食产业链供应链韧性的必要举措。基于粮食供需交易实践和区块链技术优势,构建基于区块链的粮食供需匹配机制,重点针对多源异构粮食供需数据构建规范化要素表达方式、设计基于要素相似度的粮食供需匹配算法并给出该算法智能合约实现的关键步骤,最后通过算例验证该匹配机制的科学性与有效性。该匹配机制不仅提供粮食供需数据规范化的语义和结构表达方式,而且能有效解决由时间、地域和信息不对称等因素造成的粮食供需匹配难题,同时通过智能合约的自动执行和动态调节可在无第三方参与的情况下达到可信状态,实现粮食供需交易的高效对接。模拟测试表明,基于区块链的粮食供需匹配机制能显著提高匹配效率,每笔订单平均匹配时间为1.2 s,可同时处理约2250条供需信息单,减少匹配决策的时间成本。 展开更多
关键词 供需匹配 粮食供应链 区块链 智能合约 数据治理
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经济政策不确定性驱动新质生产力:企业韧性与数字化转型的双向赋能
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作者 张江朋 杨斯浩 +1 位作者 付子薇 杨臣 《当代经济》 2026年第2期85-95,共11页
当前全球经济格局深刻变革的背景下,经济政策不确定性显著增强,已成为影响企业发展的重要因素之一。基于中国2014—2023年4952家A股上市公司的面板数据,构建双向固定效应模型分析经济政策不确定性对新质生产力的影响。基于经济政策不确... 当前全球经济格局深刻变革的背景下,经济政策不确定性显著增强,已成为影响企业发展的重要因素之一。基于中国2014—2023年4952家A股上市公司的面板数据,构建双向固定效应模型分析经济政策不确定性对新质生产力的影响。基于经济政策不确定性指数、企业韧性指标及数字化转型程度等变量,验证企业韧性和数字化转型的中介与调节的赋能机制。研究发现,经济政策不确定性与企业新质生产力显著正相关,即较高的不确定性促进新质生产力增长,企业韧性在这一关系中发挥部分中介作用,显示韧性较强的企业在面对不确定性时,通过持续创新更有效地提升了新质生产力;数字化转型对两者关系具有正向调节效应,企业数字化水平的提高可以使经济政策不确定性对新质生产力的正面影响更加显著。进一步分析显示,经济政策不确定性对国有企业和大型企业的新质生产力推动作用更为显著,这可能与此类企业更加完善的治理机制和更强的创新动力有关。该研究为政策不确定何以驱动新质生产力提供了洞察,以期为政府及企业战略规划提供参考。 展开更多
关键词 新质生产力 经济政策不确定性 韧性 数字化转型
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教育数字化转型中师生主体性危机的生成逻辑与化解路径
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作者 白晓丽 姜永志 《继续教育研究》 2026年第1期102-107,共6页
在教育强国建设与教育数字化转型的时代浪潮下,探究教育数字化转型中师生主体性危机,不仅关乎教育质量提升与师生全面发展,还对推动教育数字化转型健康发展、实现教育强国目标有重要价值。深入剖析教育数字化转型中师生主体性危机,认为... 在教育强国建设与教育数字化转型的时代浪潮下,探究教育数字化转型中师生主体性危机,不仅关乎教育质量提升与师生全面发展,还对推动教育数字化转型健康发展、实现教育强国目标有重要价值。深入剖析教育数字化转型中师生主体性危机,认为技术异化使师生关系工具化、价值异化消解教育主体性、主体异化造成教育交往情感疏离。基于此,从师生主体性重建、技术反思深化、教育生态优化三个方面提出教育数字化转型中师生主体性危机的化解路径。 展开更多
关键词 教育数字化 师生主体性危机 生成逻辑
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空间智能的多重演变及其社会重构效应
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作者 文军 吴志鹏 《热带地理》 北大核心 2026年第1期46-54,共9页
空间是地理学的核心概念。在人工智能快速发展的背景下,空间智能展现出前所未有的发展潜力。总体而言,空间智能是空间感知、空间推理与空间行动的有机整体。当前,空间智能领域发生了多重演变,集中体现在:空间感知从一维静态迈向三维动态... 空间是地理学的核心概念。在人工智能快速发展的背景下,空间智能展现出前所未有的发展潜力。总体而言,空间智能是空间感知、空间推理与空间行动的有机整体。当前,空间智能领域发生了多重演变,集中体现在:空间感知从一维静态迈向三维动态,空间推理从既定规则迈向灵活预测,空间行动从情境适配迈向空间共创。但与此同时,空间智能在演变过程中也引发了一系列的社会重构效应,包括数字鸿沟的加剧、隐私泄露的频发、法律标准的滞后等问题。未来,在推动空间智能技术跨学科融合、打造新型智能架构体系的同时,需进一步加强技术的公平性、安全性和规范性建设,充分释放空间智能的普惠效应,构建智能社会新形态。 展开更多
关键词 空间智能 空间感知 空间推理 空间行动 社会重构
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数字技术赋能乡村文化旅游高质量发展的理论逻辑、现实困境与优化路径
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作者 赵晨曦 曾灿 《地理科学》 北大核心 2026年第2期402-411,共10页
从“生产-流通-消费”3个视角出发探究数字技术赋能乡村地区文化旅游高质量发展的理论逻辑,认为数字技术对乡村文化旅游高质量发展具有积极驱动作用,尤其在文化旅游资源配置重组、文化旅游产品创新、流通体系升级、消费服务能力提升等... 从“生产-流通-消费”3个视角出发探究数字技术赋能乡村地区文化旅游高质量发展的理论逻辑,认为数字技术对乡村文化旅游高质量发展具有积极驱动作用,尤其在文化旅游资源配置重组、文化旅游产品创新、流通体系升级、消费服务能力提升等方面具有显著的促进作用。然而目前乡村地区存在数字鸿沟凸显、资源转化动力不足、数字空间治理体系缺失、价值转化内力不足等现实问题,制约数字技术赋能乡村地区数字文化旅游高质量发展。为此应建立规范制度,加强对新型生产组织系统的监管,完善现代流通体系,优化数字语境下的消费“三新”关系。以此促进数字技术赋能乡村文旅高质量发展。 展开更多
关键词 数字赋能 乡村文化旅游高质量发展 现实困境 优化路径
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超声辅助酶解法制备羊骨二肽基肽酶-Ⅳ抑制活性产物的工艺优化及结构特性
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作者 钱敏 夏玲燕 +2 位作者 徐晔 田建军 靳烨 《肉类研究》 北大核心 2026年第1期37-47,共11页
为提升羊骨副产物的资源化利用率,实现其高值化开发,采用超声辅助酶解法制备羊骨中二肽基肽酶-IV(dipeptidyl peptidase-Ⅳ,DPP-Ⅳ)抑制活性产物,以DPP-Ⅳ抑制率为响应值,利用响应面法优化工艺条件,并通过结构表征探究超声辅助酶解对其... 为提升羊骨副产物的资源化利用率,实现其高值化开发,采用超声辅助酶解法制备羊骨中二肽基肽酶-IV(dipeptidyl peptidase-Ⅳ,DPP-Ⅳ)抑制活性产物,以DPP-Ⅳ抑制率为响应值,利用响应面法优化工艺条件,并通过结构表征探究超声辅助酶解对其结构和微观形态的影响。结果显示,羊骨中蛋白质含量较高,脯氨酸和丙氨酸含量丰富,是制备DPP-Ⅳ抑制活性产物的优良原料。木瓜蛋白酶为制备DPP-Ⅳ抑制活性产物的最佳蛋白酶,超声预处理可使酶解产物的DPP-Ⅳ抑制率由(54.70±0.42)%显著提升至(60.61±0.78)%(P<0.05)。通过响应面法优化确定的最佳工艺条件为:超声功率410 W、超声时间30 min、酶解温度54℃、酶解pH 5.8、酶解时间4 h,在此条件下的DPP-Ⅳ抑制率为(61.52±0.37)%。结构表征结果表明,超声预处理可以使酶解产物的二级结构从更规整的α-螺旋转变为无规卷曲或β-折叠,暴露更多疏水基团;微观结构观察结果表明,超声辅助酶解产物颗粒变小,表面出现更细小、致密、均匀的孔洞,有利于酶解反应的进行。 展开更多
关键词 羊骨 二肽基肽酶-Ⅳ 超声辅助酶解 响应面优化 傅里叶变换红外光谱 荧光光谱
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戚继光武学思想的生成逻辑、核心要义及时代价值
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作者 彭国强 杨建营 +1 位作者 翟丰 季浏 《体育学刊》 北大核心 2026年第1期56-63,共8页
运用历史学与体育学交叉研究方法,探讨戚继光武学思想的生成逻辑、核心要义及时代价值。研究认为:抗倭御虏战争催生的军事革新需求构成历史动因、军旅实践与传统武术的批判性吸收形成经验基础、兵学理论与宋明理学的深度融合确立哲学根... 运用历史学与体育学交叉研究方法,探讨戚继光武学思想的生成逻辑、核心要义及时代价值。研究认为:抗倭御虏战争催生的军事革新需求构成历史动因、军旅实践与传统武术的批判性吸收形成经验基础、兵学理论与宋明理学的深度融合确立哲学根基是戚继光武学思想的生成逻辑。核心要义体现为4大维度:构建“分层施训与科学组训”的体系化训练模式;确立“去伪存真与以战验招”的实战化技术标准;创建“长短相依与器为人用”的协同化器械理念;形成“由术至心与以德御武”的身心并铸范式。具体到当下,其体系分层思想可破解武术传承断裂困境;客观求真原则可调和“花法”与“技击”的功能定位;协同发展观能突破拳械分习壁垒;体用兼备理念可为现代武德建设提供历史参照。希冀通过戚继光武学思想的历史分析与现实观照双重视角,为传统武学思想的创造性转化提供理论依据与实践路径。 展开更多
关键词 武学思想 训练体系 武术传承 武术价值 戚继光
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义务教育信息科技课程标准实施的现状、问题与建议——基于全国性大规模调查
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作者 李正福 林晓凡 +5 位作者 冯倩 李素琛 罗舒澄 李锋 魏雄鹰 熊璋 《华东师范大学学报(教育科学版)》 北大核心 2026年第1期80-93,共14页
课程标准的实施是育人蓝图转变为现实的过程,其实施质量在很大程度上决定了课程育人的效果。当前,关于《义务教育信息科技课程标准(2022年版)》在全国范围实施情况的研究不多,本研究以信息科技教师为对象,采用量表调查方法在全国进行了... 课程标准的实施是育人蓝图转变为现实的过程,其实施质量在很大程度上决定了课程育人的效果。当前,关于《义务教育信息科技课程标准(2022年版)》在全国范围实施情况的研究不多,本研究以信息科技教师为对象,采用量表调查方法在全国进行了广泛调研。调查结果反映:大部分教师对信息科技课程标准的改革持有信心,积极参与课程标准学习、课程资源开发建设和教学方法实践创新等课程教学改革活动,普遍具备信息科技课程教学的基本胜任力;同时,存在教师专业不对口、对课程标准理解不深入、现有课程资源难以支持课程标准高质量落实、教学方法适切性欠佳等问题。结合信息科技课程建设的实际情况,可从优化师资配置、提高教育教学能力、创新教学方式、构建数智化资源供给、加强基础研究等方面系统采取相应措施,整体推进信息科技课程标准高质量实施。 展开更多
关键词 信息科技 课程标准 调查研究 课程建设 对策建议
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贵州省3座不同营养型水库浮游植物群落时空格局及影响因子
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作者 邓恺芊 顾太波 +4 位作者 肖晶 王星 王鹏飞 罗江之 李秋华 《水生态学杂志》 北大核心 2026年第2期117-129,共13页
分析不同营养状态水库浮游植物群落结构特征及与关键环境因子间的相互响应,为水库水环境管理和水资源保护提供科学依据。分别于平水期(2020年10月)、枯水期(2021年4月)和丰水期(2021年8月)对贵州省3座不同营养型水库(海龙水库、花溪水... 分析不同营养状态水库浮游植物群落结构特征及与关键环境因子间的相互响应,为水库水环境管理和水资源保护提供科学依据。分别于平水期(2020年10月)、枯水期(2021年4月)和丰水期(2021年8月)对贵州省3座不同营养型水库(海龙水库、花溪水库和万峰水库)浮游植物群落及相关环境因子进行调查,并分析二者间的相关性。结果表明,3座水库综合营养状态指数排序为海龙水库(50.88)>花溪水库(43.06)>万峰水库(38.87);海龙水库鉴定出浮游植物7门59种,花溪水库鉴定出7门59种,万峰水库鉴定出6门47种,3座水库物种组成均为绿藻-蓝藻-硅藻;海龙水库、花溪水库和万峰水库浮游植物细胞平均丰度分别为29.00×10^(6)、3.45×10^(6)和0.56×10^(6)个/L,Shannon-Wiener多样性指数(H')评价结果与均值分别为α-中污染状态(1.04)、α-中污染状态(1.64)和β-中污染状态(2.12);Pielou均匀度指数(J)评价结果与均值分别为中污染(0.35)、轻污染或无污染(0.58)、轻污染或无污染(0.56);在3座水库中,花溪水库和万峰水库的细胞丰度和叶绿素均低于海龙水库,H'和J却相反。主坐标分析(PCoA)和相似性分析(ANOSIM)结果显示3座水库的浮游植物群落结构存在差异,并具有显著的季节特征;富营养状态的海龙水库,枯水期浮游植物丰度显著高于丰水期(P<0.05),中营养的花溪水库和万峰水库浮游植物丰度枯水期显著低于丰水期(P<0.05)。Spearman相关性分析显示,浮游植物丰度与水体透明度(SD)在富营养的海龙水库中呈负相关,而在中营养的花溪水库和万峰水库中相反。冗余分析(RDA)结果显示,透明度(SD)、水温(WT)、高锰酸盐指数(COD_(Mn))、pH和电导率(EC)是影响3座不同营养型水库浮游植物结构差异性的主要环境因子。 展开更多
关键词 浮游植物 群落结构 生境异质性 营养状态 高原水库
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